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Molecular composition of water soluble fraction of petroleum products and crude oils:Insights into groundwater contamination potential and environmental forensics
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作者 Wang Yu Yuruo Wan +3 位作者 Wei Zhou Jiayi An Liting Tian Jie Ma 《Journal of Environmental Sciences》 2026年第1期437-444,共8页
Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.Th... Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.The aim of this study was to assess impact of 15 diverse oils on groundwater quality and environmental forensics based on oil-water equilibrium experiments.Our results indicate that contamination of groundwater by gasoline and naphtha is primarily attributed to volatile hydrocarbons,while pollution from diesel,kerosene,and crude oil is predominantly from non-hydrocarbons.Rapid determination of the extent of non-hydrocarbon pollution in WSFs was achieved through a new quantitative index.Gasoline and naphtha exhibited the highest groundwater contamination potential while kerosene and light crude oils were also likely to cause groundwater contamina-tion.Although volatile hydrocarbons in the WSFs of diesel and jet fuel do not easily exceed current regulatory standards,unregulated non-hydrocarbons may pose a more severe contamination risk to groundwater.Notably,the presence of significant benzene and toluene,hydrogenation and alkylation products(e.g.,C4-C5 alkylben-zenes,alkylindenes,alkyltetralins,and dihydro-indenes),cycloalkanes in WSFs can effectively be utilized for preliminary source identification of light distillates,middle distillates,and crude oils,respectively. 展开更多
关键词 Petroleum hydrocarbons Water soluble fraction Contaminated sites Groundwater contamination Source identification
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Bright and dark soliton solutions for some nonlinear fractional differential equations 被引量:6
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作者 Ozkan Guner Ahmet Bekir 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期52-59,共8页
In this work, we propose a new approach, namely ansatz method, for solving fractional differential equations based on a fractional complex transform and apply it to the nonlinear partial space-time fractional modified... In this work, we propose a new approach, namely ansatz method, for solving fractional differential equations based on a fractional complex transform and apply it to the nonlinear partial space-time fractional modified Benjamin-Bona- Mahoney (mBBM) equation, the time fractional mKdV equation and the nonlinear fractional Zoomeron equation which gives rise to some new exact solutions. The physical parameters in the soliton solutions: amplitude, inverse width, free parameters and velocity are obtained as functions of the dependent model coefficients. This method is suitable and more powerful for solving other kinds of nonlinear fractional PDEs arising in mathematical physics. Since the fractional deriva- tives are described in the modified Riemann-Liouville sense. 展开更多
关键词 exact solutions ansatz method space-time fractional modified Benjamin-Bona-Mahoney equa-tion time fractional mKdV equation
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Some Estimates for Commutators of Fractional Integrals Associated to Operators with Gaussian Kernel Bounds on Weighted Morrey Spaces 被引量:3
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作者 Hua Wang 《Analysis in Theory and Applications》 2013年第1期72-85,共14页
Let L be the infinitesimal generator of an analytic semigroup on L^2 (R^n) with Gaussian kernel bound, and let L^-α/2 be the fractional integrals of L for 0 〈 α 〈 n. In this paper, we will obtain some boundedn... Let L be the infinitesimal generator of an analytic semigroup on L^2 (R^n) with Gaussian kernel bound, and let L^-α/2 be the fractional integrals of L for 0 〈 α 〈 n. In this paper, we will obtain some boundedness properties of commutators [b, L^-α/2] on weighted Morrey spaces L^p,k(w) when the symbol b belongs to BMO(Rn) or the homogeneous Lipschitz space. 展开更多
关键词 Gaussian upper bound fractional integral weighted Morrey space commutator.
