5.1 The U.S. Environmental Protection Agency Regulations, 40 CFR 266, require that boilers, cement kilns, and other industrial furnaces utilizing waste-derived fuel adhere to specific guidelines in assessing potential metals emissions. A common approach for estimating potential emissions is performing total metals analysis on all feed stream materials. This practice describes a multi-stage microwave-assisted digestion procedure that solubilizes trace elements for spectroscopic analyses.1.1 This practice describes the multi-stage microwave digestion of typical industrial furnace feed stream materials using nitric, hydrofluoric, hydrochloric, and boric acids for the subsequent determination of trace metals.1.2 This practice has been used successfully on samples of coal, coke, cement raw feed materials, and waste-derived fuels composed primarily of waste paint-related material in preparation for measuring the following trace elements: Ag, As, Ba, Be, Cd, Cr, Hg, Pb, Sb, and Tl. This practice may be applicable to elements not listed above.1.3 This practice is also effective for other waste materials (for example, fly ash, foundry sand, alum process residue, cement kiln dust, etc.).1.4 The values stated in SI units are to be regarded as standard. Other units of measurement in parentheses in this standard are informational.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. Specific hazard statements are given in Section 8.1.6 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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4.1 This test method permits the determination of very low levels of chloride ion in engine coolants containing the common corrosion inhibitor, mercaptobenzothiazole, or related mercaptans, which would normally interfere with the titration by also forming insoluble silver salts with silver nitrate.1.1 This test method covers the determination of chloride ion in engine coolants in the range from 5 ppm to 200 ppm in the presence of up to 0.6 weight % mercaptobenzothiazole.1.2 Other materials that react with silver ion will interfere.1.3 Chloride in engine coolants containing an aryltriazole instead of mercaptobenzothiazole can be determined directly by this test method without pretreatment with hydrogen peroxide.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazards statements are given in Section 7.1.6 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 Trace elemental analysis is used to indicate the level of contamination of middle distillate fuels. Trace metals in turbine fuels can cause corrosion and deposition on turbine components at elevated temperatures. Some diesel fuels have specification limit requirements for trace metals to guard against engine deposits. Trace level copper in middle distillate aviation turbine fuel can significantly accelerate thermal instability of the fuel, leading to oxidation and production of detrimental insoluble deposits in the engine.5.2 Gas turbine fuel oil Specification D2880 provides recommended upper limits for five trace metals (calcium, lead, sodium, potassium, and vanadium). Military specification MIL-DTL-16884 for naval distillate fuel sets requirements for maximum concentrations of the same five metals. Both specifications designate Test Method D3605, an atomic absorption/flame emission method, for the quantitative analysis of four of the metals. Test Method D3605 does not cover potassium. This test method provides an alternative to Test Method D3605, covers potassium and a number of additional elements.5.3 There are several sources of multi-element contamination of naval distillate fuel. Sea water is pumped into the diesel fuel tanks (as ballast) to trim ships. Also, some of the oilers (fuel supply ships) have dirty tanks. Corrosion products come from unlined tanks, piping, pumps, and heat exchangers.1.1 This test method covers the determination of selected elements in middle distillate fuels by inductively coupled plasma atomic emission spectrometry (ICP-AES). The specific elements are listed in Table 1. The concentration range of this test method is approximately 0.1 mg/kg to 2.0 mg/kg. The test method may be used for concentrations outside of this range; however, the precision statements may not be applicable. Middle distillate fuels covered in this test method have all distillation fractions contained within the boiling range of 150 °C to 390 °C. This includes, but is not limited to, diesel fuels and aviation turbine fuels.1.2 This test method is not intended to analyze insoluble particulates. However, very small particulate matter (smaller than a micrometre) will be carried into the plasma and be included in the quantitative analysis.1.3 This test method may give a result that is higher than the true value if an analyte is present in the sample in a form which is sufficiently volatile. For example, hexamethyldisiloxane will generate a biased high result for silicon.1.4 The values stated in SI units are to be regarded as 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, 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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This method has been prepared to detect and quantitate nitrogen-containing compounds such as N-formylmorpholine (4-formylmorpholine, Chemical Abstract Service numbers (CAS) No. 250-37-6) or 1-methyl-2-pyrrolidinone (NMP) (CAS) No. 872-50-42 at a concentration of 1.0 mgN/kg or less in aromatic hydrocarbons used or produced in manufacturing processes. These nitrogen-containing compounds are undesirable in the finished aromatic products and may be the result of the aromatic extraction process. This test method may be used in setting specifications for determining the total nitrogen content in aromatic hydrocarbons. Note 1—Virtually all organic and inorganic nitrogen compounds will be detected by this technique. This technique will not detect diatomic nitrogen and it will produce an attenuated response when analyzing compounds (that is, s-triazine and azo compounds, etc.) that form nitrogen gas (N2) when decomposed. This test method requires the use of reduced pressure at the detector. Loss of vacuum or pressure fluctuations impact the sensitivity of the detector and the ability to determine nitrogen concentrations less than 1 mg/kg.1.1 This test method covers the determination of total nitrogen (organic and inorganic) in aromatic hydrocarbons, their derivatives and related chemicals. 1.2 This test method is applicable for samples containing nitrogen from 0.2 to 2 mgN/kg. For higher nitrogen concentrations refer to Test Method D 4629.1.2.1 The detector response of this technique within the specified scope of this test method is linear with nitrogen concentration.1.3 The following applies to all specified limits in this test method: for purposes of determining conformance with this test method, an observed value or a calculated value shall be rounded off "to the nearest unit" in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E 29.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are 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 hazard statements, see Section 9.

