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51.
《The Journal of Applied Poultry Research》2004,13(4):680-683
Ether extract composition of poultry by-product meal (PBM) varies among feed-grade and pet food-grade sources. Because feed-grade PBM contains a wider variety of processing residues than pet food-grade PBM, it is presumed to be of lower fat quality (i.e., stability). This potential difference in fat quality, or stability, between PBM sources can be accentuated by high environmental temperatures. A total of 46 PBM samples (25 feed-grade and 21 pet food-grade) were collected from commercial feed mills located in the southeastern US within 60-d intervals during the winter and summer months.For samples from winter collection, feed-grade PBM had lower fat stability than pet food-grade PBM. Conversely, pet food-grade PBM samples received in the summer were characterized as having poor stability, and the amount of analyzed residual antioxidant concentration in pet food-grade PBM was half that found in the feed-grade PBM samples. Seasonal effects appeared to be related to the extent of fat oxidation. In general, samples obtained in the summer had poor stability when compared with those collected during the winter, regardless of source. These results confirmed that fat in PBM requires an adequate amount of antioxidant protection, even when meals are derived from prime offal components. 相似文献
52.
《The Journal of Applied Poultry Research》2004,13(3):426-432
Accurate sampling of broiler litter for nutrient analysis is critical for nutrient management and land application. Litter can be applied to agricultural land either fresh or after composting. If applied fresh, sampling should be done before house clean out so that the nutrient analysis results are readily available prior to land application. There are 2 methods that are suitable for obtaining representative litter samples in poultry houses, the trench and the point methods. This study was designed to investigate the effect of sampling methodology on the resultant nutrient content of broiler litter and how nutrient concentrations in broiler litter differ between brooding and nonbrooding areas in the production unit. The sampling methods gave similar results for litter pH, moisture content (MC), total Kjeldahl nitrogen (TKN), and total phosphorus (TP), thus indicating that the random walk method can be used to easily collect representative samples instead of the more time- and labor-intensive trench method for nutrient management purposes. The total ammoniacal nitrogen (TAN) content was significantly higher for the trench method, however, TAN accounted for less than 15% of the litter TKN. Litter MC, TAN, and TP varied significantly in each of the nonbrooding areas and the brooding area. Moisture content was 28.5, 32.0, and 28.0% for the brooding, north, and south nonbrooding areas, respectively. Litter TKN levels were 37.4, 24.9, and 20.5 g/kg for the brooding, north, and south nonbrooding areas, respectively. The TAN concentrations were higher at the north nonbrooding areas. The TP concentrations were 10.4, 8.8, and 8.5 g/kg for north nonbrooding area, brooding area, and south nonbrooding area, respectively. Our results indicate the need for sampling litter in both brooding and nonbrooding areas in broiler houses for the determination of average litter nutrient and MC. 相似文献
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54.
结合广东省畜禽饲养量 ,采用各类畜禽粪便及其污染物的排泄系数 ,估算出畜禽粪便污染物排放总量、污染物流失量。研究发现 :畜禽养殖业的粪尿流失量是工业固体废弃物的 2 1倍 ;COD和NH3 -N的流失量分别是生活和工业废水的COD和NH3 -N排放量的 1 4倍和 1 7倍 ,畜禽粪便造成的环境污染是农村面源污染的主要原因。并提出采用综合防治的思路解决广东省畜禽养殖的污染问题 相似文献
55.
