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Quantum spin Hall and quantum valley Hall effects in trilayer graphene and their topological structures

Chinese Physics B 2017年第12期26卷 481-490页

作者： Majeed ur Rehman A A Abid ICQD Hefei National Laboratory for Physical Sciences at Microscale Department of Physics University of Science and Technology of China Hefei 230026 China Key Laboratory of Geospace Environment(Chinese Academy of Sciences) Department of Geophysics and Planetary Science University of Science and Technology of China Hefei 230026 China

The present study pertains to the trilayer graphene in the presence of spin orbit coupling to probe the quantum spin/valley Hall effect. The spin Chern-number Cs for energy-bands of trilayer graphene having the essence of intrinsic spin-orbit coupling is analytically calculated. We find that for each valley and spin, Cs is three times larger in trilayer graphene as compared to single layer graphene. Since the spin Chern-number corresponds to the number of edge states, consequently the trilayer graphene has edge states, three times more in comparison to single layer graphene. We also study the trilayer graphene in the presence of both electric-field and intrinsic spin-orbit coupling and investigate that the trilayer graphene goes through a phase transition from a quantum spin Hall state to a quantum valley Hall state when the strength of the electric field exceeds the intrinsic spin coupling strength. The robustness of the associated topological bulk-state of the trilayer graphene is evaluated by adding various perturbations such as Rashba spin-orbit （RSO） interaction αR, and exchange-magnetization M. In addition, we consider a theoretical model, where only one of the outer layers in trilayer graphene has the essence of intrinsic spin-orbit coupling, while the other two layers have zero intrinsic spin-orbit coupling. Although the first Chern number is non-zero for individual valleys of trilayer graphene in this model, however, we find that the system cannot be regarded as a topological insulator because the system as a whole is not gaped.

关键词： trilayer graphene quantum spin Hall effect topological insulator quantum phase transition

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Mechanistic Transformations Involving Radical and Cationic Polymerizations

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Chinese Journal of Polymer Science 2020年第3期38卷 205-212,I0004页

作者： Gorkem yilmaz Yusuf Yagci Istanbul Technical university Department of ChemistryMaslak34469 IstanbulTurkey Center of Excellence for Advanced Materials Research(CEAMR)and Department of Chemistry Faculty of ScienceKing Abdulaziz University21589 JeddahSaudi Arabia

Mechanistic transformation approach has been widely applied in polymer synthesis due to its unique feature combining structurally different polymers prepared by different polymerization *** methods for the formation of block and graft copolymers through mechanistic transformation involve almost all polymerizations ***,certain polymerization processes require extensive purification processes,which can be time-consuming and *** developments on controlled/living polymerizations involving radical and cationic mechanisms with the ability to control molecular weight and functionality led to new pathways for mechanistic *** this mini-review,we systematically discussed relevant advances in the field through three main titles namely(i)from radical to cationic mechanism,(ii)from cationic to radical mechanism,and(iii)application of specific catalyst systems for both radical and cationic polymerizations.

关键词： Transformation Radical polymerization Cationic polymerization Controlled/living polymerization Photopolymerization

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Graft-versus-host disease after liver transplantation:A comprehensive literature review

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World Journal of Gastroenterology 2012年第37期18卷 5240-5248页

作者： Sami Akbulut Mehmet yilmaz Sezai yilmaz Liver Trans plant Institute Inonu University Faculty of Medicine

