定价： 156元 / 折扣价： 133 元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

5.1 Solar reflectance and thermal emittance are important factors affecting surface and near-surface ambient air temperature. Surfaces with low solar reflectance, absorb a high fraction of the incoming solar energy. A fraction of this absorbed energy is conducted into ground and buildings, a fraction is convected to air (leading to higher air temperatures), and a fraction is radiated to the sky. For equivalent conditions, the lower the emissivity of a surface the higher its steady-state temperature. Surfaces with low emissivity cannot effectively radiate to the sky and, therefore, get hot. Determination of solar reflectance and thermal emittance, and subsequent calculation of the relative temperature of the surfaces with respect to black and white reference temperature (defined as Solar Reflectance Index, SRI), may help designers and consumers to choose the proper materials to make their buildings and communities energy efficient. The method described here gives the SRI of surfaces based on measured solar reflectances and thermal emissivities of the surfaces.1.1 This practice covers the calculation of the Solar Reflectance Index (SRI) of horizontal and low-sloped opaque surfaces at standard conditions. The method is intended to calculate SRI for surfaces with emissivity greater than 0.1.1.2 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 describes the means of determining the LRV of a tile specimen. Certain building codes require the use of materials rated by LRV. Application of this test method provides the means for rating ceramic tile. LRVs reported for ceramic tile should include reference to the observer and illuminant for which the rating is valid. 5.2 LRV is a property dependent on the overall color of a tile specimen. Control of LRV is achieved through control of color and adherence to color specifications will govern the acceptability of a product with respect to LRV. Therefore, a product cannot be judged as having an unacceptable LRV unless the color of the product is found to be unacceptable. 5.3 Mixtures of several tile products are commonly installed on a surface, requiring a means to calculate LRV for a product mix. The rating obtained for an individual tile product can be used to calculate the LRV for a product mix using the following equation: where: n   =   number of products included in the mix, p1 to n   =   the proportion of the surface area taken up by each product; the sum of p1 to pn must equal one), and LRV1 to n   =   the LRV for each product used. For example, a mixture of two products is used on a surface. Two thirds of the surface area is covered by product A with a LRV of 75 %, and one third of the surface is covered by product B with an LRV of 60 % (see Fig. 2). Using the equation, the product mix is found to have an LRV of 70 %. FIG. 2 Example of Product Mix Used on Surface 5.4 The test method described herein provides instrumental means as the basis for judging color difference. Magnitude of color difference between pairs of ceramic tile can be determined and expressed in numerical terms. 5.5 Based on interlaboratory investigation,3 color difference ΔE of plain-colored tile, if determined in accordance with this test method, should give excellent reproducibility with a standard deviation of not more than σ = ±0.15 units. LRV should also give excellent reproducibility when used for solid colored tile based on the relationship between LRV and either the Y tristimulus or L value. However, LRV reproducibility for multicolored, speckled, or textured surface tile will be dependent upon the degree of variation of the tile specimen, and will require a different measurement procedure to minimize the impact of the variation. 5.6 The test method requires the use of multiple illuminants for the determination of color difference between solid-colored tiles. Evaluation under incandescent, fluorescent and daylight illuminant conditions ensure the color differences calculated between a test and reference specimen account for the possible occurrence of metamerism. 1.1 This test method covers the measurement of Light Reflectance Value (LRV) and visually small color difference between pieces of glazed or unglazed ceramic tile, using any spectrophotometer that meets the requirements specified in the test method. LRV and the magnitude and direction of the color difference are expressed numerically, with sufficient accuracy for use in product specification. 1.2 LRV may be measured for either solid-colored tile or tile having a multicolored, speckled, or textured surface. For tile that are not solid-colored, an average reading should be obtained from multiple measurements taken in a pattern representative of the overall sample as described in 9.2 of this test method. Small color difference between tiles should only be measured for solid-color tiles. Small color difference between tile that have a multicolored, speckled, or textured surface are not valid. 1.3 For solid colored tile, a comparison of the test specimen and reference specimen should be made under incandescent, fluorescent and daylight illuminant conditions. The use of multiple illuminants allows the color difference measurement to be made without the risk of wrongly accepting a match when the tiles being compared are metamers (see 3.1.4). 