WorldWideScience

Sample records for line-source based x-ray

  1. High intensity line source for x-ray spectrometer calibration

    International Nuclear Information System (INIS)

    Thoe, R.S.

    1986-06-01

    A high intensity electron-impact x-ray source using a one-dimensional Pierce lens has been built for the purpose of calibrating a bent crystal x-ray spectrometer. This source focuses up to 100 mA of 20-keV electrons to a line on a liquid-cooled anode. The line (which can serve as a virtual slit for the spectrometer) measures approximately 800 μ x 2 cm. The source is portable and therefore adaptable to numerous types of spectrometer applications. One particular application, the calibration of a high resolution (r = 10 4 ) time-resolved cyrstal spectrometer, will be discussed in detail

  2. Preferred orientation determination using line source x-ray diffraction

    International Nuclear Information System (INIS)

    Kimmel, G.; Shmarjahu, D.

    1977-10-01

    A texture goniometer has been attached to a diffractometer connected to a line-focus x-ray source. Reasonable results are obtained for the texture of rolled sheets and the test procedure is given. To illustrate the test procedure, the determination of preferred orientation in cold-rolled copper is described, as compared with random powder of sintered copper. Improvements of the measurements are proposed

  3. Method for spatially modulating X-ray pulses using MEMS-based X-ray optics

    Science.gov (United States)

    Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

    2015-03-10

    A method and apparatus are provided for spatially modulating X-rays or X-ray pulses using microelectromechanical systems (MEMS) based X-ray optics. A torsionally-oscillating MEMS micromirror and a method of leveraging the grazing-angle reflection property are provided to modulate X-ray pulses with a high-degree of controllability.

  4. Methods for calibrating the gain and offset of the DSSC detector for the European XFEL using X-ray line sources

    Science.gov (United States)

    Schlee, S.; Weidenspointner, G.; Moch, D.; Kuster, M.; Porro, M.

    2016-01-01

    The DSSC (DEPFET Sensor with Signal Compression) will be a silicon based, 2d 1 Mpx imaging detector for the European X-ray Free Electron Laser Facility (XFEL.EU) in Hamburg, Germany. The DSSC is foreseen for soft X-radiation from 0.5 keV up to 6 keV . Driven by its scientific requirements, the design goals of the detector system are single photon detection, high dynamic range and a high frame rate of up to 4.5 MHz. Signal compression and amplification will be performed in the silicon sensor pixels yielding a low signal noise. Utilizing an in-pixel active filtering stage and an 8/9-bit ADC, the detector will provide parallel read-out of all pixels. In order to calibrate offset and gain, the procedure currently under investigation relies on determining peak positions in measurements with calibration line sources such as 55Fe. Here the status of studies of the stability and performance of a parameterized fit function designed for this task will be presented.

  5. CCD-based X-ray detectors for X-ray diffraction studies

    International Nuclear Information System (INIS)

    Ito, K.; Amemiya, Y.

    1999-01-01

    CCD-based X-ray detectors are getting to be used for X-ray diffraction studies especially in the studies where real time (automated) measurements and time-resolved measurements are required. Principles and designs of two typical types of CCD-based detectors are described; one is ths system in which x-ray image intensifiers are coupled to maximize the detective quantum efficiency for time-resolved measurements, and the other is the system in which tapered optical fibers are coupled for the reduction of the image into the CCD, which is optimized for automated measurements for protein crystallography. These CCD-based X-ray detectors have an image distortion and non-uniformity of response to be corrected by software. Correction schemes which we have developed are also described. (author)

  6. Cone-beam x-ray luminescence computed tomography based on x-ray absorption dosage

    Science.gov (United States)

    Liu, Tianshuai; Rong, Junyan; Gao, Peng; Zhang, Wenli; Liu, Wenlei; Zhang, Yuanke; Lu, Hongbing

    2018-02-01

    With the advances of x-ray excitable nanophosphors, x-ray luminescence computed tomography (XLCT) has become a promising hybrid imaging modality. In particular, a cone-beam XLCT (CB-XLCT) system has demonstrated its potential in in vivo imaging with the advantage of fast imaging speed over other XLCT systems. Currently, the imaging models of most XLCT systems assume that nanophosphors emit light based on the intensity distribution of x-ray within the object, not completely reflecting the nature of the x-ray excitation process. To improve the imaging quality of CB-XLCT, an imaging model that adopts an excitation model of nanophosphors based on x-ray absorption dosage is proposed in this study. To solve the ill-posed inverse problem, a reconstruction algorithm that combines the adaptive Tikhonov regularization method with the imaging model is implemented for CB-XLCT reconstruction. Numerical simulations and phantom experiments indicate that compared with the traditional forward model based on x-ray intensity, the proposed dose-based model could improve the image quality of CB-XLCT significantly in terms of target shape, localization accuracy, and image contrast. In addition, the proposed model behaves better in distinguishing closer targets, demonstrating its advantage in improving spatial resolution.

  7. Nanomaterial-based x-ray sources

    Science.gov (United States)

    Cole, Matthew T.; Parmee, R. J.; Milne, William I.

    2016-02-01

    Following the recent global excitement and investment in the emerging, and rapidly growing, classes of one and two-dimensional nanomaterials, we here present a perspective on one of the viable applications of such materials: field electron emission based x-ray sources. These devices, which have a notable history in medicine, security, industry and research, to date have almost exclusively incorporated thermionic electron sources. Since the middle of the last century, field emission based cathodes were demonstrated, but it is only recently that they have become practicable. We outline some of the technological achievements of the past two decades, and describe a number of the seminal contributions. We explore the foremost market hurdles hindering their roll-out and broader industrial adoption and summarise the recent progress in miniaturised, pulsed and multi-source devices.

  8. Kharkov X-ray Generator Based On Compton Scattering

    International Nuclear Information System (INIS)

    Shcherbakov, A.; Zelinsky, A.; Mytsykov, A.; Gladkikh, P.; Karnaukhov, I.; Lapshin, V.; Telegin, Y.; Androsov, V.; Bulyak, E.; Botman, J.I.M.; Tatchyn, R.; Lebedev, A.

    2004-01-01

    Nowadays X-ray sources based on storage rings with low beam energy and Compton scattering of intense laser beams are under development in several laboratories. An international cooperative project of an advanced X-ray source of this type at the Kharkov Institute of Physics and Technology (KIPT) is described. The status of the project is reviewed. The design lattice of the storage ring and calculated X-ray beam parameters are presented. The results of numerical simulation carried out for proposed facility show a peak spectral X-ray intensity of about 1014 can be produced

  9. Novel X-ray Communication Based XNAV Augmentation Method Using X-ray Detectors

    Directory of Open Access Journals (Sweden)

    Shibin Song

    2015-09-01

    Full Text Available The further development of X-ray pulsar-based NAVigation (XNAV is hindered by its lack of accuracy, so accuracy improvement has become a critical issue for XNAV. In this paper, an XNAV augmentation method which utilizes both pulsar observation and X-ray ranging observation for navigation filtering is proposed to deal with this issue. As a newly emerged concept, X-ray communication (XCOM shows great potential in space exploration. X-ray ranging, derived from XCOM, could achieve high accuracy in range measurement, which could provide accurate information for XNAV. For the proposed method, the measurement models of pulsar observation and range measurement observation are established, and a Kalman filtering algorithm based on the observations and orbit dynamics is proposed to estimate the position and velocity of a spacecraft. A performance comparison of the proposed method with the traditional pulsar observation method is conducted by numerical experiments. Besides, the parameters that influence the performance of the proposed method, such as the pulsar observation time, the SNR of the ranging signal, etc., are analyzed and evaluated by numerical experiments.

  10. X-ray generator based on Compton scattering

    NARCIS (Netherlands)

    Androsov, V.P.; Agafonov, A.V.; Botman, J.I.M.; Bulyak, E.V.; Drebot, I.; Gladkikh, P.I.; Grevtsev, V.; Ivashchenko, V.; Karnaukhov, I.M.; Lapshin, V.I.

    2005-01-01

    Nowadays, the sources of the X-rays based on a storage ring with low beam energy and Compton scattering of intense laser beam are under development in several laboratories. In the paper the state-of-art in development and construction of cooperative project of a Kharkov advanced X-ray source NESTOR

  11. A laboratory-based hard x-ray monochromator for high-resolution x-ray emission spectroscopy and x-ray absorption near edge structure measurements

    Energy Technology Data Exchange (ETDEWEB)

    Seidler, G. T., E-mail: seidler@uw.edu; Mortensen, D. R.; Remesnik, A. J.; Pacold, J. I.; Ball, N. A.; Barry, N.; Styczinski, M.; Hoidn, O. R. [Physics Department, University of Washington, Seattle, Washington 98195-1560 (United States)

    2014-11-15

    We report the development of a laboratory-based Rowland-circle monochromator that incorporates a low power x-ray (bremsstrahlung) tube source, a spherically bent crystal analyzer, and an energy-resolving solid-state detector. This relatively inexpensive, introductory level instrument achieves 1-eV energy resolution for photon energies of ∼5 keV to ∼10 keV while also demonstrating a net efficiency previously seen only in laboratory monochromators having much coarser energy resolution. Despite the use of only a compact, air-cooled 10 W x-ray tube, we find count rates for nonresonant x-ray emission spectroscopy comparable to those achieved at monochromatized spectroscopy beamlines at synchrotron light sources. For x-ray absorption near edge structure, the monochromatized flux is small (due to the use of a low-powered x-ray generator) but still useful for routine transmission-mode studies of concentrated samples. These results indicate that upgrading to a standard commercial high-power line-focused x-ray tube or rotating anode x-ray generator would result in monochromatized fluxes of order 10{sup 6}–10{sup 7} photons/s with no loss in energy resolution. This work establishes core technical capabilities for a rejuvenation of laboratory-based hard x-ray spectroscopies that could have special relevance for contemporary research on catalytic or electrical energy storage systems using transition-metal, lanthanide, or noble-metal active species.

  12. Sources of the X-rays Based on Compton Scattering

    International Nuclear Information System (INIS)

    Androsov, V.; Bulyak, E.; Gladkikh, P.; Karnaukhov, I.; Mytsykov, A.; Telegin, Yu.; Shcherbakov, A.; Zelinsky, A.

    2007-01-01

    The principles of the intense X-rays generation by laser beam scattering on a relativistic electron beam are described and description of facilities assigned to produce the X-rays based on Compton scattering is presented. The possibilities of various types of such facilities are estimated and discussed. The source of the X-rays based on a storage ring with low beam energy is described in details and advantages of the sources of such type are discussed.The results of calculation and numerical simulation carried out for laser electron storage ring NESTOR that is under development in NSC KIPT show wide prospects of the accelerator facility of such type

  13. Development of X-ray detector based on phototransistor

    International Nuclear Information System (INIS)

    Ramacos Fardela; Kusminarto

    2014-01-01

    X-ray interaction with matter can produce phenomenon of fluorescence that emits visible light. This phenomenon has been exploited to design an X-ray detector based on photo transistor by attaching a screen ZnS(Ag) on the surface of the photo transistor which is arranged in a Darlington circuit. Response of detector was done by collimating of X-rays beam from the X-ray generator tube Philips 2000 watts, 60 kV type PW 2215/20 NR 780 026 and measure the detector output voltage (V out ). Varying the current by 5, 10, 15, 20, 25, 30, 35 and 40 mA in the X-ray panel. The experimental results showed that the Darlington circuit can be applied to design the detector of X-ray based on phototransistor. The results show that there is a linear relationship between the change in the intensity of X-ray detectors with voltage output phototransistor when it was closed with fluorescence materials ZnS(Ag), the linearity coefficient was R 2 = 0.99. Sensitivity of detector was obtained to be 3.7 x 10 -2 mV per cpm. (author)

  14. X-ray detectors based on image sensors

    International Nuclear Information System (INIS)

    Costa, A.P.R.

    1983-01-01

    X-ray detectors based on image sensors are described and a comparison is made between the advantages and the disadvantages of such a kind of detectors with the position sensitive detectors. (L.C.) [pt

  15. Spherical grating based x-ray Talbot interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Cong, Wenxiang, E-mail: congw@rpi.edu, E-mail: xiy2@rpi.edu, E-mail: wangg6@rpi.edu; Xi, Yan, E-mail: congw@rpi.edu, E-mail: xiy2@rpi.edu, E-mail: wangg6@rpi.edu; Wang, Ge, E-mail: congw@rpi.edu, E-mail: xiy2@rpi.edu, E-mail: wangg6@rpi.edu [Biomedical Imaging Center, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2015-11-15

    Purpose: Grating interferometry is a state-of-the-art x-ray imaging approach, which can acquire information on x-ray attenuation, phase shift, and small-angle scattering simultaneously. Phase-contrast imaging and dark-field imaging are very sensitive to microstructural variation and offers superior contrast resolution for biological soft tissues. However, a common x-ray tube is a point-like source. As a result, the popular planar grating imaging configuration seriously restricts the flux of photons and decreases the visibility of signals, yielding a limited field of view. The purpose of this study is to extend the planar x-ray grating imaging theory and methods to a spherical grating scheme for a wider range of preclinical and clinical applications. Methods: A spherical grating matches the wave front of a point x-ray source very well, allowing the perpendicular incidence of x-rays on the grating to achieve a higher visibility over a larger field of view than the planer grating counterpart. A theoretical analysis of the Talbot effect for spherical grating imaging is proposed to establish a basic foundation for x-ray spherical gratings interferometry. An efficient method of spherical grating imaging is also presented to extract attenuation, differential phase, and dark-field images in the x-ray spherical grating interferometer. Results: Talbot self-imaging with spherical gratings is analyzed based on the Rayleigh–Sommerfeld diffraction formula, featuring a periodic angular distribution in a polar coordinate system. The Talbot distance is derived to reveal the Talbot self-imaging pattern. Numerical simulation results show the self-imaging phenomenon of a spherical grating interferometer, which is in agreement with the theoretical prediction. Conclusions: X-ray Talbot interferometry with spherical gratings has a significant practical promise. Relative to planar grating imaging, spherical grating based x-ray Talbot interferometry has a larger field of view and

  16. Spherical grating based x-ray Talbot interferometry

    International Nuclear Information System (INIS)

    Cong, Wenxiang; Xi, Yan; Wang, Ge

    2015-01-01

    Purpose: Grating interferometry is a state-of-the-art x-ray imaging approach, which can acquire information on x-ray attenuation, phase shift, and small-angle scattering simultaneously. Phase-contrast imaging and dark-field imaging are very sensitive to microstructural variation and offers superior contrast resolution for biological soft tissues. However, a common x-ray tube is a point-like source. As a result, the popular planar grating imaging configuration seriously restricts the flux of photons and decreases the visibility of signals, yielding a limited field of view. The purpose of this study is to extend the planar x-ray grating imaging theory and methods to a spherical grating scheme for a wider range of preclinical and clinical applications. Methods: A spherical grating matches the wave front of a point x-ray source very well, allowing the perpendicular incidence of x-rays on the grating to achieve a higher visibility over a larger field of view than the planer grating counterpart. A theoretical analysis of the Talbot effect for spherical grating imaging is proposed to establish a basic foundation for x-ray spherical gratings interferometry. An efficient method of spherical grating imaging is also presented to extract attenuation, differential phase, and dark-field images in the x-ray spherical grating interferometer. Results: Talbot self-imaging with spherical gratings is analyzed based on the Rayleigh–Sommerfeld diffraction formula, featuring a periodic angular distribution in a polar coordinate system. The Talbot distance is derived to reveal the Talbot self-imaging pattern. Numerical simulation results show the self-imaging phenomenon of a spherical grating interferometer, which is in agreement with the theoretical prediction. Conclusions: X-ray Talbot interferometry with spherical gratings has a significant practical promise. Relative to planar grating imaging, spherical grating based x-ray Talbot interferometry has a larger field of view and

  17. Unitary bases for x-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Patterson, C.W.; Harter, W.G.; Schneider, W.D.

    1979-01-01

    A Gelfand basis is used to derive the coefficients of fractional parentage (CFP's) used to calculate intensities for x-ray photoelectron spectroscopy of atoms. Using associated Gelfand bases, we show that it is easy to derive the Racah CFP relations between particles and holes

  18. A bromine-based dichroic X-ray polarization analyser

    CERN Document Server

    Collins, S P; Brown, S D; Thompson, P

    2001-01-01

    We have demonstrated the advantages offered by dichroic X-ray polarization filters for linear polarization analysis, and describe such a device, based on a dibromoalkane/urea inclusion compound. The polarizer has been successfully tested by analysing the polarization of magnetic diffraction from holmium.

  19. Analyser-based x-ray imaging for biomedical research

    International Nuclear Information System (INIS)

    Suortti, Pekka; Keyriläinen, Jani; Thomlinson, William

    2013-01-01

    Analyser-based imaging (ABI) is one of the several phase-contrast x-ray imaging techniques being pursued at synchrotron radiation facilities. With advancements in compact source technology, there is a possibility that ABI will become a clinical imaging modality. This paper presents the history of ABI as it has developed from its laboratory source to synchrotron imaging. The fundamental physics of phase-contrast imaging is presented both in a general sense and specifically for ABI. The technology is dependent on the use of perfect crystal monochromator optics. The theory of the x-ray optics is developed and presented in a way that will allow optimization of the imaging for specific biomedical systems. The advancement of analytical algorithms to produce separate images of the sample absorption, refraction angle map and small-angle x-ray scattering is detailed. Several detailed applications to biomedical imaging are presented to illustrate the broad range of systems and body sites studied preclinically to date: breast, cartilage and bone, soft tissue and organs. Ultimately, the application of ABI in clinical imaging will depend partly on the availability of compact sources with sufficient x-ray intensity comparable with that of the current synchrotron environment. (paper)

  20. An Intraoral Miniature X-ray Tube Based on Carbon Nanotubes for Dental Radiography

    OpenAIRE

    Hyun Jin Kim; Hyun Nam Kim; Hamid Saeed Raza; Han Beom Park; Sung Oh Cho

    2016-01-01

    A miniature X-ray tube based on a carbon-nanotube electron emitter has been employed for the application to a dental radiography. The miniature X-ray tube has an outer diameter of 7 mm and a length of 47 mm. The miniature X-ray tube is operated in a negative high-voltage mode in which the X-ray target is electrically grounded. In addition, X-rays are generated only to the teeth directions using a collimator while X-rays generated to other directions are shielded. Hence, the X-ray tube can be ...

  1. Performances for confocal X-ray diffraction technology based on polycapillary slightly focusing X-ray optics

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hehe; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stxbeijing@163.com [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Peng, Song [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Sun, Weiyuan; Li, Yude; Lin, Xiaoyan; Zhao, Weigang; Zhao, Guangcui; Luo, Ping; Pan, Qiuli; Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2013-09-21

    The confocal X-ray diffraction (XRD) technology based on a polycapillary slightly focusing X-ray lens (PSFXRL) in excitation channel and a polycapillary parallel X-ray lens (PPXRL) with a long input focal distance in detection channel was developed. The output focal spot of the PSFXRL and the input focal spot of the PPXRL were adjusted in confocal configuration, and only the X-rays from the volume overlapped by these foci could be accordingly detected. This confocal configuration was helpful in decreasing background. The convergence of the beam focused by the PSFXRL and divergence of the beam which could be collected by the PPXRL with a long input focal distance were both about 9 mrad at 8 keV. This was helpful in improving the resolution of lattice spacing of this confocal XRD technology. The gain in power density of such PSFXRL and PPXRL was about 120 and 7 at 11 keV, respectively, which was helpful in using the low power source to perform XRD analysis efficiently. The performances of this confocal XRD technology were provided, and some common plastics were analyzed. The experimental results demonstrated that the confocal diffraction technology base on polycapillary slightly focusing X-ray optics had wide potential applications.

  2. Building lab-scale x-ray tube based irradiators

    International Nuclear Information System (INIS)

    Haff, Ron; Jackson, Eric; Gomez, Joseph; Light, Doug; Follett, Peter; Simmons, Greg; Higbee, Brad

    2016-01-01

    Here we report the use of x-ray tube based irradiators as alternatives to gamma sources for laboratory scale irradiation. Irradiators were designed with sample placement in closest possible proximity to the source, allowing high dose rates for small samples. Designs using 1000 W x-ray tubes in single tube, double tube, and four tube configurations are described, as well as various cabinet construction techniques. Relatively high dose rates were achieved for small samples, demonstrating feasibility for laboratory based irradiators for research purposes. Dose rates of 9.76, 5.45, and 1.7 Gy/min/tube were measured at the center of a 12.7 cm container of instant rice at 100 keV, 70 keV, and 40 keV, respectively. Dose uniformity varies dramatically as the distance from source to container. For 2.54 cm diameter sample containers containing adult Navel Orangeworm, dose rates of 50–60 Gy/min were measured in the four tube system. - Highlights: • X-ray is demonstrated as an alternative to gamma for lab-based irradiation. • Cabinets using one, two, and four 1000 W tubes are reported. • Dose rate of 9.8 Gy/min/tube at the center of a 12.7 cm container of instant rice. • Dose uniformity varies dramatically as the distance from source to container.

  3. Compact X-ray source based on Compton backscattering

    CERN Document Server

    Bulyak, E V; Zelinsky, A; Karnaukhov, I; Kononenko, S; Lapshin, V G; Mytsykov, A; Telegin, Yu P; Khodyachikh, A; Shcherbakov, A; Molodkin, V; Nemoshkalenko, V; Shpak, A

    2002-01-01

    The feasibility study of an intense X-ray source based on the interaction between the electron beam in a compact storage ring and the laser pulse accumulated in an optical resonator is carried out. We propose to reconstruct the 160 MeV electron storage ring N-100, which was shutdown several years ago. A new magnetic lattice will provide a transverse of electron beam size of approx 35 mu m at the point of electron beam-laser beam interaction. The proposed facility is to generate X-ray beams of intensity approx 2.6x10 sup 1 sup 4 s sup - sup 1 and spectral brightness approx 10 sup 1 sup 2 phot/0.1%bw/s/mm sup 2 /mrad sup 2 in the energy range from 10 keV up to 0.5 MeV. These X-ray beam parameters meet the requirements for most of technological and scientific applications. Besides, we plan to use the new facility for studying the laser cooling effect.

  4. Compact X-ray source based on Compton backscattering

    Energy Technology Data Exchange (ETDEWEB)

    Bulyak, E.; Gladkikh, P.; Zelinsky, A. E-mail: zelinsky@kipt.kharkov.ua; Karnaukhov, I.; Kononenko, S.; Lapshin, V.; Mytsykov, A.; Telegin, Yu.; Khodyachikh, A.; Shcherbakov, A.; Molodkin, V.; Nemoshkalenko, V.; Shpak, A

    2002-07-21

    The feasibility study of an intense X-ray source based on the interaction between the electron beam in a compact storage ring and the laser pulse accumulated in an optical resonator is carried out. We propose to reconstruct the 160 MeV electron storage ring N-100, which was shutdown several years ago. A new magnetic lattice will provide a transverse of electron beam size of {approx}35 {mu}m at the point of electron beam-laser beam interaction. The proposed facility is to generate X-ray beams of intensity {approx}2.6x10{sup 14} s{sup -1} and spectral brightness {approx}10{sup 12} phot/0.1%bw/s/mm{sup 2}/mrad{sup 2} in the energy range from 10 keV up to 0.5 MeV. These X-ray beam parameters meet the requirements for most of technological and scientific applications. Besides, we plan to use the new facility for studying the laser cooling effect.

  5. Simulation and application of micro X-ray fluorescence based on an ellipsoidal capillary

    Science.gov (United States)

    Yang, Jing; Li, Yude; Wang, Xingyi; Zhang, Xiaoyun; Lin, Xiaoyan

    2017-06-01

    A micro X-ray fluorescence setup was presented, based on an ellipsoidal capillary and a traditional laboratorial X-ray source. Using Ray-tracing principle, we have simulated the transmission path of X-ray beam in the ellipsoidal capillary and designed the optimal parameters of the ellipsoidal capillary for the micro X-ray fluorescence setup. We demonstrate that ellipsoidal capillary is well suited as condenser for the micro X-ray fluorescence based on traditional laboratorial X-ray source. Furthermore, we obtain the 2D mapping image of the leaf blade sample by using the ellipsoidal capillary we designed.

  6. A mirror for lab-based quasi-monochromatic parallel x-rays.

    Science.gov (United States)

    Nguyen, Thanhhai; Lu, Xun; Lee, Chang Jun; Jung, Jin-Ho; Jin, Gye-Hwan; Kim, Sung Youb; Jeon, Insu

    2014-09-01

    A multilayered parabolic mirror with six W/Al bilayers was designed and fabricated to generate monochromatic parallel x-rays using a lab-based x-ray source. Using this mirror, curved bright bands were obtained in x-ray images as reflected x-rays. The parallelism of the reflected x-rays was investigated using the shape of the bands. The intensity and monochromatic characteristics of the reflected x-rays were evaluated through measurements of the x-ray spectra in the band. High intensity, nearly monochromatic, and parallel x-rays, which can be used for high resolution x-ray microscopes and local radiation therapy systems, were obtained.

  7. Combined optic system based on polycapillary X-ray optics and single-bounce monocapillary optics for focusing X-rays from a conventional laboratory X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xuepeng; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stx@bnu.edu.cn [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Yi, Longtao; Sun, Weiyuan; Li, Fangzuo; Jiang, Bowen [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2015-12-01

    Two combined optic systems based on polycapillary X-ray optics and single-bounce monocapillary optics (SBMO) were designed for focusing the X-rays from a conventional laboratory X-ray source. One was based on a polycapillary focusing X-ray lens (PFXRL) and a single-bounce ellipsoidal capillary (SBEC), in which the output focal spot with the size of tens of micrometers of the PFXRL was used as the “virtual” X-ray source for the SBEC. The other system was based on a polycapillary parallel X-ray lens (PPXRL) and a single-bounce parabolic capillary (SBPC), in which the PPXRL transformed the divergent X-ray beam from an X-ray source into a quasi-parallel X-ray beam with the divergence of sever milliradians as the incident illumination of the SBPC. The experiment results showed that the combined optic systems based on PFXRL and SBEC with a Mo rotating anode X-ray generator with the focal spot with a diameter of 300 μm could obtain a focal spot with the total gain of 14,300 and focal spot size of 37.4 μm, and the combined optic systems based on PPXRL and SBPC with the same X-ray source mentioned above could acquire a focal spot with the total gain of 580 and focal spot size of 58.3 μm, respectively. The two combined optic systems have potential applications in micro X-ray diffraction, micro X-ray fluorescence, micro X-ray absorption near edge structure, full field X-ray microscopes and so on.

  8. A compact X-ray source based on Compton scattering

    Energy Technology Data Exchange (ETDEWEB)

    Bulyak, E.; Gladkikh, P.; Grigor' ev, Yu.; Guk, I.; Karnaukhov, I.; Khodyachikh, A.; Kononenko, S.; Mocheshnikov, N.; Mytsykov, A.; Shcherbakov, A. E-mail: shcherbakov@kipt.kharkov.ua; Tarasenko, A.; Telegin, Yu.; Zelinsky, A

    2001-07-21

    The main parameters of Kharkov electron storage ring N-100 with a beam energy range from 70 to 150 MeV are presented. The main results that were obtained in experimental researches are briefly described. The future of the N-100 upgrade to the development of the X-ray generator based on Compton back-scattering are presented. The electron beam energy range will be extended up to 250 MeV and the circumference of the storage ring will be 13.72 m. The lattice, parameters of the electron beam and the Compton back-scattering photons flux are described.

  9. A compact X-ray source based on Compton scattering

    International Nuclear Information System (INIS)

    Bulyak, E.; Gladkikh, P.; Grigor'ev, Yu.; Guk, I.; Karnaukhov, I.; Khodyachikh, A.; Kononenko, S.; Mocheshnikov, N.; Mytsykov, A.; Shcherbakov, A.; Tarasenko, A.; Telegin, Yu.; Zelinsky, A.

    2001-01-01

    The main parameters of Kharkov electron storage ring N-100 with a beam energy range from 70 to 150 MeV are presented. The main results that were obtained in experimental researches are briefly described. The future of the N-100 upgrade to the development of the X-ray generator based on Compton back-scattering are presented. The electron beam energy range will be extended up to 250 MeV and the circumference of the storage ring will be 13.72 m. The lattice, parameters of the electron beam and the Compton back-scattering photons flux are described

  10. A miniature X-ray tube based on carbon nanotube for an intraoral dental radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Jin; Park, Han Beom; Lee, Ju Hyuk; Cho, Sung Oh [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    The number of human teeth that can be radiographically taken is limited. Moreover, at least two X-ray shots are required to get images of teeth from both sides of the mouth. In order to overcome the disadvantages of conventional dental radiography, a dental radiograph has been proposed in which an X-ray tube is inserted into the mouth while an X-ray detector is placed outside the mouth. The miniature X-ray tube is required small size to insert into the mouth. Recently, we have fabricated a miniature x-ray tube with the diameter of 7 mm using a carbon nanotube (CNT) field. But, commercialized miniature X-ray tube were adopted a thermionic type using tungsten filament. The X-ray tubes adopted thermionic emission has a disadvantage of increasing temperature of x-ray tube. So it need to cooling system to cool x-ray tube. On the other hands, X-ray tubes adopted CNT field emitters don't need cooling systems because electrons are emitted from CNT by applying high voltage without heating. We have developed the miniature x-ray tube that produce x-ray with uniform spatial distribution based on carbon nanotube field emitters. The fabricated miniature x-ray tube can be stably and reliably operated at 50kV without any vacuum pump. The developed miniature X-ray tube was applied for intraoral dental radiography that employs an intra-oral CNT-based miniature X-ray tube and extra-oral X-ray detectors. An X-ray image of many teeth was successfully obtained by a single X-ray shot using the intra-oral miniature X-ray tube system. Furthermore, images of both molar teeth of pig were simultaneously obtained by a single X-ray shot. These results show that the intraoral dental radiography, which employs an intraoral miniature X-ray tube and an extraoral X-ray detector, performs better than conventional dental radiography.

  11. A miniature X-ray tube based on carbon nanotube for an intraoral dental radiography

    International Nuclear Information System (INIS)

    Kim, Hyun Jin; Park, Han Beom; Lee, Ju Hyuk; Cho, Sung Oh

    2016-01-01

    The number of human teeth that can be radiographically taken is limited. Moreover, at least two X-ray shots are required to get images of teeth from both sides of the mouth. In order to overcome the disadvantages of conventional dental radiography, a dental radiograph has been proposed in which an X-ray tube is inserted into the mouth while an X-ray detector is placed outside the mouth. The miniature X-ray tube is required small size to insert into the mouth. Recently, we have fabricated a miniature x-ray tube with the diameter of 7 mm using a carbon nanotube (CNT) field. But, commercialized miniature X-ray tube were adopted a thermionic type using tungsten filament. The X-ray tubes adopted thermionic emission has a disadvantage of increasing temperature of x-ray tube. So it need to cooling system to cool x-ray tube. On the other hands, X-ray tubes adopted CNT field emitters don't need cooling systems because electrons are emitted from CNT by applying high voltage without heating. We have developed the miniature x-ray tube that produce x-ray with uniform spatial distribution based on carbon nanotube field emitters. The fabricated miniature x-ray tube can be stably and reliably operated at 50kV without any vacuum pump. The developed miniature X-ray tube was applied for intraoral dental radiography that employs an intra-oral CNT-based miniature X-ray tube and extra-oral X-ray detectors. An X-ray image of many teeth was successfully obtained by a single X-ray shot using the intra-oral miniature X-ray tube system. Furthermore, images of both molar teeth of pig were simultaneously obtained by a single X-ray shot. These results show that the intraoral dental radiography, which employs an intraoral miniature X-ray tube and an extraoral X-ray detector, performs better than conventional dental radiography

  12. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    International Nuclear Information System (INIS)

    Nicoul, Matthieu

    2010-01-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0±0.3) ps, and the ratio of the Grueneisen parameters was found to be γ e / γ i = (0.5±0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A 1g mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase and its development for excitations close to the

  13. Time-resolved X-ray diffraction with accelerator- and laser-plasma-based X-ray sources

    Energy Technology Data Exchange (ETDEWEB)

    Nicoul, Matthieu

    2010-09-01

    Femtosecond X-ray pulses are a powerful tool to investigate atomic motions triggered by femtosecond pump pulses. This thesis is dedicated to the production of such pulses and their use in optical pump - X-ray probe measurement. This thesis describes the laser-plasma-based sources available at the University of Duisburg-Essen. Part of it consists of the description of the design, built-up and characterization of a new ''modular'' X-ray source dedicated to optimize the X-ray flux onto the sample under investigation. The acoustic wave generation in femtosecond optically excited semiconductor (gallium arsenide) and metal (gold) was performed using the sources of the University of Duisburg-Essen. The physical answer of the material was modeled by a simple strain model for the semiconductor, pressure model for the metal, in order to gain information on the interplay of the electronic and thermal pressures rising after excitation. Whereas no reliable information could be obtain in gallium arsenide (principally due to the use of a bulk), the model for gold achieved very good agreement, providing useful information. The relaxation time of the electron to lattice energy was found to be (5.0{+-}0.3) ps, and the ratio of the Grueneisen parameters was found to be {gamma}{sub e} / {gamma}{sub i} = (0.5{+-}0.1). This thesis also describes the Sub-Picosecond Pulse Source (SPPS) which existed at the (formally) Stanford Linear Accelerator Center, an accelerator-based X-ray source, and two measurements performed with it. The first one is the detailed investigation of the phonon softening of the A{sub 1g} mode launch in bismuth upon fluence excitation. Detailed information concerning the new equilibrium position and phonon frequency were obtained over extended laser pump fluences. The second measurement concerned the study of the liquid phase dynamics in a newly formed liquid phase following ultrafast melting in indium antimonide. The formation of the liquid phase

  14. An Intraoral Miniature X-ray Tube Based on Carbon Nanotubes for Dental Radiography

    Directory of Open Access Journals (Sweden)

    Hyun Jin Kim

    2016-06-01

    Full Text Available A miniature X-ray tube based on a carbon-nanotube electron emitter has been employed for the application to a dental radiography. The miniature X-ray tube has an outer diameter of 7 mm and a length of 47 mm. The miniature X-ray tube is operated in a negative high-voltage mode in which the X-ray target is electrically grounded. In addition, X-rays are generated only to the teeth directions using a collimator while X-rays generated to other directions are shielded. Hence, the X-ray tube can be safely inserted into a human mouth. Using the intra-oral X-ray tube, a dental radiography is demonstrated where the positions of an X-ray source and a sensor are reversed compared with a conventional dental radiography system. X-ray images of five neighboring teeth are obtained and, furthermore, both left and right molar images are achieved by a single X-ray shot of the miniature X-ray tube.

