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241.
Maturity assessment of compost from municipal solid waste through the study of enzyme activities and water-soluble fractions 总被引:2,自引:0,他引:2
In this work the dynamics of biochemical (enzymatic activities) and chemical (water-soluble fraction) parameters during 100 days of municipal solid wastes composting were studied to evaluate their suitability as tools for compost characterization. The hydrolase (protease, urease, cellulase, beta-glucosidase) and dehydrogenase activities were characterized by significant changes during the first 2 weeks of composting, because of the increase of easily decomposable organic compounds. After the 4th week a "maturation phase" was identified in which the enzymatic activities tended to gently decrease, suggesting the stabilisation of organic matter. Also the water-soluble fractions (water-soluble carbon, nitrogen, carbohydrates and phenols), which are involved in many degradation processes, showed major fluctuations during the first month of composting. The results obtained showed that the hydrolytic activities and the water-soluble fractions did not vary statistically during the last month of composting. Significant correlations between the enzymatic activities, as well as between enzyme activities and water-soluble fractions, were also highlighted. These results highlight the suitability of both enzymatic activities and water soluble fractions as suitable indicators of the state and evolution of the organic matter during composting. However, since in the literature the amount of each activity or fraction at the end of composting depends on the raw material used for composting, single point determinations appear inadequate for compost characterization. This emphasizes the importance of the characterization of the dynamics of enzymatic activities and water-soluble fractions during the process. 相似文献
242.
Daniela Turchetti Elisabetta Razzaboni Hila Zomer Cesare Rossi Simona Ferrari Donatella Greco Claudio Graziano Giovanni Romeo Marco Seri 《黑龙江环境通报》2006,26(12):1156-1159
Angelman Syndrome (AS), characterized by mental retardation, absence of speech, seizures and motor dysfunction, is caused by genetic defects leading to loss of expression of the maternal copy of the chromosome 15q11–13 imprinted region. Most cases are sporadic, being caused by de novo deletion of maternal chromosome 15q11–13 (75%) or by paternal uniparental disomy (3–4%). Familial cases can occur, due to mutations in the UBE3A gene or in the imprinting center. We describe the case of a pregnant woman having two nephews with AS caused by a UBE3A mutation; lack of communication within the family led the woman to be completely unaware of the risk of disease recurrence until 15 weeks of gestation. UBE3A genetic testing revealed she carried the familial mutation 892–893delCT. Prenatal diagnosis was performed on amniotic fluid and demonstrated that the fetus had inherited the mutation. The unexpected diagnosis and the subsequent termination of the pregnancy caused the woman to undergo acute psychological distress showing relevant psychopathological symptoms. Nevertheless, at 2-year follow-up, adverse consequences were minimized, and the couple was planning a new pregnancy. Factors affecting the psychological outcome of abortion and the role of psychological support in reducing the risk of long-term unfavorable consequences are discussed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Claudia Borgioli Giovanni Maria Marchetti Felicitas Scapini 《Behavioral ecology and sociobiology》1999,45(2):79-85
Under stressful conditions (e.g. finding themselves on dry or moisture-saturated substrates) littoral talitrids (Crustacea,
Amphipoda) demonstrate zonal orientation, in which they must promptly reach the optimal zone of the beach, the wet fringe
near the shoreline. A relationship might therefore exist between the use of orientation and the frequency of such stressful
conditions in the natural environment. Moreover, the efficiency of orientation toward the sea could be related to the possibility
of using strategies other than zonal orientation in order to avoid stress. This study analysed the actual use and efficiency
of orientation under natural conditions of four Talitrus saltator (Montagu, 1808) populations from Mediterranean and northern European Atlantic coasts with different ecological features.
Orientation tests were carried out on the beach with all natural cues available. Then the same individuals underwent control
experiments to study their sun orientation far from the sea in an experimental arena. The following results emerge from the
comparison of the circular distributions: (1) marked differences among populations in the precision of zonal recovery under
natural conditions; (2) a common solar orientation capacity in the control tests far from the sea; (3) different orientation
choices of the same individuals according to the test conditions, natural or controlled. The habitat diversity of the four
populations (amount, distribution and kind of detritus and wrack on the beach, degree of coastal erosion, orientation of the
shoreline, human use of the beach) provides an ecological interpretation for the differences in orientation observed among
populations.
Received: 13 October 1997 / Accepted after revision: 26 April 1998 相似文献
246.
Dandolo Gramellini Stefania Fieni Giovanna Casilla Stefano Raboni Giovanni Battista Nardelli 《黑龙江环境通报》2007,27(10):956-959
Objectives and Methods Assuming that the rate of fetal loss after amniocentesis may be reduced in patients receiving antibiotic prophylaxis, we conducted a retrospective study on untreated versus treated patients receiving prophylactic antibiotics (amoxicillin/clavulanic-acid or azithromycin) and evaluated the fetal loss rate within the 22nd week of gestation, also with respect to the risk of spontaneous abortion, both preexisting and related to mid-trimester amniocentesis. Results Spontaneous abortion occurred in 22 cases out of 1744 (1.26%). The incidence of spontaneous abortion was 1.3% among patients treated with antibiotic prophylaxis and 1.2% among untreated patients. Between patients with risk factors that predated amniocentesis, the spontaneous fetal loss rate was 9.2% in untreated patients versus 2.3% in patients treated (p = 0.10). In patients with procedure-related risk factors at amniocentesis, the spontaneous abortion rate was, respectively, 2.2 and 1.2% (p = 0.72). Conclusion Our data demonstrate that antibiotic prophylaxis does not reduce the risk of spontaneous abortion within the 22nd week of gestation. Compared with untreated patients, patients treated with amoxicillin showed the lower fetal loss rate (1.16 vs 0.31%), but the difference was not statistically significant (odds ratio (OR) = 3.68, p = 0.32). The same was true for patients with preexisting risks (OR = 4.25, p = 0.10). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Patrizia Jereb Rita Cannas Porzia Maiorano Giambattista Bello Fulvio Garibaldi Marco Mereu Francesco G. Ancona Giovanni Ammendolia Pietro Battaglia Önder Duysak Hendrik Jan T. Hoving Eugenia Lefkaditou Marek R. Lipinski Riccardo Melis Panagiota N. Peristeraki Sergio Ragonese Teresa Romeo Alp Salman Begonia M. Santos Alberto Villari Danila Cuccu 《Marine Biology》2016,163(9):192