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排序方式: 共有156条查询结果,搜索用时 109 毫秒
1.
Guoyu Wei Yuexiang Lu Shuang Liu Hongpeng Li Xuegang Liu Gang Ye Jing Chen 《中国化学快报》2021,32(1):497-500
Metal organic frameworks(MOFs) are a kind of promising materials in many applications,while the fast and controllable synthesis of MOFs is still challenging.Here,taking HKUST-1 as illustration,a microplasma electrochemistry(MIPEC) strategy was developed to accelerate the synthesis process of MOFs with micro-plasma acting as cathode.Treating the HKUST-1 precursor solution with micro-plasma cathode could not only transfer the electrons into the solution leading to the deprotonation effect,but also generate radical species to trigger and accelerate the nucleation and growth of MOFs at the plasmaliquid interface.Thus,uniform and nanosize MOFs could be prepared within minutes.The obtained MOFs show similar excellent uranium adsorption properties compared with those obtained by other method,with a highly adsorption capability of uranium with 550 mg/g in minutes.The novel MIPEC strategy developed in this work provides an alternative for controllable synthesis of MOFs,and especially has potential application in accelerating traditional organic synthesis. 相似文献
2.
Poly(lactic acid) (PLA)/poly(?-caprolactone) (PCL)/nano-silica composite degradable films were prepared by a solvent casting method. SEM results showed that the nano-silica particles were dispersed uniformly in the PLA/PCL matrix. TGA results indicated that the thermal decomposition temperature rose with the increase of nano-silica content. The tensile strength of the composites was enhanced with the increase of nano-silica content up to 2%. The tensile strength increased with the silica content and reached its maximum (22.51 Mpa). The improvement in the water uptake ratio in the PLA/PCL/silica nanocomposites may be attributable to the presence of silica nanoparticles in the PLA/PCL matrix. After 15 weeks total processing time for the solution of alkaline and phosphate buffer, the performances of 16.23% and 3.65% for degradation. 相似文献
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4.
以广东某水坝为研究对象,给出一种基于Fluent平台和Ansys平台进行结构动力响应分析的方法。首先采用基于YOUNGS界面重构技术的VOF模型,对流动进行数值模拟,成功捕捉了闸门开启过程中自由面的变化,比较了在三种落差情况下水坝的受力差异。计算表明,即使在上游平稳的入流条件下,水坝所受到的湍流水压力也会出现波动现象,水压力对坝体的冲击为低频作用,下游水位的升高会减缓水压力的波动,这些特点都与现场观察的相符。然后将水动力作为激励条件导入结构动力分析平台Ansys后,进一步对坝体结构进行动力分析。结构的模态分析结果与实测结果一致。因此,方法可以应用于实际。 相似文献
5.
Wanhua Lei Dr. Guoyu Jiang Dr. Qianxiong Zhou Dr. Yuanjun Hou Prof. Baowen Zhang Prof. Xuexin Cheng Prof. Xuesong Wang 《Chemphyschem》2013,14(5):1003-1008
Nanoscaled coordination polymers based on biologically prevalent ions have potential applications in drug delivery and biomedical imaging. Herein, coordination polymer nanoparticles of anionic porphyrins, including meso‐tetra(4‐carboxyphenyl)‐porphyrin (H2TCPP4?) and meso‐tetra(4‐sulfonatophenyl)‐porphyrin (H2TPPS4?), and alkaline or alkaline earth metal cations, such as K+ and Ca2+, were constructed in aqueous solution in the presence of cucurbit[7]uril (CB7) or cucurbit[8]uril (CB8). UV/Vis absorption and fluorescence spectroscopy, dynamic light scattering (DLS), scanning electron spectroscopy (SEM), and atomic force microscopy (AFM) were applied to explore the assembly and particle formation of porphyrin anions and metal cations mediated by CBn. The particle size depends on the kinds of CBn and metal cations and their concentrations. The uptake of H2TPPS4? particles by tumor cells (A549 cells) was found to be more efficient than H2TPPS4? at 37 °C, showing the application potential of such assembled particles in biology and medicine. 相似文献
6.
Xie Puhui Zhu Yanru Huang Xuewei Gao Guangqin Guo Fengqi Yang Guoyu 《Research on Chemical Intermediates》2018,44(4):2823-2837
Research on Chemical Intermediates - A new near-infrared fluorescent “turn-on” chemodosimeter (probe 1) based on dicyanomethylene-4H-chromene fluorophore for sulfide was developed.... 相似文献
7.
