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1.
城市生活垃圾填埋场气体的产生、控制及利用综述   总被引:14,自引:0,他引:14  
对城市生活垃圾填埋场气体的产生、控制及利用进行了较为系统的综述分析,描述了填埋场气体的组成、性质及产生过程,分析了影响填埋场气体产生的因素,概括了填埋场气体控制手段和管理利用方式。  相似文献   

2.
油品在运输、装卸和储存等各环节都会产生静电。从分析油品在流动过程中静电产生的原理入手,分析了静电产生的原因,提出了具体的防静电措施。  相似文献   

3.
本文分析了棚户区改造过程中产生的环境污染问题,并就产生的原因及危害进行了分析,主要污染因子为建筑垃圾、扬尘、废弃塑料、油类、重金属、持久性有机物等.针对污染物产生的环境危害提出了防治对策.  相似文献   

4.
合成革的大量生产中产生经济效益,方便日常生活的同时,也给环境产生较大危害。尤其是在生产过程中所产生的有机废气,处理不当会对环境以及人体健康产生极大危害。因此,在日常生产过程中,要重视合成革有机废气治理。本文介绍了合成革有机废气产生、危害及主要治理方法基础上,重点论述了绿色理念下吸收法设计及应用。  相似文献   

5.
普查了锦州市古塔区"三废"产生和排放总体情况,分析了污染源及污染物产生和排放的特点,提出了相应的对策建议。  相似文献   

6.
堆肥过程中产生生物表面活性剂的细菌的筛选   总被引:5,自引:0,他引:5  
从不同温度的堆肥过程中 ( 45℃和 5 5℃ ) ,筛选了产生生物表面活性剂的菌种 ,对产生的生物表面活性剂进行了定性和定量的检验 .实验结果表明 ,Bacillussubtilis是堆肥过程中产生生物表面活性剂的主要菌种之一 ,并验证了其产生的生物表面活性剂为莎梵婷等脂肽类物质 .还对筛选出的优势菌种BacillussubtilisB产剂条件进行了优化 ,强化了它的产剂能力 ,结果表明碳源和氮源对产剂影响较大 ,而Fe2 浓度影响较小 .最后对筛选的菌种及其产生的生物表面活性剂在城市生活垃圾堆肥中的应用作了展望  相似文献   

7.
随着山区公路的快速建设,公路施工产生的环境问题也日益突出。结合山区公路的施工内容和施工过程,详细分析了山区公路施工过程中产生的环境问题及其影响,并就产生的环境问题探讨了山区公路施工期间的环境治理对策。  相似文献   

8.
对线性强化圆环横向压扁进行了研究,探讨了接触面内凹产生的机理,提出了内凹产生的判据。将理论结果与实验结果进行了比较。  相似文献   

9.
光照下铜离子对水中氢氧自由基生成量的影响   总被引:2,自引:0,他引:2  
研究了水溶液中铜离子与抗坏血酸、柠檬酸盐及藻等配合体系在高压汞灯光照下产生氢氧自由基的情况,其中铜与抗坏血酸系统反应最强,高压汞灯光照增强了铜与抗坏血酸反应产生氢氧自由基的过程,高压汞灯光照时所产生的自由基量为不光照时的6~7倍。同时铜(或抗坏血酸)单一的水溶液在光照条件下也能产生氢氧自由基。铜离子与柠檬酸钠溶液混合在光照下能产生氢氧自由基;铜离子与藻液混合能加倍藻液中氢氧自由基的产生。  相似文献   

10.
通过对金鸡岩洗选厂粉尘产生的原因进行了综合分析,找到了产生粉尘的主要原因,然后结合不同工艺环节点分别采用密封、喷水以及加装布袋式除尘器对粉尘进行了改造治理,尤其是对布袋式除尘器产生的二次扬尘通过修建吸尘池收到较好的效果。  相似文献   

11.
An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in Mt. Waliguan of remote continental area of China. High temporal resolved data were obtained using automated mercury analyzer RA-915 . Results showed that the overall hourly mean Hg0 concentrations in Mt. Waliguan were 1.7± 1.1 ng/m3 in summer and 0.6±0.08 ng/m3 in winter. The concentration in Yangtze Delta regional site was 5.4±4.1 ng/m3, which was much higher than those in Waliguan continental background area and also higher than that found in North America and Europe rural areas. In Beijing urban area the overall hourly mean Hg0 concentrations were 8.3±3.6 ng/m3 in winter, 6.5±5.2 ng/m3 in spring, 4.9±3.3 ng/m3 in summer, and 6.7±3.5 ng/m3 in autumn, respectively, and the concentration was 13.5±7.1 ng/m3 in Guangzhou site. The mean concentration reached the lowest value at 14:00 and the highest at 02:00 or 20:00 in all monitoring campaigns in Beijing and Guangzhou urban areas, which contrasted with the results measured in Yangtze Delta regional site and Mt. Waliguan. The features of concentration and diurnal variation of Hg0 in Beijing and Guangzhou implied the importance of local anthropogenic sources in contributing to the high Hg0 concentration in urban areas of China. Contrary seasonal variation patterns of Hg0 concentration were found between urban and remote sites. In Beijing the highest Hg0concentration was in winter and the lowest in summer, while in Mt. Waliguan the Hg0 concentration in summer was higher than that in winter. These indicated that different processes and factors controlled Hg0 concentration in urban, regional and remote areas.  相似文献   

