Objective and quantitative evaluation of environmental quality of the land for agriculture purpose

An objective and quantitative evaluation method on land environmental quality for agricultural purpose in a county range is studied in this paper. The method takes into account the quantity of heat, precipitation, meteorological disaster and soil fertility, which have close relationship to the potential productivity of land and can be expressed conveniently and accurately by taking Kai County as an example. Besides comprehensive grading assessment, assessment with Hilbert Space distance coefficiency and comprehensive judgement by fuzzy sets theory, the assessment factors are expanded to 18 parameters, and fuzzy dominance matrix and fuzzy clustering methods are adopted for regional comprehensive identification of agriculture-use land. Among these methods, each benefits from association with the other. In this paper, an all-round and objective new way for understanding of land environmental quality is put forward.     

Ti(IV)与铜离子共掺杂的羟基磷灰石薄膜弱紫外光杀菌研究

采用共沉淀水热合成和离子交换的方法,制备了钛与铜离子共掺杂的羟基磷灰石(Ca10(PO4)6(OH)2:HAP)(HAPTiCu),以大肠杆菌为目标物,研究了不同材料负载的多孔镍网薄膜在弱紫外光下的杀菌活性.结果表明,HAPTiCu在弱紫外光下具有高效杀菌效率,并远远高于HAPTi和P25TiO2薄膜.这主要是铜离子的抗菌与光催化分解细菌的协同作用的结果.电子自旋共振(ESR)研究表明杀菌反应的主要活性物种是O-2·.HAPTiCu薄膜释放的铜离子在光催化杀菌反应过程中,被光催化还原沉积在表面,导致了较低的铜离子溶出,从而保证了材料的稳定性.     

环境监测管理的基本职能

以价值取向的观点,论述了环境监测管理在环境管理中的地位、作用和功能,提出了环境监测管理职能的核心是规划与控制,并依赖组织与协调职能的发挥,为环境保护的总目标服务。     

投资项目环境经济分析的几个问题

投资项目技术经济分析中环境经济分析是非常重要的一个方面，但目前由于经济核算统计指标的某些缺陷，使得项目环境效果与经济效果常常出现矛盾，相互间的转化也较困难，因此，在投资项目环境经济分析中出现了方法上的不足。本文对项目环境经济分析的现状进行了研究，提出了一些新的思路和方法。     

Simulated seasonal movement of precipitation zone in rainy season over China and its change on CO_2-doubling

In this paper, an investigation of simulated monthly precipitations from April to September is made. Though the precipitations are sometimes overestimated or underestimated, the geographical advance and recession of precipitation zones are well simulated by the UKMO global climate model with a simple mixed-layer ocean. Main characteristics of large-scale precipitation distribution are changed less on CO2-doubling, but the change is significant in some regions. The change in precipitation threatens us while the dry region is imposed by rainfall defect or the wet region by abundant rainfall induced by CO2-doubling.     

Determination of haloacetic acids in hospital effuent after chlorination by ion chromatography

The ion chromatography combined solid phase extraction (SPE) method was developed for the analysis of low concentration haloacetic acids (HAAs), a class of disinfection by-products formed from chlorination of hospital wastewater. The monitored HAAs included monochloroacetic acid, monobromoacetic acid, dichloroacetic acid, dibromoacetic acid and trichloroacetic acid. The method employed a sodium hydroxide eluent at a flow rate of 0.8 mlmin, electrolytically generated gradients, and suppressed conductivity detection. To analyze the HAAs in real hospital wastewater samples, C18 pretreatment cartridge was utilized to reduce samples' turbidity. Preconcentration with SPE and matrix elimination with treatment cartridges were investigated and found to be able to obtain acceptable detection limits. Linearity, repeatability and detection limits of the above method were evaluated. The detection limits of monobromoacetic acid and dibromoacetic acid were 2.61 μgL and 1.30 μgL, respectively, and the other three acids are ranging from 0.48 to 0.82 μgL under 25-fold preconcentration. When the above optimization procedure was applied to three hospital wastewater samples with different treatment processes in Tianjin, it was found that the dichloroacetic acid was the major compound, and the growth ratios of the HAAs after disinfection by sodium hypochlorite were 91.28%, 63.61% and 79.50%, respectively.     

表面活性剂强化重金属污染植物修复的可行性

表面活性剂因具有亲水亲脂的两亲性，已被广泛用来治理环境污染。利用表面活性剂强化植物萃取土壤重金属的可行性，是建立在表面活性剂、重金属、土壤、植物等四者之问的关系基础上的。文章根据乳化液膜分离、胶团强化超滤、金属液泡吸收等技术探讨了表面活性剂与重金属的关系。表面活性剂在其浓度超过临界胶束浓度时，在溶液中形成胶团，通过静电吸附与超滤，去除溶液中的重金属。超滤技术与ξ电位的试验结果确定了表面活性剂与土壤的关系，即土壤界面的吸附和金属缔合后，通过降低表面张力和增流作用解吸被吸附的金属。细胞膜透性学说揭示了表面活性剂与植物的关系．即表面活性剂改变生物膜的结构和透性，促使植物对重金属的吸收。开发环境友好性的生物表面活性剂是该研究领域的前沿方向。     

酸性水稻土有效硒提取剂的比较研究

采集12种肥力水平和含硒量差异较大的酸性土壤,连续两季(次)用盆栽方法种植水稻,测定植株含硒量(mgkg-1)、硒累积量(mg /盆)以及7种提取剂浸提的土壤硒量,检验两者间的相关程度。结果表明,0.1 molL-1 KH2PO4浸提土壤硒的操作简便,提取量较多,与植株含硒量间有极显著的相关性,适合作稻田土壤有效硒的提取剂;0.2 molL-1 K2SO4对土壤硒的浸提量低,与植株含硒量间的相关性不显著,不适宜作水稻土有效硒的提取剂。     

天目湖水环境现状及生态旅游可持续发展对策

天目湖是江苏省开发建设的重点旅游风景区之一，然而旅游业的蓬勃发展也造成了天目湖的水环境的巨大破坏。文章根据对天目湖的全湖周年水质观测以及相关的历史资料的分析，在阐述天目湖水环境现状、旅游资源的优势的基础上，提出天目湖生态旅游可持续发展的对策与建议：良好的水质是天目湖持续发展生态旅游的首要条件；明确划定天目湖水源保护区的范围；因地制宜发展具有地方特色的旅游产业；增强污水处理能力，实施截污工程；恢复植被，控制氮磷的入湖量；养殖业适度发展；加强生态旅游资源开发利用中的保护与管理。     

我国各地膨润土的水理特性

考察了我国各地膨润土的水理性质,讨论了膨润土的水理性质与层间阳离子的关系以及水理性质的矿床矿样间差异性,并对膨润土水理性质与其他物化性质间的相关性进行了分析。研究结果表明,膨润土因其属型和属性不同使其水理性质有较大的差异,其中层间阳离子类型是影响膨润土水理性质的重要因素,其中钠基膨润土具有高的胶质价、膨胀容和膨润值;不同矿床类型比较发现,沉积岩型矿样和火山沉积岩型矿样有较高的胶质价、膨胀容和膨润值;c轴有序度和<2 祄颗粒的质量分数与膨润土水理性质高度正相关。