Transformation of the salt-tolerant gene of<Emphasis Type="Italic">Avicennia marina</Emphasis> into tobacco plants and cultivation of salt-tolerant lines

Salt-tolerant gene, CSRG1, which was isolated from a kind of salt-tolerant mangroves, Avicennia marina, constructed the transgenic plasmid, pGAM189/CSRG1. CSRG1, GUS, Kmr and Hyg^r could be transferred into tobacco genome by the ameliorated leaf discs method of agro-bacterium-mediate transformation. Thirteen stable resistant lines were obtained when fifty transgenic explants were selected through 50 mg/L hygromycin and 150 mg/L kanamycin. Assessments of PCR amplification, Southern blot analysis and GUS histochemical staining showed that CSRG1 has been integrated into the genome of the eleven transgenic lines (frequency of transformation was 22%). Northern bolt analysis revealed that CSRG1 had expressed in transgenic lines. The assessments of salt-tolerant ability and photosyn-thetic rates indicated that the survival rate of the transgenic lines is 80%—90% and the transgenic lines could increase by 30%—40% in plant height, even when they were cultivated in MS medium containing 2% NaCl and the total seawater (salinity 24). It is supposed that the special physiologic metabolic pathway formed by the products of CSRG1 can really endow the tobacco plants with the high salt-tolerant ability, not only to Na^ stress, but also to the comprehensive stress of various ions.     

New Parallel Interference Cancellation Scheme for DS／CDMA Systems

This paper proposes a new multi-stage parallel interference cancellation scheme by modifying the conventional multi-stage parallel interference canceller (PIC). At each stage, it first converts the interference-cancelled outputs from previous stage into the a prior information, in terms of which the bit mean values are computed and the multi-access interferenee (MAI) for each user is evaluated, and then an interferenee cancellation is performed to obtain further interference suppression. To reduce the implementation complexity, wegive an approximation expression for bit mean value. The performance over AWGN channel is analyzed and compared to the conventional PIC. The user number K= 7 and spreading factor N= 13 are chosen as simulation parameters. The computer simulation results show that the proposed PIC has better performance than the conventional PIC both with 2 interference cancellation (IC) stages, at bit error rate of 10^-3 , for example, about 3 dB performance gain is obtained by using the proposed PIC. It is also shown that our proposed PIC with 1-stage is superior to the conventional PIC with 2-stage in performance, which is of practical value because PIC with fewer stages can bring about shorter processing delay.     

对北京市海淀区部分健身健美操习练者的社会学调查与分析

本文通过文献资料法。实地考察法，问卷调查法等方法采考察当前北京市健身健美操运动的实际情况，通过健身健美操参与者的社会学比较分析，了解其习得体验与心态，选择此项活动的原因及愿望，本文分析了当前的优势与不足，并为更好地开展健身健美操运动，提出如下建议：1．在中青年女性中重点加强健身健美操的宣传；2．健身服务机构尽量提供灵活机动的锻炼时间．采用科学有趣、针对性强的健美操进行辅导与教学；3．教练员在辅导过程中应尽可能为学员的社交创造条件．     

全面建设小康社会与人的全面发展

人的全面发展是共产主义的理想目标和本质规定，人的全面发展也是社会主义现代化建设的内在要求。把人的全面发展作为全面建设小康社会的根本目标是据此确立的。全面建设小康社会与人的全面发展是互为前提和基础、相互促进的关系。全面建设小康社会促进了人的全面发展；而促进人的全面发展又推动了全面推动小康社会进步。我们要在全面建设小康社会过程中，努力促进人的全面发展。     

PAN分子环化行为对纤维结构及性能的影响

预氧化阶段是链状聚丙烯腈(PAN)分子演变为耐热梯型结构的过程。文中借助IR,X ray及纤维应力形变关系初步探索了PAN纤维预氧化过程中晶区和非晶区分子的环化行为对纤维结构及性能的影响规律。结果表明,PAN纤维在预氧化初期的环化反应主要发生在纤维的非晶区,中后期反应则在晶区和非晶区进行。从预氧化过程中纤维强度及拉伸形变曲线变化规律认为PAN纤维早期的环化反应主要在分子内进行。     

L^p（T，∑，μ）（p≥1）型空间单位球面间的等距的表现和延拓

给出了L^p型空间单位球面间的满等距表现定理，推广了关于l^p型空间的相应定理．作为简单推论证明了相关的等距延拓定理．     

有限深抛物量子阱中的类氢杂质态

运用三参数变分法,研究了在垂直于生长方向的磁场作用下抛物量子阱中类氢杂质态的束缚能和1s→2p-态跃迁能.结果表明,束缚能和跃迁能随阱宽变化有一极大值;束缚能随磁场单调增加,而跃迁能随磁场的变化出现了极小值.     

塔里木盆地沙尘天气的气候特征

利用塔里木盆地周边28个气象站1961—2003年逐日地面观测资料,分析了沙尘天气 的空间分布特征和时间演变规律,在构建多元线性回归影响因子模型的基础上,探讨了气温 、地温日较差、气压、平均风速、降水量5个气候因子对沙尘天气的影响程度,建立了沙尘 指数。塔里木盆地沙尘天气有着明显的地域分布特征和季节变化,春季是高发期,沙尘日数 与气候因子季节变化的关系非常密切。沙尘日数年际变化呈明显的减少趋势,具有6～9 a的 振荡周期。3—9月盆地沙尘天气的主要影响因子依次是平均风速、降水量和地温日较差。春 季降水量占主导地位,6—9月平均风速占主导地位。选取各月对沙尘天气影响有意义的气候 因子建立了沙尘指数,它在时间序列上对沙尘天气有很好的反映,可用来做沙尘天气出现日 数的气候预测。     

Sialon/SiC复相材料的高温氧化行为

研究了以粘土直接合成Sialon/SiC复相材料的氧化行为,以及Sialon相含量、氧化温度和氧化时间对氧化过程的影响·结果表明,Sialon/SiC复相材料的氧化速度与温度成正比、与时间的平方根成正比·Sialon相的抗氧化性优于SiC相·这种材料的氧化反应是一种钝化反应,具有较好的抗氧化性,Sialon相含量的增加能提高材料的抗氧化性·     

对平面激波的数值研究

从数学分析的角度，定量地研究造成平面激波脱体的物理条件。将来流Mach数M1、壁面转折角δ以及激波角β所满足的函数关系式转换为代数方程，建立完整的平面激波激波角的数值计算方法，给出激波前后气流物理量的变化关系。