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Extraction,Utilization,Functional Modification,and Application of Cellulose and Its Derivatives
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作者 Wohua He Fangji Wu Haoqun Hong 《Journal of Renewable Materials》 2025年第9期1707-1763,共57页
Under the background of the current energy crisis and environmental pollution,the development of green and sustainable materials has become particularly urgent.As one of the most abundant natural polymers on earth,cel... Under the background of the current energy crisis and environmental pollution,the development of green and sustainable materials has become particularly urgent.As one of the most abundant natural polymers on earth,cellulose has attracted wide attention due to its green recycling,sustainable development,degradability,and low cost.Therefore,cellulose and its derivatives were used as the starting point for comprehensive analysis.First,the basic structural properties of cellulose were discussed,and then the extraction and utilization methods of cellulose were reviewed,including Sodium Hydroxide based solvent system,N,N-Dimethylacetamide/Lithium Chloride System,N-Methylmorpholine-N-Oxide(NMMO)system,ionic liquids(ILs)system,and deep eutectic solvent(DES)system.Then,the functional modification techniques of cellulose are introduced,including nano-modification,small molecule modification,and macromolecular modification.Finally,the potential applications of cellulose in the fields of reinforcement materials,self-healing materials,radioactive cooling,nanogenerators,and biomedicine were discussed.At the end of this paper,the challenges and future development direction of cellulose materials are prospectively analyzed,aiming at providing guidance and inspiration for the research and application in related fields. 展开更多
关键词 Cellulose and derivatives extraction and utilization functional modification APPLICATIONS
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FUNCTIONAL INEQUALITIES, ISOMORPHISMS AND DERIVATIONS ON BANACH ALGEBRAS
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作者 Hamid KHODAEI 《Acta Mathematica Scientia》 2025年第3期855-866,共12页
We analyze existence and uniqueness of solutions for perturbations of a Jensen functional inequality in several variables.Applications in connection with asymptotic behaviors of isomorphisms,derivations and n-Jordan d... We analyze existence and uniqueness of solutions for perturbations of a Jensen functional inequality in several variables.Applications in connection with asymptotic behaviors of isomorphisms,derivations and n-Jordan derivations on Banach algebras are also provided.The results of this paper correct and improve the main results of[12,16,22,23]and improve the corresponding results in[2,9,27],but under weaker assumptions. 展开更多
关键词 functional inequality ISOMORPHISM derivATION n-Jordan derivation
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Epidemiological Modeling of Pneumococcal Pneumonia:Insights from ABC Fractal-Fractional Derivatives
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作者 Mohammed Althubyani Nidal E.Taha +2 位作者 Khdija O.Taha Rasmiyah A.Alharb Sayed Saber 《Computer Modeling in Engineering & Sciences》 2025年第6期3491-3521,共31页
This study investigates the dynamics of pneumococcal pneumonia using a novel fractal-fractional Susceptible-Carrier-Infected-Recovered model formulated with the Atangana-Baleanu in Caputo(ABC)sense.Unlike traditional ... This study investigates the dynamics of pneumococcal pneumonia using a novel fractal-fractional Susceptible-Carrier-Infected-Recovered model formulated with the Atangana-Baleanu in Caputo(ABC)sense.Unlike traditional epidemiological models that rely on classical or Caputo fractional derivatives,the proposed model incorporates nonlocal memory effects,hereditary properties,and complex transmission dynamics through fractalfractional calculus.The Atangana-Baleanu operator,with its non-singular Mittag-Leffler kernel,ensures a more realistic representation of disease progression compared to classical integer-order models and singular kernel-based fractional models.The study establishes the existence and uniqueness of the proposed system and conducts a comprehensive stability analysis,including local and global stability.Furthermore,numerical simulations illustrate the effectiveness of the ABC operator in capturing long-memory effects and nonlocal interactions in disease transmission.The results provide valuable insights into public health interventions,particularly in optimizing vaccination strategies,treatment approaches,and mitigation measures.By extending epidemiological modeling through fractal-fractional derivatives,this study offers an advanced framework for analyzing infectious disease dynamics with enhanced accuracy and predictive capabilities. 展开更多
关键词 Fractional derivatives nonlinear equations simulation numerical results iterative method time varying control system lyapunov functions
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Approximate Controllability of Neutral Partial Differential System with Hilfer Fractional Derivative and not Instantaneous Impulses Effects
