GA/T 2000的本部分规定了人口迁移(流动)原因的代码。
本部分适用于治安管理信息数据的处理、交换和共享。

定价： 19元 / 折扣价： 17 元 加购物车

This specification covers one type of lightweight field and mobile shelter designed for transport by cargo truck, fixed or rotary winged aircraft, rail, and ship, as shelter, electrical equipment S-280/G. Core, adhesive, and sealer materials used in the construction of this item shall be in accordance with the density, compressive strength, shear strength, flammability, and water absorption requirements. Shock mounts shall be subjected to hardness, resilience, and depression-deflection tests to check for compliance with specified requirements. Construction properties shall comply with the cleaning, arc or resistance welding, lamination (impact resistance), vapor seal, interchangeability, riveting, finishing, marking, shelter gross weight, service integrity, and tightness preconditioning specifications. Environmental service conditions such as moisture resistance, rapid temperature changes, and thermal differential including thermal deformation and heat transfer shall be met. The shelter shall also conform to the requirements for transportability whether in rail or air transport, capability to withstand flat and rotational drops and simulated towing, lifting and towing eye casting hardness, and static door and roof access steps vertical loads for structural integrity. Tightness tests shall be conducted as well to verify shielding from air, door latch torque, light, electromagnetic interference, water, and fording.1.1 This specification covers one type of lightweight field and mobile shelter designed for transport by cargo truck, fixed or rotary winged aircraft, by rail, and ship, as Shelter, Electrical Equipment S-280/G (see 15.5).1.2 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.1.3 The following safety hazards caveat refers only to the test methods described in this specification. 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： 646元 / 折扣价： 550 元 加购物车

5.1 The data from this guide seldom, if ever, directly simulate thermal and pressure events in the processing, storage, and shipping of chemicals. However, the data obtained from this guide may be used, with suitable precautions, to predict the thermal and pressure hazards associated with processing, storage, and shipping of a chemical or mixture of chemicals after appropriate scaling of the data. This has been addressed in the literature (1-4) but is beyond the scope of this guide.5.2 This guide is suitable, under the proper conditions, for the investigation of the effects of catalyst, inhibitors, initiators, reaction atmospheres, materials of construction, or, if available, agitation (see 6.1.2).5.3 Interpretation of the time-temperature or time-pressure data may be possible for relatively simple systems through the use of suitable temperature-dependent kinetic theories such as the Arrhenius and Absolute Reaction Rate theories (5, 6).1.1 This guide covers suggested procedures for the operation of a calorimetric device designed to obtain temperature and pressure data as a function of time for systems undergoing a physicochemical change under nearly adiabatic conditions.1.2 This guide outlines the calculation of thermodynamic parameters from the time, temperature, and pressure data recorded by a calorimetric device.1.3 The assessment outlined in this guide may be used over a pressure range from full vacuum to the rated pressure of the reaction container and pressure transducer. The temperature range of the calorimeter typically varies from ambient to 500 °C, but also may be user specified (see 6.6).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. Specific safety precautions are outlined in 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

This specification covers industrial woven wire cloth (also known as, wire mesh), for general use including the separation of particles. Wire cloth can be produced in many thousands of combinations of size and shape of opening, wire diameter, and made of any primary metal or metal alloy wire that is suitable for weaving. E2016 presents standard terms and definitions, notes the normal range of specifications woven, and establishes technical requirements that include wire tolerances, mesh tolerance for double-crimp square mesh, width opening tolerances for space cloth, and delivery requirements. Developed based on obsolete Federal RR-W-360A, it is the only Standard that covers wire cloth as specified and manufactured according to mesh count.1.1 This specification covers industrial woven wire fabric, referred to as wire cloth, for general use including the separation of particles. Wire cloth can be made of any primary metal or metal alloy wire that is suitable for weaving. This specification does not apply to the following special types of wire cloth: filter cloth or dutch weave (see Appendix X1), fourdrinier and cylinder cloth, galvanized hardware cloth, insect wire screening, spiral weave wire cloth, testing sieve cloth, or welded wire cloth.1.2 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.1.3 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： 843元 / 折扣价： 717 元 加购物车

