Sealing and opening

Commercially available containers for use with parenteral products include single-dose ampuls that are heat sealed and opened by snapping at the point of least diameter, vials for multidose use, and botdes and pHable bags that are used for large volumes such as needed in intravenous infusions. Container size can vary from 1 mL to 1 L. Generally volumes up to 100 mL are available as ampuls or vials. 

Reaction of K3Co(CN) with PMMA. A 1.0 g sample of PMMA and 1.0g of the cobalt compound were combined in a standard vessel and pyrolyzed for 2 hrs at 375°C. The tube was removed from the oven and the contents of the tube were observed to be solid (PMMA is liquid at this temperature). The tube was reattached to the vacuum line via the break-seal and opened. Gases were determined by pressure-volume-temperature measurements on the vacuum line and identified by infrared spectroscopy. Recovered were 0.22g of methyl methacrylate and 0.11 g of CO and C02. The tube was then removed from the vacuum line and acetone was added. Filtration gave two fractions, 1.27g of acetone insoluble material and 0.30g of acetone soluble (some soluble material is always lost in the recovery process). The acetone insoluble fraction was then slurried with water, 0.11 g of material was insoluble in water. Infrared analysis of this insoluble material show both C-H and C-0 vibrations and are classified as char based upon infrared spectroscopy. Reactions were also performed at lower temperature, even at 260°C some char is evident in the insoluble fraction. 

Substrates should be kept clean, preferably sealed and opened just prior to use. Gloves should be worn to prevented xmwanted fingerprints and other forms of contamination from hands. If possible, the printing operation... 

J.H. Fuhrhop, U. Liman, H.H. David, Sealing and Opening Porous Monolayer Vesicle Membranes , Angew. Chem. Int. Ed., 24,339 (1985)... 

A Convenient Method for Sealing and Opening NMR Tubes Under Air-Free Conditions... 

Figure 9.31. Microreflectance of sealed- and open-tube samples of CuS04-SH20 heating rate of) 0°C min 1 wavelength of incident light, 450 nm 80 x magnification (78).

The evolution ofliquid water in the deaquation of CuSCV5H20 is illustrated by the microreflectance of powdered CuS04-5H20 in sealed and open glass capillary tubes, as shown in Figure 9.31. In an open capillary tube, the sample reflectance of the samples decreased as the temperature was increased. However, since the liquid water was confined to the capillary tube, the reflectance did not increase again on further heating. 

Sealing NMR tubes has been made easier by the introduction of commercially available sealing adaptors, which allow one to tip off standard NMR tubes without the need of additional sealing to ground-glass or O-ring joints. Commercially available NMR tubes that ate constricted on one end to allow for rapid and symmetrical flame sealing are also available, and a device to conveniently seal and open NMR tubes under air-free conditions has been described elsewhere. " ... 

So you crack the seal and open one bottle of water and put nine tablets of NaCl in it and screw the cap back on you do the same with another bottle. (As you are shaking the bottles to dissolve the NaCl tablets you make a little mental note to contact the NaCl supplier and notify them that 1 Gm means one gigameter, that is, a billion of meters while the symbol for gram is g.) The next minute you walk out of your tent and hand the paramedic two bottles of freshly prepared saline isotonic solution mission accomplished. 

An ionisation detector works on the principle that ions are absorbed by smoke particles, thus when smoke enters a chamber which contains an ionised gas some of the ions are absorbed by the smoke particles and the current flow in the chamber is reduced. In practice a radiation source is used to maintain a pre-determined level of ionisation in both a sealed and open chamber. Both chambers will therefore pass the same current. When smoke enters the open chamber the ionisation is reduced and less current flows in... 

Bulk Volume. A term used relative to the density and volume of a porous solid, e.g. a refractory brick. It is defined as the volume of the solid material plus the volume of the sealed and open pores present. 

Confined spaces include chambers, tanks (sealed and open-top), vessels, furnaces, ducts, sewers, manholes, pits, flues, excavations, boilers, reactors and ovens. 

The following containment system impairments are analysed in turn loss of air coolers, loss of dousing, open ventilation dampers, deflated airlock door seals and open airlock doors. In Canada, where four multi-unit stations have vacuum containment, a number of additional containment impairments are considered partial or total loss of vacuum failure of the instrumented containment pressure relief valves to open or close and failure of one bank of self-actuating containment pressure relief valves. These failure combinations will not, however, be discussed in detail in this report since no stations outside Canada have this type of containment. 

Both sealed and open nickel-eadmium batteries are based on similar chemical reactions. The sealed type is designed to be maintenance free and under normal conditions will not release gas, whereas an open battery has been designed to release gases when... 

