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Engineering（科研） 2011年第1期3卷 73-82页

作者： Zakir M.O.Rzayev burcu senol Ernur A.Soylemez Department of Chemical Engineering Faculty of EngineeringDivision of Nanoscience&Nanomedicine Hacettepe UniversityAnkaraTurkey

Functional copolymer–clay hybrids were synthesized by radical-initiated intercalative copolymerization of maleic acid (MA) and acrylamide (AAm) with 2,2’-azobis (2-methylpropionamidine) dihydrochloride as a water-soluble ionizable radical initiator in the presence of reactive (octadecyl amine (ODA)-MMT) and non-reactive (dimethyldodecyl ammonium (DMDA)-MMT) organoclays at 50oC in aqueous medium under nitrogen atmosphere. The monomers was dissolved in aqueous medium, as well as both used clay particles were easily dissolved and dispersed with partially swollen in deionized water, respectively. Structure, thermal behavior and morphology of the synthesized nanocomposites were investigated by FTIR, XRD, DSC-TGA, SEM and TEM analysis methods, respectively. It was demonstrated that intercalative copolymerization proceed via ion exchange between organoclays and carboxylic groups of monomers/polymers which essentially improved interfacial interaction of polymer matrix and clay layers through strong H-bonding. In case of intercalative copolymerization in the presence of ODA-MMT clay, similar improvement was provided by in situ hydrogen-bonding and amidolysis of carboxylic/anhydride groups from copolymer chains with primary amine group of ODA-MMT. The nanocomposites exhibit higher intercalation/exfoliation degree of copolymer chains, improved thermal properties and fine dispersed morphology.

关键词： Functional Copolymer Organoclays Nanohybrid Composites Thermal Behavior Morphology

New solutions for four novel generalized nonlinear fractional fifth-order equations

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Journal of Ocean Engineering and Science 2024年第1期9卷 59-65页

作者： Mehmet senol Lanre Akinyemi Henrietta Nkansah Waleed Adel Nevsehir HacıBekta¸s Veli University Department of MathematicsNevsehirTurkey Department of Mathematics Lafayette CollegeEastonPennsylvaniaUSA Department of Mathematics University of Cape CoastCape CoastGhana Department of Mathematics and Engineering Physics Faculty of EngineeringMansoura UniversityEgypt UniversitéFrançaise dÉgypte Ismailia Desert RoadEl ShoroukCairoEgypt

In this paper,new four fifth-order fractional nonlinear equations are derived and *** frac-tional terms are defined in the conformable sense and these equations are then solved using two effective methods,namely,the sub-equation and the generalized Kudryashov *** methods were tested on the proposed models and succeeded in finding new solutions with different values of parameters.A graphical representation of some results is provided and proves the efficiency and applicability of the proposed methods for providing solutions with known physical *** methods are good candi-dates for solving other similar problems in the future.

关键词： Conformable derivative Generalized Kudryashov method Sub-equation method Riccati equation Solitons

Qualitative behavior of discrete-time Caputo-Fabrizio logistic model with Allee effect

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International Journal of Biomathematics 2024年第4期17卷 217-234页

作者： Hatice Karakaya senol Kartal ilhan Oztirk Department of Mathematics Faculty of Science Erciyes UniversityKayseriTurkey Department of Science and Mathematics Education Faculty of Education Nevsehir Haci Bektas Veli University NevsehirTurkey Kapadokya University NevsehirTurkey

The aim of this paper is to investigate the dynamic behaviors of fractional-order logistic model with Allee effects in Caputo-Fabrizio *** of all,we apply the two-step Adams-Bashforth scheme to discretize the fractional-order logistic differential equation and obtain the two-dimensional discrete *** parametric conditions for local asymptotic stability of equilibrium points are obtained by Schur-Chon ***,we discuss the existence and direction for Neimark-Sacker bifurcations with the help of center manifold theorem and bifurcation *** simulations are provided to illustrate theoretical *** is observed that Allee effect plays an important role in stability *** Allee effect in population enhances the stability of the coexisting steady *** additional,the effect of fractional-order derivative on dynamic behavior of the system is also investigated.

