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5.1 This wipe sampling and indirect analysis test method is used for the general testing of surfaces for asbestos. It is used to assist in the evaluation of surfaces in buildings, such as ceiling tiles, shelving, electrical components, duct work, and so forth. This test method provides an index of the concentration of asbestos structures per unit area sampled as derived from a quantitative measure of the number of asbestos structures detected during analysis.5.1.1 This test method does not describe procedures or techniques required for the evaluation of the safety or habitability of buildings with asbestos-containing materials, or compliance with federal, state, or local regulations or statutes. It is the user's responsibility to make these determinations.5.1.2 At present, a single direct relationship between asbestos sampled from a surface and potential human exposure does not exist. Accordingly, the user should consider these data in relationship to other available information (for example, air sampling data) in their evaluation.5.2 One or more large asbestos-containing particles dispersed during sample preparation may result in large asbestos surface loading results in the TEM analyses of that sample. It is, therefore, recommended that multiple replicate independent samples be secured in the same area, and that a minimum of three such samples be analyzed by the entire procedure.1.1 This test method covers a procedure to identify asbestos in samples wiped from surfaces and to provide an estimate of the concentration of asbestos reported as the number of asbestos structures per unit area of sampled surface. The procedure outlined in this test method employs an indirect sample preparation technique. It is intended to disperse aggregated asbestos into fundamental fibrils, fiber bundles, clusters, or matrices. However, as with all indirect sample preparation techniques, the asbestos observed for quantification may not represent the physical form of the asbestos as sampled. More specifically, the procedure described neither creates nor destroys asbestos, but it may alter the physical form of the mineral fiber aggregates.1.2 This test method describes the equipment and procedures necessary for wipe sampling of surfaces for levels of asbestos structures. The sample is collected onto a particle-free wipe material (wipe) from the surface of a sampling area that may contain asbestos.1.2.1 The collection efficiency of this wipe sampling technique is unknown and will vary among substrates. Properties influencing collection efficiency include surface texture, adhesiveness, and other factors.1.2.2 This test method is generally applicable for an estimate of the surface loading of asbestos structures starting from approximately 1000 asbestos structures per square centimetre.1.3 Asbestos identification by transmission electron microscopy (TEM) is based on morphology, electron diffraction (ED), and energy dispersive X-ray analysis (EDXA).1.4 This test method allows determination of the type(s) of asbestos fibers present.1.4.1 This test method cannot always discriminate between individual fibers of the asbestos and nonasbestos analogues of the same amphibole mineral.1.4.2 There is no lower limit to the dimensions of asbestos fibers that can be detected. However, in practice, the lower limit to the dimensions of asbestos fibers, that can be detected, is variable and dependent on individual microscopists. Therefore, a minimum length of 0.5 μm has been defined as the shortest fiber to be incorporated in the reported results.1.5 The values stated in SI units are to be regarded as 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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5.1 As AFM measurement technology has matured and proliferated, the technique has been widely adopted by the nanotechnology research and development community to the extent that it is now considered an indispensible tool for visualizing and quantifying structures on the nanoscale. Whether used as a stand-alone method or to complement other dimensional measurement methods, AFM is now a firmly established component of the nanoparticle measurement tool box. International standards for AFM-based determination of nanoparticle size are nonexistent as of the drafting of this guide. Therefore, this standard aims to provide practical and metrological guidance for the application of AFM to measure the size of substrate-supported nanoparticles based on maximum displacement as the probe is rastered across the particle surface to create a line profile.1.1 The purpose of this document is to provide guidance on the quantitative application of atomic force microscopy (AFM) to determine the size of nanoparticles2 deposited in dry form on flat substrates using height (z-displacement) measurement. Unlike electron microscopy, which provides a two-dimensional projection or a two-dimensional image of a sample, AFM provides a three-dimensional surface profile. While the lateral dimensions are influenced by the shape of the probe, displacement measurements can provide the height of nanoparticles with a high degree of accuracy and precision. If the particles are assumed to be spherical, the height measurement corresponds to the diameter of the particle. In this guide, procedures are described for dispersing gold nanoparticles on various surfaces such that they are suitable for imaging and height measurement via intermittent contact mode AFM. Generic procedures for AFM calibration and operation to make such measurements are then discussed. Finally, procedures for data analysis and reporting are addressed. The nanoparticles used to exemplify these procedures are National Institute of Standards and Technology (NIST) reference materials containing citrate-stabilized negatively charged gold nanoparticles in an aqueous solution.