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1.
二异丙基氟磷酸酯酶(DFPase EC3.1.8.2)是存在于微生物、动物及人体内的一类有机磷化合物水解酶,它分为鱿鱼型,Mazur型及OT型三种亚型,它们水解有机磷化合物中的亚磷酸酐键(P-F或P-CN键),酶粗制剂能有效预防小鼠、猪、豚鼠、猫、猴等有机磷化合物的中毒且长期存活无后遗效应,提示DFPase可作为环境污染及毒剂的解毒酶。  相似文献   

2.
对几种重要结构类型的含P-N键有机磷(膦)酸酯类生物活性物质的研究发展进行了综述,并对某些化合物作用机理进行了探讨。  相似文献   

3.
利用小分子模型化合物-磷酰化丝氨酸甲酯在不同体系中的各种反应来研究生物大分子胆碱酯酶的被抑制作用。结果表明,模型分子的基本反应与酶的抑制机制具有一定的类似性和相关性。为研究有机磷化合物对胆碱酯酶的抑制机理提供了更为简单的方法。  相似文献   

4.
赵国辉 《防化学报》1996,7(3):59-66
赵玉芬院士领导的生命有机磷化学实验室以磷化氨基酸为微型酶研究磷在生命化学中的作用。本文介绍了他们的研究成果:磷酰化对氨基酸及其成肽的影响,磷酰化在脱氧核糖核酸与核糖核酸生化作中的作用,以及磷酰化对糖类生化反应中的作用等。最后简要分析了这一理论对防化科技研究的启示。  相似文献   

5.
乙炔是一种无色略带醚味的气体,市售乙炔因含有PH_3、H_2S和NH_3等杂质而略带大蒜味。乙炔分子式为C_2H_2,结构式为HC≡CH,碳碳叁键中有一个σ键。两个‖键。乙炔化学性质活泼,溶点为-81.8℃。乙炔常用作焊接,切割的气源和制造氯乙炔、合成橡胶、丙烯酸酯等产品的化工原料,易爆炸,在储运中有着特殊的消防安全要求。  相似文献   

6.
液晶型化学传感器检测有机磷化合物的研究   总被引:3,自引:0,他引:3  
报道了一种检测有机磷化合物的液晶型化学传感器,对其作用机理进行了讨论,传感器响应的线性范围0.03~1.00g/m^3,线性方程y=0.145X 0.388,相关系数r=0.9962。  相似文献   

7.
自蔓延反应喷涂表面涂层技术进展   总被引:4,自引:0,他引:4  
围绕自蔓延反应喷涂技术与工艺研究和自蔓延反应喷涂相关理论研究两个方面,介绍了这一技术领域的发展状况。SHS反应喷涂技术将燃烧合成与传统热喷涂相融合,将各类高化学能的反应型粉材、线材引入喷涂技术中制备高性能陶瓷和金属间化合物涂层,发展了SHS反应药芯线材电弧喷涂、SHS等离子喷涂、爆炸反应喷涂以及SHS反应火焰喷涂等技术手段。一方面,对其中的配系设计、控制参数、涂层性能和相关设备等方面开展了深入的实验研究;另一方面,围绕涂层形成过程、喷涂条件下的反应机理与模式,以及反应喷涂过程中的能量状态和粒子的物理状态等方面开展了初步的理论研究,正在构筑较完整的理论体系。  相似文献   

8.
采用低分子量固态聚碳硅烷和乙酰丙酮铝为原料,利用Si-H与乙酰丙酮铝之间的交联反应合成适于熔融纺丝的聚铝碳硅烷。研究了反应条件对产物数均分子量、软化点和组成结构的影响及交联反应程度与可纺性之间的关系。实验结果表明:随着反应温度的升高和反应时间的延长,反应程度提高,残余乙酰丙酮基减少,Si-O-Al交联支化结构增多,分子量和软化点增大,可纺性随之下降。当乙酰丙酮铝投料比为8%时,在370℃下反应4~6 h,可得到软化点为206~221℃,Al wt%=0.68%,具有良好可纺性的聚铝碳硅烷。  相似文献   

