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1.
Fu Li Chen Yi Yang Xinyi Yang Zuyao Liu Sha Pei Lei Feng Baixiang Cao Ganxiang Liu Xin Lin Hualiang Li Xing Ye Yufeng Zhang Bo Sun Jiufeng Xu Xiaojun Liu Tao Ma Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air... 相似文献
2.
When accounting the CO2 emissions responsibility of the electricity sector at the provincial level in China,it is of great significance to consider the scope of both producers’ and the consumers’ responsibility,since this will promote fairness in defining emission responsibility and enhance cooperation in emission reduction among provinces.This paper proposes a new method for calculating carbon emissions from the power sector at the provincial level based on the shared responsibility principle and taking into account interregional power exchange.This method can not only be used to account the emission responsibility shared by both the electricity production side and the consumption side,but it is also applicable for calculating the corresponding emission responsibility undertaken by those provinces with net electricity outflow and inflow.This method has been used to account for the carbon emissions responsibilities of the power sector at the provincial level in China since 2011.The empirical results indicate that compared with the production-based accounting method,the carbon emissions of major power-generation provinces in China calculated by the shared responsibility accounting method are reduced by at least 10%,but those of other power-consumption provinces are increased by 20% or more.Secondly,based on the principle of shared responsibility accounting,Inner Mongolia has the highest carbon emissions from the power sector while Hainan has the lowest.Thirdly,four provinces,including Inner Mongolia,Shanxi,Hubei and Anhui,have the highest carbon emissions from net electricity outflow- 14 million t in 2011,accounting for 74.42% of total carbon emissions from net electricity outflow in China.Six provinces,including Hebei,Beijing,Guangdong,Liaoning,Shandong,and Jiangsu,have the highest carbon emissions from net electricity inflow- 11 million t in 2011,accounting for 71.44% of total carbon emissions from net electricity inflow in China.Lastly,this paper has estimated the emission factors of electricity consumption at the provincial level,which can avoid repeated calculations when accounting the emission responsibility of power consumption terminals(e.g.construction,automobile manufacturing and other industries).In addition,these emission factors can also be used to account the emission responsibilities of provincial power grids. 相似文献
3.
畜禽粪便中大量有机污染物污染着人们赖以生存的土壤和水体,粪尿分解产生的大量有害气体污染了大气。本文结合日照市畜牧业生产的实际,对日照市畜牧业生产对环境的污染现状进行了分析,找出了日照市畜牧业生产对环境污染产生的主要原因和存在问题,提出畜牧业生产对环境污染的防治对策。 相似文献
4.
通过田间定位试验,研究了石灰(L)、钙镁磷肥(G)、泥炭(P)、猪粪(M)、石灰 泥炭(L P)、石灰 猪粪(L M)、钙镁磷肥 泥炭(G P)、钙镁磷肥 猪粪(G M)等改良材料对新罗区特钢厂附近的重金属污染田的长期改良效应.结果表明:大部分处理可提高土壤的pH值、有机质含量,降低了土壤的有效锌含量,石灰 泥炭、钙镁磷肥 泥炭的改良效果要优于单施有机、中性化改良剂和其它处理,和对照相比,有效锌含量和糙米锌含量最高分别降低了59.2%、36.2%. 相似文献
5.
Xiang Laisheng Guo Yajun Li Zhanfang . School of Management Northeastern University Shenyang Liaoning China . Development Research Center of Liaoning People’s Government Shenyang Liaoning China 《中国人口.资源与环境(英文版)》2007,5(2):49-52
In the high technology industry, small and medium sized technology enterprises (SMSTEs) play a pivotal role in advancing the whole industry. To achieve sustainable development, they need to extend their scope of business activities beyond a national view and exploit international market actively to meet international competitions that increase quickly in the form of allocating resources within the scope of the world. However, the SMSTEs are also facing risks associated with themselves during the process of exploiting international market owing to their own restrictions, so what they should do is to consider risk evaluations in exploiting the international market. 相似文献
6.
生态足迹影响因子的定量分析 总被引:2,自引:0,他引:2
蒋莉 《长江流域资源与环境》2005,14(2):238-243
人口的膨胀和人类工业化进程的加剧,使得人类向自然界获取越来越多的资源,同时向环境源源不断的输入废弃物,已经严重超过了自然生态系统的供给能力和环境容量,生态环境日益恶化,水土流失、草场退化、植被消亡、生物多样性锐减、全球变暖等情况已经严重到难以遏制的地步,危及到人类自身的生存。在和平与发展成为世界两大主题的今天,人们越来越关注可持续发展的问题。在现有资料的基础上,利用主成分分析方法,定量地讨论了中国各省(区市)1999年生态足迹大小与其影响因子间的关系。结果表明,生态足迹的大小是各省(区市)的大中型企业个数、全社会固定生产投资等众多因子共同作用的结果,其中总人口和GDP是生态足迹大小的主要影响因子,其因子载荷量分别达到了0.940和0.913。值得一提的是非农业人口与生态足迹的相关系数超过了农业人口,这说明由于消费模式和生活水平等的差异,非农业人口对生态足迹的影响大于农业人口对生态足迹的影响。在此基础上建立了生态足迹影响因子的多元线性回归模型,以期为生态足迹在进行区域可持续发展评价的方法上提供新的思路。 相似文献
7.
