多硝基芳香化合物撞击感度的量子化学研究

采用了ＰＭ３方法对一系列多硝基芳香类化合物进行了几何构型的全优化和平衡几何构型下的电子结构计算，结果表明，对于引发键为Ｃ－ＮＯ２的炸药分子，Ｍｕｌｉｋｅｎ键级顺序与实测的Ｈ５０顺序一致。Ｔｅｔｒｙｌ中引入ＮＨ２后，分子中的－Ｎ（ＣＨ３）（ＮＯ２）基团被活化。     

(7-N,N-二甲氨基)香豆素基-3-甲酸乙酯/二芳基碘鎓盐光敏引发聚合反应体系

本工作合成了（７－Ｎ,Ｎ－二甲氨基）香豆素基－３－甲酸乙酯（ＥＤＡＣＦ）光敏剂．在光作用下,激发态的ＥＤＡＣＦ分子与二芳基碘盐ＯＰＰＩＰ分子之间发生电子转移反应,伴随发生ＥＤＡＣＦ的褪色反应和ＯＰＰＩＰ的光解反应,后者生成具有引发活性的芳基自由基．由于ＥＤＡＣＦ具有ＣＴ态特性,使得它与ＯＰＰＩＰ之间的光电子转移反应速度随着溶剂极性增加明显减慢．ＥＤＡＣＦ／ＯＰＰＩＰ体系可有效地引发ＭＭＡ聚合反应,聚合反应动力学方程为Ｒｐ＝Ｋ［ＯＰＰＩＰ］０．４７［ＥＤＡＣＦ］０．４２［ＭＭＡ］０．９８．     

碱性介质中对硝基芳香醚的醚键稳定性研究

设计合成了对硝基苯乙醇、对硝基苯氧乙酸、对硝基苯氧丙酸、对硝基苯氧丁酸、对硝基苯丁醚等一系列的对硝基芳香醚,并以它们作为研究对象,对碱性介质中芳醚键的稳定性进行了研究。发现了对硝基苯氧丙酸亲核取代的异常情况,推测是分子内邻基参与的亲核取代反应。     

芳香氮杂环负离子与硝基取代的卤代苯的芳香亲核取代反应

1前言由于咪唑类化合物在生物体中所起的重要作用，使得该类化合物性质及反应的研究受到了人们广泛重视．八十年代初对该类化合物酸碱性的研究有了相继报道，Lopyrev和Blackburr等人对2,5-取代的苯并咪华和咪吐类化合物进行了1H和13CNMR的研究，并提出了化学位移与取代基效应关系的双参数方程，k吧加m实验亦证实了咪哩，苯并咪哩马等卤及硝基卤代烷的反应为SRNL反应机理。S＿等人研究了取代咪哩类化合物与三硝基取代末的反应．Rom等人合成了N－（4一二硝基苯）咪哩，并发现了咪哩基是一个较好的离去基团，并对此类化合物的肢解水解动…     

2—氯—4—溴苯酚气相色谱分析研究

本文介绍用５％ＯＶ－１０１,长度为１ｍ的不锈钢填充柱,以硝基苯为内标物,在１５０℃在柱温下用ＦＩＤ检测器对２－氯－４－溴苯酚进行定量分析。该法的变异系数为０．５４％,平均回收率９９．９６％,线性相关系数为０．９９９６。     

10-甲基-9-取代亚苄基-9,10-二氢吖啶类化合物的合成

１０－甲基－９－取代亚苄基－９,１０－二氢吖啶类化合物是很好的感光材料［１～３］,其结构式为：ＮＨ３Ｃ　　ＲＲ＝Ｈ（Ｉ）,ｏ－ＮＯ２（Ⅱ）,ｍ－ＮＯ２（Ⅲ）,ｐ－ＮＯ２（Ⅳ）,２,４－Ｄｉｎｉｔｒｏ（Ⅴ）,ｍ－Ｃｌ（Ⅵ）,ｐ－Ｃｌ（Ⅶ）,ｐ－ＯＣＨ３（Ⅷ）１　合成方法及讨论　　称取２．３４ｇ（７ｍｍｏｌ）洪埃试剂（按文献［４］制备）溶于７０ｍＬＴＨＦ中,在氮气保护下,搅拌冷却,于－７８℃下加入ｔ－ＢｕＬｉ的己烷悬浮液５ｍＬ（８ｍｍｏｌ）,溶液由无色变为黄色,待反应进行１０ｍｉｎ后加入溶有０．７４…     

