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5.1 This test method enables the measurement of the volume of the apparent density cup to ensure that it complies with the specified volume of 25.00 cm3 ± 0.03 cm3 (cylindrical cup), or 16.39 cm3 ± 0.05 cm3 (square cup). Use of an out-of-specification cup will give erroneous apparent density values using the formulae in Test Methods B212, B329, and B417.1.1 This test method covers a procedure for measuring the volume of the apparent density cups used in Test Methods B212, B329, and B417.1.2 The apparent density cup, particularly its rim, may become worn during use, and it is recommended that the volume of the cup be checked periodically (at least every 6 months) in order to ensure that it complies with the specified volume.1.3 Units—With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm3) and gram (g) units is the long standing industry practice, the values 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.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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This guide defines purity standards for carbon dioxide to ensure the suitability of liquefied carbon dioxide gas for use in supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC) applications. This guide defines quantitation, labeling, and statistical standards for impurities in carbon dioxide that are necessary for successful SFE or SFC laboratory work, and it suggests methods of analysis for quantifying these impurities. These contaminants are those components that either cause detector signals that interfere with those of the target analytes or physically impede the SFE or SFC experiment. Also, this guide is provided for use by specialty gas suppliers who manufacture carbon dioxide specifically for SFE or SFC applications. SFE or SFC CO2 products offered with a claim of adherence to this guide will meet certain absolute purity and contaminant detectability requirements matched to the needs of current SFE or SFC techniques.1.1 This guide defines purity standards for carbon dioxide to ensure the suitability of liquefied carbon dioxide gas for use in SFE and SFC applications (see Guide E1449 for definitions of terms). This guide defines quantitation, labeling, and statistical standards for impurities in carbon dioxide that are necessary for successful SFE or SFC laboratory work, and it suggests methods of analysis for quantifying these impurities.1.2 This guide is provided for use by specialty gas suppliers who manufacture carbon dioxide specifically for SFE or SFC applications. SFE or SFC carbon dioxide (CO2) products offered with a claim of adherence to this guide will meet certain absolute purity and contaminant detectability requirements matched to the needs of current SFE or SFC techniques. The use of this guide allows different SFE or SFC CO2 product offerings to be compared on an equal purity basis.1.3 This guide considers contaminants to be those components that either cause detector signals that interfere with those of the target analytes or physically impede the SFE or SFC experiment.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 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 Typically, FT is used to identify flaws that occur in the manufacture of composite structures, or to identify and track flaws that develop during the service lifetime of the structure. Flaws detected with FT include delamination, disbonds, voids, inclusions, foreign object debris, porosity, or the presence of fluid that is in contact with the backside of the inspection surface. For example, the effect of variable ply number (or thickness), bridging, and an insert simulating delamination on heat flow into a composite is shown in Fig. 1 (left). Bridging (Fig. 1, right) or delaminated areas show up as hot spots due to discontinuous heat flow, causing heating to be localized close to the inspection surface. With dedicated signal processing and the use of representative test samples, characterization of flaw depth and size, or measurement of component thickness and thermal diffusivity, may be performed.FIG. 1 Variation of Heat Flow Into a Composite With Variable Ply Thickness (Scenarios 1, 3, and 4), Bridging (Scenario 2) And an Insert (Scenario 5) (Left), And a Post Layup Line Scan Showing Bright Spots Attributed to Bridging (Right) (Courtesy of NASA Langley Research Center)5.2 Since FT is based on the diffusion of thermal energy from the inspection surface of the specimen to the opposing surface (or the depth plane of interest), the practice requires that data acquisition allows sufficient time for this process to occur, and that at the completion of the acquisition process, the radiated surface temperature signal collected by the IR camera is strong enough to be distinguished from spurious IR contributions from background sources or system noise.5.3 This method is based on accurate detection of changes in the emitted IR energy emanating from the inspection surface during the cooling process. As the emissivity of the inspection surface falls below that of an ideal blackbody (blackbody emissivity = 1), the signal detected by the IR camera may include components that are reflected from the inspection surface. Most composite materials can be examined without special surface preparation. However, it may be necessary to coat low-emissivity, optically translucent inspection surfaces with an optically opaque, high-emissivity water-washable paint.5.4 This practice applies to the detection of flaws with aspect ratio greater than one.5.5 This practice is based on the thermal response of a specimen to a light pulse that is uniformly distributed over the plane of the inspection surface. To ensure that 1-dimensional heat flow from the surface into the sample is the primary cooling mechanism during the data acquisition period, the height and width dimensions