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含丙磺舒高分子药物纳米微球的制备 总被引:1,自引:0,他引:1
非甾体抗炎药丙磺舒与甲基丙烯酸 2 羟乙酯 (HEMA)反应制得含丙磺舒单体HP ,此单体在乙醇 /水体系中与甲基丙烯酸甲酯 (MMA)共聚得到含丙磺舒高分子药物纳米微球 ,聚合产物用1H NMR ,FTIR ,GPC和TEM进行了表征。结果表明HP中丙磺舒以酯键连接到甲基丙烯酸 2 羟乙酯上 ,微球由HP和MMA的共聚物构成 ,平均直径为 ( 90± 5 )nm ,含丙磺舒 4 7 4 % ,含药量较高。 相似文献
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铅纳米微粒用作油性润滑的摩擦学性能研究 总被引:4,自引:0,他引:4
在石蜡油 聚乙二醇的混合溶剂中 ,通过液相分散法成功地制备出了铅纳米微粒 .其中 ,石蜡油是反应介质 ,聚乙二醇是抗氧化剂 .同时 ,对铅纳米微粒的形貌和结构进行了透射电镜 (TEM)和X光衍射 (XRD)表征 .结果表明 ,铅纳米微粒呈球形 ,平均粒径为 70nm ,具有与本体铅相同的晶体结构 .另外 ,在四球试验机上表征了铅纳米微粒作为润滑油添加剂的摩擦学性能 .摩擦试验表明 ,铅纳米微粒具有良好的减摩抗磨性能 ,并能够显著改善基础油的承载能力 .磨斑表面分析表明 ,铅纳米微粒的抗磨减摩机制不是形成金属沉积膜 ,可能是在摩擦接触面形成滑动 轴承系 相似文献
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采用水热合成法和Stber法制备了氨基功能化SiO2包覆的Fe3O4磁性纳米微球Fe3O4@SiO2-NH2,它与巯基乙酸修饰的CdTe量子点通过酰胺缩合反应,将量子点键合到磁性微球上,制备出单分散性的Fe3O4@SiO2@CdTe磁性荧光双功能微球.用透射电子显微镜、X-射线衍射仪、荧光分光光度计、振动样品磁强计表征了该纳米复合微球的结构和性能.结果表明:Fe3O4@SiO2@CdTe磁性荧光复合微球单分散性好,平均粒径为470nm,饱和磁化强度为37.9emu/g,具有良好的超顺磁性和较高的荧光发光效率. 相似文献
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以改性聚苯乙烯微球为模板,采用化学镀法在聚苯乙烯微球表面包覆一层银,在四氢呋喃溶液中将聚苯乙烯微球溶解,得到中空Ag纳米球壳。采用扫描电镜、透射电镜和X射线衍射仪对样品进行了表征及分析,并用紫外可见分光光度计研究了粒子的光学性质。实验结果表明:运用此法成功地制备出中空Ag纳米球壳的内径为250 nm,壁厚约为15 nm,并且成功地使纳米粒子的紫外吸收光谱由600 nm红移至900 nm左右,实现了在可见光至近红外光区调节Ag纳米结构的吸收峰。 相似文献
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Knudsen effusion mass spectrometry (KEMS) was used for direct determination of lead oxide activity as a function of temperature in various regions of the PbO-ZrO(2)-TiO(2) system. From the results, the enthalpy, Gibbs free energy and entropy of formation of PbTiO(3) (PT), PbZrO(3) (PZ) and Pb(Zr,Ti)O(3) (PZT) were evaluated. In addition, the single phase widths of Pb(Zr(0.5)Ti(0.5))O(3) and PbTiO(3) perovskite structures were determined at 1100 K. The reaction rate of PZT synthesis in vacuo was followed by direct measurement of the change of PbO activity with time. Lead oxide activity in stoichiometric Pb(Zr(0.5)Ti(0.5))O(3), PbTiO(3) and Pb(0.968)(Zr(0.5)Ti(0.5))O(2.968) (3% lead deficient) at 850 degrees C was found to be 0.40, 0.45 and 0.1, respectively. PZT, PT and PZ powder samples prepared by a solid state procedure were also measured, all revealing lead deficiency. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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Chufeng Sun Ming Zhang Feng Zhou Ping Gao Yanqiu Xia Weimin Liu 《Journal of Macromolecular Science: Physics》2013,52(5):1006-1017
Multiply-alkylated cyclopentanes (MACs) composite thin films containing Cu nanoparticles are fabricated on the octadecyltrichlorosilane (OTS)-modified substrate by a spin-coating technique. The thickness, wetting behavior, and nanoscale morphologies of the films are characterized by means of ellipsometry, contact angle measurement, and atomic force microscope (AFM). The friction and wear behaviors of the thin films sliding against Si3N4 ball are examined on a UMT-2MT tribometer in a ball-on-disk contact mode. The worn surfaces of the OTS-MAC-Cu composite film and the counterpart Si3N4 balls are investigated with a scanning electron microscope. Water contact angle on OTS-MAC-Cu composite film is higher than that of OTS-MAC film. OTS-MAC-Cu composite film exhibits higher load-carrying capacity and better friction reduction and antiwear behavior as compared with OTS-MAC film. This may be attributed to the load-carrying and self-repairing property of the Cu nanoparticles in the composite film and the formation of a transfer layer composed of OTS, MAC, and Cu on the rubbing surface of the counterpart ball. 相似文献
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Junqing He Ling Zhang Chunzhong Li Biao Yan Renjian Tang 《Journal of Macromolecular Science: Physics》2013,52(10):2023-2033
The effects of copper and polytetrafluoroethylene (PTFE) on thermal conductivity and tribological behavior of polyoxymethylene (POM) composites were investigated by a hot disk thermal analyzer and an M-2000 friction and abrasion testing machine. The results indicated that the incorporation of 3 wt% copper particles into POM had little effect on the thermal conductivity of POM composites, but led to the decreased friction coefficient and wear rate of composites. As the copper content was increased, the thermal conductivity increased and reached 0.477 W m?1 K?1 for POM-25% Cu composite, an increase of 35.9% compared with that of unfilled POM, while the friction coefficient and wear rate of composites also increased. The incorporation of PTFE into POM-Cu composites had a negligible effect on the thermal conductivity of composites, but helped in the formation of a continuous and uniform transfer film and resulted in the reduction in the friction coefficient and wear rate of composites. The POM-15% Cu-10% PTFE composite, with a value of wear rate similar to unfilled POM possessed higher thermal conductivity and lower friction coefficient. 相似文献
