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91.
Toshio Oishi Tetsuya Goto Yoshiro Kayahara Katsutoshi Ono Joichiro Moriyama 《Metallurgical and Materials Transactions B》1982,13(3):423-427
The thermodynamic properties of silica-saturated iron silicate slags have been studied from oxygen partial pressure measurements using a solid electrolyte galvanic cell. The oxygen activity in molten silver bath equilibrated with iron silicate slags was determined by the following cell type, Pt, Ni-NiO/O=/slag-Ag(O), LaCrO3, Pt at temperatures between 1473 and 1573 K for the slags ranging in compositions from iron saturation to magnetite saturation. The oxygen partial pressures obtained in this investigation were in good agreement with those given by the previous study using the CO-CO2 gas equilibrium method. The data showed that the Fe+++/Fe++ ratio is proportional toP o 2 ¼ 相似文献
92.
Tetsushi N. Deura Tomoya Matsunaga Ryosuke O. Suzuki Katsutoshi Ono Masahiro Wakino 《Metallurgical and Materials Transactions B》1998,29(6):1167-1174
A process to produce titanium powder continuously is proposed and its applicability is examined experimentally. The method
is based on the chemical reaction in the conventional Kroll reduction process; however, TiCl4 gas is injected into molten salt on which a molten magnesium layer is floated as the reductant. Bubbles of gaseous TiCl4 can be reacted at the lower surface of the liquid Mg layer, while TiCl4 gas reacts on the upper surface in the Kroll process. The fine Ti particles produced in this study were well separated from
magnesium and could be recovered from the bottom of the molten salts. The particles were small and fine enough for use in
powder metallurgy, while congregated lumps of about 20 μm in size are obtained by the Kroll process. The composition of molten
salts and an operation temperature above 1073 K did not affect the morphology of the Ti particles, if suitable material for
the reaction vessel was chosen. 相似文献
93.
Katsutoshi Ueno Kinya Miura Osamu Kusakabe Migitoshi Nishimura 《Canadian Metallurgical Quarterly》2001,127(3):275-281
A simplified method for estimating the ultimate bearing capacity of surface footings on sand is described with special attention to the dependency of the angle of internal friction of sand on confining stress. An extended slip line method is developed, in which the dependency of the angle of internal friction on the confining stress is formulated from results of conventional triaxial compression tests for various sands. Based on results from a comprehensive series of calculations employing the extended slip line method, the writers reappraise size effects on bearing capacity and investigate the relationship between strength parameters of sand and size effects on bearing capacity. A modified formula and several diagrams that provide a simple estimation method are proposed to consider size effects on bearing capacity. A comparison between estimations using the formula and ultimate bearing capacities measured from several series of centrifuge tests demonstrates the practicability of the proposed method for both strip and circular footings. 相似文献
94.
Shoji Yozo Hida Takahiro Tsukamoto Katsutoshi Komaki Shozo 《Wireless Personal Communications》2000,14(2):183-197
Asynchronous TDMA bus-link systems using chirp multiplexing transform(CMT) are proposed for radio highway networks to provide the flexibleconstruction of fiber-optic radio access networks and thepossibility of the universal use of these networks among future diverseradio services. The CMT equipped at the radio base station performs twofunctions. One is the conversion of FDM multiple radio services intosignals with a TDMA format and the other is the time compression ofthe generated signal in order to allow asynchronous access. As aresult, the proposed systems can realize the unified transmission ofmultiple radio services and the switching of them in the optical stage(photonic routing) in the networks according to the type of radioservice. The realization of such photonic routing of the radio servicewould greatly benefit the goal of a seamless and universalnetwork available to different types of radio service. Therelationship between the pulse-loss probability performance and thecall-blocking probability performance is theoretically analyzed. Theeffect on the performance of traffic partiality in the coveredarea and the way the performance can be improved are theoreticallyinvestigated. Finally, one of the ways to determine the network sizecovered by a bus link and the number of connected radio base stationsis introduced. 相似文献
95.
96.
Katsutoshi Hori Masahito Ishikawa Mariko Yamada Aisuke Higuchi Yu Ishikawa Hironori Ebi 《Journal of Bioscience and Bioengineering》2011,111(1):31-36
The toluene-degrading bacterium Acinetobacter sp. Tol 5 is highly adhesive through cell-surface nanofibers. Previously, we identified two morphologically distinct nanofibers on Tol 5 cells, namely, nonperitrichate anchor-like and peritrichate pilus-like nanofibers. In the present study, the application of improved electron microscopy techniques enabled discrimination of three distinct types of peritrichate nanofibers on Tol 5 cells. Interestingly, production of these nanofibers was affected by the available growth substrate. Thick, long, straight nanofibers a, which were present on cells grown on toluene, lactate, and ethanol, were not observed on cells grown on triacylglycerol (TAG). In contrast, cells grown on TAG were covered with long, curved nanofibers c, which only existed sparsely on cells grown on toluene, lactate, and ethanol. Thin, short, straight nanofibers b were found densely covering the margin of cells grown on all four growth substrates. SDS-PAGE of Tol 5 cell-surface proteins detected a protein of 17.5 kDa that was expressed at a high level on ethanol, but was undetectable on TAG. Conversely, a 26 kDa protein was identified that was exclusively expressed on TAG, but was only faintly expressed by cells grown on the other substrates. Based on N-terminal amino acid sequences, the 17.5 and 26 kDa proteins were identified as the major subunits of type 1 and Fil pili, respectively, which are typical bacterionanofibers. From these results, we deduced that nanofibers a and c are type 1 and Fil pili, respectively. The adhesiveness of Tol 5 cells was low only when they were grown on TAG. 相似文献
97.
