This article studies a class of nonlinear Kirchhoff equations with exponential critical growth,trapping potential,and perturbation.Under appropriate assumptions about f and h,the article obtained the existence of norm...This article studies a class of nonlinear Kirchhoff equations with exponential critical growth,trapping potential,and perturbation.Under appropriate assumptions about f and h,the article obtained the existence of normalized positive solutions for this equation via the Trudinger-Moser inequality and variational methods.Moreover,these solutions are also ground state solutions.Additionally,the article also characterized the asymptotic behavior of solutions.The results of this article expand the research of relevant literature.展开更多
The electronic and superconducting properties of Fe_(1-δ)Se single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T.The results contrast s...The electronic and superconducting properties of Fe_(1-δ)Se single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T.The results contrast sharply with those previously reported for nematically ordered Fe Se by chemical-vapor-transport(CVT)growth.No signature of the electronic nematicity,but an evident metal-to-nonmetal crossover with increasing temperature,is detected in the normal state of the present hydrothermal samples.Interestingly,a higher superconducting critical temperature T_c of 13.2 K is observed compared to a suppressed T_c of 9 K in the presence of the nematicity in the CVT Fe Se.Moreover,the upper critical field in the zero-temperature limit is found to be isotropic with respect to the field direction and to reach a higher value of-42 T,which breaks the Pauli limit by a factor of 1.8.展开更多
In this paper,we study normalized solutions of the Chern-Simons-Schrödinger system with general nonlinearity and a potential in H^(1)(ℝ^(2)).When the nonlinearity satisfies some general 3-superlinear conditions,w...In this paper,we study normalized solutions of the Chern-Simons-Schrödinger system with general nonlinearity and a potential in H^(1)(ℝ^(2)).When the nonlinearity satisfies some general 3-superlinear conditions,we obtain the existence of ground state normalized solutions by using the minimax procedure proposed by Jeanjean in[L.Jeanjean,Existence of solutions with prescribed norm for semilinear elliptic equations,Nonlinear Anal.(1997)].展开更多
In China, economic growing speed converts from high speed to moderate and high speed; economic structure enters from moderate and low end to moderate and high end; development power converts from investment drive to i...In China, economic growing speed converts from high speed to moderate and high speed; economic structure enters from moderate and low end to moderate and high end; development power converts from investment drive to innovation drive, and investment of resource and environ- ment factors presents declining trend. Spatial pattern of economy development is changing greatly, which needs eco-civilization construction and en- vironmental protection field continuously adjusting focus, environmental rules and laws correspondingly regulating, eco-civilization construction and environmental protection field also entering into new normal state. It requires scientifically understanding, actively adapting to and responding to new normal state of eco-civilization construction and environmental protection,and fighting a tough fight. Firstly, we should handle with the relationship between environment and economy, and strive to explore the way of environmental protection. Secondly, we should insist protection priority and prevention oriented,and promote transformation of environmental management strategy. Finally, we should accelerate to promote eco-civilization system reform and environmental protection management system reform, and further promote environmental protection work in Xi＇an on new level from eight aspects.展开更多
In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/...In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/N Under appropriate hypotheses on V(x),we prove that the above Choquard equation has a normalized ground state solution by utilizing variational methods.展开更多
The new normal state of economy is not only the overall trend of China's current economic development stage, but also the strategic choice of China for the future economic development, the anticipation for the eco...The new normal state of economy is not only the overall trend of China's current economic development stage, but also the strategic choice of China for the future economic development, the anticipation for the economic development and its outcome under the new strategy. It is of great strategic significance for the long-term development of China's human rights as a whole, yet it makes a short-term challenge to the realization of the rights of vulnerable groups. Under the new normal state of economy, it should be targeted to strengthen the protection of the rights of vulnerable groups, which is very important not only for the overall development of China's human rights causes, but also for China to cross over 'the middle-income trap' and to achieve sustainable development of economy.展开更多
During epidemic,students in medium-risk or high-risk areas are unable to return to school on time.In response to this new challenge,there is an urgent need to create a new teaching mode to offer on-line courses to tho...During epidemic,students in medium-risk or high-risk areas are unable to return to school on time.In response to this new challenge,there is an urgent need to create a new teaching mode to offer on-line courses to those absent from the offline classes,and we propose a model integrating online and offline teaching.It is based on“dual-camera”method,which allows off-campus students to virtually build up a physical classroom scenario on campus through computers and mobile phones.Using this model,students can participate in class remotely.In order to enhance the engagement of off-campus online students,emphasis is placed on interactive teaching.Teachers are required to design their teaching in advance and to work in collaboration with multiple departments,then using information technology and suitable teaching methods to enable students to participate in physical classroom teaching.This model has been tested in practice and has been successful in meeting the challenges.Finally,4 areas for improvement and refinement are identified.展开更多
