敌敌畏,马拉硫磷在烟叶中残留量的测定

本文采用气相色谱法，用一根色谱柱，利用程序升温分析测定烟叶中敌敌畏，马拉硫磷农药残留量，该法的最低检出浓度敌敌畏为０．０２ｍｇ．ｋｇ＾－１，马拉硫磷为０．０１ｍｇ．ｋｇ＾－１，平均加标回收纺率为８７－１０２％，变异系数２．５７－４．６％。     

性能化防火设计中人员安全疏散的论证

性能化防火设计的根本出发点就是尽量减少火灾造成的人员伤亡和财产损失．它是一种系统的分析建筑物火灾安全问题的办法。性能化防火设计中人员能否安全疏散用可用疏散时间、所需疏散时间来判断。本文通过分析火灾时影响人员安全疏散的各主要因素．得出确定人员逃生时可用疏散时间的条件。同时分析了人员逃生时所需疏散时间的组成．讨论了预测人员疏散行动时间的简化计算方法。     

Aerosol optical properties derived from simultaneous sunphotometer and aureolemeter measurements in Lhasa

ＩｎｔｒｏｄｕｃｔｉｏｎＡｅｒｏｓｏｌｓｈａｖｅｔｈｅｐｏｔｅｎｔｉａｌｔｏｃｈａｎｇｅｔｈｅｇｌｏｂａｌｃｌｉｍａｔｅｂｅｃａｕｓｅｏｆｔｈｅｉｒｄｉｒｅｃｔｒａｄｉａｔｉｖｅｅｆｆｅｃｔｓａｎｄｔｈｅｉｒｉｎｄｉｒｅｃｔｅｆｆｅｃｔｓａｓｃｌｏｕｄｃｏｎｄｅｎｓａｔｉｏｎｎｕｃｌｅｉ.Ａｅｒｏｓｏｌｓａｒｅａｌｓｏｉｍｐｏｒｔａｎｔｃｏｍｐｏｎｅｎｔｓｉｎｂｉｏｇｅｏｃｈｅｍｉｃａｌｃｙｃｌｅｓａｎｄｉｎｈｅｔｅｒｏｇｅｎｅｏｕｓｃｈｅｍｉｓｔｒｙ ,ｗｈｉｃｈｃａｎａｆｆｅｃｔｔｒａｃｅ ｇａ…     

H型钢冷却过程的数值分析

此文根据非稳定热传导基本方程式积分得到离散化方程式,编写出计算程序.利用计算机求出H型钢内各点随时间变化的温度,绘出等温线,以研究H型钢理想的冷却方法.     

Ecotoxicological Characterisation and Classification of Existing Chemicals

GOAL, SCOPE AND BACKGROUND: In 1998, the International Council of Chemical Associations (ICCA) launched a global initiative to investigate more than 1,000 HPV chemicals (High Production Volume, > or = 1,000 t/a) within the refocused OECD HPV Chemicals Programme. Up to the OECD SIDS Initial Assessment Meeting in April 2004 (SIAM 18) 147 ICCA dossiers (ca. 230 CAS-No) have been assessed based on a harmonised data set. The environmental profile and an ecotoxicological characterisation of these chemicals are presented here. Data for acute aquatic toxicity were correlated among each other, as well as data for fish (LC50, LD50) and rodents (LD50). The data for acute aquatic toxicity are compared with other existing chemicals. METHODS: Data of the ICCA HPV chemicals from the OECD SIAM 11-18 are presented for: log Kow (as an indicator for bioaccumulation potential), biodegradation, acute aquatic toxicity and availability of long-term toxicity data. Correlation analysis was performed with log transformed data and a linear regression model was fitted to the data, if a significant correlation was found. Acute toxicity for fish and acute oral toxicity for rodents were correlated on a molar basis. Acute aquatic toxicity of the chemicals is compared with data from BUA reports 1-234 and a random EINECS sample (Knacker et al. 1995). RESULTS AND DISCUSSION: According to the dossier information, 71 of the 147 ICCA chemicals are not 'readily biodegradable', 21 have a log Kow > or = 3, and 44 are 'toxic' (LC/EC50 < or = 10 mg/L) or 'very toxic' (LC/EC50 < or = 1 mg/L) to aquatic organisms. For 77, only the base set (acute fish, Daphnia and algae) is available, for the rest at least one long-term test (fish or Daphnia) is available and three tests for a mere 14 others. Based on the data presented, the SIAM gives recommendations for Environment and Human Health. 22 chemicals have been identified as a 'candidate for further work' for Environment and 16 for Human Health. The highest correlation coefficient was obtained correlating fish and Daphnia (r2 = 0.79). LC50 (fish) is significantly correlated with LD50 (rodent), but data are widely scattered. The correlation is not improved after transforming LC50 (fish) to LD50 (fish), using BCF QSAR. Based on acute aquatic toxicity, 25.1% of the chemicals from the BUA reports 1-234 are classified as 'very toxic' (LC/EC50 < or = 1 mg/L). This proportion is 2.5-fold higher than the ICCA HPV chemicals and 1.4-fold higher than the random EINECS sample. CONCLUSIONS: Correlation coefficients for aquatic toxicity data are rather uniform (0.57-0.79) compared with literature data, but also the best correlation was observed between fish and Daphnia. Because the scatter around the regression lines is still considerable, simple predictions of ecotoxicity between species are not possible. Correlation of LC50 (fish) and LD50 (rodent) indicates that toxicity is different. Surprisingly, the correlation of fish and rodent toxicity is not improved by transforming LC50 values to internal LD50s. The selection of ICCA chemicals by market significance (production volume) leads to a classification of toxicity, which is more comparable to a random sample of EINECS chemicals than to German BUA chemicals. The latter were chosen for concern (for Environment or Human Health). RECOMMENDATIONS AND OUTLOOK: Of 147 dossiers assessed between SIAM 11-18, ca. 75% were sponsored by the three following countries: Germany (42), USA (37) and Japan (33). The current output is about 50 dossiers per year (70-100 CAS-No), but a trend for an increase of output is noticeable. Industry, national authorities, and OECD work on a further development to speed up the output. The number of chemicals with 'low priority for further work' and the work recommended for the 'candidates' (mainly exposure assessment) indicate that the data presented were adequate for an initial hazard assessment according to OECD requirements. From the ICCA HPV list (n = 880, state of 1999) 44% of the chemicals have data available to cover all SIDS endpoints for Environment and only 33% for Human Health (Allanou et al. 1999). This indicates the importance of the Initiative to provide information on existing chemicals. The authors agree with the expectation "...that the scientific information provided by this global initiative will be considered as an internationally accepted and harmonised basis for further steps of chemicals management." (ICCA 2002 b).     

