4.1 This test method provides a means of calculating the mean relative molecular mass of petroleum oils from another physical measurement.4.2 Mean relative molecular mass is a fundamental physical constant that can be used in conjunction with other physical properties to characterize hydrocarbon mixtures.1.1 This test method covers the estimation of the mean relative molecular mass of petroleum oils from kinematic viscosity measurements at 100 °F and 210 °F (37.78 °C and 98.89 °C).2 It is applicable to samples with mean relative molecular masses in the range from 250 to 700 and is intended for use with average petroleum fractions. It should not be applied indiscriminately to oils that represent extremes of composition or possess an exceptionally narrow mean relative molecular mass range.1.2 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 General Utility—The molecular weight (MW) and molecular weight distribution (MWD) are fundamental characteristics of a polymer sample. They are used for a wide variety of correlations for fundamental studies, processing, or product applications. For example, the observed MWD is compared to one predicted from assumed kinetics or mechanisms for a polymerization reaction. Differences between the values will allow alteration of theory or experimental design. Similarly, the strength, melt flow, and other properties of a polymer sample usually are dependent on MW and MWD. Determinations of MW and MWD are used for quality control of polymers.5.2 Limitations—Because of the need for specific calibration of the polymer type under study, and because of the specific nature of polymer/solvent/column-packing interactions, this test method is valid only for polystyrene and non-exclusion effects are to be avoided. However, many of the principles of the method have been applied in generating HPSEC methods for other polymer systems, for example, using the principles of universal calibration. (see Practice D3016).1.1 This test method covers the determination of molecular weight (MW) averages and the distribution of molecular weights for linear, soluble polystyrene by high-performance size-exclusion chromatography (HPSEC). This test method is not absolute and requires the use of commercially available narrow molecular weight distribution (MWD) polystyrene standards for calibration. This test method is applicable for samples containing molecular weight components that have elution volumes falling within the elution volume range defined by polystyrene standards (that is, molecular weights generally from 2000 to 2 000 000 g·mol−1).1.2 The HPSEC is differentiated from traditional size-exclusion chromatography SEC (also referred to as gel permeation chromatography (GPC)) in that the number of theoretical plates per metre with an HPSEC system is at least ten times greater than that for traditional SEC (see Terminology D883 and Practice D3016).2 The HPSEC systems employ low-volume liquid chromatography components and columns packed with relatively small (generally 3 to 20 μm) microporous particles. High-performance liquid chromatography instrumentation and automated data handling systems for data acquisition and processing are required.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. Specific precautionary statements are given in Section 9.NOTE 1: There is no known ISO equivalent to this standard.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 This test method provides a means of determining the palladium content in fresh catalysts containing molecular sieves.4.2 This test method is not intended to cover samples containing metals other than palladium.1.1 This test method covers the determination of palladium in molecular sieve-containing fresh catalysts with about 0.5 weight % of palladium.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 and health practices and determine the applicability of regulatory limitations prior to use.

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1.1 This practice describes techniques for determining gettering rates, sorption capacity, and gas content of nonevaporable getters in the molecular flow region.1.2 Procedures for activating getters and for determining gas evolution rates are also given.1.3 The various tests described are mostly destructive in nature. In general, the tests are semiquantitative, but they can be expected to yield comparative information on a single laboratory basis. Multilaboratory reproducibility can be established only with round-robin testing. Single laboratory precision is ±15 % for gettering rate and sorption capacity. Multilaboratory reproducibility is estimated at ±50 %. Gas content measurements may have a substantially greater error due to the uncertainty of the temperature.1.4 Adverse getter-device interactions such as contamination and poisoning can occur. Such problems are beyond the scope of this practice. The user and seller should establish criteria for controlling problems such as chemical reactions, loose particles, getter location, etc.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. Specific hazard statements are given in Section 4.

