For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al...For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem.展开更多
In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate ...In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate the time constant of a semiconductor survey meter and confirm the meter’s function. An additional filter was attached to the medical X-ray system to satisfy the standards of N-60 to N-120, more copper plates were added as needed, and the first and second half-value layers were calculated to enable comparisons of the facility’s X-ray system quality with the N-60 to N-120 quality values. Next, we used a medical X-ray system to measure the leakage dose and calculate the time constant of the survey meter. The functionality of the meter was then checked and compared with the energy characteristics of the meter. The experimental results showed that it was possible to use a medical X-ray system to reproduce the N-60 to N-120 radiation quality values and to calculate the time constant from the measured results, assuming actual leakage dosimetry for that radiation quality. We also found that the calibration factor was equivalent to that of the energy characteristics of the survey meter.展开更多
Series of exponential equations in the form of were solved graphically, numerically and analytically. The analytical solution was derived in terms of Lambert-W function. A general numerical solution for any y is found...Series of exponential equations in the form of were solved graphically, numerically and analytically. The analytical solution was derived in terms of Lambert-W function. A general numerical solution for any y is found in terms of n or in base y. A solution is close to the fine structure constant. The equation which provided the solution as the fine structure constant was derived in terms of the fundamental constants.展开更多
Thermodynamic dissociation constants pKa of 2,2-bis(hydroxymethyl)-2,2’,2”-nitrilotriethanol have been determined at 12 temperatures from (278.15 to 328.15) K including the body temperature 310.15 K by the electromo...Thermodynamic dissociation constants pKa of 2,2-bis(hydroxymethyl)-2,2’,2”-nitrilotriethanol have been determined at 12 temperatures from (278.15 to 328.15) K including the body temperature 310.15 K by the electromotive-force measurements (emf) of hydrogen-silver chloride cells without liquid junction of the type: Pt(s), H2(g), 101.325 kPa|BIS-TRIS (m) + BIS-TRIS·HCl (m)| AgCl(s), Ag(s), where m denotes molality. The pKa values for the dissociation process of BIS-TRIS·H++ H2O = H3O+ + BIS-TRIS given as a function of T in Kelvin (K) by the equation pKa = 921.66 (K/T) + 14.0007-1.86197 ln(T/K). At 298.15 and 310.15 K, the values of pKa for BIS-TRIS were found to be 6.4828 ± 0.0005 and 6.2906 ± 0.0006 respectively. Thus buffer solutions composed of BIS-TRIS and its hydrochloride would be useful as secondary pH buffer standards and for control of acidity in the pH range 6 to 8. At 298.15 K the thermodynamic functions G°, H°, S° and Cp° for the dissociation process of BIS-TRIS·H+ are G°=37,005 J·mol-1, H° = 28,273 J·mol-1, S°= 29.3 J·K-1·mol-1 and Cp° = 36 J·K-1·mol-1. These results are compared with the dissociation of protonated bases structurally related to BIS-TRIS·H+.展开更多
Two-dimensional function photonic crystals, in which the dielectric constants of medium columns are the functions of space coordinates , are proposed and studied numerically. The band gaps structures of the photonic c...Two-dimensional function photonic crystals, in which the dielectric constants of medium columns are the functions of space coordinates , are proposed and studied numerically. The band gaps structures of the photonic crystals for TE and TM waves are different from the two-dimensional conventional photonic crystals. Some absolute band gaps and semiDirac points are found. When the medium column radius and the function form of the dielectric constant are modulated, the numbers, width, and position of band gaps are changed, and the semi-Dirac point can either occur or disappear. Therefore,the special band gaps structures and semi-Dirac points can be achieved through the modulation on the two-dimensional function photonic crystals. The results will provide a new design method of optical devices based on the two-dimensional function photonic crystals.展开更多
