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1.
Observed changes in average global temperatures over time have led to two general avenues of discussion in the environmental literature. The scientific community has concentrated on the statistical detection of global warming and the determination of biological and industrial factors causing average world temperatures to rise. A second avenue of thought considers the issue of economic abatement by attempting to measure the pecuniary costs of global warming and the elimination of factors influencing this problem. This paper concentrates not on developing an economic model of global warming and environmental damage, but rather on examining the problem from a purely statistical vantage point. Utilising annual data from 1950 to 1991 and optimally determined vector auto regression specifications, it is shown that general industrial growth and greenhouse gas emission levels statistically cause a persistent increase in average global temperatures. In addition, this analysis shows that increasing average world temperatures have a statistically significant negative causal impact on agricultural productivity. Given that global warming is a long-term process culminating from decades of industrial activity, statistically significant causal results derived in this paper using short term data are interesting. Statistical results suggest that trends in average temperatures respond to short-run fluctuations in industrial activity and population growth.  相似文献   

2.
The techniques of Principal Component Analysis (PCA) and subsequent regression analysis were used in an attempt to describe local and upwind chemical and physical factors which affect the variability of SO4 –2 concentrations observed in a rural area of the northeastern U.S. The data used in the analyses included upwind and local O3 concentrations, temperature, relative humidity and other climatological information, SO2, and meteorological information associated with backward trajectories. The investigation identified five principal components, three major (eigenvalues >1) and two minor (eigenvalues < one), which accounted for 52% (r = 0.72) of the variability in the SO4 –2 regression model. These components can be described as representing local and upwind photochemistry, droplet growth, SO2 emissions, and air mass characteristics. The study also indicated that in future studies it will be necessary to a priori select air pollution and meteorological variables for measurement to potentially increase the sensitivity of this type of receptor model.  相似文献   

3.
According to directive 93/67/EEC of the European Commission, this paper deals with the generic exposition evaluation of the environmental concentration of cooling Lubricant chemicals from the metal working industry into the hydrosphere. After considering the relevant life-cycle steps and the selection of a representative point source for the 'reasonable worst case', the emission per day Elocal(water) is determined. It leads to the predicted environmental concentration (PEClocal(water)) for the local stage in the compartment water. In order to gain the PEClocal(water) for an example--a corrosion inhibitor as additive in a cooling lubricant--, the relevant emission paths and the corresponding representative point source are described for the reasonable worst case. For non-water-miscible cooling lubricants, none of the operations in the life cycle leads to a release into the compartment water. To evaluate the hazard potential for cooling lubricant chemicals, the complete risk assessment has to be done. Also, the assessment has to be done for all high production volume chemicals, new substances and existing hazard chemicals. This means that even industrial categories like chemicals used in the textile industry or biocides and others have to be evaluated.  相似文献   

4.
Pilson ME 《Ambio》2006,35(3):130-133
The title sentence was not written by Svante Arrhenius. Furthermore, the context within which he was working would not have led naturally to the creation of such a sentence. The sentence was the work of four separate individuals. Lotka introduced the word "evaporating" in a paragraph where he was discussing Arrhenius views as presented in 1908. Ausubel copied a sentence from Lotka, still with only the word "evaporating" in quotation marks, but without a qualifying phrase, in a paragraph where he was discussing Arrhenius contributions, probably believing that the word was from Arrhenius. Revelle included the whole fragment of a sentence from Ausubel (probably believing that this fragment was from Arrhenius), along with nine direct quotations from Arrhenius (1908), while not saying exactly where they came from. Weiner added the first two words and ascribed the whole sentence to Arrhenius (1896). Subsequent authors have sequentially quoted each other, generally without attribution.  相似文献   

5.
Nitrous acid was the only soluble species initially formed when the effluent of electrical discharges in air was passed through distilled water. The nitrous acid was about 5 % of the total amount of NOx (NO + NO2) produced by these electrical discharges.  相似文献   

6.
Two compounds, 2,4-dinitroanisole (DNAN) and 3-nitro-1,2,4-triazol-5-one (NTO) are the main ingredients in a suite of explosive formulations that are being, or soon will be, fielded at military training ranges. We aim to understand the dissolution characteristics of DNAN and NTO and three insensitive muntions (IM) formulations that contain them. This information is needed to accurately predict the environmental fate of IM constituents, some of which may be toxic to people and the environment. We used Raman spectroscopy to identify the different constituents in the IM formulations and micro computed tomography to image their three-dimensional structure. These are the first three-dimensional images of detonated explosive particles.  相似文献   