of the heated area should be significantly greater than the thickness of the specimen, or the depth plane of interest. To minimize edge effects, the height and width dimensions of the heated area should be at least 5 % greater than the height and width dimensions of the inspection area.5.6 This practice applies to flat panels, or to curved panels where the angle between the line normal to the inspection surface and the IR camera optical axis is less than 30°. Analysis of regions with higher curvature can result in streaking artifacts due to nonuniform heating (Fig. 2).FIG. 2 Thermal Scan of a Complex Composite Shape (Left) Showing Less Effective Heating of a High Curvature Saddle-Region, Resulting in a Darker Diagonal Streak in the Thermographic Image (Right) (Courtesy of NASA Langley Research Center)1.1 This practice describes a procedure for detecting subsurface flaws in composite panels and repair patches using Flash Thermography (FT), in which an infrared (IR) camera is used to detect anomalous cooling behavior of a sample surface after it has been heated with a spatially uniform light pulse from a flash lamp array.1.2 This practice describes established FT test methods that are currently used by industry, and have demonstrated utility in quality assurance of composite structures during post-manufacturing and in-service examinations.1.3 This practice has utility for testing of polymer composite panels and repair patches containing, but not limited to, bismaleimide, epoxy, phenolic, poly(amide imide), polybenzimidazole, polyester (thermosetting and thermoplastic), poly(ether ether ketone), poly(ether imide), polyimide (thermosetting and thermoplastic), poly(phenylene sulfide), or polysulfone matrices; and alumina, aramid, boron, carbon, glass, quartz, or silicon carbide fibers. Typical as-fabricated geometries include uniaxial, cross ply, and angle ply laminates; as well as honeycomb core sandwich core materials.1.4 This practice has utility for testing of ceramic matrix composite panels containing, but not limited to, silicon carbide, silicon nitride, and carbon matrix and fibers.1.5 This practice applies to polymer or ceramic matrix composite structures with inspection surfaces that are sufficiently optically opaque to absorb incident light, and that have sufficient emissivity to allow monitoring of the surface temperature with an IR camera. Excessively thick samples, or samples with low thermal diffusivities, require long acquisition periods and yield weak signals approaching background and noise levels, and may be impractical for this technique.1.6 This practice applies to detection of flaws in a composite panel or repair patch, or at the bonded interface between the panel and a supporting sandwich core or solid substrate. It does not apply to discontinuities in the sandwich core, or at the interface between the sandwich core and a second panel on the far side of the core (with respect to the inspection apparatus).1.7 This practice does not specify accept-reject criteria and is not intended to be used as a basis for approving composite structures for service.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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5.1 LCC analysis is an economic method to evaluate alternatives that are characterized by differing cash flows over the designated project design life. The method entails calculating the LCC of each alternative capable of satisfying the functional requirements of the project and comparing them to determine which have the lowest estimated LCC over the project design life.5.2 The LCC method is particularly suitable for determining whether the higher initial cost of an alternative is economically justified by reductions in future costs (for example, operating maintenance, rehabilitation, or replacement) when compared to an alternative with lower initial costs but higher future costs. If a design alternative has both a lower initial cost and lower future costs than other alternatives, an LCC analysis is not necessary to show the former is the economically preferable choice.1.1 This practice establishes a procedure for using life cycle cost (LCC) analysis techniques to evaluate alternative drainage system designs, using plastic pipe that satisfy the same functional requirements.1.2 The LCC technique measures the present value of all relevant costs to install, operate, and maintain alternative drainage systems such as engineering, construction, maintenance, rehabilitation, or replacement over a specified period of time. The practice also accommodates any remaining residual or salvage value.1.3 The decision maker, using the results of the LCC analysis, can then identify the alternative(s) with the lowest estimated total cost based on the present value of all costs.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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ASTM F604-94 Specification for Silicone Elastomers Used in Medical Applications (Withdrawn 2001) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

