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“Microscopic investigation of as built and hot isostatic pressed Hastelloy X processed by Selective Laser Melting”. Pourbabak S, Montero-Sistiaga ML, Schryvers D, Van Humbeeck J, Vanmeensel K, Materials characterization 153, 366 (2019). http://doi.org/10.1016/j.matchar.2019.05.024
Abstract: Microstructural characteristics of Hastelloy X produced by Selective Laser Melting have been investigated by various microscopic techniques in the as built (AB) condition and after hot isostatic pressing (HIP). At sub-grain level the AB material consists of columnar high density dislocation cells while the HIP sample consists of columnar sub-grains with lower dislocation density that originate from the original dislocation cells, contradicting existing models. The sub-grains contain nanoscale precipitates enriched in Al, Ti, Cr and O, located at sub-grain boundaries in the AB condition and within the grains after HIP. At some grain boundaries, micrometer sized chromium carbides are detected after HIP. Micro hardness within the grains was found to decrease after HIP, which was attributed to the decrease in dislocation density due to recovery annealing.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 2.714
Times cited: 2
DOI: 10.1016/j.matchar.2019.05.024
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“Impacts of the Hara biosphere reserve on livelihood and welfare in Persian Gulf”. Pour MD, Motiee N, Barati AA, Taheri F, Azadi H, Gebrehiwot K, Lebailly P, Van Passel S, Witlox F, Ecological Economics 141, 76 (2017). http://doi.org/10.1016/J.ECOLECON.2017.05.023
Abstract: Despite the importance of biosphere reserves in Iran's livelihood and welfare, the economic significance of Hara Biosphere Reserve has never been comprehensively studied. This study examines the current importance of Hara Biosphere Reserve (HBR) in local livelihood and welfare. Using a household survey, data were collected through a questionnaire, key informant interviews and direct observations. Two hundred and forty-four households were randomly selected from 10 villages through proportional sampling. Results showed that non-environmental income was the first driver of the total income, poverty alleviation and narrowing income inequality gap. Park income was the second. The results also showed that excluding park income from total income would significantly increase headcount poverty, widen the poverty gap, and raise the Gini coefficient. Wealthier households had the greatest absolute income from the environment, including forest, fishing and fodder. However, the poorest group had smallest absolute income from these sources. Thus, the study demonstrated that wealthier households are responsible for the overharvesting of environmental resources. Interestingly, the study showed that wealthier households are more dependent on profitable environmental incomes sources while the poorest are more dependent on non-profitable ones. (C) 2017 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Economics; Engineering Management (ENM)
Impact Factor: 2.965
Times cited: 7
DOI: 10.1016/J.ECOLECON.2017.05.023
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“Electronic and chemical properties of nickel oxide thin films and the intrinsic defects compensation mechanism”. Poulain R, Lumbeeck G, Hunka J, Proost J, Savolainen H, Idrissi H, Schryvers D, Gauquelin N, Klein A, ACS applied electronic materials 4, 2718 (2022). http://doi.org/10.1021/ACSAELM.2C00230
Abstract: Although largely studied, contradictory results on nickel oxide (NiO) properties can be found in the literature. We herein propose a comprehensive study that aims at leveling contradictions related to NiO materials with a focus on its conductivity, surface properties, and the intrinsic charge defects compensation mechanism with regards to the conditions preparation. The experiments were performed by in situ photo-electron spectroscopy, electron energy loss spectroscopy, and optical as well as electrical measurements on polycrystalline NiO thin films prepared under various preparation conditions by reactive sputtering. The results show that surface and bulk properties were strongly related to the deposition temperature with in particular the observation of Fermi level pinning, high work function, and unstable oxygen-rich grain boundaries for the thin films produced at room temperature but not at high temperature (>200 degrees C). Finally, this study provides substantial information about surface and bulk NiO properties enabling to unveil the origin of the high electrical conductivity of room temperature NiO thin films and also for supporting a general electronic charge compensation mechanism of intrinsic defects according to the deposition temperature.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
DOI: 10.1021/ACSAELM.2C00230
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“Preliminary evaluation of micro-Raman spectrometry for the characterization of individual aerosol particles”. Potgieter-Vermaak SS, Van Grieken R, Applied spectroscopy 60, 39 (2006). http://doi.org/10.1366/000370206775382848
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1366/000370206775382848
