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51.
An improved high-performance liquid chromatographic method for the determination of chlormethiazole levels in plasma is described. The drug is extracted from plasma using commercially available reversed-phase extraction columns; recovery values obtained using Sep-Pak C18 and Bond Elut C1, C2, C4, C6, C8, C18 columns are compared. Separation was achieved by reversed-phase chromatography, using a mobile phase consisting of 0.025 M sodium acetate buffer, pH 4.5-acetonitrile (67:33) at a flow-rate of 1.6 ml/min in conjunction with a 15-cm Jones Chromatography Apex ODS column. The analytical column was protected by a Waters Assoc. Guard-Pak module containing a Guard-Pak CN insert. Using ultraviolet detection at 254 nm chlormethiazole levels in the region of 50 ng/ml can be measured with only 500 microliter of plasma. 相似文献
52.
53.
Susumu Arimori James H. Hartley Michael L. Bell Chan S. Oh Tony D. James 《Tetrahedron letters》2000,41(52):10291-10294
A diethanolamine pendant polystyrene polymer was prepared by the copolymerization of diethanolaminomethyl styrene, styrene, and divinylbenzene. The composition of the polymer resins produced agreed with copolymerization starting ratios. The polymer resins readily immobilized phenylboronic acid in THF and released pure phenylboronic acid quantitatively in THF/water/acetic acid. 相似文献
54.
55.
56.
Kohlrausch Holborn M. Wien Siemens Halske Washburn Bell Schlesinger Curtis W. A. Taylor S. F. Acree Western Electric Company Leeds Northrup E. W. Washburn Parker H. Pfleiderer H. von Ubisch Wetham Hartley Barrett Pfeiffer C. A. Nowak L. Archbutt und R. Höber 《Fresenius' Journal of Analytical Chemistry》1918,57(6-7):314-326
Ohne Zusammenfassung 相似文献
57.
A. Leclère A. Hahn A. Kretschmann C. Du Rietz S. Hähnel Dr. N. Gerbers Co. m. b. H F. Tödt L. S. Foster I. J. Gruntfest M. Déribéré L. J. Desha R. E. Sherrill L. M. Harrison G. Kloz H. Leonhardt N. Bjerrum G. S. Hartley W. B. Fortuno M. G. Mellon I. M. Kolthoff L. S. Guss H. Eichler H. Gorke E. Köppe F. Staiger A. Thiel F. W. Panepinto M. Kilpatrick T. Teorell E. Stenhagen W. L. German 《Analytical and bioanalytical chemistry》1939,116(9-10):336-347
58.
Nadia Kapernaum C. Scott Hartley Dr. Jeffrey C. Roberts Dr. Florian Schoerg Daniel Krueerke Dr. Robert P. Lemieux Prof. Dr. Frank Giesselmann Prof. Dr. 《Chemphyschem》2010,11(10):2099-2107
The phase diagrams of four binary mixtures of chemically similar smectogenic mesogens differing only in molecular length are investigated. In these bidisperse systems the length ratio varies systematically. The phase diagrams show the stabilization of the smectic A and the destabilization of the smectic C phase with increasing length ratio as a general trend. Detailed small‐angle X‐ray diffraction and electro‐optic measurements revealed a decrease in smectic translational order and a continuous reduction of the tilt angle with increasing length difference. These surprising results are of general interest for the understanding of the structure and dynamics of smectic phases. The remarkably strong impact of the length difference on the smectic layer structure and the phase behavior is discussed from a mechanistic point of view taking into account sterical interactions. For the observed structural changes in these bidisperse smectics we propose pronounced out‐of‐layer fluctuations with increasing length difference as driving force, causing neighboring molecules within nearest layer into a smectic A‐like packing. 相似文献
59.
Michael I. Hartley 《Periodica Mathematica Hungarica》2006,53(1-2):149-156
Summary This article announces the creation of an atlas of small regular
abstract polytopes. The atlas contains information about all regular abstract
polytopes whose automorphism group has order 2000 or less, except those of
order <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"3"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>512k$
where $k\geq1$. The article explains also the techniques used to
create the atlas, and gives some summary tables. At the time of printing, the
url for the atlas is http://<a href = "http://www.abstract-polytopes.com/atlas">www.abstract-polytopes.com/atlas</a>. 相似文献
60.
Michael I. Hartley 《Discrete Mathematics》2010,310(12):1835-1844
We present the results of an investigation into the representations of Archimedean polyhedra (those polyhedra containing only one type of vertex figure) as quotients of regular abstract polytopes. Two methods of generating these presentations are discussed, one of which may be applied in a general setting, and another which makes use of a regular polytope with the same automorphism group as the desired quotient. Representations of the 14 sporadic Archimedean polyhedra (including the pseudorhombicuboctahedron) as quotients of regular abstract polyhedra are obtained, and summarised in a table. The information is used to characterize which of these polyhedra have acoptic Petrie schemes (that is, have well-defined Petrie duals). 相似文献