5.1 The carbon distribution and ring content serve to express the gross composition of the heavier fractions of petroleum. These data can be used as an adjunct to the bulk properties in monitoring the manufacture of lubricating oil base stocks by distillation, solvent refining or hydrogenation, or both, and in comparing the composition of stocks from different crude sources. Furthermore, the data can often be correlated with critical product performance properties.1.1 This test method covers the calculation of the carbon distribution and ring content (Note 1) of olefin-free petroleum oils from measurements of refractive index, density, and molecular weight (n-d-M).2 This test method should not be applied to oils whose compositions are outside the following ranges:1.1.1 In terms of carbon distribution—up to 75 % carbon atoms in ring structure; percentage in aromatic rings not larger than 1.5 times the percentage in naphthenic rings.1.1.2 In terms of ring content—up to four rings per molecule with not more than half of them aromatic. A correction must be applied for oils containing significant quantities of sulfur.NOTE 1: The composition of complex petroleum fractions is often expressed in terms of the proportions of aromatic rings (RA), naphthene rings (RN), and paraffin chains (CP) that would comprise a hypothetical mean molecule. Alternatively, the composition may be expressed in terms of a carbon distribution, that is, the percentage of the total number of carbon atoms that are present in aromatic ring structures (% CA), naphthene ring structures (% CN), and paraffin chains (% Cp).1.2 The values stated in SI units are to be regarded as the standard.1.2.1 Exception—The values in parentheses are for information only.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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3.1 This practice may be used to determine non-protein or non-nitrogen containing organic matter in leather which is not extractable with water or hexane. Examples would be vegetable tannins and acrylic lubricants.1.1 This practice covers the determination of the combined tannin and nonextractable organic resins and the degree of tannage of all types of vegetable-tanned leather and leather with organic retannages. This practice does not apply to wet blue.1.2 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 Heat capacities obtained by this method are those at atmospheric pressure. However, because the temperature range is low, the calculated values are similar to saturated liquid heat capacities in the temperature-pressure range required for most engineering design.1.1 This test method covers the calculation of liquid heat capacity, Btu/lb · °F (kJ/kg · K), at atmospheric pressure, of petroleum fuels for which distillation data may be obtained in accordance with Test Method D86 without reaching a decomposition point prior to obtaining 90 % by volume distilled.1.2 This test method is not applicable at temperatures less than 0 °F (−18 °C) and greater than 60 °F (16 °C) above the volumetric average boiling point of the fuel.1.3 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.1.4 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 viscosity-gravity constant (VGC) is a useful function for the approximate characterization of the viscous fractions of petroleum.2 It is relatively insensitive to molecular weight and is related to a fluids composition as expressed in terms of certain structural elements. Values of VGC near 0.800 indicate samples of paraffinic character, while values close to 1.00 indicate a preponderance of aromatic structures. Like other indicators of hydrocarbon composition, the VGC should not be indiscriminately applied to residual oils, asphaltic materials, or samples containing appreciable quantities of nonhydrocarbons.1.1 This test method covers the calculation of the viscosity-gravity constant (VGC) of petroleum oils2 having viscosities in excess of 5.5 mm2/s at 40 °C (104 °F) and in excess of 0.8 mm2/s at 100 °C (212 °F).1.2 Annex A1 describes a method for calculating the VGC from Saybolt (SUS) viscosity and relative density.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3.1 The SI unit of kinematic viscosity is mm2/s.1.3.2 Exception—Fahrenheit temperature units are used in this practice because they are accepted by industry for the type of legacy conversions described in this practice.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 Permanent Shear Stability Index (PSSI) is a measure of the loss of viscosity, due to shearing, contributed by a specified additive.NOTE 2: For example, a PSSI of 50 means the additive will lose 50 % of the viscosity it contributes to the finished oil.5.2 The selection of appropriate base fluids and additive concentrations to be used in test oils is left to individual operators or companies. These choices will depend on the intended application for the additive.NOTE 3: PSSI may depend more strongly on base fluid, additive concentration, additive chemistry, and the presence of other additives for base fluids of unusual composition (for example, esters) or if additives outside the common range of chemistries and concentrations are used. Caution should be exercised when interpreting results from different