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31.
Hans Petersson 《Commentarii Mathematici Helvetici》1956,31(1):111-144
Ohne Zusammenfassung 相似文献
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Rothman DM Petersson EJ Vázquez ME Brandt GS Dougherty DA Imperiali B 《Journal of the American Chemical Society》2005,127(3):846-847
We present the chemical and biological synthesis of caged phosphoproteins using the in vitro nonsense codon suppression methodology. Specifically, phosphoamino acid analogues of serine, threonine, and tyrosine with a single photocleavable o-nitrophenylethyl caging group were synthesized as the amino acyl tRNA adducts for insertion into full-length proteins. For this purpose, a novel phosphitylating agent was developed. The successful incorporation of these bulky and charged amino acids into the alpha-subunit of the nicotinic acetyl choline receptor (nAChR) and the vasodilator-stimulated phosphoprotein (VASP) using an in vitro translation system is reported. 相似文献
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Production of single mesons and opposite side pairs of mesons in hadron-nucleus and nucleusnucleus collisions are calculated in the framework of the QCD parton model, with the assumption that quarks and gluons undergo multiple scattering in the nucleus. A comparison with all available data is made. It is also shown that the anomalous nuclear enhancement, especially its dependence on the flavour, can be quantitatively described within the model. Furthermore, we predict no enhancement for symmetric pairs as it seems to be indicated by the data. Predictions for largep T production in α?α scattering at ISR are made. 相似文献
36.
B. Petersson 《Journal of sound and vibration》1983,91(2):219-238
The problem of point excitation at a T-intersection of two perpendicular plates is studied in order to establish expressions for the point mobility. It is found that the theory for point excitation of the free surface of a semi-infinite elastic solid is applicable in the frequency range associated with structure-borne sound transmission. From this theory the mobility for an infinite system is derived. Based on this model and on an experimental investigation an estimation procedure for the point mobility in the finite dimension case is developed. The agreement with measurements performed in situ is quite acceptable. Both the theoretical and the experimental investigations reveal that the real part of this mobility is small, although it is larger in the experimental results. This indicates that other components of excitation are difficult to eliminate and may contribute to the power input in practice. Because of the small real part of the mobility it is advantageous with respect to the reduction of structure-borne sound power transmission to locate the contact points between a source and the receiver at such intersections. Corrections are deduced for the measured magnitude of the mobility for the case when separate force and motion transducers are used. 相似文献
37.
We provide a sorting algorithm, Adaptive Heapsort, that optimally adapts to several known, and new, measures of presortedness. The algorithm is motivated by a new measure, called Osc, which intuitively tells the oscillation within the input sequence. We show that Osc generalizes a number of measures appearing in the literature. Moreover, it has an interesting application in the sweepline technique in computational geometry. 相似文献
38.
We study quantum coherence in a semiconductor charge qubit formed from a GaAs double quantum dot containing a single electron. Voltage pulses are applied to depletion gates to drive qubit rotations and noninvasive state readout is achieved using a quantum point contact charge detector. We measure a maximum coherence time of ~7 ns at the charge degeneracy point, where the qubit level splitting is first-order insensitive to gate voltage fluctuations. We compare measurements of the coherence time as a function of detuning with numerical simulations and predictions from a 1/f noise model. 相似文献
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Simultaneous 2D flow velocity and gas temperature measurements using thermographic phosphors 总被引:1,自引:0,他引:1
In this paper a new approach for simultaneous 2D velocity and temperature measurements using phosphoric particles is presented.
The phosphoric particles respond to the temperature changes in the flow while acting as tracers for velocity mapping. The
temperature sensitive particles were seeded into a heated flow and were excited by a pulsed UV laser. The subsequent red shifted
emission was detected and analyzed to infer temperature using calibration procedures for lifetime and emission spectra against
temperature. The diameter of the temperature sensitive particles, usually in the range of 1–10 μm, makes them useful for velocity
measurements using particle image velocimetry (PIV). As such, simultaneous measurement of temperature and flow velocity of
a gaseous flow were performed and presented.
PACS 42.62.-b; 47.80.Cb; 47.80.Fg 相似文献