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作者 Bo ZHU Baoyan HAN 《Journal of Mathematical Research with Applications》 2025年第5期637-648,共12页
In this article,we study the approximate controllability of neutral partial differential equations with Hilfer fractional derivative and not instantaneous impulses effects.By using the Sadovskii's fixed point theo... In this article,we study the approximate controllability of neutral partial differential equations with Hilfer fractional derivative and not instantaneous impulses effects.By using the Sadovskii's fixed point theorem,fractional calculus and resolvent operator functions,we prove the approximate controllability of the considered system. 展开更多
关键词 approximate controllability Hilfer fractional derivative not instantaneous impulses resolvent operator functions
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Two new amino acid derivatives as green corrosion inhibitors against Q235 steel in HCl solution:Experimental and theoretical investigations
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作者 Chaoyi Li Minghao Su +7 位作者 Tianyi Hou Yuhe Shi Junrong Huang Jing Qing Wenxin Niu Yinghe Zhang Ling Zhang Hengzhi You 《International Journal of Minerals,Metallurgy and Materials》 2025年第7期1617-1627,共11页
Amino acids have emerged as promising green alternatives to replace toxic inhibitors in corrosion protection applications.In this study,we present a one-step synthetic approach to get 4-(tert-butyl)benzoyl)methionine(... Amino acids have emerged as promising green alternatives to replace toxic inhibitors in corrosion protection applications.In this study,we present a one-step synthetic approach to get 4-(tert-butyl)benzoyl)methionine(P-Meth)and 4-(tert-butyl)benzoyl)cysteine(P-Cys)through the acylation reactions between methionine or cysteine and p-tert-butylbenzoic acid,respectively,which exhibit a super protective performance toward metals against corrosion.The corrosion rates of Q235 steel in 1 M HCl were reduced from 4.542 to 0.202and 0.312 mg·h^(-1)·cm^(-2)in the presence of 100 mg·L^(-1)P-Meth and P-Cys,respectively.The surface structures of Q235 steel remained unbroken after 12 h in 1 M HCl medium.The charge transfer resistances of corrosion reactions were enhanced by 12 and 9 times in the presence of P-Meth and P-Cys,respectively.P-Meth and P-Cys were adsorbed onto the Q235 steel via chemical actions,which were accompanied by minimal physical action.Molecular dynamic simulations demonstrate the higher binding energy of P-Meth onto Q235 steel than P-Cys.The study contributes to the corrosion protection of metals with green and environmentally friendly methods. 展开更多
关键词 amino acid derivatives anti-corrosion reagents green chemistry Q235 steel density functional theory
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Avoiding the Use of Lagrange Multipliers. II. Constrained Extrema of Functionals and the Evaluation of Constrained Derivatives
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作者 David S. Corti Ricardo Fariello 《Journal of Applied Mathematics and Physics》 2024年第8期2764-2788,共25页
A method for determining the extrema of a real-valued and differentiable function for which its dependent variables are subject to constraints and that avoided the use of Lagrange multipliers was previously presented ... A method for determining the extrema of a real-valued and differentiable function for which its dependent variables are subject to constraints and that avoided the use of Lagrange multipliers was previously presented (Corti and Fariello, Op. Res. Forum 2 (2021) 59). The method made use of projection matrices, and a corresponding Gram-Schmidt orthogonalization process, to identify the constrained extrema. Furthermore, information about the second-derivatives of the given function with constraints was generated, from which the nature of the constrained extrema could be determined, again without knowledge of the Lagrange multipliers. Here, the method is extended to the case of functional derivatives with constraints. In addition, constrained first-order and second-order derivatives of the function are generated, in which the derivatives with respect to a given variable are obtained and, concomitantly, the effect of the variations of the remaining chosen set of dependent variables are strictly accounted for. These constrained derivatives are valid not only at the extrema points, and also provide another equivalent route for the determination of the constrained extrema and their nature. 展开更多
关键词 Constrained Extrema functional derivatives Projection Matrices
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Covalent functionalization of graphene oxide by 9-(4-aminophenyl)acridine and its derivatives 被引量:5
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作者 Yi Si Feng Jing Jing Ma +4 位作者 Xin Yan Lin Jia Song Zhang Peng Lv Hua Jian Xu Lin Bao Luo 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第12期1411-1414,共4页
