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The global α -nucleus optical model is studied based on the nucleon self-energies in an Dirac-Brueckner-Hartree-Fock (DBHF) approach. The newly developed nucleon-nucleus optical model CTOM derived from DBHF, is used as the basis to consistently generate the real and imaginary potentials of the α -nucleus optical potential by double-folding model. The same range correction a of the improved local density approximation (ILDA) in CTOM is adopted, which is also suitable to modify the nucleon interaction range in α -nucleus systems. To get better description of experimental data, the re-normalization factors ( N R , N I ) are introduced in α -nucleus scattering calculations, and the individual optimized ( N R , N I ) for all nuclei and energies are searched out under the guidance of χ 2 criterion. We systematically explore the energy dependence of N R and N I by considering the α elastic scattering from 12 C to 208 Pb at incident energies below 120 MeV / nucleon and a simple exponential function is extracted. With this global α -nucleus optical potential, a reasonable description of all available experimental data for α scattering from nuclei is achieved.

Nickel aluminum matrix composites material reinforced with 10% volume fraction of -Al2O3 is prepared by exothermic sintering process. The reaction process and microstructures are analyzed by using differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results show that the activation energy of the sample with a volume fraction of 10% is 439kJ/mol. The reinforcements are -Al2O3 uniformly distributed in the NiAl matrix. The reaction occurs spontaneously at 1100K and emits a lot of heat.

A series of magnetic isothermal heat treatment of Alnico alloys (Alnico5 and Alnico8) in a 10 T magnetic field were performed. It was found that the high magnetic field strongly influences the modulated microstructure. Our observation shows that high magnetic field can enhances the nucleation rate of spinodal decomposition in Alnico5 alloy, leads the decomposed particles finer, and also increases the volume fraction of ferromagnetic particles. The external magnetic field ( H ext ) can also accelerate the atom diffusion and turn the diffusion direction to itself. The effect of both the E ext (the external magnetic field energy) and the E elast (the elastic energy) on modulated structure in a hypothetical A–B system was simulated by phase field method. The littler the E elast is, the bigger the E ext is, the decomposed ferromagnetic particles become smaller, and parallel along the direction of the external magnetic field.

The investment casting process offers great freedom of design with the economic advantage of near net shape production and has been widely used to process TiAl alloys. An investigation was undertaken to develop stable and cheap refractory slurry systems, suitable for use as a face coat in the investment casting of titanium aluminides. A TiO2–Al2O3 (TiAlO) based face coat slurry was investigated and compared with a traditional yttria based face coat slurry. After sintering, the chemical inertness of the manufactured shells in contact with molten TiAl alloys was tested by simulating the casting process using a flash re-melting test, in which sample shells were in contact with titanium aluminides at given temperatures for varying time durations and subsequently re-solidified. Compared with yttria, the TiAlO face coat had relatively lower chemical inertness against molten alloys, forming a thick hardened layer at the metal/shell interface with massive interaction products along grain boundaries. The reaction also changed the wetting behaviour of the TiAl on the TiAlO face coat with the contact angle decreasing as a function of interaction time.

We study the decays of the J / ψ and ψ ′ mesons to π + π − π 0 using data samples at both resonances collected with the BES III detector in 2009. We measure the corresponding branching fractions with unprecedented precision and provide mass spectra and Dalitz plots. The branching fraction for J / ψ → π + π − π 0 is determined to be ( 2.137 ± 0.004 ( stat. ) − 0.056 + 0.058 ( syst. ) − 0.026 + 0.027 ( norm. ) ) × 10 − 2 , and the branching fraction for ψ ′ → π + π − π 0 is measured as ( 2.14 ± 0.03 ( stat. ) − 0.07 + 0.08 ( syst. ) − 0.08 + 0.09 ( norm. ) ) × 10 − 4 . The J / ψ decay is found to be dominated by an intermediate ρ ( 770 ) state, whereas the ψ ′ decay is dominated by di-pion masses around 2.2 GeV/ c 2 , leading to strikingly different Dalitz distributions.

This paper will discuss the design and construction of BESIII, which is designed to study physics in the tau-charm energy region utilizing the new high luminosity BEPCII double ring e+e- collider. The expected performance will be given based on Monte Carlo simulations and results of cosmic ray and beam tests. In BESIII, tracking and momentum measurements for charged particles are made by a cylindrical multilayer drift chamber in a 1 T superconducting solenoid. Charged particles are identified with a time-of-flight system based on plastic scintillators in conjunction with dE/dx (energy loss per unit pathlength) measurements in the drift chamber. Energies of electromagnetic showers are measured by a CsI(Tl) crystal calorimeter located inside the solenoid magnet. Muons are identified by arrays of resistive plate chambers in the steel magnetic flux return. The level 1 trigger system, Data Acquisition system and the event filter system based on networked computers will also be described., 57 pages, 75 figures

Grinding fluid has an important effect in processing work piece, so in view of the new grinding fluid, a large number of tests have been taken in the application of the power ultrasonic vibration honing. The massive experimental study, separated from the work piece’s surface roughness, the work piece’s surface rubbed deterioration layer and the influence to the processing characteristic with different density of the new grinding fluid and so on, discussed the adaptability of the new grinding fluid in power ultrasonic vibration honing processing. The research has been indicated that although the new grinding fluid does not surpass the traditional working fluid, such as emulsion and liquor, in cooling performance, it has a better lubricating property and has the obvious superiority in the working accuracy and the oilstone’s length of life. Therefore the new self-developed grinding fluid is suitable for the power ultrasonic honing processing.

Seismic exploration in the conditions of complex surface topography in western China is a world-wide problem. A complex surface and weathering zone has a great influence on the results of seismic processing. The traditional rectangular grid finite difference method is difficult to adapt to the fluctuation of surface topography, but the difference method based on triangular grid can be used directly for forward modeling on models with complex top surfaces and migration without statics preprocessing. In this paper, we propose a layered irregular grid finite difference method, and apply it to acoustic wave finite difference pre-stack reverse-time migration. Tests on model data verify that the method introduced here can achieve perfect results in application.

Acidichromic and photochromic effects in alcoholic solutions of spiro(1,3,3-trimethylindolo-2,3′-naphth[1,2-b]-1,4-oxazine) are described. First-order, thermally-initiated decay kinetics associated with relaxation of the merocyanine form under acidic conditions are reported. A model for acidichromic and photochromic processes in these systems has been proposed. Preliminary results indicate that spirooxazine compounds are potentially useful in device applications such as pH sensors.

Local structure in a low-cobalt-type Fe–25Cr–12Co–1Si ferromagnetic alloy spinodal decomposed under an external magnetic field up to 120 kOe was investigated by Mossbauer spectrometry. The high magnetic field was found to significantly affect the local structure in the alloy formed at the early stage of phase decomposition. It was found that high magnetic field favors the acceleration of phase decomposition of ferromagnetic alloy at the early stage, resulting in the enhancement of average hyperfine field. The effect of high magnetic field on spinodal decomposition in ferromagnetic alloy was initially interpreted based on the free energy analyses.

This paper presents recent work on applications of spoiler control to aircraft manoeuvring enhancement and gust alleviation. The nonlinear inverse dynamics control technique is applied to the synthesis of a decoupled model-following flight control system for an aircraft with spoilers. The effectiveness of spoiler control on turbulence/gust alleviation is examined by some simulations of landing approach in turbulence.