全文获取类型
收费全文 | 306篇 |
免费 | 21篇 |
国内免费 | 3篇 |
专业分类
综合类 | 18篇 |
化学工业 | 39篇 |
金属工艺 | 1篇 |
轻工业 | 268篇 |
一般工业技术 | 3篇 |
自动化技术 | 1篇 |
出版年
2024年 | 2篇 |
2023年 | 7篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 10篇 |
2014年 | 6篇 |
2013年 | 15篇 |
2012年 | 20篇 |
2011年 | 20篇 |
2010年 | 17篇 |
2009年 | 20篇 |
2008年 | 19篇 |
2007年 | 23篇 |
2006年 | 31篇 |
2005年 | 18篇 |
2004年 | 26篇 |
2003年 | 26篇 |
2002年 | 7篇 |
2001年 | 4篇 |
2000年 | 8篇 |
1998年 | 1篇 |
排序方式: 共有330条查询结果,搜索用时 946 毫秒
11.
利用乙醇/磷酸氢二钾双水相体系浸提大豆异黄酮固体,并采用四因素四水平正交试验,考察了乙醇质量分数、磷酸氢二钾质量分数、温度、时间对大豆异黄酮的分配系数和萃取收率的影响。结果发现,影响大豆异黄酮萃取收率的因素为:时间磷酸氢二钾质量分数乙醇质量分数温度。最佳提取条件为:25%乙醇/25%磷酸氢二钾双水相体系,室温(20℃)浸提30 min。大豆异黄酮几乎全部分配在上相,其上相收率为97.0%。 相似文献
12.
ABSTRACT: Antioxidant properties of genistein were tested during the low temperature oxidation of linseed oil. Four linseed oil solutions were prepared: linseed oil, linseed oil containing 2 μmol added genistein/g oil, linseed oil containing 4 μmol added genistein/g oil, and linseed oil containing 200 ppm butylated hydroxyanisole (BHA). Dimethyl sulfoxide (DMSO) (1.7%) was added to all solutions to allow for the solubilization of genistein. Antioxidant activities were analyzed using 2 techniques: (i) the oven stability test carried out at 60 °C with periodic determination of peroxide values (PV); and (ii) oxidation on a heated (60 °C) FTIR-ATR crystal with periodic scanning and collection of infrared spectra. Induction points (IP) for each solution were determined. A strong correlation ( r = 0.91) was noted between the 2 analytical methods used. Three significantly ( P < 0.10) different levels of IP were generally observed. The shortest IP (17 h for PV, 36.9 h for FTIR) was found for the linseed oil. Intermediate IP's were obtained for the 2 μmol added genistein/g oil (32.4 h for PV, 43.5 h for FTIR) and 4 μmol added genistein/g oil (33.9 h for PV, 44.2 h for FTIR) samples. The longest IP (39.9 h for PV, 54.2 h for FTIR) was obtained for the 200 ppm BHA containing solution. Although genestein was not as effective as BHT in retarding oxidation, the results clearly demonstrate that it is able to act as an antioxidant in a bulk oil system. 相似文献
13.
14.
15.
Okara (residue of the soymilk manufacture) is rich in proteins, fibres and lipids. It also contains isoflavones that possess health‐promoting properties. A new method has been developed for the valorization of fibres from okara by hydrolysis of insoluble proteins with a protease and removal of the oil. Three different processes were investigated: the first one involved delipidation and drying prior to proteolysis and led to the highest content of fibre (80%) in the final product. The second used proteolysis on crude okara followed by solvent delipidation–dehydration and gave an intermediate content of fibre (75%). The last process was totally enzymatic (proteolysis and lipolysis) and gave the lowest content of fibre in the final product (50%). Fibre water‐holding capacity was correlated to the total dietary fibre content of each sample. It was preferable to use crude okara for hydrolysis, since oven‐drying during the process decreased the water‐holding capacity and modified the isoflavone profile of okara. Copyright © 2005 Society of Chemical Industry 相似文献
16.