4.1 This guide is an educational tool for tank owners, operators, and other users and is not intended for use in certifying compliance with the Federal technical standards for underground storage tanks.4.2 The intent of this guide is to provide an overview of the general requirements. This guide is intended for users who are generally familiar with the requirements of 40 CFR Part 280. The user is advised that this guide does not contain the level of detail necessary to make the determination of whether specific equipment or services meet the detailed technical performance requirements of 40 CFR Part 280.4.3 This guide does not cover state and local requirements, that can be more stringent than the federal rules. Owners and operators are responsible for meeting federal, state, and, in some circumstances, local requirements. It is recommended that owners and operators familiarize themselves with these requirements as well.4.4 Owners or operators may use the sample checklist in Appendix X1 to assist them in determining operational conformance or they may develop their own checklist based upon this guide.4.5 This guide and accompanying appendixes are not intended to be used by state or local UST program authorities as a regulatory or administrative requirement for owners or operators. Use of this guide and appendixes by owners and operators is intended to be a voluntary educational tool for the purposes described in 4.1.1.1 This guide covers information for evaluating tank systems for operational conformance with the Federal technical standards (including the financial responsibility requirements) for underground storage tanks (USTs) found at 40 Code of Federal Register (CFR) Part 280.1.2 This guide does not address the corrective action requirements of 40 CFR Part 280.1.3 To the extent that a tank system is excluded or deferred from the federal regulations under Subpart A of 40 CFR Part 280, it is not covered by this guide.1.4 Local regulations may be more stringent than federal regulation and the reader should refer to the implementing agency to determine compliance.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： 646元 / 折扣价： 550 元 加购物车

5.1 The gauge is intended to provide a means for measuring image or detector unsharpness and basic spatial resolution of the image or detector as independently as practicable from the imaging system and contrast sensitivity limitations. When the duplex gauge is positioned directly on the film or the digital detector and not on the test object, then the determined unsharpness corresponds to the inherent film or detector unsharpness (Udetector) and the determined basic spatial resolution corresponds to the basic spatial detector resolution SRbdetector.NOTE 1: The gauge, described in ISO 19232-5, is equivalent to this standard in the dimensions and the evaluation procedure.5.2 Basis of Application 5.2.1 The following items are subject to contractual agreement between the parties using or referencing this practice.5.2.1.1 Personnel Qualification—Personnel performing examinations to this practice shall be qualified in accordance with NAS410, EN 4179, ANSI/ASNT CP 189, ISO 9712, or SNT-TC-1A and certified by the employer or certifying agency as applicable. Other equivalent qualification documents may be used when specified on the contract or purchase order. The applicable revision shall be the latest unless otherwise specified in the contractual agreement between parties.5.2.1.2 If specified in the contractual agreement, NDT agencies shall be qualified and evaluated as described in Specification E543. The applicable edition of Specification E543 shall be specified in the contract.1.1 This practice covers the design and basic use of a gauge used to determine the image unsharpness and the basic spatial resolution of film radiographs or of digital images taken with CR imaging plates, digital detector arrays, or radioscopic systems.1.2 This practice is applicable to radiographic and radioscopic imaging systems utilizing X-ray and gamma ray radiation sources.1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 The gauge described can be used effectively with tube voltages up to 600 kV.1.5 When using source voltages in the megavolt range, the results may not be completely satisfactory. The gauge may be used in the MV range, preferably for characterization of detectors without object.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

