火焰原子吸收光谱法测定锡基轴承合金中的铋

锡基轴承合金试样经盐酸、过氧化氢溶解,加入一定量的硫酸,以盐酸-氢溴酸排锡后,采用AAS法测定铋。对仪器条件、共存离子干扰进行了试验,方法测定B i的特征浓度为0.09μg/mL,相对标准偏差为3.23%和4.11%,加标回收率在95.64%~98.44%之间,满足锡基轴承合金中B i含量的测定。     

阳宗海、松华坝和云龙水库流域土地利用与水质变化

利用遥感(RS)和地理信息系统(GIS)技术,对阳宗海、松华坝及云龙水库流域1995年和2004年6种土地利用覆盖类型的遥感数据进行了制图及其叠加,通过对土地利用现状和变化情况的分析,并与库区的水质变化相结合,研究流域内土地利用结构及其变化与库区水质变化的关系。     

Applying global sensitivity analysis to the modelling of flow and water quality in sewers

While several approaches for global sensitivity analysis (GSA) have been proposed in literature, only few applications exist in urban drainage modelling. This contribution discusses two GSA methods applied to a sewer flow and sewer water quality model: Standardised Regression Coefficients (SRCs) using Monte-Carlo simulation as well as the Morris Screening method. For selected model variables we evaluate how the sensitivities are influenced by the choice of the rainfall event. The aims are to i) compare both methods concerning the similarity of results and their applicability, ii) discuss the implications for factor fixing (identifying non-influential parameters) and factor prioritisation (identifying important parameters) and iii) rank the important parameters for the investigated model. It was shown that both methods lead to similar results for the hydraulic model. Parameter interactions and non-linearity were identified for the water quality model and the parameter ranking differs between the methods. For the investigated model the results allow a sound choice of output variables and rainfall events in view of detailed uncertainty analysis or model calibration. We advocate the simultaneous use of both methods for a first model assessment as they allow answering both factor fixing and factor prioritisation at low computational cost.     

Microbial degradation and its influence on components of coalbed gases in Enhong syncline,China

Coalbed gases (CBG) in Enhong syncline are characterized by high concentration of C₂₊ (C_2–5), with the highest content of ethane over 30%. However, the concentrations of C₂₊ are not evenly distributed in the syncline. Based on the analysis of δ¹³C₁, δ¹³C₂, δ¹³C₃, δ¹³CO₂, δD_CH4 of CBG and their origin diagrams in the normal and abnormal areas, this research shows that gases in both areas are thermogenic gases and the reason for the uneven distribution of C₂₊ is that the microbial degradation action on gases is stronger in the normal area than in the abnormal area. The secondary biologic gases in the normal area are mainly characterized by that the carbon isotopes become obviously lighter in methane and become heavier in ethane, whereas the molecular and isotopic compositions of CO₂ change little. These features indicate that the secondary biologic gases are mainly generated by the microbial degradation of C₂₊, not generated by the reduction of CO₂. The degradation process is selective to make the residual ethane being enriched in ¹³C and the generated methane rich in ¹²C.     

区域CORS系统精度指标测试及分析

区域CORS建成后需要对系统的各项精度指标进行测试,其指标包括RTK测量精度、导航精度、覆盖范围、可靠性、稳定性、完备性等。为此,利用实测数据分析讨论了各项指标测试的过程和方法。     

水蒸气活化再生乙酸乙烯合成触媒载体活性炭

探讨了活化温度、活化时间、水蒸气流量对再生后活性炭吸附性能和得率的影响,得到了最佳工艺条件:活化温度1 000℃,活化时间60 min,水蒸气流量2.23 g/min。该工艺条件下再生活性炭的碘吸附值1 174.37 mg/g,亚甲基蓝吸附值200 mL/g,得率为62.87%。再生后活性炭的吸附指标达到国家一级品的标准,其中亚甲基蓝吸附值是国家一级品标准的2.22倍。同时,测定了该活性炭氮吸附,通过BET计算了活性炭的比表面积,通过密度函数理论(DFT)表征了活性炭的孔结构。结果表明:该活性炭为微孔型,BET比表面积为1 254.51 m2/g,总孔容为0.592 6 mL/g。     

顶空气相色谱法测定药品包装用复合膜、袋中溶剂残留量的不确定度评定

按YBB00182002要求,采用顶空气相色谱法测定聚酯/低密度聚乙烯药品包装用复合膜、袋中溶剂残留量,依据JJFl059-1999、CNAS-GL06,对测量结果不确定度进行系统分析,找出影响的主要因素;对各不确定度分量进行评定和量化,计算合成标准不确定度和扩展不确定度,测定结果表示为:(0.12±0.01)mg/m2,k=2。     

ZQZ—CY移动式自动气象站无线传输配置与实现

本文通过对ZQZ—CY移动式自动站GPRS模块进行参数配置及对中心服务站的设置,解决了移动式自动站的无线数据传输问题,实现了各移动自动气象站气象观测数据的远程统计、查询,以及相关的气象业务处理和数据应用分析。     

基于集对分析的云南省临沧市烤烟化学品质综合评价

采用集对分析法,考虑了等级标准边界的模糊性,避免了直接确定联系度中的不确定系数,对临沧市凤庆县、临翔区、永德县和云县2004年和2005年烤烟烟叶化学品质进行了综合评价;并将集对分析法与指数和法进行了比较.结果表明:总体上临沧烤烟化学品质较好,永德县烟叶化学品质等级最高,为最好的Ⅰ级,且年际间稳定,而其余3县(区)烟叶化学品质等级为Ⅰ～Ⅲ级,年际间较不稳定,应注重栽培技术和管理水平的提高;集对分析方法的评价结果较指数和法更合理,而且评价结果简明、直观.     

网格环境下的异构空间数据库集成技术

网格建立在服务的基础之上,使得空间数据库在网格环境中面临着如何提供相应的数据库服务、异构系统间的空间数据集成、空间数据如何进行互操作等问题。该文针对网格环境下异构空间数据库之间数据集成的困难,提出将OGSA-DAI中间件技术引入到空间数据库系统应用中,对OGSA-DAI进行空间数据访问的扩展,以实现异构空间数据库的有效集成,通过一个应用实例验证该方法的可行性。