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“Fingerprinting of South African ordinary Portland cements, cement blends and mortars for identification purposes: discrimination with starplots and PCA”. Potgieter-Vermaak SS, Potgieter JH, Worobiec A, Van Grieken R, Marjanovic L, Moeketsi S, Cement and concrete research 37, 834 (2007). http://doi.org/10.1016/J.CEMCONRES.2007.02.013
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.CEMCONRES.2007.02.013
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“The application of Raman spectrometry to investigate and characterize cement: part I: a review”. Potgieter-Vermaak SS, Potgieter JH, Van Grieken R, Cement and concrete research 36, 656 (2006). http://doi.org/10.1016/J.CEMCONRES.2005.09.008
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.CEMCONRES.2005.09.008
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“Comparison of limestone, dolomite and fly ash as pre-treatment agents for acid mine drainage”. Potgieter-Vermaak SS, Potgieter JH, Monama P, Van Grieken R, Minerals engineering 19, 454 (2006). http://doi.org/10.1016/J.MINENG.2005.07.009
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.MINENG.2005.07.009
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“A characterisation of the surface properties of an ultra fine fly ash (UFFA) used in the polymer industry”. Potgieter-Vermaak SS, Potgieter JH, Kruger RA, Spolnik Z, Van Grieken R, Fuel 84, 2295 (2005). http://doi.org/10.1016/J.FUEL.2005.05.013
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.FUEL.2005.05.013
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“The application of Raman spectrometry to the investigation of cement: part 2: a micro-Raman study of OPC, slag and fly ash”. Potgieter-Vermaak SS, Potgieter JH, Belleil M, DeWeerdt F, Van Grieken R, Cement and concrete research 36, 663 (2006). http://doi.org/10.1016/J.CEMCONRES.2005.09.010
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.CEMCONRES.2005.09.010
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“Degradation of galvanised iron roofing material in Tanzania by atmospheric corrosion”. Potgieter-Vermaak SS, Mmari A, Van Grieken R, McCrindle RI, Potgieter JH, Corrosion engineering science and technology 46, 642 (2011). http://doi.org/10.1179/147842210X12695149033972
Abstract: Galvanised iron is popular in many applications, particular as a roofing material. However, just like other materials, especially metallic ones, it is prone to degradation by corrosion. In this particular study, the degradation of galvanised roof sheets was investigated at a coastal, urban and rural site in Tanzania, Africa. Samples were exposed to various outdoor environments over a period of 3 years. In addition, some accelerated laboratory investigations were conducted in different simulated air pollution environments in an artificial corrosion chamber constructed for this purpose to supplement the outdoor exposure tests. It was found that the combination of the tropical climate and increasing air pollution due to industrial development in the capital Dar-es-Salaam resulted in substantial atmospheric corrosion of the roof sheets, which eventually leads to failure and the necessity for replacement. The rural site had the lowest degree of atmospheric corrosion as expected. A combination of different corrosion products was identified as a result of the atmospheric corrosion by Raman and EDX analyses. The information gained from this investigation could be utilised to construct more durable structures requiring less frequent replacement and maintenance in future.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1179/147842210X12695149033972
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“Micro-structural characterization of black crust and laser cleaning of building stones by micro-Raman and SEM techniques”. Potgieter-Vermaak SS, Godoi RHM, Van Grieken R, Potgieter JH, Oujja M, Castillejo M, Spectrochimica acta: part A: molecular and biomolecular spectroscopy 61, 2460 (2005). http://doi.org/10.1016/J.SAA.2004.09.010
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SAA.2004.09.010
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“Integrated analytical techniques for the characterisation of environmental particles”. Potgieter-Vermaak S, Van Grieken R, Potgieter JH, Spectroscopy Europe 22, 12 (2010)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“NO2 verkeersmetingen in Vlaanderen door passieve bemonstering”. Potgieter-Vermaak S, Stranger M, Verlinden L, Roekens E, Van Grieken R, Die Suid-Afrikaanse tydskrif vir natuurwetenskap en tegnologie 27, 266 (2008)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Component-specific toxic concerns of the inhalable fraction of urban road dust”. Potgieter-Vermaak S, Rotondo G, Novacovic V, Rollins S, Van Grieken R, Environmental geochemistry and health 34, 689 (2012). http://doi.org/10.1007/S10653-012-9488-5
