NANOlab Center of Excellence literature database -- Query Results

	NANOlab Center of Excellence literature database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	211–240 of 607 records found matching your query (RSS):

Select All Deselect All

<< 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 >>

List View

Citations

Details

	Records
	Author	Huang, W.; Li, Y.; Niklas, K.J.; Gielis, J.; Ding, Y.; Cao, L.; Shi, P.
	Title	A superellipse with deformation and its application in describing the cross-sectional shapes of a square bamboo			Type	A1 Journal article
	Year	2020	Publication	Symmetry-Basel	Abbreviated Journal	Symmetry-Basel
	Volume	12	Issue	12	Pages	2073
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Many cross-sectional shapes of plants have been found to approximate a superellipse rather than an ellipse. Square bamboos, belonging to the genus Chimonobambusa (Poaceae), are a group of plants with round-edged square-like culm cross sections. The initial application of superellipses to model these culm cross sections has focused on Chimonobambusa quadrangularis (Franceschi) Makino. However, there is a need for large scale empirical data to confirm this hypothesis. In this study, approximately 750 cross sections from 30 culms of C. utilis were scanned to obtain cross-sectional boundary coordinates. A superellipse exhibits a centrosymmetry, but in nature the cross sections of culms usually deviate from a standard circle, ellipse, or superellipse because of the influences of the environment and terrain, resulting in different bending and torsion forces during growth. Thus, more natural cross-sectional shapes appear to have the form of a deformed superellipse. The superellipse equation with a deformation parameter (SEDP) was used to fit boundary data. We find that the cross-sectional shapes (including outer and inner rings) of C. utilis can be well described by SEDP. The adjusted root-mean-square error of SEDP is smaller than that of the superellipse equation without a deformation parameter. A major finding is that the cross-sectional shapes can be divided into two types of superellipse curves: hyperellipses and hypoellipses, even for cross sections from the same culm. There are two proportional relationships between ring area and the product of ring length and width for both the outer and inner rings. The proportionality coefficients are significantly different, as a consequence of the two different superellipse types (i.e., hyperellipses and hypoellipses). The difference in the proportionality coefficients between hyperellipses and hypoellipses for outer rings is greater than that for inner rings. This work informs our understanding and quantifying of the longitudinal deformation of plant stems for future studies to assess the influences of the environment on stem development. This work is also informative for understanding the deviation of natural shapes from a strict rotational symmetry.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000602546300001	Publication Date	2020-12-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2073-8994	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.7	Times cited		Open Access
	Notes				Approved	Most recent IF: 2.7; 2020 IF: 1.457
	Call Number	UA @ admin @ c:irua:174472			Serial	8622
Permanent link to this record



	Author	Huang, W.; Su, X.; Ratkowsky, D.A.; Niklas, K.J.; Gielis, J.; Shi, P.
	Title	The scaling relationships of leaf biomass vs. leaf surface area of 12 bamboo species			Type	A1 Journal article
	Year	2019	Publication	Global ecology and conservation	Abbreviated Journal
	Volume	20	Issue		Pages	e00793
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	There is convincing evidence for a scaling relationship between leaf dry weight (DW) and leaf surface area (A) for broad-leaved plants, and most estimates of the scaling exponent of DW vs. A are greater than unity. However, the scaling relationship of leaf fresh weight (FW) vs. A has been largely neglected. In the present study, we examined whether there is a statistically strong scaling relationship between FW and A and compared the goodness of fit to that of DW vs. A. Between 250 and 520 leaves from each of 12 bamboo species within 2 genera (Phyllostachys and Pleioblastus) were investigated. The reduced major axis regression protocols were used to determine scaling relationships. The fit for the linearized scaling relationship of FW vs. A was compared with that of DW vs. A using the coefficient of determination (i.e., r2). A stronger scaling relationship between FW and A than that between DW and A was observed for each of the 12 bamboo species investigated. Among the 12 species examined, five had significantly smaller scaling exponents of FW vs. A compared to those of DW vs. A; only one species had a scaling exponent of FW vs. A greater than that of DW vs. A. No significant difference between the two scaling exponents was observed for the remaining 6 species. Researchers conducting future studies might be well advised to consider the influence of leaf fresh weight when exploring the scaling relationships of foliar biomass allocation patterns.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000498226800095	Publication Date	2019-09-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2351-9894; 2351-9894	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:162954			Serial	8497
Permanent link to this record



	Author	Huyskens, C.
	Title	Fouling in submerged membrane bioreactors			Type	Doctoral thesis
	Year	2012	Publication		Abbreviated Journal
	Volume		Issue		Pages	198 p.
	Keywords	Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	978-90-5728-374-1	Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:99492			Serial	7980
Permanent link to this record



	Author	Huyskens, C.; Brauns, E.; van Hoof, E.; de Wever, H.
	Title	A new method for the evaluation of the reversible and irreversible fouling propensity of MBR mixed liquor			Type	A1 Journal article
	Year	2008	Publication	Journal of membrane science	Abbreviated Journal
	Volume	323	Issue	1	Pages	185-192
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	In this paper, a new fouling measurement method is presented as a pragmatic approach to determine a mixed liquor's fouling propensity. The MBR-VFM (VITO Fouling Measurement) uses a specific measurement protocol consisting of alternating filtration and physical cleaning steps, which enables the calculation of both the reversible and the irreversible fouling resistances. The MBR-VFM principle, set-up and measurement protocol are described as well as the evaluation of the fouling measurement method. Finally, the MBR-VFM was validated by comparing the fouling propensity measured on-line by the MBR-VFM in a lab-scale MBR with the fouling of the MBR membranes themselves. Our experiments indicated that the MBR-VFM can accurately measure fouling and that it can even be detected earlier than can be seen from the on-line filtration data of the lab-scale system itself. Furthermore, the differences measured in reversible and irreversible fouling seemed to be related to the observed impact of physical and chemical cleaning respectively. Therefore, the application of the MBR-VFM as an on-line sensor in an advanced control system, enabling the deployment of the measured fouling data for the control of membrane cleaning, seems feasible and will be tested in the near future.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000258904600023	Publication Date	2008-06-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0376-7388	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:88401			Serial	8303
Permanent link to this record



	Author	Huyskens, C.; Brauns, E.; van Hoof, E.; Diels, L.; de Wever, H.
	Title	Validation of a supervisory control system for energy savings in membrane bioreactors			Type	A1 Journal article
	Year	2011	Publication	Water research	Abbreviated Journal
	Volume	45	Issue	3	Pages	1443-1453
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	The application of fixed operational protocols and settings for membrane bioreactors (MBR) often leads to suboptimal filtration conditions due to the dynamic nature of mixed liquor characteristics. With regard to process optimization and energy savings, the potential benefits of a dynamic control system, enabling to adapt fouling control actions (ACS outputs) in an automated way to the actual mixed liquor fouling propensity, are thus obvious. In this paper, the pilot-scale validation of such an advanced control system (ACS) is elaborated. A specific on-line fouling measurement method, the MBR-VFM (VITO Fouling Measurement), was used for the evaluation of the mixed liquors reversible fouling propensity, which was used as a primary ACS input parameter. A first series of tests with a gradual increase in complexity of the selected input and output parameters indicated the functionality of the ACS and demonstrated a substantial reduction of aeration, however sometimes at the expense of a higher fouling rate. The ACS was further fine-tuned and subsequently tested for a longer period under more dynamic operating conditions. A significant correlation was found between the reversible fouling potential measured by the MBR-VFM and the on-line permeability, indicating that the MBR-VFM is a suitable ACS input. Furthermore, an average 22% reduction in aeration flow to the membranes could be achieved without any obvious negative effect on filtration performance. This indicates that this approach is promising to optimize energy consumption in MBRs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000287054500047	Publication Date	2010-11-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0043-1354; 1879-2448	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:88400			Serial	8728
Permanent link to this record



