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111.
Environmental Science and Pollution Research - Demand for renewable energy sources has increased significantly during the past 15–20 years. Due to this demand, one positive scenario...  相似文献   
112.
Environmental Science and Pollution Research - This paper investigates the effect of different categories of essential COVID-19 data from 2020 to 2021 towards stock price dynamics and options...  相似文献   
113.
Environmental Science and Pollution Research - In the contemporary era, it is evident that consumption-based carbon emissions (CCO2e), adjusted for international trade, are a more accurate and...  相似文献   
114.
Organic reactions in aqueous media are being developed because water is environmentally benign. The Horner–Wadsworth–Emmons reaction is a modified Wittig reaction for the synthesis of α,β-unsaturated ketones and other conjugated compounds. Here we prepared high molecular weight ketones by the Horner–Wadsworth–Emmons reaction of dimethyl-2-oxopropylphosphonate and various aldehydes in water at room temperature. The product was precipitated during the reaction process and was separated readily by a simple filtration in 90–99 % yield.  相似文献   
115.
As a result of human lifestyles and unsustainable consumption patterns, the environment continues to deteriorate and thus inhibit sustainable development. In order to curb this situation and promote a sustainable economy, one of the solution is to reduce conventional products consumption and shift to green products. Over the past 20 years, marketing managers keenly seek to understand the green market; however, inadequate information on how to promote consumers’ green behavioral intentions is slowing the growth of green markets and becomes a barrier for firms when developing segments and communicating strategies for effective promotion of green products in countries like Malaysia where the trend is fairly new. Therefore, this study attempts to examine the impact of environmental knowledge, cultural values, and environmental advertising and determine the moderating effect of income level, education level, and gender on consumers’ green purchase intentions. A survey was administered, and a total of 405 valid questionnaires were obtained. Structural equation modeling technique was used to evaluate the causal model by using SmartPLS 2.0 software. The finding results suggest that cultural values and environmental advertising are the main influences in building green purchase intentions, while environmental knowledge is not significantly related. The results also indicate that education level and gender have a significant positive moderation effect while income did not. This suggests that green purchase intentions’ motivational factors are greater among highly educated individuals, with females in particular. The discussions and implications of these findings are further elaborated.  相似文献   
116.
Concentrations of nine inorganic elements (Na, Zn, Ca, Fe, Ni, Mn, Cu, Cd and Al) in particulate matter (PM10) in the air of an equatorial urban coastal location during 2009 were studied during summer and winter monsoon seasons using high-volume sampling techniques. Atomic absorption spectrophotometry was used to analyse the samples. The concentrations of most inorganic elements were higher during summer than winter, except for Cu and Zn. The main inorganic elements in PM10 are Na, Zn and Ca. High concentrations of Na and Ca are due to marine aerosols. Analysis of enrichment factors showed that inorganic elements are from non-crustal sources. Cluster analysis identified five clusters in the summer and six in the winter: (1) PM10–Ni, (2) Zn–Na, (3) Fe–Cu–Ca–Cd, (4) Mn and (5) Al for summer; and (1) PM10, (2) Zn, (3) Fe–Ni, (4) Cu–Ca–Na–Cd, (5) Mn and (6) Al for winter. Combining both correlation and cluster analysis, it was found that Fe–Cu–Cd was from industry/vehicle emissions, Zn was from resuspended soil, Mn was from metallurgical processes, Ni was from a nearby power plant and Al was from crustal sources. Inorganic element concentrations could be a good indicator of local sources of PM10.  相似文献   
117.
This article reports a novel procedure to prepare pyrroles using a modification of the Paal–Knorr reaction. Water is a safe solvent meeting environmental considerations, but most organic substrates are not soluble in water. A possible solution to improve the solubility of substrates is the use of surface-active reagents that can form micelles. For instance, combined Lewis acid–surfactant catalyst acts both as a Lewis acid to activate the substrate molecules and as a surfactant to form emulsions in water. Here, we prepared and used aluminum tris(dodecyl sulfate)trihydrate to condense various amines to 2,5-hexadione at room temperature. The sole solid pyrrole was separated by a simple filtration. Our findings thus show a novel and improved modification of the Paal–Knorr reaction in terms of mild reaction conditions and clean reaction profiles, using a simple workup procedure and improved yields with excellent chemo-selectivity.  相似文献   
118.
Journal of Polymers and the Environment - The degradation behaviors of an amorphous and a semicrystalline PLA (i.e., aPLA and cPLA) with similar molecular weights are compared at elevated...  相似文献   
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120.
Variations in geo-environmental attributes differ strongly from those of urban anthropogenic structures. Similarly, these types of structures are self-directed and arranged and prone to abrupt process-related changes and modifications. Thus, there are many reasons why planned urbanization forms in association with disturbances in ecosystem mobility. The current research highlights these variations in the context of social–cultural assessments within the Jhelum River watershed, which strongly expresses urbanization structure development mechanisms. The climate ranges from semi-arid to subhumid subtropical and sub-mountainous climate, though the extreme temperatures may rise as high as 49.4°C in June and may drop as low as ?1.6°C in January. The rainfall is low in the southwest and gradually increases towards the northeast, whereas the Salt Range is the major topographic feature that controls climatic impacts and promotes sustainable development. Cross-disciplinary methods are adopted in this investigation to assess the social–ecological landscape system (SELS) in terms of its mobility and degree of urbanization. The Sustainable Development Goals of the 2030 Agenda recognize that human livelihoods and the management of natural resources cannot be addressed separately. Investing in the sustainability of mountain communities and ecosystem conservation and protection will provide benefits for humanity as a whole. It pertains to the commensurate development of the SELS and its response to interruptions. Thus, a reliable SWOT analysis for management approaches is introduced that may enable the development of competencies that promote and lead towards rapid improvements in the sustainability of retrograde urban infrastructure, including watersheds.  相似文献   
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