4.1 This test system has advantages in certain respects over the use of static loading systems in the measurement of glass and glass-ceramics:4.1.1 Only minute stresses are applied to the specimen, thus minimizing the possibility of fracture.4.1.2 The period of time during which stress is applied and removed is of the order of hundreds of microseconds, making it feasible to perform measurements at temperatures where delayed elastic and creep effects proceed on a much-shortened time scale, as in the transformation range of glass, for instance.4.2 The test is suitable for detecting whether a material meets specifications, if cognizance is given to one important fact: glass and glass-ceramic materials are sensitive to thermal history. Therefore the thermal history of a test specimen must be known before the moduli can be considered in terms of specified values. Material specifications should include a specific thermal treatment for all test specimens.1.1 This test method covers the determination of the elastic properties of glass and glass-ceramic materials. Specimens of these materials possess specific mechanical resonance frequencies which are defined by the elastic moduli, density, and geometry of the test specimen. Therefore the elastic properties of a material can be computed if the geometry, density, and mechanical resonance frequencies of a suitable test specimen of that material can be measured. Young's modulus is determined using the resonance frequency in the flexural mode of vibration. The shear modulus, or modulus of rigidity, is found using torsional resonance vibrations. Young's modulus and shear modulus are used to compute Poisson's ratio, the factor of lateral contraction.1.2 All glass and glass-ceramic materials that are elastic, homogeneous, and isotropic may be tested by this test method.2 The test method is not satisfactory for specimens that have cracks or voids that represent inhomogeneities in the material; neither is it satisfactory when these materials cannot be prepared in a suitable geometry. Non-glass and glass-ceramic materials should reference Test Method E1875  for non-material specific methodology to determine resonance frequencies and elastic properties by sonic resonance.NOTE 1: Elastic here means that an application of stress within the elastic limit of that material making up the body being stressed will cause an instantaneous and uniform deformation, which will cease upon removal of the stress, with the body returning instantly to its original size and shape without an energy loss. Glass and glass-ceramic materials conform to this definition well enough that this test is meaningful.NOTE 2: Isotropic means that the elastic properties are the same in all directions in the material. Glass is isotropic and glass-ceramics are usually so on a macroscopic scale, because of random distribution and orientation of crystallites.1.3 A cryogenic cabinet and high-temperature furnace are described for measuring the elastic moduli as a function of temperature from –195 to 1200 °C.1.4 Modification of the test for use in quality control is possible. A range of acceptable resonance frequencies is determined for a piece with a particular geometry and density. Any specimen with a frequency response falling outside this frequency range is rejected. The actual modulus of each piece need not be determined as long as the limits of the selected frequency range are known to include the resonance frequency that the piece must possess if its geometry and density are within specified tolerances.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 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 Trace quantities of sulfur compounds in hydrocarbon products can be harmful to many catalytic chemical processes in which these products are used. Maximum permissible levels of total sulfur are normally included in specifications for such hydrocarbons. It is recommended that this test method be used to provide a basis for agreement between two laboratories when the determination of sulfur in hydrocarbon gases is important.4.2 On liquefied petroleum gas, total volatile sulfur is measured on an injected gas sample. For such material a liquid sample must be used to measure total sulfur.1.1 This test method covers determination of sulfur in the range from 1.5 to 100 mg/kg (ppm by mass) by weight in hydrocarbon products that are gaseous at normal room temperature and pressure.NOTE 1: The test method has been tested cooperatively only on high-purity ethylene gas. Precision data have not been developed for other products.