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4.1 Defacement of paint and coating films by fungal growth (mold, mildew) is a common phenomenon, and defacement by algal growth can also occur under certain conditions. It is generally known that differences in the environment, lighting, temperature, humidity, substrate pH, and other factors in addition to the coating composition affect the susceptibility of a given painted surface. This test method attempts to provide a means to comparatively evaluate different coating formulations for their relative performance under a given set of conditions. It does not imply that a coating that resists growth under these conditions will necessarily resist growth in the actual application. The method is not intended to simulate or replace indoor or outdoor exposure of paint films or related coatings.NOTE 1: It is hoped that a ranking of relative performance would be similar to that ranked from outdoor exposures. Paint designated for service in exterior conditions should be pre-conditioned by laboratory accelerated weathering prior to exposure to fungi. All pre-conditioning must be detailed in the final report. This test method however, should not be used as a replacement for exterior exposure (that is, Practice D3456) since many other factors, only a few of which are listed will affect those results.4.2 Familiarity with microbiological techniques is required. This test method should not be used by persons without at least basic microbiological training.1.1 This test method covers an accelerated method for determining the relative resistance of two or more paints or coating films to fungal growth.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 This test method is an indicator of a potential sealing problem that could occur if a sealant backing is flawed in manufacture or transportation to the job site, or abused during the installation. If flawed, some sealant backing materials, in combination with certain environmental conditions, can outgas, generating voids in the applied sealant before the sealant cures, thereby potentially compromising the cured sealant's intended performance.5.2 Voids are also known to be caused by other means and under certain conditions such as air entrapment during sealant application, trapped air in the substrate releasing into the uncured sealant, incompatibility of the sealant with the sealant backing or substrate, or inhospitable installation conditions in the field. This test method is limited to identifying the outgassing potential of a punctured sealant backing by formation of a void in the soft uncured sealant under conditions of heat and compression.1.1 This test method provides a procedure for determining the outgassing potential of a sealant backing when it is punctured during or after installation, with the puncture occurring before the sealant cures.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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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4.1 Suspended-sediment samples contain particles with a wide variety of physical characteristics. By presenting alternate approaches, these test methods allow latitude in selecting analysis methods that work best with the particular samples under study.4.2 Sediment-concentration data are used for many purposes that include: (1) computing suspended-sediment discharges of streams or sediment yields of watersheds, (2) scheduling treatments of industrial and domestic water supplies, and (3) estimating discharges of pesticides, plant nutrients, and heavy metals transported on surfaces or inside sediment particles.1.1 These test methods cover the determination of sediment concentrations in water and wastewater samples collected from lakes, reservoirs, ponds, streams, and other water bodies. In lakes and other quiescent-water bodies, concentrations of sediment in samples are nearly equal to concentrations at sampling points; in most instances, sample concentrations are not strongly influenced by collection techniques. In rivers and other flowing-water bodies, concentrations of sediment in samples depend upon the manner in which the samples are collected. Concentrations in isokinetically-collected samples can be multiplied by water discharges to obtain sediment discharges in the vicinity of the sampling points.1.2 The procedures given in these test methods are used by the Agricultural Research Service, Geological Survey, National Resources Conservation Service, Bureau of Reclamation, and other agencies responsible for studying water bodies. These test methods are adapted from a laboratory-procedure manual2 and a quality-assurance plan.31.3 These test methods include:  Sections     Test Method A—Evaporation  8 to 13  Test Method B—Filtration 14 to 19  Test Method C—Wet-Sieving-Filtration 20 to 251.4 Test Method A can be used only on sediments that settle within the allotted storage time of the samples which usually ranges from a few days to a few weeks. A correction factor must be applied if dissolved-solids concentration exceeds about 10 % of the sediment concentration.1.5 Test Method B can be used only on samples containing sand concentrations less than about 10 000 ppm and clay concentrations less than about 200 ppm. The sediment need not be settleable because filters are used to separate water from the sediment. Correction factors for dissolved solids are not required.1.6 Test Method C can be used if two concentration values are required: one for sand-size particles and one for the combination of silt and clay-size particles. The silt-clay fraction need not be settleable.1.7 These test methods must not be confused with turbidity measurements discussed in Test Method D1889. Turbidity is the optical property of a sample that causes light rays to be scattered and absorbed; it is not an accurate measure of the mass or concentration of sediment in the sample.1.8 These test methods contain some procedures similar to those in Methods of Test D1888 which pertains to measuring particulate and dissolved matter in water.