Estimation of Δf of nitro derivatives of benzene and toluene using AM1 and DSC

Abstract

The AM1 molecular orbital method and reduced pressure differential scanning calorimetry(RP-DSC) were applied to nitro derivatives of benzene and toluene for estimating Δ_f(1) and Δ_f(c). The heats of phase change were determined by RP-DSC with moderate accuracy and the combination of the heats and Δ_f(g) estimated by AM1 gave Δ_f in condensed phases which are similar to those found in literatures.     

Simulation of Demolition of Reinforeced Concrete Buildings by Controlled Explosion

Abstract: A system for simulating the behavior of a reinforced concrete building being demolished by controlled explosion is developed. The purpose for developing the system is to examine the effects of blast location, blast size, blast sequence, delay time of blasts and other factors on a planning of blast demolition. It consists of a numerical analysis part to simulate the blast demolition of a space-framed structure and a visualizing system to show the dynamic behavior obtained from the numerical analysis. The numerical analysis is based on the distinct element method, which is improved for consideration of the bending behavior of beams and columns. The elastoplastic behavior of the structural members up to the collapse are modeled in the analysis. The numerical data display system 'AVS' is employed, in addition to the computer code developed by the authors, to make the visualization system for three-dimensional dynamic problems. In this report the method of numerical analysis, the visualizing system, and a comparison between the experiment and analysis are presented.     

Modeling high adsorption capacity and kinetics of organic macromolecules on super-powdered activated carbon

The capacity to adsorb natural organic matter (NOM) and polystyrene sulfonates (PSSs) on small particle-size activated carbon (super-powdered activated carbon, SPAC) is higher than that on larger particle-size activated carbon (powdered-activated carbon, PAC). Increased adsorption capacity is likely attributable to the larger external surface area because the NOM and PSS molecules do not completely penetrate the adsorbent particle; they preferentially adsorb near the outer surface of the particle. In this study, we propose a new isotherm equation, the Shell Adsorption Model (SAM), to explain the higher adsorption capacity on smaller adsorbent particles and to describe quantitatively adsorption isotherms of activated carbons of different particle sizes: PAC and SPAC. The SAM was verified with the experimental data of PSS adsorption kinetics as well as equilibrium. SAM successfully characterized PSS adsorption isotherm data for SPACs and PAC simultaneously with the same model parameters. When SAM was incorporated into an adsorption kinetic model, kinetic decay curves for PSSs adsorbing onto activated carbons of different particle sizes could be simultaneously described with a single kinetics parameter value. On the other hand, when SAM was not incorporated into such an adsorption kinetic model and instead isotherms were described by the Freundlich model, the kinetic decay curves were not well described. The success of the SAM further supports the adsorption mechanism of PSSs preferentially adsorbing near the outer surface of activated carbon particles.     

Profiles of lipid components,fatty acid distributions of triacylglycerols and phospholipids in Jack beans (Canavalia gladiata DC.)

Endogenous tocopherols in extracted lipids from Jack beans (Canavalia gladiata DC.) were determined by high-performance liquid chromatography (HPLC), and were investigated in relation to the fatty acids (FA) distribution of triacylgycerols (TAG) and phospholipids (PL). The dominant tocopherols were (δ)-tocopherol (78.9–96.5 mg%) and (γ)-tocopherol (42.1–56.1 mg%) with much smaller amounts of (α)-tocopherol (1.1–1.3 mg%). The lipids of Jack beans comprised mainly TAG (34.6–38.6 wt.%) and PL (54.8–57.4 wt.%), and other components were also detected in minor proportions (0.3–3.8 wt.%). The PL components included phosphatidyl choline (46.2–48.7 wt.%), phosphatidyl inositol (23.4–29.6 wt.%) and phosphatidyl ethanolamine (18.5–21.2 wt.%). Comparison of these different beans showed, with a few exceptions, no significant differences (P > 0.05) in FA distribution. The FA distribution of TAG among the five beans was evident in the Jack beans: unsaturated FA (93.3–95.3 wt.%) were predominantly concentrated at the sn-2 position and saturated FA (33.6–34.4wt.%) primarily occupying the sn-1 position or sn-3 position. The results obtained from this work would provide useful information to both producers and consumers for manufacturing functional foods or beverages in Japan and elsewhere.     

Thermal studies of wood impregnated with ZnCl<Subscript>2</Subscript>

In this work the thermal behavior of wood impregnated with ZnCl₂ is studied. Impregnation of wood with ZnCl₂ is a treatment used in activated carbon production, and liquefaction and fast pyrolysis of biomass. Frequently, the impregnated wood is dried for several hours at temperatures above 370 K and then it is carbonized. Catalytic pyrolysis occurs, giving rise to a complex set of reactions. A TG/DTA study was done on the raw material, the activated carbon, the pure ZnCl₂ and the intermediate products in order to study the mass and thermal changes occurring. Elemental analysis and SEM analysis were also carried out. An exothermic torrefaction develops during the drying step; the torrefied product is carbonized in an endothermic process that involves ZnCl₂ volatilization. The washed impregnated wood carbonizes through an exothermic process that may involve the decomposition of cellulose, lignin and the solid product of hemicellulose torrefaction.     

Identification of bottom-fermenting yeast genes expressed during lager beer fermentation

It has been proposed that bottom-fermenting yeast strains of Saccharomyces pastorianus possess at least two types of genomes. Sequences of genes of one genome [S. cerevisiae (Sc)-type] have been found to be highly homologous (more than 90% identity) to S. cerevisiae S288C sequences, while those of the other [Lager (Lg)-type] are less so. To identify and discriminate Lg-type from Sc-type genes expressed during lager beer fermentation, normalized cDNA libraries were constructed and analysed. From approximately 22 000 ESTs, 3892 Sc-type and 2695 Lg-type ORFs were identified. Expression patterns of Sc- and Lg-type genes did not correlate with particular cell functions in KEGG classification system. Moreover, 405 independent clones were isolated that have no significant homology with sequences in the S288C database, suggesting that they include the bottom-fermenting yeast-specific (BFY) genes. Most of BFY genes have significant homology with the S. bayanus genome.