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Chitosan films with or without chemicals of interest were prepared and degradation properties of chitosan films of themselves by lysozyme and releases of the loaded chemicals from the films were investigated. Enzymatic degradation rate of the films was dependent on the degree of deacetylation of chitosan used and decreased with an increase in its deacetylation. The acidic conditions accelerated the degradation compared to the neutral pH. Most of the water-soluble chemicals used in the present experiments except Coomassie Brilliant Blue with a strong acidic group and pullulan with a high molecular weight (5.8 x 10(4)-38.0 x 10(4], were rapidly released from the films within 1 h. The two chemicals described above were released only in the presence of lysozyme, and their release rates were controlled by the degradation rate of the films.

Seven kinds of hypervariable DNA probes, which recognize hypervariable loci, were applied for individual identification of human bloodstains. Allelic frequencies and their confidence intervals among unrelated Japanese individuals were previously reported from our laboratory, and codominant segregation of the polymorphism was confirmed in family studies. One-month-old bloodstains from ten individuals were investigated in the present study. The probability of matching was calculated using the database among Japanese population. Cumulative probability of matching from 7 kinds of hypervariable DNA probes was 1.1 x 10(-11), which was 4.5 x 10(9) times higher than that from 6 kinds of common blood group markers such as ABO, MN, Rh-Hr, P1, Hp and PGM1. Accordingly, DNA polymorphism is considered to be informative enough for individual identification of bloodstains.

Bi0.5Na0.5TiO3 (BNT) bulk ceramics with a preferred orientation (texture) were prepared by the reactive-templated grain growth method using platelike Bi4Ti3O12 (BiT) particles as templates for BNT. The texture did not develop extensively in stoichiometric BNT, but the addition of excess Bi2O3 to BNT enhanced the texture development. The role of excess Bi2O3 was examined. The calcined compacts were composed of matrix grains with random orientation and -oriented grains transformed from aligned BiT particles, and texture developed by the preferential growth of oriented grains at the expense of matrix grains. In stoichiometric BNT, the growth rate of matrix grains was high and the conditions for the preferential growth of the oriented grains were disrupted. Excess Bi2O3 reduced grain growth rate, and the conditions for preferential growth were maintained, resulting in the development of highly textured BNT. The resultant textured BNT ceramic exhibited 70% higher piezoelectric d 31 and electromechanical k p coefficients than nontextured BNT.

Barium magnesium aluminate. BaMgAl 10 O 17 , was synthesized by a solid-state reaction between Al 2 O 3 and sol-gel-derived BaMgF 4 precursors. The reaction temperature necessary for producing a single-phase material was reduced to 1300°C because of the higher reactivity and lower melting point of the fluoride precursors. Eu-doped BaMgF 4 was also prepared and characterized to examine its suitability as a precursor for synthesizing BaMgAl 10 O 17 :Eu 2+ blue phosphors. It was demonstrated that Eu 3+ , which was used in the acetate form as a starting material, was reduced to Eu 2+ in the sol-gel processing of BaMgF 4 , as indicated by a broad blue emission due to an allowed d-f transition at 420 nm with an ultraviolet excitation at 290 nm. BaMgAl 10 O 17 :Eu 2+ , which showed efficient blue emissions at 450 nm with an ultraviolet excitation at 254 nm, was successfully prepared by heating a mixture of Al 2 O 3 and Eu-doped BaMgF 4 at 1300°C without any special reducing treatment.

Nanocrystalline ZnO phosphor films were prepared from an ethanolic solution of zinc acetate dihydrate on fluorine-doped tin oxide coated glass substrates through a chemical bath deposition at a low temperature of 60°C. Because the deposition was achieved without using a base such as NaOH or LiOH, the ZnO film prepared was chemically pure in terms of cation impurities. It was indicated that the deposition of ZnO proceeded through the formation and conversion of intermediate compounds such as layered hydroxide zinc acetate, Zn 5 (OH) 8 (CH 3 COO) 2 .2H 3 O. Green photoluminescence from the film was observed by ultraviolet excitation.

