Showing papers by "Utsunomiya University published in 1991"

Electronic structure of the misfit-layer compounds PbTiS3 and SnNbS3.

Abstract: The compounds ${\mathrm{PbTiS}}_{3}$ and ${\mathrm{SnNbS}}_{3}$ may be classified as misfit-layer compounds with compositions (PbS${)}_{1+\mathit{x}}$${\mathrm{TiS}}_{2}$ or (SnS${)}_{1+\mathit{x}}$${\mathrm{NbS}}_{2}$. Their structure is such that a double layer of PbS or SnS with the TlI structure is inserted into each van der Waals gap of a layered transition-metal disulfide. They may be regarded as intercalation compounds or as materials having a one-dimensional superlattice with an atomic-scale repeat distance. X-ray-photoemission-spectroscopy, x-ray-absorption-spectroscopy, and reflection-electron-energy-loss-spectroscopy spectra are presented and the electronic structures are discussed. It is found that charge transfer occurs from the PbS or SnS layers to the transition-metal disulfide slabs, but the interlayer interaction is so small that the overall features of the valence and conduction bands of each layer are considered to be almost unchanged from those of the bulk compound.

Physicochemical Properties of Milk Fat Emulsions Stabilized with Bovine Milk Fat Globule Membrane

Abstract: Milk fat globules (MFG) were reconstituted with milk fat globule membrane (MFGM) and milk fat (MF). Viscosity of the reconstituted MFG was highest at pH 5.0 and 4 min emulsifying, and rose with an increase of MFGM between 40–80 mg/g fat. Adsorbed protein/unit fat increased at acid pH with increase of MFGM. The composition of proteins adsorbed on the surface of MFG was not influenced by factors of reconstitution. The size and specific surface area of globules were influenced by emulsifying time, MFGM and MF concentrations, and pH. The size range of MFG prepared by standard method was 0.9–17 μm in diameter. Median diameter was 5 μm and specific surface area was 15,600 cm2/cm3 of emulsion.

Chaos via torus breakdown in a piecewise-linear forced van der Pol oscillator with a diode

Abstract: Chaos via torus breakdown in the piecewise-linear forced van de Pol equation is studied rigorously by using the degenerate technique. The model is a negative resistance LC oscillator including a diode driven by a sinusoidal voltage source. The authors investigate an idealized case where the diode is assumed to operate as an ideal switch. In this case, the Poincare map is derived strictly as a one-dimensional return mapping of a circuit onto itself. This mapping clarifies the onset of chaos via torus breakdown observed in this circuit. The authors obtain the critical value of the bifurcation parameter analytically, which gives the boundary between the chaotic region and the torus region. This bridges the gaps between the abstract one-dimensional mapping and the real circuit. >

Critical Discussion on Abortive Interspecific Crosses in Brassica

Abstract: In most interspecific hybridization among diploid Brassica species (n = 8, 9, 10), few or no hybrids are obtained, and the three crosses of tetraploid (n = 17, 18, 19) by diploid species are usually only partially successful, especially in one of the reciprocal crosses. Such a cross-incompatibility complex is explained in this paper by a polar-nuclei activation (PNA) hypothesis which proposes two reversible functions, a normal reproduction and a sexual barrier, of double fertilization in higher plants. The first, i.e. the relative activating value (AV) of diploid species, was estimated as 1.0–3.5, whereas that of tetraploid species was 2.7–5.2. In addition, crosses with a polar nuclei activation index (AI) of about 15–87 % were compatible but those beyond the two limits were incompatible, 50 % of those showing normal seed development after self-pollination.

A Significant Method for Estimation of the Grain Size of Polycrystalline Materials

Abstract: A method has been proposed to estimate the grain size, which is defined as the grain size distribution in three dimensions, from the measured distribution of linear intercept length. The method is developed on the assumption that the grain size distribution is log normal in three dimensions. The three-dimensional grain size distribution is expressed as that of the «grain diameter» D defined as the equivalent volume diameter; the distribution of D is estimated from In D g and In σ g , (where D g is the geometric mean of D and σ g is the geometric standard deviation for D)

Bifurcation sets and chaotic states of a gear system subjected to harmonic excitation

Abstract: The gear dynamics is described by a time-varying nonlinear differential equation due to the time dependence of tooth stiffness and backlash. To discuss whether or not distinctive new phenomena occur in the gear system with its backlash and time-variable characters is an important and interesting problem from a practival viewpoint of estimating the dynamic load or gear noise as well as an academic one of contribution to nonlinear mechanics. In this study, the bifurcation sets of periodic solutions under some gear parameters are obtained and chaotically transitional phenomena are investigated by using the Poincare map.