In this paper,we use the theory of value distribution and study the uniqueness of meromorphic functions.We will prove the following result:Let f(z)and g(z)be two transcendental meromorphic functions,p(z)a polynomial o...In this paper,we use the theory of value distribution and study the uniqueness of meromorphic functions.We will prove the following result:Let f(z)and g(z)be two transcendental meromorphic functions,p(z)a polynomial of degree k,n≥max{11,k+1}a positive integer.If fn(z)f(z)and gn(z)g(z)share p(z)CM,then either f(z)=c1ec p(z)dz, g(z)=c2e ?c p(z)dz ,where c1,c2 and c are three constants satisfying(c1c2) n+1 c2=-1 or f(z)≡tg(z)for a constant t such that tn+1=1.展开更多
Properties of Lebesgue function for Lagrange interpolation on equidistant nodes are investigated. It is proved that Lebesgue function can be formulated both in terms of a hypergeometric function 2F1 and Jacobi polynom...Properties of Lebesgue function for Lagrange interpolation on equidistant nodes are investigated. It is proved that Lebesgue function can be formulated both in terms of a hypergeometric function 2F1 and Jacobi polynomials. Moreover, an integral expression of Lebesgue function is also obtained and the asymptotic behavior of Lebesgue constant is studied.展开更多
Structural and thermodynamic parameters of 16 chloro-phenol compounds in water solution were calculated and fully optimized by using Onsager model in self-consistent reaction field(SCRF) based on the B3LYP/6-311G*...Structural and thermodynamic parameters of 16 chloro-phenol compounds in water solution were calculated and fully optimized by using Onsager model in self-consistent reaction field(SCRF) based on the B3LYP/6-311G** level.These quantum chemical parameters were used as theoretical descriptors to correlate with the experimental biodegradation rate constant(Kb) of 16 compounds by stepwise multiple linear regression.As a result,a three-parameter model including molecular average polarizability(α),entropy(Sθ),and molar heat capacity at constant volume(CVθ) were established for Kb prediction,which was proposed with correlation coefficient R2 = 0.894.α exhibits the most significant effect on Kb.Variance analysis and standard t-value test were applied to validate the model.As expected,this model exhibits good robustness and prediction ability,which can be used in Kb prediction of analogs.展开更多
带脉冲恒功率负载的直流供电系统(DC power supply system with pulse constant power load,PCPL-DCPS)运行过程随脉冲参数的变化包含多种不同运行状态。目前电力系统单模态大信号稳定性分析方法无法适用于中高频状态脉冲负载的稳定性...带脉冲恒功率负载的直流供电系统(DC power supply system with pulse constant power load,PCPL-DCPS)运行过程随脉冲参数的变化包含多种不同运行状态。目前电力系统单模态大信号稳定性分析方法无法适用于中高频状态脉冲负载的稳定性分析。为此,提出了一种结合切换理论和混合势函数法的统一大信号稳定性分析方法。该方法以快慢切换驻留时间为界,划分了切换系统快慢切换稳定域,并以满足不同驻留时间为条件,提出不同域的大信号稳定性分析原则。以PCPL-DCPS为研究对象进行仿真试验,对比单模态稳定性判据和渐进稳定域域界,验证了快慢切换稳定域界划分和分析方法更合理,并进一步将切换系统稳定性与脉冲频率关联,得到了更为统一和直观的表达式。所述方法适用于全时段的切换电力系统,也可扩展应用到带脉冲负载的交流供电系统的稳定性研究中,进一步指导脉冲负载的峰值功率、脉冲频率等参数的选取。展开更多
文摘For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem.
文摘In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate the time constant of a semiconductor survey meter and confirm the meter’s function. An additional filter was attached to the medical X-ray system to satisfy the standards of N-60 to N-120, more copper plates were added as needed, and the first and second half-value layers were calculated to enable comparisons of the facility’s X-ray system quality with the N-60 to N-120 quality values. Next, we used a medical X-ray system to measure the leakage dose and calculate the time constant of the survey meter. The functionality of the meter was then checked and compared with the energy characteristics of the meter. The experimental results showed that it was possible to use a medical X-ray system to reproduce the N-60 to N-120 radiation quality values and to calculate the time constant from the measured results, assuming actual leakage dosimetry for that radiation quality. We also found that the calibration factor was equivalent to that of the energy characteristics of the survey meter.
文摘Series of exponential equations in the form of were solved graphically, numerically and analytically. The analytical solution was derived in terms of Lambert-W function. A general numerical solution for any y is found in terms of n or in base y. A solution is close to the fine structure constant. The equation which provided the solution as the fine structure constant was derived in terms of the fundamental constants.
