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91.
N. Sankara Subramanian B. Santhi V. Veeraganesh C. Vinoth G. Murugan G. Karthik Subbaraj 《Ionics》2004,10(1-2):56-62
Present work deals with the preparation of TiO2 thin films of different thicknesses by PVD technique using an electron beam and to characterize the films for oxygen gas
detection. The films were characterized using optical transmission measurements, XRD and atomic force microscopy. From the
spectral data, the extinction, absorption coefficient and refractive index of the films are evaluated and reported. The optical
band gap energy varies between 3 and 3.68 eV. The XRD pattern confirms the formation of polycrystalline anatase structure
of Titanium with preferred orientation of (110) plane. The AFM images indicate the presence of coarse and fine grains with
uniform as well as smooth surfaces over the entire range of the analyzed surface. Response characteristics of TiO2 thin films for oxygen gas detection are studied, which indicate a low response time of 120 seconds and high sensitivity of
16 at the operating temperature 450 °C.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
92.
Philip N Klein Sairam Subramanian 《Journal of Algorithms in Cognition, Informatics and Logic》1997,25(2):205-220
We give a randomized parallel algorithm for computing single-source shortest paths in weighted digraphs. We show that the exact shortest-path problem can be efficiently reduced to solving a series of approximate shortest-path subproblems. Our algorithm for the approximate shortest-path problem is based on the technique used by Ullman and Yannakakis in a parallel algorithm for breadth-first search. 相似文献
93.
M. Murugesan P. Selvam M. Sharon L. C. Gupta R. Pinto C. S. Gopinath S. Subramanian 《Applied Physics A: Materials Science & Processing》1997,64(2):177-179
Single phase Ba-free Sr-based YSr2Cu
3-x
M
x
O7+δ (M=Mo, W and Re) compounds have been stabilized by chemical doping. Superconductivity is observed for these phases in the
range 30–45 K. X-ray diffraction studies suggest a relatively small orthorhombicity compared to Ba-analogue. X-ray photoelectron
spectroscopic investigations reveal that the stabilizing cations are in the hexavalent state. The observation of the higher
oxidation state of M-ions accounts for the excess oxygen content in these phases which is in accordence with the diffraction
results.
Received: 10 June 1996 / Accepted: 20 September 1996 相似文献
94.
95.
96.
97.
Archana Sivasubramaniyan Ranganathan Raja Dinesh Murugan Arul Ponnusamy Ponnuswamy Alagusundaram Kalaiselvi Patchaiah Chellammal Subbiah Subramanian Gopalan 《Research on Chemical Intermediates》2017,43(4):2471-2490
Research on Chemical Intermediates - A library of pyrazolinyltriazole hybrids (3a–l, 4a–l) was synthesized via azide–alkyne dipolar (Huisgen) cycloaddition of azidoacetyl... 相似文献
98.
99.
J. Premakumari G. Allan Gnana Roy A. Antony Muthu Prabhu G. Venkatesh V. K. Subramanian N. Rajendiran 《Journal of solution chemistry》2011,40(2):327-347
The spectral characteristics of 2,4-dihydroxyazobenzene (DHAB, sudan orange G) and 4-hydroxyazobenzene (HAB) have been studied
in various solvents, different hydrogen ion and β-cyclodextrin (β-CD) concentrations, and are compared with azobenzene (AB). The inclusion complexes of the above molecules with β-CD were analyzed by UV-vis spectrometry, flourometry, FT-IR, 1H NMR, SEM and DFT methods. The solvent study shows that only the azo form is present in DHAB and HAB molecules. The unusually
large red shift observed in acidic solutions indicates both molecules exhibit azo-hydrazo tautomerization. In the β-CD solutions, the increase in fluorescence intensity and large bathochromic shift in the S1 state indicates that DHAB and HAB form 2:2 inclusion complexes, whereas AB forms a 1:1 inclusion complex. 相似文献
100.
Subramanian NH Manigandan P Wille A Radhakrishnan G 《Journal of chromatographic science》2011,49(8):603-609
This work describes a new method for the determination of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in water matrices by suppressed conductivity detection. Separation was achieved by isocratic elution on a reversed-phase column thermostated at 45°C using an aqueous mobile phase containing boric acid and acetonitrile. The PFOA and PFOS content in the water matrix were quantified by a pre-concentration technique. For the concentration range of 1 to 15 ng/mL and 2 to 30 ng/mL, the linear calibration curve for PFOA and PFOS yielded coefficients of determination (R(2)) of 0.9995 and 0.9985, respectively. The relative standard deviations were smaller than 1.5% for PFOA and PFOS. The retention-time precision of four consecutive 12 h injections was smaller than 0.641% and 0.818%, respectively. The presence of common divalent cations, such as calcium, magnesium, and iron in water matrices impairs PFOS recovery. This drawback was overcome by applying inline matrix elimination method. The optimized method was successfully applied for drinking water, ground water, and seawater samples. 相似文献