The efficiency of light-emitting diodes is known to vary with the carrier density of the starting material. This procedure provides a technique to prepare specimens in which the Hall carrier density can be measured in a region typical of that in which devices are fabricated. This quantity, which is related to the carrier density, can be used directly as a quality control parameter.Mobility is a function of a number of parameters of a semiconductor, including ionized impurity density, compensation, and lattice defects, some or all of which may be relatable to material quality as reflected in device quality. Use of this procedure makes the measurement of the mobility of the constant composition region possible.Since in GaAs (1−x)Px with x near 0.38, as is most often used for light-emitting diodes, the direct (000 or Γ) minimum and the indirect (100 or X) minima are within a few millielectronvolts in energy of each other, both are populated with current-carrying electrons. The mobility in the two bands is significantly different, and the relative population of the two is dependent upon the precise composition (x value), doping level, and temperature. Therefore, both Hall coefficient and Hall mobility must be interpreted with care (2,3). In particular, a measurement of Hall carrier density will not agree with a carrier density measurement on the same specimen made by capacitance-voltage techniques. Nevertheless, if the intent of measuring the carrier density of purchased or grown specimens is to find those which are optimum for diode fabrication, Hall measurements can be of value because a curve of efficiency versus Hall carrier density can be derived for the device process to be used based upon data taken on specimens prepared in accordance with this procedure.1.1 This practice covers a procedure to be followed to free the constant composition region of epitaxially grown gallium arsenide phosphide, GaAs(1x)Px, from the substrate and graded region on which it was grown in order to measure the electrical properties of only the constant composition region, which is typically 30 to 100 m thick. It also sets forth two alternative procedures to be followed to make electrical contact to the specimen.1.2 It is intended that this practice be used in conjunction with Test Methods F 76.1.3 The specific parameters set forth in this recommended practice are appropriate for GaAs0. 62P0. 38, but they can be applied, with changes in etch times, to material with other compositions.1.4 This practice does not deal with making or interpreting the Hall measurement on a specimen prepared as described herein, other than to point out the existence and possible effects due to the distribution of the free carriers among the two conduction band minima.1.5 This practice can also be followed in the preparation of specimens of the constant composition region for light absorption measurements or for mass or emission spectrometric analysis.1.6 This practice becomes increasingly difficult to apply as specimens become thinner.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For hazard statement, see Section 9 and 11.9.2.4.

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This test method is useful as an indicator of the susceptibility to moisture of compacted bitumen-aggregate mixtures. Note 1—The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Standard Practice are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with alone does not completely assure reliable results. Reliable results depend on many factors; following the suggestions of or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method covers measurement of the loss of compressive strength resulting from the action of water on compacted bituminous mixtures containing asphalt cement. A numerical index of reduced compressive strength is obtained by comparing the compressive strength of freshly molded and cured specimens with the compressive strength of duplicate specimens that have been immersed in water under prescribed conditions. 1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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3.1 Certain agencies who desire to use, store, or transport emulsified asphalt under less than ideal weather conditions may require that the product remain homogeneous (unbroken) after being subjected to a temperature of −18 °C.NOTE 1: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 Emulsified asphalt is normally damaged by freezing temperatures, but specially formulated materials are expected to pass this practice.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 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The effect of dynamic rolling load over resilient floor covering system is important since the resistance reflects the ability of a resilient floor covering system to properly perform under specific use or condition.4.2 Excessive rolling load over an installed resilient floor covering may cause floor covering system failures such as bond failure, delamination, and finish or coating deteriorations.4.3 The effect of dynamic rolling load shall be measured by qualitative evaluation comparing the tested assembly with a standard assembly.1.1 This practice covers the determination of the effect of dynamic rolling load over a resilient floor covering.1.2 This practice is intended to be used by resilient, adhesive and underlayment manufacturers to measure the impact of a dynamic rolling load over a specific product or a combination of products.1.3 This practice may be used to evaluate the performance of joints (sealed or welded) in the resilient floor covering.1.4 This practice may be used to aid in the diagnosis of a specific assembly performance and provide comparative evaluation.1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 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 The purpose of this practice is to outline a procedure for using GWT to locate areas in metal pipes in which wall loss has occurred due to corrosion or erosion.5.2 GWT does not provide a direct measurement of wall thickness, but is sensitive to a combination of the CSC and circumferential extent and axial extent of any metal loss. Based on this information, a classification of the severity can be assigned.5.3 The GWT method provides a screening tool to quickly identify any discontinuity along the pipe. Where a possible defect is found, follow-up inspection of suspected areas with ultrasonic testing or other NDT methods is normally required to obtain detailed thickness information, nature, and extent of damage.5.4 GWT also provides some information on the axial length of a discontinuity, provided that the axial length is longer than roughly a quarter of the wavelength of the excitation signal.5.5 The identification and severity assessment of any possible defects is qualitative only. An interpretation process to differentiate between relevant and non-relevant signals is necessary.5.6 This practice only covers the application specified in the scope. The GWT method has the capability and can be used for applications where the pipe is insulated, buried, in road crossings, and where access is limited.5.7 GWT shall be performed by qualified and certified personnel, as specified in the contract or purchase order. Qualifications shall include training specific to the use of the equipment employed, interpretation of the test results and guided wave technology.5.8 A documented program that includes training, examination