1,722,307 research outputs found
Project 11 Studies on Actinides and Fission Products Performed at the KURRI Hot Laboratory
Full text linkPR11-1 Apparent Formation Constant of Metal Ions with Humic Substances; Modelling. Sasaki T. Kobayashi T. Koukami T. Uehara A. Fujii T. Yamana H. Moriyama H.PR11-2 Temperature Effect on the Solubility and Solid Phase of Tetravalent Metal Hydroxide. Kobayashi T. Sasaki T. Uehara A. Fujii T. Yamana H. Moriyama H.PR11-3 Research on The Behavior of Actinides and FPs in Fuel Debris. Sato N. Kirishima A. Hirano M. Sasaki T. Kobayashi T. Takeno Y. Uehira A. Fujii T. Takamiya K. Yamana H.PR11-4 Effect on Borosilicate Glass Structure by Neutron Irradiation. Nagai T. Miyauchi A. Morikawa Y. Uehara A. Fujii T.PR11-5 Ligand Exchange of Uranium (IV) Chloro- and Fluoro- Complexes in High Temperature. Uehara A. Nagai T. Fujii T. Moriyama H. Yamana HPR11-6 Evaluation of Parameters Governing Anodic Dissolution of U-Zr Alloy in Molten LiCl-KCl. Iizuka M. Sakamura Y. Fujii T. Uehara A. Yamana H.PR11-7 Electrochemistry and Structural Analysis of Cations in Molten Sub-halide Systems:. Matsuura H. Nezu A. Akatsuka H. Uehara A. Yamana H. Fujii T.PR11-8 Polarization Effect of Chloride Ions on Uranyl Ion in Molten LiCl. Ohtori N. Ishii Y. Uehara A. Fujii T. Yamana H.PR11-9 Study of Isotope Separation of Strontium and Calcium via Chemical Exchange Reaction. Hazama R. Sakuma Y. Ito A. Fujii T. Fukutani S. Shibahara Y.PR11-10 Experimental and Calculated Optical Properties of Molten Alumnium Chloride Melts. Goto T. Hachiya K. Uehara A. Fujii T. Yamana H.PR11-11 Precipitation Behavior of Trivalent Dysprosium Ion by Reaction with Oxide Ion in CaCl2–LiCl Molten Salt. Sekimoto H. Uehara A. Fujii T. Yamana H.PR11-12 Elucidation of the Uptake Route of Radionuclides in Deciduous and Coniferous Trees Using Radio Cesium and Radio Potassium in Annual Tree Rings. Ohta T. Kubota T. Shibahara Y. Fukutani S. FujiiT. Igarashi T. Mahara Y.PR11-13 Photon activation analysis of alkali earth elements and arsenic with bremsstrahlung at the KURRI-LINAC. Kubota T. Fujii T. Fukutani S. Shibahara Y. Ohta T.PR11-14 Study of Applicability of Isotopic Ratio Measurement for Analysis of Radionuclide in Environmental Samples. Shibahara Y. Kubota T. Fukutani S. Fujii T. Shibata T. Yoshikawa M.PR11-15 Tracing Halogen and Noble Gas Recycling in the Northern Izu Subduction Zone by Molten NaCl-CsCl Eutectic Neutron Irradiation and Noble Gas Mass Spectrometry. Sumino H. Kobayashi M. Nagao K. Okumura R. Sekimoto S. Fujii T.PR11-16 Volcanic and Tectonic History of Philippine Sea Plate (South of Japan) Revealed by 40Ar/39Ar Dating Technique. Ishizuka O. Fujii T. Okumura R. Sekimoto S.PR11-17 Ar–Ar Age Determination of Minamitorishima Fluoride Addition Effect on Voltammograms and UV-vis Spectra of Neodymium Cation in Molten Chlorides. Hirano N. Sumino H. Fujii T. Okumura R. Sekimoto S
Functional effects of the hadal sea cucumber Elpidia atakama (Echinodermata: Holothuroidea, Elasipodida) reflect small-scale patterns of resource availability
Full text linkHolothuroidea represent the dominant benthic megafauna in hadal trenches (similar to 6,000-11,000 m), but little is known about their behaviour and functional role at such depths. Using a time-lapse camera at 8,074 m in the Peru-Chile Trench (SE Pacific Ocean), we provide the first in situ observations of locomotory activity for the elasipodid holothurian Elpidia atakama Belyaev in Shirshov Inst Oceanol 92: 326-367, (1971). Time-lapse sequences reveal 'run and mill' behaviour whereby bouts of feeding activity are interspersed by periods of locomotion. Over the total observation period (20 h 25 min), we observed a mean (+/- SD) locomotion speed of 7.0 +/- 5.7 BL h(-1), but this increased to 10.9 +/- 7.2 BL h(-1) during active relocation and reduced to 4.8 +/- 2.9 BL h(-1) during feeding. These observations show E. atakama translocates and processes sediment at rates comparable to shallower species despite extreme hydrostatic pressure and remoteness from surface-derived food
Alkaline phosphatase encapsulated in gellan-chitosan hybrid capsules
Full text linkThis is a preprint of an article published in [Fujii, T; Ogiwara, D; Ohkawa, K; Yamamoto, H.,Alkaline phosphatase encapsulated in gellan-chitosan hybrid capsules,MACROMOLECULAR BIOSCIENCE,Vol 5,394-400(2005)]ArticleMACROMOLECULAR BIOSCIENCE. 5(5): 394-400 (2005)journal articl
