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11.
This study investigates the development of thermoset plastics from plant-based oils (e.g., linseed, soybean, cottonseed, oilseed radish, and peanut oils) using an optimal process of solvent-free epoxidation. The epoxidation of plant oils can be accomplished economically by reacting the double bonds of fatty-acids with hydrogen peroxide. During the solvent-free process catalyzed by the ion-exchange resin, we observed that the influence of several variables was important: the molar ratio of hydrogen peroxide to unsaturation, acetic acid to unsaturation, and temperature. The epoxidation of plant oils was determined from the liquid mixture and the composite matrix by thermal and spectroscopic analyses. Compounds with a higher double-bond (iodine) value showed higher oxirane oxygen percent and selectivity, and a higher hydroxyl value because of a greater possibility of attack by solutions causing side reactions. Lower iodine values indicated fewer epoxy groups and selectivity, and a lower hydroxyl value. Benzyl pyrazinium hexafluoroantimonate (BPH) yielded good thermal curing properties; as little as 1% added to the plastics produced light-weight composites. Epoxidized linseed oil promises the highest modulus and impact resistance due to the largest number of double bonds to contribute more epoxy groups and the large proportion of linolenic acids to produce epoxy groups rapidly.  相似文献   
12.
基于异速生长关系的棉籽蛋白质含量模拟模型   总被引:1,自引:1,他引:0  
基于不同熟性棉花品种的异地分期播种和施氮量试验,运用异速生长模型分析棉籽氮浓度与棉籽生物量间的关系,建立氮素的潜在增长模型,进而综合品种特性、主要气象条件(温度、太阳辐射)和栽培措施(施氮量)等因子,建立基于异速生长关系的棉籽蛋白质含量模拟模型。利用不同生态点品种、播期和施氮量的田间试验资料的检验结果表明:安阳、淮安和徐州试点模拟值与实测值的根均方差(RMSE)分别为2.2%、4.1%和2.3%。说明依据棉籽蛋白质含量与生物量间的异速生长关系模拟棉籽蛋白质形成切实可行,模型预测性好,广适性强。模型的不足在于其精确度受棉籽干物质累积模型和棉铃对位叶N浓度模型的影响较大。  相似文献   
13.
Composite flour blends containing wheat (W), fababean (F), cottonseed and sesame flours were formulated to provide the FAO/WHO/UNU protein requirements for the 2–5 year old child, and evaluated in pan and flat bread applications. Water absorption of composite flour doughs was up to 35% greater than the control but gluten strength and slurry viscosities were markedly reduced. Loaf volume and specific volume of pan breads prepared from composite flours were 25–60% less than that of the control bread but flat breads tolerated the protein supplements extremely well. The W/F flat bread, containing 27% of fababean flour, received acceptable taste, texture and colour scores and was only slightly inferior to the control in puffing and layer separation. Additions of cottonseed or sesame flours to the W/F blend failed to improve sensory properties of the flat breads.  相似文献   
14.
Cottonseed protein has the potential to increase the world's food supply while decreasing the incidence of malnutrition among the world's hungry. Nutritionally, cottonseed flour compares favorably to other animal and vegetable protein sources, as it is low in fat and contains a substantial amount of high biological value protein. Animal studies, as well as human research, using gossypol-free glandless cottonseed flour have shown that cottonseed protein promotes growth, increased weight gain, and a positive nitrogen balance. Cottonseed protein food products have been shown to be a healthy addition to the diets of children, college-age women, and the elderly. With its light color and bland flavor, cottonseed has many uses in the food processing arena. Baked goods, snack foods and candy, as well as pet and livestock feed are just a few successful products developed utilizing cottonseed protein.  相似文献   
15.
棉子壳菌糠的营养价值分析   总被引:1,自引:0,他引:1  
对不同收菇次数棉子壳菌糠的获得率和营养物质含量进行了分析。结果表明,随着收菇次数的增加,棉子壳菌糠的获得率减少;不同收菇次数对棉子壳菌糠的营养成分影响较大,以第三茬菇收获后菌糠的营养成分含量最好。  相似文献   
16.
影响棉籽饼有效赖氨酸含量因素的试验研究   总被引:2,自引:0,他引:2  
本试验模拟螺旋压榨榨油工艺,测定不同蒸炒或加热条件对棉籽饼中自由棉酚(FG)、还原糖(RS)、有效赖氨酸(A-Lys)含量的影响。对蒸炒前喷洒硫酸亚铁的作用也做了初步探讨。研究发现,加热强度、棉酚结合、还原糖含量与有效赖氨酸含量之间的相关系数分别为-0.9765(P<0.01)、-0.9515(P<0.01)、0.4395(P>0.05);蒸炒前添加FeSO4,按Fe∶FG摩尔比4.5∶1和9∶1时均极显著地(P<0.01)提高A-Lys含量,两剂量组间无差异(P>0.05);按4.5∶1添加FeSO4可提高A-Lys7.60%~37.77%,同时表明,FG含量显著降低。  相似文献   
17.
双孢蘑菇菌种基质改进的研究   总被引:2,自引:1,他引:1  
本文报导了用于双孢蘑菇菌种制种基质材料的研究。结果证明:平菇生产下脚料是替代棉籽壳制作蘑菇菌种的好材料,其菌种质量与棉籽壳菌种无差别,大大地降低了菌种生产成本。  相似文献   
18.
本文笔者分别按5∶1、4∶1、3∶1的比例在牛粪中加入豆粕、棉籽粕、菜籽粕进行发酵试验,以研究不同粕类对发酵牛粪中氮、磷、钾含量的影响。结果表明,加入豆粕与牛粪共同发酵后其质地最柔软,所得的氮、磷、钾含量最高,且牛粪与豆粕混合比为3∶1时所得有机肥的种子发芽率最高,表明用豆粕与牛粪发酵(3∶1)效果最好。  相似文献   
19.
通过对泡沫酸脱绒后的棉种残酸值与氨中和的研究和探讨,用回归分析法对残酸值和氨中和效果进行了预测,并经优化计算,得出最佳方案。  相似文献   
20.
Two experiments were carried out at Giza Agric. Res. St., Agric. Res. Centre, Ministry of Agric, Egypt, during 1981 and 1982 seasons on cotton cultivar Giza 75 ( Gossypium barbadense L.) to investigate the influence of nitrogen fertilization rates (72, 144 or 216 kg N/ha), phosphorus levels (36 or 72 kg P2O5/ha) and three growth regulators (IAA, IBA or NAA), each was applied to cotton plants at 10 ppm and sprayed three times (70, 85 and 100 days after sowing), on cotton seed, protein and oil yields and oil properties. A randomized complete block design, with four replications treatment combinations was used.
The combined analysis of the results of the two seasons revealed that, cottonseed, oil and protein yields/ha increased by raising N- and P-levels and under the application of growth regulators. Seed index increased by raising the added-N and the applied growth regulants. No detectable effect of P-levels was observed. The seed oil percentage decreased, while the protein percentage increased by raising N-rate. Application of growth regulators and high P-level increased the seed oil percentage, while the seed protein percentage was not affected. The seed oil properties, i.e. acidity, saponification and iodine values, tended to decrease slightly by increasing N-rate and the application of growth substances, while a reverse trend was noticed by raising P-level. The mean values of oil specific gravity and refractive index did not show any definite response.  相似文献   
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