5.1 The magnitude of the hydroperoxide number is an indication of the quantity of oxidizing constituents present. Deterioration of the fuels results in the formation of hydroperoxides and other oxygen-carrying compounds. The hydroperoxide number measures those compounds that will oxidize potassium iodide.5.2 The determination of the hydroperoxide number of aviation turbine fuels, gasoline and diesel is significant because of the adverse effect of hydroperoxide upon certain elastomers in the fuel systems.5.3 The determination of hydroperoxide number of gasoline is significant because hydroperoxides have been demonstrated to decrease both Research and Motor Octane Numbers. In addition, hydroperoxides have adverse effects on certain fuel system components.5.4 The determination of hydroperoxide number of diesel fuel is significant because hydroperoxides have been demonstrated to increase the Cetane Number. In addition, hydroperoxides have adverse effects on certain fuel system components.1.1 This test method covers the determination of the hydroperoxide content expressed as hydroperoxide number of aviation turbine, gasoline and diesel fuels.1.2 The range of hydroperoxide number included in the precision statement is 0 mg/kg to 50 mg/kg active oxygen as hydroperoxide.1.3 The interlaboratory study to establish the precision of this test method consisted of spark-ignition engine fuels (regular, premium and California Cleaner-Burning gasoline), aviation gasoline, jet fuel, ultra low sulfur diesel, and biodiesel. However, biodiesel was not included in the precision calculation because of the large differences in results within labs and between labs.1.4 This test method detects hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide. It does not detect sterically-hindered hydroperoxides such as dicumyl and di-t-butyl hydroperoxides1.5 Di-alkyl hydroperoxides added commercially to diesel fuels are not detected by this test method.1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see 7.3, 7.6, 9.2, and Annex A1.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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2.1 This test method is intended for use in the determination of the acidity as free fatty acids in the absence of ammonium or triethanolamine soaps in sulfonated and sulfated oils for the purpose of quality assurance.1.1 This test method covers the determination of the acidity as free fatty acids existing in a sample of sulfonated or sulfated oil, or both, by titrating the sample dissolved in a solvent. It is not applicable in the presence of ammonium or triethanolamine soaps or salts or other compounds that do not react neutral to phenolphthalein when dissolved in alcohol.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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The magnitude of the peroxide number is an indication of the quantity of oxidizing constituents present. Deterioration of petroleum wax results in the formation of peroxides and other oxygen-carrying compounds. The peroxide number measures those compounds that will oxidize potassium iodide.1.1 This test method covers the determination of the peroxide number of petroleum wax.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 This test method measures the acid number of oils obtained from laboratory oxidation tests using smaller amounts of sample than Test Methods D974 or D664. It has specific application in Test Method D943 in which small aliquots of oil are periodically removed for testing by Test Method D3339. This test method, therefore, provides a means of monitoring the relative oxidation of oils, by measuring changes in acid number, at different time intervals and under the various oxidizing test conditions.1.1 This test method covers the determination of acidic constituents in new or used petroleum products and lubricants soluble or nearly soluble in mixtures of toluene, and isopropyl alcohol. The test method is especially intended for cases in which the amount of sample available to be analyzed is too small to allow accurate analysis by Test Methods D974 or D664. It is applicable for the determination of acids having dissociation constants in water larger than 10−9. Extremely weak acids having dissociation constants smaller than 10−9 do not interfere. Salts titrate if their hydrolysis constants are larger than 10−9.1.2 This test method can be used to indicate relative changes in acid number that occur in an oil during use under oxidizing conditions. Although the titration is made under definite equilibrium conditions, the method does not measure an absolute acidic property that can be used to predict performance of an oil under service conditions. No general relationship between bearing corrosion and acid number is known.1.3 Since this test method requires substantially less sample than Test Methods D974 or D664, it provides an advantageous means of monitoring an oxidation test by changes in acid number by (1) minimizing test sample depletion for acid number analyses and thus minimizing the disturbance of the test or (2) allowing additional acid number analyses to be made while maintaining the same test sample depletion and thus providing additional data.NOTE 1: Some oils, such as many cutting oils, rust-proofing oils, and similar compounded oils, or excessively dark-colored oils, may be more difficult to analyze by this test method due to obscurity of the color-indicator end point. These oils can be analyzed by