  15. An intraoral miniature x-ray tube based on carbon nanotubes for dental radiography

    International Nuclear Information System (INIS)

    Kim, Hyun Jin; Kim, Hyun Nam; Raza, Hamid Saeed; Park, Han Beom; Cho, Sung Oh

    2016-01-01

    A miniature X-ray tube based on a carbon-nanotube electron emitter has been employed for the application to a dental radiography. The miniature X-ray tube has an outer diameter of 7 mm and a length of 47 mm. The miniature X-ray tube is operated in a negative high-voltage mode in which the X-ray target is electrically grounded. In addition, X-rays are generated only to the teeth directions using a collimator while X-rays generated to other directions are shielded. Hence, the X-ray tube can be safely inserted into a human mouth. Using the intra-oral X-ray tube, a dental radiography is demonstrated where the positions of an X-ray source and a sensor are reversed compared with a conventional dental radiography system. X-ray images of five neighboring teeth are obtained and, furthermore, both left and right molar images are achieved by a single X-ray shot of the miniature X-ray tube

  16. An intraoral miniature x-ray tube based on carbon nanotubes for dental radiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Jin; Kim, Hyun Nam; Raza, Hamid Saeed; Park, Han Beom; Cho, Sung Oh [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2016-06-15

    A miniature X-ray tube based on a carbon-nanotube electron emitter has been employed for the application to a dental radiography. The miniature X-ray tube has an outer diameter of 7 mm and a length of 47 mm. The miniature X-ray tube is operated in a negative high-voltage mode in which the X-ray target is electrically grounded. In addition, X-rays are generated only to the teeth directions using a collimator while X-rays generated to other directions are shielded. Hence, the X-ray tube can be safely inserted into a human mouth. Using the intra-oral X-ray tube, a dental radiography is demonstrated where the positions of an X-ray source and a sensor are reversed compared with a conventional dental radiography system. X-ray images of five neighboring teeth are obtained and, furthermore, both left and right molar images are achieved by a single X-ray shot of the miniature X-ray tube.

  17. Projection-type X-ray microscope based on a spherical compound refractive X-ray lens

    OpenAIRE

    Dudchik, Yu. I.; Gary, C. K.; Park, H.; Pantell, R. H.; Piestrup, M. A.

    2007-01-01

    New projection- type X-ray microscope with a compound refractive lens as the optical element is presented. The microscope consists of an X-ray source that is 1-2 mm in diameter, compound X-ray lens and X-ray camera that are placed in-line to satisfy the lens formula. The lens forms an image of the X-ray source at camera sensitive plate. An object is placed between the X-ray source and the lens as close as possible to the source, and the camera shows a shadow image of the object. Spatial resol...

  18. Simulation and application of micro X-ray fluorescence based on an ellipsoidal capillary

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jing; Li, Yude; Wang, Xingyi; Zhang, Xiaoyun; Lin, Xiaoyan, E-mail: yangjing_928@126.com

    2017-06-15

    Highlights: • A micro X-ray fluorescence setup based on an ellipsoidal capillary was presented. • The optimal parameters of ellipsoidal capillary were designed. • The 2D mapping image of biological sample was obtained. - Abstract: A micro X-ray fluorescence setup was presented, based on an ellipsoidal capillary and a traditional laboratorial X-ray source. Using Ray-tracing principle, we have simulated the transmission path of X-ray beam in the ellipsoidal capillary and designed the optimal parameters of the ellipsoidal capillary for the micro X-ray fluorescence setup. We demonstrate that ellipsoidal capillary is well suited as condenser for the micro X-ray fluorescence based on traditional laboratorial X-ray source. Furthermore, we obtain the 2D mapping image of the leaf blade sample by using the ellipsoidal capillary we designed.

  19. Measurement of grain size of polycrystalline materials with confocal energy dispersive micro-X-ray diffraction technology based on polycapillary X-ray optics

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Weiyuan; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stx@bnu.edu.cn [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Peng, Song [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Li, Fangzuo; Sun, Xuepeng; Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2014-11-11

    The confocal energy dispersive micro-X-ray diffraction (EDMXRD) based on polycapillary X-ray optics was used to determine the grain size of polycrystalline materials. The grain size of a metallographic specimen of nickel base alloy was measured by using the confocal EDMXRD. The experimental results demonstrated that the confocal EDMXRD had potential applications in measuring large grain size.

  20. X-ray exposure in utero and school performance: a population-based study of X-ray pelvimetry

    International Nuclear Information System (INIS)

    Nordenskjöld, A.C.; Palme, M.; Kaijser, M.

    2015-01-01

    Aim: To investigate the association between exposure to ionising radiation from pelvimetric examinations in utero and school performance. Material and methods: This was a population-based cohort study comprising 46,066 children born in the county of Östergötland, Sweden, from 1980 through 1990. Through record linkage between Swedish registers, children exposed in utero to X-ray pelvimetry examination were compared to other children born in the same county during the study period, as well as to their unexposed siblings. Outcome variable was primary school grades, expressed in centiles and calculated through linear regression. Results: In the univariate analysis, children exposed to X-ray pelvimetry in utero had higher school grades compared to unexposed children (point estimate 3 centiles, 95% confidence interval [CI]: 1.5 to 4.6). When sex, mother's education and income, birth order, and birth position were included in the analysis; however, the difference was reduced and the association was no longer statistically significant (PE 1.4, 95% CI: –0.1 to 2.8). Comparing exposed children with their siblings showed no statistical difference in univariate analysis or in multivariate analysis. Conclusion: No suggestion was found of a negative effect on school performance from in utero exposure of diagnostic X-ray pelvimetry. -- Highlights: •Pelvimetric examinations expose fetus to low levels of radiation. •No detectable effect on childrens final primary school grades from pelvimetric examinations. •Pelvimetric examinations is a safe procedure for the fetus regarding shool performance

  1. X-ray Imaging and preliminary studies of the X-ray self-emission from an innovative plasma-trap based on the Bernstein waves heating mechanism

    Science.gov (United States)

    Caliri, C.; Romano, F. P.; Mascali, D.; Gammino, S.; Musumarra, A.; Castro, G.; Celona, L.; Neri, L.; Altana, C.

    2013-10-01

    Electron Cyclotron Resonance Ion Sources (ECRIS) are based on ECR heated plasmas emitting high fluxes of X-rays. Here we illustrate a pilot study of the X-ray emission from a compact plasma-trap in which an off-resonance microwave-plasma interaction has been attempted, highlighting a possible Bernstein-Waves based heating mechanism. EBWs-heating is obtained via the inner plasma EM-to-ES wave conversion and enables to reach densities much larger than the cut-off ones. At LNS-INFN, an innovative diagnostic technique based on the design of a Pinhole Camera (PHC) coupled to a CCD device for X-ray Imaging of the plasma (XRI) has been developed, in order to integrate X-ray traditional diagnostics (XRS). The complementary use of electrostatic probes measurements and X-ray diagnostics enabled us to gain knowledge about the high energy electrons density and temperature and about the spatial structure of the source. The combination of the experimental data with appropriate modeling of the plasma-source allowed to estimate the X-ray emission intensity in different energy domains (ranging from EUV up to Hard X-rays). The use of ECRIS as X-ray source for multidisciplinary applications, is now a concrete perspective due to the intense fluxes produced by the new plasma heating mechanism.

  2. Low cost ESR based X-ray beamline for lithography experimentation

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, S.; Doumas, A.; Truncale, M. (Grumman Corp., Bethpage, NY (United States). Space and Electronics Div.)

    1992-08-01

    Any application of the electron storage ring (ESR) based X-ray lithography technology requires an X-ray radiation transport system to transfer the synchrotron radiation into a spectrum defined by the lithography process requirements. Structure of this transport system (i.e. the beamline) depends on the nature of the application. In this paper a beamline conceptual design will be discussed. The beamline is intended for the developmment of X-ray lithography technology. (orig.).

  3. A MEMS-based high frequency x-ray chopper

    Energy Technology Data Exchange (ETDEWEB)

    Siria, A; Schwartz, W; Chevrier, J [Institut Neel, CNRS-Universite Joseph Fourier Grenoble, BP 166, F-38042 Grenoble Cedex 9 (France); Dhez, O; Comin, F [ESRF, 6 rue Jules Horowitz, F-38043 Grenoble Cedex 9 (France); Torricelli, G [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

    2009-04-29

    Time-resolved x-ray experiments require intensity modulation at high frequencies (advanced rotating choppers have nowadays reached the kHz range). We here demonstrate that a silicon microlever oscillating at 13 kHz with nanometric amplitude can be used as a high frequency x-ray chopper. We claim that using micro-and nanoelectromechanical systems (MEMS and NEMS), it will be possible to achieve higher frequencies in excess of hundreds of megahertz. Working at such a frequency can open a wealth of possibilities in chemistry, biology and physics time-resolved experiments.

  4. A development of laser-plasma-based soft x-ray microscope system

    International Nuclear Information System (INIS)

    Nam, Ki Yong; Kim, Kyong Woo; Kim, Kyu Gyeom; Kwon, Young Man; Yoon, Kwon Ha

    2003-01-01

    Soft x-ray nano-imaging microscopy system for biomedical application with a high resolution about 50 nm has been designed and described, and its integrated techniques also have been studied. The system is mainly composed of soft x-ray generation system, nano-scaled control system, x-ray optical device like a condenser or object mirror, a CCD camera coupled with multichannel plate (MCP) and vacuum system. In the system, soft x-ray is generated from the laser-based plasma by focusing Nd:YAG laser beam on tantalum (Ta) target. In an x-ray optical system, a wolter mirror has been considering condensing the x-ray beam on a biological specimen and zone plate was adapted as an object mirror. A Si 3 N 4 was used as specimen holder for keeping a biological sample alive in atmosphere conditions. A back-illuminated-CCD camera coupled with multichannel plate was determined to set up.

  5. X-ray structure based evaluation of analogs of citalopram

    DEFF Research Database (Denmark)

    Topiol, Sid; Bang-Andersen, Benny; Sanchez, Connie

    2017-01-01

    The recent publication of X-ray structures of SERT includes structures with the potent antidepressant S-Citalopram (S-Cit). Earlier predictions of ligand binding at both a primary (S1) and an allosteric modulator site (S2), were confirmed. We provide herein examples of a series of Citalopram anal...

  6. Confocal total reflection X-ray fluorescence technology based on an elliptical monocapillary and a parallel polycapillary X-ray optics.

    Science.gov (United States)

    Zhu, Yu; Wang, Yabing; Sun, Tianxi; Sun, Xuepeng; Zhang, Xiaoyun; Liu, Zhiguo; Li, Yufei; Zhang, Fengshou

    2018-07-01

    A total reflection X-ray fluorescence (TXRF) spectrometer based on an elliptical monocapillary X-ray lens (MXRL) and a parallel polycapillary X-ray lens (PPXRL) was designed. This TXRF instrument has micro focal spot, low divergence and high intensity of incident X-ray beam. The diameter of the focal spot of MXRL was 16.5 µm, and the divergence of the incident X-ray beam was 3.4 mrad. We applied this TXRF instrument to the micro analysis of a single-layer film containing Ni deposited on a Si substrate by metal vapor vacuum arc ion source. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Development of a micro-X-ray fluorescence system based on polycapillary X-ray optics for non-destructive analysis of archaeological objects

    Science.gov (United States)

    Cheng, Lin; Ding, Xunliang; Liu, Zhiguo; Pan, Qiuli; Chu, Xuelian

    2007-08-01

    A new micro-X-ray fluorescence (micro-XRF) system based on rotating anode X-ray generator and polycapillary X-ray optics has been set up in XOL Lab, BNU, China, in order to be used for analysis of archaeological objects. The polycapillary X-ray optics used here can focus the primary X-ray beam down to tens of micrometers in diameter that allows for non-destructive and local analysis of sub-mm samples with minor/trace level sensitivity. The analytical characteristics and potential of this micro-XRF system in archaeological research are discussed. Some described uses of this instrument include studying Chinese ancient porcelain.

  8. Development of a micro-X-ray fluorescence system based on polycapillary X-ray optics for non-destructive analysis of archaeological objects

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Lin [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing Radiation Center, Beijing, 100875 (China)], E-mail: chenglin@bnu.edu.cn; Ding Xunliang; Liu Zhiguo; Pan Qiuli; Chu Xuelian [Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing Radiation Center, Beijing, 100875 (China)

    2007-08-15

    A new micro-X-ray fluorescence (micro-XRF) system based on rotating anode X-ray generator and polycapillary X-ray optics has been set up in XOL Lab, BNU, China, in order to be used for analysis of archaeological objects. The polycapillary X-ray optics used here can focus the primary X-ray beam down to tens of micrometers in diameter that allows for non-destructive and local analysis of sub-mm samples with minor/trace level sensitivity. The analytical characteristics and potential of this micro-XRF system in archaeological research are discussed. Some described uses of this instrument include studying Chinese ancient porcelain.

  9. Development and characterization of a laser-based hard x-ray source

    International Nuclear Information System (INIS)

    Tillman, C.

    1996-11-01

    A laser-produced plasma was generated by focusing 100 fs laser pulses, with an energy of 150 mJ, onto metal targets. The laser intensity was expected to reach 10 17 W/cm -2 . Radiation was emitted from the created plasma, with photon energies up to the MeV region. The laser-based X-ray source was optimized, with the purpose of making it a realistic source of hard X-rays (>10 keV). Dedicated equipment was developed for efficient generation and utilization of the hard X-rays. The X-ray source was characterized with respect to its spatial extent and the X-ray yield. Measurements were made of the spectral distribution, by the use of single-photon-counting detectors in different geometries, crystal spectrometers and dose measurements in combination with absorption filters. Ablation of the target material in the laser produced plasma was investigated. Imaging applications have been demonstrated, including ultrafast (picosecond) X-ray imaging, magnification imaging of up to x80, differential imaging in the spectral domain, and imaging of various biological and technical objects. The biological response of ultra-intense X-ray pulses was assessed in cell-culture exposures. The results indicate that the biological response from ultra-intense X-ray exposures is similar to the response with conventional X-ray tubes. 82 refs., 14 figs

  10. Development and characterization of a laser-based hard x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Tillman, C.

    1996-11-01

    A laser-produced plasma was generated by focusing 100 fs laser pulses, with an energy of 150 mJ, onto metal targets. The laser intensity was expected to reach 10{sup 17} W/cm{sup -2}. Radiation was emitted from the created plasma, with photon energies up to the MeV region. The laser-based X-ray source was optimized, with the purpose of making it a realistic source of hard X-rays (>10 keV). Dedicated equipment was developed for efficient generation and utilization of the hard X-rays. The X-ray source was characterized with respect to its spatial extent and the X-ray yield. Measurements were made of the spectral distribution, by the use of single-photon-counting detectors in different geometries, crystal spectrometers and dose measurements in combination with absorption filters. Ablation of the target material in the laser produced plasma was investigated. Imaging applications have been demonstrated, including ultrafast (picosecond) X-ray imaging, magnification imaging of up to x80, differential imaging in the spectral domain, and imaging of various biological and technical objects. The biological response of ultra-intense X-ray pulses was assessed in cell-culture exposures. The results indicate that the biological response from ultra-intense X-ray exposures is similar to the response with conventional X-ray tubes. 82 refs., 14 figs.

  11. JAX: a micro-computer based X-ray diffractometer controller

    International Nuclear Information System (INIS)

    Naval, P.C. Jr.

    1987-05-01

    This paper describes a micro-computer based X-ray diffractometer controller and explores its possibilities in simplifying acquisition and analysis of X-ray powder diffraction data. The interrupt-driven controller can operate in both present time and present count data acquisition modes and allows a data analysis program to execute concurrently with data collection. (Auth.). 16 figs.; 2 tabs

  12. Contextual Multivariate Segmentation of Pork Tissue from Grating-Based Multimodal X-Ray Tomography

    DEFF Research Database (Denmark)

    Einarsdottir, Hildur; Nielsen, Mikkel S.; Ersbøll, Bjarne Kjær

    2013-01-01

    have made novel X-ray image modalities available, where the refraction and scattering of X-rays is obtained simultaneously with the absorption properties, providing enhanced contrast for soft biological tissues. This paper demonstrates how data obtained from grating-based imaging can be segmented...

  13. Status of Kharkov X-ray Generator based on Compton Scattering NESTOR

    NARCIS (Netherlands)

    Zelinsky, A.; Androsov, V.P.; Bulyak, E.V.; Drebot, I.; Gladkikh, P.I.; Grevtsev, V.; Botman, J.I.M.; Ivashchenko, V.; Karnaukhov, I.M.; Lapshin, V.I.; Markov, V.; Mocheshnikov, N.; Mytsykov, A.; Peev, F.A.; Rezaev, A.; Shcherbakov, A.; Skomorkohov, V.; Skyrda, V.; Telegin, Y.; Trotsenko, V.; Tatchyn, R.; Lebedev, B.; Agafonov, A.V.

    2004-01-01

    Nowadays the sources of the X-rays based on a storage ring with low beam energy and Compton scattering of intense laser beam are under development in several laboratories. In the paper the state-of-art in development and construction of cooperative project of a Kharkov advanced X-ray source NESTOR

  14. X-ray microbeams based on Kumakhov polycapillary optics and its

    Indian Academy of Sciences (India)

    Kumakhov polycapillary optics is based on the effective passage of X-ray radiation through bundles of monocapillaries of various configurations. The passage of radiation takes place because of the total external reflection of X-rays from the inner capillary walls. In this work,the basic characteristics of intense quasi-parallel ...

  15. Microprocessor-based system for automatic X-ray diffraction and fluorescence

    International Nuclear Information System (INIS)

    Souza, A.M. de; Carmo, L.C.S. do; Pereira, V.J.E.; Soares, E.A.

    1984-01-01

    A data acquisition and processing device appropriate for X-ray analysis and goniometer control was built. The Z-80 based system as well as the whole architeture is described. The advantages and new possibilities of the automated instrument as compared to the traditional ones are listed. The X-ray diffraction and fluorescence techniques can take advantage of the automation. (Author) [pt

  16. Quality assurance challenges in x-ray emission based analyses

    International Nuclear Information System (INIS)

    Papp, T.

    2005-01-01

    Complete text of publication follows. There is a large scatter in the results of X-ray analysis with solid-state detectors suggesting methodological origin. Although the PIXE (proton induced X-ray emission) analytical technique can work without relation to any physics, as was commented at the recent PIXE conference, one could argue that if the same technique is used for measuring physical quantities reveals problems, then perhaps potential methodological issues can not apriory be excluded. We present a simple example which could be interpreted as indications for methodological considerations. Recently an inter-comparison was made of analysis of the spectra measured at the laboratory of the International Atomic Energy Agency (IAEA). Four participating analytical software packages were used to evaluate the X-ray spectra. There are several thin metal samples spectra, for which common energy scale could not be established. The quality of the spectrum can be judged from the line shape. The line shape is parametrized by the full widths at half maximum (FWHM) of a peak and the so-called low energy tailing. Fitting the spectra individually we obtained FWHM squared values at different energies and determined the linear regression parameters. The parameters suggest a rather poor detector performance. It is generally assumed that the (FWHM) 2 values have a first order polynomial form as a function of X-ray energy. Having done a linear regression analysis, we can plot the standard residual, presented in Fig. 1, which clearly shows a three-sigma deviation. The probability to having a three-sigma deviation is 1%. In other words, the probability that these spectra are in accordance with the expected FWHM functional form is less than 1%. The main problem is that, although the composite spectra were analyzed using four different programs, the difficulty in interpreting the spectra was not commented upon by any of the participants in the inter-comparison. (author)

  17. Characterization of a confocal three-dimensional micro X-ray fluorescence facility based on polycapillary X-ray optics and Kirkpatrick-Baez mirrors

    International Nuclear Information System (INIS)

    Sun Tianxi; Ding Xunliang; Liu Zhiguo; Zhu Guanghua; Li Yude; Wei Xiangjun; Chen Dongliang; Xu Qing; Liu Quanru; Huang Yuying; Lin Xiaoyan; Sun Hongbo

    2008-01-01

    A new confocal three-dimensional micro X-ray fluorescence (3D micro-XRF) facility based on polycapillary X-ray optics in the detection channel and Kirkpatrick-Baez (KB) mirrors in the excitation channel is designed. The lateral resolution (l x , l y ) of this confocal three-dimensional micro-X-ray fluorescence facility is 76.3(l x ) and 53.4(l y ) μm respectively, and its depth resolution d z is 77.1 μm at θ = 90 o . A plant sample (twig of B. microphylla) and airborne particles are analyzed

  18. A New Generation of X-ray Baggage Scanners Based on a Different Physical Principle

    Directory of Open Access Journals (Sweden)

    Robert D. Speller

    2011-10-01

    Full Text Available X-ray baggage scanners play a basic role in the protection of airports, customs, and other strategically important buildings and infrastructures. The current technology of baggage scanners is based on x-ray attenuation, meaning that the detection of threat objects relies on how various objects differently attenuate the x-ray beams going through them. This capability is enhanced by the use of dual-energy x-ray scanners, which make the determination of the x-ray attenuation characteristics of a material more precise by taking images with different x-ray spectra, and combining the information appropriately. However, this still has limitations whenever objects with similar attenuation characteristics have to be distinguished. We describe an alternative approach based on a different x-ray interaction phenomenon, x-ray refraction. Refraction is a familiar phenomenon in visible light (e.g., what makes a straw half immersed in a glass of water appear bent, which also takes place in the x-ray regime, only causing deviations at much smaller angles. Typically, these deviations occur at the boundaries of all objects. We have developed a system that, like other “phase contrast” based instruments, is capable of detecting such deviations, and therefore of creating precise images of the contours of all objects. This complements the material-related information provided by x-ray attenuation, and helps contextualizing the nature of the individual objects, therefore resulting in an increase of both sensitivity (increased detection rate and specificity (reduced rate of false positives of baggage scanners.

  19. X-Ray Computed Tomography of Tranquility Base Moon Rock

    Science.gov (United States)

    Jones, Justin S.; Garvin, Jim; Viens, Mike; Kent, Ryan; Munoz, Bruno

    2016-01-01

    X-ray Computed Tomography (CT) was used for the first time on the Apollo 11 Lunar Sample number 10057.30, which had been previously maintained by the White House, then transferred back to NASA under the care of Goddard Space Flight Center. Results from this analysis show detailed images of the internal structure of the moon rock, including vesicles (pores), crystal needles, and crystal bundles. These crystals, possibly the common mineral ilmenite, are found in abundance and with random orientation. Future work, in particular a greater understanding of these crystals and their formation, may lead to a more in-depth understanding of the lunar surface evolution and mineral content.

  20. Correction method and software for image distortion and nonuniform response in charge-coupled device-based x-ray detectors utilizing x-ray image intensifier

    International Nuclear Information System (INIS)

    Ito, Kazuki; Kamikubo, Hironari; Yagi, Naoto; Amemiya, Yoshiyuki

    2005-01-01

    An on-site method of correcting the image distortion and nonuniform response of a charge-coupled device (CCD)-based X-ray detector was developed using the response of the imaging plate as a reference. The CCD-based X-ray detector consists of a beryllium-windowed X-ray image intensifier (Be-XRII) and a CCD as the image sensor. An image distortion of 29% was improved to less than 1% after the correction. In the correction of nonuniform response due to image distortion, subpixel approximation was performed for the redistribution of pixel values. The optimal number of subpixels was also discussed. In an experiment with polystyrene (PS) latex, it was verified that the correction of both image distortion and nonuniform response worked properly. The correction for the 'contrast reduction' problem was also demonstrated for an isotropic X-ray scattering pattern from the PS latex. (author)

  1. A laboratory based x-ray reflectivity system

    International Nuclear Information System (INIS)

    Holt, S.A.; Creagh, D.C.; Jamie, I.M.; Dowling, T.L.; Brown, A.S.

    1996-01-01

    Full text: X-ray Reflectivity (XRR) over the last decade has proved to be a versatile and powerful technique by which the thickness of thin films, surface roughness and interface roughness can be determined. The systems amenable to study range from organic monolayers (liquid or solid substrates) to layered metal or semiconductor systems. Access to XRR has been limited by the requirement for synchrotron radiation sources. The development of XRR systems for the laboratory environment was pioneered by Weiss. An X-ray Reflectometer has been constructed by the Department of Physics (Australian Defence Force Academy) and the Research School of Chemistry (Australian National University). The general principles of the design were similar to those described by Weiss. The reflectometer is currently in the early stages of commissioning, with encouraging results thus far. The diffraction pattern of Mobil Catalytic Material (MCM), consisting primarily of SiO 2 . The poster will describe the reflectometer, its operation and present a summary of the most important results obtained to date

  2. Advanced Nanoscale Characterization of Cement Based Materials Using X-Ray Synchrotron Radiation: A Review

    KAUST Repository

    Chae, Sejung R.; Moon, Juhyuk; Yoon, Seyoon; Bae, Sungchul; Levitz, Pierre; Winarski, Robert; Monteiro, Paulo J. M.

    2013-01-01

    We report various synchrotron radiation laboratory based techniques used to characterize cement based materials in nanometer scale. High resolution X-ray transmission imaging combined with a rotational axis allows for rendering of samples in three

  3. Ultrafast, laser-based, x-ray science: the dawn of atomic-scale cinematography

    International Nuclear Information System (INIS)

    Barty, C.P.J.

    2000-01-01

    The characteristics of ultrafast chirped pulse amplification systems are reviewed. Application of ultrafast chirped pulse amplification to the generation of femtosecond, incoherent, 8-keV line radiation is outlined and the use of femtosecond laser-based, x-rays for novel time-resolved diffraction studies of crystalline dynamics with sub-picosecond temporal resolution and sub-picometer spatial resolution is reviewed in detail. Possible extensions of laser-based, x-ray technology and evaluation of alternative x-ray approaches for time-resolved studies of the atomic scale dynamics are given. (author)

  4. Development of online cable eccentricity detection system based on X-ray CCD

    International Nuclear Information System (INIS)

    Chen Jianzhen; Li Bin; Wei Kaixia; Guo Lanying; Qu Guopu

    2008-01-01

    An improved technology of online cable eccentricity detection, based on X-ray CCD, greatly improves the measuring precision and the responding speed. The theory of eccentricity measuring based on X-ray CCD, and the structure of an apparatus are described. The apparatus is composed of scanning drive subsystem, X-ray generation components, data acquiring subsystem and high performance computer system. The measuring results are also presented. The features of this cable eccentricity detection technology are compared with the features of other technologies. (authors)

  5. Ultrafast, laser-based, x-ray science: the dawn of atomic-scale cinematography

    Energy Technology Data Exchange (ETDEWEB)

    Barty, C.P.J. [University of California, Department of Applied Mechanics and Engineering Science, Urey Hall, Mali Code 0339, San Diego, La Jolla, CA (United States)

    2000-03-01

    The characteristics of ultrafast chirped pulse amplification systems are reviewed. Application of ultrafast chirped pulse amplification to the generation of femtosecond, incoherent, 8-keV line radiation is outlined and the use of femtosecond laser-based, x-rays for novel time-resolved diffraction studies of crystalline dynamics with sub-picosecond temporal resolution and sub-picometer spatial resolution is reviewed in detail. Possible extensions of laser-based, x-ray technology and evaluation of alternative x-ray approaches for time-resolved studies of the atomic scale dynamics are given. (author)

  6. X-ray CT analysis on archaeological iron based artifacts

    International Nuclear Information System (INIS)

    Honda, Takashi; Gunji, Eiichi

    2005-01-01

    Corrosion analysis was carried out on twenty iron-plates, which had been dug out at the 6th Yamato ancient tomb (Nara-shi). It was evaluated through the inner-structural analysis by X-ray CT and the XRD and chemical analysis of the rusts that the most iron-plates had been buried in a slightly oxidizing environment and the maximum corrosion depth was 1.6 mm for about 1500 years. The analysis result of the extreme-value data indicates that the maximum depth of an overpack is estimated to be 2.5-2.7 mm. A part of small iron-plates were supposed to have been buried in an oxidizing environment, and about 1 mm-thick rust layers with cavities existed and the corrosion amount was figured out to be about 0.3 mm. (author)

  7. Stationary scanning x-ray source based on carbon nanotube field emitters

    International Nuclear Information System (INIS)

    Zhang, J.; Yang, G.; Cheng, Y.; Gao, B.; Qiu, Q.; Lee, Y.Z.; Lu, J.P.; Zhou, O.

    2005-01-01

    We report a field emission x-ray source that can generate a scanning x-ray beam to image an object from multiple projection angles without mechanical motion. The key component of the device is a gated carbon nanotube field emission cathode with an array of electron emitting pixels that are individually addressable via a metal-oxide-semiconductor field effect transistor-based electronic circuit. The characteristics of this x-ray source are measured and its imaging capability is demonstrated. The device can potentially lead to a fast data acquisition rate for laminography and tomosynthesis with a simplified experimental setup

  8. X-Ray Pulsar Based Navigation and Time Determination, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm will build on the Phase I X-ray pulsar-based navigation and timing (XNAV) feasibility assessment to develop a detailed XNAV simulation capability to...

  9. Preparation, characterization and X-ray attenuation property of Gd2O3-based nanocomposites

    Science.gov (United States)

    Jayakumar, Sangeetha; Saravanan, T.; Philip, John

    2017-11-01

    In an attempt to develop an alternate to lead-based X-ray shielding material, we describe the X-ray attenuation property of nanocomposites containing Gd2O3 as nanofiller and silicone resin as matrix, prepared by a simple solution-casting technique. Gd2O3 nanoparticles of size 30 and 56 nm are used at concentrations of 25 and 2.5 wt%. The nanoparticles and the nanocomposites are characterized using X-ray diffraction (XRD) studies, small angle X-ray spectroscopy (SAXS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and atomic force microscopy (AFM). The X-ray attenuation property of nanocomposites, studied using an industrial X-ray unit, shows that nanocomposites containing nanoparticles of size 56 nm (G2) exhibit better attenuation than nanocomposites containing nanoparticles of size 30 nm (G1), which is attributed to the greater interfacial interaction between the G2 nanofillers and silicone matrix. In the case of nanocomposites containing G1 nanoparticles, the interfacial interaction between the nanofiller and the matrix is so weak that it results in pulling out of nanofillers, causing voids in the matrix, which act as X-ray transparent region, thereby reducing the overall X-ray attenuation property of G1 nanocomposites. This is further corroborated from the AFM images of the nanocomposites. The weight loss and heat flow curves of pure silicone matrix and the nanocomposites containing Gd2O3 nanoparticles of size 30 and 56 nm show the degradation of silicone resin, due to chain scission, between 403 and 622 °C. The same onset temperature (403 °C) of degradation of matrix with and without nanoparticles shows that the addition of nanofillers to the matrix does not deteriorate the thermal stability of the matrix. This confirms the thermal stability of nanocomposites. Therefore, our study shows that nanocomposites containing G2 nanoparticles are potential candidates for the development of X-ray opaque fabric material.

  10. A preliminary study of breast cancer diagnosis using laboratory based small angle x-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Round, A R [Daresbury Laboratories, Warrington, WA4 4AD (United Kingdom); Wilkinson, S J [Daresbury Laboratories, Warrington, WA4 4AD (United Kingdom); Hall, C J [Daresbury Laboratories, Warrington, WA4 4AD (United Kingdom); Rogers, K D [Department of Materials and Medical Sciences, Cranfield University, Swindon, SN6 8LA (United Kingdom); Glatter, O [Department of Chemistry, University of Graz (Austria); Wess, T [School of Optometry and Vision Sciences, Cardiff University, Cardiff CF10 3NB, Wales (United Kingdom); Ellis, I O [Nottingham City Hospital, Nottingham (United Kingdom)

    2005-09-07

    Breast tissue collected from tumour samples and normal tissue from bi-lateral mastectomy procedures were examined using small angle x-ray scattering. Previous work has indicated that breast tissue disease diagnosis could be performed using small angle x-ray scattering (SAXS) from a synchrotron radiation source. The technique would be more useful to health services if it could be made to work using a conventional x-ray source. Consistent and reliable differences in x-ray scatter distributions were observed between samples from normal and tumour tissue samples using the laboratory based 'SAXSess' system. Albeit from a small number of samples, a sensitivity of 100% was obtained. This result encourages us to pursue the implementation of SAXS as a laboratory based diagnosis technique.

  11. A preliminary study of breast cancer diagnosis using laboratory based small angle x-ray scattering

    International Nuclear Information System (INIS)

    Round, A R; Wilkinson, S J; Hall, C J; Rogers, K D; Glatter, O; Wess, T; Ellis, I O

    2005-01-01

    Breast tissue collected from tumour samples and normal tissue from bi-lateral mastectomy procedures were examined using small angle x-ray scattering. Previous work has indicated that breast tissue disease diagnosis could be performed using small angle x-ray scattering (SAXS) from a synchrotron radiation source. The technique would be more useful to health services if it could be made to work using a conventional x-ray source. Consistent and reliable differences in x-ray scatter distributions were observed between samples from normal and tumour tissue samples using the laboratory based 'SAXSess' system. Albeit from a small number of samples, a sensitivity of 100% was obtained. This result encourages us to pursue the implementation of SAXS as a laboratory based diagnosis technique

  12. [Study on spectrum analysis of X-ray based on rotational mass effect in special relativity].

    Science.gov (United States)

    Yu, Zhi-Qiang; Xie, Quan; Xiao, Qing-Quan

    2010-04-01

    Based on special relativity, the formation mechanism of characteristic X-ray has been studied, and the influence of rotational mass effect on X-ray spectrum has been given. A calculation formula of the X-ray wavelength based upon special relativity was derived. Error analysis was carried out systematically for the calculation values of characteristic wavelength, and the rules of relative error were obtained. It is shown that the values of the calculation are very close to the experimental values, and the effect of rotational mass effect on the characteristic wavelength becomes more evident as the atomic number increases. The result of the study has some reference meaning for the spectrum analysis of characteristic X-ray in application.

  13. A preliminary study of breast cancer diagnosis using laboratory based small angle x-ray scattering

    Science.gov (United States)

    Round, A. R.; Wilkinson, S. J.; Hall, C. J.; Rogers, K. D.; Glatter, O.; Wess, T.; Ellis, I. O.

    2005-09-01

    Breast tissue collected from tumour samples and normal tissue from bi-lateral mastectomy procedures were examined using small angle x-ray scattering. Previous work has indicated that breast tissue disease diagnosis could be performed using small angle x-ray scattering (SAXS) from a synchrotron radiation source. The technique would be more useful to health services if it could be made to work using a conventional x-ray source. Consistent and reliable differences in x-ray scatter distributions were observed between samples from normal and tumour tissue samples using the laboratory based 'SAXSess' system. Albeit from a small number of samples, a sensitivity of 100% was obtained. This result encourages us to pursue the implementation of SAXS as a laboratory based diagnosis technique.

  14. Simple microprocessor-based system for upgrading existing X-ray equipment for analysis

    International Nuclear Information System (INIS)

    Souza, A.M. de

    1986-01-01

    A data acquisition and processing device appropriate for X-ray analysis and goniometer control was built. A conventional Z-80 based systems was used, and the interfacing architeture and the applicable soft-ware are described. The advantages and new possibilities of the automated instrument as compared to previous ones are listed. It is shown that the X-ray diffraction and fluorescence techniques can take advantage of the automation using existing instruments. (Author) [pt

  15. Wavelet based Image Registration Technique for Matching Dental x-rays

    OpenAIRE

    P. Ramprasad; H. C. Nagaraj; M. K. Parasuram

    2008-01-01

    Image registration plays an important role in the diagnosis of dental pathologies such as dental caries, alveolar bone loss and periapical lesions etc. This paper presents a new wavelet based algorithm for registering noisy and poor contrast dental x-rays. Proposed algorithm has two stages. First stage is a preprocessing stage, removes the noise from the x-ray images. Gaussian filter has been used. Second stage is a geometric transformation stage. Proposed work uses two l...

  16. A nanotube-based field emission x-ray source for microcomputed tomography

    International Nuclear Information System (INIS)

    Zhang, J.; Cheng, Y.; Lee, Y.Z.; Gao, B.; Qiu, Q.; Lin, W.L.; Lalush, D.; Lu, J.P.; Zhou, O.