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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 It is necessary and useful to test with children because they represent the real end-users for many products. Some products are developed specifically for children, and some are dual-purpose products that are intended for adults and children. Examples include: baby foods, diapers, ready-to-eat cereal, juices, food or lunch kits, candy, toys, vitamins and other pharmaceuticals, music and videos, interactive learning tools, and packaging.4.2 Children have influence over adults' purchase decisions and are responsible for many or some of their own purchase decisions.4.3 Creating a product for children requires input from children because their wants and needs differ from those of adults. For example, they may differ from adults in preferences or sensory acuity, or both, for sweetness, saltiness, carbonation, and texture. It is impossible to predict the nature of these differences without actual input from the intended target audience.1.1 This guide provides a framework for understanding the issues relating to conducting sensory and market research studies with children. It recommends and provides examples for developing ethical, safe, and valid testing methods. It focuses specifically on the concerns relevant to testing with children from birth through preadolescence. The guide assumes that minors older than 15 years of age are generally capable of performing sensory tests like adults, and therefore, all standard procedures used with adult subjects apply. The one exception, however, is legal consent where parental/legal guardian permission should be obtained for anyone under 18 years of age.1.2 This guide will take into account the wide range of children's physical, emotional, and cognitive levels of development. It will prove useful for developing tasks that are understandable to children. It recommends alternative modes for children to communicate their opinions or perceptions back to the researcher, such as appropriate scales and measures.1.3 The ethical standard presented in this document should be viewed as a minimum requirement for testing with minors. The safety and protection of children as respondents, as well as an attitude of respect for the value of their input should be of primary concern to the researcher.1.4 The considerations raised in this document may also be useful when testing with the elderly or with adults who have developmental handicaps.1.5 This document is not intended to be a complete description of reliable sensory testing techniques and methodologies. It focuses instead on special considerations for the specific application of sensory techniques when testing with children. It assumes knowledge of basic sensory and statistical analysis techniques.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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This test method details the standard procedure for measuring the viscosity of resin solutions. The apparatuses required here are constant-temperature water bath, wide-mouthed screw capped bottles, cellophane sheets, No. 2 short taper corks, viscosity tube holder, bottle shaker, timing device, and viscosity tubes. Solid resins are dissolved in organic solvents by cold-cut or hot-cut methods in the laboratory. The viscosity of such prepared solutions, or of commercial solutions of resins is then determined by the bubble time method. The bubble seconds are approximately equal to stokes.1.1 This practice provides instructions for preparing resin solutions viscosity measurement by bubble time method.1.2 The values stated in SI units are to be regarded as the standard. The values given 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. For specific hazard statements, see Section 7.1.4 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 Assumptions: 5.1.1 The control well discharges at a constant rate, Q.5.1.2 The control well is of infinitesimal diameter and fully penetrates the aquifer.5.1.3 The aquifer is homogeneous, isotropic, and areally extensive.NOTE 1: Slug and pumping tests implicitly assume a porous medium. Fractured rock and carbonate settings may not provide meaningful data and information.5.1.4 The aquifer remains saturated (that is, water level does not decline below the top of the aquifer).5.1.5 The aquifer is overlain or underlain, or both, everywhere by confining beds individually having uniform hydraulic conductivities, specific storages, and thicknesses. The confining beds are bounded on the distal sides by one of the cases shown in Fig. 1.5.1.6 Flow in the aquifer is two-dimensional and radial in the horizontal plane.5.2 The geometry of the well and aquifer system is shown in Fig. 1.5.3 Implications of Assumptions: 5.3.1 Paragraph 5.1.1 indicates that the discharge from the control well is at a constant rate. Paragraph 8.1 of Test Method D4050 discusses the variation from a strictly constant rate that is acceptable. A continuous trend in the change of the discharge rate could result in misinterpretation of the water-level change data unless taken into consideration.