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Author  |
Xiao, Y.M.; Xu, W.; Zhang, Y.Y.; Peeters, F.M. |
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Title |
Optoelectronic properties of ABC-stacked trilayer graphene |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
250 |
Issue |
1 |
Pages |
86-94 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We present a theoretical study on the optoelectronic properties of ABC-stacked trilayer graphene (TLG). The optical conductance and light transmittance are evaluated through using the energy-balance equation derived from the Boltzmann equation for an air/graphene/dielectric-wafer system in the presence of linearly polarized radiation field. The results obtained from two band structure models are examined and compared. For short wavelength radiation, the universal optical conductance sigma(0) = 3e(2)/(4h) can be obtained. Importantly, there exists an optical absorption window in the radiation wavelength range 10-200 mu m, which is induced by different transition energies required for inter- and intra-band optical absorption channels. As a result, we find that the position and width of this window depend sensitively on temperature and carrier density of the system, especially the lower frequency edge. There is a small characteristic absorption peak at about 82 mu m where the largest interband transition states exist in the ABC-stacked TLG model, in contrast to the relatively smooth curves in a simplified model. These theoretical results indicate that TLG has some interesting and important physical properties which can be utilized to realize infrared or THz optoelectronic devices. |
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Place of Publication |
Berlin |
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Wos |
000313347500011 |
Publication Date |
2012-08-08 |
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Edition |
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ISSN |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
6 |
Open Access |
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Notes |
; This work was supported by the National Natural Science Foundation of China (grant no. 10974206), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. One of us (F.M.P.) was a Specially Appointed Foreign Professor of the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 1.674; 2013 IF: 1.605 |
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Call Number |
UA @ lucian @ c:irua:110109 |
Serial |
2495 |
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Author |
Xiaoyan, S.; Zhang, Y.-R.; Wang, Y.-N.; He, J.-X. |
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Title |
Fluid simulation of the superimposed dual-frequency source effect in inductively coupled discharges |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Physics Of Plasmas |
Abbreviated Journal |
Phys Plasmas |
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Volume |
28 |
Issue |
11 |
Pages |
113504-113510 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Superimposition of dual frequencies (DFs) is one of the methods used for controlling plasma distribution in an inductively coupled plasma (ICP) source. The effects of a superimposed DF on the argon plasma characteristics have been investigated using a two-dimensional self-consistent fluid model. When both currents are fixed at 6A, the plasma density drops with decrease in one of the source frequencies due to less efficient heating and the plasma uniformity improves significantly. Moreover, for ICP operated with superimposed DFs (i.e., 4.52MHz/13.56MHz and 2.26MHz/13.56MHz), the current source exhibits the same period as the low frequency (LF) component, and the plasma density is higher than that obtained at a single frequency (i.e., 4.52 and 2.26MHz) with the same total current of 12A. However, at superimposed current frequencies of 6.78MHz/13.56MHz, the plasma density is lower than that obtained at a single frequency of 6.78MHz due to the weaker negative azimuthal electric field between two positive maxima during one period of 6.78MHz. When the superimposed DF ICP operates at 2.26 and 13.56MHz, the rapid oscillations of the induced electric field become weaker during one period of 2.26MHz as the current ratio of 2.26MHz/13.56MHz rises from 24A/7 A to 30A/1 A, and the plasma density drops with the current ratio due to weakened electron heating. The uniformity of plasma increases due to sufficient diffusion under the low-density condition. |
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Wos |
000760326100004 |
Publication Date |
2021-11-19 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1070-664x |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.115 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 2.115 |
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Call Number |
UA @ admin @ c:irua:187245 |
Serial |
7974 |
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Author |
Xie, L.; Brault, P.; Coutanceau, C.; Bauchire, J.-M.; Caillard, A.; Baranton, S.; Berndt, J.; Neyts, E.C. |
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Title |
Efficient amorphous platinum catalyst cluster growth on porous carbon : a combined molecular dynamics and experimental study |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
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Volume |
162 |
Issue |
162 |
Pages |
21-26 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Amorphous platinum clusters supported on porous carbon have been envisaged for high-performance fuel cell electrodes. For this application, it is crucial to control the morphology of the Pt layer and the Ptsubstrate interaction to maximize activity and stability. We thus investigate the morphology evolution during Pt cluster growth on a porous carbon substrate employing atomic scale molecular dynamics simulations. The simulations are based on the Pt-C interaction potential using parameters derived from density functional theory and are found to yield a Pt cluster morphology similar to that observed in low loaded fuel cell electrodes prepared by plasma sputtering. Moreover, the simulations show amorphous Pt cluster growth in agreement with X-ray diffraction and transmission electron microscopy experiments on high performance low Pt content (10 μgPt cm−2) loaded fuel cell electrodes and provide a fundamental insight in the cluster growth mechanism. |
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Place of Publication |
Amsterdam |
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Wos |
000343686900003 |
Publication Date |
2014-06-26 |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
0926-3373; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.446; 2015 IF: 7.435 |
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Call Number |
c:irua:117949 |
Serial |
874 |
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Author |
Xie, Y. |
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Title |
Bioreactor strategies for sustainable nitrogen cycling based on mineralization/nitrification, partial nitritation/anammox or sulfur-based denitratation |
Type |
Doctoral thesis |
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Year |
2021 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
iv, 205 p. |
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Keywords |
Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
