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61.
Usp9x, an X-linked deubiquitylating enzyme, is stage dependently expressed in the supporting cells (i.e. Sertoli cells and granulosa cells) and germ cells during mouse gametogenesis. Af-6, a cell junction protein, has been identified as a substrate of Usp9x, suggesting a possible association between Usp9x and Af-6 in spermatogenesis and oogenesis. In this study, we examined the expression pattern of Af-6 and Usp9x and their intracellular localization in testes and ovaries of mice treated with or without pregnant mare serum gonadotropin (PMSG), an FSH-like hormone. In both testes and ovaries, Af-6 expression was predominantly observed in supporting cells, as well as in steroidogenic cells, but not in any germ cells. In Sertoli cells, Af-6 was continuously expressed throughout postnatal and adult stages, where both Af-6 and Usp9x were enriched at the sites of Sertoli-Sertoli and Sertoli-spermatid junctions especially at stages XI-VI. In the granulosa cells, Af-6, as well as Usp9x, was highly expressed in primordial and primary follicles, but its expression rapidly decreased after the late-secondary follicle stage. Interestingly, in PMSG-treated mice, the expression levels of Af-6 and Usp9x were synchronously enhanced, slightly in Sertoli cells and strongly in granulosa cells of the late-secondary and Graafian follicles. Such closely correlated expression patterns between Af-6 and Usp9x clearly suggest that Af-6 may be deubiquitylated by Usp9x in both Sertoli and granulosa cells. It further suggests that the post-translational regulation of Af-6 by Usp9x may be one potential pathway to control the cell adhesion dynamics in mammalian gametogenesis.  相似文献   
62.
Platinum thin films grown by chemical vapor deposition (CVD) using a liquid precursor of (methylcyclopentadienyl)trimethylplatinum were characterized in terms of crystallographic nature, morphology, contaminants, and their influence on electrical properties. The lattice constant of these CVD films (3.91–3.92 Å) is smaller than that of bulk platinum. A high oxygen contaminant is observed, irrespective of the oxygen ratio during growth. A film grown at low oxygen content consists of randomly oriented micro-grains and contains a large amount of carbon contaminants. When the film is grown under oxidative conditions, it shows a 111-textured cylindrical morphology with increasing thickness. The electric resistivity is higher than the bulk standard, and it increases with decreasing oxygen ratio during the film growth. These results indicate that the carbon contaminant causes the randomly oriented micro-grains and contributes to the high residual resistivity.  相似文献   
63.
The superconducting field winding of the 70-MW classhigh-response excitation superconducting generator requires a maximum operation current of 4.5 kA at the field of 6 T and needs to allow the field change of 10 T/s. In addition, superconductors have to meet the requirements of saddle-shape winding in the rotor slot and require the mechanical strength withstanding the centrifugal force as well as electromagnetic force. The developed conductor has the configuration of double stranded cable, consisting of NbTi, Cu and CuNi. An optimization was made, taking into account the requirement of low ac loss and high current density. The critical current of 13.6 kA was achieved at the field of 6 T and the ac loss was 6.9 kW/m3. The developed low-loss high-current density superconductor will be able to be applied to the field winding of the 70-MW class high-response excitation superconducting generator.  相似文献   
64.
A novel fitting procedure is proposed for a better determination of H2 rovibrational distribution from the Fulcher-a band spectroscopy. We have recalculated the transition probabilities and the results show that they deviate from Franck-Condon approximation especially for the non-diagonal transitions. We also calculated the complete sets of vibrationally resolved crosssections for electron impact d3∏u- X3∑g transition based on the semi-classical Gryzinski theory.An example of experimental study confirms that current approach provides a tool for a better diagnostics of H2 rovibrational distribution in electronic ground state.  相似文献   
65.
Fabrication of wurtzite-type gallium nitride (GaN) thick films on HPVE-grown {0001} GaN substrates under moderate ammonothermal conditions is reported. Supercritical ammonia (NH3) as solvent and the mineralizer ammonium chloride (NH4Cl) is employed for temperature and pressure conditions of 400–550 °C and ≤135 MPa, respectively. Growth rates of 30 μm per day over long-term growth runs were obtained. The effect of surface morphology of the substrate on homoepitaxial nucleation of GaN films prepared from ammonoacid solutions is investigated. Two-dimensional nucleation is obtained for substrates etched by hot concentrated KOH prior film growth. In this case the interface between film and the ( ) substrate does not show any signs of voids or island nucleation. Cracking pattern reveals similar mechanical-elastical properties for film and substrate.  相似文献   
66.