Test Method D664 provided sufficient sample is available. However, this situation is much less likely using Test Method D3339 than using Test Method D974 due to the use of a more highly dilute sample during the titration and due to the greater stability of the end point color change. The acid numbers obtained by Test Method D3339 may or may not be numerically the same as those obtained by Test Method D664 but they should be of the same order of magnitude.NOTE 2: The results obtained using this method have been found to be numerically the same as those obtained using Test Method D974, within the precision of the two methods, for new or oxidized lubricants of the type primarily intended for hydraulic or steam turbine type service. The oxidized lubricants were obtained using the Test Method D943 oxidation test. This correlation is shown by the correlation coefficient r = 0.989 with slope s = + 1.017 and intercept y = + 0.029, calculated using the acid numbers obtained using both titration methods for the samples used for the precision statement (12.2).21.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see Sections 7 and 9, A1.1.4, A2.3.1, and A2.10.1.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 This test method is intended for use in the determination of the acid number of sulfonated and sulfated oils for the purpose of quality assurance.1.1 This test method covers determination of the acidity as free fatty acids in the presence of ammonium or triethanolamine soaps, or both, existing in a sample of sulfonated or sulfated oil, or both, by calculation from the total alkalinity and free-and-alkali combined fatty acids.1.2 The values stated in SI units are to be regarded as standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Petroleum products can contain additives that react with alkali to form metal soaps. Fats are examples of such additives. Also, certain used engine oils, especially from turbine or internal combustion engines, can contain chemicals that will similarly react with alkali. The saponification number expresses the amount of base that will react with 1 g of sample when heated in a specific manner. This then gives an estimation of the amount of acid present in the sample, that is, any free acid originally present plus any combined (for example, in esters) that have been converted to metal soaps during the heating procedure.5.2 Saponification numbers are also used in setting product specifications for lubricants and additives.1.1 These test methods cover the determination of the amount of constituents in petroleum products such as lubricants, additives, and transmission fluids that will saponify under the conditions of the test.NOTE 1: Statements defining this test and its significance when applied to electrical insulating oils of mineral origin will be found in Guide D117. Experience has shown that for transformer oils, Test Method D94, modified by use of 0.1 M KOH solution and 0.1 M HCl, is more suitable.1.1.1 Two test methods are described: Method A—Color Indicator Titration (Sections 6 – 13), and Method B—Potentiometric Titration (Sections 14 – 23).1.2 Because compounds of sulfur, phosphorus, the halogens, and certain other elements that are sometimes added to petroleum products also consume alkali and acids, the results obtained indicate the effect of these extraneous materials in addition to the saponifiable material present. Results on products containing such materials, on used internal-combustion-engine crankcase oils, and on used turbine oils must be interpreted with caution.NOTE 2: The materials referred to above, which are not normally considered saponifiable matter, include inorganic or certain organic acids, most nonalkali soaps, and so forth. The presence of such materials increases the saponification number above that of fatty saponifiable materials for which the test method is primarily intended. The odor of hydrogen sulfide near the end of the back-titration in the saponification test is an indication that certain types of reactive sulfur compounds are present in the sample. In the case of other reactive sulfur, chlorine, and phosphorus compounds and other interfering materials, no simple indication is given during the test. A gravimetric determination of the actual amount of fatty acids is probably the most reliable method for such compounds. Test Methods D128 or IP Method 284/86 can be used to determine fatty acids gravimetrically.1.3 The values stated in SI units are to be regarded as the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Sections 6, 7, 8, 10, 15, 16, 17, and 19.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Test Method D6612 for yarn number and yarn number variability is satisfactory for acceptance of commercial shipments and is used in the trade.5.1.1 If there are differences of practical significance between the reported test results for two or more laboratories, comparative tests should be performed by those laboratories to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, samples used for each comparative tests should be as homogeneous as possible, drawn from the same lot of material as the samples that results in disparate results during initial testing, and randomly assigned in equal numbers to each laboratory. Other fabrics with established tests values are used for this purpose. The test results from the laboratories involved should be compared appropriate statistical analysis and a probability level chosen by the