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101.
Vinyl acetate (VAc) monomer of different percentage was grafted onto the recycled polyethylene terephthalate (r-PET) films using gamma irradiation. The properties of these modified films were characterized by Fourier transform infrared spectroscopy (FTIR), mechanical properties testing (Tensile strength, Elongation at break), dynamic mechanical analysis (DMA) and thermo-gravimetric analysis (TGA). The Tensile Strength (TS) of the modified PET film increased by 132.25?% to the highest value of 50.12 MPa at 15% VAc monomer concentration at 3 kGy gamma dose, while the elongation at break (EB) decreased by 31.83?%. FTIR was used to investigate the molecular interaction of the modified films. TGA revealed that curve of the modified PET film shifted toward higher temperature region by 95?°C, which is very close to that of PET film made from virgin flakes. The results indicate that modified PET films of better mechanical and thermal properties were successfully prepared using VAc monomer grafting by gamma irradiation technique.  相似文献   
102.
Environmental Chemistry Letters - Research has recently focused on combinational therapy using nanocarriers to overcome the obstacles associated with conventional therapy of lung cancer. The...  相似文献   
103.
Journal of Material Cycles and Waste Management - The relationship between local structure and visible-light-activated photocatalytic ability of glass–ceramics prepared from Municipal Solid...  相似文献   
104.
Environmental Science and Pollution Research - Substantial discharge of hazardous substances, especially dyes and heavy metal ions to the environment, has become a global concern due to...  相似文献   
105.
Journal of Polymers and the Environment - In the present investigation, the influence of coir micro-particles and titanium carbide (TiC) nanofillers on mechanical characteristics and thermal...  相似文献   
106.
Several hypotheses have been suggested to explain the evolution and maintenance of helping behavior in cooperatively breeding birds, one of which we investigated in the red-cockaded woodpecker (Picoides borealis). Helping may provide a learning experience that improves reproductive success once the helper becomes a breeder. We used data collected from a population of red-cockaded woodpeckers in the Sandhills of North Carolina to compare the reproductive success of 2-year-old breeders that were helpers at age 1 (helping experience) to those that were floaters or solitary males at age 1 (no helping experience). Reproductive success of the two groups was similar, indicating that helping provides no experience useful in reproduction. We reject the learning experience hypothesis as an explanation for the maintenance of helping behavior in red-cockaded woodpeckers. Received: 29 July 1996 / Accepted after revision: 27 April 1997  相似文献   
107.
Role of probiotics on the environment of shrimp pond   总被引:1,自引:0,他引:1  
Recent disease outbreak in shrimp farming caused mainly by bacteria, virus, fungi or a combination of these etiologic agents is attributed to disturbance in the environment of pond. To combat this, different antibiotics and chemicals are being used which are reported to be not environment friendly. Of late, a new and unique biotechnological product called "Probiotics " is being used widely by all the shrimp farmers worldwide, which is found to be more effective and environmentally safe also. In the present study 2 probiotics were used in a small 0.7 ha shrimp farm near Pattukottai in Tamil Nadu State for one culture period for the management of pond environment and also the gut ecology of Penaeus monodon. The environmental parameters analysed were within the acceptable limits. It was evident from the results that the production was better in the experimental pond where the probiotics were used. The biological parameters such as the average body weight, FCR and total harvest achieved were better in the experimental pond than the control pond, all due to congenial environment, which obtained in the former mainly due to the use of probiotics.  相似文献   
108.
The root growth response to air pollution in populations of Anagallis arvensis growing about 0.5, 2, 6, 12 and 20 km leeward from a power plant complex varied with the level of pollution, age of the stand and meteorological conditions. The roots were more affected by the pollutants at a young stage and the loss in net primary productivity was proportional to the pollution level. The populations up to 2 km from the source of pollution completed their life cycle quickly. The coal consumption rate at the power plant, relative humidity, wind direction and other environmental factors were found to influence the degree of growth response to air pollution.  相似文献   
109.
The use of two natural sorbents, kapok and cattail fibers, were investigated for polycyclic aromatic hydrocarbon (PAH) removal from water. Naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, and fluoranthene were the PAHs studied. For comparative purposes, a commercial polyester fiber sorbent was included in the investigation. The PAH sorption and retention capabilities of the three fibers were determined through batch and continuous-flow experiments under non-competitive and competitive conditions. In the batch experiments, cattail fiber was the most effective sorbent. Kapok fiber provided the lowest PAH retention, while cattail fiber had slightly less PAH retention than polyester fiber. When two PAHs were present in the same system, a competitive effect on the much less hydrophobic PAH was observed. Similar results were obtained in the column experiments, except that polyester fiber performed much poorer on naphthalene. Cattail fiber is a promising sorbent for treating PAH-contaminated water, such as urban runoff.  相似文献   
110.
Interacting effects of ozone at 0.05, 0.1 and 0.2 ppm and powdery mildew infection were studied with respect to the growth, flowering and fruit-setting of bottle gourd, and ozone injury, fungal colonization, conidia size and germination. Intermittent exposure in closed-top chambers to ozone at 0.1 or 0.2 ppm, and infection by Sphaerotheca fulginea, each caused significant suppressions of plant growth, flowering and fruit-setting. Fungal colonization was increased by exposures to 0.05 ppm ozone, but decreased by 0.2 ppm ozone. Less browning and necrosis (symptoms of ozone phytotoxicity) appeared on the leaves of mildew-inoculated plants exposed to ozone at 0.1 and 0.2 ppm. Conidia collected from plants exposed to 0.1 and 0.2 ppm were smaller, contained fewer fibrosin bodies and showed poor germination in-vitro. Fumigations with ozone at 0.05 ppm increased the germination of conidia collected from the exposed plants or of the conidia directly exposed to ozone on glass slides in microgas exposure cabinets. Distortion and wall rupturing of the conidia were induced by exposure to ozone at 0.2 ppm for 12 h. Ozone at 0.05 ppm and S. fuliginea jointly suppressed the root and shoot growth of bottle gourd significantly more than the sum of individual effects (synergistic interaction). The fungus infection partially protected the plants from injury by ozone at 0.2 ppm, and exposure to ozone at 0.2 ppm inhibited fungal development. Antagonistic reductions of damage to bottle gourd growth by simultaneous mildew infection and ozone at 0.2 ppm were observed. The study revealed that powdery mildew infection may become severe on bottle gourd grown in areas polluted with mild level of ozone (0.05 ppm) whereas, at 0.1 ppm O3 or more, the disease will be suppressed.  相似文献   
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