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Noraini Nordin Samikannu Kanagesan Nur Rizi Zamberi Swee Keong Yeap Nadiah Abu Subramani Tamilselvan Mansor Hashim Noorjahan Banu Alitheen 《IET nanobiotechnology / IET》2017,11(3):343
In this study, nanocrystalline magnesium zinc ferrite nanoparticles were successfully prepared by a simple sol–gel method using copper nitrate and ferric nitrate as raw materials. The calcined samples were characterised by differential thermal analysis/thermogravimetric analysis, Fourier transform infrared spectroscopy and X‐ray diffraction. Transmission electron microscopy revealed that the average particle size of the calcined sample was in a range of 17–41 nm with an average of 29 nm and has spherical size. A cytotoxicity test was performed on human breast cancer cells (MDA MB‐231) and (MCF‐7) at various concentrations starting from (0 µg/ml) to (800 µg/ml). The sample possessed a mild toxic effect toward MDA MB‐231 and MCF‐7 after being examined with MTT (3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5 diphenyltetrazolium bromide) assay for up to 72 h of incubation. Higher reduction of cells viability was observed as the concentration of sample was increased in MDA MB‐231 cell line than in MCF‐7. Therefore, further cytotoxicity tests were performed on MDA MB‐231 cell line.Inspec keywords: sol‐gel processing, nanoparticles, nanofabrication, magnesium compounds, zinc compounds, toxicology, biological organs, cancer, cellular biophysics, nanomedicine, calcination, differential thermal analysis, Fourier transform infrared spectra, X‐ray diffraction, transmission electron microscopy, particle size, organic compoundsOther keywords: sol‐gel method, cytotoxic effects, breast cancer cell line, MDA MB‐231 in vitro, nanocrystalline magnesium zinc ferrite nanoparticles, copper nitrate, ferric nitrate, raw materials, calcined samples, differential thermal analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, average particle size, cytotoxicity testing, human breast cancer cells, mild toxic effect, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyltetrazolium bromide) assay, cell viability, MCF‐7, MDA MB‐231 cell line, size 17 nm to 41 nm 相似文献
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K. Senthilkumar T. Kalaivani S. Kanagesan V. Balasubramanian 《Journal of Materials Science: Materials in Electronics》2012,23(11):2048-2052
ZnSe QDs have been synthesized by wet chemical, template free process by zinc acetate and elemental selenium powder in presence of ethylene glycol, hydrazine hydrate and a defined amount of water at 90 °C. The product was in strong quantum confinement regime, having yield as high as 50 %. The transmission electron microscopy image indicated that the particles were well dispersed and spherical in shape. The X-ray diffraction analysis showed that the ZnSe nanoparticles were of the Cubic structure, with average particle diameter of about 3.50 nm. The FTIR characteristic indicates that the N2H4 molecule has intercalated into the complex and formed a molecular precursor. 相似文献
4.
The identification of brain tumors is multifarious work for the separation of the
similar intensity pixels from their surrounding neighbours. The detection of tumors is
performed with the help of automatic computing technique as presented in the proposed
work. The non-active cells in brain region are known to be benign and they will never
cause the death of the patient. These non-active cells follow a uniform pattern in brain and
have lower density than the surrounding pixels. The Magnetic Resonance (MR) image
contrast is improved by the cost map construction technique. The deep learning algorithm
for differentiating the normal brain MRI images from glioma cases is implemented in the
proposed method. This technique permits to extract the linear features from the brain MR
image and glioma tumors are detected based on these extracted features. Using k-mean
clustering algorithm the tumor regions in glioma are classified. The proposed algorithm
provides high sensitivity, specificity and tumor segmentation accuracy. 相似文献
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S. Jesurani S. Kanagesan T. Kalaivani K. Ashok 《Journal of Materials Science: Materials in Electronics》2012,23(3):692-696
The dielectric properties of Erbium doped CaCu3Ti(4–x)ErxO(12–δ) with x = 0, 0.05, 0.1 were synthesized by the sol–gel self combustion method. XRD (X-ray powder diffraction) analysis confirmed
the formation of single-phase material in the samples calcined at 800 °C. Crystal structure does not change on doping with
Erbium and it remains cubic in all the three compositions studied. It is found that lattice parameter increases slightly with
Erbium doping. The surface morphology of CaCu3Ti(4–x)ErxO(12–δ) powders sintered at 950 °C in air for 3 h was observed using high resolution—scanning electron microscope and it shows that
the grain size is in the range of 1–8 μm for these samples. Energy dispersive X-ray spectroscopy pattern confirmed the presence
of Erbium with 1.9 and 4.86 atomic percentages with doping concentration. The dielectric characteristics of CaCu3Ti(4–x)ErxO(12–δ) were studied by LCR meter in the frequency range (100 Hz–1 MHz) at various temperatures (RT to 500 °C). Interestingly, the
dielectric constant increases and dielectric loss had lower values than those of undoped CCTO. 相似文献
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S. Kanagesan S. Jesurani R. Velmurugan T. Kalaivani 《Journal of Materials Science: Materials in Electronics》2012,23(4):952-955
M-type Hexaferrites B0.5Sr0.5Fe12−2x
Ni
x
Zr
x
O19 were synthesized and investigated. The XRD patterns show single phase of the magnetoplumbite barium strontium ferrite and
no other phases were present. The samples exhibit well defined crystallization; all of them are hexagonal platelet grains.
