An Electronic Approach to Materials Design

A molecular orbital approach to materials design has recently made great progress. This approach is based on the electronic structure calculations by the DV-Xα cluster method. In this paper recent progress in this approachis reviewed. In particular     

APPLICATION OF d-ELECTRON ALLOY DESIGN THEORY TO DEVELOPMENT OF HOT CORROSION RESISTANT Ni-BASE SINGLE CRYSTAL SUPERALLOYS——Ⅰ Characterization of Phase Stability

为应用d-电子合金设计理论(或新相分计算法(New PHACOMP))设计发展新型抗热腐蚀单晶高温合金,首先对高Cr抗热腐蚀IN738LC系列合金Ni—16Cr—9.5Al—4.0Ti-8.0Co—0.55Nb—0.06Zr—0.05B—0.47C-Ta—W—Mo(at-％)的相稳定性进行了综合评价得出抑制σ相析出的稳定性临界条件为Mdt<0.991或Mdγ<0.93同时证明这两个临界电子参数具有等价性,可以用Mdt代替Mdγ简化合金设计过程.这一结果可适用于其它高Cr系列抗热腐蚀镍基合金的d-电子合金设计     

Day‐Ahead Global Solar Radiation Forecasting Using Binary Trees and Factor Analysis

A method is proposed for forecasting global solar radiation. The method is based on weather information using binary trees and factor analysis. The feature of this method is that it is possible to use a simple linear forecasting equation. The method has been tested on meteorological and global solar radiation data obtained at several observation sites, and the results show that it is a promising means of maintaining the balance between demand and supply of electric power in power systems of the near future with a large number of photovoltaic systems installed.     

An application of Markov potential theory to Markovian decision processes

The aim of this paper is to identify the denumerable stochastic systems which have an optimal strategy, namely, to give general sufficient conditions of the existence of an optimal strategy for denumerable Markovian decision processes. The aim is accomplished by using Markov potential theory and showing the range of the validity of a method to find an optimal strategy called Howard's technique. Since Markov potential theory helps to characterize the properties of evaluations of strategies on such processes, it plays an important role to find the sufficient conditions mentioned above

For Markov potential theory, new concepts are introduced such as absorbable chains, quasi-potentials, etc., and using them, sufficient conditions for the existence of a solution of the equation x = f+Px are generalized to the one's for cyclic chains and multi-chains

The results obtained in this paper are as follows : if a system represents a strong Markov chain for any strategy, then there exists an optimal strategy with respect to the total or the mean expected earnings, and for any stochastic system there exists an optimal strategy with respect to the discounted total expected earnings.     

Far Infrared Reflection Spectra of Ba(Zn,Ta)O3-BaZrO3 Dielectric Resonator Material

The dielectric ceramic materiala Ba(Zn_1/3Ta_2/3)O₃–BaZrO₃ has extremely low dielectric loss at microwave frequencies. To investigate the lattice vibrations of Ba(Zn,Ta)O₃ and Ba(Zr, Zn, Ta)O₃ solid solutions, far infrared reflection spectra were measured from 50 to 4000 cm⁻¹ using a Fourier transform infrared spectrometer. These data were analyzed according to the classical dispersion theory. The spectra of Ba(Zn,Ta)O₃ are well fitted by using the 14 resonant modes, and the spectra of Ba(Zr, Zn, Ta)O₃ solid solution are fitted by assuming the normal distribution on resonant frequencies. The damping constant of these materials is discussed, and the values of tan δ calculated from the dispersion parameters agree with the measured values.     

Preparation and Thermal Properties of Dense Polycrystalline Oxyhydroxyapatite

Solution-grown crystals of hydroxyapatite were sintered into polycrystalline oxyhydroxyapatite bodies, using the range 1050 to 1450°C. The heat capacity, thermal diffusivity, and thermal conductivity of the sintered bodies were measured by the laser flash method at 130–1000 K. The sintered bodies were 94.4 to 99.4% of theoretical density and 0.8 to 12 μm in grain size. Sintering is accompanied by grain growth and by vacancy formation and cell contraction due to thermal dehydration. Typical values of the heat capacity, thermal diffusivity, and thermal conductivity at room temperature are 0.73 J/g K, 0.0057 cm²/s and 0.013 J/s cm K, respectively. Low-temperature thermal conductivity increased with increasing temperature, similarly to that of amorphous solids. This odd behavior is discussed in terms of phonon mean free path.     

