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951.
Global climate change is one of the major environmental issues faced by humans.Existing evidence indicates that the anthropogenic push for a rise in the atmospheric concentration of greenhouse gases(GHGs)(particularly CO_2)has been a primary cause for global warming.Aside from economic and teclinological factors,demographic dynamics(including human consumption in a broad demographic sense)has been a major driver for CO_2 emissions.In this paper,we performed both nonlinear regression analysis(based on the STIRPAT model)and gray correlation degree analysis(based on gray system theory)on the impact of demographic dynamics on CO_2 emissions.Our results reveal that CO_2 emissions are positively correlated with population size and GDP per capita and negatively correlated with energy intensity.We also show that gray correlation degree with CO_2 emissions for five variables(i.e.,household consumption,urbanization rate,household size,population aging rate,population size)varies substantially:household consumptionurbanization ratehousehold sizepopulation aging ratepopulation size,with household consumption being the highest,and population size the lowest.To mitigate the impact of demographic dynamics on CO_2 emissions,it is of vital significance to nurture people's awareness of sustainable consumption and to adhere to current population control policies.  相似文献   
952.
Climate change is expected to be a major driving force of landscape in the coming decades.It will have a multitude of potential impacts that vary in intensity and effect according to region and sector.In the context of global warming,the climate of China has changed significantly in the recent 100 years.The reason for climate change in China is mainly due to irrational land use caused by human activities,which chiefly results in the rapid industrialization and urbanization process.Based on an assessment model,this research represents a picture of the impacts of climate change in six districts of Hangzhou region.The aim of this paper is to conclude,on the one hand,some of Hangzhou sensitivities in relation to the primary effects of climate change.On the other hand,a reflection is made on a methodology to formulate preconditions on a scientific basis for further research by design of integrated adaptation options for the future spatial developments in function to upgrade Hangzhou resilience in relation to climate change challenges.  相似文献   
953.
采用柠檬酸-硝酸盐燃烧法制备了光催化剂BiFeO3。采用SEM,XRD,FTIR等技术对光催化剂BiFeO3进行表征。表征结果显示,光催化剂BiFeO3晶相纯、粒径小、比表面积大,存在Fe#x02014;O的弯曲振动和伸缩振动。实验结果表明:通过鼓气及加入H2O2可有效提高BiFeO3对甲基紫可见光催化降解的效率;在300mL质量分数为1.5#x000d7;10-5的甲基紫溶液中加入0.9g光催化剂BiFeO3和0.1mL质量分数为30%的H2O2溶液,当反应时间为240min时,甲基紫去除率可达99%。  相似文献   
954.
采用Fenton试剂氧化法处理分散橙、分散紫和分散蓝3种染料结晶废母液。研究了H2O2加入量、n(H2O2)#x02236;n(Fe2+)和废母液pH对COD去除率或TOC去除率的影响。对TOC去除反应分段进行了动力学方程拟合,并探讨了反应机理。实验得到的分散橙、分散紫和分散蓝的废母液处理工艺条件:H2O2加入量分别为264.4,352.9,441.2mmol/L;n(H2O2)#x02236;n(Fe2+)分别为20,10,20;废母液pH=3。3种废母液在0~20min和20~120min两个阶段的反应与二级动力学拟合方程的相关性最好。3种废母液经Fenton试剂氧化处理后,部分有机物降解为小分子有机酸,部分有机物完全矿化。  相似文献   
955.
In Taiwan, typhoons usually result in a large amount of waste that needs to be removed in a short time from July to October. This study reviewed the relevant regulations on the clean-up of typhoon waste, including emergency response regulations, organizations and information systems; and we also discuss different typhoon waste clean-up and disposal methods. The results indicate that the parameters other than the maximum wind speed, such as the maximum accumulated rainfall, flooded area, waste output, sludge output, disinfected area and government dispatched attendance reached statistical significance (p < 0.05). Waste, tree branches and bird carcasses were primarily incinerated, while silt and building materials were buried, and pig and cattle carcasses were placed in a landfill with the tertiary treatment of wastewater. This study also reports on the relevant regulations for prevention of epidemics among personnel working in disaster areas. The results can provide important references for the disposal of typhoon waste in developing countries. As Asian countries have similar life styles and are often attacked by typhoons, the results of this study provide Asian countries with the operating experience of Taiwan in emergency treatment of solid waste resulting from typhoons as a reference for them to plan response systems and operation.  相似文献   
956.
