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A composition-modulated Co–Ni laminated plating has been developed to prolong the lifetime of molds to be employed in continuous steel casting. We have investigated the relationship between the laminated structure and the mechanical properties of the plating films. The tensile strength of as-plated film was enhanced by the thinned thickness of the constituent layers, while the elongation received no effect of the thickness change of the constituent layer and remained almost stable in the range from 3 to 5%. Heat treatment at 400°C have brought about the improvement both in the tensile strength and the elongation. The improvement in the elongation was as remarkable as reached 13% in the film composed of layers with a thickness of 0.8 µm. The layer with low Ni content had an hcp structure, and that with high Ni content produced two phases of the hcp and fcc structures in the as-plated state. By the heat treatment, the high Ni-content layer turned into the single fcc phase, while the low Ni-content layer kept the hcp phase, and accordingly, the film structure changed into the one where the lamination of the hcp and fcc layers was distinct. The fact that the fcc layers, which was easily deformed, were formed continuously in the lateral direction, was seemed to contribute to the significant improvement in the elongation after heat treatment.

With the aim of extending the lifetime of molds used for continuous steel casting, we developed a composition-modulated Co-Ni alloy plating with alternately laminated layers of different compositions. Alloy films with laminated structures comprising few-micrometer-thick layers were formed using a single plating bath by periodically altering the agitation intensity in the bath during plating. The hardness of the as-plated composition-modulated Co-Ni alloy film was 350 HV, which was higher than that of a conventional non-laminated Co-Ni alloy plating film. Heat treatment slightly decreased the hardness. Nevertheless, the composition-modulated film exhibited higher tensile strength and higher hardness than the conventional alloy film after heat treatment at temperatures of 200-700 ℃. The breaking elongation of the composition-modulated film increased to 30% after heat treatment at 700 ℃. Finally, the composition-modulated Co-Ni alloy plating was applied to a mold surface, which was then used for continuous steel casting. It exhibited excellent resistance against crack formation by thermal shock resulting from contact with molten steel during continuous casting.

Shape-controlled Pt nanoparticles were electrochemically prepared on a graphite plate by galvanostatic electrolysis using an electrolytic cell containing a graphite plate cathode and a Pt sheet anode. The galvanostatic electrolysis was performed in a 0.5 M HNO 3 solution at 50 °C, and cubic nanoparticles were obtained by appropriately controlling cathodic and anodic current densities only. An extremely small amount of Pt ions produced by oxidative dissolution of the Pt anode diffused to the graphite cathode through the electrolyte solution and were reduced to form Pt nanoparticles having a cubic structure. Balancing the reduction rate of Pt ions at the graphite cathode and the dissolution rate of the Pt anode significantly influenced the shape of deposited Pt nanoparticles.

Introduction Shape-controlled Pt nanoparticles such as the cubic structure composed of only (100) plane and tetrahedral structure composed of only (111) plane have been studied because it was known that catalytic activity depended on crystal plane and was enhanced by a specific crystal structure. The commonly used method of shapecontrolled Pt nanoparticles is chemical reduction with organic stabilizers. However, the organic stabilizers are difficult to be removed and inhibit catalytic activity. Therefore, a preparation method without any organic stabilizer is desirable. In the present research, we prepared cubic Pt nanoparticles without any stabilizer by galvanostatic electrolysis in Pt-free acid solutions. The prepared cubic Pt nanoparticles were characterized by spectroscopic and electrochemical measurements.