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 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.1.11 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 Results from the test method suggest, within the confines of a controlled laboratory setting, the degree of aerobic aquatic biodegradation of a lubricant or components of a lubricant by measuring the evolved carbon dioxide upon exposure of the test material to an inoculum. The plateau level of CO2 evolution in this test method will suggest the degree of biodegradability of the lubricant. Test substances that achieve a high degree of biodegradation in this test may be assumed to easily biodegrade in many aerobic aquatic environments.5.2 Because of the stringency of this test, a low yield of CO2 does not necessarily mean that the test substance is not biodegradable under environmental conditions, but indicates that further testing is necessary to establish biodegradability.5.3 Information on toxicity to the inoculum of the test substance may be useful in the interpretation of low biodegradation results.5.4 Activated sewage-sludge from a sewage-treatment plant that principally treats domestic waste is considered an acceptable active aerobic inoculum available over a wide geographical area in which to test a broad range of lubricants. An inoculum derived from soil or natural surface waters, or both, or any combination of the three sources, is also appropriate for this test method.NOTE 1: Allowance for various and multiple inoculum sources provides access to a greater diversity of biochemical competency and potentially represents more accurately the capacity for biodegradation.5.5 A reference or control substance known to biodegrade is necessary in order to verify the activity of the inoculum. The test must be regarded as invalid and should be repeated using a fresh inoculum if the reference does not demonstrate a biodegradation of >60 % of the theoretical CO2 evolution within 28 days.5.6 A total CO2 evolution in the blank at the end of the test exceeding 75 mg CO2 per 3 L of medium shall be considered as invalidating the test.5.7 The water solubility or dispersibility of the lubricant or component may influence the results obtained and hence the procedure may be limited to comparing lubricants or components with similar solubilities.5.8 The ratio of carbon incorporated into cellular material to carbon released as CO2 will vary depending on the organic substrate, on the particular microorganisms carrying out the conversion, and on the environmental conditions under which the conversion takes place. In principle, this variability complicates the interpretation of the results from this test method.1.1 This test method covers the determination of the degree of aerobic aquatic biodegradation of fully formulated lubricants or their components on exposure to an inoculum under laboratory conditions.1.2 This test method is intended to specifically address the difficulties associated with testing water insoluble materials and complex mixtures such as are found in many lubricants.1.3 This test method is designed to be applicable to all lubricants that are not volatile and are not inhibitory at the test concentration to the organisms present in the inoculum.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 hazards are discussed in Section 10.1.5 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 practice provides a calculation method for determining the number of constrictions m of a non-woven geotextile (or of a layer of a composite material). This standard is not applicable to woven geotextiles, knitted geotextiles, heat-bonded geotextiles, or any other type of geosynthetic.5.2 The number of constrictions represents the number of “windows” delimited by three or more fibers, in which soil particles could migrate. This value has been found to be relevant to explain the different filtration behaviors of non-woven geotextiles with similar opening sizes but different structures for various soil conditions (see Appendix X1 for details).5.3 This value will be used in filtration research to evaluate the prediction of filtration efficiency and effectiveness of various non-woven geotextiles with similar opening sizes (Test Method D6767).5.4 Interpretation of the significance of m as calculated using this standard shall be done with care, as some non-woven structures may not reflect the hypothesis used to establish the proposed equation (see Appendix X1 for details).1.1 This practice describes the procedure used along with existing test methods to determine the number of constrictions m of mechanically bonded non-woven geotextiles, based on thickness, mass per unit area, and fiber properties1.2 The number of constrictions is a property of non-woven geotextiles, which is complementary to opening size to predict their filtration behavior. It can be used to differentiate non-woven geotextiles with similar opening sizes but different structures (thickness, weight, fiber diameter, etc.). However, more research is needed to assess its significance when comparing two products with different opening sizes.1.3 Consideration of the number of constrictions is relevant in filtration applications where piping or clogging concerns are to be controlled with a high level of confidence, that is, for filter applications in critical soils.1.4 This standard is for design purposes only and is not intended for quality control purposes.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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ASTM D7179-18 Standard Test Method for Determining Geonet Breaking Force Active 发布日期 :  1970-01-01 实施日期 : 

