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991.
The radiation of fullerene molecules from the intersection area of the C60 beam with an electron beam with an energy of 27≤E
e
/eV≤100 was studied experimentally under conditions of a single collision. It was found that ionized C60
+* molecules make the main contribution to the radiation. The radiation intensity and the temperature of C60
+* as functions of the energyE
e
were measured. The kinetics of the radiation cooling of C60
+* was studied and the rate of the radiation loss of the ion energy (5.5·105 eV s−1) was determined at a temperature of 3150 K. For the heat model of radiation at the wavelength λ=540 nm, this corresponds
to the emissivity ε=1.1·10−2.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 273–276, February, 2000. 相似文献
992.
Domenico Acierno Eugenio Amendola Cosimo Carfagna Luigi Nicolais Rossella Nobile 《Molecular Crystals and Liquid Crystals》2013,570(1):553-562
In this work the effect of the inclusion of low percentages of theliquid crystal polymer PET/PHBGO on the rheological and mechanical behaviour of Polycarbonate is described. 相似文献
993.
ICP-AES用于茶油中多种无机元素的测定研究 总被引:4,自引:0,他引:4
采用电感耦合等离子发射光谱法(ICP-AES)对毛茶油以及精炼工艺各阶段茶油中的Ca,K,Mg,Cu,Cr,Zn,Sr等18种无机元素进行了分析测定。该方法的加标回收率为82.7%~112.5%,相对标准偏差0.00%~6.66%,18种元素的方法检测限在0.4~10 μg·L-1之间。结果表明:茶油中富含多种人体所必需的无机元素。随着精炼程度的增加,多数元素含量呈下降趋势。经过脱胶后茶油中的P, Ca, Mg含量显著下降;经过脱酸和脱色工艺后,能促进油脂自动氧化的Fe, Cu, Mn, Ni等金属元素的含量明显减少;Pb经过脱胶、脱酸工艺后未检出;Co和Cd无论是在毛茶油还是精炼茶油中均未检出。经过精炼的茶油能有效地去除过量的金属元素,含量能够达到国家卫生限量标准。同时实验表明采用ICP-AES法测定茶油中的多种无机元素具有简单、快速、准确度高等特点。 相似文献
994.
在无机SiO2纳米粒子存在下的苯丙乳液共聚合 总被引:18,自引:0,他引:18
研究了在无机SiO2纳米粒子存在下的苯丙乳液共聚合.选择了能使苯丙乳液稳定存在的乳化剂体系,研究了温度和SiO2的加入对聚合过程转化率的影响,结果表明,SiO2的加入对聚合过程有阻聚作用,使单体的转化率降低.SEM照片证明SiO2粒子已经进入苯丙乳液粒子中,而且SiO2的加入对乳液制成的膜断面形态有一定影响.实验发现在无机SiO2纳米粒子存在下,苯丙乳液共聚合时有较多残渣出现,对此通过改进乳液聚合进行了有效地改善.同时对制成的复合材料进行了力学性能和热学性能的测定. 相似文献
995.
使用532nm,8ns激光脉冲研究了两种新型的基于富勒烯C60结构体系的金纳米粒子合成物的光学非线性.Z-scan实验结果和理论分析的比较表明,材料的非线性吸收强烈地依赖于材料中的配合体,而非线性折射主要来自金纳米粒子的贡献.而且与熟知的C60甲苯溶液光限幅特性作了比较,分析了光限幅机理.
关键词:
60结构体系')" href="#">基于富勒烯C60结构体系
金纳米粒子
等离子体
光限幅 相似文献
996.
The family of fullerene molecules is composed of a large variety of compounds that have been synthesized following the discovery of C60 in 1985. The chemistry of fullerenes, developed in these last years, has allowed designing the properties of this family of molecules for specific applications in materials science. One of the main tasks to build up solid state devices based on fullerenes is the synthesis of materials doped with a highly dispersed and homogeneous distribution of fullerenes. Many of the peculiar photophysical properties, such as the reverse saturable absorption used to obtain a solid state optical limiter, are in fact lost in the aggregates of fullerenes. Sol-gel processing allows preparing inorganic oxides and hybrid organic-inorganic materials at low temperatures and presents an interesting alternative to organic polymers to entrap molecules of the fullerene family in a solid matrix. Porous inorganic solids and aerogels are also important classes of materials that can be synthesized via sol-gel and can act as hosts of fullerenes. In the present article we have reviewed the main achievements of sol-gel processing of fullerene based nanocomposite materials. 相似文献
997.
Junlin Yang Hongzhen Lin Shu Wang Yuliang Li Fenglian Bai Daoben Zhu 《Journal of polymer science. Part A, Polymer chemistry》2001,39(22):3981-3988
The fact that C60 is a good acceptor has stimulated interest in covalently linked complexes, including polymers and oligomers. Photoinduced charge transfer in these systems has great potential for use in photovoltaic devices. In this study, an alternating conjugated oligomer of alkylated carbazole and dialkoxyl‐substituted phenylene, with pendant C60 moieties, (PPV‐AFCAR) was prepared and characterized. The excited‐state properties of PPV–AFCAR were investigated with steady‐state spectroscopy and lifetime measurements. After photoexcitation, photoinduced energy transfer from the oligomer chain to the pendant moiety occurred in great proportion, but a charge‐separation process did not. Whether the energy‐transfer process was measurable or not depended on the system temperature. At 77 K, a quantum yield of more than 50% for energy transfer was found by the fitting of a linear combination of the excitation spectra of the precursor oligomer, the alternating conjugated oligomer of alkylated carbazole and dialkoxyl‐substituted phenylene PPV–ACAR, and the absorption spectra of C60. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3981–3988, 2001 相似文献
998.
Natural Sea Beauty系列化妆品富含来自Dead Sea水中的矿物质,对皮肤有较好的治疗和滋养作用.本文采用毛细管区带电泳的技术,电迁移双端进样,5 mmol/L咪唑-2 mmol/L硝酸为背景电解质,以富马酸调至pH 4.1,UV间接测定法(214nm),在6min内同时检测了化妆品中的阴阳离子(K+、Na+、Ca2+、Mg2+、Cl-、Br-),与离子色谱法所得结果进行了对照.此方法可为鉴别不同品牌的化妆品提供一定的依据. 相似文献
999.
以PdCl2,Cs2Se及Se为原料在乙二胺溶液中用有机溶剂热生长技术(SolvothermalTechnique)制备碱金属硒化物Cs2PdSe16,用单晶X射线衍射技术对其进行晶体结构分析.Cs2PdSe16属四方晶系,空间群为P4b2,晶胞参数为:a=1.2601(2)nm,b=1.2601(2)nm,c=0.7044(1)nm,V=1.1185(3)nm3,Z=2,R=0.0514,wR=0.0991.该晶体由相互交错的[CsPd(Se4)2]-层和[CsSe8]+层组成.热分析结果表明,其分解温度为334℃. 相似文献
1000.
The temperature dependence of retention of a wide range of inorganic anions is studied on two commercially available ion exchangers (Dionex AS11 and AS14 columns). Anion retention exhibited both exothermic and endothermic behavior, such that varying the temperature from ambient to 60°C produced selectivity changes. The anions displayed three groupings of temperature dependence: weakly retained singly charged anions (e.g., iodate, bromate, nitrite, bromide and nitrate); multiply charged anions (sulfate, oxalate, phosphate and thiosulfate); and strongly retained singly charged anions (iodide, thiocyanate and perchlorate). Temperature was ineffective at changing the selectivity of retention between anions of the same grouping. However, significant selectivity changes, including elution order reversal, could be achieved between anions from different groupings. 相似文献