9.
液态聚硅烷高温高压合成聚碳硅烷工艺研究   总被引:4,自引:2,他引:2       下载免费PDF全文
以聚二甲基硅烷裂解制备的液态聚硅烷(LPS)为原料,在高压釜内高温高压反应制备了聚碳硅烷(PCS)先驱体,研究了合成条件对反应终压、Si H键含量、产物产率、软化点、分子量分布及可纺性的影响。研究表明,随着反应温度的提高、反应时间的延长,反应终压逐渐增大,产物的分子量与软化点增高,但同时分子量的分散性增大,使可纺性变差。当LPS在高压釜内460℃下反应3~4h,或450℃下反应6~7h时,可以制得软化点约为210~230℃的PCS,其高分子部分含量约5wt%~10wt%,Si H键含量大于0.9,可纺性较好,适合于制备SiC纤维。  相似文献   

10.
磷系阻燃剂毒性小、低烟、价格较低,在阻燃剂开发领域中最引人注目。介绍了磷系阻燃剂的阻燃机理,无机和有机磷系阻燃剂在阻燃聚丙烯中的研究现状,并论述了磷系阻燃聚丙烯存在的问题及发展趋势。  相似文献   

11.
Chemical warfare agents (CWA) are stockpiled in large quantities across the globe. Agents stored in inaccessible facilities need to be destroyed rapidly without dispersing the compounds to surrounding areas. Metal-based energetic formulations are used in such prompt defeat applications to rapidly decompose the CWA by generating a high temperature environment. An alternate, and possibly a more effective decomposition pathway could be provided by chemicidal action of aerosolized condensed combustion products, which typically consist of metal oxides. Toxic fumes that escape the high tem-perature blast zone can be neutralized by smoke generated during combustion, depending on the par-ticle size, surface characteristics, chemical properties, and concentration of this smoke. This review considers relevant experimental and modeling studies quantifying decomposition of CWA comprising organophosphorus compounds and their surrogates on the surface of various metal oxides. Dimethyl methylphosphonate (DMMP), a sarine surrogate, was used most commonly for such experiments. Many reported efforts focused on the mechanisms of adsorption of DMMP to various metal oxides and initial reaction steps cleaving various bonds from the chemisorbed molecules. For selected oxides, these ex-periments were supported by quantum-mechanical calculations. In other studies, the capacity of oxide surfaces to adsorb and decompose DMMP was quantified. In most cases, porous catalysts were used although limited experimental data are available for aerosolized nonporous oxide particles. The reported experimental data applicable to scenarios involving prompt decomposition of CWA are summarized. It is noted that information is lacking describing respective heterogeneous reaction kinetics. Preliminary estimates of aerosolized smoke particle concentrations required to destroy CWA are made considering gas phase diffusion rates and reported values of the oxide capacity to decompose CWA or their surrogates.  相似文献   

12.
《防务技术》2020,16(2):374-380
Micro-TATB particles with different sizes and 3D nanoporous TATB architectures with different specific surface areas were prepared through recrystallization to study short pulse duration shock initiation properties by electric gun technology. For micro-TATB, the initiation threshold significantly decreases with TATB average size ranging from 79.7 μm to 0.5 μm. For 3D nanoporous TATB architecture, the initiation threshold decreases and then increases with specific surface areas increased from 9.6 m2/g to 36.2 m2/g. The lowest initiation thresholds are obtained for the micro-TATB with average sizes of 1.3 μm and 0.5 μm, and 3D nanoporous TATB architecture with specific surface area of 22.4 m2/g. The shock initiation thresholds of micro-TATB and 3D nanoporous TATB architectures show significantly decreases with the porosity increased. The decomposition reaction and thermal conductivity properties were further investigated to understand the initial response mechanism. High porosity provides more collapse sites to generate high temperature for formation of hot spots. The low thermal conductivity and decomposition temperature could enhance the formation and ignition of the hot spots, and initial decomposition reaction of TATB. The effect of the decomposition temperature is higher than that of the thermal conductivity on the shock initiation properties. The enhanced decomposition reaction could promote energy release and transfer process from the ignition to the combustion. This work offers a new insight to understand the effects of microstructure on the shock initiation properties and the initial response mechanism of TATB.  相似文献   

