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5.1 In selecting a material for human contact in medical applications, it is important to ensure that the material will not stimulate the immune system to produce an allergic reaction under relevant exposure conditions. Extractable chemicals produced by skin contact or during physiological exposures may cause allergic reactions. Therefore, this practice provides for evaluations of solid or semisolid dosage forms using material extracts or direct evaluation of the test article. The rationale for this animal model is based on the fact that the guinea pig has been shown to be an appropriate animal model for predicting human contact dermatitis. Its tractable nature, its availability from reputable suppliers, the historical database of information already acquired using this species, and the correlation of such results to data on known human allergens, all contribute to its widespread use for allergenicity studies (1-5).45.2 The need for sensitization procedures other than the maximization test (Practice F720) is based on: (1) the need for a route of exposure more similar to use conditions; (2) concern over the use of adjuvant because of its recruitment of cell types to the test site which are not typically involved in immunologic reactions, and because of the discomfort this causes in the animals; (3) absence of a proper FCA-irritant control group in the traditional maximization design; and (4) the frequency of false positives often encountered with the GPMT. Both of these tests are internationally accepted (1).AbstractThis practice is intended to determine the potential for a substance, or material extract, to elicit contact dermal allergenicity. It is intended as an alternative to the Guinea Pig Maximization Test (GPMT), given the limitations on dosage form and tendency for false positives associated with the latter test. The split adjuvant method is used when topical application is considered relevant, and the dosage form is a solid, liquid, extract, paste, or gel. The method includes four induction doses applied over a period of time to the same shaved or depilated site on guinea pigs, followed by occlusive patching. Freund's Complete Adjuvant (FCA) is injected near the dose site on a specific time, (second induction dose). Following a rest period, animals are challenged at a previously unexposed site, and the reaction evaluated at regular intervals. The closed patch method is used when topical application is relevant, but the preferred dosage form does not permit injection under the skin or intradermally, and the discomfort involved with extended occlusive patching and adjuvant use is to be avoided. It involves repeated induction doses over a period of time at the same shaved/depilated site, followed each time by occlusive wrapping. After a rest period, animals are challenged at previously untreated sites, and their reactions evaluated after a period of time.1.1 This practice is intended to determine the potential for a substance, or material extract, to elicit contact dermal allergenicity.1.2 This practice is intended as an alternative to the Guinea Pig Maximization Test (GPMT), given the limitations on dosage form and tendency for false positives associated with the latter test. See Rationale and References.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.

定价： 590元 / 折扣价： 502 元 加购物车

The formability of materials is affected by springback, the difference between the final shape of a part and the shape of the die that formed it. Materials having a large amount of springback create difficulties for the die designer and make die rework much more likely and complicated. This can add months and great costs to the achievement of successful dies. While dealing with springback in traditional metals is largely overcome by experience, new metals often have so much springback that they can only be used after much trial and error. The quantification and prediction of the tendency of metals to springback is addressed by this test method.The magnitude of the springback is a convolution of the elastic modulus, the flow stress of the metal of interest, the sheet metal thickness and the amount and type of cold work introduced by the forming process. Since the cup forming process contains features of many forming operations, the amount of springback measured by the Demeri split ring test is indicative of the behavior of the metal in many stamping operations.The amount of springback that occurs in this test is very large compared to other approaches. This improves measurement accuracy and reduces experimental error in all types of formable metals.This test does not require measurement fixtures or any sophisticated profiling equipment for accurate measurement of springback. Conventional length measuring instruments are all that is needed to perform the required measurements.This test can be used to rank materials according to their tendency to springback after a forming operation (see Refs 1-3). Since springback depends on the sheet thickness, metals should be compared at the same thickness. Experience has shown that the test can also be used in conjunction with an appropriate analysis to predict quantitatively the amount of springback occurring after a forming operation (see Refs 2-9).This test provides a method to compare springback predictions by various numerical simulation codes. Test results can be used to calibrate computer simulation codes by selecting proper control parameters and appropriate material models to achieve satisfactory correlation between simulation and test results. Test data can be used to evaluate and improve current forming and simulation capabilities.The experimental setup and test procedure are simple, and test results are highly repeatable.1.1 This test method provides a means of evaluating the springback behavior of metals in a test that simulates a stretch-draw forming process. The test method can also be used to calibrate computer simulation codes by selecting appropriate control parameters to achieve satisfactory correlation between simulation and test results.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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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： 843元 / 折扣价： 717 元 加购物车

