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1.
Rudra P. Pradhan Mahendhiran S. Nair Mak B. Arvin John H. Hall 《Natural resources forum》2023,47(3):435-483
This article postulates strong endogenous relationships in lower income countries between institutional quality, financial development and sustained economic growth. These associations were investigated using the vector-error correction model (VECM) and Granger causality method for a sample of 79 countries from 2005 to 2022. The findings show that (1) these variables reinforce each other in the short run. (2) In the long run, both institutional quality and financial development can fuel economic growth. (3) The positive effect of institutional quality on economic growth is greater than that of financial development. Policy implications of these findings are that careful attention should be paid to co-development policies to enhance the institutional quality and the financial system in these economies. Policies should also consider economic growth strategies to enable sustainable economic growth rates. 相似文献
2.
工业用地供应行为的演化是工业经济发展的重要体现,分析工业用地供应规模的时空变化特征,有利于推进土地供给侧结构性改革,促进工业高质量发展,优化国土空间格局.基于重庆市2009~2018年工业用地供应公告数据,建立重庆市工业用地供应数据库,运用基尼系数、核密度分布、冷热点分析和趋势面分析方法,分析重庆市工业用地供应规模的时空变化规律.结果 表明:(1)重庆市工业用地供应规模总体上处于波动下降趋势,供应的区位呈现较为明显的东北-西南方向分布.区位基尼系数具有波动性特征,市域和分区都在空间分布不均衡和均衡间反复.(2)工业用地供应点规模呈现出“主环-斑点”式空间布局模式,高密度核心逐渐向主城区中心聚集.供应规模的热点区县在主城区的东西两侧变动,冷点区集中在渝东北角.(3)重庆市的中心城区及其西部和南部具有较大的工业用地供应规模,为建设成渝地区双城经济圈奠定了较好基础. 相似文献
3.
Ümit H. Kaynar Seda Çınar Sermin Çam Kaynar Mehmet Ayvacıklı Tülin Aydemir 《Journal of Polymers and the Environment》2018,26(6):2300-2310
Nano-ZnO-chitosan bio-composite beads were prepared for the sorption of \({\text{UO}}_{2}^{{2+}}\) from aqueous media. The resulting nano-ZnO/CTS bio-composite beads were characterized by TEM, XRD etc. The sorption of \({\text{UO}}_{2}^{{2+}}\) by bio-composite beads was optimized using RSM. The correlation between four variables was modelled and studied. According to RSM data, correlation coefficients (R2?=?0.99) and probability F-values (F?=?2.24?×?10??10) show that the model fits the experimental data well. Adsorption capacity for nano-ZnO/CTS bio-composite beads was obtained at 148.7 mg/g under optimum conditions. The results indicate that nano-ZnO/CTS bio-composite beads are appropriate for the adsorption of \({\text{UO}}_{2}^{{2+}}\) ions from aqueous media. Also, the suitability of adsorption values to adsorption isotherms was researched and thermodynamic data were calculated. 相似文献
4.
