154 results on '"Krol, R"'
Search Results
2. Application of EUS or MRCP prior to ERCP in patients with suspected choledocholithiasis in clinical practice.
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de Jong MJP, Engels MML, Sperna Weiland C, Krol R, Bisseling TM, van Geenen EM, Siersema P, van Delft F, and van Hooft JE
- Abstract
Background and study aims Patients with symptomatic cholelithiasis can be stratified according to the 2019 European Society for Gastrointestinal Endoscopy (ESGE) guideline into low-, intermediate- and high-likelihood groups for presence of choledocholithiasis. For the intermediate group, endoscopic ultrasound (EUS) or magnetic resonance cholangiopancreatography (MRCP) is recommended to assess whether an endoscopic retrograde cholangiopancreatography (ERCP) is necessary prior to cholecystectomy. The aim of the study was to investigate adherence to the guideline for diagnostic and treatment strategy for cholelithiasis in daily clinical practice. Patients and methods A multicenter, retrospective cross-sectional observational study of the diagnostic pathway of patients with suspicion of choledocholithiasis was conducted between 2019 and 2021. Patients were stratified according to the ESGE guideline "Endoscopic management of common bile duct stones". Results A total of 305 patients were included in the analysis and stratified into low- (17%), intermediate- (40%) and high- (43%) likelihood of choledocholithiasis. In these three categories, 182 patients (60%) underwent ERCP. Adherence to the ESGE guideline recommendation was 59.7% overall and was the highest in the intermediate-likelihood group (83.6%), compared with 45.1% in the low- and 43.2% in the high-likelihood group, respectively ( P < 0.001). In the high-likelihood group, 49% underwent additional imaging. In 195 patients who underwent additional imaging, 55 ERCPs (28.2%) could be avoided. Conclusions This study shows that stratification according to the ESGE guideline is useful to reduce the number of unnecessary additional imaging procedures and ERCPs in patients with a suspicion of choledocholithiasis. It seems worthwhile to perform EUS prior to ERCP in the same session., Competing Interests: Conflict of Interest Mike J.P. de Jong, Megan M.L. Engels, Christina J. Sperna Weiland, Robin Krol, Tanya M. Bisseling and Foke van Delft have no conflicts of interest or financial ties to disclose. Jeanin E. van Hooft reports lecture fees from Cook Medical, dr. Falk Pharma, Boston Scientific, AbbVie, and consultancy fees from Olympus. Erwin M. van Geenen reports research grants from Olympus, Boston Scientific, and MTW Endoskopie. Peter D. Siersema reports research grants from Pentax and Fujifilm. All outside the submitted work., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).)
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- 2025
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3. Assessing elevated pressure impact on photoelectrochemical water splitting via multiphysics modeling.
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Liang F, van de Krol R, and Abdi FF
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Photoelectrochemical (PEC) water splitting is a promising approach for sustainable hydrogen production. Previous studies have focused on devices operated at atmospheric pressure, although most applications require hydrogen delivered at elevated pressure. Here, we address this critical gap by investigating the implications of operating PEC water splitting directly at elevated pressure. We evaluate the benefits and penalties associated with elevated pressure operation by developing a multiphysics model that incorporates empirical data and direct experimental observations. Our analysis reveals that the operating pressure influences bubble characteristics, product gas crossover, bubble-induced optical losses, and concentration overpotential, which are crucial for the overall device performance. We identify an optimum pressure range of 6-8 bar for minimizing losses and achieving efficient PEC water splitting. This finding provides valuable insights for the design and practical implementation of PEC water splitting devices, and the approach can be extended to other gas-producing (photo)electrochemical systems. Overall, our study demonstrates the importance of elevated pressure in PEC water splitting, enhancing the efficiency and applicability of green hydrogen generation., (© 2024. The Author(s).)
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- 2024
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4. Electrolyte selection toward efficient photoelectrochemical glycerol oxidation on BiVO 4 .
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Kong H, Gupta S, Pérez-Torres AF, Höhn C, Bogdanoff P, Mayer MT, van de Krol R, Favaro M, and Abdi FF
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Glycerol, a primary by-product of biodiesel production, can be oxidized into various value-added chemicals, significantly enhancing the techno-economic value of photoelectrochemical (PEC) cells. Several studies have explored various photoelectrode materials and co-catalysts, but the influence of electrolytes on PEC glycerol oxidation has remained relatively unexplored despite its significance. Here, we explore the impact of various acidic (pH = 2) electrolytes, namely NaNO
3 , NaClO4 , Na2 SO4 , K2 SO4 , and KPi , on PEC glycerol oxidation using nanoporous thin film BiVO4 as a model photoanode. Our experimental findings reveal that the choice of electrolyte anion and cation significantly affects the PEC performance ( i.e. , photocurrent, onset potential, stability, and selectivity towards value-added products) of BiVO4 for glycerol oxidation. To explain this interesting phenomenon, we correlate the observed performance trend with the ion specificity in the Hofmeister series as well as the buffering capacity of the electrolytes. Notably, NaNO3 is identified as the optimal electrolyte for PEC glycerol oxidation with BiVO4 when considering various factors such as stability and production rates for glycerol oxidation reaction (GOR) products, surpassing the previously favored Na2 SO4 . Glycolaldehyde emerges as the most dominant product with ∼50% selectivity in NaNO3 . The general applicability of our findings is confirmed by similar observation in electrochemical (EC) GOR with a polycrystalline platinum anode. Overall, these results emphasize the critical role of electrolyte selection in enhancing the efficiency of EC/PEC glycerol oxidation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2024
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5. Unraveling Electron Dynamics in p-type Indium Phosphide (100): A Time-Resolved Two-Photon Photoemission Study.
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Diederich J, Velasquez Rojas J, Zare Pour MA, Ruiz Alvarado IA, Paszuk A, Sciotto R, Höhn C, Schwarzburg K, Ostheimer D, Eichberger R, Schmidt WG, Hannappel T, van de Krol R, and Friedrich D
- Abstract
Renewable ("green") hydrogen production through direct photoelectrochemical (PEC) water splitting is a potential key contributor to the sustainable energy mix of the future. We investigate the potential of indium phosphide (InP) as a reference material among III-V semiconductors for PEC and photovoltaic (PV) applications. The p(2 × 2)/c(4 × 2)-reconstructed phosphorus-terminated p-doped InP(100) (P-rich p-InP) surface is the focus of our investigation. We employ time-resolved two-photon photoemission (tr-2PPE) spectroscopy to study electronic states near the band gap with an emphasis on normally unoccupied conduction band states that are inaccessible through conventional single-photon emission methods. The study shows the complexity of the p-InP electronic band structure and reveals the presence of at least nine distinct states between the valence band edge and vacuum energy, including a valence band state, a surface defect state pinning the Fermi level, six unoccupied surface resonances within the conduction band, as well as a cluster of states about 1.6 eV above the CBM, identified as a bulk-to-surface transition. Furthermore, we determined the decay constants of five of the conduction band states, enabling us to track electron relaxation through the bulk and surface conduction bands. This comprehensive understanding of the electron dynamics in p-InP(100) lays the foundation for further exploration and surface engineering to enhance the properties and applications of p-InP-based III-V-compounds for, e.g. , efficient and cost-effective PEC hydrogen production and highly efficient PV cells.
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- 2024
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6. Solar-driven upgrading of biomass by coupled hydrogenation using in situ (photo)electrochemically generated H 2 .
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Obata K, Schwarze M, Thiel TA, Zhang X, Radhakrishnan B, Ahmet IY, van de Krol R, Schomäcker R, and Abdi FF
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With the increasing pressure to decarbonize our society, green hydrogen has been identified as a key element in a future fossil fuel-free energy infrastructure. Solar water splitting through photoelectrochemical approaches is an elegant way to produce green hydrogen, but for low-value products like hydrogen, photoelectrochemical production pathways are difficult to be made economically competitive. A possible solution is to co-produce value-added chemicals. Here, we propose and demonstrate the in situ use of (photo)electrochemically generated H
2 for the homogeneous hydrogenation of itaconic acid-a biomass-derived feedstock-to methyl succinic acid. Coupling these two processes offers major advantages in terms of stability and reaction flexibility compared to direct electrochemical hydrogenation, while minimizing the overpotential. An overall conversion of up to ~60% of the produced hydrogen is demonstrated for our coupled process, and a techno-economic assessment of our proposed device further reveals the benefit of coupling solar hydrogen production to a chemical transformation., (© 2023. Springer Nature Limited.)- Published
- 2023
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7. Technological Pathways to Produce Compressed and Highly Pure Hydrogen from Solar Power.
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Ivanova ME, Peters R, Müller M, Haas S, Seidler MF, Mutschke G, Eckert K, Röse P, Calnan S, Bagacki R, Schlatmann R, Grosselindemann C, Schäfer LA, Menzler NH, Weber A, van de Krol R, Liang F, Abdi FF, Brendelberger S, Neumann N, Grobbel J, Roeb M, Sattler C, Duran I, Dietrich B, Hofberger MEC, Stoppel L, Uhlenbruck N, Wetzel T, Rauner D, Hecimovic A, Fantz U, Kulyk N, Harting J, and Guillon O
- Abstract
Hydrogen (H
2 ) produced from renewables will have a growing impact on the global energy dynamics towards sustainable and carbon-neutral standards. The share of green H2 is still too low to meet the net-zero target, while the demand for high-quality hydrogen continues to rise. These factors amplify the need for economically viable H2 generation technologies. The present article aims at evaluating the existing technologies for high-quality H2 production based on solar energy. Technologies such as water electrolysis, photoelectrochemical and solar thermochemical water splitting, liquid metal reactors and plasma conversion utilize solar power directly or indirectly (as carbon-neutral electrons) and are reviewed from the perspective of their current development level, technical limitations and future potential., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)- Published
- 2023
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8. Life cycle net energy assessment of sustainable H 2 production and hydrogenation of chemicals in a coupled photoelectrochemical device.
