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本文件描述了采用液相色谱-质谱法(LC-ESI-MS)测定纺织品中绵羊毛、山羊绒、牦牛绒及其混合物含量的定性和定量分析方法。
本文件适用于含有动物毛纤维及其混合物的各类纺织产品。
本文件不适用于同一物种动物纤维混合物(如山羊绒和马海毛的混合物)的鉴别。

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DB32/T 458-2001 W-LC轻质高强镁质复合墙板施工及验收规程 现行 发布日期 :  2001-03-06 实施日期 :  2001-04-01

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5.1 PFAS are widely used in various industrial and commercial products; they are persistent, bio-accumulative, and ubiquitous in the environment. PFAS have been reported to exhibit developmental toxicity, hepatotoxicity, immunotoxicity, and hormone disturbance. PFAS have been detected in soils, sludges, surface, and drinking waters. This is a quick, easy, and robust method to quantitatively determine these compounds at trace levels in water matrices.5.2 This test method has been validated using reagent water and waters from sites that include landfill leachate, metal finisher, POTW Effluent, Hospital, POTW Influent, Bus washing station, Power Plant and Pulp and paper mill effluent for selected PFAS, refer to the Precision and Bias (Section 17).1.1 This test method covers the determination of per- and polyfluoroalkyl substances (PFASs) in aqueous matrices using liquid chromatography (LC) and detection with tandem mass spectrometry (MS/MS). These analytes are co-solvated by a 1+1 ratio of sample and methanol then qualitatively and quantitatively determined by this test method. Quantitation is by selected reaction monitoring (SRM) or sometimes referred to as multiple reaction monitoring (MRM).1.2 The method detection limit (MDL) (see Note 1) and reporting range (see Note 2) for the target analytes are listed in Table 1. The target concentration for the reporting limit for this test method is an integer value that is calculated from the concentration from the lowest standard from the final volume of the prepared sample. This value may be lower than the calculated MDL due to sporadic PFAS hits due to PFAS contamination in consumables/collection tools used during sample collection and preparation. All samples should be taken at a minimal as duplicates in order to compare the precision between the two prepared samples to help ensure the concentration/positive result is reliable.NOTE 1: The MDL is determined following the Code of Federal Regulations (CFR), 40 CFR Part 136, Appendix B utilizing dilution and filtration. A detailed process determining the MDL is explained in the reference and is beyond the scope of this test method.NOTE 2: Injection volume variations, and sensitivity of the instrument used will change the reporting limit and ranges.1.2.1 Recognizing continual advancements in the sensitivity of instrumentation, advancements in column chromatography and other processes not recognized here, the reporting limit may be lowered assuming the minimum performance requirements of this test method at the lower concentrations are met.1.2.2 Depending on data usage, you may modify this test method but limit to modifications that improve performance while still meeting or exceeding the method quality acceptance criteria. Modifications to the solvents, ratio of solvent to sample, or shortening the chromatographic run simply to save time are not allowed. Use Practice E2935 or similar statistical tests to confirm that modifications produce equivalent results on non-interfering samples. In addition, use Guide E2857 or equivalent statistics to re-validate the modified test.1.2.3 Analyte detections between the method detection limit and the reporting limit are estimated concentrations. The reporting limit is based upon the concentration of the Level 1 calibration standard as shown in Table 5.1.3 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.

