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We explore the possibility that Te isotopic anomalies measured in Ca-Al-rich inclusions (Fehr et al. 2009) and in leachates of carbonaceous chondrites (Fehr et al. 2006) may be due to mass-independent effects controlled by nuclear field shift rather than to nucleosynthetic processes. Fehr et al.s spectrum of mass-independent anomalies of Te isotopes shows a smooth correlation with mass number and nuclear charge distribution. Ratios of even to odd isotopes, as the 125Te/126Te ratio used by these authors for normalization are particularly prone to nuclear field shift effects. We show that the alternative normalization of isotopic ratios to 130Te/126Te strongly reduces the trend of isotopic fractionation with mass number, leaving only 125Te as truly anomalous. For both normalizations (125Te/126Te and 130Te/126Te), Fehr et al.s results fit the theory of Bigeleisen (1996), which suggests that the nuclear field shift effect can potentially account for the observed Te isotope abundances, as an alternative to nucleosynthetic processes. We propose that these mass-independent effects may be acquired during accretion of sulfides from the solar nebula.

We report the isotope fractionation of zinc (Zn) associated with a redox reaction between Zn(0) and Zn(II). Zn isotopes were found fractionated in pyrometallurgical biphase extraction between liquid zinc and molten chloride. The isotopic composition of Zn in the molten chloride phase was analyzed by multiple collector inductively coupled plasma mass spectrometry and reported as (m)Zn/64Zn (m = 66, 67, and 68) ratios. The observed isotope fractionation consists of the mass-dependent and mass-independent isotope effects. The contributions of the nuclear mass and the nuclear volume to the overall isotope effect were evaluated by employing first-principles quantum calculations and using reported isotope shifts in atomic spectra. The magnitude of the mass-dependent isotope effect was explained by the sum of the isotope effect via intramolecular vibrations and the correction to the Born-Oppenheimer electronic energy. The mass-independent isotope effect was correlated with the Gibbs free energy change in the redox reaction.

Mass-independent isotope fractionations found in laboratory-scale chemical exchange experiments are reviewed. The classic theory of stable isotope fractionation in chemical exchange reactions has been established by Bigeleisen, Mayer, and Urey in 1947. In 1996, the conventional mass-dependent theory was expanded by Bigeleisen to include a mass-independent term named the nuclear field shift effect. The nuclear field shift is an isotope shift in orbital electrons, which results from the isotopic difference in nuclear size and shape. Since the revised theory was proposed, the mass-independent isotope fractionation of various elements, (e.g., Ti, Cr, Zn, Sr, Mo, Ru, Cd, Sn, Te, Ba, Nd, Sm, Gd, Yb, and U), found in chemical exchange systems has been successfully explained as the nuclear field shift effect. In this review article, from both theoretical and experimental viewpoints, origins of mass-independent isotope effects are discussed.

Cadmium isotopes were fractionated by the liquid–liquid extraction technique with a crown ether, dicyclohexano-18-crown-6. The isotopic ratios of m Cd/ 111 Cd (m: 110, 112, 113, 114, and 116) were measured precisely by the multi-collector inductively coupled plasma spectrometry (MC-ICP-MS). When the isotope enrichment factors were calculated, the odd atomic mass isotopes ( 111 Cd and 113 Cd) showed excesses of enrichment comparing to the even atomic mass isotopes ( 110 Cd, 112 Cd, 114 Cd and 116 Cd). This odd–even staggering property originates from the nuclear field shift effect. The contribution of the nuclear field shift effect to the observed isotope enrichment factor was estimated to be 5 to 30%.

In order to enhance the understanding of redox reactions of plutonium ions in molten NaCl-CsCl eutectic, absorption spectrophotometry was performed for Pu3+, Pu4+, and PuO2 2+ in molten NaCl-CsCl at 923 K by controlling the flow-rate ratio of Cl2 and Ar or O2 in the ventilating mixture gas. Based upon the relations of the measured rest potentials to the concentration ratios of [Pu4+]/[Pu3+] and [PuO2 2+]/[Pu4+], the redox potentials of Pu4+/Pu3+ and PuO2 2+/Pu4+ couples in molten NaCl-CsCl eutectic at 923 K were estimated.

Slightly overstoichiometric lithium orthosilicate pebbles are fabricated from lithium hydroxide and silica by a melting and spraying method in a semi-industrial scale facility. The authors performed out-of-pile annealing tests using the lithium orthosilicate pebbles irradiated in a research reactor. Moreover, the effect of the deposition of palladium in the lithium orthosilicate pebbles on the behavior of tritium release was investigated. The lithium orthosilicate pebbles were irradiated in a research reactor. In the out-of-pile annealing experiments, the temperature of lithium orthosilicate pebbles was raised from ambient temperature to 1173 K at a constant rate of 5 K/min under the stream of 0.1% hydrogen/nitrogen sweep gas. The experimental results indicate that almost all tritium was released as tritiated water vapor from the virgin lithium orthosilicate pebbles. It was also found that a lager amount of tritium was released as the molecular form (HT) from the lithium orthosilicate pebbles deposited with palladium.