To determine the efficacy and safety of 2 doses of gadobutrol 1.0 M (0.1 and 0.2 mmol/kg body weight [BW]), compared with gadoteridol 0.5 M (0.2 mmol/kg BW), in contrast-enhanced magnetic resonance imaging (CE-MRI) of brain metastases in patients with known or suspected brain metastases from systemic malignancies. The study also compared the usefulness of gadobutrol in treatment planning for stereotactic radiosurgery (SRS).This was a Phase II/III, multicenter, single-blind, randomized, controlled, crossover, intraindividual comparison study. Each patient underwent one MRI study examination with gadobutrol and the other with gadoteridol, each at a dose of 0.1 mmol/kg BW, administered twice, for a total dose of 0.2 mmol/kg BW. Image acquisition was carried out after the first and second doses of gadobutrol, but only after the second dose of gadoteridol. Contrast agents were assigned in a randomized order and their administration separated by an interval of 1 to 14 days. Images were evaluated through blinded readings by 3 independent experienced radiologists. Treatment planning for SRS was assessed in a blinded manner, as a consensus between a diagnostic neuroradiologist and a radiation oncologist, in addition to the clinical investigator's assessment. The safety and tolerability of gadobutrol and gadoteridol were evaluated in all patients who received the study drugs. The primary efficacy variable was the number of lesions detected in CE-MRI images; the secondary efficacy variables were the degree of contrast enhancement and border delineation of lesions, and experts' confidence in treatment planning for SRS.A total of 175 patients were enrolled and randomized, with 164 (93.7%) included in the safety analysis set, and 151 (86.2%) evaluable in the efficacy analysis. The mean number of detected lesions per patient using the average of the 3 blinded readers was 6.28, 6.92, and 6.87 for gadobutrol 0.1 and 0.2 mmol/kg BW, and gadoteridol 0.2 mmol/kg BW, respectively. Noninferiority of gadobutrol (both doses) to gadoteridol 0.2 mmol/kg BW was demonstrated. The degree of contrast enhancement and the border delineation of each lesion were categorized as "good" or "excellent" for most lesions for both agents. Almost all enhanced images were rated as "confident" in treatment planning for SRS. Sixty-five (43%) and 62 (41%) patients in the gadobutrol 0.1 and 0.2 mmol/kg BW groups, respectively, were selected as eligible for SRS treatment. The percentage of images assessed as "gadobutrol was better than gadoteridol" was higher than that assessed as "gadoteridol was better than gadobutrol" for both doses of gadobutrol. Eight adverse events were reported as being related to the study drug in 7 patients (4.3%) in each group.In this study, a single dose of gadobutrol was shown to be noninferior to a double dose of gadoteridol at detecting brain metastases, and could be effectively used for treatment planning in patients eligible for SRS. A dose of gadobutrol 0.1 mmol/kg BW is recommended as the clinical dose for the detection of brain metastases.

We have developed a novel preparation method for Pt-based nanoparticles by means of double potential step electrolysis (DPSE), in which Pt–Ni alloy deposited at the first step and Ni dissolved at the following step. A cycle of the DPSE in a nickel plating bath containing PtCl 6 2− led to the formation of the Pt–Ni nanoparticles with size of about 5.4 ± 1.5 nm, which gradually grew up with repeating the DPSE process, and surface Ni content of the particles by XPS was controllable by changing some parameters of the DPSE. The Pt–Ni nanoparticles deposited by the DPSE were covered with a Pt skin layer, which influence the improvement of both catalytic activity for oxygen reduction reaction (ORR) and corrosion resistance. The Pt–Ni nanoparticles by the DPSE exhibit ca. two times higher electrocatalytic activity for ORR than Pt nanoparticles, and further, of which catalytic activity was maintained high even with more than 1000 cycles of potential cycling test in H 2 SO 4 solution, showing good corrosion resistance.

It is well known that the adhesion strength of metal plating film on Al substrate should be remarkably improved by introducing double zincate treatment as a pretreatment process for metal plating on Al. At each step of alkaline etching, desmutting, the first zincate treatment, HNO3 dipping, and the second zincate treatment in the double zincate process, depth profiles and the chemical state of the surface elements were extensively measured by XPS. A set of surface structure models in the process was proposed to explain the improvement of the adhesion strength by double zincate treatment.By dipping the first zincate film in HNO3 solution, a granular zinc deposit of about 1 μm thickness, roughly deposited on Al passivation film at the first zincate treatment, was dissolved, and zinc nano-particles were believed to be concurrently formed in the Al passivation film of about 3nm thickness. In the second zincate treatment the nano-particles should be exposed to the second zincate solution to act as nuclei for formation of a highly uniform and thin zinc film. The zinc particles were so close to the metallic Al substrate, that Dipolar coupling such as Alδ+…Oδ&minus…Znδ+ would act to improve the adhesion strength of double zincate film on Al substrate.

Beta-titanium alloy bolts were developed with cold forging process. It was formerly difficult to manufacture beta-titanium bolts by cold forging, because beta-titanium alloy is easy to wear with dies. Now the lubricant coating of beta-titanium material and new cold forging processes are developed, resulting in manufacturing cold-forged beta-titanium bolts. It is confirmed to be able to mass-produce beta-titanium bolts. The beta-titanium bolts could be strengthened up to 800∼1200 MPa by heat treatments. It is, however, essential to control both the tensile strength and ductility, depending on uses.