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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Carbon black morphology significantly affects the transient and end-use properties of carbon black loaded polymer systems. A carbon black’s particle size distribution is its single most important property, and it relates to degree of blackness, rubber reinforcement, and ability to impart UV protection. For a given loading of carbon black, blackness, reinforcement, and UV protection increase with smaller particle size. Aggregate size and shape (structure) also affect a carbon black's end-use performance, as higher carbon black structure increases viscosity and improves dispersion. The stiffness (modulus) of elastomer systems becomes significantly higher with increasing structure. The preferred method for measuring carbon black morphology (for example, size and shape) is transmission electron microscopy (TEM), but due to the semi-quantitative nature of TEM, it is not suited for mean particle size (MPS) certification. While useful morphological information can be obtained from TEM measurements within a laboratory, due to their inherent between-laboratory variability, TEM generated values should not be used for specification purposes.4.2 Certification of carbon blacks for UV protection (weatherability) in certain plastics applications has historically been performed using TEM generated mean particle size values. ASTM Committee D24 has demonstrated that due to challenges with obtaining quantitative primary particle size data, particularly between laboratories, a qualification test based on surface area has been implemented, as detailed in Test Method B.4.3 Carbon black aggregate dimensional and shape properties are dependent upon the nature of the system in which the sample is dispersed, as well as the mixing procedure.1.1 This test method covers (1) the morphological (for example, size and shape) characterization of carbon black from transmission electron microscope images which are used to derive the mean particle and aggregate size of carbon black in the dry (as manufactured) state, from CAB chip dispersion or removed from a rubber compound and (2) the certification of mean particle size using a correlation based on statistical thickness surface area measurements.1.2 The values stated in SI units are to be regarded as the standard. 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.

定价： 590元 / 折扣价： 502 元 加购物车

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5.1 Chemical composition of water-formed deposits is a major indicator of proper or improper chemical treatment of process water, and is often an indicator of operational parameters as well, for example, temperature control. This practice allows for rapid determination of constituents present in these deposits, particularly those indications of improper water treatment, since they usually have very distinctive and easily recognized optical properties.5.2 This practice, where applicable, eliminates the need for detailed chemical analysis, which is time-consuming, and which does not always reveal how cations and anions are mutually bound.5.3 Qualitative use of this practice should be limited to those deposits whose control is generally known or predictable, based on treatment and feedwater mineral content, and whose constituents are crystalline, or in other ways optically or morphologically distinctive. If these criteria are not met, other techniques of analysis should be used, such as Practice D2332 or Test Methods D3483, or both.5.4 Quantitative use of this practice should be limited to estimates only. For more precise quantitative results, other methods should be used (see 5.3).1.1 This practice describes a procedure for the examination of water-formed deposits by means of chemical microscopy. This practice may be used to complement other methods of examination of water-formed deposits as recommended in Practices D2331 or it may be used alone when no other instrumentation is available or when the sample size is very small.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.