The effects of magnetic field on the shape evolution of ferromagnetic fcc Fe–Co particles in Cu–0.83 at.% Fe–1.37 at.% Co alloy single crystals were examined using magnetic anisotropy measurements. The Cu–Fe–Co single crystals were aged at 993 K for 2 h to 24 h under a magnetic field of 10 T parallel to either the [001] or [011] direction. The magnetic anisotropy was examined by measuring magnetic torque around the (100) plane. It was found that the fcc Fe–Co particles are elongated in the direction parallel to the magnetic field. Furthermore, the elongation along [001] is more remarkable than that along [011]. The results are explained quantitatively by considering the minimization of the sum of the interface energy, elastic strain energy and magnetostatic energy of spheroidal particles.

With the introduction of 6-year pharmacy educational program in 2006,a provision was made to assign pharmacist faculties having working experience as pharmacists in pharmacy schools.In October 2007,we conducted a survey to investigate the situation of pharmacist faculties.We sent a questionnaire to 247 pharmacist faculties in 66 pharmacy schools and the response rate was 84.9%.The faculties consisted of professors (43%),associate professors (23%) and lecturers (23%),and 77% of them had a Ph.D.degree.In a typical week,the major activities they engaged in were educational activities (20.6 hrs),research (12.2 hrs) and management (9.6 hrs).While the average time they were occupied by clinical practice was 3.5 hrs,67% of them did not do any.Half of the faculties did not conduct any research with students or graduate students in their own schools,and in 2007 only 55% applied for Grant-in-aid for Scientific Research from the Ministry of Education,Culture,Sports,Science and Technology of Japan.Twenty-six percent said they were very satisfied or satisfied with their work on a five-point scale,and 44% rated their degree of satisfaction as fair.In conclusion,our survey showed that most pharmacy faculties are not sufficiently engaged in clinical practice and do not spend much time in clinical research.We hope that its results will promote discussions among pharmacy personnel concerning the role of pharmacist faculties so that even better clinical pharmacy education may be provided to students in pharmacy schools.

Cyclic deformation behavior of ultra-fine grained (UFG) Cu of 99.99% purity processed by equal-channel angular pressing was investigated. In tension-compression fatigue tests under strain control, UFG Cu showed cyclic softening. Shear bands were formed along the direction inclined by about 45° from the loading axis. Observations using an electron backscattering diffraction technique and transmission electron microscopy revealed that local grain growth took place in the shear bands and overall grains elongated along the shear direction. Cyclic softening can be understood as a result of dynamic grain coarsening occurred intensively in the strain localized shear bands.

Basic electrochemical and spectroscopic properties of Cr3+, Cr2+, Fe3+, and Fe2+ were studied to analyze the cyclic redox reactions of Cr and Fe, which may decrease the current efficiency of the electro-winning method using NaCl–2CsCl melts. The formal redox potentials of the $$ {\text{Cr}}^{3 + } |{\text{Cr}}^{2 + } $$ and $$ {\text{Fe}}^{3 + } |{\text{Fe}}^{2 + } $$ couples, $$ E_{{{\text{Cr}}^{{ 3 + }} | {\text{Cr}}^{{ 2 + }} }}^{\circ \prime } $$ and $$ E_{{{\text{Fe}}^{ 3+ } | {\text{Fe}}^{ 2+ } }}^{\circ \prime } $$ , in NaCl–2CsCl melts at 923 K were spectroelectrochemically determined to be −0.648 ± 0.005 V and $$-0.140 \pm 0.010\,{\text{V}}\,{\text{vs}} .\,{\text{Cl}}_{2}|{\text{Cl}}^{-} $$ , respectively. These values were determined by measuring electromotive force and UV–VIS absorption spectra at varying concentration ratios of trivalent and divalent ions. Cyclic voltammetry was also carried out to examine the characteristics of the voltammograms for the $$ {\text{Cr}}^{3 + } |{\text{Cr}}^{2 + } $$ and $$ {\text{Fe}}^{3 + } |{\text{Fe}}^{2 + } $$ couples in NaCl–2CsCl melts. The $$ E_{{{\text{Cr}}^{3 + } |{\text{Cr}}^{2 + } }}^{\circ \prime } $$ determined by the spectroelectrochemical method was close to that determined by cyclic voltammetry $$ ( - 0.651 \pm 0.006\,{\text{V}}\,{\text{vs}} .\,{\text{Cl}}_{2} |{\text{Cl}}^{-} ) $$ . The effect of temperature on the $$ E_{{{\text{Cr}}^{3 + } |{\text{Cr}}^{2 + } }}^{\circ \prime } $$ in NaCl–2CsCl melts was studied by cyclic voltammetry in the range from 823 to 1,023 K $$ (E_{{{\text{Cr}}^{3 + } |{\text{Cr}}^{2 + } }}^{\circ \prime } = 0.00143T-1.971 \pm 0.005\,{\text{V}}\,{\text{vs}} .\,{\text{Cl}}_{2} |{\text{Cl}}^{-} ) $$ . Diffusion coefficients of Cr3+ and Cr2+, $$ D_{{{\text{Cr}}^{ 3+ } }}^{{}} $$ and $$ D_{{{\text{Cr}}^{ 2+ } }}^{{}} $$ , were determined between 823 and 1,023 K to be $$ D_{{{\text{Cr}}^{3 + } }} = 2.23 \times 10^{ - 3} \,{ \exp }( - 4,\!135/T) $$ and $$ D_{{{\text{Cr}}^{2 + } }} = 3.34 \times 10^{ - 3} \,{ \exp }( - 4,\!106/T) $$ , respectively. Molar absorptivities of Cr3+ and Cr2+ in NaCl–2CsCl melts at 923 K were determined to be 77.8 ± 2.4 M−1 cm−1 at 17,670 cm−1 and 48.0 ± 1.4 M−1 cm−1 at 9,170 cm−1, respectively. In addition, the effects of these ions on the cyclic redox reaction of the pyro-reprocessing process were discussed.