sources.1.1 This practice specifies the procedure for the calculation of Permanent Shear Stability Index (PSSI) of an additive using viscosities before and after a shearing procedure.1.2 PSSI is calculated for a single blend component and can then be used to estimate the effects of that component on finished lubricant blends.1.3 This practice is applicable to many products and may use data from many different test methods. The calculation is presented in its most general form in order not to restrict its 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 Each power reactor has a specific DEX value that is their technical requirement limit. These values may vary from about 200 to about 900 μCi/g based upon the height of their plant vent, the location of the site boundary, the calculated reactor coolant activity for a condition of 1 % fuel defects, and general atmospheric modeling that is ascribed to that particular plant site. Should the DEX measured activity exceed the technical requirement limit, the plant enters an LCO requiring action on plant operation by the operators.5.2 The determination of DEX is performed in a similar manner to that used in determining DEI, except that the calculation of DEX is based on the acute dose to the whole body and considers the noble gases 85mKr, 85Kr, 87Kr, 88Kr, 131mXe, 133mXe, 133Xe, 135mXe, 135Xe, and 138Xe which are significant in terms of contribution to whole body dose.5.3 It is important to note that only fission gases are included in this calculation, and only the ones noted in Table 1. For example 83mKr is not included even though its half-life is 1.86 hours. The reason for this is that this radionuclide cannot be easily determined by gamma spectrometry (low energy X-rays at 32 and 9 keV) and its dose consequence is vanishingly small compared to the other, more prevalent krypton radionuclides.5.4 Activity from 41Ar, 19F, 16N, and 11C, all of which predominantly will be in gaseous forms in the RCS, are not included in this calculation.5.5 If a specific noble-gas radionuclide is not detected, it should be assumed to be present at the minimum-detectable activity. The determination of dose-equivalent Xe-133 shall be performed using effective dose-conversion factors for air submersion listed in Table III.1 of EPA Federal Guidance Report No. 12,3 or the average gamma-disintegration energies as provided in ICRP Publication 38 (“Radionuclide Transformations”) or similar source.1.1 This practice applies to the calculation of the dose equivalent to 133Xe in the reactor coolant of nuclear power reactors resulting from the radioactivity of all noble gas fission products.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, 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 The density/unit weight of a cohesionless soil may be determined by various in-place methods in the field or by the measurement of physical dimensions and masses by laboratory soil specimens. The dry density/unit weight of a cohesionless soil does not necessarily, by itself, reveal whether the soil is loose or dense.5.2 Relative density/unit weight expresses the degree of compactness of a cohesionless soil with respect to the loosest and densest condition as defined by standard laboratory procedures. Only when viewed against the possible range of variation, in terms of relative density/unit weight, can the dry density/unit weight be related to the compaction effort used to place the soil in a compacted fill or indicate volume change and stress-strain tendencies of soil when subjected to external loading.5.3 An absolute minimum density/unit weight is not necessarily obtained by these test methods.NOTE 1: In addition, there are published data to indicate that these test methods have a high degree of variability.4 However, the variability can be greatly reduced by careful calibration of equipment, and careful attention to proper test procedure and technique.5.4 The use of the standard molds (6.2.1) has been found to be satisfactory for most soils requiring minimum index density/unit weight testing. Special molds (6.2.2) shall only be used when the test results are to be applied in conjunction with design or special studies and there is not enough soil to use the standard molds. Such test results should be applied with caution, as minimum index densities/unit weights obtained with the special molds may not agree with those that would be obtained using the standard molds.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740, generally, are considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 These test methods cover the determination of the minimum-index dry density/unit weight of cohesionless, free-draining soils. The adjective “dry” before density or unit weight is omitted in the title and remaining portions of this standards to be be consistent with the applicable definitions given in Section 3 on Terminology.1.2 System of Units: 1.2.1 The testing apparatus described in this standard has been developed and manufactured using values in the gravimetric or inch-pound system. Therefore, test apparatus dimensions and mass given in inch-pound units are regarded as the standard.1.2.2 It is common practice in the engineering profession to concurrently use pounds to represent both