Keratin sponge: immobilization of lysozyme

A porous wool keratin sponge was used for immobilization of lysozyme, a model bioactive substance and was demonstrated to be a unique biomaterial in terms that the activity of lysozyme linked to the sponge through disulfide bond was gradually released, while lysozyme through thioether bond was stably maintained.     

Effect of non-genetically modified (non-GM) soy varieties on the measured value of GM soy by a quantitative PCR method

It is very important to examine the effect of non-genetically modified (non-GM) soy varieties, which constitute the matrix of the testing sample used to quantify GM soy (RRS), on the measured value of RRS by quantitative PCR methods. Therefore, we quantified the amount of RRS in powder-mixed samples containing 1 or 5% RRS prepared by using 10 different varieties of non-GM soy as the matrix. The results revealed that the measured values were not in agreement with the powder-mixing levels and that the extent of the difference depended on the variety of non-GM soy used as the matrix. The yields of DNA extracted differed among the soy varieties. On the other hand, analysis of DNA-mixed samples, that were prepared with the DNAs extracted from RRS and non-GM soy varieties, showed that the measured values of RRS were in agreement with the DNA-mixing levels. These results strongly suggest that the proportions of DNA derived from RRS and non-GM soy were not consistent with the powder-mixing ratio in the case of some non-GM soy varieties used as a matrix, resulting in the discrepancy between the measured values and the powder-mixing levels.     

Sequencing of a 23 kb fragment from Saccharomyces cerevisiae chromosome VI

Plasmid clone gapB and lambda phage clone 4682, which contain fragments of Saccharomyces cerevisiae chromosome VI, were analysed. A 23 kb sequence was determined and ten open reading frames (ORFs) were revealed. Among them, five ORFs were identical to five yeast genes (SEC4, MSH4, SPB4, DEG1 and NIC96), two were identical to transposable elements (TYA and TYB), one (gapBorfF003) was highly homologous to a yeast expressed sequence tag, and another (4682orfF002) was predicted to be a nuclear protein. Sequence data have been submitted to DDBJ/EMBL/GenBank data library under Accession Number D44604 (clone gapB) and D44600 (clone 4682), respectively.     

Nationwide monitoring of selected antibiotics: Distribution and sources of sulfonamides, trimethoprim, and macrolides in Japanese rivers

We report the results of a nationwide survey of commonly used human and veterinary antibiotics (7 sulfonamides, trimethoprim, and 4 macrolides) in 37 Japanese rivers. Concentrations of the sum of the 12 target antibiotics ranged from undetectable to 626 ng/L, with a median of 7.3 ng/L for the 37 rivers. Antibiotics concentrations were higher in urban rivers than in rural rivers and were correlated with those of molecular markers of sewage (crotamiton and carbamazepine). Macrolides were dominant over sulfonamides in urban rivers. Sulfonamides, especially sulfamethazine (used in animals), were dominant in a few rivers in whose catchment animal husbandry is active. However, these signals of veterinary antibiotics were overwhelmed by those of human antibiotics in lower reaches of most rivers. The analysis of the antibiotics in all 88 samples showed that the target antibiotics in Japanese rivers are derived mainly from urban sewage, even though larger amounts of antibiotics are used in livestock. Most of the livestock waste-derived antibiotics are unlikely to be readily discharged to surface waters.     

Simulation of removal of HCI gas in a spray dry tower

A mathematical model of the absorption of HCI gas in a spray dry tower has been proposed. The proposed model describes the mechanism of HCI removal talking into account atomized droplet size distribution and the change in the droplet state from “slurry droplet” to “dry particle”. It is found that the removal efficiency can be simulated by using the model with the constant mean diameter of droplet from the simulation results. Simulation results of the removal of HCI gas are in good agreement with the experimental data in a spray dry tower.     

Initiator‐fragment incorporation radical polymerization of ethylene glycol dimethacrylate in the presence of 1,1‐diphenylethylene: synthesis and characterization of soluble hyperbranched polymer nanoparticles

The polymerization of ethylene glycol dimethacrylate (EGDMA) as crosslinker was carried out at 70 and 80 °C in benzene using dimethyl 2,2′‐azobisisobutyrate (MAIB) as initiator at concentrations as high as 0.50–0.70 mol l^?1 in the presence of 1,1‐diphenylethylene (DPE), where the concentrations of EGDMA and DPE were 0.50–0.70 and 0.25–0.50 mol l^?1, respectively. The polymerization proceeded homogeneously, without gelation, to give soluble polymers. The yield and molecular weight of the resulting polymers increased with time. The homogeneous polymerization system involved ESR‐observable DPE‐derived radicals of considerably high concentration (3.6–5.3 × 10^?5 mol l^?1). The methoxycarbonylpropyl groups as MAIB‐fragments were incorporated as a main constituent (35–50 mol%) into the polymers (initiator‐fragment incorporation radical polymerization). The polymers also contained DPE units (15 mol%) and EGDMA units with double bonds (10–25 mol%) and without double bonds (20 mol%). Results from gel permeation chromatography (GPC)–multiangle laser light scattering (MALLS), transmission electron microscopy (TEM) and viscometric measurements revealed that the individual polymer molecules were formed as hyperbranched nanoparticles. Copyright © 2004 Society of Chemical Industry     

Formation of a soluble hyperbranched polymer via initiator–fragment incorporation radical copolymerization of divinyl adipate and isobutyl vinyl ether

The copolymerization of divinyl adipate (DVA) with isobutyl vinyl ether (IBVE) was conducted at 70 and 80 °C in benzene using azobisisobutyronitrile (AIBN), at a concentration as high as 0.50 mol l^?1 as the initiator, where the concentrations of DVA and IBVE were 0.40 and 0.60 mol l^?1, respectively. The copolymerization proceeded homogeneously, without any gelation, to yield soluble copolymers in spite of the high molar ratio of DVA as an excellent cross‐linker for IBVE. The copolymer yield increased with time, and the number‐average molecular weight (M_n = 0.9–2.4 × 10⁴ g mol^?1) from gel permeation chromatography (GPC) and molecular weight distribution (M_w/M_n = 1.5–7.6) of the resulting copolymer increased with copolymer yield. The cyanopropyl group, as a fragment of AIBN, was incorporated as a main constituent in the copolymer, the fraction of which increased from ca 10 to ca 20 % with copolymer yield, hence indicating that the copolymerization is an initiator–fragment incorporation radical polymerization. The copolymers also contained IBVE units (10–30 %) and DVA units with intact double bond (8–36 %) and without double bond (45 %). The intrinsic viscosity of the copolymer was very low (0.1 dl g^?1) at 30 °C in tetrahydrofuran. The results from GPC–multi‐angle laser light scattering (MALLS), transmission electron microscopy (TEM) and MALLS revealed that individual copolymer molecules were formed as hyperbranched nanoparticles. Copyright © 2004 Society of Chemical Industry     

纳米金涂料的研制与应用

用特殊的防凝结聚合物和一种温和的还原剂成功地生产出高浓度纳米金溶胶。胶的固相中纳米金的质量分数为80％（粒度为10～30nm）．其余固相为防凝结聚合物。可通过选择防凝结聚合物的极性、用某种溶剂按需要比率稀释溶胶。这类溶胶可应用到电子、光学、催化剂、颜料及金属涂料等各领域。