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BSN:Photometric Light Curve Analysis of Two Contact Binary Systems LS Del and V997 Cyg

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Research in Astronomy and Astrophysics 2024年第4期24卷 192-213页

作者： Atila Poro Mehmet Tanriver Elham Sarvari Shayan Zavvarei Hossein Azarara Laurent Corp Sabrina Baudart Asma Ababafi Nazanin Kahali Poor Fariba Zare Ahmet bulut Ahmet Keskin Astronomy Department of the Raderon AI Lab. BurnabyBC.Canada Department of Astronomy and Space Science Faculty of ScienceErciyes UniversityKayseri TR-38039Turkiye Erciyes University Astronomy and Space Science Observatory Application and Research CenterKayseri TR-38039Turkiye Independent Astrophysics Researcher TehranIran Department of Physics Shahid Beheshti UniversityTehranIran Faculty of Physics Shahid Bahonar University of KermanP.O.Box 76175KermanIran Double Stars Committee SociétéAstronomique de FranceParisFrance Dez Astronomical Association Khouzestan ProvinceDezfulIran Department of Physics Amirkabir University of TechnologyTehranIran Department of Physics Faculty of SciencesCanakkale Onsekiz Mart UniversityTerzioglu KampusuTR-17020CanakkaleTurkiye Astrophysics Research Center and Observatory Canakkale Onsekiz Mart UniversityTerzioğlu KampusuTR-17020CanakkaleTürkiye

The light curve analyses and orbital period variations for two contact binary stars,LS Del and V997 Cyg,are presented in this work which was conducted in the frame of the Binary Systems of South and North project ground-based photometric observations were performed at two observatories in *** used the Transiting Exoplanet Survey Satellite(TESS)data for extracting times of minima and light curve analysis of the targe *** O-C diagram for both systems displays a parabolic *** Del and V997 Cyg’s orbital periods are increasing at rates of dP/dt=7.20×10^(-08)days yr^(-1)and dP/dt=2.54×10^(-08)days yr^(-1),respectively Therefore,it can be concluded that mass is being transferred from the less massive star to the more massive component with a rate of dM/dt=-1.96×10^(-7)M_(⊙)yr^(-1)for the LS Del system,and dM/dt=-3.83×10^(-7)M_(⊙)yr-1for V997 *** parameters of a third possible object in the system are also *** PHysics Of Eclipsing BinariEs Python code was used to analyze the light *** light curve solutions needed a cold starspot due to the asymmetry in the LS Del system’s light curve *** mass ratio fill-out factor,and star temperature all indicate that both systems are contact binary types in this *** methods were applied to estimate the absolute parameters of the systems:one method relied on the parallax of gaia DR3,and the other used a P-M *** positions of the systems are also depicted on the M-L,M-R q-L_(ratio),and logM_(tot)-logJ_(0)*** recommend that further observations and investigations be done on the existence of a fourth body in this system.

关键词： (stars:)binaries:eclipsing methods:observational stars:individual(LS Del and V997 Cyg)

Lacidipine,thiamine pyrophosphate and their combination on the ocular ischemic syndrome induced by bilateral common carotid artery ligation

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 815-821页

作者： Ibrahim Cicek Ahmet Mehmet Somuncu Durdu Altuner Bahadir Suleyman Renad Mammadov Seval bulut Taha Abdulkadir Coban Tugba Bal Tastan Halis Suleyman Department of Ophthalmology Faculty of MedicineErzincan Binali Yildirim UniversityErzincan 24100Turkey Department of Pharmacology Faculty of MedicineErzincan Binali Yildirim UniversityErzincan 24100Turkey Department of Clinical Biochemistry Faculty of MedicineErzincan Binali Yildirim UniversityErzincan 24100Turkey Department of Histology and Embryology Faculty of MedicineErzincan Binali Yildirim University ErzincanErzincan 24100Turkey

