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291.
The present study explores how oil and gas companies use Facebook to communicate about community-supporting initiatives and engage stakeholders. Drawing from the company–cause fit and social interactivity literature, we examined the type of message and the language used in company Facebook posts to elicit stakeholder engagement, as measured by the number of likes, shares, and comments. We content analyzed 953 Facebook posts from 12 companies featured on Oil & Gas Journal’s top 50-company list. The results showed that, although oil and gas companies are posting about their CSR-related efforts on Facebook, their lack of two-way messaging and interactive language use are not effectively engaging stakeholders. In terms of theory, this study advances company–cause fit and interactive studies by applying them to the oil and gas industry. In terms of practice, the results highlight the importance of using diverse messaging and interactive language when utilizing Facebook to engage stakeholders.  相似文献   
292.
Alternative and renewable fuels have numerous advantages compared with fossil fuels as they are renewable and biodegradable, besides providing food and energy security and foreign exchange savings and addressing environmental and socio-economic issues. Therefore, these renewable fuels can be used predominantly in compression ignition (CI) engines for transportation purposes and power generation applications. Today, the use of biomass-derived producer gas is more relevant for addressing rural power generation and is also a promising technique for controlling both NOx and soot emission levels. Although a producer gas–biodiesel-operated dual-fuel diesel engine exhibits lower performance, they are independent from the use of fossil fuels. The lower performance of the engine could be due to the slow-burning and lower calorific value of producer gas. For this purpose, exhaustive experiments on the use of Honge oil methyl ester (HOME)–producer gas in a dual-fuel CI engine were carried out for the improvement of its fuel efficiency. This paper presents the effect of the compression ratio (CR) on the performance, combustion and exhaust emission characteristics of a single-cylinder, four-stroke, direct injection stationary diesel engine operated using HOME and producer gas in a dual-fuel mode. The results indicated that the HOME–producer gas combination exhibited lower brake thermal efficiency (BTE) with comparable emission levels with the diesel–producer gas combination at different CRs. Comparative measures of BTE, peak pressure, pressure–crank angle variation, heat release rate, smoke opacity, and hydrocarbon (HC), carbon monoxide (CO) and nitric oxide (NOx) emission levels are presented and analysed.  相似文献   
293.
The cement industry is one of the most energy-intensive industries consuming 4 GJ/ton of cement, i.e. 12–15% of the energy use in total industry. Energy cost accounts for 30% of the total cost of cement production. Seventy-five per cent of this energy is due to the thermal energy for clinker production. It is also found that 35% of this supplied thermal energy is lost in flue gas streams. Most modern kilns use pet coke or coal as their primary fuel. Instead, the municipal waste in landfills offer a cheap source of energy and reduce the environmental effects of dumping solid waste. The calcination and drying processes and the kiln need large quantities of thermal energy. About 40% of the total energy input is lost in the hot flue gases and cooling the stack plus the kiln shell. Hence, it is suitable to use an organic Rankine cycle (ORC) to recover the exhaust energy from the kiln. Alternatively, a 15 MW gas turbine engine combined with a steam turbine could be utilized. It was found that ORC produces 5 MW with a capital cost recovery period of 1.26 years. However, the gas turbine combined system produces 21.45 MW with a maximum recovery period of 2.66 years.  相似文献   
294.
In recent years, organizations are becoming environment conscious due to stringent laws, competitive advantages and increasing awareness of customers. They are integrating environmental practices into their operations to curb carbon emissions. Regulatory bodies are also imposing carbon policies to check emission. In this paper, we developed three models considering three carbon policies (I. carbon tax, II. strict cap and III. cap-and-trade) and have determined the optimal order quantity and number of shipments for a two-echelon supply chain. The objective is to minimize the total supply chain cost which comprises the ordering, setup, production, inventory holding and transportation costs. In Model I tax on carbon emissions has been included in the cost function; in Model II we have considered a strict carbon cap on the total carbon emission; and in Model III trading price of carbon is included in the cost function. A numerical study is given to illustrate the solution procedure. Further, sensitivity analyses are performed to examine the impact of the various parameters on the total cost and total emission.  相似文献   
295.
