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911.
有效合理地存放、保养联合收割机可延长其使用寿命。存放注意事项是每个联合收割机用户都应该了解的,重点包括存放地点的选择,整机、发动机、底盘、割台的处理。 相似文献
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913.
为解决矿区水资源紧缺现象,规划利用塌陷蓄水区水资源成为首选,而掌握塌陷蓄水区水文情况,是塌陷区水资源合理规划利用的前提。以兴隆庄采煤塌陷蓄水区为例,收集整理了蓄水区附近5个水文站1956-2008年降水量及14个地下水观测站1988-2008年地下水位的资料,进行降水量与地下水位分析。结果表明:塌陷蓄水区降水的年度和年内分布不均匀,丰水期和枯水期交替出现。地下水动态类型属于入渗-径流-开采型,随季节和降水量的变化呈现周期性变化,年内变化规律为"下降-上升-下降"3个阶段,地下水流向为东北到西南方向。降水与地下水位关系较为密切,降水量的变化和地下水位年变幅的变化过程趋势一致,且具有滞后性,降水量与延缓1个月的地下水位的线性关系较好。 相似文献
914.
针对特色林果业种植面积快速发展中,现有节水灌溉技术应用于果树灌溉存在一些局限和不完善问题,创新提出基于果树类作物的蓄流分离式灌溉技术模式。以技术理论结合试验示范应用研究范例,分析这一灌溉模式节水增产、节能降耗、提升灌溉水温、定额用水机制,以及取得的技术经济效果。蓄流灌溉新模式对研究拓展不同灌溉作物多元化节水新技术、新方法、新产品,具有重要的现实应用意义。 相似文献
915.
Grete Hansen Aas Olaug Taran Skjerdal Iren Stoknes Ingebrigt Bjørkevoll 《Journal Of Aquatic Food Product Technology》2013,22(3-4):149-161
Different packaging conditions of salt-cured cod fillets were studied during 2-years chilled storage. Yield and quality of salt-cured Atlantic cod fillets packed in sealed polystyrene boxes or in traditional cardboard boxes were compared. After 4 months, yield decreased by approximately 10% and decreased further when packed in cardboard boxes. Lipid oxidation was low after 12 months, and no microbiological spoilage was registered. The total amount of bacteria in the fish reduced with storage time, independent of packaging. The reddish color of halophilic bacteria was detected after 7–8 weeks at 18°C, but not if packed with MAP. 相似文献
916.
ABSTRACTOvalipes trimaculatus is a crab recognized as a new resource with fishing value to obtain frozen products. Pasteurization conditions of meat crab at temperatures below 85ºC (60, 72, and 82ºC) were established to achieve better quality attributes in the frozen product. The lethality curves of Staphylococcus aureus and Listeria monocytogenes were measured, and the decimal reduction times (D) and Z values were determined. Heat transfer during the pasteurization process of pouches containing crab meat was simulated using a computational code in finite elements, and the mathematical model was experimentally validated. Thermal histories were coupled to the microbial lethality kinetics of the most heat resistant pathogen microorganism in order to establish pasteurization times necessary for the process system design. The predicted pasteurization conditions were microbiologically validated. The pouches were frozen under industrial conditions and stored at ?22ºC for 1 year. The influence of the type of packaging (vacuum and nonvacuum plastic pouches) on physicochemical and sensory quality parameters of frozen crab meat (color, exudate, lipid oxidation, water holding capacity, and overall acceptability) were analyzed observing better performance under vacuum conditions. 相似文献
917.
Laura Rodríguez-Turienzo Beatriz Sanmartín Olga Díaz 《Journal Of Aquatic Food Product Technology》2013,22(6):928-939
ABSTRACTThe effects of different egg white protein coatings on Atlantic salmon quality preservation after 4 months of frozen storage were evaluated. These coatings increased the yield of the fillets and protected them from lipid oxidation, providing better protection than glazing. Egg white protein coatings were better options than glazing to preserve salmon color during frozen storage. The best results were obtained with the application of coatings before freezing. No clear effects of the type and concentration of plasticizer in most quality parameters were found. Egg white protein + glycerol 2:1 applied before freezing was the best coating for frozen Atlantic salmon protection. 相似文献
918.
919.
《Journal Of Aquatic Food Product Technology》2013,22(3):35-57
Pacific ocean perch stored under vacuum, 100% CO2 or air at -3°C and 3°C was subjected to sensory, trimethylamine (TMA), color, microbial and volatile analyses. Unpleasant sensory attributes, TMA and microbial content were negatively correlated to overall quality, and Hunter 'L' value increased with storage time. Principal factor analysis of sensory data resulted in three factors that accounted for 71% of the variance, with factor 1 (53%) mainly related to poor quality attributes. Volatiles analyzed by the dynamic headspace technique included alkanes, alkenes, aldehydes, aromatics and alcohols. Canonical variate analysis on volatile compounds separated excellent and poor quality fish samples, while good and medium samples were grouped together. 相似文献
920.
Faisal Rashid Sofi S. M. Zofair Vijay Kumar Reddy Surasani K. K. Sabha Nissar Rajkumar Ratankumar Singh 《Journal Of Aquatic Food Product Technology》2013,22(3):253-263
Fatty fish have been recognized as potential raw material for production of minced meat; however, they are prone to oxidation and further deterioration. In the present study, the effect of washing and antioxidant (tannic acid) treatment on the quality of minced meat of Trachurus trachurus (horse mackerel) during frozen storage was observed. Minced meat of Trachurus trachurus was divided into three lots (T0, T1, and T2). T1 was washed with cold water, T2 with cold water containing tannic acid (100 mg/kg), and T0 was not washed. All the lots were frozen at ?40°C and stored at ?20 ± 2°C for 125 days and were subjected to biochemical, microbiological, and sensory evaluation at regular intervals of 25 days. The antioxidant treatment with tannic acid at the dosage used was found effective in minimizing the rancidity problems of minced meat (T2), compared to T0 and T1. During the whole period of storage, samples from T2 showed good quality in terms of microbiological, biochemical, and sensory analysis compared to T1 and T0. 相似文献