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5.1 Elemental constituents in potable water, receiving water, and wastewater need to be identified for support of effective pollution control programs. Currently, one of the most sensitive and practical means for measuring low concentrations of trace elements is by graphite furnace atomic absorption spectrophotometry. ICP-MS may also be appropriate but at a higher instrument cost. See Test Method D5673.1.1 This practice covers the general considerations for the quantitative determination of trace elements in water and wastewater by graphite furnace atomic absorption spectrophotometry. Furnace atomizers are a most useful means of extending detection limits; however, the practice should only be used at concentration levels below the optimum range of direct flame aspiration atomic absorption spectrophotometry. Because of differences between various makes and models of satisfactory instruments, no detailed operating instructions can be provided for each instrument. Instead, the analyst should follow the instructions provided by the manufacturer of a particular instrument.1.2 Wavelengths, estimated detection limits, and optimum concentration ranges are given in the individual methods. Ranges may be increased or decreased by varying the volume of sample injected or the instrumental settings or by the use of a secondary wavelength. Samples containing concentrations higher than those given in the optimum range may be diluted or analyzed by other techniques.1.3 This technique is generally not applicable to brines and seawater. Special techniques such as separation of the trace elements from the salt, careful temperature control through ramping techniques, or matrix modification may be useful for these samples.1.4 The analyst is encouraged to consult the literature as provided by the instrument manufacturer as well as various trade journals and scientific publications.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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.

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4.1 The anions fluoride, chloride, and sulfate have been identified as important contributors to corrosion of high pressure boilers, electric power turbines and their associated heat exchangers. Many electric power utilities attempt to reduce these contaminants in their boiler feed water to less than 1 μg/L.4.2 In the semiconductor manufacturing process these ions, among others, have been identified as a cause of low product yield and, thus, must be monitored and controlled to levels similar to those required by the electric power industry.4.3 Low molecular weight organic acids, such as acetate and formate, have been found in many steam generator feed waters and condensates. They are believed to come from the high temperature breakdown of organic matter found in boiler make up water. It is felt that these organic acids promote corrosion by lowering the pH of boiler waters and may even be corrosive themselves.4.4 Such low molecular weight organics may also be produced when ultraviolet light is used to produce bacteria-free water for semiconductor processing. Such polar organic contaminants are suspected of causing reduced semiconductor yields.4.5 Phosphates are commonly added to drum boilers in the low mg/L level to precipitate calcium and magnesium and thereby prevent scale formation. Ion chromatography can be used to monitor the concentration of such chemicals in boiler water, as well as detect unwanted carry-over into the steam.1.1 These test methods cover the determination of trace (μg/L) levels of fluoride, acetate, formate, chloride, phosphate, and sulfate in high purity water using ion chromatography in combination with sample preconcentration. Other anions, such as bromide, nitrite, nitrate, sulfite, and iodide can be determined by this method. However, since they are rarely present in significant concentrations in high purity water, they are not included in this test method. Two test methods are presented and their ranges of application, as determined by a collaborative study, are as follows:  Range Tested(μg/L Added) Limit of DetectionA(Single Operator)(μg/L) SectionsTest Method A:      7–16 Chloride 0–24  0.8   Phosphate 0–39  B   Sulfate 0–55  1.8  Test Method B:     17–24 Fluoride 0–14  0.7   Acetate 0–414 6.8   Formate 0–346 5.6  (A) Limit of detection is lowest measurable concentration not reportable as zero at 99 % level of confidence as per EPRI study as cited in Sections 16 and 24.(B) Insufficient data to calculate limit of detection.1.2 It is the user's responsibility to ensure the validity of these test methods for waters of untested matrices.1.3 The common practical range of Test Method A is as follows: chloride, 1 to 100 μg/L, phosphate, 3 to 100 μg/L, and sulfate, 2 to 100 μg/L.1.4 The common practical range of Test Method B is as follows: fluoride, 1 to 100 μg/L, acetate, 10 to 200 μg/L, and formate, 5 to 200 μg/L.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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.

