Standards apparatus section

Supersaturation results, as noted above, from boiling in the crystallizer. Figure 7.86 shows that Glauber s salt is the stable solid phase only at reduced temperature. The system therefore runs under vacuum, provided by any standard apparatus (Section 12.6.1). Evaporation of water cools the liquor into the desired temperature range. 

Most Cone Calorimeters include instrumentation for measuring light extinction in the exhaust duct, using a laser light source, described in ASTM E 1354 and ISO 5660-2 (Section 14.3.5.3.2). Instrumentation to measure concentrations of soot, carbon dioxide, carbon monoxide, and other gases are commonly added. Some laboratories have used a modified version of the standard apparatus to conduct studies in vitiated or oxygen enriched atmospheres.43 50... 

The General Tests, Processes, and Apparatus section contains 60 test methods, such as fluorometry and electrometric titration, dissolution and disintegration tests, content uniformity, and a bacterial endotoxin test. Qualitative tests, reagents and test solutions, and standard solutions are also included. The Infrared Reference Spectra of 124 chemical entities are included in an appendix and will be updated in subsequent editions. 

The AO AC standardized a lot of procedures based on TLC that were validated by collaborative studies and met the AO AC requirements regarding performance criteria. The AOAC standards provide detailed information on the apparatus, the reagents, the preparation of standards, and the sampling. A selection of these methods and the most recent ones are quoted in the standard procedures section. 

Although the yields with the above simple apparatus may not be quite so high as can be obtained with the purely semimicro apparatus described in Sections XII,1 and XII,2, the numerous advantages attending the purchase of standard (and therefore comparatively inexpensive) apparatus usually outweigh the small reduction in yield. 

Laboratory tests used in the development of inhibitors can be of various types and are often associated with a particular laboratory. Thus, in one case simple test specimens, either alone or as bimetallic couples, are immersed in inhibited solutions in a relatively simple apparatus, as illustrated in Fig. 19.34. Sometimes the test may involve heat transfer, and a simple test arrangement is shown in Fig. 19.35. Tests of these types have been described in the literatureHowever, national standards also exist for this type of test approach. BSl and ASTM documents describe laboratory test procedures and in some cases provide recommended pass or fail criteria (BS 5117 Part 2 Section 2.2 1985 BS 6580 1985 ASTM 01384 1987). Laboratory testing may involve a recirculating rig test in which the intention is to assess the performance of an inhibited coolant in the simulated flow conditions of an engine cooling system. Although test procedures have been developed (BS 5177 Part 2 Section 2.3 1985 ASTM 02570 1985), problems of reproducibility and repeatability exist, and it is difficult to quote numerical pass or fail criteria. 

The Dafert pipette (Fig. 3.2 Section 3.11) is a convenient apparatus for dispensing fixed volumes of a standard solution, as are also the various liquid dispensers which are available. 

The location of the position of double bonds in alkenes or similar compounds is a difficult process when only very small amounts of sample are available [712,713]. Hass spectrometry is often unsuited for this purpose unless the position of the double bond is fixed by derivatization. Oxidation of the double bond to either an ozonide or cis-diol, or formation of a methoxy or epoxide derivative, can be carried out on micrograms to nanograms of sample [713-716]. Single peaks can be trapped in a cooled section of a capillary tube and derivatized within the trap for reinjection. Ozonolysis is simple to carry out and occurs sufficiently rapidly that reaction temperatures of -70 C are common [436,705,707,713-717]. Several micro-ozonolysis. apparatuses are commercially available or can be readily assembled in the laboratory using standard equipment and a Tesla coil (vacuum tester) to generate the ozone. Reaction yields of ozonolysis products are typically 70 to 95t, although structures such as... 

The application of electroanalysis in non-aqueous media to a certain analytical problem requires a well considered selection of the solvent together with a suitable electroanalytical method, which can be carried out on the basis of the solvent classes mentioned in Table 4.3 and of the related theories. The steps to be taken include the preparation of the solvent and the apparatus for the electroanalytical method proper, together with other chemicals, especially when the method includes titration. Much detailed information on the purification of the solvents and on the preparation of titrants and primary standards can be found in the references cited in Section 4.1 and in various commercial brochures1,84,85 and books17,86-89 we shall therefore confine ourselves to some remarks on points of major importance. 

