Through scanning electron microscope (SEM), spectral analysis, and component analysis tests, the interaction theory between asphalt and rubber was discussed. It is concluded that rubber powder become soft and bond t...Through scanning electron microscope (SEM), spectral analysis, and component analysis tests, the interaction theory between asphalt and rubber was discussed. It is concluded that rubber powder become soft and bond together with each other after being mixed with asphalt. The asphalt changes from a smooth homogeneous matter to a continuous mixing system which is composed of rubber powder and asphalt. The interaction is mainly physical diffusion, but there are some chemical reactions in the process, especially at long reaction time.展开更多
With constant economic development and continuous improvement of living standards in Northeast China,rural tourism,as a new type of tourism,is increasingly favored. From the perspective of symbolic interaction theory,...With constant economic development and continuous improvement of living standards in Northeast China,rural tourism,as a new type of tourism,is increasingly favored. From the perspective of symbolic interaction theory,taking the current situation of rural tourism in Northeast China as an example,this paper explained the semiotic significance between hosts and guests in rural tourism. It established the evaluation indicators for authentic symbolic perception of rural tourism. Also,combined with the theories of sociology and anthropology,it studied the interaction between hosts and tourists of rural tourism in Northeast China.展开更多
Establishing a sense of ritual within tourism consumption scenarios offers tourists the opportunity for interactive engagement.Drawing upon the value co-creation theory,this study constructed an influence mechanism mo...Establishing a sense of ritual within tourism consumption scenarios offers tourists the opportunity for interactive engagement.Drawing upon the value co-creation theory,this study constructed an influence mechanism model to examine tourists'active engagement in the process of co-creating tourism experience values.It employed Partial Least Squares Structural Equation Modeling(PLS-SEM)to empirically test the proposed hypotheses.The findings demonstrate that the model constructed in the present study exhibits robust reliability,validity,and explanatory power.The perception of the sense of ritual in tourism exerts a significant positive influence on tourists’co-creation of tourism experience values,thereby significantly enhancing both the communitas and flow experienced by tourists during their travels.Moreover,such communitas and flow can mediate the influence of the sense of ritual in tourism on tourists’co-creation of tourism experience values.This study contributes to advancing the current research on tourists’co-creation of tourism experience values and the sense of ritual in tourism,thereby providing theoretical foundations for cultivating a sense of ritual within tourism consumption scenarios.展开更多
The mass communication model and interactive ritual chain theory,which serve as communication paradigms in the new media era,facilitate and enhance the synergy between the fields of social history of medicine and heal...The mass communication model and interactive ritual chain theory,which serve as communication paradigms in the new media era,facilitate and enhance the synergy between the fields of social history of medicine and health communication.This study employs a comprehensive framework based on the five elements of the mass communication model:information source,communication subject,communication object,message content,and post-communication feedback.Additionally,it incorporates the interactive ritual chain theory to examine the evolving dynamics and developmental trajectory of research in the social history of medicine during the new media era.Conclusively,this paper acknowledges the existing interaction gaps in the interaction between health communication and the social history of medicine research while outlining the challenges for fostering collaboration and proposing strategic optimizations for effective integration.展开更多
Based on the interactive theory of reading, this study mainly explored the etlects ot topic familiarity and second language proficiency on IVA (Incidental Vocabulary Acquisition) of second language through reading. ...Based on the interactive theory of reading, this study mainly explored the etlects ot topic familiarity and second language proficiency on IVA (Incidental Vocabulary Acquisition) of second language through reading. By using two different measures (translation production and selection), this study found: (1) Vocabulary can be acquired incidentally in reading passages; (2) There are no significant interactive effects of topic familiarity and second language proficiency on vocabulary acquisition, but the two independent variables of topic familiarity and second language proficiency exerted their positively significant effect on incidental vocabulary acquisition, and (3) As for the two vocabulary measures, learners can acquire more words in translation selection than in translation production.展开更多