Binding form of vitamin b2 in bovine milk : its concentration, distribution and binding linkage

Abstract: The contents of total, free, and bound vitamin B2 (B2) in bovine milk and their distribution in four separate milk fractions, including milk during the early lactation stage, were estimated. The total B2 content in whole mature milk was 179±25μg/100g (n=16), and its distribution in the cream, whey, skim milk membrane, and casein fractions was 6, 67, 9, and 18%, respectively. The amount of flavins bound to protein in the total B2 was 13.6% in whole milk and rich in membrane fraction. The total B2 content (μg/100g of milk) was higher in colostrum at 1-3 days (287±120) than in colostrum at 4-7 days (173±27), in transitional milk (182±33), and in mature milk (179±44). The bound flavin content decreased slightly as lactation progressed (20-30μg/100g), but the ratio of bound/total B2 did not vary (12-15%). Milk fat globule membrane (MFGM) contained 414±65μg of B2/g of protein, most of it being bound to protein (92%). Market milks contained as much total B2 as raw whole milk, but the amount of bound form was only 2%. Guanidine HCl, urea, sodium dodecyl sulfate, pH at 3.0-3.5, delipidation, and boiling released most of the B2 bound to protein, suggesting that bound flavins bind to milk proteins by a hydrophobic linkage.

Self-avoiding process on the Sierpinski gasket

Abstract: We construct a self-avoiding process taking values in the finite Sierpinski gasket, and study its properties. We then study “continuum limit” processes that are suggested by the statistical mechanics of self-avoiding paths on the pre-Sierpinski gasket. We prove that there are three types of continuum limit processes according to the parameters defining the statistical mechanics of self-avoiding paths: (i) the self-avoiding process we construct in this paper; (ii) a deterministic motion along a “Peano curve” on the finite Sierpinski gasket; (iii) a deterministic motion along a line segment.

Excitation of large-amplitude ion-wave wake fields.

Abstract: Plasma wake fields in the ion-wave regime have been excited by injecting ion bunches with a variety of shapes. An excited-wave amplitude (\ensuremath{\delta}n/${\mathit{n}}_{0}$) of up to 17% has been observed for a bunch falloff time less than the wake-field period. The large-amplitude wake wave damps out, along with oscillations of the wave envelope. A simple linear theoretical model is developed, which can explain most of the observed phenomena, except for the large-amplitude oscillations.

Simple Method for Separate Determination of Three Flavins in Bovine Milk by High Performance Liquid Chromatography

Abstract: Milk, dialyzed milk and milk fat globule membrane (MFGM) (1.0g each) were boiled 3 min to inactivate pyrophosphatase. Release of flavins bound to milk proteins and deproteinization were performed simultaneously by Pronase digestion for 1 hr at 45°C. After centrifugation, the extracted flavins were analyzed by HPLC, using a C18 column at 40°C connected to a spectrofluorometer. Recovery of FAD, FMN and riboflavin was 97–99% from whole milk, 95–100% from dialyzed milk, and 99-100% from MFGM. The method is simple, rapid, sensitive and reproducible. Bovine milk contained 202 μg of total flavins per 100g milk, of which FAD was 13.8, FMN 4.3, and RF 81.9mol%(n=6).

