Recrystallization and grain growth are important phenomena for controlling the mechanical and magnetic properties of steels through texture. Only a limited number of studies have been carried out on texture evolution during recrystallization and grain growth in heavily cold-rolled Si steel. The present study first focuses on clarifying the texture evolution during normal grain growth, followed by an investigation into the development of the {

}<148> component during recrystallization. The {}<148> component is remarkably developed during normal grain growth after the completion of recrystallization. At just fully recrystallized stage, the diameters of the {}<148> grains were larger than that of the grains with other orientations. Therefore, the {}<148> grains significantly grew owing to the size advantage.

Just at the commencement of recrystallization, differences in grain diameter of recrystallized grains in terms of crystal orientation were not detected. However, it is worthwhile to mention that the nucleation of {

}<148> recrystallized grains is unexpectedly fast in heavily cold-rolled Si steel. Recrystallized {}<148> grains were observed to nucleate in the deformed α-fiber grains, especially near the grain boundaries. Nuclei with {}<148> orientation grow easily due to the high mobility of the interface between the recrystallized/non-recrystallized grains and the high driving force. Consequently, the diameter of a {}<148> recrystallized grain becomes relatively large upon the completion of recrystallization. This contributes to the selective grain growth during the normal grain growth stage because of the size effect.

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Recrystallization texture is essential to control the mechanical and magnetic properties of steels. Both γ-fiber (ND//<111>) and α-fiber (RD//<011>) textures are known to develop during the rolling process of bcc iron. Recrystallization behavior from γ-fiber has been extensively studied. On the other hand, recrystallization behavior from α-fiber, in particular after heavy cold rolling reduction, has not been sufficiently clarified. In this study, recrystallization behavior from α-fiber, focusing on the formation of {

}<148> recrystallized grain, was investigated by means of EBSD and TEM. {}<148> region already existed in the vicinity of deformed grains having upper α-fiber orientation ({100}<011> ~ {211}<011>). TEM observation revealed the existence of the lamellar structure with {}<148> relatively fine dislocation cells in the {211}<011> deformed grains. With the progress of the recovery, {}<148> subgrains (dislocation cells) are postulated to easily form and are surrounded by the deformed matrix grains with high angle interface. Thus, it is easy to form the recrystallization nuclei having the potential to grow with the sake of both high driving force and high interface mobility. At the early stage of recrystallization, {}<148> recrystallized grains developed in {211}<011> deformed grains. At the later stage, {}<148> recrystallized grains from {211}<011> deformed grains encroach {100}<011> deformed grains and new {}<148> recrystallized grains developed in {100}<011> deformed grains.

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This study aimed to clarify the influence of crystallized particles in Pb-free Cu alloys (JIS CAC

and CAC901) on the corrosion in a chloride aqueous solution. CAC, CAC901, CAC403, and CAC406 were used as Cu alloy specimens. Cu₂S, Bi, and Pb were used as simulated crystallized substances of CAC, CAC901 and CAC406, respectively, and Cu was used as the simulated matrix. All the corrosion tests described below were conducted in a 3.0 mass％NaCl solution at 30℃. The corrosion rates of CAC and CAC901 specimens were almost the same as that of CAC403, but lower than that of CAC406 specimen in the early stages of the immersion-corrosion test. For galvanic corrosion tests, the galvanic current density flowing between the simulated crystallized substance specimens (Cu₂S or Bi) and the simulated matrix specimen was much lower than the reduction current density of dissolved oxygen. In the case of Pb, the galvanic current flowed from the simulated matrix specimen to the Pb specimen, and the current density on the Pb specimen was significantly larger than the reduction current density of dissolved oxygen. It was concluded that susceptibility to galvanic corrosion between matrix and Cu₂S or Bi were much smaller than that of Pb, and those crystallized substances did not significantly affect the corrosion behavior of CAC and CAC901.

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The research aimed to investigate the corrosion behavior of Cu–Sn–Zn–S alloy（as one of lead–free Cu alloys）in CuCl₂ aqueous solutions. JIS CAC

（Cu–Sn–Zn–S alloy）, Cu and Sn were used as specimens. Test solutions were CuCl₂ ＋ NaCl solutions whose Cu^2＋ and Cl⁻ concentrations were controlled. A polarization curve of each specimen in each solution was measured. The results were described as follows：Increase in Cu^2＋ concentration accelerated cathodic reaction and made corrosion potential of Cu and CAC specimens higher, however hardly changed shapes of the anodic polarization curves. On the other hands, increase in Cl⁻ concentration accelerated anodic reaction and decrease corrosion potential of Cu and CAC specimens. 1.0 mass％ CuCl₂ solution which generally employed in the jet–in–slit test facilitated to form corrosion product layer consisting of CuCl. Sn was concentrated in the corrosion product layer formed on CAC specimen. The particles of the corrosion product formed on CAC was finer and the corrosion product layer was denser than that on Cu.

