单质硫改性介孔炭对水溶液中汞的吸附性能研究

对介孔炭CMK-3进行单质硫改性得到OMC-S,并通过静态吸附实验研究了该材料对水溶液中汞的吸附性能。研究结果表明：单质硫改性可以在介孔炭上负载12.33%的硫,从而使得介孔炭对汞的吸附容量从185 mg/g提高到476 mg/g;OMC-S具有较广的适用pH值范围,在pH 3～11.5范围内其对汞的吸附去除率均达到92%以上;氯离子对OMC-S的吸附性能具有一定的抑制作用,原因在于它能和汞离子络合形成一系列吸附性能较差的Hg-Cl络合物,而腐殖酸在所研究的范围内对OMC-S的吸附性能无明显影响。     

2007年5～8月云南省雷电活动特点和致灾因子分析

对2007年5～8月雷电活动及其灾害成因进行了分析,结果表明:云南雷电活动频繁,但空间分布不均匀;雷电活动的时间分布基本呈一峰一谷变化,峰值出现在17～18时,谷值出现在10～11时;雷击灾害发生的可能性不但与闪电频数有关,还与闪电强度有关,闪电一般发生在回波强度≥40 dBz、组合反射率≥45 dBz、回波顶高≥12 km的具有典型强对流特征的区域;回波强度越强、顶高越高,发生雷电的可能性越大,出现的雷电灾害越严重;低槽切变、两高辐合型北方系统以及南海低压、热带辐合带型、西行台风型南方热带系统为雷电的发生发展提供了有利的环流背景以及动力、热力或者水汽条件;雷电发生在SI<0℃和θse850-θse500>6℃的强烈对流不稳定区域内.     

Change of Flood Patterns in China under the Influences of Climate Change and Human Activities

Based on the flood affected area （FA） data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and human activities. The flood center shifted from North China and the Yangtze-Huaihe basin in the 1950s towards the south, north and west of China, and located in the south of the Yangtze River and South China after the 1990s. The FA in the western provinces was continuously on the rise since the 1950s. There are two characteristics for the future flood pattem in China. The pattern of ＂flood in the south and drought in the north＂ depends on the north-south shift of the maximum rainfall region in eastern China. The flood intensification to the west of Hu Huanyong＇s line mainly results from the increase of rainfall, extreme precipitation and the melting of glaciers under the background of human activity magnification.     

Distribution of heavy metals in agricultural soils near a petrochemical complex in Guangzhou, China

The aim of the study was to investigate influence of an industrialized environment on the accumulation of heavy metals in agricultural soils. Seventy soil samples collected from surface layers (0-20 cm) and horizons of five selected pedons in the vicinity area of petrochemical complex in Guangzhou, China were analyzed for Zn, Cu, Pb, Cd, Hg and As concentrations, the horizontal and vertical variation of these metals were studied and geographic information system (GIS)-based mapping techniques were applied to generate spatial distribution maps. The mean concentrations of these heavy metals in the topsoils did not exceed the maximum allowable concentrations in agricultural soil of China with the exception of Hg. Significant differences between land-use types showed that Cu, Pb, Cd, Hg and As concentrations in topsoils were strongly influenced by agricultural practices and soil management. Within a radius of 1,300 m there were no marked decreasing trends for these element concentrations (except for Zn) with the increase of distance from the complex boundary, which reflected little influence of petroleum air emission on soil heavy metal accumulation. Concentrations of Zn, Cu, Pb, Cd, Hg and As in the five pedons, particularly in cultivated vegetable field and orchard, decreased with soil depth, indicating these elements mainly originated from anthropogenic sources. GIS mapping was a useful tool for evaluating spatial variability of heavy metals in the affected soil. The spatial distribution maps allowed the identification of hot-spot areas with high metal concentration. Effective measures should be taken to avoid or minimize heavy metal further contamination of soils and to remediate the contaminated areas in order to prevent pollutants affecting human health through agricultural products.     

On the Food Disasters in the Lower Jingjiang Reaches: Grey Prediction Model and Application

In the light of the historical substantial data (covering a 70-year period) collected in the Lower Jingjiang segment and aided by topological grey method, here we attempt to characterize the occurrence and future trend of flood calamities in the study area. Our findings indicate that overall the high-frequent flood disasters with middle to lower damage prevail at present. A series of dramatic flood waves will appear in the years of 2016, 2022, 2030and 2042, particularly a destructive flood will occur between 2041 and 2045 in the Lower Jingjiang reaches. Typical of sensitive response to flood hazards in close association with its special geographical location, the lower Jingjiang segment hereby can reflect the development trend of floods in the middle Yangtze reaches. According to the results, a good fitness was revealed between the prediction and practical values. This actually hints that the topological grey method is an effective mathematical means of resolving problems containing uncertainty and indetermination, thus providing valuable information for the flood prediction in the middle Yangtze catchment.     

企业建立和实施环境目标、指标和管理方案中的问题及对策

分析了认证企业在建立环境目标、指标和管理方案中存在问题,提出了改进对策。     

宁波市公民防灾应急状况调查研究

为了解公民关于应急知识的掌握情况,也为制定应急宣传教育方法和重点教育内容提供依据,采用自编问卷对1 318名公民进行了调查。结果显示,宁波市公民防灾应急意识状况总体良好,但存在显著的性别差异、城乡差异、文化程度差异、年龄差异和职业状态差异。     

静电放电电磁辐射模式的建立与仿真

介绍了静电放电电磁辐射场的理论模型;针对长导体模型分析了其数学模型的建立方法;讨论了长导体模型实验仿真方法与结果.     

体育教学反馈与自我反馈运用的探讨

体育教学过程中,教学效果的好坏取决于师生双方对过程的调控程度,而对技能教学的调控,则依据教师的教学反馈和学生的自我反馈来实现。在体育教学过程中,教学反馈与自我反馈的有机结合,是提高教学质量的关键。