4.1 On application of the hydraulic fluid within the mechanical fluidic system, the fluid may become contaminated with acid and chloride ion. Mechanical shearing of the hydraulic fluid in the presence of the minute quantity of water and residual amount of organic solvents, used in cleaning, may initiate formation of acid and chloride ion. Measurements are desired to control and maintain the cleanliness and non-corrosiveness of the fluidic system.1.1 This practice covers the measurement of the pH and chloride ion of water extraction of aerospace hydraulic fluids.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This guide is general and intended as a planning guide. To satisfactorily monitor a specific site, an investigator must sometimes design specific installation structures or modify those given in this guide to meet the requirements of the site in question. Because of the dynamic nature of the sediment transport process, the extent to which characteristics such as mass concentration and particle-size distribution are accurately represented in the monitoring program depends on the type of equipment used and method of collection of the SSC samples used to calibrate the optical readings. Sediment concentration is highly variable in both time and space. Numerous samples must be collected and analyzed with proper equipment and standardized methods for the rating of the optical equipment at a particular site (see Guide D4411 and Practice D3977).5.2 All optical equipment have an upper limit for valid readings, beyond which the meter will not read properly, commonly referred to as “blacking out.” If upper range of SSC are expected to cause optical instrument black out, then some other means should be devised, such as automatic pumping samplers, to collect samples during this period. See Edwards and Glysson (1)3 and Glysson (2) for information on collection of suspended sediment samples using pumping samplers. It should be noted that other technologies, such as lasers and acoustic dopplers, are also being used to monitor SSC continuously.5.3 The user of this guide should realize that because different technologies and different models of the same technology of turbidity meters can produce significantly different outputs for the same environmental sample, only one manufacturer and model of the turbidity meter can be used to develop the relationship between the SSC and turbidity readings at a site. If a different manufacturer or a different model type of turbidity meter is used, a new relationship will need to be develop for the site.1.1 This guide covers the equipment and basic procedures for installation, operation, and calibration of optical equipment as a surrogate for the continuous determination of suspended-sediment concentration (SSC) in open channel flow.1.2 This guide emphasizes general principles for the application of optical measurements to be used to estimate suspended-sediment concentration (SSC) in water. Only in a few instances are step-by-step instructions given. Continuous monitoring is a field-based operation, methods and equipment are usually modified to suit local conditions. The modification process depends upon the operator skill and judgment.1.3 This guide covers the use of the output from an optical instrument, such as turbidity and suspended-solids meters, to record data that can be correlated with suspended-sediment concentration. It does not cover the process of collecting data for continuous turbidity record, which would require additional calibration of the turbidity readings to the mean turbidity of the measurement cross section. For the purposes of this method it is assumed that the dependent variable will be mean cross-sectional suspended-sediment concentration data.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 The pH of an adhesive may be a factor whereby the adherends or the adhesive itself may be adversely affected in time by the acidity or alkalinity.1.1 This test method covers determination of the hydrogen ion concentration (pH), acidity, or alkalinity, of organic adhesives in the cured dry film form. This test method is not designed to apply to pressure-sensitive adhesives.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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Steam distillation is a classical separation technique, useful for preparing extracts for analysis by gas chromatography GC/MS or GC/IR. Distillates are suitable for analysis according to Test Method E 1387 or Guide E 1618.The visible oily liquid extract can be used as a courtroom exhibit, unlike extracts produced by other separation procedures which are solutions rather than a neat liquid.This practice is not useful for the separation of water soluble ignitable liquids such as alcohols or ketones.Alternate separation and concentration methods are suggested if the concentration of flammable or combustible liquid residues is not detectable by odor.This is a destructive technique that should only be used when a representative portion of the sample can be reserved for reanalysis. Those portions of the sample subjected to this procedure may not be suitable for resampling. Consider using passive headspace concentration as described in Practice E 1412.1.1 This practice covers the procedure for separating visible quantities of water insoluble hydrocarbons from samples of fire debris.1.2 This practice is recommended only for samples which have a detectable odor of petroleum distillates when examined at room temperature.1.3 This practice can yield useful extracts by the application of a solvent to the distillation trap in the event that only small quantities of hydrocarbons are obtained.1.4 Alternate separation and concentration procedures are listed in the referenced documents.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.

