少数民族文献的现状探析

民族文献是民族文化的重要组成部分,是民族文化得以传承的重要载体,它为地方社会、经济的发展提供丰富的信息资源。探析民族文献的现状,对保护、整理、研究民族文献、促进民族地区开发、发展将起着重要作用．     

南昌市高校公体学生课外体育活动调查研究

针对南昌市所在高校公体学生,课外体育活动开展现状进行调查分析。采用文献调查法、问卷调查法、访谈调查法,数理统计法等,分析课外体育活动开展现状,揭示存在的不足之处。提出完善举措,为今后一段时间内高校公体学生课外体育活动开展提供参考依据。     

水利工程风险损失概率分布模型分析

在水利工程风险估计过程中,选择的风险损失概率模型是否合适,将直接关系到水利工程风险估计结论的好坏,进而影响到风险管理者决策的质量.因此,本文采用建立模型和实例分析相结合的方法,根据水利工程风险事故历史资料对工程风险损失描述的详尽程度,主要分析了水利工程风险损失概率的两种模型:“损失概率曲线拟合”模型和“补空——理论概率...     

长白山火山区放射状水系分形特征研究

水系分维反映了水系的发育程度,体现了河道的复杂程度.以TM遥感数据和分形几何理论为基础,应用图像分析软件ENVI对长白山火山区水系进行了盒维数计算,经统计分析得到了该区四个子区域水系及整个区域水系的分维数.结果表明:长白山火山区水系分维数西部最大D=1.425,东部最小D=1.212;四个分区分维数的差异直接反映了其流...     

微波提取流动注射分光光度法测定纺织品中的甲醛

研究了微波提取流动注射乙酰乙酸甲酯分光光度法测定纺织品中的甲醛,并与传统的乙酰丙酮光度法进行了对比.该方法简单快速,灵敏度高,适合纺织品中甲醛的检测.在进行纺织样品处理时研究了微波萃取条件,并与水萃取和水蒸气蒸馏的提取方法进行了对比,结果显示,微波萃取法提取样品中的甲醛快速、高效,提取率可以达到98.67%.     

二次离子质谱进展

指出了二次离子质谱技术在材料表面分析方面有着广泛的应用,随着探测方法的改进,此技术也得到了迅速发展.在北京大学2×1.7MV串列静电加速器实验室,利用加速器飞行时间二次离子质谱装置对碳基材料进行了分析,通过实验观察到碳纳米管材料对氢具有很强的吸附能力,证实了理论上对此材料储氢能力的预言.     

Ｃｏｐｙｒｉｇｈｔ与Ｃｏｐｙｌｅｆｔ的经济学分析

Copyleft是一种全新的知识产权理念,它将知识产品的权利对外开放,对传统的版权（Copyright）制度提出了挑战,引起人们的广泛关注。通过从经济学角度对Copyright及Copyleft制度进行了比较分析,认为Copyleft满足了网络社会知识集体生产的需求,是对Copyright的超越与补充;两者都是人们在利益最大化原则下对知识产品产权形式的理性选择,并将长期共存。     

进口贸易如何促进经济增长——基于江西省全要素生产率的实证研究

本文利用1996-2005年的江西贸易统计数据,实证考察了1996-2005年间的进口对江西经济增长的促进作用,研究结果表明：进口对江西经济增长有着重要的推动作用。基于不同种类商品的进口增长率对全要素生产率的影响的分析视角,测度了进口贸易对经济增长的贡献,进口总体上通过提高全要素生产率促进了经济增长;初级产品的进口对全要素生产率的增长没有显著影响,但非食用原料和矿物燃料、润滑油及有关原料的进口有显著影响;工业制成品进口对全要素生产率的增长有显著影响。     

Capacity analysis of high-rank line-of-sight MIMO channels

Matrix perturbation theory is utilized to investigate high-rank line of sight multiple input multiple output channels in a microwave relay system. The upper and lower bounds of channel capacity are derived based on space time block codes technique and singular values decomposition. A useful constraint for designing LOS MIMO channels is developed by the use of the condition number of the MIMO channel matrix. The theoretical analysis of channel capacity is confirmed by the simulation. The results show that the proposed method is able to give a physical explanation of the high-rank LOS MIMO channel matrix characteristics.     

Molecular regulation of development and differentiation inStreptomyces

Development and differentiation is an important and leading research field in modem biology. Streptomyces has a complicated life cycle of morphological differentiation including the spore germination, aerial mycelium and spore formation. Each developmental stage has a distinguished morphological feature which greatly facilitates the identification of developmental mutants, the complementary cloning and the spatial and temporal expression of the genes involved in differentiation. This characteristic of Streptomyces  is comparatively superior to other prokaryotic bacteria such as Escherichia coli, Bacillus subtilis and Myxococcus xanthus. Moreover, Streptomyces  also possesses a complicated physiological differentiation in which it produces a wide variety of secondary metabolites (more than half of the 12 000 or so known antibiotics), including many important antibiotics used in medicine, agriculture and industry. Studies on the molecular mechanism of antibiotic biosynthesis will be helpful in improving the antibiotic producer and developing some new medicines. In comparison with eukaryotic microorganism such as Asperillus nidulans,the structure of genetic material in Streptomyces  is simple,and it is linear and conkaryotes such as Streptomyces  cerevisiae. The large number of genes are the molecular basis of Streptomyces  differentiation,suggesting that the regulation mechanism of gene expression in differentiation and development may be complex^[1]