Hydrous minerals in the subducting slabs are potential water carriers into the deep mantle,and thus the synthesis of new hydrous phases is significant in our understanding of water circulation throughout the Earth’s ...Hydrous minerals in the subducting slabs are potential water carriers into the deep mantle,and thus the synthesis of new hydrous phases is significant in our understanding of water circulation throughout the Earth’s interior.In this study,we report the two new hydrous phases,Al_(2)SiO_(6)H_(2)and Al_(5.5)Si_(4)O_(18)H_(3.5)(hereafter referred to simply as phases Psi and Phi,respectively),which are synthesized in the Al_(2)O_(3)-SiO_(2)-H_(2)O system at 15.5 GPa,1400℃and 17.5 GPa,1600℃ by using Sakura2500-ton multi-anvil apparatus.The luminescence spectra of Cr3+show the phase Psi has characteristic peaks at 687,693 and705 nm,while phase Phi has characteristic peaks at 691,696 and 708 nm.Single-crystal X-ray diffraction (SCXRD) refinements yield a monoclinic structure of both phases (space group P2_(1)) with ideal chemical formulae of Al_(2)SiO6H2and Al5.5Si4O18H3.5respectively.The determined lattice parameters for phase Psi are a=9.4168±0.0016Å,b=4.3441±0.0007Å,c=9.4360±0.002Åand β=119.726±0.005°at ambient pressure and 300 K,while the phase Phi has a=7.2549±0.0018Å,b=4.3144±0.001Å,c=8.0520±0.002Å,and β=101.740±0.009°at ambient pressure and 250 K.Electron microprobe analyses (EPMA) show the chemical compositions of phases Psi and Phi to be Al_(1.99)Si_(0.85)O_(6)H_(2.62)and Al_(5.58)Si_(2.81)O_(18)H_(8.03),respectively,which slightly deviate from the ideal formulae inferred from SCXRD measurements.This may result from the disorder or substitution of Al and Si by H in the crystal structures under our synthesis conditions.Our study suggests that phases Psi and Phi are the two potential water carriers at the upper part of the mantle transitions zone,providing new insights into how deep water is stored in this region.展开更多
Simultaneous equilibrium was applied to the thermodynamic analysis and calculation of Bi(Ⅲ)-X(Cl-, NO-3)-H2O systems, based on which the diagrams of the logarithm of equilibrium concentration of Bi(Ⅲ) of serie...Simultaneous equilibrium was applied to the thermodynamic analysis and calculation of Bi(Ⅲ)-X(Cl-, NO-3)-H2O systems, based on which the diagrams of the logarithm of equilibrium concentration of Bi(Ⅲ) of series precipitation vs pH value of these two systems at 25 ℃ were obtained, and the pH ranges of the stable zones of various precipitations were analyzed and determined. In Bi(Ⅲ)-Cl--H2O system, the variations of c0(Bi3+) and (c0(Cl-)) have little effect on the equilibria of Bi(OH)3-solution and BiOOH-solution, but has great influence on the (equilibrium) of BiOCl-solution. However, in Bi(Ⅲ)-NO-3-H2O system, the variations of c0(Bi3+) and c0(NO-3) have little effect on equilibria of Bi(OH)3-solution, BiOOH-solution and Bi2O3-solution. When pH value is high, Bi2O3 is the thermodynamic stable phase, its stable zone is the widest, almost including the stable zones of BiOCl or (BiONO3,) (Bi(OH)3) and BiOOH. Bi(OH)3 cannot be obtained from Bi(Ⅲ)-Cl--H2O system, even strong alkaline media. Bi2O3 can be obtained from the solution directly, and highly pure BiOCl or BiONO3 can also be obtained through strictly controlling pH value.展开更多
The ozone oxidation of endocrine disruptor bisphenol A in drinking water was investigated.A stainless completely mixed reactor was employed to carry out the degradation experiments by means of a batch model.With an in...The ozone oxidation of endocrine disruptor bisphenol A in drinking water was investigated.A stainless completely mixed reactor was employed to carry out the degradation experiments by means of a batch model.With an initial concentration of 11.0 mg/L,the removal efficiencies of BPA(bisphenol A)could be measured up to 70%,82%,and 90%when the dosages of ozone were 1,1.5,and 2 mg/L,respectively.The impacts on BPA degradation under the con-ditions of different ozone dosages,water background values,BPA