定价： 646元 加购物车

定价： 646元 加购物车

定价： 571元 加购物车

定价： 646元 加购物车

定价： 260元 / 折扣价： 221 元 加购物车

5.1 This test method is useful for measuring recreational water quality and chlorinated wastewaters, although it can be used for any water suspected of contamination by fecal wastes of warm-blooded animals. The significance of finding E. coli in recreational water samples, especially samples obtained from fresh recreational waters, is that there is a risk of gastrointestinal illness, directly related to the E. coli density, associated with swimming.55.2 Since small or large volumes of water or dilutions thereof can be analyzed by the MF technique, a wider range of levels of E. coli in water can be detected and enumerated than with other methods.1.1 This test method describes a membrane filter (MF) procedure for the detection and enumeration of Escherichia coli, a bacterium found exclusively in the feces of humans and other warm-blooded animals. The presence of these microorganisms in water is an indication of fecal pollution and the possible presence of enteric pathogens. These bacteria are found in water and wastewater in a wide range of densities. The detection limit of this procedure is one colony forming unit (CFU) per volume filtered.1.2 This test method has been used successfully with temperate fresh and marine ambient waters, and wastewaters. It is the user’s responsibility to ensure the validity of this test method for waters of other types.1.3 The values stated in SI units are to be regarded as 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. For specific hazard statements, see Section 9.1.5 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 加购物车

5.1 This practice allows the user to compute the true hydraulic efficiency of a pumped well in a confined aquifer from a constant rate pumping field test. The procedures described constitute the only valid method of determining well efficiency. Some practitioners have confused well efficiency with percentage of head loss associated with laminar flow, a parameter commonly determined from a step-drawdown test. Well efficiency, however, cannot be determined from a step-drawdown test but only can be determined from a constant rate test.5.2 Assumptions: 5.2.1 Control well discharges at a constant rate, Q.5.2.2 Control well is of infinitesimal diameter.5.2.3 Data are obtained from the control well and, if available, a number of observation wells.5.2.4 The aquifer is confined, homogeneous, and extensive. The aquifer may be anisotropic, and if so, the directions of maximum and minimum hydraulic conductivity are horizontal and vertical, respectively.5.2.5 Discharge from the well is derived exclusively from storage in the aquifer.5.3 Calculation Requirements—For the special case of partially penetrating wells, application of this practice may be computationally intensive. The function fs shown in Eq 6 should be evaluated using arbitrary input parameters. It is not practical to use existing, somewhat limited, tables of values for fs and, because this equation is rather formidable, it may not be tractable by hand. Because of this, it is assumed the practitioner using this practice will have available a computerized procedure for evaluating the function fs. This can be accomplished using commercially available mathematical software including some spreadsheet applications. If calculating fs is not practical, it is recommended to substitute the Kozeny equation for the Hantush equation as previously described.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.NOTE 2: Commercially available software is available for the calculating, graphing, plotting, and analyses of this practice. The user is responsible for verifying the correctness of the formulas, graphs, plots and analyses of the software.1.1 This practice describes an analytical procedure for determining the hydraulic efficiency of a production well in a confined aquifer. It involves comparing the actual drawdown in the well to the theoretical minimum drawdown achievable and is based upon data and aquifer coefficients obtained from a constant rate pumping test.1.2 This analytical practice is used in conjunction with the field procedure, Test Method D4050.1.3 The values stated in inch-pound units are to be regarded as standard, except as noted below. The values given in parentheses are mathematical conversions to SI units, which are provided for information only and are not considered standard. The reporting of results in units other than inch-pound shall not be regarded as nonconformance with this standard.1.3.1 The gravitational system of inch-pound units is used when dealing with inch-pound units. In this system, the pound (lbf) represents a unit of force (weight), while the unit for mass is slugs.1.4 Limitations—The limitations of the technique for determination of well efficiency are related primarily to the correspondence between the field situation and the simplifying assumption of this practice.1.5 All observed and calculated values shall conform to the guidelines for significant digits and round established in Practice D6026, unless superseded by this standard.1.5.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported date to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis method for engineering design.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.7 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.1.8 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 加购物车

