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1.
Application of appropriate environmentally conscious manufacturing strategies enables the sustainable development of products and processes. Automotive component manufacturers recognise the potential of applying appropriate strategies for attaining Triple Bottom Line benefits. In this context, three strategies such as eco-efficiency, waste minimisation and material efficiency are being applied to minimise environmental impacts associated with the manufacture of automotive products and its associated processes. A case study of an automotive component manufacturing firm has been exemplified. After conducting the study, the potential environmental impact was reduced by 20% and eco-efficiency was improved by 13%. Further, improvements have been observed in terms of overall resource consumption and material efficiency. The overall power consumption was reduced by 18% and weight of the component was reduced by 11%. The study aimed at improving the sustainable performance of product by incorporating green and environmentally friendlier manufacturing practices.

Abbreviations: USEPA: United Nations Environmental Protection Agency; OECD: Organisation for Economic Co-operation and Development; WBCSD: World Business Council for Sustainable Development; Eco-QFD: Environmental Quality Function Deployment; WCED: World Commission on Environment and Development; LCA: Life Cycle Assessment  相似文献   

2.
Community-based collaborative groups involved in public natural resource management are assuming greater roles in planning, project implementation, and monitoring. This entails the capacity of collaborative groups to develop and sustain new organizational structures, processes, and strategies, yet there is a lack of understanding what constitutes collaborative capacity. In this paper, we present a framework for assessing collaborative capacities associated with community-based public forest management in the US. The framework is inductively derived from case study research and observations of 30 federal forest-related collaborative efforts. Categories were cross-referenced with literature on collaboration across a variety of contexts. The framework focuses on six arenas of collaborative action: (1) organizing, (2) learning, (3) deciding, (4) acting, (5) evaluating, and (6) legitimizing. Within each arena are capacities expressed through three levels of social agency: individuals, the collaborative group itself, and participating or external organizations. The framework provides a language and set of organizing principles for understanding and assessing collaborative capacity in the context of community-based public forest management. The framework allows groups to assess what capacities they already have and what more is needed. It also provides a way for organizations supporting collaboratives to target investments in building and sustaining their collaborative capacities. The framework can be used by researchers as a set of independent variables against which to measure collaborative outcomes across a large population of collaborative efforts.  相似文献   
3.
ABSTRACT

The aim of this paper is to show that a photochemical box model could describe the air pollution diurnal profiles within a typical street canyon in the city of Athens. As sophisticated three-dimensional dispersion models are computationally expensive and they cannot serve to simulate pollution levels in the scale of an urban street canyon, a suitably modified three-layer photochemical box model was applied. A street canyon of Athens with heavy traffic was chosen to apply the aforementioned model. The model was used to calculate pollutant concentrations during two days with meteorological conditions favoring pollutant accumulation. Road traffic emissions were calculated based on existing traffic load measurements. Meteorological data, as well as various pollutant concentrations, in order to compare with the model results, were provided by available measurements. The calculated concentrations were found to be in good agreement with measured concentration levels and show that, when traffic load and traffic composition data are available, this model can be used to predict pollution episodes. It is noteworthy that high concentrations persisted, even after additional traffic restriction measures were taken on the second day because of the high pollution levels.  相似文献   
4.
In this study, the efficiency of six ion exchange resins to reduce the dissolved organic matter (DOM) from a biologically treated newsprint mill effluent was evaluated and the dominant removal mechanism of residual organics was established using advanced organic characterisations techniques. Among the resins screened, TAN1 possessed favourable Freundlich parameters, high resin capacity and solute affinity, closely followed by Marathon MSA and Marathon WBA. The removal efficiency of colour and lignin residuals was generally good for the anion exchange resins, greater than 50% and 75% respectively. In terms of the DOM fractions removal measured through liquid chromatography–organic carbon and nitrogen detector (LC–OCND), the resins mainly targeted the removal of humic and fulvic acids of molecular weight ranging between 500 and 1000 g mol?1, the portion expected to contribute the most to the aromaticity of the effluent. For the anion exchange resins, physical adsorption operated along with ion exchange mechanism assisting to remove neutral and transphilic acid fractions of DOM. The column studies confirmed TAN1 being the best of those screened, exhibited the longest mass transfer zone and maximum treatable volume of effluent. The treatable effluent volume with 50% reduction in dissolved organic carbon (DOC) was 4.8 L for TAN1 followed by Marathon MSA – 3.6 L, Marathon 11 – 2.0 L, 21K-XLT – 1.5 L and Marathon WBA – 1.2 L. The cation exchange resin G26 was not effective in DOM removal as the maximum DOC removal obtained was only 27%. The resin capacity could not be completely restored for any of the resins; however, a maximum restoration up to 74% and 93% was achieved for TAN1 and Marathon WBA resins. While this feasibility study indicates the potential option of using ion exchange resins for the reclamation of paper mill effluent, the need for improving the regeneration protocols to restore the resin efficiency is also identified. Similarly, care should be taken while employing LC–OCND for characterising resin-treated effluents, as the resin degradation is expected to contribute some organic carbon moieties misleading the actual performance of resin.  相似文献   
5.
Abstract