Antibiotics are widely used in daily life but their abuse has posed a potential threat to human health. To evaluate the toxicity of chloramphenicol (CAP) at the protein level, the interaction between CAP and human serum albumin (HSA) was investigated by fluorescence, Ultraviolet–visible (UV–Vis) absorption, Fourier transform infrared (FT-IR) spectroscopy and molecular docking methods. Fluorescence data revealed that the fluorescence quenching of HSA by CAP was the result of the formation of CAP–HSA complex, and the binding constant was determined to be 3.196?×?104 L mol?1 at 310 K. The thermodynamic determination indicated that the interaction was driven by enthalpy change and entropy change together, where the multiple hydrogen bonds (CAP and the residues Arg 222 and His 242 of HSA) and van der Waals forces were the dominant binding force. The site marker competition revealed that CAP bound into sub-domain IIA of HSA. The binding of CAP induced the drastic reduction in α-helix conformation and the significant enhancement in β-sheet conformation of HSA. Molecular docking study further confirmed the binding mode obtained by experimental study. This work provides a new quantitative evaluation method for antibiotics to cause the protein damage.  相似文献   
957.
从高硫污染的活性污泥中富集培养,分离纯化得到一株可以降解噻吩的菌株s_4,并对该菌株的形态特征进行观察。应用Design—Expert8.0.5b软件进行响应面优化实验,研究了反应时间、噻吩浓度、微生物浓度3个因素的组合对菌株s_4脱硫效果的影响,并拟合得到多元二次回归方程,得出最佳实验条件。拟合结果表明,当反应时间27.46h,噻吩浓度为1.04%,微生物浓度4.04%时,预测噻吩降解率为14.8%,通过验证得最佳条件下的降解率为14.3%,与预测值相符。  相似文献   
958.
通过静态动力学和热力学吸附实验,研究了温度、共存离子以及溶质的初始浓度对As(V)在金红石TiO2颗粒表面吸附的影响,探讨了As(V)在金红石TiO2颗粒表面吸附特性及机理。结果表明,在As(V)初始浓度为10mg/L,pH为7的条件下,25℃时的吸附量0.41mg/g高于30℃时的吸附量0.31mg/g,As(V)在金红石TiO,上的吸附为放热过程。CaCl2和MgCl2的添加对As(V)在金红石TiO2表面吸附起到明显的促进作用。T=25℃,Ca2+或Mg2+浓度为10mmol/L时,As(V)吸附量分别为0.64和0.56mg/g,Ca2+比Mg2+对As(V)吸附促进作用强。As(V)在金红石TiO2的吸附等温线符合Frendlich方程,Lagergren二级动力学方程能较好地描述As(V)在金红石TiO2颗粒表面吸附的动力学过程。  相似文献   
959.
西安是空气污染监控和防治有代表性的西部大型城市。研究了西安市及周边地区上空气溶胶光学厚度与PM10浓度的关系模型。利用2011—2012年MODIS卫星气溶胶光学厚度(AOD)遥感产品,通过数据匹配,利用地面气象观测站点的能见度数据和相对湿度数据对AOD产品进行垂直标高订正和湿度订正,2项订正显著提高了AOD和地面PM10浓度的相关性,相关系数从0.36提高到0.65,按季节分类统计和订正春至冬四季的相关系数分别为0.57、0.71、0.62和0.87,夏季和冬季的订正更为有效,可用性更高,这可能由于受到不同季节气溶胶来源和特征的影响。为研究中国西部大型城市,特别是西安市空气环境监测和区域联防联控提供了一种有效方法。  相似文献   
960.
This study aims to develop an inexact two-stage optimization model to gather manure distributed over the southwest Taiwan and convert it into bioenergy. In the method, local optimization of each hauling zone is performed first using a gray mixed-integer programming model. Then, the hauling zones are prioritized by its performance on four gray scenarios. Although the biogas yield and the manure generation rate are ambiguous, one can easily evaluate his opportunity and risk by gray interval, which is a group of values within the lower and upper bounds. The analyses reveal that the biogas yield dominates the profit in this project, and it leads to the failure of the project when the biogas yield is below the level of 0.2 m3 kg?1. With the goal of reducing 45% of methane emissions from pig farms, seven hauling zones are required to be developed. The farmers living in these zones from the project get carbon credits ranging from 478 to 3269 ton CO2eq per year, and the investors own the carbon credits in the range of 3264–11820 ton CO2eq per year. Through the carbon trading, both the investors and pig farmers are able to make profits by trading their carbon credits.
Implications:Biogas recovered from hoggery can be used as a bioenergy source and mitigate the atmospheric greenhouse effect and global warming. This research develops an inexact two-stage optimization model to evaluate the potential of gathering manure for biogas and converting it into bioenergy. The analyses reveal that the biogas yield dominates the profit in this project, and it leads to the failure of the project when the biogas yield is below the level of 0.2 m3 kg?1. This study has provided a useful reference for the management of biogas production and carbon trading from hoggery for bioenergy.  相似文献   
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