The process of cathodic electrolytic formation of molybdenum oxide films from molybdate-citrate bath was investigated using Hull-Cell test, cathodic polarization measurement and UV absorption spectra measurement of the solution. pH, temperature and the concentration ratio of citrate ions to that of molybdate ions were changed. Chemical states of the deposited films were evaluated by XPS (X-ray photoelectron spectroscopy). The results of Hull-Cell test and cathodic polarization curves showed that molybdenum oxide film was deposited in the presence of citrate ions in the bath and the deposition rate was related to the bath pH and temperature of the solution. UV spectra indicated the formation of citrate-molybdate complexes which induce the deposition of molybdate oxide films. From the XPS analysis, the film was found to be a layered structure of Mo/MoO2/MoO3, in which metallic Mo was detected only on the substrate of Iron family elements, Ni, Fe, and only the second layer of MoO2 grew thicker by electrolysis.

Physicochemical and electrochemical hydriding-dehydriding characteristics of amorphous MgNi x (x=1.0, 1.5, 2.0) alloys prepared by mechanical alloying have been investigated. It was found that the increase of Ni content in the alloys resulted in greatly enhanced kinetics for both absorption and desorption of hydrogen, while the saturation capacity showed the reverse tendency. Charge–discharge tests showed that the increase in Ni content lead to a significant enhancement in cycle performance of MgNi x alloy electrodes. X-ray photoelectron spectroscopic and X-ray excited Auger electron spectroscopic investigations indicated the existence of a significantly thicker Ni-enriched layer for the MgNi1.5 and MgNi2.0 alloys than for the MgNi alloy. These results reveal that excess of Ni in MgNi x alloys may improve the cycle performance of alloy electrodes by suppressing the segregation of Mg during electrochemical cycling, and the Ni in the topmost surface layer is mainly responsible for the improvement in the kinetics of hydrogen absorption.

V-based TiV 2.1 Ni 0.3 alloy with high hydrogen storage capacity was surface-modified by ball-milling with amorphous MgNi alloy prepared by mechanical alloying. In charge–discharge cycle measurements, the decrease in discharge capacity for the prepared TiV 2.1 Ni 0.3 –MgNi composites was effectively suppressed in comparison with the TiV 2.1 Ni 0.3 alloy. In particular, ball-milling for 3 h is the most effective in the present study. This was explained by surface analyses with EPMA mapping and X-ray photoelectron spectroscopy (XPS). Changes in the EPMA maps, XPS spectra and depth profiles of the surface alloy components suggested that the ball-milling caused the mutual diffusion between Mg and a little of the Ni components in the MgNi alloy and Ti and V components in the TiV 2.1 Ni 0.3 alloy at the interface between both alloys. In addition, stable time course of rest potential for the TiV 2.1 Ni 0.3 –MgNi composite electrodes immersed in 6 M KOH solution also showed the effectiveness of the surface modification with ball-milling.

The hydriding and structural characteristics of amorphous MgNix alloys prepared by mechanical alloying have been investigated with charge–discharge tests and X-ray photoelectron spectroscopy (XPS) in combination with X-ray excited Auger electron spectroscopy (XAES). It was found that the increase in Ni content lead to a significantly enhancement in cycle performance of MgNix alloys. XPS and XAES investigations indicated the existence of a significantly thicker Ni enriched layer for the MgNi1.5 and MgNi2.0 alloys than that for the MgNi alloy. These results reveal that excess of Ni in MgNix alloys may improve the cycle performance of alloy electrodes by suppressing the segregation of Mg during electrochemical cycling.

MgNi-graphite composites prepared by ballmilling were investigated in detail, with emphasis given to the relation between the structural characteristics and the hydrogen-absorbing properties. It was found that there was an optimal ballmilling time for the preparation of MgNi-graphite composites with enhanced electrode performance when the composite exhibited a saturation capacity of hydrogen absorption virtually identical to that of the MgNi alloy, and the modification of graphite was limited to the surface layer of the MgNi alloy. Raman and X-ray photoelectron spectroscopic investigations on the composites indicated a decline in the {pi} electron character of graphite and changes in the chemical states of the constituents on the alloy surface, suggesting the possibility of charge transfer between graphite and the MgNi alloy during ballmilling, which resulted in an increase in the surface Ni/Mg ratio.

39 infants underwent conventional and power Doppler sonography (PDUS). In 25 normal cases, PD US clearly visualized the main trunks and medium sized branches of intracranial arteries. Prominent lentriculo-striate arteries and thalamostriate arteries were also visualized. In 14 cases with intracranial abnormalities, PDUS was useful to detect the tumor vessels, cerebral infarction and intra-cranial hemorrhage. PDUS is suggested to be a useful tool for visualizing intracranial arteries and diagnosing intracranial abnormalities of infants.

