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71.
G.N.D.S. Sudhakar 《Journal of sound and vibration》2011,330(10):2299-2313
Model based methods for fault identification in rotating systems are gaining importance for the last three decades due to their ability to identify both location and severity of the fault. Model based methods are of different types. Among them, equivalent loads minimization method is one method. In this method, fault is identified in a rotor bearing system by minimizing difference between equivalent loads estimated in the system due to the fault and theoretical fault model loads. This method has a limitation that the error in identified fault parameters increases with decrease in number of measured vibrations. Thus a comprehensive methodology for fault identification with minimum error even in case of fewer measured vibrations is attempted in the present work. Two different approaches: equivalent loads minimization and vibration minimization method are applied for the identification of unbalance fault in a rotor system. Unbalance fault is identified using proposed methods by measuring transverse vibrations at only one location. 相似文献
72.
Shrinivas S. Kottawar Shaphi A. Siddiqui Shrikant S. Pendalwar Wamanrao N. Jadhav Sudhakar R. Bhusare 《Research on Chemical Intermediates》2014,40(8):2929-2934
The molecular iodine-catalyzed direct coupling of indoles with 1,3-dicarbonyl compounds is described. This new method for C–C bond formation allows high functional group tolerance, regioselectivity, and scope under mild conditions. 相似文献
73.
Rajenahally V. Jagadeesh Y. Sree Sandhya P. Karthikeyan S. Sudhakar Reddy P. Pradeep Kumar Reddy M. Viniod Kumar 《合成通讯》2013,43(16):2343-2349
α-Chloroalkyl aryl ethers has been obtained in good yields from phenols and aryl α-chloroalkyl sulfides. 相似文献
74.
The modification of coatings resins by graft polymerization of vinylidene chloride should produce a coatings binder with improved barrier properties. For superior color stability, vinylidene chloride must be copolymer-ized with other monomers such as alkyl acrylates and methacrylates. Ceric ion initiation was used to graft vinylidene chloride free-radically onto a model alcohol-containing polymer, polyvinyl alcohol. The effects of various reaction parameters on vinylidene chloride grafting were studied. Graft copolymers were characterized using selective solvent extraction, FTIR, SEM, XES, DSC, and x-ray diffraction. 相似文献
75.
Amna Ali Atri Deshamukhya Sudhakar Panda M. Sami 《The European Physical Journal C - Particles and Fields》2011,71(6):1672
We revisit our earlier investigations of the brane–antibrane inflation in a warped deformed conifold background, reported
in Phys. Lett. B 674, 131 (2009), where now we include the contributions to the inflation potential arising from imaginary anti-self-dual (IASD) fluxes including
the term with irrational scaling dimension discovered recently in and . We observe that these corrections to the effective potential help in relaxing the severe fine tunings associated with the
earlier analysis. Required number of e-folds, observational constraint on COBE normalization and low value of the tensor to
scalar ratio are achieved which is consistent with WMAP seven years data. 相似文献
76.
Self assembled micro masking effect in the fabrication of SiC nanopillars by ICP-RIE dry etching 总被引:1,自引:0,他引:1
A. KathalingamMi-Ra Kim Yeon-Sik ChaeS. Sudhakar T. MahalingamJin-Koo Rhee 《Applied Surface Science》2011,257(9):3850-3855
This report presents the results of the novel fabrication of 4H-SiC pillars with nanopores using ICP-RIE dry etching. Cl2/Ar gas plasma with various mass flow rates was used in this etching process to produce SiC nanopillars without using patterned etch mask. Cylindrical pillars of 300 nm diameter and 500 nm height with smooth side walls were etched on SiC wafer. The etching condition for the optimized fabrication of SiC nanopillars is presented in this report. Each nanopillar has been produced with a nanosize pore at the center along its length and up to the middle of the cylindrical nanopillar; it is a unique feature has not ever been reported in case of SiC. Inclusion of oxygen was found influence the formation of nanopillars by the effect of SiO2 micro masking. The formation of self assembled SiO2 layer and its micro masking effect in the fabrication of this unique nanostructure has been investigated using TEM, STEM and EDAX measurements. 相似文献
77.
V. Siddaiah G. Mahaboob Basha D. Sudhakar R. Srinuvasarao Y. Santosh Kumar 《合成通讯》2013,43(16):2191-2197
A simple and alternative method has been developed for the synthesis of 4-benzylidene-2-phenyl-5(4H)-oxazolones via reactions of hippuric acid with various aldehydes in the presence of 2-chloro-4,6-dimethoxy-1,3,5-triazine/N-methylmorpholine at 75 °C. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
78.
Sudhakar Maddala Anirban Panua Dr. Parthasarathy Venkatakrishnan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(64):16013-16020
While intramolecular Scholl oxidative coupling between two arenes is common, successful C−C heterocoupling between thiophene and arene is scarce. The latter is due to the notorious reactivity of thiophene towards polymerization under oxidative conditions. This report systematically demonstrates how topological variation of electronics and reactivity in thiophene substrates can lead to efficient oxidative heterocoupling. Bis(biaryl)thiophenes having reactive α- and β-positions open are the choice of substrates. The cyclizing arene partners are so electronically tuned for thiophene's reactivity (at α- and β-) as to establish C−C bond oxidatively generating symmetrical as well as unsymmetrical diphenanthrothiophenes which are basic thiananographenes. Depending on the cyclizing-couple's electronics, either arene- or thiophene-centered oxidation initiates C−C heterocoupling. The potential utility of these simple thiananographenes is further unfurled by converting them to functional N−/C-graphene segments that are aza-corannulene precursor and tetrabenzospirobifluorene. Their bright emission and extended electrochemical stability are remarkable that may be potentially important and applicable. 相似文献
79.
Madasu Madhu Sai Reddy Doda Prem Kumar Begari Krishna Rao Dasari Gangadhar Thalari Sudhakar Kadari Jhillu Singh Yadav 《Journal of heterocyclic chemistry》2021,58(4):942-946
Enantioselective and a highly concise total synthesis of Ambrisentan are described. The chiral auxiliary controlled enantioselective epoxidation (Azerad protocol), photochemical regioselective epoxide opening, and base mediated ester hydrolysis reactions are the key reactions. 相似文献
80.
Bhimrao D. Sarwade Sudhakar S. Mahajan 《Journal of polymer science. Part A, Polymer chemistry》1991,29(6):825-829
Polyamides were synthesized from diacids containing a s-triazine ring and two aromatic diamines, namely 4,4′-diaminodiphenyl ether (ODA) and 4,4′-diaminodiphenylmethane (MDA), by direct polycondensation using the phosphorylation reaction. Polymers thus obtained were characterized by viscosity measurement, IR spectroscopy, thermogravimetry, X-ray diffraction, and solubility tests. These polyamides had inherent viscosities in the range of 0.51–0.77 dL/g, and were amorphous in nature. All the polymers were readily soluble in various organic solvents and did not lose weight below 270°C in air. 相似文献