12.
根据1979年5月,8月,11月胶州湾水域调查资料,并且与近几十年来的调查资料进行对比分析,探讨和研究胶州湾重金属Hg的平面分布、垂直分布、季节分布以及发展趋势.结果表明:胶州湾东北部海域春季污染较为严重,西南部的污染程度相对较轻;春季和夏季的表层含量大于底层含量,秋季时底层含量高于表层含量;而且春季Hg污染较为严重,秋季水质状况最好.从历史资料来看,1979年到1982年,Hg污染在加剧;1982年到1997年,从污染严重到缓和,在1997年就达到了一类水质的要求;1997年到1999年,水质更加清洁.  相似文献   

13.
刁江水体多相介质中As,Zn和Pb的空间和季   总被引:5,自引:0,他引:5  
调查了广西刁江河水中As,Zn和Pb的溶解态、悬浮颗粒态分布情况及季节变化,以及3种重金属在不同粒级沉积物中的分布情况. 结果表明:刁江流域河水与沉积物中3种重金属污染在流域尺度上的分布存在差异,沉积物污染更为严重. 与土壤污染一致,沉积物中3种重金属的污染范围扩散延伸到距离污染源近200 km的下游区域,其中车河矿区对As污染的贡献率明显高于大厂矿区,而对Pb污染的贡献率明显小于大厂矿区;不同重金属在水体中的赋存形态存在差异,河水中悬浮颗粒态Pb所占比例远高于As和Zn,这与3种重金属矿物的稳定性以及在不同粒级沉积物中的富集特征有关;河水中重金属的赋存形态存在季节差别,丰水期悬浮颗粒态重金属所占比例明显高于枯水期.   相似文献   

14.
Oxidative stress and DNA damages induced by cadmium accumulation   总被引:22,自引:0,他引:22  
Experimental evidence shows that cadmium (Cd) could induce oxidative stress and then causes DNA damage in animal cells, however, whether such effect exists in plants is still unclear. In the present study, Vicia faba plants was exposed to 5 and 10 mg/L Cd for 4 d to investigate the distribution of Cd in plant, the metal effects on the cell lipids, antioxidative enzymes and DNA damages in leaves. Cd induced an increase in Cd concentrations in plants. An enhanced level of lipid peroxidation in leaves and an enhanced concentration of H2O2 in root tissues suggested that Cd caused oxidative stress in Vicia faba. Compared with control, Cd-induced enhancement in superoxide dismutase activity was significant at 5 mg/L than at 10 mg/kg in leaves, by contrast, catalase and peroxidaseactivities were significantly suppressed by Cd addition. DNA damage was detected by neutral/neutral, alkaline/neutral and alkaline/alkaline Comet assay. Increased levels of DNA damages induced by Cd occurred with reference to oxidative stress in leaves, therefore, oxidative stress induced by Cd accumulation in plants contributed to DNA damages and was possibly an important mechanism of Cd-phytotoxicity in Vicia faba plants.  相似文献   

15.
The aerosol number concentration and size distribution were measured with the newly developed Wide-range Particle Spectrometer in summer and winter of 2006 at the urban site of Jinan City.Here reported the characteristics of fine particles of the different observation seasons.Relative high number concentrations for the particles in the diameter range of 10-500 nm were observed in both seasons.It was found that the dominant number distributed in particle diameter smaller than 100 nm and the percentage over the number concentration of all air particles is much higher than what has been measured in other urban sites over the world.The number mean diameter in summer was much smaller than in winter,strongly suggesting the different origin of ultrafine particles in different seasons.That is, particles in ultrafine mode mainly came from nucleation and new particle formation in summer while from traffic emission in winter. The diurnal variation also supported this point.Number concentration in the diameter range of 10-200 nm got their peak values at noontime,well correlated with the mixing ratio of SO_2 and the intensity of solar radiation in summer.While in winter,those in the same diameter range showed the main peaks during the traffic hours happened in the morning and evening.  相似文献   

16.
IntroductionAtrazine(2chloro4ethylamino6isopropylaminostriazine)isoneofthemostwidelyusedselectivepreandpostemergenceherbicidesforthecontrolofbroadleafandgrassyweeds.ThisherbicideisprimarilyusedincorncroppingsysteminNortheastandNorthofChina,andasoftentim…  相似文献   