5.1 This method evaluates tensile breaking force of geonets for the purposes of quality control and quality assurance. Testing is performed parallel to the machine direction only, for that is the primary direction that geonets witness tensile loading. This method is an index test and is not intended for design purposes.1.1 This test method is used to measure the breaking force of a geonet.1.2 This test is applicable for manufacturing quality control (MQC) and construction quality assurance (CQA) testing, and is not recommended as a performance test.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Substrate–bonded, antimicrobial agents are not typically free to diffuse into their environment under normal conditions of use. This test method ensures good contact between the bacteria and the treated fiber, fabric, or other substrate, by constant agitation of the test specimen in a challenge suspension during the test period.5.2 The metabolic state of the challenge species can directly affect measurements of the effectiveness of particular antimicrobial agents or concentrations of agents. The susceptibility of the species to particular biocides could be altered depending on its life stage (cycle). One-hour contact time in a buffer solution allows for metabolic stasis in the population. This test method standardizes both the growth conditions of the challenge species and substrate contact times to reduce the variability associated with growth phase of the microorganism.5.3 Leaching of an antimicrobial is dependent upon the test conditions being utilized and the ultimate end use of the product. Additional testing may be required to determine if a compound is substrate-bound in all conditions or during the end use of the product.5.4 This test method cannot determine if a compound is leaching into solution or is immobilized on the substrate. This test method is only intended to determine efficacy as described in subsequent portions of the method.5.5 The test is suitable for evaluating stressed or modified specimens, when accompanied by adequate controls.NOTE 1: Stresses may include laundry, wear and abrasion, radiation and steam sterilization, UV exposure, solvent manipulation, temperature susceptibility, or similar physical or chemical manipulation.1.1 This test method is designed to evaluate the antimicrobial activity of antimicrobial-treated specimens under dynamic contact conditions. This dynamic shake flask test was developed for routine quality control and screening tests in order to overcome difficulties in using classical antimicrobial test methods to evaluate substrate-bound antimicrobials. These difficulties include ensuring contact of inoculum to treated surface (as in AATCC TM100), flexibility of retrieval at different contact times, use of inappropriately applied static conditions (as in AATCC TM147), sensitivity, and reproducibility.1.2 This test method allows for the ability to evaluate many different types of treated substrates and a wide range of microorganisms. Treated substrates used in this test method can be subjected to a wide variety of physical/chemical stresses or manipulations and allows for the versatility of testing the effect of contamination due to such things as hard water, proteins, blood, serum, various chemicals, and other contaminants.1.3 Surface antimicrobial activity is determined by comparing results from the test sample to controls run simultaneously.1.4 This test method may not be appropriate for all types of antimicrobial-treated articles or antimicrobial agents. The proper test methodology should be determined based on antimicrobial mode of action and end-use expectations (Guide E2922)1.5 Proper neutralization of all antimicrobials must be confirmed using Test Methods E1054.1.6 This test method should be performed only by those trained in microbiological techniques.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 may involve hazardous materials, operations and equipment. 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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This specification covers the minimum requirements for scales, balances, reference masses, and glass graduates used in the physical testing of hydraulic cements. Requirements for analytical reference masses and balances are not included in this specification. Reference masses for use in the methods of physical testing of hydraulic cement and related and similar materials shall conform at least to the requirements of Class 6 reference masses given in this specification. The maintenance tolerances given in this specification for Class 6 reference masses are to be considered acceptance tolerances for purposes of this specification and the maintenance tolerances twice these values. Requirements for scales, balances, and glass graduates shall conform at least to the requirements for capacity, precision and accuracy, readability, and sensitivity.1.1 This specification covers the minimum requirements for scales, balances, reference masses, and glass graduates used in the physical testing of hydraulic cements.1.2 Requirements for analytical reference masses and balances are not included in this specification, but are to be found in Test Methods C114. The use of restrictive terminology, classes, ranges, and so forth has been intentionally avoided to allow the use of this specification by other standards-writing bodies with similar requirements for reference masses and devices for determining mass, if desired.1.3 These requirements are not sufficiently descriptive to be used as the sole specifications for the purchase of reference masses or devices for determining mass without amplification.1.4 Values in SI units shall be obtained by measurement in SI units or by appropriate conversion, using the Rules for Conversion and Rounding given in IEEE/ASTM SI–10, of measurement made in other units.