AIM:To investigate the effect of lacidipine,thiamine pyrophosphate(TPP)and the combination of lacidipine and TPP against oxidative and inflammatory eye damage induced by bilateral common carotid artery ligation in ***:Male albino Wistar rats were categorized as those who underwent sham surgery(Sg),right and left common carotid cross-clamping and unclamping procedure(CCU),lacidipine+CCU(LCCU),TPP+CCU(TCCU),and combination of lacidipine and TPP(LTC)+CCU(LTCCU).One hour before anesthesia,the LCCU(n=6)received lacidipine(4 mg/kg,orally)and the TCCU(n=6)received TPP(20 mg/kg,intraperitoneally).The Sg(n=6)and CCU(n=6)received the same volume of distilled water from the same *** anesthesia(60 mg/kg ketamine,intraperitoneally),the necks of the rats were opened in the *** was created for 10min by placing clips on the right and left common carotid *** in the Sg only underwent subcutaneous *** 10min,the clips were removed and reperfusion was achieved for six ***,the animals were euthanized(120 mg/kg ketamine,intraperitoneally)and the levels of oxidant,antioxidant and proinflammatory cytokines in the eye tissues were *** retinal tissue of the eye was also examined ***:Lacidipine,TPP,and LTC significantly prevent the increase in malondialdehyde,tumor necrosis factoralpha,interleukin-1β(IL-1β),and IL-6 levels,decrease in total glutathione levels,superoxide dismutase and catalase activities and histopathological retinal damage in eye tissue induced by bilateral common carotid artery ligation in *** impact of these drugs on protection is determined to be LTC>lacidipine>***:As a result of the study,it is concluded that LTC may be more effective than lacidipine and TPP alone in treating ocular ischemic syndrome.

关键词： ocular ischemic syndrome lacidipine thiamine pyrophosphate oxidative stress

New Apsidal Motion in Four Eccentric Eclipsing Binaries:V610 Car,V944 Cep,V2815 Ori and V1260 Tau

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Research in Astronomy and Astrophysics 2022年第11期22卷 69-77页

作者： Ahmet bulut Department of Physics Faculty of Arts and SciencesCanakkale Onsekiz Mart UniversityTerzioglu CampusTR-17020CanakkaleTurkiye Astrophysics Research Centre and Observatory Canakkale Onsekiz Mart UniversityTerzioglu CampusTR-17020CanakkaleTurkiye

This paper presents an apsidal motion *** apsidal motion analysis of the eccentric eclipsing binaries V610 Car(P=4.84 days),V944 Cep(P=6.56 days),V2815 Ori(P=2.13 days),and V1260 Tau(P=5.43 days)was performed using minima times from the O-C gateway database,ASAS-3,ASAS-SN,and TESS,following Lacy’s *** rates of change of periastron longitude were found to be 0.0253±0.0041,0.0347±0.0015,0.0288±0.0010 and0.0294±0°.0079 cycle^(-1),*** the light curve study,the first photometric mass ratio of V944 Cep was found to be q=1.4994±0.0012.A new light curve of V944 Cep was obtained using TESS *** first absolute dimensions of V944 Cep were M_(1)=1.10±0.01 M_(⊙),M_(2)=1.64±0.02 M_(⊙),R_(1)=2.04±0.37 R_(⊙),R_(2)=3.77±0.67 R_(⊙)for the hotter primary component(T_(1)=4925 K),and M_(1)=1.04±0.01 M_(⊙),M_(2)=1.57±0.02 M_(⊙),R_(1)=2.26±0.36 R_(⊙),R_(2)=3.74±0.59 R_(⊙)for the cooler primary component(T_(1)=4475 K).For V610 Car,V944 Cep,V2815 Ori and V1260 Tau,the apsidal motion periods were found to be 188±26 yr,186±8 yr,73±3 yr and 182±38 yr,*** V944 Cep,the internal structural constants of the component stars log_(k2,obs)=-2.05±0.01 and log_(k2,theo)=-1.83 for hotter primary component and log_(k2,obs)=-1.97±0.01 and log_(k2,theo)=-1.89 for cooler primary component were calculated.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters techniques:photometric

Removal of heavy metals from aqueous solution by sawdust adsorption

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Journal of Environmental Sciences 2007年第2期19卷 160-166页

作者： bulut Yasemin TEZ Zeki Faculty of Arts and Sciences Department of Chemistry University of Dicle21280 DiyarbakirTurkey. Faculty of Techniqual Education Department of Textile Marmara UniversityGztepeIstanbulTurkey

The adsorption of lead, cadmium and nicel from aqueous solution by sawdust of walnut was investigated. The effect of contact time, initial metal ion concentration and temperature on metal ions removal has been studied. The equilibrium time was found to be of the order of 60 min. Kinetics fit pseudo first-order, second-order and intraparticle diffusion models, hence adsorption rate constants were calculated. The adsorption data of metal ions at temperatures of 25, 45 and 60~C have been described by the Freundlich and Langmuir isotherm models. The thermodynamic parameters such as energy, entropy and enthalpy changes for the adsorption of heavy metal ions have also been computed and discussed. Ion exchange is probably one of the major adsorption mechanisms for binding divalent metal ions to the walnut sawdust. The selectivity order of the adsorbent is Pb（I1）~Cd（II）〉Ni（I1）. From these results, it can be concluded that the sawdust of walnut could be a good adsorbent for the metal ions from aqueous solutions.

