全文获取类型
收费全文 | 123031篇 |
免费 | 9619篇 |
国内免费 | 4886篇 |
专业分类
电工技术 | 6664篇 |
技术理论 | 12篇 |
综合类 | 7662篇 |
化学工业 | 20797篇 |
金属工艺 | 6389篇 |
机械仪表 | 7457篇 |
建筑科学 | 9537篇 |
矿业工程 | 3294篇 |
能源动力 | 3405篇 |
轻工业 | 7927篇 |
水利工程 | 1978篇 |
石油天然气 | 6854篇 |
武器工业 | 796篇 |
无线电 | 15134篇 |
一般工业技术 | 15417篇 |
冶金工业 | 6225篇 |
原子能技术 | 1426篇 |
自动化技术 | 16562篇 |
出版年
2024年 | 412篇 |
2023年 | 1873篇 |
2022年 | 3043篇 |
2021年 | 4539篇 |
2020年 | 3427篇 |
2019年 | 2853篇 |
2018年 | 3311篇 |
2017年 | 3751篇 |
2016年 | 3284篇 |
2015年 | 4413篇 |
2014年 | 5559篇 |
2013年 | 7077篇 |
2012年 | 7499篇 |
2011年 | 8097篇 |
2010年 | 7063篇 |
2009年 | 6949篇 |
2008年 | 6932篇 |
2007年 | 6422篇 |
2006年 | 6684篇 |
2005年 | 5996篇 |
2004年 | 4074篇 |
2003年 | 3578篇 |
2002年 | 3250篇 |
2001年 | 3116篇 |
2000年 | 3157篇 |
1999年 | 3621篇 |
1998年 | 3064篇 |
1997年 | 2691篇 |
1996年 | 2412篇 |
1995年 | 1998篇 |
1994年 | 1604篇 |
1993年 | 1253篇 |
1992年 | 994篇 |
1991年 | 753篇 |
1990年 | 617篇 |
1989年 | 515篇 |
1988年 | 402篇 |
1987年 | 297篇 |
1986年 | 205篇 |
1985年 | 171篇 |
1984年 | 96篇 |
1983年 | 77篇 |
1982年 | 89篇 |
1981年 | 59篇 |
1980年 | 45篇 |
1979年 | 34篇 |
1978年 | 28篇 |
1977年 | 26篇 |
1976年 | 41篇 |
1973年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
51.
52.
53.
电网的安全水平主要取决于其使用产品的质量是否过关。如果产品的质量较好,则能建造出优质的电网,电网的安全水平便会随之提高。因此,应加强对产品质量的监督管理,从而提高电网的安全水平。我们可建立质量监督管理系统,及时抽检出质量不过关的产品,从而消除电网运行过程中潜在的安全隐患。 相似文献
54.
Multimedia Tools and Applications - We present three stages of a novel backgrounds subtraction method in this paper: a new pixel-block based randomized arrangement is utilized to preprocess all the... 相似文献
55.
Journal of Porous Materials - In this work, a trifluoromethanesulfonic acid (TFOH) modified clay (TFOH-Clay) was developed for the removal of trace olefins in heavy naphtha. 5%TFOH-Clay can... 相似文献
56.
Scientometrics - In this study, scholarly communication systems provided by commercial services and open access systems are examined on the basis of the comprehensiveness and uniqueness of their... 相似文献
57.
Scientometrics - Specialized academic social networking sites are gaining popularity in scientific communication. A huge volume of interdisciplinary information is generated when researchers from... 相似文献
58.
Qin-yu Zhou Shan Zhao Yan-yan Huang Jin-shuang Hu Jia-hua Kuang Dong-mei Liu Charles S. Brennan 《International Journal of Food Science & Technology》2021,56(6):2992-3003
Yogurt preserves and enhances nutritional value of milk. In this study, we have compared several strains to determine the physicochemical, sensory, rheological and aroma characteristics of different yogurts. We used Lactobacillus gasseri LGZ 1029 (LG), commercial probiotic L. rhamnosus (LGG) and traditional fermentation strains Streptococcus thermophilus and L. bulgaricus (SL). Results showed that the flavour and texture characteristics of mixed-strain yogurts were obviously better than in single-strain yogurts. Addition of LG increased pseudoplastic behaviour, as shown by Herschel–Bulkley model analysis of rheological behaviour. The LG + SL group also had both the highest viscosity consistency index and thickening ability. In addition, a total of 57 volatile compounds were detected in yogurts and the fermentation with the addition of LG was mainly affected by ketones. Our study suggested that a yogurt with new attributes can be produced by using LGZ 1029. 相似文献
59.
Mengting Ma Zijun Li Feng Yang Huaixiang Wu Wuyang Huang Zhongquan Sui Harold Corke 《International Journal of Food Science & Technology》2021,56(7):3607-3617
Waxy, normal and high-amylose maize starches were subjected to heat-moisture treatment (HMT) and then added to wheat flour (WF) in different ratios (1%, 5% and 10%). The properties of blends and their cooked noodles were studied to investigate the effects of HMT starches. The incorporation of HMT starch in WF led to an increase in swelling power, peak viscosity and breakdown and to a decrease in setback, thus inhibiting retrogradation, hence enhancing resultant noodle softness. Compared to the same addition ratio of native starch to WF, HMT starch led to higher tensile strength and extensibility in resultant noodles. WF with added HMT starch had higher resistant starch than with native starch. This study showed that addition of HMT maize starch has potential to bring nutritional benefits. However, it is necessary to select the proper blending ratio and amylose content of starch to add, in consideration of its effect on noodle quality. 相似文献
60.