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211.
A variety of jumps has in the past been identified in diffusion of atoms on 1D channeled surfaces. To establish the jump processes important in diffusion on a 2D surface, the movement of individual Pd atoms has been examined on W(110). From the distribution of displacements of Pd at high temperatures, double jumps are found along the close-packed <111>. For the first time, sizable differences are also observed between the mean-square displacements along x and y, which demonstrate unexpected contributions from jumps along <110>, but not along <001>. These jumps proceed over activation barriers higher than for single jumps, under conditions predicted from previous work with Pd on the channeled W(211).  相似文献   
212.
Blood analysis by Raman spectroscopy   总被引:1,自引:0,他引:1  
Concentrations of multiple analytes were simultaneously measured in whole blood with clinical accuracy, without sample processing, using near-infrared Raman spectroscopy. Spectra were acquired with an instrument employing nonimaging optics, designed using Monte Carlo simulations of the influence of light-scattering-absorbing blood cells on the excitation and emission of Raman light in turbid medium. Raman spectra were collected from whole blood drawn from 31 individuals. Quantitative predictions of glucose, urea, total protein, albumin, triglycerides, hematocrit, and hemoglobin were made by means of partial least-squares (PLS) analysis with clinically relevant precision (r(2) values >0.93). The similarity of the features of the PLS calibration spectra to those of the respective analyte spectra illustrates that the predictions are based on molecular information carried by the Raman light. This demonstrates the feasibility of using Raman spectroscopy for quantitative measurements of biomolecular contents in highly light-scattering and absorbing media.  相似文献   
213.
214.
Within the framework of the minimal non-minimal supersymmetric standard model (MNMSSM) with tadpole terms, CP violation effects in the Higgs sector are investigated at the one-loop level, where the radiative corrections from the loops of the quark and squarks of the third generation are taken into account. Assuming that the squark masses are not degenerate, the radiative corrections due to the stop and sbottom quarks give rise to CP phases which trigger the CP violation explicitly in the Higgs sector of the MNMSSM. The masses, the branching ratios for dominant decay channels, and the total decay widths of the five neutral Higgs bosons in the MNMSSM are calculated in the presence of explicit CP violation. The dependence of these quantities on the CP phases is quite recognizable, for given parameter values.  相似文献   
215.
New phase formation at the La0.9Sr0.1MnO3/YSZ interface and its effects on the cathodic performances were studied at 900 °C in air. The resistance caused by the interfacial product layer kept increasing with time to reach up to 40% of the total resistance after 500 h. The interfacial product was identified as La2Zr2O7 by XRD measurement. The electrical conductivity of La2Zr2O7 (2.4 × 10−5 S cm−1 at 1000 °C), measured by AC impedance and current interruption methods, was 4 to 7 orders of magnitude smaller than those of La0.9Sr0.1MnO3 electrode or YSZ electrolyte. Either the electronic conductivity or the electrochemical O2 reduction activity of La2Zr2O7 was negligible. Combining these results, a conclusion was made that the cathodic degradation comes mainly from the growth of interfacial product layer and its contribution to the cell resistance increment is ohmic in nature.  相似文献   
216.
Summary A small experiment, ?MiniMax?, has been set up in the C0 intersection region of the Fermilab Tevatron to seek evidence for disoriented chiral condensates and to study other forward physics phenomena. The experiment consists of a proportional wire chamber telescope accompanied by scintillation (trigger) counters, a lead converter, and followed by an electromagnetic calorimeter. The solid angle accepted is a cone centered at pseudorapidity (η) of 4.1 and of radius (in η-ϕ space) of about 0.6. Over 2.5 million events thus far have demonstrated the successful operation of the apparatus, however to date the analysis has not progressed sufficiently to permit any conclusions concerning disoriented chiral condensates. presented byL. W. Jones Paper presented at the Special Session on very high-energy cosmic-ray interactions (superfamilies) of the XXIV International Cosmic-Ray Conference, Rome, August 28–September 8, 1995.  相似文献   
217.
Results are presented from a search for a ρ0ρ0 enhancement in antiproton annihilations. A ρ0ρ0 resonance was recently observed in radiative ψ decays, and its existence has been supported by the results of an antiproton experiment at 5.7 GeV/c. No indication of this ρ0ρ0 enhancement is seen is our data, in direct contradiction with the earlier, lower statistics experiment.  相似文献   
218.
It is shown that every almost *-homomorphism h : A→B of a unital JC*-algebra A to a unital JC*-algebra B is a *-homomorphism when h(rx) = rh(x) (r 〉 1) for all x∈A, and that every almost linear mapping h : A→B is a *-homomorphism when h(2^nu o y) - h(2^nu) o h(y), h(3^nu o y) - h(3^nu) o h(y) or h(q^nu o y) = h(q^nu) o h(y) for all unitaries u ∈A, all y ∈A, and n = 0, 1,.... Here the numbers 2, 3, q depend on the functional equations given in the almost linear mappings. We prove that every almost *-homomorphism h : A→B of a unital Lie C*-algebra A to a unital Lie C*-algebra B is a *-homomorphism when h(rx) = rh(x) (r 〉 1) for all x ∈A.  相似文献   
219.
When prior partial information about a state to be cloned is available, it can be cloned with a fidelity higher than that of universal quantum cloning. We experimentally verify this intriguing relationship between the cloning fidelity and the prior information by reporting the first experimental optimal quantum state-dependent cloner, using nuclear magnetic resonance techniques. Our experiments may further cast important implications into many quantum information processing protocols.  相似文献   
220.
Jung Y  Lee SB  Lee JW  Oh K 《Optics letters》2005,30(1):84-86
We report a bandwidth variation technique in an acousto-optic filter. Utilizing the adiabatic conversion in both optical and acoustic modes, we obtain a novel hybrid waveguide composed of serial concatenation of single-mode fiber (SMF) and two-mode hollow optical fiber (HOF). On the basis of dissimilarity in the phase-matching conditions and beat-length dispersion in SMF and HOF, the FWHM of the resonant bands is varied from 3.8 to 190 nm near the 1.5-microm region in a single device. Furthermore, we theoretically analyze the acousto-optic coupling among the guided modes in HOF, which shows good agreement with experimental observations.  相似文献   
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