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691.

The formation of gas hydrates is a major issue during the operation of oil and gas pipelines, because gas hydrates cause plugging, thereby disrupting the normal oil and gas flows. A solution is to inject gas hydrate inhibitors such as ionic liquids. Contrary to classical inhibitors, ionic liquids act both as thermodynamic inhibitors and hydrate inhibitors, and as anti-agglomerates. Imidazolium-based ionic liquids have been found efficient for the inhibition of CO2 and CH4 hydrates. For CO2 gas hydrates, N-ethyl-N-methylmorpholinium bromide showed an average depression temperature of 1.72 K at 10 wt% concentration. The induction time of 1-ethyl-3-methyl imidazolium bromide is 36.3 h for CO2 hydrates at 1 wt% concentration. For CH4 hydrates, 1-ethyl-3-methyl-imidazolium chloride showed average depression temperature of 4.80 K at 40 wt%. For mixed gas hydrates of CO2 and CH4, only quaternary ammonium salts have been studied. Tetramethyl ammonium hydroxide shifted the hydrate liquid vapour equilibrium to 1.56 K at 10 wt%, while tetrabutylammonium hydroxide showed an induction time of 0.74 h at 1 wt% concentration.

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692.
Environmental Science and Pollution Research - Water contaminated with phosphorus needs to be managed efficiently to ensure that clean water sources will be preserved. Aquaculture plays an...  相似文献   
693.
Environmental Science and Pollution Research - Sentinel lymph node (SLN) sampling is important for evaluating the nodal stage of breast cancer when the axillary nodes are clinically free of...  相似文献   
694.
Environmental Science and Pollution Research - The integration of Industry 4.0 (I4.0) has emerged as an innovative paradigm for industrial firms contemplating environmental and economic issues....  相似文献   
695.
Environmental Science and Pollution Research - Sugar industry produces a variety of organic byproducts causing disposal as well as environmental issues. This study investigated the safe use of...  相似文献   
696.
Environmental Science and Pollution Research - In recent years, environmental change has arisen as a ubiquitous problem and gained environmentalist’s attention across the globe due to its...  相似文献   
697.
Environmental Science and Pollution Research - As discharging oily wastewater from industries to the environment is a potential threat for the aquatic ecosystem, in this research, oil removal from...  相似文献   
698.
Environmental Science and Pollution Research - Developing land suitability models for strategically critical agricultural products to expand sustainable agricultural policies and sensitive...  相似文献   
699.
Environmental Science and Pollution Research - One of the major challenges faced by human society is the freshwater crisis and shortage of conventional energy. Solar still is considered as one of...  相似文献   
700.

Climate change in the global perspective has increased the occurrence of natural disasters, which subsequently decreased agricultural production and intensified the issue of food security. Developing countries, such as Pakistan, are facing severe food security issues, where most of the population still experiences poverty and hunger in their daily lives. Flood disasters ruin valuable land, cause agricultural production losses, and interrupt livelihood routines as expected household livelihood becomes more vulnerable. This research work focused on investigating the flood hazards vulnerability and risk of food security in the Bait community flood-prone areas of Punjab, Pakistan, with a broader aspect in contrast to previous research work. A constructed food security index composed of several IPCC and FAO factors with correlated dimensions of food security was used for the empirical estimation in this study. A composite food security index was developed through polychoric principal component analysis. To estimate the influence on the overall food security condition in the study area, a food security index was regressed on various independent variables. Estimates of the study indicated that three-fourths of household respondents in the study area are confronted with the issue of food security with changeable scale. Financing schemes, physical assets, and family type illustrated the positive influence on respondents’ food security level, whereas respondents suffering property losses owing to floods had a negative influence. The study findings suggested integrated strategies must be adopted to effectively deal with issues of food security in the scenario of increasing severity of flood disasters. Policymakers and disaster-concerned institutions need to develop disaster risk mitigation strategies by constructing new water reserves and clearing river encroachments to deal with flood disasters. Agricultural research and development authorities need to provide climate friendly seed varieties and promote particular food crops for flood prone areas to ensure food security and reduce livelihood vulnerability, specifically for the flood-prone communities.

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