The hydrolysis constants of Th(IV) were determined using the solvent extraction method in a NaClO4solution atI=0.1 and 25 °C. A trace amount of thorium below the solubility limit was used in order to avoid the formation of polynuclear species and colloids in the experiment. The values were compared with the literature data. Considering the effect of competitive hydrolysis reactions under weak acid conditions, the complexation constants of Th(IV) with a series of dicarboxylic acids containing different alkyl chain lengths were determined.

Isotope fractionation of strontium in a solid-liquid equilibrium (at room temperature) was investigated, in which possible species in the liquid phase and solid phase are assumed to be Sr(H2O)82+ and SrO2, respectively. Isotopic analysis was performed by the multi-collector thermal ionization spectrometry (MC-TIMS). Isotope enrichment factor e86,m was observed to be, 0.35 ± 0.20‱(m = 84), 0.00 ± 0.04‱(m = 87), or −0.61 ± 0.23‱(m = 88). Reduced partition function ratios due to intermolecular vibrational frequency shifts were estimated by a quantum mechanics simulation. The estimated e86,84 and e86,88 showed similar values with those experimentally obtained, while calculated e86,87 disagreed with the experimental result. These results suggest an existence of mass-independent isotope fractionation which may be due to the nuclear field shift.

This work reports on chemical isotopic fractionation of Te in a liquid-liquid extraction system using a crown ether of dicyclohexano-18-crown-6. Te isotopic composition was measured by multi-collector inductively coupled plasma spectrometer. We demonstrated the existence of a 125Te anomaly in two experiments at different molarities of HCl. The results of the present experiments fit the nuclear field shift theory of Bigeleisen. We finally showed the importance of the isotope of normalization in the representation of the mass-independent term.

Chromium isotopes were fractionated in a liquid-liquid extraction system using dycycrohexano-18-crown-6 at various hydrochloric acid concentrations. The isotopic ratios of 50Cr/52Cr and 53Cr/52Cr were measured precisely by the multi-collector inductively coupled plasma spectrometry (MC-ICP-MS). The isotope enrichment factor for 50Cr-52Cr isotope pair was shown to vary between 1.5~2.3% and changed as a function of acidity. The magnitudes of mass-independent isotope fractionation could be attributed to the nuclear field shift effect.

Strontium isotopic ratios in a natural matrix reference material (IAEA-A-12) containing strontium-90 were measured by means of a thermal ionization mass spectrometer with a multi-collector system (MC-TIMS). There was significant difference in the measured isotopic ratios between the IAEA-A-12 and a standard reference material of the strontium isotopes (SRM 987), and 88Sr/86Sr and 87Sr/86Sr of the IAEA-A-12 were smaller and 84Sr/86Sr was larger than those of the SRM 987. 90Sr/86Sr ratio was estimated, by calculating the number of atoms of the strontium-90 from its activity, to be 3.55 × 10−10.

A dislocation bow-out model has been developed to explain the strength of ultra-fine grained (UFG) materials with grain size roughly between 20 nm to 500 nm. In the model, perfect dislocations are assumed to be nucleated at grain-boundary sources and bow out between two pinning points on a boundary. Yielding is considered to occur when a dislocation takes a semi-circular shape under applied stress. Statistical consideration is introduced to evaluate the most probable pinning-point distance as a function of grain size. Comparison with experimental results is made for fcc UFG metals. It is found that yield stress as well as thermal activation parameters can be explained reasonably by the present theoretical model.

