定价： 590元 / 折扣价： 502 元 加购物车

定价： 0元 / 折扣价： 0 元 加购物车

5.1 This test method is suitable for research or for quality control to characterize TDI and MDI.5.2 This test method was developed to overcome problems with low-level acidity determinations that use glass electrodes in the presence of reagent alcohol solvents. Reagent alcohols contain acidic and basic species, which complicate the glass electrode methods at low levels of acidity.1.1 This test method measures the hydrolyzable chlorine content of monomeric, aromatic isocyanates used as polyurethane raw materials and expresses it as HCl acidity. The test method is applicable to toluene diisocyanate (TDI) and monomeric methylene di(phenylisocyanate), known as MDI. The main sources of hydrolyzable chlorine and, therefore, acidity in monomeric aromatic isocyanates are carbamyl chlorides, acid chlorides, and dissolved phosgene. All of these compounds react with alcohols and water to form hydrochloric acid.1.2 This test method applies only to monomeric isocyanates in which all of the acidity is derived from species that generate HCl on solvolysis.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.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.

定价： 515元 / 折扣价： 438 元 加购物车

This specification establishes the properties and requirements for the pigments commercially known as raw sienna and burnt sienna in the dry and paste in oil forms. The dry pigments shall be sampled and tested as appropriate, and conform accordingly to composition requirements as to iron oxide, calcium compounds, moisture and other volatile matter, coarse particles (total residue retained on a No. 325 sieve), and organic colors. The pigments in paste in oil form shall conversely be tested and conform to composition requirements as to pigment, nonvolatile vehicle, moisture by distillation, and coarse particles (total residue retained on a No. 325 sieve). Both forms shall adhere to specified mass color, tint character, and tinting strength requirements as well.1.1 This specification covers the pigments commercially known as raw sienna and burnt sienna.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.

定价： 515元 / 折扣价： 438 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车

4.1 The physico-chemical characteristics of the raw or starting material used in regenerative medicine scaffolds carries significant potential to affect product performance by influencing cell behavior and/or the release of bioactive molecules or drugs. This guide describes recommended specifications or characterizations of raw or starting materials to ensure reproducibility prior to their fabrication into implantable tissue-engineering scaffolds and/or controlled release matrices.AbstractThis guide addresses material characteristics of raw or virgin materials in a nonfabricated form that will ultimately undergo additional processing into growth, support, or delivery vehicles for cells or biomolecules. The substrate material shall have specifications for an extensive set of chemical and physical properties prescribed. Test methods shall be performed in order to determine the chemical and physical properties of the material.1.1 This document provides guidance on writing a materials specification for raw or starting materials intended for use in tissue engineering scaffolds for growth, support, or delivery of cells and/or biomolecules. This guide does not apply to materials that are already in a scaffold form or are finished tissue-engineered medical products.1.2 The purpose of this guide is to provide a compendium of relevant existing standards and test methods for materials already commonly used within medical products and to provide characterization guidance for interim use of raw materials for which a standard does not exist.1.3 This guide covers specifications and characterizations of all the major classes of materials including polymers, ceramics, metals, composites, and natural tissues of human, animal, or plant origin. This guide does not apply to pharmaceuticals.1.4 This guide is focused on specification of chemical, physical, and mechanical properties of the raw or starting material. It does not include safety and biocompatibility requirements since safety and biocompatibility testing is typically done on materials fabricated into a final form to include all possible effects of fabrication and sterilization techniques.1.5 Compliance with materials specifications developed in accordance with this standard may not necessarily result in a material suitable for its intended purpose. Additional testing specific to the intended use may be required.

