An improved thermometer(TIB) is proposed for intermediate-mass fragments via the difference between isobaric yield ratios.The residual free energy of three isobars is replaced by that of the binding energy.The measure...An improved thermometer(TIB) is proposed for intermediate-mass fragments via the difference between isobaric yield ratios.The residual free energy of three isobars is replaced by that of the binding energy.The measured fragments in the 140 A MeV ^(40,48) Ca +9Be(181Ta) and^(58,64) Ni +~9Be(^(181)Ta) reactions are analyzed to obtain T_(IB) ranging from 0.6 to 3.5 Me V.TIBis suggested to be a direct determination of temperature avoiding the fitting procedure.展开更多
The mass dependence of critical parameters for the liquid-gas phase transition and multiplicity of intermediate mass fragment in the heavy ion reaction is qualitatively explored under the framework of lattice gas mode...The mass dependence of critical parameters for the liquid-gas phase transition and multiplicity of intermediate mass fragment in the heavy ion reaction is qualitatively explored under the framework of lattice gas model.Some results are compared with experimental data.展开更多
中国经济已转向高质量发展阶段,对外贸易也应从"大进大出"转向"优进优出"。本文在扩展的Kee and Tang(2016)模型框架下,分析进口中间品质量对企业出口国内增加值率(DVAR)的静态影响和动态效应。静态条件下进口中间...中国经济已转向高质量发展阶段,对外贸易也应从"大进大出"转向"优进优出"。本文在扩展的Kee and Tang(2016)模型框架下,分析进口中间品质量对企业出口国内增加值率(DVAR)的静态影响和动态效应。静态条件下进口中间品质量与企业出口DVAR负相关,其通过自主创新产生"加成率效应"和"相对价格效应"动态改进企业出口DVAR。在此基础上,本文利用中国工业企业数据、海关数据和专利数据对理论假说进行了实证检验。结果表明:(1)进口中间品质量静态下与企业出口DVAR显著负相关,动态下全样本效应为负,一般贸易不显著,而加工贸易显著负相关;(2)研发行为对一般贸易进口中间品质量的动态影响具有调节效应,较高研发程度的企业该效应显著为正;(3)对影响渠道的检验发现,创新对企业出口DVAR作用的显著中介变量是加成率和相对价格;(4)进一步分析发现,更高显性比较优势、更低与技术前沿差距和更优省份市场化指数对创新活动具有明显正向调节效应。上述结论表明,推动进口政策由出口导向向创新导向升级是建设更高全球价值链地位下贸易强国的有效途径。展开更多
文摘An improved thermometer(TIB) is proposed for intermediate-mass fragments via the difference between isobaric yield ratios.The residual free energy of three isobars is replaced by that of the binding energy.The measured fragments in the 140 A MeV ^(40,48) Ca +9Be(181Ta) and^(58,64) Ni +~9Be(^(181)Ta) reactions are analyzed to obtain T_(IB) ranging from 0.6 to 3.5 Me V.TIBis suggested to be a direct determination of temperature avoiding the fitting procedure.
基金Supported by the National Natural Science Foundation for Distinguished Young Scholar under Grant No.19725521 National Natural Science Foundation under Grant No.19705021Science and Technology Development Foundation of shanghai under Grant No.97QA
文摘The mass dependence of critical parameters for the liquid-gas phase transition and multiplicity of intermediate mass fragment in the heavy ion reaction is qualitatively explored under the framework of lattice gas model.Some results are compared with experimental data.
文摘中国经济已转向高质量发展阶段,对外贸易也应从"大进大出"转向"优进优出"。本文在扩展的Kee and Tang(2016)模型框架下,分析进口中间品质量对企业出口国内增加值率(DVAR)的静态影响和动态效应。静态条件下进口中间品质量与企业出口DVAR负相关,其通过自主创新产生"加成率效应"和"相对价格效应"动态改进企业出口DVAR。在此基础上,本文利用中国工业企业数据、海关数据和专利数据对理论假说进行了实证检验。结果表明:(1)进口中间品质量静态下与企业出口DVAR显著负相关,动态下全样本效应为负,一般贸易不显著,而加工贸易显著负相关;(2)研发行为对一般贸易进口中间品质量的动态影响具有调节效应,较高研发程度的企业该效应显著为正;(3)对影响渠道的检验发现,创新对企业出口DVAR作用的显著中介变量是加成率和相对价格;(4)进一步分析发现,更高显性比较优势、更低与技术前沿差距和更优省份市场化指数对创新活动具有明显正向调节效应。上述结论表明,推动进口政策由出口导向向创新导向升级是建设更高全球价值链地位下贸易强国的有效途径。
