4.1 The composition and sequential structure of alginate determines the functionality of alginate in an application. For instance, the gelling properties of an alginate are highly dependent upon the monomer composition and sequential structure of the polymer. Gel strength will depend upon the guluronic acid content (FG) and also the average number of consecutive guluronate moieties in G-block structures (NG>1).4.2 Chemical composition and sequential structure of alginate can be determined by 1H- and 13C-nuclear magnetic resonance spectroscopy (NMR). A general description of NMR can be found in <761> of the USP 35-NF30. The NMR methodology and assignments are based on data published by Grasdalen et al. (1979, 1981, 1983).4, 5, 6 The NMR technique has made it possible to determine the monad frequencies FM (fraction of mannuronate units) and FG (fraction of guluronate units), the four nearest neighboring (diad) frequencies FGG, FMG, FGM, FMM, and the eight next nearest neighboring (triad) frequencies FGGG, FGGM, FMGG, FMGM, FMMM, FMMG, FGMM, FGMG. Knowledge of these frequencies enables number averages of block lengths to be calculated. NG is the number average length of G-blocks, and NG>1 is the number average length of G-blocks from which singlets (-MGM-) have been excluded. Similarly, NM is the number average length of M-blocks, and NM>1 is the number average length of M-blocks from which singlets (-GMG-) have been excluded. 13C NMR must be used to determine the M-centered triads and NM>1. This test method describes only the 1H NMR analysis of alginate. Alginate can be well characterized by determining FG and NG>1.4.3 In order to obtain well-resolved NMR spectra, it is necessary to reduce the viscosity and increase the mobility of the molecules by depolymerization of alginate to a degree of polymerization of about 20 to 50. Acid hydrolysis is used to depolymerize the alginate samples. Freeze-drying, followed by dissolution in 99 % D2O, and another freeze-drying before dissolution in 99.9 % D2O yields samples with low 1H2O content. TTHA is used as a chelator to prevent traces of divalent cations to interact with alginate. While TTHA is a more effective chelator, other agents such as EDTA and citrate may be used. Such interactions may lead to line broadening and selective loss of signal intensity.4.4 Samples are analyzed at a temperature of 80 ± 1°C. Elevated sample temperature contributes to reducing sample viscosity and repositions the proton signal of residual water to an area outside that of interest.1.1 This test method covers the determination of the composition and monomer sequence of alginate intended for use in biomedical and pharmaceutical applications as well as in Tissue Engineered Medical Products (TEMPs) by high-resolution proton NMR (1H NMR). A guide for the characterization of alginate has been published as Guide F2064.1.2 Alginate, a linear polymer composed of β-D-mannuronate (M) and its C-5 epimer α-L-guluronate (G) linked by β-(1—>4) glycosidic bonds, is characterized by calculating parameters such as mannuronate/guluronate (M/G) ratio, guluronic acid content (G-content), and average length of blocks of consecutive G monomers (that is, NG>1 ). Knowledge of these parameters is important for an understanding of the functionality of alginate in TEMP formulations and applications. This test method will assist end users in choosing the correct alginate for their particular application. Alginate may have utility as a scaffold or matrix material for TEMPs, in cell and tissue encapsulation applications, and in drug delivery formulations.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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 The degree of deacetylation of chitosan salts is an important characterization parameter since the charge density of the chitosan molecule is responsible for potential biological and functional effects.4.2 The degree of deacetylation (% DDA) of water-soluble chitosan salts can be determined by 1H nuclear magnetic resonance spectroscopy (1H NMR). Several workers have reported on the NMR determination of chemical composition and sequential arrangement of monomer units in chitin and chitosan. The test method described is primarily based on the work of Vårum et al. (1991),5 which represents the first publication on routine determination of chemical composition in chitosans by solution state 1H NMR spectroscopy. This test method is applicable for determining the % DDA of chitosan chloride and chitosan glutamate salts. It is a simple, rapid, and suitable method for routine use. Quantitative 1H NMR spectroscopy reports directly on the relative concentration of chemically distinct protons in the sample, consequently, no assumptions, calibration curves or calculations other than determination of relative signal intensity ratios are necessary.4.3 In order to obtain well-resolved NMR spectra, depolymerization of chitosans to a number average degree of polymerization (DPn) of ~15 to 30 is required. This reduces the viscosity and increases the mobility of the molecules. Although there are several options for depolymerization of chitosans, the most convenient procedure is that of nitrous acid degradation in deuterated water. The reaction is selective, stoichiometric with respect to GlcN, rapid, and easily controlled (Allan & Peyron, 1995).6 The reaction selectively cleaves after a GlcN-residue, transforming it into 2,5-anhydro-D-mannose (chitose), consequently, depletion of GlcN after depolymerization is expected. On the other hand, the chitose unit displays characteristic 1H NMR signals the intensity of which may be estimated and utilized in the calculation of % DDA, eliminating the need for correction factors. Using the intensity of the chitose signals, the number average degree of polymerization can easily be calculated as a control of the depolymerization.4.4 Samples are equilibrated and analyzed at a temperature of 90 ± 1°C. Elevated sample temperature contributes to reducing sample viscosity and repositions the proton signal of residual water to an area outside