	Author	Huyskens, C.; De Wever, H.; Fovet, Y.; Wegmann, U.; Diels, L.; Lenaerts, S.
	Title	Screening of novel MBR fouling reducers : benchmarking with known fouling reducers and evaluation of their mechanism of action			Type	A1 Journal article
	Year	2012	Publication	Separation and purification technology	Abbreviated Journal	Sep Purif Technol
	Volume	95	Issue		Pages	49-57
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	A novel fouling characterization method was applied for a first screening of two novel synthetic flocculants developed by BASF (BASF-1 and BASF-2) and benchmarking with six well-known products. Results showed that this MBR-VITO Fouling Measurement (VFM) was able to identify beneficial and adverse effects of different additives on the mixed liquor's reversible and irreversible fouling and, in combination with supporting mixed liquor analyses, allowed to identify the additive's main working mechanism. The first screening tests indicated that BASF-1 and BASF-2 reduced reversible and irreversible fouling to a similar extent as the known synthetic flocculants due to a charge neutralization mechanism, resulting in enhanced flocculation and SMP removal. Further testing at different additive concentrations provided a first indication of the optimal dosage and revealed a considerable risk of overdosing for BASF-2, rendering it less suited for fouling control. In contrast, such adverse effects were not observed for BASF-1. BASF-1 induced similar beneficial effects as the known MPE50 polymer at lower dosage and was therefore considered promising for application in MBRs. (C) 2012 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000307032100008	Publication Date	2012-04-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1383-5866	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.359	Times cited	24	Open Access
	Notes	; The authors would like to thank K. Luyckx, J. Fret, L. Heylen, R. Muyshondt, H. Sterckx, J. Verheyden and J. Vande-Velden for technical assistance and V. Iversen for kindly supplying some of the commercial additives. Celine Huyskens is indebted to the Research Foundation-Flanders (FWO). The European Commission is acknowledged for financial support to Aquafit4use (FP7, Grant 211534). ;			Approved	Most recent IF: 3.359; 2012 IF: 2.894
	Call Number	UA @ admin @ c:irua:101903			Serial	5990
Permanent link to this record



	Author	Huyskens, C.; Lenaerts, S.; Brauns, E.; Diels, L.; de Wever, H.
	Title	Study of (ir)reversible fouling in MBRs under various operating conditions using new on-line fouling sensor			Type	A1 Journal article
	Year	2011	Publication	Separation and purification technology	Abbreviated Journal	Sep Purif Technol
	Volume	81	Issue	2	Pages	208-215
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	In this study, a new fouling sensor was validated under different conditions of hydraulic (HRT) and sludge retention time (SRT). The MBR-VFM (membrane bioreactor-VITO Fouling Measurement) allows the simultaneous determination of the physically reversible and irreversible fouling potential of a mixed liquor during a single crossflow filtration test. In accordance with the on-line filtration behavior, the measured reversible and irreversible fouling propensities differed significantly between MBRs operated at different combinations of HRT-SRT. Moreover, a significant negative correlation was found between the on-line permeability and the reversible and irreversible fouling propensity measured by the MBR-VFM. This corresponded to observations made on membrane recovery after physical or chemical cleaning actions. Higher reversible and irreversible fouling were observed at lower HRT, presumably as a consequence of increased concentrations of foulants present. The effect of SRT was much smaller and restricted to the reversible fouling component. Possible explanations for the increased fouling at prolonged SRT are the higher sludge and colloid concentration and the smaller floc size. It can be concluded that the MBR-VFM is a useful tool to monitor fluctuations in a mixed liquors (ir)reversible fouling potential and can contribute to a deeper understanding of the occurring fouling phenomena.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000296108500012	Publication Date	2011-08-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1383-5866	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.359	Times cited	15	Open Access
	Notes	; ;			Approved	Most recent IF: 3.359; 2011 IF: 2.921
	Call Number	UA @ admin @ c:irua:93410			Serial	5992
Permanent link to this record



	Author	Ilgrande, C.; Christiaens, M.; Clauwaert, P.; Vlaeminck, S.E.; Boon, N.
	Title	Can nitrification bring us to Mars? The role of microbial interactions on nitrogen recovery in Life Support Systems			Type	A2 Journal article
	Year	2016	Publication	Communications in agricultural and applied biological sciences	Abbreviated Journal
	Volume	81	Issue	1	Pages	74-79
	Keywords	A2 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	The development cost-effective life support technologies is a highly relevant topic for space biology. Currently, food and water supply during space flights is currently restricted by technical and economic constraints: daily water consumption of an average crew of 6 members is about 72 L, with an estimated cost of 2,160,000 d-1. To reduce these costs and sustain long term space missions, the European Space Agency designed MELiSSA, an artificial ecosystem based on 5 compartments for the recycling gas, liquid and solid waste (Lasseur et al., 2011). In the CI stage, crew and inedible solid waste is fermented by thermophilic anaerobic bacteria, producing volatile fatty acids (VFAs), CO2 and ammonium (NH4+). In the CII compartment the VFAs are converted into edible biomass, using the photoheterotroph Rodospirillum rubrum. Afterwards, the nitrifying CIII unit converts toxic levels of ammonia/ammonium into nitrate, which enables the effluent to be fed to the photoautotrohopic CIV stage, that provides food and oxygen for the crew (Godia et al., 2002). The highest nitrogen flux in a Life Support System is human urine. As nitrate is the preferred form of nitrogen fertilizer for hydroponic plant cultivation, urine nitrification is an essential process in the MELiSSA loop. The development of the Additional Unit for Water Treatment or Urine NItrification ConsortiUM (UNICUM) requires the selection and characterization of the microorganisms that will be used. The key microorganisms in the biological treatment of urine are heterotrophs, for the hydrolysis of urea into ammonia and carbon dioxide, Ammonia Oxidizing Bacteria (AOB), for the ammonia oxidation into nitrite and Nitrite Oxidizing Bacteria (NOB), for the conversion of nitrite into nitrate. The strains were selected according to predefined safety (non sporogenic and BSL 1) and metabolic (Ks, μmax) criteria. To evaluate functional consortia for space applications, ureolysis, nitritation and nitratation of the selected microorganisms and synthetic communities were elucidated. Additionally, urine is a matrix with a high salt content. Unhydrolised urine's EC ranges from 1.1 to 33.9 mS/cm, the mean value being 21.5 mS/cm (Marickar, 2010), while hydrolysed urine can reach higher levels, up to 75 mS/cm. This conditions could inhibit microbial metabolism, therefore the effect of salinity on urine nitrification was also elucidated.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1379-1176	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:151151			Serial	7573
Permanent link to this record



