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51.
Dry‐grind corn processing facilities produce ethanol, carbon dioxide, and distillers dried grains with solubles (DDGS). To produce DDGS, dry‐grind corn processors concentrate thin stillage in multieffect evaporators. Concentration of thin stillage uses large amounts of energy, and efficient operation is important for long‐term economic stability of the industry. Little data are available on fouling of evaporators during thin stillage concentration. We evaluated how thin stillage pH and acid type used during pH adjustment affected fouling as measured by induction period, fouling rate, and deposit composition. Using an annular fouling apparatus, fouling tests were conducted at pH 3.5, 4.0, and 4.5. In a second experiment, we used two types of acid, HCl or H2SO4, to adjust thin stillage to pH 3.5. Induction periods were shorter at pH 3.5 than at pH 4.0 or 4.5. As pH increased, fouling deposit protein decreased and ash increased. Concentrations of most elements, including P, Ca, Mg, Mn, and K, increased with an increase in pH. Phosphorus was the most abundant mineral element in fouling deposits. Induction periods were similar for the two acids. Thin stillage pH has an influence on deposit concentration, fouling rate, and induction period.  相似文献   
52.
1. This study compared the effects of electrical stunning delivered using high and low frequency waveforms on carcase and meat quality of turkeys processed under commercial conditions. 2. The use of a high frequency waveform (1400 Hz) resulted in a faster bleedout and an improvement in carcase quality associated with a substantial reduction in haemorrhagic downgrading conditions. 3. Frequency of the applied waveform influenced breast muscle pH and colour although the magnitude of the differences was considered to be of minimal significance in influencing consumer perception.  相似文献   
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This article has described many of the advantages of using a sequential multichannel autoanalyzer to obtain a biochemical profile on animal blood specimens and how this profile can be used in assessing the patients biochemical status. Precautions concerning the collection of blood samples to avoid spurious results have been emphasized. Hemolysis should, in particular, be avoided. Ideally, plasma should be separated from cells shortly after collection and refrigerated. If this is not possible, storage of whole blood under refrigeration (4 degrees C.) is permissible for a short period. In these cases minor changes in blood glucose, total CO2, and calcium may be expected. Also presented are some of the statistical calculations and manipulations that are possible utilizing a data bank containing the data from the SMA 12/60. This information is being used to update much of our knowledge of veterinary clinical pathology.  相似文献   
56.
P. W. Wilkins 《Euphytica》1991,52(3):201-214
Summary Perennial ryegrass has become the most widely sown perennial forage grass in temperate regions due to its combination of high digestibility and tolerance of grazing. The primary objectives in breeding for agricultural use are to improve total and seasonal dry matter production over a range of fertiliser inputs, digestibility, persistency, freezing tolerance and drought or heat tolerance. Adequate seed production and resistance to a wide range of diseases and pests is also necessary. Improvements in productivity and persistency so far have been achieved mainly by hybridisation and recurrent selection using the polycross method and by the use of polyploidy. Further improvements in freezing tolerance, drought and heat tolerance and, for some localities, resistance to pests and snow moulds are required to extend the geographic range of the species. Modern cultivars show little improvement in leaf or stem digestibility but a high magnesium variety is now available. Perennial ryegrass breeding is at an early stage and prospects for further progress appear good.  相似文献   
57.
Two-tooth ewes (n=48) were immunized pre-tupping with a live Toxoplasma gondii vaccine. At midpregnancy these ewes were challenged intravenously with 1 x 105 live T. gondii tachyzoites. The strain of T. gondii used for vaccination was an incomplete strain that did not produce oocysts. It was derived by continuous twice weekly passage in mice. The lambing percentage for ewes immunized with the live vaccine was significantly higher (P<0.001 normal score) than non-vaccinated control ewes. However, vaccination did not prevent foetal or placental infection. The serological response to vaccination and challenge was measured by both the Dye test and the Indirect Haemagglutination test. No significant relationship between titre of antibody and protection in the vaccinated ewes was observed.  相似文献   
58.
Understanding the behavior of sulfur (S) in the soil‐plant system is important for crop production, for predicting the movement of the radioisotope 35S in the environment, and for investigating the role of S in plant metabolism of xenobiotics. A database of relative mean S concentrations in 121 species of flowering plants was constructed using a Residual Maximum Likelihood (REML) procedure with new experimental data for 76 species and literature data for 57 species, there being 12 species in common. The relative mean S concentrations in plant species were normally distributed and their range greater than previously reported for S concentrations between plant species. There was a significant phylogenetic effect on S concentrations when they were analyzed using a nested ANOVA coded with a recent phylogeny of flowering plants. About 36% of the variance between species was associated with the rank of Order and above. At the rank of Order, S concentrations were Brassicales > Malphigiales > Lamiales > Rosales > Caryophyllales > Malvales > Poales > Fabales > Fagales > Asterales. Experiments to quantify intervarietal differences within Beta vulgaris, Triticum aestivum, and Cicer arietinum revealed that these reached a maximum in B. vulgaris at about 20% of those found at the species level and above. A comparison of relative mean S concentrations with previously reported relative mean concentrations for heavy metals suggested correlations between S and cadmium (Cd), and S and zinc (Zn). The frequency distributions and phylogenetic effects reported here are useful to understanding soil‐plant transfer of stable and radioactive S isotopes in agricultural and natural ecosystems and might aid investigations of plant response to xenobiotics.  相似文献   
59.
An organosolv (Alcell) lignin was fractionated with both sequential solvent-extraction and solvent-mixture precipitation using various organic solvent systems. The resulting fractionated lignins were used to prepare matrix granules with bromacil as a model compound using a melt process. The release rates of bromacil in vitro from the granular matrix system were influenced by both the lignin used as carrier and the solution fractionation. The variations in release rates were related to the high proportion of low-molecular-weight fraction and its associated water-soluble lignin in the fractionated lignins. Fickian diffusion was a predominant factor in controlling the release of bromacil from the matrix granules based on the low-molecular-weight fraction (L(fr1)). For the matrix granules based on the other fractionated lignins, the release of bromacil was of super-case II transport. The fine structure of the matrix granules before and after release was also studied. An unique release pattern of bromacil was observed for the matrix granules based on the low-molecular-weight fraction (L(fr1)), showing a fast release followed by zero-order release, which was a result of remarkable changes in the structure of the matrix granules during the course of release.  相似文献   
60.
Summary Six diploid perennial ryegrass populations, two diploid F1 hybrid families and the autotetraploid cv. Tove were grown in a glasshouse and the mean length and mean width of epidermal cells on the abaxial leaf surface of young fully expanded leaves compared. The diploids varied in cell length by 26%, in cell width by 9% and in length: width ratio by 39%. The cells of cv. Tove were 25% longer and 12% wider than those of the highest ranking diploid and the length: width ratio 9% higher. The DNA contents per telophase root-tip cell nucleus of a large-celled and a small-celled diploid population were similar, suggesting that the variation in epidermal cell size among diploids was due to the action of specific genes and not to differences in genome size. The mean epidermal cell dimensions of four of the above populations growing as plots in a field trial employing three levels of fertiliser nitrogen and four harvesting frequencies were measured on three occasions. Varietal ranking in cell dimensions was consistent over the different managements and dates, and agreed well with the glasshouse results. The results indicate that measurements of leaf epidermal cell length and width can be useful aids both in breeding for herbage yield and in distinguishing varieties with similar flowering dates.  相似文献   
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