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701.
为了解接种率及尿素添加量对农村生活垃圾厌氧发酵产甲烷的影响,选取3个水平的接种率(0.3、0.5、1.0)和3个水平的尿素添加量(1%、3%、5%)进行农村生活垃圾厌氧发酵实验。结果表明,在相同尿素添加量的条件下,接种率(0.3~1.0)越高越有利于甲烷产生,同时挥发性脂肪酸降解速率越快;而在相同接种率的条件下,随尿素添加量(1%~5%)的增加,甲烷产量呈先升高后降低的趋势。Gompertz动力学模型拟合结果表明,在接种率为1.0、尿素添加量为3%的条件下,厌氧发酵产甲烷延滞期较短(12 d),70 d累积甲烷产量最高(0.44 L·g-1 TS),发酵过程未发生酸化现象。  相似文献   
702.
三种人工湿地植物对城镇生活污水的处理   总被引:1,自引:0,他引:1  
谢云成 《湖北农业科学》2011,50(22):4586-4589
利用人工湿地处理技术探讨城镇生活污水治理与利用,研究菖蒲、美人蕉、麦冬3种植物在水力停留时间分别为1、3、5、7 d时对城镇生活污水的净化效果。结果表明,3种植物中美人蕉的处理效果最好,麦冬较差。在水力停留时间为7 d、密度为10株/m2时美人蕉对BOD5、CODcr、TP和TN的去除率分别为92.3%、88.2%、94.9%、94.6%。人工湿地生态系统适合以生活污水为主的城镇污水处理。  相似文献   
703.
Research on domestic violence has established a substantial association between intimate partner abuse and the abuse of children within the home. It is only recently however, that researchers have demonstrated the correlation between non-accidental injury in animals, and abuse of women by their intimate male partners. A growing body of evidence suggests that animal abuse can be an early indicator for other forms of violent behaviour. This research includes the responses of a sample of 23 women using refuge services in the Republic of Ireland. It investigates the connection between domestic violence and animal abuse, and ascertains if there is sufficient support service for animals and people relevant to domestic abuse. In the survey population, 57% of women reported witnessing one or more forms of abuse, or threats of abuse, of their pets. Five of which were reported to have resulted in the death of the pet. Eighty seven per cent of women felt a facility to accommodate pets would have made their decision to leave the family home easier. Four women disclosed that lack of such a service and concern for the welfare of their companion animals caused them to remain in their abusive relationships for longer than they felt appropriate. Nine families placed pets in the care of family or friends, one woman is unaware of the fate of her pet, while the pets of six families remained with the abusive male after his partner entered a refuge. The majority of women felt unable to talk to anyone about their fears for their pets' welfare. Many felt that there is no service which can provide temporary accommodation for womens' pets while they are in refuge. The results obtained support those found elsewhere in larger studies in the USA and UK, and demonstrate an association of animal abuse in households where there is reported domestic violence.  相似文献   
704.
Hepatitis E is a human disease mainly characterized by acute liver illness, which is caused by infection with the hepatitis E virus (HEV). Large hepatitis E outbreaks have been described in developing countries; however, the disease is also increasingly recognized in industrialized countries. Mortality rates up to 25% have been described for pregnant women during outbreaks in developing countries. In addition, chronic disease courses could be observed in immunocompromised transplant patients. Whereas the HEV genotypes 1 and 2 are mainly confined to humans, genotypes 3 and 4 are also found in animals and can be zoonotically transmitted to humans. Domestic pig and wild boar represent the most important reservoirs for these genotypes. A distinct subtype of genotype 3 has been repeatedly detected in rabbits and a few human patients. Recently, HEV genotype 7 has been identified in dromedary camels and in an immunocompromised transplant patient. The reservoir animals get infected with HEV without showing any clinical symptoms. Besides these well‐known animal reservoirs, HEV‐specific antibodies and/or the genome of HEV or HEV‐related viruses have also been detected in many other animal species, including primates, other mammals and birds. In particular, genotypes 3 and 4 infections are documented in many domestic, wildlife and zoo animal species. In most cases, the presence of HEV in these animals can be explained by spillover infections, but a risk of virus transmission through contact with humans cannot be excluded. This review gives a general overview on the transmission pathways of HEV to humans. It particularly focuses on reported serological and molecular evidence of infections in wild, domestic and zoo animals with HEV or HEV‐related viruses. The role of these animals for transmission of HEV to humans and other animals is discussed.  相似文献   
705.