AIM： To determine the factors affecting mortality in pa- tients who developed graft-versus-host disease （GvHD） after liver transplantation （LT）. METHODS： We performed a review of studies of GvHD following LT published in the English literature and ac- cessed the PubMed, Medline, EBSCO, EMBASE, and Google Scholar databases. using relevant search phras- es, 88 articles were identified. Of these, 62 articles con- raining most of the study parameters were considered eligible for the study. Risk factors were first examined using a univariate Kaplan-Meier model, and variables with a significant association （P 〈 0.05） were then sub- jected to multivariate analyses using a Cox proportional- hazards model. RESuLTS： The 61 articles reported 87 patients, 58 male and 29 female, mean age, 40.4 ± 15.5 years （range： 8 mo to 74 years）, who met the inclusion criteria for the present study. Deaths occurred in 59 （67.8%） patients, whereas 28 （32.2%） survived after a mean follow-up period of 280.8 ± 316.2 d （range： 27-2285 d）. Among the most frequent symptoms were rash （94.2%）, fever （66.6%）, diarrhea （54%）, and pancytopenia （54%）. The average time period between LT and first symptom on- set was 60.6 ± 190.1 d （range： 2-1865 d）. The Kaplan- Meier analysis revealed that pancytopenia （42.8% vs 59.3%, P = 0.03）, diarrhea （39.2% vs 61.0%, P = 0.04）, age difference between the recipient and the donor （14.6 ± 3.1 years vs 22.6 ± 2.7 years, P 〈 0.0001）, and time From first symptom occurrence to diagnosis or treatment （13.3 ± 2.6 mo vs 15.0 ± 2.3 mo, P 〈 0.0001） were significant factors affecting mortality, whereas age, sex, presence of rash and fever, use of immunosuppressive agents, acute rejection before GvHD, etiological causes, time of onset, and donor type were not associated with mortality risk. The Cox proportional-hazards model, de- termined that an age difference between the recipient and donor was an independent risk Factor （P = 0.03; hazard ratio, 7.395, 95% confidence interval, 1.

关键词： Liver transplantation Graft-versus-host dis-ease Immunosuppression Rash Pancytopenia Diar-rhea Chimerism Age factors

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ELECTRORHEOLOGICAL PROPERTIES OF DIATOMITE/SILICONE OIL SuSPENSIONS uNDER DC FIELDS

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Chinese Journal of Polymer Science 2006年第5期24卷 463-471页

作者： Hasim yilmaz Chemistry Department Sciences FacultyHarran University63190 OsmanbeySanliurfaTurkey

In this study, electrorheological （ER） behavior of suspensions prepared from 3.0 and 9.0 μm diatomite particulate, dispersed in insulating silicone oil （SO） medium was investigated. Sedimentation stabilities of suspensions （c = 5 wt%） prepared using these diatomite powders were determined to be 32 days （d = 3 μm） and 24 days （d = 9 μm）, respectively. ER activity of all the suspensions was observed to increase with increasing electric field strength, concentration and decreasing shear rate. Shear stress of diatomite suspensions increased linearly with increasing concentrations of the particles and with the applied electric field strength. Electric field viscosity of all the suspensions decreased sharply with increasing shear rate and particle size, showing a typical shear thinning non-Newtonian visco-elastic behavior. Effects of high temperature and polar promoter onto ER activity ofdiatomite/SO system were also investigated.

关键词： Electrorheological fluids Diatomite/silicone oil suspensions Shear stress.

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The geometric resistivity correction factor for several geometrical samples

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Journal of Semiconductors 2015年第8期36卷 1-8页

作者： Serdar yilmaz Mersin university Science and Arts Faculty Physics Department Mersin university Advanced Technology Education Research and Application Center

This paper reviews the geometric resistivity correction factor of the 4-point probe DC electrical conduc- tivity measurement method using several geometrical samples. During the review of the literature, only the articles that include the effect of geometry on resistivity calculation were considered. Combinations of equations used for various geometries were also given. Mathematical equations were given in the text without details. Expressions for the most commonly used geometries were presented in a table for easy reference.

关键词： semiconductor four point probe conductivity measurement resistivity correction factor

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Comparisons of the suture zones along a geotraverse from the Scythian Platform to the Arabian Platform

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Geoscience Frontiers 2014年第6期5卷 855-875页

作者： Ali yilmaz Shota Adamia Hüseyin yilmaz Cumhuriyet university Engineering FacultyDepartment of Environmental EngineeringKayseri StreetCU.CampusTR-58140 SivasTurkey Nodia Institute of Geophysics 1M.Alexidze Str.0195TbilisiGeorgia Cumhuriyet university Engineering FacultyDepartment of Geophysical EngineeringTR-58140 SivasTurkey

