In this paper,the Lie symmetry analysis method is applied to the(2+1)-dimensional time-fractional Heisenberg ferromagnetic spin chain equation.We obtain all the Lie symmetries admitted by the governing equation and re...In this paper,the Lie symmetry analysis method is applied to the(2+1)-dimensional time-fractional Heisenberg ferromagnetic spin chain equation.We obtain all the Lie symmetries admitted by the governing equation and reduce the corresponding(2+1)-dimensional fractional partial differential equations with the Riemann–Liouville fractional derivative to(1+1)-dimensional counterparts with the Erdélyi–Kober fractional derivative.Then,we obtain the power series solutions of the reduced equations,prove their convergence and analyze their dynamic behavior graphically.In addition,the conservation laws for all the obtained Lie symmetries are constructed using the new conservation theorem and the generalization of Noether operators.展开更多
Silicate perovskites（（Mg, Fe）SiO 3 and CaS iO 3） are believed to be the major constituent minerals in the lower mantle. The phase relation, solid solution, spin state of iron and water solubility related to the lo...Silicate perovskites（（Mg, Fe）SiO 3 and CaS iO 3） are believed to be the major constituent minerals in the lower mantle. The phase relation, solid solution, spin state of iron and water solubility related to the lower mantle perovskite are of great effect on the geodynamics of the Earth＇s interior and on ore mineralization. Previous studies indicate that a large amount of iron coupled with aluminum can incorporate into magnesium perovskite, but this is discordant with the disproportionation of（Mg,Fe）SiO 3 perovskite into iron-free MgS i O3 perovskite and hexagonal phase（Mg0.6Fe0.4）SiO 3 in the Earth＇s lower mantle. MnS iO 3 is the first chemical component confirmed to form wide range solid solution with Ca SiO 3 perovskite and complete solid solution with MgS i O3 perovskite at the P-T conditions in the lower mantle, and addition of Mn Si O3 will strongly affects the mutual solubility between Mg Si O3 and CaS iO 3. The spin state of iron is deeply depends on the site occupation of the Fe3＋or Fe2＋, the synthesis and the annealing conditions of the sample. It seems that the spin state of Fe2＋ in the lower mantle perovskite can be settled as high spin, however, the existence of intermediate spin or low spin state of Fe2＋ in perovskite has not been clarified. Moreover, different results have also been reported for the spin state of Fe3＋ in perovskite. The water solubility of the lower mantle perovskite is related with its composition. In pure Mg SiO 3 perovskite, only less than 500 ppm water was reported. Al–Mg Si O3 perovskite or Al–Fe–MgS iO 3 perovskite in the lower mantle accommodates water of 1100 to 1800 ppm. Further experiments are necessary to clarify the detailed conditions for perovskite solid solution, to reliably analyze the valence and spin states of iron in the coexisting iron-bearing phases, and to compare the water solubility of different phases at different layers for deeply understanding the geodynamics of the Earth＇s interior and ore mineralization.展开更多
Jingwei Intelligent Textile Machinery Co.,Ltd.is a globally leading enterprise in the R&D and manufacturing of textile machinery,affiliated with China National Machinery Industry Group(SINOMACH).As the first moder...Jingwei Intelligent Textile Machinery Co.,Ltd.is a globally leading enterprise in the R&D and manufacturing of textile machinery,affiliated with China National Machinery Industry Group(SINOMACH).As the first modern textile machinery manufacturing base in New China,the company has developed over 70 years to establish a full lifecycle service capability of"machines+components+services+modifications."Its core products,such as Ring Spinning Frames and Combers,feature internationally advanced technologies.With products exported to over 40 countries and regions,the company is committed to providing global customers with intelligent,green textile equipment and full-process solutions.展开更多
An exact solution of a single impurity model is hard to derive since it breaks translation invariance symmetry. We present the exact solution of the spin-1/2 transverse Ising chain imbedded by a spin-1 impurity. Using...An exact solution of a single impurity model is hard to derive since it breaks translation invariance symmetry. We present the exact solution of the spin-1/2 transverse Ising chain imbedded by a spin-1 impurity. Using the hole decompo- sition scheme, we exactly solve the spin-1 impurity in two subspaces which are generated by a conserved hole operator. The impurity enlarges the energy deformation of the ground state above a pure transverse Ising system without impurity. The specific heat coefficient shows a small anomaly at low temperature for finite size. This indicates that the impurity can tune the ground state from a magnetic impurity space to a non-magnetic impurity space, which only exists for spin-1 impurity comparing with spin-1/2 impurity and a pure transverse Ising chain without impurity. These behaviors essentially come from adding impurity freedom, which induces a competition between hole and fermion excitation depending on the coupling strength with its neighbor and the single-ion anisotropy.展开更多