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General Utility—The molecular mass (MM) and molecular mass distribution (MMD) are fundamental characteristics of a synthetic polymer that result from the polymerization process. The MM and MMD is useful for a wide variety of correlations for fundamental studies, processing and product applications. For example, it is possible to compare the observed MMD to predictions from an assumed kinetic or mechanistic model for the polymerization reaction. Differences between the values will allow alteration of the model or experimental design. Similarly, it is possible the strength, the melt flow rate, and other properties of a polymer are dependent on the MM and MMD. Determination of the MM and MMD are used for quality control of polymers and as specification in the commerce of polymers.Limitations—If the MMD is too wide, it is possible that the assumption of the constancy of the intensity scale calibration is in serious error.1.1 This test method covers the determination of molecular mass (MM) averages and the distribution of molecular masses for linear atactic polystyrene of narrow molecular mass distribution (MMD) ranging in molecular masses from 2000 g/mol to 35 000 g/mol by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). This test method is not absolute and requires the use of biopolymers for the calibration of the mass axis. The relative calibration of the intensity axis is assumed to be constant for a narrow MMD. Generally, this is viewed as correct if the measured polydispersity is less than 1.2 for the molecular mass range given above.1.2 The values stated in SI units are to be regarded as the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.Note 1—There is no known ISO equivalent to this standard.

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This specification covers ultra-high molecular weight polyethylene (UHMWPE) powder blended with alphatocopherol (vitamin E) intended for use in surgical implants. The requirements apply to alphatocopherol-containing UHMWPE in two forms. One is virgin polymer powder blended with alpha-tocopherol prior to consolidation. The second is any form fabricated from this blended, alpha-tocopherol-containing powder from which a finished product is subsequently produced. This specification does not apply to finished or semi-finished products that are doped with vitamin E after consolidation, nor to the packaged and sterilized finished implant, nor to UHMWPE materials extensively crosslinked by gamma and electron beam sources of ionizing radiation. Required material characteristics including composition, foreign matter, morphology, and mechanical characteristics are addressed by this specification.1.1 This specification covers ultra-high molecular weight polyethylene (UHMWPE) powder blended with alpha-tocopherol (Vitamin E) intended for use in surgical implants.1.2 The requirements of this specification apply to alpha-tocopherol-containing UHMWPE in two forms. One is virgin polymer powder blended with alpha-tocopherol prior to consolidation (Section 4). The second is any form fabricated from this blended, alpha-tocopherol-containing powder from which a finished product is subsequently produced (Section 5). This specification does not apply to finished or semi-finished products that are doped with Vitamin E after consolidation.1.3 Aside from blending with alpha-tocopherol, the provisions of Specifications F648 and D4020 apply. Special requirements detailed in this specification are added to describe powders containing alpha-tocopherol that will be used in surgical implants. This specification addresses material characteristics and does not apply to the packaged and sterilized finished implant. This specification also does not apply to UHMWPE materials extensively crosslinked by gamma and electron beam sources of ionizing radiation.1.4 The following precautionary caveat pertains only to the fabricated forms portion, Section 5, of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method is useful for quality-control tests on PVC compounds having a wide range of melt viscosities. Measurements are made at shear rates close to 1 s−1.5.2 In addition to the properties mentioned in Test Method D1238, this technique is sensitive to plasticizer content, polymer molecular weight, polymer stability (both thermally and rheologically), shear instability, and general composition. The sensitivity of the material to temperature necessitates slightly tighter controls than those stated in Test Method D1238.5.3 The sensitivity of this test method makes it useful for correlating with processing conditions and as an aid in predicting changes in processing. However, as a one-point measure of flow relative to shear rate, its one drawback is that the same PVC melt flow values can be obtained for materials having different processibility; the chance of this happening is minimized, however, if the compounds are similar in composition.5.4 Correlations with a wide range of processing conditions have supported the conclusions that little or no change in composition occurs during the test. Thus, this test is able to detect and follow profound changes which occur during extrusion, injection molding, milling, or mixing. These changes are due to three types of measured instability in polymers:5.4.1 Thermal instability due to temperature effect.5.4.2 Shear instability due to breaking of polymer bonds.5.4.3 Rheological instability due to nonuniform distributions of widely different viscosity or molecular weight elements.5.4.4 Thus, implications with respect to PVC molecular structural changes can be detected and predicted.1.1 This test method is an extension of Test Method D1238 specific to the measurement of flow rates of poly(vinyl chloride) (PVC) compounds while detecting and controlling various polymer instabilities associated with the flow rate.