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定价： 481元 / 折扣价： 409 元 加购物车

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4.1 This practice permits an analyst to compare the performance of an NMR spectrometer for a particular test on any given day with the instrument's prior performance for that test. The practice can also provide sufficient quantitative performance information for problem diagnosis and solving. If complete information about how a test is carried out is supplied and sufficient replicates are collected to substantiate statistical relevance, the tests in this practice can be used to establish the setting and meeting of relevant performance specifications. This practice is not necessarily meant for the comparison of different instruments with each other, even if the instruments are of the same type and model. This practice is not meant for the comparison of the performance of different instruments operated under conditions differing from those specified for a particular test.1.1 This practice covers procedures for measuring and reporting the performance of Fourier-transform nuclear magnetic resonance spectrometers (FT-NMRs) using liquid samples.1.2 This practice is not directly applicable to FT-NMR spectrometers outfitted to measure gaseous, anisotropically structured liquid, semi-solid, or solid samples; those set up to work with flowing sample streams; or those used to make hyperpolarization measurements.1.3 This practice was expressly developed for FT-NMR spectrometers operating with proton resonance frequencies between 200 MHz and 1200 MHz.1.4 This practice is not directly applicable to continuous wave (scanning) NMR spectrometers.1.5 This practice is not directly applicable to instruments using single-sideband detection.1.6 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.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.

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5.1 This test method is one of those required to determine if the presence of a medical device may cause injury to individuals during an MR examination or in the MR environment. Other safety issues which should be addressed include, but may not be limited to: magnetically induced torque (see Test Method F2213) and radiofrequency (RF) heating (see Test Method F2182). The terms and icons in Practice F2503 should be used to mark the device for safety in the magnetic resonance environment.5.2 If the maximum magnetically induced displacement force for the specified magnetic field conditions (see Appendix X3) is less than the force on the device due to gravity (its weight), it is assumed that any risk imposed by the application of the magnetically induced force is no greater than any risk imposed by normal daily activity in the Earth’s gravitational field. This statement does not constitute an acceptance criterion; it is provided as a conservative reference point. It is possible that a greater magnetically induced displacement force can be acceptable and would not harm a patient or other individual in a specific case.NOTE 2: For instance, in the case of an implanted device that is or could be subjected to a magnetic displacement force greater than the force due to gravity, the location of the implant, surrounding tissue properties, and means of fixation within the body may be considered. For a non-implanted device with a magnetically induced force greater than the gravitational force, consideration should be given to mitigate the projectile risk which may include fixing or tethering the device or excluding it from the MR environment so that it does not become a projectile.5.3 The maximum static magnetic field strength and spatial field gradient vary for different MR systems. Appendix X3 provides guidance for calculating the allowable static magnetic field strength and spatial field gradient.5.4 This test method alone is not sufficient for determining if a device is safe in the MR environment.1.1 This test method covers the measurement of the magnetically induced displacement force produced by static magnetic field gradients (spatial field gradient) on medical devices and the comparison of that force to the weight of the medical device.1.2 This test method does not address other possible safety issues which include, but are not limited to: issues of magnetically induced torque, radiofrequency (RF) heating, induced heating, acoustic noise, interaction among devices, and the functionality of the device and the magnetic resonance (MR) system.1.3 This test method is intended for devices that can be suspended from a string. Devices which cannot be suspended from a string are not covered by this test method. The weight of the string from which the device is suspended during the test must be less than 1 % of the weight of the tested device.1.4 This test method shall be carried out in a horizontal bore MR system with a static magnetic field oriented horizontally and parallel to the MR system bore.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, 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