0.20R2O-0.25CaO-0.55ZnO-Al2O3-SiO2系统的分相与析晶

本文通过大量的配方实验,利用ＯＭ、ＴＥＭ和ＸＲＤ分析,系统研究了０．２０Ｒ２Ｏ－０．２５ＣａＯ－０．５５ＺｎＯ－Ａｌ２Ｏ３－ＳｉＯ２系统的分相与析晶。研究结果表明,在Ａｌ２Ｏ３含量高于０．３０摩尔的区域可以获得乳浊程度和光泽度各异的析晶乳浊釉,在低铝区可获得分相乳浊釉,且乳浊程度随Ａｌ２Ｏ３含量的降低、ＳｉＯ２含量的提高而提高。用Ｎａ２Ｏ取代Ｋ２Ｏ,有利于瓷釉的析晶而不利于瓷釉的分相,分相区具有铝     

络合树脂法合成钙钛矿相复合氧化物

以ＬＢＣＦ（Ｌａ０．６Ｂａ０．４Ｃｏ０．２Ｆｅ０．８Ｏ３）为模型报道了络合树脂法合成多取代复合氧化物,并通过ＴＧ、ＦＴ—ＩＲ、ＸＲＤ、比表面测定技术考察了制备过程及所得粉体的性质。结果表明,制备过程中前驱体经自催化燃烧形成Ｍ—Ｏ键,进一步在８５０℃下煅烧,可以得到纯相钙钛矿复合氧化物。该法所得粉体粒径小,具有较大的比表面积,是一种好的制备多取代复合氧化物的方法     

La3+取代Bi3+的 Bi2O3-ZnO-Nb2O5基陶瓷的结构与介电性能

研究了Ｌａ２Ｏ３取代的Ｂｉ２Ｏ３－ＺｎＯ－Ｎｂ２Ｏ５（ＢＺＮ）基陶瓷Ｂｉ１．５－ｘＬａｘＺｎ０．５（Ｚｎ０．５Ｎｂ１．５）Ｏ７的结构和介电性能。采用固相反应法制备陶瓷样品,用Ｘ射线衍射技术分析样品的相结构,未用Ｌａ２Ｏ３取代的纯ＢＺＮ陶瓷的晶体结构为立方焦绿石单相;当Ｌａ２Ｏ３取代量较少时,样品的结构仍然保持立方焦绿石单相结构,但出现了超晶格衍射线（２１１）;当Ｌａ２Ｏ３取代量继续增加。样品的晶体     

溶胶—凝胶法制备SiO2膜的研究

研究了正硅酸乙酯和硅溶胶水解聚合过程中溶胶聚合物分子的生长过程。用ＴＥＯＳ和硅溶胶作原料。用溶胶－凝胶法制备了有载体和无体体的ＳｉＯ２膜，由不同原料引起的聚合物分子的不同生长模式将引起无载体ＳｉＯ２膜孔径的较大差异，用ＴＥＯＳ制得的无载体ＳｉＯ２膜无１．７ｎｍ以上的孔，而用硅溶胶制得的ＳｉＯ２膜平均孔径为７．５ｎｍ且孔径分布狭窄。用ＴＥＯＳ作原料可在载体α－Ａｌ２Ｏ３上制得无大孔缺陷厚约０．８μｍ     