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The thermodynamics and kinetics of phase separation in partially miscible blends of poly (vinyl methyl ether) (PVME) and two kinds of polystyrene (PS) with the same weight average molecular weight but different polydispersity were studied. The miscibility of PS/PVME with the monodisperse PS was better than that of PS/PVME with the polydisperse PS. Different morphology was observed for the two kinds of PS/PVME (10/90) blends during the nonisothermal phase separation process. The blend with monodisperse PS presented a co-continuous structure while the blend with polydisperse PS presented a viscoelastic phase separated network structure at a quench depth of 29°C. With increase of the heating rate, the increase of cloud point of PS/PVME (30/70) with polydisperse PS was smaller than that of PS/PVME (30/70) with monodisperse PS. During the isothermal phase separation of the critical composition (20/80) of PS/PVME with a quench depth of 30°C, it was found that the phase morphology of the two kinds of blends was nearly the same at the early stage of phase separation. However, as the dispersed phase, an approximately spherical droplet structure was observed in the blend with monodisperse PS at the late stage of phase separation, which did not appear in the blend with polydisperse PS. 相似文献
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Claudio A. Téllez S. Sergio G. de la Riva Eduardo Hollauer Ionel Haiduc Cristian S. Silvestru 《光谱学快报》2013,46(7):1469-1483
Abstract The infrared and Raman spectra of dimethyldithiophosphinate anion (CH3)2PS2 were measured and the vibrational modes for the anion complex were assigned. A Normal Coordinate Analysis in the Modified General Valence Force Field (MGVFF) approximation was carried out assuming C2v symmetry. Ab Initio Calculations at RHF and MP2 level were also carried out for the anion geometry as well as for its frequencies, intensities and force constants. 相似文献
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Limin Su Liming Tao Tingmei Wang Qihua Wang 《Journal of Macromolecular Science: Physics》2013,52(11):2222-2231
In this study a series of polyimide (PI) films were synthesized from fluorinated and nonfluorinated monomers which contained diamines and dianhydrides. The influence of fluorine-containing groups on the glass transition temperature (T g) and tribological properties of the PI films was investigated. The wear mechanism for the different kinds of PI polymers was comparatively discussed. T g was characterized by dynamic mechanical analysis and the tribological changes were evaluated by friction and wear tests as well as scanning electron microscopy (SEM) analysis of the worn surfaces. Fourier transform infrared (FTIR) has been used to study the structures of the PI polymers. Experimental results indicated that the fluorine groups influenced the thermal behavior (T g) of the PI films. Nonfluorinated PI films have lower friction coefficient and wear rate compared with the fluorinated ones. It was also found that the tribological properties of the PI films were closely related with the applied load. The friction coefficients and wear rates reduced with increasing the applied load. 相似文献
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Thermal and dielectric loss properties of Na2O-Bi2O3-TiO2-P2O5 phosphate glasses, have been studied by the differential scanning calorimetry (DSC) and electrical factor loss (tgi) measurements. The variation of tgi has been followed along two lines inside the quaternary systems Na2O-Bi2O3-5TiO2-P2O5 and Na2O-5Bi2O3-TiO2-P2O5. Experiments have been carried out from ambient temperature to 450°C and show a strong influence of sodium, bismuth and titanium ions on Tg and tgi. 相似文献
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2(8-羟基喹啉)-2(苯酚)合锆薄膜的制备与性能研究 总被引:5,自引:2,他引:5
设计合成了一种新型的有机电致发光材料2(8-羟基喹啉)-2(苯酚)合锆(Zr(OPh)2q2),制备了Zr(OPh)2q2薄膜,并利用红外光谱、差热-热重谱、扫描电镜、X射线衍射谱、UV吸收谱和荧光光谱等方法研究了其晶态、热稳定性、能带结构以及光致发光机理。结果表明,Zr(OPh)2q2的熔点为381.2 ℃,分解温度为467.1 ℃,具有非常高的热稳定性,利用真空热蒸镀方法很容易在经过净化处理的玻璃基底上形成高质量、无定形纳米级薄膜,在390 nm紫外光的激发下,Zr(OPh)2q2薄膜产生发光峰为525 nm、半峰宽度为107.6 nm的强黄绿色荧光,其粉体产生强黄色荧光,是一种性能优良的电致发光材料。 相似文献
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采用截断本征方程的方法研究2+1维SU(2)格点规范场的胶球质量及胶球波函数.计算结果表明五阶胶球质量△m/e 相似文献