5.1 This test method is intended for the measurement of gross alpha- and beta-activity concentrations in the analyses of environmental and drinking waters. For samples submitted to satisfy regulatory or permit requirements, the submitter should assure that this or any other method used is acceptable to the regulator or permit issuer.5.2 This test method is also applicable to the direct analysis of gross alpha- and beta-activity concentrations in water when low detection limits are not required. Direct analysis provides a rapid method for determination of gross alpha- and beta-activity concentrations when low detection limits are not required.5.3 This test method is not capable of discriminating among alpha emitting radionuclides or among beta emitting radionuclides. Those intending to identify and quantify specific radionuclides should use test methods specific to the radionuclides of interest.5.4 This test method may not be cited as a method for the determination of gross alpha- or beta-activity concentrations in a solid/soil matrix or the acid digestate of the same. The use of this test method for such applications brings the potential for serious bias and incomparability of results dependent on the matrix constituents, manner of sample preparation or treatment, or both.1.1 This test method covers the measurement of gross alpha- and beta- activity concentrations in a homogeneous water sample. It is applicable to alpha emitters with activity concentration levels above 0.11 Bq/L (3 pCi/L) and beta emitters with activity concentration levels above 0.15 Bq/L (4 pCi/L). This test method is not applicable to samples containing radionuclides that are volatile under conditions of the analysis.1.2 This test method may also be used for the direct measurement of gross alpha- and beta- activity concentrations in homogeneous water samples with alpha emitter activity concentration levels above 1.8 Bq/L (50 pCi/L) and beta emitter activity concentration levels above 3.7 Bq/L (100 pCi/L).1.3 This test method was tested using single-operator tests.2,3 A collaborative study following the U.S. EPA “Protocol for the Evaluation of Alternate Test Procedures for Analyzing Radioactive Contaminants in Drinking Water” was performed. The results of this study are on file at ASTM Headquarters.41.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to pCi/L that are provided for information only and are not considered standard. An exception is noted in Section 14.1.5 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 and health 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.

定价： 646元 / 折扣价： 550 元 加购物车

This specification covers alpha plus beta titanium alloy forgings for use in surgical implants such as orthopaedic medical devices. The products should be forged by hammering, pressing, extruding, or upsetting bars or wires and should be free of splits, scales, cracks, flaws, and other imperfections. After hot forging, each product should be subjected to annealing treatment consisting of heating the parts to an appropriate temperature and followed by cooling. Samples should be tested according to the specified procedure and should conform to the required values for chemical composition, tensile strength, hardness, elongation, and area reduction.1.1 This specification covers the requirements for titanium alloy forgings for surgical implants, in the alpha plus beta condition, when the material forged conforms to Specifications F136 (UNS R56401), F1295 (UNS R56700), F1472 (UNS R56400), or F2066 (UNS R58150).1.2 The SI units in this standard are the primary units. The values stated in either primary SI units or secondary 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 from the two systems may result in nonconformance with the 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： 515元 / 折扣价： 438 元 加购物车

This specification covers chemical and crystallographic requirements for biocompatible beta-tricalcium phosphate for surgical implant applications. Elemental analysis for calcium and phosphorus will be consistent with the expected stoichiometry of beta-tricalcium phosphate. The calcium and phosphorus content shall be determined using a suitable method such X-ray fluorescence. A quantitative X-ray diffraction analysis shall indicate a minimum beta-tricalcium phosphate content of 95 % as determined using powder diffraction method. The analysis of other trace elements may be required, based on the conditions, apparatus, or environment. It is recommended that all metals or oxides present in concentrations equal or greater than 0.1 % be noted in material descriptions.1.1 This specification covers chemical and crystallographic requirements for beta-tricalcium phosphate (β-TCP) raw materials intended for use in medical device applications. For a material to be identified as medical-grade beta-tricalcium phosphate, it must conform to this specification (see Appendix X1).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.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.

