Abstract: For the breaking phenomenon of mining axial-flow fanner's blades, based on the fundamentals of modal analysis, the measuring method of the blade's modal parameters and frequency modulation method of the blade are put forward,and the modal analysis of 70B2 Axial-Flow Fanner's blade is completed.
Abstract: Thermoplasticity of Fe-Mn-Si shape memory alloys has been investigated. The experimental results show that the shape memory effect (SME) increases but thermoplasticity decreases with the increasing of Silicon content in Fe-Mn-Si shape memory alloys. Thermoplasticity of these alloys can be improved apparently but SEM not be devastated by adding of microelement Magnesium, because of thermoplasticity being improved by adding of microelement Magnesium.Fe-Mn-Si alloys with 4% Silicon content can be rolled successfully to be seamless steel pipes. So Fe-Mn-Si shape memory alloys show a good applied prospect.
Abstract: The Mallat's Algorithm in wavelet transforms is used to preprocess the chinese speech signal. By decomposing the speech signal, the compression ratios is improved under the certain distortion degree. The theory of wavelet transforms and the Mallat's Algorithm are proposed and the method is verified by the experimental results.
Abstract: The reliability and suitability of EAM potentials can be identified by making a numerical calculation from the point of the view of mechanical stability of cubic crystals under uniaxial external force,the general theory of the mechanical stability is presented letter.Using the numerical method the theoretical strength,corresponding strain,atom cohesive energy,and elastic constants of the crystals can be also obtained.
Abstract: Investigate the aging dynamics of HSLA100 steel by hardness measurement and TEM observation. The results indicate that aging dynamics of HSLA100 can be discribed by Avrami equation. The apparent activation energy for the aging process is 140 kJ/mol, which has been reduced by the presence of excess vacances and high dislocation density. Also it has been proved that the coarsening process of ε-Cu obeys the Ostwald mechanism.
Abstract: Analyzes two basic control modes of hot strip mill AGC system:GM mode and X-ray monitor mode, uncovers the conflict between GM and X-ray monitor modes and its harmful effects for thickness error elimination, and gives the new concept of AGC weak control area and its basic characteristics.
Abstract: Reverse Monte Carlo Computer(RMC), simulation is introduced in defail, and a brief comment is given. Application of RMC is also introduced by way of an example.
Abstract: The redox process of Nb(V) in (K2NbF2) in FLINAK melt has been by studied using chronopotentiometry and chronoamperometry. The results show that the electrochemical reduction of Nb(V) in FLINAK melt goes through an electrochemical-chemical-electrochemical reaction(ECE) process. The electrochemical reaction of Nb (V) in FLINAK melt is a mono-electron and four-electron transfer process.
Abstract: It has been shown by cyclic voltammetry that the electrodeposition of Al-Mn alloys was affected significantly by the coneentration of MnCl2 and temperature. A single amorphous Al-Mn phase would be formed preferentially at higher concentrations of MnCL2 and lower temperatures. It has also been shown by potential step that the nucleatin rate was small and the growth seemed to be 2-dimensional during the elctrodeposition of amorphous Al-Mn, leading to quality electroplates with few defects.
Abstract: The property of superconducting phase transition of the high Tc superconductor RBa2Cu3Oy (R:most rare earth elements) was investigated. The conclusion was drawn that the phase transition changed from first order in magnetic field to second order in non-magnetic field. The representation of the Gibbs free energy of the superconductor RBa2Cu3Oy at the superconducting-normla state transition in non-magnetic field was derived.
Abstract: The mechanism of the electrochemical reduction of Ti(Ⅳ) and B(Ⅲ) as well as the electrochemical synthesis of TiB2 on platinum and molybdenum electrode in molten Li-NaF-K2TiF6-KBF4 system has been investigated for the first time by. Means of cyclic voltammetry. The electrodeposited coating has been analysed by X-ray diffraction. The results show that the electrolytic codeposition of titanium and boron with the formation of TiB2 can be achieved at molar ratios B/Ti>2.
