The process of obtaining of high quality Mn-Zn, Mn-Cu and Mn-Cu-Zn alloy coatings from complexing ligands--citrate, EDTA （ethylene diaminetetra acetic acid） and nitrilotriacetic acid solutions was studied. Factors a...The process of obtaining of high quality Mn-Zn, Mn-Cu and Mn-Cu-Zn alloy coatings from complexing ligands--citrate, EDTA （ethylene diaminetetra acetic acid） and nitrilotriacetic acid solutions was studied. Factors affecting stability of solutions containing ligand or ligands and influence of electrolysis parameters： electrolyte composition, pH, cathodic current density on chemical composition of the obtained coatings, on their current efficiency, morphology and structure were investigated.展开更多
Based on excitation-resonance mass testing principle, a proper experiment testing system is designed for annular parts. The dynamics characters of the axis sleeve, which is made of a new Mn-Cu alloy and used as a vibr...Based on excitation-resonance mass testing principle, a proper experiment testing system is designed for annular parts. The dynamics characters of the axis sleeve, which is made of a new Mn-Cu alloy and used as a vibration reductor in high acceleration rotary testing machine for fusee, is investigated. The relationship between stiffness coefficient and utilizing frequency is obtained, and the simplified dynamics model of crystal is established From the viewpoint of crystal microstructure of the Mn-Cu alloy, the experiment result is analyzed by the viscoelastic theory, and the characters of stress and strain in the condition of high frequency are discussed. The results indicate that the Mn-Cu alloy annular parts are fit to be used on the high accleration rotary testing machine for fusee.展开更多
Zn-Mn-Cu/SC（U） sorbent was hydrothermally synthesized by ultrasound-assisted high-pressure impregnation method with semi-coke（SC）as support and the mixed solution of zinc nitrate,manganese nitrate and copper nitra...Zn-Mn-Cu/SC（U） sorbent was hydrothermally synthesized by ultrasound-assisted high-pressure impregnation method with semi-coke（SC）as support and the mixed solution of zinc nitrate,manganese nitrate and copper nitrate as active component precursors.The desulfurization performances of hot coal gas on the prepared sorbent at a mid-temperature of 500°C were tested in fixed-bed reactor.Morphology and pore structure of the prepared sorbent were also characterized by TEM,N2adsorption/desorption isotherms and XRD.For comparison,the sorbent of Zn-Mn-Cu/SC prepared by conventional high-pressure impregnation was also evaluated and characterized in order to study the effects of ultrasound treatment.Zn-Mn-Cu/SC（U） sorbent prepared by high-pressure impregnation under ultrasound-assisted condition showed a better desulfurization performance than Zn-Mn-Cu/SC.It could remove H2 S from 1000×10-6m3/m3 to 0.1×10-6m3/m3 at 500°C and maintained for 12.5 h with the sulfur capacity of 7.74%,in which both the breakthrough time and sulfur capacity were about 32% and 51% higher than those of Zn-Mn-Cu/SC sorbent.The introduction of ultrasound during high-pressure impregnation process greatly improved the morphology and pore structure of the sorbent.The ultrasonic treatment made particle size of active components smaller and made them more evenly disperse on semi-coke support,which provided more opportunities to contact with H2S in coal-based gases.However,there were no any difference in compositions and existing forms of active components on the Zn-Mn-Cu/SC and Zn-Mn-Cu/SC（U） sorbents.展开更多
Internal friction and elastic modulus of ternary Mn-Cu-Al alloys containing 56—60 wt-% Mn,0-3.59 wt-% Al were measured with acoustic frequency,1 kHz,in the tempera- ture range of-150 to 150℃.It was found that when t...Internal friction and elastic modulus of ternary Mn-Cu-Al alloys containing 56—60 wt-% Mn,0-3.59 wt-% Al were measured with acoustic frequency,1 kHz,in the tempera- ture range of-150 to 150℃.It was found that when the specimen was aged in the temperature range under the spinodal curve within the miscibility gap(400—500℃),the internal fric- tion increases with an increase of the aging time and reaches a maximum value at a certain ag- ing time which is shorter with a higher aging temperature.Two internal friction peaks which did not appear before the aging were observed above room temperature after a definite aging time.These are respectively the martensitic tranformation peak and the relaxation peak orig- inating from the stress-induced movement of the twin boundaries.The former peak shifts to- ward higher temperatures with an increase of the aging time,whereas the relaxation peak ap- pearing at 15℃,is independent of the aging time and temperature.The activation energy as- sociated with the relaxation peak was found to be 0.56 eV which is about the same as that of the relaxation peak in binary alloy containing 90 wt-% Mn.It was also found that the hardness,strength and the brittleness of the specimen increase when aged below the spinodal curve within the miscibility gap.The addition or Al enhances the strength but reduces the in- ternal friction of the specimen.A choice of suitable aging time and temperature can give an optimum compromise of high strength and high internal friction.Analysis of experimental re- sults suggests that spinodal decomposition leads to Mn-rich zones in the specimen and thus causes the phase transformation and the change of mechanical properties of the specimen.展开更多
文摘The process of obtaining of high quality Mn-Zn, Mn-Cu and Mn-Cu-Zn alloy coatings from complexing ligands--citrate, EDTA （ethylene diaminetetra acetic acid） and nitrilotriacetic acid solutions was studied. Factors affecting stability of solutions containing ligand or ligands and influence of electrolysis parameters： electrolyte composition, pH, cathodic current density on chemical composition of the obtained coatings, on their current efficiency, morphology and structure were investigated.
