Standards ASTM frequency standard

ASTM 1986. Standard Methods Qf Test for Complex Permittivity (Dielectric Constant) of Solid Electrical Insulating Materials at Microwave Frequencies and Temperatures 1q 1650°C. Document D 2520-86 (Reapproved 1990). Philadelphia, PA. American Society for Testing and Materials (ASTM). 

Anon. 2003e. In Annual Book of ASTM Standards, D 6079 Standard Test Method for Evaluating Lubricity of Diesel Fuels by the High-Frequency Reciprocating Rig (HFRR) (vol. 05.03). West Conshohocken PA ASTM International. 

As described in more detail in Chapter 10, the American Society for Testing and Materials (ASTM) has established several compounds as frequency standards (13). The Raman shifts for these materials were determined by at least six independent laboratories, and the standard deviation of each frequency was less than 1 cm . Figure 5.7 shows a spectrum of 4-acetamidophenol, the active ingredient of Tylenol and several other analgesics. The indicated frequencies were determined with both 514.5- and 1064 nm lasers and did not show any laser wavelength dependence. 

Figure 5.7. Spectrum of 4-acetamidophenol obtained with a Spex 1403 double monochromator, photon counting PMT, and 514.5 nm laser. Frequencies are from ASTM Standard E 1840. Standard deviations of all frequencies except 213.3 and 3326.6 are less than 1 cm for determination by six independent laboratories.

Figure 10.14. Cyclohexane spectrum following correction with Kopp 2412 glass standard. Horizontal numbers are the peak areas (integrated over the shift range indicated by the horizontal bars), relative to the 801 cm peak area. Vertical numbers are the ASTM frequencies for cyclohexane listed in Table 10.4 and Reference 11. Intensity data is average of two spectrometers calibrated independently, as described in Reference 20. (See footnote e of Table 10.7.)...

The complex viscosity as a function of frequency, maximum strain and temperature is generally determined with one rheometer. Standard ASTM 4440-84/90 defines the measurement of rheological parameters of polymer samples using dynamic oscillation. This standard reiterates the importance of determining the linear viscoelastic region prior to performing dynamic frequency sweeps. 

USA Standards ASTM D671-93 Constant amplitude of force Two specimens of triangular form with rectangular cross-section Fixed frequency of 30 Hz... 

ASTM D150 Standard Test Methods for AC Loss Characteristics and Permittivity (Dielectric Constant) of Solid Electrical Insulation includes the determination of relative permittivity, dissipation factor, loss index, power factor, phase angle, and loss angle through specimens of solid electrical insulating materials when the standards used are lumped impedances. The frequency range that can be covered extends from less than 1 Hz to several hundred megahertz. 

Lindheim [90] pointed out that the ASTM G32 standard has some disadvantages. In particular it is difficult to relate certain important test parameters (i.e. frequency and amplitude) to real life values such as static pressure and flow velocity. Also, the bubble sizes are smaller and the pressure gradients differ from those in hydrodynamic cavitation. 

Dynamic techniques are used to determine storage and loss moduli, G and G respectively, and the loss tangent, tan 5. Some instmments are sensitive enough for the study of Hquids and can be used to measure the dynamic viscosity T 7 Measurements are made as a function of temperature, time, or frequency, and results can be used to determine transitions and chemical reactions as well as the properties noted above. Dynamic mechanical techniques for sohds can be grouped into three main areas free vibration, resonance-forced vibrations, and nonresonance-forced vibrations. Dynamic techniques have been described in detail (242,251,255,266,269—279). A number of instmments are Hsted in Table 8. Related ASTM standards are Hsted in Table 9. 

The British standards are the same as the IEC methods and numbered as BS EN 60243. The ASTM equivalent at power frequencies is D14936 which has a similar choice of procedures. The details of the procedures are left to the material specification and, again, it should be emphasised that results are only comparable if exactly the same procedure and conditions are used. There is also a separate ASTM method37 for proof testing of thin sheet material. ASTM D153 1 38 is for direct voltage and D342639 for impulse tests. 

ASTM D149, 97 (2004). Standard test method for dielectric breakdown voltage and dielectric strength of electrical insulating materials at commercial power frequencies. 

ASTM D2520, 2001. Standard test methods for complex permittivity (dielectric constant) of solid insulating materials at microwave frequencies to 1650°C. 

A very sensitive and accurate technique for the determination of low loss sample properties is called the perturbation technique. This measurement utilizes both the change in frequency and absorption characteristics of a tuned resonant cavity. Full theory and design details are available as a standardized procedure published by the American Society for Testing and Materials (ASTM 1986). 

There is also a standard test method for determination of major and minor elements in coal ash by inductively coupled plasma (ICP)-atomic emission spectrometry (ASTM D-6349). In the test method, the sample to be analyzed is ashed under standard conditions and ignited to constant weight. The ash is fused with a fluxing agent followed by dissolution of the melt in dilute acid solution. Alternatively, the ash is digested in a mixture of hydrofluoric, nitric, and hydrochloric acids. The solution is analyzed by (ICP)-atomic emission spectrometry for the elements. The basis of the method is the measurement of atomic emissions. Aqueous solutions of the samples are nebulized, and a portion of the aerosol that is produced is transported to the plasma torch, where excitation and emission occurs. Characteristic line emission spectra are produced by a radio-frequency inductively coupled plasma. A grating monochromator system is used to separate the emission lines, and the intensities of the lines are monitored by photomultiplier tube or photodiode array detection. The photocurrents from the detector... 

ASTM D-149. Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies. 

The ASTM standard for PR measurements stipulates that a scan rate of 6 V/h (0.167 mV/s) be used. For a 10 mV p-p scan, this corresponds to an equivalent frequency of 8 mHz. While there are many corrosion systems in which this is a low enough frequency to resolve Rp (+RQ), there are also many cases where it is not. In these cases, the estimates of the corrosion rate will be overestimates, as pointed out in the section on scan rate effects. 

The resonant beam test technique forms the basis of the ASTM Standard E756-83 for measuring the viscoelastic properties of damping materials. Fundamentally, the beam test requires that the resonant frequencies of a metal-beam, mounted in cantilever fashion, be determined as a function of temperature and frequency the beam is then coated with a polymer and the resonant frequencies and corresponding modal damping of the composite beam are determined as a function of temperature and frequency. From these two data sets, the vibration damping properties of the polymer can be evaluated. The ASTM Standard provides the necessary equations to obtain the complex modulus data from the collected test data and also provides guidelines for the proper choice of the specimens (1.21. The principal difference between the beam test and the other methods used here is that the beam test calculates the material properties from the test results on the metal beam and the composite beam whereas the... 

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