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Zhang X, Schwarze M, Schomäcker R, van de Krol R, and Abdi FF
- Abstract
Green hydrogen has been identified as a critical enabler in the global transition to sustainable energy and decarbonized society, but it is still not economically competitive compared to fossil-fuel-based hydrogen. To overcome this limitation, we propose to couple photoelectrochemical (PEC) water splitting with the hydrogenation of chemicals. Here, we evaluate the potential of co-producing hydrogen and methyl succinic acid (MSA) by coupling the hydrogenation of itaconic acid (IA) inside a PEC water splitting device. A negative net energy balance is predicted to be achieved when the device generates only hydrogen, but energy breakeven can already be achieved when a small ratio (~2%) of the generated hydrogen is used in situ for IA-to-MSA conversion. Moreover, the simulated coupled device produces MSA with much lower cumulative energy demand than conventional hydrogenation. Overall, the coupled hydrogenation concept offers an attractive approach to increase the viability of PEC water splitting while at the same time decarbonizing valuable chemical production., (© 2023. The Author(s).)
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- 2023
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9. Kinetic investigation of para -nitrophenol reduction with photodeposited platinum nanoparticles onto tunicate cellulose.
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Thiel TA, Zhang X, Radhakrishnan B, van de Krol R, Abdi FF, Schroeter M, Schomäcker R, and Schwarze M
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Photodeposition is a specific method for depositing metallic co-catalysts onto photocatalysts and was applied for immobilizing platinum nanoparticles onto cellulose, a photocatalytically inactive biopolymer. The obtained Pt@cellulose catalysts show narrow and well-dispersed nanoparticles with average sizes between 2 and 5 nm, whereby loading, size and distribution depend on the preparation conditions. The catalysts were investigated for the hydrogenation of para -nitrophenol via transfer hydrogenation using sodium borohydride as the hydrogen source, and the reaction rate constant was determined using the pseudo-first-order reaction rate law. The Pt@cellulose catalysts are catalytically active with rate constant values k from 0.09 × 10
-3 to 0.43 × 10-3 min-1 , which were higher than the rate constant of a commercial Pt@Al2 O3 catalyst ( k = 0.09 × 10-3 min-1 ). Additionally, the Pt@cellulose catalyst can be used for electrochemical hydrogenation of para -nitrophenol where the hydrogen is electrocatalytically formed. The electrochemical hydrogenation is faster compared to the transfer hydrogenation ( k = 0.11 min-1 )., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)- Published
- 2022
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10. Constitutional isomerism of the linkages in donor-acceptor covalent organic frameworks and its impact on photocatalysis.
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Yang J, Ghosh S, Roeser J, Acharjya A, Penschke C, Tsutsui Y, Rabeah J, Wang T, Djoko Tameu SY, Ye MY, Grüneberg J, Li S, Li C, Schomäcker R, Van De Krol R, Seki S, Saalfrank P, and Thomas A
- Abstract
When new covalent organic frameworks (COFs) are designed, the main efforts are typically focused on selecting specific building blocks with certain geometries and properties to control the structure and function of the final COFs. The nature of the linkage (imine, boroxine, vinyl, etc.) between these building blocks naturally also defines their properties. However, besides the linkage type, the orientation, i.e., the constitutional isomerism of these linkages, has rarely been considered so far as an essential aspect. In this work, three pairs of constitutionally isomeric imine-linked donor-acceptor (D-A) COFs are synthesized, which are different in the orientation of the imine bonds (D-C=N-A (DCNA) and D-N=C-A (DNCA)). The constitutional isomers show substantial differences in their photophysical properties and consequently in their photocatalytic performance. Indeed, all DCNA COFs show enhanced photocatalytic H
2 evolution performance than the corresponding DNCA COFs. Besides the imine COFs shown here, it can be concluded that the proposed concept of constitutional isomerism of linkages in COFs is quite universal and should be considered when designing and tuning the properties of COFs., (© 2022. The Author(s).)- Published
- 2022
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11. Low-bias photoelectrochemical water splitting via mediating trap states and small polaron hopping.
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Wu H, Zhang L, Du A, Irani R, van de Krol R, Abdi FF, and Ng YH
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Metal oxides are promising for photoelectrochemical (PEC) water splitting due to their robustness and low cost. However, poor charge carrier transport impedes their activity, particularly at low-bias voltage. Here we demonstrate the unusual effectiveness of phosphorus doping into bismuth vanadate (BiVO
4 ) photoanode for efficient low-bias PEC water splitting. The resulting BiVO4 photoanode shows a separation efficiency of 80% and 99% at potentials as low as 0.6 and 1.0 VRHE , respectively. Theoretical simulation and experimental analysis collectively verify that the record performance originates from the unique phosphorus-doped BiVO4 configuration with concurrently mediated carrier density, trap states, and small polaron hopping. With NiFeOx cocatalyst, the BiVO4 photoanode achieves an applied bias photon-to-current efficiency of 2.21% at 0.6 VRHE . The mechanistic understanding of the enhancement of BiVO4 properties provides key insights in trap state passivation and polaron hopping for most photoactive metal oxides., (© 2022. The Author(s).)- Published
- 2022
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12. Influence of Excess Charge on Water Adsorption on the BiVO 4 (010) Surface.
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Wang W, Favaro M, Chen E, Trotochaud L, Bluhm H, Choi KS, van de Krol R, Starr DE, and Galli G
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We present a combined computational and experimental study of the adsorption of water on the Mo-doped BiVO
4 (010) surface, revealing how excess electrons influence the dissociation of water and lead to hydroxyl-induced alterations of the surface electronic structure. By comparing ambient pressure resonant photoemission spectroscopy (AP-ResPES) measurements with the results of first-principles calculations, we show that the dissociation of water on the stoichiometric Mo-doped BiVO4 (010) surface stabilizes the formation of a small electron polaron on the VO4 tetrahedral site and leads to an enhanced concentration of localized electronic charge at the surface. Our calculations demonstrate that the dissociated water accounts for the enhanced V4+ signal observed in ambient pressure X-ray photoelectron spectroscopy and the enhanced signal of a small electron polaron inter-band state observed in AP-ResPES measurements. For ternary oxide surfaces, which may contain oxygen vacancies in addition to other electron-donating dopants, our study reveals the importance of defects in altering the surface reactivity toward water and the concomitant water-induced modifications to the electronic structure.- Published
- 2022
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13. Quantification of the Activator and Sensitizer Ion Distributions in NaYF 4 :Yb 3+ , Er 3+ Upconverting Nanoparticles Via Depth-Profiling with Tender X-Ray Photoemission.
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Clark PCJ, Andresen E, Sear MJ, Favaro M, Girardi L, van de Krol R, Resch-Genger U, and Starr DE
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- Cations, Luminescence, Photoelectron Spectroscopy, X-Rays, Erbium chemistry, Fluorides chemistry, Nanoparticles chemistry, Ytterbium chemistry, Yttrium chemistry
- Abstract
The spatial distribution and concentration of lanthanide activator and sensitizer dopant ions are of key importance for the luminescence color and efficiency of upconverting nanoparticles (UCNPs). Quantifying dopant ion distributions and intermixing, and correlating them with synthesis methods require suitable analytical techniques. Here, X-ray photoelectron spectroscopy depth-profiling with tender X-rays (2000-6000 eV), providing probe depths ideally matched to UCNP sizes, is used to measure the depth-dependent concentration ratios of Er
3+ to Yb3+ , [Er3+ ]/[Yb3+ ], in three types of UCNPs prepared using different reagents and synthesis methods. This is combined with data simulations and inductively coupled plasma-optical emission spectroscopy (ICP-OES) measurements of the lanthanide ion concentrations to construct models of the UCNPs' dopant ion distributions. The UCNP sizes and architectures are chosen to demonstrate the potential of this approach. Core-only UCNPs synthesized with XCl3 ·6H2 O precursors (β-phase) exhibit a homogeneous distribution of lanthanide ions, but a slightly surface-enhanced [Er3+ ]/[Yb3+ ] is observed for UCNPs prepared with trifluroacetate precursors (α-phase). Examination of Yb-core@Er-shell UCNPs reveals a co-doped, intermixed region between the single-doped core and shell. The impact of these different dopant ion distributions on the UCNP's optical properties is discussed to highlight their importance for UCNP functionality and the design of efficient UCNPs., (© 2022 The Authors. Small published by Wiley-VCH GmbH.)- Published
- 2022
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14. Activating a Semiconductor-Liquid Junction via Laser-Derived Dual Interfacial Layers for Boosted Photoelectrochemical Water Splitting.
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Jian J, Wang S, Ye Q, Li F, Su G, Liu W, Qu C, Liu F, Li C, Jia L, Novikov AA, Vinokurov VA, Harvey DHS, Shchukin D, Friedrich D, van de Krol R, and Wang H
- Abstract
The semiconductor-liquid junction (SCLJ), the dominant place in photoelectrochemical (PEC) catalysis, determines the interfacial activity and stability of photoelectrodes, whcih directly affects the viability of PEC hydrogen generation. Though efforts dedicated in past decades, a challenge remains regarding creating a synchronously active and stable SCLJ, owing to the technical hurdles of simultaneously overlaying the two advantages. The present work demonstrates that creating an SCLJ with a unique configuration of the dual interfacial layers can yield BiVO
4 photoanodes with synchronously boosted photoelectrochemical activity and operational stability, with values located at the top in the records of such photoelectrodes. The bespoke dual interfacial layers, accessed via grafting laser-generated carbon dots with phenolic hydroxyl groups (LGCDs-PHGs), are experimentally verified effective, not only in generating the uniform layer of LGCDs with covalent anchoring for inhibited photocorrosion, but also in activating, respectively, the charge separation and transfer in each layer for boosted charge-carrier kinetics, resulting in FeNiOOH-LGCDs-PHGs-MBVO photoanodes with a dual configuration with the photocurrent density of 6.08 mA cm-2 @ 1.23 VRHE , and operational stability up to 120 h @ 1.23 VRHE . Further work exploring LGCDs-PHGs from catecholic molecules warrants the proposed strategy as being a universal alternative for addressing the interfacial charge-carrier kinetics and operational stability of semiconductor photoelectrodes., (© 2022 Wiley-VCH GmbH.)- Published
- 2022
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15. Photocatalytic hydrogenation of acetophenone on a titanium dioxide cellulose film.
