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The Mo adsorption/99mTc elution properties of alumina used as Mo adsorbents are examined for the development of 99Mo/99mTc generators using 99Mo produced by the (n, γ) method. MoO3 is irradiated by the Kyoto University Research Reactor (KUR). The alumina columns are filled with three types of alumina made from different raw materials. In this paper, elongated tubes are used as columns and the properties under Mo dynamic adsorption conditions on alumina are compared with those under static adsorption conditions. The results obtained suggest that the 99Mo/99mTc ratio specified by the Minimum Requirements for Radiopharmaceuticals of Japan (MRRP) is greatly affected by the method of adsorbing Mo on alumina.

We have performed ultrahigh-resolution angle-resolved photoemission spectroscopy (ARPES) to elucidate the nature of quasiparticle dynamics in graphite. We found fairly sharp quasiparticle peak of π band around K ( H ) point in the vicinity of the Fermi level, together with the strong mass renormalization of the band (kink). The imaginary part of electron self-energy (Im Σ ) shows a sudden drop below 0.18 eV, indicative of a strong electron–phonon coupling. The linear energy dependence of Im Σ at higher binding energies provides an evidence for the deviation from the conventional Fermi liquid theory.

We report high-resolution angle-resolved photoemission spectroscopy (ARPES) on high quality single crystal of graphite (kish graphite) to elucidate the origin of anomalous physical properties of carbon-based materials. We found an almost flat band in the vicinity of the Fermi level around the K(H) point which is not predicted by the bulk band calculation. We discuss the origin of this anomalous structure in relation to the edge-localized state on the step edges of cleaved surface.

High-temperature superconductors (HTS) are the key technology to achieve super-high magnetic field nuclear magnetic resonance (NMR) spectrometers with an operating frequency far beyond 1GHz (23.5T). (RE)Ba

We report ultrahigh-resolution angle-resolved photoemission results on kish graphite. We found an evidence for a sharp quasiparticle peak around K(H) point. Self-energy analysis of quasiparticle lifetime indicates presence of a strong electron–phonon coupling and the linear energy-dependence of scattering rate which shows marked deviation from the conventional Fermi-liquid theory.

The microstructure of Ag-sheathed (Bi,Pb) 2 Sr 2 Ca 2 Cu 3 O x tapes is quantitatively investigated by transmission electron microscopy and electron probe microanalysis. Volume fraction of the second phases decreases as the critical current density of the wire increases. The relationship between the microstructure and the critical current density is discussed.

A new class of potassium-oxygen-graphite intercalation compounds, KO x -GICs ( C 4 n KO x , stage number n = 1, 2; x ~ 2), having the quadruple atomic layers intercalate of KOOK is characterized by X-ray diffraction, magnetic susceptibility and electrical conductivity. In-plane CC distances are elongated by 0.009 and 0.0044 A by the introduction of the intercalate for 1st and 2nd stage compounds, respectively, which correspond to the Fermi energy E F = 2.1 and 1.5 eV and prove the partial valence state of oxygen, O −δ ( δ ~ 0.34). The density of states at E F obtained from the Pauli paramagnetic susceptibility is about three to six times larger than that of the graphitic π-band, which reveals the participation of the intercalate bands in the electronic structure around E F . Taking into account the small anisotropy of electrical conductivity (250), the KO x intercalate has a weakly delocalized electronic nature.

The C6o crystals which are exposed to light in oxygen show a ferromagnetic magnetization with a small hysteresis of the coercive field Hc = 10-2 T and a saturation magnetic moment (Ms) of 10-3 I.LB per Go. The most striking feature is that Ms remains up to Tc = 800 K, an extraordinarily high critical temperature. The small Ms indicates that only a small part of the sample contributes to the ferromagnetism, but the ferromagnetic part can be enriched by dissolution of pure c60 into toluene; a residue substance has a larger Ms of 10-1 pUc60. The x-ray powder diffraction and the Raman scattering measurements reveal that the residue has a crystal structure close to pure C6o crystal although a broadening of line width in the diffraction spectrum and a small shift of Ag and Hg vibrational modes to a lower energy are observed. The mechanism of the ferromagnetism will be discussed in relation to oxidization and polymerization of C6o molecules.

X-ray diffraction and magnetic susceptibility measurements have been made for graphite nanotubes and encapsulation compounds of TaC and CeC2;. In the nanotubes the graphite layers expand 2.27% (C0 = 6.852 A) in the interlayer spacing, and only 0.09% in the in-plane direction. The observed (hk0) diffraction peaks show a pronounced asymmetric lineshape of the Warren type, which results from complete stacking disorder. The carbide inside the nanotube, which is a single crystal in most cases, has a lattice parameter very close to that of the carbide in the bulk, indicating no significant effect due to encapsulation. The superconducting Tc of encapsulated TaC is very close to that of the bulk sample. An antiferromagnetic transition has been observed in the CeC2 encapsulation compound; the observed TN is consistent with that found in an earlier neutron study of a bulk sample.

