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排序方式: 共有948条查询结果,搜索用时 15 毫秒
81.
Yoshifumi Nagano Akihiro Orita Junzo Otera 《Advanced Synthesis \u0026amp; Catalysis》2003,345(5):643-646
The high atom efficiency was achieved through addition of Ac2O in the Sc(OTf)3‐catalyzed allylation of aldehyde with tetraallytin in a 4 : 1 molar ratio. 相似文献
82.
Inside Cover: Biosynthetic Gene Cluster for Surugamide A Encompasses an Unrelated Decapeptide,Surugamide F (ChemBioChem 18/2016) 下载免费PDF全文
83.
Keiichi Matsubara Takashi Higaki Yuko Matsubara Akihiro Nawa 《International journal of molecular sciences》2015,16(3):4600-4614
Preeclampsia (PE) is characterized by disturbed extravillous trophoblast migration toward uterine spiral arteries leading to increased uteroplacental vascular resistance and by vascular dysfunction resulting in reduced systemic vasodilatory properties. Its pathogenesis is mediated by an altered bioavailability of nitric oxide (NO) and tissue damage caused by increased levels of reactive oxygen species (ROS). Furthermore, superoxide (O2−) rapidly inactivates NO and forms peroxynitrite (ONOO−). It is known that ONOO− accumulates in the placental tissues and injures the placental function in PE. In addition, ROS could stimulate platelet adhesion and aggregation leading to intravascular coagulopathy. ROS-induced coagulopathy causes placental infarction and impairs the uteroplacental blood flow in PE. The disorders could lead to the reduction of oxygen and nutrients required for normal fetal development resulting in fetal growth restriction. On the other hand, several antioxidants scavenge ROS and protect tissues against oxidative damage. Placental antioxidants including catalase, superoxide dismutase (SOD), and glutathione peroxidase (GPx) protect the vasculature from ROS and maintain the vascular function. However, placental ischemia in PE decreases the antioxidant activity resulting in further elevated oxidative stress, which leads to the appearance of the pathological conditions of PE including hypertension and proteinuria. Oxidative stress is defined as an imbalance between ROS and antioxidant activity. This review provides new insights about roles of oxidative stress in the pathophysiology of PE. 相似文献
84.
Keiko Ohtsuka Hajime Kimura Toshiyuki Iwai Akihiro Matsumoto 《Polymer International》2014,63(4):752-759
Sulfur‐containing allyl ester, which reacts with diallyl phthalate (DAP) resin to have allyl groups, was synthesized by the reaction of allyl phthalic acid with bisphenol having sulfur atoms. The sulfur‐containing allyl ester compound was blended with DAP resin to improve the adhesive properties to copper. By modification with sulfur‐containing allyl ester compound, the T‐peel adhesive strength and the lap shear adhesive strength to copper was improved. In particular, the adhesive strength was greatly improved when the resin was modified with the allyl ester compound having a disulfide bond (?S?S?) (DADS). It is concluded that this result is due to the improvement of the interfacial adhesive strength because the sulfur atom was found to be located in the surface of the copper by Fourier transform infrared (FTIR) analysis. The glass transition temperature (Tg) and the thermal decomposition temperature (Td) of the cured DAP resin modified with DADS slightly decreased with increasing concentration of DADS. The lowering of Tg is because the crosslinking density of the DAP resin modified with DADS is smaller than that of DAP resin. Moreover, from thermogravimetric analysis, the lowering of Td of the DAP resin modified with DADS is because DADS is likely to pyrolyze. © 2013 Society of Chemical Industry 相似文献
85.
Peerawut Yutthagowith Akihiro Ametani Naoto Nagaoka Yoshihiro Baba 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(4):324-330
This article presents calculations of tower surge responses and insulator voltages of an actual transmission tower including ground wires and phase wires. The partial element equivalent circuit (PEEC) method is applied as a simulation tool. Surge responses of the tower and insulator voltages calculated by the PEEC method are compared with electro magnetic transients program (EMTP) simulated results and experimental results collected from the literatures. The results calculated by the PEEC method agree well with the experimetal results, not only amplitudes but also waveshapes. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
86.
There are many multi‐input multi‐output (MIMO) systems in chemical plants, and they have multiple time delays of different length in each input and output pair. This paper explains a two‐degree‐of‐freedom (2DOF) control system based on generalized minimum variance control (GMVC) for MIMO systems. It can improve the tracking performance with respect to the reference signals and the response properties for the disturbance. The states between the sampling period can be expressed by using the modified z transform to take account of multiple time delays. Additionally, a tracking controller is designed to decouple the plant. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(1): 28–36, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21046 相似文献
87.
Hiroki Nagasawa Akihiro Yamasaki Atsushi Iizuka Kazukiyo Kumagai Yukio Yanagisawa 《American Institute of Chemical Engineers》2009,55(12):3286-3293
Bipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
88.
Akihiro Yamamoto 《New Generation Computing》1999,17(1):99-117
We propose in this paper an inference method called Bottom Generalization for Inductive Logic Programming (ILP, for short).
We give an inference procedure based on it, and prove that a hypothesis clauseH is derived by the procedure from an exampleE under a background theoryB iffH subsumesE relative toB in Plotkin’s sense. The theoryB can be any clausal theory, and the exampleE can be any clause which is not implied byB. The derived hypothesisH is a clause, but is not always definite. The result is proved by defining a declarative semantics for arbitrary consistent
clausal theories, and showing that SB-resolution, which was originally introduced by Plotkin, gives their complete procedural
semantics. We also show that Bottom Generalization is more powerful than both Jung’s method based on theV-operator and Saturant Generalization by Rouveirol, but not than Inverse Entailment by Muggleton. At the ILP ’97 workshop
we called our inference method “Inverse Entailment,” but we have renamed it “Bottom Generalization” because we found that
it differs from the original definition of Inverse Entailment.
The main part of this work was accomplished while the author was visiting the Artificial Intelligence Group, Department of
Computer Science, Technical University Darmstadt, Germany.
Akihiro Yamamoto, Dr.: He is an Associate Professor of the Division of Electronics and Information Engineering at Hokkaido University. He received
the B.S. degree from Kyoto University in 1985, and the M.S. and Dr.Sci. degrees from Kyushu University in 1987 and 1990 respectively.
He was a guest researcher of Oxford University Computing Laboratory, the United Kingdom, from January 1996 to March 1996,
and of Department of Computer Science at Technical University Darmstadt, Germany, from June 1996 to May 1997. His present
interests include the application of Logic Programming and Theorem Proving to Machine Learning. 相似文献
89.
90.
Kazuya Sasaki Takayuki Terai Akihiro Suzuki 《International Journal of Applied Ceramic Technology》2009,6(3):362-372
The microstructure of a thermal shielding material affects its thermal conductivity and mechanical property. In this study, the effects of the sintering temperature and the polymethyl methacrylate powder as a pore-former on the microstructure of a sintered porous yttria-stabilized zirconia (YSZ), which is used as a durable thermal shielding material, were investigated. It became clear that the microstructure of the sintered YSZ could be controlled by the particle size and the amount of the pore-former and the sintering temperature. The effect of the yttria amount in the YSZ on the microstructure was also clarified. 相似文献