In the biogeochemical flows on Earth, the reactive nitrogen (Nr) level has three times surpassed the safe boundary. The severe transgression of this boundary goes against sustainable planetary development. The modern food production process excessively relies on synthetic Nr fertilizers from the Haber– Bosch process. However, the massive loss of valuable nitrogen resources (i.e., 78-89%) from agriculture has been causing severe nitrogen cascade. Besides, the domestic wastewater in some local areas is discharged without proper treatment, making it a nonnegligible source of Nr pollution for local water bodies. Anthropogenic activities keep pumping out Nr pollution via point-source and non-point-source (NPS) emissions. Compared to the NPS emissions, point sources give visible and identified waste streams. It is vital to intervene the nitrogen cascade from point sources and facilitate humanity back to the safe Nr boundary. The collected and collectible Nr streams from food production, waste management, and recycling secondary raw materials can be used as waste-based fertilizers for agricultural cultivation. Besides the well-investigated recovery of inorganic Nr, organic Nr accounts for a massive Nr proportion on the Earth. Proper handling and treatment make these useful organic fertilizers for soil-based cultivation. However, these organic Nr fertilizers cannot directly apply to fertigation or hydroponic cultivation systems, and further biological conversion via nitrogen mineralization and nitrification to nitrate is essential. Besides the direct Nr cycling, the indirect Nr cycling ‘over the atmosphere’ should also be considered. In this way, the nitrogen cycle can be completed via converting the waste Nr back to nitrogen gas (i.e., Nr removal) and then synthesizing into Nr again. The municipal wastewater treatment plants receive a vast amount of low-strength Nr wastewater (mainly as ammonium) daily. Compared to the conventional nitrification/denitrification process, partial nitritation/anammox (PN/A) is considered a resource- and cost-effective technology for wastewater with a low COD/N ratio. Moreover, the novel autotrophic denitratation/anammox process could be a good Nr removal process for wastewater containing both ammonium and nitrate. This Ph.D. thesis aimed to develop Nr recovery, conversion, and removal bioreactor strategies for different types of waste streams and biomass. Nr recovery was investigated on high-strength Nr waste streams for fertigation or hydroponic applications in Chapters 2 and 3. On the other hand, Nr removal was studied on the medium- to low-strength Nr waste streams in Chapters 4 and 5. In Chapter 2, a novel mineralization and nitrification system was proposed, producing nutrient solutions from solid organic fertilizers for hydroponic systems. Batch tests showed that aerobic incubation at 35°C could realize the NO₃⁻-N production efficiency above 90% from a novel microbial fertilizer. Subsequently, in the stirred tank bioreactor test, NO₃⁻-N production efficiency stabilized in a range of 44-51% under the influent loading rate of 400 mg TN L⁻¹ d⁻¹ at a 5-day HRT. Using Ca(OH)₂ and Mg(OH)₂ as pH control reagents generated the nutrient solutions with different P, Ca, and Mg nutrient levels. After modeling the nutrient balancing process, the proportion of organic-sourced NO₃⁻-N in the Hoagland nutrient solution (HNS) of Ca(OH)₂ scenario was 92.7%, while only 37.4% in the Mg(OH)₂ scenario. Compared to commercial scenarios, the total costs of the organic-sourced HNS can be cost-competitive for hydroponic cultivation. In Chapter 3, the Nr recovery as nitrate (NO₃⁻-N) from diluted human urine (around 670 mg N L⁻¹) was explored in a trickling filter (TF) for the first time. A novel concept of in-situ integrating the TF system into hydroponic systems was proposed as meaningful progress towards sustainable agriculture. The difference between synthetic and real urine in nitrification efficiency was found to be negligible. The full nitrification of alkalinized real urine was realized in the pH-controlled TF by calcium hydroxide (Ca(OH)₂) at around pH 6. The TF could handle different urine collection batches and maintain relatively stable nitrification performance, with NO₃⁻-N production efficiency and rate of 88±3% and 136±4 mg N L⁻¹ d⁻¹, respectively. The optimal HLR to realize this nitrification performance was 2 m³ m⁻² h⁻¹, with energy consumption of 1.8 kWh electricity kg⁻¹ NO₃⁻-N production. Ca(OH)₂, as a cheap base, its triple advantages on urine alkalinization, full nitrification, and macronutrient supplementation were successfully demonstrated in our proposed concept. In Chapter 4, towards more sustainable wastewater treatment, the feasibility of one-stage partial nitritation/anammox (PN/A) was investigated in three parallel packed-bed trickling filters (TFs), with three types of carrier materials of different specific surface areas. Synthetic wastewater containing 100-250 mg NH₄⁺-N L⁻¹ was tested to mimic medium-strength household waste streams after carbon removal. Interestingly, the cheap carrier based on expanded clay achieved similar rates as commercially used plastic carrier materials. The top passive ventilation combined with an optimum hydraulic loading rate of 1.8 m³ m⁻² h⁻¹ could reach approximately 60% total nitrogen (TN) removal at a rate of 300 mg N L⁻¹ d⁻¹. A relatively low NO₃⁻-N production (13%) via PN/A was achieved in TFs. Most of the TN removal took place in the top compartment, where anammox activity was the highest. Energy consumption estimation (0.78 kWh electricity g⁻¹ N removed) suggested that the proposed process could be a suitable low-cost alternative for nitrogen removal. In Chapter 5, coupling sulfur-driven denitratation (SDN) with anammox was proposed to treat the wastewater containing both NO₃⁻-N and NH₄⁺-N, like the secondary effluents of mainstream PN/A processes. To explore the feasibility of sufficient and stable NO₂⁻-N accumulation via SDN in the long term, the effects of pH setpoints, residual NO₃⁻-N level, and biomass-specific NO₃⁻-N loading rate (BSNLR) were investigated. Alternating the pH setpoints between 7.0 and 8.5 could temporarily stimulate the NO₂⁻-N accumulation. Both the residual NO₃⁻-N and BSNLR showed highly positive correlations with the NO₂⁻-N accumulation efficiency. Under the control of pH 8.5, 1.0±0.8 mg NO₃⁻-N L⁻¹ and 150±42 mg NO₃⁻-N g⁻¹ VSS d⁻¹, SDN could produce 6.4±1.0 mg NO₂⁻-N L⁻¹ in the short term. Thiobacillus members may play a crucial role in managing the NO₂⁻-N accumulation, but the reduction of abundance and possible adaptation significantly impaired the efficacy of control strategies in the long run. Overall, novel technologies have been proposed to sustainably convert Nr in waste streams and biomass. The decision for Nr recovery versus removal and synthesis should be based on specific cases with the best environmental, economic, and human-health sustainability. In the future, the Nr management concepts should be further improved to make the nitrogen cycle more sustainable with higher resource use efficiency and less Nr emissions to the environment. Although the thesis is mainly focused on limited types of Nr waste streams, it pointed out the direction of sustainable Nr management and could facilitate the Nr back to the safe boundary in the long run. |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:182099 |
Serial |
7563 |
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Author |
Xie, Y.; Jia, M.; De Wilde, F.; Daeninck, K.; De Clippeleir, H.; Verstraete, W.; Vlaeminck, S.E. |
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Title |
