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  • 1
    Electronic Resource
    Electronic Resource
    Determination of inorganic phosphorus using immobilized pyruvate oxidase (1983)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 25 (1983), S. 3013-3026 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A new method for the automated analysis of inorganic phosphorus using immobilized enzyme was established. The method was based on the determination of hydrogen peroxide formed by the action of pyruvate oxidase on inorganic phosphate and pyruvate. Since pyruvate oxidase required inorganic phosphate for its stability and therefore had to be kept in a buffer containing inorganic phosphate, it could hardly be used as a reagent in the form of aqueous solution for the determination of inorganic phosphorus. This difficulty was overcome by using immobilized pyruvate oxidase in column form. When the present method was applied to the determination of inorganic phosphorus in serum, it gave perfect linearity of the data up to 0.20 g inorganic phosphorus/L with satisfactory precision, reproducibility, high sensitivity, and accurate recoveries. The immobilized enzyme reactor unit showed enhanced heat stability and good operational stability for a one-month period, during which time it was used over 900 times for analyses. The enzyme column was not affected by organic phosphorus compounds. The results correlated satisfactorily with those obtained by another well-established method.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260251217
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  • 2
    Electronic Resource
    Electronic Resource
    Polymerization of ethylene and propylene initiated by milled alumina powder (1980)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 25 (1980), S. 1209-1216 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Generation of free radicals (mechano-radicals) by the milling of alumina powder at 77 K was demonstrated by ESR. After milling of alumina in the presence of ethylene (simultaneous milling) at 77 K, polyethylene-propagating radicals instead of the alumina mechano-radicals were detected by ESR. Also the contact of ethylene with the milled alumina converted alumina mechano-radicals into polyethylene propagating radicals at a temperature above the melting point of ethylene. The products extracted by hot toluene from the simultaneous milling were identified by IR to be polyethylene, and their molecular weights were roughly 10,000. The residues after the extraction were bonded with the alumina. Polypropylene was also produced by a similar method of milling of alumina in the presence of propylene. The obtained polyproylene was atactic, and its molecular weight was about 400.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1980.070250622
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  • 3
    Electronic Resource
    Electronic Resource
    Polymerizations of ethylene and propylene initiated by milled metallic oxides. II. Characterizations of the mechanochemically produced polymers (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 291-298 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Polyethylene was mechanochemically produced by milling of alumina powder at room temperature in the presence of ethylene monomer. Nearly 50% of the produced polyethylene was chemically bonded with the matrix of the alumina. The other 50% of the polymer was extracted by the organic solvents. The polyethylene extracted by the hot n-heptane was characterized as having a structure similar to that of the branched polyethylene of low density, and the toluene extracted polyethylene had a structure similar to that of the high density polyethylene. The molecular weights of the mechanochemically produced polyethylene were found to distribute from 102 to 106 by gel permeation chromatography. The weight average molecular weight was estimated as 260,000 after the 3 days milling. Mechanochemical polymerization of ethylene was also demonstrated by milling of silica in the presence of ethylene monomer. Polymerization of propylene by milling of alumina under propylene atmosphere was performed. The obtained polymer was found to be an atactic by IR measurement and the molecular weight of the extracted product was determined as ≃ 400 by the vapor pressure osmometer.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070290127
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  • 4
    Electronic Resource
    Electronic Resource
    1H-NMR and UV studies of Rh complexes as a stereoregular polymerization catalysts for phenylacetylenes: Effects of ligands and solvents on its catalyst activity (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 32 (1994), S. 1113-1120 
    Details
    ISSN: 0887-624X
