Influence of ash composition on heavy metal emissions in ash melting process

Two kinds of fly ash, discharged in the combustion of either refused derived fuel (RDF) or car shredder dust (SD), were examined for the emission of heavy metals in melting process under oxidizing and reducing conditions. The residual fractions of heavy metal in slag were experimentally estimated. As a result, it was confirmed that several volatile heavy metals were readily emitted during melting process. The type of atmosphere provided for the melting process was found to affect the emission of some volatile metals in RDF ash, but not in SD ash. The emission of volatile heavy metals in RDF ash under oxidizing conditions was lower than under any other conditions in this study. The emission behavior of iron and heavy metals in RDF ash under reducing conditions was similar to that in SD ash. These facts indicated that phosphorous in RDF ash had the property of fixing the volatile metals in the slag only under oxidizing conditions. Then the mixture of SD ash with phosphorous oxide powder was also tested in a melting process, and the result was consistent with the above inference of the effect of phosphorous.     

Cholesterol and fatty acids profile of Brazilian commercial chicken giblets

This study was carried out to determine the chemical composition, cholesterol contents and fatty acids profile of Brazilian commercial chicken giblets. The analysis were performed in gizzard, liver and heart in natura and also in cooked gizzard, fried liver and roasted heart. Fat and cholesterol contents ranged from 0.88% and 72.68 mg/100 g, in cooked gizzard, to 22.19% and 213.18 mg/100 g, in roasted heart. As the fat content gets higher, so does the cholesterol content. Palmitic (C16:0) and stearic acids (C18:0) were the predominant saturated fatty acids (SFA). The C16:0 ranged from 6.39% in cooked gizzard to 18.51% in fried liver. The C18:0 level ranged from 6.62% in roasted heart to 19.19% in cooked gizzard. Linoleic acid (C18:2 omega 6) was the predominant polyunsaturated fatty acid (PUFA). The data revealed that the three different analysed giblets presented a good PUFA/SFA ratio, with values of 1.11, 1.14 and 1.40 for cooked gizzard, fried liver and roasted heart, respectively.     

Immobilization of glucose oxidase on nonwoven fabrics with bombyx mori silk fibroin gel

The enzyme glucose oxidase (GOD) was immobilized on the nonwoven fabrics, which have excellent properties in diffusivity of substrates, mechanical strength, and handling, with Bombyx mori silk fibroin gel. The nonwoven fabrics of silk fibroin, viscose rayon, poly-ethyleneterephthalate, 6-nylon, and polypropylene with activated surface by fluoline treatment were used. The stabilities of GOD to heat or pH changes were much improved by the immobilization as well as the case of the GOD immobilized in the silk fibroin membrane. Among nonwoven fabrics, silk fibroin was the most excellent support material for the immobilization of GOD although all nonwoven fabrics used here are able to be used as the support materials. The increase of the sensitivity was observed when the glucose sensor was made with the GOD immobilized on nonwoven silk fabrics as four times compared with the case of the GOD immobilized in the silk fibroin membrane.     

A 31P-NMR study of peroxo species formed during oxidation of cyclohexene with hydrogen peroxide in tri-n-butylphosphate catalyzed by heteropolyacids

In the oxidation of cyclohexene with H₂O₂in monophasic tri-n-butylphosphate (TBP) solution catalyzed by Keggin-type 12-heteropolyacids, i.e., H₃PMo_12-xW _x O₄₀(x=0–12), several peroxo species were observed by ³¹P-NMR spectroscopy in lower field than the original heteropolyacids. Their composition varied regularly with that of the starting catalyst. The P-containing peroxo species formed was deduced as [PM₄O₈(O₂)₈]^3-(M = Mo, W). The peroxo species formed more easily with a decrease in the W content, x of H₃PMo_12-xW_xO₄₀. It was further indicated from the reactivity with cyclohexene and the comparison with catalytic performance that W-rich peroxo species were catalytically more active than Mo-rich peroxo species for the oxidation of cyclohexene in this reaction system.     

Expression and stabilization of galactose oxidase in Escherichia coli by directed evolution

We have used directed evolution methods to express a fungalenzyme, galactose oxidase (GOase), in functional form in Escherichiacoli. The evolved enzymes retain the activity and substratespecificity of the native fungal oxidase, but are more thermostable,are expressed at a much higher level (up to 10.8 mg/l of purifiedGOase), and have reduced negative charge compared to wild type,all properties which are expected to facilitate applicationsand further evolution of the enzyme. Spectroscopic characterizationof the recombinant enzymes reveals a tyrosyl radical of comparablestability to the native GOase from Fusarium.     

Graded evolution of anisotropic microstructure during sintering from crystal-oriented powder compact

Anisotropic sintering, including shrinkage and grain growth, was examined for c-axis-oriented (Sr,Ca)₂NaNb₅O₁₅ (SCNN) ceramics, which were prepared by colloidal processing under a magnetic field. In the c-axis-oriented SCNN powder compact, shrinkage and grain growth along the c-axis were higher than those along the a-axis. The anisotropic microstructural development was clearly associated with anisotropic sintering shrinkage. X-ray diffraction, scanning electron microscopy, and energy back scattering diffraction showed that the grain growth of oriented particles by including random grains contribute to the development of the oriented microstructure. Finally, the highly crystal-oriented SCNN ceramics with a densified microstructure were obtained through anisotropic sintering. These results clearly showed the potential to develop a well-defined anisotropic microstructure during sintering by designing and controlling the particle packing structure in a powder compact.     

Star-shaped poly(lactic acid) with carboxylic acid terminal groups via poly-condensation

A series of star-shaped poly(lactic acid)s with carboxylic acid terminal groups have been synthesized by direct poly-condensation of lactic acid in the presence of a poly-carboxylic acid core molecule with triphenylphosphonium trifluoromethanesulfonate (TPP-T) catalyst.These star-polymers had thermal properties not very much different from those of star-shaped poly(lactic acid) with hydroxyl terminal groups and linear poly(lactic acid), irrespective of the structure of the core molecule and number of polymer arms. Solubility and degradability of these star-polymers were, however, greatly enhanced compared to those of star-polymers with hydroxyl terminal groups and increased depending on the number of polymer arms. From the star-shaped polymers, a variety of ammonium salts and the corresponding carboxyamides were successfully prepared.     

Structurally Diverse Polyamines: Solid‐Phase Synthesis and Interaction with DNA

A versatile solid‐phase approach based on peptide chemistry was used to construct four classes of structurally diverse polyamines with modified backbones: linear, partially constrained, branched, and cyclic. Their effects on DNA duplex stability and structure were examined. The polyamines showed distinct activities, thus highlighting the importance of polyamine backbone structure. Interestingly, the rank order of polyamine ability for DNA compaction was different to that for their effects on circular dichroism and melting temperature, thus indicating that these polyamines have distinct effects on secondary and higher‐order structures of DNA.