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991.
物流业快速发展带来的碳排放问题已引起有关部门的高度重视。基于1995—2012年河南省物流企业的统计数据,运用消耗能源折算法对河南省物流行业的碳排放总量和碳排放强度进行了估算,构建了河南省物流企业碳排放的EKC模型曲线,分析了河南省物流企业碳排放的发展历程和规律特征,预测了河南省物流企业碳排放的发展阶段和未来趋势。研究表明:河南省物流企业的碳排放量正处于继续上升的阶段,碳排放强度整体稳中有降,物流碳排放与行业发展呈现出反"N"型的曲线结构,如果加强环境管制、积极发展"低碳物流"将促进碳排放"拐点"提前出现,可实现经济发展与环境保护的"双赢"。 相似文献
992.
马云 《中国环境管理干部学院学报》2015,(2):31-34
"环境污染第三方治理"是党和政府顺应时代发展提出的治污新模式,这为我国水污染的治理指明了新方向。水污染第三方治理机制不仅在制度上是个创新,在法律层面也提出了新的要求,特别是在规制第三方的刑事责任方面。要明确第三方成为新的责任主体,在认定责任的归责原则上适用相对严格责任原则,在责任承担的具体方式上适用"双罚制"和罚金刑,为水污染第三方治理机制的引入奠定良好的法律基础。 相似文献
993.
A double‐edged sword: The moderating role of conscientiousness in the relationships between work stressors,psychological strain,and job performance 下载免费PDF全文
Although conscientiousness was commonly viewed as a type of personal resource to help individuals reduce strain or mitigate the impacts of stressors, empirical research demonstrated mixed results. Based on the personal resource allocation perspective, we posited that rather than functioning as personal resource per se, conscientiousness may act as a key factor influencing how individuals allocate their personal resources. The current study examined the moderating roles of conscientiousness in the relationships that work stressors (i.e., challenge stressors and hindrance stressors) have with employee psychological strain and job performance by using multi‐source, time‐lagged data collected from 250 employees working at two companies. The results showed that both challenge stressors and hindrance stressors were positively related to psychological strain. Conscientiousness moderated the relationships between both stressors and psychological strain, such that the positive relationships were stronger for individuals with high conscientiousness. Conscientiousness also moderated the relationship between challenge stressors and performance, such that the relationship was positive for individuals with high conscientiousness but negative for those with low conscientiousness. Altogether, the findings suggest that conscientiousness acts as a double‐edged sword that both promotes performance and exacerbates the stress reaction of employees when they are confronted with stressful situations. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
994.
快速准确地从灾后影像中提取出受灾区域对于灾后救援具有重要意义。鉴于现有提取方法过度依赖滑坡在影像中的光学、纹理等特征的问题,研究了一种结合独立成分分析(ICA)与最小噪声比率变换(MNF)的变化检测方法,以单一时相的影像为基础,运用基于负熵最大化的Fast-ICA算法分离出两个时相影像相互正交的独立成分,并构建对应独立成分的差异影像,最后用最小噪声比率变换实现分布于各个差异影像上变化信息的集中,应用直方图阈值法得到了最终的滑坡灾害信息。选取了滑坡灾害前后两时相的高分辨率遥感影像数据进行实验,结果证实了方法的可行性。 相似文献
995.
雌激素等内分泌干扰物在水体中普遍存在,其在再生水中的存在以及在水体中的迁移转化会产生潜在的健康和生态风险。光降解是水体中雌激素消除的主要途径之一,水体中共存的无机离子及有机质等对雌激素的光解存在不同的影响。对高碑店湖再生水体中雌激素的污染状况进行了调查,结果显示表层水中天然雌激素雌酮(E1)和人工合成雌激素17α-乙炔基雌二醇(EE2)的浓度最高。在模拟太阳光照射条件下对E1在水溶液中的降解规律及影响因素进行了研究,发现在模拟1 SUN的光密度条件下,15 min时E1降解率可达85%(C0=5μg·L-1),而氨氮对E1的光降解存在一定的抑制作用,并且抑制作用随着氨氮的升高而变大。与纯水系统相比,高碑店湖表层水基质中E1的光降解速率较低,说明整体上氨氮、HCO-3、浊度等因素对E1光降解产生的抑制作用占主导。对雌酮及其降解产物进行了红外光谱分析,结果显示1 720 cm-1对应的C=O键特征峰在光照时间为0、10和20 min样品中的强度逐渐减弱,而2 854 cm-1和2 925 cm-1对应的脂肪碳的C-H键特征峰先增强后减弱,可能是因为E1结构中的C-C=O发生了反应生成了C=C-OH,而随着反应的继续,C=C也被进一步氧化,但降解产物的结构需要进一步研究推断。随着E1的光降解,E1水溶液的内分泌干扰活性逐渐下降,氨氮虽然对E1的光降解有一定的抑制作用,但随着降解反应的进行E1水溶液的内分泌干扰活性依然呈下降趋势。 相似文献
996.
997.
Nucleic acids and their analogues are getting more and more attention. Metal-mediated base pairs as a kind of simple and functionalized nucleic acids in special positions have widened the scope of application of functional nucleic acids and their analogues. In this type of base pairs, the representative is the interaction between metal ions and pyrimidine bases, especially the research on thymine-Hg2+-thymine (T-Hg2+-T) and cytosine-Ag+-cytosine (C-Ag+-C) base pairs. This review summarizes the structure and mechanism of metal-mediate pyrimidine base pairs as well as the application in the biochemical analysis. It explores the mode and ratio of coordination between metal ions and base pairs, the effects on the stability of DNA helical structure, the related crystal structure and the three-dimensional configuration information in the DNA helix. The analytical application mainly includes various probes of metal ions, small molecules, protein and the detection of single nucleotide polymorphism. Among them the most widely used metal ions detection, and its combination with spectrum technology, visualization and amplification technology greatly promoted the rapid development of sensitive detection technology. In further studies, it is necessary to reveal the mechanism of interaction between T-Hg2+-T and C-Ag+-C, and more attention should be paid to combining of T-Hg2+-T and C-Ag+-C base pairs with other new technologies. The scope of practical application should also be further extended. 相似文献
998.
贵阳市环境空气质量预报预警系统建立的探讨 总被引:1,自引:0,他引:1
分析了贵阳市空气质量预报中污染物、地形及下垫面、植被等关键影响因素。提出了贵阳市环境空气质量预报预警系统的整体架构,分别对排放源监测与管理系统、环境空气质量预报系统和污染预警与控制决策支持系统等三个核心部分进行阐述,进一步提出了贵阳市大气污染防控措施及防控机制。 相似文献
999.
We investigated the efficiency and kinetics of the degradation of soluble dyes over the p H range 5.0–9.0 using a method employing microwave radiation in combination with nanoscale zero-valent iron(MW–n ZVI). The n ZVI particles(40–70 nm in diameter) were prepared by a liquid-phase chemical reduction method employing starch as a dispersant.Compared to the removal of Solvent Blue 36 and Reactive Yellow K-RN using only n ZVI,more rapid and efficient dye removal and total organic carbon removal were achieved using MW–n ZVI. The dye removal efficiency increased significantly with decreasing p H, but was negligibly affected by variation in the microwave power. The kinetics of dye removal by MW–n ZVI followed both an empirical equation and the pseudo first-order model, while the kinetics of dye removal using n ZVI could only be described by an empirical equation. It was also concluded that microwave heating of the dye solutions as well as acceleration of corrosion of n ZVI and consumption of Fe(II) were possible reasons behind the enhanced dye degradation. 相似文献
1000.