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定价： 345元 / 折扣价： 294 元

定价： 156元 / 折扣价： 133 元 加购物车

定价： 156元 / 折扣价： 133 元

This specification establishes the properties and test methods for aqueous dispersions of polytetrafluoroethylene (PTFE) resins, and is used to determine if a shipment, lot, or container of PTFE dispersions is suitable for its intended use. These resins are homopolymers of tetrafluoroethylene, or in some cases modified homopolymers containing not more than 1% by weight of other fluoromonomers, and the dispersions are usually stabilized by one or more surfactants. Other non-PTFE materials may be present in total at 5% or less by weight for special purposes. This specification is for virgin materials only, and does not cover PTFE copolymers or filled dispersions, and recycled materials as they are not appropriate for dispersions. Materials shall be appropriately sampled for testing on the following: pH value; solid and surfactant content by gravimetric weight loss; solid content by hydrometer; test for coagulated polymer; specific gravity; and melting characteristics.1.1 This specification covers aqueous dispersions of polytetrafluoroethylene (PTFE) resins. These resins are homopolymers of tetrafluoroethylene, or in some cases modified homopolymers containing not more than 1 % by weight of other fluoromonomers.1.1.1 The dispersion is usually stabilized by one or more surfactants. Other non-PTFE materials may be present in total at 5 % or less by weight for special purposes.1.1.2 This specification is for virgin material only and does not address recycled material as it is not appropriate for dispersions.1.2 This specification is used to determine if a shipment, lot, or container of PTFE dispersion is suitable for its intended use. It covers only aqueous dispersions of polytetrafluoroethylene. It does not cover PTFE copolymers or filled dispersions. This specification includes test methods for both aqueous dispersion and the PTFE in the dispersion.NOTE 1: Uses for the PTFE dispersion covered by this specification include, but are not limited to, casting of their films, impregnation of mechanical packings and other materials, surface coatings on various substrates, combined impregnation and coating of fibrous materials, and co-coagulation with other materials for subsequent processing into films, sheets, rods, and tubes.NOTE 2: Information in this specification is technically equivalent to related information in ISO 20568-1 and ISO 20568-2.1.3 The values stated in SI units as detailed in IEEE/ASTM SI-10 are to be regarded as standard. The values given in parentheses are for information only.1.4 The following precautionary caveat pertains only to the test method portions of this specification. 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 precautionary information is given in Notes 5 and 6.1.5 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 This practice is useful in identifying the major organic constituents in wastewater for support of effective in-plant or pollution control programs. Currently, the most practical means for tentatively identifying and measuring a range of volatile organic compounds is gas-liquid chromatography. Positive identification requires supplemental testing (for example, multiple columns, speciality detectors, spectroscopy, or a combination of these techniques).1.1 This practice covers general guidance applicable to certain test methods for the qualitative and quantitative determination of specific organic compounds, or classes of compounds, in water by direct aqueous injection gas chromatography (1, 2, 3, 4).21.2 Volatile organic compounds at aqueous concentrations greater than about 1 mg/L can generally be determined by direct aqueous injection gas chromatography.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： 590元 / 折扣价： 502 元 加购物车

5.1 Rubber articles, such as seals, gaskets, and membranes, may be exposed in service to chlorine compounds used in potable water as disinfectants. The exposure may be intermittent or continuous and can occur at various temperatures.5.2 Properties of rubber articles can deteriorate as a result of exposure to water containing these chlorine compounds, affecting their performance for the intended use.5.3 This test method attempts to simulate service conditions through controlled accelerated testing, but may not give a direct correlation with part performance under actual service conditions. It yields comparative data on which to base judgement on expected service quality.5.4 This test method is suitable for compliance testing, quality control, and research and development work.1.1 This test method covers procedures for evaluating the ability of rubber and rubber-like materials to withstand the effects of aqueous solutions with available chlorine and chloramine. It is intended to compare the effects of chlorine compounds, present in potable water due to disinfection procedures, on rubber articles.1.2 Test solutions are designed to contain chlorine compounds, including hypochlorous acid (HOCl), hypochlorite ions (OCl), and monochloramine (NH2Cl).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