Abstract: Continuous global urbanisation causes an ever-growing ecological footprint of pollution. Road dust (RD), one of these pollutants, poses a health concern due to carcinogenic and toxic components potentially present in the micron-sized fractions. The literature reports on the concentrations of trace, toxic metals and metalloids present in RD (Hooker and Nathanail in Chem Geol 226:340-351, 2006), but the literature on its molecular composition is limited. Recent reports on the bioaccessibility of platinum group metals are also reported (Colombo et al. in Chem Geol 226:340-351, 2008). In vitro and animal toxicological studies confirmed that the chemical composition of inhaled particles plays a major role in its toxic, genotoxic and carcinogenic mechanisms, but the component-specific toxic effects are still not understood. Particle-bound airborne transition metals can also lead to the production of reactive oxygen species in lung tissue; a special concern amongst particularly susceptible cohorts (children and elderly). The characterisation of the molecular composition of the fine fraction is evidently of importance for public health. During a pilot study, partially characterised size-fractioned RD samples (Barrett et al. in Eviron Sci Technol 44:2940-2946, 2010) were analysed for their elemental concentration using X-ray fluorescence spectrometry and inductively coupled plasma mass spectrometry. In addition, separately dispersed particles (200 particles per size fraction) were analysed individually by means of computer-controlled electron probe X-ray micro-analysis (CC-EPXMA) and their molecular structure probed by studying elemental associations. These were correlated with micro-Raman spectroscopy (MRS) results. It was found that the fine fraction (< 38 mu m) had the highest Pb (238 ppm) and Cr (171 ppm) concentrations. The CC-EPXMA data showed > 50 % association of Cr-rich particles with Pb, and the MRS data showed that the Cr was mostly present as lead chromate and therefore in the Cr(VI) oxidation state. Concentrations of both Pb and Cr decreased substantially (279 (< 38 mu m)-13 ppm (< 1 mm); 171 (< 38 mu m)-91 ppm (< 1 mm), respectively) in the larger fractions. Apart from rather alarmingly high concentrations of oxidative stressors (Cu, Fe, Mn), the carcinogenic and toxic potential of the inhalable fraction is evident. Preliminary bioaccessibility data indicated that both Cr and Pb are readily mobilised in artificial lysosomal liquid and up to 19 % of Cr and 47 % of Pb were released.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S10653-012-9488-5
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“Raman spectroscopy for the analysis of coal : a review”. Potgieter-Vermaak S, Maledi N, Wagner N, van Heerden JHP, Van Grieken R, Potgieter JH, Journal of Raman spectroscopy 42, 123 (2011). http://doi.org/10.1002/JRS.2636
Abstract: The advances in the characterization of amorphous carbons by Raman spectroscopy over the last four decades are of interest to many industries, especially those involving the combustion, gasification and pyrolysis of coal. Many researchers report on the Raman character of the natural organic matter in carbon-containing compounds, such as coal, and relate the Raman bands to the structural order of the amorphous carbons. The basis of most of these studies evolved around the assignment of the G (graphitic, ∼1580 cm−1) band to crystalline graphite and any other bands, called D bands, (disorder, various from 1100 to 1500 cm−1) to any type of structural disorder in the graphitic structure. Concerning coal analysis, the information gained by Raman investigations has been used to describe char evolution as a function of temperature, the presence of catalysts and different gasification conditions. In addition, researchers looked at maturation, grade, doppleritization and many more aspects of interest. One aspect that has, however, not been addressed by most of the researchers is the natural inorganic matter (NIM) in the carbon-containing compounds. Micro-Raman spectroscopy (MRS) has many advantages over other characterization tools, i.e. in situ analysis, nondestructive, no sample preparation, low detection limit, micrometer-scale characterization, versatility and sensitivity to many amorphous compounds. With the distinct advantages it has over that of other molecular characterization tools, such as powder X-ray diffraction (PXRD), Fourier-transform infrared spectrometry (FT-IR) and scanning electron microscopy with X-ray detection (SEM/EDS), it is surprising that it has not yet been fully exploited up to this point for the characterization of the NIM in coal and other amorphous carbons. This paper reviews the work published on the Raman characterization of the natural organic matter (NOM) of coals and reports on preliminary results of the NIM character of various South African coals, whereby various inorganic compounds and minerals in the coal have been characterized.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/JRS.2636
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“Degradation potential of airborne particulate matter at the Alhambra monument : a Raman spectroscopic and electron probe X-ray microanalysis study”. Potgieter-Vermaak S, Horemans B, Anaf W, Cardell C, Van Grieken R, Journal of Raman spectroscopy 43, 1570 (2012). http://doi.org/10.1002/JRS.4052
