首页 | 官方网站   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   300篇
  免费   11篇
  国内免费   1篇
工业技术   312篇
  2023年   2篇
  2022年   2篇
  2021年   1篇
  2020年   7篇
  2019年   6篇
  2018年   4篇
  2017年   12篇
  2016年   4篇
  2015年   5篇
  2014年   5篇
  2013年   23篇
  2012年   12篇
  2011年   16篇
  2010年   11篇
  2009年   5篇
  2008年   9篇
  2007年   7篇
  2006年   7篇
  2005年   9篇
  2004年   11篇
  2003年   13篇
  2002年   11篇
  2001年   5篇
  2000年   8篇
  1999年   4篇
  1998年   13篇
  1997年   12篇
  1996年   11篇
  1995年   12篇
  1994年   8篇
  1993年   9篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
  1988年   4篇
  1987年   1篇
  1986年   4篇
  1985年   2篇
  1984年   7篇
  1983年   4篇
  1982年   2篇
  1981年   1篇
  1977年   3篇
  1976年   6篇
  1975年   1篇
  1974年   2篇
  1973年   4篇
  1971年   1篇
  1970年   2篇
  1957年   1篇
排序方式: 共有312条查询结果,搜索用时 15 毫秒
1.
ABSTRACT

Fossil fuel resource is on the draining stage which leads to an increment in the cost of the petroleum products. Nowadays, research is focused on the development of environmental friendly lubricants which are derivatives of renewable sources. Inedible plant oil-driven bio-lubricants are environmentally friendly because they are non-hazardous, biodegradable, as well as there is no emission of toxic gases. This study involves the characterisations, advantages, as well as utilisation of inedible plant oil-driven bio-lubricants as an alternative for tribological applications. This report presents the status about the global lubricant market as well as potential outlook. Inedible plant oil-driven bio-lubricants bear high viscosity, high lubricity, and high viscosity index which can enhance the equipment service life and has the ability to carry high load and results in minimum amount of metal traces during combustion.  相似文献   
2.
3.
The extrabulbar olfactory projections (EBOP) is a collection of nerve fibers that originate from primary olfactory receptor neurons. These fibers penetrate into the brain, bypassing the olfactory bulbs (OBs). While the presence of an EBOP has been well established in teleosts, here we morphologically characterize the EBOP structure in four species each with a different morphological relationship of OB with the ventral telencephalic area. Tract‐tracing methods (carbocyanine DiI/DIA and biocytin) were used. FMRFamide immunoreactive nervus terminalis (NT) components were also visualized to define any neuroanatomical relationship between the NT and EBOP. Unilateral DiI/DiA application to the olfactory chamber stained the entire olfactory epithelium, olfactory nerve fibers, and ipsilateral olfactory bulb. Labeled primary olfactory fibers running ventromedially as extrabulbar primary olfactory projections reached various regions of the secondary prosencephalon. Only in Moenkhausia sanctaefilomenae (no olfactory peduncle) did lipophilic tracer‐labeled fibers reach the ipsilateral mesencephalon. The combination of tracing techniques and FMRFamide immunohistochemistry revealed a substantial overlap of the label along the olfactory pathways as well as in the anterior secondary prosencephalon. However, FMRFamide immunoreactivity was never colocalized in the same cellular or fiber component as visualized using tracer molecules. Our results showed a certain uniformity in the neuroanatomy and extension of EBOP in all four species, independent of the pedunculate feature of the OBs. The present study also provided additional evidence to support the view that EBOP and FMRFamide immunoreactive components of the NT are separate anatomical entities. Microsc. Res. Tech. 78:268–276, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
4.
Objective: Innovation in material science has made it possible to fabricate a pharmaceutical material of modifiable characteristics and utility, in delivering therapeutics at a sustained/controlled rate. The objective of this study is to design and optimize the controlled release transdermal films of S-Amlodipine besylate by intercalating hydrophilic and hydrophobic polymers.

