Appropriate assessment of firm sustainability facilitates actor-driven processes towards sustainable development. The methodology in this paper builds further on two proven methodologies for the assessment of sustainability performance: it combines the sustainable value approach with frontier efficiency benchmarks. The sustainable value methodology tries to relate firm performance to the use of different resources. This approach assesses contributions to corporate sustainability by comparing firm resource productivity with the resource productivity of a benchmark, and this for all resources considered. The efficiency is calculated by estimating the production frontier indicating the maximum feasible production possibilities. In this research, the sustainable value approach is combined with efficiency analysis methods to benchmark sustainability assessment. In this way, the production theoretical underpinnings of efficiency analysis enrich the sustainable value approach. The methodology is presented using two different functional forms: the Cobb–Douglas and the translog functional forms. The simplicity of the Cobb–Douglas functional form as benchmark is very attractive but it lacks flexibility. The translog functional form is more flexible but has the disadvantage that it requires a lot of data to avoid estimation problems. Using frontier methods for deriving firm specific benchmarks has the advantage that the particular situation of each company is taken into account when assessing sustainability. Finally, we showed that the methodology can be used as an integrative sustainability assessment tool for policy measures. 相似文献
Environmental Chemistry Letters - Because many engineered nanoparticles are toxic, there is a need for methods to fabricate safe nanoparticles such as plant-based nanoparticles. Indeed, plant... 相似文献
Covid-19 lockdowns have improved the ambient air quality across the world via reduced air pollutant levels. This article aims to investigate the effect of the partial lockdown on the main ambient air pollutants and their elemental concentrations bound to PM2.5 in Hanoi. In addition to the PM2.5 samples collected at three urban sites in Hanoi, the daily PM2.5, NO2, O3, and SO2 levels were collected from the automatic ambient air quality monitoring station at Nguyen Van Cu street to analyze the pollution level before (March 10th–March 31st) and during the partial lockdown (April 1st–April 22nd) with “current” data obtained in 2020 and “historical” data obtained in 2014, 2016, and 2017. The results showed that NO2, PM2.5, O3, and SO2 concentrations obtained from the automatic ambient air quality monitoring station were reduced by 75.8, 55.9, 21.4, and 60.7%, respectively, compared with historical data. Besides, the concentration of PM2.5 at sampling sites declined by 41.8% during the partial lockdown. Furthermore, there was a drastic negative relationship between the boundary layer height (BLH) and the daily mean PM2.5 in Hanoi. The concentrations of Cd, Se, As, Sr, Ba, Cu, Mn, Pb, K, Zn, Ca, Al, and Mg during the partial lockdown were lower than those before the partial lockdown. The results of enrichment factor (EF) values and principal component analysis (PCA) concluded that trace elements in PM2.5 before the partial lockdown were more affected by industrial activities than those during the partial lockdown.
Environmental Science and Pollution Research - Using post-mining areas for planting energy crops has emerged as a promising and sustainable reclamation solution due to its potential contributions... 相似文献
In order to find the causative agent in frequently occuring fish kills in a Belgian river a series of toxicity tests has been conducted in which rudd (Scardinius erythrophtalmus) were exposed to acute lethal and subacute non lethal concentrations of copper, chromium, cadmium and zinc. The concentrations of these metals in gills, opercle, kidney, liver and muscle were measured. Metal levels in gills were the most valuable indicator of acute lethal exposure. This information was compared with levels found in rudd from a surface water storage reservoir and from the river Meuse. Fish collected after fish kills in the river Meuse were analysed. In one case copper could be identified as one of the toxicants concerned by fish tissue analysis. Metal levels in fish tissues can give valuable additional information concerning the cause of kills provided that background information is available about metal levels in water and normal tissue levels. 相似文献
A new regenerative wet scrubbing process for flue gas desulphurization, Ispra Mark 13A, is presented. The process produces two useful products, concentrated sulphuric acid and hydrogen. Process flow schemes and process principles are discussed. 相似文献
Bien Hoa airbase is located in Dong Nai Province (Southern Vietnam). Several sites within the airbase are highly contaminated by Agent Orange/Dioxin, and thus, they are also commonly named as an Agent Orange/Dioxin hotpot. In the present study, 36 maternal milk samples were collected from primiparas who have lived at least 5 years in four wards, Buu Long, Quang Vinh, Trung Dung and Tan Phong, which are closed to Bien Hoa airbase in order to investigate the level and distribution of Agent Orange/Dioxin exposure in different local communities. The mean concentrations of PCDD/PCDFs in four investigated wards range from 6.4 to 13.6 pgTEQ/g lipid. The highest mean TEQ of PCDD/PCDFs was observed in Buu Long ward (13.6 pgTEQ/g lipid), followed by Tan Phong ward (12.3 pgTEQ/g lipid), and the lowest value was observed in Trung Dung ward (6.4 pgTEQ/g lipid). The mean concentration of 2,3,7,8-TCDD in Buu Long (7.6 pg/g lipid) was approximately 2–6 times higher than those in Tan Phong (3.9 pg/g lipid), Quang Vinh (2.3 pg/g lipid), or Trung Dung (1.2 pg/g lipid). These results imply site-specific exposure to PCDD/PCDFs in different local communities living around Bien Hoa airbase. The mean values of daily intake of dioxin estimated for the breast fed infants living in Buu Long, Quang Vinh, Trung Dung and Tan Phong were about 80, 37.5, 31.7 and 58 pg TEQ/kg bw/day, respectively. 相似文献
Quantitative risk analysis is in principle an ideal method to map one’s risks, but it has limitations due to the complexity of models, scarcity of data, remaining uncertainties, and above all because effort, cost, and time requirements are heavy. Also, software is not cheap, the calculations are not quite transparent, and the flexibility to look at various scenarios and at preventive and protective options is limited. So, the method is considered as a last resort for determination of risks. Simpler methods such as LOPA that focus on a particular scenario and assessment of protection for a defined initiating event are more popular. LOPA may however not cover the whole range of credible scenarios, and calamitous surprises may emerge.In the past few decades, Artificial Intelligence university groups, such as the Decision Systems Laboratory of the University of Pittsburgh, have developed Bayesian approaches to support decision making in situations where one has to weigh gains and costs versus risks. This paper will describe details of such an approach and will provide some examples of both discrete random variables, such as the probability values in a LOPA, and continuous distributions, which can better reflect the uncertainty in data. 相似文献
Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC50 value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC50 = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM.Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. 相似文献