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排序方式: 共有98条查询结果,搜索用时 15 毫秒
1.
Guo Lan Guan Yali Liu Peng Gao Linghuan Wang Zhifu Huang Shengli Peng Liang Zhao Zhiyu 《Cellulose (London, England)》2022,29(3):1315-1330
Cellulose - Extracellular vesicles are membrane-packed entities that are involved in various physiological and pathological processes. Recently, the role of exosomes and microvesicles in... 相似文献
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本文综述了几种具有典型几何形状的纳米氧化铝(主要包括球形、片状和一维线状以及棒状)的形貌与性质的关系.分析了控制这些形貌的制备方法,概括总结了各种形状纳米氧化铝的用途和发展前景. 相似文献
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Nan Wen Bojun Jiang Xiaojing Wang Zhifu Shang Dawei Jiang Lu Zhang Caiying Sun Zijian Wu Hui Yan Chuntai Liu Zhanhu Guo 《Chemical record (New York, N.Y.)》2020,20(8):773-792
The properties of polyvinyl alcohol (PVA) nanocomposite hydrogels influenced by nanoparticles are reviewed. Various kinds of nanoparticles with excellent mechanical and electrical properties have been introduced into PVA hydrogel to produce stretchable and conductive PVA nanocomposite hydrogel. Understanding the mechanism between the matrix of PVA hydrogel and nanoparticles is therefore critical for the development of PVA nanocomposite hydrogels. This review focuses on the nanoparticles include carbon nanotubes, graphene oxide and metal nanoparticles, and describes the effects of nanoparticles on the mechanical and conductive properties of PVA nanocomposite hydrogels. A new promising area of soft stretchable PVA nanocomposite hydrogel is highlighted for possible applications. Finally, a brief outlook for future research is presented. 相似文献
5.
Zhifu Xie 《Physics letters. A》2011,375(39):3392-3398
This Letter is to provide a new approach to study the phenomena of degeneracy of the number of the collinear central configurations under geometric equivalence. A direct and simple explicit parametric expression of the singular surface H3 is constructed in the mass space (m1,m2,m3)∈3(R+). The construction of H3 is from an inverse respective, that is, by specifying positions for the bodies and then determining the masses that are possible to yield a central configuration. It reveals the relationship between the phenomena of degeneracy and the inverse problem of central configurations. We prove that the number of central configurations is decreased to 3!/2−1=2, m1, m2, and m3 are mutually distinct if m∈H3. Moreover, we know not only the number of central configurations but also what the nonequivalent central configurations are. 相似文献
6.
Zhifu Jiang Jian Zhao Beibei Gao Shuo Chen Wenyan Qu Xiangdong Mei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1026-1037
Abstract A series of novel (4′-tosyl) piperidin-4-yl containing α-aminophosphonates were synthesized by a one-pot reaction, efficiently catalyzed by magnesium perchlorate, under solvent-free conditions from 1-tosylpiperidin-4-one, substituted aromatic amines, and diethyl phosphite (DEP). The synthesized compounds were characterized by IR, 1H NMR, 13C NMR, 31P NMR, and HRMS spectroscopy. A single-crystal X-ray structure of diethyl 4-(2-chlorophenyl) amino-1-(4’-methylbezenesulfonyl) piperidin-4-yl-phosphonate (2a) was obtained, and some of the title compounds displayed insecticidal activities against Plutella xylostella. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables. 相似文献
7.
Zhifu Liu Qinghong Zhang Yaogang Li Hongzhi Wang 《Journal of Physics and Chemistry of Solids》2012,73(5):651-655
Pencil-like ZnO microrods was synthesized via a simple solvothermal process in an aqueous solution of ethylenediamine and ethanolamine. The as-prepared ZnO was characterized by X-ray powder diffraction, field-emission scanning electron microscopy, room temperature photoluminescence spectra and UV–vis absorption spectra. The results indicated that ZnO microrods had the length in the range of 1.3–25 μm. The photocatalytic activity was studied by degradation of methylene blue (MB) aqueous solution, which showed that the as-prepared ZnO microrods possessed a high photocatalytic activity. The formation mechanism of the pencil-like ZnO was also investigated based on the experimental results. 相似文献
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Let G be a graph. The Hosoya index Z(G) of a graph G is defined to be the total number of its matchings. In this paper, we characterize the graph with the smallest Hosoya index of bicyclic graphs with given pendent vertices. Finally, we present a new proof about the smallest Hosoya index of bicyclic graphs. 相似文献
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In this paper, we consider the problem of central configurations of the n-body problem with the general homogeneous potential 1/rα. A configuration q=(q1,q2,…,qn) is called a super central configuration if there exists a positive mass vector m=(m1,…,mn) such that q is a central configuration for m with mi attached to qi and q is also a central configuration for m′, where m′≠m and m′ is a permutation of m. The main discovery in this paper is that super central configurations of the n-body problem have surprising connections with the golden ratio φ. Let r be the ratio of the collinear three-body problem with the ordered positions q1, q2, q3 on a line. q is a super central configuration if and only if 1/r1(α)<r<r1(α) and r≠1, where r1(α)>1 is a continuous function such that , the golden ratio. The existence and classification of super central configurations are established in the collinear three-body problem with general homogeneous potential 1/rα. Super central configurations play an important role in counting the number of central configurations for a given mass vector which may decrease the number of central configurations under geometric equivalence. 相似文献