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41.
介绍了运用3DS MAX 5制作分子和离子结构模型及其动画,以及用动画演示化学反应机理的方法。 相似文献
42.
药物分子对接中应用网格的研究与进展 总被引:6,自引:0,他引:6
药物分子对接所涉及的搜索空间非常巨大,需要耗费大量的时间,并且对计算环境也有较高的要求.将网格技术应用于药物分子对接中,能有效地解决上述问题.首先对分子对接理论做了简单介绍;然后,利用网格数据传输和网格任务调度等网格技术对分子对接过程进行了优化,有效利用了网格结点资源,并降低了药物分子的对接时间;最后的实例测试表明了药物分子对接与网格技术相结合的合理性及有效性. 相似文献
43.
从氢原子质子化模型计算H2+的结构参数 总被引:2,自引:0,他引:2
对氢分子离子提出了氢原子质子化的结构模型,从微观时标和宏观时标分析了H2+中库仑吸引力和两核排斥力的动态平衡,认为氢原子畸变后的电子云在两核中点产生e/8的电荷重心时可以束缚住一个裸质子;据此推导出键长、键能及力常数的计算公式;使用原子单位分别获得Re=2 au,De=0.109 735 au,k=0.109 735 au,与实验测定值及Bishop最精确的计算值惊人地接近。 相似文献
44.
Two new oligothiophene-based small molecules, namely DRCN6T-F and DRCN8T-F, with 3,3′-difluoro-2,2′-bithiophene as the central building block and 2-(1,1-dicyanomethylene)-rhodanine as end groups, were designed and synthesized. Compared to their non-fluorinated counterparts DRCN6T and DRCN8T, DRCN6T-F and DRCN8T-F exhibit enhanced intermolecular interactions and lower HOMO energy levels. However, PCEs of 2.26% and 5.07% were obtained for DRCN6T-F and DRCN8T-F based optimized devices, respectively, lower than those of non-fluorinated molecules DRCN6T and DRCN8T. The relatively poor performance for the DRCN6T-F and DRCN8T-F were mainly caused by their low short-circuit current densities, due to their unfavorable morphologies and low charge carrier mobilities. 相似文献
45.
Anton Kurz Jürgen J. Schmied Kristin S. Grußmayer Phil Holzmeister Philip Tinnefeld Dirk‐Peter Herten 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(23):4061-4068
Obtaining quantitative information about molecular assemblies with high spatial and temporal resolution is a challenging task in fluorescence microscopy. Single‐molecule techniques build on the ability to count molecules one by one. Here, a method is presented that extends recent approaches to analyze the statistics of coincidently emitted photons to enable reliable counting of molecules in the range of 1–20. This method does not require photochemistry such as blinking or bleaching. DNA origami structures are labeled with up to 36 dye molecules as a new evaluation tool to characterize this counting by a photon statistics approach. Labeled DNA origami has a well‐defined labeling stoichiometry and ensures equal brightness for all dyes incorporated. Bias and precision of the estimating algorithm are determined, along with the minimal acquisition time required for robust estimation. Complexes containing up to 18 molecules can be investigated non‐invasively within 150 ms. The method might become a quantifying add‐on for confocal microscopes and could be especially powerful in combination with STED/RESOLFT‐type microscopy. 相似文献
46.
47.
Guomin Yu Pei Tian Kexin Ren Wenchao Wu Zhenxi Zhang Zhenbin Gong Junyan Zhang 《Ceramics International》2021,47(15):21325-21333
The establishment of superlow friction in moist air is very important for the engineering application of hydrogenated diamond-like carbon (H-DLC) films. Nevertheless, water molecules in the surrounding atmosphere always result in the failure of the near-frictionless state. This work aims to explore the effects of water molecules in the environment and the material of the counterparts on the tribological performance of a composite structure prepared by depositing MoS2 on a H-DLC film. The results indicated that the existence of water molecules in the atmosphere is beneficial for achieving stable superlubricity for the material system because it helps retain the in-situ formed MoS2 transfer film on the counterpart. In the presence of water molecules, the wear interface was replaced by a robust and incommensurate MoS2 tribolayer/H-DLC sliding interface, which was responsible for the superlow friction achieved in this work. The results also revealed that the ZrO2 counterpart was capable of retaining the as-formed MoS2 transfer film and establishing long-lasting superlow friction even in dry air. The mechanisms behind this phenomenon are also discussed in this paper. 相似文献
48.
We demonstrate a planar organic solar cell with a four-layer cascade architecture that exhibits an open-circuit voltage (Voc) greater than the offset in energy between the highest occupied molecular orbital (HOMO) of the outermost donor and the lowest unoccupied molecular orbital (LUMO) of the outermost acceptor. The device consists of a subphthalocyanine (SubPc)/fullerene (C60) heterojunction that is modified by inserting one or two additional donor layers between SubPc and the anode. We find that two-, three- and four-layer structures yield similar Voc (1.0 V, 0.91 V and 0.94 V, respectively), even though the outermost HOMO-LUMO offset decreases from 1.4 eV to 1.10 eV, and to 0.9 eV, respectively. Analysis of the turn-on voltage in dark provides further evidence that open-circuit voltage is not limited by the outermost HOMO-LUMO offset. 相似文献
49.
White JB Beckford J Yadegarynia S Ngo N Lialiutska T d'Alarcao M 《Food chemistry》2012,131(4):1453-1459
A common feature of both apoptosis and inflammation is the activation of caspases. Caspases are aspartate-directed cysteine proteases that have numerous cellular targets. It has been discovered that several flavonoids are inhibitors of caspases. Flavonoids are members of a family of polyphenolic compounds from plants that have many biological properties, one of which is the ability to induce cell death. Some flavonoids are selective inhibitors of particular caspases. Since some of the inhibitory flavonoids are nevertheless cytotoxic, these results suggest that flavonoid-induced cell death may be occurring through a non-classical apoptosis pathway that is not dependent on caspase activity. 相似文献
50.
Hao-Wu Lin Hao-Wei Kang Zheng-Yu Huang Chang-Wen Chen Yi-Hong Chen Li-Yen Lin Francis Lin Ken-Tsung Wong 《Organic Electronics》2012,13(10):1925-1929
Novel organic/ultrathin low work function metal bilayer cathode buffers for small molecule organic solar cells are proposed. Ultrathin low work function metal layers possess a high built-in electric field for effective carrier extraction and a high cathode reflectivity for maximum absorption in the photoactive layers. This leads to a significant increase of short circuit current density and fill factor of cells. By integrating this bilayer cathode buffer with DTDCTB:C60 small molecular heterojunction, the device exhibits a high power conversion efficiency of up to 5.28%, which is an improvement of 22% compared to a device with a traditional single organic layer buffer. 相似文献