LIPID CLASSES, FATTY ACID COMPOSITIONS AND TRIACYLGLYCEROL MOLECULAR SPECIES FROM ADZUKI BEANS (VIGNA ANGULARIS)

The lipids extracted from adzuki beans grown in Japan were classified by thin-layer chromatography (TLC) into eight fractions. Molecular species and fatty acid distributions of triacylglycerols (TAGs) isolated from the total lipids in the beans were determined from a combination of argentation-TLC and gas chromatography. The major lipid components were phospholipids (PL; 63.5%) and TAG (21.2%), while hydrocarbons (5.1%), steryl esters (7.5%), free fatty acids (0.9%), diacylglycerols (1.3%) and monoacylglycerols (0.5%) were also present in minor proportions. Both major samples had high amounts of total unsaturated fatty acids, representing 62.1% for TAG and 65.9% for PL. Seventeen different molecular species were detected. The major TAG components were SMD (5.0%), S₂T (19.3%), SD₂ (13.8%), SMT (9.3%), MD₂ (4.5%), SDT (7.0%), D₃ (8.8%) and ST₂ (15.9%), where S, M, D and T denote a saturated fatty acid, a monoene, a diene and a triene, respectively.

PRACTICAL APPLICATIONS

This article describes the characteristics of lipid components, fatty acid compositions as well as the profiles of triacylglycerol (TAG) molecular species of adzuki beans. α-Linolenic (18:3 n -3) acid was detected as 24.8, 21.2 and 15.2% in the TAG, total lipids and phospholipids, respectively. The oil from legumes, except the profitable fatty acid content, could be a potential source of tocopherols. The data obtained in this study would be useful to both consumers and producers for manufacturing traditional adzuki confectionaries ( wagashi ) in Japan and elsewhere.     

Microstructures of SrTiO3 Internal Boundary Layer Capacitors During and After Processing and Resultant Electrical Properties

The microstructure of strontium titanate internal boundary layer capacitors at various stages in their processing was studied by transmission electron microscopy of rapidly quenched and normally cooled samples. Compositions containing excess TiO₂, Al₂O₃, and SiO₂ have a completely wetting liquid phase at the sintering temperature; during cooling Ti_nO_{2 n −1}, Magneli phases precipitate at multiple grain junctions. Diffused metal oxides and flux (Bi₂O₃, PbO, CuO, and B₂O₃) rapidly penetrate as a liquid phase along boundaries in postsintering heat treatment. This liquid phase disappears during slow cooling.     

高Cr含量镍基高温合金热腐蚀行为研究──I．实验研究

系统研究了合金元素Ｔｉ，Ｔａ和Ｎｂ对合金系统Ｎｉ－１６Ｃｒ－９Ａｌ－２Ｗ－１Ｍｏ－４Ｃｏ－（０～４）Ｔｉ－（０～４）Ｔａ－（０～４）Ｎｂ（ａｔ％）热腐蚀行为的影响。结果表明在一定的成分范围内，实验合金在７５Ｎａ２ＳＯ４＋２５ＮａＣｌ（体积分数）溶盐中的热腐蚀抗力类似于ＩＮ７３８ＬＣ合金。在较高的热腐蚀抗力条件下，合金系列保持了较好的其它性能，这就为开发高性能抗热腐蚀单晶高温合金提供了成分选择的基础。     

Learning automaton as a model to simulate and analyse learning behaviour in rats

A technique is presented for using a learning automaton as a model to simulate and analyse learning behaviour in rats, and the usefulness of this model is illustrated. This automaton was proposed as a learning machine by Tsetlin (1961) and refined by Aso and Kimura (1976). Some learning properties of such an automaton are first examined and it is shown that the automaton can be used to simulate a variety of learning behaviour, composed of several kinds of action, by the proper selection of parameters. Secondly, a mathematical model of the learning experiment carried out in our laboratory with rats is formulated as an interactive system between a learning automaton and its environment. Finally, the effectiveness of the mathematical model is discussed and proved through the simulation and analysis of learning behaviour with multiple actions in a specific rat.