定价： 515元 / 折扣价： 438 元 加购物车

5.1 This test method was developed for the purpose of measuring the gross beta radioactivity in water. It is used for the analysis of both process and environmental water to determine gross beta activity.1.1 This test method covers the measurement of beta particle activity of water. It is applicable to beta emitters having maximum energies above 0.1 MeV and at activity levels above 0.02 Bq/mL (540 pCi/L) of radioactive homogeneous water for most counting systems. This test method is not applicable to samples containing radionuclides that are volatile under conditions of the analysis.1.2 This test method can be used for either absolute or relative determinations. In tracer work, the results may be expressed by comparison with a standard which is defined to be 100 %. For radioassay, data may be expressed in terms of a known radionuclide standard if the radionuclides of concern are known and no fractionation occurred during processing, or may be expressed arbitrarily in terms of some other standard such as 137Cs. General information on radioactivity and measurement of radiation may be found in the literature2, 3, 4, 5 and Practices D3648.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Zeolite Beta is a siliceous zeolite that can be crystallized with SiO2/Al2O3 ratio greater than 20. Zeolite Beta, upon modification to the H-cation form in a post-crystallization step, has been used in catalytic NOx reduction, isomerization of waxes, alkylation of aromatics, hydrocarbon adsorption from exhaust gas emission, etc.4.2 This X-ray procedure is designed to allow a reporting of the relative degree of crystallinity upon manufacture of zeolite Beta. The relative crystallinity of zeolite Beta 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 zeolite Beta can result from changes in distribution of electron density within the unit cell of the zeolite Beta. 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 zeolite Beta 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 quaternary ammonium cations that can function as a template for crystallization of the zeolite Beta structure.4.3.4 Because of the factors mentioned in 4.3.1 – 4.3.3 that could vary the intensities of the XRD peaks in zeolite Beta, this XRD method will provide the best determination of relative crystallinity when the reference zeolite Beta and sample zeolite Beta have a similar history of preparation and composition.4.4 If crystalline phases other than zeolite Beta are present in the sample, their diffraction peaks may overlap with some of the zeolite Beta 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 22.5° 2θ peak that is used for the calculation.1.1 This test method covers a procedure for determination of the relative crystallinity of zeolite Beta containing samples using selected peaks from the X-ray diffraction (XRD) 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 zeolite Beta to intensity of the corresponding portion of the pattern of a reference zeolite Beta. The intensity ratio, expressed as a percentage, is then labeled percent XRD relative crystallinity of zeolite Beta. 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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 The schedule beta (βs) approach produces informational elements: Overall (or composite) schedule beta (βs), schedule beta upside (βs+), and schedule beta downside (βs–)—representing the quantitative components, and the qualitative insight (“early warning”) into the propensity for directional schedule performance for individual schedule participants.5.1.1 The quantitative component of schedule beta (βs) (inclusive of the upside and downside subvariants) is an index value that depicts schedule participant’s magnitude and direction of movement as compared to the overall project at an assigned value of 1.0, for example, a βs = +2.5 connotes performance of a schedule participant that moves in the same direction as the collection of completed projects at a rate of 2.5 units (schedule days) for each single unit (schedule day) experienced at the overall project level.5.1.2 The qualitative component of schedule beta (βs) (inclusive of the upside and downside subvariants) provides insight as a cautionary and predictive signal depicting the ability for an individual schedule participant to perform in-keeping with the initially-established as-planned schedule duration(s).5.2 Schedule beta (βs) also depicts the overall status or health (performing well or not) of a market sector, location and/or trade. Consistent larger schedule beta (βs) values are indicative of external elements (risks) impacting all participants sharing common attribute(s) (that is, trade, location, market sector, etc.).5.3 Schedule beta (βs) measures current schedule participant performance. As a rolling value (for example, calculated for projects completed during the two most recently completed full calendar years), it depicts the schedule performance