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991.
Guo Rong Liu Hong-Mei Sun Hong-Hao Wang Dong Yu Hao Do Rosario Alves Diana Yao Lu 《Journal of Material Cycles and Waste Management》2022,24(6):2314-2327
Journal of Material Cycles and Waste Management - The massive generation of municipal solid waste (MSW) has become an essential social problem that not only damages the ecological environment but... 相似文献
992.
利用生物完整性指数评价流域水生态状况,所得结果对水环境管理决策有重要指导意义。以2006年崇明东滩底栖动物监测数据为参照状态数据,利用长江口1991—2019年和杭州湾2004—2019年潮间带底栖动物监测数据构建底栖动物完整性指数(B-IBI),最终从56个候选指标中确定了6个核心指标:Marglef指数、软体动物相对多度、甲壳动物+多毛纲相对多度、ASPT、科级生物指数和捕食者相对多度。B-IBI评价结果显示:优秀等级样本有44个,良好等级72个,中等等级31个,较差等级7个,很差等级4个;杭州湾北岸水生态状况显著优于长江口南岸(P<0.05)。经验证,B-IBI与水质综合污染指数呈极显著相关(P<0.01),能够有效指示研究区域的水生态状况。 相似文献
993.
3-Hydroxy-2-butanone and the first encounter fight in the male lobster cockroach, Nauphoeta cinerea 总被引:4,自引:2,他引:2
Although agonistic behavior in the male lobster cockroach, Nauphoeta cinerea, has been known for more than 40 years, this is the first study to directly collect and quantify the emitted pheromones.
In the present study, emitted volatile pheromones were collected from each male pair for 60 min during the first encounter
fight and identified and quantified by gas chromatography–mass spectrometry. The major compound collected was 3-hydroxy-2-butanone
(3H-2B). The strength of the attack by the dominant male was classified into three categories from weakest (C) to strongest
(A). Of the 92 pairs, eight (8.7%) showed no agonistic interactions, and the amount of 3H-2B collected was 121.8±37.7 ng/male
pair. In the five pairs (5.4%) displaying attack strength C, the amount of 3H-2B collected was 689.6±273.7 ng/male pair, and
the attack duration was 9.6±2.4 min. In the 53 pairs (57.6%) showing attack strength B, the corresponding values were 5396.2±449.0 ng/male
pair and 22.7±1.6 min, while those for the 26 pairs (28.3%) showing attack strength A were 7910.4±1120.6 ng/male pair and
24.9±2.9 min. For both attack strengths A and B, a linear relationship was found between the amount of 3H-2B collected and
attack duration, suggesting that the longer the duration of the attack, the more 3H-2B was emitted. In addition, the rate
of 3H-2B emission for attack strength A was significantly higher than that for attack strength B. Using Vaseline-coating,
we demonstrated that, in the first encounter fight, the 3H-2B was emitted by the dominant male. 相似文献
994.
Preparation and application of efficient TiO2/ACFs photocatalyst 总被引:3,自引:0,他引:3
Activated carbon fibers (ACFs) supported titanium dioxide (TiO2) photocatalyst was developed by sol-gel method. The surface morphology and microstructure of the photocatalyst were characterized with scan electron microscope(SEM), X-ray diffraction patterns and specific surface area analysis. The prepared photocatalyst is specially helpful for the removal of low molecular weight organic pollutants in wastewater. Decomposition efficiency of methylene blue solution by TiO2/ACFs catalyst reached almost 100% under 60 min reaction, while the decomposition efficiency by pure TiO2 was only 25% under 3 h reaction. The mineralization of toluene aqueous solution was measured by total organic carbon instrument, and the evolution of intermediate species was detected by gas chromatograph instrument. The results indicated that the prepared photocatalyst not only enhanced the photoactivity of TiO2, but also suppressed the emergence of intermediate species, which may be more deleterious to human. The enhancement of photocatalysis was due to increased efficiency of adsorption and desorption, which were control steps in heterogeneous photocatalysis. 相似文献
995.
Industrial sustainability in China: practice and prospects for eco-industrial development 总被引:1,自引:0,他引:1
China is a large densely populated country undergoing rapid industrialization and is becoming one of the world's biggest consumers of natural resources. This circumstance provides a sharp contrast with other countries. As China is so significant in the global economy, studies of its eco-industrial development are very important. In this study we examined the state of eco-industrial development in China and have drawn conclusions from this analysis about some of the future prospects for sustainable development. In the analysis, we investigated the application of industrial ecology concepts by reference to several case studies. We have therefore described the current environmental situation in China, and have provided an overview of eco-industrial development and its implementation. Constraints to industrial sustainability in China have also been examined. We consider that eco-industrial development in China is in its infancy, and that closed loops involving chains and industrial symbiotic webs are the technological key and core of successful initiatives in the application of industrial ecology. In the case studies, we found that each system has different characteristics and management concerns. Our major conclusion is that even though China's Agenda 21 highlights the principles and sets the directions for eco-industrial development, these have not yet become essential ingredients in the country's industrial policy and practice for implementing Agenda 21. 相似文献
997.
河北省小城镇发展中的问题和对策 总被引:3,自引:0,他引:3
本文分析了河北省小城镇发展中存在的诸多制约因素 :阐述了城乡一体化 ,破除二元结构 ,构建有利于小城镇发展的社会环境的构想 ,并提出了关于改革城乡居民户籍管理制度、乡镇企业向镇区集中等一系列建议和措施 相似文献
998.
999.
利用载体经干燥后机械强度得到提高的特性,建立一种低胶体浓度固定化微生物制备技术:包埋剂为5.5%PVA、0.45%SA,固定液为饱和硼酸与0.6%硫酸铝的混合液,包菌量为0.4g/mL包埋剂。小球硬化24 h后洗净并放入30℃鼓风干燥箱干燥3.5 h后备用。制备出的固定化微生物氨氧化速率为24.3 mg/(L·h),相对活性为77.7%。 相似文献
1000.
以国际腐殖质协会(IHSS)推荐的胡敏酸提取方法为基础,以去有机质土壤中添加胡敏酸所配制的土壤为研究对象,引入超声作为胡敏酸提取的辅助条件,采用批次试验优化了土壤中胡敏酸的提取方法。结果表明,基于胡敏酸提取回收率和精密度,在室温下获得的优化提取方法为:液土比为8:1、提取次数为3次、Na OH溶液浓度为0.05 mol/L、超声功率为120 W、超声时间为30 min;在此优化条件下,胡敏酸的回收率为94.73%±1.50%,显著大于IHSS推荐方法的回收率64.76%±0.28%,变异系数CV为1.59%、小于10%。相对于IHSS提取法,此优化提取法具有胡敏酸提取回收率高、资源节约、胡敏酸变性小、提取时间短等优点。 相似文献