全文获取类型
收费全文 | 289篇 |
免费 | 26篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 1篇 |
综合类 | 2篇 |
化学工业 | 61篇 |
金属工艺 | 1篇 |
机械仪表 | 14篇 |
建筑科学 | 2篇 |
能源动力 | 11篇 |
轻工业 | 92篇 |
水利工程 | 2篇 |
无线电 | 42篇 |
一般工业技术 | 45篇 |
冶金工业 | 5篇 |
原子能技术 | 2篇 |
自动化技术 | 36篇 |
出版年
2024年 | 2篇 |
2023年 | 14篇 |
2022年 | 21篇 |
2021年 | 26篇 |
2020年 | 14篇 |
2019年 | 21篇 |
2018年 | 19篇 |
2017年 | 16篇 |
2016年 | 9篇 |
2015年 | 14篇 |
2014年 | 17篇 |
2013年 | 27篇 |
2012年 | 17篇 |
2011年 | 18篇 |
2010年 | 7篇 |
2009年 | 10篇 |
2008年 | 6篇 |
2007年 | 19篇 |
2006年 | 10篇 |
2005年 | 1篇 |
2004年 | 6篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有316条查询结果,搜索用时 15 毫秒
41.
Aims to provide the block architecture of CoStar3400 DSP that is a high performance, low power and scalable VLIW DSP core, it efficiently deployed a variable-length execution set (VLES) execution model which utilizes the maximum parallelism by allowing multiple address generations and data arithmetic logic units to execute multiple instructions in a single clock cycle. The scalability was provided mainly in using more or less number of functional units according to the intended application. Low power support was added by careful architectural design techniques such as fine-grain clock gating and activation of only the required number of control signals at each stage of the pipeline. The said features of the core make it a suitable candidate for many SoC configurations, especially for compute intensive applications such as wire-line and wireless communications, including infrastructure and subscriber communications. The embedded system designers can efficiently use the scalability and VLIW features of the core by scaling the number of execution units according to specific needs of the application to effectively reduce the power consumption, chip area and time to market the intended final product. 相似文献
42.
Faryal Khan Faisal Qayyum Waqas Asghar Muhammad Azeem Zeeshan Anjum Ali Nasir Masood Shah 《Journal of Mechanical Science and Technology》2017,31(11):5265-5272
Carbon fiber reinforced aluminum laminates (CARALL) are one of the aluminum based Fiber metal laminates (FMLs) which, due to their high strength to weight ratio and good impact resistance are greatly replacing aluminum alloys in aircraft structures. In this research work, interlaminate shear strength of Vacuum assisted resin transfer molding (VARTM) manufactured CARALL has been investigated. Numerical simulation model incorporated with real time material data has been developed to predict the delamination behavior of CARALL laminates. Standard CARALL specimens with different surface morphologies were prepared by electric discharge machining, mechanical, chemical and electrochemical surface treatments. T-peel tests were carried out according to standard ASTM D1876-08 to find out inter laminate shear strength. FMLs made out of mechanically, chemically and electrochemically cleaned metal sheets depicted high interlaminate shear strength. SEM micrographs of failed surfaces verify the high adhesive strength of epoxy. Developed numerical simulation model accurately predicts the delamination behavior of CARALL as observed during experimentation. 相似文献
43.
Zubair Butt Riffat Asim Pasha Faisal Qayyum Zeeshan Anjum Nasir Ahmad Hassan Elahi 《Journal of Mechanical Science and Technology》2016,30(8):3553-3558
Energy harvesting is the process of attaining energy from the external sources and transforming it into usable electrical energy. An analytical model of piezoelectric energy harvester has been developed to determine the output voltage across an electrical circuit when it is forced to undergo a base excitation. This model gives an easy approach to design and investigate the behavior of piezoelectric material. Numerical simulations have been carried out to determine the effect of frequency and loading on a Lead zirconate titanate (PZT-5A) piezoelectric material. It has been observed that the output voltage from the harvester increases when loading increases whereas its resonance frequency decreases. The analytical results were found to be in good agreement with the experimental and numerical simulation results. 相似文献
44.
45.
Faqir M Anjum George L Lookhart Charles E Walker 《Journal of the science of food and agriculture》2000,80(2):219-225
Eleven Pakistani hard white spring wheat cultivars, along with one durum wheat and two hard white American‐grown wheat cultivars, were evaluated for their high‐molecular‐weight (HMW) glutenin subunit composition via sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE). The relationships among different quality characteristics and between these characteristics and HMW glutenin subunits were computed. Three to six HMW glutenin subunits were observed in Pakistani bread wheat cultivars. The presence of HMW glutenin subunits was not affected by growth locations or crop years. However, variations in intensities were observed. Correlations were noticed between certain HMW glutenin subunits and some quality attributes, such as protein, farinograph dough development time, farinograph water absorption, loaf volume and mixograph peak height. The presence of HMW glutenin subunit 20 in the older wheat cultivars C591 and C273, known for excellent chapati quality, indicated a possible relationship between this band and chapati quality. This observation will need to be confirmed by testing a larger number of wheat samples known to have characteristics for both good and poor chapati quality. © 2000 Society of Chemical Industry 相似文献
46.