Feasibility of packed-bed trickling filters for partial nitritation/anammox : effects of carrier material, bottom ventilation openings, hydraulic loading rate and free ammonia |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Bioresource technology |
Abbreviated Journal |
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Volume |
373 |
Issue |
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Pages |
128713-128719 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
This study pioneers the feasibility of cost-effective partial nitritation/anammox (PN/A) in packed-bed trickling filters (TFs). Three parallel TFs tested different carrier materials, the presence or absence of bottom ventilation openings, hydraulic loading rates (HLR, 0.4–2.2 m3 m−2 h−1), and free ammonia (FA) levels on synthetic medium. The inexpensive Argex expanded clay was recommended due to the similar nitrogen removal rates as commercially used plastics. Top-only ventilation at an optimum HLR of 1.8 m3 m−2 h−1 could remove approximately 60% of the total nitrogen load (i.e., 300 mg N L-1 d−1, 30 °C) and achieve relatively low NO3–-N accumulation (13%). Likely FA levels of around 1.3–3.2 mg N L-1 suppressed nitratation. Most of the total nitrogen removal took place in the upper third of the reactor, where anammox activity was highest. Provided further optimizations, the results demonstrated TFs are suitable for low-energy shortcut nitrogen removal. |
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Wos |
000945892500001 |
Publication Date |
2023-02-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0960-8524 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 11.4; 2023 IF: 5.651 |
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Call Number |
UA @ admin @ c:irua:193652 |
Serial |
7306 |
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Author |
Xie, Y.; Spiller, M.; Vlaeminck, S.E. |
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Title |
A bioreactor and nutrient balancing approach for the conversion of solid organic fertilizers to liquid nitrate-rich fertilizers : mineralization and nitrification performance complemented with economic aspects |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
The science of the total environment |
Abbreviated Journal |
Sci Total Environ |
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Volume |
806 |
Issue |
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Pages |
150415 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Due to the high water- and nutrient-use efficiency, hydroponic cultivation is increasingly vital in progressing to environment-friendly food production. To further alleviate the environmental impacts of synthetic fertilizer production, the use of recovered nutrients should be encouraged in horticulture and agriculture at large. Solid organic fertilizers can largely contribute to this, yet their physical and chemical nature impedes application in hydroponics. This study proposes a bioreactor for mineralization and nitrification followed by a supplementation step for limiting macronutrients to produce nitrate-based solutions from solid fertilizers, here based on a novel microbial fertilizer. Batch tests showed that aerobic conversions at 35 °C could realize a nitrate (NO₃−-N) production efficiency above 90% and a maximum rate of 59 mg N L−1 d−1. In the subsequent bioreactor test, nitrate production efficiencies were lower (44–51%), yet rates were higher (175–212 mg N L−1 d−1). Calcium and magnesium hydroxide were compared to control the bioreactor pH at 6.0 ± 0.2, while also providing macronutrients for plant production. A mass balance estimation to mimic the Hoagland nutrient solution showed that 92.7% of the NO₃−-N in the Ca(OH)₂ scenario could be organically sourced, while this was only 37.4% in the Mg(OH)₂ scenario. Besides, carbon dioxide (CO₂) generated in the bioreactor can be used for greenhouse carbon fertilization to save operational expenditure (OPEX). An estimation of the total OPEX showed that the production of a nutrient solution from solid organic fertilizers can be cost competitive compared to using commercially available liquid inorganic fertilizer solutions. |
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Wos |
000707640400021 |
Publication Date |
2021-09-20 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0048-9697 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.8 |
Times cited |
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Open Access |
OpenAccess |
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Approved |
Most recent IF: 9.8 |
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Call Number |
UA @ admin @ c:irua:181787 |
Serial |
7132 |
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Author |
Xie, Y.; Van Tendeloo, M.; Zhu, W.; Peng, L.; Vlaeminck, S.E. |
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Title |
Autotrophic nitrogen polishing of secondary effluents : Alkaline pH and residual nitrate control S0-driven denitratation for downstream anammox treatment |
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A1 Journal article |
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Year |
2023 |
Publication |
Journal of Water Process Engineering |
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Volume |
56 |
Issue |
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Pages |
104402-104409 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Energy-lean nitrogen removal technologies, such as partial nitritation/anammox, often encounter effluent issues due to elevated nitrate and ammonium levels. This study proposed a novel autotrophic polishing strategy coupling sulfur-driven denitratation with anammox. To explore the denitratation potential in obtaining stable and sufficient nitrite accumulation, the effects of pH, residual nitrate level, and biomass-specific nitrate loading rate (BSNLR) were investigated in an S0-packed bed reactor at low hydraulic retention time (i.e., 0.2 h). Implementing pH and residual nitrate control strategies would be easier in practice than BSNLR control to polish secondary effluent. Alkaline pH values could realize successful nitrite accumulation without residual nitrate, and further intensify the accumulation under increased residual nitrate levels. The nitrate level was positively correlated with the nitrite accumulation efficiency. At pH 8.5 and nitrate concentration of 1.0 ± 0.8 mg N L−1, sulfur-driven denitratation could successfully maintain nitrite accumulation of 6.4 ± 1.0 mg NO2−-N L−1, ideally for the downstream anammox in case of residual ammonium levels of around 5 mg N L−1. Since Thiobacillus members play a key role in managing nitrite accumulation, their abundance should be guaranteed in the practical application. |
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Wos |
001103341400001 |
Publication Date |
2023-10-18 |
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ISSN |
2214-7144 |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
7 |
Times cited |
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Open Access |
Not_Open_Access: Available from 18.04.2024 |
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Approved |
Most recent IF: 7; 2023 IF: NA |
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Call Number |
UA @ admin @ c:irua:200036 |
Serial |
8835 |
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Author |
Xing, Y.T.; Micklitz, H.; Rappoport, T.G.; Milošević, M.V.; Solorzano-Naranjo, I.G.; Baggio-Saitovitch, E. |