4.1 The thick-wall ring lined drive sampler has been used for over 50 years in the arid southwest regions of the U.S. where unsaturated soils are too difficult to sample using the thin-walled tube (Practice D1587). Variations of the sampler include names such as “Dames and Moore, California, Modified California barrels” with outside barrel diameters ranging from 2.5 to 3.5 in. [60-90 mm].4 In addition to the blow count, these drive samplers have the added benefit of having a ring lined specimens that can be evaluated in the laboratory. Versions of the original Dames and Moore type sampler shown in Fig. 1 are still used, but many now use the Diamond Drill Core Manufacturers Association (DCDMA)5 specification split barrel drive samplers Fig. 2. The ring lined samplers normally have provisions for a 6-in. [150 mm] waste barrel with or without rings in the top section of the barrel. Drilling in the unsaturated soils is performed almost exclusively with hollow-stem augers (Practice D6151) because it is a dry drilling method. The test can be performed in fluid rotary or other drill holes but use of fluid rotary methods are not recommended in unsaturated soils as the drill fluid may alter the sample properties. Most operators use a 140 lb [75 kg] hammer mass but other hammer masses may be used.Practice D3740 was developed for agencies engaged in the laboratory testing and/or inspection of soil and rock. As such, it is not totally applicable to agencies performing this practice. However, user of this practice should recognize that the framework of practice D3740 is appropriate for evaluating the quality of an agency performing this practice. Currently there is no known qualifying national authority that inspects agencies that perform this practice.1.1 This practice covers procedure for thick wall, split barrel drive sampling of soil to obtain representative samples of soil for classification and laboratory testing. The sampler is considered to be a thick wall sampler with sharpened cutting shoe and ball check vent. The middle barrel section is split barrel design containing ring liners. The sampler is often driven, but can also be pushed in softer deposits. Penetration resistance data may be recorded. This standard uses procedures similar to Test Method D1586 on Penetration Resistance and Split Barrel Sampling of Soils. However, in this practice, differing hammer weights, drop heights, and different size samplers are used, so the data must not be reported as conforming to Test Method D1586 and cannot be used to determine Normalized penetration resistance data for sands in accordance with Practice D6066.1.2 This practice involves use of rotary drilling equipment (Guide D5783, Practice D6151). Other drilling and sampling procedures (Guide D6286, Guide D6169) are available and may be more appropriate. Considerations for hand driving or shallow sampling without boreholes are not addressed. Subsurface explorations should be recorded in accordance with Guide D5434. Soil samples should be classified in accordance with Practice D2488.1.3 The soil samples from this test will have some degree of disturbance because the sampler is a driven thick walled sample tube. Table 2 of Guide D6169 on Soil and Rock Sampling provides guidance for selection of soil samplers for samples that may require intact samples defined by Terminology D653 for laboratory testing. The degree of disturbance must be evaluated by the user (engineer) to determine the suitability of the sample for use in laboratory tests. If samples are not suitable for laboratory testing, other soil samplers should be used (see 4.4.1).1.4 The values stated in either inch-pound units or SI units [presented in brackets] are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard.1.6 This practice offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgement. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.6.1 This practice does not purport to comprehensively address all of the methods and the issues associated with soil sampling. Users should seek qualified professionals for the decisions as to the proper equipment and methods that would be most successful for their site exploration. Other methods may be available for monitoring soil sampling and qualified professionals should have flexibility to exercise judgement as to possible alternatives not covered in this practice.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 and health practices. The user must comply with prevalent regulatory codes, such as OSHA (Occupational Health and Safety Administration) guidelines while using this practice. For good safety practice, consult applicable OSHA regulations and other safety guides on drilling.21.8 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： 590元 / 折扣价： 502 元 加购物车

This practice is used for general soil investigations where samples are required for identification and testing. Disturbed samples can be classified in accordance with Practice D2487 and can be tested for moisture content, particle size, and Atterberg limits. The sampler can be equipped with stacked ring liners, which can be used directly for other laboratory tests. The sampler can be driven with a hammer and the penetration resistance can be recorded. Numerous combinations of hammer size and drop height have been used in practice. Hammer size and drop height should be reported. Users of this practice have derived local correlations of penetration resistance and engineering properties based on local conditions and a particular hammer system and sampler, however, the penetration resistance may differ from Test Method D1586. The user should evaluate sample quality. The process of driving the sample may disturb the soil and change the engineering properties. In soft soils, use of the thin wall tube sampler (Practice D1587) will likely result in less disturbance. In harder soils, soil coring techniques may result in less disturbance; see Practice D6151, Guide D6169. This standard addresses sampling in drill holes with drilling equipment. The sampler can be hand driven or driven in test pits without drilling equipment. If these special driving methods are used the sampling process should be reported.1.1 This practice covers procedure for thick wall, split barrel drive sampling of soil to obtain representative samples of soil for classification and laboratory testing. The sampler is considered to be a thick wall sampler with sharpened cutting shoe and ball check vent. The middle barrel section is often of split barrel design, but a solid barrel can be used and both may contain ring liners. The sampler is often driven, but can also be pushed in softer deposits. Penetration resistance data may be recorded. This standard uses procedures similar to Test Method D1586 on Penetration Resistance and Split Barrel Sampling of Soils. However, in this practice, differing hammer weights, drop heights, and different size samplers are used, so the data must not be reported as conforming to Test Method D1586 and cannot be used to determine Normalized penetration resistance data for sands in accordance with Practice D6066. 1.2 This practice involves use of rotary drilling equipment (Guide D5783, Practice D6151). Other drilling and sampling procedures (Guide D6286, Guide D6169) are available and may be more appropriate. Considerations for hand driving or shallow sampling without boreholes are not addressed. Subsurface investigations should be recorded in accordance with practice Guide D5434. Soil samples should be classified in accordance with Practice D2488. 1.3 This practice may or may not provide a sample suitable for advanced laboratory tests such as shear or consolidation testing. It is up to the user to determine if the sample quality is suitable for advanced laboratory testing for engineering properties. Driven samples can be more easily disturbed than pushed samples such as the thin wall tube in accordance with Practice D1587. However, thin wall tubes cannot be used in harder soils. In cases where it has been established that the quality of the thick wall driven sample is adequate, this practice may provide shear and consolidation specimens that can be used directly in the test apparatus without prior trimming. Some types of soils may gain or lose significant shear strength or compressibility, or both, as a result of sampling. In cases like these, suitable comparison tests should be made to evaluate the effect of sample disturbance on shear strength and compressibility. 1.4 This guide does not purport to comprehensively address all of the methods and the issues associated with soil sampling. Users should seek qualified professionals for the decisions as to the proper equipment and methods that would be most successful for their site investigation. Other methods may be available for monitoring soil sampling and qualified professionals should have flexibility to exercise judgement as to possible alternatives not covered in this guide. The practice is current at the time of issue, but new alternative and innovative methods may become available prior to revisions, therefore, users should consult with manufacturers or producers prior to specifying program requirements. 1.5 This practice offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgement. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. 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. The user must comply with prevalent regulatory codes, such as OSHA (Occupational Health and Safety Administration) guidelines while using this practice. For good safety practice, consult applicable OSHA regulations and other safety guides on drilling.

