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4.1 ZSM-5 is a siliceous zeolite that can be crystallized with SiO2/Al2O3 ratio in the range of 20 to greater than 1000. ZSM-5, upon modification to the H-cation form (HZSM-5) in a post-crystallization step, has been used since the 1970s as a shape selective, acid-site catalyst for petroleum refining and petrochemicals production, including such processes as alkylation, isomerization, fluid cracking catalysis (FCC), and methanol-to-gasoline. The most siliceous member of the ZSM-5 family, sometimes called silicalite, is hydrophobic and it is used for selective sorption of organic molecules from water-containing systems.4.2 This X-ray procedure is designed to allow a reporting of the relative degree of crystallization upon manufacture of ZSM-5. The relative crystallinity/ZSM-5 number has proven useful in technology, research, and specifications.4.3 The Integrated Peak Area Method (Procedure A) is preferred over the Peak Height Method (Procedure B) since it calculates XRD intensity as a sum from several peaks rather than utilizing just one peak. Drastic changes in intensity of individual peaks in the XRD pattern of ZSM-5 can result from changes in distribution of electron density within the unit cell of the ZSM-5 zeolite. The electron density distribution is dependent upon the following factors:4.3.1 Extent of filling of pores with guest molecules and the nature of these guest molecules.4.3.2 Type of cations and extent of their presence (these cations may also affect the absorption of X rays by the ZSM-5 sample).4.3.3 In this XRD method, the guest molecule H2O completes the filling of the pores. Other guest molecule types may also be present, including one of numerous amines, diamines, and quarternary ammonium cations that can function as a template for crystallization of the ZSM-5 structure.4.3.4 Because of the factors mentioned in 4.3.1 to 4.3.3 that could vary the intensities of the XRD peaks in ZSM-5, this XRD method will provide the best determination of relative crystallinity when the reference ZSM-5 and sample ZSM-5 have a similar history of preparation and composition.4.4 ZSM-5 can exist with either orthorhombic or monoclinic symmetry, depending upon the composition of the precursor gel or post-crystallization modification conditions, or both. In the orthorhombic type, the XRD peaks centered at about 23.1 and 23.8° 2θ are usually split into doublets, whereas the less symmetric monoclinic type may show a further split of these peaks into triplets. The peak area intensities of these peaks are unaffected by the crystalline form. The XRD peak at 24.3° 2θ for the orthorhombic form is a singlet and hence is the most suitable for the Peak Height Method (Procedure B). If the 24.3° peak is split (doublet in the monoclinic form), then the Integrated Peak Area Method (Procedure A) should be used.4.5 If crystalline phases other than ZSM-5 are present in the sample, their diffraction peaks may overlap with some of the ZSM-5 peaks selected for the Integrated Peak Area Method (Procedure A). If there is reason to suspect the presence of such components, then the Peak Height Method (Procedure B) should be chosen for analysis provided that there is no interference with the 24.3° 2θ peak that is used for the calculation.1.1 This test method covers a procedure for determination of the relative crystallinity of zeolite ZSM-5 using selected peaks from the X-ray diffraction pattern of the zeolite.1.2 The test method provides a number that is the ratio of intensity of a portion of the XRD pattern of the sample ZSM-5 to intensity of the corresponding portion of the pattern of a reference ZSM-5. The intensity ratio, expressed as a percentage, is then labeled percent XRD relative crystallinity/ZSM-5. This type of comparison is commonly used in zeolite technology and is often referred to as percent crystallinity.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 One of the factors affecting the quality of radiologic images is the geometric unsharpness. The degree of geometric unsharpness is dependent on the focal spot size of the radiation source, the distance between the source and the object to be radiographed, and the distance between the object to be radiographed and the detector (imaging plate, Digital Detector Array (DDA) or film). This test method allows the user to determine the effective focal size of the X-ray source. This result may then be used to establish source to object and object to detector distances appropriate for maintaining the desired degree of geometric unsharpness or maximum magnification for a given radiographic imaging application, or both. Some ASTM standards require this value for calculation of a required magnification, for example, Practices E1255, E2033, and E2698.1.1 The image quality and the resolution of X-ray images are especially sensitive to the characteristics of the focal spot. The imaging qualities of the focal spot are based on its two dimensional intensity distribution as seen from the detector plane.1.2 This test method provides instructions for determining the effective size (dimensions) of standard and mini focal spots of industrial X-ray tubes for focal spot dimensions from 100 μm up to several mm of X-ray sources up to 600 kV tube voltage. Smaller focal spots down to 50 µm could be evaluated with less precision. This determination is based on the measurement of an image of a focal spot that has been radiographically recorded with a “pinhole” technique. An alternative method with a plaque hole IQI may be found in the Annex A, which covers the same focal spot sizes.1.3 Smaller focal spots should be measured using Test Method E2903 using the projection of an edge.1.4 This test method may also be used to determine the change in focal spot size that may have occurred due to tube age, tube overloading, and the like. This would entail the production of a focal spot radiograph (with the pinhole method) and an evaluation of the resultant image for pitting, cracking, and the like.1.5 Units—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, 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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ASTM D4962-18 Standard Practice for NaI(Tl) Gamma-Ray Spectrometry of Water Active 发布日期 :  1970-01-01 实施日期 : 