Methods: 3(2) factorial design and response surface methodology was utilized to prepare formulations by intercalating the varied concentration of polymers(A) and penetration enhancer(B) in solvent. The effect of these independent factors on drug release and flux was investigated to substantiate the ex-vivo, stability and histological findings of the study.

Results: FTIR, DSC revealed the compatibility of drug with polymers; however, the semicrystallinity in drug was observed under PXRD. SEM micrographs showed homogeneous dispersion and entanglement of drug throughout the matrix. Results from the permeation study suggested the significant effect of factors on the ex vivo permeation of drug. It was observed that drug release was found to be increased with an increase in hydrophilic polymer concentration and PE. The formulations having polymers (EC:PVPK-30) at 7:3 showed maximum drug release with highest flux (102.60?±?1.12?µg/cm2/h) and permeability coefficient (32.78?±?1.38?cm/h). Significant effect of PE on lipid and protein framework of the skin was also observed which is responsible for increased permeation. The optimized formulation was found to be stable and showed no-sign of localized reactions, indicating safety and compatibility with the skin.

Conclusion: Thus, results indicated that the prepared intercalated transdermal matrix can be a promising nonoral carrier to deliver effective amounts of drug.  相似文献   

5.
Abstract

We have shown that the performances available from a two-source relief sensing interferometer are improved substantially by combining an innovative way of managing the phase resources inherent in the interferometer. The approach gives rise to the emergence of a flexible and versatile holographic contouring method capable of addressing surfaces of broadly varying depths. Experimental results are presented to support the proposal.  相似文献   
6.
7.
BACKGROUND: This paper reports on the use of a liquid emulsion membrane involving paraffin light oil as membrane phase and lecithin as surfactant for the extraction of alcohol from anthocyanin extract and simulated pineapple wine. RESULTS: The extraction of alcohol was found to depend on the many factors such as surfactant concentration, contact time, stirring speed, stirring time, and ratio of membrane emulsion to feed volume. Results showed that optimum conditions for maximum alcohol extraction (25%) were lecithin concentration 3%, contact time 20 min, stirring speed 250 rpm and ratio of membrane emulsion to feed volume 1:2. Multistage extraction using this liquid emulsion membrane was found to completely remove alcohol from anthocyanin extract and from simulated pineapple wine in seven stages and five stages, respectively. CONCLUSION: This liquid emulsion membrane was found to be a useful method for the extraction of alcohol from aqueous feed. Copyright © 2009 Society of Chemical Industry  相似文献   
8.
This review discusses the processing techniques proposed for the production of dried and intermediate moisture honey products, as well as their properties. Stickiness is the major problem in the drying of sugar rich products like honey, that depend on the type of sugar and temperature of operation, which are related to the glass transition temperature. Some additives are usually added to the sugary feed to increase the glass transition temperature and concurrently the sticky point temperature. In the case of honey-fruit spreads, nutritional and sensory characteristics can be enhanced by replacing part of sugar with honey. Co-crystallization of honey with sucrose could be used to preserve the honey flavor. These diversified honey products provide better taste and nutrition to the consumer besides enhancing the utilization of honey.  相似文献   
9.
The problem of blood flow through a narrow catheterized artery with an axially nonsymmetrical stenosis has been investigated. Blood is represented by a two-phase macroscopic model, i.e., a suspension of erythrocytes (red cells) in plasma (Newtonian fluid). The coupled differential equations for both fluid (plasma) and particle (erythrocyte) phases have been solved and the expression for the flow characteristics, namely, the flow rate, the impedance (resistance to flow), the wall shear stress and the shear stress at the stenosis throat have been derived. It is found that the impedance increases with the catheter size, the hematocrit and the stenosis size (height and length) but decreases with the shape parameter. A significant increase in the magnitude of the impedance and the wall shear stress occurs even for a small increase in the catheter size. The flow resistance increases and the shear stress at the stenosis throat decreases with the increasing catheter size and assume an asymptotic value at about the catheter size half of the artery size.  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-23

京公网安备 11010802026262号