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定价： 819元 / 折扣价： 697 元 加购物车

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定价： 156元 / 折扣价： 133 元 加购物车

定价： 481元 / 折扣价： 409 元

5.1 General—Hydrogen sulfide is nearly ubiquitous. It occurs naturally in volcanic gases, in sulfur springs and fumaroles, in decaying of plant and animal protein, and in intestines as a result of bacterial action. Hydrogen sulfide is a serious hazard to the health of workers employed in energy production from hydrocarbon or geothermal sources, in the production of fibers and sheets from viscose syrup, in the production of deuterium oxide (heavy water), in tanneries, sewers, sewage treatment and animal waste disposal, in work below ground, on fishing boats, and in chemical operations, including the gas and oil industry.5.2 In 29 CFR 1910.1000, the Federal Occupational Safety and Health Administration designates that worker exposure to certain gases and vapors must not be exceeded in workplace atmospheres at concentrations above specific values, averaged over a certain time span. Hydrogen sulfide is included in this list. Refer also to NIOSH Criteria for a Recommended Standard, Occupational Exposure to Hydrogen Sulfide.5.3 This practice will provide means for the determination of airborne concentrations of hydrogen sulfide.5.4 This practice provides means for either personal or area sampling and for short-term or time-weighted average (TWA) measurements. Refer to Threshold Limit Values for Chemical Substances in the Work Environment.1.1 This practice covers the detection of hydrogen sulfide gas by visual chemical detectors. Included under visual chemical detectors are: short-term detector tubes (1),2 long-term detector tubes (2), and length-of-stain dosimeters (3). Diffusion tubes are not included under this practice because they are not direct reading, and spot tests are not included because of their poor accuracy. The sample results are immediately available by visual observation, thus no analytical equipment is needed.1.2 This practice reflects the current state-of-the-art for commercially available visual length-of-stain detectors for hydrogen sulfide. Any mention of a specific manufacturer in the text or references does not constitute an endorsement by ASTM.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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 The fiber length of an HECP plays a role in the ability of the HECP to effectively be mixed and applied. This standard can be used by manufacturers to evaluate their manufacturing process (quality assurance/quality control). Laboratories can also use this method for quality assurance/quality control and also conformance to criteria testing.NOTE 1: The quality of the result produced by these test methods is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of these test methods are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 Hydraulic erosion control product (HECP) fibers are manufactured and processed to specific length and width dimensions to facilitate the hydraulic application and to prevent clogging of the pump, recirculation pipes, nozzles, and tips. This test method is used to determine the length of the fibers on a percentage basis in an HECP.1.2 This test method can be used to evaluate an HECP during and after manufacturing. The results can be used for comparative evaluations of the manufacturing process.1.3 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. Sieve designations are shown in both the standard and alternative designations.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 The procedures used to specify how data are collected/recorded or calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.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

4.1 Two types of alkali reactivity of aggregates have been described in the literature: the alkali-silica reaction involving certain siliceous rocks, minerals, and artificial glasses (1),3 and the alkali-carbonate reaction involving dolomite in certain calcitic dolomites and dolomitic limestones (2). This test method is not recommended as a means to detect combinations susceptible to expansion due to alkali-silica reaction since it was not evaluated for this use in the work reported by Buck (2). This test method is not applicable to aggregates that do not contain or consist of carbonate rock (see Descriptive Nomenclature C294).4.2 This test method is intended for evaluating the behavior of specific combinations of concrete-making materials to be used in the work. However, provisions are made for the use of substitute materials when required. This test method assesses the potential for expansion of concrete caused by alkali-carbonate rock reaction from tests performed under prescribed laboratory curing conditions that will probably differ from field conditions. Thus, actual field performance will not be duplicated due to differences in wetting and drying, temperature, other factors, or combinations of these (see Appendix X1).4.3 Use of this test method is of particular value when samples of aggregate from a source have been determined to contain constituents that are regarded as capable of participation in a potentially deleterious alkali-carbonate rock reaction either by petrographic examination, Guide C295/C295M, by the rock cylinder test, Test Method C586, by service record; or by a combination of these.4.4 Results of tests conducted as described herein should form a part of the basis for a decision as to whether precautions be taken against excessive expansion due to alkali-carbonate rock reaction. This decision should be made before a particular cement-aggregate combination is used in concrete construction (see Note 1).NOTE 1: Other elements that may be included in the decision-making process for categorizing an aggregate or a cement-aggregate combination with respect to whether precautions are needed, and examples of precautions that may be taken, are described in Appendix X1.4.5 While the basic intent of this test method is to develop information on a particular cement-aggregate combination, it will usually be very useful to conduct control tests in parallel using the aggregate of interest with other cements or the cement of interest with other aggregates.1.1 This test method covers the determination, by measurement of length change of concrete prisms, the susceptibility of cement-aggregate combinations to expansive alkali-carbonate reaction involving hydroxide ions associated with alkalies (sodium and potassium) and certain calcitic dolomites and dolomitic limestones.1.2 The text of this standard refers to notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.3 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. When combined standards are cited, the selection of measurement system is at the user's discretion subject to the requirements of the referenced standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 In-plane length measurements can be used in calculations of parameters, such as residual strain and Young's modulus.5.2 In-plane deflection measurements are required for specific test structures. Parameters, including residual strain, are calculated given the in-plane deflection measurements.1.1 This test method covers a procedure for measuring in-plane lengths (including deflections) of patterned thin films. It applies only to films, such as found in microelectromechanical systems (MEMS) materials, which can be imaged using an optical interferometer, also called an interferometric microscope.1.2 There are other ways to determine in-plane lengths. Using the design dimensions typically provides more precise in-plane length values than using measurements taken with an optical interferometric microscope. (Interferometric measurements are typically more precise than measurements taken with an optical microscope.) This test method is intended for use when interferometric measurements are preferred over using the design dimensions (for example, when measuring in-plane deflections and when measuring lengths in an unproven fabrication process).1.3 This test method uses a non-contact optical interferometric microscope with the capability of obtaining topographical 3-D data sets. It is performed in the laboratory.1.4 The maximum in-plane length measured is determined by the maximum field of view of the interferometric microscope at the lowest magnification. The minimum deflection measured is determined by the interferometric microscope’s pixel-to-pixel spacing at the highest magnification.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 Maps, automobile odometers, and highway and distance markers are not sufficiently accurate to describe the length of a route for tire testing purposes. The proposed procedure describes a test method for measuring the length of a road course with sufficient accuracy for tire testing purposes.1.1 This test method covers the determination of the accurate length measurement of road courses used for testing all types of pneumatic tires on various associated vehicles.1.2 This test method is intended for use on public highways or closed circuit test courses, or both, that cannot be measured practically by surveying techniques.1.3 Use of this test method requires that the surface of the test course to be measured shall be sufficiently smooth to preclude bounce or hop of the fifth wheel, which will affect the accuracy of the measurement. The normal highway surface is adequate for this test method.1.4 It is not the intent or scope of this test method to encompass distance measurements of test courses whose surfaces are irregular, broken up, jagged, and so forth, such as rock courses, Belgian block, “rumble” surfaces, and the like. Snow- and ice-covered surfaces also are excluded.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.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 and health 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.

