Abstract. In this paper, polymeric hollow fibers prepared from polypropylene and polybutylene terephthalate were used as CE columns. Surface modifications with polyacrylamide greatly improved the performance of the capillaries. Separations of substituted pyridines, model proteins and standard ribonucleotides were demonstrated. The column efficiency for model proteins was over 200,000 theoretical plates. Comparisons of electroosmotic flow, UV absorption properties, heat dissipation, and diameter variation between fused silica capillaries and polymeric hollow fibers were made. The practical potential of small diameter polymeric hollow fibers as CE columns was evaluated.

Abstract. Surface treatment methods were developed for bonding of a polyacrylamide layer on the inside surface of polypropylene hollow fiber columns for capillary electrophoresis. Details of different modification procedures involving surface activation and in situ polymerization, using dynamic and static coating of reagents, are described. Both linear and cross-linked polyacrylamide modified surfaces greatly improved the electrophoretic performance of the capillaries. The column efficiencies for model proteins reached as high as 370,000 theoretical plates on an 85 pm i.d. polyacrylamide surfacetreated polypropylene hollow fiber column. A variety of applications, including the separation of several very polar compounds at a pH of 10.6, were demonstrated. Reproducibility measurements were used to illustrate the performance and high pH stability of the resultant columns.

Image analysis can be a means to effectively elucidate morphological differences with both light [1,2] and electron microscopy. [3,4] These procedures have been used to evaluate morphological differences of cross sections of bundles of hair to determine gender differences [3] and morphological variations of caucasoid hair.[4] The purpose of the present investigation was to use image analysis to determine whether morphological differences could be demonstrated between head hair from Egyptian mummies from Fag el Gamous, Fayum, compared with living residents from the same region of Egypt (Mediterranean) as well as caucasoid and oriental hair.Hair samples were cleaned and processed in resin as previously described [1] which involved sonication in acetone to remove oil, and embedment in Spurr resin.[5] Sections of resin embedded hair were stained in aqueous 1% toluidine blue O, 1% azure II, and 1% sodium carbonate. Staining time varied. Mummy hair stained in less than 1 min, but freshly grown hair required up to 5 min. Images were projected using a Leitz Wezlar Prado Universal projector, equipped with a micro attachment. The projected images were recorded and numbered in an orientation so individual hairs were separated so merging of images did not occur.. For each sample, 50 randomly selected individual hair cross-sections were recorded. The images were scanned by an image analyzer. The image analyzer detected 63 shades of gray. The range between 50 and 63 was selected for analysis.Images were analyzed using ANOVA,Tukey HSD Multiple Comparison tests and Discrimination Analysis to study hair from 9 male and 15 female mummies and two mummies of unknown sex. Hair from 18 caucasoid males and 13 caucasoid females and 4 Chinese were also studied. Morphometric analyses of images were performed using a Macintosh Centris 650 frame grabber board and "Prism" image analysis software. Eighteen morphometric parameters relative to size and shape were evaluated as follows. Area (AREA) is the simple area of the feature. Convex area (CARE) is the area within a taut-string around a feature. Perimeter (PERI) is the length of the feature boundary. Convex perimeter (CPER) is the length of a taut-string around the feature. Length (LENG) is the longest cord within the feature. Breadth (BREA) is the minimum caliper diameter of the feature. Fiber length (FIBE) is the length of the feature along its medial axis. Width (WIDT) is the minor dimension of the feature. Equivalent diam (EQUI) is the diam of a circle with the same area of the feature. Inscribed radius (NSCS) is the radius of the largest circle that can be drawn in the feature. Form factor (FORM) is 4π x area/perimeter. This is 1.0 for a perfect circle and diminishes for irregular shapes.

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Attack of S‐ vs N‐Nucleophiles on 2‐Halomethylquinazoline 3‐Oxides.