The diffusivity of oxygen in liquid copper-lead alloys

The oxygen diffusivity in liquid copper-lead alloys at 1403 K (1130° C) was measured using the electrochemical cell: Ni−NiO/ZrO₂(+CaO)/O in liquid Cu−Pb alloy(I)/ZrO₂(+CaO)/O in liquid Cu−Pb alloy (II). Oxygen in liquid Cu−Pb alloy (I) was transferred to the right by applying a preselected voltage between the two liquid Cu−Pb alloys. The oxygen diffusivity in liquid Cu−Pb alloy(I) was calculated from the emf change with time between the Ni−NiO and liquid Cu−Pb alloy (I) electrodes. The results were: It was found that the oxygen diffusivity in liquid copper-lead alloys did not change drastically over the entire composition range, in contrast with that reported by other investigators for liquid copper-nickel alloys. The oxygen diffusivity in pure liquid lead agreed with the results of our previous work using an FeO−Fe₃O₄ mixture as a sink for oxygen.     

Effect of the Atomic Ratio of Ba to Ti on Optical Properties of Gold-Dispersed BaTiO3 Thin Films

Gold-dispersed BaTiO, thin films were prepared by the rf magnetron sputtering method. The atomic ratio of Ba to Ti in the films was varied and the effects on the linear and nonlinear optical properties were investigated. As the atomic ratio increased, the value of χ⁽³⁾/α₅₃₂ for the gold-dispersed BaTiO₃ thin films slightly increased. It was found that the increase in the value of χ⁽³⁾/α₅₃₂ is due mainly to a change in the crystalline state of the BaTiO₃ matrix. However, it was also found that the atomic ratio had a smaller effect on the value of χ⁽³⁾/α₅₃₂ than did the refractive index of the matrix.     

A study on concrete degradation during molten core/concrete interactions

A series of MCCI tests was performed in COTELS project at NUPEC to examine concrete degradation characteristics during MCCI with and without water addition onto the debris. Molten stainless steel or a mixture composed of UO₂, ZrO₂, Zr and stainless steel was slumped into a two-dimensional concrete trap, where volumetric decay heat generation was simulated by an induction heating technique. The results of dry MCCI tests implied that concrete ablation was dominated by melting of aggregates when the debris was crusted and cement was thermally weaker than aggregates. Without presence of stable crust, unmolten aggregates were possible to relocate upward due to the density difference from the debris. Concrete responses under a wet condition showed a tendency that water migrated into thermally degraded concrete. A preliminary water migration model was incorporated into COCO code for transient heat conduction. The prediction by COCO code agreed with the tendency of concrete thermal responses observed in the dry and wet MCCI tests.     

Graphical Identifiability Criteria for Total Effects in Studies with an Unobserved Response Variable

Consider a case where cause-effect relationships between variables can be described as a causal diagram and the corresponding Gaussian linear structural equation model. In order to identify total effects in studies with an unobserved response variable, this paper proposes graphical criteria for selecting both covariates and variables caused by the response variable. The results enable us not only to judge from the graph structure whether a total effect can be expressed through the observed covariances, but also to provide its closed-form expression in case where its answer is affirmative. The graphical criteria of this paper are helpful to infer total effects when it is difficult to observe a response variable.

     

Orientation-controlled,low-temperature plasma growth and applications of h-BN nanosheets

Nano Research - Dimensionality and orientation of hexagonal boron nitride (h-BN) nanosheets are promising to create and control their unique properties for diverse applications. However,...     

Preparation of gold/hydroxyapatite hybrids using natural fish scale template and their effective albumin interactions

The gold (Au) nanoparticles (NPs) with the diameter of 15–40?nm were successfully synthesized in the hierarchical hydroxyapatite (HAp) nanostructures of natural fish scale templates, which were carried out by the Au³⁺ ion chemisorption, reduction and calcination processes to form the AuNPs/HAp hybrids. The AuNPs size as well as the surface plasmon resonance (SPR) absorption maximum was preserved with the hybridization process. Moreover, the AuNPs/HAp hybrid nanostructures exhibited preferential protein adsorption behavior at the biological bovine serum albumin (Ab) concentration regions that correspond to be 1.5?μM in the cell culture medium and 15.1?μM in human blood, and the Ab adsorption equilibrium constant of AuNPs/HAp hybrid was higher than that of the HAp alone. The SPR absorption maxima of the Ab-adsorbed AuNPs/HAp fish scales were red-shifted as compared with those of the AuNPs/HAp fish scales. Therefore, we synthesized the AuNPs using the fish scale template to exhibit the preferential protein adsorption, which will be a great significance to research the AuNPs/HAp hybrid functions.     

Easy-to-use authoring system for Noh (Japanese traditional) dance animation and its evaluation

Noh is a genre of Japanese traditional theater, a kind of musical drama. Similar to other dance forms, Noh dance (shimai) can also be divided into small, discrete units of motion (shosa). Therefore, if we have a set of motion clips of motion units (shosa), we can synthesize Noh dance animation by composing them in a sequence based on the Noh dance notation (katatsuke). However, it is difficult for researchers and learners of Noh dance to utilize existing animation systems to create such animations. The purpose of this research is to develop an easy-to-use authoring system for Noh dance animation. In this paper, we introduce the design, implementation, and evaluation of our system. To solve the problems of existing animation systems, we employ our smart motion synthesis technique to compose motion units automatically. We improved the motion synthesis method by enhancing the algorithms for detecting body orientation and constraints between the foot and ground to handle Noh dance motions correctly. We classify motion units as either pattern units, which are specific forms of motion, represented as shot motion clips, or locomotion units, generated on the fly to denote movement towards a specific position or direction. To handle locomotion-type motion units, we implemented a module to generate walking motion based on a given path. We created several Noh dance animations using this system, which was evaluated through a series of experiments. We also conducted a user test to determine the usefulness of our system for learners of Noh dance.     

A new approach to catalytic coal gasification: The recovery and reuse of calcium using biomass derived crude vinegars

A new concept in catalytic coal gasification has been developed. The use of crude vinegars (CVs) derived from different lignocellulosic biomass resources is described for the recovery and reuse of calcium in coal gasification. Calcium introduced by impregnation with a CV solution produced a higher catalytic activity than calcium loaded by impregnation with an aqueous acetic acid solution. Furthermore, CVs were found to be capable of reclaiming calcium from gasification residue and of improving the catalytic activity of the indigenous crystalline calcite in bituminous coal as in situ catalyst.     

Calcium loading during the dewatering of wet biomass in kerosene and catalytic activity for subsequent char gasification

This paper describes a novel approach for upgrading biomass fuels with high water content for gasification, using an oil-slurry dewatering (OSD) process and wet coffee grounds (CG) as a feedstock. The point of novelty is that calcium loading is carried out during the dewatering of wet CG in kerosene. The present work is focused on characterizing the dispersion state of calcium and its catalytic activity for subsequent char gasification. XRD and CO₂ chemisorption techniques have been applied to access the crystallite characteristics of calcium species in OSD-upgraded CG samples and their derived chars. The results obtained show that, for calcium loadings lower than 3 wt%, calcium highly disperses into the CG matrix under dewatering condition, and its catalytic activity for char gasification is comparable to that obtained by impregnation with an aqueous solution of calcium acetate. The results conclude that the dewatering process can provide an effective and practical catalyst loading procedure for biomass fuels with high water content. On the other hand, calcium loadings higher than 3 wt% give raise to poor dispersion in terms of significant decrease in the external surface area of the catalyst, being no longer proportional to the catalytic activity for char gasification.