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91.
An Eco-balance of a Recycling Plant for Spent Lead–Acid Batteries   总被引:2,自引:0,他引:2  
This study applies Life Cycle Assessment (LCA) methodology to present an eco-balance of a recycling plant that treats spent lead–acid batteries. The recycling plant uses pyrometallurgical treatment to obtain lead from spent batteries. The application of LCA methodology (ISO 14040 series) enabled us to assess the potential environmental impacts arising from the recycling plants operations. Thus, net emissions of greenhouse gases as well as other major environmental consequences were examined and hot spots inside the recycling plant were identified. A sensitivity analysis was also performed on certain variables to evaluate their effect on the LCA study. The LCA of a recycling plant for spent lead–acid batteries presented shows that this methodology allows all of the major environmental consequences associated with lead recycling using the pyrometallurgical process to be examined. The study highlights areas in which environmental improvements are easily achievable by a business, providing a basis for suggestions to minimize the environmental impact of its production phases, improving process and company performance in environmental terms.  相似文献   
92.
The purpose of this study was to find out possible differences in prenatal diagnosis (PD) by amniocentesis or chorionic villus sampling and ultrasound examination before 16 weeks' gestation (early ultrasound examination, EUE), according to area of residence and level of education of the mothers. Data come from a multicentre study in Italy involving 43 maternity hospitals (Mercurio project) and were collected through structured interviews a few days after delivery. Study subjects were 1541 mothers of single non-malformed infants born between April 1992 and March 1994. Overall, the incidence of PD and EUE was 5.8 and 80 per cent, respectively. After adjustment for maternal age and other possible confounders, the odds ratios for PD were 2.19 (95 per cent confidence interval (CI)=1.26–3.81) when women residing in the northern regions were compared with those residing in the southern regions, and 2.06 (95 per cent CI=1.12–3.79) and 4.08 (95 per cent CI=1.97–8.42) when women with medium and high levels of education were compared with those with low level. For EUE, the odds ratios were 1.77 (95 per cent CI=1.32–2.36) and 2.88 (95 per cent CI=1.56–5.29) when comparing women with medium and high levels of education with those with low level. No relationship was found between area of residence and EUE. These geographical and social inequalities in prenatal care in Italy should be taken into account for the organization, delivery, and evaluation of pregnancy services in the coming years.  相似文献   
93.
To optimize fitness, organisms may have to trade the number and quality of individual offspring against their own condition and survival. Limiting micronutrients such as antioxidants may be crucial to this trade-off. We investigated whether vitamin E, a major antioxidant in the diet of vertebrates, is limiting to barn swallow (Hirundo rustica) nestlings. We manipulated brood size to alter the intensity of sib–sib competition and supplemented nestlings with two different physiological doses of vitamin E while establishing a control group. Treatment effects were measured on body mass and size, feather growth, T cell-mediated immune response and hematocrit. Supplementation with vitamin E at intermediate physiological doses improved nestling mass and condition and feather growth, whereas higher physiological doses did not enhance offspring quality compared to a control treatment. The positive effects of vitamin E on body mass and condition were only detectable from days 6 to 10 when maximum growth rate is attained. Experimental enlargement of broods reduced body mass and size and T cell-mediated immune response only during the late nestling period. The effect of vitamin E supplementation did not depend on brood size manipulation, as revealed by the nonsignificant statistical interaction. This result contradicts the hypothesis that availability of vitamin E depends on intrabrood competition and instead suggests that it depends on concentration of vitamin E in the insect prey of swallows. Thus, antioxidants may be available in limited amounts to barn swallow nestlings and such limitation affects growth. In addition, present results confirm that barn swallow parents trade progeny number against growth and immunity of individual offspring.  相似文献   
94.
The conventional (hot pressing or HP) and the novel (spark plasma sintering or SPS) consolidation techniques were compared when processing Ti–Al2O3–TiC powders obtained by self-propagating high-temperature synthesis (SHS). It was found that the two different methods are able to produce similar materials, in some cases (Vickers hardness and wear rate) slightly better for SPSed samples. However, SPS does not need sintering temperatures as high as HP to obtain fully dense products. Most significantly, processing times were strongly reduced when adopting the SPS technique instead of HP, i.e. 4–7 min and about 5 h, respectively. Finally, when the total energies required during each SPS or HP experiment were compared, it was found that the use of the SPS technology allowed for an energy saving in the order of 90–95%. This fact makes SPS significantly advantageous from environmental and economical points of view compared to HP.  相似文献   
95.