We investigate spin squeezing effects of trapped ions in an off-resonance optical potential system using the arbitrary range spin spin interaction and transverse field model. The collective spin noises at any time are...We investigate spin squeezing effects of trapped ions in an off-resonance optical potential system using the arbitrary range spin spin interaction and transverse field model. The collective spin noises at any time are analyzed exactly. The general expression of spin squeezing factor is presented for arbitrary-range spin interaction. For the nearest-neighbor and next-nearest neighbor spin interaction model, the analytic solutions are reduced from the general expressions. It is shown that the maximum spin squeezing is enhanced for the general arbitrary-range spin interaction compared with the nearest-neighbor interaction model as the long-range interaction with arbitrary sites enforces stronger correlation.展开更多
The random K-satisfiability （K-SAT） problem is very diffcult when the clause density is close to the satisfiability threshold. In this paper we study this problem from the perspective of solution space coupling. We ...The random K-satisfiability （K-SAT） problem is very diffcult when the clause density is close to the satisfiability threshold. In this paper we study this problem from the perspective of solution space coupling. We divide a given difficult random K-SAT formula into two easy sub-formulas and let the two corresponding solution spaces to interact with each other through a coupling field x. We investigate the statistical mechanical property of this coupled system by mean field theory and computer simulations. The coupled system has an ergodicity-breaking （clustering） transition at certain critical value Xd of the coupling field. At this transition point, the mean overlap value between the solutions of the two solution spaces is very close to 1. The mean energy density of the coupled system at its clustering transition point is less than the mean energy density of the original K-SAT problem at the temperature-induced clustering transition point. The implications of this work for designing new heuristic K-SAT solvers are discussed.展开更多
Recently, the bound state solutions of a confined Klein-Gordon particle under the mixed scalar-vector generalized symmetric Woods-Saxon potential in one spatial dimension have been investigated. The obtained results r...Recently, the bound state solutions of a confined Klein-Gordon particle under the mixed scalar-vector generalized symmetric Woods-Saxon potential in one spatial dimension have been investigated. The obtained results reveal that in the spin symmetric limit discrete spectrum exists, while in the pseudo-spin symmetric limit it does not.In this manuscript, new insights and information are given by employing an analogy of the variational principle. The role of the difference of the magnitudes of the vector and scalar potential energies, namely the differentiation parameter,on the energy spectrum is examined. It is observed that the differentiation parameter determines the measure of the energy spectrum density by modifying the confined particle's mass-energy in addition to narrowing the spectrum interval length.展开更多
A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is proposed.The displacement and bending angle functions are represented through an improved Fourier seri...A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is proposed.The displacement and bending angle functions are represented through an improved Fourier series,which ensures the continuity of the derivative at the boundary and enhances the convergence.The exact characteristic equations of the multi-span spinning beams with elastic constraints under an axial compressive force are derived by the Lagrange equation.The efficiency and accuracy of the present method are validated in comparison with the finite element method(FEM)and other methods.The effects of the boundary spring stiffness,the number of spans,the spinning velocity,and the axial compressive force on the dynamic characteristics of the multi-span spinning beams are studied.The results show that the present method can freely simulate any boundary constraints without modifying the solution process.The elastic range of linear springs is larger than that of torsion springs,and it is not affected by the number of spans.With an increase in the axial compressive force,the attenuation rate of the natural frequency of a spinning beam with a large number of spans becomes larger,while the attenuation rate with an elastic boundary is lower than that under a classic simply supported boundary.展开更多
Solution blow spinning(SBS)applies high-speed airflow to prepare fibers by generating a strong stretching force.It has the advantages of scalable production,tailorable morphologies,and wide applicability.Yet,the SBS s...Solution blow spinning(SBS)applies high-speed airflow to prepare fibers by generating a strong stretching force.It has the advantages of scalable production,tailorable morphologies,and wide applicability.Yet,the SBS strategy can hardly prepare fibers down to the sub-100 nanometers,which limits its performance in demanding applications.Herein,we overcome the limitation of SBS by introducing a second airflow.This novel strategy is termed double-stretching SBS(DS-SBS)because an extra stretching force is exerted on the fiber when it converges with the second airflow.Polyamide6 nanofibers with an average diameter of 80 nm are successfully prepared with the DS-SBS strategy,while the SBS strategy could only prepare submicron fibers with an average diameter of 120 nm.Further,the generality of the DS-SBS strategy to reduce fiber diameter is verified on numerous solute-solvent pairs.展开更多