initial concentrations,and ozone adding time were ana-lyzed.The results showed that ozone dosage plays a dominant role during the process of BPA degradation,while the impact of the contact time could be ignored.UV wavelength scan-ning was used to confirm that the by-products were produced,which could be absorbed at UV254.The value of UV254 was observed to have changed during the ozonation process.Based on the change of UV254,it could be concluded that BPA is not completely degraded at low ozone dosage,while shorter adding time of total ozone dosage,high ozone dosage,and improvement of dissolved ozone concentration greatly contribute to the extent of BPA degradation.The effects of applied H_(2)O_(2) dose in ozone oxidation of BPA were also examined in this study.The O_(3)-H_(2)O_(2) processes proved to have similar effects on the degradation of BPA by ozone oxidation.展开更多
We reported an unprecedented chemiluminescence(CL)behavior of polyamine-functionalized carbon dots induced by Fe^(3+)–H_(2)O_(2) Fenton-like system.The firststep CL intensity increased with the increasing of the conc...We reported an unprecedented chemiluminescence(CL)behavior of polyamine-functionalized carbon dots induced by Fe^(3+)–H_(2)O_(2) Fenton-like system.The firststep CL intensity increased with the increasing of the concentration of H_(2)O_(2) and Fe^(3+),when the Fe^(3+)concentration came to 10^(−3) M,the unprecedented two-step CL behavior appeared.The CL intensity of BPEI-CDs induced by Fenton-like system was about 10 times stronger than that of naked CDs.The possible two-step CL mechanism was speculated based on the photoluminescence spectra,CL emission spectra,and the effects of radical scavengers on the CL intensity.Radiative recombination of the injected holes by strong oxidant perferrate formed through Fe^(3+)–H_(2)O_(2) reaction and the;OH generated from successive Fenton reaction with the thermally excited electrons was proposed,which further facilitate full understanding about the optical properties of carbon dots.展开更多
基金supported by the Special Research Fund for the Doctoral Program of Tongren University(Grant No.trxyDH2201)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB42000000)the National Key Research and Development Program of China(Grant No.2019YFA0708502)。
文摘Hydrous minerals in the subducting slabs are potential water carriers into the deep mantle,and thus the synthesis of new hydrous phases is significant in our understanding of water circulation throughout the Earth’s interior.In this study,we report the two new hydrous phases,Al_(2)SiO_(6)H_(2)and Al_(5.5)Si_(4)O_(18)H_(3.5)(hereafter referred to simply as phases Psi and Phi,respectively),which are synthesized in the Al_(2)O_(3)-SiO_(2)-H_(2)O system at 15.5 GPa,1400℃and 17.5 GPa,1600℃ by using Sakura2500-ton multi-anvil apparatus.The luminescence spectra of Cr3+show the phase Psi has characteristic peaks at 687,693 and705 nm,while phase Phi has characteristic peaks at 691,696 and 708 nm.Single-crystal X-ray diffraction (SCXRD) refinements yield a monoclinic structure of both phases (space group P2_(1)) with ideal chemical formulae of Al_(2)SiO6H2and Al5.5Si4O18H3.5respectively.The determined lattice parameters for phase Psi are a=9.4168±0.0016Å,b=4.3441±0.0007Å,c=9.4360±0.002Åand β=119.726±0.005°at ambient pressure and 300 K,while the phase Phi has a=7.2549±0.0018Å,b=4.3144±0.001Å,c=8.0520±0.002Å,and β=101.740±0.009°at ambient pressure and 250 K.Electron microprobe analyses (EPMA) show the chemical compositions of phases Psi and Phi to be Al_(1.99)Si_(0.85)O_(6)H_(2.62)and Al_(5.58)Si_(2.81)O_(18)H_(8.03),respectively,which slightly deviate from the ideal formulae inferred from SCXRD measurements.This may result from the disorder or substitution of Al and Si by H in the crystal structures under our synthesis conditions.Our study suggests that phases Psi and Phi are the two potential water carriers at the upper part of the mantle transitions zone,providing new insights into how deep water is stored in this region.
