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71.
72.
Poly(ethylene terephthalate) and poly(acrylonitrile) fabrics are the most produced synthetic fabrics in the world. Their production and usage increase at medical textile. There is no functional group in their structure for enzyme immobilization. Hence, they are not inclined to react. However, functional groups could be added to their structure using graft polymerization. In this study, methacrylic acid was graft polymerized to poly(ethylene terephthalate) and poly(acylonitrile) fabrics. Characterization of modified fabrics was carried out and thrombin was immobilized to poly(methacrylic acid) graft polymerized poly(ethylene terephthalate) and poly(acylonitrile) fabrics using 1-Ethyl-3-(3-dimetylaminopropyl)-carbodiimide. Optimization studies were also performed for the immobilization of thrombin. Thrombin immobilized poly(methacrylic acid) graft polymerized poly(ethylene terephtalate) and poly(acrylonitrile) fabrics were reduced recalcification time 30 % and 25 %, respectively. It is the first time, an enzyme was immobilized to fabric and its in vitro applications were performed. Thrombin has not been immobilized to synthetic fabric, yet.  相似文献   
73.
The objective of this study was to improve the ability to model the air quality impacts of biomass burning on the surrounding environment. The focus is on prescribed burning emissions from a military reservation, Fort Benning in Georgia, and their impact on local and regional air quality. The approach taken in this study is to utilize two new techniques recently developed: (1) adaptive grid modeling and (2) direct sensitivity analysis. An advanced air quality model was equipped with these techniques, and regional-scale air quality simulations were conducted. Grid adaptation reduces the grid sizes in areas that have rapid changes in concentration gradients; consequently, the results are much more accurate than those of traditional static grid models. Direct sensitivity analysis calculates the rate of change of concentrations with respect to emissions. The adaptive grid simulation estimated large variations in O3 concentrations within 4?×?4-km2 cells for which the static grid estimates a single average concentration. The differences between adaptive average and static grid values of O3 sensitivities were more pronounced. The sensitivity of O3 to fire is difficult to estimate using the brute-force method with coarse scale (4?×?4 km2) static grid models.  相似文献   
74.
Water, Air, & Soil Pollution - The present paper deals with an extensive review of literature concerning the platinum group elements (PGEs), and their impact on the environment. The increased...  相似文献   
75.
The levels of susceptibility of populations of the European red mite Panonychus ulmi (Koch) (Acarina: Tetranychidae) collected from apple orchards in the Bursa region of Turkey to the insecticides chlorpyrifos and lambda-cyhalothrin, were determined by a petri leaf disk—Potter spray tower method. When compared with the susceptible population, resistance ratios at the LC50 level ranged from 6.0- to 35.6-fold, and from 0.7- to 5.7-fold for chlorpyrifos and lambda-cyhalothrin, respectively. Kinetic parameters of general esterase activity with α-naphthyl acetate as substrate indicated that an increased activity was present in the resistant populations compared with the susceptible populations. In these strains, 1.5- and 2.2-fold higher Glutathione S-transferase (GST) activity was also detected with the substrate 1-chloro-2,4-dinitrobenzene. General esterase activity gel profiles of these populations were studied by native polyacrylamide gel electrophoresis, but no relationship between resistance ratios and band patterns was detected. The results of this study document a decreased efficacy of chlorpyrifos and lambda-cyhalothrin in field populations of P. ulmi in Turkey, possibly linked to altered activities of esterases and GST.  相似文献   
76.
The functional response types and parameters of 3rd and 4th instar larvae, and adult females and males of a coccinellid predator, Adalia fasciatopunctata revelierei (Mulsant) (Col.: Coccinellidae), were evaluated at five different densities of Callaphis juglandis (Goeze) (Hemiptera: Aphididae) in order to understand their role for the aphid’s biological control. Experiments were carried out in petri dishes at 25 ± 1°C, 60 ± 10% r.h. and 16L:8D photoperiod in a controlled temperature room. All tested stages exhibited a Type II response determined by a logistic regression model. The attack rate (α) and handling time (T h ) coefficients of a Type II response were estimated by fitting a “random-predator” equation to the data. Although the estimates of α for all stages of A. fasciatopunctata revelierei tested were similar, the longest T h was obtained for 3rd instar larva because of the lower consumption rate at densities above 40 prey/day. Results indicated that the adult female has the highest predation of C. juglandis followed by 4th instar larvae, adult males and 3rd instar larvae. However, further field-based studies are needed to draw firm conclusions.  相似文献   
77.
A virus, mechanically transmitted fromLilium longiflorum toChenopodium spp., was identified in morphological, serological and ultrastructural studies as tulip breaking virus (TBV). Data presented indicate that the isolate differs from other TBV strains in host range and ultrastructural pathology.  相似文献   
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79.
Yatagan thermal power plant consumes annually 5.4 million tons of coal and the annual production capacity of the plant is 3.78 billion KWh. The thermal power plant uses 15 000 tons of coal and discharges 5000 tons of fly and bottom ash daily to the disposal site. The waste is dumped using conveyer belts and pipes into a dam founded on metamorphic rocks. However, as the waste hills formed, the water level reached the karstic marbles that over lay schist. Water leaches through dried waste hills and karstic marbles, ultimately adversely affecting the quality of ground and surface waters. The concentrations of major and minor ions were determined on water samples taken at 2 points in the dam, 5 points in surface water and at 21 points in groundwater located in the vicinity of the waste disposal site, total of 28 samples, for three years. The chemical analyses revealed that the concentrations of Ca2+, Cd2+, Pb2+, Sb2+ and SO4 2- in some samples exceed the Turkish Drinking Water, the U.S. EPA and WHO limits. Isotope analyses were carried out to determine the origins of waters, which showedthat contamination is taking place in the vicinity of the waste disposal site.  相似文献   
80.
Yatagan Thermal Power Plant consumes low-quality ligniteproduced from the Yatagan Basin, located in the western part ofthe Aegean region nearby Mugla City. The basin is aligned in anorthwest-southeast direction. The dominant wind direction isalso northwest-southeast, which controls the boundary of thewaste at the disposal site. In this study, the concentration of30 volatile elements was analyzed in coal, bottom ash, fly ashand background soil. The study area was divided into grids. The size of the grids was 1 km2 for the background soiland 50–100 m for the ash in the vicinity of the wastedisposal site. 15 fly and bottom ash, six coal and nine-background soil samples were analyzed according to a sequential technique using ICP-AES. The results reveal that heavy metal concentrations in the coal are below the world averages for coal whereas those of bottom ash and fly ash arewithin the world averages for the respective ashes, indicatingheavy metal enrichment. It is recommended that extra care shouldbe taken to prevent subsurface contamination in the study area.  相似文献   
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