南京河西地区岩土体剪切波速与土层深度的关系

南京河西地区是南京市重点开发的新市区,该区域工程地质条件相似,主要为长江高河漫滩地质地貌单元。本文选取该地区47个典型钻孔的岩土体剪切波速资料,采用三种数学模型进行统计回归分析,运用相关系数R(或测定系数R2)检验Vs—H之间的线性相关关系,并根据计算的SD值选择较优的数学模型。统计结果表明,该地区各类岩土体的Vs—H线性相关关系显著,说明采用上述数学模型进行Vs—H回归是可行的。对两个工程场地进行剪切波速预测,并对场地类别作出划分,检验结果表明,该地区各类岩土体的Vs—H经验关系是可靠的,符合当地岩土特征,在样本深度范围内有足够的工程应用精度,可以应用。     

泥石流坝后侵蚀坑纵剖面形态及最大深度实验研究

泥石流拦砂坝坝后侵蚀坑形态和深度是泥石流冲刷基础研究的薄弱环节。通过室内水槽实验,探讨了泥石流坝后侵蚀坑的形态和不同实验控制条件下侵蚀坑深度的变化规律等。由实验观察可知,侵蚀坑纵剖面整体上呈现两端浅中间深的形态特征,其最深点的位置随水槽坡度增大向下游方向发展;侵蚀坑坑内上游坡度较下游坡度陡,对于具有相同级配的粘性砂和无粘性砂,无粘性砂的侵蚀坑坑内坡度较粘性砂的缓;侵蚀坑的最大深度受沟床纵坡、泥石流的容重、沟床组成物质的性质(特征粒径、粘性)等因素的影响较大;泥砂粘性的存在将大大削弱侵蚀的深度。     

高危作业有害因素预防控制水平预警模型

针对职业卫生领域出现的急慢性职业病及突发性化学中毒等事件,本文采用预防控制水平指标体系,用因子分析法构建了单项有害因素的预警模型。在此基础上,利用加权平均法给出了多项有害因素的综合预警模型,其中,应用层次分析法确定各个有害因素的权重。高危作业有害因素预警模型的提出为高危作业有害因素防治提供了量化的科学依据。     

纳米铝粉对烟火药剂热安全性影响研究

为研究铝粉纳米化后对烟火药剂性能的影响,本文将普通铝粉和纳米铝粉分别与氯酸钾、硫粉按照零氧平衡的同一配比（17％AL＋63％KClO3＋20％S）配成的烟火药剂进行ARC热分析对比试验发现,含纳米铝粉的烟火药剂热分解的初始反应温度降低,反应到达最大温升速率所需的时间延长,反应所能达到的最高压力降低。这说明纳米铝粉的加入在加速其反应进程的同时,可有效地降低其反应的激烈程度和危险性,即铝粉纳米化后可以有效的改善烟火药剂的性能,提高其安全性。     

Modeling of air quality with a modified two-dimensional Eulerian model： A case study in the Pearl River Delta （PRD） region of China

A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta （PRD） region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols （SOA） concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^＋, SO4^2-, and SOA were calculated in the fine particle size range （〈2.5 μm）. The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign （IMC）. Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio.     

Spatial distribution of aerosol pollution based on MODIS data over Beijing, China

With the help of regression analysis,the relationships were detected between aerosol's contribution to apparent reflectance(ACR) derived from Moderate Resolution Imaging Spectroradiometer(MODIS)on board Terra and hourly PM_(10)mass concentration measured at 30 ground-based locations in Beijing for the August of 2003 and 2004.It was shown that there was a good correlation between the ACR and PM_(10)(linear correlation coefficient,R=0.56).On the basis of this relationship,spatial distribution and possible sources of PM_(10)derived from MODIS were analyzed and two frequently heavily-polluted regions were found,namely downtown of the city and the district near Xishan Mountain.These two regions coincidently are also urban heat island centers.The foundings of this paper will be greatly useful for environmental monitoring and urban planning for Beijing,especially for the 2008 Olympic game to be held in Beijing.     