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Thiel TA, Obata K, Abdi FF, van de Krol R, Schomäcker R, and Schwarze M
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A previously developed sustainable immobilization concept for photocatalysts based on cellulose as a renewable support material was applied for the photocatalytic hydrogenation of acetophenone (ACP) to 1-phenyl ethanol (PE). Four different TiO
2 modifications (P25, P90, PC105, and PC500) were screened for the reaction showing good performance for PC25 and PC500. PC500 was selected for a detailed kinetic study to find the optimal operating conditions, and to obtain a better understanding of the photocatalytic pathway in relation to conventional and transfer hydrogenation. The kinetic data were analyzed using the pseudo-first-order reaction rate law. A complete conversion was obtained for ACP concentrations below 1 mM using a 360 nm filter and argon as the purge gas within 2-3 hours. High oxygen concentrations slow down or prevent the reaction, and wavelengths below 300 nm lead to side-products. By investigating the temperature dependency, an activation energy of 22 kJ mol-1 was determined which is lower than the activation energies for conventional and transfer hydrogenation, because the light activation of the photocatalyst turns the endothermic to an exothermic reaction. PC500 was immobilized onto the cellulose film showing a 37% lower activity that remains almost constant after multiple use., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)- Published
- 2022
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16. Author Correction: Extraction of mobile charge carrier photogeneration yield spectrum of ultrathin-film metal oxide photoanodes for solar water splitting.
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Grave DA, Ellis DS, Piekner Y, Kölbach M, Dotan H, Kay A, Schnell P, van de Krol R, Abdi FF, Friedrich D, and Rothschild A
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- 2021
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17. Protonated Imine-Linked Covalent Organic Frameworks for Photocatalytic Hydrogen Evolution.
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Yang J, Acharjya A, Ye MY, Rabeah J, Li S, Kochovski Z, Youk S, Roeser J, Grüneberg J, Penschke C, Schwarze M, Wang T, Lu Y, van de Krol R, Oschatz M, Schomäcker R, Saalfrank P, and Thomas A
- Abstract
Covalent organic frameworks (COFs) have emerged as an important class of organic semiconductors and photocatalysts for the hydrogen evolution reaction (HER)from water. To optimize their photocatalytic activity, typically the organic moieties constituting the frameworks are considered and the most suitable combinations of them are searched for. However, the effect of the covalent linkage between these moieties on the photocatalytic performance has rarely been studied. Herein, we demonstrate that donor-acceptor (D-A) type imine-linked COFs can produce hydrogen with a rate as high as 20.7 mmol g
-1 h-1 under visible light irradiation, upon protonation of their imine linkages. A significant red-shift in light absorbance, largely improved charge separation efficiency, and an increase in hydrophilicity triggered by protonation of the Schiff-base moieties in the imine-linked COFs, are responsible for the improved photocatalytic performance., (© 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)- Published
- 2021
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18. Extraction of mobile charge carrier photogeneration yield spectrum of ultrathin-film metal oxide photoanodes for solar water splitting.
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Grave DA, Ellis DS, Piekner Y, Kölbach M, Dotan H, Kay A, Schnell P, van de Krol R, Abdi FF, Friedrich D, and Rothschild A
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Light absorption in strongly correlated electron materials can excite electrons and holes into a variety of different states. Some of these excitations yield mobile charge carriers, whereas others result in localized states that cannot contribute to photocurrent. The photogeneration yield spectrum, ξ(λ), represents the wavelength-dependent ratio between the contributing absorption that ultimately generates mobile charge carriers and the overall absorption. Despite being a vital material property, it is not trivial to characterize. Here, we present an empirical method to extract ξ(λ) through optical and external quantum efficiency measurements of ultrathin films. We applied this method to haematite photoanodes for water photo-oxidation, and observed that it is self-consistent for different illumination conditions and applied potentials. We found agreement between the extracted ξ(λ) spectrum and the photoconductivity spectrum measured by time-resolved microwave conductivity. These measurements revealed that mobile charge carrier generation increases with increasing energy across haematite's absorption spectrum. Low-energy non-contributing absorption fundamentally limits the photoconversion efficiency of haematite photoanodes and provides an upper limit to the achievable photocurrent that is substantially lower than that predicted based solely on absorption above the bandgap. We extended our analysis to TiO
2 and BiVO4 photoanodes, demonstrating the broader utility of the method for determining ξ(λ).- Published
- 2021
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19. On the Origin of the OER Activity of Ultrathin Manganese Oxide Films.
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Plate P, Höhn C, Bloeck U, Bogdanoff P, Fiechter S, Abdi FF, van de Krol R, and Bronneberg AC
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There is an urgent need for cheap, stable, and abundant catalyst materials for photoelectrochemical water splitting. Manganese oxide is an interesting candidate as an oxygen evolution reaction (OER) catalyst, but the minimum thickness above which MnO
x thin films become OER-active has not yet been established. In this work, ultrathin (<10 nm) manganese oxide films are grown on silicon by atomic layer deposition to study the origin of OER activity under alkaline conditions. We found that MnOx films thinner than 1.5 nm are not OER-active. X-ray photoelectron spectroscopy shows that this is due to electrostatic catalyst-support interactions that prevent the electrochemical oxidation of the manganese ions close to the interface with the support, while in thicker films, MnIII and MnIV oxide layers appear as OER-active catalysts after oxidation and electrochemical treatment. From our investigations, it can be concluded that one MnIII,IV -O monolayer is sufficient to establish oxygen evolution under alkaline conditions. The results of this study provide important new design criteria for ultrathin manganese oxide oxygen evolution catalysts.- Published
- 2021
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20. Different Photostability of BiVO 4 in Near-pH-Neutral Electrolytes.
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Zhang S, Ahmet I, Kim SH, Kasian O, Mingers AM, Schnell P, Kölbach M, Lim J, Fischer A, Mayrhofer KJJ, Cherevko S, Gault B, van de Krol R, and Scheu C
- Abstract
Photoelectrochemical water splitting is a promising route to produce hydrogen from solar energy. However, corrosion of photoelectrodes remains a fundamental challenge for their implementation. Here, we reveal different dissolution behaviors of BiVO
4 photoanode in pH-buffered borate, phosphate, and citrate (hole-scavenger) electrolytes, studied in operando employing an illuminated scanning flow cell. We demonstrate that decrease in photocurrents alone does not reflect the degradation of photoelectrodes. Changes in dissolution rates correlate to the evolution of surface chemistry and morphology. The correlative measurements on both sides of the liquid-semiconductor junction provide quantitative comparison and mechanistic insights into the degradation processes., Competing Interests: The authors declare no competing financial interest., (© 2020 American Chemical Society.)- Published
- 2020
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21. Tests of Belt Linear Speed for Identification of Frictional Contact Phenomena.
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Bortnowski P, Gladysiewicz L, Krol R, and Ozdoba M
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In the locations where driving forces are transmitted, the changing tensile forces cause rapid elastic deformations of the belt. The deformation changes the belt speed. Measurement of the belt speed on the friction contact sections is essential to identify elastic slippage. However, the scale of the phenomenon is small, so it is necessary to use precise measuring equipment. The article presents measurements of the linear belt speed with the use of various sensors and measuring devices. A measurement error was determined for each of the presented measurement methods. The method with the highest accuracy was used to identify the elastic slippage on the drive pulley.
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- 2020
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22. Revealing the relationship between photoelectrochemical performance and interface hole trapping in CuBi 2 O 4 heterojunction photoelectrodes.
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Song A, Levine I, van de Krol R, Dittrich T, and Berglund SP
- Abstract
p-Type CuBi
2 O4 is considered a promising metal oxide semiconductor for large-scale, economic solar water splitting due to the optimal band structure and low-cost fabrication. The main challenge in utilizing CuBi2 O4 as a photoelectrode for water splitting, is that it must be protected from photo-corrosion in aqueous solutions, an inherent problem for Cu-based metal oxide photoelectrodes. In this work, several buffer layers (CdS, BiVO4 , and Ga2 O3 ) were tested between CuBi2 O4 and conformal TiO2 as the protection layer. RuOx was used as the co-catalyst for hydrogen evolution. Factors that limit the photoelectrochemical performance of the CuBi2 O4 /TiO2 /RuOx , CuBi2 O4 /CdS/TiO2 /RuOx , CuBi2 O4 /BiVO4 /TiO2 /RuOx and CuBi2 O4 /Ga2 O3 /TiO2 /RuOx heterojunction photoelectrodes were revealed by comparing photocurrents, band offsets, and directed charge transfer measured by modulated surface photovoltage spectroscopy. For CuBi2 O4 /Ga2 O3 /TiO2 /RuOx photoelectrodes, barriers for charge transfer strongly limited the performance. In CuBi2 O4 /CdS/TiO2 /RuOx , the absence of hole traps resulted in a relatively high photocurrent density and faradaic efficiency for hydrogen evolution despite the presence of pronounced deep defect states at the CuBi2 O4 /CdS interface. Hole trapping limited the performance moderately in CuBi2 O4 /BiVO4 /TiO2 /RuOx and strongly in CuBi2 O4 /TiO2 /RuOx photoelectrodes. For the first time, our results show that hole trapping is a key factor that must be addressed to optimize the performance of CuBi2 O4 -based heterojunction photoelectrodes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2020
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23. The expression profile of genes encoding tumor necrosis factor-alpha, interleukin-6 and their receptor in benign adrenal tumors.