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are provided for information only and are not considered 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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Color measurement quantifies the coating color for glass and is often related to coating thickness and composition as well as tinting used in the substrate glass. The user of this document defines an acceptable range of color appropriate for the end use. Typical quality concerns for the reflected color measurement of coated glass products are an indication of consistency in the coating process and verification of lot-to-lot color consistency for end-user acceptance.4.2 If the reflected color of a glass product is consistent from lot-to-lot and within agreed supplier-buyer acceptance criteria, that product color is expected to be consistent and acceptable for end-use.1.1 This practice provides guidelines for the instrumental reflectance measurement of the color of flat, coated and uncoated glass. (See Terminology E284.)1.2 The practice specifically excludes fluorescent and iridescent samples.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： 515元 / 折扣价： 438 元 加购物车

5.1 All commercial reflectometers measure relative reflectance. The instrument reading is the reflectance factor, the ratio of the light reflected by a reference specimen to that reflected by a test specimen. That ratio is dependent on specific instrument parameters.5.2 National standardizing laboratories and some research laboratories measure reflectance on instruments calibrated from basic principles, thereby establishing a scale of absolute reflectance as described in CIE Publication No. 44 (2). These measurements are sufficiently difficult that they are usually left to laboratories that specialize in them.5.3 A standard that has been measured on an absolute scale could be used to transfer that scale to a reflectometer. While such procedures exist, the constraints placed on the mechanical properties restrict the suitability of some optical properties, especially those properties related to the geometric distribution of the reflected light. Thus, reflectance factor standards which are sufficiently rugged and able to be cleaned, depart considerably from the perfect diffuser in the geometric distribution of reflected radiance.5.4 The geometric distribution of reflected radiance from a pressed powder plaque is sufficiently diffuse to provide a dependable calibration of a directional-hemispherical reflectometer. Although pressed powder standards are subject to contamination and breakage, the directional-hemispherical reflectance factor of pressed powder standards can be sufficiently reproducible from specimen to specimen made from a given lot of powder, so as to allow one to assign absolute reflectance factor values to all the powder in a lot.5.5 This practice describes how to prepare white reflectance factor standards from a powder in a manner that allows a standardizing laboratory to assign the absolute scale of reflectance to the plaque.NOTE 1: The collar and receptacle should be securely held in place before pressing the powder.1.1 This practice covers procedures for preparing pressed powder transfer standards. These standards can be used in the near-ultraviolet, visible and near-infrared region of the electromagnetic spectrum. Procedures for calibrating the reflectance factor of materials on an absolute basis are contained in CIE Publication No. 44 (2). Pressed powder standards are used as transfer standards for such calibrations because they have a high reflectance factor that is nearly constant with wavelength, and because the geometric distribution of reflected flux resembles that from the perfect reflecting diffuser.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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Solar-energy transmittance and reflectance are important factors in the heat admission through fenestration, most commonly through glass or plastics. (See Appendix X3.) These methods provide a means of measuring these factors under fixed conditions of incidence and viewing. While the data may be of assistance to designers in the selection and specification of glazing materials, the solar-energy transmittance and reflectance are not sufficient to define the rate of heat transfer without information on other important factors. The methods have been found practical for both transparent and translucent materials as well as for those with transmittances reduced by highly reflective coatings. Method B is particularly suitable for the measurement of transmittance of inhomogeneous, patterned, or corrugated materials since the transmittance is averaged over a large area.1.1 These test methods cover the measurement of solar energy transmittance and reflectance (terrestrial) of materials in sheet form. Method A, using a spectrophotometer, is applicable for both transmittance and reflectance and is the referee method. Method B is applicable only for measurement of transmittance using a pyranometer in an enclosure and the sun as the energy source. Specimens for Method A are limited in size by the geometry of the spectrophotometer while Method B requires a specimen 0.61 m2 (2 ft2). For the materials studied by the drafting task group, both test methods give essentially equivalent results.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： 590元 / 折扣价： 502 元 加购物车

