Capillary outer

FIGURE I 8 At the detection window of the capillary the polyimide layer of the capillary outer coating is burned. At this spot the capillary is extremely fragile and may break easily. 

Cover material Glass Capillary outer diameter, inner diameter 375 pm, 50-150 pm... 

A compact sensor of greatly reduced dimensions (outer diameter x length 36 x 46 mm) has been constructed and is shown in Fig. 2. In order to conveniently accommodate enzyme columns and to ensure isolation from ambient temperature fluctuations, a cylindrical copper heat sink was included. An outer Delrin jacket further improved the insulation. The enzyme column (inner diameter x length 3x4 mm), constructed of Delrin, was held tightly against the inner terminals of the copper core. Short pieces of well-insulated gold capillaries (outer diameter/inner diameter 0.3/0.2 mm) were placed next to the enzyme column as temperature-sensitive elements. Microbead thermistors were mounted on the capillaries with a heat-conducting epoxy. Two types of mini system has been constructed as discussed below. 

Ratio of capillary outer to inner diameter Time interval... 

Hollow liber (outer diameter <0.5 mm) and capillary (outer diameter >0.5 nun) ceramic membranes constitute the very last development in the field of inorganic membranes. As for polymer hollow fiber m branes, a large surface/volume ratio is expected for the modules as well as the possibility of keeping uppermost properties of ceramics, that is, high mechanical, chanical, andtanperature resistance. Production of ceramic hollow fibers or capillaries with an asynunetric or homogeneous structure (Figure 9.6a) can be achieved in... 

Alginate gel (CaAlg) beads were prepared by dropping aqueous solutions of NaAlg (2.0w/v%) from a capillary (outer diameter 0.10 cm, inner diameter 0.08 cm) into CaCU solutions (0.1 mol dm " ) and were immersed in them for at least 3 days. 

Glass needles are formed from borosilicate glass capillaries (outer diameter 1.2 nun, inner diameter 0.94 mm, length 10 cm Sutter Instrument Co.) having a thin, internal filament to aid filling on a horizontal needle puller (P-87, Sutter Instrument Co.). The needles are pulled to form a 3-mm tapered, sealed tip, which will be broken under halocarbon oil. 

As is evident firom the theory of the method, h must be the height of rise above a surface for which AP is zero, that is, a flat liquid surface. In practice, then, h is measured relative to the surface of the liquid in a wide outer tube or dish, as illustrated in Fig. n-6, and it is important to realize that there may not be an appreciable capillary rise in relatively wide tubes. Thus, for water, the rise is 0.04 mm in a tube 1.6 cm in radius, although it is only 0.0009 mm in one of 2.7-cm radius. 

The apparatus consists of a tube T (Fig. 76) usually of total height about 75 cm. the upper portion of the tube has an internal diameter of about I cm., whilst the lower portion is blown out as shown into a bulb of about 100 ml. capacity. Near the top of T is the delivery-tube D of coarse-bored capillary, bent as shown. The tube T is suspended in an outer glass jacket J which contains the heating liquid this jacket is fitted around T by a split cork F which has a vertical groove cut or filed m the side to allow the subsequent expansion of the air in J. The open end of the side-arm D can be placed in a trough W containing water, end a tube C, calibrated in ml. from the top downwards, can be secured ts shown over the open end of D. 

Capillary Tubes Figure 12.42 shows a cross section of a typical capillary tube. Most capillary tubes are made from fused silica coated with a 20-35-)J,m layer of poly-imide to give it mechanical strength. The inner diameter is typically 25-75 )J,m, which is smaller than that for a capillary GC column, with an outer diameter of 200-375 )J,m. 

Three common types of nozzle are shown diagrammatically. Types A and K are similar, with sharp cutoffs on the ends of the outer and inner capillaries to maximize shear forces on the liquid issuing from the end of the inner tube. In types K and C, the inner capillary does not extend to the end of the outer tube, and there is a greater production of aerosol per unit time. These concentric-tube nebulizers operate at argon gas flows of about 1 1/min. 

Solution (Wet) Spinning. In the most widely used solution spinnerette system (60) the spinnerette consists of two concentric capillaries, the outer capillary having a diameter of approximately 400 ]Am and the central capillary having an outer diameter of approximately 200 ]lni and an inner diameter of 100 ]lni. Polymer solution is forced through the outer capillary while air or Hquid is forced through the inner one. The rate at which the core fluid is injected into the fibers relative to the flow of polymer solution governs the ultimate wall thickness of the fiber. Figure 19 shows a cross section of this type of spinnerette. 

Hollow Fiber-Capillary Hollow Fiber reFers to verv small diameter membranes. The most siiccessFiil one has an outer diameter oF onlv 93 jlrn and is used For reverse osmosis, (iapillarv membranes are larger-diarneter membranes used For liquid separations. The distinction betw een them has blurred to the point where there is a virtual... 

The following brief account is concerned with factors that affect the acces-sibihty of the OH groups of cellulose, since this is the determining factor for its dissolution, hence subsequent derivatization. Electron microscopy. X-ray scattering and porosimetry of cellulose fibers have clearly shown the presence of non-uniform pores, capillaries, voids and interstices in the fiber surface [25]. Consequently, the total surface area of cellulose fibers exceeds by far the geometrical outer surface. Pore structure determines the internal... 

The polyethersulfone capillary ultrafiltration membranes (Daicel Chemical Industries, Ltd., inner diameter 0.8 mm, outer diameter 1.3 mm, length 40 cm, molecular weight cutoff 150 000, water permeability 3 x 10 m m s kPa at 298 K) were used. The length and area of membrane consisting of seven hollow fibers are 40 cm and 70 cm. ... 

Capillary tube outer diameter 1.59 mm Flow velocities 20-200 mm s ... 

OS 33] ]R 16h] ]P 25] For the nitration of single-ring aromatics in a capillary-flow reactor, internal circulation, exhibiting an inner downwards and an outer upwards flow, in the aqueous slug of a two-phase flow was simulated [94]. 

The aqueous solution flows from the jet nozzle to a receiving capillary with no overflow into the outer stream, resulting in short contact times of around 0.05 s. Analysis is implemented by flowing the outer organic phase continually through a closed loop and monitoring concentration changes spectrophotometrically. The apparatus used by Freeman and Tavlarides employed capillaries with internal diameters of 2 mm, and the... 

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