The paper discusses a field study of different features of the teaching modes of English teacher and Chinese teacher from the perspective of interactive teaching theory.With survey of the translation course reform exp...The paper discusses a field study of different features of the teaching modes of English teacher and Chinese teacher from the perspective of interactive teaching theory.With survey of the translation course reform experimented in Chinese students classroom,the positive exposure of a foreign teacher combined with the work of a Chinese teacher's help in classroom are inspiring for further remolding of a better teaching mode tailored to some special group of Chinese students aiming for study abroad later.The newly teaching mode developed above would serve as a reference for the teaching field.展开更多
Gao's viscous/in-viscid interacting shear flows (ISF) theory, proposed by professor Gao Zhi in Institute of Mechanics, China Academy of Science, and its inferences and their applications in computational fluid dyna...Gao's viscous/in-viscid interacting shear flows (ISF) theory, proposed by professor Gao Zhi in Institute of Mechanics, China Academy of Science, and its inferences and their applications in computational fluid dynamics (CFD) are reviewed and some subjects worthy to be studied are pro- posed in this paper. The flow-field and motion law of ISF, mathematics definition of strong viscous shear layer flow in ISF, ISF equations, wall-surface compatibility criteria (Gao's criteria ), space scale variety law of strong viscous shear layer reveals flow mechanism and local space small scale triggered by strong interaction that cause some abnormal severe local pneumatic heating phenomenon in hypersonic flow. Gao's ISF theory was used in near wall flow, free ISF flow simulation and design of computing grids, Gao's wall-surface criteria were used to verify calculation reliability and accuracy of near wall flows, ISF theory approximate analytical result of shock waves-boundary layer interac- tion and ISF equations were used to obtain the numerical exact solution of local area flow ( such as stationary point flow). Some new subjects, such as, improving near-wall turbulent models according to the turbulent flow simulation satisfying the wall-criteria and illustrating relation between grid-con- vergence based on the wall criteria and other convergence tactics, are suggested. The necessity of applying Gao's ISF theory and wall criteria is revealed. Difficulties and importance of hypersonic vis- cous/in-viscid interaction phenomenon were also emphasized.展开更多
This paper analyses the modal interactions in the nonlinear, size-dependent dynamics of geometrically imperfect microplates. Based on the modified couple stress theory,the equations of motion for the in-plane and out-...This paper analyses the modal interactions in the nonlinear, size-dependent dynamics of geometrically imperfect microplates. Based on the modified couple stress theory,the equations of motion for the in-plane and out-of-plane motions are obtained employing the von Kármán plate theory as well as Kirchhoff's hypotheses by means of the Lagrange equations. The equations of motions are solved using the pseudo-arclength continuation technique and direct timeintegration method. The system parameters are tuned to the values associated with modal interactions, and then nonlinear resonant responses and energy transfer are analysed.Nonlinear motion characteristics are shown in the form of frequency-response and force-response curves, time histories, phase-plane portraits, and fast Fourier transforms.展开更多
Over the last ten years, several comprehensive reviews of iron thermodynamics data were published. This work aims to: (i) propose a consistent set of Gibbs free energies (AfG~) of ferrous hydroxide, Fe(OH)2.cr ...Over the last ten years, several comprehensive reviews of iron thermodynamics data were published. This work aims to: (i) propose a consistent set of Gibbs free energies (AfG~) of ferrous hydroxide, Fe(OH)2.cr and of synthetic Green rusts I and II; (ii) check the consistency of the data of these isostructural compounds by means of a correlation obtained with electronegativities of the anions. Experimental data are concentrations in aqueous solutions and pH, and must be processed to obtain ionic activity products (lAP). The model of Specific Interaction Theory (SIT) was used here. Firstly, some complexes whose existences are doubtful were removed from the SIT database. The new modified database is given here. Secondly, experimental data were processed. Thirdly, the following relation of regression between Gibbs free energies of formation of Green rusts and normalized Allred-Rochow electronegativities of anions was obtained as: △fG0 = -488.354 -353.11 (x/n), r = -0.994. This relation was then used to assess the Gibbs free energy of formation for GR1-OH, simply written as Fe3(OH)7.展开更多
