云南某冶炼废渣堆渗滤液产生及其影响因素研究

渗滤液作为渣堆对周边水土的主要污染源,是污染场地原位风险管控的关键对象。云南某历史遗留冶炼废渣堆出现了渗滤液产生量少、空间分布位置有限的特殊现象。为研究该冶炼废渣堆渗滤液产生的控制条件和影响因素,基于详细勘察和野外现场调查试验结果,构建了渣体包气带水文地质概念模型,并结合HYDRUS软件分析了不同条件下渣体包气带的水分变化。结果表明：该厚层渣体包气带水分运移深度有限,正常降雨条件下该渣体产生渗滤液的临界深度为8.8 m;暴雨条件下熔炼渣相较于石膏渣和生活垃圾更易产生渗滤液;渣体包气带越厚、初始体积含水率越低、渣体物质组成及其结构越复杂、覆土层越厚的条件下,渣体越难产生渗滤液。该研究结果对我国类似冶炼废渣堆原位风险管控处置具有重要的参考价值。     

水中内分泌干扰物-壬基酚的去除研究进展

壬基酚是一种内分泌干扰物,主要来源于NPEO,能通过生物富集作用进入生物体内并造成危害。当前检测水样中壬基酚的主要方法是采用GC—MS,预处理采用固相萃取。研究表明自来水厂的常规处理工艺对于壬基酚的去除有限;而活性炭、有机蒙脱土吸附等物理方法,超声声化、电化学氧化、光分解等化学方法可有效降解水中的壬基酚。     

太湖CDOM紫外吸收特性及其分子量时空分布特征

基于2006年8月16日、2007年3月28日对太湖梅梁湾15个样点和2007年11~12月对全湖61个样点的有色溶解性有机物(CDOM)吸收系数观测数据,对CDOM分子量相对大小的时空差异及其影响因素进行了分析.结果表明,梅梁湾地区主要富集的是高分子量CDOM,而大太湖地区则较为复杂,北部地区主要是高分子量的CDOM占据主导地位;而在太湖东西部,主要是低分子量的CDOM;南太湖区域,高分子量的CDOM和低分子量的CDOM相对平衡.不同波长范围内CDOM吸收模型的斜率系数(S)值对CDOM的分子组成的敏感性具有一定的差异性,UVR最为敏感,其次是UV-A,再次为UV-B,UV-C最不敏感.梅梁湾CDOM主要影响因素是陆源,陆源影响的强度随季节的变化具有一定的差异,其中8月份最强,其次是3月份,最弱为11月份.     

Recent Evolution of Petroleum Exploration and Exploitation Agreements in Developing Countries: New Approaches to Introduce More Flexibility and Progressivity in the Contractual Terms

Over the last decade rather important changes have occurred in the legal and economic aspects of international petroleum agreements for exploration and exploitation. In the late nineteen seventies, as a consequence of the strong increase in oil prices, there was a general tightening of contractual terms and conditions. With the present oil market imbalance, characterized by sharp price falls, there is a tendency to ease the applicable contractual terms. In such a rapidly changing environment, the economic terms contained in a petroleum agreement should be properly designed to introduce a certain element of flexibility and progressivity in regard to the government take, without unduly complicating the fiscal package or discouraging potential investors. This is the present challenge for international petroleum negotiators.     

非耐短路变压器短路和过载保护试验的自动测试系统

针对变压器产品认证标准GB 19212.1(IEC 61558-1)中关于"短路和过载保护"的型式试验项目,研发了一套智能自动测试系统。对于两种类型的非耐短路变压器,即输入保护和输出保护类型,分别给出了系统软硬件配置和详细的测试操作流程。相比传统手动测试方式,该系统的应用可显著减少人员在线时间,同时降低人工测量环节的不确定度。     

Influences of Suspended Particles on the Runoff of Pesticides from an Agricultural Field at Askim, SE-Norway

Field and laboratory experiments were conducted to study the loss of particles from agricultural fields, and the role of suspended particles in carrying pesticides in surface runoff and drainage water. Propiconazole, a widely used fungicide was applied to experimental fields located at Askim, SE-Norway. Samples from surface runoff and drainage water were collected and analyzed for sediment mass, pesticides, particulate and dissolved organic carbon through a whole year. The surface soil and the runoff material were characterized by its particle size distribution, organic carbon content in size fractions and its ability to bind propiconazole. The results show that (1) particle runoff mostly occurred during the rainfall event shortly after harrowing in autumn. The highest particle concentration observed in the surface runoff water was 4600 mg l^–1, and in the drainage water 1130 mg l^–1; (2) the erosion of surface soil is size selective. The runoff sediment contained finer particle/aggregates rich in organic matter compared to its original surface soil; (3) the distribution coefficient (K _d) of propiconazole was significantly higher in the runoff sediment than in the parent soil. According to our calculation, particle-bound propiconazole can represent up to 23% of the total amount of propiconazole in a water sample with a sediment concentration of 7600 mg l^–1, which will significantly influence the transport behavior of the pesticide.     

