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511.
512.
Dietary and industrial uses of cassava (Manihot esculenta Crantz) are threatened by the known presence of cyanide in the crop and its products. The toxic HCN content of cassava may be altered by some intrinsic and extrinsic factors in and around the plant, but the extent of any shifts in this regard due to stress conditions created by cassava green spider mites (CGM) Mononychellus tanajoa and mealybugs (CM) (Phenacoccus manihoti, now spreading epiphytotically in almost all cassava-growing areas in Africa, is unknown. In this study, we report variations in the total HCN content of leaf, stem and root tissues of six cassava clones differentially infested by these pests. 相似文献
513.
Shradha Panwar Devendra K. Agrawal Khilendra S. Kanwal Vertika Sharma Mahendra S. Lodhi 《Journal of Environmental Planning and Management》2010,53(7):907-923
This study provides an overview of the impacts of a proposed hydroelectric power project in the Western Himalayan region in India, using a primary database on floristic diversity and vegetation analysis. The remote sensing data revealed that in the submergence zone only mixed deciduous forest that occupies 807.5 ha area and has a wood biomass volume of 4,027,503 m3 is likely to be lost due to impoundment. A total of 165 plant species found in the submergence zone also occur in the influence and free draining catchment area of the project. In the influence zone of the project area only one tree species (Acer oblongum) is found under conservation threat category, which is also present in the free draining catchment of the project. The project affected population (6716 people) residing in the submergence and influence zone depend upon the surrounding forests for fuel wood, fodder, wild edibles etc., and most likely they will settle in the nearby areas, thus mounting more pressure on residual forests of the influence zone for various forest products. Further, from the vegetation analysis it is evident that several tree species (e.g. Lannea coromandelica, Terminalia alata, T. bellerica etc.), may face more pressure from exploitation as they provide a number of useful products and are represented in lower numbers in the forests of the project area. To compensate for the loss of various goods and services provided by the forests falling in the submergence zone and to offset the increased pressure of the project affected families on the forests of influence zone, a biodiversity management plan is suggested incorporating socio-economic considerations. 相似文献
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515.
Coal combustion in the power sector gives rise to the emission of primary and secondary particulate pollutants. Since the emission of pollutants depends on coal quality and combustion technology, and given that transport, transformation and deposition of contaminants depend on regional climatic conditions, specific studies for the power stations is needed to evaluate their environmental impacts. Monitoring of ambient respirable suspended particulate matter (RSPM) and suspended particulate matter (SPM) levels around a large coal-fired power station in India was carried out. The specific objectives were the determination of spatial and seasonal variability in RSPM and SPM levels, and their relationship with meteorological parameters such as wind velocity and relative humidity. The results have shown a marked seasonal trend and spatial variability in RSPM and SPM levels in the study area. Higher concentrations of ambient RSPM and SPM were found in downwind monitoring stations compared to upwind direction. Ratios of RSPM to SPM and correlation coefficient values between RSPM and SPM along with meteorological parameters were also worked out. Relative humidity and wind velocity have shown an inverse relation with particulate deposition pattern. 相似文献
516.
In this review a brief introduction to thiram (tetramethylthiuram disulfide; TMTD) pesticide has been given along with other applications. All the important methods available are systematically arranged and are listed under various techniques. Some of these methods have been applied for the determination of thiram in commercial formulations, synthetic mixtures in grains, vegetables and fruits. A comparison of different methods is the salient feature of this review. 相似文献
517.
This paper reports study of day-to-day instability in the locomotor activity rhythm of the nocturnal field mouse Mus booduga. The free-running period (τ) of this rhythm was estimated in constant darkness in n=347 adult male mice. The "onset" and "offset" of locomotor activity rhythm were used as phase markers of the circadian clock.
The precision of the onset of locomotor activity was observed to be a non-linear function of τ, with maximal precision at
τ close to 24 h. The precision of the offset of locomotor activity was found to increase with increasing τ. These results
suggest that the homeostasis of τ is tighter when τ is close to 24 h.
Received: 5 May 1998 / Accepted: 11 February 1999 相似文献
518.
Vikrant Jaryan Sanjay Kr. Uniyal Gopichand R. D. Singh Brij Lal Amit Kumar Varun Sharma 《The Environmentalist》2010,30(2):101-110
Recognizing the importance of sacred groves in biodiversity conservation and management, and the recent threats to them, the
present study was conducted in Shivbari sacred grove of Himachal Pradesh. The study aimed at documenting the floral wealth
of Shivbari and promoting plantation of indigenous species in participation with local people. For this, systematic field
surveys in different seasons were conducted in Shivbari from April 2005 to November 2009, and liaison was maintained with
the local community and temple management authority for gaining insight into the history and problems of Shivbari and initiating
plantation activities. A total of 69 flowering plant species were identified inside the grove, which include 14 trees, 9 shrubs,
3 lianas and 43 herbs. This represents almost 2% of the total flowering plant species occurring in the state of Himachal Pradesh.
Mallotus philippensis followed by Putranjiva roxburghii was the most dominant tree species. Adhatoda
zeylanica was the most common shrub species, while Achyranthes aspera was the most common herb species. The grove harbours 23 plants species that are in high demand in the market, and at the
same time also influences the microclimate of the area. The temperature inside the grove was significantly lower than the
temperature outside the grove. The recent changes in socio-economic status of the local people and a shift towards market-oriented
economy have threatened the survival of Shivbari. However, the deeply held beliefs of the pilgrims, local people and priest
offer a ray of hope. During the course of the study, 3,000 plants were planted inside the grove out of which 60% have survived. 相似文献
519.
520.