We present a high-resolution synchrotron X-ray diffraction study of xenon adsorbed on single-crystal graphite for coverages of two, three and six monolayers. We observe the evolution of the lattice mismatch between the xenon overlayer and a square root 3* square root 3R30 degrees structure commensurate with the underlying substrate. In the case of the bilayer we see a first-order incommensurate-commensurate (IC-C) phase transition at 62.0 K+or-1.2 K, which we demonstrate is consistent with the layer closest to the substrate having locked into the commensurate sites. The role of substrate quality is discussed and we conclude that previous studies on relatively poorer substrates may have favoured equilibrium structures strongly influenced by the surface imperfections. The risk of an insufficiently equilibrated adsorbate is discussed in the context of the very slow kinetics we observe for multilayer xenon on high-quality substrates. For the three- and six-layer adsorbates we observe a systematic increase in lattice mismatch with film thickness and no indication of an incommensurate-commensurate transition. We conclude that the trilayer system consists of many distinct domains approximately 500 AA across, each of which has a random close packed structure.

Magnetic properties of Cs x C60 have been studies by the magnetic susceptibility and ESR. The observation of Pauli and Curie-Weiss susceptibilities implies the existence of a metallic phase Cs1C60 and a paramagnetic phase Cs4C60.

We have performed ultrahigh-resolution angle-resolved photoemission spectroscopy on high-quality single crystals of graphite to elucidate the character of low-energy excitations. We found evidence for a well-defined quasiparticle (QP) peak in the close vicinity of the Fermi level comparable to the nodal QP in high-T(c) cuprates, together with the mass renormalization of the band at an extremely narrow momentum region around the K(H) point. Analysis of the QP lifetime demonstrates the presence of strong electron-phonon coupling and linear energy dependence of the QP scattering rate indicative of a marked deviation from the conventional Fermi-liquid theory.

Diagnostics in infrared and far-infrared range for Heliotron E are described; (a) FIR interferometer for measuring electron density profile and (b) ECE for electron temperature profile as routine work, and (c) Fraunhofer diffraction method with a CO/sub 2/ laser for density fluctuation and (d) Thomson scattering with a D/sub z/O laser (/spl lambda/ = 385 /spl mu/m) for Ion temperature, as new methods.

The N[sub 2] adsorption isotherm of C[sub 60] crystals at 77 K was determined. The N[sub 2] adsorption isotherm was of type I, which indicates the presence of micropores. The observed micropore volume, total surface area, and external surface area were 0.014 mL g[sup [minus]1], 24 m[sup 2] g[sup [minus]1], and 1 m[sup 2] g[sup [minus]1], respectively. O[sub 2] molecules were reversibly adsorbed even above the boiling point. The amount of O[sub 2] adsorbed at 100 kPa and 303 K corresponded to an O[sub 2] molecule per two C[sub 60] molecules. The defect-associated micropore model was proposed on the basis of the estimated defect concentration and the critical percolation value. 28 refs., 3 figs.

The frequency and the antibacterial sensitivity of Streptococcus pneumoniae strains isolated from 6 key hospitals (in 5 areas) and 1 otorhinolaryngology clinic in Gifu Prefecture from February to March, 1999, were investigated with several antibiotics. A total of 128 strains of Streptococcus pneumoniae were isolated throughout the study: 47 strains (36.7%) of penicillin-susceptible S. pneumoniae (PSSP), 51 strains (39.8%) of penicillin-intermediate S. pneumoniae (PISP), and 30 strains (23.4%) of penicillin-resistant S. pneumoniae (PRSP); the resistant bacteria being relatively prominent. In these hospitals, PSSP was isolated by 38.8% in all the key hospitals and by 30% in the otolaryngology clinic with almost no discernible difference. PISP was isolated by 63.3%, higher in the otolaryngology clinic and PRSP by 28.6%, higher in the key hospitals conversely. The MIC90s in PISP and PRSP were determined with the antibiotics. In result, only cefditoren (CDTR) showed favorable antibacterial activities with the MIC90 of 0.78 microgram/ml among penicillins or oral cephems. The MIC90s of carbapenems such as imipenem (IPM), meropenem (MEPM), and panipenem (PAPM) were less than 0.39 microgram/ml; particularly, PAPM showed the highest antibacterial activities. Among new quinolones such as tosufloxacin (TFLX), levofloxacin (LVFX), sparfloxacin (SPFX), and ciprofloxacin (CPFX), TFLX showed the highest antibacterial activities with the MIC90 of 0.39 microgram/ml. Other agents showed very low antibacterial activities as the MIC90s were 25 micrograms/ml in minocycline (MINO) and more than 100 micrograms/ml in clarithromycin (CAM) and clindamycin (CLDM).

