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1.
分析了火炸药与武器信息化的关联性;论述了火炸药在武器装备发展中的综合地位与作用;提出作为武器信息化条件下火炸药发展策略和基本点的六项技术,即火炸药相关信息量的整合与准确表达、高能量与高安全性的统一、能量释放的可控制性、洁净燃烧与爆炸技术、燃烧爆炸的物理与化学作用延伸、非致命武器与化学战剂等.  相似文献   

2.
以山核桃、油茶和板栗3类果蓬为原料,研究了此类原料与杉木、松木屑在不同配比条件下对果蓬类致密成型特征及其机制炭质量的影响。证实了果蓬类原料因纤维素含量、木质素含量与杉木、松木存在差异,且因较高的灰分含量限制,需与杉木或松木屑等原料在一定配比条件下才可实现良好的致密成型。而配比选择试验结果则表明,果蓬原料与杉木、松木屑混合原料以3:7比例配料为宜;在此条件下,制备的机制炭外形平直无裂缝,得率为 33.85%~36.73%,固定碳含量 79.80%~86.20%,热值28.96~31.92 MJ/kg。  相似文献   

3.
Carbon aerogels were prepared by sol-gel polymerization of phenolic novolak and furfural followed by supercritical drying and pyrolysis. The porosity and morphologies of carbon aerogels were characterized by nitrogen adsorption, apparent density, He- pycnometer method, and transmission electronic microscopy (TEM). Effect of ratios of phenolic novolak to furfural (Ra) and total concentration of reactants (C) in sol-gel step on porosity and morphologies of carbon aerogels was investigated. The carbon aerogels synthesized are rich in meso- and macropores. The Ra determines the cross-linking density of polymers, thereby the compatibility of the polymers, and ultimately the shrinkage of gels in the drying and pyrolysis. The network sizes and the porosity of organic and carbon aerogels are mainly determined by Ra. The C has no effect on volume shrinkage of gels in drying and pyrolysis and has only dilute effect in determining bulk density of organic and carbon aerogels, and ultimately the porosity of carbon aerogels. Conversion of mesopores to micro- and macropores is observed, which is related to combination of C and Ra, and determines the partition of micro-, meso- and macropores.  相似文献   

4.
Fifty years with bile acids and steroids in health and disease   总被引:3,自引:0,他引:3  
Sjövall J 《Lipids》2004,39(8):703-722
Cholesterol and its metabolites, e.g., steroid hormones and bile acids, constitute a class of compounds of great biological importance. Their chemistry, biochemistry, and regulation in the body have been intensely studied for more than two centuries. The author has studied aspects of the biochemistry and clinical chemistry of steroids and bile acids for more than 50 years, and this paper, which is an extended version of the Schroepfer Medal Award lecture, reviews and discusses part of this work. Development and application of analytical methods based on chromatography and mass spectrometry (MS) have been a central part of many projects, aiming at detailed characterization and quantification of metabolic profiles of steroids and bile acids under different conditions. In present terminology, much of the work may be termed steroidomics and cholanoidomics. Topics discussed are bile acids in human bile and feces, bile acid production, bacterial dehydroxylation of bile acids and steroids during the enterohepatic circulation, profiles of steroid sulfates in plasma of humans and other primates, development of neutral and ion-exchanging lipophilic derivatives of Sephadex for sample preparation and group separation of steroid and bile acid conjugates, profiles of steroids and bile acids in human urine under different conditions, hydroxylation of bile acids in liver disease, effects of alcohol-induced redox changes on steroid synthesis and metabolism, alcohol-induced changes of bile acid biosynthesis, compartmentation of bile acid synthesis studied with 3H-labeled ethanol, formation and metabolism of sulfated metabolites of progesterone in human pregnancy, abnormal patterns of these in patients with intrahepatic cholestasis of pregnancy corrected by ursodeoxycholic acid, inherited and acquired defects of bile acid biosynthesis and their treatment, conjugation of bile acids and steroids with N-acetylglucosamine, sulfate-glucuronide double conjugates of hydroxycholesterols, extrahepatic 7alpha-hydroxylation and 3-dehydrogenation of hydroxycholesterols, and extrahepatic formation of C27 bile acids. The final part discusses analysis of free and sulfated steroids in brain tissue by capillary liquid chromatography-electrospray MS and suggests a need for reevaluation of the function of steroid sulfates in rat brain.  相似文献   

