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排序方式: 共有1283条查询结果,搜索用时 15 毫秒
1.
2.
Juichiro Arai Katsuhiro Kojima Nobuhide Mori 《Journal of Low Temperature Physics》1996,105(3-4):455-460
Fe3+-ESR measurements are carried out for the samples of (La1–xSrx)2Cu1–yFeyO4–z. Peak-peak width Hpp of the signals decreases with falling temperature until minimum value and rises sharply with further decreasing temperature, which is approximated by Hpp = C0 +C1/T + BT. The Hpp behavior at high temperature and at low temperature can be analyzed by Korringa mechanism and slowing down of Fe3+ spin fluctuation, respectively. From the analysis of coefficient B's of Korringa terms, C0 and g-shift, it is revealed that the magnetic interaction of Fe3+ with hole carriers and Ce2+ spins depends strongly on hole density. 相似文献
3.
The paper contains a review of some results concerning probability theory on MV algebras (laws of large numbers, central
limit theorem, martingale convergence theorem). Also some algebraic and methodical aspects are discussed. 相似文献
4.
Junya Kojima Masanori Ono Naoaki Kuji Hirotaka Nishi 《International journal of molecular sciences》2022,23(14)
In humans, the placenta provides the only fetomaternal connection and is essential for establishing a pregnancy as well as fetal well-being. Additionally, it allows maternal physiological adaptation and embryonic immunological acceptance, support, and nutrition. The placenta is derived from extra-embryonic tissues that develop rapidly and dynamically in the first weeks of pregnancy. It is primarily composed of trophoblasts that differentiate into villi, stromal cells, macrophages, and fetal endothelial cells (FEC). Placental differentiation may be closely related to perinatal diseases, including fetal growth retardation (FGR) and hypertensive disorders of pregnancy (HDP), and miscarriage. There are limited findings regarding human chorionic villous differentiation and placental development because conducting in vivo studies is extremely difficult. Placental tissue varies widely among species. Thus, experimental animal findings are difficult to apply to humans. Early villous differentiation is difficult to study due to the small tissue size; however, a detailed analysis can potentially elucidate perinatal disease causes or help develop novel therapies. Artificial induction of early villous differentiation using human embryonic stem (ES) cells/induced pluripotent stem (iPS) cells was attempted, producing normally differentiated villi that can be used for interventional/invasive research. Here, we summarized and correlated early villous differentiation findings and discussed clinical diseases. 相似文献
5.
Kan‐Hua Lee Kenji Araki Li Wang Nobuaki Kojima Yoshio Ohshita Masafumi Yamaguchi 《Progress in Photovoltaics: Research and Applications》2016,24(10):1310-1318
The paper presents a quantitative approach to the investigation and comparison of the material qualities of III–V on silicon (III–V/Si) solar cells by using external radiative efficiencies. We use this analysis to predict the limiting efficiencies and evaluate the criteria of material quality in order to achieve high‐efficiency III–V/Si solar cells. This result yields several implications for the design of high‐efficiency III–V/Si solar cells. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
6.
Kojima T. Miyajima M. Akaboshi F. Yogo T. Ishimoto S. Okuda A. 《Semiconductor Manufacturing, IEEE Transactions on》2000,13(3):293-299
We have developed a chemical mechanical polishing (CMP) process monitor which uses polishing vibration. The monitor enables us to accurately detect the polishing end point in copper (Cu) polishing even when the process conditions such as initial film thickness, slurry flow and polishing rate are changed and when polishing multilayer film. Furthermore, the monitor is not only applicable to Cu polishing but also to planarizing polishing of an inter-level dielectric layer. The monitor can be also used to control the processes and the equipment because of its capability to detect abnormalities in the polishing conditions 相似文献
7.
Shin D.S. Wang J. Bosch F. Kiely P.A. Chand N. Fischer M. Kojima K. Kasper B.L. Peral E.M. Ransijn H. 《Electronics letters》2002,38(16):864-865
A 1.3 μm uncooled transmitter with wide-open eye diagrams at laser temperatures of 20, 50, and 85°C is presented. Using this transmitter, it is demonstrated that 10 Gbit/s transmission is possible over a 50 km nonzero dispersion-shifted Lucent TrueWave-RS fibre. This result is compared with transmission over a 55 km standard singlemode fibre 相似文献
8.
Takeshi Yanagisawa Takeshi Kojima Tadamasa Koyanagi Kiyoshi Takahisa Kuniomi Nakamura 《Microelectronics Reliability》2002,42(2):219-223
Changes in the characteristics of CuInGaSe2 solar cells in response to light irradiation were investigated. Then these changes, which suggest long-term degradation, were clarified using the measurement technique by feeble light. The thin-film cell of this type is considered to be “ever stable”. A stable result over the short term was also obtained in the light accelerated test of 2-SUN performed in this experiment. On the other hand, it was found that the characteristics measured with feeble light show a remarkable change over time. As a result of measuring at 0.065–105 mW/cm2 light intensity, the change rate of cell output power was so intense the measurement light was weak. This finding reflects the increase in an internal defect and suggests a possibility that light irradiation exerts the influence on long-term cell performance. Moreover, by measuring with feeble light, we found that the changed output recovers by reverse voltage application. The phenomenon of recovery up on comparatively low reverse voltage can be considered as an application for maintaining stability. 相似文献
9.
This paper proposes a hybrid decoupled power flow method for balanced power distribution systems with distributed generation sources.The method formulates the power flow equations in active power and reactive power decoupled form with polar coordinates.Second-order terms are included in the active power mismatch iteration,and constant Jacobian and Hessian matrices are used.A hybrid direct and indirect solution technique is used to achieve efficiency and robustness of the algorithm.Active power correction is solved by means of a sparse lower triangular and upper triangular(LU) decomposition algorithm with partial pivoting,and the reactive power correction is solved by means of restarted generalized minimal residual algorithm with an incomplete LU pre-conditioner.Typical distribution generation models and distribution load models are included.The impact of zero-impedance branches is explicitly modeled through reconfiguring of the adjacent branches with impedances.Numerical examples on a sample distribution system with widespread photovoltaic installations are given to demonstrate the effectiveness of the proposed method. 相似文献
10.
Masami Kojima Yukihisa Suzuki Kensuke Sasaki Masao Taki Kanako Wake Soichi Watanabe Maya Mizuno Takafumi Tasaki Hiroshi Sasaki 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(9):912-925
The objective of this study was to develop a model of ocular damage induced by 40, 75, and 95 GHz continuous millimeter waves (MMW), thereby allowing assessment of the clinical course of ocular damage resulting from exposure to thermal damage-inducing MMW. This study also examined the dependence of ocular damage on incident power density. Pigmented rabbit eyes were exposed to 40, 75, and 95 GHz MMW from a spot-focus-type lens antenna. Slight ocular damage was observed 10 min after MMW exposure, including reduced cornea thickness and reduced transparency. Diffuse fluorescein staining around the pupillary area indicated corneal epithelial injury. Slit-lamp examination 1 day after MMW exposure revealed a round area of opacity, accompanied by fluorescence staining, in the central pupillary zone. Corneal edema, indicative of corneal stromal damage, peaked 1 day after MMW exposure, with thickness gradually subsiding to normal. Three days after exposure, ocular conditions had almost normalized, though corneal thickness was slightly greater than that before exposure. The 50% probability of ocular damage (DD50) was in the order 40?>?95?≈?75 GHz at the same incident power densities. 相似文献