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4.1 The measurement of soluble oxidizable components of cellulose in sodium hydroxide is indicative of the purity of the cellulose sample, since pure cellulose is insoluble in sodium hydroxide. The extracted components are typically hemicelluloses, which are naturally present in the wood. Differences in pulp purity can have a dramatic impact on the processing and properties of the cellulose derivatives produced from the pulp.1.1 This test method2 is intended for application to dissolving-type cellulose pulps prepared from cotton or wood. The procedure is not directly applicable to unrefined pulps for use in chemical conversion processes because solubility equilibrium may not be attained within the specified extraction time.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

The use of GaAs for semiconductor devices requires a consistent atomic lattice structure. However, lattice or crystal line defects of various types and quantities are always present, and rarely homogeneously distributed. It is important to determine the mean value and the spatial distribution of the etch pit density.1.1 This test method is used to determine whether an ingot or wafer of gallium arsenide is monocrystalline and, if so, to measure the etch pit density and to judge the nature of crystal imperfections. To the extent possible, it follows the corresponding test method for silicon, Test Method F 47. Test Method F 47 also presents the definition of many crystallographic terms, applicable to this test method. 1.2 This procedure is suitable for gallium arsenide crystals with etch pit densities between 0 and 200 000/cm2. 1.3 Gallium arsenide, either doped or undoped, and with various electrical properties, may be evaluated by this test method. The front surface normal direction of the sample must be parallel to the <001> within ± 5° and must be suitably prepared by polishing or etching, or both. Unremoved processing damage may lead to etch pits, obscuring the quality of the bulk crystal. 1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 8.

定价： 0元 / 折扣价： 0 元

4.1 Anion impurities in caustic soda and caustic potash are monitored by manufacturers and users for quality control of the products. Anions of primary interest are chloride, chlorate, and sulfate. This test method has determined precision estimates only for these three impurities.1.1 This test method covers the determination of anionic impurities in 50 % caustic soda (sodium hydroxide) and 50 % caustic potash (potassium hydroxide) solutions using ion chromatography (IC). Anions that can be determined at concentrations of approximately 0.1 to 1000 ug/g (ppm) include: bromide, chlorate, chloride, fluoride, nitrate, phosphate, and sulfate.1.2 By varying the sample size, this test method can be used for anhydrous caustic soda and caustic potash products, as well as other concentrations of liquid products.1.3 This test method is not intended to be used to quantify chloride in caustic soda where the sodium chloride concentration is approximately 1 %. For the most accurate determinations, it is recommended that high concentrations of chloride be analyzed using a potentiometric titration procedure, such as the one described in Test Methods E291.1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.5 Review the current appropriate Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safety precautions.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. Specific hazards statements are given in Section 8.

定价： 590元 / 折扣价： 502 元 加购物车

3.1 Caustic soda and caustic potash are used in a large number of manufacturing processes. The chemicals are available in several grades depending on their intended use. The test methods listed in 1.2 provide procedures for analyzing caustic soda and caustic potash to determine if they are suitable for their intended use.1.1 These test methods cover only the analyses usually required on the following commercial products:1.1.1 Caustic soda (sodium hydroxide), 50 and 73 % liquors; anhydrous (solid, flake, ground, or powdered), and1.1.2 Caustic potash (potassium hydroxide), 45 % liquor; anhydrous (solid, flake, ground, or powdered).1.2 The analytical procedures appear in the following order:Alkalinity (Total), Titrimetric (for 50 to 100 % NaOH and 45 to 100 % KOH) 3 to 4Carbonate, Gas-Volumetric (0.001 g CO2, min) 4 to 7Carbonate, Gravimetric (0.001 g CO2, min) 7 to 10Chloride, Titrimetric, (0.001 g Cl−, min) 10 to 11Chloride, Potentiometric Titration (0.3 to 1.2 %) 11 to 12Chloride, Ion Selective Electrode (0.6 to 120 μg/g) 12 to 13Iron, Photometric (0.005 mg Fe, min) 13 to 15Sulfate, Gravimetric, (0.002 g SO3, min) 15 to 16Keywords 161.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard with the exception of inch-pound units for apparatus descriptions.1.4 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29.1.5 Review the current Safety Data Sheet (SDS) for detailed information concerning toxicity, first-aid procedures, handling, and safety precautions.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 6.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Glass fiber reinforcing meshes are used to strengthen EIFS. The reinforcing meshes are embedded into base coats that contain portland cement, which potentially exposes the glass fibers in the reinforcing meshes to weakening by the action of alkali. The breaking force following alkali exposure as determined by this method, is a factor used to comparatively evaluate the alkali resistance of EIFS glass fiber reinforcing meshes in the laboratory.5.2 This test method does not purport to simulate the conditions that may be encountered in service. The performance of an EIFS is a function of many factors, such as proper installation, rigidity of supporting construction and resistance of the EIFS to deterioration by other causes.1.1 This test method covers procedures for determining the breaking force of glass fiber mesh following their conditioning in an alkali solution. The method is applicable to glass fiber mesh used in Class PB Exterior Insulation and Finish Systems (EIFS) with base coats that contain portland cement as an ingredient.1.2 Breaking force is expressed both as force per unit width of mesh and as a percentage of the breaking force of the mesh that has not been exposed to alkali conditioning.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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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 Information regarding the percentage of immature fibers is desirable because immature fibers: (1) break easily during processing; (2) have a tendency to form neps; (3) have a tendency to become entangled around particles of trash and leaf, thus making cleaning more difficult and increasing the amount of fiber removed with foreign matter; (4) adversely affect yarn and fabric appearance; and (5) may appear differently after dyeing.5.2 Maturity has a high positive correlation with linear density, but genetic differences and differences in wall thickness caused by plant diseases, soil, and water conditions during the growing season interfere with this relationship. Thus two cottons having the same linear density, or having the same average wall thickness as indicated by air-flow instruments, may vary greatly in maturity, that is, a cotton having extremely variable wall thickness may contain more immature fibers than another cotton of the same Micronaire reading composed of fibers having very uniform wall thickness.5.3 The Sodium Hydroxide Swelling (Procedure 1) has been used in judging other maturity tests such as the Causticaire and the differential dye methods, in which the individual fibers are not examined.5.4 Finer distinctions between different degrees of fiber wall development can be made with the Polarized Light procedure than with the Sodium Hydroxide Swelling procedure. The Polarized Light procedure gives a view of the fiber in its natural state so that fibrillar structure, striations, reversals, etc., are clearly visible as are growth abnormalities and variations in wall thickness. This method may be preferred by botanists, geneticists, and plant physiologists, while the Sodium Hydroxide Swelling procedure may be preferred for routine testing of large numbers of samples. Technicians are more easily trained for the latter method. Arbitrary classification as to maturity must be made with both methods.5.5 This method is not considered satisfactory for acceptance testing because between laboratory precision can be poor. In some cases the purchaser and seller may have to test a commercial shipment of one or more specific material by an appropriate method even though the method has not been recommended for acceptance testing of commercial shipments. In such a case, if there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, ensure the test samples to be used are as homogeneous as possible, are drawn from the material from which the disparate test result were obtained, and randomly assigned in equal numbers to each laboratory for testing. The test results from the two laboratories should be compared using statistical test for unpaired data, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.1.1 This test method covers the determination of the percentage of mature fibers in a sample of loose, chemically untreated cotton fibers, whether taken before processing or unravelled from a textile product.1.2 This test method gives two optional procedures for determining maturity, as follows:1.2.1 Procedure 1—Sodium Hydroxide Swelling.1.2.2 Procedure 2—Polarized Light.NOTE 1: For other test methods for the determination of maturity of cotton fibers refer to Test Methods D1464 and D2480.1.3 The values stated in SI units are to be regarded as standard. No other units of measure 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