a unit of mass (lbm) and a unit of force (lbf). This implicitly combines two separate systems of units; that is, the absolute system and the gravitational system. It is scientifically undesirable to combine the use of two separate sets of inch-pound units within a single standard. This test method has been written using the gravitational system of units when dealing with the inch-pound system. In this system, the pound (lbf) represents a unit of force (weight). However, balances or scales measure mass; and weight must be calculated. In the inch-pound system, it is common to assume that 1 lbf is equal to 1 lbm. While reporting density is not regarded as nonconformance with this standard, unit weights should be calculated and reported since the results may be used to determine force or stress.1.2.3 The terms density and unit weight are often used interchangeably. Density is mass per unit volume, whereas unit weight is force per unit volume. In this standard, density is given only in SI units. After the density has been determined, the unit weight is calculated in SI or inch-pound units, or both.1.3 Three alternative methods are provided to determine the minimum index density/unit weight, as follows:1.3.1 Method A—Using a funnel pouring device or a hand scoop to place material in mold.1.3.2 Method B—Depositing material into a mold by extracting a soil filled tube.1.3.3 Method C 2—Depositing material by inverting a graduated cylinder.1.4 The method to be used should be specified by the agency requesting the test. If no method is specified, the provisions of Method A shall govern. Test Method A is the preferred procedure for determining minimum index density/unit weight as used in conjunction with the procedures of Test Methods D4253. Methods B and C are provided for guidance of testing used in conjunction with special studies, especially where there is not enough material available to use a 0.100 ft3 (2830 cm3) or 0.500 ft3 (14 200 cm3) mold as required by Method A.1.5 These test methods are applicable to soils that may contain up to 15 %, by dry mass, of soil particles passing a No. 200 (75-μm) sieve, provided they still have cohesionless, free-draining characteristics (nominal sieve dimensions are in accordance with Specification E11).1.5.1 Method A is applicable to soils in which 100 %, by dry mass, of soil particles pass a 3-in. (75-mm) sieve and which may contain up to 30 %, by dry mass, of soil particles retained on a 11/2-inch (37.5-mm) sieve.1.5.2 Method B is applicable to soils in which 100 %, by dry mass, of soil particles pass a 3/4-inch (19.0-mm) sieve.1.5.3 Method C is applicable only to fine and medium sands in which 100 %, by dry mass, of soil particles pass a 3/8-in. (9.5-mm) sieve and which may contain up to 10 %, by dry mass, of soil particles retained on a No. 10 (2.00-mm) sieve.1.5.4 Soils, for the purposes of these test methods, shall be regarded as naturally occurring cohesionless soils, processed particles, or composites or mixtures of natural soils, or mixtures of natural and processed particles, provided they are free-draining.1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.6.1 For purposes of comparing a measured or calculated value(s) to specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal or significant digits in the specified limits.1.6.2 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 This test method allows the simultaneous determination of total nitrogen and total phosphorous from one sample digestion step. 5.2 This test method measures oxidized ammonia and organic nitrogen (as nitrate) and soluble nitrate simultaneously. By subtracting the nitrate + nitrite value from a non-digested sample gives a TKN: When using this test method: where: TN   =   total nitrogen, and TKN   =   total Kjeldahl nitrogen. 1.1 This test method is applicable for the analysis total nitrogen (organic nitrogen + ammonia-N + nitrate-N + nitrite-N) as nitrate and total phosphorus as orthophosphate in unfiltered water samples by alkaline persulfate digestion followed by ion chromatography (IC). 1.2 Total Kjeldahl nitrogen (TKN) is determined by the calculation. To determine TKN subtract the nitrate-N and nitrite-N in a digested sample from a non-digested sample (see Section 4, Summary of Test Method). 1.3 The limit of detection (LOD), limit of quantitation (LOQ), and reporting range in Table 1 are based on the two-step process for this test method: digestion and analytical step. Because the digestion step requires a sample dilution, the LOD and LOQ are higher than undigested samples. The reporting range, LOD, and LOQ can be modified and perhaps improved depending on several factors (see Section 6, Interferences). (A) Ten calibration levels, each injected in duplicate.(B) LOD calculated as 3 × S/N.(C) LOQ calculated as 10 × S/N.(D) where: A   =   the average method blank concentration,   =   the student’s t-value for the single-tailed 99th percentile t statistic a standard deviation estimate with n – 1 degrees of freedom, and Sb   =   the sample standard deviation of the replicate blank analyses. (E) Phosphate LOD/LOQ was calculated based on a dilution factor of 15× relative to the system concentrations. 