5.1 Magnetic resonance imaging is ideally suited to image MOM hip arthroplasty due to its superior soft tissue contrast, multiplanar capabilities and lack of ionizing radiation. MR imaging is the most accurate imaging modality for the assessment of peri-prosthetic osteolysis and wear-induced synovitis (19, 20).5.2 Before scanning a patient with a specific implant, the MR practitioner shall confirm that the device is MR Conditional and that the scan protocol to be used satisfies the conditions for safe scanning for the specific implant.5.3 This guide can be used to identify the following adverse events.5.3.1 Osteolysis—Magnetic resonance imaging is superior to conventional radiographs and computer tomography (CT) in the assessment of peri-prosthetic osteolysis and has been shown to be the most accurate method to locate and quantify the extent of peri-prosthetic osteolysis (19, 21). On MR imaging, osteolysis appears as well marginated intraosseous intermediate to slightly increased signal intensity lesions that contrast with the high signal intensity of the intramedullary fat. A characteristic line of low signal intensity surrounds the area of focal marrow replacement, distinguishing the appearance of osteolysis from tumoral replacement of bone or infection (22).FIG. 4 Coronal (left) and Axial (right) FSE Images of a Left MOM Hip ArthroplastyNOTE 1: There is focal osteolysis (white arrows) in the greater trochanter, which manifests as well-demarcated intermediate signal intensity, similar to that of skeletal muscle, replacing the normal high signal intensity fatty marrow. Images courtesy of Dr. Hollis Potter.5.3.2 Component Loosening—While the data are preliminary, MR imaging can identify circumferential bone resorption that may indicate component loosening. Loosening may result from osteolysis, circumferential fibrous membrane formation or poor osseous integration of a non-cemented component. On MR imaging, component loosening typically manifests as circumferential increased signal intensity at the metallic-bone or cement-bone interface on fat-suppressed techniques (20). The finding of circumferential fibrous membrane formation or osteolysis also indicates potential loosening; this is in contrast to a well-fixed component, with high signal intensity fatty marrow directly opposed to the implant interface.5.3.3 Wear-Induced Synovitis—Magnetic resonance imaging is the most useful imaging modality to assess the intracapsular burden of wear-induced synovitis surrounding MOM arthroplasty (23). Preliminary data indicate that the signal characteristics of the synovial response on MR imaging correlate with the type of wear-induced synovitis demonstrated on histology at revision surgery (24). Low signal intensity debris is suggestive of metallic debris on histology. Mixed intermediate and low signal debris correlate with the presence of mixed polymeric (polyethylene and/or polymethyl methacrylate) and metallic debris at histology. Magnetic resonance imaging can demonstrate decompression of synovitis or fluid into adjacent bursae, such as the iliopsoas or trochanteric bursa, which can present as soft tissue masses or with secondary nerve compression. On occasion, wear-induced synovitis can result in a chronic indolent pattern of erosion of the surrounding bone, even in the absence of focal osteolytic lesions (6).FIG. 5 Axial (left) and Coronal (right) FSE Images of a Left MOM Hip ArthroplastyNOTE 1: Wear-induced synovitis decompresses into the abductor musculature where there is low signal intensity debris (arrow), consistent with metallic debris. Images courtesy of Dr. Hollis Potter.5.3.4 Infection—In the setting of infection, the synovium often demonstrates a hyperintense, lamellated appearance with adjacent extracapsular soft tissue edema. These appearances help to distinguish the synovial pattern of infection from wear-induced synovitis, although aspiration is still required for definitive diagnosis (22). The presence of a soft tissue collection, draining sinus or osteomyelitis further supports the diagnosis of infection on MR imaging.FIG. 6 Axial FSE (left) and Inversion Recovery (right) Images of a Right MOM Hip AthroplastyNOTE 1: There is a lamellated synovitis (black arrow) with adjacent extracapsular soft tissue edema (white arrow). Infection was confirmed at subsequent aspiration. Images courtesy of Dr. Hollis Potter.5.3.5 Adverse Local Tissue Response—Adverse local tissue reactions can manifest as synovitis, bursitis, osteolysis and cystic or solid masses adjacent to the arthroplasty, which may be termed pseudotumors (19, 20). ALTR can also include the histopathologic feature of aseptic lymphocytic vasculitis-associated lesions (ALVAL), which can be confirmed at histology. A relatively common appearance of joints with ALVAL is expansion of the capsule with homogenous high signal fluid interspersed with intermediate signal intensity foci. More recent studies suggest that maximum synovial thickness and the presence of more solid synovial deposits highly correlate with tissue damage at revision surgery and necrosis at histologic inspection (15).FIG. 7 Axial FSE Image in a Right MOM Hip ArthroplastyNOTE 1: Fig. 7 demonstrates a large collection of fluid in the trochanteric bursa (arrow), which communicates with the hip joint via a dehiscence in the posterior pseudocapsule (not shown in these images). The fluid is high signal with fine intermediate signal intensity debris. A high ALVAL score was