BAT and BEP as instruments for reducing emissions of unintentionally produced POPs and development of guidelines under the stockholm convention

The 6th Intergovernmental Negotiating Committee (INC 6), under the Stockholm Convention on POPs, gave an expert group the mandate to develop guidelines for the application and implementation of best available techniques (BAT) and best environmental practices (BEP) for the prevention and reduction of unintentionally produced and emitted POPs, including polychlorinated dibenzodioxins/-furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB). Measures to reduce or eliminate the release of these POPs to the environment can be found in Article 5 of the Convention. BAT and BEP are already being applied as emission reduction instruments in a number of industrialised countries and are elements of other major international treaties, e.g. the UN ECE Protocol on POPs and the Marine Convention's OSPAR and HELCOM, and of the EU Directive for Integrated Pollution Prevention and Control (IPPC Directive). Existing concepts are presented and compared with the requirements of the Stockholm Convention. Consequences, perspectives and questions for the future intersessional work of the above-mentioned Expert Group are discussed.     

固体XM菌剂对生活垃圾减容和除臭的研究

在密闭的容器中考察不同条件下固体XM菌剂对生活垃圾的减容和除臭效果.结果表明,固体XM菌剂不但可防止新鲜生活垃圾变臭,而且对已产生的生活垃圾臭味具有明显的消除效果.固体XM菌剂可使新鲜的生活垃圾在降解过程中仅产生少量臭味,到15 d时基本消失并产生酯香气味,减容量可达46%.用质量分数为3%的固体XM菌剂处理已发臭的生活垃圾,15 d时氨气和硫化氢的释放量分别减少54.8%和49.0%.此外,保持较高的温度以及50%～60%的垃圾含水量,除臭效果最佳.从垃圾降解过程中渗滤液的产生量、澄清度、酸碱度和气味的变化分析得出,固体XM菌剂已成为垃圾发酵过程中的主导菌群,这可能是生活垃圾除臭的根本原因.     

广东省生态可持续发展定量研究:生态足迹时间维动态分析

生态足迹是一种定量测度生态可持续发展状态的指标和方法以支持可持续发展的决策。以广东省为案例，对广东1990年至2002年时间维的生态足迹及生态承载力进行计算和动态分析。结果表明，13年来，广东人均生态足迹和生态赤字不断增加，人均生态足迹从1990年的1．253hm^2增加至2002年的1．784hm^2，增加了42．38％；人均生态足迹赤字从0．817hm^2增加至2002年的1．393hm^2，但万元GDP生态足迹逐年下降。横向比较分析表明，广东2000年的人均生态足迹为1．636hm^2，低于全球平均水平(2．8hm^2)，同时也处于全球人均生态承载力(2．0hm^2)的范围，但超过中国人均生态承载力水平(O．681hm^2)；人均生态赤字(1．246hm^2)也高于世界平均水平(0．8hm^2)。因此，广东虽在全球尺度处于生态可持续发展状态，但生态系统的压力和强度甚高。     

二维定常泥流的数值模拟

本文以Ｎａｖｉｅｒ－Ｓｔａｋｅｓ方程为基本方程，将泥石流的一种特殊形式－泥流作为Ｂｉｎｇｈａｍ流体，用有限体积法对三种不同底部条件的泥流流场进行了数值模拟，给出了速率分布，并指出了泥流与清水流动的不同之处。     

温江县土壤中的硫

通过对温江县１２年水稻土种含硫量的测定表明，除两个土种外，１０个土种有效硫含量较低。对小麦、小稻和油菜茎杆及籽粒Ｎ／Ｓ测定，小麦、水稻缺硫。合理施用硫肥，增加土壤中的硫素营养，是当前农业环境中要注意的问题。