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1.
利用B3LYP/6-311+G(2d,p)方法对一种新型含能增塑剂双(2,2-二硝基丙基)甲缩醛进行几何优化,计算了其红外光谱、生成焓和爆轰特性. 分析了最弱键的键离解能和键级并预测了目标化合物的热稳定性. 结果表明双(2,2-二硝基丙基)甲缩醛中的四个N-NO2键的键离解能都为164.38 kJ/mol. 表明目标化合物是一个热力学性能稳定的化合物. 以凝聚相生成焓和分子密度为基础,采用Kamlet-Jacobs方法预测其爆速和爆压. 目标化合物的晶体结构属于P21空间群.  相似文献   

2.
在DFT-B3LYP/6-31G*水平求得苯和苯胺类硝基衍生物的全优化分子几何和电子结构。通过非限制性 (U) B3LYP/6-31G*计算求得标题物各化学键离解能(BDE)。用UHF-PM3 MO方法求得引发键C-NO2键均裂反应的活化能(Ea)。以静态指标(键集居数、前线轨道能级差和硝基上净电荷)和动态理论指标(BDE和Ea) 阐明了热解引发机理,关联了实验撞击感度。运用SPSS程序关联静态和动态理论指标,表明它们可平行或等价地用作预示标题物的热解引发机理和撞击感度。  相似文献   

3.
在DFT-B3LYP/6-31G*水平获得苯和苯胺类硝基衍生物的全优化分子几何和电子结构.通过非限制性(U)B3LYP/6-31G*计算求得标题物各化学键离解能(BDE).用UHF-PM3 MO方法求得引发键C-NO2键均裂反应的活化能(Ea).以静态指标(键集居数、前线轨道能级差和硝基上净电荷)和动态理论指标(BDE和Ea)阐明了热解引发机理,关联了实验撞击感度.运用SPSS程序关联静态和动态理论指标,表明它们均可以用作预示标题物的热解引发机理和撞击感度.  相似文献   

4.
正Angew.Chem.Int.Ed.2018,57,5501~5505有机偕二硼化合物由于具有选择性地进行单官能团以及双官能团化的潜力而受到越来越多的关注.然而,目前有机偕二硼化合物的选择性双官能团化依旧具有许多挑战.当有机偕二硼中的一个C—B键进行官能化之后,第二个C—B键的反应活性往往会降低.但是,将偕二硼中的一个C—B键首先接入酰基能够以形成烯醇硼的形式直接活化第二个C—B键,从而实现有机偕二硼的双官能化.中国科学院兰州化学物理研究所苏州研究院/羰基合成与选择  相似文献   

5.
用SCF-MO-AM1方法计算研究了1,3,3-三硝基氮杂环丁烷和它的三个衍生物的分子几何构型,电子结构和热解机理,分子中连结偕二硝基的两个C-N键级较小,均裂该建所需活化能较低,可能是优先发生的主要热解引发反应,四个标题物均裂该键的活化能和该键的Wiberg键级之间存在良好的线性关系,线性相关系数为0.99。  相似文献   

6.
以硝基乙烷为原料, 经缩合、 氧化及酯化反应, 设计合成了含能增塑剂2,2-偕二硝基丙基三氟丙酸酯(DNPTFP); 利用核磁共振波谱、 红外光谱和元素分析对其结构进行了表征. 优化了DNPTFP的合成工艺, 确定酯化反应的较佳反应条件: 以甲苯为反应溶剂, n(2,2-偕二硝基丙醇)∶n(三氟丙酸)=1∶1.10, 催化剂浓硫酸的质量分数为5.0%, 反应温度110 ℃, 反应时间10 h. 在此条件下, DNPTFP的收率和纯度分别为75.2%和99.0%. 热分析测试结果表明, DNPTFP的玻璃化转变温度为-80.5 ℃, 热分解温度为267.59 ℃; 机械感度测试结果表明, DNPTFP的撞击感度为H50=125.9 cm, 摩擦感度为0, 说明DNPTFP具有良好的低温性能、 热稳定性及较低的机械感度. 此外, 相溶性试验、 黏度及玻璃化转变温度测试结果表明, DNPTFP与聚叠氮缩水甘油醚(GAP)相溶性良好, DNPTFP可显著调控GAP的黏度和玻璃化转变温度, 并且随其含量增加黏流活化能逐步降低, 增塑效率逐步升高. 因此, DNPTFP对GAP展现出优良的增塑效果, 在GAP基火炸药配方中有良好的应用前景.  相似文献   