Micro/nanoporous ZnO ∶ Al films were fabricated through the pyrolytic transformation of AlCl3-added layered hydroxide zinc acetate (LHZA) self-templates. Formation of the self-templates on glass substrates was achieved on the basis of heterogeneous nucleation and crystal growth that proceeded in a chemical bath composed of zinc acetate dihydrate, aluminium chloride hexahydrate, and methanol, kept at a small degree of supersaturation. The LHZA self-templates had a nest-like morphology with interlaced sheet-like particles. Pyrolysis of the template films at low temperatures resulted in the formation of ZnO without microstructural deformation. The electrical resistance of the ZnO films exhibited minimum values when aluminium was added to the chemical bath at concentrations around 0.5 at.%. These results suggest that we achieved successful Al-doping of micro/nanoporous ZnO films.

Alumina powder was consolidated by slipcasting of suspensions with pH between 2 and 9, and then fired under various time-temperature conditions. The effects of agglomerates on the pore structure in green compacts and on the microstructure development during sintering were studied. An increase in the pH value of the suspension from 2 to 9 increased the agglomerate size in the suspension, resulting in an increase in both pore size and pore volume in green compacts. The sintering behavior was studied for the compacts made from the suspensions of pH = 2 and 9. The pH = 2 compact densified faster than the pH = 9 compact, without any significant difference in the microstructure development, which was characterized by the formation of well-sintered regions during the early stage of sintering (density

The mechanism of the color reaction and the structures of the colored products of cortisone (1a) and deoxycorticosterone (2a) with pyrrole were elucidated. In the presence of cupric acetate, la and 2a were converted to the oxidation products (1b and 2b) which have a glyoxal side chain at C (17). For studying the chemical structures of the colored products derived from corticoids, phenylglyoxal (3a) was used as a model compound with a glyoxal side chain. By reacting 3a with pyrrole in hydrochloric acid, di (2-pyrrolyl) benzoylmethane (3b) was produced as an intermediate in the formation of the colored product. Compound 3b was changed to [5- (2-pyrrolyl) -2 (2H) - pyrrolylidene] (2-pyrrolyl) benzoylmethane (3d) by reaction with pyrrole in the presence of cupric acetate and hydrochloric acid. Compound 3d in dichloromethane gave the absorption maximum at 480 nm. Corticoids 1b and 2b were converted to the colored products, 21- [5- (2-pyrrolyl) -2 (2H) - pyrrolylidene] -21- (2-pyrrolyl) -4-pregnene-3, 11, 20-trione (1e) and 21- [5- (2-pyrrolyl) -2 (2H) -pyrrolylidene] -21- (2-pyrrolyl) -4-pregnene-3, 20-dione (2e), by reaction with pyrrole under the above conditions. Corticoids 1e and 2e in dichloromethane gave absorption maxima at 510 and 480 nm, respectively. Corticoid 1e showed fluorescence at 562 nm with excitation at 516 nm.

Grain-oriented Bi4Ti3O12 ceramics have been prepared by hot-pressing. Platelike grains align during hot-pressing; the long-axis direction perpendicular to the crystal c axis is oriented perpendicular to the pressing direction. The effects of hotpressing conditions such as temperature, pressure, time, and type of filler on the density, orientation degree, and deformation of hot-pressed compacts were examined. Sharp increases in the density, deformation, and grain orientation occurred during the early stage; the density decreased, and the latter two incresed on prolonged hot-pressing. The grain orientation is closely related to the deformation in the radial direction. The grain-orientation mechanism is discussed referring to mechanisms proposed for high-temperature deformation in ceramics. The compact is deformed by two processes: one accompaines grain orientation, and the other does not. Grain-boundary sliding is proposed for the former process. The contribution of grain-boundary sliding to the deformation increases with increasing temperature and pressure. The filler also influences the contribution. The decrease in density is caused by cavity formation during prolonged hot-pressing.

The effects of grain size on the isothermal cation ordering in sintered Mg‐ferrites have been studied from 400 to 750 °C by thermomagnetic analysis. The observed dependence of ordering behavior on the grain size as well as on the temperature has proposed that the rate‐determining process changes from nucleation growth to homogeneous ordering as the temperature increases. The high rates of ordering in fine‐grained specimens have been interpreted as due to the increased grain‐boundary areas favorable for nucleation. The apparent activation energy of the homogeneous ordering is 36 kcal/mole in the temperature range between 450 and 600 °C.

