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101.
研究了正在进行化学平衡的富重子夸克-胶子物质的双轻子产生,发现由于产生在RHIC能量 的化学非平衡的富重子夸克-胶子物质冷却慢和高的初始温度,导致中等质量双轻子产生重 大增强.因此,中等质量双轻子的增强可以是夸克-胶子物质形成的信号.同时,这个增强能 补偿由于初始夸克化学势增加引起的双轻子抑制,因而双轻子产额的抑制不再是夸克-胶子 物质产生的信号. 关键词: 化学非平衡夸克-胶子物质 热粲夸克 双轻子  相似文献   
102.
The reticulation process of an epoxy resin using an amine as a cure agent was studied at different temperatures and concentrations of the cure agent with dynamic mechanical thermal analysis. The study was performed under both isothermal and nonisothermal conditions, and a temperature–time–transformation diagram was obtained. The measurements from the two modes gave similar results, although the nonisothermal mode required fewer experiments. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1965–1977, 2003  相似文献   
103.
热喷涂技术的现状和发展   总被引:4,自引:0,他引:4  
介绍了热喷涂工艺的特点,喷涂方法的种类及其技术以及热喷涂技术的应用概况,并对热喷涂技术的发展方向给予了展望。  相似文献   
104.
Angra dos Reis/Itaguai region of the state of Rio de Janeiro, Brazil, is a very problematic area due to the instability of slope and landslides, due to geological and geomorphological conditions and to the significant and continuous human occupation over favorable areas is prone to the triggering of landslides. The samples were analyzed by thermogravimetry (TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA). This paper analyzes and characterizes the clay minerals and presence of water, gravitational mass movements’ sites and compares it with sites where gravitational mass movements do not occur. Indeed, this analysis also attempts to verify the presence of minerals.  相似文献   
105.
We have studied the spectral properties and morphology of thin films (TVD films) formed by thermal vacuum deposition of 4,4′-bis[(E)-1-(1,3-benzoxazol-2-yl)-2-ethenyl]-1,1′-biphenyl and its substituted derivatives. We have shown that introducing bulky 2,2′-oxyhexyl substituents into the biphenyl units leads to a shift of the fluorescence maximum for the TVD films toward shorter wavelengths, a decrease in their photostability, and aggregation of the films during storage. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 3, pp. 300–303, May–June, 2007.  相似文献   
106.
This paper presents applications of thermal analysis to observe the course of reduction of acidic pellets, metallurgical substances whose reducibility and strength are basic parameters of use in blast furnace processes. Both parameters depend on the mineral composition of the samples. The investigations included determination of the chemical and phase compositions of the initial samples and reduction products. Research was conducted on acidic pellets from Połtawa (Poland), applied in the T. Sendzimir Steelworks (Poland), in comparison with pellets from Brazil, Canada and Lebedyn (Russia). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
107.
108.
对加载到塑性阶段的矩形截面柱,本文研究了几何缺陷对屈曲的影响,在分析中考虑了弹性卸载的影响,求出了荷载、缺陷大小及分叉模态幅值之间的精确渐近关系式,结果表明在塑性阶段最大承载力对小缺陷非常敏感,但当缺陷大小达到某一值后,可能不存在最大载荷。  相似文献   
109.
Polycrystalline (1−x)Ta2O5xTiO2 thin films were formed on Si by metalorganic decomposition (MOD) and annealed at various temperatures. As-deposited films were in the amorphous state and were completely transformed to crystalline after annealing above 600 °C. During crystallization, a thin interfacial SiO2 layer was formed at the (1−x)Ta2O5xTiO2/Si interface. Thin films with 0.92Ta2O5–0.08TiO2 composition exhibited superior insulating properties. The measured dielectric constant and dissipation factor at 1 MHz were 9 and 0.015, respectively, for films annealed at 900 °C. The interface trap density was 2.5×1011 cm−2 eV−1, and flatband voltage was −0.38 V. A charge storage density of 22.8 fC/μm2 was obtained at an applied electric field of 3 MV/cm. The leakage current density was lower than 4×10−9 A/cm2 up to an applied electric field of 6 MV/cm.  相似文献   
110.
Dithiocarbamate functions were incorporated into different polyacrylamide matrices crosslinked with a flexible and hydrophilic crosslinking agent, tetraethyleneglycol diacrylate (TEGDA), and their complexation behaviours were investigated. Crosslinked polyacrylamides with varying extents of the tetrafunctional TEGDA crosslinks were prepared by free radical solution polymerization at 60°C using potassium persulphate as initiator in ethanol. The dithiocarbamate functionality was incorporated into these polyacrylamides by a two-step polymer-analogous reaction involving (i)trans-amidation with ethylenediamine and (ii) dithiocarbamylation of the aminopolyacrylamide with carbon disulphide and alkali. The complexations of dithiocarbamate with Cu(II), Ni(II), Zn(II), Co(II) and Hg(II) ions were followed under different conditions. The metal ion intake varied with the extent of the crosslinking agent and the observed trend in complexation is Hg(II) > Cu(II)> Zn(II)> Co(II)> Ni (II). The time-course of complexation, the possibility of recycling, swelling characteristics, and spectral and thermal analyses were carried out. The thermal stability increases upon complexation with metal ions.  相似文献   
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