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71.
S.K. Rout T. Badapanda E. Sinha S. Panigrahi P.K. Barhai T.P. Sinha 《Applied Physics A: Materials Science & Processing》2008,91(1):101-106
BaTi0.6Zr0.4O3 (BTZ) ceramic was synthesized by a soft chemical route. X-ray diffraction at room temperature shows that the sample has cubic
perovskite structure with space group Pm-3m. Temperature dependent dielectric study of the sample has been investigated in
the frequency range from 50 Hz to 1 MHz. The density of the sample was determined using Archimedes’ principle and found to
be ∼ 97% of the X-ray density. The average grain size in the pallet was found to be ∼ 1 μm. The dielectric constant peaks
at temperature Tm which is dependent on the frequency. The dielectric relaxation rate follows the Vogel–Fulcher relation with activation energy = 0.0185 eV,
and freezing temperature = 186 K. All these measurements confirm that BTZ is a relaxor ferroelectric.
PACS 77.22.Jp; 77.84.-s; 77.80.Bh; 77.22.Gm 相似文献
72.
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A facile methodology has been described which has successfully simplified the generation of sulfonamides, thiosulfonates and symmetric disulfanes. This “trio” of reactions occur in an open air metal free atmosphere and has also been scaled up to grams making it suitable for commercialization. The reactions also have been successfully carried out with asymmetric variants, thus contributing to the chiral pool. The user friendly “trio” enables easy generation of these versatile sulfur analogues and the reaction condition employed depict an economic outline. 相似文献
74.
L.N. Patnaik R.K. Satapathy S.N. Patnaik B.K. Misra M.K. Rout 《European Polymer Journal》1980,16(2):117-120
The present communication discusses the kinetics of the retarding effect of phenol on the polymerization of acrylonitrile initiated by azobisisobutyronitrile (AIBN). The results are treated on the basis of the scheme proposed by Tüdös et al. 相似文献
75.
Substituent effects in the reactivities of phenols towards polyacrylonitrile radicals have been studied in terms of Swain and Luptons' field (Fk) and resonance (Rk) components of the substituent parameters and the unique positional weighting factors (fj and rj) proposed by Williams and Norrington, with the aid of the following equation: Pi′s are the rate parameters, Pi0 being that for a standard reference compound. Two types of rate parameters have been employed—one, suggested by Simonyi, Tüdös and Pospisil (β) and another, suggested by us, (K), which is obtained from a plot of [Monomer]/(rate of polymerisation) vs [Phenol]. The correlations have been found to be quite satisfactory with both β and K. An attempt has been made to ascertain the nature of the transition state from the reaction parameters αi and βi; a dipolar transition state is suggested. The anomalous kinetic behaviour of hydroxy phenols has been discussed. 相似文献
76.
One‐Step Electrodeposition of NiCo2S4 Nanosheets on Patterned Platinum Electrodes for Non‐Enzymatic Glucose Sensing
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Dr. Padmanathan Karthick Kannan Dr. Chunxiao Hu Prof. Dr. Hywel Morgan Dr. Chandra Sekhar Rout 《化学:亚洲杂志》2016,11(12):1837-1841
The preparation of NiCo2S4 (NCS) nanosheets on photolithographically patterned platinum electrodes by electrodeposition was explored. The as‐prepared nanosheets were systematically characterized by field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy techniques. The NCS‐modified Pt electrode was used as a non‐enzymatic glucose sensor. The sensor response exhibited two linear regions in glucose concentration, with a limit of detection of 1.2 μm . The sensors showed that the as‐prepared NCS nanosheets have excellent electrocatalytic activity towards glucose with long stability, good reproducibility, and excellent anti‐interference properties, and thus, this material holds promise for the development of a practical glucose sensor. 相似文献
77.
A sensitive, simple, rapid, and efficient high-performance thin-layer chromatographic (HPTLC) method has been developed and validated for the analysis of berberine in marketed Ayurvedic formulations containing Berberis aristata DC for regulatory purposes. Chromatography of methanolic extracts of these formulations was performed on silica gel 60 F254 aluminum-backed TLC plates of 0.2 mm layer thickness. The plate was developed up to 66 mm with the ternary-mobile phase butanol-acetic acid-water (8 + 1 + 1, v/v/v) at 33 +/- 5 degrees C with 5 min of tank saturation. The marker, berberine, was quantified at its maximum absorbance of 350 nm. The limit of detection and limit of quantitation values were found to be 5 and 10 ng/spot. The linear regression analysis data for the calibration plot showed a good linear relationship with correlation coefficient = 0.9994 in the concentration range of 10 to 50 ng/spot for berberine with respect to peak area. The instrumental precision was found to be 0.49% coefficient of variation (CV), and repeatability of the method was 0.73% CV. Recovery values from 98.27 to 99.11% indicate excellent accuracy of the method. The developed HPTLC method is very accurate, precise, and cost-effective, and it has been successfully applied to the assay of marketed formulations containing B. aristata for determination of berberine. 相似文献
78.
Marek Pietraszkiewicz Jerzy Karpiuk RafaŁ Gasiorowski Ashok Kumar Rout 《Journal of inclusion phenomena and macrocyclic chemistry》1997,28(4):325-334
Three novel ligands incorporating two, or three 3,3-biisoquinoline-2,2-dioxide units have been synthesized using modified standard methods of cyclization. These ligands formed photoactive mononuclear complexes with a Eu(III) cation. The ligand with two photoactive units displayed a better quantum yield for the Eu(III) emission (0.064) upon UV excitation than the other two complexes incorporating three units, whose luminescence quantum yields have been estimated to be below 0.01. The luminescence of the Eu(III) complex with two sensitizing units was not stable in aqueous solution, whereas with the two other complexes, their luminescence in solution remained for a couple of days. 相似文献
79.
Sahoo Sumanta Kumar Ratha Satyajit Rout Chandra Sekhar Mallik Archana 《Journal of Solid State Electrochemistry》2016,20(12):3415-3428
Journal of Solid State Electrochemistry - The study emphasizes on the scalable production and comparison of few layered graphene nanosheets (FLGNSs). The FLGNSs have been electrochemically... 相似文献
80.