Crystal structure and magnetic properties of EuxSr6−xC60 were studied. Ferromagnetic transition was observed at 10–14 K, and magnetic moment is ascribed to Eu2+. The divalent state of Eu is also confirmed by Eu LIII-edge XANES experiments. The fact that ferromagnetic transition is observed even at a dilute case (x=1) suggests the magnetic interaction is caused through C60 molecules, that is, π-f interaction, rather than direct exchange interaction between Eu atoms.

Pervaporation and gas permeation properties of microporous silica membranes made by a sol−gel method are discussed. Defect free molecular sieving membranes are prepared by a dip coating process. The molecular sieving performance was measured and controlled based on gas permeation behavior of the membranes. The apparent activation energy for helium permeation and He/N2 perm-selectivity values were used as the parameters for optimization of the membrane performance. The membranes with very high activation energy for He diffusion were used for pervaporation studies with a methanol/MTBE mixture at 323 K. Separation factor values as high as 260 were measured at a total liquid flux of 0.3 kg/m2 hr. Sorption studies performed on corresponding silica gels revealed a separation mechanism based on diffusion of vapor molecules. Permeation of the vapor molecules through the micropores followed an activated diffusion mechanism. The gas permeation data could provide an understanding of the pore size distribution of the membrane, and the vapor sorption and diffusion data on the size and connectivity of the membrane pores.

To determine prevalence of gastric spiral organisms (GSO) in dogs and cats that were clinically normal or had primary gastrointestinal disease and to compare histologic lesions of the stomach in dogs and cats with and without GSO.21 dogs and 10 cats that were clinically normal and 56 dogs and 33 cats with gastrointestinal disease.Case-control study.Unevenness of the gastric mucosal surface was detected, using endoscopic techniques in 20 and 25% of clinically normal and abnormal dogs, respectively. On histologic examination, GSO were located on the mucosal surface within or beneath the mucus, in gastric pits, and within glandular lumina in 86 and 90% of clinically normal dogs and cats, respectively, and in 61 and 64% of clinically abnormal dogs and cats, respectively. Prevalence of GSO infection in dogs and cats that were clinically abnormal was not higher than in those that were clinically normal. Infection was detected in stomachs of60% of dogs and cats 1 year old or less. Helicobacter pylori was not isolated from any specimen; however, specimens in which GSO were found had positive results on a urease test.Prevalence of GSO infection was high in clinically normal and abnormal dogs and cats, some of which were young. This should be considered during assessment of clinically normal animals with GSO as they can be a potential reservoir for infection in human beings.

The effect of EEG-driven photic stimulation on stress-related endocrine function was studied. Subjects were 16 healthy males divided into a photic stimulation group (n = 8) and a control group (n = 8). Electrodermal and emotional lability measures were assessed by nonspecific skin conductance response and the Maudsley Personality Inventory, respectively. Plasma cortisol and beta-endorphin concentrations were measured both before and after EEG-driven photic stimulation as well as the resting condition. Subjects with electrodermal, emotional, or both lability showed comparable decreases of plasma beta-endorphin on photic stimulation as did the stable subjects. Under resting control conditions, however, they showed significant increases of beta-endorphin compared to both stable subjects as well as the photic stimulation condition. In addition, labile subjects showed significant alpha enhancement on photic stimulation compared to stable subjects and to the resting control condition. The data suggest that increases of plasma beta-endorphin in labile control subjects may denote a stress response to the conditions of these experiments, and that any decrease by EEG-driven photic stimulation may indicate a reduction of responsiveness to an acute stress.

OBJECTIVE--To compare histologic lesions in the stomach and duodenum of dogs and cats with and without lymphocytic-plasmacytic enteritis (LPE). DESIGN--Case-control study. ANIMALS--20 clinically normal dogs, 40 dogs with LPE, 10 clinically normal cats, and 20 cats with LPE. RESULTS--Unevenness of the mucosal surface was detected in the stomach of 4 of the 20 (20%) clinically normal dogs and 10 of the 40 (25%) dogs with LPE. Mucosal friability was detected in the duodenum of 16 (40%) of the dogs with LPE and 10 of the 20 (50%) cats with LPE. Histologically, clinically normal dogs and dogs with LPE had various degrees of fibrosis in the gastric lamina propria. All of the clinically normal cats and the cats with LPE had slight gastric fibrosis. Clinically normal cats had infiltrates of inflammatory cells similar to those seen in the clinically normal dogs. Significantly more plasma cells and lymphocytes were seen in the duodenal lamina propria of dogs and cats with LPE than in the duodenal lamina propria of clinically normal animals. CLINICAL IMPLICATIONS--LPE should be diagnosed by counting the number of inflammatory cells in the duodenal lamina propria and then comparing that number with the number seen in clinically normal animals.

