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21.
Kinoshita Kengo; Sadanami Keishi; Kidera Akinori; Go Nobuhiro 《Protein engineering, design & selection : PEDS》1999,12(1):11-14
In order to search for a common structural motif in the phosphate-bindingsites of proteinmononucleotide complexes, we investigatedthe structural variety of phosphate-binding schemes by an all-against-allcomparison of 491 binding sites found in the Protein Data Bank.We found four frequently occurring structural motifs composedof protein atoms interacting with phosphate groups, each ofwhich appears in different protein superfamilies with differentfolds. The most frequently occurring motif, which we call thestructural P-loop, is shared by 13 superfamilies and is characterizedby a four-residue fragment, GXXX, interacting with a phosphategroup through the backbone atoms. Various sequence motifs, includingWalker's A motif or the P-loop, turn out to be a structuralP-loop found in a few specific superfamilies. The other threemotifs are found in pairs of superfamilies: protein kinase andglutathione synthetase ATPase domain like, actin-like ATPasedomain and nucleotidyltransferase, and FMN-linked oxidoreductaseand PRTase. 相似文献
22.
Keiichirou Yonezawa Alexander Hinderhofer Takuya Hosokai Kengo Kato Rintaro Makino Frank Schreiber Nobuo Ueno Satoshi Kera 《Advanced Materials Interfaces》2014,1(5)
The dependence of the energy level alignment (ELA) on structural defects at an organic/organic heterojunction (OOH) of perfluoropentacene (PFP)‐on‐diindenoperylene (DIP) was investigated using X‐ray scattering and ultraviolet photoelectron spectroscopy. The density of structural defects near the interface between the PFP and DIP layers was varied by changing the growth temperature of the DIP film. A direct relationship was found between the defect density and the ELA at the OOH; the ELA together with the change in the electrostatic potential (quasi‐interface dipole layer) at the OOH varies systematically with the defect density near the interface. This indicates that a key factor affecting the ELA is the electrostatic potential change across the OOH interface, which is produced by electron transfer from DIP occupied gap states to PFP unoccupied gap states. These gap states originate from the defects and are effectively controlled by adjusting the growth conditions of the organic films. As a result, the ELA at OOH interfaces can be controlled by the density of structural defect, which is important for organic devices employing OOHs, such as organic photovoltaic cells. 相似文献
23.
Kengo Yoshida Renald BrennerBrigitte Bacroix Salima Bouvier 《Materials Science and Engineering: A》2011,528(3):1037-1046
Work-hardening behavior of single-phase steel and dual-phase steel which is made of hard martensite surrounded by soft ferrite is analyzed by using an elastoplastic crystal plasticity model in conjunction with the incremental self-consistent model. Two-stage loading paths consisting of uniaxial tension, unloading and subsequent uniaxial tension/compression for various directions are applied. Bauschinger effect and transitional re-yielding behavior, which depends on the direction of the second loading path, are predicted and analyzed with respect to the distribution of the residual resolved shear stresses within the material. These features, which are caused by the inhomogeneity of the residual stress field, are especially pronounced in the case of the dual-phase steel because of the strong mechanical contrast between ferrite and martensite phases. 相似文献
24.
25.
Artemisia princeps is commonly used as a food ingredient and in traditional Asian medicine. In this study, we examined the effects of long-term administration of an ethanol extract of A. princeps (APE) on body weight, white adipose tissue, blood glucose, insulin, plasma and hepatic lipids, and adipocytokines in C57BL/6 mice fed a high-fat diet. Daily feeding of a 1% APE diet for 14 weeks normalized elevated body weight, white adipose tissue, and plasma glucose and insulin levels, and delayed impaired glucose tolerance in mice a fed high-fat diet. These events were not observed in mice fed a control diet containing 1% APE. Liver triglyceride and cholesterol levels were similar in mice fed a 1% APE-diet and those fed a control diet. In the high-fat diet groups, APE inhibited hepatic fatty acid synthase (FAS) and suppressed the elevation of plasma leptin, but had no effect on adiponectin levels. These findings suggest that the regulation of leptin secretion by APE may inhibit FAS activity with subsequent suppression of triglyceride accumulation in the liver and adipose tissues. Inhibition of lipid accumulation can, in turn, lead to improvements in impaired glucose tolerance. 相似文献
26.