Abstract: Monocrystalline dislocation-free silicon is grown by FZ in pure hydrogen atmosphere. Defects including microdefects can not be observed in as-grown monocrystalline dislocation-free silicon afteretching. But hydrogen induced defects and microdefects in FZ(H) Si will be always observed as FZ(H) Si rod after annealing. In order to remove the hydrogen induced defects and microdefects, the as-grown FZ(H) Si rod had to cut into the wafer which thickness is less than 1mm or NTD FZ(H) Si wafer is treatmented at the 940℃/0.5h. The qualified ratio was greater than 80% in the application of msnufacturing thyristors.
Abstract: Leaching galena concentrate with ferric chloride solution has been made using a orthogonal array to arrange experiments. The main factors of affecting leaching ratio have been found. The optimum process conditions were given.Simultaneously, the fused-salt electrolysis for production metal lead with leaching product lead chloride has been investigated. Experiments show that the new process of the leaching-fused salts electrolysis for making lead is presented.
Abstract: The properties of hard chromium plating in trihydric chromate bath has been studied. The content of carbon in the plating is about 4%, and the plating is noncrystalline. After the plating is heat treated, its Vickers hardness more then 1600.
Abstract: The process and principle to refine and alloy the secondary lead are proposed. Low-antimony alloy of lead-acid storage battery can be made from treated secondary lead. The high-antimony alloy, regular low-antimony alloy and secondary lead Low-antimony alloy have been compared in different experiments. Because some elements such as antimony, copper and bismuth are fully utilized in Low-antimony alloy based on secondary lead. This alloy has a low cost and good properties of casting, corrosion resistance, tensile strength and electricity.
Abstract: FeS2 (pyrite) were synthesized by pressure method in solution. The effect of pressure and PH on the FeS2 was studied and the possible mechanism of reaction was proposed. The utilization of FeS2 was measured.
Abstract: The anodic behavior of Ni in the LiCl-KCl eutectic melt saturated with Li2S was studied by using cyclic voltammetry. Several sulfides can be formed in the anodic process and it was controlled by diffusion. The anodic current was nearly a constant in the potential range from -1.2 to 0.1V vs Ag|AgCl.
Abstract: The technological process of separating Fe(Ⅲ) from rare-earth sulphate leaching selection originated in Baotou rare-earth mine with solvent extraction method has been obtained. The rate of recovery of rare-earth is more then 99%. The content of Fe(Ⅲ) is less than 0.11g/l in the solution after being separated. The 10% loss of rareearth which is resulted from coprecipitation of rare-earth with Fe(Ⅲ) in the process of separatiag femc ion with sediment method is avoided. The composition of extracted complex determined as well.
Abstract: Introduced measuring results and reliability of relaxation and crystallization in amorphous alloys by stretch expansion method combinning with the test results of resistance and X-ray diffraction,certain important conclusion is obtained.
Abstract: The highly sensitive colour system of Selenium (Ⅳ)-Potassium iodide-Malachite green was studied. The optimum conditions of this system using spectrophotometry were determined, and the reaction mechanism was discussed. It is feasible to use this method at room temperature. Both of the sensetivity and reproducibility are satisfactory. The molar absorptivity is 1.2 × 105 1 · mol-1· cm-1.Beer's law is obeyed in the range of 0~0.32μg/ml. It has been successfully used in determinining the trace selenium presented in water.
Abstract: The work load and restrain condition of power shovel's boom and long arm are determined. Then, the method of finite element which are plate element and three-dimensional isoparamenter element is used to analyse the stress distribution.
Abstract: The contents of trace Nb in low alloy steels have been determined by using photometric method of a complex compound derived from the reaction between Nb and 3, 5-dibromo -PADAP-tar in the range of pH 1.0~4.0. The experimental results show that it is more accuracy and reliable comparing with other testing methods.
Monthly, started in 1955 Supervising institution：Ministry of Education Sponsoring Institution：University of Science and Technology Beijing Editorial office：Editorial Department of Chinese Journal of Engineering Publisher：Science Press Chairperson：Ren-shu Yang Editor-in-Chief：Ai-xiang Wu ISSN 2095-9389CN 2095-9389
