定价： 590元 / 折扣价： 502 元 加购物车

4.1 The intent of this practice is to indicate standard welded specimens and welding procedures for evaluating the SCC characteristics of weldments in corrosive environments. The practice does not recommend the specific corrosive media that may be selected by the user depending upon the intent of his investigation. Specific corrosive media are included in Practices G35, G36, G37, and G44. Other environments can be used as required.1.1 This practice covers procedures for the making and utilization of test specimens for the evaluation of weldments in stress-corrosion cracking (SCC) environments.1.2 Test specimens are described in which (a) stresses are developed by the welding process only, (b) stresses are developed by an externally applied load in addition to the stresses due to welding, and (c) stresses are developed by an externally applied load only with residual welding stresses removed by annealing.1.3 This practice is concerned only with the welded test specimen and not with the environmental aspects of stress-corrosion testing. Specific practices for the bending and loading of test specimens, as well as the stress considerations involved in preparation of C-rings, U-bend, bent-beam, and tension specimens are discussed in other ASTM standards.1.4 The actual stress in test specimens removed from weldments is not precisely known because it depends upon the level of residual stress from the welding operation combined with the applied stress. A method for determining the magnitude and direction of residual stress which may be applicable to weldment is described in Test Method E837. The reproducibility of test results is highly dependent on the preparation of the weldment, the type of test specimen tested, and the evaluation criteria used. Sufficient replication should be employed to determine the level of inherent variability in the specific test results that is consistent with the objectives of the test program.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 more specific safety hazards information, see Section 7.)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

定价： 590元 / 折扣价： 502 元 加购物车

4.1 Axially loaded tension specimens provide one of the most versatile methods of performing a stress-corrosion test because of the flexibility permitted in the choice of type and size of test specimen, stressing procedures, and range of stress levels.4.2 The uniaxial stress system is simple; hence, this test method is often used for studies of stress-corrosion mechanisms. This type of test is amenable to the simultaneous exposure of unstressed specimens (no applied load) with stressed specimens and subsequent tension testing to distinguish between the effects of true stress corrosion and mechanical overload (2). Additional considerations in regard to the significance of the test results and their interpretation are given in Sections 6 and 10.4.3 Wide variations in test results may be obtained for a given material and specimen orientation with different specimen sizes and stressing procedures. This consideration is significant especially in the standardization of a test procedure for interlaboratory comparisons or quality control.1.1 This practice covers procedures for designing, preparing, and using ASTM standard tension test specimens for investigating susceptibility to stress-corrosion cracking. Axially loaded specimens may be stressed quantitatively with equipment for application of either a constant load, constant strain, or with a continuously increasing strain.1.2 Tension test specimens are adaptable for testing a wide variety of product forms as well as parts joined by welding, riveting, or various other methods.1.3 The exposure of specimens in a corrosive environment is treated only briefly because other standards are being prepared to deal with this aspect. Meanwhile, the investigator is referred to Practices G35, G36, G37, and G44, and to ASTM Special Technical Publication 425 (1).21.4 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.1.5 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

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4.1 This test method may be used to confirm the stated zinc oxide and phosphorous acid content of zinc hydroxy phosphite pigment.1.1 This test method is intended for the determination of zinc oxide and phosphorous acid content of the pigment commercially known as zinc hydroxy phosphite. The zinc content is determined by ethylenediaminetetraacetate (EDTA) titration and calculated as zinc oxide (ZnO), while the phosphorus content is determined colorimetrically and calculated as phosphorous acid (H3PO3).1.2 The analytical procedures appear in the following order:  Sections Zinc oxide 6 through 8 Phosphorous acid 9 through 141.3 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.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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Measurement of bacterial densities is generally the first step in establishing a relationship between bacteria and other biochemical processes. It is known that the classical plate count procedure underestimates bacterial densities while the epifluorescence direct microscopic procedure more accurately depicts the total numbers of nonviable or dormant and viable cells in a water sample. The acridine-orange INT-formazan reduction technique provides information on the total concentrations of bacteria as well as that proportion which are actively respiring and thus involved in degradative processes.The acridine-orange INT-formazan reduction technique is both quantitative and precise.This procedure is ideal for enumerating both pelagic and epibenthic bacteria in all fresh water and marine environments.The process can be employed in survey studies to characterize the bacteriological densities and activities of environmental waters.1.1 This test method covers the detection and enumeration of aquatic bacteria by the use of an acridine-orange epifluorescence direct-microscopic counting procedure. This test method is applicable to environmental waters and potable waters.1.2 Certain types of debris and other microorganisms may fluoresce in acridine-orange stained smears.1.3 The procedure described requires a trained microbiologist or technician who is capable of distinguishing bacteria from other fluorescing bodies on the basis of morphology when viewed at higher magnifications.1.4 Use of bright light permits differentiation of single bacteria where reduced formazan is deposited at the polar ends.1.5 Approximately 104 cells/mL are required for detection by this test method.1.6 Minimal cell size which allows the detection of formazan deposits is represented by bacteria of 0.4 μm.21.7 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 does not purport to address 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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定价： 515元 / 折扣价： 438 元 加购物车

