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21.
Piao He Jian‐Guo Zhang Kun Wang Xin Yin Tong‐Lai Zhang 《Journal of Physical Organic Chemistry》2016,29(1):29-34
Two novel energetic nitrogen‐rich compounds 1,4‐diaminotetrazol‐5‐one ( DATO ) and 1,4‐dinitrotetrazol‐5‐one ( DNTO ) were proposed first and studied by quantum chemistry method with B3LYP/6‐31G* level of theory. The optimized geometry, IR predicted spectrum and thermochemical parameters, frontier molecular orbitals and molecular electrostatic potential were calculated for inspecting the electronic structure, molecular stability and chemical reactivity. The important macroscopic properties including density, enthalpy of formation, detonation parameters and impact sensitivity have been predicted as well. As a result, two designed compounds DATO and DNTO possess positive enthalpy of formation (395.79 and 342.77 kJ/mol), impressive detonation parameters (D = 8.80 km/s, P = 33.69 GPa; D = 8.89 km/s, P = 34.98 GPa) superior to the remarkable explosive RDX, acceptable sensitivities and might be promising candidates of energetic materials. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
22.
This paper presents an electrical actuation scheme of dielectric droplet by negative liquid dielectrophoresis. A general model of lumped parameter electromechanics for evaluating the electromechanical force acting on the droplets is established. The model reveals the influence of actuation voltage, device geometry, and dielectric parameter on the actuation force for both conductive and dielectric medium. Using this model, we compare the actuation forces for four liquid combinations in the parallel-plate geometry and predict the low voltage actuation of dielectric droplets by negative dielectrophoresis. Parallel experimental results demonstrate such electric actuation of dielectric droplets, including droplet transport, splitting, merging, and dispending. All these dielectric droplet manipulations are achieved at voltages < 100 Vrms. The frequency dependence of droplet actuation velocity in aqueous solution is discussed and the existence of surfactant molecules is believed to play an important role by realigning with the AC electric field. Finally, we present coplanar manipulation of oil and water droplets and formation of oil-in-water emulsion droplet by applying the same low voltage. 相似文献
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Piao He Jian‐Guo Zhang Li‐Na Feng Kun Wang Tong‐Lai Zhang Shao‐Wen Zhang 《Journal of Physical Organic Chemistry》2015,28(6):423-427
1,5‐Daminotetrazole (DAT) is of much interest because of the practical significance and the diversity of characteristics. The study on the decomposition pathway and the kinetics of DAT has been performed based on the quantum chemistry theory. The minimum energy path (MEP) calculation has shown that NH2N3 and NH2CN are the initially detected products of DAT. And the structures of reactant, products and transition state were optimized with MP2 methods using 6‐311G** basis sets, and the energies were refined using CCSD(T)/6‐311G** levels of theory. The calculated rate constants were obtained using the conventional transition‐state theory (TST) and the canonical variational transition‐state theory (CVT) methods. The calculation results indicated that the energy barrier of decomposition reaction is 47.98 kcal mol?1 and the variational effect is small. In addition, the rate constants and the Arrhenius experience formula of DAT decomposition have been obtained between 200 and 2500 K temperature regions. The fitted three‐parameter expressions calculated using the TST and CVT methods are (TST) and (CVT). This work may provide the theoretical support for further experimental synthesis and testing. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
25.
Chao Wang Jiafang Piao Yujie Li Xiancheng Tian Yuanchen Dong Dongsheng Liu 《Angewandte Chemie (International ed. in English)》2020,59(35):15176-15180
The shape of eukaryotic cells is determined by the cytoskeleton associated with membrane proteins; however, the detailed mechanism of how the integral morphologies with structural stability is generated and maintained is still not fully understood. Here, based on the Frame‐Guided Assembly (FGA) strategy, we successfully prepared hetero‐liposomes with structural composition similar to that of eukaryotic cells by screening a series of transmembrane peptides as the leading hydrophobic groups (LHGs). It was demonstrated that the conformation and transmembrane mode of the LHGs played dominant roles during the FGA process. The FGA liposomes were formed with excellent stability, which may further provide evidence for the cytoskeleton–membrane protein–lipid bilayer model. Taking advantage of the biocompatibility and stability, the FGA liposomes were also applied to prepare novel drug delivery vehicles, which is promising in diagnostic imaging and cancer therapy applications. 相似文献
26.
组合生成算法与多元线性回归相结合用于近红外光谱波长的优选 总被引:6,自引:0,他引:6
分立波长型近红外光谱分析仪是光谱分析仪器中较为普及的一种快速成份定量分析仪。如滤光片型、发光二极管型等。该类分析仪器研发的一个主要问题是如何针对于待测物质主要成份进行近红外光谱解析。找到最优定标波长组合用于建立稳健的定标模型。常用的波长选择方法为相关光谱结合逐步多元线性回归方法,该方法依据各参与定标波长所对应的t检验值进行最优定标波长的判别,但在实际应用中定标模型的定标精度和预测精度相差较大,具有很大的不准确性。为了实现定标波长的优选引入了组合数学中的组合生成算法。可以在较短的时间内完成最优波长组合的选取,结果是令人满意的。 相似文献
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蛋白酪氨酸磷酸酶1B(PTP1B)作为胰岛素和瘦素信号转导通路的负调节因子,已成为治疗糖尿病和肥胖症的潜在靶标.为了寻找非磷酸酯类PTP1B抑制剂,设计、合成了一系列含3,4-二氢-2(1H)-喹啉酮结构的新型查尔酮衍生物,并对化合物进行了PTP1B抑制活性测定.结果显示,所有化合物对PTP1B均显示出较强的抑制活性,其中化合物(E)-6-{4-[3-(4-氯苯基)-3-氧代-1-丙烯基]苄氧基}-3,4-二氢-2(1H)-喹啉酮(4e)和(E)-6-{4-[3-(3-溴苯基)-3-氧代-1-丙烯基]苄氧基}-3,4-二氢-2(1H)-喹啉酮(4i)活性最佳,IC50分别为(4.64±0.38)和(4.36±0.41)μmol/L. 相似文献
29.
采用室温离子热法合成了一种氟取代的具有五重贯穿金刚石拓扑结构的三维共价有机骨架材料(COFs), 记为JUC-515. 与高温溶剂热法不同的是, 室温离子液体法具有反应温度和压力低、 反应时间短、 操作简单、 无需催化剂和不产生有机蒸汽污染等优势. 制备的材料具有高度结晶性、 较大的孔隙率和良好的CO2选择性吸附性能. 相似文献
30.