Out-of-pile tritium release experiments were performed using slightly overstoichiometric lithium orthosilicate pebbles irradiated in a research reactor. In the experiments, various sweep gases such as pure nitrogen gas, hydrogen/nitrogen gas and water vapor/nitrogen gas are used to investigate the effect of difference in sweep gas composition on tritium release form the breeder material. The experimental results indicate that almost all tritium was released as tritiated water vapor regardless of difference in gas composition of the sweep gas. Most of the chemical form of tritium released was tritiated water vapor even when the hydrogen/nitrogen gas was used for the sweep gas. It was also found that a considerably smaller amount of tritium was released when a pure nitrogen gas was used as the sweep gas. Comparison of the experimental results reveals that the tritium release rate is substantially enhanced if the sweep gas contains water vapor.

A new severe plastic deformation (SPD) process to obtain nanocrystalline (NC) structure by wear is reported. An Al–Al 3 Ti functionally graded material fabricated by a centrifugal method is wear tested to investigate the microstructure of the wear-induced layer. When the sliding distance of the wear exceeds l = 100 m, the wear-induced layer is obtained just below the worn surface. The microstructure of the wear-induced layer consists of fine Al 3 Ti fibrous particles and an NC solid-solution matrix containing a partly amorphized phase. The NC matrix has fine grains with a mean diameter of 16 nm and is a supersaturated solid-solution in which Ti is dissolved in the Al matrix. From the microstructure, it is estimated that the wear-induced layer is formed at a nominal shear strain of more than 90 and an effective shear strain of more than 52. An NC structured wear-induced layer is generated by the SPD process.

This paper presents a newly developed an 80MVA GCT STATCOM for the Kanzaki substation of the Kansai Electric Power Co., Inc. The commercial operation was started in June, 2004. The main purpose of the STATCOM is to maintain voltage during single circuit connection of source to the substation resulting from an AC system fault in order not to break down load system of the substation. The developed STATCOM has three distinctive features: (1) a high-efficient, compact and AC filter-less system using multistage three-level GCT converter and customized harmonics reduction PWM; (2) a coordinated voltage regulator with tap control of main transformers; and (3) a continuous operation from a single phase-ground fault through reclosing of the faulted circuit by limiter adjustments of the reactive current reference. This paper describes characteristics of the coordinated voltage control in the substation, and shows performance of the continuous operation during AC system faults using data of commercial operations and the simulation results.

Chromium isotopes were fractionated by continuous extraction using dicyclohexano‐18‐crown‐6 as an extractant. This system was designed for accumulating isotope effect into the aqueous phase. After a long period of operation (∼2 weeks), the Cr isotope ratios in the residual aqueous phase were precisely measured by using a multi‐collector thermal ionization mass spectrometer with the total evaporation technique. The analytical results showed a clear mass‐independent isotope fractionation. The mass‐independent property was consistent with that obtained from a batch extraction. The isotopic mass balance was verified to be preserved in the continuous extraction. The Bigeleisen's 1996 theory gave the consistent explanation on the Cr isotope effect, in which the mass‐independent isotope effect was identified to be the nuclear field shift effect.

Electronic absorption spectra of trivalent praseodymium in various alkali chloride melts were precisely measured. The oscillator strength of the hypersensitive transition, 3F2 ←3H4, showed a clear decrease with increasing temperature. This temperature dependence was the inverse of reported cases for other trivalent lanthanoides. The Judd-Ofelt parameter was analysed, and the calculated oscillator strength showed quite good agreement with the experimentally obtained oscillator strength. However, the Ω2 parameter, which is sensitive to the ligand environment change, showed a clear decrease with increasing temperature and negative values at high temperature. We found that the 3P0 ←3H4 transition and its shoulder peak are quite sensitive to the coordination circumstance change of the [PrCl6]3− complex in molten chlorides. These intensities could be correlated with the octahedral symmetry of [PrCl6]3−.

Electronic absorption spectra of trivalent neodymium in LiCl–KCl eutectic, NaCl–2CsCl eutectic, CaCl2, LiCl, CsCl and mixtures of these at various temperatures were measured, and the variation of the absorption bands, 4G5/2, 2G7/2 ← 4I9/2, were carefully analyzed. The dependence of their molar absorptivity, oscillator strength, and the degree of the energy splitting on temperature and melt composition were determined. As a result, it was suggested that the NdCl63− complex keeps its octahedral symmetry in the NaCl–2CsCl eutectic, while this symmetry is more distorted in LiCl and CaCl2. Based on these data, the chemical status of NdCl63− complex in molten chlorides was discussed.

