Person: TEMEL, BİNNUR
Now showing 1 - 10 of 52
- PublicationMetadata onlyPhotoinduced Electron Transfer Reactions of Highly Conjugated Thiophenes for Initiation of Cationic Polymerization and Conjugated Polymer Formation(2012-10-09T00:00:00Z) Aydogan, BİNNUR; Yağcı, Yusuf; Toppare, Levent; Jockusch, Steffen; Turro, Nicholas J.; TEMEL, BİNNURPhotoinduced electron transfer reactions of highly conjugated thiophene derivatives, 4,7-di(2,3-dihydrothieno[3,4-b] [1,4]dioxin-5-yl)benzo[1,2,5]thiadiazole (DTDT) and 5,8-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2,3-di(thiophen-2-yl)quinoxaline (DTDQ), with diphenyl-iodonium hexafluorophosphate (Ph2I+PF6-) and triphenylsulfonium hexafluorophosphate (Ph3S+PF6-) were investigated by laser flash photolysis, fluorescence and phosphorescence spectroscopy, and polymerization studies. High fluorescence quantum yields, long fluorescence lifetimes (similar to 10 ns in aprotic solvents), and absence of detectable phosphorescence at 77 K for both compounds indicate inefficient intersystem crossing into the triplet state and dominant role of singlet excited state. Photolysis of DTDT or DTDQ in the presence of iodonium salt with visible light results in the formation of radical cations of DTDT and DTDQ as detected by laser flash photolysis. Sulfonium salts do not undergo such electron transfer reactions due to the unfavorable redox potentials. The importance of the described photoinduced electron transfer process with respect to the initiation of cationic polymerization and formation of conjugated polymers was demonstrated.
- PublicationMetadata onlyAcademicians Perspective for the Application Requirements to the Graduate Programs, Education and Functioning of the Institute of Health Sciences in Bezmialem Vakif University(2018-05-26) ÖZÇELİK, SEMRA; TEMEL, BİNNUR; ÖZÇELİK, SEMRA; TEMEL, BİNNUR
- PublicationMetadata onlySynthesis, characterization and thermally activated curing of polysulfones with benzoxazine end groups(2011-03-23T00:00:00Z) Ates, Sahin; Dizman, Cemil; Aydogan, BİNNUR; KISKAN, Bans; TORUN, Lokman; Yağcı, Yusuf; TEMEL, BİNNURPolysulfones with benzoxazine end groups (PSU-B-a) were obtained using monomer synthesis method from the phenol terminated polysulfone (PSU-OH), aniline and paraformaldehyde as starting materials. For this purpose, the precursor PSU-OHs with different molecular weights were prepared by condensation of bisphenol-A and bis(p-chlorophenyl) sulfone in presence of potassium carbonate. The structure of the polymers before and after functionalization was confirmed by proton nuclear magnetic resonance spectroscopy (H-1 NMR) and Fourier transform infrared spectroscopy (FT-IR). Thermally activated crosslinking behavior of these polymers was investigated by differential scanning calorimetry (DSC). Thermal and tensile properties of the crosslinked polymers obtained from PSU-B-a alone or with low molar mass benzoxazine (P-a) were studied by thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). (C) 2011 Elsevier Ltd. All rights reserved.
- PublicationMetadata onlyBir Üniversitenin Girişimsel Olmayan Araştırmalar Etik Kuruluna Yapılan Başvurularda Eksiklikler ve Sıklıkla Yapılan Hatalar(2019-08-01) Meral, İsmail; Aştı, Türkinaz; Soysal, Ömer; Yıldırım, Nuran; Özçelik, Semra; Aydın, Teoman; Akbaş, Fahri; Temel, Binnur; Özder, Aclan; Büyükpınarbaşılı, Nur; Dönmez, Nazmiye; Alkaya, Mustafa Fırat; MERAL, İSMAİL; AŞTI, TÜRKINAZ; SOYSAL, ÖMER; YILDIRIM, NURAN; ÖZÇELİK, SEMRA; AYDIN, TEOMAN; AKBAŞ, FAHRİ; TEMEL, BİNNUR; ÖZDER, ACLAN; BÜYÜKPINARBAŞILI, NUR; DÖNMEZ, NAZMİYEGirişimsel olmayan araştırmalarda, ilgili etik kurulun onayını almadan çalışmalara başlamak mümkün değildir. Dünya Sağlık Örgütü-nün kurallarına göre, gerekli tüm belgeleri içeren başvuru dosyası ilgili Etik Kurula eksiksiz sunulmalıdır. Araştırmacıların başvuru dosyasındaki belgeleri eksiksiz tamamlamadaki isteksizliği, Etik Kurulların çalışma sürecini yavaşlatmakta ve hatta Etik Kurul ile araştırmacılar arasında tartışmaya bile neden olabilmektedir. Bu nedenle bu çalışma, bir üniversitenin Girişimsel Olmayan Araştırmalar Etik Kuruluna gönderilen proje başvuru dosyalarındaki eksiklikleri ve en çok yapılan hataları göstermek ve araştırmacılar için bir rehber oluşturmak amacıyla yapıldı. 24 Mart 2016 ve 30 Haziran 2018 tarihleri arasında Girişimsel Olmayan Araştırmalar Etik Kurula gönderilen başvuru dosyaları ve kararları ilgili etik kurulun veri tabanından analiz edildi. Başvuru dosyalarının revizyonuna neden olan en önemli gerekçeler, projenin amacının ilgili referanslar eşliğinde yeterince açıklanamaması ve özellikle iyi yazılamamış yöntem kısmı gibi başvuru formundaki eksikliklerdi. Araştırmacıları proje başvuru dosyası hazırlarken en çok yapılan hatalar hakkında eğitmek, Üniversite Etik Kurullarının gözden geçirme sürecinin verimliliğini ve hızını artıracaktır.