Density functional theory calculations corrected by on-site Coulomb interactions were carried out o study the structures of polar CeO2 (100) surfaces as well as activities during catalytic CO oxidation. The stabilit...Density functional theory calculations corrected by on-site Coulomb interactions were carried out o study the structures of polar CeO2 (100) surfaces as well as activities during catalytic CO oxidation. The stabilities of various CeO2 (100) termination structures are discussed, and calculated energetics are presented. The most stable Ce〇2 (100) surface was obtained by removing half the outermost full layer of oxygen and the surface stability was found to decrease as the exposed oxygen concentration was increased. Assessing the reaction pathways leading to different final products during CO oxidation over the most stable CeO2 (100) surface, we determined that the formation of carbonate species competed with CO2 desorption. However, during CO oxidation on the less stable CeO2 (100) surfaces having more exposed oxygen, the CO is evidently able to react with surface oxygen, leading to CO2 formation and desorption. The calculation results and electronic analyses reported herein also indicate that the characteristic Ce 4/ orbitals are directly involved in deter-mining the surface stabilities and reactivities.展开更多
Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between...Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between quarks in protons in cold hydrogen gas in outskirts of the universe. The mechanisms for such creation of dark matter and PRE are reviewed and updated in greater detail and clearer manner. The so-generated dark matter in a galaxy can account for the galaxy’s rotation curve. Star formation in this galaxy uses up the hydrogen atoms and thereby reduces its dark matter content. Dark matter created in intergalactic hydrogen gas can form filaments. In a hypothetical model of the universe, a hydrogen atom with a small amount of negative relative energy or dark matter at the outskirts of this universe can via collisions with other atoms turn into one with a small positive relative energy PRE. Once such a sign change takes place, gravitational attraction switches to anti-gravity repulsion unopposed by any pressure gradient. This leads to a “run away” hydrogen atom moving away from the mass center of the universe and provides a basic mechanism for the accelerating expansion of the universe. This theoretical expansion and the measured redshift data are both compatible with the conception of an acceleratingly expanding universe and complement each other. But they cannot verify each other directly because the present model has been constructed for purposes different from those of the measurements. But it can be shown that both approaches do support each other qualitatively under certain circumstances for small velocities. Dark matter and PRE in the present model are not foreign objects like WIMPs and dark energy-cosmological constant but can only be created in cold hydrogen gas in gravitational field. To achieve this, infrequent collisions among the hydrogen atoms must take place. Dark matter was created first and can eventually later evolve into PRE in the outskirts of the universe and in the intergalactic void. Dark matter and PRE will disappear if the hydrogen atom carrying them becomes ionized as in stars.展开更多
It is well known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theo...It is well known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theory of gravitational interactions and electromagnetic interactions, a new mechanism of the generation of gravitational field is studied. According to this mechanism, in some special conditions, electromagnetic energy can be directly converted into gravitational energy, and strong gravitational field can be generated without massive stars. Gravity impulse found in experiments is generated by this mechanism.展开更多
The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/...The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/5 that of the deuteron or 1.78 MeV is predicted. This is verified by the dineutron, first observed in 2012, in <sup>16</sup>Be decay. No free dineutrons are expected to exist in nature as they can decay into deuterons. These binding energies are limited by short range strong interaction internucleon forces but consist of long range electrostatic energies from quark charges.展开更多
We apply a recently proposed covariant power counting in nucleon-nucleon interactions to study strangeness S =-1 ΛN-Σ N interactions in chiral effective field theory. At leading order, Lorentz invariance introduces ...We apply a recently proposed covariant power counting in nucleon-nucleon interactions to study strangeness S =-1 ΛN-Σ N interactions in chiral effective field theory. At leading order, Lorentz invariance introduces 12 low energy constants, in contrast to the heavy baryon approach, where only five appear. The Kadyshevsky equation is adopted to resum the potential in order to account for the non-perturbative nature of hyperon-nucleon interactions.A fit to the 36 hyperon-nucleon scattering data points yields χ2 16, which is comparable with the sophisticated phenomenological models and the next-to-leading order heavy baryon approach. However, one cannot achieve a simultaneous description of the nucleon-nucleon phase shifts and strangeness S =-1 hyperon-nucleon scattering data at leading order.展开更多
An upper limit of the average ratio dark matter/ordinary matter in galaxies is estimated to be 8.4, in agreement with the observed ratio 5.4. Upper limit of the average ratio dark energy/ordinary matter for slowly mov...An upper limit of the average ratio dark matter/ordinary matter in galaxies is estimated to be 8.4, in agreement with the observed ratio 5.4. Upper limit of the average ratio dark energy/ordinary matter for slowly moving protons in the outer parts of the universe is estimated to be 8.4, much less than the observed ratio 13.6. The discrepancy is tentatively attributed to that the bulk of the protons in these outer parts of the universe moves fastly and their contribution to dark energy has not been estimated. The positive and negative relative energies between the diquark and quark in the proton play the roles of dark energy and dark matter, respectively.展开更多
Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and s...Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.展开更多
Complexation of two ligands, iminodiacetic acid and ethylenediamine-N,N′-diacetic acid, with molybdenum(Ⅵ) was studied in aqueous solutions. Molybdenum(Ⅵ) forms a mononuclear complex with the aforementioned lig...Complexation of two ligands, iminodiacetic acid and ethylenediamine-N,N′-diacetic acid, with molybdenum(Ⅵ) was studied in aqueous solutions. Molybdenum(Ⅵ) forms a mononuclear complex with the aforementioned ligands of the type MoO3L^2-. All measurements have been carried out at 25 ℃ and different ionic strengths ranging from 0.1 to 1.0 mol·L^-1 of NaClO4, with the pH justified to 6.0. Equilibrium concentration products and stoichiometry of the complexes have been determined from a combination of potentiometric and UV spectroscopic measurements. Comparison of the ionic strength effect on these complex formation reactions has been made using a Debye-Hückel type equation and Bronsted-Guggenheim-Scatchard specific ion interaction theory (SIT). Debye-Hückel theory predicted the first order effects on simple electrolyte solutions. Interactions between the reacting species and the ionic medium were taken into account in the SIT model. All of the calculations have been done by the computer program Excel 2000.展开更多
Motivated by the successes of relativistic theories in studies of atomic/molecular and nuclear systems and the need for a relativistic chiral force in relativistic nuclear structure studies, we explore a new relativis...Motivated by the successes of relativistic theories in studies of atomic/molecular and nuclear systems and the need for a relativistic chiral force in relativistic nuclear structure studies, we explore a new relativistic scheme to construct the nucleon-nucleon interaction in the framework of covariant chiral effective field theory. The chiral interaction is formulated up to leading order with covariant power counting and a Lorentz invariant chiral Lagrangian.We find that the relativistic scheme induces all six spin operators needed to describe the nuclear force. A detailed investigation of the partial wave potentials shows a better description of the;S——0 and;P;phase shifts than the leading order Weinberg approach, and similar to that of the next-to-leading order Weinberg approach. For the other partial waves with angular momenta J≥1, the relativistic results are almost the same as their leading order non-relativistic counterparts.展开更多
‘Behavioural economics’,or the application of methods and evidence from other social sciences to economics,has increased greatly in significance and use in the last two decades.In this paper,we discuss the basic ele...‘Behavioural economics’,or the application of methods and evidence from other social sciences to economics,has increased greatly in significance and use in the last two decades.In this paper,we discuss the basic elements of behavioural economics.We then assess the applications of behavioural economics to the analysis of tax compliance.Our central conclusion is that many,perhaps most,of the recent insights on what motivates tax compliance have flowed directly from behavioural economics.We conclude with suggestions on–and predictions of–directions in which future applications should prove useful.展开更多
基金Funded by Jiangsu Transportation Research Program(No. 05Y07)
文摘Through scanning electron microscope (SEM), spectral analysis, and component analysis tests, the interaction theory between asphalt and rubber was discussed. It is concluded that rubber powder become soft and bond together with each other after being mixed with asphalt. The asphalt changes from a smooth homogeneous matter to a continuous mixing system which is composed of rubber powder and asphalt. The interaction is mainly physical diffusion, but there are some chemical reactions in the process, especially at long reaction time.
基金Supported by Student Innovation Project of University of Science and Technology Liaoning in 2017(201710146000016)
文摘With constant economic development and continuous improvement of living standards in Northeast China,rural tourism,as a new type of tourism,is increasingly favored. From the perspective of symbolic interaction theory,taking the current situation of rural tourism in Northeast China as an example,this paper explained the semiotic significance between hosts and guests in rural tourism. It established the evaluation indicators for authentic symbolic perception of rural tourism. Also,combined with the theories of sociology and anthropology,it studied the interaction between hosts and tourists of rural tourism in Northeast China.
基金This study was supported by the Humanities and Social Sciences Project of the Ministry of Education(No.23YJA790070)the Graduate Innovation Research Project of Southwest Minzu University(No.YB2022621)the Research Project of BCIMY(No.BCIMY1910).
