Rare earth(RE)doped ferrites with the chemical formula Cu_(0.3)Zn_(0.3)Mg_(0.4)T_(x)Fe_(2-x)O_(4)(x=0,0.1;T=La,Ce,Sr)were synthesized by chemical co-precipitation method.The structural,optical,electrical and humidity ...Rare earth(RE)doped ferrites with the chemical formula Cu_(0.3)Zn_(0.3)Mg_(0.4)T_(x)Fe_(2-x)O_(4)(x=0,0.1;T=La,Ce,Sr)were synthesized by chemical co-precipitation method.The structural,optical,electrical and humidity sensing properties of Cu-Mg-Zn ferrites with rare earth element doping were investigated.Single-phase cubic spinel structure was confirmed via X-ray diffraction(XRD),and the crystal size ranges fro m 22.12 to 63.17 nm according to the Scherrer formula and from 25.66 to 67.46 nm according to the Williamson-Hall method.Po rous structure and elemental characterization of the samples were investigated by scanning electron microscopy(SEM).The optic band gap varies between 2.21 and 2.49 eV.Electrical measurements were conducted in the frequency range of 1 Hz-20 MHz and temperature range of 25-400℃.It has been determined that the dielectric results are consistent with the Maxwell-Wagner method and exhibit a non-Debye relaxation model,as observed from the Nyquist plots.At a minimum frequency value of 1 Hz,the dielectric constants for pure,Ce,Sr,and La samples are 9×10^(4),5×10^(4),1×10^(8),and 2×10^(5) at 25℃,and 1.85×10^(8),1.34×10^(8),1.15×10^(10),and 4.4×10^(8)at 400℃.In the same order,for the maximum frequency value of 20 MHz,the dielectric constants at 25℃are 169,166,3799,and 60,while at 400℃they are 734,624,12108,and 774.The La doped sample's low dielectric loss makes it suitable for high-frequency applications.Humidity measurements were performed at room temperature and in the 5%-95%relative humidity range.The humidity properties of the samples were investigated through humidity mapping,sensitivity,hysteresis,and long-term stability tests.Compared to other samples,the results indicate that Ce exhibits better humidity performance with 99%sensitivity and the highest repeatability(91.2%).These results show that Ce-doped ferrite can be used as a low-cost,high-performance humidity sensor.展开更多
Objective:To investigate the molecular effects ofNerium oleanderleaf distillate on paclitaxel and vincristine resistant(MCF-7/Pac and MCF-7/Vinc)cells and sensitive(MCF-7/S)cell lines.Methods:Nerium oleander(N.oleande...Objective:To investigate the molecular effects ofNerium oleanderleaf distillate on paclitaxel and vincristine resistant(MCF-7/Pac and MCF-7/Vinc)cells and sensitive(MCF-7/S)cell lines.Methods:Nerium oleander(N.oleander)leaf extract was obtained by hydrodistillation method.The toxicological effects ofN.oleanderdistillate,previously suggested as medicinal food supplement,on drug resistant cells were evaluated by XTT tests.MDR modulation potential of the plant material was evaluated by flow cytometry and fluorescent microscopy.Paclitaxel and vincristine were applied to the sublines in combination with N.oleanderdistillate.Results:Fractional inhibitory indices show thatN.oleanderdistillate did not increase the antiproliferative effects of anticancer drugs.N.oleandertreatment in to MCF-7/Pac and MCF-7/Vinc did not inhibit P-gp activity and MDR1 gene expression level.Conclusions:As a result it may be suggested that althoughN.oleanderdistillate has some medicinal effects as food supplement it may not be suitable as an MDR modulator for drug resistant breast cancer cells.展开更多
This paper presents the plasma polymerization of poly（hexafluorobutyl acrylate）（PHFBA） thin films on different substrates in an RF plasma reactor with an outer planar electrode. This reactor configuration allows？...This paper presents the plasma polymerization of poly（hexafluorobutyl acrylate）（PHFBA） thin films on different substrates in an RF plasma reactor with an outer planar electrode. This reactor configuration allows？large area uniformity and fast processing times. Deposition rates of up to60 nm min-1were observed. The influence？of plasma power and substrate temperature on the？deposition rate, structure and wettability of the as-deposited films was？investigated. It was observed that better hydrophobicity was obtained at high plasma power and in low temperature conditions. PHFBA thin films deposited on electrospun poly（acrylonitrile） fiber mats under such conditions resulted in superhydrophobic surfaces with？contact angle values greater than 150°.In？vitro cell studies using human epithelial cells demonstrated the non-toxic nature of the？plasma-polymerized PHFBA films.展开更多
