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961.
为构建辽宁省典型城市道路尘源成分谱,分别采集了鞍山市和盘锦市道路尘样品,分析了其化学组分特征,用富集因子法和比值法分析了其主要来源,用分歧系数法分析了两个城市成分谱的相似度.结果表明:盘锦市和鞍山市道路尘PM2.5中的化学组成以有机碳组分(OC)和地壳类元素(Al、Ca、Mg、Fe和K)为主.除Cu和V元素外,其余元素均表现为鞍山市的富集因子大于盘锦市.由比值法可得,盘锦市和鞍山市OC/EC分别为(13.20±6.26)和(3.94±0.63),均存在二次污染现象;NO3-/SO42-的均值分别为(0.52±0.55)和(0.46±0.13),说明其道路尘PM2.5受固定源影响更大.盘锦市与鞍山市道路尘成分谱分歧系数为0.354,说明两个源成分谱可能相似.  相似文献   
962.
Using previously published histological data on multiple, monthly samples of Sardina pilchardus collected in the central Aegean and Ionian Seas (September 1999–August 2000, and November 2000–February 2001), the Mediterranean sardine was treated as a case study to investigate the biological characteristics of ephemeral spawning aggregations in multiple-spawning clupeoids. Actively spawning (Day0) females in the Mediterranean sardine, i.e., the daily class of spawners caught a few hours prior, during, or after the spawning act, were shown to separate spatially from late (Day1+) spawners and non-spawning females, taking with them a large proportion of conspecific males which were also in advanced spawning condition and in better somatic condition compared to the remaining population. In addition, information from 28 stocks of multiple-spawning clupeoids from a wide range of geographic locations, belonging to 14 species and 2 families (Engraulidae and Clupeidae), was reviewed and analyzed pertinent to the formation of ephemeral spawning aggregations. Results from the latter analysis indicated similar patterns of spatial segregation of Day0 spawners in the reviewed clupeoid stocks as in the Mediterranean Sardine, which strongly suggested that the formation of ephemeral spawning aggregations is a common behavioral trait among multiple-spawning clupeoids. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
963.
将20头荷斯坦产奶奶牛随机分为对照组和试验Ⅰ~Ⅲ组,对照组饲喂全混日粮(TMR),试验Ⅰ组每头奶牛每天饲喂TMR加150.0 g复合脂肪酸,试验Ⅱ组每头奶牛每天饲喂TMR加150.0 g乳酸,试验Ⅲ组每头奶牛每天饲喂TMR加150.0 g复合脂肪酸/乳酸(质量比为1∶1),分析探讨了复合脂肪酸和乳酸对奶牛粪尿、氮、总磷排泄量和CH4释放量的影响.结果表明,相比对照组,试验Ⅲ组1头奶牛1年CH4释放量减少30.64 kg,粪尿、氮、总磷排泄量分别减少1.43 t、28.32 kg和2.36 kg,标准乳(FCM)提高3.28%.在奶牛饲料中添加乳酸和复合脂肪酸的混合酸,能有效抑制奶牛对土壤、水体及空气的污染,显著提高奶牛的生态效益和经济效益.  相似文献   
964.
Anarchy, where honeybee workers produce males in the presence of a queen, is extremely rare in natural honeybee populations, suggesting that there are colony-level costs associated with being anarchistic. Yet, no significant costs have yet been identified. A possible reason for this may be that researchers have only focused on the behaviour of anarchistic workers, which have been shown to perform worker-tasks as do wild-type workers. Possibly, therefore, costs associated with anarchy should be sought in anarchistic queens and not workers. A potential cost could be a lower survival rate of eggs laid by anarchistic queens perhaps because their egg-marking signal is not as clear as that of a wild-type queen. In this paper, we determined the removal rate of eggs laid by anarchistic queens in standard worker-policing bioassays. Our results show that eggs laid by anarchistic queens are removed at a higher rate than eggs laid by wild-type queens. This does not seem to be due to differences in hydrocarbons found on the surface of eggs, as both egg types showed the same alkanes and alkenes in similar proportions. We postulate that higher removal rates of queen-laid eggs due to recognition errors may be one reason that anarchy is rare in natural honeybee populations.  相似文献   
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966.
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968.
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications discussed the possibility exogenous magnetic and electromagnetic fields to initiate effects on various biological processes, which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields are increasingly utilized for treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs to be developed in parallel with clinical applications. Magnetotherapy provides a non-invasive, safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of injury. Unfortunately, there are many obstacles that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for tissue repair are subjects of this review.  相似文献   
969.
This article analyses the application of voluntary environmental agreements (VEAs) in watershed protection in Costa Rica. Next to an involvement of private energy firms, the Costa Rican state, and farmers, the participation of NGOs is a remarkable feature. From an analysis of these multi-stakeholder arrangements, it is concluded that these arrangements bring benefits to all actors involved. VEAs have been able to grow as powerful policy instruments, generating positive environmental effects. Essential is their embedded ness in a broader set of environmental policies, especially related to forest management Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
970.
In order to determine the potential for sustainable regional development of the Caspian coastal zone, a study was made for the Khachmaz–Absheron zone of Azerbaijan. An evaluation was performed to assess the anthropogenic load on landscapes. Using the 8-point scale offered by Isachenko [2001, Ecological Geography of Russia, Saint Petersburg University Press, Saint Petersburg] for the indicators of agricultural, industrial, urban and integral anthropogenic loads, we did a preliminary ranking of the provinces in the Khachmaz–Absheron zone of Azerbaijan for the each indicator taken separately. Vital statistics were used as a supplementary indicator of environmental conditions in the region. By comparing the data for provinces with each other and the data on Azerbaijan average, we have classified the provinces into 4 groups according to specific combinations of the indicators. Each group of provinces has distinctive environmental conditions and features for sustainable development. The classification makes it possible to develop certain recommendations for the regional sustainable development. Measures to be implemented within the Azerbaijan State Program on Social and Economic Development of Regions are also discussed. In the Khachmaz province, production of ecologically pure products is highly recommended. Special attention should be given to the development of tourism and recreational institutions in the Khachmaz, Khizi and Devechi provinces. Recommendations for these provinces include further development of industry on the basis of modern safe technologies. The irrigation and drainage networks should be reconstructed. The reconstruction will make it possible to reduce water loss and to increase the productivity of agriculture. In the Absheron province, Baku and Sumgait cities environmental systems are overloaded, and so the works at highly polluting enterprises must be stopped, the enterprises have to be re-equipped (old filters must be changed first of all) or relocated from the area (a decrease of environmental risk should be in the focus of attention). For improving of air quality, green areas should increase. There is a need to reduce urban traffic density and to reconstruct highways. Use of old vehicles must be forbidden or restricted, and transition to environmentally friendly fuel should be supported in every way possible. It is necessary to bring the waste management system and sanitary landfills up to international standards, and to improve the water supply and sewerage systems.  相似文献   
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