Glass concentrations

C cerium concentrate glass polishing, glass decolorizing dominant element... 

A simpler and more convenient form of Beckmann apparatus, requiring much less solvent and giving equally accurate results, is shown in Fig. 33. It consists of a boiling-tube furnished with two side pieces, one of which is stoppered and serves to introduce the substance and the other acts as a condenser. The boiling-tube stands on an asbestos pad and is surrounded by two short concentric glass cylinders surmounted by a mica plate. The other parts of the apparatus are similar to those in the older form and the process is conducted in the same way. 

Fig. 2.8.6 (a) (i) I implementation of vertical cylindrical Couette cell using concentric glass tubes (ii) velocity image taken across a horizontal slice and (iii) velocity profile taken across the cell. Note that the marker fluid in the inner cylinder exhibits rigid body motion... 

The electrode consists of two concentric glass tubes, the inner one of which contains mercury in contact with a paste of mercury, mercury(I) chloride (calomel), and potassium chloride. This is in contact with a solution of potassium chloride in the outer tube which itself makes contact with the sample solution via a porous frit, fibre or ground-glass sleeve (Figure 6.1). 

A Dufton column was not available to the checkers. In its place a 2.5-cm. x 38-cm. column packed with glass helices was used. This column was heated by a 4.5-cm. concentric glass jacket wrapped with Nichrome ribbon. A 6.5-cm. concentric... 

The saturated calomel reference electrode is an example of a constant-potential electrode. A drawing and a photograph of a typical SCE available commercially are shown in Figure 14.4. It consists of two concentric glasses or tubes, each isolated from the other except for a small opening for electrical contact. 

A further study by the Olesik group [138] used an interface with a laminar flow in the direction of the detector. The interface was a stainless-steel tee with the capillary threaded through the colinear ends of the tee. A sheath electrolyte was delivered through the lower arm of the tee with a peristaltic pump. Both a high efficiency nebuliser (HEN) and a concentric glass nebuliser were used in the study the former was used with a conical spray chamber and the latter with a Scott double-pass spray chamber. Increasing the sheath electrolyte flow-rate enabled the laminar flow to be eliminated, therefore improv-... 

One-liter bottles are desirable to allow for repeated measurements and preconcentration (in the case of low tritium concentrations). Glass bottles are preferred, as tritium can diffuse through PVC bottles and equilibrate with the air. 

Pneumatic Concentric Nebuliser. The current design of the pneumatic concentric nebuliser is probably the most common type used. It consists of a concentric glass through which a capillary tube is fitted. The sample is drawn up from the spray... 

Figure 2.10 Designs of (a) concentric glass nebuliser (Meinhard type) available showing enlarged fine bore tip to suit clear solutions and wide bore tip to suit solutions containing high salt content (b) PTFE nebuliser suitable for HF acids with fittings. (Reproduced with kind permission from E-POND S.A., C.P. 389, CH-1800 Vevey, Switzerland)...

Sample Introduction Samples can be introduced into the ICP by argon flowing at about 1 L/min through the central quartz tube. The sample can be an aerosol, a thermally generated vapor, or a fine powder. The most common means of sample introduction is the concentric glass nebulizer shown in Figure 28-9. The sample is transported to the tip by the Bernoulli effect. This transport process is called aspiration. The high-velocity gas breaks up the liquid into fine droplets of various sizes, which are then carried into the plasma. 

Fig. 40. Pneumatic nebulizers for plasma spectrometry. A concentric glass nebulizer, B cross-flow nebulizer, C Babington nebulizer, D fritted-disk nebulizer. (Reprinted with permission from Ref. [95].)...

A type of concentric glass nebulizer which is operated at pressures of several tens of bars is known as a high efficiency nebulizer (HEN) [110]. More recently micro-... 

Fig. 49. Particle size distributions of pneumatic nebulizers for ICP. MAK, high-pressure cross-flow nebulizer CGN, concentric glass nebulizer JAB, Jarrell—Ash Babington nebulizer JAC, Jarrell—.Ash fixed cross-flow nebulizer (Reprinted with permission from Ref. [139].)...

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