Ahmed A. M. Awad Atef A. A. Sweed 《Communications in Soil Science and Plant Analysis》2020,51(8):1101-1113
ABSTRACT The objective of this study was to study the influence of three organic manures, farm yard manure (FYM), poultry manure (PLM), and pigeon manure (PGM), on soil physical and chemical properties on tuber yield of Jerusalem artichoke in a newly reclaimed saline calcareous soil. A field experiment was conducted applying the three manures, alone and/or in different combinations. Soils were investigated at surface (0–30 cm) and subsurface (30–60 cm) layers before and after planting, and analyzed for physical and chemical properties. The results indicated that the application of 31.5 kg ha?1 of PLM+10.5 kg of PGM T7 recorded highest available nitrogen, zinc, copper, and moisture content at the surface layer. The same results were obtained for iron and manganese at both layers. While, applying 21.0 kg ha?1 FYM+21.0 kg ha?1 PLM T10 recorded the best treatment for pH, phosphorus, zinc, copper, moisture content, and saturation percentage at the subsurface layer. Applying 21.0 kg ha?1 PGM + 10.5 kg ha?1 FYM+10.5 kg ha?1 PLM T15 recorded the best treatment for organic matter content and bulk density at surface layer and reduced the electrical conductivity and inulin tuber content at both layers. On the other hand, calcium carbonate and sodium adsorption ratio were reduced in both layers by applying 21.0 kg ha?1 PLM+10.5 kg ha?1 FYM+10.5 kg ha?1 PGM T14. The best treatment for tuber nitrogen content and total yield was obtained with applying 42.0 kg ha?1 PLM T2 only and 31.5 kg ha?1 FYM+10.5 kg ha?1 PLM T4, respectively. 相似文献
56.
彭里 《中国生态农业学报》2006,14(2):19-22
简述了近年来国内外畜禽养殖环境污染现状及其危害、畜禽粪便环境污染治理研究进展。 相似文献
57.
《The Journal of Applied Poultry Research》2005,14(3):542-547
The effects of poultry by-product meal (PBPM) and feather meal (FM) incorporated separately and in combination in the diet on laying hen performance and egg characteristics during postpeak production were determined. Bovans White strain laying hens, 42 wk of age, were fed diets with 0% PBPM and FM, 5% FM, 5% PBPM, or 4% FM + 4% PBPM. Egg production, feed intake, and egg mass were not significantly affected by dietary treatments, whereas egg weight and feed conversion ratio (FCR) were significantly affected. Egg weights of hens receiving 4% FM + 4% PBPM were significantly lower than those fed the control diet, whereas those fed 5% FM or 5% PBPM were intermediate. FCR was significantly improved by the diets containing 5% FM or 5% PBPM compared with the diet containing 4% FM + 4% PBPM. Dietary PBPM decreased Haugh units, but FM did not. Egg breaking strength, shell weight, and weights of albumen and yolk were not affected by treatments. The results suggested that FM or PBPM could be incorporated up to 5% singly or up to 8% in combination in layer diets but with possible detrimental effects on Haugh units, egg weight, and FCR. 相似文献
58.
Critical drainage and nitrate leaching losses from manures applied to freely draining soils in Great Britain 总被引:1,自引:0,他引:1
Abstract. Pig slurry was applied by open-slot injection to experimental plots on a sandy loam site at ADAS Gleadthorpe, Nottinghamshire. Volume and distribution of over-winter drainage were adjusted through the use of rainfall exclusion covers or irrigation. The resultant slurry N leaching over the range of drainage values tested (up to 300 mm) could be satisfactorily described by curve-fitting, using a quadratic or exponential function. Initial simulations of slurry N leaching using the manure nitrogen decision support system manner (v. 3.0) compared poorly with the experimental data, predicting both earlier and greater amounts of nitrate leaching. However, the lack of fit could be explained by consideration of the likely ammonia emissions following slurry injection, the actual volumetric soil moisture capacity at the experimental site and the likely time delay for the nitrification of slurry N following application. Good agreement between modelled and observed data was achieved when these factors were taken into account. The manner model was used to simulate nitrate leaching beyond the range of drainage treatments tested in the experiments and the anticipated sigmoidal relationship between nitrate leaching and drainage was observed. The model was then used to study the effects of manure application timing and the likely impact on nitrate leaching, across the range of rainfall conditions found in Great Britain. Simulations for a range of manure types were undertaken, with manures applied at rates up to the limit of permitted N loading on freely draining sandy loams. Rainfall inputs for these simulations were based on long-term average climatic data. Results are presented for two contrasting manure types, cattle slurry and poultry manure, both of which are subject to controls in Nitrate Vulnerable Zones (NVZs) in Great Britain. 相似文献
59.
合理的布置城镇居民住宅区,推广和建设健康住宅,不仅有利于经济繁荣、保护环境,而且也达到了人与自然、人与人、以及人自身的健康和谐。 相似文献
60.