Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al re...Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion reactors.At the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He reaction.The^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of Sciences.The neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb reaction.The measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature data.The newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental values.The obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.展开更多
Mg/Al mixed oxides with molar ratios of 2_6 of Mg to Al used as supports for platinum catalysts were obtained by the thermal decomposition method. The effect of the composition of the mixed oxides on the physicochemic...Mg/Al mixed oxides with molar ratios of 2_6 of Mg to Al used as supports for platinum catalysts were obtained by the thermal decomposition method. The effect of the composition of the mixed oxides on the physicochemical properties was studied by TPD, nitrogen sorption, XRD and TG-DTA characterization methods. The synthesis of o-phenylphenol(OPP) from a dimer(obtained from cyclohexanone condensation) was investigated over Pt/CHT catalysts and compared with those over Pt/MgO and Pt/Al 2O 3 catalysts. These catalysts show a high activity and selectivity for OPP, with a conversion reaching 93.8% and a selectivity reaching 87.9% in some experiments. For Pt/CHTx catalysts, the calcined hydrotalcites exhibited strong base sites, which were necessary to catalyze the synthesis of OPP.展开更多
Monometallic catalyst Pt/SAPO-11 was prepared by impregnation method.Bimetallic catalysts LaPt/SAPO-11 or CePt/SAPO-11 was prepared by sequential impregnation method.The catalysts were characterized by X-ray diffracti...Monometallic catalyst Pt/SAPO-11 was prepared by impregnation method.Bimetallic catalysts LaPt/SAPO-11 or CePt/SAPO-11 was prepared by sequential impregnation method.The catalysts were characterized by X-ray diffraction(XRD),nitrogen adsorption,temperature-programmed desorption of ammonia(NH3-TPD),and Fourier transform infrared spectroscopy(FT-IR) techniques.The results showed that with the addition of rare earths the BET surface areas,pore volume,the amount of Bronsted acid and the total acidity of catalys...展开更多
Platinum(Pt)supported on Zinc(Zn)modified silicalite-1(S-1)zeolite(denoted as Pt-Zn/S-1)was prepared by using a wetness-impregnation method and applied in the n-hexane aromatization reaction for the first time.Both Le...Platinum(Pt)supported on Zinc(Zn)modified silicalite-1(S-1)zeolite(denoted as Pt-Zn/S-1)was prepared by using a wetness-impregnation method and applied in the n-hexane aromatization reaction for the first time.Both Lewis and Bronsted acid sites were detected in Pt-Zn/S-1 catalyst by means of FT-IR adsorption of NH3 experiment,which were identified as mostly weak and medium ones.Besides,Pt and Zn species showed strong interaction,as revealed by the TPR(Temperature-programmed reduction)and XPS(X-ray photoelectron spectroscopy)experiments.Pt-Zn/S-1 catalyst exhibited excellent aromatization function rather than isomerization and cracking side reactions in the conversion of n-hexane.Pulse experimental study showed that 75.6%of n-hexane conversion and 76.8%of benzene selectivity were obtained over Pt0.1-Zn60/S-l catalyst at 550℃ and under atmospheric pressure.By spectroscopy tests and pulse experimental results,it was concluded that the n-hexane aromatization over Pt-Zn/S-1 catalyst follows a metal-acid bifunctional mechanism.Furthermore,with the assistance of Zn,the electron-deficient Pt species in Pt-Zn/S-1 showed good sulfur tolerance performance.展开更多
基金the Open Project of Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology(NLK 2022-04)the Central Government Guidance Funds for Local Scientific and Technological Development,China(No.Guike,ZY22096024)+1 种基金the National Natural Science Foundation of China(12065003)Guangxi Key R&D Project(2023AB07029).
文摘Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion reactors.At the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He reaction.The^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of Sciences.The neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb reaction.The measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature data.The newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental values.The obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.
基金The project was supported by the National Natural Science Foundation of China(21076197)Natural Science Foundation of Zhejiang Province, China(Y4090440)Qianjiang Talent Program of Zhejiang Province,China(2010R10038)~~
基金the financial supports from the National Natural Science Foundation of China(No.52065009)the Science and Technology Planning Project of Guizhou Province,China(No.ZK2021269)the Science and Technology Planning Project of Guiyang,China(No.2021.1-4)。
文摘Mg/Al mixed oxides with molar ratios of 2_6 of Mg to Al used as supports for platinum catalysts were obtained by the thermal decomposition method. The effect of the composition of the mixed oxides on the physicochemical properties was studied by TPD, nitrogen sorption, XRD and TG-DTA characterization methods. The synthesis of o-phenylphenol(OPP) from a dimer(obtained from cyclohexanone condensation) was investigated over Pt/CHT catalysts and compared with those over Pt/MgO and Pt/Al 2O 3 catalysts. These catalysts show a high activity and selectivity for OPP, with a conversion reaching 93.8% and a selectivity reaching 87.9% in some experiments. For Pt/CHTx catalysts, the calcined hydrotalcites exhibited strong base sites, which were necessary to catalyze the synthesis of OPP.
基金supported by the Foundation of Jiangsu Key Laboratory of Precious Metals Chemistry (SYGK0710)Natural Scientific Foundation of Jiangsu Teachers University of Technology (KYY06029)
文摘Monometallic catalyst Pt/SAPO-11 was prepared by impregnation method.Bimetallic catalysts LaPt/SAPO-11 or CePt/SAPO-11 was prepared by sequential impregnation method.The catalysts were characterized by X-ray diffraction(XRD),nitrogen adsorption,temperature-programmed desorption of ammonia(NH3-TPD),and Fourier transform infrared spectroscopy(FT-IR) techniques.The results showed that with the addition of rare earths the BET surface areas,pore volume,the amount of Bronsted acid and the total acidity of catalys...
基金financially supported by the National Natural Science Foundation of China (21603023)
文摘Platinum(Pt)supported on Zinc(Zn)modified silicalite-1(S-1)zeolite(denoted as Pt-Zn/S-1)was prepared by using a wetness-impregnation method and applied in the n-hexane aromatization reaction for the first time.Both Lewis and Bronsted acid sites were detected in Pt-Zn/S-1 catalyst by means of FT-IR adsorption of NH3 experiment,which were identified as mostly weak and medium ones.Besides,Pt and Zn species showed strong interaction,as revealed by the TPR(Temperature-programmed reduction)and XPS(X-ray photoelectron spectroscopy)experiments.Pt-Zn/S-1 catalyst exhibited excellent aromatization function rather than isomerization and cracking side reactions in the conversion of n-hexane.Pulse experimental study showed that 75.6%of n-hexane conversion and 76.8%of benzene selectivity were obtained over Pt0.1-Zn60/S-l catalyst at 550℃ and under atmospheric pressure.By spectroscopy tests and pulse experimental results,it was concluded that the n-hexane aromatization over Pt-Zn/S-1 catalyst follows a metal-acid bifunctional mechanism.Furthermore,with the assistance of Zn,the electron-deficient Pt species in Pt-Zn/S-1 showed good sulfur tolerance performance.