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 are generally 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.5.3.2 The leaky confining bed problem considered by the modified Hantush method requires that the control well has an infinitesimal diameter and has no storage. Moench (6) generalized the field situation addressed by the modified Hantush (1) method to include the well bore storage in the pumped well. The mathematical approach that he used to obtain a solution for that more general problem results in a Laplace transform solution whose analytical inversion has not been developed and probably would be very complicated, if possible, to evaluate. Moench (6) used a numerical Laplace inversion algorithm to develop type curves for selected situations. The situations considered by Moench indicate that large well bore storage may mask effects of leakage derived from storage changes in the confining beds. The particular combinations of aquifer and confining bed properties and well radius that result in such masking is not explicitly given. However, Moench ((6), p. 1125) states “Thus observable effects of well bore storage are maximized, for a given well diameter, when aquifer transmissivity Kb and the storage coefficient Ssb are small.” Moench (p. 1129) notes that “...one way to reduce or effectively eliminate the masking effect of well bore storage is to isolate the aquifer of interest with hydraulic packers and repeat the pump test under pressurized conditions. Because well bore storage C will then be due to fluid compressibility rather than changing water levels in the well”...“the dimensionless well bore storage parameter may be reduced by 4 to 5 orders of magnitude.”5.3.3 The modified Hantush method assumes, for Cases 1 and 3 (see Fig. 1), that the heads in source layers on the distal side of confining beds remain constant. Neuman and Witherspoon (7) developed a solution for a case that could correspond to Hantush's Case 1 with K" = O  = S" except that they do not require the head in the unpumped aquifer to remain constant. For that case, they concluded that the drawdowns in the pumped aquifer would not be affected by the properties of the other, unpumped, aquifer when (Neuman and Witherspoon (7) p. 810) time satisfies:5.3.4 Implicit in the assumptions are the conditions that the flow in the confining beds is essentially vertical and in the aquifer is essentially horizontal. Hantush's (8) analysis of an aquifer bounded only by one leaky confining bed suggested that these assumptions are acceptably accurate whereverThat form of relation between aquifer and confining bed properties may also be a useful guide for the case of two leaky confining beds.1.1 This practice covers an analytical procedure for determining the transmissivity and storage coefficient of a confined aquifer taking into consideration the change in storage of water in overlying or underlying confining beds, or both. This practice is used to analyze water-level or head data collected from one or more observation wells or piezometers during the pumping of water from a control well at a constant rate. With appropriate changes in sign, this practice also can be used to analyze the effects of injecting water into a control well at a constant rate.1.2 This analytical procedure is used in conjunction with Test Method D4050.1.3 Limitations—The valid use of the modified Hantush method (1)2 is limited to the determination of hydraulic properties for aquifers in hydrogeologic settings with reasonable correspondence to the assumptions of the Hantush-Jacob method (Practice D6029/D6029M) with the exception that in this case the gain or loss of water in storage in the confining beds is taken into consideration (see 5.1). All possible combinations of impermeable beds and source beds (for example, beds in which the head remains uniform) are considered on the distal side of the leaky beds that confine the aquifer of interest (see Fig. 1).FIG. 1 Cross Sections Through Discharging Wells in Leaky Aquifers with Storage of Water in the Confining Beds, Illustrating Three Different Cases of Boundary Conditions (from Reed (2) )1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 The procedures used to specify how data are collected/recorded and calculated in the 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 these test methods to consider significant digits used in analysis methods for engineering data.1.5 The values stated in SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values for the two systems may result in nonconformance with the standard. Reporting of results in units other than SI shall not be regarded as nonconformance with this standard.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.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.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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5.1 The significance of this test is to determine the thermoplastic pavement marking material’s resistance to impact over a simulated pavement substrate, under laboratory conditions, and is expressed as pass/fail or numerically. The test result can be used as a quality test or to differentiate marking materials.5.2 Anyone attempting to perform this test should initially review Test Methods D5420 and D2794, specifically the equipment setup.5.3 Sample preparation and equipment set-up should be followed precisely to minimize variability in the test result.1.1 This test method covers the sample preparation over a road-type substrate and test methodology of thermoplastic pavement marking materials similar to the “Gardner Impact” method as listed in Test Method D5420.1.2 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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The