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Morawiec E, Cholewa K, Zenderowski M, Batoryna O, Waluga-Kozlowska E, Komosinska-Vassev K, Krol R, Kajor M, Olczyk P, and Waluga M
- Subjects
- Adrenal Gland Neoplasms complications, Aged, Cushing Syndrome etiology, Female, Gene Expression Profiling, Humans, Hyperaldosteronism etiology, Male, Middle Aged, Predictive Value of Tests, Transcriptome, Adrenal Gland Neoplasms genetics, Interleukin-6 genetics, Receptors, Interleukin-6 drug effects, Receptors, Tumor Necrosis Factor, Type I genetics, Receptors, Tumor Necrosis Factor, Type II genetics, Tumor Necrosis Factor-alpha genetics
- Abstract
In the process of neoplasia, during which benign adrenal tumors are formed, stimulators of new blood vessel growth as well as growth of tumor cells are cytokines, especially tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). We analyzed the expression profile of genes coding: TNF-α, tumor necrosis factor receptor 1 (TNF-R1), TNF-R2, IL-6, interleukin 6 receptor (IL-6R) in sections of adrenocortical tumor tissue, rated on the Weiss point scale, in patients with clinically diagnosed Conn's and Cushing's syndrome, and the usefulness of determining the examined genes as markers differentiating individual clinical units. There was no correlation between the expression of the examined genes and clinical parameters such as age, BMI or blood pressure, both in the entire study group and in individual subgroups. Elevated expression of the genes coding TNF-α, TNF-R2 and IL-6R was observed, whereas genes encoding TNF-R1 and IL-6 showed relatively low expression. The highest statistically significant differences in the expression of the examined genes were observed between IL-6 and IL-6R. High positive correlation was found in the subgroup of patients with Conn's clinical syndrome, between genes encoding both types of receptors for TNF-α, IL-6 and TNF-R2, TNF-α and IL-6 receptor, and between TNF-R2 and IL6-R receptors, which may suggest the mutual influence of these cytokines and their receptors on their own expression.
- Published
- 2020
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24. Pneumocystis jirovecii Pneumonia in a HIV-Infected Patient with a CD4 Count Greater Than 400 Cells/ μ L and Atovaquone Prophylaxis.
- Author
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Sullivan A, Lanham T, Krol R, and Zachariah S
- Abstract
We describe a rare case of Pneumocystis jirovecii pneumonia (PCP) in a heterosexual man with a pertinent medical history of well-controlled human immunodeficiency virus (HIV) on highly active antiretroviral therapy (HAART) and PCP prophylaxis with atovaquone. The patient presented with recurrent shortness of breath, worsening malaise, and fever, following treatment for hypersensitivity pneumonitis one month prior, including a twenty-four-day course of 40 milligrams daily glucocorticoid with taper. However, transbronchial biopsies, lavage, and cytology from prior admission were inconclusive. The patient refused video-assisted thoracic surgery (VATS) at that time. Upon readmission, bronchoscopy with right VATS and lung biopsy were performed. Grocott's methenamine silver stain of right lung biopsy was positive for Pneumocystis jirovecii . This case is a rare example of PCP in a patient with a normal CD4 count (>487 cells/ μ L) and a low viral load (<20 copies/mL) despite PCP prophylactic antibiotics in the setting of recent iatrogenic immunosuppression., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Abigayle Sullivan et al.)
- Published
- 2020
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25. Editor's Choice - Nationwide Analysis of Patients Undergoing Iliac Artery Aneurysm Repair in the Netherlands.
- Author
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Jalalzadeh H, Indrakusuma R, Koelemay MJW, Balm R, Van den Akker LH, Van den Akker PJ, Akkersdijk GJ, Akkersdijk GP, Akkersdijk WL, van Andringa de Kempenaer MG, Arts CH, Avontuur JA, Baal JG, Bakker OJ, Balm R, Barendregt WB, Bender MH, Bendermacher BL, van den Berg M, Berger P, Beuk RJ, Blankensteijn JD, Bleker RJ, Bockel JH, Bodegom ME, Bogt KE, Boll AP, Booster MH, Borger van der Burg BL, de Borst GJ, Bos-van Rossum WT, Bosma J, Botman JM, Bouwman LH, Breek JC, Brehm V, Brinckman MJ, van den Broek TH, Brom HL, de Bruijn MT, de Bruin JL, Brummel P, van Brussel JP, Buijk SE, Buimer MG, Burger DH, Buscher HC, den Butter G, Cancrinus E, Castenmiller PH, Cazander G, Coveliers HM, Cuypers PH, Daemen JH, Dawson I, Derom AF, Dijkema AR, Diks J, Dinkelman MK, Dirven M, Dolmans DE, van Doorn RC, van Dortmont LM, van der Eb MM, Eefting D, van Eijck GJ, Elshof JW, Elsman BH, van der Elst A, van Engeland MI, van Eps RG, Faber MJ, de Fijter WM, Fioole B, Fritschy WM, Geelkerken RH, van Gent WB, Glade GJ, Govaert B, Groenendijk RP, de Groot HG, van den Haak RF, de Haan EF, Hajer GF, Hamming JF, van Hattum ES, Hazenberg CE, Hedeman Joosten PP, Helleman JN, van der Hem LG, Hendriks JM, van Herwaarden JA, Heyligers JM, Hinnen JW, Hissink RJ, Ho GH, den Hoed PT, Hoedt MT, van Hoek F, Hoencamp R, Hoffmann WH, Hoksbergen AW, Hollander EJ, Huisman LC, Hulsebos RG, Huntjens KM, Idu MM, Jacobs MJ, van der Jagt MF, Jansbeken JR, Janssen RJ, Jiang HH, de Jong SC, Jongkind V, Kapma MR, Keller BP, Khodadade Jahrome A, Kievit JK, Klemm PL, Klinkert P, Knippenberg B, Koedam NA, Koelemay MJ, Kolkert JL, Koning GG, Koning OH, Krasznai AG, Krol RM, Kropman RH, Kruse RR, van der Laan L, van der Laan MJ, van Laanen JH, Lardenoye JH, Lawson JA, Legemate DA, Leijdekkers VJ, Lemson MS, Lensvelt MM, Lijkwan MA, Lind RC, van der Linden FT, Liqui Lung PF, Loos MJ, Loubert MC, Mahmoud DE, Manshanden CG, Mattens EC, Meerwaldt R, Mees BM, Metz R, Minnee RC, de Mol van Otterloo JC, Moll FL, Montauban van Swijndregt YC, Morak MJ, van de Mortel RH, Mulder W, Nagesser SK, Naves CC, Nederhoed JH, Nevenzel-Putters AM, de Nie AJ, Nieuwenhuis DH, Nieuwenhuizen J, van Nieuwenhuizen RC, Nio D, Oomen AP, Oranen BI, Oskam J, Palamba HW, Peppelenbosch AG, van Petersen AS, Peterson TF, Petri BJ, Pierie ME, Ploeg AJ, Pol RA, Ponfoort ED, Poyck PP, Prent A, Ten Raa S, Raymakers JT, Reichart M, Reichmann BL, Reijnen MM, Rijbroek A, van Rijn MJ, de Roo RA, Rouwet EV, Rupert CG, Saleem BR, van Sambeek MR, Samyn MG, van 't Sant HP, van Schaik J, van Schaik PM, Scharn DM, Scheltinga MR, Schepers A, Schlejen PM, Schlosser FJ, Schol FP, Schouten O, Schreinemacher MH, Schreve MA, Schurink GW, Sikkink CJ, Siroen MP, Te Slaa A, Smeets HJ, Smeets L, de Smet AA, de Smit P, Smit PC, Smits TM, Snoeijs MG, Sondakh AO, van der Steenhoven TJ, van Sterkenburg SM, Stigter DA, Stigter H, Strating RP, Stultiëns GN, Sybrandy JE, Teijink JA, Telgenkamp BJ, Testroote MJ, The RM, Thijsse WJ, Tielliu IF, van Tongeren RB, Toorop RJ, Tordoir JH, Tournoij E, Truijers M, Türkcan K, Tutein Nolthenius RP, Ünlü Ç, Vafi AA, Vahl AC, Veen EJ, Veger HT, Veldman MG, Verhagen HJ, Verhoeven BA, Vermeulen CF, Vermeulen EG, Vierhout BP, Visser MJ, van der Vliet JA, Vlijmen-van Keulen CJ, Voesten HG, Voorhoeve R, Vos AW, de Vos B, Vos GA, Vriens BH, Vriens PW, de Vries AC, de Vries JP, de Vries M, van der Waal C, Waasdorp EJ, Wallis de Vries BM, van Walraven LA, van Wanroij JL, Warlé MC, van Weel V, van Well AM, Welten GM, Welten RJ, Wever JJ, Wiersema AM, Wikkeling OR, Willaert WI, Wille J, Willems MC, Willigendael EM, Wisselink W, Witte ME, Wittens CH, Wolf-de Jonge IC, Yazar O, Zeebregts CJ, and van Zeeland ML
- Subjects
- Aged, Aged, 80 and over, Endovascular Procedures methods, Endovascular Procedures mortality, Endovascular Procedures statistics & numerical data, Female, Guideline Adherence statistics & numerical data, Humans, Iliac Aneurysm epidemiology, Iliac Aneurysm mortality, Iliac Aneurysm pathology, Iliac Artery pathology, Iliac Artery surgery, Male, Netherlands epidemiology, Registries, Retrospective Studies, Sex Factors, Treatment Outcome, Iliac Aneurysm surgery
- Abstract
Objective: The new 2019 guideline of the European Society for Vascular Surgery (ESVS) recommends consideration for elective iliac artery aneurysm (eIAA) repair when the iliac diameter exceeds 3.5 cm, as opposed to 3.0 cm previously. The current study assessed diameters at time of eIAA repair and ruptured IAA (rIAA) repair and compared clinical outcomes after open surgical repair (OSR) and endovascular aneurysm repair (EVAR)., Methods: This retrospective observational study used the nationwide Dutch Surgical Aneurysm Audit (DSAA) registry that includes all patients who undergo aorto-iliac aneurysm repair in the Netherlands. All patients who underwent primary IAA repair between 1 January 2014 and 1 January 2018 were included. Diameters at time of eIAA and rIAA repair were compared in a descriptive fashion. The anatomical location of the IAA was not registered in the registry. Patient characteristics and outcomes of OSR and EVAR were compared with appropriate statistical tests., Results: The DSAA registry comprised 974 patients who underwent IAA repair. A total of 851 patients were included after exclusion of patients undergoing revision surgery and patients with missing essential variables. eIAA repair was carried out in 713 patients, rIAA repair in 102, and symptomatic IAA repair in 36. OSR was performed in 205, EVAR in 618, and hybrid repairs and conversions in 28. The median maximum IAA diameter at the time of eIAA and rIAA repair was 43 (IQR 38-50) mm and 68 (IQR 58-85) mm, respectively. Mortality was 1.3% (95% CI 0.7-2.4) after eIAA repair and 25.5% (95% CI 18.0-34.7) after rIAA repair. Mortality was not significantly different between the OSR and EVAR subgroups. Elective OSR was associated with significantly more complications than EVAR (intra-operative: 9.8% vs. 3.6%, post-operative: 34.0% vs. 13.8%, respectively)., Conclusion: In the Netherlands, most eIAA repairs are performed at diameters larger than recommended by the ESVS guideline. These findings appear to support the recent increase in the threshold diameter for eIAA repair., (Copyright © 2020 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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26. Low-Dose Versus High-Dose Radiation Therapy for the Palliation of Dysphagia From Esophageal Cancer: A Multicenter Retrospective Cohort Study.