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 Cryo-TEM is a technique used to record high resolution images of samples that are frozen and embedded in a thin layer of vitrified, amorphous ice (2-5). Because vitrification occurs so rapidly, the resultant specimen is almost instantly frozen, yielding a very accurate representation of the specimen at the moment of freezing, without the distortions typically associated with air drying delicate wet samples. Once frozen, images of the specimen are recorded at low temperature using a specially designed electron microscope equipped with a cryo-holder capable of operating under low dose conditions in order to prevent beam induced structural damage to the specimen. The cryo-TEM technique is the consensus choice to directly observe, analyze and accurately measure liposomes suspended in aqueous solutions. Fig. 1 illustrates this by comparing an electron micrograph from an air-dried negatively stained liposomal preparation with an electron micrograph of the same solution imaged by cryo-TEM.FIG. 1 Left—An Electron Micrograph of an Air-Dried Liposomal Preparation that has been Negatively Stained with 2 % Uranyl Acetate for Contrast; Right—An Electron Micrograph of the Same Liposomal Preparation Prepared as a Frozen Vitrified Specimen for Cryo-TEMNOTE 1: Both images are shown to the same scale; scale bar is 200 nm.5.1.1 Fig. 1 demonstrates that liposomes may become distorted and are difficult to measure and analyze when they are air-dried, while the same liposomal preparation is clearly easier to analyze when the specimen is near-instantly preserved by vitrification.5.1.2 Cryo-TEM involves applying a small volume of sample to a specially prepared holey, ultra-thin or continuous carbon grid suspended in a cryo-TEM plunger over a cup of liquid ethane cooled in a container filled with liquid nitrogen (2, 3). These grids can be purchased or prepared in the laboratory using a carbon evaporator with glow discharge capabilities. Once the sample has wet the surface of the grid, and sufficient time allowed for the solution to equilibrate with regard to liposome spreading over the grid surface, the excess is wicked off (blotted) with filter paper and the grid plunged into the liquid ethane, vitrifying the sample. Once frozen, the sample is maintained at a liquid nitrogen temperature while it is imaged in a cryo-TEM operating under low electron dose conditions. There are several limitations associated with implementing this technique to analyze liposomes:5.1.2.1 Thick Ice—The vitrified ice thickness is often determined by the sample or the cryo-TEM procedure itself. Large liposomes, defined to include larger structure and sizes with respect to this practice, are generally associated with thicker ice, while smaller liposomes (structure and sizes) are associated with thinner ice. Generally, thick ice occurs when either excess water forms a thicker ice layer or samples containing larger liposomes are fully covered with water making the ice thicker around the sample. Thicker ice tends to block the electron beam either completely or partially which compromises image quality.5.1.2.2 Larger liposomes (structure and sizes) are preferentially lost during sample preparation.Larger liposomes, defined to include larger structures and sizes with respect to this practice, are more difficult to image for two reasons. The first is the cryo-TEM procedure itself. This procedure requires the use of filter paper to blot away excess aqueous solution from the EM grid just prior to vitrification. The larger liposomes suspended within the sample preferentially wash away from the grid and into the filter paper, ending up in the filter paper. This is perhaps because the larger liposomes have larger surface areas that expose them to relatively larger forces during the rapid flow of the water to the filter paper. This makes them difficult to find and measure in electron micrographs when their relative concentration in the specimen is low, meaning that few are left behind after blotting. The second reason is that larger liposomes that are left behind on the EM grid, are often embedded in thicker ice that is too thick for the electron beam to either penetrate or, if it does, results in images that are too low in quality to provide adequate signal for image processing.5.1.2.3 Liposomal Distortion—Because liposomes are essentially loose membrane bounded fluid compartments, freezing them within a layer of vitrified ice that is thinner than their diameter may cause the surface tension on both sides of the specimen to compress some of the liposomes leading to various levels of flattening distortions. Accurate size measurements of such distorted liposomes would require volumetric measurements of all the liposomes within a field of view through a three-dimensional analysis using electron tomography.1.1 This practice covers procedures for vitrifying and recording images of a suspension of liposomes with a cryo-transmission electron microscope (cryo-TEM) for the purpose of evaluating their shape, size distribution and lamellarity for quality assessment. The sample is vitrified in liquid ethane onto specially prepared holey, ultra-thin, or continuous carbon TEM grids, and imaged in a cryo-holder placed in a cryo-TEM.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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 This microvacuum sampling and indirect analysis method is used for the general testing of non-airborne dust samples for asbestos. It is used to assist in the evaluation of dust that may be found on surfaces in buildings such as ceiling tiles, shelving, electrical components, duct work, carpet, etc. This test method provides an index of the surface loading of asbestos structures in the dust per unit area analyzed as derived from a quantitative TEM analysis.5.1.1 This test method does not describe procedures or techniques required to evaluate the safety or habitability of buildings with asbestos-containing materials, or compliance with federal, state, or local regulations or statutes. It is the user’s responsibility to make these determinations.5.1.2 At present, no