文摘Thermodynamic dissociation constants pKa of 2,2-bis(hydroxymethyl)-2,2’,2”-nitrilotriethanol have been determined at 12 temperatures from (278.15 to 328.15) K including the body temperature 310.15 K by the electromotive-force measurements (emf) of hydrogen-silver chloride cells without liquid junction of the type: Pt(s), H2(g), 101.325 kPa|BIS-TRIS (m) + BIS-TRIS·HCl (m)| AgCl(s), Ag(s), where m denotes molality. The pKa values for the dissociation process of BIS-TRIS·H++ H2O = H3O+ + BIS-TRIS given as a function of T in Kelvin (K) by the equation pKa = 921.66 (K/T) + 14.0007-1.86197 ln(T/K). At 298.15 and 310.15 K, the values of pKa for BIS-TRIS were found to be 6.4828 ± 0.0005 and 6.2906 ± 0.0006 respectively. Thus buffer solutions composed of BIS-TRIS and its hydrochloride would be useful as secondary pH buffer standards and for control of acidity in the pH range 6 to 8. At 298.15 K the thermodynamic functions G°, H°, S° and Cp° for the dissociation process of BIS-TRIS·H+ are G°=37,005 J·mol-1, H° = 28,273 J·mol-1, S°= 29.3 J·K-1·mol-1 and Cp° = 36 J·K-1·mol-1. These results are compared with the dissociation of protonated bases structurally related to BIS-TRIS·H+.
基金Project supported by the National Natural Science Foundations of China(Grant No.61275047)the Research Project of Chinese Ministry of Education(Grant No.213009A)the Scientific and Technological Development Foundation of Jilin Province,China(Grant No.20130101031JC)
文摘Two-dimensional function photonic crystals, in which the dielectric constants of medium columns are the functions of space coordinates , are proposed and studied numerically. The band gaps structures of the photonic crystals for TE and TM waves are different from the two-dimensional conventional photonic crystals. Some absolute band gaps and semiDirac points are found. When the medium column radius and the function form of the dielectric constant are modulated, the numbers, width, and position of band gaps are changed, and the semi-Dirac point can either occur or disappear. Therefore,the special band gaps structures and semi-Dirac points can be achieved through the modulation on the two-dimensional function photonic crystals. The results will provide a new design method of optical devices based on the two-dimensional function photonic crystals.
基金Supported by the Natural Science Foundation of Jiangsu Education Department(07KJD110086)
文摘In this paper,we use the theory of value distribution and study the uniqueness of meromorphic functions.We will prove the following result:Let f(z)and g(z)be two transcendental meromorphic functions,p(z)a polynomial of degree k,n≥max{11,k+1}a positive integer.If fn(z)f(z)and gn(z)g(z)share p(z)CM,then either f(z)=c1ec p(z)dz, g(z)=c2e ?c p(z)dz ,where c1,c2 and c are three constants satisfying(c1c2) n+1 c2=-1 or f(z)≡tg(z)for a constant t such that tn+1=1.
文摘Properties of Lebesgue function for Lagrange interpolation on equidistant nodes are investigated. It is proved that Lebesgue function can be formulated both in terms of a hypergeometric function 2F1 and Jacobi polynomials. Moreover, an integral expression of Lebesgue function is also obtained and the asymptotic behavior of Lebesgue constant is studied.
基金Supported by the State Key Program of NNSFC (No. 20737001)NNSFC (No. 20977044)
文摘Structural and thermodynamic parameters of 16 chloro-phenol compounds in water solution were calculated and fully optimized by using Onsager model in self-consistent reaction field(SCRF) based on the B3LYP/6-311G** level.These quantum chemical parameters were used as theoretical descriptors to correlate with the experimental biodegradation rate constant(Kb) of 16 compounds by stepwise multiple linear regression.As a result,a three-parameter model including molecular average polarizability(α),entropy(Sθ),and molar heat capacity at constant volume(CVθ) were established for Kb prediction,which was proposed with correlation coefficient R2 = 0.894.α exhibits the most significant effect on Kb.Variance analysis and standard t-value test were applied to validate the model.As expected,this model exhibits good robustness and prediction ability,which can be used in Kb prediction of analogs.
文摘带脉冲恒功率负载的直流供电系统(DC power supply system with pulse constant power load,PCPL-DCPS)运行过程随脉冲参数的变化包含多种不同运行状态。目前电力系统单模态大信号稳定性分析方法无法适用于中高频状态脉冲负载的稳定性分析。为此,提出了一种结合切换理论和混合势函数法的统一大信号稳定性分析方法。该方法以快慢切换驻留时间为界,划分了切换系统快慢切换稳定域,并以满足不同驻留时间为条件,提出不同域的大信号稳定性分析原则。以PCPL-DCPS为研究对象进行仿真试验,对比单模态稳定性判据和渐进稳定域域界,验证了快慢切换稳定域界划分和分析方法更合理,并进一步将切换系统稳定性与脉冲频率关联,得到了更为统一和直观的表达式。所述方法适用于全时段的切换电力系统,也可扩展应用到带脉冲负载的交流供电系统的稳定性研究中,进一步指导脉冲负载的峰值功率、脉冲频率等参数的选取。