Graphene/acridine (G-Acr) hybrid structures were synthesized through covalent functionalization of graphene oxide with 9-(4- aminophenyl)acridine (APA) and its derivatives. The G-Act hybrids were characterized b... Graphene/acridine (G-Acr) hybrid structures were synthesized through covalent functionalization of graphene oxide with 9-(4- aminophenyl)acridine (APA) and its derivatives. The G-Act hybrids were characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry, thermal gravimetric analysis and Raman spectroscopy. X-ray photoelectron spectroscopy confirms that the binding energies of APA and its derivatives shifted to higher values, revealing pronounced charge transfer at the interface of graphene and organic molecules. 展开更多
关键词 Graphene oxide Covalent functionalization Hybrid material Acridine derivative
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HIGHER RADIAL DERIVATIVE OF BLOCH TYPE FUNCTIONS 被引量:4
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作者 李波 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期433-445,共13页
In this paper, The integral characterizations of alpha-Bloch (little alpha-Bloch) axe given in terms of higher radial derivative, and their characterizations of Caxleson type measure are obtained.
关键词 Bloch type function higher radial derivative Carleson type measure
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Integral Inequalities of Hermite-Hadamard Type for Functions Whose 3rd Derivatives Are <i>s</i>-Convex 被引量:4
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作者 Ling Chun Feng Qi 《Applied Mathematics》 2012年第11期1680-1685,共6页
In the paper, the authors find some new inequalities of Hermite-Hadamard type for functions whose third derivatives are s-convex and apply these inequalities to discover inequalities for special means.
关键词 INTEGRAL INEQUALITY Hermite-Hadamard’s INTEGRAL INEQUALITY s-Convex function derivative Mean
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High-Order Radial Derivatives of Harmonic Function and Gravity Anomaly 被引量:8
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作者 Ziqing Wei 《Journal of Physical Science and Application》 2014年第7期454-467,共14页
The first through ninth radial derivatives of a harmonic function and gravity anomaly are derived in this paper. These derivatives can be used in the analytical continuation application. For the downward continuation ... The first through ninth radial derivatives of a harmonic function and gravity anomaly are derived in this paper. These derivatives can be used in the analytical continuation application. For the downward continuation of gravity anomaly, the Taylor series approach developed in the paper is equivalent theoretically to but more efficient and storage-saving computationally than the well-known gradient operator approach. Numerical simulation shows that Taylor series expansion constructed by the derived formulas for the radial derivatives of gravity disturbance is still convergent for height up to 4 km. 展开更多
关键词 Harmonic function gravity anomaly gravity disturbance high-order radial derivative analytical continuation.
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On the Variational Problems of the Functionals with Derivatives of Higher Orders and Undetermined Boundary 被引量:1
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作者 老大中 谈天民 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期116-121,共6页
According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of va... According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of variations are researched, the functionals depend on single argument, arbitrary unknown functions and their derivatives of higher orders. A new view point is posed and demonstrated, i.e. when the first variation of the functional is equal to zero, all the variational terms are not independent to each other, and at least one of them is equal to zero. Some theorems and corollaries of the variational problems of the functionals are obtained. 展开更多
关键词 calculus of variations functionAL variational problems derivatives of higher orders undetermined boundary
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A New Definition for Generalized First Derivative of Nonsmooth Functions 被引量:1
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作者 Ali Vahidian Kamyad Mohammad Hadi Noori Skandari Hamid Reza Erfanian 《Applied Mathematics》 2011年第10期1252-1257,共6页
In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are ap... In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are applied for non-smooth functions which by solving these problems we obtain a kind of generalized first derivatives. For this purpose, a linear programming problem corresponding functional optimization problem is obtained which their optimal solutions give the approximate generalized first derivative. We show the efficiency of our approach by obtaining derivative and generalized derivative of some smooth and nonsmooth functions respectively in some illustrative examples. 展开更多
关键词 Generalized derivative SMOOTH and NONSMOOTH functionS FOURIER analysis Linear PROGRAMMING functional Optimization
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Some Inequalities of Hermite-Hadamard Type for Functions Whose 3rd Derivatives Are <i>P</i>-Convex 被引量:1
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作者 Boyan Xi Shuhong Wang Feng Qi 《Applied Mathematics》 2012年第12期1898-1902,共5页
In the paper, the authors establish some new Hermite-Hadamard type inequalities for functions whose 3rd derivatives are P-convex.
