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51.
Summary A high-performance liquid gel-permeation chromatographic method is described for the determination of human serum immunoglobulin G (IgG) by separating the fluorescent immuno complex from the free fluorescence-labeled antibody. Fluorescence-labeled antibody used in this study was fluorescein isothiocyanate (FITC)-labeled Fab fragment goat anti-human IgG (anti-IgG Fab). Immuno complexes and antibody of different molecular sizes can be separated. FITC-labeled anti-IgG Fab was added to the serum and the mixture is passed through the column. An immuno complex separates as well-delineated peak in the column void volume, and was measured by the fluorescence of the column eluate (Ex=490nm, Em=520nm). The total analysis time for a serum sample was approximately 15min. The minimum detection limit was 25 mg/dl. The relative standard deviation was below 2% (peak area). The results of the HPL-GPC analysis correlate well with those obtained by laser nephelometric assay (r=0.992). 相似文献
52.
Duncan?P.?FaggEmail author Vladislav?V.?Kharton Jorge?R.?Frade 《Journal of Solid State Electrochemistry》2004,8(9):618-625
Small (2 mol%) cobalt oxide additions to ceria-gadolinia (CGO) materials considerably improve sinterability, making it possible to obtain ceramics with 95–99% density and sub-micrometre grain sizes at 1,170–1,370 K. The addition of Co causes a significant shift of the electrolytic domain to lower pO2. This modification to the minor electronic conductivity of the electrolyte material has influence on the cathodic oxygen reduction reaction. The impedance technique is shown to provide information not only about polarisation resistance, but also about the active electrode area from analysis of the current constriction resistance. It is demonstrated that this current constriction resistance can be related to the minor electronic contributions to total conductivity in these materials. A simple imbedded grid approach gives control of the contact area allowing the properties of the electrolyte materials to be studied. A much lower polarisation resistance for the Co-containing CGO electrolyte is observed, which can be clearly attributed to an increased three-phase reaction area in the Co-containing material, as a consequence of elevated p-type conductivity. 相似文献
53.
Woo-Jin Lee Su-Il Pyun Tae-Hyun Yang Joong-Do Kim Young-Ho Baek Han-Gyu Kim 《Journal of Solid State Electrochemistry》1997,1(2):120-125
Hydrogen transport through a Pd-Ni alloy electrodeposited on a Pd substrate (Pd-Ni/Pd bilayer symmetric electrode) has been
investigated using cyclic voltammetry and a.c. impedance spectroscopy combined with the electrochemical hydrogen permeation
method. The permeation build-up current transients and the measured impedance spectra were analyzed using the time-lag method
for the bilayer electrode and a complex non-linear least squares data-fitting method based upon the derived Faradaic admittance
for the hydrogen absorption into and diffusion through the bilayer electrode under the permeable boundary condition, respectively.
The value of the hydrogen diffusivity in the Pd-Ni layer was lower than that in the Pd layer. Furthermore, the values of the
charge transfer resistance and equilibrium absorption constant for the Pd-Ni/Pd bilayer electrode were higher than those for
the Pd single layer electrode. From the experimental results, the role of the thin Ni(OH)2 film formed on the Pd-Ni layer surface in the hydrogen transport through the Pd-Ni/Pd bilayer electrode is discussed in terms
of its passivating effect and extremely large hydrogen solubility.
Received: 22 January 1997 / Accepted: 15 April 1997 相似文献
54.
Clovis Peppe Paola de Azevedo Mello Rafael Pavão das Chagas 《Journal of organometallic chemistry》2006,691(11):2335-2339
The organoindium compound derived from indium monobromide and dibromoacetonitrile reacts with carbonyl compounds to afford the corresponding 2-bromo-2-cyano-indium(III) alkoxide. The action of a second equivalent of indium monobromide onto the alkoxides derived from aldehydes promotes the Boord elimination of the β-related oxygen and bromine atoms leading to 2-alkenenitriles. 相似文献
55.
硫酸介质中Ti/SnO2/PbO2析氧阳极的研究 总被引:13,自引:0,他引:13
由于硫酸溶液具有高的电导、一般条件下性质稳定、价格相对低廉等优点,所以电化学合成大多在硫酸溶液中进行.阳极析氧是电化学合成不可避免的阳极过程.但因硫酸的强腐蚀性,以及从阳极析出的氧的强氧化性,使得能满足工业生产的阳极材料很缺乏.自1950年荷兰Hen... 相似文献
56.
