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61.
X-Ray photoelectron spectra of TiS3 with a one-dimensional structure were measured. TiS3 may be regarded as Ti4+(S2)2?S2? with pairs of S atoms (S2) and isolated S atoms. The spectra of the sulfur core-levels are assigned by comparison with those of TiS2, where all S atoms are largely separated. The binding energy of the S2 pairs is found to be 1.4 eV higher than that of the isolated S atoms, which is consistent with the larger negative charge of the isolated atoms. The structures of the valence band of TiS3 are discussed in terms of a molecular orbital scheme for the S2 pairs.  相似文献   
62.
We give an example of a space X with the property that every orientable fibration with the fiber X is rationally totally non-cohomologous to zero, while there exists a nontrivial derivation of the rational cohomology of X of negative degree.  相似文献   
63.
This paper is concerned with global stabilization of an undamped non‐linear string in the case where any velocity feedback is not available. The linearized system has an infinite number of poles and zeros on the imaginary axis. In the case where any velocity feedback is not available, a parallel compensator is effective. The stabilizer is constructed for the augmented system which consists of the controlled system and a parallel compensator. It is proved that the string can be stabilized by linear boundary control. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
64.
In this paper low‐gain adaptive stabilization of undamped semilinear second‐order hyperbolic systems is considered in the case where the input and output operators are collocated. The linearized systems have an infinite number of poles and zeros on the imaginary axis. The adaptive stabilizer is constructed by a low‐gain adaptive velocity feedback. The closed‐loop system is governed by a non‐linear evolution equation. First, the well‐posedness of the closed‐loop system is shown. Next, an energy‐like function and a multiplier function are introduced and the exponential stability of the closed‐loop system is analysed. Some examples are given to illustrate the theory. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
65.
In this note we give presentations, up to conjugacy, of all finite subgroups of the mapping class group of a closed surface of genus 2, using the Humphries generators. An application to homology representations is given.  相似文献   
66.
We give a unified method to obtain the conservativeness of a class of Markov processes associated with lower bounded semi-Dirichlet forms on L 2(X;m), including symmetric diffusion processes, some non-symmetric diffusion processes and jump type Markov processes on X, where X is a locally compact separable metric space and m is a positive Radon measure on X with full topological support. Using the method, we give an example in each section, providing the conservativeness of the processes, that are given by the “increasingness of the volume of some sets(balls)” and “that of the coefficients on the sets” of the Markov processes.  相似文献   
67.
Journal of Theoretical Probability - We consider symmetric stable-type processes with degenerate/singular Lévy densities via Dirichlet form theory. We give conditions of some global path...  相似文献   
68.
A low‐dilution, undersized (12.5 mm diameter) glass–bead technique was developed for X‐ray fluorescence determination of 34 components (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, Fe2O3, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Cs, Ba, La, Pr, Nd, Sm, Gd, Dy, Er, Yb, Hf, W, and Pb) in precious silicic samples for geochemistry and archeology. This preparation was consolidated based on the properties of the specimen, including disk formability and detachability from a small crucible, through variation of the amounts of the two samples (basaltic and granitic rocks) and releasing reagent. The specimen was prepared by fusing a mixture of 200 mg of powdered sample, 200 mg of lithium tetraborate as a flux, and 60 µl of 18.42 mass% lithium chloride solution as a releasing agent in a small platinum crucible. Calibration curves were drawn using synthetic calibration standards, which were prepared by compounding chemical reagents, such as oxides, carbonates, and diphosphates containing analytes. The calibration curves showed good linearity with correlation coefficient values greater than 0.990. Using the proposed method, we determined 34 components in five igneous rock reference samples. The results were in agreement with the recommended values, accounting for uncertainties. With this method, preparation requires only small amounts of the powdered sample and alkali flux; however, still allowing for determination of many analytes, which is advantageous when dealing with limited quantities of precious samples. The present method has potential applications in the chemical characterization of various geological and archeological samples. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
69.
Discrete Gamow-Teller (GT) transitions 176Yb-->176Lu at low excitation energies have been measured via the ( 3He,t) reaction at 450 MeV and at 0 degrees. For 176Yb, two low-lying states are observed, setting low thresholds Q(nu) = 301 and 445 keV for neutrino ( nu) capture. Capture rates estimated from the measured GT strengths, the simple two-state excitation structure, and the low Q(nu) in Yb-Lu indicate that Yb-based nu detectors are well suited for a direct measurement of the sub-MeV solar electron-neutrino ( nu(e)) spectrum including pp neutrinos.  相似文献   
70.
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