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Exploration of Green Alternatives to 6PPD (P-Phenylenediamine) Used as Antiozonant and Antioxidant in the Rubber Industry

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Materials Sciences and Applications 2024年第4期15卷 87-100页

作者： emine Demir Husnu Gerengi Kerem Savcı Gasim Altundal Canan yüksel Doğaç Çağıl Anlas Tyre Company R&D Center D&#252zce T&#252rkiye Department of Mechanical Engineering Faculty of Engineering D&#252zce University D&#252zce T&#252rkiye The Koc High School &#304stanbul T&#252rkiye

Antiozonants and antioxidants are additives commonly used in the rubber industry to enhance the durability and performance of rubber products. Ozone, present in the atmosphere, can cause rubber to degrade over time through a process known as ozone cracking. These rubber additives are added to rubber compounds to protect against this degradation. They work by reacting with ozone, preventing it from attacking and breaking the molecular chains in the rubber, helping to maintain the structural integrity of the rubber product. It is now well known that 6PPD contributes to the extension of the service life of rubber products. However, recent studies have shown that 6PPD can be harmful to the environment, especially when end-of-life tyres (ELTs) are contaminated with the water. With the effect of ozone, 6PPD is converted to 6PPD quinone, which is toxic enough to kill some sensitive fish species such as Coho Salmon (Oncorhynchus kisutch). This study drew attention to new chemical compounds and natural products that can be used as antiozonants and antioxidants in the rubber industry instead of 6PPD. Although the scientific studies are promising, the fact that 6PPD is still used in production shows that more scientific studies and social awareness need to be developed in this area.

关键词： 6PPD Coho Salmon Antiozonant Antioxidant

Risk factors and mortality rates of carbapenem-resistant Gram-negative bacterial infections in intensive care units

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Journal of Intensive Medicine 2024年第3期4卷 347-354页

作者： Tulay Orhan Kuloglu Gamze Kalin Unuvar Fatma Cevahir Aysegul Ulu Kilic emine Alp Infection Control Committee Faculty of MedicineErciyes UniversityKayseriTurkey Department of Infectious Diseases Faculty of MedicineErciyes UniversityKayseriTurkey Programme of First and Emergency Aid Sakarya UniversitySakaryaTurkey Department of Infectious Diseases Faculty of MedicineYıldırım Beyazıt UniversityAnkaraTurkey

Background The prevalence of hospital-acquired infections caused by carbapenem-resistant gram-negative bacteria(CRGNB)is increasing *** risk factors have been associated with such *** present study aimed to identify risk factors and determine the mortality rates associated with CRGNB infections in intensive care *** This retrospective case-control study was conducted at Erciyes University Hospital(Kayseri,Turkey)between January 2017 and December *** and laboratory data were obtained from the Infection Control Committee data and record *** who had CRGNB infection 48–72 h after hospitalization were assigned to the case group,while those who were not infected with CRGNB during hospitalization formed the control *** factors,comorbidity,demographic data,and mortality rates were compared between the two *** Approximately 1449 patients(8.97%)were monitored during the active follow-up period;of those,1171 patients were included in this *** infection developed in 14 patients(70.00%)who had CRGNB colonization at admission;in 162(78.26%)were colonized during hospitalization,whereas 515(54.56%)were not *** was no significant difference in age,sex(male/female)or *** total length of hospital stay was statistically significantly longer(P=0.001)in the case group(median:24[interquartile range:3–378]days)than the control group(median:16[interquartile range:3–135]days).The rates of colonization at admission(25.5%;vs.10.6%,P=0.001)and mortality(64.4%vs.45.8%,P=0.001)were also significantly higher in the cases than in the control group,*** the univariate analysis,prolonged hospitalization,the time from intensive care unit admission to the development of infection,presence of CRGNB colonization at admission,transfer from other hospitals,previous antibiotic use,enteral nutrition,transfusion,hemodialysis,mechanical ventilation,tracheostomy,reintubation,central veno

关键词： Multidrug resistance Gram-negative bacteria Infection Intensive care units

Comparison of the clinical efficacy of two different types of post systems which were restored with composite restorations

