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121.
Regional Environmental Change - The adaptation of social-ecological systems such as managed forests depends largely on decisions taken by forest managers who must choose among a wide range of...  相似文献   
122.
人口与消费对碳排放影响的分析模型与实证   总被引:22,自引:2,他引:20  
从消费压力人口视角探讨碳排放问题,有利于正确判断和把握气候变化压力的人文因素,以及人口与消费可持续发展的动力学机制.本文通过对STIRPAT模型的扩展,应用岭回归方法计量分析人口、消费及技术因素对碳排放的影响.对我国1980至2007年碳排放情况的统计实证结果表明,扩展的STIRPAT模型对中国国情有较高的解释力.居民消费水平、人口城市化率、人口规模三个因素对我国碳排放总量的变化影响明显;现阶段我国居民消费水平与人口结构变化对碳排放的影响力已高于人口规模变化的影响力,居民消费水平与消费模式等人文因素的变化有可能成为我国碳排放的新的增长点;技术进步因素在此模型中对我国该阶段碳排放的解释力有限,表明我国未来通过技术进步减缓碳排放的潜力巨大.  相似文献   
123.
采用Zn-Se/不锈钢阴极的超声-电解法处理罗丹明B废水   总被引:1,自引:1,他引:0  
采用超声-电解法考察了Zn-Se/不锈钢阴极处理罗丹明B废水的效果及影响因素。正交实验优化结果表明:在电流密度为2.4A/dm2、废水初始pH为6、超声功率为160W、通气量为10L/h、m(Zn)∶m(Se)为1∶1.5的Zn-Se/不锈钢作阴极、Ti/TiO2和铁网为双阳极的条件下,超声-电解法处理罗丹明B废水120min,废水脱色率为98.97%,COD去除率为88.11%。  相似文献   
124.

Background, aim, and scope  

Pharmaceuticals are emerging pollutants widely used in everyday urban activities which can be detected in surface, ground, and drinking waters. Their presence is derived from consumption of medicines, disposal of expired medications, release of treated and untreated urban effluents, and from the pharmaceutical industry. Their growing use has become an alarming environmental problem which potentially will become dangerous in the future. However, there is still a lack of knowledge about long-term effects in non-target organisms as well as for human health. Toxicity testing has indicated a relatively low acute toxicity to fish species, but no information is available on possible sublethal effects. This study provides data on the physiological pathways involved in the exposure of Atlantic salmon as representative test species to three pharmaceutical compounds found in ground, surface, and drinking waters based on the evaluation of the xenobiotic-induced impairment resulting in the activation and silencing of specific genes.  相似文献   
125.

