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For an Ir-doped TiO2(Ir:TiO2) photocatalyst, we examined the most dominant electron-transfer path for the visible-light-driven photocatalytic performance. The Ir:TiO2photocatalyst showed a much higher photocatalytic activity under visible-light irradiation than nondoped TiO2after grafting with the cocatalyst of Fe3+. For the Ir:TiO2photocatalyst, the two-step photoexcitation of an electron from the valence band to the conduction band through the Ir doping level occurred upon visible-light irradiation, as observed by electron spin resonance spectroscopy. The two-step photoexcitation through the doping level was found to be a more stable process with a lower recombination rate of hole–electron pairs than the two-step photoexcitation process through an oxygen vacancy. Once electrons are photoexcited to the conduction band by the two-step excitation, the electrons can easily transfer to the surface because the conduction band is a continuous electron path, whereas the electrons photoexcited at only the doping level could not easily transfer to the surface because of the discontinuity of this path. The observed two-step photoexcitation from the valence band to the conduction band through the doping level significantly contributes to the enhancement of the photocatalytic performance.

Background: The Philippines is ranked among the top countries with 200–300 annual deaths due to rabies. Most human rabies cases have been reported in remote areas, where dog surveillance is inadequate. Therefore, a strategy to effectively improve surveillance in remote areas will increase the number of detections. Detecting pathogens using portable real-time reverse transcription-polymerase chain reaction (RT-PCR) has the potential to be accepted in these areas. Thus, we aimed to develop an assay to detect the rabies virus (RABV) genome by combining the robust primer system LN34 with the PicoGene PCR1100 portable rapid instrument targeting RABV RNA (PCR1100 assay). Methods: Procedures were optimised using an LN34 primer/probe set, KAPA3G Plant PCR Kit (KAPA Biosystems), FastGene Scriptase II (NIPPON Genetics), and an artificial positive control RNA. Results: Positive control RNA showed an analytical limit of detection of 10 copies/µL without false positivity, generating results in approximately 32 min. Compared to dFAT or RT-qPCR using field samples, the sensitivity and specificity of the PCR1100 assay were 100%, and even lower copy numbers (approximately 10 copies/µL) were detected. Conclusions: This study demonstrated that the developed assay can detect rabies RNA in field samples. Because dog-mediated rabies is endemic in remote areas, the rapidity, mobility, and practicality of the PCR1100 assay as well as the high sensitivity of the LN34 system make it an ideal tool for the confirmation of rabies in these areas.

Photocatalytic overall water splitting into hydrogen and oxygen on RuO2-loaded Sm3+-doped CeO2was examined. Pure CeO2showed a negligible small activity, however Sm3+doped CeO2with heterogeneous doping structure synthesized by solid state reaction exhibited an efficient activity, whereas Sm3+-doped CeO2with homogeneous doping structure showed little activity when prepared by co-precipitation method. In this study, the relation between photocatalytic activity and surface doping structure was investigated.Particulate Sm3+-doped CeO2with heterogenous doping structure showed excellent photocatalytic activity for overall water splitting under UV-light irradiation. Interface between pure and Sm3+-doped CeO2phase plays an important role for separating photoexcited electron and hole, leading to sufficient photocatalytic activity for water splitting.

Understanding the details of the mechanism of water photo-oxidation on monoclinic bismuth vanadate (m-BiVO4) is intriguing for efficient oxygen (O2) evolution under solar light. Hydroxyl (OH) radical was confirmed in a photocatalytic system of m-BiVO4powders. OH radical is highly reactive to dimerize into hydrogen peroxide (H2O2), which is further oxidized into O2molecule. Therefore, O2evolution from OH radicals could be one of the plausible mechanisms. In the present study, to clarify the significance of O2evolution from OH radicals, O2molecules and OH radicals were generated by photoelectrochemical water oxidation on m-BiVO4electrode. The amounts of O2molecules and OH radicals were quantified by using an oxygen meter and a fluorescence probe method, respectively. The current efficiency of the photocurrent for the formation of OH radicals (∼0.06%) was much smaller than that for O2evolution (∼100%), indicating that O2evolution from OH radicals was not significant on m-BiVO4.

