Step-size, measurements

The measurements were made along the cracks with an average step size of 3 mm. The predictions were calculated from a position -15 mm to + 15 ram for set 1, from -40 mm to + 40 mm for set 2 and from -25 mm to + 25 mm for set 3. The impedance change has been calculated at 1mm intervals in the range. Taking into account the symmetry of the configuration, only half of the predictions need to be calculated. 

Size reduction (qv) or comminution is the first and very important step in the processing of most minerals (2,6,10,20—24). It also involves large expenditures for heavy equipment, energy, operation, and maintenance. Size reduction is necessary because the value minerals are intimately associated with gangue and need to be Hberated, and/or because most minerals processing/separation methods require the ore mass to be of certain size and/or shape. Size reduction is also required in the case of quarry products to produce material of controlled particle size (see Size measurement of particles). In some instances, hberation of valuables or impurities from the ore matrix is achieved without any apparent size reduction. Scmbbers and attritors used in the industrial minerals plants, eg, phosphate, mtile, glass sands, or clay, ate examples. 

The Fe K-edge spectra were recorded in the transmission mode and a metallic iron foil spectrum was measured simultaneously with each sample spectrum for energy calibration. X-ray absorption spectra for each sample were collected from 7,520 to 8,470 eV, with a step size of 0.40 eV and acquisition times of ca. 68 s per sample. Measuring each sample, in turn, and repeating... 

If the most recent available measurements are at time step c, then a history horizon HAt can be defined from (tc — HAt) to tc, where At is the time step size. In order to obtain enough redundant information about the process, it is important to choose a horizon length appropriate to the dynamic of the specific system (Liebman et al., 1992). As shown in Fig. 5, only data measurements within the horizon will be reconciled during the nonlinear dynamic data reconciliation run. 

Dillingham, M. S., Wigley, D. B., and Webb, M. R. Demonstration of unidirectional single-stranded DNA translocation by PcrA helicase measurement of step size and translocation speed. Biochemistry 2000, 39, 205-12. 

Now the specimen is perfectly aligned and it remains to measure the rocking curve. This is normally done by selecting a step size on the axis and a counting time per step for the detector. Some systems will allow instead the selection of a total number of counts at each step, so that constant statistical accuracy is... 

Data for step-mobilities shown in Fig. 6 span an impressively large range a factor of 10 " separates step-mobilities measured by STM from the step-mobilities extracted from the relaxation of micron-sized gratings. Some discrepancies exist, but most of the step-mobilities are consistent with a single activation energy of 1.8 eV and an attempt rate given by the frequency of atomic vibrations. We hope that this initial comparison of step-mobility data will help motivate more detailed theoretical analysis and experiments on the coimections between step-mobility and the evolution of surface morphology. 

Crystal structure and phase distribution of the powders at room temperature were studied with an x-ray powder diffractometer (Bruker AXS-D8, Karlsruhe, Germany). The measurements were performed in the 20 range of 10-90°C at 40 kV and 40 mA, using Cu-Ka radiation. In all measurements, the step size was 0.03°C, and data collection period was 2 sec. in each step. Ka2 peaks are suppressed in the x-ray diffraction measurements. 

Step 1. Measure 1 to 4 L (or 25 mL, as specified by instructor) of water sample (which has been previously acidified) with a graduated cylinder and record the volume to the nearest 1 (or 0.1) mL. Filter the sample through a fluted filter paper and collect the filtrate in a clean beaker of appropriate size. 

In order to minimize external (bed) diffusion resistance and maximize the heat transfer rate it is desirable to use a very small adsorbent sample with the crystals spread as thinly as possible over the balance pan or within the containing vessel. To minimize the effect of non-linearities, such as the strong concentration dependence of the diffusivity, measurements should be made differentially over small concentration changes. Variation of the step size and comparison of adsorption and desorption curves provide simple tests for linearity of the system. The large differences between adsorption and desorption diffusivities, reported in some of the earlier work, have been shown to be due to the concentration dependence of the diffusivity(8) and in differential measurements under similar conditions no such anomaly was observed. 

Emission decays were obtained from a fs Tl sapphire laser uorescence upconversion spectrometer whose construction is reported elsewhere [8]. Here we only note that the overall temporal response used in these studies was between 112-125 fs as measured by the FWHM of the cross correlation between the pump and gate pulses. Decays (0-200 ps with a variable step size) were collected at a series of ten emission wavelengths (8 nm bandpass) which were then used to reconstruct time-evolving emission spectra in the manner described in Refs. 8 and 9. From these spectra the solvation dynamics was extracted in the form of the spectral response function,... 

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