Observations of the mass and chemical composition of particles less than 2.5 μm in aerodynamic diameter (PM2.5), light extinction, and meteorology in the urban Baltimore-Washington corridor during July 1999 and July 2000 are presented and analyzed to study summertime haze formation in the mid-Atlantic region. The mass fraction of ammoniated sulfate (SO4 2-) and carbonaceous material in PM2.5 were each ~50% for cleaner air (PM2.5 < 10 μg/m3) but changed to ~60% and ~20%, respectively, for more polluted air (PM2.5 > 30 μg/m3). This signifies the role of SO4 2- in haze formation. Comparisons of data from this study with the Interagency Monitoring of Protected Visual Environments network suggest that SO4 2? is more regional than carbonaceous material and originates in part from upwind source regions. The light extinction coefficient is well correlated to PM2.5 mass plus water associated with inorganic salt, leading to a mass extinction efficiency of 7.6 ± 1.7 m2/g for hydrated aerosol. The most serious haze episode occurring between July 15 and 19, 1999, was characterized by westerly transport and recirculation slowing removal of pollutants. At the peak of this episode, 1-hr PM2.5 concentration reached ~45 μg/m3, visual range dropped to ~5 km, and aerosol water likely contributed to ~40% of the light extinction coefficient.  相似文献   
6.
Positive matrix factorization (PMF) and effective variance (EV) solutions to the chemical mass balance (CMB) were applied to PM2.5 (particulate matter with an aerodynamic diameter <2.5 μm) mass and chemically speciated measurements for samples taken from 2008 to 2010 at the Atlanta, Georgia, and Birmingham, Alabama, sites. Commonly measured PM2.5 mass, elemental, ionic, and thermal carbon fraction concentrations were supplemented with detailed nonpolar organic speciation by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). Source contribution estimates were calculated for motor vehicle exhaust, biomass burning, cooking, coal-fired power plants, road dust, vegetative detritus, and secondary sulfates and nitrates for Atlanta. Similar sources were found for Birmingham, with the addition of an industrial source and the separation of biomass burning into open burning and residential wood combustion. EV-CMB results based on conventional species were qualitatively similar to those estimated by PMF-CMB. Secondary ammonium sulfate was the largest contributor, accounting for 27–38% of PM2.5, followed by biomass burning (21–24%) and motor vehicle exhaust (9–24%) at both sites, with 4–6% of PM2.5 attributed to coal-fired power plants by EV-CMB. Including organic compounds in the EV-CMB reduced the motor vehicle exhaust and biomass burning contributions at both sites, with a 13–23% deficit for PM2.5 mass. The PMF-CMB solution showed mixing of sources within the derived factors, both with and without the addition of speciated organics, as is often the case with complex source mixtures such as those at these urban-scale sites. The nonpolar TD-GC/MS compounds can be obtained from existing filter samples and are a useful complement to the elements, ions, and carbon fractions. However, they should be supplemented with other methods, such as TD-GC/MS on derivitized samples, to obtain a wider range of polar compounds such as sterols, sugars, and organic acids. The PMF and EV solutions to the CMB equations are complementary to, rather than replacements for, each other, as comparisons of their results reveal uncertainties that are not otherwise evident.

Implications:?Organic markers can be measured on currently acquired PM2.5 filter samples by thermal methods. These markers can complement element, ion, and carbon fraction measurements from long-term speciation networks. Applying the positive matrix factorization and effective variance solutions for the chemical mass balance equations provides useful information on the accuracy of the source contribution estimates. Nonpolar compounds need to be complemented with polar compounds to better apportion cooking and secondary organic aerosol contributors.  相似文献   
7.
The safety of Tinospora cordifolia and its potential to protect against ultraviolet radiation‐induced cytotoxicity and DNA damage in PC12 cells were investigated. To evaluate the safety of T. cordifolia, cell viability and agarose gel electrophoresis were carried out using PC12 cells treated with 0 to 100 μg mL?1 of methanol extract of T. cordifolia. T. cordifolia extracts did not show cytotoxicity ranging 0 to 100 μg mL?1. In addition, T. cordifolia extracts significantly increased cell viability at 1 ng, 10 ng and 1 μg mL?1 concentrations in serum‐deprived medium compared to control. To confirm the protective role against UV‐induced damage, PC12 cells alone or in the presence of 10 ng, 100 ng, or 1 μg mL?1 of T. cordifolia extract were exposed to 250, 270 and 290 nm of UV radiation, which corresponded to doses of 120, 150 and 300 mJ cm?2, respectively. Treatment with T. cordifolia extracts significantly increased the cell survival rate irradiated at 290 nm. In addition, T. cordifolia extracts significantly reduced cyclobutane pyrimidine dimer formation induced by UV irradiation at all wavelengths. In conclusion, T. cordifolia is not toxic and safe for cells. Our findings can support its application as phototherapy in the medical sector.  相似文献   
8.
The Minnesota Particulate Matter 2.5 (PM2.5) Source Apportionment Study was undertaken to explore the utility of PM2.5 mass, element, ion, and carbon measurements from long-term speciation networks for pollution source attribution. Ambient monitoring data at eight sites across the state were retrieved from the archives of the Interagency Monitoring of Protected Visual Environments (IMPROVE) and the Speciation Trends Network (STN; part of the Chemical Speciation Network [CSN]) and analyzed by an Effective Variance – Chemical Mass Balance (EV-CMB) receptor model with region-specific geological source profiles developed in this study. PM2.5 was apportioned into contributions of fugitive soil dust, calcium-rich dust, taconite (low grade iron ore) dust, road salt, motor vehicle exhaust, biomass burning, coal-fired utility, and secondary aerosol. Secondary sulfate and nitrate contributed strongly (49–71% of PM2.5) across all sites and was dominant (≥60%) at IMPROVE sites. Vehicle exhausts accounted for 20–70% of the primary PM2.5 contribution, largely exceeding the proportion in the primary PM2.5 emission inventory. The diesel exhaust contribution was separable from the gasoline engine exhaust contribution at the STN sites. Higher detection limits for several marker elements in the STN resulted in non-detectable coal-fired boiler contributions which were detected in the IMPROVE data. Despite the different measured variables, analytical methods, and detection limits, EV-CMB results from a nearby IMPROVE-STN non-urban/urban sites showed similar contributions from regional sources – including fugitive dust and secondary aerosol. Seasonal variations of source contributions were examined and extreme PM2.5 episodes were explained by both local and regional pollution events.  相似文献   
9.