基金supported by the Ondokuz Mayis University Project Number PYO.MUH.1901.21.001。
文摘Rare earth(RE)doped ferrites with the chemical formula Cu_(0.3)Zn_(0.3)Mg_(0.4)T_(x)Fe_(2-x)O_(4)(x=0,0.1;T=La,Ce,Sr)were synthesized by chemical co-precipitation method.The structural,optical,electrical and humidity sensing properties of Cu-Mg-Zn ferrites with rare earth element doping were investigated.Single-phase cubic spinel structure was confirmed via X-ray diffraction(XRD),and the crystal size ranges fro m 22.12 to 63.17 nm according to the Scherrer formula and from 25.66 to 67.46 nm according to the Williamson-Hall method.Po rous structure and elemental characterization of the samples were investigated by scanning electron microscopy(SEM).The optic band gap varies between 2.21 and 2.49 eV.Electrical measurements were conducted in the frequency range of 1 Hz-20 MHz and temperature range of 25-400℃.It has been determined that the dielectric results are consistent with the Maxwell-Wagner method and exhibit a non-Debye relaxation model,as observed from the Nyquist plots.At a minimum frequency value of 1 Hz,the dielectric constants for pure,Ce,Sr,and La samples are 9×10^(4),5×10^(4),1×10^(8),and 2×10^(5) at 25℃,and 1.85×10^(8),1.34×10^(8),1.15×10^(10),and 4.4×10^(8)at 400℃.In the same order,for the maximum frequency value of 20 MHz,the dielectric constants at 25℃are 169,166,3799,and 60,while at 400℃they are 734,624,12108,and 774.The La doped sample's low dielectric loss makes it suitable for high-frequency applications.Humidity measurements were performed at room temperature and in the 5%-95%relative humidity range.The humidity properties of the samples were investigated through humidity mapping,sensitivity,hysteresis,and long-term stability tests.Compared to other samples,the results indicate that Ce exhibits better humidity performance with 99%sensitivity and the highest repeatability(91.2%).These results show that Ce-doped ferrite can be used as a low-cost,high-performance humidity sensor.
基金Supported by TUBITAK with the project number 111S039by the Selcuk University Research Fund with the project number 11401014
文摘Objective:To investigate the molecular effects ofNerium oleanderleaf distillate on paclitaxel and vincristine resistant(MCF-7/Pac and MCF-7/Vinc)cells and sensitive(MCF-7/S)cell lines.Methods:Nerium oleander(N.oleander)leaf extract was obtained by hydrodistillation method.The toxicological effects ofN.oleanderdistillate,previously suggested as medicinal food supplement,on drug resistant cells were evaluated by XTT tests.MDR modulation potential of the plant material was evaluated by flow cytometry and fluorescent microscopy.Paclitaxel and vincristine were applied to the sublines in combination with N.oleanderdistillate.Results:Fractional inhibitory indices show thatN.oleanderdistillate did not increase the antiproliferative effects of anticancer drugs.N.oleandertreatment in to MCF-7/Pac and MCF-7/Vinc did not inhibit P-gp activity and MDR1 gene expression level.Conclusions:As a result it may be suggested that althoughN.oleanderdistillate has some medicinal effects as food supplement it may not be suitable as an MDR modulator for drug resistant breast cancer cells.
基金supported by the Scientific and Technological Research Council of Turkey(TüBITAK)with grant number 213M399supported by TüBITAK-BIDEB
文摘This paper presents the plasma polymerization of poly（hexafluorobutyl acrylate）（PHFBA） thin films on different substrates in an RF plasma reactor with an outer planar electrode. This reactor configuration allows？large area uniformity and fast processing times. Deposition rates of up to60 nm min-1were observed. The influence？of plasma power and substrate temperature on the？deposition rate, structure and wettability of the as-deposited films was？investigated. It was observed that better hydrophobicity was obtained at high plasma power and in low temperature conditions. PHFBA thin films deposited on electrospun poly（acrylonitrile） fiber mats under such conditions resulted in superhydrophobic surfaces with？contact angle values greater than 150°.In？vitro cell studies using human epithelial cells demonstrated the non-toxic nature of the？plasma-polymerized PHFBA films.
