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Toluene was decomposed in a surface discharge plasma reactor packed with various zeolites. The positioning effect of the zeolite bed was also investigated Reactor-B, in which the zeolite bed was located upstream, performed much better than Reactor-A, in which the zeolite bed was located downstream. Furthermore, the decomposition efficiency in Reactor-B increased with the capacity for toluene adsorption on zeolite, while that in Reactor-A did not. The toluene adsorbed in micropores was not decomposed effectively by direct electron impact, but was decomposed by active oxygen species generated in the plasma zone on the zeolite surface. A good correlation was also observed between toluene decomposition and ozone consumption in the downward-type reactor.  相似文献   
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The tracer diffusivities of calcium and iron in a steel-making slag of 33 pct CaO-27 pct SiO2-40 pct Fe2O3 by charge composition have been measured at 1360 to 1460°C as a function of temperature and oxygen pressure in the gas phase. The results expressed in cm2/s (in SI unit of m2/s, the following equation should be divided by 10,000) are given by $$D^{tr} = D_0 \left[ {P_{O_2 } } \right]^{1/\chi } \exp \left[ { - \frac{E}{{RT}}} \right](at 1360 to 1460^\circ C)$$ where for tracer diffusion of iron, Do is 0.2,x is 8.5, andE is 26 kcal/mol (1.09 x 104 J/ mol) and for tracer diffusion of calcium, Do is 0.1,x is 12.5, andE is 28 kcal/mol (1.17 × 104 J/mol). Prior to diffusion runs, the slag was equilibrated with the gas mixture of carbon monoxide and dioxide with an oxygen pressure of 10?11 to 10?8 atm. The diffusivity was measured by the instantaneous plane source method, using radioactive tracers of calcium and iron. The increase of the tracer diffusivities with the oxygen pressure was interpreted in relation to a probable increase of the divalent cation vacancies in the slag.  相似文献   
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Mechanochemical modification of previously synthesized LaFeO3 perovskite‐type oxide by a high‐energy ball milling was investigated to introduce Fe4+ ions or transform some Fe3+ into Fe4+ in LaFeO3. X‐ray absorption fine structure studies revealed that the formation of Fe4+ ions into LaFeO3 perovskite has been achieved at first time by ball milling at room temperature without any additives or replacement of La3+ ions by some divalent cations. The structural model of Fe4+ containing LaFeO3 could be described as with a modified perovskite having equal amounts of La and Fe vacancies, which is supported by a good correlation between the results of Fe K‐edge XANES spectra and O2‐TPD. The synthesis of Fe4+‐containing LaFeO3 perovskite by ball milling was able to produce the O2 adsorption capacity of nonsubstituted perovskite‐type oxide.  相似文献   
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Welding processes used in transport system manufacturing, such as the automotive industry, have in recent years seen a pronounced trend towards fabrication of lower-cost welded structures through efficiency enhancement focused on weld quality improvement. In this context, arc welding processes providing sufficient weld reinforcing ability, while allowing higher-speed welding are expected to emerge. In welding of aluminium alloys, MIG welding conferring superior economy and profitability holds out particularly high expectations, in future set to be the mainstream process for fabrication of welded structures. In MIG welding, however, straightforward adoption of higher welding speeds for efficiency enhancement purposes leads to loss of joint quality and weldpool turbulence due to increased current. Welding speeds therefore normally have an upper limit of around 1.5 m/min.1 More recently, however, further welding speed increases have been sought through improvement of wire feed1 and power supply2 systems.  相似文献   
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A series of (vinylphenyl)pyridine‐based polymer binders, PVPh2Py, PVPh3Py, and PVPh4Py, are designed and synthesized and it is found that mixtures of Liq and the polymers exhibit superior electron injection characteristics as ultrathin (1.6 nm) electron injection layer (EIL) films. They are comparable to those of EILs composed only of Liq. The addition of the polymers does not deteriorate the performance of Liq EILs. Additionally, when the EIL thickness is increased from 1.6 nm to 16 nm, the driving voltages increase and the external quantum efficiencies decrease. The increase in the voltage and decrease in the EQE are suppressed in the device with mixed EILs compared to those observed for the device composed of 100 wt% Liq. Furthermore, the position of the nitrogen in the pyridine ring is considered to influence the electron transport properties of the EILs. The mixing PVPh4Py with Liq improves the driving voltage of the fabricated devices, even with a thick mixed EIL. This reduced dependence of the performance of EILs on their thickness will be advantageous for the coating of large areas using solution processes.  相似文献   
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Neues Verfahren zur Herstellung von großen Wüstitkristallen. Erörterung der Reaktionen zwischen Wüstit und Kalk-Kieselsäure-Gemischen. Deutung des Bildungsmechanismus im Primärschlackegebiet durch Erläuterung des Aufbaus hohler Körper aus reduzierten Eisenoxiden in Eiszapfenformen.  相似文献   
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The rate of the chemical potential change of oxygen in a liquid PbO?SiO2 binary solution, with SiO2 contents of 10, 20, and 30 mol pct, and in pure PbO, has been measured at temperatures of 900°, 950°, 1000°, 1050°, and 1100°C. The rate increased with temperature according to the Arrhenius type relation and decreased with the increase of the silica content. It is suggested that the rate-controlling step is the counter diffusion rate of Pb2+ and Pb4+ ions, which are considered to be the most easily movable ions in the PbO?SiO2 solution. The relation between the rate of oxygen chemical potential change and the electrical conductivity is also discussed for the liquid PbO?SiO2 system.  相似文献   
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