Results 1 - 10 of 22
Results 1 - 10 of 22. Search took: 0.016 seconds
|Sort by: date | relevance|
[en] Based on Hijing-1.37 simulations, event-wise mean-pt fluctuations in Au-Au collisions at √sNN=200 GeV are studied with graphical and numerical methods. This study shows that jets/minijets could represent a substantial source of mean-pt fluctuations, and jet quenching could reduce these fluctuations significantly. Mean-pt fluctuation measurements are a promising probe of correlation structure produced in the early stages of central Au-Au collisions at RHIC energies
[en] Based on interacting gluon model, leading particle rapidity distributions for 100 GeV p + Ag collisions are calculated and compared with experimental data. The results are in a good agreement with data when a more sophisticated collision geometry is used and the final fragmentation process is included
[en] Partonic effects on two-particle transverse momentum correlations are studied for Au + Au collisions at √SNN=130 GeV in the Monte Carlo model, AMPT. This study demonstrates that in these collisions partonic interactions contribute significantly to the correlations. Additionally, model calculations are compared with data of the two-particle transverse momentum correlations measured by the STAR Collaboration at RHIC, and it is found that AMPT with string melting can well reproduce the measured centrality dependence of the two-particle transverse momentum correlations in Au + Au collisions at √SNN=130 GeV. (authors)
[en] This paper introduced olfactory sensory neuron's whole-cell model with a concrete voltage-gated ionic channels and simulation. Though there are many models in olfactory sensory neuron and olfactory bulb, it remains uncertain how they express the logic of olfactory information processing. In this article, the olfactory neural network model is also introduced. This model specifies the connections among neural ensembles of the olfactory system. The simulation results of the neural network model are consistent with the observed olfactory biological characteristics such as 1/f-type power spectrum and oscillations.
[en] A mixture of the Ti–Al–Sn–Zr matrix powder and SiC particles was used as a raw powder to fabricate an in situ TiC and TiSi reinforced titanium matrix composites (TMCs) via low energy ball milling–cold press forming–argon-protected sintering. The effects of various content of SiCp on the microstructure, phase composition and high-temperature oxidation behavior of the composites at 750 °C and 850 °C were studied. XRD results show that the oxidation phases were mainly composed of TiO, AlO, SiO and α-Ti. According to the SEM images, the cross-sectional morphology of oxidation at 750 °C for 100 h shows that the oxide layer (20.00 μm) in the TMCs with 10.0 vol% SiCp after oxidation was denser and thinner and was 82.13% thinner than that of the matrix (98.00 μm). The parabolic rate constant (k) of the oxidized composites decreases with the increase of SiCp content at 750 °C and 850 °C. In particular, the composites with 10 vol% SiCp content have smaller k. All the results show that the addition of SiCp in TMCs can improve high-temperature oxidation resistance.
[en] To solve the wave functions and energies of the groundstate of H+2 ion an iteration procedure for N-dimensional potentials is applied. The iterative solutions are convergent nicely, which are comparable to earlier results based on variational methods. (general)
[en] A mixture of the Ti–Mo–Nb–Al–Si matrix powder and Carbon nanotubes (CNTs) particles were used as the raw powder to produce the in situ TiC reinforced titanium matrix composites (TMCs) via powder metallurgy. The effects of various contents of CNTs on the microstructure, phase composition and hot corrosion behavior of the composites were investigated. The results show that the corrosion mass gain of the composites with CNTs content of 1.0 wt% was the minimum (18.73 mg·cm−2), which was about 44.4% lighter than that of the matrix (33.70 mg·cm−2). XRD results show that the corrosion phases were mainly composed of TiO2, Al2O3, SiO2, Ti(SO4)2, NaTiO2 and TiS. According to the SEM results, the grain size of the as-sintered composites can be refined by adding CNTs. With the increase of CNTs content, the grain size became smaller and smaller. The cross-sectional morphology shows that the oxide layer of the composites with 1.0 wt% CNTs after corrosion was denser and thinner (21.44 μm). It was about 82.13% thinner than the oxide layer of the matrix (120.00 μm). All the results show that the TMCs with 1.0 wt% CNTs have better hot corrosion resistance. (paper)
[en] Aluminum matrix composites (AMCs) with SiCp volume fraction of 2.5% and 5% were prepared by ball milling, powder mixing-cold pressing, sintering and hot extrusion using 1 μm SiCp and 7000 series aluminum alloy powders. The phase analysis and microstructure observation of composite extruded materials were carried out by metallographic microscope, x-ray diffraction (XRD) and scanning electron microscopy(SEM). The main properties of the composites including density, electrical conductivity and compressive mechanical properties were tested. The results show that SiCp is uniformly distributed around the particles of aluminum matrix in the AMCs fabricated by Argon sintering-hot extrusion. And when the volume fraction of SiCp increases from 2.5% to 5%, the grain size of the composite becomes smaller and the dislocation strengthening increases with the increases of volume fraction of SiCp. Simultaneously, the density and densification of the composites decrease with the increase of the volume fraction of SiCp, and the densification of the composites after extrusion is above 98.5%. The hardness of the composites increases from 192.3 HV to 201.4 HV with the increase of volume fraction of SiCp. The electrical conductivity of the composites also decreases with the increase of the volume fraction of SiCp which may be due to the fact that SiCp is difficult to conduct and hinders the movement of free electrons in the matrix. The compressive strength improves with the increase of the volume fraction of SiCp. When the volume fraction of SiCp is increased from 2.5% to 5%, the compressive strength of the composite in the solution-aging state increases from 668.12 MPa to 683.94 MPa, but the fracture strain decreases from 10.57% to 8.4 %. (paper)
[en] Based on the Beckmann method, a new quantitative method for the study of multi-particle azimuthal correlations is proposed. Collisions of 1.2A GeV Ar + KC1 in the LBL steamer chamber are analyzed with this new method and the original Beckmann method, respectively. The experimental results have been compared with the Vlasov-Uehling-Uhlenbeck model predictions for different nuclear equations of state. Using the new method, the incompressibility of nuclear matter can be estimated
[en] An aluminum alloy (Al-10.22Zn-2.87mg-1.2Cu-0.213Zr) with self-designed composition was used as the experimental object. Melting and casting, homogenization annealing and extrusion were carried out in sequence. The microstructure and properties of high strength aluminum alloy in different directions under the state of extrusion-hot pressing-solution-aging were preliminarily studied through XRD, hardness, conductivity, tensile strength, elongation and intergranular corrosion of the alloy in different directions. The results show that after subjecting the aluminum alloy to deformation and solid solution processes, the grains in the alloy undergo recrystallization, and the recrystallization degree in the S direction and the T direction is obviously greater than that in the L direction. Recrystallization does not occur substantially in the L direction. Part of dislocations remained in the alloy after the solution process which is a necessary condition to ensure high strength of the alloy. The alloy has the best comprehensive properties in the L direction, with 749 MPa tensile strength, 6.4% elongation, and 151.71 m maximum intergranular corrosion depth. (paper)