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排序方式: 共有693条查询结果,搜索用时 15 毫秒
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Dey Chaudhuri S. Banerjee D. Bhattacharjee T. Wasim Raja Sk Acharya R. Pujari P. K. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):829-835
Journal of Radioanalytical and Nuclear Chemistry - Performance of 1″?×?1″ LaBr3 (5% Ce) scintillator coupled to Hamamatsu R2083 PM Tube has been investigated for the... 相似文献
3.
Li Shiuan Ng Dr. Tharishinny Raja Mogan Jinn-Kye Lee Dr. Haitao Li Dr. Chi-Lik Ken Lee Prof. Hiang Kwee Lee 《Angewandte Chemie (International ed. in English)》2023,62(47):e202313695
The production of green hydrogen through photocatalytic water splitting is crucial for a sustainable hydrogen economy and chemical manufacturing. However, current approaches suffer from slow hydrogen production (<70 μmol ⋅ gcat−1 ⋅ h−1) due to the sluggish four-electrons oxygen evolution reaction (OER) and limited catalyst activity. Herein, we achieve efficient photocatalytic water splitting by exploiting a multifunctional interface between a nano-photocatalyst and metal–organic framework (MOF) layer. The functional interface plays two critical roles: (1) enriching electron density directly on photocatalyst surface to promote catalytic activity, and (2) delocalizing photogenerated holes into MOF to enhance OER. Our photocatalytic ensemble boosts hydrogen evolution by ≈100-fold over pristine photocatalyst and concurrently produces oxygen at ideal stoichiometric ratio, even without using sacrificial agents. Notably, this unique design attains superior hydrogen production (519 μmol ⋅ gcat−1 ⋅ h−1) and apparent quantum efficiency up to 13-fold and 8-fold better than emerging photocatalytic designs utilizing hole scavengers. Comprehensive investigations underscore the vital role of the interfacial design in generating high-energy photoelectrons on surface-degenerate photocatalyst to thermodynamically drive hydrogen evolution, while leveraging the nanoporous MOF scaffold as an effective photohole sink to enhance OER. Our interfacial approach creates vast opportunities for designing next-generation, multifunctional photocatalytic ensembles using reticular chemistry with diverse energy and environmental applications. 相似文献
4.
Dr. Nimisha Jain Angelina Mary Tanu Singh Srushti Gadiyaram Dr. Jyoti Joshi Dr. D. Amilan Jose Dr. Abbas Raja Naziruddin 《欧洲无机化学杂志》2023,26(26):e202300210
We report heteroleptic ruthenium complexes of terpyridine (tpy) ligands with directly linked carboxylic acid anchors. These complexes feature methyl or methoxy-substituted 4′−Phtpy as donor ligands. We prepared these heteroleptic complexes from the ruthenium (II) precursor via a milder route to preclude the homoleptic complex formation. The donor−acceptor arrangement of tpy ligands in these ruthenium complexes renders visible light absorption giving metal and ligand-to-ligand charge transfer excitations at c.a. 490 nm. We evaluate the effect of the tpy donor substituents on the light-harvesting ability in Dye-Sensitized Solar Cells (DSSCs) and compare their photosensitizing ability with heteroleptic complexes bearing phenyl spacer at the acceptor end. Further, scrutinizing their photovoltaic performance, we studied their electron transfer kinetics in DSSCs using electrochemical impedance spectroscopy. This paper presents the structure-photosensitization relationship of these heteroleptic ruthenium complexes through a combined experimental and computational approach. 相似文献
5.
Ortho‐Quinone Methides as Reactive Intermediates in Asymmetric Brønsted Acid Catalyzed Cycloadditions with Unactivated Alkenes by Exclusive Activation of the Electrophile 下载免费PDF全文
MSc. Chien‐Chi Hsiao Dr. Sadiya Raja MSc. Hsuan‐Hung Liao Prof. Dr. Magnus Rueping 《Angewandte Chemie (International ed. in English)》2015,54(19):5762-5765
An efficient method for the highly enantioselective synthesis of chiral chromanes bearing multiple stereogenic centers was developed. A chiral BINOL‐based N‐triflylphosphoramide proved to be an effective catalyst for the in situ generation of ortho‐quinone methides (o‐QMs) and their subsequent cycloaddition reaction with unactivated alkenes provided chromanes with excellent diastereo‐ and enantioselectivity. 相似文献
6.
