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101.
Metallurgical and Materials Transactions A - Wetting transitions between molten metals and different solid substrates were investigated using the sessile drop method to evaluate the possibilities...  相似文献   
102.
The equilibrium state and crystal growth of (BEDT-TTF)2I3 were investigated. Measurements of the temperature dependence of solubility and analyses of the components in the solution were carried out. The analysis of the solution showed that the crystals decompose into neutral BEDT-TTF and I2 molecules. As to the polymorphism, it was clarified that the -form is more stable than the -form in the temperature region between 0 and 50 °C. Using these information, we succeed in growing single crystals form BEDT-TTF and I2 and in control of the crystallizing polymorph. The polymorphic behavior was explained in terms of supersaturation as a driving force of crystal growth.  相似文献   
103.
The vomeronasal organ (VNO) that preferentially detects species‐specific substances is diverse among animal species, and its morphological properties seem to reflect the ecological features of animals. This histological study of two female reticulated giraffes (Giraffa camelopardalis reticulata) found that the VNO is developed in giraffes. The lateral and medial regions of the vomeronasal lumen were covered with sensory and nonsensory epithelia, respectively. The vomeronasal glands were positive for periodic acid‐Schiff and alcian blue (pH 2.5) stains. The VNO comprises several large veins like others in the order Cetartiodactyla, suggesting that these veins function in a pumping mechanism in this order. In addition, numerous thin‐walled vessels located immediately beneath the epithelia covering the lumen entirely surrounded the vomeronasal lumen. This sponge‐like structure might function as a specific secondary pump in giraffes.  相似文献   
104.
The analytical results of blowdown characteristics and thrust forces were compared with the experiments, which were performed as pipe whip and jet discharge tests under the PWR LOCA conditions. The blowdown thrust forces were obtained by Navier-Stokes momentum equation for a single-phase, homogeneous and separated two-phase flow, assuming critical pressure at the exit if a crifical flow condition was satisfied.The following results are obtained:
1. (1) The node-junction method is useful for both the analyses of the blowdown thrust force and of the water hammer phenomena.
2. (2) The Henry-Fauske model for subcooled critical flow is effective for the analysis of the maximum thrust force under the PWR LOCA conditions. The jet thrust parameter of the analysis and experiment is equal to 1.08.
3. (3) The thrust parameter of saturated blowdown has the same one with the value under pressurized condition when the stagnant pressure is chosen as the saturated one.
4. (4) The dominant terms of the blowdown thrust force in the momentum equation are the pressure and momentum terms except that the acceleration term has large contribution only just after the break.

References

[1]M. Okazaki et al., Preprint of two phase flow meeting, JSME (1980), pp. 85–88 (in Japanese).[2]F.J. Moody, ASME 69HT31 (1969).[3]F.J. Moody, Fluid reaction and impingiment loads, Nuclear Power Plants (1973), pp. 219–261.[4]B.R. Strong and R.J. Baschiere, Nucl. Engrg. Des. 45 (1978), pp. 419–428. Abstract | PDF (543 K) | View Record in Scopus | Cited By in Scopus (0)[5]RELAP4/MOD5, ANCR-NUREG-1335 (1976).[6]PRTHRUST, Nuclear Service Co..[7]N. Miyazaki et al., Nucl. Engrg. Des. 64 (1981), pp. 389–401. Abstract | PDF (806 K) | View Record in Scopus | Cited By in Scopus (0)[8]W.H. Retting et al., IN-1321 (1970).[9]M. Hsu et al., Nucl. Technology 53 (1981), pp. 58–63.[10]R.E. Henry and H.K. Fauske, Journal of Heat Transfer, Trans. ASME, Ser. C93 (1971), pp. 179–187. Full Text via CrossRef[11]F.J. Moody, Journal of Heat Transfer, Trans. ASME, Ser. C93 87 (1965), pp. 134–142.[12]N. Miyazaki et al., 1981 Fall Meeting Reactor Phys. and Eng., At. Energy Soc. Japan, Paper D58 (1981) (in Japanese).[13]K. Namatame and K. Kobayashi, Journal of Heat Transfer, Trans. ASME, Ser. C 98 (1976), pp. 12–18. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (0)[14]M. Sobajima, Nucl. Sci. Engrg. 60 (1976), pp. 10–18. View Record in Scopus | Cited By in Scopus (0)[15]R.D. Jain and G.A. Hastings, Trans. Ame. Nucl. Soc. 21 (1975), pp. 345–346.  相似文献   
105.