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Some It Formulas with Respect to Mixed Fractional Brownian Motion and Brownian Motion 被引量:2
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作者 舒慧生 阚秀 周海涛 《Journal of Donghua University(English Edition)》 EI CAS 2010年第4期530-534,共5页
Some It formulas with respect to mixed Fractional Brownian motion and Brownian motion were given in this paper.These extended the It formula for the fractional Wick It Skorohod integral with respect to Fractiona... Some It formulas with respect to mixed Fractional Brownian motion and Brownian motion were given in this paper.These extended the It formula for the fractional Wick It Skorohod integral with respect to Fractional Brownian motion,meanwhile extended the It formula for It Skorohod integral with respect to Brownian motion.Taylor's formula is applied to prove our conclusion in this article. 展开更多
关键词 fractional Brownian motion Brownian motion Itö formula
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ON SOME BOUNDARY VALUE PROBLEMS FOR NONHOMOGENOUS POLYHARMONIC EQUATION WITH BOUNDARY OPERATORS OF FRACTIONAL ORDER 被引量:1
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作者 Batirkhan TURMETOV 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期831-846,共16页
In the paper we study questions about solvability of some boundary value prob- lems for a non-homogenous poly-harmonic equation. As a boundary operator we consider differentiation operator of fractional order in Mille... In the paper we study questions about solvability of some boundary value prob- lems for a non-homogenous poly-harmonic equation. As a boundary operator we consider differentiation operator of fractional order in Miller-Ross sense. The considered problem is a generalization of well-known Dirichlet and Neumann problems. 展开更多
关键词 polyharmonic equation boundary value problem Dirichlet problem Neumann problem fractional derivative Miller-Ross operator
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The Exp-function Method for Some Time-fractional Differential Equations 被引量:1
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作者 Ahmet Bekir Ozkan Guner Adem Cevikel 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期315-321,共7页
In this article, the fractional derivatives in the sense of modified Riemann-Liouville derivative and the Exp-function method are employed for constructing the exact solutions of nonlinear time fractional partial diff... In this article, the fractional derivatives in the sense of modified Riemann-Liouville derivative and the Exp-function method are employed for constructing the exact solutions of nonlinear time fractional partial differential equations in mathematical physics. As a result, some new exact solutions for them are successfully established. It is indicated that the solutions obtained by the Exp-function method are reliable, straightforward and effective method for strongly nonlinear fractional partial equations with modified Riemann-Liouville derivative by Jumarie's. This approach can also be applied to other nonlinear time and space fractional differential equations. 展开更多
关键词 Exact solution exp-function method fractional differential equation
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Some Numerical Extrapolation Methods for the Fractional Sub-diffusion Equation and Fractional Wave Equation Based on the L1 Formula 被引量:1
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作者 Ren-jun Qi Zhi-zhong Sun 《Communications on Applied Mathematics and Computation》 2022年第4期1313-1350,共38页
With the help of the asymptotic expansion for the classic Li formula and based on the L1-type compact difference scheme,we propose a temporal Richardson extrapolation method for the fractional sub-diffusion equation.T... With the help of the asymptotic expansion for the classic Li formula and based on the L1-type compact difference scheme,we propose a temporal Richardson extrapolation method for the fractional sub-diffusion equation.Three extrapolation formulas are presented,whose temporal convergence orders in L_(∞)-norm are proved to be 2,3-α,and 4-2α,respectively,where 0<α<1.Similarly,by the method of order reduction,an extrapola-tion method is constructed for the fractional wave equation including two extrapolation formulas,which achieve temporal 4-γ and 6-2γ order in L_(∞)-norm,respectively,where1<γ<2.Combining the derived extrapolation methods with the fast algorithm for Caputo fractional derivative based on the sum-of-exponential approximation,the fast extrapolation methods are obtained which reduce the computational complexity significantly while keep-ing the accuracy.Several numerical experiments confirm the theoretical results. 展开更多
关键词 L1 formula Asymptotic expansion fractional sub-diffusion equation fractional wave equation Richardson extrapolation Fast algorithm
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On Some Modified Methods on Fractional Delay and Nonlinear IntegroDifferential Equation 被引量:1
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作者 A.A.Soliman K.R.Raslan A.M.Abdallah 《Sound & Vibration》 EI 2021年第4期263-279,共17页
The fundamental objective of this work is to construct a comparative study of some modified methods with Sumudu transform on fractional delay integro-differential equation.The existed solution of the equation is very ... The fundamental objective of this work is to construct a comparative study of some modified methods with Sumudu transform on fractional delay integro-differential equation.The existed solution of the equation is very accurately computed.The aforesaid methods are presented with an illustrative example. 展开更多
关键词 CONVERGENCE STABILITY fractional integro-differential equation
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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw 被引量:2
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作者 Meng-Ying Liu Zhe-Hui Zhang +7 位作者 Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi Yuan 《Green Energy & Environment》 SCIE EI CAS 2025年第1期161-172,共12页
Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin f... Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%. 展开更多
关键词 Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural
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The Fractional Investigation of Some Nonlinear Partial Differential Equations by Using an Efficient Procedure
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作者 Fairouz Tchier Hassan Khan +2 位作者 Shahbaz Khan Poom Kumam Ioannis Dassios 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2137-2153,共17页
The nonlinearity inmany problems occurs because of the complexity of the given physical phenomena.The present paper investigates the non-linear fractional partial differential equations’solutions using the Caputo ope... The nonlinearity inmany problems occurs because of the complexity of the given physical phenomena.The present paper investigates the non-linear fractional partial differential equations’solutions using the Caputo operator with Laplace residual power seriesmethod.It is found that the present technique has a direct and simple implementation to solve the targeted problems.The comparison of the obtained solutions has been done with actual solutions to the problems.The fractional-order solutions are presented and considered to be the focal point of this research article.The results of the proposed technique are highly accurate and provide useful information about the actual dynamics of each problem.Because of the simple implementation,the present technique can be extended to solve other important fractional order problems. 展开更多
关键词 fractional calculus laplace transform laplace residual power series method fractional partial differential equation power series fractional power series
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Bounds on Fractional Domination of Some Products of Graphs
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作者 陈学刚 孙良 邢化明 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期90-93,共4页
Let γ f(G) and γ~t f(G) be the fractional domination number and fractional total domination number of a graph G respectively. Hare and Stewart gave some exact fractional domination number of P n... Let γ f(G) and γ~t f(G) be the fractional domination number and fractional total domination number of a graph G respectively. Hare and Stewart gave some exact fractional domination number of P n×P m (grid graph) with small n and m . But for large n and m , it is difficult to decide the exact fractional domination number. Motivated by this, nearly sharp upper and lower bounds are given to the fractional domination number of grid graphs. Furthermore, upper and lower bounds on the fractional total domination number of strong direct product of graphs are given. 展开更多
关键词 fractional domination number fractional total domination number grid graph strong direct product
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SOME PROPERTIES FOR TWO-PARAMETER FRACTIONAL LEVY-WIENER PROCESS
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作者 Zhang RongmaoDept.of Math.,Zhejiang Univ.,Hangzhou 310028,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期115-124,共10页
In this paper,the properties about how small are the increments of the fractional Levy-Wiener process are studied,and some interesting results are obtained,which extend the result of Lin and Choi in 2001.