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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 This practice describes the essential components of a wavelength dispersive X-ray spectrometer. This description is presented so that the user may gain a general understanding of the structure of an X-ray spectrometer system. It also provides a means for comparing and evaluating different systems as well as understanding the capabilities and limitations of each instrument.4.2 A laboratory may implement this practice or an X-ray fluorescence method in partnership with a manufacturer of the analytical instrumentation. If a laboratory chooses to consult with an instrument manufacturer, then the following should be considered. The laboratory should know the alloy matrices to be analyzed, elements and mass fraction ranges to be determined, and the expected performance requirements for each of these elements. The laboratory should inform the instrument manufacturer of these requirements so an analytical method may be developed which meets the laboratory’s expectations. Typically, instrument manufacturers customize the instrument configuration to satisfy the end-user’s requirements for elemental coverage, elemental precision, and detection limits. Instrument manufacturer developed analytical methods may include specific parameters for sample excitation, wavelengths, inter-element interference corrections, calibration and regression, equipment configuration/installation, and sample preparation requirements. Laboratories should have a basic understanding of the parameters derived by the manufacturer.1.1 This practice covers the components of a wavelength dispersive X-ray spectrometer that are basic to its operation and to the quality of its performance. It is not the intent of this practice to specify component tolerances or performance criteria, as these are unique for each instrument. However, the practice does attempt to identify which tolerances are critical and thus which should be specified.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific safety hazard statements are given in Section 7.1.3 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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Uranium production facilities must control trace uranium content in their waste waters.Colorimetric and fluorimetric methods have been developed but require a tedious separation of interfering elements. Trace uranium can also be determined by ICP-MS but not all water matrices are adapted (for example, waters with high salt content). Direct X-ray fluorescence can be done on the liquid but with a detection limit of ∼5 mg/LX-ray fluorescence after collection of uranium offers the advantages to reach low detection limits (0.05 mg/L) and to avoid handling a liquid in the spectrometer.1.1 This test method applies for the determination of trace uranium content in waste water. It covers concentrations of U between 0.05 mg/L and 2 mg/L.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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3.1 Accurate elemental analyses of samples of petroleum and petroleum products are required for the determination of chemical properties, which are in turn used to establish compliance with commercial and regulatory specifications.1.1 This practice covers information relating to sampling, calibration and validation of X-ray fluorescence instruments for elemental analysis, including all kinds of wavelength dispersive (WDXRF) and energy dispersive (EDXRF) techniques. This practice includes sampling issues such as the selection of storage vessels, transportation, and sub-sampling. Treatment, assembly, and handling of technique-specific sample holders and cups are also included. Technique-specific requirements during analytical measurement and validation of measurement for the determination of trace elements in samples of petroleum and petroleum products are described. For sample mixing, refer to Practice D5854. Petroleum products covered in this practice are considered to be a single phase and exhibit Newtonian characteristics at the point of sampling.1.2 Applicable Test Methods—This practice is applicable to the XRF methods under the jurisdiction of ASTM Subcommittee D02.03 on Elemental Analysis, and those under the jurisdiction of the Energy Institute’s Test Method Standardization Committee (Table 1). Some of these methods are technically equivalent though they may differ in details (Table 2).1.3 Applicable Fluids—This practice is applicable to petroleum and petroleum products with vapor pressures at sampling and storage temperatures less than or equal to 101 kPa (14.7 psi). Use Practice D4057 or IP 475 to sample these materials. Refer to Practice D5842 when sampling materials that also require Reid vapor pressure (RVP) determination.1.4 Non-applicable Fluids—Petroleum products whose vapor pressure at sampling and sample storage conditions are above 101 kPa (14.7 psi) and liquefied gases (that is, LNG, LPG, etc.) are not covered by this practice.1.5 Sampling Methods—The physical sampling and methods of sampling from a primary source are not covered by this guide. It is assumed that samples covered by this practice are a representative sample of the primary source liquid. Refer to Practice D4057 or IP 475 for detailed sampling procedures.1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.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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ASTM D4452/D4452M-22 Standard Practice for X-Ray Radiography of Soil Samples Active 发布日期 :  1970-01-01 实施日期 : 