The dynamics of quantum discord for two qubits independently interacting with dephasing reservoirs have been studied recently.The authors [Phys.Rev.A 88(2013) 034304] found that for some Bell-diagonal states(BDS)which...The dynamics of quantum discord for two qubits independently interacting with dephasing reservoirs have been studied recently.The authors [Phys.Rev.A 88(2013) 034304] found that for some Bell-diagonal states(BDS)which interact with their environments the calculation of quantum discord could experience a sudden transition in its dynamics,this phenomenon is known as the sudden change.Here in the present paper,we analyze the dynamics of normal quantum discord and super quantum discord for tripartite Bell-diagonal states independently interacting with dephasing reservoirs.Then,we find that basis change does not necessary mean sudden change of quantum correlations.展开更多
When the temperature of certain materials is lowered to exceed a certain value called the critical temperature, a state transition occurs: the system passes from the normal state to the superconducting state. A superc...When the temperature of certain materials is lowered to exceed a certain value called the critical temperature, a state transition occurs: the system passes from the normal state to the superconducting state. A superconductor has two fundamental physical properties: a zero electrical resistance to direct current and a Meissner effect (the material repels any external magnetic flux). Lacking a suitable theory, physicists have attempted to explain the existence of this exotic low-temperature state using phenomenological approaches. In this work, we introduce a semi-classical (non-phenomenological) theory of superconductors. We demonstrate then that only the behavior of the gas of free electrons following the variation of the temperature in the metal explains not only the physical properties of the superconductors but also the existence of superconductors at high critical temperature. The critical temperature then plays the same role as the liquefaction temperature in a gaseous state-liquid state transition and the same role as the Curie temperature in a paramagnetic state-ferromagnetic state transition.展开更多
This paper overviewd the current status of China’s cleaning industry, pointed out the challenges and chances faced by the cleaning industry in the “new normal state”. It also suggested that the cleaning industry sh...This paper overviewd the current status of China’s cleaning industry, pointed out the challenges and chances faced by the cleaning industry in the “new normal state”. It also suggested that the cleaning industry should redefne the industrial target, reconstruct the product line and promote innovation in order to achieve new growth and make breakthroughs.展开更多
The reinforced concrete structure has certain durability. In normal use, with the development of time, the deterioration of materials and the continuous action of loads will cause performance attenuation. Among them, ...The reinforced concrete structure has certain durability. In normal use, with the development of time, the deterioration of materials and the continuous action of loads will cause performance attenuation. Among them, the cracks in reinforced concrete of building structures are the performance of durability limit state. When the crack width exceeds a certain width, it is considered that the structure does not meet the requirements of the normal use limit state, and the structure needs to be identified and strengthened. Therefore, it is very necessary to analyze the causes of cracks in building structures and how to avoid the formation of cracks.展开更多
To overcome the problem of tuning area faults influencing the normal operation of the ZPW-2000A track circuit,protector models are established to protect the track circuit from interference.First,the parameters of the...To overcome the problem of tuning area faults influencing the normal operation of the ZPW-2000A track circuit,protector models are established to protect the track circuit from interference.First,the parameters of the protector models are calculated according to the circuit resonance principle.Second,a four-terminal network model of the track circuit in a normal state is established according to transmission-line theory and the transmission equations are derived.Third,the rail voltage is simulated,and an experimental platform is built to verify the models.Finally,the transmission equations of the protectors are derived,and the variation of the rail voltage is analyzed.The results indicate that tuning area faults have significant influence on the rail voltage.However,the installation of protectors can effectively reduce the influence,and not bear on the normal operation and maintenance of the track circuit,which significantly improves the protection ability of the track circuit against tuning area faults.展开更多
基金Supported by National Natural Science Foundation of China(11671403,11671236)Henan Provincial General Natural Science Foundation Project(232300420113)。
文摘This article studies a class of nonlinear Kirchhoff equations with exponential critical growth,trapping potential,and perturbation.Under appropriate assumptions about f and h,the article obtained the existence of normalized positive solutions for this equation via the Trudinger-Moser inequality and variational methods.Moreover,these solutions are also ground state solutions.Additionally,the article also characterized the asymptotic behavior of solutions.The results of this article expand the research of relevant literature.
