968 resultados para HIRFL-CSR


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环形加速器注入引出方法的研究对提高环内束流的强度、提高引出效率以及束流品质,具有重要的意义。本文对一些常用的环形加速器注入引出方法作了较为详细的研究,并着重对单圈注入、多圈注入与射频堆积以及束流冷却的有机结合作了理论研究和计算机模拟,从理论上实现了重离子束的快速累积。并建立了较完整的计算机程序,对这些多过程的结合进行了模拟,获得了与实验相符的结果。这一理论工作在国内尚属首次,在国际上重离子储存环领域中也是重要的新课题。 本文的研究重点是围绕兰州重离子加速器冷却储存环(HIRFL-CSR)注入引出系统的设计,对CSR主环的多圈注入、射频堆积等束流累积过程、主环的快引出和慢引出过程以及实验环的单圈注入过程进行了详细的计算机模拟,为CSR的束流累积、注入引出系统的工程设计提供了理论依据。

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气体探测器在核物理及粒子物理领域有着广泛的应用,尤其是阻性板室探测器,以其低廉的造价、优异的性能在各个大型实验室中都发挥着重要的作用。日本国家高能物理实验室(KEK)的Belle探测器,斯坦福大学斯坦福直线加速器中心(SLAC)的BaBar大型探测器,欧洲核子中心(CERN)的大型强子对撞机(LHC)的CMS与ATLAS谱仪,北京高能物理研究所(IHEP)的BESⅢ谱仪都使用阻性板室作为触发系统或缪子探测器。 随着HIRFL-CSR项目的完工。RIBLL2开展高能放射性束物理实验成为可能,而为了鉴别高能重离子碰撞实验中出射的高能轻粒子,有必要测量粒子的飞行时间(TOF)。为此,我们研制了单隙定时RPC,并作了简单性能测试。在CSR实验终端上,它可以作为传统塑料闪烁晶体+PMT时间探测器的替代,成为反应出射产物测量的大型探测器系统(4π)中的重要成员。 本论文对RPC的发展历史以及被广泛应用的原因做了深入而详细的研究,并对RPC的结构、性能、工作模式、特点、气体系统等进行了深入探讨。研制了一套单气隙RPC探测器样机,测设了一些相关性能,并对所遇到问题的产生原因以及解决方案进行了分析。为了测试RPC的需要,搭建了一套多组分工作气体配气系统,论文中还对包括质量流量计的选定,相关配件的选择,以及后期整个配气系统的组装与调试进行了详细描述

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CSR(cooling storage ring)按计划将于2005年底建成调束,届时从~(12)C到~(238)U的重离子将可以分别被加速到900和400MeV的能量。HIRFL(兰州重离子加速器Heavy Ion Research Facility in Lanzhou)将用作CSR的注入器。为了CSR的屏蔽设计,本文利用现有的实验数据计算了由于束流损失产生的中子及其能谱、角分布,同时也估算了屏蔽体外表面的中子剂量、环境中子剂量及天空返照中子剂量。在源项计算中使用了400MeV/u~(12)C+Cu反应的中子产额、能谱、角分布的实验数据。计算表明,CSR对环境剂量影响最大的是天空返照中子。

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HIRFL was upgraded from beginning 2000. Besides of researches on nuclear physics, atomic physics, irradiative material and biology, the cancer therapy by heavy ion and hadron physics are being developing. The injector system of SFC+SSC can provide all ions from proton to uranium with higher intensity. The Cooling Storage Ring (CSR) has accelerated beams successful. The ions C-12(6+), Ar-36(18+), Xe-129(27+) have been accelerated up 1000MeV/u, 235MeV/u with about 10(9)similar to 10(8) ions per spill respectively. The beam momentum dispersion was measured from 4x10(-3) to 2x10(-4) after cooling by the electron cooler or similar to 4x10(-4) after accelerated to 1000MeV/u without cooling. In order to improve the nuclear structure and heavy isotope research in SFC+SSC energy domain, A Wien filter was added in front of RIBLL and gas was filled in first section of RIBLL; a new spectrometry SHANS has being installed. Presently, there are two starting version experimental setups at CSR.

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HIRFL is an accelerator complex consisting of 3 accelerators, 2 radioactive beams lines, 1 storage rings and a number of experimental setups. The research activities at HIRFL cover the fields of radio-biology, material science, atomic physics, and nuclear physics. This report mainly concentrates on the experiments of nuclear physics with the existing and planned experimental setups such as SHANS, RIBLL1, ETF, CSRe, PISA and HPLUS at HIRFL.

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The convergence of corporate social responsibility and corporate governance has changed the mechanism of corporate accountability, which has developed "corporate self-regulation...

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New governance (NG) denotes a new approach in the governance strategies. This approach comes with a conceptual background explaining how the hardcore corporate decision-making and people-friendly business strategies have started to converge, relying on executive fiduciary duties, stakeholder engagement, and economic analysis of management incentives. It also addresses how companies incorporate stakeholder-friendly business strategies, examines the role of shareholder and board activism in pushing for social responsibility, and provides quantitative assessments of reporting practices, indexes, and ratings that link governance with responsibility (Kolk 2008; Statman 2005; Deegan 2002). It suggests models for pursuing this emerging frontier through greater involvement on behalf of the board of directors and utilizes a comparative approach to cross the border between the traditional ...

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CSR is increasingly an essential issue for business enterprises. It is a company and multidimensional organizational ...

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"Even though Corporate Social Responsibility (CSR) has become a widely accepted concept promoted by different stakeholders, business corporations' internal strategies, known as corporate self-regulation in most of the weak economies, respond poorly to this responsibility. Major laws relating to corporate regulation and responsibilities of these economies do not possess adequate ongoing influence to insist on corporate self-regulation to create a socially responsible corporate culture. This book describes how the laws relating to CSR could contribute to the inclusion of CSR principles at the core of the corporate self-regulation of these economies in general, without being intrusive in normal business practice. It formulates a meta-regulation approach to law, particularly by converging patterns of private ordering and state control in contemporary corporate law from the perspective of a weak economy. It proposes that this approach is suitable for alleviating regulators' limited access to information and expertise, inherent limitations of prescriptive rules, ensuring corporate commitment, and enhance the self-regulatory capacity of companies. This book describes various meta-regulation strategies for laws to link social values to economic incentives and disincentives, and to indirectly influence companies to incorporate CSR principles at the core of their self-regulation strategies. It investigates this phenomenon using Bangladesh as a case study."--publisher website

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"This book examines the growing trend of recognition and practices of CSR in private enterprises in developing countries. It identifies the challenges and deficiencies in these practices and proposes means for improvement. Based on a sound theoretical foundation, this book focusses on the case of Bangladesh and the ready-made garment industry to exemplify the described developments. After a brief introduction the book outlines the standards of Corporate Social Responsibility. It compares the trends in CSR practices both in developed and developing countries and then embarks on CSR practices in the private sector in Bangladesh to finally present a detailed analysis of CSR and its practices in the ready-made garment industry. The book not only compares developing countries with developed, but as well provides an assessment and analysis of different stages of CSR within the South Asian area."--published website