全文获取类型
收费全文 | 1954篇 |
免费 | 213篇 |
国内免费 | 57篇 |
专业分类
电工技术 | 39篇 |
综合类 | 97篇 |
化学工业 | 165篇 |
金属工艺 | 15篇 |
机械仪表 | 24篇 |
建筑科学 | 40篇 |
矿业工程 | 9篇 |
能源动力 | 17篇 |
轻工业 | 1460篇 |
水利工程 | 17篇 |
石油天然气 | 19篇 |
武器工业 | 7篇 |
无线电 | 168篇 |
一般工业技术 | 48篇 |
冶金工业 | 18篇 |
原子能技术 | 12篇 |
自动化技术 | 69篇 |
出版年
2024年 | 21篇 |
2023年 | 39篇 |
2022年 | 59篇 |
2021年 | 76篇 |
2020年 | 94篇 |
2019年 | 86篇 |
2018年 | 62篇 |
2017年 | 65篇 |
2016年 | 95篇 |
2015年 | 79篇 |
2014年 | 79篇 |
2013年 | 121篇 |
2012年 | 151篇 |
2011年 | 133篇 |
2010年 | 97篇 |
2009年 | 73篇 |
2008年 | 80篇 |
2007年 | 108篇 |
2006年 | 108篇 |
2005年 | 88篇 |
2004年 | 78篇 |
2003年 | 62篇 |
2002年 | 66篇 |
2001年 | 54篇 |
2000年 | 24篇 |
1999年 | 38篇 |
1998年 | 32篇 |
1997年 | 17篇 |
1996年 | 12篇 |
1995年 | 16篇 |
1994年 | 16篇 |
1993年 | 11篇 |
1992年 | 7篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 11篇 |
1988年 | 9篇 |
1987年 | 12篇 |
1986年 | 5篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
排序方式: 共有2224条查询结果,搜索用时 15 毫秒
111.
荞麦绿豆蛋白饮料的研制 总被引:1,自引:0,他引:1
以杂粮中的荞麦和绿豆为原料,以感官评定和稳定性为指标,确定出苦荞绿豆奶饮料的生产工艺配方和主要工艺参数,并对饮料中功能性成分芦丁含量进行了测定。 相似文献
112.
玉米赤霉烯酮(zearalenone,ZEN)是目前全球范围污染谷物最广泛的霉菌毒素之一,对人体和动物健康都会产生极大威胁,目前从市售小豆检测到ZEN。【目的】筛选暴露ZEN的小豆内生真菌,结合经典方法和分子生物学方法鉴定所筛选内生真菌,并探索菌株潜在的ZEN产生风险。【方法】以暴露ZEN的小豆为样本,将分离纯化后的内生真菌进行经典形态观察;同时扩增真菌核糖体保守序列ITS1、ITS4,镰刀菌特异基因序列FU1、FU2确定小豆中镰刀菌种属,同时通过ZEN玉米赤霉烯酮产毒控制基因pks13进行PCR扩增,分析菌株ZEN合成的潜在风险。【结果】鉴别出3株镰刀菌,其中2株初步鉴定为砖红镰刀菌(Fusarium lateritium)、1株为花腐镰刀菌(Fusarium napiforme),未检测出ZEN合成关键基因;1株玛利节菱孢霉(Arthrinium marii),分子检测具有产ZEN玉米赤霉烯酮毒素的可能性。将以上4株菌分别回接至ZEN的产毒培养基,LC-MS/MS法未检测出ZEN毒素。【结论】暴露ZEN的小豆具有内生镰刀菌,存在可能产ZEN的内生节菱孢霉;回接培养基未检测到ZEN,但不排除小豆产生ZEN的风险。 相似文献
113.
Identification and evaluation of volatile odor-active pollutants from different odor emission sources in the food industry 总被引:1,自引:0,他引:1
In order to elucidate the nature of different odor-emission sources in the food industry, odor-active pollutants of the exhaust air in the cooling gases from coffee bean roasting, the exhaust air of fish meal production, and the exhaust air of swine breeding were investigated. Knowledge of what pollutants are present in the odor emission and are responsible for the malodor is vital to the development of suitable adsorbers/absorbers and filters, and combinations of the same. Therefore, the objective of these investigations was to identify and evaluate the characteristic impact of compounds in the exhaust air of these odor-emission sources. The volatile compounds were collected by using a microprocessor-controlled gas sampler through sorbent tubes of Tenax TA. The adsorbed compounds were analyzed by thermal desorption into a cryotrap and subsequent gas chromatography separation, followed by simultaneous olfactometry and mass spectrometry. In cooling gases of the coffee bean roasting numerous compounds (up to 100) were identified of which only 22 were important for the characteristic odor. These compounds were aldehydes (2-methyl propanal, 2- and 3-methyl butanal, 2-furancarboxyaldehyde, 5-methyl-2-furancarboxyaldehyde), diketones (2,3-butandione, 2,3-pentandione), pyrazines, pyridine, acetic acid, and furanmethanol. Other compounds with low concentrations but with a very low odor threshold and, therefore, important for the total odor were 3-methyl butanoic acid and guaiacol. Up to 50 compounds were identified in the exhaust air of fish meal production, the most significant of these being trimethylamine. Trimethylamine, with a very low odor threshold (0.0025 g/l air) and the highest content (up to 60% in the total ion chromatogram, more than 100 g/l) in the exhaust air of fish meal production, was responsible for the characteristic fishy odor. Beside trimethylamine only a few compounds, e.g., sulfides (dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide), aldehydes (2-methyl propanal, 2- and 3-methyl butanal), ethanol, and guaiacol, played a secondary role for the total odor. In the exhaust air of the pig house up to 50 compounds were identified. Beside ammonia, the most important odor-active compounds were various carboxylic acids (acetic acid, butanoic acid, 3-methyl butanoic acid), sulfides (dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide), trimethylamine, and the intensive odor-active p-cresol and 4-ethylphenol. 相似文献
114.