    2005-01-01

    Microcomputed tomography (micro-CT) is a noninvasive imaging tool commonly used to probe the internal structures of small animals for biomedical research and for the inspection of microelectronics. Here we report the development of a micro-CT scanner with a carbon nanotube- (CNT-) based microfocus x-ray source. The performance of the CNT x-ray source and the imaging capability of the micro-CT scanner were characterized

  17. The application of confocal technology based on polycapillary X-ray optics in surface topography

    International Nuclear Information System (INIS)

    Zhao, Guangcui; Sun, Tianxi; Liu, Zhiguo; Yuan, Hao; Li, Yude; Liu, Hehe; Zhao, Weigang; Zhang, Ruixia; Min, Qin; Peng, Song

    2013-01-01

    A confocal micro-X-ray fluorescence (MXRF) technology based on polycapillary X-ray optics was proposed for determining surface topography. This confocal topography method involves elemental sensitivity and can be used to classify the objects according to their elemental composition while obtaining their surface topography. To improve the spatial resolution of this confocal topography technology, the center of the confocal micro-volume was overlapped with the output focal spot of the polycapillary X-ray, focusing the lens in the excitation channel. The input focal spot of the X-ray lens parallel to the detection channel was used to determine the surface position of the sample. The corresponding surface adaptive algorithm was designed to obtain the surface topography. The surface topography of a ceramic chip was obtained. This confocal MXRF surface topography method could find application in the materials sciences

  18. A Compressed Sensing-based Image Reconstruction Algorithm for Solar Flare X-Ray Observations

    Energy Technology Data Exchange (ETDEWEB)

    Felix, Simon; Bolzern, Roman; Battaglia, Marina, E-mail: simon.felix@fhnw.ch, E-mail: roman.bolzern@fhnw.ch, E-mail: marina.battaglia@fhnw.ch [University of Applied Sciences and Arts Northwestern Switzerland FHNW, 5210 Windisch (Switzerland)

    2017-11-01

    One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new compressed sensing-based algorithm named VIS-CS, which reconstructs the spatial distribution from such Fourier components. We demonstrate the application of the algorithm on synthetic and observed solar flare X-ray data from the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite and compare its performance with existing algorithms. VIS-CS produces competitive results with accurate photometry and morphology, without requiring any algorithm- and X-ray-source-specific parameter tuning. Its robustness and performance make this algorithm ideally suited for the generation of quicklook images or large image cubes without user intervention, such as for imaging spectroscopy analysis.

  19. A Compressed Sensing-based Image Reconstruction Algorithm for Solar Flare X-Ray Observations

    Science.gov (United States)

    Felix, Simon; Bolzern, Roman; Battaglia, Marina

    2017-11-01

    One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new compressed sensing-based algorithm named VIS_CS, which reconstructs the spatial distribution from such Fourier components. We demonstrate the application of the algorithm on synthetic and observed solar flare X-ray data from the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite and compare its performance with existing algorithms. VIS_CS produces competitive results with accurate photometry and morphology, without requiring any algorithm- and X-ray-source-specific parameter tuning. Its robustness and performance make this algorithm ideally suited for the generation of quicklook images or large image cubes without user intervention, such as for imaging spectroscopy analysis.

  20. Photovoltaic X-ray detectors based on epitaxial GaAs structures

    Energy Technology Data Exchange (ETDEWEB)

    Achmadullin, R.A. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation); Artemov, V.V. [Shubnikov Institute of Crystallography, Russian Academy of Sciences, 59 Leninski pr., Moscow B-333, 117333 (Russian Federation); Dvoryankin, V.F. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation)]. E-mail: vfd217@ire216.msk.su; Dvoryankina, G.G. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation); Dikaev, Yu.M. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation); Ermakov, M.G. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation); Ermakova, O.N. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation); Chmil, V.B. [Scientific State Center, High Energy Physics Institute, Protvino, Moscow region (Russian Federation); Holodenko, A.G. [Scientific State Center, High Energy Physics Institute, Protvino, Moscow region (Russian Federation); Kudryashov, A.A.; Krikunov, A.I.; Petrov, A.G.; Telegin, A.A. [Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 1 Ac. Vvedenski square, Fryazino 141190, Moscow region (Russian Federation); Vorobiev, A.P. [Scientific State Center, High Energy Physics Institute, Protvino, Moscow region (Russian Federation)

    2005-12-01

    A new type of the photovoltaic X-ray detector based on epitaxial p{sup +}-n-n'-n{sup +} GaAs structures which provides a high efficiency of charge collection in the non-bias operation mode at room temperature is proposed. The GaAs epitaxial structures were grown by vapor-phase epitaxy on heavily doped n{sup +}-GaAs(1 0 0) substrates. The absorption efficiency of GaAs X-ray detector is discussed. I-V and C-V characteristics of the photovoltaic X-ray detectors are analyzed. The built-in electric field profiles in the depletion region of epitaxial structures are measured by the EBIC method. Charge collection efficiency to {alpha}-particles and {gamma}-radiation are measured. The application of X-ray detectors is discussed.

  1. Schottky x-ray detectors based on a bulk β-Ga2O3 substrate

    Science.gov (United States)

    Lu, Xing; Zhou, Leidang; Chen, Liang; Ouyang, Xiaoping; Liu, Bo; Xu, Jun; Tang, Huili

    2018-03-01

    β-Ga2O3 Schottky barrier diodes (SBDs) have been fabricated on a bulk (100) β-Ga2O3 substrate and tested as X-ray detectors in this study. The devices exhibited good rectification properties, such as a high rectification ratio and a close-to-unity ideality factor. A high photo-to-dark current ratio exceeding 800 was achieved for X-ray detection, which was mainly attributed to the low reverse leakage current in the β-Ga2O3 SBDs. Furthermore, transient response of the β-Ga2O3 X-ray detectors was investigated, and two different detection mechanisms, photovoltaic and photoconductive, were identified. The results imply the great potential of β-Ga2O3 based devices for X-ray detection.

  2. Speckle-based at-wavelength metrology of x-ray optics at Diamond Light Source

    Science.gov (United States)

    Wang, Hongchang; Zhou, Tunhe; Kashyap, Yogesh; Sawhney, Kawal

    2017-08-01

    To achieve high resolution and sensitivity on the nanometer scale, further development of X-ray optics is required. Although ex-situ metrology provides valuable information about X-ray optics, the ultimate performance of X-ray optics is critically dependent on the exact nature of the working conditions. Therefore, it is equally important to perform in-situ metrology at the optics' operating wavelength (`at-wavelength' metrology) to optimize the performance of X-ray optics and correct and minimize the collective distortions of the upstream beamline optics, e.g. monochromator, windows, etc. Speckle-based technique has been implemented and further improved at Diamond Light Source. We have demonstrated that the angular sensitivity for measuring the slope error of an optical surface can reach an accuracy of two nanoradians. The recent development of the speckle-based at-wavelength metrology techniques will be presented. Representative examples of the applications of the speckle-based technique will also be given - including optimization of X-ray mirrors and characterization of compound refraction lenses. Such a high-precision metrology technique will be extremely beneficial for the manufacture and in-situ alignment/optimization of X-ray mirrors for next-generation synchrotron beamlines.

  3. Optimization of X-ray phase-contrast imaging based on in-line holography

    International Nuclear Information System (INIS)

    Wu Xizeng; Liu Hong; Yan Aimin

    2005-01-01

    This paper introduces a newly conceived formalism for clinical in-line phase-contrast X-ray imaging. The new formalism applies not only to ideal 'thin' objects analyzed in previous studies, but also applies to the real-world tissues used in actual clinical practice. Moreover we have identified the four clinically important factors that affect phase-contrast characteristics. These factors are: (1) body part attenuation (2) the spatial coherence of incident X-rays from an X-ray tube (3) the polychromatic nature of the X-ray source and (4) radiation dose to patients for clinical applications. Techniques of phase image-reconstruction based on the new X-ray in-line holography theory are discussed. Numerical simulations are described which were used to validate the theory. The design parameters of an optimal clinical phase-contrast mammographic imaging system which were determined based on the new theory, and validated in the simulations, are presented. The theory, image reconstruction algorithms, and numerical simulation techniques presented in this paper can be applied widely to clinical diagnostic X-ray imaging applications

  4. Studies of oxide-based thin-layered heterostructures by X-ray scattering methods

    Energy Technology Data Exchange (ETDEWEB)

    Durand, O. [Thales Research and Technology France, Route Departementale 128, F-91767 Palaiseau Cedex (France)]. E-mail: olivier.durand@thalesgroup.com; Rogers, D. [Nanovation SARL, 103 bis rue de Versailles 91400 Orsay (France); Universite de Technologie de Troyes, 10-12 rue Marie Curie, 10010 (France); Teherani, F. Hosseini [Nanovation SARL, 103 bis rue de Versailles 91400 Orsay (France); Andrieux, M. [LEMHE, ICMMOCNRS-UMR 8182, Universite d' Orsay, Batiment 410, 91410 Orsay (France); Modreanu, M. [Tyndall National Institute, Lee Maltings, Prospect Row, Cork (Ireland)

    2007-06-04

    Some X-ray scattering methods (X-ray reflectometry and Diffractometry) dedicated to the study of thin-layered heterostructures are presented with a particular focus, for practical purposes, on the description of fast, accurate and robust techniques. The use of X-ray scattering metrology as a routinely working non-destructive testing method, particularly by using procedures simplifying the data-evaluation, is emphasized. The model-independent Fourier-inversion method applied to a reflectivity curve allows a fast determination of the individual layer thicknesses. We demonstrate the capability of this method by reporting X-ray reflectometry study on multilayered oxide structures, even when the number of the layers constitutive of the stack is not known a-priori. Fast Fourier transform-based procedure has also been employed successfully on high resolution X-ray diffraction profiles. A study of the reliability of the integral-breadth methods in diffraction line-broadening analysis applied to thin layers, in order to determine coherent domain sizes, is also reported. Examples from studies of oxides-based thin-layers heterostructures will illustrate these methods. In particular, X-ray scattering studies performed on high-k HfO{sub 2} and SrZrO{sub 3} thin-layers, a (GaAs/AlOx) waveguide, and a ZnO thin-layer are reported.

  5. Advanced Nanoscale Characterization of Cement Based Materials Using X-Ray Synchrotron Radiation: A Review

    KAUST Repository

    Chae, Sejung R.

    2013-05-22

    We report various synchrotron radiation laboratory based techniques used to characterize cement based materials in nanometer scale. High resolution X-ray transmission imaging combined with a rotational axis allows for rendering of samples in three dimensions revealing volumetric details. Scanning transmission X-ray microscope combines high spatial resolution imaging with high spectral resolution of the incident beam to reveal X-ray absorption near edge structure variations in the material nanostructure. Microdiffraction scans the surface of a sample to map its high order reflection or crystallographic variations with a micron-sized incident beam. High pressure X-ray diffraction measures compressibility of pure phase materials. Unique results of studies using the above tools are discussed-a study of pores, connectivity, and morphology of a 2,000 year old concrete using nanotomography; detection of localized and varying silicate chain depolymerization in Al-substituted tobermorite, and quantification of monosulfate distribution in tricalcium aluminate hydration using scanning transmission X-ray microscopy; detection and mapping of hydration products in high volume fly ash paste using microdiffraction; and determination of mechanical properties of various AFm phases using high pressure X-ray diffraction. © 2013 The Author(s).

  6. Development and evaluation of gallium nitride-based thin films for x-ray dosimetry

    International Nuclear Information System (INIS)

    Hofstetter, Markus; Thalhammer, Stefan; Howgate, John; Sharp, Ian D; Stutzmann, Martin

    2011-01-01

    X-ray radiation plays an important role in medical procedures ranging from diagnostics to therapeutics. Due to the harm such ionizing radiation can cause, it has become common practice to closely monitor the dosages received by patients. To this end, precise online dosimeters have been developed with the dual objectives of monitoring radiation in the region of interest and improving therapeutic methods. In this work, we evaluate GaN thin film high electron mobility heterostructures with sub-mm 2 detection areas as x-ray radiation detectors. Devices were tested using 40-300 kV Bremsstrahlung x-ray sources. We find that the photoconductive device response exhibits a large gain, is almost independent of the angle of irradiation, and is constant to within 2% of the signal throughout this medical diagnostic x-ray range, indicating that these sensors do not require recalibration for geometry or energy. Furthermore, the devices show a high sensitivity to x-ray intensity and can measure in the air kerma rate (free-in-air) range of 1 μGy s -1 to 10 mGy s -1 with a signal stability of ±1% and a linear total dose response over time. Medical conditions were simulated by measurements of device responses to irradiation through human torso phantoms. Direct x-ray imaging is demonstrated using the index finger and wrist sections of a human phantom. The results presented here indicate that GaN-based thin film devices exhibit a wide range of properties, which make them promising candidates for dosimetry applications. In addition, with potential detection volumes smaller than 10 -6 cm 3 , they are well suited for high-resolution x-ray imaging. Moreover, with additional engineering steps, these devices can be adapted to potentially provide both in vivo biosensing and x-ray dosimetry.

  7. Industrial X-ray imaging based on scintillators and CMOS APS array: direct X-ray irradiation effects

    International Nuclear Information System (INIS)

    Kim, Kwang Hyun; Jeon, Sung Chae; Kim, Young Soo; Cho, Gyuseong

    2005-01-01

    To see the effects of the direct X-ray in a Lanex screen-coupled CMOS APS imager, we measured modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE). These measurements were performed under the condition of non-destructive test (NDT). By increasing the cumulative exposure on the imager, the MTF was degraded, and also leading to the DQE degradation. Each parameter changed by the exposure is described in detail

  8. Diagnosing and mapping pulmonary emphysema on X-ray projection images: incremental value of grating-based X-ray dark-field imaging.

    Science.gov (United States)

    Meinel, Felix G; Schwab, Felix; Schleede, Simone; Bech, Martin; Herzen, Julia; Achterhold, Klaus; Auweter, Sigrid; Bamberg, Fabian; Yildirim, Ali Ö; Bohla, Alexander; Eickelberg, Oliver; Loewen, Rod; Gifford, Martin; Ruth, Ronald; Reiser, Maximilian F; Pfeiffer, Franz; Nikolaou, Konstantin

    2013-01-01

    To assess whether grating-based X-ray dark-field imaging can increase the sensitivity of X-ray projection images in the diagnosis of pulmonary emphysema and allow for a more accurate assessment of emphysema distribution. Lungs from three mice with pulmonary emphysema and three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Median signal intensities of transmission (T), dark-field (V) and a combined parameter (normalized scatter) were compared between emphysema and control group. To determine the diagnostic value of each parameter in differentiating between healthy and emphysematous lung tissue, a receiver-operating-characteristic (ROC) curve analysis was performed both on a per-pixel and a per-individual basis. Parametric maps of emphysema distribution were generated using transmission, dark-field and normalized scatter signal and correlated with histopathology. Transmission values relative to water were higher for emphysematous lungs than for control lungs (1.11 vs. 1.06, pemphysema provides color-coded parametric maps, which show the best correlation with histopathology. In a murine model, the complementary information provided by X-ray transmission and dark-field images adds incremental diagnostic value in detecting pulmonary emphysema and visualizing its regional distribution as compared to conventional X-ray projections.

  9. A set-up of micro-X-ray fluorescence system based on polycapillary X-ray optics and applications for archaeology

    International Nuclear Information System (INIS)

    Cheng Lin; Pan Qiuli; Ding Xunliang; Liu Zhiguo

    2008-01-01

    The paper concerns in the structures, performances and characteristics and applications for archaeology of a new micro-X-ray fluorescence system based on rotating anode X-ray generator and polycapillary X-ray optics. The polycapillary X-ray optics used here can focus the primary X-ray beam down to some tens of micrometers in diameters that allows for non-destructive and local analysis of sub-mm samples with minor/ trace level sensitivity. In order to prove the potentials of this instrument used in archaeology, a piece of Chinese ancient blue and white porcelain produced in Ming Dynasty was analyzed. The results show that intensities of Mn-Kα, Co-Kα are variable in agree with the thick of blue glaze. The correlation analysis indicates the Mn and Co have the best correlations. So, the concentrations or ratios of Mn and Co are crucial to determine the provenance and identify from a fake one of Chinese ancient blue and white porcelain. (authors)

  10. Study on two-dimensional distribution of X-ray image based on improved Elman algorithm

    International Nuclear Information System (INIS)

    Wang, Fang; Wang, Ming-Yuan; Tian, Feng-Shuo; Liu, Yu-Fang; Li, Lei; Zhao, Jing

    2015-01-01

    The principle of the X-ray detector which can simultaneously perform the measurement of the exposure rate and 2D (two-dimensional) distribution is described. A commercially available CMOS image sensor has been adopted as the key part to receive X-ray without any scintillators. The correlation between the pixel value (PV) and the absorbed exposure rate of X-ray is studied using the improved Elman neural network. Comparing the optimal adjustment process of the BP (Back Propagation) neural network and the improved Elman neural network, the neural network parameters are selected based on the fitting curve and the error curve. The experiments using the practical production data show that the proposed method achieves high accurate predictions to 10 −15 , which is consistent with the anticipated value. It is proven that it is possible to detect the exposure rate using the X-ray detector with the improved Elman algorithm for its advantages of fast converges and smooth error curve. - Highlights: • A method to measure the X-ray radiation with low cost and miniaturization. • A general CMOS image sensor is used to detect X-ray. • The system can measure exposure rate and 2D distribution simultaneously. • The Elman algorithm is adopted to improve the precision of the radiation detector

  11. A development of laser-plasma-based soft x-ray microscope system

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ki Yong; Kim, Kyong Woo; Kim, Kyu Gyeom; Kwon, Young Man; Yoon, Kwon Ha [X-ray Microscopy Research Center, Wonkwang University, Iksan (Korea, Republic of)

    2003-07-01

    Soft x-ray nano-imaging microscopy system for biomedical application with a high resolution about 50 nm has been designed and described, and its integrated techniques also have been studied. The system is mainly composed of soft x-ray generation system, nano-scaled control system, x-ray optical device like a condenser or object mirror, a CCD camera coupled with multichannel plate (MCP) and vacuum system. In the system, soft x-ray is generated from the laser-based plasma by focusing Nd:YAG laser beam on tantalum (Ta) target. In an x-ray optical system, a wolter mirror has been considering condensing the x-ray beam on a biological specimen and zone plate was adapted as an object mirror. A Si{sub 3}N{sub 4} was used as specimen holder for keeping a biological sample alive in atmosphere conditions. A back-illuminated-CCD camera coupled with multichannel plate was determined to set up.

  12. Development of full-field x-ray phase-tomographic microscope based on laboratory x-ray source

    Science.gov (United States)

    Takano, H.; Wu, Y.; Momose, A.

    2017-09-01

    An X-ray phase tomographic microscope that can quantitatively measure the refractive index of a sample in three dimensions with a high spatial resolution was developed by installing a Lau interferometer consisting of an absorption grating and a π/2 phase grating into the optics of an X-ray microscope. The optics comprises a Cu rotating anode X-ray source, capillary condenser optics, and a Fresnel zone plate for the objective. The microscope has two optical modes: a large-field-of-view mode (field of view: 65 μm x 65 μm) and a high-resolution mode (spatial resolution: 50 nm). Optimizing the parameters of the interferometer yields a self-image of the phase grating with 60% visibility. Through the normal fringe-scanning measurement, a twin phase image, which has an overlap of two phase image of opposite contrast with a shear distance much larger than system resolution, is generated. Although artifacts remain to some extent currently when a phase image is calculated from the twin phase image, this system can obtain high-spatial-resolution images resolving 50-nm structures. Phase tomography with this system has also been demonstrated using a phase object.

  13. The x-ray time of flight method for investigation of ghosting in amorphous selenium-based flat panel medical x-ray imagers

    International Nuclear Information System (INIS)

    Rau, A.W.; Bakueva, L.; Rowlands, J.A.

    2005-01-01

    Amorphous selenium (a-Se) based real-time flat-panel imagers (FPIs) are finding their way into the digital radiology department because they offer the practical advantages of digital x-ray imaging combined with an image quality that equals or outperforms that of conventional systems. The temporal imaging characteristics of FPIs can be affected by ghosting (i.e., radiation-induced changes of sensitivity) when the dose to the detector is high (e.g., portal imaging and mammography) or the images are acquired at a high frame rate (e.g., fluoroscopy). In this paper, the x-ray time-of-flight (TOF) method is introduced as a tool for the investigation of ghosting in a-Se photoconductor layers. The method consists of irradiating layers of a-Se with short x-ray pulses. From the current generated in the a-Se layer, ghosting is quantified and the ghosting parameters (charge carrier generation rate and carrier lifetimes and mobilities) are assessed. The x-ray TOF method is novel in that (1) x-ray sensitivity (S) and ghosting parameters can be measured simultaneously (2) the transport of both holes and electrons can be isolated, and (3) the method is applicable to the practical a-Se layer structure with blocking contacts used in FPIs. The x-ray TOF method was applied to an analysis of ghosting in a-Se photoconductor layers under portal imaging conditions, i.e., 1 mm thick a-Se layers, biased at 5 V/μm, were irradiated using a 6 MV LINAC x-ray beam to a total dose (ghosting dose) of 30 Gy. The initial sensitivity (S 0 ) of the a-Se layers was 63±2 nC cm -2 cGy -1 . It was found that S decreases to 30% of S 0 after a ghosting dose of 5 Gy and to 21% after 30 Gy at which point no further change in S occurs. At an x-ray intensity of 22 Gy/s (instantaneous dose rate during a LINAC x-ray pulse), the charge carrier generation rate was 1.25±0.1x10 22 ehp m -3 s -1 and, to a first approximation, independent of the ghosting dose. However, both hole and electron transport showed a

  14. Web-based X-ray quality control documentation.

    Science.gov (United States)

    David, George; Burnett, Lou Ann; Schenkel, Robert

    2003-01-01

    The department of radiology at the Medical College of Georgia Hospital and Clinics has developed an equipment quality control web site. Our goal is to provide immediate access to virtually all medical physics survey data. The web site is designed to assist equipment engineers, department management and technologists. By improving communications and access to equipment documentation, we believe productivity is enhanced. The creation of the quality control web site was accomplished in three distinct steps. First, survey data had to be placed in a computer format. The second step was to convert these various computer files to a format supported by commercial web browsers. Third, a comprehensive home page had to be designed to provide convenient access to the multitude of surveys done in the various x-ray rooms. Because we had spent years previously fine-tuning the computerization of the medical physics quality control program, most survey documentation was already in spreadsheet or database format. A major technical decision was the method of conversion of survey spreadsheet and database files into documentation appropriate for the web. After an unsatisfactory experience with a HyperText Markup Language (HTML) converter (packaged with spreadsheet and database software), we tried creating Portable Document Format (PDF) files using Adobe Acrobat software. This process preserves the original formatting of the document and takes no longer than conventional printing; therefore, it has been very successful. Although the PDF file generated by Adobe Acrobat is a proprietary format, it can be displayed through a conventional web browser using the freely distributed Adobe Acrobat Reader program that is available for virtually all platforms. Once a user installs the software, it is automatically invoked by the web browser whenever the user follows a link to a file with a PDF extension. Although no confidential patient information is available on the web site, our legal

  15. X-ray-based attenuation correction for positron emission tomography/computed tomography scanners.

    Science.gov (United States)

    Kinahan, Paul E; Hasegawa, Bruce H; Beyer, Thomas

    2003-07-01

    A synergy of positron emission tomography (PET)/computed tomography (CT) scanners is the use of the CT data for x-ray-based attenuation correction of the PET emission data. Current methods of measuring transmission use positron sources, gamma-ray sources, or x-ray sources. Each of the types of transmission scans involves different trade-offs of noise versus bias, with positron transmission scans having the highest noise but lowest bias, whereas x-ray scans have negligible noise but the potential for increased quantitative errors. The use of x-ray-based attenuation correction, however, has other advantages, including a lack of bias introduced from post-injection transmission scanning, which is an important practical consideration for clinical scanners, as well as reduced scan times. The sensitivity of x-ray-based attenuation correction to artifacts and quantitative errors depends on the method of translating the CT image from the effective x-ray energy of approximately 70 keV to attenuation coefficients at the PET energy of 511 keV. These translation methods are usually based on segmentation and/or scaling techniques. Errors in the PET emission image arise from positional mismatches caused by patient motion or respiration differences between the PET and CT scans; incorrect calculation of attenuation coefficients for CT contrast agents or metallic implants; or keeping the patient's arms in the field of view, which leads to truncation and/or beam-hardening (or x-ray scatter) artifacts. Proper interpretation of PET emission images corrected for attenuation by using the CT image relies on an understanding of the potential artifacts. In cases where an artifact or bias is suspected, careful inspection of all three available images (CT and PET emission with and without attenuation correction) is recommended. Copyright 2003 Elsevier Inc. All rights reserved.

  16. The practical training of students - x-ray technicians and requirements to mentors in clinical bases

    International Nuclear Information System (INIS)

    Gagova, P; Boninska, N.; Jovchev, D.

    2012-01-01

    Full text: Introduction: Training of X-ray technicians in Bulgaria takes place in the Medical Colleges to Medical Universities. It's purpose is providing professional training of students in the area of diagnostic imaging, nuclear medicine and radiotherapy. Practical training is based on the scientific and theoretical knowledge and skills and is organized in pedagogic environment, adequate to regularities for a gradual formation of practical skills and habits. The practical training and pre-graduation internship are performed in 1895 from total of 3810 hours, which represents about fifty percent of all training of X-ray technicians. Students are in groups of 2-4 students. Practical training is organized, accomplished and monitored by the teacher training practice with the help of a mentor in the clinical base. Purpose: To present the tasks of practical training of students - X-ray technicians and the requirements for the personal characteristics and activity of mentors. Materials and methods: Documentary method has been used. Literature and normative documents related to the practical training of students in 'X-ray technician' of Medical Colleges have been studied. The job descriptions of senior clinical X-ray technicians have been examined carefully. Results: By analyzing literature sources, we have structured the tasks of practical training and pre-graduation internship of students - X-ray technicians, also we have described the requirements for personal qualities of mentors and systematize the activities they perform. Conclusion: Practical training plays an important role in adaptation of young X-ray technicians to the conditions of medical work, improving their skills and habits, and to the development of specific practical skills for being able to respond to emergency conditions and to solve complicated practical situations. The mentor is the supervisor and the controller of interns who helps this happen through his own example, qualities and attitudes towards

  17. X-ray photoemission spectroscopy (XPS) and extended x-ray absorption fine structure (EXAFS) studies of silicate based glasses

    International Nuclear Information System (INIS)

    Karim, D.; Lam, D.J.

    1979-01-01

    The application of the x-ray photoemission spectroscopy (XPS) technique to study the electronic structure and bonding of heavy metal oxides in alkali- and alkali-earth-silicate glasses had been demonstrated. The bonding characteristics of the iron oxide and uranium oxide in sodium silicate glasses were deduced from the changes in the oxygen 1s levels and the heavy metal core levels. It is reasonable to expect that the effect of leaching on the heavy metal ions can be monitored using the appropriate core levels of these ions. To study the effect of leaching on the glass forming network, the valence band structure of the bridging and nonbridging oxygens in sodium silicate glasses were investigated. The measurement of extended x-ray absorption fine-structure (EXAFS) is a relatively new analytical technique for obtaining short range (<5 A) structural information around atoms of a selected species in both solid and fluid systems. Experiments have recently begun to establish the feasibility of using EXAFS to study the bonding of actinides in silicate glasses. Because of the ability of EXAFS to yield specific structural data even in complex multicomponent systems, it could prove to be an invaluable tool in understanding glass structure

  18. Automated and observer based light field indicator edge evaluation in diagnostic X-ray equipment

    Directory of Open Access Journals (Sweden)

    Márcio Bottaro

    Full Text Available Abstract Introduction To analyze edge detection and optical contrast calculation of light field-indicators used in X-ray via automated- and observer-based methods, and comparison with current standard approaches, which do not give exact definition for light field edge determination. Methods Automated light sensor array was used to measure the penumbra zone of the edge in the standard X-ray equipment, while trained and naïve human observers were asked to mark the light field edge according to their own determination. Different interpretations of the contrast were then calculated and compared. Results In contrast to automated measurements of edge definition and detection, measurements by human observers showed large inter-observer variation independent of their training with X-ray equipment. Different contrast calculations considering the different edge definitions gave very different contrast values. Conclusion As the main conclusion, we propose a more exact edge definition of the X-ray light field, corresponding well to the average human observer’s edge determination. The new edge definition method with automated systems would reduce human variability in edge determination. Such errors could potentially affect the approval of X-ray equipment, and also increase the radiation dose. The automated measurement based on human observers’ edge definition and the corresponding contrast calculation may lead to a more precise light field calibration, which enables reduced irradiation doses on radiology patients.

  19. A Recirculating Linac-Based Facility for Ultrafast X-Ray Science

    International Nuclear Information System (INIS)

    Corlett, J. N.; Barletta, W. A.; DeSantis, S.; Doolittle, L.; Fawley, W. M.; Green, M.A.; Heimann, P.; Leone, S.; Lidia, S.; Li, D.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wolski, A.; Zholents, A.; Parmigiani, F.; Placidi, M.; Pirkl, W.; Rimmer, R. A.; Wang, S.

    2003-01-01

    We present an updated design for a proposed source of ultra-fast synchrotron radiation pulses based on a recirculating superconducting linac [1,2], in particular the incorporation of EUV and soft x-ray production. The project has been named LUX--Linac-based Ultrafast X-ray facility. The source produces intense x-ray pulses with duration of 10-100 fs at a 10 kHz repetition rate, with synchronization of 10's fs, optimized for the study of ultra-fast dynamics. The photon range covers the EUV to hard x-ray spectrum by use of seeded harmonic generation in undulators, and a specialized technique for ultra-short pulse photon production in the 1-10 keV range. High brightness rf photocathodes produce electron bunches which are optimized either for coherent emission in free electron lasers, or to provide a large x/y emittance ration and small vertical emittance which allows for manipulation to produce short-pulse hard x-rays. An injector linac accelerates the beam to 120 MeV, and is followed by f our passes through a 600-720 MeV recirculating linac. We outline the major technical components of the proposed facility

  20. Automated and observer based light field indicator edge evaluation in diagnostic X-ray equipment

    International Nuclear Information System (INIS)

    Bottaro, Marcio; Nagy, Balazs Vince; Soares, Fernanda Cristina Salvador; Rosendo, Danilo Cabral

    2017-01-01

    Introduction: To analyze edge detection and optical contrast calculation of light field-indicators used in X-ray via automated- and observer-based methods, and comparison with current standard approaches, which do not give exact definition for light field edge determination. Methods: Automated light sensor array was used to measure the penumbra zone of the edge in the standard X-ray equipment, while trained and naive human observers were asked to mark the light field edge according to their own determination. Different interpretations of the contrast were then calculated and compared. Results: In contrast to automated measurements of edge definition and detection, measurements by human observers showed large inter-observer variation independent of their training with X-ray equipment. Different contrast calculations considering the different edge definitions gave very different contrast values. Conclusion: As the main conclusion, we propose a more exact edge definition of the X-ray light field, corresponding well to the average human observer's edge determination. The new edge definition method with automated systems would reduce human variability in edge determination. Such errors could potentially affect the approval of X-ray equipment, and also increase the radiation dose. The automated measurement based on human observers’ edge definition and the corresponding contrast calculation may lead to a more precise light field calibration, which enables reduced irradiation doses on radiology patients. (author)

  1. Automated and observer based light field indicator edge evaluation in diagnostic X-ray equipment

    Energy Technology Data Exchange (ETDEWEB)

    Bottaro, Marcio; Nagy, Balazs Vince; Soares, Fernanda Cristina Salvador; Rosendo, Danilo Cabral, E-mail: marcio@iee.usp.br [Universidade de Sao Paulo (USP), SP (Brazil); Optics and Engineering Informatics, Budapest University of Technology and Economics, Budapest (Hungary)

    2017-04-15

    Introduction: To analyze edge detection and optical contrast calculation of light field-indicators used in X-ray via automated- and observer-based methods, and comparison with current standard approaches, which do not give exact definition for light field edge determination. Methods: Automated light sensor array was used to measure the penumbra zone of the edge in the standard X-ray equipment, while trained and naive human observers were asked to mark the light field edge according to their own determination. Different interpretations of the contrast were then calculated and compared. Results: In contrast to automated measurements of edge definition and detection, measurements by human observers showed large inter-observer variation independent of their training with X-ray equipment. Different contrast calculations considering the different edge definitions gave very different contrast values. Conclusion: As the main conclusion, we propose a more exact edge definition of the X-ray light field, corresponding well to the average human observer's edge determination. The new edge definition method with automated systems would reduce human variability in edge determination. Such errors could potentially affect the approval of X-ray equipment, and also increase the radiation dose. The automated measurement based on human observers’ edge definition and the corresponding contrast calculation may lead to a more precise light field calibration, which enables reduced irradiation doses on radiology patients. (author)

  2. Grating-based X-ray phase contrast for biomedical imaging applications

    International Nuclear Information System (INIS)

    Pfeiffer, Franz; Willner, Marian; Chabior, Michael; Herzen, Julia; Helmholtz-Zentrum Geesthacht, Geesthacht; Auweter, Sigrid; Reiser, Maximilian; Bamberg, Fabian

    2013-01-01

    In this review article we describe the development of grating-based X-ray phase-contrast imaging, with particular emphasis on potential biomedical applications of the technology. We review the basics of image formation in grating-based phase-contrast and dark-field radiography and present some exemplary multimodal radiography results obtained with laboratory X-ray sources. Furthermore, we discuss the theoretical concepts to extend grating-based multimodal radiography to quantitative transmission, phase-contrast, and dark-field scattering computed tomography. (orig.)

  3. A structural study of bone changes in knee osteoarthritis by synchrotron-based X-ray fluorescence and X-ray absorption spectroscopy techniques

    Science.gov (United States)

    Sindhupakorn, Bura; Thienpratharn, Suwittaya; Kidkhunthod, Pinit

    2017-10-01

    Osteoarthritis (OA) is characterized by degeneration of articular cartilage and thickening of subchondral bone. The present study investigated the changing of biochemical components of cartilage and bone compared between normal and OA people. Using Synchrotron-based X-ray fluorescence (SR-XRF) and X-ray absorption spectroscopy (XAS) techniquesincluding X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) were employed for the bone changes in kneeosteoarthritisstudies. The bone samples were collected from various osteoarthritis patients with both male and female in the ages range between 20 and 74 years old. SR-XRF results excited at 4240 eV for Ca elements show a majority three main groups, based on their XRF intensities, 20-36 years, 40-60 years and over 70 years, respectively. By employing XAS techniques, XANES features can be used to clearly explain in term of electronic transitions occurring in bone samples which are affected from osteoarthritis symptoms. Moreover, a structural change around Ca ions in bone samples is obviously obtained by EXAFS results indicating an increase of Ca-amorphous phase when the ages increase.

  4. Low-dose multiple-information retrieval algorithm for X-ray grating-based imaging

    International Nuclear Information System (INIS)

    Wang Zhentian; Huang Zhifeng; Chen Zhiqiang; Zhang Li; Jiang Xiaolei; Kang Kejun; Yin Hongxia; Wang Zhenchang; Stampanoni, Marco

    2011-01-01

    The present work proposes a low dose information retrieval algorithm for X-ray grating-based multiple-information imaging (GB-MII) method, which can retrieve the attenuation, refraction and scattering information of samples by only three images. This algorithm aims at reducing the exposure time and the doses delivered to the sample. The multiple-information retrieval problem in GB-MII is solved by transforming a nonlinear equations set to a linear equations and adopting the nature of the trigonometric functions. The proposed algorithm is validated by experiments both on conventional X-ray source and synchrotron X-ray source, and compared with the traditional multiple-image-based retrieval algorithm. The experimental results show that our algorithm is comparable with the traditional retrieval algorithm and especially suitable for high Signal-to-Noise system.