In diverse taxa, offspring solicit parental care using complex displays, which may evolve as reliable signals of condition or as mechanisms to manipulate parental investment. Differential sex allocation may therefore result from adaptive parental decisions or sex-related variation in competitive ability or because of sex-related asymmetries in kin selection. Under normal food provisioning, female barn swallow (Hirundo rustica) nestlings begged more loudly but did not receive more food than male nestlings. After food deprivation, begging call loudness of males but not females increased. Begging loudness positively predicted the number of feedings received by the nestlings, and males gained more mass than females after food deprivation. Male nestlings are more severely affected by chronic food reduction and may therefore accrue a larger benefit compared to females by increasing their food intake under short-term conditions of food scarcity. These results suggest that either females do not increase begging intensity to favour male broodmates which are more vulnerable to prolonged food stress, or that males prevail in scramble competition despite being similar in size to females.  相似文献   
96.
The impact of social movements as a major environmental influence in the evolution of career consciousness was analysed based on extensive interviews of women flight attendants. The aim was to elicit the women's view of their work lives over the past two decades. Flight attendants working in the 1960s entered with the expectation of a short-term job. From their accounts of personal development and from reviews of newspaper accounts, court cases and union documents, the influence of three major social movements became apparent. The Civil Rights Movement prompted flight attendants to challenge the legality of airline rules that prevented them from working past age 32. The Women's Movement reinforced the value and seriousness of women's commitment to a career and enabled flight attendants to challenge traditional notions of the incompatibility of occupation and family. The Occupational Health Movement, by addressing the collective problems of creating a healthy work environment, mobilized women flight attendants to recognize their long-term career investment. The findings suggest that social movements provide an additional dimension that is relevant for the future study of career development and continuing occupational socialization.  相似文献   
97.
The radiocarbon content in creosote bush in the greater Los Angeles area has been found to reflect the distribution of smog. Indications are that smog in the even larger air basin of the San Joaquin Valley of California may be caused in part by recent biospheric emissions rather than by fossil fuel combustion alone.  相似文献   
98.
Noroviruses are recognized as the leading cause of human acute viral gastroenteritis worldwide. The rate of outbreaks on cruise ships has grown significantly in recent years. Given the potentially harmful consequences of outbreaks for passengers and crewmembers and the subsequently high costs for cruise companies, disease outbreaks on cruise ships represent a serious public health issue. The aim of our study was to systematically review published studies related to Norovirus outbreaks on commercial cruise ships. We searched the PubMed and Scopus scientific databases. We included eligible studies published from January 1990 to July 2013 that were written in English and described infectious episodes involving at least two passengers and/or crewmembers on a commercial cruise ship. As a result, 15 studies and seven reviews met the inclusion criteria, describing a total of 127 outbreaks. The majority of the cases were reported in Europe and the USA, affecting <1 to 74 % of the embarked passengers. In the majority of the studies, stool samples and/or serum specimens from ill passengers were collected and tested for laboratory confirmation. Twelve studies reported that an ad-hoc questionnaire was administered. Fifteen studies investigated the possible source of infection which was contaminated food in the majority of cases. Our findings suggest a strong need for the monitoring and implementation of preventive measures in semi-closed communities, such as cruise ships. It would be advisable to strengthen all relevant initiatives in order to improve the detection of, response to and control of Norovirus outbreaks on cruise ships.  相似文献   
99.
Environmental Science and Pollution Research - In this study, the anthropogenic contamination in Trasimeno lake (Central Italy) was investigated using three sediment cores spanning over the last...  相似文献   
100.

Background, aim, and scope  

Fishery wastewater treatment can be compromised due to seasonal production. The use of sequencing batch reactors is not completely successful, despite flexibility being one of the principal advantages. Most research on activated sludge is performed using synthetic wastewater to ensure a stable and constant feed. The current work compared biomass morphology and settling ability using image analysis of synthetic and real fishery wastewaters, with and without NaCl addition.  相似文献   
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