Removal of acetaldehyde vapor with impregnated activated carbons: effects of steric structure on impregnant and acidity

The acetaldehyde adsorption capacities of activated carbons impregnated with various amines were experimentally studied by using fixed beds. It was found that the adsorption capacity of impregnated activated carbons is influenced by the steric structure of impregnants as well as their acidity. For activated carbons impregnated with aromatic amines, ortho and meta substituents on the benzene ring hindered the condensation reaction with acetaldehyde. The activated carbon impregnated with aminobenzenesulfonic acids differed from that impregnated with the other amines in the acetaldehyde adsorption mechanism in that a Doebner-Miller reaction was involved. Also, aminobenzenesulfonic acids were not only the reactant but also the acid catalyst in the removal of acetaldehyde. Since p-aminobenzenesulfonic acid reacts with acetaldehyde without steric hindrance in the Doebner-Miller reaction, it is the most suitable impregnant for the chemisorption of acetaldehyde.     

Development of new dye-metal agarose-coated alumina matrix and elution strategy for purification of alcohol dehydrogenase

A high-density matrix was prepared by coating an alumina particle with agarose using an emulsion technique. Iminodiacetic acid and Cibacron Blue 3GA were immobilized onto this matrix. Charging this matrix with zinc created a useful chromatography matrix for purification of yeast alcohol dehydrogenase. The elution strategy was then investigated to obtain a high recovery of this enzyme and a high purification factor. One-step elution using 4 mM EDTA containing 0.5 M NaCl resulted in 66% enzyme recovery and a purification factor of 4.7. Two-step elution using imidazole containing NaCl resulted in a higher purification factor. The first-step elution using 5 mM imidazole containing 1 M NaCl released most contaminant proteins. The second-step elution using 150 mM imidazole containing 1.5 M NaCl resulted in high-performance purification with a purification factor of 6.5 and an enzyme recovery of 40.7%. Equilibration of the matrix with imidazole prior to sample application increased the purification factor and the enzyme recovery to 8.4 and 76.8%, respectively.     

Synthesis of carbon nanotubes on carbon fibers by means of two-step thermochemical vapor deposition

The present study aimed at development of a method for synthesizing multi-walled carbon nanotubes (CNTs) on carbon paper substrates (CP) at densities as high as those so far reported for CNTs formed on quartz substrates. Applying conditions optimized for CNTs synthesis on quartz substrates, in which CP was heated at 1073 K, being placed parallel to the flow of m-xylene/ferrocene vapor, resulted in formation of extremely few deposits on CP. Forced vapor flow through the CP greatly improved the frequency and homogeneity of deposition of the Fe-bearing nanoparticles, but these became encapsulated by carbon and deactivated. The addition of H₂S to the vapor further enhanced nanoparticle deposition. Moreover, it enabled the subsequent formation of CNTs at densities as high as 2-6 × 10⁹ cm⁻². In order to realize such high population densities, it was found essential to perform CVD in a two-stage sequence commencing with nanoparticles deposition at 1073 K followed by the formation and growth of CNTs at 1273 K, with the H₂S concentration in the vapor phase optimized throughout within a range of 0.014-0.034 vol%.     

Degradation of Azo Compounds by Aeromonas hydrophila var. 24B

A bacterium which has the ability to degrade azo dyes has been isolated from a polluted environment and identified as Aeromonas hydrophilia. The specificity of azo dyes to the bacterium was examined. p-Acetamidoazobenzene, p-aminoazobenzene, acetanilide, aniline and p-phenylenediamine, which are produced as metabolites, were also isolated.     

Effect of a body-tie structure fabricated by partial trench isolation on the suppression of floating body effect induced soft errors in SOI SRAM investigated using nuclear probes

Soft errors induced by proton, helium and oxygen ion irradiations were measured as a function of distance between a body electrode under partial trench isolation and a metal pad connected to a tungsten via for the first metal layer of a silicon-on-insulator (SOI) static random access memory. Abnormal drain charges induced by ion irradiations with various distances in the SOI metal oxide semiconductor field effect transistor were simulated to be compared with the experimental results. The soft errors were found to depend on the distance between the body electrode and the metal pad in the case of the abnormal drain charge, which is induced by incident ions, lower than the critical charge of the SRAM cells. The soft errors did not depend on the distance for the abnormal drain charges higher than the critical charge.     