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 Seals are manufactured in flat extruded shapes and are primarily used to span joint openings. The seal is adhered to construction substrates utilizing a liquid applied adhesive, to seal building openings such as panel joints, metal flashing joints or other joints in place of conventional liquid applied sealants. In actual use, failure of an applied seal in an active joint is usually manifested by cohesive failure of the seal; adhesive failure between the adhesive and the substrate; adhesive failure between the adhesive and the seal; cohesive failure of the substrate or tear propagation parallel to the joint length.FIG. 1 Standard Substrate Test Specimen AssembliesFIG. 2 Beveled Bridge Joint ConfigurationFIG. 3 U-joint ConfigurationFIG. 4 Test Specimen Showing 5 mm Cut in the Middle of the Seal for Tear Propagation TestingFIG. 5 Partial TearTear propagates perpendicular to the length of the joint as shown above, left; or at any angle leading to the joint wall as shown above, right. In each case tear stops at the joint wall with an intact unbroken joint length on both sides of at least 12.5 mm.FIG. 6 TearTear propagates parallel to the joint wall and opens one side or both sides.5.2 This test method can be used for testing the adhesion of the adhesive to the substrate and to the seal, tensile load at various strains and tear resistance at various strains after the specimens are exposed to wet, cold, hot and artificial weathering conditionings. All or some of these properties are experienced on actual job sites.1.1 This test method describes a laboratory procedure for measuring modulus, tear, joint movement ability and adhesion properties of applied, Precured Elastomeric Joint Sealants, hereinafter referred to as “applied seal” and if not applied, hereinafter referred to as “seal,” on portland cement mortar as a standard substrate and or other substrates. It tests these properties after dry, wet, frozen, heat aged or artificially weather-aged conditionings, or both.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information only.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.1.4 The committee with jurisdiction over this standard is not aware of any similar standard published by another committee or organization.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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Since there is no reliable method of predicting the overall strength and deformation data of a rock mass from the results of laboratory tests on small specimens, in situ tests on large specimens are necessary, especially if the specimen size required for a given grain size would exceed the size that can be obtained for or tested in a laboratory as stated in Test Method D7012. Such tests also have the advantage that the rock specimen is tested under similar environmental conditions as prevailing for the rock mass. Since the strength of rock is dependent on the size of the test specimen and discontinuities, it is necessary to test several specimens (laboratory or field, or both) of progressively increasing size until an asymptotically constant strength value is found. This value is taken to represent the strength of the rock mass. , Note 1—Notwithstanding the statements on precision and bias contained in this test method; the precision of this test method is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice does not in itself assure reliable testing. Reliable testing depends on many factors. Practice provides a means of evaluating some of those factors. The test method is shown only being conducted underground and vertical. However, this test method could be done in a quarry or on the surface if a reaction frame could be set up to behave as a reactive surface in place of a tunnel crown.1.1 This test method covers the measurement of the deformability and strength of large in situ specimens of rock by a uniaxial compressive test. The test results take into account the effect of both intact material behavior and the behavior of discontinuities contained within the specimen block. 1.2 This test method does not cover which type of specimen should be tested or whether anisotropic factors should be considered. The specifics of the test program need to be developed prior to testing and possibly even before sampling. Such specifics would be dependent on the intended use of the data, as well as any budgetary constraints and other factors, which are outside the scope of this test method. 1.3 Theoretically there is no limit to the size of the test specimen; however, size will be controlled by the strength of the test specimen relative to the capacity of any loading apparatus and bearing capacity of the surface the apparatus must react against. Furthermore, the orientation and strength of discontinuities relative to the specimen geometry will be a factor limiting specimen size too. 1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026. 1.5 The values stated in SI units are to be regarded as the 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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5.1 The temperatures for this test are based upon the winter temperature experienced by the pavement in the geographical area for which the asphalt binder is intended.5.2 The flexural creep stiffness or flexural creep compliance, determined from this test, describes the low-temperature stress-strain-time response of asphalt binder at the test temperature within the range of linear viscoelastic response.5.3 The low-temperature thermal cracking performance of asphalt pavements is related to the creep stiffness and the m-value of the asphalt binder contained in the mix.5.4 The creep stiffness and the m-value are used as performance-based specification criteria for asphalt binders in accordance with Specification D6373.1.1 This test method covers the determination of the flexural-creep stiffness or compliance and m-value of asphalt binders by means of a bending beam rheometer. It is applicable to material having flexural-creep stiffness values in the range of 20 MPa to 1 GPa (creep compliance values in the range of 50 nPa–1 to 1 nPa–1) and can be used with unaged material or with materials aged using aging procedures such as Test Method D2872 or Practice D6521. The test apparatus may be operated within the temperature range from –36°C to 0°C.1.2 Test results are not valid for test specimens that deflect more than 4 mm or less than 0.08 mm when tested in accordance with this test method.