Fatigue damage characterization and percolation in plain-weave carbon fiber-epoxy composites
No full textThe concept of ‘damaged unit cell’ was employed to describe the tensile fatigue damage evolution in plain-weave carbon-epoxy composites. The fatigue damage was connected to the development of cluster of damaged unit cells and their distribution, considering the measurements by thermoelastic damage analysis (TDA). Internal damage state was also observed by SEM. The experimental results showed that the size ratio of the maximum damaged unit cell cluster, Cmax, rapidly increased after the damaged unit cell ratio p exceeded 0.527, called ‘percolation threshold’ pc. This threshold announced the fatigue final failure, which occurred with fast accumulation of transverse cracks, wider local delamination and fibers breakage, once p exceeded pc. Since the relationship between the averaged thermoelastic damage response and Cmax was nearly linear, the fatigue damage evolution involved clustering of damaged unit cells. The fractal dimension D of the damaged unit cells cluster increased up to a steady state value Dc, when p exceeded pc, showing the faster fatigue damage evolution. Finally, the fatigue damage evolution was predicted using the concept of percolation and mutual interference between damaged units
FATIGUE BEHAVIOUR OF OPEN HOLE CARBON TEXTILE COMPOSITE WITH MICROFIBRILS CELLULOSE MODIFIED EPOXY
No full textThe strength and the failure mechanisms of notched composite materials are of considerable importance in several industrial applications where joints and bolts are unavoidable. They become the main concern when notched composite components are subjected to repeated cyclic loadings. To enhance the fatigue life of composite materials, research efforts were also dedicated to the toughening mechanisms of resin systems. Thermoset systems were modified to overcome their brittle nature by a second phase consisting of nano- or micro- sized fillers (such as nanotubes, nano-fibres, nano-particles, etc.). To this purpose, the family of hybrid nano/micro enhanced resin systems has been extended exploiting microfibrils cellulose (MFC). Cellulose is the most abundant natural homo-polymer and one of the most promising renewable and environmentally friendly resources. The aim of this experimental study was to contribute on the understanding the effect of hybrid microfibrils cellulose epoxy resin (MFC content 0.3% of the resin weight) on the tensile fatigue performance of open hole carbon textile composites. This comprehensive study had three steps. The first dealt with the pre-fatigue quasi-static tensile behavior to measure the relevant mechanical properties, and understanding the damage modes initiation and development around the hole by digital image correlation (DIC) and scanning electron microscope (SEM) observations. The second aimed to detect the effect of the hybrid microfibrils cellulose epoxy resin on the fatigue life diagram of the open hole textile composite by tensile-tensile cyclic loading. Moreover, in this step, the damage development during cyclic loading was observed by DIC, SEM and X-ray micro-CT. Finally, the third step was dedicated to post-fatigue quasi-static tensile behavior, after one million cycles, to assess the retention of the tensile strength and the distribution of the damage comparing to the pre-fatigue quasi-static results. The MFC hybridization of the matrix improved the damage tolerance of the open hole carbon textile composite leading to the extension of the fatigue life. The enhanced performance was mainly connected to the bridging effect of cellulose microfibrils preventing or delaying the cracks propagation in the matrix and along the fiber-matrix interface
Fatigue damage mechanisms in carbon textile reinforced microfibrils cellulose modified epoxy
No full textThe experimental study aimed to understand the effects of micro-fibrillated cellulose (MFC) modified epoxy resin on the damage evolution of unnotched and notched (open hole) carbon plain weave textile composites, during tensile quasi-static and fatigue loadings. The initiation and propagation of the damage was studied assisting the tests with a high speed digital camera for measurement of the full field strain by the digital image correlation technique (DIC). The damage was observed by X-ray micro computed tomography (micro-CT). The hybridization of the matrix allowed an improved damage tolerance of the composite leading to increase of the quasi-static tensile strength and extension of the fatigue life. The enhanced performance was connected to the bridging effect of cellulose microfibrils preventing or delaying the cracks propagation in the matrix and along the fibers interface
