Glass septum

Polymer Synthesis and Modification. The condensation reaction between either BTDA or BDSDA and ODA was performed in DMAc at room temperature under a nitrogen atmosphere. ODA (0.004 mole) was added to a nitrogen-purged glass septum bottle with 7 ml DMAc. One of the dianhydrides (0.004 mole) was then added to the diamine solution with an additional milliliter of DMAc resulting in 15-25 wt% solids depending upon the monomer combination. The resulting solution was stirred for 20-24 hours to form the poly(amide acid), a polyimide precursor. For the modified polyimides, anhydrous cobalt(II) chloride (0.001 mole) was added as a solid within one-half hour after the dianhydride. 

Thermostated glass tubular reactor with fritted glass septum... 

A mixture of cyclohexanecarboxaldehyde (0.120 mL, 1.0 mmol, 1 equiv.), tin powder (0.178 g, 1.5 mmol, 1.5 equiv.) and crotyl bromide (0.125 mL, 1.2 mmol, 1.2 equiv.) in dichloromethane (0.385 mL, 6 equiv.) and water (0.108 mL, 6 equiv.) was stirred in a 10-mL round-bottomed flask equipped with a glass septum at room temperature for 48 hours. 50-mL water was added and the reaction mixture extracted with 50 mL portions of ethyl acetate. The combined organic layer was washed with 50 mL brine and 50 mL water and dried over anhydrous magnesium sulfate. The mixture was then filtered and the solvent removed in vacuo. The crude product was purified by column chromatography to afford a 78% (131 mg) yield mixture of (95%) and (5%) homoallylic alcohols (Entry 13, Table 8.1) as a colorless oil. 

Solids by solvents. The various forms of Soxhlet apparatus illus trated in Section 11,44 can be purchased with ground glass joints. A simplified form, in which the fragile side tubes are absent, is shown in Fig. II, 58, 1. The material to be extracted, if of granular form, may rest upon a sintered glass disc or upon a removable septum ... 

The checkers used a home-made, glass-jacketed funnel sealed with a rubber septum. The submitters cut one side and part of the bottom of a styrofoam cup and with tape held this in place around the lower part of the addition funnel. 

Via the Z-enolate an oven dried Schlenk tube equipped with a rubber septum is flushed with argon and charged with 0.66 mL (1.0 mmol) of butyllithium (1.5 N in hexane). The Schlenk tube is cooled to 0°C (icc/salt) and 0.12 g (1.1 mmol) of diisopropylaminc are added slowly by a syringe. This mixture is stirred for 15 min and the rubber septum is replaced by a glass stopper. The hexane and the excess diisopropyl-amine are removed under reduced pressure. After the flask is filled with argon the stopper is replaced with a septum and 0.47 g (4.3 mmol) of HMPA and 2.5 mL of THF are added. This solution is immediately cooled to — 78 °C and 0.14 g (1.1 mmol) of tert-butyl propanoate arc added quickly by syringe. After stirring for... 

A dry, 250-ml., three-necked, round-bottomed flask is equipped with a sealed mechanical stirrer (Note 5), a glass stopper, and a rubber septum through which are inserted hypodermic needles with which to evacuate the flask and to admit nitrogen. After the apparatus has been... 

B. (E)-4-(2-Phenylethenyl)benzonitrile (2). An oven-dried, 250-mL, three-necked, round-bottomed flask equipped with an argon inlet adapter, rubber septum, glass stopper, and a teflon-coated magnetic stir bar is cooled to room temperature under a flow of argon. The flask is charged successively with bis (tri-tert-butylphosphinc)palladium [(Pd(P(t-Bu)3)2] (0.238 g, 0.466 mmol, 1.5 mol% Pd) (Notes 1, 2), tris(dibenzylideneacetone)dipalladium(0) (Pd2(dba)3) (0.213 g, 0.233 mmol, 1.5 mol% Pd) (Note 3), and... 

FIGURE 6.9 Horizontal chamber for fully online HPTLC by Nyiredy 1 — evaporator, 2 — diode-array detector, 3 — quartz glass cover plate, 4 — septum, 5 — injector block, 6 — mobile phase, 7 — filter paper, 8 — Teflon chamber, 9 — chromatoplate. (Modified from Nyiredy, Sz., J. Planar Chromatogr. 15, 454-457, 2002.)... 

Glass screw-cap autosampler vial, 2-mL, with Teflon-lined septum Fisons MD-800 gas chromatograph/mass spectrometer or equivalent MassLynx Software, Version 2... 

Vials autosampler, clear glass with Teflon-lined septum caps, 1.8-mL sample storage, clear glass with Teflon-lined caps, 12-mL... 

Prom the experimental point of view the static headspace sampling technique is very simple. The sample, either solid or liquid, is placed in a glass vial of appropriate size and closed with a Teflon-lined silicone septum. The 1 is carefully... 

Fig. 6.10 Methods of preparation of bilayer lipid membranes. (A) A Teflon septum with a window of approximately 1mm2 area divides the solution into two compartments (a). A drop of a lipid-hexane solution is placed on the window (b). By capillary forces the lipid layer is thinned and a bilayer (black in appearance) is formed (c) (P. Mueller, D. O. Rudin, H. Ti Tien and W. D. Wescot). (B) The septum with a window is being immersed into the solution with a lipid monolayer on its surface (a). After immersion of the whole window a bilayer lipid membrane is formed (b) (M. Montal and P. Mueller). (C) A drop of lipid-hexane solution is placed at the orifice of a glass capillary (a). By slight sucking a bubble-formed BLM is shaped (b) (U. Wilmsen, C. Methfessel, W. Hanke and G. Boheim)...

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