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 Determination of the flexural modulus, beam bending strength and full assembly strength, by this test method is especially useful for product validation, design and specification purposes.5.2 Calculated values for flexural modulus, bending strength and full assembly strength will vary with specimen depth, span length, hole configurations, loading rate, and ambient test temperature. A minimum span to depth ratio of 16:1 is required for establishing the flexural modulus, wherein shear deformation effects are neglected.5.3 Validity—Stress at failure, σ, is only valid for crossarm failures due to local compression buckling. Other controlling modes of failure will dictate the ultimate phase loading capacities. For example, in-plane shear, fastener pin bearing, position hardware, center mount failures and fastener pull out will dictate the failure mode and the crossarm capacity.1.1 These test methods cover the determination of the flexural modulus and bending strength of both the tangent and deadend Fiber Reinforced Polymer (FRP) composite crossarms loaded perpendicular to the plane of minor and major axes. One method covers testing of assembled tangent crossarms including the tangent bracket and relative hardware. The other method covers testing of assembled deadend crossarms with a deadend bracket and relative phase loading hardware. The failure modes and associated stresses can be used for predicting the phase load capacities of pultruded crossarms specific to certain conductor loading scenarios exerted by conductors.1.2 The test data described in this standard can be used for predicting the vertical and horizontal component loads of deadend and tangent arms. Both deadend and tangent crossarms shall be tested in the two configurations described in Figures 1 and 2, respectively. This will permit the manufacturers to publish both vertical and horizontal design capacities for deadend crossarm configurations so that two way bending stresses, caused by catenary effects, can be considered when developing the capacity of the deadend crossarms by utility design engineers and manufacturers.1.3 The values stated in either SI units or inch-pound units 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 nonconformance with the standard.1.4 This standard will not address all factors that affect the phase loading capacity.1.5 This standard does not address the use of core materials that are added to increase the structural capacity of the crossarms. Contribution of core materials shall not be considered within the calculations provided in this standard. Use of core material properties in design computations to identify improvement in design strengths of crossarms is the sole responsibility of the designee in-charge of the project.1.6 Torsional effects occurring during standard in service usage are not considered within this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this standard.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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6.1 The assumptions of the physical system are given as follows:6.1.1 The aquifer is of uniform thickness, with impermeable upper and lower confining boundaries.6.1.2 The aquifer is of constant homogeneous porosity and matrix compressibility and constant homogeneous and isotropic hydraulic conductivity.6.1.3 The origin of the cylindrical coordinate system is taken to be on the well-bore axis at the top of the aquifer.6.1.4 The aquifer is fully screened.6.1.5 The well is 100 % efficient, that is, the skin factor, f, and dimensionless skin factor, σ, are zero.6.2 The assumptions made in defining the momentum balance are as follows:6.2.1 The average water velocity in the well is approximately constant over the well-bore section.6.2.2 Frictional head losses from flow in the well are negligible.6.2.3 Flow through the well screen is uniformly distributed over the entire aquifer thickness.6.2.4 Change in momentum from the water velocity changing from radial flow through the screen to vertical flow in the well are negligible.NOTE 1: Slug and pumping tests implicitly assume a porous medium. Fractured rock and carbonate settings may not provide meaningful data and information.NOTE 2: The function of wells in any unconfined setting in a fractured terrain might make the determination of k problematic because the wells might only intersect tributary or subsidiary channels or conduits. The problems determining the k of a channel or conduit notwithstanding, the partial penetration of tributary channels may make a determination of a meaningful number difficult. If plots of k in carbonates and other fractured settings are made and compared, they may show no indication that there are conduits or channels present, except when with the lowest probability one maybe intersected by a borehole and can be verified, such problems are described by (5) Smart (1999). Additional guidance can be found in Guide D5717.NOTE 3: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers determination of transmissivity from the measurement of water-level response to a sudden change of water level in a well-aquifer system characterized as being critically damped or in the transition range from underdamped to overdamped. Underdamped response is characterized by oscillatory changes in water level; overdamped response is characterized by return of the water level to the initial static level in an approximately exponential manner. Overdamped response is covered in Guide D4043; underdamped response is covered in Practice D5785/D5785M, Guide D4043.1.2 The analytical procedure in this practice is used in conjunction with Guide D4043 and the field procedure in Test Method D4044/D4044M for collection of test data.1.3 Limitations—Slug tests are considered to provide an estimate of the transmissivity of an aquifer near the well screen. The method is applicable for systems in which the damping parameter, ζ, is within the range from 0.2 through 5.0. The assumptions of the method prescribe a fully penetrating well (a well open through the full thickness of the aquifer) in a confined, nonleaky aquifer.