1.1 This test method covers the general considerations for the qualitative and quantitative determination of volatile amines such as cyclohexylamine, morpholine, and diethylaminoethanol in steam condensates and surface water by gas-liquid chromatography. 1.2 This test method may be applied to water samples containing the amines in concentrations from 2 to 15 mg/L by direct injection of alkaline aqueous samples. Higher concentrations may be determined by appropriate dilution. 1.3 Although this test method is written for flame ionization detector, the basic technology is applicable to any highly sensitive nitrogen-specific detector provided water does not interfere with the measurement. 1.4 The test method may be extended to steam condensates containing low levels of these amines by adopting suitable concentration techniques such as steam distillation to bring the analyte concentration to an accurately quantifiable range. 1.5 The test method is applicable to other chromatographable amines by appropriately varying the chromatographic parameters. This must be validated by the individual analysts. 1.6 This test method has been used successfully with reagent-grade and boiler steam condensate waters. It is the user's responsibility to assure the validity of this test method for any untested matrices. 1.7 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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： 0元 / 折扣价： 0 元

The results obtained by this test method are useful as guides in determining the tendency of a water-based metalworking coolant to produce foam under low shear conditions. No correlation with changes in heat transfer, pumpability, or other factors affected by foam is intended. The foam generated by any given industrial process depends on the method by which the foam is generated and may not be directly proportional to that produced by this controlled laboratory test method. Further, the foam generated at the specified test temperature will not necessarily predict the foaming tendency of the liquid (that is, metalworking coolant) at some other use temperature.1.1 This test method covers the measurement of the increase in volume of a low-viscosity aqueous liquid (less than 3 cSt at 40°C) due to its tendency to foam under low shear conditions. Note 1 - Foam under high shear is covered by Test Method D 3519 which uses a commercial blender.<>1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.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 safety information, see 7.13.

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The pH values of the extracts give an indication of the acidity or alkalinity of the fiber and its water-soluble impurities. These values are useful in indicating previous processing and in anticipating subsequent performance. For particular purposes, the pH of an extract prepared by one method may be a more informative index than another and as a consequence four optional extraction procedures are included. This test method is not recommended for acceptance testing because the between-laboratory precision is relatively poor. In some cases, the purchaser and the seller may have to test a commercial shipment of one or more specific materials by the best available method, even though the method has not been recommended for acceptance testing of commercial shipments. In such a case, if there is disagreement arising from differences in values reported by the purchaser and the seller when using this method for acceptance testing, the statistical bias, if any, between the laboratory of the purchaser and the laboratory of the seller should be determined, with each comparison being based on testing specimens randomly drawn from one sample of material of the type being evaluated.1.1 This test method covers the determination of the pH of aqueous extracts from wool and similar animal fibers. It is applicable to fibers in any conditionraw wool, scoured wool, sliver, top, yarn, or fabric. 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. For specific precautionary statements, see Section 11.