An amorphous MgNi alloy prepared by mechanical alloying has been investigated by means of X-ray photoelectron spectroscopy (XPS) and X-ray induced Auger electron spectroscopy (XAES) in combination with an Ar + sputtering technology. At the top surface (ca. 30 A), Mg was dominant and existed in oxide forms while Ni mainly existed in the metallic state. Underneath the top surface, there was a layer enriched with metallic Ni which penetrates to more than 150 A. Such a distribution of Mg and Ni at the surface layer tightly correlates to the unique hydriding and dehydriding properties of the amorphous MgNi alloy.

Bilirubin oxidase obtained from Trachyderma tsunodae K-2593 is a multi-copper enzyme which has type 1:type 2:type 3 copper atoms in the ratio 1:1:2. Anion binding properties of bilirubin oxidase were investigated to determine the structural and functional properties of bilirubin oxidase. The anions N3−, SCN−, F−, Cl−, and Br− were non-competitive inhibitors against the substrate, bilirubin ditaurate, and the inhibition constants of the anions were in the following order: N3−

In the electrodeposition of NiP alloy from a Ni-citrate bath, changes in P content and current efficiency of NiP deposits with plating variables such as H2PHO3 concentration, current density, bath pH and temperature were investigated. P content of the deposits was found to be constant around 25 at.% in a wide range of plating conditions. It was concluded that NiP alloy electrodeposition is controlled by Ni deposition rate and by the strong interaction between P and Ni, and that NiP alloy is formed through a direct deposition mechanism.

Examination was made of 1,2-asymmetric induction in the addition of alkyl radicals to γ-oxy-α,β-unsaturated ester derivatives 1 and 2 prepared from ethyl lactate and (R)-2,3-O-isopropylideneglyceraldehyde 3, respectively. The addition reactions of hexyl, cyclohexyl and 3-phenylpropyl radicals to (Z)-2 derived from aldehyde 3 gave β-addition products with syn-stereoselectivity (syn : anti= 8.6 : 1—syn only). The reactions of (E)-2 where non-stereoselective. Based on allylic strain, a transition-state model for the syn-stereoselectivity is proposed. 1,2-Asymmetric induction was carried out in radical cyclisation to synthesize active cyclohexane derivatives.

This article summarizes our free-radical approach to the general synthesis of fluorine-substituted cyclic compounds. Radical cyclization reactions of substrates containing the fluorine substituent on the initial radical site (CF3-C·, -CF2-C·) or the radical acceptor (Fn-C=C, CF3-C=C) proceeded effectively to give fluorine-substituted cyclopentane, cyclohexane, tetrahydrofuran and tetrahydropyran derivatives. In many cases, fluorine substituents exert no effect on the reactivity and the regioselectivity of the radical cyclization. In particular, an intermediary β-fluorine-substituted carbon radical is synthetically useful since ordinary carbanion chemistry is ineffective in forming C-C bond at the carbon β to the fluorine substituent.

A highly diastereoselective synthesis of functionalized trans gem-difluorocyclopropane carboxylate 3 was achieved through sequential Michael addition of lithium enolate of homochiral N-acylimidazolidinone 2 with 2,4,6-trimethylphenyl (TMP) 4-bromo-4,4-difluorocrotonate 1 and triethylborane-mediated intramolecular substitution reaction.

Regio- and stereoselective formation of the functionalized gem-difluorocyclopropane derivative was achieved through the Michael addition of lithium enolate of ester or amide with 4-bromo-4,4-difluorocrotonate 1 followed by the triethylborane-O 2 mediated intramolecular substitution reaction.

Electroplated films obtained from chromic acid plating baths containing NaNO3 were investigated using XPS analysis and X-ray diffraction.When the concentration of NaNO3 in the plating bath was raised to 4mM, the amount of nitrogen involved in the films increased to 4.2at%. Binding energy of N 1s and Cr 2p3/2 observed on XPS spectra for films indicated the existence of a kind of Cr-N compound. X-ray diffraction patterns showed that as-deposited film had hcp crystal structure and did not contain chromium nitrides (Cr2N or CrN). With heat treatment at 600°C for 4 hours the crystal structure changed from an hcp deposit to bcc chromium including chromium nitride.