	Author	Ilgrande, C.; Defoirdt, T.; Vlaeminck, S.E.; Boon, N.; Clauwaert, P.
	Title	Media optimization, strain compatibility, and low-shear modeled microgravity exposure of synthetic microbial communities for urine nitrification in regenerative life-support systems			Type	A1 Journal article
	Year	2019	Publication	Astrobiology	Abbreviated Journal
	Volume	19	Issue	11	Pages	1353-1362
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Urine is a major waste product of human metabolism and contains essential macro- and micronutrients to produce edible microorganisms and crops. Its biological conversion into a stable form can be obtained through urea hydrolysis, subsequent nitrification, and organics removal, to recover a nitrate-enriched stream, free of oxygen demand. In this study, the utilization of a microbial community for urine nitrification was optimized with the focus for space application. To assess the role of selected parameters that can impact ureolysis in urine, the activity of six ureolytic heterotrophs (Acidovorax delafieldii, Comamonas testosteroni, Cupriavidus necator, Delftia acidovorans, Pseudomonas fluorescens, and Vibrio campbellii) was tested at different salinities, urea, and amino acid concentrations. The interaction of the ureolytic heterotrophs with a nitrifying consortium (Nitrosomonas europaea ATCC 19718 and Nitrobacter winogradskyi ATCC 25931) was also tested. Lastly, microgravity was simulated in a clinostat utilizing hardware for in-flight experiments with active microbial cultures. The results indicate salt inhibition of the ureolysis at 30 mS cm(-1), while amino acid nitrogen inhibits ureolysis in a strain-dependent manner. The combination of the nitrifiers with C. necator and V. campbellii resulted in a complete halt of the urea hydrolysis process, while in the case of A. delafieldii incomplete nitrification was observed, and nitrite was not oxidized further to nitrate. Nitrate production was confirmed in all the other communities; however, the other heterotrophic strains most likely induced oxygen competition in the test setup, and nitrite accumulation was observed. Samples exposed to low-shear modeled microgravity through clinorotation behaved similarly to the static controls. Overall, nitrate production from urea was successfully demonstrated with synthetic microbial communities under terrestrial and simulated space gravity conditions, corroborating the application of this process in space.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000492817700004	Publication Date	2019-10-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1557-8070; 1531-1074	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:164663			Serial	8215
Permanent link to this record



	Author	Ilgrande, C.; Leroy, B.; Wattiez, R.; Vlaeminck, S.E.; Boon, N.; Clauwaert, P.
	Title	Metabolic and proteomic responses to salinity in synthetic nitrifying communities of Nitrosomonas spp. and Nitrobacter spp			Type	A1 Journal article
	Year	2018	Publication	Frontiers in microbiology	Abbreviated Journal
	Volume	9	Issue		Pages	2914
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Typically, nitrification is a two-stage microbial process and is key in wastewater treatment and nutrient recovery from waste streams. Changes in salinity represent a major stress factor that can trigger response mechanisms, impacting the activity and the physiology of bacteria. Despite its pivotal biotechnological role, little information is available on the specific response of nitrifying bacteria to varying levels of salinity. In this study, synthetic communities of ammonia-oxidizing bacteria (AOB Nitrosomonas europaea and/or Nitrosomonas ureae) and nitrite-oxidizing bacteria (NOB Nitrobacter winogradskyi and/or Nitrobacter vulgaris) were tested at 5, 10, and 30 mS cm-1 by adding sodium chloride to the mineral medium (0, 40, and 200 mM NaCl, respectively). Ammonia oxidation activity was less affected by salinity than nitrite oxidation. AOB, on their own or in combination with NOB, showed no significant difference in the ammonia oxidation rate among the three conditions. However, N. winogradskyi improved the absolute ammonia oxidation rate of both N. europaea and N. ureae. N. winogradskyis nitrite oxidation rate decreased to 42% residual activity upon exposure to 30 mS cm-1, also showing a similar behavior when tested with Nitrosomonas spp. The nitrite oxidation rate of N. vulgaris, as a single species, was not affected when adding sodium chloride up to 30 mS cm-1, however, its activity was completely inhibited when combined with Nitrosomonas spp. in the presence of ammonium/ammonia. The proteomic analysis of a co-culture of N. europaea and N. winogradskyi revealed the production of osmolytes, regulation of cell permeability and an oxidative stress response in N. europaea and an oxidative stress response in N. winogradskyi, as a result of increasing the salt concentration from 5 to 30 mS cm-1. A specific metabolic response observed in N. europaea suggests the role of carbon metabolism in the production of reducing power, possibly to meet the energy demands of the stress response mechanisms, induced by high salinity. For the first time, metabolic modifications and response mechanisms caused by the exposure to salinity were described, serving as a tool toward controllability and predictability of nitrifying systems exposed to salt fluctuations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000451903700001	Publication Date	2018-11-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1664-302x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:155237			Serial	8217
Permanent link to this record



	Author	Ilgrande, C.; Mastroleo, F.; Christiaens, M.E.R.; Lindeboom, R.E.F.; Prat, D.; Van Hoey, O.; Ambrozova, I.; Coninx, I.; Heylen, W.; Pommerening-Roser, A.; Spieck, E.; Boon, N.; Vlaeminck, S.E.; Leys, N.; Clauwaert, P.
	Title	Reactivation of microbial strains and synthetic communities after a spaceflight to the International Space Station : corroborating the feasibility of essential conversions in the MELiSSA Loop			Type	A1 Journal article
	Year	2019	Publication	Astrobiology	Abbreviated Journal
	Volume	19	Issue	9	Pages	1167-1176
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	To sustain human deep space exploration or extra-terrestrial settlements where no resupply from the Earth or other planets is possible, technologies for in situ food production, water, air, and waste recovery need to be developed. The Micro-Ecological Life Support System Alternative (MELiSSA) is such a Regenerative Life Support System (RLSS) and it builds on several bacterial bioprocesses. However, alterations in gravity, temperature, and radiation associated with the space environment can affect survival and functionality of the microorganisms. In this study, representative strains of different carbon and nitrogen metabolisms with application in the MELiSSA were selected for launch and Low Earth Orbit (LEO) exposure. An edible photoautotrophic strain (Arthrospira sp. PCC 8005), a photoheterotrophic strain (Rhodospirillum rubrum S1H), a ureolytic heterotrophic strain (Cupriavidus pinatubonensis 1245), and combinations of C. pinatubonensis 1245 and autotrophic ammonia and nitrite oxidizing strains (Nitrosomonas europaea ATCC19718, Nitrosomonas ureae Nm10, and Nitrobacter winogradskyi Nb255) were sent to the International Space Station (ISS) for 7 days. There, the samples were exposed to 2.8 mGy, a dose 140 times higher than on the Earth, and a temperature of 22 degrees C +/- 1 degrees C. On return to the Earth, the cultures were reactivated and their growth and activity were compared with terrestrial controls stored under refrigerated (5 degrees C +/- 2 degrees C) or room temperature (22 degrees C +/- 1 degrees C and 21 degrees C +/- 0 degrees C) conditions. Overall, no difference was observed between terrestrial and ISS samples. Most cultures presented lower cell viability after the test, regardless of the type of exposure, indicating a harsher effect of the storage and sample preparation than the spaceflight itself. Postmission analysis revealed the successful survival and proliferation of all cultures except for Arthrospira, which suffered from the premission depressurization test. These observations validate the possibility of launching, storing, and reactivating bacteria with essential functionalities for microbial bioprocesses in RLSS.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000475278300001	Publication Date	2019-06-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1557-8070; 1531-1074	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:161342			Serial	8456
Permanent link to this record



