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6.1 This test method is useful for research and development, quality assurance, regulatory compliance and specification-based acceptance.6.2 The kinetic parameters determined by this method may be used to calculate thermal hazard figures-of-merit according to Practice E1231.1.1 This test method describes the determination of the kinetic parameters of Arrhenius activation energy and pre-exponential factor using the Kissinger variable heating rate iso-conversion method (1, 2)2 and activation energy and reaction order by the Farjas method (3) for thermally unstable materials. The test method is applicable to the temperature range from 300 K to 900 K (27 °C to 627 °C).1.2 Both nth order and accelerating reactions are addressed by this method over the range of 0.5 < n < 4 and 1 < p < 4 where n is the nth order reaction order and p is the Avrami reaction order (4). Reaction orders n and p are determined by the Farjas method (3).1.3 This test method uses the same experimental conditions as Test Method E698. The Flynn/Wall/Ozawa data treatment of Test Method E698 may be simultaneously applied to these experimental results.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Information concerning the reaction model aids in the selection of the appropriate method (and test method) for evaluation of kinetic parameters. nth order reaction may be treated by isoconversion methods such as Test Methods E698 and E2890. Autocatalytic reactions are treated by Test Methods E2070.5.2 This practice may be used in research, forensic analysis, trouble shooting, product evaluation, and hazard potential evaluation.1.1 This practice describes a procedure for determining the “model” of an exothermic reaction using differential scanning calorimetry. The procedure is typically performed on 1 mg to 3 mg specimen sizes over the temperature range from ambient to 600 °C.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method measures the time to extrapolated onset of an exothermic reaction under constant temperature (isothermal) conditions for reactions which have an induction period, for example, those which are catalytic, autocatalytic, or accelerating in nature or which contain reaction inhibitors.5.2 The RIT determined by this test method is an index measurement that is useful for comparing one material to another at the test temperature of interest and in the same apparatus type only.5.3 This test method is a useful adjunct to dynamic thermal tests, such as Test Method E537, which are performed under conditions in which the sample temperature is increased continuously at constant rate. Results obtained under dynamic test conditions may result in higher estimates of temperature at which an exothermic reaction initiates because the detected onset temperature is dependent upon the heating rate and because dynamic methods allow insufficient time for autocatalytic reactions to measurably affect the onset temperature.5.4 RIT values determined under a series of isothermal test conditions may be plotted as their logarithm versus the reciprocal of the absolute temperature to produce a plot, the slope of which is proportional to the activation energy of the reaction as described in Test Methods E2070.5.5 This test method may be used in research and development, manufacturing, process and quality control, and regulatory compliance.5.6 This test method is similar to that for oxidation induction time (OIT) (for example, Specification D3350 and Test Methods D3895, D4565, D5483, D6186, and E1858) where the time to the oxidation reaction under isothermal test conditions is measured. The OIT test method measures the presence of antioxidant packages and is a relative measurement of a material’s resistance to oxidation.1.1 This test method describes the measurement of reaction induction time (RIT) of chemical materials that undergo exothermic reactions with an induction period. The techniques and apparatus described may be used for solids, liquids, or slurries of chemical substances. The temperature range covered by this test method is typically from ambient to 400 °C. This range may be extended depending upon the apparatus used.1.2 The RIT is a relative index value, not an absolute thermodynamic property. As an index value, the RIT value may change depending upon experimental conditions. A comparison of RIT values may be made only for materials tested under similar conditions of apparatus, specimen size, and so forth. Furthermore, the RIT value may not predict behavior of large quantities of material.1.3 The RIT shall not be used by itself to establish a safe operating temperature. It may be used in conjunction with other test methods (for example, Test Methods E487 and E537, and Guide E1981) as part of a hazard analysis of a particular operation.1.4 This test method may be used for RIT values greater than 15 min (as relative imprecision increases at shorter periods).1.5 This test method is used to study catalytic, autocatalytic, and accelerating reactions. These reactions depend upon time as well as temperature. Such reactions are often studied by fixing one experimental parameter (that is, time or temperature) and then measuring the other parameter (that is, temperature or time). This test method measures time to reaction onset detection under isothermal conditions. It is related to Test Method E487 that measures detected reaction onset temperature under constant time conditions1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this test method.