国家体育场大体积混凝土的裂缝控制

本文介绍了国家体育场大体积混凝土的裂缝控制技术。通过科研机构的温度应力计算及优化方案,利用60天强度评定标准,加大掺合料用量,以及推迟水化温峰时间,并通过精心设计和严格执行施工方案等技术措施。     

改进的逆合成孔径雷达相位基准选择方法

本文提出了以雷达回波相位信息为依据,选择逆合成孔径雷达运动补偿的相位基准的准则。利用外场实测数据,成功获得了真实波音飞机的雷达图像,证明了准则的优越性。     

氢化非晶硅场效应晶体管的特性研究

氢化非晶硅场效应晶体管的特性对环境因素较为敏感，如光照、温度和湿度等。文中介绍光照和退火引起的氢化非晶硅场效应晶体官场效应特性的变化，并探讨导致这种变化的原因。     

采用静电自组装技术在光纤上制备光学薄膜的研究

采用静电自组装技术在石英玻璃光纤和显微镜载玻片上制备了二氧化钛胶体与阴离子聚电解质PSS、二氧化硅胶体与阳离子聚电解质PDDA的复合薄膜，研究了薄膜的光反射性能，在光纤端面上交替沉积光学厚度为λ/4的PDDA/SiO2低折射率薄膜，可以获得λ/4多层反射膜，使样品表面的反射性能大大提高。     

多变量非线性问题计算机图示的数学模型及其应用

本文将三维空间中非线性问题计算机图示的方法推广到多维空间中非线性问题,导出了一般多变量非线性问题计算机图示的数学模型,从而为计算机图示多变量非线性问题,获得多变量非线性问题总体的,直观的形象,以方便地把握问题总体变化趋势,提供了工具.     

N.m.r. study of molecular dynamics in chemically crosslinked polyethylene

Results of measurements of the proton spin-lattice relaxation time T₁ in chemically crosslinked low-pressure polyethylene are presented. The dicumyl peroxide used for crosslinking changed the α-process dynamics without disturbing the β -process or the motion of the methyl groups. Classical relaxation processes (which are analogous to the case of pure polyethylene) have been observed for samples with 0.5–2.5 wt% crosslinking.     

Effect of the ingestion of an extract from Bauhinia monandra seeds on rats

Bauhinia monandra is a leguminous plant that would be used in human nutrition, however it shows a high hemagglutinating activity against trypsin-treated erythrocytes of rabbit, 2 ml of a NaCl-solution extract of the seeds was given to a group of rats for 10 days. Intestinal disaccharidase activity was determined. Histopathological and histochemical examinations were also performed. Lectins from Bauhinia monandra seeds did not cause any visible intestinal damage even when they seem to be able to bind to the enterocyte brush border. The low disaccharidase activity in the membrane and enterocyte fractions, which represent the enzyme synthesis level, indicates that lectins could reduce the synthesis of these enzymes rather than inhibit the active sites of the enzymes. This effect could be in turn related with the binding action of lectins, because no effect of the autoclaved extract on the disaccharidase activity was observed.     

Bio-Liquefaction/Solubilization of Lignitic Humic Acids by White-Rot Fungus (Phanerochaete chrysosporium)

Humic acid samples obtained from lignite were liquefied/solubilized by using white-rot fungus, and chemical characterization of the products was investigated by FTIR and GC-MS techniques. Prior to the microbial treatment, raw lignite was oxidized with hydrogen peroxide and nitric acid separately, and then humic acids were extracted by alkali solution. The prepared humic acid samples were placed on the agar surface of the fungus and liquid products formed by microbial affects were collected. The products were analyzed and the chemical properties were compared. The results show that oxidation agent and oxidation degree affect composition of the liquid products formed by microbial attack.     

探讨建筑设计中的两大问题

有人说建筑是文化的载体。一个优秀的建筑不仅要满足人们视觉感观和精神层面上的需求,还要追求其永恒价值,力争使其具有时代感和超前意识。作为建筑设计师不仅在建筑方案设计阶段要处理好美观与坚固、诗意与功能、节俭与安全、经济与节能等等诸多方面的问题,还要在建筑施工图设计阶段彻底解决这些问题。