By introducing the Dirac δ-function and Pauli exclusion principle in the presence of superstrong magnetic fields (SMFs), we investigate the influence of SMFs on beta decay and the change rates of electron fraction ...By introducing the Dirac δ-function and Pauli exclusion principle in the presence of superstrong magnetic fields (SMFs), we investigate the influence of SMFs on beta decay and the change rates of electron fraction (CREF) of nuclides 56Fe, 62Ni, 64Ni and 6SNi in magnetars, which are powered by magnetic field energy. We find that the magnetic fields have a great influence on the beta decay rates, and the beta decay rates can decrease by more than six orders of magnitude in the presence of SMFs. The CREF also decreases by more than seven orders of magnitude in the presence of SMFs.展开更多
Three new caryophyllene sesquiterpenoids,cytosporinols A-C(1-3),have been isolated from solid cultures of Cytospora sp.The structures of 1-3 were elucidated primarily by NMR spectroscopy,and 3 was further confirmed by...Three new caryophyllene sesquiterpenoids,cytosporinols A-C(1-3),have been isolated from solid cultures of Cytospora sp.The structures of 1-3 were elucidated primarily by NMR spectroscopy,and 3 was further confirmed by X-ray crystallography.The absolute configurations of the C-11 secondary alcohol in 1 and the 6,8-diol moiety in 3 were deduced using the modified Mosher and Snatzke’s method,respectively.Compounds 2 and 3 showed moderate cytotoxicity against HeLa cells.展开更多
To achieve high-efficiency utilization of complex and unmanageable iron-containing minerals,the effects of oxygen enrichment on productivity,yield,flame front speed,exhaust gas peak temperature,and desulphurization re...To achieve high-efficiency utilization of complex and unmanageable iron-containing minerals,the effects of oxygen enrichment on productivity,yield,flame front speed,exhaust gas peak temperature,and desulphurization reaction of the vanadium-titanium magnetite sintering process as well as sinter tumble index and mineralogy were clarified,with oxygen enrichment concentrations ranging from 21 to 29 vol.%.Results indicated that with increasing the oxygen enrichment concentration from 21 to 27 vol.%,the flame front speed increased from 30.3 to 40.0 mm min^(-1),the yield enhanced from 72%to 77%,and the productivity augmented from 1.83 to 2.67t m^(-2)h^(-1);in the meantime,the tumble index was improved from 73.7%to 77.9%,and the exhaust gas peak temperature rose from 376.4 to 484.8℃.The main reason for the improvement in sintering properties was the increased combustibility of fuels and the generation of proper liquid phase that improved the permeability of the packed bed.The improved sinter strength is mainly due to the increase in the phase fraction of silico-ferrites of calcium and aluminium.In addition,oxygen enrichment sintering could significantly increase the desulphurization level of vanadium-titanium magnetite sinter and the rate of desulphurization reaction during sintering process.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 11565020)the Counterpart Foundation of Sanya (Grant No. 2016PT43)+2 种基金the Special Foundation of Science and Technology Cooperation for Advanced Academy and Regional of Sanya (Grant No. 2016YD28)the Natural Science Foundation of Hainan province (Grant No. 114012)the Natural Science Foundation of Jiangxi Province (Grant No. 20132BAB212005)
文摘By introducing the Dirac δ-function and Pauli exclusion principle in the presence of superstrong magnetic fields (SMFs), we investigate the influence of SMFs on beta decay and the change rates of electron fraction (CREF) of nuclides 56Fe, 62Ni, 64Ni and 6SNi in magnetars, which are powered by magnetic field energy. We find that the magnetic fields have a great influence on the beta decay rates, and the beta decay rates can decrease by more than six orders of magnitude in the presence of SMFs. The CREF also decreases by more than seven orders of magnitude in the presence of SMFs.
基金support from the National Natural Science Foundation of China(30925039)the Beijing Natural Science Foundation(5111003)+1 种基金the Ministry of Science and Technology of China(2009CB522300,2010ZX09401-403)the Chinese Academy of Sciences(KSCX2-EW-G-6).
文摘Three new caryophyllene sesquiterpenoids,cytosporinols A-C(1-3),have been isolated from solid cultures of Cytospora sp.The structures of 1-3 were elucidated primarily by NMR spectroscopy,and 3 was further confirmed by X-ray crystallography.The absolute configurations of the C-11 secondary alcohol in 1 and the 6,8-diol moiety in 3 were deduced using the modified Mosher and Snatzke’s method,respectively.Compounds 2 and 3 showed moderate cytotoxicity against HeLa cells.
基金funded by the National Natural Science Foundation of China(Nos.51974054 and 52174300)Natural Science Foundation of Chongqing,China(No.cstc2020jcyj-msxmX0583).
文摘To achieve high-efficiency utilization of complex and unmanageable iron-containing minerals,the effects of oxygen enrichment on productivity,yield,flame front speed,exhaust gas peak temperature,and desulphurization reaction of the vanadium-titanium magnetite sintering process as well as sinter tumble index and mineralogy were clarified,with oxygen enrichment concentrations ranging from 21 to 29 vol.%.Results indicated that with increasing the oxygen enrichment concentration from 21 to 27 vol.%,the flame front speed increased from 30.3 to 40.0 mm min^(-1),the yield enhanced from 72%to 77%,and the productivity augmented from 1.83 to 2.67t m^(-2)h^(-1);in the meantime,the tumble index was improved from 73.7%to 77.9%,and the exhaust gas peak temperature rose from 376.4 to 484.8℃.The main reason for the improvement in sintering properties was the increased combustibility of fuels and the generation of proper liquid phase that improved the permeability of the packed bed.The improved sinter strength is mainly due to the increase in the phase fraction of silico-ferrites of calcium and aluminium.In addition,oxygen enrichment sintering could significantly increase the desulphurization level of vanadium-titanium magnetite sinter and the rate of desulphurization reaction during sintering process.