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931.
932.
We analyze here the force noise associated with the mechanical damping of a test body surrounded by a large volume of rarefied gas, considering the statistics of momentum exchange in inelastic molecular collisions. In addition to calculating the force noise on a cube, sphere, and cylinder, we discuss the limits in applying this analysis to experimental configurations in which the test body is surrounded by an enclosure that is only slightly larger than the test body itself. 相似文献
933.
M. R. Weber 《Mathematische Nachrichten》2009,282(10):1478-1487
In Banach spaces ordered by a normal cone that contains interior points the positive invertibility of operators is studied. If there exists a uniformly positive functional then any positively invertible operator A possesses a B -decomposition, i.e., a positive decomposition A = U – V with the properties: U–1 exists, VU–1 ≥ 0, Ax ≥ 0, U x ≥ 0 imply x ≥ 0 and r (VU–1) < 1. Earlier it was shown that the existence of a B -decomposition with r (VU–1) < 1 is sufficient for the positive invertibility of the operator A. Peris' result is obtained as a special case of the main theorem. The decomposition is demonstrated for a positively invertible operator in a Banach space ordered by an ice cream cone (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
934.
Mario Gómez José Quincoces Klaus Peseke Manfred Michalik Helmut Reinke 《Journal of carbohydrate chemistry》2013,32(7):851-865
ABSTRACT 1,6-Anhydro-2-(dicyanomethylene)-2,3-dideoxy-4-S-ethyl-4-thio-β-D-erythro-hexopyranose (1) reacted with tosyl azide or sulfur and triethylamine to furnish the 5-aza-10, 11-dioxatricyclo[6.2.1.02,6]undeca-2(6),3-diene-3-carbonitrile 2 and the 10,11-dioxa-5-thiatricyclo[6.2.1.02,6]undeca-2(6),3-diene-3-carbonitrile 3, respectively. The reactions of 1 with arylisothiocyanates furnished the 11,12-dioxa-5-thiatricyclo[7.2.1.02,7]dodeca-2(7),3-diene-3-carbonitriles 4 and 5. 3 underwent cyclization with triethyl orthoformate and ammonia or hydrazine hydrate to afford the 5,7-diaza-14,15-dioxa-9-thiatetracyclo[10.2.1.02,10.03.8]pentadecatetra(tri)enes 7 and 8, respectively. 相似文献
935.
Muthiah Manoharan Akin Akinc Rajendra K. Pandey June Qin Philipp Hadwiger Matthias John Kathy Mills Klaus Charisse Martin A. Maier Lubomir Nechev Emily M. Greene Pradeep S. Pallan Eriks Rozners Kallanthottathil G. Rajeev Martin Egli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2011,123(10):2332-2336
936.
Characterization and functionalization of cellulose microbeads for extracorporeal blood purification
Marion Ettenauer Fritz Loth Katrin Thümmler Steffen Fischer Viktoria Weber Dieter Falkenhagen 《Cellulose (London, England)》2011,18(5):1257-1263
In the frame of this work, cellulose microbeads with an average particle size of 2.3 μm were characterized with respect to
porosity using a batch solute exclusion method and two groups of model substances, namely proteins and polystyrene sulfonates.
The pores of the microbeads were almost completely accessible to proteins with Stokes radii below 2.5 nm. More than 60% of
the pores were accessible to albumin, which is relevant for the application in blood purification, since many target substances
are albumin bound. Activation of the microbeads with increasing amounts of sodium metaperiodate yielded matrices with dialdehyde
contents between 100 and 1,000 μmol/g. The activated beads were well suited for the covalent attachment of functional ligands,
such as antibodies. Immobilization of antibodies against the pro-inflammatory cytokine TNF-α resulted in efficient TNF-α adsorbents
which possess application potential in extracorporeal blood purification, e.g. for the modulation of cytokine levels as supportive
therapy for sepsis and other inflammatory disorders. 相似文献
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