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排序方式: 共有932条查询结果,搜索用时 14 毫秒
1.
Dr. Haixiang Han Jesse C. Carozza Audra P. Colliton Yuxuan Zhang Dr. Zheng Wei Dr. Alexander S. Filatov Prof. Dr. Yu-Sheng Chen Melisa Alkan Prof. Dr. Andrey Yu. Rogachev Prof. Dr. Evgeny V. Dikarev 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9711-9717
A known trinuclear structure was used to design the heterobimetallic mixed-valent, mixed-ligand molecule [CoII(hfac)3−Na−CoIII(acac)3] ( 1 ). This was used as a template structure to develop heterotrimetallic molecules [CoII(hfac)3−Na−FeIII(acac)3] ( 2 ) and [NiII(hfac)3−Na−CoIII(acac)3] ( 3 ) via isovalent site-specific substitution at either of the cobalt positions. Diffraction methods, synchrotron resonant diffraction, and multiple-wavelength anomalous diffraction were applied beyond simple structural investigation to provide an unambiguous assignment of the positions and oxidation states for the periodic table neighbors in the heterometallic assemblies. Molecules of 2 and 3 are true heterotrimetallic rather than a statistical mixture of two heterobimetallic counterparts. Trinuclear platform 1 exhibits flexibility in accommodating a variety of di- and trivalent metals, which can be further utilized in the design of molecular precursors for the NaMM′O4 functional oxide materials. 相似文献
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DNA release electrochemically stimulated by applying ?10 mV on the modified electrode was studied. The release process was based on the local (interfacial) pH change produced upon H2O2 reduction electrocatalyzed by the immobilized microperoxidase‐11. SiO2 nanoparticles attached to the electrode surface and functionalized with trigonelline and boronic acid species changed their electrical charge from positive to negative upon the interfacial pH change, thus allowing electrostatic adsorption of negatively charged DNA on the positive interface and then its repulsion/release from the negative interface. The loaded/released DNA molecules were labeled with a fluorescent dye to allow easy detection of the released DNA molecules. The important feature of the developed system is the controlled DNA release upon applying very small electrical potential on the modified electrode. 相似文献
4.
Chemistry of Heterocyclic Compounds - This microreview presents the current state of research on functionalization of α-mangostin, a natural hydroxyxanthone. Examples of transformations are... 相似文献
5.
Kattakgoundar Govindaraj Sudha Saheb Ali Gopalu Karunakaran Mariyappan Kowsalya Evgeny Kolesnikov Mohan Prasanna Rajeshkumar 《应用有机金属化学》2020,34(4):e5511
The tunable ZnO nanorods (NRs) are produced due to the phytochemicals present in Cycas pschannae leaves which act as reducing and stabilizing agents. The confirmations of the ZnO NRs were validated using different characterization techniques: X-ray diffraction, Fourier transform infrared spectroscopy, Brunauer, Emmett and Teller (BET), scanning electron microscopy–Energy Dispersive X-Ray Analysis (EDX), UV–visible spectroscopy, Raman spectroscopy, and transmission electron microscopy. The ZnO NRs show unique surface area and low particle size. Photocatalytic activity was measured and found to be 50.75% at low concentrations and 78.33% at high concentrations. The antioxidant activity of the ZnO NRs also showed promising results for their use in free radical scavenging. In vitro toxicity studies using zebrafish embryos was performed to evaluate the toxic nature of it and the obtained result confirmed its non-toxic nature. In addition, ZnO anticancer potential was verified using the A549 lung cancer cell line. Cytotoxic assessments of ZnO NRs were performed via 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), and neutral red uptake assays to examine the cell death cycle on the A549 lung cancer cell. Dose-dependent apoptosis and necrosis were confirmed by Lactate dehydrogenase (LDH) assay. It was also confirmed that ZnO NRs induce Reactive oxygen species (ROS) and apoptosis inside cancer (A549) cells via different intrinsic gene expression. Thus, based on this research it is evident that an effective ecofriendly, nontoxic potential anticancer drug can be synthesized using C. pschannae leaf extract. 相似文献
6.
Karcher Wolfgang Roth Stefan Spodarev Evgeny Walk Corinna 《Statistical Inference for Stochastic Processes》2019,22(2):263-306
Statistical Inference for Stochastic Processes - Given a low frequency sample of an infinitely divisible moving average random field $$\{\int _{\mathbb {R}^d} f(x-t)\varLambda (dx); \ t \in \mathbb... 相似文献
7.
Evgeny M. Apfelbaum 《等离子体物理论文集》2019,59(4-5)
The thermophysical properties of low‐temperature Pb plasma are calculated at temperatures 10–100 kK and densities below 0.2 of the solid‐state value. The thermodynamic values (pressure and internal energy) and transport coefficients (electrical conductivity, thermal conductivity, and thermal power) are considered. The plasma composition and thermodynamic parameters are obtained within the chemical approach, namely by means of the solution of the corresponding system of the coupled mass action law equations. Atom ionization up to +4 is taken into consideration. The electronic transport coefficients are calculated within the relaxation time approximation. The results obtained by means of the present model are compared with the available data of other models and experiments. 相似文献
8.
Ronald C. Crouch Jeffrey G. Raab Marius Pelmuş Evgeny Tischenko Michael Frey Alexei V. Buevich Mikhail Reibarkh R. Thomas Williamson Gary E. Martin 《Magnetic resonance in chemistry : MRC》2022,60(2):210-220
Modification of the recently reported 19F-detected 1,1-ADEQUATE experiment that incorporates dual-optimization to selectively invert a wide range of 1JCC correlations in a 1,n-ADEQUATE experiment is reported. Parameters for the dual-optimization segment of the pulse sequence were modified to accommodate the increased size of 1JCC homonuclear coupling constants of poly- and perfluorinated molecules relative to protonated molecules to allow broadband inversion of the 1JCC correlations. The observation and utility of isotope shifts are reported for the first time for 1,1- and 1,n-ADEQUATE correlations. 相似文献
9.
Robbert van Putten Evgeny A. Uslamin Marcel Garbe Chong Liu Dr. Angela Gonzalez-de-Castro Dr. Martin Lutz Dr. Kathrin Junge Prof. Dr. Emiel J. M. Hensen Prof. Dr. Matthias Beller Dr. Laurent Lefort Prof. Dr. Evgeny A. Pidko 《Angewandte Chemie (International ed. in English)》2017,56(26):7531-7534
Catalytic hydrogenation of carboxylic acid esters is essential for the green production of pharmaceuticals, fragrances, and fine chemicals. Herein, we report the efficient hydrogenation of esters with manganese catalysts based on simple bidentate aminophosphine ligands. Monoligated Mn PN complexes are particularly active for the conversion of esters into the corresponding alcohols at Mn concentrations as low as 0.2 mol % in the presence of sub-stoichiometric amounts of KOtBu base. 相似文献
10.
We consider inverse potential scattering problems where the source of the incident waves is located on a smooth closed surface outside of the inhomogeneity of the media. The scattered waves are measured on the same surface at a fixed value of the energy. We show that these data determine the bounded potential uniquely. 相似文献