Measurements of surface contamination of spray equipment with pesticides after various methods of application

Abstract

A traditional method to determine operator dermal exposure is to quantify the amount of pesticide coming into contact with specific body regions and then to integrate the deposition density values with the total body surface. It is known that extremely high deposition values may occur in the hand region; however, the source of contamination is generally assumed to be direct splash or contact with the pesticide container. One of the parameters affecting operator/pilot exposure could be the transfer of pesticide residue, particularly in the case of pesticides with a longer half‐life, from contaminated surfaces of spray equipment by direct contact over extended periods. If the rate of skin absorption of pesticide is readily known, the expected values of daily dose for an operator or pilot may significantly rise due to the extended contact period. This study produced field data on the surface contamination of spray equipment used for ground and aerial applications. If field data on precise work practice (time‐motion) observations are incorporated, it may be possible to estimate the potential exposure of operator/pilot due to hand contact with contaminated surfaces.     

人口与消费对碳排放影响的分析模型与实证

从消费压力人口视角探讨碳排放问题,有利于正确判断和把握气候变化压力的人文因素,以及人口与消费可持续发展的动力学机制.本文通过对STIRPAT模型的扩展,应用岭回归方法计量分析人口、消费及技术因素对碳排放的影响.对我国1980至2007年碳排放情况的统计实证结果表明,扩展的STIRPAT模型对中国国情有较高的解释力.居民消费水平、人口城市化率、人口规模三个因素对我国碳排放总量的变化影响明显;现阶段我国居民消费水平与人口结构变化对碳排放的影响力已高于人口规模变化的影响力,居民消费水平与消费模式等人文因素的变化有可能成为我国碳排放的新的增长点;技术进步因素在此模型中对我国该阶段碳排放的解释力有限,表明我国未来通过技术进步减缓碳排放的潜力巨大.     

基于轮廓似然函数的PM_(10)极值浓度分析

以R软件为分析工具,选择GEV(generalized extreme value distribution)模型拟合四川省泸州市2003～2007年期间PM10每月最高日平均浓度数据,采用极大似然法估计模型的3个参数即位置参数、尺度参数、形状参数,利用所得的参数估计值计算得出某一标准值(如GB3095—1996)的重现期;进一步利用参数估计值计算轮廓似然函数,估计某一段固定时间间隔的PM10浓度的重现值以及其置信区间。结果表明,GEV模型能很好地拟合泸州市PM10数据,利用轮廓似然函数估计的不同时间间隔的重现值准确度高,统计结果可以为环境主管部门发布污染状况预警信息提供参考。     

厄尔尼诺事件对河南省降水的可能影响

本文采用小波变换方法分析了近50年来赤道东太平洋月海温距平序列和河南省月降水量距平序列的多层次时间尺度结构，对厄尔尼诺事件和河南降水的周期变化规律进行了对比分析，并讨论了厄尔尼诺对河南降水的可能影响。结果表明，厄尔尼诺事件对河南降水有一定程度的影响；表现为厄尔尼诺年大多对应河南雨涝年，而反厄尔诺年大多对应干旱年；NINO海区SST的冷暖结构和河南降水的旱涝变化之间具有较好的对应关系，而且两者都存在准2年和4－8年的周期变化。     

暴雨泥石流暴发的准周期性探讨

泥石流是山区的主要灾害类型，其发生条件和暴发规律尚在探索之中，泥石流过程本质上并不是纯随机事件，地形坡度，暴雨强度和风化岩土物质积累的组合决定了泥石流的规模，人们推测其暴发具有周期性，但并没有得到直接的证据。作者从山坡松散物质积累条件和泥石流暴发的概率分布出发，在考虑其发生规模的前提下，论证了泥石流暴发风险具有周期性，并且给出了其风险度及暴大风险重现期的估算公式，理论研究和调查结果表明，泥石流间隔期越长，其发长的规模将越大，这在制定山区防灾对策中应该特别注意。     

Influence of organic loading on an anaerobic sequencing biofilm batch reactor (ASBBR) as a function of cycle period and wastewater concentration