prime purpose of this test method is to provide data expressed as either electrophoretic mobility or zeta potential distribution of protein particles.Both sellers and purchasers of protein particles will find this test method useful to determine either mobility or zeta potential distributions for protein specifications, manufacturing control, and development and research.1.1 This test method describes a procedure for determining the electrophoretic mobility of proteins of molecular weight greater than 10 000 Daltons.1.2 This test method uses automatic Electrophoretic Light Scattering (ELS) principles to determine the electrophoretic mobility.1.3 The instrument simultaneously measures the Doppler shifts of scattered light at four different angles to determine the electrophoretic mobility distribution of protein particles. The mobility is expressed as m-cm/V-s (micron-centimeter/volt-second).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 Silver may be used to treat consumer textile products to provide enhanced antimicrobial (fungi, bacteria, viruses) properties (3, 4). At any point in a textile product’s lifecycle, there may be a need to measure the amount of silver present. This standard prescribes a test method based on ICP-OES or ICP-MS analysis that manufacturers, producers, analysts, policymakers, regulators, and others may use for measurement of total silver in textiles. As described in Guide E3025, determination of total silver in a consumer textile product is one component of a tiered approach to determine if silver is present, possibly as nanomaterial(s) (one or more external dimensions in the nanoscale), prior to measuring the form and dimension of the Ag that is found. ICP-OES or ICP-MS analysis alone is not sufficient to determine whether a textile contains silver nanomaterial(s).NOTE 4: There are many different chemical and physical forms of silver that are used to treat textiles and an overview of this topic is provided in Guide E3025.5.2 As described in Guide E3025, the amount of silver in a textile can decrease over time as silver metal and silver compounds can react with oxygen and other oxidation-reduction (redox) active agents present in the environment to form soluble ionic species which are released by contact with moisture (for example, from ambient humidity, washing, body sweat, rain, or other sources). Hence, if silver is measured in a textile, the result may only be indicative of that moment in the article’s life cycle and great care is necessary in drawing temporal inferences from the results.5.3 If silver is measured by ICP-OES or ICP-MS analysis, additional analyses are needed to elucidate the form of silver in the textile specimen. This step is necessary because ICP-OES or ICP-MS results are for total silver independent of chemical and physical form and textiles may be treated with silver in sizes that range from the nanoscale (for example, salt nanoparticles) to the micrometer scale (for example, particulates or fibers).5.4 If no silver is detected by ICP-OES, the more sensitive ICP-MS should be used to determine if silver is present in a test specimen. If no silver is detected in a textile sample using appropriate (fit for purpose) analytical techniques, then testing can be terminated.NOTE 5: Typical method detection limits are 0.6 µg Ag/L by ICP-OES and 0.002 µg Ag/L by ICP-MS which are comparable to limits successfully used to detect silver in a range of products, including sports textiles and wound dressings (2).5.5 Results of ICP-OES or ICP-MS analysis may be qualitative or quantitative, depending upon the efficacy of the digestion procedure for the textile matrix. Regardless, ICP-OES or ICP-MS analysis is recommended as a first step to screen for the presence of silver in a textile and results can be used to inform subsequent more detailed analyses as part of a tiered approach to determine if a textile contains silver nanomaterial(s).1.1 This test method covers the use of inductively coupled plasma–optical emission spectrometry (ICP-OES) and inductively coupled plasma–mass spectrometry (ICP-MS) analyses for determination of the mass fraction of total silver in consumer textile products made of any combination of natural or manufactured fibers. Either ICP-OES or ICP-MS analysis is recommended as a first step to test for and quantify silver in a textile and results can be used to inform subsequent, more detailed analyses as part of the tiered approach described in Guide E3025 to determine if a textile contains silver nanomaterial(s).1.2 This test method prescribes acid digestion to prepare test sample solutions from samples of textiles utilizing an appropriate internal standard followed by external calibration and analysis with either ICP-OES or ICP-MS to quantify total silver.1.3 This test method is believed to provide quantitative results for textiles made of fibers of rayon, cotton, polyester, and lycra that contain metallic silver (see Section 17). It is the analyst’s responsibility to establish the efficacy (ability to achieve the planned and desired analytical result) of this test method for other textile matrices and forms of silver.1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurements 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.