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111.
In this work, the effects of tool rotation and various intensities of external magnetic field on electrical discharge machining (EDM) performance have been studied. Experimental trials divided into three regimes of low energy regime, middle energy regime and high energy regime. The influences of process parameters were investigated on main outputs of material removal rate (MRR) and surface roughness (SR). In order to correlate the input parameters and output values two mathematical models were developed to predict the MRR and SR according to variations of discharge energy, magnetic field intensity and tool rotational speed. Results indicated that the applying a rotational magnetic field around the machining gap improves the MRR and SR. Combination of rotational magnetic field and rotary electrode increases the machining performance, in comparison of previous conditions. This is due to better flushing debris from machining gap. This work introduces a new method for improving the machining performance, in cost and time points of view.  相似文献   
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113.
API650-2008 is one of the prominent codes consisting of seismic specifications to design steel storage tanks for earthquakes resistance. In spite of the code's broad application, there are some failure modes such as slide bottom, elephant-foot buckling, sloshing and uplift needing more evaluation. In this paper, 161 existing tanks in an oil refinery complex have been classified into 24 groups and investigated using both API650-2008 rules and numerical FEM models. Failure modes and dynamic characteristics of studied models have been calculated by numerical FEM analysis and compared with code requirements. The results demonstrate that, in some cases, there are some imperfections in the code requirements that require further investigation.  相似文献   
114.
Environmental Science and Pollution Research - In this study, activated carbon and piperazine-modified activated carbon adsorbents were prepared and used for CO2 adsorption. The effect of various...  相似文献   
115.
Journal of Polymers and the Environment - Alzheimer’s disease is the most prevalent cause of dementia in aging people. 7-Methoxytacrine (7-MEOTA) is one of the approved drugs for the...  相似文献   
116.
Environmental Science and Pollution Research - This study aims to assess the trends in the incidence rate of neurological disorders in developed and developing countries worldwide during...  相似文献   
117.

There have been many studies on bio-inspired research, where biomimicry capabilities facilitating sustainable designs are in dearth. For a sustainable design, it is necessary to consider water efficiency, zero waste, thermal environment, and energy supply. This paper investigates how biomimicry is adopted in the sustainable design of buildings. A thorough content analysis of eight case studies focused on the built environment and how biomimicry integrated with the design of a building was executed. The selection of cases study was based on the concept of biomimicry by taking inspiration from nature and applying them in the everyday built environment. Thus, the building designs are more ecologically sustainable than conventional ones, where biomimicry approaches and principles are adopted. The findings suggest that the design of a building can inspire society with new ecological morals, where understanding of biological morphogenesis can inspire design to resolve challenges and essentially help create a healthy environment. Biomimicry harnesses and replicates the principles found in nature to create a built environment that benefits people and other living creatures and safeguards biodiversity. Thus, adopting biomimicry in designing a building will help to develop a culture of active environmental design.

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118.
Environmental Science and Pollution Research - In recent years, suppliers in developing countries face the challenge of their low technological and knowledge-related capabilities to enhance...  相似文献   
119.

The aim of this study was to investigate the lead (Pb)-induced lipid metabolism impairment and its amelioration using plant-based therapeutic interventions. Pb-induced hepatotoxicity can disturb the normal levels of natural antioxidant enzymes including glutathione (GSH) and superoxide dismutase (SOD) exerting a crucial impact on membrane unsaturated fatty acids (FA), hence leading to lipid peroxidation. Furthermore, Pb toxicity can also alter the regulation of various hormones involved in the synthesis of 3-hydroxy-methyl glutaryl CoA (HMG-CoA reductase), leading to an impairment in normal levels of serum cholesterol and other associated conjugated lipid molecules such HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol. In this study, the lipoprotein fractions, cholesterol, triglyceride (TGs) and biomarkers of liver functions were estimated by employing respective assay kits. The levels of antioxidant enzymes, FFAs and HMG-CoA reductase were determined by employing sandwich ELISA method. The administration of PbAc in experimental rats induced a significant disturbance in lipid profile (P < 0.05) accompanying a significant reduction in natural antioxidant defence system (P < 0.05). The significant alteration in the levels of serum antioxidant enzymes can lead to membrane lipid peroxidation that is reflected by a significantly (P < 0.05) high level of serum MDA in PbAc-induced experimental rats. However, the administration of resveratrol proved therapeutically effective in the treatment of Pb toxicity. Overall, the results of this study accompanying histopathological examination had proved the ameliorating effect of resveratrol in Pb-induced lipid metabolism impairment by adopting vitamin C as a standard therapeutic intervention.

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120.
Environmental Science and Pollution Research - The livelihoods of poor people living in rural areas of Indus Basin Irrigation System (IBIS) of Pakistan depend largely on irrigated agriculture....  相似文献   
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