关键词 Sincrement inferior limit fractional Levy -Wiener processn
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NONEXISTENCE AND SYMMETRY OF SOLUTIONS TO SOME FRACTIONAL LAPLACIAN EQUATIONS IN THE UPPER HALF SPACE
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作者 郭艳艳 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期836-851,共16页
In this article, we consider the fractional Laplacian equation {(-△)α/2u=k(x)f(u),x∈Rn+, u=0, x Rn+, where 0 〈α 〈 2,En+:= {x = (x1,x2,… ,xn)|xn〉 0}. When K is strictly decreasing with respect to ... In this article, we consider the fractional Laplacian equation {(-△)α/2u=k(x)f(u),x∈Rn+, u=0, x Rn+, where 0 〈α 〈 2,En+:= {x = (x1,x2,… ,xn)|xn〉 0}. When K is strictly decreasing with respect to |x'|, the symmetry of positive solutions is proved, where x' = (x1, x2,…, xn-1) ∈Rn- 1. When K is strictly increasing with respect to xn or only depend on xn, the nonexistence of positive solutions is obtained. 展开更多
关键词 fractional Laplacian method of moving planes radial symmetry NONEXISTENCE
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Boundedness of Fractional Maximal Operators on Some of Homogeneous Groups
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作者 王杰 陈丙康 张建林 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期449-453,共5页
Let M α be the fractional maximal operators (0<α≤1) and (u,v) a pair of weight functions, u∈D ∞, σ=v~~~~^(-1/(p-1))∈A ∞. The boundedness of M α on some homogenous groups (G, ‖·‖, dx) and the cov... Let M α be the fractional maximal operators (0<α≤1) and (u,v) a pair of weight functions, u∈D ∞, σ=v~~~~^(-1/(p-1))∈A ∞. The boundedness of M α on some homogenous groups (G, ‖·‖, dx) and the covering Lemma of Calderon-Zygmund type are studied. Not only an adequate covering Lemma of Calderon-Zygmund type is shown, but also the boundedness of fractional maximal operators M α(0<α≤1) on some of homogeneous groups with respect to a given pair of weight functions (u,v) as above is proved. Moreover, a sufficient and necessary condition for M α∈B(u^qdx, v~~pdx), 0<α<1, 1<p<1α, and 1q=1p-α is also given. Finally, an application of the results is also obtained. 展开更多
关键词 BOUNDEDNESS fractional maximal operator homogeneous groups weight functions
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Some limit results on supremum of Shepp statistics for fractional Brownian motion
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作者 TAN Zhong-quan CHEN Yang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第3期269-282,共14页
Define the incremental fractional Brownian field ZH(τ, s) = BH(s+τ) -BH(s),where BH(s) is a standard fractional Brownian motion with Hurst parameter H ∈ (0, 1). Inthis paper, we first derive an exact asy... Define the incremental fractional Brownian field ZH(τ, s) = BH(s+τ) -BH(s),where BH(s) is a standard fractional Brownian motion with Hurst parameter H ∈ (0, 1). Inthis paper, we first derive an exact asymptotic of distribution of the maximum MH(Tu) =supτ∈[0,1],s∈[0,xτu] ZH(τ, s), which holds uniformly for x ∈ [A, B] with A, B two positive con-stants. We apply the findings to analyse the tail asymptotic and limit theorem of MH (τ) witha random index τ. In the end, we also prove an almost sure limit theorem for the maximum M1/2(τ) with non-random index T. 展开更多
关键词 EXTREMES Shepp statistics fractional Brownian motion exact asymptotic almost sure limit theorem
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Some space-time fractional bright–dark solitons and propagation manipulations for a fractional Gross–Pitaevskii equation with an external potential
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作者 Li Li Fajun Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第7期86-94,共9页
Some nonautonomous bright–dark solitons(NBDSs)and nonautonomous controllable behaviors in the conformable space-time fractional Gross–Pitaevskii(FGP)equation with some external potentials are derived.We consider the... Some nonautonomous bright–dark solitons(NBDSs)and nonautonomous controllable behaviors in the conformable space-time fractional Gross–Pitaevskii(FGP)equation with some external potentials are derived.We consider the relations between the space-time FGP equation and the fractional nonlinear Schr?dinger equation and analyze the properties of the obtained equation with group velocity dispersion and spatiotemporal dispersion.Then,some constraint conditions of the valid soliton solutions are given.Furthermore,we consider the effect ofαandβin NBDSs of the space-time FGP equation.Some fractional spatial–temporal controlling wave prolong phenomena are considered,and some different propagation dynamics are generated via the different parametersαandβ.We study novel shape bright soliton solution,novel‘h’-shape dark soliton and some interactions of nonautonomous bright–dark solitons.The reported results of some novel interactions are considered,which can explain some models of the electrical and optical fields. 展开更多