1.4 The method detection limits (MDL) are shown for reference. The digestion reagent contains background nitrate and results in higher detection limits. MDL will be shown after the interlaboratory study (ILS) is completed. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 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 The original CIE color scales based on tristimulus values X, Y, Z and chromaticity coordinates x, y are not uniform visually. Each subsequent color scale based on CIE values has had weighting factors applied to provide some degree of uniformity so that color differences in various regions of color space will be more nearly comparable. On the other hand, color differences obtained for the same specimens evaluated in different color-scale systems are not likely to be identical. To avoid confusion, color differences among specimens or the associated tolerances should be compared only when they are obtained for the same color-scale system. There is no simple factor that can be used to convert accurately color differences or color tolerances in one system to difference or tolerance units in another system for all colors of specimens.5.2 Color differences calculated in ΔE00 units (6) are highly recommended for use with color-differences in the range of 0.0 to 5.0 ΔE*ab units. This color-difference equation is appropriate for and widely used in industrial and commercial applications including, but not limited to, automobiles, coatings, cosmetics, inks, packaging, paints, plastics, printing, security, and textiles.5.3 Users of color tolerance equations have found that, in each system, summation of three, vector color-difference components into a single scalar value is very useful for determining whether a specimen color is within a specified tolerance from a standard. However, for control of color in production, it may be necessary to know not only the magnitude of the departure from standard but also the direction of this departure. It is possible to include information on the direction of a small color difference by listing the three instrumentally determined components of the color difference.5.4 Selection of color tolerances based on instrumental values should be carefully correlated with a visual appraisal of the acceptability of differences in hue, lightness, and saturation obtained by using Practice D1729. The three tolerance equations given here have been tested extensively against such data for textiles and plastics and have been shown to agree with the visual evaluations to within the experimental uncertainty of the visual judgments. That implies that the equations themselves misclassify a color difference with a frequency no greater than that of the most experienced visual color matcher.5.5 While color difference equations and color tolerance equations are routinely applied to a wide range of illuminants, they have been derived or optimized, or both, for use under daylight illumination. Good correlation with the visual judgments may not be obtained when the calculations are made with other illuminants. Use of a tolerance equation for other than daylight conditions will require visual confirmation of the level of metamerism in accordance with Practice D4086.1.1 This practice covers the calculation, from instrumentally measured color coordinates based on daylight illumination, of color tolerances and small color differences between opaque specimens such as painted panels, plastic plaques, or textile swatches. Where it is suspected that the specimens may be metameric, that is, possess different spectral curves though visually alike in color, Practice D4086 should be used to verify instrumental results. The tolerances and differences determined by these procedures are expressed in terms of approximately uniform visual color perception in CIE 1976 CIELAB opponent-color space (1),2 CMC tolerance units (2), CIE94 tolerance units (3), the DIN99o color difference formula given in DIN 6176 (4), or the CIEDE2000 color difference units (5).1.2 For product specification, the purchaser and the seller shall agree upon the permissible color tolerance between test specimen and reference and the procedure for calculating the color tolerance. Each material and condition of use may require specific color tolerances because other appearance factors, (for example, specimen proximity, gloss, and texture), may affect the correlation between the magnitude of a measured color difference and its commercial acceptability.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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This specification covers LNG density calculation models for use in the calculation or prediction of the densities of saturated liquefied natural gas (LNG) mixtures at a specified temperature range given the pressure, temperature, and composition of the mixture. Composition restrictions for the LNGs are given for methane, nitrogen, n-butane, i-butane, and pentanes. It is assumed that hydrocarbons with carbon numbers of six or greater are not present in the LNG solution. The mathematical models presented here are the extended corresponding states model, hard sphere model, revised Klosek and McKinley model, and the cell model.1.1 This specification covers Liquefied Natural Gas (LNG) density calculation models for use in the calculation or prediction of the densities of saturated LNG mixtures from 90K to 120K to within 0.1 % of true values given the pressure, temperature, and composition of the mixture.