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Preface This is the second edition of CSA C656, Performance standard for split-system and single-package central air conditioners and heat pumps. It supersedes the previous edition, published in 1992 under the title Performance Standard for Single P

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5.1 Internal stress in applied coatings exhibits potential to cause a breakdown of resistance to corrosion and erosion as a result of the formation of fractures from micro-cracking and macro-cracking within the applied coating. This phenomenon can also cause blistering, peeling, reduction of fatigue strength, and loss. The resulting stress can be tensile in nature, causing the deposit to contract, or compressive in nature, causing the deposit to expand.5.2 To maintain quality assurance by the bent strip method, it is necessary to monitor production processes for acceptable levels of internal deposit stress in applied coatings. Most low values are false. Initial values tend to be lower than the actual value because of the effect of stock material edge burrs and the resistance of the stock material to bending. Excessive deposit thickness causes lower-than-true value since the coating overpowers and changes the initial modulus of elasticity of the test piece, which becomes more difficult to bend as the coating continues to build upon it. This phenomenon can be corrected considerably by use of a formula that compensates for modulus of elasticity differences between the deposit and the substrate materials, but it does remain a factor. See Eq 3.NOTE 1: The highest value of the internal deposit stress as obtained on a stress-versus-plating-thickness curve is usually the truest value of the internal deposit stress.1.1 This test method for determining the internal tensile or compressive stress in applied coatings is quantitative. It is applicable to metallic layers that are applied by the processes of electroplating or chemical deposition that exhibit internal tensile or compressive stress values from 200 psi to 145 000 psi (1.38 MPa  to 1000 MPa).1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other. Conversion between unit systems may result in errors that can cause confusion and should be avoided.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

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定价： 590元 / 折扣价： 502 元 加购物车

定价： 78元 / 折扣价： 67 元 加购物车

The test method is useful for the following:Classification of Powders—The cohesion and angle of internal friction are flowability indicators of powders and can be used to classify the powders.Quality Control—For a number of industrial applications flowability factors are used to compare the material flowability at different times during production. The material produced has to be held within given limits for each application and each powder so as to ensure trouble-free operation.Material Engineering—Powder properties are influenced by particle size, particle size distribution, fat content, humidity and other parameters. By selecting the correct parameters and the correct mixtures of powders, the required mechanical properties of the product are achieved.Design of Handling Equipment—For certain storage and conveyor equipment mathematical models exist which require the mechanical properties of powders.Note 2—The quality of the result produced by this standard is dependent on the competence of personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D 3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D 3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D 3740 provides a means of evaluating some of those factors. Practice D 3740 was developed for agencies engaged in the testing or inspection (or both) of soil and rock. As such it is not totally applicable to agencies performing this standard. However, users of this standard should recognize that the framework of Practice D 3740 is appropriate for evaluating the quality of an agency performing this standard. Currently there is no known qualifying national authority that inspects agencies that perform this standard.1.1 This test method is applied to the measurement of the mechanical properties of powders as a function of normal stress.1.2 This apparatus is suitable measuring the properties of powders and other bulk solids, up to a particle size of 5000 micron.1.3 This method comprises four different test procedures for the determination of powder mechanical properties:1.3.1 Test A—Measurement of INTERNAL FRICTION as a function of normal stress.1.3.2 Test B—Measurement of WALL FRICTION as a function of normal stress.1.3.3 Test C—Measurement of BULK DENSITY as a function of normal stress and time.1.3.4 Test D—Measurement of DEGRADATION as a function of normal stress.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D 6026.1.4.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives, and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.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 and health practices and determine the applicability of regulatory limitations prior to use.

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