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71.
Müller-Späth T Ströhlein G Aumann L Kornmann H Valax P Delegrange L Charbaut E Baer G Lamproye A Jöhnck M Schulte M Morbidelli M 《Journal of chromatography. A》2011,1218(31):5195-5204
The cation-exchange capture step of a monoclonal antibody (mAb) purification process using single column batch and multicolumn continuous chromatography (MCSGP) was modeled with a lumped kinetic model. Model parameters were experimentally determined under analytical and preparative conditions: porosities, retention factors and mass transfer parameters of purified mAb were obtained through a systematic procedure based on retention time measurements. The saturation capacity was determined through peak fitting assuming a Langmuir-type adsorption isotherm. The model was validated using linear batch gradient elutions. In addition, the model was used to simulate the start-up, cyclic steady state and shut down behavior of the continuous capture process (MCSGP) and to predict performance parameters. The obtained results were validated by comparison with suitable experiments using an industrial cell culture supernatant. Although the model was not capable of delivering quantitative information of the product purity, it proved high accuracy in the prediction of product concentrations and yield with an error of less than 6%, making it a very useful tool in process development. 相似文献
72.
Shimon D Hovav Y Feintuch A Goldfarb D Vega S 《Physical chemistry chemical physics : PCCP》2012,14(16):5729-5743
Proton Dynamic Nuclear Polarization (DNP) experiments were conducted on a 3.4 T homebuilt hybrid pulsed-EPR-NMR spectrometer, on static samples containing 10 mM or 40 mM TEMPOL in frozen glassy solutions of DMSO/water. During DNP experiments proton-NMR signals are enhanced with the help of microwave (MW) irradiation on or close to the Electron Paramagnetic Resonance (EPR) spectrum of the free radicals in the sample, transferring polarization from the free electrons to the nuclei. In the solid state a distinction is made between three DNP enhancement mechanisms: the Solid Effect (SE), the Cross Effect (CE) and Thermal Mixing (TM). In an effort to determine the dominant DNP mechanisms responsible for the enhancement of the nuclear signals, electron and nuclear spin-lattice relaxation rates, enhancement buildup times and microwave (MW) swept DNP spectra were measured as a function of temperature and MW irradiation strength. We observed lineshape variations of the DNP spectra that indicated changes in the relative contributions of SE-DNP and CE-DNP with temperature and MW power. Using a theoretical model describing the SE-DNP and CE-DNP the DNP spectra could be analyzed without involving the TM-DNP mechanism and the relative SE-DNP and CE-DNP contributions to the nuclear enhancement could be determined. From this analysis it follows that lowering the temperature beyond 20 K increases the SE-DNP and decreases the CE-DNP contributions. Possible explanations for this behavior are suggested. 相似文献
73.
Suppose that X is an h-homogeneous zero-dimensional compact Hausdorff space, i.e., X is a Stone dual of a homogeneous Boolean algebra. Using the dual Ramsey theorem and a detailed combinatorial analysis of what we call stable collections of subsets of a finite set, we obtain a complete list of the minimal sub-systems of the compact dynamical system (Exp(Exp(X)), Homeo(X)), where Exp(X) denotes the hyperspace comprising the closed subsets of X equipped with the Vietoris topology. The importance of this dynamical system stems from Uspenskij’s characterization of the universal ambit of G = Homeo(X). The results apply to the Cantor set, the generalized Cantor sets X = {0,1} κ for noncountable cardinals κ, and to several other spaces. A particular interesting case is X = ω* = βω \ ω, where βω denotes the Stone- ?ech compactification of the natural numbers. This space, called the corona or the remainder of ω, has been extensively studied in the fields of set theory and topology. 相似文献
74.
Amihood Amir Yonatan Aumann Gad M. Landau Moshe Lewenstein Noa Lewenstein 《Journal of Algorithms in Cognition, Informatics and Logic》2000,37(2):247
Let a text string T of n symbols and a pattern string P of m symbols from alphabet Σ be given. A swapped version T′ of T is a length n string derived from T by a series of local swaps (i.e., t′ℓ ← tℓ + 1 and t′ℓ + 1 ← tℓ), where each element can participate in no more than one swap. The pattern matching with swaps problem is that of finding all locations i for which there exists a swapped version T′ of T with an exact matching of P in location i of T′. It has been an open problem whether swapped matching can be done in less than O(nm) time. In this paper we show the first algorithm that solves the pattern matching with swaps problem in time o(nm). We present an algorithm whose time complexity is O(nm1/3 log m log σ) for a general alphabet Σ, where σ = min(m,Σ). 相似文献
75.
76.
77.
H. Seliger G. Aumann V. Genrich H. -H. Görtz M. Holupirek T. Knäble E. Rössner H. Schütz und M. Philipp 《Colloid and polymer science》1978,256(1):102
Ohne Zusammenfassung 相似文献
78.
Günter Aumann 《Journal of Geometry》1981,16(1):41-49
We extend striction and, parameter of distribution to (k+1)-dimensional generalized ruled surfaces with edge ruled surfaces. 相似文献
79.
H. Seliger E. Rössner G. Aumann V. Genrich M. Holupirek T. Knäble und M. Philipp 《Colloid and polymer science》1977,255(11):1143
Ohne Zusammenfassung 相似文献
80.
Summary Using column switching techniques a rapid and precise HPLC method for the determination of pentoxifylline was developed. Shorter
precolumns with RP 2 filling material and longer purging times at neutral pH reduce the amount of interfering peaks while
retaining a 100% extraction yield. Of all stationary phases of the analytical column tested only Nucleosil Phenyl yielded
base line separation and acceptable life time of the column.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献