two parties before testing begins, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results adjusted in consideration of the known bias.5.1.2 The average results from the two laboratories should be compared using appropriate statistical analysis and a probability level chosen by the two parties before the testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and the supplier must agree to interpret future test results with consideration to the known bias.5.2 Test Method D6612 also is used for the quality control of filament yarns.5.3 Indices of Variability: 5.3.1 Coefficient of Variation—%CV is a standard statistical calculation and is the most common index of yarn unevenness. For most textile applications in the 80 to 330 dtex (70 to 300 denier) range, a 1.0 to 1.3 %CV is adequate. %CV of yarns coarser than 666 dtex (600 denier) is not routine and usually not meaningful. %CV is less discriminating that %DS.5.3.2 Bad/Good Test—%BGT, which will normally be up to 20 % greater than %DS value, emphasizes the greatest spread in the entire length tested, (%DS is an average). If the value is greater than 50 % of the %DS, it suggests that there is a process that needs to be investigated.5.3.3 Density Spread—%DS is equivalent to the Uster % unevenness (Test Method D1425) and is an indication of short-term variability. Yarns with extreme values are more likely to cause trouble in subsequent yarn processes, which makes this perhaps the most useful index. The minimum achievable and maximum tolerance spread for a yarn product will depend on the yarn manufacturing process and end use. A spread of 3 to 4 % generally is, for most textile applications, in the range of 160 to 550 dtex (150 to 500 deniers). More critical applications, such as those using finer yarns, may require lower values.5.3.4 Density Frequency Variability—DFV is an index of spacing variability, whereas the others are indices of magnitude or unevenness. Frequency variability can induce resonance in high-speed processing and is a common source of barre, dye streaks, or patterned unevenness in fabrics.1.1 This test method covers the measurement of yarn number up to 4000 dtex (3600 denier) and related variability properties of filament and spun yarns using an automated tester with capability for measuring mass variability characteristics.1.2 Yarn number variability properties include percent density spread (%DS), coefficient of variation (%CV), density frequency variation.NOTE 1: For determination of yarn number by use of reel and balance, refer to Test Method D1907. For another method of measuring variability (unevenness) in yarn, refer to Test Method D1425.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore to ensure conformance with this standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The iodine adsorption number is useful in characterizing carbon blacks. It is related to the surface area of carbon blacks and is generally in agreement with nitrogen surface area. The presence of volatiles, surface porosity, or extractables will influence the iodine adsorption number. Aging of carbon black can also influence the iodine number.1.1 This test method covers the determination of the iodine adsorption number of carbon black.1.1.1 Method A is the original test method for this determination and Method B is an alternate test method using automated sample processing and analysis.1.2 The iodine adsorption number of carbon black has been shown to decrease with sample aging. Iodine Number reference materials have been produced that exhibit stable iodine number upon aging. One or more of these reference materials are recommended for daily monitoring (x-charts) to ensure that the results are within the control limits of the individual reference material. Use all Iodine Number reference materials from a set for standardization of iodine testing (see Section 8) when target values cannot be obtained.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Research O.N. correlates with commercial automotive spark-ignition engine antiknock performance under mild conditions of operation.5.2 Research O.N. is used by engine manufacturers, petroleum refiners and marketers, and in commerce as a primary specification measurement related to the matching of fuels and engines.5.2.1 Empirical correlations that permit calculation of automotive antiknock performance are based on the general equation:Values of k1, k2, and k3 vary with vehicles and vehicle populations and are based on road-O.N. determinations.5.2.2 Research O.N., in conjunction with Motor O.N., defines the antiknock index of automotive spark-ignition engine fuels, in accordance with Specification D4814. The antiknock index of a fuel approximates the Road octane ratings for many vehicles, is posted on retail dispensing pumps in the U.S., and is referred to in vehicle manuals.This is more commonly presented as:5.2.3 Research O.N. is also used either alone or in conjunction with other factors to define the Road O.N. capabilities of spark-ignition engine fuels for vehicles operating in areas of the world other than the United States.5.3 Research O.N. is used for measuring the antiknock performance of spark-ignition engine fuels that contain oxygenates.5.4 Research O.N. is important in relation to the specifications for spark-ignition engine fuels used in stationary and other nonautomotive engine applications.1.1 This laboratory test method covers the quantitative determination of the knock rating of liquid