Determination of Phosphorus in Low-Alloy Steels by Charged-Particle Activation Analysis

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Determination of P, Cl, K and Ca in Several Control Serums by Alpha-Particle Activation Analysis Applying the New Internal Standard Method Coupled with the Standard Addition Method

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Determination of Strontium in Biological Materials by Charged Particle Activation Analysis using the Stable-isotope Dilution Method

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Influence of carrier-carrier and carrier-phonon correlations on optical absorption and gain in quantum-dot systems

A microscopic theory is used to study the optical properties of semiconductor quantum dots. The dephasing of a coherent excitation and line-shifts of the interband transitions due to carrier-carrier Coulomb interaction and carrier-phonon interaction are determined from a quantum kinetic treatment of correlation processes. We investigate the density dependence of both mechanisms and clarify the importance of various dephasing channels involving the localized and delocalized states of the system.Comment: 12 pages, 10 figure

Invar-Type New Ferromagnetic Amorphous Fe-B Alloys(Physics)

Measurements of magnetization, electrical resistivity, thermal expansion and differential thermal change were made on amorphous Fe_B_x (9≦X≦21) alloys prepared by rapid quenching from the liquid state. With decreasing boron content in the alloys, the Curie temperature falls remarkably, while the magnetic moment increases sluggishly. The thermal expansion curves exhibit the invar characteristics below the Curie temperature due to a large positive spontaneous volume magnetostriction, and the reduced magnetization curves decrease much more rapidly with increasing temperature than those of other ferromagnetic amorphous alloys

Time-of-Flight Pulsed Neutron Diffraction of Pd_<0.8>-Si_<0.2> Amorphous Alloy Using the Electron Linac

The structure factor S(Q) of Pd_-Si_ amorphous alloy was measured over wide range of Q (=4π sin θ/λ) up to 40 A^ by time-of-flight neutron diffraction using pulsed epithermal-neutron generated from the Tohoku University electron linac. The S(Q) has definitely shown an oscillation even in range of Q≳25 A^. The 1st peak of the pair distribution function Fourier transformed from the S(Q) has been split into two sub-peaks at the position of 2.42 and 2.81 A. Combining the neutron result with the X-ray result, the 1st sub-peak was verified to correspond to Pd-Si pair and the 2nd sub-peak the mixture of Pd-Pd pair and Pd-Si pair where Pd atom was substituted with Si atom. The average numbers of the nearest neighbour atoms around the Pd atom at origin are 1.7 Si atoms in the 1st sub-peak and 10.7 Pd and 1.5 Si atoms in the 2nd sub-peak. There may be no Si-Si pair with the nearest interatomic distance in the alloy. Such a relation for atom-atom pairs is found in the crystalline Pd_3Si compound, too. The liquid structure of the alloy was also measured and concluded to be essentially close to the amorphous structure except more blurring of peaks

Structural Study of an Amorphous Bi-Fe-Ca-O Thin Film by the Anomalous X-ray Scattering

The structure of the amorphous Bi-Fe-Ca-O film with 0.3 m thick grown on the Si single crystal was studied by the anomalous x-ray scattering (AXS) method. This relatively new method using the anomalous dispersion effect of a specific constituent element in a film reduces the difficulty in the subtraction process of a substrate intensity for estimating the net intensity of a thin film, which becomes a main cause of errors of the resultant data in the conventional method. The environmental radial distribution functions around Bi and Fe in the amorphous Bi-Fe-Ca-O film were determined, from which the structural features were obtained