全文获取类型
收费全文 | 830篇 |
免费 | 34篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 43篇 |
化学工业 | 292篇 |
金属工艺 | 18篇 |
机械仪表 | 18篇 |
建筑科学 | 14篇 |
能源动力 | 57篇 |
轻工业 | 78篇 |
水利工程 | 4篇 |
石油天然气 | 2篇 |
无线电 | 43篇 |
一般工业技术 | 167篇 |
冶金工业 | 24篇 |
原子能技术 | 32篇 |
自动化技术 | 75篇 |
出版年
2024年 | 2篇 |
2023年 | 10篇 |
2022年 | 35篇 |
2021年 | 33篇 |
2020年 | 17篇 |
2019年 | 25篇 |
2018年 | 27篇 |
2017年 | 27篇 |
2016年 | 35篇 |
2015年 | 19篇 |
2014年 | 49篇 |
2013年 | 73篇 |
2012年 | 67篇 |
2011年 | 60篇 |
2010年 | 49篇 |
2009年 | 51篇 |
2008年 | 54篇 |
2007年 | 37篇 |
2006年 | 34篇 |
2005年 | 25篇 |
2004年 | 21篇 |
2003年 | 27篇 |
2002年 | 17篇 |
2001年 | 10篇 |
2000年 | 10篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 10篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有867条查询结果,搜索用时 11 毫秒
11.
Takuya Niikawa Chika Hagino Eri Nishi Ryosuke Kawachi Kotaro Minato Yoshinobu Takada 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(2):190-196
To clarify the motor function of the infant tongue during sucking, we developed an artificial nipple that contained multiple small built‐in force sensors integrated with a PC‐based system which is capable of measuring tongue–artificial nipple contact pressures in real time. The force sensor is a cantilever structure with a small, thin stainless steel beam where an all‐purpose foil strain gauge is attached to the surface of the beam. An artificial nipple made of an elastomer containing these sensors is connected through an amplifier and an A/D converter to a PC via a USB port. Using this system, measurements were taken in three infants whose oral feeding was well established and in one infant of low birth weight. The results from each force sensor showed a pressure waveform of a nearly simple harmonic motion that indicated a peristalsis‐like movement of the tongue; the sucking frequency was found to be about two times per second. In addition, in the low‐birth‐weight infant, the pressure changed as the infant grew. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
12.
Effect of silver content on thermal fatigue life of Sn-xAg-0.5Cu flip-chip interconnects 总被引:5,自引:0,他引:5
Shinichi Terashima Yoshiharu Kariya Takuya Hosoi Masamoto Tanaka 《Journal of Electronic Materials》2003,32(12):1527-1533
The thermal fatigue properties of Sn-xAg-0.5Cu (x=1, 2, 3, and 4 in mass%) flip-chip interconnects were investigated to study
the effect of silver content on thermal fatigue endurance. The solder joints with lower silver context (x=1 and 2) had a greater
failure rate compared to those with higher silver content (x=3 and 4) in thermal fatigue testing. Cracks developed in the
solders near the solder/chip interface for all joints tested. This crack propagation may be mainly governed by the nature
of the solders themselves because the strain-concentrated area was similar for tested alloys independent of the silver content.
From the microstructural observation, the fracture was a mixed mode, transgranular and intergranular, independent of the silver
content. Higher silver content alloys (x=3 and 4) had finer Sn grains before thermal cycling according to the dispersion of
the Ag3Sn intermetallic compound, and even after the cycling, they suppressed microstructural coarsening, which degrades the fatigue
resistance. The fatigue endurance of the solder joints was strongly correlated to the silver content, and solder joints with
higher silver content had better fatigue resistance. 相似文献
13.