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Recrystallization and grain growth are important phenomena for controlling the mechanical and magnetic properties of steels through texture. Only a limited number of studies have been carried out on texture evolution during recrystallization and grain growth in heavily cold-rolled Si steel. The present study first focuses on clarifying the texture evolution during normal grain growth, followed by an investigation into the development of the {

}<148> component during recrystallization. The {}<148> component is remarkably developed during normal grain growth after the completion of recrystallization. At just fully recrystallized stage, the diameters of the {}<148> grains were larger than that of the grains with other orientations. Therefore, the {}<148> grains significantly grew owing to the size advantage.

Just at the commencement of recrystallization, differences in grain diameter of recrystallized grains in terms of crystal orientation were not detected. However, it is worthwhile to mention that the nucleation of {

}<148> recrystallized grains is unexpectedly fast in heavily cold-rolled Si steel. Recrystallized {}<148> grains were observed to nucleate in the deformed α-fiber grains, especially near the grain boundaries. Nuclei with {}<148> orientation grow easily due to the high mobility of the interface between the recrystallized/non-recrystallized grains and the high driving force. Consequently, the diameter of a {}<148> recrystallized grain becomes relatively large upon the completion of recrystallization. This contributes to the selective grain growth during the normal grain growth stage because of the size effect.

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We aimed to understand the corrosion behavior of Pb-free Cu alloys (Japan Industrial Standards (JIS) CAC

and CAC901) and the substances (Cu₂S and Bi, respectively), which are in the alloys as particles, in a 3.0 mass％ NaCl aqueous solution. The corrosion behavior of the Pb-free Cu alloys and the substances were compared with those of a Cu alloy (JIS CAC406), which Pb detected as crystallized particles in it, and a Cu alloy (JIS CAC403) without any crystallized substances. Cu₂S specimens were produced by sintering Cu₂S powders. Bi specimens were produced by Bi electro-plating on Cu plates.

The measured corrosion potentials of CAC

, CAC901, and CAC403 were close to that of Sn instead of Cu. The anodic polarization curves of all the Cu alloy specimens showed that the anodic current density increased rapidly at a potential above −0.20 V vs. Ag/AgCl, and the rapid increase in the current density was similar to that of Cu. Therefore, it was concluded that the increase in the current density of the Cu alloys results from the dissolution of Cu in a matrix. Cu₂S was converted into CuS during the anodic reaction. However, the corrosion potential of Cu₂S was higher than those of Cu and CAC. Therefore, it was concluded that the Cu₂S particles in CAC act as cathodic sites and remain stable during the natural corrosion. The corrosion potential of Bi was higher than that of CAC901 and slightly lower than that of Cu. At the potentials below −0.10 V vs. Ag/AgCl, Bi was thought to be covered with a passive Bi₂O₃ film and the passive film was expected to protect Bi from corrosion. Therefore, it was concluded that the Bi particles in CAC901 hardly suffer severe corrosion. The corrosion potential of Pb was lower than those of the Cu and Cu alloys, expect for CAC406. In addition, Pb exhibited a large anodic current density and dissolved actively around the corrosion potential of Cu. Therefore, it was concluded that the Pb particles dissolved preferentially during the corrosion of CAC406 owing to galvanic corrosion. Finally, it was concluded that the Cu₂S and the Bi particles in CAC and CAC901, respectively, hardly suffer severe corrosion compared with the Pb particles in CAC406 in chloride-containing aqueous solutions such as sea water.