A flying qubit is proposed that uses an elementary excitation in superconducting nanocircuits including Josephson transmission lines. Our proposed qubit can resolve an existing qubit-manipulation problem that is unavoidable in solid-state based quantum computers, and has the potential for integrating computation and communication using its flying nature. A concrete example is provided of quantum logic gates using our proposed qubit.

The dependence of precipitate shape on the elastic strain energy caused by anisotropy of the elastic moduli is discussed for polyhedral precipitates with purely dilatational misfit strains. By considering cubic structures for the precipitates and matrix phase, the elastic strain energy is calculated for the precipitate shapes of a {1 0 0} cube, a {1 1 0} rhombic-dodecahedron, a {1 1 1} octahedron, and the truncated shapes of all three polyhedra. The anisotropy of the elastic moduli of Cu is used for the numerical calculations. The polyhedral shapes of the {1 1 1} octahedron and {1 0 0} cube result in the highest and lowest values of the elastic strain energy per unit volume of precipitate. The calculated values of the elastic strain energy obtained for the truncated polyhedra are compared with values estimated using a geometrical method that considers the area changes of the {1 0 0}, {1 1 0} and {1 1 1} interfaces.

The extraction behavior of antimony into a transuranic element extraction (TRUEX) solvent containing octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide was investigated. An extraction study with a PUREX solvent was also performed for comparison. Adding oxalic acid into the TRUEX system was quite effective for decreasing the distribution ratio to ≈1=4. In order to clarify possible antimony species in a nitric acid medium, the solubility measurement of antimony oxide was performed. The extraction results and solubility data suggested that the monovalent cationic antimonyl would be extracted into the TRUEX solvent.

The thermal-neutron capture cross section (σ0;g) and the resonance integral (I 0,g) leading to the ground state of 242Am were measured by an activation method for neutron capture by241 Am. A method with gadolinium, which was similar to the cadmium difference method, was used to measure the cross section σ0;g with attention to resonances of241 Am. Americium chloride samples containing241 Am radioisotope were irradiated for 68 h in the long-irradiation plug of the Kyoto University Research Reactor, KUR. Wires of Co/Al and Au/Al alloys were used as monitors to determine thermal-neutron fluxes and epithermal Westcott's indexes at the irradiation positions. An α-ray spectrometer was used to measure the activity ratios of242 Cm to241 Am. On the basis of Westcott's convention, the σ0;g and I 0,g values were determined as 628 ± 22 b and 3:5 ± 0:3 kb, respectively.

A double cylindrical bicrystal is a bicrystal consisting of a cylindrical inside grain with a second grain wrapped around its curved side surface. Using a double cylindrical bicrystal of a Cu-SiO 2 alloy, tensile tests were performed at 800 K under 2 x 10 -4 s -1 . Three specimens cut from the same bicrystal were deformed to three different strains. Preferential formation of grain-boundary cracks around the cylindrical inside grain was observed after the tensile tests. In addition to the occurrence of grain-boundary sliding, the misfit of slip deformation at the grain boundary affects the formation of the grain-boundary cracks.

Instead of conventional Ge semiconductor detectors and NaI(Tl) scintillation spectrometers, an application of a CdZnTe semiconductor (CZT) whose crystal has the dimension of 1 cm cubic to the in situ environmental radioactivity measurement was attempted in deeply affected areas in Fukushima region. Results of deposition density on soil for (134)Cs/(137)Cs obtained seemed consistent, comparing obtained results with those measured by the Japanese government.

The isotope effect describes mass-dependent variations of natural isotope abundances for a particular element. In this pilot study, we measured the Cu-65/Cu-63 ratios in the serums of 20 breast and 8 colorectal cancer patients, which correspond to, respectively, 90 and 49 samples taken at different times with molecular biomarker documentation. Copper isotope compositions were determined by multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). When compared with the literature data from a control group of 50 healthy blood donors, abundances of Cu isotopes predict mortality in the colorectal cancer group with a probability p = 0.018. For the breast cancer patients and the group of control women the probability goes down to p = 0.0006 and the AUC under the ROC curve is 0.75. Most patients considered in this preliminary study and with serum delta Cu-65 lower than the threshold value of -0.35 parts per thousand (per mil) did not survive. As a marker, a drop in delta Cu-65 precedes molecular biomarkers by several months. The observed decrease of delta Cu-65 in the serum of cancer patients is assigned to the extensive oxidative chelation of copper by cytosolic lactate. The potential of Cu isotope variability as a new diagnostic tool for breast and colorectal cancer seems strong. Shifts in Cu isotope compositions fingerprint cytosolic Cu chelation by lactate mono-and bidentates. This simple scheme provides a straightforward explanation for isotopically light Cu in the serum and isotopically heavy Cu in cancer cells: Cu+ escaping chelation by lactate and excreted into the blood stream is isotopically light. Low delta Cu-65 values in serum therefore reveal the strength of lactate production by the Warburg effect.

