In the paper,an experiment investigation was conducted for one-and two-degree of freedom vortex-induced vibration（VIV） of a horizontally-oriented cylinder with diameter of 11 cm and length of 120 cm.In the experimen...In the paper,an experiment investigation was conducted for one-and two-degree of freedom vortex-induced vibration（VIV） of a horizontally-oriented cylinder with diameter of 11 cm and length of 120 cm.In the experiment,the spring constants in the cross-flow and in-line flow directions were regulated to change the natural vibration frequency of the model system.It was found that,in the one-degree of freedom VIV experiment,a ＂double peak＂ phenomenon was observed in its amplitude within the range of the reduced velocities tested,moreover,a ＂2T＂ wake appeared in the vicinity of the second peak.In the two-degree of freedom VIV experiment,the trajectory of cylinder exhibited a reverse ＂C＂ shape,i.e.,a ＂new moon＂ shape.Through analysis of these data,it appears that,besides the non-dimensional in-line and cross-flow natural vibration frequency ratios,the absolute value of the natural vibration frequency of cylinder is also one of the important parameters affecting its VIV behavior.展开更多
By virtue of the technique of integration within an ordered product of operators, we derive the normal ordering expansion of a one- and two-mode combination squeezing operator for two harmonic oscillators with coordin...By virtue of the technique of integration within an ordered product of operators, we derive the normal ordering expansion of a one- and two-mode combination squeezing operator for two harmonic oscillators with coordinate- momentum coupling. It turns out that this squeezing operator just diagonalizes the Hamiltonian H=p^21/2m1＋m1ω^21x^21/2＋p^222m2＋m2ω^22x^22/2-λx2p1 so its ground state is a one- and two-mode combination squeezed state. Quantum fluctuation in the ground state is calculated.展开更多
Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems （SCPCSs）. As the system parameters change, different patterns are obtained from the period-doubling of k...Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems （SCPCSs）. As the system parameters change, different patterns are obtained from the period-doubling of kink-antikinks in space to the spatiotemporal chaos in a one-dimensional SCPCS. The homogeneous symmetric states induce symmetry breaking from the four corners and the boundaries, finally leading to spatiotemporal chaos with the increase of the iteration time in a two-dimensional SCPCS. Numerical simulations are very helpful for understanding the complex optical phenomena.展开更多
This article is concerned with the problem of prediction for the future generalized order statistics from a mixture of two general components based on doubly?type II censored sample. We consider the one sample predict...This article is concerned with the problem of prediction for the future generalized order statistics from a mixture of two general components based on doubly?type II censored sample. We consider the one sample prediction and two sample prediction techniques. Bayesian prediction intervals for the median of future sample of generalized order statistics having odd and even sizes are obtained. Our results are specialized to ordinary order statistics and ordinary upper record values. A mixture of two Gompertz components model is given as an application. Numerical computations are given to illustrate the procedures.展开更多
Bayesian predictive probability density function is obtained when the underlying pop-ulation distribution is exponentiated and subjective prior is used. The corresponding predictive survival function is then obtained ...Bayesian predictive probability density function is obtained when the underlying pop-ulation distribution is exponentiated and subjective prior is used. The corresponding predictive survival function is then obtained and used in constructing 100(1 – ?)% predictive interval, using one- and two- sample schemes when the size of the future sample is fixed and random. In the random case, the size of the future sample is assumed to follow the truncated Poisson distribution with parameter λ. Special attention is paid to the exponentiated Burr type XII population, from which the data are drawn. Two illustrative examples are given, one of which uses simulated data and the other uses data that represent the breaking strength of 64 single carbon fibers of length 10, found in Lawless [40].展开更多
For the principal eigenvalue with bilateral Dirichlet boundary condition, the so-called basic estimates were originally obtained by capacitary method. The Neumann case （i.e., the ergodic case） is even harder, and wa...For the principal eigenvalue with bilateral Dirichlet boundary condition, the so-called basic estimates were originally obtained by capacitary method. The Neumann case （i.e., the ergodic case） is even harder, and was deduced from the Dirichlet one plus a use of duality and the coupling method. In this paper, an alternative and more direct proof for the basic estimates is presented. The estimates in the Dirichlet case are then improved by a typical application of a recent variational formula. As a dual of the Dirichlet case, the refine problem for bilateral Neumann boundary condition is also treated. The paper starts with the continuous case （one-dimensional diffusions） and ends at the discrete one （birth-death processes）. Possible generalization of the results studied here is discussed at the end of the paper展开更多
