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101.
Pyruvate oxidase (E.C. 1.2.3.3.) is immobilized by adsorption on a wet PVC membrane. Glutamate-pyruvate transaminase activity (5–1600 IU l?1) in serum is determined by a pyruvate oxidase sensor consisting of the immobilized pyruvate oxidase coupled to a platinum electrode for measuring hydrogen peroxide, after an l-alanine—α-ketoglutarate reaction. The assay requires ?60 s, and has a precision of 2–3%. Endogenous pyruvate should not interfere if measurements are made > 30 s after starting the reaction. 相似文献
102.
Frans C. Mijlhoff Gerrit H. Renes Kunio Kohata Kazuko Oyanagi Kozo Kuchitsu 《Journal of Molecular Structure》1977,39(2):241-252
The structure of 1,1-difluoroethylene was determined, from gas phase electron diffraction data obtained independently in Leiden and Tokyo and the rotational constants of F2CCH2, F2CCHD and F2CCD2 derived from the microwave study by Chauffoureaux. The two electron diffraction data agreed without significant discrepancy. From a joint least squares analysis of the diffraction and microwave data, the following rg bond distances and rz bond angles were derived: CC = 1.340 ± 0.006 Å, C-F = 1.315 ± 0.003 Å, C-H = 1.091 ± 0.010 Å, ∠C-C-F = 124.7 ± 0.3°, ∠C-C-H = 119.0 ± 0.4°, where the uncertainties represent estimated limits of error. 相似文献
103.
Werner Paschinger Kunio Yubuta Yuta Saiga Toshiro Takabatake Gerald Giester Peter Rogl 《ChemInform》2016,47(29):no-no
Single crystals of Ce3Pt4Sn6 (I) and Ce1‐xPt6Al13+2x (x = 0.207, (II)) are isolated by mechanical fragmentation of specimens grown from self‐fluxes (Sn or Al, resp.) by slow cooling from the melt. 相似文献
104.
105.
Performance of the apparatus was evaluated in terms of stationary phase retention, partition efficiency and sample loading capacity. Preliminary studies with short coils revealed high retention of the stationary phase under a proper combination of the head-tail elution and planetary motion. Preparative capability of the apparatus was successfully demonstrated on efficient multigram separations of 2,4-dinitrophenyl amino acids, indole auxins, and bacitracin in a pair of large multilayer coils with a total capacity of 1.5 l. 相似文献
106.
Sakai K Umezawa S Tamura M Takamatsu Y Tsuchiya K Torigoe K Ohkubo T Yoshimura T Esumi K Sakai H Abe M 《Journal of colloid and interface science》2008,318(2):440-448
The adsorption and micellization behavior of novel sugar-based gemini surfactants (N,N(')-dialkyl-N,N(')-digluconamide ethylenediamine, Glu(n)-2-Glu(n), where n is the hydrocarbon chain length of 8, 10 and 12) has been studied on the basis of static/dynamic surface tension, fluorescence, dynamic light scattering (DLS) and cryogenic transmission electron microscope (cryo-TEM) data. The static surface tension of the aqueous Glu(n)-2-Glu(n) solutions measured at the critical micelle concentration (cmc) is observed to be significantly lower than that of the corresponding monomeric surfactants. This suggests that the gemini surfactants, newly synthesized in the current study, are able to form a closely packed monolayer film at the air/aqueous solution interface. The greater ability in the molecular association is supported by the remarkably (approximately 100-200 times) lower cmc of the gemini surfactants compared with the corresponding monomeric ones. With a combination of the fluorescence and DLS data, a structural transformation of the Glu(n)-2-Glu(n) micelles is suggested to occur with an increase in the concentration. The cryo-TEM measurements clearly confirm the formation of worm-like micelles of Glu(12)-2-Glu(12) at the concentration well above the cmc. 相似文献
107.
Toshinobu Kanai Hiroki Ishibashi. Yoshikazu Hayashi Kunio Oka Takaaki Dohmaru Tatsuo Ogawa Shoji Furukawa Robert West 《Journal of Polymer Science.Polymer Physics》2001,39(11):1085-1092
The thermochromic behavior of poly(di‐n‐octylsilane) {[Si(C8H17)2]n; PDOS} was studied by ultraviolet (UV) absorption, differential scanning calorimetry, and X‐ray diffraction measurements. The structure of PDOS in the low‐temperature phase strongly depended on not only the temperature but also the rate of cooling, that is, the thermal history. Temperature‐dependent UV absorption spectra were highly dependent on thermal hysteresis. Cooled rapidly (10 K/min), PDOS showed two absorption peaks at 3.32 and 3.51 eV in low‐temperature‐ordered phases, whereas a single absorption peak at 3.32 eV became predominant with slow cooling (0.3 K/min). The appearance of the two peaks at low temperatures suggested that a mixture of different conformations was introduced by rapid cooling. A fiber diffraction pattern measured at 240 K after rapid cooling also showed evidence of the existence of novel conformation. A temperature‐dependent powder X‐ray diffraction pattern changed significantly between 270 and 280 K. Rapid cooling reduced the intensity of the X‐ray diffraction peak in this temperature region. This intensity change was explained by the conformational mixture in the polymer. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1085–1092, 2001 相似文献
108.
A 5-amino-8-hydroxyquinoline (AHQ)-modified gold nanoparticle (GNP) layer was fabricated on an inner wall of a silica capillary column by alternatively passing a citrate-stabilized GNP solution and an AHQ solution in a repeating fashion. The observations by a field emission scanning electron microscope showed that the thickness of the resulting GNP layer was about 0.15 microm. This column was then used as an open tubular solid-phase extraction column for cadmium, followed by electrothermal atomic absorption spectrometric determination. The detection limit of 0.009 ng ml(-1) was obtained. 相似文献
109.
In the article, we study the structure of Galois coverings of self-injective artin algebras with infinite cyclic Galois groups. In particular, we characterize all basic, connected, self-injective artin algebras having Galois coverings by the repetitive algebras of basic connected artin algebras and with the Galois groups generated by positive automorphisms of the repetitive algebras. 相似文献
110.
An effective vector exchange in a quark model, previously used for nucleon-antinucleon annihilation and meson decays, is applied to nucleon-meson and decuplet baryon-meson couplings. A reasonable fit to experimental data is obtained.This article is written in honour and memory of Michael Moravcsik. He was both a dedicated physicist and a very humane person with wide interests in the world around him. One of us (EMH) knew him well and will continue to cherish his friendship 相似文献