spark-ignition engine fuel in terms of Research O.N., including fuels that contain up to 25 % v/v of ethanol. However, this test method may not be applicable to fuel and fuel components that are primarily oxygenates.2 The sample fuel is tested using a standardized single cylinder, four-stroke cycle, variable compression ratio, carbureted, CFR engine run in accordance with a defined set of operating conditions. The O.N. scale is defined by the volumetric composition of PRF blends. The sample fuel knock intensity is compared to that of one or more PRF blends. The O.N. of the PRF blend that matches the K.I. of the sample fuel establishes the Research O.N.1.2 The O.N. scale covers the range from 0 to 120 octane number but this test method has a working range from 40 to 120 Research O.N. Typical commercial fuels produced for spark-ignition engines rate in the 88 to 101 Research O.N. range. Testing of gasoline blend stocks or other process stream materials can produce ratings at various levels throughout the Research O.N. range.1.3 The values of operating conditions are stated in SI units and are considered standard. The values in parentheses are the historical inch-pound units. The standardized CFR engine measurements continue to be in inch-pound units only because of the extensive and expensive tooling that has been created for this equipment.1.4 For purposes of determining conformance with all specified limits in this standard, an observed value or a calculated value shall be rounded “to the nearest unit” in the last right-hand digit used in expressing the specified limit, in accordance with the rounding method of Practice E29.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see Section 8, 14.4.1, 15.5.1, 16.6.1, Annex A1, A2.2.3.1, A2.2.3.3 (6) and (9), A2.3.5, X3.3.7, X4.2.3.1, X4.3.4.1, X4.3.9.3, X4.3.11.4, and X4.5.1.8.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Motor O.N. correlates with commercial automotive spark-ignition engine antiknock performance under severe conditions of operation.5.2 Motor O.N. is used by engine manufacturers, petroleum refiners and marketers, and in commerce as a primary specification measurement related to the matching of fuels and engines.5.2.1 Empirical correlations that permit calculation of automotive antiknock performance are based on the general equation:Values of k1, k2, and k3 vary with vehicles and vehicle populations and are based on road-octane number determinations.5.2.2 Motor O.N., in conjunction with Research O.N., defines the antiknock index of automotive spark-ignition engine fuels, in accordance with Specification D4814. The antiknock index of a fuel approximates the road octane ratings for many vehicles, is posted on retail dispensing pumps in the United States, and is referred to in vehicle manuals.This is more commonly presented as:5.3 Motor O.N. is used for measuring the antiknock performance of spark-ignition engine fuels that contain oxygenates.5.4 Motor O.N. is important in relation to the specifications for spark-ignition engine fuels used in stationary and other nonautomotive engine applications.5.5 Motor O.N. is utilized to determine, by correlation equation, the Aviation method O.N. or performance number (lean-mixture aviation rating) of aviation spark-ignition engine fuel.71.1 This laboratory test method covers the quantitative determination of the knock rating of liquid spark-ignition engine fuel in terms of Motor octane number, including fuels that contain up to 25 % v/v of ethanol. However, this test method may not be applicable to fuel and fuel components that are primarily oxygenates.2 The sample fuel is tested in a standardized single cylinder, four-stroke cycle, variable compression ratio, carbureted, CFR engine run in accordance with a defined set of operating conditions. The octane number scale is defined by the volumetric composition of primary reference fuel blends. The sample fuel knock intensity is compared to that of one or more primary reference fuel blends. The octane number of the primary reference fuel blend that matches the knock intensity of the sample fuel establishes the Motor octane number.1.2 The octane number scale covers the range from 0 to 120 octane number, but this test method has a working range from 40 to 120 octane number. Typical commercial fuels produced for automotive spark-ignition engines rate in the 80 to 90 Motor octane number range. Typical commercial fuels produced for aviation spark-ignition engines rate in the 98 to 102 Motor octane number range. Testing of gasoline blend stocks or other process stream materials can produce ratings at various levels throughout the Motor octane number range.1.3 The values of operating conditions are stated in SI units and are considered standard. The values in parentheses are the historical inch-pounds units. The standardized CFR engine measurements continue to be in inch-pound units only because of the extensive and expensive tooling that has been created for this equipment.1.4 For purposes of determining conformance with all specified limits in this standard, an observed value or a calculated value shall be rounded “to the nearest unit” in the last right-hand digit used in expressing the specified limit, in accordance with the rounding method of Practice E29.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For more specific hazard statements, see Section 8, 14.4.1, 15.5.1, 16.6.1, Annex A1, A2.2.3.1, A2.2.3.3(6) and (9), A2.3.5, X3.3.7, X4.2.3.1, X4.3.4.1, X4.3.9.3, X4.3.12.4, and X4.5.1.8.