Exact analytical solutions are good candidates for studying and explaining the dynamics of solitons in nonlinear systems.We further extend the region of existence of spin solitons in the nonlinearity coefficient space...Exact analytical solutions are good candidates for studying and explaining the dynamics of solitons in nonlinear systems.We further extend the region of existence of spin solitons in the nonlinearity coefficient space for the spin-1 Bose-Einstein condensate.Six types of spin soliton solutions can be obtained,and they exist in different regions.Stability analysis and numerical simulation results indicate that three types of spin solitons are stable against weak noise.The non-integrable properties of the model can induce shape oscillation and increase in speed after the collision between two spin solitons.These results further enrich the soliton family for non-integrable models and can provide theoretical references for experimental studies.展开更多
Study on the application of nanofibers in food active packaging has been a research hotspot in recent years.In this work,solution blow spinning(SBS)was applied to rapidly fabricate the polycaprolactone(PCL),polyvinyl ...Study on the application of nanofibers in food active packaging has been a research hotspot in recent years.In this work,solution blow spinning(SBS)was applied to rapidly fabricate the polycaprolactone(PCL),polyvinyl pyrrolidone(PVP),and PCL/PVP nanofibrous films to encapsulate chlorogenic acid(CGA).All films showed uniform and smooth nanofibers,and the Fourier transform infrared spectroscopy and X-ray diffraction proved the success of mixed spinning of PCL and PVP.With the increase of PVP content,the thermal stability of the PCL/PVP nanofibrous films improved.The PCL/PVP(weight ratio of 4:1)film possessed better mechanical properties than PCL and PVP films be-cause of the stronger fiber-fiber interactions.The addition of PCL endowed the hydrophobic surfaces to the PCL/PVP films,and the PCL/PVP films had better water vapor barrier ability.The PCL/PVP(4:1)film exhibited the best long-term continuous release of CGA during 72 h.The PVP nanofibrous film exhibited no inhibition against Staphylococcus aureus and Escherichia coli due to the low encapsulation efficiency,but the PCL and PCL/PVP films exhibited good antimicrobial activity.The above results suggested that the nanofibrous fims developed by SBS possess promising prospects in food packaging.展开更多
In this paper,the global existence and uniqueness of a smooth solution to the periodic initial-value problem of the spin equations of antiferromagnets in 1 dimension are proved.
基金supported by the State Key Program of the National Natural Science Foundation of China(72031009).
文摘In this paper,the Lie symmetry analysis method is applied to the(2+1)-dimensional time-fractional Heisenberg ferromagnetic spin chain equation.We obtain all the Lie symmetries admitted by the governing equation and reduce the corresponding(2+1)-dimensional fractional partial differential equations with the Riemann–Liouville fractional derivative to(1+1)-dimensional counterparts with the Erdélyi–Kober fractional derivative.Then,we obtain the power series solutions of the reduced equations,prove their convergence and analyze their dynamic behavior graphically.In addition,the conservation laws for all the obtained Lie symmetries are constructed using the new conservation theorem and the generalization of Noether operators.
基金partly supported by projects from JSPS KAKENHI (Grant No. 18340167)MEXT KAKENHI (Grant No. 20103002)+2 种基金NSFC (Grand No.90914002)China Geological Survey (Grant No. 1212011220926)the Ministry of Education of China (Grant No. 20130022110003)
文摘Silicate perovskites（（Mg, Fe）SiO 3 and CaS iO 3） are believed to be the major constituent minerals in the lower mantle. The phase relation, solid solution, spin state of iron and water solubility related to the lower mantle perovskite are of great effect on the geodynamics of the Earth＇s interior and on ore mineralization. Previous studies indicate that a large amount of iron coupled with aluminum can incorporate into magnesium perovskite, but this is discordant with the disproportionation of（Mg,Fe）SiO 3 perovskite into iron-free MgS i O3 perovskite and hexagonal phase（Mg0.6Fe0.4）SiO 3 in the Earth＇s lower mantle. MnS iO 3 is the first chemical component confirmed to form wide range solid solution with Ca SiO 3 perovskite and complete solid solution with MgS i O3 perovskite at the P-T conditions in the lower mantle, and addition of Mn Si O3 will strongly affects the mutual solubility between Mg Si O3 and CaS iO 3. The spin state of iron is deeply depends on the site occupation of the Fe3＋or Fe2＋, the synthesis and the annealing conditions of the sample. It seems that the spin state of Fe2＋ in the lower mantle perovskite can be settled as high spin, however, the existence of intermediate spin or low spin state of Fe2＋ in perovskite has not been clarified. Moreover, different results have also been reported for the spin state of Fe3＋ in perovskite. The water solubility of the lower mantle perovskite is related with its composition. In pure Mg SiO 3 perovskite, only less than 500 ppm water was reported. Al–Mg Si O3 perovskite or Al–Fe–MgS iO 3 perovskite in the lower mantle accommodates water of 1100 to 1800 ppm. Further experiments are necessary to clarify the detailed conditions for perovskite solid solution, to reliably analyze the valence and spin states of iron in the coexisting iron-bearing phases, and to compare the water solubility of different phases at different layers for deeply understanding the geodynamics of the Earth＇s interior and ore mineralization.
