The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscope （SEM）, and energy disperse ...The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscope （SEM）, and energy disperse spectroscopy （EDS）. The experimental results showed that the a-A1 and eutectic Si crystals were modified with the addition of 0.3 wt% La. The eutectic Si crystals showed a granular distribution. At the same time, the alloy possessed the best mechanical property. When more than 0.3 wt% La was added to ADC12 aluminum alloy, the microstructure of as-cast alloy was coarsening gradually with the increase of the content of La and the mechanical property decreased. The effect of rare earth La which was added in ADC 12 A1-Alloy for up to 0.9 wt% had been investigated in this study. The dendrites ofADC12 Al-alloy was refined obviously and the morphology of Si crystals showed a particle structure when the addition of La reached 0,3 wt%. Besides, the acicular La-rich intermetallics in the alloy deteriorated the mechanical property of alloy： To avoid this unwanted phase, the amount of added rare earth La must be less than 0.6 wt%.展开更多
Kinetic and conductivity of new Schiff bases compounds such （（12Z）N-（5Z）-1-bromo-5-（phenylimino）-1H- pyrrol-2（5 H）-ylidene）benzenamine {ArN（CNBrCCHCH）NAr} （Ar = C6H5） incorporating the chelating diamino ...Kinetic and conductivity of new Schiff bases compounds such （（12Z）N-（5Z）-1-bromo-5-（phenylimino）-1H- pyrrol-2（5 H）-ylidene）benzenamine {ArN（CNBrCCHCH）NAr} （Ar = C6H5） incorporating the chelating diamino has been studied in this paper and was found a second order of this reaction. Electronic Properties using hyperchem program study has been improved for this compound such angel and bond distance, and then this compound was defining as electric conductivity and did prove to be useful for conduclively compound.展开更多
The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with ...The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with α-Co phase from 1 000 to 1 200 ℃.The Co3Ti phase possesses a solubility of Ta higher than 10%,and the addition of Ta stabilizes the Co3Ti phase.The isothermal sections of the Co-Ti-Ta system in the Co-rich region at 1 000,1 100 and 1 200 ℃ were constructed according to the result.展开更多
The magnetic refrigeration(MR)utilizing magnetocaloric effect(MCE)has been recognized as an environmentally friendly and energy efficiency technology.Here we presented the magnetic properties and MCE in Pr-doped La_(1...The magnetic refrigeration(MR)utilizing magnetocaloric effect(MCE)has been recognized as an environmentally friendly and energy efficiency technology.Here we presented the magnetic properties and MCE in Pr-doped La_(1-x)Pr_(x)Fe_(12)B_(6)(x=0.05-0.2)itinerant-electron metamagnetic(IEM)compounds.A small amount of Pr doping La site can greatly improve the peak values in the magnetic entropy change S_(M)(T)curves,especially under relatively low magnetic field changes(ΔH).Additionally,the peak temperature increases gradually and the magnetic hysteresis reduces gradually with increasing x.The observed MCE in present La_(1-x)Pr_(x)Fe_(12)B_(6)compounds is related to its field-induced first-ordered IEM transition.The peak values ofΔS_(M)for La_(1-x)Pr_(x)Fe_(12)B_(6)compounds reach 13.4,15.4,12.5 and 13.0 J/(kg K)at T_(C)~58,68,72and 89 K for x=0.05,0.10,0.15 and 0.2 under H of 0-7 T,respectively.The corresponding relative cooling power values are 462.3,480.7,372.4 and 375.7 J/kg.The present La_(1-x)Pr_(x)Fe_(12)B_(6)compounds could be good candidates for active MR application if the magnetic and thermal hysteresis can be further reduced.The present work indicates that the La Fe_(12)B_(6)-based material system could also exhibit promising magnetocaloric performances.展开更多
Based on the binding mode for hydrouracil in photosystem II (PS II) Dl protein, a general method for the solid phase combinatorial synthesis of hydrouracil library was developed. The acryloyl chloride or acid were cou...Based on the binding mode for hydrouracil in photosystem II (PS II) Dl protein, a general method for the solid phase combinatorial synthesis of hydrouracil library was developed. The acryloyl chloride or acid were coupled to Wang resin1 to afford the acryloyl ester2. Resin bound ester2 reacted with various primary amines to give secondary amines3, which were converted to the resin bound ureas4 by treatment with isocyanates. Preparation of the hydrouracils5 was achieved by the acidic cyclization-cleavage from the resin. For characterization purposes,8 hydrouracil analogues were synthesized in parallel, following which a small library of9 hydrouracil derivatives was prepared after cleavage from Wang resin. All the9 bydrouracil derivatives desired were identified by GCMS.展开更多
基金Supported by the National Natural Science Foundation of China(No.51165032)the Innovative Group of Science and Technology of College of Jiangxi Province(No.00008713)
文摘The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscope （SEM）, and energy disperse spectroscopy （EDS）. The experimental results showed that the a-A1 and eutectic Si crystals were modified with the addition of 0.3 wt% La. The eutectic Si crystals showed a granular distribution. At the same time, the alloy possessed the best mechanical property. When more than 0.3 wt% La was added to ADC12 aluminum alloy, the microstructure of as-cast alloy was coarsening gradually with the increase of the content of La and the mechanical property decreased. The effect of rare earth La which was added in ADC 12 A1-Alloy for up to 0.9 wt% had been investigated in this study. The dendrites ofADC12 Al-alloy was refined obviously and the morphology of Si crystals showed a particle structure when the addition of La reached 0,3 wt%. Besides, the acicular La-rich intermetallics in the alloy deteriorated the mechanical property of alloy： To avoid this unwanted phase, the amount of added rare earth La must be less than 0.6 wt%.
