In this paper, the mechanism of distortion and energy deposition at the interface of the particles in explosive consolidation of powders is analyzed. A one-dimension model of spherical symmetry is used to describe the closure of the micro-holes in powders. Effect of heat conduction is added to the one-dimensional flow equations of spherical symmetry, and the temperature distribution during the closure of the hollow sphere is solved by finite-difference under the condition that the material is rigid-plastic fluid and the constitutive equations are thermo-visco-plastic. The results show that effect of heat conduction becomes more remarkable when the scale of the holes become small; during the closure of the holes the state of the interior surface changes from elastic-plastic to fluid, and its temperature is much higher than other part of the spherical shell.

With finite-element software ANSYS 7.0 and simple thermal-mechanical coupling constitutive relations, the buckling failure of preloaded shell irradiated by high power laser beam was studied by numerical simulations. Buckling mode and buckling critical loading were analysed for different preloading conditions. The influences of laser intensity, beam irradiation time, preloading conditions, shape and geometric parameters of shell on the buckling mode were discussed. The numerical results showed that: (1) the buckling deformation of the shell was concentrated on the area of laser spot and the radial buckling was the main buckling mode, (2) a linear relationship between buckling eigenvalue and the maximum temperature at the center of laser spot was approached, (3) the buckling failure of shell was attributed to the coupling effect of the material softenning and the radial deformation in the laser spot, and hence to raise the stiffness of the material would enhance the ability of anti-irradiation of structure substantially, (4) the effect was more obvious under internal preloading for different shapes of shell, and the cylindrical shell had larger buckling eigenvalue and higher security.

A new method for the determination of interatomic separation-pressure relations is investigated and applied for alkali halides and MgO crystals. The method is developed by using Hildebrand approximation and an ionic model based on Harrison's treatment of overlap repulsive potential which takes into account the interactions up to second neighbors. The van der Waals dipole-dipole and dipole-quadrupole interactions calculated by more accurate methods are also included in the present work. It is found that the new method yield satisfactory results in agreement with the available experimental data.

A series of dynamic high pressure loadings to the organic macromolecular emulsion-nonyl phenol polyethyleneoxy ether (C₃₅H₆₄O₁₁) are carried out on a two-stage light gas gun. Within the shock pressure range of 11~42 GPa, seven Hugoniot data of the substance are obtained. The experimental results show that an inflexion is presented on the Hugoniot curve at about 17.8 GPa, which may indicate a complicated phase transition is happened at the high pressure and high temperature.

The interactions between the high-speed waterjet of 500 m/s and the condensed explosive have been simulated by LS-DYNA3D code with Lagrange method. The pressure distributions in the explosive at different times and the pressure histories at different elements of the explosive have been calculated. On the basis of numerical simulation, the sound speeds of the explosive have been determined. The numerical simulation results accord with the theoretical analysis. During the process of the interaction between the high-speed waterjet and the condensed explosive, the numerical simulation results show that the pressure decreases with the increase in the radial distance of the element and the maximum pressure occurs nearby or in front of the head of the penetrating waterjet.

The release isetropes of oxygen-free copper have been measured by explosive loading technique, in which brass is used as the flyer material, copper as the material both for baseplate and sample, and HR2-steel, SiO₂-heavyglass, LY12/LF6 Al, MB2 alloy, PMMA and air as the anvil materials. The results showed the measured release isentropes can be described through Grüneisen equation of state with constant ργ approximation in the initial releasing pressure range up to 219 GPa, and the relative deviation, (U_S-2u)/(2u), of the measured end particle velocity, U_S, with the value of the mirror-line approximation, 2u, increases with increasing initial releasing pressure.

In order to investigate the effects of ultra high pressure (UHP) on the content of soluble protein, peroxidase (POD) and pectinmethylesterase (PME) in litchi fruit, the pulp of litchi (Litchi chinensis Sonn cv. Huaizhi) was subjected to UHP treatment (100~400 MPa for 30 min at 10 ℃). The activities of POD and PME were detected by spectrophotometry, the isoenzymes of POD and PME were detected by native-PAGE and active staining. The content of soluble protein was detected by SDS-PAGE. Results showed that the POD activity raised and the new isoenzyme appeared when a treatment of 100~200 MPa was applied, the treatment of pressure 300~400 MPa made the POD activity decrease and the new isoenzyme disappear. The PME activity ascended and the new isoenzyme of PME appeared at 100 MPa; when the treatment of 200~400 MPa was applied the PME activity lowered and the new isoenzyme disappeared. The content of soluble protein had a little increase at 100 MPa, but continue to declined at 200~400 MPa.

The Dependence of the spectral distribution of photoemission from silver nano-particles embedded in BaO semiconductor thin film on temperature are predicted and investigated theoretically. At high temperature the photoemission response curves to wavelengths from 0.2 to 0.8 μm are given. It is showed that the higher temperature, the higher photoemission from silver nano-particles embedded in BaO. An explanation is also presented. It is also pointed out that the critical diameters of silver nano-particles between discrete electron eigenstates (quantum sizes region) and quasicontunuous energy bands for energy band of silver ultra-fine particles in the BaO are less than 3.8 nm

The geometry of propyl nitrate was fully optimized using the B3LYP method of density functional theory (DFT) and the standard 6-31G^* basis set. The bond dissociation energy of propyl nitrate was calculated. Calculations show that the weakest bond is O—NO₂ and the less weak bond is C—O. The pyrolysis mechanism of propyl nitrate was also discussed, and the products after the cleavage of O—NO₂ as well as C—O had been predicted. In addition, the heat of formation was calculated by ab initio, semi-empirical, and density functional methods, and the result of PM3 is in agreement with the experimental data.

The influence of H in using Li₃N as catalyst on the synthesis of cBN under high-temperature and high-pressure has been investigated. From the observation of cBN crystals growth within the sample capsule, the temperature gradient distribution has been discussed.