全文获取类型
收费全文 | 1613篇 |
免费 | 140篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 1篇 |
综合类 | 121篇 |
化学工业 | 164篇 |
金属工艺 | 3篇 |
机械仪表 | 9篇 |
建筑科学 | 11篇 |
矿业工程 | 3篇 |
能源动力 | 5篇 |
轻工业 | 1351篇 |
水利工程 | 12篇 |
石油天然气 | 3篇 |
无线电 | 6篇 |
一般工业技术 | 26篇 |
冶金工业 | 16篇 |
自动化技术 | 28篇 |
出版年
2024年 | 11篇 |
2023年 | 38篇 |
2022年 | 39篇 |
2021年 | 105篇 |
2020年 | 63篇 |
2019年 | 82篇 |
2018年 | 63篇 |
2017年 | 70篇 |
2016年 | 60篇 |
2015年 | 47篇 |
2014年 | 99篇 |
2013年 | 90篇 |
2012年 | 116篇 |
2011年 | 122篇 |
2010年 | 56篇 |
2009年 | 50篇 |
2008年 | 49篇 |
2007年 | 73篇 |
2006年 | 96篇 |
2005年 | 84篇 |
2004年 | 82篇 |
2003年 | 47篇 |
2002年 | 36篇 |
2001年 | 23篇 |
2000年 | 19篇 |
1999年 | 23篇 |
1998年 | 8篇 |
1997年 | 10篇 |
1996年 | 13篇 |
1995年 | 6篇 |
1994年 | 14篇 |
1993年 | 9篇 |
1992年 | 12篇 |
1991年 | 11篇 |
1990年 | 10篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 3篇 |
排序方式: 共有1759条查询结果,搜索用时 31 毫秒
1.
Anna Romanotto Jeanette Langner Martin Sander Franziska Müller Walter Vetter 《Journal of the American Oil Chemists' Society》2022,99(6):501-509
Furan fatty acids (FuFAs) are valuable antioxidants with highly effective radical scavenging properties which are widely distributed at low levels in food. Previous research indicated that tea is a valuable source of FuFAs. However, tea is only consumed in form of infusions. To fill this gap, we prepared infusions from different herbal, green, and black teas. Initial measurements with GC-MSMS of tea verified previous findings that 11-(3,4-dimethyl-5-penylfuran-2-yl)-undecanoic acid (11D5) was the prevalent FuFA in tea matrix. Therefore, 11D5 was quantified in tea infusions by means of UHPLC-MSMS equipment after mild alkaline hydrolysis. While herbal tea infusions were low or free of FuFAs, 11D5 was detectable in all samples of green and black tea infusions. Amounts of 11D5 were higher in green tea than in black tea. Moreover, Darjeeling tea infusions were by ~30% richer in 11D5 than black and green teas from other regions. Each cup of green and black tea infusion may provide 20–60 μg 11D5, which is about 5% of the amounts found in tea samples. Spread over the day, regular tea consumption may contribute to the intake of valuable FuFAs. 相似文献
2.
Marthe Jordbrekk Blikra Sigrun Henjum Inger Aakre 《Comprehensive Reviews in Food Science and Food Safety》2022,21(2):1517-1536
Brown algae are becoming increasingly popular as a food source and dietary supplement in Europe and other Western countries. As they are highly rich in iodine, they represent a potential new dietary iodine source. Iodine deficiency has been re-emerging in Europe, and it is important to ensure adequate intake through one's diet. However, macroalgae, and especially brown algae, may contain very high amounts of iodine, and both iodine deficiency and excessive iodine may increase the risk of negative health effects. The iodine content of algae or foods containing algae is currently not regulated in the European Union. The aim of this paper is to review the literature to determine the chemical species of iodine in brown algae, the loss of iodine during processing, and the bioavailability and bioaccessibility of iodine. A systematic search of the literature was performed in April 2021, via the databases Web of Science and PubMed. The review includes studies of iodine in brown macroalgae in relation to bioavailability, bioaccessibility, processing and speciation. A meta-analysis was conducted in relation to the following topics: (i) the correlation between total iodine and iodide (I–) content in brown algae; (ii) the correlation between the loss of iodine during processing and the I– content; and (iii) the correlation between bioavailability and the I– content. The bioavailability of iodine from brown algae was generally high, with in vivo bioavailability ranging from 31% to 90%. The in vitro bioavailability of iodine (2%–28%) was systematically lower than in vivo bioavailability (31%–90%), indicating an inadequate in vitro methodology. Processing may reduce the iodine content of brown algae, and a higher I– content was positively correlated with increased iodine loss during processing. Although processing strategies may reduce the iodine content of brown algae significantly, the iodine content may still be high after processing. These findings may be used in food safety evaluations of brown algae as well as in the development of macroalgae-containing foods with iodine contents suitable for human consumption. Further research on processing techniques to reduce the iodine content in brown macroalgae are warranted. 相似文献
3.