In order to investigate the functional role of the region around the A and B rings of 20-oxo-steroids in the interaction with the binding site of 20β-hydroxysteroid dehydrogenase, kinetic studies were made using 28 kinds of steroids which differed in the nature of the substituent, and in the shape and electronic character of the region around the A and B rings. Structural changes in the A ring of steroids, such as reduction of pregn-4-ene derivatives to the corresponding 5α- or 5β-pregnane derivatives, introduction of a further double bond into the A ring, and change of the 5α-series to 5β-series or change in the configuration and size of the substituent at C-3 caused only small changes in the apparent Km and Vmax values. It is suggested that the region around the A ring is of little significance in the interactions between a steroid molecule and the enzyme. It seems unlikely that the electronic character and shape of the B ring affect the steroid-enzyme interaction, since introduction of a C-5/C-6 double bond scarcely changed the kinetic constants. Neither a nonpolar (methyl group) nor a polar (hydroxyl group) substituent at the C-6 α-position (equatorial) produced any appreciable changes in the kinetic constants. Further, a 6-methyl group and a 9α-fluoro group (axial) did not cause any marked changes in the kinetic constants. On the other hand, introduction of a hydroxyl group at the C-6 β-position (axial) or removal of the 10β-methyl group caused a marked increase in the apparent Km. These findings suggest that recognition of the steroid moiety by the enzyme may involve the 10β-methyl group and the region around the β-side of the B ring. The nature of the interaction of these regions of the steroid with the enzyme may be hydrophobic, since a polar 6β-hydroxyl group had a marked repulsive effect on the steroid binding site of the enzyme, while a 10β-methyl group increased the binding affinity of the steroid.

Paleozoic and Mesozoic geosynclinal strata in Japan have long been thought to be very thick and to form high angled homocline. Recent studies by KIMURA and others, however, show that those strata form small scale isoclinal folds with gently folded enveloping surfaces in a large scale, and that the strata are rather thin, less than several thousand meters.On the other hand, Upper Triassic conodonts have recently been found by IGO and others from the strata which have been thought to be of Paleozoic. The stratigraphic horizons shown by the fossils are consistent with the structural analysis by KIMURA and others.Strata, which change gradually to the Ryoke metamorphic rocks, contain the Upper Triassic conodonts and are probably covered conformably by the strata with the Upper Jurassic ammonoid. Weakly metamorphosed strata near the Sambagawa zone are overlain conformably by the Upper Triassic strata. Therefore, it became very clear that the Ryoke and Sambagawa “metamorphic” zones have suffered from the Cretaceous foldings as proposed by KOBAYASHI.The Paleozoic and Mesozoic strata in the Sangun-Yamaguchi and the Sambagawa-Chichibu zone were folded successively from the Late Permian to the Cretaceous time to form composite fold systems. On the other hand, strata in the Sambosan and the Shimanto zone were folded in each very short folding stage and formed isoclinal folds with very short wave-length.When the Triassic subduction zone was situated to the oceanic side of ancient Japan, the Sambosan zone-non-fold zone-, the Kurosegawa-fold zone-, the southern Yamaguchi-northern Chichibu-non-fold zone-, and the northern Yamaguchi-Hida zone-intense fold zone are arranged from the oceanic to the continental side. The distribution of the deformation zones has not been produced only by the compression due to the subduction of oceanic plates.

This paper describes the ordering mechanisms observed in Li ferrite powder samples with different particle sizes and aggregation states, as well as in sintered pellets. Measurement of ordering rates in the powder samples and observation of chemically etched surfaces of partially ordered pellets indicate that the ordering proceeds by a nucleation-growth mechanism and that the ordering initiates at grain boundaries and prevails into the inner part of the grains. In powder samples, surfaces as well as grain boundaries contribute to the initiation of ordering but their temperature dependences are different. The activation energy of the ordering is calculated to be 192 kj/mol.

Different LPS was shown to have a relatively different proportion of O-specific chain-less (R-form) LPS by polyacrylamide gel electrophoresis (PAGE) with sodium deoxycholate (DOC). By using DOC-PAGE, S-form LPS having O-chain with approximately 11 repeating units on average (S-Fr) and O-chain-less LPS (R-Fr) were separated from Escherichia coli UKT-B S-form LPS. Significantly stronger pyrogenicity was observed in R-Fr than in S-Fr when measured on the weight basis. Similar result was observed in Limulus test. Comparing biological activities of different S-form LPS, attention should be given to the amounts of co-existing R-form LPS.

The physical behavior of the mockup burnable poison rods, containing 0.5, 1.0, and 2.0 wt% Gd2O3 in natural uranium oxide pellets, has been studied in critical experiments. Specifically, the reacti...