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定价： 156元 / 折扣价： 133 元 加购物车

5.1 Asphalt is a material used in the construction of roads and as a roofing material and sealant.5.2 This test method provides a means of evaluating exposure to asphalt fume in the working environment at the presently recommended exposure guidelines (for example, Threshold Limit Values and Biological Exposure Indices, ACGIH).75.3 This procedure has been adapted from NIOSH Method 5023 (withdrawn prior to 4th edition (1994) and replaced in 1998 with NIOSH Method 5042) and OSHA Method 58 to reduce the level of background contamination providing better reproducibility.1.1 This test method covers the determination of asphalt fume particulate matter (as benzene soluble fraction) and total particulate matter weight in workplace atmospheres using a polytetrafluoroethylene (PTFE) filter methodology.1.2 This procedure has been adapted from NIOSH Method 5023 (withdrawn prior to 4th edition (1994) and replaced in 1998 with NIOSH Method 5042) and OSHA Method 58. This adaptation was made to reduce the level of background contamination providing better reproducibility.1.3 This procedure is compatible with high flow rate personal sampling equipment–0.5 to 2.0 L/min. It can be used for personal or area monitoring.1.4 The sampling method develops a time-weighted average (TWA) sample and can be used to determine short-term exposure limit (STEL).1.5 The applicable concentration range for the TWA sample is from 0.2 to 2.0 mg/m3.NOTE 1: A study has suggested candidate solvents for benzene replacement.2 A less toxic solvent for this analysis would be more appropriate, although the substitution with a solvent other than benzene needs further validations with field data.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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. For more specific precautionary statements, see Section 9.1.8 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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 In 2014, the U.S. EPA published the final rules adding renewable fuel pathways under the RFS Program. The rules qualified kernel fiber as a cellulosic feedstock meeting the 60 % greenhouse gas (GHG) reduction and qualifies for the generation of D3 RINs. These rules allow for two approaches for kernel fiber conversion (CFR 40, Part 80 and EPA-HQ-OAR-2012-0401; FRL-9910-40-OAR):4.1.1 Producers of cellulosic fuels derived from conversion of feedstocks that are predominantly cellulosic, where “predominantly cellulosic” is defined as feedstock that has an average adjusted cellulosic content of 75 %, measured on a dry mass basis; furthermore, this ‘‘adjusted cellulosic content’’ is the percent of organic (non-ash) material that is cellulose, hemicellulose, or lignin (CFR 40, Part 80 and EPA-HQ-OAR-2012-0401; FRL-9910-40-OAR).4.1.2 Producers of cellulosic fuels derived from the simultaneous conversion of feedstocks that are predominantly cellulosic and feedstocks that are not predominantly cellulosic (CFR 40, Part 80 and EPA-HQ-OAR-2012-0401; FRL-9910-40-OAR).4.2 Producers that wish to gain approval to the pathway that claims simultaneous conversion of feedstocks that are predominantly cellulosic and feedstocks that are not predominantly cellulosic are required to quantify the amount of renewable fuel that is derived specifically from cellulosic content and from starch. To accomplish this, the producer needs to quantify the amount of cellulosic content and starch present before the conversion process begins and after the conversion process is complete. These measurements of cellulosic content and starch content before and after conversion are used to calculate a converted fraction of each, which is then used to ratio the renewable fuel produced accordingly and assign those respective gallons the D6 or D3 RIN code (CFR 40, Part 80 and EPA-HQ-OAR-2012-0401; FRL-9910-40-OAR).1.1 This practice provides criteria for the sampling, testing, and calculation methodologies used for the quantification of the converted fraction of starch and cellulosic content. Furthermore, this practice covers procedures for the management of the standard error associated with the sampling and testing of before conversion and after conversion samples from a fuel ethanol production facility.1.1.1 This practice can be used to determine the volume of renewable fuel produced from the simultaneous conversion of starch and cellulosic material eligible for generating D3 RINs under the United States (U.S.) Renewable Fuel Standard (RFS).1.2 This practice covers the collection and testing of heterogeneous material, including, but not limited to: corn, sorghum, wheat, mash, beer, whole stillage, dried distillers grains with solubles (DDGS), and dried distillers grains.1.3 This practice is intended to be used in renewable fuel production facilities designed to produce renewable alcohols. Use of this practice in any other type of process has not been reviewed.1.4 This practice can be utilized using either manual or automatic sampling techniques, so long as the criteria of this practice are followed.