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981.
板栗碳素营养与花性的表现 总被引:13,自引:1,他引:12
板栗叶片,花芽及枝皮中蔗糖,还原糖,淀粉等含量变化动态与花性表现关系的研究结果表明,不同性别表现的花芽对蔗糖的利用时机不同,雌性表现与蔗糖的消长动态关系最为密切;雌花出现前,雄花序大量发生和生长,消耗大量的淀粉和还原糖;新梢由迅速生长期进入缓慢生长期是碳素营养代谢的一个转折点,此时结果枝叶,雄花枝叶及营养枝叶中还原糖含量急剧升高,蔗糖含量大幅度降低,结果母枝上部及中部枝皮中蔗糖含量迅速增加,此期是 相似文献
982.
Gahlawat Poonam Sehgal Salil 《Plant foods for human nutrition (Dordrecht, Netherlands)》1998,52(2):151-160
A technique for development of potato flour was standardized. Five products viz. cake, biscuit, weaning food, panjiri and ladoo were prepared incorporating potato flour, defatted soy flour and corn flour. Baking and roasting were the major processing techniques employed for the development of these products. Protein, ash and fat contents of potato flour were almost similar to those of raw potatoes. Significant differences in protein, ash and fat contents of all the products were observed. Protein and starch digestibility of potato flour was significantly higher than that of raw potatoes. Protein digestibility increased by 12 to 17 percent on baking or roasting of products. Processed products had significantly higher starch digestibility and mineral availability compared to raw products. Thus, it can be concluded that roasting and baking are effective means of improving starch and protein digestibility and mineral availability of products. 相似文献
983.
冷水胁迫对云南粳稻品质性状的影响 总被引:7,自引:2,他引:7
以11个云南粳稻品种为试验材料,研究冷水胁迫对稻米品质性状的影响以及水稻耐冷性与品质性状冷水反应的相关关系。结果表明,品质性状的冷水反应不仅与品种有关,也与具体的品质性状有关。冷水胁迫使粒宽、千粒重、垩白粒率、精米白度、糙米率、味度值、最高黏度、最低黏度、崩解值、最终黏度显著或极显著降低,使长宽比、整精米率、碱消值、蛋白质含量和消减值极显著增加,而粒长、精米率、直链淀粉含量、到达最高黏度时间(峰值时间)和起浆温度不因冷水胁迫发生明显变化。相关分析表明,成熟期综合耐冷性与稻米的味度值、蛋白质含量、最高黏度和崩解值的冷水反应指数具有显著或极显著相关性。因此,提高育成品种的耐冷性对稳定和改善稻米食味品质具有重要作用。 相似文献
984.
不同施肥水平对春小麦籽粒淀粉,蛋白质积累的影响 总被引:9,自引:0,他引:9
利用产量和蛋白质含量各异的三个春小麦品种,采用盆栽试验,研究了低肥和高肥水平条件下籽粒淀粉,蛋白质积累。结果表明,施肥能明显增加前期籽粒淀粉的积累,对后期的影响表现出品种间的差异,但对各品种籽粒成熟时的淀粉含量影响不大;蛋白质在积累与施肥水平关系不大,但高肥条件有减少蛋白质含量的趋势。提出小麦高产优质施肥,应在注重土壤肥力的前提下,强调后期氮肥的应用。 相似文献
985.
Comparison of structural and physicochemical properties of potato protein and potato flour modified with tyrosinase
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ZHU Yu YUAN Yu-han MEI Li-ping DING Shuang-kun GAO Yu-chen DU Xian-feng GUO Li 《农业科学学报》2022,21(5):1513-1524
The present study modified potato protein and flour with tyrosinase to promote the diversification of potato staple foods.The results indicated that tyrosinase treatment markedly altered the secondary structure of proteins.After tyrosinase treatment,the maximum decomposition temperature of potato protein and flour increased from 322.32 to 332.40℃ and from 294.24 to 299.61℃,respectively.Tyrosinase treatment remarkably reduced the pasting viscosity of potato flour,that is,the peak viscosity,throug... 相似文献
986.
糯质玉米品质优良,柔软香甜,风味独特,营养丰富,是轻工业的上等原料;糯玉米淀粉或其变性淀粉在制糖、酿造、食品和粘合剂生产等方面均有广泛的应用前景,糯玉米是发展高产、优质、高效农业的重要经济作物之一。 相似文献
987.
以中国水仙‘金盏银台’品种3年生休眠鳞茎为试验材料,研究在5、15、25、35℃和室温(CK)贮藏下鳞茎内鳞片、外鳞片和主芽的可溶性糖和淀粉含量的变化。结果表明:鳞茎内鳞片、外鳞片和主芽淀粉含量变化受贮藏温度的影响显著;不同贮藏温度下内鳞片、外鳞片和主芽的可溶性糖含量都基本稳定在一定的水平,而淀粉含量整体波动较大。在鳞茎贮藏期的叶芽和花芽分化期间,不同温度对淀粉水解产生显著影响,对可溶性糖的影响不显著,淀粉水解跟主芽的发育密切相关。因此,通过淀粉来研究了解水仙鳞茎贮藏期间碳水化合物的变化更适宜。 相似文献
988.
989.
Shin-Ho?Park Soon-Yeong?Cho Meiko?Kimura Hisanori?Nozawa Nobuo?SekiEmail author 《Fisheries Science》2005,71(4):896-903
ABSTRACT: The addition of microbial transglutaminase (MTGase) to salted squid muscle paste greatly strengthened the elasticity of the thermal gel, which was produced by the preferential cross-linking of myosin heavy chains through a two-step heating process that consisted of setting at 40°C and subsequent heating to 80°C or 90°C. Starch increased the breaking strength of thermal squid gels, but decreased the deformation. Thus, the starch-added gels became harder and less elastic. Although, when both MTGase and starch were added to squid muscle paste, the changes in viscoelastisity and myosin cross-linking reaction were similar to those with MTGase alone during setting, the storage and loss moduli of the paste sharply increased with an increase in starch content above 70°C. Subsequently, the thermal gel texture became more brittle or breakable than gels prepared by setting with MTGase only. 相似文献
990.
The aim of the study was to investigate the effect of starch source, retention time in the preconditioner and screw speed (RPM) on physical quality of extruded fish feeds. The experiment was arranged in a three by two by two factorial design using three carbohydrate sources [wheat starch (WS), pea starch (PS) or a combination (WS_PS)], two retention times in the preconditioner [long (120 s) or short (62 s)] and two RPM in the extruder [high (300) or low (220)]. Physical quality was assessed by hardness, diameter, expansion ratio, Holmen durability (HDI), DORIS value (DV), oil absorption capacity, oil leakage and pasting viscosity. The results showed that retention time in the preconditioner only affected HDI and oil leakage. Long retention time improved HDI but caused a greater leakage. Changing screw speed from 220 to 300 RPM gave a greater expansion ratio, improved HDI and oil absorption. PS resulted in higher pasting viscosity, HDI and DV, but a generally lower hardness than WS. To conclude, PS and WS have different processing characteristics, and the conditions need to be adjusted according to the starch source used when producing extruded fish feed. 相似文献