 

Mater. Trans. 58(2017) 1679-1686に掲載

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Recrystallization texture is essential to control the mechanical and magnetic properties of steels. Both γ-fiber (ND//<111>) and α-fiber (RD//<011>) textures are known to develop during the rolling process of bcc iron. Recrystallization behavior from γ-fiber has been extensively studied. On the other hand, recrystallization behavior from α-fiber, in particular after heavy cold rolling reduction, has not been sufficiently clarified. In this study, recrystallization behavior from α-fiber, focusing on the formation of {

}<148> recrystallized grain, was investigated by means of EBSD and TEM. {}<148> region already existed in the vicinity of deformed grains having upper α-fiber orientation({100}<011>~{211}<011>). TEM observation revealed the existence of the lamellar structure with {}<148> relatively fine dislocation cells in the {211}<011> deformed grains. With the progress of the recovery, {}<148> subgrains (dislocation cells) are postulated to easily form and are surrounded by the deformed matrix grains with high angle interface. Thus, it is easy to form the recrystallization nuclei having the potential to grow with the sake of both high driving force and high interface mobility. At the early stage of recrystallization, {}<148> recrystallized grains developed in {211}<011> deformed grains. At the later stage, {}<148> recrystallized grains from {211}<011> deformed grains encroach {100}<011> deformed grains and new {}<148> recrystallized grains developed in {100}<011> deformed grains.

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Recently, a newly developed lead-free bronze casting alloy was designated as CAC

under Japanese Industrial Standards. CAC has a unique metallographic feature: tiny sulfide（Cu₂S and ZnS）particles are dispersed in the bronze matrix, unlike conventional copper alloys. Earlier research results demonstrated that the sulfides have different electrochemical properties from those of the bronze matrix. At or under −1.20 V vs. Ag/AgCl, Cu₂S suffered reduction and dissolution in neutral NaCl aqueous solution under cathodic polarization. The Cu₂S dissolution reaction is regarded as affecting the alloy surface morphology in cathodic treatments such as electroplating. This study was conducted to elucidate effects of the sulfide on Cu-, Ni-, and Cr-electroplatings on CAC. Results show that Cu-plating and Ni-plating affected the sulfide dissolution only slightly. Their plating surfaces were smooth and bright. However, the Cr-plated alloy surface was fogged. The fogged surface resulted from Cr cluster deposition on the sulfides. Presumably, the sulfide dissolved under the cathodic conditions was oxidized to HSO₄^- by Cr⁶⁺. The HSO₄^- behaved as catalyst for Cr deposition. Cu-plating or Ni-plating before the Cr-plating was found to be effective for obtaining a smooth and bright Cr-plating surface on CAC.

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The X-ray elastic constants of sintered silicon nitride were measured for the diffraction plane (323) by using Cu-Kα radiation and for () by using Cr-Kα radiation. The values of E/(1+ν) (E=Young's modulus, ν=Poisson's ratio) were nearly identical for both planes, and were larger than the mechanically measured value. The residual stress on the lapped and ground surfaces was measured both with (323) and () diffractions. The measured values were all compression. The compressive stress for () plane was three to four times larger than that for (323) plane, which indicated a steep decrease of compression in the subsurface layer. The compressive residual stress in the direction perpendicular to the grinding direction was about twice the value in the grinding direction.

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NCC-CO-, an anti-carcinoembryonic antigen (CEA) monoclonal antibody (MoAb) showed a dose-dependent reactivity with standard CEA, but did not bind to the CEA anchoring with cell membranes. When LS 174T cells, one of the CEA-producing cells, were treated with phosphatidylinositol-specific phospholipase C, NCC-CO- MoAb recognized the released CEA containing glycosylphosphatidylinositol as well as the standard CEA. The binding activity of NCC-CO- MoAb with CEA was also demonstrated by the immunostaining of the LS 174T colorectal tumor xenograft tissues. The biodistribution study showed that NCC-CO- MoAb was mainly taken up by tumor and kidney, while the anti-hCEA MoAb was largely concentrated in liver and spleen rather than in the tumor. These results suggest that NCC-CO- MoAb recognizes the released CEA and gives an excellent tumor image in LS 174T tumor-bearing mice.