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 In Case 1, the sample is selected from a process or a very large population of interest. The population is essentially unlimited, and each item either has or has not the defined attribute. The population (process) has an unknown fraction of items p (long run average process non-conforming) having the attribute. The sample is a group of n discrete items selected at random from the process or population under consideration, and the attribute is not exhibited in the sample. The objective is to determine an upper confidence bound, pu, for the unknown fraction p whereby one can claim that p ≤ pu with some confidence coefficient (probability) C. The binomial distribution is the sampling distribution in this case.4.2 In Case 2, a sample of n items is selected at random from a finite lot of N items. Like Case 1, each item either has or has not the defined attribute, and the population has an unknown number, D, of items having the attribute. The sample does not exhibit the attribute. The objective is to determine an upper confidence bound, Du, for the unknown number D, whereby one can claim that D ≤ Du with some confidence coefficient (probability) C. The hypergeometric distribution is the sampling distribution in this case.4.3 In Case 3, there is a process, but the output is a continuum, such as area (for example, a roll of paper or other material, a field of crop), volume (for example, a volume of liquid or gas), or time (for example, hours, days, quarterly, etc.) The sample size is defined as that portion of the “continuum” sampled, and the defined attribute may occur any number of times over the sampled portion. There is an unknown average rate of occurrence, λ, for the defined attribute over the sampled interval of the continuum that is of interest. The sample does not exhibit the attribute. For a roll of paper, this might be blemishes per 100 ft2; for a volume of liquid, microbes per cubic litre; for a field of crop, spores per acre; for a time interval, calls per hour, customers per day or accidents per quarter. The rate, λ, is proportional to the size of the interval of interest. Thus, if λ = 12 blemishes per 100 ft2 of paper, this is equivalent to 1.2 blemishes per 10 ft2 or 30 blemishes per 250 ft2. It is important to keep in mind the size of the interval in the analysis and interpretation. The objective is to determine an upper confidence bound, λu, for the unknown occurrence rate λ, whereby one can claim that λ ≤ λu with some confidence coefficient (probability) C. The Poisson distribution is the sampling distribution in this case.4.4 A variation on Case 3 is the situation where the sampled “interval” is really a group of discrete items, and the defined attribute may occur any number of times within an item. This might be the case where the continuum is a process producing discrete items such as metal parts, and the attribute is defined as a scratch. Any number of scratches could occur on any single item. In such a case, the occurrence rate, λ, might be defined as scratches per 1000 parts or some similar metric.4.5 In each case, a sample of items or a portion of a continuum is examined for the presence of a defined attribute, and the attribute is not observed (that is, a zero response). The objective is to determine an upper confidence bound for either an unknown proportion, p (Case 1), an unknown quantity, D (Case 2), or an unknown rate of occurrence, λ (Case 3). In this practice, confidence means the probability that the unknown parameter is not more than the upper bound. More generally, these methods determine a relationship among sample size, confidence and the upper confidence bound. They can be used to determine the sample size required to demonstrate a specific p, D, or λ with some degree of confidence. They can also be used to determine the degree of confidence achieved in demonstrating a specified p, D, or λ.4.6 In this practice, allowance is made for misclassification error but only when misclassification rates are well understood or known, and can be approximated numerically.4.7 It is possible to impose the language of classical acceptance sampling theory on this method. Terms such as lot tolerance percent defective, acceptable quality level, and consumer quality level are not used in this practice. For more information on these terms, see Practice E1994.AbstractThis practice presents methodology for the setting of an upper confidence bound regarding an unknown fraction or quantity non-conforming, or a rate of occurrence for nonconformities, in cases where the method of attributes is used and there is a zero response in a sample. Three cases are considered. In Case 1, the sample is selected from a process or a very large population of interest. In Case 2, a sample of n items is selected at random from a finite lot of N items. In Case 3, there is a process, but the output is a continuum, such as area (for example, a roll of paper or other material, a field of crop), volume (for example, a volume of liquid or gas), or time (for example, hours, days, quarterly, etc.) The sample size is defined as that portion of the �continuum� sampled, and the defined attribute may occur any number of times over the sampled portion.1.1 This practice presents methodology for the setting of an upper confidence bound regarding a unknown fraction or quantity non-conforming, or a rate of occurrence for nonconformities, in cases where the method of attributes is used and there is a zero response in a sample. Three cases are considered.1.1.1 The sample is selected from a process or a very large population of discrete items, and the number of non-conforming items in the sample is zero.1.1.2 A sample of items is selected at random from a finite lot of discrete items, and the number of non-conforming items in the sample is zero.1.1.3 The sample is a portion of a continuum (time, space, volume, area, etc.) and the number of non-conformities in the sample is zero.1.2 Allowance is made for misclassification error in this practice, but only when misclassification rates are well understood or known and can be approximated numerically.1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 Au nano-objects in various shapes (that is, rods, particles) are increasingly used for a wide variety of applications. Medical applications of AuNPs, such as targeted drug delivery, tumor detection, and treatment are becoming more common (5). AuNPs have unique optical properties related to their size and their surface can be readily functionalized. Though Au is recognized to be inert and biocompatible in its bulk form, the behavior of Au nano-objects in biological systems and the environment must be tested to ensure their inertness and safety (6). It is important to know whether prepared and stored suspensions of AuNPs contain Au in its bound state (commonly Au (0) and particle adsorbed species) or ionized state (commonly, Au (I) or Au (III)) to attribute the biological response to the appropriate species. Krug, et al., concluded that the significance of toxicity studies is considerably reduced in those cases where the material properties of the nanomaterial suspensions were not characterized prior to and during the study (7). Furthermore, the analyte mass fraction of particle bound species is used with knowledge of particle size to compute particle number concentration.1.1 This test method describes the use of inductively coupled plasma optical emission spectrometry (ICP-OES; also includes ICP-AES, where AES is atomic emission spectrometry) or inductively coupled plasma mass spectrometry (ICP-MS) for the determination of the mass fraction of particle bound gold (Au) in colloidal Au suspensions. Particle bound Au is defined as the mass of Au associated with the nanoparticle (NP) fraction and strongly adsorbed to the particle surface. Unbound Au is the fraction of Au in the native suspension not associated with the Au nanoparticle fraction that is, the dissolved Au existing in solution as a complex or free ion. The mass fraction of particle bound Au is determined by subtracting the mass fraction of unbound Au measured in acidified subsamples of the particle-free supernatant from the total Au mass fraction measured in acid-digested subsamples of the colloidal Au suspension. The particle-free supernatant is obtained after centrifugation of the colloidal Au suspension. This standard prescribes the use of an appropriate internal standard and calibration using either external standardization or single-point standard additions.1.2 Colloidal gold suspensions with AuNP diameters ranging from 1 nm to 100 nm can be determined with this method.1.3 The standard is not limited to particles with a uniform Au composition and may be applicable to a core-shell particle with a Au shell treatment.1.4 This standard is specific to Au. The method may be applicable to other elements measurable by ICP-OES or ICP-MS but is limited to nanoparticles that are not reactive in aqueous suspension.1.5 No detailed instructions for operating instrumentation are provided because of differences among various makes and models. Instead, the analyst shall follow the instructions provided by the manufacturer of their particular ICP-OES, ICP-MS or centrifuge instrument, especially with regard to optimization of the instrument settings.1.6 The values stated in SI units are to be regarded as standard. No other units of measurements are included in this standard.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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3.1 These test methods are for the chemical analysis of mass fraction of carbon, nitrogen, and oxygen in silicon nitride powder. They are used in research, development, production, acceptance, and quality control of silicon nitride powders used to produce ceramic components with silicon nitride content.3.2 It is assumed that all who use these test methods will be trained analysts capable of performing common laboratory procedures skillfully and safely. It is expected that work will be performed in a properly equipped laboratory.1.1 These test methods cover the determination of mass fraction % of carbon, nitrogen, and oxygen in silicon nitride powder having chemical compositions within the following limits:Element Mass Fraction % RangeCarbon 0.05 to 5.0Nitrogen 30 to 45Oxygen 0.1 to 1.51.2 Two test methods appear in this standard.1.2.1 Total Carbon by the Direct Combustion-Infrared Measurement Method.1.2.2 Nitrogen by the Inert Gas Fusion-Thermal Conductivity Measurement Method and Oxygen by the Inert Gas Fusion-Infrared Measurement Method.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. Specific hazard statements are given in Section 6.1.4 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 based upon the stereological principle that a grid with a number of regularly arrayed points, when systematically placed over an image of a two-dimensional section through the microstructure, can provide, after a representative number of placements on different fields, an unbiased statistical estimation of the volume fraction of an identifiable constituent or phase (1, 2, 3).35.2 This test method has been described (4) as being superior to other manual methods with regard to effort, bias, and simplicity.5.3 Any number of clearly distinguishable constituents or phases within a microstructure (or macrostructure) can be counted using the method. Thus, the method can be applied to any type of solid material from which adequate two-dimensional sections can be prepared and observed.5.4 A condensed step-by-step guide for using the method is given in Annex A1.1.1 This test method describes a systematic manual point counting procedure for statistically estimating the volume fraction of an identifiable constituent or phase from sections through the microstructure by means of a point grid.1.2 The use of automatic image analysis to determine the volume fraction of constituents is described in Practice E1245.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

