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81.
Information on the addition of lipase and/or emulsifiers to less digestible or saturated fat sources, such as tallow or other animal fats, used in swine feeding is very limited. Therefore, in a 4 × 4 Latin square design, the effects of adding lipase (0.05% L5, microbial source) and/or an emulsifier (0.3% Lysoforte) on the apparent ileal (AID) and faecal (AFD) digestibility of the main nutrients and fatty acids in particular were studied with four ileal‐cannulated growing pigs (female, initial live weight 20 kg) fed diets containing barley/soybean meal supplemented with 4% animal fat. The fat source contained 35% saturated (S) and 65% unsaturated (U) fatty acids. All diets were free of antibacterial substances (antibiotics, copper sulphate or zinc oxide beyond requirements), in order to avoid interactions between the parameters studied and the gut flora. Lipase addition did not affect the AID or AFD of fat. However, the digestibility of minor fatty acids (C6:0, C14:0) was significantly improved by lipase at both ileal and faecal level. On the other hand, lipase supplementation (P < 0.05) improved the AID of dry matter (DM) and energy as well as the AFD of DM, organic matter (OM), crude protein (CP), ash and energy. Addition of an emulsifier did not have any significant influence on the AID or AFD of fat, while the AID values of DM, OM, CP and energy as well as the AFD values of DM, OM, CP and ash were significantly (P < 0.05) improved. Adding lipase in combination with an emulsifier to the diets decreased (P < 0.05) the AID and AFD of fat, with minor effects on the AID and AFD of the non‐fat components of the diet. The lack of improvement in the digestion of fat by exogenous lipase and/or emulsifier may be related to the rather high U/S ratio (0.65:0.35) of the animal fat source used and to the mode of incorporation of the emulsifier (no pre‐dispersion in the fat source). Furthermore, during the trial the diets, stored at room temperature, showed a steady increase in their content of free fatty acids (to more than 700 g kg?1 fat), due to endogenous lipase activity, leaving less room for upgrading the digestion of animal fat by exogenous lipase and/or emulsifier. Copyright © 2004 Society of Chemical Industry 相似文献
82.
Musgrove MT Jones DR Northcutt JK Curtis PA Anderson KE Fletcher DL Cox NA 《Journal of food protection》2004,67(12):2801-2804
To successfully implement a hazard analysis critical control point plan, prerequisite programs are essential. Sanitation standard operating procedures are an important part of such a plan and can reduce contamination levels so that food safety and quality are not adversely affected. Noncontact surfaces in the shell egg processing plants can serve as a reservoir of cross-contamination. The objective of this study was to assess the efficacy of sanitation programs used in a variety of shell egg processing facilities (in-line, off-line, and mixed operations). Fourteen different noncontact surfaces were sampled in nine commercial facilities across the southeastern United States. Non-egg-contact surfaces were defined as those where the shell egg does not come into direct contact with the surface or with the fluid from that surface. Gauze pads soaked in sterile phosphate-buffered saline were used for sampling at the end of a processing day (POST) and again the next morning prior to operations (PRE). Aerobic plate counts (APCs) and numbers of Enterobacteriaceae were determined. No significant differences (P > 0.05) were found between POST and PRE counts for either population recovered from the 14 sampling sites. Only samples from the floor under the farm belts, nest-run loader, washers, and packer heads were reduced by 1 log CFU/ml of rinsate for APCs or Enterobacteriaceae counts. APCs of more than 10(4) CFU/ml of rinsate were recovered from many samples. Highest APCs were found on the floor under the farm belt and on shelves of the nest-run carts. High APCs were found on the wheel surface for off-line carts and on the loading dock floor. Highest Enterobacteriaceae counts were found in samples from the floor, drain, and nest-run egg cart shelves. A lack of significant difference between POST and PRE counts indicates that current sanitation programs could be improved. These data suggest that traffic patterns for the movement of eggs and materials through the plant should be reevaluated so that cross-contamination is reduced. 相似文献
83.
Addis E Fleet GH Cox JM Kolak D Leung T 《International journal of food microbiology》2001,69(1-2):25-36
The growth of yeasts and bacteria were monitored during the maturation of Camembert and blue-veined cheese produced in Australia. Yeasts were prominent throughout maturation, growing to 10(5)-10(9)/g, depending on the manufacturer. Debaryomyces hansenii predominated, but there were lesser, inconsistent contributions from Yarrowia lipolytica. Of the non-lactic acid bacteria, Acinetobacter species were significant during the maturation of Camembert but not blue-veined cheeses, and grew to 10(6)-10(8) cfu/g. Staphylococcus and Micrococcus species were consistently isolated from the cheeses with Staphylococcus xylosus growing to 10(5)-10(9) cfu/g, depending on the product. Lactic acid bacteria (10(7)-10(9) cfu/g) were present throughout maturation but were not identified. Interactions between the various yeasts and bacterial isolates were examined. Several strains of D. hansenii exhibited killer activity but not against Y. lipolytica. None of the yeasts were antagonistic towards the bacteria but some strains of D. hansenii enhanced the growth of Y. lipolytica and S. xylosus. The yeast and bacterial isolates exhibited various degrees of extracellular proteolytic and lipolytic activities. 相似文献
84.
