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41.
介绍了环糊精和表面活性剂作为有序介质在室温磷光中的研究进展.并对各种方法的特点和应用情况作了简要概括。认为环糊精和表面活性剂混合介质能大大提高发光物质的室温磷光.而且操作简便.应用前景广阔。 相似文献
42.
基于Smtp和Pop3的邮件还原技术已经日臻成熟,而由于主要Webmail邮件格式不同,Webmail邮件还原技术一直是难点。通过对主要Webmail的内容格式分析,针对不同网站的Webmail建立相应的还原模块,实现对主要Webmail的内容还原。实验结果验证了该技术的有效性。 相似文献
43.
Jiuxin Jiang Bo Zhu Peiling Wang Weiwu Chen Dongsheng Yan Hanrui Zhuang Yibing Cheng 《Journal of the American Ceramic Society》2005,88(4):950-953
The Pr α-sialon powders prepared by self-propagating high-temperature synthesis (SHS), consisting of 55 wt% Pr α-sialon and 45 wt% of β-sialon (abbreviated as α' and β'), were hot-pressed at 1800°C for 1 h. The results showed that Pr α' phase would transfer to β' with the appearance of JEM phase (Pr(Si6− z Al z )(N10− z O z )) after sintering, thus resulting in the increase of β' phase to 86 wt%. The addition of Y2 O3 into SHS-ed Pr α' powders as the starting materials restrains the transformation of α' to β' and prevents the formation of JEM phase as well. The nucleation mechanism of Pr α' grain during hot-pressing was investigated in terms of transmission electron microscope and energy-dispersive spectrometer analysis. Two nucleation modes of Pr α' grains were found, i.e., nucleating on the undissolved Pr α' grains and on the nuclei of (Pr, Y) α' grains precipitated from liquid phase. 相似文献
44.
Ink‐eliminated sludge flour (IESF), waste residue from the recycling treatments of waste paper, was utilized as a new kind of filler to reinforce polypropylene (PP) in this research work. Different coupling agents, including maleated anhydride grafted PP (MAPP), stearic acid (SA), and titanate (NDZ‐101), were used to increase the compatibility between IESF and PP. By using different measurements, the microstructure, morphology, thermal behaviors, and mechanical properties of the IESF/PP composites were investigated in detail. It was found that IESF, as a nucleation agent, not only induced the crystallization orientation of PP but also accelerate the crystallization rate of PP. Just as indicated in the experiments, the presence of IESF has shown the advantages of increasing the dimensional stability, the hardness and the flexural property, and the presence of coupling agents has a favorable effect on the improvement of dimensional stability. Moreover, the coupling agent has minor influence on the mechanical property, even causes some decrease in the impact strength. Among these three coupling agents, MAPP is found to be the best coupling agent for increasing the interfacial adhesion between IESF and PP, and the MAPP addition makes the PP composite possess the quickest crystallization rate and greatest tensile strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 513–520, 2003 相似文献
45.
A metal ions (Ag, Bi, V, Mo) modified sol–gel method was used to prepare a mesoporous Ag0.01Bi0.85V0.54Mo0.45O4 catalytic membrane which was used in the selective oxidation of propane to acrolein. By optimizing the preparation parameters, a thin and perfect catalytically active membrane was successfully prepared. SEM results showed that the membrane thickness is 5 μm. XRD results revealed that Ag0.01Bi0.85V0.54Mo0.45O4 with a Scheelite structure, which is catalytically active for the selective oxidation of propane to acrolein, was formed in the catalytic membrane only when AgBiVMoO concentrations were higher than 40%. Catalytic reaction results demonstrated that the selective oxidation of propane could be controlled to a certain degree, such as to acrolein, in the catalytic membrane reactor (CMR) compared to the fixed bed reactor (FBR). For example, a selectivity of 54.85% for acrolein in the liquid phase was obtained in the CMR, while only 8.31% was achieved in the FBR. 相似文献
46.
Lijin Xie Junfeng Ma Jun Zhou Zhongqiang Zhao Hua Tian Yonggang Wang Jiantao Tao Xiaoyi Zhu 《Journal of the American Ceramic Society》2006,89(5):1717-1720
Well-crystallized bismuth tungstate (Bi2 WO6 ) powders with different morphologies were successfully synthesized via a low-temperature molten salt method. The powders were characterized by X-ray diffraction, transmission electron microscopy, and UV-Vis, respectively. It was found that the variation of morphology of the obtained Bi2 WO6 powder mainly depends on the different reaction temperatures and the weight ratio of LiNO3 –NaNO3 salt to precursor. In addition, the UV-Visible absorption spectra showed that the synthesized powders had strong light absorption properties not only in the ultraviolet light but also in the visible light region. 相似文献
47.
合成气中氨含量测定方法的改进 总被引:1,自引:0,他引:1
用快速测定仪测定气体中的氨含量,采气量为50ml,可准确测出高含量氨体积百分比含量为80%-100%和低含量氨体积百分比含量为1%-20%的样气,该仪器结构简单,易于制造,测定过程简单,结果准确,一目了然。 相似文献
48.
49.
朱云溪 《网络安全技术与应用》2014,(10):200-201
云计算是一种基于互联网的计算方式,通过这种方式,共享的软硬件资源和信息可以按需提供给计算机和其他设备,该技术是一种近些年来发展的新兴科技,同时在一定的程度之上遍布于软件企业的各个领域之中,引导着当前软件企业发展的方向.基于此,本文探讨了云计算背景之下软件企业创新的趋势. 相似文献
50.
Shape‐memory polyurethane/multiwalled carbon nanotube (SMP–MWNT) composites with various multiwalled carbon nanotube (MWNT) contents were synthesized, and the corresponding SMP–MWNT fibers were prepared by melt spinning. The influence of the MWNT content on the spinnability, fracture morphology, thermal and mechanical properties, and shape‐memory behavior of the shape‐memory polymer was studied. The spinning ability of SMP–MWNTs decreased significantly with increasing MWNT content. When the MWNT content reached 8.0 wt %, the fibers could not be produced because of the poor rheological properties of the composites. The melt‐blending, extrusion, and melt‐spinning processes for the shape‐memory fiber (SMF), particularly at low MWNT contents, caused the nanotubes to distribute homogeneously and preferentially align along the drawing direction of the SMF. The crystallization in the SMF was promoted at low MWNT contents because it acted as a nucleation agent. At high MWNT contents, however, the crystallization was hindered because the movement of the polyurethane chains was restricted. The homogeneously distributed and aligned MWNTs preserved the SMF with high tenacity and initial modulus. The recovery ratio and recovery force were also improved because the MWNTs helped to store the internal elastic energy during stretching and fixing. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献