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 The procedures used to specify how data are collected/recorded and calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that should generally 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 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 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Reporting of results in units other than SI shall not be regarded as nonconformance with this standard.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the 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 the 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 he ASTM consensus process.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Results from this CO2 evolution test method suggest, within the confines of a controlled laboratory setting, the degree of ultimate aerobic aquatic biodegradability of a lubricant or components of a lubricant. Test materials which achieve a high degree of biodegradation in this test method may be assumed to easily biodegrade in many aerobic aquatic environments. (See also Test Method D5864.)5.2 Because of the stringency of this test method, a low yield of CO2 does not necessarily mean that the test material is not biodegradable under environmental conditions, but indicates that further testing needs to be carried out in order to establish biodegradability.5.3 Information on the toxicity of the test material to the inoculum may be useful in the interpretation of low biodegradation results.5.4 Activated sewage-sludge from a sewage treatment plant that principally treats domestic waste may be used as an aerobic inoculum. An inoculum derived from soil or natural surface waters, or any combination of the three sources, may also be used in this test method.NOTE 1: Allowance for various and multiple inoculum sources provides access to a greater diversity of biochemical competency and potentially represents more accurately the capacity for biodegradation.5.5 A reference or control material known to biodegrade under the conditions of this test method is necessary in order to verify the activity of the inoculum. The test method must be regarded as invalid and should be repeated using a fresh inoculum if the reference does not demonstrate biodegradation to the extent of >60 % of the theoretical CO2 within 28 days.5.6 The water solubility or dispersibility of the lubricant or components may influence the results obtained and hence the procedure may be limited to comparing lubricants or components with similar solubilities.5.7 The ratio of carbon incorporated into cellular material to carbon metabolized to CO2 will vary depending on the organic substrate, on the particular microorganisms carrying out the conversion, and on the environmental conditions under which the conversion takes place. In principle, this variability complicates the interpretation of the results from this test method.5.8 The behavior of complex mixtures may not always be consistent with the individual properties of the components. The biodegradability of the components may be suggestive of whether a mixture containing these components (that is, a fully formulated lubricant) is biodegradable but such information should be used judiciously.1.1 This test method covers the determination of the degree of aerobic aquatic biodegradation of fully formulated lubricants or their components on exposure to an inoculum under controlled laboratory conditions. This test method is an ultimate biodegradation test that measures carbon dioxide (CO2) evolution.1.2 This test method is intended to specifically address the difficulties associated with testing water insoluble materials and complex mixtures such as are found in many lubricants.1.3 This test method is designed to be applicable to all non-volatile lubricants or lubricant components that are not toxic and not inhibitory at the test concentration to the organisms present in the inoculum.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. Specific hazards are discussed in Section 10.1.6 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 Knowledge of flammable limits at elevated temperatures and pressures is needed for safe and economical operation of some chemical processes. This information may be needed in order to start up a reactor without passing through a flammable range, to operate the reactor safely and economically, or to store or ship the product safely.5.2 Limits of flammability data obtained in relatively clean vessels must be carefully interpreted and may not always be applicable to industrial conditions. Surface effects due to carbon deposits and other materials can significantly affect limits of flammability, especially in the fuel-rich region. Refer to Bulletin 503 and Bulletin 627.1.1 This practice covers the determination of the lower and upper concentration limits of flammability of combustible vapor-oxidant mixtures at temperatures up to 200°C and initial pressures up to as much as 1.38 MPa (200 psia). This practice is limited to mixtures which would have explosion pressures less than 13.79 MPa (2000 psia).1.2 This practice should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.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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