	Author	Jammaer, J.; Aprile, C.; Verbruggen, S.W.; Lenaerts, S.; Pescarmona, P.P.; Martens, J.A.
	Title	A non-aqueous synthesis of TiO₂SiO₂ composites in supercritical CO₂ for the photodegradation of pollutants			Type	A1 Journal article
	Year	2011	Publication	Chemsuschem	Abbreviated Journal	Chemsuschem
	Volume	4	Issue	10	Pages	1457-1463
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Titania/silica composites with different Ti/Si ratios are synthesized via a nonconventional synthesis route. The synthesis involves non-aqueous reaction of metal alkoxides and formic acid at 75 °C in supercritical carbon dioxide. The as-prepared composite materials contain nanometer-sized anatase crystallites and amorphous silica. Large specific surface areas are obtained. The composites are evaluated in the photocatalytic degradation of phenol in aqueous medium, and in the elimination of acetaldehyde from air. The highest photocatalytic activity in both processes is achieved with a composite containing 40 wt % TiO2.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000296497400010	Publication Date	2011-05-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1864-5631	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.226	Times cited	15	Open Access
	Notes	; The authors acknowledge sponsorship from CECAT and Methusalem (long-term financing of the Flemish government). We thank Dr. E. Gobechiya for assistance with XRD measurements and A. Lemaire for assistance with mercury porosimetry measurements. ;			Approved	Most recent IF: 7.226; 2011 IF: 6.827
	Call Number	UA @ admin @ c:irua:93363			Serial	5973
Permanent link to this record



	Author	Jochems, P.
	Title	Process intensification by immobilization of \beta-galactosidase on a mixed matrix membrance : galacto-oligosaccharides production as a case study			Type	Doctoral thesis
	Year	2013	Publication		Abbreviated Journal
	Volume		Issue		Pages	199 p.
	Keywords	Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	978-90-5728-430-4	Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:111811			Serial	8415
Permanent link to this record



	Author	Jochems, P.; Mueller, T.; Satyawali, Y.; Diels, L.; Dejonghe, W.; Hanefeld, U.
	Title	Active site titration of immobilized beta-galactosidase for the determination of active enzymes			Type	A1 Journal article
	Year	2015	Publication	Biochemical engineering journal	Abbreviated Journal
	Volume	93	Issue		Pages	137-141
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	In the present study, an active site titration method is demonstrated, to determine the amount of active enzyme (beta-galactosidase), immobilized on a support. Two types of supports were investigated, viz, amino acrylic resin and a mixed matrix membrane. Furthermore, 2',4'-dinitrophenyl 2-deoxy-2-fluoro-beta-D-galactopyranoside was used as an inhibitor for the active site titration of immobilized beta-galactosidase obtained from Kluyveromyces lactis. Using the active site titration, approximately 8.3 mg of active enzyme was found on 1 g of dried commercially available SPRIN imibond, which is an amino acrylic resin with covalently bound beta-galactosidase obtained from K. lactis. However, this method, in its present form, was not effective on the mixed matrix membranes due to the irreversible partial adsorption of the leaving group (2',4'-dinitrophenolate) by the membrane. This observation implied that it is important to investigate interactions between the support and the used inhibitor and leaving group. (C) 2014 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000347362100018	Publication Date	2014-10-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1369-703x; 1873-295x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:123763			Serial	7417
Permanent link to this record



	Author	Jochems, P.; Satyawali, Y.; Diels, L.; Dejonghe, W.
	Title	Enzyme immobilization on/in polymeric membranes : status, challenges and perspectives in biocatalytic membrane reactors (BMRs)			Type	A1 Journal article
	Year	2011	Publication	Green chemistry : cutting-edge research for a greener sustainable future	Abbreviated Journal
	Volume	13	Issue	7	Pages	1609-1623
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Immobilization of enzymes is beneficial in terms of improving the process economics by enabling enzyme re-use and enhancing overall productivity and robustness. Increasingly, membranes are thought to be good supports for enzyme immobilization. These resulting biocatalytic membranes are integrated in reactors known as biocatalytic membrane reactors (BMRs) which enable the integration of biocatalysis and separation. Often the available commercial membranes require modifications to make them suitable for enzyme immobilization. Different immobilization techniques can be used on such suitable membranes, but no general rules exist for making a choice between them. Despite the advantages of BMR application, there are some issues which need to be addressed in order to achieve up-scaling of such systems. In this review, the different aspects of enzyme immobilization on membranes are discussed to show the complexity of this interdisciplinary technology. In addition, the existing issues which require further investigation are highlighted.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000292450600002	Publication Date	2011-05-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9262; 1463-9270	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:89567			Serial	7930
Permanent link to this record



	Author	Jochems, P.; Satyawali, Y.; van Roy, S.; Doyen, W.; Diels, L.; Dejonghe, W.
	Title	Characterization and optimization of \beta-galactosidase immobilization process on a mixed-matrix membrane			Type	A1 Journal article
	Year	2011	Publication	Enzyme and microbial technology	Abbreviated Journal
	Volume	49	Issue	6/7	Pages	580-588
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	β-Galactosidase is an important enzyme catalyzing not only the hydrolysis of lactose to the monosaccharides glucose and galactose but also the transgalactosylation reaction to produce galacto-oligosaccharides (GOS). In this study, β-galactosidase was immobilized by adsorption on a mixed-matrix membrane containing zirconium dioxide. The maximum β-galactosidase adsorbed on these membranes was 1.6 g/m2, however, maximal activity was achieved at an enzyme concentration of around 0.5 g/m2. The tests conducted to investigate the optimal immobilization parameters suggested that higher immobilization can be achieved under extreme parameters (pH and temperature) but the activity was not retained at such extreme operational parameters. The investigations on immobilized enzymes indicated that no real shift occurred in its optimal temperature after immobilization though the activity in case of immobilized enzyme was better retained at lower temperature (5 °C). A shift of 0.5 unit was observed in optimal pH after immobilization (pH 6.5 to 7). Perhaps the most striking results are the kinetic parameters of the immobilized enzyme; while the Michaelis constant (Km) value increased almost eight times compared to the free enzyme, the maximum enzyme velocity (Vmax) remained almost constant.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000298529600015	Publication Date	2011-06-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0141-0229	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:90060			Serial	7608
Permanent link to this record