Background, aim, and scope  

Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves.  相似文献   
126.
采用浸渍法制备了CuO/BiVO4光催化剂,通过X射线衍射(XRD)、热重/差示扫描量热(TG/DSC)和傅立叶红外光谱(FTIR)对其进行了表征,并在可见光照射下考察了其光催化氧化亚甲基蓝(MB)的动力学特性。结果表明,Cu的掺杂并未改变BiVO4的晶型结构;Cu(NO3)2/BiVO4在热处理(30~300℃)过程中,NO3-已经完全分解,Cu最终以CuO的形式存在于CuO/BiVO4光催化剂体系中;掺杂不同量Cu的CuO/BiVO4中的Cu2+/Bi+(摩尔比)实测值与理论值相近,该系列光催化剂的合成过程具有较高的可信度;在可见光照射下,CuO/BiVO4光催化降解MB反应符合表观一级反应动力学特征;当Cu2+/Bi+为0.050时,反应动力学速率常数(k)达到最高值(0.4334h-1),此时的k比单体BiVO4作用下的提高了1.04倍;由于异质结的存在,CuO/BiVO4与单体BiVO4相比,电子和空穴的利用率大大增加,使得CuO/BiVO4的光催化活性较单体BiVO4有了大幅度提高。  相似文献   
127.
Five studies utilizing survey, experimental, and diary methods assessed the effects of being outdoors on subjective vitality. In Study 1, we used a vignette method to examine whether being outdoors was associated with vitality, above and beyond the influences of physical activity and social interactions. Study 2 explored the effects of being outdoors on vitality through an experimental design contrasting indoor and outdoor walks. In Study 3, participants were exposed to photographic scenes of either nature or buildings. Results showed that only the nature scenes enhanced subjective vitality. Studies 4 and 5 used a diary methodology to examine within-person variations in subjective energy as a function of being outdoors, again controlling for physical and social activity. Being outdoors was associated with greater vitality, a relation that was mediated by the presence of natural elements. Limitations of these studies are discussed, as well as their implications for research on energy and vitalization.  相似文献   
128.
臭氧氧化法深度处理纤维板生产废水的研究   总被引:1,自引:0,他引:1  
采用臭氧氧化法深度处理纤维板生产废水,探讨了臭氧投加量以及反应时间对COD和色度去除的影响,得到了最佳的工艺参数,并分析了这种处理方法的经济性。结果表明,当臭氧投加量为180mg/L、反应时间为30min时,纤维板生产废水的COD、色度去除率分别为58.3%、98.3%。采用臭氧氧化法深度处理纤维素废水的投资成本为600~700元/t,运行成本为0.8~1.2元/t,较Fenton氧化处理方法而言,在处理效率和经济成本上具有较大优势。  相似文献   
129.
CALPUFF is an atmospheric source-receptor model recommended by the U.S. Environmental Protection Agency for use on a case-by-case basis in complex terrain and wind conditions. The ability of the model to provide useful information for exposure assessments in areas with those topographical and meteorological conditions has received little attention. This is an important knowledge gap for use of CALPUFF outside of regulatory applications, such as exposure analyses conducted in support of risk assessments and health studies. We compared deposition of cadmium (Cd), lead (Pb), and zinc (Zn) calculated with CALPUFF as a result of emissions from a zinc smelter with corresponding concentrations of the metals measured in attic dust and soil samples obtained from the surrounding area. On a point-by-point analysis, predictions from CALPUFF explained 11% (lead) to 53% (zinc) of the variability in concentrations measured in attic dust. Levels of heavy metals in soil interpolated to 100 residential addresses from the distribution of concentrations measured in soil samples also agreed well with deposition predicted with CALPUFF: R2 of 0.46, 0.76, and 079 for Pb, Cd, and Zn, respectively. Community-average concentrations of Cd, Pb, and Zn measured in soil were significantly (p < 0.0001) and strongly correlated (R2 ranged from 0.77 to 0.98) with predicted deposition rates. These findings demonstrate that CALPUFF can provide reasonably accurate predictions of the patterns of long-term air pollutant deposition in the near-field associated with emissions from a discrete source in complex terrain. Because deposition estimates are calculated as a linear function of air concentrations, CALPUFF is expected to be reliable model for prediction of long-term average, near-field ambient air concentrations in complex terrain as well.  相似文献   
130.
煤粉炉掺烧干化污泥的污染物排放研究   总被引:2,自引:0,他引:2  
结合某电厂420 t/h四角煤粉炉掺烧污泥项目的实验室分析测试,了解煤粉掺烧不同含水率不同比例的干化污泥条件下烟气中污染物和灰渣中重金属的排放特性。结果表明,在实验研究配比和燃烧的条件下,大部分重金属元素Pb、Cu、Cr和Ni残留在灰渣中,Zn、Cd部分残留在灰渣中,As、Hg和Se等易挥发元素释放到烟气中,在灰渣中的含量很小。掺烧污泥后,灰渣中的重金属含量较单烧单煤都有了一定幅度的升高,Zn的含量是单煤的2倍,其余重金属是单煤的1.1~1.2倍。3种不同的掺混比例之间的污染气体排放浓度基本相似。烟气中主要污染物及重金属浓度可以满足现行国家标准。与单烧单煤相比,CO、HCl以及其他有机气体排放浓度基本相同;NH3的排放浓度较单煤有所升高;SO2、NOx和CO2排放浓度略有降低;飞灰浓度有所升高。烟气中的重金属,Hg含量升高了30%,Pb含量约为单煤的4.3~4.8倍。以上研究结果可为环保达标和飞灰利用提供基础数据。  相似文献   
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