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1.
Environmental Science and Pollution Research - The existing literature on the environmental Kuznets curve (EKC) fails to investigate the spatial attribute of the “pollution halo” effect...  相似文献   
2.
基于2005~2017年湖北省74个县域面板数据,构建基于交通权重的空间权重矩阵,利用空间杜宾模型,实证研究耕地利用转型影响农民增收的空间溢出效应,并进一步揭示该溢出效应呈现的具体规律与特征.研究表明:(1)耕地利用转型各形态和农民收入水平都具有显著的正向空间自相关性;(2)农民收入水平的空间自回归系数ρ为0.65,表明相邻县域农民增收存在正向空间溢出效应,即本县域农民收入增长1%,相邻县域农民收入将会增长0.65%;(3)相邻县域间的空间溢出效应主要靠耕地数量、农业劳动力和基础设施投入形态变化驱动,其中,农业劳动力形态变化产生的空间溢出效应占总效应的69%,耕地数量形态占15%,基础设施投入形态占12%.因此,应注意提升县域间耕地利用系统协同性,利用其空间溢出效应促进湖北省各县域共同发展、农民收入协同提高.  相似文献   
3.
Huang  Ying  Jiang  Qiongji  Yu  Xubiao  Gan  Huihui  Zhu  Xia  Fan  Siyi  Su  Yan  Xu  Zhirui  He  Cunrui 《Environmental science and pollution research international》2021,28(37):51251-51264
Environmental Science and Pollution Research - Trace copper ion (Cu(II)) in water and wastewater can trigger peroxymonosulfate (PMS) activation to oxidize organic compounds, but it only works under...  相似文献   
4.
Environmental Science and Pollution Research - The impact of high concentrations of air pollution on COVID-19 has been a major air quality and life safety issue in recent studies. This study aimed...  相似文献   
5.
针对2018年3月9—15日京津冀地区的一次空气重污染过程,进行了基于地基颗粒物激光雷达组网的星载-地基联合观测分析。颗粒物激光雷达观测到污染前期为局地污染累积过程,中期有明显的污染物区域传输过程,北京受太行山沿线城市污染输送影响较大。风廓线激光雷达观测结果表明:此次污染过程近地面主要为偏南风且风力较弱,冷空气到来时风向转为较强东北风,导致污染消散。微波辐射计观测到保定在污染过程中出现持续6 d的逆温层,同时在污染过程中近地面相对湿度较高,逆温层被打破后污染开始消散。在污染过程的各个阶段中,污染团的空间分布与变化特征均被很好地反映出来,可见地天联合观测对污染物的累积与输送研究有较大的意义,能对京津冀及周边地区的大气污染联防联控提供有力支持。  相似文献   
6.
Yan  Mi  He  Lei  Prabowo  Bayu  Fang  Zhumin  Lin  Jie  Xu  Zhang  Hu  Yanjun 《Journal of Material Cycles and Waste Management》2018,20(3):1594-1604
Journal of Material Cycles and Waste Management - Efforts to improve the performance of hydrothermal treatment (HT) in producing high-quality solid fuel from sewage sludge were carried out by...  相似文献   
7.
8.
This study evaluated the hydrolysis and photolysis kinetics of pyraclostrobin in an aqueous solution using ultra-high-performance liquid chromatography–photodiode array detection and identified the resulting metabolites of pyraclostrobin by hydrolysis and photolysis in paddy water using high-resolution mass spectrometry coupled with liquid chromatography. The effect of solution pH, metal ions and surfactants on the hydrolysis of pyraclostrobin was explored. The hydrolysis half-lives of pyraclostrobin were 23.1–115.5?days and were stable in buffer solution at pH 5.0. The degradation rate of pyraclostrobin in an aqueous solution under sunlight was slower than that under UV photolysis reaction. The half-lives of pyraclostrobin in a buffer solution at pH 5.0, 7.0, 9.0 and in paddy water were less than 12?h under the two light irradiation types. The metabolites of the two processes were identified and compared to further understand the mechanisms underlying hydrolysis and photolysis of pyraclostrobin in natural water. The extracted ions obtained from paddy water were automatically annotated by Compound Discoverer software with manual confirmation of their fragments. Two metabolites were detected and identified in the pyraclostrobin hydrolysis, whereas three metabolites were detected and identified in the photolysis in paddy water.  相似文献   
9.
Objectives: The accuracy of self-reported driving exposure has questioned the validity of using self-reported mileage to inform research questions. Studies examining the accuracy of self-reported driving exposure compared to objective measures find low validity, with drivers overestimating and underestimating driving distance. The aims of the current study were to (1) examine the discrepancy between self-reported annual mileage and driving exposure the following year and (2) investigate whether these differences depended on age and annual mileage.

Methods: Two estimates of drivers’ self-reported annual mileage collected during vehicle installation (obtained via prestudy questionnaires) and approximated annual mileage driven (based upon Global Positioning System data) were acquired from 3,323 participants who participated in the Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study.

Results: A Wilcoxon signed rank test showed that there was a significant difference between self-reported and annual driving exposure during participation in SHRP 2, with the majority of self-reported responses overestimating annual mileage the following year, irrespective of whether an ordinal or ratio variable was examined. Over 15% of participants provided self-reported responses with over 100% deviation, which were exclusive to participants underestimating annual mileage. Further, deviations in reporting differed between participants who had low, medium, and high exposure, as well as between participants in different age groups.

Conclusions: These findings indicate that although self-reported annual mileage is heavily relied on for research, such estimates of driving distance may be an overestimate of current or future mileage and can influence the validity of prior research that has utilized estimates of driving exposure.  相似文献   

10.
A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method was developed for the determination of thiamethoxam and its metabolite clothianidin in citrus (including the whole citrus, peel and pulp) and soil samples by liquid chromatography-tandem mass spectrometry. The sample was extracted with acetonitrile and purified with octadecylsilane. The detection limits of both compounds were 0.0001–0.0002?mg kg–1, while the limit of quantification of thiamethoxam was 0.002?mg kg–1 and the limit of quantitation of metabolites was 0.001?mg kg–1. The recovery was 70.37%–109.76%, with inter-day relative standard deviations (RSD) (n?=?15) values ≤9.46% for the two compounds in the four matrices. The degradation curve of thiamethoxam in whole citrus and soil was plotted using the first-order kinetic model. The half-life of the whole citrus was 1.9–6.2?days, and the half-life of the soil was 3.9–4.2?days. The terminal residue of thiamethoxam (the sum of thiamethoxam and clothianidin, expressed as thiamethoxam) was found to be concentrated on the peel. The final residual amount of thiamethoxam in the edible portion (pulp) was less than 0.061?mg kg–1. The risk quotient values were all below 1, indicating that thiamethoxam as a citrus insecticide does not pose a health risk to humans at the recommended dosage.  相似文献   
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