that of interest. While samples are not stored at 90°C but only analyzed at this elevated temperature, the NMR tubes should be sealed with a stopper to avoid any evaporation. At a sample pH* of 3.8-4.3 (see 6.1.5 below), artifactual deacetylation of the sample does not occur during the short equilibration and analysis time.4.5 A general description of NMR can be found in <761> of the USP 35-NF30.1.1 This test method covers the determination of the degree of deacetylation in chitosan and chitosan salts intended for use in biomedical and pharmaceutical applications as well as in Tissue Engineered Medical Products (TEMPs) by high-resolution proton NMR (1H NMR). A guide for the characterization of chitosan salts has been published as Guide F2103.1.2 The test method is applicable for determining the degree of deacetylation (% DDA) of chitosan chloride and chitosan glutamate salts and is valid for % DDA values from 50 up to and including 99. It is simple, rapid, and suitable for routine use. Knowledge of the degree of deacetylation is important for an understanding of the functionality of chitosan salts in TEMP formulations and applications. This test method will assist end users in choosing the correct chitosan for their particular application. Chitosan salts may have utility in drug delivery applications, as scaffold or matrix material, and in cell and tissue encapsulation applications.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Performance properties are dependent on the number and type of short chain branches. This test method permits measurement of these branches for ethylene copolymers with propylene, butene-1, hexene-1, octene-1, and 4-methylpentene-1.1.1 This test method determines the molar composition of copolymers prepared from ethylene (ethene) and a second alkene-1 monomer. This second monomer can include propene, butene-1, hexene-1, octene-1, and 4-methylpentene-1.1.2 Calculations of this test method are valid for products containing units EEXEE, EXEXE, EXXE, EXXXE, and of course EEE where E equals ethene and X equals alkene-1. Copolymers containing a considerable number of alkene-1 blocks (such as, longer blocks than XXX) are outside the scope of this test method.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. See Section 8 for a specific hazard statement.NOTE 1: There is no known ISO equivalent to this standard.

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5.1 This test method may be used for material development, characterization, design data generation, and quality control purposes. It is specifically appropriate for determining the modulus of advanced ceramics that are elastic, homogeneous, and isotropic.5.1.1 This test method is nondestructive in nature. Only minute stresses are applied to the specimen, thus minimizing the possibility of fracture.5.1.2 The period of time during which measurement stress is applied and removed is of the order of hundreds of microseconds. With this test method it is feasible to perform measurements at high temperatures, where delayed elastic and creep effects would invalidate modulus measurements calculated from static loading.5.2 This test method has advantages in certain respects over the use of static loading systems for measuring moduli in advanced ceramics. It is nondestructive in nature and can be used for specimens prepared for other tests. Specimens are subjected to minute strains; hence, the moduli are measured at or near the origin of the stress-strain curve with the minimum possibility of fracture. The period of time during which measurement stress is applied and removed is of the order of hundreds of microseconds. With this test method it is feasible to perform measurements at high temperatures, where delayed elastic and creep effects would invalidate modulus measurements calculated from static loading.5.3 The sonic resonant frequency technique can also be used as a nondestructive evaluation tool for detecting and screening defects (cracks, voids, porosity, density variations) in ceramic parts. These defects may change the elastic response and the observed resonant frequency of the test specimen. Guide E2001 describes a procedure for detecting such defects in metallic and nonmetallic parts using the resonant frequency method.5.4 Modification of this test method for use in quality control is possible. A range of acceptable resonant frequencies is determined for a specimen with a particular geometry and mass. Any specimen with a frequency response falling outside this frequency range is rejected. The actual modulus of each specimen need not be determined as long as the limits of the selected frequency range are known to include the resonant frequency that the specimen must possess if its geometry and mass are within specified tolerances.1.1 This test method covers the determination of the dynamic elastic properties of advanced ceramics. Specimens of these materials possess specific mechanical resonant frequencies that are determined by the elastic modulus, mass, and geometry of the test specimen. Therefore, the dynamic elastic properties of a material can be computed if the geometry, mass, and mechanical resonant frequencies of a suitable rectangular or cylindrical test specimen of that material can be measured. The resonant frequencies in flexure and torsion are measured by mechanical excitation of vibrations of the test specimen in a suspended mode (Section 4 and Figs. 1 and 4). Dynamic Young’s modulus is determined using the resonant frequency in the flexural mode of vibration. The dynamic shear modulus, or modulus of rigidity, is found using torsional resonant vibrations. Dynamic Young’s modulus and dynamic shear modulus are used to compute Poisson’s ratio.1.2 This test method is specifically appropriate for advanced ceramics that are elastic, homogeneous, and isotropic (1).2 Advanced ceramics of a composite character (particulate, whisker, or fiber reinforced) may be tested by this test method with the understanding that the character (volume fraction, size, morphology, distribution, orientation, elastic