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This guide is intended for use in any laboratory utilizing PCR or RT-PCR to amplify and detect nucleic acid sequences of mycobacteria from a biological preparation and to identify the species of origin.The criteria used for the identification and evaluation of the amplification reactions should be administered by an individual trained in the use of molecular biological and microbiological techniques associated with PCR and MTB.1.1 This guide covers basic considerations, criteria, principles and recommendations that should be helpful when developing, utilizing, or assessing PCR-specific protocols for the amplification and detection or identification of mycobacterial nucleic acids. This guide is not a specific protocol for the detection of specific mycobacteria. It is intended to provide information that will assist the user in obtaining high quality and reliable data. The guide is closely related to and should be used concurrently with the general PCR Guide E 1873.1.2 This guide has been developed for use in any molecular biology or biotechnology laboratory. It may be useful for the detection of mycobacteria in clinical, diagnostic laboratories.1.3 This guide does not cover details of the various methods such as gel electrophoresis that can be utilized to help identify PCR-amplified mycobacterial nucleic acid sequences, and it does not cover details of instrument calibration.1.4 This guide does not cover specific variations of the basic PCR or RT-PCR technology (for example, quantitative PCR, multiplex PCR and in situ PCR), and it does not cover details of instrument calibration.1.5 Warning-Laboratory work involving certain clinical specimens and microorganisms can be hazardous to personnel. Precaution: Biosafety Level 2 facilities are recommended for potentially hazardous work, and Biosafety Level 3 facilities are required for propagating and manipulating Mycobacteria tuberculosis cultures (). Safety guidelines should be adhered to according to NCCLS M29-T2, I17-P and other recommendations ().

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5.1 Both NO2 and NO play an important role in photochemical-smog-forming reactions. In sufficient concentrations NO2 is deleterious to health, agriculture, materials, and visibility.5.2 In combustion processes, significant amounts of NO may be produced by combination of atmospheric nitrogen and oxygen; at ambient temperatures, NO can be converted to NO2 by oxygen and other atmospheric oxidants. Nitrogen dioxide also may be generated from processes involving nitric acid, nitrates, the use of explosives, and welding.1.1 This test method covers the manual determination of the combined nitrogen dioxide (NO2) and nitric oxide (NO) content, total NOx; in the atmosphere in the range from 4 to 10 000 μg/m3 (0.002 to 5 ppm (v)).1.2 The maximum sampling period is 60 min at a flow rate of 0.4 L/min.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.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 Although Test Method D4017 is widely used for the determination of water in paints and related materials, this method may overcome some of the variability found in the Karl Fischer method.4.2 Control of water content is often important in controlling the performance of paints, and it is critical in determining volatile organic compound (VOC) content when VOC content is measured by difference from total volatile matter and water content as required in certain federal and state regulations.1.1 This test method describes the determination of the total water content of paints using a calcium hydride reaction test kit, or water content between 2 and 85 % water.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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4.1 This test method can be extended to use any material that has the necessary nuclear and activation properties that suit the experimenter's particular situation. No attempt has been made to fully describe the myriad problems of counting techniques, neutron-fluence depression, and thick-foil self-shielding. It is assumed that the experimenter will refer to existing literature on these subjects. This test method does offer a referee technique (the standard gold foil) to aid the experimenter when they are in doubt of their ability to perform the radiometric technique with sufficient accuracy.4.2 The standard comparison technique uses a set of foils that are as nearly identical as possible in shape and mass. The foils are fabricated from any material that activates by an (n, γ) reaction, preferably having a cross section