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定价： 689元 / 折扣价： 586 元

定价： 553元 / 折扣价： 471 元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

5.1 Accurate measurement of organic carbon in water at low and very low levels is of particular interest to the electronic, life sciences, and steam power generation industries.5.2 Elevated levels of organics in raw water tend to degrade ion exchange resin capacity. Elevated levels of organics in high purity water tend to support biological growth and, in some cases, are directly detrimental to the processes that require high purity water.5.3 In power generation, naturally occurring organics can become degraded to CO2 and low molecular weight organic acids that, in turn, are corrosive to the process equipment. Their effect on conductivity may also cause water chemistry operating parameters to be exceeded, calling for plant shutdown. Halogenated and sulfonated organics may not be detectable by conductivity but at boiler temperatures will release highly corrosive chlorides, sulfates, etc.5.4 In process water in other industries, organic carbon can signify in-leakage of substances through damaged piping and components, or an unacceptable level of product loss.5.5 In wastewater treatment, organic carbon measurement of influent and process water can help optimize treatment schemes. Measurement of organic carbon at discharge may contribute to regulatory compliance.5.6 In life sciences, control of organic carbon is necessary to demonstrate compliance with regulatory limits for some types of waters.1.1 This guide covers the selection, establishment, and application of monitoring systems for carbon and carbon compounds by on-line, automatic analysis, and recording or otherwise signaling of output data. The system chosen will depend on the purpose for which it is intended (for example, regulatory compliance, process monitoring, or to alert the user to adverse trends) and on the type of water to be monitored (low purity or high purity, with or without suspended particulates, purgeable organics, or inorganic carbon). If it is to be used for regulatory compliance, the test method published or referenced in the regulations should be used in conjunction with this guide and other ASTM test methods. This guide covers carbon concentrations of 0.05 µg/L to 50 000 mg/L. Low end sensitivity and quantitative results may vary among instruments. This guide covers the on-line measurement techniques listed in Table 1. Additional laboratory test methods are available: Test Methods D4129, D4839, D5904, D6317, and D7573.1.2 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 specific hazard statements, see Section 9.1.4 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

3.1 The oxidation of silicon carbide refractories at elevated temperatures is an important consideration in the application of these refractories. The product of oxidation is amorphous silica or cristobalite, depending upon the temperature at which oxidation takes place. This oxide formation is associated with expansion and degradation of strength. The quantity of water vapor in the atmosphere greatly affects the rate of oxidation.3.2 The test, which creates and measures the expansion, is suitable for guidance in product development and relative comparison in application work where oxidation potential is of concern. The variability of the test is such that it is not recommended for use as a referee test.1.1 This test method covers the evaluation of the oxidation resistance of silicon carbide refractories at elevated temperatures in an atmosphere of steam. The steam is used to accelerate the test. Oxidation resistance is the ability of the silicon carbide (SiC) in the refractory to resist conversion to silicon dioxide (SiO2) and its attendant crystalline growth.1.2 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.1.3 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

4.1 The oxidation stability test of mineral transformer oils is a method for assessing the amount of sludge and acid products formed in a transformer oil when the oil is tested under prescribed conditions. Good oxidation stability is necessary in order to maximize the service life of the oil by minimizing the formation of sludge and acid. Oils that meet the requirements specified for this test in Specification D3487 tend to minimize electrical conduction, ensure acceptable heat transfer, and preserve system life. There is no proven correlation between performance in this test and performance in service, since the test does not model the whole insulation system (oil, paper, enamel, wire). However, the test can be used as a control test for evaluating oxidation inhibitors and to check the consistency of oxidation stability of production oils.1.1 This test method determines the resistance of mineral transformer oils to oxidation under prescribed accelerated aging conditions. Oxidation stability is measured by the propensity of oils to form sludge and acid products during oxidation. This test method is applicable to new oils, both uninhibited and inhibited, but is not well defined for used or reclaimed oils.NOTE 1: A shorter duration oxidation test for evaluation of inhibited oils is available in Test Method D2112.NOTE 2: For those interested in the measurement of volatile acidity, reference is made to IEC Method 61125. 21.2 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.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 Oxidation onset temperature is a relative measure of the degree of oxidative stability of the material evaluated at a given heating rate and oxidative environment (e.g., oxygen); the higher the OOT value the more stable the material. The OOT is described in Fig. 1. The OOT values can be used for comparative purposes and are not an absolute measurement, like the oxidation induction time (OIT) at a constant temperature (see Test Method E1858). The presence or effectiveness of antioxidants may be determined by these test methods.FIG. 1 DSC Oxidation (Extrapolated) Onset Temperature (OOT)5.2 Typical uses of these test methods include the oxidative stability of edible oils and fats (oxidative rancidity), lubricants, greases, and polyolefins.1.1 These test methods describe the determination of the oxidative properties of hydrocarbons by differential scanning calorimetry or pressure differential scanning calorimetry under linear heating rate conditions and are applicable to hydrocarbons, which oxidize exothermically in their analyzed form.1.2 Test Method A—A differential scanning calorimeter (DSC) is used at ambient pressure of one atmosphere of oxygen.1.3 Test Method B—A pressure DSC (PDSC) is used at high pressure (e.g., 3.5 MPa (500 psig) of oxygen).1.4 Test Method C—A differential scanning calorimeter (DSC) is used at ambient pressure of one atmosphere of air.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.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： 590元 / 折扣价： 502 元 加购物车