5.1 The solar reflectance of a building envelope surface affects surface temperature and near-surface ambient air temperature. Surfaces with low solar reflectance absorb a high fraction of the incoming solar energy. Sunlight absorbed by a roof or by other building envelope surfaces can be conducted into the building, increasing cooling load and decreasing heating load in a conditioned building, or raising indoor temperature in an unconditioned building. It can also warm the outside air by convection. Determination of solar reflectance can help designers and consumers choose appropriate materials for their buildings and communities.5.1.1 The solar reflectance of a new building envelope surface often changes within one to two years through deposition and retention of soot and dust; microbiological growth; exposure to sunlight, precipitation, and dew; and other processes of soiling and weathering. For example, light-colored “cool” envelope surfaces with high initial reflectance can experience substantial reflectance loss as they are covered with dark soiling agents. Current product rating programs require roofing manufacturers to report values of solar reflectance and thermal emittance measured after three years of natural exposure (2, 3). A rapid laboratory process for soiling and weathering that simulates the three-year-aged radiative properties of roof and other building envelope surface materials expedites the development, testing, and introduction to market of such products.5.2 Thermal emittance describes the efficiency with which a surface exchanges thermal radiation with its environment. High thermal emittance enhances the ability of a surface to stay cool in the sun. The thermal emittance of a bare metal surface is initially low, and often increases as it is soiled or oxidized (4). The thermal emittance of a typical non-metal surface is initially high, and remains high after soiling (5).5.3 This practice allows measurement of the solar reflectance and thermal emittance of a roofing specimen after the application of the simulated field exposure.5.4 This practice is intended to be referenced by another standard, such as ANSI/CRRC S100, that specifies practices for specimen selection and methods for radiative measurement.1.1 Practice D7897 applies to simulation of the effects of field exposure on the solar reflectance and thermal emittance of roof surface materials including but not limited to field-applied coatings, factory-applied coatings, single-ply membranes, modified bitumen products, shingles, tiles, and metal products. The solar reflectance and thermal emittance of roof surfacing materials can be changed by exposure to the outdoor environment. These changes are caused by three factors: deposition and retention of airborne pollutants, microbiological growth, and changes in physical or chemical properties. This practice applies to simulation of changes in solar reflectance and thermal emittance induced by deposition and retention of airborne pollutants and, to a limited extent, changes caused by microbiological growth.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 To overcome the inadequacies of conventional spectrophotometric measurement techniques when nonhomogeneous materials are measured, a large integrating sphere may be used.4,5 Since the beam employed in such spheres is large in comparison to the disparaties of the materials being tested, the nonisotropic nature of the specimen being measured is essentially averaged, or integrated out of the measurement, in a single experimental determination.5.2 Solar and photopic optical properties may be measured either with monofunctional spheres individually tailored for the measurement of either transmittance5 or reflectance, or may be measured with a single multifunctional sphere that is employed to measure both transmittance and reflectance.45.3 A multifunctional sphere is used for making total solar transmittance measurements in both a directional-hemispherical and a directional-directional mode. The solar absorptance can be evaluated in a single measurement as one minus the sum of the directional hemispherical reflectance and transmittance. When a sample at the center of the sphere is supported by its rim, the sum of the reflectance and transmittance can be measured as a function of the angle of incidence. The solar absorptance is then one minus the measured absorptance plus transmittance.1.1 This test method covers the measurement of the absolute total solar or photopic reflectance, transmittance, or absorptance of materials and surfaces. Although there are several applicable test methods employed for determining the optical properties of materials, they are generally useful only for flat, homogeneous, isotropic specimens. Materials that are patterned, textured, corrugated, or are of unusual size cannot be measured accurately using conventional spectrophotometric techniques, or require numerous measurements to obtain a relevant optical value. The purpose of this test method is to provide a means for making accurate optical property measurements of spatially nonuniform materials.1.2 This test method is applicable to large specimens of materials having both specular and diffuse optical properties. It is particularly suited to the measurement of the reflectance of opaque materials and the reflectance and transmittance of semitransparent materials including corrugated fiber-reinforced plastic, composite transparent and translucent samples, heavily textured surfaces, and nonhomogeneous materials such as woven wood, window blinds, draperies, etc.1.3 The values stated in SI units are to be regarded as the 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. (For specific safety hazards, see Note 1.)