and experience for the GWT personnel certification shall be maintained by the supplying party.1.1 This practice provides a procedure for the use of guided wave testing (GWT), also previously known as long range ultrasonic testing (LRUT) or guided wave ultrasonic testing (GWUT).1.2 GWT utilizes ultrasonic guided waves, sent in the axial direction of the pipe, to non-destructively test pipes for defects or other features by detecting changes in the cross-section or stiffness of the pipe, or both.1.3 GWT is a screening tool. The method does not provide a direct measurement of wall thickness or the exact dimensions of defects/defected area; an estimate of the defect severity however can be provided.1.4 This practice is intended for use with tubular carbon steel or low-alloy steel products having Nominal Pipe size (NPS) 2 to 48 corresponding to 60.3 mm to 1219.2 mm (2.375 in. to 48 in.) outer diameter, and wall thickness between 3.81 mm and 25.4 mm (0.15 in. and 1 in.).1.5 This practice covers GWT using piezoelectric transduction technology.1.6 This practice only applies to GWT of basic pipe configuration. This includes pipes that are straight, constructed of a single pipe size and schedules, fully accessible at the test location, jointed by girth welds, supported by simple contact supports and free of internal, or external coatings, or both; the pipe may be insulated or painted.1.7 This practice provides a general procedure for performing the examination and identifying various aspects of particular importance to ensure valid results, but actual interpretation of the data is excluded.1.8 This practice does not establish an acceptance criterion. Specific acceptance criteria shall be specified in the contractual agreement by the responsible system user or engineering entity.1.9 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.10 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.1.11 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 can be used to test asphalt mixtures in conjunction with mixture design testing to determine the potential for moisture damage, to determine whether or not an antistripping additive is effective, and to determine what dosage of an additive is needed to maximize the effectiveness. This test method can also be used to test mixtures produced in plants to determine the effectiveness of additives under the conditions imposed in the field.NOTE 1: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method covers procedures for preparing and testing laboratory-compacted asphalt mixture specimens for the purpose of measuring the effect of water on the tensile strength of the paving mixture. This test method is applicable to dense mixtures such as those appearing in the Table for Composition of Bituminous Paving Mixtures in Specification D3515. This test method can be used to evaluate the effect of moisture with or without antistripping additives including liquids and pulverulent solids such as hydrated lime or portland cement.1.2 The values stated in either SI units or inch-pound units in brackets shall be regarded separately as standard. The values in each system may not be exact equivalents; therefore, each system must be used independently of the other, without combining values in any way.1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This practice should be used whenever measured color-scale or color-difference-scale values are to be compared to an established tolerance. In this way it can be demonstrated quantitatively that the sampling and measurement procedures are adequate to allow an unambiguous decision as to whether or not the mean results are within tolerance.5.2 This practice is based on portions of SAE J 1545, as it applies to painted or plastic automotive parts. It is generally applicable to object colors in various materials. Textured materials, such as textiles, may require special consideration (see SAE J 1545 and STP 15D Manual on Presentation of Data and Control Chart Analysis5).5.3 While Practice E178 deals with outliers, it does not include definitions relating to the box and whisker technique. The definition of an outlier is operational and a little vague because there is still considerable disagreement about what constitutes an outlier. In any normally distributed population, there will be members that range from minus to plus infinity. Theoretically, one should include any member of the population in any sample based on estimates of the population parameters. Practically, including a member that is found far from the mean within a small sample, most members of which are found near the mean, will introduce a systematic bias into the estimate of the population parameters (mean, standard deviation, standard error). Such a bias is in direct contrast with the goal of this practice, namely, to reduce the effects of variability of measurement. For the purposes of this practice, no distinction is made between errors of sampling and members of the tails of the distribution. Practice E178 has several methods and significance tables to attempt to differentiate between these two types of extreme values.1.1 Reduction of the variability associated with average color or color-difference measurements of object-color specimens is achieved by statistical analysis of the results of multiple measurements on a single specimen, or by measurement of multiple specimens, whichever is appropriate.1.2 This practice provides a means for the determination of the number of measurements required to reduce the variability to a predetermined fraction of the relevant color or color-difference tolerances.1.3 This practice is general in scope rather than specific as to instrument or material.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method is used to measure viscoelastic properties through the strain softening effects of a strain amplitude sweep (the Payne Effect).5.2 For the uncured state, the time conditioning and strain amplitude strain sweeps can relate to colloidal silica particle or carbon black deagglomeration from the mixing process. The profile of this Payne Effect from G’ storage modulus can also be a function of loading levels and particle size of these fillers in the rubber hydrocarbon medium. In addition, with silica and an organosilane additive, this G’ strain softening effect can determine if a given silanization reaction between a subject silica and an organosilane was achieved through reactive mixing. If the silanization reaction during the mixing was not achieved, the maximum G’ storage modulus from the strain sweep will not be lowered and the silica particle attraction to other silica particles will still be high resulting in a more dense filler network that remains.1.1 This test method covers the use of a sealed cavity rotorless oscillating shear rheometer for the measurement of the softening effects of rising sinusoidal strain when applied to an unvulcanized rubber compound containing significant amounts of colloidal fillers (such as silica or carbon black, or both) from a rubber mixing procedure. These strain softening properties relate to mixing conditions, the composition of the rubber compound, colloidal particle (Payne Effect) characteristics of the fillers, and in some cases the degree of reaction between an organosilane and precipitated, hydrated silica during mixing. This procedure is being commonly applied to rubber reactive mixing procedures.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.

