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Analysis of a Laplace Spectral Method for Time-Fractional Advection-Diffusion Equations Incorporating the Atangana-Baleanu Derivative
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作者 Kamran Farman Ali Shah +3 位作者 Kallekh Afef J.F.Gómez-Aguilar Salma Aljawi Ioan-Lucian Popa 《Computer Modeling in Engineering & Sciences》 2025年第6期3433-3462,共30页
In this article,we develop the Laplace transform(LT)based Chebyshev spectral collocation method(CSCM)to approximate the time fractional advection-diffusion equation,incorporating the Atangana-Baleanu Caputo(ABC)deriva... In this article,we develop the Laplace transform(LT)based Chebyshev spectral collocation method(CSCM)to approximate the time fractional advection-diffusion equation,incorporating the Atangana-Baleanu Caputo(ABC)derivative.The advection-diffusion equation,which governs the transport of mass,heat,or energy through combined advection and diffusion processes,is central to modeling physical systems with nonlocal behavior.Our numerical scheme employs the LT to transform the time-dependent time-fractional PDEs into a time-independent PDE in LT domain,eliminating the need for classical time-stepping methods that often suffer from stability constraints.For spatial discretization,we employ the CSCM,where the solution is approximated using Lagrange interpolation polynomial based on the Chebyshev collocation nodes,achieving exponential convergence that outperforms the algebraic convergence rates of finite difference and finite element methods.Finally,the solution is reverted to the time domain using contour integration technique.We also establish the existence and uniqueness of the solution for the proposed problem.The performance,efficiency,and accuracy of the proposed method are validated through various fractional advection-diffusion problems.The computed results demonstrate that the proposed method has less computational cost and is highly accurate. 展开更多
关键词 Laplace transform spectral method existence theory fractional derivative with non-singular kernel contour integration methods
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Validation Analysis of Gas Chromatography Method for Determining 8 Benzene Derivatives in Fixed Pollution Source Exhaust Gas
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作者 Wenshuai XU Juan LI Ziyan LIN 《Meteorological and Environmental Research》 2025年第4期37-39,42,共4页
Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment... Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment management.In this paper,Shimadzu Nexis GC-2030 gas chromatography was used to simultaneously detect eight benzene derivatives.According to the Environmental Monitoring—Technical Guideline on Drawing and Revising Analytical Method Standards(HJ 168-2010),the monitoring methods for benzene,toluene,ethylbenzene,p-xylene,m-xylene,isopropylbenzene,o-xylene,and styrene in the Stationary Source Emission—Determination of Benzene and Its Analogies—Bags Sampling/Direct Injection—Gas Chromatography(HJ 1261-2022)are verified,and their linear relationships,detection limits,precision and accuracy are analyzed. 展开更多
关键词 Benzene derivatives Fixed pollution source exhaust gas method validation
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A NEW DERIVATIVE FREE OPTIMIZATION METHOD BASED ON CONIC INTERPOLATION MODEL 被引量:9
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作者 倪勤 胡书华 《Acta Mathematica Scientia》 SCIE CSCD 2004年第2期281-290,共10页
In this paper, a new derivative free trust region method is developed based on the conic interpolation model for the unconstrained optimization. The conic interpolation model is built by means of the quadratic model f... In this paper, a new derivative free trust region method is developed based on the conic interpolation model for the unconstrained optimization. The conic interpolation model is built by means of the quadratic model function, the collinear scaling formula, quadratic approximation and interpolation. All the parameters in this model are determined by objective function interpolation condition. A new derivative free method is developed based upon this model and the global convergence of this new method is proved without any information on gradient. 展开更多
关键词 derivative free optimization method conic interpolation model quadratic interpolation model trust region method unconstrained optimization
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A FAMILY OF MODAL METHODS FOR COMPUTING EIGENVECTOR DERIVATIVES WITH REPEATED ROOTS 被引量:2
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作者 王文亮 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1996年第2期158-168,共11页
A family of modal methods for computing eigenvector derivatives with repeated roots are directly derived from the constraint generalized inverse technique which is originally formulated by Wang and Hu. Extensions are ... A family of modal methods for computing eigenvector derivatives with repeated roots are directly derived from the constraint generalized inverse technique which is originally formulated by Wang and Hu. Extensions are made to Akgun's method to allow treatment of eigensensitivity with repeated roots for general nondefective systems, and Bernard and Bronowicki's modal expansion approach is expanded to a family of modal methods. 展开更多