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 This test method allows the determination of the chemical composition of powdered and sintered tungsten-based hardmetals. This test method is not applicable to material which will not oxidize readily at high temperatures in air, such as tungsten/copper, tungsten/silver alloys, or tungsten/cobalt-ruthenium alloys.5.2 This test method specified lithium-borate compounds for the glass fusion material. However, numerous other choices are available. These include other lithium-borate compounds, sodium carbonate and borate mixtures, and others. The methodology specified here is still applicable as long as the same fusion mixture is used for both standards and specimens.1.1 This test method describes a procedure for the determination of the concentration, generally reported as mass percent, of the metallic constituents of tungsten-based alloys and hardmetals utilizing wavelength dispersive X-ray fluorescence spectrometry (XRF). This test method incorporates the preparation of standards using reagent grade metallic oxides, lithium-borate compounds, and fusion techniques. This test method details techniques for preparing representative specimens of both powder and sintered tungsten-based material. This test method is accurate for a wide range of compositions, and can be used for acceptance of material to grade specifications.1.2 This test method is applicable to mixtures of tungsten or tungsten carbide with additions of refractory metal carbides and binder metals. Table 1 lists the most common elemental constituents and their concentration range. Note that many of these occur as metallic carbides.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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4.1 Shipping containers and the interior packaging materials are used to protect their contents from the hazards encountered in handling, transportation, and storage. Shock is one of the more troublesome of these hazards. Free-fall drop testing, while easy to perform, often understresses the test specimen by subjecting it to drops which are not perpendicular to the dropping surface. Note 1: For example, testing has shown that non-perpendicular drops, 2° off perpendicularity, result in 8 % lower acceleration into the test specimen resulting from the impact energy dispersing in several axes.4 4.1.1 Controlled shock input by shock machines provides a convenient method for evaluating the ability of shipping containers, interior packaging materials, and contents to withstand shocks. Simulated free-fall drop testing of package systems, which have critical elements, has produced good results where the frequency of the shock pulse is at least three times that of the package system's natural frequency. 4.2 As in most mechanical shock test procedures, fixturing of the package on the shock test machine may have significant influence on the test results. Typically, packages will be firmly held on the table by securing some type of cross member(s) across the top of the package. Care should be taken that any pressure resulting from such fixturing should be minimal, particularly when the container being tested is corrugated or some other similar material. 4.2.1 In cases where low-acceleration, long-duration responses are anticipated, any fixturing can potentially influence packaged item response and can possibly alter any correlation between this test method and free-fall drop testing. Where such correlation is desired, the package can be tested without it being fixed directly to the table. Note that in such circumstances, the shipping container can vigorously rebound from the table and can, if not otherwise controlled, present a safety problem for operators. Fixing the shipping container to the shock machine table is most often recommended for safety and convenience, but accuracy and precision of this test method should not be compromised by such fixturing. Note 2: A rigid package system with a natural frequency above 83 Hz requires a shock pulse shorter than the 2-ms (nominal) duration currently available with many of today's shock machines: where: ds   =   shock pulse duration, s, fs   =   shock pulse frequency, Hz, and fp   =   package system frequency, which may be determined by Test Methods D999. Similarly, a shock machine using an input shock pulse duration of 3 ms would only be effective with package system frequencies below 56 Hz. 1.1 This test method covers the general procedures of using shock machines to replicate the effects of vertical drops of loaded shipping containers, cylindrical containers, and bags and sacks. 