ability of the schedule participant. See Note 1.NOTE 1: Schedule Data Source and Usage—Schedule beta (βs) (inclusive of the upside and downside subvariants) utilizes schedule data from any schedule calculation method that depicts individual activity duration versus overall project duration and is updated on a regular basis. Data are used for calculation, comparison, and/or contrasting purposes. They are not created under this guide. Schedule beta (βs) uses four data points from the external scheduling method: as-planned and as-built durations for both individual activity and the overall construction project in its calculation – see Section 3 for definitions.5.3.1 Improving Values—Schedule beta (βs), schedule beta upside (βs+), and schedule beta downside (βs–) are characterized as improving when their value decreases in magnitude (that is, βs = +2.5 becomes βs = +1.75 and βs = –1.25 becomes βs = –3.0).5.3.2 Deteriorating Values—Schedule beta (βs), schedule beta upside (βs+), and schedule beta downside (βs–) are characterized as deteriorating when their value increases in magnitude (that is, βs = +0.5 becomes βs = +1. 5 and βs = –2.25 becomes βs = –1.0).5.4 Schedule beta (βs) (inclusive of the upside and downside subvariants) is capable of being calculated any time a project reaches completion and no further activity (no additional days) are recorded within an overall project schedule.5.4.1 Any schedule participant having completed their work in at least two (2) distinct (mutually exclusive) completed projects may calculate the full array of schedule beta values—schedule beta (βs), schedule beta upside (βs+), and schedule beta downside (βs–).1.1 This guide covers schedule beta (βs), which measures construction project participant schedule performance versus that of the overall completed project and is based on beta (β) from financial portfolio theory for measuring the correlation between individual stock performance and that of the overall stock market.2 By correlating the delta of actual activity performance (“as-built”) minus that originally scheduled (“as-planned”) to the delta of as-built minus as-planned for the overall completed project for a participant’s collection of projects over a specified period of time, a schedule performance index is established in a similar manner as the aforementioned beta (β) of an individual stock.1.2 Schedule beta (βs) measures, as a unitless index value, schedule participant (“subcontractor’s”) performance—ahead or behind—as-planned duration as correlated to its respective overall project’s schedule performance.1.3 Schedule beta (βs) is measured with input from at least two (2) independent (mutually exclusive) projects that have reached completion, within the defined period of observation.1.4 Schedule beta (βs) is measured across a standard predetermined period of time, in similar fashion to that of the insurance industry’s experience modification rate’s (EMR) most recent two (2) complete calendar years within the past thirty-six (36) months.1.5 Schedule beta (βs) evaluates schedule participant’s (“subcontractor’s”) most recent performance, not its complete history, such that is it indicative of current performance and contemporary influences—market, geographic, industry trade, etc.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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 The thickness or mass per unit area of a coating is often critical to its performance.4.2 For some coating-substrate combinations, the beta backscatter method is a reliable method for measuring the coating nondestructively.4.3 The test method is suitable for thickness specification acceptance if the mass per unit area is specified. It is not suitable for specification acceptance if the coating thickness is specified and the density of the coating material can vary or is not known.1.1 This test method covers the beta backscatter gages for the nondestructive measurement of metallic and nonmetallic coatings on both metallic and nonmetallic substrate materials.1.2 The test method measures the mass of coating per unit area, which can also be expressed in linear thickness units provided that the density of the coating is known.1.3 The test method is applicable only if the atomic numbers or equivalent atomic numbers of the coating and substrate differ by an appropriate amount (see 6.2).1.4 Beta backscatter instruments employ a number of different radioactive isotopes. Although the activities of these isotopes are normally very low, they can present a hazard if handled incorrectly. This standard does not purport to address the safety issues and the proper handling of radioactive materials. It is the responsibility of the user to comply with applicable State and Federal regulations concerning the handling and use of radioactive material. Some States require licensing and registration of the radioactive isotopes.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.

定价： 590元 / 折扣价： 502 元 加购物车