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A complete record of annual methyl chloroform production has been compiled by combining early estimates in the technical literature (1951–1976) with audited production data supplied by chemical manufacturers (1970–1996) and with production and consumption estimates provided by the countries party to the Montreal Protocol (1989 to the present). From this, a new and comprehensive estimate of annual emissions has been developed. However, when the atmospheric concentrations calculated from these annual emissions are compared with measured concentrations, there are significant discrepancies, particularly during recent years, that merit further examination.  相似文献   

3.
Environmental Science and Pollution Research - Anaerobic ammonium oxidation (anammox) is one of the most promising processes for the treatment of ammonium-rich wastewater. It is more effective,...  相似文献   

4.
Environmental Science and Pollution Research - The Chinese government has given a high priority to economic high-quality development (HQD) in recent years. This study empirically examines whether...  相似文献   

5.
Exposure efficiency: an idea whose time has come?   总被引:1,自引:0,他引:1  
Evans JS  Wolff SK  Phonboon K  Levy JI  Smith KR 《Chemosphere》2002,49(9):1075-1091
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6.

In sustainable development, energy is critical in human activities and shapes a sustainable future. Thus, it is an unignorable element in human development. This paper analyzes the contributions of renewable energy sources (RES)’s to the economic, environmental, and social dimensions of sustainable development. Moreover, we add energy security as a possible fourth dimension into the analysis. For the sample size, we limit the countries members of the OECD and run generalized methods of moments for the period from 1995 to 2015. This method can produce efficient estimators under the problems of endogeneity, omitted-variable bias, measurement errors, and heteroscedastic residuals. According to the results, RES has a small reducing effect (?.007%) on output in the Cobb-Douglas production function for the economic dimension. We found that RES has a positive contribution to the environmental dimension and abates the level of carbon emission (?.093%). RES also confirms the inverted-U shape of environmental Kuznets curve. In the social dimension, RES improves human development and a 1% increase in RES consumption causes to .0045% increase in human development. In the last contribution, RES has a positive effect on sustainable energy supply security in the context of electricity generation (.032%). Although the effects of RES on the environment, social, and energy security are significant, they are limited. These limitations point to barriers that can be overcome over time. Our conclusions recommend that these effects might flourish with technical developments and political support in the long run. Furthermore, public awareness, rising income level, and economies of scale are also beneficial in this process. As a result, RES might be an excellent source for a sustainable future and development. Especially, RES might have remarkable contributions to the 7th, 11th, 12th, and 13th goals of sustainable development.

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7.
Environmental Science and Pollution Research - Tetracycline hydrochloride (TCH) electro-oxidation by commercial DSA® and commercial DSA® modified by platinum electrodeposition was...  相似文献   

8.
The interactions of cetyltrimethylammonium (CTA) with mitochondria have been investigated. We confirm, as already observed in a previous paper, that this compound behaves as proton carrier (or uncoupler) of the oxidative phosphorylation, but evidences suggest that this compound enhances the membrane permeability to many other compounds such as sucrose. We conclude therefore that CTA as a detergent enhances membrane permeability to all ions including protons. Some evidences are also given that the inhibitory effect of CTA on the mitochondrial respiratory chain is a consequence of the swelling induced.  相似文献   

9.
- Triggered by the detection of a large variety of pharmaceuticals in surface waters, soils and groundwaters across the world (e.g. Halling- Sørensen et al. 1998, Daughton & Ternes 1999, Jones et al. 2001, Heberer 2002) and the widespread occurrence of endocrine active compounds and related effects in the environment (e.g. Purdom et al. 1994, Tyler et al. 1998, Vethaak et al. 2002), pharmaceuticals in the environment have become an issue for both the scientific and the public community. During the last few years, our understanding of the fate and effects of pharmaceuticals in the environment has progressed significantly. However, there are still a number of uncertainties concerning the effects of pharmaceuticals on the environment and the assessment of potential exposure (e.g. Hanisch et al. 2004, Salomon 2005). These uncertainties will be addressed by the EU-project ‘Environmental risk assessment of pharmaceuticals’ (ERAPharm). This project, a specific targeted research project, is carried out within the priority ‘Global change and ecosystems’ of the 6th framework programme of the European Union. ERAPharm has started on 1st October 2004; the project duration is three years.  相似文献   

10.
Environmental Science and Pollution Research - The determination of trace-level pharmaceuticals in water is generally performed using liquid chromatography combined with mass spectrometry, which is...  相似文献   