4.1 This guide deals with the difficult problem of benchmarking neutron transport calculations carried out to determine fluences for plant specific reactor geometries. The calculations are necessary for fluence determination in locations important for material radiation damage estimation and which are not accessible to measurement. Typically, the most important application of such calculations is the estimation of fluence within the reactor vessel of operating light water reactors (LWR) to provide accurate estimates of the irradiation embrittlement of the base and weld metal in the vessel. The benchmark procedure must not only prove that calculations give reasonable results but that their uncertainties are propagated with due regard to the sensitivities of the different input parameters used in the transport calculations. Benchmarking is achieved by building up data bases of benchmark experiments that have different influences on uncertainty propagation. For example, in simple vessel wall mockups where measurements are made within a simulated reactor vessel wall, the integral effect of uncertainties in iron cross sections (absorption and elastic and inelastic scattering) are dominant and have been bounded by the agreement between calculation and measurement. For more complicated integral benchmarks, other factors such as: uncertainties in the distribution of fission sources, geometry, the energy-dependent cross sections, and the angular scattering distribution for elemental components of major materials in the neutron field (such as water and iron) may all be important uncertainty contributors. This guide describes general procedures for using neutron fields with known characteristics to corroborate the calculational methodology and nuclear data used to derive neutron field information from measurements of neutron sensor response.4.2 The bases for benchmark field referencing are usually irradiations performed in standard neutron fields with well-known energy spectra and intensities. There are, however, less well known neutron fields that have been designed to mockup special environments, such as pressure vessel mockups in which it is possible to make dosimetry measurements inside of the steel volume of the “vessel”. When such mockups are suitably characterized, they are also referred to as benchmark fields. A benchmark is that against which other things are referenced, hence the terminology “to benchmark reference” or “benchmark referencing”. A variety of benchmark neutron fields, other than standard neutron fields, have been developed, or pressed into service, to improve the accuracy of neutron dosimetry measurement techniques. Some of these special benchmark experiments are discussed in this standard because they have identified needs for additional benchmarking or because they have been sufficiently documented to serve as benchmarks.4.3 One dedicated effort to provide benchmarks whose radiation environments closely resemble those found outside the core of an operating reactor was the Nuclear Regulatory Commission's Light Water Reactor Pressure Vessel Surveillance Dosimetry Improvement Program (LWR-PV-SDIP) (1)3. This program promoted better monitoring of the radiation exposure of reactor vessels and, thereby, provided for better assessment of vessel end-of-life conditions. An objective of the LWR-PV-SDIP was to develop improved procedures for reactor surveillance and document them in a series of ASTM standards (see Matrix E706). The primary means chosen for validating LWR-PV-SDIP procedures was by benchmarking a series of experimental and analytical studies in a variety of fields (see Guide E2005).1.1 This guide covers general approaches for benchmarking neutron transport calculations for pressure vessel surveillance programs in light water reactor systems. A companion guide (Guide E2005) covers use of benchmark fields for testing neutron transport calculations and cross sections in well controlled environments. This guide covers experimental benchmarking of neutron fluence calculations (or calculations of other exposure parameters such as dpa) in more complex geometries relevant to reactor pressure vessel surveillance. Particular sections of the guide discuss: the use of well-characterized benchmark neutron fields to provide an indication of the accuracy of the calculational methods and nuclear data when applied to typical cases; and the use of plant specific measurements to indicate bias in individual plant calculations. Use of these two benchmark techniques will serve to limit plant-specific calculational uncertainty, and, when combined with analytical uncertainty estimates for the calculations, will provide uncertainty estimates for reactor fluences with a higher degree of confidence.1.2 Although this guide and the companion guide, Guide E2005, are focused on power reactors, the principle of this guide is also applicable to non-power light water reactor pressure vessel surveillance programs.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 This guide is significant in that it addresses the data and information options of each component of the ecological risk assessment process, for both a screening and complex ERA. It outlines the data and information options while recognizing that an ecological risk assessment may be focused to achieve a particular stated goal. This guide is not intended to represent the views of the U.S. Environmental Protection Agency (USEPA), or any other regulatory agency, on data collection for ecological risk assessment.5.2 This guide is to be used by managers, scientists, and technical staff of contractors, industry, government agencies, and universities responsible for conducting ecological risk assessments at contaminated sites. It is to be used to guide data collection phases of the ecological risk assessment. It will assist in the development of the conceptual site model (see Guide E1689) and the identification of potential assessment and measurement endpoints (see Guide E1848 and US EPA’s Generic Ecological Assessment Endpoints, 2016 (5)). While it was written to assist in planning an ERA, the list also may be used in the review of a completed ERA.1.1 An ecological-risk assessment (ERA) is a process for organizing and analyzing data, information, assumptions, and uncertainties to evaluate the likelihood that adverse ecological effects might occur or are occurring as a result of a stressor. This guide is intended to assist remedial project teams, specifically ecological risk assessors, in identifying data and information options that may be used to perform a screening or complex ecological risk assessment (ERA) at a contaminated site.NOTE 1: While the intent of ERA is to evaluate risk (that is, the probability of adverse effects occurring in ecological receptors), there are no measures, statistics, or metrics that calculate or express risk explicitly. However, various metrics or indices, a common example being the hazard quotient, are used to inform risk assessments.1.2 The identification of data and information options for human health risk assessment is outside the scope of this guide.1.3 This guide is intended to provide a list for identifying data and information options and does not recommend a specific course of action for ERA activities.1.4 This guide addresses data and information options for the ecological risk assessment, not verification or long-term monitoring studies.1.5 This guide lists many of the common data and information options for ERA, but there may be others relevant for any particular site.1.6 This guide considers one component of an ERA, that is, identification of data and information options. Other ASTM guides have been developed, for example, Guides E1689 and E1848, and are being developed to cover other components of the risk assessment process.1.7 This guide does not provide information on how to perform any of the analytical procedures used to perform a risk assessment once data collection options are defined.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 / 折扣价： 502 元 加购物车