不同轮作模式下作物根际土壤养分及真菌群落组成特征 总被引:10,自引:8,他引:2
为研究宁夏中部干旱带不同轮作模式下土壤养分及真菌群落组成的特征,以谷子轮作大豆(MRG)、轮作籽粒苋(MRA)、轮作藜麦(MRQ)及谷子连作(CK)为对象,测定了土壤养分含量,并利用Illumina MiSeq高通量测序平台测定了土壤真菌的ITS变异区序列.结果表明,不同轮作模式对土壤养分的影响存在差异.3种轮作模式下土壤pH和电导率均有所下降,土壤全氮、全钾、全磷和有机质含量均上升,OTUs数和α多样性指数均高于连作.真菌群落组成研究结果显示,子囊菌门(Ascomycota)为4种模式下的优势菌群.聚类分析显示MRA和MRG的真菌属组成最为相似,其次是MRQ,CK与3种轮作模式相差较大.相关性分析显示,土壤养分与几种优势真菌属呈显著相关性(P<0.05或P<0.01),土壤全氮、全钾、硝态氮和有机质含量是影响土壤真菌群落最主要的因子.主成分分析(PCA)表明,MRG轮作模式优于MRA和MRQ模式.综上所述,轮作提高了真菌群落多样性指数,改变了土壤真菌群落结构,改善了土壤肥力状况,其中以谷子与大豆轮作效果最佳,建议将谷豆轮作作为中部干旱带杂粮产业中主要的轮作模式之一进行推广. 相似文献
8.
Granular acid-activated neutralized red mud (AaN-RM) has been successfully prepared with good chemical stability and physical strength. However, its potential for industrial application remains unknown. Therefore, the performance of granular AaN-RM for phosphate recovery in a fixed-bed column was investigated. The results demonstrated that the phosphate adsorption performance of granular AaN-RM in a fixed-bed column was affected by various operational parameters, such as the bed depth, flow rate, initial solution pH and initial phosphate concentration. With the optimal empty-bed contact time (EBCT) of 24.27 min, the number of processed bed volumes and the phosphate adsorption capacity reached 496.95 and 84.80 mg/g, respectively. Then, the saturated fixed-bed column could be effectively regenerated with a 0.5 mol/L HCl solution. The desorption efficiency remained as high as 83.45% with a low weight loss of 3.57% in the fifth regeneration cycle. In addition, breakthrough curve modelling showed that a 5-9-1 feed-forward artificial neural network (ANN) could be effectively applied for the optimization of the fixed-bed adsorption system; the coefficient of determination (R2) and the root mean square error (RMSE) evaluated on the validation-testing data were 0.9987 and 0.0183, respectively. Therefore, granular AaN-RM fixed-bed adsorption exhibits promising potential for phosphate removal and recovery from polluted water. 相似文献
9.
Peng Du Jianguo Liu Huaqiao Gui Jiaoshi Zhang Tongzhu Yu Jie Wang Yin Cheng Yihuai Lu Yawei Yao Qiang Fu ChihChieh Chen 《环境科学学报(英文版)》2020,32(1):238-249
PM_(2.5) separator directly affects the accuracy of PM_(2.5) sampling.The specification testing and evaluation for PM_(2.5) separator is particularly important,especially under China's wide variation of terrain and climate.In this study,first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM_(2.5) separators.A uniform mixing chamber was developed to make particles mix completely.The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%,and the particle size distribution obeyed logarithmic normal distribution with an R~2 of 0.996.The flow rate deviation between the measurement and the set point flow rate agreed to within ± 1.0% in the range of -40 to 50℃.Secondly,the separation,flow and loading characteristics of three cyclone separators(VSCC-A,SCC-A and SCC112) were evaluated using this system.The results showed that the 50% cutoff sizes(D_(50)) of the three cyclones were 2.48,2.47 and 2.44 μm when worked at the manufacturer's recommended flow rates,respectively.The geometric standard deviation(GSD) of the capture efficiency of VSCCA was 1.23,showed a slightly sharper than SCC-A(GSD = 1.27),while the SCC112 did not meet the relevant indicator(GSD = 1.2 ± 0.1) with a GSD = 1.44.The flow rate and loading test had a great effect on D_(50),while the GSD remained almost the same as before.In addition,the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test. 相似文献
10.
Juan Huang Jun Xiao Yang Guo Wenzu Guan Chong Cao Chunni Yan Mingyu Wang 《环境科学学报(英文版)》2020,32(1):319-330
Silver nanoparticles(AgNPs) have been widely used in many fields,which raised concerns about potential threats to biological sewage treatment systems.In this study,the phosphorus removal performance,enzymatic activity and microbial population dynamics in constructed wetlands(CWs) were evaluated under a long-term exposure to Ag NPs(0,50,and 200 μg/L) for 450 days.Results have shown that Ag NPs inhibited the phosphorus removal efficiency in a short-term exposure,whereas caused no obviously negative effects from a long-term perspective.Moreover,in the coexisting CW system of Ag NPs and phosphorus,competition exhibited in the initial exposure phase,however,cooperation between them was observed in later phase.Enzymatic activity of acid-phosphatase at the moderate temperature(10–20°C) was visibly higher than that at the high temperature(20–30℃) and CWs with Ag NPs addition had no appreciable differences compared with the control.High-throughput sequencing results indicated that the microbial richness,diversity and composition of CWs were distinctly affected with the extension of exposure time at different Ag NPs levels.However,the phosphorus removal performance of CWs did not decline with the decrease of polyphosphate accumulating organisms(PAOs),which also confirmed that adsorption precipitation was the main way of phosphorus removal in CWs.The study suggested that Ag NPs and phosphorus could be removed synergistically in the coexistence system.This work has some reference for evaluating the influences of Ag NPs on the phosphorus removal and the interrelation between them in CWs. 相似文献