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101.
B. Curtis Eaves 《Mathematical Programming》1990,48(1-3):359-367
Subdivisions are continuously deformed subject to three local conditions and shown to retain the global property of being a subdivision. Cell maps, which are introduced, enable elementary arguments.This research is supported in part by the National Science Foundation Grant DMS-8902662. 相似文献
102.
J. M. Curtis P. J. Derrick J. Holgersson B. E. Samuelsson M. E. Breimer 《Journal of the American Society for Mass Spectrometry》1992,3(4):353-359
A permethylated-reduced hexaglycosylceramide in a complex glycolipid mixture isolated from a unique human tissue has been identified by using tandem mass spectrometry (MS/MS). The mass spectrum of this glycolipid mixture, obtained by using in-beam electron ionization, is very complex, and fragment ions derived from the hexaglycosylceramide cannot be distinguished from other ions. Tandem mass spectrometry using a four-sector mass spectrometer gave the mass spectrum of the immonium ion of the permethylated-reduced hexaglycosykeramide (m / z 1645.8), which is characteristic of its structure. Comparison of this MS/MS spectrum with those of two similarly derivatized blood group hexaglycosylceramide isomers permitted identification of the unknown glycolipid structure. 相似文献
103.
104.
105.
Givenf: R
n
R
n*
with some conditions, our aim is to compute a fixed pointx f(x) off; hereR
n
isn-dimensional Euclidean space andR
n*
is the collection of nonempty subsets ofR
n
. A typical application of the algorithm can be motivated as follows: Beginning with the constant mapf
0:R
n
{0} R
n
and its fixed pointx
0 = 0, we deformf
t
ast tof
f and follow the pathx
t
of fixed points off
t
. Cluster points of thex
t
's ast are fixed points off.
This research was supported in part by Army Research Office-Durham Contract DAHC-04-71-C-0041 and by National Science Foundation Grant GK-5695. 相似文献
106.
Ruthenium shows promise for use as a chemical modifier for the determination of ultratrace quantities of lead in solution when compared with the popular and widely used palladium. There is experimental evidence that ruthenium reacts with lead in the graphite tube to form the intermetallic compound PbRu2. The amount of ruthenium had a dramatic effect on the absorbance profile for the lead signal. 相似文献
107.
108.
Lines of the 3ν23 “forbidden” band of 12C16O2 have been identified in the 2000-cm?1 region of a long-path, 0.01-cm?1 resolution laboratory absorption spectrum. This band has detectable intensity due to Δl = 2 Fermi interactions between the upper level and the nearby ν1 + ν2 and 3ν21 levels. Intensities of 18 lines of this band have been measured using a nonlinear least-squares spectral fitting technique. The intensities are enhanced at high J and an expression for the intensity distribution as derived by Toth [Appl. Opt.23, 1825–1834 (1984)] is used for the analysis. In terms of the total sample pressure, the vibrational band intensity is 0.194 ± 0.008 × 10?30 cm?1/molecule-cm?2 at 296 K. The coefficient in the F factor is analogous to the Coriolis coefficient ξ and has been determined to be ?0.0413 ± 0.0015. As expected by theory, its value is very close to that of ξ for the related ν1 + ν2 band. 相似文献
109.
110.
The melting points, vapour pressures and heats of sublimation of the complexes of Ga, In, Y, La, Gd, Fe, Zn, Pb and Li with 2,2,6,6-tetramethyl-3,5-heptanedione are reported for the temperature range below the melting point of 40? to 250?C and pressures from 10 to 10?2 torr. The measurements were made with an easily constructed Knudsen effusion cell in conjunction with a Mettler thermobalance. 相似文献