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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5.1 The different procedures and methods are designed to be used to produce survival data after microorganisms are exposed to antimicrobial agents in order to calculate values that can be used to analyze and rationalize the effectiveness of antimicrobial agents when tested using other, often applied test methods.5.2 The data from these test procedures may be used in the selection and design of other tests of effectiveness of antimicrobial agents, some of which may be required by regulatory agencies to establish specific claims. Basic kinetic information about killing rate often serves as the initial information on which a testing program can be built.1.1 This guide covers the methods for determining the death rate kinetics expressed as D-values. These values can be derived from the construction of a kill curve (or survivor curve) or by using other procedures for determining the number of survivors after exposure to antimicrobial chemicals or formulations. Options for calculations will be presented as well as the method for calculation of a concentration coefficient.1.1.1 The test methods are designed to evaluate antimicrobial agents in formulations to define a survivor curve and to subsequently calculate a D-value. The tests are designed to produce data and calculate values that provide basic information of the rate-of-kill of antimicrobial formulations tested against single, selected microorganisms. In addition, calculated D-values from survivor curves from exposure at different dilutions of antimicrobial can be used to show the effect of dilution by calculation of the concentration exponent, η (2). D-value determination assumes the ideal of first-order killing reactions that are reflected in a straight-line reduction in count where a count-versus-time plot is done. The goal here is not to determine the time at which no survivors are found, but to determine a standard value that can be used in processing and exposure determinations or used to estimate dilutions.1.1.2 As an example of potential use of kill curve data, the published FDA, OTC Tentative Final Monograph for Health-Care Antiseptic Drug Products, Proposed Rule, June 17, 1994 has suggested the testing of topically applied antimicrobial products using survival curve (or kill curve) calculations. The methods described in this guide are applicable to these products, but adjustments such as the use of antifoaming agents when the reaction mixture is stirred may be necessary to counteract the presence of detergents in many formulations. Frequently the sampling for these tests is done after very short intervals of exposure to the formulation, such as 30 and 60 s. This methodology also has been applied to preservative testing of antimicrobial ingredients in more complex cosmetic formulations (5).1.2 The test methods discussed should be performed only by those trained in microbiological techniques.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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3.1 This test method is suitable for use in calculating weights and volumes of the products outlined in Section 1. The information presented in this method can be used for determining quantities of the above-stated aromatic hydrocarbons in tanks, shipping containers, etc.1.1 This standard is for use in calculating the weight and volume of benzene, toluene, mixed xylenes, styrene, orthoxylene, meta-xylene, para-xylene, cumene, ethylbenzene, 300 to 350°F and 350 to 400°F aromatic hydrocarbons, and cyclohexane. A method is given for calculating the volume at a desired temperature tb°F from an observed volume at to°F. Table 1 lists the density in Vacuo at 60°F for chemicals used to develop the relationship. Densities (or weights) “in vacuo” represent the true density (or weight) if measured in a vacuum without the buoyancy effect of air acting on the liquid. It is representative of the actual amount of product present. Densities (or weights) “in air” represent what would actually be measured on a scale. The difference is on the order of 0.13 %. Modern densitometers measure density in vacuo and the ASTM recommends the use of in vacuo densities (or weights).1.2 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 A complete SI unit companion standard has been developed in Test Method D1555M.