重庆村镇住宅热湿环境现状及评价

通过对重庆地区村镇住宅的实地调研和村镇典型住宅温湿度连续监测,获得了重庆地区村镇住宅的主要围护结构形式以及典型房屋2010年1～9月的室内热湿环境状况,并利用重庆地区自然通风适应性热舒适性评价模型进行了分析。结果表明：现有墙体热工性能最好的是180红砖内外水泥砂浆抹灰外贴瓷砖形式,测试房屋冬季室内最低温度为83℃,最高相对湿度为962%,夏季室内最高温度为344℃,最高相对湿度为99%。监测数据中相对湿度大于70%的时数占总测试时数的93%。住宅围护结构的冷热抵御能力和湿舒适湿卫生条件都很差。采暖季节室内达到舒适只有2 d,空调季节有58 d,村镇地区围护结构冬季保温要求比夏季隔热显得更为突出     

长江中下游河道与岸线演变特点

分析了长江中下游河道岸线变化的主要因素，它们分别是河岸崩塌，泥沙淤积及人类活动等，其中河岸崩塌是河道岸线演变的最主要原因。总的来说长江中下游干流河势是稳定的，但五个河段有各自演变特点和规律，其中宜昌－枝城段河道与河床比较稳定，岸线顺直，但葛洲坝和三峡水利枢纽建成后对河床的冲刷作用较大；荆江段是长江著名的河曲段，其冲淤变化较大；城陵矶至湖口段为节点和分汊河床组成，一般来说节点较为稳定，而分汊河床不太稳定，湖口至江阴河段岸线一般较为稳定，但弯道河床变化较大；河口段不但受江流作用影响，还受潮流与波浪等共同影响，所以河口河床演变迅速，主要表现为汊道主泓迁移摆动。     

大气污染排放窗口机制研究

以2种典型的污染排放源(点污染源和线污染源)为基础,提出排污窗口的概念,通过参数转换分解源强对污染扩散进行研究。首先在高斯污染扩散模型的基础上,对非持续性污染源强建模,然后以某烟囱的周期性排污分析,检验排污窗口设置的合理性。对于单双号限行的窗口性质的污染排放研究中,首先对交通流建立线污染扩散模型,然后融合元胞自动机(9元胞互影响)模拟区域多角度污染的扩散平衡,最后对"单双号限行"下北京市不同区域空气质量指标进行分析与仿真。分析结果表明,合理的排污窗口能够减轻污染程度及对人们日常生活的影响。     

三峡库区大农业的自然环境现状与预警分析

根据系统序化的观点，分析了库区大农业主要环境因子的具有代表性指标的数量和警式线，并进行了对比，发现它们都处地逆向演替或退化之中。这对三峡水库和库区大农业均十分有害。说明库区大农业的环境恶劣或恶化，应处于警式状态之中。其主要原因是长期向自然过度索取，以牺牲环境为代价，发展人口和物质的生产。建议进一步研究大农业及其环境的调控；把对环境的逐步补救和防止新的破坏结合起来，开展新的生态建设工程。     

AQUIFER PARAMETERS FROM CONSTANT DRAWDOWN NONSTEADY-LEAKY TYPE CURVES1

ABSTRACT: A drain function and set of type curves were defined for the mathematical solution that represents one-dimensional flow under nonsteady conditions in a leaky aquifer for the constant drawdown boundary condition. A match point procedure was developed for determining the aquifer parameters transmissivity, storage coefficient, and leakance based on the drain function and type curves. Use of the procedure is illustrated by an example that utilizes simulated aquifer drawdowns and flowrate data. The drain function and type curves developed in this investigation include the effects of leakage for the constant drawdown boundary condition, which is not included in the existing drain function and type curve found in the literature. Thus, a new set of type curves was developed that can be used to analyze drawdowns for one-dimensional flow in a leaky aquifer with constant drawdown at a line sink. Applications would include flow to a canal or river, drainage of agricultural lands, and dewatering associated with strip mining operations.     

板料弯曲变形应力的滑移线解法

滑移线法作为一种求解塑性成形应力状态的常用方法而被广泛应用。而在板材弯曲中一般采用主应力法求解变形区的应力状态。通过对板料弯曲变形区应力分析 ,根据滑移线理论 ,推导出了变形区的应力分布规律 ,与主应力法求解的结果相同     

环境样品中痕量铅的流动注射在线分离及分光光度检测

1　IntroductionLeadiswellknownasoneofthemosttoxicmetalsandnotedinthefieldofenvironmentalchemistry[1 ] .Theleadconcentrationinnaturalwaterisextremelylow (sub μg·l-1 level)sothatsomepreconcentrationstepmustbeincludedtoassurethesensitivityofaconventionalin…     

A closer look at detectability

Environmental and Ecological Statistics - The theory underlying line transect and variable circular plot surveys—distance sampling—begins with an assumed detectability function, giving...     

Conditional and unconditional estimators of population size

Estimators for the population sizes of animal species are similar to Horvitz-Thompson estimators — they involve dividing counts of detected animals by the probabilities of detection. Knowing detection probabilities for different subpopulations allows one to estimate each sub-population size with such an estimator, and to add the results for an estimator of the total population. In the case where the proportions of animals belonging to the different sub-populations are also known, this paper shows that using those proportions to arrive at a common average detection probability will, when used in conjunction with the total number of animals detected, result in a better estimator. We provide two examples where the inferior estimator may seem sensible.     

水稻抗虫转基因光温敏核不育系植株的获得

以质粒pCUBAC-HPT作抗虫基因供体，优良光温敏核不育系612S为受体，采用基因枪转化法，获得了转抗虫基因sck和sbk的植株．分子证据表明，外源基因己整合到受体基因组中．蛋白活性测定和Western blotting结果显示，转基因在受体植株中得到表达．田间抗虫性测定表明，外源基因的转入提高了受体的抗虫性．本文还讨论了转基因技术在水稻育种中的作用．图5表2参12