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4.1 The ability of a plastic material to resist deterioration caused by exposure to light, heat, and water is a property of significance in many applications. This practice is intended to induce property changes associated with end-use conditions, including the effects of ultraviolet solar irradiance, moisture, and heat. The exposure used in this practice is not intended to simulate the deterioration caused by localized weather phenomena, such as, atmospheric pollution, biological attack, and saltwater exposure. (Warning—Variation in operating conditions within the accepted limits of this practice will not necessarily provide the same results. Therefore, no reference to the use of this practice shall be made unless accompanied by a report prepared in accordance with Section 8 that describes the specific operating conditions used. Refer to Practice G151 for detailed information on the caveats applicable to use of results obtained in accordance with this practice.)NOTE 2: Additional information on sources of variability and on strategies for addressing variability in the design, execution, and data analysis of laboratory-accelerated exposure tests is found in Guide G141.4.2 Reproducibility of test results between laboratories has been shown to be good when the stability of materials is evaluated in terms of performance ranking compared to other materials or to a control.5,6 Therefore, exposure of a similar material of known performance (a control) at the same time as the test materials is strongly recommended. It is recommended that at least three replicates of each material be exposed to allow for statistical evaluation of results.4.3 Test results will depend upon the care that is taken to operate the equipment in accordance with Practice G154. Significant factors include regulation of line voltage, temperature of the room in which the device operates, temperature control, and condition and age of the lamp.1.1 This practice covers specific procedures and test conditions that are applicable for using a fluorescent UV lamp and water apparatus exposure of plastics conducted in accordance with Practices G151 and G154. This practice also covers the preparation of test specimens, the test conditions best suited for plastics, and the evaluation of test results.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.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.NOTE 1: This standard and ISO 4892-3 address the same subject matter, but differ in technical contact.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 method directly determines the concentration of metal cyanide complexes in environmental waters. The method is important from an environmental regulatory perspective because it differentiates metal cyanide complexes of lesser toxicity from metal cyanide complexes of greater toxicity. Previous determinations of strong metal cyanide complexes assumed that the concentration of strong metal cyanide complexes is equivalent to the difference between the total cyanide and the free cyanide. This approach is subject to error because different methods used to determine free cyanide often provide widely varying results, thus impacting the strong metal cyanide complex concentration that is determined by difference. The direct analysis using anion exchange chromatography avoids these method biases and provides for a more accurate and precise determination of metal cyanide complexes.1.1 This test method covers the determination of the metal cyanide complexes of iron, cobalt, silver, gold, copper and nickel in waters including groundwaters, surface waters, drinking waters and wastewaters by anion exchange chromatography and UV detection. The use of alkaline sample preservation conditions (see 10.3) ensures that all metal cyanide complexes are solubilized and recovered in the analysis (1-3).21.2 Metal cyanide complex concentrations between 0.20 to 200 mg/L may be determined by direct injection of the sample. This range will differ depending on the specific metal cyanide complex analyte, with some exhibiting greater or lesser detection sensitivity than others. Approximate concentration ranges are provided in 12.2. Concentrations greater than the specific analyte range may be determined after appropriate dilution. This test method is not applicable for matrices with high ionic strength (conductivity greater than 500 meq/L as Cl) and TDS (greater than 30 000 mg/L), such as ocean water.1.3 Metal cyanide complex concentrations less than 0.200 mg/L may be determined by on-line sample preconcentration coupled with anion exchange chromatography as described in 11.3. This range will differ depending on the specific metal cyanide complex analyte, with some exhibiting greater or lesser detection sensitivity than others. Approximate concentration ranges are provided in 12.2. The preconcentration method is not applicable for silver and copper cyanide complexes in matrices with high TDS (greater than 1000 mg/L).1.4 The test method may also be applied to the determination of additional metal cyanide complexes, such as those of platinum and palladium. However, it is the responsibility of the user of this standard to establish the validity of the test method for the determination of cyanide complexes of metals other than those in 1.1.1.5 The presence of metal complexes within a sample may be converted to Metal CN complexes and as such, are altered with the use of this method. This method is not applicable to samples that contain anionic complexes of metals that are weaker than cyanide complexes of those metals.1.6 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered 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 and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, refer to Section 9.

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