关键词 INTEGRAL INEQUALITY Hermite-Hadamard’s INTEGRAL INEQUALITY P-Convex function derivative
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The Normal Meromorphic Functions Family Concerning Higher Order Derivative and Shared Set by One-Way 被引量:1
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作者 Yi Li 《Advances in Pure Mathematics》 2011年第6期322-324,共3页
Let F be a meromorphic functions family on the unit disc Δ, If for every (the zeros of f is a multiplicity of at least k) and if then and ( ), then F is normal on Δ.
关键词 MEROMORPHIC function NORMALITY Criterion SHARED Set by One-Way Higher Order derivative
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The Higher Derivatives of Bianalytic Functions 被引量:1
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作者 谢春平 刘涛 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第3期59-62, ,共4页
By using the Cauchy integral formula of bianalytic functions, the formula of higher derivatives of bianalytic functions and Weierstrass Theorem are obtained.
关键词 bianalytic function higher derivative Weierstrass Theorem
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HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION FUNCTIONS AND THEIR LOGICAL DERIVATIVES 被引量:1
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作者 Sha Zhen Chen Gang Zhejiang University,China 《Analysis in Theory and Applications》 1993年第4期73-88,共16页
In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their... In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their logical derivatives of order α. 展开更多
关键词 HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION functionS AND THEIR LOGICAL derivativeS der HAAR FIF
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SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS 被引量:1
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作者 T.F.Xie S.P.Zhou 《Analysis in Theory and Applications》 1994年第4期100-109,共10页
This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of... This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of deereeon the nodes X_nUY_n(see the definition of the next). 展开更多
关键词 SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE function AND ITS derivativeS BY LAGRANGE INTERPOLATING POLYNOMIALS APPI ZR
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ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY HERMITE INTERPOLATION 被引量:1
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作者 Tingfan Xie Ziyu Wang China Institute of Metrology, China Henan University, China 《Analysis in Theory and Applications》 1994年第3期45-55,共11页
The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen-... The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen- eral. 展开更多
关键词 MATH ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF functionS AND THEIR derivativeS BY HERMITE INTERPOLATION 石瓦
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The derivative-dependent functional variable separation for the evolution equations 被引量:3
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作者 张顺利 楼森岳 屈长征 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2765-2776,共12页
This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which adm... This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which admits the derivative- dependent functional separable solutions (DDFSSs). We also extend the concept of the DDFSS to cover other variable separation approaches. 展开更多
关键词 derivative-dependent functional variable separation evolution equations generalized conditional symmetry
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Basis-free expressions for derivatives of a subclass of nonsymmetric isotropic tensor functions
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作者 王志乔 兑关锁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第9期1249-1257,共9页
The present paper generalizes the method for solving the derivatives of symmetric isotropic tensor-valued functions proposed by Dui and Chen (2004) to a subclass of nonsymmetric tensor functions satisfying the commu... The present paper generalizes the method for solving the derivatives of symmetric isotropic tensor-valued functions proposed by Dui and Chen (2004) to a subclass of nonsymmetric tensor functions satisfying the commutative condition. This subclass of tensor functions is more general than those investigated by the existing methods. In the case of three distinct eigenvalues, the commutativity makes it possible to introduce two scalar functions, which will be used to construct the general nonsymmetric tensor functions and their derivatives. In the cases of repeated eigenvalues, the results are acquired by taking limits. 展开更多
关键词 nonsymmetric tensor derivative of tensor function scalar function fourthorder tensor
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