文摘Based on excitation-resonance mass testing principle, a proper experiment testing system is designed for annular parts. The dynamics characters of the axis sleeve, which is made of a new Mn-Cu alloy and used as a vibration reductor in high acceleration rotary testing machine for fusee, is investigated. The relationship between stiffness coefficient and utilizing frequency is obtained, and the simplified dynamics model of crystal is established From the viewpoint of crystal microstructure of the Mn-Cu alloy, the experiment result is analyzed by the viscoelastic theory, and the characters of stress and strain in the condition of high frequency are discussed. The results indicate that the Mn-Cu alloy annular parts are fit to be used on the high accleration rotary testing machine for fusee.
基金supported by the National Basic Research Program of China(2012CB723105)the National Natural Science Foundation of China(20976117)the Technological Innovation Programs of Higher Education Institutions in Shanxi(2013JYT113)
文摘Zn-Mn-Cu/SC（U） sorbent was hydrothermally synthesized by ultrasound-assisted high-pressure impregnation method with semi-coke（SC）as support and the mixed solution of zinc nitrate,manganese nitrate and copper nitrate as active component precursors.The desulfurization performances of hot coal gas on the prepared sorbent at a mid-temperature of 500°C were tested in fixed-bed reactor.Morphology and pore structure of the prepared sorbent were also characterized by TEM,N2adsorption/desorption isotherms and XRD.For comparison,the sorbent of Zn-Mn-Cu/SC prepared by conventional high-pressure impregnation was also evaluated and characterized in order to study the effects of ultrasound treatment.Zn-Mn-Cu/SC（U） sorbent prepared by high-pressure impregnation under ultrasound-assisted condition showed a better desulfurization performance than Zn-Mn-Cu/SC.It could remove H2 S from 1000×10-6m3/m3 to 0.1×10-6m3/m3 at 500°C and maintained for 12.5 h with the sulfur capacity of 7.74%,in which both the breakthrough time and sulfur capacity were about 32% and 51% higher than those of Zn-Mn-Cu/SC sorbent.The introduction of ultrasound during high-pressure impregnation process greatly improved the morphology and pore structure of the sorbent.The ultrasonic treatment made particle size of active components smaller and made them more evenly disperse on semi-coke support,which provided more opportunities to contact with H2S in coal-based gases.However,there were no any difference in compositions and existing forms of active components on the Zn-Mn-Cu/SC and Zn-Mn-Cu/SC（U） sorbents.
文摘Internal friction and elastic modulus of ternary Mn-Cu-Al alloys containing 56—60 wt-% Mn,0-3.59 wt-% Al were measured with acoustic frequency,1 kHz,in the tempera- ture range of-150 to 150℃.It was found that when the specimen was aged in the temperature range under the spinodal curve within the miscibility gap(400—500℃),the internal fric- tion increases with an increase of the aging time and reaches a maximum value at a certain ag- ing time which is shorter with a higher aging temperature.Two internal friction peaks which did not appear before the aging were observed above room temperature after a definite aging time.These are respectively the martensitic tranformation peak and the relaxation peak orig- inating from the stress-induced movement of the twin boundaries.The former peak shifts to- ward higher temperatures with an increase of the aging time,whereas the relaxation peak ap- pearing at 15℃,is independent of the aging time and temperature.The activation energy as- sociated with the relaxation peak was found to be 0.56 eV which is about the same as that of the relaxation peak in binary alloy containing 90 wt-% Mn.It was also found that the hardness,strength and the brittleness of the specimen increase when aged below the spinodal curve within the miscibility gap.The addition or Al enhances the strength but reduces the in- ternal friction of the specimen.A choice of suitable aging time and temperature can give an optimum compromise of high strength and high internal friction.Analysis of experimental re- sults suggests that spinodal decomposition leads to Mn-rich zones in the specimen and thus causes the phase transformation and the change of mechanical properties of the specimen.