Lead and cadmium contents in cereals and pulses in north-eastern China   总被引:2,自引:0,他引:2  
It is known that, unlike Japanese, Koreans or southern Chinese who depend on rice as a major source of energy for daily life, people in north-eastern China rely not only on rice, but on wheat and other cereals and to a lesser extent also on pulses. Cereal and pulse samples were collected from open markets in north-eastern China, and analyzed by inductively-coupled plasma spectrometry (ICP-MS) for two potentially hazardous heavy metals — lead (Pb) and cadmium (Cd). The average Pb level in cereals (31.3 ng Pb/g as a geometric mean) and that of pulses (25.7 ng Pb/g) were similar to each other with no significant difference. Among the cereals, Pb contents were higher in foxtail millet (54.3 ng/g) and lower in maize (35.4 ng Pb/g; grain and flour in combination), wheat flour (28.8 ng Pb/g) and rice flour (22.7 ng Pb/g). Lead levels in two important types of pulses, kidney bean and soybean (24.6 and 30.8 ng Pb/g, respectively), were comparable to the levels in rice and wheat. In contrast, Cd levels were substantially higher in pulses (55.7 ng Cd/g) than in cereals (9.2 ng Cd/g), and among the pulses, Cd in soybean (55.7 ng Cd/g) was significantly higher than that in kidney bean (23.8 ng Cd/g). The possible public health implication of the Pb and Cd levels, especially the high Pb level in foxtail millet (54.3 ng Pb/g) and the high Cd level in soybean (73.5 ng Cd/g), is discussed.  相似文献   
67.
In early July 2018, record heavy rainfalls caused enormous damage from western Japan to the Tokai region. In particular, Hiroshima, Okayama, and Ehime Prefectures suffered extensive human casualties and tremendous damage to housing units and the infrastructure due to landslides and river flooding. The authors conducted a series of reconnaissance operations and analyzed various kinds of data, including rainfall records, aerial photographs, official statistics of the disasters, and topographical and geological maps of Ehime Prefecture. In this report, the authors focus on the rainfall characteristics, geological background, and landslide statistics and distributions associated with the July 2018 events, and present examples of typical damage by geological belt. Based on this, they discuss several characteristics of the landslides, including the rainfall thresholds by geological belt, the characteristics of the runout distance of the debris flows, and the rainfall thresholds for landslide initiation in terms of the Soil Water Index (SWI). Based on an official database of a total of 413 landslides occurring in Ehime Prefecture and the authors’ newly developed database of 883 landslides in the southern part of the prefecture, several findings were obtained, for example, that slopes in the Shimanto Belt had a lower rainfall threshold for landslide initiation than slopes in the other two geological belts, namely, Sambagawa and Chichibu Belts.  相似文献   
68.
Benchmark numerical solutions for a three-dimensional natural convection heat transfer problem in a cubical cavity are presented in this paper. The 3-D cavity has two differentially heated and isothermal vertical walls and also four adiabatic walls. The computations are conducted for three Rayleigh numbers of 104, 105 and 106. The filled fluid is with air and the Prandtl number is fixed at 0.71. The computed results are efficiently obtained by using the time-space method, which was proposed by Saitoh (1991) as a highly efficient and fast solver for general heat transfer and fluid flow problems. In our computations, the high-accuracy finite differences of a fourth-order were employed for the spatial discretization of governing equations and boundary conditions. In addition the third-order backward finite difference was used in timewise discretization. The resultant converged flow and temperature characteristics are also presented. The spatial grid dependency of the solutions was examined on a uniform grid. In addition, the grid-independent benchmark solutions were obtained by Richardson extrapolation for three cases. The present benchmark solutions will be useful for checking the performance and accuracy of any numerical methodologies.  相似文献   
69.
Shield Tunnel Construction in Centrifuge   总被引:3,自引:0,他引:3  
A large number of centrifuge model tests for simulating the shield construction process in dry sand was carried out by using a newly developed 100 mm diameter miniature shield tunnel. Different construction processes were modeled by three series of tests. A “buried tube test” was conducted to measure the lining stress under a centrifugal acceleration, a “tail void test” simulated the process of tail void formation only, and a “shield test” dealt with the complete process of shield construction. Lining stresses, transverse and longitudinal surface settlements, and earth pressures around the tunnel were simultaneously measured during advancement of the shield at a centrifugal acceleration of 25g. The lining stress at the crown elevation was well predicted by Terzaghi's loosening earth pressure. From the comparison with the recent field measurements and the comparative results of three series of tests, it was confirmed that the shield construction process was successfully simulated in a centrifuge. An experimental formula for estimating the surface settlement above the shield was deduced by a function of tail void thickness and cover-to-diameter ratio.  相似文献   
70.
In this paper, a new software defined radio platform with direct conversionisintroduced.The platform is named SOPRANO, which stands for Software Programmableand Hardware Reconfigurable Architecture for Network.Main features of SOPRANO include a high-level design methodologyfor digital circuits, direct conversion based on six-port technology, andnovel digital signal processingalgorithms for multi-band and multi-mode operation.The first prototype of the SOPRANO platform has been built and was ableto receive M-ary PSK (Phase Shift Keying)and QAM (Quadrature Amplitude Modulation) signals,with two different carrier frequencies at 2.45 GHz and 5.25 GHz,by changing signal-processing software.  相似文献   
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