生态环境监测的关键问题研究

生态监测是生态建设的基础和技术支持。本文主要从生态类型的划分；生态监测指标的建立；生态监测方法的选择；生态监测仪器的选型以及监测方法的推广执行；生态监测数据处理、监测网络建设；生态监测年报编制等几个方面进行探讨，以冀为生监测的开展提供思路。     

Hydrolytic dynamics of pesticide N''-(2,4-dimethylphenyl) -N-methylformamidine in aquatic solution

ＨｙｄｒｏｌｙｔｉｃｄｙｎａｍｉｃｓｏｆｐｅｓｔｉｃｉｄｅＮ＇－（２，４－ｄｉｍｅｔｈｙｌｐｈｅｎｙｌ）－Ｎ－ｍｅｔｈｙｌｆｏｒｍａｍｉｄｉｎｅｉｎａｑｕａｔｉｃｓｏｌｕｔｉｏｎ￥ＭｏＨａｎｈｏｎｇ；ＹａｎｇＫｅｗｕ；ＡｎＦｅｎｇｃｈｕｎ；ＬｉｕＹｅ...     

应用GEM法对硫酸工业中重金属污染的研究

为查明硫酸工业中主要重金属的危害以及不同制酸工艺产生的危害差异，对辽宁省主要生产硫酸企业进行了调研，并应用ＭＥＧ法，对矿石原料中重金属的含量进行了数学模型分析．     

Web开发中使用数据库连结池技术

数据库连接池的基本思想就是为数据库连接建立一个"缓冲池".预先在缓冲池中放入一定数量的连接,当需要建立数据库连接时,只需从"缓冲池"中取出一个,使用完毕之后再放回去.我们可以通过设定连接池最大连接数来防止系统无尽的与数据库连接.更为重要的是我们可以通过连接池的管理机制监视数据库的连接数量、使用情况、为系统开发、测试及性能调整提供依据.     

The economics of climate change in agriculture

This paper presents a conceptual frameworkof the impact of climate change onagriculture. It assumes that climatechange will result in a fertilizationeffect and a shift of agro-ecologicalconditions away from the Equator towardsthe Poles. The agro-ecological shift islikely to reduce yield because of reducedacreage and the fertilization effect willincrease yield. The aggregate effectdepends on whichever of the two dominates. The overall effect of climate change may beless significant than its distributionaleffects and the results are consistentwith previous empirical studies. Theimpact of climate change depends on itspace. Faster changes in climate willresult in higher cost. The assessment ofthe cost has to consider that climatechange is a dynamic phenomenon that mayrequire continuous adjustment. Environmental regulation that emphasizesconservation may increase cost ofadjustment and environmental policiesshould emphasize adaptation andflexibility.     

某石化企业粉体料仓爆燃事故原因分析

本文以某企业HDPE料仓的一次爆燃事故为案例,通过分析事故的成因,提供了调查料仓事故的思路及整改方案的确定方法.     

Vegetation patterns and nature reserve construction in an extremely-arid desert in Anxi,NW China's Gansu Province

Anxi County is located in the northwestern part of the Hexi Corridor in gansu Province and has the sole national level nature reserve of extremely-arid desert in China.Phytosociological methods (Braun-Blanquet,1964) are used to classify plant community types in this area.Eleven are disting uished,including six of deserts,four of oases and one transitional type between deserts and oases.Direct gradient analysis (DCA) is employed to correlate the distribution of plant communities to physiogeographic conditions.This study makes clear that water is the most important ecological factor for the distribution of plant species and communities in this area.The effects of water have been demonstrated in different ways.A vegetation gradient from lower altitude to higher altitude in the southern part of the reserve is driven by a precipitation gradient.The effects of the depth of ground water table contribute to the differentiation of vegetation from desert to oasis in the flat area.In a finer scale,the washed gullies have obviously higher species richness and also higher vegetation cover than the surround gobi surfaces,possibly caused by the effects of floods.The vegetation patterns demonstrate that the area of Anxi County is a complete landscape unit.The range of the current nature reserve is not large enough for the purpose of conserving the unique biodiversity in this area.     

危险废物安全填埋场运行机制与收费标准

危险废物安全填埋场应探讨企业化经营模式。在单一处理模式、一体化经营模式和依托于大型企业模式中选择适宜的模式。填埋场建设资金筹集渠道中,由废物产生单位集资建设是可行办法。探讨了填埋场收费标准的计算方法,并给出计算公式。     

离子对烷基化法在2,4-D和2,4,5-T残留分析中的应用

有机阴离子可以和长碳链的季胺盐阳离子结合生成可溶于高介电常数有机溶剂的离子对.在此溶剂中,它可以和某些卤代烃发生复分解反应,生成季铵盐阳离子的卤化物及有机阴离子的相应烷基化物,故称离子对烷基化反应.此反应条件温和,转化率高,被广泛地应用于酸性及其它含活泼氢的有机化合物的烷基衍生物合成中.在这类有机物的分析中也得到应用.但尚未见应用于农药及其降解物残留分析中的报道. 2,4-D,2,4,5-T是典型的酸性有机农药,广泛用作农田除草剂.在二者的残留分析中,通常用CH_2N_2、BF_3CH_3OH、(CH_3)_2SO_4将它们烷基化,然后用气相色谱加以分析.近几年也有人用多卤素取代醇的BCl_3络合物或五氟苄基溴化物同Na_2CO_3作为