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排序方式: 共有613条查询结果,搜索用时 15 毫秒
81.
由于竞争加剧,使纸浆价格持续下跌.为保持活力,北美制浆造纸工业除生产浆纸产品外,需要通过生产生物能源和生物材料来增加收入.这可以藉将硫酸盐浆厂转变为综合林业生物精炼厂而实现. 相似文献
82.
从核酸探针、聚合酶链式反应、分子标记、实时PCR等分子生物学技术在双歧杆菌检测中的应用等方面作以综述,并指出各种检测技术的局限性及应用前景。 相似文献
83.
84.
胡军 《食品与生物技术学报》1984,3(3)
生物工程是应用生物有机体,生物系统或生物过程来制造工业产品的学科。生物工程在应用微生物方面有很悠久的历史。例如酿酒,发酵乳制品奶酪、酸乳等。目前又在发酵罐设计,发酵工艺,酶技术及遗传工程方面具有令人振奋的进展。生物工程学着重微生物学,生物化学和化学工程的结合,并直接付之实用。本综述主要介绍生物工程中几个同发酵有关的内容,即:微生物技术、酶技术及发酵枝术。 相似文献
85.
The jabuticaba tree (Brazilian grape tree) is a tree native to Brazil that belongs to the Myrtaceae family. The jabuticaba fruit is used in some regions of Brazil to produce juices, jams, wine, and ice cream. In this work, the fermentation conditions (temperature and °Brix) for producing jabuticaba distillate were optimized using the response surface methodology (RSM). The optimal conditions for fermentation were found to be 20 °C and 22 °Brix. In repeated experiments to validate the model, experimental data exhibited good agreement with the predicted data. The distillate jabuticaba beverage showed a peculiar chemical composition with 20 volatile compounds that were identified and quantified. Isoamyl alcohols (2-methyl-1-butanol + 3-methyl-1-butanol) were the most abundant volatile compounds identified in jabuticaba spirit. Sensory analysis by tasters showed overall approval of jabuticaba distillate. In principal component analysis, when the beverage was evaluated by panelists under 24 y old tended to give favorable ratings of aroma and taste, as well as high overall scores. The group of panelists between the ages of 25 and 53 y old generally gave high marks for appearance in the principal component analysis. PRACTICAL APPLICATION: This study describes the study of fermentation conditions of jabuticaba pulp for production of jabuticaba spirit. Based on the results of this work, the proposed method can be an alternative for the use of the jabuticaba fruit, and may provide a new industrial outlet for this fruit. 相似文献
86.
87.
《Food Reviews International》2013,29(4):437-473
Abstract Food irradiation is one of the most extensively and thoroughly studied methods of food preservation. Despite voluminous data on safety and wholesomeness of irradiated foods, food irradiation is still a “process in waiting.” Although some countries are allowing the use of irradiation technology on certain foods, its full potential is not recognized. Only 37 countries worldwide permit the use of this technology. If used to its full potential, food irradiation can save millions of human lives being lost annually due to food‐borne diseases or starvation and can add billions of dollars to the world economy. This paper briefly reviews the history and chemistry of food irradiation along with its main applications, impediments to its adoption, and its role in improving food availability and health situation, particularly in developing countries of the world. 相似文献
88.
We assessed the potential public health impacts of foods derived from recombinant DNA technology that have been modified to have improved nutrient profiles using omega-3-enhanced vegetable oils as an example. Other examples of crops in development include canola plants with increased vitamin C and rice with higher levels of beta-carotene. The change in consumption of omega-3 fatty acids if vegetable oils were replaced with stearidonic acid-enhanced versions was estimated. The results showed that stearidonic acid and gamma-linolenic acid consumption would increase by 5.43 g/d for males and 4.14 g/d for females. The increase in stearidonic acid in eicosapentaenoic acid equivalents was 1.63 g/d for males and 1.24 g/d for females. 相似文献
89.
通过介绍生物技术在筛选和培育高含量黄姜皂素品种以及黄姜皂素提取过程中的应用,并对比不同生物法提取工艺对黄姜皂素的提取得率影响,分析了影响生物法提取皂素收率的主要因素,发现酶解法在提取黄姜皂素上相比传统的酸解工艺具有明显的得率优势和环保优势。因此,提出了一种综合利用生物技术提取黄姜皂素的发展思路及评价方法,对黄姜皂素工业化推广具有很好的实际指导作用。 相似文献
90.