定价： 689元 / 折扣价： 586 元

定价： 468元 / 折扣价： 398 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

定价： 605元 / 折扣价： 515 元

5.1 The reactivity and instability of O3 precludes the storage of O3 concentration standards for any practical length of time, and precludes direct certification of O3 concentrations as SRM's. Moreover, there is no available SRM that can be readily and directly adapted to the generation of O3 standards analogous to permeation devices and standard gas cylinders for sulfur dioxide and nitrogen oxides. Dynamic generation of O3 concentrations is relatively easy with a source of ultraviolet (UV) radiation. However, accurately certifying an O3 concentration as a primary standard requires assay of the concentration by a comprehensively specified analytical procedure, which must be performed every time a standard is needed.5.2 The primary UV standard photometers, which are usually used at a fixed location under controlled conditions, are used to certify transfer standards that are then transported to the field sites where the ambient ozone monitors are being used. See Practice D5110.5.3 The advantages of this procedure are:5.3.1 All O3 monitors in a given network or region may be traced to a single primary standard.5.3.2 The primary standard is used at only one location, under controlled conditions.5.3.3 Transfer standards are more rugged and more easily portable than primary standards.5.3.4 Transfer standards may be used to intercompare various primary standards.1.1 These practices describe means for calibrating ambient, workplace or indoor ozone monitors, using transfer standards.1.2 These practices describe five types of transfer standards:Practice A—Analytical instruments,Practice B—Boric acid potassium iodide (BAKI) manual analytical procedure,Practice C—Gas phase titration with excess nitric oxide,Practice D—Gas phase titration with excess ozone, andPractice E—Ozone generator device.1.3 These practices describe procedures to establish the authority of transfer standards: qualification, certification, and periodic recertification.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. See Section 8 for specific precautionary statements.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： 843元 / 折扣价： 717 元 加购物车

5.1 Dissolved Ozone is useful in many industries for water sanitization, TOC reduction, food preservation, cleaning-in-place of food and beverage systems, and pyrogen destruction. It is often necessary to know how much ozone has entered the water, how much remains, and the degree to which it has been removed before process use.5.2 Some applications require that contact time, DO3 concentration integrated over time, be calculated, to assure disinfection.5.3 Continuous observation of trends in these measurements are needed for continuous quality monitoring and the measurement may be used for closed loop control of ozonation.5.4 In many pure water applications and especially where water quality is regulated by the FDA or similar enforcement agencies, ozone removal must be complete before the water is used. This test method is useful for detecting and determining dissolved ozone levels in water at the trace level as well as at process concentrations where sanitization and chemical reactions occur.1.1 This test method covers the on-line and in-line determination of dissolved ozone (DO3) in low conductivity water in the range from 0.001 mg/L to 5.0 mg/L DO3 and conductivity <100 μS/cm, typical of pharmaceutical and microelectronics pure waters. DO3 is detected by correlating the response of a membrane-covered electrochemical sensor to the dissolved ozone concentration.1.2 This test method provides a more convenient means for continuous measurement than the colorimetric methods typically used for grab sample measurements.1.3 This test method has the advantage of high sensitivity as well as durability in the process environment and has few interferences.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.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： 590元 / 折扣价： 502 元 加购物车

This specification covers ozone-resistant thermoplastic elastomer insulation for electrical wires and cables operating continuously at specified conductor temperatures, within the specified voltage range, and under wet or dry conditions. 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 ac and dc voltage withstand tests as well as insulation resistance tests and should comply with the required values for aging, heat distortion, electrical permittivity, increase in capacitance, stability factor, and accelerated water absorption.1.1 This specification covers an ozone-resistant insulating compound for electrical wire and cables 14 AWG and larger. This compound consists substantially of a thermoplastic elastomer.1.2 This type of insulation is suitable for continuous operation at conductor temperatures not exceeding 90 °C in dry locations and 75 °C in wet locations. Operating voltages are not to exceed 2000 V. The minimum installation temperature is −40 °C.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.4 In many instances the insulation material cannot be tested unless it has been formed around a conductor or cable. Therefore, tests are done on insulated wire or cable in this document solely to determine the relevant property of the insulation material and not to test the conductor or completed cable.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： 515元 / 折扣价： 438 元 加购物车