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Title |
Spontaneous vortex phases in superconductor-ferromagnet Pb-Co nanocomposite films |
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A1 Journal article |
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Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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Volume |
78 |
Issue |
22 |
Pages |
224524,1-224524,5 |
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A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report measurements which indicate the appearance of spontaneous vortices in lead superconducting films with embedded magnetic nanoparticles and a temperature-induced phase transition between different vortex phases. Unlike common vortices in superconductors, the vortex phase appears in the absence of applied magnetic field. The vortices nucleate exclusively due to the stray field of the magnetic nanoparticles, which serve the dual role of providing the internal field and simultaneously acting as pinning centers. Transport measurements reveal dynamical phase transitions that depend on temperature (T) and applied field (H) and support the obtained H-T phase diagram. |
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Place of Publication |
Lancaster, Pa |
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Wos |
000262245200092 |
Publication Date |
2008-12-30 |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
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Call Number |
UA @ lucian @ c:irua:76005 |
Serial |
3109 |
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Author |
Xu, B. |
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Title |
Magnetic, calorimetric and electronic properties of vortex states in (3D) mesoscopic superconductors |
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Doctoral thesis |
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2011 |
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Keywords |
Doctoral thesis; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Antwerpen |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:91833 |
Serial |
1863 |
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| Permanent link to this record |
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| |
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Author |
Xu, B.; Milošević, M.V.; Lin, S.-H.; Peeters, F.M.; Jankó, B. |
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| |
Title |
Formation of multiple-flux-quantum vortices in mesoscopic superconductors from simulations of calorimetric, magnetic, and transport properties |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
|
| |
Volume |
107 |
Issue |
5 |
Pages |
057002,1-057002,4 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Because of strong flux confinement in mesoscopic superconductors, a giant vortex may appear in the ground state of the system in an applied magnetic field. This multiquanta vortex can then split into individual vortices (and vice versa) as a function of, e.g., applied current, magnetic field, or temperature. Here we show that such transitions can be identified by calorimetry, as the formation or splitting of a giant vortex results in a clear jump in measured heat capacity versus external drive. We attribute this phenomenon to an abrupt change in the density of states of the quasiparticle excitations in the vortex core(s), and further link it to a sharp change of the magnetic susceptibility at the transitionproving that the formation of a giant vortex can also be detected by magnetometry. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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| |
Language |
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Wos |
000293333100006 |
Publication Date |
2011-07-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
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| |
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.462 |
Times cited |
26 |
Open Access |
|
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| |
Notes |
; We thank O. Bourgeois, T. Yokoyama, M. Eschrig, and M. Ichioka for discussions. This work was supported by FWO-Vlaanderen, the Belgian Science Policy (IAP), the bilateral project Flanders-USA, NSF NIRT, ECS-0609249, and Institute of Theoretical Sciences, Notre Dame. ; |
Approved |
Most recent IF: 8.462; 2011 IF: 7.370 |
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| |
Call Number |
UA @ lucian @ c:irua:91237 |
Serial |
1263 |
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| Permanent link to this record |
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| |
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Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
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| |
Title |
Calorimetric properties of mesoscopic superconducting disks, rings, and cylinders |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
81 |
Issue |
6 |
Pages |
064501,1-064501,10 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The thermal signatures of superconductivity in mesoscopic disks, rings and cylinders are calculated within the Ginzburg-Landau theory. In an applied perpendicular magnetic field H the heat capacity of mesoscopic samples shows a strong dependence on the realized vortex state; discontinuities are found at the critical field for different vorticities, as well as at the superconducting-to-normal state transition. The same applies to the intermediate state of type-I superconductors. Even the subtle changes in the fluxoid distribution inside the sample leave clear signatures on heat capacity, which is particularly useful for fully three-dimensional samples whose interior is often inaccessible by magnetometry. The heat-capacity jump ΔC(H) at the critical temperature exhibits quasiperiodic modulations as a function of magnetic field. In mesoscopic superconducting rings, these oscillations provide calorimetric verification of the Little-Parks effect. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000274998100091 |
Publication Date |
2010-02-01 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
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| |
Notes |
; We are grateful to O. Bourgeois for useful discussions. This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles (IAP) Program-Belgian State-Belgian Science Policy, ESF-JSPS NES program and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:81766 |
Serial |
271 |
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| Permanent link to this record |
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| |
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Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
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| |
Title |
Magnetic properties of vortex states in spherical superconductors |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
77 |
Issue |
14 |
Pages |
144509,1-9 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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| |
Language |
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Wos |
000255457300077 |
Publication Date |
2008-04-07 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
36 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
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| |
Call Number |
UA @ lucian @ c:irua:68845 |
Serial |
1888 |
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| Permanent link to this record |