Does the state of the economy condition public concern for the environment? Scholars have long argued that environmental preferences decline during economic downturns as individuals prioritize short-term economic needs over longer-term environmental concerns. Yet, this assumption has rarely been subjected to rigorous empirical scrutiny at the individual level. The presumed link between economic and environmental preferences is revisited, using the first individual-level opinion panel (n = 1043) of US climate attitudes, incorporating both self-reported and objective economic data. In contrast with prior studies that emphasize the role of economic downturns in driving environmental preference shifts, using a stronger identification strategy, there is little evidence that changes in either individual economic fortunes or local economic conditions are associated with decreased belief that climate change is happening or reduced prioritization of climate policy action. Instead, the evidence suggests that climate belief declines are associated with shifting political cues. These findings have important implications for understanding the dynamics of political conflict over environmental policy globally.  相似文献   
296.
China’s counterpart assistance policy is of vital importance in providing guidance for emergency management and post-disaster reconstruction. However, the amount of assistance that partner provinces should provide as well as the criteria that partners should abide by in offering counterpart assistance remain a main challenge. The goal of this research is to fill this gap by proposing a new framework consisting of an interregional input–output (IRIO) model and a resilience index. Subsequently, the indirect economic loss is obtained by utilizing the index system of provincial economic resilience assessments, with measures of indirect economic loss developed from the IRIO. Furthermore, to examine the internal validity and systematic error, the reliability of the adopted models, the calculation methods, and the index systems are investigated. To assess the external validity of the proposed measures and resilience index of the framework, data from the 2008 Wenchuan Earthquake are applied for estimating parameter values of the framework, and a follow-up investigation was conducted for examining the fairness and enhanced effectiveness of the new counterpart assistance criteria. In summary, this paper attempts to present some new ideas about the analysis of economic motivations of mutual aid and the improvement of the counterpart assistance policy.  相似文献   
297.
A polyvinylidene fluoride-based membrane bearing the diethylenetriaminepentaacetic acid chelating group was employed to recover Cu(II) from the Cu(II)-ethylenediaminetetraacetic acid complex aqueous solution. Effects of Ca(II), Fe(II), and Fe(III) on Cu(II) uptake were investigated by static batch adsorption tests and dynamic adsorption filtration. Isotherms, kinetics, and breakthrough curves of Cu(II) uptakes in the presence of the three cations at concentrations of 1 mmol L?1 were elucidated. The three cations showed a positive effect on the Cu(II) uptake; the stimulative roles were in the order of Fe(III) > Fe(II) > Ca(II). They did not alter the adsorption behavior of the membrane; adsorption isotherms and kinetics could be described by Langmuir and Lagergren second-order models, and Cu(II) adsorption was a spontaneous and exothermic process. The presence of Ca(II), Fe(II), and Fe(III) increased the sorption capacity of the membrane stack by 1.3, 1.9, and 3 times. Breakthrough time and the exhaustion time of membrane stacks were also extended.  相似文献   
298.
Halogenated phenols are industrial pollutants which may cause serious damage to the environment. In this work, a two-dimensional (2D) and two three-dimensional (3D) quantitative structure–activity relationship models for the toxicity prediction of halogenated phenols in Tetrahymena were developed. The structural factors that mainly influence toxicity were explored, agreeing with previously reported data. The results obtained with the 3D model were in agreement with those obtained with the 2D model. According to our findings, several new molecules with different predicted activities were designed.  相似文献   
299.
Engaging individuals in pro-environmental behaviours is critical to addressing today’s environmental challenges. This study examines how conditions – or an individual’s context – influence action. Through semi-structured narrative interviews and document analysis, we examined the influence of conditions in five individual cases involving attempted change in personal transportation behaviour. The cases, studied over the course of one year, are derived from participants in a sustainability institute, representing a range of attempted behaviours, and highlight numerous potential barriers to desired pro-environmental behaviours. We found that the degree of engagement with sustainable transportation primarily was influenced by the amount and intensity of supportive conditions relative to barriers. Participants who successfully engaged in their desired transportation-related pro-environmental behaviours experienced physical, social, and learning conditions that promoted competence and satisfaction. We discuss the implications for designing interventions that encourage pro-environmental behaviours.  相似文献   
300.
A stochastic and fuzzy chance-constrained programming (SFCCP) model was developed in this study for supporting energy–environment management in the city of Beijing, China. SFCCP was capable of tackling the variables in constraints as fuzzy random variables, which were integration of randomness and vagueness. SFCCP was applied to an energy–environment management system in the city of Beijing. The study results indicated that SFCCP was useful in helping decision makers gain in-depth insights into proposed management system and establish environment-friendly energy allocation alternatives. The application of SFCCP is expected to provide a good demonstration to energy–environment management problems under complex uncertainties.  相似文献   
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