The electronic structure of a solid solution between GaN and ZnO, GaN-rich (Ga1−xZnx)(N1−xOx), was investigated by photoluminescence spectroscopy and a plane wave based density functional method. Photoluminescence excitation spectra (PLE) of (Ga1−xZnx)(N1−xOx) photocatalysts (x= 0.05−0.11) at 20 K had PLE edges in the UV region in addition to those of undoped GaN and Zn-doped GaN. However, the absorption edges appeared in the visible region, indicating that the intrinsic band gap of GaN-rich (Ga1−xZnx)(N1−xOx) solid solutions is derived from that of the GaN component. Photoluminescence (PL) bands of (Ga1−xZnx)(N1−xOx) photocatalysts were observed at 480 and 650 nm, suggesting that the luminescence originated from electron transitions from the conduction band to Ga vacancies as native defects, or to Zn acceptor levels as impurity levels. GaN-rich (Ga1−xZnx)(N1−xOx) material containing a large amount of oxygen is likely to produce an O donor level slightly below the conduction band minimum (CBM). The Zn acceptor level is likely to be filled with electrons derived from O donor levels or thermal excitation, suggesting that the absorption in the visible light region of this material occurs via electron transitions from the Zn acceptor level to the conduction band. The electronic structure and band gap narrowing are discussed in terms of density functional theory calculations using local nonstoichiometric defect structures modeled by Zn atom replacement, O atom replacement, or Ga atom vacancies.

Background: The Philippines is one of the major endemic countries for canine rabies in Southeast Asia. However, detailed description and analysis of laboratory-confirmed animal rabies are limited. Highly accurate surveillance requires a thorough understanding of the target area-specific problems and obstacles. Therefore, we aim to describe and analyze the rabies suspect animals in Central Luzon, Philippines, to clarify the characteristics of management and clinical signs by conducting interviews with the owners. Methods: We prospectively collected information on the rabies suspect animals submitted to the Regional animal laboratory in Central Luzon through passive laboratory-based rabies surveillance between 1st April 2019 and 30th September 2020. We performed active interviews directly or telephonically with the owner. The direct fluorescent antibody test was performed on the hippocampus, brain stem, and cerebellum for laboratory confirmation. Descriptive statistics were used to characterize the number of rabies cases according to management methods and characteristics of suspected animals during the observation period. Clinical symptoms of suspected rabid animals were analyzed by univariate logistic regression analysis. Results: There were 292 sample submissions during the study period. Of these, 160 were positive for dFAT. Samples of pet animals (85.3%) provided by owners or their acquaintances (59.2%) accounted for the majority of laboratory confirmed cases. Case mapping showed that more rabies-suspected cases were sent from areas near the regional laboratory than from those far from the laboratory, despite the incidence of rabies being high in these areas. The management and clinical symptoms of 227 animal cases showed that most owners were managing their animals at home and were allowing them to roam outside (69.6%) and be unvaccinated (78.9%). Rabid animals were more likely to manifest aimless running, restlessness, and agitation. Conclusions: Our study provided some features of animals with laboratory-confirmed rabies in Central Luzon. However, most of the samples were submitted from areas near the rabies diagnosis laboratory, and the number of samples submitted from remote areas was low. To improve the surveillance capacity, it is necessary to increase sample submissions from remote areas.

Photodeposited Rh/Cr2O3(core/shell) nanoparticles on a (Ga1-xZnx)(N1-xOx) photocatalyst are studied as a cocatalyst for overall water splitting. Irradiation of Rh-loaded (Ga1-xZnx)(N1-xOx) with visible light ( > 400 nm) in aqueous K2CrO4solution results in the formation of core/shell-structured nanoparticles consisting of a Rh core and Cr2O3shell through the site-selective photoreduction of CrO42-anions to Cr2O3on Rh nanoparticles. The shell thickness increases with concentration of K2CrO4in the reactant solution to a maximum of ca. 2 nm, at which a uniform Cr2O3coating is obtained. The Cr2O3shell suppresses water formation from H2and O2on Rh nanoparticles, allowing stoichiometric decomposition of pure water to be achieved. The core/shell structure also provides enhanced H2evolution compared to that of bare Rh nanoparticles.

Gallium nitride (GaN) powder was studied as a photocatalyst for overall water splitting. The photocatalytic activity of GaN for the reaction was found to be strongly dependent on the crystallinity of the material and the cocatalyst employed. Modification of well-crystallized GaN with Rh2−yCryO3nanoparticles as a cocatalyst for H2evolution resulted in the stable stoichiometric decomposition of H2O into H2and O2under ultraviolet irradiation (λ > 300 nm) by the band gap transition. RuO2modification did not bring about appreciable H2and O2evolution. Low-crystallinity GaN exhibits negligible activity for overall water splitting, regardless of the kind of cocatalyst applied.