定价： 590元 / 折扣价： 502 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车

5.1 General Utility: 5.1.1 It is necessary to know the hydroxyl number of polyols in order to formulate polyurethane systems.5.1.2 This practice is suitable for research, quality control, specification testing, and process control.5.2 Limitations: 5.2.1 Factors affecting the NIR spectra of the analyte polyols need to be determined before a calibration procedure is started. Chemical structure, interferences, any nonlinearities, the effect of temperature, and the interaction of the analyte with other sample components such as catalyst, water and other polyols needs to be understood in order to properly select samples that will model those effects which cannot be adequately controlled.5.2.2 Calibrations are generally considered valid only for the specific NIR instrument used to generate the calibration. Using different instruments (even when made by the same manufacturer) for calibration and analysis can seriously affect the accuracy and precision of the measured hydroxyl number. Procedures used for transferring calibrations between instruments are problematic and are to be utilized with caution following the guidelines in Section 16. These procedures generally require a completely new validation and statistical analysis of errors on the new instrument.5.2.3 The analytical results are statistically valid only for the range of hydroxyl numbers used in the calibration. Extrapolation to lower or higher hydroxyl values can increase the errors and degrade precision. Likewise, the analytical results are only valid for the same chemical composition as used for the calibration set. A significant change in composition or contaminants can also affect the results. Outlier detection, as discussed in Practices E1655, is a tool that can be used to detect the possibility of problems such as those mentioned above.1.1 This standard covers a practice for the determination of hydroxyl numbers of polyols using NIR spectroscopy.1.2 Definitions, terms, and calibration techniques are described. Procedures for selecting samples, and collecting and treating data for developing NIR calibrations are outlined. Criteria for building, evaluating, and validating the NIR calibration model are also described. Finally, the procedure for sample handling, data gathering and evaluation are described.1.3 The implementation of this standard requires that the NIR spectrometer has been installed in compliance with the manufacturer's specifications.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.NOTE 1: This standard is equivalent ISO 15063.1.6 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.

定价： 590元 / 折扣价： 502 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车

5.1 This test method can be used for research or for quality control to characterize aromatic isocyanates and prepolymers of moderate to high acidity. Acidity correlates with performance in some polyurethane systems.1.1 This test method determines the acidity, expressed as parts per million (ppm) of HCl, in aromatic isocyanate samples of greater than 100–ppm acidity. The test method is applicable to products derived from toluene diisocyanate and methylene-bis-(4–phenylisocyanate) (see Note 1).NOTE 1: This test method is equivalent to ISO 14898, Test Method A.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.

定价： 515元 / 折扣价： 438 元 加购物车

定价： 515元 / 折扣价： 438 元 加购物车

5.1 This test method is considered satisfactory for acceptance testing of commercial shipments since this test method has been used extensively in the trade for acceptance testing.5.1.1 In case of dispute arising from differences in reported test results when using Test Method D584 for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative testing to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens that are as homogenous as possible and that are from a lot of the type material in question. The test specimens should then be assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and the supplier must agree to interpret future test results in the light of known bias.5.2 The wool-base content of wool in any condition or form is a basic quantity. From it may be calculated commercial masses or yields in any of the various recognized defined systems used in international commerce (Note 1).5.2.1 The procedures for determining the wool base content of greasy wool provided in this test method and in IWTO Method 19-85(E) are in essential agreement.NOTE 3: This is not true for scoured wool, as IWTO Method 19-85(E) does not require rescouring of scoured wool containing less than 5 % residual grease.5.3 Not all of the wool base present in a lot of raw wool can be recovered in useful form by commercial cleaning operations. The amount of wool loss varies, depending on factors such as the character of the wool, the nature and percentage of the impurities present, the cleaning process and equipment used, and so forth.5.4 No ASTM standard specifies or recommends any specific procedure or practice for estimating anticipated loss of wool during commercial cleaning (or other) operations. The following statutory practice is described solely for information:5.4.1 For the purpose of duty assessment on importations of raw wool into the United States, the Tariff Schedules of the United States5 provides a statutory formula for calculating the allowance to be made for wool “that would ordinarily be lost during commercial cleaning operations.” The formula is based on the clean wool fiber present (called “absolute clean content” in the Tariff Schedules) and on the vegetable matter present. The allowance, in terms of clean wool fiber present, is equal to 0.5 % of the clean wool fiber present plus 60 % of the vegetable matter present, the total allowance not to exceed 15 % of the clean wool fiber present. The dutiable quantity (called “clean yield” in the Tariff Schedules) is the difference between the clean wool fiber present and the allowance so calculated.1.1 This test method covers a laboratory procedure for the determination of the wool base content and the clean wool fiber present in samples of raw wool. This test method is also applicable to other animal fibers such as mohair, cashmere, alpaca, and camel hair.NOTE 1: Sampling of lots of raw wool in packages is covered in Practice D1060; the determination of vegetable matter and other alkali-insoluble impurities in scoured wool is covered in Test Method D1113; the determination of wool content on a commercial scale is covered in Test Method D1334. For factors for the conversion of woolbase content to its equivalent in terms of scoured wool, top, or noil of various commercially specified compositions (formerly covered in the appendix of this test method), refer to Practice D2720.NOTE 2: Because of the trade practice the term weight is used in this test method instead of the technically correct term mass.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.

定价： 590元 / 折扣价： 502 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车

定价： 590元 / 折扣价： 502 元 加购物车