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991.
走滑式断层地震的折迭突变模型 总被引:1,自引:1,他引:0
利用过势函数微分形式的途径,计入远场外力功的影响,对走滑式断层地震机制进行分析.研究表明:突变理论中折迭突变模型展示的性状,与走滑式断层地震的主要特征之间一一对应.折迭突变可对包括震前、震后围岩-断层系统稳定性描述在内的断层失稳起、终点位置、断层失稳错距等作出描述.给出3种性状可相互印证的断层失稳围岩弹性能释放量图解.走滑式断层地震强度与围岩压力及围岩断层的刚度比等有关,围岩压力大、刚度比小、主切应力轴与发震断层面夹角大,则地震强度大. 相似文献
992.
993.
The spectra of Rydberg hydrogen atom in magnetic fields have been calculated using linear variational method with B-splines basis functions [Acta Phys. Sin. 55 (2006) 3380]. Based on these calculations we have done some statistics analysis about the high Rydberg energy levels. The nearest-neighbor energy spacing distribution and the 3-statistics have been shown about diamagnetic Rydberg hydrogen atom with the magnetic field being 0.6 T and 6 T. The phenomena of multiply crossing, multiply anti-crossing, and the mixed of crossing and anti-crossing of energy levels have appeared in this paper. For both cases, in range of lower energy, the energy 1evel statistics properties close to Poisson distribution. With the increasing of the energy, the energy level statistics properties are away to Poisson distribution and tend to Wigner distribution step by step. 相似文献
994.
Aditya M. Vora 《理论物理通讯》2010,54(1):159-166
Ashcroft's local empty core (EMC) model pseudopotential in the second-orderperturbation theory is used to study the electron dispersion relation, theFermi energy, and deviation in the Fermi energy from free electron value forthe liquid alkali metals and their equiatomic binary alloys for the firsttime. In the present computation, the use of pseudo-alloy-atom model (PAA)is proposed and found successful. The influence of the six different formsof the local field correction functions proposed by Hartree (H), Vashishta-Singwi (VS), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F), andSarkar et al. (S) on the aforesaid electronic properties is examined explicitly,which reflects the varying effects of screening. The depth of the negativehump in the electron dispersion of liquid alkalis decreases in the orderLi →K, except for Rb and Cs, it increases. The results of alloys are in predictive nature. 相似文献
995.
A Brownian microscopic heat engine with a particle hopping on a one-dimensional lattice driven by a discrete and periodic temperature field in a periodic sawtooth potential is investigated. In order to clarify the underlying physical pictures of the heat engine, the heat flow via the potential energy and the kinetic energy of the particles are considered simultaneously. Based on describing the jumps among the three states, the expressions of theefficiency and power output of the heat engine are derived analytically. The general performance characteristic curves are plotted by numerical calculation. It is found that the power output-efficiency curve is a loop-shaped one, which is similar to one for a real irreversible heat engine. The influence of the ratioof the temperature of the hot and cold reservoirs and the sawtooth potential on the maximum efficiency and power output is analyzed forsome given parameters. When the heat flows via the kinetic energy isneglected, the power output-efficiency curve is an open-shaped one,which is similar to one for an endroeversible heat engine. 相似文献
996.
997.
CdS thin films were prepared by chemical-bath-deposited method and the effect of tempera-ture and time on the properties of CdS thin films was studied. Independent of the deposited temperature, the growth was mainly controlled by the ion-by-ion growth mechanism at the beginning of the film deposition, then the cluster-by-cluster mechanism came to be domi-nant. The growth rate increased faster with the increasing of temperature until the thickness reached the limitation, then thickness instead become thinner. The scanning electron micro-scope results revealed that the morphology of the CdS film changed from pinholes to rough,inhomogeneous surface with increasing deposition time and deposition temperature. The X-ray diffraction results showed the film structure was a mixture of two phases: hexagonal and cubic, and it was very important to controll deposition time to the film's crystal phase. All films in depth of approximate 100 nm existed above 65% transmittance, the absorption edge became 〝red-shift〞 with temperature rising. At 60 and 70 oC, with 20 min deposited-time, the energy band gap was more than 2.42 eV and decreased with time, while at 80 and 90 oC, the energy band gap was less than 2.42 eV and increased little when the time changed from 10 min to 15 min at 80 oC. 相似文献
998.
应用密度泛函理论(DFT)反应能计算及最小能量路径分析研究了CO2在气相和电化学环境中于Cu(111)单晶表面的还原过程。气相中,CO2还原为碳氢化合物的反应路径可能为:CO2(g) + H* → COOH* → (CO +OH)* → CHO*;CHO + H* → CH2O* → (CH2 + O)*;CH2* + 2H* → CH4或2CH2* → C2H4。整个反应由CO2(g) + H* → COOH* → (CO +OH)*,(CO + H)* → CHO*和CH2O* → (CH2 + O)*等几个步骤联合控制。在-0.50V (vs RHE) 以正的电势下,CO2在Cu(111)表面电化学还原主要形成HCOO-和CO吸附物;随着电势逐渐负移,CO2加氢解离形成CO的反应越来越容易,CO成为主要产物;随电势进一步变负,形成碳氢化合物的趋势逐渐变强。与CO2的气相化学还原不同的是,电化学环境下CO质子化形成的CHO中间体倾向于解离形成CH,而在气相中CHO中间体则倾向于进一步质子化形成CH2O中间体。 相似文献
999.
用同位旋相关的量子分子动力学(IQMD)模型计算了入射能量在30~200 MeV/u内, 不同中质比的反应系统(76Zn+76Zn, 76Ge+76Ge,76Se+76Se和76Kr+76Kr)碰撞产生的原子核阻止和反应产物能谱。 发现原子核阻止和不同方向的动能比值有很强的关联性,且可以用垂直方向和平行方向的碎片总动能比值的平方根近似地代替原子核阻止,用来提取同位旋相关介质中的核子-核子碰撞截面的信息。在核反应实验中,很容易测量到该物理量, 它是一个较好的探针。 The collision of different neutron/proton ratio, intermediate mass reaction systems(76Zn+76Zn, 76Ge+76Ge,76Se+76Se and 76Kr+76Kr) at the beam energy of 30~200 MeV/u are studied by using isospin dependent quantum molecular dynamics(IQMD) model. It is found that there exists a strong relationship between nuclear stopping and the ratio of different direction kinetic energy, and nuclear stopping can be replaced by the square root of the ratio of perpendicular and parallel total kinetic energy of fragments, and it can be used to extract information of isospin dependent in medium nucleon nucleon cross section. This physical quantity can be easily measured in nuclear reaction experiments, and it is a better probe. 相似文献
1000.
在修改的Fisher模型框架下, 利用同质异位素产额比和结合能方程中对称能系数与温度比率的关联, 可以提取对称能系数与温度的比值。 利用3种不同的近似方法得到了重离子核反应产生丰中子余核的对称能系数与温度比(asym/T),并研究了相关物理量对asym/T的影响。结果表明, 库仑能对提取丰中子余核的asym/T影响较小,且参考核的选取对asym/T的提取也有一定的影响。 In the framework of the modified Fisher model, correlations between the symmetry energy coefficient in semi classical mass formula to temperature (asym/T) and the isobaric yield ratio in Heavy ion collisions are established. asym/Tof neutron rich fragments are extracted using these correlations. It is found that the Coulomb energy term has little effect on asym/T of fragments, while the reference isobars adopted have great influence on the extracted a sym/T of fragments. 相似文献