- PublicationMetadata onlyThioxanthone-Fluorenes as Visible Light Photoinitiators for Free Radical Polymerization(2010-05-25T00:00:00Z) Yilmaz, Gorkem; Aydogan, Binnur; Temel, Gokhan; ARSU, Nergis; MOSZNER, Norbert; Yağcı, Yusuf; TEMEL, BİNNURTwo thioxanthone derivatives with fluorene additional chromophoric groups, namely thioxanthone-fluorenecarboxylie acid (TX-FLCOOH) and thioxanthone fluorene sodium carboxylate (TX-FLCOONa), as visible light absorbing oil- and water-soluble photoinitiators, respectively, were synthesized and characterized. Their ability to initiate photopolymerization of methyl methacrylate (M MA), 2-(2-phosphonoethoxymethyl)acrylic acid ethyl ester (EAEPA), and a multifunctional monomer, trimethylolpropane triacrylate (TMPTA), were examined. The initiation efficiency of TX-FLCOOH was compared with the parent thioxantone (TX) both in the presence and in the absence of a co-initiator, and TX-FLCOOH was found to be more effective in :ill cases. Photopolymerization and laser flash photolysis studies revealed that depending on the concentration initiation by TX-FLCOOH occurs by intra and intermolecular H-abstraction of the triplet (3)(TX-FLCOOH)*. No polymerization was observed when TX-FLCOONa was used as photoinitiator in the absence of a co-initiator. However, TX-FLCOONa acts as an efficient initiator in the visible range in the presence of H donors in water.
- PublicationMetadata onlySingle-chainpolymer nanoparticles via click crosslinking and effect of photoinduced radical combination on crosslink points(2020-07-01T00:00:00Z) Keklik, Merve; Akar, Irem; Temel, BİNNUR; Balta, Demet Karaca; Temel, Gokhan; TEMEL, BİNNURFolding of azide functionalized polymer chains was obtained via the copper-catalyzed azide alkyne cycloaddition (CuAAC) methodology using a light-responsive crosslinker as the -click- component. Subsequently, crosslinked junction points were combined with a photoinduced radical combination strategy to achieve more compact nanoparticles. The resultant folding particles possess smaller particle sizes and higher glass transition temperature values compared to their linear analogues. Fourier transform IR spectroscopy, SEC, DSC, dynamic light scattering,H-1 NMR and TEM techniques were used for characterization. (c) 2020 Society of Chemical Industry
- PublicationMetadata onlyGenetic disruption of nucleoside transporter 4 reveals its critical roles in malaria parasite sporozoite functions.(2022-08-24T00:00:00Z) Deveci, GÖZDE; Kamil, Mohd; Kina, Umit; Temel, Binnur Aydogan; Aly, Ahmed S I; DEVECİ, GÖZDE; KAMIL, MOHD; KINA, ÜMİT YAŞAR; TEMEL, BİNNUR
- PublicationMetadata onlyThermally curable main-chain benzoxazine prepolymers via polycondensation route(2013-02-01T00:00:00Z) Demir, Kubra Dogan; Kışkan, Barış; Aydogan, BİNNUR; Yağcı, Yusuf; TEMEL, BİNNURPolybenzoxazines are addition-cure thermosetting polymers exhibiting versatility in a wide range of applications due to their good mechanical properties, dimensional stability, chemical resistivity, flame resistance property phenolic or epoxy resins have myriad applications in diverse fields starting from commodity materials to high technology aerospace industries. In this paper, we present synthetic strategies to incorporate thermally curable benzoxazine functionality into polymers as main-chain fashion in order to further improve various properties. The strategies successfully employed including monomer synthesis and polycondensation routes like Mannich reaction, click chemistry, hydrosilylations, and coupling reactions. The structure-property relationships of the cured materials have also been presented and discussed. (C) 2012 Elsevier Ltd. All rights reserved.
- PublicationMetadata onlyLong wavelength photoinitiated free radical polymerization using conjugated thiophene derivatives in the presence of onium salts(2011-01-01T00:00:00Z) Beyazit, Selim; Aydogan, BİNNUR; Osken, Ipek; Öztürk, Turan; Yağcı, Yusuf; TEMEL, BİNNURLong wavelength free radical photopolymerization of (meth) acrylic monomers using a conjugated thiophene derivative, namely 3,5-diphenyldithieno[3,2-b: 2-,3--d]-thiophene (DDT) and one of the following compounds, namely diphenyliodonium hexafluorophosphate (Ph(2)I(+)PF(6)(-)), triphenylsulfonium hexafluorophosphate (Ph(3)S(+)PF(6)(-)) and N-ethoxy-2-methylpyridinium hexafluorophosphate (EMP(+)PF(6)(-)), as photosensitizer and coinitiator, respectively, was described. Polymerization occurred only when DDT, in the presence of the onium salts, was irradiated at wavelengths where the salts have no absorption. A feasible initiation mechanism involves intermolecular electron transfer from photoexcited thiophene compound to the onium salt. The relative initiation efficiencies of the salts were investigated and evaluated in terms of their redox potentials.
- PublicationMetadata onlySingle Dose Mixed Species Malaria Vaccination of Genetically Attenuated Blood Stage Malaria Parasites Induce Sterile Immunity Against Lethal Challenge by Both Species(2021-09-13T00:00:00Z) Deveci, Gözde; Temel, Binnur; Aly, Ahmed Sayed Ibrahım; DEVECİ, GÖZDE; TEMEL, BİNNUR; ALY, AHMED SAYED IBRAHıM