关键词 a family of modal methods nondefective system eigenvector derivative eigensensitivity with repeated roots
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Non-intrusive hybrid interval method for uncertain nonlinear systems using derivative information 被引量:1
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作者 Zhuang-Zhuang Liu Tian-ShuWang Jun-Feng Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期170-180,共11页
This paper proposes a new non-intrusive hybrid interval method using derivative information for the dynamic response analysis of nonlinear systems with uncertain-but- bounded parameters and/or initial conditions. This... This paper proposes a new non-intrusive hybrid interval method using derivative information for the dynamic response analysis of nonlinear systems with uncertain-but- bounded parameters and/or initial conditions. This method provides tighter solution ranges compared to the existing polynomial approximation interval methods. Interval arith- metic using the Chebyshev basis and interval arithmetic using the general form modified affine basis for polynomials are developed to obtain tighter bounds for interval computation. To further reduce the overestimation caused by the "wrap- ping effect" of interval arithmetic, the derivative information of dynamic responses is used to achieve exact solutions when the dynamic responses are monotonic with respect to all the uncertain variables. Finally, two typical numerical examples with nonlinearity are applied to demonstrate the effective- ness of the proposed hybrid interval method, in particular, its ability to effectively control the overestimation for specific timepoints. 展开更多
关键词 Non-intrusive hybrid interval method Dynamic response analysis Uncertain nonlinear systems Polynomial approximation Interval arithmetic derivative information
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The Efficient Finite Element Methods for Time-Fractional Oldroyd-B Fluid Model Involving Two Caputo Derivatives 被引量:2
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作者 An Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期173-195,共23页
In this paper,we consider the numerical schemes for a timefractionalOldroyd-B fluidmodel involving the Caputo derivative.We propose two efficient finite element methods by applying the convolution quadrature in time g... In this paper,we consider the numerical schemes for a timefractionalOldroyd-B fluidmodel involving the Caputo derivative.We propose two efficient finite element methods by applying the convolution quadrature in time generated by the backward Euler and the second-order backward difference methods.Error estimates in terms of data regularity are established for both the semidiscrete and fully discrete schemes.Numerical examples for two-dimensional problems further confirmthe robustness of the schemes with first-and second-order accurate in time. 展开更多
关键词 Oldroyd-B fluid model caputo derivative finite element method convolution quadrature error estimate data regularity
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A NEW METHOD FOR THE PREPARATION OF PHENOLS AND ITS DERIVATIVES 被引量:1
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作者 Qun LIU Kocienski PHILIP 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期353-356,共4页
a-Oxo ketene dithioacetals 2 via 1,2-nucleophilie addition by methallyl magnesius chloride afforded corresponding alcohols (3). Treated with water or methanol and catalyzed by Lewis acid, the alcohols 3 were converted... a-Oxo ketene dithioacetals 2 via 1,2-nucleophilie addition by methallyl magnesius chloride afforded corresponding alcohols (3). Treated with water or methanol and catalyzed by Lewis acid, the alcohols 3 were converted regiospecifical ly to substituted phenols 5' or related phenol methyl ethers 5 respectively. This reaction is a novel approach to the synthesis of phenols and their derivatives starting from non-aromatic precursors. 展开更多
关键词 A NEW method FOR THE PREPARATION OF PHENOLS AND ITS derivativeS ITS
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Local Discontinuous Galerkin Method for the Time-Fractional KdV Equation with the Caputo-Fabrizio Fractional Derivative 被引量:1
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作者 Huanhuan Wang Xiaoyan Xu +2 位作者 Junmei Dou Ting Zhang Leilei Wei 《Journal of Applied Mathematics and Physics》 2022年第6期1918-1935,共18页
This paper studies the time-fractional Korteweg-de Vries (KdV) equations with Caputo-Fabrizio fractional derivatives. The scheme is presented by using a finite difference method in temporal variable and a local discon... This paper studies the time-fractional Korteweg-de Vries (KdV) equations with Caputo-Fabrizio fractional derivatives. The scheme is presented by using a finite difference method in temporal variable and a local discontinuous Galerkin method (LDG) in space. Stability and convergence are demonstrated by a specific choice of numerical fluxes. Finally, the efficiency and accuracy of the scheme are verified by numerical experiments. 展开更多
