物业管理前期介入的作用

随着物业管理的深入发展,物业管理总是在物业建成之后介入的状况已经不适应物业管理发展的需要.能否让物业管理提前介入物业建设,在物业开发项目未竣工前,直至规划设计阶段即开始介入,从物业管理的角度及早发现问题、解决问题,避免出现入住后的管理与使用难题,引起了人们的广泛关注.     

Restorable variation of cytoplasmic type of male sterile line in rice by in vitro culture

Rice male sterile (MS) lines, IR66707A and IR69700A, which possess the cytoplasm of Oryza perennis and O. glumaepatula respectively, belong to the cytoplasmic type. Their sterility could be maintained but not be restored. By somatic cell culture of these two MS lines, 47 somaclones with 465 R1 plants were obtained. All of the 465 R1 plants were sterile in the spring season in Guangzhou. According to the expression of the R1 plants and the level of similarity to their donor parents, they could be divided into three types. The plants of type Ⅰ were male sterile. The sterility of some somaclones of this type could be restored by the test crossing varieties or alternated to fertile by changes of some environmental conditions. The hybrid F1 of test cross from the MS somaclones in type Ⅰ was fertile while the hybrid F1 from the donor MS lines was still sterile. The R1 plants of type Ⅱ were similar to the donor parents and also male sterile. The hybrid F1 from all of the plants of type Ⅱ crossed to test variety were still sterile, so they did not possess restorability. For the somaclone of type Ⅲ, all of R1 plants were sterile in both male and female organs. No seed was set in both conditions of self and cross pollination. The fact that the restorable variants obtained in the cytoplasmic type of MS lines of rice by in vitro culture reported here should be the first sample in somaclonal variation in plant kingdom.     

压力传感器的选择与应用

从工程应用的角度阐述了如何选择和应用压力传感器 ,结论对生产实践有指导意义     

沁水煤田赵家窑勘探区瓦斯分布异常现象研究

探讨了沁水煤田赵家窑勘探区瓦斯分布异常现象产生的原因。瓦斯分布含量和浓度与断层的性质、褶皱的向北斜部位、煤层的顶板岩性和煤层的埋藏深度有关。对该区瓦斯分布异常现象的因果关系进行了研究。     

玉林城区及周边县市商品降价促销的调查报告

通过对玉林市零售企业进行的商品降价销售行为的问卷调查，分析玉林市的商品销售现状，并提出一些建议，希望能对企业的经营情况有积极的参考意义．     

“2003—2006”年高职高专类国家级精品课程”的计量分析

文章从区域分布、学校分布和学校排名等方面统计分析了2003-2006年评选出来的241门高职高专类“国家级精品课程“,发现这241门课程的区域分布差异较大,少数院校在这领域具有绝对的优势。     

低温诱导对组培川贝母胚状体成苗的影响

组培川贝母(Fritillaria Cirrhosa D.Don)的胚状体经低温处理不同的时间，随后转入无激素的MS培养基中培养，发现低温处理40d的胚状体成苗率最高．对过氧化物酶的活性及其电泳图谱的研究发现，在低温处理及随后的培养过程中，过氧化物酶的活性、表达量及谱带数(特别是B区酶带)已发生明显的变化．C区酶带的出现，是川贝母低温处理诱导胚状体成苗的一个重要因素．