文摘Establishing a sense of ritual within tourism consumption scenarios offers tourists the opportunity for interactive engagement.Drawing upon the value co-creation theory,this study constructed an influence mechanism model to examine tourists'active engagement in the process of co-creating tourism experience values.It employed Partial Least Squares Structural Equation Modeling(PLS-SEM)to empirically test the proposed hypotheses.The findings demonstrate that the model constructed in the present study exhibits robust reliability,validity,and explanatory power.The perception of the sense of ritual in tourism exerts a significant positive influence on tourists’co-creation of tourism experience values,thereby significantly enhancing both the communitas and flow experienced by tourists during their travels.Moreover,such communitas and flow can mediate the influence of the sense of ritual in tourism on tourists’co-creation of tourism experience values.This study contributes to advancing the current research on tourists’co-creation of tourism experience values and the sense of ritual in tourism,thereby providing theoretical foundations for cultivating a sense of ritual within tourism consumption scenarios.
基金University of Science and Technology of China Quality Project History of Medicine(2023YCZX02)Digital Museum Construction Project of Chinese Centre for Disease Control and Prevention(BB2110240080)The National Key R&D project granted by the Ministry of Science and Technology(2018YFA0902400).
文摘The mass communication model and interactive ritual chain theory,which serve as communication paradigms in the new media era,facilitate and enhance the synergy between the fields of social history of medicine and health communication.This study employs a comprehensive framework based on the five elements of the mass communication model:information source,communication subject,communication object,message content,and post-communication feedback.Additionally,it incorporates the interactive ritual chain theory to examine the evolving dynamics and developmental trajectory of research in the social history of medicine during the new media era.Conclusively,this paper acknowledges the existing interaction gaps in the interaction between health communication and the social history of medicine research while outlining the challenges for fostering collaboration and proposing strategic optimizations for effective integration.
文摘Based on the interactive theory of reading, this study mainly explored the etlects ot topic familiarity and second language proficiency on IVA (Incidental Vocabulary Acquisition) of second language through reading. By using two different measures (translation production and selection), this study found: (1) Vocabulary can be acquired incidentally in reading passages; (2) There are no significant interactive effects of topic familiarity and second language proficiency on vocabulary acquisition, but the two independent variables of topic familiarity and second language proficiency exerted their positively significant effect on incidental vocabulary acquisition, and (3) As for the two vocabulary measures, learners can acquire more words in translation selection than in translation production.
文摘The paper discusses a field study of different features of the teaching modes of English teacher and Chinese teacher from the perspective of interactive teaching theory.With survey of the translation course reform experimented in Chinese students classroom,the positive exposure of a foreign teacher combined with the work of a Chinese teacher's help in classroom are inspiring for further remolding of a better teaching mode tailored to some special group of Chinese students aiming for study abroad later.The newly teaching mode developed above would serve as a reference for the teaching field.
基金Supported by the National Natural Science Foundation(10702009)
文摘Gao's viscous/in-viscid interacting shear flows (ISF) theory, proposed by professor Gao Zhi in Institute of Mechanics, China Academy of Science, and its inferences and their applications in computational fluid dynamics (CFD) are reviewed and some subjects worthy to be studied are pro- posed in this paper. The flow-field and motion law of ISF, mathematics definition of strong viscous shear layer flow in ISF, ISF equations, wall-surface compatibility criteria (Gao's criteria ), space scale variety law of strong viscous shear layer reveals flow mechanism and local space small scale triggered by strong interaction that cause some abnormal severe local pneumatic heating phenomenon in hypersonic flow. Gao's ISF theory was used in near wall flow, free ISF flow simulation and design of computing grids, Gao's wall-surface criteria were used to verify calculation reliability and accuracy of near wall flows, ISF theory approximate analytical result of shock waves-boundary layer interac- tion and ISF equations were used to obtain the numerical exact solution of local area flow ( such as stationary point flow). Some new subjects, such as, improving near-wall turbulent models according to the turbulent flow simulation satisfying the wall-criteria and illustrating relation between grid-con- vergence based on the wall criteria and other convergence tactics, are suggested. The necessity of applying Gao's ISF theory and wall criteria is revealed. Difficulties and importance of hypersonic vis- cous/in-viscid interaction phenomenon were also emphasized.
文摘This paper analyses the modal interactions in the nonlinear, size-dependent dynamics of geometrically imperfect microplates. Based on the modified couple stress theory,the equations of motion for the in-plane and out-of-plane motions are obtained employing the von Kármán plate theory as well as Kirchhoff's hypotheses by means of the Lagrange equations. The equations of motions are solved using the pseudo-arclength continuation technique and direct timeintegration method. The system parameters are tuned to the values associated with modal interactions, and then nonlinear resonant responses and energy transfer are analysed.Nonlinear motion characteristics are shown in the form of frequency-response and force-response curves, time histories, phase-plane portraits, and fast Fourier transforms.
