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61.
P.R. Willmott R. Herger M.C. Falub L. Patthey M. Döbeli C.V. Falub M. Shi M. Schneider 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1199-1201
A new ablation target geometry is presented that was used to produce thin films of La1-xSrxMnO3 grown heteroepitaxially on SrTiO3 by pulsed reactive crossed-beam laser ablation. The films were grown in order to perform angle-resolved photoelectron spectroscopy, which demands that the surface be atomically flat. In situ and ex situ analysis shows that this condition was met, even after depositing to a thickness of over 100 nm. PACS 61.10.-i; 61.18.Bn; 68.47.Gh; 71.27.+a; 81.15.Fg 相似文献
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Armin C. Schneider Christoph Pasel Michael Luckas Klaus Gerhard Schmidt Jan-Dirk Herbell 《Journal of solution chemistry》2004,33(3):257-273
The single ion activity coefficients of hydrogen and chloride ions in aqueous HCl solutions have been estimated at 25°C at concentrations up to 1 mol-kg–1, using potentiometric measurements with ion-selective electrodes and appropriate calibration procedures. Two methods are described for an internal calibration of the electrodes in the extended Debye–Hückel concentration range. The results are compared to the conventional pH calibration with external buffer solutions. Since the latter calibration method does not account for the liquid junction potential E
J which arises at the reference electrode, the resulting activity coefficients are quite different in HCl solutions of higher concentration. These differences between internal and external calibration decrease significantly, when a correction for E
J is introduced into the conventional pH calibration. Hence, in solutions of higher ionic strength the accuracy of the conventional pH electrode calibration using buffer solutions is very limited, when exact H+ activities are required. The consistency of the results indicates that the liquid junction potentials in the examined systems calculated by the Henderson/Bates approximation are of reasonable precision. 相似文献
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J. Feldhaus E. L. Saldin J. R. Schneider E. A. Schneidmiller M. V. Yurkov 《Optics Communications》1997,140(4-6):341-352
A new design for a single pass X-ray Self-Amplified Spontaneous Emission (SASE) FEL is proposed. The scheme consists of two undulators and an X-ray monochromator located between them. The first stage of the FEL amplifier operates in the SASE linear regime. After the exit of the first undulator the electron bunch is guided through a non-isochronous bypass and the X-ray beam enters the monochromator. The main function of the bypass is to suppress the modulation of the electron beam induced in the first undulator. This is possible because of the finite value of the natural energy spread in the beam. At the entrance to the second undulator the radiation power from the monochromator dominates significantly over the shot noise and the residual electron bunching. As a result the second stage of the FEL amplifier operates in the steady-state regime when the input signal bandwidth is small with respect to that of the FEL amplifier. Integral losses of the radiation power in the monochromator are relatively small because grazing incidence optics can be used. The proposed scheme is illustrated for the example of the 6 nm option SASE FEL at the TESLA Test Facility under construction at DESY. As shown in this paper the spectral bandwidth of such a two-stage SASE FEL (Δλ/λ 5 × 10−5) is close to the limit defined by the finite duration of the radiation pulse. The average brilliance is equal to 7 × 1024 photons/(s × mrad2 × mm2 × 0.1% bandw.) which is by two orders of magnitude higher than the value which could be reached by the conventional SASE FEL. The monochromatization of the radiation is performed at a low level of radiation power (about 500 times less than the saturation level) which allows one to use conventional X-ray optical elements (grazing incidence grating and mirrors) for the monochromator design. 相似文献
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An interval-parameter fuzzy linear programming method (IFMOLP) is proposed in this study for multiple objective decision-making
under uncertainty. As a hybrid of interval-parameter and fuzzy methodologies, the IFMOLP incorporates interval-parameter linear
programming and fuzzy multiobjective programming approaches to form an integrated optimization system. The method inherits
advantages of interval-parameter programming, and allows uncertainties and decision-makers’ aspirations to be effectively
communicated into its programming processes and resulting solutions. Membership functions for both objectives and constraints
are formulated to reflect uncertainties in different system components and their interrelationships. An interactive solution
procedure has been developed based on solution approaches of the interval-parameter and fuzzy programming techniques, plus
necessary measures for handling the multiobjective feature. A didactic example is provided in the paper to illustrate the
detailed solution process. Possibilities of further improvements by seeking Pareto optimum and incorporating flexible preference
within constraints are also discussed. 相似文献
69.
We respond to criticisms of our paper “The Free Will Theorem”, and produce a new form of the theorem based on weaker assumptions. 相似文献
70.