relationship has been established between asbestos-containing dust as measured by this test method and potential human exposure to airborne asbestos. Accordingly, the users should consider other available information in their interpretation of the data obtained from this test method.5.2 This definition of dust accepts all particles small enough to pass through a 1-mm (No. 18) screen. Thus, a single, large asbestos containing particle(s) (from the large end of the particle size distribution) dispersed during sample preparation may result in anomalously large asbestos surface loading results in the TEM analyses of that sample. It is, therefore, recommended that multiple independent samples are secured from the same area, and that a minimum of three samples be analyzed by the entire procedure.1.1 This test method covers a procedure to (a) identify asbestos in dust and (b) provide an estimate of the surface loading of asbestos in the sampled dust reported as the number of asbestos structures per unit area of sampled surface.1.1.1 If an estimate of the asbestos mass is to be determined, the user is referred to Test Method D5756.1.2 This test method describes the equipment and procedures necessary for sampling, by a microvacuum technique, non-airborne dust for levels of asbestos structures. The non-airborne sample is collected inside a standard filter membrane cassette from the sampling of a surface area for dust which may contain asbestos.1.2.1 This procedure uses a microvacuuming sampling technique. The collection efficiency of this technique is unknown and will vary among substrates. Properties influencing collection efficiency include surface texture, adhesiveness, electrostatic properties and other factors.1.3 Asbestos identified by transmission electron microscopy (TEM) is based on morphology, selected area electron diffraction (SAED), and energy dispersive X-ray analysis (EDXA). Some information about structure size is also determined.1.4 This test method is generally applicable for an estimate of the surface loading of asbestos structures starting from approximately 1000 asbestos structures per square centimetre.1.4.1 The procedure outlined in this test method employs an indirect sample preparation technique. It is intended to disperse aggregated asbestos into fundamental fibrils, fiber bundles, clusters, or matrices that can be more accurately quantified by transmission electron microscopy. However, as with all indirect sample preparation techniques, the asbestos observed for quantification may not represent the physical form of the asbestos as sampled. More specifically, the procedure described neither creates nor destroys asbestos, but it may alter the physical form of the mineral fibers.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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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This microvacuum sampling and indirect analysis method is used for the general testing of non-airborne dust samples for asbestos. It is used to assist in the evaluation of dust that may be found on surfaces in buildings, such as ceiling tiles, shelving, electrical components, duct work, carpet, etc. This test method provides an estimate of the mass surface loading of asbestos in the dust reported as either the mass of asbestos per unit area or as the mass of asbestos per mass of sampled dust as derived from a quantitative TEM analysis.This test method does not describe procedures or techniques required to evaluate the safety or habitability of buildings with asbestos-containing materials, or compliance with federal, state, or local regulations or statutes. It is the user's responsibility to make these determinations.At present, no relationship has been established between asbestos-containing dust as measured by this test method and potential human exposure to airborne asbestos. Accordingly, the users should consider other available information in their interpretation of the data obtained from this test method.This definition of dust accepts all particles small enough to pass through a 1 mm screen. Thus, a single, large asbestos-containing particle(s) (from the large end of the particle size distribution) disassembled during sample preparation may result in anomalously large asbestos surface loading results in the TEM analyses of that sample. Conversely, failure to disaggregate large particles may result in anomalously low asbestos mass surface loadings. It is, therefore, recommended that multiple independent samples be secured from the same area, and that a minimum of three samples be analyzed by the entire procedure.1.1 This test method covers a procedure to (a) identify asbestos in dust and (b) provide an estimate of the surface loading of asbestos in the sampled dust, reported as either the mass of asbestos per unit area of sampled surface or as the mass of asbestos per mass of sampled dust.1.1.1 If an estimate of asbestos structure counts is to be determined, the user is referred to Test Method D 5755.1.2 This test method describes the equipment and procedures necessary for sampling, by a microvacuum technique, non-airborne dust for levels of asbestos. The non-airborne sample is collected inside a standard filter membrane cassette from the sampling of a surface area for dust which may contain asbestos.1.2.1 This procedure uses a microvacuuming sampling