关键词： Caputo-Fabrizio fractional derivative two-step Adams-Basforth method logistic differential equation Neimark-Sacker bifurcation Allee effect

A novel approach to study generalized coupled cubic Schrödinger-Korteweg-de Vries equations

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Journal of Ocean Engineering and Science 2024年第1期9卷 13-24页

作者： Lanre Akinyemi P.Veeresha M.T.Darvishi Hadi Rezazadeh Mehmet senol Udoh Akpan Department of Mathematics Lafayette CollegeEastonPAUSA Department of Mathematics Christ Deemed to be UniversityBengaluru 560029India Department of Mathematics Razi UniversityKermanshah 67149Iran Faculty of Engineering Technology Amol University of Special Modern TechnologiesAmolIran Department of Mathematics Nev¸s ehir HacıBekta¸s Veli UniversityNev¸s ehirTurkey Drexel University Department of MathematicsPhiladelphiaPAUSA

The Kortewegde Vries(KdV)equation represents the propagation of long waves in dispersive media,whereas the cubic nonlinear Schrödinger(CNLS)equation depicts the dynamics of narrow-bandwidth wave packets consisting of short dispersive waves.A model that couples these two equations seems in-triguing for simulating the interaction of long and short waves,which is important in many domains of applied sciences and engineering,and such a system has been investigated in recent *** work uses a modified Sardar sub-equation procedure to secure the soliton-type solutions of the generalized cubic nonlinear Schrödinger-Korteweg-de Vries system of *** various selections of arbitrary parameters in these solutions,the dynamic properties of some acquired solutions are represented graph-ically and *** particular,the dynamics of the bright solitons,dark solitons,mixed bright-dark solitons,W-shaped solitons,M-shaped solitons,periodic waves,and other soliton-type *** re-sults demonstrated that the proposed technique is highly efficient and effective for the aforementioned problems,as well as other nonlinear problems that may arise in the fields of mathematical physics and engineering.

关键词： CNLS equation Modiﬁed Sardar sub-equation method KdV equation Solitons Long and short waves

伊尔加兹山脉冰缘地貌发育和土壤形成及其气候的影响(土耳其黑海西岸)

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Journal of Geographical Sciences 2024年第3期34卷 543-570页

作者： DEDE Volkan DENGIZ Orhan DEMIRAG TURAN inci TüRKES Murat senol Hüseyin SERIN Soner Department of Geography Ardahan UniversityArdahan75002Türkiye Department of Soil Science and Plant Nutrition Faculty of AgricultureOndokuz Mayıs UniversitySamsun55139Türkiye Department of Geography Faculty of Human and Social SciencesSamsun UniversitySamsun55080Türkiye Center for Climate Change and Policy Studies Boğaziçi Universityİstanbul34342Türkiye Faculty of Agriculture Department of Soil Science and Plant NutritionIsparta University of Applied SciencesIsparta32200Türkiye Institute of Social Sciences İstanbul Universityİstanbul34119Türkiye

The main aims of the current study are to determine the morphological features of the periglacial landforms(non-sorted step,mud circle,stony earth circle,thufur,and congeliturbation)located on the Ilgaz Mountains,examine the physicochemical and mineralogical properties with pedological processes of the soils,and assess of the effects of climatic conditions controlling the development of *** Ilgaz Mountains(2587 m a.s.l.),located in the Western Black Sea Region,within the Anatolian Mountains,are important in terms of periglacial landforms(mud circles,stony earth circles,thufurs,non-sorted steps,non-sorted stripes,congeliturbation deposits,and block currents).The descriptive statistics of 123 periglacial landforms measured by fieldworks were *** distribution of freezing and thawing in the Ilgaz Mountains throughout the year was evaluated,and it was found that freezing takes place between December and March,freezing-thawing takes place in April,May,October and November,and thawing takes place between June and *** to soil properties,organic matter content changes from 1.88%to 12.72%in non-sorted step soils,while it is between 2.03%and 12.24%in stony earth circle *** organic matter is observed to be close to congeliturbation deposits at lower ratios compared to non-sorted steps,stony earth circles and mud *** soil reactions on stony earth circles and non-sorted steps vary between slightly acidic and slightly *** the other hand,soil samples taken from the mud circles are different from those taken from the non-sorted steps and stony earth *** soil reaction is acidic,and pH changes between 4.86 and *** lime content also varies between 2.81%and 32.08%,with an average of 12.02%.The texture properties of soils are dominantly loam and clay loam,as in the non-sorted steps,stony earth circles,and mud *** their mineralogical properties,the XRD study was carried out to determine the primer mineral

