全文获取类型
收费全文 | 207篇 |
免费 | 21篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 56篇 |
金属工艺 | 13篇 |
机械仪表 | 8篇 |
建筑科学 | 9篇 |
能源动力 | 15篇 |
轻工业 | 19篇 |
水利工程 | 3篇 |
石油天然气 | 2篇 |
无线电 | 19篇 |
一般工业技术 | 40篇 |
冶金工业 | 7篇 |
原子能技术 | 1篇 |
自动化技术 | 36篇 |
出版年
2023年 | 5篇 |
2022年 | 7篇 |
2021年 | 7篇 |
2020年 | 9篇 |
2019年 | 10篇 |
2018年 | 16篇 |
2017年 | 8篇 |
2016年 | 18篇 |
2015年 | 14篇 |
2014年 | 13篇 |
2013年 | 23篇 |
2012年 | 16篇 |
2011年 | 19篇 |
2010年 | 10篇 |
2009年 | 16篇 |
2008年 | 15篇 |
2007年 | 7篇 |
2006年 | 3篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1996年 | 1篇 |
1983年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有229条查询结果,搜索用时 31 毫秒
21.
22.
Joost Van Aelst Danny Verboekend An Philippaerts Nicolas Nuttens Mert Kurttepeli Elena Gobechiya Mohamed Haouas Sreeprasanth P. Sree Joeri F. M. Denayer Johan A. Martens Christine E. A. Kirschhock Francis Taulelle Sara Bals Gino V. Baron Pierre A. Jacobs Bert F. Sels 《Advanced functional materials》2015,25(46):7130-7144
Hierarchical zeolites are a class of superior catalysts which couples the intrinsic zeolitic properties to enhanced accessibility and intracrystalline mass transport to and from the active sites. The design of hierarchical USY (Ultra‐Stable Y) catalysts is achieved using a sustainable postsynthetic room temperature treatment with mildly alkaline NH4OH (0.02 m ) solutions. Starting from a commercial dealuminated USY zeolite (Si/Al = 47), a hierarchical material is obtained by selective and tuneable creation of interconnected and accessible small mesopores (2–6 nm). In addition, the treatment immediately yields the NH4+ form without the need for additional ion exchange. After NH4OH modification, the crystal morphology is retained, whereas the microporosity and relative crystallinity are decreased. The gradual formation of dense amorphous phases throughout the crystal without significant framework atom leaching rationalizes the very high material yields (>90%). The superior catalytic performance of the developed hierarchical zeolites is demonstrated in the acid‐catalyzed isomerization of α‐pinene and the metal‐catalyzed conjugation of safflower oil. Significant improvements in activity and selectivity are attained, as well as a lowered susceptibility to deactivation. The catalytic performance is intimately related to the introduced mesopores, hence enhanced mass transport capacity, and the retained intrinsic zeolitic properties. 相似文献
23.
Hierarchical Zeolite: Catalyst Design by NH4OH Treatment of USY Zeolite (Adv. Funct. Mater. 46/2015)
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Joost Van Aelst Danny Verboekend An Philippaerts Nicolas Nuttens Mert Kurttepeli Elena Gobechiya Mohamed Haouas Sreeprasanth P. Sree Joeri F. M. Denayer Johan A. Martens Christine E. A. Kirschhock Francis Taulelle Sara Bals Gino V. Baron Pierre A. Jacobs Bert F. Sels 《Advanced functional materials》2015,25(46):7244-7244
24.
25.
26.
HJ Merté 《Canadian Metallurgical Quarterly》1976,94(9):467-469
All glaucomatous eye damages are caused by a too high intra-ocular pressure. This damage of the eye nerve leads in chronical cases from a slowly increasing loss of the visual field, which is usually not noticed by the patient, to total blindness. Prophylactic examinations should be introduced to all persons over 40 years old. The examination should consist of the measurement of the intra-ocular pressure and should be carried out within a period of 3-5 years. 相似文献
27.
The performance of a trickle bed reactor is investigated by the moment technique. Residence time distributions of SO2 tracer in both gas (Helium) and liquid (distilled water) effluents are used to predict zero reduced and first absolute moments and these values are compared with the derived theoretical expressions. Correlations are suggested for gas-liquid mass transfer coefficient, liquid hold up, and extent of axial mixing in liquid phase.True adsorption equilibrium constant of the system is estimated as 0.378 from liquid full bed experiments and contacting efficiency of the trickle bed reactor is found as 0.987.Effect of axial dispersion is not significant on gas-liquid mass transfer coefficient since absorption factor is small, but is found to be quite important on the true estimation of adsorption factor. 相似文献
28.
Anne Mette Frey Selcuk Mert Johannes Due-Hansen Rasmus Fehrmann Claus Hviid Christensen 《Catalysis Letters》2009,128(1-2):1-8
Iron-containing zeolites are known to be promising catalysts for the NH3-SCR reaction. Here, we will investigate the catalytic activity of iron-based BEA catalysts, which was found to exhibit improved activities compared to previously described iron-containing zeolite catalysts, such as ZSM-5 and ZSM-12. Series of Fe-BEA zeolite catalysts were prepared using a range of different preparation methods. Furthermore, we found that an iron concentration around 3 wt% on BEA showed a small optimum in SCR activity compared to the other iron loadings studied. 相似文献
29.
30.
Hatice Hande Mert 《国际能源研究杂志》2020,44(8):6583-6594
A novel shape-stabilized n-hexadecane/polyHIPE composite phase change material (PCM) was designed and thermal energy storage properties were determined. Porous carbon-based frameworks were produced by polymerization of styrene-based high internal phase emulsions (HIPEs) in existence of the surface modified montmorillonite nanoclay. The morphological and mechanical properties of the obtained polyHIPEs were investigated by scanning electron microscopy analysis and the compression test, respectively. The polyHIPE composite with the best pore morphology and the highest compression modulus was determined as a framework to prepare the form stable n-hexadecane/polyHIPE composite phase change material using the one-step impregnation method. The chemical structure and morphologic property of composite PCM was investigated by FT-IR and polarized optical microscopy analysis. Thermal stability of the form-stable PCM (FSPCM) was examined by TG analysis. The n-hexadecane fraction engaged into the carbon foam skeleton was found of as 55 wt% from TG curve. differential scanning calorimetry analysis was used for determining melting temperature and latent heat storage capacity of FSPCM and these values were determined as (26.36°C) and (143.41 J/g), respectively. The results indicated that the obtained composite material (FSPCM) has a considerable potential for low temperature (18°C-30°C) thermal energy storage applications with its thermal energy storage capacity, appropriate phase change temperatures and high thermal stability. 相似文献