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Description of Procedures

Depending upon the sample size, the NE treatment may be conducted in a stainless steel autoclave which is conveniently made from a stainless steel tube of appropriate size fitted with screw caps (stainless steel) at both ends. For the sample size (—28 mg) described later, the autoclave is made from a 0.6 cm (diam.) x 7.5cm (length) stainless steel tube. The autoclave is heated in an oil bath or comparable device in which the temperature can be controlled to 1—2°C and which is provided with a means of shaking the autoclave continuously during the reaction. The detailed procedure is described below. [Pg.378]

Accurately weigh approximately 28 mg of extractive- and moisture-free wood meal into the autoclave and add two small stainless steel balls. For each 28 mg of wood meal, 1ml of reagent is added. The autoclave is sealed, shaken manually for about 5 min, then heated at 180 1—2°C for 4h. The autoclave is shaken continuously throughout the heating operation. [Pg.378]

At the end of the reaction, the autoclave is removed from the heat source and cooled in a cold water bath. One of the caps is removed and the autoclave contents are carefully poured into an 80-ml beaker. A small amount of ethyl ether is added to the autoclave and the residual material on the wall is scraped with a thin spatula. This solution is also added to the 80-ml beaker. This procedure is repeated until the washings become clear. The cap at the other end of the autoclave is removed and both caps are washed with ethyl ether which is combined with the other ether washings. [Pg.378]

5-ml portion of an internal solution (5 mg of bibenzyl/ml benzene) is added to the combined reaction solution and washings in the 80-ml beaker and filtered through a glass filter paper which subsequently is washed several times with ethyl ether. The combined filtrate and washings from this operation are transferred to a separatory funnel and a NaCI-saturated aqueous solution is added to deactivate the boron trifluoride. The funnel is shaken vigorously and the ether layer is removed and concentrated to about 10 ml by film evaporation. The concentrate is transferred to a glass vial fitted with a Teflon-lined cap and dried overnight over anhydrous sodium sulfate. [Pg.378]

05-ml aliquot of the dried ether solution is pipetted into a small glass vial containing a few drops of pyridine and 0.1 ml of N,0-bis(trimethylsilyl)acetamide (Pierce Chemicals). The vial is stoppered with a Teflon-lined cap and the TMS derivatization is performed at room temperature for 1 h. The TMS derivatives are separated and determined by gas chromatography. [Pg.378]


Equally precise and meticulous as an experimentalist, he devoted time during his days at Pittsburgh to write comprehensive articles on such practical techniques as crystallization, vacuum distillation, and sublimation, which were published in the Weissberger Techniques of Organic Chemistry series. His preoccupation with careful experimental techniques and then-accurate recording in the literature remained with him always. He abhorred vague descriptions of procedures, speculative interpretations not based on... [Pg.423]

An explanation of the purpose of the research and the expected duration of the participant s participation A description of procedures to be followed and identification of any procedures that are experimental, including all invasive procedures... [Pg.437]

Discussions of different PAGE systems and possible errors are given by Johnson. (Johnson G (1983) Gel Sieving electrophoresis a description of procedures and analysis of errors. In Glick D (ed.) Methods in biochemical analysis, vol 29. WUey, New York, p 25). [Pg.24]

More detailed description of procedures are given as Test No 114 in MIL-STD-331... [Pg.1096]

A detailed description of Bichel Closed Bomb employed in 1931 at USBurMines was given on pp 85—87 of Ref 1 (under the name Bichel Gage), together with description of procedure used at that time. The Fig shown on p 86 of Ref 1 is just a photo of exterior view, A clearer idea of construction can be obtd from Fig of Vol 3 of Ertcycl, p C331 R and from Fig on p C332-L... [Pg.675]

N 36.84%, OB to CO, -42.1%. Ndls(from ether), mp 38°, d 1.2433 at 48.6°, nD 1.46l62 at 48.6°(Ref 2) expl violently when heated in a capillary(Ref 5)- Easily sol in w, ale, chlf benz less sol in eth very si sol in petr eth. Was first prepd by Franchi-mont Be Kiobbie(Ref 2) by nitration and hydrolysis of me thy 1-N-me thy 1-car bam ate, CHjCO, NH CH,. Other methods are known (Refs 1 4). Johnson(Ref 5) prepd it in 66% yield by nitration and hydrolysis of ethyl-N-methy 1-carbamate. Detailed description of procedure is given. It is a powerful expl, with a Trauzl test value of 144%PA. Its toxicity is probably similar to that of amino-methane(qv)... [Pg.227]

Another illustration represents the (JS "Internal Crusher Gage Mil . A description of procedure used at Aberdeen Proving Ground, Md is given in Ref 7 3, PP 1 6. The usable range of measurement of this gage is 12 to 115 thousand psi with piston area 1/60 sq inches. [Pg.119]

AN (actual nitric) and N-so (nitroso). A brief description of procedures for detg these values is given under Acidity in Acids in Vol 1, pp A88-A9O... [Pg.465]

In the 2nd series of tests, the cold container with sample was suddenly plunged into a bath maintained at constant temp which was close to or slightly above t° Q, and the time interval before the ignition takes place (known as delay to ignition or induction period) was measured and the temp exprapolated to 5 sec period. Detailed description of procedures is given in Ref, pp 206-07... [Pg.476]

Short-term experiments of about 100 hr are designed to measure the initial rate of selection between two strains. As I use chemostats similar to those shown in Fig. 1, the following description of procedures will be in reference to this setup. [Pg.621]

This section should contain information on computer systems that control critical manufacturing processes. The developer of the system should be identified and information provided also should include a brief description of procedures for changes to the computer system. This section also should contain a validation summary for each of these systems and a certification that an IQ and OQ have been completed. [Pg.184]

Johnson, George, Gel Sieving Electrophores A Description of Procedures... [Pg.241]

Electrophoresis, Gel Sieving A Description of Procedures and Analysis of Errors... [Pg.253]

In addition to descriptions of procedures to be followed, the quality system must provide for the creation and maintenance of records which show what has been done. This is necessary to enable the laboratory to replicate, if required, the analytical process that was performed for a particular sample. The process of audit is only possible if adequate records are maintained and the absence of adequate records will constitute a non-compliance with most quality management standards (see Section 5.2). [Pg.64]

Oxidation of iodide ion has enjoyed popularity largely as a test of theories of salt effects. Studies of the rates in mainly aqueous solutions " and in mixed solvents provide good examples of struggles with insufficient sensitivity (here of the starch, iodine, iodide system), with persistent catalytic impurities, with inadequate or inaccurate description of procedures and results and with repetition which became necessary because of lack of standardization of conditions, all of which cause frequent frustration in kinetic investigations. The... [Pg.351]


See other pages where Description of Procedures is mentioned: [Pg.308]    [Pg.146]    [Pg.515]    [Pg.1092]    [Pg.1093]    [Pg.218]    [Pg.531]    [Pg.568]    [Pg.218]    [Pg.528]    [Pg.105]    [Pg.568]    [Pg.250]    [Pg.336]    [Pg.27]    [Pg.378]    [Pg.425]    [Pg.227]    [Pg.568]    [Pg.227]    [Pg.568]    [Pg.204]    [Pg.315]    [Pg.526]    [Pg.361]    [Pg.259]   


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