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： 515元 / 折扣价： 438 元 加购物车

5.1 Acoustical materials are often used as the entire ceiling of rooms and are therefore an important component of the lighting system. The luminous reflectance of all important components must be known in order to predict the level of illumination that will be obtained.5.2 The reflecting properties of a surface are measured relative to those of a standard reflector, the perfect reflecting diffuser, to provide a reflectance factor. The luminous reflectance factor is calculated for a standard illuminant, and a standard observer, for the standard hemispherical (integrating-sphere) geometry of illumination and viewing, in which all reflected radiation from an area of the surface is collected. In this way the reflecting properties of an acoustical material can be represented by a single number measured and calculated under standard conditions.5.3 Acoustical materials generally have a non-glossy white or near-white finish. The types of surface cover a wide range from smooth to deeply fissured. Measurement with integrating-sphere reflectometers has been satisfactory although multiple measurements may be required to sample the surface adequately. Instruments with other types of optical measuring systems may be used if it can be demonstrated that they provide equivalent results.5.4 The use of this test method for determining the luminous reflectance factor is required by Classification E1264.1.1 This test method covers the measurement of the luminous reflectance factor of acoustical materials for use in predicting the levels of room illumination.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 Most commercial reflectometers and spectrophotometers with reflectance capability measure relative reflectance. The instrument reading is the ratio of the measured radiation reflected from the reference specimen to the measured radiation reflected by the test specimen. That ratio is dependent on specific instrument parameters.5.2 National standardizing laboratories and some research laboratories measure reflectance on instruments calibrated from basic principles, thereby establishing a scale of absolute reflectance as described in CIE Publication No. 44 (5). These measurements are sufficiently difficult and of prohibitive cost that they are usually left to laboratories that specialize in them.5.3 A standard that has been measured on an absolute scale could be used to transfer that scale to a reflectometer. While such procedures exist, the constraints placed on the mechanical properties restrict the suitability of some of the optical properties, especially those properties related to the geometric distribution of reflected radiation. Thus, reflectance factor standards that are sufficiently rugged or cleanable to use as permanent transfer standards, with the exception of the sintered PTFE standards, depart considerably from the perfect diffuser in the geometric distribution of reflected radiation.5.4 The geometric distribution of reflected radiance from such standards is sufficiently diffuse that such a standard can provide a dependable calibration of a directional-hemispherical or certain directional-directional reflectometers. Although pressed powder standards are subject to contamination and breakage, the reflectance factor of pressed powder can be sufficiently reproducible from specimen to specimen from a given lot of powder to allow the assignment of absolute reflectance factor values to all of the powder in a lot.5.5 Sintered PTFE materials exhibit sufficient reproducibility from within the same specimen after resurfacing or cleaning the specimen to allow the assignment of absolute reflectance factor values.5.6 Preparation of packed powder reflectance standards is covered in Practice E259. This practice describes the spectral and physical properties of these materials and of the sintered PTFE materials.1.1 This practice covers procedures for the preparation and use of acceptable transfer standards for NIR spectrophotometers. Procedures for calibrating the reflectance factor of materials on an absolute basis are contained in CIE Publication No. 44 (9). Both the pressed powder samples and the sintered PTFE materials are used as transfer standards for such calibrations because they have very stable reflectance factors that are nearly constant with wavelength and because the distribution of flux resembles closely that from the perfect reflecting diffuser.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.