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5.1 Pesticides and PCBs are Environmental Protection Agency (EPA)-regulated contaminants in treated drinking water, wastewater, and ground water. Liquid-liquid and solid-phase extraction (SPE) are generally applicable procedures for extracting these target analytes before GC/MS/MS analysis.5.2 This test method is applicable to pesticides that are extracted from aqueous solution using methylene chloride and can be chromatographed and detected using tandem mass spectrometry procedures. Table 1 lists pesticides and Table 2 lists PCBs validated by this test method. This test method is not limited to the compounds listed in Table 1 or Table 2; however, the applicability of the test method to other compounds shall be demonstrated. Refer to Guide E2857 for guidance in validating the method for additional parameters.5.3 Analyte concentrations up to approximately 250 ng/L may be determined. Analytes that are inefficiently extracted from water will not be detected when present at low concentrations, but they can be measured with acceptable accuracy and precision when present in sufficient amounts.5.4 Analytes that are not separated chromatographically but that have different transitions can be identified and quantitatively measured.5.5 This test method may be used to determine the concentrations of Aroclor6 mixtures or PCB congeners, or both, present in the sample. See Appendix X1 and Appendix X2 for suggested transitions and collisional energies for all 209 congeners. Separation of all 209 congeners may not be possible and may require additional GC columns and operating conditions. Analysis of all congeners is not expected to be achieved by this test method.5.6 Method detection limits (MDL) and minimum reporting level (MRL) for analytes in Tables 1 and 2 are given in Table 3. These limits must be met if the method is used for National Pollutant Discharge Elimination System (NPDES) reporting.(A) Priority Pollutant listed in Table 1 of EPA Method 608.3.(B) Priority Pollutant listed in Table 2 of EPA Method 608.3.1.1 This test method covers the identification and simultaneous measurement of extractable chlorinated pesticides and polychlorinated biphenyls (PCBs) by gas chromatography/mass spectrometry/mass spectrometry (GC/MS/MS).1.2 This test method has been validated for wastewater influents, effluents, industrial discharges, surface water, and ground water.1.3 This test method is not limited to these particular aqueous matrices; however, the applicability of this test method to other aqueous matrices shall be demonstrated.1.4 This test method is restricted to use by or under the supervision of analysts experienced in the use of a gas chromatograph with tandem mass spectrometry. Each laboratory that uses this test method shall demonstrate the ability to generate results that meet or exceed the performance criteria of this test method.1.5 If sensitivity permits, compound tentative identification of unknowns may be made by analyzing the extract in full-scan mode or, if the system allows simultaneous timed single-reaction monitoring (SRM)/full-scan acquisition. Identify unknown peaks according to Guide D4128.1.6 This test method is performance-based. Minor modifications, as allowed by CFR 40 Part 136.6, may be made to improve the method performance, but changes may not be made to the extraction, the extraction solvent, sample-to-solvent ratio, or the MS/MS detection technique.1.7 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.8 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.1.9 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 An acute effluent toxicity test is conducted to obtain information concerning the immediate effects on test organisms of a short-term exposure to an effluent under specific experimental conditions. One can directly examine acute effects of complex mixtures of chemicals as occurs in effluents and some ambient waters. Acute effluent toxicity tests can be used to evaluate the potential for designated-use or aquatic life impairment in the receiving stream, lake, or estuary. An acute toxicity test does not provide information about whether delayed effects will occur, although a post-exposure observation period, with appropriate feeding if necessary, might provide such information.5.2 Results of acute effluent tests might be used to predict acute effects likely to occur on aquatic organisms in field situations as a result of exposure under comparable conditions, except that (1) motile organisms might avoid exposure when possible, (2) toxicity to benthic species might be dependent on sorption or settling of components of the effluent onto the substrate, and (3) the effluent might physically or chemically interact with the receiving water.5.3 Results of acute effluent tests might be used to compare the acute sensitivities of different species and the acute toxicities of different effluents, and to study the effects of various environmental factors on results of such tests.5.4 Acute tests are usually the first step in evaluating the effects of an effluent on aquatic organisms.5.5 Results of acute effluent tests will depend on the temperature, composition of the dilution water, condition of the test organisms, exposure technique, and other factors.AbstractThis guide covers procedures for obtaining laboratory data concerning the adverse effects of aqueous ambient samples and effluents on certain species of freshwater and saltwater fishes, macroinvertebrates, and amphibians, during a short-term exposure, depending on the species, using the static, renewal, and flow-through techniques. These procedures will probably be useful for conducting acute toxicity tests on aqueous effluents with many other aquatic species, although modifications might be necessary. Static tests might not be applicable to effluents that have a high oxygen demand, or contain materials that (1) are highly volatile, (2) are rapidly biologically or chemically transformed in aqueous solutions, or (3) are removed from test solutions in substantial quantities by the test chambers or organisms during the test. Results of acute toxicity tests should usually be reported in terms of a median lethal concentration (LC50) or median effective concentration (EC50). An acute toxicity test does not provide information about whether delayed effects will occur. Specified requirements involving the following are detailed: (1) hazards; (2) apparatus: facilities, special requirements, construction materials, metering system, test chambers, cleaning, and acceptability; (3) dilution water requirements, source, treatment, and characterization; (4) effluent sampling point, collection, preservation, treatment, and test concentrations; (5) test organism species, age, source, care and handling, feeding, disease treatment, holding, acclimation, and quality; (6) procedure: experimental design, dissolved oxygen, temperature, loading, beginning the test, feeding, duration of test, biological data, and other measurements; (7) analytical methodology; (8) acceptability of test; (9) calculation of results; and (1) report of results.1.1 This guide covers procedures for obtaining laboratory data concerning the adverse effects of an aqueous effluent on certain species of freshwater and saltwater fishes, macroinvertebrates, and