Linear position sensitive detector

X-ray measurements were carried out with a small-angle diffractometer with a linear position-sensitive detector. Cu Ka radiation (X = 0.154 mn) was used (Mogilevski et al. 1984). The samples were rotated with respect to the incident beam, while the intensity was registered by linear position-sensitive detector. The angular resolution of the detector was 0.01°. The curves were acquired in the 20 range of 0.3-2.0°. X-ray reflection curves are presented in Figures 22 and 23 for wild-type and recombinant proteins, respectively. The... 

X-ray diffraction experiments were performed on a STOE STADI-P diffractometer (CuKai radiation X = 1.5406 A) equipped with a linear position-sensitive detector. The solutions and the solids were introduced in a 0.3mm capillary Lindemann tube (Debye-Sherrer geometry). 

Fig. 25. Schematic set-up for a small angle scattering experiment with a furnace incorporated into the beam line. The flux of the monochromatized beam is determined by an ionization chamber. A fraction of the primary beam is transmitted through a semitransparent beamstop and recorded together with the scattered photons with a linear position sensitive detector...

Fig. 31. Data aqmsition system used for research on polymers at DORIS. The start/stop signals emanating from a linear position sensitive detector is digitized by time-digital converter. The patterns are stored in a 64 kbyte memory. The time information is furnished by a time frame generator. The output of a thermocouple etc. is stored in the calibration channel unit. Data evaluation is possible by a PDF 11/24 computer. (C Constant Fraction Discriminator A Amplifier)...

Fig. 45. Small-angle x-ray scattering pattern of oriented polyethylene (LDPE Ltipolen 1840 D) during four temperature cycles as recorded by a linear position sensitive detector. The detector was oriented parallel to the meridian of the small angle pattern...

In multi-wire proportional chamber systems (MWPC-systems), and also in linear position sensitive detectors, the cathode electrodes are usually divided up into individual strips, from which the positional information can be extracted. 

The resistive chain, shown in Fig. 8, can be a resistive anode wire itself, for instance in a linear position sensitive detector, or it can consist of resistors connecting the cathode read-out pads. 

In principle, curved position sensitive detector can be replaced by a linear position sensitive detector covering segments 5 to 10° (20) wide. This approach considerably increases resolution and decreases Bragg peak widths, but the problem of the enhanced background remains. 

Reduction from the two-dimensional form to the one-dimensional equatorial form was a requirement of the equatorial diffractometer geometries utilizing point detectors or at most linear position sensitive detectors. Importantly, this correction is neither applicable to the Bragg-Brentano nor to the flat transmission geometry, but is only valid for the Debye-Scherrer geometry. 

The powder X-ray diffraction (XRD) patterns were obtained with Cu-Kai radiation on a STOE STADI-P diffractometer equipped with a curved germanium (111) primary monochromator and a linear position-sensitive detector. Typically, the diffractograms were collected at angles 20 between 1 and 10°. 

STO 01] STOWIK J., ZIEBA A., Geometrical equatorial aberrations in a Bragg-Brentano powder diffractometer with a linear position-sensitive detector , J. Appl. Cryst., vol. 34, p. 458-464, 2001. 

Diffraction patterns of these hydrated membranes were recorded with a linear position sensitive detector on a Kratky low-angle x-ray... 

A further increase in speed of data taking is expected by segmentation of detectors, i.e. each detector segment has its own read-out system. A linear position-sensitive detector develop recently at EMBL consists of 128 anode wires, with each of them acting as an individual counter. The integral count rate is 10 MHz of statistical events. A similar development has been started for area counters. The new diffractometer for X-ray resonance scattering in HASYLAB is equipped with three area counters (Fig. 5). This system can handle nearly a million statical events per second... 

Fig. 3. Assembly of microtubule protein monitored by time-resolved X-ray scattering. The projection plot shows an experiment using the EMBL instrument X33, camera length 3 m, linear position-sensitive detector with 256 channels, 256 time frames of 3 sec per run (not all shown), temperature jumps from 3 to 37 °C and back (arrows). Note the increase in central scatter during assembly and the change in side maxima. The side maximum of the cold solution is due to rings, that of the warm solution is due to microtubules. From [11]...

Fig. 14.16 X-ray diffraction patterns of a mixture of 0.6 LiFeP04 and 0.4 FeP04 recorded at 30 K steps from 298 to 633 K with magnification of 200 reflections. Bruker AXS D8 ADVANCE powdCT diffractomelCT was used with Co-Ka radiation and linear position-sensitive detector Vantec-1. Measurranent ranges were from 15° to 120°. The measurements were conducted under a high-purity He atmosphere in an Anton Paar HTK 450 temperature-controlled chamber...

Fig. 8 Experimental lay-out for the earliest version of combined WAXS/XRD experiments implemented at the SRS Daresbury using non-monochromatic radiation. The white beam is energy dispersed by using a bent Si monochromator. After passing the sample the dispersed beam (range 700 eV) was collected by a linear position sensitive detector. The position on the detector is related to the photon energy. Monochromatic radiation (bandwidth 30 eV) required for the XRD experiments was obtained by reducing the slit opening before the monochromator. (Reproduced by permission).

Evolution of silica within the organic matrix was followed by SAXS using a Kratky camera and a linear position-sensitive detector. The structure was described by the size of silica clusters and by fractal dimensions, Dm, characterizing compactness of the object. The fractal dimension was determined from the slope of the linear part of a double logarithmic SAXS plot of the scattered intensity I vs. scattering vector q (=(47T /X)sin 0), where 20 is the scattering angle. 

There is one domain, however, in which EWIF is probably unsurpassable. Due to the high sensitivity of fluorescence measurements, significant data can be obtained in much less than one minute. Therefore, the kinetics of formation of the adsorbed layer can be monitored almost in real time. Schemes in which the incident beam is kept fixed but where the detection is performed at various angles should further speed up the measurements especially if the single channel photomultiplier is replaced by a linear position sensitive detector. 

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