卧式振动沸腾床旧砂冷却的计算机数字模拟

本文建立了新的卧式振动沸腾床旧砂冷却系统的数学模型,并进行了计算机数字模拟。通过模拟,研究了几个工艺参数对旧砂冷却的影响,并应用能耗指数E和冷却效率η对工厂中使用的旧砂冷却装置进行了评价。     

Adsorption of bovine serum albumin to a polymer brush prepared by atom-transfer radical polymerization in a porous inorganic membrane

Protein adsorption was performed by a polymer brush prepared by atom-transfer radical polymerization (ATRP) to a porous inorganic membrane. The porous inorganic membrane, Shirasu Porous Glass made from silica, was modified with a halogen-containing compound to bind the active species for the polymerization. Glycidyl methacrylate was polymerized from the halogen compound by ATRP for a prescribed time, and subsequently chemically modified. The progression of the chemical modification allowed the membrane to lower the phosphate-buffer flux of the porous membrane due to the attachment of the polymer brush. Bovine serum albumin (BSA), as a model protein, was adsorbed at 12 mg per gram of the membrane in permeating BSA solution through the polymer-brush-attached porous membrane.     

Electrolytic removal of ammonia from brine wastewater: scale‐up,operation and pilot‐scale evaluation

Brine wastewater with a high ammonia content from an iodine processing plant (commonly called kansui in Japan) was treated by electrolysis. The system, which can be considered as an indirect electrolytic treatment process, generates chlorine at the anodes and initiates the formation of mixed oxidants like hypochlorous acid. The oxidants then act as agents for ammonia destruction. Laboratory‐scale experiments showed that high ammonia concentrations (as much as 200 mg dm^?3) could be completely removed within a few minutes, and could be considered a good alternative for efficient ammonia removal from saline wastewaters. From laboratory‐scale experiments in the batch and continuous modes, the charge dose was analyzed and used as the operating and scale‐up factor. The value of the charge dose was not severely affected by changes in operating conditions such as electrode spacing and temperature. The charge dose from batch and continuous runs was found to be in the range of 23 C (mg NH₄‐N removed)^?1 to 29 C (mg NH₄‐N removed)^?1. Using the charge dose obtained from laboratory‐scale continuous electrolysis experiments as the scale‐up factor, a pilot‐scale reactor was designed, and the operating conditions were calculated. In the pilot‐scale reactor tests at different flow rates, the effluent ammonia concentrations were reasonably close to the calculated values predicted from the charge dose equation. Copyright © 2004 Society of Chemical Industry     

Isolated Schwann cells can synthesize the basement membrane in vivo

The purpose of the present study is to examine whether isolated Schwann cells that are not in contact with axons can synthesize the basement membrane in vivo. Schwann cells obtained from sciatic nerve of neonate Wistar rats were prepared in culture, harvested, and mixed with collagen matrix. The silicone tube filled with the collagen matrix containing Schwann cells was closed by a Millipore membrane at both ends to isolate the interior from the outer environment and was implanted in a gap between proximal and distal stumps of transected sciatic nerve of an adult Wistar rat. Ten days later, the implanted silicone tube was prepared for electron microscopic observations. Schwann cells in the tube were elongated longitudinally and lined up parallel to the proximo-distal direction. No regenerating axons penetrated the Millipore membrane into the tube. The basement membrane showing almost normal structure was produced on the surface of the Schwann cells. While the silicone tube was placed side by side to the intact sciatic nerve, Schwann cells in the tube were scattered and no basement membrane was observed. These results suggest that some humoral factors might be released from the transected nerve stumps, which may be responsible for the regular arrangement and the basement membrane formation by Schwann cells without any contact with axons.     

Poly[(R)-3-hydroxybutyrate] formation in Escherichia coli from glucose through an enoyl-CoA hydratase-mediated pathway

In this study, a new metabolic pathway for the synthesis of poly[(R)-3-hydroxybutyrate] [P(3HB)] was constructed in a recombinant Escherichia coli strain that utilized forward and reverse reactions catalyzed by two substrate-specific enoyl-CoA hydratases, R-hydratase (PhaJ) and S-hydratase (FadB), to epimerize (S)-3HB-CoA to (R)-3HB-CoA via a crotonyl-CoA intermediate. The R-hydratase gene (phaJ(Ac)) from Aeromonas caviae was coexpressed with the PHA synthase gene (phaC(Re)) and 3-ketothiolase gene (phaA(Re)) from Ralstonia eutropha in fadR mutant E. coli strains (CAG18497 and LS5218), which had constitutive levels of the beta-oxidation multienzyme FadB(Ec). When grown on glucose as the sole carbon source, the cells accumulated P(3HB) up to an amount 6.5 wt% of the dry cell weight, whereas the control cells without phaJ(Ac) or fadR mutation accumulated significantly smaller amounts of P(3HB). These results suggest that PhaJ(Ac) and FadB(Ec) played an important role in supplying monomers for P(3HB) synthesis in the pathway. Furthermore, by using this pathway, a P(3HB)-concentration-dependent fluorescent staining screening technique was developed to rapidly identify cells that possess active R-hydratase.     

