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91.
Laurent Griffe Dr. Mary Poupot Dr. Patrice Marchand Dr. Alexandrine Maraval Dr. Cédric‐Olivier Turrin Dr. Olivier Rolland Pascal Métivier Dr. Gérard Bacquet Dr. Jean‐Jacques Fournié Dr. Anne‐Marie Caminade Dr. Rémy Poupot Dr. Jean‐Pierre Majoral Dr. 《Angewandte Chemie (International ed. in English)》2007,46(14):2334-2334
92.
S. V. Alferov L. G. Tomashevskaya O. N. Ponamoreva V. A. Bogdanovskaya A. N. Reshetilov 《Russian Journal of Electrochemistry》2006,42(4):403-404
A basic scheme of the use of the Gluconobacter oxydans bacteria cells as a biocatalyst at an anode of a biofuel cell with air-based cathode is raised up. The anode and cathode of the cell are made of graphite; 2,6-dichlorophenolindophenol serves as an electron transport mediator; and glucose is the substrate to be oxidized. The open-circuit voltage is 55 mV, for the bacteria cell, the mediator, and glucose concentrations of 3 mg/ml (raw weight), 34 mM, and 10 mM, respectively. The voltage and current of the biofuel cell loaded with an external resistance of 10 kohm are 5.6 mV and 0.56 mA. The cell’s internal resistance is 88 kohm. 相似文献
93.
Prilezhaeva I. N. Solov'ev N. P. Khramushin N. I. 《Russian Journal of Electrochemistry》2004,40(11):1223-1226
Transformation of impedance spectra into relaxation time spectra (RTS) is used for determining contributions of individual processes of the oxygen electroreduction reaction (OER) to the polarization resistance of the electrochemical cell. The transformation technique involves the solution of the convolution equation found with the aid of a modified Van Cittert iteration algorithm checked on model impedance spectra. The technique, when used to analyze impedance spectra of electrochemical cells air|Pt|YSZ|YSZ + Pt|air, shows that the conversion of a globular structure of the YSZ + Pt cermet layer to a columnar one is accompanied by a change of peak amplitudes in RTS. The revealed RTS dynamics when heated to 750°C is compared with peculiarities of individual processes in OER. 相似文献
94.
95.
基因工程技术已经成为研究和生产重组人血清白蛋白(rHSA)替代人血清白蛋白(HSA)的重点技术,而白蛋白的纯化则是该技术的关键。本文主要介绍了从转基因猪血中纯化rHSA的一种新方法,即热乙醇沉淀与多级色谱分离相结合的rHSA纯化方法。热乙醇沉淀法可从猪血浆中获得rHSA粗提取液,此时rHSA的纯度可达69.5%,回收率达51.3%。进一步采用多级色谱分离法,即阴离子交换色谱和反相色谱法进一步纯化,得到rHSA的最终纯度约为100.0%,总回收率为41.1%。该方法为从转基因猪血浆中大规模纯化用于临床和生化研究的高纯度rHSA提供可能,同时也为rHSA替代HSA奠定了基础。 相似文献
96.
Peter Brodelius Kjell Nilsson Klaus Mosbach 《Applied biochemistry and biotechnology》1981,6(4):293-307
Whole cells ofTrigonopsis variabilis were immobilized by entrapment in Ca2+-alginate and used for the production of α-keto acids from the corresponding D-amino acids. The D-amino acid oxidase within
the immobilized cells has a broad substrate specificity. Hydrogen peroxide formed in the enzymatic reaction was efficiently
hydrolyzed by manganese oxide co-immobilized with the cells. The amino acid oxidase activity was assayed with a new method
based on reversed-phase HPLC. Oxygen requirements, bead size, concentration of cells in the beads, flow rate, and other factors
were investigated in a “ trickle-bed ” reactor. 相似文献
97.
Artificial red cells with crosslinked hemoglobin membranes 总被引:1,自引:0,他引:1
Thomas A. Davis William J. Asher Herbert W. Wallace 《Applied biochemistry and biotechnology》1984,10(1-3):123-132
Artificial cells containing concentrated hemoglobin (Hb) solution were prepared by interfacial polymerization of Hb with glutaraldehyde
(GA) in liquid membrane capsules (LMC). A solution containing 30% of Hb was emulsified in mineral oil as red cell-size microdroplets,
and this emulsion was dispersed in an aqueous phase containing glutaraldehyde to form LMC. The LMC were semipermeable templates
that held the microdroplets of Hb in suspension while GA diffused through the oil to the microdroplet surfaces. The GA crosslinked
Hb at the surface of each microdroplet to form an artificial red-cell membrane encapsulating Hb solution. A water-soluble
surfactant was used to eject the cells from the LMC and suspend them in saline.
Several surfactants were evaluated. Cell size was controlled by agitation speed during preparation of the original emulsion.
Cells of 2.52 = ±1.69 μm were prepared. The encapsulated Hb retained capacity to bind and release O2. The cells had aP
50 of 8.9 torr (1200 Pa) and a capacity of 0.55 cc O2/g of total Hb, indicating that the crosslinked portion of the Hb did not contribute to O2 transport. 相似文献
98.
食物中的钼与人体健康 总被引:5,自引:0,他引:5
综述了食物中钼与人体健康之间的关系.主要包括常见食物中的钼含量,钼在人体中的代谢,钼的生物学功能以及钼对人体健康的影响等. 相似文献
99.
100.
The sorptive potential of sunflower stem (180-300 μm) for Cr(III) ions has been investigated in detail. The maximum sorption (≥85%) of Cr(III) ions (70.2 μM) has been accomplished using 30 mg of high density sunflower stem in 10 min from 0.001 M nitric and 0.0001 M hydrochloric acid solutions. The accumulation of Cr(III) ions on the sorbent follows Dubinin-Radushkevich (D-R), Freundlich and Langmuir isotherms. The isotherm yields D-R saturation capacity Xm = 1.60 ± 0.23 mmol g−1, β = −0.00654 ± 0.00017 kJ2 mol−2, mean free energy E = 8.74 ± 0.12 kJ mol−1, Freundlich sorption capacity KF = 0.24 ± 0.11 mol g−1, 1/n = 0.90 ± 0.04 and of Langmuir constant KL = 6800 ± 600 dm3 mol−1 and Cm = 120 ± 18 μmol g−1. The variation of sorption with temperature (283-323 K) gives ΔH = −23.3 ± 0.8 kJ mol−1, ΔS = −64.0 ± 2.7 J mol−1 K−1 and ΔG298k = −4.04 ± 0.09 kJ mol−1. The negative enthalpy and free energy envisage exothermic and spontaneous nature of sorption, respectively. Bisulphate, Fe(III), molybdate, citrate, Fe(II), Y(III) suppress the sorption significantly. The selectivity studies indicate that Cr(III), Eu(III) and Tb(III) ions can be separated from Tc(VII) and I(I). Sunflower stem can be used for the preconcentration and removal of Cr(III) ions from aqueous medium. This cheaper and novel sorbent has potential applications in analytical and environmental chemistry, in water decontamination, industrial waste treatment and in pollution abatement. A possible mechanism of biosorption of Cr(III) ions onto the sunflower stem has been proposed. 相似文献