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排序方式: 共有97条查询结果,搜索用时 93 毫秒
91.
92.
Johannes Tophøj Rasmussen Georges-Henri Cottet Jens Honoré Walther 《Journal of computational physics》2011,230(17):6742-6755
We present a novel multiresolution Vortex-In-Cell algorithm using patches of varying resolution. The Poisson equation relating the fluid vorticity and velocity is solved using Fast Fourier Transforms subject to free space boundary conditions. Solid boundaries are implemented using the semi-implicit formulation of Brinkman penalization and we show that the penalization can be carried out as a simple interpolation. We validate the implementation against the analytic solution to the Perlman test case and by free-space simulations of the onset flow around fixed and rotating circular cylinders and bluff body flows around bridge sections. 相似文献
93.
Synthesis and Structural Characterization of a Binuclear Mixed‐Ligand (Salicylate and N,N‐diethylnicotinamide) Nickel(II) Complex,Its Magnetic Properties. [Ni2(µ‐Sal)4(Dena)2]H2O 下载免费PDF全文
The title complex of [Ni2(µ‐Sal)4(Dena)2]H2O, [( µ‐tetrakissalicylato‐κ‐O,O)(bis‐N,N‐diethylnicotinamide‐κ‐N)(binickel(II))]hydrate, C48H52Ni2N4O16, has been synthesized and explained as structural using some elemental analysis, FT‐IR spectra, UV‐Vis reflectance, magnetic measurements, thermal analysis and x‐ray diffraction methods. The analysis results showed that the unit cell of complex includes two molecules NiII cation, four molecules salicylates as bridge and two molecules N,N‐diethylnicotinamide ligands, also there is one molecule hydrated aqua. The compound crystallizes in the monoclinic space group P21/c with the following unit‐cell parameters: a =13.6776(6) Å, b =10.5238(3) Å, c =21.8165(9), α=90.00°, β=126.546(3)°, γ=90.00º and Z=2. The compound [Ni2(µ‐Sal)4(Dena)2]H2O is a typical paddle‐wheel complex structure. Two NiII ions are bridged by four salicylate ligands (O2, O2i, O3, O3i, O5, O5i, O6 and O6i) using a µ‐COO? coordination mode [symmetry code: (i) 1‐x, 1‐y, 1‐z]. Each NiII also coordinates to one nitrogen atom (N1 and N1i) from one N,N‐diethylnicotinamide ligand molecule in the axial position. The complex has strong paramagnetic properties. 相似文献
94.
Dr. Gang Wang Yan Wu Dr. Zhujie Li Prof. Zaizhu Lou Qingqing Chen Yifan Li Prof. Dingsheng Wang Prof. Junjie Mao 《Angewandte Chemie (International ed. in English)》2023,62(13):e202218460
Developing highly efficient and stable photocatalysts for the CO2 reduction reaction (CO2RR) remains a great challenge. We designed a Z-Scheme photocatalyst with N−Cu1−S single-atom electron bridge (denoted as Cu-SAEB), which was used to mediate the CO2RR. The production of CO and O2 over Cu-SAEB is as high as 236.0 and 120.1 μmol g−1 h−1 in the absence of sacrificial agents, respectively, outperforming most previously reported photocatalysts. Notably, the as-designed Cu-SAEB is highly stable throughout 30 reaction cycles, totaling 300 h, owing to the strengthened contact interface of Cu-SAEB, and mediated by the N−Cu1−S atomic structure. Experimental and theoretical calculations indicated that the SAEB greatly promoted the Z-scheme interfacial charge-transport process, thus leading to great enhancement of the photocatalytic CO2RR of Cu-SAEB. This work represents a promising platform for the development of highly efficient and stable photocatalysts that have potential in CO2 conversion applications. 相似文献
95.
CONFIRM: connecting fragments found in receptor molecules 总被引:1,自引:0,他引:1
Thompson DC Denny RA Nilakantan R Humblet C Joseph-McCarthy D Feyfant E 《Journal of computer-aided molecular design》2008,22(10):761-772
A novel algorithm for the connecting of fragment molecules is presented and validated for a number of test systems. Within the CONFIRM (Connecting Fragments Found in Receptor Molecules) approach a pre-prepared library of bridges is searched to extract those which match a search criterion derived from known experimental or computational binding information about fragment molecules within a target binding site. The resulting bridge 'hits' are then connected, in an automated fashion, to the fragments and docked into the target receptor. Docking poses are assessed in terms of root-mean-squared deviation from the known positions of the fragment molecules, as well as docking score should known inhibitors be available. The creation of the bridge library, the full details and novelty of the CONFIRM algorithm, and the general applicability of this approach within the field of fragment-based de novo drug design are discussed. 相似文献
96.
Andrii V. Kulinich Nadezhda A. Derevyanko Alexander A. Ishchenko Stanislav L. Bondarev Valeri N. Knyukshto 《Journal of photochemistry and photobiology. A, Chemistry》2008,200(2-3):106-113
The fluorescent properties of a series of symmetric cationic cyanine dyes and merocyanines with trimethylene bridge connecting N-atom of the indole residue with α-position of the polymethine chain have been explored in detail. It is shown that the constraining group influences their fluorescent properties both by steric and electronic effects. It revealed an essential decrease of the fluorescence quantum yields of the constrained symmetric cyanine dyes in comparison with those of their analogues without bridge group in their chromophore. This effect diminishes essentially at polymethine chain lengthening. In the case of merocyanines the bridge group can cause a decrease as well a substantial increase of their fluorescence quantum yields depending on their type of solvatochromism and solvent polarity. The conclusions made on the basis of the experimental data are in good agreement with the results of semiempirical quantum-chemical calculations. 相似文献
97.
叶锦春 《数学年刊A辑(中文版)》2002,(6)
本文对带跳的耦合正倒向随机微分方程引入了“桥”的概念,证明了如果两个带跳的耦合正倒向随机微分方程被桥连接着,那么它们有相同的唯一可解性.在此基础上,通过桥的构造,得到一些带跳的正倒向随机微分方程的唯一可解性. 相似文献