The rates of electron exchange between oxidized and reduced forms of sev- eral derivatives of ferrocene(1-3)have been measured in acetonitrile by the NMR line h(?)oadening method at 25℃。It was found that the r(?)tes...The rates of electron exchange between oxidized and reduced forms of sev- eral derivatives of ferrocene(1-3)have been measured in acetonitrile by the NMR line h(?)oadening method at 25℃。It was found that the r(?)tes vary with the lengtn of the substitutent chain and the potential of E_(Fe(Ⅲ)/Fe(Ⅱ))in the ferrocene derivatives.展开更多
In the hydrogen molecular ion, the kinetic energy lowering of the electron is associated with its delocalization due to electron exchange between the two protons of the molecule. This decrease in the kinetic energy of...In the hydrogen molecular ion, the kinetic energy lowering of the electron is associated with its delocalization due to electron exchange between the two protons of the molecule. This decrease in the kinetic energy of the exchanged electron in the hydrogen molecular ion and the decrease in the dynamical mass of the two exchanged pions in the nucleon-nucleon interaction are at the origin of the attraction mechanism in the molecular covalent bonding and in the nuclear interaction. Based on this unitary approach of the attraction mechanism, the formulas of molecular potential and central nucleon-nucleon potential were derived. The decrease in the mass of the exchanged pions in the nucleon-nucleon bound state, actually means the decrease in the mass of the nucleons. This nucleon mass decrease could be a manifestation of the partial chiral symmetry restoration in nuclear matter.展开更多
Biochar,possessing electron exchange capacities(EEC),is generally involved in environmental redox reactions due to the presence of redox-active moieties(RAMs).The phenomenon that chars containing comparable RAMs posse...Biochar,possessing electron exchange capacities(EEC),is generally involved in environmental redox reactions due to the presence of redox-active moieties(RAMs).The phenomenon that chars containing comparable RAMs possess differential EEC revealed that the accessibility of RAMs is important to the redox properties.However,many studies have focused on the type of RAMs,whereas the distribution has been insufficiently investigated.Herein,we achieved nanoscale observation of electroactive moieties on the surface of six chars using a conductive atomic force microscope.For the two specific kinds of chars with submicron particles and opposite current distributions,the submicron particles took up only 1-4‰wt of biochar accounting for approximately 30-50%of electron-donating capacity(EDC),and electron-accepting capacity(EAC)became 87%and 1.40 times as before after removing submicron particles,respectively.Meanwhile,the combined impact of RAMs and surface topography(that uneven distribution of RAMs resulted in outstanding EEC by enhancing accessibility)was clarified.Furthermore,direct evidence of the link between char structure and EEC(that condensed aromatic structures were indispensable to EAC while both heteroatoms and amorphous aromatics contributed to EDC)was established.These findings can aid in understanding the functions of biochar in biotic and abiotic redox processes.展开更多
文摘The rates of electron exchange between oxidized and reduced forms of sev- eral derivatives of ferrocene(1-3)have been measured in acetonitrile by the NMR line h(?)oadening method at 25℃。It was found that the r(?)tes vary with the lengtn of the substitutent chain and the potential of E_(Fe(Ⅲ)/Fe(Ⅱ))in the ferrocene derivatives.
文摘In the hydrogen molecular ion, the kinetic energy lowering of the electron is associated with its delocalization due to electron exchange between the two protons of the molecule. This decrease in the kinetic energy of the exchanged electron in the hydrogen molecular ion and the decrease in the dynamical mass of the two exchanged pions in the nucleon-nucleon interaction are at the origin of the attraction mechanism in the molecular covalent bonding and in the nuclear interaction. Based on this unitary approach of the attraction mechanism, the formulas of molecular potential and central nucleon-nucleon potential were derived. The decrease in the mass of the exchanged pions in the nucleon-nucleon bound state, actually means the decrease in the mass of the nucleons. This nucleon mass decrease could be a manifestation of the partial chiral symmetry restoration in nuclear matter.
基金the National Key Research&Development Program from Ministry of Science and Technology of China[Grant Number 2018YFD1100600]the Key Research&Development Program from Science Technology Department of Zhejiang Province[2021C03024].
文摘Biochar,possessing electron exchange capacities(EEC),is generally involved in environmental redox reactions due to the presence of redox-active moieties(RAMs).The phenomenon that chars containing comparable RAMs possess differential EEC revealed that the accessibility of RAMs is important to the redox properties.However,many studies have focused on the type of RAMs,whereas the distribution has been insufficiently investigated.Herein,we achieved nanoscale observation of electroactive moieties on the surface of six chars using a conductive atomic force microscope.For the two specific kinds of chars with submicron particles and opposite current distributions,the submicron particles took up only 1-4‰wt of biochar accounting for approximately 30-50%of electron-donating capacity(EDC),and electron-accepting capacity(EAC)became 87%and 1.40 times as before after removing submicron particles,respectively.Meanwhile,the combined impact of RAMs and surface topography(that uneven distribution of RAMs resulted in outstanding EEC by enhancing accessibility)was clarified.Furthermore,direct evidence of the link between char structure and EEC(that condensed aromatic structures were indispensable to EAC while both heteroatoms and amorphous aromatics contributed to EDC)was established.These findings can aid in understanding the functions of biochar in biotic and abiotic redox processes.