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131.
Eberhart-Phillips D Haeussler PJ Freymueller JT Frankel AD Rubin CM Craw P Ratchkovski NA Anderson G Carver GA Crone AJ Dawson TE Fletcher H Hansen R Harp EL Harris RA Hill DP Hreinsdóttir S Jibson RW Jones LM Kayen R Keefer DK Larsen CF Moran SC Personius SF Plafker G Sherrod B Sieh K Sitar N Wallace WK 《Science (New York, N.Y.)》2003,300(5622):1113-1118
The MW (moment magnitude) 7.9 Denali fault earthquake on 3 November 2002 was associated with 340 kilometers of surface rupture and was the largest strike-slip earthquake in North America in almost 150 years. It illuminates earthquake mechanics and hazards of large strike-slip faults. It began with thrusting on the previously unrecognized Susitna Glacier fault, continued with right-slip on the Denali fault, then took a right step and continued with right-slip on the Totschunda fault. There is good correlation between geologically observed and geophysically inferred moment release. The earthquake produced unusually strong distal effects in the rupture propagation direction, including triggered seismicity. 相似文献
132.
133.
Variograms of Ancillary Data to Aid Sampling for Soil Surveys 总被引:2,自引:0,他引:2
To provide reliable estimates for mapping soil properties for precision agriculture requires intensive sampling and costly laboratory analyses. If the spatial structure of ancillary data, such as yield, digital information from aerial photographs, and soil electrical conductivity (EC) measurements, relates to that of soil properties they could be used to guide the sampling intensity for soil surveys. Variograms of permanent soil properties at two study sites on different parent materials were compared with each other and with those for ancillary data. The ranges of spatial dependence identified by the variograms of both sets of properties are of similar orders of magnitude for each study site. Maps of the ancillary data appear to show similar patterns of variation and these seem to relate to those of the permanent properties of the soil. Correlation analysis has confirmed these relations. Maps of kriged estimates from sub-sampled data and the original variograms showed that the main patterns of variation were preserved when a sampling interval of less than half the average variogram range of ancillary data was used. Digital data from aerial photographs for different years and EC appear to show a more consistent relation with the soil properties than does yield. Aerial photographs, in particular those of bare soil, seem to be the most useful ancillary data and they are often cheaper to obtain than yield and EC data. 相似文献
134.
Kerry L. Howell Rebecca Holt Inés Pulido Endrino Heather Stewart 《Biological conservation》2011,144(11):2656-2665
Internationally there is political momentum to establish networks of marine protected areas for the conservation of threatened species and habitats. Practical implementation of such networks requires an understanding of the distribution of these species and habitats. Predictive modelling provides a method by which continuous distribution maps can be produced from limited sample data. This method is particularly useful in the deep sea where a number of biological communities have been identified as vulnerable ‘habitats’, including Lophelia pertusa reefs. Recent modelling efforts have focused on predicting the distribution of this species. However the species is widely distributed where as reef habitat is not. This study uses Maxent predictive modelling to investigate whether the distribution of the species acts as a suitable proxy for the reef habitat. Models of both species and habitat distribution across Hatton Bank and George Bligh Bank are constructed using multibeam bathymetry, interpreted substrate and geomorphology layers, and derived layers of bathymetric position index (BPI), rugosity, slope and aspect. Species and reef presence records were obtained from video observations. For both models performance is fair to excellent assessed using AUC and additional threshold dependant metrics. 7.17% of the study area is predicted as highly suitable for the species presence while only 0.56% is suitable for reef presence, using the sensitivity–specificity sum maximisation approach to determine the appropriate threshold. Substrate is the most important variable in the both models followed by geomorphology in the RD model and fine scale BPI in the SD model. The difference in the distributions of reef and species suggest that mapping efforts should focus on the habitat rather than the species at fine (100 m) scales. 相似文献
135.
Janet Cumming Darryl Hawker Heather Chapman Kerry Nugent 《Water, air, and soil pollution》2011,216(1-4):441-450
Polymeric quaternary ammonium salts or polyquaterniums used in cosmetics have been categorised as chemicals of concern in wastewater treatment plant (WWTP) effluent largely on the basis of emerging evidence of toxicity to aquatic organisms. However, little is known of their environmental fate and behaviour due to analytical difficulties with sample matrices. Their properties of negligible volatilisation and biotransformation enable the common fugacity-based model for WWTPs to be simplified to an equifugacity one where a compound has the same fugacity regardless of phase or position in the plant??s process train. To gain an appreciation of their fate, this approach is used to calculate removal efficiencies in WWTPs. These can be determined without calculating phase-specific fugacity capacity constants. To predict effluent concentrations however, an aquivalence approach is necessary because of the lack of volatility of these compounds. Using previously measured biosolids/water distribution coefficients for common polyquaterniums found in cosmetics and flow rate data from a local municipal WWTP in South East Queensland, Australia, the removal efficiencies of the polyquaterniums of interest are predicted to be only 25% or less, meaning relatively little attenuation in the WWTP. A Monte Carlo simulation shows a roughly normal distribution in the model output of polyquaternium removal efficiency, with a mean and mode of approximately 26%. A sensitivity analysis confirms that the model output is most sensitive to the magnitude of the biosolids/water distribution coefficient compound and shows WWTP data such as biosolids removal efficiency have only a relatively small effect. 相似文献
136.
Heuter K 《Clinical Techniques in Small Animal Practice》2004,19(1):32-42
In veterinary patients, postgastric feeding is indicated for uncontrollable gastric vomiting, gastroparesis, biliary tract disease, pancreatitis, and for patients at increased risk for aspirating secondary to decreased mentation, prolonged recumbency, or an unprotected airway. Postgastric feeding may be implemented via the placement of a jejunal feeding tube. These tubes can be placed surgically (jejunostomy tubes) or with fluoroscopic or endoscopic guidance. This article will focus on methods of jejunal feeding-tube placement, advantages and disadvantages of the methods described, and complications associated with jejunal feeding. 相似文献
137.
Soltani-Gerdefaramarzi Somayeh Taghizadeh-Mehrjardi Ruhollah Kerry Ruth Shirmardi Mostafa 《Paddy and Water Environment》2021,19(4):585-594
Paddy and Water Environment - Drainage is a profitable water management operation in waterlogged soils, particularly in hot, arid environments where waterlogging is caused by irrigation and salts... 相似文献
138.
The principal neutral carbohydrate of three samples of echidna milk was identified as a trisaccharide, fucosyllactose. That of a sample of platypus milk was a tetrasaccharide, difucosyllactose. Free lactose was found in small amounts only. The milk carbohydrate of monotremes is distinguished from that of both marsupials and placental mammals by its high fucose content. 相似文献
139.
Sir:- Benzimidazole (Bz) resistant Nematodirus spathiger were first recorded in New Zealand in 1983.(2) 相似文献
140.
Kerry Chalmers 《New Zealand veterinary journal》2013,61(10):266-269
Oxfendazole (5 mg/kg) was tested against natural infections of nematodes and cestodes in sheep in three experiments. It was 100% effective against all stages of Ostertagia sp., Nematodirus spathiger, Oesophagostomum venulosum, Chabertia ovina, Moniezia expansa, immature 5th stage and adult Cooperia curticei and 4th stage Trichostrongylus sp. Efficacy was 99%–100% against immature 5th stage and adult Trichostrongylus sp., 67.8%and 91.6% against adult Strongyloides sp., 80.7%and 89.5% against immature 5th stage Trichuris ovis and 74% and 79% against Trichuris ovis. 相似文献