5.1 The only truly valid image quality indicator is a material or component, equivalent to the part being neutron radiographed, with a known standard discontinuity, inclusion, omission, or flaw (reference standard comparison part). The SI is designed to substitute for the reference standard, providing qualitative information on hole and gap sensitivity in a single unit. Fabrication in accordance with this practice is vital for accurate and consistent measurements.5.2 This practice shall be followed for the fabrication of all SIs to be used with Test Method E545 to determine image quality in direct thermal neutron radiography. Devices constructed to previous versions of this practice, or Test Method E545 for devices built between 1981 and 1991, can also be used.1.1 This practice covers the fabrication of Sensitivity Indicators (SI), which can be used to determine the relative quality of film radiographic images produced by direct, thermal neutron radiographic examination.1.2 Units—The values stated in inch-pound units are to be regarded as 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 This test method provides a means to evaluate the resistance to particle shedding of a thermal spray coating. Such particle shedding might occur during surgical insertion of an implant or as the result of micromotion of the implant after insertion.5.2 This abrasion test method may be useful for quality control analysis of a coating, and it can be used to evaluate the effects of processing variables, such as substrate preparation before coating, surface texture, coating technique variables, or postcoating treatments, any of which may influence the susceptibility of the coating to particle shedding.5.3 This abrasion test method is for flat plate-shaped specimens of a size sufficient that the wheels of the abrader do not leave the surface of the specimen. It is not recommended for devices with other shapes or sizes.1.1 This test method quantifies the abrasion resistance of metallic coatings produced by thermal spray processes on flat metallic surfaces. It is intended as a means of characterizing coatings used on surgical implants.1.2 This test uses the Taber Abraser,2 which generates a combination of rolling and rubbing to cause wear to the coating surface. Wear is quantified as cumulative weight loss.1.3 This test method is limited to flat, rigid specimens that do not react significantly with water and do not undergo a phase transformation or chemical reaction between room temperature and 100 °C in air.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