关键词 Caputo-Fabrizio Fractional derivative Local Discontinuous Galerkin method STABILITY Error Analysis
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A NEW GENERAL OPTIMAL PRINCIPLE OF DESIGNING EXPLICIT FINITE DIFFERENCE METHOD FOR VALUING DERIVATIVE SECURITIES
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作者 Jiangping Peng (1) Weiping Xiong (1) +1 位作者 Songren Li (2) Qingfeng Guo (2) (3) 《Journal of Central South University》 SCIE EI CAS 1999年第2期142-144,共3页
A new general optimal principle of designing explicit finite difference method was obtained. Several applied cases were put forward to explain the uses of the principle. The validity of the principal was tested by a n... A new general optimal principle of designing explicit finite difference method was obtained. Several applied cases were put forward to explain the uses of the principle. The validity of the principal was tested by a numeric example. 展开更多
关键词 derivative security explicit FINITE DIFFERENCE method IMPLICIT FINITE DIFFERENCE method numerical method
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ON FICTITIOUS DOMAIN METHOD FOR THE NUMERICAL SOLUTION TO HEAT CONDUCTION EQUATION WITH DERIVATIVE BOUNDARY CONDITIONS
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作者 孙志忠 《Journal of Southeast University(English Edition)》 EI CAS 1993年第2期38-44,共7页
This paper investigates the stability and convergence of some knowndifference schemes for the numerical solution to heat conduction equation withderivative boundary conditions by the fictitious domain method.The discr... This paper investigates the stability and convergence of some knowndifference schemes for the numerical solution to heat conduction equation withderivative boundary conditions by the fictitious domain method.The discrete vari-ables at the false mesh points are firstly eliminated from the difference schemes andthe local truncation errors are then analyzed in detail.The stability and convergenceof the schemes are proved by energy method.An improvement is proposed to obtainbetter schemes over the original ones.Several numerical examples and comparisonswith other schemes are presented. 展开更多
关键词 numerical solution fictitious domain method heat conduction EQUATION derivative BOUNDARY CONDITION
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On L ∞ Stability and Convergence of Fictitious Domain Method for the Numerical Solution to Parabolic Differential Equation with Derivative Boundary Conditions
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作者 孙志忠 《Journal of Southeast University(English Edition)》 EI CAS 1996年第2期108-111,共4页
This paper investigates some known difference schemes for the numerical solution to parabolic differential equation with derivative boundary conditions by the fictitious domain method.The stability and convergence in... This paper investigates some known difference schemes for the numerical solution to parabolic differential equation with derivative boundary conditions by the fictitious domain method.The stability and convergence in L ∞ are proven. 展开更多
关键词 numerical solution fictitious domain method PARABOLIC DIFFERENTIAL EQUATION derivative boundary condition
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Study on State of Terbium Ion in Liposome by One order Derivative Fluorescence Quenching Method
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作者 Mu Xiao-jing Fang Guo-chun Yao Song-nian 《Wuhan University Journal of Natural Sciences》 EI CAS 1999年第4期469-472,共4页
The state of Tb3+ is investigated in liposome. When the concentration of PC is below CMC (critical micell concentration), most of Tb3+ is associated with PC, the binding constant is about 3.35×103 L/mol. When the... The state of Tb3+ is investigated in liposome. When the concentration of PC is below CMC (critical micell concentration), most of Tb3+ is associated with PC, the binding constant is about 3.35×103 L/mol. When the concentration of PC is beyond CMC, most of Tb3+ is dimerized, the dimerization constant is about 3.92×104L/mol. In PC?CH?H2O system, the binding constant of Tb3+?CH complex 2.93×104L/mol is obtained. 展开更多
关键词 one-order derivative fluorescence quenching method LIPOSOME PC-Tb binding constant
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Determination of Fenofibrate and the Degradation Product Using Simultaneous UV-Derivative Spectrometric Method and HPLC
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作者 Fathy M. M. Salamaa Mohamed W. I. Nassar +2 位作者 Mohie M. K. Sharaf El-Din Khalid A. M. Attia Mohamed Yousri Kaddah 《American Journal of Analytical Chemistry》 2011年第3期332-343,共12页