3.1 This test method is used for determining the amount of a temperature-specific volatile distillate fraction in cold mix asphalt 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 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 the determination, by direct measurement, of the ambient to 260 °C [500 °F] volatile distillate fraction of cold mix asphalt mixtures.1.2 A precision and bias statement for this test method has not been developed since this test method is used for research purposes or information only. Therefore this test method should not be used for acceptance or rejection of a material for purchasing purposes.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.4 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.1.5 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 The enrichment meter principle provides a nondestructive measurement of the 235U fraction of uranium-bearing items. Sampling is not required and no waste is generated, minimizing exposure to hazardous materials and resulting in reduced sampling error. 5.2 This method relies on a fixed and controlled geometry. The uranium-bearing materials in the measured items and calibration reference materials used for calibration must fill the detector field of view. 5.3 Use of a low resolution detector (for example, NaI detector) to measure uranium with 235U fraction approximately 10 % which is contained in a thin-walled container can provide a rapid (typically 100 s), easily portable measurement system with precision of 0.6 % and bias of less than 1 %. 5.4 Use of a high resolution detector (for example, high-purity germanium) can provide measurement with a precision better than 0.2 % and a bias less than 1 % within a 300-s measurement time when measuring uranium with 235U fraction in the range of 0.711 % or above which is contained in thin-walled containers. 5.5 In order to obtain optimum results using this method, the chemical composition of the item must be well known, the container wall must permit transmission of the 185.7 keV gamma-ray, and the uranium-bearing material within the item must be infinitely thick with respect to the 185.7 keV gamma-ray. All items must be in identical containers or must have a known container wall thickness and composition. 5.6 Items to be measured must be homogeneous with respect to both 235U fraction and chemical composition. 5.7 When measuring items, using low-resolution detectors, in thin-walled containers that have not reached secular equilibrium (more than about 120 days after processing), either the method should not be used, additional corrections should be made to account for the age of the uranium, or high-resolution measurements should be performed. 5.8 The method is often used as a enrichment verification technique. 1.1 This test method covers the quantitative determination of the fraction of 235U in uranium using measurement of the 185.7 keV gamma-ray produced during the decay of 235U. 1.2 This test method is applicable to items containing homogeneous uranium-bearing materials of known chemical composition in which the compound is considered infinitely thick with respect to 185.7 keV gamma-rays. 1.3 This test method can be used for the entire range of 235U fraction as a weight percent, from depleted (0.2 % 235U) to highly enriched (97.5 % 235U). 1.4 Measurement of items that have not reached secular equilibrium between 238U and 234Th may not produce the stated bias when low-resolution detectors are used with the computational method listed in Annex A2. 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 may involve hazardous materials, operations, and equipment. 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 The tread of a tire, the annular band that contacts the pavement, normally contains geometric tread pattern elements that are defined by grooves or voids. These are employed to confer appropriate traction properties to the tire, mainly on wet or snow-covered roads.5.2 One characteristic feature of tire tread patterns that is important for both traction and tire wear behavior is the percent or “fractional” groove area. The groove-area fraction is calculated with respect to the total or gross contact area.1.1 This practice covers a technique for measuring the groove or void area of a tire tread pattern. The void area is measured on the inked impression of a tire tread statically loaded against heavyweight paper on a load platen.1.2 This procedure is intended to serve as a reference practice for measuring groove or tread pattern void areas in a tire-footprint impression. This technique is usable by any laboratory without special equipment although more sophisticated procedures are also commonly employed, such as optical or video camera processes.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.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车