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Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
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Title |
Second-order multiple-quanta flux entry into a perforated spherical mesoscopic superconductor |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
82 |
Issue |
21 |
Pages |
214501-214501,7 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Flux entry in type-II superconductors without prominent symmetry is a first-order phase transition, where flux enters conventionally gradual in units of a flux quantum. Here we show that neither is necessarily the case in a mesoscopic superconducting sphere with a perforation. In axially applied magnetic field, vortices initially occupy the hole, and can oppose further flux entry in the sample. As a result, multiple-quanta flux entry is found at significantly higher field, and it can manifest as a second-order transition due to suppressed geometric barrier at the equatorial belt of the sample. At high fields a new state is found, with gradually destroyed condensate from the equator inwards, the exact opposite of surface superconductivity. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000286737800007 |
Publication Date |
2010-12-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
|
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| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1), the Belgian Science Policy (IAP), and the ESF “Nanoscience and Engineering in Superconductivity” program. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:88039 |
Serial |
2957 |
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| Permanent link to this record |
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Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
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Title |
Vortex matter in oblate mesoscopic superconductors with a hole: broken symmetry vortex states and multi-vortex entry |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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| |
Volume |
11 |
Issue |
|
Pages |
013020,1-013020,21 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Using three-dimensional (3D) numerical discretization of the GinzburgLandau (GL) equations, we investigate the superconducting state of a sphere with a piercing hole in the presence of a magnetic field. In the case of samples with central perforation, in axially applied homogeneous magnetic field, we realized unconventional vortex states of broken symmetry due to complex, 3D competing interactions, which depend on the GL parameter ê. For certain sizes of the sample, non-hysteretic multi-vortex entry and exit is predicted with the non-existence of some vorticities as stable states. In a tilted magnetic field, we studied the gradual transformation of 3D flux patterns into 1D vortex chains, where vortices align along the perforation, and the evolvement of the multi-vortex entry as well. We analyze the flux-guiding ability of the hole in a tilted field, which leads to fractional flux response in magnetization M(H) curves. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000262932500003 |
Publication Date |
2009-01-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.786 |
Times cited |
8 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
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| |
Call Number |
UA @ lucian @ c:irua:75986 |
Serial |
3873 |
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| Permanent link to this record |
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Author |
Xu, H.; Li, H.; Gauquelin, N.; Chen, X.; Wu, W.-F.; Zhao, Y.; Si, L.; Tian, D.; Li, L.; Gan, Y.; Qi, S.; Li, M.; Hu, F.; Sun, J.; Jannis, D.; Yu, P.; Chen, G.; Zhong, Z.; Radovic, M.; Verbeeck, J.; Chen, Y.; Shen, B. |
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Title |
Giant tunability of Rashba splitting at cation-exchanged polar oxide interfaces by selective orbital hybridization |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Advanced materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The 2D electron gas (2DEG) at oxide interfaces exhibits extraordinary properties, such as 2D superconductivity and ferromagnetism, coupled to strongly correlated electrons in narrow d-bands. In particular, 2DEGs in KTaO3 (KTO) with 5d t2g orbitals exhibit larger atomic spin-orbit coupling and crystal-facet-dependent superconductivity absent for 3d 2DEGs in SrTiO3 (STO). Herein, by tracing the interfacial chemistry, weak anti-localization magneto-transport behavior, and electronic structures of (001), (110), and (111) KTO 2DEGs, unambiguously cation exchange across KTO interfaces is discovered. Therefore, the origin of the 2DEGs at KTO-based interfaces is dramatically different from the electronic reconstruction observed at STO interfaces. More importantly, as the interface polarization grows with the higher order planes in the KTO case, the Rashba spin splitting becomes maximal for the superconducting (111) interfaces approximately twice that of the (001) interface. The larger Rashba spin splitting couples strongly to the asymmetric chiral texture of the orbital angular moment, and results mainly from the enhanced inter-orbital hopping of the t2g bands and more localized wave functions. This finding has profound implications for the search for topological superconductors, as well as the realization of efficient spin-charge interconversion for low-power spin-orbitronics based on (110) and (111) KTO interfaces. An unambiguous cation exchange is discovered across the interfaces of (001), (110), and (111) KTaO3 2D electron gases fabricated at room temperature. Remarkably, the (111) interfaces with the highest superconducting transition temperature also turn out to show the strongest electron-phonon interaction and the largest Rashba spin splitting. image |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001219658400001 |
Publication Date |
2024-03-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0935-9648 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:206037 |
Serial |
9152 |
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| Permanent link to this record |
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Author |
Xu, P.; Neek-Amal, M.; Barber, S.D.; Schoelz, J.K.; Ackerman, M.L.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M. |
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| |
Title |
Unusual ultra-low-frequency fluctuations in freestanding graphene |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
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| |
Volume |
5 |
Issue |
|
Pages |
3720 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Intrinsic ripples in freestanding graphene have been exceedingly difficult to study. Individual ripple geometry was recently imaged using scanning tunnelling microscopy, but these measurements are limited to static configurations. Thermally-activated flexural phonon modes should generate dynamic changes in curvature. Here we show how to track the vertical movement of a one-square-angstrom region of freestanding graphene using scanning tunnelling microscopy, thereby allowing measurement of the out-of-plane time trajectory and fluctuations over long time periods. We also present a model from elasticity theory to explain the very-low-frequency oscillations. Unexpectedly, we sometimes detect a sudden colossal jump, which we interpret as due to mirror buckling. This innovative technique provides a much needed atomic-scale probe for the time-dependent behaviours of intrinsic ripples. The discovery of this novel progenitor represents a fundamental advance in the use of scanning tunnelling microscopy, which together with the application of a thermal load provides a low-frequency nano-resonator. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000335223200007 |