approximately inversely proportional to neutron speed in the thermal energy range. Some of the foils are irradiated in a known neutron field (at NIST) or other standards laboratory). The foils are counted in a fixed geometry on a stable radiation-detecting instrument. The neutron-induced reaction rate of the foils is computed from the counting data, and the ratio of the known neutron fluence rate to the computed reaction rate is determined. For any given foil, neutron energy spectrum, and counting set-up, this ratio is a constant. Other foils from the identical set can now be exposed to an unknown neutron field. The magnitude of the fluence rate in the unknown field can be obtained by comparing the reaction rates as determined from the counting data from the unknown and reference field, with proper corrections to account for spectral differences between the two fields (see Section 5). One important feature of this technique is that it eliminates the need for knowing the detector efficiency.4.3 This test method follows the Stoughton and Halperin convention for reporting thermal neutron fluence. Other conventions are the Wescott convention (followed in Test Method E481) and the Hogdahl convention. Practice E261 explains the three conventions and gives conversion formulae relating values determined by the different conventions. Reference (1)3 discusses the three thermal-neutron conventions in detail.1.1 The purpose of this test method is to define a general procedure for determining an unknown thermal-neutron fluence rate by neutron activation techniques. It is not practicable to describe completely a technique applicable to the large number of experimental situations that require the measurement of a thermal-neutron fluence rate. Therefore, this method is presented so that the user may adapt to their particular situation the fundamental procedures of the following techniques.1.1.1 Radiometric counting technique using pure cobalt, pure gold, pure indium, cobalt-aluminum, alloy, gold-aluminum alloy, or indium-aluminum alloy.1.1.2 Standard comparison technique using pure gold, or gold-aluminum alloy, and1.1.3 Secondary standard comparison techniques using pure indium, indium-aluminum alloy, pure dysprosium, or dysprosium-aluminum alloy.1.2 The techniques presented are limited to measurements at room temperatures. However, special problems when making thermal-neutron fluence rate measurements in high-temperature environments are discussed in 9.2. For those circumstances where the use of cadmium as a thermal shield is undesirable because of potential spectrum perturbations or of temperatures above the melting point of cadmium, the method described in Test Method E481 can be used in some cases. Alternatively, gadolinium filters may be used instead of cadmium. For high temperature applications in which aluminum alloys are unsuitable, other alloys such as cobalt-nickel or cobalt-vanadium have been used.1.3 This test method may be used to determine the equivalent 2200 m/s fluence rate. The accurate determination of the actual thermal neutron fluence rate requires knowledge of the neutron temperature, and determination of the neutron temperature is not within the scope of the standard.1.4 The techniques presented are suitable only for neutron fields having a significant thermal neutron component, in which moderating materials are present, and for which the average scattering cross section is large compared to the average absorption cross section in the thermal neutron energy range.1.5 Table 1 indicates the useful neutron-fluence ranges for each detector material.TABLE 1 Useful Neutron Fluence Ranges of Foil MaterialFoil Material Form ≈ Useful Range (neutrons/cm 2)Indium pure or alloyed with aluminum 103 to 1012Gold pure or alloyed with aluminum 107 to 1014Dysprosium pure or alloyed with aluminum 103 to 1010Cobalt pure or alloyed with aluminum 1014 to 10201.6 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 Refer to Guide E844 for guidance on the selection, irradiation, and quality control of neutron dosimeters. 5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors. 5.3 Pure iron in the form of foil or wire is readily available and easily handled. 5.4 Fig. 1 shows a plot of cross section as a function of neutron energy for the fast-neutron reaction 54Fe(n,p)54Mn (1).3 This figure is for illustrative purposes only to indicate the range of response of the 54Fe(n,p)54Mn reaction. Refer to Guide E1018 for recommended tabulated dosimetry cross sections. FIG. 1 54Fe(n,p)54Mn Cross Section 5.5 54Mn has a half-life of 312.19 (3) days4 (2) and emits a gamma ray with an energy of 834.855 (3) keV (2). 