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31.
Edmonds Jae Wise Marshall Pitcher Hugh Richels Richard Wigley Tom MacCracken Chris 《Mitigation and Adaptation Strategies for Global Change》1997,1(4):311-339
We report results from the application of an integrated assessment model, MiniCAM 1.0. The model is employed to explore the full range of climate change implications of the successful development of cost effective, advanced, energy technologies. These technologies are shown to have a profound effect on the future magnitude and rate of anthropogenic climate change. We find that the introduction of assumptions developed by a group of ‘bottom-up’ modelers for the LEESS scenarios into a ‘top-down’ model, the Edmonds-Reilly-Barns Model, leads to ‘top down’ emissions trajectories similar to those of the LEESS. The cumulative effect of advanced energy technologies is to reduce annual emissions from fossil fuel use to levels which stabilize atmospheric concentrations below 550 ppmv. While all energy technologies play roles, the introduction of advanced biomass energy production technology is particularly important. The consideration of all greenhouse related anthropogenic emissions, and in particular sulfur dioxide, is found to be important. We find that the consideration of sulfur dioxide emissions coupled to rapid reductions in carbon dioxide emissions leads to higher global mean temperatures prior to 2050 than in the reference case. This result is due to the short-term cooling impact of sulfate aerosols, which dominates the long-term warming impact of CO2 and CH4 in the years prior to 2050. We also show that damage calculations which use only mean global temperature and income may be underestimating damages by up to a factor of five. Disaggregating income reduces this to a factor of two, still a major error. Finally, the role of the discount rate is shown to be extraordinarily important to technology preference. 相似文献
32.
Otto Kandler 《Die Naturwissenschaften》1981,68(4):183-192
The determination of the sequence similarity of the ribosomal 16S RNA of many bacteria and a few higher organisms has shown that the methanogenic, halophilic, and acido-thermophilic organisms are phylogenetically separated from the kingdoms of the Eubacteria and Eukaryotes thus representing a third kingdom called "Archaebacteria". Many biochemical and molecular biological features support this conclusion. 相似文献
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36.
Unemployment effects of climate policy 总被引:1,自引:0,他引:1
This paper models the unemployment effects of restrictions on greenhouse gas emissions, embodying two of the most significant types of short-term economic imperfections that generate unemployment: sectoral rigidities in labor mobility and sectoral rigidities in wage adjustments. A labor policy is also analyzed that would reduce the direct negative economic effects of the emissions restrictions.The politics of limiting greenhouse gas emissions are often dominated by relatively short-term considerations. Yet the current economic modeling of emissions limitations does not embody economic features that are likely to be particularly important in the short term, in particular, the politically sensitive unemployment rate. Moreover, only a few of these studies also consider policies that would offset the negative direct economic effects of emissions restrictions. For plausible estimates of the parameters, the model shows that, with the labor market imperfections, if there were no offsetting policies, the reductions in GNP in the U.S. in the first 10 years after emissions restrictions were imposed would be as much as 4%. However, if there were two policies, instead of just one: a counteracting labor market policy, as well as the emissions restrictions, the negative direct economic effects could be completely eliminated. 相似文献
37.
Yves Dumez Marc Dommergues Marie-Claire Gubler Victor Bunduki Francoise Narcy Martine Lemerrer Laurent Mandelbrot Richard Berkowitz 《黑龙江环境通报》1994,14(2):141-144
A case of Meckel—Gruber syndrome was diagnosed by embryoscopy at 10 menstrual weeks, allowing for early termination of pregnancy. Post-mortem examination confirmed the presence of polydactyly and bilateral cystic lesions of the mesonephros and metanephros. Both the forming nephrons and the collecting ducts were involved in the formation of renal cysts. 相似文献
38.
A Framework for Monitoring and Evaluating Carbon Mitigation by Farm Forestry Projects: Example of a Demonstration Project in Chiapas,Mexico 总被引:1,自引:0,他引:1
De Jong Ben H.J. Tipper Richard Taylor John 《Mitigation and Adaptation Strategies for Global Change》1997,2(2-3):231-246
Mitigation and Adaptation Strategies for Global Change - In Mexico an estimated 4.5 × 106ha are available for farm forestry, while up to 6.1 × 106 ha could be saved from deforestation by... 相似文献
39.
David M. Sherer MD James R. Woods Jr Jacques S. Abramowicz John A. Dipreta Leon A. Metlay Richard Jaffe 《黑龙江环境通报》1993,13(12):1079-1084
Although malignant transformation of fetal cervical teratoma is extremely rare, perinatal morbidity is high and usually related to the size of the tumour, which may compromise fetal swallowing and subsequently lead to upper airway obstruction. We present a case in which mid-trimester serial sonography demonstrated markedly rapid early growth of a lesion of this type between 17 and 19 weeks' gestation indicating the aggressive nature of this tumour, assisting parental decision to terminate the pregnancy. Histopathology confirmed grade 3 immaturity of the lesion. 相似文献
40.
David Jeffrey Gray D.O. Haynes B. Robinson James Malone Richard B. Thomson Jr 《黑龙江环境通报》1992,12(2):111-117
Infections in pregnancy with Ureaplasma urealyticum have been associated with a wide range of adverse outcomes, such as early abortion, stillbirth, prematurity, and neonatal morbidity and mortality. Causality has been difficult to demonstrate secondary to the high prevalence of asymptomatic lower genital tract (LGT) colonization and culture data from inaccessible or potentially contaminated sites. Between 1985 and 1989, 2461 second-trimester genetic amniocenteses were evaluated at the cytogenetics section of the Children's Hospital Medical Center of Akron. All were cultured for the genital mycoplasmas: Mycoplasma hominis and Ureaplasma urealyticum. A total of nine patients were positive, all for Ureaplasma urealyticum, with one patient excluded because of subsequent therapeutic abortion. In addition, complete follow-up data, such as indication for amniocentesis, serum alpha-fetoprotein levels, gestational age at parturition, and out- come of pregnancy, were available on 86 Ureaplasma-negative (U –) patients during an approximate 2-year span within the time-frame of the study. This was in part due to physician response to a questionnaire sent after amniocentesis. Of the eight positive cultures, 100 per cent were associated with an adverse outcome, defined as fetal loss or premature delivery. This was significant compared with the U–group (p<0.001) with a more than eight times greater risk of adverse outcome. Six (75 per cent) resulted in spontaneous miscarriage within 4 weeks of amniocentesis and at less than 21 weeks' gestation. Two (25 per cent) delivered prematurely, with one (12.5 per cent) neonatal death at 24+ weeks. Histological examination of all eight placentae and the seven fetuses revealed a 100 per cent incidence of chorioamnionitis and pneumonia, respectively. In addition, in four of the five cases (80 per cent), cultures were positive for Ureaplasma urealyticum in pure culture from either placenta, fetal lung, or both tissues. The remaining case (20 per cent) was negative for aerobes, anaerobes, and mycoplasmas. The study demonstrates a significant association and supports a causal relationship between isolation of Ureaplasma from mid-trimester amniotic fluid with fetal wastage and premature birth. 相似文献