High-entropy-oxides(HEOs),a new class of solids that contain five or more elemental species,have attracted increasing interests owing to their unique structures and fascinating physicochemical properties.However,it is...High-entropy-oxides(HEOs),a new class of solids that contain five or more elemental species,have attracted increasing interests owing to their unique structures and fascinating physicochemical properties.However,it is a huge challenge to construct various nanostructured,especially low-dimensional nanostructured HEOs under the high temperature synthetic conditions.Herein,a facile strategy using glucose-urea deep eutectic solvent(DES)as both a solvent and the carbon source of structure-directed template is proposed for the synthesis of various HEOs with two-dimentional(2D)nanonets and one-dimentional(1D)nanowires,including rock-salt(Co,Cu,Mg,Ni,Zn)O,spinel(Co,Cr,Fe,Mn,Ni)_(3)O_(4),and perovskite La(Co,Cr,Fe,Mn,Ni)O_(3).The as-prepared HEOs possessed five or more uniformly dispersed metal elements,large specific surface areas(more than 25 m^(2)·g^(−1)),and a pure single-phase structure.In addition,high cooling rate(cooling in air or liq-N_(2)-quenching)was indispensable to obtain a single-phase rock-salt(Co,Cu,Mg,Ni,Zn)O because of phase separation caused by copper.By taking advantage of unique features of HEOs,rock-salt(Co,Cu,Mg,Ni,Zn)O can function as a promising candidate for lithium-ion batteries(LIBs)anode material,which achieved excellent cycling stability.This work provides a feasible synthetic strategy for low-dimensional hierarchical HEOs,which creates new opportunities for the stable HEOs being highly active functional materials.展开更多
Two novel one- and two-dimensional network structure bismuth(III) complexes with N,N-di(2-hydroxylethyl)- aminodithiocarboxylate, {Bi[S2CN(C2H4OH)2]2[1,10-Phen]2(NO3)}3H2O (1) and {Bi[S2CN(C2H4OH)2]3}2 (2) were synthe...Two novel one- and two-dimensional network structure bismuth(III) complexes with N,N-di(2-hydroxylethyl)- aminodithiocarboxylate, {Bi[S2CN(C2H4OH)2]2[1,10-Phen]2(NO3)}3H2O (1) and {Bi[S2CN(C2H4OH)2]3}2 (2) were synthesized. Their crystal and molecular structures were determined by X-ray single crystal diffraction analysis. The crystal 1 belongs to monoclinic system with space group C2/c, a=1.6431(7) nm, b=2.4323(10) nm, c=1.2646(5) nm, =126.237(5)o, Z=4, V=4.076(3) nm3, Dc=1.757 Mg/m3, =4.598 mm-1, F(000)=2156, R=0.0211, wR=0.0369. The structure shows a distorted square antiprism configuration with eight-coordination for the central Bi atom. The one-dimensional chain structure was formed by H-bonding interaction between hydroxyl group of N,N-di(2-hydroxylethyl)aminodithiocarboxylate ligands and crystal water. The crystal 2 belongs to monoclinic system with space group P2(1)/c, a=1.1149(4) nm, b=2.1274(8) nm, c=2.2107(8) nm, =98.325(8), Z=4, V=5.188(3) nm3, Dc=1.920 Mg/m3, =7.315 mm-1, F(000)=2944, R=0.0565, wR=0.0772. The structure shows a distorted square antiprism configuration with eight-coordination for the central Bi atoms. The two-dimensional network structure was formed by H-bonding interaction between adjacent molecules.展开更多
基金supported by the National Natural Science Foundation of China (51009033)the Fundamental Research Funds for the Central Universities
文摘In the paper,an experiment investigation was conducted for one-and two-degree of freedom vortex-induced vibration（VIV） of a horizontally-oriented cylinder with diameter of 11 cm and length of 120 cm.In the experiment,the spring constants in the cross-flow and in-line flow directions were regulated to change the natural vibration frequency of the model system.It was found that,in the one-degree of freedom VIV experiment,a ＂double peak＂ phenomenon was observed in its amplitude within the range of the reduced velocities tested,moreover,a ＂2T＂ wake appeared in the vicinity of the second peak.In the two-degree of freedom VIV experiment,the trajectory of cylinder exhibited a reverse ＂C＂ shape,i.e.,a ＂new moon＂ shape.Through analysis of these data,it appears that,besides the non-dimensional in-line and cross-flow natural vibration frequency ratios,the absolute value of the natural vibration frequency of cylinder is also one of the important parameters affecting its VIV behavior.
文摘By virtue of the technique of integration within an ordered product of operators, we derive the normal ordering expansion of a one- and two-mode combination squeezing operator for two harmonic oscillators with coordinate- momentum coupling. It turns out that this squeezing operator just diagonalizes the Hamiltonian H=p^21/2m1＋m1ω^21x^21/2＋p^222m2＋m2ω^22x^22/2-λx2p1 so its ground state is a one- and two-mode combination squeezed state. Quantum fluctuation in the ground state is calculated.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10847110)
文摘Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems （SCPCSs）. As the system parameters change, different patterns are obtained from the period-doubling of kink-antikinks in space to the spatiotemporal chaos in a one-dimensional SCPCS. The homogeneous symmetric states induce symmetry breaking from the four corners and the boundaries, finally leading to spatiotemporal chaos with the increase of the iteration time in a two-dimensional SCPCS. Numerical simulations are very helpful for understanding the complex optical phenomena.