Germanium nitride, -Ge3N4, is studied as a non-oxide photocatalyst for overall water splitting. Nitridation of GeO2at 1153 K for 10 h under a flow of NH3results in the production of well-crystallized -Ge3N4particles with a phenacite structure belonging to the hexagonal crystal system. Although the as-prepared -Ge3N4displays negligible activity for overall water splitting, the material becomes photocatalytically active under ultraviolet (UV) irradiation ( > 200 nm) when loaded with RuO2nanoparticles as H2evolution sites. The photocatalytic activity of RuO2-loaded -Ge3N4for overall water splitting is strongly dependent on the reaction conditions. The highest activity is obtained when the reaction is carried out in 1 M H2SO4aqueous solution. The rates of both H2and O2evolution decreases as the reaction progresses, attributable to photoreduction of O2, collapse of the catalyst surface by elusion of Ge cations, and loosened interfacial contact between the -Ge3N4and the loaded RuO2nanoparticles. Up to 80% of the initial activity can be recovered by calcination of the used catalyst at 673 K in air for 5 h followed by reloading with RuO2.

Tetragonal lead tungstate, PbWO4, consisting of a WO4tetrahedron showed high and stable photocatalytic activity for the overall splitting of water, producing a stoichiometric quantity of H2and O2under UV irradiation when loading RuO2on the metal oxide. The activity was found to strongly depend on the preparation temperature of PbWO4. In the temperature range 773-1273 K, a maximum appeared at around 1023 and 973 K when prepared in air and under a N2atmosphere, respectively. X-ray diffraction analysis and SEM observation showed that high activity was achieved with a combination of crystallized PbWO4with a high dispersion of RuO2particles. The DFT calculation for PbWO4with the d10s2-d0electronic configuration showed that the top of the valence band (HOMO) was composed of hybridized O 2p Pb 6s orbitals, while the bottom of the conduction band (LUMO) consisted of hybridized W 5d O 2p Pb 6p orbitals. Considerable dispersion was observed for both the conduction and valence bands, which differed from the small dispersion observed for the photocatalytically inactive CaWO4with a similar crystal structure. Photoexcited electrons and holes with high mobility were considered to be responsible for the high photocatalytic performance of PbWO4. The useful role of a Pb2ion with the d10s2electronic configuration in photocatalysis has been elucidated.

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Oxynitride photocatalysts with d10electronic configuration are presented as effective non-oxide catalysts for overall water splitting. Germanium nitride (β-Ge3N4) having a band gap of 3.8-3.9 eV modified with RuO2nanoparticles as a cocatalyst is shown to achieve stoichiometric decomposition of H2O into H2and O2under UV irradiation (λ > 200 nm). A novel solid solution of GaN and ZnO, (Ga1-xZnx)(N1-xOx), with a band gap of 2.4-2.8 eV (depending on composition) achieves overall water splitting under visible light (λ > 400 nm) when loaded with an appropriate cocatalyst. The narrower band gap of the solid solution is attributed to the bonding between Zn and N atoms at the top of the valence band. The photocatalytic activity of (Ga1-xZnx)(N1-xOx) for overall water splitting is strongly dependent on both the cocatalyst and the crystallinity and composition of the material. The quantum efficiency of (Ga1-xZnx)(N1-xOx) with Rh and Cr mixed-oxide nanoparticles is 2-3 % at 420-440 nm, which is the highest reported efficiency for overall water splitting in the visible-light region.

