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排序方式: 共有6543条查询结果,搜索用时 78 毫秒
1.
Gong Hengfeng Xiao Hong Wu Hailong Meng Fanliang Ren Qisen Liao Yehong Zhang Guoliang 《The European Physical Journal B - Condensed Matter and Complex Systems》2022,95(8):1-7
The European Physical Journal B - Molecular dynamics and Monte Carlo methods are common measurements to study the diffusion coefficients of the fluid particles under restricted conditions. Here,... 相似文献
2.
Yin Qingqing Xu Fen Sun Lixian Li Yaying Liao Lumin Wang Tao Guan Yanxun Xia Yongpeng Zhang Chenchen Wei Sheng Zhang Huanzhi Li Bin 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6583-6592
Journal of Thermal Analysis and Calorimetry - Polyethylene glycol (PEG) is widely used as phase change materials (PCMs). However, the leakage and low thermal conductivity issues restrict its... 相似文献
3.
近年来,设计和合成高性能非富勒烯受体(NFAs)材料已经成为太阳能电池研究领域的前沿课题。基于DA'D型稠环结构的NFAs由于具有吸光系数高、能级和带隙可调、结构易于修饰、分子可高效合成、光电学性能优异等优点而受到了越来越广泛的关注。在短短7年的时间里,能量转换效率(PCE)从3%~4%提高到18%。2019年初邹应萍等报道了一个优秀的受体分子Y6,与PM6共混制备单结电池,获得了15.7%的能量转换效率。Y6类受体材料的中心给电子单元为DA'D型稠环结构,缺电子单元(A')通过氮原子与两个给电子单元(D)并联形成稠环结构,这有助于降低前线分子轨道能级并增强吸收,同时与氮相连的两个烷基链和位于噻吩并噻吩β位的两个侧链则有助于提高溶解度及调节结晶性。自Y6问世以来,人们对分子的结构剪裁进行了深入的研究,并报道了数十种新的结构。在这些新的受体中,DA'D部分的结构裁剪对提高器件效率和太阳能电池的性能起着至关重要的作用。本文对A'、D单元和侧链结构修饰的研究进展进行了综述。通过选择几组受体,对最近报道的分子进行分类,并将它们的光学、电化学、电学和光电性质与精确的结构修饰相关联,从而对结构-性能关系进行全面概述。 相似文献
4.
Nonlinear Dynamics - Global dynamics of a flexible asymmetrical rotor resting on vibrating supports is investigated. Hamilton’s principle is used to derive the partial differential governing... 相似文献
5.
Jie Wang Cuicui Ma Qiannan Li Xing Wang Yang Yang Lingjian Yang Wei Jiang Sha Liao Shixiang Wang Pu Jia Ye Zhao Xiaohui Zheng 《Biomedical chromatography : BMC》2019,33(3)
Tanshinol borneol ester (DBZ) is a potential drug candidate composed of danshensu and borneol. It shows anti‐ischemic and anti‐atherosclerosis activity. However, little is known about its metabolism in vivo. This research aimed to elucidate the metabolic profile of DBZ through analyzing its metabolites using high‐performance liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight mass spectrometry. Chromatographic separation was performed on an Agilent TC‐C18 column (150 × 4.6 mm, 5.0 μm) with gradient elution using methanol and water containing 0.2% (v/v) formic acid as the mobile phase. Metabolite identification involved analyzing the retention behaviors, changes in molecular weights and MS/MS fragment patterns of DBZ and its metabolites. As a result, 20 potential metabolites were detected and tentatively identified in rat plasma, urine and feces after administration of DBZ. DBZ could be metabolized to O‐methylated DBZ, DBZ‐O‐glucuronide, O‐methylated DBZ‐O‐glucuronide, hydroxylated DBZ and danshensu. Danshensu, a hydrolysis product of DBZ, could further be transformed into 12 metabolites. The proposed method was confirmed to be a reliable and sensitive alternative for characterizing metabolic pathways of DBZ and providing valuable information on its druggability. 相似文献
6.