Fatigue performance of micro-fibrillated cellulose and rubber nanoparticle hybrid epoxy resin reinforced carbon plain weave composites
No full textThe present work gives a contribution on understanding the effects of hybrid epoxy resins, enhanced with micro-fibrillated cellulose (MFC) and carboxylated nitrile-butadiene rubber nanoparticles (XNBR), on the tensile-tensile cyclic loading of carbon fibres plain weave textile composites. The experimental investigation shows the effects of four different combinations of MFC and XNBR weight contents in the epoxy resin (from 0% to 0.5% of MFC and from 0% to 3% of XNBR) on the fatigue behaviour compared to the composite with pure resin counterpart. The results of fatigue tests reveal on one hand a considerable extension of the fatigue life of the composite having the larger content of MFC, while a reduction increasing the XNBR weight. On the other hand, some combinations of MFC and XNBR delay the stiffness degradation of the composite
Percolation of fatigue damage in plain-weave textile reinforced composites
No full textSeveral studies have investigated the mechanical response of textile reinforced composites under cyclically repeated loadings (fatigue). However, there is still a need for accurate quantitative evaluation of the fatigue damage accumulation and accurate predictive models to ensure the safe design of textile composite components. In this study, a thermography based method has been developed to detect the evolution of the fatigue damage in plain-weave carbon fiber/epoxy composites. The method adopts the unit cell as the unit of damage evolution (damaged unit cell). The fatigue damage has been related to the development of clusters of damaged unit cells and their distribution on the surface of the tensile fatigued specimen, considering the thermoelastic damage analysis (TDA). Percolation theory was also applied to demonstrate how the number and properties of the clusters, formed by irregularly distributed damaged unit cells, affect the entire system. The method showed that the size ratio of the maximum damaged unit cell cluster, Cmax, increased rapidly after the damaged unit cell ratio exceeded the ‘percolation threshold’ pc. This threshold announced the fatigue final failure, which occurred with rapid accumulation of transverse cracks, wider local delamination and fibers breakage. The arrangement of the damaged unit cells was also quantitatively evaluated using the fractal concept. The fractal dimension D of the damaged unit cells cluster increased up to a steady state value Dc. Beyond this value, the fatigue damage had a faster evolution when p exceeded pc. Finally, the fatigue damage evolution was predicted using the concept of percolation and mutual interference between damaged units
Damage mechanism in open hole carbon textile reinforced epoxy composites
No full textIn this experimental investigation the damage mechanisms and the damage evolution were observed during tensile quasi-static and cyclic loadings of open hole carbon balanced plain weave reinforced epoxy laminates. The initiation and propagation of the damage in open hole (diameter 5 mm) notched specimens were studied measuring the full field strain by the digital image correlation (DIC) and observing damage modes by X-ray micro-CT. The DIC maps of the strain components and the X-ray micro-CT observations highlighted similar damage concentrations and damage mechanisms for both loading conditions. In the beginning of the fatigue life (about 10%) and for a static load of almost 70% of the strength, the damage was localized between three different strained zones and limited in a very narrow area at the edge of the hole. A slow increase of delamination was observed from the hole edge up to 90% of the fatigue life and for a static load approaching 90% of the ultimate stress. Finally, the fast diffusion of the strain concentration and delamination led to the complete failure of the tows at the hole edge
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