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 Nonylphenol,4 octylphenol, and bisphenol A have been shown to have toxic effects in aquatic organisms. The source of nonylphenol and octylphenol is prominently from the use of common commercial surfactants. The most widely used surfactant is NPEO which has an average ethoxylate chain of 9 mol of ethoxylate. The ethoxylate chain is readily biodegraded to form NP1EO and NP2EO, nonylphenol carboxylate (NPEC) and, under anaerobic conditions, nonylphenol. Nonylphenol will also biodegrade, but may be released into environmental waters directly at trace levels. This test method has been investigated for use with surface water and waste treatment effluent samples and is applicable to these matrices. It has not been investigated for use with salt water or solid sample matrices.5.2 The first reported synthesis of BPA was by the reaction of phenol with acetone by Zincke.5 BPA has become an important high volume industrial chemical used in the manufacture of polycarbonate plastics and epoxy resins. Polycarbonate plastic and resins are used in numerous products including electrical and electronic equipment, automobiles, sports and safety equipment, reusable food and drink containers, electrical laminates for printed circuit boards, composites, paints, adhesives, dental sealants, protective coatings, and many other products.6 The environmental source of BPA is predominantly from the decomposition of polycarbonate plastics and resins. BPA is not classified as bio-accumulative by the U.S. Environmental Protection Agency (EPA) and will biodegrade. BPA may be released into the environment waters directly at trace levels through landfill leachate and sewage treatment plant effluents.1.1 This test method covers determination of nonylphenol (NP), nonylphenol ethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO), octylphenol (OP), and bisphenol A (BPA) that are partitioned into organic solvent, separated using gas chromatography and detected with mass selective detection. These compounds or isomer mixtures are qualitatively and quantitatively determined by this test method. This test method adheres to selected ion monitoring mass spectrometry but full scan mass spectrometry has also been shown to work well under these conditions. Either analysis may be used.1.2 The method detection limit (MDL) and reporting limit (RL) for NP, NP1EO, NP2EO, OP, and BPA are listed in Table 1.(A) MDL determined following the Code of Federal Regulations, 40 CFR Part 136, Appendix B.(B) Lowest point of the reporting range is calculated from the LV1 concentration calibration standard in Table 4.1.3 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 This test method is intended for use in the laboratory or in the field for evaluating the cleanliness of distillate fuels, and liquid bio fuels. It is not applicable to on or in-line applications.5.2 This test method offers advantage over traditional filtration methods in that it is a precise rapid test, and advantage over visual methods as it is not subjective.5.3 An increase in particle counts can indicate a change in the fuel condition caused by storage or transfer for example.5.4 High levels of particles can cause filter blockages and have a serious impact on the life of pumps, injectors, pistons and other moving parts. Knowledge of particle size in relation to the metallurgy can provide vital information especially if the hardness of particles is also known from other sources.5.5 This test method specifies a minimum requirement for reporting measurements in particle size bands (see A1.1.2). Some specific applications may require measurements in other particle size bands.5.6 Obtaining a representative sample and following the recommended sample and test specimen preparation procedures and timescales is particularly important with particle counting methods. (See Sections 8, 10, 14.1.4 and Note 8.)5.7 This test method can also be used to estimate the total particulate counts excluding free water droplets in aviation turbine fuels by a chemical pretreatment of the fuel. See Appendix X2.1.1 This test method uses a specific automatic particle counter2 (APC) to count and measure the size of dispersed dirt particles, water droplets and other particles, in light and middle distillate fuel, and bio fuels such as biodiesel and biodiesel blends, in the overall range from 4 µm(c) to 100 µm(c) and in the size bands ≥4 µm(c), ≥6 µm(c), and ≥14 µm(c).NOTE 1: ASTM and military specification fuels falling within the scope of this test method include Specifications: D975 grades 1D and 2D, D1655, D3699, D4814 (see 14.1.1.1), D6751, D7467, distillate grades of D396 and D2880, MIL-DTL-83133, and MIL-DTL-16884.NOTE 2: For the purposes of this test method, water droplets are counted as particles, and agglomerated particles are detected and counted as a single larger particle. Dirt includes biological particles. Although the projected area of a particle is measured, this is expressed as the diameter of a sphere for the purposes of this test method.NOTE 3: The notation (c), used with particle sizes, is used to denote that the apparatus has been calibrated in accordance with ISO 11171. Strictly this only applies to particles up to 50 µm.NOTE 4: This test method may be used for particle sizes bands up to 100 µm(c), however the precision has only been determined for the size bands ≥4 µm(c), ≥6 µm(c), and ≥14 µm(c). All measurements are per millilitre.