Thimble

Due to the many problems concerning steam generators of nuclear power plants over the last decades, we developed our own inspection equipment and services. Next to this main activity, we provide inspections for nuclear power plants components such as thimbles, guide carts and baffle bolts. 

The crude organic material is placed in a porous thimble G (made of tough filter-paper), and the latter placed as shown within the inner tube C. The apparatus is then fitted below to a bolt-head flask H containing the requisite solvent, and above to a reflux water-condenser J. 

For solids of low density, the top of the porous thiinhle A should be above the siphon tube t. otherwise the solid may tend to float out of the thimble and pass down the siphon tube. 

Many continuous extractions involving solid samples are carried out with a Soxhiet extractor (Figure 7.18). The extracting solvent is placed in the lower reservoir and heated to its boiling point. Solvent in the vapor phase moves upward through the tube on the left side of the apparatus to the condenser where it condenses back to the liquid state. The solvent then passes through the sample, which is held in a porous cellulose filter thimble, collecting in the upper reservoir. When the volume of solvent in the upper reservoir reaches the upper bend of the return tube, the solvent and any extracted components are siphoned back to the lower reservoir. Over time, the concentration of the extracted component in the lower reservoir increases. 

For analysis, white phosphoms is typically extracted through a fritted thimble with refluxed toluene. Any trace amounts of water are captured in a cahbrated sidearm to the apparatus. The soflds on the frit are weighed, the water measured, and the phosphoms calculated by difference. For impure samples of phosphoms, the toluene extract may be analy2ed with a gas chromatograph (gc) equipped with a phosphoms—nitrogen detector. 

Use of Desiccants and Chemical Means to Remove Water. Another means to remove the water of esterification is calcium carbide supported in a thimble of a continuous extractor through which the condensed vapor from the esterification mixture is percolated (41) (see Carbides). A column of activated bauxite (Elorite) mounted over the reaction vessel has been used to remove the water of reaction from the vapor by adsorption (42). 

Soxhlet thimbles and filter papers may contain traces of lipid-like materials. For manipulations with highly pure materials, as in trace-pesticide analysis, thimbles and filter papers should be thoroughly extracted with hexane before use. 

Water-soluble salts are best purified by preparing a concentrated aqueous solution to which, after decolorising with charcoal and filtering, ethanol or acetone is added so that the salts crystallise. They are collected, washed with aqueous ethanol or aqueous acetone, and dried. In some cases, water-soluble salts can be recrystallised satisfactorily from alcohols. Water-insoluble salts are purified by Soxhlet extraction, first with organic solvents and then with water, to remove soluble contaminants. The purified salt is recovered from the thimble. 

Copper (I) thiophenolate [1192-40-1] M 172.7, m ca 280°, pKj 6.62 (for PhS ). The Cu salt can be extracted from a thimble (Soxhlet) with boiling MeOH. It is a green-brown powder which gives a yellow-green soln in pyridine. Wash with EtOH and dry in a vacuum. It can be ppted from a pyridine soln by addition of H2O, collect ppte, wash with EtOH and dry in a vacuum. [Synthesis 662 1974, J Am Chem Soc 79 170 1957-, Chem Ber 90 425 1957.]... 

Iron (III) meso-5,10,15,20-tetraphenylporphine chloride complex [16456-81-8] M 704.0. Crystallise by extraction from a thimble (Soxhlet) with CHCI3. Concentrate the extract to ca lOmL and add ca 80mL of hot MeOH. Dark blue crystals separate on cooling. It can be recrystallised several times from CHCl3-MeOH. Avoid prolonged heating. It is quite soluble in organic solvents but insoluble in pet ether. [J Am Chem Soc 70 1808 1948 UV 73 4315 7957.]... 

Ceramic candles, which are thimble-shaped, porous, acid-resistant ceramic tubes. Although efficiencies exceeding 98% have been reported, the candles have high maintenance requirements because they are very fragile. 

A. Silver trifluoroacetate. To a suspension of 187 g. (0.81 mole) of silver oxide (Note 1) in 200 ml. of water is added 177 g. (1.55 moles) of trifluoroacetic acid (Note 2). The resulting solution is filtered, and the filtrate is evaporated to dryness under reduced pressure. The dry silver trifluoroacetate thus obtained is purified by placing it in a Soxhlet thimble and extracting with ether, or by dissolving the salt in 1.2 1. of ether, filtering through a thin layer of activated carbon, and evaporating the filtered ether solution to dryness. The yield of colorless crystalline salt obtained after removal of the ether is 300 g. (88%). 

The HFBR at Brookhaven National Laboratory is a heavy water moderated and cooled reactor designed to provide an intense beam of neutrons to the experimental area. In addition using thimbles i oiitaincd within the vessel, it provides isotopic production, neutron activation analysis, ami muiemi irradiations. It began operation in 1965 at a power of 40 MW to be upgraded to 60 MW m 19S2. 

If the contaminated airflow rate that is to be exhausted, or the internal pressure, varies too much it could be advantageous to use an exhaust connection with a small distance between tube and duct, acting as an opening for additional air when contaminant flow rare is low. This could be in the form of a large exterior hood covering the outlet from the process and leaving only a very small opening gap for external air (thimble). See Fig. 10.40. 

Auslauge-. lixiviating, leaching, extraction, -be halter, m. lixiviating tank, -hiilse,/. extraction thimble, -hasten, m. lixiviating vat, leaching vat. 

Extraktions-anlage, /. extraction plant, -ap-parat, m. extraction apparatus, -dauer, /. time of extraction. -flUssigkeit, /. extraction liquid, liquid extract. -gef ss, n. extraction vessel, -hiilse, /. extraction shell or thimble. -kolben, m. extraction flask, -mittel, n. extracting agent, extraction solvent. -miihle,/. extraction mill, -rtickstand, m. extraction residue. 

Patrone, /. thimble, shell (for extractions) cartridge pattern stencil mandrel die collet. 

A mixture of 40.5 g (0.15 mol) of 3-carbethoxy-4-hydroxy-2-methyl-2H-1.2-benzothiazine 1,1 -dioxide, 20.6 g (0.21 mol) of 3-amino-5-methylisoxazole, and 2,500 ml of xylene was refluxed for 24 hours in a Soxhiet apparatus, the thimble of which contained 60 g of Linde type 4A molecular sieve. The mixture was cooled to 25°C and the resulting crystalline precipitate was collected and washed with ether to give 44 g of crude product. Recrystallization from 1,6(X) ml of 1,4-dioxan gave 34.7 g of material, MP 265°C to 271°C dec. 

When attaching clips, the rope length to be turned back when making a loop is dependent upon the rope size and the load to be handled. The recommended lengths, as measured from the thimble base, are given in Table 4-33. The thimble should first be wired to the rope at the desired point and the rope then bent around the thimble and temporarily secured by wiring the two rope members together. 

To facilitate rapid solution of oxygen from air bubbles it is desirable to make these as small as possible, e.g. by having the air enter through a porous thimble or sintered glass disc. Much less satisfactory results are secured by simply letting air escape into the solution from a tube drawn to a fine tip. 

Sampling Procedure. The sample extraction technique previously described was used in this work (8). However, a heated palladium thimble was also used to separate hydrogen and hydrocarbon fractions of the samples. No exchange occurred during the separation process in agreement with observations of other workers (30). In experiments using NH3 as a minor additive, the ammonia fraction was separated by means of appropriate cold traps. 

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