Syntheses of alpha-arbutin-alpha-glycosides and their inhibitory effects on human tyrosinase

Alpha-arbutin is a tyrosinase inhibitor. We synthesized alpha-arbutin-alpha-glycosides by the transglycosylation reaction of cyclomaltodextrin glucanotransferase from Bacillus macerans using alpha-arbutin and starch as acceptor and donor molecules, respectively. We isolated and characterized two major products from the reaction mixture. The structural analyses using 13C- and 1H-NMR spectroscopy proved that they were 4-hydroxyphenyl alpha-maltoside (alpha-Ab-alpha-G1) and 4-hydroxyphenyl alpha-maltotrioside (alpha-Ab-alpha-G2). Both alpha-Ab-alpha-G1 and alpha-Ab-alpha-G2 exhibited competitive-type inhibition on human tyrosinase as alpha-arbutin does. Their K(i) values were calculated to be 0.6 mM and 2.8 mM, respectively, which is slightly and significantly higher than that of alpha-arbutin (0.2 mM).     

Effects of Fruiting Bodies of Basidiomycetes on Yeast Growth Rates

The effects of edible fruiting of Basidiomycetes on growth of Saccharomyces cerevisiae and other yeast strains were examined. The growth rates were significantly increased in the presence of fruiting bodies but there was no significant difference growth yield between cultures with and without fruiting bodies. Growth rates of yeast cells were promoted in both synthetic and natural media.     

The tomato DWARF enzyme catalyses C-6 oxidation in brassinosteroid biosynthesis

Brassinosteroids (BRs) are steroidal plant hormones essential for normal plant growth and development. Mutants in the biosynthesis or perception of BRs are usually dwarf. The tomato Dwarf gene (D), which was predicted to encode a cytochrome P450 enzyme (P450) with homology to other P450s involved in BR biosynthesis, was cloned previously. Here, we show that DWARF catalyses the C-6 oxidation of 6-deoxocastasterone (6-deoxoCS) to castasterone (CS), the immediate precursor of brassinolide. To do this, we first confirmed that the D cDNA complemented the mutant light- and dark-grown phenotypes of the extreme dwarf (dx) allele of tomato. To identify a substrate for the DWARF enzyme, exogenous application of BR intermediates to dx plants was carried out. C-6 oxoBR intermediates enhanced hypocotyl elongation whereas the C-6 deoxoBR, 6-deoxoCS, had little effect. Quantitative analysis of endogenous BR levels in tomato showed mainly the presence of 6-deoxoBRs. Furthermore, dx plants were found to lack CS and had a high level of 6-deoxoCS in comparison to D plants that had CS and a lower level of 6-deoxoCS. Confirmation that DWARF catalyzed the C-6 oxidation of 6-deoxoCS to CS was obtained by functional expression of DWARF in yeast. In these experiments, the intermediate 6alpha-hydroxycastasterone was identified, indicating that DWARF catalyzes two steps in BR biosynthesis. These data show that DWARF is involved in the C-6 oxidation in BR biosynthesis.     

茅台酒美

茅台酒美,天下同醉.茅台酒美,美在历史、美在文化、美在品质、美在环境；多彩贵州,彩在“茅台”；多美贵州,美在“茅台”.     

Heat transfer characteristics of a reservoir embedded loop heat pipe (Heat transfer characteristics of a deployable radiator for use on the ETS‐VIII satellite while in orbit)

As heat generation in satellites increases, ensuring that they are provided with sufficient radiator panel area is an important problem. Deployable radiators, with radiator panels that are deployed post‐launch in space to increase the satellite's effective radiator panel area of the satellite, are becoming an important thermal control technology. A reservoir embedded loop heat pipe (RELHP) is used in deployable radiators as a heat transport device. A deployable radiator of this type was mounted on the ETS‐VIII satellite, which was launched on December 18, 2006 and injected into a geostationary orbit. The satellite is still operating without any significant issues over two years later. This paper investigates the heat transport characteristics of an RELHP system used in a deployable radiator in a geostationary orbital environment. This system can be successfully started up in a micro gravity environment. We also found that the sub‐cooling region is shorter in a micro gravity environment than in a terrestrial gravity environment, because there is less heat leakage into the reservoir in a micro gravity environment. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20346