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Apparatus and Procedure

The general reaction procedure and apparatus used are exactly as described in Procedure 2. Ammonia (465 ml) is distilled into a 2-liter reaction flask and to this is added 165mlofisopropylalcoholandasolutionof30g(0.195 mole) of 17/ -estradiol 3-methyl ether (mp 118.5-120°) in 180 ml of tetrahydrofuran. The steroid is only partially soluble in the mixture. A 5 g portion of sodium (26 g, 1.13 g-atoms total) is added to the stirred mixture and the solid dissolves in the light blue solution within several min. As additional metal is added, the mixture becomes dark blue and a solid (matted needles) separates. Stirring is inefficient for a few minutes until the mass of crystals breaks down. All of the sodium is consumed after 1 hr and 120 ml of methanol is then added to the mixture with care. The product is isolated as in Procedure 4h 2. After being air-dried, the solid weighs 32.5 g (ca. 100% for a monohydrate). A sample of the material is dried for analysis and analyzed as described in Procedure 2 enol ether, 91% unreduced aromatics, 0.3%. The crude product may be crystallized from acetone-water or preferably from hexane. [Pg.50]

This technique allows the selective electro-deposition of a metal from a solution in the presence of ions of a less noble metal, provided that there is a sufficient difference between their standard reduction potentials the latter condition suggests remaining on the safe side (less negative) with the cathodic potential, so that the analysis may lose much in velocity on the other hand, the simplicity of procedure and apparatus is an advantage. [Pg.229]

All of the tests to investigate the oxidizing properties of substances involve a conical pile or a horizontal strip type of burning procedure and apparatus [134, 136, 157, 158]. The substance is mixed with a known dried combustible material such as sawdust, cellulose, or sugar, in various ratios. The burning velocity of a horizontal strip or the burning time of a conical pile of the mixture... [Pg.87]

Figure 15.19a shows the typical experimental procedure and apparatus for catalyst preparation by SCCO2 treatment. For example, [Rh(OAc)2]2 and Pt(acac)2 were... [Pg.618]

Figure 15.19 (a) Schematic preparation procedure and apparatus for Rh and PtRh nanoparticle catalysts from Rh and PtRh salt-impregnated silicates by super critical fluid CO2 treatment (b) phase diagram of super critical CO2 as functions of pressure and temperature. [Pg.620]

In Ref 3 is also described on pp 29-31 the so-called Reactivity Test. The purpose of this test is to determine which materials might cause deterioration, or even hazard, when brought in contact (ot stored together) with the explosive to test. The test involves the same procedure and apparatus as the vacuum stability test at 100°. A detailed description of the procedure is given on pp 30-31 of Ref 3... [Pg.574]

The procedures and apparatus for the preparation of high-purity trimethylgallium are essentially the same as those employed for the preparation of trimethylindium (as described in Section 7.A, parts a, c, and d), and only the additional pertinent facts relating to the preparation of trimethylgallium are given here. [Pg.46]

The procedures and apparatus for the preparation of the diethyl ether solution of dimethylzinc and the dissociation of the adduct are essentially the... [Pg.60]

The D2892 lab test is a rather difficult test to run, requiring extensive laboratory work and considerable specialized equipment. It is therefore most apparent that the simpler ASTM tests D86 and D1160 are preferred. No fractionator reflux is required. These ASTM distillations, compared to the more rigorous TBP tests, are more widely used. This is because the ASTM tests are simpler, less expensive, require less sample, and require approximately one-tenth as much time. Also, these ASTM tests are standardized, whereas TBP distillations vary appreciably in procedure and apparatus. [Pg.20]

CAL TB 117 Requirements, Test Procedures and Apparatus for Testing the Flame Retardance of Resilient Filling Materials Used in Upholstered Furniture. Bureau of Home Furnishings and Thermal Insulation, Sacramento, CA. EN 13501 Fire Classification of Construction Products and Building Elements - Part 1 - Classification Using Test Data from Reaction-to-Fire Tests. European Committee for Standardization, Brussels, Belgium. [Pg.382]

Requirements, test procedures, and apparatus for testing the resistance of a mattress or mattress pad to combustion which may result from a smoldering cigarette... [Pg.592]