文摘Jingwei Intelligent Textile Machinery Co.,Ltd.is a globally leading enterprise in the R&D and manufacturing of textile machinery,affiliated with China National Machinery Industry Group(SINOMACH).As the first modern textile machinery manufacturing base in New China,the company has developed over 70 years to establish a full lifecycle service capability of"machines+components+services+modifications."Its core products,such as Ring Spinning Frames and Combers,feature internationally advanced technologies.With products exported to over 40 countries and regions,the company is committed to providing global customers with intelligent,green textile equipment and full-process solutions.
基金Project supported by the Xinjiang Natural Science Foundation of China(Grant No.2016D01C003)
文摘An exact solution of a single impurity model is hard to derive since it breaks translation invariance symmetry. We present the exact solution of the spin-1/2 transverse Ising chain imbedded by a spin-1 impurity. Using the hole decompo- sition scheme, we exactly solve the spin-1 impurity in two subspaces which are generated by a conserved hole operator. The impurity enlarges the energy deformation of the ground state above a pure transverse Ising system without impurity. The specific heat coefficient shows a small anomaly at low temperature for finite size. This indicates that the impurity can tune the ground state from a magnetic impurity space to a non-magnetic impurity space, which only exists for spin-1 impurity comparing with spin-1/2 impurity and a pure transverse Ising chain without impurity. These behaviors essentially come from adding impurity freedom, which induces a competition between hole and fermion excitation depending on the coupling strength with its neighbor and the single-ion anisotropy.
基金Supported by the National Natural Science Foundation of China under Grant No 51427801
文摘We investigate spin squeezing effects of trapped ions in an off-resonance optical potential system using the arbitrary range spin spin interaction and transverse field model. The collective spin noises at any time are analyzed exactly. The general expression of spin squeezing factor is presented for arbitrary-range spin interaction. For the nearest-neighbor and next-nearest neighbor spin interaction model, the analytic solutions are reduced from the general expressions. It is shown that the maximum spin squeezing is enhanced for the general arbitrary-range spin interaction compared with the nearest-neighbor interaction model as the long-range interaction with arbitrary sites enforces stronger correlation.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences under Grant No.KJCX2-EW-J02the Natural National Science Foundation of China under Grant Nos.11121403 and 11225526
文摘The random K-satisfiability （K-SAT） problem is very diffcult when the clause density is close to the satisfiability threshold. In this paper we study this problem from the perspective of solution space coupling. We divide a given difficult random K-SAT formula into two easy sub-formulas and let the two corresponding solution spaces to interact with each other through a coupling field x. We investigate the statistical mechanical property of this coupled system by mean field theory and computer simulations. The coupled system has an ergodicity-breaking （clustering） transition at certain critical value Xd of the coupling field. At this transition point, the mean overlap value between the solutions of the two solution spaces is very close to 1. The mean energy density of the coupled system at its clustering transition point is less than the mean energy density of the original K-SAT problem at the temperature-induced clustering transition point. The implications of this work for designing new heuristic K-SAT solvers are discussed.
基金Supported by the Turkish Science and Research Council(TüB.ITAK)Akdeniz Universitythe support given by the Internal Project of Excellent Research of the Faculty of Science of University Hradec Králové,"Studying of properties of confined quantum particle using Woods-Saxon potential"
文摘Recently, the bound state solutions of a confined Klein-Gordon particle under the mixed scalar-vector generalized symmetric Woods-Saxon potential in one spatial dimension have been investigated. The obtained results reveal that in the spin symmetric limit discrete spectrum exists, while in the pseudo-spin symmetric limit it does not.In this manuscript, new insights and information are given by employing an analogy of the variational principle. The role of the difference of the magnitudes of the vector and scalar potential energies, namely the differentiation parameter,on the energy spectrum is examined. It is observed that the differentiation parameter determines the measure of the energy spectrum density by modifying the confined particle's mass-energy in addition to narrowing the spectrum interval length.
