Current status and future plans of Advanced ORIENT Cycle strategy

For minimization of the ecological risks inherent in nuclear fuel recycling, a new fuel cycle paradigm was proposed and its key technology developments have been carried out as a part of the Advanced Optimization by Recycling Instructive Elements (Adv.-ORIENT) Cycle strategy. The basic concept of the Adv.-ORIENT Cycle uses a three-pronged approach, separation, transmutation and utilization of nuclides and elements, based on the FBR fuel cycle. Fundamental research studies done in Adv.-OEIENT Cycle [Phase-1: 2006-2010] have led to the following findings.

1.

Cs and Sr separation and its utilization: Silica gel loaded with ammonium molybdophosphate (AMP) and hybrid organic microcapsules with crown ether D18C6 were investigated to chromatographically separate Cs and Sr, respectively. In particular, uptake experiments of Cs from solution simulating the spent fuel solution obtained were carried out by a batch method, and the uptake rates achieved were more than 90%.

2.

Minor actinide (MA)/lanthanide/fission product (FP) separation: A tertiary pyridine type resin (TPR) can be used to recover Am, Cm and lantanide elements with a high separation factor by a chromatographic method from spent fuel solution. The TPR can be used with hydrochloric acid (HCl) as well as nitric acid (HNO₃).

3.

Ru, Ph, Pd and Tc separation: A catalytic electrolytic extraction (CEE) method can effectively separate Ru, Ph, Pd and Tc. High recovery ratios of Ru, Rh, Pd, Tc, Se, etc. were achieved using HCl solutions. Rh co-deposition significantly accelerated reduction of Ru, Tc and Re using HNO₃ solutions.

4.

Ru, Ph, Pd and Tc utilization: Based on the mixed deposit obtained from the CEE experiments, Ru/Rh/Pd/Tc(Re)-Pt electrodes provided the highest catalytic reactivity in the electrolytic production of hydrogen in an alkali solution.

5.

Basic engineering research: Results of corrosion experiments showed that Hastelloy-B and Ta had a good anti-corrosive property in a wide range of HCl concentrations. The basic thermo-chemical stability of TPR and tri-butyl phosphorous (TBP, as a reference) was also experimentally studied, and the process safety conditions to be specified for practical use of TPR could be identified.

     

Improvement and Application of a P-Wave Measurement System for Laboratory Specimens of Sand and Gravel

A compression (P-) wave velocity measurement system was improved to evaluate vertical small strain Young's modulus of sand and gravel specimens. The wave was generated using a multi-layered piezoelectric actuator attached to the top cap of a triaxial cell specimen and received with two piezoelectrical accelerometers at two different positions on the specimen's side. This system includes use of a peak to peak travel time based on excitation records that were triggered by single pulse or sinusoidal wave and stacked for 128 times. The vertical Young's moduli (E_d) obtained by using this dynamic measurement were then compared with the statically measured vertical Young's moduli (E_s) that were evaluated by conducting small unloading/reloading cycles on the same specimen. Two series of tests using medium and large size specimens, respectively, were conducted on three kinds of material namely Toyoura sand (D₅₀=0.23 mm), sieved Chiba gravel (D₅₀=3 mm) and original Chiba gravel (D₅₀=6 mm). No significant effect of specimen size was observed on E_s and E_d of Toyoura sand. E_d was found larger than E_s in all three types of materials while the difference between the two was not the same. Combined effects of the dry density and the wavelength in the dynamic measurement were then discussed.     

Effects of System Compliance on Liquefaction Behavior of Thin Sandy Layer in Undrained Cyclic Triaxial Tests

In a case history of dip slope failure caused by the 2004 Niigata-ken Chuetsu Earthquake, it has been reported that the slope contained a thin sandy soil layer. The layer may have liquefied if it had been saturated at the time of the earthquake. Undrained cyclic triaxial tests comprise one of the available experimental approaches for evaluating the liquefaction behavior of such thin sandy soil layers. In this study, a series of undrained cyclic triaxial tests was performed on specimens containing an artificial sand layer in order to investigate the effects of system compliance that are possibly induced by partial drainage caused by the changes in volume of the filter paper used to saturate the sand layer and the local drainage at the interface among the specimen, the top cap and pedestal, and the rubber membrane. The observed liquefaction behavior depended on the thickness of the sand layer under otherwise similar conditions, suggesting the significant effect of system compliance. By conducting special tests, while correcting the partial drainage, it was possible to reduce its effect on the liquefaction behavior. Cylindrical specimens with a top cap and pedestal, all having the same diameter, exhibited a smaller effect from partial drainage than prismatic specimens with an oversized top cap and pedestal.     

Quantitative analysis for controllability of symmetric control systems

This paper is concerned with the controllability of systems possessing symmetries. In particular, we aim to give a lower bound for the number of functioning modules needed to ensure the controllability of the entire symmetric system. Our concern is the characteristics derived from the symmetry of the systems, and not from the numerical information nor from the sparsity of the connections among the modules. If structurally independent modules are connected, only one functioning module would suffice to ensure the controllability. For symmetric systems, however, it is shown that we need more than one functioning module for the entire system to be controllable. We treat systems of general symmetry and show the lower bound based on group representation theory.     

