Spatial variations in daily average CO2 concentrations above wetland surface of Xianghai National Nature Reserve, China

Horizontal and vertical variations of daily average CO2 concentration above the wetland surface were studied in Xianghai National Nature Reserve of China in August, 2000. The primary purpose was to study spatial distribution characteristics of CO2 concentration on the four levels of height(0.1 m, 0.6 m, 1.2 m and 2 m) and compare the differences of CO2 concentration under different land covers. Results showed that daily average CO2 concentration above wetland surface in Xianghai National Natural Reserve was lower than that above other wetlands in northeast China as well as the worldwide average, suggesting that Xianghai wetland absorbed CO2 in August and acted as“sink” of CO2. The horizontal variations on the four levels of height along the latitude were distinct, and had the changing tendency of“decreasing after increasing” with the increase of height. The areas with obvious variations were consistent on different levels of height,and those with the highest variations appeared above surface of shore, sloping field, Typha wetland and Phragmites wetland; the vertical variations were greatly different, with the higher variations in Phragmites wetland and Typha wetland, and the lands near the shore and the sloping field with the lower variations. Spatial variations of daily average CO2 concentrations above wet!and surface were affected by surface qualities and land covers.     

受污染地表水体生物修复技术研究进展

主要介绍了受污染地表水体生物修复技术的类型及特点,综述了国内外关于受污染地表水体生物修复技术研究及应用的现状,并对生物修复技术的研究及应用进行了展望.     

煤中部分潜在毒害微量元素在表生条件下的化学活动性

利用连续化学浸取实验方法，对采自贵州省二叠经龙潭组的３２个煤样中的１０种潜在毒害微量元素化学的活动性进行了研究，结果表明：煤中Ｈｇ、Ａｓ、Ｓｅ、Ｃｄ等元素具有极强的化学活动性，其中平均８３．８％的Ｈｇ、９３．５％的Ａｓ、８０．３％的Ｓｅ．６３．３％的Ｃ在．１％的Ｃｕ的８６．８％的Ｐｂ可以被带出煤中而进入表生环境；煤中Ｚｎ的化学活动性次之，只有平均４６．６％的Ｚｎ可能迁移进行环境中；Ｔｌ、Ｃｒ、Ｎｉ     

国际环境保护公约中技术转让障碍问题的探讨

随着世界各国对全球资源与环境问题认识的逐步提高 ,发展中国家必将签署越来越多的国际环境公约 ,参与到国际环境保护合作中。尽管许多国际环境公约都明确规定了发达国家在资金和技术上支持发展中国家保护环境履行国际公约的义务 ,但是实际履约过程中技术转让的问题并未得到良好的解决。论文将讨论国际环境公约履约中的技术转让障碍问题 ,并以中国履行《关于消耗臭氧层物质的蒙特利尔议定书》 ,实施臭氧层保护行动过程中所存在的实际问题为例 ,对国际环境公约履行中技术转让障碍的原因及其后果进行分析 ,最后对发展中国家所应采取的立场和对策提出建议。     

Heavy metal adsorption on the Le An River sediment —The adsorption model

In this study,the surface properties and adsorption properties of the Le An River sediment were modelled via surface complexation approach.The model parameters were determined based on the data of our potentiometric titration experiments and the metal adsorption experiments with the Le An River sediment samples.Consequently,the surface complexation models for the natural sediment,in our case the Le An River sediments,which can interpret the experimental data very well were successfully established.Three typical surface complexation models that is the constant capacitance model,the diffuse layer model and the triple layer model,were considered in this research.This work indicated that the consistency and the interdependency among model parameters together with the selection of the surface adsorbed species should be emphasized.     

考虑声散射的街道交通噪声预报模型

提出一种预报典型的两侧密集分布建筑物的城市街道交通噪声ＬＡ１０和ＬＡｅｑ声级的计算机仿真模型。模型依据一种修正的虚声源原理。它不仅考虑发生于建筑方面的镜象反射和表面吸收，而且考虑了由于墙面的粗糙性所引起的发生于有限尺寸建筑表面声散射的影响。与实测比较表明本模型可得出良好的预报结果。通过对散射强度加以变化可估计表面声散射对预报声级的影响。结果表明，即使在一个相当混响的场合，镜象反射声能对扩散反射声能     

可变电荷表面对磷的吸附与解吸动力学

研究了可变电荷表面为主的土壤对磷的吸附与解吸动力学。结果麦明,磷吸附和解吸动力学均可用修正的Elovich方程、双常数速率方程和分段拟合的抛物线扩散公式来表征。吸附和解吸过程均可分为快、慢两个反应阶段。磷吸附过程是一个扩散控制的不可逆过程.     

超细煤矸石矿粉作天然橡胶补强填充剂的性能研究

以煤矸石为原料，通过超细粉碎、表面改性等深度加工，制取了一种新的橡胶补强剂，并对煤矸石作补强剂影响因素进行初步的研究，实验表明它能够取代或部分取代炭黑用作天然橡胶的补强剂。     

顺城地区地表水污染防治对策

通过对顺城河北地区地表水环境现状特点及其污染状况的调查详细分析了各支流的纳污量,了解河北地区各支流对浑河主河道的“污染贡献”,运用科学的方法确定各功能水质目标,提出水污染总量、控制削减方案和治理方案。     

Impact of triazophos insecticide on paddy soil environment

ＩｎｔｒｏｄｕｃｔｉｏｎＲｉｃｅｉｓｔｈｅｓｔａｐｌｅｄｉｅｔａｒｏｕｎｄ 3 0 %ｏｆｔｈｅｗｏｒｌｄｐｏｐｕｌａｔｉｏｎａｎｄａｒｏｕｎｄ 60 %ｏｆｔｈｅＡｓｉａｎｐｏｐｕｌａｔｉｏｎ .Ｔｈｉｓｃｒｏｐｉｓｐｒｅｆｅｒｅｎｔｉａｌｌｙｏｒｇｅｎｅｒａｌｌｙｃｕｌｔｉｖａｔｅｄｕｎｄｅｒｓｕｂｍｅｒｇｅｄｓｏｉｌｃｏｎｄｉｔｉｏｎｓｆｏｒｒｅａｓｏｎｓｏｆｂｅｔｔｅｒｙｉｅｌｄｓａｎｄｔｏｐｏｇｒａｐｈｉｃａｌｓｉｔｕａｔｉｏｎｓ(Ｒｅｉｃｈａｒｄｔ,1 997) .Ｔｈｅｉｍｐｏｒｔａｎｃｅｏｆｓｏｉｌｍ…