基金Project supported by the National Science Fund for Distinguished Young Scholars of China (No.11925205)the National Natural Science Foundation of China (Nos.51921003 and 12272165)。
文摘A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is proposed.The displacement and bending angle functions are represented through an improved Fourier series,which ensures the continuity of the derivative at the boundary and enhances the convergence.The exact characteristic equations of the multi-span spinning beams with elastic constraints under an axial compressive force are derived by the Lagrange equation.The efficiency and accuracy of the present method are validated in comparison with the finite element method(FEM)and other methods.The effects of the boundary spring stiffness,the number of spans,the spinning velocity,and the axial compressive force on the dynamic characteristics of the multi-span spinning beams are studied.The results show that the present method can freely simulate any boundary constraints without modifying the solution process.The elastic range of linear springs is larger than that of torsion springs,and it is not affected by the number of spans.With an increase in the axial compressive force,the attenuation rate of the natural frequency of a spinning beam with a large number of spans becomes larger,while the attenuation rate with an elastic boundary is lower than that under a classic simply supported boundary.
基金supported by the Basic Science Center Program of the National Natural Science Foundation of China(NSFC)(No.51788104)Beijing Natural Science Foundation(No.JQ19005).
文摘Solution blow spinning(SBS)applies high-speed airflow to prepare fibers by generating a strong stretching force.It has the advantages of scalable production,tailorable morphologies,and wide applicability.Yet,the SBS strategy can hardly prepare fibers down to the sub-100 nanometers,which limits its performance in demanding applications.Herein,we overcome the limitation of SBS by introducing a second airflow.This novel strategy is termed double-stretching SBS(DS-SBS)because an extra stretching force is exerted on the fiber when it converges with the second airflow.Polyamide6 nanofibers with an average diameter of 80 nm are successfully prepared with the DS-SBS strategy,while the SBS strategy could only prepare submicron fibers with an average diameter of 120 nm.Further,the generality of the DS-SBS strategy to reduce fiber diameter is verified on numerous solute-solvent pairs.
基金supported by the National Natural Science Foundation of China(Contract Nos.12375005 and 12235007)the Major Basic Research Program of Natural Science of Shaanxi Province(Grant No.2018KJXX-094).
文摘Exact analytical solutions are good candidates for studying and explaining the dynamics of solitons in nonlinear systems.We further extend the region of existence of spin solitons in the nonlinearity coefficient space for the spin-1 Bose-Einstein condensate.Six types of spin soliton solutions can be obtained,and they exist in different regions.Stability analysis and numerical simulation results indicate that three types of spin solitons are stable against weak noise.The non-integrable properties of the model can induce shape oscillation and increase in speed after the collision between two spin solitons.These results further enrich the soliton family for non-integrable models and can provide theoretical references for experimental studies.
基金the Fundamental.Research Funds for the Central Universities(K20210202),Chinathe Zhejiang Provincial San Nong Jiu Fang’Science and Technology Collaboration Program of China(2022SNJF020).
文摘Study on the application of nanofibers in food active packaging has been a research hotspot in recent years.In this work,solution blow spinning(SBS)was applied to rapidly fabricate the polycaprolactone(PCL),polyvinyl pyrrolidone(PVP),and PCL/PVP nanofibrous films to encapsulate chlorogenic acid(CGA).All films showed uniform and smooth nanofibers,and the Fourier transform infrared spectroscopy and X-ray diffraction proved the success of mixed spinning of PCL and PVP.With the increase of PVP content,the thermal stability of the PCL/PVP nanofibrous films improved.The PCL/PVP(weight ratio of 4:1)film possessed better mechanical properties than PCL and PVP films be-cause of the stronger fiber-fiber interactions.The addition of PCL endowed the hydrophobic surfaces to the PCL/PVP films,and the PCL/PVP films had better water vapor barrier ability.The PCL/PVP(4:1)film exhibited the best long-term continuous release of CGA during 72 h.The PVP nanofibrous film exhibited no inhibition against Staphylococcus aureus and Escherichia coli due to the low encapsulation efficiency,but the PCL and PCL/PVP films exhibited good antimicrobial activity.The above results suggested that the nanofibrous fims developed by SBS possess promising prospects in food packaging.
基金supported by the Natural Science Foundation of China(No.19971030)the Natural Science Foundation of Guangdong(No.000671,No.031495)
文摘In this paper,the global existence and uniqueness of a smooth solution to the periodic initial-value problem of the spin equations of antiferromagnets in 1 dimension are proved.