properties, and interfacial bonding) of the reinforcement in the test specimen will have a direct effect on the elastic properties. These reinforcement effects must be considered in interpreting the test results for composites. This test method is not satisfactory for specimens that have cracks or voids that are major discontinuities in the specimen. Neither is the test method satisfactory when these materials cannot be fabricated in a uniform rectangular or circular cross-section.1.3 A high-temperature furnace and cryogenic cabinet are described for measuring the dynamic elastic moduli as a function of temperature from −195 to 1200 °C.1.4 There are material-specific ASTM standards that cover the determination of resonance frequencies and elastic properties of specific materials by sonic resonance or by impulse excitation of vibration. Test Methods C215, C623, C747, C848, C1259, E1875, and E1876 may differ from this test method in several areas (for example: sample size, dimensional tolerances, sample preparation, calculation details, etc.). The testing of those materials should be done in compliance with the appropriate material-specific standards. Where possible, the procedures, sample specifications, and calculations in this standard are consistent with the other test methods.1.5 The values stated in SI units are to be regarded as the standard. The non-SI values given in parentheses are for information only and are not considered 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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4.1 Tissue-engineered cartilage is prepared by seeding stem cells or chondrocytes in a three-dimensional biodegradable scaffold under controlled growth conditions. It is expected that the cells will differentiate towards chondrogenic lineage and produce an ample amount of cartilage extracellular matrix proteins, proteoglycans, and collagen type-II. Longitudinal assessment is needed weekly for the first few weeks in vitro and monthly at a later stage in vivo to determine the growth rate of tissue-engineered cartilage. Traditional testing methods such as histological staining, mechanical testing, and qPCR are invasive, destructive, and cannot be performed in vivo after the transplantation of engineered tissue as a regenerative treatment. In the regenerative medicine of cartilage, it is important to evaluate whether the implanted tissue regenerates as an articular cartilage over time. MRI is the only available non-invasive imaging modality that is utilized for post-operative monitoring and assessment of cartilage regeneration in clinics. Therefore, it is important to evaluate tissue-engineered cartilage using MRI at the preclinical stage as well.4.7.1 The change in calculated relaxation rate, R2(ECM), using Eq 1 have been found to be positively correlated with tissue growth (3, 6).1.1 This standard is intended as a standard test method for engineered cartilage tissue growth evaluation using MRI.1.2 This standard is intended for use in the development of tissue engineering regenerative medical products for cartilage damages, such as in knee, hip, or shoulder joints.1.3 This standard has been prepared for evaluation of engineered cartilage tissue growth at the preclinical stage and summarizes results from tissue growth evaluation of tissue-engineered cartilage in a few notable cases using water spin-spin relaxation time, T2, in vitro and in vivo in small animal models.1.4 This standard uses the change in mean T2 values as a function of growth time to evaluate the tissue growth of engineered cartilage.1.5 This standard provides a method to remove the scaffold contribution to the tissue growth evaluation.1.6 Information in this standard is intended to be applicable to most porous natural and synthetic polymers used as a scaffold in engineered cartilage, such as alginate, agarose, collagen, chitosan, and poly-lactic-co-glycolic acid (PLGA). However, some materials (both synthetic and natural) may require unique or varied methods of MRI evaluation that are not covered in this test method.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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5.1 PCRT Applications and Capabilities—PCRT PTI examination has been applied successfully to a wide range of parts in manufacturing and maintenance environments. Examples of manufacturing processes, repair processes, and in-service damage mechanisms evaluated with PTI are discussed in 1.1. PCRT has been shown to provide cost effective and accurate PTI-based NDT, process monitoring, and life monitoring in many industries including automotive, aerospace, and power generation. Examples of successful applications currently employed in commercial use include, but are not limited to:(1) Heat treatment operations:(a) Aerospace gas turbine engine components (blades, vanes, disks)(b) Additively manufactured components(c) Steel mechanical components(d) Industrial gas turbine blades(2) Induction hardening and carburization (both case-hardened and through-hardened parts):(a) Gears(b) Ballnuts(3) Hot Isostatic Pressing (HIP):(a) Gas turbine engine components (blades, vanes, disks)(b) Additively manufactured components(4) Shot peening:(a) Steel mechanical components(5) In-service thermal history, aging, creep damage, fatigue:(a) Gas turbine engine components (blades, vanes, disks)(b) Industrial gas turbine blades(c) Aircraft landing gear wheels(6) Maintenance repair/rejuvenation processes:(a) Gas turbine engine components (blades, vanes, disks)(b) Industrial gas turbine blades(c) Aircraft landing gear wheels.5.2 General Approach and Equipment Requirements for PCRT via Swept Sine Input: 5.2.1 PCRT systems comprise hardware and software capable of inducing vibrations, recording the component response to the induced vibrations, and analyzing the data collected. Inputting a swept sine wave into the part has proven to be an effective means of introducing mechanical vibration and can be achieved with a high-quality signal generator coupled with an appropriate active transducer in physical contact with the