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Human serum albumin (HSA), one of the most abundant proteins in the circulation system, contains binding sites for a variety of drugs. The recent X-ray crystallographic data of HSA shows that the two major ligand binding sites, site I and site II, are located within specialized cavities in two separate subdomains, namely subdomain IIA and IIIA, respectively. Correctly folded single-residue mutants K199A, W214A, R218H and H242Q were overexpressed. The primary binding constant for warfarin was decreased 2- and 3-fold by mutating Trp-214 and Arg-218, respectively, but was increased 4 and 6-fold by replacing Lys-199 and His-242, respectively. The constants for W214A and R218H responded to the pH-changes in a quantitatively different manner from that of K199A and H242Q. Thus, this parameter also showed heterogeneity in domain II in responding to the N to B transition. The single-mutants R410A, YA, YS and YF and the double-mutant R410A/YA were produced. We investigated, by ultrafiltration and CD, the high affinity binding of two representative site II-ligands, namely ketoprofen and diazepam. According to the crystal structure of HSA, the Arg-410 and Tyr- residues protrude into the center of site II (in subdomain IIIA), and the binding results showed that the guanidino moiety of Arg-410, the phenolic oxygen and the aromatic ring of Tyr- are important for ketoprofen binding. The guanidino moiety probably interacts electrostatically with the carboxyl group of ketoprofen, the phenolic oxygen could participate in hydrogen bonding to the ketogroup of the ligand, and the aromatic ring may participate in a specific stacking interaction with one or both of the aromatic rings of ketoprofen. In contrast, Arg-410 is not important for diazepam binding. The two parts of Tyr- interact favourably with diazepam and probably do so in principally the same way as with ketoprofen. In addition to its unique ligand binding properties, HSA also possesses an esterase-like activity, and studies with p-nitrophenyl acetate as a substrate showed that although Arg-410 is important, the enzymatic activity of albumin is much more dependent on the presence of Tyr-. Minor activity was detected when serine was introduced but not alanine or phenylalanine, in position .

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For about 6 months before, during and after the administration of a new drug named Phenelzine (Ep ), the writer investigated the effect of the drug on 16 out-patients and 4 in-patients of our clinic who were in depressive states. Each patient, for three times a day with each meal, was given a tablet which contained 15mg of Ep . Main results obtained are as follows.
1) The administration of the drug had a favorable influence on inhibition, however, had much less response on physical symptoms or sensations.
2) Among various kinds of depressive states marked reaction was noticed on neurotic depressive symptoms, while less reaction was noticed in periodic or phasic psychosis of the manic depressive type.
3) Since Ep has both sedative and stimulating effects for mental symptoms this remedy has distinctive features.
4) Generally speaking, Ep has minimal side-effects. In summary, Ep is deemed to be superior to any other antidepressant from the standpoint of its margin of safety.

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Crystallographic texture development during recrystallization in samples cold-rolled to 78, 87 and 96% thickness reduction R were measured using EBSD on an in-situ heating stage inside a field emission scanning electron microscope. Nucleation, recrystallization and grain growth of grains having {

}<148> orientation occurred intensely and steadily inside the deformed region. Through this phenomenon, grains having {}<148> showed larger average grain sizes than other textures at R = 87% and 96%. Due to the {}<148> texture component, the {111}<112> texture component, which is known as a high reduction emerging texture, weakened. At R = 76%, grains having Goss orientation were frequently observed. However, at R = 87% and 96%, the {111}<112> and the {}<148> texture components became dominant and the α* fiber was strengthened.

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The effect of Si and Al additions on the recrystallization behavior of severely cold-rolled Fe by 99.8% reduction was investigated in comparison with a previous study on pure Fe⁶⁾. In Fe-0.3mass%Si alloy, recrystallized grain with {} <011> and {} <148> preferentially nucleated at an early stage of recrystallization, and the texture did not changed substantially with the progress of recrystallization, which supports the oriented nucleation theory. The {} <148> texture significantly increased at the expense of recrystallized grains with {100} <023> and {322} <236> during normal grain growth. In Fe-0.3mass%Al alloy, dynamic recovery during heavy cold-rolling and substantial subgrain growth during low temperature annealing (350˚C) occurred, similar to the case of pure Fe and different from that of Fe-0.3mass%Si alloy. This is presumably because of the subtle influence of Al addition on cross-slip frequency and smaller solute-vacancy interaction as compared with Si addition. Furthermore, at the early stage of recrystallization, nuclei had similar orientations as cold-rolling texture. With the progress of recrystallization, {100} <012> and {111} <112> orientations intensified. In the following normal grain growth, {100} <012> texture intensified. However, the change in the texture during growth cannot be explained only by the size effect. A rigorous grain growth simulation model is required to explain the experimental facts by considering the dependency of grain boundary mobility and energy on grain boundary characteristics.