黑梯炸药力学性能与感度的分子动力学研究

为了研究黑梯炸药配方对其力学性能与感度的影响,用Materials Studio软件建立了黑梯炸药的晶胞模型。采用分子动力学方法,计算了不同配方的黑梯炸药的力学性能、引发键键长分布、键连双原子作用能与内聚能密度,并对其变化情况并进行了比较。结果表明,在黑梯炸药中,随着RDX的质量分数从30%增加到80%,黑梯炸药的力学性能参数在一定范围内波动,其中拉伸模量变化范围为1.772 3~2.825 1GPa,剪切模量变化范围为0.636 6~1.042 8GPa,体积模量变化范围为2.734 1~3.747 9GPa,柯西压变化范围为1.203 2~2.181 6GPa,泊松比变化范围为0.354 6~0.397 0,而最大键长从0.155 4nm增至0.162 6nm,键连双原子作用能从167.6kJ/mol减至152.3kJ/mol,内聚能密度从0.899kJ/cm~3减至0.678kJ/cm~3,表明炸药的感度增大。     

外电场对HMX/DMI共晶感度影响的理论研究

为研究外电场对共晶含能材料HMX/DMI感度的影响,分别采用DFT-B3LYP-D3、M06-2X-D3和ωB97XD方法,在6-311+G(d,p)水平下,对HMX/DMI的稳定构型施加±0.005a.u.、±0.010a.u.、0.00a.u.的外电场,分析了电子密度转移、硝基基团电荷、分子表面静电势及引发键变化。结果表明,施加正向外电场时,电场强度越大,炸药感度越高。施加负向外电场时,电场强度越大,炸药感度越低;随着负向外加电场的增强,引发键电子云密度越大,引发键强度增大,导致HMX/DMI感度降低;负向外加电场增加,硝基基团所带负电荷由0.126e增至0.325e,感度降低;分子表面静电势研究分析表明,施加负向电场时,分子表面静电势增大,共晶感度降低;引发键变化分析表明,负向外加电场强度增加,引发键键长由0.1386nm降至0.1367nm,引发键键解离能由180.252kJ/mol增加到180.782kJ/mol,共晶化合物感度降低。     

PBX9501热感度、热膨胀及力学性能的分子动力学模拟

采用分子动力学模拟研究了不同温度和压强条件下PBX9501炸药的热感度、热膨胀和力学性能。通过体系中各组分最大引发键键长的变化判断温度对其热感度的影响;预测了PBX9501体系在不同温度下的热膨胀系数;采用静态力学理论分析其力学性能随温度和压强的变化。结果表明,在295~450K,随温度的升高,PBX9501炸药的敏感性增大,且在375K时其引发键的最大键长显著增大;热膨胀系数随温度升高而减小;随温度升高其脆性越明显,随压强的增加其韧性越好。     

ANPyO在不同温度下晶体感度和力学性能的分子动力学模拟

NPT系综下,用COMPASS力场对ANPyO超晶胞及沿其（4,0,-2）晶面切割的两种模型分别进行不同温度（195、245、295、345、395 K）下的分子动力学模拟。结果表明,随着温度的升高,ANPyO引发键最大键长递增,引发键双原子作用能和内聚能递减,这与炸药感度随温度升高而增大的事实相一致,一定条件下它们可作为炸药感度判定的理论依据。获得了5个温度下ANPyO和ANPyO（4,0,-2）的力学性能,从理论上揭示了其力学性能随温度递变的规律。     

Head-to-Head Comparison of Selected Extra- and Intracellular CO-Releasing Molecules on Their CO-Releasing and Anti-Inflammatory Properties

Over the past decade, a variety of carbon monoxide releasing molecules (CORMs) have been developed and tested. Some CORMs spontaneously release CO once in solution, while others require a trigger mechanism to release the bound CO from its molecular complex. The modulation of biological systems by CORMs depends largely on the spatiotemporal release of CO, which likely differs among the different types of CORMs. In spontaneously releasing CORMs, CO is released extracellularly and crosses the cell membrane to interact with intracellular targets. Other CORMs can directly release CO intracellularly, which may be a more efficient method to modulate biological systems. In the present study, we compared the efficacy of extracellular and intracellular CO-releasing CORMs that either release CO spontaneously or require an enzymatic trigger. The efficacy of such CORMs to modulate HO-1 and VCAM-1 expression in TNF-α-stimulated human umbilical vein endothelial cells (HUVEC) was evaluated.     