13.
The simulation of the artillery interior and intermediate ballistics problem is performed to investigate the influence of a gas dynamics device, muzzle brake, on the muzzle hazard phenomena, such as flash and blast waves. The correlation of the chemical reactions with the characteristics of the muzzle flow field is analyzed by the simulation for a further understanding of the secondary combustion phenom-enon of the muzzle flow. The novel structure of muzzle flow caused by the muzzle brake is presented by the simultaneous solution of the interior ballistics model and multi-species Navier-Stokes equations in order to analyze the influence of the muzzle brake structure on the chemical reactions. The secondary combustion of the muzzle flow due to the oxygen-supplement chemical reactions is obtained by the chemical reaction kinetic model. The interaction of the blast waves released from the muzzle brake is illustrated in detail and the mechanism of the formation of muzzle flash is analyzed. This research provides a reference for the studies on the suppression of the muzzle flash.  相似文献   

14.
为预报化学反应过程,应用DSMC方法研究了双原子分子的离解反应,讨论了高温情况下(T~Ea/k)采用由实验测定得到的反应速率与气体温度间Arrhenius经验关系式的可靠性问题,分析了振动热非平衡效应对于离解反应速率的影响,给出了由DSMC方法得到的离解反应速率与气体温度的关系曲线。  相似文献   

15.
The inspection game is a two-player noncooperative game that models a situation where an inspector verifies whether the inspectee complies with the rules (on the assumption that the inspectee has the tendency to violate at least one of the rules). The usual approach in the analysis of this game seeks to find an optimal strategic inspection scheme for each of the two players yielding favorable payoffs. Recently, there have been some developments in the study of such games that use a mathematical structure known as reaction network involving a set of molecular species and the existing reactions among these species. In this paper, we use a reaction network to analyze the inspection game giving an alternative way of modeling the social situation. The molecular species play the role of the players' decision moves and their resulting gain or loss, while the reactions are the encounters of the decisions of the players which, as expected, yield payoffs. We reexamine the dynamics of the inspection game through the lens of reaction network theory and consider various situations that call for more detailed analyses such as equal or unequal reaction rates and inspection leadership. Conditions concerning reaction rates, initial population of decision species, benefits, and costs are determined in order to identify strategies that yield better payoffs both for the inspector and inspectee. These results illustrate practical insights rooted from the formulated simple game models.  相似文献   

16.
17.
传统的Reimer-Tiemann反应产率不高(一般低于35%).通过改进反应条件,控制反应过程,使产率提高到60%,并对反应中的有关问题进行了讨论.  相似文献   

18.
本文对溴酸盐体系中的化学波进行了实验研究,得到了反应物的初始浓度与波速的关系,随 KBrO3和 H2SO4初始浓度的增加,波速具有增加的趋势,而随 MA的初始浓度的增加而变化不大。并给出了其反应机理的分析及数学模型。  相似文献   

19.
危险的致癌物质——亚硝胺   总被引:8,自引:0,他引:8  
环境中的有毒的致癌物质越来越多 ,亚硝胺就是其中一种。虽然它在环境中含量并不大 ,但由于它来源的广泛性和致癌机理的特殊性 ,已引起了人们的高度重视。本文对亚硝胺的来源、形成条件、致癌机理及控制方法作了探索性研究  相似文献   

20.
本文对渗碳气氛进行热力学及动力学分析,给出炉气各组分间反应速率的测试方法及测试数据。结果表明,渗碳气氛的独立反应数为4,自由度为3,甲烷的渗碳作用不可忽略,控制甲烷这一碳源有利于提高碳势控制精度.  相似文献   

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