Controlled Atmosphere Valve (CAV)

A linear valve system for performing controlled atmosphere experiments by NMR. The concentric valve mechanism consists of a sturdy, precision machined TFE plug with a Viton o-ring seal. A glass vacuum adapter is supplied with each system. It is secured to the top of the valve with a press fit sealed by an o-ring. Before ordering a CAV or PCAV please read this instruction notice.

Application Note:

To use the CAV, the glass adapter is first secured to the vacuum line. With the valve attached and in the open position, vacuum transfers can be made to and from the sample tube. Once the proper sample environment is attained, the valve can be closed and the system can be removed from the vacuum line. The process is repeated to retrieve the sample.

This system is very useful in the study of organometallics or other moisture and air sensitive samples. Note: It is not recommended to use ketones, aldehydes, ethers or aliphatic esters with Viton rubber. Aegis o-rings are available for use with these compound types (see below) and must be ordered separately. Note: To the catalog number, add the length “L” (XXX), in mm, that places the valve directly on top of the spinner. This is necessary to maintain good spinning quality. Example: NE-CAV5-170 indicates L=170mm.

References: Constrained Geometry Chromium Catalysts for Olefin Polymerization; Y. Liang, G.P.A. Yap, A.L. Rheingold, K.H. Theopold, Organometallics 1996, 15, 5284 [(Ph)2 nacnac]MCl2(THF)2 (M=Ti, V, Cr)-- A New Class of Homogeneous Olefin Polymerization Catalysts Featuring β-Diiminate Ligands, W.K. Kim, M.J. Fevola, L.M. Liable-Sands, A.L. Rheingold, K.H. Theopold Organometallics 1998, 17, 4541

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Adapter with 24/40 outer joint, glass,  Specialty NMR Sample Tubes,
Controlled Atmosphere Valve (CAV) Sample Tube, Spare Parts



Nut and Ferrule, Specialty NMR Sample Tubes, Controlled Atmosphere Valve (CAV) Sample Tube, Pressure Valve (PCAV) Sample Tube, CAV / PCAV Spare Parts
Nut and Ferrule set for 1/16” tubing, one each