Development of a high resolution, high sensitivity cylindrical crystal spectrometer for line shape diagnostics of x-rays emitted from hot plasmas. Progress report, August 1, 1977--July 31, 1978

AbstractThe control of the concentration of Zn and its fluctuation in the high pressure Bridgman grown CdZnTe crystals is part of our characterization work on the ternary grown ingots grown in house. In order to reach both high sensitivity and high position resolution, we have developed a new system consisting of a X-ray generator, coupled to a focusing X-ray capillary, delivering intense beams in the micron scale, since the intensity gain is around a factor of 100 compared to conventional methods.The characteristic X-rays are measured through a high resolution CdZnTe detector (225 eV at 5.9 keV FWHM) cooled by a Peltier system. The results of our investigations on different kinds of crystals will be discussed.

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Abstract 898: Can Angiography With Synchrotron Radiation And A High Sensitivity Receiver Make Lower Doses Of Contrast Medium Possible?

Circulation ◽

10.1161/circ.118.suppl_18.s_627-c ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Taisuke Konishi ◽

Shonosuke Matsushita ◽

Kazuyuki Hyodo ◽

Haruhiko Sugimori ◽

Chiho Tokunaga ◽

...

Keyword(s):

High Resolution ◽

Synchrotron Radiation ◽

Contrast Medium ◽

High Sensitivity ◽

Photon Density ◽

X Rays ◽

Nih Image ◽

Beneficial Effects ◽

Image Capturing ◽

Angiographic Image

Introduction: Contrast-induced nephropathy (CIN) is a serious complication associated with angiography and interventional angioplasty. Increased doses of contrast medium are a major risk factor of CIN. It was assumed that the occurrence of CIN could be decreased by reducing the dose of contrast medium. We investigated the effects of a new high resolution and high contrast angiographic system on the application of diluted contrast medium. Method: Contrast medium was diluted to 32% (a stock solution), 24%, 16%, 12%, 8%, and 4%. Angiography of the hindlimb in rats using a synchrotron radiation and HARP receiver were performed with each concentration of contrast medium (n=5, respectively). The characteristics of synchrotron radiation are high photon density (10,000 times that of conventional X-rays) and straightness of the beam, which lead to high resolution (26 micrometer/pixel). A HARP Receiver is a high sensitivity image capturing system, which was developed by NHK Sci & Tech Res Lab (Tokyo, Japan). It is about 100 times more sensitive than conventional CCD cameras. Each angiographic image was evaluated by 256 grayscale intensity using graphic software NIH Image. The availability of each image as angiography was determined by the judgment of 5 independent cardiologists respectively. Results: In 256 grayscale, the minimum visible contrast distance for identifying vessels was 10. The value of each image in different concentrations of contrast medium was as follows: 4%: 14+/−12, 8%: 22+/−10, 12%: 23+/−18, 16%: 25+/−11, 24%: 28+/−11, 32%: 40+/−10. Vessels are identified from 4% to 32%. Availability as angiography was confirmed from 8% to 32% by common assent. Conclusions: The angiographic system using synchrotron radiation and a HARP receiver was able to take angiographic images with as low as 8% contrast medium. This may lead to beneficial effects in patients who cannot undergo sufficient angiography and interventional angioplasty due to renal dysfunction.

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High Resolution Spectroscopy of X-Rays from Antiprotonic Atoms Using a Low-Energy Crystal Spectrometer

Electromagnetic Cascade and Chemistry of Exotic Atoms ◽

10.1007/978-1-4899-3701-8_28 ◽

1990 ◽

pp. 295-300

Author(s):

G. L. Borchert ◽

D. Gotta ◽

O. W. B. Schult ◽

L. M. Simons ◽

K. Elsener ◽

...

Keyword(s):

High Resolution ◽

Low Energy ◽

High Resolution Spectroscopy ◽

X Rays ◽

Crystal Spectrometer ◽

Antiprotonic Atoms

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APPLICATION OF A CHARGE-DIVISION, POSITION-SENSITIVE PROPORTIONAL COUNTER TO HIGH-RESOLUTION PIXE MEASUREMENTS

International Journal of PIXE ◽

10.1142/s0129083590000116 ◽

1990 ◽

Vol 01 (02) ◽

pp. 141-146 ◽

Cited By ~ 4

Author(s):

HIROMI HAMANAKA ◽

KEN-ICHI HASEGAWA ◽

YASUHIRO YAMAMOTO

Keyword(s):

High Resolution ◽

Carbon Fiber ◽

Spatial Resolution ◽

Proportional Counter ◽

Simple Structure ◽

Correlation Factor ◽

X Rays ◽

Crystal Spectrometer ◽

Position Sensitive ◽

A Charge

A charge-division, position-sensitive proportional counter with a carbon-fiber anode and its associated signal processor has been developed. This counter is very small in volume with a simple structure and vacuum proof. The spatial resolution of 0.36 mm was achieved under a gas pressure of 1.7×105 Pa. A correlation factor between the position and the channel number was measured to be 0.97, indicating good linearity of the system. The detector was combined with a crystal spectrometer in order to measure spectra of particle-induced characteristic X rays. Energy resolutions measured at Si Kα (1.74 keV) and Fe Kα (6.4 keV) X rays are 4 and 34 eV, respectively.

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Sonography versus Plain x Rays in Diagnosis of Nasal Fractures

American Journal of Rhinology ◽

10.2500/ajr.2008.22.3239 ◽

2008 ◽

Vol 22 (6) ◽

pp. 613-616 ◽

Cited By ~ 19

Author(s):

Robert Giirkov ◽

Eike Krause ◽

Dirk Clevert

Keyword(s):

High Resolution ◽

Clinical Decision Making ◽

High Sensitivity ◽

Clinical Decision ◽

Diagnostic Value ◽

Lateral Nasal Wall ◽

X Rays ◽

Imaging Procedure ◽

High Resolution Ultrasonography ◽

Nasal Fractures

Background The standard imaging procedure for suspected nasal fractures has been radiography (XR). However, its usefulness for clinical decision making is highly controversial. High-resolution ultrasonography now offers a promising new diagnostic imaging option. In this study we compared the diagnostic value of high-resolution ultrasonography and conventional XR in the evaluation of suspected nasal fractures. Methods A prospective single-blinded study was performed. Ultrasound (US) and XR findings in 80 patients with suspected nasal fractures were compared with the definite clinical diagnosis with respect to sensitivity, specificity, and accuracy. Results For detection of fractures of the nasal dorsum, both modalities had high sensitivity (98 and 88% for US and XR, respectively) and specificity (95% for both US and XR). In lateral nasal wall fractures, specificity was higher for XR (75% versus 94%). Sensitivity was significantly higher for the US examination (98% versus 28%). In summary, the accuracy was higher for US. Conclusion When available, US should be the first-line imaging procedure in the evaluation of nasal fractures.

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