The effective capture cross section of 243Am for thermal neutrons was measured with an activation method. A sample of 243Am was irradiated for 10 hrs at Kyoto University Reactor, KUR. After the irradiation, the sample was cooled for one month. In the cooling time, 244mAm and 244gAm produced by the irradiation decayed out to 244Cm. The α rays emitted from 243Am and 244Cm were measured with a silicon surface barrier detector. The neutron flux at the irradiation position was monitored using Au/Al and Co/Al wires. The effective capture cross section was deduced as 174.5±5.3b from the α-ray counts and the neutron flux. The quantity r√T/T0 in Westcott's convention was 0.037±0.004. The present result was compared with the effective capture cross sections from the JENDL-3.3 and the Mughabghab evaluations.

Strontium isotopes were fractionated using liquid chromatography with a cryptand (2B,2,2) polymer as a stationary phase. In this study, we observed that the single stage isotope enrichment factor of 84Sr shows the following order, water[6.4×10−3]>MeOH[4.9×10−3]>DMF[1.1×10−3]. The enrichment factors observed in this study did not show a mass‐dependent profile, indicating that the mass‐independent isotope effect affects isotope enrichment phenomena. The mass‐dependent and the mass‐independent isotope effects that influence the enrichment factor of 84Sr are related to the donor number linearly, implying that the solvation strongly affects the isotope effect.

In order to assess the applicability of the Differential Pulse Voltammetry technique to the in-situ measurement of UO2 2+ concentration in the oxide electro-winning process, DPV measurements for UO2Cl2 in molten NaCl-2CsCl were studied. DPV measurement of UO2 2+ in NaCl-2CsCl at 923 K, with a set of optimized parameters (potential sweep rate −0.1 V/s, pulse cycle 0.1 s, pulse width 10 ms and pulse potential height 50 mV), showed a clear current peak at −0.9 V vs. Cl2/Cl−. This was attributed to the reduction of UO2 2+ to UO2 +. The relation between the current peak height and the analytical concentration of the UO2 2+ showed good proportionality in the concentration region up to 0.06 mol.l −1, and the applicability of UO2 2+ concentration measurement by DPV was confirmed up to 0.4 mol.l −1. In order to assess the interference by the coexisting fission product elements to the measurement of UO2 2+ concentration, DPV measurements of UO2 2+ concentration in molten NaCl-2CsCl containing PdCl2, NdCl3, SmCl3 an...

In order to determine the thermal neutron capture cross section of 237Np, the relevant γ emission probabilities of the 312-keV γ-ray from the decay of 233Pa and the 984-keV γ-ray from the decay of 238Np are deduced from the ratio of the emission rate to the activity. The emission rate and activity are measured with a Ge detector and a Si detector, respectively. The measured emission probability for 312-keV γ-ray is 41.6±0.9% and that for 984-keV γ-ray is 25.2±0.5%. The emission probabilities are used to correct the thermal neutron capture cross section of 237Np reported previously, and gives 168±6b. The neutron capture cross section is also determined as 169±6b by α-ray spectroscopic method. The measured emission probabilities and capture cross section are compared with others from references. By averaging these values deduced by different methods, the value of 169±4b is recommended as the thermal neutron capture cross section of 237Np for 2,200 m/s neutrons.

The extraction characteristics of nitric acid with a typical TRUEX (transuranic elements extraction) solvent, the mixture of octyl(phenyl)‐N,N‐ diisobutylcarbamoylmethylphosphine oxide and tri‐n‐butyl phosphate dissolved in n‐dodecane, were studied. From the extraction results of lanthanum, the concentration of CMPO, which was not bound to metal ions or nitric acid, were estimated. The estimated concentration was appropriate in comparison with the extraction results of nitric acid. The applicability of the determined effective CMPO concentration to the formulation of the distribution equilibrium of other f‐elements was confirmed.

Influence of the water content to chemical status of trivalent rare earth ions in calcium nitrate hydrate melt was studied by spectroscopic techniques. Fluorescence spectrometry for Eu(III) in Ca(NO 3 ) 2 · R H 2 O and electronic absorption spectrometry for Nd(III) in Ca(NO 3 ) 2 · R H 2 O were performed for analyzing the changing coordination symmetries through the changes in their hypersensitive transitions. Raman spectroscopic study and EXAFS study were performed for Y(NO 3 ) 3 solutions and Y(III) in Ca(NO 3 ) 2 · R H 2 O for analyzing the oxygen bonding to Y(III). Luminescence lifetime study of Eu(III) and Dy(III) in Ca(NO 3 ) 2 · R H 2 O was performed for evaluating the hydration number changes. Results of these spectroscopic studies indicated that, with the decrease of water content ( R ), the hydration number decreases while the interaction between trivalent rare earth ion and nitrate ion increases. It was also revealed that the symmetry of the coordination sphere gets distorted gradually by this interaction.