定价： 515元 / 折扣价： 438 元 加购物车

5.1 The mean reflectance of the vitrinite maceral in sedimentary rocks as determined by this test method is used as an indicator of thermal maturity, that is, the progressive geochemical alteration of dispersed organic material experienced during diagenesis, catagenesis, and metagenesis. In the case of hydrocarbon source rocks, three major categories of thermal maturity are defined by vitrinite reflectance: immature (Roran ≤ 0.5 %), mature (Roran ≈ 0.5 % to 1.35 %), and overmature (Roran ≥ 1.35 %) with respect to the generation of liquid hydrocarbons, although not all practitioners agree on these thermal boundaries (10). Thermal maturity as determined by the reflectance of vitrinite dispersed in sedimentary rocks is similar to the rank classification of coals as presented in Classification D388 and measured similarly to the reflectance of vitrinite in coal as presented in Test Method D2798. The mean reflectance of the vitrinite maceral in sedimentary rocks correlates with geochemically determined parameters of thermal maturity and can be used to characterize thermal maturation history, to calibrate burial history models, and to better understand the processes of hydrocarbon generation, migration, and accumulation in conventional and unconventional petroleum systems.1.1 This test method covers the microscopical determination of the reflectance measured in immersion oil of polished surfaces of vitrinite dispersed in sedimentary rocks. This test method can also be used to determine the reflectance of macerals other than vitrinite dispersed in sedimentary rocks.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 Heat buildup of polymeric building products due to absorption of energy from the sun may lead to distortion problems. Test Method Test Method D4803 was developed to predict a building product’s heat buildup (temperature rise). It compares the relative temperature changes of a pigmented PVC product and a PVC panel containing carbon black when exposed to an infrared heat lamp. Based on experimental results that determined the maximum temperature for this black panel under both solar exposure and in the laboratory test, a method for determining the exterior temperature rise and heat buildup for a test panel was developed. This test has shown to be useful and reliable but is time consuming and requires controlled conditions to minimize sources of variation.5.2 This test method uses a spectrophotometer to measure a specimen’s reflectance in the ultraviolet, visible, and near infrared region and uses the spectral power distribution of the heat lamp specified in Test Method D4803 to determine an intensity factor, which is an index of the relative spectral energy absorption by the specimen.5.2.1 The temperature rise that would occur under an Test Method D4803 test is proportional to this intensity factor. An equation has been derived from the correlation of the intensity factor and temperature rise data obtained from Test Method D4803 testing of samples with a wide range of color and lightness. A total of 99 samples were studied and represent samples with the lowest to highest temperature rise. Linear regression analysis yields a R2 correlation coefficient of 0.98.5.2.2 The procedure in Appendix X1 allows prediction of temperature rise that would result from testing of the same sample under Test Method D4803.5.2.3 As this procedure is a correlation to results obtained by Test Method D4803, it is a method that yields a relative temperature rise compared to black under certain defined severe conditions, but does not predict actual field application temperatures of the product. These product temperatures are influenced by incident angle of the sun, clouds, wind speed, insulation, installation behind glass, etc.5.3 The intensity factor itself is a dimensionless index of the relative energy absorption of the specimen, without conversion to a temperature rise. It can be used to compare the heat buildup characteristics of different colors, or different candidate formulations for the same color. It can also be used to categorize color into ranges of intensity factor, to be used as a basis for testing of full siding products for resistance to thermal distortion.1.1 This test method uses reflectance spectra from the ultraviolet, visible, and near infrared region to produce an index of the temperature rise of polymeric siding above ambient temperature that occurs due to absorption of the sun’s energy.1.2 The test method determines the intensity factor of a sample color. The intensity factor is a function of the sample’s reflectance spectra and the energy output of the heat lamp used in the test method Test Method D4803.1.3 Appendix X1 provides a method for using the intensity factor to determine the maximum temperature rise of a sample under severe solar exposure.1.3.1 A correlation between intensity factor and heat buildup (temperature rise) as predicted by Test Method D4803 exists.1.3.2 The heat buildup (temperature rise) for a polymeric building product specimen is determined from its reflectance spectra and the correlation’s regression equation.1.4 Units—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.