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound 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.NOTE 1: There is no known ISO equivalent to this standard.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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4.1 Published literature shows that the yield of radiolytic reactions that occur during radiation treatment increases with radiation dose level. Measurement of the products of these reactions can be used as an internal dosimeter.4.2 Trans-vinylene unsaturations are formed during ionization treatment by abstraction of a hydrogen molecule, and to a lesser extent by the recombination of two adjacent alkyl free radicals that reside on the same chain.4.3 Previous work generated calibration curves of trans-vinylene absorption area as a function of absorbed radiation dose, yielding a linear relationship for both gamma- and electron beam-irradiated polyethylene.4.4 This data can be used to determine received dose as a function of position, assuming a calibration curve (TVI versus radiation dose level) is known for the particular material and radiation conditions used, and can be used to determine uniformity of dose level in irradiated polyethylene.1.1 This test method describes the measurement of the number of trans-vinylene groups in ultra-high molecular weight polyethylene (UHMWPE) intended for use in medical implants. The material is analyzed by infrared spectroscopy.1.2 This test method is based on Guide F2102.1.3 The applicability of the infrared method has been demonstrated in other literature reports. This particular method, using the intensity (area) of the C-H absorption centered at 1370 cm-1 to normalize for the sample’s thickness, will be validated by an Interlaboratory Study (ILS) conducted according to Practice E691.1.4 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 incidental conversion of organic material to trihalomethanes and other volatile organohalides during chlorination of water is a possible health hazard and is the object of much research. This test method can be used as a rapid, simple means for determining many volatile organohalides in raw and processed water.1.1 This test method covers the analysis of drinking water. It is also applicable to many environmental and waste waters when adequate validation is included.1.2 This test method covers the determination of halomethanes, haloethanes, and some related extractable organohalides amenable to gas chromatographic measurement. The applicable concentration range for trihalomethanes is from 1 to 200 μg/L. Detection limits depend on the compound, matrix, and on the characteristics of the gas chromatographic system.1.3 For compounds not specifically included in the precision and bias section the analyst should validate the test method by collecting precision and bias data on actual samples.1.4 Confirmation of component identities is obtained by observing retention times using gas chromatographic columns of different polarities. When concentrations are sufficiently high (>50 μg/L) confirmation with halogen specific detectors or gas chromatography/mass spectrometry (GC/MS) may be used. Confirmation of purgeable compounds at levels down to 1 μg/L can be obtained using Test Method D3871 with GC/MS detection.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. Specific precautionary statements are given in Section 8.1.7 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 The weight-average molecular weight is a fundamental structure parameter of polymers, which is related to many physical properties of the bulk material, such as its rheological behavior. In addition, knowledge of the weight-average molecular weight, together with knowledge of the number-average molecular weight from osmometry, provides a useful measure of the breadth of the molecular-weight distribution.4.2 Other important uses of information on the weight-average molecular weight are correlation with dilute-solution or melt-viscosity measurements and calibration of molecular-weight standards for use in liquid-exclusion (gel-permeation) chromatography.4.3 To the extent that the light-scattering photometer is appropriately calibrated, light scattering is an absolute method and is therefore be applied to nonionic homopolymers that have not previously been synthesized or studied.1.1 This test method describes the test procedures for determining the weight-average molecular weight Mw of polymers by light scattering. It is applicable to all nonionic homopolymers (linear or branched) that dissolve