Near-infrared spectroscopic study of the physical and mechanical properties of wood with meso- and micro-scale anatomical observation

Estimation of the density along with the tensile strength of wood within both the elastic and plastic deformation ranges, represented as modulus of elasticity (MOE) and ultimate tensile stress (UTS), respectively, were performed using near-infrared (NIR) spectroscopy. A partial least squares (PLS) analysis was applied to the measurements of density, MOE, and UTS, and resulted in a high accuracy of prediction, independent of wood species. The correlation coefficient between the NIR spectra and criterion variables, and the regression vector resulting from the PLS analysis, suggested that the characteristic absorption bands were strongly related to the predictability of each property. In the case of softwood, absorption bands due to intra-molecular hydrogen-bonded OH groups in the crystalline regions of cellulose, which are oriented preferentially in a direction parallel to the cellulose chain, might strongly affect the tensile strength of softwood. Hardwoods have much more complex and variable structures than softwoods; therefore, it was supposed that the key factor governing the tensile strength in hardwood would be the interaction between the three principal constituents (i. e., cellulose, hemicellulose, and lignin) of wood.     

A machine discovery from amino acid sequences by decision trees over regular patterns

This paper describes a machine learning system that discovered a “negative motif”, in transmembrane domain identification from amino acid sequences, and reports its experiments on protein data using PIR database. We introduce a decision tree whose nodes are labeled with regular patterns. As a hypothesis, the system produces such a decision tree for a small number of randomly chosen positive and negative examples from PIR. Experiments show that our system finds reasonable hypotheses very successfully. As a theoretical foundation, we show that the class of languages defined by decesion trees of depth at mostd overk-variable regular patterns is polynomial-time learnable in the sense of probably approximately correct (PAC) learning for any fixedd, k≥0.     

A conceptual design of light ion beam fusion reactor—UTLIF(1)

UTLIF(1) is a conceptual design study on a light ion beam driven fusion reactor based on a concept of pin-bundle blanket. The study includes nuclear and structural analyses of the blanket, consideration on materials, tritium handling system and power conversion system designs, pellet and beam driver designs, and economic analysis of the plant. The pin-bundle blanket has been shown to be attractive for light ion beam fusion reactors. Some subjects to be developed have been pointed out from reactor engineering aspects.     

Basic study of photochemistry for application to advanced nuclear fuel cycle technology

In this study, we have accomplished for the first time the photochemical valence adjustment of Pu and Np for the separation and coextraction of these elements in a nitric acid solution using UV light irradiation. Also, the separation and coextraction of Pu and Np were substantiated in principle by the solvent extraction using 30% TBP/n-dodecone after or during the photochemical valence adjustment. By only one photochemical separation operation, about 86% of Pu and about 99% of Np were distributed into the organic phase and the aqueous phase, respectively, and then by only one photochemical coextraction operation, about 86% of Pu was distributed together with about 99% of Np into the same organic phase. Based on these experimental data, we determined that the photochemical oxidation reaction was due to the photoexcted nitric acid species, ′NO₃⁻.

To confirm the strong oxidative ability of this species, the photochemical dissolution tests of UO₂ powder in a nitric acid solution by UV light irradiation were carried out. The irradiation rate and the concentration of nitric acid solution significantly effects the photochemical dissolution reaction, we have also accomplished for the first time the photochemical dissolution of UO₂ at room temperature.     

Facial organization blocks access to low-level features: An object inferiority effect.

The current study investigated the influence of a low-level local feature (curvature) and a high-level emergent feature (facial expression) on rapid search. These features distinguished the target from the distractors and were presented either alone or together. Stimuli were triplets of up and down arcs organized to form meaningless patterns or schematic faces. In the feature search, the target had the only down arc in the display. In the conjunction search, the target was a unique combination of up and down arcs. When triplets depicted faces, the target was also the only smiling face among frowning faces. The face-level feature facilitated the conjunction search but, surprisingly, slowed the feature search. These results demonstrated that an object inferiority effect could occur even when the emergent feature was useful in the search. Rapid search processes appear to operate only on high-level representations even when low-level features would be more efficient. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Kinetics of the dissolution of scheelite in aqueous Na4EDTA solutions

The reaction kinetics of the dissolution of pure scheelite (CaWO₄) particles in aqueous Na₄EDTA solutions were studied at atmospheric pressure. As expected, the dissolution rate increased with decreasing initial particle size and with increasing temperature and Na₄EDTA concentration. Further, the dissolution rate decreased as the initial solid-liquid ratio and the ionic strength of the solution were increased. The experimental results do not support the conventional shrinking-core model for a single irreversible reaction. A new shrinking-core model for multiple reactions, composed of a noninstantaneous reversible reaction (scheelite dissociation into the ions Ca²⁺ and WO ₄ ²⁻ ) and an instantaneous irreversible reaction (formation of Ca-EDTA complex), was presented. The observed dependency of the dissolution rate on the relevant operating variables was the same a the theoretical predictions based on the present shrinking-core model. The activation energy was 49800 J mol⁻¹. These findings justify the validity of the assumed kinetic model with the multiple reactions as the rate-controlling step. The dissolution rate expression was obtained as a function of the initial particle size, initial solid-liquid ratio, Na₄EDTA concentration, temperature, and ionic strength of the solution.     

Conduction paths in sintered ionic conductive material Na1+xYxZr2−x(PO4)3

A NASICON type ionic conductor was synthesized. The ionic conduction paths for its ceramics were examined and interpreted by a simple equivalent circuit. It is recognized that two kinds of grain boundaries exist, which play as blocking element and high diffusive path, respectively. The grain boundaries in this ceramics dominate the total conductivity.     

Electroinduced aldol condensation

Passing a catalytic amount of electricity (7.5 × 10^?3 F mol^?1) into solution of aldehydes in DMF leads to formation of α, β-unsaturated carbonyl compounds through the aldol-type condensation with extremely high current efficiency (1 × 10⁴%).