Risk factors for acquiring hepatitis E among individuals in industrialized countries including Japan are not fully understood. We investigated whether Japanese blood donors with or without an elevated alanine aminotransferase (ALT) level are likely to have hepatitis E virus (HEV) infection. Serum samples were collected from 5,343 voluntary blood donors including 1,087 donors with elevated ALT of 61–966 IU/L and 4,256 donors with normal ALT (≤60 IU/L) at two Japanese Red Cross Blood Centers, and were tested for the presence of anti‐HEV IgG by in‐house enzyme‐linked immunosorbent assay (ELISA). Overall, 200 donors (3.7%) were positive for anti‐HEV IgG, including 32 (2.9%) with elevated ALT and 168 (3.9%) with normal ALT. Serum samples with anti‐HEV IgG were further tested for the presence of anti‐HEV IgM by in‐house ELISA and for HEV RNA by reverse transcription (RT)‐polymerase chain reaction (PCR). Three donors with ALT of 966, 62 or 61 IU/L were positive for anti‐HEV IgM and HEV RNA. The HEV isolates obtained from the three viremic donors segregated into genotype 3, were 91.5–93.4% similar to each other in the 412 nucleotide sequence of open reading frame 2, and had the highest identity of 91.5–94.9% with the JRA1 isolate which was recovered from a Japanese patient with sporadic acute hepatitis E who had never been abroad, suggesting that these three HEV isolates are indigenous to Japan. This study suggests that a small but significant proportion of blood donors in Japan with or without elevated ALT are viremic and are potentially able to cause transfusion‐associated hepatitis E. J. Med. Virol. 73:554–561, 2004. © 2004 Wiley‐Liss, Inc.

Dehalogenation polycondensations of 2,7-dibromo-9,10-dihydrophenanthrene with isolated zero-valent nickel complex and electrochemically generated zero-valent nickel complex afford p-conjugated poly(9,10-dihydrophenanthrene-2,7-diyl). The electrochemically synthesized polymer is obtained as a thin film on electrode, and shows a reversible electrochemically doping-undoping cycle in an oxidation region. The polymer has essentially the same p-conjugation system as that of poly(p-phenylene).

The tide compound was prepared from bis(methylthio)methane as a crystalline compound. The molecular structure was determined by X-ray crystallographic analysis, and reactions with alkyl metals and a Wittig reagent were examined.

Reaction of 2,5-dibromopyrimidine with a zero-valent nickel complex affords poly(pyrimidine-2,5-diyl). This new polymer is easily converted into electrical conducting materials by chemical and electrochemical reductions, the latter reduction occurring at the highest potential (−1.75 V vs. Ag/Ag+) among reported π-conjugated polymers.

Chemical and electrochemical dehalogenation polycondensations of 2,6-dichloroquinoline, 2,6-dibromoquinoxaline, and 2,6-dichloro-1,5-naphthyridine using nickel complexes afford poly(quinoline-2,6-diyl), poly(quinoxaline-2,6-diyl) and poly(1,5-naphthyridine-2,6-diyl), respectively. These polymers take linear structures, and have more extensively delocalized π-conjugation system as well as higher electron-accepting properties than their isomeric poly(quinoline-5,8-diyl) and poly(quinoxaline-5,8-diyl) as revealed by their λmaxpositions and reducing potentials.

Asymmetric Michael and [2+2] cycloaddition reactions between enamines and methyl (E)-4-oxo-4-(2-oxo-1,3-oxazolidin-3-yl)-2-butenoate proceed with a chiral titanium reagent generated in situ from dichlorodiisopropoxytitanium and a tartrate-derived chiral 1,4-diol. In the presence of excess amounts of the chiral titanium reagent, good to moderate enantioselectivity is attained. The reactions are also well catalyzed even with a catalytic amount of the titanium reagent.

Ar+-irradiated a-Si1-x, Cx: H films prepared by magnetron sputtering have been investigated by electron spin resonance (ESR) spectroscopy. ESR signals with g1 g2 and g3 values of 2·0020, 2·0017 and 2·0006 respectively are observed for all films deposited on T-1030 quartz substrates, while the resonance at g = 2 0050 due to the silicon dangling bonds is predominant for those on ES quartz substrates. The appearance of an ESR signal resembling the E' centre in quartz is found to be strongly related to the nature of the substrate. Taking into consideration the fact that the T-1030 substrate contains larger quantities of impurities such as aluminium, boron, iron and copper than the ES substrate, it is concluded that, on Ar +-irradiation, the formation of paramagnetic defects such as the E centre and/or silicon dangling bonds depends on the amount of impurities in the substrate.

New electron spin resonance (ESR) lines with g1 = 2·0017 and g2 and g3 = 2·0006 have been found in the ESR spectra of as-deposited a-Si1-x Cx:H films prepared by magnetron sputtering of silicon in the gas mixtures of methane and argon. Similarities between the observed spectra and those for the E' centre in glassy SiO2 are discussed.

