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401.
Koustubh M. Vaze Nisha N. Kannan L. Abhilash Vijay Kumar Sharma 《Die Naturwissenschaften》2012,99(11):967-971
Morning and evening chronotypes of sleep/wake cycles in humans are often metaphorically termed as ‘larks’ and ‘owls’. We derived Drosophila populations early and late, displaying lark- and owl-like emergence chronotypes by imposing selection for adult emergence during morning and evening hours. Preference for morning and evening emergence in these populations was accompanied by divergence in their circadian period (τ) and photic phase response curve. To test if lark- and owl-like emergence chronotypes displayed by these flies under weak environmental cycles of the laboratory would also persist in nature where several zeitgebers are present in the strongest form, we examined the emergence rhythm of early and late flies under semi-natural conditions. The early and late flies not only continued to exhibit divergent emergence waveforms under semi-natural conditions, the differences became even more prominent. However, phases of early and late emergence waveforms did not match natural morning and evening transitions, unlike that observed under laboratory conditions. These results thus provide evidence consistent with the notion that chronotypes are the result of interactions between circadian clocks and natural environmental cycles. 相似文献
402.
The need for environmental and urban planning reached a critical point in the year 2007, when one-half of the world's population
could be defined as living in cities. Urbanisation in India is also increasing at a fast rate. Urban chaos in India, emanating
from the continuous ignorance of fragile ecosystems, calls for the reshaping of existing cities as ‘eco-cities’. The ‘eco-city’—a
well-known concept in the western world—is new to the Indian context. While western connotations of eco-cities should not
be discarded outright in the context of India, core concerns vary significantly for obvious reasons. Recognising two facts—firstly,
eco-city development is altogether a fresh approach to human settlement development in India, and, secondly, the manifold
increase in the vulnerability of cities—this paper discusses documented good practice, reinforcing evolution towards the eco-city
vision. Lessons drawn from the examples cited are further deconstructed in the light of their contribution to urban risk reduction,
which provides direction to appreciating the ‘disaster-resilient eco-community’ concept in Puri, a coastal city in India.
Further, this paper attempts to unravel existing community-based practices in Puri, which are boon to the local environment
and invariably reduce disaster risk. These seemingly modest neighbourhood initiatives symbolise immense societal wealth, which
can be calibrated appropriately for reducing urban environmental risk as well. This paper also illustrates how a ‘disaster
resilient eco-community’ approach is inevitable in the present and future contexts not only to preserve sustainable development
gains but also to secure human well-being. 相似文献
403.
Microbial degradation of pyridine using Pseudomonas sp. and isolation of plasmid responsible for degradation 总被引:11,自引:0,他引:11
Mohan SV Sistla S Guru RK Prasad KK Kumar CS Ramakrishna SV Sarma PN 《Waste management (New York, N.Y.)》2003,23(2):167-171
Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine. 相似文献
404.
405.
A. U. Mahajan C. S. Sunil Kumar Pawan Kumar B. Chakradhar S. D. Badrinath 《Environmental monitoring and assessment》1996,41(3):203-217
The Andman and Nicobar archipelago comprises of about 556 small and big islands covering an area of 8493 sq. kms in the Bay of Bengal. The very remoteness of these islands from the mainland has preserved their pristine environment and spectacular natural beauty. The Andman and Nicobar Administration is going for major developmental projects to cope with the increasing needs of the people, which ultimately results in significant changes in environmental quality. This paper describes the existing environmental quality around Port Blair city, which will give baseline scenario to assess the environmental impacts due to developments in the future.In order to monitor the air quality of the region, sampling stations were selected based on the locations of various industries and domestic activities. Suspended Particulate Matter (SPM), Sulphur dioxide (SO2) and Nitrogen Oxides (NOx) were monitored for a period of one month during winter season. In addition, micrometeorological data, viz. wind speed and direction were also recorded and analysed to obtain the representative meteorological scenario of the air basin. The monitored values of ambient air quality was found to be within the NAAQ standards of India.Similarly, noise levels were also measured at various locations viz., residential areas, commercial centres, villages, stone quarry sites and construction sites. Noise levels were found to exceed the standards at stone quarry, construction sites and other locations.Water quality studies were carried out with respect to surface and ground water. The various physico- chemical and bacteriological parameters were analysed. It was observed that the physico-chemical parameters of surface and ground water lie within the standards stipulated for Indian subcontinent except for heavy metals which exceed the limits in ground water samples. Bacteriological analysis of sea water and ground water indicate that they are contaminated with faecal matters. Further, the ground water can be used for drinking purposes only after adequate treatment. 相似文献
406.
The Impact of NTFP Sales on Rural Households’ Cash Income in India’s Dry Deciduous Forest 总被引:1,自引:1,他引:1
In recent years, researchers and policy makers have recognized that nontimber forest products (NTFPs) extracted from forests by rural people can make a significant contribution to their well-being and to the local economy. This study presents and discusses data that describe the contribution of NTFPs to cash income in the dry deciduous forests of Orissa and Jharkhand, India. In its focus on cash income, this study sheds light on how the sale of NTFPs and products that use NTFPs as inputs contribute to the rural economy. From analysis of a unique data set that was collected over the course of a year, the study finds that the contribution of NTFPs to cash income varies across ecological settings, seasons, income level, and caste. Such variation should inform where and when to apply NTFP forest access and management policies. 相似文献
407.
Peng Y Jiang G Liu M Niu S Yu S Biswas DK Zhang Q Shi X Yang Q 《Environmental management》2005,35(4):453-460
Desertification directly threatens more than 250 million people and one third of the earths land surface. Although it is well known that desertification could be reversed in most cases if the intensity of land use were reduced, there have been no studies on how to achieve this reversed desertification on a large scale. We conducted a case study in Hunshandak Sandland of North China, exploring how creation of a nature reserve might aid restoration of a degraded ecosystem. Experimental data indicated that desertified regions, if designated as a nature reserve, could be restored with conservation of biodiversity. The buffer zones in moderately desertified lands could serve as a base for forage production and/or ecotourism industry. The construction of ecologically designed towns (ecotowns) in transition zones could accommodate migrants moved from core zones so as to develop stock production, related industry, and ecotourism, enabling both economic and environmental development. Up to now, 5778 local inhabitants in the core zones of Zhenglan Banner (county) in the Hunshandak Sandland have been moved out of the severely degraded areas with the financial assistance of the central government. Those people have been moved into three eco-towns of the Banner with an objective of greatly enhancing the economic and social status while restoring the degraded sandlands. 相似文献
408.
Hebbsale Mallappa Vinaya Kumar Shivamurthy M. 《Environment, Development and Sustainability》2021,23(8):11766-11791
Environment, Development and Sustainability - Time and again, climate change is a global phenomenon; intrinsically affects people and the environment more at the local and the global level when... 相似文献
409.
Alam Absar Kumar Jeetendra Sarkar Uttam Kumar Jha Dharm Nath Srivastava Saket Kumar Kumar Vijay Das Basanta Kumar 《Environment, Development and Sustainability》2021,23(9):13221-13241
Environment, Development and Sustainability - The present study evaluated the effectiveness of stocking the Gangetic carps, viz. Labeo catla, Labeo rohita, and Cirrhinus mrigala, in a large... 相似文献
410.
Gautam Sneha Samuel Cyril Gautam Alok Sagar Kumar Sanjeev 《Environment, Development and Sustainability》2021,23(11):16632-16645
Environment, Development and Sustainability - The present study aims to highlight the contrast relationship between COVID-19 (Coronavirus Disease-2019) infections and air pollutants for the Indian... 相似文献