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1.
First principles computational studies of spontaneous reduction reaction of Eu(III) in eutectic LiCl‐KCl molten salt 下载免费PDF全文
Using first principles calculations, we study fundamental mechanism of spontaneous reduction reaction of Eu3+ to Eu2+ in eutectic LiCl‐KCl molten salt. We decouple the reaction Gibbs free energy into enthalpy and entropy contributions by using rigorous thermodynamic formalism. Key structural features of the solvation shell are characterized by the radial distribution function and the coordination number. Compared with Eu2+, the Eu3+ ion has a more rigid framework of the solvation shells, corroborating its stronger electrostatic interaction with neighboring ligands of Cl? ions and a more favorable state on the aspect of enthalpy. Computations on vibrational frequency, however, pose significant contribution of vibrational entropy to the reaction Gibbs free energy for the reduction. Vibration frequency of Eu2+ is smaller than that of Eu3+, driving a more positive change of the entropy in the reduction reaction. Furthermore, an Eu2+ diffuses more quickly than an Eu3+ in the LiCl‐KCl molten salt with switching mechanism of ligand Cl? ions in the solvation shell. Our results propose that the spontaneity of the reduction reaction is driven by the entropic contribution by overcoming the penalty of the reaction enthalpy. 相似文献
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Jongmin Lee Hongji Yoon Kyoung Soon Choi Seungkyu Kim Sehun Seo Jaesun Song Byeong‐Uk Choi Jiseung Ryu Sangwoo Ryu Jihun Oh Cheolho Jeon Sanghan Lee 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(39)
To develop strategies for efficient photo‐electrochemical water‐splitting, it is important to understand the fundamental properties of oxide photoelectrodes by synthesizing and investigating their single‐crystal thin films. However, it is challenging to synthesize high‐quality single‐crystal thin films from copper‐based oxide photoelectrodes due to the occurrence of significant defects such as copper or oxygen vacancies and grains. Here, the CuBi2O4 (CBO) single‐crystal thin film photocathode is achieved using a NiO template layer grown on single‐crystal SrTiO3 (STO) (001) substrate via pulsed laser deposition. The NiO template layer plays a role as a buffer layer of large lattice mismatch between CBO and STO (001) substrate through domain‐matching epitaxy, and forms a type‐II band alignment with CBO, which prohibits the transfer of photogenerated electrons toward bottom electrode. The photocurrent densities of the CBO single‐crystal thin film photocathode demonstrate ?0.4 and ?0.7 mA cm?2 at even 0 VRHE with no severe dark current under illumination in a 0.1 m potassium phosphate buffer solution without and with H2O2 as an electron scavenger, respectively. The successful synthesis of high‐quality CBO single‐crystal thin film would be a cornerstone for the in‐depth understanding of the fundamental properties of CBO toward efficient photo‐electrochemical water‐splitting. 相似文献
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Kim Ho Jin Lee Mi Jin Park Hye Jin Kim Hye Jin Cho Soon Kil Jeong Min Hee 《Food science and biotechnology》2018,27(3):877-882
Food Science and Biotechnology - A new analytical method was developed for the simultaneous determination of seven food additives (Ponceau 4R, Allura Red AC, Amaranth, 4-hydroxymethyl benzoic acid,... 相似文献
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Jongwoo Kim Eun Hee Park Young Soon Park Kyung Hee Chun Lynn L. Wiles 《Information Systems Journal》2022,32(1):164-191
Regulations, such as the Health Insurance Portability and Accountability Act (HIPAA), establish standards to protect patients' medical records from security breaches. Insiders' prosocial misbehaviour within healthcare organisations can cause significant damage to relevant stakeholders. Such behaviour without malicious intention needs to be better understood and carefully managed from the perspective of prosocial behaviour. For this study, a research model was developed that includes the factors influencing student nurses' intention to disclose patient health information. The model was empirically tested with nursing students in South Korea with a scenario-based experiment. We find that both altruistic (impact on others) and egoistic (impact on the self) motivations are significantly important in raising situational empathy. On the other hand, an egoistic motivation (impact on the self) significantly affects people's perception of their responsibility, which mediates the relationship between situational empathy and prosocial intention to disclose. The implications of our findings are discussed. 相似文献
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Soon Ki Kim Sung Hyun Hwang Jun-Tae Nam Jong-Sung Park 《Ceramics International》2021,47(15):21083-21089
Generally, the NiO composite anode becomes porous after reduction. To infiltrate additional catalysts such as Pd into the NiO-composite anode before reducing NiO to Ni, a porous NiO composite anode for protonic ceramic fuel cells (PCFCs) was fabricated in this study. The porous NiO composite was fabricated by adding graphite as a pore former along with CuO as a sintering agent. The addition of graphite increased the porosity of the NiO composite anode but resulted in poor sinterability, which was addressed by adding CuO as a sintering agent to the NiO composite anode. The Pd catalyst was added to the NiO-composite anode before reducing NiO to Ni. The composite anode for PCFC with three components, namely Ni, protonic ceramics, and a Pd catalyst, was obtained by reducing NiO to Ni during the measurement. The addition of the Pd catalyst improved the anode performance in methane fuel and hydrogen fuel by enhancing the catalytic activity for the electrochemical reaction on the surface. 相似文献
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The Journal of Supercomputing - This study proposes an efficient exact k-flexible aggregate nearest neighbor (k-FANN) search algorithm in road networks using the M-tree. The state-of-the-art... 相似文献