Trifluoromethyl- or difluoromethylene-substituted alkyl radicals (CF 3 C or CF 2 C) and trifluoromethyl- substituted alkenyl radicals (CF 3 CC) cyclize effectively intramolecularly to allow the synthesis of fluorine- substituted cyclic compounds. Radical reactions of thiocarbonylimidazolide derivatives ( 7a,b, 13a–d, 14e,f ) gave CF 3 -substituted cyclopentane derivatives ( 22a, 25a–d ) or cyclohexane derivatives ( 22b, 26e,f ) via 5- or 6- exo selective cyclization. CF 3 -substituted cyclopentene derivatives ( 27a,b ) or cyclohexene derivatives ( 27c ) were also obtained from alkenyl iodides ( 17a–c ) via radical cyclization. Cyclopentane derivatives ( 29a–f, 31 ) containing the CF 2 CO 2 Et group were synthesized by Reformatsky reaction and radical cyclization.

Radical cyclizations were effectively applied to systems containing fluoroolefins (α-fluoro-α, β-unsaturated ester, fluoroallyl acetate, gem-difluoroolefin, and fluorine-substituted unsaturated lactone) for the synthesis of ring compounds containing fluorine-substituted groups.

Addition reactions of alkyl radicals to chiral (Z)-α,β-unsaturated ester derivatives obtained from (R)-2,3-O-isopropylidene glyceraldehyde proceeded with high stereoselectivity (1,2-asymmetric induction).

Simmons-Smith reactions of fluoroallyl alcohols and their derivatives with excess Zn-Cu and CH2I2 or Et2Zn and CH2I2 provided fluorocyclopropane derivatives. Diastereoselective cyclopropanation of the fluoroallyl alcohol derivative obtained from (R)-2, 3-O-isopropylidene glyceraldehyde was successfully carried out to give the optically active fluorocyclopropane derivative in high selectivity (>98% de).

Trifluoromethyl- or difluoromethylene-substituted alkyl radicals (CF 3 C or CF 2 C) and trifluoromethyl- substituted alkenyl radicals (CF 3 CC) cyclize effectively intramolecularly to allow the synthesis of fluorine- substituted cyclic compounds. Radical reactions of thiocarbonylimidazolide derivatives ( 7a,b, 13a–d, 14e,f ) gave CF 3 -substituted cyclopentane derivatives ( 22a, 25a–d ) or cyclohexane derivatives ( 22b, 26e,f ) via 5- or 6- exo selective cyclization. CF 3 -substituted cyclopentene derivatives ( 27a,b ) or cyclohexene derivatives ( 27c ) were also obtained from alkenyl iodides ( 17a–c ) via radical cyclization. Cyclopentane derivatives ( 29a–f, 31 ) containing the CF 2 CO 2 Et group were synthesized by Reformatsky reaction and radical cyclization.

Regio- and stereoselective formation of the functionalized gem-difluorocyclopropane derivative was achieved through the Michael addition of lithium enolate of ester or amide with 4-bromo-4,4-difluorocrotonate 1 followed by the triethylborane-O 2 mediated intramolecular substitution reaction.

The Simmons-Smith reactions of Z- and E-allyl alcohol derivatives 6 derived from (R)-2,3-O-isopropylideneglyceraldehyde (6) were used for the synthesis of optically active cis- and trans-1,2-disubstituted cyclopropane derivatives. Reaction of 6 with diethyl zinc and diiodomethane gave cyclopropane derivatives 7 in 84% to quantitative yields with 35 to ≃100% des. Identical facial selectivities toward the double bonds, 1re-2si for Z-6 and 1re-2re for E-6, were observed in the cyclopropanations. The diastereoselectivity was dependent on the protecting group on the terminal allylic oxygen (R of 6, TBDPS>MOM>Bn) and on the stereochemistry of the double bond (Z >E). For TBDPS ethers Z-and E-6c, cis- and trans-7c were obtained as single distereomers, respectively. It was clearly demonstrated that the stereoselectivity of the cyclopropantion is controlled by the directing effect of the allylic oxygen (O-1) of the dioxolane ring, which coordinates to the reagent. The terminal allylic oxygen (O-2) lowered the diastereoselectivity. This reaction was applied to the synthesis of optically active cyclopropane analogs of γ-aminobutyric acid (GABA) 18,22, and ent-22

This article summarizes our free-radical approach to the general synthesis of fluorine-substituted cyclic compounds. Radical cyclization reactions of substrates containing the fluorine substituent on the initial radical site (CF3-C·, -CF2-C·) or the radical acceptor (Fn-C=C, CF3-C=C) proceeded effectively to give fluorine-substituted cyclopentane, cyclohexane, tetrahydrofuran and tetrahydropyran derivatives. In many cases, fluorine substituents exert no effect on the reactivity and the regioselectivity of the radical cyclization. In particular, an intermediary β-fluorine-substituted carbon radical is synthetically useful since ordinary carbanion chemistry is ineffective in forming C-C bond at the carbon β to the fluorine substituent.