Paudyal H Pangeni B Inoue K Kawakita H Ohto K Harada H Alam S 《Journal of hazardous materials》2011,192(2):676-682
Adsorption gels for fluoride ion were prepared from orange waste by saponification followed by metal loading. The pectin compounds contained in orange waste creates ligand exchange sites once it is loaded with multi-valent metal ions such as Al3+, La3+, Ce3+, Ti4+, Sn4+, and V4+ to be used for fluoride removal from aqueous solution. The optimum pH for fluoride removal depends on the type of loaded metal ions. The isotherm experiments showed the Langmuir type monolayer adsorption. Among all kinds of metal loaded gels tested, Al loaded gel appeared to exhibit the most favorable adsorption behavior. The adsorption kinetics of fluoride on loaded gel demonstrated fast adsorption process. The presence of NO3−, Cl− and Na+ ions has negligible effect on fluoride removal whereas SO42− and HCO3− retarded the fluoride removal capacity in some extent. Fluoride removal at different adsorbent doses showed that fluoride concentration can be successfully lowered down to the acceptable level of environmental standard. The fluoride adsorption mechanism was interpreted in terms of ligand exchange mechanism. The complete elution of adsorbed fluoride from the gel was successfully achieved using NaOH solution. 相似文献
98.
Uneven shrinkage behavior between cement paste and rock aggregate takes place when concrete is subjected to drying. Possible consequences including internal damage and strain distribution need to be researched to understand the changes in concrete properties over time. In this study, strain distributions over the cross section of sliced concrete specimens with age were determined using a digital image correlation method (DICM). After shrinkage had developed, crack distributions were visually observed using a fluorescent epoxy impregnation method (FEIM). High correlation was found between expansive strain at the maximum principal strain distribution obtained with DICM and positions of cracks obtained with FEIM, suggesting that DICM can be applied to the damage evaluation of a concrete cross section over time. Even the present DICM and FEIM studies are results of surface cracking of specimens, which is strongly affected by the water transfer process and resultant three dimensional stress distribution, the following findings were obtained: the area of internal fine cracks increased with increase in aggregate size, correlation was confirmed between the area of fine cracks and macroscopic strain of concrete, and two types of fine cracks were confirmed—cracks restrained by aggregate and interfacial cracks between aggregate and mortar as a result of stress arch formation. 相似文献
99.
Dilruba Sharmin Yu Sasano Minetaka Sugiyama Satoshi Harashima 《Yeast (Chichester, England)》2014,31(10):393-409
A key mechanism of signal transduction in eukaryotes is reversible protein phosphorylation, mediated through protein kinases and protein phosphatases (PPases). Modulation of signal transduction by this means regulates many biological processes. Saccharomyces cerevisiae has 40 PPases, including seven protein phosphatase 2C (PP2C PPase) genes (PTC1–PTC7). However, their precise functions remain poorly understood. To elucidate their cellular functions and to identify those that are redundant, we constructed 127 strains with deletions of all possible combinations of the seven PP2C PPase genes. All 127 disruptants were viable under nutrient‐rich conditions, demonstrating that none of the combinations induced synthetic lethality under these conditions. However, several combinations exhibited novel phenotypes, e.g. the Δptc5Δptc7 double disruptant and the Δptc2Δptc3Δptc5Δptc7 quadruple disruptant exhibited low (13°C) and high (37°C) temperature‐sensitive growth, respectively. Interestingly, the septuple disruptant Δptc1Δptc2Δptc3Δptc4Δptc5Δptc6Δptc7 showed an essentially normal growth phenotype at 37°C. The Δptc2Δptc3Δptc5Δptc7 quadruple disruptant was sensitive to LiCl (0.4 m ). Two double disruptants, Δptc1Δptc2 and Δptc1Δptc4, displayed slow growth and Δptc1Δptc2Δptc4 could not grow on medium containing 1.5 m NaCl. The Δptc1Δptc6 double disruptant showed increased sensitivity to caffeine, congo red and calcofluor white compared to each single deletion. Our observations indicate that S. cerevisiae PP2C PPases have a shared and important role in responses to environmental stresses. These disruptants also provide a means for exploring the molecular mechanisms of redundant PTC gene functions under defined conditions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
100.
Hiroki Shimada Shuko Hata Yuto Yamazaki Yuri Otsubo Ikuko Sato Kazue Ise Atsushi Yokoyama Takashi Suzuki Hironobu Sasano Akira Sugawara Yasuhiro Nakamura 《International journal of molecular sciences》2022,23(21)
Primary aldosteronism (PA) is considered the most common form of secondary hypertension, which is associated with excessive aldosterone secretion in the adrenal cortex. The cause of excessive aldosterone secretion is the induction of aldosterone synthase gene (CYP11B2) expression by depolarization of adrenocortical cells. In this study, we found that YM750, an Acyl-coenzyme A: cholesterol acyltransferase (ACAT) inhibitor, acts on adrenocortical cells to suppress CYP11B2 gene expression and aldosterone secretion. YM750 inhibited the induction of CYP11B2 gene expression by KCl stimulation, but not by angiotensin II and forskolin stimulation. Interestingly, YM750 did not inhibit KCl-stimulated depolarization via an increase in intracellular calcium ion concentration. Moreover, ACAT1 expression was relatively abundant in the zona glomerulosa (ZG) including these CYP11B2-positive cells. Thus, YM750 suppresses CYP11B2 gene expression by suppressing intracellular signaling activated by depolarization. In addition, ACAT1 was suggested to play an important role in steroidogenesis in the ZG. YM750 suppresses CYP11B2 gene expression and aldosterone secretion in the adrenal cortex, suggesting that it may be a potential therapeutic agent for PA. 相似文献