technique. The collection efficiency of this technique is unknown. Variability of collection efficiency for any particular substrate and across different types of substrates is also unknown. The effects of sampling efficiency differences and variability on the interpretation of dust sampling measurements have not been determined.1.3 Asbestos identified by transmission electron microscopy (TEM) is based on morphology, selected area electron diffraction (SAED), and energy dispersive X-ray analysis (EDXA). Some information about structure size is also determined.1.4 This test method is generally applicable for an estimate of the surface loading of asbestos starting from approximately 0.24 pg of asbestos per square centimetre (assuming a minimum fiber dimension of 0.5 μm by 0.025 μm, see 17.8), but will vary with the analytical parameters noted in 17.8.1.4.1 The procedure outlined in this test method employs an indirect sample preparation technique. It is intended to disaggregate and disperse asbestos into fibrils and fiber bundles that can be more accurately identified, counted, and sized by transmission electron microscopy. However, as with all indirect sample preparation techniques, the asbestos observed for quantitation may not represent the physical form of the asbestos as sampled. More specifically, the procedure described neither creates not destroys asbestos, but it may alter the physical form of the mineral fibers.1.5 The values stated in SI units are to be regarded as the 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 This test method is applicable to the measurement of airborne asbestos in a wide range of ambient air situations and for detailed evaluation of any atmosphere for asbestos structures. Most fibers in ambient atmospheres are not asbestos, and therefore, there is a requirement for fibers to be identified. Most of the airborne asbestos fibers in ambient atmospheres have diameters below the resolution limit of the light microscope. This test method is based on transmission electron microscopy, which has adequate resolution to allow detection of small thin fibers and is currently the only technique capable of unequivocal identification of the majority of individual fibers of asbestos. Asbestos is often found, not as single fibers, but as very complex, aggregated structures, which may or may not also be aggregated with other particles. The fibers found suspended in an ambient atmosphere can often be identified unequivocally if sufficient measurement effort is expended. However, if each fiber were to be identified in this way, the analysis would become prohibitively expensive. Because of instrumental deficiencies or because of the nature of the particulate matter, some fibers cannot be positively identified as asbestos even though the measurements all indicate that they could be asbestos. Therefore, subjective factors contribute to this measurement, and consequently, a very precise definition of the procedure for identification and enumeration of asbestos fibers is required. The method defined in this test method is designed to provide a description of the nature, numerical concentration, and sizes of asbestos-containing particles found in an air sample. The test method is necessarily complex because the structures observed are frequently very complex. The method of data recording specified in the test method is designed to allow reevaluation of the structure-counting data as new applications for measurements are developed. All of the feasible specimen preparation techniques result in some modification of the airborne particulate matter. Even the collection of particles from a three-dimensional airborne dispersion on to a two-dimensional filter surface can be considered a modification of the particulate matter, and some of the particles, in most samples, are modified by the specimen preparation procedures. However, the procedures specified in this test method are designed to minimize the disturbance of the collected particulate material.5.2 This test method applies to analysis of a single filter and describes the precision attributable to measurements for a single filter (see 13.1). Multiple air samples are usually necessary to characterize airborne asbestos concentrations across time and space. The number of samples necessary for this purpose is proportional to the variation in measurement across samples, which may be greater than the variation in a measurement for a single sample.1.1 This test method2 is an analytical procedure using transmission electron microscopy (TEM) for the determination of the concentration of asbestos structures in ambient atmospheres and includes measurement of the dimension of structures and of the asbestos fibers found in the structures from which aspect ratios are calculated.1.1.1 This test method allows determination of the type(s) of asbestos fibers present.1.1.2 This test method cannot always discriminate between individual fibers of the asbestos and non-asbestos analogues of the same amphibole mineral.1.2 This test method is suitable for determination of asbestos in both ambient (outdoor) and building atmospheres.1.2.1 This test method is defined for polycarbonate capillary-pore filters or cellulose ester (either mixed esters of cellulose or cellulose nitrate) filters through which a known volume of air has been drawn and for blank filters.1.3 The upper range of concentrations that can be determined by this test method is 7000 s/mm2. The air concentration represented by this value is a function of the volume of air sampled.1.3.1 There is no lower limit to the dimensions of asbestos fibers that can be detected. In practice, microscopists vary in their ability to detect very small asbestos fibers. Therefore, a minimum length of 0.5 μm has been defined as the shortest fiber to be incorporated in the reported results.1.4 The direct analytical method cannot be used if the general particulate matter loading of the sample collection filter as analyzed exceeds approximately 10 % coverage of the collection filter by particulate matter.