全文获取类型
收费全文 | 205篇 |
免费 | 8篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 22篇 |
金属工艺 | 1篇 |
机械仪表 | 4篇 |
建筑科学 | 10篇 |
能源动力 | 3篇 |
轻工业 | 9篇 |
水利工程 | 3篇 |
无线电 | 42篇 |
一般工业技术 | 27篇 |
冶金工业 | 62篇 |
原子能技术 | 3篇 |
自动化技术 | 19篇 |
出版年
2024年 | 1篇 |
2022年 | 4篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 4篇 |
2016年 | 10篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 9篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 4篇 |
2005年 | 10篇 |
2004年 | 4篇 |
2003年 | 11篇 |
2002年 | 6篇 |
2001年 | 7篇 |
2000年 | 7篇 |
1999年 | 3篇 |
1998年 | 25篇 |
1997年 | 13篇 |
1996年 | 8篇 |
1995年 | 8篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有213条查询结果,搜索用时 15 毫秒
21.
K. Kamei M. Yonemura K. Hanafusa 《Journal of Materials Science: Materials in Electronics》2001,12(10):569-574
Co-Al-O film was fabricated using the reactive r.f. magnetron sputtering technique. A maximum magnetoresistance (MR) of approximately 7% was established through optimizing the sputter deposition conditions such as sputter power and gas flow rate. TEM characterization of the film revealed a nano-granular structure that consisted of ferromagnetic grains with grain diameters on the order of several nm together with non-magnetic grain boundary layers with the thickness on the order of less than 1 nm. The large MR was attributed to electron tunneling thorough this very thin grain boundary layer between individual ferromagnetic grains. 相似文献
22.
Paolo Mele Hiroyuki Kamei Hiroyuki Yasumune Kaname Matsumoto Koji Miyazaki 《Metals and Materials International》2014,20(2):389-397
Ca3Co4O9 (p-type) and Zn0.98Al0.02O (n-type) pellets were prepared by conventional sintering (CS) and Spark Plasma sintering (SPS) starting from the oxides. The best p-type sample was SPS Ca3Co4O9 obtained from pre-sintered pellets, with electrical conductivity σ = 144 S/cm and Seebeck coefficient S = 172 μV/K at 800 °C, while thermal conductivity κ = 2.00 W/m×K and figure of merit ZT = 0.23. The best n-type sample was CS Zn0.98Al0.02O showing σ = 83 S/cm and S = ?268 μV/K at 800 °C, while = 5.03 W/m×K and ZT = 0.127. The output power of a module based on SPS Ca3Co4O9 and CS Zn0.98Al0.02O legs was 2.26 mW (with T = 500 °C, ΔT = 248 °C). 相似文献
23.
Kamei S. Inoue Y. Mizuno T. Shibata T. Kaneko A. Takahashi H. Iemura K. 《Electronics letters》2005,41(9):544-546
A silica-based 1.5%-/spl Delta/ 100 GHz-spacing 32-channel athermal arrayed-waveguide grating (AWG) with compact size and extremely low insertion loss is described. By reducing the fibre coupling loss and the excess loss in a silicone-filled groove, an insertion loss of 1.3 dB was achieved with this athermal AWG. 相似文献
24.
Terui H. Shibazaki T. Ebisawa F. Okuno M. Jinnouchi Y. Kamei S. 《Photonics Technology Letters, IEEE》2009,21(19):1426-1428
In this letter, we have developed a novel technique for improving the temperature stability of an athermal silica-based arrayed-waveguide grating with a resin-filled groove. We compensated for the residual second-order temperature dependence of the passband wavelength using the pressure-induced refractive index change in a resin inserted into the optical paths. Pressure control under the temperature variation was achieved by using a structure composed of an optical fiber piston and bimetal actuators. We demonstrated that the passband wavelength variation was successfully reduced from 0.080 to 0.025 nm in a -40degC - 85degC temperature range, without any insertion loss increase or spectral change. 相似文献
25.
Hara T. Fukuda K. Kanazawa K. Shibata N. Hosono K. Maejima H. Nakagawa M. Abe T. Kojima M. Fujiu M. Takeuchi Y. Amemiya K. Morooka M. Kamei T. Nasu H. Chi-Ming Wang Sakurai K. Tokiwa N. Waki H. Maruyama T. Yoshikawa S. Higashitani M. Pham T.D. Yupin Fong Watanabe T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):161-169
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration. 相似文献
26.
