全文获取类型
收费全文 | 7902篇 |
免费 | 1025篇 |
国内免费 | 600篇 |
专业分类
电工技术 | 917篇 |
综合类 | 737篇 |
化学工业 | 496篇 |
金属工艺 | 252篇 |
机械仪表 | 578篇 |
建筑科学 | 499篇 |
矿业工程 | 212篇 |
能源动力 | 201篇 |
轻工业 | 430篇 |
水利工程 | 88篇 |
石油天然气 | 144篇 |
武器工业 | 81篇 |
无线电 | 2501篇 |
一般工业技术 | 553篇 |
冶金工业 | 299篇 |
原子能技术 | 79篇 |
自动化技术 | 1460篇 |
出版年
2024年 | 37篇 |
2023年 | 104篇 |
2022年 | 209篇 |
2021年 | 235篇 |
2020年 | 292篇 |
2019年 | 244篇 |
2018年 | 214篇 |
2017年 | 323篇 |
2016年 | 337篇 |
2015年 | 312篇 |
2014年 | 504篇 |
2013年 | 556篇 |
2012年 | 614篇 |
2011年 | 577篇 |
2010年 | 471篇 |
2009年 | 434篇 |
2008年 | 466篇 |
2007年 | 518篇 |
2006年 | 477篇 |
2005年 | 391篇 |
2004年 | 365篇 |
2003年 | 314篇 |
2002年 | 281篇 |
2001年 | 265篇 |
2000年 | 212篇 |
1999年 | 165篇 |
1998年 | 120篇 |
1997年 | 109篇 |
1996年 | 85篇 |
1995年 | 58篇 |
1994年 | 48篇 |
1993年 | 41篇 |
1992年 | 32篇 |
1991年 | 31篇 |
1990年 | 22篇 |
1989年 | 10篇 |
1988年 | 19篇 |
1987年 | 11篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 6篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有9527条查询结果,搜索用时 15 毫秒
1.
Ligang Yu Yong Li Yukun Yang Caixia Guo Meiping Li 《International Journal of Food Science & Technology》2022,57(7):4646-4655
This study investigated the inhibitory effects of curcumin and piperine on fluorescent advanced glycation end products (fAGEs) formation in a bovine serum albumin (BSA)–fructose model. Model systems of BSA and fructose were prepared, and curcumin or piperine was added. fAGEs and BSA oxidation product (dityrosine, kynurenine and N'-formylkynurenine) contents were determined. The results showed that fAGEs content decreased with increasing concentration of curcumin and piperine (P < 0.05). Addition of curcumin and piperine at 160 µg mL−1 could inhibit fluorescent AGEs by 100% and 93% respectively. Dityrosine and N'-formylkynurenine contents decreased as curcumin and piperine concentration increased (P < 0.05). Furthermore, the result of principal component analysis indicated that curcumin and piperine markedly impeded BSA oxidation, resulting in a lower level of fAGEs in model systems. Therefore, adding curcumin and piperine may facilitate reduced fAGEs levels in BSA–fructose model. 相似文献
2.
Qiaozhi Zhang Yanbo Wang Linglin Fu 《Comprehensive Reviews in Food Science and Food Safety》2020,19(5):2559-2587
Dietary advanced glycation end products (dAGEs) are complex and heterogeneous compounds derived from nonenzymatic glycation reactions during industrial processing and home cooking. There is mounting evidence showing that dAGEs are closely associated with various chronic diseases, where the absorbed dAGEs fuel the biological AGEs pool to exhibit noxious effects on human health. Currently, due to the uncertain bioavailability and rapid renal clearance of dAGEs, the relationship between dAGEs and biological AGEs remains debatable. In this review, we provide the most updated information on dAGEs including their generation in processed foods, analytical and characterization techniques, metabolic fates, interaction with AGE receptors, implications on human health and reducing strategies. Available evidence demonstrating a relevance between dAGEs and food allergy is also included. AGEs are ubiquitous in foods and their contents largely depend on the reactivity of carbonyl and amino groups, along with surrounding condition mainly pH and heating procedures. Once being digested and absorbed into the circulation, two separate pathways can be involved in the deleterious effects of dAGEs: an AGE receptor‐dependent way to stimulate cell signals, and an AGE receptor‐independent way to dysregulate proteins via forming complexes. Inhibition of AGEs formation during food processing and reduction in the diet are two potent approaches to restrict health‐hazardous dAGEs. To elucidate the biological role of dAGEs toward human health, the following significant perspectives are raised: molecular size and complexity of dAGEs; interactions between unabsorbed dAGEs and gut microbiota; and roles played by concomitant compounds in the heat‐processed foods. 相似文献
3.
针对现有混合入侵检测模型仅定性选取特征而导致检测精度较低的问题,同时为了充分结合误用检测模型和异常检测模型的优势,提出一种采用信息增益率的混合入侵检测模型.首先,利用信息增益率定量地选择特征子集,最大程度地保留样本信息;其次,采用余弦时变粒子群算法确定支持向量机参数构建误用检测模型,使其更好地平衡粒子在全局和局部的搜索能力,然后,选取灰狼算法确定单类支持向量机参数构建异常检测模型,以此来提高对最优参数的搜索效率和精细程度,综合提高混合入侵检测模型对攻击的检测效果;最后,通过两种数据集进行仿真实验,验证了所提混合入侵检测模型具有较好的检测性能. 相似文献
4.
5.
6.
7.
8.
9.
The aim of this paper is to give a general quantitative requirement which the loop gain must satisfy in order to stabilize a given unstable (possibly nonlinear and time-varying) plant, namely that the gain must exceed one. 相似文献
10.