Composition range of binary amorphous alloys

We have studied a number of binary metal-metal and metalloid alloy systems made by a single vapor-quench method under very consistent conditions. In each case, amorphous alloys are found in one continuous composition range (xmin≤x≤xmax) regardless of the number of eutectic points in the equilibrium phase diagrams. It is found that the atomic size difference is the single most important factor in the quantitative determination of the composition range

Mössbauer study of sputtered Fe-Ti alloys with wide composition range

FexTi100-x alloys over a wide composition range has been made by high-rate sputtering and studied by 57Fe Mössbauer spectroscopy. Samples with 30 ≤ x ≤ 80 are amorphous whereas samples with x ≥ 85 are metastable crystalline bcc alloys. Large differences in magnetic properties (e.g., Tc) and hyperfine interactions (Heff, isomer shift) are found between the amorphous and bcc alloys. Comparison of FeTi and Fe2Ti in amorphous and crystalline states show that the short-range order in the amorphous state has no resemblence to that of the crystalline compounds

Composition range of binary amorphous alloys

We have studied a number of binary metal-metal and metalloid alloy systems made by a single vapor-quench method under very consistent conditions. In each case, amorphous alloys are found in one continuous composition range (xmin≤x≤xmax) regardless of the number of eutectic points in the equilibrium phase diagrams. It is found that the atomic size difference is the single most important factor in the quantitative determination of the composition range

Recent Developments in Majority-Logic Decoding

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / DAAB-07-67-C-0199Rome Air Development Center / F 30602-70-C-001

Application of feedback linearization to tracking and almost disturbance decoupling control of the AMIRA ball and beam system

This paper studies the tracking and almost disturbance decoupling problem of the nonlinear AMIRA ball and beam system based on the feedback linearization approach. The main contribution of this study is to construct a controller, under appropriate conditions, such that the resulting closed-loop system is valid for any initial condition and bounded tracking signal with the following characteristics: input-to-state stability with respect to disturbance inputs and almost disturbance decoupling. Two examples on the almost disturbance decoupling problem, which cannot be solved via Ref. 1, are proposed in this paper exploiting the fact that the tracking and the almost disturbance decoupling performances are easily achieved by our proposed approach

An Error-Control System Based on Majority-Logic Decoding

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / DAAB07-72-C-0259Rome Air Development Center / F30602-72-C-003

Negative Hall coefficient of ultrathin niobium in Si/Nb/Si trilayers

International audienceStructural and transport properties of thin Nb layers in Si/Nb/Si trilayers with Nb layer thickness d from 1.1 nm to 50 nm have been studied. With decreasing thickness, the structure of the Nb layer changes from polycrystalline to amorphous at d 3.3 nm, while the superconducting temperature T c monotonically decreases. The Hall coefficient varies with d systematically but changes sign into negative in ultrathin films with d < 1.6 nm. The influence of boundary scattering on the relaxation rate of carriers, and band broadening in the amorphous films, may contribute to this effect

Experimental Unit for (31,16) Binary Code Using Majority-Logic Decoding

Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / DAAB-07-72-C-0259Rome Air Development Center / F30602-72-C-003

The contents and forms of solid-phase species of radioactive strontium and cesium in Taiwan soils

This study was to investigate the activities and contents of Cs-137 in the profiles of selected arable and forest soils in Taiwan and various solid-phase species of Sr-85 and Cs-137 in selected arable soils in Taiwan. The gamma (gamma) ray spectra of the collected soil samples and some of the soils amended with Sr-85 and Cs-137 were measured. The data indicate that the arable soils from Sanhsing series, Sanhsing Township and Chuangwei series, Chuangwei Township, Ilan County, and from Tunglochuan series, Pinglin Township, Taipei County shows significantly higher radioactivity of Cs-137 ( ND - 11.0 +/- 0.2 Bq kg(-1)). Furthermore, the radioactivity of Cs-137 in the mountain soils ( 1.24 +/- 0.07 - 42 +/- 1 Bq kg(-1)) from Yuanyang Lake Nature Preserve among Ilan, Taoyuan, and Hsinchu Counties is the highest among the investigated mountain forest soils. This may be mainly attributed to the fact that Ilan County is located in the northeastern part of Taiwan and faces the northeastern and northern seasonal winds with lots of precipitation annually from mid-autumn through mid-spring next year and is receiving greater amount of fallouts yearly. Due to longer reaction period (> 3 y) of Cs-137 with soil components, Cs-137 was mainly in the forms bound to oxides and to organic matter in the soil amended with Cs-137 and in the soil contaminated with Cs-137. On the contrary, due to shorter reaction period (< 60 d) of Sr-85 with soil components, Sr-85 was mainly in exchangeable form and partially in the forms bound to carbonates and oxides in the soils amended with Sr-85

Expression, crystallization and preliminary X-ray diffraction studies of N-carbamyl-D-amino-acid amidohydrolase from Agrobacterium radiobacter

The Agrobacterium radiobacter CCRC 14924 N-carbamyl-D-amino-acid amidohydrolase, the enzyme used for production of D-amino acids, was overexpressed in Escherichia coli JM109. The expressed protein was crystallized by vapour diffusion using lithium sulfate as precipitant. It crystallizes in space group P2(1) with unit-cell parameters cr = 69.8, b = 67.9 and c = 137.8 Angstrom and beta = 96.4 degrees. There are four molecules per asymmetric unit. Crystals diffract to 2.8 Angstrom resolution using a rotating-anode source at cryogenic (113 K) temperatures