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World Journal of Clinical Cases 2018年第3期6卷 27-34页

作者： Buket Ayna Emrah Ayna Sema Celenk emine Goncü Bacaran Berivan Dündar yιlmaz Ìbrahim Halil Tacir Mehmet Cudi Tuncer Department of Pedodontics Faculty of Dentistry Dicle University Department of Prosthodontics Faculty of Dentistry Dicle University Department of Anatomy Faculty of Medicine Dicle University

AIM To compare the efficacy of resin composite restorations, retained with either polyethylene or zirconia-rich glass fiber posts. METHODS Sixty-two single rooted maxillary and mandibularcentral incisor teeth in forty-four patients (15 males and 29 females; age range 15-32 years) were restored either with an ultrahigh molecular weight polyethylene(UHMWP) fiber post (Bondable Reinforcement Ribbon, DENSE, Ribbond, Seattle, WA, United States) or a zircon-rich glass fiber post (Snowpost, Lot H 040; Carbotech, Ganges, France). Then, direct resin composite restoration (Clearfil AP-X, Kuraray) was performed for both post systems in tooth color suitable. Patients were recalled for routine inspections at 6 mo, 1, 2 and 3 *** The restorations were assessed during each recall evaluation according to predetermined clinical and radiographic criteria (periapical lesion; marginal leakage and integrity; color stability; surface stain and loss of retention of the post or the composite buildup material). The follow-up data showed no significant difference in these criteria between polyethylene fibre posts and zirconia-rich glass fibre *** The efficacy of resin composite restorations, retained with either polyethylene or zirconia-rich glass fiber posts were similar, suggesting that both types of fiber post can be used successfully to help retain resin composite restorations.

关键词： Polyethylene fiber Zircon-rich glass fiber Direct composite

Exploration of Green Alternatives to 6PPD (P-Phenylenediamine) Used as Antiozonant and Antioxidant in the Rubber Industry

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Covering the More Visible Region by Electrochemical Copolymerization of Carbazole and Benzothiadiazole Based Donor-Acceptor Type Monomers

Materials Sciences and Applications（材料科学与应用期刊） 2024年第4期 87页

作者： emine Demir Husnu Gerengi Kerem Savcı Gasim Altundal Canan yüksel Doğaç Çağıl

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Chinese Journal of Polymer Science 2019年第1期37卷 28-35页

作者： emine Gul Cansu-Ergun Department of Electrical and Electronics Engineering Baskent University

An electrochromic copolymer film of 2-(3,3-dihexyl-3,4-dihydro-2 H-thieno[3,4-b][1,4]dioxepin-6-yl)-7-(3,3-dihexyl-3,4-dihydro-2 H-thieno[3,4-b][1,4]dioxepin-8-yl)-9 H-carbazole(M1) and 4,7-bis(thiophen-2-yl)benzo[c][1,2,5]thiadiazole(M2) was prepared via electrochemical technique. The copolymerization was performed with one to one monomer feed ratio. Electrochemical and optical properties of the resulting copolymer film(P3) and the homopolymer films of M1 and M2(P1 and P2) were investigated by using cyclic voltammetry and UV-Vis spectrometry techniques, and the corresponding results were compared. Incorporation of M1 and M2 into copolymer matrix was clearly observed on the resulting cyclic voltammograms and UV-Vis spectra. P3 covered the visible regions coming from both P1 and P2, and exhibited a neutral state darker color than those of homopolymers. P3 film was found to have a multichromic behavior, appearing as brown in its neutral state while changing its color upon oxidation to dark-gray(at about 0.3 V), to blue(at about 0.6 V) and finally to grayish cyan(beyond 0.9 V), with a corresponding optical band gap of 1.65 eV.

