Population biology of bryozoans: correlates of sessile,colonial life histories in freshwater habitats

Bryozoans are common, often abundant, sessile, colonial invertebrates of freshwaters. By reviewing what is known of their general ecology and considering in further detail the population biology of specific groups, we provide evidence that 1) populations are locally ephemeral and regional persistence is attained via a dynamic equilibrium between dispersal and colonization, and 2) sex may often be infrequent and a high degree of clonality obtains at both local and regional scales. On the basis of these characteristics we discuss how the group offers exceptional opportunities for investigating a number of fundamentally important ecological and evolutionary questions.The highly curious modification of the Molluscan type which the Polyzoa [=Bryozoa] present... the great beauty of their forms, and the facility with which they can in general be observed in a living state, cannot but render them special favorites for every lover of Nature; and for the more profound student must confer on them a peculiar significance, and invest their study with a scientific interest which is scarcely surpassed by that of any other group of animals.... (Allman 1856)     

微型实验在无机化学实验中的应用

阐述了微型实验在无机化学实验中的重要性,研究了微型化学实验技术在无机化学实验教学中的应用,并取得了一定效果。     

换热器试验台用制冷剂循环供应系统的研究

介绍了换热器试验台用制冷剂循环供应系统的研究背景,工作过程和技术特点．它攻克了普通制冷压缩机用于有高技术要求的综合性能试验台所无法解决的难题,为空调器用换热器综合性能试验台的研制,奠定了基础．     

X2105柴油机连杆轴承故障的理论分析和振动实验研究

通过计算和试验分析了利用测量发动机连杆轴承处缸体振动来研究连杆轴承因间隙而引起的振动特性．从而由发动机缸体表面振动特性判定发动机连杆轴承的故障．     

Effects of atmospheric pollution on human health

Most air pollutants do not lead to specific diseases. Depending on the pollutant, the concentration and the duration of exposure, some organs are more affected than others. The most frequent disorders are those caused by irritant gases and particulates on the mucous membranes and respiratory organs. The consequences are eye, nose and throat inflammations, diminished lung function, increased susceptability to respiratory infection and a higher incidence of chronic bronchitis. These disorders and diseases are, of course, influenced by other factors as well, such as immune deficiency, allergies, occupational exposure to pollutants, and particularly smoking. The effects of air pollutants are, therefore, multifactorially conditioned and nonspecific disorders are placed in the foreground. Evidence for an association of air pollution with adverse effects on human health is drawn from three sources: animal experiments, experimental human exposures, and epidemiologic studies of exposed human populations. The burden of atmospheric pollution must be reduced to protect human health by an adequate safety margin. In particular, the increased sensitivity of sick and aged people as well as children should be taken into account. In defining the maximum emmission levels, preventive aspects should have priority so as to keep the risk of damage to health and the harmful influences on the environment to a minimum.This article Effects of atmospheric pollution on human health by H. U. Wanner is a revised version of the same article that was first published in the Proceedings of the 1990 European Aerosol Conference; special issue of the J. Aerosol Sci., Vol. 21, Suppl. 1 (1990) 389–396.Reprinted with kind permission from Pergamon Press Ltd, Headington Hill Hall, Oxford OX3 0BW, Great Britain.     

青藏高原油菜蜂花粉中黄酮类物质的提取与开发的实验设计

本文根据作者从事的青藏高原油菜蜂花粉中黄酮类物质的提取和开发应用的研究，探讨了综合实验的设计，把科学研究引入到实验教学中，将会极大地促进高校的实验教学改革．     

亚铁法处理大型高炉煤气洗涤水中氰化物的实验研究

采用亚铁法处理高炉煤气洗涤水，并用正交实验设计方法设计实验。根据正交实验结果分析和单因素实验得出：硫酸亚铁可以有效除去高炉煤气洗涤水中的氰化物；最佳反应条件为：T=30℃，pH=6，α=3．5，t，=40min，td=35min；影响因素顺序为：r〉α〉pH〉td〉tr。     

莠去津在填充土柱中的运移

用土柱实验模拟莠去津在土壤中的运移、实验结果表明相当浓度的莠去津被淋溶到土柱的底部，说明莠去津对地下水存在很大威胁、应用CXTFIT的平衡与非平衡模型模拟莠去津在土柱中的运移，模拟结果表明CXTFIT的非平衡模型能很好地模拟莠去津的穿透曲线．由CXTFIT率定得到的莠去津在土柱实验中的吸附和降解参数和从批次实验得到的吸附和降解参数有较好的一致性．     

氧化态锰相互转化的实验教学研究

针对锰的氧化态多样、颜色变化丰富的特点，引导学生重点对锰（Ⅵ）和锰（Ⅲ）的生成与歧化反应的转化条件进行了试验，对试剂用量、反应温度、溶液pH值等影响反应方向与现象的因素进行了探讨，并对研究性实验教学问题浅述见解。     

台风Utor登陆广东过程的数值研究

台风Utor(0104)于2001年7月6日00时(UTC,下同)在广东汕尾地区登陆,带来比较严重的灾害性天气.以美国国家大气研究中心和宾州大学联合研制的第五代中尺度模式(MM5)为基础设计的台风预报模式比较准确地预报出台风Utor(0104)的移动路径(前24 h的移动路径平均误差为 68 km)和天气现象的分布.在此基础上,设计了3个敏感性试验:①是把华南地区(26°N以南,110°E以东)的陆地变为海洋,②是把华南地区的山地变为平地,③是减小华南地区陆地的粗糙度,即取为近似于静风的洋面上的值.对比数值试验的结果表明:引起台风登陆后减弱的最主要因子是下垫面水汽供应的切断,其次是下垫面粗糙度(摩擦)的影响;地形作用能使迎风坡的降水明显增加,但对台风强度则没有明显的影响.