Continuous scan data collection

A total of 1463 raw intensity data were collected. Inspection of the azimuthal scan data showed a variation of /mia//max = 0.82 for the average curve. An empirical correction based on the observed variation was applied to the data as a first approximation. The structure was solved by Patterson methods in space group P. Refinement and elucidation of additional atoms proceeded via standard least-squares and Fourier techniques. Examination of the triclinic model demonstrated the correct monoclinic space group, P2Jc (the apparent absence of hOl, l 2n has been found), and refinement continued in (hat group... 

Figure 4.30. Powder diffraction pattern collected from an organo metallic compound on a Rigaku TTRAX powder diffractometer using Mo Ka radiation. The data were collected in a continuous scanning mode scan rate was 5 deg/min, sampling step 0.01°.

To account for the presumably statistical distribution of Ni and Sn atoms in the 2(c) and 3(g) sites in this crystal structure, the initial distribution of atoms in the unit cell has been assumed as listed in Table 7.2. The initial profile and structural parameters are found in the input file for LHPM-Rietica on the CD, the file name is Ch7Ex01a.inp. Experimental diffraction data, collected on a Rigaku TTRAX rotating anode powder diffractometer using Cu Ka radiation in a continuous scan mode, are located on the CD in the file Ch7Ex01 CuKa.dat. 

A Digilab 14B/D Fourier Transform infrared spectrometer was utilized to obtain l-cm 1 resolution spectra over the 4000-400 cm-1 region for polyether-urethane-urea films. The sample chamber was allowed to come to equilibrium with a continuous nitrogen purge prior to data collection of 1000 scans per sample. 

Data, collected by random experimental runs using probability and statistical models, may be a good way of approaching the responses of the system inside the experimental space scanned (19). Then, this would be a preliminary consideration when undertaking a model for a disperse phase/continuous matrix systems where the dispersed phase domains are rigid. 

An automated data collection system (DCS) of approximately 6(XX) channels continuously records the readings of the various sensors on an hourly basis. The DCS scans and records the readings of temperature, humidity, pressure, MPBXs, strain gages, convergence monitors, and current and voltage for heater power. The measurements made by the DCS are referred to as passive monitoring. Other measurements such as ERT, neutron logging, GPR, acoustic emissions, REKA probe, and others are made periodically (every few weeks to few... 

X-ray diffraction patterns were obtained with a Bruker D5005 Theta-Theta diffractometer equipped with a diffracted-beam graphite monochromator using Cu Ka radiation (1.54184 A). The data were collected by continuous scanning between 15 and 73° (20) with a counting time of 8 s per 0.02°. The recorded patterns were referred to the powder diffraction file PDF-2 Database (International Centre for Diffraction Data) for the identification of phases, using the software package DiffracPlus (Socabim-Bruker). 

The proton lineshape test uses chloroform in deuteroacetone typically at concentrations of 3% at or below 400 MHz, and 1% at or above 500 MHz. Older instruments and/ or probes of lower sensitivity or observations via outer decoupler coils may require 10% at 200 MHz and 3% at 500 MHz to prevent noise interfering with measurements close to the baseline. A single scan is collected and tbe data recorded under conditions of high digital resolution (acquisition time of 16 s ensuring the FID has decayed to zero) and processed without window functions. Do not be tempted to make measurements at the height of the satellites themselves unless these are confirmed by measurement to be 0.55%. Since these arise from protons bound to C, wbicb relax faster than those of tbe parent line, they may be relatively enhanced if full equilibrium is not established after previous pulses. The test result for a 400 MHz instrument is shown in Fig. 3.79. The traditional test for proton resolution, which dates back to the continuous-wave (CW) era (o-dichlorobenzene in deuteroacetone), is now no longer employed and has become part of NMR history. 

In step-scan mode, the moving mirror of the interferometer is stopped at each data acquisition point and held for some time (seconds to minutes) during which data are acquired. In step-scan mode the collected interferograms contain the same information as in continuous-scan mode, only the time required for the complete experiment is much longer. Under stroboscopic measuring conditions, a time resolution of 100 ns can be achieved. This technique can be applied to processes which can repeatedly be started under highly reproducible conditions. The step-scan technique can also be applied for the acquisition of voluminous data. This... 

Lephardt s original work was on the pyrolysis and combustion of tobacco, for which he used Ig samples. We have adapted the techniques to work with 5-lOmg samples of and have used it successfully to characterise a variety of polymers. Our standard conditions are IC C/min ramp rate, 50ml/min purge gas (usually N2), 10s data collection time (25 scans), continuous (GC mode). We use both identity and evolution profile of the evolved gases to evaluate the sample. 

However, for the same data collection time, interferometry is more sensitive to multiplicative noise (i.e., noise proportional to the signal) than continuous-scan interferometry [591]. To eliminate the multiplicative and 1// noise, phase modulation (at 400 Hz) of IR radiation in conjunction with LIA demodulation is used [591]. Since the LIA and some IR detectors need the IR signal to be modulated at a single carrier frequency, a mechanical chopper, phase modulation (when at each position the fixed mirror is dithered at a fixed frequency), or modulation of absorption of the sample is used to produce a carrier frequency. In this case, the TR measurement is referred to as a synchronous multiple-modulation experiment. Multiple modulation is unnecessary if the so-called dc coupled detector which does not require a varying signal is used. 

X-ray diffraction patterns were recorded using a Philips PW 1710 diffractometer with nickel-filtered CuKa radiation using both continuous and step-scan (over the range 25 <29< 35 in steps of 0.02" with data collected 10s each step) techniques. Data were analysed according to known procedures and relationships [22] with A1 powder used as standard to dehne instrumental line broadening. 

Overall, the stability principle applies to how stable the system appears not only before EIS collection, but also during a sweep. For more complicated systems, such as continuous flow cells, the flow rates must be kept constant during the scan to ensure a relatively constant concentration of electron donor and other media constituents. In general, every effort should be made to evaluate the experimental conditions and ensure that the system does not change prior to or during data collection. 

Much of the intrinsic difficulties with DSC measurements and the tedious data collecting process of traditional adiabatic calorimetry can be avoided by adiabatic scanning calorimetry. In this technique a measured heating power is continuously applied to (or extracted from) the sample and sample holder. It was used in the 1970s for the study of liquid-gas [17] and liquid-liquid critical points [18] and first applied to liquid crystals by us [19] and later also by Anisimov et al. [20]. In the dynamic modes the total heat capacity Cj is now given by ... 

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