5.1 Bacterial populations, as part of the microbial community in aquatic systems are actively involved in nutrient cycling. The significance of these populations is often difficult to ascertain because of the presence of many physiological types. However, measurement of bacterial densities is usually the first step in trying to establish any relationship that might exist between bacteria and other biochemical processes.45.2 Acridine-orange epifluorescence direct-counting procedure cannot differentiate between viable and nonviable cells.5.3 This procedure cannot be used to convert directly the numbers to total carbon biomass because of the natural variations in bacterial cell size.5.4 The acridine-orange epifluorescence direct-microscopic count is both quantitative and precise.5.5 This procedure is ideal for enumerating both pelagic and epibenthic bacteria in all fresh water and marine environments.55.6 The process can be employed in survey activities to characterize the bacteriological densities of environmental waters.5.7 The procedure can also be used to estimate bacterial densities in cooling tower waters, process waters, and waters associated with oil drilling wells.1.1 This test method describes a procedure for detection and enumeration of aquatic bacteria by the use of an acridine-orange epifluorescence direct-microscopic counting procedure. It is applicable to environmental waters.1.2 Certain types of debris and other microorganisms may fluoresce in acridine orange-stained smears.1.3 The test method requires a trained microbiologist or technician who is capable of distinguishing bacteria from other fluorescing bodies on the basis of morphology when viewed at higher magnifications.21.4 Use of bright light permits differentiation of single bacteria where reduced formazan is deposited at the polar ends.1.5 Approximately 104 cells/mL are required for detection by this test method.21.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address 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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定价： 515元 / 折扣价： 438 元 加购物车

4.1 White zinc pigments find considerable use in white paints, and as such it is useful to formulators and users to be able to monitor the amounts of these pigments in whole paints. It is also of interest to raw material suppliers and paint producers to check the specifications of each pigment.1.1 These test methods cover procedures for the analysis of white zinc pigments.1.2 The analytical procedures appear in the following order:  SectionPreparation of Sample  6 Zinc OxideTotal Zinc, Using Diphenylamine as Internal Indicator  7 Total Zinc, Using Uranyl Acetate as External Indicator  8 Total Impurities  9 Total Sulfur 10Moisture and Other Volatile Matter 11Leaded Zinc OxideTotal Lead 12Total Zinc 13Total Sulfur 14Total Impurities 15Moisture and Other Volatile Matter 16Water-Soluble Salts 17Zinc SulfideZinc Oxide 18Zinc Sulfide 19Water-Soluble Salts 20Moisture and Other Volatile Matter 21Barium Sulfate 22Titanium Dioxide 231.3 The values stated in SI units are to be regarded as the 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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4.1 Monitoring Weighing Performance—This practice provides results in the form of control charts which measure the weighing capability at the time of the test. A series of tests at appropriate intervals will monitor balance performance over a period of time. A marked change from expected performance may result from a variety of causes including: maladjustment, damage, dirt, foreign material, and thermal disturbances. If the test results are to indicate future performance, any disturbances that occur exterior to the balance must be brought under control (2).4.2 Acceptance Tests—This practice may also be used as acceptance tests for new balances. For this purpose, the tests should be conducted under favorable, but not necessarily ideal, conditions. Since systematic error in the course of the zero and the course of the sensitivity may be caused by disturbances external to the balance, limits on these errors are not ordinarily prescribed in acceptance requirements.1.1 This practice covers testing procedures for evaluating the performance of single-arm balances required by ASTM standards.1.2 This practice is intended for but not limited to sensitivity ratios of 106 or better and on-scale ranges of 1000xd or more where d = reability either directly or by estimation.1.3 This practice can also be applied to other single-pan balances with mechanical weight changing of different capacities or sensitivities with appropriate test loads and calibration weights.NOTE 1: Mechanical balances of this type have largely been replaced by automatic electronic balances incorporating a variety of operational principles. Nevertheless, some single-pan mechanical balances are still manufactured and many older balances will remain in service for years to come. One type of automatic electronic balance, the so-called “hybrid,” bears considerable similarity to single-pan mechanical balances of the null type. (1)21.4 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.

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1.1 This specification covers concentric-lay-stranded conductors, made of round aluminum-alloy 5005-H19 (extra-hard) wires, for general use for electrical purposes. These conductors shall be constructed with a central core wire surrounded by one or more layers of helically laid wires (Explanatory Notes 1 and 2). 1.3 The values stated in inch-pound units are to be regarded as the standard, with the exception of resistivity. The SI equivalents of inch-pound units may be approximate. Note 1-The alloy and temper designations conform to ANSI H35.1. Aluminum-alloy 5005 corresponds to unified numbering system alloy A95505 in accordance with Practice E527.

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