11.
The treatment efficiency, as toxicity removal, of complex effluents from the Industrial District of Cama?ari (BA, Brazil), after biological treatment with activated sludge was evaluated using Microtox. Samples of the equalised effluent (EE) were collected prior to treatment together with samples of the treated effluent (TE), which remained 24 h in the treatment plant. Rehydrated colonies of Vibrio fischeri were exposed to sequential dilutions of EE and TE to assess luminosity interference. Values for EC50 were calculated, together with the respective toxicity units. In all, twenty assays of each effluent type were carried out and the mean toxicity removal was 92.71%, while the chemical oxygen demand (COD) presented mean reduction of 83.04%. There was a variability of an order of magnitude between the Microtox results for the two types of effluents. The mean EC50 values were 2.12 for EE and 47.78% for TE. In spite of its weakness in some conditions, the Microtox system demonstrated to work adequately in assessing effluent toxicity removal in this treatment plant and therefore can be used for further toxicity removal programs.  相似文献   

12.
Decamethyl cyclopentasiloxane (D5) and decamethyl tetrasiloxane (MD2M) were injected into a smog chamber containing fine Arizona road dust particles (95% surface area <2.6 μM) and an urban smog atmosphere in the daytime. A photochemical reaction – gas–particle partitioning reaction scheme, was implemented to simulate the formation and gas–particle partitioning of hydroxyl oxidation products of D5 and MD2M. This scheme incorporated the reactions of D5 and MD2M into an existing urban smog chemical mechanism carbon bond IV and partitioned the products between gas and particle phase by treating gas–particle partitioning as a kinetic process and specifying an uptake and off-gassing rate. A photochemical model PKSS was used to simulate this set of reactions. A Langmuirian partitioning model was used to convert the measured and estimated mass-based partitioning coefficients (KP) to a molar or volume-based form. The model simulations indicated that >99% of all product silanol formed in the gas-phase partition immediately to particle phase and the experimental data agreed with model predictions. One product, D4TOH was observed and confirmed for the D5 reaction and this system was modeled successfully. Experimental data was inadequate for MD2M reaction products and it is likely that more than one product formed. The model set up a framework into which more reaction and partitioning steps can be easily added.  相似文献   

13.
Environmental Science and Pollution Research - The massive use of pesticides brings considerable environmental and human health impacts. This study conducted an overall assessment of the ecological...  相似文献   

14.
Environmental Science and Pollution Research - The North Bohemian Brown Coal Basin (Czech Republic) is suggested as a source of significant pollution in the surrounding environment with various...  相似文献   

15.
This paper compares the cost-effectiveness of life-saving interventions in Japan, based on information collected from the health, safety and environmental literature. More than 50 life-saving interventions are analyzed. Cost-effectiveness is defined as the cost per life-year saved or as the cost per quality-adjusted life-year saved. Finding a large cost-effectiveness disparity between chemical controls and health care intervention, we raise the question of whether chemical regulations cost society too much. We point out the limitations of this study and propose a way to improve the incorporation of morbidity effects in cost-effectiveness analysis.  相似文献   

16.
The results of the inorganic and organic analyses of aerosol samples collected on the east and west sides of Hong Kong during a dust episode (9–10 May 1996) are reported. The origin of the dust was traced to Northern China. The dust reached Hong Kong by way of the East China Sea. The characteristics of the inorganic elements and organic compounds were quite different from the non-episodic samples collected on 1–2 April 1996, EPD (Environmental Protection Department, Special Administrative Region, Hong Kong, China) results for April–May 1994, and our early studies (Zheng et al., 1997. Atmospheric Environment 31(2), 227–237.). Results from X-ray spectrometry showed pronounced increase in the relative abundance of Al, Fe, Ca, S and Cl in the dust samples compared to the non-episodic samples. The high abundance of Cl in the dust samples suggested the aerosols experienced long-range transport by way of the sea. ICP-MS analysis revealed higher concentrations of Fe, Ca, S and Pb in the episodic samples relative to the values measured during April–May 1994 by EPD. The high Ca content in the soil samples is a characteristic of northern Chinese crustal material (Liu et al., 1985). Hong Kong aerosols are characterized by high octadecenoic acid concentration due to heavy urbanization and Chinese-style stir-fry cooking. A much lower C18:1/C18:0 ratio was found in the episodic samples, however, suggesting the aerosols were transported from a long distance. The high ratio of ⩾C20/<C20 in n-alkanoic acids, the high input of n-alkanes and n-alkanols from plant waxes, and the unusually similar distribution of the organic compounds in the east and west samples suggested the existence of non-local sources on 9–10 May 1996. The compositions and distributions of lipids in the aerosol samples collected during the episode corresponded well with those of the eolian dust samples over the Atlantic and Pacific Oceans. Back trajectories and low altitude (<3 km) mesoscale flow modeling were performed, suggesting the existence of a mesoscale atmospheric structure off the east China coast, which could be responsible for the dust episode. Surface charts indicated the presence of suspended dust near Shanghai on 8 May 1996. Taiwan also experienced a similar episode on 8–9 May 1996. This integrated, multi-technique approach provides clear evidence that the 9–10 May episode was attributed to a consequence of Asian Dust. This is the first scientific report of Asian Dust in Hong Kong.  相似文献   

