全文获取类型
收费全文 | 58篇 |
免费 | 18篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 2篇 |
综合类 | 2篇 |
化学工业 | 12篇 |
金属工艺 | 3篇 |
机械仪表 | 2篇 |
建筑科学 | 1篇 |
能源动力 | 5篇 |
轻工业 | 15篇 |
石油天然气 | 4篇 |
无线电 | 18篇 |
一般工业技术 | 6篇 |
冶金工业 | 1篇 |
自动化技术 | 7篇 |
出版年
2023年 | 4篇 |
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 6篇 |
2011年 | 4篇 |
2010年 | 3篇 |
2009年 | 2篇 |
2006年 | 3篇 |
2001年 | 1篇 |
1999年 | 2篇 |
1997年 | 2篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有78条查询结果,搜索用时 15 毫秒
21.
Eulsoo Park Minji Kim Jong‐Shik Shin 《Advanced Synthesis \u0026amp; Catalysis》2010,352(18):3391-3398
A novel biocatalytic process for production of L ‐homoalanine from L ‐threonine has been developed using coupled enzyme reactions consisting of a threonine deaminase (TD) and an ω‐transaminase (ω‐TA). TD catalyzes the dehydration/deamination of L ‐threonine, leading to the generation of 2‐oxobutyrate which is asymmetrically converted to L ‐homoalanine via transamination with benzylamine executed by ω‐TA. To make up the coupled reaction system, we cloned and overexpressed a TD from Escherichia coli and an (S)‐specific ω‐TA from Paracoccus denitrificans. In the coupled reactions, L ‐threonine serves as a precursor of 2‐oxobutyrate for the ω‐TA reaction, eliminating the need for employing the expensive oxo acid as a starting reactant. In contrast to α‐transaminase reactions in which use of amino acids as an exclusive amino donor limits complete conversion, amines are exploited in the ω‐TA reaction and thus maximum conversion could reach 100%. The ω‐TA‐only reaction with 10 mM 2‐oxobutyrate and 20 mM benzylamine resulted in 94% yield of optically pure L ‐homoalanine (ee>99%). However, the ω‐TA‐only reaction did not produce any detectable amount of L ‐homoalanine from 10 mM L ‐threonine and 20 mM benzylamine, whereas the ω‐TA reaction coupled with TD led to 91% conversion of L ‐threonine to L ‐homoalanine. 相似文献
22.
For characterization or optimization process, a computer prediction model is in demand. A new technique, to improve the prediction performance of conventional generalized regression neural network (GRNN) of plasma process data was presented. Genetic algorithm (GA) was applied to optimize multi-parameterized training factors of GRNN. To evaluate the technique, two data sets were collected from the etchings of silica and silicon carbide (SiC) thin films in inductively coupled plasmas. Both data sets called Data I and Data II were statistically characterized by means of 23 and 24 full factorial experiment plus one center point. The GRNN models trained with these data were tested with additional six and 16 experiments. A total of eight etch outputs were modeled and compared with conventional GRNN and statistical regression models. The five etch outputs comprising Data I include silica etch rate, aluminum (Al) etch rate, Al selectivity, profile angle, and DC bias. Data II consisted of three etch outputs, including SiC etch rate, surface roughness, and profile angle. Compared to GRNN models, GA-GRNN models yielded more than 40% and 15% improvements for all etch outputs comprising Data I and Data II, respectively. Similar improvements were also demonstrated with respect to statistical regression models. All these results reveal that a multi-parameterization of training factors and GA optimization is an effective technique to considerably improve the prediction performance of conventional GRNN model. 相似文献
23.
24.
Woo Minji Kim Mijeong Noh Jeong Sook Park Chan Hum Song Yeong Ok 《Food science and biotechnology》2018,27(1):211-218
Food Science and Biotechnology - This study investigated the effect of kimchi on hepatic lipid metabolism and inflammatory response. Low-density lipoprotein receptor knockout mice fed high... 相似文献
25.
26.