5.
简述了己烷油装置配套的储运系统现状,综述了低温冷凝法、活性炭吸附法、溶解吸收法、膜选择渗透法以及氧化燃烧法五种油气回收技术的原理,评价对比其中四种技术的尾气排放情况、二次污染情况、安全运行状态、设备工艺复杂程度等指标,根据各单一技术的优缺点,探讨了冷凝法和吸附法相结合、冷凝法和膜分离法相结合的两种较为实用的油气回收复迭技术,简述了其工作原理。对己烷油装置的储运系统提出改进建议,得出增上油气回收系统的可行性结论。  相似文献   

6.
从化学组成上区分宋代汝瓷与民窑钧瓷   总被引:7,自引:0,他引:7  
郭景康  黄瑞福 《陶瓷学报》1999,20(3):153-157
应用质子激发X荧光分析技术测定了一组宋代汝瓷和一组宋代民窑钧瓷瓷片的化学组成及浓度,对汝瓷与民窑钧瓷的主量,次量化学组成和痕量化学组成进行了比较,应用模式识别方法加以研究,得到了区分宋代汝瓷和民窑钧瓷的可视分类图和数学判据。  相似文献   

7.
杨志华  李斌 《化学与粘合》2006,28(4):257-260
PVC是一种应用广泛的高分子材料,但因其具有热稳定性差、易燃烧、发烟量大的缺点而限制了发展,因此PVC的阻燃与抑烟成为阻燃科学研究领域的关键问题之一。纳米型阻燃抑烟剂克服了传统型阻燃抑烟剂添加量大、阻燃抑烟效果不明显的缺点,为研究和解决PVC阻燃抑烟提供了一个新途径。本文介绍了PVC纳米阻燃抑烟剂的制备方法、表征手段及其在PVC中的应用以及PVC降解、阻燃与抑烟的表征,最后简要论述PVC阻燃抑烟的发展趋势。  相似文献   

8.
油气是重要的战略资源,关系国计民生。随着工业化和城镇化的加速推进以及汽车进入普及期,我国油气供需形势日趋严峻。解决我国油气供应不足的问题。应首先立足于开发利用国内的油气资源,不断提高自给水平,然而却存在管理体制和政策的掣肘。世界油气主产国都不断改善其油气资源开发利用的管理体制与政策,促进更加有效与合理地开发利用和保护油气资源。本文总结了该领域的国际经验,从加强油气资源法律法规体系建设、促进油气资源管理体制改革、完善油气资源矿业管理等方面提出了对我国的启示和改革建议。  相似文献   

9.
《云南化工》2018,(12):93-94
石油和天然气的储存和运输,即石油和天然气资源的储存和运输,是有效利用石油和天然气资源的重要先决条件。随着中国经济社会的快速发展和油气储运技术的更新和发展,油气储运业面临着重大机遇和挑战。针对油气储运技术发展现状,确定基于安全,环保,节能的油气储运技术要不断的创新,才能促进油气进一步发展。  相似文献   