关键词： periglacial landforms soil formation climate effect Ilgaz Mountains Türkiye

Analytical and approximate solutions of(2+1)-dimensional time-fractional Burgers-Kadomtsev-Petviashvili equation

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Communications in Theoretical Physics 2020年第5期72卷 21-31页

作者： Mehmet senol Department of Mathematics Nevsehir Haci Bektas Veli UniversityNevsehirTurkey

In this paper,we applied the sub-equation method to obtain a new exact solution set for the extended version of the time-fractional Kadomtsev-Petviashvili equation,namely Burgers-Kadomtsev-Petviashvili equation(Burgers-K-P)that arises in shallow water ***,using the residual power series method(RPSM),approximate solutions of the equation were obtained with the help of the Mathematica symbolic computation *** also presented a few graphical illustrations for some *** fractional derivatives were considered in the conformable *** of the obtained solutions were replaced back in the governing equation to check and ensure the reliability of the *** numerical outcomes confirmed that both methods are simple,robust and effective to achieve exact and approximate solutions of nonlinear fractional differential equations.

关键词： fractional partial differential equations Burgers-Kadomtsev-Petviashvili equation conformable fractional derivative sub-equation method residual power series method

Multiple bifurcations in an early brain tumor model with piecewise constant arguments

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International Journal of Biomathematics 2018年第4期11卷 197-215页

作者： senol Kartal Department of Science and Mathematics Education Nevsehir Haci Bektas Veli University Nevsehir 50300 Turkey

In this paper, a differential equation with piecewise constant arguments modeling an early brain tumor growth is considered. The discretization process in the interval t ∈ [n, n＋1） leads to two-dimensional discrete dynamical system. By using the Schur-Cohn criterion, stability conditions of the positive equilibrium point of the system are obtained. Choosing appropriate bifurcation parameter, the existence of Neimark-Sacker and flip bifurcations is verified. In addition, the direction and stability of the Neimark-Sacker and flip bifurcations are determined by using the normal form and center manifold theory. Finally, the Lyapunov exponents are numerically computed to characterize the complexity of the dynamical behaviors of the system.

关键词： Piecewise constant arguments difference equation stability flip andNeimark Sacker bifurcations Lyapunov exponents.

SYNTHESIS,CHARACTERIZATION AND ANTIMICROBIAL PROPERTIES OF 4-[(4-HYDROXYBENZYLIDENE)AMINO]PHENOL AND ITS POLYMER

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Chinese Journal of Polymer Science 2007年第5期25卷 461-472页

作者： Ismet Kaya Suleyman Culhaoglu Dilek senol Department of Chemistry Faculty of Science and Arts Canakkale Onsekiz Mart University TR-17020 Canakkale Turkey

The oxidative polycondensation reaction conditions of 4-[（4-hydroxybenzylidene） amino] phenol （4-HBAP） were studied with H2O2, air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90℃. The structures of the obtained monomer and polymer were confirmed by FT-IR, UV-Vis, 1H- and 13C-NMR and elemental analysis. The characterization was made by TG-DTA, size exclusion chromatography （SEC） and solubility tests. At the optimum reaction conditions, the yield of poly[4-（4-hydroxybenzylidene amino） phenol] （P-4-HBAP） was found to be 48.3% （for H2O2 oxidant）, 80.5% （for air O2 oxidant） and 86.4% （for NaOCl oxidant）. According to the SEC analysis, the number-average molecular weight （Mn）, weight-average molecular weight （Mw） and polydispersity index （PDI） values of P-4-HBAP was found to be 8950, 10970 g tool^-1 and 1.225, respectively, using H202; and l l610, 15190 g tool^-1 and 1.308 respectively, using air 02 and 7900, 9610 g mol^-1 and 1.216, respectively, using NaOC1. According to TG-DTA analyses, P-4-HBAP was more stable than 4-HBAP against thermal decomposition. The weight loss of P-4-HBAP was found to be 49.27% at 1000℃. The highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO） values calculated from electrochemical measurement. Electrochemical energy gaps （Eg＇） of 4-HBAP and P-4-HBAP were found to be -5.46, -5.28; -2.26, -2.67; 3.20 and 2.61 eV, respectively. According to UV-Vis measurements, optical band gap （Eg） of 4-HBAP and P-4-HBAP were found to be 3.34 and 3.01 eV, respectively. Also, antimicrobial activities of 4-HBAP and P-4-HBAP were examined against selected some bacteria. The electrical conductivity of the polymer was measured after doping with iodine.

