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61.
Nikolay Vassilev Almudena Medina Bettina Eichler-Löbermann Elena Flor-Peregrín Maria Vassileva 《Applied biochemistry and biotechnology》2012,168(5):1311-1318
Cells of Aspergillus terreus, free and immobilized in polyurethane foam, were employed in itaconic acid fermentation processes on glycerol-based media. The purpose was to assess their suitability for animal bone char solubilization and the development of a biotechnological alternative to P fertilizers chemically produced from rock phosphate. Animal bones constitute a renewable source of P that can replace the traditionally used finite, nonrenewable rock phosphate as a P source. Glycerol was an excellent substrate for growth (10.2 g biomass L?1) and itaconic acid production (26.9 g?L?1) by free fungal cells after 120-h fermentation. Simultaneously, A. terreus solubilized the insoluble phosphate to a yield of 23 to 50 %, depending on the particle size and concentration. Polyurethane foam cut into cubes of 0.5–0.6 cm per side, with 0.3 mm pore size and applied at 2.0 g?L?1 proved to be an excellent cell carrier. In repeated batch fermentation, the immobilized mycelium showed a high capacity to solubilize animal bone char, which resulted on average in 168.8 mg?L–1 soluble phosphate per 48-h cycle and 59.4 % yield (percent of total phosphate) registered in the fourth batch. 相似文献
62.
Zusammenfassung Auf Grund einer von uns durchgeführten Untersuchung über die Zustandsdiagramme der Silberchalkogenidsysteme Ag2Te-Ag2Se, Ag2Te-Ag2S, Ag2Se-Ag2S und über die Diagonalquerschnitte Ag2Se0.5Te0.5-Ag2S, Ag2S0.5Te0.5-Ag2Se, Ag2Se0.5S0.5-Ag2Te wurden ein Projektion des Raumdiagramms der Liquidusflachen und einige der wichtigsten isothermen Schnitte des dreidimensionalen Systems Ag2Te-Ag2Se-Ag2S aufgestellt. Nach der Interpretation der Art und Lage der einzelnen Phasen wurden für jedes der Systeme die elektrischen und wärmephysikalischen Eigenschaften bei Temperaturen von der des flüssigen Stickstoffes bis zu den Temperatures des Phasenübergangs untersucht und der thermoelektrische Wirkungsgrad (Z, K–1) berechnet.
On the basis of a previous investigation on the phase diagrams of the silverchalcogenide systems Ag2Te-Ag2Se, Ag2Te-Ag2S and Ag2Se-Ag2S and the diagonal sections Ag2Se0.5Te0.5-Ag2S, Ag2S0.5Te0.5-Ag2Se and Ag2Se0.5S0.5-Ag2Te, the projections of liquidus surfaces and more characteristic isothermal sections of the Ag2Te-Ag2Se-Ag2S phase diagram were constructed. After interpretation of the types and situations of the separate phases in each of the systems studied, their electric and thermophysical properties were investigated in the temperature range from 77 K up to the temperatures of the phase transitions and the values of thermoelectric efficiency were calculated,Z, Ksu–1.
Ag2Te-Ag2Se, Ag2Te-Ag2S, Ag2Se-Ag2S Ag2Se0.50.5-Ag2S, Ag2S0.5Te0.5-Ag2Se, Ag2Se0.5S0.5-Ag2Te Ag2Te-Ag2Se-Ag2S. . 77 . .相似文献
63.
Phosphonylmethylaminocyclopentane‐1‐carboxylic acid was synthesized using Kabachnik–Fields reaction conditions in high yield and was characterized by NMR (1H, 31P, and 13C) and FAB spectroscopy. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:229–230, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10124 相似文献
64.
C. Risacher V. Belitsky V. Vassilev I. Lapkin A. Pavolotsky 《International Journal of Infrared and Millimeter Waves》2005,26(6):867-879
We present the results of the development of a 275–370 GHz, fixed-tuned double sideband (DSB) receiver based on superconductor-insulator-superconductor (SIS) junction mixer. The mixer block uses a full height rectangular waveguide and employs a novel radial-like probe structure with integrated bias-T. The measured uncorrected receiver noise temperature is 30–50 K corresponding to about 2–3 quantum noise across the full frequency band with an IF from 3.8 to 7.6 GHz. The mixer is to be used on the Atacama Pathfinder EXperiment (APEX) submillimeter telescope in Chile. 相似文献
65.
66.
A tensor invariant is defined on a quaternionic contact manifold in terms of the curvature and torsion of the Biquard connection involving derivatives up to third order of the contact form. This tensor, called quaternionic contact conformal curvature, is similar to the Weyl conformal curvature in Riemannian geometry and to the Chern–Moser tensor in CR geometry. It is shown that a quaternionic contact manifold is locally quaternionic contact conformal to the standard flat quaternionic contact structure on the quaternionic Heisenberg group, or equivalently, to the standard 3-Sasakian structure on the sphere iff the quaternionic contact conformal curvature vanishes. 相似文献
67.
K. Konstantinov S. Karbanov V. Vassilev 《Zeitschrift für Physik B Condensed Matter》1990,81(2):151-154
The effect of Sb superconducting materials with nominal composition Bi1.6Pb0.4–x
Sb
x
Sr2Ca2Cu3O
y
(x=0.01–0.14) and Bi1.5Pb0.5–x
Sb
x
Sr2Ca2Cu3O
y
(x=0.025–0.12) has been investigated. These materials were subjected to DTA, ICP emission spectrometry, SEM, XRD and electric resistance measurements. It was found that the introduction of Sb raises the melting temperature of the material, it also raisesT
c
(up to 110K) at several defined stoichiometric ratios. A certain lack of correspondence between the 2223 phase volume and theT
c
value was noticed and a possible explanation has been proposed. 相似文献
68.
Helmut Duddeck Blagoy Blagoev Nikolina D. Berova Vassil Vassilev 《Magnetic resonance in chemistry : MRC》1983,21(2):122-124
Three diastereomeric bornane derivatives have been assigned configurational structures by 13C NMR measurements in the presence of Yb(dpm)3. 相似文献
69.
X‐Ray, DSC and magnetic susceptibility measurements were performed with NiBi specimens in the interval from room temperature to 700 K. The hypothesis of solid‐state transitions in this phase was not confirmed. Thermal and magnetic effects are observed, but they are due to the existence of small amount of phases others than NiBi (i.e. unreacted Ni and Bi). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
70.
G. P. Vassilev 《Crystal Research and Technology》1991,26(3):345-347
The correlation between the short range parameters and some thermodynamic properties has been examined for 44 binary alloys. Qualitative agreements have been obtained in the majority of the systems. Some previsions have been made for the controversially cases. 相似文献