Helena Wedin Ellinor Niit Zaheer Ahmad Mansoor Anna Rúna Kristinsdottir Hanna de la Motte Christina Jönsson Åsa Östlund Christofer Lindgren 《Journal of Polymers and the Environment》2018,26(9):3603-3612
The chemical recycling of cellulosic fibres may represent a next-generation fibre–fibre recycling system for cotton textiles, though remaining challenges include how to accommodate fibre blends, dyes, wrinkle-free finishes, and other impurities from finishing. These challenges may disrupt the regeneration process steps and reduce the fibre quality. This study examines the impact on regenerated viscose fibre properties of a novel alkaline/acid bleaching sequence to strip reactive dyes and dimethyloldihydroxyethyleneureas (DMDHEU) wrinkle-free finish from cotton textiles. Potentially, such a bleaching sequence could advantageously be integrated into the viscose process, reducing the costs and environmental impact of the product. The study investigates the spinning performance and mechanical properties (e.g., tenacity and elongation) of the regenerated viscose fibres. The alkaline/acid bleaching sequence was found to strip the reactive dye and DMDHEU wrinkle-free finish from the cotton fabric, so the resulting pulp could successfully be spun into viscose fibres, though the mechanical properties of these fibres were worse than those of commercial viscose fibres. This study finds that reactive dyes and DMDHEU wrinkle-free finish affect the viscose dope quality and the regeneration performance. The results might lead to progress in overcoming quality challenges in cellulosic chemical recycling. 相似文献
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大九湖是南水北调中线工程的重要水源涵养地之一。为了解实施生态修复工程后浮游动物群落结构特征及水质污染情况,于2014年11月(枯水期)、2015年5月(平水期)和9月(丰水期)进行了3次采样调查。研究表明:共检出后生浮游动物36种,其中桡足类2种、枝角类5种和轮虫29种,轮虫丰度在3次采样中均占总丰度的80%以上,仅有的几种枝角类和桡足类也是小型种类或以幼体为主。11月优势种是寡污-β中污型-螺形龟甲轮虫(Keratella cochlearis)和晶囊轮虫(Asplachna sp.);5月优势种为寡污-β中污和β中污型-螺形龟甲轮虫、迈氏三肢轮虫(Filinia maior)、无棘螺形龟甲轮虫(Keratella cochlearis tecta)、广生多肢轮虫(Polyarthra vulgaris)和萼花臂尾轮虫(Brachionus calyciflorus);9月优势种是β-中污型-裂足臂尾轮虫(Brachionus diversicornis)、迈氏三肢轮虫和剪形臂尾轮虫(Brachionus forficula)。冗余分析(RDA)表明高锰酸盐指数(CODMn)是影响后生浮游动物污染类型分布的最关键环境因子。
关键词: 大九湖;后生浮游动物;污染类型;高山湿地湖泊 相似文献
7.
David M. Lapola José Maria C. da Silva Diego R. Braga Larissa Carpigiani Fernanda Ogawa Roger R. Torres Luis C. F. Barbosa Jean P. H. B. Ometto Carlos A. Joly 《Conservation biology》2020,34(2):427-437
Brazil hosts the largest expanse of tropical ecosystems within protected areas (PAs), which shelter biodiversity and support traditional human populations. We assessed the vulnerability to climate change of 993 terrestrial and coastal-marine Brazilian PAs by combining indicators of climatic-change hazard with indicators of PA resilience (size, native vegetation cover, and probability of climate-driven vegetation transition). This combination of indicators allows the identification of broad climate-change adaptation pathways. Seventeen PAs (20,611 km2) were highly vulnerable and located mainly in the Atlantic Forest (7 PAs), Cerrado (6), and the Amazon (4). Two hundred fifty-eight PAs (756,569 km2), located primarily in Amazonia, had a medium vulnerability. In the Amazon and western Cerrado, the projected severe climatic change and probability of climate-driven vegetation transition drove vulnerability up, despite the generally good conservation status of PAs. Over 80% of PAs of high or moderate vulnerability are managed by indigenous populations. Hence, besides the potential risks to biodiversity, the traditional knowledge and livelihoods of the people inhabiting these PAs may be threatened. In at least 870 PAs, primarily in the Atlantic Forest and Amazon, adaptation could happen with little or no intervention due to low climate-change hazard, high resilience status, or both. At least 20 PAs in the Atlantic Forest, Cerrado, and Amazonia should be targeted for stronger interventions (e.g., improvement of ecological connectivity), given their low resilience status. Despite being a first attempt to link vulnerability and adaptation in Brazilian PAs, we suggest that some of the PAs identified as highly or moderately vulnerable should be prioritized for testing potential adaptation strategies in the near future. 相似文献
8.
Ling R. Zeng Li H. Shi Xin G. Meng J. Xu Gui F. Jia T. Gui 《Journal of environmental science and health. Part. B》2019,54(4):317-325
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
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Journal of Material Cycles and Waste Management - Material flow analysis (MFA) is a well-established tool for supporting decisions on nutrient management. This paper shows the importance of the... 相似文献