  5. Recent advances in synchrotron-based hard x-ray phase contrast imaging

    Science.gov (United States)

    Liu, Y.; Nelson, J.; Holzner, C.; Andrews, J. C.; Pianetta, P.

    2013-12-01

    Ever since the first demonstration of phase contrast imaging (PCI) in the 1930s by Frits Zernike, people have realized the significant advantage of phase contrast over conventional absorption-based imaging in terms of sensitivity to ‘transparent’ features within specimens. Thus, x-ray phase contrast imaging (XPCI) holds great potential in studies of soft biological tissues, typically containing low Z elements such as C, H, O and N. Particularly when synchrotron hard x-rays are employed, the favourable brightness, energy tunability, monochromatic characteristics and penetration depth have dramatically enhanced the quality and variety of XPCI methods, which permit detection of the phase shift associated with 3D geometry of relatively large samples in a non-destructive manner. In this paper, we review recent advances in several synchrotron-based hard x-ray XPCI methods. Challenges and key factors in methodological development are discussed, and biological and medical applications are presented.

  6. Recent advances in synchrotron-based hard x-ray phase contrast imaging

    International Nuclear Information System (INIS)

    Liu, Y; Nelson, J; Andrews, J C; Pianetta, P; Holzner, C

    2013-01-01

    Ever since the first demonstration of phase contrast imaging (PCI) in the 1930s by Frits Zernike, people have realized the significant advantage of phase contrast over conventional absorption-based imaging in terms of sensitivity to ‘transparent’ features within specimens. Thus, x-ray phase contrast imaging (XPCI) holds great potential in studies of soft biological tissues, typically containing low Z elements such as C, H, O and N. Particularly when synchrotron hard x-rays are employed, the favourable brightness, energy tunability, monochromatic characteristics and penetration depth have dramatically enhanced the quality and variety of XPCI methods, which permit detection of the phase shift associated with 3D geometry of relatively large samples in a non-destructive manner. In this paper, we review recent advances in several synchrotron-based hard x-ray XPCI methods. Challenges and key factors in methodological development are discussed, and biological and medical applications are presented. (paper)

  7. Characterization of LiF-based soft X-ray imaging detectors by confocal fluorescence microscopy

    International Nuclear Information System (INIS)

    Bonfigli, F; Gaudio, P; Lupelli, I; Nichelatti, E; Richetta, M; Vincenti, M A; Montereali, R M

    2010-01-01

    X-ray microscopy represents a powerful tool to obtain images of samples with very high spatial resolution. The main limitation of this technique is represented by the poor spatial resolution of standard imaging detectors. We proposed an innovative high-performance X-ray imaging detector based on the visible photoluminescence of colour centres in lithium fluoride. In this work, a confocal microscope in fluorescence mode was used to characterize LiF-based imaging detectors measuring CC integrated visible fluorescence signals of LiF crystals and films (grown on several kinds of substrates) irradiated by soft X-rays produced by a laser plasma source in different exposure conditions. The results are compared with the CC photoluminescence spectra measured on the same samples and discussed.

  8. Development of Compact Soft X-ray Source Based on Laser Undulator

    CERN Document Server

    Kuroda, Ryunosuke; Minamiguchi, S; Saitô, T; Ueyama, D; Washio, Masakazu

    2004-01-01

    A compact soft X-ray source is required in various research fields such as material and biological science. The laser undulator based on backward Compton scattering has been developed as a compact soft X-ray source for the biological observation at Waseda University. It is performed in a water window region (250eV - 500 eV) using the interaction between 1047 nm Nd:YLF laser and 4 MeV high quality electron beam generated from rf gun system. The range of energy in the water window region has K-shell absorption edges of Oxygen, Carbon and Nitrogen, which mainly constitute of living body. Since the absorption coefficient of water is much smaller than the protein’s coefficient in this range, a dehydration of the specimens is not necessary. As a preliminary experiment, about 300 eV X-ray generation was carried out. As next step, soft X-ray optics with zone plate was proposed for Soft X-ray microscopy. In this conference, we will report details and results of the experiment.

  9. Synthesis of new nano Schiff base complexes: X-ray crystallography ...

    African Journals Online (AJOL)

    This study presents synthesis and characterization of new nano uranyl Schiff base complexes. Electrochemistry of these complexes showed a quasireversible redox reaction without any successive reactions. Furthermore, X-ray crystallography exhibited that beside the coordination of tetradentate Schiff base, one solvent ...

  10. Network based multi-channel digital flash X-ray imaging system

    International Nuclear Information System (INIS)

    Wang Jingjin; Yuan Jie; Liu Yaqiang; Lin Yong; Song Zheng; Liu Keyin; Zhang Qi; Zheng Futang

    2000-01-01

    A network based multi-channel digital flash X-ray imaging system has been developed. It can be used to acquire and digitize orthogonal flash X-ray images in multi-interval, and to distribute the images on the network. There is no need of films and chemical process, no anxiety of waiting and no trouble of film archiving. This system is useful for testing ballistics, jet, explode, armour-piercing and fast running machines. The system composing and acquired images are presented. The software for object separating, mass calculating, 3D positioning, speed determining and cavity reconstruction are described

  11. Network based multi-channel digital flash X-ray imaging system

    International Nuclear Information System (INIS)

    Wang Jingjin; Yuan Jie; Liu Yaqiang; Lin Yong; Song Zheng; Liu Keyin

    2003-01-01

    A network based multi-channel digital flash X-ray imaging system has been developed. It can be used to acquire and digitize orthogonal flash X-ray images in multi-interval, and to distribute the images on the network. There is no need of films and chemical process, no anxiety of waiting and no trouble of film archiving. This system is useful for testing ballistics, jet, explode, armour-piercing and fast running machines. The system composing and acquired images of terminal ballistics are presented. The software for object separating, profile calculating and 3D cavity reconstruction are described

  12. Automated and observer based light field indicator edge evaluation in diagnostic X-ray equipment

    OpenAIRE

    Bottaro, Márcio; Nagy, Balázs Vince; Soares, Fernanda Cristina Salvador; Rosendo, Danilo Cabral

    2017-01-01

    Abstract Introduction To analyze edge detection and optical contrast calculation of light field-indicators used in X-ray via automated- and observer-based methods, and comparison with current standard approaches, which do not give exact definition for light field edge determination. Methods Automated light sensor array was used to measure the penumbra zone of the edge in the standard X-ray equipment, while trained and naïve human observers were asked to mark the light field edge according t...

  13. X-ray diffraction studies of chitosan acetate-based polymer electrolytes

    International Nuclear Information System (INIS)

    Osman, Z.; Ibrahim, Z.A.; Abdul Kariem Arof

    2002-01-01

    Chitosan is the product when partially deacetylated chitin dissolves in dilute acetic acid. This paper presents the x-ray diffraction patterns of chitosan acetate, plasticised chitosan acetate and plasticised-salted chitosan acetate films. The results show that the chitosan acetate based polymer electrolyte films are not completely amorphous but it is partially crystalline. X-ray diffraction study also confirms the occurrence of the complexation between chitosan and the salt and the interaction between salt and plasticizer. The salt-chitosan interaction is clearly justified by infrared spectroscopy. (Author)

  14. A convolutional neural network-based screening tool for X-ray serial crystallography.

    Science.gov (United States)

    Ke, Tsung Wei; Brewster, Aaron S; Yu, Stella X; Ushizima, Daniela; Yang, Chao; Sauter, Nicholas K

    2018-05-01

    A new tool is introduced for screening macromolecular X-ray crystallography diffraction images produced at an X-ray free-electron laser light source. Based on a data-driven deep learning approach, the proposed tool executes a convolutional neural network to detect Bragg spots. Automatic image processing algorithms described can enable the classification of large data sets, acquired under realistic conditions consisting of noisy data with experimental artifacts. Outcomes are compared for different data regimes, including samples from multiple instruments and differing amounts of training data for neural network optimization. open access.

  15. Hafnium-Based Contrast Agents for X-ray Computed Tomography.

    Science.gov (United States)

    Berger, Markus; Bauser, Marcus; Frenzel, Thomas; Hilger, Christoph Stephan; Jost, Gregor; Lauria, Silvia; Morgenstern, Bernd; Neis, Christian; Pietsch, Hubertus; Sülzle, Detlev; Hegetschweiler, Kaspar

    2017-05-15

    Heavy-metal-based contrast agents (CAs) offer enhanced X-ray absorption for X-ray computed tomography (CT) compared to the currently used iodinated CAs. We report the discovery of new lanthanide and hafnium azainositol complexes and their optimization with respect to high water solubility and stability. Our efforts culminated in the synthesis of BAY-576, an uncharged hafnium complex with 3:2 stoichiometry and broken complex symmetry. The superior properties of this asymmetrically substituted hafnium CA were demonstrated by a CT angiography study in rabbits that revealed excellent signal contrast enhancement.

  16. A CCD-based area detector for X-ray crystallography using synchrotron and laboratory sources

    International Nuclear Information System (INIS)

    Phillips, W.C.; Li Youli; Stanton, M.; Xie Yuanhui; O'Mara, D.; Kalata, K.

    1993-01-01

    The design and characteristics of a CCD-based area detector suitable for X-ray crystallographic studies using both synchrotron and laboratory sources are described. The active area is 75 mm in diameter, the FWHM of the point response function is 0.20 mm, and for Bragg peaks the dynamic range is 900 and the DQE ∼0.3. The 1320x1035-pixel Kodak CCD is read out into an 8 Mbyte memory system in 0.14 s and digitized to 12 bits. X-ray crystallographic data collected at the NSLS synchrotron from cubic insulin crystals are presented. (orig.)

  17. Characteristics of Transmission-type Microfocus X-ray Tube based-on Carbon Nanotube Field Emitter

    International Nuclear Information System (INIS)

    Heo, Sung Hwan; Ihsan, Aamir; Cho, Sung Oh

    2007-01-01

    A high resolution microfocus x-ray source is widely applied to noninvasive detection for industrial demands, material science and engineering, and to diagnostic study of microbiology and micro-tomography. Carbon nanotube (CNT) is regarded as an excellent electron emitter, which outperforms conventional electron sources in point of brightness. It has been suggested that CNT is used as an electron source of a high resolution x-ray tube according to their low threshold field with atomically sharp geometry, chemically robust structure, and electric conductivity. Several researchers have reported miniaturized x-ray tube based on diode structure and micro x-ray radiography and computed tomography systems using triode types with precise emission control and electrostatic focusing. Especially, a microfocus x-ray source of 30 μm resolution has been demonstrated recently using an elliptical CNT cathode and asymmetrical Eingel lens. However, to increase the spatial resolution of x-ray source, a smaller CNT emitter is desired. Electron focusing optics must be corrected to reduce aberrations. A thin wire tip end can provide a micro-area of CNT substrate, and a magnetic lens and transmission x-ray target are proper to reduce the lens aberration and a focal length. Until now, CNT based microfocus x-ray source with less than 10 um resolution has not been shown. Here we report a microfocus x-ray source with 4.7 μm x-ray focal spot consisted of a conical CNT tip, a single solenoid lens, and a transmission type x-ray target. A magnified x-ray image larger than 230 times was resolved with advantage of microfocused focal spot and transmission x-ray target

  18. X-ray repair cross complementing protein 1 in base excision repair

    DEFF Research Database (Denmark)

    Hanssen-Bauer, Audun; Solvang-Garten, Karin; Akbari, Mansour

    2012-01-01

    X-ray Repair Cross Complementing protein 1 (XRCC1) acts as a scaffolding protein in the converging base excision repair (BER) and single strand break repair (SSBR) pathways. XRCC1 also interacts with itself and rapidly accumulates at sites of DNA damage. XRCC1 can thus mediate the assembly of large...

  19. Determination of chest x-ray cost using activity based costing ...

    African Journals Online (AJOL)

    Background: Activity based costing (ABC) is an approach to get insight of true costs and to solve accounting problems. It provides more accurate information on product cost than conventional accounting system. The purpose of this study was to identify detailed resource consumption for chest x-ray procedure. Methods: ...

  20. Grating-based X-ray tomography of 3D food structures

    DEFF Research Database (Denmark)

    Miklos, Rikke; Nielsen, Mikkel Schou; Einarsdottir, Hildur

    2016-01-01

    A novel grating based X-ray phase-contrast tomographic method has been used to study how partly substitution of meat proteins with two different types of soy proteins affect the structure of the formed protein gel in meat emulsions. The measurements were performed at the Swiss synchrotron radiati...

  1. Cone Beam X-ray Luminescence Computed Tomography Based on Bayesian Method.

    Science.gov (United States)

    Zhang, Guanglei; Liu, Fei; Liu, Jie; Luo, Jianwen; Xie, Yaoqin; Bai, Jing; Xing, Lei

    2017-01-01

    X-ray luminescence computed tomography (XLCT), which aims to achieve molecular and functional imaging by X-rays, has recently been proposed as a new imaging modality. Combining the principles of X-ray excitation of luminescence-based probes and optical signal detection, XLCT naturally fuses functional and anatomical images and provides complementary information for a wide range of applications in biomedical research. In order to improve the data acquisition efficiency of previously developed narrow-beam XLCT, a cone beam XLCT (CB-XLCT) mode is adopted here to take advantage of the useful geometric features of cone beam excitation. Practically, a major hurdle in using cone beam X-ray for XLCT is that the inverse problem here is seriously ill-conditioned, hindering us to achieve good image quality. In this paper, we propose a novel Bayesian method to tackle the bottleneck in CB-XLCT reconstruction. The method utilizes a local regularization strategy based on Gaussian Markov random field to mitigate the ill-conditioness of CB-XLCT. An alternating optimization scheme is then used to automatically calculate all the unknown hyperparameters while an iterative coordinate descent algorithm is adopted to reconstruct the image with a voxel-based closed-form solution. Results of numerical simulations and mouse experiments show that the self-adaptive Bayesian method significantly improves the CB-XLCT image quality as compared with conventional methods.

  2. Synchrotron-based X-ray microscopic studies for bioeffects of nanomaterials.

    Science.gov (United States)

    Zhu, Ying; Cai, Xiaoqing; Li, Jiang; Zhong, Zengtao; Huang, Qing; Fan, Chunhai

    2014-04-01

    There have been increasing interests in studying biological effects of nanomaterials, which are nevertheless faced up with many challenges due to the nanoscale dimensions and unique chemical properties of nanomaterials. Synchrotron-based X-ray microscopy, an advanced imaging technology with high spatial resolution and excellent elemental specificity, provides a new platform for studying interactions between nanomaterials and living systems. In this article, we review the recent progress of X-ray microscopic studies on bioeffects of nanomaterials in several living systems including cells, model organisms, animals and plants. We aim to provide an overview of the state of the art, and the advantages of using synchrotron-based X-ray microscopy for characterizing in vitro and in vivo behaviors and biodistribution of nanomaterials. We also expect that the use of a combination of new synchrotron techniques should offer unprecedented opportunities for better understanding complex interactions at the nano-biological interface and accounting for unique bioeffects of nanomaterials. Synchrotron-based X-ray microscopy is a non-destructive imaging technique that enables high resolution spatial mapping of metals with elemental level detection methods. This review summarizes the current use and perspectives of this novel technique in studying the biology and tissue interactions of nanomaterials. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Speckle-based at-wavelength metrology of X-ray mirrors with super accuracy.

    Science.gov (United States)

    Kashyap, Yogesh; Wang, Hongchang; Sawhney, Kawal

    2016-05-01

    X-ray active mirrors, such as bimorph and mechanically bendable mirrors, are increasingly being used on beamlines at modern synchrotron source facilities to generate either focused or "tophat" beams. As well as optical tests in the metrology lab, it is becoming increasingly important to optimise and characterise active optics under actual beamline operating conditions. Recently developed X-ray speckle-based at-wavelength metrology technique has shown great potential. The technique has been established and further developed at the Diamond Light Source and is increasingly being used to optimise active mirrors. Details of the X-ray speckle-based at-wavelength metrology technique and an example of its applicability in characterising and optimising a micro-focusing bimorph X-ray mirror are presented. Importantly, an unprecedented angular sensitivity in the range of two nanoradians for measuring the slope error of an optical surface has been demonstrated. Such a super precision metrology technique will be beneficial to the manufacturers of polished mirrors and also in optimization of beam shaping during experiments.

  4. Speckle-based at-wavelength metrology of X-ray mirrors with super accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Kashyap, Yogesh; Wang, Hongchang; Sawhney, Kawal, E-mail: kawal.sawhney@diamond.ac.uk [Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE (United Kingdom)

    2016-05-15

    X-ray active mirrors, such as bimorph and mechanically bendable mirrors, are increasingly being used on beamlines at modern synchrotron source facilities to generate either focused or “tophat” beams. As well as optical tests in the metrology lab, it is becoming increasingly important to optimise and characterise active optics under actual beamline operating conditions. Recently developed X-ray speckle-based at-wavelength metrology technique has shown great potential. The technique has been established and further developed at the Diamond Light Source and is increasingly being used to optimise active mirrors. Details of the X-ray speckle-based at-wavelength metrology technique and an example of its applicability in characterising and optimising a micro-focusing bimorph X-ray mirror are presented. Importantly, an unprecedented angular sensitivity in the range of two nanoradians for measuring the slope error of an optical surface has been demonstrated. Such a super precision metrology technique will be beneficial to the manufacturers of polished mirrors and also in optimization of beam shaping during experiments.

  5. Speckle-based at-wavelength metrology of X-ray mirrors with super accuracy

    International Nuclear Information System (INIS)

    Kashyap, Yogesh; Wang, Hongchang; Sawhney, Kawal

    2016-01-01

    X-ray active mirrors, such as bimorph and mechanically bendable mirrors, are increasingly being used on beamlines at modern synchrotron source facilities to generate either focused or “tophat” beams. As well as optical tests in the metrology lab, it is becoming increasingly important to optimise and characterise active optics under actual beamline operating conditions. Recently developed X-ray speckle-based at-wavelength metrology technique has shown great potential. The technique has been established and further developed at the Diamond Light Source and is increasingly being used to optimise active mirrors. Details of the X-ray speckle-based at-wavelength metrology technique and an example of its applicability in characterising and optimising a micro-focusing bimorph X-ray mirror are presented. Importantly, an unprecedented angular sensitivity in the range of two nanoradians for measuring the slope error of an optical surface has been demonstrated. Such a super precision metrology technique will be beneficial to the manufacturers of polished mirrors and also in optimization of beam shaping during experiments.

  6. Multi-Layer Organic Squaraine-Based Photodiode for Indirect X-Ray Detection

    Science.gov (United States)

    Iacchetti, Antonio; Binda, Maddalena; Natali, Dario; Giussani, Mattia; Beverina, Luca; Fiorini, Carlo; Peloso, Roberta; Sampietro, Marco

    2012-10-01

    The paper presents an organic-based photodiode coupled to a CsI(Tl) scintillator to realize an X-ray detector. A suitable blend of an indolic squaraine derivative and of fullerene derivative has been used for the photodiode, thus allowing external quantum efficiency in excess of 10% at a wavelength of 570 nm, well matching the scintillator output spectrum. Thanks to the additional deposition of a 15 nm thin layer of a suitable low electron affinity polymer, carriers injection from the metal into the organic semiconductor has been suppressed, and dark current density as low as has been obtained, which is comparable to standard Si-based photodiodes. By using a collimated X-ray beam impinging onto the scintillator mounted over the photodiode we have been able to measure current variations in the order of 150 pA on a dark current floor of less than 50 pA when operating the X-ray tube in switching mode, thus proving the feasibility of indirect X-ray detection by means of organic semiconductors.

  7. Capillary based Li-air batteries for in situ synchrotron X-ray powder diffraction studies

    DEFF Research Database (Denmark)

    Storm, Mie Møller; Johnsen, Rune E.; Younesi, Reza

    2015-01-01

    For Li-air batteries to reach their full potential as energy storage system, a complete understanding of the conditions and reactions in the battery during operation is needed. To follow the reactions in situ a capillary-based Li-O2 battery has been developed for synchrotron-based in situ X......-ray powder diffraction (XRPD). In this article, we present the results for the analysis of 1st and 2nd deep discharge and charge for a cathode being cycled between 2 and 4.6 V. The crystalline precipitation of Li2O2 only is observed in the capillary battery. However, there are indications of side reactions...... of constant exposure of X-ray radiation to the electrolyte and cathode during charge of the battery was also investigated. X-ray exposure during charge leads to changes in the development of the intensity and the FWHM of the Li2O2 diffraction peaks. The X-ray diffraction results are supported by ex situ X...

  8. Status of Kharkov X-Ray Generator Based on Compton Scattering NESTOR

    Energy Technology Data Exchange (ETDEWEB)

    Zelinsky, A.

    2005-04-11

    Nowadays the sources of the X-rays based on a storage ring with low beam energy and Compton scattering of intense laser beam are under development in several laboratories. In the paper the state-of-art in development and construction of cooperative project of a Kharkov advanced X-ray source NESTOR based on electron storage ring with beam energy 43-225 MeV and Nd:YAG laser is described. The layout of the facility is presented and latest results are described. The designed lattice includes 4 dipole magnets with combined focusing functions, 20 quadrupole magnets and 19 sextupoles with correcting components of magnetic field. At the present time a set of quadrupole magnet is under manufacturing and bending magnet reconstruction is going on. The main parameters of developed vacuum system providing residual gas pressure in the storage ring vacuum chamber up to 10{sup -9} torr are presented. The basic parameters of the X-ray source laser and injection systems are presented. The facility is going to be in operation in the middle of 2006 and generated X-rays flux is expected to be of about 10{sup 13} phot/s.

  9. Flexible X-ray detector based on sliced lead iodide crystal

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hui; Gao, Xiuying [College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu (China); Department of Materials Science, Sichuan University, Chengdu (China); Zhao, Beijun [Department of Materials Science, Sichuan University, Chengdu (China); Yang, Dingyu; Wangyang, Peihua; Zhu, Xinghua [College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu (China)

    2017-02-15

    A promising flexible X-ray detector based on inorganic semiconductor PbI{sub 2} crystal is reported. The sliced crystals mechanically cleaved from an as-grown PbI{sub 2} crystal act as the absorber directly converting the impinging X-ray photons to electron hole pairs. Due to the ductile feature of the PbI{sub 2} crystal, the detector can be operated under a highly curved state with the strain on the top surface up to 1.03% and still maintaining effective detection performance. The stable photocurrent and fast response were obtained with the detector repeated bending to a strain of 1.03% for 100 cycles. This work presents an approach for developing efficient and cost-effective PbI{sub 2}-based flexible X-ray detector. Photocurrent responses of the flexible PbI{sub 2} X-ray detector with the strain on the top surface up to 1.03% proposed in this work with the cross sectional structure and curved detector photograph as insets. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Development of multi-color scintillator based X-ray image intensifier

    International Nuclear Information System (INIS)

    Nittoh, Koichi; Konagai, Chikara; Noji, Takashi

    2004-01-01

    A multi-color scintillator based high-sensitive, wide dynamic range and long-life X-ray image intensifier has been developed. An europium activated Y 2 O 2 S scintillator, emitting red, green and blue photons of different intensities, is utilized as the output fluorescent screen of the intensifier. By combining this image intensifier with a suitably tuned high sensitive color CCD camera, it is possible for a sensitivity of the red color component to become six times higher than that of the conventional image intensifier. Simultaneous emission of a moderate green color and a weak blue color covers different sensitivity regions. This widens the dynamic range, by nearly two orders of ten. With this image intensifier, it is possible to image simultaneously complex objects containing various different X-ray transmission from paper, water or plastic to heavy metals. This high sensitivity intensifier, operated at lower X-ray exposure, causes less degradation of scintillator materials and less colorization of output screen glass, and thus helps achieve a longer lifetime. This color scintillator based image intensifier is being introduced for X-ray inspection in various fields

  11. Neural network Hilbert transform based filtered backprojection for fast inline x-ray inspection

    Science.gov (United States)

    Janssens, Eline; De Beenhouwer, Jan; Van Dael, Mattias; De Schryver, Thomas; Van Hoorebeke, Luc; Verboven, Pieter; Nicolai, Bart; Sijbers, Jan

    2018-03-01

    X-ray imaging is an important tool for quality control since it allows to inspect the interior of products in a non-destructive way. Conventional x-ray imaging, however, is slow and expensive. Inline x-ray inspection, on the other hand, can pave the way towards fast and individual quality control, provided that a sufficiently high throughput can be achieved at a minimal cost. To meet these criteria, an inline inspection acquisition geometry is proposed where the object moves and rotates on a conveyor belt while it passes a fixed source and detector. Moreover, for this acquisition geometry, a new neural-network-based reconstruction algorithm is introduced: the neural network Hilbert transform based filtered backprojection. The proposed algorithm is evaluated both on simulated and real inline x-ray data and has shown to generate high quality reconstructions of 400  ×  400 reconstruction pixels within 200 ms, thereby meeting the high throughput criteria.

  12. Near K-edge measurement of the X-ray attenuation coefficient of heavy elements using a tuneable X-ray source based on an electron LINAC

    CERN Document Server

    Materna, T; Mondelaers, W; Masschaele, B

    2000-01-01

    The X-ray attenuation coefficients of bismuth and of uranium were measured in the regions of 40-240 and 70-240 keV, respectively, using a tuneable hard X-ray source based on the linear electron accelerator at the University of Ghent. Results were compared with the semi-empirical values of Storm and Israel and to the theoretical values of Berger and Hubbell. We also propose a simple function for the attenuation coefficient in the vicinity of the K-edge for uranium and in an extended range of energy for bismuth. The set-up of the source at Ghent is described and the future improvements are explained.

  13. Cyclic olefin homopolymer-based microfluidics for protein crystallization and in situ X-ray diffraction

    International Nuclear Information System (INIS)

    Emamzadah, Soheila; Petty, Tom J.; De Almeida, Victor; Nishimura, Taisuke; Joly, Jacques; Ferrer, Jean-Luc; Halazonetis, Thanos D.

    2009-01-01

    A cyclic olefin homopolymer-based microfluidics system has been established for protein crystallization and in situ X-ray diffraction. Microfluidics is a promising technology for the rapid identification of protein crystallization conditions. However, most of the existing systems utilize silicone elastomers as the chip material which, despite its many benefits, is highly permeable to water vapour. This limits the time available for protein crystallization to less than a week. Here, the use of a cyclic olefin homopolymer-based microfluidics system for protein crystallization and in situ X-ray diffraction is described. Liquid handling in this system is performed in 2 mm thin transparent cards which contain 500 chambers, each with a volume of 320 nl. Microbatch, vapour-diffusion and free-interface diffusion protocols for protein crystallization were implemented and crystals were obtained of a number of proteins, including chicken lysozyme, bovine trypsin, a human p53 protein containing both the DNA-binding and oligomerization domains bound to DNA and a functionally important domain of Arabidopsis Morpheus’ molecule 1 (MOM1). The latter two polypeptides have not been crystallized previously. For X-ray diffraction analysis, either the cards were opened to allow mounting of the crystals on loops or the crystals were exposed to X-rays in situ. For lysozyme, an entire X-ray diffraction data set at 1.5 Å resolution was collected without removing the crystal from the card. Thus, cyclic olefin homopolymer-based microfluidics systems have the potential to further automate protein crystallization and structural genomics efforts

  14. Evaluation of stress gradient by x-ray stress measurement based on change in angle phi

    International Nuclear Information System (INIS)

    Sasaki, Toshihiko; Kuramoto, Makoto; Yoshioka, Yasuo.

    1985-01-01

    A new principle of X-ray stress evaluation for a sample with steep stress gradient has been prosed. The feature of this method is that the stress is determined by using so-called phi-method based on the change of phi-angle and thus has no effect on the penetration depth of X-rays. The procedure is as follows; firstly, an average stress within the penetration depth of X-rays is determined by changing only phi-angle under a fixed psi-angle, and then a distribution of the average stress vs. the penetration depth of X-rays is detected by repeating the similar procedure at different psi-angles. The following conclusions were found out as the result of residual stress measurements on a carbon steel of type S 55 C polished by emery paper. This method is practical enough to use for a plane stress problem. And the assumption of a linear stress gradient adopted in the authors' previous investigations is valid. In case of a triaxial stress analysis, this method is effective for the solution of three shearing stresses. However, three normal stresses can not be solved perfectly except particular psi-angles. (author)

  15. Study of Cr/Sc-based multilayer reflecting mirrors using soft x-ray reflectivity and standing wave-enhanced x-ray fluorescence

    Science.gov (United States)

    Wu, Meiyi; Burcklen, Catherine; André, Jean-Michel; Guen, Karine Le; Giglia, Angelo; Koshmak, Konstantin; Nannarone, Stefano; Bridou, Françoise; Meltchakov, Evgueni; Rossi, Sébastien de; Delmotte, Franck; Jonnard, Philippe

    2017-11-01

    We study Cr/Sc-based multilayer mirrors designed to work in the water window range using hard and soft x-ray reflectivity as well as x-ray fluorescence enhanced by standing waves. Samples differ by the elemental composition of the stack, the thickness of each layer, and the order of deposition. This paper mainly consists of two parts. In the first part, the optical performances of different Cr/Sc-based multilayers are reported, and in the second part, we extend further the characterization of the structural parameters of the multilayers, which can be extracted by comparing the experimental data with simulations. The methodology is detailed in the case of Cr/B4C/Sc sample for which a three-layer model is used. Structural parameters determined by fitting reflectivity curve are then introduced as fixed parameters to plot the x-ray standing wave curve, to compare with the experiment, and confirm the determined structure of the stack.

  16. Fast X-ray detection systems based on GaAs diodes grown by LPE

    International Nuclear Information System (INIS)

    Rente, C.; Lauter, J.; Apetz, R.; Lueth, H.

    1996-01-01

    We report on the fabrication and characterization of GaAs based X-ray detectors. The detector structures are grown by liquid phase epitaxy (LPE) and show typical background doping in the order of 10 14 cm -3 (n-type) so that active regions up to 43 μm could be realized. Schottky diodes were processed with active areas up to 1mm 2 . Typical dark current densities are as low as 360pA/mm 2 at 100V. The energy resolution of the detector in combination with a charge sensitive preamplifier was determined to be 1.6keV (FWHM) for x-rays with an energy between 6 and 60keV. The time response of the devices coupled to a fast transimpedance amplifier with a bandwidth of 100MHz was investigated. Single photon detection at room temperature was achieved for X-rays having energies of 14 keV and higher. The measured time resolutions were 600ps (FWHM=1.4ns) and 430ps (FWHM=1.0ns) for X-ray photons of 14.4keV and 21.5keV, respectively. The efficiency of the detector having a 43μm thick depleted layer was determined to be 70% at 14.4 keV and 40% at 21.5keV. These detectors open a new field of X-ray spectroscopy especially for high rate applications and timing measurements at synchrotron radiation facilities

  17. Fabrication of a Tantalum-Based Josephson Junction for an X-Ray Detector

    Science.gov (United States)

    Morohashi, Shin'ichi; Gotoh, Kohtaroh; Yokoyama, Naoki

    2000-06-01

    We have fabricated a tantalum-based Josephson junction for an X-ray detector. The tantalum layer was selected for the junction electrode because of its long quasiparticle lifetime, large X-ray absorption efficiency and stability against thermal cycling. We have developed a buffer layer to fabricate the tantalum layer with a body-centered cubic structure. Based on careful consideration of their superconductivity, we have selected a niobium thin layer as the buffer layer for fabricating the tantalum base electrode, and a tungsten thin layer for the tantalum counter electrode. Fabricated Nb/AlOx-Al/Ta/Nb and Nb/Ta/W/AlOx-Al/Ta/Nb Josephson junctions exhibited current-voltage characteristics with a low subgap leakage current.

  18. Pollen structure visualization using high-resolution laboratory-based hard X-ray tomography.

    Science.gov (United States)

    Li, Qiong; Gluch, Jürgen; Krüger, Peter; Gall, Martin; Neinhuis, Christoph; Zschech, Ehrenfried

    2016-10-14

    A laboratory-based X-ray microscope is used to investigate the 3D structure of unstained whole pollen grains. For the first time, high-resolution laboratory-based hard X-ray microscopy is applied to study pollen grains. Based on the efficient acquisition of statistically relevant information-rich images using Zernike phase contrast, both surface- and internal structures of pine pollen - including exine, intine and cellular structures - are clearly visualized. The specific volumes of these structures are calculated from the tomographic data. The systematic three-dimensional study of pollen grains provides morphological and structural information about taxonomic characters that are essential in palynology. Such studies have a direct impact on disciplines such as forestry, agriculture, horticulture, plant breeding and biodiversity. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. A wavelet-based Gaussian method for energy dispersive X-ray fluorescence spectrum

    Directory of Open Access Journals (Sweden)

    Pan Liu

    2017-05-01

    Full Text Available This paper presents a wavelet-based Gaussian method (WGM for the peak intensity estimation of energy dispersive X-ray fluorescence (EDXRF. The relationship between the parameters of Gaussian curve and the wavelet coefficients of Gaussian peak point is firstly established based on the Mexican hat wavelet. It is found that the Gaussian parameters can be accurately calculated by any two wavelet coefficients at the peak point which has to be known. This fact leads to a local Gaussian estimation method for spectral peaks, which estimates the Gaussian parameters based on the detail wavelet coefficients of Gaussian peak point. The proposed method is tested via simulated and measured spectra from an energy X-ray spectrometer, and compared with some existing methods. The results prove that the proposed method can directly estimate the peak intensity of EDXRF free from the background information, and also effectively distinguish overlap peaks in EDXRF spectrum.

  20. Design of high voltage power supply of miniature X-ray tube based on resonant Royer

    International Nuclear Information System (INIS)

    Liu Xiyao; Zeng Guoqiang; Tan Chengjun; Luo Qun; Gong Chunhui; Huang Rui

    2013-01-01

    Background: In recent years, X rays are widely used in various fields. With the rapid development of national economy, the demand of high quality, high reliability, and high stability miniature X-ray tube has grown rapidly. As an important core component of miniature X-ray tube, high voltage power supply has attracted wide attention. Purpose: To match miniature, the high voltage power supply should be small, lightweight, good quality, etc. Based on the basic performance requirements of existing micro-X-ray tube high voltage power supply, this paper designs an output from 0 to -30 kV adjustable miniature X-ray tube voltage DC power supply. Compared to half-bridge and full-bridge switching-mode power supply, its driving circuit is simple. With working on the linear condition, it has no switching noise. Methods: The main circuit makes use of DC power supply to provide the energy. The resonant Royer circuit supplies sine wave which drives to the high frequency transformer's primary winding with resultant sine-like high voltage appearing across the secondary winding. Then, the voltage doubling rectifying circuit would achieve further boost. In the regulator circuit, a feedback control resonant transistor base current is adopted. In order to insulate air, a silicone rubber is used for high pressure part packaging, and the output voltage is measured by the dividing voltage below -5 kV. Results: The stability of circuit is better than 0.2%/6 h and the percent of the output ripple voltage is less than 0.3%. Keeping the output voltage constant, the output current can reach 57 μA by changing the size of load resistor. This high voltage power supply based on resonant Royer can meet the requirement of miniature X-ray tube. Conclusions: The circuit can satisfy low noise, low ripple, low power and high voltage regulator power supply design. However, its efficiency is not high enough because of the linear condition. In the next design, to further reduce power consumption, we

  1. Examination of the gastrointestinal tract using the tussian X-ray contrast substance BAR-VIPS based on barium sulfate

    International Nuclear Information System (INIS)

    Ratobyl'skij, G.V.; Kaluzhskij, A.A.