Netsayi Noris Mudege Sarah Mayanja John Nyaga Mariam Nakitto Samuel Edgar Tinyiro Damali Babirye Magala Janet Cox Achora Sarah Kisakye David Bamwirire Thiago Mendes Tawanda Muzhingi 《International Journal of Food Science & Technology》2021,56(3):1362-1375
Using quantitative, qualitative and sensorial data collected from western (Kabale) and central (Rakai) Uganda, this paper identifies and describes gender-responsive traits preferred in varieties for the boiled potato market. These traits are aggregated into a product profile to support breeding programme design and decision-making that will increase probability of variety acceptance. An interdisciplinary and participatory methodology was used to collect data on socio-economic on trait preferences, processing and organoleptics and finally, to develop a lexicon through a sensorial panel. Characteristics that were important to both men and women, such as red skin and yellow flesh, are linked to market preferences. Women-only preferred characteristics such as big size and mealiness are linked to processing efficiency and eating quality. Besides agronomic traits, breeders must consider factors such as gender roles, social norms, and market preferences traits that guide farmers and other food chain actors in their selection of new varieties. 相似文献
85.
以玉米须与水芹为主要原料,选用酿酒酵母作为发酵菌种,按比例进行混合发酵,考察玉米须水芹酒最佳酿造工艺。以酒精度和感官评分为检测指标,运用单因素试验和Box-Behnken 中心组合试验优化发酵条件,对水芹汁与玉米须汁的体积比、菌种添加量、发酵时间以及发酵温度进行控制,得到最佳的发酵工艺条件为水芹汁∶玉米须汁=1 ∶2(体积比)、菌种添加量0.6%、发酵时间11 d、发酵温度25 ℃。在该条件下得到的玉米须水芹酒呈淡黄色透明状,酒香醇厚,酒体柔和,且具有一定的抗氧化能力。 相似文献
86.
Interactive computer guidance systems are discussed. The user interface of such systems and the computer resources required are examined for a large computer centre. The design and development of a Liverpool HELP system is discussed. The Liverpool HELP system, which is written entirely in GEORGE job control language, is shown to be an efficient and inexpensive solution to the provision of an on-line enquiry service. 相似文献
87.
Pseudomonas fluorescens UQM2490, resistant to 250 μg rifampicin/ml, was derived from P. fluorescens JC1, a proteolytic psychrotroph isolated from raw milk. Growth of UQM2490 was followed in raw and ultra heat-treated milk, by viable counting on rifampicin-containing agar medium. The growth curves obtained demonstrate slower growth in raw milk than in treated milk and the variation in growth with change in inoculum level. Generation times in ultra heat-treated milk ranged from 9.5 to 14.1 h compared with 9.6 to 33 h in raw milk. 相似文献
88.
89.
【摘要】 目的 探讨Pipeline栓塞装置(PED)治疗颈内动脉海绵窦段动脉瘤(CCA)和颈内动脉眼动脉段动脉瘤(COA)的安全性和有效性。方法 回顾性分析2015年7月至2016年12月南京鼓楼医院经DSA确诊为CCA、COA及多发动脉瘤并接受PED治疗患者的临床资料。结果 共纳入21例患者(27枚动脉瘤),其中男4例,女17例;年龄27~74岁,平均(57±17)岁;大型/巨大型CCA、COA 15例,多发性COA 5例,微小型COA 1例;平均瘤体直径10.2 mm(2.5~25.3 mm)。术中共植入24枚PED(3例各植入2枚);18例PED结合弹簧圈疏松栓塞,3例仅植入PED。术后即刻造影显示瘤腔内对比剂不同程度滞留,大型/巨大型动脉瘤可见典型“半月征”,载瘤动脉均通畅。术后随访6~12个月,所有患者症状均得到缓解,动脉瘤完全闭塞率为 88.9%(24/27)。结论 PED治疗CCA、COA及多发动脉瘤安全有效,随访结果满意。但仍需大样本远期前瞻性随访验证。
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90.
猴头菌是传统的食药两用菌,具有猴头菌多糖、猴头菌素、猴头菌酮、麦角甾醇等多种活性成分,对胃炎、胃溃疡、胃癌等胃部疾病具有有益调节作用。猴头菌有子实体和菌丝体两种形态,菌丝体又分为固态发酵菌丝体与液态发酵菌丝体。本文主要对比阐述了猴头菌子实体与液态发酵菌丝体活性成分差异以及它们在改善胃部疾病中相关研究成果,以期为猴头菌液态发酵菌丝体规模化、工业化、自动化生产,以及功能食品和食用菌基天然药物的开发提供依据和参考。 相似文献