Re-evaluation of Radiation-Energy Transfer to an Extraction Solvent in a Minor-Actinide-Separation Process Based on Consideration of Radiation Permeability

ABSTRACT

Absorbed-dose estimation is essential for evaluation of the radiation tolerance of minor-actinide-separation processes. We propose a dose-evaluation method based on radiation permeability, with comparisons of heterogeneous structures seen in the solvent-extraction process, such as emulsions forming in the mixture of the organic and aqueous phases. A demonstration of radiation-energy-transfer simulation is performed with a focus on the minor-actinide-recovery process from high-level liquid waste with the aid of the Monte Carlo radiation-transport code PHITS. The simulation results indicate that the dose absorbed by the extraction solvent from alpha radiation depends upon the emulsion structure, and that from beta and gamma radiation depends upon the mixer-settler-apparatus size. Non-negligible contributions of well-permeable gamma rays were indicated in terms of the plant operation of the minor-actinide-separation process.     

Contribution of metal vapor mass at periphery part of pulsed arc to electromagnetic force in weld pool

The arc welding has been used in various welding methods because it is inexpensive and high in strength after welding. However, it is a problem that accidents such as collapse of the bridge occur because of the welding defects. The welding of low cost and high productivity is required without the welding defects. The pulsed TIG welding is inexpensive and capable of high‐quality welding. The electromagnetic force contributing to penetration changes because the transient response of arc temperature and iron vapor generated from anode occurs. However, the analysis of pulsed TIG welding with metal vapor has been elucidated only metal vapor concentration near anode with transient phenomenon and heat flux. Thus, the theoretical elucidation of penetration depth with control factor has not been researched. In this paper, the contribution of metal vapor mass at the periphery part of pulsed arc to the electromagnetic force in the weld pool is elucidated. As a result, the iron vapor mass at periphery part decreased with increasing the frequency. The iron vapor was stagnated at axial center within one cycle. The electromagnetic force to the penetration depth direction in weld pool increased at axial center. Therefore, the metal vapor mass at periphery part plays an important role for the electromagnetic force increment at axial center.     

A slotted post-wall waveguide array with interdigital structure for 45/spl deg/ linear and dual polarization

This work proposes a dual-polarized planar antenna; two post-wall slotted waveguide arrays with orthogonal 45/spl deg/ linearly-polarized waves interdigitally share the aperture on a single layer substrate. Uniform excitation of the two-dimensional slot array is confirmed by experiment in the 25 GHz band. The isolation between two slot arrays is also investigated in terms of the relative displacement along the radiation waveguide axis in the interdigital structure. The isolation is 33.0 dB when the relative shift of slot position between the two arrays is -0.5/spl lambda//sub g/, while it is only 12.8 dB when there is no shift. The cross-polarization level in the far field is -25.2 dB for a -0.5/spl lambda//sub g/ shift, which is almost equal to that of the isolated single polarization array. It is degraded down to -9.6 dB when there is no shift.     

Facile optical resolution of amino acid esters via hydrolysis by an industrial enzyme in organic solvents

Racemic amino acid esters were optically resolved via hydrolysis in organic solvents by the catalysis of an industrial alkaline protease, “Alcalase”. The products which were composed mainly of L-amino acids were insoluble and easily separated by filtration. The activity of the enzyme and enantiomeric excess of the products were significantly dependent on the nature of solvent and the water content in the reaction media. Generally, high values of enantiomeric excess were obtained at low water contents. Many natural and unnatural amino acids were resolved by this method.     

An analysis of a waveguide T junction with an inductive post

The authors analyze the T junction with an inductive post, taking its diameter into account for the case where the current distribution is assumed on the surface of the post. A single cylindrical post placed in a T junction improves the impedance matching and compensates the junction discontinuity in a wide frequency band. The effects of the design parameters, such as the diameter of the post and its location, are clarified. The measured return loss is accurately predicted. On the basis of this analysis, an effective design procedure for the T junction is proposed, and the reflection below -30 dB is realized over 4% bandwidth     

Oxyphilic cell variant of endometrioid adenocarcinoma

A case of oxyphilic cell variant of endometrioid adenocarcinoma is presented. To the best of our knowledge, there have been only three such cases reported in the English literature. The patient was a 35-year-old Japanese female (gravida 0, para 0). She was slightly obese with profuse vaginal bleeding. Histological examination of the resected uterus revealed endometrioid adenocarcinoma with an exclusive oxyphilic cell component. There was no evidence of myometrial invasion nor lymph node metastases. Reported cases of oxyphilic cell variant of endometrioid adenocarcinoma, including the present case, were stages 0-1 and grades 1-2. Although further study is necessary to evaluate this variant, oxyphilic cell variant seems to be an early stage of adenocarcinoma and should be differentiated from eosinophilic metaplasia and other types of adenocarcinoma of the endometrium.     