4.1 Mercury is a toxic material and is also deleterious if present in caustic soda and caustic potash used in certain manufacturing processes. It must therefore be controlled as a possible pollutant. These test methods provide a procedure for measuring mercury in liquid and solid caustic soda and caustic potash.1.1 These test methods cover the routine determination of mercury in caustic soda and caustic potash liquors and anhydrous caustic soda in the solid, flake, ground, and bead form by the flameless atomic absorption method.1.2 Two test methods are described as follows: Test Method A employs a direct analysis of the sample using an alkaline reducing agent with a lower limit of detection of 0.1 ppb (ng/g). Test Method A was developed using caustic soda and caustic potash. Test Method B requires a preliminary neutralization of the sample followed by a permanganate oxidation before it can be analyzed by an acidic reducing agent with a lower limit of detection of this test method of 0.01 ppm (μg/g). Test Method B was developed using caustic soda.1.3 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first-aid procedures, and safety precautions.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 and health practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Sections 7 and 18.1.6 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： 0元 / 折扣价： 0 元

定价： 156元 / 折扣价： 133 元 加购物车

5.1 Hydroxyl is an important functional group and knowledge of its content is required in many intermediate and end use applications. This test method is for the determination of primary and secondary hydroxyl groups and can be used for the assay of compounds containing them.5.2 This test method has the following advantages over other hydroxyl number methods: It is rapid (10 min), pyridine-free, ambient temperature, small sample size, applicable to extremely low hydroxyl numbers (<1), and is amenable to automation.1.1 This test method covers the determination of hydroxyl groups attached to primary and secondary carbon atoms in aliphatic and cyclic compounds and phenols from 0.5 to 367 hydroxyl number. It is not suitable for determination of hydroxyl groups attached to tertiary carbon atoms. This test method is applicable to polyacetals, temperature sensitive materials, high solids polymer polyols, and rigid polyols. Other available test methods listed in Note 1 are not suitable for many of the sample types listed above.1.1.1 This test method is currently recommended for neutral refined products. Successful application has been made, however, to some in-process samples that contain an excess of acidic species. Proper validation must be performed, of course, to show that the acidic species either does not interfere, or that the acidic species interference has been obviated.NOTE 1: Other methods for determination of hydroxyl groups are given in Test Methods D817, D871, D4252, D4273, D4274, E222, E326, and E335.1.2 The Limit of Detection (LOD) is 0.18 units and the Limit of Quantitation (LOQ) is 0.59 units. Unit = hydroxyl number (OH#).NOTE 2: LOD and LOQ were calculated using Standard deviations from 14.1.2.1.1.3 Review the current appropriate Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safety precautions.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 The following applies for the purposes of determining the conformance of the test results using this test method to applicable specifications. Results shall be rounded off in accordance with the rounding-off method of Practice E29.1.6 This standard does not purport to address all of the safety concerns, if any, associated, with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazards see Section 9.1.7 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： 590元 / 折扣价： 502 元 加购物车

2.1 Hot alkali extracts low molecular weight carbohydrates consisting mainly of hemicellulose and degraded cellulose in wood. This solubility of wood is an indication of the degree of fungal decay, or degradation by heat, light, oxidation, and so forth. The more decay or degradation, the higher the solubility.1.1 This test method covers the determination of the solubility of wood in a hot dilute alkali solution. A1 % solution of sodium hydroxide (NaOH) is used. One application is in determining the degree of fungus decay that has taken place in a given wood sample. As the wood decays, the percentage of alkali-soluble material increases in proportion to the decrease in pulp yield caused by the decay.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