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351.
Gerhard Dziuk John E. Hutchinson 《Calculus of Variations and Partial Differential Equations》1996,4(1):27-58
We prove optimal convergence results for discrete approximations to (possibly unstable) minimal surfaces. This appears to be the first class of results of this type for geometric objects solving a highly non-linear geometric variational problem. We introduce a number of new techniques which we expect will be of use in other geometric problems. The theoretical approximation results are confirmed by numerical test computations. 相似文献
352.
353.
1H and 13C n.m.r. data indicate that bilirubin azopigments exist predominantly as phenylhydrazone rather than azobenzene tautomers. Whereas 0-lactim ethers derived from the azopigments exist predominantly as the azobenzene tautomers. 相似文献
354.
R. Stroynowski D. Blockus W. Dunwoodie D.W.G.S. Leith M. Marshall C.L. Woody B. Barnett C.Y. Chien T. Fieguth M. Gilchriese D. Hutchinson W.B. Johnson P. Kunz T. Lasinski L. Madansky W.T. Meyer A. Pevsner S. Williams 《Physics letters. [Part B]》1980,97(2):315-319
The production of prompt electron-positron pairs in 16 GeV/c π-p collisions has been measured using the LASS spectrometer at SLAC. An excess of events is observed above the estimated contribution of direct and Dalitz decays of known resonances in the kinematic range defined by and . The excess signal decreases slowly with increasing M, but exhibits very steep χ and pT2 dependence. 相似文献
355.
The structure parameter x (also known as the nonlinearity parameter), which in the KAHR model determines the relative contributions of temperature and structure to the retardation times of polymers in the glass transition region, is evaluated experimentally for a narrow molecular weight fraction of atactic polystyrene by the peak-shift method. This method is based on the dependence on heating rate and annealing time of the endothermal peak temperatures Tp, obtained by differential scanning calorimetry during the heating stage of well-defined three-step thermal cycles. The results obtained from the shifts of Tp, with both heating rate and the amount of isothermal recovery during the annealing stage before reheating, are consistent with the theoretical predictions of the KAHR model. The appropriate analysis of the data for a polystyrene fraction of molecular weight 30,100 leads to a value of x = 0.46 ± 0.02. Furthermore, this value of x is constant for a wide range of annealing times and heating rates and for two different annealing temperatures, in full agreement with the theoretical model. The advantages of the peak-shift method over that used by most other workers, the curve-fitting method, are critically discussed. 相似文献
356.
357.
Jamil Baghdadchi Albert P. Chan James H. Hutchinson 《Journal of heterocyclic chemistry》1988,25(3):973-974
The products obtained from the reaction of p-methyl- and p-methoxyphenacyl bromide with various bases are described. 相似文献
358.
359.
A terahertz half-cycle pulse was used to retrieve information stored as quantum phase in an N-state Rydberg atom data register. The register was prepared as a wave packet with one state phase reversed from the others (the "marked bit"). A half-cycle pulse then drove a significant portion of the electron probability into the flipped state via multimode interference. 相似文献
360.
Tricarbonyl(eta 5-cyclohexadienyl)iron(0) and dicarbonyl(triphenylphosphine)(eta 5-cyclo-hexadienyl)iron(0) were derivatized by attachment of an aminopropylsilyl link and covalently attached to fumed silica particles. The fumed silica was coated onto the ZnSe element of an attenuated total reflection (ATR) cell for Fourier transform infrared (FTIR) spectroscopic analysis. The immobilized organometalcarbonyl probe groups are shown to retain their capacity to function as a key element of a molecular sensor assembly and the nu(CO) bands of the two probe groups were interrogated to calibrate the responses for 0-5% levels of dodecane in cyclohexanol to within +/- 0.1%. The potential for dual sensing is described and the simultaneous monitoring of two discrete regions of a dynamically varying inhomogeneous system is reported for the determination of dodecane in cyclohexanol as solutions mix across a permeable barrier in the ATR cell. 相似文献