首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   108篇
  免费   4篇
电工技术   2篇
化学工业   31篇
金属工艺   3篇
机械仪表   3篇
建筑科学   4篇
矿业工程   1篇
能源动力   9篇
轻工业   8篇
水利工程   1篇
无线电   10篇
一般工业技术   17篇
冶金工业   1篇
原子能技术   2篇
自动化技术   20篇
  2022年   3篇
  2021年   5篇
  2020年   6篇
  2019年   3篇
  2018年   7篇
  2017年   6篇
  2016年   8篇
  2015年   6篇
  2014年   3篇
  2013年   16篇
  2012年   3篇
  2011年   2篇
  2010年   8篇
  2009年   6篇
  2008年   3篇
  2007年   6篇
  2006年   3篇
  2005年   5篇
  2004年   1篇
  2003年   3篇
  2001年   2篇
  1999年   2篇
  1998年   1篇
  1996年   1篇
  1992年   1篇
  1983年   2篇
排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
Five labdane diterpenoids, austroinulin, iso-austroinulin, sterebin E, sterebin E acetate, and sterebin A acetate, along with hydrocarbons, aliphatic alcohols, β-amyrin, β-sitosterol and stigmasterol were isolated from the chloroform soluble fraction of the methanol extract of Stevia rebaudiana leaves. Chlorogenic and caffeic acids were isolated from the EtOAc fraction. All the isolated compounds were identified using spectral tools. The chloroform and methanol extracts proved significant anti-inflammatory effect and caused marked inhibition of carrageenan-induced paw oedema in rats.  相似文献   
2.
The influence of processing conditions and interfacial modification on the morphology evolution and the composition range within which fully co‐continuous high density polyethylene/polystyrene blend structures can exist during blending in a single screw extruder was studied. Blends ranging from pure A to pure B component, with and without compatibilizer, were prepared under two different shear rates. It was found that high shear rates displaced the breakdown–coalescence balance of the dispersed nodules to the side of coalescence, narrowing the percolation domain and the critical composition for full co‐continuity decreased with increasing shear rates. The addition of a tri‐block compatibilizer induced the percolation threshold of the polystyrene phase to begin at lower percentages of polyethylene but the phase inversion point did not change. The experimental results are discussed in the light of various theoretical models. Copyright © 2005 Society of Chemical Industry  相似文献   
3.
The corrosion and inhibition behavior of mild steel in 1 M HCl in the presence of poly(4-vinylpyridine)(P4VP) and potassium iodide (KI) was investigated using weight loss measurements, potentiodynamic polarization studies and impedance measurements. The inhibition efficiency increased with increasing P4VP concentration. The inhibiting action of P4VP is considerably enhanced by the addition of potassium iodide. The adsorption of this compound either alone or in combination with iodide ions on the metal surface is found to obey Lamgmir's adsorption isotherm. The experimental results suggest that the presence of iodide ions in the solution increases the surface coverage and, therefore, indicate the joint adsorption of P4VP and iodide ions. On the other hand, it was found that the inhibiting effect of P4VP and (P4VP + KI) increased with increasing temperature of the corrosion medium. The presence of these species in the solution decreases the double layer capacitance and increases the charge transfer resistance, both derived from Nyquist plots obtained from a.c. impedance studies. The variation of charge transfer resistance with time suggests that the inhibitive action of (P4VP + KI) depends mainly on the protective inhibitor film formed on the steel surface.  相似文献   
4.
Multimedia Tools and Applications - Studies of visual attention of patients with Dementia such as Parkinson’s Disease Dementia and Alzheimer Disease is a promising way for non-invasive...  相似文献   
5.
Multi-view video plus depth (MVD) format is considered as the next-generation standard for advanced 3D video systems. MVD consists of multiple color videos with a depth value associated with each texture pixel. Relying on this representation and by using depth-image-based rendering techniques, new viewpoints for multi-view video applications can be generated. However, since MVD is captured from different viewing angles with different cameras, significant illumination and color differences can be observed between views. These color mismatches degrade the performance of view rendering algorithms by introducing visible artifacts leading to a reduced view synthesis quality. To cope with this issue, we propose an effective method for correcting color inconsistencies in MVD. Firstly, to avoid occlusion problems and allow performing correction in the most accurate way, we consider only the overlapping region when calculating the color mapping function. These common regions are determined using a reliable feature matching technique. Also, to maintain the temporal coherence, correction is applied on a temporal sliding window. Experimental results show that the proposed method reduces the color difference between views and improves view rendering process providing high-quality results.  相似文献   
6.
A boronic acid-based anthracene fluorescent probe was functionalised with an acrylamide unit to incorporate into a hydrogel system for monosaccharide detection. In solution, the fluorescent probe displayed a strong fluorescence turn-on response upon exposure to fructose, and an expected trend in apparent binding constants, as judged by a fluorescence response where D-fructose>D-galactose>D-mannose>D-glucose. The hydrogel incorporating the boronic acid monomer demonstrated the ability to detect monosaccharides by fluorescence with the same overall trend as the monomer in solution with the addition of D-fructose resulting in a 10-fold enhancement (≤0.25 mol/L).  相似文献   
7.
8.
The fractionated crystallization of high density polyethylene dispersed in a poly(ethylene terephthalate) matrix at composition of 15 wt-% was studied. The effect of the molecular weight of polyethylene with and without compatibilization was particularly addressed regarding its influence on the morphology of the blends. For non-compatibilized blends, the dramatic influence of the molecular weight of the polyethylene on the viscosity ratio and therefore on the dispersion is reflected on the relative intensities of the twin crystallization peaks of polyethylene that are developed upon cooling. These peaks reflect two sets of particles that are nucleated by more or less active heterogeneities. The influence of the addition of an ethylene-glycidyl methacrylate copolymer on the morphology and on the crystallization of the blends was also investigated. For a high molecular weight polyethylene, the compatibilizer shows less efficiency as far as dispersion is concerned.  相似文献   
9.
Souad Timoumi  Daoued Mihoubi 《LWT》2007,40(9):1648-1654
The goal of this study was to determine the effect of drying temperature on the shrinkage, ascorbic acid (vitamin C) degradation and aroma retention of apples. Apple samples were found to shrink continuously until a water content value of 2 kg/kg d.b. The degradation of ascorbic acid followed a pseudo-first-order reaction and the degradation rate constant increased when temperature increased from 40 to 70 °C. The loss of aroma volatiles increased with temperature and drying time.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号