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 This test method provides a means to evaluate the resistance to particle shedding of a thermal spray coating. Such particle shedding might occur during surgical insertion of an implant or as the result of micromotion of the implant after insertion.5.2 This abrasion test method may be useful for quality control analysis of a coating, and it can be used to evaluate the effects of processing variables, such as substrate preparation before coating, surface texture, coating technique variables, or postcoating treatments, any of which may influence the susceptibility of the coating to particle shedding.5.3 This abrasion test method is for flat plate-shaped specimens of a size sufficient that the wheels of the abrader do not leave the surface of the specimen. It is not recommended for devices with other shapes or sizes.1.1 This test method quantifies the abrasion resistance of metallic coatings produced by thermal spray processes on flat metallic surfaces. It is intended as a means of characterizing coatings used on surgical implants.1.2 This test uses the Taber Abraser,2 which generates a combination of rolling and rubbing to cause wear to the coating surface. Wear is quantified as cumulative weight loss.1.3 This test method is limited to flat, rigid specimens that do not react significantly with water and do not undergo a phase transformation or chemical reaction between room temperature and 100 °C in air.1.4 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.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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4.1 The composition and sequential structure of alginate determines the functionality of alginate in an application. For instance, the gelling properties of an alginate are highly dependent upon the monomer composition and sequential structure of the polymer. Gel strength will depend upon the guluronic acid content (FG) and also the average number of consecutive guluronate moieties in G-block structures (NG>1).4.2 Chemical composition and sequential structure of alginate can be determined by 1H- and 13C-nuclear magnetic resonance spectroscopy (NMR). A general description of NMR can be found in <761> of the USP 35-NF30. The NMR methodology and assignments are based on data published by Grasdalen et al. (1979, 1981, 1983).4, 5, 6 The NMR technique has made it possible to determine the monad frequencies FM (fraction of mannuronate units) and FG (fraction of guluronate units), the four nearest neighboring (diad) frequencies FGG, FMG, FGM, FMM, and the eight next nearest neighboring (triad) frequencies FGGG, FGGM, FMGG, FMGM, FMMM, FMMG, FGMM, FGMG. Knowledge of these frequencies enables number averages of block lengths to be calculated. NG is the number average length of G-blocks, and NG>1 is the number average length of G-blocks from which singlets (-MGM-) have been excluded. Similarly, NM is the number average length of M-blocks, and NM>1 is the number average length of M-blocks from which singlets (-GMG-) have been excluded. 13C NMR must be used to determine the M-centered triads and NM>1. This test method describes only the 1H NMR analysis of alginate. Alginate can be well characterized by determining FG and NG>1.4.3 In order to obtain well-resolved NMR spectra, it is necessary to reduce the viscosity and increase the mobility of the molecules by depolymerization of alginate to a degree of polymerization of about 20 to 50. Acid hydrolysis is used to depolymerize the alginate samples. Freeze-drying, followed by dissolution in 99 % D2O, and another freeze-drying before dissolution in 99.9 % D2O yields samples with low 1H2O content. TTHA is used as a chelator to prevent traces of divalent cations to interact with alginate. While TTHA is a more effective chelator, other agents such as EDTA and citrate may be used. Such interactions may lead to line broadening and selective loss of signal intensity.4.4 Samples are analyzed at a temperature of 80 ± 1°C. Elevated sample temperature contributes to reducing sample viscosity and repositions the proton signal of residual water to an area outside that of interest.1.1 This test method covers the determination of the composition and monomer sequence of alginate intended for use in biomedical and pharmaceutical applications as well as in Tissue Engineered Medical Products (TEMPs) by high-resolution proton NMR (1H NMR). A guide for the characterization of alginate has been published as Guide F2064.1.2 Alginate, a linear polymer composed of β-D-mannuronate (M) and its C-5 epimer α-L-guluronate (G) linked by β-(1—>4) glycosidic bonds, is characterized by calculating parameters such as mannuronate/guluronate (M/G) ratio, guluronic acid content (G-content), and average length of blocks of consecutive G monomers (that is, NG>1 ). Knowledge of these parameters is important for an understanding of the functionality of alginate in TEMP formulations and applications. This test method will assist end users in choosing the correct alginate for their particular application. Alginate may have utility as a scaffold or matrix material for TEMPs, in cell and tissue encapsulation applications, and in drug delivery formulations.