As the substitution level increased from x = 0.2 to 0.8 mol%, the grains are agglomerated and the average diameter increased. This suggests that Ni–Zr substitution
increases the grain size, as observed in the FE-SEM micrographs. The results of magnetic measurement revealed that Ms of barium strontium hexaferrite increased when the value of x increased from 0 to 0.4 mol% and then decreased with the increasing Ni–Zr content. The Hc decreases remarkably with increasing Ni and Zr ions content. Hard magnetic material is converted into soft magnetic material
when the substitution level is increased from 0.2 to 0.8 mol%. In particular, Ba0.5Sr0.5Fe12−2x
Ni
x
Zr
x
O19 with x = 0.2, 0.4, 0.6, 0.8 mol% has suitable magnetic characteristics with particle size small enough for high-density magnetic
recording applications. 相似文献
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M. Sivakumar S. Kanagesan V. Umapathy R. Suresh Babu S. Nithiyanantham 《Journal of Superconductivity and Novel Magnetism》2013,26(3):725-731
CoFe2O4 particles were synthesized using metallic nitrates and polyvinylpyrolidone (PVP) using sol–gel method followed by calcination for 2 h at 960 °C. PVP performed as a surfactant and the effect of various concentrations of PVP on the resultant CoFe2O4 powder was studied. The resultant samples were characterized by XRD, TG/DSC, HR-SEM and VSM. X-ray diffraction results indicated the crystalline phase of CoFe2O4 particles and impurity phase of hematite was observed for higher PVP concentrations. SEM images demonstrated the influence of PVP concentration on the size of the particles. By VSM measurements, the variations in magnetic properties with respect to PVP concentration are studied. All the magnetic characteristics H c , M s and M r increased for 6 wt% and 15 wt% of PVP concentration. The CoFe2O4 particles synthesized with the optimum concentration of PVP may be very attractive for potential applications because of their outstanding magnetic properties (M s =81.1 Am2/kg, H c =831 Gauss). 相似文献
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Samikannu Rakesh Venu Thulasiraman Muthusamy Sarojadevi 《Polymer Engineering and Science》2015,55(1):47-53
A series of azo functionalized diols were synthesized through diazotization which involves the reaction of amine with phenol and 2,6‐dimethyl phenol. Four different amines have been used to prepare five bisphenols. These bisphenols were converted to their corresponding cyanate esters by treatment with cyanogen bromide (BrCN) in the presence of triethylamine (Et3N). The chemical structures of the prepared compounds were characterized with Fourier Transform Infrared, 1H‐NMR, 13C‐NMR spectroscopy, and elemental analysis. Dynamic curing behavior was investigated using differential scanning calorimetry. The maximum curing temperature of these cyanate esters are in the range of (186–208°C). Tg values of the polycyanurate networks are in the range of 245–276°C. The thermal properties of cured cyanate ester were studied at a heating rate of 10°C min?1 in N2 atmosphere. The polymers showed excellent thermal stability (T10 was found to be in the range 405–438°C) and the percentage of char yield at 800°C were found to be 30–49. The flame retardancy of the cyanate ester resins have been studied using limited oxygen index value which is in the range of 29.5–37.1 at 800°C. POLYM. ENG. SCI., 55:47–53, 2015. © 2014 Society of Plastics Engineers 相似文献
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S. Kanagesan S. Jesurani R. Velmurugan S. Prabu T. Kalaivani 《Journal of Materials Science: Materials in Electronics》2012,23(8):1511-1514
Magnetic materials are important electronic materials that have a wide range of industrial and commercial applications. Barium strontium hexaferrite (Ba0.5Sr0.5Fe12O19-BSF) were prepared by a sol–gel method using d-Fructose as fuel and the heat treatment was carried out in a microwave furnace. The effects of the sintering temperature on the morphology, crystalline structure and magnetic properties are studied. Sintering temperature affected the grains in compact samples. The sintered product possessed dense microstructure with clear micro grains and is in consistence with the XRD analysis based on the peak intensity of the (107) plane. Magnetic measurement shows that the barium strontium hexaferrite sample sintered at 1,150?°C has the coercive field of 1,998 Gauss, remnant magnetization of 38.87?emu/g and the saturation magnetization of 53.44?emu/g. 相似文献