Interval estimates for diatom-inferred lake pH histories

We investigate ordinary least-squares and Bayesian methods for constructing interval estimates for historical lake pH's inferred from diatom sediments. The Bayesian method explicitly models several forms of variability, including the sampling and classification variability of the diatom records, estimation variability, and measurement error in observed pH's. The two methods produce similar interval estimates, but the Bayesian model allows design recommendations to be made.     

硫沉积气藏产量递减模型研究

以往对高含硫气藏开发技术研究所需录取的资料在实际操作过程中难以得到。因此，针对井筒附近发生硫沉积的高含硫气藏，建立了硫沉积复合气藏产量递减数学模型，运用 Stefest 数值反演绘制了 Blasingame 产量递减曲线，并分析了硫沉积对气井产量递减规律的影响。结果表明：产量递减中期，硫沉积区含硫饱和度越高，无因次递减产量积分“导数”曲线下凹越深，当含硫饱和度增大到 0.5 时，积分“导数”曲线下凹至最深，积分“导数”达最小值；硫沉积半径越小，无因次递减产量平缓段出现的时间越早；产量递减后期，无因次递减产量积分与积分“导数”曲线晚期为一条斜率为–1 的直线，表现为调和递减。该方法比压力恢复试井法更具优越性，可为高含硫气藏的开发提供指导。     

雾滴空间分布的实验研究：雾滴空间分布的机理

本文对描述雾滴在空间的质量分布特性的参数ｑ〔１〕与Ｊ〔１〕随操作条件的变化规律进行了实验研究。基于液体单元的受力情况，对雾滴在空间的分布机理进行了分析讨论。     

压强和温度对薄膜折射率的影响模型

基于膜分子和气相分子在沉积时竞争的观点,得到压强和温度对薄膜折射率影响的理论模型.模型的研究表明,薄膜折射率随真空压强的增加而降低;并随沉积温度的增加而增加.在不同真空压强和不同沉积温度下制备了氧化锆薄膜,计算了样品的折射率,结果显示的规律和理论模型的规律基本一致.     

化学镀Ni-P合金性能的影响因素研究

本文从镀液配方、施镀温度以及镀层的后处理温度等方面考虑,研究它们在一定范围内的取值,及对镀层的硬度、摩擦磨损性能、耐蚀性的影响.试验结果证实影响甚微.这样,由于这些工艺条件的适当放宽,将会降低生产成本并给实际工作提供了方便.     

Development of the PEARLS model (Particulate Exposure from Ambient to Regional Lung by Subgroup) and use of Monte Carlo simulation to predict internal exposure to 2.5 in Toronto.

Air pollution is a current and growing concern for Canadians, and there is evidence that ambient levels that meet current exposure standards may be associated with mortality and morbidity in Toronto, Canada. Evaluating exposure is an important step in understanding the relationship between particulate matter (PM) exposure and health outcomes. This report describes the PEARLS model (Particulate Exposure from Ambient to Regional Lung by Subgroup), which predicts exposure distributions for 11 age-gender population subgroups in Toronto to PM2.5 (PM with a median aerodynamic diameter of 2.5 microm or less) using Monte Carlo simulation techniques. The model uses physiological and activity pattern characteristics of each subgroup to determine region-specific lung exposure to PM2.5, which is defined as the mass of PM2.5 deposited per unit time to each of five lung regions (two extrathoracic, bronchial, bronchiolar, and alveolar). The modeling results predict that children, toddlers, and infants have the broadest distributions of exposure, and the greatest chance of experiencing extreme exposures in the alveolar region of the lung. Importance analysis indicates that the most influential model variables are air exchange rate into indoor environments, time spent outdoors, and time spent at high activity levels. Additionally, a "critical point" was defined and introduced to the PEARLS to investigate the effects of possible threshold-pathogenic phenomena on subgroup exposure patterns. The analysis indicates that the subgroups initially predicted to be most highly exposed were likely to have the highest proportion of their population exposed above the critical point. Substantial exposures above the critical point were predicted in all subgroups for ambient concentrations of PM2.5 commonly observed in Toronto after continuous exposure of 24 hours or more.     

聚噻吩透明导电复合膜的研究

采用减压蒸溜，０℃低温气相淀积法在聚酯（ＰＥＴ）基材上合成了聚乙烯醇－聚噻吩（ＰＶＡ－ＰＴｈ），获得性能优良的透明导电聚合物复合膜。研究了ＦｅＣｌ３和ＰＶＡ浓度配比、反应压强、聚合温度和时间对透过率和导电率的影响。最优工艺条件：ＦｅＣｌ３８．０ｗｔ％，ＰＶＡ６．０ｗｔ％，压强３．３７×１０４Ｐａ，温度０℃，气相淀积聚合时间１０ｍｉｎ。５５０ｎｍ处膜的透过率Ｔｒ≥８０％，导电率ρ≥０．２ｓ·ｃｍ－１，膜厚约１μｍ。     

高含硫气井井筒硫沉积位置预测模型研究

高含硫气井在气体开采过程中,随着井筒温度压力的降低,硫微粒在气相中的溶解度逐渐减小,在达到临界饱和态后将从气相中析出,当井筒中硫析出位置处的气流速度小于微粒临界悬浮流速时,析出的硫微粒在井筒中沉积,堵塞气体的流动通道,从而导致气井产量降低,影响气井的产能和经济效益,严重时造成气井停产。将井筒压力温度分布预测模型与硫溶解度模型耦合,结合井筒中微粒临界悬浮流速模型建立了高含硫气井井筒硫沉积预测综合模型,并对L 井进行了实例分析。研究结果表明：高含硫气井产量降低至临界产量后,随着气井产量的降低,井筒中气流速度逐渐减小,硫沉积区域沿井筒向下逐渐增加。     

真空镀膜机的原理及维护

为了教师和学生们能够更加顺利地完成真空镀膜实验并且维护好实验设备,本文主要通过真空镀膜原理及构造的角度,论述了真空镀膜机的具体维护。     

新疆准噶尔盆地西缘白杨河扇形地边缘沉积分析

依据新疆地区西准噶尔山地白杨河中游山前冲洪积扇缘沉积物剖面,分析了第四纪中晚期扇缘沉积结构,对沉积环境尤其是与沉积相关的水动力条件进行了分析与探讨．研究表明,沉积物自上而下分为5个沉积阶段．全部11个样品中的5个样品具有双峰式粒度分布,其中一个样品为3峰式．主峰粒度位于2．5φ,次峰在-3．5φ,-2．5φ,第三峰位于4φ．主峰代表弱水动力环境,次峰代表强水动力环境,第三峰接近静水环境,属于扇缘湖相环境．样品粒度的多峰式特征是干旱区山前洪水对不同粒级颗粒的搬运及沉积,或洪水期后较弱的水流所搬运的细颗粒物质对洪流阶段较粗颗粒沉积的填隙．受山前地貌影响,洪水期后扇缘附近洼地积水是第三峰出现的地貌环境原因．