定价： 2093元 / 折扣价： 1780 元

定价： 2183元 / 折扣价： 1856 元 加购物车

定价： 1177元 / 折扣价： 1001 元

定价： 819元 / 折扣价： 697 元

定价： 819元 / 折扣价： 697 元

5.1 This test method is useful for the analysis of total uranium in water following wet-ashing, as required, due to impurities or suspended materials in the water.1.1 This test method covers the determination of total uranium, by mass concentration, in water within the calibrated range of the instrument, 0.1 μg/L or greater. Samples with uranium mass concentrations above the laser phosphorimeter dynamic range are diluted to bring the concentration to a measurable level.1.2 This test method was used successfully with reagent water. It is the user’s responsibility to ensure the validity of this test method for waters of untested matrices.1.3 The values stated in SI units are to be regarded as the 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.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 All S/H systems change with time and use. Therefore, a calibration procedure for evaluating the operation of an S/H system is desirable. This calibration procedure provides a method of obtaining an optimized interferometric image pattern associated with a given size anomaly.5.2 The use of straining blocks as calibration devices provides a means for ensuring the continued optimal performance of the S/H system. Straining blocks can also be used to compare performance of S/H systems in different facilities.5.3 At not greater than a three (3) month interval the S/H system shall be calibrated following the procedures described in this practice. When necessary, adjustments, repairs, or modifications shall be made to the S/H system until it is able to observe, in the same image, all anomalies of size within the range of interest contained in the straining blocks.1.1 This practice describes the construction and use of a calibration device for demonstrating the anomaly detection capability of interferometric laser imaging nondestructive tire inspection system. A common practice within the industry is to refer to these systems as shearographic/holographic (S/H) systems.1.2 This standard practice applies to S/H systems that are used for evaluating the structural integrity of pneumatic tires, (for example, presence or absence of anomalies within the tire).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 H2S measurements in natural gas are performed to ensure concentrations satisfy gas purchase contract criteria and to prevent pipeline and associated component corrosion.5.2 Using TDLAS for the measurement of H2S in natural gas enables a high degree of selectivity with minimal interference from common constituents in natural gas streams. The TDLAS analyzer can detect changes in concentration with a relatively rapid response compared to other methods so that operators may take swift action when designated H2S concentrations are exceeded.5.3 Primary applications covered in this test method are listed in 5.3.1 and 5.3.2. Each application may have differing requirements and methods for gas sampling. Additionally, different natural gas applications may require unique spectroscopic considerations.5.3.1 Raw natural gas is found in production, gathering sites, and inlets to gas-processing plants characterized by potentially high levels of water (H2O), carbon dioxide (CO2), H2S, and heavy hydrocarbons. Gas-conditioning plants and skids are normally used to remove H2O, CO2, H2S, and other contaminants.5.3.2 High-quality “sales gas” is found in transportation pipelines, natural gas distribution (utilities), and natural gas power plant inlets. The gas is characterized by a very high percentage of methane (90 to 100 %) with small quantities of other hydrocarbons and trace levels of contaminants.1.1 This test method is for the online determination of hydrogen sulfide (H2S) in natural gas using tunable diode laser absorption spectroscopy (TDLAS) analyzers also known as a “TDL analyzers.” The particular wavelength for H2S measurement varies by manufacturer, typically between 1000 and 10 000 nm with an individual laser having a tunable range of less than 10 nm. The H2S concentration ranges can be anywhere from 0-5  ppm(v) to 0-90 % by volume.1.2 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. TDLAS analyzers inherently output concentrations in unitless molar ratios such as ppm(v).NOTE 1: Weight-per-volume units such as milligrams or grains of H2S per cubic foot or cubic meter can be derived from ppm(v) at “standard conditions” or standard temperature and pressure.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

1.1 Scope IEC 60825-1 is applicable to safety of laser products. For convenience it is divided into three separate sections: Section One (General) and the annexes; Section Two (Manufacturing requirements); and Section Three (User's guide ). A laser