Requirements, test procedure, and apparatus for testing the flame retardance of upholstered furniture... [Pg.592]

Draft TB 604 2007 Test procedure and apparatus for the open-flame resistance of filled bedclothing... [Pg.592]

If the procedure and apparatus of Hurd and Brimm are used for the production of the rhenium(V) chloride, the decomposition train, from point A to point B, is attached to the combustion tube in place of tubes D to I. The bottom of the combustion tube and the connecting tube of bulb 1... [Pg.195]

All the above-mentioned areas of research have only become possible due to the wonderful and creative application of analytical chemical techniques and purification procedures. Such procedures and apparatus are needed to detect small quantities of materials. They are also necessary for monitoring drug administration and effectiveness, and for analysis of breakdown products made in the body. [Pg.161]

E. W. Flosdorf and S. Mudd, Procedure and apparatus for preservation in lyophile form of serum and other biological substances, J. Immunol. 29 389 (1935). See also E. W. Flosdorf, Freezing and Drying, Reinhold, New York, 1949, pp. 1-280. [Pg.30]

Fig. 3 Diagram of the surgical procedure and apparatus for an in situ nasal recirculation study in rats. After an incision is made in the neck of the rats, the trachea is cannulated with a polyethylene tube to allow spontaneous breathing. Another tube, through which the drug solution is circulated, is inserted through the esophagus to the posterior part of the nasal cavity. The nasopalatine is closed with an adhesive cement to prevent drainage of the drug solution into the mouth. (Reprinted from Ref. with permission from Elsevier.)... Fig. 3 Diagram of the surgical procedure and apparatus for an in situ nasal recirculation study in rats. After an incision is made in the neck of the rats, the trachea is cannulated with a polyethylene tube to allow spontaneous breathing. Another tube, through which the drug solution is circulated, is inserted through the esophagus to the posterior part of the nasal cavity. The nasopalatine is closed with an adhesive cement to prevent drainage of the drug solution into the mouth. (Reprinted from Ref. with permission from Elsevier.)...
Determination. A procedure and apparatus for assay by hydrogen evolution are described in Metal Hydrides Technical Bulletin No. 401. [Pg.294]

Of interest is the range of application of the preparatively useful, catalytic oxidation with platinum at low temperatures in aqueous or organic solvents. The procedure and apparatus are similar to those used in cata-... [Pg.170]

The variation of known quantum yields is remarkable, however, ranging from greater than unity to less than 10 . Since there is no alternative available to experimental measurement of standardized and straightforward procedures and apparatus for measurement are needed by environmental chemists. [Pg.269]

Elemental analyses (C, H, N and ash) were carried out by combustion at 900°C, using a procedure and apparatus similar to that described in Stump and Frazer (1973). Carbon dioxide, nitrogen and hydrogen were purified, measured volumetrically, and sealed in Pyrex tubes for isotopic analysis. The sulfur content was determined by Galbraith Laboratories, Knoxville, Tennessee. The high sulfur values may in part reflect inorganic sulfide decomposition during pyrolysis (Table 2). [Pg.324]

Using the procedure and apparatus described in Section C Note the Cautioa in Section CX boron triiodide (1.13g, 2.9mmol) in hexane (lOmL) is added gradually to a stirred solution of [UCp"2Cl2] (2.10g, 2.9mmol) in C Hi4 (lOOmL) at 20°C. The mixture is stin at 20°C for 4h, filter and the filtrate is concentrated to 20 mL. Cooling the filtrate to — 30°C yields red cubes of [UCp"2l2] (4). Yield 2.17g (82%X which are washed with cold ( —78°C) C3H12 and dried in vacuo. For its characterization, see Table I. [Pg.176]


See other pages where Apparatus and Procedure is mentioned: [Pg.51]    [Pg.55]    [Pg.172]    [Pg.30]    [Pg.50]    [Pg.61]    [Pg.104]    [Pg.103]    [Pg.837]    [Pg.176]    [Pg.197]    [Pg.130]    [Pg.306]    [Pg.123]    [Pg.401]    [Pg.830]    [Pg.163]    [Pg.14]    [Pg.68]    [Pg.103]   
See also in sourсe #XX -- [ Pg.189 , Pg.190 ]




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