7.
大量的原油挥发气一直都被排放到大气中 ,既浪费了能源 ,也污染了环境。本文在分析了排空的巨大危害之后 ,对回收方法进行了探讨 ,提出了利用匹配式多级喷射器进行回收的有效方法。  相似文献   

8.
Photolysis may be a significant route of pesticide dissipation on crops, leading to an increase of pesticide use. Spraying strong absorbing compounds (photoprotector) along with pesticide is an attractive strategy to prevent the photodegradation phenomenon. The aim of this study is to get a better understanding of the parameters governing the photoprotection efficiency. Experiments were conducted using formulated sulcotrione as a pesticide and a grape wine extract as a photoprotector. These compounds were irradiated using simulated solar light as dried deposits on carnauba wax films or on disks of tobacco leaves and analyzed by ultra performance liquid chromatography ultraviolet (UV), spectroscopy, and microscopy. It is shown that photolysis is faster on leaves than on carnauba wax and that the photoprotection effect of grape wine extract is more efficient on leaves than on wax. Images recorded by microscopy bring evidence that deposits are very different on the two supports both in the absence and in the presence of the photoprotector. The grape wine extract plays a double role; it is antioxidant and UV screen. Photoprotection by the grape wine extract is a complex mixing of UV screen and antioxidant effects. The UV screen effect can be rationalized by considering the rate of light absorption by sulcotrione. Our results demonstrate that the rates of sulcotrione phototransformation are mainly governed by the repartition of the deposit on the solid support.  相似文献   

9.
Whiteman G  Forbes BC  Niemelä J  Chapin FS 《Ambio》2004,33(6):371-376
This paper discusses the role of companies in high-latitude regions, which are conceptualized as socially and economically mediated ecosystems, and identifies a number of important social actors within the business environment. We present three examples of corporate activity at high latitudes and discuss a variety of common threads. Notably, we argue that business theory and practice needs to move beyond a narrow social or economic concept of organizational resilience and embrace the ecological resilience of high-latitude regions as a business management goal. We also suggest that regional ecosystem resilience needs to become a meaningful measure of sustainable corporate governance, one that corporate boards of directors can review and commit to. The paper concludes with a call for a detailed research agenda on the role of transnational and national companies within high-latitude regions.  相似文献   

10.
Legler J 《Chemosphere》2008,73(2):216-222
The objective of this review is to provide an overview of recent studies demonstrating the endocrine disrupting (ED) effects of brominated flame retardants (BFRs), while highlighting interesting data presented at the recent international BFR workshop in Amsterdam in April, 2007. A review written in 2002 was used as a starting point and about 60 publications published since 2003 were reviewed. New insights into the in vivo effects of BFRs on thyroid hormone, estrogen and androgen pathways in both mammalian and non-mammalian models are provided, and novel (in vitro) findings on the mechanisms underlying ED effects are highlighted. Special attention is also given to reports on neurotoxicological effects at relatively low doses of BFRs, although an endocrine-related mechanism is disputable. Convincing evidence has been published showing that BFRs and importantly, BFR metabolites, have the potential to disrupt endocrine systems at multiple target sites. While some studies suggest a wide margin of safety between effect concentrations in rodent models and levels encountered in humans and the environment, other studies demonstrate that exposure to low doses relevant for humans and wildlife at critical time points in development can result in profound effects on both endocrine pathways and (neuro)development.  相似文献   

11.
Effectiveness and mechanism of cadmium (Cd) sorption on original, acidified and ball milling nano-particle red muds were investigated using batch sorption experiments, sequential extraction analysis and X-ray absorption near edge structure (XANES) spectroscopy. The maximum sorption capacity of Cd was 0.16, 0.19, and 0.21 mol/kg for the original, acidified, and nano-particle red muds at pH 6.5, respectively. Both acidification and ball-milling treatments significantly enhanced Cd sorption and facilitated transformation of Cd into less extractable fractions. The Cd LIII-edge XANES analysis indicated the formation of inner-sphere complexes of Cd similar to XCdOH (X represents surface groups on red mud) on the red mud surfaces although outer-sphere complexes of Cd were the primary species. This work shed light on the potential application of red mud to remediate Cd-contaminated soils and illustrated the promising tool of XANES spectroscopy for speciation of multicomponent systems of environmental relevance.  相似文献   