5.1 The Device record includes information about how the heat butt fusion joint was made (heater temperature, pressures and times for the heating, fusion and cooling steps) and other important information about the process, job, equipment used, etc. The Device record is compared to the specified heat butt fusion procedure parameters to determine if the procedure was followed correctly. For comparison purposes, a graph of time versus pressure is generated from the data record to show pressure changes that occur during the butt fusion process. Comparing the time versus pressure graph to the steps in the procedure helps determine that the procedure parameters were observed, (Note 1). (See Appendix X1.) These records may be downloaded from the device and stored.5.2 When used in conjunction with manually-operated machines, the Device records information about the procedure used, the operator, the equipment, and the piping material. The Device may capture photographs of the set up (alignment and cleanliness) as well as the completed fusion bead. These records may be downloaded from the device and stored.NOTE 1: The Device cannot show all aspects of the heat butt fusion conditions (such as wind, cold weather, blowing dust and sand, etc.) and does not preclude periodic joint testing as described in the applicable fusion standard or procedure.1.1 This practice specifies the data recording information that is recorded, when data recording equipment is used, on heat butt fusion joints in a plastic piping system in order to compare the procedure used in making the joint to the heat butt fusion joining procedure specified. This practice is suitable for use with all heat butt fusion joining procedures such as Practice F2620, Specification F3372, Specification F2945 international standards or other qualified procedures. This practice primarily applies to hydraulically operated heat butt fusion machines and can be utilized for documenting heat butt fusion joints completed with manually-operated fusion machines.1.2 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title means only that the document has been approved through the ASTM consensus process.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 加购物车

定价： 646元 加购物车

定价： 590元 加购物车

定价： 712元 加购物车

5.1 Assumptions: 5.1.1 Well discharges at a constant rate, Q.5.1.2 Well is of infinitesimal diameter and fully penetrates the aquifer, that is, the well is open to the full thickness of the aquifer.5.1.3 The nonleaky aquifer is homogeneous, isotropic, and areally extensive. A nonleaky aquifer receives insignificant contribution of water from confining beds.5.1.4 Discharge from the well is derived exclusively from storage in the aquifer.5.1.5 The geometry of the assumed aquifer and well conditions are shown in Fig. 1.5.2.3 Application of Theis Nonequilibrium Method to Unconfined Aquifers: 5.2.3.1 Although the assumptions are applicable to confined conditions, the Theis solution may be applied to unconfined aquifers if drawdown is small compared with the saturated thickness of the aquifer or if the drawdown is corrected for reduction in thickness of the aquifer and the effects of delayed gravity yield are small.5.2.3.2 Reduction in Aquifer Thickness—In an unconfined aquifer, dewatering occurs when the water levels decline in the vicinity of a pumping well. Corrections in drawdown need to be made when the drawdown is a significant fraction of the aquifer thickness as shown by Jacob (8). The drawdown, s, needs to be replaced by s′, the drawdown that would occur in an equivalent confined aquifer, where:5.2.3.3 Gravity Yield Effects—In unconfined aquifers, delayed gravity yield effects may invalidate measurements of drawdown during the early part of the test for application to the Theis method. Effects of delayed gravity yield are negligible in partially penetrating observation wells at a distance, r, from the control well, where:after the time, t, as given in the following equation from Neuman (9):where:Sy   =   the specific yield.For fully penetrating observation wells, the effects of delayed yield are negligible at the distance, r, in Eq 11 after one tenth of the time given in the Eq 12.NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.NOTE 3: The injection of water into an aquifer may be regulated or require regulatory approvals. Withdrawal of contaminated waters may require that the removed water be properly treated prior to discharge.1.1 This practice covers an analytical procedure for determining transmissivity and storage coefficient of a nonleaky confined aquifer under conditions of radial flow to a fully penetrating well of constant flux. This practice is a shortcut procedure used to apply the Theis nonequilibrium method. The Theis method is described in Practice D4106.1.2 This practice, along with others, is used in conjunction with the field procedure given in Test Method D4050.1.3 Limitations—The limitations of this practice are primarily related to the correspondence between the field situation and the simplifying assumptions of this practice (see 5.1). Furthermore, application is valid only for values of u less than 0.01 (u is defined in Eq 2, in 8.6).1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.1.4.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analytical methods for engineering design.1.5 Units—The values stated in either SI Units or inch-pound units are to be regarded separately as standard. The values in each system may not be exact equivalents; therefore each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. Reporting of results in units other than SI shall not be regarded as nonconformance with this practice.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.7 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.1.8 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 加购物车

