应压木纤维素非晶区取向度的测定和分析

在以前用偏振荧光法测定正常材纤维素非晶区取向度的基础上，对马尾松材应压木应压区、对照区的取向度作了系统的测量，结果表明非晶区的取向度有一定分布规律，特别是早、晚材应压区的取向度均大于对照区，并对此作了初步的分析。     

流动含优面法──求解线性规划问题（LP）的一种快速算法

流动含优面法──求解线性规划问题（ＬＰ）的一种快速算法阮国桢主题词线性规划，基点，含优面分类号Ｏ２２１，１流动含优面法简介考虑线性规划问题ｍａｘｆ＝ｅｘ（ＬＤ）ｓ．ｔ。ＡｘＣｂ．ｘＭＯ其中ｃ，ｘ６Ｒ”，ｈＥＲ”，Ａ是ｍＸｎ矩阵．Ｘ一｛ｘ６Ｒ叫Ａｘ＜ｂ...     

动量表象下的Lorentz变换生成元

在动量表象下对非零质量带自旋粒子的角动量算符和推动矢量算符也即Lorentz变换生成元进行了讨论，得到了它们轨道和自旋两部分分拆的新的表达式。     

利用变换y=ze~(λx)讲解二阶常系数线性微分方程

施变换ｙ＝ｚｅαｘ于特征根为共轭复根α±ｉβ的常系数齐次线性微分方程ｙ″＋ｐｙ′＋ｑｙ＝０和施变换ｙ＝ｚｅλｘ于常系数非齐次线性微分方程ｙ″＋ｐｙ′＋ｑｙ＝ｅλｘ［Ｐｌ（ｘ）ｃｏｓωｘ＋Ｐｎ（ｘ）ｓｉｎωｘ］后，再设Ｚ※＝Ｑ（ｘ）ｃｏｓωｘ＋Ｒ（ｘ）ｓｉｎωｘ，解出齐次方程和导出非齐次方程的特解设置．     

Magnetic properties and giant magneto-impedance effect study of Fe-based nanocrystalline powder

The macroscopic and microscopic magnetic properties for amorphous and nanocrystalline Fe_73.5Cu₁Nb₃- Si1_3.5B₉ powder have been investigated and their giant magneto-impedance (GMI) effect is reported for the first time. The experimental results show that powder sample annealed at 510℃ possesses the optimum soft magnetic properties. However, the maximum longitudinally driven GMI (LDGMI) ratio (about 52%) is found in the sample annealed at 600℃. This means that the LDGMI ratio depends on not only their magnetic properties but also their electric properties.     

Protective effects of nitric oxide on salt stress-induced oxidative damage to wheat (Triticum aestivum L.) leaves

The changes of chlorophyll and malondialdehyde (MDA) contents, plasma membrane permeability confirmed that 0.1 and 1 mmol/L sodium nitroprusside (SNP), a donor of nitric oxide (NO) in vivo, could markedly alleviate the oxidative damage to wheat (Triticum aestivum L.) leaves induced by 150 and 300 mmol/L NaCl treatments, respectively. Further results proved that NO significantly enhanced the activities of Superoxide dismutase (SOD) and catalase (CAT), both of which separately contributed to the delay of O ₂ ⁻ and H₂O₂ accumulation in wheat leaves under salt stress. Meanwhile, the accumulation of proline was apparently accelerated. Therefore, these results suggested that NO could strongly protect wheat leaves from oxidative damage caused by salt stress.     

智能视听信息处理的新策略

综述了计算机听、视觉信息处理目前的研究状况及已取得的成果,并阐述了各国在信息处理领域的发展战略,结合＂超级智能视听信息处理系统的研究＂提出的集声、象、图、文计算机信息处理于一体的多信息处理系统研究的新思路,介绍了该研究的详细内容。指出该研究有可能开僻的一条新的信息处理途径。同时,指出智能化听、视觉信息处理技术将是多媒体计算机、多媒体通信乃至＂信息高速公路＂技术的基础。     

试论高校扩招形势下大学生就业压力的缓解对策

高校扩招是世界各国高等教育发展的必然趋势,它为经济发展提供了丰富的人才储备,增强了经济和社会发展的后劲,但高校扩招使大学毕业生数量在短期内增长过快,造成空前的就业压力,这是不可避免的。要缓解大学生就业压力,应从政府采取政策、措施宏观调控;高校保证教育质量、加强就业指导、就业推荐;全社会开辟多种就业渠道,形成就业市场调节就业;大学生积极自主就业等多方面相结合,多管齐下,形成合力,努力保持大学生就业形势的基本稳定。     

Born-Infeld方程解的表示

通过构造黎曼不变量,引入一些非线性变换和运用特征线法,给出了Born-Infeld方程一般解的显式表示.