采用羧甲基纤维素钠(CMC-Na)与纳米二氧化钛(nano-TiO2)2种材料进行复合,通过研究复合膜的性能,找出较合适的二氧化钛含量,用于咸水鸭蛋的涂膜保鲜研究。结果表明羧甲基纤维素钠膜中添加适量纳米二氧化钛能增强其抗张强度,降低水蒸气透过率和溶胀性能,添加4%nano-TiO2的复合膜的综合性能较好。以CMCNa/4%nano-TiO2的溶液涂膜咸水鸭蛋,考察其对蛋贮藏期间失重率、蛋清pH、蛋黄指数、哈夫单位、菌落总数等新鲜度指标的影响,发现不经涂膜的空白组贮藏到21 d时,已不适宜消费者食用,而CMC-Na/nano-TiO2涂膜组到42 d时,还在可食用范围内,不添加nano-TiO2的CMC-Na涂膜组可以将鸭蛋保鲜至35 d。所以CMC-Na涂膜可以延长咸水鸭蛋的贮藏期,添加nano-TiO2的涂膜组比未添加的效果更好。 相似文献
27.
Minji Lee Jeong-Yong Cho Yu Geon Lee Hyoung Jae Lee Seong-Il Lim So-Young Lee Young-Do Nam Jae-Hak Moon 《Food science and biotechnology》2016,25(5):1259-1264
Eleven compounds, including a new sesquiterpene, were isolated from the culture medium of Aspergillus oryzae incubated with capsaicin. The structure of the new compound was determined to be 1,3,5a,6,7,8,9,9a-octahydro-9-hydroxy-9-(hydroxymethyl)-6-isopropyl-1-oxobenzo[c]oxepine-4- carboxylic acid, a heptelidic acid derivative. In addition, 10 known compounds were identified, namely 5-(hydroxymethyl)-3-furancarboxylic acid (flufuran), 3-hydroxypropanoic acid, 5-(hydroxymethyl)-2- furancarboxylic acid, 2-(4-hydroxyphenyl)-ethanol, 4-hydroxybenzoic acid, vanillic acid, 3,4-dihydroxybenzoic acid, 2-furanol, hydroheptelidic acid, and trichoderonic acid A, using spectroscopic data from nuclear magnetic resonance and electrospray ionization–mass spectroscopy. 相似文献
28.
29.
本文以储能集装箱为研究对象,根据锂电池发热特性,应用标准k-湍流模型、D-O辐射模型,实现了集装箱内流场、温度场的数值模拟。对基准工况与优化工况进行了相关数值模拟,基准工况模拟结果表明:距离空调近端与远端出风均匀性存在较大差别,存在电池模块间温差较大情况。通过在风道内加设导流板,并进行结构调整,对原有工况进行优化,优化工况模拟结果表明:优化后流场与温度场分布更加均匀,能够有效降低电池模块间温差。 相似文献
30.
Minji Kim Enuji Choi Jinseon Kim Hyunwoo Ahn Hojong Han Wang June Kim 《Journal of the Institute of Brewing》2016,122(3):422-429
Beer is generally considered to be a beverage that has high microbiological stability. However, some undesirable lactic acid bacteria (LAB) can grow in beer and consequently spoil this beverage. In this study, bacteriocin‐producing Pediococcus acidilactici K10 was used as a means of bio‐acidifying the mash and reducing the spoilage LAB content of the beer. The K10 strain had antimicrobial activity against two beer spoilage LAB strains in wort and did not grow in a beer environment. The K10 strain was inoculated before the mashing step. The effect of K10 as a starter culture was investigated and compared with a control. As a result, filtration time was shortened by 17 min, alcohol content was increased by 137%, foam stability was increased by 156%, bitterness was increased by two bitterness units and there was a significant difference (p < 0.05) in aromatic and sour odour. The feasibility of using bacteriocin‐producing LAB strain in beer brewing is envisaged. Copyright © 2016 The Institute of Brewing & Distilling 相似文献