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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5.1 This test method is applicable to the measurement of airborne carbon nanotubes in a wide range of ambient air situations and for evaluation of any atmosphere for carbon nanotube structures. Single carbon nanotube structures in ambient atmospheres have diameters below the resolution limit of the light microscope. This test method is based on transmission electron microscopy, which has adequate resolution to allow detection of small thin single carbon nanotubes and is currently a reliable technique capable of unequivocal identification of the majority of nanotube structures. Carbon nanotubes are often found, not as single carbon nanotubes, but as very complex, aggregated structures, which may or may not be aggregated with other particles.5.2 This test method applies to the analysis of a single filter and describes the precision attributable to measurements for a single filter. Multiple air samples are usually necessary to characterize airborne nanotube structure concentrations across time and space. The number of samples necessary for this purpose is proportional to the variation in measurement across samples, which may be greater than the variation in measurement for a single sample.1.1 This test method is an analytical procedure using transmission electron microscopy (TEM) for the determination of the concentration of carbon nanotubes and carbon nanotube-containing particles in ambient atmospheres.1.1.1 This test method is suitable for determination of carbon nanotubes in both ambient (outdoor) and building atmospheres.1.2 This test method is defined for polycarbonate capillary pore filters through which a known volume of air has been drawn and for blank filters.1.3 The direct analytical method cannot be used if the general particulate matter loading of the sample collection filter as analyzed exceeds approximately 25 % coverage of the collection filter by particulate matter.1.4 Units—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 A training program provides the theoretical foundation and practical skills necessary for a trainee to become a qualified forensic hair examiner.4.2 A trainee is directly supervised by a qualified examiner throughout their training. At the end of the training program, a successful trainee is capable of forming opinions, presenting and explaining evidence, and understanding the limitations of analytical results and interpretations based upon sound scientific knowledge, validated procedures, and practical experience.4.3 A trainee is required to meet the minimum training criteria in Practice E2917 and this practice. It is the laboratory management’s responsibility to ensure the selected trainee has the appropriate educational background. It is recommended that, at a minimum, the trainee possess a bachelor’s degree in a natural science.4.4 This document outlines lessons, practical exercises, and criteria to monitor and evaluate trainee progress and is designed to be incorporated into an overall laboratory training program.4.5 Additional training beyond that which is listed here should be made available to the trainee. Such training might include off-site courses, internships, and specialized training by experienced examiners. Continuing education and training will provide a forensic examiner the opportunity to remain current in the field.4.6 Additional analyses can be performed on hairs that have been chemically altered (for example, dyed hair) or have trace materials on the surface (for example, glitter). Such techniques are beyond the scope of this document.4.7 This practice addresses the benefit of following microscopical examinations with DNA analysis.1.1 This practice covers training guidelines for use by forensic laboratory personnel responsible for training forensic examiners that will perform hair examinations, including microscopical comparisons of human hair.1.2 Forensic hair examiners are trained in accordance with Practice E2917 and the discipline-specific guidelines (Guide E3316) and criteria within this practice.1.3 This practice contains guidelines that include the tasks, goals, and objectives that allow the trainee to acquire the requisite knowledge, skills, and abilities to independently perform casework in the microscopical examination of hair.1.4 This practice addresses the correlation between the analytical results of microscopical examinations and the potential for DNA analysis.1.5 This practice addresses training for the microscopical examination of hairs and not the examination of chemical alterations (for example, hair dye) or trace materials on the surface of hairs (for example, hair care products).