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61.
H. Heller H. Clever G. T. Piercy E. K. Plant M. C. Rogers S. Zweig A. Taub J. D. White F. W. Rose Jr. und K. S. Nitsche 《Fresenius' Journal of Analytical Chemistry》1943,125(1-2):66-68
Ohne Zusammenfassung 相似文献
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Bontempo D Heredia KL Fish BA Maynard HD 《Journal of the American Chemical Society》2004,126(47):15372-15373
In this communication we report a strategy for the synthesis of semitelechelic polymers reactive to cysteines. An initiator modified with a pyridyl disulfide was prepared and used for the CuBr/2,2'-bipyridine-mediated atom transfer radical polymerization (ATRP) of 2-hydroxyethyl methacrylate. Polydispersity indices (M(w)/M(n)) of the polymers with different molecular weights were 1.25 or less. The pyridyl disulfide end group was preserved during the polymerization and allowed direct conjugation of the polymer to cysteine residues of bovine serum albumin. The described method provides a general way for the preparation of protein-polymer conjugates through a reversible disulfide bond without the need for postsynthesis modification of the polymers. 相似文献
63.
Zusammenfassung Der Einfluß der Seitenwände auf das Einsetzen von Naturkonvektion in einem beheizten Fluid wird untersucht, wobei die Wärme sowohl über die Berandung als auch durch innere Wärmequellen dem Medium zugeführt wird. Betrachtet wird eine Fluidschicht, die inx-Richtung unendlich ausgedehnt und durch vier Seiten begrenzt ist.Eine zweidimensionale Approximation dieses dreidimensionalen Problems wird mit Lösungen verglichen, die sich unter Benutzung einer allgemeinen dreidimensionalen Darstellung eines toroidalen und poloidalen Vektorfeldes für den Fall von freien bzw. festen horizontalen und festen vertikalen Rändern ergeben.Für Höhen- zu BreitenverhältnisseA, die zwischen 0.001 und 100 liegen, unterscheiden sich die kritischen Rayleighzahlen bei der zweidimensionalen Approximation nur wenig von den Ergebnissen des allgemeinen dreidimensionalen Falles. Zusätzlich werden für die zweidimensionale Approximation unter Berücksichtigung innerer Wärmequellen die kritischen externen Rayleighzahlen bestimmt, wobei die Rayleighzahlen für interne Wärmequellen in einem Bereich von 0R1<106 liegen. Soweit ein Vergleich der hier gewonnenen Ergebnisse mit denen aus Experimenten und früheren theoretischen Untersuchungen möglich ist, wurde gute Übereinstimmung festgestellt.
Summary The influence of sidewalls on the onset of convection in a differentially and internally heated fluid layer is investigated. A two-dimensional approximation to the three-dimensional problem is compared to solutions using a general three-dimensional representation of the toroidal and poloidal vector fields in the case of free and rigid upper and lower boundaries with rigid sidewalls. For all aspect ratios, 0.001A100, it is found that the critical Rayleigh numbers in the two-dimensional approximation do not differ substantially from the general three-dimensional results. Additionally, in the two-dimensional approximation, the problem is investigated with both internal heating and an imposed temperature difference between the upper and lower boundaries. In this case all boundaries are rigid and the critical Rayleigh numbers, RE, are obtained for aspect ratios between 0.001 and 100 and internal Rayleigh numbers in the range 0RI<106. Where comparison of the results with experimental and previous theoretical results is possible, good agreement is found.相似文献
64.
Debora?S.?F.?Gay Yoshitaka?Gushikem Celso?C.?Moro Tania?M.?H.?Costa Edilson?V.?BenvenuttiEmail author 《Journal of Sol-Gel Science and Technology》2005,34(2):189-195
1,4-phenylenediamine-1-propylsilica hybrid xerogels were obtained for two composition at different temperatures of gelation, from 5 up to 70C. The morphological effects produced by the different gelation temperatures were investigated by using N2 adsorption-desorption isotherms and scanning electron microscopy. The thermal stability of the organic groups and their distribution on the xerogel matrix, i.e. the fraction of the organic groups that were trapped in closed pores, formed during the xerogel synthesis, and the fraction of organic groups present on the surface, were obtained by using infrared thermal analysis. The higher porosity of the xerogels and the higher thermal stability of the organic groups were achieved for samples gelled at 25C. 相似文献
65.
Mariana Alarcón-Correa Debora Walker Tian Qiu Peer Fischer 《The European physical journal. Special topics》2016,225(11-12):2241-2254
This minireview discusses whether catalytically active macromolecules and abiotic nanocolloids, that are smaller than motile bacteria, can self-propel. Kinematic reversibility at low Reynolds number demands that self-propelling colloids must break symmetry. Methods that permit the synthesis and fabrication of Janus nanocolloids are therefore briefly surveyed, as well as means that permit the analysis of the nanocolloids’ motion. Finally, recent work is reviewed which shows that nanoagents are small enough to penetrate the complex inhomogeneous polymeric network of biological fluids and gels, which exhibit diverse rheological behaviors. 相似文献
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Sofia Trakhtenberg Ramya Kumar Jason Bianchini Savin Thor Debora M. Martino 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1311-1315
Photocrosslinking of thymine‐based water‐soluble polymer films was investigated at varying preparation conditions. Adding salt or decreasing the pH of the solution from which the films were cast resulted in the decreased efficiency of photoimmobilization, while increasing the pH was found to increase the photoimmobilization efficiency. A mechanistic rationale for the observed effects is proposed. 相似文献
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Back Cover: Amino Acid Oxidation: A Combined Study of Cysteine Oxo Forms by IRMPD Spectroscopy and Simulations (Chem. Eur. J. 48/2016) 下载免费PDF全文