全文获取类型
收费全文 | 75篇 |
免费 | 1篇 |
专业分类
化学工业 | 15篇 |
金属工艺 | 2篇 |
机械仪表 | 4篇 |
建筑科学 | 2篇 |
能源动力 | 12篇 |
轻工业 | 3篇 |
无线电 | 12篇 |
一般工业技术 | 9篇 |
冶金工业 | 7篇 |
自动化技术 | 10篇 |
出版年
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 9篇 |
2012年 | 6篇 |
2011年 | 12篇 |
2010年 | 8篇 |
2009年 | 6篇 |
2008年 | 3篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2004年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1994年 | 4篇 |
1980年 | 1篇 |
排序方式: 共有76条查询结果,搜索用时 31 毫秒
11.
Forging limits in a discontinuously reinforced aluminum (DRA) matrix composite, 2014 Al/15 vol pct A1-2O-3, were determined by compressing samples of various cylindrical geometries under different conditions of temperature, strain
rate, and lubrication and measuring the limit strains attained prior to incipient crack formation. In some cases, circumferential
grids were machined on the sample surface to obtain the local fracture strain states. Crack formation was caused by the secondary
tensile stresses; however, crack propagation was relatively slow and somewhat more severe at 300 °C than at 400 °C. The forging
limit of the composite was found to be higher at 400 °C than at 300 °C and also higher at slower strain rates. The plane-strain
forging limit of the composite at 300 °C and a strain rate of 0.5 s”1 was less than 0.05, while that of the matrix was higher
than 0.5. It was found that the forging limits can be influenced by the depth of the circumferential grids and can be lower
than those for the smooth surface samples.
Formerly Graduate Student, the University of Michigan 相似文献
12.
C. K. Chung Y. J. Syu H. Y. Wang C. C. Cheng S. L. Lin K. Z. Tu 《Microsystem Technologies》2013,19(3):439-443
The liquid crystal display (LCD) needs the back light module (BLM) for the light source. The light guide plate (LGP) is the main component of BLM to spread light source to the whole LCD surface and requires for the generation trend of lightweight, easy to carry, and bendable for LCD. In this article, we have demonstrated the fabrication of flexible LGP using CO2 laser LIGA-like technology which includes the laser ablation of micro-groove polymethylmethacrylate (PMMA) master mold, pouring polydimethylsiloxane (PDMS) to the mold and casting the micro-groove microstructure for flexible LGP application. Different laser powers and micro-groove pitches were used to ablate the PMMA mold with varied groove depths and taper angles. Optical microscope was used to examine the morphology and profile of the final bendable LGP microstructure. Under the varied laser power of 1–12 W, the mean taper angles of PMMA micro-grooves ranged from 28° to 70° and the etching depths were from 44.5 to 281.8 μm. The flexible PDMS LGP had good microstructure duplication after casting. The optical uniformity and luminance of flexible LGP was concerned with structure of micro-grooves and measured using BM9 luminance meter. The maximal light uniformity and average luminance of LGP at some microstructure reaches 75 % and 119 cd/m2, respectively. 相似文献
13.
Sun Jerry Chih-Yuan Syu Yun-Ru Lin Yu-Yan 《Universal Access in the Information Society》2017,16(2):273-288
Universal Access in the Information Society - The objective of this study is to enhance our understanding of whether learners’ conformity behaviors and learning anxiety can affect their... 相似文献
14.
Nandho Rahmansyah Chieh‐Tsung Lo Ciou‐Mei Syu Chien‐Liang Lee 《Polymer International》2011,60(9):1380-1389
The non‐isothermal crystallization of poly(ethylene oxide) (PEO)/silver nanoplate composites was studied using differential scanning calorimetry. The non‐isothermal crystallization was analyzed by combining the Avrami and Ozawa equations. It was found that the Avrami exponent for neat PEO ranges from 2.51 to 2.53, whereas it ranges from 2.54 to 3.16 for its composites, indicating that the spherical crystal morphology does not change with the addition of nanoplates. However, the rate determination of crystal growth transfers from diffusion to nucleation. The crystallization half‐time showed an increase with the addition of silver nanoplates in PEO, indicating that the overall crystallization rate of PEO decreases with the addition of nanoplates. However, the nucleation activity is larger than unity in the composites and the value increases with an increase in the nanoplate content. This behavior implies that the nanoplates act as anti‐nucleating agents to hinder nucleation. Copyright © 2011 Society of Chemical Industry 相似文献
15.
