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101.
The optical properties of vapour chopped and nonchopped bismuth oxide thin films of two thicknesses 1500 Å and 2000 Å have been studied. The films were prepared by thermal oxidation in air; of vacuum evaporated vapour chopped and nonchopped bismuth thin films. As revealed by XRD studies, multiphase and polycrystalline bismuth oxide thin films were obtained. The refractive index was found to increase with the thickness and exposure to air for 40 days. The vapour chopped films showed higher refractive index, band gap and lower grain size than those of nonchopped films. The films showed high transmittance in the visible spectrum. The ageing effect on the vapour chopped films was found low. 相似文献
102.
In this paper, we establish the influence of pump power on the tuning characteristics of a filterless erbium-doped fiber laser,
operating in the L band. Tunable action is achieved with the control of intra cavity loss. The explicit dependence of tunability
on the average inversion levels is brought out. The shift in the lower limit of tuning range and the non-linear dependence
of lasing wavelength on the intra cavity loss are analytically deduced using the gain spectra and experimentally interpreted
using amplified spontaneous emission spectra. Continuous tunability is achieved with the careful control of pump power.
PACS 42.55.Wb; 42.60.Da; 42.55.-f 相似文献
103.
104.
S. Vijaya Lakshmi 《Applied Scientific Research》1967,17(4-5):355-358
Summary The problem of two dimensional and three dimensional (asymmetric) jet flows through an orifice in planex=0, when the boundary conditions on the same plane are prescribed, has been studied. 相似文献
105.
D. Vijaya Bharathi Kishore Kumar Hotha Pandu Ranga Reddy Kolagatla V. Venkateswarlu 《Biomedical chromatography : BMC》2013,27(5):589-598
Low dose to very high dose aspirin is used to prevent heart attack. We have developed and validated a sensitive and robust method that could detect low levels of aspirin and salicylic acid in plasma and also a novel sample collection procedure to carry out sample preparation at room temperature. The total run time was 3.00 min; the developed method was validated in human plasma with a lower limit of quantitation of 0.99 ng/mL for aspirin and 2.01 ng/mL for salicylic acid. A linear response function was established for the range of concentrations 0.99–756.20 ng/mL (r > 0.998) for aspirin and 2.01–2486.86 ng/mL for salicylic acid. The intra‐ and inter‐day precision values for aspirin and salicylic acid met the acceptance as per FDA guidelines. The developed assay method was applied to an oral pharmacokinetic study in humans. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
106.
107.
Layered double hydroxide (LDH)–supported nano noble metal heterogeneous catalysts are synthesized by ion exchange of K2PtCl6, Na2PdCl4 and impregnation of RhCl3 .3H2O followed by reduction with H2. The LDH–Rh, Pt, and Pd catalysts are tested in the enantioselective hydrogenation of ethyl pyruvate to ethyl lactate with very good yields and enantiomeric excess's (e.e.'s) of up to 72% were obtained with Pt. The catalyst was recovered and reused for several cycles with consistent activity. 相似文献
108.
Hong‐Jyune Lin Avijit Kumar Adak L. Vijaya Raghava Reddy Prof. Shih‐Hsiung Wu Prof. Chun‐Cheng Lin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(24):7989-7998
A method for the stereocontrolled synthesis of a bacterial phosphoglycolipid (PGL 1 ) isolated from thermophilic bacteria is described. The key features of the synthesis include a highly α‐selective glycosylation reaction between a trichloroacetimidate donor and a D ‐lyxose‐derived primary alcohol acceptor and the late‐stage incorporation of the phospholipid. 相似文献
109.
B. T. Ramanjaneyulu Virsinha Reddy Panjab Arde Sriram Mahesh Dr. R. Vijaya Anand 《化学:亚洲杂志》2013,8(7):1489-1496
A combination of the oxidative N‐heterocyclic carbene catalysis and click chemistry has been explored for the direct, one‐pot synthesis of 1,2,3‐triazole derivatives from aromatic aldehydes. This procedure was found to be very efficient and a variety of 1,2,3‐triazole derivatives could be accessed through their corresponding propargyl esters in moderate‐to‐good yields under mild conditions. 相似文献
110.
Sandip V. KamatJ.B. Yadav Vijaya PuriR.K. Puri O.S. Joo 《Applied Surface Science》2011,258(1):482-488
Poly (3-methyl thiophene) thin films were prepared by chemical bath deposition technique on glass substrate; the prepared thin films were characterized for structural, morphological and optical properties. The variation in the oxidant concentration has an influence on the properties of the P3MeT thin films. The increase in the oxidant concentration leads to increase in the thickness of the film. The binding energy increases due to increase in oxidation concentration. The P3MeT thin films show smooth surface morphology with increase in oxidant concentration whereas the contact angle of the thin film decreases with increase in oxidant concentration. The optical absorbance of these thin films was found to increase with decrease in the optical band gap due to increase in oxidant concentration. 相似文献