Needle valve adapter

Two graduated dropping funnels of 500-ml. capacity equipped with pressure-equalizing tubes and small diameter tips to allow two solutions to be added in fine streams were used. They were also equipped with screw-in type plungers with Teflon fluorocarbon tips to allow fine adjustment of the flow rates. The checkers utilized standard 500-ml. dropping funnels and two needle valve adapters shown in Figure 1. 

In a dry-box operation, a 3-ounce Fischer-Porter aerosol compatibility tube is loaded with approximately 10 g. of cesium fluoride and then equipped with a stainless-steel needle-valve adapter and a 323A Hoke valve, f After removal from the dry-box, Swagelokf connections are made from the valve to a metal standard-taper joint and the whole assembly attached to... 

Fig. 1 Sources and description of apparatus. (I) Pittsburgh Valve and Fitting Company A, Nupro safety relief valve (100 psi release) 3-6R-4M-100 B, Cajon i in. Tee B-4-T C, Cajon i in. Hex long nipple B-4-HLN(2-l in.) D, Cajon 1 in. Cross B-4-CS E, Whitey Ball Valve B-43M-S4 F, Whitey 1 in. Forged Body Valve B-1VM4-S4 G, Cajon hex reducing nipple, 1 to 4 in. B-4-HRN-2. (II) Mattheson Gas Products H, Standard Guage (2-3% accuracy) 0-100 psig 63-3112. (Ill) Lab Crest Scientific I, Needle Valve adapter 110-957 Rubber washer 110-973 J, Aerosol reaction vessel, 3 oz 110-023-0(X)3.

The less volatile residues should be quite free of bromosilane. However, as a precaution, nitrogen is admitted into the reaction tube, the adapter is removed, and the contents of the tube are poured over pulverized Dry Ice contained in a sink in a hood. Water is then allowed to run over the Dry Ice. The recovered hydrogen bromide can be stored at room temperature after first being condensed at —196° into a 150-ml. stainless-steel cylinder fitted with a stainless-steel needle valve. It is important to... 

The smallest bellows seal valve that has been adapted to sodium service is a i-inch needle valve used in drawing off small quantities of sodium into the oxide sample operation. This valve has operated at temperatures up to 500 °C. 

The actuation chamber is made from stainless steel. It houses the canister within its adapter sleeve during dosing. A smooth surface provides a face seal between canister valve stem tip and sample injection passage. The close tolerance between the external wall of the adapter and the internal wall of the actuation chamber induces a partial vacuum which creates a controlled pumping action causing sample methanol to flush the injection passage after each dose. A replaceable 16 gauge needle fits onto a standard luer tapered tip. 

The hydrogen generator flask A is a similarly shaped Erlenmeyer flask. The inlet adapter to which this flask is attached incorporates a mercury valve D which controls the rate at which the sodium borohydride solution contained in the 250 ml burette G is allowed to flow into the flask A via the syringe needle H (gauge 17 or 19) and the vent holes F in the control valve D. 

The SPME hyphenation to HPLC is even simpler. The external loop of a classic injection valve is replaced by a T-adapter, aUowing insertion of the SPME needle and pushing out the fiber (Fig. 6). For desorption of the analytes, the valve is moved to the INJECT position. The return to the... 

LOAD position of the valve isolates, again, the T-adapter and allows retraction of the fiber and withdrawal of the SPME needle. Special attention should be given to the compatibihty of the fiber with the mobile phase, to eliminate risks associated with fiber material swelling. 

The Teflon seal joint (Fisher Scientific catalog number 14-513-100) consists a Teflon bearing with an exterior 24/40 taper, an 0-ring, and an adapter chuck. The sq>tumed side neck carries a needle-stemmed spoon that can be lowered into the reactor solution to unload the catalyst it carries. The other side neck is connected through a three-way valve to a gas tank and a constant-pressure manometric unit. The gas tank supplies the gaseous reactant while the manometric unit provides a convenient and sensitive method for monitoring the synthesis reaction by means of the gas uptake. The manometric unit (4-6) consists of two mobile arms of equal-diameter burets attached to an adjustable pulley system that is actuated by two... 

A cylinder of the helium to be analyzed is connected to the inlet of the apparatus through a special adapter valve attached to the cylinder. This is a "needle-nose" valve and is much better for regulatingflow than the cylinder valves. This... 

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