The area from the Greater Caucasus to the southeast Turkey is characteri：;.ed and shaped by several major continental blocks. These are Scythian Platform, Pontian-Transcaucasu.,; Continent-Arc System （PTCAS）, the Anatolian-lranian and the Arabian Platforms. The aim of this paper is to define these continental blocks and describe and also compare their boundary relationships along the suture zones. The Scythian Platform displays the evidence of the Hercynian and Alpine orogens. This platform is separated from the PTCAS by the Greater Caucasus Suture Zone. The incipient collision began along this suture zone before middle-late Carboniferous whereas the final collision occurred before Oligocene. The PTCAS can be divided into four structural units：（1） the Georgian Block - northern part of the Pontian-Transcaucasian island-arc, （2） the southern and eastern Black Sea Coast-Adjara-Trialeti unit, （3） the Artvin-Bolnisi unit, comprising the northern part of the southern Transcaucasus, and （4） the Imbricated Bayburt-Garabagh unit. The PTCAS could be separated from the Anatolian Iranian Platform by the North Anatolian-Lesser Caucasus Suture （NALCS） zone. The initial collision was developed in this suture zone during Senonian-early Eocene and final collision before middle Eocene or Oligocene-Miocene. The Anatolian-lranian Platform （AIP） is made up of the Tauride Platform and its metamorphic equivalents together with Iranian Platform. It could be separated from the Arabian Platform by the Southeastern Anatolian Suture （SEAS） zone. The collision ended before late Miocene along this suture zone. The southernmost continental block of the geotraverse is the Arabian Platform, which constitutes the northern part of the Arabian-African Plate. This platform includes a sequence from the Precambrian felsic volcanic and clastic rocks to the Campanian-early Maastrichtian fiyschoidal clastics. All the suture zones include MORB and SSZ-types ophiolites in different ages. However, the ages of

关键词： Scythian Plattorm Arabian Platform Suture zones Ceotraverse

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Oxidative desulfurization of dibenzothiophene over Fe promoted Co–Mo/Al_2O_3 and Ni–Mo/Al_2O_3 catalysts using hydrogen peroxide and formic acid as oxidants

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Chinese Journal of Chemical Engineering 2018年第3期26卷 593-600页

作者： Yaseen Muhammad Ayesha Shoukat Ata ur Rahman Haroon ur Rashid Waqas Ahmad Institute of Chemical Sciences University ofPeshawar Khyber Pakhtunkhwa Pakistan School of Chemistry and Chemical Engineering Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology Guangxi University Guangxi 530004 China Department of Chemistry 5arhad University of Science and Information Technology Peshawar Pakistan

This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al2O3 catalysts in the oxidative desulfurization （ODS） of dibenzothiophene （DBT） using H2O2 and formic acid as oxidants. The influence of operating parameters i.e. reaction time, catalyst dose, reaction temperature and oxidant amount on oxidation process was investigated. Results revealed that 99% DBT conversion was achieved at 60℃ and 150 min reaction time over Fe-Ni-Mo/Al2O3. Fe tremendously enhanced the ODS activity of Co or Ni based Mo/Al2O3 catalysts following the activity order：Fe-Ni-Mo/Al2O3 〉 Fe-Co-Mo/Al2O3 〉 Ni-Mo/Al2O3 〉 Co-Mo/Al2O3, while H2O2 exhibited higher oxidation activity than formic acid over all catalyst systems. Insight about the surface morphology and textural properties of fresh and spent catalysts were achieved using scanning electron microscopy （SEM）, X-ray diffraction （XRD）, energy dispersive X-ray （EDX） analysis, Atomic Absorption Spectroscopy （AAS） and BET surface area analysis, which helped in the interpretation of experimental data. The present study can be deemed as an effective approach on industrial level for ODS of fuel oils crediting to its high efficiency, low process/catalyst cost, safety and mild operating condition.

关键词： Oxidative desulfurization Fuel oil Dibenzothiophene Fe promoted (Co/Ni)-Mo/Al2O3 catalyst XRD

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Supergravity-induced interactions on thick branes

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Chinese Physics B 2014年第4期23卷 135-146页

作者： Nejat T.yilmaz Department of Electrical and Electronics Engineering Yassar UniversitySelsuk Yassar Kampüsü niversite CaddesiNo:35-37 AgaliYol35100 Bornova zmir Turkey

The gravity coupling of the symmetric space sigma model is studied in the solvable Lie algebra parametrization. The corresponding Einstein equations are derived and the energy-momentum tensor is calculated. The results are used to derive the dynamical equations of the warped five-dimensional （5D） geometry for localized bulk scalar interactions in the framework of thick brane world models. The Einstein and scalar field equations are derived for flat brane geometry in the context of minimal and non-minimal gravity-bulk scalar couplings.

