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1.
在DFT-B3LYP/6-311++G**水平上,研究了硝基环丁烷及其衍生物和硝基环己烷C-NO2 和 N-NO2 键的中点、环上方分子表面静电势及其统计量,建立了三种标题化合物实验撞击感度h50与分子表面静电势及其统计量之间的定量关系。结果表明,这些模型的相关性较差。然而,环张力贡献的引入使其相关性增强。作为一种表征分子全局性质的物理量,分子表面静电势可用于预估炸药分子的感度。随着实验数据的增多,建立撞击感度h50与分子表面静电势及其静电势的统计量之间的定量关系是有必要的。  相似文献   

2.
运用密度泛函DFT-BHand HLYP/6-311G**方法,对八种三硝基芳香族炸药分子进行全优化、能量频率计算,研究其各自的活化能、表面静电势等几种统计量.建立起这八种化合物实验撞击感度h50与分子表面静电势及统计量之间的定量关系,结果发现其相关系数很大(0.91+).随后引入活化能影响因子,在撞击感度与分子活化能、分子表面静电势及其统计量之间建立关系模型,结果表明撞击感度与活化能、表面静电势及其他统计量之间存在很好的相关关系(0.95+).这对预估炸药分子的撞击感度值有一定意义.  相似文献   

3.
硝基甲苯类炸药C-NO2键中点的静电势   总被引:3,自引:2,他引:1  
利用HONDO程序包,采用从头计算法对硝基甲苯类炸药的分子结构及其C-NO2键中点的静电势进行了计算,讨论了硝基甲苯类炸药C-NO2键中点的静电势最大值Vmidmax与其实验撞击感度之间的关系.研究表明:对于硝基甲苯类炸药,可用其分子C-NO2键中点的静电势最大值Vmidmax来确定其撞击感度的变化趋势.以静电势为判据,讨论了硝基和甲基数目以及硝基和甲基的相对位置对这类炸药撞击感度的影响.  相似文献   

4.
利用HONDO程序包,采用从头算法对硝基苯胺类炸药的分子结构和电偶极矩等性质以及 C-NO2键中点静电势等进行计算,讨论了硝基苯胺类炸药C-NO2键中点静电势最大值Vmidmax与其实验撞击感度之间的关系.研究表明:对于硝基苯胺类炸药,不宜单独用C-NO2键中点静电势最大值Vmidmax来表征撞击感度的变化,但可以用静电势最大值Vmidmax与电偶极矩的积来确定其撞击感度的变化趋势,讨论了硝基和胺基的相对位置以及硝基和胺基的数目对这类炸药感度的影响.  相似文献   

5.
五种典型硝苯胺类炸药的静电势与撞击感度的关系研究   总被引:2,自引:0,他引:2  
利用NONDO程序包,采用双头算法对硝基苯胺类炸药的分子结构和电偶极矩等性质以及C-NO2键中点静电势等进行计算,讨论了硝基苯胺类炸药C-NO2键中点静电势最大值Vimidmax与其实验撞击感度之间的关系。研究表明:对于硝基苯胺类炸药,不宜单独用C-NO2键中点静电势最大值Vmidmax来表征撞击感度的变化,但可以用静电势最大值Vmidmax与电偶极矩的积来确定其撞击感度的变化趋势,讨论了硝基和胺基的相对位置以及硝基和胺基的数目对这类炸药感度的影响。  相似文献   

6.
多硝基苯酸酯炸药分子键离解能与撞击感度关系研究   总被引:1,自引:1,他引:0  
用密度泛函方法,在B3LYP-6-31G*、B3P86/6-31G*和B3LYP-6-311G*三种理论水平对四个含硝基烷基的苯酸酯炸药分子进行了几何结构全优化、能量和频率计算。并对这些炸药分子苯环上的C-NO2和烷基上的C-NO2键离解能分别进行了三种理论水平的计算。结果表明,这类分子中的最弱键是烷基上的C-NO2键。进一步分析实验撞击感度与分子中最弱键离解能量的关系,结果表明,分子最弱键离解能与分子总能量的比值BDE/E和实验撞击感度h50%之间存在一个几乎线性的关联关系。BDE/E是表征炸药撞击感度的一个实用的合理指针。  相似文献   