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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Measurement of bacterial densities is generally the first step in establishing a relationship between bacteria and other biochemical processes. It is known that the classical plate count procedure underestimates bacterial densities while the epifluorescence direct microscopic procedure more accurately depicts the total numbers of nonviable or dormant and viable cells in a water sample. The acridine-orange INT-formazan reduction technique provides information on the total concentrations of bacteria as well as that proportion which are actively respiring and thus involved in degradative processes.The acridine-orange INT-formazan reduction technique is both quantitative and precise.This procedure is ideal for enumerating both pelagic and epibenthic bacteria in all fresh water and marine environments.The process can be employed in survey studies to characterize the bacteriological densities and activities of environmental waters.1.1 This test method covers the detection and enumeration of aquatic bacteria by the use of an acridine-orange epifluorescence direct-microscopic counting procedure. This test method is applicable to environmental waters and potable waters.1.2 Certain types of debris and other microorganisms may fluoresce in acridine-orange stained smears.1.3 The procedure described requires a trained microbiologist or technician who is capable of distinguishing bacteria from other fluorescing bodies on the basis of morphology when viewed at higher magnifications.1.4 Use of bright light permits differentiation of single bacteria where reduced formazan is deposited at the polar ends.1.5 Approximately 104 cells/mL are required for detection by this test method.1.6 Minimal cell size which allows the detection of formazan deposits is represented by bacteria of 0.4 μm.21.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard does not purport to address 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 Low temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) require high purity hydrogen for maximum material performance and lifetime. The particulates in hydrogen used in FCVs and hydrogen powered internal combustion vehicles may adversely affect pneumatic control components, such as valves or other critical system components. The visualization of the size and morphology of particles is an important tool for determining particle origin as well as for devising particle formation reduction strategies.1.1 This test method is primarily intended for visualizing and measuring the sizes and morphology of particulates in hydrogen used as a fuel for fuel cell or internal combustion engine powered vehicles. This test method describes procedures required to obtain size and morphology data of known quality. This test method can be applied to other gaseous samples requiring determination of particulate sizes and morphology provided the user’s data quality objectives are satisfied.1.2 Mention of trade names in standard does not constitute endorsement or recommendation. Other manufacturers of equipment, software or equipment models can be used.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.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 Bacterial populations, as part of the microbial community in aquatic systems are actively involved in nutrient cycling. The significance of these populations is often difficult to ascertain because of the presence of many physiological types. However, measurement of bacterial densities is usually the first step in trying to establish any relationship that might exist between bacteria and other biochemical processes.45.2 Acridine-orange epifluorescence direct-counting procedure cannot differentiate between viable and nonviable cells.5.3 This procedure cannot be used to convert directly the numbers to total carbon biomass because of the natural variations in bacterial cell size.5.4 The acridine-orange epifluorescence direct-microscopic count is both quantitative and precise.5.5 This procedure is ideal for enumerating both pelagic and epibenthic bacteria in all fresh water and marine environments.55.6 The process can be employed in survey activities to characterize the bacteriological densities of environmental waters.5.7 The procedure can also be used to estimate bacterial densities in cooling tower waters, process waters, and waters associated with oil drilling wells.1.1 This test method describes a procedure for detection and enumeration of aquatic bacteria by the use of an acridine-orange epifluorescence direct-microscopic counting procedure. It is applicable to environmental waters.1.2 Certain types of debris and other microorganisms may fluoresce in acridine orange-stained smears.1.3 The test method requires a trained microbiologist or technician who is capable of distinguishing bacteria from other fluorescing bodies on the basis of morphology when viewed at higher magnifications.21.4 Use of bright light permits differentiation of single bacteria where reduced formazan is deposited at the polar ends.1.5 Approximately 104 cells/mL are required for detection by this test method.21.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address 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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