7.
与传统N—O含能材料相比, N—F键调控的含能化合物因具有密度大、比冲高、与高热值金属燃烧放热量大等独特优势而受到各国研究人员的广泛关注.依据结构特点,N—F键含能化合物涵盖氟氮唑类含能化合物、二氟氨基二硝甲基化合物、偕二氟氨基化合物以及二氟氨基聚合物等4类含能化合物.综述了N—F键调控的含能化合物研究进展,重点探讨了N—F单键和二氟氨基引入策略以及其相关含能衍生物的合成技术途径,评述了典型氟氮含能化合物物化与爆轰性能.发展高效、安全、便捷的N—F键和二氟氨基合成方法,开发结构稳定、感度适中的新型N-氟唑类含能化合物、偕二氟氨基硝胺环状等高能量密度化合物将是含能材料领域重要的发展方向之一.  相似文献   

8.
周发岐  樊能廷 《化学学报》1985,43(5):484-486
Ponzio 用一系列芳香醛肟与四氧化二氮反应生成相应的芳基二硝基甲烷,曾用于合成苯环上有一个偕二硝基甲基取代的芳基二硝基甲烷;Rowley 和 Frankel 报道用 VictorMeyer 和 ter Meer 反应合成苯环上有两个偕二硝基甲基取代化合物,如对一双(二硝基甲基)苯(1a),但他们的方法和步骤繁冗,试剂昂贵,操作条件苛刻.我们曾报道运用 Ponzio 反应,由对苯二醛二肟合成la,并由间苯二醛二肟合成间-双(二硝基甲基)苯(1b).本文报道  相似文献   

9.
2-取代-5,5-二硝基嘧啶-4,6-二酮的合成和反应   总被引:1,自引:0,他引:1  
研究了2-取代嘧啶-4,6-二酮的硝化反应, 产物为2-取代-5,5-二硝基嘧啶-4,6-二酮(3), 收率>80%, 3与亲核试剂反应形成开环产物. 2-位取代基为烷基时, 嘧啶环5-位和侧链的α-位都发生反应, 当取代基为甲基时, 硝化产物为2-(二硝基亚甲基)-5,5-二硝基嘧啶-4,6-二酮(1), 1的水解产物为1,1-二氨基-2,2-硝基乙烯 (FOX-7) 和二硝基甲烷(2). 2-位取代基为羟基时, 硝化产物为5,5-二硝基巴比妥酸(7b), 7b水解可制得偕二硝基乙酰基脲(9b), 9b与KOH作用生成偕二硝基乙酰基脲钾盐(10b)和二硝基甲烷钾盐(11). 2-位取代基为氨基时, 硝化开环生成偕二硝基乙酰基胍(9a), 9a与KOH作用生成偕二硝基乙酰基胍钾盐(10a)和11. 当2-位无取代基时, 硝化产物无法分离, 结构推测为7c. 考察了亲核试剂对FOX-7收率的影响并对FOX-7的三种合成方法进行了评价, 对反应机理进行了探讨.  相似文献   

10.
金属铟参与醛衍生的N-酰基腙 1a-1q,4a-4g与3-溴-3,3-二氟丙烯 2 的反应,分别高效得到α, α-二氟高烯丙基肼 3a-3q,5a-5g。该反应条件温和,操作简便。硝基,酚羟基,苄氧基,α, β-不饱和醛的碳-碳双键等官能团对该反应具有良好的官能团兼容性。通过用锌粉代替铟粉, 酮衍生的N-酰基腙 6a-6d 也能发生偕二氟烯丙基化反应,以中等产率得到α, α-二氟高烯丙基肼 7a-7d。裂解肼3a的 N-N键顺利得到偕二氟高烯丙基胺 8,化合物 8 经丙烯酰化,随后进行RCM关环反应,可以方便的转化为偕二氟-γ-取代α, β-不饱和内酰胺 11。  相似文献   

11.
多环芳二酐型聚酯亚胺膜的透气性能李悦生,丁孟贤,徐纪平(浙江大学高分子科学与工程研究所,杭州,310027)(中国科学院长春应用化学研究所)关键词聚醚酰亚胺,聚酯酰亚胺,膜,透气性通常的聚酰亚胺加工性能较差,在芳环二酐的苯环间引入醚键等柔性基团后,其...  相似文献   

12.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

13.
14.
微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述,包括:微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。  相似文献   

15.
The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R2UPh type and -thioureas of the R2TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.  相似文献   

16.
朱劲波  马立群  梁飞  苗迎春  王立民 《应用化学》2015,32(11):1221-1230
Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB5型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。  相似文献   

17.
钒与糖代谢及糖尿病   总被引:1,自引:0,他引:1  
微量元素钒作为生物体内必需元素,经证实有很重要的生理学功能,与机体糖代谢有十分密切的关系,且能降低糖尿病动物模型的高血糖,极有可能被开发为治疗糖尿病的药物。  相似文献   

18.
In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.  相似文献   

19.
Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.  相似文献   

20.
Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.  相似文献   

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