关键词 nonautonomous fractional soliton soliton interaction space-time fractional Gross-Pitaevskii equation
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THE RELATIONSHIP BETWEEN RADIATION DOSE AND CHROMOSOME ABERRATIONS AND MICRONUCLEI IN RABBITS EXPOSED TO FRACTIONATED WHOLE-BODY ^(60)Co GAMMA RAYS
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《癌变·畸变·突变》 CAS CSCD 1991年第S1期4-4,共1页
The frequencies of chromosome aberrationsand micronuclei showed an increase withdoses after irradiation of rabbitsexposed to fractionated or single whole-body <sup>60</sup>Co gamma rays.At most dose points,
关键词 fractionated GAMMA chromosome irradiation CO GAMMA RAYS GAMMA ABERRATION body quadratic doses
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Exactly solving some typical Riemann-Liouville fractional models by a general method of separation of variables
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作者 Cheng-Shi Liu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第5期46-51,共6页
Finding exact solutions for Riemann–Liouville(RL)fractional equations is very difficult.We propose a general method of separation of variables to study the problem.We obtain several general results and,as application... Finding exact solutions for Riemann–Liouville(RL)fractional equations is very difficult.We propose a general method of separation of variables to study the problem.We obtain several general results and,as applications,we give nontrivial exact solutions for some typical RL fractional equations such as the fractional Kadomtsev–Petviashvili equation and the fractional Langmuir chain equation.In particular,we obtain non-power functions solutions for a kind of RL time-fractional reaction–diffusion equation.In addition,we find that the separation of variables method is more suited to deal with high-dimensional nonlinear RL fractional equations because we have more freedom to choose undetermined functions. 展开更多
关键词 Riemann–Liouville derivative exact solution fractional differential equation separation of variables method
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Some New Delay Integral Inequalities Based on Modified Riemann-Liouville Fractional Derivative and Their Applications
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作者 Zhimin Zhao Run Xu 《Journal of Applied Mathematics and Physics》 2015年第5期465-477,共13页
By using the properties of modified Riemann-Liouville fractional derivative, some new delay integral inequalities have been studied. First, we offered explicit bounds for the unknown functions, then we applied the res... By using the properties of modified Riemann-Liouville fractional derivative, some new delay integral inequalities have been studied. First, we offered explicit bounds for the unknown functions, then we applied the results to the research concerning the boundness, uniqueness and continuous dependence on the initial for solutions to certain fractional differential equations. 展开更多
关键词 MODIFIED Riemann-Liouville fractionAL DERIVATIVE INTEGRAL INEQUALITIES DELAY fractionAL Differential Equation
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Existence and Continuous Dependence of Mild Solutions for Some Fractional Neutral Differential Equations with Nonlocal Initial Conditions
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作者 叶海平 刘姣 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期609-615,共7页
The existence,uniqueness,and continuous dependence to the mild solutions of the nonlocal Cauchy problem were proved for a class of semilinear fractional neutral differential equations.The results are obtained by using... The existence,uniqueness,and continuous dependence to the mild solutions of the nonlocal Cauchy problem were proved for a class of semilinear fractional neutral differential equations.The results are obtained by using the Krasnoselskii's fixed point theorem and the theory of resolvent operators for integral equations. 展开更多
关键词 fractional differential equation nonlocal initial condition mild solution Krasnoselskii’s fixed point theorem resolvent operator
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