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81.
Satoru Hommura Yasuhiro Kunisa Ichiro Terada Masaru Yoshitake 《Journal of fluorine chemistry》2003,120(2):151-155
Characteristics of fibril reinforced membranes developed by Asahi Glass Company are reviewed. PTFE-fibrils <1 μm in diameter are dispersed in ion-exchange membranes uniformly. Mechanical properties, such as tensile strength, tear strength, creep property and compressive property were examined and compared with non-reinforced membranes. Fibril reinforced membranes, even by the addition of a small amount of PTFE-fibrils (2.7 wt.%), show excellent mechanical strength, especially in creep and tear strength. Cell performance is nearly equal to the one using a non-reinforced membrane and cell voltage stays about the same during the cell operation at 80 °C for 3000 h. 相似文献
82.
Chetsumon Aparat Umeda Fusako Maeda Isamu Yagi Kiyohito Mizoguchi Tadashi Miura Yoshiharu 《Applied biochemistry and biotechnology》1998,(1):249-256
A photobioreactor was constructed using anchored polyurethane foam strips (1 x 1 x 40 cm) fixed onto a stainless-steel ring
to prevent flotation, as a biomass support material (BSM). This type of reactor was named a seaweed-type bioreactor. A filamentous
cyanobacterium, Scytonema sp. TISTR 8208, which produces a novel cyclic dodecapeptide antibiotic, was immobilized in seaweed-type
photobioreactor and cultivated with air containing 5% CO2 sparged at a gas flow rate of 250 mL/min under illumination at a light intensity of 200 μmol photon m-2s-1. The antibiotic produced in the seaweed-type photobioreactor was purified by HPLC and examined regarding its spectrum and
mode of action. The antibiotic effectively inhibited the growth of Gram-positive bacteria, pathogenic yeasts, and filamentous
fungi, but it had only a weak effect on Gram-negative bacteria. Scanning electron micrograph analysis showed that the most
characteristic change was swelling of the cells after exposure to the antibiotic. The antibiotic seems to alter the conformation
of the microbial cell membrane, thereby changing its permeability, leading to osmotic shock. 相似文献
83.
The bienzyme system consisting of glucose oxidase and gluconolactonase was investigated using a conventional diffusion-kinetics model for an enzyme-modified field-effect transistor (FET) to clarify the effect of gluconolactonase coimmobilization in a glucose oxidase membrane on the steady-state response amplitude of a glucose sensor based on a FET. The model includes spontaneous and enzymatic hydrolysis reactions of d-glucono-δ-lactone and it elucidated the following experimental results: a glucose sensor with a membrane (about 1 μm in thickness) coimmobilizing these enzymes showed a sufficient response amplitude, whereas without coimmobilization of gluconolactonase no detectable response was observed up to 3 mM glucose; and the response amplitude depended strongly on the amount of lactonase in the membrane. The model also predicted an optimum enzyme ratio for coimmobilization in a membrane. 相似文献
84.
Yasuhiro Morisaki 《Journal of organometallic chemistry》2004,689(16):2684-2689
Novel organometallic conjugated polymer containing (η6-arene)Cr(CO)3 and platinum in the main chain was synthesized by dehydrohalogenation coupling reaction of (η6-1,4-diethynylbenzene)tricarbonylchromium with trans-(PBu3)2PtCl2. The polymer was soluble in common organic solvents and has the number-average molecular weight of 31,000 by GPC analysis. The polymer exhibited an absorption peak derived from π-π∗ interaction at 358 nm in the UV-Vis spectrum, which showed a red shift of approximately 90 nm compared to that of the model compound. The photochemical ligand exchange reaction of the polymer was also investigated. 相似文献
85.
M. Seto Yu. Maeda T. Matsuyama H. Yamaoka H. Sakai S. Masubuchi S. Kazama 《Hyperfine Interactions》1992,68(1-4):213-216
A nonconjugated conducting polymer (1,4-rans-polyisoprene) at different iodine doping levels has been studied with the 27.7-keV Mössbauer resonance of129I. At the light doping level, almost all iodines are covalently bonding to the carbon atoms, breaking the double bonds of the main chain. At the medium doping level, other iodine species are found, which are idendified as anion species, l?, l 3 ? and l 3 ? .At the heavy doping level, polyiodide anions, l 3 ? and l 5 ? , increase as compared to the covalently bonding iodine atoms and addtionally molecular iodine l2 exists. 相似文献
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A rapid and sensitive high-performance liquid chromatographic method has been developed for the quantitative analysis of methylguanidine and guanidine in physiological fluids. These quanidino compounds are separated on a 6 x 0.23 cm cation-exchange column with 0.5 M sodium hydroxide solution. The guanidino compounds are detected with a fluorometer, which monitors the fluorescent guanidine derivatives produced by the reaction of the eluted constituents with 9,10-phenanthrenequinone. Sensitivity to sub-nanomole levels of methylguanidine and guanidine is demonstrated. The method was successfully applied to physiological fluids such as serum and cerebrospinal fluid from uremic patients. 相似文献
90.
Chip-to-world interface is a major issue in the field of microfluidics and its applications. We developed a plug and play microfluidic device composed of a fluid driving unit and a polymer chip containing microfluidic channels and reservoirs. The one and only connection of the device to the external world is a set of electric control lines for the driving unit. Just putting the reagents and samples onto the reservoirs, the chip can be operated for chemical or biochemical reaction and analysis. We demonstrate here that silicon-based micropumps embedded in the present device allow us to achieve flexible fluidic manipulations with minimum time delay and dead volume. 相似文献