Tubes open both ends

To eliminate part of the edge problem in the sliding plates, we can slide a cylinder inside a tube. If both ends are open and the gap is... 

Flattened tubes Anode-supported or cathode-supported tubes are flattened so that there is no need to seal the side of the tubes. When both ends are open, at least the entrances are sealed. When one end is closed, there is a need for an additional pipe to introduce air or fuel. Normally, interconnect materials are fabricated simultaneously. For this purpose, oxide interconnects are more appropriate. Figure 2.10 shows the flattened tube cells fabricated by Kyocera to be operated at 750°C. 

The heating of the vessels is accomplished by means of a small bath or a micro-Bunsen burner. The vessel can be clamped at such a distance from the burner that the contained liquid boils gently under reflux. Smooth boiling is ensured by the addition of 1-2 minute pieces of unglazed porcelain, or of a short piece of melting-point tubing open at both ends. 

This bizarre-looking worm lives in a U-shaped parchment-like tube up to 25 cm long (Fig. 7.1.1), which is usually buried in sand or mud, exposing only the openings of both ends. It is a filter feeder, and very widely distributed, sometimes forming dense colonies on the seabed. In fact, this species propagated so densely in the Los Angeles Flarbor around 1965, Dr. Rimmon Fay was able to collect 10,000... 

Fig. 7.1.1 Left Two parchment-like tubes inhabited by Chaetopterus variopedatus. The tubes are usually buried in muddy sand, exposing only the openings at both ends. Center The worms after removal of the casings. Right Diagram showing luminous area (after Panceri, 1878) the third pair from the top corresponds to the 12th segment.

A gas-inducing agitator system is an alternative to a multistirrer system. It contains a hollow shaft with orifices above the liquid level and a hollow impeller. A typical hollow impeller consists of a tube that is, at the centre, connected to the hollow shaft. Both ends of the impeller are cut at 45 so that, at rotation, the open portions of the tube are at the near side of the stirrer. There are several modifications of this design. Obviously, there is a minimum impeller speed at which the onset of gas induction occurs. Loop reactors are also successfully used. 

Sometimes you may get a supply of tubes that are open on both ends You don t just use these as is. Light a burner, and close off one end, before you start. Otherwise your sample will fall out of the tube (see Closing Off Melting Point Tubes, following). 

If you have melting point tubes that are open at both ends and you try to take a melting point with one, it should come as no surprise when your compound falls out of the tube. You ll have to close off one end, to keep your sample from falling out (Fig. 32). So light a burner and get a stiff small blue flame. SLOWLY touch the end of the tube to the side of the flame, and hold it there. You should get a yellow sodium flame, and the tube will close up. There is no need to rotate the tube. And remember, touch— just touch—the edge of the flame, and hold the tube there. Don t feel you have to push the tube way into the flame. 

When an explosive gas mixture is placed in a tube having one or both ends open, a combustion wave can propagate when the tube is ignited at an open end. This wave attains a steady velocity and does not accelerate to a detonation wave. 

It is not an oversimplification to describe the gastrointestinal (GI) tract as one very long tube open at both ends, the mouth and the anus. The major pieces of the tube are the mouth, throat, esophagus, stomach, small intestine and large intestine, or colon, and the rectum and anus. Most of the length is due to the intestines, which are actually highly coiled. 

Ultrafiltration hollow-fiber modules are usually made with a shell and tube configuration. The fibers are potted at both ends of the module with the fiber lumen open for recirculation of the process stream (Figure 21). Naturally, strainers or prefilters must be utilized to eliminate plugging of the fibers. At Nude-pore, it has been shown that larger diameter hollow fibers, 1.5 to 3mm in i.d., are much less prone to fouling. Fortunately, all UF hollow fiber systems can be back-washed and are amenable to a number of cleaning techniques. 

Briggs (B12) was able to subject water at room temperature to a negative pressure of nearly 270 atm. The experimental technique consisted of spinning a horizontal glass tube ( scrupulous cleanliness is necessary ) about a vertical axis located at its center. The tubing contained the liquid and was open at both ends. The centrifugal force needed to break the liquid column was observed. The experimental results are shown in Fig. 24. 

PIPETTE. A slender glass tube open at both ends and having an expanded area at or near the center designed to contain a specific volume of liquid, e.g., 5 ml. Liquid is drawn into the tube by oral or, for the sake of safety, some other form of suction. 

The original bazooka consisted of a one-piece, elec battery-operated weapon, of the open(at both ends) tube type which fired a rocket with a shaped charge warhesd. The launcher was provided with sights and shoulder frame. The improved launcher was made in two pieces, weighed l61bs... 

Claessen s Detonator. A detonator consisting of a tube open at both ends to allow the chge to be ignited at both ends instead of at one end only, so that two waves of deton will meet at about the midpoint of the tube, thus causing more effective deton of the main chge in which the detonator tube is inserted... 

The combustion may be carried out in two ways (a) in a tube sealed at one end, the C02 being generated from materials inside the tube, and (6) in a tube open at both ends, the C02 being generated in a second vessel or in a Kipp s apparatus of the Pregl type and passed into the combustion tube. Method (a) is the more convenient when estimations are conducted occasionally, and method (b) when estimations are frequently conducted. 

Insert sample Into quartz tube open from both ends wash sample with water at 50°C and Irradiate Wash hair with water and air-dry digest sample with concentrated HNO3 by... 

Figure 10.47. Structure (j) (truncated icosahedron) is well known to the chemical community as buck-minsterfullerene, C6o, comprising hexagons and pentagons. It has been well established, both chemically and geometrically, that the pentagons in the structure are necessary to effect three-dimensional closure, and without them only open, two-dimensional graphitic layers are formed. All fullerenes, and even the topical Bucky tubes (Figure 10.2), that consist of fused hexagons are open at both ends unless pentagons are incorporated into the structure.

Hollow fine fiber membranes are extremely fine polymeric tubes 50-200 micrometers in diameter. The selective layer is on the outside surface of the fibers, facing the high-pressure gas. A hollow-fiber membrane module will normally contain tens of thousands of parallel fibers potted at both ends in epoxy tube sheets. Depending on the module design, both tube sheets can be open, or as shown in Figure 8.1, one fiber end can be blocked and one open. The high-pressure feed gas flows past the membrane surface. A portion of the feed gas permeates the membrane and enters the bore of the fiber and is removed from the open end of the tube sheet. Fiber diameters are small because the fibers must support very large pressure differences feed-to-permeate (shell-to-bore). 

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