定价： 515元 / 折扣价： 438 元 加购物车

5.1 Solar-energy absorptance, reflectance, and transmittance are important in the performance of all solar energy systems ranging from passive building systems to central receiver power systems. This test method provides a means for determining these values under fixed conditions that represent an average that would be encountered during use of a system in the temperate zone.5.2 Solar-energy absorptance, reflectance, and transmittance are important for thermal control of spacecraft and the solar power of extraterrestrial systems. This test method also provides a means for determining these values for extraterrestrial conditions.5.3 This test method is designed to provide reproducible data appropriate for comparison of results among laboratories or at different times by the same laboratory and for comparison of data obtained on different materials.5.4 This test method has been found practical for smooth materials having both specular and diffuse optical properties. Materials that are textured, inhomogeneous, patterned, or corrugated require special consideration.5.4.1 Surface roughness may be introduced by physical or chemical processes, such as pressing, rolling, etching, or deposition of films or chemical layers on materials, resulting in textured surfaces.5.4.2 The magnitude of surface roughness with respect to the components of the spectrophotometer and attachments (light beam sizes, sphere apertures, sample holder configuration) can significantly affect the accuracy of measurements using this test method.5.4.3 Even if the repeatability, or precision of the measurement of textured materials is good, including repeated measurements at various locations within or orientations of the sample, the different characteristics of different spectrophotometers in different laboratories may result in significant differences in measurement results.5.4.4 In the context of 5.4.3, the term ‘significant’ means differences exceeding the calibration or measurement uncertainty, or both, established for the spectrophotometers involved, through measurement of or calibration with standard reference materials.5.4.5 The caveats of 5.4.3 and 5.4.4 apply as well to measurement of smooth inhomogeneous or diffusing materials, where incident light may propogate to the edge of the test material and be ‘lost’ with respect to the measurement.5.5 This test method describes measurements accomplished over wider spectral ranges than the Photopic response of the human eye. Measurements are typically made indoors using light sources other than natural sunlight, though it is possible to configure systems using natural sunlight as the illumination source, as in Practice E424. Practice E971 describes outdoor methods using natural sunlight over the spectral response range of the human eye.5.6 Light diffracted by gratings is typically significantly polarized. For polarizing samples, measurement data will be a function of the orientation of the sample. Polarization effects may be detected by measuring the sample with rotation at various angles about the normal to the samples.1.1 This test method covers the measurement of spectral absorptance, reflectance, and transmittance of materials using spectrophotometers equipped with integrating spheres.1.2 Methods of computing solar weighted properties from the measured spectral values are specified.1.3 This test method is applicable to materials having both specular and diffuse optical properties.1.4 This test method is applicable to material with applied optical coatings with special consideration for the impact on the textures of the material under test.1.5 Transmitting sheet materials that are inhomogeneous, textured, patterned, or corrugated require special considerations with respect to the applicability of this test method. Test Method E1084 may be more appropriate to determine the bulk optical properties of textured or inhomogeneous materials.1.6 For homogeneous materials this test method is preferred over Test Method E1084.1.7 This test method refers to applications using standard reference solar spectral distributions but may be applied using alternative selected spectra as long as the source and details of the solar spectral distribution and weighting are reported.1.8 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.1.9 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