Tong-Bou Chang Siou-Ci Syu Yen-Kai Yang 《International Journal of Heat and Mass Transfer》2012,55(4):1014-1021
An experimental investigation is conducted into the effects of the particle volume fraction on the spray heat transfer performance of a nanofluid comprising de-ionized water and Al2O3 particles with a diameter of 35 nm. The tests are performed with a flat, horizontal heated surface using a nozzle with an orifice diameter of 0.7 mm and a nozzle-to-heated surface distance of 17 mm. The spray mass flux is varied in the range of 26.433–176.751 kg/m2 s, while the particle volume fraction is specified as 0%, 0.001%, 0.025%, or 0.05%. It is found that the optimal heat transfer performance is obtained using a particle volume fraction of 0.001%. The surface compositions of the sprayed samples are observed using scanning electron microscopy. The results show that the surfaces sprayed with a nanofluid containing 0.025 Vol% or 0.05 Vol% of nanoparticles contain a small amount of Al. However, those cooled using a nanofluid with a particle volume fraction of 0% or 0.001% show no traces of Al. 相似文献
16.
Hydrogen production via the water gas shift reaction (WGSR) was investigated in a high gravity environment. A rotating packed bed (RPB) reactor containing a Cu–Zn catalyst and spinning in the range of 0–1800 rpm was used to create high centrifugal force. The reaction temperature and the steam/CO ratio ranged from 250 to 350 °C and 2 to 8, respectively. A dimensionless parameter, the G number, was derived to account for the effect of centrifugal force on the enhancement of the WGSR. With the rotor speed of 1800 rpm, the induced centrifugal force acting on the reactants was as high as 234 g on average in the RPB. As a result, the CO conversion from the WGSR was increased up to 70% compared to that without rotation. This clearly revealed that the centrifugal force was conducive to hydrogen production, resulting from intensifying mass transfer and elongating the path of the reactants in the catalyst bed. From Le Chatelier’s principle, a higher reaction temperature or a lower steam/CO ratio disfavors CO conversion; however, under such a situation the enhancement of the centrifugal force on hydrogen production from the WGSR tended to become more significant. Accordingly, a correlation between the enhancement of CO conversion and the G number was established. As a whole, the higher the reaction temperature and the lower the steam/CO ratio, the higher the exponent of the G number function and the better the centrifugal force on the WGSR. 相似文献
17.
Improved Photodynamic Cancer Treatment by Folate‐Conjugated Polymeric Micelles in a KB Xenografted Animal Model
下载免费PDF全文
![点击此处可从《Small (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
18.
Jin-Siang Syu Chinchun Meng 《Microwave and Wireless Components Letters, IEEE》2007,17(12):876-878
A 2.4/5.7 GHz dual-band Gilbert upconversion mixer is demonstrated using 0.35 mum SiGe BiCMOS technology. A bias-offset cross-coupled transconductance amplifier (TCA) is employed in the intermediate frequency port for the linearity improvement. The dual-band LC current combiner and the output shunt-shunt feedback buffer amplifier are in the radio frequency (RF) port. The mechanisms of the high linearity upconverter and the design flow of the dual-band LC current combiner are established in this letter. The dual-band upconverter has conversion gain of 1.5/-0.2 dB, OP1dB, and of -10.5/-9 dBm, and OIP3 of 12/13 dBm for IF=100 MHz, RF 2.4/5.7 GHz, respectively. 相似文献
19.
20.
Based on the three-dimensional (3D) piezoelectricity, we presented asymptotic solutions for multilayered piezoelectric hollow cylinders using the method of perturbation. The material properties in the general formulation are firstly regarded to be heterogeneous through the thickness, and then specified as the layerwise step functions in the cases of multilayered cylinders. The transverse normal load and normal electric displacement are respectively applied on the lateral surfaces of the cylinders. The boundary conditions of cylinders are considered to be simply supported at the two edges. In the formulation the twenty-two basic equations of piezoelectricity are reduced to eight differential equations in terms of eight primary variables of elastic and electric fields. After performing nondimensionalization, asymptotic expansion and successive integration, we finally decompose the 3D problem into a series of 2D problems with the same governing equations for various orders except for the nonhomogeneous terms. In view of the recurrent property, it is illustrated that the present asymptotic solutions can be obtained in a hierarchic manner and asymptotically approach 3D piezoelectricity solutions. 相似文献