Further, the apparatus must be marked according to the requirements of Section 2 of Chapter 4 of the standard. 

Section 1-4.1. Reprinted with permission from NFPA 493-1978, Standard for Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division 1 Hazardous Locations, Copyright 1979, National Fire Protection Association, Quincy, MA 02269. This reprinted material is not the complete and offical position of the NFPA on the referenced subject, which is represented only by the standard in its entirety. 

Part—I has three chapters that exclusively deal with General Aspects of pharmaceutical analysis. Chapter 1 focuses on the pharmaceutical chemicals and their respective purity and management. Critical information with regard to description of the finished product, sampling procedures, bioavailability, identification tests, physical constants and miscellaneous characteristics, such as ash values, loss on drying, clarity and color of solution, specific tests, limit tests of metallic and non-metallic impurities, limits of moisture content, volatile and non-volatile matter and lastly residue on ignition have also been dealt with. Each section provides adequate procedural details supported by ample typical examples from the Official Compendia. Chapter 2 embraces the theory and technique of quantitative analysis with specific emphasis on volumetric analysis, volumetric apparatus, their specifications, standardization and utility. It also includes biomedical analytical chemistry, colorimetric assays, theory and assay of biochemicals, such as urea, bilirubin, cholesterol and enzymatic assays, such as alkaline phosphatase, lactate dehydrogenase, salient features of radioimmunoassay and automated methods of chemical analysis. Chapter 3 provides special emphasis on errors in pharmaceutical analysis and their statistical validation. The first aspect is related to errors in pharmaceutical analysis and embodies classification of errors, accuracy, precision and makes... 

Once the appropriate dissolution conditions have been established, the method should be validated for linearity, accuracy, precision, specificity, and robustness/ruggedness. This section will discuss these parameters only in relation to issues unique to dissolution testing. All dissolution testing must be performed on a calibrated dissolution apparatus meeting the mechanical and system suitability standards specified in the appropriate compendia. 

Less extensive than ISO/fEC 17025, section 4 of GLP states that all apparatus and materials should be appropriate for the tests, used in accordance with the SOPs, and calibrated, where appropriate, to national or international standards of measurement. Chemicals should be properly labeled, with expiration dates and available material safety data sheets. 

The performance verification of Karl Fisher apparatus should include checks for the accuracy and precision of the instrument. The linearity of the instrument should be determined at installation. The first step is to standardize the instrument (see Section 14.3.2) pure water is sufficient for this purpose. Sodium tartrate dihydrate standard (water content 15.66 0.05%) can be used to assess the accuracy, precision, and linearity of the instrument. Typically, one would measure the water content of at least five samples, over the intended instrument user range. For example, the water content of sodium tartrate dihydrate samples that were 65 mg (ca. 10 mg H20), 195 mg (ca. 30 mg H20), 325 mg (ca. 50 mg H20), 455 mg (ca. 70 mg H20), and 650 mg (100 mg H20) could be determined. Calculate the percent water to assess the instrument s accuracy. The results should be within 98 to 102% of 15.66% water. Determine the % RSD of the percent water found to assess the precision of the instrument. The % RSD should be less than or equal to 1%. Finally, plot the expected water content versus the percent water content to assess the linearity of the instrument s response. A correlation coefficient (r) value of 0.999 or greater is acceptable. 

This will be a very brief section because the present situation is that the only ISO, BS and ASTM standards to cover forced vibration dynamic apparatus are the guides 2 discussed earlier in the chapter, plus the ASTM moving die processability test covered in Chapter 6. 

The present ISO standard for creep is ISO 80131 which specifies procedures for measurements in compression and shear. In earlier standards, creep and stress relaxation were covered in the same documents and creep in tension was included. One reason for the separation was that stress relaxation became more important for seal performance, whereas creep remained a more minority interest. Measurements in tension were dropped on the basis that engineering components are not generally stressed in this manner. However, it is worth noting that, if a general indication of creep performance is required, the strains in tension can be relatively large and only quite simple apparatus is necessary. Such a simple method is included in the ISO standard for tension set described in Section 3.2. The British equivalent, BS903 Part A152 is identical to ISO 8013. 

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