文摘Kinetic and conductivity of new Schiff bases compounds such （（12Z）N-（5Z）-1-bromo-5-（phenylimino）-1H- pyrrol-2（5 H）-ylidene）benzenamine {ArN（CNBrCCHCH）NAr} （Ar = C6H5） incorporating the chelating diamino has been studied in this paper and was found a second order of this reaction. Electronic Properties using hyperchem program study has been improved for this compound such angel and bond distance, and then this compound was defining as electric conductivity and did prove to be useful for conduclively compound.
基金Project (50771027) supported by the National Natural Science Foundation of China
文摘The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with α-Co phase from 1 000 to 1 200 ℃.The Co3Ti phase possesses a solubility of Ta higher than 10%,and the addition of Ta stabilizes the Co3Ti phase.The isothermal sections of the Co-Ti-Ta system in the Co-rich region at 1 000,1 100 and 1 200 ℃ were constructed according to the result.
基金supported by the National Natural Science Foundation of China(No.91963123)the Ten Thousand Talents Plan of Zhejiang Province of China(No.2018R52003)。
文摘The magnetic refrigeration(MR)utilizing magnetocaloric effect(MCE)has been recognized as an environmentally friendly and energy efficiency technology.Here we presented the magnetic properties and MCE in Pr-doped La_(1-x)Pr_(x)Fe_(12)B_(6)(x=0.05-0.2)itinerant-electron metamagnetic(IEM)compounds.A small amount of Pr doping La site can greatly improve the peak values in the magnetic entropy change S_(M)(T)curves,especially under relatively low magnetic field changes(ΔH).Additionally,the peak temperature increases gradually and the magnetic hysteresis reduces gradually with increasing x.The observed MCE in present La_(1-x)Pr_(x)Fe_(12)B_(6)compounds is related to its field-induced first-ordered IEM transition.The peak values ofΔS_(M)for La_(1-x)Pr_(x)Fe_(12)B_(6)compounds reach 13.4,15.4,12.5 and 13.0 J/(kg K)at T_(C)~58,68,72and 89 K for x=0.05,0.10,0.15 and 0.2 under H of 0-7 T,respectively.The corresponding relative cooling power values are 462.3,480.7,372.4 and 375.7 J/kg.The present La_(1-x)Pr_(x)Fe_(12)B_(6)compounds could be good candidates for active MR application if the magnetic and thermal hysteresis can be further reduced.The present work indicates that the La Fe_(12)B_(6)-based material system could also exhibit promising magnetocaloric performances.
文摘Based on the binding mode for hydrouracil in photosystem II (PS II) Dl protein, a general method for the solid phase combinatorial synthesis of hydrouracil library was developed. The acryloyl chloride or acid were coupled to Wang resin1 to afford the acryloyl ester2. Resin bound ester2 reacted with various primary amines to give secondary amines3, which were converted to the resin bound ureas4 by treatment with isocyanates. Preparation of the hydrouracils5 was achieved by the acidic cyclization-cleavage from the resin. For characterization purposes,8 hydrouracil analogues were synthesized in parallel, following which a small library of9 hydrouracil derivatives was prepared after cleavage from Wang resin. All the9 bydrouracil derivatives desired were identified by GCMS.