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In this study, we aimed to understand the corrosion behavior of Pb-free Cu alloys (Japan Industrial Standards (JIS) CAC

and CAC901) and their crystallized substances (Cu₂S and Bi, respectively) particles in a 3.0 mass% NaCl aqueous solution, in comparison with those of a Cu alloy (JIS CAC406), its crystallized substance (Pb) particles, and a Cu alloy (JIS CAC403) with no crystallized substances. A Cu₂S specimen was produced via sintering Cu₂S powders, and a Bi specimen was produced by Bi electro-plating on a Cu substrate. The measured corrosion potentials of CAC, CAC901, and CAC403 were close to that of Sn instead Cu. The current density peak near the corrosion potential of CAC403, which was the highest Sn concentration, was the largest in comparison with those of the other Cu alloys. Conversely, rapid increase in the current density, which was shown for all the Cu alloy at the potential above −0.20 V vs. Ag/AgCl, was similar to that of Cu. Therefore, it was concluded that these increase in current densities of Cu alloys was due to the dissolution of the Cu matrix. Cu₂S was converted into CuS during the anodic reaction. However, the corrosion potential of Cu₂S was higher than those of Cu and CAC. Therefore, it was concluded that the Cu₂S particles in CAC act as cathodic sites and remain stable during the natural corrosion. The corrosion potential of Bi was higher than that of CAC901 and slightly lower than that of Cu. Further, at the potentials below −0.10 V vs. Ag/AgCl, Bi was thought to be covered with the passive film of Bi₂O₃ that was expected to protect Bi from corrosion. Therefore, it was concluded that the Bi particles in CAC901 hardly suffer severe corrosion. The corrosion potential of Pb was lower than those of the Cu and Cu alloys expect for CAC406. In addition, Pb exhibited a large anodic current density and dissolved actively around the corrosion potential of Cu. Therefore, it was concluded that the Pb particles dissolved preferentially during the corrosion of CAC406 owing to the galvanic corrosion. It was finally concluded that the Cu₂S and the Bi particles in CAC and CAC901, respectively, hardly suffer severe corrosion than the Pb particles in CAC406 in chloride-containing aqueous solutions like sea water.

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In order to establish the contribution of Tyr of human serum album in (HSA) to specific drug binding, the effect to drug binding on the fluorescence spectrum of HSA in which Tyr was modified with p-nitrophenyl anthranilate (ANT-HSA) was studied by using various drugs (diazepam, chlordiazepoxide, fluenamic acid, indomethacin, azapropazone, phenylbutazone, warfarin, salcylic acid, ibuprofen, L-tryptophan, tolbutamide and sulfadimethoxine). Among these durugs, indomethacin and flufenamic acid strongly quenched the fluorescence of the anthraniloyl group of ANT-HSA at a molar ratio of 1.0, indicating that these drugs bind near the Tyr residue.

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The α-glucosidase gene (agdA) of Aspergillus nidulans has a single CGGN₈CGG type AmyR binding site in its promoter region. The binding site is functional in vivo as a cis-element responsible for induction by starch, and mutational studies indicated that both the CGG triplets are required for high-level induction. A part of AmyR (residues 1-; AmyR1-

411

), which was produced as a MalE fusion protein in E. coli, bound to the CGGN₈CGG site of the agdA promoter. DNA binding profiles to the mutant binding sites that lacked both or either one of the CGG triplets suggested that AmyR1-

411

can bind to a single CGG triplet site with low affinity and that two AmyR molecules cooperatively bind to the CGG direct repeat.

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The Experiences Questionnaire measures decentering, the state of observing thoughts and feelings as temporary events in the mind. This study developed the Japanese version of the Experiences Questionnaire (JEQ). The fit indices in confirmatory factor analysis (n=297) suggested an acceptable fit to a model consistent with the original. The correlations (n=) between the J-EQ and the Acceptance and Action Questionnaire- II, the Affective Control Scale, the Ruminative Response Scale, and the Cognitive Control Scale showed adequate construct validity. Internal consistency (n=) and test–retest correlations of factors (n=54) indicated good reliability of the J–EQ. The J–EQ can be used to examine the influence of decentering on psychopathology.

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Thirteen strains were isolated from different habitats, belonging to two genera, namely Conidiobolus and Basidiobolus, related to saprophytic Entomophthorales. Chitin flake colonization and agar-well diffusion tests were used to screen potential extracellular chitinase-producing strains in plate assays. Preliminary screening resulted in five chitinase producers that were further studied quantitatively. Results indicated that studied isolates of this group produced chitinase at different levels in chitin-containing as well as non-chitin-containing medium. Conidiobolus coronatus was found to be the most significant chitinase producer, giving 0.261 U/ml using colloidal chitin as a carbon source, among the isolates under study. This communication also reports the chitinolytic activity of Basidiobolus haptoporus, the effect of environmental and nutritional parameters on chitinase production, and utilization of fungal biomass as a carbon source, which hitherto had not been elaborated from this genus.

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