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AbstractThe normal butane thermophysical property tables are for use in the calculation of the pressure-volume-temperature (PVT), thermodynamic, and transport properties of normal butane for process design and operations. The preparation of the tables and supporting work was done by the National Institute of Standards and Technology (NIST) under the sponsorship of the Gas Research Institute, the American Gas Association, and the Standard Reference Data Program of NIST. These thermophysical property tables are: thermophysical properties of coexisting gaseous and liquid normal butane and thermophysical properties of normal butane.1.1 The thermophysical property tables for normal butane are for use in the calculation of the pressure-volume-temperature (PVT), thermodynamic, and transport properties of normal butane for process design and operations. Two tables provide properties at the conditions of liquid-vapor equilibrium (saturation properties), one for liquid and one for vapor, at temperatures between 135 K and the critical point, 425.13 K. A third table provides properties at selected T, p points for the equilibrium phase at temperatures between 140 K and 570 K at pressures to 20 MPa. The tables were developed using the National Institute of Standards and Technology Standard Reference Database product REFPROP, version 10.0.1.2 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 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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1. Scope 1.1 General This Standard covers once-through high efficiency air-cleaning assemblies for maintaining radioactive particulate and radioiodine releases below licenced limits in nuclear power plants. The Standard identifies and establishes mi

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3.1 This test method provides an analysis in weight percent of the normal-propyl bromide concentration of virgin, formulated, or reclaimed normal-propyl bromide: compounds that co-elute with normal-propyl bromide or normal-heptane (internal standard) may interfere with this test method.1.1 This test method provides a basis for the determination of the normal-propyl bromide (weight %) in the presence of stabilizers and impurities, in virgin or reclaimed normal-propyl bromide (nPB). The application range is from 50 wt % to 100 wt %.1.2 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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AbstractThese test methods cover determination of the total normal emittance of surfaces by means of portable, inspection-meter instruments. At least two different types of instruments are commercially available for performing this measurement. Test Method A uses an instrument which measures radiant energy reflected from the specimen and Test Method B utilizes an instrument which measures radiant energy emitted from the specimen. Both test methods are limited in accuracy by the degree to which the emittance properties of calibrating standards are known and by the angular emittance characteristics of the surfaces being measure. Test Method A is normally subject to a small error caused by the difference in wavelength distributions between the radiant energy emitted by the two cavities at different temperatures, and that emitted by a blackbody at the specimen temperature. Test Method B also has nongray errors since the detector is not at absolute zero temperature. Test Method A is subject to small errors that may be introduced if the orientation of the sensing component is changed between calibration and specimen measurements. This type of error results from minor changes in alignment of the optical system. Test Method A is subject to error when curved specular surfaces of less than about a certain radius are measured. These errors can be minimized by using calibrating standards that have the same radius of curvature as the test surface. Test Method A can measure reflectance on specimens that are either opaque or semi-transparent in the wavelength region of interest. However, if emittance is to be derived from the reflectance data on a semi-transparent specimen, a correction must be made for transmittance losses. Test Method B is subject to several possible significant errors. These may be due to variation of the test surface temperature during measurements, differences in temperature between the calibrating standards and the test surfaces, changes in orientation of the sensing component between calibration and measurement, errors due to irradiation of the specimen with thermal radiation by the sensing component, and errors due to specimen curvature. Test Method B is limited to emittance measurements on specimens that are opaque to infrared radiation in the wavelength region of interest. 1.1 These test methods cover determination of the total normal emittance (Note 1) of surfaces by means of portable, as well as desktop, inspection-meter instruments. Note 1: Total normal emittance (εN) is defined as the ratio of the normal radiance of a specimen to that of a blackbody radiator at the same temperature. The equation relating εN to wavelength and spectral normal emittance [εN(λ)] is where: L b(λ, T)   =   Planck's blackbody radiation function = c1λ−5(ec2/λT − 1)−1, c1   =   3.7415 × 10−16W·m 2, c2   =   1.4388 × 10−2 m·K, T   =   absolute temperature, K, λ   =   wavelength, m,   =   σT4, and σ   =   Stefan-Boltzmann constant = 5.66961 × 10 −8 W·m−2·K−4 1.2 These test methods are intended for measurements on large surfaces, or small samples, or both, when rapid measurements must be made and where a nondestructive test is desired. They are particularly useful for production control tests. 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 The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance, or corrections must be made for the specified conditions.5.1.1 The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few kelvins.5.1.2 The optical path length in the two beams must be equal, or, preferably, the instrument should operate in a nonabsorbing atmosphere, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual-beam instruments becomes very critical.NOTE 4: Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrophotometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %.5.1.3 Front-surface mirror optics must be used throughout, except for the prism in prism monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings: MgF2 may be used to stabilize mirror surfaces for extended periods of time. The optical characteristics of these coatings are critical, but can be relaxed if all optical paths are fixed during measurements or the incident angles are not changed between modes of operation (during 0 % line, 100 % line, and sample measurements). It is recommended that all optical elements be adequately filled with energy.5.1.4 The source and field apertures of the two beams must be equal in order to ensure that radiant flux in the two beams compared by the apparatus will pertain to equal areas of the sources and equal solid angles of emission. In some cases it may be desirable to define the solid angle of the source and sample when comparing alternative measurement techniques.5.1.5 The response of the detector-amplifier system must vary linearly with the incident radiant flux, or must be calibrated for linearity, and corrections made for observed deviations from linearity.1.1 This test method describes an accurate technique for measuring the normal spectral emittance of electrically nonconducting materials in the temperature range from 1000 to 1800 K, and at wavelengths from 1 to 35 μm. It is particularly suitable for measuring the normal spectral emittance of materials such as ceramic oxides, which have relatively low thermal conductivity and are translucent to appreciable depths (several millimetres) below the surface, but which become essentially opaque at thicknesses of 10 mm or less.1.2 This test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is particularly suitable for research laboratories, where the highest precision and accuracy are desired, and is not recommended for routine production or acceptance testing. Because of its high accuracy, this test method may be used as a reference method to be applied to production and acceptance testing in case of dispute.1.3 This test method requires the use of a specific specimen size and configuration, and a specific heating and viewing technique. The design details of the critical specimen furnace are presented in Ref (1),2 and the use of a furnace of this design is necessary to comply with this test method. The transfer optics and spectrophotometer are discussed in general terms.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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