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TN Ruckmongathan 《Pramana》1999,53(1):199-212
Liquid crystal displays had a humble beginning with wrist watches in the seventies. Continued research and development in
this multi-disciplinary field have resulted in displays with increased size and complexity. After three decades of growth
in performance, LCDs now offer a formidable challenge to the cathode ray tubes (CRT).
A major contribution to the growth of LCD technology has come from the developments in addressing techniques used for driving
matrix LCDs. There are several approaches like passive matrix addressing, active matrix addressing and plasma addressing to
drive a matrix display.
Passive matrix LCD has a simple construction and uses the intrinsic non-linear characteristic of the LCD for driving. Departure
from conventional line by line addressing of a passive matrix has resulted in improved performance of the display. Orthogonal
functions have played a crucial role in the development of passive matrix addressing. Simple orthogonal functions that are
useful for driving a matrix LCD are introduced. The basics of driving several rows simultaneously (multi-line addressing)
are discussed by drawing analogies from multiplexing in communication. The impact of multi-line addressing techniques on the
performance of the passive matrix LCDs in comparison with the conventional technique will be discussed. 相似文献
2.
MAO Feng SHI YiPeng XUAN LiJun SU WeiDong & WU JieZhi State Key Laboratory for Turbulence Complex Systems College of Engineering Peking University Beijing China University of Tennessee Space Institute Tullahoma TN USA 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
As a continuation of a recent linear analysis by Mao et al.(Acta Mech Sin,2010,26:355),in this paper we propose a general theoretical formulation for the compressing process in complex Newtonian fluid flows,which covers gas dynamics,aeroacoustics,nonlinear thermoviscous acoustics,viscous shock layer,etc.,as its special branches.The principle on which our formulation is based is the maximally natural and dynamic Helmholtz decomposition of the Navier-Stokes equation,along with the kinematic Helmholtz decompos... 相似文献
3.
J. W. Mcfarland J. J. Beaulieu L. N. Arrey L. M. Frey 《Journal of heterocyclic chemistry》1988,25(5):1431-1434
4-Toluenesulfonyl isocyanate cyclized with 1,2-epoxy-3-phenoxypropane and 2,3-epoxypropyl 4-methoxyphenyl ether, respectively, to give 3-(4-toluenesulfonyl)-5-phenoxymethylene-2-oxazolidone ( I ) and 3-(4-toluenesulfonyl)-5-(4-methoxyphenoxymethylene)-2-oxazolidone ( II ). Compounds I and II were hydrolyzed in 2 M sodium hydroxide solution to the corresponding uncyclized hydroxy amides, VII and VIII. Compound I was remarkably stable toward 6 M hydrochloric acid and amines. Styrene oxide, 1,2-epoxybutane, 3-chloro-1,2-epoxypropane, and 1-methoxy-2-methylpropylene oxide reacted with the isocyanate to afford 3-(4-toluene-sulfonyl)-4-phenyl-2-oxazolidone (III), 3-(4-toluenesulfonyl)-4-ethyl-2-oxazolidone ( IV ), 3-(4-toluenesulfonyl)-5-chloromethyl-2-oxazolidone ( V ), and 3-(4-toluenesulfonyl)-4,4-dimethyl-5-methoxy-2-oxazolidone ( VI ), respectively. The yield of VI was constant over a temperature range of 25–90°. 相似文献
4.
Arnold A Arrey TN Karas M Persike M 《Rapid communications in mass spectrometry : RCM》2011,25(19):2844-2850
A simple, sensitive and fast method for the determination of melamine and its derivatives in milk powder using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was developed. Neither time-consuming sample preparation, nor special target plates, or other extra equipment are necessary. The common matrix sinapinic acid (SA) was used with a dried-droplet preparation. Detection limits (signal-to-noise (S/N) ratio = 3) for standard solutions of melamine, ammeline and cyanuric acid were 10, 25 and 10 μg/L, respectively. The limit of quantification (LOQ) for melamine was 25 μg/L and excellent linearity (R(2): 0.9990) was maintained over the range of 10-2000 μg/L. Ammeline and cyanuric acid were analyzed with an LOQ of 50 μg/L and also excellent linearity (R(2): 0.9997 and R(2): 0.9998). Good accuracy and precision were obtained for all concentrations within the range of the standard curve. The developed method was successfully used for the determination of melamine, ammeline and cyanuric acid in milk powder samples with a simple sample preparation. The LOQ of melamine was 0.5 μg/g. Ammeline and cyanuric acid were detectable at 0.5 and 5 μg/g. This method showed excellent accuracy, precision and linearity and significantly reduces the needed analysis time, as only approximately 10 s/sample measuring time is required. To the authors' knowledge, this is the first published method to quantify melamine and derivatives by MALDI-TOF-MS. 相似文献
5.
J. W. Mcfarland J. J. Beaulieu L. N. Arrey L. M. Frey 《Journal of heterocyclic chemistry》1988,25(5):1435-1436
4-Toluenesulfonyl isothiocyanate reacted with 1,2-epoxy-3-phenoxypropane and 2,3-epoxypropyl 4-methoxyphenyl ether to give, respectively, 3-(4-toluenesulfonyl)-5-phenoxymethylene-2-oxazolidmethione ( I ) and 3-(4-toluenesulfonyl)-5-(4-methoxyphenoxymethylene)-2-oxazolidinethione ( II ) in high yields. The sulfonyl isothiocyanate reacted further with styrene oxide to give a mixture of oxazolidinethiones from which a solid III was isolated. The structure of III is either the 4- or 5-phenyl derivative of 3-(4-toluenesulfonyl)-2-oxazolidinethione. Reactions of the isothiocyanate with 3-chloro-1,2-epoxypropane and 1,2-epoxybutane afforded, respectively, 3-(4-toluenesulfonyl)-5-chloromethyl-2-oxazolidinethione ( IV ) and 3-(4-toluenesulfonyl)-4-ethyl-2-oxazolidinethione ( V ). Evidence for structures was by pmr, ir, and elemental analyses. 相似文献
6.
Lemeer S Kunold E Klaeger S Raabe M Towers MW Claudes E Arrey TN Strupat K Urlaub H Kuster B 《Analytical and bioanalytical chemistry》2012,402(1):249-260
Owing to its broad biological significance, the large-scale analysis of protein phosphorylation is more and more getting into
the focus of proteomic research. Thousands of phosphopeptides can nowadays be identified using state-of-the-art tandem mass
spectrometers in conjunction with sequence database searching, but localizing the phosphate group to a particular amino acid
in the peptide sequence is often still difficult. Using 180 individually synthesized phosphopeptides with precisely known
phosphorylation sites (p-sites), we have assessed the merits of the Mascot Delta Score (MD score) for the assignment of phosphorylation
sites from tandem mass spectra (MS/MS) generated on four different matrix-assisted laser desorption ionization (MALDI) mass
spectrometers including tandem time-of-flight (TOF/TOF), quadrupole time-of-flight, and ion trap mass analyzers. The results
show that phosphorylation site identification is generally possible with false localization rates of about 10%. However, a
comparison to previous work also revealed that phosphorylation site determination by MALDI MS/MS is less accurate than by
ESI-MS/MS particularly if several and/or adjacent possible phosphorylation acceptor sites exist in a peptide sequence. We
are making the tandem MS spectra and phosphopeptide collection available to the community so that scientists may adapt the
MD scores reported here to their analytical environment and so that informatics developers may integrate the MD score into
proteomic data analysis pipelines. 相似文献
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