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排序方式: 共有206条查询结果,搜索用时 15 毫秒
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G. A. Van Fo Fy 《Mechanics of Composite Materials》1966,2(5):478-483
A method has been developed for theoretically determining the physico-mechanical properties of glass-reinforced plastics (GRP) with hollow fibers. Approximate formulas for the rapid determination of the principal mechanical characteristics are derived.Mekhanika Polimerov, Vol. 2, No. 5, pp. 763–772, 1966 相似文献
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G. A. Van Fo Fy 《Mechanics of Composite Materials》1965,1(2):49-53
The basic relations of the theory of anisotropic creep of unidirectional glass-reinforced plastics (GRPs) in a three-dimensional stress state are found using a model of a material with inhomogeneous structure and the rheological properties of the resin. These relations are suitable for investigating the stress state of GRPs for resin stresses not exceeding certain values. The phenomena of simple creep and stress relaxation are studied with reference to a unidirectional GRP with an epoxy-maleic resin matrix.Mekhanika Polimerov, Vol. 1, No. 2, pp. 64–69, 1965 相似文献
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S.?AliEmail author A.?Fo?ner W.?Jing 《Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)》2018,53(1):27-33
Let B(H) be the algebra of all bounded linear operators on a complex Hilbert space H and A(H) ? B(H) be a standard operator algebra which is closed under the adjoint operation. Let F: A(H)→ B(H) be a linear mapping satisfying F(AA*A) = F(A)A*A + Ad(A*)A + AA*d(A) for all A ∈ A(H), where the associated linear mapping d: A(H) → B(H) satisfies the relation d(AA*A) = d(A)A*A + Ad(A*)A + AA*d(A) for all A ∈ A(H). Then F is of the form F(A) = SA ? AT for all A ∈ A(H) and some S, T ∈ B(H), that is, F is a generalized derivation. We also prove some results concerning centralizers on A(H) and semisimple H*-algebras. 相似文献
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Ying Han Yumeng Fei Mingxin Wang Yingang Xue Hui Chen Yuxuan Liu 《Molecules (Basel, Switzerland)》2021,26(14)
Bisphenol Z (BPZ), bisphenol S (BPS), bisphenol C (BPC), and bisphenol F (BPF) had been widely used as alternatives to bisphenol A (BPA), but the toxicity data of these bisphenol analogues were very limited. In this study, the joint toxicity of BPZ, BPS, BPC, and BPF to zebrafish (Danio rerio) was investigated. The median half lethal concentrations (LC50) of BPZ, BPS, BPC, and BPF to zebrafish for 96 h were 6.9 × 105 µM, 3.9 × 107 µM, 7.1 × 105 µM, and1.6 × 106 µM, respectively. The joint toxicity effect of BPF–BPC (7.7 × 105–3.4 × 105µM) and BPZ–BPC (3.4 × 105–3.5 × 105µM) with the same toxic ratio showed a synergistic effect, which may be attributed to enzyme inhibition or induction theory. While the toxicity effect of the other two bisphenol analogue combined groups and multi-joint pairs showed an antagonistic effect due to the competition site, other causes need to be further explored. Meanwhile, the expression levels of the estrogen receptor genes (ERα, ERβ1) and antioxidant enzyme genes (SOD, CAT, GPX) were analyzed using a quantitative real-time polymerase chain reaction in zebrafish exposure to LC50 of BPZ, BPS, BPC, and BPF collected at 24, 48, 72, and 96 h. Relative expression of CAT, GPX, and ERβ1 mRNA declined significantly compared to the blank control, which might be a major cause of oxidant injury of antioxidant systems and the disruption of the endocrine systems in zebrafish. 相似文献
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A novel ZnCo2O4/Bi2O3 heterojunction photocatalyst was prepared via balling method. The enhanced photocatalytic activity is mainly attributed to the broad photoabsorption and low recombination rate of photogenerated electron-hole pairs, which is driven by the photogenerated potential difference formed at the ZnCo2O4/Bi2O3 heterojunction interface. 相似文献
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Qianqian Gao Dr. Yumeng Zhao Kangli Xu Dr. Chao Zhang Dr. Qian Ma Liqing Qi Dandan Chao Tingting Zheng Linlin Yang Dr. Yanyan Miao Prof. Da Han 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23770-23774
A single-step method for isolation of specific cells based on multiple surface markers will have unique advantages because of its scalability, efficacy, and mildness. Herein, we developed multi-aptamer-mediated proximity ligation method on live cell membranes that leverages a multi-receptor co-recognition design for enhanced specificity, as well as a robust in situ signal amplification design for improved sensitivity of cell isolation. We demonstrated the promising efficacy of our method on differentiating tumor cell subtypes in both cell mixtures and clinical samples. Owing to its simple and fast operation with excellent cell isolation sensitivity and accuracy, this approach will have broad applications in biological science, biomedical engineering, and personalized medicine. 相似文献
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