7.
用密度泛函方法,在B3LYP/6-31G*水平对五个含硝基烷基的硝基芳香族炸药分子和四个含硝基烷基的苯酸酯炸药分子进行了几何结构全优化、能量和频率计算.并分别对这两类炸药分子苯环上的C-NO2和烷基上的C-NO2键离解能进行了同等水平的计算.结果表明,这两类分子中的最弱键均是烷基上的C-NO2键.进一步分析实验撞击感度与分子中最弱键离解能量的关系.结果表明,最弱键离解能BDE是表征炸药撞击感度的重要指针,但不是唯一指针.除了BDE,炸药的撞击感度可能还受其它因素或反应途径的影响.  相似文献   

8.
在133LYP/6.31 G*理论水平上优化了一系列取代硝基苯类化舍物的几何构型,计算了它们的电子结构和Wiberg键级,结果表明,随着氨基的引入,起爆引发键C-NO2键的强度有可能得到加强,炸药的撞击感度减小.讨论了分子内氢键与其撞击感度的关系,结果表明氢键的形成可能对分子的撞击感度起钝化作用.讨论了C-NO2键的强弱与其位置的关系.  相似文献   

9.
本文模拟计算了2,2’,4,4’,6,6’-六硝基联苯(HNBP)、2,2’,4,4’,6,6’-六硝基二苯乙烯(HNS)、2,5-二苦基-1,3,4-噁二唑(DPO)和5,5''-双(2,4,6-三硝基苯基)-2,2''-双(1,3,4-噁二唑)(TKX-55)四种耐热含能化合物的分子结构、Mulliken电荷布居、分子静电势(MEP)和Hirshfeld表面, 通过研究其分子特性、电子特性以及分子间相互作用, 以了解高耐热性含能化合物的耐热机理. 结果表明, 桥连接结构的复杂性以及分子间强氢键相互作用会增强含能化合物的稳定性. 此外, 本研究还发现中间基团的加入会对四种含能化合物分子两侧芳香环上碳原子的电荷分布以及分子表面正负静电势区域面积产生一定的影响.  相似文献   

10.
应用已建立的关于金属表面吸附层中表面应力的统计热力学理论 ,计算了Au(111)上烷烃硫醇SAMs的表面应力及其与烷烃硫醇链长、吸附覆盖度的定量关系 .计算结果与实验相符 ,较好地解释了Berger等人的实验结果 ,特别是解决了在表面应力符号性质上理论与实验的矛盾 .在表面吸附层应力的多种物理起源中 ,通过底物的分子间作用力有着决定性的贡献 ,揭示了分子的吸附能间接地起着重要作用 .这与阴离子化学吸附体系Cl-/Au(111)的有关研究结果相同 .  相似文献   

11.
Cosmologically stabilizing radion along with the dilaton is one of the major concerns of low energy string theory. One can hope that T and S dualities can provide a plausible answer. In this work we study the impact of S and T duality invariances on dilaton gravity. We have shown various instances where physically interesting models arise as a result of imposing the mentioned invariances. In particular S duality has a very privileged effect, in that the dilaton equations partially decouple from the evolution of the scale factors. This makes it easy to understand the general rules for the stabilization of the dilaton. We also show that certain T duality invariant actions become S duality invariance compatible. That is, they mimic S duality when the extra dimensions stabilize.  相似文献   

12.
There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project. The length of the tunnel is about 20 m. The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered by soil for shielding. In order to reduce the dose rate at the exit of the cable ducts, we use the ISIS construction, which is designed with four turnings, as a reference for the tunnel design. The thickness of the shielding is obtained by a simulation with the Monte Carlo Code FLUKA. The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved. This paper provides the basis for the design of the tunnel.  相似文献   

13.
There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project.The length of the tunnel is about 20 m.The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered ed soil for shielding.In order to reduce the dose rate at the exit of the cable ducts,we use the ISIS construction,which is designed with four turnings,as a reference for the tunnel design.The thickness of the shielding is obtained by a simulationwith the Monte Carlo Code FLUKA.The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved.This paper provides the basis for the design of the tunnel.  相似文献   