10.
Isomerization of isopropylidene glycerol ketals and benzylidene glycerol acetals was studied, and isoraerization equilibria were established. Reaction of benzaldehyde with glycerol gave four benzylidene glycerol isomers, which were separated by column chromatography and characterized by NMR spectroscopy and other methods. Isomerization of 1- and 2-monoglycerides and of 1,2- and 1,3-diglycerides, and their separation by column chromatography, are described. Mechanisms of isomerization in mono- and diglycerides and factors which affect them are discussed. Isomerization of 1- and 2-glycerophosphates and of cyclic glycerophosphates by acid and base was also studied. Hydrolysis products of L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine were separated by column chromatography and characterized by periodic acid oxidation, optical rotation, and NMR spectroscopy. No isomerization of unhydrolyzed L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine was observed. Evidence indicated that acid-catalyzed hydrolyses of phosphoglycerides are under thermodynamic control whereas most base-catalyzed hydrolyses are under kinetic control.  相似文献   

11.
《云南化工》2019,(12):165-166
对目前油气储运技术中存在的安全问题进行深层次的探讨,根据引起这些问题的原因,提出相应的解决措施,为保障油气储运过程中的安全奠定基础。  相似文献   

12.
The results of an analysis of the current state of the Moscow Coal Basin and the development of science and technology for the multiple use and conversion of coal into refined energy carriers, products, and materials with new consumer properties are presented. It is demonstrated that a number of processes and facilities based on the coals and overburden rocks of the basin have been prepared for technical implementation, namely: the generation of heat and power at plants with in-cycle coal gasification; the fluidized-bed combustion of coal in low-power boiler units (50?C60 MW); the manufacture of ballast-free humic plant growth stimulators and coagulants for the purification of wastewater and drinking water; and the use of coals and coal mining and benefication wastes as catalytic additives in the process of hydrogenation.  相似文献   

13.
王素娟  裴月湖  孙秀燕 《农药》2004,43(8):348-350,345
阐述31种农药在3种电离方式:电子轰击质谱(EIMS)、正化学电离质谱(PCIMS)和负化学电离质谱(NCIMS)下的质谱特征和裂解规律,为农药残留的筛选和结构确证奠定基础。分别测定18种有机氯农药、13种有机磷农药的电子轰击质谱(EIMS),正化学电离质谱(PCIMS)和负化学电离质谱(NCIMS)。在EIMS中,有机氯农药主要产生[M—Cl]^ 、[M—HCl]^ 离子,有机磷农药主要产生磷酸基和磷酸酯基离子;在NCIMS中,[Cl]^-或[HCl2]^-离子是有机氯农药的基峰,有机磷农药主要产生磷酸酯基负离子,某些芳香硫代磷酸酯还可产生重排离子;而在PCIMS中.大多数农药的灵敏度较低.没有观察到质谱。  相似文献   

14.
高频电磁场抑垢效果的实验研究   总被引:3,自引:0,他引:3  
用高频电磁法进行换热设备的抑垢处理,具有应用方便、投资小、无污染等优点,是一种极具发展前景的应用技术。但有效评价高频电磁场在线抑垢效果的策略及手段还很欠缺。基于污垢热阻值的在线监测技术,通过自主研发的在线监测评价实验系统采集和处理模拟换热器中研究管段的流体出入口温度、流速和壁温,得到加磁处理与未加磁处理的污垢热阻变化趋势以及加磁处理的抑垢率。同时测量和分析了溶液电导率的变化,完成了高频电磁场的抑垢效果的客观评价,并取得了良好的预期结果。  相似文献   

15.
《云南化工》2019,(9):113-115
职业健康安全管理,是关系到石化企业安全发展和员工健康的大事。针对空分装置生产的特点,分析了影响员工职业健康的主要因素——噪声的产生根源,提出并实施了以防护为重点,监督管理为铺的职业健康管理模式,通过有效落实职业健康安全防护和监督管理,为空分装置岗位员工的职业健康保驾护航。  相似文献   