The yield of iso-propylbenzene is influenced considerably by the quality of the anhydrous aluminium chloride employed. It Is recommended that a good grade of technical material be purchase in small bottles containing not more than 100 g. each undue exposure to the atmosphere, which results in some hydrolysis, is thus avoided. Sealed bottles containing the reagent sometimes have a high internal pressure they should be wrapped in a dry cloth and opened with care. 

Bromo-3-iodo-l-(4-methylphenylsulfonyl)indole (0.476 g, 1.00 mmol), methyl acrylate (0.108 g, 1.25 mmol), EtjN (0.127 g, 1.25 mmol) and Pd(OAc)2 (11 mg, 0.050 mmol) were mixed in a tube, purged with argon and the tube was sealed and heated to 100°C for 1 h. After cooling, it was opened and mixed with CH2CI2 (50 ml). The solution was washed with water and dried (Na SOJ. The residue was purified by chromatography on silica using 1 3 benzene-hexane for elution. The yield was 0.350 g (81%). 

Probably the largest compound vessels built were two triple-wall vessels, each having a bore diameter of 782 mm and a length of 3048 mm designed for a pressure of 207 MPa (30,000 psi). These vessels were used by Union Carbide Co. for isostatic compaction unfortunately the first failed at the root of the internal thread of the outer component which was required to withstand the end load (40). A disadvantage of compound shrinkage is that, unless the vessel is sealed under open-end conditions, the end load on the closures has to be resisted by one of the components, which means that the axial stress in that component is high. 

The stainless steel plates are separated (ca 3 pm between) by nonabsorbent vulcanized gaskets. Various profiles and configurations, including raised knobs, crescents, channels, or diamonds, provide a rapid, uniform heat-transfer plate surface. During operation the plates must be pressed together to provide a seal, and mounted and coimected in such a manner that air is eliminated and that the product drains from the plates without opening. 

Fractionally distd, then 35mL was sealed with about 7g KOH pellets in a borosilicate glass ampoule and heated at 135° for 48h. The ampoule was cooled and opened, and the liquid was resealed with fresh KOH in another ampoule and heated as before. This process was continued until no further decomposition was observed. The substance was then washed with distilled water, dried (CaS04) and distd. [Grafslein Anal Chem 26 523 1954.]... 

Another concept that has become quite popular in industry is the balanced mechanical seal. Most manufacturers offer seal models incorporating the balance feature. This balance is not a dynamic balance, but instead a relationship between the forces tending to open the faces in a mechanical seal and the forces tending to close the seal faces (Figure 13-8). 

If ah systems are go, turn on the seal gas. Open the expander and eompressor ease drains to purge systems. Close drains and eheek seal gas pressure. Seal gas temperature must be 70-80°F downstream of the regulator. 

When winterizing is required, the steam tracing and insulation should include the first 7.5 m of the flare stack above the vapor inlet and also in the case of a drum seal, the vapor line from the seal drum to the flare. Where steam injection to one of the smokeless tips, as shown in Figures 11 B and C is used, then the steam ring should remain outside the top of the flare tip (i.e., not internal). Where severe ambient conditions are encountered then it is recommended that the entire seal drum and flare be insulated in addition to steam tracing and open steam injection at base of flare. 

A hollow-fiber reverse-osmosis module consists of a shell which houses the hollow fibers (Fig. 11.3). The fibers are grouped together in a bundle with one end sealed and the other open to the atmosphere. The open ends of the fibers are potted into Ml epoxy sealing head plate after which the permeate is collected. The pressurized feed solution (denoted by the shell side fluid) flows radially from a central porous tubular distributor. As the feed solution flows around the outer side of the fibers toward the shell perimeter, the permeate solution penetrates through the fiber wall into the bore side by virtue of reverse osmosis. The permeate is collected at the open ends of the fibers. The reject solution is collected at the porous wall of the shell. 

A) Preparation of 1-Methyl-2-Picolinium Chloride 98 ml of cx-picoline is dissolved in 200 ml of methanol, cooled and 85 ml (at -68°C) of methyl chloride is added. The solution is charged to an autoclave, sealed and the nitrogen pressure of 300 psig is established. The mixture is heated at 120° to 130°C for 2 hours, cooled and opened. The resulting solution is then evaporated to dryness in vacuo, yielding a residue of 110 g. This residue is then dissolved in 50 ml of water and extracted with two 50 ml portions of ether. The aqueous phase is then diluted to 150 ml with water and an assay for ionic chloride is performed which indicates the presence of chloride ion equivalent to 721 mg/ml of 1-methyl-2-picolinium chloride. 

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