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We compared thermoregulatory responses during night sleep between two kinds of pillow. One has special cool medium consisting of sodium sulfate and ceramic fiber (pillow A) and the other polyester padding (pillow B). The subjects wore 100% cotton thin pajamas with short sleeves and three-quarters trousers for summer use. They lay and slept in bed with cotton sleeping mat and cotton quilt between 10:30 p.m. and 6:30 a.m. in a bed room with an ambient temperature (Ta) of 27 +/- 1 degrees C and a relative humidity of 55 +/- 5%, using either of the pillow A or pillow B. When they awoke, the subjects filled out a questionnaire on how well they slept during sleep. Main results were: 1) Rectal and forehead skin temperatures and heart rate were kept significantly lower in the pillow A during the latter half of the night sleep. 2) Palm and thigh skin temperatures were significantly higher mostly in the pillow A. 3) All the subjects regarded the pillow A better for deeper sleep. It was concluded that slight cooling of the head due to the pillow A during night sleep seemed to be of significance for deep sleep. 相似文献
74.
The H1 NMR measurement was carried out to investigate an electronic property of (BEDT-TTF)(TCNQ). There exist two magnetically different proton sites which belong to BEDT-TTF sheets and TCNQ columns. A distinct peak of 1/T1 appears at TN = 3 K associated with the antiferromagnetic order, which coincides with the results suggested from the anisotropic susceptibility measurement. Any anomaly has not been identified at 35 K, below which a magnetic order was reported to occur in BEDT-TTF sheets. 相似文献
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Yoji Koike Shuichi Takeuchi Hidetaka Sato Yuichiro Hama Masatsune Kato Yasuhiro Ono Susumu Katano 《Journal of Low Temperature Physics》1996,105(3-4):317-322
The effects of substitution of Y or Bi on the low-temperature structural phase transition, electronic anomaly and superconductivity have been studied in La2-y-xYyBaxCuO La2-y-xBiyBaxCuO4 and La1.9-y-xTb0.1BiySrxCuO4 with x = 1/8. Moreover, an electronic anomaly, which is analogous to those observed in La2–xBaxCuO4 and La1.6-xNd0.4SrxCuO4 with x 1/8, has been found below about 60 K in the thermoelectric power measurements for the Zn-substituted La2–xSrxCu1–yZnyO4 with x 0.115 and y = 0.01 – 0.02. These experimental results support the conclusions by Tranquada et al. that static order of the stripe correlations of holes and spins, owing to pinning by the low-temperature structure or impurities (Zn in this case), is the origin of the electronic anomaly, leading to the suppression of superconductivity. 相似文献
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Nitish Mathur Fehmi S. Yasin Matthew J. Stolt Takuro Nagai Koji Kimoto Haifeng Du Mingliang Tian Yoshinori Tokura Xiuzhen Yu Song Jin 《Advanced functional materials》2021,31(13):2008521
In bulk chiral crystals, 3D structures of magnetic skyrmions form topologically protected skyrmion strings (SkS) that have shown potential as magnonic nano-waveguides for information transfer. Although SkS stability is expected to be enhanced in nanostructures of skyrmion-hosting materials, experimental observation and detection of SkS in nanostructures under an applied in-plane magnetic field is difficult. Here, temperature-dependent magnetic field-driven creation and annihilation of SkS in B20 FeGe nanostructures (nanowires and nanoplates) under in-plane magnetic field (H||) are shown and the mechanisms behind these transformations are explained. Unusual asymmetric and hysteretic magnetoresistance (MR) features are observed but previously unexplained during magnetic phase transitions within the SkS stability regime when H|| is along the nanostructure's long edge, which increase the sensitivity of MR detection. Lorentz transmission electron microscopy of the SkS and other magnetic textures under H|| in corroboration with the analysis of the anisotropic MR responses elucidates the field-driven creation and annihilation processes of SkS responsible for such hysteretic MR features and reveals an unexplored stability regime in nanostructures. 相似文献
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Atsushi Yabe Yuichiro Hamate Motoaki Hara Hiroyuki Oguchi Sumito Nagasawa Hiroki Kuwano 《Microfluidics and nanofluidics》2014,16(4):701-710
This paper presents an innovative versatile method aiming at rapid fabrication of a master for polydimethylsiloxane (PDMS) molding. This technology is relying on liquid dielectrophoresis electromechanical microfluidic transduction for programmable ultraviolet (UV) glue manipulation. It enables formation of the master in a tailor-made approach, avoiding the need of micromachined structures unlike in conventional methods. The principle is simple: UV glue, while in liquid phase, is actuated onto an array of electrodes patterned on a Si substrate and cured afterward by UV exposure. The silicon chip and the glue microstructures defined atop of it then play the role of a master for PDMS molding. The glue microstructures’ shape is hemispherical which is of high interest for many microfluidic applications. This concept is assessed and validated with two different PDMS chip replica designs, both of them illustrating representative applications in continuous microfluidic: a T-junction design for inflow droplet generation and a “Quake” type valve. Lastly, this protocol has shown to be recyclable since the UV glue microstructures once formed can be easily removed by immersion in an acetone bath, such as the chip is reset and can be reprogrammed afterward to build another glue channels geometry. 相似文献
79.
Hiroaki Tsuchiya Toshifumi Akaki Daisuke Terada Yuichiro Koizumi Patrik Schmuki Shinji Fujimoto 《Electrochimica acta》2009,54(22):5155-8801
The present work reports how metallurgical factors such as grain size and chemical composition of substrate affect the current behavior during anodization and the morphology of resulting formed oxide layers. The grain size of pure Ti sheet is controlled by the accumulative roll-bonding (ARB) process. Tubular oxide layers are formed on the ARB-processed Ti sheets with different grain sizes, but grain size does not affect the length, diameter of tubes and the degree of tube arrangement. The effect of chemical composition is examined using Ti-Zr alloys (Ti-20Zr, Ti-50Zr, Ti-80Zr) that can consist of a single phase, meaning that homogeneous tube formation can be achieved. With increasing Zr content in the alloys, tube diameter decreases while tube length increases. For the Ti-50Zr and Ti-80Zr, self-organization is achieved on two size scales, that is, nanotube arrays with two distinct diameters are observed. TEM observation revealed that anodic oxide layers are in crystalline state only in the case of pure Zr. 相似文献
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