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5.1 The use of this apparatus is intended to induce property changes associated with the end-use conditions, including the effects of the UV portion of sunlight, moisture, and heat. Exposures are not intended to simulate the deterioration caused by localized weather phenomena, such as atmospheric pollution, biological attack, and saltwater exposure.NOTE 3: Refer to Practice G151 for cautionary guidance applicable to laboratory weathering devices.5.2 Variation in results may be expected when operating conditions are varied within the accepted limits of this method.5.3 Test data for one thickness of a geomembrane cannot be used as data for other thickness geomembranes made with the same formula (polymer, pigment, and stabilizers) since the degradation is thickness related.NOTE 4: It is recommended that a similar material of known performance (a control) be exposed simultaneously with the test material to provide a standard for comparative purposes. When control material is used in the test program, it is recommended only one coupon be used for each UV exposure period to allow for OIT testing.1.1 This standard covers the specific procedures and test conditions that are applicable for exposure of unreinforced polyolefin geomembranes to fluorescent UV radiation and condensation.NOTE 1: Polyolefin geomembranes include high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), flexible polyproplyene (fPP), etc.1.2 Test specimens are exposed to fluorescent UVA-340 lamps under controlled environmental conditions. UVA-340 lamps are standard for this method.NOTE 2: Other types of fluorescent UV lamps, such as UVB-313, can also be used based upon discussion between involved parties. However, if the test is run with another type of fluorescent UV lamp, such as UVB-313, this should be considered as a deviation from the standard and clearly stated in the test report. UVB-313 and UVA-340 fluorescent lamps generate different amounts of radiant power in different wavelength ranges; thus, the photochemical effects caused by these different lamps may vary.1.3 This method covers the conditions under which the exposure is to be performed and the test methods for evaluating the effects of fluorescent UV, heat, and moisture in the form of condensation on geomembranes. General guidance is given in Practices G151 and G154.1.4 The values listed in SI units are to be regarded as the 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 This practice may be used to determine the performance, for suitable materials, in terms of any desired strength property of adhesive bonds. Test conditions of temperature and moisture only are here specified. The duration of exposure is dependent upon the nature of the adhesive and the type of specimens and will, therefore, be covered by material specifications.1.1 This practice defines conditions for determining the performance of adhesive bonds when subjected to continuous exposure at specified conditions of moisture and temperature. The performance is expressed as a percentage based on the ratio of strength retained after exposure to the original strength.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes 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： 515元 / 折扣价： 438 元 加购物车

5.1 Stem cells of hematopoietic origin are pluripotential and may be particularly sensitive to the effects of stimulation by nanoparticulate materials.5.2 The effect of particles on macrophage responses has an extensive history and can be assessed by Practice F1903. The test method described here will assess the effect on stem cells which can be progenitor cells to the macrophage line.1.1 This test method provides a protocol for quantitative analysis of the effect of nanoparticulate materials in physiologic solution (isotonic, pH 7.2 ± 0.2) on granulocyte-macrophage colony-forming units (CFU-GM).1.2 CFU-GM reflects the number of viable bone marrow cells which differentiate into granulocytes and macrophages. A decrease in CFU-GM count is indicative of a test substance’s toxicity to bone marrow and is commonly used for the identification of drug products with myelosuppressive properties, a form of immunosuppression.1.3 This test method employs murine bone marrow hematopoietic stem cells which proliferate and differentiate to form discrete cell clusters or colonies which are counted.1.4 This test method is part of the in vitro preclinical characterization cascade for nanoparticulate materials for systemic administration in medical applications.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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3.1 Vibration encountered in the field is usually random in nature and this test can be used to determine the effects of random excitation on the membrane switch.3.2 Random vibration can cause mechanical fatigue and failure by switch components either loosening or otherwise changing over time.3.3 Experience has shown that this test will expose potential failures associated with the electronic components of a membrane switch, where tests of lower levels will not.3.4 This practice can be used to qualify a membrane switch for aerospace, medical and other applications.3.5 This test is potentially destructive, intended for device qualification.1.1 This test method establishes procedures for determining the effect of random vibration, within the specified frequency range, on switch contacts, mounting hardware, adhered component parts, solder or heat stakes, tactile devices, and cable or ribbon interconnects associated with a membrane switch or membrane switch assembly.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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