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1.
An efficient synthesis of isothiazolidines in good yields is described. 相似文献
2.
Let [a, b] be any interval and let p0, p1, pk be any three polynomials of degrees 0, 1, k, respectively, where k 2. A set of necessary and sufficient conditions for the existence of an f in C[a, b] such that pi is the best approximation to f from the space of all polynomials of degree less than or equal to i, for all i = 0, 1, k, is given. 相似文献
3.
4.
Satchidanand S. Biswas Achamkulangara Sethumadhavan Pappu S. Murty 《Mikrochimica acta》1991,103(1-2):71-77
Inductively coupled plasma atomic emission spectrometry (ICP-AES) was employed to determine Y, Sm, Eu, Gd, Dy, Ho and Er in high purity terbium oxide. Terbium oxide was dissolved in 0.5 mol/l HNO3 and nebulized into the plasma generated by a 56 MHz RF generator at 1.5 kW output power. Using a Jobin-Yvon 1-m Czenry-Turner high resolution, high dispersion scanning monochromator, lines mutually interference-free as well as free of interference from the matrix Tb were chosen for the seven analytes. A set of standards containing the analytes in the concentration range 0.01–1.0 gmg/ml with 1 mg/ml Tb was used for calibration. It was necessary to apply background correction to the gross analyte line intensities in order to obtain linear calibration plots for the analytes. 相似文献
5.
J. Ravichandran C. M. Lakshmanan B. Sivasankar 《Reaction Kinetics and Catalysis Letters》1996,59(2):301-308
Treatment of montmorillonite and vermiculite with hydrochloric acid results in an overall increase in acidity and acidic sites. IR and DSC studies of base adsorbed catalysts have revealed the heterogeneity of surface acidity on the activated catalysts. Clay catalysts have been found to dehydrate 1-butanol to 1-butene, which directly isomerizes tocis- andtrans-2-butenes, confirming the presence of Lewis and Brönsted acid sites. Cumene cracking studies using the clay catalyst also confirm the presence of Brönsted acid sites. The temperature and concentration of acid have been found to have a significant influence on the catalytic activity. 相似文献
6.
D. Ravichandran K. Yamakawa A.S. Bhalla R. Roy 《Journal of Sol-Gel Science and Technology》1997,9(1):95-101
Phase pure powder and thin films of the novel ferroelectric materials SrBi2Ta2O9 (SBT) have been prepared using the organic precursors. The xero-gel formed was dried and characterized using TGA and DTA
to determine the organic burn out and crystallization temperature of SBT. Powder X-ray diffraction was used systematically
to check the crystallinity of SBT. Phase pure SBT powder was formed as low as 650°C and thin films at 600°C in comparison
to other earlier reported work. SEM micrographs show a grain size of ≈0.1 μm and show crack free films with a film thickness
of 2 μm. 相似文献
7.
The effect of repeated loading from mechanically simulated hull slamming on foam core sandwich composites was investigated
utilizing a novel technique that simultaneously measured temperature and displacement while cyclic loading occurred. Thermoelastic
Stress Analysis (TSA) and Digital Image Correlation (DIC) techniques were combined using a single infrared camera for characterization
of the foam core. Improved stress fields with TSA results were found through deformation compensation. Initial work approximating
hull slamming conditions mechanically utilizing a custom device were performed. Mechanically loading offers several benefits
over water impact investigations, including easy access to the sample during the slamming event, an unobstructed optical path,
and accelerated testing. Evolving stress fields under long-duration, repeated simulated hull slamming loading were observed
around a growing delamination crack between the foam core and skin. 相似文献
8.
9.
Shirazi Muhammad Faizan Wijesinghe Ruchire Eranga Ravichandran Naresh Kumar Kim Pilun Jeon Mansik Kim Jeehyun 《Optical Review》2017,24(2):219-225
Optical Review - A dual-path handheld system is proposed for cornea and retina imaging using spectral domain optical coherence tomography. The handheld sample arm is designed to acquire two images... 相似文献
10.
Giridharan Loganathan Suresh Krishnaraj Jayaprakash Muthumanickam Ravichandran K 《Journal of Chemometrics》2015,29(1):59-68
In order to bring out the nature of the factors influencing lake water composition, multivariate statistical analysis and trend analysis were performed based on the hydrochemical data of the study area, namely, South Chennai. Change in land use pattern and settlements along the banks of the lakes alters the quality and quantity of the surface water. In the present study, the R‐mode factor analysis and cluster analysis were applied to the geochemical parameters of the water to identify the factors affecting the chemical composition of the lake water. Dendograms of both the seasons give three major clusters, reflecting the groups of unpolluted to moderately polluted, polluted, and heavily polluted stations. The movement of stations from one cluster to another clearly brings out the seasonal variation in the chemical composition of the lake water. The complex hydrochemical data of the surface water were interpreted by condensing them into three major factors. Factor score analysis was used successfully to delineate the stations under study and the role of the contributing factors, and the nature of factors responsible for the variation in chemical composition of the water has been clearly brought out. Results of trend analysis using ArcGIS clearly indicate that the trend in water quality is deteriorating at a faster rate in the eastern part of the study area. It is understood that although natural shifts probably can account for some of the variation, it is most likely that human activities play a major role in affecting the water quality on a regional scale. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献