part. Collection of the part’s resonance response is achieved by recording the signal received by an appropriate passive vibration transducer. The software required to analyze the available data may include a variety of suitable statistical analysis and pattern recognition tools. Measurement accuracy and repeatability are extremely important to the application of PCRT.5.2.2 Hardware Requirements—A swept sine wave signal generator and response measurement system operating over the desired frequency range of the test part are required with accuracy better than 0.002 %. The signal generator should be calibrated to applicable industry standards. Transducers must be operable over same frequency range. Three transducers are typically used; one Drive transducer and two Receive transducers. Transducers typically operate in a dry environment, providing direct contact coupling to the part under examination. However, noncontacting response methods can operate suitably when parts are wet or oil-coated. Other than fixturing and transducer contact, no other contact with the part is allowed as these mechanical forces dampen certain vibrations. For optimal examination, parts should be placed precisely on the transducers (generally, ±0.062 in. (1.6 mm) in each axis provides acceptable results). The examination nest and cabling shall isolate the Drive from Receive signals and ground returns, so as to not produce (mechanical or electrical) cross talk between channels. Excessive external vibration or audible noise, or both, will compromise the measurements.5.3 Constraints and Limitations: 5.3.1 PCRT cannot separate parts based on visually detectable anomalies that do not affect the structural integrity of the part. It may be necessary to provide additional visual inspection of parts to identify these indications.5.3.2 Excessive variation in part geometry or base material properties may limit the sensitivity of PCRT PTI examination.5.3.3 A direct measurement of a single geometric dimension of a region undergoing a material state change, such as the case depth (in centimeters or inches) of an induction hardened region, is generally not possible with PCRT PTI. The frequency changes are dependent on the total volumetric effect of the process that causes the material state change. With accurately trained acceptability limits, however, PCRT PTI is very effective at screening populations of components for acceptable and unacceptable processing.5.3.4 PCRT will only work with stiff objects that provide resonances whose peak quality factor (Q) values are greater than 500. Non-rigid materials or very thin-walled parts will not yield useful Q values.5.3.5 While PCRT can be applied to painted and coated parts in many cases, the presence of some surface coatings such as vibration absorbing materials and heavy oil layers may limit or preclude the application of PCRT.5.3.6 While PCRT PTI examination can be applied to parts over a wide range of temperatures, it cannot be applied to parts that are rapidly changing temperature. The part temperature should be stabilized before collecting resonance data.5.3.7 Misclassified parts in the teaching set, along with the presence of unknown anomalies in the teaching set, can significantly reduce the accuracy and sensitivity of PCRT.1.1 This practice covers a general procedure for using the Process Compensated Resonance Testing (PCRT) via swept sine input method to perform Part-to-Itself (PTI) examination on populations of newly manufactured and in-service parts. PCRT detects resonance pattern differences in metallic and non-metallic parts. Practice E2534 for Defect Detection with PCRT and Practice E3081 for Outlier Screening with PCRT cover the development and application of PCRT sorting modules that inspect a part at a single point in time. These methods use the resonance frequency spectra recorded from test parts and perform different statistical analyses to compare test parts to reference populations. These comparisons include, and must compensate for, the normal geometric, material, and processing variations present in any population of parts. In many applications, however, the user may need to evaluate the effects of a single processing step or in-service load in isolation from other sources of variation. For example, a manufacturer may want to perform process monitoring and control on a heat treatment or hardening process. A maintainer may want to evaluate the effect of service cycles in an engine. A PCRT PTI examination measures the resonance frequency spectrum of a part at two points in time, such as before and after a manufacturing process step, and calculates the change in resonance frequencies to evaluate the effect of the intervening process. Control limits can be set on the frequency change to field a PTI PASS/FAIL inspection capability. The limits may be based on training populations of parts with acceptable and unacceptable levels of change, model predictions of the effects of part changes, or criteria derived from process control practices. Manufacturing processes and in-service loads that can be evaluated with a PCRT PTI inspection include, but are not limited to heat treatment, hot isostatic pressing (HIP), shot peening, induction hardening, carburization, coating, thermal history changes, residual stress changes, creep, plastic deformation, corrosion, and fatigue. This practice is intended for use with instruments capable of exciting, measuring, recording, and analyzing multiple, whole body, mechanical vibration resonance frequencies in acoustic or ultrasonic frequency ranges, or both.1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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 Aromatic content is a key characteristic of hydrocarbon oils and can affect a variety of properties of the oil including its boiling range, viscosity, stability, and compatibility of the oil with polymers.5.2 Existing methods for estimating aromatic contents use physical measurements, such as refractive index, density, and number average molecular weight (see Test Method D3238) or infrared