36 research outputs found

    Magnetic Nanoparticles for Plasmid DNA Adsorption via Hydrophobic Interaction

    Get PDF
    This study aims the preparation of magnetic poly(2-hydroxyethylmethacrylate-N-methacryloyl-Lphenylalanine), [poly(HEMA-MAPA)] nanoparticles for plasmid DNA separation on the basis of hydrophobic interactions. Magnetic nanoparticles will be produced emulsion polymerization of 2- hydroxyethylmethacrylate (HEMA) and N-methacryloyl-L-phenylalanine (MAPA) monomers. Nanosized particles including hydrophobic groups stemmed from polymerizable derivative of phenylalanine aminoacid were evaluated to offer surface area that is enough for the higher capacity DNA purification than commercial micronsized sorbents for DNA purification. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3494

    Effect of Si on austenite stabilization, martensite morphology, and magnetic properties in Fe-26%Ni-x%Si alloys

    No full text
    WOS: 000289033900011The effect of Si on the austenite stabilization, martensite morphology, and magnetic properties in Fe-26%Ni-x%Si (x=3.5, 5, and 6) alloys have been studied by means of transmission electron microscopy (TEM) and Mossbauer spectroscopy techniques. TEM observations reveal that the martensite morphology is closely dependent on the Si content. The volume fraction changes of martensite and austenite phases, the hyperfine magnetic field, and isomer shift values have been determined by Mossbauer spectroscopy. The Mossbauer study reveals that the hyperfine magnetic field, the isomer shift values and the volume fraction of martensite decrease with increasing Si content.Kirikkale UniversityKirikkale University [2006/15]This work was financially supported by the Research Fund of Kirikkale University (No.2006/15

    The effect of austenitizing time on martensite morphologies and magnetic properties of martensite in Fe-24.5%Ni-4.5%Si alloy

    No full text
    WOS: 000247934600029The effect of austenitizing time on the formation of martensite in Fe-24.5%Ni-4.5%Si alloy has been studied by means of transmission electronmicroscope (TEM), scanning electronmicroscope (SEM) and Mossbauer spectroscopy technique. TEM and SEM observations revealed that the martensite morphology was found to be closely dependent on the austenitizing time. The orientation relationship between austenite and thermally induced martensite was found as the Kurdjumov-Sachs type. The volume fraction changes of martensite and austenite phases, the hyperfine magnetic field of martensite phase and isomery shift values have been determined by Mossbauer spectroscopy. The Mossbauer study also revealed that the martensite volume fractions increased with increasing austenite grain size

    Effect of medications for root canal treatment on bonding to root canal dentin

    No full text
    Erdemir, Ali/0000-0002-6489-9620; Erdemir, Ali/0000-0003-1140-3887WOS: 000188700300013PubMed: 14977310Use of resin-based restorative materials recently has become widely accepted for treatment of endodontically treated teeth. However, some solutions routinely used during endodontic treatment procedures may have an effect on bond strengths of adhesive materials to root canal dentin. The purpose of this in vitro study was to evaluate the effect of various medications on microtensile bond strength to root canal dentin. Fourteen extracted human single-rooted teeth were used. The crowns and the pulp tissues were removed. The root canals were then instrumented and widened to the same size. The teeth were randomly divided into seven groups of two teeth each. The root canal dentin walls of the roots were treated with 5% sodium hypochloride (NaOCl), 3% hydrogen peroxide (H2O2), the combination of H2O2 and NaOCl, or 0.2% chlorhexidine gluconate for 60 s; or calcium hydroxide or formocresol for 24 h. The teeth in control group were irrigated with water. The root canals were obturated using C&B Metabond. After 24 h of storage in distilled water,serial 1-mm-thick cross-sections were cut, and approximately 12 samples were obtained from each group. Microtensile bond strengths to root canal dentin were then measured by using an Instron machine. The data were recorded and expressed as MPa. The results indicated that NaOCl, H2O2, or a combination of NaOCl and H2O2 treatment decreased bond strength to root canal dentin significantly (p < 0.05). The teeth treated with chlorhexidine solution showed the highest bond strength values (p < 0.05). In conclusion, chlorhexidine is an appropriate irrigant solution for root canal treatment before adhesive post core applications

    Mossbauer studies on athermal martensite formation in an Fe-Ni-Mn alloy

    No full text
    WOS: 000178494300001In this study, austenite-martensite phase transformations which are formed by cooling effect in Fe-30% Ni-0.2% Mn alloy are investigated with Mossbauer spectroscopy and scanning electron microscopy. The single peak of the paramagnetic phase and the six peaks of the ferromagnetic phase of Fe-30% Ni-0.2% Mn alloy were observed in the Mossbauer spectrum. The internal magnetic field strength of ferromagnetic martensite phase was. determined as 33.8 T and the isomer shift values were determined as - 0.11 mm(.)sec(-1) and - 0.06 mm.sec(-1), respectively, for the austenite and martensite phases. In this alloy, athermal transformation was observed. The results obtained are in agreement with literature

