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131.
Baker KL Stappaerts EA Gavel D Wilks SC Tucker J Silva DA Olsen J Olivier SS Young PE Kartz MW Flath LM Kruelevitch P Crawford J Azucena O 《Optics letters》2004,29(15):1781-1783
Results of atmospheric propagation for a high-speed, large-actuator-number adaptive optics system are presented. The system uses a microelectromechanical system- (MEMS-) based spatial light modulator correction device with 1024 actuators. Tests over a 1.35-km path achieved correction speeds in excess of 800 Hz and Strehl ratios close to 0.5. The wave-front sensor was based on a quadrature interferometer that directly measures phase. This technique does not require global wave-front reconstruction, making it relatively insensitive to scintillation and phase residues. The results demonstrate the potential of large-actuator-number MEMS-based spatial light modulators to replace conventional deformable mirrors. 相似文献
132.
133.
Back BB Baker MD Ballintijn M Barton DS Becker B Betts RR Bickley AA Bindel R Budzanowski A Busza W Carroll A Decowski MP García E Gburek T George N Gulbrandsen K Gushue S Halliwell C Hamblen J Harrington AS Henderson C Hofman DJ Hollis RS Hołyński R Holzman B Iordanova A Johnson E Kane JL Khan N Kulinich P Kuo CM Lee JW Lin WT Manly S Mignerey AC Noell A Nouicer R Olszewski A Pak R Park IC Pernegger H Reed C Remsberg LP Roland C Roland G Sagerer J Sarin P Sawicki P Sedykh I Skulski W Smith CE 《Physical review letters》2003,91(7):072302
We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25
相似文献
134.
A new strategy for the combinatorial synthesis of new materials has been developed through the consecutive application of an Ugi 4CC reaction and a ring-opening metathesis polymerization (ROMP) reaction. Norbornenyl aldehydes and carboxylic acids could be used in the Ugi MCR to give highly diverse monomers that were converted to the corresponding polymers by exposure to the second-generation Grubbs' catalyst. These polymers have structural features reminiscent of polypeptides and the process could be extended to the preparation of chiral materials. 相似文献
135.
Ice nucleating-active Pseudomonas fluorescens F264C was fed to Colorado potato beetles to determine bacterial retentioin in the beetle gut and its effect on the cold hardiness of this insect pest. The bacrterium was present in beetles recovered after overwintering in the field, seven months after their exposure to P. fluorescens. Retention was evident not only in the detection of the P. fluorescens ice nucleating gene, inaW, in bacterial cultures from beetle guts but also in the elevated supercooling points of some treated beetles. 相似文献
136.
Kylstra NJ Worthington RA Patel A Knight PL Vazquez De Aldana JR Roso L 《Physical review letters》2000,85(9):1835-1838
An analysis of the influence of the magnetic field of an intense, high-frequency laser pulse on the stabilization of an atomic system is presented. We demonstrate that at relatively modest intensities the magnetic field can significantly alter the dynamics of the system. In particular, a breakdown of stabilization occurs, thereby restricting the intensity regime in which the atom is relatively stable against ionization. Counterpropagating pulses do not negate the detrimental effects of the magnetic field. We compare our quantum mechanical results with classical Monte Carlo simulations. 相似文献
137.
Smith JG Alexander JP Baker R Bebek C Berger BE Berkelman K Blanc F Boisvert V Cassel DG Dickson M Drell PS Ecklund KM Ehrlich R Foland AD Gaidarev P Gibbons L Gittelman B Gray SW Hartill DL Heltsley BK Hopman PI Jones CD Kreinick DL Lohner M Magerkurth A Meyer TO 《Physical review letters》2000,84(7):1393-1397
We present the first observation of the decay B-->J/psistraight phiK. Using 9.6x10(6) B&Bmacr; meson pairs collected with the CLEO detector, we have observed ten fully reconstructed B-->J/psistraight phiK candidates, whereas the estimated background is 0.5+/-0.2 event. We obtain a branching fraction of B(B-->J/psistraight phiK) = (8. 8(+3.5)(-3.0)[stat]+/-1.3[syst])x10(-5). This is the first observed B meson decay requiring the creation of an additional s&smacr; quark pair. 相似文献
138.
Peter Sörös Jonathan Marmurek Fred Tam Nicole Baker W Richard Staines Simon J Graham 《BMC neuroscience》2007,8(1):48
Background
Focal lesions of the frontal, parietal and temporal lobe may interfere with tactile working memory and attention. To characterise the neural correlates of intact vibrotactile working memory and attention, functional MRI was conducted in 12 healthy young adults. Participants performed a forced-choice vibrotactile frequency discrimination task, comparing a cue stimulus of fixed frequency to their right thumb with a probe stimulus of identical or higher frequency. To investigate working memory, the time interval between the 2 stimuli was pseudo-randomized (either 2 or 8 s). To investigate selective attention, a distractor stimulus was occasionally presented contralaterally, simultaneous to the probe. 相似文献139.
140.
Matthew H. Baker 《Proceedings of the American Mathematical Society》1999,127(10):2851-2856
This paper gives a new proof of Kamienny's Criterion using the method of Coleman and Chabauty.