文摘This article is concerned with the problem of prediction for the future generalized order statistics from a mixture of two general components based on doubly?type II censored sample. We consider the one sample prediction and two sample prediction techniques. Bayesian prediction intervals for the median of future sample of generalized order statistics having odd and even sizes are obtained. Our results are specialized to ordinary order statistics and ordinary upper record values. A mixture of two Gompertz components model is given as an application. Numerical computations are given to illustrate the procedures.
文摘Bayesian predictive probability density function is obtained when the underlying pop-ulation distribution is exponentiated and subjective prior is used. The corresponding predictive survival function is then obtained and used in constructing 100(1 – ?)% predictive interval, using one- and two- sample schemes when the size of the future sample is fixed and random. In the random case, the size of the future sample is assumed to follow the truncated Poisson distribution with parameter λ. Special attention is paid to the exponentiated Burr type XII population, from which the data are drawn. Two illustrative examples are given, one of which uses simulated data and the other uses data that represent the breaking strength of 64 single carbon fibers of length 10, found in Lawless [40].
基金This work was supported in part by the National Natural Science Foundation of China （Grant No. 11131003） and the ＂985＂ Project from the Ministry of Education in China.
文摘For the principal eigenvalue with bilateral Dirichlet boundary condition, the so-called basic estimates were originally obtained by capacitary method. The Neumann case （i.e., the ergodic case） is even harder, and was deduced from the Dirichlet one plus a use of duality and the coupling method. In this paper, an alternative and more direct proof for the basic estimates is presented. The estimates in the Dirichlet case are then improved by a typical application of a recent variational formula. As a dual of the Dirichlet case, the refine problem for bilateral Neumann boundary condition is also treated. The paper starts with the continuous case （one-dimensional diffusions） and ends at the discrete one （birth-death processes）. Possible generalization of the results studied here is discussed at the end of the paper
基金the Nationla Key R&D Program of China(No.2016YFA0203203)the National Natural Science Foundation of China(Nos.22074137 and 21721003).
文摘High-entropy-oxides(HEOs),a new class of solids that contain five or more elemental species,have attracted increasing interests owing to their unique structures and fascinating physicochemical properties.However,it is a huge challenge to construct various nanostructured,especially low-dimensional nanostructured HEOs under the high temperature synthetic conditions.Herein,a facile strategy using glucose-urea deep eutectic solvent(DES)as both a solvent and the carbon source of structure-directed template is proposed for the synthesis of various HEOs with two-dimentional(2D)nanonets and one-dimentional(1D)nanowires,including rock-salt(Co,Cu,Mg,Ni,Zn)O,spinel(Co,Cr,Fe,Mn,Ni)_(3)O_(4),and perovskite La(Co,Cr,Fe,Mn,Ni)O_(3).The as-prepared HEOs possessed five or more uniformly dispersed metal elements,large specific surface areas(more than 25 m^(2)·g^(−1)),and a pure single-phase structure.In addition,high cooling rate(cooling in air or liq-N_(2)-quenching)was indispensable to obtain a single-phase rock-salt(Co,Cu,Mg,Ni,Zn)O because of phase separation caused by copper.By taking advantage of unique features of HEOs,rock-salt(Co,Cu,Mg,Ni,Zn)O can function as a promising candidate for lithium-ion batteries(LIBs)anode material,which achieved excellent cycling stability.This work provides a feasible synthetic strategy for low-dimensional hierarchical HEOs,which creates new opportunities for the stable HEOs being highly active functional materials.
基金Project supported by the National Natural Science Foundation of China (No. 20271025) and the Natural Science Foundation of Shandong Province (No. L2003B01).
文摘Two novel one- and two-dimensional network structure bismuth(III) complexes with N,N-di(2-hydroxylethyl)- aminodithiocarboxylate, {Bi[S2CN(C2H4OH)2]2[1,10-Phen]2(NO3)}3H2O (1) and {Bi[S2CN(C2H4OH)2]3}2 (2) were synthesized. Their crystal and molecular structures were determined by X-ray single crystal diffraction analysis. The crystal 1 belongs to monoclinic system with space group C2/c, a=1.6431(7) nm, b=2.4323(10) nm, c=1.2646(5) nm, =126.237(5)o, Z=4, V=4.076(3) nm3, Dc=1.757 Mg/m3, =4.598 mm-1, F(000)=2156, R=0.0211, wR=0.0369. The structure shows a distorted square antiprism configuration with eight-coordination for the central Bi atom. The one-dimensional chain structure was formed by H-bonding interaction between hydroxyl group of N,N-di(2-hydroxylethyl)aminodithiocarboxylate ligands and crystal water. The crystal 2 belongs to monoclinic system with space group P2(1)/c, a=1.1149(4) nm, b=2.1274(8) nm, c=2.2107(8) nm, =98.325(8), Z=4, V=5.188(3) nm3, Dc=1.920 Mg/m3, =7.315 mm-1, F(000)=2944, R=0.0565, wR=0.0772. The structure shows a distorted square antiprism configuration with eight-coordination for the central Bi atoms. The two-dimensional network structure was formed by H-bonding interaction between adjacent molecules.
