全文获取类型
收费全文 | 1671篇 |
免费 | 175篇 |
国内免费 | 77篇 |
学科分类
工业技术 | 1923篇 |
出版年
2024年 | 13篇 |
2023年 | 29篇 |
2022年 | 58篇 |
2021年 | 82篇 |
2020年 | 65篇 |
2019年 | 89篇 |
2018年 | 64篇 |
2017年 | 48篇 |
2016年 | 65篇 |
2015年 | 48篇 |
2014年 | 98篇 |
2013年 | 92篇 |
2012年 | 121篇 |
2011年 | 141篇 |
2010年 | 83篇 |
2009年 | 67篇 |
2008年 | 55篇 |
2007年 | 89篇 |
2006年 | 91篇 |
2005年 | 62篇 |
2004年 | 61篇 |
2003年 | 71篇 |
2002年 | 48篇 |
2001年 | 49篇 |
2000年 | 20篇 |
1999年 | 27篇 |
1998年 | 25篇 |
1997年 | 27篇 |
1996年 | 17篇 |
1995年 | 12篇 |
1994年 | 12篇 |
1993年 | 20篇 |
1992年 | 14篇 |
1991年 | 14篇 |
1990年 | 11篇 |
1989年 | 14篇 |
1988年 | 3篇 |
1987年 | 9篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1980年 | 3篇 |
排序方式: 共有1923条查询结果,搜索用时 475 毫秒
51.
The operating conditions for the autohydrolysis of eucalyptus wood were optimized with a view to maximizing hemicellulose extraction while preserving the integrity of glucan. The influence of the operating conditions used in the soda–anthraquinone pulping of the solid phase resulting from the autohydrolysis process was examined. Autohydrolysis of the raw material at a liquid/solid ratio of 8 kg water/kg material at 180°C for 30 min was found to provide a commercially useful liquid phase containing most of the starting hemicellulose. The autohydrolysis treatment allowed the subsequent production of soda–anthraquinone cellulose pulp and paper with properties as good as or even better than those obtained without the pretreatment. 相似文献
52.
53.
54.
T.-K. Kim Y.-K. Lee Y.S. Park 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(6):767-775
The aim of this study was to investigate the possible effects of cooking or handling conditions on the concentration of furan in processed foods. The analytical method used to analyse furan levels in foods was optimized based on solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). In baby soups, the concentration of furan decreased by up to 22% after opening a lid for 10 min. In the baby food in retort packaging, the level of furan was reduced by 15–33% after heating the foods at 50°C without a lid. Furan in rice seasonings was evaporated completely after heating the foods at 60°C. Regarding powered milk, the levels of furan were too low to be compared under various conditions. The levels of furan decreased to 58% in beverage products for babies, after storing them at 4°C for 1 day without a lid. The levels of furan in canned foods such as cereal and vegetable were reduced by zero to 52% when they were stored without stirring in a refrigerator at 4°C for 1 day. When we boiled canned fish, the furan present was almost completely evaporated. It is recommended that canned meats be heated up to 50–70°C for the reduction (26–46%) of furan levels. The levels of furan in instant and brewed coffee samples were significantly reduced after storing for 11 to 20 min at room temperature without a lid (p < 0.05). 相似文献
55.
刘涛 《扬州大学烹饪学报》2001,18(4):23-27
菜点质量是餐饮企业都重视的问题。菜点质量的控制是厨房生产过程中的重要环节。菜点质量的优劣不仅取决于原料质量、菜点加工过程的规范化程度,还取决于厨师的技术水平和员工队伍的素质,更重要的是取决于餐饮企业如何对厨房及相关部门实施有效的全面的质量管理。 相似文献
56.
The Han Nguyen Reiko Nagasaka Toshiaki Ohshima 《International Journal of Food Science & Technology》2012,47(6):1193-1205
Edible mushrooms contain considerable amounts of the potent natural antioxidant 2‐thiol‐l ‐histidine‐betaine (l ‐ergothioneine, ESH). The objective of this study was to evaluate the effects of extraction solvents, common cooking methods and storage conditions on the ESH content, total phenols (TPs) and antioxidant capacity of the edible mushroom Flammulina velutipes fruiting body and its hot water extract that had been stored at different temperatures. Regarding cooking procedures, boiling in water resulted in the highest losses of antioxidant activity of both ESH and TPs. Most of the losses of ESH and TPs were detected in the cooking water. The ESH contents in the raw mushroom fruiting bodies significantly decreased after 8 days of refrigerated storage under both dark and fluorescent lighting conditions. However, the TP content in the raw mushroom stored under fluorescent lighting significantly increased during 10 days of refrigeration. In contrast, the ESH and TP contents as well as DPPH radical scavenging ability of the fruiting bodies remained unchanged for up to 15 days of frozen storage at ?18 °C. The same behaviour was obtained with the mushroom extract packed in plastic tubes. The correlation between DPPH radical scavenging activity and ESH contents was higher than that for TP compounds. 相似文献
57.
本文研究了蒽醌(AQ)及其衍生物以及氢化蒽醌对麦草烧碱法蒸煮的作用,用微型计算机处理蒸煮结果,得到7个关于添加剂用量与蒸煮效果关系的数学模型,并对蒸煮过程进行了分析。研究结果表明,氢化蒽醌是比较适合麦草制浆的蒸煮添加剂。 相似文献
58.
本文从丝胶的园二色光谱分析,发现干茧经触蒸后丝胶的性质发生了改变,即茧层丝胶的分子构象由无规卷曲向β—折叠结构转化,指出丝胶变性是茧层丝胶胶着力趋于均匀,为提高生丝净度成绩的关键之一. 相似文献
59.
本文首先对红麻及麦草的化学组分进行了分析,通过亚铵法对红麻、麦草浆配抄挂面牛皮箱纸板的蒸煮、打浆抄片工艺进行了实验研究。结果表明:以红麻和麦草为原料采用亚铵法制浆可以抄造出符合部颁标准的挂面牛皮箱纸板。 相似文献
60.
费万春 《苏州大学学报(工科版)》1989,(3)
本文利用微型电子计算机技术,建立了煮熟茧动态粘弹性的计算机自动检测系统,在不同的煮茧工艺条件下,对解舒优劣不同的两种原料煮熟茧的动态粘弹性进行了检测分析,得到了较为可靠的数据。指出了有关文章所采用的煮熟茧动态粘弹性参数的一些问题,并提出了合理选用参数的方法。得出的一些结论,对于完善煮茧理论、评定煮熟程度、鉴别茧质优劣、改进煮茧工艺、提高生产效益,具有一定的实际意义。 相似文献