    Keywords: phenylacetylene ; stereoregular polymerization ; Rh complex catalyst ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phenylacetylene and its homologues bearing methoxy or chloro groups in the para position of the phenyl ring were stereoregularly polymerized by Rh complex catalysts, e.g., [Rh (norbornadiene) Cl]2, in the presence of various solvents. The 1H-NMR and UV study of the Rh complex showed that the activity of the Rh catalysts greatly depends upon not only the ligand in the Rh catalyst but also on the solvent used, e.g., polyphenylacetylene with a highly cis-transoidal content was quantitatively obtained when norbornadiene was coordinated as the ligand, and triethylamine (TEA) was used as solvent, whereas tetrahydrofuran (THF) and benzene reduced the cis content. It was also found that the Rh catalyst as a dimer complex dissociates into the monomeric species not only when TEA was used but also when alcohol, benzene, and THF were used. The resulting monomeric species was considered as the important propagation species in this polymerization. The sharp line width observed in the 1H-NMR spectrum of polyphenylacetylene and its homologues which were prepared in ethanol or TEA was interpreted by the narrow chemical shift distribution arising from the high cis content. © 1994 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1994.080320613
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  • 5
    Electronic Resource
    Electronic Resource
    Pressure-induced cis to trans isomerization of aromatic polyacetylenes prepared using a Rh complex catalyst: A control of π-conjugation length (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 217-223 
    Details
    ISSN: 0887-624X
    Keywords: aromatic polyacetylene ; Rh complex catalyst ; cis-transoid ; pressure ; isomerization ; solitons ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: This study reports that stereospecific polymerization of aromatic acetylenes, e.g., p-methoxyphenylacetylene (pMOPA) and p-ethoxyphenylacetylene (pEOPA)was successfully performed to give polyacetylene selectively bearing cis-transoid forms in high yield when a Rh complex catalyst, [Rh(norbornadiene)Cl]2 was used in the presence of triethylamine as the polymerization solvent together with a detailed characterization of the resulting polymers, before and after compression. Compression of these polymers induced a cis-trans isomerization at room temperature under vacuum even in the solid state. Based on data collected before and after compression it is estimated that the trans conjugated length, (C=C)n, produced as a result of the compression is n = 26 for PpMOPA and n = 40 for PpEOPA polymers, respectively. We further found that g values in the ESR spectra of the pristine polymer were shifted to higher magnetic field by compression, indicating that unpaired electrons called solitons are stabilized in the trans conjugation length as mobile electrons, although in the pristine polymers the unpaired electrons are stabilized in the less conjugated chain, showing large g value, suggesting a magnetic interaction between oxygen in the alkoxy group of phenyl moiety and unpaired electrons in the cis form. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 217-223, 1998
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Unusually facil cis to trans isomerization of a polypropiolate bearing a long alkyl chain polymerized using a [Rh(norbornadiene)Cl]2 catalyst: An ESR study (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2457-2461 
    Details
    ISSN: 0887-624X
    Keywords: polyalkylpropiolate ; Rh complex catalyst ; isomerization ; ESR ; soliton ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alkylpropiolate having n-hexadecyl moiety in the ester group was stereospecifically polymerized with a [Rh(norbornadiene)Cl]2 complex catalyst in alcohol to give rise to cis-transoid polyacetylenes in high yields. The unusually facile cis to trans isomerization for the polymer was found to be induced when the polymer was warmed to even less than ca. 57°C. Under these conditions ESR spectra bearing hyperfine structures due to the radicals generated by the rotational scission in the cis-π bond were observed. This isomerization induced a large g value shift in the ESR spectra together with an increase of the radical concentration during the isomerization, indicating formation of planar conjugated trans sequences that stabilize mobile unpaired electrons as solitons. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2457-2461, 1998
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Synthesis, geometric structure, and properties of poly(phenylacetylenes) with bulky para-substituents (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 3157-3163 
    Details
    ISSN: 0887-624X
    Keywords: poly(phenylacetylene) ; transition metal catalyst ; metathesis polymerization ; geometric structure ; gas permeability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phenylacetylenes (PAs) with bulky substituents (adamantyl, tert-butyl, and n-butyl groups) at the para-position polymerized in good yields with Fe, Rh, Mo, and W catalysts. The formed polymers were soluble, and their number-average molecular weights were in the range of thousands to hundred thousands. Whereas it is known that the poly(PA) obtained with the Fe catalyst is an insoluble cis-cisoidal polymer, the present polymers formed with the same catalyst were totally soluble in many solvents such as benzene and CHCl3. The 1H- and 13C-NMR and DSC data revealed that both of the polymers formed with the Fe and Rh catalysts had virtually all-cis structures, while those with the Mo and W catalysts had cis-rich and trans-rich structures, respectively. Cis-cisoidal and cis-transoidal structures of para-substituted poly(PAs) could not be distinguished because of their good solubility. The bulky substituents raised the temperature of cis-trans isomerization and improved the thermal stability of the polymers. Poly(p-t-BuPA) showed gas permeability higher than that of poly(PA). © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3157-3163, 1998
