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31.
Shaw NM Blanis D Bodek A Budd H Coombes R Eno S Fry CA Harada H Ho YH Kim YK Kumita T Mori T Olsen SL Sill A Thorndike EH Ueno K Zheng HW Imlay R Kirk P Lim J McNeil RR Metcalf W Myung SS Cheng CP Gu P Li J Li YK Mao ZP Xu YT Zhu YC Abashian A Gotow K Hu K Low EH Mattson ME Naito F Piilonen L Sterner KL Lusin S Rosenfeld C Wang AT Wilson S Frautschi M Kagan H Kass R Trahern CG Breedon RE Kim GN Ko W Lander RL Maeshima K Malchow RL Smith JR Sparks K Williams MC Abe K Fujii Y Higashi Y Kim SK 《Physical review letters》1989,63(13):1342-1345
32.
L. de Arcangelis H. J. Herrmann M. Kolb René Thomas C. Amitrano L. Peliti M. Saber G. Weisbuch Sara A. Solla F. Bagnoli A. Francescato R. Livi S. Ruffo Pablo Tamayo Michel Droz Peter Jörg Plath S. Romano Yves Pomeau Stéphane Zaleski D. Stauffer Luciano R. da Silva Alex Hansen Stéphane Roux Antonio Coniglio B. Derrida Henrik Flyvbjerg Naeem Jan Dietrich Stauffer Peter Grassberger A. Zippelius K. E. Kurten Werner Krauth Jean -Pierre Nadal Marc Mézard Per Bak Chao Tang Itzhak Webman M. L. Martins H. F. V. Resende C. Tsallis A. C. N. Magalhaes 《Journal of statistical physics》1989,55(5-6):1333-1359
33.
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
34.
The electronic structure and the electron dynamics of the clean InAs(1 1 1)A 2 × 2 and the InAs(1 1 1)B 1 × 1 surfaces have been studied by laser pump-and-probe photoemission spectroscopy. Normally unpopulated electron states above the valence band maximum (VBM) are filled on the InAs(1 1 1)A surface due to the conduction band pinning above the Fermi level (EF). Accompanied by the downward band banding alignment, a charge accumulation layer is confined to the surface region creating a two dimensional electron gas (2DEG). The decay of the photoexcited carriers above the conduction band minimum (CBM) is originated by bulk states affected by the presence of the surface. No occupied states were found on the InAs(1 1 1)B 1 × 1 surface. This fact is suggested to be due to the surface stabilisation by the charge removal from the surface into the bulk. The weak photoemission intensity above the VBM on the (1 1 1)B surface is attributed to electron states trapped by surface defects. The fast decay of the photoexcited electron states on the (1 1 1)A and the (1 1 1)B surfaces was found to be τ1 1 1 A ? 5 ps and τ1 1 1 B ? 4 ps, respectively. We suggest the diffusion of the hot electrons into the bulk is the decay mechanism. 相似文献
35.
Optical waveguide sensor for on-line monitoring of bacteria 总被引:2,自引:0,他引:2
A grating-coupled planar optical waveguide sensor is presented for sensing of bacteria by evanescent waves. The waveguide design results in increased depth of penetration into the sample volume, which makes it suitable for detecting micrometer-sized biological objects. We tested the sensor's performance by monitoring the adhesion of Escherichia coli K12 cells to the sensor surface. 相似文献
36.
This paper demonstrates a method to determine the bidirectional transmittance distribution function (BTDF) using an integrating sphere. Information about the sample’s angle-dependent scattering is obtained by making transmittance measurements with the sample at different distances from the integrating sphere. Knowledge about the illuminated area of the sample and the geometry of the sphere port in combination with the measured data combines to a system of equations that includes the angle-dependent transmittance.The resulting system of equations is an ill-posed problem which rarely gives a physical solution. A solvable system is obtained by using Tikhonov regularization on the ill-posed problem. The solution to this system can then be used to obtain the BTDF.Four bulk-scattering samples were characterised using two goniophotometers and the described method to verify the validity of the new method. The agreement shown is excellent for the more diffuse samples. The solution to the low-scattering samples contains unphysical oscillations, but still gives the correct shape of the solution. The origin of the oscillations and why they are more prominent in low-scattering samples are discussed. 相似文献
37.
A new hybrid magnetic bead separator that combines an external magnetic field with 175 μm thick current lines buried in the back side of a silicon wafer is presented. A microfluidic channel was etched into the front side of the wafer. The large cross-section of the current lines makes it possible to use larger currents and obtain forces of longer range than from thin current lines at a given power limit. Guiding of magnetic beads in the hybrid magnetic separator and the construction of a programmable microarray of magnetic beads in the microfluidic channel by hydrodynamic focusing is presented. 相似文献
38.
We show that reductions of KP hierarchies related to the loop algebra of SLn with homogeneous gradation give solutions of the Darboux-Egoroff system of PDE's. Using explicit dressing matrices of the Riemann-Hilbert problem generalized to include a set of commuting additional symmetries, we construct solutions of the Witten– Dijkgraaf–E. Verlinde–H. Verlinde equations. 相似文献
39.
A coherent anti-Stokes Raman scattering microscope based on a Ti:sapphire femtosecond oscillator and a photonic crystal fiber is demonstrated. The nonlinear response of the fiber is used to generate the additional wavelength needed in the Raman process. The applicability of the setup is demonstrated by imaging of micrometer-sized polystyrene beads. 相似文献
40.
Contrasts between beta relaxation in equilibrium viscous liquids and glasses are rationalized in terms of a double-well potential model with structure-dependent asymmetry, assuming structure is described by a single order parameter. The model is tested for tripropylene glycol where it accounts for the hysteresis of the dielectric beta loss peak frequency and magnitude during cooling and reheating through the glass transition. 相似文献