5.6 Interfering activities generated by neutron activation arising from thermal or fast neutron interactions are 2.57878 (46)-h 56Mn, 44.494 (12) days 59Fe, and 5.2711 (8) years 60Co (2,3). (Consult the latest version of Ref (2) for more precise values currently accepted for the half-lives.) Interference from 56Mn can be eliminated by waiting 48 h before counting. Although chemical separation of 54Mn from the irradiated iron is the most effective method for eliminating 59Fe and 60Co, direct counting of iron for 54Mn is possible using high-resolution detector systems or unfolding or stripping techniques, especially if the dosimeter was covered with cadmium or boron during irradiation. Altering the isotopic composition of the iron dosimeter is another useful technique for eliminating interference from extraneous activities when direct sample counting is to be employed. 5.7 The vapor pressures of manganese and iron are such that manganese diffusion losses from iron can become significant at temperatures above about 700°C. Therefore, precautions must be taken to avoid the diffusion loss of 54Mn from iron dosimeters at high temperature. Encapsulating the iron dosimeter in quartz or vanadium will contain the manganese at temperatures up to about 900°C. 5.8 Sections 6, 7 and 8 that follow were specifically written to describe the method of chemical separation and subsequent counting of the 54Mn activity. When one elects to count the iron dosimeters directly, those portions of Sections 6, 7 and 8 that pertain to radiochemical separation should be disregarded. Note 1: The following portions of this test method apply also to direct sample-counting methods: 6.1 – 6.3, 7.4, 7.9, 7.10, 8.1 – 8.5, 8.18, 8.19, and 9 – 12. 1.1 This test method describes procedures for measuring reaction rates by the activation reaction 54Fe(n,p)54Mn. 1.2 This activation reaction is useful for measuring neutrons with energies above approximately 2.2 MeV and for irradiation times up to about three years, provided that the analysis methods described in Practice E261 are followed. If dosimeters are analyzed after irradiation periods longer than three years, the information inferred about the fluence during irradiation periods more than three years before the end of the irradiation should not be relied upon without supporting data from dosimeters withdrawn earlier. 1.3 With suitable techniques, fission-neutron fluence rates above 108 cm−2·s−1 can be determined. However, in the presence of a high thermal-neutron fluence rate (for example, >2 × 1014 cm−2·s −1) 54Mn depletion should be investigated. 1.4 Detailed procedures describing the use of other fast-neutron detectors are referenced in Practice E261. 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 Refer to Guide E844 for the selection, irradiation, and quality control of neutron dosimeters. 5.2 Refer to Practice E261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors. 5.3 Pure nickel in the form of foil or wire is readily available, and easily handled. 5.4 58Co has a half-life of 70.85 (3) days (Refs (1) and (2))3 and emits a gamma ray with an energy of 810.7602 (20) keV (Refs (2) and (3)). 5.5 Competing activities 65Ni(2.5172 h) and 57Ni(35.9 (3) h (Ref (2)) are formed by the reactions 64Ni(n,γ) 65Ni, and 58Ni(n,2n)57Ni, respectively. 5.6 A second 9.04 h isomer, 58mCo, is formed that decays to 70.85-day 58Co. Loss of 58Co and 58mCo by thermal-neutron burnout will occur in environments (Refs (4) and (5) having thermal fluence rates of 3 × 1012 cm−2·s −1 and above. Burnout correction factors, R, are plotted as a function of time for several thermal fluxes in Fig. 1. Tabulated values for a continuous irradiation time are provided in Hogg, et al. (Ref (5)) 5.7 Fig. 2 shows a plot of cross section (Ref (6)) versus energy for the fast-neutron reaction 58Ni(n,p) 58Co. This figure is for illustrative purposes only to indicate the range of response of the 58Ni(n,p) reaction. Refer to Guide E1018 for descriptions of recommended tabulated dosimetry cross sections. FIG. 2 58Ni(n,p)58Co Cross Section Note 1: The data is taken from the Evaluated Nuclear Data File, ENDF/B-VI, rather than the later ENDF/B-VII. This is in accordance with E1018, section 6.1, since the later ENDF/B-VII data files do not include covariance information. For more details see Section H of Ref (7). 1.1 This test method covers procedures for measuring reaction rates by the activation reaction 58Ni(n,p)58Co. FIG. 1 R Correction Values as a Function of Irradiation Time and Neutron Flux Note 1: The burnup corrections were computed using effective burn-up cross sections of 1650 b for  58Co(n,γ) and 1.4E5 b for  58mCo(n,γ). 1.2 This activation reaction is useful for measuring neutrons with energies above approximately 2.1 MeV and for irradiation times up to about 200 days in the absence of high thermal neutron fluence rates, provided that the analysis methods described in Practice E261 are followed. If dosimeters are analyzed after irradiation periods longer than 200 days, the information inferred about the fluence during irradiation periods more than 200 days before the end of the irradiation should not be relied upon without supporting data from dosimeters withdrawn earlier. 1.3 With suitable techniques fission-neutron fluence rates densities above 107 cm−2·s −1 can be determined. 1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E261. 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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