absorbance4 and often depend on the availability of suitable standards. These NMR procedures do not require standards of known aromatic hydrogen or aromatic carbon contents and are applicable to a wide range of hydrocarbon oils that are completely soluble in chloroform at ambient temperature.5.3 The aromatic hydrogen and aromatic carbon contents determined by this test method can be used to evaluate changes in aromatic contents of hydrocarbon oils due to changes in processing conditions and to develop processing models in which the aromatic content of the hydrocarbon oil is a key processing indicator.1.1 This test method covers the determination of the aromatic hydrogen content (Procedures A and B) and aromatic carbon content (Procedure C) of hydrocarbon oils using high-resolution nuclear magnetic resonance (NMR) spectrometers. Applicable samples include kerosenes, gas oils, mineral oils, lubricating oils, coal liquids, and other distillates that are completely soluble in chloroform at ambient temperature. For pulse Fourier transform (FT) spectrometers, the detection limit is typically 0.1 mol % aromatic hydrogen atoms and 0.5 mol % aromatic carbon atoms. For continuous wave (CW) spectrometers, which are suitable for measuring aromatic hydrogen contents only, the detection limit is considerably higher and typically 0.5 mol % aromatic hydrogen atoms.1.2 The reported units are mole percent aromatic hydrogen atoms and mole percent aromatic carbon atoms.1.3 This test method is not applicable to samples containing more than 1 mass % olefinic or phenolic compounds.1.4 This test method does not cover the determination of the percentage mass of aromatic compounds in oils since NMR signals from both saturated hydrocarbons and aliphatic substituents on aromatic ring compounds appear in the same chemical shift region. For the determination of mass or volume percent aromatics in hydrocarbon oils, chromatographic, or mass spectrometry methods can be used.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 problems, 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 statements are given in 7.2 and 7.3.

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5.1 PCRT Applications and Capabilities—PCRT has been applied successfully to a wide range of NDT applications in the manufacture and maintenance of metallic and non-metallic parts. Examples of anomalies detected are discussed in 1.1. PCRT has been shown to provide cost effective and accurate NDT solutions in many industries including automotive, aerospace, and power generation. Examples of successful applications currently employed in commercial use include, but are not limited to:(1) Silicon nitride bearing elements(2) Steel, iron, and aluminum rocker and control arms(3) Aircraft and industrial gas turbine engine components (blades, vanes, disks)(4) Cast cylinder heads and cylinder blocks(5) Sintered powder metal gears and clutch plates(6) Machined forged steel steering and transmission components (gears, shafts, racks)(7) Ceramic oxygen sensors(8) Silicon wafers(9) Gears, including those with induction hardened or carburized teeth(10) Ceramic matrix composite (CMC) material samples and components(11) Components with shot peened surfaces(12) Machined or rolled-formed fasteners(13) Components made with additive manufacturing(14) Aircraft landing gear, wheel, and brake components(15) Components made with metal injection molding5.2 General Approach and Equipment Requirements for PCRT via Swept Sine Input: 5.2.1 PCRT systems comprise hardware and software capable of inducing vibrations, recording the component response to the induced vibrations, and executing analysis of the data collected. Inputting a swept sine wave into the part has proven to be an effective means of introducing mechanical vibration and can be achieved with a high quality signal generator coupled with an appropriate active transducer in physical contact with the part. Collection of the part’s frequency response can be achieved by recording the signal generated by an appropriate passive vibration transducer. The software required to analyze the available data may include a variety of suitable statistical analysis and pattern recognition tools. Measurement accuracy and repeatability are extremely important to the application of PCRT.5.2.2 Hardware Requirements—A swept sine wave signal generator and response measurement system operating over the desired frequency range of the test part are required with accuracy better than 0.002 %. The signal generator should be calibrated to applicable industry standards. Transducers must be operable over same frequency range. Three transducers are typically used; one Drive transducer and two Receive transducers. Transducers typically operate in a dry environment, providing direct contact coupling to the part under examination. However, non-contacting response methods can operate suitably when parts are wet or oil-coated. Other than fixturing and transducer contact, no other contact with the part is allowed as these mechanical forces dampen certain vibrations. For optimal examination, parts should be placed precisely on the transducers (generally, ±0.062 in. (1.6 mm) in each axis provides acceptable results). The examination nest and cabling shall isolate the Drive from Receive signals and ground returns, so as to not produce (mechanical or electrical) cross talk between channels. Excessive external vibration or audible noise, or both, will compromise the measurements.5.3 Constraints and Limitations: 5.3.1 PCRT cannot separate parts based on visually detectable anomalies that do not affect the structural integrity of the part. It may be necessary to provide additional visual inspection of parts to identify these indications.5.3.2 Excessive process variation of parts may limit the sensitivity of PCRT. For example, mass/dimensional variations exceeding 5 % may cause PCRT to be unusable.5.3.3 Specific anomaly identification is highly unlikely. PCRT is a whole body measurement and differentiating between a crack and a void in the same location is generally