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1.1 This test method covers a technique for field testing the concentration of aqueous urea-based diesel exhaust fluid (DEF) prescribed for use in diesel engines equipped with selective catalytic reduction technology and is not intended to circumvent or replace the more accurate determination of urea content by refractive index laboratory method, described in ISO 22241-2, Annex C.1.2 This test method is designed solely as a quantitative test to determine the concentration of urea in DEF and does not purport to determine the quality of DEF nor to detect trace or other contaminants therein. Biuret content of DEF creates a known bias in this test method. See section 9.2.1 for details.1.3 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.4 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 In this guide, the conditions, measurement apparatus, and procedures for measuring several characteristics of nanoparticle properties on three different instrument platforms using laser-amplified detection/power spectrum analysis (LAD/PSA) technology are described. This is a more recently developed technology, commercialized in 1990, than the older technology known as either photon correlation spectroscopy (PCS) or quasi-elastic light scattering (QLS)—those titles are interchangeable—developed first in 1961. Nanoparticle tracking analysis (NTA) is the most recent DLS technology to be commercialized. All three of these technologies fall under the broader category of DLS, based on the “dynamic” movement of the measured nanoparticles under Brownian motion.4.2 DLS in the lower end of the nanometre size range becomes progressively more difficult as the particle optical scattering coefficients drop sharply, reducing the scattered light intensity. The advantage of the heterodyne detection mode over the homodyne detection mode, especially at the low end of the nanometre range, will be explained.4.3 The LAD/PSA technology will be described and the major differences between it and the PCS-QLS and NTA technologies will be made clear. For thorough discussions of PCS-QLS, refer to Guide E2490, Test Method E3247, and ISO 22412 Annex Section A.1. For a thorough discussion of nanoparticle tracking analysis (NTA), refer to Guide E2834. For detailed information on laser-amplified detection/frequency power spectrum (LAD/FPS) technology, refer to ISO 22412 Annex Section A.2. General information on particle characterization practices can be found in Practice E1817, and nanotechnology terminology is given in Terminology E2456. Detailed information on sampling for particle characterization can be found in ISO 14488.1.1 The technology, laser-amplified detection/power spectrum analysis (LAD/PSA), is available in three different platforms, which will be designated as Platforms A, B, and C.1.1.1 Platform A—This is a solid-state probe configuration that serves as the optical bench in each of the platforms. It consists of an optical fiber coupler with a y-beam splitter that directs the scattered light signal from the nanoparticles at 180° back to a photodiode detector. The sensing end of the probe can be immersed in a suspension or positioned to measure one drop of a sample on top of the sensing surface.1.1.2 Platform B—The same probe is mounted in a case, positioned horizontally, to detect the signal from either a disposable or permanent cuvette.1.1.3 Platform C—Two probes are mounted in a case, horizontally, at opposite sides of a permanent sample cell. Both size distribution and zeta potential can be measured in this configuration.1.2 The laser beam travelling through the probe measuring the scattered light from the sample of nanoparticles, in all three platforms, is partially reflected back to the same photodiode detector, and the high optical power of the laser is added to the low optical power of the scattered light signal. The interference (mixing or beating) of those two signals is known as heterodyne beating. The resulting high-power detected signal provides the highest signal-to-noise ratio among dynamic light-scattering (DLS) technologies.1.3 This combined, amplified, optical signal is converted with a Fast Fourier transform (FFT) into a frequency power spectrum, then into a logarithmic power spectrum that is deconvolved into number and volume size distributions. The mean intensity, polydispersity, number and volume size distributions, concentration, and molecular weight can be reported in all platforms, plus zeta potential on Platform C.1.4 This technology is capable of measuring nanoparticles in a size range from 2.0 nanometres (nm) to 10 micrometres (µm), at concentrations in a suspending liquid medium up to 40 % cc/mL for all parameters given in 1.3.1.5 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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