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131.
Aledealat K Mihajlović G Chen K Field M Sullivan GJ Xiong P Chase PB von Molnár S 《Journal of magnetism and magnetic materials》2010,322(24):L69-L72
We report integration of an InAs quantum well micro-Hall magnetic sensor with microfluidics and real-time detection of moving superparamagnetic beads. Beads moving within and around the Hall cross area result in positive and negative Hall voltage signals, respectively. Relative magnitudes and polarities of the signals measured for a random distribution of immobilized beads over the sensor are in good agreement with calculated values and explain consistently the shape of the dynamic signal. 相似文献
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A series of bridged triarylamines, which constitute a new class of heterohelicenes, have been synthesized using a simple three-step procedure. These compounds are shown to be highly luminescent chromophores and are capable of being oxidized. The solid-state structures of these helicenes show a tendency for pi-stacking interactions into an overall zigzag motif. 相似文献
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The known acid (F3C)2CC(NHCOPh)CO2H was more fully characterized (the neutralization equivalent was one-fifth the molecular weight). Thioacetic acid did not react with it. Efforts to effect conjugate addition of -toluenethiol led with piperidine only to intractable mixtures and with BF3·Et2O only to the thiol ester. Without catalyst, addition occurred but in the reverse sense to give 2-benzamido-2-benzylthio-3-trifluoromethyl-4,4,4-trifluorobutanoic acid. The latter was reduced by metals in liquid ammonia only to a red non-sulfur polymer but was reductively desulfurized by HBr/AcOH to 2-benzamido-3-trifluoromethyl-4,4,4-trifluorobutanoic acid (two crystalline forms). 相似文献
137.
Polyacrylamide-filled gel columns are used to separate oligonucleotide samples. For homopolymeric standard samples, plots of migration time versus molecular size are presented over a range of 30-160 bases. With 2.5-4% T and 3.3% C gels, good resolution over the examined mass range, with peak width at half height of 3 to 6 s, is obtained by applying electrical fields of 200-400 V/cm. The separation of heteropolymeric nucleotides by slab gel electrophoresis under routine conditions was compared with capillary gel electrophoresis. Using the same column and the same separation conditions, the plot of migration time versus base number is linear with an identical slope for three oligonucleotide samples which were examined, allowing a calibration of a gel-filled capillary for molecular mass determination. 相似文献
138.
Sub-Doppler optical-optical double-resonance excitation spectra of BaF were recorded using two single-mode cw dye lasers. In the 30 000-cm?1 region, the electronic states observed were E2Σ+ and F2Π. The latter had been previously assigned as the “F2Σ+” state by Fowler [Phys. Rev.59, 645–652 (1941)]. The (3, 0) and (4, 0) bands of the E2Σ+-B2Σ+ transition and the (1, 0) and (2, 0) bands of the F2Π-B2Σ+ transition were rotationally analyzed. The molecular constants suggest inferences about the dominant atomic orbital character of the Rydberg molecular orbitals responsible for the E2Σ+ and F2Π electronic states. A new electronic state, the , is predicted. The molecular parameters obtained (in cm?1, 1σ uncertainty in parentheses) are
3 | 29 767.32(1) | 1 | 29 997.29(1) | |
3 | 522.841(27) | 1 | 522.553(2) | |
0.22990(22) | 0.22931(8) | |||
0.00113(14) | 0.00108(2) | |||
1 | 56.9840(12) | |||
1 | ?0.02426(6) | |||
3 | ?0.17367(46) |
0 | 15 958.41 (10) | 16 383.137 (6) | |
285.732 (9) | 288.56 (20) | 285.747 (9) | |
0.840 (4) | — | 0.954 (4) | |
0.094466141 (30) | 0.0957343 (20) | 0.0965151 (20) | |
0.000403551 (40) | 0.0004327 (20) | 0.0004483 (15) | |
(spin-rot.) | 0.00301484 (50) | — | 0.068767 (79) |
— | ?0.066834 (64) | — | |
— | 59.175 (1) | — |
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