N.J. Salman Ahmed Irfan Anjum Badruddin Jeevan Kanesan Z.A. Zainal K.S. Nazim Ahamed 《International Journal of Heat and Mass Transfer》2011,54(17-18):3822-3825
The present study deals with numerical investigation of effects of different parameters on enhancement or retardation of the heat transfer rate in an annular vertical cylinder filled with saturated porous medium. The heat transfer is assumed to take place by mixed convection mode. The thermal non-equilibrium approach is considered. The inner surface of the annular cylinder is maintained at constant wall temperature whereas the outer surface remains at ambient temperature. The governing partial differential equations are solved using finite element method. The results are discussed for the effects of Peclet number, interphase heat transfer co-efficient and thermal conductivity ratio. 相似文献
47.
Sewing thread is one of the most important components of a sewn product that contributes significantly in the useful life of a product. Stitch class 504 is the one which is used in all types of sewn products. Its thread consumption is higher than class 300 and class 400. A mathematical model to predict the sewing thread consumption of stitch class 504 has been proposed in this paper. The model is based on the geometry of the stitch. The proposed model takes into account material thickness and stitch density. The model was validated by using 24 samples (with different material thickness and stitch densities). The accuracy of the model was found to be 99%. Sensitivity analysis revealed that stitch density has 62% effect and material thickness has 38% effect on thread consumption. The proposed model can predict the thread consumption accurately; therefore, it can be used for better estimation of required thread and encourage its better utilization in sewn product industry. 相似文献
48.
竹原纤维的分级提取及其性能 总被引:1,自引:0,他引:1
为探究不同竹龄及不同取材部位竹原纤维性能的变异规律,以不同竹龄、不同部位的慈竹为原料,采用物理化学结合的方法提取竹原纤维,并分别测定竹原纤维的化学组成、纤维的表面形貌、纤维的密度、吸湿性能、拉伸强度。结果表明:相同部位竹原纤维,随竹龄的增加,纤维的密度先增大后减小,纤维的回潮率先减小后增大;相同竹龄竹原纤维,随着距地高度的增加,纤维密度增加,回潮率先稍有降低后升高。3年生慈竹梢部纤维密度最大,为1.70 /cm3,4年生的基部纤维密度最小,为1.51 g/cm3。3年生慈竹中部纤维回潮率最低,为12.94%,其不同部位竹原纤维拉伸强度较为稳定,4年生中部竹原纤维拉伸强度最大,为787.42MPa。 相似文献
49.
Antioxidant and Antiproliferative Activity of Walnut Extract (Juglans regia L.) Processed by Different Methods and Identification of Compounds Using GC/MS and LC/MS Technique
下载免费PDF全文
![点击此处可从《Journal of Food Processing and Preservation》网站下载免费的PDF全文](/ch/ext_images/free.gif)
50.
Ahmad I Ali Sheraz M Ahmed S Shad Z Vaid FH 《International journal of cosmetic science》2012,34(3):240-245
This study involves the evaluation of the effect of certain stabilizers, that is, citric acid (CT), tartaric acid (TA) and boric acid (BA) on the degradation of ascorbic acid (AH(2) ) in oil-in-water cream formulations exposed to the UV light and stored in the dark. The apparent first-order rate constants (0.34-0.95 × 10(-3) min(-1) in light, 0.38-1.24 × 10(-2) day(-1) in dark) for the degradation reactions in the presence of the stabilizers have been determined. These rate constants have been used to derive the second-order rate constants (0.26-1.45 × 10(-2) M(-1) min(-1) in light, 3.75-8.50 × 10(-3) M(-1) day(-1) in dark) for the interaction of AH(2) and the individual stabilizers. These stabilizers are effective in causing the inhibition of the rate of degradation of AH(2) both in the light and in the dark. The inhibitory effect of the stabilizers is in the order of CT > TA > BA. The rate of degradation of AH(2) in the presence of these stabilizers in the light is about 120 times higher than that in the dark. This could be explained on the basis of the deactivation of AH(2) -excited triplet state by CT and TA and by the inhibition of AH(2) degradation through complex formation with BA. AH(2) leads to the formation of dehydroascorbic acid (A) by chemical and photooxidation in cream formulations. 相似文献