	Author	Joris, I.; Bronders, J.; van der Grift, B.; Seuntjens, P.
	Title	Model-based scenario analysis of the impact of remediation measures on metal leaching from soils contaminated by historic smelter emissions			Type	A1 Journal article
	Year	2014	Publication	Journal of environmental quality	Abbreviated Journal
	Volume	43	Issue	3	Pages	859-868
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	A spatially distributed model for leaching of Cd from the unsaturated zone was developed for the Belgian-Dutch transnational Kempen region. The model uses as input land-use maps, atmospheric deposition data, and soil data and is part of a larger regional model that simulates transport of Cd in soil, groundwater, and surface water. A new method for deriving deposition from multiple sites was validated using soil data in different wind directions. Leaching was calculated for the period 1890 to 2010 using a reconstruction of metal loads in the region. The model was able to reproduce spatial patterns of concentrations in soil and groundwater and predicted the concentration in shallow groundwater adequately well for the purpose of evaluating management options. For 42% of the data points, measurements and calculations were within the same concentration class. The model was used for forecasting under a reference scenario, an autonomous development scenario including climate change, and a scenario with implementation of remediation measures. The impact of autonomous development (under the most extreme scenario of climatic change) amounted to an increase of 10% in cumulative Cd flux after 100 yr as compared with the reference scenario. The impact of remediation measures was mainly local and is less pronounced (i.e., only 3% change in cumulative flux at the regional scale). The integrated model served as a tool to assist in developing management strategies and prioritization of remediation of the wide-spread heavy metal contamination in the region.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000336275700009	Publication Date	2014-04-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0047-2425	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:117781			Serial	8260
Permanent link to this record



	Author	Kerckhof, F.-M.; Sakarika, M.; Van Giel, M.; Muys, M.; Vermeir, P.; De Vrieze, J.; Vlaeminck, S.E.; Rabaey, K.; Boon, N.
	Title	From biogas and hydrogen to microbial protein through co-cultivation of methane and hydrogen oxidizing bacteria			Type	A1 Journal article
	Year	2021	Publication	Frontiers in Bioengineering and Biotechnology	Abbreviated Journal
	Volume	9	Issue		Pages	733753
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Increasing efforts are directed towards the development of sustainable alternative protein sources among which microbial protein (MP) is one of the most promising. Especially when waste streams are used as substrates, the case for MP could become environmentally favorable. The risks of using organic waste streams for MP production–the presence of pathogens or toxicants–can be mitigated by their anaerobic digestion and subsequent aerobic assimilation of the (filter-sterilized) biogas. Even though methane and hydrogen oxidizing bacteria (MOB and HOB) have been intensively studied for MP production, the potential benefits of their co-cultivation remain elusive. Here, we isolated a diverse group of novel HOB (that were capable of autotrophic metabolism), and co-cultured them with a defined set of MOB, which could be grown on a mixture of biogas and H2/O2. The combination of MOB and HOB, apart from the CH4 and CO2 contained in biogas, can also enable the valorization of the CO2 that results from the oxidation of methane by the MOB. Different MOB and HOB combinations were grown in serum vials to identify the best-performing ones. We observed synergistic effects on growth for several combinations, and in all combinations a co-culture consisting out of both HOB and MOB could be maintained during five days of cultivation. Relative to the axenic growth, five out of the ten co-cultures exhibited 1.1–3.8 times higher protein concentration and two combinations presented 2.4–6.1 times higher essential amino acid content. The MP produced in this study generally contained lower amounts of the essential amino acids histidine, lysine and threonine, compared to tofu and fishmeal. The most promising combination in terms of protein concentration and essential amino acid profile was Methyloparacoccus murrelli LMG 27482 with Cupriavidus necator LMG 1201. Microbial protein from M. murrelli and C. necator requires 27–67% less quantity than chicken, whole egg and tofu, while it only requires 15% more quantity than the amino acid-dense soybean to cover the needs of an average adult. In conclusion, while limitations still exist, the co-cultivation of MOB and HOB creates an alternative route for MP production leveraging safe and sustainably-produced gaseous substrates.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000697897900001	Publication Date	2021-09-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2296-4185	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:180591			Serial	7985
Permanent link to this record



	Author	Keulemans, M.
	Title	Study of electron transfer processes in plasmonic photocatalysis			Type	Doctoral thesis
	Year	2017	Publication		Abbreviated Journal
	Volume		Issue		Pages	170 p.
	Keywords	Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:147504			Serial	8596
Permanent link to this record



	Author	Keulemans, M.; Verbruggen, S.W.; Hauchecorne, B.; Martens, J.A.; Lenaerts, S.
	Title	Activity versus selectivity in photocatalysis : morphological or electronic properties tipping the scale			Type	A1 Journal article
	Year	2016	Publication	Journal of catalysis	Abbreviated Journal	J Catal
	Volume	344	Issue		Pages	221-228
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	In this paper a structure-activity and structure-selectivity relation is established for three commercial TiO2 sources (P25, P90, and PC500). Morphological and electronic parameters of the photocatalysts are determined using widely applicable and inexpensive characterization procedures. More specifically, the electronic properties are rigorously characterized using an electron titration method yielding quantitative information on the amount of defect sites present in the catalyst. Surface photovoltage measurements on the other hand provide complementary information on the charge carrier recombination process. As model reaction, the degradation of a solid layer of stearic acid is studied using an in situ FTIR reaction cell that enables to investigate the catalyst surface and possible formation of reaction intermediates while the reactions are ongoing. We show that the order of photocatalytic conversion is PC500 > P90 > P25, matching the order of favorable morphological properties. In terms of selectivity to CO2 formation (complete mineralization), however, this trend is reversed: P25 > P90 > PC500, now matching the order of advantageous electronic properties, i.e. low charge carrier recombination and high charge carrier generation. With this we intend to provide new mechanistic insights using a wide variety of physical, (wet) chemical and operando analysis methods that aid the development of performant (self-cleaning) photocatalytic materials.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000390182800022	Publication Date	2016-10-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-9517	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.844	Times cited	10	Open Access
	Notes	; M.K. acknowledges Flemish Agency for Innovation & Entrepreneurship for the doctoral scholarship. S.W.V. acknowledges the Fonds Wetenschappelijk Onderzoek (FWO) for a post-doctoral fellowship. J.A.M. acknowledges the Flemish government for long-term structural funding (Methusalem). ;			Approved	Most recent IF: 6.844
	Call Number	UA @ admin @ c:irua:136339			Serial	5926
Permanent link to this record