- Author
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Vermeulen BD, Jeene PM, Sijben J, Krol R, Rütten H, Bogers JA, Braam PM, and Siersema PD
- Subjects
- Aged, Cohort Studies, Female, Humans, Male, Palliative Care methods, Prospective Studies, Retrospective Studies, Deglutition Disorders radiotherapy, Esophageal Neoplasms complications, Esophageal Neoplasms radiotherapy
- Abstract
Purpose: Clinical evidence regarding optimal radiation dose for palliation of dysphagia from esophageal cancer is generally lacking. In an effort to investigate optimal radiation dose, we assessed 2 different radiation schedules for palliation of dysphagia., Methods and Materials: We performed a multicenter, retrospective study comparing low-dose radiation therapy (LR: 5 x 4 Gy external beam radiation therapy [EBRT]) with high-dose radiation therapy (HR: 10 x 3 Gy EBRT and 12-Gy single-dose intraluminal brachytherapy) for palliation of dysphagia in patients with inoperable or metastasized esophageal cancer. Primary outcome was improvement of dysphagia at 6 weeks after start of radiation therapy. Additional outcomes were persistent and recurrent dysphagia during patients' remaining life, severe adverse events, and survival., Results: In total, 292 patients (LR, n = 117; HR, n = 175) were included in this study. After matching, 144 patients (72 in each group) were compared. Improvement of dysphagia at 6 weeks was achieved in 50% of patients after LR and in 66% after HR (P = .071). Persistent or recurrent dysphagia occurred in 64% of patients after LR and in 42% after HR (P = .012). No difference in the rate of severe adverse events was found (P = .889). Median survival was 88 days (95% confidence interval, 64-112) after LR and 177 days (95% confidence interval, 131-223) after HR (P < .001)., Conclusions: This study shows that both LR and HR were well tolerated and effective in short-term relief of dysphagia in patients with inoperable or metastasized esophageal cancer. HR was associated with better long-term relief of dysphagia compared with LR. Our findings suggest that HR could be considered for patients with a longer life expectancy, but prospective studies are required., (Copyright © 2019 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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27. Assessment of a W:BiVO 4 -CuBi 2 O 4 Tandem Photoelectrochemical Cell for Overall Solar Water Splitting.
- Author
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Song A, Bogdanoff P, Esau A, Ahmet IY, Levine I, Dittrich T, Unold T, van de Krol R, and Berglund SP
- Abstract
We assess a tandem photoelectrochemical cell consisting of a W:BiVO
4 photoanode top absorber and a CuBi2 O4 photocathode bottom absorber for overall solar water splitting. We show that the W:BiVO4 photoanode oxidizes water and produces oxygen at potentials ≥0.7 V vs RHE when CoPi is added as a cocatalyst. However, the CuBi2 O4 photocathode does not produce a detectable amount of hydrogen from water reduction even when Pt or RuOx is added as a cocatalyst because the photocurrent primarily goes toward photocorrosion of CuBi2 O4 rather than proton reduction. Protecting the CuBi2 O4 photocathode with a CdS/TiO2 heterojunction and adding RuOx as a cocatalyst prevents photocorrosion and allows for photoelectrochemical production of hydrogen at potentials ≤0.3 V vs RHE. A tandem photoelectrochemical cell composed of a W:BiVO4 /CoPi photoanode and a CuBi2 O4 /CdS/TiO2 /RuOx photocathode produces hydrogen which can be detected under illumination at an applied bias of ≥0.4 V. Since the valence band of BiVO4 and conduction band of CuBi2 O4 are adequately positioned to oxidize water and reduce protons, we hypothesize that the applied bias is required to overcome the relatively low photovoltages of the photoelectrodes, that is, the relatively low quasi-Fermi level splitting within BiVO4 and CuBi2 O4 . This work is the first experimental demonstration of hydrogen production from a BiVO4 -CuBi2 O4 -based tandem cell and it provides important insights into the significance of photovoltage in tandem devices for overall water splitting, especially for cells containing CuBi2 O4 photocathodes.- Published
- 2020
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28. Embedding laser generated nanocrystals in BiVO 4 photoanode for efficient photoelectrochemical water splitting.
- Author
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Jian J, Xu Y, Yang X, Liu W, Fu M, Yu H, Xu F, Feng F, Jia L, Friedrich D, van de Krol R, and Wang H
- Abstract
Addressing the intrinsic charge transport limitation of metal oxides has been of significance for pursuing viable PEC water splitting photoelectrodes. Growing a photoelectrode with conductive nanoobjects embedded in the matrix is promising for enhanced charge transport but remains a challenge technically. We herein show a strategy of embedding laser generated nanocrystals in BiVO
4 photoanode matrix, which achieves photocurrent densities of up to 5.15 mA cm-2 at 1.23 VRHE (from original 4.01 mA cm-2 ) for a single photoanode configuration, and 6.22 mA cm-2 at 1.23 VRHE for a dual configuration. The enhanced performance by such embedding is found universal owing to the typical features of laser synthesis and processing of colloids (LSPC) for producing ligand free nanocrystals in desired solvents. This study provides an alternative to address the slow bulk charge transport that bothers most metal oxides, and thus is significant for boosting their PEC water splitting performance.- Published
- 2019
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29. The electronic structure and the formation of polarons in Mo-doped BiVO 4 measured by angle-resolved photoemission spectroscopy.
- Author
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Mohamed M, May MM, Kanis M, Brützam M, Uecker R, van de Krol R, Janowitz C, and Mulazzi M
- Abstract
We experimentally investigated the electronic structure of Mo-doped BiVO
4 high-quality single-crystals with synchrotron radiation-excited angle-resolved photoelectron spectroscopy (ARPES). By photon-energy dependent ARPES, we measured the bulk-derived valence band dispersion along the direction normal to the (010) cleavage plane, while the dispersion along the in-plane directions is obtained by angle-dependent measurements at fixed photon energy. Our data show that the valence band has a width of about 4.75 eV and is composed of many peaks, the two most intense have energies in good agreement with the theoretically calculated ones. A non-dispersive feature is observed in the fundamental gap, which we attribute to quasiparticle excitations coupling electrons and phonons, i.e. polarons. The determination of the polaron peak binding energy and bulk band gap allows to fix the value of the theoretical mixing parameter necessary in hybrid Hartree-Fock calculations to reproduce the experimental data. The attribution of the in-gap peak to polarons is strengthened by our discussion in the context of experimental transport data and ab initio theory., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2019
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30. Femtosecond time-resolved two-photon photoemission studies of ultrafast carrier relaxation in Cu 2 O photoelectrodes.
- Author
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Borgwardt M, Omelchenko ST, Favaro M, Plate P, Höhn C, Abou-Ras D, Schwarzburg K, van de Krol R, Atwater HA, Lewis NS, Eichberger R, and Friedrich D
- Abstract
Cuprous oxide (Cu
2 O) is a promising material for solar-driven water splitting to produce hydrogen. However, the relatively small accessible photovoltage limits the development of efficient Cu2 O based photocathodes. Here, femtosecond time-resolved two-photon photoemission spectroscopy has been used to probe the electronic structure and dynamics of photoexcited charge carriers at the Cu2 O surface as well as the interface between Cu2 O and a platinum (Pt) adlayer. By referencing ultrafast energy-resolved surface sensitive spectroscopy to bulk data we identify the full bulk to surface transport dynamics for excited electrons rapidly localized within an intrinsic deep continuous defect band ranging from the whole crystal volume to the surface. No evidence of bulk electrons reaching the surface at the conduction band level is found resulting into a substantial loss of their energy through ultrafast trapping. Our results uncover main factors limiting the energy conversion processes in Cu2 O and provide guidance for future material development.- Published
- 2019
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31. Analysis of the interfacial characteristics of BiVO 4 /metal oxide heterostructures and its implication on their junction properties.