5.1 Many geotechnical tests require the utilization of intact, representative samples of soil. The quality of these samples depends on many factors. Many of the samples obtained by intact sampling methods have inherent anomalies. Sampling procedures cause disturbances of varying types and intensities. These anomalies and disturbances, however, are not always readily detectable by visual inspection of the intact samples before or after testing. Often test results would be enhanced if the presence and the extent of these anomalies and disturbances are known before testing or before destruction of the sample by testing. Such determinations assist the user in detecting flaws in sampling methods, the presence of natural or induced shear planes, and the presence of natural intrusions, such as gravels or shells at critical regions in the samples, the presence of sand and silt seams, and the intensity of disturbances caused by sampling.5.2 X-ray radiography provides the user with a picture of the internal massive structure of the soil sample, regardless of whether the soil is X-rayed within or without the sampling tube. X-ray radiography assists the user in identifying the following:5.2.1 Appropriateness of sampling methods used.5.2.2 Effects of sampling in terms of the disturbances caused by the turning of the edges of various thin layers in varved soils, large disturbances caused in soft soils, shear planes induced by sampling, or extrusion, or both, effects of overdriving of samplers, the presence of cuttings in sampling tubes, or the effects of using bent, corroded, or nonstandard tubes for sampling.5.2.3 Naturally occurring fissures, shear planes, etc.5.2.4 The presence of intrusions within the sample, such as calcareous nodules, gravel, or shells.5.2.5 Sand and silt seams, organic matter, large voids, and channels developed by natural or artificial leaching of soil components.NOTE 1: The quality of the results 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 ensure reliable testing. Reliable testing depends on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers the determination of the quality of soil samples in thin wall tubes or of extruded soil cores by X-ray radiography.1.2 This practice enables the user to determine the effects of sampling and natural variations within samples as identified by the extent of the relative penetration of X-rays through soil samples.1.3 This practice can be used to X-ray soil cores (or observe their features on a fluoroscope) in thin wall tubes or liners ranging from approximately 50 to 150 mm [2 to 6 in.] in diameter. X-rays of samples in the larger diameter tubes provide a radiograph of major features of soils and disturbances, such as large scale bending of edges of varved clays, shear planes, the presence of large concretions, silt and sand seams thicker than 6 mm [1/4 in.], large lumps of organic matter, and voids or other types of intrusions. X-rays of the smaller diameter cores provide higher resolution of soil features and disturbances, such as small concretions (3 mm [1/8 in.] diameter or larger), solution channels, slight bending of edges of varved clays, thin silt or sand seams, narrow solution channels, plant root structures, and organic matter. The X-raying of samples in thin wall tubes or liners requires minimal preparation.1.4 Greater detail and resolution of various features of the soil can be obtained by X-raying extruded soil cores, as compared to samples in metal tubes. The method used for X-raying soil cores is the same as that for tubes and liners, except that extruded cores have to be handled with extreme care and have to be placed in sample troughs (similar to Fig. 2) before X-raying. This practice should be used only when natural water content or other intact soil characteristics are irrelevant to the end use of the sample.1.4.1 Often it is necessary to obtain greater resolution of features to determine the propriety of sampling methods, the representative nature of soil samples, or anomalies in soils. This practice requires that either duplicate samples be obtained or already tested specimens be X-rayed.1.5 This practice can only be used to its fullest extent after considerable experience is obtained through many detailed comparisons between the X-ray image and the sample X-rayed.1.6 Units—The values stated in either SI units or inch-pound units [presented in brackets] 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 from the two systems may result in nonconformance with standard.1.7  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 this 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 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.1.8 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.8.1 For purposes of comparing, a measured or calculated value(s) with specified limits, the measured or calculated value(s) shall be rounded to the nearest decimal or significant digits in the specified limits.1.8.2 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the signification digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.1.9 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 precaution statements, see Section 7.1.10 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 One of the factors affecting the image quality of a radiographic image is geometric unsharpness. The degree of geometric unsharpness is dependent upon the focal spot size of the radiation source, the distance between the source and the object to be radiographed, the distance between the object to be radiographed and the image plane (film, imaging plate, Digital Detector Array (DDA), or radioscopic detector). This test method allows the user to determine the effective focal spot size (dimensions) of the X-ray source. This result can then be used to establish source to object and object to image detector distances appropriate for maintaining the desired degree of geometric unsharpness or maximum magnification possible, or both, for a given radiographic imaging application. The accuracy of this method is dependent upon the spatial resolution of the imaging system, magnification, and signal-to-noise of the resultant images.1.1 The image quality and the resolution of X-ray images highly depend on the characteristics of the focal spot. The imaging qualities of the focal spot are based on its two dimensional intensity distribution as seen from the imaging place.1.2 This test method provides instructions for determining the effecting size (dimensions) of mini and micro focal spots of industrial X-ray tubes. It is based on the European standard, EN 12543–5, Non-destructive testing - Characteristics of focal spots in industrial X-ray systems for use in non-destructive testing - Part 5: Measurement of the effective focal spot size of mini and micro focus X-ray tubes.1.3 This standard specifies a method for the measurement of effective focal spot dimensions from 5 up to 300 μm of X-ray systems up to and including 225 kV tube voltage, by means of radiographs of edges. Larger focal spots should be measured using Test Method E1165 Standard Test Method for Measurement of Focal Spots of Industrial X-Ray Tubes by Pinhole Imaging.1.4 The same procedure can be used at higher kilovoltages by agreement, but the accuracy of the measurement may be poorer.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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