completely without reaction or degradation to form stable solutions. Copolymers and polyelectrolytes are not within its scope. The procedure also allows the determination of the second virial coefficient, A2, which is a measure of polymer-solvent interactions, and the root-mean-square radius of gyration (s2)1/2, which is a measure of the dimensions of the polymer chain.1.2 The molecular-weight range for light scattering is, to some extent, determined by the size of the dissolved polymer molecules and the refractive indices of solvent and polymer. A range frequently stated is 10,000 to 10,000,000, is often extended in either direction with suitable systems and by the use of special techniques.1.2.1 The lower limit to molecular weight results from low levels of excess solution scattering over that of the solvent. The greater the specific refractive increment dn/dc (difference in refractive indices of solution and solvent per unit concentration), the greater the level of solution scattering and the lower the molecular weight that shall be determined with a given precision.1.2.2 The upper limit to molecular weight results from the angular dependence of the solution scattering, which is determined by the molecular size. For sufficiently large molecules, measurements must be made at small scattering angles, which are ultimately outside the range of the photometer used.1.3 The values stated in SI units are to be regarded as 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.NOTE 1: There is no known ISO equivalent to this standard.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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1.1 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice summarizes two methods that may be used to precondition UHMWPE by the absorption of lipids to differentiate the simulated in vitro oxidative stability of UHMWPEs, after lipid exposure.4.1.1 Procedure A, High Squalene Absorption—This method of preconditioning with lipids may be used for comparative oxidative stability testing to screen different materials under aggressive conditions.4.1.2 Procedure B, Mixed Lipid Absorption—This method of preconditioning may be used for comparative oxidative stability testing under mild conditions that more closely simulate in-vivo conditions.4.2 This practice may be used to accelerate the oxidation of UHMWPE components when using elevated temperature and elevated oxygen pressure according to the methods of Practice F2003. Under real-time conditions such as implantation, oxidative changes to UHMWPE formulations may take months or years to produce changes that may result in deleterious mechanical performance. The method outlined in this practice permits the preparation of UHMWPE for evaluation of oxidative stability in a relatively short period of time (for example, weeks).4.3 This practice may also be used to precondition UHMWPE test specimens prior to characterization of their physical and chemical properties. In particular, this practice may be used for preconditioning with lipids prior to oxidation induction time (OIT) testing as outlined in Test Method D3895.1.1 It is the intent of this practice to permit an investigator to incorporate lipids found in the synovial environment into polymeric specimens. This can be used as a preconditioning step to evaluate the oxidative stability of ultra-high-molecular-weight polyethylene (UHMWPE) materials. This practice describes a laboratory procedure for preconditioning of UHMWPE specimens.1.2 The preconditioned UHMWPE can be aged at elevated temperature and at elevated oxygen pressure following methods of accelerated aging described in Practice F2003, to accelerate oxidation of the material and thereby allow for the evaluation of its long-term chemical stability.1.3 The preconditioned UHMWPE can be tested without further aging using a method to evaluate oxidative stability such as oxidation induction time as described in Test Method D3895.1.4 The methods of this practice may be used on any type of UHMWPE material intended for use in total joint arthroplasty in a synovial joint (for example, conventional, cross-linked, antioxidant stabilized, etc.). See Appendix X1.1.5 Although the preconditioning method followed by accelerated aging described by this practice will permit an investigator to compare the oxidative stability of different UHMWPE materials, it is recognized that this method is not known to simulate the degradative mechanisms for an implant during real-time shelf aging or in vivo. The described methods have not been evaluated for mechanical testing under cyclic loading.1.6 The preconditioning and accelerated aging methods specified herein are intended to rank the resistance to oxidation of materials as a result of the absorption of lipids, which may occur in UHMWPE following implantation, and to determine susceptibility to oxidative changes. The methods have not been evaluated for use in preconditioning of UHMWPE components for subsequent testing of mechanical or wear properties. Procedure A should not be used for preconditioning of UHMWPE components for subsequent testing of mechanical or wear properties.1.7 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are for information only