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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3.1 This test method is suitable for use in calculating weights and volumes of the products outlined in Section 1. The information presented in this method can be used for determining quantities of the above-stated aromatic hydrocarbons in tanks, shipping containers, etc.1.1 This standard is for use in calculating the weight and volume of benzene, toluene, mixed xylenes, styrene, ortho-xylene, meta-xylene, para-xylene, cumene, ethylbenzene, 148.9 to 176.7 °C and 176.7 to 204.4 °C aromatic hydrocarbons, and cyclohexane. A method is given for calculating the volume at a given temperature from an observed volume at an observed temperature, t °C. Table 1 lists the density in Vacuo at 15 °F and 20 °C for chemicals used to develop the relationship. Densities (or weights) “in vacuo” represent the true density (or weight) if measured in a vacuum without the buoyancy effect of air acting on the liquid. It is representative of the actual amount of product present. Densities (or weights) “in air” represent what would be measured on a scale. The difference is on the order of 0.13 %. Modern densitometers measure density in vacuo and the ASTM recommends the use of in vacuo densities (or weights).1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 A complete inch-pound unit companion standard has been developed in Test Method D1555.1.3 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 In the design and operation of RO installations, it is important to predict the calcium carbonate scaling properties of the concentrate stream. Because of the increase in total dissolved solids in the concentrate stream and the difference in passages for calcium ion, bicarbonate ion, and free carbon dioxide, the calcium carbonate scaling properties of the concentrate stream will generally be quite different from those of the feed solution. This practice permits the calculation of the Langelier saturation index for the concentrate stream from the feed water analyses and the RO operating parameters.5.2 A positive Langelier saturation index indicates the tendency to form a calcium carbonate scale, which can be damaging to RO performance. This practice gives various procedures for the adjustment of the Langelier saturation index.5.3 The tendency to form calcium carbonate scale can be suppressed by the addition of antiscalents or crystal modifiers. Suppliers of antisealents and crystal modifiers can provide information on the scale inhibition peformance of these types of chemical. Their use may be appropriate for reducing scale formation in RO systems. The RO system supplier should be consulted prior to the use of antisealents and crystal modifiers to ensure they will not have a negative impact on the RO system.1.1 This practice covers the calculation and adjustment of the Langelier saturation index for the concentrate stream of a reverse osmosis (RO) device. This index is used to determine the need for calcium carbonate (CaCo3) scale control in the operation and design of RO installations. This practice is applicable for concentrate streams containing 10 to 10 000 mg/L of total dissolved solids. For concentrate containing over 10 000 mg/L, see Practice D4582.1.2 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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1.1 This practice includes, in Table 1, the commercial composition corresponding to different commercial designations for scoured wool, wool top, and wool noil, all of which contain, in addition to wool base, various percentages of moisture, material extractable with alcohol, and mineral matter.1.2 This practice includes directions for the calculation of the commercial weight of wool corresponding to different commercial designations for several forms of wool, and for converting the commercial weight (mass) calculated on one basis to the commercial weight calculated on a different basis.1.3 This practice also includes directions for calculating the yield, on various commercial designation bases, obtained by processing raw wool, and for converting the yield calculated on one commercial designation basis to the yield on another commercial designation basis.Note 1—Because of trade practice the term “weight” is used in this practice instead of the technically correct term “mass”.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.TABLE 1 Commercial Composition of CommerciallyDesignated Scoured Wool, Wool Top, and Wool Noil PercentageWool Base Moisture Other Compo-nentsASTM Clean Wool Fiber PresentA 86.0000 12.0000 2.0000U.S. Customs Absolute Clean ContentB 86.0000 12.0000 2.0000IWTO Clean Wool ContentC 83.5299 14.5299 1.9402American Oil Combed TopD ,E 82.4222 13.0435 4.5343American Oil Combed NoilD ,E 83.4113 12.0000 4.5887American Dry Combed TopD ,E 84.1454 13.0435 2.8111American Dry Combed NoilD ,E 85.1552 12.0000 2.8448Bradford Oil Combed TopD ,E 79.2980 15.9664 4.7356Bradford Oil Combed NoilD ,E 82.7760 12.2807 4.9433Bradford Dry Combed TopD ,E 82.6449 15.4334 1.9217Bradford Dry Combed NoilD ,E 85.7260 12.2807 1.9933IWTO Noble Oil Combed TopC 79.2995 15.9664 4.7341IWTO Noble Oil Combed NoilC 82.7775 12.2807 4.9418IWTO Noble Dry Combed TopC 82.6469 15.4334 1.9197IWTO Noble Dry Combed NoilC 85.7281 12.2807 1.9912Schlumberger Oil Combed TopC 79.2995 15.9664 4.7341Schlumberger Oil Combed NoilC 81.3503 13.7931 4.8566Schlumberger Dry Combed TopC 82.6469 15.4334 1.9197Schlumberger Dry Combed NoilC 84.2500 13.7931 1.9569A ASTM Method D584, Test for Wool Content of Raw Wool, Laboratory Scale.B Tariff Schedules of the United States of America (1975), Schedule 3, Part 1, Subpart C, Headnote 1(c).C IWTO Core Test Regulations, 1974, International Wool Textile Organization.D Circular No. 3267, Nov. 10, 1954, Boston Wool Trade Assn.E Circular No. 4899, Nov. 2, 1967, Boston Wool Trade Assn.

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