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861.
环境胁迫和乙烯对番茄PR-NP24基因表达的影响 总被引:1,自引:0,他引:1
根据已报道的番茄PR-NP24基因序列设计引物,经PCR克隆出长为477bp的番茄PR-NP24基因片段,以该片段制备探针,采用Northern杂交技术对该基因在番茄(WT)和乙烯反应突变体番茄(Nr,rin,T4B-11)中的表达进行了研究.杂交结果表明,该基因主要在果实和根部表达,伤害抑制WT、Nr番茄叶片中该基因的表达,而对rin番茄叶片无明显影响;干旱、淹水等环境胁迫和乙烯均能不同程度地诱导其表达,而在不同温度下,PR-NP24基因表达变化不大.图7参13 相似文献
862.
针对目前对于一般尘源控制研究较少,而系统研究粉尘的扬尘(尘化)机理的研究就更少这一状况,提出弄清尘化机理、从源头上控制是治理粉尘的首要问题,对粉尘颗粒作用力进行分析,特别就超细粉尘的扬尘机理提出相应的物理模型并进行初步研究.图1,参2. 相似文献
863.
Abstract: The 2010 biodiversity target adopted globally and in Europe is an important political commitment for improved biodiversity conservation and management. Whether or not it is achieved will be judged by a set of biodiversity indicators now under development. We reviewed the development of these indicators in Europe and globally, paying particular attention to the need to make the indicators relevant to the purpose; to distinguish between measures of pressure, state, and response; to design and validate the indicators in context; to ensure effective communication with relevant audiences; to turn lists of measures into simple or composite indicators; and to maximize the cost-effectiveness of the indicator process. We conclude that urgent steps are needed to complete the indicator set, reduce and refine the agreed measures, ensure that work is started soon so that reliable reporting occurs in 2010, and start soon on planning for subsequent assessments. 相似文献
864.
为保证本溪市水体达到水环境功能区规定的水质目标。需要建立污染物与水体水质之间的输入关系,掌握污染物在环境中迁移转化规律,由此确定本溪市区域水环境容量,及可利用的水环境容量,确定本溪市的污染物总量控制指标-满足本溪市社会经济发展对水环境的需要。达到水环境目标。是本溪市水污染物实施总量控制依据,是水环境管理基础。以此作为先决条件,指导本溪市经济发展和工业布局。 相似文献
865.
Dr. Sci. V. S. Baranov V. N. Gorbunova T. E. Ivaschenko N. Yu. Shwed N. S. Osinovskaya T. K. Kascheeva V. M. Lebedev A. V. Mikhailov V. G. Vakharlovsky T. V. Kuznetzova 《黑龙江环境通报》1992,12(7):575-586
From a total of 490 cystic fibrosis (CF) high-risk families under supervision (mostly Russian Slavs from the European part of the country), DNA data including both direct screening for some CF gene(CFTR)mutations(deIF508, G551D and 1677delTA) and allelic polymorphism studies with tightly CF linked DNA markers were collected from 261 families. All full families (129) and 86 CF families with a deceased index child were found to be either fully (42 per cent) or partially (40 per cent) informative for DNA analysis. Prenatal diagnosis (PD) was carried out in 161 CF families. Microvillar enzyme (MVE) assay was applied to all 140 PD at the second trimester either as a single test (88) or in conjunction with DNA analysis (52). The frequency of false-negative results of the MVE assay was 1.3 percent and that of false-positive results, as judged by the albumin meconium test, was 5.0 per cent. Ambiguous results of MVE analysis were found in 30 cases, 12 of which were verified by DNA analysis. Molecular diagnosis of CF at the first trimester was carried out in 21 cases and four pregnancies were terminated. Altogether, 39 pregnancies with a predicted high risk of CF fetuses were terminated. The low average frequency of delF508 in CF chromosomes of Russian Slavs (50 per cent), its remarkable inter-population variation, and the significant proportion of at-risk families without an affected child determine the necessity of combined molecular and biochemical (MVE assay) approaches for efficient prenatal diagnosis of CF in the former U.S.S.R. 相似文献
866.
867.
The challenge of making central requirements work at local levels is a common problem for environmental governance throughout
the world. Countries can learn from one another's approaches, but must understand the local context in which they are set.
This paper compares the features of the China and US environmental governance systems that need be understood by those working
between the systems. Key features include: (1) common values which shape the environmental governance choices in both countries,
but which may have different practical meanings in each country; (2) America's common law-based environmental governance system,
and China's civil law system, which involves plan(s) as well as law; (3) America's Federal central-local system, and China's
unitary central local system. This paper concludes by suggesting areas in which further comparative understanding may be of
value, including: (1) better understanding of the role of plan and law in China's governance system; (2) comparing the American
Federal-state agreement system for implementation of environmental law with the China central-local system of target responsibility
agreements for plan implementation; (3) improving understanding of nongovernmental resources needed to assure compliance with
environmental laws and plans; (4) identifying institutions that can coordinate central-local and cross-border environmental
governance. 相似文献
868.
Abstract: Remnant plants in urban fringes and native plants in gardens have the potential to contribute to the conservation of threatened plants by increasing genetic diversity, effective size of populations, and levels of genetic connectedness. But they also pose a threat through the disruption of locally adapted gene pools. At Hyams Beach, New South Wales, Australia, four bushland stands of the rare shrub, Grevillea macleayana McGillivray, surround an urban area containing remnant and cultivated specimens of this species. Numbers of inflorescences per plant, fruits per plant, and visits by pollinators were similar for plants in urban gardens and bushland. Urban plants represented a substantial but complex genetic resource, displaying more genetic diversity than bushland plants judged by He , numbers of alleles per locus, and number of private alleles. Of 27 private alleles in urban plants, 17 occurred in a set of 19 exotic plants. Excluding the exotic plants, all five stands displayed a moderate differentiation ( FST = 0.14 ± 0.02), although the urban remnants clustered with two of the bushland stands. These patterns may be explained by high levels of selfing and inbreeding in this species and by long-distance dispersal (several seeds in the urban stand were fathered by plants in other stands). Genetic leakage (gene flow) from exotic plants to 321 seeds on surrounding remnant or bushland plants has not occurred. Our results demonstrate the conservation value of this group of urban plants, which are viable, productive, genetically diverse, and interconnected with bushland plants. Gene flow has apparently not yet led to genetic contamination of bushland populations, but high levels of inbreeding would make this a rare event and difficult to detect. Remnant plants in urban gardens could successfully contribute to recovery plans for endangered and vulnerable species. 相似文献
869.