文摘Simultaneous equilibrium was applied to the thermodynamic analysis and calculation of Bi(Ⅲ)-X(Cl-, NO-3)-H2O systems, based on which the diagrams of the logarithm of equilibrium concentration of Bi(Ⅲ) of series precipitation vs pH value of these two systems at 25 ℃ were obtained, and the pH ranges of the stable zones of various precipitations were analyzed and determined. In Bi(Ⅲ)-Cl--H2O system, the variations of c0(Bi3+) and (c0(Cl-)) have little effect on the equilibria of Bi(OH)3-solution and BiOOH-solution, but has great influence on the (equilibrium) of BiOCl-solution. However, in Bi(Ⅲ)-NO-3-H2O system, the variations of c0(Bi3+) and c0(NO-3) have little effect on equilibria of Bi(OH)3-solution, BiOOH-solution and Bi2O3-solution. When pH value is high, Bi2O3 is the thermodynamic stable phase, its stable zone is the widest, almost including the stable zones of BiOCl or (BiONO3,) (Bi(OH)3) and BiOOH. Bi(OH)3 cannot be obtained from Bi(Ⅲ)-Cl--H2O system, even strong alkaline media. Bi2O3 can be obtained from the solution directly, and highly pure BiOCl or BiONO3 can also be obtained through strictly controlling pH value.
基金This work was completed with help from all members of the project team led by Professor GAO Naiyun.This work was supported by the National High-Tech Research and Development(863)Program of China(Grant No.2002AA649410)the Basic Science Research Program of Shanghai(Grant No.05JC14059)+1 种基金the Excellent Young Teachers Program of Tongji UniversityThis work belongs to the open pro- gram of the state key laboratory of pollution control and resources reuse (PCRRF05007), Tongji University.
文摘The ozone oxidation of endocrine disruptor bisphenol A in drinking water was investigated.A stainless completely mixed reactor was employed to carry out the degradation experiments by means of a batch model.With an initial concentration of 11.0 mg/L,the removal efficiencies of BPA(bisphenol A)could be measured up to 70%,82%,and 90%when the dosages of ozone were 1,1.5,and 2 mg/L,respectively.The impacts on BPA degradation under the con-ditions of different ozone dosages,water background values,BPA initial concentrations,and ozone adding time were ana-lyzed.The results showed that ozone dosage plays a dominant role during the process of BPA degradation,while the impact of the contact time could be ignored.UV wavelength scan-ning was used to confirm that the by-products were produced,which could be absorbed at UV254.The value of UV254 was observed to have changed during the ozonation process.Based on the change of UV254,it could be concluded that BPA is not completely degraded at low ozone dosage,while shorter adding time of total ozone dosage,high ozone dosage,and improvement of dissolved ozone concentration greatly contribute to the extent of BPA degradation.The effects of applied H_(2)O_(2) dose in ozone oxidation of BPA were also examined in this study.The O_(3)-H_(2)O_(2) processes proved to have similar effects on the degradation of BPA by ozone oxidation.
基金the National Key Research and Development Program of China(2016YFA0203102)the Chinese Academy of Sciences(XDB14040100)the National Natural Science Foundation of China(Nos.21677152 and 21177138).
文摘We reported an unprecedented chemiluminescence(CL)behavior of polyamine-functionalized carbon dots induced by Fe^(3+)–H_(2)O_(2) Fenton-like system.The firststep CL intensity increased with the increasing of the concentration of H_(2)O_(2) and Fe^(3+),when the Fe^(3+)concentration came to 10^(−3) M,the unprecedented two-step CL behavior appeared.The CL intensity of BPEI-CDs induced by Fenton-like system was about 10 times stronger than that of naked CDs.The possible two-step CL mechanism was speculated based on the photoluminescence spectra,CL emission spectra,and the effects of radical scavengers on the CL intensity.Radiative recombination of the injected holes by strong oxidant perferrate formed through Fe^(3+)–H_(2)O_(2) reaction and the;OH generated from successive Fenton reaction with the thermally excited electrons was proposed,which further facilitate full understanding about the optical properties of carbon dots.