115.
Identification and monitoring of metabolite markers of dry bean consumption in parallel human and mouse studies
下载免费PDF全文
![点击此处可从《Molecular nutrition & food research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
116.
超高效液相色谱-串联质谱法测定豆芽中7种药物残留 总被引:1,自引:0,他引:1
建立了甲醇超声提取,分散固相萃取净化技术(QuEChERS)净化,超高效液相色谱-串联三重四极杆质谱(UPLC-MS/MS)检测豆芽中7种药物(咪鲜胺、头孢氨苄、诺氟沙星、6-苄氨基嘌呤、赤霉酸、2,4-二氯苯氧乙酸和4-氯苯氧乙酸)残留的方法。样品用含0.1%甲酸的甲醇溶液超声提取,QuEChERS(PSA+C18)净化,在UPLC-MS/MS的电喷雾正、负离子分段扫描和多反应监测(MRM)模式下检测,以保留时间和特征离子对定性,外标法定量。结果表明,7种待测物在0.4~100 μg/L范围内线性关系良好;方法定量限(S/N=10)为2.0~5.0 μg/kg;添加水平为2.0~50 μg/kg时,平均回收率在80.7%~115%之间;相对标准偏差(RSD,n=6)为2.6%~13.5%。本方法具有前处理简单、结果准确、回收率高等特点,可以应用于豆芽中7种药物残留的日常监测。 相似文献
117.
Martínez-Manrique E Jacinto-Hernández C Garza-García R Campos A Moreno E Bernal-Lugo I 《Journal of the science of food and agriculture》2011,91(13):2394-2398
BACKGROUND: Cooking time decreases when beans are soaked first. However, the molecular basis of this decrease remains unclear. To determine the mechanisms involved, changes in both pectic polysaccharides and cell wall enzymes were monitored during soaking. Two cultivars and one breeding line were studied. RESULTS: Soaking increased the activity of the cell wall enzymes rhamnogalacturonase, galactanase and polygalacturonase. Their activity in the cell wall was detected as changes in chemical composition of pectic polysaccharides. Rhamnose content decreased but galactose and uronic acid contents increased in the polysaccharides of soaked beans. A decrease in the average molecular weight of the pectin fraction was induced during soaking. The decrease in rhamnose and the polygalacturonase activity were associated (r = 0.933, P = 0.01, and r = 0.725, P = 0.01, respectively) with shorter cooking time after soaking. CONCLUSION: Pectic cell wall enzymes are responsible for the changes in rhamnogalacturonan I and polygalacturonan induced during soaking and constitute the biochemical factors that give bean cell walls new polysaccharide arrangements. Rhamnogalacturonan I is dispersed throughout the entire cell wall and interacts with cellulose and hemicellulose fibres, resulting in a higher rate of pectic polysaccharide thermosolubility and, therefore, a shorter cooking time. Copyright © 2011 Society of Chemical Industry 相似文献
118.
119.
在研制出豆渣面包的基础上,比较研究了豆渣面包与普通面包的品质差异。通过控制变量法,对两种面包产品的感官,质构以及风味进行了比较和评价。结果表明,以面粉100%计,加入面粉质量10%的干豆渣、43%的豆浆及10%的黄油时,所得产品品质优良,风味独特;加入豆渣粉的面包感官评分较普通面包好;豆渣面包的硬度、黏结性和咀嚼性比普通面包大,而粘性和弹性却不如普通面包;含豆渣面包与普通面包气味成分差别不显著。 相似文献
120.
Hang Li Liang Zou Xin-Yan Li Ding-Tao Wu Hong-Yan Liu Hua-Bin Li Ren-You Gan 《Comprehensive Reviews in Food Science and Food Safety》2022,21(3):2335-2362
Adzuki bean (Vigna angularis), also called red bean, is a legume of Fabaceae (Leguminosae) family. This crop is native to East Asia and is also commercially available in other parts of the world. It is becoming a research focus owing to its distinct nutritional properties (e.g., abundant in polyphenols). The diverse health benefits and multiple utilization of this pulse are associated with its unique composition. However, there is a paucity of reviews focusing on the nutritional properties and potent applications of adzuki beans. This review summarizes the chemical compositions, physicochemical properties, health benefits, processing, and applications of adzuki beans. Suggestions on how to better utilize the adzuki bean are also provided to facilitate its development as a functional grain. Adzuki bean and its components can be further developed into value-added and nutritionally enhanced products. 相似文献