confirmed on histology at revision surgery. Images courtesy of Dr. Hollis Potter.FIG. 8 Axial FSE Image in a Right MOM Hip Resurfacing ArthroplastyNOTE 1: Fig. 8 demonstrates expansion of the pseudocapsule with fluid signal intensity decompressing into the trochanteric bursa. The pseudocapsule is thickened and of intermediate signal intensity (black arrows). There is additional solid extracapsular disease anteriorly (white arrow). At revision surgery, a mixed picture of ALVAL and metallosis was seen.5.3.6 Modular Taper Associated ALTR—MRI can accurately describe ALTR attributed to tribocorrosion in modular femoral neck total hip arthroplasty. MRI characteristics, particularly maximal synovial thickness and synovitis volume, can predict histologic severity (22, 23). In addition, intra-capsular ALTR around either resurfacing MOM arthroplasty or around the trunnion in MOM THA may be obscured if 3D-MSI techniques are not utilized due to the susceptibility artifact. High-bandwidth FSE or FSE with view-angle tilt are not sufficient.NOTE 1: Modular taper ALTR may occur in non-metal-on-metal implants as well as in metal-on-metal arthroplasty.1.1 This guide describes the recommended protocol for magnetic resonance imaging (MRI) studies of patients implanted with metal-on-metal (MOM) devices to determine if the periprosthetic tissues are likely to be associated with an adverse local tissue reaction (ALTR). Before scanning a patient with a specific implant, the MR practitioner shall confirm that the device is MR Conditional and that the scan protocol to be used satisfies the conditions for safe scanning for the specific implant. This guide assumes that the MRI protocol will be applied to MOM devices while they are implanted inside the body. It is also expected that standardized MRI safety measures will be followed during the performance of this scan protocol.1.2 This guide covers the clinical evaluation of the tissues surrounding MOM hip replacement devices in patients using MRI. This guide is applicable to both total and resurfacing MOM hip systems.1.3 The protocol contained in this guide applies to whole body magnetic resonance equipment, as defined in section 201.3.239 of IEC 60601-2-33, Ed. 3.2, with a whole body radiofrequency (RF) transmit coil as defined in section 201.3.240. The RF coil should have circulary polarized RF excitation (also commonly referred to as quadrature excitation) as defined in section 201.3.249 of IEC 60601-2-33, Ed. 3.2..1.4 The values stated in SI units are to be regarded as 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. The user may consider all precautions and warnings provided in the MR system and hip implant labeling prior to determining the applicability of these protocols.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.

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定价： 345元 / 折扣价： 294 元 加购物车

5.1 In-plant Oil Analysis—The particular five-part integrated tester practice is primarily used by plant maintenance personnel desiring to perform on-site analysis of as-received and in-service lubricating oils.5.2 Detect Common Lubrication Problems—The software application interprets data from integration of multiple sensing technologies to detect common lubrication problems from inadvertent mixing of dissimilar lubricant viscosity grades and from particulate or moisture contamination. The redundant views of ferrous particulates (sensor 2), all particulates larger than 4 μm (sensor 3), and all solid particulates larger than filter patch pore size (patch maker) provides screening for oil wetted mechanical system failure mechanisms from incipient to catastrophic stages.5.3 Supported by Off-Site Lab Analysis—The particular five-part integrated tester is normally used in conjunction with an off-site laboratory when exploring the particular nature of an alarming oil sample. An off-site laboratory should be consulted for appropriate additional tests.1.1 This practice covers procedures for analysis of in-service lubricant samples using a particular five-part (dielectric permittivity, time-resolved dielectric permittivity with switching magnetic fields, laser particle counter, microscopic debris analysis, and orbital viscometer) integrated tester to assess machine wear, lubrication system contamination, and lubricant dielectric permittivity and viscosity. Analyzed results trigger recommended follow-on actions which might include conducting more precise standard measurements at a laboratory. Wear status, contamination status, and lubricant dielectric permittivity and viscosity status are derived quantitatively from multiple parameters measured.1.2 This practice is suitable for testing incoming and in-service lubricating oils in viscosity grades 32 mm2/s at 40 °C to 680 mm2/s at 40 °C having petroleum or synthetic base stock. This practice is intended to be used for testing in-service lubricant samples collected from pumps, electric motors, compressors, turbines, engines, transmissions, gearboxes, crushers, pulverizers, presses, hydraulics and similar machinery applications. This practice addresses operation and standardization to ensure repeatable results.1.3 This practice is not intended for use with crude oils.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.