    1997-01-01

    Results of X-ray studies of gastrointestinal tract using domestic X-ray contrast preparation based on barium sulfate BAR-VIPS developed by VIPS-MED company (t. Fryazino, Moscow region). Testing of the preparation has shown that BAR-VIPS permits to diagnose every pathological changes in esophagus, stomach, rectum, small intestine as well as to diagnose successfully large intestine diseases

  2. X-Ray Pulsar Profile Recovery Based on Tracking-Differentiator

    Directory of Open Access Journals (Sweden)

    Dapeng Zhang

    2016-01-01

    Full Text Available The profile recovery is an important work in X-ray pulsar-based navigation. It is a key step for the analysis on the pulsar signal’s characteristic and the computing of time of arrival (TOA. This paper makes an argument for an algorithm based on the tracking-differentiator (TD to recover the profile from the low Signal-to-Noise Ratio (SNR signals. In the method, a TD filter with cascade structure is designed which has very low phase delay and amplitude distortion. In the simulation experiment, two typical pulsars (PSR B0531+21 and PSR B1937+21 are used to verify the algorithm’s performance. The simulation results show that the method satisfies the application requirements in the aspects of SNR and profile fidelity. By processing the data collected by the Rossi X-Ray Timing Explorer (RXTE satellite in space, similar results can also be achieved.

  3. LabVIEW-based X-ray detection system for laser compton scattering experiment

    International Nuclear Information System (INIS)

    Luo Wen; Xu Wang; Pan Qiangyan

    2010-01-01

    A LabVIEW-based X-ray detection system has been developed for laser-Compton scattering (LCS) experiment at the 100 MeV Linac of the Shanghai Institute of Applied Physics (SINAP). It mainly consists of a Si (Li) detector, readout electronics and a LabVIEW-based Data Acquisition (DAQ), and possesses the functions of signal spectrum displaying, acquisition control and simple online data analysis and so on. The performance test shows that energy and time resolutions of the system are 184 eV at 5.9 keV and ≤ 1% respectively and system instability is found to be 0.3‰ within a week. As a result, this X-ray detection system has low-cost and high-performance features and can meet the requirements of LCS experiment. (authors)

  4. Taheri-Saramad x-ray detector (TSXD): a novel high spatial resolution x-ray imager based on ZnO nano scintillator wires in polycarbonate membrane.

    Science.gov (United States)

    Taheri, A; Saramad, S; Ghalenoei, S; Setayeshi, S

    2014-01-01

    A novel x-ray imager based on ZnO nanowires is designed and fabricated. The proposed architecture is based on scintillation properties of ZnO nanostructures in a polycarbonate track-etched membrane. Because of higher refractive index of ZnO nanowire compared to the membrane, the nanowire acts as an optical fiber that prevents the generated optical photons to spread inside the detector. This effect improves the spatial resolution of the imager. The detection quantum efficiency and spatial resolution of the fabricated imager are 11% and <6.8 μm, respectively.

  5. Taheri-Saramad x-ray detector (TSXD): A novel high spatial resolution x-ray imager based on ZnO nano scintillator wires in polycarbonate membrane

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, A., E-mail: at1361@aut.ac.ir; Saramad, S.; Ghalenoei, S.; Setayeshi, S. [Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran 15875-4413 (Iran, Islamic Republic of)

    2014-01-15

    A novel x-ray imager based on ZnO nanowires is designed and fabricated. The proposed architecture is based on scintillation properties of ZnO nanostructures in a polycarbonate track-etched membrane. Because of higher refractive index of ZnO nanowire compared to the membrane, the nanowire acts as an optical fiber that prevents the generated optical photons to spread inside the detector. This effect improves the spatial resolution of the imager. The detection quantum efficiency and spatial resolution of the fabricated imager are 11% and <6.8 μm, respectively.

  6. Three Dimensional Digital Sieving of Asphalt Mixture Based on X-ray Computed Tomography

    OpenAIRE

    Chichun Hu; Jiexian Ma; M. Emin Kutay

    2017-01-01

    In order to perform three-dimensional digital sieving based on X-ray computed tomography images, the definition of digital sieve size (DSS) was proposed, which was defined as the minimum length of the minimum bounding squares of all possible orthographic projections of an aggregate. The corresponding program was developed to reconstruct aggregate structure and to obtain DSS. Laboratory experiments consisting of epoxy-filled aggregate specimens were conducted to investigate the difference betw...

  7. Synthesis, X-ray crystallography, spectroscopy, electrochemistry, thermal and kinetic study of uranyl Schiff base complexes

    Czech Academy of Sciences Publication Activity Database

    Asadi, Z.; Golzard, F.; Eigner, Václav; Dušek, Michal

    2013-01-01

    Roč. 66, č. 20 (2013), s. 3629-3646 ISSN 0095-8972 R&D Projects: GA ČR(CZ) GAP204/11/0809 Institutional support: RVO:68378271 Keywords : X-ray crystallography * uranyl Schiff base complex * kinetics of thermal decomposition * cyclic voltammetry * kinetics and mechanism Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.224, year: 2013

  8. Sensitivity of photon-counting based K-edge imaging in X-ray computed tomography.

    Science.gov (United States)

    Roessl, Ewald; Brendel, Bernhard; Engel, Klaus-Jürgen; Schlomka, Jens-Peter; Thran, Axel; Proksa, Roland

    2011-09-01

    The feasibility of K-edge imaging using energy-resolved, photon-counting transmission measurements in X-ray computed tomography (CT) has been demonstrated by simulations and experiments. The method is based on probing the discontinuities of the attenuation coefficient of heavy elements above and below the K-edge energy by using energy-sensitive, photon counting X-ray detectors. In this paper, we investigate the dependence of the sensitivity of K-edge imaging on the atomic number Z of the contrast material, on the object diameter D , on the spectral response of the X-ray detector and on the X-ray tube voltage. We assume a photon-counting detector equipped with six adjustable energy thresholds. Physical effects leading to a degradation of the energy resolution of the detector are taken into account using the concept of a spectral response function R(E,U) for which we assume four different models. As a validation of our analytical considerations and in order to investigate the influence of elliptically shaped phantoms, we provide CT simulations of an anthropomorphic Forbild-Abdomen phantom containing a gold-contrast agent. The dependence on the values of the energy thresholds is taken into account by optimizing the achievable signal-to-noise ratios (SNR) with respect to the threshold values. We find that for a given X-ray spectrum and object size the SNR in the heavy element's basis material image peaks for a certain atomic number Z. The dependence of the SNR in the high- Z basis-material image on the object diameter is the natural, exponential decrease with particularly deteriorating effects in the case where the attenuation from the object itself causes a total signal loss below the K-edge. The influence of the energy-response of the detector is very important. We observed that the optimal SNR values obtained with an ideal detector and with a CdTe pixel detector whose response, showing significant tailing, has been determined at a synchrotron differ by factors of

  9. Contribute to quantitative identification of casting defects based on computer analysis of X-ray images

    Directory of Open Access Journals (Sweden)

    Z. Ignaszak

    2007-12-01

    Full Text Available The forecast of structure and properties of casting is based on results of computer simulation of physical processes which are carried out during the casting processes. For the effective using of simulation system it is necessary to validate mathematica-physical models describing process of casting formation and the creation of local discontinues, witch determinate the casting properties.In the paper the proposition for quantitative validation of VP system using solidification casting defects by information sources of II group (methods of NDT was introduced. It was named the VP/RT validation (virtual prototyping/radiographic testing validation. Nowadays identification of casting defects noticeable on X-ray images bases on comparison of X-ray image of casting with relates to the ASTM. The results of this comparison are often not conclusive because based on operator’s subjective assessment. In the paper the system of quantitative identification of iron casting defects on X-ray images and classification this defects to ASTM class is presented. The methods of pattern recognition and machine learning were applied.

  10. High-energy x-ray grating-based phase-contrast radiography of human anatomy

    Science.gov (United States)

    Horn, Florian; Hauke, Christian; Lachner, Sebastian; Ludwig, Veronika; Pelzer, Georg; Rieger, Jens; Schuster, Max; Seifert, Maria; Wandner, Johannes; Wolf, Andreas; Michel, Thilo; Anton, Gisela

    2016-03-01

    X-ray grating-based phase-contrast Talbot-Lau interferometry is a promising imaging technology that has the potential to raise soft tissue contrast in comparison to conventional attenuation-based imaging. Additionally, it is sensitive to attenuation, refraction and scattering of the radiation and thus provides complementary and otherwise inaccessible information due to the dark-field image, which shows the sub-pixel size granularity of the measured object. Until recent progress the method has been mainly limited to photon energies below 40 keV. Scaling the method to photon energies that are sufficient to pass large and spacious objects represents a challenging task. This is caused by increasing demands regarding the fabrication process of the gratings and the broad spectra that come along with the use of polychromatic X-ray sources operated at high acceleration voltages. We designed a setup that is capable to reach high visibilities in the range from 50 to 120 kV. Therefore, spacious and dense parts of the human body with high attenuation can be measured, such as a human knee. The authors will show investigations on the resulting attenuation, differential phase-contrast and dark-field images. The images experimentally show that X-ray grating-based phase-contrast radiography is feasible with highly absorbing parts of the human body containing massive bones.

  11. Development of Ta-based Superconducting Tunnel Junction X-ray Detectors for Fluorescence XAS

    International Nuclear Information System (INIS)

    Friedrich, S.; Drury, O.; Hall, J.; Cantor, R.

    2009-01-01

    We are developing superconducting tunnel junction (STJ) soft X-ray detectors for chemical analysis of dilute samples by fluorescence-detected X-ray absorption spectroscopy (XAS). Our 36-pixel Nb-based STJ spectrometer covers a solid angle (Omega)/4π ∼ 10 -3 , offers an energy resolution of ∼10-20 eV FWHM for energies up to ∼1 keV, and can be operated at total count rates of ∼10 6 counts/s. For increased quantum efficiency and cleaner response function, we have now started the development of Ta-based STJ detector arrays. Initial devices modeled after our Nb-based STJs have an energy resolution below 10 eV FWHM for X-ray energies below 1 keV, and pulse rise time discrimination can be used to improve their response function for energies up to several keV. We discuss the performance of the Ta-STJs and outline steps towards the next-generation of large STJ detector arrays with higher sensitivity.

  12. New imaging technique based on diffraction of a focused x-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Kazimirov, A [Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States); Kohn, V G [Russian Research Center ' Kurchatov Institute, 123182 Moscow (Russian Federation); Cai, Z-H [Advanced Photon Source, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)], E-mail: ayk7@cornell.edu

    2009-01-07

    We present first experimental results from a new diffraction depth-sensitive imaging technique. It is based on the diffraction of a focused x-ray beam from a crystalline sample and recording the intensity pattern on a high-resolution CCD detector positioned at a focal plane. Structural non-uniformity inside the sample results in a region of enhanced intensity in the diffraction pattern. The technique was applied to study silicon-on-insulator thin layers of various thicknesses which revealed a complex strain profile within the layers. A circular Fresnel zone plate was used as a focusing optic. Incoherent diffuse scattering spreads out of the diffraction plane and results in intensity recorded outside of the focal spot providing a new approach to separately register x-rays scattered coherently and incoherently from the sample. (fast track communication)

  13. High resolution monochromatic X-ray imaging system based on spherically bent crystals

    International Nuclear Information System (INIS)

    Aglitskiy, Y.; Lehecka, T.; Obenschain, S.; Bodner, S.; Pawley, C.; Gerber, K.; Sethian, J.; Brown, C.M.; Seely, J.; Feldman, U.; Holland, G.

    1997-01-01

    We have developed a new X-ray imaging system based on spherically curved crystals. It is designed and used for diagnostics of targets ablatively accelerated by the Nike KrF laser [1,2]. The imaging system is used for plasma diagnostics of the main target and for characterization of potential backlighters. A spherically curved quartz crystal (2d=6.687 Angstrom, R=200mm) is used to produce monochromatic backlit images with the He-like Si resonance line (1865 eV) as the source of radiation. The spatial resolution of the X-ray optical system is 3 endash 4 μm. Time resolved backlit monochromatic images of CH planar targets driven by the Nike facility have been obtained with 6 endash 7 μm spatial resolution. copyright 1997 American Institute of Physics

  14. High resolution monochromatic X-ray imaging system based on spherically bent crystals

    International Nuclear Information System (INIS)

    Aglitskiy, Y.; Lehecka, T.; Obenschain, S.; Bodner, S.; Pawley, C.; Gerber, K.; Sethian, J.; Brown, C. M.; Seely, J.; Feldman, U.; Holland, G.

    1997-01-01

    We have developed a new X-ray imaging system based on spherically curved crystals. It is designed and used for diagnostics of targets ablatively accelerated by the Nike KrF laser. The imaging system is used for plasma diagnostics of the main target and for characterization of potential backlighters. A spherically curved quartz crystal (2d=6.687 A, R=200 mm) is used to produce monochromatic backlit images with the He-like Si resonance line (1865 eV) as the source of radiation. The spatial resolution of the X-ray optical system is 3-4 μm. Time resolved backlit monochromatic images of CH planar targets driven by the Nike facility have been obtained with 6-7 μm spatial resolution

  15. High-resolution monochromatic x-ray imaging system based on spherically bent crystals

    International Nuclear Information System (INIS)

    Aglitskiy, Y.; Lehecka, T.; Obenschain, S.; Bodner, S.; Pawley, C.; Gerber, K.; Sethian, J.; Brown, C.M.; Seely, J.; Feldman, U.; Holland, G.

    1998-01-01

    We have developed an improved x-ray imaging system based on spherically curve crystals. It is designed and used for diagnostics of targets ablatively accelerated by the Nike KrF laser. A spherically curved quartz crystal (2d=6.687 Angstrom, R=200 mm) has been used to produce monochromatic backlit images with the He-like Si resonance line (1865 eV) as the source of radiation. The spatial resolution of the x-ray optical system is 1.7 μm in selected places and 2 - 3 μm over a larger area. Time-resolved backlit monochromatic images of polystyrene planar targets driven by the Nike facility have been obtained with a spatial resolution of 2.5 μm in selected places and 5 μm over the focal spot of the Nike laser. copyright 1998 Optical Society of America

  16. An InGrid based Low Energy X-ray Detector

    CERN Document Server

    Krieger, Christoph; Kaminski, Jochen; Lupberger, Michael; Vafeiadis, Theodoros

    2014-01-01

    An X-ray detector based on the combination of an integrated Micromegas stage with a pixel chip has been built in order to be installed at the CERN Axion Solar Telescope. Due to its high granularity and spatial resolution this detector allows for a topological background suppression along with a detection threshold below $1\\,\\text{keV}$. Tests at the CAST Detector Lab show the detector's ability to detect X-ray photons down to an energy as low as $277\\,\\text{eV}$. The first background data taken after the installation at the CAST experiment underline the detector's performance with an average background rate of $5\\times10^{-5}\\,/\\text{keV}/\\text{cm}^2/\\text{s}$ between 2 and $10\\,\\text{keV}$ when using a lead shielding.

  17. Method and apparatus for digitally based high speed x-ray spectrometer

    International Nuclear Information System (INIS)

    Warburton, W.K.; Hubbard, B.

    1997-01-01

    A high speed, digitally based, signal processing system which accepts input data from a detector-preamplifier and produces a spectral analysis of the x-rays illuminating the detector. The system achieves high throughputs at low cost by dividing the required digital processing steps between a ''hardwired'' processor implemented in combinatorial digital logic, which detects the presence of the x-ray signals in the digitized data stream and extracts filtered estimates of their amplitudes, and a programmable digital signal processing computer, which refines the filtered amplitude estimates and bins them to produce the desired spectral analysis. One set of algorithms allow this hybrid system to match the resolution of analog systems while operating at much higher data rates. A second set of algorithms implemented in the processor allow the system to be self calibrating as well. The same processor also handles the interface to an external control computer. 19 figs

  18. [Research on increasing X-ray protection capability based on photonic crystal technology].

    Science.gov (United States)

    Li, Ping; Zhao, Peng; Zhang, Rui

    2014-06-01

    Light cannot be propagated within the range of photonic crystal band gaps. Based on this unique property, we proposed a method to improve anti-radiation capability through one-dimensional photonic crystal coating. Using transmission matrix method, we determined the appropriate dielectric materials, thickness and periodic numbers of photonic crystals through Matlab programming simulation. Then, compound one-dimensional photonic crystal coating was designed which was of high anti-radiation rate within the range of X-ray. As is shown through simulation experiments, the reflection rate against X-ray was higher than 90 percent, and the desired anti-radiation effect was achieved. Thus, this method is able to help solve the technical problems facing the inorganic lead glass such as thickness, weightiness, costliness, high lead equivalent, low transparency and high cost. This method has won China's national invention patent approval, and the patent number is 201220228549.2.

  19. Extending synchrotron-based atomic physics experiments into the hard X-ray region

    International Nuclear Information System (INIS)

    LeBrun, T.

    1996-01-01

    The high-brightness, hard x-ray beams available from third-generation synchrotron sources are opening new opportunities to study the deepest inner shells of atoms, an area where little work has been done and phenomena not observed in less tightly bound inner-shells are manifested. In addition scattering processes which are weak at lower energies become important, providing another tool to investigate atomic structure as well as an opportunity to study photon/atom interactions beyond photoabsorption. In this contribution the authors discuss some of the issues related to extending synchrotron-based atomic physics experiments into the hard x-ray region from the physical and the experimental point of view. They close with a discussion of a technique, resonant Raman scattering, that may prove invaluable in determining the spectra of the very highly-excited states resulting from the excitation of deep inner shells

  20. Discriminating cosmic muons and X-rays based on rise time using a GEM detector

    Science.gov (United States)

    Wu, Hui-Yin; Zhao, Sheng-Ying; Wang, Xiao-Dong; Zhang, Xian-Ming; Qi, Hui-Rong; Zhang, Wei; Wu, Ke-Yan; Hu, Bi-Tao; Zhang, Yi

    2016-08-01

    Gas electron multiplier (GEM) detectors have been used in cosmic muon scattering tomography and neutron imaging over the last decade. In this work, a triple GEM device with an effective readout area of 10 cm × 10 cm is developed, and a method of discriminating between cosmic muons and X-rays based on rise time is tested. The energy resolution of the GEM detector is tested by 55Fe ray source to prove the GEM detector has a good performance. Analysis of the complete signal-cycles allows us to get the rise time and pulse heights. The experiment result indicates that cosmic muons and X-rays can be discriminated with an appropriate rise time threshold. Supported by National Natural Science Foundation of China (11135002, 11275235, 11405077, 11575073)

  1. A lab-based ambient pressure x-ray photoelectron spectrometer with exchangeable analysis chambers

    Energy Technology Data Exchange (ETDEWEB)

    Newberg, John T., E-mail: jnewberg@udel.edu; Arble, Chris; Goodwin, Chris; Khalifa, Yehia; Broderick, Alicia [Department of Chemistry & Biochemistry, University of Delaware, Newark, Delaware 19716 (United States); Åhlund, John [Scienta AB, Box 15120, 750 15 Uppsala (Sweden)

    2015-08-15

    Ambient pressure X-ray photoelectron spectroscopy (APXPS) is a powerful spectroscopy tool that is inherently surface sensitive, elemental, and chemical specific, with the ability to probe sample surfaces under Torr level pressures. Herein, we describe the design of a new lab-based APXPS system with the ability to swap small volume analysis chambers. Ag 3d(5/2) analyses of a silver foil were carried out at room temperature to determine the optimal sample-to-aperture distance, x-ray photoelectron spectroscopy analysis spot size, relative peak intensities, and peak full width at half maximum of three different electrostatic lens modes: acceleration, transmission, and angular. Ag 3d(5/2) peak areas, differential pumping pressures, and pump performance were assessed under varying N{sub 2}(g) analysis chamber pressures up to 20 Torr. The commissioning of this instrument allows for the investigation of molecular level interfacial processes under ambient vapor conditions in energy and environmental research.

  2. Simulation of single grid-based phase-contrast x-ray imaging (g-PCXI)

    Energy Technology Data Exchange (ETDEWEB)

    Lim, H.W.; Lee, H.W. [Department of Radiation Convergence Engineering, iTOMO Group, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 26493 (Korea, Republic of); Cho, H.S., E-mail: hscho1@yonsei.ac.kr [Department of Radiation Convergence Engineering, iTOMO Group, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 26493 (Korea, Republic of); Je, U.K.; Park, C.K.; Kim, K.S.; Kim, G.A.; Park, S.Y.; Lee, D.Y.; Park, Y.O.; Woo, T.H. [Department of Radiation Convergence Engineering, iTOMO Group, Yonsei University, 1 Yonseidae-gil, Wonju, Gangwon-do 26493 (Korea, Republic of); Lee, S.H.; Chung, W.H.; Kim, J.W.; Kim, J.G. [R& D Center, JPI Healthcare Co., Ltd., Ansan 425-833 (Korea, Republic of)

    2017-04-01

    Single grid-based phase-contrast x-ray imaging (g-PCXI) technique, which was recently proposed by Wen et al. to retrieve absorption, scattering, and phase-gradient images from the raw image of the examined object, seems a practical method for phase-contrast imaging with great simplicity and minimal requirements on the setup alignment. In this work, we developed a useful simulation platform for g-PCXI and performed a simulation to demonstrate its viability. We also established a table-top setup for g-PCXI which consists of a focused-linear grid (200-lines/in strip density), an x-ray tube (100-μm focal spot size), and a flat-panel detector (48-μm pixel size) and performed a preliminary experiment with some samples to show the performance of the simulation platform. We successfully obtained phase-contrast x-ray images of much enhanced contrast from both the simulation and experiment and the simulated contract seemed similar to the experimental contrast, which shows the performance of the developed simulation platform. We expect that the simulation platform will be useful for designing an optimal g-PCXI system. - Highlights: • It is proposed for the single grid-based phase-contrast x-ray imaging (g-PCXI) technique. • We implemented for a numerical simulation code. • The preliminary experiment with several samples to compare is performed. • It is expected to be useful to design an optimal g-PCXI system.

  3. A study on characteristics of X-ray detector for CCD-based EPID

    International Nuclear Information System (INIS)

    Chung, Yong Hyun

    1999-02-01

    The combination of the metal plate/phosphor screen as a x-ray detector with a CCD camera is the most popular detector system among various electronic portal imaging devices (EPIDs). There is a need to optimize the thickness of the metal plate/phosphor screen with high detection efficiency and high spatial resolution for effective transferring of anatomical information. In this study, the thickness dependency on the detection efficiency and the spatial resolution of the metal plate/phosphor screen was investigated by calculation and measurement. The result can be used to determine the optimal thickness of the metal plate as well as of the phosphor screen for the x-ray detector design of therapeutic x-ray imaging and for any specific application. Bremsstrahlung spectrum was calculated by Monte Carlo simulation and by Schiff formula. The detection efficiency was calculated from the total absorbed energy in the phosphor screen using the Monte Carlo simulation and the light output was measured. The spatial resolution, which was defined from the spatial distribution of the absorbed energy, was also calculated and the edge spread function was measured. It was found that the detection efficiency and the spatial resolution were mainly determined by the thickness of metal plate and phosphor screen, respectively. It was also revealed that the detection efficiency and the spatial resolution have trade-off in term of the thickness of the phosphor screen. As the phosphor thickness increases, the detection efficiency increases but the spatial resolution decreases. The curve illustrating the trade-off between the detection efficiency and the spatial resolution of the metal plate/phosphor screen detector is obtained as a function of the phosphor thickness. Based on the calculations, prototype CCD-based EPID was developed and then tested by acquiring phantom images for 6 MV x-ray beam. While, among the captured images, each frame suffered from quantum noise, the frame averaging

  4. Design of a microcomputer-based X-ray diffractometer controller

    International Nuclear Information System (INIS)

    Naval, P.C. Jr.

    1988-01-01

    This work describes the design of an Apple II-based X-ray diffractometer controller capable of acquiring and analyzing X-ray powder diffraction data. The controller's interrupt-drivers hardware includes an on-based scaler for counting X-ray pulses, a closed-loop stepper motor driver for Philips PW 1050 Vertical Goniometer, and circuits for present data collection and safety. ACQUIRE - data acquisition program for the controller coordinates its various devices so that it can perform sample scanning in any of the following modes: continuous, present tome or present count scanning. This program watches over the scanning process and will try to correct any error it detects. Any fault monitored is logged on disk. The collected diffraction data are stored on disk together with its data acquisition parameters and may be transported to another computer. Data analysis is done by ANALYZE a program that operates on the output file generated by ACQUIRE. Its 15 single-keystroke commands permit panning and zooming of the sample's diffractogram, data smoothing, data peak search, peak report generation, and digital plotting. Data smoothing uses a third-degree Savitzky-Golay Convoluting Filter of user defined width. For peak detection, the peak search algorithm examines the diffractograms second derivative for any Gaussian resemblance and checks the peaks' area for statistical significance. The hard copy plot is available from any on-line digital plotted supporting EPSON's Mode D Plotter Commands. (Author). 15 refs. Appendixes p. 85-163

  5. Grating-based X-ray Dark-field Computed Tomography of Living Mice.

    Science.gov (United States)

    Velroyen, A; Yaroshenko, A; Hahn, D; Fehringer, A; Tapfer, A; Müller, M; Noël, P B; Pauwels, B; Sasov, A; Yildirim, A Ö; Eickelberg, O; Hellbach, K; Auweter, S D; Meinel, F G; Reiser, M F; Bech, M; Pfeiffer, F

    2015-10-01

    Changes in x-ray attenuating tissue caused by lung disorders like emphysema or fibrosis are subtle and thus only resolved by high-resolution computed tomography (CT). The structural reorganization, however, is of strong influence for lung function. Dark-field CT (DFCT), based on small-angle scattering of x-rays, reveals such structural changes even at resolutions coarser than the pulmonary network and thus provides access to their anatomical distribution. In this proof-of-concept study we present x-ray in vivo DFCTs of lungs of a healthy, an emphysematous and a fibrotic mouse. The tomographies show excellent depiction of the distribution of structural - and thus indirectly functional - changes in lung parenchyma, on single-modality slices in dark field as well as on multimodal fusion images. Therefore, we anticipate numerous applications of DFCT in diagnostic lung imaging. We introduce a scatter-based Hounsfield Unit (sHU) scale to facilitate comparability of scans. In this newly defined sHU scale, the pathophysiological changes by emphysema and fibrosis cause a shift towards lower numbers, compared to healthy lung tissue.

  6. Classification of glutinous rice (Oryza sativa L.) starches based on X-ray diffraction pattern

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Q.; Abe, T.; Ando, H.; Sasahara, T.

    1993-07-01

    This study was carried out to analyse the cultivar variability of the X-ray diffraction pattern of glutinous rice starches. Four peaks in the X-ray diffractograms were identified, i.e. 3b, 4a, 4b and 6a. The four peaks were measured from the base line for 71 cultivars and three M{sub 3} lines which were irradiated by γ-rays at the rates of 10, 20 and 30 kr, respectively. Glutinous rice starches were classified into two types by discriminant analysis based on the values of 3b/4b, 4a/4b and 6a/4b. The X-ray diffraction type of the three cultivars did not change with the cultivation areas of different latitude, while that of eleven cultivars varied. Degree of crystallinity was estimated using the formula, (I{sub max} — I{sub i})/I{sub max} where I{sub max} is the maximum height from background intensity line among cultivars, and I{sub i} represents the four peaks. These ratios indicated that the changes in the order of crystallinity were similar to those with the water content and/or hydration and temperature for gelatinization among and/or within cultivars. (author)

  7. Elemental and mineralogical study of earth-based pigments using particle induced X-ray emission and X-ray diffraction

    International Nuclear Information System (INIS)

    Nel, P.; Lynch, P.A.; Laird, J.S.; Casey, H.M.; Goodall, L.J.; Ryan, C.G.; Sloggett, R.J.

    2010-01-01

    Artwork and precious artefacts demand non-destructive analytical methodologies for art authentication, attribution and provenance assessment. However, structural and chemical characterisation represents a challenging problem with existing analytical techniques. A recent authentication case based on an Australian Aboriginal artwork, indicate there is substantial benefit in the ability of particle induced X-ray emission (PIXE), coupled with dynamic analysis (DA) to characterise pigments through trace element analysis. However, this information alone is insufficient for characterising the mineralogical residence of trace elements. For this reason a combined methodology based on PIXE and X-ray diffraction (XRD) has been performed to explore the benefits of a more comprehensive data set. Many Aboriginal paintings and artefacts are predominantly earth pigment based. This makes these cultural heritage materials an ideal case study for testing the above combined methodological approach on earth-based pigments. Samples of synthetic and naturally occurring earth-based pigments were obtained from a range of sources, which include Indigenous communities within Australia's Kimberley region. PIXE analyses using a 3 MeV focussed proton beam at the CSIRO nuclear microprobe, as well as laboratory-based XRD was carried out on the above samples. Elemental signature spectra as well as mineralogical data were used to assess issues regarding synthetic and naturally occurring earth pigments with the ultimate aim of establishing provenance.

  8. Soft X-ray imaging of thick carbon-based materials using the normal incidence multilayer optics.

    Science.gov (United States)

    Artyukov, I A; Feschenko, R M; Vinogradov, A V; Bugayev, Ye A; Devizenko, O Y; Kondratenko, V V; Kasyanov, Yu S; Hatano, T; Yamamoto, M; Saveliev, S V

    2010-10-01

    The high transparency of carbon-containing materials in the spectral region of "carbon window" (lambda approximately 4.5-5nm) introduces new opportunities for various soft X-ray microscopy applications. The development of efficient multilayer coated X-ray optics operating at the wavelengths of about 4.5nm has stimulated a series of our imaging experiments to study thick biological and synthetic objects. Our experimental set-up consisted of a laser plasma X-ray source generated with the 2nd harmonics of Nd-glass laser, scandium-based thin-film filters, Co/C multilayer mirror and X-ray film UF-4. All soft X-ray images were produced with a single nanosecond exposure and demonstrated appropriate absorption contrast and detector-limited spatial resolution. A special attention was paid to the 3D imaging of thick low-density foam materials to be used in design of laser fusion targets.

  9. Operation of an InGrid based X-ray detector at the CAST experiment

    Science.gov (United States)

    Krieger, Christoph; Desch, Klaus; Kaminski, Jochen; Lupberger, Michael

    2018-02-01

    The CERN Axion Solar Telescope (CAST) is searching for axions and other particles which could be candidates for DarkMatter and even Dark Energy. These particles could be produced in the Sun and detected by a conversion into soft X-ray photons inside a strong magnetic field. In order to increase the sensitivity for physics beyond the Standard Model, detectors with a threshold below 1 keV as well as efficient background rejection methods are required to compensate for low energies and weak couplings resulting in very low detection rates. Those criteria are fulfilled by a detector utilizing the combination of a pixelized readout chip with an integrated Micromegas stage. These InGrid (Integrated Grid) devices can be build by photolithographic postprocessing techniques, resulting in a close to perfect match of grid and pixels facilitating the detection of single electrons on the chip surface. The high spatial resolution allows for energy determination by simple electron counting as well as for an event-shape based analysis as background rejection method. Tests at an X-ray generator revealed the energy threshold of an InGrid based X-ray detector to be well below the carbon Kα line at 277 eV. After the successful demonstration of the detectors key features, the detector was mounted at one of CAST's four detector stations behind an X-ray telescope in 2014. After several months of successful operation without any detector related interruptions, the InGrid based X-ray detector continues data taking at CAST in 2015. During operation at the experiment, background rates in the order of 10-5 keV-1 cm-2 s-1 have been achieved by application of a likelihood based method discriminating the non-photon background originating mostly from cosmic rays. For continued operation in 2016, an upgraded InGrid based detector is to be installed among other improvements including decoupling and sampling of the signal induced on the grid as well as a veto scintillator to further lower the

  10. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    International Nuclear Information System (INIS)

    Zhou, Wei; Majidi, Keivan; Brankov, Jovan G.

    2014-01-01

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα 1 line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample

  11. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    Science.gov (United States)

    Zhou, Wei; Majidi, Keivan; Brankov, Jovan G.

    2014-08-01

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα1 line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample.

  12. Analyzer-based phase-contrast imaging system using a micro focus x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wei [BME Department, Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Majidi, Keivan; Brankov, Jovan G., E-mail: brankov@iit.edu [ECE Department, Illinois Institute of Technology, Chicago, Illinois 60616 (United States)

    2014-08-15

    Here we describe a new in-laboratory analyzer based phase contrast-imaging (ABI) instrument using a conventional X-ray tube source (CXS) aimed at bio-medical imaging applications. Phase contrast-imaging allows visualization of soft tissue details usually obscured in conventional X-ray imaging. The ABI system design and major features are described in detail. The key advantage of the presented system, over the few existing CXS ABI systems, is that it does not require high precision components, i.e., CXS, X-ray detector, and electro-mechanical components. To overcome a main problem introduced by these components, identified as temperature stability, the system components are kept at a constant temperature inside of three enclosures, thus minimizing the electrical and mechanical thermal drifts. This is achieved by using thermoelectric (Peltier) cooling/heating modules that are easy to control precisely. For CXS we utilized a microfocus X-ray source with tungsten (W) anode material. In addition the proposed system eliminates tungsten's multiple spectral lines by selecting monochromator crystal size appropriately therefore eliminating need for the costly mismatched, two-crystal monochromator. The system imaging was fine-tuned for tungsten Kα{sub 1} line with the energy of 59.3 keV since it has been shown to be of great clinical significance by a number of researchers at synchrotron facilities. In this way a laboratory system that can be used for evaluating and quantifying tissue properties, initially explored at synchrotron facilities, would be of great interest to a larger research community. To demonstrate the imaging capability of our instrument we use a chicken thigh tissue sample.

  13. Combined use of infrared and hard X-ray microprobes for spectroscopy-based neuroanatomy

    Science.gov (United States)

    Surowka, A. D.; Ziomber, A.; Czyzycki, M.; Migliori, A.; Pieklo, L.; Kasper, K.; Szczerbowska-Boruchowska, M.

    2018-05-01

    Understanding the pathological triggers that affect the structural and physiological integrity of biochemical milieu of neurons is crucial to extend our knowledge on brain disorders, that are in many circumstances hardly treatable. Over recently, by using sophisticated hyperspectral micro-imaging modalities, it has been placed within our reach to get an insight into high fidelity histological details along with corresponding biochemical information in a label-free fashion, without using any additional chemical fixatives. However, in order to push forwards extensive application of these methods in the clinical arena, it is viable to make further iterations in novel data analysis protocols in order to boost their sensitivity. Therefore, in our study we proposed a new combined approach utilizing both benchtop Fourier transform infrared (FTIR) and synchrotron X-ray fluorescence (SR-XRF) micro-spectroscopies coupled with multivariate data clustering using the K-means algorithm for combined molecular and elemental micro-imaging, so that these complimentary analytical tools could be used for delineating between various brain structures based on their biochemical composition. By utilizing mid-IR transmission FTIR experiments, the biochemical composition in terms of lipids, proteins and phosphodiesters became accessible. In turn, the SR-XRF experiment was carried out at the advanced IAEA X-ray spectrometry station at Elettra Sincrotrone Trieste. By measuring in vacuum and by using the primary exciting X-ray beam, monochromatized to 10.5 keV, we took advantage of accessing the characteristic X-ray lines of a variety of elements ranging from carbon to zinc. Herein, we can report that the developed methodology has high specificity for label-free discriminating between lipid- and protein-rich brain tissue areas.