文摘Over the last ten years, several comprehensive reviews of iron thermodynamics data were published. This work aims to: (i) propose a consistent set of Gibbs free energies (AfG~) of ferrous hydroxide, Fe(OH)2.cr and of synthetic Green rusts I and II; (ii) check the consistency of the data of these isostructural compounds by means of a correlation obtained with electronegativities of the anions. Experimental data are concentrations in aqueous solutions and pH, and must be processed to obtain ionic activity products (lAP). The model of Specific Interaction Theory (SIT) was used here. Firstly, some complexes whose existences are doubtful were removed from the SIT database. The new modified database is given here. Secondly, experimental data were processed. Thirdly, the following relation of regression between Gibbs free energies of formation of Green rusts and normalized Allred-Rochow electronegativities of anions was obtained as: △fG0 = -488.354 -353.11 (x/n), r = -0.994. This relation was then used to assess the Gibbs free energy of formation for GR1-OH, simply written as Fe3(OH)7.
基金supported the National Natural Science Foundation of China(21421004,21573067)~~
文摘Density functional theory calculations corrected by on-site Coulomb interactions were carried out o study the structures of polar CeO2 (100) surfaces as well as activities during catalytic CO oxidation. The stabilities of various CeO2 (100) termination structures are discussed, and calculated energetics are presented. The most stable Ce〇2 (100) surface was obtained by removing half the outermost full layer of oxygen and the surface stability was found to decrease as the exposed oxygen concentration was increased. Assessing the reaction pathways leading to different final products during CO oxidation over the most stable CeO2 (100) surface, we determined that the formation of carbonate species competed with CO2 desorption. However, during CO oxidation on the less stable CeO2 (100) surfaces having more exposed oxygen, the CO is evidently able to react with surface oxygen, leading to CO2 formation and desorption. The calculation results and electronic analyses reported herein also indicate that the characteristic Ce 4/ orbitals are directly involved in deter-mining the surface stabilities and reactivities.
文摘Dark matter is identified as negative relative energy between quarks in proton and is generated in cold hydrogen gas with pressure gradient in gravitational field. Positive relative energy PRE can be generated between quarks in protons in cold hydrogen gas in outskirts of the universe. The mechanisms for such creation of dark matter and PRE are reviewed and updated in greater detail and clearer manner. The so-generated dark matter in a galaxy can account for the galaxy’s rotation curve. Star formation in this galaxy uses up the hydrogen atoms and thereby reduces its dark matter content. Dark matter created in intergalactic hydrogen gas can form filaments. In a hypothetical model of the universe, a hydrogen atom with a small amount of negative relative energy or dark matter at the outskirts of this universe can via collisions with other atoms turn into one with a small positive relative energy PRE. Once such a sign change takes place, gravitational attraction switches to anti-gravity repulsion unopposed by any pressure gradient. This leads to a “run away” hydrogen atom moving away from the mass center of the universe and provides a basic mechanism for the accelerating expansion of the universe. This theoretical expansion and the measured redshift data are both compatible with the conception of an acceleratingly expanding universe and complement each other. But they cannot verify each other directly because the present model has been constructed for purposes different from those of the measurements. But it can be shown that both approaches do support each other qualitatively under certain circumstances for small velocities. Dark matter and PRE in the present model are not foreign objects like WIMPs and dark energy-cosmological constant but can only be created in cold hydrogen gas in gravitational field. To achieve this, infrequent collisions among the hydrogen atoms must take place. Dark matter was created first and can eventually later evolve into PRE in the outskirts of the universe and in the intergalactic void. Dark matter and PRE will disappear if the hydrogen atom carrying them becomes ionized as in stars.
文摘It is well known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theory of gravitational interactions and electromagnetic interactions, a new mechanism of the generation of gravitational field is studied. According to this mechanism, in some special conditions, electromagnetic energy can be directly converted into gravitational energy, and strong gravitational field can be generated without massive stars. Gravity impulse found in experiments is generated by this mechanism.
文摘The binding energy of the deuteron is estimated from the scalar strong interaction hadron theory SSI. The predicted value is 7.7% lower than the measured value. Existence of a spin 1 dineutron with a binding energy 4/5 that of the deuteron or 1.78 MeV is predicted. This is verified by the dineutron, first observed in 2012, in <sup>16</sup>Be decay. No free dineutrons are expected to exist in nature as they can decay into deuterons. These binding energies are limited by short range strong interaction internucleon forces but consist of long range electrostatic energies from quark charges.