Kengo Hashimoto 《Annals of Nuclear Energy》1993,20(12):789-797
An eigenvalue problem governing BWR core nuclear thermal-hydraulic modes which result in out-of-phase power oscillations is formulated. This formulation is based on the linearization approximation to nonlinear feedback terms and the very simple models for neutronics and thermal-hydraulics. The eigenvalue problem in 5 × 5 matrix formulation can be easily solved without using a computer. A series of the calculations are carried out, at a high-power and low-core-flow condition, to investigate the dependence of the eigenvalues and eigenfunctions on the void reactivity coefficient and the subcriticality of spatial neutronic modes, where the latter parameter is identical to the eigenvalue separation of the higher-harmonic neutronic mode. These results show that the threshold value of the void coefficient for initiating the unstable out-of-phase oscillation strongly depends on the subcriticality. The oscillation mode becomes more unstable with an increase in the absolute value of the negative void coefficient, whereas the mode becomes more stable, almost linearly, with increasing subcriticality. The resonant frequency of the oscillation and the phase shifts between the nuclear thermal-hydraulic variables are consistent with previous measured or calculated values. 相似文献
27.
Behaviormetrika - Experiments were carried out on the pitch of two groups of computer-generated complex tones. The sequence of the ten complex tones in group A are perceived as an endless scale... 相似文献
28.
The effects of niobium addition on a completely austenitic stainless steel matrix consisting of Fe-15%Cr-15%Ni, with about 0, 0.5, 1 and 2% niobium, were studied by determination of stacking fault energies by means of X-ray diffraction analysis. A strong influence of niobium on stacking-fault energies was found, whose behaviour can be explained as being due to decrease in the electron/atom ratio and increase in the L. Pauling electron vacancy number of austenitic Fe-Cr-Ni matrix brought on by niobium. 相似文献
29.
The corrosion behaviour of SS 41 steel in formic acid and acetic acid was investigated by measuring the corrosion weight loss, the polarization curve and the impedance at the steel-solution interface. It was found that the corrosion rates of the steel in formic acid and acetic acid are markedly dependent on acid concentration and temperature. The corrosion rates in acetic acid are smaller than those in formic acid. The corrosion potential Ecorr against pH of formic acid and acetic acid solutions shows a linear relationship. 相似文献
30.
Ethanol and lactic acid production using sap squeezed from old oil palm trunks felled for replanting
Akihiko Kosugi Ryohei Tanaka Kengo Magara Yoshinori Murata Takamitsu Arai Othman Sulaiman Rokiah Hashim Zubaidah Aimi Abdul Hamid Mohd Khairul Azri Yahya Mohd Nor Mohd Yusof Wan Asma Ibrahim Yutaka Mori 《Journal of Bioscience and Bioengineering》2010,110(3):322-325
Old oil palm trunks that had been felled for replanting were found to contain large quantities of high glucose content sap. Notably, the sap in the inner part of the trunk accounted for more than 80% of the whole trunk weight. The glucose concentration of the sap from the inner part was 85.2 g/L and decreased towards the outer part. Other sugars found in relatively low concentrations were sucrose, fructose, galactose, xylose, and rhamnose. In addition, oil palm sap was found to be rich in various kinds of amino acids, organic acids, minerals and vitamins. Based on these findings, we fermented the sap to produce ethanol using the sake brewing yeast strain, Saccharomyces cerevisiae Kyokai no.7. Ethanol was produced from the sap without the addition of nutrients, at a comparable rate and yield to the reference fermentation on YPD medium with glucose as a carbon source. Likewise, we produced lactic acid, a promising material for bio-plastics, poly-lactate, from the sap using the homolactic acid bacterium Lactobacillus lactis ATCC19435. We confirmed that sugars contained in the sap were readily converted to lactic acid with almost the same efficiency as the reference fermentation on MSR medium with glucose as a substrate. These results indicate that oil palm trunks felled for replanting are a significant resource for the production of fuel ethanol and lactic acid in palm oil-producing countries such as Malaysia and Indonesia. 相似文献