Turbulent effect of SF6 thermal plasmas inside a puffer-assisted self-blast chamber

In this study, we calculated the whole arcing history of SF₆ thermal plasmas happened inside a puffer-assisted self-blast chamber during the alternative current interruption process with two different turbulence models. It is very difficult to correctly realize all phenomena happened inside the interrupter using the computational schemes; therefore, we have been trying to simplify the physics related in the problem. Because most flows encountered in the process are turbulent, the ability to predict turbulence for this application is invaluable for the engineer to design the chamber reliably. The objective of this paper is to model turbulence by averaging the unsteadiness of the turbulence, which are called Reynolds averaged Navier-Stokes models, and to compare the results with pressure and temperature field distributions during the whole arcing history. It was found that the two-equation turbulent model predicts bigger mixing of momentum, heat and species on the arc discharge of this interrupter than the zero-equation model does.     

Green chemistry: microwave-assisted facile synthesis of 6-imino-1,3,4-thiadiazenes from reaction of thiocarbohydrazones with malononitrile dimer

The reactions of thiocarbohydrazones with malononitrile dimer under microwave irradiation are reported. These reactions give 6-imino-1,3,4-thiadiazines in good yields. The structures of products were elucidated by MS, IR and NMR spectra together with elemental analyses. The reaction mechanism was discussed.     

电感耦合等离子体原子发射光谱(ICP-AES)法测定TB6钛合金中的Al和V

建立了电感耦合等离子体原子发射光谱(ICP-AES)法快速测定TB6钛合金中Al、V的方法。对试样溶解酸浓度、元素分析谱线的选择、样品基体与待测元素间的干扰等因素进行了研究。结果表明,Al、V元素的加标回收率分别为97.5%~100%、98.4%~102%,相对标准偏差(RSD)分别为1.2%、0.45%,可用于TB6钛合金中Al、V含量的实际测定。     

Simplified structure of the condensed phase of fire retarded PA6 nanocomposites in TGA as related flammability

This paper concerns with the analysis of the nature of the mass residue of PA6 and its nanocomposites in nitrogen. To assess the structure of the condensed phase during pyrolysis, this study presents thermal (by TGA in nitrogen) and condensed phase analysis of the residue (by FTIR-ATR) of PA6 nanocomposites consisting of phosphorous based flame retardants (FR) and/or nanoparticles (based on modified Montmorillonite clay). The thermal analysis reveals that the nanoparticles do not change the pyrolysis kinetics of PA6 whereas the FR does. The FR and NC used in the polymer nanocomposites (PNC) are capable of changing the structure of the char compared with pure PA6, where the char structure consists of polycyclic aromatic hydrocarbons (PAH) whereas the PA6 does not leave any considerable amount of mass residue. This residue analysis for decomposition samples in TGA in Nitrogen of the PA6/FR/NC composites complements previously published work for gas phase analysis ( FTIR-gas) as well as cone calorimeter characterization for their flammability. The overall aim, addressed here also, is to find out to what extent microscale measurements (e.g. TGA/FTIR/DSC/ATR) can be used a priori to delineate the flammability of polymer fire retarded composites. It is shown that FTIR-gas and FTIR (ATR) residue can be used to determine the fire retardant action (solid and/or gaseous) only qualitatively.     

Spiritual struggle related to plasma interleukin-6 prior to cardiac surgery.

Spiritual struggle appeared consistently to predict poor health outcomes, including mortality. Despite surging interest in the health benefits of religion and spirituality, the health hassle of existential conflicts and proinflammatory cytokines as a potential physiological mechanism has been overlooked. Based on psychological and theological assumptions, we argue for the universal nature of spiritual struggle, a crisis-related existential conflict, and for investigating its physiological influence as essential to understanding human nature. Increased levels of inflammatory cytokines such as interleukin-6 (IL-6) have been linked with adverse health outcomes and negative emotions. This study thus examined spiritual struggle related to plasma IL-6 in 235 adult patients undergoing cardiac surgery, along with positive religious coping, general coping, and optimism, controlling for standardized clinical medical indicators. Multiple regression analysis, following a preplanned sequence, showed that spiritual struggle (p = .011), behavioral coping (p = .013) were positively associated with excess plasma IL-6, controlling for medical correlates (e.g., left ventricular ejection fraction). We conclude that spiritual struggle, indicating the crisis in an existential relation, and behavioral coping strategies are associated with elevated pre-operative plasma IL-6. The interdisciplinary implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

6-丙基-2-萘酚的合成研究

以2-萘酚为起始原料,经过O-甲基化、酰化、黄鸣龙还原、脱甲基等一系列反应,得到目标产物6-丙基-2-萘酚,总收率为52.3%。其结构经IR、1H NMR、MS分析确证。     

光电隔离SPI接口冲击分压器

冲击电压试验是电气设备尤其是电力设备必不可少的绝缘试验项目,冲击电压的测量方法有很多,冲击分压器是其中比较常见的一种。冲击分压器是否可靠关系到电力系统的安全与正常工作。同时,冲击分压器也在电机定子电气性能检验中有所应用,用于电机定子匝间绝缘项目的冲击电压峰值和波前时间的测量。本设计根据需要选定符合标准且具有经济性的数字电位器和光耦元件,设计出具有光电隔离SPI接口的冲击分压器。     

中温沥青密封承插口在6m焦炉的应用

介绍了上升管承插口采用中温沥青密封处理的新方法,已成功应用于4座6m焦炉,全年效益可达33万元,改善了作业环境,经济环保效益显著。     

The role of niobium in MCM-41 supported with Pt and Au—A comparative study of physicochemical and catalytic properties

This paper reviews a series of results, partly published recently, on niobosilicate mesoporous molecular sieves of MCM-41 type modified with noble metals (Pt, Au). Platinum is introduced to MCM-41 by impregnation technique, whereas gold is incorporated by two methods: during the synthesis by co-precipitation (COP) and by impregnation (IMP). Three fundamental features of the prepared materials have been considered: (i) texture/structure, (ii) noble metal state and dispersion, and (iii) catalytic activity. The latter has been tested in selective reduction of NO by propene, methanol oxidation and WGS process. The role of niobium, as well as the effect of the nature of noble metals and the preparation method on the physicochemical and catalytic properties of the final materials based on NbMCM-41 (in comparison with siliceous MCM-41) is demonstrated.     

Microstructure analyses and volume fraction model of 3D 6-directional variable cross-sectional cone-shaped tubular braided fabric

The three-dimensional 6-directional variable cross-sectional cone-shaped tubular braided fabric (6DCTBF) has been applied successfully as the components in aerospace craft. The application of cone-shaped tubular braided fabric requires the densification of a small end to ensure ablation uniformity during composite fabrication. In this paper, in order to meet the size and performance requirements for 6DCTBF, a unique yarn-thinning technique used in the braiding process has developed and explained in detail by first analyzing the fiber bundle movement and distribution in modeling. After the yarn has been thinned, different zones are divided according to the constituting method of the yarn in its unit cell. Geometric models are built for different zones to determine the geometrical dimensions and volume fraction variation range. It has been shown that the theoretical model can accurately describe the 6DCTBF and provide a theoretical basis for the design of its structure and properties.