定价： 1229元 / 折扣价： 1045 元

5.1 This guide provides a means of using an LD instrument to obtain a droplet size distribution from a spray in gas co-flow that approximates a flux-sensitive sample.45.2 In many sprays, the experimenter shall account for spatial segregation of droplets by size. This guide provides a means of spatial averaging the droplet distribution.5.3 The results obtained will be statistical in nature and refer to the time average of droplet size distribution of the entire spray.5.4 This guide is used to calibrate a spray generation device to produce a desired droplet size distribution under prespecified environmental and co-flow conditions or characterize an unknown spray while minimizing the uncertainty in the measurement.1.1 The purpose of this guide is to define a test procedure for applying the laser diffraction (LD) method to estimate an average droplet size distribution that characterizes the flux of liquid droplets produced by a specified spray generation device under specified gas co-flow conditions using a specified liquid. The intended scope is limited to artificially generated sprays with high speed co-flow. The droplets are assumed to be in the size range of 1 to 2000 µm in diameter and occur in sprays that are contained within a volume as small as a few cubic centimetres or as large as a cubic metre. The droplet sizes are assumed to be distributed non-uniformly within the spray volume.1.2 This guide is intended primarily to guide measurement of performance of nozzles and atomizers using LD instruments.1.3 Non-uniform sprays require measurements across the entire spray cross section or through several chords providing a representative sample of the overall spray cross section. The aim of multiple-chord measurements is to obtain a single droplet size distribution that characterizes the whole spray rather than values from a single chordal measurement.1.4 Use of this guide requires that the instrument does not interfere with spray production and does not significantly impinge upon or disturb the co-flow of gas and the spray. This technique is, therefore, considered non-intrusive.1.5 The computation of droplet size distributions from the light-scattering distributions is done using Mie scattering theory or Fraunhofer diffraction approximation. The use of Mie theory accounts for light refracted through the droplet and there is a specific requirement for knowledge of both real (refractive) and imaginary (absorptive) components of the complex index of refraction. Mie theory also relies on an assumption of droplet homogeneity. The Fraunhofer diffraction approximation does not account for light refracted through the droplet and does not require knowledge of the index of refraction.1.6 The instruments shall include data-processing capabilities to convert the LD scattering intensities into droplet size distribution parameters in accordance with Practice E799 and Test Method E1260.1.7 The spray is visible and accessible to the collimated beam produced by the transmitter optics of the LD instrument. The shape and size of the spray shall be contained within the working distance of the LD system optics as specified by the instrument manufacturer.1.8 The size range of the LD optic should be appropriate to the spray generation device under study. For example, the upper bound of the smallest droplet size class reported by the instrument shall be not more than 1/4 the size of DV0.1.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.11 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 test method permits a user to compare the performance of an instrument to the tolerance limit specifications stated by a manufacturer and to verify that an instrument is suitable for continued routine use. It also provides for generation of calibration data on a periodic basis, forming a database from which any changes in the performance of the instrument will be evident.4.2 This test method for the calibration verification of laser diffraction particle sizing instruments is suitable for acceptance testing of laser diffraction instruments so long as current estimates of the bias (see Section 11) and the between-laboratory precision of the test method (see Section 10) are acceptably small relative to typical laser diffraction instrument accuracy specifications; see Practice D3244.1.1 This test method describes a procedure necessary to permit a user to easily verify that a laser diffraction particle sizing instrument is operating within tolerance limit specifications, for example, such that the instrument accuracy is as stated by the manufacturer. The recommended calibration verification method provides a decisive indication of the overall performance of the instrument at the calibration point or points, but it is specifically not to be inferred that all factors in instrument performance are verified. In effect, use of this test method will verify the instrument performance for applications involving spherical particles of known refractive index where the near-forward light scattering properties are accurately modeled by the instrument data processing and data reduction software. The precision and bias limits presented herein are, therefore, estimates of the instrument performance under ideal conditions. Nonideal factors that could be present in actual applications and that could significantly increase the bias errors of laser diffraction instruments include vignetting4 (that is, where light scattered at large angles by particles far away from the receiving lens does not pass through the receiving lens and therefore does not reach the detector plane), the presence of nonspherical particles, the presence of particles of unknown refractive index, and multiple scattering.1.2 This test method shall be used as a significant test of the instrument performance. While the procedure is not designed for extensive calibration adjustment of an instrument, it shall be used to verify quantitative performance on an ongoing basis, to compare one instrument performance with that of another, and to provide error limits for instruments tested.1.3 This test method provides an indirect measurement of some of the important parameters controlling the results in particle sizing by laser diffraction. A determination of all parameters affecting instrument performance would come under a calibration adjustment procedure.1.4 This test method shall be performed on a periodic and regular basis, the frequency of which depends on the physical environment in which the instrumentation is used. Thus, units handled roughly or used under adverse conditions (for example, exposed to dust, chemical vapors, vibration, or combinations thereof) shall undergo a calibration verification more frequently than those not exposed to such conditions. This procedure shall be performed after any significant repairs are made on an instrument, such as those involving the optics, detector, or electronics.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 problems, 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： 646元 / 折扣价： 550 元 加购物车