amphibians, usually during 2 day to 4 day exposures, depending on the species, using the static, renewal, and flow-through techniques. These procedures will probably be useful for conducting acute toxicity tests on aqueous effluents with many other aquatic species, although modifications might be necessary.1.2 Other modifications of these procedures might be justified by special needs or circumstances. Although using appropriate procedures is more important than following prescribed procedures, results of tests conducted using unusual procedures are not likely to be comparable to results of many other tests. Comparison of results obtained using modified and unmodified versions of these procedures might provide useful information concerning new concepts and procedures for conducting acute toxicity tests on aqueous effluents.1.3 This guide is based in large part on Guide E729 where addition details are provided for test elements that may be applicable to the ambient and effluent toxicity testing described in this method. The major differences between the two guides are (1) the maximum test concentration is 100 % effluent or ambient sample, (2) testing is not chemical-specific, and (3) the holding time of effluent and ambient samples is often considerably less than that for chemicals and other test materials. Because the sample is often a complex mixture of chemicals, analytical tests cannot generally be used to confirm exposure concentrations.1.4 Selection of the technique to be used in a specific situation will depend upon the needs of the investigator and upon available resources. Static tests provide the most easily obtained measure of acute toxicity but should not last longer than 48 h. Renewal and flow-through tests may last longer than 48 h because the pH and concentrations of dissolved oxygen and effluent are maintained at desired levels and degradation and metabolic products are removed. Static tests might not be applicable to effluents that have a high oxygen demand or contain materials that (1) are highly volatile, (2) are rapidly biologically or chemically transformed in aqueous solutions, or (3) are removed from test solutions in substantial quantities by the test chambers or organisms during the test. Flow-through tests are generally preferable to renewal tests, although in some situations a renewal test might be more cost-effective than a flow-through test.1.5 In the development of these procedures, an attempt was made to balance scientific and practical considerations and to ensure that the results will be sufficiently accurate and precise for the applications for which they are commonly used. A major consideration was that the common uses of the results of acute tests on effluents do not require or justify stricter requirements than those set forth in this guide. Although the tests may be improved by using more organisms, longer acclimation times, and so forth, the requirements presented in this guide should usually be sufficient.1.6 Results of acute toxicity tests should usually be reported in terms of a median lethal concentration (LC50) or median effective concentration (EC50). In some situations, it might be necessary only to determine whether a specific concentration is acutely toxic to the test species or whether the LC50 or EC50 is above or below a specific concentration.1.7 This guide is arranged as follows:  Section   Referenced Documents   2Terminology   3Summary of Guide   4   5Hazards   7Apparatus   6 Facilities   6.1 Special Requirements   6.2 Construction Materials   6.3 Metering System   6.4 Test Chambers   6.5 Cleaning   6.6 Acceptability   6.7Dilution Water   8 Requirements   8.1 Source   8.2 Treatment   8.3 Characterization   8.4Effluent   9 Sampling Point   9.1 Collection   9.2 Preservation   9.3 Treatment   9.4 Test Concentration(s)   9.5Test Organisms   10 Species   10.1 Age   10.2 Source   10.3 Care and Handling   10.4 Feeding   10.5 Disease Treatment   10.6 Holding   10.7 Acclimation   10.8 Quality   10.9Procedure   11 Experimental Design   11.1 Dissolved Oxygen   11.2 Temperature   11.3 Loading   11.4 Beginning the Test   11.5 Feeding   11.6 Duration of Test   11.7 Biological Data   11.8 Other Measurements   11.9Analytical Methodology   12Acceptability of Test   13Calculation or Results   14Report   151.8 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 7.1.9 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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4.1 This practice is designed for researchers, applicators, and end users of pesticides where one or more ingredients are being mixed into an aqueous spray system. The practice is useful in determining physical compatibility of aqueous spray mixtures of pesticides and/or fertilizers.4.2 The practice is not designed to determine physical compatibility of non-aqueous based spray mixtures.4.3 The results or the testing should be used to determine the compatibility of the mixture ingredients in dynamic applications. Interpolation of static results to the expectations of the results of this test is not encouraged.1.1 This practice describes the method for the evaluation of the physical compatibility and stability of pesticide tank mixtures diluted for aqueous application. This practice may also be adapted to use with liquid fertilizers in replacement of the water diluent.1.2 Tank mix compatibility can be affected by many variables. Care should be taken to duplicate test conditions. This practice addresses the standard variables such as time, temperature, water hardness, method of agitation, and degree of agitation.1.3 Compatibility is complex and can be affected by other variables such as order of addition, pH of the dilution water, pumping shear, etc. Under the parameters of this practice, the results will define whether the pesticide mixture is or is not compatible in the laboratory. Compatibility or incompatibility should be confirmed under field spray conditions.1.4 Proper safety and hygiene precautions must be taken when working with pesticide formulations to prevent skin or eye contact, vapor inhalation, and environmental contamination.1.5 Read and follow all handling instructions for the specific formulation and conduct the test in accordance with good laboratory practice.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.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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This guide is intended as a general guide to the correct use of foams. Specific decisions on when or if foam should be used will depend on the circumstances and conditions of each spill situation.Polar solvent resistant AFFF can be applied to some water reactive chemicals with a medium expansion foam nozzle to extinguish a fire and to reduce toxic vapor release to the environment.1.1 This guide restricts itself to addressing the application of foam to water immiscible liquid and some water reactive compounds with boiling points above 15°C for vapor control or fire suppression of land spill or contained spills on water.1.2 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 non-conformance with the 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 and health practices and determine the applicability of regulatory limitations prior to use. For hazard statements, see Section 10.