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5.1 This is a performance-based method, and modifications are allowed to improve performance.5.1.1 Due to the rapid development of newer instrumentation and column chemistries, changes to the analysis described in this standard are allowed as long as better or equivalent performance data result. Any modifications shall be documented and performance data generated. The user of the data generated by this standard shall be made aware of these changes and given the performance data demonstrating better or equivalent performance.5.2 TDG is a Schedule 2 compound under the Chemical Weapons Convention (CWC).6 Schedule 2 chemicals include those that are precursors to chemical weapons, chemical weapons agents, or have a number of other non-military commercial uses. Schedule 2 chemicals can also be found in applications unrelated to chemical weapons. These chemicals are used as ingredients to produce insecticides, herbicides, lubricants, and some pharmaceutical products. TDG is a mustard gas precursor and a degradant as well as an ingredient in water-based inks, ballpoint pen inks, dyes, and some pesticides.5.3 This method has been investigated for use on surface wipes. TDG is also a human metabolite resulting from sulfur mustard exposure but this method has not been investigated for such determinations.1.1 This procedure details the determination of thiodiglycol (TDG), also known as 2,2’-thiobis-ethanol, on wipes with 3,3’-thiodipropanol (TDP) as the surrogate. This method is based upon solvent extraction of wipes by either sonication or a pressurized fluid extraction (PFE) technique as an alternative option. The extract is filtered, concentrated, and analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS). TDG is qualitatively and quantitatively determined.1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 The method detection limit (MDL)2 and reporting range3 for TDG are listed in Table 1.1.4 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 The crystallinity of petroleum coke, as reflected by the Lc value, is a general measure of quality affecting suitability for end use and is a function of the heat treatment.5.2 The crystallite thickness is used to determine the extent of such heat treatment, for example, during calcination. The value of the Lc determined is not affected by coke microporosity or the presence of foreign, non-crystalline materials such as dedust oil.1.1 This test method covers the determination of the mean crystallite thickness of a representative, pulverized sample of calcined petroleum coke by interpretation of a X-ray diffraction pattern produced through conventional X-ray scanning techniques.1.2 Calcined petroleum coke contains crystallites of different thicknesses. This test method covers the determination of the average thickness of all crystallites in the sample by empirical interpretation of the X-ray diffraction pattern. The crystallite diameter (La) is not determined by this test method.1.3 The values stated in SI (metric) units are to be regarded as the standard. The inch-pound units given in parentheses are provided for information purposes 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.

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5.1 Nitrosamines are a class of nitrogen-containing compounds with a known occurrence in wastewater. They may also be created in deionization and are a potential contaminant in water for reuse. The World Health Organization has issued a guideline for NDMA in drinking water at 0.1 µg/L. NDMA may occur in chlorinated effluents and other wastewaters. Other methods for nitrosamines employ solid phase extraction, which may not be applicable to wastewaters that contain particulate matter or a high organic load. This method analyses nitrosamines directly using LC-MS/MS.1.1 This test method covers the liquid chromatography tandem mass spectrometry (LC-MS/MS) detection and quantitation of N-nitrosamines after direct injection. It has been validated for groundwater, surface water, wastewater influents, and wastewater effluents. This test method is not limited to these aqueous matrices; however, the applicability of this test method to other aqueous matrices must be demonstrated.1.2 This test method is applicable to nitrosamines that can be chromatographed and detected using a mass spectrometry procedure. Table 1 lists the compounds that have been validated for this test method. This test method is not limited to the compounds listed in Table 1; however, the applicability of the test method to other compounds must be demonstrated.1.3 Analyte concentrations from 0.05 µg/L up to approximately 5 µg/L may be determined without dilution of the sample. Analytes with insufficient sensitivity will not be detected, but they can be measured with acceptable accuracy and precision when present in sufficient amounts. In addition, newer instruments, or instruments of improved sensitivity may be used to lower detection limits.1.4 Analytes that are not separated chromatographically, but that have different mass spectra and noninterfering quantitation ions, can be identified and measured in the same calibration mixture or water sample. Analytes that have very similar product ions cannot be individually identified and measured in the same calibration mixture or water sample unless they have different retention times.1.5 It is the responsibility of the user to ensure the validity of this test method for untested matrices.1.6 This test method is restricted to use by or under the supervision of analysts experienced in the use of a liquid chromatograph with tandem mass spectrometry (LC-MS/MS).1.7 Depending on data usage, you may modify this test method but limit to modifications that improve performance while still meeting method quality acceptance criteria. Shortening the chromatographic run simply to save time is not allowed. Use Practice E2935 or similar statistical tests to confirm that modifications produce equivalent results on non-interfering samples. In addition, use Guide E2857 or equivalent statistics to re-validate the modified test.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.9 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.1.10 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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ANSI/CSA LC 3-2000 Appliance Stands and Drain Pans 现行 发布日期 :  1970-01-01 实施日期 : 

Scope These requirements apply to appliance stands which are used for supporting an appliance at the proper height to meet appliance codes requiring flammable vapor ignition sources, (such as burners, burner ignition devices, electrical heating elements

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