Thermal and salt dual stimuli-responsive filter-paper-based membranes were prepared by UV-induced grafting of NIPAM-based polymers on paper surface. The grafting ratio could be controlled by monomer concentration during grafting polymerization. The results from pressure drop measurement of the mobile phase flowed cross the membrane demonstrate that an appropriate grafting ratio would be 8%-10%. Protein adsorption on the membrane through hydrophobic interaction could be promoted by increasing temperature and lyotropic salt concentration. The effect of grafted polymer structure on protein binding performance was studied. Filter paper grafted with NIPAM-based branched copolymer consisting of hydrophobic monomer moieties shows ten times higher protein binding capacity than that of the original filter paper. The separation of plasma proteins using the dual stimuli-responsive membrane was examined to demonstrate feasible application for hydrophobic interaction chromatographic separation of proteins. 相似文献
7.
The Lie group of point transformations, which leave the equations for a simplified model of one dimensional ideal gas in magnetogasdynamics invariant, are used to obtain some exact solutions for the governing system of hyperbolic partial differential equations (PDEs). Similarity variables which reduces the governing system of PDEs into system of ordinary differential equations (ODEs) are determined through the transformations. The resulting ODEs are solved analytically to obtain some exact solutions that exhibits space-time dependence. Further, we study the propagation of weak discontinuity through a state characterized by one of the solutions. 相似文献
8.
Remarkable Effect of Chalcogen Substitution on an Enzyme Mimetic for Deiodination of Thyroid Hormones 下载免费PDF全文
Karuppusamy Raja Prof. Dr. Govindasamy Mugesh 《Angewandte Chemie (International ed. in English)》2015,54(26):7674-7678
Iodothyronine deiodinases are selenoenzymes which regulate the thyroid hormone homeostasis by catalyzing the regioselective deiodination of thyroxine (T4). Synthetic deiodinase mimetics are important not only to understand the mechanism of enzyme catalysis, but also to develop therapeutic agents as abnormal thyroid hormone levels have implications in different diseases, such as hypoxia, myocardial infarction, critical illness, neuronal ischemia, tissue injury, and cancer. Described herein is that the replacement of sulfur/selenium atoms in a series of deiodinase mimetics by tellurium remarkably alters the reactivity as well as regioselectivity toward T4. The tellurium compounds reported in this paper represent the first examples of deiodinase mimetics which mediate sequential deiodination of T4 to produce all the hormone derivatives including T0 under physiologically relevant conditions. 相似文献
9.
Jahangeer Patujo Amin Badshah Raja Azadar Hussain Muhammad Nawaz Tahir Shaista Tahir Muhammad Khawar Rauf 《中国化学会会志》2015,62(11):1020-1027
In the present work new nitro substituted thioureas, and their copper complexes have been synthesized and characterized by FTIR and multinuclear NMR techniques. Some of the compounds namely 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐1), 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐2) and 1‐benzoyl‐3‐(2‐methoxy‐4‐nitrophenyl) thiourea (A‐2) have also been characterized by single crystal XRD. All the synthesized compounds have been screened for DNA binding potencies (using cyclic voltametry, UV‐vis spectroscopy) and free radical scavanging activities. 相似文献
10.
Tamoghna Bhattacharyya Arumoy Chatterjee Budhaditya Chatterjee Sufi O. Raja Anjan Kr. Dasgupta 《Electrophoresis》2015,36(24):3009-3013
We report both the experimental and theoretical insights of differential electro‐diffusion behavior of carbon nanomaterials (e.g. single wall, multiwall carbon nanotubes, and graphene). We thus discriminate one from the other in a soft gel system. The differential mobility of such material depends on their intrinsic properties, both extend and rate of migration bearing the discriminatory signature. The mobility analysis is made by a real time monitoring of the respective bands. 相似文献