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111.
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
112.
113.
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
114.
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
115.
116.
117.
P. Naveen B. Vijaya Pandiyan D. Anu F. Dallemer P. Kolandaivel R. Prabhakaran 《应用有机金属化学》2020,34(5):e5605
A new mixed nickel–sodium complex has been synthesized from Ni(ClO4)2 and tris(8-methyl 2-oxo-quinolidine amino ethylamine) with a 1:1 molar ratio in methanol and has been characterized by various analytical, spectroscopy and X-ray diffraction studies which confirmed an octahedral geometry around the nickel ion. Further, structural optimization of the complex was performed using DFT calculations. The ligand and complex were evaluated for their binding affinity with CT-DNA and an intercalative type of binding interaction was proposed from the absorption and fluorescence titration experiments. Albumin binding interaction of the ligand and complex was determined by absorption, fluorescence and synchronous spectral techniques at room temperature, suggesting the static quenching mechanism of BSA with the compounds. Antioxidant studies revealed the radical scavenging potential of Ni(II) complex. The anticancer activity of the ligand and complex was probed via in vitro cytotoxicity against human breast (MCF7) and lung (A549) cancer cell lines by MTT assay. Further, cytological changes observed in acridine orange/ethidium bromide and DAPI staining methods validated the cytotoxic potential of the complex. 相似文献
118.
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
119.
Surya Prakash Singh T. Vijaya Kumar M. Chandrasekharam L. Giribabu P. Yella Reddy 《合成通讯》2013,43(22):3982-3989
Highly efficient solvent-free aza-Michael additions of a variety of amines to α,β-unsaturated carbonyl compounds under microwave-irradiation conditions catalyzed by perchloric acid impregnated on silica gel (HClO4/SiO2) is reported. The reactions are completed within 2–7 min in a microwave oven to produce the corresponding adducts in excellent yields, and the catalyst can be recovered and reused. 相似文献
120.
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