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4.1 This test method is suitable for setting specifications on benzene and for use as an internal quality control tool where benzene is either produced or used in a manufacturing process.4.2 This test method was found applicable for determining thiophene in refined benzene conforming to the specifications described in Specification D2359 and may be applicable toward other grades of benzene if the user has taken the necessary precautions as described in the text.1.1 This test method covers the determination of thiophene in refined benzene in the range from 0.80 to 1.80 mg/kg for the Flame Photometric Detector (FPD), and from 0.14 to 2.61 mg/kg for the Pulsed Flame Photometric Detector (PFPD). For the PFPD, the minimum level of quantitation (LOQ) is 0.14 mg/kg and the minimum level of detection (LOD) is 0.04 mg/kg, as described in ASTM Research Report RR:D16-1038.2 The range of the test method may be extended by modifying the sample injection volume, split ratios, calibration range, or sample dilution with thiophene-free solvent.1.2 This test method has been found applicable to benzene characteristic of the type described in Specifications D2359 and D4734 and may be applicable to other types or grades of benzene only after the user has demonstrated that the procedure can completely resolve thiophene from the other organic contaminants contained in the sample.1.3 The following applies to all specified limits in this test method: for purposes of determining conformance to applicable specification using this test method, an observed value or a calculated value shall be rounded off “to the nearest unit” in the last right-hand digit used in expressing the specification limit in accordance with the rounding-off method of Practice E29.1.4 The values stated in SI units are to be regarded as 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 7.1.6 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 Low operating temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) require high purity hydrogen for maximum performance. The following are the reported effects (SAE TIR J2719) of the compounds determined by this test method.5.2 Carbon Dioxide (CO2), acts largely as a diluent; however, in the fuel cell environment, CO2 can be transformed into CO.5.3 Water (H2O), is an inert impurity, as it does not affect the function of a fuel cell stack; however, it provides a transport mechanism for water-soluble contaminants, such as Na+ or K+. In addition, it may form ice on valve internal surface at cold weather or react exothermally with metal hydride used as hydrogen fuel storage.5.4 Inert Gases (N2 and Ar), do not normally react with fuel cell components or fuel cell system and are considered diluents. Diluents can decrease fuel cell stack performance.5.5 Oxygen (O2), in low concentrations is considered an inert impurity, as it does not adversely affect the function of a fuel cell stack; however, it is a safety concern for vehicle on board fuel storage as it can react violently with hydrogen to generate water and heat.1.1 This test method describes a procedure primarily for the determination of carbon dioxide, argon, nitrogen, oxygen, and water in high pressure fuel cell grade hydrogen by gas chromatograph/mass spectrometer (GC/MS) with injection of sample at the same pressure as sample without pressure reduction, which is called “Jet Pulse Injection.” The procedures described in this method were designed to measure carbon dioxide at 0.5 micromole per mole (ppmv), Argon 1 ppmv, nitrogen 5 ppmv, oxygen 2 ppmv, and water 4 ppmv.1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.3 The mention of trade names in standard does not constitute endorsement or recommendation for use. Other manufacturers of equipment or equipment models can be used.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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Low operating temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) require high purity hydrogen for maximum material performance and lifetime. Sulfur compounds are present in many of the materials used in hydrogen production and small quantities typically remain after processing and purification. Part-per-billion concentrations of sulfur gases such as hydrogen sulfide (H2S), carbonyl sulfide (COS) and mercaptans diminish single fuel cell capacity.1.1 This test method describes a procedure primarily for the determination of hydrogen sulfide, carbonyl sulfide, methyl mercaptan, and carbon disulfide (Table 1) in hydrogen fuels for fuel cell vehicles (FCV) by gas chromatograph with sulfur chemiluminescence detection. The reporting limit is 0.02 ppbv (nanomole per mole as volume), based upon the analysis of a 500 mL hydrogen sample. The procedures described in this method were designed to satisfy sulfur contaminant determination requirements contained in SAE TIRJ2719 and the California Code of Regulations, CFR , Title 4, Division 9, Chapter 6, Article 8, Sections 4180 – 4181.1.2 This test method can be extended to other sulfur species in hydrogen fuel that are eluted through a chromatographic column.1.3 This test method can be modified to analyze all sulfur compounds present without chromatographic separation; thus, providing a total sulfur estimation without speciation (Appendix X1).1.4    