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排序方式: 共有259条查询结果,搜索用时 62 毫秒
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Crozet Marielle Roudil Danièle Rigaux Corinne Bertorello Caroline Picart Sébastien Maillard Christophe 《Journal of Radioanalytical and Nuclear Chemistry》2019,321(1):367-367
Journal of Radioanalytical and Nuclear Chemistry - In the original publication of the article, the values of u(s), u(r) and ITV for HKED were published incorrectly in Table 6. 相似文献
33.
Yong Gao Dani Zhang Dr. Jingjing Li Prof. Hao Gong Dr. Cheng Jiang Dr. Hairong Xue Prof. Xianli Huang Prof. Tao Wang Prof. Jianping He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(71):e202202410
Electrocatalysis is the most promising strategy to generate clean energy H2, and the development of catalysts with excellent hydrogen evolution reaction (HER) performance at high current density that can resist strong alkaline and acidic electrolyte environment is of great significance for practical industrial application. Therefore, a P doped MoS2@Ni3S2 nanorods array (named P-NiMoS) was successfully synthesized through successive sulfuration and phosphorization. P-NiMoS presents a core/shell structure with a heterojunction between MoS2 (shell) and Ni3S2 (core). Furthermore, the doping of P modulates the electronic structure of the P-NiMoS; the electrons transfer from the t2g orbital of Ni element to the eg empty orbital of Mo element through the Ni−S−Mo bond at the Ni3S2 and MoS2 heterojunction, facilitating the hydrogen evolution reaction. As a result, P-NiMoS exhibits excellent HER activity; the overpotential is 290 mV at high current density of 250 mA cm−2 in alkaline electrolyte, which is close to Pt/C (282 mV@250 mA cm−2), and P-NiMoS can stably evolve hydrogen for 48 h. 相似文献
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Redox‐Active‐Ligand‐Mediated Formation of an Acyclic Trinuclear Ruthenium Complex with Bridging Nitrido Ligands
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Dr. Bidraha Bagh Daniël L. J. Broere Dr. Maxime A. Siegler Dr. Ir. Jarl Ivar van der Vlugt 《Angewandte Chemie (International ed. in English)》2016,55(29):8381-8385
Coordination of a redox‐active pyridine aminophenol ligand to RuII followed by aerobic oxidation generates two diamagnetic RuIII species [ 1 a (cis) and 1 b (trans)] with ligand‐centered radicals. The reaction of 1 a / 1 b with excess NaN3 under inert atmosphere resulted in the formation of a rare bis(nitrido)‐bridged trinuclear ruthenium complex with two nonlinear asymmetrical Ru‐N‐Ru fragments. The spontaneous reduction of the ligand centered radical in the parent 1 a / 1 b supports the oxidation of a nitride (N3?) to half an equivalent of N2. The trinuclear omplex is reactive toward TEMPO‐H, tin hydrides, thiols, and dihydrogen. 相似文献
36.
João Medeiros‐Silva Deni Mance Mark Daniëls Shehrazade Jekhmane Dr. Klaartje Houben Prof. Marc Baldus Dr. Markus Weingarth 《Angewandte Chemie (International ed. in English)》2016,55(43):13606-13610
1H detection can significantly improve solid‐state NMR spectral sensitivity and thereby allows studying more complex proteins. However, the common prerequisite for 1H detection is the introduction of exchangeable protons in otherwise deuterated proteins, which has thus far significantly hampered studies of partly water‐inaccessible proteins, such as membrane proteins. Herein, we present an approach that enables high‐resolution 1H‐detected solid‐state NMR (ssNMR) studies of water‐inaccessible proteins, and that even works in highly complex environments such as cellular surfaces. In particular, the method was applied to study the K+ channel KcsA in liposomes and in situ in native bacterial cell membranes. We used our data for a dynamic analysis, and we show that the selectivity filter, which is responsible for ion conduction and highly conserved in K+ channels, undergoes pronounced molecular motion. We expect this approach to open new avenues for biomolecular ssNMR. 相似文献
37.
Insight into 3D micro‐CT data: exploring segmentation algorithms through performance metrics
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Talita Perciano Daniela Ushizima Harinarayan Krishnan Dilworth Parkinson Natalie Larson Daniël M. Pelt Wes Bethel Frank Zok James Sethian 《Journal of synchrotron radiation》2017,24(5):1065-1077
Three‐dimensional (3D) micro‐tomography (µ‐CT) has proven to be an important imaging modality in industry and scientific domains. Understanding the properties of material structure and behavior has produced many scientific advances. An important component of the 3D µ‐CT pipeline is image partitioning (or image segmentation), a step that is used to separate various phases or components in an image. Image partitioning schemes require specific rules for different scientific fields, but a common strategy consists of devising metrics to quantify performance and accuracy. The present article proposes a set of protocols to systematically analyze and compare the results of unsupervised classification methods used for segmentation of synchrotron‐based data. The proposed dataflow for Materials Segmentation and Metrics (MSM) provides 3D micro‐tomography image segmentation algorithms, such as statistical region merging (SRM), k‐means algorithm and parallel Markov random field (PMRF), while offering different metrics to evaluate segmentation quality, confidence and conformity with standards. Both experimental and synthetic data are assessed, illustrating quantitative results through the MSM dashboard, which can return sample information such as media porosity and permeability. The main contributions of this work are: (i) to deliver tools to improve material design and quality control; (ii) to provide datasets for benchmarking and reproducibility; (iii) to yield good practices in the absence of standards or ground‐truth for ceramic composite analysis. 相似文献
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Thirunavukkarasu Annamalai Neil Dani Bokun Cheng Yuk-Ching Tse-Dinh 《BMC biochemistry》2009,10(1):18-8
Background
Mycobacterium tuberculosis DNA topoisomerase I is an attractive target for discovery of novel TB drugs that act by enhancing the accumulation of the topoisomerase-DNA cleavage product. It shares a common transesterification domain with other type IA DNA topoisomerases. There is, however, no homology between the C-terminal DNA binding domains of Escherichia coli and M. tuberculosis DNA topoisomerase I proteins. 相似文献40.
Koole R Liljeroth P de Mello Donega C Vanmaekelbergh D Meijerink A 《Journal of the American Chemical Society》2006,128(32):10436-10441
Stable dispersions of molecularlike aggregates of CdTe quantum dots are prepared by chemical cross-linking. Cryo-TEM images confirm the presence of cross-linked quantum dots and show that the size of the small aggregates can be controlled by the amount of cross-linker added. Optical measurements reveal two types of interdot interactions within these quantum-dot molecules: exciton energy transfer and electronic coupling. Quantitative information on the energy transfer rates in quantum-dot molecules is obtained by photoluminescence lifetime measurements. The degree of electronic coupling is dependent on the size of the quantum dots, which is supported by quantum mechanical calculations. 相似文献