not possible. It may be possible to differentiate some anomalies by using multiple patterns and training sets. The use of physics-based modeling and simulation to predict the resonance frequency spectrum of a component may also allow relationships between resonance frequencies and defect locations/characteristics to be established.5.3.4 PCRT will only work with stiff objects that provide resonances whose frequency divided by their width at half of the maximum amplitude (Q) are greater than 400 to 500. Although steel parts may be very stiff and perfectly reasonable to use for PCRT, steel foil would generally not be.5.3.5 While PCRT can be applied to painted and coated parts in many cases, the presence of some surface coatings such as vibration-absorbing materials and heavy oil layers may limit or preclude the application of PCRT.5.3.6 While PCRT can be applied to parts over a wide range of temperatures, it should not be applied to parts that are rapidly changing temperature. The part temperature should be stabilized before collecting resonance data.5.3.7 Misclassified parts in the teaching set, along with the presence of unknown anomalies in the teaching set, can significantly reduce the accuracy and sensitivity of PCRT.1.1 This practice describes a general procedure for using the process compensated resonance testing (PCRT) via swept sine input method for metallic or non-metallic parts to compare resonance patterns from a sample under test to reference teaching sets of known acceptable and targeted defect samples. The resonance pattern differences can be used to distinguish acceptable parts with normal process variation from parts with targeted material states and defects that will cause performance deficiencies. These material states and defects include, but are not limited to, cracks, voids, porosity, shrink, inclusions, discontinuities, grain and crystalline structure differences, density-related anomalies, heat treatment variations, material elastic property differences, residual stress, and dimensional variations. This practice is intended for use with instruments capable of exciting, measuring, recording, and analyzing multiple whole body, mechanical vibration resonance frequencies in acoustic or ultrasonic frequency ranges, or both.1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 This test method is one of those required to determine if the presence of a medical device may cause injury in the magnetic resonance environment. Other safety issues which should be addressed include but may not be limited to magnetically induced force (see Test Method F2052), RF heating (see Test Method F2182), and image artifact (see Test Method F2119). ISO TS 10974 addresses hazards produced by active implantable medical devices in the MR Environment.5.2 The terms MR Conditional, MR Safe, and MR Unsafe together with the corresponding icons in Practice F2503 shall be used to mark the device for safety in the MR environment.5.3 The acceptance criterion associated with this test shall be justified. If the maximum magnetically induced torque is less than the product of the longest dimension of the medical device and its weight, then the magnetically induced torque is less than the worst case torque on the device due to gravity. For this condition, it is assumed that any risk imposed by the application of the magnetically induced torque is no greater than any risk imposed by normal daily activity in the Earth's gravitational field. This is conservative. It is possible that greater torques also would not pose a hazard. (For example, device position with respect to adjacent tissue, tissue ingrowth, or other mechanisms may act to prevent device movement or forces produced by a magnetically induced torque that are greater than the torque due to gravity from causing harm to adjacent tissue.)5.4 This test method alone is not sufficient for determining if an implant is safe in the MR environment.5.5 The magnetically induced torque considered in this standard is the magneto-static torque due to the interaction of the MRI static magnetic field with the magnetization in the implant. The dynamic torque due to interaction of the static field with eddy currents induced in a rotating device is not addressed in this test method. Currents in lead wires may induce a torque as well.1.1 This test method covers the measurement of the magnetically induced torque produced by the static magnetic field in the magnetic resonance environment on medical devices and the comparison of that torque a user-specified acceptance criterion.1.2 This test method does not address other possible safety issues which may include, but are not limited to, magnetically induced deflection force, tissue heating, device malfunction, imaging artifacts, acoustic noise, interaction among devices, and the functionality of the device and the MR system.1.3 The torque considered here is the magneto-static torque due to the interaction of the MRI static magnetic field with the magnetization of the implant. The dynamic torque due to interaction of the static field with eddy currents induced in a rotating device is not addressed in this test method. Torque induced by currents in lead wires is not addressed by this standard.1.4 The methods in this standard are applicable for MR systems with a horizontal magnetic field. Not all of the methods described in this standard are applicable for use in an MR system with a vertical magnetic field. The Suspension Method and the Low Friction Surface Method require gravity to be orthogonal to the magnetically induced torsion and may not be performed using a vertical magnetic field. The Torsional Spring and Pulley Methods can be adapted to work in a vertical magnetic field, however the example apparatus are not appropriate for use in a vertical magnetic field. The Calculation Based on Measured Displacement Force Method is independent of the MR system and thus could be used for an MR system with a vertical magnetic field.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, 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.