and are not considered standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This guide aims to provide guidance for a range of assessments and evaluations to aid in preclinical research and device development of various UHMWPE components in orthopedic and spinal devices used for the repair of musculoskeletal disorders.4.2 This guide includes brief descriptions of various assessments, representative data, processing conditions, and intended use or uses, as well as the qualitative and quantitative analyses of the UHMWPE powder to a finished product component.4.3 The user is encouraged to use appropriate ASTM International and other standards to conduct the physical, chemical, mechanical, biocompatibility, and preclinical tests on UHMWPE materials, device components, or devices before assessment of an in vivo model.4.4 Assessments of UHMWPE should be performed in accordance with the provisions of 21 CFR 58 where feasible.4.5 Studies to support investigational device exemption (IDE), premarket approval (PMA), or 510K submissions should conform to appropriate Food and Drug Administration (FDA) guidelines for the development of medical devices.4.6 Assessments with physical, chemical, mechanical, biocompatibility, and preclinical tests on UHMWPE components are not necessarily predictive of human results and therefore should be interpreted cautiously with respect to potential applicability to human conditions. Referenced UHMWPE publications can be found in the References section at the end of this guide for further review.(A) For materials terminally sterilized by gamma or e-beam irradiation.1.1 This guide covers general guidelines for the physical, chemical, biocompatibility, mechanical, and preclinical assessments of ultra-high molecular weight polyethylene (UHMWPE) in implantable orthopedic and spinal devices intended to replace a musculoskeletal joint. The UHMWPE components may include knee, hip, shoulder, elbow, ankle, total disc replacement, toe, finger, and wrist joint implant devices. This guide does not cover UHMWPE in fiber or tape forms.1.2 This guide includes a description and rationale of assessments for the various UHMWPE types and processing conditions. Assessment testing based on physical, chemical, biocompatibility, mechanical, and preclinical analyses are briefly described and referenced. The user should refer to specific test methods for additional details.1.3 This guide does not attempt to define all of the assessment methods associated with UHMWPE components in orthopedic and spinal devices.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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This specification provides for the identification of virgin, unmodified homopolymer ultra-high-molecular-weight polyethylene (UHMW-PE) molding and extrusion plastic materials in the form of powder, granules, or pellets. This specification is not intended to differentiate between various molecular weight grades of commercially available UHMW-PE, nor does it function to provide specific engineering data for design purposes. Sampled specimens shall be tested for dilute solution viscosity.1.1 This specification provides for the identification of virgin, natural color, unmodified homopolymer ultra-high-molecular-weight polyethylene (UHMWPE) plastics molding and extrusion materials. This identification is made in such a manner that the seller and purchaser can agree on the acceptability of different commercial lots or shipments.1.2 This specification also provides guidance for the characterization of UHMWPE materials based on various mechanical, thermal, electrical, and other analyses.1.3 It is not intended to differentiate between various molecular weight grades of ultra-high-molecular-weight polyethylene commercially available.1.4 It is not the function of this specification to provide specific engineering data for design purposes.1.5 Ultra-high-molecular-weight polyethylenes, as defined in this specification, are those linear polymers of ethylene which have a relative viscosity of 1.44 or greater, in accordance with the test procedures described herein.1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.7 The following precautionary caveat pertains only to the test method portions in Section 7 and the Annex and Appendixes, of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 1: This standard and ISO 11542-1 address the same subject matter, but differ in technical content. ISO 11542-1 provides a classification system based on various characteristics and a range of viscosity numbers determined in accordance with ISO 1628-3.1.8 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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4.1 This test method provides a means of determining the palladium content in fresh catalysts containing molecular sieves.4.2 This test method is not intended to cover samples containing precious metals other than palladium.1.1 This test method covers the determination of palladium in molecular sieve-containing fresh catalysts with about 0.5 weight % of palladium.1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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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