1.1 This test method covers and is intended as a rapid method for the evaluation of the oxidation stability of new mineral insulating oils containing a synthetic oxidation inhibitor. This test is considered of value in checking the oxidation stability of new mineral insulating oils containing 2,6-ditertiary-butyl para-cresol or 2,6-ditertiary-butyl phenol, or both, in order to control the continuity of this property from shipment to shipment. The applicability of this procedure for use with inhibited mineral insulating oils of more than 12 cSt at 40 °C (approximately 65 SUS at 100 °F) has not been established.1.2 The values stated in SI units are to be regarded as standard except where there is no direct equivalent for hardware designed on the inch-pound unit basis.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. (See warning in 6.7.)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 Degradation of fluid lubricants because of oxidation or thermal breakdown can result in fluid thickening or in the formation of acids or insoluble solids and render the fluid unfit for further use as a lubricant.5.2 This test method can be used for estimating the oxidation stability of oils. It can function as a formulation screening tool, specification requirement, quality control measurement, or as a means of estimating remaining service life. It shall be recognized, however, that correlation between results of this test method and the oxidation stability of an oil in field service can vary markedly with field service conditions and with various oils.5.3 This test method is designed to compliment Test Method D5846 and is intended for evaluation of fluids which do not degrade significantly within a reasonable period of time at 135 °C.1.1 This test method covers a procedure for evaluating the oxidation of inhibited lubricants in the presence of air, copper, and iron metals.1.2 This test method was developed and is used to evaluate the high temperature oxidation stability and deposit forming tendency of oils for steam and gas turbines. It has been used for testing other lubricants made with mineral oil and synthetic basestocks for compressors, hydraulic pumps, and other applications, but these have not been used in cooperative testing.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.  Identified hazardous chemicals are listed in Section 7. Before using this test method, refer to suppliers' safety labels, Material Safety Data Sheets and other technical literature.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

5.1 Insoluble material may form in oils that are subjected to oxidizing conditions.5.2 Significant formation of oil insolubles or metal corrosion products, or both, during this test may indicate that the oil will form insolubles or corrode metals, or both, resulting in varnish formation during field service. The level of varnish formation in service will be dependent on many factors (turbine design, reservoir temperature, duty-cycle, for example. peaking, cycling, or base-load duty, maintenance, and so forth) and a direct correlation between results in this test and field varnish formation are yet to be established.5.3 Oxidation condition at 120 °C under accelerated oxidation environment of Test Method D4310 and measurement of sludge and RPVOT value could reflect a practical oil quality in actual turbine operations. Results from this test should be used together with other key lubricant performance indicators (including other established oxidation and corrosion tests) to indicate suitability for service.1.1 This test method is used to evaluate the sludging tendencies of steam and gas turbine lubricants during the oxidation process in the presence of oxygen and metal catalyst (copper and iron) at an elevated temperature. This test method may be used to evaluate industrial oils (for example, circulating oils and so forth).1.2 This test method is a modification of Test Method D4310 where the sludging and corrosion tendencies of the same kinds of oils are determined after 1000 h at 95 °C in the presence of water. Water is omitted in this modification.1.3 The values stated in SI units are to be regarded as standard.1.3.1 Exception—The values in parentheses in some of the figures are provided for information only for those using old equipment based on non-SI units.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 WARNING—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Use Caution when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. The potential exists that selling mercury or mercury-containing products, or both, is prohibited by local or national law. Users must determine legality of sales in their location.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

