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941.
Summary. We investigated the hypothesis that aggregation signals produced by male webbing clothes moths (WCM), Tineola bisselliella (Hum.) (Lepidoptera: Tineidae), and close-range male attractant signals produced by females have a pheromonal basis, at least
in part. Gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometric analyses of bioactive methanolic
extracts of male WCM disclosed three candidate pheromone components: hexadecanoic acid methyl ester (16:Ester), (Z)-9-hexadecenoic acid methyl ester (Z9—16:Ester), and octadecanoic acid methyl ester (18:Ester). In bioassay experiments in a large Plexiglas™ arena, a blend of
synthetic 16:Ester plus Z9—16:Ester was attractive to male and virgin (but not mated) female WCM; the 18:Ester was inactive.
GC-EAD analyses of pheromone gland extracts from female WCM revealed (E,Z)-2,13-octadecadienal (E2Z13—18:Ald) and (E,Z)-2,13-octadecadienol (E2Z13—18:OH) as candidate sex pheromone components. In arena bioassay experiments, 1—5 female equivalents of synthetic E2Z13—18:Ald (0.2 ng) and E2Z13—18:OH (0.1 ng) were more attractive to male WCM than were two virgin female WCM. We anticipate that the combination of
aggregation and sex pheromones, male-produced sonic aggregation signals, and habitat-derived semiochemicals will be highly
effective in attracting male and female WCM to commercial traps.
Received 12 January 2001; accepted 8 June 2001. 相似文献
942.
Fairness is a relative concept with multiple, subjective and competing notions of what it is, how to achieve it, and for which beneficiaries. Fairtrade International's collaborative efforts to develop a standard to certify Fairtrade Carbon Credits (FCCs) brought together multiple stakeholders in a deliberative context. This paper uses Q methodology to empirically assess the notions of fairness this wider consultation group held. Three distinct ‘factors’ (or perspectives) are identified, and discussed in relation to a multi-dimensional framework for exploring fairness. The first factor prioritises development delivered through organisations, participation in decision-making and use of minimum prices to adjust trade imbalances. The second factor conceptualises a non-exclusive approach maximising generation and sales of FCCs, involving a commodity chain where everyone performs their optimum function with financial transparency and information-sharing to facilitate negotiations. The third factor involves minimising intervention, allowing carbon commodity chains and project set-ups to function efficiently, and make their own adjustments to enhance benefits access and quality received by beneficiaries. The three factors reflect debates within carbon and fair trade spheres about who should be playing which roles, who should be accessing which benefits, and how people should be supported to interact on an uneven playing field. Communicating findings to standards organisations enables a more open and inclusive policy process. Our research provides a critical reflection on these plural notions of fairness, identifying areas of (dis)agreement within the FCC dialogue, and provides a wider, yet manageable, set of inputs for supporting the FCC process during its inception and subsequent implementation. Clearer definitions of “fairness” are also useful for standards organisations in reviewing ex post whether “fairness” goals have been met. 相似文献
943.
944.
采用泄漏检测与维修( LDAR)技术进行了全面检测和统计分析,分析泄漏的原因并通过维修减少泄漏。结果表明:芳烃抽提装置容易泄漏的元件主要为连接件和阀门,主要分布在泵区;SV≥5000μmol/mol的泄漏密封点占总密封点数的0.57%,对总泄漏量的贡献达到了82%,是造成泄漏排放的主要部分。设备管阀件泄漏造成的加工损失率为0.0009%,泄漏点停工维修修复率为83%,停工维修后整体泄漏率为0.03%;VOCs减排率为71%。 相似文献
945.
The purpose of this paper is to systematically analyse a typical planning process in the offshore industry from the perspective of causes of major accidents, with the ultimate aim of identifying factors that affect the risk for major accidents occurring. We first study and describe a typical planning process for offshore oil and gas operations in Norway. Then we analyse a number of theories of major accidents, to see how the different theories and their explanations of causes and contributing factors can be of relevance for future plans and planning processes. Finally, we review accident investigations to search for evidence of how weaknesses in planning processes can contribute to major accidents through the above identified factors. Also, we try to identify any additional factors that have not been recognised through the theoretical review. This provides empirical support for the theoretical basis. Thirteen factors which directly or indirectly can influence the planning process causing a major accident potential are identified. These are exemplified through a review of investigation reports. The paper suggests that planning process should focus more on increasing quality in the plans at an early phase, with examples from incidents, and illustrate the relation between planning quality and potential for major accidents. 相似文献
946.
947.
本文通过对国内外近几年有关电解铝含氟化氢工业尾气净化处理大量的参考文献的分析研究及国内外电解铝生产企业在尾气治理方面的技术应用和尾气净化装置运行状况的调研,结合自己的专业特长和工程经验,建立一套有关电解铝含氟化氢尾气在处理、净化氟化氢方面的技术方案,设计制作一套湿法氟化氢吸收中试装置,从工艺方案优化设计、安全运行、设备设计及选材、自动控制、建立相关的副产物检测方法和后续产物的综合利用等方面进行了研究和探讨。 相似文献
948.
为解决干冰膨胀烟丝生产线冷端液体工艺泵因机械密封长期超压和气缚现象造成损坏发生CO2泄漏而导致紧急停机抢修的问题,对干冰膨胀线冷端工艺罐系统进行了优化改进。在工艺泵吸口前管路引一根气相平衡管至工艺罐顶部,当泵吸口前管路有CO2液体时,输送管路内气化的CO2气体通过气相平衡管线释放回工艺罐内,不会进入工艺泵体内。应用结果表明,工艺泵内的憋压和气缚现象消失了,机械密封受到保护。改造前机械密封平均一个季度更换一次,改造后机械密封使用5年未损毁,达到保护干冰膨胀线冷端工艺泵机械密封的目的。 相似文献
949.
950.
本文探索了微波作为辅助手段处理高炉煤气洗涤水过程中,微波辐射功率、微波辐射时间、聚合氯化铝(PAC)加入量、磷酸加入量对高炉煤气洗涤废水处理效果的影响。结果表明,微波和PAC混凝联用处理高炉煤气洗涤废水具有作用时间短、聚沉能力强等特点,可以有效去除废水中悬浮物,降低硬度及浊度。 相似文献