定价： 0元 / 折扣价： 0 元

5.1 Matrix spiking is commonly used to determine the bias under specific analytical conditions, or the applicability of a test method to a particular sample matrix in that context, by determining the extent to which the spiked analyte or component is recovered from the sample matrix under these conditions. Reactions or interactions of the analyte or component of interest with the sample matrix may cause a significant positive or negative effect on recovery and may render the chosen analytical, or monitoring, process ineffectual for that sample matrix.5.2 Matrix spiking can also be used to monitor the performance of a laboratory, individual instrument, or analyst as part of a regular quality assurance program. Changes in spike recoveries or recovery limits from the same or similar matrices over time may indicate variations in the quality of analytical results.5.3 Spiking can be used to compare the recoveries of like spikes from reagent water samples and natural matrix samples (measured with and without spike) to distinguish between (1) unusual interference and (2) inherent method recovery and instability effects. This guide does not attempt to deal with the statistical significance of differences in spike recoveries from different matrices.5.4 Special precautions shall be observed when nonlaboratory personnel perform spiking in the field. It is recommended that all spike preparation work be performed in a laboratory by experienced analysts so that the field operation consists solely of adding a prepared spiking solution to the sample matrix. Training of field personnel and validation of their spiking techniques are necessary to ensure that spikes are added accurately and reproducibly. Duplicate field spikes can be used to document the reproducibility of the technique. When environmentally labile compounds are used as spikes, the spiking solution shall be protected up to the point of use by appropriate means such as chilling, protection from sunlight and oxygen, or chemical preservation.NOTE 1: Any field spiked sample, if known to the laboratory, should be labeled as a field spike in the final results report. Also, whenever possible, field spiking of volatile compounds should be avoided.5.5 It is often tacitly assumed that an analyte component is recovered from samples to approximately the same extent that a spike of the same analyte is recovered from a spiked sample. One reason that this assumption may be incorrect is that the spike may not be bound up in the sample (for example, with suspended matter) in the same way that the naturally occurring analyte is bound in the sample. The spike may therefore be recovered from the sample differently than the background level of the analyte. It is not good practice to correct analytical data using spike recoveries for this reason, as well as the fact that bias corrections can add variability. However, spike recovery information should be reported along with related sample analysis results.5.6 This guide is also applicable to the use of spikes for quantification by the method of standard additions and to the addition of surrogates and internal standards.1.1 This guide covers the general technique of “spiking” a broad range of materials into aqueous media. This guide will serve the analyst in preparing spiked samples for quality control purposes. Guidance is also provided to aid the analyst in calculating recoveries and interpreting results. It is the responsibility of the analyst to determine whether the procedures and materials described here are appropriate to the task at hand.1.2 The procedures in this guide are focused on “matrix spike” preparation, analysis, and interpretation of results. The applicability of these procedures to the preparation of calibration standards, calibration check standards, laboratory control standards, reference materials, and other quality control materials by spiking is incidental. A sample (the matrix) is fortified (spiked) with the analyte of interest for a variety of analytical and quality control purposes. While the spiking of multiple sample portions is discussed, the method of standard additions is not covered.1.3 This guide is intended for use in conjunction with the individual analytical test method that provides procedures for analysis of the analyte or component of interest. The test method is used to determine an analyte or component’s background level and, again after spiking, its now elevated level. Each test method typically provides procedures not only for samples, but also for calibration standards or analytical control solutions, or both. These procedures include preparation, handling, storage, preservation, and analysis techniques. These procedures are applicable by extension, using the analyst’s judgement on a case-by-case basis, to spiking solutions, and are not reiterated in this guide. See also Practice E200 for preparation and storage information.1.4 These procedures apply only to analytes that are soluble in water at the concentration of the spike plus any background material, or to analytes soluble in a solvent that is itself water-soluble. The system used in the later case must result in a homogeneous solution of analyte and sample. Meaningful recovery data cannot be obtained if an aqueous solution or homogenous suspension of the analyte of interest in the sample cannot be attained. These procedures may be applicable to microbiological preparations if the homogeneity of the suspension can be adequately maintained throughout the course of the analysis, for example, by mechanical agitation or stirring.1.5 Matrix spiking may be performed in the field or in the laboratory, depending on which part of the analytical process is to be tested. Field spiking tests the recovery of the overall process, including preservation and shipping of the sample. Laboratory spiking tests the laboratory process only. Spiking of sample extracts, concentrates, or dilutions will test only that portion of the process subsequent to addition of the spike.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.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