5.1 This test method is necessary because of the need for rapid reliable tests for carbonaceous material in waters and sediments.5.2 It is used for determining the concentration of organic carbon in water that comes from a variety of natural, domestic, and industrial sources. Typically, these measurements are used to monitor organic pollutants in domestic and industrial waste water.5.3 When a sample is homogenized so that particulate, immiscible phases, and dissolved carbon from both organic and inorganic sources is determined, the measurement is called total carbon (TC). When inorganic carbon response is eliminated by removing the dissolved CO2 prior to the analysis or the dissolved CO2 concentration subtracted from the total carbon concentration, the measurement is called total organic carbon (TOC). When particulates and immiscible phases are removed prior to analysis the measurement is called dissolved carbon (DC), or dissolved organic carbon (DOC) if inorganic carbon response has been eliminated.5.4 Homogenizing or sparging of a sample, or both, may cause loss of volatile organics, thus yielding a negative error. The extent and significance of such losses must be evaluated on an individual basis. If significant quantities of volatile carbonaceous materials are present or may be present in samples organic carbon should be determined by the difference between the total carbon and the inorganic carbon concentrations. When organic carbon determined both by difference and by sparging agree it is acceptable to determine organic carbon by sparging for similar samples.5.5 The relationship of TOC to other water quality parameters such as COD and BOD is described in the literature.51.1 This test method covers the determination of total and organic carbon in water and waste water, including brackish waters and brines in the range from 2 to 20 000 mg/L. This test method has the advantages of a wide range of concentration which may be determined without sample dilution and the provision for boat or capillary introduction of samples containing sediments and particulate matter where syringe injection is inappropriate.1.2 This procedure is applicable only to that carbonaceous matter in the sample that can be introduced into the reaction zone. When syringe injection is used to introduce samples into the combustion zone, the syringe needle opening size limits the maximum size of particles that can be present in samples. Sludge and sediment samples must be homogenized prior to sampling with a micropipetor or other appropriate sampler and ladle introduction into the combustion zone is required.1.3 The precision and bias information reported in this test method was obtained in collaborative testing that included waters of the following types: distilled, deionized, potable, natural, brine, municipal and industrial waste, and water derived from oil shale retorting. Since the precision and bias information reported may not apply to waters of all matrices, it is the user’s responsibility to ensure the validity of this test method on samples of other matrices.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. For specific precautionary statements, see 9.1 and 10.2.1.1.6 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

5.1 This test method is useful for detecting and determining organic and inorganic carbon impurities in water from a variety of sources including industrial water, drinking water, and waste water.5.2 Measurement of these impurities is of vital importance to the operation of various industries such as power, pharmaceutical, semiconductor, drinking water treatment, and waste treatment. Semiconductor and power applications require measurement of very low organic carbon levels (TOC < 1 μg/L). Applications in pharmaceutical industries range from USP purified water (TOC < 500 μg/L) to cleaning applications (500 μg/L < TOC < 50 000 μg/L). Drinking waters range from <100 μg/L to 25 000 μg/L and higher. Some of these applications may include waters with substantial ionic impurities as well as organic matter.5.3 Measurement of inorganic carbon as well as total organic carbon is highly important to some applications, such as in the power industry.5.4 Continuous monitoring and observation of trends in these measurements are of interest in indicating the need for equipment adjustment or correction of water purification procedures.5.5 Refer to the Bibliography section for additional information regarding the significance of this test method.1.1 This test method covers the on-line determination of total carbon (TC), inorganic carbon (IC), and total organic carbon (TOC) in water in the range from 0.5 μg/L to 50 000 μg/L of carbon. Higher carbon levels may be determined by suitable on-line dilution. This test method utilizes ultraviolet-persulfate oxidation of organic carbon coupled with a CO2 selective membrane to recover the CO2 into deionized water. The change in conductivity of the deionized water is measured and related to carbon concentration in the oxidized sample using calibration data. Inorganic carbon is determined in a similar manner without the requirement for oxidation. In both cases, the sample is acidified to facilitate CO2 recovery through the membrane. The relationship between the conductivity measurement and carbon concentration can be described by a set of chemometric equations for the chemical equilibrium of CO2, HCO3−, H+, and OH−, and the relationship between the ionic concentrations and the conductivity. The chemometric model includes the temperature dependence of the equilibrium constants and the specific conductances resulting in linear response of the method over the stated range of TOC. See Test Method D4519 for a discussion of the measurement of CO2 by conductivity.1.2 This test method has the advantage of a very high sensitivity detector that allows very low detection levels on relatively small volumes of sample. Also, the use of two measurement channels allows determination of IC in the sample independently of organic carbon. Isolation of the conductivity detector from the sample by the CO2 selective membrane results in a very stable calibration with minimal interferences.1.3 This test method was used successfully with reagent water spiked with sodium carbonate and various organic compounds. This test method is effective with both deionized water samples and samples of high ionic strength. It is the user's responsibility to ensure the validity of this test method for waters of untested matrices.1.4 This test method is applicable only to carbonaceous matter in the sample that can be introduced into the reaction zone. The inlet system generally limits the maximum size of particles that can be introduced. Filtration may also be used to remove particles, however, this may result in removal of organic carbon if the particles contain organic carbon.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 The procedure described is for the quality control for manufacturing liquors and specifications for the purchase of such liquors.4.2 The chromium content of the liquors determines the amount to be used to obtain the desired degree of tannage, and hence may be a matter for specification in the purchase of leather.1.1 This test method covers the determination of chromic oxide in chrome tanning liquors, either simple, with added aluminum or zirconium, or with the usual masking complexing agents.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.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

4.1 These test methods have been widely used to measure the oxidation stability of extreme pressure lubricating fluids, gear oils, and mineral oils.1.1 These test methods (A and B) cover the determination of the oxidation characteristics of extreme-pressure fluid lubricants, gear oils, or mineral oils.NOTE 1: The changes in the lubricant resulting from these test methods are not always necessarily associated with oxidation of the lubricant. Some changes may be due to thermal degradation.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.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