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991.
Jonathan A. Yoffe 《Theoretical chemistry accounts》1979,51(2):137-144
Molecular interactions may be broken up into the interaction of bonds and inner shells. Results for bond and inner shell interaction coefficients for pairwise additive termsC
6,C
8,C
10 andd
4 are given, as well as the non-(pairwise) additive coefficient 3. Simple combination rules may be used to estimate these terms with good results. Parameters should be applicable to macromolecules. 相似文献
992.
Cylindrical shells produced by single-layer or cross winding are analyzed for stability. An approximate analytical solution
is proposed. It allows evaluating the effect of an unbalanced laminate on the critical values of the axial load, intensity
of external pressure, and shear forces. It is shown that the effect of imbalance weakens with increase in the number of laminas.
In each specific case, the number of laminas at which the material can be considered orthotropic is determined
__________
Translated from Prikladnaya Mekhanika, Vol. 41, No. 6, pp. 113–120, June 2005. 相似文献
993.
报道了具有核壳结构的Fe3 O4 聚苯胺磁性纳米微球的合成方法和表征结果 .微球同时具有导电性和磁性能 .在优化的实验条件下 ,可得到饱和磁化强度Ms 为 5 5 .4emu/g ,矫顽力Hc 为 6 2Oe的磁性微球 .微球的导电性随着微球中Fe含量的增加而下降 .微球的磁性能则随着Fe含量的增加而增大 .Fe3 O4 磁流体的粒径和磁性聚苯胺微球的粒径均在纳米量级 .纳米Fe3 O4 粒子能够提高复合物的热性能 .实验表明 ,磁流体和聚苯胺之间可能存在着一定的相互作用 ,但这种相互作用较为复杂 ,难于研究 . 相似文献
994.
Multiobjective optimization of the structure and geometry of a laminated anisotropic composite shell with an elastic core under thermal action is considered. The thermoelastic properties of the laminated composite are determined from the known properties of the monolayer and the given values of the variable structural and geometric parameters. The properties to be optimized - the critical load and thermal stresses - depend on two variable parameters, the stochastic properties of the composite, and the temperature. In the space of the properties being optimized, the domain of allowable solutions and the property scatter ellipses for the optimum compromise project are found. The reliability of the project is determined with regard for the correlation between the critical and thermal stresses. 相似文献
995.
996.
Controlled Formation of TiO2/MoS2 Core–Shell Heterostructures with Enhanced Visible‐Light Photocatalytic Activities
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Chuanxi Wang Huihui Lin Zhenyu Liu Jiapeng Wu Zhenzhu Xu Chi Zhang 《Particle & Particle Systems Characterization》2016,33(4):221-227
Most recently, much attention has been devoted to photocatalytic materials that may help to solve the global energy crisis and may provide environmental protection. Herein, novel cocatalysts based on few layered MoS2 and TiO2 nanomaterials have been designed by growing MoS2 nanosheets on the surface of TiO2 nanospheres through a facile hydrothermal method. The method allows the formation of TiO2/MoS2 core–shell heterostructures of uniform morphologies and stable structure and provides a good control over shell thickness. The mechanism that forms these heterostructures is discussed in detail. In addition, as cocatalyst, MoS2 nanosheets can enlarge the light harvesting window to include visible light and improve the photocatalytic ability of TiO2. Using Rhodamine B as the model, the resultant heterostructure is demonstrated to possess excellent and stable photocatalytic activity in the degradation of organic pollutants under visible light illumination. The TiO2/MoS2 heterostructures possess this catalytic activity due to their large surface area and their excellent interface for separating holes and electrons. Therefore, this novel heterostructure nanomaterials possess potential applications in water treatment, degradation of dye pollutants, and environmental cleaning. 相似文献
997.
A New Method for Determining the Composition of Core–Shell Nanoparticles via Dual‐EDX+EELS Spectrum Imaging
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David Rossouw Benjamin R. Knappett Andrew E. H. Wheatley Paul A. Midgley 《Particle & Particle Systems Characterization》2016,33(10):749-755
Simultaneously acquired microanalytical X‐ray and electron energy loss signals are obtained from a bimetallic core–shell nanoparticle system (FePt@Fe3O4). The signals are decomposed using independent component analysis and the extracted components are used to separately quantify the composition of the spatially overlapping core and shell phases in the nanoheterostructure. The utilization of the complementary strengths of energy dispersive X‐ray and electron energy‐loss spectroscopy microanalysis has enabled the quantification of both light and heavy elements in a single spectrum image acquisition. 相似文献
998.
(Au)核(Ag)壳纳米微粒光度法快速检测过氧化氢 总被引:3,自引:0,他引:3
以粒径为10 nm的纳米金为晶种, 用柠檬酸钠还原硝酸银制备了平均粒径为30 nm的(Au)核(Ag)壳纳米微粒, 用高速离心纯化除去过量的柠檬酸三钠获得了较纯的(Au)核(Ag)壳纳米微粒, 其吸收峰位于393 nm处. 在pH 4.4的HAc-NaAc缓冲溶液中, Fenton反应产生的羟基自由基可以氧化(Au)核(Ag)壳纳米微粒银层生成银离子, 导致393 nm处的吸光度降低. H2O2的浓度(c)在6.58~421.1 μmol/L范围内与393 nm处的吸光度降低值ΔA 393 nm呈良好的线性关系, 回归方程为ΔA393 nm=0.00111c+0.0210, 相关系数为0.9908, 检出限为1.73 μmol/L. 本方法用于废水样品测定, 结果满意. 相似文献
999.
Xuejun Cui Shuangling Zhong Yan Gao Hongyan Wang 《Colloids and surfaces. A, Physicochemical and engineering aspects》2008,324(1-3):14-21
The emulsifier-free core–shell interpenetrating polymer network (IPN) fluorinated polyacrylate latex particles with fluorine rich in shell were prepared by emulsifier-free seeded emulsion polymerization with water as the reaction medium. The fluorinated copolymer could be fixed on the particle surface due to the formation of interpenetrating polymer network. The resultant core–shell particles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS) analysis, Fourier transform infrared (FTIR) spectrometry, X-ray photoelectron spectroscopy (XPS) analysis and thermogravimetric analysis (TGA). The core–shell particles possessed very narrow monomodal particle size distributions. XPS analysis of the latex film displayed that perfluoroalkyl groups had the tendency to enrich at surface and there was a gradient concentration of fluorine in the structure of the latex film from the film–air interface to the film–glass interface. In addition, compared with the latex film of crosslinked polyacrylate prepared under the same condition, the emulsifier-free core–shell IPN-fluorinated polyacrylate latex film showed better thermal stability, higher contact angle and lower water uptake. 相似文献
1000.