This specification covers an ozone-resistant thermoplastic elastomer insulation for electrical wire and cables. This type of insulation is considered to be suitable for continuous operation at the specified conductor temperatures and operating voltages in dry locations. The minimum installation temperature is specified. Tests shall be done on insulated wire or cable solely to determine the relevant property of the insulation material and not to test the conductor or completed cable. The insulation shall conform to the prescribed physical property requirements such as (1) tensile strength and elongation at rupture before and after air oven aging test, (2) heat distortion, and (3) thickness. AC voltage, insulation resistance, and DC voltage tests shall be performed in that order when any of these tests are specified for electrical requirements. The insulation shall not show any cracks when tested by cold bend test and shall show no cracking or surface checking after exposure to the prescribed ozone concentration.1.1 This specification covers an ozone-resistant insulating compound for electrical wire and cables 14 AWG and larger. This compound consists substantially of a thermoplastic elastomer.1.2 This type of insulation is considered suitable for continuous operation at conductor temperatures not exceeding 90 °C in dry locations. Operating voltages are not to exceed 2000 V. The minimum installation temperature is –40 °C.1.3 In many instances the insulation material cannot be tested unless it has been formed around a conductor or cable. Therefore, tests are done on insulated wire or cable in this specification solely to determine the relevant property of the insulation material and not to test the conductor or completed cable.1.4 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.1.5 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： 515元 / 折扣价： 438 元 加购物车

The significance of these tests is mainly in their ability to differentiate, in a comparative sense, between different degrees of ozone resistance under the limited and specified conditions of the accelerated tests. These test methods may not give results correlating exactly with outdoor exposure tests or service performance since the correlation of accelerated ozone tests with such performance is highly dependent upon the specific conditions of both the accelerated ozone and outdoor exposures. Conditions that influence the accelerated tests are ozone partial pressure, air flow, temperature, stress-relaxation, and the bloom of additives. Outdoor or service performance is influenced by such weather conditions as rainfall, ambient temperature, sun light, and the strain cycles imposed.1.1 These test methods are used to estimate the cracking resistance of vulcanized rubber exposed under dynamic strain conditions to a chamber atmosphere containing ozone at a fixed partial pressure. The effect of sun or ultraviolet light is excluded. 1.2 These test methods are not applicable to materials ordinarily classed as hard rubber, but are adaptable to molded or extruded soft rubber. 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.

定价： 0元 / 折扣价： 0 元

4.1 General purpose and many specialty rubbers will undergo ozone cracking when exposed to ozone containing atmospheres, when the test specimens or actual use products are under a certain degree of tensile strain. Certain additives such as antiozonants and waxes inhibit or prevent this cracking. Various rubbers and rubber formulations containing such additives are customarily evaluated under static or dynamic tensile strain in laboratory ozone chambers. This standard provides for an accurate assessment of the ozone content of such chambers used in Test Methods D518, D1149, D1171, D3395 and ISO Standard 1431 I/II/III. For additional information on ozone analysis, refer to Code of Federal Regulations; Title 40 Parts 1 to 51.1.1 These test methods cover the following three types of methods for the determination of ozone content in laboratory test chambers. Method A (UV absorption) is specified for reference or referee purposes and as a means of calibration for the alternative methods; Method B, instrumental device (electrochemical or chemiluminescence); and Method C, wet chemical techniques (see Appendix X1). These methods are primarily intended for use with tests for determining rubber ozone cracking resistance and thus are applicable over the ozone level range from 25 to 200 mPa.NOTE 1: Prior to 1978, ozone concentrations were expressed in ASTM D11 Standards in parts per hundred million (pphm) of air by volume. See Appendix X2 for an explanation of the change to partial pressure in millipascals (mPa).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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For a specific hazard statement, see Note 2 and 5.1.NOTE 2: Warning—Ozone is a hazardous chemical.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

5.1 The reactivity and instability of O3 preclude the storage of O3 concentration standards for any practical length of time, and precludes direct certification of O3 concentrations as Standard Reference Materials (SRMs). Moreover, there is no available SRM that can be readily and directly adapted to the generation of O3 standards analogous to permeation devices and standard gas cylinders for sulfur dioxide and nitrogen oxides. Dynamic generation of O3 concentrations is relatively easy with a source of ultraviolet (UV) radiation. However, accurately certifying an O3 concentration as a primary standard requires assay of the concentration by a comprehensively specified analytical procedure, which must be performed every time a standard is needed (10).5.2 This practice is not designed for the routine calibration of O3 monitors at remote locations (see Practices D5011).1.1 This practice covers a means for calibrating ambient, workplace, or indoor ozone monitors, and for certifying transfer standards to be used for that purpose.1.2 This practice describes means by which dynamic streams of ozone in air can be designated as primary ozone standards.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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See Section 8 for specific precautionary statements.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