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 In-vitro cell proliferation assays are used to screen the capability of cells to proliferate and self-renew within scaffolds for regenerative medicine and tissue-engineering applications. The cell proliferation in vitro, in conjunction with other characteristics of the cells such as gene expression, can be used to determine if the cells have maintained their properties.5.2 Cell proliferation may be an important parameter to test as a quality attribute of a cell-scaffold construct. This test helps to assess cell colonization within a scaffold.5.3 This method provides a technique for vital assessment and quantification of the fluorescence intensity related to dye metabolism by living and proliferating cells. This method assumes that viable cells will have an active metabolism, which is required to support life-associated cellular processes such as the conversion of nutrient sources into energy and proliferation. There may be cells that are not actively proliferating, yet are still viable within the construct. The methods described within this practice enable nondestructive testing for monitoring the cell proliferation kinetics throughout the culture period by repeated analysis at multiple time points on the same test sample with minimal toxicity. This standard practice is written only for resazurin dye, a non-cytotoxic reagent that should not affect cell viability and proliferation at low concentration. This is a distinct advantage over many other reagents used to measure cell number, such as measurements of the intracellular components (such as DNA, protease, or ATP) which require cell lysis and can therefore only be used for endpoint analysis.5.4 Resazurin, which has low fluorescence, may be metabolized by cells into resorufin, which is highly fluorescent. An increase in fluorescence caused by the conversion to resorufin may correlate with increased dehydrogenase activity, which may correlate with an increase in cell number and therefore proliferation. Plotting the signals measured at multiple time points enables the generation of proliferation curves. It is important to note that metabolic assays are intended to be measurements of intracellular dehydrogenase or reductase enzyme activity produced by cells. The level of enzyme activity may be directly proportional to the number of viable cells within a range of cell number per volume (or per scaffold) identified by a calibration curve. This is because cell metabolism rate may decrease without a loss in cell viability when cells have reached confluency or when they are differentiating. Some cells may be quiescent but still viable. Furthermore, certain cell types have different metabolic activity. In these situations, the relationship between cell metabolism and cell number may not be linear and other assays may be considered.5.5 The method may be applied to planar 2D cell cultures and 3D scaffold cell cultures. This assay is intended for 96, 48, and 24-well plates but could work for other size plates. Size and thickness of cell scaffold construct where the test can be applicable should be tested with control experiments. In Reference (4), a 5 mm thick scaffold in a 24-well plate was used.5.6 The method may also be used to document the absence of cell proliferation in cultures.NOTE 1: The absence or suppression of proliferation under the tested conditions may be a result of lack of reagent/nutrient diffusion through the scaffold. If so, the same result may not be observed if diffusion is improved by, for example, changing from a 96-well plate to other cell culture formats.5.7 The dye is not cell type specific; hence, cell identification cannot be based on this method.5.8 The assay as described herein is not designed to assess cell distribution in scaffolds. It is possible that this could be achieved by sectioning the scaffolds prior to staining and analysis.1.1 This practice describes how to conduct a nondestructive proliferation test for mammalian cells based on metabolic activity that can be used to assess the number of viable cells within three-dimensional (3D) scaffolds for regenerative medicine and in tissue-engineered medical products (TEMPs).1.2 This practice provides a detailed explanation of the resazurin cell metabolic activity method in terms of reagent concentrations, incubation times, cell culture media composition, calibration curve, controls, assay linearity, and limitations of the assay.1.3 This practice describes factors that can interfere with accurate cell proliferation assessment.1.4 Since the assay has washing steps, it is limited to assessing cells that are immobilized, such as by adhesion to a culture dish, adhesion to a scaffold, or encapsulation in a hydrogel.1.5 The assay is limited to cell types that can metabolize resazurin to provide a signal in the assay.1.6 This document does not propose acceptance criteria for a cell-based product based on the application of a cell proliferation test method.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.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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