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31.
文章介绍了一种生物除臭的方法,这种方法是将装有碳质填料的反应包悬挂于好氧池中,反应包在好氧池中,历经曝气挂膜20~30天;就可以将装有碳质填料的反应包/或碳质填料放于生物除臭装置内;然后向生物除臭装置通入湿润的臭气,就可以将其生成水、二氧化碳、硫酸、硝酸和亚硝酸.使臭气被氧化,转化成无污染的物质,由于它的转化效率高,符合现代生产的高效性,因此一定会在生产实际中受到欢迎.  相似文献   
32.
瞿贤  周珉  刘琴 《环境工程》2013,(Z1):40-43
实验利用复合膜生物反应器处理以甘油为原料制备环氧氯丙烷产生的废水,考察了不同进水COD、水力停留时间以及盐度对处理能力的影响,并进行盐度冲击实验。生物处理后出水进行了深度处理的研究。结果表明:进水COD对处理能力影响较小;适当延长水力停留时间能优化出水水质;废水盐度高于22g/L时会对微生物产生抑制作用;深度处理能进一步降低出水COD;微生物通过一定时间的驯化期能适应并处理高盐度废水。  相似文献   
33.
二氧化氮是室内空气的主要污染物之一。从技术层面上介绍了室内空气的二氧化氮采集与测量方法,重点介绍了被动式采样法、分光光度法、化学发光法和库伦原电池法。详细分析了影响室内二氧化氮浓度的主要因素及室内二次污染的相关研究,归纳了其对人类健康的不良影响,并提出室内二次污染是未来的重要研究方向。  相似文献   
34.
Acidobacteria is one of the most dominant and abundant phyla in soil,and was believed to have a wide range of metabolic and genetic functions. Relatively little is known about its community structure and elevational diversity patterns. We selected four elevation gradients from 1000 to 2800 m with typical vegetation types of the northern slope of Shennongjia Mountain in central China. The vegetation types were evergreen broadleaved forest,deciduous broadleaved forest,coniferous forest and sub-alpine shrubs. We analyzed the soil acidobacterial community composition,elevational patterns and the relationship between Acidobacteria subdivisions and soil enzyme activities by using the 16 S rRNA meta-sequencing technique and multivariate statistical analysis. The result found that 19 known subdivisions as well as an unclassified phylotype were presented in these forest sites,and Subdivision 6 has the highest number of detectable operational taxonomic units(OTUs). A significant single peak distribution pattern(P 0.05) between the OTU number and the elevation was observed. The Jaccard and Bray–Curtis index analysis showed that the soil Acidobacteria compositional similarity significantly decreased(P 0.01) with the increase in elevation distance. Mantel test analysis showed the most of the soil Acidobacteria subdivisions had the significant relationship(P 0.01) with different soil enzymes. Therefore,soil Acidobacteria may be involved in different ecosystem functions in global elemental cycles. Partial Mantel tests and CCA analysis showed that soil pH,soil temperature and plant diversity may be the key factors in shaping the soil Acidobacterial community structure.  相似文献   
35.
分析了安全生产标准化与其他管理体系的关系,并结合当前推进安全生产标准化工作的具体要求,阐述了安全生产标准化的作用。  相似文献   
36.
Agustinia ligabuei is an Early Cretaceous sauropod dinosaur from the northwest of Patagonia that is currently the topic of debate with respect to its phylogenetic position and atypical dermal armor. The presence of four morphotypes of laminar and transversely elongated putative osteoderms was used to consider Agustinia as an armored sauropod. Regarding the different hypotheses about the identity of the bony structures of Agustinia (e.g., osteoderms, cervical or dorsal ribs, hypertrophied elements), a comparative histological analysis has been carried out. Histological evidence is presented herein and reveals that none of the morphotypes of Agustinia shows a primary bone tissue formed by structural fiber bundles as in other sauropod dinosaur osteoderms. Furthermore, on the basis of their gross morphology and microstructure, the bony structures originally classified as types 1 + 4 and 3 are more comparable respectively with dorsal and cervical ribs than any other kind of dermal or bony element. Due to poor preservation, the nature of the type 2 cannot be assessed but is here tentatively assigned to a pelvic girdle element. Although a phylogenetic reassessment of Agustinia is not the purpose of this paper, our paleohistological analyses have broader implications: by not supporting the dermal armor hypothesis for Agustinia, its inclusion in Lithostrotia is not justified in the absence of other diagnostic features.  相似文献   
37.