5.1 This practice is one of several available for determining vertical anisotropy ratio. Among other available methods are Weeks ((5); see Practice D5473/D5473M), that relies on distance-drawdown data, and Way and McKee (6), that utilizes time-drawdown data. An important restriction of the Weeks distance-drawdown method is that the observation wells need to have identical construction (screened intervals) and two or more of the observation wells need to be located at a distance from the pumped well beyond the effects of partial penetration. The procedure described in this practice general distance-drawdown method, in that it works in theory for most observation well configurations incorporating three or more wells, provided some of the wells are within the zone where flow is affected by partial penetration.5.2 Assumptions: 5.2.1 Control well discharges at a constant rate, Q.5.2.2 Control well is of infinitesimal diameter and partially penetrates the aquifer.5.2.3 Data are obtained from a number of partially penetrating observation wells, some screened at elevations similar to that in the pumped well and some screened at different elevations.5.2.4 The aquifer is confined, homogeneous and areally extensive. The aquifer may be anisotropic, and, if so, the directions of maximum and minimum hydraulic conductivity are horizontal and vertical, respectively.5.2.5 Discharge from the well is derived exclusively from storage in the aquifer.5.3 Calculation Requirements—Application of this method is computationally intensive. The function, fs, shown in (Eq 4) should be evaluated numerous times using arbitrary input parameters. It is not practical to use existing, somewhat limited, tables of values for fs and, because this equation is rather formidable, it may not be easily tractable by hand. Because of this, it is assumed the practitioner using this will have available a computerized procedure for evaluating the function fs. This can be accomplished using commercially available mathematical software including some spreadsheet applications, or by writing programs. (7)NOTE 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.NOTE 3: Most fractured (unconfined) aquifers, even noncarbonates, will have some form of convergent flow to master fissures or channels (Worthington et al., 2016). A relationship is known to occur in carbonates where potentiometric troughs correspond with sub-surface conduits or channels (Quinlan and Ewers, 1989).NOTE 4: Commercially available software is available for the calculating, graphing, plotting, and analyses of this practice. The user should verify the correctness of the formulas, graphs, plots and analyses of the software.1.1 This practice covers an analytical procedure for determining the transmissivity, storage coefficient, and ratio of vertical to horizontal hydraulic conductivity of a confined aquifer using observation well drawdown measurements from a constant-rate pumping test. This practice uses data from a minimum of four partially penetrating, recommended to be positioned observation wells around a partially penetrating control well.1.2 The analytical procedure is used in conjunction with the field procedure in Test Method D4050.1.3 Limitations—The limitations of the technique for determination of the horizontal and vertical hydraulic conductivity of aquifers are primarily related to the correspondence between the field situation and the simplifying assumption of this practice.1.4 Units—The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are mathematical conversions, which are provided for information purposes only and are not considered standard. The reporting of results in units other than inch-pound shall not be regarded as nonconformance with this standard.1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026, unless superseded by this standard.1.6 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objective; and it is common practice to increase or reduce the significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis method or engineering design.1.7 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.8 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.1.9 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 加购物车

This practice covers procedures that can be followed to safeguard against the possible embrittlement of steel hot-dip galvanized after fabrication, and outlines test procedures for detecting embrittlement. Conditions of fabrication may induce a susceptibility to embrittlement in certain steels that can be accelerated by galvanizing. Open-hearth, basic-oxygen, and electric-furnace steels shall be used for galvanizing. Other materials that can be galvanized include continuous cast slabs, steel or iron castings, and wrought iron. The material shall undergo cold working and thermal treatment. Embrittlement of steel shapes, steel castings, threaded articles, and hardware items shall be tested using a bend test , a universal testing machine, or by means of a press with the load applied slowly, until fracture of the galvanized test specimen occurs.1.1 This practice covers procedures that can be followed to safeguard against the possible embrittlement of steel hot-dip galvanized after fabrication, and outlines test procedures for detecting embrittlement. Conditions of fabrication may induce a susceptibility to embrittlement in certain steels that can be accelerated by galvanizing. Embrittlement is not a common occurrence, however, and this discussion does not imply that galvanizing increases embrittlement where good fabricating and galvanizing procedures are employed. Where history has shown that for specific steels, processes and galvanizing procedures have been satisfactory, this history will serve as an indication that no embrittlement problem is to be expected for those steels, processes, and galvanizing procedures.1.2 This practice is applicable in either inch-pounds or SI units. Inch-pounds and SI units are not necessarily exact equivalents. Within the text of this practice and where appropriate, SI units are shown in brackets.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 加购物车

定价： 571元 加购物车