Effect of Root Temperature on the Flower Formation and Fruit Yield of Tomatoes

Abstract: In this study, the effects of root temperatures on flower formation and fruit yield of tomato plants were investigated.1. Roots of young tomato seedlings were bathed in containers of nutrient solution kept at temperatures ranging from 10°to 35°C at 5°C intervals. The experiments ran from 14 to 21 days beginning at cotyledon expansion. Shoot and root growths of seedlings kept at root temperatures 25°and 30°C were greater than those of seedlings grown at other root temperatures. The number of flowers on the first truss of plants whose roots were exposed to 25°C was greater than those on trusses of seedlings grown at other root temperatures, whether the air temperature remained constant at 20°or fluctuated between 20°and 30°C. No difference in the number of nodes on the primary axes among plants was found in this experiment.2. In experiments conducted during three different times of the year; spring, late spring to early summer, and late fall to early winter, roots of plants were exposed to various temperatures from anthesis of flowers on the first truss to fruit harvest on the third truss. Shoot growth of plants grown at root temperatures between 20°and 30°C was better than that of plants grown at other root temperatures. Root temperatures favorable for root growth have a range lower than that for optimum shoot growth. Fruit production from plants grown at root temperatures of 10°and 35°C was very low because of poor fruit set and growth, especially on those of second and third trusses.3. Fruit ripening was accelerated on plants grown at root temperature of 10°and 15°C, especially in the 15°C treatment if the nutrient solution was low in nitrogen.4. These results confirm that the optimum range of root temperatures for the growth of tomato vines widens with increasing size and age of plants from the young seedling stage to mature producing vines, that is 25°30°C during the flower differentiation period in the first truss, 20°30°C for the vegetative growth stage, and 15°30°C during fruit production.

The viable 3.5n trouts produced between diploid females and allotriploid males.

Abstract: Eyed embryos and fingerlings of trouts between diploid females and allotriploid males were obtained. There were two groups, namely, one group with the chromosome number of 79-83 (group I), and another with that of 110-112 (group II). Judging from numbers and constitutions of the chromosomes, it is presumed that the individuals in group I were 2.5n and those in group II were 3.5n. All fingerlings were 3.5n, and 2 fingerlings of them were still surviving as of September, 1990, about 7 months after the hatching.

Kα X-Ray Emission Spectra and K X-Ray Absorption-Edge Structures of Fluorine in 3d Transition-Metal Difluorides

Abstract: The fluorine K α emission spectra in fluorescence from a series of 3 d transition-metal difluorides MF 2 (M=Mn, Fe, Co, Ni, Cu and Zn) have been measured with a high-resolution two-crystal vacuum spectrometer. It is shown that the observed FWHM of the K α 1,2 emission band is closely related to the difference in the electronegativity between the metal and fluorine atoms. The measured emission spectra are presented along with the UPS or XPS spectra of the valence bands and the fluorine K absorption spectra of the metal difluorides, reported previously. The structures at the fluorine K absorption edges are interpreted in terms of a molecular orbital (MO) model.

Phase stability of al3nb as a function of nickel additions

Abstract: Phase stability of the intermetallic compound Al3Nb is investigated as a function of nickel additions by band structure calculations based on an extended Hueckel tight-binding method. With this method, the electronic structure and total energies of the Al6-n -Ni n Nb2 compounds (where n is an integer from 0 to 6) are calculated for both D022 and L12 structures under the assumption that nickel substitutes for aluminium. The electronic total energies obtained from integration of the energy states of all electrons considered have shown that the D022 structure is stable in the binary Al3Nb compound as compared with the L12 structure; conversely, the L12 structure is stable for compounds with n values greater than 1. These calculations are in good agreement with X-ray diffraction results reported by Schubert and co-workers. Differences in the electronic total energy per atom between D022 and L12 are - 0·79 eV and 0·56 eV for n equal to 0 and 2, respectively.

Fluorine-Kα and Chlorine-Kβ Emission Spectra from Alkali Fluorides and Chlorides

Abstract: The fluorine- K α and chlorine- K β emission spectra in fluorescence from a series of alkali halides MX (M=Li, Na, K, Rb and Cs; X=F and Cl) are measured with a high-resolution two-crystal spectrometer. Solid-state effects are observed on the intensities of the K 1 L 1 and K β x satellite peaks in the K α and K β emission spectra, respectively. An anomalously low intensity of the K 1 L 1 satellite peak is observed for KF. The measured emission spectra are presented along with the UPS spectra of the F - 2 p and Cl - 3 p valence bands obtained by Poole et al ., the fluorine K absorption-edge spectra by Nakai et al . and the chlorine K absorption-edge spectra by the author. By using these spectra, the first shoulder at the K absorption edge is identified as being due to a core exciton, the energy level of which is formed below the bottom of the conduction band. The binding energy of the exciton is estimated.

