定价： 1333元 / 折扣价： 1134 元

定价： 345元 / 折扣价： 294 元

定价： 345元 / 折扣价： 294 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 515元 / 折扣价： 438 元 加购物车

定价： 515元 / 折扣价： 438 元 加购物车

定价： 515元 / 折扣价： 438 元 加购物车

5.1 Both NO2 and NO play an important role in photochemical-smog-forming reactions. In sufficient concentrations NO2 is deleterious to health, agriculture, materials, and visibility.5.2 In combustion processes, significant amounts of NO may be produced by combination of atmospheric nitrogen and oxygen; at ambient temperatures, NO can be converted to NO2 by oxygen and other atmospheric oxidants. Nitrogen dioxide also may be generated from processes involving nitric acid, nitrates, the use of explosives, and welding.1.1 This test method covers the manual determination of the combined nitrogen dioxide (NO2) and nitric oxide (NO) content, total NOx; in the atmosphere in the range from 4 to 10 000 μg/m3 (0.002 to 5 ppm (v)).1.2 The maximum sampling period is 60 min at a flow rate of 0.4 L/min.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.

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

4.1 Relative density (specific gravity) is the characteristic generally used for calculation of the volume occupied by the aggregate in various mixtures containing aggregate, including portland cement concrete, bituminous concrete, and other mixtures that are proportioned or analyzed on an absolute volume basis. Relative density (specific gravity) is also used in the computation of voids in aggregate in Test Method C29/C29M. Relative density (specific gravity) saturated surface dry (SSD) is used if the aggregate is at SSD, that is, if its absorption has been satisfied. Conversely, the relative density (specific gravity) oven dry (OD) is used for computations when the aggregate is dry or assumed to be dry.4.2 Apparent density and apparent relative density (apparent specific gravity) pertain to the solid material making up the constituent particles not including the pore space within the particles which is accessible to water.4.3 Absorption values are used to calculate the change in the mass of an aggregate due to water absorbed in the pore spaces within the constituent particles, when it is deemed that the aggregate has been in contact with water long enough to satisfy the absorption potential. The laboratory standard for absorption is that obtained after submerging dry aggregate for a prescribed period of time.NOTE 1: There are other test methods that have been used and continue to be used to determine these aggregate properties: Test Methods C127 and C128. This test method may result in values for these properties that are close to or divergent from values from other test methods.NOTE 2: The quality of the results produced by this standard are dependent upon the competence of the personnel performing the procedure and the capability, calibration, and the maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method covers the determination of relative density and absorption of fine aggregates by Method A and coarse and blended aggregates by Method B.1.2 A multi-laboratory precision and bias statement for coarse and combined aggregate tests in this standard has not been developed at this time. Therefore, this standard should not be used for acceptance or rejection of coarse and combined aggregate materials for purchasing purposes.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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. Some values have only SI units because inch-pound equivalents are not used in practice.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.

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

4.1 The dynamic interaction between the athlete and the surface is significant to the performance and comfort of the athlete. Therefore, the ability of the surface to deform under load is important. Too high a vertical deformation can affect the athlete through instability of the foot. Area elastic and combination elastic floors may be further characterized by evaluating the area deflection properties of the surface. Floors with low area deflection levels prevent or remove vibrations through damping mechanisms or design components.4.2 Vertical deformation is a widely used and recognized property of sports surfaces. Governing bodies, trade associations, and a number of international standards recognize the significance of vertical deformation. A partial list of these organizations includes: FIBA, MFMA, ASTM, EN. Even FIFA utilizes a variation of this property. Area deflection is still commonly specified within North America and one governing body (FIBA) and one trade association (MFMA) currently use this property to certify systems within the required testing for their performance programs.4.3 Vertical deformation and area deflection testing are performed with a Stuttgart Artificial Athlete (SAA) which can be created by slightly modifying the BAA (Berlin Artificial Athlete) from Test Method F2569. Laboratory experiments are to be conducted at the standard 23 ± 2°C (72 ± 4°F), but tests at additional temperatures may be performed at the request of the client. When evaluating the deflective properties of sports surfaces in the field, testing is to be conducted at the ambient temperature. Deviations from the standard temperature may cause significantly different performance levels.1.1 This method covers the quantitative measurement and normalization of deflections generated within a sports surface as an indication of the stability and comfort provided by the system.1.2 Vertical deformation provides a measure for the vertical motion generated within the sports surface system directly below the point of impact which has been normalized to a standard impact force.1.3 Area deflection provides a measure of the vibrations generated during an impact and their strength at a pre-determined distance from the point of impact.1.4 This method is not applicable to natural turf, synthetic turf or playground safety surfaces.1.5 This method is applicable to indoor and outdoor surfaces including but not limited to: wood and synthetic courts, walk/jog/run tracks, tennis courts, dance surfaces, aerobics and general fitness surfaces.1.6 The methods described are applicable in both laboratory and field settings.1.7 Area deflection testing is optional, and only applicable to area-elastic, combined elastic and mixed elastic sport surfaces. These include wood surfaces, synthetic surfaces on a sprung wood subfloor, and point elastic surfaces with an internal area elastic component.1.8 The values stated in SI units are to be regarded as standard. Units provided in parenthesis are informational only.1.9 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.1.10 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

