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1.
1呋咱类化合物的合成含呋咱(氧化呋咱)环的含能化合物具有许多优异的炸药性能:标准生成焓高,富含氮氧,能量密度高,分子稳定性好,熔点较低。3,4-二(硝基呋咱基)氧化呋咱(DNTF)威力大,能量高,接近CL-20,安全性能较HMX和CL-20好,在熔铸炸药、推进剂及柔性导爆索等领域有着广阔的应用前景。DNTF属第四代高能炸药。  相似文献   

2.
以呋咱环为基本结构单元可以构建多系列性能优异的新型呋咱含能衍生物,它们一般具有能量密度高,标准生成焓大,氮含量高以及分子热力学稳定性较好等优点。3-叠氮-4-氨基呋咱(AAF)作为合成三唑联呋咱、多叠氮基呋咱、呋咱醚、腈基呋咱等多类含能化合物的重要中间体,而且本身也是一个高能量密度化合物,因此探讨其合成方法具有一定的意义。3-叠氮-4-氨基呋咱的合成路线如图1所示,合成分为3步:第一步是乙二醛与盐酸羟胺在氢氧化钠溶液中发生加成缩合反应得N-氨基乙二肟(DAG)。该反应具有强放热性,实验操作应小心。  相似文献   

3.
杂环硝胺是重要的含能化合物,研究表明:用羰基取代环胺中的次甲基,可以提高炸药的结晶密度,进而提高爆速,比如硝基甘脲及我国20世纪70年代就已合成的六硝基六氮杂三环十二烷二酮。如果将呋咱基引入到氮杂稠环类化合物分子结构中,以取代结构中的羰基,则又有可能创造一类密度及能量都非常高的炸药。基于该思想,文中利用两种化合物DAF和1,4-甲酰基-2,3,5,6-四羟基哌嗪(DFTHP),合成了目标炸药分子:六硝基六氮杂三环十四烷对二呋咱(HHTTD)及前体化合物六氮杂三环十四烷对二呋咱(HTTD)。文中给出了HTTD的合成方法及HTTD的硝化反应,提出了一种新化合物HHTTD的合成方法并对羟胺缩合反应进行了较详细的研究,HTTD及HHTTD的结构见图1。  相似文献   

4.
本文对53种NnHn(n=3~7)氮氢化合物进行了理论计算,应用自然键轨道理论(Nature Bond Orbital, NBO)和分子中的原子理论(Atoms In Molecules, AIM)分析了化合物的成键特征、相对稳定性。氮原子孤对电子与氮氮键以及氮氮键相互之间的超共轭作用是影响氮氮键长的重要因素。采用原子基团法,比较了化合物的原子基团能量和原子基团生成热。通过预测53种化合物的稳定性,找出了氮氢化合物的稳定性与结构之间的一些规律,为预测氮氢化合物的稳定性提供了新的方法和新的数据。  相似文献   

5.
本文计算了甲基(-CH3),羟基(-OH)对1-丁氮烯和2-丁氮烯的取代基效应.1-丁氮烯引入取代基后.N=N双键的键长变短,而N-N单键的键长增长.异构体2-丁氮烯的键长变化较小.引入甲基或羟基后,N原子的孤对电子会与相应的N-C(N-O)键之间发生相互作用,使整个分子的超共轭作用增强.随着取代基数目的增多,总能量和生成热就会降低,取代基数目与分子能量(生成热)之间具有很好的相关性.  相似文献   

6.
含有硝酰氧基和硝胺基团的含能化合物,对撞击、摩擦和静电火花的刺激相当敏感,而含有呋咱、偶氮、氧化偶氮和C-NO2等基团的杂环含能化合物的感度较低,以呋咱基团为基的含能衍生物由于具有能量密度高、标准生成焓大、氮含量高和耐热性能优良等优点,目前已成为重要的高能量密度材料。  相似文献   

7.
3,4-二(硝基呋咱基)氧化呋咱(DNTF)是一新型高能量密度化合物,其感度较HMX的低,能量较HMX的高,与CL-20的相当。文中对DNTF及其中间体3-氨基-4-酰胺肟基呋咱(AAOF),3-氨基-4-酰氯肟基呋咱(ACOF),3,4-二(氨基呋咱基)氧化呋咱(DATF)及其异构体3,6-二(3'-氨基呋咱基-4-基)-1,4-二氧杂-2,5-二氮杂环己-2,5-二烯(BADDD)的合成,表征和主要的物化和炸药性能进行了报道。  相似文献   

8.
本文计算了甲基(-CH3),羟基(-OH)对1-丁氮烯和2-丁氮烯的取代基效应。当1-丁氮烯引入取代基后,N=N双键的键长变短,而N-N单键的键长增长。异构体2-丁氮烯的键长变化较小。当引入甲基或羟基后,N原子的孤对电子会与相应的N-C(N-O)键之间发生相互作用,使整个分子的超共轭作用增强。随着取代基数目的增多,总能量和生成热就会降低,取代基数目与分子能量(生成热)之间具有很好的相关性。  相似文献   