Hiroki Uehara Takuya Tamura Masaki Kakiage Takeshi Yamanobe 《Advanced functional materials》2012,22(10):2048-2057
Crystalline homopolymers, including polyethylene (PE), which has the simplest architecture, form a nanometer‐sized combination of crystalline and amorphous components, but their arrangement control, similar to self‐assembled phase‐separation of block‐copolymers, is usually difficult. However, molecular entanglements trapped between crystalline and amorphous components of homopolymers coincide with the segmental linking points on the interfaces of the microphase separation for block copolymers. Nanowrinkled PE membranes are prepared with a network of 30 nm‐thick homogeneous lamellae using a novel entanglement control technique composed of biaxial melt‐drawing and melt‐shrinking procedures, which are limited for highly entangled ultrahigh molecular weight materials. Such a network arrangement of nanowrinkling lamellae spreading on membrane surface and also across the membrane thickness improves the mechanical properties of both tensile strength and tearing strength. Subsequent cold‐drawing causes delamination of the lamellar interfaces, leading to the resultant nanoporous morphology composed of passing‐through channels that are several tens of nanometers in diameter, without any solvent processing. 相似文献
14.
Si photonics becomes one of the research focuses in the field of photonics.Si-based light-emitting devices are one of the most important devices in this field.In this paper,we review the Si-based light... 相似文献
15.
Hiroshi Fujimoto Takuya Miyayama Noriaki Sanada Chihaya Adachi 《Organic Electronics》2013,14(11):2994-2999
We fabricate aluminum cathodes that are almost free from plasma damage by DC magnetron sputtering for organic light-emitting diodes (OLEDs). While sputtering is widely known to have numerous advantages over conventional evaporation for mass production of devices, it can cause serious damage to organic layers. In this report, we fabricate devices that are free from plasma damage by introducing a 1%-Li-doped electron transport layer (ETL). The difference of external electroluminescence quantum efficiency between OLEDs with the structure ITO/α-NPD/ETL/Al (where ITO is indium tin oxide and α-NPD is N,N′-di(1-naphthyl)-N,N′-diphenylbenzidine) with Al cathodes deposited by conventional evaporation or sputtering is 0.1%, and their driving voltage is identical. We find that the Li-doped ETL should be thicker than 40 nm. Analysis of the depth profile of the ETL by time-of-flight secondary ion mass spectrometry indicates that considerable damage from sputtering extended to a depth of approximately 30 nm, suggesting that high-energy particles penetrated about 30 nm into the ETL. 相似文献
16.
Seiya Suzuki Takuya Iwasaki K. Kanishka H. De Silva Shigeru Suehara Kenji Watanabe Takashi Taniguchi Satoshi Moriyama Masamichi Yoshimura Takashi Aizawa Tomonobu Nakayama 《Advanced functional materials》2021,31(5):2007038
Germanene, a 2D honeycomb germanium crystal, is grown at graphene/Ag(111) and hexagonal boron nitride (h-BN)/Ag(111) interfaces by segregating germanium atoms. A simple annealing process in N2 or H2/Ar at ambient pressure leads to the formation of germanene, indicating that an ultrahigh-vacuum condition is not necessary. The grown germanene is stable in air and uniform over the entire area covered with a van der Waals (vdW) material. As an important finding, it is necessary to use a vdW material as a cap layer for the present germanene growth method since the use of an Al2O3 cap layer results in no germanene formation. The present study also proves that Raman spectroscopy in air is a powerful tool for characterizing germanene at the interfaces, which is concluded by multiple analyses including first-principles density functional theory calculations. The direct growth of h-BN-capped germanene on Ag(111), which is demonstrated in the present study, is considered to be a promising technique for the fabrication of future germanene-based electronic devices. 相似文献
17.
