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141.
An apparatus and the procedure for cellulose acetate isoelectric focusing were refined and optimized for routine use in clinical laboratories. The space in the electrophoretic chamber was minimized to maintain high humidity during the run. The water content of the thin cellulose acetate membranes in the chamber was well controlled during isoelectric focusing and the effect of atmospheric carbon dioxide was also excluded. The temperature of the membranes was kept below 2 degrees C, even under conditions of high electric field strength for faster isoelectric focusing of high-molecular-weight proteins. No special training was required for technicians in clinical laboratories to obtain reproducible isoelectric profiles of human serum proteins. 相似文献
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The preparation and photorearrangement of vinyl cyclopropanes 2a–c and pyrazolines 3a and 3c are presented. 相似文献
144.
R.S. Eng P.L. Kelley A. Mooradian A.R. Calawa T.C. Harman 《Chemical physics letters》1973,19(4):524-528
The present results confirm earlier tunable laser observations that the atmospheric widths of high rotational energy transitions are considerably narrower than previously predicted. Intensities, self-broadening coefficients, nitrogen and air shifts, and relative positions have also been measured. 相似文献
145.
The self-broadened and nitrogen-broadened absorption profiles of the Q-branch head of the 1000 ← 0110 band of CO2 near 618 cm?1 were studied under high resolution (~10?4 cm?1) using tunable diode laser techniques. The intensity and linewidth of several lines in this Q branch, the ν2 band, 10.4-μm and 9.4-μm laser bands have been measured accurately. The lineshape of a CO2 line has also been measured to be Lorentzian within experimental accuracy to about 15 half-widths. Preliminary calculated Q-branch head absorption profiles agree reasonably well with the observed profiles. 相似文献
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Chen W Zhang HL Xu H Tok ES Loh KP Wee AT 《The journal of physical chemistry. B》2006,110(43):21873-21881
A SiC nanomesh is used as a nanotemplate to direct the epitaxy of C60 molecules. The epitaxial growth of C60 molecules on SiC nanomesh at room temperature is investigated by in situ scanning tunneling microscopy, revealing a typical Stranski-Krastanov mode (i.e., for the first one or two monolayers, it is a layer-by-layer growth or 2-D nucleation mode; at higher thicknesses, it changes to island growth or a 3-D nucleation mode). At submonolayer (0.04 and 0.2 ML) coverage, C60 molecules tend to aggregate to form single-layer C60 islands that mainly decorate terrace edges, leaving the uncovered SiC nanomesh almost free of C60 molecules. At 1 ML C60 coverage, a complete wetting layer of hexagonally close-packed C60 molecules forms on top of the SiC nanomesh. At higher coverage from 4.5 ML onward, the C60 stacking adopts a (111) oriented face-centered-cubic (fcc) structure. Strong bright and dim molecular contrasts have been observed on the first layer of C60 molecules, which are proposed to originate from electronic effects in a single-layer C60 island or the different coupling of C60 molecules to SiC nanomesh. These STM molecular contrast patterns completely disappear on the second and all the subsequent C60 layers. It is also found that the nanomesh can be fully recovered by annealing the C60/SiC nanomesh sample at 200 degrees C for 20 min. 相似文献