Farmers as modern-day stewards and the rise of new rural citizenship in the battle over land use

A decade ago, scholars such as Michael Woods suggested that mobilisation in response to development in rural spaces was the result of a redefinition of relations between individuals, communities and the State. This remains true with the rural representing a contested site characterised by debates concerning food and fibre, water and energy security. With the recent deployment of new energy technologies in areas traditionally used for agricultural production, increased confrontation and resistance over land use has forged unlikely alliances between farmers, environmentalists and concerned others, ultimately leading to the rise of a new form of rural citizenship. In the Australian state of New South Wales (NSW) where resistance to burgeoning coal seam gas operations has become the customary response of many rural communities, environmentalists and concerned others are mobilising in support of farmers, who self-identify as modern-day stewards and are actively working to protect a resource hierarchy of water, land and soil against industries believed to be putting these at risk. Adopting a qualitative case-study approach, this paper examines how residents and supporters in the regional Shire of Narrabri in NSW have responded to what many see as competing land uses. We argue that values traditionally associated with stewardship and rurality are being revalorised by citizens to actively oppose the visions of the State, which seek to prioritise extractive development over other alternate futures. We contend that this rise in rural relations represents a significant shift in the notion of citizens as “inhabitants” and presents a new and enduring form of agency.     

MODELING NITROGEN UPTAKE AND POTENTIAL NITRATE LEACHING UNDER DIFFERENT IRRIGATION PROGRAMS IN NITROGEN-FERTILIZED TOMATO USING THE COMPUTER PROGRAM NLEAP

Readily available nitrogen (N) sources such as ammonium nitrate with excessive irrigation present a potential hazard for the environment. The computer program Nitrate Leaching and Economic Analysis Package (NLEAP) is a mechanistic model developed for rapid site-specific estimates of nitrate-nitrogen (NO₃-N) moving below the root zone in agricultural crops and potantial impacts of NO₃-N leaching into groundwater. In this study, the value of NLEAP was tested to simulate N uptake by crops and NO₃-N leaching parameters in large lysimeters under the tomato crop. Three seedlings of tomato variety of H-2274 (Lycopersicum esculentum L.) were transplanted into each lysimeter. N fertilizer at the rate of 140 kg N ha^–1 was sidedressed in two split applications, the first half as ammonium sulphate and the second half as ammonium nitrate. The lysimeters were irrigated based on programs of C 0.75, 1.00, 1.25 and 1.50, C referring to class A-Pan evaporation coefficients. Parameters such as leaching index (LI), annual leaching risk potential (ALRP), N available for leaching (NAL), amount of NO₃-N leached (NL) and amount of N taken up by the crops (NU) were estimated using the NLEAP computer model. To test the ability of model to simulate N uptake and NL, measured values were compared with simulated values. Significant correlations, R² = 0.92 and P < 0.03 for the first year and R² = 0.86 and P < 0.06 for the second year, were found between measured and simulated values for crop N consumption, indicating that the NLEAP model adequately described crop N uptake under the varied irrigation programs using an optimal N fertilization program for the experimental site. Significant correlations, R² = 0.96 and P < 0.01 for the first year and R² = 0.97 and P < 0.01 for the second year, were also found between measured and simulated values of NL, indicating that the NLEAP model also adequately predicted NL under the varied irrigation programs. Therefore, this computer model can be useful to estimate the NO₃-N moving beyond the root zone under conditions in which the present experiment was carried out. Also, the NLEAP-estimated NAL values and other parameters can also be used to improve N management practices and N fertilizer recommendations that will help to decrease the adverse effect of N fertilizer on groundwater quality and farm profitability.     

城市可持续发展评价的分指数及综合指数公式

在指标按特征分类的基础上，提出了城市可持续发展评价分类指标的分指数公式和多类别组合的综合指数公式。应用遗传算法对公式中的参数进行优化，得到简单而适用的城市可持续发展评价模型。模型应用于全国“七五”，“八五”可持续发展评价结果与实际分析结果一致。该模型具有可比性强，通用性好和简单，实用的特点。