- Author
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Hermans Y, Murcia-López S, Klein A, van de Krol R, Andreu T, Morante JR, Toupance T, and Jaegermann W
- Abstract
The formation of heterostructures has proven to be a viable way to achieve high photoelectrochemical water splitting efficiencies with BiVO4 based photoanodes. Especially, cobalt and nickel based oxides are suitable low cost contact materials. However, the exact role of these contact materials is not yet completely understood because of the difficulty to individually quantify the effects of surface passivation, charge carrier separation and catalysis on the efficiency of a heterostructure. In this study, we used photoelectron spectroscopy in combination with in situ thin film deposition to obtain direct information on the interface structure between polycrystalline BiVO4 and NiO, CoOx and Sn-doped In2O3 (ITO). Strong upwards band bending was observed for the BiVO4/NiO and BiVO4/CoOx interfaces without observing chemical changes in BiVO4, while limited band bending and reduction of Bi and V was observed while forming the BiVO4/ITO interface. Thus, the tunability of the Fermi level position within BiVO4 seems to be limited to a certain range. The feasibility of high upwards band bending through junctions with high work function (WF) compounds demonstrate that nickel oxide and cobalt oxide are able to enhance the charge carrier separation in BiVO4. Similar studies could help to identify whether new photoelectrode materials and their heterostructures would be suitable for photoelectrochemical water splitting.
- Published
- 2019
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32. Allergic bronchopulmonary aspergillosis presumably unmasked by PD-1 inhibition.
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Donato AA and Krol R
- Subjects
- Antibodies, Fungal metabolism, Antibodies, Monoclonal, Humanized adverse effects, Aspergillosis, Allergic Bronchopulmonary chemically induced, Aspergillosis, Allergic Bronchopulmonary immunology, Eosinophils immunology, Humans, Male, Middle Aged, Tomography, X-Ray Computed, Adrenal Cortex Hormones therapeutic use, Aspergillosis, Allergic Bronchopulmonary diagnostic imaging, Aspergillosis, Allergic Bronchopulmonary drug therapy, Aspergillus fumigatus immunology, Voriconazole therapeutic use
- Abstract
Programmed cell death-1 (PD-1) inhibitors stimulate immune recognition of tumour cells in cancer patients, but have significant autoimmune side effects including pneumonitis. We report the case of a patient with asthma and mild eosinophilia who developed unusual pulmonary side effect of bronchiectasis, severe eosinophilia (absolute eosinophil count: 3200 c/mm
3 ) and elevated IgE levels (7050 IU/mL; normal: <164 IU/mL) 4 months into therapy with the PD-1 inhibitor pembrolizumab. Aspergillus fumigatus IgG was elevated at 15.60 U/mL (normal: <12.01 U/mL). He responded to therapy with corticosteroids and voriconazole and was able to resume pembrolizumab thereafter with good clinical response., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)- Published
- 2019
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33. Properdin binds independent of complement activation in an in vivo model of anti-glomerular basement membrane disease.
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O'Flynn J, Kotimaa J, Faber-Krol R, Koekkoek K, Klar-Mohamad N, Koudijs A, Schwaeble WJ, Stover C, Daha MR, and van Kooten C
- Subjects
- Animals, Anti-Glomerular Basement Membrane Disease pathology, Complement C3 genetics, Complement C3 metabolism, Disease Models, Animal, Female, Glomerular Basement Membrane cytology, Glomerular Basement Membrane immunology, Glomerular Basement Membrane pathology, Humans, Immunoglobulin G administration & dosage, Immunoglobulin G immunology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Neutrophils immunology, Properdin genetics, Properdin metabolism, Protein Binding immunology, Anti-Glomerular Basement Membrane Disease immunology, Complement Activation immunology, Complement C3 immunology, Properdin immunology
- Abstract
Properdin is the only known positive regulator of complement activation by stabilizing the alternative pathway convertase through C3 binding, thus prolonging its half-life. Recent in vitro studies suggest that properdin may act as a specific pattern recognition molecule. To better understand the role of properdin in vivo, we used an experimental model of acute anti-glomerular basement membrane disease with wild-type, C3- and properdin knockout mice. The model exhibited severe proteinuria, acute neutrophil infiltration and activation, classical and alternative pathway activation, and progressive glomerular deposition of properdin, C3 and C9. Although the acute renal injury was likely due to acute neutrophil activation, we found properdin deposition in C3-knockout mice that was not associated with IgG. Thus, properdin may deposit in injured tissues in vivo independent of its main ligand C3., (Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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34. Editorial: proton pump inhibitors (PPIs) and microscopic colitis.
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Krol R and van Oijen MGH
- Subjects
- Case-Control Studies, Denmark, Humans, Colitis, Microscopic, Proton Pump Inhibitors
- Published
- 2018
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35. Photocurrent Enhancement by Spontaneous Formation of a p-n Junction in Calcium-Doped Bismuth Vanadate Photoelectrodes.
- Author
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Abdi FF, Starr DE, Ahmet IY, and van de Krol R
- Abstract
The application of bismuth vanadate (BiVO
4 ) photoelectrodes for solar water splitting is hindered by the poor carrier transport. To overcome this, multiple donor-doping strategies (e.g. dual doping, gradient doping) have been explored. Here, we show for the first time the successful introduction of calcium (Ca) as an acceptor-type dopant into BiVO4 photoelectrodes. Interestingly, instead of generating cathodic photocurrents, the Ca-doped BiVO4 photoelectrodes show anodic photocurrents with an enhanced carrier separation efficiency. Hard X-ray photoelectron spectroscopy (HAXPES) shows that this enhancement is caused by out-diffusion of Ca during the deposition process, which spontaneously creates a p-n junction within the BiVO4 layer. Overall, a significant two-fold improvement of the AM1.5 photocurrent is obtained upon Ca-doping. This study highlights the importance of controlled doping beyond simply modifying carrier concentration and may enable new device architectures in photoelectrode materials., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2018
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36. Anal and rectal function after intensity-modulated prostate radiotherapy with endorectal balloon.
- Author
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Krol R, McColl GM, Hopman WPM, and Smeenk RJ
- Subjects
- Aged, Anal Canal physiopathology, Anal Canal radiation effects, Anus Diseases etiology, Humans, Longitudinal Studies, Male, Middle Aged, Pressure, Prospective Studies, Prostatic Neoplasms physiopathology, Quality of Life, Radiotherapy, Intensity-Modulated adverse effects, Radiotherapy, Intensity-Modulated methods, Rectal Diseases etiology, Rectum physiopathology, Rectum radiation effects, Anus Diseases physiopathology, Prostatic Neoplasms radiotherapy, Radiotherapy, Intensity-Modulated instrumentation, Rectal Diseases physiopathology
- Abstract
Background and Purpose: Late anorectal toxicity influences quality of life after external beam radiotherapy (EBRT) for prostate cancer. A daily inserted endorectal balloon (ERB) during EBRT aims to reduce anorectal toxicity. Our goal is to objectify anorectal function over time after prostate intensity-modulated radiotherapy (IMRT) with ERB., Material and Methods: Sixty men, irradiated with IMRT and an ERB, underwent barostat measurements and anorectal manometry prior to EBRT and 6 months, one year and 2 years after radiotherapy. Primary outcome measures were rectal distensibility and rectal sensibility in response to stepwise isobaric distensions and anal pressures., Results: Forty-eight men completed all measurements. EBRT reduced maximal rectal capacity 2 years after EBRT (250 ± 10 mL vs. 211 ± 10 mL; p < 0.001), area under the pressure-volume curve (2878 ± 270 mL mmHg vs. 2521 ± 305 mL mmHg; p = 0.043) and rectal compliance (NS). Sensory pressure thresholds for first sense and first urge (both p < 0.01) increased. Anal maximum pressure diminished after IMRT (p = 0.006)., Conclusions: Rectal capacity and sensory function are increasingly affected over time after radiotherapy. There is an indication that these reductions are affected less with IMRT + ERB compared to conventional radiation techniques., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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37. Light-Induced Surface Reactions at the Bismuth Vanadate/Potassium Phosphate Interface.
- Author
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Favaro M, Abdi FF, Lamers M, Crumlin EJ, Liu Z, van de Krol R, and Starr DE
- Abstract
Bismuth vanadate has recently drawn significant research attention as a light-absorbing photoanode due to its performance for photoelectrochemical water splitting. In this study, we use in situ ambient pressure X-ray photoelectron spectroscopy with "tender" X-rays (4.0 keV) to investigate a polycrystalline bismuth vanadate (BiVO
4 ) electrode in contact with an aqueous potassium phosphate (KPi) solution at open circuit potential under both dark and light conditions. This is facilitated by the creation of a 25 to 30 nm thick electrolyte layer using the "dip-and-pull" method. We observe that under illumination bismuth phosphate forms on the BiVO4 surface leading to an increase of the surface negative charge. The bismuth phosphate layer may act to passivate surface states observed in photoelectrochemical measurements. The repulsive interaction between the negatively charged surface under illumination and the phosphate ions in solution causes a shift in the distribution of ions in the thin aqueous electrolyte film, which is observed as an increase in their photoelectron signals. Interestingly, we find that such changes at the BiVO4 /KPi electrolyte interface are reversible upon returning to dark conditions. By measuring the oxygen 1s photoelectron peak intensities from the phosphate ions and liquid water as a function of time under dark and light conditions, we determine the time scales for the forward and reverse reactions. Our results provide direct evidence for light-induced chemical modification of the BiVO4 /KPi electrolyte interface.- Published
- 2018
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38. Are the patient-rated wrist evaluation (PRWE) and the disabilities of the arm, shoulder and hand (DASH) questionnaire used in distal radial fractures truly valid and reliable?