If any new sulfur compounds need to be analyzed in hydrogen fuel, the calibration or spiking sulfur standards must include these new compounds after their method detection limit study. In addition, no co-elution is allowed in the chromatographic analysis of the calibration standard containing both the newly added and the existing sulfur target compounds. If necessary, the chromatographic conditions may be modified to achieve this goal.1.5 Although, primarily intended for determining sulfur in hydrogen used as a fuel for fuel cell or internal combustion engine powered vehicles, this test method can also be used to measure sulfur compounds in other gaseous fuels and gaseous matrices provided data quality objectives are satisfied.1.6 The values stated in SI units are standard. The values stated in inch-pound units are for information only.1.7 Mention of trade names in this standard does not constitute endorsement or recommendation for use. Other manufacturers of equipment or equipment models can be used.1.8 Alternative Detectors—This test method is written primarily for the use of sulfur chemiluminescent detectors but other detectors can be used provided they can detect hydrogen sulfide, carbonyl sulfide, methyl mercaptan, and carbon disulfide at 0.02 ppbv in hydrogen and meet data quality objectives for the intended use.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 and health practices and determine the applicability of regulatory limitations prior to use. For safety issues related to liquid nitrogen, refer to material safety data sheet (MSDS) from liquid nitrogen supplier.

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5.1 Fuel cell users have implicated trace impurities in feed gases as compromising the performance and lifespan of proton exchange membrane fuel cells (PEMFCs). PEMFCs may be damaged by the presence of some contaminants through poisoning of fuel cell electrode materials; therefore detection of these impurities at low concentrations is critical to fuel cell manufacturers and feed gas suppliers in order to support the facilities and infrastructure required for widespread applicability of fuel cells in transportation and energy production. With field-portable equipment, this test method can be used to quickly analyze hydrogen fuel for impurities at vehicle fueling stations or storage tanks used to supply stationary power plants. This test method can also be used by gas suppliers, customers, and regulatory agencies to certify hydrogen fuel quality.5.2 Users include hydrogen producers, gaseous fuel custody transfer stakeholders, fueling stations, fuel cell manufacturers, automotive manufacturers, regulators, and stationary fuel cell power plant operators.1.1 This test method employs an FTIR gas analysis system for the determination of trace impurities in gaseous hydrogen fuels relative to the hydrogen fuel quality limits described in SAE TIR J2719 (April 2008) or in hydrogen fuel quality standards from other governing bodies. This FTIR method is used to quantify gas phase concentrations of multiple target contaminants in hydrogen fuel either directly at the fueling station or on an extracted sample that is sent to be analyzed elsewhere. Multiple contaminants can be measured simultaneously as long as they are in the gaseous phase and absorb in the infrared wavelength region. The detection limits as well as specific target contaminants for this standard were selected based upon those set forth in SAE TIR J2719.1.2 This test method allows the tester to determine which specific contaminants for hydrogen fuel impurities that are in the gaseous phase and are active infrared absorbers which meet or exceed the detection limits set by SAE TIR J2719 for their particular FTIR instrument. Specific target contaminants include, but are not limited to, ammonia, carbon monoxide, carbon dioxide, formaldehyde, formic acid, methane, ethane, ethylene, propane, and water. This test method may be extended to other impurities provided that they are in the gaseous phase or can be vaporized and are active infrared absorbers.1.3 This test method is intended for analysis of hydrogen fuels used for fuel cell feed gases or for internal combustion engine fuels. This method may also be extended to the analysis of high purity hydrogen gas used for other applications including industrial applications, provided that target impurities and required limits are also identified.1.4 This test method can be used to analyze hydrogen fuel sampled directly at the point-of-use from fueling station nozzles or other feed gas sources. The sampling apparatus includes a pressure regulator and metering valve to provide an appropriate gas stream for direct analysis by the FTIR spectrometer.1.5 This test method can also be used to analyze samples captured in storage vessels from point-of-use or other sources. Analysis of the stored samples can be performed either in a mobile laboratory near the sample source or in a standard analytical laboratory.1.6 A test plan should be prepared that includes (1) the specific impurity species to be measured, (2) the concentration limits for each impurity species, and (3) the determination of the minimum detectable concentration for each impurity species as measured on the apparatus before testing.