关键词： Electrochemical polymerization Copolymer Electrochromic polymers

On modeling with multiplicative differential equations

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Applied Mathematics(A Journal of Chinese Universities) 2011年第4期26卷 425-438页

作者： Agamirza E.Bashirov emine Misirli ycel Tandogdu Ali zyapici Department of Mathematics Eastern Mediterranean University Department of Mathematics Ege University Department of Computer Engineering Lefke European University

This work is aimed to show that various problems from different fields can be modeled more efficiently using multiplicative calculus, in place of Newtonian calculus. Since multiplicative calculus is still in its infancy, some effort is put to explain its basic principles such as exponential arithmetic, multiplicative calculus, and multiplicative differential equations. Examples from finance, actuarial science, economics, and social sciences are presented with solutions using multiplicative calculus concepts. Based on the encouraging results obtained it is recommended that further research into this field be vested to exploit the applicability of multiplicative calculus in different fields as well as the development of multiplicative calculus concepts.

关键词： Gompertz function elasticity exponential arithmetic multiplicative calculus growth.

Nonlinear Intersubband Transitions in Square and Graded Quantum Wells Modulated by Intense Laser Field

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Chinese Physics Letters 2014年第12期31卷 95-98页

作者： emine Ozturk Ismail Sokmen Department of Physics Cumhuriyet University Sivas 58140 Turkey Department of Physics Dokuz Eylfil University Izmir 35160 Turkey

There has been increasing interest, both exper- imentally and theoretically, in the investigation of low-dimensional semiconductor heterostructures due to their intrinsic physical properties and technological applications in electronic and optoelectronic devices. The studies on quantum heterostructures have opened a new field in fundamental physics, and also offer a wide range of potential applications for optoelectronic devices. By varying the profile of a semiconductor quantum well （QW）, both the subband state energies and their wave functions change, and so do various physical properties depending on them.

关键词： QUANTUM wells LASER beams REFRACTIVE index NONLINEAR optics MASS attenuation coefficients LIGHT absorption

Electronic Properties of p-Type δ-Doped GaAs Structure under Electric Field

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Chinese Physics Letters 2008年第4期25卷 1415-1418页

作者： emine OZTURK Ismail SOKMEN Department of Physics Cumhuriyet University 58140 SIVAS Turkey Department of Physics Dokuzeylul University IZMIR Turkey

We theoretically investigate the electronic properties of p-type δ-doped GaAs inserted into a quantum well under the electric field, at T = 0 K. We will investigate the influence of the electric field on the δ-doping concentration for a uniform distribution. The depth of confining potential, the density profile, the Fermi level, the subband energies and the subband populations calculate by solving the Schrodinger and Poisson equations self consistently. It is found that the changes of the electronic properties are quite sensitive to the applied electric field and the doping concentration. As different from single n-type δ-doped structure, we see a replace between the ground light-hole （lh1 ） subband and the first excited heavy-hole （hh2） subband whenever the external electric field reaches a critical value. We find the abrupt changing of the subband energies and the subband populations whenever the applied electric field reaches a certain value. Also, it is found that the heavy-hole subbands contain many more energy states than the light-hole ones, the population of the heavy-hole levels represent approximately 91% of all the carriers.

关键词： supernova explosion proto-neutron star shock wave

Molecular Dynamics Simulation of 4-N-Hexyl-4＇-Cyanobiphenyl Adsorbed at the Air-Water Interface

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Chinese Physics Letters 2018年第4期35卷 86-90页

作者： Oguz Gürbulak emine Cebe Department of Physics Faculty of Science Ege University Bornova 35100 Izmir Turkey

The interfacial behavior of 4-n-hexyl-4＇-cyanobiphenyl（6CB） molecules at the air-water interface is investigated by full atomistic molecular dynamics simulations. To understand the morphology and the structure of adsorbed 6CB molecules in detail, the snapshots and mass density profiles of the simulation system are generated. The average tilt angles between the interface normal and various vectors defined in the rigid and alkyl parts of 6CB are in good agreement with the experimental data available. The interfacial thickness and monolayer width are obtained from the mass density profiles of water and 6CB phase, respectively. The second and fourth rank orientational order parameters of cyanobiphenyl core are found to be larger than those of an elastic alkyl *** order parameters for 6CB are also calculated. The calculated oxygen-oxygen radial distribution function and hydrogen bonding statistics for bulk water are compared with those for the interfacial region. The surface tensions of the systems are calculated. All simulation results are compared with the available literature data.

关键词： Oxygen