Water structure and improved mechanical properties of phospholipid polymer hydrogel with phosphorylcholine centered intermolecular cross-linker

We investigated the water structure and the mechanical properties of 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer hydrogels cross-linked with a novel hydrophilic 2-(methacryloyloxy)ethyl-[N-(2-methacryloyloxy)ethyl]phosphorylcholine (MMPC) for soft contact lenses (SCL) applications and commercial methacrylic cross-linkers were in addition used for comparison with MMPC. Water structure in hydrogels, which influences the protein adsorption by dehydration was determined by differential scanning calorimetry. MMPC increased the freezing water content of the MPC polymer hydrogel compared with hydrophilic N,N′-methylenebisacrylamide (BIS) at the same water content. MMPC also improved fracture strength of the MPC polymer hydrogel to 120 kPa in tensile, which was considerably higher than that hydrogel cross-linked with BIS. It is suggested that MMPC shows higher cross-linking reactivity with MPC than BIS. We concluded that the MMPC increase both the free water content and the tensile properties. The MPC polymer hydrogel cross-linked with MMPC can be a useful SCL biomaterial.     

Ethanol production from raw starch by a recombinant yeast having saccharification and fermentation activities

In order to develop a method for converting raw starch into ethanol efficiently, direct fermentation of ozonized raw starch using a recombinant yeast was investigated. Ozonolysis was carried out as a pretreatment to convert raw starch into ethanol rapidly and efficiently, and then the effect of the ozone degradation conditions on the degree of polymerization and the amount of amylose in a raw starch was determined. Since the degree of polymerization was low and the amount of amylose was high, raw starch treated with an ozone concentration of 40 gm^?3 and an ozonation time of 30 min was the material chosen for alcohol fermentation. Though the recombinant yeast could not convert the untreated raw starch, it converted the soluble starch and the ozonized raw starch at a comparatively high yield into ethanol. About 56% of the ozonized raw starch decomposed, and the ethanol concentration obtained from the ozonized raw starch was markedly greater than that obtained from untreated raw starch. The dynamic behavior of cell growth, substrate degradation, and ethanol production was examined in a continuous culture under various dilution rates, and the optimal dilution rate, ie 0.15 h^?1, was determined for maximizing the ethanol productivity (amount of ethanol produced per unit time). © 2002 Society of Chemical Industry     

Spectral transmittance of organic dye-doped glass films obtained by the solgel method

The spectral transmittance of colored glass films synthesized by the solgel method is presented. The film was formed on a glass slide by dipping it into an organic dye-doped solution and, thereafter, by putting it into a furnace for solidification. Three dyes, Methylene Blue, Eosin, and Uranine, were used that exhibit transparent blue, pink, and yellow colors, respectively, when they are dissolved in the starting solution. We clarify how the spectral transmittance of the films varies with the solidification temperature. The films doped with two of the three dyes that exhibit violet, orange, and green colors are also synthesized, and their transmittance is measured. Moreover, the chemical durability of the films and the transmittance change caused by aging and illumination are examined.     

Attribute-based quality classification of academic papers

Investigating the relevant literature is very important for research activities. However, it is difficult to select the most appropriate and important academic papers from the enormous number of papers published annually. Researchers search paper databases by combining keywords, and then select papers to read using some evaluation measure—often, citation count. However, the citation count of recently published papers tends to be very small because citation count measures accumulated importance. This paper focuses on the possibility of classifying high-quality papers superficially using attributes such as publication year, publisher, and words in the abstract. To examine this idea, we construct classifiers by applying machine-learning algorithms and evaluate these classifiers using cross-validation. The results show that our approach effectively finds high-quality papers.