Two new selective, precise, and accurate methods were developed for the determination of fenofibrate in the presence of its basic degradation product. In the first method fenofibrate was determined using an algorithm ... Two new selective, precise, and accurate methods were developed for the determination of fenofibrate in the presence of its basic degradation product. In the first method fenofibrate was determined using an algorithm bivariate calibration derivative method, in which an optimum pair of wavelengths was chosen for the determination of different binary mixtures. In the second method (HPLC), separation was achieved on RESTEK Pinnacle II phenyl column (5 μm, 250 × 4.6 mm) and Pinnacle II phenyl (5 μm, 10 × 4 mm) guard cartridge using a mobile phase consisting of methanol –0.1% phosphoric acid (60:40, v/v) at a flow rate 2 mL●min–1, and the column oven temperature was set at 50°C. The UV detector was time programmed at 302 nm and 289 nm for the internal standard (I.S.) and fenofibrate, respectively. The proposed methods were successfully applied for the determination of fenofibrate and its degradation product in the laboratory-prepared mixture and in pharmaceutical formulation. The assay results obtained using the bivariate method were statistically compared to those of the HPLC method and good agreement was observed. 展开更多
关键词 FENOFIBRATE Stability Degradation Product UV derivative Spectrometric method HPLC
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Shape Identification for Stokes-Oseen Problem Based on Domain Derivative Method
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作者 Wenjing Yan Jiangyong Hou 《Journal of Applied Mathematics and Physics》 2015年第12期1662-1670,共9页
In this paper, we consider the shape identification problem of a body immersed in the incompressible fluid governed by Stokes-Oseen equations. Based on the domain derivative method, we derive the explicit representati... In this paper, we consider the shape identification problem of a body immersed in the incompressible fluid governed by Stokes-Oseen equations. Based on the domain derivative method, we derive the explicit representation of the derivative of solution with respect to the boundary. Then, according to the boundary parametrization technique, we propose a regularized Gauss-Newton algorithm for the shape inverse problem. Finally, numerical examples indicate that the iterative algorithm is feasible and effective for the practical purpose. 展开更多
关键词 INVERSE Problem SHAPE Identification Stokes-Oseen EQUATIONS DOMAIN derivative method
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Film-Forming Properties of Fullerene Derivatives in Electrospray Deposition Method
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作者 Kazumasa Takeshi Kenji Takagi +2 位作者 Takeshi Fukuda Teiji Chihara Yusuke Tajima 《Journal of Surface Engineered Materials and Advanced Technology》 2013年第1期84-88,共5页
Thin films of three types of fullerene derivatives were prepared through the electrospray deposition (ESD) method. The optimized conditions for the fabrication of the thin films were investigated for different types o... Thin films of three types of fullerene derivatives were prepared through the electrospray deposition (ESD) method. The optimized conditions for the fabrication of the thin films were investigated for different types of fullerene derivatives: [6,6]-phenyl-C61-butyric acid methyl ester, [6,6]-phenyl-C71-butyric acid methyl ester, and indene-C60-monoadduct. The spray diameter during the ESD process was observed as a function of the supply rate achieved by changing the applied voltage. In all cases, the spray diameter increased with increasing applied voltage, reaching the maximum diameter (Dmax) in the voltage range 4 to 6 kV. It was clear that Dmax was influenced by the dipole moments of the fullerene derivatives (as calculated by density functional theory methods). Scanning electron microscopy observation of the?fabricated thin films showed that imbricated structures were formed through the stacking of the fullerene-derivative sheets. Atomic force microscopy images revealed that the density of the imbricated structure was dependent on the spray diameter during the ESD process, and the root-mean-square roughness of the film surface decreased with increasing applied voltage. These findings suggest that the ESD method will be effective for the preparation of fullerene-derivative thin films for the production of organic devices. 展开更多
关键词 ELECTROSPRAY Deposition method FULLERENE derivative Thin FILM Scanning Electron MICROSCOPE Imbricated Structure Atomic Force MICROSCOPE Root-Mean-Square ROUGHNESS
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Direct Perturbation Method for Derivative Nonlinear Schrdinger Equation
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作者 CHENG Xue-Ping LIN Ji HAN Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期501-504,共4页
We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbati... We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbation solutions are obtained. Based on these approximate solutions, the analytical forms of soliton parameters, such as the velocity, the width and the initial position, are carried out and the effects of perturbation on solitons are analyzed at the same time. A numerical simulation of perturbed DNLSE finally verifies the results of the perturbation method. 展开更多
关键词 direct perturbation method perturbed derivative nonlinear SchrSdinger equation
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Complex derivatives valuation: applying the Least-Squares Monte Carlo Simulation Method with several polynomial basis
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作者 Ursula Silveira Monteiro de Lima Carlos Patricio Samanez 《Financial Innovation》 2016年第1期1-14,共14页