17.
Massive amounts of pig manure are produced by intensive pig farm in China, and the composition of pig manure has changed much due to the use of feed additives. However, little is known about the exact Cu (copper) feed as additives or present as contaminants in pig feed and the residues in feces. One hundred and thirty-seven feeds and one hundred and forty-two fecal samples from 48 pig farms were collected in Beijing and Fuxin cities in 1999 and 2005, respectively. The concentrations of Cu were in the range of 6.86-395.19 mg/kg in the feed samples, and the mean values were in the order of weaner〉 grower-finisher〉 sow's feeds. The high concentrations over EU recommendations implied that excessive levels of Cu are fed on many pig farms in Beijing and Fuxin. Cu was also present in high concentrations in feces, and concentrations were highly variable. Cu concentrations in the feces from grower-finisher and weaner pigs were significantly greater than feces of sows. The super-intensive and small-scale farms had higher levels of Cu in feces than the middle farms. Cu concentrations in pig feces were approximately 5-times greater than in pig feeds. Feed management in grower-finisher pigs on super-intensive and small-scale pig farms is needed to reduce high Cu concentrations in feces and risks to soil contamination while feces are land-applied.  相似文献   

18.
The aim of this study was to characterize mercury (Hg) contamination in the coastal waters of the Southern Baltic Sea, and to investigate transformations of Hg in the initial links of the marine food chain. Concentrations of Hg in water, particulate matter, plankton and macrophytes at various stations in the coastal zone (a bay with restricted water exchange, near an industrial city, river mouths, and the open sea) were measured in 2006–2008. Hg concentrations observed in the Southern Baltic varied greatly, showing the highest average values in all environmental compartments near the river mouths. In shallow, sheltered parts of the gulf, where water exchange is restricted, Hg concentrations in the water and in macrophytes were elevated relative to those in the coastal zone of the deeper part of the bay and in the open Baltic. Distance to the river mouth, terrestrial runo , and quantity and quality of organic matter were more important than seasonal variations in controlling Hg and HgSPM concentrations in water samples. Mercury concentrations in the surface microlayer at the air/sea interface were over 10 times higher than those in the bulk surface water. Concentrations of Hg in macrophytes in the winter were significantly higher than those in the warm seasons (spring, summer, autumn). This was probably the combined e ect of higher availability of Hg in porewaters and leaf growth inhibition.  相似文献   

19.
青岛大气气溶胶水溶性无机离子的粒径分布特征   总被引:7,自引:0,他引:7       下载免费PDF全文
为了解大气颗粒物中水溶性离子的来源及环境效应,利用安德森采样器连续采集青岛近海2008年1~12月大气颗粒物分级样品,用离子色谱法分析其中主要的水溶性离子,并讨论其粒径分布特征.结果表明, NH4+、K+、Cl-、NO3-、PO43-、SO42-主要存在于粒径小于2.1μm的细粒子中,Na+、Mg2+、Ca2+、F-则主要存在于粒径大于2.1μm的粗粒子中.各离子的粒径分布存在明显的季节变化.NH4+、K+和SO42-四季均主要分布于细粒子中,而Mg2+和Ca2+则主要分布在粗粒子中,两者均在3.3~4.7μm出现峰值;Na+在春、夏、秋3个季节主要存在于粗粒子中,集中分布在3.3~7.0μm粒径范围内,而在冬季则集中分布于0.43~1.1μm且细粒子含量高于粗粒子;春季Cl-在粗粒子中分布较多,尤以2.1~3.3μm范围内的最为突出,而其他3个季节均是细粒子比例明显偏高;NO3-春、夏两季在粗、细粒子中的含量各占50%,秋、冬季节均为细粒子占多数;PO43-夏季只出现在0.65~1.1μm以及>11μm的粒径范围内,粗粒子占95%,其他3个季节则是细粒子含量较高;春季F-在3.3~4.7μm出现峰值,夏季各粒径均未检出,而秋、冬两季粗、细粒子各占50%.K+、NH4+、F-、Cl-、NO3-、SO42-和PO43-受供暖期燃煤取暖的影响较大.K+和NH4+在供暖期和非供暖期峰值均出现在0.43~0.65μm粒径范围;F-供暖期在0.43~0.65μm和3.3~4.7μm粒径段出现峰值;供暖期Cl-的峰值出现在0.43~0.65μm粒径段,而在非供暖期,则出现在2.1~3.3μm的粗粒径段;SO42-和NO3-在供暖期和非供暖期的峰值均出现在0.43~0.65μm和3.3~4.7μm粒径段;供暖期PO43-的最大峰值出现在0.43~0.65μm粒径段,而在非供暖期其最大峰值出现在3.3~4.7μm粒径段.  相似文献   

20.
主要调查研究环渤海湿地芦苇对TC、TN、TP的吸收通量。调查表明,2008年环渤海湿地的芦苇面积为20.08×104hm2。2009年,芦苇总生物量在7月、10月和11月的调查结果分别为267.2×104t、183.4×104t和138.0×104t。7月、10月和11月,芦苇对TC的吸收通量分别为115.58×104t、80.68×104t、64.23×104t;对TN的吸收通量分别为4.03×104t、1.45×104t、0.84×104t;对TP的吸收通量分别为0.37×104t、0.10×104t、0.031×104t。  相似文献   

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