Publication Date |
2014-04-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2041-1723; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
12.124 |
Times cited |
62 |
Open Access |
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| |
Notes |
; This work was financially supported, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Euro-GRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 12.124; 2014 IF: 11.470 |
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| |
Call Number |
UA @ lucian @ c:irua:117201 |
Serial |
3819 |
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| Permanent link to this record |
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Author |
Xu, Q.; Zandbergen, H.W.; van Dyck, D. |
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Title |
Applying an information transmission approach to extract valence electron information from reconstructed exit waves |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
111 |
Issue |
7 |
Pages |
912-919 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
The knowledge of the valence electron distribution is essential for understanding the properties of materials. However this information is difficult to obtain from HREM images because it is easily obscured by the large scattering contribution of core electrons and by the strong dynamical scattering process. In order to develop a sensitive method to extract the information of valence electrons, we have used an information transmission approach to describe the electron interaction with the object. The scattered electron wave is decomposed in a set of basic functions, which are the eigen functions of the Hamiltonian of the projected electrostatic object potential. Each basic function behaves as a communication channel that transfers the information of the object with its own transmission characteristic. By properly combining the components of the different channels, it is possible to design a scheme to extract the information of valence electron distribution from a series of exit waves. The method is described theoretically and demonstrated by means of computer simulations. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000300461000024 |
Publication Date |
2011-02-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
1 |
Open Access |
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| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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| |
Call Number |
UA @ lucian @ c:irua:93623 |
Serial |
146 |
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| Permanent link to this record |
| |
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| |
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Author |
Xu, Q.; Zandbergen, H.W.; van Dyck, D. |
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Title |
Imaging from atomic structure to electronic structure |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Micron |
Abbreviated Journal |
Micron |
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| |
Volume |
43 |
Issue |
4 |
Pages |
524-531 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
This paper discusses the possibility of retrieving the electron distribution (with highlighted valence electron distribution information) of materials from recorded HREM images. This process can be achieved by solving two inverse problems: reconstruction of the exit wave and reconstruction of the electron distribution from exit waves. The first inverse problem can be solved using a focal series reconstruction method. We show that the second inverse problem can be solved by combining a series of exit waves recorded at different thickness conditions. This process is designed based on an improved understanding of the dynamical scattering process. It also explains the fundamental difficulty of obtaining the valence electron distribution information and the basis of our solution. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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| |
Language |
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Wos |
000301702400005 |
Publication Date |
2011-11-05 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
1.98 |
Times cited |
|
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 1.98; 2012 IF: 1.876 |
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| |
Call Number |
UA @ lucian @ c:irua:93634 |
Serial |
1553 |
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| Permanent link to this record |
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Author |
Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D. |
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Title |
Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
81 |
Issue |
11 |
Pages |
115403,1-115403,10 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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| |
Language |
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Wos |
000276248800116 |
Publication Date |
2010-03-03 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
42 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:82273 |
Serial |
1168 |
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| Permanent link to this record |
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Author |
Xu, T.; Wang, P.; Fang, P.; Kan, Y.; Chen, L.; Vleugels, J.; Van der Biest, O.; van Landuyt, J. |
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| |
Title |
Phase assembly and microstructure of CeO2-doped ZrO2 ceramics prepared by spark plasma sintering |
Type |
A1 Journal article |
| |
Year |
2005 |
Publication |
Journal of the European Ceramic Society |
Abbreviated Journal |
J Eur Ceram Soc |
|
| |
Volume |
25 |
Issue |
15 |
Pages |
3437-3442 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
CeO2-doped ZrO2, (8 mol%) starting powder was sintered by means of spark plasma sintering (SPS) at 1300 degrees C without holding time. The stability of the tetragonal ZrO2 phase in the Ce-ZrO2 ceramic sintered under strongly reducing conditions was investigated. The SPS sample consisted of monoclinic and tetragonal ZrO2 phase, with a volume ratio of two to one, as well as a trace amount of a Zr-Ce-O cubic solid solution phase. In contrast, the same powder sintered by hot-pressing in nitrogen at 1300 and 1500 degrees C for 1h showed no tetragonal ZrO2. Microstructural observation of the SPS ceramic by SEM and TEM revealed grains with and without twins. The reason for the appearance of the tetragonal phase in the SPS sample sintered under strongly reducing conditions is discussed. (c) 2004 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Barking |
Editor |
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Language |
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Wos |
000232172100006 |
Publication Date |
2004-12-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0955-2219; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.411 |
Times cited |
13 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 3.411; 2005 IF: 1.567 |
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| |
Call Number |
UA @ lucian @ c:irua:104065 |
Serial |
2576 |
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| Permanent link to this record |