16.
The structure and properties of PET and PET fibres are examined on three structural levels — molecular, supermolecular, and micromolecular. It was shown that the unique properties of the fibres are determined by the aliphatic-aromatic structure of PET and the chemically regular molecular structure. The structural dependence of the fundamental physicomechanical and physicochemical properties of PET and PET fibres was analyzed. It was shown that the high glass transition temperature of PET and PET fibres is determined more by molecular rigidity than by intermolecular interactions and varies little under the effect of moisture. This causes high stability of the structure in mechanical effects and exposure to heat and moisture, high reversibility of deformation, and insignificant creep under mechanical stresses. The structure and fundamental properties of PET and PET fibres are compared with the characteristics of other kinds of large-tonnage fibre-forming polymers and fibres and other aliphatic-aromatic polyesters and fibres. The advantages of using polyester fibres for fabrication of household and industrial articles are substantiated and summarized based on an examination of the properties of these fibres.  相似文献   

17.
邻、对氯苯甲醛的传统生产工艺分别采用邻、对氯甲苯作为原料,然而邻、对氯甲苯沸点非常相近,分离困难。根据邻、对氯苯甲醛熔点差别大的特性,本文提出以混合邻、对氯甲苯为原料联产邻、对氯苯甲醛的新工艺路线,该工艺避免了混合邻、对氯甲苯的分离工艺,可以大大节省分离能耗。本文重点研究了采用相转移催化水解邻、对氯苄叉二氯混合物同时制备邻、对氯苯甲醛的工艺,考察了催化剂用量、水量及原料配比对反应的影响,确定了适宜的水解反应工艺条件,为以邻、对氯甲苯混合物作原料同时制备邻、对氯苯甲醛的联产工艺开发奠定基础。  相似文献   

18.
李师财  于泳  金祖权 《硅酸盐通报》2020,39(12):3743-3752
远海工程建设面临钢筋混凝土易腐蚀、河砂和淡水匮乏等难题。国内外学者选择资源丰富的海水海砂代替淡水河砂制备混凝土,并研究其工作性能、力学性能及耐久性能。海水海砂中高含量的氯盐会加快水泥水化和凝结,导致早凝和早期强度提高,但后期增长变缓,最终强度与淡水河砂混凝土相近。海砂中少量的贝壳对混凝土工作性能和力学性能影响不大。海水海砂混凝土中的氯离子传输及结合方式更为复杂,其不同于内掺型氯离子,由此导致海水海砂混凝土中的钢筋锈蚀机理改变。辅助胶凝材料、复合型阻锈剂及纤维增强复合筋等为海水海砂混凝土结构应用提供了保障。  相似文献   

19.
Measurements of the surface tension, density and viscosity of sodium dodecyl sulfate (SDS) and rhamnolipid (RL) mixtures were carried out in aqueous solution. From the obtained results, composition of mixed surface layer at the water–air interface, mixed micelles, parameter of intermolecular interactions, activity of SDS and RL in the surface layer and micelles, Gibbs standard free energy of adsorption and micellization as well as Gibbs free energy of SDS and RL mixing in the surface layer and micelles were established. These parameters were discussed in the light of independent adsorption of SDS and RL and the size of their molecules as well as the area in contact with water molecules. A correlation between the number of water molecules in contact with those of SDS and RL and standard free energy of adsorption as well as micellization of these surfactants was observed. A correlation between the apparent and partial molar volumes of RL and SDS in their mixture and size of surfactant molecules as well as the average distance between molecules was also found. The parameter of intermolecular interactions indicates that there is a synergetic effect in the reduction of water surface tension and micelle formation.  相似文献   

20.
碳酸乙烯酯和碳酸丙烯酯复合溶剂的工业脱碳性能研究   总被引:3,自引:0,他引:3  
谢阳  王纪孝  屈强好  吴一 《化肥工业》2000,27(1):43-44,48
在碳酸乙烯酯(乙碳)和碳酸丙烯酯(丙碳)复合溶剂脱除合成气CO2中试实验的基础上,就乙碳和丙碳的分子结构特点对乙碳和丙碳及两者复合溶剂的CO2吸收性能进行了比较,讨论了乙碳-两碳-水复合溶剂的相行为及其对工业操作的影响,并验证了乙碳-丙碳复合溶剂应用于工业的可行性及其特点。  相似文献   

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