消化管の一部が肝と右横隔膜の間に嵌入した病態はChilaiditi症候群と言われ,嵌入臓器のほとんどが結腸である.われわれは絞扼性イレウスを合併し手術を要した比較的稀な小腸型Chilaiditi症候群の1例を術前に診断し治療する経験を得た.症例は85歳の女性で右季肋部痛を主訴に受診,腹部単純X線, CTで小腸型Chilaiditi症候群と診断し第3病日に手術を行った.開腹所見では,肝と横隔膜間に形成された線維性索状物の間に小腸が嵌入した絞扼性イレウスであった.手術では嵌入小腸を整復したが,切除は必要としなかった.自験例ではCTのwindow条件を変えることで小腸のKerckring襞壁を確認し,非侵襲的に嵌入臓器の同定が可能であった.小腸型Chilaiditi症候群は,索状物による絞扼性イレウスを合併しやすく,手術を念頭においた慎重な経過観察が必要である.

Production of Nd 2+ by cathodic electrolysis of NdCl 3 dissolved in molten LiCl–KCl was tested at 773 K. Cyclic voltammetry and differential pulse voltammetry were adopted for the determination of the formal redox potential between Nd 3+ and its divalent or metallic states. UV–visible absorption spectrophotometry was carried out at the vicinity of the cathode during the simultaneous electrolysis at −1.9 V versus Ag/Ag + . During the electrolysis, growth of a new broad absorption band ranging from 450 to 580 nm was observed and this was attributed to the absorption by the chloride complex of Nd 2+ formed by the electrochemical reduction of NdCl 3 . Black precipitate formed in the melt as a result of the constant potential electrolysis over long-period was analyzed by EPMA and ICP-AES and they were confirmed to be fine particles of Nd. The results were discussed in relation to the disproportionation of Nd 2+ and reaction with quartz vessel.

The total evaporation technique of thermal ionization mass spectrometry was applied to the isotopic analysis of chromium. High measurement reproducibility of the chromium isotope ratios was verified (2 S.E.0.05% ((53)Cr/(52)Cr)), while a clear mass fractionation effect was observed by using conventional measurement technique. The chromium isotope ratios analyzed by the total evaporation method were not affected by the sample amount on the rhenium filament (50-500 ng Cr). The isotopic analysis under the coexistence of zinc was also performed, and its effect to the chromium isotope ratios was confirmed.

In order to investigate the redox equilibrium of uranium ions in molten NaCL-2CsCL, UV-Vis absorption spectrophotometry measurements were performed for U4+ and U3+ in molten NaCL-2CsCL at 923 K under simultaneous electrolytic control of their ratio. Prominent absorption bands at 480 and 570 nm were assigned to U3+, and their molar absorptivities were determined to be 1,260±42 and 963±32 mol−1.l.cm−1 respectively. From the dependence of the rest potential of the melt on the spectrophotometrically determined ratio of [U4+]/[U3+], the standard redox potential of the couple U4+/U3+ at 923K was determined to be −1.481±0.004 V vs. Cl2/Cl−. Cyclic voltammetry measurements were carried out for the couple U4+/U3+, and the results agreed well with this standard redox potential value. By the results of cyclic voltammetry, a temperature dependence of the standard redox potential was found to be −2.094+6.639×10−4 T (T=823-923 K).

The solubility of U(VI) hydrous oxide was measured in the hydrogen ion concentration (pHc) range from 4 to 6 at 25±1°C in a NaClO4 solution. The experiment was carried out by oversaturation method at ionic strength I=0.1, 0.5 and 1.0 and by undersaturation method at I=1.0. The solid phase was found to be composed of a mixture of UO3.2H2O and UO2 (OH)2 by XRD. The concentration of U(VI) was measured by inductively coupled plasma mass spectrometry (ICP-MS), and was analyzed to obtain the solubility products (Ksp ), by taking into account the participation of the U(VI) hydrolysis species such as (UO2)2 (OH)2 2+ By using the literature values of the hydrolysis species and by using the specific interaction theory (SIT), the log Ksp ° value at the standard state (I=0) was determined to be log Ksp °=—22.46±0.10. Possible differences in the log Ksp° values due to different solid phases were recognized.