Panic episodes were described as a distinct form of anxiety by Freud almost 100 years ago, and the recent publication of the Diagnostic and Statistical Manual of Mental Disorders, third edition (D.S.M.-III), has provided the basis for the separate diagnostic entity of panic disorder. In this study, we showed the historical review of research and the result of our clinical study of panic disorder in 7 patients. The following results were obtained: 1) Abnormal DSTs were observed in only two of 5 patients. 2) Five of 6 patients showed high concentration of adrenaline and noradrenaline in urine. 3) Anxiety was provoked by caffeine in two of 5 patients. 4) Depression of T-wave was shown in three of 5 patients with orthostatic E.C.G. 5) Sinus tachycardia was gained in one of 3 patients with Holter E.C.G. 6) Abnormal respiratory functions were observed in all two patients with Treadmill. 7) Only one small heart was observed on a chest radiograph. 8) Panic attacks were provoked by sodium lactate infusion in four of 7 patients.

The grain boundary phase of silicon nitride containing additives Y2O3 and Nd2O3 has been studied by means of a newly developed 300kV field emission ATEM. The composition of the two-grain boundary phase of about 1 nm thick is successfully determined. It is then found that the compositions among the grain boundaries are not the same and the additives of Y2O3-Nd2O3 are poor in the two-grain boundary, while they are rich in the triple points.

A glycosylphosphatidylinositol (GPI)-anchored protein, 5'-nucleotidase [EC 3.1.3.5], was released from the membrane of bovine liver by use of phosphatidylinositol-specific phospholipase C (PI-PLC) of Bacillus thuringiensis and purified by several column chromatographies to a homogeneous state. The purified protein has an apparent molecular mass of 61 kDa, as estimated by SDS-polyacrylamide gel electrophoresis. From the partial amino acid sequence of a tryptic peptide, mixed oligonucleotides were synthesized and used to screen a lambda gt11 liver cDNA library, and one positive clone, pE1, was isolated. Since the insert of the clone lacked the NH2-terminal coding region, another lambda gt11 liver cDNA library was screened by using a synthetic probe corresponding to the 5' region of the insert of pE1. Three additional cDNA clones were obtained. Sequencing of these cDNAs revealed an open reading frame that encodes a 574-residue polypeptide with a calculated mass of 63,084 Da. The predicted structure showed two highly hydrophobic stretches at both ends of the protein, like those of rat and human 5'-nucleotidases. The NH2-terminal 26 residues comprise a signal peptide and the COOH-terminal hydrophobic stretch may serve as a signal for the posttranslational GPI modification. An expression vector of the cDNA, pSVNT, was constructed in a mammalian expression vector pSVL and the 5'-nucleotidase activity was transiently expressed in COS-1 cells. The expressed activity was about 8 times higher than the pSVL-transfected control activity. PI-PLC released 45% of the transiently expressed 5'-nucleotidase activity, indicating that the cDNA isolated here encodes this enzyme expressed as a GPI-anchored protein.

The specific heat of the first-stage graphite intercalation compound C 6 Eu has been studied with the use of a.c. calorimetry. The specific heat anomaly associated with the magnetic phase transition has been observed at T N = 40.0 ± 1.0 K. Another weak anomaly was observed a few degrees below T N , and this is discussed in relation to the metamagnetic phase transitions of the compound.

We have observed high resolution 13C NMR spectra in k-intercalated stages 2, 3, 4 and 6 HOPG compounds. The sample was a block itself or sliced one of HOPG. From T1T of each resolved line we obtained a distribution of density of states N(EF) at the Fermi level among the graphite layers.

An ordered state with a complex magnetic structure has been observed below 4CK. The magnetization for H ⊥ c (c; the c-axis) shows a field-induced phase transition from a small magnetic moment state ( ∼ 0.6μ B ) at lower fields to a larger moment one ( 2.2 - 2.5μ B ) above 25kG. The transition field depends on temperature and is found to be 5 - 2kG. The magnetization for H//c has only a sublinear field dependence. Above 40K the magnetic susceptibility obeys the Curie-Weiss law with θ = +1.3K and the molar Curie constant C m = 6.78, which suggests that Eu ion is divalent in C 6 Eu.