	Author	Khan, S.U.
	Title	Singlet oxygen-based photoelectrocatalysis : from photosensitizer structures to plasmonic enhancement			Type	Doctoral thesis
	Year	2023	Publication		Abbreviated Journal
	Volume		Issue		Pages	182 p.
	Keywords	Doctoral thesis; Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Singlet molecular oxygen (1O2) has continuously attracted researchers' interest because of its involvement in various processes, such as in photodynamic reactions in biological and chemical systems. 1O2 is an effective electrophile and potent oxidizing agent and can be easily generated by photosensitization via the illumination of organic dyes with visible light. As described in Chapter 1, 1O2 has gained prominence in various applications such as wastewater treatment, photodynamic therapy of cancer, organic synthesis, and recently developed 1O2-based photoelectrochemical (PEC) sensing of phenolic compounds. Phenolic compounds are a potential source of contaminants that originates from industrial effluents and waste products of chemical and pharmaceutical industries. These phenolic compounds pose severe threats to humans and aquatic life after reaching the environment. Therefore, it is imperative to develop photoactive materials that efficiently generate 1O2 and oxidize phenolic compounds and antibiotics. The existing 1O2 generating photosensitizers (PSs) include porphyrins, phthalocyanines (Pcs), subphthalocyanines (SubPcs), and other dyes such as derivatives of xanthene (e.g., Rose Bengal (RB)), and fluorinated boron-dipyrromethene (BODIPYs), and phenothiazinium dyes (e. g. Methylene Blue (MB)) which display long-lived triplet excited state and can be used in 1O2-based applications. This thesis focuses on preparing efficient hybrid materials based on newly synthesized Pcs, different surface area titanium dioxide (TiO2) and plasmonic gold nanoparticles (AuNPs) for their use in the PEC detection of phenolic compounds. The first focus was on developing a fast amperometric method to test the photo-electrocatalytic activity of 1O2 producing PSs dissolved in MeOH based on the redox cycling of an electroactive phenolic compound, hydroquinone (HQ) (Chapter 2). This method of testing PSs does not require the accumulation of a reaction product since the amperometric signal develops near instantly when the light is on, which enables dynamic monitoring of a PSs activity at varying conditions in a single experiment. This method was crucial to measure high 1O2 quantum yield and low yield in the same experimental conditions. Moreover, the obtained results revealed a range of working parameters affecting the PEC activity of PSs. The next goal was to immobilize tert-butyl substituted aluminum Pc (t-BuPcAlCl) on the solid support, which showed a high 1O2 quantum yield. However, before immobilizing Pc on a solid support such as TiO2, it is essential to know the electronic energy level of Pcs for the possible electron transfers from Pcs to TiO2. Therefore, Chapter 3 explored the (spectro)electrochemical properties of t-BuPcAlCl Pc. Next, in Chapter 4, t-BuPcAlCl Pc and other tert-butyl substituted Pcs with Zn central metal, t-BuPcZn, and its metal-free derivative t-BuPcH2 were immobilized on different surface area TiO2. The PEC activity of immobilized Pcs on TiO2 toward different phenols and antibiotics was studied, and the action mechanism was revealed and compared with sterically hindered fluorinated Pc F64PcZn. In the final part of this thesis plasmonic AuNPs were introduced combined with trimethylsilane-protected acetylene functionalized ZnPc (TMSZnPc) to study the synergistic effect that boosts the overall activity toward the detection of phenols under visible light illumination (Chapter 5) . The TMSZnPc was coupled with AuNPs via a click chemistry approach. The 1O2 quantum yield of TMSZnPc improved significantly after conjugating with AuNPs, and, subsequently, the PEC activity for detecting HQ. The theoretical and experimental investigation demonstrated that the plasmonic enhancement of TMSZnPc is driven by the near-field mechanism. This shows the importance of plasmonic AuNPs with other photoactive species for their use in 1O2-based applications. The fundamental knowledge obtained in this doctoral study will ultimately deepen the understanding of developing 1O2-based PEC sensors for detecting phenolic compounds and pharmaceuticals in the wastewater stream, helping to choose efficient materials and, in the last instance, a more sustainable future especially access to clean water for everyone.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:193342			Serial	7337
Permanent link to this record



	Author	Khan, S.U.; Trashin, S.; Beltran, V.; Korostei, Y.S.; Pelmus, M.; Gorun, S.M.; Dubinina, T., V.; Verbruggen, S.W.; De Wael, K.
	Title	Photoelectrochemical behavior of phthalocyanine-sensitized TiO₂ in the presence of electron-shuttling mediators			Type	A1 Journal article
	Year	2022	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	94	Issue	37	Pages	12723-12731
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
	Abstract	Dye-sensitized TiO(2 )has found many applications for dye sensitized solar cells (DSSC), solar-to-chemical energy conversion, water/air purification systems, and (electro)chemical sensors. We report an electrochemical system for testing dye-sensitized materials that can be utilized in photoelectrochemical (PEC) sensors and energy conversion. Unlike related systems, the reported system does not require a direct electron transfer from semiconductors to electrodes. Rather, it relies on electron shuttling by redox mediators. A range of model photocatalytic materials were prepared using three different TiO2 materials (P25, P90, and PC500) and three sterically hindered phthalocyanines (Pcs) with electron-rich tert-butyl substituents (t-Bu4PcZn, t-Bu4PcAlCl, and t-Bu4PcH2). The materials were compared with previously developed TiO(2 )modified by electron-deficient, also sterically hindered fluorinated phthalocyanine F64PcZn, a singlet oxygen (O-1(2)) producer, as well as its metal-free derivative, F64PcH2. The PEC activity depended on the redox mediator, as well as the type of TiO2 and Pc. By comparing the responses of one-electron shuttles, such as K4Fe(CN)(4), and O-1(2)-reactive electron shuttles, such as phenol, it is possible to reveal the action mechanism of the supported photosensitizers, while the overall activity can be assessed using hydroquinone. t-Bu4PcAlCl showed significantly lower blank responses and higher specific responses toward chlorophenols compared to t-Bu4PcZn due to the electron-withdrawing effect of the Al3+ metal center. The combination of reactivity insights and the need for only microgram amounts of sensing materials renders the reported system advantageous for practical applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000855284300001	Publication Date	2022-09-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.4	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 7.4
	Call Number	UA @ admin @ c:irua:190602			Serial	7190
Permanent link to this record



	Author	Khan, S.U.; Trashin, S.A.; Korostei, Y.S.; Dubinina, T.V.; Tomilova, L.G.; Verbruggen, S.W.; De Wael, K.
	Title	Photoelectrochemistry for measuring the photocatalytic activity of soluble photosensitizers			Type	A1 Journal article
	Year	2020	Publication	ChemPhotoChem	Abbreviated Journal
	Volume	4	Issue	4	Pages	300-306
	Keywords	A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	We introduce a rapid method to test the photocatalytic activity of singlet‐oxygen‐producing photosensitizers using a batch cell, a LED laser and a conventional potentiostat. The strategy is based on coupling of photo‐oxidation of hydroquinone and simultaneous electrochemical reduction of its oxidized form at a carbon electrode in an organic solvent (methanol). This scheme gives an immediate response and avoids complications related to long‐term experiments such as oxidative photo‐degradation of photosensitizers and singlet oxygen traps by reactive oxygen species (ROS). Among the tested compounds, a fluoro‐substituted subphthalocyanine showed the highest photocurrent and singlet oxygen quantum yield (ΦΔ) in comparison to phenoxy‐ and tert‐butyl‐substituted analogues, whereas the lowest photocurrents and yields were observed for aggregated and dimeric phthalocyanine complexes. The method is useful for fast screening of the photosensitizing activity and represents the first example of one‐pot coupling of electrochemical and photocatalytic reactions in organic media.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000520100400001	Publication Date	2020-01-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2367-0932	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.7	Times cited	1	Open Access
	Notes	; We gratefully acknowledge the financial support by ERA.Net RUS Plus Plasmon Electrolight project (No. 18-53-76006 ERA) and RSF 17-13-01197. ;			Approved	Most recent IF: 3.7; 2020 IF: NA
	Call Number	UA @ admin @ c:irua:165912			Serial	5771
Permanent link to this record