- Author
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Kleinlugtenbelt YV, Krol RG, Bhandari M, Goslings JC, Poolman RW, and Scholtes VAB
- Abstract
Objectives: The patient-rated wrist evaluation (PRWE) and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire are patient-reported outcome measures (PROMs) used for clinical and research purposes. Methodological high-quality clinimetric studies that determine the measurement properties of these PROMs when used in patients with a distal radial fracture are lacking. This study aimed to validate the PRWE and DASH in Dutch patients with a displaced distal radial fracture (DRF)., Methods: The intraclass correlation coefficient (ICC) was used for test-retest reliability, between PROMs completed twice with a two-week interval at six to eight months after DRF. Internal consistency was determined using Cronbach's α for the dimensions found in the factor analysis. The measurement error was expressed by the smallest detectable change (SDC). A semi-structured interview was conducted between eight and 12 weeks after DRF to assess the content validity., Results: A total of 119 patients (mean age 58 years (sd 15)), 74% female, completed PROMs at a mean time of six months (sd 1) post-fracture. One overall meaningful dimension was found for the PRWE and the DASH. Internal consistency was excellent for both PROMs (Cronbach's α 0.96 (PRWE) and 0.97 (DASH)). Test-retest reliability was good for the PRWE (ICC 0.87) and excellent for the DASH (ICC 0.91). The SDC was 20 for the PRWE and 14 for the DASH. No floor or ceiling effects were found. The content validity was good for both questionnaires., Conclusion: The PRWE and DASH are valid and reliable PROMs in assessing function and disability in Dutch patients with a displaced DRF. However, due to the high SDC, the PRWE and DASH are less useful for individual patients with a distal radial fracture in clinical practice. Cite this article : Y. V. Kleinlugtenbelt, R. G. Krol, M. Bhandari, J. C. Goslings, R. W. Poolman, V. A. B. Scholtes. Are the patient-rated wrist evaluation (PRWE) and the disabilities of the arm, shoulder and hand (DASH) questionnaire used in distal radial fractures truly valid and reliable? Bone Joint Res 2018;7:36-45. DOI: 10.1302/2046-3758.71.BJR-2017-0081.R1., Competing Interests: Conflicts of Interest Statement: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© 2018 Kleinlugtenbelt et al.)
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- 2018
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39. In situ XAS study of CoB i modified hematite photoanodes.
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Xi L, Schwanke C, Zhou D, Drevon D, van de Krol R, and Lange KM
- Abstract
Solar water splitting is a potentially scalable method to store solar energy in the form of renewable hydrogen gas. In this study, we demonstrate that the photoelectrochemical (PEC) performance of hematite photoanodes can be improved by modification with the oxygen evolution catalyst CoB
i . The current density at 1.23 V of the pristine hematite under one sun is 0.88 mA cm-2 and it increases to 1.12 mA cm-2 after CoBi modification (∼27% improvement). The presence of a CoBi cocatalayst layer is proposed to improve the oxygen evolution reaction (OER) kinetics and also to prevent electron-hole recombination at the surface via passivating surface defects as well as suppressing the tunneling of electrons from the hematite core, thus improving the photocurrents and resulting in a negative shift of photocurrent onset potentials. These effects of CoBi modification are supported by experimental data obtained by performing electrochemical impedance spectroscopy (EIS), PEC and incident photon-to-current efficiency (IPCE) measurements. To investigate the electronic structure of the CoBi cocatalyst deposited on hematite, XPS and in situ X-ray absorption spectroscopy (XAS) are employed. Co K-edge spectra at different potentials and light conditions are recorded. This makes the present work different from most of the previous studies. Using a quantitative analysis method, information on the mean oxidation state of Co in the CoBi film under applied potential and illumination is revealed. We also compare different methods for determining the oxidation state from the edge position and find that the integral method and half height methods are most suitable. In summary, the present work underlines the improvement of the semiconductor/cocatalyst interface of oxygen evolving photoanodes and strengthens the importance of in situ XAS spectroscopy when studying catalysts. This study is the first report so far combining the studies of the PEC performance of a CoBi modified hematite nanorod array photoanode and in situ XAS at the Co K-edge.- Published
- 2017
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40. Gradient Self-Doped CuBi 2 O 4 with Highly Improved Charge Separation Efficiency.
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Wang F, Septina W, Chemseddine A, Abdi FF, Friedrich D, Bogdanoff P, van de Krol R, Tilley SD, and Berglund SP
- Abstract
A new strategy of using forward gradient self-doping to improve the charge separation efficiency in metal oxide photoelectrodes is proposed. Gradient self-doped CuBi
2 O4 photocathodes are prepared with forward and reverse gradients in copper vacancies using a two-step, diffusion-assisted spray pyrolysis process. Decreasing the Cu/Bi ratio of the CuBi2 O4 photocathodes introduces Cu vacancies that increase the carrier (hole) concentration and lowers the Fermi level, as evidenced by a shift in the flat band toward more positive potentials. Thus, a gradient in Cu vacancies leads to an internal electric field within CuBi2 O4 , which can facilitate charge separation. Compared to homogeneous CuBi2 O4 photocathodes, CuBi2 O4 photocathodes with a forward gradient show highly improved charge separation efficiency and enhanced photoelectrochemical performance for reduction reactions, while CuBi2 O4 photocathodes with a reverse gradient show significantly reduced charge separation efficiency and photoelectrochemical performance. The CuBi2 O4 photocathodes with a forward gradient produce record AM 1.5 photocurrent densities for CuBi2 O4 up to -2.5 mA/cm2 at 0.6 V vs RHE with H2 O2 as an electron scavenger, and they show a charge separation efficiency of 34% for 550 nm light. The gradient self-doping accomplishes this without the introduction of external dopants, and therefore the tetragonal crystal structure and carrier mobility of CuBi2 O4 are maintained. Lastly, forward gradient self-doped CuBi2 O4 photocathodes are protected with a CdS/TiO2 heterojunction and coated with Pt as an electrocatalyst. These photocathodes demonstrate photocurrent densities on the order of -1.0 mA/cm2 at 0.0 V vs RHE and evolve hydrogen with a faradaic efficiency of ∼91%.- Published
- 2017
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41. Photocurrent of BiVO 4 is limited by surface recombination, not surface catalysis.
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Zachäus C, Abdi FF, Peter LM, and van de Krol R
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Bismuth vanadate is one of the most promising photoanode materials for photoelectrochemical water splitting. In order to achieve high photocurrents the surface of BiVO
4 always has to be modified with water oxidation catalysts, such as cobalt phosphate (CoPi), FeOOH, or NiFeOx . While this has generally been attributed to the poor intrinsic catalytic activity of BiVO4 , detailed insight into the fate of the photogenerated charge carriers at the surface is still lacking. We used intensity modulated photocurrent spectroscopy (IMPS) to investigate the surface carrier dynamics of bare and CoPi-modified spray-deposited BiVO4 films. Using a model developed by Peter et al. , it was possible to distinguish the reaction rate constants for surface recombination and charge transfer to the electrolyte. We found that modification with CoPi reduced the surface recombination of BiVO4 with a factor of 10-20, without significantly influencing the charge transfer kinetics. Control experiments with RuOx , one of the best known OER electrocatalysts, did not affect surface recombination and led to an actual decrease of the photocurrent. These results show that the main role of the CoPi is to passivate the surface of BiVO4 and that, contrary to earlier assumptions, the photocurrent of BiVO4 is limited by surface recombination instead of charge transfer. The importance of surface recombination is well recognized for conventional semiconductors in the field of photovoltaics; these findings show that it may also play a crucial role in oxide-based semiconductors for photoelectrochemical energy conversion.- Published
- 2017
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42. Hetero-type dual photoanodes for unbiased solar water splitting with extended light harvesting.
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Kim JH, Jang JW, Jo YH, Abdi FF, Lee YH, van de Krol R, and Lee JS
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Metal oxide semiconductors are promising photoelectrode materials for solar water splitting due to their robustness in aqueous solutions and low cost. Yet, their solar-to-hydrogen conversion efficiencies are still not high enough for practical applications. Here we present a strategy to enhance the efficiency of metal oxides, hetero-type dual photoelectrodes, in which two photoanodes of different bandgaps are connected in parallel for extended light harvesting. Thus, a photoelectrochemical device made of modified BiVO
4 and α-Fe2 O3 as dual photoanodes utilizes visible light up to 610 nm for water splitting, and shows stable photocurrents of 7.0±0.2 mA cm-2 at 1.23 VRHE under 1 sun irradiation. A tandem cell composed with the dual photoanodes-silicon solar cell demonstrates unbiased water splitting efficiency of 7.7%. These results and concept represent a significant step forward en route to the goal of >10% efficiency required for practical solar hydrogen production.- Published
- 2016
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43. Predictors of radiation-induced gastrointestinal morbidity: A prospective, longitudinal study following radiotherapy for carcinoma of the prostate.
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Yeoh EK, Krol R, Dhillon VS, Botten R, Di Matteo A, Butters J, Brock AR, Esterman A, Salisbury C, and Fenech M
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- Aged, Aged, 80 and over, Anal Canal radiation effects, Chronic Disease, Defecation radiation effects, Dose Fractionation, Radiation, Dose-Response Relationship, Radiation, Gastrointestinal Diseases diet therapy, Gastrointestinal Diseases etiology, Homocysteine blood, Humans, Longitudinal Studies, Male, Micronutrients blood, Middle Aged, Prospective Studies, Prostate, Radiation Dosage, Radiation Injuries diet therapy, Radiation Injuries etiology, Rectum radiation effects, South Australia epidemiology, Gastrointestinal Diseases epidemiology, Prostatic Neoplasms radiotherapy, Radiation Injuries epidemiology, Radiotherapy, Conformal adverse effects
- Abstract
Background Chronic gastrointestinal (GI) morbidity occurs in ≥50% of patients after external beam radiotherapy (EBRT) for carcinoma of prostate (CaP). This prospective, longitudinal study examines which baseline measurements of: 1) homocysteine and micronutrients in plasma; 2) chromosome damage/misrepair biomarkers; and 3) anal and rectal dose volume metrics predict GI morbidity after EBRT. Patients and methods In total, 106 patients with CaP had evaluations of GI symptoms (modified LENT-SOMA questionnaires) before EBRT and at one month, one, two and three years after its completion. Other variables measured before EBRT were: 1) plasma concentrations of homocysteine and micronutrients including caroteinoids and selenium; 2) chromosome damage/DNA misrepair (micronuclei/nucleoplasmic bridge) indices; and 3) mean anal and rectal wall doses and volumes of anal and rectal walls receiving ≥40 Gy and ≥60 Gy. Univariate and multivariate analyzes examined the relationships among: 1) plasma levels of homocysteine and micronutrients; 2) indices of chromosome damage/DNA misrepair; and 3) mean anal and rectal wall doses and volumes of anal and rectal walls receiving ≥40 Gy and ≥60 Gy and total GI symptom scores from one month to three years after EBRT. Results Increased frequency and urgency of defecation, rectal mucous discharge and bleeding after EBRT resulted in sustained rises in total GI symptom scores above baseline at three years. On univariate analysis, total GI symptom scores were significantly associated with: 1) plasma selenium and α tocopherol; 2) micronuclei indices of DNA damage; 3) mean anal and rectal wall doses; and 4) volumes of anal and rectal wall receiving ≥40 Gy and ≥60 Gy (p = 0.08-<0.001). On multivariate analysis, only volume of anal wall receiving ≥40 Gy was significant for increased GI symptoms after EBRT (p < 0.001). Conclusion The volume of anal wall receiving ≥40 Gy predicts chronic GI morbidity after EBRT for CaP.