4.1 This practice is for use by designers and specifiers, regulatory agencies, owners and inspection organizations who are involved in the rehabilitation of conduits through the use of a resin-impregnated glass fiber tube, pulled in place through an existing pipe or conduit, subsequently inflated and then cured by a designed exposure to UV-light. As for any standard practice, modifications may be required for specific job conditions.1.1 This practice covers the procedures for the reconstruction of pipelines and conduits (4 in. to 72 in. (100 mm to 1830 mm) diameter) by the pulled-in place installation of a resin-impregnated, glass fiber tube into an existing pipe or conduit followed by its inflation with compressed air pressure (see Fig. 1) to expand it firmly against the wall surface of the host structure. The photo-initiated resin system in the tube is then cured by exposure to ultraviolet (UV) light. When cured, the finished cured-in-place pipe will be a continuous and tight fitting pipe within a pipe. This type of reconstruction process can be used in a variety of gravity flow applications such as sanitary sewers, storm sewers, process piping, electrical conduits, and ventilation systems.FIG. 1 UV Cured-In-Place Pipe Installation Method (Air/Steam)1.2 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.1.3 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： 646元 / 折扣价： 550 元 加购物车

5.1 It is well known that modern electrical appliances, incorporating electric motors that use carbon brushes for commutation, may emit aerosolized, particles into the surrounding environment. This test method determines the initial, fractional, filtration efficiency of a vacuum cleaner system, taking those emissions into consideration.5.2 For all vacuum cleaner systems tested, the total emissions of the unit, whatever the source(s), will be counted at each of the six particle size levels identified in the test procedure. This test method determines the initial, fractional filtration efficiency of a vacuum cleaner system, with or without the motor emissions mathematically removed in the calculation of efficiency.1.1 This test method may be used to determine the initial, fractional, filtration efficiency of household and commercial canister (tank-type), stick, hand-held, upright, and utility vacuum cleaner systems.1.1.1 Water-filtration vacuum cleaners which do not utilize a replaceable dry media filter located between the water-based filter and cleaning air exhaust are not included in this test method. It has been determined that the exhaust of these vacuum cleaners is not compatible with the specified discrete particle counter (DPC) procedure.1.2 The initial, fractional, filtration efficiencies of the entire vacuum cleaner system, at six discrete particle sizes (0.3, 0.5, 0.7, 1.0, 2.0, and >3 μm), is derived by counting upstream challenge particles and the constituent of downstream particles while the vacuum cleaner system is being operated in a stationary test condition.1.3 The vacuum cleaner system is tested either at the floor nozzle, the end of the hose (handle), or at the vacuum cleaner inlet (for handheld products) at the normal airflow rate.1.4 The vacuum cleaner system is tested with a new filter(s) installed, and with no preliminary dust loading. The fractional efficiencies determined by this test method shall be considered initial system filtration efficiencies.1.5 Neutralized potassium chloride (KCl) is used as the challenge media in this test method.1.6 One or two particle counters may be used to satisfy the requirements of this test method. If using one counter, flow control is required to switch between sampling the upstream and downstream air sampling probes.1.7 To efficiently utilize this test method, automated test equipment and computer data acquisition is recommended.1.8 Different sampling parameters, flow rates, and so forth, for the specific applications of the equipment and test procedure may provide equivalent results. It is beyond the scope of this test method to define those various possibilities.1.9 This test method is limited to the test apparatus, or its equivalent, as described in this document.1.10 This test method is not intended or designed to provide any measure of the health effects or medical aspects of vacuum cleaning.1.11 This test method is not intended or designed to determine the integrity of HEPA filtration assemblies used in vacuum cleaner systems employed in nuclear and defense facilities.1.12 The inch-pound system of units is used in this test method, except for the common usage of the micrometer, μm, for the description of particle size which is a SI unit.1.13 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.1.14 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

5.1 This test method is a procedure by which catalyst samples may be compared on an inter- or intra-laboratory basis. Catalyst producers and user should find this test method to be of value.1.1 This test method covers the determination of nickel and vanadium in equilibrium catalysts where the vanadium and nickel concentrations are greater than 50 and 25 mg/kg, respectively.1.2 Units—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