9.
本文报道了二苯胺、甲基苯基胺、甲潜苄胺、二苄胺、二异丙胺和二乙胺分别与苯并呋咱-1-氧化物在紫外光照下发生光化学反应的电子自旋共振(ESR)研究结果。结果表明:紫外光的作用首先使苯并呋咱-1-氧化物处于激发态,它与二胺作用生成激基态络合物,经氧转移和二胺的氮氢键断裂而最终生成相应的氮氧自由基。  相似文献   

10.
发现并揭示了2-酮基-L-古龙酸在许多种溶剂中发生了结构改变,该物质在室温条件下,无需施加任何外力因素,分子中极易发生分子内成环结构变化:分子中的羰基(-C=O)双键断开变单键,形成了2,5位半缩醛五元环衍生物,使分子内出现了O-C-O基团,其标题化合物的核磁共振碳谱(13C NMR)羰基特征峰的化学位移(约200)变到了96,核磁共振2D HMBC异核相关谱,充分证明了2-酮基-L-古龙酸发生的分子内环合成衍生物的主要产物是五元环的2,5位半缩醛衍生物,而非六元环的2,6位半缩醛衍生物.  相似文献   

11.
Ab initio calculations including electron correlation are still extremely costly, except for the smallest atoms and molecules. Therefore, our purpose in the present study is to employ a bond-order correlation approach to obtain, via equilibrium molecular energies, molecular dissociation energies and heats of formation for some 20 molecules containing C, H, and O atoms, with a maximum number of electrons of around 40. Finally, it is important in the proposed procedure to include electron correlation effects in the basis set choice when determining thermodynamic properties. With the optimum choice of basis set, the average percentage error for some 20 molecules is approximately 20% for heats of formation. For molecular dissociation energies the average error is much smaller: ~0.4%.  相似文献   

12.
Using density functional theory (DFT), a series of bis(1H-tetrazol-5-yl)furazan and bis(1H-tetrazol) derivatives with different linkages and substituents are investigated theoretically as potential high-energy-density materials (HEDMs). The heat of formation (HOF), detonation properties, natural bond orbital (NBO) and thermal stabilities are calculated and reported. The introduction of a furazan ring, an –N=N– bridge group and an –N3 substituent is beneficial to increase the HOF of the title compounds. NBO analysis shows that there are electronic delocalisation effects among the bridge groups, furazan and tetrazole rings, and substituted groups. The conjugation effects and electronic transitions are influenced by the different linkages and substituents. The estimated detonation velocities and pressures indicate that the –ONO2 and –NO2 groups and the –N=N– linkage play important roles in enhancing the detonation properties. The bond dissociation energy (BDE) calculations reveal that the –NO2 group is the substituent group which causes the least thermal stability. The bond between the substituent group and the tetrazole ring is the weakest bond in the title molecules. Considering the detonation performance and the thermal stability, 17 compounds may be promising candidates for HEDMs with good performance. Eight of them (A3, A4, C3, C4, D3, F3, G1 and G3) have better detonation properties than HMX.  相似文献   

13.
The density functional theory method was used to study the heats of formation (HOFs), energetic properties, electronic structure of a series of 4,4″‐dinitro(3,3′:4′,3′′)tris([1,2,5]oxadiazole)‐2′‐oxide (3,4‐bis[4′‐nitrofurazan‐3′‐yl]furoxan) derivatives. The results show that the substitution of the nitro group is very useful for improving their HOFs and detonation performances. The HOFs of the title compounds are all positive and larger than those of 1,3,5‐trinitro‐1,3,5‐triazinane and 1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocane. The analysis of oxygen balance shows that the studied compounds need the oxygen in the explosive. Compound A1 has larger detonation velocity and detonation pressure than those of 1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocane and can be regarded as a potential candidate for high‐energy compounds because of the moderate heat of detonation, high density, and high N. In addition, the energy gaps between the highest occupied molecular orbital and lowest unoccupied molecular orbital of the studied compounds are further investigated.  相似文献   