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| |
|
Author |
Xu, W. |
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| |
Title |
Plasma-catalytic DRM : study of LDH derived catalyst for DRM in a GAP plasma system |
Type |
Doctoral thesis |
| |
Year |
2023 |
Publication |
|
Abbreviated Journal |
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| |
Volume |
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Issue |
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Pages |
350 p. |
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| |
Keywords |
Doctoral thesis; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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| |
Abstract |
Plasma is considered one of the promising technologies to solve greenhouse gas problems, as it can activate CO2 and CH4 at relatively low temperatures. Among the various types of plasmas, the gliding arc plasmatron (GAP) is promising, as it has a high level of non-equilibrium and high electron density. Nevertheless, the conversion of CO2 and CH4 in the GAP reactor is limited. Therefore, combining the GAP reactor with catalysts and making use of the heat produced by the plasma to provide thermal energy to the catalyst, forming a post-plasma catalytic (PPC) system, is hypothesized to improve its performance. Therefore, in this PhD research, we investigate important aspects of the PPC concept towards the use of the heat produced by GAP plasma to heat the plasma bed, without additional energy input. Aiming at this, based on a literature study (chapter 1), Ni-loaded layered double hydroxide (LDH) derived catalyst with good thermal catalytic DRM performance were chosen as the catalyst material. Before applying the LDH as a support material, the rehydration property of calcined LDH in moist and liquid environment was studied as part of chapter 2. The data indicated that after high temperatures calcination (600-900 C), the obtained layered double oxides (LDOs) can rehydrate into LDH, although, the rehydrated LDH were different from the original LDH. In chapter 3, different operating conditions, such as gas flow rate, gas compositions (e.g. CH4/CO2 ratio and nitrogen dilution), and addition of H2O were studied to investigate optimal conditions for PPC DRM, identifying possible differences in temperature profiles and exhaust gas compositions that might influence the catalytic performance. Subsequently, the impact of different PPC configurations, making use of the heat and exhaust gas composition produced by the GAP plasma, is shown in Chapter 4. Experiments studying the impact of adjusting the catalyst bed distance to the post-plasma, the catalyst amount, the influence of external heating (below 250 C) and the addition of H2O are discussed. As only limited improvement in the performance was achieved, a new type of catalyst bed was designed and utilized, as described in chapter 5. This improved configuration can realize better heat and mass transfer by directly connecting to the GAP device. The performance was improved and became comparable to the traditional thermal catalytic DRM results obtained at 800 C, although obtained by a fully electrically driven plasma. |
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Wos |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:201534 |
Serial |
9074 |
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| Permanent link to this record |
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Author |
Xu, W.; Buelens, L.C.; Galvita, V.V.; Bogaerts, A.; Meynen, V. |
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Title |
Improving the performance of gliding arc plasma-catalytic dry reforming via a new post-plasma tubular catalyst bed |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Journal of CO2 Utilization |
Abbreviated Journal |
Journal of CO2 Utilization |
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| |
Volume |
83 |
Issue |
|
Pages |
102820 |
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| |
Keywords |
A1 Journal Article; Dry reforming Gliding arc plasma Plasma catalytic DRM Ni-based mixed oxide Post-plasma catalysis; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; |
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| |
Abstract |
A combination of a gliding arc plasmatron (GAP) reactor and a newly designed tubular catalyst bed (N-bed) was applied to investigate the post-plasma catalytic (PPC) effect for dry reforming of methane (DRM). As comparison, a traditional plasma catalyst bed (T-bed) was also utilized. The post-plasma catalytic effect of a Ni-based mixed oxide (Ni/MO) catalyst with a thermal catalytic performance of 77% CO2 and 86% CH4 conversion at 700 ℃ was studied. Although applying the T-bed had little effect on plasma based CO2 and CH4 conversion, an increase in selectivity to H2 was obtained with a maximum value of 89% at a distance of 2 cm. However, even when only α-Al2O3 packing material was used in the N-bed configuration, compared to the plasma alone and the T-bed, an increase of the CO2 and CH4 conversion from 53% and 53% to 69% and 69% to 83% was achieved. Addition of the Ni/MO catalyst further enhanced the DRM reaction, resulting in conversions of 79% for CO2 and 91% for
CH4. Hence, although no insulation nor external heating was applied to the N-bed post plasma, it provides a slightly better conversion than the thermal catalytic performance with the same catalyst, while being fully electrically driven. In addition, an enhanced CO selectivity to 96% was obtained and the energy cost was reduced from ~ 6 kJ/L (plasma alone) to 4.3 kJ/L. To our knowledge, it is the first time that a post-plasma catalytic system achieves this excellent catalytic performance for DRM without extra external heating or insulation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2024-05-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2212-9820 |
ISBN |
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Additional Links |
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| |
Impact Factor |
7.7 |
Times cited |
|
Open Access |
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| |
Notes |
Wencong Xu, Vladimir V. Galvita, Annemie Bogaerts, and Vera Meynen would like to acknowledge the VLAIO Catalisti Moonshot project D2M and the VLAIO Catalisti transition project CO2PERATE (HBC.2017.0692). Lukas C. Buelens acknowledges financial support from the Fund for Scientific Research Flanders (FWO Flanders) through a postdoctoral fellowship grant 12E5623N. Vladimir V. Galvita also acknowledges a personal grant from the Research Fund of Ghent University (BOF; 01N16319). |
Approved |
Most recent IF: 7.7; 2024 IF: 4.292 |
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| |
Call Number |
PLASMANT @ plasmant @ |
Serial |
9131 |
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| Permanent link to this record |
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Author |
Xu, W.; Dong, H.M.; Li, L.L.; Yao, J.Q.; Vasilopoulos, P.; Peeters, F.M. |
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Title |
Optoelectronic properties of graphene in the presence of optical phonon scattering |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
82 |
Issue |
12 |
Pages |
125304-125304,9 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281516500009 |
Publication Date |
2010-09-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
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Notes |