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7.1 Exception—All values are based upon common terms used in the industry of those particular values and when not consistent with SI units, the appropriate SI unit will be included in parentheses after the common value usage (4.4, 7.8, 7.9, 10.5, and 11.6).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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High water concentrations can have a detrimental effect on many uses of aromatic hydrocarbons, their mixtures and related compounds. Water can inhibit desired reactions when aromatic hydrocarbons, their mixtures and related compounds are used in formulations and chemical processes. Water can cause corrosion problems and detrimental effects during the manufacture and processing of aromatic hydrocarbons, their mixtures and related compounds.1.1 This test method describes the use of the Coulometric Karl Fischer (KF) titration for the determination of water in aromatic hydrocarbons and their mixtures, derivatives and related chemicals. 1.2 This test method is applicable to samples with water concentrations from 10 to 400 mg/kg. 1.3 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 E 29. 1.4 Values stated in SI units are to be regarded as the standard. The preferred units are milligrams per kilogram (mg/kg). 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. For a specific hazard statement see Section 8.

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5.1 This test method is useful for the determination of elemental concentrations in the range of approximately 0.1 µgg-1 to 10 percent (%) (See Table X1.1) in soda-lime glass samples (7 and 8). A standard test method can aid in the interchange of data between laboratories and in the creation and use of glass databases.5.2 The determination of elemental concentrations in glass provides high discriminating value in the forensic comparison of glass fragments.5.3 This test method produces minimal destruction of the sample. Microscopic craters of 50 µm to 100 µm in diameter by 80 µm to 150 µm deep are left in the glass fragment after analysis. The mass removed per replicate is approximately 0.4 µg to 3 µg (6).5.4 Appropriate sampling techniques shall be used to account for natural heterogeneity of the materials at a microscopic scale.5.5 The precision, bias, and limits of detection of the method (for each element measured) shall be established during validation of the method. The measurement uncertainty of any concentration value used for a comparison shall be recorded with the concentration.5.6 Acid digestion of glass followed by either Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) can also be used for trace elemental analysis of glass, and offer similar detection levels and the ability for quantitative analysis. However, these methods are destructive, and require larger sample sizes and more sample preparation (Test Method E2330).5.7 Micro X-Ray Fluorescence (µ-XRF) uses comparable sample sizes to those used for LA-ICP-MS with the advantage of being non-destructive of the sample. Some of the drawbacks of µ-XRF include lower sensitivity and precision, and longer analysis time (Test Method E2926).5.8 Scanning Electron Microscopy with Energy Dispersive Spectrometry (SEM-EDS) is also available for elemental analysis, but it is of limited use for forensic glass source discrimination due to poor detection limits for higher atomic number elements present in glass at trace concentration levels. However, distinguishing between sources having similar RIs and densities is sometimes possible.1.1 This test method covers a procedure for the quantitative elemental analysis of the following seventeen elements: lithium (Li), magnesium (Mg), aluminum (Al), potassium (K), calcium (Ca), iron (Fe), titanium (Ti), manganese (Mn), rubidium (Rb), strontium (Sr), zirconium (Zr), barium (Ba), lanthanum (La), cerium (Ce), neodymium (Nd), hafnium (Hf) and lead (Pb) through the use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for the forensic comparison of glass fragments. The potential of these elements to provide the best discrimination among different sources of soda-lime glasses has been published elsewhere (1-5).2 Silicon (Si) is also monitored for use as a normalization standard. Additional elements may be added as needed, for example, tin (Sn) can be used to monitor the orientation of float glass fragments.1.2 The method only consumes approximately 0.4 µg to 3 µg of glass per replicate and is suitable for the analysis of full thickness samples as well as irregularly shaped fragments as small as 0.1 mm by 0.1 mm by 0.2 mm (6) in dimension. The concentrations of the elements listed above range from the low parts per million (µgg-1) to percent (%) levels in soda-lime glass, the most common type encountered in forensic cases. This standard method can be applied for the quantitative analysis of other glass types; however, some modifications in the reference standard glasses and the element menu may be required.1.3 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917), and demonstrated proficiency to perform forensic casework.