This document specifies the features of laser-based powder bed fusion of metals (PBF-LB/M) and provides detailed design recommendations.Some of the fundamental principles are also applicable to other additive manufacturing (AM) processes, provided that due consideration is given to the process-specific features.This document also provides a state of the art review of design guidelines associated with the use of powder bed fusion (PBF) by bringing together relevant knowledge about this process and by extending the scope of ISO/ASTM 52910.

定价： 646元 / 折扣价： 550 元 加购物车

This specification covers the standard requirements for laser beam welded, black plain end steel pipe for use in the conveyance of fluids under pressure. Dimensions and weight [mass] per unit length of pipes with designated NPS sizes and specified nominal wall thickness shall be given. Heat and product analysis shall be performed wherein steel shall conform to the required chemical composition for carbon, sulfur, and phosphorus. The steel shall conform to the required tensile properties such as minimum and maximum yield strength. The following tests shall be conducted, namely: Charpy V-notch test; weld ductility test; and hydrostatic test.1.1 This specification covers laser beam welded, black, plain end steel pipe for use in the conveyance of fluids under pressure. Pipe in sizes NPS 1 to 26, inclusive, with nominal wall thickness 0.750 in. [19.1 mm] or less, as given in Table 1, is included. Pipe having other dimensions, in this size range, may be furnished provided such pipe complies with all other requirements of this specification.1.2 It is intended that the pipe be capable of being circumferentially welded in the field when welding procedures in accordance with the requirements of the applicable pipeline construction code are used.1.3 The values stated in either inch-pound units or in SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values in each system are not exact equivalents: therefore, each system is to be used independently of the other, without combining values in any way.1.4 The following precautionary statement pertains to the test method portion, Section 14, of 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 and health practices and determine the applicability of regulatory limitations prior to use.

定价： 0元 / 折扣价： 0 元

This document specifies the features of laser-based powder bed fusion of polymers (LB-PBF-P) and provides detailed design recommendations. Some of the fundamental principles are also applicable to other additive manufacturing (AM) processes, provided that due consideration is given to process-specific features. This document also provides a state-of-the-art review of design guidelines associated with the use of powder bed fusion (PBF) by bringing together relevant knowledge about this process and by extending the scope of ISO/ASTM 52910.

定价： 525元 / 折扣价： 447 元 加购物车

1.1 This document provides guidance and recommendations for the qualification of polymeric materials intended for laser-based powder bed fusion of polymers (PBF-LB/P). The parameters and recommendations presented in this document relate mainly to the material polyamide 12 (PA12), but references are also made to polyamide 11 (PA11). The parameters and recommendations set forth herein cannot be applicable to other polymeric materials.1.2 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： 562元 / 折扣价： 478 元 加购物车