定价： 646元 / 折扣价： 550 元 加购物车

This practice elaborates on the different types, definition of basic operational terms, conventions, referencing procedures and substances, and terms and recommended means for signal-to-noise ratio determination and data presentation in the area of high-resolution nuclear magnetic resonance (NMR) spectroscopy. Some of the basic definitions apply to wide-line NMR or to NMR of metals, but this practice is generally not intended to cover these latter areas of NMR. Also, this version does not include definitions pertaining to double resonance, nor to rotating frame experiments.1.1 This standard contains definitions of basic terms, conventions, and recommended practices for data presentation in the area of high-resolution resolution nuclear magnetic resonance (NMR) spectroscopy. Some of the basic definitions apply to wide-line NMR or to NMR of metals, but in general it is not intended to cover these latter areas of NMR in this standard. This version does not include definitions pertaining to double resonance nor to rotating frame experiments.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

定价： 0元 / 折扣价： 0 元

4.1 Young’s modulus is a fundamental mechanical property of a material.4.2 This test method is used to determine the dynamic modulus of elasticity of rectangular shapes. Since the test is nondestructive, specimens may be used for other tests as desired.4.3 This test method is useful for research and development, engineering application and design, manufacturing process control, and for developing purchasing specifications.4.4 The fundamental assumption inherent in this test method is that a Poisson’s ratio of 1/6 is typical for heterogeneous refractory materials. The actual Poisson's ratio may differ.1.1 This test method covers a procedure for measuring the resonance frequency in the flexural (transverse) mode of vibration of rectangular refractory brick or rectangularly shaped monoliths at room temperature. Young's modulus is calculated from the resonance frequency of the shape, its mass (weight), and dimensions.1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.2.1 Although the Hertz (Hz) is an SI unit, it is derived from seconds which is also an inch-pound unit.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

4.1 This test system has advantages in certain respects over the use of static loading systems in the measurement of glass and glass-ceramics:4.1.1 Only minute stresses are applied to the specimen, thus minimizing the possibility of fracture.4.1.2 The period of time during which stress is applied and removed is of the order of hundreds of microseconds, making it feasible to perform measurements at temperatures where delayed elastic and creep effects proceed on a much-shortened time scale, as in the transformation range of glass, for instance.4.2 The test is suitable for detecting whether a material meets specifications, if cognizance is given to one important fact: glass and glass-ceramic materials are sensitive to thermal history. Therefore the thermal history of a test specimen must be known before the moduli can be considered in terms of specified values. Material specifications should include a specific thermal treatment for all test specimens.1.1 This test method covers the determination of the elastic properties of glass and glass-ceramic materials. Specimens of these materials possess specific mechanical resonance frequencies which are defined by the elastic moduli, density, and geometry of the test specimen. Therefore the elastic properties of a material can be computed if the geometry, density, and mechanical resonance frequencies of a suitable test specimen of that material can be measured. Young's modulus is determined using the resonance frequency in the flexural mode of vibration. The shear modulus, or modulus of rigidity, is found using torsional resonance vibrations. Young's modulus and shear modulus are used to compute Poisson's ratio, the factor of lateral contraction.1.2 All glass and glass-ceramic materials that are elastic, homogeneous, and isotropic may be tested by this test method.2 The test method is not satisfactory for specimens that have cracks or voids that represent inhomogeneities in the material; neither is it satisfactory when these materials cannot be prepared in a suitable geometry. Non-glass and glass-ceramic materials should reference Test Method E1875  for non-material specific methodology to determine resonance frequencies and elastic properties by sonic resonance.NOTE 1: Elastic here means that an application of stress within the elastic limit of that material making up the body being stressed will cause an instantaneous and uniform deformation, which will cease upon removal of the stress, with the body returning instantly to its original size and shape without an energy loss. Glass and glass-ceramic materials conform to this definition well enough that this test is meaningful.NOTE 2: Isotropic means that the elastic properties are the same in all directions in the material. Glass is isotropic and glass-ceramics are usually so on a macroscopic scale, because of random distribution and orientation of crystallites.1.3 A cryogenic cabinet and high-temperature furnace are described for measuring the elastic moduli as a function of temperature from –195 to 1200 °C.1.4 Modification of the test for use in quality control is possible. A range of acceptable resonance frequencies is determined for a piece with a particular geometry and density. Any specimen with a frequency response falling outside this frequency range is rejected. The actual modulus of each piece need not be determined as long as the limits of the selected frequency range are known to include the resonance frequency that the piece must possess if its geometry and density are within specified tolerances.