17.
Environmental Science and Pollution Research - It is essential to study CO2 emissions intensity as the most critical factor affecting temperature increase and climate change in a country like Iran,...  相似文献   

18.
An investigation of the effect of relative humidity on aerosol formation from m-xylene and 1,3,5-trimethylbenzene photooxidation is reported. Experiments were performed in the presence and absence of ammonium sulfate seed particles (both aqueous and dry) to ascertain the effect of partitioning of oxidation products into a strong electrolytic solution or onto dry crystalline seed particles. In marked contrast to the α-pinene/ozone system, the final measured secondary organic aerosol yield was unaffected by the presence of gas-phase or liquid-phase water at relative humidities (RH) up to 50%. The hygroscopic nature of the aerosol generated upon photooxidation of m-xylene and 1,3,5-trimethylbenzene was examined; the hygroscopicity of the aerosol at 85% RH for both parent organics increased with the extent of the reaction, indicating that the first-generation oxidation products undergo further oxidation. Limited identification of the gas- and aerosol-phase products of m-xylene and 1,3,5-trimethylbenzene photooxidation is reported. It is evident that a more complete molecular identification of aromatic photooxidation aerosol awaits analytical techniques not yet brought to bear on this problem.  相似文献   

19.
The effect of relative humidity (RH) on aerosol formation by the semi-volatile oxidation products of the α-pinene/O3 system has been comprehensively studied. Experiments were performed in the presence of ammonium sulfate (aqueous, dry), ammonium bisulfate seed (aqueous, dry), and aqueous calcium chloride seed aerosols to ascertain their effect on the partitioning of the oxidation products. The yield of organic aerosol varies little with RH, and is not affected by the presence of dry inorganic salt aerosols. Aqueous salt aerosols reduce the yield of organic aerosol compared to that under seed-free or dry seed conditions. The degree of reduction is electrolyte dependent, with aqueous ammonium sulfate leading to the largest reduction and aqueous calcium chloride the smallest. Hygroscopic growth of the organic aerosol from <2% to 85% RH was also monitored, and could be satisfactorily represented as the sum of the individual contributions of the organic and inorganic fractions. The implications of the growth factor measurements for concentration/activity relationships of the condensed phase organic material (assuming a liquid solution) was explored. The formation of the organic aerosol was investigated using a simple two component model, and also one including the 12 product compounds identified in a previous study. The experimental results for <2% and 50% RH (without salt seed aerosols) could be satisfactorily predicted. However, the aqueous salt seed aerosols are predicted to increase the overall yield due to the dissolution of the organic compounds into the water associated with the seed aerosol—the opposite effect to that observed. The implications of two distinct phases existing the aerosol phase were investigated.  相似文献   

20.
The cycle of mercury (Hg) from a gigantic landfill area (area ∼2.72 km2) was investigated by conducting micrometeorological measurements of its exchange rates across soil–air boundary during the spring season of 2000. Based on this field campaign, we attempted to provide various insights into the Hg exchange processes, especially with respect to the decoupling of the mixed signatures of complex source processes. According to our analysis, the cycle of Hg in the study site appeared to be affected significantly by the vent processes; excessive amount of Hg was expected to be released via ventpipes penetrating up to 60 m depths of the deep landfilled waste layer. The influence of these vent source processes was reflected very sensitively by the windrose pattern. The data collected during the non-easterly winds were representing the typical pattern for a strong source area in which upward emission is predominant in both strength and frequency. On the other hand, the data collected from the easterly winds were characterized by excessive deposition of Hg which we suspect is due mostly to the nearest vent located easterly from our measurement spot. The unique characteristics of each data group, divided by windrose pattern, were consistent from apparent difference in: (1) the absolute magnitude of gradient/flux data sets, (2) frequency of exchange for each of two vertical directions, and (3) E/D (emission/deposition) ratios for most relevant parameters. The analysis of the short-term variability of exchange patterns over a 24-h scale, also exhibited that the patterns for two different conditions were quite contrasting as a function of time. The magnitude of bidirectional fluxes in the present study is significantly high with values of 254±224 (N=71 emissions out of 79 fluxes quantified during non-easterly winds) and −1164±1276 ng m−2 h−1 (N=14 depositions out of 16 fluxes during easterly winds), respectively. If the computed emission rate is extrapolated, we estimate that annual emission of Hg from the study area can amount to approximately 6 kg which is comparable with the estimates for other areas around the globe under strong Hg-pollution.  相似文献   

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