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81.
H. Sommer A. Weiss H. Neumann R. D. Tomlinson 《Crystal Research and Technology》1990,25(10):1183-1187
Photoemission spectra of all CuInC2VI chalcopyrite compounds are measured at Hel line excitation and of CuInS2 also at excitation with ZrMζ radiation. It is found that the In5s – chalcogen p bonding states shift to lower binding energies with increasing anion mass. The energetic position of the S3s band of CuInS2 is also determined. The experimental results obtained are compared with previous measurements and with theoretical band structure calculations. 相似文献
82.
Electronic Structure of Manganese Complexes of the Redox‐Non‐innocent Tetrazene Ligand and Evidence for the Metal‐Azide/Imido Cycloaddition Intermediate
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Dr. Shivaiah Vaddypally Ian G. McKendry Warren Tomlinson Dr. Joseph P. Hooper Dr. Michael J. Zdilla 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10548-10557
The first synthetic manganese tetrazene complexes are described as a redox pair comprising anionic [Mn(N4Ad2)2]? ( 1 ) and neutral Mn(N4Ad2)2 ( 2 ) complexes (N4Ad2=[Ad‐N?N=N?N‐Ad]2?). Compound 1 is obtained in two forms as lithium salts, one as a cationic Li2Mn cluster, and one as a Mn–Li 1D ionic polymer. Compound 1 is electronically described as a MnIII center with two [N4Ad2]2? ligands. The one‐electron oxidized 2 is crystalized in two morphologies, one as pure 2 and one as an acetonitrile adduct. Despite similar composition, the behavior of 2 differs in the two morphologies. Compound 2 ‐ MeCN is relatively air and temperature stable. Crystalline 2 , on the other hand, exhibits a compositional, dynamic disorder wherein the tetrazene metallacycle ring‐opens into a metal imide/azide complex detectable by X‐ray crystallography and FTIR spectroscopy. Electronic structure of 2 was examined by EPR and XPS spectroscopies and DFT calculations, which indicate 2 is best described as a MnIII ion with an anion radical delocalized across the two ligands through spin‐polarization effects. 相似文献
83.
G.R. Tomlinson 《Journal of sound and vibration》1980,71(3):443-451
An analysis of the vector plot responses of lightly damped single degree-of-freedom systems with Coulomb damping has been made. The vector plots, as derived by using both an exact and an approximate method (the method of harmonic balance) are compared and it is shown that the distortion of the normally circular vector locus is due to the Coulomb damping. Although the vector plots of such systems are distorted it is also shown that the frequency gradient criterion is still applicable for location of a natural frequency even when the frictional force levels approach the excitation force levels. To permit estimation of the modal damping of these systems a criterion by means of which the limits of the useful frequency range can be specified is suggested. The criterion, which is based upon the quadrature input power necessary to excite the mode of vibration, is found to be equivalent to that obtained from the half power point theory when applied to linear systems. 相似文献
84.
M. J. Russell R. K. Moore M. J. Tomlinson 《The Journal of the Operational Research Society》1986,37(1):21-30
This article describes the methods which form the basis of contemporary automatic speech recognition systems. The two most prominent algorithms, dynamic time-warping and hidden Markov modelling, are described and compared. Particular attention is given to the role of dynamic programming in either approach. 相似文献
85.
86.
A three-dimensional photoelastic body can be represented by an optically equivalent model, which consists of a linear retarder,
δ, at a certain angle, θ, and a pure rotator, χ. These have been described as the characteristic retardation, δ, and the primary
and secondary characteristic directions, θ and θ+χ. Until now these characteristic parameters have only been determined using
manual, point-by-point collection methods which are involved and time consuming. Therefore an automated phase-stepping method
has been developed to enable the determination of the three characteristic parameters for three-dimensional or integrated
photoelasticity. Expressions have been derived to obtain δ, θ and θ+χ from six phase-stepped images. These images are collected
using a CCD camera and the full-field data is processed using a standard personal computer. This novel method allows accurate,
full-field maps of all three characteristic parameters to be obtained in a relatively short time, which makes full-field tomographic
reconstruction of photoelastic data a real possibility.
Both are SEM Members. 相似文献
87.
88.
89.
George Tomlinson W. Charles Schellenberg T. Viswanatha 《Applied biochemistry and biotechnology》1978,3(1):57-70
The binding of a series of related proteins, namely, α-chymotrypsin, chymotrypsinogen A, DIP-chymotrypsin, and TPCK-chymotrypsin,2 to affinity gels consisting of 4-phenylbutylamine or ε-aminocaproyl-d-tryptophanmethylester covalently attached to Sepharose 4B was investigated. Considerable heterogeneity in the binding was observed, both at the level of the affinity adsorbent and with respect to the proteins themselves. Both the aromatic moiety of the ligand and the positively charged isourea group introduced during the coupling of the ligand to the gel play a part in the stabilization of the binding of α-chymotrypsin. At least a part of the binding involves the substrate binding site of the enzyme. The existence of secondary binding sites on the proteins, capable of interaction with gel-bound ligand, is suggested by the observation that at fairly high levels of substitution of gel by ligand the zymogen and covalently modified enzyme species are also bound quite strongly. Since the level of gel substitution is difficult to control, the results emphasize the necessity of a thorough investigation of the binding properties of a given affinity medium prior to use in the separation of active chymotrypsin from inactive derivatives. 相似文献
90.
M. Dotrong R. Mehta G. A. Balchin R. C. Tomlinson M. Sinsky C. Y.-C. Lee R. C. Evers 《Journal of polymer science. Part A, Polymer chemistry》1993,31(3):723-729
Benzobisthiazole polymers containing mono-, bi-, and terthiophene moieties were synthesized through polycondensation in polyphosphoric acid of 2,5-diamino-1,4-benzenedithiol dihydrochloride with thiophene-2,5-dicarboxylic acid, 2,2′-bithiophene-5,5′-dicarboxylic acid, and 2,2′:5′,2″-terthlophene-5,5″-dicarboxylic acid, or their corresponding diacid chlorides, respectively. Intrinsic viscosities of up to 8.1 dL/g (methanesulfonic acid, 30°C) were recorded. Polymer structures were verified by elemental analysis and spectroscopic comparison of the polymers with appropriate model compounds. Onset of breakdown under thermogravimetric analysis in air occurred in the 460–590°C range with the benzobisthiazole polymers containing a monothiophene linkage being the most stable. Films suitable for third-order optical susceptibility measurements could be prepared by extrusion techniques from the benzobisthiazole polymer containing a monothiophene linkage. Degenerate four wave mixing measurements on this film yielded a third order optical susceptibility χ(3) of approximately 4.5 × 10?10 esu. © 1993 John Wiley & Sons, Inc. 相似文献