关键词： adsorption heavy metals sawdust kinetic thermodynamic parameters

A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(Ⅳ), Se(Ⅵ)) at trace levels in natural lake and river water samples

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Rare Metals 2011年第5期30卷 477-487页

作者： Ramazan gürkan Halil brahim Ulusoy Mehmet Akay Pinar bulut Department of Chemistry Faculty of Science University of Cumhuriyet

A novel catalytic kinetic method is proposed for the determination of Se（Ⅳ）, Se（Ⅵ）, and total inorganic selenium in water based on the catalytic effect of Se（Ⅳ） on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the two calibration graphs are linear with a good correlation coefficient in the range 2-20 and 20-200 μg·L-1 of Se（Ⅳ） for the fixed-time method at 30℃. The experimental and theo- retical detection limits of the developed kinetic method were found to be 0.21 and 2.50 μg·L-1 for the fixed-time method （3 min）. All of the variables that affect the sensitivity at 645 nm were investigated, and the optimum conditions were established. The interference effect of various cations and anions on the Se（Ⅳ） determination was also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange resin such as Amberlite IR120 plus as long as chelating agents of thiourea and thiosulphate. The proposed kinetic method was validated statistically and through recovery studies in natural water samples. The relative standard deviations （RSDs） for ten replicate measurements of 2, 10, and 20 μg·L-1 of Se（Ⅳ） change between 0.35% and 5.58%, while the RSDs for ten replicate measurements of 3, 6, and 12 μg·L-1 of Se（Ⅵ） change between 0.49% and 1.61%. Analyses of a certified standard reference material （NIST SRM 1643e） for selenium using the fixed-time method showed that the proposed kinetic method has good accuracy. The Se（Ⅳ）, Se（Ⅵ）, and total inorganic selenium in lake and river water samples have been successfully determined by this method after selective reduction of Se（Ⅵ） to Se（Ⅳ）.

关键词： selenium speciation Celestine blue catalytic effect kinetic spectrophotometry natural waters

Optical solitons and modulation instability analysis of the(1+1)-dimensional coupled nonlinear Schrodinger equation

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Communications in Theoretical Physics 2020年第2期72卷 17-22页

作者： Tukur Abdulkadir Sulaiman Hasan bulut Firat University Faculty of ScienceElazigTurkey Federal University DutseFaculty of ScienceJigawaNigeria Final International University Faculty of EducationKyreniaCyprus

This study successfully reveals the dark,singular solitons,periodic wave and singular periodic wave solutions of the(1+1)-dimensional coupled nonlinear Schr?dinger equation by using the extended rational sine-cosine and rational sinh-cosh *** modulation instability analysis of the governing model is *** using the suitable values of the parameters involved,the 2-,3-dimensional and the contour graphs of some of the reported solutions are plotted.

关键词： the coupled nonlinear Schrodinger’s equation optical soliton modulation instability

The First Photometric Study of W UMa Binary System V1833 Ori

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Research in Astronomy and Astrophysics 2022年第8期22卷 258-269页

作者： Mehmet Tanrıver Ahmet bulut Astronomy and Space Science Science FacultyUniversity of ErciyesTR-38039KayseriTürkiye Erciyes University Astronomy and Space Science Observatory Application and Research CenterTR-38039KayseriTürkiye Department of Physics Faculty of Arts and SciencesÇanakkale Onsekiz Mart UniversityTerzioglu CampusTR-17020ÇanakkaleTürkiye Astrophysics Research Center and Observatory Çanakkale Onsekiz Mart UniversityTerzioglu CampusTR-17020ÇanakkaleTürkiye