1.1 This specification covers silicone elastomers intended for use as materials of construction for fabrication of medical devices. 1.2 Variations in ingredients, processing, and vulcanization (crosslinking/cure) systems of silicone elastomer are necessary to achieve the properties required in specific medical device applications. 1.2.1 An alphabetical/numerical code abbreviation is defined in this specification as what may be used to specify ingredients, crosslinking systems, processing conditions, and physical properties of many silicone elastomers used in medical device applications by a standard, abbreviated designation. 1.3 In all cases where the provisions of this specification are in conflict with those of the detailed specifications for a particular product, the latter shall take precedence. 1.3.1 When silicone elastomers are used in medical device applications where the materials requirements cannot be completely achieved by the technology prescribed in this specification, it may be necessary to adjust ingredients, processing, or cure systems to a greater extent to obtain the properties needed in these specific medical device applications. 1.3.1.1 When silicone elastomers are adjusted more extensively than prescribed in this specification, such adjustments shall be completely described and controlled in specifications for each specific material. 1.3.1.2 All sections of this specification that contain requirements pertinent to safety and effectiveness apply to all silicone elastomers used as materials of construction for medical devices, including those adjusted more broadly than defined in this specification. 1.4 While silicone elastomers have demonstrated excellent biocompatibility in medical device applications, the biocompatibility of silicone elastomers as a generic class has not been established. Many compositions and formulations are possible. Manufacturing practices, facilities, controls, process validation, and other considerations that ensure batch-to-batch duplication, assurance of identity, and quality of ingredients, as well as freedom from contamination or cross-contamination may vary widely within the silicone elastomer industry. Medical device manufacturers must ensure safety and effectiveness of each specific composition or formulation from each supplier in its intended applications. Historic, clinical, and biocompatibility data are pertinent prospectively only when all compounding, formulating, and fabrication are done in accordance with the provisions of Good Manufacturing Practice Regulations, which help ensure medical materials and devices are reasonably duplicated each time they are manufactured. 1.5 This specification is intended to assist in the development of specifications for formulated silicone elastomer compounds. It is also recommended for use in materials and finished device labeling to specify the type or types of silicone elastomers contained. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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ASTM D4127-18a Standard Terminology Used with Ion-Selective Electrodes Active 发布日期 :  1970-01-01 实施日期 : 

1.1 This terminology covers those terms recommended by the International Union of Pure and Applied Chemistry (IUPAC),2 and is intended to provide guidance in the use of ion-selective electrodes for analytical measurement of species in water, wastewater, and brines.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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Scaffolds may be composed of purely mineral or ceramic materials, or they may be composed of a composite material with its main phase being a mineral or ceramic. Scaffolds may be porous or non-porous, mechanically rigid or compliant, and degradable or non-degradable. The scaffold may or may not have undergone a surface treatment.1.1 This guidance document covers the chemical, physical, biological, and mechanical characterization requirements for biocompatible mineral- and ceramic-based scaffolds used solely as device or to manufacture tissue-engineered medical products (TEMPs). In this guide, the pure device or the TEMPs product will be referred to as scaffold.1.2 The test methods contained herein provide guidance on the characterization of the bulk physical, chemical, mechanical, and surface properties of a scaffold construct. These properties may be important for the performance of the scaffold, especially if they affect cell behavior, adhesion, proliferation and differentiation. In addition, these properties may affect the delivery of bioactive agents, the biocompatibility and the bioactivity of the final product.1.3 This document may be used as guidance in the selection of test methods for the comprehensive characterization of a raw materials, granules, pre-shaped blocks, or an original equipment manufacture (OEM) specification. This guide may also be used to characterize the scaffold component of a finished medical product.1.4 While a variety of materials can be used to manufacture such scaffolds, the composition of the final scaffold shall contain mineral or ceramic components as its main ingredients.1.5 This guide assumes that the scaffold is homogeneous in nature. Chemical or physical inhomogeneity or mechanical anisotropy of the scaffold shall be declared in the manufacturer’s material and scaffold specification.1.6 This guide addresses neither the biocompatibility of the scaffold, nor the characterization or release profiles of any biomolecules, cells, drugs, or bioactive agents that are used in combination with the scaffold.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 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 and health practices and determine the applicability of regulatory limitations prior to use.

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1.1 This specification establishes requirements for the material properties and physical properties, including dimensional tolerances, extrusion quality, and weatherability, of rigid poly (vinyl chloride) (PVC) exterior profiles used for sound walls. Methods for testing and for identifying exterior profile extrusions that comply with this specification are also provided. In addition, requirements for flexural capacity are given.NOTE 1: Information with regard to application, assembly, and installation should be obtained from the manufacturer.1.2 The material used in these exterior profiles is limited to rigid poly (vinyl chloride) (PVC) compounds in a single homogeneous extrusion or in a coextrusion of two or more PVC compounds in distinct layers.1.3 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.1.4 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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