  14. Nanosecond X-ray detector based on high resistivity ZnO single crystal semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xiaolong; He, Yongning, E-mail: yongning@mail.xjtu.edu.cn; Peng, Wenbo; Huang, Zhiyong; Qi, Xiaomeng; Pan, Zijian; Zhang, Wenting [School of Electronic and Information Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, Liang; Liu, Jinliang; Zhang, Zhongbing; Ouyang, Xiaoping [Radiation Detection Research Center, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

    2016-04-25

    The pulse radiation detectors are sorely needed in the fields of nuclear reaction monitoring, material analysis, astronomy study, spacecraft navigation, and space communication. In this work, we demonstrate a nanosecond X-ray detector based on ZnO single crystal semiconductor, which emerges as a promising compound-semiconductor radiation detection material for its high radiation tolerance and advanced large-size bulk crystal growth technique. The resistivity of the ZnO single crystal is as high as 10{sup 13} Ω cm due to the compensation of the donor defects (V{sub O}) and acceptor defects (V{sub Zn} and O{sub i}) after high temperature annealing in oxygen. The photoconductive X-ray detector was fabricated using the high resistivity ZnO single crystal. The rise time and fall time of the detector to a 10 ps pulse electron beam are 0.8 ns and 3.3 ns, respectively, indicating great potential for ultrafast X-ray detection applications.

  15. The interchangeability of radioisotope and X-ray based measurements of bone mineral density

    International Nuclear Information System (INIS)

    Adachi, J.D.; Webber, C.E.

    1991-01-01

    Lumbar spine and femoral neck bone mineral density (BMD) were measured with a Novo radioisotope based dual photon densitometer and with a Lunar X-ray densitometer in 94 subjects attending a Metabolic Bone Disease Clinic. There was a strong correlation between results obtained from each machine. The correlation coefficients for the spine and femoral neck were 0.97 and 0.88, respectively. Differences between results from each machine were normally distributed with a mean bias of 37.5% (spine) and 27.8% (femur), arising principally from differences in machine calibration. In each case the BMD was greater measured by X-ray absorptiometry. The range for the bias was approximately 25-50% for the spine and 10-45% for the femoral neck. The results from these two machines are not interchangeable. When subjects participating in long term studies using a radioisotope densitometer are transferred to an X-ray densitometer, an individual conversion factor must be measured at each site for each subject. (author)

  16. Voxel-based Monte Carlo simulation of X-ray imaging and spectroscopy experiments

    International Nuclear Information System (INIS)

    Bottigli, U.; Brunetti, A.; Golosio, B.; Oliva, P.; Stumbo, S.; Vincze, L.; Randaccio, P.; Bleuet, P.; Simionovici, A.; Somogyi, A.

    2004-01-01

    A Monte Carlo code for the simulation of X-ray imaging and spectroscopy experiments in heterogeneous samples is presented. The energy spectrum, polarization and profile of the incident beam can be defined so that X-ray tube systems as well as synchrotron sources can be simulated. The sample is modeled as a 3D regular grid. The chemical composition and density is given at each point of the grid. Photoelectric absorption, fluorescent emission, elastic and inelastic scattering are included in the simulation. The core of the simulation is a fast routine for the calculation of the path lengths of the photon trajectory intersections with the grid voxels. The voxel representation is particularly useful for samples that cannot be well described by a small set of polyhedra. This is the case of most naturally occurring samples. In such cases, voxel-based simulations are much less expensive in terms of computational cost than simulations on a polygonal representation. The efficient scheme used for calculating the path lengths in the voxels and the use of variance reduction techniques make the code suitable for the detailed simulation of complex experiments on generic samples in a relatively short time. Examples of applications to X-ray imaging and spectroscopy experiments are discussed

  17. Compact gain saturated plasma based X-ray lasers down to 6.9nm

    Science.gov (United States)

    Rocca, Jorge; Wang, Y.; Wang, S.; Rockwood, A.; Berrill, M.; Shlyaptsev, V.

    2017-10-01

    Plasma based soft x-ray amplifiers allow many experiments requiring bright, high energy soft x-ray laser pulses to be conducted in compact facilities. We have extended the wavelength of compact gain saturated x-ray lasers to 6.89 nm in a Ni-like Gd plasma generated by a Ti:Sa laser. Gain saturated laser operation was also obtained at 7.36 nm in Ni-like Sm. Isolectronic scaling and optimization of laser pre-pulse duration allowed us to also observe strong lasing at 6.6 nm and 6.1 nm in Ni-like Tb, and amplification at 6.4 nm and 5.89 nm in Ni-like Dy. The results were obtained by transient laser heating of solid targets with traveling wave excitation at progressively increased gracing incidence angles. We show that the optimum pump angle of incidence for collisional Ni-like lasers increases linearly with atomic number from Z =42 to Z =66, reaching 43 degrees for Ni-like Dy, in good agreement with hydrodynamic/atomic physics simulations. These results will enable single-shot nano-scale imaging and other application of sub-7 nm lasers to be performed at compact facilities. Work supported by Grant DE-FG02-4ER15592 of the Department of Energy, Office of Science, and by the National Science Foundation Grant ECCS 1509925.

  18. Voxel-based Monte Carlo simulation of X-ray imaging and spectroscopy experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bottigli, U. [Istituto di Matematica e Fisica dell' Universita di Sassari, via Vienna 2, 07100, Sassari (Italy); Sezione INFN di Cagliari (Italy); Brunetti, A. [Istituto di Matematica e Fisica dell' Universita di Sassari, via Vienna 2, 07100, Sassari (Italy); Golosio, B. [Istituto di Matematica e Fisica dell' Universita di Sassari, via Vienna 2, 07100, Sassari (Italy) and Sezione INFN di Cagliari (Italy)]. E-mail: golosio@uniss.it; Oliva, P. [Istituto di Matematica e Fisica dell' Universita di Sassari, via Vienna 2, 07100, Sassari (Italy); Stumbo, S. [Istituto di Matematica e Fisica dell' Universita di Sassari, via Vienna 2, 07100, Sassari (Italy); Vincze, L. [Department of Chemistry, University of Antwerp (Belgium); Randaccio, P. [Dipartimento di Fisica dell' Universita di Cagliari and Sezione INFN di Cagliari (Italy); Bleuet, P. [European Synchrotron Radiation Facility, Grenoble (France); Simionovici, A. [European Synchrotron Radiation Facility, Grenoble (France); Somogyi, A. [European Synchrotron Radiation Facility, Grenoble (France)

    2004-10-08

    A Monte Carlo code for the simulation of X-ray imaging and spectroscopy experiments in heterogeneous samples is presented. The energy spectrum, polarization and profile of the incident beam can be defined so that X-ray tube systems as well as synchrotron sources can be simulated. The sample is modeled as a 3D regular grid. The chemical composition and density is given at each point of the grid. Photoelectric absorption, fluorescent emission, elastic and inelastic scattering are included in the simulation. The core of the simulation is a fast routine for the calculation of the path lengths of the photon trajectory intersections with the grid voxels. The voxel representation is particularly useful for samples that cannot be well described by a small set of polyhedra. This is the case of most naturally occurring samples. In such cases, voxel-based simulations are much less expensive in terms of computational cost than simulations on a polygonal representation. The efficient scheme used for calculating the path lengths in the voxels and the use of variance reduction techniques make the code suitable for the detailed simulation of complex experiments on generic samples in a relatively short time. Examples of applications to X-ray imaging and spectroscopy experiments are discussed.

  19. An X-ray beam position monitor based on the photoluminescence of helium gas

    Science.gov (United States)

    Revesz, Peter; White, Jeffrey A.

    2005-03-01

    A new method for white beam position monitoring for both bend magnet and wiggler synchrotron X-ray radiation has been developed. This method utilizes visible light luminescence generated as a result of ionization by the intense X-ray flux. In video beam position monitors (VBPMs), the luminescence of helium gas at atmospheric pressure is observed through a view port using a CCD camera next to the beam line. The beam position, profile, integrated intensity and FWHM are calculated from the distribution of luminescence intensity in each captured image by custom software. Misalignment of upstream apertures changes the image profile making VBPMs helpful for initial alignment of upstream beam line components. VBPMs can thus provide more information about the X-ray beam than most beam position monitors (BPMs). A beam position calibration procedure, employing a tilted plane-parallel glass plate placed in front of the camera lens, has also been developed. The accuracy of the VBPM system was measured during a bench-top experiment to be better than 1 μm. The He-luminescence-based VBPM system has been operative on three CHESS beam lines (F hard-bend and wiggler, A-line wiggler and G-line wiggler) for about a year. The beam positions are converted to analog voltages and used as feedback signals for beam stabilization. In our paper we discuss details of VBPM construction and describe further results of its performance.

  20. X-ray crystallography

    Science.gov (United States)

    2001-01-01

    X-rays diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an X-ray crystallographer shines X-rays through the crystal. Unlike a single dental X-ray, which produces a shadow image of a tooth, these X-rays have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the X-rays after they diffract through the crystal. The X-rays bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.

  1. Design and image-quality performance of high resolution CMOS-based X-ray imaging detectors for digital mammography

    Science.gov (United States)

    Cha, B. K.; Kim, J. Y.; Kim, Y. J.; Yun, S.; Cho, G.; Kim, H. K.; Seo, C.-W.; Jeon, S.; Huh, Y.

    2012-04-01

    In digital X-ray imaging systems, X-ray imaging detectors based on scintillating screens with electronic devices such as charge-coupled devices (CCDs), thin-film transistors (TFT), complementary metal oxide semiconductor (CMOS) flat panel imagers have been introduced for general radiography, dental, mammography and non-destructive testing (NDT) applications. Recently, a large-area CMOS active-pixel sensor (APS) in combination with scintillation films has been widely used in a variety of digital X-ray imaging applications. We employed a scintillator-based CMOS APS image sensor for high-resolution mammography. In this work, both powder-type Gd2O2S:Tb and a columnar structured CsI:Tl scintillation screens with various thicknesses were fabricated and used as materials to convert X-ray into visible light. These scintillating screens were directly coupled to a CMOS flat panel imager with a 25 × 50 mm2 active area and a 48 μm pixel pitch for high spatial resolution acquisition. We used a W/Al mammographic X-ray source with a 30 kVp energy condition. The imaging characterization of the X-ray detector was measured and analyzed in terms of linearity in incident X-ray dose, modulation transfer function (MTF), noise-power spectrum (NPS) and detective quantum efficiency (DQE).

  2. Study Of Soot Growth And Nucleation By A Time-Resolved Synchrotron Radiation Based X-Ray Absorption Method

    National Research Council Canada - National Science Library

    Mitchell, Judith I

    2001-01-01

    This report results from a contract tasking University of Rennes I as follows: The contractor will perform a study of soot growth and nucleation by a time-resolved synchrotron radiation based x-ray absorption method...

  3. The fractional Fourier transform as a simulation tool for lens-based X-ray microscopy

    DEFF Research Database (Denmark)

    Pedersen, Anders Filsøe; Simons, Hugh; Detlefs, Carsten

    2018-01-01

    The fractional Fourier transform (FrFT) is introduced as a tool for numerical simulations of X-ray wavefront propagation. By removing the strict sampling requirements encountered in typical Fourier optics, simulations using the FrFT can be carried out with much decreased detail, allowing...... the attenuation from the entire CRL using one or two effective apertures without loss of accuracy, greatly accelerating simulations involving CRLs. To demonstrate the applicability and accuracy of the FrFT, the imaging resolution of a CRL-based imaging system is estimated, and the FrFT approach is shown...

  4. Mask-based dual-axes tomoholography using soft x-rays

    International Nuclear Information System (INIS)

    Guehrs, Erik; Frömmel, Stefanie; Günther, Christian M; Hessing, Piet; Schneider, Michael; Shemilt, Laura; Eisebitt, Stefan; Fohler, Manuel

    2015-01-01

    We explore tomographic mask-based Fourier transform x-ray holography with respect to the use of a thin slit as a reference wave source. This imaging technique exclusively uses the interference between the waves scattered by the object and the slit simplifying the experimental realization and ensuring high data quality. Furthermore, we introduce a second reference slit to rotate the sample around a second axis and to record a dual-axes tomogram. Compared to a single-axis tomogram, the reconstruction artifacts are decreased in accordance with the reduced missing data wedge. Two demonstration experiments are performed where test structures are imaged with a lateral resolution below 100 nm. (paper)

  5. USB port compatible virtual instrument based automation for x-ray diffractometer setup

    International Nuclear Information System (INIS)

    Jayapandian, J.; Sheela, O.K.; Mallika, R.; Thiruarul, A.; Purniah, B.

    2004-01-01

    Windows based virtual instrument (VI) programs in graphic language simplify the design automation in R and D laboratories. With minimal hardware and maximum support of software, the automation becomes easier and user friendly. A novel design approach for the automation of SIEMENS make x-ray diffractometer setup is described in this paper. The automation is achieved with an indigenously developed virtual instrument program in labVIEW ver.6.0 and with a simple hardware design using 89C2051 micro-controller compatible with PC's USB port for the total automation of the experiment. (author)

  6. A Fundamental Parameter-Based Calibration Model for an Intrinsic Germanium X-Ray Fluorescence Spectrometer

    DEFF Research Database (Denmark)

    Christensen, Leif Højslet; Pind, Niels

    1982-01-01

    A matrix-independent fundamental parameter-based calibration model for an energy-dispersive X-ray fluorescence spectrometer has been developed. This model, which is part of a fundamental parameter approach quantification method, accounts for both the excitation and detection probability. For each...... secondary target a number of relative calibration constants are calculated on the basis of knowledge of the irradiation geometry, the detector specifications, and tabulated fundamental physical parameters. The absolute calibration of the spectrometer is performed by measuring one pure element standard per...

  7. Computer simulation for synchrotron radiation based X-ray fluorescent microtomography

    International Nuclear Information System (INIS)

    Deng Biao; Yu Xiaohan; Xu Hongjie

    2007-01-01

    Synchrotron radiation based fluorescent microtomography (SR-XFMT) is a nondestructive technique for detecting elemental composition and distribution inside a specimen with high spatial resolution and sensitivity, and will be an optional experimental technique at SSRF hard X-ray micro-focusing beamline now under construction. In this paper, the principles and developments of SR-XFMT are briefly introduced. Computer simulation of SR-XFMT experiment is performed. The image of the simulated sample is reconstructed using Filtered Back Projection (FBP), Algebraic Reconstruction Techniques (ART) and modified FBP with absorption correction. The qualities of the reconstructed images are analyzed and compared. The validity of these reconstruction techniques is discussed. (authors)

  8. Role of base damage in aberration formation: interaction of aphidicolin and x-rays

    International Nuclear Information System (INIS)

    Bender, M.A.; Preston, R.J.

    1981-01-01

    The base analog cytosine arabinoside (CA) is an inhibitor of DNA synthesis that is able to induce chromosomal aberrations not only in the DNA synthetic (S) phase of the cell cycle but in cells in the pre- (G 0 or G 1 ) and in the post-DNA-synthetic (G 2 ) phases of the cell cycle as well. Incubation of human peripheral lymphocytes in CA following either G 0 or G 2 x irradiation causes a synergistic increase in chromosomal aberration frequency. CA is believed to preferentially inhibit DNA polymerase α. It is suggested that it is inhibition of the repair of x-ray-induced base damage that is responsible for the synergistic effect on chromosomal aberration production observed with x-ray and CA treatment of human peripheral lymphocytes. It has also been observed that CA induces sister chromatid exchanges (SCE) in mammalian cells when present during normal DNA replication and that it also interacts synergistically with uv in the induction of SCE. A number of other inhibitors of DNA synthesis were also tested, one, aphidicolin (APC), did produce effects similar to CA at the same concentration. Aphidicolin is a tetracyclic diterpinoid that inhibits the growth of eukaryotic cells by inhibition of DNA synthesis. This action has been shown to result from specific inhibition of DNA polymerase α, but not of polymerases β or γ. Unlike CA, it seems likely that APC inhibits by binding to and inactivating the DNA-α polymerase complex. Because both CA and APC are α polymerase inhibitors and because both interact synergistically with uv in the production of SCE, studies were conducted to determine whether APC also shares other cytogenetic properties of CA. Results to date have shown that, like CA, APC is clastogenic in both G 0 and G 2 , and it also interacts synergistically with x rays to increase chromosomal aberration production in both G 0 and G 2

  9. Site- and phase-selective x-ray absorption spectroscopy based on phase-retrieval calculation

    International Nuclear Information System (INIS)

    Kawaguchi, Tomoya; Fukuda, Katsutoshi; Matsubara, Eiichiro

    2017-01-01

    Understanding the chemical state of a particular element with multiple crystallographic sites and/or phases is essential to unlocking the origin of material properties. To this end, resonant x-ray diffraction spectroscopy (RXDS) achieved through a combination of x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) techniques can allow for the measurement of diffraction anomalous fine structure (DAFS). This is expected to provide a peerless tool for electronic/local structural analyses of materials with complicated structures thanks to its capability to extract spectroscopic information about a given element at each crystallographic site and/or phase. At present, one of the major challenges for the practical application of RXDS is the rigorous determination of resonant terms from observed DAFS, as this requires somehow determining the phase change in the elastic scattering around the absorption edge from the scattering intensity. This is widely known in the field of XRD as the phase problem. The present review describes the basics of this problem, including the relevant background and theory for DAFS and a guide to a newly-developed phase-retrieval method based on the logarithmic dispersion relation that makes it possible to analyze DAFS without suffering from the intrinsic ambiguities of conventional iterative-fitting. Several matters relating to data collection and correction of RXDS are also covered, with a final emphasis on the great potential of powder-sample-based RXDS (P-RXDS) to be used in various applications relevant to practical materials, including antisite-defect-type electrode materials for lithium-ion batteries. (topical review)

  10. Indirect X-ray Detectors Based on Inkjet-Printed Photodetectors with a Screen-Printed Scintillator Layer.

    Science.gov (United States)

    Oliveira, Juliana; Correia, Vitor; Sowade, Enrico; Etxebarria, Ikerne; Rodriguez, Raul D; Mitra, Kalyan Y; Baumann, Reinhard R; Lanceros-Mendez, Senentxu

    2018-04-18

    Organic photodetectors (PDs) based on printing technologies will allow to expand the current field of PD applications toward large-area and flexible applications in areas such as medical imaging, security, and quality control, among others. Inkjet printing is a powerful digital tool for the deposition of smart and functional materials on various substrates, allowing the development of electronic devices such as PDs on various substrates. In this work, inkjet-printed PD arrays, based on the organic thin-film transistor architecture, have been developed and applied for the indirect detection of X-ray radiation using a scintillator ink as an X-ray absorber. The >90% increase of the photocurrent of the PDs under X-ray radiation, from about 53 nA without the scintillator film to about 102 nA with the scintillator located on top of the PD, proves the suitability of the developed printed device for X-ray detection applications.

  11. Analyzer-based x-ray phase-contrast microscopy combining channel-cut and asymmetrically cut crystals

    International Nuclear Information System (INIS)

    Hoennicke, M. G.; Cusatis, C.

    2007-01-01

    An analyzer-based x-ray phase-contrast microscopy (ABM) setup combining a standard analyzer-based x-ray phase-contrast imaging (ABI) setup [nondispersive 4-crystal setup (Bonse-Hart setup)] and diffraction by asymmetrically cut crystals is presented here. An attenuation-contrast microscopy setup with conventional x-ray source and asymmetrically cut crystals is first analyzed. Edge-enhanced effects attributed to phase jumps or refraction/total external reflection on the fiber borders were detected. However, the long exposure times and the possibility to achieve high contrast microscopies by using extremely low attenuation-contrast samples motivated us to assemble the ABM setup using a synchrotron source. This setup was found to be useful for low contrast attenuation samples due to the low exposure time, high contrast, and spatial resolution found. Moreover, thanks to the combination with the nondispersive ABI setup, the diffraction-enhanced x-ray imaging algorithm could be applied

  12. Noise texture and signal detectability in propagation-based x-ray phase-contrast tomography

    International Nuclear Information System (INIS)

    Chou, Cheng-Ying; Anastasio, Mark A.

    2010-01-01

    Purpose: X-ray phase-contrast tomography (PCT) is a rapidly emerging imaging modality for reconstructing estimates of an object's three-dimensional x-ray refractive index distribution. Unlike conventional x-ray computed tomography methods, the statistical properties of the reconstructed images in PCT remain unexplored. The purpose of this work is to quantitatively investigate noise propagation in PCT image reconstruction. Methods: The authors derived explicit expressions for the autocovariance of the reconstructed absorption and refractive index images to characterize noise texture and understand how the noise properties are influenced by the imaging geometry. Concepts from statistical detection theory were employed to understand how the imaging geometry-dependent statistical properties affect the signal detection performance in a signal-known-exactly/background-known-exactly task. Results: The analytical formulas for the phase and absorption autocovariance functions were implemented numerically and compared to the corresponding empirical values, and excellent agreement was found. They observed that the reconstructed refractive images are highly spatially correlated, while the absorption images are not. The numerical results confirm that the strength of the covariance is scaled by the detector spacing. Signal detection studies were conducted, employing a numerical observer. The detection performance was found to monotonically increase as the detector-plane spacing was increased. Conclusions: The authors have conducted the first quantitative investigation of noise propagation in PCT image reconstruction. The reconstructed refractive images were found to be highly spatially correlated, while absorption images were not. This is due to the presence of a Fourier space singularity in the reconstruction formula for the refraction images. The statistical analysis may facilitate the use of task-based image quality measures to further develop and optimize this emerging

  13. Noise texture and signal detectability in propagation-based x-ray phase-contrast tomography

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Cheng-Ying; Anastasio, Mark A. [Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei, Taiwan 106, Taiwan (China); Department of Biomedical Engineering, Medical Imaging Research Center, Illinois Institute of Technology, 3440 S. Dearborn Street, E1-116, Chicago, Illinois 60616 (United States)

    2010-01-15

    Purpose: X-ray phase-contrast tomography (PCT) is a rapidly emerging imaging modality for reconstructing estimates of an object's three-dimensional x-ray refractive index distribution. Unlike conventional x-ray computed tomography methods, the statistical properties of the reconstructed images in PCT remain unexplored. The purpose of this work is to quantitatively investigate noise propagation in PCT image reconstruction. Methods: The authors derived explicit expressions for the autocovariance of the reconstructed absorption and refractive index images to characterize noise texture and understand how the noise properties are influenced by the imaging geometry. Concepts from statistical detection theory were employed to understand how the imaging geometry-dependent statistical properties affect the signal detection performance in a signal-known-exactly/background-known-exactly task. Results: The analytical formulas for the phase and absorption autocovariance functions were implemented numerically and compared to the corresponding empirical values, and excellent agreement was found. They observed that the reconstructed refractive images are highly spatially correlated, while the absorption images are not. The numerical results confirm that the strength of the covariance is scaled by the detector spacing. Signal detection studies were conducted, employing a numerical observer. The detection performance was found to monotonically increase as the detector-plane spacing was increased. Conclusions: The authors have conducted the first quantitative investigation of noise propagation in PCT image reconstruction. The reconstructed refractive images were found to be highly spatially correlated, while absorption images were not. This is due to the presence of a Fourier space singularity in the reconstruction formula for the refraction images. The statistical analysis may facilitate the use of task-based image quality measures to further develop and optimize this emerging

  14. Template-based CTA to x-ray angio rigid registration of coronary arteries in frequency domain with automatic x-ray segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Aksoy, Timur; Unal, Gozde [Sabanci University, Tuzla, Istanbul 34956 (Turkey); Demirci, Stefanie; Navab, Nassir [Computer Aided Medical Procedures (CAMP), Technical University of Munich, Garching, 85748 (Germany); Degertekin, Muzaffer [Yeditepe University Hospital, Istanbul 34752 (Turkey)

    2013-10-15

    Purpose: A key challenge for image guided coronary interventions is accurate and absolutely robust image registration bringing together preinterventional information extracted from a three-dimensional (3D) patient scan and live interventional image information. In this paper, the authors present a novel scheme for 3D to two-dimensional (2D) rigid registration of coronary arteries extracted from preoperative image scan (3D) and a single segmented intraoperative x-ray angio frame in frequency and spatial domains for real-time angiography interventions by C-arm fluoroscopy.Methods: Most existing rigid registration approaches require a close initialization due to the abundance of local minima and high complexity of search algorithms. The authors' method eliminates this requirement by transforming the projections into translation-invariant Fourier domain for estimating the 3D pose. For 3D rotation recovery, template Digitally Reconstructed Radiographs (DRR) as candidate poses of 3D vessels of segmented computed tomography angiography are produced by rotating the camera (image intensifier) around the DICOM angle values with a specific range as in C-arm setup. The authors have compared the 3D poses of template DRRs with the segmented x-ray after equalizing the scales in three domains, namely, Fourier magnitude, Fourier phase, and Fourier polar. The best rotation pose candidate was chosen by one of the highest similarity measures returned by the methods in these domains. It has been noted in literature that frequency domain methods are robust against noise and occlusion which was also validated by the authors' results. 3D translation of the volume was then recovered by distance-map based BFGS optimization well suited to convex structure of the authors' objective function without local minima due to distance maps. A novel automatic x-ray vessel segmentation was also performed in this study.Results: Final results were evaluated in 2D projection space for

  15. Template-based CTA to x-ray angio rigid registration of coronary arteries in frequency domain with automatic x-ray segmentation

    International Nuclear Information System (INIS)

    Aksoy, Timur; Unal, Gozde; Demirci, Stefanie; Navab, Nassir; Degertekin, Muzaffer

    2013-01-01

    Purpose: A key challenge for image guided coronary interventions is accurate and absolutely robust image registration bringing together preinterventional information extracted from a three-dimensional (3D) patient scan and live interventional image information. In this paper, the authors present a novel scheme for 3D to two-dimensional (2D) rigid registration of coronary arteries extracted from preoperative image scan (3D) and a single segmented intraoperative x-ray angio frame in frequency and spatial domains for real-time angiography interventions by C-arm fluoroscopy.Methods: Most existing rigid registration approaches require a close initialization due to the abundance of local minima and high complexity of search algorithms. The authors' method eliminates this requirement by transforming the projections into translation-invariant Fourier domain for estimating the 3D pose. For 3D rotation recovery, template Digitally Reconstructed Radiographs (DRR) as candidate poses of 3D vessels of segmented computed tomography angiography are produced by rotating the camera (image intensifier) around the DICOM angle values with a specific range as in C-arm setup. The authors have compared the 3D poses of template DRRs with the segmented x-ray after equalizing the scales in three domains, namely, Fourier magnitude, Fourier phase, and Fourier polar. The best rotation pose candidate was chosen by one of the highest similarity measures returned by the methods in these domains. It has been noted in literature that frequency domain methods are robust against noise and occlusion which was also validated by the authors' results. 3D translation of the volume was then recovered by distance-map based BFGS optimization well suited to convex structure of the authors' objective function without local minima due to distance maps. A novel automatic x-ray vessel segmentation was also performed in this study.Results: Final results were evaluated in 2D projection space for patient data; and

  16. The nature of ancient Egyptian copper-containing carbon inks is revealed by synchrotron radiation based X-ray microscopy

    OpenAIRE

    Christiansen , Thomas; Cotte , Marine; Loredo-Portales , René; Lindelof , Poul ,; Mortensen , Kell; Ryholt , Kim; Larsen , Sine

    2017-01-01

    International audience; For the first time it is shown that carbon black inks on ancient Egyptian papyri from different time periods and geographical regions contain copper. The inks have been investigated using synchrotron-based micro X-ray fluorescence (XRF) and micro X-ray absorption near-edge structure spectroscopy (XANES) at the European Synchrotron Radiation Facility (ESRF). The composition of the copper-containing carbon inks showed no significant differences that could be related to t...

  17. Water equivalence of NIPAM based polymer gel dosimeters with enhanced sensitivity for x-ray CT

    Science.gov (United States)

    Gorjiara, Tina; Hill, Robin; Bosi, Stephen; Kuncic, Zdenka; Baldock, Clive

    2013-10-01

    Two new formulations of N-isopropylacrylamide (NIPAM) based three dimensional (3D) gel dosimeters have recently been developed with improved sensitivity to x-ray CT readout, one without any co-solvent and the other one with isopropanol co-solvent. The water equivalence of the NIPAM gel dosimeters was investigated using different methods to calculate their radiological properties including: density, electron density, number of electrons per grams, effective atomic number, photon interaction probabilities, mass attenuation and energy absorption coefficients, electron collisional, radiative and total mass stopping powers and electron mass scattering power. Monte Carlo modelling was also used to compare the dose response of these gel dosimeters with water for kilovoltage and megavoltage x-ray beams and for megavoltage electron beams. We found that the density and electron density of the co-solvent free gel dosimeter are more water equivalent with less than a 2.6% difference compared to a 5.7% difference for the isopropanol gel dosimeter. Both the co-solvent free and isopropanol solvent gel dosimeters have lower effective atomic numbers than water, differing by 2.2% and 6.5%, respectively. As a result, their photoelectric absorption interaction probabilities are up to 6% and 19% different from water, respectively. Compton scattering and pair production interaction probabilities of NIPAM gel with isopropanol differ by up to 10% from water while for the co-solvent free gel, the differences are 3%. Mass attenuation and energy absorption coefficients of the co-solvent free gel dosimeter and the isopropanol gel dosimeter are up to 7% and 19% lower than water, respectively. Collisional and total mass stopping powers of both gel dosimeters differ by less than 2% from those of water. The dose response of the co-solvent free gel dosimeter is water equivalent (with x-ray beams over the energy range 180 keV-18 MV, both gel dosimeters have less than 2% discrepancy with water. For

  18. Anatomical based registration of multi-sector x-ray images for panorama reconstruction

    Science.gov (United States)

    Ben-Zikri, Yehuda Kfir; Mendez, Stacy; Linte, Cristian A.

    2017-03-01

    Accurate measurement of long limb alignment is an essential stage of the pre-operative planning of realignment surgery. This alignment is quantified according to the hip-knee-ankle (HKA) angle of the mechanical axis of the lower extremity and is measured based on a full-length weight-bearing X-ray or standard computed radiography (CR) image of the patient in standing position. Due to the limited field-of-view of the traditionally employed digital X-ray imaging systems, several sector images are required to capture the posture of a standing individual. These sector images need to then be "stitched" together to reconstruct the standing posture. To eliminate user-induced variability and time constraints associated with the traditional manual "stitching" protocol, we have created an image processing application to automate the stitching process, when there are no reliable external markers available in the images, by only relying on the most reliable anatomical content of the image. The application starts with a rough segmentation of the tibia and the sector images are then registered by evaluating the DICE coefficient between the edges of these corresponding bones along the medial edge. The identified translations are then used to register the original sector images into the standing panorama image. To test the robustness of our method, we randomly selected 40 datasets from a variant database consisting of nearly 100 patient X-ray images acquired for patient screening as part of a multi-site clinical trial. The resulting horizontal and vertical translation values from the automated registration were compared to the homologous translations recorded during the manual panorama generation conducted by a knowledgeable X-ray imaging technician. The mean and standard deviation of the differences for the horizontal translation parameters was -0:27+/-1:14 mm and 0:31+/-1:86 mm for the left and right tibia, respectively. The vertical translation differences for the left and

  19. Experimental Validation of Pulse Phase Tracking for X-Ray Pulsar Based

    Science.gov (United States)

    Anderson, Kevin

    2012-01-01

    Pulsars are a form of variable celestial source that have shown to be usable as aids for autonomous, deep space navigation. Particularly those sources emitting in the X-ray band are ideal for navigation due to smaller detector sizes. In this paper X-ray photons arriving from a pulsar are modeled as a non-homogeneous Poisson process. The method of pulse phase tracking is then investigated as a technique to measure the radial distance traveled by a spacecraft over an observation interval. A maximum-likelihood phase estimator (MLE) is used for the case where the observed frequency signal is constant. For the varying signal frequency case, an algorithm is used in which the observation window is broken up into smaller blocks over which an MLE is used. The outputs of this phase estimation process were then looped through a digital phase-locked loop (DPLL) in order to reduce the errors and produce estimates of the doppler frequency. These phase tracking algorithms were tested both in a computer simulation environment and using the NASA Goddard Space flight Center X-ray Navigation Laboratory Testbed (GXLT). This provided an experimental validation with photons being emitted by a modulated X-ray source and detected by a silicon-drift detector. Models of the Crab pulsar and the pulsar B1821-24 were used in order to generate test scenarios. Three different simulated detector trajectories were used to be tracked by the phase tracking algorithm: a stationary case, one with constant velocity, and one with constant acceleration. All three were performed in one-dimension along the line of sight to the pulsar. The first two had a constant signal frequency and the third had a time varying frequency. All of the constant frequency cases were processed using the MLE, and it was shown that they tracked the initial phase within 0.15% for the simulations and 2.5% in the experiments, based on an average of ten runs. The MLE-DPLL cascade version of the phase tracking algorithm was used in

  20. Coelectrodeposition of Ternary Mn-Oxide/Polypyrrole Composites for ORR Electrocatalysts: A Study Based on Micro-X-ray Absorption Spectroscopy and X-ray Fluorescence Mapping

    Directory of Open Access Journals (Sweden)

    Benedetto Bozzini

    2015-08-01

    Full Text Available Low energy X-ray fluorescence (XRF and soft X-ray absorption (XAS microspectroscopies at high space-resolution are employed for the investigation of the coelectrodeposition of composites consisting of a polypyrrole(PPy-matrix and Mn-based ternary dispersoids, that have been proposed as promising electrocatalysts for oxygen-reduction electrodes. Specifically, we studied Mn–Co–Cu/PP, Mn–Co–Mg/PPy and Mn–Ni–Mg/PPy co-electrodeposits. The Mn–Co–Cu system features the best ORR electrocatalytic activity in terms of electron transfer number, onset potential, half-wave potential and current density. XRF maps and micro-XAS spectra yield compositional and chemical state distributions, contributing unique molecular-level information on the pulse-plating processes. Mn, Ni, Co and Mg exhibit a bimodal distribution consisting of mesoscopic aggregates of micrometric globuli, separated by polymer-rich ridges. Within this common qualitative scenario, the individual systems exhibit quantitatively different chemical distribution patterns, resulting from specific electrokinetic and electrosorption properties of the single components. The electrodeposits consist of Mn3+,4+-oxide particles, accompanied by combinations of Co0/Co2+, Ni0/Ni2+ and Cu0,+/Cu2+ resulting from the alternance of cathodic and anodic pulses. The formation of highly electroactive Mn3+,4+ in the as-fabricated material is a specific feature of the ternary systems, deriving from synergistic stabilisation brought about by two types of bivalent dopants as well as by galvanic contact to elemental metal; this result represents a considerable improvement in material quality with respect to previously studied Mn/PPy and Mn-based/PPy binaries.