    Effect of Mo on the magnetic properties of martensitic phase in Fe-Ni-Mo alloys

    No full text
    WOS: 000241414900012The paramagnetic-magnetically ordered transition and the effect of Mo content on the magnetic properties of martensite phase in Fe-30% Ni-x% Mo alloys have been investigated by AC susceptibility and Mossbauer spectroscopy. The results show that martensitic transformation temperature (M(S)) indicates the magnetic transition from paramagnetic to magnetically ordered state. Hyperfine magnetic field, isomery shift and volume fractions of phases were determined by Mossbauer spectroscopy. It is also found that volume fraction of thermally induced martensite and M(S) temperature decreased with the increasing Mo content. (c) 2006 Elsevier B.V. All rights reserved

    Some characteristics of thermally induced martensite in Fe-30%Ni-3.6%Mo alloy

    No full text
    WOS: 000255429900015Kinetical, morphological and magnetic characteristics of thermally induced martensite in an Fe-30%Ni-3.6%Mo alloy has been studied by scanning electron microscopy, transmission electron microscopy and Mossbauer spectroscopy. Scanning electron microscope and transmission electron microscope observations revealed the occurrence of both athermal and isothermal martensitic transformation in the alloy. In addition, the magnetic properties of both the austenite and martensite phases were determined by the Mossbauer spectroscopy. The Mossbauer spectra showed a paramagnetic character for the austenite phase and an antiferromagnetic character for the martensite phase. (C) 2007 Elsevier Inc. All rights reserved

    New observations on the formation of athermal martensite in Fe-Ni-Mo alloys

    No full text
    WOS: 000243736200022The thermally induced gamma-epsilon and gamma-alpha' martensitic transformation in Fe-30%Ni-x%Mo alloys with different Mo contents have been studied by transmission electron microscopy (TEM). Observations reveal that alpha' martensite is found in alloys containing 0.8, 1.8, and 2.6% Mo, and 8 martensite in the alloy containing 5%Mo. The first three display the Kurdjumov-Sachs (K-S) orientation relationship between gamma and alpha', while the other displays the Shoji-Nishiyama (S-N) orientation relationship between gamma and epsilon. (c) 2006 Elsevier B.V. All rights reserved

    Oleylamine surface functionalized FeCoyFe2-yO4 (0.0 <= y <= 1.0) nanoparticles

    No full text
    In this study, oleylamine (OAm) capped FeCoyFe2-yO4 (0.0 <= y <= 1.0) nanocomposites (NCs) were prepared via a polyol route. Effect of Co3+ ion substitution on structure, morphology and magnetic properties of Fe3O4 nanoparticles was investigated by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analyzer (TGA), scanning and transmission electron spectroscopy (SEM and TEM), vibrating sample magnetometer (VSM) and Mossbauer analyzer. All XRD patterns show the single phase spinel ferrite without any impurity. The crystallite size of the samples is within the range of 7.1-21.7 nm. FT-IR analysis showed that all products were successfully packed by OAm. Both SEM and TEM results confirmed that products have spherical morphology with small agglomeration. When Co3+ ions were substituted to the Fe3O4, Ms continued to decrease up to Co3+ content of y = 0.4. It was reported that Co3+ ions prefer to replace Fe2+ ions on octahedral side up to some concentration. Although the Mossbauer spectra for the all samples were composed of magnetic sextets, superparamagnetic particles are also formed for FeCo0.6Fe1.4O4, FeCo0.8Fe1.2O4 and FeCoFe2O4 samples. (C) 2016 Production and hosting by Elsevier B.V. on behalf of King Saud University

    Martensitic transformation and magnetic properties of Fe-24.5%Ni-4.5%Si alloy

    No full text
    WOS: 000249842400014The effect of austenitising temperature and cooling rate on the morphology and magnetic properties of martensite in Fe-24-5%Ni-4-5%Si alloy has been studied by means of scanning electron microscopy, Mbssbauer spectroscopy and AC susceptibility. Martensite morphology was found to be closely dependent on the austenitising temperature and cooling rate. The changes in volume fraction of martensite and austenite phases, the internal magnetic field of martensite phase and the isomery shift values have been determined by Mbssbauer spectroscopy. The Mbssbauer study revealed that the martensite volume fractions increased with increasing austenitising temperature and cooling rate. Also internal magnetic field of martensite was decreased by increasing the martensite volume fractions. AC magnetic susceptibility measurements showed that the Neel temperatures T-N and the magnetic susceptibility X increase with increasing austenitising temperatures
    corecore