5.1 This test method is performance oriented for determining if, and to what degree, different liquids create biological activity on geotextile filters thereby reducing their flow capability. The use of the method is primarily oriented toward landfill leachates but can be performed with any liquid coming from a particular site or synthesized from a predetermined mixture of biological microorganisms.5.2 The test can be used to compare the flow capability of different types of geotextiles, drainage geocomposite, or soil/geotextile combinations.5.3 This test will usually take considerable time, for example, up to 1000 h, for the biological activity to initiate, grow, and reach an equilibrium condition. The curves resulting from the test are intended to indicate the in-situ behavior of a geotextile or soil/geotextile filter.5.4 The test specimen can be incubated under unsaturated drained conditions between readings, or kept saturated at all times. The first case allows for air penetration into the flow column and thus aerobic conditions. The second case can result in the absence of air; thus it may simulate anaerobic conditions.5.5 The flow rate can be determined using either a constant head test procedure or on the basis of a falling head test procedure. In either case, the flow column containing the geotextile or soil/geotextile is the same; only the head control devices change.NOTE 1: It has been found that once biological clogging initiates, constant head tests often pass inadequate quantities of liquid to accurately measure. It thus becomes necessary to use falling head tests, which can be measured based on time of movement of a relatively small quantity of liquid between two designated points on a clear plastic standpipe.5.6 If the establishment of an unacceptably high degree of clogging is seen in the flow rate curves, the device allows for back flushing with water or with water containing a biocide.5.7 The resulting flow rate curves are intended for use in the design of full-scale geotextile, drainage geocomposite, or soil/geotextile filtration systems and possible remediation schemes in the case of landfill leachate collection and removal systems.1.1 This test method is used to determine the potential for, and relative degree of, biological growth which can accumulate on geotextile, drainage geocomposites, or geotextile/soil filters.1.2 This test method uses the measurement of flow rates over an extended period of time to determine the amount of clogging.1.3 This test method can be adapted for unsaturated as well as saturated conditions.1.4 This test method can use constant head or falling head measurement techniques.1.5 This test method can also be used to give an indication as to the possibility of back flushing, biocide treatment, or both, for remediation purposes if biological clogging does occur.1.6 The values in SI units are to be regarded as the standard. The values provided in inch-pound units are for information only.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 / 折扣价： 502 元 加购物车

3.1 This test method is used to measure the surface area of precipitated, hydrated silicas that is available to the nitrogen molecule using the multipoint (B. E. T.) method. Single point nitrogen surface area is measured in accordance with the Test Methods D5604.3.2 Solids adsorb nitrogen, and under specific conditions, the adsorbed molecules approach a monomolecular layer. The quantity in this hypothetical monomolecular layer is calculated using the BET equation. Combining this with the area occupied by the nitrogen molecule yields the total surface area of the solid.3.3 This test method measures the estimated quantity of nitrogen in the monomolecular layer by adsorption at liquid nitrogen temperature and at several (at least five) partial pressures of nitrogen.3.4 Before a surface area determination can be made it is necessary that the silica be stripped of any material which may already be adsorbed on the surface. The stripping of adsorbed foreign material eliminates two potential errors. The first error is associated with the weight of the foreign material. The second error is associated with the surface area that the foreign material occupies.1.1 This test method covers a procedure which is used to measure the surface area of precipitated hydrated silicas by the conventional Brunauer, Emmett, and Teller (BET)2 theory of multilayer gas adsorption behavior using multipoint determinations, similar to that used for carbon black in Test Method D6556. This test method specifies the sample preparation and treatment, instrument calibrations, required accuracy and precision of experimental data, and calculations of the surface area results from the obtained data.1.2 This test method is used to determine the nitrogen surface area of precipitated silicas with specific surface areas in the range of 10 to 500 m2/g.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. The minimum safety equipment should include protective gloves, sturdy eye and face protection, and means to deal safely with accidental mercury spills.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