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71.
Cheng‐Ho Chen Chih‐Chun Teng Ming‐Shyong Tsai Fu‐Su Yen 《Journal of Polymer Science.Polymer Physics》2006,44(15):2145-2154
A Haake torque rheometer equipped with an internal mixer is used to study the influence of the amount of sodium montmorillonite (Na+‐MMT) and organically modified MMT (O‐MMT) on X‐ray diffraction (XRD), morphology, and mechanical characteristics of rigid poly (vinyl chloride) (PVC)/Na+‐MMT and PVC/O‐MMT nanocomposites, respectively. Results of XRD and transmission electron microscopy (TEM) indicate that MMT is partially encapsulated and intercalated in the rigid PVC/Na+‐MMT nanocomposites. However, results of XRD and TEM show MMT is partially intercalated and exfoliated in the rigid PVC/O‐MMT nanocomposites. Tensile strength, yield strength, and elongation at break of the rigid PVC/MMT nanocomposites were improved simultaneously with adding 1–3 wt % Na+‐MMT or O‐MMT with respect to that of pristine PVC. However, the addition of Na+‐MMT or O‐MMT should be kept as not more than 3 wt % to optimize the mechanical properties and the processing stability of the rigid PVC/MMT nanocomposites. SEM micrographs of the fractured surfaces of the rigid PVC/Na+‐MMT and PVC/O‐MMT nanocomposites both before and after tensile tests were also illustrated and compared. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2145–2154, 2006 相似文献
72.
Following a previous systematic theoretical study of the ground-state properties of over 7000 nuclei from the proton drip line to the neutron drip line in the relativistic mean field model [Prog. Theor. Phys. 113 (2005) 785], which is in fair agreement with existing experimental data, we observe a few spurious shell closures, i.e. proton shell closures at Z = 58 and Z = 92. These spurious shell closures are found to persist in all the effective forces of the relativistic mean field model, e.g. TMA, NL3, PKDD and DD-ME2. 相似文献
73.
In this paper, a quantum secure direct communication protocol using ensembles with the same density matrix is proposed. The two communication parties can realize the message transmission using this method through a quantum channel, each bit of information can be transmitted using an ensemble and read out through global measurement.The eavesdropping behavior can be detected through the channel diagnoses. 相似文献
74.
Retraction: The following article from Biomedical Chromatography, “Determination of scutellarin isomer, a predominant metabolite of scutellarin, in human plasma by HPLC/tandem mass spectrometry and its application to the pharmacokinetic study in Chinese healthy volunteers” by Chun‐hua Xia, Yu‐qing Xiong, and Guang‐ji Wang, published online on 21 June 2007 in Wiley Interscience (www.interscience.wiley.com/journal/bmc), has been retracted at the authors' request. 相似文献
75.
The authors consider the limiting behavior of various branches in a uniform recursive tree with size growing to infinity.The limiting distribution ofζ_(n,m),the number of branches with size m in a uniform recursive tree of order n,converges weakly to a Poisson distribution with parameter 1/m with convergence of all moments.The size of any large branch tends to infinity almost surely. 相似文献
76.
ShiYanYANG ZeMinXIE ChunJuanLIU LiHuaLIU WeiGAO 《中国化学快报》2002,13(12):1225-1226
A new kind of polyorganozircosilazane as Si/Zr/C/N-based ceramic precursor was synthesized from the condensation reaction of hexamethyleyclotrisilazane lithium salts(D3^NLi)and zirconium tetrachloride(ZrCl4).In the presence of N,N,N’,N’-tetramethyl ethylene diamine(TMEDA),polyorganozircosilazane was obtained in high yield. 相似文献
77.
聚合物电致发光材料研究进展 总被引:5,自引:0,他引:5
本文较详细地综述了聚合物电致发光材料的研究进展,重点介绍了聚对苯撑乙烯(PPV),并提出了有关聚合物电致发光材料及器件构造研究的一些观点。 相似文献
78.
微波常压法合成水杨酸酯 总被引:15,自引:0,他引:15
在浓硫酸催化下,采用微波常压法由水杨酸分别与正丁醇、异丁醇、正戊醇和异戊醇反应合成相应的水杨酸酯。结果表明:当水杨酸:醇:H2SO4=1:5.5:0.3(摩尔比)时,采用560W微波辐射22min,水杨酸酯的产率可达88.7% ̄96.4%,反应速度至少是常规反应的14倍。 相似文献
79.
Ionic liquids are a new kind of room-temperature molten organic salts. It can be used as solvents in the organic/polymeric syntheses, and some of them are called "green" solvents because of its recyclability1. Ionic liquids possess the superior properties, such as thermal stability up to 200(C, involatility and re-designability(for both cation and anion). The ionic liquid employed in this work is [bmim] [PF6]- ( butylmethylimidazolium hexafluorophosphate ) which is immiscible with water and h… 相似文献
80.
Seven transition metal molybdovanadoarsenic heteropoly compounds have been synthesized and characterized using IR, UV, TG-DTA, pH potential titration techniques. The molecular formulae of these compounds are pro-posed to be HxMyAsMO10V2O40·zH2O(x=1~3, y=1,2, M=Cr, Mn, Fe, Co, Ni, Cu, Zn).They are all keggin structure. Surface nature of these compounds have been investigated by temperature programmed desorption and temperature programmed reduction techniques. NH3-TPD results show that in TPD profiles of the compounds there are two desorption peaks corresponding to weak acid sites of desorption, respectively. Desorbing activativon energy and preexponential factor of weak acid site of desorption for compounds have been calculated. H2-TPR re-sults show that introducting transtion metal to molybdovanarsenic acid, the reduction peak temperatures of H2-TPR shift regularly with increasing d electron numbers of transition metals. In addition, Zn and Cu heteropoly com-pounds have yet apparent effect of hydrogen spill over. 相似文献