Flower symmetry is considered a species-specific trait and is categorized in asymmetry, actinomorphic symmetry, bisymmetry and zygomorphic symmetry. Here we report on the intra-individual variation of flower symmetry in the genus Saxifraga and the influence of light, gravity and intrinsic factors on the development of flower symmetry. We tested five species—Saxifraga cuneifolia, Saxifraga imparilis, Saxifraga rotundifolia, Saxifraga stolonifera and Saxifraga umbrosa—concerning six flower parameters—angles between petals, petal length, petal pigmentation, angular position of carpels, movement of stamens and (only for S. imparilis and S. stolonifera) the length of the two lower elongated petals in regard to their position towards the stem. Specimens of all species were tested on a vertical clinostat as a gravity compensator, on a horizontal clinostat as a light incidence compensator and on a stationary control. The results show that the angle of incident light has no apparent impact on flower symmetry, whereas gravity affects the angular position of petals in S. cuneifolia and S. umbrosa and the petal colouration in S. rotundifolia. In S. cuneifolia and S. umbrosa, the absence of directional gravity resulted in the development of actinomorphic flowers, whereas the corresponding control flowers were zygomorphic. The development of flowers in S. rotundifolia was not altered by this treatment. The length of the two elongated petals in S. stolonifera and S. imparilis was not affected by gravity, but rather was determined by position of the flower within the inflorescence and resulted in asymmetrical flowers.  相似文献   
38.
Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.  相似文献   
39.
In neonate ruminants, the acoustic structure of vocalizations may depend on sex, vocal anatomy, hormonal profiles and body mass and on environmental factors. In neonate wild-living Mongolian gazelles Procapra gutturosa, hand-captured during biomedical monitoring in the Daurian steppes at the Russian-Mongolian border, we spectrographically analysed distress calls and measured body mass of 22 individuals (6 males, 16 females). For 20 (5 male, 15 female) of these individuals, serum testosterone levels were also analysed. In addition, we measured relevant dimensions of the vocal apparatus (larynx, vocal folds, vocal tract) in one stillborn male Mongolian gazelle specimen. Neonate distress calls of either sex were high in maximum fundamental frequency (800–900 Hz), but the beginning and minimum fundamental frequencies were significantly lower in males than in females. Body mass was larger in males than in females. The levels of serum testosterone were marginally higher in males. No correlations were found between either body mass or serum testosterone values and any acoustic variable for males and females analysed together or separately. We discuss that the high-frequency calls of neonate Mongolian gazelles are more typical for closed-habitat neonate ruminants, whereas other open-habitat neonate ruminants (goitred gazelle Gazella subgutturosa, saiga antelope Saiga tatarica and reindeer Rangifer tarandus) produce low-frequency (<200 Hz) distress calls. Proximate cause for the high fundamental frequency of distress calls of neonate Mongolian gazelles is their very short, atypical vocal folds (4 mm) compared to the 7-mm vocal folds of neonate goitred gazelles, producing distress calls as low as 120 Hz.  相似文献   
40.
In temperate climates, the initiation and termination of diapause synchronize the stress-tolerant stage with the stressful season and reproduction with the non-stressful season in many insects. Synchronization is often regulated by photoperiodism.Voltinism and the ultimate size of adults are also important determinants for their lifecycle, and different diapause stages and voltinism patterns are known in crickets.Here, we investigated the life history of the African cricket Gryllus argenteus from Malawi, which is a typical arid tropical highland. The climate is characterized by alternating arid and wet seasons, each of which lasts for half a year, and where the available heat mass is much less than lowlands at the same latitude. We first measured the nymphal duration at each rearing temperature and calculated the lower developmental threshold (t 0) to be 20.19 °C based on Ikemoto and Takai (2000) and 19.38 °C based on a conventional line-fitting method. These values are very high relative to many other insects. The local temperature in winter does not fall below 15 °C, but this is much higher than the lethal limit. This suggested that critical stress in this locality was not coldness but low precipitation in winter. We estimated, based both on local temperature change and the Ikemoto and Takai’s t 0, that G. argenteus required 3 years to complete its lifecycle unlike wet lowland species, where univoltinism or multi-voltinism are commonplace. Photoperiodism was observed in this species, but due to a lag between annual cycles in photoperiod, temperature, and humidity, photoperiodism alone cannot atune their lifecycle with local conditions.Synchronization in this species was achieved by three different adaptations: photoperiodism, high t 0, and large body size, which give it a long lifecycle. Although the species cannot achieve a univoltine lifecycle because of its high t0 value, it can escape from dry season by entering diapause at moderate temperatures, probably thereby achieving adaptive synchrony of lifecycle with both favorable and unfavorable seasons. A comparison between a conventional photothermogram and a newly formulated photohydrogram or photohygrogram demonstrates that even though sufficient heat is available, scarcity of water and thus scarcity of foliage should force the cricket to maintain diapause at intermediate temperature. The results suggested that high t 0, large body size, and multi-ennial lifecycle mutually affect each other and formulate a unique adaptation under such an extreme environment.  相似文献   
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