Benchmarking Optical/Thermal Satellite Imagery for Estimating Evapotranspiration and Soil Moisture in Decision Support Tools

Generally, one expects evapotranspiration (ET) maps derived from optical/thermal Landsat and MODIS satellite imagery to improve decision support tools and lead to superior decisions regarding water resources management. However, there is lack of supportive evidence to accept or reject this expectation. We “benchmark” three existing hydrologic decision support tools with the following benchmarks: annual ET for the ET Toolbox developed by the United States Bureau of Reclamation, predicted rainfall‐runoff hydrographs for the Gridded Surface/Subsurface Hydrologic Analysis model developed by the U.S. Army Corps of Engineers, and the average annual groundwater recharge for the Distributed Parameter Watershed Model used by Daniel B. Stephens & Associates. The conclusion of this benchmark study is that the use of NASA/USGS optical/thermal satellite imagery can considerably improve hydrologic decision support tools compared to their traditional implementations. The benefits of improved decision making, resulting from more accurate results of hydrologic support systems using optical/thermal satellite imagery, should substantially exceed the costs for acquiring such imagery and implementing the remote sensing algorithms. In fact, the value of reduced error in estimating average annual groundwater recharge in the San Gabriel Mountains, California alone, in terms of value of water, may be as large as $1 billion, more than sufficient to pay for one new Landsat satellite.     

碱激发胶凝材料及其固化Pb^2＋的试验研究

对碱激胶凝材料（碱-偏高岭土、碱-矿渣和碱-粉煤灰）与水-水泥体系固化Ph^2＋进行了试验研究,其中水-水泥体系为对比样。结果表明：对于相同稠度的碱激发胶凝材料,即使Pb^2＋含量达到2．4％,除了碱-粉煤灰的抗压强度略低外,其他都达到30MPa以上,满足填埋或做建筑基材的使用要求;与水泥相比,碱激发胶凝材料能显著降低重金属离子（Ph^2＋）浸出浓度,其规律性与其NH4交换容量大小的规律性一致,与其固化体的抗压强度的大小没有相关性。     

Predictive models of turbidity and water depth in the Doñana marshes using Landsat TM and ETM+ images

We have used Landsat-5 TM and Landsat-7 ETM+ images together with simultaneous ground-truth data at sample points in the Doñana marshes to predict water turbidity and depth from band reflectance using Generalized Additive Models. We have point samples for 12 different dates simultaneous with 7 Landsat-5 and 5 Landsat-7 overpasses. The best model for water turbidity in the marsh explained 38% of variance in ground-truth data and included as predictors band 3 (630–690 nm), band 5 (1550–1750 nm) and the ratio between bands 1 (450–520 nm) and 4 (760–900 nm). Water turbidity is easier to predict for water bodies like the Guadalquivir River and artificial ponds that are deep and not affected by bottom soil reflectance and aquatic vegetation. For the latter, a simple model using band 3 reflectance explains 78.6% of the variance. Water depth is easier to predict than turbidity. The best model for water depth in the marsh explains 78% of the variance and includes as predictors band 1, band 5, the ratio between band 2 (520–600 nm) and band 4, and bottom soil reflectance in band 4 in September, when the marsh is dry. The water turbidity and water depth models have been developed in order to reconstruct historical changes in Doñana wetlands during the last 30 years using the Landsat satellite images time series.     

降解丙烯酰胺的活性污泥培养及驯化研究

采用阶梯式驯化法,控制温度在18℃～24℃,pH在6—8,溶解氧在4—8mg／L,在容积为6L的驯化器中对活性污泥进行培养驯化。经过25d的培养之后,得到了稳定降解丙烯酰胺的活性污泥。驯化后的活性污泥SVI为85—132,COD去除率达70％。