《分离科学与技术》2012,47(13):3239-3257
Abstract In this paper, the feasibility of recovering the solvent from the aqueous ethanol solution of soybean isoflavones with nanofiltration (NF) was studied. Five commercially available polymeric NF membranes were employed and STARMEM? 122 showed acceptable flux and high retention. The central composite design (CCD) of the response surface methodology (RSM) was applied to model the effects of temperature, pressure, and feed concentration on the permeate flux and the total soybean isoflavone retention. The results indicate that the developed models were in good agreement with the experimental results and they can be used to predict this NF process. 相似文献
17.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(4):627-633
Phytoestrogens are natural components of plants consumed by humans. The hormonal activity of these substances has long been known. Various in vitro tests have demonstrated the agonistic or antagonistic estrogenic activity of some phytoestrogens. The objective of this study was to estimate the supply of isoflavones in the diet of a healthy adult female population and to assess its estrogenic effect. The diet was assessed by questionnaire and the estrogenicity of the estimated isoflavone content was tested by E-screen, finding a mean total estrogenic capacity of 0.129 × 10?10 eq.E2 (12.9 pmol day–1), corresponding to a daily isoflavone intake of 265.8 μg day–1. This study offers a preliminary insight into the phytoestrogen content of the diet of a healthy active population of Spanish women. The effects of this additional hormonal burden are highly controversial, and this approach to estimating dietary phytoestrogen intake of specific populations may help to elucidate its implications for human health. 相似文献
18.
Mitsuo Miyazawa Koji Takahashi Hideo Araki 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(4):674-678
Biotransformation of the isoflavones, 6,7,4′‐trimethoxyisoflavone ( 1 ) and 5,7,4′‐trimethoxyisoflavone ( 2 ) by Aspergillus niger was investigated. Compound 1 was transformed to 4′‐hydroxy‐6,7‐dimethoxyisoflavone ( 3 ) and 2 to 4′‐hydroxy‐5,7‐dimethoxyisoflavone ( 4 ). This suggested that 1 and 2 were demethylated at the C‐4′ position with regioselectivity by Aspergillus niger. Copyright © 2006 Society of Chemical Industry 相似文献
19.
建立简单、快速的HPLC法测定蓝花喜盐鸢尾中一种全新异黄酮糖苷——鸢尾甲黄素B 4'-O-β-D-葡萄糖苷。采用HPLC法,Agilent 1260HC-C18(4.6 mm×250 mm,5μm)色谱柱,流动相为甲醇-1%冰醋酸梯度洗脱,流速为0.9 m L/min,检测波长为268 nm,柱温为25℃。结果表明,该异黄酮糖苷在17.2~172μg/m L浓度内线性关系良好,相关系数为0.999 4;回收率为99.78%(RSD=0.76%)。该检测方法准确灵敏,适用于蓝花喜盐鸢尾中鸢尾甲黄素B 4'-O-β-D-葡萄糖苷的测定。 相似文献
20.
目的 测试食品豆豉和中药淡豆豉样本中的药典成分,分离培养其留存的微生物菌株,分析微生物类别、发酵过程与功能成分的关系。方法 平板筛选培养、菌苔外观和显微镜鉴别微生物菌株,液相色谱法测定大豆异黄酮及苷元成分的含量,纤维平板法测试纤溶酶活性。结果 中药淡豆豉和食品豆豉的微生物以枯草芽孢杆菌最多,其次是霉菌和酵母;样本大豆异黄酮和苷元成分差异较大,有些中药材淡豆豉低于药典标准;个别食品豆豉样本具有纤溶酶活性,中药材淡豆豉少有纤溶酶活性。结论 留存于淡豆豉或豆豉中的微生物丰度顺序如下:枯草芽孢杆菌、霉菌和酵母;大豆异黄酮和苷元成分的含量与发酵过程有关,样本的差异较大;溶栓不是中药材淡豆豉的主要功效。 相似文献