	Author	Kim, E.; Horckmans, L.; Spooren, J.; Broos, K.; Vrancken, K.C.M.; Quaghebeur, M.
	Title	Recycling of a secondary lead smelting matte by selective citrate leaching of valuable metals and simultaneous recovery of hematite as a secondary resource			Type	A1 Journal article
	Year	2017	Publication	Hydrometallurgy	Abbreviated Journal
	Volume	169	Issue		Pages	290-296
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Anew recycling process, according to the zero-waste concept, was investigated for an iron rich waste stream, more specifically a secondary lead smelting matte. The process consists of a selective citrate leaching of Pb, Cu, Ni and Zn in combination with a roasting step, leading to a simultaneous recovery of hematite as a secondary iron resource. The parameters, such as leaching time, leaching temperature, H2O2 concentration and roasting temperature, were experimentally optimized. The maximum Pb leaching efficiency was 93% and the leachability of Cu (33%) and Zn (11%) increased slightly in the presence of 0.5 M H2O2 in 1 M citrate at 25 degrees C and pH 5.5. Importantly, almost no Fe was leached (< 0.6%) from the iron rich matrix material at this condition allowing for a maximal recovery of hematite as a secondary resource after further treatment (i.e. roasting or sulfur removal). The leachability of Pb, Cu, Ni and Zn was strongly affected by the roasting temperature. Maximum leaching efficiency in 1 M citrate (25 degrees C, L/S ratio 10, pH 6.5) was 93% for Pb, 80% for Cu and 60% for Zn at a roasting temperature of 600 degrees C, while for Ni the maximum leaching efficiency of 53% was reached after roasting at 650 degrees C. Furthermore, when oxidative roasting was applied, the leaching residue consists dominantly of hematite (Fe2O3) with minor quantities of PbSO4, which can be used as pig iron ore (Fe > 60 wt%). (C) 2017 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000401878200035	Publication Date	2017-02-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-386x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:144298			Serial	8463
Permanent link to this record



	Author	Kim, E.; Horckmans, L.; Spooren, J.; Vrancken, K.C.; Quaghebeur, M.; Broos, K.
	Title	Selective leaching of Pb, Cu, Ni and Zn from secondary lead smelting residues			Type	A1 Journal article
	Year	2017	Publication	Hydrometallurgy	Abbreviated Journal
	Volume	169	Issue		Pages	372-381
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Several HNO3-based leaching approaches were tested and optimized to selectively recover Pb and other minor metals (Cu, Ni, Zn) from secondary lead smelter residues (i.e., slag and matte). Firstly, the leaching behaviors of Pb and the matrix element Fe were studied at atmospheric pressure in the temperature range 25-70 degrees C. These elements were present in both materials studied as sulfide and oxide phases. For the sulfur-rich matte residue, the Pb leaching increased from 63% to 69% upon increasing the HNO3 concentration from 0.2 M to 0.5 M. However, by adding Fe(III) as an oxidation agent, Pb leaching from the matte amounted to 90% at 25 degrees C. At a higher temperature, Pb leaching was reduced due to PbSO4 precipitation. In this process, Cu, Zn and Ni leaching was insignificant. For the slag residue, HNO3 could not leach Pb (0.03% Pb leached), while Fe leaching was 19.8% due to a galvanic effect. However, Pb leaching of the slag was 82% in the presence of additional Fe(III). Secondly, to enhance leaching of the other base metals (Cu, Zn and Ni) from the matte, roasting followed by water leaching and (microwave assisted or autoclave) pressurized leaching in 0.5 M HNO3 were applied. During roasting, the FeS phase converted to Fe2O3 above 500 degrees C, and PbS and Pb phases were transformed into insoluble PbSO4 above 400 degrees C. Cu, Ni and Zn leaching was drastically enhanced by a roasting step at 600 degrees C followed by leaching with 0.5 M HNO3 at 50 degrees C, or by pressurized HNO3 leaching above 130 degrees C, whereby Pb leaching almost ceased due to PbSO4 precipitation. During the roasting above 600 degrees C, or microwave assisted extraction (MAE) at 160 degrees C for 15 min, FeS was completely converted to iron oxides that can be used as raw material for pig iron production. Based on the results, the methods investigated can be combined as process steps of two possible routes for the selective recovery of valuable metals and the production of a clean source of Fe oxides from the secondary lead smelting residues studied. (C) 2017 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000401878200045	Publication Date	2017-03-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-386x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:144299			Serial	8503
Permanent link to this record



	Author	Kim, E.; Roosen, J.; Horckmans, L.; Spooren, J.; Broos, K.; Binnemans, K.; Vrancken, K.C.M.; Quaghebeur, M.
	Title	Process development for hydrometallurgical recovery of valuable metals from sulfide-rich residue generated in a secondary lead smelter			Type	A1 Journal article
	Year	2017	Publication	Hydrometallurgy	Abbreviated Journal
	Volume	169	Issue		Pages	589-598
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Two routes were investigated to selectively recover lead and minor metals (Cu, Ni, Zn) from a sulfide-rich lead smelter residue, matte. The first route comprises a two-step leaching process that combines Fe(III)-HNO3 leaching with roasting, followed by water leaching. In the first step, the efficiency of Pb leaching was 90% at the optimum condition (L/S ratio 8, 0.5 mol.L-1 HNO3, 0.15 mol.L-1 Fe(III), 25 degrees C). In the second step, roasting at 600 degrees C followed by water leaching at 50 degrees C selectively leached Ni, Cu, and Zn while fully converting iron sulfides to oxides. One-step oxidative pressure leaching in HNO3 was investigated as an alternative to simultaneously leach Pb, Cu, Ni and Zn. At the optimal conditions (130 degrees C, 60 min, 0.3 mol.L-1 HNO3, 0.07 mol.L-1 Fe(III), L/S ratio 20), Pb, Cu, Zn and Ni leaching were 92, 60, 70 and 66%, respectively, while Fe leaching remained low (2%). The leachates obtained from both leaching routes were treated by ion-exchange adsorption with diethylenetriaminepentaacetic acid (DTPA) functionalized chitosan-silica hybrid materials to investigate the selective recovery of Cu, Zn and Ni. The adsorption order appeared to be in the same order as the corresponding stability constants for complexes between the respective metal ions and free DTPA: Ca(II) < Zn(II) < Pb (II) approximate to Ni(II) < Cu(II). This allows not only to selectively recover Cu, Zn and Ni from the leachates, but also to mutually separate them by using the functionalized resin as a stationary phase in column chromatography. To avoid adsorbent contamination, Fe(III) and Pb(II) may be removed from the leachates in a pre-treatment step. Based on these results, the investigated methods can be combined as process steps of two possible routes for the selective recovery of valuable metals from the studied secondary lead smelting residue. The two-step leaching process seems to be superior since a more concentrated solution of Cu, Ni, and Zn is produced in the 2nd leaching step with low capital cost.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000401878200070	Publication Date	2017-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-386x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:144300			Serial	8414
Permanent link to this record