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    A chemiluminometric method for NADPH and NADH using a two-enzyme bioreactor and its application to the determination of magnesium in serumThe initial part of this work was presented at the 27th Annual Meeting of the Japanese Clinical Chemistry Society November 1987, Tokyo (Tabata et al., 1987). This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture, Japan. (1990)
    New York, NY : Wiley-Blackwell
    Biomedical Chromatography 4 (1990), S. 123-127 
    Details
    ISSN: 0269-3879
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Chemiluminometric methods are described for the automated flow injection analysis of NADPH and NADH using an immobilized enzyme column reactor and serum magnesium. This application is for the clinical analysis of NADPH and NADH. The reactor for NADPH and NADH contains immobilized L-glutamate dehydrogenase and L-glutamate oxidase, and that for serum magnesium immobilized hexokinase, glucose-6-phosphate dehydrogenase, L-glutamate dehydrogenase and L-glutamate oxidase. When the sample is introduced into the four-enzyme bioreactor, hydrogen peroxide is produced in proportion to the concentration of serum magnesium by the successive reactions. A co-immobilized hexokinase/glucose-6-phosphate dehydrogenase/glutamate dehydrogenase column reactor gave better efficiency compared with an enzyme column which was prepared by packing co-immobilized hexokinase/glucose-6-phosphate dehydrogenase and immobilized glutamate dehydrogenase to make two layers. Magnesium in serum was determined with 1μ L of the sample without carry-over and for an assay time of approximately 15 s. The present method is sensitive (detection limit 0.1 nmol) because Mg2+ is recycled in a column, and gives perfect linearity of the data up to 3.0 mmol/L with satisfactory precision, reproducibility, and accurate reaction recoveries.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bmc.1130040310
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  • 9
    Electronic Resource
    Electronic Resource
    An electron spin resonance study of poly(α-ethynylnaphthalene) polymerized with [Rh(norbornadiene)Cl]2 and WCl6 as catalysts (1995)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 196 (1995), S. 2969-2977 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly(α-ethynylnaphthalene)s (PENAPs) obtained with the Rh complex [Rh(norbornadiene)Cl]2 as a stereoregular polymerization catalyst of monosubstituted acetylene monomers and WCl6 were studied by using the electron spin resonance (ESR) method to inspect the geometrical structure with respect to the C=C bond in the main chain where π-radicals called solitons may be stabilized in the conjugated polymer chain. In PENAP obtained as the immobile unpaired electrons were found to be stabilized in the polymer chain, indicating a short and restricted conjugated chain, i. e., formation of a cis-transoid polymer. In PENAP obtained with WCl6 as catalyst more mobile unpaired electrons were found to be stabilized in the conjugated polymer chain not only at room temperature but also at lower temperature, indicating the presence of a π-conjugated main chain, i. e. of a trans-transoid polymer. Moreover it was found, interstingly, that the clearly resolved ESR spectrum with the hyperfine structure (solitin) could be observed at higher temperature, i. e., ca. 300°C.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1995.021960920
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  • 10
    Electronic Resource
    Electronic Resource
    A chemiluminometric method for the determination of urea in serum using a three-enzyme bioreactor (1988)
    New York : Wiley-Blackwell
    Journal of Bioluminescence and Chemiluminescence 2 (1988), S. 63-67 
    Details
    ISSN: 0884-3996
    Keywords: Urea ; chemiluminometry ; flow injection analysis ; bioreactor ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: A flow injection chemiluminometric assay for urea has been developed based on a minicolumn bioreactor packed with immobilized enzyme-bearing glass beads. The reactor contains immobilized urease, L-glutamate dehydrogenase and L-glutamate oxidase, aligned in this order (upstream to the downstream). When the sample is introduced into the bioreactor, urea is first hydrolysed by urease to produce ammonia, which is then converted into L-glutamate by L-glutamate dehydrogenase. L-Glutamate is finally oxidized by L-glutamate oxidase to produce hydrogen peroxide, which is quantified by measuring chemiluminescence emitted upon admixing with luminol and potassium ferricyanide. One assay cycle is completed within 1 minute. The method is sensitive (detection limit 0.5 nmol) and is linear in the range 0-30 mmol/l. It can be readily applied to the determination of urea in human serum, and requires no blank corrections for ammonia and/or L-glutamate present in serum samples.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bio.1170020202
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