基金Supported by the National Key Research and Development Program of China (Grant Nos.2016YFA0300300 and 2017YFA0303003)the National Natural Science Foundation of China (Grant Nos.12061131005,11834016 and 11888101)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDB25000000)the Strategic Priority Research Program and Key Research Program of Frontier Sciences of the Chinese Academy of Sciences (Grant Nos.QYZDY-SSW-SLH001)。
文摘The electronic and superconducting properties of Fe_(1-δ)Se single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T.The results contrast sharply with those previously reported for nematically ordered Fe Se by chemical-vapor-transport(CVT)growth.No signature of the electronic nematicity,but an evident metal-to-nonmetal crossover with increasing temperature,is detected in the normal state of the present hydrothermal samples.Interestingly,a higher superconducting critical temperature T_c of 13.2 K is observed compared to a suppressed T_c of 9 K in the presence of the nematicity in the CVT Fe Se.Moreover,the upper critical field in the zero-temperature limit is found to be isotropic with respect to the field direction and to reach a higher value of-42 T,which breaks the Pauli limit by a factor of 1.8.
基金Supported by the National Natural Science Foundation of China (11971393).
文摘In this paper,we study normalized solutions of the Chern-Simons-Schrödinger system with general nonlinearity and a potential in H^(1)(ℝ^(2)).When the nonlinearity satisfies some general 3-superlinear conditions,we obtain the existence of ground state normalized solutions by using the minimax procedure proposed by Jeanjean in[L.Jeanjean,Existence of solutions with prescribed norm for semilinear elliptic equations,Nonlinear Anal.(1997)].
文摘In China, economic growing speed converts from high speed to moderate and high speed; economic structure enters from moderate and low end to moderate and high end; development power converts from investment drive to innovation drive, and investment of resource and environ- ment factors presents declining trend. Spatial pattern of economy development is changing greatly, which needs eco-civilization construction and en- vironmental protection field continuously adjusting focus, environmental rules and laws correspondingly regulating, eco-civilization construction and environmental protection field also entering into new normal state. It requires scientifically understanding, actively adapting to and responding to new normal state of eco-civilization construction and environmental protection,and fighting a tough fight. Firstly, we should handle with the relationship between environment and economy, and strive to explore the way of environmental protection. Secondly, we should insist protection priority and prevention oriented,and promote transformation of environmental management strategy. Finally, we should accelerate to promote eco-civilization system reform and environmental protection management system reform, and further promote environmental protection work in Xi＇an on new level from eight aspects.
基金Supported by National Natural Science Foundation of China(Grant Nos.11671403 and 11671236)Henan Provincial General Natural Science Foundation Project(Grant No.232300420113)National Natural Science Foundation of China Youth Foud of China Youth Foud(Grant No.12101192).
文摘In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/N Under appropriate hypotheses on V(x),we prove that the above Choquard equation has a normalized ground state solution by utilizing variational methods.
文摘The new normal state of economy is not only the overall trend of China's current economic development stage, but also the strategic choice of China for the future economic development, the anticipation for the economic development and its outcome under the new strategy. It is of great strategic significance for the long-term development of China's human rights as a whole, yet it makes a short-term challenge to the realization of the rights of vulnerable groups. Under the new normal state of economy, it should be targeted to strengthen the protection of the rights of vulnerable groups, which is very important not only for the overall development of China's human rights causes, but also for China to cross over 'the middle-income trap' and to achieve sustainable development of economy.