Dr. Wenyan Hao Yuchen Sha Dr. Yi Deng Yi Luo Li Zeng Shan Tang Dr. Yue Weng Prof. Dr. Chien-Wei Chiang Prof. Dr. Aiwen Lei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):4931-4934
An in situ generated oxidation species of nickel quinolinylpropioamide intermediate was produced. Characterization by X-ray absorption near edge structure (XANES) and EPR provides complementary insights into this oxidized nickel species. With aliphatic amides and isocyanides as substrates, a nickel-catalyzed facile synthesis of structurally diverse five-membered lactams could be achieved. 相似文献
7.
In this paper, the existence and multiplicity of positive solutions is established for Schrödinger‐Poisson system of the form where 0 ∈ Ω is a smooth bounded domain in , , and λ > 0 is a real parameter. Combining with the variational method and Nehari manifold method, two positive solutions of the system are obtained. 相似文献
8.
Yonghui Liu Huaying Gao Xiaoli Sheng Yuming Zhou Beibei Wang Xiao Sha Maolu Jin Jie Zhao Wenqi Liu 《应用有机金属化学》2019,33(11)
In this work, a series of novel acidic polymerized ionic liquids were used as heterogeneous catalyst for alkylation of o‐Xylene with styrene. And the effect of the amount of initiator and the type of acid used for ion exchange on catalyst structure and the catalytic performance of catalysts for alkylation were studied thoroughly. The experiment results show: when the percentage of the amount of initiator in the total material is 3%, the polymerized ionic liquid catalyst MPM‐SO3H‐[C3V][SO3CF3] has the most uniform with a specific surface area of 97.30 m2/g and a pore volume of 0.35 cm3/g. Benefiting from the unique structure features, MPM‐SO3H‐[C3V][SO3CF3] manifested an excellent catalytic performance for alkylation of o‐Xylene with styrene, along with the conversion of styrene was 96.8% and the yield of 1‐Phenyl‐1‐ortho‐xylene ethane was 94.7%. Therefore, this work provides a novel reference to the synthesis of polymerized ionic liquids and clearly explains the advantage of novel acidic polymerized ionic liquids on alkylation. 相似文献
9.
Wenyuan Xu Yan Wang Suying Li Yongbing Cheng Zanru Guo Lin Hu Mengyin Liao Jiaxi Peng Xi Chen Shaoming Yang 《应用有机金属化学》2021,35(1)
Dimethyldichlorosilane, one of the most consumed organosilicon monomers in the industry, can be prepared in a highly efficient and environmentally friendly synthesis method of disproportionating methylchlorosilanes. However, the internal mechanism of the reaction remains unclear. In this paper, the mechanism catalyzed by AlCl3/MIL‐53(Al) and AlCl3/MIL‐53(Al)@γ‐Al2O3 catalysts was calculated at B3LYP/6‐311++G(3df, 2pd) level by using the density functional theory (DFT). The results showed that although the two catalysts had similar active structures, the catalytic effects were significantly different. The Lewis acid center on the surface of γ‐Al2O3 in the core‐shell catalyst is complementary to the classic Lewis acid AlCl3 through the spatial superposition effect, which greatly improves the Lewis acid catalytic activity of AlCl3/MIL‐53(Al)@γ‐Al2O3. 相似文献
10.
磷酸酯类前药与原药相比,不仅能够提高药物靶向性、稳定性和生物利用度,减少药物毒副作用,还能掩蔽药物不适气味、提高水溶性从而改善给药途径。含羟基药物的磷酸酯化是该类药物前药设计的重要方法之一。本文根据中心磷原子的价态和化合物结构进行分类,综述了各种P(Ⅴ)四配位分子、P(Ⅲ)三配位分子和H-亚磷酸酯类化合物作为磷酸酯化试剂在磷酸酯类前药合成方法中的研究进展,并阐述了这些磷酸酯类药物的应用,最后总结了各类磷酸酯化试剂的优势与局限,并结合连续流反应技术应用案例展望了其发展趋势。 相似文献