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141.
炼焦过程排放挥发性有机物的排放特征和组成分布研究   总被引:1,自引:0,他引:1  
为控制炼焦排放以及为预防城市大气污染提供可靠的污染源数据支持,利用不锈钢采样罐和全自动预浓缩/GC/MS系统,研究了58-Ⅱ型和JN43-80型焦炉在装煤时刻和炼焦过程(包括装煤时刻)中挥发有机物(VOCs)的排放特征及其组成分布,分析了焦化行业排放VOCs的反应活性。研究发现,在装煤时刻和炼焦过程中,58-Ⅱ型焦炉产生的总挥发性有机物(TVOCs)浓度分别为7022μg/m~3和6266μg/m~3;JN43-80型焦炉产生的TVOCs浓度分别为4185μg/m~3和3298μg/m~3。装煤时刻产生的TVOCs浓度明显高于炼焦过程产生的。炼焦过程无组织排放的VOCs包含烯烃、烷烃、芳香烃、卤代烃以及少量的醛和酮,其中乙烯、乙烷、丙烯、苯、甲苯等为主要成分。这些产生的VOCs反应活性各不相同,活性最大的是烯烃类物质,其活性占TVOCs反应活性比重为(86.2±2.1)%;其次是芳香烃类物质,其活性比重为(9.2±3.1)%;反应活性最大的5个物种分别是丙烯、乙烯、1,3-丁二烯、1-丁烯以及苯乙烯。  相似文献   
142.
废水中氨氮的去除与利用   总被引:21,自引:0,他引:21  
化学沉淀剂可去除废水中的氨氮,并得到有用复合肥MgNH4PO4。探讨了诸反应对氨氮去除率的影响。  相似文献   
143.
借鉴环境风险源目标管理的理念,按照“分区、分类、分级”监测的原则,建立了化工园区地下水环境状况调查监测布点方法体系,并以某化工园区为示例展开应用研究。结果显示,该方法能对化工园区不同区域、不同类型、不同级别的地下水污染源构建差异化监测网络,解决化工园区地下水污染多元化监测布点问题,可为化工园区地下水环境状况调查监测布点方案的拟定或优化调整提供工作参考。  相似文献   
144.
The Horsfield’s bronze-cuckoo (Chalcites basalis) egg closely matches the appearance of its host fairy-wren (Malurus spp.) eggs. Mimicry of host eggs by cuckoos is usually attributed to coevolution between cuckoos and hosts, with host discrimination against odd-looking eggs selecting for ever better mimicry by cuckoos. However, this process cannot explain Horsfield’s bronze-cuckoo egg mimicry because fairy-wren hosts rarely reject odd-looking eggs from their nest. An alternative hypothesis is that cuckoos have evolved egg mimicry to disguise their eggs from other cuckoos. Female cuckoos remove one egg from the nest during parasitism and would potentially benefit by selectively removing any cuckoo egg that has already been laid in the nest because otherwise, their egg will be evicted by the first nestling cuckoo along with the host clutch. We used painted, non-mimetic eggs to test whether cuckoos selectively remove odd-looking eggs during parasitism. We found that they were no more likely to remove a non-mimetic egg from a superb fairy-wren Malurus cyaneus clutch than would be expected by chance. Thus, our study does not support the cuckoo egg replacement hypothesis to explain mimicry of host eggs by cuckoos.  相似文献   
145.
Numerous studies have focused on whether organisms can signal or perceive pheromones and use chemical signals in species and mate recognition. Recently, there have been an increasing number of studies investigating whether pheromones are used in mate choice. Yet, little attention has been paid in exploring the effects of pheromone-based mate choice on reproductive investment. We first tested this hypothesis by providing virgin Scytodes sp. females with a choice between two virgin males in the presence of chemical signals alone and found strong evidence of an odor-based mate preference. We then examined the consequences of the odor-based mate choice by allowing female Scytodes sp. that had previously made an odor-only mate choice to mate with preferred and non-preferred males, respectively. We measured the success of copulation, mortality of male, pre-oviposition interval, egg-sac weight, egg weight, fecundity, fertility, embryonic period, and size of offspring at hatching. Females that mated with the preferred males produced significantly heavier egg sacs that contained more and larger eggs with a greater fertility. Significantly more non-preferred males than preferred males were killed by spitting. However, pre-oviposition interval, embryonic period, and hatchling size were not affected by female mate choice. This study is the first to demonstrate that female spiders are able to regulate their highly valuable reproductive investment based solely on chemical signals.  相似文献   
146.
(Z)-Dodec-3-en-1-ol has been identified as the major component of the trail-following pheromone of nine species of Kalotermitidae belonging to six different genera, suggesting that this compound represents a common signal in this family of termites. The homogeneous nature of trail-following pheromones of Kalotermitidae well agrees with the monophyly of this family. It also supports the postulated position of this family as a sister group of the Rhinotermitidae and Termitidae, which also secrete C12-alcohols as trail-following pheromones. The significance of a trail pheromone in termites of the ‘one-piece’ life type, which spend their whole life within the same piece of wood, is discussed.  相似文献   
147.
Mixtures can be divided into simple (chemicals with comparable properties—health risk assessments on the chemicals) and complex, which can be further subdivided into defined (a reasonably distinct composition, created at a specific time and place despite dissimilar components—risk assessments on the common source) and coincidental (chemicals without similar properties or constant composition in time or space—risk assessments on the receptor). Interactions recognized are: independent action, dose addition (additivity), and potentiation (synergy and antagonism). Unpredicted outcomes need recognition. New approaches in higher education and multidisciplinary investigations are essential. The community of the Society for Environmental Geochemistry and Health should help clarify points such as when transformations in mixtures may become important enough to alter the classification and the risk assessment. The multidisciplinary community is also well placed to support the integration of nonchemical influences into mixture analysis and to contribute to the investigation of cumulative and multiple exposures.  相似文献   
148.
李政禹 《化工环保》2000,20(4):51-54
国际化学品安全卡(ICSC)是联合国国际化学品;安全规划处(IPCS)与欧洲聪明委员会合作编写的一套权威性化学品信息卡片。文中论述了推广使用ICSC的重要意义,介绍了安全卡的内容以及如何正确使用ICSC。  相似文献   
149.
涡喷消防车在化学事故中的抢险救援功能   总被引:5,自引:1,他引:4  
我国化学工业中的有毒气体的泄漏 ,化学品爆炸、失火等特种灾害的发生频度随化学工业的发展速度而同步增长。涡喷消防车是一种特大功率的气体、洗消剂、灭火剂的喷射平台 ,在化学事故的抢险救援中 ,对吹散、稀释、洗消事故现场的有毒气体 ,强制通风、驱散有毒烟雾和火场降温有独特功能 ,有利于赢得抢险救援的宝贵时间。在防毒抢险和消防救援中 ,在保护人民生命安全和消除毒害及爆炸事故方面有其重要作用。  相似文献   
150.
以美国《化学文摘》收录部分环境科学文献为例,对收录前后标题、文摘进行探析,论述科技论文文摘的特点及写作方法;指出英文摘要写作时,应注意文体的严谨、准确、翔实、明了和科学性等问题。  相似文献   
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