基金funded by the 2021 Department of Higher Education of the Ministry of Education’s Teaching and Research Projects“Research on the Construction Guidelines,Standards and Norms of Online Open Courses and the Innovation of Teaching and Service Modes”(Grant No.2021)the 2020 Research and Practice Project on the Exploration and Application Promotion of Higher Education’s Teaching Mode Based on MOOC(Grant No.2020)+5 种基金the 2020 Shandong Undergraduate Teaching Reform Research and Cultivation Project“Research and Practice of Hybrid Teaching Mode under the Guidance of the Construction of MOOC Teaching Pilot Colleges”(Grant No.P2020007)2020 Shandong Provincial Undergraduate Teaching Reform Research Key Project“Research and Practice of Top-notch Innovative Talent Training Mode of Interdisciplinary and Professional Integration–Guided by the Construction of Future Technical Colleges”(Grant No.Z2020020)2020 Shandong Provincial Undergraduate Teaching Reform Research and Cultivation Project“Research and Practice of Innovation of New Engineering Agile Education Mode Towards Sustainable Competitiveness”(Grant No.P2020027)2020 Shandong Province Undergraduate Teaching Reform Major Sub Project“Research on the Construction of New Engineering Majors”(Grant No.T202011)2019 Harbin Institute of Technology(Weihai)“Curriculum Ideological and Political”Special Curriculum Construction Project(Grant No.2019)2021 Huawei’s“Smart Base”Project“Course Construction of Computer Composition Principles”(Grant No.IDEA104200302).
文摘During epidemic,students in medium-risk or high-risk areas are unable to return to school on time.In response to this new challenge,there is an urgent need to create a new teaching mode to offer on-line courses to those absent from the offline classes,and we propose a model integrating online and offline teaching.It is based on“dual-camera”method,which allows off-campus students to virtually build up a physical classroom scenario on campus through computers and mobile phones.Using this model,students can participate in class remotely.In order to enhance the engagement of off-campus online students,emphasis is placed on interactive teaching.Teachers are required to design their teaching in advance and to work in collaboration with multiple departments,then using information technology and suitable teaching methods to enable students to participate in physical classroom teaching.This model has been tested in practice and has been successful in meeting the challenges.Finally,4 areas for improvement and refinement are identified.
文摘The dynamics of quantum discord for two qubits independently interacting with dephasing reservoirs have been studied recently.The authors [Phys.Rev.A 88(2013) 034304] found that for some Bell-diagonal states(BDS)which interact with their environments the calculation of quantum discord could experience a sudden transition in its dynamics,this phenomenon is known as the sudden change.Here in the present paper,we analyze the dynamics of normal quantum discord and super quantum discord for tripartite Bell-diagonal states independently interacting with dephasing reservoirs.Then,we find that basis change does not necessary mean sudden change of quantum correlations.
文摘When the temperature of certain materials is lowered to exceed a certain value called the critical temperature, a state transition occurs: the system passes from the normal state to the superconducting state. A superconductor has two fundamental physical properties: a zero electrical resistance to direct current and a Meissner effect (the material repels any external magnetic flux). Lacking a suitable theory, physicists have attempted to explain the existence of this exotic low-temperature state using phenomenological approaches. In this work, we introduce a semi-classical (non-phenomenological) theory of superconductors. We demonstrate then that only the behavior of the gas of free electrons following the variation of the temperature in the metal explains not only the physical properties of the superconductors but also the existence of superconductors at high critical temperature. The critical temperature then plays the same role as the liquefaction temperature in a gaseous state-liquid state transition and the same role as the Curie temperature in a paramagnetic state-ferromagnetic state transition.
文摘This paper overviewd the current status of China’s cleaning industry, pointed out the challenges and chances faced by the cleaning industry in the “new normal state”. It also suggested that the cleaning industry should redefne the industrial target, reconstruct the product line and promote innovation in order to achieve new growth and make breakthroughs.
文摘The reinforced concrete structure has certain durability. In normal use, with the development of time, the deterioration of materials and the continuous action of loads will cause performance attenuation. Among them, the cracks in reinforced concrete of building structures are the performance of durability limit state. When the crack width exceeds a certain width, it is considered that the structure does not meet the requirements of the normal use limit state, and the structure needs to be identified and strengthened. Therefore, it is very necessary to analyze the causes of cracks in building structures and how to avoid the formation of cracks.
基金Supported by the National Natural Science Foundation of China(61763023).
文摘To overcome the problem of tuning area faults influencing the normal operation of the ZPW-2000A track circuit,protector models are established to protect the track circuit from interference.First,the parameters of the protector models are calculated according to the circuit resonance principle.Second,a four-terminal network model of the track circuit in a normal state is established according to transmission-line theory and the transmission equations are derived.Third,the rail voltage is simulated,and an experimental platform is built to verify the models.Finally,the transmission equations of the protectors are derived,and the variation of the rail voltage is analyzed.The results indicate that tuning area faults have significant influence on the rail voltage.However,the installation of protectors can effectively reduce the influence,and not bear on the normal operation and maintenance of the track circuit,which significantly improves the protection ability of the track circuit against tuning area faults.