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, 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 Commercial trace detectors are used by first responders, security screeners, the military, and law enforcement to detect and identify explosive threats and drugs of interest quickly. These trace detectors typically operate by detecting chemical agents in residues and particles sampled from surfaces and can have detection limits for some compounds extending below 1 ng. A trace detector is set to alarm when its response to any target analyte exceeds a programmed threshold level for that analyte. Factory settings of such levels typically balance sensitivity and selectivity assuming standard operating and deployment conditions.5.2 The LOD for a substance is commonly accepted as the smallest amount of that substance that can be reliably detected in a given type of medium by a specific measurement process (2). The analytical signal from this amount shall be high enough above ambient background variation to give statistical confidence that the signal is real. Methods for determining nominal LOD values are well known but pitfalls exist in specific applications. Vendors of trace detectors often report detection limits for only a single compound without defining the meaning of terms or reference to the method of determination.NOTE 2: There are several different “detection limits” that can be determined for analytical procedures. These include the minimum detectable value, the instrument detection limit, the method detection limit, the limit of recognition, the limit of quantitation, and the minimum consistently detectable amount. Even when the same terminology is used, there can be differences in the LOD according to nuances in the definition used, the assumed response model, and the type of noise contributing to the measurement.5.3 When deployed, the individual performance of a trace detector (for example, realistic LODs) is influenced by: (1) manufacturing differences, history, and maintenance; (2) operating configurations (for example, thermal desorption temperature, analyzer temperature, and type of swab); and (3) environmental conditions (for example, ambient humidity and temperature and chemical background). As a result, realistic LOD values for a trace detector may be poorly estimated by the factory specifications. These fundamental measures of performance are critically important for assessing the ability of an instrument to detect trace levels of particular compounds in a particular setting, so a reliable and accessible method is needed to estimate realistic LOD values, especially in the field.5.4 Technical Challenges and Pitfalls to the Estimation of LOD Values in Trace Detectors and the Setting of Optimal Alarm Thresholds: 5.4.1 —The U.S. Department of Justice lists over 230 explosive materials and over 270 controlled drugs having a high potential for abuse.4 There are many technologies used for trace detection, and instrument manufacturers design their systems and balance operating conditions to provide detection capabilities across as many analytes as possible. However, a very limited subset of analytes is normally used to test and verify detector performance. Therefore, default operating conditions and alarm thresholds may not be optimally set to detect reliably certain compounds deemed important in particular scenarios.5.4.2 Environment—Ambient conditions and chemical background vary with the deployment location, which would influence response sensitivities and LOD values.5.4.3 Risk Tolerance and Balance—Values of alpha risk (false positive probability of process blanks) and beta risk (false nondetection probability of analytes at the detection limit) should be balanced and set according to security priorities (for example, alert level, probable threat compounds, throughput requirements, human factors, and risk tolerance). The default risk balance in a trace detector may not be adequate for the deployment situation.5.4.4 Signal Variability (Heteroskedasticity)—The variance in instrument response may not be consistent across analyte mass levels introduced into the trace detector. In ion mobility spectrometry (IMS)-based technologies, the physicochemical mechanisms underlying atmospheric pressure ionization (with a finite number of available reactant ions) and ion mobility separation may be non-uniform across the response regions. Typical methods of LOD estimation usually assume constant variance.5.4.5 Proprietary Signal Processing—Typical LOD determinations assume Gaussian distributions and use background variation as an important parameter. Unfortunately, alarm decisions in trace detectors are rarely based on raw measurement signals; rather, proprietary algorithms are used to process the raw measurements. This processing may attempt to minimize alpha risk by truncating or dampening background signals, so background signals may be absent or the true distribution in these processed signals may be non-Gaussian, confounding the calculation of an accurate LOD.5.4.6 Multivariate Considerations—To improve selectivity and decrease alpha risk, alarm decisions in trace detectors may be based on multiple-peak responses rather than a single-peak amplitude measurement. Efforts to recognize and quantify unique ion fragmentation patterns across both the thermal desorption and drift-time domains are being developed for next-generation detectors.5.4.7 Diversity of Technologies—The wide variety of trace detectors and technologies on the market and those under development challenge general response models for accurate