Yao Zhang Jie Li Guoyu Ren Baofu Qin Haixia Ma 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(6):485-490
Azole compounds have attracted commercial interest due to their high bactericidal and plant‐growth‐regulating activities. Uniconazole [or 1‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H‐1,2,4‐triazol‐1‐yl)pent‐1‐en‐3‐ol] is a highly active 1,2,4‐triazole fungicide and plant‐growth regulator with low toxicity. The pharmacological and toxicological properties of many drugs are modified by the formation of their metal complexes. Therefore, there is much interest in exploiting the coordination chemistry of triazole pesticides and their potential application in agriculture. However, reports of complexes of uniconazole are rare. A new cobalt(II) complex of uniconazole, namely dichloridotetrakis[1‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H‐1,2,4‐triazol‐1‐yl‐κN4)pent‐1‐en‐3‐ol]cobalt(II), [CoCl2(C15H18ClN3O)4], was synthesized and structurally characterized by element analysis, IR spectrometry and X‐ray single‐crystal diffraction. The crystal structural analysis shows that the CoII atom is located on the inversion centre and is coordinated by four uniconazole and two chloride ligands, forming a distorted octahedral geometry. The hydroxy groups of an uniconazole ligands of adjacent molecules form hydrogen bonds with the axial chloride ligands, resulting in one‐dimensional chains parallel to the a axis. The complex was analysed for its antifungal activity by the mycelial growth rate method. It was revealed that the antifungal effect of the title complex is more pronounced than the effect of fungicide uniconazole for Botryosphaeria ribis, Wheat gibberellic and Grape anthracnose. 相似文献
8.
Naive Bayes (NB) is one of the most popular classification methods. It is particularly useful when the dimension of the predictor is high and data are generated independently. In the meanwhile, social network data are becoming increasingly accessible, due to the fast development of various social network services and websites. By contrast, data generated by a social network are most likely to be dependent. The dependency is mainly determined by their social network relationships. Then, how to extend the classical NB method to social network data becomes a problem of great interest. To this end, we propose here a network-based naive Bayes (NNB) method, which generalizes the classical NB model to social network data. The key advantage of the NNB method is that it takes the network relationships into consideration. The computational effciency makes the NNB method even feasible in large scale social networks. The statistical properties of the NNB model are theoretically investigated. Simulation studies have been conducted to demonstrate its finite sample performance. A real data example is also analyzed for illustration purpose. 相似文献
9.
Guoyu Zhang Song Zhou Dr. Liang Fu Dr. Pinhong Chen Prof. Yibiao Li Prof. Dr. Jianping Zou Prof. Dr. Guosheng Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20619-20624
The first copper-catalyzed asymmetric cyanation and etherification reactions of enamides have been established, where a carbon-centered radical adjacent to a nitrogen atom (CRAN) is enantioselectively trapped by a chiral copper(II) species. Moreover, the asymmetric cyanation of vinyl esters was disclosed as well. These reactions feature very mild reaction conditions and high functional group tolerance, and give a series of chiral α-cyano amides, α-cyano esters and α-hemiaminals in good yields with excellent enantioselectivity. The chiral α-cyano amides can be easily converted into enantioenriched 1,2-diamines and amino acids. 相似文献
10.
Julien P.A. Makongo Dinesh K. Misra James R. Salvador Nathan J. Takas Guoyu Wang Michael R. Shabetai Aditya Pant Pravin Paudel Ctirad Uher Kevin L. Stokes Pierre F.P. Poudeu 《Journal of solid state chemistry》2011,184(11):2948-2960
Bulk Zr0.25Hf075NiSn half-Heusler (HH) nanocomposites containing various mole fractions of full-Heusler (FH) inclusions were prepared by solid state reaction of pre-synthesized HH alloy with elemental Ni at 1073 K. The microstructures of spark plasma sintered specimens of the HH/FH nanocomposites were investigated using transmission electron microscopy and their thermoelectric properties were measured from 300 K to 775 K. The formation of coherent FH inclusions into the HH matrix arises from solid-state Ni diffusion into vacant sites of the HH structure. HH(1–y)/FH(y) composites with mole fraction of FH inclusions below the percolation threshold, y∼0.2, show increased electrical conductivity, reduced Seebeck coefficient and increased total thermal conductivity arising from gradual increase in the carrier concentration for composites. A drastic reduction (∼55%) in κl was observed for the composite with y=0.6 and is attributed to enhanced phonon scattering due to mass fluctuations between FH and HH, and high density of HH/FH interfaces. 相似文献