Shin-ichi Shimakawa Yasuhiro Hashimoto Shigeo Hayashi Takuya Satoh Takayuki Negami 《Solar Energy Materials & Solar Cells》2008,92(9):1086-1090
Annealed Zn1−xMgxO/Cu(In,Ga)Se2 (CIGS) interfaces have been characterized by ultraviolet light excited time-resolved photoluminescence (TRPL). The TRPL lifetime of the Zn1−xMgxO/CIGS film increased on increasing the annealing temperature to 250 °C, whereas the TRPL lifetime of the CdS/CIGS film had little change by annealing at temperatures lower than 200 °C. This is attributed to the recovery of physical damages by annealing, induced by sputtering of the Zn1−xMgxO film. The TRPL lifetime abruptly decreased with annealing at 300 °C. The diffusion of excess Zn from the Zn1−xMgxO film into the CIGS interface is clearly observed in secondary ion mass spectroscopy (SIMS) depth profiles. These results indicate that excess Zn at the vicinity of the CIGS surface acts as non-radiative centers at the interface. The TRPL lifetime of the Zn1−xMgxO/CIGS film annealed at 250 °C reached values to be comparable to that of the as-deposited CdS/CIGS film. Performance of the Zn1−xMgxO/CIGS cells varied with the annealing temperature in the same manner as the TRPL lifetime. The highest efficiency of the Zn1−xMgxO/CIGS solar cells was achieved for annealing at 250 °C. The results of the TRPL lifetime on annealing show that the cell efficiency is strongly influenced by the Zn1−xMgxO/CIGS interface states related to the damages and diffusion of Zn. 相似文献
18.
Atsushi Watarai Keigo Kubota Masaki Yamagata Takuya Goto Toshiyuki Nohira Rika Hagiwara Koichi Ui Naoaki Kumagai 《Journal of power sources》2008,183(2):724-729
The physicochemical properties of molten alkali bis(trifluoromethylsulfonyl)amide, MTFSI (M = Li, K, Cs), mixture (xLiTFSI = 0.20, xKTFSI = 0.10, xCsTFSI = 0.70) were studied to develop a new rechargeable lithium battery operating at intermediate temperature (100–180 °C). The viscosity and ionic conductivity of this melt at 150 °C are 87.2 cP and 14.2 mS cm−1, respectively. The cyclic voltammetry revealed that the electrochemical window at 150 °C is as wide as 5.0 V, and that the electrochemical deposition/dissolution of lithium metal occurs at the cathode limit. A Li/MTFSI (M = Li, K, Cs)/LiFePO4 cell showed an excellent cycle performance at a constant current rate of C/10 at 150 °C; 95% of the initial discharge capacity was maintained after 50 cycles. Except for the initial few cycles, the coulombic efficiencies were approximately 100% for all the cycles, indicating the stabilities of the molten MTFSI mixture and all the electrode materials. 相似文献
19.
20.
Vaibhav Gupta Swagato Sarkar Olha Aftenieva Takuya Tsuda Labeesh Kumar Daniel Schletz Johannes Schultz Anton Kiriy Andreas Fery Nicolas Vogel Tobias A. F. König 《Advanced functional materials》2021,31(36):2105054
Imprint lithography has emerged as a reliable, reproducible, and rapid method for patterning colloidal nanostructures. As a promising alternative to top-down lithographic approaches, the fabrication of nanodevices has thus become effective and straightforward. In this study, a fusion of interference lithography (IL) and nanosphere imprint lithography on various target substrates ranging from carbon film on transmission electron microscope grid to inorganic and dopable polymer semiconductor is reported. 1D plasmonic photonic crystals are printed with 75% yield on the centimeter scale using colloidal ink and an IL-produced polydimethylsiloxane stamp. Atomically smooth facet, single-crystalline, and monodisperse colloidal building blocks of gold (Au) nanoparticles are used to print 1D plasmonic grating on top of a titanium dioxide (TiO2) slab waveguide, producing waveguide-plasmon polariton modes with superior 10 nm spectral line-width. Plasmon-induced hot electrons are confirmed via two-terminal current measurements with increased photoresponsivity under guiding conditions. The fabricated hybrid structure with Au/TiO2 heterojunction enhances photocatalytic processes like degradation of methyl orange (MO) dye molecules using the generated hot electrons. This simple colloidal printing technique demonstrated on silicon, glass, Au film, and naphthalenediimide polymer thus marks an important milestone for large-scale implementation in optoelectronic devices. 相似文献