基金Supported by the National Natural Science Foundation of China(11375024,11522539,11375120)the China Postdoctoral Science Foundation(2016M600845,2017T100008)the Fundamental Research Funds for the Central Universities
文摘We apply a recently proposed covariant power counting in nucleon-nucleon interactions to study strangeness S =-1 ΛN-Σ N interactions in chiral effective field theory. At leading order, Lorentz invariance introduces 12 low energy constants, in contrast to the heavy baryon approach, where only five appear. The Kadyshevsky equation is adopted to resum the potential in order to account for the non-perturbative nature of hyperon-nucleon interactions.A fit to the 36 hyperon-nucleon scattering data points yields χ2 16, which is comparable with the sophisticated phenomenological models and the next-to-leading order heavy baryon approach. However, one cannot achieve a simultaneous description of the nucleon-nucleon phase shifts and strangeness S =-1 hyperon-nucleon scattering data at leading order.
文摘An upper limit of the average ratio dark matter/ordinary matter in galaxies is estimated to be 8.4, in agreement with the observed ratio 5.4. Upper limit of the average ratio dark energy/ordinary matter for slowly moving protons in the outer parts of the universe is estimated to be 8.4, much less than the observed ratio 13.6. The discrepancy is tentatively attributed to that the bulk of the protons in these outer parts of the universe moves fastly and their contribution to dark energy has not been estimated. The positive and negative relative energies between the diquark and quark in the proton play the roles of dark energy and dark matter, respectively.
基金the donors of The American Chemical Society Petroleum Research Fund for partial support of this research
文摘Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.
文摘Complexation of two ligands, iminodiacetic acid and ethylenediamine-N,N′-diacetic acid, with molybdenum(Ⅵ) was studied in aqueous solutions. Molybdenum(Ⅵ) forms a mononuclear complex with the aforementioned ligands of the type MoO3L^2-. All measurements have been carried out at 25 ℃ and different ionic strengths ranging from 0.1 to 1.0 mol·L^-1 of NaClO4, with the pH justified to 6.0. Equilibrium concentration products and stoichiometry of the complexes have been determined from a combination of potentiometric and UV spectroscopic measurements. Comparison of the ionic strength effect on these complex formation reactions has been made using a Debye-Hückel type equation and Bronsted-Guggenheim-Scatchard specific ion interaction theory (SIT). Debye-Hückel theory predicted the first order effects on simple electrolyte solutions. Interactions between the reacting species and the ionic medium were taken into account in the SIT model. All of the calculations have been done by the computer program Excel 2000.
基金Supported by National Natural Science Foundation of China(11375024,11522539,11335002,11375120)DFG and NSFC through funds provided to the Sino-German CRC 110“Symmetries and the Emergence of Structure in QCD”(NSFC Grant No.11621131001,DFG Grant No.TRR110)+3 种基金the Major State 973 Program of China(2013CB834400)the China Postdoctoral Science Foundation(2016M600845,2017T100008)the Fundamental Research Funds for the Central Universitiesby the DFG cluster of excellence Origin and Structure of the Universe(www.universe-cluster.de)
文摘Motivated by the successes of relativistic theories in studies of atomic/molecular and nuclear systems and the need for a relativistic chiral force in relativistic nuclear structure studies, we explore a new relativistic scheme to construct the nucleon-nucleon interaction in the framework of covariant chiral effective field theory. The chiral interaction is formulated up to leading order with covariant power counting and a Lorentz invariant chiral Lagrangian.We find that the relativistic scheme induces all six spin operators needed to describe the nuclear force. A detailed investigation of the partial wave potentials shows a better description of the;S——0 and;P;phase shifts than the leading order Weinberg approach, and similar to that of the next-to-leading order Weinberg approach. For the other partial waves with angular momenta J≥1, the relativistic results are almost the same as their leading order non-relativistic counterparts.
文摘‘Behavioural economics’,or the application of methods and evidence from other social sciences to economics,has increased greatly in significance and use in the last two decades.In this paper,we discuss the basic elements of behavioural economics.We then assess the applications of behavioural economics to the analysis of tax compliance.Our central conclusion is that many,perhaps most,of the recent insights on what motivates tax compliance have flowed directly from behavioural economics.We conclude with suggestions on–and predictions of–directions in which future applications should prove useful.