The two-dimensional inclusion problem of elasticity has been extended to treat general non-elliptic shapes described as ( x 1 2 ) p / 2 + ( x 2 2 / α 2 ) p / 2 ≤ 1 , p ≥ 2. By using the Green function, the average Eshelby tensors are evaluated and elastic strain energy of the superelliptic inclusion is calculated for a material with cubic elastic anisotropy. In addition, by introducing the isotropic interface energy, equilibrium inclusion shapes to minimize the sum of elastic strain energy and interface energy are discussed as a function of the size and shape of the two-dimensional inclusion. It is found that an intermediate shape between a circle and a square or between an ellipse and a rectangle can be a minimum-energy shape under certain sets of given conditions.

SummaryThe solubility of uranium(IV) hydrous oxide was measured at 25 °C in NaClO4solution containing Na2S2O4as a reducing agent in the pH range from 12 to 14. The experiment was carried out from oversaturation atI= 0.5, 1.0 and 2.0 mol/dm3(M). The solubility data were analyzed to obtain the hydrolysis constants (βm) of U(OH)m(4-m). By taking the specific ion interaction theory (SIT) for ionic strength corrections and by using the solubility product logKsp° = −53.93 ± 0.20, the hydrolysis constants atI= 0, log β5°6° = 48.95 ± 1.01, were determined together with the ion interaction coefficients of U(OH)5−and U(OH)62−.

The volatility of tellurium and some other fission products was radiochemically studied in heated nitric acid solutions. As tracers 121Te produced by bremsstrahlung of an electron LINAC and other fission products produced by neutron irradiation were used. The distribution rate of radionuclides between the mother solution and the condensate, was considered as volatility, and was determined. The volatility of tellurium was found to be small and close to that of cesium. Volatilization tests were also performed in the presence of large amounts of solutes.

Purpose: Angiogenesis plays an important role in a multitude of biological processes including those of tumorigenesis and cancer progression. Hypoxia is the prime driving factor for tumor angiogenesis and the family of hypoxia-inducible factors (HIFs) plays a pivotal role in this process. The role of HIF in tumor angiogenesis has been underscored in different carcinomas but yet to be reported for colorectal carcinomas. Experimental Design: In this study, we examined HIF [HIF-1α (HIF1) and HIF-2α (HIF2)] expression in 87 curatively resected colorectal carcinoma samples, and the results were correlated with clinicopathological factors, microvessel density, cyclooxygenase 2 expression, and patient prognosis. Results: HIF1 (44.8%) was more frequently expressed than HIF2 (29.9%). Most of the clinicopathological factors representing the tumor aggressiveness were significantly correlated with overexpression of HIF2 but not with HIF1 expression. HIF2 expression had direct correlation with microvessel density and cyclooxygenase 2 expression. and, in contrast, HIF1 expression had a weak but significant inverse correlation in T1 and T2 tumors only. HIF2 expression alone and the combined expression of HIF1 and HIF2 had significant impact on patient survival. In the multivariate analysis, however, only the combined expression of HIF1 and HIF2 remained independently significant. Conclusions: Taken together, our results suggest that HIF2 expression may play an important role in angiogenesis and that the combined expression of HIF1 and HIF2 may play an important role in tumor progression and prognosis of colorectal carcinomas. Therefore, HIF expression could be a useful target for therapeutic intervention.

In order to enhance the understanding of the redox equilibriums of uranyl ions in molten NaCl-2CsCl eutectic salt UV-Vis absorption spectrophotometry measurements were performed for UO2 2+ in molten NaCl-2CsCl at 923 K under simultaneous electrolytic control of their ratio. A prominent absorption band at 395 nm was assigned to UO2 +, and its molar absorptivity was determined to be 832±27 mol-1·l·cm-1. From the dependence of the rest potential of the melt on the spectrophotometrically determined ratio of [UO2 2+]/[UO2 +], the standard redox potential of the couple UO2 2+/UO2 + was determined to be −0.903±0.007 V vs. Cl2/Cl—.

Cu-0.78 mass%Si bicrystals are internally oxidized at various conditions and morphological evolution of amorphous SiO2 formed on a grain boundary (GB) is observed. After the reaction of Si atoms with oxygen, a film-like SiO2 phase with holes is initially formed on GB of Cu. At temperatures used for the internal oxidation, the holes rapidly grow and the morphology of the film-like SiO2 changes to a particulate equilibrium shape through formation of two-dimensional SiO2 network and its subsequent breakup. During the morphological evolution, the volume of SiO2 on GB is conserved. The morphological evolution of SiO2 on GB is caused by diffusional flow of matter to decrease the sum of Cu/SiO2 interface and Cu grain-boundary energies. The activation energy Q of the morphological evolution is obtained as Q ≈ 290 kJ/mol. Among the values of activation energies reported in the previous studies on diffusion in SiO2, Q ≈ 290 kJ/mol is close to that for the volume-diffusion of SiO in SiO2, QSiO ≈ 268 kJ/mol. This supports that the morphological evolution of SiO2 on GB is controlled by the volume-diffusion of SiO in SiO2.