To eradicate the aquatic pollution caused by dyes, trendily the global researchers provide dedication to dye degradation using nanostructured photocatalyst. This research work is dedicated to explore an advanced, facile, bio-compact green fabricated nanostructure for water refinement. In this regard, plant-mediated syntheses of pure CeO2 and Mn-decorated CeO2 nano-powders have been inspected using seed extract of Cassia angustifolia. Investigations through UV-diffuse reflectance spectroscopy explored the significantly tuned band gap of Mn:CeO2. FT-IR spectroscopy shows the existing functional groups of high-potential phenolic compounds, proteins, and amino acids in Cassia angustifolia act as reducing and capping agents involved in the green fabricated nanostructured samples. X-ray diffraction pattern has been exposed to crystalline cubic fluorite morphology in a single phase and it leads to a regulated optimized amount of Mn on CeO2 nanostructure. The FESEM analysis predicts the morphology of CeO2 in spherical and Mn:CeO2 in flower-like structure. The HRTEM analysis has portrayed particle size of CeO2 is 11 nm and tuned Mn:CeO2 nanostructure is 9 nm. The HRTEM images revealed the average particle size in the range 10–12 nm in CeO2 and 8–9 nm in 5 mol% Mn:CeO2 nanoparticles. It showed a decrease in average particle size with an increase in Mn concentration and the reduction in size may be due to the replacement of Ce(IV) with Mn(II) ions. The elemental composition in nanostructure was predicted using energy-dispersive X-ray analysis. The rapid photocatalytic degradation efficiency of malachite green was effectually performed and compared with the kinetics model of Mn:CeO2 and pure CeO2 nanostructures. From the augmented results, tuned Mn:CeO2 was found to act as the finest green fabricated photocatalyst in the amputation of lethal and carcinogenic dye.

  相似文献   
10.

There are concerns that microplastics act as a vector of pharmaceuticals in the aquatic environment. Most studies have focussed on pharmaceutical adsorption and have not investigated desorption in the various matrices that microplastics enter. Therefore we studied the desorption of the antidepressant drug fluoxetine from polyethylene terephthalate (PET) microplastics in river water, sea water, and simulated gastric and intestinal fluids. We found that most desorption occurred rapidly, within a few hours of exposure. Fluoxetine desorption fitted well to the Freundlich isotherm with r2 values ranging from 0.97 to 0.99. Desorption decreased in the following order: gastric fluid at 20 °C and 37 °C; sea water at 20 °C; intestinal fluid at 20 °C and 37 °C; then river water at 20 °C. The little difference in desorption in gastrointestinal fluids at 20 °C and 37 °C suggests a similar exposure risk to cold- and warm-blooded organisms following PET microplastic ingestion. Total desorption following sequential incubation 2 h in gastric fluid then 4 h in intestinal fluid to mimic gastrointestinal digestion was 37% at 20 °C and 41% at 37 °C. Interestingly, higher desorption of 18–23% occurred in sea water compared to river water, of 4–11%. Under a worst-case scenario, more than 44 mg kg−1 body weight d−1 or more than 52 mg kg−1 body weight d−1 of PET microplastics from river water or sea water, respectively, need to be consumed to exceed the mammalian acceptable daily intake for fluoxetine. Further studies are needed on microplastic ingestion and the bioavailability of adsorbed pharmaceuticals to a range of exposed aquatic organisms.

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