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981.
982.
983.
Joanna P. Y. Chan Pei Rong Lau Ai Jie Tham Daiqin Li 《Behavioral ecology and sociobiology》2008,62(5):639-646
In experiments that comprised of three phases (fight, choice, and mating) under “seen” and “unseen” conditions, we examined
the effects of the outcomes of male–male contests and female eavesdropping on female mate choice and male mating success in
the fighting spider, Thiania bhamoensis (Salticidae). The results revealed female eavesdropping on agonistic interactions. Females that had watched an aggressive
interaction showed no distinctive preference for the winner over the loser, but they preferred the loser when they had not
observed a fight. Winners, however, achieved a greater mating success than did losers during the mating phase. Gaining access
to females was based on the insistence of the winners in courtship in terms of the number of quivers, rather than on the fighting
behavior of the males. Hence, the outcome of male–male contests may not be an important determinant of a male’s mating success
in T. bhamoensis. Instead, courtship display plays an important role in determining the success of male mating in this species. This study
also suggests that female mate preference may not be a good indicator of eventual female mate choice and male mating success.
Thus, a causal relationship between female mate preference and male mating success cannot be inferred.
Joanna P. Y. Chan, Pei Rong Lau, and Ai Jie Tham contributed equally. 相似文献
984.
为指导和支撑寒冷地区城镇污水厂升级改造,采用GPS-X软件的ASM1模型,构建了河北某污水处理厂CASS工艺提标改造模型,分别对污泥回流比(R_S)、反应区体积比(R_V)、充水比(λ)、运行周期(T)和不同水温的CASS运行方案等进行了数值模拟优化;同时,综合模拟结果,提出了升级改造技术方案,并予以实施。冬季运行结果表明,改造后的CASS工艺出水指标COD、氨氮和TN的浓度分别为(23.23±2.76)、(1.16±0.76)、(9.83±1.4) mg·L~(-1),能够稳定达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)一级A标准。 相似文献
985.
饮用水病原微生物污染是公共卫生面临的主要威胁之一,微生物监测在水质监测中的必要性日益受到人们的认可。在实际工作中,一般是通过检测指示微生物间接反映病原微生物的存在。通过调研国内外各组织、机构颁布的水质标准发现,近年来,我国环境质量标准和污染物排放标准中对于指示微生物的选择有从总大肠菌群向粪大肠菌群和大肠埃希氏菌(E.coli)转变的趋势,而美国环保署、欧盟、世界卫生组织、澳大利亚国家健康与医疗研究委员会等根据最新的流行病学证据,强调了大肠埃希氏菌(E.coli)、肠球菌(Enterococci)与粪便污染的相关性更强,可用于替代大肠菌群。建议我国在后续水质标准中对微生物指标进行增补修订时,参考国外经验,形成集成多种指示微生物与多种特定病原体的监测指标体系,以更好地保护环境功能和民众健康。 相似文献
986.
研究脱硫灰中杂质对石灰石脱硫活性的影响具有重要意义,采用烟气湿法脱硫用石灰石粉反应速率的测定方法,使用瑞士万通902智能电位滴定仪,分析了SiO2、Al2O3、Fe2O3、CaSO3与MgO等脱硫灰中5种杂质对石灰石脱硫活性的影响。结果表明,在实验浓度范围内,SiO2、Al2O3、CaSO3的加入在一定程度上促进了石灰石的溶解,而MgO、Fe2O3的加入在一定程度上抑制了石灰石的溶解。将脱硫灰与石灰石掺合作脱硫剂时,要综合考虑这5种杂质对石灰石溶出的影响,选择适宜的脱硫灰和石灰石掺合比。 相似文献
987.
