三峡库区端坊溪小流域防护林土壤改良效应研究

该文以土壤养分、容重、孔隙度、水分、下渗等指标为基础 ,采用时段对比法 ,全面分析了三峡库区端坊溪小流域防护林的土壤改良作用。结果表明 :随着林木的生长 ,防护林土壤改良作用明显 ;采用封山育林对改良防护林土壤结构效果显著。     

Studies on Barriers for Promotion of Clean Technology in SMEs of China

1 INTRODUCTIONAccording to the definition of SMEs in the TemporaryRegulation of Small and Medium Enterprise in China(2003): SMEs are those enterprises that have either less than2000 employees or 300 million RMB/year sales revenue, or400 million RMB fixed assets. SMEs generally account for99.88% of the total number of manufacturingestablishments in China in 2002, and they contributesignificantly to the social, economic and industrialdevelopment (Su, 2003).However, the majority of t…     

薄钢板焊缝手工超声波检测工艺

薄钢板焊缝（5～15mm）手工超声波捡测，越薄难度越大。但只要选用性能好的短前沿、较高频率、大K值的小晶片斜探头，以数字超声检测仪器组合调试好灵敏度，尽可能以直射波手动检测，应用工艺得当，就能取得较理想效果。手动检测是经济、快捷、实用的无损检测方法。     

存域网(SAN)在数字图书馆中信息安全的应用研究

数字图书馆是图书馆信息化建设的必然趋势 ,通过采用存域网 (SAN ,StorageAreaNetwork)技术 ,可以保证图书馆数据信息的可靠与安全 ,笔者分析了根据不同的需求 ,采用不同的SAN拓扑结构 ,为图书馆信息网络建设提供了多种可靠的解决方案     

Computer-aided classification of forest cover types from small scale aerial photography

The US National Park Service must map forest cover types over extensive areas in order to fulfill its goal of maintaining or reconstructing presettlement vegetation within national parks and monuments. Furthermore, such cover type maps must be updated on a regular basis to document vegetation changes. Computer-aided classification of small scale aerial photography is a promising technique for generating forest cover type maps efficiently and inexpensively. In this study, seven cover types were classified with an overall accuracy of 62 percent from a reproduction of a 1120,000 color infrared transparency of a conifer-hardwood forest. The results were encouraging, given the degraded quality of the photograph and the fact that features were not centered, as well as the lack of information on lens vignetting characteristics to make corrections. Suggestions are made for resolving these problems in future research and applications. In addition, it is hypothesized that the overall accuracy is artificially low because the computer-aided classification more accurately portrayed the intermixing of cover types than the hand-drawn maps to which it was compared.     

城郊型小城镇环境保护及生态建设初探--以扬州市邗江区甘泉镇为例

城郊型小城镇位于城乡结合部，由于受大城市的辐射，发展较快，做好城郊型小城镇的环境保护与生态建设具有重要的战略意义：本文以扬州市邗江区甘泉镇为例，探讨了城郊型小城镇环境保护及生态建设的思路。     

我国小城市固体废物区域管理系统中若干量化指标

简略介绍我国小城市的固体废物区域管理系统，指出在我国小城市固体废物实行区域管理的重要意义，系统论证了我国小城市固体废物区域管理中垃圾排放量，垃圾产生量的预测等若干重要量指标正确应用的意义与必要性。     

江浙沪地区小型燃烧温室气体减排研究

根据ＩＰＣＣＧｕｉｄｅｌｉｎｅｓ（１９９５）提供的方法，对１９９０年江浙沪地区小型燃烧中温空气体排放进行统计计算，２０００年的预测情况与９０年代的实际能源结构对比ＣＯ２减排的量为８４５．４万ｔ，减排了总量的１１％左右。     

分光光度法快速测定水中的COD

本实验改用小样本恒温箱加热,用分光光度法分析水中的 COD,与标准重铬酸钾法,库仑法比较,具有设备简单,操作方便、节省水、电,及同时分析批量样品等优点。     

我国小城镇水污染控制战略的思考

我国广大小城镇的水污染形势目前正处在加刷状态，而由于我国小城镇的具体国情，决定了小城镇的小污染不能采取与大中城市“同构”的控制措施，本文结合我国小城镇的具体特点，从战略角提出了以建设生态型小城镇为导向，以控制乡镇企业水污染为核心，以控制导流－生态工程为最终出路的小城镇水污染控制模式。