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Triacetylcellulose(TAC)-based globular activated carbons having the adsorption capacity comparable with commercial ones have been derived using a carbonization system developed for this purpose. The carbonization of TAC proceeds through a liquid phase causing bubbling due to the emission of the decomposition gases. The phosphorus compounds resulting from the starting material of TAC waste promote the activation reactions to produce micro-pores.  相似文献   
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Samples of precipitation events (snow and rain) in Dalian, a typical coastal town in China, were analyzed for perfluorosulfonates (PFSAs) and perfluorocarboxylates (PFCAs) to investigate atmospheric contamination by these compounds. In the snow event on December 16, 2006, samples were collected from 21 different sites and in another 6 precipitation events, samples were collected from a single location. Four PFSAs (C4, C6, C8, C10) and seven PFCAs (C6–12) were analyzed. Among the homologues, perfluorooctane sulfonate (PFOS) concentrations were the highest with a geometric mean (GM) of 145 ng/L (n = 21) during the snow event on December 16, 2006, followed by perfluorooctanoate (PFOA) with a GM of 24.7 ng/L (n = 21). Concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and perfluoroheptanoate (PFHpA) were more than two orders of magnitude lower than that of PFOS. Other PFSAs and PFCAs were found to be below the limit of detection in all the samples. In other 6 precipitation events, PFSAs and PFCAs were detected approximately in the same order of magnitude in both snow and rain. The results indicate that wet deposition may be a potential transport mechanism of perfluorinated chemicals in the environment.  相似文献   
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The proximity principle—disposing of waste close to its origin—has been a central value in municipal solid waste (MSW) management in Japan for the last 30 years and its widespread adoption has helped resolve numerous “Not in My Backyard” issues related to MSW management. However, MSW management costs have soared, in large part because of aggressive recycling efforts and because most MSW is incinerated in a country that has scarce landfill capacity. In addition, smaller, less sophisticated incinerators have been closed because of high dioxin emissions. Rising costs combined with the closure of smaller incinerators have shifted MSW management policy toward regionalization, which is the sharing of waste management facilities across municipalities. Despite the increased use of regionalized MSW facilities, the proximity principle remains the central value in Japanese MSW management. Municipal solid waste management has become increasingly regionalized in the United States, too, but different driving forces are at work in these two countries. The transition to regionalized MSW management in Japan results from strong governmental control at all levels, with the central government providing funds and policy direction and prefectures and municipalities being the primary implementing authorities. By contrast, market forces are a much stronger force with US MSW management, where local governments—with state government oversight—have primary responsibility for MSW management. We describe recent changes in Japan’s MSW programs. We examine the connections between MSW facility regionalization, on the one hand, and, on the other hand, the proximity principle, coordination among local governments, central government control, and financing mechanisms.  相似文献   
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The objective of this study was to investigate the reproductive success (fertility and fecundity) of medaka (Oryzias latipes) exposed to 4-nonylphenol (4-NP) in water and the viability of their F(1) offspring. In addition, we measured the bioconcentration of 4-NP in eggs. After a 21-d exposure to 100microg/l 4-NP, medaka showed reduced egg production and fertility. Hepatic vitellogenin levels were increased significantly in males treated with 10, 50 and 100microg/l of 4-NP. In the F(1) generations, the hatchability and time to hatching of embryos in the 100microg/l treatment group were adversely affected, and 2-7microg 4-NP/g egg was found in spawned eggs (the bioconcentration factor: 30-100). These results indicate that (1) 4-NP adversely affected the reproduction (fecundity and fertility) of adult medaka, (2) 4-NP accumulated in eggs through maternal transfer and (3) these levels of 4-NP were associated with adverse effects in the F(1) offspring.  相似文献   
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Stakeholder groups, defined according to their transcendent values, have different concepts of sustainability. Their prioritizations of individual, family, collective, and local and global environmental issues also differs. Given this, the metrics required for a given sustainable development path are subjective. Therefore, the questions of who should define ecometrics, their transparency, number, state of aggregation, standardization, and benchmarking are questions that require an enfranchised multi-stakeholder debate. At present, corporations have been asked to bear the burden of environmental reporting and eco-indicators have been established to account for material intensity, energy consumption and waste or toxic releases, among other factors. However, the links among these local-, product-, or service-based microecometrics and global states such as temperatures or atmospheric concentrations have yet to be established. The relationship of macroecometrics to individual definitions of sustainable development also has not been addressed. This article summarizes four plenary lectures given at ECOMETRICS '98 in Lausanne, Switzerland. The workshop involved forty participants from industry, academic and government organizations representing seven countries and three continents.  相似文献   
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The hydrothermal treatments were conducted prior to the carbonization of oak woods and the obtained charcoals were activated using carbon dioxide or water vapor. The hydrothermal treatments brought about the elutions of acid-soluble lignin fractions as well as hemicellulose fractions accompanied with the decomposition of lignin carbohydrate complexes in the cell walls, which lowered not only the carbon yield of charcoal but also the crystal parameters for the carbon crystallites. However, the activated carbons (AC) produced via the hydrothermal pre-treatment showed superior adsorption properties especially for the adsorptions of 2-methylisoborneol and geosmin as compared with the untreated commercial AC. The hydrothermal treatments prior to the carbonization have some potential to increase the fractions of meso-pores effective for the adsorption of globular shaped molecules.  相似文献   
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It is required to replace the aluminum fluoride coating, which is a popular lubricant for aluminum alloy cold forging in Japan, with environmentally friendly lubricants, because the aluminum fluoride coating has high environmental risks and needs much expense. Evaluations of lubrication performance are necessary before lubricant replacement. The authors proposed new friction test based on combined forward spline-backward can extrusion. It can realize large surface expansion, which is a characteristic of aluminum cold forging. In the present paper, a double-layer-type environmentally friendly solid lubricant film and the aluminum fluoride coating were applied to a precipitation hardened aluminum alloy. The lubrication performance was evaluated by the friction test. The double-layer-type lubricant showed superior performance enough for the replacement. The effect of surface treatment applied to workpiece on the lubrication performance was also investigated. The surface asperity generated by a wet-blasting showed high pickup resistance and low friction.  相似文献   
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Antarctic krill, Euphausia superba, hatched from eggs and maintained for four years, were sampled periodically for age-pigment analysis. Extractable pigments from the eye and eyestalk ganglia were quantified using fluorescence intensity and standardised against protein. Three peak fluorescence intensities were detected at wavelengths of excitation 280 nm, emission 625 nm (pigment 1); excitation 355 nm, emission 510 nm (pigment 2); and excitation 463 nm, emission 620 nm (pigment 3). There was a positive correlation between the quantity of pigments 1 and 3 and the age of Antarctic krill. A model was developed to predict age from pigment 3 and to compare it with other age proxies (carapace length and eyeball diameter). The quantity of pigment 3 was the best predictor of age. The pigment method can discriminate between similar sized krill aged 12 and 36 months. Age pigments provide an improved tool for age estimation in Antarctic krill, particularly if used in conjunction with other demographic information.  相似文献   
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