12.
Environmental Science and Pollution Research - No effective strategy has been found so far to control the emission of microplastics. The purpose of this article is to review the available control...  相似文献   

13.
上海一直致力于探索符合特大型城市特点的可持续发展道路,努力建设资源节约型环境友好型城市.2010年,世博会的召开对上海的环境保护工作既是机遇也是挑战.  相似文献   

14.
Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The “glucosamine” and “reducing sugar” parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium.  相似文献   

15.
Use of fungi for the bioconversion of rice straw into cellulase enzyme   总被引:1,自引:0,他引:1  
Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The "glucosamine" and "reducing sugar" parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium.  相似文献   

16.
The use of high resolution (10,000 resolving power) coupled gas chromatography - mass spectrometry is a well established technique in the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) but in the case of heavily contaminated stack samples interferences can still occur. A complementary technique that offers high specificity is selected reaction monitoring (SRM).A study has been made into the effects that affect the metastable dissociation of 2,3,7,8-TCDD in the first field free region (FFR1) of a magnetic sector mass spectrometer, and monitored using SRM.Monatomic, diatomic and polyatomic gases have been investigated in the collision chamber of the mass spectrometer, as have the effects of electron energy, source temperature and trap current on the dissociation, and optima conditions determined for them.  相似文献   

17.
We present direct evidence of the release of synthetic nanoparticles from urban applications into the aquatic environment. We investigated TiO2 particles as these particles are used in large quantities in exterior paints as whitening pigments and are to some extent also present in the nano-size range.TiO2 particles were traced from exterior facade paints to the discharge into surface waters. We used a centrifugation based sample preparation which recovers TiO2 particles between roughly 20 and 300 nm. Analytical electron microscopy revealed that TiO2 particles are detached from new and aged facade paints by natural weather conditions and are then transported by facade runoff and are discharged into natural, receiving waters. Microscopic investigations are confirmed by bulk chemical analysis. By combining results from microscopic investigations with bulk chemical analysis we calculated the number densities of synthetic TiO2 particles in the runoff.  相似文献   

18.
19.
Thomas-Walters  Laura  McNulty  Claire  Veríssimo  Diogo 《Ambio》2020,49(6):1135-1145

With the recognition that most global environmental problems are a result of human actions, there is an increasing interest in approaches which have the potential to influence human behaviour. Images have a powerful role in shaping persuasive messages, yet research on the impacts of visual representations of nature is a neglected area in biodiversity conservation. We systematically screened existing studies on the use of animal imagery in conservation, identifying 37 articles. Although there is clear evidence that images of animals can have positive effects on people’s attitudes to animals, overall there is currently a dearth of accessible and comparable published data demonstrating the efficacy of animal imagery. Most existing studies are place and context-specific, limiting the generalisable conclusions that can be drawn. Transdisciplinary research is needed to develop a robust understanding of the contextual and cultural factors that affect how animal images can be used effectively for conservation purposes.

  相似文献   

20.
Our main objective was to isolate bacteria from soil contaminated with effluents from electroplating wastewater and assess their potential to remove copper from the aqueous phase. The strain identified as Bacillus polymyxa accumulated copper inside the cell, where it bound to the cell wall. The intracellular metal accumulation led to the inhibition of dehydrogenases, which is essential for the energy deriving reactions. Addition of thiol group containing compounds, like reduced glutathione, dithiothreitol and mercapto-ethanol, revived the enzyme activity, implicating the sulfhydryl groups as the target of metal action. However, when the cells were exposed to higher concentration of Cu(II), irreversible enzyme denaturation occurred. Desorption with DTT and citrate showed that 82% of the metal was accumulated on cell surface and the contribution from metabolism-dependent intracellular accumulation was only 10-12%. The surface characterization of B. polymyxa indicated the presence of carboxyl, imidazolium, amino and phenolic groups, which might be responsible for metal uptake. Electron paramagnetic resonance (EPR) spectroscopy studies indicated that the metal coordinating environment could be either CuN2O2 or CuNO3 chromophores, which may be the result of binding of Cu(II) to oxygen atoms of carboxylic groups of cell wall peptidoglycan and nitrogen atoms of amino-sugars or structural proteins. This environment got slightly altered after several treatments of B. polymyxa, leading to the formation of CuO4, suggesting the coordination of copper to four oxygen atoms derived from carboxyl groups of peptidoglycan.  相似文献   

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