	Author	Kim, E.; Spooren, J.; Broos, K.; Horckmans, L.; Quaghebeur, M.; Vrancken, K.C.
	Title	Selective recovery of Cr from stainless steel slag by alkaline roasting followed by water leaching			Type	A1 Journal article
	Year	2015	Publication	Hydrometallurgy	Abbreviated Journal
	Volume	158	Issue		Pages	139-148
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	Selective chromium (Cr) leaching from stainless steel slag (SS slag) by alkali roasting followed by water leaching was investigated. The efficiency of the alkali roasting process for Cr leaching was increased by optimizing the mass ratio of alkaline agents (NaOH, and NaOH-NaNO3) to the slag, roasting temperature and time. At the optimum condition (0.67 mass ratio of NaOH to SS slag, 400 degrees C, 2 h) of NaOH roasting, chromium leaching was around 83%, while the matrix material was dissolved only to a limited extent (Si 8.0%). Mechanical activation of the SS slag prior to roasting reduced the optimum NaOH to SS slag mass ratio to 0.4. The addition of NaNO3 as an oxidant to the NaOH salt increased Cr leaching to 89% after roasting at 400 degrees C for 2 h. The remaining Cr phases in the residue were almost exclusively FeCr alloys. Further chromium dissolution from these alloys is prevented by a passivation layer of Fe oxides as shown by SEM/EDS images. Based on these results, a SS slag recycling process is suggested in which roasting-water leaching followed by water washing to remove Cr yields a residue which has potential for application as a construction material. (C) 2015 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000366768000019	Publication Date	2015-11-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-386x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:130223			Serial	8504
Permanent link to this record



	Author	Kim, E.; Spooren, J.; Broos, K.; Nielsen, P.; Horckmans, L.; Geurts, R.; Vrancken, K.C.; Quaghebeur, M.
	Title	Valorization of stainless steel slag by selective chromium recovery and subsequent carbonation of the matrix material			Type	A1 Journal article
	Year	2016	Publication	Journal of cleaner production	Abbreviated Journal
	Volume	117	Issue		Pages	221-228
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	This study focuses on the recycling of stainless steel (SS) slags containing about 1.2 wt% of chromium (Cr). The selective recovery of Cr from SS slag by a hydrometallurgical method (alkaline pressure leaching) was investigated. Leaching experiments were carried out based on 2(4-1) factorial design of experiment (DOE) with the following parameters: NaOH concentration, temperature, leaching time, and mechanical activation (MA). Results show that temperature and MA are the most influencing factors for an enhanced Cr leaching. The maximum Cr leaching was 46% at 1 M NaOH, 240 degrees C, 6 h, MA 30 min, while the matrix material was dissolved only to a limited extent (Al 2.88%, Si 0.12%, Ca 0.05%). After Cr leaching followed by alkali washing, a carbonation treatment is proposed to stabilize the remaining Cr in the matrix material and make the subsequent recycling of the matrix material as a construction material possible. (C) 2016 Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000371552200025	Publication Date	2016-01-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0959-6526	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:132432			Serial	8731
Permanent link to this record



	Author	Kim, E.; Spooren, J.; Broos, K.; Nielsen, P.; Horckmans, L.; Vrancken, K.C.; Quaghebeur, M.
	Title	New method for selective Cr recovery from stainless steel slag by NaOCl assisted alkaline leaching and consecutive BaCrO₄ precipitation			Type	A1 Journal article
	Year	2016	Publication	Chemical engineering journal	Abbreviated Journal
	Volume	295	Issue		Pages	542-551
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	A new hydrometallurgical method was investigated for selective leaching of chromium from stainless steel slag (SS slag) consisting of temperature controlled extraction with NaOH in the presence of NaOCl, followed by water leaching. After parameter optimization of the NaOCl-NaOH extraction step, a selective Cr leaching of 68% was reached, while dissolution of matrix materials was low (Al 0.3%, Ca 2.0%, Si 0.4%). The optimum conditions for the investigated system are: 105 degrees C, 6 h, SS slag particle size <63 mu m, mass ratio of NaOH to SS slag 0.13, and 3.3 mmol NaOCl to 1 g SS slag. The described oxidative alkaline leaching process by hypochlorite enables selective recovery of Cr at a significantly lower temperature and required amount of alkaline agent than molten salt or alkaline roasting processes. BaCrO4 was precipitated to purify and concentrate Cr from the leachate in which also minor amounts of Mn and V were present. This method allowed for a 99.9% Cr recovery rate. The obtained leaching residue shows no alterations of the SS slag's mineralogy with respect to untreated material. Therefore, a known carbonation treatment of the slag can be applied to prepare novel construction materials with a lowered Cr content. (C) 2016 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000375507300059	Publication Date	2016-03-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1385-8947; 1873-3212	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:133632			Serial	8302
Permanent link to this record



	Author	Koch, K.; Samson, R.; Denys, S.
	Title	Experimental and computational aerodynamic characterisation of urban trees			Type	A1 Journal article
	Year	2020	Publication	Biosystems Engineering	Abbreviated Journal	Biosyst Eng
	Volume	190	Issue		Pages	47-57
	Keywords	A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	The Darcy–Forchheimer method is used for modelling the airflow through vegetation. Seven tree and shrub species with contrasting leaf morphologies were installed in a wind tunnel to allow pressure loss measurements across the plant section. Aerodynamic parameters derived from this experiment were inserted into a COMSOL Multiphysics computational fluid dynamics model. The model was confirmed to be a good predictor for airflow through vegetation (R2 = 0.98), regardless of plant morphology. Moreover, supplementing these data with results from a previous study (which considered herbaceous species) revealed a pattern of pressure loss data, that was already been normalised for plant area density. Although we propose further research into kinetic energy transfer in vegetation, this study provides sufficient interesting information for further applications and modelling to describe and predict urban ecology.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000512221700005	Publication Date	2019-12-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1537-5110	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.1	Times cited		Open Access
	Notes	; This work was supported by the VLAIO-VIS project 'Green building: green walls for sustainable buildings and cities' (140993) and the FWO-SBO project 'EcoCities: Green roofs and walls as a source for ecosystem services in future cities' (S002818N). ;			Approved	Most recent IF: 5.1; 2020 IF: 2.044
	Call Number	UA @ admin @ c:irua:164883			Serial	6516
Permanent link to this record