光敏器件及粘度自动测量仪

本文阐述了光敏器件在非电量测量中的重要作用。介绍了利用光敏器件胼配以其他电子技术研制成的粘度自动测试仪。该仪器测量精度较乌氏粘度计提高近一个数量级。文中给出了测量结果和应用实例。     

工程建设施工索赔管理

工程建设过程中,索赔与反索赔是经常发生的事情,正确的处理好该问题,对工程建设至关重要,做为工程建设的管理者,应切实做好这方面的工作。     

Simulation on Mechanical Behaviors of Oil-film Bearing Sleeve by Elastic Interference Fit

1 Introduction Under heavy load case ,the performances of sleeve and bush are of vital i mportance to ensure the safety andreliability of oil-fil mbearing[2]. To keyless sleeve by interference fit ,in addition to enough strength,stiffnessand adhesive force ,its other i mportant considerations are periodic set-up and dismount so as to ensure the safetyof bearing. Abnormal wear and adhesion damages are usually occurred by the status and level of stress in bothjoint sections . Hence ,stress and d…     

Histopathological lesions and toxicity in common carp (Cyprinus carpio L. 1758) induced by copper nanoparticles

Different types of metal oxide nanoparticles (NPs) have been suggested for various applications such as water treatment and construction of agricultural pesticides; however, there are concerns about the potential toxicity of these compounds for the nontarget organism especially aquatic organisms. The aims of this study were assessing toxicity and histopathological effects of copper oxide NPs (NPs‐CuO) on common carp (Cyprinus carpio) as a model organism. For this purpose 150 common carp with an average weight 7 ± 1 g were exposed to 0, 10, 20, 30, 40, 60, 80, 100, 150, and 200 mg/l of CuO‐NPs (10 treatment with three replicates) for 96 hrs. After 24, 48, 72, and 96 hrs exposures, mortality rates recorded and gill samples were collected. Statistical analysis showed significant differences in carp survival between control and treatment groups (p < 0.05); regression between fish mortality rate and NPs‐CuO concentration was also revealed (p < 0.01). The LC₅₀ 96h of NPs‐CuO for common carp was estimated as 124.9 mg/l in this study. Various tissue damages were observed in gill of treatments; such as, hypertrophy, hyperplasia, lamellar fusions, erythrocyte infiltration, epithelial lifting; also, there was significant correlation between intensity of tissue lesions and concentration of NPs‐CuO (p < 0.01). The findings of the present study demonstrate that sublethal concentration of NPs‐CuO can lead to serious tissue lesions. Whats more, concentrations above 30 ml/l of NPs‐CuO can lead to some clinical signs; such as skin darkening and death with open mouth as well as definite fish death.     

汶川大地震西安市中小学建筑的震害调查和分析

"5.12"汶川大地震对西安市的一些房屋造成了不同程度的震害,尤其是占有相当数量的中小学建筑的震害更值得关注;通过对西安市中小学建筑砌体结构房屋的震害调查,分析了此类建筑的震害特点和原因,提出了提高中小学建筑抗震性能的建议,对今后我国中小学建筑的设计和抗震加固具有重要的指导意义。     

基于GIS的露天矿爆破灾害影响范围分析

本文将GIS的空间分析功能应用于矿山爆破开采的环境影响评价过程,对矿山爆破开采过程中的爆破振动效应、爆破大气污染、爆破及采场运输过程中的噪声污染分别进行建模并分析其影响区域,得到影响区域的超标范围图,为矿山开采的环境影响评估提供决策支持。     

岩石与混凝土界面的损伤特性研究

利用声发射试验,研究了岩石与混凝土界面裂缝端的应力场,进而确定最早出现裂缝的时间,结合万能试验机测得的应力和应变全曲线进行了对比分析,并用渐进破坏原理分析了岩石与混凝土界面的损伤演化规律。     

自分离硅微通道的氧化

本文研究了自分离硅微通道(self lift-off silicon microchannels)的氧化问题。自分离是在特定的实验条件下,在完成电化学刻蚀后,硅微通道可以自动和衬底分离的一种新技术。研究发现,在使用传统的干氧-湿氧-干氧氧化化过程中,硅微通道出现了弯曲变形的现象。微通道越薄,其形变越大。通过使用较厚的硅微通道以及在干-湿-干氧化过程之前增加了干氧,以及先进行激光切割的步骤,改善和基本消除了弯曲变形的现象。     

基于地应力和二次损伤的预留光爆层爆破参数研究

对于地下开采,预留光爆层进行二次爆破可以保证巷道掘进面轮廓成形效果,减少围岩损伤。基于地应力、应力波和爆生气体等共同作用理论,对预留光爆层二次爆破进行参数优化。分析预留光爆层厚度对地应力重分布的影响以及二次应力对爆生裂纹扩展的影响,可知二次应力会抑制爆生裂纹扩展,且预留光爆层厚度与二次应力大小呈正相关;分析在不考虑损伤、考虑一次损伤和考虑二次损伤条件下,轴向不耦合系数及炮孔间距大小的变化,可知考虑损伤可以适当增大轴向不耦合系数和炮孔间距。以焦家金矿深部开采工程为背景,对比爆破参数优化前后爆破效果,可知在深部开采时考虑地应力和损伤,能提高半孔率和节约成本。研究结果为地下开采爆破标准化提供了理论依据。     

稀土羧酸配合物对塑料的光敏化特性及机理初探

“可环境消纳塑料”的研发有赖于“可环境消纳塑料助剂”的开发,陈庆华等发现采用羧酸稀土配合物作为光敏剂开发的“可环境消纳塑料”具有避光继续氧化降解功能,这是实现“可环境消纳塑料”在垃圾系统中与土壤同化的关键技术之一。因此,对羧酸稀土配合物进一步系统的研究与应用开发,及“可环境消纳塑料”的研发具有重要的意义。