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131.
<正>SnO_2 nanorods were deposited on the Si substrates in an aqueous solution containing both SnCl_4 and CO(NH_2)_2.It is found that different self-assembled patterns of SnO_2 nanorods can be obtained by changing the deposition conditions such as the molar ratio of CO(NH_2)_2 to SnCl_4 and the pretreatment of the substrate.Scattered SnO_2 nanorods,for example,can be changed into flower-like patterns when the molar ratio of CO(NH_2)_2 to SnCl_4 is raised,and well-aligned nanorod arrays can be formed when the pretreatment of the substrate is changed.In addition,some interesting patterns,e.g.tree-like patterns,can also be observed.  相似文献   
132.
采用实时红外光谱仪(RT-FTIR)研究了单体结构、单体配比以及活性稀释剂结构对樟脑醌(CQ)/胡椒环(BDO)引发的光聚合动力学的影响,结果发现,UDMA虽然黏度较低,但是易发生链转移反应且在聚合体系中含量较高(70 wt%),可作为氢给体猝灭激发态CQ,从而影响CQ和BDO之间的相互作用.Bis-GMA虽然黏度大,但是反应活性高,当其与少量具有给氢能力的活性稀释剂TEGDMA配合使用时,不仅对聚合体系的反应活性影响较小,而且可显著降低体系的黏度,大大提高自由基的活动能力,有利于改善CQ/BDO的引发活性.  相似文献   
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Characteristic integrals of Toda field theories associated to general simple Lie algebras are constructed using systematic techniques, and complete mathematical proofs are provided. Plenty of examples illustrating the results are presented in explicit forms.  相似文献   
135.
Photopolymerization is extensively used in today's industrial field due to its advantages of rapid reaction, environmental friendly, energy saving and economical. Benzophenone is a most common photoinitiator (PI) using in photopolymerization because of its superior ability to initiate acrylate monomers. However, the intrinsic nature of initiator molecules is that they migrate out of polymer network, which limits its application, especially in the domain of food packaging materials. A polymerizable PI 4‐methylbenzophenone acrylate (MBPAc) was synthesized by a facile procedure and characterized by 1H NMR, 13C NMR, and MS analyses. A systematic study of the photopolymerization kinetics of MBPAc was explored by the Real‐Time Fourier Transform Infrared Spectrometer. The results show that the final conversion and photopolymerization rate of acrylate monomers are closely related to the factors of their chemical structure, viscosity, functionality and light intensity, which means MBPAc is an efficient PI. Ultraviolet‐visible Spectrophotometer and vitro cytotoxicity measurement results indicate that the noncytotoxic MBPAc shows significantly lower migration than its analogue. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 313–320  相似文献   
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Laser lift-off (LLO) technology is successfully used to prepare GaN-based TEM cross-sectional specimens. Detailed procedures of the method to prepare the specimens are demonstrated. Large thin areas suitable for TEM analysis were obtained. TEM images of the resulting GaN interface are studied, and the changes in structural quality are confined to approximately the first 250 nm of the epilayer. Clear TEM images of the whole epilayer and the InGaN quantum wells and the HRTEM images of the superlattice layer are demonstrated, showing that LLO is a quick and ideal method to study the crystal structure of the epilayer, especially if only the upper layers are of interest.  相似文献   
139.
Recent results of the characterisation of the structure, morphology and orientation of fine-scale, strengthening precipitate phases in selected magnesium alloys using transmission electron microscopy and microdiffraction are reviewed. The strengthening precipitate phases in Mg–Y–Nd alloys, aged to maximum hardness at 250°C, have been found to include two metastable precipitate phases β′ and β1, and the equilibrium precipitate β. The β′ phase has a globular form, a base-centred orthorhombic structure (potential point group of mmm), and an orientation relationship such that (100)β′//(1 10)α, [001]β′//[0001]α. The β1 phase has an f.c.c. structure (space group and an orientation relationship that may be described by (100)β1//[0001]α, and forms as plates parallel to The β phase has an f.c.c. structure (space group ) and also forms as plates on with an orientation relationship with the matrix phase that is identical to that observed for β1 phase. Precipitates in Mg–Al alloys, aged isothermally at 200°C, invariably have the b.c.c. structure of the equilibrium precipitate phase β (Mg17Al12). Three orientation relationships have been observed between β and the matrix phase. Most precipitates have an irrational orientation relationship that approximates to the Burger's relationship, (001)β//(0001)α, and a faceted lath morphology with habit plane parallel to (0001)α. A minor fraction of precipitates posses an orientation relationship that is of the form
and have a prismatic rod morphology. The long axes of these rods are parallel to [0001]α, and their faceted surfaces are parallel to A few precipitates are observed to have an orientation relationship such that
and a rod shape, with their long axes apparently inclined with respect to [0001]α.  相似文献   
140.
Based on the scattering-matrix method, the influence of obstacles on the thermal conductance in quantum wire was investigated. Three types of obstacles are employed in our calculation. We present a detailed study of the thermal conductance as a function of distance between two obstacles and temperature. The results show that there is qualitative difference in the dependence of the thermal conductance versus width between two obstacles for different temperatures. We also find that the calculated thermal conductance increases with the width W of quantum wire in all cases.  相似文献   
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