S Endo K Inada T Kasai S Koike Y Kamei Y Yamada G Wakabayashi M Yoshida Y Yanagiya 《Canadian Metallurgical Quarterly》1997,95(1):109-112
The mixture of 5'-guanylylimidodiphosphate (Gpp(NH)p)/EDTA/NaCl has been used to delineate low-affinity conditions for agonists binding to G-protein-linked receptors. The effects of this mixture on [3H]RX821002 (2-methoxyidazoxan) binding to alpha2-adrenoceptors were evaluated in different tissues. The density of alpha2-adrenoceptors in the presence of the mixture was 11, 78 and 60% higher in human cortex (predominant alpha2A), human caudate (alpha2A + alpha2C) and rat kidney (alpha2A + alpha2B), respectively, than in its absence. In rat kidney, masking of alpha2B-adrenoceptors by ARC239 (2-[2-[4-(o-methoxyphenyl)-piperazin-1-yl]-ethyl]-4,4-dimethyl-1,3 -(2H,4H)-isoquinolindione) (50 nM) or masking of alpha2A-adrenoceptors by BRL44408 (2-[2H-(1-methyl-1,3-dihydroisoindole)methyl]-4,5-dihydroimidaz ole) (100 nM) demonstrated that the increase was in the alpha2B-adrenoceptor but not in the alpha2A-adrenoceptor subtype. 相似文献
27.
Shikano H. Ito M. Onouchi M. Todaka T. Tsunoda T. Kodama T. Uchiyama K. Odaka T. Kamei T. Nagahama E. Kusaoke M. Nitta Y. Wada Y. Kimura K. Kasahara H. 《Solid-State Circuits, IEEE Journal of》2008,43(4):902-910
This paper describes a heterogeneous multi-core processor (HMCP) architecture that integrates general-purpose processors (CPUs) and accelerators (ACCs) to achieve exceptional performance as well as low-power consumption for the SoCs of embedded systems. The memory architectures of CPUs and ACCs were unified to improve programming and compiling efficiency. Advanced audio codec-low complexity (AAC-LC) stereo audio encoding was parallelized on a heterogeneous multi-core having homogeneous processor cores and dynamically reconfigurable processor (DRP) ACC cores in a preliminary evaluation of the HMCP architecture. The performance evaluation revealed that 54times AAC encoding was achieved on the chip with two CPUs at 600 MHz and two DRPs at 300 MHz, which achieved encoding of an entire CD within 1- 2 min. 相似文献
28.
Shoji Seki Mami Iwasaki Hiroto Makino Yasuhito Yahara Miho Kondo Katsuhiko Kamei Hayato Futakawa Makiko Nogami Kenta Watanabe Nguyen Tran Canh Tung Tatsuro Hirokawa Mamiko Tsuji Yoshiharu Kawaguchi 《International journal of molecular sciences》2022,23(9)
The role of the ligamentum flavum (LF) in the pathogenesis of adolescent idiopathic scoliosis (AIS) is not well understood. Using magnetic resonance imaging (MRI), we investigated the degrees of LF hypertrophy in 18 patients without scoliosis and on the convex and concave sides of the apex of the curvature in 22 patients with AIS. Next, gene expression was compared among neutral vertebral LF and LF on the convex and concave sides of the apex of the curvature in patients with AIS. Histological and microarray analyses of the LF were compared among neutral vertebrae (control) and the LF on the apex of the curvatures. The mean area of LF in the without scoliosis, apical concave, and convex with scoliosis groups was 10.5, 13.5, and 20.3 mm2, respectively. There were significant differences among the three groups (p < 0.05). Histological analysis showed that the ratio of fibers (Collagen/Elastic) was significantly increased on the convex side compared to the concave side (p < 0.05). Microarray analysis showed that ERC2 and MAFB showed significantly increased gene expression on the convex side compared with those of the concave side and the neutral vertebral LF cells. These genes were significantly associated with increased expression of collagen by LF cells (p < 0.05). LF hypertrophy was identified in scoliosis patients, and the convex side was significantly more hypertrophic than that of the concave side. ERC2 and MAFB genes were associated with LF hypertrophy in patients with AIS. These phenomena are likely to be associated with the progression of scoliosis. 相似文献
29.
The microstructure of InxGa1−xAs/GaAs (5 nm/5 nm, x < 0 to 1.0), as grown by a metalorganic chemical vapor deposition two-step growth technique on Si(100)
at 450‡C, and subsequently annealed at 750‡C, is investigated using plan-view and cross-sectional transmission electron microscopy.
The variations in resultant island morphology and strain as a function of the In content were examined through the comparison
of the misfit dislocation arrays and moirés observed. The results are discussed in relation to the ways in which the island
relaxation process changes for high In content. 相似文献
30.
An optical receiver, in which a GaInAs PIN photodiode, an AlInAs/GaInAs HEMT high impedance amplifier and even an equaliser were integrated monolithically on an InP substrate, has been fabricated. An optical sensitivity of -30.4 dBm was obtained at 1.2 Gbit/s and 1.3 mu m wavelength.<> 相似文献