全文获取类型
收费全文 | 561篇 |
免费 | 117篇 |
国内免费 | 3篇 |
专业分类
综合类 | 21篇 |
化学工业 | 81篇 |
金属工艺 | 3篇 |
建筑科学 | 3篇 |
矿业工程 | 1篇 |
能源动力 | 6篇 |
轻工业 | 542篇 |
水利工程 | 5篇 |
石油天然气 | 4篇 |
无线电 | 1篇 |
一般工业技术 | 11篇 |
冶金工业 | 2篇 |
自动化技术 | 1篇 |
出版年
2024年 | 9篇 |
2023年 | 32篇 |
2022年 | 44篇 |
2021年 | 52篇 |
2020年 | 33篇 |
2019年 | 37篇 |
2018年 | 30篇 |
2017年 | 38篇 |
2016年 | 40篇 |
2015年 | 42篇 |
2014年 | 37篇 |
2013年 | 34篇 |
2012年 | 48篇 |
2011年 | 40篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 13篇 |
2007年 | 26篇 |
2006年 | 19篇 |
2005年 | 23篇 |
2004年 | 12篇 |
2003年 | 10篇 |
2002年 | 7篇 |
2001年 | 5篇 |
2000年 | 7篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有681条查询结果,搜索用时 78 毫秒
1.
2.
3.
Functional and conformational characterisation of walnut protein obtained through AOT reverse micelles 下载免费PDF全文
Haifang Hu Yali Sun Xiaoyan Zhao Di Liu Lidan Fu Haitao Zhu 《International Journal of Food Science & Technology》2015,50(11):2351-2359
Walnut protein was extracted from defatted walnut flour by bis (2‐ethylhexyl) sodium sulfosuccinate (AOT) reverse micellar system and alkali solution with isoelectric precipitation. The functional and conformational characteristics of two proteins were investigated and compared. Walnut protein obtained through AOT reverse micelles was found to have higher extraction yield, solubility, emulsifying activity, foam capacities, water‐ and oil‐holding capacity compared to the protein from alkali solution along with isoelectric precipitation, while the surface hydrophobicity (H0), contents of disulphide bond (SS) and sulfhydryl group (SH) were relatively lower. The differences of H0, SS and SH contents could be due to the conformational changes of walnut proteins using two extraction methods. FTIR spectra and data showed that the reverse micelles caused the decrease in α‐helix, β‐sheet, random and β‐turn of walnut protein, the increase in the side‐chain structure content, which could be responsible for the modification of functional properties. 相似文献
4.
5.
6.
7.
In this paper, under the control strategy of surface charge of BiOCl photocatalyst and the electrostatic adsorption of anions and cations in potassium bromide (KBr) and polyvinylpyrrolidone (PVP), the self-assembly of “walnut-like” BiOCl/Br solid solution nanophotocatalyst at a lower temperature water bath was proposed for the first time. X-ray diffraction (XRD), Raman, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive system (EDS), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), UV-Vis, photoluminescence spectroscopy (PL) and Mott-Schottky curve, transient photocurrent densities, and electrochemical impedance spectroscopy (EIS) were used to analyze the properties of materials, including its morphology, element distribution and chemical states, specific surface area, electrochemical property, and photogenic charge transfer. Based on the degradation performance of RhB dye wastewater and phenol in visible and ultraviolet light, and the band structure of BiOCl/Br solid solution, the reason for the improved photocatalytic activity was deeply discussed, and the possible degradation mechanism was also put forward. The above results show that Br− can be inserted into the crystal lattice of BiOCl under the effect of electrostatic adsorption to form solid solution by the interaction between atomic orbitals, which not only reduces the bandgap width but also improves the separation and mobility of photogenic electrons and holes, causing the absorbed light to shift red to the visible region. In addition, when the nBr−/nCl− = 0.67, “walnut-like” BiOCl/Br solid solution was formed, and this kind of special core-shell structure not only can increase the specific surface area, increase the number of active sites, but also can make the light reflect and refract many times in the cavity and further increase the utilization rate of light energy, and then the best photocatalytic activity was achieved. This study provides an new method to enhance the photocatalytic performance of BiOCl and be conducive to the development of modern material science. 相似文献
8.
探讨不同提取方法对新疆薄皮核桃油酸价和过氧化值的影响。分别采用索氏抽提有机溶剂(石油醚)法、超临界CO_2萃取法、冷榨法提取薄皮核桃油,用容量分析法测定油脂中的酸价和过氧化值,并比较三种方法提取的油脂的氧化稳定性。结果表明,提取方法对核桃油脂的色泽、气味、氧化稳定性影响较大。索氏抽提法操作简便、成本低,但得到的核桃油脂有溶剂残留,需脱溶,且提取时间较长。超临界CO_2萃取精密度可靠,得到的油脂品质和纯度高,但生产成本高。结合实际生产,冷榨法更适合用于核桃油的提取。 相似文献
9.
核桃的营养保健功能及药用价值研究进展 总被引:1,自引:0,他引:1
核桃中所含的有益健康的成分如ω-3系多不饱和脂肪酸、生育酚、抗氧化剂及褪黑素等,对心脏病、动脉硬化、癌症、糖尿病、肥胖等慢性非传染性疾病的预防发挥积极的独到作用.本文就核桃的营养价值、保健功能及对与疾病预防方面的研究进展进行了综述. 相似文献
10.
核桃壳催化热解制取氢气 总被引:1,自引:0,他引:1
利用自制的热解反应炉,选取核桃壳为原料,以MnO2、Al2O3、CaO三种金属氧化物为催化剂进行了一系列催化热解制备氢气的研究。实验中着重对比了催化剂存在情况下,热解气体中的氢气产率、氢气产量随热解温度的变化规律。在此基础上,选取催化剂MnO2、Al2O3和CaO进行了不同使用量对热解实验结果影响的实验。实验结果表明,MnO2的添加量在3%时,对核桃壳热解产气中的氢气体积分数提高有最佳的催化作用。 相似文献