Abstract: It is well known that airborne particulate matter (APM) has an impact on our cultural heritage. A limited number of articles have been published on the sequential application of elemental and molecular techniques to estimate the degradation potential of APM in environments of cultural heritage importance, and most of these were concerned with indoor environments. The Alhambra monument (Granada, Spain) represents one of the grandest and finest examples of Islamic art and architecture from the Middle Ages. As part of an air quality investigation, two sets of APM were collected at the Hall of the Ambassadors and characterised to determine its potential degradation profile. These were analysed by means of micro-Raman spectroscopy (MRS) and electron probe microanalysis with X-ray detection (EPXMA). The Raman data indicated the presence of various mixed salts of acidic and/or hygroscopic nature, such as sodium and ammonium nitrates and sulfates, especially in the finer fraction. Automated EPXMA estimated this fraction to be as high as 50%. Apart from the potential chemical attack, the soiling due to carbonaceous matter deposition is a real concern. Soot was identified by MRS and EPXMA in all size fractions, reaching values of up to 55%, and was often intertwined with soluble inorganic salts. Ongoing degradation of the pigments is implicated by the presence of brightly coloured particles. MRS and molar abundance ternary diagrams elicited the chemical structure of individual APM so that the degradation potential could be established.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/JRS.4052
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“A case study of high-temperature corrosion in rotary cement kilns”. Potgieter JH, Godoi RHM, Van Grieken R, Journal of the South African Institute of Mining and Metallurgy 104, 603 (2004)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Inelastic electron holography as a variant of the Feynman thought experiment”. Potapov PL, Verbeeck J, Schattschneider P, Lichte H, van Dyck D, Ultramicroscopy 107, 559 (2007). http://doi.org/10.1016/j.ultramic.2006.11.003
Abstract: Using a combination of electron holography and energy filtering, interference fringes produced after inelastic interaction of electrons with hydrogen molecules are examined. Surprisingly, the coherence of inelastic scattering increases when moving from the surface of a hydrogen-containing bubble to the vacuum. This phenomenon can be understood in terms of the Feynman two-slit thought experiment with a variable ambiguity of the which-way registration. (C) 2006 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.843
Times cited: 13
DOI: 10.1016/j.ultramic.2006.11.003
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“Cross-section transmission electron microscopy characterization of the near-surface structure of medical Nitinol superelastic tubing”. Potapov PL, Tirry W, Schryvers D, Sivel VGM, Wu M-Y, Aslanidis D, Zandbergen H, Journal of materials science: materials in medicine 18, 483 (2007). http://doi.org/10.1007/s10856-007-2008-y
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.325
Times cited: 14
DOI: 10.1007/s10856-007-2008-y
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“Microstructural mechanism of development in photothermographic materials”. Potapov PL, Schryvers D, Strijckers H, van Roost C, The journal of imaging science and technology 47, 115 (2003)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.348
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“Measuring the absolute position of EELS ionisation edges in a TEM”. Potapov PL, Schryvers D, Ultramicroscopy 99, 73 (2004). http://doi.org/10.1016/S0304-3991(03)00185-2
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.843
Times cited: 29
DOI: 10.1016/S0304-3991(03)00185-2
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“Nanoscale inhomogeneities in melt-spun Ni-Al”. Potapov PL, Ochin P, Pons J, Schryvers D, Acta materialia 48, 3833 (2000). http://doi.org/10.1016/S1359-6454(00)00188-9
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
Times cited: 28
DOI: 10.1016/S1359-6454(00)00188-9
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“Structural and chemical effects on EELS L3,2 ionization edges in Ni-based intermetallic compounds”. Potapov PL, Kulkova SE, Schryvers D, Verbeeck J, Physical review : B : condensed matter and materials physics 64, 184110 (2001). http://doi.org/10.1103/PhysRevB.64.184110
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 44
DOI: 10.1103/PhysRevB.64.184110
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“Study of changes in L32 EELS ionisation edges upon formation of Ni-based intermetallic compounds”. Potapov PL, Kulkova SE, Schryvers D, Journal of microscopy 210, 102 (2003). http://doi.org/10.1046/j.1365-2818.2003.01176.x
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.692
Times cited: 11
DOI: 10.1046/j.1365-2818.2003.01176.x
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“Effect of charge transfer on EELS integrated cross sections in Mn and Ti oxides”. Potapov PL, Jorissen K, Schryvers D, Lamoen D, Physical review : B : condensed matter and materials physics 70, 045106 (2004). http://doi.org/10.1103/PhysRevB.70.045106
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 28
DOI: 10.1103/PhysRevB.70.045106
