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
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
The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>...The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub>,Bi<sub>1.8</sub>Sb<sub>0.2</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub> and Bi<sub>1.7</sub>Pb<sub>0.2</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>2</sub>O<sub>x</sub>. The charge transfer from Cu-Olayers to Bi-O layers has been observed across T<sub>c</sub>s for all samples.Three samples allshow two normal state anomalies around 160 K and 240 K,respectively.The anomalyaround 160 K is attributed to the structural instability and that around 240 Kpresumably to the displacement phase transition.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
2008年金融危机后,全球经济基本步入“新常态”.为应对“新常态”,中国政府采取措施,使全国经济呈现新“外貌”.针对新常态背景下房地产和股市状况,以国房景气指数代表中国房地产行业发展情况、上证综合指数收盘价表示股市行情,建立Y A...2008年金融危机后,全球经济基本步入“新常态”.为应对“新常态”,中国政府采取措施,使全国经济呈现新“外貌”.针对新常态背景下房地产和股市状况,以国房景气指数代表中国房地产行业发展情况、上证综合指数收盘价表示股市行情,建立Y A R 模型进行分析.之后引入货币供给量,重新建立模型,经脉冲响应、方差分解分析,得出上证综指、国房景气指数主要受自身行业的影响;货币供给量给房市和股市造成的影响度大于两个市场相互间的影响程度;观察短期内房地产行业、股市两者之间相互的贡献度,房市对股市的贡献度更大.展开更多
In unconventional superconductors, it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism. In conventional supercon...In unconventional superconductors, it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism. In conventional superconductors like niobium or lead, the normal state is a Fermi liquid with a well-defined Fermi surface and well-defined quasipartcles along the Fermi surface. Superconductivity is realized in this case by the Fermi surface instability in the superconducting state and the formation and condensation of the electron pairs(Cooper pairing). The high temperature cuprate superconductors, on the other hand, represent another extreme case that superconductivity can be realized in the underdoped region where there is neither well-defined Fermi surface due to the pseudogap formation nor quasiparticles near the antinodal regions in the normal state. Here we report a novel scenario that superconductivity is realized in a system with well-defined Fermi surface but without quasiparticles along the Fermi surface in the normal state.High resolution laser-based angle-resolved photoemission measurements have been performed on an optimally-doped iron-based superconductor(Ba_(0.6)K_(0.4))Fe_2As_2. We find that, while sharp superconducting coherence peaks emerge in the superconducting state on the hole-like Fermi surface sheets, no quasiparticle peak is present in the normal state. Its electronic behaviours deviate strongly from a Fermi liquid system. The superconducting gap of such a system exhibits an unusual temperature dependence that it is nearly a constant in the superconducting state and abruptly closes at Tc. These observations have provided a new platform to study unconventional superconductivity in a non-Fermi liquid system.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
For the first time,we derive the compact forms of normalization factors for photon-added（-subtracted） two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of o...For the first time,we derive the compact forms of normalization factors for photon-added（-subtracted） two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators（IWOP） technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented.展开更多
Optomechanical dynamics in two systems which are a transmission line resonator and Fabrya-Perot optical cavity via radiation-pressure are investigated by linearized quantum Langevin equation. We work in the resolved s...Optomechanical dynamics in two systems which are a transmission line resonator and Fabrya-Perot optical cavity via radiation-pressure are investigated by linearized quantum Langevin equation. We work in the resolved sideband regime where the oscillator resonance frequency exceeds the cavity linewidth. Normal mode splittings of the mechanical resonator as a pure result of the coupling interaction in the two optomechanical systems is studied, and we make a comparison of normal mode splitting of mechanical resonator between the two systems. In the optical cavity, the normal mode splitting of the movable mirror approaches the latest experiment very well. In addition, an approximation scheme is introduced to demonstrate the ground state cooling, and we make a comparison of cooling between the two systems dominated by two key factors, which are the initial bath temperature and the mechanical quality factor. Since both the normal mode splitting and cooling require working in the resolved sideband regime, whether the normal mode splitting influences the cooling of the mirror is considered. Considering the size of the mechanical resonator and precooling the system, the mechanical resonator in the transmission line resonator system is easier to achieve the ground state cooling than in optical cavity.展开更多
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.
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The project supported by IAEA under the Contract No.5295/RBby China National Nuclear Corporation.