Background:This article investigates the Least-Squares Monte Carlo Method by using different polynomial basis in American Asian Options pricing.The standard approach in the option pricing literature is to choose the b... Background:This article investigates the Least-Squares Monte Carlo Method by using different polynomial basis in American Asian Options pricing.The standard approach in the option pricing literature is to choose the basis arbitrarily.By comparing four different polynomial basis we show that the choice of basis interferes in the option's price.Methods:We assess Least-Squares Method performance in pricing four different American Asian Options by using four polynomial basis:Power,Laguerre,Legendre and Hermite A.To every American Asian Option priced,three sets of parameters are used in order to evaluate it properly.Results:We show that the choice of the basis interferes in the option's price by showing that one of them converges to the option's value faster than any other by using fewer simulated paths.In the case of an Amerasian call option,for example,we find that the preferable polynomial basis is Hermite A.For an Amerasian put option,the Power polynomial basis is recommended.Such empirical outcome is theoretically unpredictable,since in principle all basis can be indistinctly used when pricing the derivative.Conclusion:In this article The Least-Squares Monte Carlo Method performance is assessed in pricing four different types of American Asian Options by using four different polynomial basis through three different sets of parameters.Our results suggest that one polynomial basis is best suited to perform the method when pricing an American Asian option.Theoretically all basis can be indistinctly used when pricing the derivative.However,our results does not confirm these.We find that when pricing an American Asian put option,Power A is better than the other basis we have studied here whereas when pricing an American Asian call,Hermite A is better. 展开更多
关键词 Complex derivatives valuation Least-Squares Monte Carlo method Amerasian options Polynomial basis
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A CMOS 3.1 - 10.6 GHz UWB LNA Employing Modified Derivative Superposition Method
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作者 Amir Homaee 《Circuits and Systems》 2013年第3期323-327,共5页
Low noise amplifier (LNA) performs as the initial amplification block in the receive path in a radio frequency (RF) receiver. In this work an ultra-wideband 3.1 10.6-GHz LNA is discussed. By using the proposed circuit... Low noise amplifier (LNA) performs as the initial amplification block in the receive path in a radio frequency (RF) receiver. In this work an ultra-wideband 3.1 10.6-GHz LNA is discussed. By using the proposed circuits for RF CMOS LNA and design methodology, the noise from the device is decreased across the ultra wide band (UWB) band. The measured noise figure is 2.66 3 dB over 3.1 10.6-GHz, while the power gain is 14 ± 0.8 dB. It consumes 23.7 mW from a 1.8 V supply. The input and output return losses (S11 & S22) are less than –11 dB over the UWB band. By using the modified derivative superposition method, the third-order intercept point IIP3 is improved noticeably. The complete circuit is based on the 0.18 μm standard RFCMOS technology and simulated with Hspice simulator. 展开更多
关键词 Broadband LOW-NOISE Amplifier (LNA) Noise FIGURE ULTRA-WIDEBAND (UWB) MODIFIED derivative Su-perposition method
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A Concise Method for the Preparation of β-Hydroxymethyl α-Furfuryl Amine Derivative and its Application to Synthesis of 1-Deoxyazasugar Isomers
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期183-183,共1页
关键词 A Concise method for the Preparation of Furfuryl Amine derivative and its Application to Synthesis of 1-Deoxyazasugar Isomers
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DETERMINATION OF STABILITY CONSTANTS OF THE COORDINATION COMPOUNDS OF Au(Ⅲ)-2-MERCAPTOPYRIDINE-1-OXIDE AND METHYL DERIVATIVES——METHOD OF DUAL-WAVELENGTH CORRESPONDING SOLUTIONS
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作者 Yang CAO Bao Lin SONG Department of Chemistry,Xuzhou Teacher’s College,Xuzhou 221009Cheng ZENG Coordination Chemistry Institute,Nanjing University,Nanjing 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第1期59-62,共4页
In this paper,we report the deductive formula used for the method of dual-wavelength corresponding solutions under condition of having ligand interference and the stability constants of three new coordination compound... In this paper,we report the deductive formula used for the method of dual-wavelength corresponding solutions under condition of having ligand interference and the stability constants of three new coordination compounds [AuL_2]^+determined with this method.The stability of the three compounds,the necessity of controlling pH in experimental systems and the advantage of this method are discussed in detail. 展开更多
关键词 DETERMINATION OF STABILITY CONSTANTS OF THE COORDINATION COMPOUNDS OF Au MERCAPTOPYRIDINE-1-OXIDE AND METHYL derivativeS method OF DUAL-WAVELENGTH CORRESPONDING SOLUTIONS
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