关键词： supergravity branes 5D warped geometry symmetric spaces

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Gender disparities and woman-specific trends in Barrett’s esophagus in the united States:An 11-year nationwide populationbased study

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World Journal of Methodology 2025年第1期15卷 60-71页

作者： Karina Fatakhova Faisal Inayat Hassam Ali Pratik Patel Attiq ur Rehman Arslan Afzal Muhammad Sarfraz Shiza Sarfraz Gul Nawaz Ahtshamullah Chaudhry Rubaid Dhillon Arthur Dilibe Benjamin Glazebnik Lindsey Jones Emily Glazer Division of Gastroenterology and Hepatology Mather Hospital and Zucker School of Medicine at Hofstra UniversityPort JeffersonNY 11777United States Department of Internal Medicine Allama Iqbal Medical CollegeLahorePunjab 54550Pakistan Division of Gastroenterology and Hepatology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Division of Gastroenterology and Hepatology Geisinger Wyoming Valley Medical CenterWilkes-BarrePA 18711United States Department of Internal Medicine East Carolina University Brody School of MedicineGreenvilleNC 27834United States Department of Internal Medicine St.Dominic's HospitalJacksonMS 39216United States Department of Gastroenterology Hepatologyand NutritionCleveland Clinic FoundationClevelandOH 44195United States Department of Internal Medicine Mather Hospital and Hofstra University ZuckerSchool of MedicinePort JeffersonNY 11777United States

BACKGROuND Barrett's esophagus(BE)is a known premalignant precursor to esophageal adenocarcinoma(EAC).The prevalence rates continue to rise in the united States,but many patients who are at risk of EAC are not *** practice guidelines include male gender as a predisposing factor for BE and *** population-based clinical evidence regarding female gender remains *** To study comparative trends of gender disparities in patients with BE in the united *** A nationwide retrospective study was conducted using the 2009-2019 National Inpatient Sample(NIS)*** with a primary or secondary diagnosis code of BE were *** major outcome of interest was determining the gender disparities in patients with *** analysis for respective outcomes for females was also reported to ascertain any time-based *** We identified 1204190 patients with BE for the study *** the included patients,717439(59.6%)were men and 486751(40.4%)were *** mean age was higher in women than in men(67.1±0.4 vs 66.6±0.3 years,Puency of obesity among women compared to men(17.4%vs 12.6%,Puse,Helicobacter pylori(***),and diabetes mellitus among females than males(Puse disorder and a decreasing prevalence of *** and diabetes mellitus among women(PuSION The prevalence of BE among

关键词： Barrett’s esophagus Gender disparity Epidemiological trends Esophageal adenocarcinoma Screening endoscopy Female gender Risk factors

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Investigation of ZrO2 nanoparticles concentration and processing time effect on the localized PEO coatings formed on AZ91 alloy

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Journal of Magnesium and Alloys 2019年第4期7卷 555-565页

作者： Zeeshan ur Rehman Dongjin Choi School of Materials Science and Engineering Hongik UniversitySejongRepublic of Korea

AZ91 Mg alloy was treated through a new localized PEO(Plasma Electrolytic Oxidation)coating approach,using electrolyte solutions with varying ZrO2 nanoparticles concentration(2-8 g/L)and processing *** increase in the ZrO2 concentration,several microstructural changes were observed including;formation of cluster-type structure,damage to the inner layers(∼30 min)and sealing of *** analysis of the final coatings was carried out using potentiodynamic polarization,electrochemical impedance spectroscopy and post-corrosion *** was explored that highest corrosion resistance(Rp∼81.17 kΩcm^2)of the coatings was obtained for ZrO2∼2 g/***,higher concentration of the ZrO2 nanoparticles caused weak crystalline coating structure,due to unstable and lower intensity discharges,thus failed to offer high corrosion resistance performance.

关键词： Magnesium alloy PEO coating ZrO2 Corrosion Nanoparticles addition

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