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991.
Shinya Otsuka Yoshikazu Kurose Zensaku Kozuka 《Metallurgical and Materials Transactions B》1984,15(1):141-147
The activity coefficient of oxygen, γo, in liquid Bi-Pb and Bi-Sb alloys at 1073 K has been measured over the entire composition range utilizing a modified coulometric
titration method with the electrochemical cell: O in liquid Bi-Pb or Bi-Sb alloys/ZrO2(+CaO)/Air, Pt. The measured In y0 values for both systems, plotted in terms of alloy composition, lie on upwardly concave
curves. This behavior is significantly different from what is predicted by the quasi-chemical equations. The models of Wagner
and of Blanderet al., which involve one adjustable parameter,h, give a satisfactory representation of the data.
YOSHIKAZU KUROSE, formerly a Graduate Student, Osaka University, Osaka, 565, Japan 相似文献
992.
993.
Shinya Otsuka Masami Matsuyama Zensaku Kozuka 《Metallurgical and Materials Transactions B》1978,9(2):21-24
The oxygen diffusivity in liquid copper-lead alloys at 1403 K (1130‡C) was measured us-ing the electrochemical cell: Ni-NiOJZrO2(+CaO)/O in liquid Cu-Pb alloy(I)/ZrO2(+CaO)/O in liquid Cu-Pb alloy(II). Oxygen in liquid Cu-Pb alloy(I) was transferred to the right by applying a preselected
voltage between the two liquid Cu-Pb alloys. The oxygen diffusivity in liquid Cu-Pb alloy(I) was calculated from the emf change
with time between the Ni-NiO and liquid Cu-Pb alloy (I) electrodes. The results were: Do (in pure Cu) = 8.14 (+0.70
-0.43) × 105 cm2/s, Do (in Cu-25 at. pct Pb) = 11.4(+0.4
-0.6) × 10-5 cm2/s, Do (in Cu-50 at. pct Pb) = 12.9(+1.9
-1.5) × 10-5 cm2/s, Do (in Cu-75 at. pct Pb) = 11.0(+2.4
-1.2) x 10-5 cm2/s, Do (in pure Pb) = 26.3(+4.8
-3.7) × 10-5 cm2/s. It was found that the oxygen diffusivity in liquid copper-lead alloys did not change dras-tically over the entire composition
range, in contrast with that reported by other investi-gators for liquid copper-nickel alloys. The oxygen diffusivity in pure
liquid lead agreed with the results of our previous work using an FeO-Fe3O4 mixture as a sink for oxygen. 相似文献
994.
995.
Wacker type and π-allyl type oxidations of propylene controlled by fuel cell system in the gas phase
Kiyoshi Otsuka Yasuo Shimizu Ichiro Yamanaka Takayuki Komatsu 《Catalysis Letters》1989,3(5-6):365-369
Oxidation of propylene applying the (C3H6, Pd/H3PO4/Pt, O2) fuel cell system in the gas phase produced acrolein and acrylic acid, the -allyl type oxidation products. However, addition of H2PdCl4 or HCl to the electrolyte reduced the -allyl oxidation, but enhanced Wacker type oxidation producing acetone. Direction to either Wacker type or -allyl type oxidation can easily be controlled electrochemically by applying the fuel cell system in the gas phase. 相似文献
996.
The polarisation-dependent gain spectra were measured for multi-quantum-well laser diodes. Differences in the gain-current relationship and in the peak gain wavelength between TE and TM polarisations are explained by a newly developed model. 相似文献
997.
998.
Interferons (IFNs) have been reported to have pleiotrophic effects including the ability to induce the production of other cytokines in several cell types. Tumour necrosis factor alpha (TNF-alpha) is pro-inflammatory cytokine a known to be produced by a variety of cells including human keratinocytes. In the present study, we sought to determine the effects of IFNs on TNF-alpha production from human keratinocytes. IFN-gamma (50-100 ng/ml) induced TNF-alpha production dose dependently, but no induction of TNF-alpha was observed with IFN-alpha or IFN-beta. Since in the epidermis cytokines often work with in a cascade fashion and keratinocytes are a source of primary cytokine, IL-1 alpha, whether combined treatment with IFN-gamma and IL-1 alpha had a synergistic effect on TNF-alpha production was examined. Combined treatment with IFN-gamma (100 ng/ml) and IL-1 alpha (10 ng/ml) induced 2-3-fold higher level of TNF-alpha than IL-1 alpha alone. These results suggest that IFN-gamma is a positive regulator for the production of TNF-alpha from human keratinocytes and likely to increase skin inflammation. 相似文献
999.
Tape-wound toroidal cores are used widely as magnetic devices of electronic equipment and instruments. In the design of equipment employing magnetic cores, it is necessary to know the relation between the magnetic properties of the core and the magnetic properties of the material. This paper describes the effect of the dimension ratio of the core on the magnetic properties for the sinusoidal flux waveform drive condition. In carrying out the analysis, a mode analysis in which the magnetization characteristics are approximated by a piecewise-linear curve is adopted. From the results obtained by the numerical analysis, local flux waveforms and exciting current waveforms of the core are shown. As a result, the relation between iron loss and magnetizing apparent power of the core and the dimension ratio is derived. These results were confirmed by experiments. 相似文献
1000.
H Otsuka T Kusumi S Kanai M Koyama Y Kuno R Takizawa 《Canadian Metallurgical Quarterly》1998,102(5):757-764
BACKGROUND: In allergic rhinitis, mast cells are increased in number in the epithelium of the nasal mucosa and play an important role in the immediate response. However, the mechanism of the accumulation is not known. OBJECTIVE: The purpose of this study was to determine whether the nasal epithelial cells produce stem cell factor (SCF), the mast cell growth and chemoattractant factor, and contribute mast cell hyperplasia in the epithelium of allergic rhinitis. METHODS: We have characterized the cellular localization of SCF using immunohistochemistry, reverse transcribed-PCR, and ELISA; compared SCF production of cultured epithelial cells between patients with allergic rhinitis and nonallergic subjects; and compared the SCF production with the number of mast cells and the histamine content in the nasal epithelial scrapings. RESULTS: Immunohistochemically, SCF was identified in the nasal epithelium of the biopsy specimens and in cultured nasal epithelial cells. SCF mRNA was expressed by cultured nasal epithelial cells not only in patients with allergy but also in subjects with no allergy. However, the SCF/beta-actin mRNA ratio and SCF production in day 7 cultured epithelial cells was significantly higher in allergic than in nonallergic subjects (P =. 0424, P =.0085, respectively). SCF production from nasal scrapings in culture was strongly correlated with the number of mast cells (r = 0.506, P =.0023) and the histamine content (r = 0.480, P =.0040). CONCLUSIONS: These findings demonstrate that nasal epithelial cells produce SCF and may be important in the attraction, proliferation, and activation of mast cells in allergic inflammation in the nose. 相似文献