  1. Scintillation properties and X-ray irradiation hardness of Ce3+-doped Gd2O3-based scintillation glass

    International Nuclear Information System (INIS)

    Liu, Liwan; Shao, Chongyun; Zhang, Yu; Liao, Xili; Yang, Qiuhong; Hu, Lili; Chen, Danping

    2016-01-01

    Ce 3+ -doped Gd 2 O 3 -based scintillation glasses are prepared within an air or CO atmosphere. The effects of fluorine, lutetium, barium, and the melting atmosphere on the optical properties, scintillation properties and irradiation hardness are studied. Absorption spectra, luminescence spectra under UV and X-ray excitation, and the X-ray radiation-induced spectra are presented. The results show that the density can be increased by doping with fluorine, lutetium and barium. The luminescence intensity decreases after X-ray irradiation. Because of charge transfer quenching, fluorine and lutetium enhance the UV-excited and X-ray excited luminescence intensity, but barium decreases. Moreover, fluorine and lutetium are advantageous to irradiation hardness while barium is not. In addition, a non-reducing atmosphere provides a higher irradiation hardness than a reducing atmosphere. Fluorine-doped glass is promising to enhance luminescence intensity, promote irradiation hardness, and increase the density.

  2. The source of X-rays and high-charged ions based on moderate power vacuum discharge with laser triggering

    Directory of Open Access Journals (Sweden)

    Alkhimova Mariya A.

    2015-06-01

    Full Text Available The source of X-ray radiation with the energy of quanta that may vary in the range hν = 1÷12 keV was developed for studies in X-ray interaction with matter and modification of solid surfaces. It was based on a vacuum spark discharge with the laser triggering. It was shown in our experiments that there is a possibility to adjust X-ray radiation spectrum by changing the configuration of the electrode system when the energy stored in the capacitor is varied within the range of 1÷17 J. A comprehensive study of X-ray imaging and quanta energy was carried out. These experiments were carried out for the case of both direct and reverse polarity of the voltage on the electrodes. Additionally, ion composition of plasma created in a laser-triggered vacuum discharge was analyzed. Highly charged ions Zn(+21, Cu(+20 and Fe(+18 were observed.

  3. R and D Toward a Compact High-Brilliance X-Ray Source Based on Channeling Radiation

    International Nuclear Information System (INIS)

    Piot, P.; Brau, C.A.; Gabella, W.E.; Choi, B.K.; Jarvis, J.D.; Mendenhall, M.H.; Lewellen, J.W.; Mihalcea, D.

    2012-01-01

    X-rays have been valuable to a large number of fields including Science, Medicine, and Security. Yet, the availability of a compact high-spectral brilliance X-ray sources is limited. A technique to produce X-rays with spectral brilliance B ∼ 10 12 photons.(mm-mrd) -2 .(0.1% BW) -1 .s -1 is discussed. The method is based on the generation and acceleration of a low-emittance field-emitted electron bunches. The bunches are then focused on a diamond crystal thereby producing channeling radiation. In this paper, after presenting the overarching concept, we discuss the generation, acceleration and transport of the low-emittance bunches with parameters consistent with the production of high-brilliance X-rays through channeling radiation. We especially consider the example of the Advanced Superconducting Test Accelerator (ASTA) currently in construction at Fermilab where a proof-of-principle experiment is in preparation.

  4. The effect of dose enhancement near metal interfaces on synthetic diamond based X-ray dosimeters

    Science.gov (United States)

    Alamoudi, D.; Lohstroh, A.; Albarakaty, H.

    2017-11-01

    This study investigates the effects of dose enhancement on the photocurrent performance at metallic interfaces in synthetic diamond detectors based X-ray dosimeters as a function of bias voltages. Monte Carlo (MC) simulations with the BEAMnrc code were carried out to simulate the dose enhancement factor (DEF) and compared against the equivalent photocurrent ratio from experimental investigations. The MC simulation results show that the sensitive region for the absorbed dose distribution covers a few micrometers distances from the interface. Experimentally, two single crystals (SC) and one polycrystalline (PC) synthetic diamond samples were fabricated into detectors with carbon based electrodes by boron and carbon ion implantation. Subsequently; the samples were each mounted inside a tissue equivalent encapsulation to minimize unintended fluence perturbation. Dose enhancement was generated by placing copper, lead or gold near the active volume of the detectors using 50 kVp and 100 kVp X-rays relevant for medical dosimetry. The results show enhancement in the detectors' photocurrent performance when different metals are butted up to the diamond bulk as expected. The variation in the photocurrent measurement depends on the type of diamond samples, their electrodes' fabrication and the applied bias voltages indicating that the dose enhancement near the detector may modify their electronic performance.

  5. Carbon-based Fresnel optics for hard x-ray astronomy.

    Science.gov (United States)

    Braig, Christoph; Zizak, Ivo

    2018-03-10

    We investigate the potential of large-scale diffractive-refractive normal-incidence transmission lenses for the development of space-based hard x-ray telescopes with an angular resolution in the range of (10 -6 -10 -3 )  arcsec over a field of view that is restricted by the available detector size. Coherently stepped achromatic lenses with diameters up to 5 m for compact apertures and 13 m in the case of segmentation provide an access to spectrally resolved imaging within keV-wide bands around the design energy between 10 and 30 keV. Within an integration time of 10 6   s, a photon-limited 5σ sensitivity down to (10 -9 -10 -7 )  s -1  cm -2  keV -1 can be achieved depending on the specific design. An appropriate fabrication strategy, feasible nowadays with micro-optical technologies, is considered and relies on the availability of high-purity carbon or polymer membranes. X-ray fluorescence measurements of various commercially available carbon-based materials prove for most of them the existence of a virtually negligible contamination by critical trace elements such as transition metals on the ppm level.

  6. CdTe Based Hard X-ray Imager Technology For Space Borne Missions

    Science.gov (United States)

    Limousin, Olivier; Delagnes, E.; Laurent, P.; Lugiez, F.; Gevin, O.; Meuris, A.

    2009-01-01

    CEA Saclay has recently developed an innovative technology for CdTe based Pixelated Hard X-Ray Imagers with high spectral performance and high timing resolution for efficient background rejection when the camera is coupled to an active veto shield. This development has been done in a R&D program supported by CNES (French National Space Agency) and has been optimized towards the Simbol-X mission requirements. In the latter telescope, the hard X-Ray imager is 64 cm² and is equipped with 625µm pitch pixels (16384 independent channels) operating at -40°C in the range of 4 to 80 keV. The camera we demonstrate in this paper consists of a mosaic of 64 independent cameras, divided in 8 independent sectors. Each elementary detection unit, called Caliste, is the hybridization of a 256-pixel Cadmium Telluride (CdTe) detector with full custom front-end electronics into a unique 1 cm² component, juxtaposable on its four sides. Recently, promising results have been obtained from the first micro-camera prototypes called Caliste 64 and will be presented to illustrate the capabilities of the device as well as the expected performance of an instrument based on it. The modular design of Caliste enables to consider extended developments toward IXO type mission, according to its specific scientific requirements.

  7. Quantitative breast tissue characterization using grating-based x-ray phase-contrast imaging

    Science.gov (United States)

    Willner, M.; Herzen, J.; Grandl, S.; Auweter, S.; Mayr, D.; Hipp, A.; Chabior, M.; Sarapata, A.; Achterhold, K.; Zanette, I.; Weitkamp, T.; Sztrókay, A.; Hellerhoff, K.; Reiser, M.; Pfeiffer, F.

    2014-04-01

    X-ray phase-contrast imaging has received growing interest in recent years due to its high capability in visualizing soft tissue. Breast imaging became the focus of particular attention as it is considered the most promising candidate for a first clinical application of this contrast modality. In this study, we investigate quantitative breast tissue characterization using grating-based phase-contrast computed tomography (CT) at conventional polychromatic x-ray sources. Different breast specimens have been scanned at a laboratory phase-contrast imaging setup and were correlated to histopathology. Ascertained tumor types include phylloides tumor, fibroadenoma and infiltrating lobular carcinoma. Identified tissue types comprising adipose, fibroglandular and tumor tissue have been analyzed in terms of phase-contrast Hounsfield units and are compared to high-quality, high-resolution data obtained with monochromatic synchrotron radiation, as well as calculated values based on tabulated tissue properties. The results give a good impression of the method’s prospects and limitations for potential tumor detection and the associated demands on such a phase-contrast breast CT system. Furthermore, the evaluated quantitative tissue values serve as a reference for simulations and the design of dedicated phantoms for phase-contrast mammography.

  8. High resolution X-ray detector for synchrotron-based microtomography

    CERN Document Server

    Stampanoni, M; Wyss, P; Abela, R; Patterson, B; Hunt, S; Vermeulen, D; Rueegsegger, P

    2002-01-01

    Synchrotron-based microtomographic devices are powerful, non-destructive, high-resolution research tools. Highly brilliant and coherent X-rays extend the traditional absorption imaging techniques and enable edge-enhanced and phase-sensitive measurements. At the Materials Science Beamline MS of the Swiss Light Source (SLS), the X-ray microtomographic device is now operative. A high performance detector based on a scintillating screen optically coupled to a CCD camera has been developed and tested. Different configurations are available, covering a field of view ranging from 715x715 mu m sup 2 to 7.15x7.15 mm sup 2 with magnifications from 4x to 40x. With the highest magnification 480 lp/mm had been achieved at 10% modulation transfer function which corresponds to a spatial resolution of 1.04 mu m. A low-noise fast-readout CCD camera transfers 2048x2048 pixels within 100-250 ms at a dynamic range of 12-14 bit to the file server. A user-friendly graphical interface gives access to the main parameters needed for ...

  9. Skull x-ray

    Science.gov (United States)

    X-ray - head; X-ray - skull; Skull radiography; Head x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

  10. Neck x-ray

    Science.gov (United States)

    X-ray - neck; Cervical spine x-ray; Lateral neck x-ray ... There is low radiation exposure. X-rays are monitored so that the lowest amount of radiation is used to produce the image. Pregnant women and ...

  11. A novel lobster-eye imaging system based on Schmidt-type objective for X-ray-backscattering inspection

    International Nuclear Information System (INIS)

    Xu, Jie; Wang, Xin; Zhan, Qi; Huang, Shengling; Chen, Yifan; Mu, Baozhong

    2016-01-01

    This paper presents a novel lobster-eye imaging system for X-ray-backscattering inspection. The system was designed by modifying the Schmidt geometry into a treble-lens structure in order to reduce the resolution difference between the vertical and horizontal directions, as indicated by ray-tracing simulations. The lobster-eye X-ray imaging system is capable of operating over a wide range of photon energies up to 100 keV. In addition, the optics of the lobster-eye X-ray imaging system was tested to verify that they meet the requirements. X-ray-backscattering imaging experiments were performed in which T-shaped polymethyl-methacrylate objects were imaged by the lobster-eye X-ray imaging system based on both the double-lens and treble-lens Schmidt objectives. The results show similar resolution of the treble-lens Schmidt objective in both the vertical and horizontal directions. Moreover, imaging experiments were performed using a second treble-lens Schmidt objective with higher resolution. The results show that for a field of view of over 200 mm and with a 500 mm object distance, this lobster-eye X-ray imaging system based on a treble-lens Schmidt objective offers a spatial resolution of approximately 3 mm.

  12. From synchrotron radiation to lab source: advanced speckle-based X-ray imaging using abrasive paper

    Science.gov (United States)

    Wang, Hongchang; Kashyap, Yogesh; Sawhney, Kawal

    2016-02-01

    X-ray phase and dark-field imaging techniques provide complementary and inaccessible information compared to conventional X-ray absorption or visible light imaging. However, such methods typically require sophisticated experimental apparatus or X-ray beams with specific properties. Recently, an X-ray speckle-based technique has shown great potential for X-ray phase and dark-field imaging using a simple experimental arrangement. However, it still suffers from either poor resolution or the time consuming process of collecting a large number of images. To overcome these limitations, in this report we demonstrate that absorption, dark-field, phase contrast, and two orthogonal differential phase contrast images can simultaneously be generated by scanning a piece of abrasive paper in only one direction. We propose a novel theoretical approach to quantitatively extract the above five images by utilising the remarkable properties of speckles. Importantly, the technique has been extended from a synchrotron light source to utilise a lab-based microfocus X-ray source and flat panel detector. Removing the need to raster the optics in two directions significantly reduces the acquisition time and absorbed dose, which can be of vital importance for many biological samples. This new imaging method could potentially provide a breakthrough for numerous practical imaging applications in biomedical research and materials science.

  13. Simulating and optimizing compound refractive lens-based X-ray microscopes

    DEFF Research Database (Denmark)

    Simons, Hugh; Ahl, Sonja Rosenlund; Poulsen, Henning Friis

    2017-01-01

    A comprehensive optical description of compound refractive lenses (CRLs) in condensing and full-field X-ray microscopy applications is presented. The formalism extends ray-transfer matrix analysis by accounting for X-ray attenuation by the lens material. Closed analytical expressions for critical......-lens limit. This limit may be satisfied by a range of CRL geometries, suggesting alternative approaches to improving the resolution and efficiency of CRLs and X-ray microscopes....

  14. A VXI-based high speed x-ray CCD detector

    International Nuclear Information System (INIS)

    Huang, Qiang; Hopf, R.; Rodricks, B.

    1993-01-01

    For time-resolved x-ray scattering, one ideally wants a high speed detector that also is capable of giving position sensitive information. Charge Coupled Devices (CCDS) have been used successfully as x-ray detectors. Unfortunately, they are inherently slow because of the serial readout EEV has developed a CCD that has eight channels of parallel readout, thus increasing the speed eight fold. Using state-of-the-art VXI electronics, we have developed a readout system that could read the entire array in 2.5 ms using a 20-MHz readout clock. For testing and characterization the device was clocked at a significantly slower speed of 30 kHz. The data is preamplified and all eight channels of output are simultaneously digitized to 12 bits and stored in buffer memory. The system is controlled by a 486-based PC through an MXI bus and VXI controller using commercially available software. The system is also capable of real-time image display and manipulation

  15. Interior Temperature Measurement Using Curved Mercury Capillary Sensor Based on X-ray Radiography

    Science.gov (United States)

    Chen, Shuyue; Jiang, Xing; Lu, Guirong

    2017-07-01

    A method was presented for measuring the interior temperature of objects using a curved mercury capillary sensor based on X-ray radiography. The sensor is composed of a mercury bubble, a capillary and a fixed support. X-ray digital radiography was employed to capture image of the mercury column in the capillary, and a temperature control system was designed for the sensor calibration. We adopted livewire algorithms and mathematical morphology to calculate the mercury length. A measurement model relating mercury length to temperature was established, and the measurement uncertainty associated with the mercury column length and the linear model fitted by least-square method were analyzed. To verify the system, the interior temperature measurement of an autoclave, which is totally closed, was taken from 29.53°C to 67.34°C. The experiment results show that the response of the system is approximately linear with an uncertainty of maximum 0.79°C. This technique provides a new approach to measure interior temperature of objects.

  16. An X-ray imager based on silicon microstrip detector and coded mask

    International Nuclear Information System (INIS)

    Del Monte, E.; Costa, E.; Di Persio, G.; Donnarumma, I.; Evangelista, Y.; Feroci, M.; Frutti, M.; Lapshov, I.; Lazzarotto, F.; Mastropietro, M.; Morelli, E.; Pacciani, L.; Porrovecchio, G.; Rapisarda, M.; Rubini, A.; Soffitta, P.; Tavani, M.; Argan, A.

    2007-01-01

    SuperAGILE is the X-ray monitor of AGILE, a satellite mission for gamma-ray astronomy, and it is the first X-ray imaging instrument based on the technology of the silicon microstrip detectors combined with a coded aperture imaging technique. The SuperAGILE detection plane is composed of four 1-D silicon microstrip detector modules, mechanically coupled to tungsten coded mask units. The detector strips are separately and individually connected to the input analogue channels of the front-end electronics, composed of low-noise and low-power consumption VLSI ASIC chips. SuperAGILE can produce 1-D images with 6 arcmin angular resolution and ∼2-3 arcmin localisation capability, for intense sources, in a field of view composed of two orthogonal areas of 107 deg. x 68 deg. The time resolution is 2 μs, the overall dead time is ∼5 μs and the electronic noise is ∼7.5 keV full-width at half-maximum. The resulting instrument is very compact (40x40x14 cm 3 ), light (10 kg) and has low power consumption (12 W). AGILE is a mission of the Agenzia Spaziale Italiana and its launch is planned in 2007 in a low equatorial Earth orbit. In this contribution we present SuperAGILE and discuss its performance and scientific objectives

  17. Improvement of an X-ray imaging detector based on a scintillating guides screen

    CERN Document Server

    Badel, X; Linnros, J; Kleimann, P; Froejdh, C; Petersson, C S

    2002-01-01

    An X-ray imaging detector has been developed for dental applications. The principle of this detector is based on application of a silicon charge coupled device covered by a scintillating wave-guide screen. Previous studies of such a detector showed promising results concerning the spatial resolution but low performance in terms of signal to noise ratio (SNR) and sensitivity. Recent results confirm the wave-guiding properties of the matrix and show improvement of the detector in terms of response uniformity, sensitivity and SNR. The present study is focussed on the fabrication of the scintillating screen where the principal idea is to fill a matrix of Si pores with a CsI scintillator. The photoluminescence technique was used to prove the wave-guiding property of the matrix and to inspect the filling uniformity of the pores. The final detector was characterized by X-ray evaluation in terms of spatial resolution, light output and SNR. A sensor with a spatial resolution of 9 LP/mm and a SNR over 50 has been achie...

  18. Visualization of ultrasound induced cavitation bubbles using the synchrotron x-ray Analyzer Based Imaging technique

    International Nuclear Information System (INIS)

    Izadifar, Zahra; Izadifar, Mohammad; Izadifar, Zohreh; Chapman, Dean; Belev, George

    2014-01-01

    Observing cavitation bubbles deep within tissue is very difficult. The development of a method for probing cavitation, irrespective of its location in tissues, would improve the efficiency and application of ultrasound in the clinic. A synchrotron x-ray imaging technique, which is capable of detecting cavitation bubbles induced in water by a sonochemistry system, is reported here; this could possibly be extended to the study of therapeutic ultrasound in tissues. The two different x-ray imaging techniques of Analyzer Based Imaging (ABI) and phase contrast imaging (PCI) were examined in order to detect ultrasound induced cavitation bubbles. Cavitation was not observed by PCI, however it was detectable with ABI. Acoustic cavitation was imaged at six different acoustic power levels and six different locations through the acoustic beam in water at a fixed power level. The results indicate the potential utility of this technique for cavitation studies in tissues, but it is time consuming. This may be improved by optimizing the imaging method. (paper)

  19. Visualization of ultrasound induced cavitation bubbles using the synchrotron x-ray Analyzer Based Imaging technique.

    Science.gov (United States)

    Izadifar, Zahra; Belev, George; Izadifar, Mohammad; Izadifar, Zohreh; Chapman, Dean

    2014-12-07

    Observing cavitation bubbles deep within tissue is very difficult. The development of a method for probing cavitation, irrespective of its location in tissues, would improve the efficiency and application of ultrasound in the clinic. A synchrotron x-ray imaging technique, which is capable of detecting cavitation bubbles induced in water by a sonochemistry system, is reported here; this could possibly be extended to the study of therapeutic ultrasound in tissues. The two different x-ray imaging techniques of Analyzer Based Imaging (ABI) and phase contrast imaging (PCI) were examined in order to detect ultrasound induced cavitation bubbles. Cavitation was not observed by PCI, however it was detectable with ABI. Acoustic cavitation was imaged at six different acoustic power levels and six different locations through the acoustic beam in water at a fixed power level. The results indicate the potential utility of this technique for cavitation studies in tissues, but it is time consuming. This may be improved by optimizing the imaging method.

  20. Speckle-based portable device for in-situ metrology of x-ray mirrors at Diamond Light Source

    Science.gov (United States)

    Wang, Hongchang; Kashyap, Yogesh; Zhou, Tunhe; Sawhney, Kawal

    2017-09-01

    For modern synchrotron light sources, the push toward diffraction-limited and coherence-preserved beams demands accurate metrology on X-ray optics. Moreover, it is important to perform in-situ characterization and optimization of X-ray mirrors since their ultimate performance is critically dependent on the working conditions. Therefore, it is highly desirable to develop a portable metrology device, which can be easily implemented on a range of beamlines for in-situ metrology. An X-ray speckle-based portable device for in-situ metrology of synchrotron X-ray mirrors has been developed at Diamond Light Source. Ultra-high angular sensitivity is achieved by scanning the speckle generator in the X-ray beam. In addition to the compact setup and ease of implementation, a user-friendly graphical user interface has been developed to ensure that characterization and alignment of X-ray mirrors is simple and fast. The functionality and feasibility of this device is presented with representative examples.

  1. 3d Finite Element Modelling of Non-Crimp Fabric Based Fibre Composite Based on X-Ray Ct Data

    DEFF Research Database (Denmark)

    Jespersen, Kristine Munk; Asp, Leif; Mikkelsen, Lars Pilgaard

    2017-01-01

    initiation and progression in the material. In the current study, the real bundle structure inside a non-crimp fabric based fibre composite is extracted from 3D X-ray CT images and imported into ABAQUS for numerical modelling.The local stress concentrations when loaded in tension caused by the fibre bundle...

  2. Fast GPU-based spot extraction for energy-dispersive X-ray Laue diffraction

    International Nuclear Information System (INIS)

    Alghabi, F.; Schipper, U.; Kolb, A.; Send, S.; Abboud, A.; Pashniak, N.; Pietsch, U.

    2014-01-01

    This paper describes a novel method for fast online analysis of X-ray Laue spots taken by means of an energy-dispersive X-ray 2D detector. Current pnCCD detectors typically operate at some 100 Hz (up to a maximum of 400 Hz) and have a resolution of 384 × 384 pixels, future devices head for even higher pixel counts and frame rates. The proposed online data analysis is based on a computer utilizing multiple Graphics Processing Units (GPUs), which allow for fast and parallel data processing. Our multi-GPU based algorithm is compliant with the rules of stream-based data processing, for which GPUs are optimized. The paper's main contribution is therefore an alternative algorithm for the determination of spot positions and energies over the full sequence of pnCCD data frames. Furthermore, an improved background suppression algorithm is presented.The resulting system is able to process data at the maximum acquisition rate of 400 Hz. We present a detailed analysis of the spot positions and energies deduced from a prior (single-core) CPU-based and the novel GPU-based data processing, showing that the parallel computed results using the GPU implementation are at least of the same quality as prior CPU-based results. Furthermore, the GPU-based algorithm is able to speed up the data processing by a factor of 7 (in comparison to single-core CPU-based algorithm) which effectively makes the detector system more suitable for online data processing

  3. Spline based iterative phase retrieval algorithm for X-ray differential phase contrast radiography.

    Science.gov (United States)

    Nilchian, Masih; Wang, Zhentian; Thuering, Thomas; Unser, Michael; Stampanoni, Marco

    2015-04-20

    Differential phase contrast imaging using grating interferometer is a promising alternative to conventional X-ray radiographic methods. It provides the absorption, differential phase and scattering information of the underlying sample simultaneously. Phase retrieval from the differential phase signal is an essential problem for quantitative analysis in medical imaging. In this paper, we formalize the phase retrieval as a regularized inverse problem, and propose a novel discretization scheme for the derivative operator based on B-spline calculus. The inverse problem is then solved by a constrained regularized weighted-norm algorithm (CRWN) which adopts the properties of B-spline and ensures a fast implementation. The method is evaluated with a tomographic dataset and differential phase contrast mammography data. We demonstrate that the proposed method is able to produce phase image with enhanced and higher soft tissue contrast compared to conventional absorption-based approach, which can potentially provide useful information to mammographic investigations.

  4. The design of portable X-ray fluorescence analyzer based on PDA

    International Nuclear Information System (INIS)

    Zhou Jianbin; Ma Yingjie; Wang Lei; Tong Yunfu

    2010-01-01

    It designs a portable x-ray fluorescence analyzer based on PDA. The high performance Single Chip Microcomputer-C8051F060 works as the core controller on the measure-control board. The communication between PDA and measure-control board is based on Bluetooth technology. Benefiting from the rich resource on the chip of C8051F060, it's very easy to design the MCA (Multi-Channel Analyzer), detection-control circuit, peak-detection circuit compactly. WinCE OS runs on the PDA, and the analysis software is designed on the Visual Studio2005 in C++. The power of the system is supplied by the lithium battery. (authors)

  5. X-ray diffraction of slag-based sodium salt waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Missimer, D. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-09-30

    The attached report documents sample preparation and x-ray diffraction results for a series of cement and blended cement matrices prepared with either water or a 4.4 M Na salt solution. The objective of the study was to provide initial phase characterization for the Cementitious Barriers Partnership reference case cementitious salt waste form. This information can be used to: 1) generate a base line for the evolution of the waste form as a function of time and conditions, 2) potentially to design new binders based on mineralogy of the binder, 3) understand and predict anion and cation leaching behavior of contaminants of concern, and 4) predict performance of the waste forms for which phase solubility and thermodynamic data are available.

  6. Synthesis, X-ray crystallography, thermal studies, spectroscopic and electrochemistry investigations of uranyl Schiff base complexes.

    Science.gov (United States)

    Asadi, Zahra; Shorkaei, Mohammad Ranjkesh

    2013-03-15

    Some tetradentate salen type Schiff bases and their uranyl complexes were synthesized and characterized by UV-Vis, NMR, IR, TG, C.H.N. and X-ray crystallographic studies. From these investigations it is confirmed that a solvent molecule occupied the fifth position of the equatorial plane of the distorted pentagonal bipyramidal structure. Also, the kinetics of complex decomposition by using thermo gravimetric methods (TG) was studied. The thermal decomposition reactions are first order for the studied complexes. To examine the properties of uranyl complexes according to the substitutional groups, we have carried out the electrochemical studies. The electrochemical reactions of uranyl Schiff base complexes in acetonitrile were reversible. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Using acoustic levitation in synchrotron based laser pump hard x-ray probe experiments

    Science.gov (United States)

    Hu, Bin; Lerch, Jason; Suthar, Kamlesh; Dichiara, Anthony

    Acoustic levitation provides a platform to trap and hold a small amount of material by using standing pressure waves without a container. The technique has a potential to be used for laser pump x-ray probe experiments; x-ray scattering and laser distortion from the container can be avoided, sample consumption can be minimized, and unwanted chemistry that may occur at the container interface can be avoided. The method has been used at synchrotron sources for studying protein and pharmaceutical solutions using x-ray diffraction (XRD) and small angle x-ray scattering (SAXS). However, pump-probe experiments require homogeneously excited samples, smaller than the absorption depth of the material that must be held stably at the intersection of both the laser and x-ray beams. We discuss 1) the role of oscillations in acoustic levitation and the optimal acoustic trapping conditions for x-ray/laser experiments, 2) opportunities to automate acoustic levitation for fast sample loading and manipulation, and 3) our experimental results using SAXS to monitor laser induced thermal expansion in gold nanoparticles solution. We also performed Finite Element Analysis to optimize the trapping performance and stability of droplets ranging from 0.4 mm to 2 mm. Our early x-ray/laser demonstrated the potential of the technique for time-resolved X-ray science.

  8. Impact of intense x-ray pulses on a NaI(Tl)-based gamma camera

    NARCIS (Netherlands)

    Koppert, Wilco J C; van der Velden, Sandra; Steenbergen, J H Leo; de Jong, Hugo W A M

    2018-01-01

    INTRODUCTION: In SPECT/CT systems X-ray and -ray imaging is performed sequentially. Simultaneous acquisition may have advantages, for instance in interventional settings. However, this may expose a gamma camera to relatively high X-ray doses and deteriorate its functioning. We studied the NaI(Tl)

  9. An MCNP-based model of a medical linear accelerator x-ray photon beam.

    Science.gov (United States)

    Ajaj, F A; Ghassal, N M

    2003-09-01

    The major components in the x-ray photon beam path of the treatment head of the VARIAN Clinac 2300 EX medical linear accelerator were modeled and simulated using the Monte Carlo N-Particle radiation transport computer code (MCNP). Simulated components include x-ray target, primary conical collimator, x-ray beam flattening filter and secondary collimators. X-ray photon energy spectra and angular distributions were calculated using the model. The x-ray beam emerging from the secondary collimators were scored by considering the total x-ray spectra from the target as the source of x-rays at the target position. The depth dose distribution and dose profiles at different depths and field sizes have been calculated at a nominal operating potential of 6 MV and found to be within acceptable limits. It is concluded that accurate specification of the component dimensions, composition and nominal accelerating potential gives a good assessment of the x-ray energy spectra.

  10. Portable pulsed X-ray digital radiographic system based on network transmission

    International Nuclear Information System (INIS)

    Tang Le; Li Yuanjing; Wang Yi; Cheng Jianping

    2004-01-01

    Network communication technology of TCP/IP protocol serves as application in pulse X-ray digital radiography system. The system radiographs synchronously with pulse X-ray and converts image signals to digital data, which are transmitted to computer for displaying and processing in network. The system composing structures are present and portable and other characteristics are introduced. (authors)

  11. Iron overload of human colon adenocarcinoma cells studied by synchrotron-based X-ray techniques

    NARCIS (Netherlands)

    Mihucz, Victor G.; Meirer, Florian; Polgári, Zsófia; Réti, Andrea; Pepponi, Giancarlo; Ingerle, Dieter; Szoboszlai, Norbert; Streli, Christina

    2016-01-01

    Fast- and slow-proliferating human adenocarcinoma colorectal cells, HT-29 and HCA-7, respectively, overloaded with transferrin (Tf), Fe(III) citrate, Fe(III) chloride and Fe(II) sulfate were studied by synchrotron radiation total-reflection X-ray spectrometry (TXRF), TXRF-X-ray absorption near edge

  12. Impact of intense x-ray pulses on a NaI(Tl)-based gamma camera

    Science.gov (United States)

    Koppert, W. J. C.; van der Velden, S.; Steenbergen, J. H. L.; de Jong, H. W. A. M.

    2018-03-01

    In SPECT/CT systems x-ray and γ-ray imaging is performed sequentially. Simultaneous acquisition may have advantages, for instance in interventional settings. However, this may expose a gamma camera to relatively high x-ray doses and deteriorate its functioning. We studied the NaI(Tl) response to x-ray pulses with a photodiode, PMT and gamma camera, respectively. First, we exposed a NaI(Tl)-photodiode assembly to x-ray pulses to investigate potential crystal afterglow. Next, we exposed a NaI(Tl)-PMT assembly to 10 ms LED pulses (mimicking x-ray pulses) and measured the response to flashing LED probe-pulses (mimicking γ-pulses). We then exposed the assembly to x-ray pulses, with detector entrance doses of up to 9 nGy/pulse, and analysed the response for γ-pulse variations. Finally, we studied the response of a Siemens Diacam gamma camera to γ-rays while exposed to x-ray pulses. X-ray exposure of the crystal, read out with a photodiode, revealed 15% afterglow fraction after 3 ms. The NaI(Tl)-PMT assembly showed disturbances up to 10 ms after 10 ms LED exposure. After x-ray exposure however, responses showed elevated baselines, with 60 ms decay-time. Both for x-ray and LED exposure and after baseline subtraction, probe-pulse analysis revealed disturbed pulse height measurements shortly after exposure. X-ray exposure of the Diacam corroborated the elementary experiments. Up to 50 ms after an x-ray pulse, no events are registered, followed by apparent energy elevations up to 100 ms after exposure. Limiting the dose to 0.02 nGy/pulse prevents detrimental effects. Conventional gamma cameras exhibit substantial dead-time and mis-registration of photon energies up to 100 ms after intense x-ray pulses. This is due PMT limitations and due to afterglow in the crystal. Using PMTs with modified circuitry, we show that deteriorative afterglow effects can be reduced without noticeable effects on the PMT performance, up to x-ray pulse doses of 1 nGy.

  13. Mammographic x-ray unit kilovoltage test tool based on k-edge absorption effect.

    Science.gov (United States)

    Napolitano, Mary E; Trueblood, Jon H; Hertel, Nolan E; David, George

    2002-09-01

    A simple tool to determine the peak kilovoltage (kVp) of a mammographic x-ray unit has been designed. Tool design is based on comparing the effect of k-edge discontinuity of the attenuation coefficient for a series of element filters. Compatibility with the mammography accreditation phantom (MAP) to obtain a single quality control film is a second design objective. When the attenuation of a series of sequential elements is studied simultaneously, differences in the absorption characteristics due to the k-edge discontinuities are more evident. Specifically, when the incident photon energy is higher than the k-edge energy of a number of the elements and lower than the remainder, an inflection may be seen in the resulting attenuation data. The maximum energy of the incident photon spectra may be determined based on this inflection point for a series of element filters. Monte Carlo photon transport analysis was used to estimate the photon transmission probabilities for each of the sequential k-edge filter elements. The photon transmission corresponds directly to optical density recorded on mammographic x-ray film. To observe the inflection, the element filters chosen must have k-edge energies that span a range greater than the expected range of the end point energies to be determined. For the design, incident x-ray spectra ranging from 25 to 40 kVp were assumed to be from a molybdenum target. Over this range, the k-edge energy changes by approximately 1.5 keV between sequential elements. For this design 21 elements spanning an energy range from 20 to 50 keV were chosen. Optimum filter element thicknesses were calculated to maximize attenuation differences at the k-edge while maintaining optical densities between 0.10 and 3.00. Calculated relative transmission data show that the kVp could be determined to within +/-1 kV. To obtain experimental data, a phantom was constructed containing 21 different elements placed in an acrylic holder. MAP images were used to determine

  14. Mammographic x-ray unit kilovoltage test tool based on k-edge absorption effect

    International Nuclear Information System (INIS)

    Napolitano, Mary E.; Trueblood, Jon H.; Hertel, Nolan E.; David, George

    2002-01-01

    A simple tool to determine the peak kilovoltage (kVp) of a mammographic x-ray unit has been designed. Tool design is based on comparing the effect of k-edge discontinuity of the attenuation coefficient for a series of element filters. Compatibility with the mammography accreditation phantom (MAP) to obtain a single quality control film is a second design objective. When the attenuation of a series of sequential elements is studied simultaneously, differences in the absorption characteristics due to the k-edge discontinuities are more evident. Specifically, when the incident photon energy is higher than the k-edge energy of a number of the elements and lower than the remainder, an inflection may be seen in the resulting attenuation data. The maximum energy of the incident photon spectra may be determined based on this inflection point for a series of element filters. Monte Carlo photon transport analysis was used to estimate the photon transmission probabilities for each of the sequential k-edge filter elements. The photon transmission corresponds directly to optical density recorded on mammographic x-ray film. To observe the inflection, the element filters chosen must have k-edge energies that span a range greater than the expected range of the end point energies to be determined. For the design, incident x-ray spectra ranging from 25 to 40 kVp were assumed to be from a molybdenum target. Over this range, the k-edge energy changes by approximately 1.5 keV between sequential elements. For this design 21 elements spanning an energy range from 20 to 50 keV were chosen. Optimum filter element thicknesses were calculated to maximize attenuation differences at the k-edge while maintaining optical densities between 0.10 and 3.00. Calculated relative transmission data show that the kVp could be determined to within ±1 kV. To obtain experimental data, a phantom was constructed containing 21 different elements placed in an acrylic holder. MAP images were used to determine

  15. A software-based x-ray scatter correction method for breast tomosynthesis

    International Nuclear Information System (INIS)

    Jia Feng, Steve Si; Sechopoulos, Ioannis

    2011-01-01

    Purpose: To develop a software-based scatter correction method for digital breast tomosynthesis (DBT) imaging and investigate its impact on the image quality of tomosynthesis reconstructions of both phantoms and patients. Methods: A Monte Carlo (MC) simulation of x-ray scatter, with geometry matching that of the cranio-caudal (CC) view of a DBT clinical prototype, was developed using the Geant4 toolkit and used to generate maps of the scatter-to-primary ratio (SPR) of a number of homogeneous standard-shaped breasts of varying sizes. Dimension-matched SPR maps were then deformed and registered to DBT acquisition projections, allowing for the estimation of the primary x-ray signal acquired by the imaging system. Noise filtering of the estimated projections was then performed to reduce the impact of the quantum noise of the x-ray scatter. Three dimensional (3D) reconstruction was then performed using the maximum likelihood-expectation maximization (MLEM) method. This process was tested on acquisitions of a heterogeneous 50/50 adipose/glandular tomosynthesis phantom with embedded masses, fibers, and microcalcifications and on acquisitions of patients. The image quality of the reconstructions of the scatter-corrected and uncorrected projections was analyzed by studying the signal-difference-to-noise ratio (SDNR), the integral of the signal in each mass lesion (integrated mass signal, IMS), and the modulation transfer function (MTF). Results: The reconstructions of the scatter-corrected projections demonstrated superior image quality. The SDNR of masses embedded in a 5 cm thick tomosynthesis phantom improved 60%-66%, while the SDNR of the smallest mass in an 8 cm thick phantom improved by 59% (p < 0.01). The IMS of the masses in the 5 cm thick phantom also improved by 15%-29%, while the IMS of the masses in the 8 cm thick phantom improved by 26%-62% (p < 0.01). Some embedded microcalcifications in the tomosynthesis phantoms were visible only in the scatter

  16. A filter based analyzer for studies of X-ray Raman scattering

    CERN Document Server

    Seidler, G T

    2001-01-01

    Non-resonant X-ray Raman scattering (XRS) with hard X-rays holds the potential for measuring local structure and local electronic properties around low-Z atoms in environments where traditional soft X-ray techniques are inapplicable. However, the small cross-section for XRS requires that experiments must simultaneously achieve high detection efficiency, large collection solid angles, and good energy resolution. We report here that a simple X-ray analyzer consisting of an absorber and a point-focusing spatial filter can be used to study some X-ray Raman near-edge features. This apparatus has greater than 10% detection efficiency, has an energy resolution of 8 eV, and can be readily extended to collection angles of more than 1 sr. We present preliminary measurements of the XRS from the nitrogen 1 s shell in pyrolitic boron nitride.

