全文获取类型
收费全文 | 105篇 |
免费 | 9篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 33篇 |
金属工艺 | 6篇 |
机械仪表 | 7篇 |
矿业工程 | 1篇 |
能源动力 | 2篇 |
轻工业 | 7篇 |
无线电 | 18篇 |
一般工业技术 | 17篇 |
冶金工业 | 15篇 |
原子能技术 | 1篇 |
自动化技术 | 3篇 |
出版年
2022年 | 3篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 8篇 |
2015年 | 2篇 |
2014年 | 7篇 |
2013年 | 8篇 |
2012年 | 4篇 |
2011年 | 2篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 5篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 7篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1987年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有114条查询结果,搜索用时 218 毫秒
71.
An La0.8Sr0.2MnO3 (LSM)/Sr0.88Y0.08TiO3 (SYT) dual layer interconnect was coated on an NiO-YSZ porous support via screen printing and co-firing processes. SYT and LSM single phase powders were synthesized by solid state reaction and Pechini method, respectively. The thickness of the dual layer was approximately 200 μm. The LSM/SYT dual layer showed a good gas-tightness and had a uniform microstructure without cracks, delamination or warpage. No atomic inter-diffusion between the dual layer and the NiO-YSZ support was detected, suggesting that SYT is phase compatible with NiO-YSZ. The area specific resistance (ASR) of the LSM/SYT/Ni-YSZ sample was 0.19 Ω cm2 at 800 °C under oxidizing/reducing atmospheres; this value was lower than that of the SYT/Ni-YSZ sample. 相似文献
72.
73.
Jun Lee Sung Wan Son Man Yeong Ha Hyung Rak Kim 《Journal of Mechanical Science and Technology》2014,28(10):4221-4232
We numerically investigated the dynamic behavior of the liquid located between and on top of the structures using the 3D Lattice Bolzmann Method. We considered the effect of the contact angle between the structure and the liquid within the range of 90 to 180 degree, the dimensionless height of the structure between 4 and 8, and the dimensionless height of the liquid between 2 and 9 on the dynamic behavior of the liquid. Depending on the contact angle between the structure and the liquid and the relative heights of the liquid and the structure, the liquid takes the form of a liquid film or a liquid droplet. The bigger the contact angle between the structure surface and the liquid grows, the more the liquid existing between the structures moves to the top of the structure and forms a liquid droplet as time passes by. On the other hand, if the contact angle between the structure surface and the liquid is small, the liquid existing between the structures spreads between other structures and over the bottom of the structure and comes to form a liquid film at last. If the structure height is higher, the liquid is tied up between the structures and maintains the form of a liquid film. However, if the liquid height is higher, the liquid forms the shape of a liquid droplet on top of the structures easily. 相似文献
74.
The present study has been carried out to investigate the coarse-grained heat-affected zone (CGHAZ) microstructure and crack
tip opening displacement (CTOD) toughness of grade StE 355 Ti-microalloyed offshore steels. Three parent plates (40-mm thick)
were studied, two of which had Ti microalloying with either Nb + V or Nb also present. As a third steel, conventional StE
355 steel without Ti addition was welded for comparison purposes. Multipass tandem submerged arc weld (SAW) and manual metal
arc weld (SMAW) welds were produced. Different heat-affected zone (HAZ) microstructures were simulated to ascertain the detrimental
effect of welding on toughness. All HAZ microstructures were examined using optical and electron microscopy. It can be concluded
that Ti addition with appropriate steel processing, which disperses fine TiN precipitates uniformly, with a fine balance of
other microalloying elements and with a Ti/N weight ratio of about 2.2, is beneficial for HAZ properties of StE 355 grade
steel. 相似文献
75.
