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21.
Brian H. Davison Nhuan P. Nghiem Gerald L. Richardson 《Applied biochemistry and biotechnology》2004,114(1-3):653-669
More than 25 sorbents were tested for uptake of succinic acid from aqueous solutions. The best resins were then tested for
successive loading and regeneration using hotwater. The key desired properties for an ideal sorbent are high capacity, complete
stable regenerability, and specificity for the product. The best resins have a stable capacity of about 0.06 g of succinic
acid/g of resin at moderate concentrations (1–5 g/L) of succinic acid. Several sorbents were tested more exhaustively for
uptake of succinic acid and for successive loading and regeneration using hot water. One resin, XUS 40285, has a good stable
isotherm capacity, prefers succinate over glucose, and has good capacities at both acidic and neutral pH. Succinic acid was
removed from simulated media containing salts, succinic acid, acetic acid, and sugar using a packed column of sorbent resin,
XUS 40285. The fermentation byproduct, acetate, was completely separated from succinate. A simple hot water regeneration successfully
concentrated succinate from 10 g/L (inlet) to 40–110 g/L in the effluent. If successful, this would lower separation costs
by reducing the need for chemicals for the initial purification step. Despie promising initial results of good capacity (0.06
g of succinic/g of sorbent), 70% recovery using hot water, and a recovered concentration of >100 g/L, this regeneration was
not stable over 10 cycles in the column. Alternative regeneration schemes using acid and base were examined. Two (XUS 40285
and XFS-40422) showed both good stable capacities for succinic acid over 10 cycles and >95% recovery in a batch operation
using a modified extraction procedure combining acid and hot water washes. These resins showed comparable results with actual
broth. 相似文献
22.
Michal Demetrian 《International Journal of Theoretical Physics》2007,46(3):652-663
The vacuum decay in a de Sitter universe is studied for the class of effective inflaton potentials that curvature at the top
is less than as well as greater than a critical value determined previously. By comparing the actions of the Hawking - Moss
instanton and the Coleman - de Luccia instanton(s) the mode of vacuum decay is determined in this critical situation. 相似文献
23.
用Von Neumann熵研究了附加克尔介质的压缩真空场与二能级原子依赖强度耦合相互作用量子体系的量子纠缠特性.讨论了初始压缩真空场的压缩度以及克尔非线性作用的强度对该量子体系纠缠特性的影响.结果表明,克尔介质的非线性作用的强弱可以改变体系量子纠缠的周期性;在初始压缩度较大(r=5)时,克尔介质的非线性作用可导致原子与场持续地处于最大纠缠态,无消纠缠态或持续地处于消纠缠态.
关键词:
压缩真空态
克尔介质
依赖强度耦合J-C模型
Von Neumann熵
量子纠缠 相似文献
24.
We consider the problem of a self-consistent determination of an essentially inhomogeneous equilibrium state of classical plasma. The solutions of the stationary Vlasov–Poisson equations are constructed in the form of a localized transition layer that separates the domains of homogeneous plasmas with different equilibrium parameters. The layer can also transform into a local perturbation inside a homogeneous plasma. In both cases, the solution contains neither mass currents nor electric currents, and all electrodynamic and hydrodynamic quantities and their derivatives are continuous. The parameters of the adjacent domains uniquely determine the transition layer structure. 相似文献
25.
M. R. Setare 《International Journal of Theoretical Physics》2004,43(11):2237-2242
We compute particle creation for a real massive scalar field conformally coupled to a spatially closed Robertson–Walker space-time background, with time-dependent scale factor. This is a dynamical Casimir effect with moving boundaries. 相似文献
26.
Zh. D. Chaplanova Yu. K. Mikhailovskii V. E. Agabekov V. K. Ol’khovik N. A. Galinovskii E. A. Gracheva 《Journal of Applied Spectroscopy》2007,74(3):333-337
We have studied the spectral properties and morphology of thin films (TVD films) formed by thermal vacuum deposition of 4,4′-bis[(E)-1-(1,3-benzoxazol-2-yl)-2-ethenyl]-1,1′-biphenyl
and its substituted derivatives. We have shown that introducing bulky 2,2′-oxyhexyl substituents into the biphenyl units leads
to a shift of the fluorescence maximum for the TVD films toward shorter wavelengths, a decrease in their photostability, and
aggregation of the films during storage.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 3, pp. 300–303, May–June, 2007. 相似文献
27.
In this paper, we discuss the detailed optical design of a beam line that is under construction on the synchrotron radiation source, Indus-1. Toroidal mirrors are used as pre-and post- focusing elements and a toroidal grating monochromator as a dispersing element. Using three interchangeable gratings, this monochromator will give, at a moderate resolution, a good throughput on the sample in the wavelength range 40 to 1000 Å. Effect of various parameters and their optimization on the resolution and throughput characteristics have been studied by ray tracing calculations, and presented. 相似文献
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