基于移动互联网的城乡体育教学资源共享路径研究—以云南省为例

移动互联网的快速发展,可以充分利用数字化实现城乡体育教学资源共享.运用查阅文献、实践归纳对云南城乡体育教学资源现状分析,研究城乡体育教学资源共享的意义,探基于移动互联网对城乡体育教学资源的模式与策略,促进城乡体育教学资源均衡发展.     

The degradation mechanism of an AIGaN/GaN high electron mobility transistor under step-stress

Step-stress experiments are performed in this paper to investigate the degradation mechanism of an AIGaN/GaN high electron mobility transistor （HEMT）. It is found that the stress current shows a recoverable decrease during each voltage step and there is a critical voltage beyond which the stress current starts to increase sharply in our experiments. We postulate that defects may be randomly induced within the A1GaN barrier by the high electric field during each voltage step. But once the critical voltage is reached, the trap concentration will increase sharply due to the inverse piezoelectric effect. A leakage path may be introduced by excessive defect, and this may result in the permanent degradation of the A1GaN/GaN HEMT.     

“虚拟子公司”过程绩效监控的机制设计分析

企业集团打破子公司“绩效黑箱”的方式是建立绩效监控机制,而“虚拟子公司”是一种类子公司模式,一般不涉及直接的现金流管理,被视为集团的成本中心,建立过程绩效监控机制的重心不同于被视为利润中心的法人子公司.本文归纳了虚拟子公司的运行特点,以预算与绩效合同为基础,建立信息不对称环境下的动态博弈模型,提出企业集团对虚拟子公司进行过程绩效监控的机制设计要点.研究发现:只有总部对子公司的预算松弛度、绩效违约的惩罚系数、子公司经营层的努力成本和总部在监控系统上的投入等多种因素相互协调时,才能建立有效的绩效监控机制.     

利用活体成像技术研究海茸β-1,3/1,6-葡聚糖在小鼠体内的分布

以海茸β-1,3/1,6-葡聚糖(DAG)为研究对象,首先经还原胺化反应在DAG还原端引入功能氨基,再将其与N-羟基丁二酰亚胺(NHS)活化的荧光染料(Cy7)偶联,获得Cy7标记的DAG分子;利用小动物活体成像技术研究了DAG在小鼠体内的分布.结果表明,DAG在小鼠体内主要分布于肺、肝和肾,具有靶向小鼠肺部和通过肾排泄的特点.该方法简便、数据可靠,为多糖和寡糖的体内分布与代谢研究提供了参考.     

藤质家具出口区域贸易潜力分析

本文介绍了与藤质家具贸易潜力相关的研究动态,分析了中国藤质家具的出口现状,运用贸易引力模型对中国藤质家具出口贸易潜力进行了测算与分析。结论显示,中国藤质家具出口贸易流量主要与贸易伙伴国的人口、是否为发达国家两个因素有关,并均与贸易流量成正比。同时,从整体来看,2012年中国藤质家具出口对发达国家或地区存在过度贸易,而对发展中国家存在贸易不足。     

莫纳干演绎的“美国梦”

问及汤姆·莫纳干对那些经历挫折的生意人有什么忠告时，他答道：“你决不能放弃，继续前进。一次又一次地制定计划。如果必要，也可以在幻想中寻求慰藉。不过，在你制定出计划之后，就要设法去达到目标。”     

Influence of surface states on deep level transient spectroscopy in AlGaN/GaN heterostructure

Deep level transient spectroscopy(DLTS) as a method to investigate deep traps in AlGaN/GaN heterostructure or high electron mobility transistors(HEMTs) has been widely utilized.The DLTS measurements under different bias conditions are carried out in this paper.Two hole-like traps with active energies of E_v + 0.47 eV,and E_v + 0.10 eV are observed,which are related to surface states.The electron traps with active energies of E_c-0.56 eV are located in the channel,those with E_c-0.33 eV and E_c-0.88 eV are located in the AlGaN layer.The presence of surface states has a strong influence on the detection of electron traps,especially when the electron traps are low in density.The DLTS signal peak height of the electron trap is reduced and even disappears due to the presence of plentiful surface state.