; This work was supported by the Chinese Academy of Sciences, National Natural Science Foundation of China, and Department of Science and Technology of Yunnan Province. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:84260 |
Serial |
2496 |
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| Permanent link to this record |
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Author |
Xu, W.; Leadley, D.R.; Peeters, F.M.; Devreese, J.T.; Nicholas, R.J.; Harris, J.J.; Foxon, C.T. |
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Title |
Destruction of magnetophonon resonance in high mobility heterojunctions from competition between elastic and inelastic scattering |
Type |
P3 Proceeding |
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Year |
1994 |
Publication |
Proceedings of the International Conference on the Physics of Semiconductors |
Abbreviated Journal |
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Volume |
22 |
Issue |
|
Pages |
839-842 |
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Keywords |
P3 Proceeding; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:9284 |
Serial |
665 |
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| Permanent link to this record |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
Diffusion-to-streaming transition in a two-dimensional electron system in a polar semiconductor |
Type |
A1 Journal article |
| |
Year |
1991 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
43 |
Issue |
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Pages |
14134-14141 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Wos |
A1991FQ97400035 |
Publication Date |
0000-00-00 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121; 0163-1829 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.736 |
Times cited |
24 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:913 |
Serial |
701 |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
Electrophonon resonances in a quasi-two-dimensional electron system |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
48 |
Issue |
3 |
Pages |
1562-1570 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
When the energy difference between two electric subbands in a quasi-two-dimensional electron system equals a LO-phonon energy, resonant scattering will occur. This leads to an enhancement of the scattering rate and, consequently, to a suppression of the conductivity. Changing the energy difference between the electric subbands (e.g., through a gate) leads to a series of electrophonon resonances in the conductivity. A detailed study is made of this effect for different confinement potentials. We found that the scattering processes where the emission of a phonon is involved are very important for the electrophonon resonance and that the size of the effect decreases with increasing temperature. |
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Corporate Author |
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Thesis |
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Place of Publication |
Lancaster, Pa |
Editor |
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Wos |
A1993LP05000024 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.736 |
Times cited |
45 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:5747 |
Serial |
1022 |
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| Permanent link to this record |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
The hot electron distribution of two-dimensional electrons in a polar semiconductor at zero temperature |
Type |
A3 Journal article |
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Year |
1991 |
Publication |
Journal of physics: C: condensed matter |
Abbreviated Journal |
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Volume |
3 |
Issue |
|
Pages |
1783-1791 |
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Keywords |
A3 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
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Address |
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Place of Publication |
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Wos |
A1991FE35700009 |
Publication Date |
0000-00-00 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
1 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:948 |
Serial |
1490 |
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| Permanent link to this record |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
Normal and hot electro-phonon resonance effect in a quasi-two-dimensional semiconductor system |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
5 |
Issue |
15 |
Pages |
2307-2320 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
The electro-phonon resonance effect is a consequence of a resonant interaction between two electric subbands mediated by an optical phonon. It occurs in a quasi-two-dimensional electron system each time the energy difference between two electric subbands equals the energy of a Lo phonon. We study the influence of this effect on the electron mobility by using the momentum balance equation. The temperature and electron density dependences of the resonances are studied in the linear and non-linear response regimes. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
A1993KX70100004 |
Publication Date |
2002-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.346 |
Times cited |
18 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:102984 |
Serial |
2367 |
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| Permanent link to this record |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
Streaming-to-accumulation transition in a 2-dimensional electron-system in a polar semiconductor |
Type |
A1 Journal article |
| |
Year |
1992 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
46 |
Issue |
12 |
Pages |
7571-7580 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
Hot-electron transport is studied for a two-dimensional electron gas coupled to longitudinal-optical phonons in crossed electric and magnetic fields. At low electric and high magnetic fields the electrons are accumulated, while at high electric fields they are in a streaming state. We develop a streaming-to-accumulation transition model and compare the results with that from a Monte Carlo simulation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
A1992JQ37800028 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.736 |
Times cited |
13 |
Open Access |
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Notes |
|
Approved |
PHYSICS, APPLIED 28/145 Q1 # |
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| |
Call Number |
UA @ lucian @ c:irua:103023 |
Serial |
3174 |
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| Permanent link to this record |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
Warm-electron transport in a two-dimensional semiconductor |
Type |
A1 Journal article |
| |
Year |
1992 |
Publication |
Semiconductor science and technology |
Abbreviated Journal |
Semicond Sci Tech |
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Volume |
7 |
Issue |
|
Pages |
1251-1256 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
A1992JT73000006 |
Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0268-1242 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.19 |
Times cited |
3 |
Open Access |
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Notes |
|
Approved |
no |
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| |
Call Number |
UA @ lucian @ c:irua:2915 |
Serial |
3903 |
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| Permanent link to this record |