estimation of LOD.5.4.8 Security—LOD values for explosives in trace detectors may not be openly published because of security and classification issues.1.1 In harmony with the Joint Committee for Guides in Metrology (JCGM) and detection concepts of the International Union of Pure and Applied Chemistry (IUPAC) (1, 2)2, this test method uses a series of replicated measurements of an analyte at dosage levels giving instrumental responses that bracket the critical value, a truncated normal distribution model, and confidence bounds to establish a standard for estimating practical and statistically robust limits of detection.NOTE 1: Other standards are available that evaluate the general performance of detection technologies for various analytes in complex matrices (for example, Practice E2520).1.2 Here, the limit of detection (LOD90) for a compound is defined to be the lowest mass of that compound deposited on a sampling swab for which there is 90 % confidence that a single measurement in a particular trace detector will have a true detection probability of at least 90 % and a true nondetection probability of at least 90 % when measuring a process blank sample.1.3 This particular test method was chosen on the basis of reliability, practicability, and comprehensiveness across tested trace detectors, analytes, and deployment conditions. The calculations involved in this test method are published elsewhere (3), and are performed through an interactive web-based calculator available on the National Institute of Standards and Technology (NIST) site: https://www-s.nist.gov/loda.1.4 Intended Users—Trace detector developers and manufacturers, vendors, testing laboratories, and agencies responsible for public safety and enabling effective deterrents to terrorism.1.5 While this test method may be applied to any detection technology that produces numerical output, the method is especially applicable to measurement systems influenced by heterogeneous error sources that lead to non-linear and heteroskedastic dose/response relationships and truncated or censored response distributions at low analyte levels. The procedures have been tested using explosive and drug compounds in trace detectors based on ion mobility spectrometry, gas chromatography, and mass spectrometry (4). Compounds are deposited as liquid solutions on swabs and dried before use. Background interferences introduced to the test samples were representative of a variety of conditions expected during deployment, but these conditions were not intended as comprehensive in representing all possible scenarios. The user should be aware of the possibility that untested scenarios may lead to failure in the estimation of a reliable LOD90 value.1.6 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.7 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. Some specific hazards statements are given in Section 8 on Hazards.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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5.1 This test method is useful for the analysis of total uranium in water following wet-ashing, as required, due to impurities or suspended materials in the water.1.1 This test method covers the determination of total uranium, by mass concentration, in water within the calibrated range of the instrument, 0.1 μg/L or greater. Samples with uranium mass concentrations above the laser phosphorimeter dynamic range are diluted to bring the concentration to a measurable level.1.2 This test method was used successfully with reagent water. It is the user’s responsibility to ensure the validity of this test method for waters of untested matrices.1.3 The values stated in SI units are to be regarded as the 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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4.1 Accurate gas chromatographic determination of trace levels of thiophene in benzene involves special analytical problems because of the difficulties of trace level analysis. These problems arise from the low concentration levels that need to be measured, the type of column and detector needed for analysis, and the potential interference from the benzene matrix.4.2 This test method was found applicable for determining thiophene in refined benzene conforming to the specifications described in Specifications D2359, D4734, and D5871 and may be applicable toward other grades of benzene if the user has taken the necessary precautions as described in the text.4.3 This test method was developed as an alternative technique to Test Method D4735.1.1 This test method covers the determination of thiophene in refined benzene using gas chromatography and sulfur selective detection. The test method is applicable to the determination of thiophene at levels of 0.02 to 2.18 mg thiophene per kg in benzene (mg/kg) on the AED, 0.03 to 1.87 mg/kg on the PFPD, and 0.03 to 2.11 mg/kg on the SCD. The range of the test method may be extended by modifying the sample injection volume, split ratios, calibration range, or sample dilution with thiophene-free solvent.1.2 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 E29.1.3 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. For specific hazard statements, see Section 7.1.5 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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