Knockdown of RRM1 with Adenoviral shRNA Vectors to Inhibit Tumor Cell Viability and Increase Chemotherapeutic Sensitivity to Gemcitabine in Bladder Cancer Cells

RRM1—an important DNA replication/repair enzyme—is the primary molecular gemcitabine (GEM) target. High RRM1-expression associates with gemcitabine-resistance in various cancers and RRM1 inhibition may provide novel cancer treatment approaches. Our study elucidates how RRM1 inhibition affects cancer cell proliferation and influences gemcitabine-resistant bladder cancer cells. Of nine bladder cancer cell lines investigated, two RRM1 highly expressed cells, 253J and RT112, were selected for further experimentation. An RRM1-targeting shRNA was cloned into adenoviral vector, Ad-shRRM1. Gene and protein expression were investigated using real-time PCR and western blotting. Cell proliferation rate and chemotherapeutic sensitivity to GEM were assessed by MTT assay. A human tumor xenograft model was prepared by implanting RRM1 highly expressed tumors, derived from RT112 cells, in nude mice. Infection with Ad-shRRM1 effectively downregulated RRM1 expression, significantly inhibiting cell growth in both RRM1 highly expressed tumor cells. In vivo, Ad-shRRM1 treatment had pronounced antitumor effects against RRM1 highly expressed tumor xenografts (p < 0.05). Moreover, combination of Ad-shRRM1 and GEM inhibited cell proliferation in both cell lines significantly more than either treatment individually. Cancer gene therapy using anti-RRM1 shRNA has pronounced antitumor effects against RRM1 highly expressed tumors, and RRM1 inhibition specifically increases bladder cancer cell GEM-sensitivity. Ad-shRRM1/GEM combination therapy may offer new treatment options for patients with GEM-resistant bladder tumors.     

Dietary PlsEtn Ameliorates Colon Mucosa Inflammatory Stress and ACF in DMH-Induced Colon Carcinogenesis Mice: Protective Role of Vinyl Ether Linkage

Ethanolamine plasmalogen (PlsEtn), a sub-class of ethanolamine glycerophospholipids (EtnGpl), is a universal phospholipid in mammalian membranes. Several researchers are interested in the relationship between colon carcinogenesis and colon PlsEtn levels. Here, we evaluated the functional role of dietary purified EtnGpl from the ascidian muscle (87.3 mol% PlsEtn in EtnGpl) and porcine liver (7.2 mol% PlsEtn in EtnGpl) in 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in vivo, and elucidated the possible underlying mechanisms behind it. Dietary EtnGpl-suppressed DMH-induced aberrant crypt with one foci (AC1) and total ACF formation (P < 0.05). ACF suppression by dietary ascidian muscle EtnGpl was higher compared with dietary porcine liver EtnGpl. Additionally, dietary EtnGpl decreased DMH-induced oxidative damage, overproduction of TNF-α, and expression of apoptosis-related proteins in the colon mucosa. The effect of dietary ascidian muscle EtnGpl showed superiority compared with dietary porcine liver EtnGpl. Our results demonstrate the mechanisms by which dietary PlsEtn suppress ACF formation and apoptosis. Dietary PlsEtn attained this suppression by reducing colon inflammation and oxidative stress hence a reduction in DMH-induced intestinal impairment. These findings provide new insights about the functional role of dietary PlsEtn during colon carcinogenesis.     

Direct Spectroscopic Determination of Europium（ Ⅱ ） Concentration During Europium（ Ⅲ ） Electro-Reduction in Hydrochloric Acid Medium

Europiumis one of the most important rare earth(RE) element .It is widely used as a component ofcathode ray tubes , with screen coated with red phos-phor ,as phosphorescent pigments ,andinlaser optics .It can also be used as neutron-absorbing material .In…     

SELECTIVE UPTAKE OF CESIUM BY AMMONIUM TUNGSTOPHOSPHATE (AWP) - CALCIUM ALGINATE COMPOSITES

ABSTRACT

The fine crystals of ammonium tungstophosphate (AWP) exchanger were immobilized in the biopolymer consisting of calcium alginate (CaALG) gels. The uptake rate of Cs⁺ for the AWP-CaALG composite was fairly fast and the uptake percentage of Cs^? was above 90 % within 30 min even in the presence of 5 M HNO₃ In a wide HNO₃concentration region of 0.1 - 5 M, the distribution coefficient of Cs^? for the composite was about 10⁴ cm³/g, while those for other nuclides, Na⁺, Sr²⁺, Co²⁺, Eu³⁺ and Am³⁺, were less than 10 cm³/g. The uptake of Cs⁺ followed a Langmuir-type adsorption equation, and the maximum uptake capacity of Cs⁺ increased with the content of AWP immobilized in the composite. The trace amounts of ¹³⁷Cs in the presence of 5 M NaNO₃-l M HNO₃ were selectively adsorbed on the composite column. The AWP-CaALG composite proved to be effective for the selective removal of radioactive cesium from waste solutions containing HNO₃ and NaNO₃