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5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously. 5.2 Relative complex permittivity (relative complex dielectric constant), εr*, is the proportionality factor that relates the electric field to the electric flux density, and which depends on intrinsic material properties such as molecular polarizability, charge mobility, and so forth: where: ε0   =   the permittivity of free space, D→   =   the electric flux density vector, and E→   =   the electric field vector. Note 1: In common usage the word “relative” is frequently dropped. The real part of complex relative permittivity (εr′) is often referred to as simply relative permittivity, permittivity, or dielectric constant. The imaginary part of complex relative permittivity (εr′′) is often referred to as the loss factor. In anisotropic media, permittivity is described by a three dimensional tensor. Note 2: For the purposes of this test method, the media is considered to be isotropic and, therefore, permittivity is a single complex number at each frequency. 5.3 Relative complex permeability, μr*, is the proportionality factor that relates the magnetic flux density to the magnetic field, and which depends on intrinsic material properties such as magnetic moment, domain magnetization, and so forth: where: μ0   =   the permeability of free space, B→   =   the magnetic flux density vector, and H→   =   the magnetic field vector. Note 3: In common usage the word “relative” is frequently dropped. The real part of complex relative permeability (μr′) is often referred to as relative permeability or simply permeability. The imaginary part of complex relative permeability (μr″) is often referred to as the magnetic loss factor. In anisotropic media, permeability is described by a three dimensional tensor. Note 4: For the purposes of this test method, the media is considered to be isotropic, and therefore permeability is a single complex number at each frequency. 5.4 Relative permittivity ((relative dielectric constant) (SIC) κ′(εr)) is the real part of the relative complex permittivity. It is also the ratio of the equivalent parallel capacitance, Cp, of a given configuration of electrodes with a material as a dielectric to the capacitance, Cυ, of the same configuration of electrodes with vacuum (or air for most practical purposes) as the dielectric: Note 5: In common usage the word “relative” is frequently dropped. Note 6: Experimentally, vacuum must be replaced by the material at all points where it makes a significant change in capacitance. The equivalent circuit of the dielectric is assumed to consist of Cp, a capacitance in parallel with conductance. (See Fig. 3 of Test Methods D150.) Note 7: Cx is taken to be Cp, the equivalent parallel capacitance as shown in Fig. 3 of Test Methods D150. Note 8: The series capacitance is larger than the parallel capacitance by less than 1 % for a dissipation factor of 0.1, and by less than 0.1 % for a dissipation factor of 0.03. If a measuring circuit yields results in terms of series components, the parallel capacitance must be calculated from Eq 5 of Test Methods D150 before the corrections and permittivity are calculated. Note 9: The permittivity of dry air at 23 °C and standard pressure at 101.3 kPa is 1.000536. Its divergence from unity, κ′ − 1, is inversely proportional to absolute temperature and directly proportional to atmospheric pressure. The increase in permittivity when the space is saturated with water vapor at 23 °C is 0.00025, and varies approximately linearly with temperature expressed in degrees Celsius, from 10 °C to 27 °C. For partial saturation the increase is proportional to the relative humidity. 1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only. 1.2 This measurement method is valid over a frequency range of approximately 100 MHz to over 40 GHz. These limits are not exact and depend on the size of the specimen, the size of rectangular waveguide transmission line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. Use of multiple rectangular waveguide transmission line sizes are required to cover this entire frequency range (100 MHz to 40 GHz). This test method can also be generally applied to circular waveguide test fixtures. The rectangular waveguide fixture is preferred over coaxial fixtures when samples have in-plane anisotropy or are difficult to manufacture precisely. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are in inch-pound units and are included for information only. The equations shown here assume an e+jωt harmonic time convention. 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 The permeability determined by this method is the impedance permeability. Impedance permeability is the ratio of the peak value of flux density (Bmax) to the assumed peak magnetic field strength (Hz) without regard to phase. As compared to testing under sinusoidal flux (sinusoidal B) conditions, the permeabilities determined by this method are numerically lower since, for a given test signal frequency, the rate of flux change (dB/dt) is higher.4.2 This test method is suitable for impedance permeability measurements at very low magnetic inductions at power frequencies (50 Hz to 60 Hz) to moderate inductions below the point of maximum permeability of the material (the knee of the magnetization curve) or until there is visible distortion of the current waveform. The lower limit is a function of sample area, secondary turns, and the sensitivity of the flux-reading voltmeter used. At higher inductions, measurements of flux-generated voltages that are appreciably distorted mean that the flux has appreciable harmonic frequency components. The upper limit is given by the availability of pure sinusoidal current, which is a function of the power source. In addition, a large ratio (≥10) of the total series resistance of the primary circuit to the primary coil impedance is required. With proper test apparatus, this test method is suitable for use at frequencies up to 1 MHz.4.3 This test method is suitable for design, specification acceptance, service evaluation, quality control, and research use.1.1 This test method provides a means for determination of the impedance permeability (μz) of ferromagnetic materials under the condition of sinusoidal current (sinusoidal H) excitation. Test specimens in the form of laminated toroidal cores, tape-wound toroidal cores, and link-type laminated cores having uniform cross sections and closed flux paths (no air gaps) are used. The method is intended as a means for determining the magnetic performance of ferromagnetic strip having a thickness less than or equal to 0.025 in. [0.635 mm].1.2 This test method shall be used in conjunction with those applicable paragraphs in Practice A34/A34M.1.3 The values and equations stated in customary (cgs-emu and inch-pound) or SI units are to be regarded separately as standard. Within this standard, SI units are shown in brackets except for the sections concerning calculations where there are separate sections for the respective unit systems. The values stated 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 nonconformance with 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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