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- 2016
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44. Microcontact-printing-assisted access of graphitic carbon nitride films with favorable textures toward photoelectrochemical application.
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Liu J, Wang H, Chen ZP, Moehwald H, Fiechter S, van de Krol R, Wen L, Jiang L, and Antonietti M
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An "ink" (cyanamide) infiltrated anodic aluminum oxide (AAO) stamp is found capable of printing carbon nitride films featuring regular microstructures of the stamp onto the substrates via in situ "chemical vapor deposition". A photocurrent density of 30.2 μA cm(-2 --) at 1.23 VRHE is achieved for a film on a conductive substrate, which is so far the highest value for pure carbon nitride based photoelectrochemical devices., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
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- 2015
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45. [Anorectal symptoms after prostate radiotherapy].
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Krol R, Smeenk RJ, van Lin EN, and Hopman WP
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- Fecal Incontinence etiology, Gastrointestinal Hemorrhage etiology, Humans, Male, Pressure, Quality of Life, Treatment Outcome, Anal Canal pathology, Prostatic Neoplasms radiotherapy, Radiotherapy adverse effects, Rectum pathology
- Abstract
Prostate cancer is the most common cancer in Dutch men and has a relatively good survival rate. Anorectal symptoms after irradiation of the prostate, including rectal blood loss and faecal incontinence, can have a serious impact on quality of life. On endoscopy, the Vienna Rectoscopy Score may reveal telangiectasia or other mucosal changes, but there may also be other causes of blood loss. Endoscopy or watchful waiting can be considered in patients with rectal bleeding. Sucralfate enemas, argon plasma coagulation and hyperbaric oxygen therapy are effective treatments. Increase in frequency of defaecation, faecal urgency or incontinence are related to decreased rectal compliance or to lowered anal resting pressure. Dietary measures can be considered in patients with faecal urgency or incontinence, but scientific evidence for the effectiveness of this is marginal. More accurate radiation techniques and the use of a spacer or endorectal balloon will probably contribute to maintaining rectal and anal function.
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- 2015
46. Efficient water-splitting device based on a bismuth vanadate photoanode and thin-film silicon solar cells.
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Han L, Abdi FF, van de Krol R, Liu R, Huang Z, Lewerenz HJ, Dam B, Zeman M, and Smets AH
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- Bismuth chemistry, Photochemical Processes, Solar Energy, Vanadates chemistry, Water chemistry
- Abstract
A hybrid photovoltaic/photoelectrochemical (PV/PEC) water-splitting device with a benchmark solar-to-hydrogen conversion efficiency of 5.2% under simulated air mass (AM) 1.5 illumination is reported. This cell consists of a gradient-doped tungsten-bismuth vanadate (W:BiVO4 ) photoanode and a thin-film silicon solar cell. The improvement with respect to an earlier cell that also used gradient-doped W:BiVO4 has been achieved by simultaneously introducing a textured substrate to enhance light trapping in the BiVO4 photoanode and further optimization of the W gradient doping profile in the photoanode. Various PV cells have been studied in combination with this BiVO4 photoanode, such as an amorphous silicon (a-Si:H) single junction, an a-Si:H/a-Si:H double junction, and an a-Si:H/nanocrystalline silicon (nc-Si:H) micromorph junction. The highest conversion efficiency, which is also the record efficiency for metal oxide based water-splitting devices, is reached for a tandem system consisting of the optimized W:BiVO4 photoanode and the micromorph (a-Si:H/nc-Si:H) cell. This record efficiency is attributed to the increased performance of the BiVO4 photoanode, which is the limiting factor in this hybrid PEC/PV device, as well as better spectral matching between BiVO4 and the nc-Si:H cell., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
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- 2014
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47. Acute amiodarone pulmonary toxicity following lung resection.
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Fadahunsi O and Krol R
- Abstract
Amiodarone is one of the most frequently prescribed antiarrhythmic agents. Despite its widespread use, it is associated with systemic side effects. Pulmonary toxicity, the most severe adverse effect of amiodarone, has usually been described in the context of chronic amiodarone use. We report a case of an 80-year-old male presenting acutely following right upper lung lobe resection for stage 1b adenocarcinoma. He developed atrial fibrillation on postoperative day four and received 12.5 g of amiodarone within a 12 day period. On presentation, he had new bilateral lung opacities and a 35% absolute decline in the predicted diffusion capacity for carbon monoxide. Pulmonary embolism was ruled out on chest computed tomography. Amiodarone was discontinued and prednisone was initiated. Despite initial improvement, he suffered from multiple hypoxemic episodes until his death in the fourth month. In a subset of patients undergoing thoracic surgery who are intubated and require high levels of oxygen, the risk of amiodarone lung toxicity increases and patients may present acutely.
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- 2014
48. Plasmonic enhancement of the optical absorption and catalytic efficiency of BiVO₄ photoanodes decorated with Ag@SiO₂ core-shell nanoparticles.
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Abdi FF, Dabirian A, Dam B, and van de Krol R
- Abstract
Recent progress in the development of bismuth vanadate (BiVO4) photoanodes has firmly established it as a promising material for solar water splitting applications. Performance limitations due to intrinsically poor catalytic activity and slow electron transport have been successfully addressed through the application of water oxidation co-catalysts and novel doping strategies. The next bottleneck to tackle is the modest optical absorption in BiVO4, particularly close to its absorption edge of 2.4 eV. Here, we explore the modification of the BiVO4 surface with Ag@SiO2 core-shell plasmonic nanoparticles. A photocurrent enhancement by a factor of ~2.5 is found under 1 sun illumination (AM1.5). We show that this enhancement consists of two contributions: optical absorption and catalysis. The optical absorption enhancement is induced by the excitation of localized surface plasmon resonances in the Ag nanoparticles, and agrees well with our full-field electromagnetic simulations. Far-field effects (scattering) are found to be dominant, with a smaller contribution from near-field plasmonic enhancement. In addition, a significant catalytic enhancement is observed, which is tentatively attributed to the electrocatalytic activity of the Ag@SiO2 nanoparticles.
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- 2014
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49. Simultaneous liver mucinous cystic and intraductal papillary mucinous neoplasms of the bile duct: a case report.
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Budzynska A, Hartleb M, Nowakowska-Dulawa E, Krol R, Remiszewski P, and Mazurkiewicz M
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- Bile Ducts, Extrahepatic pathology, Bile Ducts, Intrahepatic pathology, Carcinoma, Papillary complications, Cholangiopancreatography, Endoscopic Retrograde, Female, Humans, Liver Function Tests, Magnetic Resonance Imaging, Middle Aged, Neoplasms, Multiple Primary diagnosis, Tomography, X-Ray Computed, Treatment Outcome, Bile Duct Neoplasms complications, Bile Duct Neoplasms pathology, Carcinoma, Papillary pathology, Liver Neoplasms complications, Liver Neoplasms pathology, Neoplasms, Multiple Primary pathology
- Abstract
Cystic hepatic neoplasms are rare tumors, and are classified into two separate entities: mucinous cystic neoplasms (MCNs) and intraductal papillary mucinous neoplasms of the bile duct (IPMN-B). We report the case of a 56-year-old woman who presented with abdominal pain and jaundice due to the presence of a large hepatic multilocular cystic tumor associated with an intraductal tumor. Partial hepatectomy with resection of extrahepatic bile ducts demonstrated an intrahepatic MCN and an intraductal IPMN-B. This is the first report of the simultaneous occurrence of these two histologically distinct entities in the liver.
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- 2014
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50. Probing hydrogen spillover in Pd@MIL-101(Cr) with a focus on hydrogen chemisorption.
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Szilágyi PÁ, Callini E, Anastasopol A, Kwakernaak C, Sachdeva S, van de Krol R, Geerlings H, Borgschulte A, Züttel A, and Dam B
- Abstract
Palladium nanoparticles can split the dihydrogen bond and produce atomic hydrogen. When the metal nanoparticles are in intimate contact with a hydrogen-atom host, chemisorption of H-atoms by the host has been suggested to occur via the hydrogen spillover mechanism. Metal-organic frameworks were predicted to be able to act as effective chemisorption sites, and increased ambient-temperature hydrogen adsorption was reported on several occasions. The intimate contact was supposedly ensured by the use of a carbon bridge. In this work, we show that it is possible to introduce catalyst palladium particles into MOF's pores and simultaneously ensuring good contact, making the employment of the carbon bridge redundant. The addition of Pd nanoparticles indeed increases the ambient-temperature hydrogen uptake of the framework, but this is found to be solely due to palladium hydride formation. In addition, we show that the hydrogen atoms do not chemisorb on the host framework, which excludes the possibility of hydrogen spillover.
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- 2014
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