4.1 The significance of these test methods lies in the ability to differentiate between the degrees of ozone resistance under the limited and specified conditions of the accelerated tests. The degree of resistance being judged by the appearance and magnitude of the formation of cracks in the surface of the subject material.4.2 In service, rubber materials deteriorate when exposed to ozone. It is imperative to have test methods in which simple, accelerated time/exposure, comparisons of the material’s ability to resist cracking caused by ozone exposure can be empirically evaluated. Such tests can be used for producer/consumer acceptance, referee purposes, research, and development.4.3 These methods are not necessarily suited for use in purchase specifications as there may be no correlation with service performance as actual service conditions (outdoor exposure) vary widely due to geographic location and, therefore, may not yield repeatable or reproducible results.1.1 These test methods are used to estimate the effect of exposure, under surface tensile strain conditions, either dynamic or static, in an atmosphere containing specified levels of ozone concentration, expressed as partial pressure (refer to Note 1), on vulcanized rubber, rubber compounds, molded or extruded soft rubber, and other specified materials, or as may be determined empirically. The effect of naturally occurring sunlight or light from artificial sources is excluded.1.2 Previously published ASTM documents Test Method D518 and Test Methods D3395 have been included in these test methods, D1149, in 2007. Please refer to Note 2.1.2.1 Test Method D518 and Test Methods D3395 have henceforth been withdrawn and superseded by Test Methods D1149. When Test Methods D1149 is cited, or otherwise referenced, a notation shall be included to this effect. Please refer to section 3.2 for the appropriate references.1.3 The specified conditions of exposure to ozone in the controlled environments are accelerated in comparison to outdoor exposure. These accelerated ozone test methods may not give results which correlate with outdoor exposure tests or service performance.1.4 All materials, instruments, or equipment used for the determination of mass, force, dimension, ozone concentration, partial pressure, temperature, velocity, and gas exchange rate shall have direct traceability to the National Institute for Standards and Technology, or other internationally recognized organization parallel in nature.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only. Many of the stated SI units are direct conversions from the U.S. Customary System to accommodate the instrumentation, practices, and procedures that existed prior to the Metric Conversion Act of 1975.1.6 This standard involves hazardous materials, specifically ozone. It may also involve hazardous 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.NOTE 1: A discussion and explanation regarding the measurement of ozone concentrations based upon parts of ozone per unit of air versus partial pressure is provided in Test Methods D4575, specifically Appendices X1 and X2. Test Methods D4575 is also recommended as a source of background information regarding standards involving materials exposed to ozone.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

4.1 Air quality standards for ozone have been promulgated by government authorities to protect the health and welfare of the public. Though ozone itself is a toxic material, it is often complex organic compounds that cause the symptoms of smog such as tearing and burning eyes. However, ozone is the predominant oxidant and is much more easily monitored than organic species. Since ozone concentrations are also correlated with other photochemical oxidant levels, it is the substance that is specified in air quality standards and regulations.1.1 This test method describes the sampling and continuous analysis of the ozone content of the atmosphere at concentrations of 20 to 2000 μg of ozone/m3 (10 ppb (v) to 1 ppm (v)).1.2 This test method is limited in application by its sensitivity to interferences as described below. This test method is not suitable for personal sampling because of instrument size and sensitivity to vibration and ambient temperature.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. Some specific precautionary statements are presented in Section 8.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Molded or extruded rubber products must withstand the effects of ozone cracking and outdoor weathering for satisfactory use. This test enables a simple comparison of performance to be made under specified test conditions in an outdoor test. No direct correlation between test performance and service performance can be claimed due to the wide range of service conditions.1.1 This test method permits the estimation of the relative ability of rubber compounds used for applications requiring resistance to outdoor weathering.1.2 This test method is not applicable to materials ordinarily classed as hard rubber, but is adaptable to molded or extruded soft rubber materials and sponge rubber for use in window weatherstripping as well as similar automotive applications.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： 618元 / 折扣价： 526 元 加购物车