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, 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.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 This practice permits an analyst to compare the performance of an NMR spectrometer for a particular test on any given day with the instrument's prior performance for that test. The practice can also provide sufficient quantitative performance information for problem diagnosis and solving. If complete information about how a test is carried out is supplied and sufficient replicates are collected to substantiate statistical relevance, the tests in this practice can be used to establish the setting and meeting of relevant performance specifications. This practice is not necessarily meant for the comparison of different instruments with each other, even if the instruments are of the same type and model. This practice is not meant for the comparison of the performance of different instruments operated under conditions differing from those specified for a particular test.1.1 This practice covers procedures for measuring and reporting the performance of Fourier-transform nuclear magnetic resonance spectrometers (FT-NMRs) using liquid samples.1.2 This practice is not directly applicable to FT-NMR spectrometers outfitted to measure gaseous, anisotropically structured liquid, semi-solid, or solid samples; those set up to work with flowing sample streams; or those used to make hyperpolarization measurements.1.3 This practice was expressly developed for FT-NMR spectrometers operating with proton resonance frequencies between 200 MHz and 1200 MHz.1.4 This practice is not directly applicable to continuous wave (scanning) NMR spectrometers.1.5 This practice is not directly applicable to instruments using single-sideband detection.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.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： 843元 / 折扣价： 717 元 加购物车

5.1 Hydrogen content represents a fundamental quality of a petroleum distillate that has been correlated with many of the performance characteristics of that product. Combustion properties of gas turbine fuels are related primarily to hydrogen content. As hydrogen content of these fuels decreases, soot deposits, exhaust smoke, and thermal radiation increase. Soot deposits and thermal radiation can increase to the point that combustor liner burnout will occur. Hydrogen content is a procurement requirement of the following military fuels: JP-5 specified in MIL-DTL-5624, JP-8 specified in MIL-DTL-83133, and Naval Distillate Fuel specified in MIL-DTL-16884.5.2 This test method provides a simple and precise alternative to existing test methods (D3701, D4808, and D5291) for determining the hydrogen content of petroleum distillate products.1.1 This test method covers the determination of the hydrogen content of middle distillate petroleum products using a low-resolution pulsed nuclear magnetic resonance (NMR) spectrometer. The boiling range of distillates covered by the test method is 150 °C to 390 °C. While this test method may be applicable to middle distillates outside this boiling range, in such cases the precision statements may not apply. The test method is generally based on Test Methods D3701 and D4808, with a major difference being the use of a pulsed NMR spectrometer instead of a continuous wave NMR spectrometer.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 The preferred units are mass %.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： 702元 / 折扣价： 597 元 加购物车

5.1 The hydrogen content represents a fundamental quality of a petroleum product that has been correlated with many of the performance characteristics of that product.5.2 This test method provides a simple and more precise alternative to existing test methods, specifically combustion techniques (Test Methods D5291) for determining the hydrogen content on a range of petroleum products.1.1 These test methods cover the determination of the hydrogen content of petroleum products ranging from atmospheric distillates to vacuum residua using a continuous wave, low-resolution nuclear magnetic resonance spectrometer. (Test Method D3701 is the preferred method for determining the hydrogen content of aviation turbine fuels using nuclear magnetic resonance spectroscopy.)1.2 Three test methods are included here that account for the special characteristics of different petroleum products and apply to the following distillation ranges:Test Method Petroleum Products Boiling Range, °C (°F)(approximate)A Light Distillates 15–260 (60–500)B Middle Distillates 200–370 (400–700)   Gas Oils 370–510 (700–950)C Residua 510+ (950+ )1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. The preferred units are mass %.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 warning statements, see Sections 7.2 and 7.4.1.5 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