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 An estimate of TA purity can be determined by titrating with KOH. As an index of TA purity, the acid number can be used as a guide in the quality control of TA production.1.1 This test method covers the determination of acid number in terephthalic acid (TA) by automatic potentiometric titration. As the index of TA purity, acid number is usually within 674 to 676 mg KOH/g.1.2 In determining the conformance of the test results using this method, results shall be rounded off in accordance with the rounding-off method of Practice E29.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Crude oils and oil sands bitumen contain naturally occurring acidic species. Acidity of crude oil has been implicated in corrosion of distribution and process systems. The relative amount of these materials can be determined by titrating with bases. The acid number is a measure of this amount of acidic substance in the oil under the conditions of the test.5.2 Acid number of crude and distilled petroleum fractions has been measured by Test Method D664. Test Method D664 was developed for the analysis of lubricants and biodiesel. The titration solvent used in Test Method D664 does not properly address dissolving difficult samples such as crude oil, bitumen, and high wax samples addressed in this test method. Refer to Appendix X1.5.3 Test Method D974 is also not applicable to measuring acidity of crudes and highly colored samples because the indicator is not visible or it is difficult to discern a color change to detect the end point of the titration.1.1 This test method covers the determination of acidic components in crude oil and petroleum products including waxes, bitumen, base stocks, and asphalts that are soluble in mixtures of xylenes and propan-2-ol. It is applicable for the determination of acids whose dissociation constants in water are larger than 10–9; extremely weak acids whose dissociation constants are smaller than 10–9 do not interfere. The values obtained by this test method may not be numerically equivalent to other acid value measurements. The range of KOH acid numbers included in the precision statement is 0.1 mg/g to 16 mg/g.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Some specific hazards statements are given in Section 7 on Safety Precautions.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Computer simulation is known to be a very powerful analytical tool for both practitioners and researchers in the area of wood products and their applications in structural engineering. Complex structural systems can be analyzed by computer with the computer generating the system components, given the probability distribution of each component. Frequently the components are single boards for which a compatible set of strength and stiffness properties are needed. However, the entire structural simulation process is dependent upon the adequacy of the standard uniform number generator required to generate random observations from prescribed probability distribution functions.4.2 The technological capabilities and wide availability of microcomputers has encouraged their increased use for simulation studies. Tests of random number generators in commonly available microcomputers have disclosed serious deficiencies (1).3 Adequacy may be a function of intended end-use. This practice is concerned with generation of sets of random numbers, as may be required for simulations of large populations of material properties for simulation of complex structures. For more demanding applications, the use of packaged and pretested random number generators is encouraged.1.1 This practice gives a minimum testing procedure of computer generation routines for the standard uniform distribution. Random observations from the standard uniform distribution, RU, range from zero to one with every value between zero and one having an equal chance of occurrence.1.2 The tests described in this practice only support the basic use of random number generators, not their use in complex or extremely precise simulations.1.3 Simulation details for the normal, lognormal, 2-parameter Weibull and 3-parameter Weibull probability distributions are presented.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.See specific warning statement in 5.5.3.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 This test method determines the total acidity of trichlorotrifluoroethane by titration with alcoholic potassium hydroxide using phenolphthalein for an indicator.3.2 This test method can be used to develop production and purchasing specifications.1.1 This test method covers the determination of total acidity in trichlorotrifluoroethane and other halocarbons that are liquid at room temperature.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 6.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 An estimate of TA purity can be determined by titrating with KOH. As an index of TA purity, the acid number can be used as a guide in the quality control of TA production.1.1 This test method covers the determination of acid number of terephthalic acid (TA) by color-indicator titration. Acid number of TA product is usually within 674 to 676 mg KOH/g.1.2 In determining the conformance of the test results using this method, results shall be rounded off in accordance with the rounding-off method of Practice E29.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车