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“On the crystal structure of TiNi-Cu martensite”. Potapov P, Shelyakov A, Schryvers D, Scripta materialia 44, 1 (2001). http://doi.org/10.1016/S1359-6462(00)00555-8
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.747
Times cited: 36
DOI: 10.1016/S1359-6462(00)00555-8
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“Nanoscale inhomogeneities in melt-spun Ni-Al”. Potapov P, Ochin P, Pons J, Schryvers D, Journal de physique: 4 11, 439 (2001). http://doi.org/10.1051/jp4:2001873
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 1
DOI: 10.1051/jp4:2001873
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“Experiments on inelastic electron holography”. Potapov P, Lichte H, Verbeeck J, van Dyck D, Ultramicroscopy 106, 1012 (2006). http://doi.org/10.1016/j.ultramic.2006.05.012
Abstract: Using the combination of an electron biprism and an energy filter, the coherence distribution in an inelastically scattered wave-field is measured. It is found that the degree of coherence decreases rapidly with increasing distance between two superimposed points in the object, and with increasing energy-loss. In a Si sample, coherence of plasmon scattering increases in vacuum with the distance from the edge of the sample. (c) 2006 Published by Elsevier B.V.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.843
Times cited: 28
DOI: 10.1016/j.ultramic.2006.05.012
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“Glycogen-graft-poly(2-alkyl-2-oxazolines) –, the new versatile biopolymer-based thermoresponsive macromolecular toolbox”. Pospisilova A, Filippov SK, Bogomolova A, Turner S, Sedlacek O, Matushkin N, Cernochova Z, Stepanek P, Hruby M, RSC advances 4, 61580 (2014). http://doi.org/10.1039/c4ra10315g
Abstract: This study is focused on thermoresponsive glycogen-graft-poly(2-alkyl-2-oxazolines), a new group of nanostructured hybrid dendrimeric stimuli-responsive polymers connecting the body's own biodegradable polysaccharidic dendrimer glycogen with the widely tuneable thermoresponsive behavior of polypeptide-analogic poly(2-alkyl-2-oxazolines), which are known to be biocompatible. Glycogen-graft-poly(2-alkyl-2-oxazolines) were prepared by a simple one-pot two-step procedure involving cationic ring-opening polymerization of 2-alkyl-2-oxazolines followed by termination of the living cationic ends with sodium glycogenate. As confirmed by light and X-ray scattering, as well as cryo-transmission electron microscopy, the grafted dendrimer structure allows easy adjustment of the cloud point temperature, the concentration dependence and nanostructure of the self-assembled phase separated polymer by crosstalk during graft composition, the graft length and the grafting density, in a very wide range.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.108
Times cited: 15
DOI: 10.1039/c4ra10315g
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“K₅Eu(MoO₄)₄, red phosphor for solid state lighting applications, prepared by different techniques”. Posokhova SMM, Morozov VA, Deyneko DVV, Redkin BSS, Spassky DAA, Nagirnyi V, Belik AAA, Hadermann J, Pavlova ETT, Lazoryak BII, CrystEngComm 25, 835 (2023). http://doi.org/10.1039/D2CE01107G
Abstract: The influence of preparation techniques on the structure and luminescent properties of K5Eu(MoO4)(4) (KEMO) was investigated. KEMO phosphors were synthesized by three different techniques: solid state and sol-gel (sg) methods as well as the Czochralski (CZ) crystal growth technique. Laboratory powder X-ray diffraction (PXRD) studies revealed that all KEMO samples had a structure analogous to that of other high temperature alpha-K5R(MoO4)(4) palmierite-type phases (space group (SG) R3m). Contrary to laboratory PXRD data, electron diffraction revealed that the KEMO crystal grown by the CZ technique had a (3 + 1)D incommensurately modulated structure (super space group (SSG) C2/m(0 beta 0)00) with the modulation vector q = 0.689b*. A detailed analysis of electron diffraction patterns has shown formation of three twin domains rotated along the c axis of the R-subcell at 60 degrees with respect to each other. Synchrotron XRD patterns showed additional ultra-wide reflexes in addition to reflections of the R-subcell of the palmierite. However, the insufficient number of reflections, their low intensity and large width in the synchrotron X-ray diffraction patterns made it impossible to refine the structure as incommensurately modulated C2/m(0 beta 0)00. An average structure was refined in the C2/m space group with random distribution of K1 and Eu1 in [M1A(2)O(8)]-layers of the palmierite-type structure. The dependence of luminescent properties on utilized synthesis techniques was studied. The emission spectra of all samples exhibit intense red emission originating from the D-5(0) -> F-7(2) Eu3+ transition. The integrated intensity of the emission from the Eu3+ 5D0 term was found to be the highest in the crystal grown by the CZ technique. The quantum yield measured for KEMO crystals demonstrates a very high value of 66.5%. This fact confirms that KEMO crystals are exceptionally attractive for applications as a near-UV converting red phosphor for LEDs.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.1
DOI: 10.1039/D2CE01107G
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