An in situ experimental technique was developed for detecting structure changes at the electrode/electrolyte interface of lithium cell using synchrotron X-ray reflectometry and two-dimensional model electrodes with a restricted lattice plane. The electrode was constructed with an epitaxial film of LiNi0.8Co0.2O2 synthesized by the pulsed laser deposition method. The orientation of the epitaxial film depends on the substrate plane; the 2D layer of LiNi0.8Co0.2O2 is parallel to the SrTiO3 (1 1 1) substrate ((003)LiCo0.2Ni0.8O2//(111)SrTiO3), while the 2D layer is perpendicular to the SrTiO3 (1 1 0) substrate ((110)LiCo0.2Ni0.8O2//(110)SrTiO3). These films provided an ideal reaction field suitable for detecting structure changes at the electrode/electrolyte interface during the electrochemical reaction. The X-ray reflectometry indicated a formation of a thin-film layer at the LiNi0.8Co0.2O2 (1 1 0)/electrolyte interface during the first charge-discharge cycle, while the LiNi0.8Co0.2O2 (0 0 3) surface showed an increase in the surface roughness without forming the surface thin-film layer. The reaction mechanism at the electrode/electrolyte interface is discussed based on our new experimental technique for lithium batteries.  相似文献   
106.
Ozonated water was used for inactivation of Fusarium oxysporum conidia in sterilized water and inorganic soil-less nutrient medium at different treatment temperatures. F. oxysporum conidia were effectively inactivated in both water and nutrient media and the inactivation curves were almost same at 15°C, 25°C and 30°C. Approximate 4-log orders of F. oxysporum conidia were killed when the ozonated water with initial ozone concentration of 1.0 ppm had been used. The surviving curves, however, were characterized by a tailing-off effect, and the effect was related to the residual ozone concentration in the ozone treated suspensions.  相似文献   
107.
A new type of thermosetting resin can be obtained from solventless varnishes composed of polyfunctional isocyanates and epoxides. The IR spectra show that the cured resins have isocyanurate and oxazolidone rings in their chemical structure, hence their name, isocyanurate–oxazolidone resins. The viscoelastic behavior of the cured resins can be varied considerably by selecting an appropriate reactant species and changing the equivalent ratio of the isocyanate and epoxy groups in the varnishes. Three relaxations, labeled α, β, and γ, characterize their dynamic mechanical spectra. The α-dispersion is due to the glass transition, the β-dispersion, to local mode motions of the backbone chains of resins, and the γ-dispersion, to the molecular motions of long alkyl chains. If certain additives are mixed into the varnishes before curing, microphase separation takes place during the reactions. The resins finally obtained have a peculiar physical structure in which rubber particles are dispersed throughout a matrix phase as confirmed by scanning electron-microscopic analysis and viscoelastic behavior.  相似文献   
108.
Test results of a catalytically assisted combustor for a gas turbine   总被引:1,自引:0,他引:1  
A catalytically assisted ceramic combustor for a gas turbine was designed and tested to achieve low NOx emissions. This combustor is composed of a burner and a ceramic liner. The burner consists of an annular preburner, six catalytic combustor segments and six premixing nozzles, which are arranged in parallel and alternately. In this combustor system, catalytic combustion temperature is controlled under 1000 °C, premixed gas is injected from the premixing nozzles to the catalytic combustion gas and lean premixed combustion over 1300 °C is carried out in the ceramic liner. This system was designed to avoid catalyst deactivation at high temperature and thermal shock fracture of the ceramic honeycomb monolith of the catalyst. A 1 MW class combustor was tested using LNG fuel. Firstly, NOx emissions from the preburner were investigated under various pressure conditions. Secondly, two sets of honeycomb cell density catalysts and one set of thermally pretreated catalysts ware applied to the combustor, and combustion tests were carried out under various pressure conditions. As a result, it was found that the main source of NOx was the preburner, and total NOx emissions from the combustor were approximately 4 ppm (at 16% O2) at an adiabatic combustion temperature of 1350 °C and combustor inlet pressure of 1.33 MPa.  相似文献   
109.
Fine particles of Tio2 were prepared from titanyl sulfate solution by the Spray pyrolysis Method( SPM) The reaction tube was divided into four zones: drying, dehydration, pyrolysis 1 and pyrolysis 2 zones. Under various reaction temperature and carrier gas flow rate, the mean size and the size distribution of particles collected at different sampling positions along the axial direction of the reactor were compared. The effects of operating conditions of drying, dehydration and subsequent pyrolysis steps on the formation mechanism of Tio2 fine particles were discussed  相似文献   
110.
Organic matter of a peat core (3.60 m, 7428 years BP) collected from Rawa Danau, west Java, Indonesia, was analyzed to evaluate the early diagenetic fates of lignin in a tropical wetland and to reconstruct past vegetation and climate changes. Vertical profiles of (Ad/Al)v, (Ad/Al)s, and lambda(8) show that the lignin composition is well preserved in a sub-aqueous environment under reducing conditions. The sedimentary terrigenous plant material at Rawa Danau is comprised predominantly of angiosperm wood. For this kind of tropical, diverse, and dynamic ecosystem, a new vegetation change index called lignin phenol vegetation index (LPVI): LPVI is defined using the lignin phenol composition. This index can sensitively detect terrestrial vegetation changes as well as environmental conditions forcing such changes. The LPVI of the Rawa Danau peat core provides better resolution than other lignin parameters used previously, and reveals four major vegetation change events since the mid-late Holocene. In comparison to other geochemical data (i.e. elemental carbon, isotopes, and hydrocarbons), the LPVI is more sensitive and is able to trace even minor vegetation and climate changes and thus could improve biogeochemical interpretations of peat records.  相似文献   
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