Theoretical study on vapour phase Beckmann rearrangement of cyclohexanone oxime over a high silica MFI zeolite

We have studied an activation mechanism of cyclohexanone oxime in a cavity of high silica MFI zeolite by using PIO analysis proposed by Fujimoto et al. DFT calculation reveals that the bond length of N–OH becomes longer when water coordinates on oxygen of oxime. The PIO clearly shows out-of-phase interaction between N and O. This out-of-phase interaction is also observed in the PIO of oxime/MFI zeolite cluster model and weakens the N---O bond. Hydrogen bond of Si–OH of nest silanols to oxime is a trigger of vapour phase Beckmann rearrangement.     

Relationships between Impact Sensitivity and Molecular Electronic Structure

A very simple calculational procedure is used to investigate the electronic structure of several classes of organic explosives (polynitroaliphatics with trinitromethyl or fluorodinitromethyl groups, polynitroaromatics, polynitroaliphatic nitramines and aliphatic nitrate esters). The method utilizes a bond electronegativity equalization principle. It is shown that atom charges, bond electronegativities and charge transferred in a bond are all potential indicator quantities for predicting impact sensitivity trends for the various classes. Specifically it is shown that charge transferred to the nitro group through a trigger linkage (C NO₂, N NO₂, O NO₂) can classify and correlate impact sensitivity trends in the compounds studied here. The results also indicate that electronic structure is not sufficient by itself to understand the phenomenon. This work in conjunction with previous work⁽¹⁾ shows that both a global quantity (i.e. related to the whole molecule) and a local quantity (i.e. related to the trigger linkage) are needed to understand impact sensitivity behavior.     

Modification of Surfaces to Meet Bioadhesive Design Goals: A Review

The modern range of medical devices presents contrasting requirements for adhesion in biological environments. Strong bioadhesion is desired in many circumstances to assure device retention and immobility. Minimal adhesion is absolutely essential in others, where thrombosis or bacterial adhesion would destroy the utility of the implants. A brief review is given of some analytical approaches, based in adhesion science, most useful in addressing these needs. Familiar correlating parameters, such as the critical surface tension, are surprisingly good in predicting bioadhesive outcomes such as tissue integration. The example of dental implants is given to illustrate this correlation. In every case, primary attention must be given to the qualities of the first interfacial conditioning films of bio-macromolecules deposited from the living systems. For instance, fibrinogen deposits from blood may assume different configurations on surfaces of different initial energies, and thus trigger different physiological events. Standard surface modification techniques, such as siliconization, when properly quality controlled can yield improved blood-compatible devices like substitute blood vessels and artificial heart sacs. Promising extensions to new areas of biotechnology are forecast.     

聚氨酯与金属粘接用耐热底胶的研制

以环氧树脂、端羧基了腈橡胶、TDI、双氰胺等为原料制备了一种用于粘接聚氨酯弹性体与金属的耐热底胶。讨论了端羧基丁腈橡胶用量、固化剂用量等因素对粘接强度的影响。此底胶具有耐热性能并改善了聚氨酯弹性体与金属之间的粘接性。     

Comparison of methods for evaluating bond strength between concrete substrate and repair materials

This investigation was aimed at studying the effect of test methods on bond strength between concrete substrate and repair material. Four test methods with cementitious or modified-cementitious repair materials, and two surface roughnesses were studied. The methods used were pull-off, slant shear, splitting prism and a new direct shear named Bi-Surface shear test. While the coefficient of variation (COV) for each type of test was acceptable, the bond strengths from some tests were up to eight times larger than those obtained from others. It is imperative that the bond tests be selected such that they represent the state of stress the structure is subjected to in the field. The new test method was easy to carry out and had reasonable results and can be developed by further investigations.