Diamond degradation in hadron fields

The energy dependence of the concentration of primary displacements induced by protons and pions in diamond has been calculated in the energy range 50 MeV - 50 GeV, in the frame of the Lindhard theory. The concentrations of primary displacements induced by protons and pions have completely different energy dependencies: the proton degradation is very important at low energies, and is higher than the pion one in the whole energy range investigated, with the exception of the delta33 resonance region. Diamond has been found, theoretically, to be one order of magnitude more resistant to proton and pion irradiation in respect to silicon.Comment: 7 pages, 3 figure

A study of charge collection processes on polycrystalline diamond detectors

Abstract We performed a study of charge collection distance (CCD) on medium to high-quality prototypes of diamond sensors prepared by Chemical Vapor Deposition (CVD). We studied the Charge Collection Efficiency in these materials supposing that it is limited by the presence of a recombination level and a distribution of trap levels centered at 1.7 eV from the band-edge. We also supposed that the exposition to ionizing radiation can make the trap levels ineffective (pumping effect). We have shown that these assumptions are valid by correlating the CCD to the pumping efficiency. Moreover, we have shown that the pumping efficiency is bias-dependent. We have explained our experimental results assuming that trapped carriers generate an electric field inside the diamond bulk

Hall effect measurements on proton-irradiated ROSE samples

Bulk samples obtained from two wafers of a silicon monocrystal material produced by Float-Zone refinement have been analyzed using the four-point probe method. One of the wafers comes from an oxygenated ingot; two sets of pure and oxygenated samples have been irradiated with 24 GeV/c protons in the fluence range from 10{sup 13} p/cm{sup 2} to 2x10{sup 14} p/cm{sup 2}. Van der Pauw resistivity and Hall coefficient have been measured before and after irradiation as a function of the temperature. A thermal treatment (30 minutes at 100C) has been performed to accelerate the reverse annealing effect in the irradiated silicon. The irradiated samples show the same exponential dependence of the resistivity and of the Hall coefficient on the temperature from 370K to 100K, corresponding to the presence of radiation-induced deep energy levels around 0.6-0.7eV in the silicon gap. The free carrier concentrations (n, p) have been evaluated in the investigated fluence range. The inversion of the conductivity type from n to p occurred respectively at 7x10{sup 13} p/cm{sup 2} and at 4x10{sup 13} p/cm{sup 2} before and after the annealing treatment, for both the two sets. Only slight differences have been detected between the pure and oxygenated samples

A Study of Marketing Strategy of Sony Electron in China

本文首先对索尼的企业创建、品牌成长、在华历程进行简要回顾。然后运用PEST、波特五力模型、SWOT分析法分析索尼电子在中国市场面临的宏观环境及所处的行业结构，揭示环境和行业结构对索尼电子带来的机会和挑战，分析索尼电子在中国营销的优势、劣势。在此基础上，以4P理论为视角，从产品、价格、渠道、促销四个方面对索尼在华营销策略进行了研究。研究发现，在产品策略方面，索尼注重以消费者需求为导向提供产品，在塑造品牌形象的同时不断加强售后服务网络的建设，以切实的行动维护消费者的利益，赢得了消费者的青睐；在价格策略方面，索尼主要采用了高价位的策略来提升产品定位，采用波浪式的降价来促销中等价位产品，结合中国市场的...The paper first makes a concise review of Sony’s history and its development in China. The paper then analyzes the macro environments and the industrial structure of Sony Electric in China by methods of PEST, Porter’s Five Forces Model and SWOT, to reveal opportunities and threats coming from the environments and the industrial structure, and analyzes Sony’s advantages and disadvantages in China’s...学位：文学硕士院系专业：新闻传播学院广告学系_传播学学号：3062007115249

PICTS analysis of extended defects in heavily irradiated silicon

We report the results of an experimental study on radiation-induced defects in silicon p/sup +/n diodes irradiated with 1-MeV neutrons up to a fluence of 2.3 /spl times/ 10/sup 15/ cm/sup -2/. Heavily irradiated silicon diodes have been studied by means of photo induced current transient spectroscopy (PICTS) technique using a variable filling time. For every filling time, a dominant broad and structured peak has been found in the temperature range 200-300 K. Such a broad peak cannot be accounted for by considering isolated point defects, being consistent with a quasi-continuous distribution of deep levels inside the bandgap. In addition, it is observed that the spectral lineshape tends to broaden as the filling time is increased. The details of the lineshape modifications depend strongly on the irradiation fluence of the sample, in such a way that they cannot be explained only in terms of emissions from noninteracting electron states. Thus we suggest that the investigated broad peak should, at least in part, be generated by emission from extended defects, also known as clusters

Theoretical calculations of the primary defects induced by pions and protons in SiC

In the present work, the bulk degradation of SiC in hadron (pion and proton) fields, in the energy range between 100 MeV and 10 GeV, is characterised theoretically by means of the concentration of primary defects per unit fluence. The results are compared to the similar ones corresponding to diamond, silicon and GaAs.Comment: 9 pages, 2 figures, in press to Nuclear Instruments and Methods in Physics Research A v2 - modified title, and major revision