Transparent p-type CuBr1[?] x I x semiconducting thin films with a variable band gap were prepared using spin coating, which is a non-vacuum process. The dependence of their structural and optical properties on the CuBr1[?] x I x composition was investigated. In X-ray diffraction patterns, the dominant CuBr1[?] x I x peak was found to shift to higher angles with decreasing mixing ratio x. The Z1,2 and Z3 exciton absorption bands were observed from 300 to 400 nm, and the absorption wavelength varied with x. The ionization potential was determined using photo yield spectroscopy, and was found to increase with increasing x. These results suggest that the valence band maximum for CuBr1[?] x I x depends on the composition. The results obtained in the present study allowed the energy band structure for this material to be proposed.

Various types of p-block metal oxides and nitrides were employed as catalyst supports for Ru metal in liquid-phase citral hydrogenation. Compounds containing Ga3+ions, in particular GaOOH, were found to exhibit remarkable support effects on the enhancement of catalytic activity and reaction selectivity for the production of a,ß-unsaturated alcohols (nerol and geraniol).

RuO2-loaded hexagonal YInO3consisting of a distorted InO5trigonal bipyramid was found to be photocatalytically active in the water-splitting reaction. The characteristic role of the InO5structure in the photocatalytic performance is described.

In the presence of RuO2, Pb-deficient lead tungstates, PbxWO4(x< 1.0), showed higher photocatalytic activity compared to stoichiometric PbWO4for water decomposition. The highest activity was obtained at x= 0.75 in the range x= 0.2–1.1. The effects of the electronic structures on the photocatalysis are suggested.

Ruthenium oxide-loaded Sr2+-doped CeO2with f0d0electronic configuration was found to have photocatalytic activity for overall water splitting into H2and O2under UV irradiation, whereas neither undoped CeO2nor stoichiometric compounds such as SrCeO3and Sr2CeO4was photocatalytically active.

Divalent-metal-ion (Zn2+or Mg2+)-doped GaN with d10electronic configuration was found to make a high and stable photocatalyst for overall water splitting when combined with RuO2as a promoter, whereas neither undoped nor tetravalent-metal-ion (Si4+or Ge4+)-doped GaN showed photocatalytic activity upon loading of RuO2. The present work clearly demonstrated the marked effects of dopants on photocatalytic performance of the metal nitride GaN for water splitting.

Lead tungstate, PbWO4, with a tetragonal structure was found to make a stable photocatalyst for the decomposition of water to produce H2and O2when combined with RuO2. This is the first example of tungsten oxide that is photocatalytically active for the reaction. The structural feature of PbWO4is the presence of tetrahedral WO4. The DFT calculation showed that Pb2+with d10s2electronic configuration had significant influences on both valence and conduction band structures.

A p-block metal oxide of SrIn2O4with d10configuration was found to be a new photocatalyst for the overall splitting of water when combined with RuO2.

Oxidation of poly(quinoline-2,6-diyl) and its analogue with H2O2gives N-oxidized products, which show dc conductivity of 2.3–3.2 × 10−6S cm−1without doping.

A convenient method for the preparation of a bissilyl ketone is developed via a bissilyl ketone acetal as its percursor. The bissilyl ketone reacts with electron deficient alkynes and alkenes in the presence of Pd(0) catalyst to give bis-silylated products.

A water-repellent silicon (Si) surface with a nanostructure was formed by simple wet chemical etching using catalysis of a silver nanoparticle. Water repellency can be increased by forming micro- or nanostructures on the Si surface. A single nanosized silver particle dispersion solution was coated onto a Si(100) substrate with a polished surface. The samples were soaked in an aqueous etching solution of hydrofluoric acid and hydrogen peroxide. The roughness and depth of the surface structure increased with increasing etching time. The Si surface with the nanostructure had a contact angle of 130°, indicating a water-repellent surface, whereas the surface without the nanostructure had a contact angle of 68°.