The first photometric solution in the B,V,R_(c) and I_(c) filters of the short period V1833 Ori eclipsing binary is presented based on new ground-based CCD photometric *** analyzed the BVRI photometric light curves of the system,using PHOEBE 0.31 a,a binary star modeling program,with the Wilson-Devinney method based on Roche geometry to achieve the best accordance with the photometric observations to determine their absolute parameters from the light *** updated the ephemeris of V1833 Ori using two new light curve minima derived by our new observational data from those collected in the literature and analyzed the change of the system's orbital *** O-C analysis indicates that the variations of the orbital period of V1833 Ori with time are increasing at a rate of 3.03×10^(-7)days yr^(-1).The distance of V1833 Ori is 173.7±15.6 *** the solutions,we find that V1833 Ori is an A-subtype W UMa overcontact binary with q=0.701 mass ratio and f=1.14 fill-out *** HR diagram positions of the eclipsing binary system's components are *** system's absolute dimensions were compared to those of similar binaries in the log T_(eff)-log L,logM-logL,1 ogM-logR and logM-log J_(0)diagrams.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters stars:individual(V1833 Ori)

The effects of season on fatty acid composition and ω3/ω6 ratios of northern pike(Esox lucius L.,1758) muscle lipids

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Chinese Journal of Oceanology and Limnology 2015年第1期33卷 70-76页

作者： MERT Ramazan bulut Sait KONUK Muhsin Neveshir Haci Bektas Veli University Department of BiologyNevsehir 50300Turkey Akdeniz University Department of Science EducationAntalya 07058Turkey Uskiidar University Department of Molecular Biology and GeneticsIstanbul 34662Turkey

In the present study, the effects of season on fatty acid composition, total lipids, and ω3/ω6 ratios of northern pike muscle lipids in Klzlhrmak River （Klrlkkale, Turkey） were investigated. A total of 35 different fatty acids were determined in gas chromatography. Among these, palmitic, oleic, and palmitoleic acids had the highest proportion. The main polyunsaturated fatty acids （PUFAs） were found to be docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid. There were more PUFAs than monounsaturated fatty acids （MUFA） in all seasons. Similarly, the percentages of ω3 fatty acids were higher than those of total ω6 fatty acids in the fatty acid composition. ω3/ω6 ratios were calculated as 1.53, 1.32, 1.97, and 1.71 in spring, summer, autumn and winter, respectively. Overall, we found that the fatty acid composition and ω3/ω6 fatty acid ratio in the muscle of northern pike were significantly influenced by season.

关键词： freshwater fish fatty acid composition omega-3 PUFA lipid content season

geotechnical investigations and remediation design for failure of tunnel portal section： a case study in northern Turkey

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Journal of Mountain Science 2017年第6期14卷 1140-1160页

作者： Ayberk KAYA Kadir KARAMAN Fikri bulut Recep Tayyip Erdogan University Faculty of Engineering Department of Geological Engineering 53100 Rize Turkey Karadeniz Technical University Faculty of Engineering Department of Mining Engineering 61080 Trabzon Turkey Karadeniz Technical University Faculty of Engineering Department of Geological Engineering 61080 Trabzon Turkey

Mass movements are very common problems in the eastern Black Sea region of Turkey due to its climate conditions, geological, and geomorphological characteristics. High slope angle, weathering, dense rainfalls, and anthropogenic impacts are generally reported as the most important triggering factors in the region. Following the portal slope excavations in the entrance section of Cankurtaran tunnel, located in the region, where the highly weathered andesitic tuff crops out, a circular toe failure occurred. The main target of the present study is to investigate the causes and occurrence mechanism of this failure and to determine the feasible remedial measures against it using finite element method(FEM) in four stages. These stages are slope stability analyses for pre-and postexcavation cases, and remediation design assessments for slope and tunnel. The results of the FEM-SSR analyses indicated that the insufficient initial support design and weathering of the andesitic tuffs are the main factors that caused the portal failure. After installing a rock retaining wall with jet grout columns and reinforced slope benching applications, the factor of safety increased from 0.83 to 2.80. In addition toslope stability evaluation, the Rock Mass Rating(RMR), Rock Mass Quality(Q) and New Austrian Tunneling Method(NATM) systems were also utilized as empirical methods to characterize the tunnel ground and to determine the tunnel support design. The performance of the suggested empirical support design, induced stress distributions and deformations were analyzed by means of numerical modelling. Finally, it was concluded that the recommended stabilization technique was essential for the dynamic long-term stability and prevents the effects of failure. Additionally, the FEM method gives useful and reasonably reliable results in evaluating the stability of cut slopes and tunnels excavated both in continuous and discontinuous rock masses.

关键词： Portal failure Stability analysis Finite element method Tunnel support design Remedial measures Rock Mass Rating(RMR) Rock Mass Quality(Q) New Austrian Tunneling Method(NATM)