Triaxial apparatus equipped with elastic waves and matric suction measurement techniques

A recently developed technique for elastic wave measurement, a disk transducer method, and a pressure membrane technique for suction measurement were merged into a modified triaxial testing apparatus enabling the procurement of both the elastic waves and the matric suction of a cylindrical specimen. The apparatus was employed to evaluate the variation in suction in sandy soil possessing a low range of suction (less than 100?kPa). Fine sand with two types of fines, namely, non-plastic silt and kaolin clay, was mixed with Toyoura sand in order to prepare sandy soil specimens. Both compressional and shear wave velocities were evaluated in conjunction with the associated matric suction. The matric suction was varied by injecting water into the specimens, and the relevant elastic wave velocities were obtained by a disk transducer. This research has corroborated the applicability of the disk transducer method to unsaturated soil specimens as well as the effects of matric suction on the mechanical behaviour of sandy soils possessing a low range of suction.     

Soluble fullerene-based n-channel organic thin-film transistors printed by using a polydimethylsiloxane stamp

A polydimethylsiloxane stamp was applied for the first time to the fabrication of n-channel thin-film transistors based on soluble small molecule organic semiconducting materials. The stamping method was found to facilitate film transfer onto a gate insulator surface irrespective of its surface free energy. We used [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) and C(60)-fused N-methylpyrrolidine-meta-dodecyl phenyl (C60MC12) as n-channel materials. The stamped thin-film transistors of C60MC12 achieved a high electron mobility of 0.39 cm(2)/(V s) and a current on-off ratio of 1 × 10(7). The mobility of the stamped C60MC12 thin-film transistors did not depend much on the surface free energy of the SiO(2) gate insulator with and without surface treatment using a silane-coupling reagent. In particular, the stamped C60MC12 thin-film transistor exhibited a relatively high mobility of 0.1 cm(2)/(V s) on a high energy surface of untreated SiO(2). In addition, a complementary inverter composed of an n-channel and a p-channel stamped thin-film transistor was demonstrated for the first time, which exhibits a maximum gain of 63 at a supply voltage of 50 V.     

Synthesis of epoxy resin–silica nanocomposites provided from perhydropolysilazane as a curing reagent and the precursor of silica domain

Epoxy resin–silica nanocomposites with spherical silica domains with 29.0 nm in diameter in an epoxy resin matrix were synthesized from Bisphenol‐A type epoxide monomer, 2,2‐bis(4‐glycidyloxyphenyl)propane (DGEBA), and perhydropolysilazane (PHPS, ? [Si₂? NH]_n? ). The volume fraction of silica domain in the composite varied from 5.4 to 37.8 vol % by varying the feed ratio of PHPS to the epoxide monomer. The reaction mechanism of epoxy group and PHPS was investigated by using glycidyl methacrylate as a model compound of the epoxy monomer by ¹H‐nucular magnetic resonance and Fourier transform infrared spectrometry. Ammonia gas provided by the decomposition of PHPS with moisture converted PHPS to silica and cured the epoxy monomer. The curing of epoxy monomer preferably proceeded than the conversion of silica. The addition of 1,4‐diaminobutane drastically accelerated the rate of curing; white and hard epoxy resin–silica nanocomposites were obtained. The good thermal stability of the composite prepared with DGEBA/PHPS/1,4‐diaminobutane was observed by thermogravimetric analysis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Evolutionary relationship of hepatitis C, pesti-, flavi-, plantviruses, and newly discovered GB hepatitis agents

Twelve bacteria were isolated from two effluent sources of Shaw-Wallace Gelatins, Jabalpur. Six bacteria from dicalcium phosphate plant effluent (pH-5) and six from main drain of the factory (pH-10) were isolated. Two facultatively acidophilic and two facultatively alkalophilic bacteria were selected and tentatively identified as Plesiomonas shigelloides, Aeromonas hydrophilla, Klebsiella pneumoniae and Staphylococcus saprophyticus respectively. Acidic amylases were produced in higher amounts on 4th day of incubation by Plesiomonas shigelloides and on 6th day by Aeromonas hydrophilla. Alkaline amylases were produced in higher amounts on 4th day of incubation by Klebsiella pneumoniae and on 8th day by Staphylococcus saprophyticus in vitro.     

Usefulness and limitation of phylogenetic analysis for hepatitis C virus core region: application to isolates from Egyptian and Yemeni patients

We report here the nucleotide sequences of the core region of HCV isolates from Egyptian and Yemeni patients and the method for classifying these HCV isolates by phylogenetic analysis. Sequence comparison suggested that the genotypes of these isolates were the same. Preliminary phylogenetic analysis of the HCV core region indicated that the genotypes of both isolates were 1c. However, an additional phylogenetic tree of the HCV core region constructed using a greater number of HCV isolates than that used in the preliminary analysis and on the basis of alignment of nucleotide sequences in an appropriate length indicated that the genotypes of these isolates were 4 and not 1c. For a more detailed analysis, the nucleotide sequences of the HCV E1 region as well as the core region for the same Yemeni patient were determined. A phylogenetic tree of the E1 region confirmed that the genotype of the HCV isolate from the Yemeni patient was 4. These data indicate that even when classifying HCV isolates using phylogenetic analysis, the misclassification would occur if care is not taken regarding the number and sequence lengths of the isolates included in the analysis.     

Analysis of generated power of ETS-VII during solar activity maximum period

The generated power degradation of a satellite in a low earth orbit during high solar activity period has been compared with the power degradation of a satellite during low solar activity period. A degradation prediction method is developed for this study. As a result, the effect of a large solar flare on solar cell degradation is found to be negligible in a low earth orbit. This is because the effects of shield thickness and inclination are thought to be greater than that of degrees of solar activity.