EM对生活污水的有机物降解能力的研究   总被引:12,自引:1,他引:12  
研究了有效微生物群(EM)对生活污水中有物的去除效果,实验结果表明,(1)EM对有机污染物的去除应在好氧条件下进行,(2)当接种量在0.1/1000以下时,EM对有机物的去除有显著促进作用,去除率增幅达10%以上。  相似文献   
706.
In the summer of 2010 an epidemic of West Nile virus (WNV) occurred in Central Macedonia, Greece, with 197 human neuroinvasive disease (WNND) cases. In the following years the virus spread to new areas, with a total of 76 WNND cases in 2011, and 109 WNND cases in 2012 (14 and 12 WNND cases, respectively, in Central Macedonia). We established a surveillance system based on serological testing of domestic pigeons, using cELISA confirmed by serum neutralization test. In Central Macedonia, pigeon seroprevalence was 54% (95% CI: 49–59%) and 31% (95% CI: 24–37%) at the end of the 2010 and 2011 epidemic seasons, respectively. One serum was positive for neutralizing antibodies directed against Usutu virus. Pigeon WNV seroprevalence and incidence rates of human WNND after the 2010 epidemic were positively correlated (ρ = 0.94, at the regional unit level), while in 2011 the correlation (ρ = 0.56) was not statistically significant, possibly due to small number of human WNND cases recorded. To evaluate the efficacy of the system at alerting upon WNV enzootic circulation before the onset of human cases, we tested 270 pigeons in 2011 and 240 pigeons in 2012. In Central Macedonia, the first seroconversions in pigeons were recorded 44 and 47 days, respectively, before the first human WNND cases. Pigeon surveillance was used successfully for identification of areas with WNV enzootic transmission and for early warning. Timely diffusion of information to health authorities facilitated the implementation of preparedness plans to protect public health.  相似文献   
707.
从生态学的角度阐述了人工湿地系统中植物、根际微生物和基质在净化生活污水中的作用方式,探讨了湿地植物的关联性、根际微生物的互动性、基质的承载性及其相互关系和系统优化配置,展望了利用湿地植物、根际微生物和基质的特性进行优化配置,以提高湿地生活污水处理能力的可能性。  相似文献   
708.
尹海 《现代农业科技》2014,(10):227-228
在对国内先进的垃圾资源化利用技术进行调研基础上,根据盘锦市生活垃圾收运、处理实际情况,提出盘锦生活垃圾资源化利用对策,以为生活垃圾资源化利用提供参考。  相似文献   
709.
在对青岛市城阳区农村生活垃圾处理现状调查分析的基础上,提出了农村生活垃圾污染防治的对策及建议。主要包括:加强环保宣传教育,建立健全农村垃圾管理体系,推动垃圾分类,加强资源回收等。  相似文献   
710.
人工湿地处理生活污水的研究进展   总被引:11,自引:2,他引:9  
近年来,随着工业化城镇化的快速发展,大量生活污水未经处理即排放到自然水体中,导致我国地表水水质显著下降,富营养化现象严重,生活污水的处理日益受到广泛重视。人工湿地被证明是处理生活污水的一种经济有效手段,已成为生活污水处理的重要工艺之一。通过较为系统地综述表面流、水平潜流和垂直流3种流程人工湿地在处理生活污水时常用的植物种类、基质类型、水力负荷及净化效果,总结了目前人工湿地在生活污水处理中存在的一些问题,并展望了其未来发展方向。  相似文献   
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