全文获取类型
收费全文 | 474459篇 |
免费 | 8683篇 |
国内免费 | 1538篇 |
专业分类
电工技术 | 8232篇 |
综合类 | 677篇 |
化学工业 | 74495篇 |
金属工艺 | 17832篇 |
机械仪表 | 14889篇 |
建筑科学 | 10680篇 |
矿业工程 | 2349篇 |
能源动力 | 13448篇 |
轻工业 | 39943篇 |
水利工程 | 4920篇 |
石油天然气 | 8293篇 |
武器工业 | 30篇 |
无线电 | 53030篇 |
一般工业技术 | 93809篇 |
冶金工业 | 89237篇 |
原子能技术 | 9591篇 |
自动化技术 | 43225篇 |
出版年
2022年 | 3911篇 |
2021年 | 5936篇 |
2020年 | 4393篇 |
2019年 | 5470篇 |
2018年 | 8815篇 |
2017年 | 8789篇 |
2016年 | 9389篇 |
2015年 | 6132篇 |
2014年 | 9595篇 |
2013年 | 24909篇 |
2012年 | 15267篇 |
2011年 | 19446篇 |
2010年 | 15404篇 |
2009年 | 16785篇 |
2008年 | 16946篇 |
2007年 | 16352篇 |
2006年 | 14369篇 |
2005年 | 12910篇 |
2004年 | 12225篇 |
2003年 | 12073篇 |
2002年 | 11369篇 |
2001年 | 10988篇 |
2000年 | 10172篇 |
1999年 | 10571篇 |
1998年 | 28745篇 |
1997年 | 19721篇 |
1996年 | 14828篇 |
1995年 | 10797篇 |
1994年 | 9383篇 |
1993年 | 9477篇 |
1992年 | 6493篇 |
1991年 | 6170篇 |
1990年 | 6048篇 |
1989年 | 5692篇 |
1988年 | 5425篇 |
1987年 | 4744篇 |
1986年 | 4597篇 |
1985年 | 5134篇 |
1984年 | 4693篇 |
1983年 | 4183篇 |
1982年 | 3907篇 |
1981年 | 4014篇 |
1980年 | 3716篇 |
1979年 | 3496篇 |
1978年 | 3489篇 |
1977年 | 4192篇 |
1976年 | 5710篇 |
1975年 | 2992篇 |
1974年 | 2771篇 |
1973年 | 2866篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Klimis?S.?NtalianisEmail author Anastasios?D.?Doulamis Nikolaos?D.?Doulamis Nikos?E.?Mastorakis Athanasios?S.?Drigas 《Journal of Signal Processing Systems》2015,80(2):153-161
In this paper, we present a novel memory access reduction scheme (MARS) for two-dimension fast cosine transform (2-D FCT). It targets programmable DSPs with high memory-access latency. It reduces the number of memory accesses by: 1) reducing the number of weighting factors and 2) combining butterflies in vector-radix 2-D FCT pruning diagram from two stages to one stage with an efficient structure. Hardware platform based on general purpose processor is used to verify the effectiveness of the proposed method for vector-radix 2-D FCT pruning implementation. Experimental results validate the benefits of the proposed method with reduced memory access, less clock cycle and fewer memory space compared with the conventional implementation. 相似文献
2.
3.
Deborah Oliveira De Fusco Leonardo Lucas Madaleno Vanildo Luiz Del Bianchi Aline da Silva Bernardo Rafael Roberto Assis Gustavo Henrique de Almeida Teixeira 《International Journal of Food Science & Technology》2019,54(7):2416-2424
Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences. 相似文献
4.
Ana Clara Sabbione Santiago Suárez María Cristina Añón Adriana Scilingo 《International Journal of Food Science & Technology》2019,54(5):1506-1513
In this study, amaranth flour was used as an ingredient to prepare gluten-free cookies. The production process and attributes of amaranth cookies were characterised, and the potential use of amaranth flour as a functional ingredient was analysed. Cookies exhibited a non-uniform reddish brown colour and a cookie factor ratio of 4.5 ± 0.6. Storage studies indicated that after 3 weeks at room temperature cookies presented slight variations in the texture. Simulated gastrointestinal digestion of this product was able to release peptides capable of exerting potential antithrombotic and antihypertensive activities, IC50 values of 0.22 ± 0.04 and 0.23 ± 0.03 mg mL−1 protein, respectively. This work demonstrates for the first time that food made with amaranth flour exerts potential antithrombotic and antihypertensive activity. In conclusion, these amaranth cookies could be an alternative way of incorporating potentially health beneficial products for people who choose a conscious diet, including coeliac or vegan consumers. 相似文献
5.
6.
7.
8.
Ryszard Żywica Monika Modzelewska-Kapituła Katarzyna Tkacz 《International Journal of Food Properties》2018,21(1):1386-1394
The aim of the present study was to determine mathematical relationships between pH changes in beef 24 h post-slaughter and changes in the intensity of electrical current flowing through bull and heifer carcasses during high-voltage electrical stimulation. The electrical stimulation was applied 40 min postmortem for 120 s. The pH values of m. longissimus thoracis et lumborum were analyzed in the function of electrical current intensity changes and its change during electrical stimulation. Mathematical linear correlations of the y = ax ± b type were demonstrated between pH values at 2, 6, and 24 h postmortem and the initial (Ii) and ultimate (Iu) electrical current intensity values, the difference between them and the initial pH values determined before electrical stimulation. High multiple correlation coefficients (R2 = 0.416, α ≤ 0.001) between Iu and pH values 24 h post-slaughter enabled concluding that there is a possibility to predict a pH value of stimulated carcass with high accuracy, and thus also beef quality, based merely on the ultimate electrical current intensity values. 相似文献
9.
María D Torres Herminia Domínguez 《International Journal of Food Science & Technology》2020,55(6):2296-2304
Potato processing industry has a high degree of discarding, which currently has low added value being used primarily for animal feed. However, potato wastes offer a broad range of interesting components such as antioxidants, starch, protein or fibre with potential applications in the food and non-food industries. The recovery of these high valuable fractions using efficient multistage and multiproduct processes could be of great interest. This short review provides a general overview on the integral valorisation of potato wastes, offering an updated vision of the main residual parts generated during potato harvesting and processing, the high valuable obtained components focusing on the bioactive ones and the potential of the emerging extraction techniques over conventional ones. In addition, innovative applications are discussed to highlight the scientific and applied interest of these underutilised and undervalued fractions and to emphasise the integral valorisation of raw materials. 相似文献
10.
Gomes A. C. S. A. Costa L. C. Brito D. C. Frana R. J. Marques Mnica R. C. 《Polymer Bulletin》2020,77(4):1969-1981
Polymer Bulletin - In this study, we synthesized a new ion-imprinted polymer (IIP) based on introduction of amidoxime groups in acrylonitrile, complexation with Cd2+ ions and polymerization with... 相似文献