A method for determining the oxygen content of the high-temperature superconductor YBa2Cu3O6.5+x is described. The superconductor is dissolved in 4.4 M hydrobromic acid, forming bromine. The mixture is then diluted with hydrochloric acid to obtain a solution of bromine and Cu(II) in 0.44 M hydrobromic acid and 1.1 M hydrochloric acid. As(III) is added in slight excess of that required to react with the bromine and the unreacted As(III) is determined by titration with potassium bromate. Oxygen does not interfere. The results of this method are in agreement with those of other iodimetric procedures. The dissolution of the superconductor in 4.4 M hydrobromic acid is much faster than in hydrochloric acid, the medium used in one iodimetric technique. YBa2Cu3O6.5+x sintered fibers and powder samples weighing from ca. 0.5 to 200 mg were analyzed for oxygen content. 相似文献
57.
<正> 光敏氧化效率是由敏化剂分子吸收光量子数及其产生单重态氧的量子产率决定的,这要求敏化剂的吸收光谱同光源的发射光谱很好地匹配。本文报道竹红菌甲素匹配高压钠灯有效地产生单重态氧,高效光敏氧化一系列具有不同反应活性的底物,成为单重态氧化学中一个新的光敏氧化体系。 相似文献
58.
Kiyoharu Tadanaga Kazuki Iwashita Tsutomu Minami Noboru Tohge 《Journal of Sol-Gel Science and Technology》1996,6(1):107-111
Nylon-6 substrates were coated with SiO2 thin films by the sol-gel method and their water permeability coefficient was evaluated. Methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS) were used as starting materials. The addition of MTES to TEOS has enabled the formation of crack-free thin films on the substrates. The thin films strongly adhered to the substrates. The water permeability coefficients of nylon-6 substrates coated with these thin films decreased with the increase in the ratio of TEOS to the total alkoxides. The pretreatment of the nylon-6 substrates with -aminopropyltriethoxysilane was found to be effective to suppress the water permeability. The water permeability was suppressed by about 40% under the optimal condition. 相似文献
59.
Jihong Cheng 《Journal of solid state chemistry》2004,177(1):126-133
LaGaO3 perovskites doped with Sr or Ba at the La site and Mg at the Ga site were prepared by solid-state reaction or sol-gel method and characterized. Enthalpies of formation from constituent oxides at 298 K were determined by high-temperature oxide melt solution calorimetry. Energetic trends are discussed in terms of defect chemistry. As oxygen deficiency increases, formation enthalpies define three trends, LaGa1−yMgyO3−δ (LGM), La1−xSrxGa1−yMgyO3−δ (LSGM), and La1−xBaxGa1−yMgyO3−δ (LBGM). They become less exothermic with increasing doping, suggesting a dominant destabilization effect from oxygen vacancies. The endothermic enthalpy of vacancy formation is 275±37, 166±18 and 138±12 kJ/mol of VO·· for LGM, LBGM and LSGM, respectively. Tolerance factor and ion size mismatch also affect enthalpies. In terms of energetics, Sr is the best dopant for the La site and Mg for the Ga site, supporting earlier studies, including oxygen ion conductivity and computer modeling. 相似文献
60.
Alexander I. Titkov Alexey N. Salanov Segrey V. Koscheev Andrey I. Boronin 《Reaction Kinetics and Catalysis Letters》2005,86(2):371-379
Summary The interaction of O2with Pd(110) has been studied by TDS and XPS at T = 400 K and at pressures PO2 from 2.6x10-6to 10 Pa. At low exposures in O2(e£1-5 L), an adsorption layer withqof ca.0.5 and with the O1s peak at BE = 529.3 eV has been found to form on the surface. Whenegrows from 5 to 108L, the position and intensity of the oxygen O1s peak remain practically constant. At the same time, as much as 5 mL of oxygen
is absorbed according to the TDS data. The results obtained by TDS and XPS indicate that oxygen penetrates deep into the subsurface
layers of palladium (315-20 ?) and is distributed in its bulk in a low concentration. 相似文献