定价： 515元 / 折扣价： 438 元 加购物车

5.1 Knowledge of the average fiber length and the distribution of fibers is of primary importance to users of top in further processing.5.2 Acceptance specifications for the fiber length and length distribution may be established by the user based on the type of yarn-making equipment employed and the desired end uses.5.3 Test Method D519 for testing wool top for fiber length is considered satisfactory for acceptance testing of commercial shipments since the method has been used extensively in the trade for acceptance testing and the current estimates of the between-laboratory precisions are acceptable.5.3.1 In case of a dispute arising from differences in reported test results when using this test method for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative testing to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogenous as possible and that are from a lot of the type material in question. The test specimens should then be assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found either its cause must be found and corrected or the purchaser and supplier must agree to interpret future test results in the light of the known bias.  (Front View)       (Rear View)  1—Frame.       5—Drawing clamp.  2—Faller bars.       6—Depressor.  3—Side comb.       7—Plush board.  4—Retaining bars.       8—Faller bar lifting plate.FIG. 1 Wool Fiber Stapling ApparatusTABLE 1 Form with Recorded Data Showing the Calculation of the Average Fiber Length of Wool, the Standard Deviation, and Coefficient of VariationNote 1—When using equipment graduated in metric units, use class intervals 10 mm long, and calculate the average and standard deviation to the nearest 0.2 mm.Class Intervals, in. Mass, g Percentages Cumulative FrequenciesFirst Cumulative,less than Second Cumulative,less than6.0 to 6.5 0.014   2.4 100.0  840.15.5 to 6.0 0.010   1.7  97.6  740.15.0 to 5.5 0.013   2.2  95.9  642.54.5 to 5.0 0.018   3.1  93.7  546.64.0 to 4.5 0.038   6.5  90.6  452.93.5 to 4.0 0.051   8.7  84.1  362.33.0 to 3.5 0.062  10.6  75.4  278.22.5 to 3.0 0.072  12.3  64.8  202.82.0 to 2.5 0.079  13.5  52.5  138.01.5 to 2.0 0.080  13.6  39.0   85.51.0 to 1.5 0.065  11.0  25.4   46.50.5 to 1.0 0.045   7.7  14.4   21.1  0 to 0.5 0.039   6.7   6.7    6.7                      Totals 0.586 100.0 = ∑ 840.1 4363.3  Divided by ∑percentages F 1 = 8.40 F 2 = 43.63B = the largest midpoint value for which a frequency is recorded = 6.25 in.m = the class interval = 0.5 in.Percentage of fibers under 2 in. = 39.0 %.Calculations:v = 100 (σ/X) = 100 × (1.4/2.6) = 56.47 %.where:X   =   average fiber length of wool,s   =   standard deviation, andv   =   coefficient of variation.1.1 This test method covers the measurement of the average length and length distribution of fibers in wool top, on a mass-biased basis. The method is applicable to all types of fibers in sliver formed from long parallelized fibers.Note 1—The determination of fiber length of wool is covered in Test Method D1575, Test Method for Fiber Length of Wool in Scoured Wool and in Card Sliver, the staple length of grease wool is covered in Test Method D1234, Test Method of Sampling and Testing Staple Length of Grease Wool.Note 2—This test method specifically requires length in inches and mass in SI units and is not contrary to ASTM policy. The SI units in parentheses are provided for information only.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 and health practices and determine the applicability of regulatory limitations prior to use.

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