14.
15.
The Umkehreinwand of Loschmidt and the Wiederkehreinwand of Zermelo have been reexamined. The former paradox depends on the augument that for a dynamical system, upon the reversal of the velocities of all the molecules, theH function retraces its sequence of values so thatdH/dt will change its sign. The latter paradox depends on the argument that theH function returns infinitely close to its value after a Poincare' quasi-period and therefore cannot be decreasing all the time. While the main contention of the two paradoxes is correct, that theH theorem is inconsistent with classical dynamical laws, the arguments there can be considerably simplified and the “paradoxes” answered more directly. If the distribution functionf(q K ,p K ,t) is governed by an equation which is time-reversal invariant (such as the Liouville equation for a closed dynamical system), then it can be shown immediately thatdH/dt=0,H=cons. In this case, both paradoxes disappear, but together with them, thedH/dt<0 part of theH theorem also has disappeared, i.e., there is no second law of thermodynamics. Iff(q K ,p K ,t) is governed by an equation which is not time-reversal invariant (such as the Boltzmann equation, or the Master Equation for Markovian processes), then (1) there is no argument forf andH(t) to retrace their sequence of values upon the reversal of all the velocities of the system, (2) there is no quasiperiod in whichf andH(t) return to their earlier values. In this case, both paradoxes disappear also, but then one must go beyond classical dynamics in order to maintain theH theorem.  相似文献   

16.
In this work we study in detail the connection between the solutions to the Dirac and Weyl equations and the associated electromagnetic four-potentials.First,it is proven that all solutions to the Weyl equation are degenerate,in the sense that they correspond to an infinite number of electromagnetic four-potentials.As far as the solutions to the Dirac equation are concerned,it is shown that they can be classified into two classes.The elements of the first class correspond to one and only one four-potential,and are called non-degenerate Dirac solutions.On the other hand,the elements of the second class correspond to an infinite number of four-potentials,and are called degenerate Dirac solutions.Further,it is proven that at least two of these fourpotentials are gauge-inequivalent,corresponding to different electromagnetic fields.In order to illustrate this particularly important result we have studied the degenerate solutions to the forcefree Dirac equation and shown that they correspond to massless particles.We have also provided explicit examples regarding solutions to the force-free Weyl equation and the Weyl equation for a constant magnetic field.In all cases we have calculated the infinite number of different electromagnetic fields corresponding to these solutions.Finally,we have discussed potential applications of our results in cosmology,materials science and nanoelectronics.  相似文献   

17.
通过对三大岩类中15种岩石样本(样本总数目达208块)进行取样测定,获得其密度、磁化率以及波段350~2 500 nm的反射光谱数据。以研究岩石物性(密度及磁化率)与其不同波段反射率相关性,求取了相关系数曲线。根据试验结果曲线,进一步对具有岩石反射率定性及定量探讨岩石密度及磁化率前景的岩石种类及波段进行了总结,并且对几种岩石相关系数曲线的特征进行了归纳。认为通过岩石反射率间接获取岩石密度及磁化率的研究思路具有一定意义及可行性。  相似文献   

18.
The investigation was made of the dependence of the intensity of Tl, Ga, Mo, Mg, Mn, Sn, Bi, Ni, Zn, Pt and Au spectral lines and the plasma parameters (temperature T, electron concentration ne, degree of 6 ionnization α) from concentration of lithium additive.  相似文献   

19.
From the Gibbs free energy and the equations of two-phase equilibrium curves of the two-dimensionalbinary system which has the Lennard-Jones potential, using the Collins model, the eutectic-type phase diagram and theperitectic-type phase diagram of the binary system are obtained, whose results are quite similar to the behavior of thethree-dimensional (3D) substances.  相似文献   

20.
It is generally assumed that in order to preserve Bose symmetry in the left- (or right-chiral) current it is necessary to equally distribute the chiral anomaly between the vectorial and the axial Ward identities, requiring the use of counterterms to restore consistency. In this work, we show how to calculate the quantum breaking of the left- and right-chiral currents in a way that allows to preserve Bose symmetry independently of the chiral anomaly, using the implicit regularization method.  相似文献   

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