The effect of organic loading on the performance of a mechanically stirred anaerobic sequencing biofilm batch reactor (ASBBR) has been investigated, by varying influent concentration and cycle period. For microbial immobilization 1-cm polyurethane foam cubes were used. An agitation rate of 500 rpm and temperature of 30+/-2 degrees C were employed. Organic loading rates (OLR) of 1.5-6.0gCODl(-1)d(-1) were applied to the 6.3-l reactor treating 2.0 l synthetic wastewater in 8 and 12-h batches and at concentrations of 500-2000mgCODl(-1), making it possible to analyze the effect of these two operation variables for the same organic loading range. Microbial immobilization on inert support maintained approximately 60 gTVS in the reactor. Filtered sample organic COD removal efficiencies ranged from 73 to 88% for organic loading up to 5.4gCODl(-1)d(-1). For higher organic loading (influent concentration of 2000mgCODl(-1) and 8-h cycle) the system presented total volatile acids accumulation, which reduced organics removal efficiency down to 55%. In this way, ASBBR with immobilized biomass was shown to be efficient for organic removal at organic loading rates of up to 5.4gCODl(-1)d(-1) and to be more stable to organic loading variations for 12-h cycles. This reactor might be an alternative to intermittent systems as it possesses greater operational flexibility. It might also be an alternative to batch systems suspended with microorganisms since it eliminates both the uncertainties regarding granulation and the time necessary for biomass sedimentation, hence reducing the total cycle period.     

Critical considerations for future action during the second commitment period: A small islands' perspective

If the objective of the United Nations Framework Convention on Climate Change (UNFCCC) is to be achieved, Parties must commit themselves to meeting meaningful long‐term targets that, based on current knowledge, would minimize the possibility of irreversible climate change. Current indications are that a global mean temperature rise in excess of 2–3 °C would enhance the risk of destabilizing the climate system as we know it, and possibly lead to catastrophic change such as a shutdown of the deep ocean circulation, and the disintegration of the West Arctic Ice Sheet. Observations have shown that for many small island developing States (SIDS), life‐sustaining ecosystems such as coral reefs, already living near the limit of thermal tolerance, are highly climate‐sensitive, and can suffer severe damage from exposure to sea temperatures as low as 1 °C above the seasonal maximum. Other natural systems (e.g., mangroves) are similarly susceptible to relatively low temperature increases, coupled with small increments of sea level rise. Economic and social sectors, including agriculture and human health, face similar challenges from the likely impacts of projected climate change. In light of known thresholds, this paper presents the view that SIDS should seek support for a temperature cap not exceeding 1.5–2.0 °C above the pre‐industrial mean. It is argued that a less stringent post‐Kyoto target would frustrate achievement of the UNFCCC objective. The view is expressed that all countries which emit significant amounts of greenhouse gases should commit to binding reduction targets in the second commitment period, but that targets for developing countries should be less stringent than those agreed for developed countries. Such an arrangement would be faithful to the principles of equity and would ensure that the right of Parties to attain developed country status would not be abrogated.     

承德建龙3#高炉炉役后期安全生产特点

承德建龙3#高炉第1代炉役后期,炉身冷却壁大量损坏,炉缸部分冷却壁水温差超高,炉底、炉基温度达到安全警戒线,炉壳多处开裂变形,依靠外部打水维持生产的情况下,通过采取加强高炉操作,设备维护管理等技术措施,保证了高炉安全生产.     

城市电子废弃物资源化管理模式构想

通过对惠州市电子废弃物收集体系组成、去向以及电子废弃物处置方式的调查,分析惠州市电子废弃物收集和处置存在的一系列问题,结合实际提出了城市电子废弃物资源化管理模式的初步构想。     

清洁发展机制与中国碳排放交易市场的构建

清洁发展机制是《京都议定书》创设的实现全球碳减排目标的三大灵活机制之一,为我国的可持续发展作出了重大贡献,但其在我国运行中存在的问题也对我国参与国际碳市场和构建国内碳市场带来了风险与障碍.针对于此,本文对中国清洁发展机制项目的类型、数量、注册、签发等情况进行对比,发现我国虽然项目众多,但发展极不平衡.在此基础上,分析了中国清洁发展机制存在的主要问题,包括法律保障机制缺失,项目减排潜力发挥不充分,缺乏对转让技术的科学评估等.然后,通过介绍国际碳排放交易市场发展的不确定性和在2012年“后京都时期”的发展趋势,揭示了中国在这一过程中所承担的项目投资减少、成本增加等市场风险以及“碳泄漏”等环境风险.针对上述问题和风险,本文提出以现有清洁发展机制经验为基础构建中国国内碳排放交易市场的基本思路,即建立以排放交易法律体系为基础,以自愿碳交易市场构建为起点,以完善的监督管理体系为保障的中国碳排放交易机制.