Enzymic modification of αs1-casein with peptidylarginine deiminase : preparation of less acid-coagulable and less calcium-sensitive casein

Abstract: Enzymic modification with peptidylarginine deiminase (EC 3.5.3.15) enabled five out of six arginyl residues in alpha s1-casein to be converted to citrullyl residues, only the N-terminal arginyl residue remaining unaffected. An increase in the net negative charge was confirmed by PAGE. The isoelectric point was decreased from 4.46 for the intact alpha s1-casein to 4.30 for the deiminated type, while simultaneously lowering the acid-precipitation starting point from pH 5.17 to pH 4.62. The deiminated alpha s1-casein self-associated less in the absence of Ca and was less Ca-sensitive than the native type, although its Ca-binding ability was slightly enhanced. In the presence of 25 mM-CaCl2 and kappa-casein, Ca-induced precipitation of alpha s1-casein did not occur, the solution of the mixture remaining transparent. Deimination of alpha s1-casein resulted in altering its characteristics, possibly by interfering with interactions through hydrophobicity and/or hydrogen bonding. The positive charge of the arginyl residues might play an important role in casein micelle formation.

Gibberellins from the Seed, Tassel, Cob and Silk of Maize

Abstract: Endogenous GAs in the immature seed of maize (hybrid Ko-No. 7) were analyzed, and GAl, GA4, GA8, GA9, GA17, GA19, GA20, GA29, GA34, GA44 and GA53 were identified by GC/MS and/or GC/SIM. Among these GAs, GA20 was the major one.Endogenous GA1, GA3 and GA4 in the tassel, cob and silk of maize were analyzed, and gave information that suggests a role for GAs in the reproductive organs of maize.

Herbicidally Active N-(1-Arylethenyl)-2-chloroacetamides Bearing an Alkyloxyalkyl Moiety

Abstract: N-(1-Arylethenyl)-2-chloroacetamides were synthesized and their herbicidal activities were tested. Among them, both 2-chloro-N-(2-methoxyethyl)-N-(2-methyl-1-phenylpropen-1-yl)acetamide and 2-chloro-N(2-ethoxyethyl)-N-(2-methyl-1-phenylpropen-1-yl)acetamide were found to be highly active against upland weeds.

Access methods of a two‐dimensional access memory by two‐dimensional inverse omega network

Abstract: This paper discusses an organization of a parallel memory, in which any local area of a two-dimensional (2-D) array can be accessed. The proposed memory system is composed of a memory array, which is a 2-D array composed of memory modules and a 2-D interconnection network with a 2-D array of input/output terminals. It is used with a 2-D processor array for local parallel processing, realizing a parallel access to sub-arrays of the 2-D array stored in the memory array. This paper describes a method to store the 2-D array in the memory system, a method of address generation for the memory array to perform parallel access, and a control method for the interconnection network. It is shown that those ideas can be realized by a simple hardware, and the proposed memory system is useful in the computer executing the local parallel processing of 2-D arrays.

The Surface-treatment of Ceramic Powders through Pulverization in a Reactive Atmosphere by Means of Ball Mill (IV)

Abstract: The surface properties of silicon carbides pulverized in n-hexane and n-hexane solutions of cetanol or octadecyltriethoxysilane were investigated through their dispersive properties, by scanning electron micrographs (SEM), infrared absorption spectra, pyrolysis and the number of surface groups estimated from carbon contents and surface areas. The following were confirmed: (1) The surface nature of silicon carbide pulverized in n-hexane was hydrophilic and was similar to that of unpulverized silicon carbide. The surface nature of silicon carbide pulverized in an n-hexane solution of cetanol appeared to be hydrophilic, but it was hydrophobic in comparison with that of unpulverized silicon carbide. The surface nature of silicon carbide pulverized in an n-hexane solution of octadecyltriethoxysilane appeared to be hydrophobic (2) The pulverization was confirmed by SEM to proceed with increase in grinding time. (3) The characteristic absorption due to surface groups was observed in that of silicon carbide pulverized in n-hexane solutions of cetanol or octadecyltriethoxysilane. The vapors evolved by the pyrolysis of the surface group were observed. (4) The surface-treatment of silicon carbide was confirmed to be performed by pulverization in n-hexane solutions of cetanol or octadecyl-triethoxysilane. (5) The reaction mechanisms were confirmed to be,