文摘The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub>,Bi<sub>1.8</sub>Sb<sub>0.2</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub> and Bi<sub>1.7</sub>Pb<sub>0.2</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>2</sub>O<sub>x</sub>. The charge transfer from Cu-Olayers to Bi-O layers has been observed across T<sub>c</sub>s for all samples.Three samples allshow two normal state anomalies around 160 K and 240 K,respectively.The anomalyaround 160 K is attributed to the structural instability and that around 240 Kpresumably to the displacement phase transition.
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2008年金融危机后,全球经济基本步入“新常态”.为应对“新常态”,中国政府采取措施,使全国经济呈现新“外貌”.针对新常态背景下房地产和股市状况,以国房景气指数代表中国房地产行业发展情况、上证综合指数收盘价表示股市行情,建立Y A R 模型进行分析.之后引入货币供给量,重新建立模型,经脉冲响应、方差分解分析,得出上证综指、国房景气指数主要受自身行业的影响;货币供给量给房市和股市造成的影响度大于两个市场相互间的影响程度;观察短期内房地产行业、股市两者之间相互的贡献度,房市对股市的贡献度更大.
基金supported by the National Key Research and Development Program of China (2016YFA0300300 and 2017YFA0302900)the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (XDB07020300 and XDB25000000)+1 种基金the National Basic Research Program of China (2015CB921000), the National Natural Science Foundation of China (11334010)and the Youth Innovation Promotion Association of CAS (2017013)
文摘In unconventional superconductors, it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism. In conventional superconductors like niobium or lead, the normal state is a Fermi liquid with a well-defined Fermi surface and well-defined quasipartcles along the Fermi surface. Superconductivity is realized in this case by the Fermi surface instability in the superconducting state and the formation and condensation of the electron pairs(Cooper pairing). The high temperature cuprate superconductors, on the other hand, represent another extreme case that superconductivity can be realized in the underdoped region where there is neither well-defined Fermi surface due to the pseudogap formation nor quasiparticles near the antinodal regions in the normal state. Here we report a novel scenario that superconductivity is realized in a system with well-defined Fermi surface but without quasiparticles along the Fermi surface in the normal state.High resolution laser-based angle-resolved photoemission measurements have been performed on an optimally-doped iron-based superconductor(Ba_(0.6)K_(0.4))Fe_2As_2. We find that, while sharp superconducting coherence peaks emerge in the superconducting state on the hole-like Fermi surface sheets, no quasiparticle peak is present in the normal state. Its electronic behaviours deviate strongly from a Fermi liquid system. The superconducting gap of such a system exhibits an unusual temperature dependence that it is nearly a constant in the superconducting state and abruptly closes at Tc. These observations have provided a new platform to study unconventional superconductivity in a non-Fermi liquid system.
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Project supported by the National Natural Science Foundation of China (Grant Nos. 11264018 and 60978009)the Major Research Plan of the National Natural Science Foundation of China (Grant No. 91121023)+1 种基金the National Basic Research Project of China (Grant No. 2011CBA00200)the Young Talents Foundation of Jiangxi Normal University,China
文摘For the first time,we derive the compact forms of normalization factors for photon-added（-subtracted） two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators（IWOP） technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10647132 and 11104113)the Scientific Research Fund of Hunan Provincial Education Department of China (Grant No. 10A100)
文摘Optomechanical dynamics in two systems which are a transmission line resonator and Fabrya-Perot optical cavity via radiation-pressure are investigated by linearized quantum Langevin equation. We work in the resolved sideband regime where the oscillator resonance frequency exceeds the cavity linewidth. Normal mode splittings of the mechanical resonator as a pure result of the coupling interaction in the two optomechanical systems is studied, and we make a comparison of normal mode splitting of mechanical resonator between the two systems. In the optical cavity, the normal mode splitting of the movable mirror approaches the latest experiment very well. In addition, an approximation scheme is introduced to demonstrate the ground state cooling, and we make a comparison of cooling between the two systems dominated by two key factors, which are the initial bath temperature and the mechanical quality factor. Since both the normal mode splitting and cooling require working in the resolved sideband regime, whether the normal mode splitting influences the cooling of the mirror is considered. Considering the size of the mechanical resonator and precooling the system, the mechanical resonator in the transmission line resonator system is easier to achieve the ground state cooling than in optical cavity.