Feifei Hao Weilin Guo Xin Lin Yanqiu Leng Anqi Wang Xinxin Yue Liangguo Yan 《Environmental science and pollution research international》2014,21(10):6723-6728
Increasing attention has been paid to pyrite due to its ability to generate hydroxyl radicals in air-saturated solutions. In this study, the mineral pyrite was studied as a catalyst to activate molecular oxygen to degrade Acid Orange 7 (AO7) in aqueous solution. A complete set of control experiments were conducted to optimize the reaction conditions, including the dosage of pyrite, the AO7 concentration, as well as the initial pH value. The role of reactive oxygen species (ROS) generated by pyrite in the process was elucidated by free radical quenching reactions. Furthermore, the concentrations of Fe(II) and total Fe formed were also measured. The mechanism for the production of ROS in the pyrite/H2O/O2 system was that H2O2 was formed by hydrogen ion and superoxide anion (O2 ·?) which was produced by the reaction of pyrite activating O2 and then reacted with Fe(II) dissolved from pyrite to produce ·OH through Fenton reaction. The findings suggest that pyrite/H2O/O2 system is potentially practical in pollution treatment. Moreover, the results provide a new insight into the understanding of the mechanism for degradation of organic pollutants by pyrite. 相似文献
988.
"一带一路"战略的目的在于促进亚洲、欧洲和非洲之间的往来联系,加强区域之间的经济合作与人文交流,从而达到各国共赢的可持续发展。"一带一路"战略目标是要建立一个政治互信、经济融合、文化包容的利益共同体、命运共同体和责任共同体。然而,由于东道国资源环境和生态环境等环境因素的不同以及限制性,在为企业带来一定的投资机遇的同时,使得企业在对外投资过程中面临的挑战日益增多。针对企业"走出去"时可能面临的环境风险,本研究建立了影响企业对外投资的环境影响因素指标体系,运用主成分分析法分析了中国企业在"一带一路"战略沿线国家的环境风险状况。根据研究分析,得出"一带一路"战略沿线国家环境风险指数,相关的资源限制和生态限制因素。最后,结合环境风险状况及以往的合作内容,总结了适宜沿线国家发展的投资类型,并提出相应的对策与建议。本研究通过对"一带一路"沿线国家环境风险评估,为我国在一带一路沿线国家规避环境和投资风险提供依据,推动绿色化"一带一路"建设,与沿线国家分享可持续发展成果。 相似文献
989.
Rong?YuanEmail author Tao?Zhao Jing?Xu 《Environment, Development and Sustainability》2017,19(6):2181-2198
The carbon emissions in service sectors have attracted increasing attention around the world. However, few studies have examined the driving forces for CO2 emissions from service sectors in developing countries. With the process of accelerating industrialization, China’s service sectors are facing growing pressure to pursue energy savings and emission reductions, especially in several developed regions. In this paper, in order to better understand how CO2 emissions in Beijing’s service sectors have evolved, we utilized a subsystem input–output decomposition analysis to study the pattern and driving factors of consumption-based emissions in Beijing’s service sectors. The results showed that the transportation sector and the Scientific Studies Technical Services sector caused the most CO2 emissions in Beijing’s service sectors. The emission intensity effect potentially reduced CO2 emissions by 10,833 Mt, primarily due to the decreased energy intensity of non-service sectors. Effects of demand and technology were mainly responsible for the increased CO2 emissions in Beijing’s service sectors. Such influence was mainly related to the external component of service sectors, indicating a strong pull effect exerted by service sectors on non-service sectors. Thus, decarbonizing the supply chain of service sectors and improving the energy intensity are necessary to alleviate CO2 emissions in Beijing. 相似文献
990.
响应面法优化聚磷硫酸铁的制备及其应用 总被引:2,自引:2,他引:0
采用单因素实验方法,针对制备聚磷硫酸铁(PPFS)的主要影响因素加以分析,包括酸度(nH2SO4/nFe2+、碱化度和nPO34-/nFe2+等。以生活污水中总磷(TP)的去除率为考察对象,采用Box-Behnken中心组合实验和响应面分析方法对主要影响因素加以优化,得到了二次响应曲面模型以及优化的水平值。结果表明,当把PPFS用于生活污水中TP的去除时,其最佳制备参数如下所列:酸度为0.1017,碱化度为12.21%,nPO34-/nFe2+为0.0560。通过回归分析,模型拟合性良好,在优化制备条件下得到的TP去除率预测值与实验值接近,误差为1.26%。 相似文献