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To study mitigation and adaptation to climate change, social scientists have drawn on different approaches, particularly sociological approaches to the future and comparative history of past societies. These two approaches frame the social and temporal boundaries of decision-making collectivities in different ways. A consideration of the responses to climate variability in three historical cases, the Classic Maya of Mexico and Central America, the Viking settlements in Greenland, and the US Dust Bowl, shows the value of integrating these two approaches.  相似文献   
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The biosorption potential of processed walnut shell for Pb(II) and Cd(II) ions from aqueous solutions was explored. The effects of pH, contact time, initial ion concentration, and amount of dried adsorbent were studied in batch experiments. The maximum adsorption was achieved within the pH range 4.0–6.0. The equilibrium data were well fitted by the Langmuir isotherm model. The maximum monolayer adsorption capacities were found to be 32?g?kg?1 and 11.6?g?kg?1 for Pb(II) and Cd(II) ions, respectively. Kinetic data were best described by the pseudo-second-order model. The structural features of the adsorbent were characterized by Fourier transform infrared spectroscopy, which confirmed the involvement of hydroxyl (–OH), carboxyl (–COO), and carbonyl (C=O) groups in metal sorption. This readily available adsorbent is efficient in the uptake of Pb(II) and Cd(II) ions from an aqueous solution and could be used for the treatment of wastewater streams bearing these metal ions.  相似文献   
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A novel nanocomposite based on incorporation of multiwalled carbon nanotubes (MWCNTs) in polyvinyl chloride (PVC) was prepared. Proposed nanocomposite was coated on stainless steel wire by deep coating. Composition of nanocomposite was optimized based on results of morphological studies using scanning electron microscopy. The best composition (83% MWCNTs:17% PVC) was applied as a solid phase microextraction fiber. Complex mixture of aromatic (BTEX) and aliphatic hydrocarbons (C5–C34) were selected as model analytes, and performance of proposed fiber in extraction of the studied compounds from water and soil samples was evaluated. Analytical merits of the method for water samples (LODs = 0.10–1.10 ng L−1, r2 = 0.9940–0.9994) and for soil samples (LODs = 0.10–0.77 ng kg−1, r2 = 0.9946–0.9994) showed excellent characteristics of it in ultra trace determination of petroleum type environmental pollutants. Finally, the method was used for determination of target analytes in river water, industrial effluent and soil samples.  相似文献   
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Due to the increasingly serious environmental problems presented by waste tires, the feasibility of using elastic and flexible tire-rubber particles as aggregate in concrete is investigated in this study. Tire-rubber particles composed of tire chips, crumb rubber, and a combination of tire chips and crumb rubber, were used to replace mineral aggregates in concrete. These particles were used to replace 12.5%, 25%, 37.5%, and 50% of the total mineral aggregate's volume in concrete. Cylindrical shape concrete specimens 15 cm in diameter and 30 cm in height were fabricated and cured. The fresh rubberized concrete exhibited lower unit weight and acceptable workability compared to plain concrete. The results of a uniaxial compressive strain control test conducted on hardened concrete specimens indicate large reductions in the strength and tangential modulus of elasticity. A significant decrease in the brittle behavior of concrete with increasing rubber content is also demonstrated using nonlinearity indices. The maximum toughness index, indicating the post failure strength of concrete, occurs in concretes with 25% rubber content. Unlike plain concrete, the failure state in rubberized concrete occurs gently and uniformly, and does not cause any separation in the specimen. Crack width and its propagation velocity in rubberized concrete are lower than those of plain concrete. Ultrasonic analysis reveals large reductions in the ultrasonic modulus and high sound absorption for tire-rubber concrete.  相似文献   
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Environmental Science and Pollution Research - Reliable and accurate prediction model capturing the changes in solar radiation is essential in the power generation and renewable carbon-free energy...  相似文献   
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This study is trying to explore the relationship between corporate social responsibility (CSR) disclosures and financial performances (FP) through mediating role of the employee productivity (EP). This study classifies the CSR performances into four contexts, for instance, environment social governance (ESG), environmental improvement activity scores of CSR, social welfare activity score, and governance structure improvement score. The banking performance is classified into three different aspects such as returns on assets (ROA), returns on equity (ROE), and nominal interest margin profit (NIMP). The study covers the data set start from 2008 to 2019 regarding thirty commercial banks of China. The study uses the linear, non-linear, and quadratic techniques to explore the association between CSR disclosures and banking performances. The linear model result shows that the governance score is significant influencing the banking performance. Moreover, the employee productivities are also positive significant affecting the baking performances. The non-linear results of model show that composite score of ESG with employee productivity has significant influence on financial performance.

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Environmental Science and Pollution Research - The discovery of microRNAs (miRNAs) 20 years ago has advocated a new era of “small molecular genetics.” About 2000 miRNAs are present that...  相似文献   
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