4.
对英国食品每日摄入量指南(GDAs)标签开展案例研究,结果发现,GDAs标签从包装背面标签转为FOP标签,实施已有20年以上。该标签采用特定营养素体系度量法模型,显示每份食品能量、糖、脂肪、饱和脂肪、盐的含量及其每日参考摄入量占比,既没有颜色编码又没有形象的图标显示,且实施效果不如多数FOP标签。对此,中国可考虑将营养成分表信息以食品份量单位直观显示在包装正面,方便消费者关注与理解。 相似文献
5.
6.
7.
Formation,nutritional value,and enhancement of characteristic components in black garlic: A review for maximizing the goodness to humans 总被引:1,自引:0,他引:1
Zhichang Qiu Zhenjia Zheng Bin Zhang Dongxiao Sun‐Waterhouse Xuguang Qiao 《Comprehensive Reviews in Food Science and Food Safety》2020,19(2):801-834
Black garlic (BG) is essentially a processed food and obtained through the transformation of fresh garlic (FG) (Allium sativum L.) via a range of chemical reactions (including the Maillard reaction) and microbial fermentation. This review provides the up‐to‐date knowledge of the dynamic and complicated changes in major components during the conversion of FG to BG, including moisture, lipids, carbohydrates (such as sugars), proteins, organic acids, organic sulfur compounds, alkaloids, polyphenols, melanoidins, 5‐hydroxymethylfurfural, vitamins, minerals, enzymes, and garlic endophytes. The obtained evidence confirms that BG has several advantages over FG in certain product attributes and biological properties (especially antioxidant activity), and the factors affecting the quality of BG include the type and characteristics of FG and processing technologies and methods (especially pretreatments, and processing temperature and humidity). The interactions among garlic components, and between garlic nutrients and microbes, as well as the interplay between pretreatment and main manufacturing process, all determine the sensory and nutritional qualities of BG. Before BG is marketed as a novel snack or functional food, more research is required to fill the knowledge gaps related to quantitative monitoring of the changes in metabolites (especially those taste‐active and/or biological‐active substances) during BG manufacturing to maximize BG's antioxidant, anticancer, antiobesity, anti‐inflammatory, immunostimulatory, anti‐allergic, hepatoprotective, cardioprotective and oxidative stress‐/hangover syndrome‐reducing functions, and beneficial effects on memory/nervous systems. Assessments of the quality, efficacy, and safety of BG should be performed considering the impacts of BG production conditions, postproduction handling, and intake methods. 相似文献
8.
9.
韩玲 《食品安全质量检测学报》2020,11(21):7771-7776
肌酸(creatine)是脊椎动物体内自然存在的一种含氮类有机酸。补充肌酸能够通过调节体内磷酸肌酸水解、糖代谢和蛋白表达等方式来增加糖原的储存、提高ATP的生成、增强肌细胞的酸碱缓冲能力以及刺激肌细胞增殖,从而能够预防运动损伤、改善运动表现、提升训练适应性和加快运动后康复。自从1992年巴塞罗那奥运会上,英国短跑运动员克利斯提通过服用肌酸提高运动能力,并夺得百米冠军后,欧美运动员开始广泛的在运动和训练时服用肌酸,到1996年亚特兰大奥运会,已有60%以上的短跑运动员服用肌酸。对于从事剧烈运动训练的高水平运动员而言,需要每天摄入5-10 g肌酸以维持最佳的全身肌酸储备量,从而保持最佳的运动和训练效果。本文详细综述了肌酸的作用机制、补充肌酸对运动能力的影响、补充肌酸的安全性以及肌酸类运动营养品的使用人群、产品种类、补充策略和相关标准法规等。 相似文献
10.