定价： 481元 / 折扣价： 409 元 加购物车

定价： 605元 / 折扣价： 515 元 加购物车

定价： 689元 / 折扣价： 586 元 加购物车

定价： 481元 / 折扣价： 409 元 加购物车

定价： 605元 / 折扣价： 515 元 加购物车

定价： 605元 / 折扣价： 515 元 加购物车

定价： 605元 / 折扣价： 515 元 加购物车

定价： 481元 / 折扣价： 409 元 加购物车

4.1 Warning tracks are playing surfaces located on the margins of the playing area for the purpose of providing a warning to the player that he or she is approaching a hazard (commonly a fence) or out-of-bounds area. In order to provide for an effective warning track surface, the warning track must be constructed and maintained in such a manner so that the player can sense the change in texture from the regular playing surface and the warning track without having to look. This feature is very important in that the player is often visually focused on the ball during play and would not be looking at the ground as he/she is running toward the warning track. The warning track must also be constructed and maintained in such a manner that the warning track itself, or the surface transition, does not pose a hazard to the players.4.2 The warning track areas of sports fields should provide a uniform surface with good footing. The change in surface texture of the warning track from the surrounding playing surface must be of enough contrast such that the player can sense the change without looking. Most often, warning track surfaces are devoid of turf or other vegetation. However, turfed warning track areas may be used in instances where such purpose is to “warn” the player of an impending hazard where the primary playing surface is a skinned area. This may be the case in softball where the entire infield playing surface is a skinned area and a turfed warning track is used along the first base and third base fencelines. Undulations, rough surface, hard or soft surface, weeds, stones, debris, wets spots, etc. detract from a good, safe warning track. The safety and effectiveness of the warning track is largely affected by construction and maintenance procedures and this guide addresses those procedures.4.2.1 During construction, consideration should be given to factors such as the physical and chemical properties of materials used in the area, freedom from stones, sticks, and other debris, and surface drainage and internal drainage. Consideration should also be given to the surface elevation such that a drastic change is not produced by the transition from the playing surface to the warning track area which may create a tripping or falling hazard.4.2.2 Maintenance practices that influence the playability of the surface include edging, dragging, rolling, watering, vegetation control, and removal of stones and debris that may adversely affect play and safety.4.3 Those responsible for the design, construction, or maintenance, or a combination thereof, of baseball and softball fields, or play areas where the need for a warning track area has been identified, will benefit from this guide.1.1 This guide covers techniques that are appropriate for the construction and maintenance of warning track areas on sports fields. This guide provides guidance for the selection of materials, such as soil and sand for use in constructing or reconditioning warning track areas and for selection of management practices that will maintain a safe and functioning warning track. Although this guide has applications to all sports where a warning track surface may be required or desired, it has specific applications to baseball/softball.1.2 This guide does not address synthetic warning tracks such as rubberized surfaces, artificial turf, or paved surfaces.1.3 Decisions in selecting construction and maintenance techniques are influenced by local soil types, climatic factors, level of play, budget, and training/ability of management personnel.1.4 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.1.5 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.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

1.1 This specification covers requirements for wakeboard threaded insert spacing, thread specifications, threaded insert diameter and thread engagement for non-track wakeboard binding systems.1.2 Units—The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that 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： 0元 / 折扣价： 0 元