14.
Gas‐phase heats of formation (HOF), solid‐phase HOF, detonation properties, electronic structure and thermal stability for a series of polynitro pyrazine derivatives containing three heterocycles have been investigated using density functional theory. It is found that the nitro group is an efficient tool to improve HOF of pyrazine derivatives. Furthermore, detonation velocities and detonation pressures of these compounds are evaluated using empirical Kamlet–Jacobs equations. As a result, it indicates that the nitro group is useful to enhance detonation properties. Detonation velocities of five compounds are 9.67, 9.20, 9.74, 9.76 and 9.87 km/s, respectively, which are significantly larger than that of HMX (9.10 km/s). Bond dissociation energy is also performed to investigate their thermal stability, showing that thermal stability of these compounds is little affected by nitro groups or the position of substituent groups. Considering solid‐phase HOF, detonation properties and thermal stability, some of pyrazine derivatives can be potential high energy density materials. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
Molecular mutagens and carcinogens are structures which carry chemical and electronic properties that disturb and interact with the genomic machinery. Principally, a rule of thumb for carcinogens is that carcinogens are expected to introduce covalent irreversible bonding to one or several types of DNA bases, causing errors in the reading frame for the polymerases. 8‐methoxy‐6‐nitrophenanthro[3,4‐d][1,3]dioxole‐5‐carboxylic acid, better known as Aristolochic acid (AA1) is a recognized carcinogen which causes urotherial cancer and is found in certain plants. Its structure is particularly interesting given that it is closely related to phenanthrene in its polycyclic arrangement, and has four functional groups, a carboxyl‐, a nitro‐, a methoxy‐ and a dioxolane group. In this work, the structure of AA1 has been resolved at the MPWPW91 density functional theory method in combination with Aug‐cc‐pVDZ basis sets. A geometry analysis shows that in AA1 the carboxyl group's torsion is caused by steric strain from the nitro group, which elevates the molecular plane of the first phenanthrene ring with 0.1Å. The wavefunction analysis of AA1 shows that the ring deformation enhances a double π‐bond localization in the first ring, adjacent to the dioxalane group, and results in a decrease of ring aromaticity and induces a potentially frozen resonance. Intermolecular and intramolecular interactions were characterized by atoms in molecules and reduced density gradient analysis. This study brings novel information on the geometry and electronic structure of AA1, which are important for the further knowledge of its transformation in vivo and in situ. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

16.
Density functional theory method was used to study the heats of formation, energetic properties, and thermal stability for a series of trinitromethyl‐substituted tetrazole and tetrazine derivatives with different substituents. It is found that the group ―NO2, ―NHNO2, or ―NF2 play a very important role in increasing the heats of formation of the derivatives. The calculated detonation velocities and pressures indicate that the group ―CF2NF2, ―NHNO2, ―1H‐tetrazolyl, ―2H‐tetrazolyl, or ―1,2,4,5‐tetrazinyl is an effective structural unit for enhancing their detonation performance. An analysis of the bond dissociation energies for several relatively weak bonds indicates that incorporating the group ―NHNO2 and ―NH2 into parent ring decreases their thermal stability. Considering the detonation performance and thermal stability, 37 compounds may be considered as the potential high‐energy compounds. Their oxygen balances are close to zero. These results provide basic information for the molecular design of novel high‐energy compounds. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

17.
基于定量结构-活性相关(QSAR)研究硝基苯类化合物的性质具有重要意义.采用分子电性作用失量(MEIV)表征硝基苯类有机毒物的分子结构,运用多元线性回归建立定量结构毒性相关(QSTR)模型,同时采用逐步回归结合统计检测筛选模型变量,建立了25个硝基苯类化合物对斜生栅藻(Scenedesmusobliquus)的急性毒性与其结构间的回归方程.另外采用内部及外部双重验证的办法深入分析和检验模型的稳定性.建模的复相关系数(R_(cum)~2)、留一法(LOO)交互校验复相关系数(R_(CV)~2)和外部样本校验复相关系数(Q_(ext)~2)分别为0.927、0.872和0.908.表明用MEIV表征硝基苯类有机物分子结构信息较好,所建QSTR模型的稳定性和预测能力良好.  相似文献   

18.
基于定量结构-活性相关(QSAR)研究硝基苯类化合物的性质具有重要意义。采用分子电性作用失量(MEIV)表征硝基苯类有机毒物的分子结构,运用多元线性回归建立定量结构毒性相关(QSTR)模型,同时采用逐步回归结合统计检测筛选模型变量,建立了25个硝基苯类化合物对斜生栅藻(Scenedesmus obliquus)的急性毒性与其结构间的回归方程。另外采用内部及外部双重验证的办法深入分析和检验模型的稳定性。建模的复相关系数(Rcum2)、留一法(LOO)交互校验复相关系数(RCV2)和外部样本校验复相关系数(Qext2)分别为0.927、0.872和0.908。表明用MEIV表征硝基苯类有机物分子结构信息较好,所建QSTR模型的稳定性和预测能力良好。  相似文献   

19.
20.
Temperature dependence of magnetic anisotropy of homologous nematic fluorinated phenyl bicyclohexane liquid crystals is measured by a magneto-electric method.The result shows that the diamagnetic property is slightly influenced by the positions and the numbers of fluorine atoms substituted at the phenyl ring.By investigating the correlation of the dielectric anisotropy with the magnetic anisotropy,a novel explanation is proposed for the behaviour of the molecular dipole-dipole dimerization in the polar liquid crystal compounds.  相似文献   

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