C Lu C Sheehan JW Rak CA Chambers N Hozumi RS Kerbel 《Canadian Metallurgical Quarterly》1996,2(8):1417-1425
We have previously shown that a majority of human melanoma cell lines derived from early-stage lesions were growth inhibited by exogenous interleukin 6 (IL-6) in vitro, whereas cell lines from advanced-stage lesions were resistant to such IL-6-induced growth inhibition. Among the resistant melanoma cell lines, 50-60% constitutively produced IL-6, which appeared to function as a growth stimulator in vitro, based on the growth-suppressive effects of antisense oligonucleotides to the IL-6 gene. The present study was primarily aimed at evaluating whether endogenous IL-6 also functions in vivo as a growth modulator for IL-6-producing and -nonproducing melanoma cells. To do so, we first introduced an IL-6 expression vector into IL-6-nonproducing human melanoma cells using WM35, an early-stage (radial growth phase) cell line, the growth of which is normally inhibited by IL-6, and WM983A, an advanced-stage cell line, the growth of which in vitro is not affected by exogenous IL-6. None of the IL-6-producing transfectants showed a significant alteration in tumor growth in nude mice. Next, two IL-6-producing melanoma cell lines, both of which were derived from metastases, MeWo and WM9, and which are growth resistant to exogenously added IL-6, were transfected with an antisense IL-6 expression vector. Several transfectant clones manifested a constitutive decrease in IL-6 gene expression and protein production, and they also gave rise to much smaller tumors with slower growth rates and longer latency periods. However, these IL-6 antisense transfectants were not growth suppressed in in vitro cell cultures, relative to their respective parental controls. Taken together, the results demonstrate that endogenous IL-6 can indeed function as a growth stimulator for human cutaneous melanomas in vivo. This growth-stimulatory or survival mechanism remains to be clarified but may be paracrine rather than autocrine in nature. 相似文献
76.
Artificial Plasmid Labeled with 5‐Bromo‐2′‐deoxyuridine: A Universal Molecular System for Strand Break Detection 下载免费PDF全文
Dr. Agnieszka Zylicz‐Stachula Dr. Katarzyna Polska Prof. Piotr Skowron Prof. Janusz Rak 《Chembiochem : a European journal of chemical biology》2014,15(10):1409-1412
DNA strand breaks (SBs) are among the most cytotoxic forms of DNA damage, and their residual levels correlate directly with cell death. Hence, the type and amount of SBs is directly related to the efficacy of a given anticancer therapy. In this study, we describe a molecular tool that can differentiate between single (SSBs) and double (DSBs) strand breaks and also assess them quantitatively. Our method involves PCR amplification of a linear DNA fragment labeled with a sensitizing nucleotide, circularization of that fragment, and enzymatic introduction of supercoils to transform the circular relaxed form of the synthesized plasmid into a supercoiled one. After exposure of the molecule to a damaging factor, SSB and DSB levels can be easily assayed with gel electrophoresis. We applied this method to prepare an artificial plasmid labeled with 5‐bromo‐2′‐deoxyuridine and to assay SBs photoinduced in the synthesized plasmid. 相似文献
77.
Hyung Rak Song Eui Goo Kang Chul Min Bae Choong Yeol Lee Duk Lak Lee Won Jong Nam 《Metals and Materials International》2006,12(3):239-243
The effects of a Cr addition and transformation temperature on the strength and work hardening behavior of cold drawn hyper-eutectoid
steel wires are investigated in this study. The Cr addition was found to be effective for increasing the tensile strength
and work hardening rate,k/(2 λ°)1/2, due to the refinement of the initial interlamellar spacing and the increment of the Hall-Petch parameter. While the work
hardening rate,k/(2 λ°)1/2, was significantly influenced by the magnitude of the interlamellar spacing, the Hall-Petch parameter,k, was not affected by the interlamellar spacing. Additionally, the refinement of the interlamellar spacing due to the low
transformation temperature and the Cr addition caused an increase of the RA in drawn pearlitic steels. 相似文献
78.
Jung Rak Lee Do Geun Kim Gun Hwan Lee Yong Ho Park Pung Keun Song 《Metals and Materials International》2007,13(5):399-402
In−Zn−Sn−O films were deposited on a polycarbonate (PC) substrate by a magnetron co-sputtering system using two cathodes (DC,
RF) without substrate heating. Two types of ITO targets (target A: doped with 5 wt.% SnO2, target B: doped with 10 wt.% SnO2) were used as an In−Sn−O source. The ITO and ZnO targets were sputtered by DC and RF discharges, respectively, and the composition
of the In−Zn−Sn−O films was controlled via the power ratio of each cathode. In the case of ITO target A, the lowest resistivity
(4.3×10−4 Ωcm) was obtained for the film deposited at the RF power (ZnO) of 55W. In the case of ITO target B, the lowest resistivity
(2.9×10−4 Ωcm) of the film was obtained at the RF power (ZnO) of 30W, which was attributed to the increase in carrier density. Hall
mobility decreased with increasing carrier density, which could be explained by the increase in ionized impurity scattering. 相似文献
79.
80.