4.1 The SSTR method provides for the measurement of absolute-fission density per unit mass. Absolute-neutron fluence can then be inferred from these SSTR-based absolute fission rate observations if an appropriate neutron spectrum average fission cross section is known. This method is highly discriminatory against other components of the in-core radiation field. Gamma rays, beta rays, and other lightly ionizing particles do not produce observable tracks in appropriate LWR SSTR candidate materials. However, photofission can contribute to the observed fission track density and should therefore be accounted for when nonnegligible. For a more detailed discussion of photofission effects, see 14.4.4.2 In this test method, SSTRs are placed in surface contact with fissionable deposits and record neutron-induced fission fragments. By variation of the surface mass density (μg/cm 2) of the fissionable deposit as well as employing the allowable range of track densities (from roughly 1 event/cm2 up to 105 events/cm2 for manual scanning), a range of total fluence sensitivity covering at least 16 orders of magnitude is possible, from roughly 102 n/cm 2 up to 5 × 10 18 n/cm2. The allowable range of fission track densities is broader than the track density range for high accuracy manual scanning work with optical microscopy cited in 1.2. In particular, automated and semi-automated methods exist that broaden the customary track density range available with manual optical microscopy. In this broader track density region, effects of reduced counting statistics at very low track densities and track pile-up corrections at very high track densities can present inherent limitations for work of high accuracy. Automated scanning techniques are described in Section 11.4.3 For dosimetry applications, different energy regions of the neutron spectrum can be selectively emphasized by changing the nuclide used for the fission deposit.4.4 It is possible to use SSTRs directly for neutron dosimetry as described in 4.1 or to obtain a composite neutron detection efficiency by exposure in a benchmark neutron field. The fluence and spectrum-averaged cross section in this benchmark field must be known. Furthermore, application in other neutron fields may require adjustments due to spectral deviation from the benchmark field spectrum used for calibration. In any event, it must be stressed that the SSTR-fission density measurements can be carried out completely independent of any cross-section standards (6). Therefore, for certain applications, the independent nature of this test method should not be compromised. On the other hand, many practical applications exist wherein this factor is of no consequence so that benchmark field calibration would be entirely appropriate.1.1 This test method describes the use of solid-state track recorders (SSTRs) for neutron dosimetry in light-water reactor (LWR) applications. These applications extend from low neutron fluence to high neutron fluence, including high power pressure vessel surveillance and test reactor irradiations as well as low power benchmark field measurement. (1)2 Special attention is given to the use of state-of-the-art manual and automated track counting methods to attain high absolute accuracies. In-situ dosimetry in actual high fluence-high temperature LWR applications is emphasized.1.2 This test method includes SSTR analysis by both manual and automated methods. To attain a desired accuracy, the track scanning method selected places limits on the allowable track density. Typically, good results are obtained in the range of 5 to 800 000 tracks/cm2 and accurate results at higher track densities have been demonstrated for some cases. (2) Track density and other factors place limits on the applicability of the SSTR method at high fluences. Special care must be exerted when measuring neutron fluences (E>1MeV) above 1016 n/cm2 (3) .1.3 Low fluence and high fluence limitations exist. These limitations are discussed in detail in Sections 13 and 14 and in Refs (3-5).1.4 SSTR observations provide time-integrated reaction rates. Therefore, SSTRs are truly passive-fluence detectors. They provide permanent records of dosimetry experiments without the need for time-dependent corrections, such as decay factors that arise with radiometric monitors.1.5 Since SSTRs provide a spatial record of the time-integrated reaction rate at a microscopic level, they can be used for “fine-structure” measurements. For example, spatial distributions of isotopic fission rates can be obtained at very high resolution with SSTRs.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 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： 646元 / 折扣价： 550 元 加购物车

定价： 1274元 / 折扣价： 1083 元

定价： 1229元 / 折扣价： 1045 元

5.1 Wax binders are critical for synthetic equestrian surfaces to stay together at consistencies desired. Surfaces are designed to prevent injuries and the wax binders are critical to ensure that this happens. Soxhlet extraction of wax binder is an efficient method to determine the amount of wax binder present in a synthetic equestrian surface.1.1 Equine surfaces containing wax-oil based coatings/binders must be treated and cleaned prior to the subsequent material tests described for sand and fiber surfaces. Note: skip this test for surfaces that are not wax coated.1.2 The procedures described for wax separation employ Soxhlet extraction to remove wax content from the surface and to calculate crude wax percentage in the surface. Procedures are based upon the Soxhlet extraction method, which has been modified for use on equestrian surfaces by Lab/Cor Materials, Seattle, Washington, USA.21.3 If synthetic fibers are present, then fiber solubility will need to be considered prior to Soxhlet extraction to ensure that the Soxhlet procedure will not damage fiber integrity.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

This specification covers track-resistant black thermoplastic high-density polyethylene insulation for conducting wires and cables operating continuously at a specified conductor temperature. The insulation is suitable for use for power transmission in overhead spaced-line service that is exposed to sunlight and other atmospheric environments. The prescribed tests cannot be performed unless the insulation is formed around a conductor, but these are done solely to determine the insulation properties and not to test the conductor or completed cable. Each test sample should be subjected to an ac or dc voltage withstand test at voltages that are based on the nominal thickness of the insulation and should comply with the required values for aging, heat distortion, cold blend, U-bend discharge, track resistance, tensile strength, elongation at rupture, environmental cracking, and surface resistivity.1.1 This specification covers track-resistant thermoplastic high-density polyethylene insulation. Before application to the conductor, the insulation shall comply with the requirements of Specification D1248, Type III, Class C or D, Category 5, Grade E10, J4, or J5. The requirements of Specification D1248 shall not apply to the insulation removed from the conductor.1.2 This type of insulation is considered suitable for use on wire or cable that will be used for continuous operation at conductor temperatures up to 75 °C.1.3 This insulation is suitable for use on wire or in cable used for power transmission in overhead spaced-line service, installed at temperatures above −25 °C and exposed to sunlight and other atmospheric environments between −55 and +75 °C.1.4 In many instances, the insulation cannot be tested unless it has been formed around a conductor. Therefore, tests done on insulated wire in this standard are solely to determine the relevant property of the insulation and not to test the conductor or completed cable.1.5 Whenever two sets of values are presented, in different units, the values in the first set are to be regarded as standard. The values given in parentheses are mathematical conversions that are provided for information only and are not considered standard.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车