1.1 This test method describes measurement procedures for determining physical properties of polymer matrix thermoset prepreg such as resin content, fiber volume, fiber areal weight, and thickness per ply. It provides a systematic process for measuring these physical properties using a combination of mechanical and ultrasonic methods. 1.2 The procedures are applicable to quality/process control, manufacturing acceptance and incoming inspection of prepreg composite materials. 1.3 The test method consists of a procedure for obtaining reproducible configurations for measurement of ultrasonic properties and associated geometrical properties of thermoset prepreg specimens and three calculation procedures which utilize these data to determine thickness per ply, resin content and fiber areal weight, attached as Annex A1, A2, and A3 respectively. 1.4 This standard does not purport to address all of the safety problems, 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： 0元 / 折扣价： 0 元

This specification covers laboratory performance standards for pre-blended, dry, packaged, combined materials for use in wet or dry shortcrete applications. Dry packaged shortcrete materials are categorized as to type and grade. Basic materials shall meet the requirements of this specification. Additional materials shall be permitted only if adequate test data are available to insure that the ingredient has no deleterious effects on the specified properties. Cementitious materials and aggregates shall be measured by mass (or by volume). Volumetric measurement shall be calibrated by mass. Fibres are measured by mass. Admixtures are measured by mass or volume. Shortcrete ingredients shall be thoroughly blended at a central location. Mixer performance tests shall be performed to establish the mixing time suitable for uniformity of mixing. Type FA and CA shortcrete shall meet the requirements when mixed and tested in accordance with the procedure for mixing and testing. Grade GU shortcrete shall meet the general requirements for type FA or type CA shortcrete. Grade SR shortcrete shall have sulfate resistance. Grade LP shortcrete shall have a very low chloride penetrability rating. Grade FR shotcrete shall have fiber reinforcement with a minimum average residual (Grade FR Class I) and flexural strength (Grade FR Class II) when tested.1.1 This specification covers laboratory performance standards for pre-blended, dry, packaged, combined materials for use in wet or dry shotcrete applications that are delivered to a purchaser with the ingredients uniformly mixed. The use of supplemental materials, placement, curing, or protection of the shotcrete after delivery to the purchaser is not addressed by this specification.1.2 The values stated in either SI units or inch-pound units shall be regarded separately as standard. The values stated in each system are not 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.1.3 The following safety hazards caveat pertains only to the test method portion of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

4.1 The degradation of optical properties of transparent plastics is the single greatest cause for in-service removal and replacement. Some optical qualities are inherent in the geometry, manufacturing process, and materials, and remain relatively unchanged after manufacture, while others are subject to gradual change during exposure to the service environment. Factors having an influence on the crazing of transparent plastics include stress, ultraviolet (UV), moisture, and temperature. Sufficient data has been generated to make it evident that real-world conditioning must be experienced by developmental test specimens, as opposed to testing new unexposed material to determine durability, prior to in-service usage. However, the laboratory simulation of natural weathering, and especially accelerated simulation, is imprecise and correlation of results obtained for different plastics or from using different exposure apparatus must not be attempted until a valid database has been generated for such cross-correlation.1.1 This test method covers the resistance of transparent plastics exposed to environmental conditioning (accelerated weathering) under a biaxial stress state induced by a pressure cell/test fixture.1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车