In order to control electric field relaxation at the tips of practical emitters, we found that volcano-structured double-gated field emitter arrays (VDG-FEAs) could be improved by placing the focusing electrode 470 nm below the electron extraction electrode. We demonstrated that this approach enables excellent endurance in terms of focusing potential, and confirmed its superior focusing characteristics. Even under strong focusing operation at a focusing electrode voltage of 5 V, this VDG-FEA maintained the anode current of 1.9 µA, which was 5 times larger than that of the VDG-FEA with the same height of the focusing and electron extraction electrodes.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

High-quality Ga1-xInxAs1-ySby/InAs with mirror-smooth surfaces were grown at 650-595°C by means of Liquid Phase Epitaxy (LPE). The compositional and growth temperature dependences of the cutoff wavelength for epilayers were investigated. Van der Pauw measurements, optical microscopy, Fourie Transform IR (FTIR) spectroscopy, Electron Probe Microanalysis (EPMA), Secondary Ion Mass Spectroscopy (SIMS) and Photoluminescence (PL) spectroscopy were used to characterize the quality of epilayers. The results show that the purity of epilayers is considerably improved by doping Gd in the melt. Room-temperature electron mobility up to 30000 cm2/(V·s) with carrier density of 5.7×1015cm-3and full width at halfmaximum (FWHM) of the PL spectra as narrow as 12.45 meV, which are the best results so far for this material to our knowledge, have been achieved. The cutoff wavelengths of epilayers are between 3.4 and 5.0 mm at room temperature.

Surface potential and thermally stimulated currents (TSC) were examined for negatively corona-charged spherulitic polypropylene (PP) which was isothermally crystallized at 140°C for 2 or 4 hours from the 190°C melt of PP. It was found that the surface potential of the 4 hours-crystallized PP containing many large spherulites was limited to below about -900 volts. However, untreated PP and the 2 hours-crystallized spherulitic PP showed no surface potential saturation up to -1800 volts, which is the limit of the charging apparatus used in this study. From the results on the TSC of these samples, their surface potential saturation can be explained in terms of decrease in the number of charge trapping sites which are located in the interspherulitic amorphous regions of these samples. It was also demonstrated that the internal structure of spherulites did not contribute significantly to the charging saturation of spherulitic PP.

Multi-level signals are written and read out in TbFe/SiO compositionally modulated films, which consist of thin amorphous TbFe layers separated by dielectric SiO layers. Writing of four-level signals is performed with four-level magnetic field taking advantage of the fact that the coercive forces of three TbFe layers in the film are different from one to another. The four-level signals are read out through Faraday rotation which depends on the configurations of magnetization of the films. TbFe/SiO compositionally modulated films are potential media for magneto-optical recording with bit density several times as high as current magneto-optical recording disks.

Lateral p-n junctions on GaAs (111)A patterned substrates are characterized through the spatially resolved detection of light emission by current injection using a collection-mode near-field scanning optical microscope. The junctions are one-step grown at the upper and the lower end of the slope, taking advantage of the amphoteric nature of Si in GaAs. Although the width of the transition region determined from spatially resolved photoluminescence measurements is much wider in the lower junction than in the upper one, the broadness of the junction, which is observed for the first time owing to the high resolution of the detection system, is the same for both junctions.

One-step growth of lateral p-n junctions on GaAs patterned substrates is investigated to demonstrate the possibility of obtaining a current confinement structure by utilizing the amphotericity of Si. Rectangular patterns of the (001) plane encircled by four {110} sidewalls were etched on the substrates by means of anisotropic etching of an NH4OH+H2O2+H2O solution with high H2O content. Si-doped GaAs layers are grown on thus-prepared patterned substrates by molecular beam epitaxy. A cathodoluminescence study shows the layers grown on the {110} sidewalls are p-type, whereas they are n-type on the (001) surface. The potential of the lateral p-n junctions for forming a current confinement structure for surface light emitting devices is discussed.

Magnetization (M) and X-ray diffraction patterns of amorphous Gd-Tb-Fe films were measured. The film annealed at 330°C for 3 hours under a pressure of low vacuum (1×10-3Torr?1×10-2Torr) showed X-ray diffraction peaks corresponding to bcc Fe and oxides of rare earth metals, and its Mincreased. We concluded that these results and the irreversible increase of Mat temperatures higher than 200°C are caused by clustering of Fe due to immiscibility of Fe with selectively oxidized rare earth metals. To determine the exact crystallization temperature of amorphous RE-TM films, oxidation of the films must be carefully avoided.

Dependence of anisotropy constants Kuon rare earth atoms in rare earth-transition metal amorphous films was studied. To minimize the influence of the preparation condition on Ku, Gd-R-Co (R=Tb, Dy, Ho, Er) films in which the compositions of R are small were chosen and the magnetic torque was measured. It became clear that even in amorphous films, Kuis mainly determined by the single atomic character of an added rare earth element. This result suggests that the direction of 4felectron clouds may be aligned through a structural anisotropy such as pair-ordering or an anisotropic microstructure.