关键词： Air oxygen H2O2 NaOCl Poly[4-(4-hydroxybenzylidene amino) phenol] Oxidative polycondensation Thermal analysis Conductivity Antimicrobial and bad gap.

Efficacy of intramuscular diclofenac and fluid replacement in prevention of post-ERCP pancreatitis

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World Journal of Gastroenterology 2009年第32期15卷 3999-4004页

作者： Altug senol Ulku Saritas Halil Demirkan Department of Gastroenterology Suleyman Demirel University School of Medicine32260 IspartaTurkey Department of Internal Medicine Suleyman Demirel University School of Medicine32260 IspartaTurkey

AIM： TO assess the efficacy of intramuscular diclofenac and fluid replacement for prevention of post-endoscopic retrograde cholangiopancreatography （ERCP） pancreatitis.METHODS： A prospective, placebo-controlled study was conducted in 80 patients who underwent ERCP. Patients were randomized to receive parenteral diclofenac at a loading dose of 75 mg followed by the infusion of 5-10 mL/kg per hour isotonic saline over 4 h after the procedure, or the infusion of 500 mL isotonic saline as placebo. Patients were evaluated clinically, and serum amylase levels were measured 4, 8 and 24 h after the procedure.RESULTS： The two groups were matched for age, sex, underlying disease, ERCP findings, and type of treatment. The overall incidence of pancreatitis was 7.5% in the diclofenac group and 17.5% in the placebo group （12.5% in total）. There were no significant differences in the incidence of pancreatitis and other variables between the two groups. In the subgroup analysis, the frequency of pancreatitis in the patients without sphincter of Oddi dysfunction （SOD） was significantly lower in the diclofenac group than in the control group （ρ = 0.047）.CONCLUSION： Intramuscular diclofenac and fluid replacement lowered the rate of pancreatitis in patients without SOD.

关键词： Endoscopic retrograde cholangiopancreatography Pancreatitis Diclofenac Nonsteroidal antiinflammatory drugs Fluid replacement

Complex dynamics of COVID-19 mathematical model on Erdos-Rényi network

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生物数学学报:英文版 2023年第5期16卷 193-215页

作者： Neriman Kartal senol Kartal Department of Science and Mathematics Education Faculty of Education Nevsehir Haci Bektas Veli University Nevsehir 50300Turkey

In this study,a conformable fractional order Lotka-Volterra predator-prey model that describes the COVID-19 dynamics is *** using a piecewise constant approximation,a discretization method,which transforms the conformable fractional-order differential equation into a difference equation,is *** conditions for ensuring the stability of the equilibrium points of the discrete system are determined by using Schur-Cohn *** analysis shows that the discrete system exhibits Neimark-Sacker bifurcation around the positive equilibrium point with respect to changing the parameter d and *** Lyapunov exponents show the complex dynamics of the discrete *** addition,the COVID-19 mathematical model consisting of healthy and infected populations is also studied on the Erdos Rényi *** the coupling strength reaches the critical value,then transition from nonchaotic to chaotic state is observed in complex dynamical ***,it has been observed that the dynamical network tends to exhibit chaotic behavior earlier when the number of nodes and edges *** these theoretical results are interpreted biologically and supported by numerical simulations.

关键词： Piecewise constant arguments difference equation stability Neimark-Sacker bifurcation complex network