  17. S-band linac-based X-ray source with {pi}/2-mode electron linac

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, Abhay, E-mail: abhay@post.kek.jp [Department of Accelerator Science, School of High Energy Accelerator Science, Graduate University for Advanced Studies, Shonan International Village, Hayama, Miura, Kanagawa 240-0193 (Japan); Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Araki, Sakae [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Dixit, Tanuja [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Fukuda, Masafumi [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Krishnan, R; Pethe, Sanjay [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Sakaue, Kazuyuki [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan); Terunuma, Nobuhiro; Urakawa, Junji [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Washio, Masakazu [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2011-05-01

    The activities with the compact X-ray source are attracting more attention, particularly for the applications of the source in medical fields. We propose the fabrication of a compact X-ray source using the SAMEER electron linear accelerator and the KEK laser undulator X-ray source (LUCX) technologies. The linac developed at SAMEER is a standing wave side-coupled S-band linac operating in the {pi}/2 mode. In the proposed system, a photocathode RF gun will inject bunches of electrons in the linac to accelerate and achieve a high-energy, low-emittance beam. This beam will then interact with the laser in the laser cavity to produce X-rays of a type well suited for various applications. The side-coupled structure will make the system more compact, and the {pi}/2 mode of operation will enable a high repetition rate operation, which will help to increase the X-ray yield.

  18. Laboratory-based recording of holographic fine structure in X-ray absorption anisotropy using polycapillary optics

    Energy Technology Data Exchange (ETDEWEB)

    Dabrowski, K.M. [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland); Korecki, P., E-mail: pawel.korecki@uj.edu.pl [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Holographic fine structures in X-ray absorption recorded using a tabletop setup. Black-Right-Pointing-Pointer Setup based on polycapillary collimating optics and an HOPG crystal. Black-Right-Pointing-Pointer Demonstration of element sensitivity by detection of X-ray fluorescence. Black-Right-Pointing-Pointer Potential of laboratory-based experiments for heavily doped crystals and thin films. - Abstract: A tabletop setup composed of a collimating polycapillary optics and a highly oriented pyrolytic graphite monochromator (HOPG) was characterized and used for recording two-dimensional maps of X-ray absorption anisotropy (XAA). XAA originates from interference of X-rays directly inside the sample. Depending on experimental conditions, fine structures in XAA can be interpreted in terms of X-ray holograms or X-ray standing waves and can be used for an element selective atomic-resolved structural analysis. The implementation of polycapillary optics resulted in a two-order of magnitude gain in the radiant intensity (photons/s/solid angle) as compared to a system without optics and enabled efficient recording of XAA with a resolution of 0.15 Degree-Sign for Mo K{alpha} radiation. Element sensitivity was demonstrated by acquisition of distinct XAA signals for Ga and As atoms in a GaAs (1 1 1) wafer by using X-ray fluorescence as a secondary signal. These results indicate the possibility of performing laboratory-based XAA experiments for heavily doped single crystals or thin films. So far, because of the weak holographic modulation of XAA, such experiments could be only performed using synchrotron radiation.

  19. Design and development of AXUV-based soft X-ray diagnostic camera for Aditya Tokamak

    International Nuclear Information System (INIS)

    Raval, Jayesh V.; Purohit, Shishir; Joisa, Y. Shankara

    2015-01-01

    The hot tokamak plasma emits Soft X-rays (SXR) in accordance with the temperature and density which are important to be studied. A silicon photo diode array (AXUV16ELG, Opto-diode, USA) based prototype SXR diagnostics is designed and developed for ADITYA tokamak for the study of SXR radial intensity profile, internal disruption (Saw-tooth crash), MHD instabilities. The diagnostic is having an array of 16 detector of millimeter dimension in a linear configuration. Absolute Extreme Ultra Violate (AXUV) detector offers compact size, improved time response with considerably good quantum efficiency in the soft X-ray range (200 eV to 10 keV). The diagnostic is designed in competence with the ADITYA tokamak protocol. The diagnostic design geometry allows detector view the plasma through a slot hole (0.5 cm X 0.05 cm), 10 μm Beryllium foil filter window, cutting off energies below 750 eV. The diagnostic was installed on Aditya vacuum vessel at radial port no 7 enabling the diagnostics to view the core plasma. The spatial resolution designed for diagnostic configuration is 1.3 cm at plasma centre. The signal generated from SXR detector is acquired with a dedicated single board computer based data acquisition system at 50 kHz. The diagnostic took observation for the ohmically heated plasma. The data was then processed to construct spatial and temporal profile of SXR intensity for Aditya plasma. This information was complimentary to the Silicon surface barrier detector (SBD) based array for the same plasma discharge. The cross calibration between the two was considerably satisfactory under the assumptions considered. (author)

  20. Study of Inverse Ni-based Photonic Crystal using the Microradian X-ray Diffraction

    Science.gov (United States)

    Vasilieva, A. V.; Grigoryeva, N. A.; Mistonov, A. A.; Sapoletova, N. A.; Napolskii, K. S.; Eliseev, A. A.; Lukashin, A. V.; Tretyakov, Yu D.; Petukhov, A. V.; Byelov, D.; Chernyshov, D.; Okorokov, A. I.; Bouwman, W. G.; Grigoriev, S. V.

    2010-10-01

    Inverse photonic nickel-based crystal films formed by electrocrystallization of metal inside the voids of polymer artificial opal have been studied using the microradian X-ray diffraction. Analysis of the diffraction images agrees with an face-centred cubic (FCC) structure with the lattice constant a0 = 650 ± 10 nm and indicates two types of stacking sequences coexisting in the crystal (twins of ABCABC... and ACBACB... ordering motifs), the ratio between them being 4:5 The transverse structural correlation length Ltran is 2.4 ± 0.1 μm, which corresponds to a sample thickness of 6 layers. The in-plane structural correlation length Llong is 3.4 ± 0.2 μm, and the structure mosaic is of order of 10°.

  1. Study of Inverse Ni-based Photonic Crystal using the Microradian X-ray Diffraction

    International Nuclear Information System (INIS)

    Vasilieva, A V; Okorokov, A I; Grigoriev, S V; Grigoryeva, N A; Mistonov, A A; Sapoletova, N A; Napolskii, K S; Eliseev, A A; Lukashin, A V; Tretyakov, Yu D; Petukhov, A V; Byelov, D; Chernyshov, D; Bouwman, W G

    2010-01-01

    Inverse photonic nickel-based crystal films formed by electrocrystallization of metal inside the voids of polymer artificial opal have been studied using the microradian X-ray diffraction. Analysis of the diffraction images agrees with an face-centred cubic (FCC) structure with the lattice constant a 0 = 650 ± 10 nm and indicates two types of stacking sequences coexisting in the crystal (twins of ABCABC... and ACBACB... ordering motifs), the ratio between them being 4:5 The transverse structural correlation length L tran is 2.4 ± 0.1 μm, which corresponds to a sample thickness of 6 layers. The in-plane structural correlation length L long is 3.4 ± 0.2 μm, and the structure mosaic is of order of 10 0 .

  2. Study of Inverse Ni-based Photonic Crystal using the Microradian X-ray Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Vasilieva, A V; Okorokov, A I; Grigoriev, S V [Petersburg Nuclear Physics Institute, Gatchina, 188350, St. Petersburg (Russian Federation); Grigoryeva, N A; Mistonov, A A [Department of Physics, St. Petersburg State University, 198504, St. Petersburg (Russian Federation); Sapoletova, N A; Napolskii, K S; Eliseev, A A; Lukashin, A V; Tretyakov, Yu D [Department of Materials Science, Moscow State University, 119899, Moscow (Russian Federation); Petukhov, A V; Byelov, D [Debye Institute, Utrecht University, 3584 CH Utrecht (Netherlands); Chernyshov, D [SNBL European Synchrotron Radiation Facility (ESRF), 38043 Grenoble (France); Bouwman, W G, E-mail: vasilieva@lns.pnpi.spb.r [Delft Technical University, 2629 JB Delft (Netherlands)

    2010-10-01

    Inverse photonic nickel-based crystal films formed by electrocrystallization of metal inside the voids of polymer artificial opal have been studied using the microradian X-ray diffraction. Analysis of the diffraction images agrees with an face-centred cubic (FCC) structure with the lattice constant a{sub 0} = 650 {+-} 10 nm and indicates two types of stacking sequences coexisting in the crystal (twins of ABCABC... and ACBACB... ordering motifs), the ratio between them being 4:5 The transverse structural correlation length L{sub tran} is 2.4 {+-} 0.1 {mu}m, which corresponds to a sample thickness of 6 layers. The in-plane structural correlation length L{sub long} is 3.4 {+-} 0.2 {mu}m, and the structure mosaic is of order of 10{sup 0}.

  3. A fundamental parameter-based calibration model for an intrinsic germanium X-ray fluorescence spectrometer

    International Nuclear Information System (INIS)

    Christensen, L.H.; Pind, N.

    1982-01-01

    A matrix-independent fundamental parameter-based calibration model for an energy-dispersive X-ray fluorescence spectrometer has been developed. This model, which is part of a fundamental parameter approach quantification method, accounts for both the excitation and detection probability. For each secondary target a number of relative calibration constants are calculated on the basis of knowledge of the irradiation geometry, the detector specifications, and tabulated fundamental physical parameters. The absolute calibration of the spectrometer is performed by measuring one pure element standard per secondary target. For sample systems where all elements can be analyzed by means of the same secondary target the absolute calibration constant can be determined during the iterative solution of the basic equation. Calculated and experimentally determined relative calibration constants agree to within 5-10% of each other and so do the results obtained from the analysis of an NBS certified alloy using the two sets of constants. (orig.)

  4. Hard x-ray microimaging techniques based on phase zone plates

    International Nuclear Information System (INIS)

    Lai, B.; Yun, W.B.; Legnini, D.; Xiao, Y.H.; Chrzas, J.

    1992-01-01

    Phase zone plates of high focusing efficiency and submicron resolution have been demonstrated in the hard x-ray region. A scanning microscope based on these focusing optics will create many new applications. Preliminary results in the applications of the microscope are reported here. In the area of imaging, we have utilized absorption contrast to clearly identify the locations of Au and Ni constituents in a sample of two interleaved grids. Micro-EXAFS spectra has also been obtained on a Ni foil. Fluorescence from a nuclear fuel sample, as an example of microanalysis, has revealed the elemental distribution at the interfaces. Lastly, microdiffraction from AgBr crystallites has been studied. 5 figs, 7 refs

  5. The application and development of radiography technology based on x-ray

    Science.gov (United States)

    Chen, Hao; Xu, Zhou; Li, Ming

    2009-07-01

    Modern Radiography technology was combined with radiation physics and modern imaging processing, which was an important branch of information obtainment and processing. We can get the inside information of the object, by the X ray's attenuation when the ray penetrated the object, and depending on the computer's fast processing, we can see the slice imaging of the object. Computerized Tomography, Computerized Laminography, and Digital Radiography were important parts in Radiography. The institute of applied electronics, CAEP in the research of intense radiation had developed several advanced radiation sources and some advanced radiography imaging systems, for example, S-band small spot linear accelerator, full solid state modulator, C-band linear accelerator, high energy Tera-hertz radiation source and CT technology based on cone beam, DR technology, CL Technology etc. Such imaging systems had been applied in industrial NDT/NDE, security check, medical diagnosis, petroleum and gas pipeline inspection system etc.

  6. Liquid contrabands classification based on energy dispersive X-ray diffraction and hybrid discriminant analysis

    International Nuclear Information System (INIS)

    YangDai, Tianyi; Zhang, Li

    2016-01-01

    Energy dispersive X-ray diffraction (EDXRD) combined with hybrid discriminant analysis (HDA) has been utilized for classifying the liquid materials for the first time. The XRD spectra of 37 kinds of liquid contrabands and daily supplies were obtained using an EDXRD test bed facility. The unique spectra of different samples reveal XRD's capability to distinguish liquid contrabands from daily supplies. In order to create a system to detect liquid contrabands, the diffraction spectra were subjected to HDA which is the combination of principal components analysis (PCA) and linear discriminant analysis (LDA). Experiments based on the leave-one-out method demonstrate that HDA is a practical method with higher classification accuracy and lower noise sensitivity than the other methods in this application. The study shows the great capability and potential of the combination of XRD and HDA for liquid contrabands classification.

  7. Liquid contrabands classification based on energy dispersive X-ray diffraction and hybrid discriminant analysis

    Energy Technology Data Exchange (ETDEWEB)

    YangDai, Tianyi [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China); Zhang, Li, E-mail: zhangli@nuctech.com [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education (China)

    2016-02-01

    Energy dispersive X-ray diffraction (EDXRD) combined with hybrid discriminant analysis (HDA) has been utilized for classifying the liquid materials for the first time. The XRD spectra of 37 kinds of liquid contrabands and daily supplies were obtained using an EDXRD test bed facility. The unique spectra of different samples reveal XRD's capability to distinguish liquid contrabands from daily supplies. In order to create a system to detect liquid contrabands, the diffraction spectra were subjected to HDA which is the combination of principal components analysis (PCA) and linear discriminant analysis (LDA). Experiments based on the leave-one-out method demonstrate that HDA is a practical method with higher classification accuracy and lower noise sensitivity than the other methods in this application. The study shows the great capability and potential of the combination of XRD and HDA for liquid contrabands classification.

  8. Liquid contrabands classification based on energy dispersive X-ray diffraction and hybrid discriminant analysis

    Science.gov (United States)

    YangDai, Tianyi; Zhang, Li

    2016-02-01

    Energy dispersive X-ray diffraction (EDXRD) combined with hybrid discriminant analysis (HDA) has been utilized for classifying the liquid materials for the first time. The XRD spectra of 37 kinds of liquid contrabands and daily supplies were obtained using an EDXRD test bed facility. The unique spectra of different samples reveal XRD's capability to distinguish liquid contrabands from daily supplies. In order to create a system to detect liquid contrabands, the diffraction spectra were subjected to HDA which is the combination of principal components analysis (PCA) and linear discriminant analysis (LDA). Experiments based on the leave-one-out method demonstrate that HDA is a practical method with higher classification accuracy and lower noise sensitivity than the other methods in this application. The study shows the great capability and potential of the combination of XRD and HDA for liquid contrabands classification.

  9. Bayesian Maximum Entropy Based Algorithm for Digital X-ray Mammogram Processing

    Directory of Open Access Journals (Sweden)

    Radu Mutihac

    2009-06-01

    Full Text Available Basics of Bayesian statistics in inverse problems using the maximum entropy principle are summarized in connection with the restoration of positive, additive images from various types of data like X-ray digital mammograms. An efficient iterative algorithm for image restoration from large data sets based on the conjugate gradient method and Lagrange multipliers in nonlinear optimization of a specific potential function was developed. The point spread function of the imaging system was determined by numerical simulations of inhomogeneous breast-like tissue with microcalcification inclusions of various opacities. The processed digital and digitized mammograms resulted superior in comparison with their raw counterparts in terms of contrast, resolution, noise, and visibility of details.

  10. A CMOS active pixel sensor system for laboratory- based x-ray diffraction studies of biological tissue

    International Nuclear Information System (INIS)

    Bohndiek, Sarah E; Cook, Emily J; Arvanitis, Costas D; Olivo, Alessandro; Royle, Gary J; Clark, Andy T; Prydderch, Mark L; Turchetta, Renato; Speller, Robert D

    2008-01-01

    X-ray diffraction studies give material-specific information about biological tissue. Ideally, a large area, low noise, wide dynamic range digital x-ray detector is required for laboratory-based x-ray diffraction studies. The goal of this work is to introduce a novel imaging technology, the CMOS active pixel sensor (APS) that has the potential to fulfil all these requirements, and demonstrate its feasibility for coherent scatter imaging. A prototype CMOS APS has been included in an x-ray diffraction demonstration system. An industrial x-ray source with appropriate beam filtration is used to perform angle dispersive x-ray diffraction (ADXRD). Optimization of the experimental set-up is detailed including collimator options and detector operating parameters. Scatter signatures are measured for 11 different materials, covering three medical applications: breast cancer diagnosis, kidney stone identification and bone mineral density calculations. Scatter signatures are also recorded for three mixed samples of known composition. Results are verified using two independent models for predicting the APS scatter signature: (1) a linear systems model of the APS and (2) a linear superposition integral combining known monochromatic scatter signatures with the input polychromatic spectrum used in this case. Cross validation of experimental, modelled and literature results proves that APS are able to record biologically relevant scatter signatures. Coherent scatter signatures are sensitive to multiple materials present in a sample and provide a means to quantify composition. In the future, production of a bespoke APS imager for x-ray diffraction studies could enable simultaneous collection of the transmitted beam and scattered radiation in a laboratory-based coherent scatter system, making clinical transfer of the technique attainable

  11. State of the Art of X-ray Speckle-Based Phase-Contrast and Dark-Field Imaging

    Directory of Open Access Journals (Sweden)

    Marie-Christine Zdora

    2018-04-01

    Full Text Available In the past few years, X-ray phase-contrast and dark-field imaging have evolved to be invaluable tools for non-destructive sample visualisation, delivering information inaccessible by conventional absorption imaging. X-ray phase-sensing techniques are furthermore increasingly used for at-wavelength metrology and optics characterisation. One of the latest additions to the group of differential phase-contrast methods is the X-ray speckle-based technique. It has drawn significant attention due to its simple and flexible experimental arrangement, cost-effectiveness and multimodal character, amongst others. Since its first demonstration at highly brilliant synchrotron sources, the method has seen rapid development, including the translation to polychromatic laboratory sources and extension to higher-energy X-rays. Recently, different advanced acquisition schemes have been proposed to tackle some of the main limitations of previous implementations. Current applications of the speckle-based method range from optics characterisation and wavefront measurement to biomedical imaging and materials science. This review provides an overview of the state of the art of the X-ray speckle-based technique. Its basic principles and different experimental implementations as well as the the latest advances and applications are illustrated. In the end, an outlook for anticipated future developments of this promising technique is given.

  12. Nanoscale characterization of local structures and defects in photonic crystals using synchrotron-based transmission soft X-ray microscopy

    Science.gov (United States)

    Nho, Hyun Woo; Kalegowda, Yogesh; Shin, Hyun-Joon; Yoon, Tae Hyun

    2016-01-01

    For the structural characterization of the polystyrene (PS)-based photonic crystals (PCs), fast and direct imaging capabilities of full field transmission X-ray microscopy (TXM) were demonstrated at soft X-ray energy. PS-based PCs were prepared on an O2-plasma treated Si3N4 window and their local structures and defects were investigated using this label-free TXM technique with an image acquisition speed of ~10 sec/frame and marginal radiation damage. Micro-domains of face-centered cubic (FCC (111)) and hexagonal close-packed (HCP (0001)) structures were dominantly found in PS-based PCs, while point and line defects, FCC (100), and 12-fold symmetry structures were also identified as minor components. Additionally, in situ observation capability for hydrated samples and 3D tomographic reconstruction of TXM images were also demonstrated. This soft X-ray full field TXM technique with faster image acquisition speed, in situ observation, and 3D tomography capability can be complementally used with the other X-ray microscopic techniques (i.e., scanning transmission X-ray microscopy, STXM) as well as conventional characterization methods (e.g., electron microscopic and optical/fluorescence microscopic techniques) for clearer structure identification of self-assembled PCs and better understanding of the relationship between their structures and resultant optical properties. PMID:27087141

  13. Water equivalence of NIPAM based polymer gel dosimeters with enhanced sensitivity for x-ray CT

    International Nuclear Information System (INIS)

    Gorjiara, Tina; Hill, Robin; Bosi, Stephen; Kuncic, Zdenka; Baldock, Clive

    2013-01-01

    Two new formulations of N-isopropylacrylamide (NIPAM) based three dimensional (3D) gel dosimeters have recently been developed with improved sensitivity to x-ray CT readout, one without any co-solvent and the other one with isopropanol co-solvent. The water equivalence of the NIPAM gel dosimeters was investigated using different methods to calculate their radiological properties including: density, electron density, number of electrons per grams, effective atomic number, photon interaction probabilities, mass attenuation and energy absorption coefficients, electron collisional, radiative and total mass stopping powers and electron mass scattering power. Monte Carlo modelling was also used to compare the dose response of these gel dosimeters with water for kilovoltage and megavoltage x-ray beams and for megavoltage electron beams. We found that the density and electron density of the co-solvent free gel dosimeter are more water equivalent with less than a 2.6% difference compared to a 5.7% difference for the isopropanol gel dosimeter. Both the co-solvent free and isopropanol solvent gel dosimeters have lower effective atomic numbers than water, differing by 2.2% and 6.5%, respectively. As a result, their photoelectric absorption interaction probabilities are up to 6% and 19% different from water, respectively. Compton scattering and pair production interaction probabilities of NIPAM gel with isopropanol differ by up to 10% from water while for the co-solvent free gel, the differences are 3%. Mass attenuation and energy absorption coefficients of the co-solvent free gel dosimeter and the isopropanol gel dosimeter are up to 7% and 19% lower than water, respectively. Collisional and total mass stopping powers of both gel dosimeters differ by less than 2% from those of water. The dose response of the co-solvent free gel dosimeter is water equivalent (with 100 keV, correction factor is required for the gels. • For MV electron, correction factor needed for the gels to

  14. X-Ray Lasers 2016

    CERN Document Server

    Bulanov, Sergei; Daido, Hiroyuki; Kato, Yoshiaki

    2018-01-01

    These proceedings comprise a selection of invited and contributed papers presented at the 15th International Conference on X-Ray Lasers (ICXRL 2016), held at the Nara Kasugano International Forum, Japan, from May 22 to 27, 2016. This conference was part of an ongoing series dedicated to recent developments in the science and technology of x-ray lasers and other coherent x-ray sources with additional focus on supporting technologies, instrumentation and applications.   The book showcases recent advances in the generation of intense, coherent x-rays, the development of practical devices and their applications across a wide variety of fields. It also discusses emerging topics such as plasma-based x-ray lasers, 4th generation accelerator-based sources and higher harmonic generations, as well as other x-ray generation schemes.

  15. PINPIN a-Si:H based structures for X-ray image detection using the laser scanning technique

    Science.gov (United States)

    Fernandes, M.; Vygranenko, Y.; Vieira, M.

    2015-05-01

    Conventional film based X-ray imaging systems are being replaced by their digital equivalents. Different approaches are being followed by considering direct or indirect conversion, with the later technique dominating. The typical, indirect conversion, X-ray panel detector uses a phosphor for X-ray conversion coupled to a large area array of amorphous silicon based optical sensors and a couple of switching thin film transistors (TFT). The pixel information can then be readout by switching the correspondent line and column transistors, routing the signal to an external amplifier. In this work we follow an alternative approach, where the electrical switching performed by the TFT is replaced by optical scanning using a low power laser beam and a sensing/switching PINPIN structure, thus resulting in a simpler device. The optically active device is a PINPIN array, sharing both front and back electrical contacts, deposited over a glass substrate. During X-ray exposure, each sensing side photodiode collects photons generated by the scintillator screen (560 nm), charging its internal capacitance. Subsequently a laser beam (445 nm) scans the switching diodes (back side) retrieving the stored charge in a sequential way, reconstructing the image. In this paper we present recent work on the optoelectronic characterization of the PINPIN structure to be incorporated in the X-ray image sensor. The results from the optoelectronic characterization of the device and the dependence on scanning beam parameters are presented and discussed. Preliminary results of line scans are also presented.

  16. Some Applications of X-Ray Based Elemental Analysis Methods for Romanian Gold Minerals Studies

    International Nuclear Information System (INIS)

    Stan, D.; Constantinescu, B.; Pauna, C.; Neacsu, A.; Popescu, G.

    2009-01-01

    The elemental composition of gold, gold minerals and gold associated minerals releases important information's both from scientific (geologic) and economic point of view. In the present work, we focused on samples from Rosia Montana and Musariu ore deposits, from so called T ransylvanian gold of the golden q uadrilateral , Metaliferi Mountains. Our investigation started using optical microscopy. On the sample from Rosia Montana native gold band could be macroscopically seen. Gold occurs also like native gold in carbonate minerals, or associated with galena, sphalerite, chalcopyrite and quartz. The sample from Musariu shows native gold distributed at the border of sphalerite, native gold enclosed and along the margins of sphalerite and native gold between quartz grains. Three X-ray (the emission of characteristic lines spectra for each element present in the sample) based elemental analysis methods were also used: X-Ray Fluorescence (XRF), micro Synchrotron Radiation induced X-Ray Fluorescence (micro-SR-XRF) and micro Proton Induced X-Ray Emission (micro-PIXE). Our XRF methods are based on Xray tube spectrometers: a portable one - X-MET 3000TX and a stationary one - Spectro MIDEX. The two Rosia Montana and Musariu gold samples were studied using the micro-PIXE technique at the AN2000 accelerator of Laboratory Nazionale di Legnaro (LNL), INFN, Italy - maps and point spectra. The experiment was carried out with a 2 MeV proton microbeam (9 μm 2 beam area), maximum beam current 400 pA. The characteristic X-rays were measured with a Canberra HPGe detector (with 180 eV FWHM at 5.9 keV). Complementary experiments on the samples due the improved condition offered by the high energy X-rays, namely -Sb, Sn, Te detection, were performed at BESSY Synchrotron Radiation Facility, Berlin - point spectra. During the experiment, point spectra were acquired at 35 keV, excitation energy, using a spatially resolved synchrotron-radiation XRF setup detected to analyses. The XRF

  17. Fluctuations on the X-ray intensity beam using a portable X-ray probe based on {sup 6}LiI(Eu) crystal

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Geraldo P.; Oliveira, Arno H. [Universidade Federal de Minas Gerais (PCTN/UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares; Carneiro, Andre C.; Carneiro, Clemente J.G.; Milian, Felix M.; Velasco, Fermin G., E-mail: fermin@uesc.b [Universidade Estadual de Santa Cruz (CPqCTR/UESC), Ilheus, BA (Brazil). Centro de Pesquisa em Ciencias e Tecnologias das Radiacoes

    2011-07-01

    X-rays are produced by accelerating electrons with a high voltage and allowing them to collide with a metal target. This high voltage presents fluctuations that define peak, minimum, and average voltages. Different voltages are applied to the X-ray tube depending on the radiographic applications. A rectifier circuit converts the alternating high voltage to unidirectional high voltage to accelerate electrons in this tube. The fluctuations on the energy in the electron beam depend on the mode of rectification. Both energy of the electrons and X rays intensity fluctuates. A portable probe built with a {sup 6}LiI(Eu) detector coupled to a 10 m light guide and a Hamamatsu photon counting head H9319 was used to measuring X ray intensities. This system is designed to collect up to 10000 counts in intervals of 10 ms to 1 s. Counts were accumulated in time intervals of 10 ms during 10 s. The system starts the count before activating the X-ray apparatus, which is on during a time interval of 100ms. During this period, counts may overflow in consequence high voltage was adjusted to be 40kV, in order to avoid such a problem. For each of these points dose was measured using an ionization chamber. The objectives of this work are to study fluctuations on the X-ray beam and to calibrate the portable probe for measuring radiation doses. Counting rates measured for each 10 ms presented strong variations due to high voltages fluctuations. Both dose and counting rate when correlated with distances between source and detector followed the inverse square law and presented values of R2 near of unit. A calibration curve of the portable system for dose measurements showed also R2 value near of unity. (author)

  18. Note: Theoretical study on the gas pressure dependence of x-ray yield in TE111 cavity based electron cyclotron resonance x-ray source

    International Nuclear Information System (INIS)

    Selvakumaran, T. S.; Sen, Soubhadra; Baskaran, R.

    2014-01-01

    Adopting Langevin methodology, a pressure dependent frictional force term which represents the collisional effect is added to the Lorentz equation. The electrons are assumed to be starting from the uniformly distributed co-ordinates on the central plane. The trajectory of each electron is numerically simulated by solving the modified Lorentz equation for a given pressure. The Bremsstrahlung x-ray energy spectrum for each electron crossing the cavity wall boundary is obtained using the Duane-Hunt law. The total x-ray yield is estimated by adding the spectral contribution of each electron. The calculated yields are compared with the experimental results and a good agreement is found

  19. Simulations of x-ray speckle-based dark-field and phase-contrast imaging with a polychromatic beam

    Energy Technology Data Exchange (ETDEWEB)

    Zdora, Marie-Christine, E-mail: marie-christine.zdora@diamond.ac.uk [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Department of Physics & Astronomy, University College London, London WC1E 6BT (United Kingdom); Thibault, Pierre [Department of Physics & Astronomy, University College London, London WC1E 6BT (United Kingdom); Pfeiffer, Franz [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Zanette, Irene [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, 85748 Garching (Germany); Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom)

    2015-09-21

    Following the first experimental demonstration of x-ray speckle-based multimodal imaging using a polychromatic beam [I. Zanette et al., Phys. Rev. Lett. 112(25), 253903 (2014)], we present a simulation study on the effects of a polychromatic x-ray spectrum on the performance of this technique. We observe that the contrast of the near-field speckles is only mildly influenced by the bandwidth of the energy spectrum. Moreover, using a homogeneous object with simple geometry, we characterize the beam hardening artifacts in the reconstructed transmission and refraction angle images, and we describe how the beam hardening also affects the dark-field signal provided by speckle tracking. This study is particularly important for further implementations and developments of coherent speckle-based techniques at laboratory x-ray sources.

  20. Transport Measurements and Synchrotron-Based X-Ray Absorption Spectroscopy of Iron Silicon Germanide Grown by Molecular Beam Epitaxy

    Science.gov (United States)

    Elmarhoumi, Nader; Cottier, Ryan; Merchan, Greg; Roy, Amitava; Lohn, Chris; Geisler, Heike; Ventrice, Carl, Jr.; Golding, Terry

    2009-03-01

    Some of the iron-based metal silicide and germanide phases have been predicted to be direct band gap semiconductors. Therefore, they show promise for use as optoelectronic materials. We have used synchrotron-based x-ray absorption spectroscopy to study the structure of iron silicon germanide films grown by molecular beam epitaxy. A series of Fe(Si1-xGex)2 thin films (2000 -- 8000å) with a nominal Ge concentration of up to x = 0.04 have been grown. X-ray absorption near edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) measurements have been performed on the films. The nearest neighbor co-ordination corresponding to the β-FeSi2 phase of iron silicide provides the best fit with the EXAFS data. Temperature dependent (20 coefficient was calculated. Results suggest semiconducting behavior of the films which is consistent with the EXAFS results.

  1. Quantitative Analysis of Micro-Structure in Meat Emulsions from Grating-Based Multimodal X-Ray Tomography

    DEFF Research Database (Denmark)

    Einarsdottir, Hildur; Nielsen, Mikkel Schou; Miklos, Rikke

    2013-01-01

    Using novel X-ray techniques, based on grating-interferometry, new imaging modalities can be obtained simultaneously with absorption computed tomography (CT). These modalities, called phase contrast and dark field imaging, measure the electron density and the diffusion length of the sample....... Enhanced contrast capabilities of this X-ray technique makes studies on materials with similar attenuation properties possible. In this paper the focus is set on processing grating-based X-ray tomograms of meat emulsions to quantitatively measure micro-structural changes due to heat treatment. The emulsion...... samples were imaged both in a raw and cooked state. Additionally, different fat types were used in the emulsions in order to compare micro-structural differences when either pork fat or sunflower oil was used. From the reconstructed tomograms the different ingredients in the emulsions were segmented using...

  2. Impact of x-ray dose on track formation and data analysis for CR-39-based proton diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Rinderknecht, H. G., E-mail: rinderknecht1@llnl.gov; Rojas-Herrera, J.; Zylstra, A. B.; Frenje, J. A.; Gatu Johnson, M.; Sio, H.; Sinenian, N.; Rosenberg, M. J.; Li, C. K.; Séguin, F. H.; Petrasso, R. D. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Filkins, T.; Steidle, Jessica A.; Traynor, N.; Freeman, C. [State University of New York at Geneseo, Geneseo, New York 14454 (United States); Steidle, Jeffrey A. [Rochester Institute of Technology, Rochester, New York 14623 (United States)

    2015-12-15

    The nuclear track detector CR-39 is used extensively for charged particle diagnosis, in particular proton spectroscopy, at inertial confinement fusion facilities. These detectors can absorb x-ray doses from the experiments in the order of 1–100 Gy, the effects of which are not accounted for in the previous detector calibrations. X-ray dose absorbed in the CR-39 has previously been shown to affect the track size of alpha particles in the detector, primarily due to a measured reduction in the material bulk etch rate [Rojas-Herrera et al., Rev. Sci. Instrum. 86, 033501 (2015)]. Similar to the previous findings for alpha particles, protons with energies in the range 0.5–9.1 MeV are shown to produce tracks that are systematically smaller as a function of the absorbed x-ray dose in the CR-39. The reduction of track size due to x-ray dose is found to diminish with time between exposure and etching if the CR-39 is stored at ambient temperature, and complete recovery is observed after two weeks. The impact of this effect on the analysis of data from existing CR-39-based proton diagnostics on OMEGA and the National Ignition Facility is evaluated and best practices are proposed for cases in which the effect of x rays is significant.

  3. A Compact 5 MeV S-Band Electron Linac Based X-Ray Source for Industrial Radiography

    CERN Document Server

    Auditore, Lucrezia; De Pasquale, Domenico; Emanuele, Umberto; Italiano, Antonio; Trifirò, Antonio; Trimarchi, Marina

    2005-01-01

    A compact and reliable X-ray source, based on a 5 MeV, 1 kW, S-band electron linac, has been set up at the Dipartimento di Fisica, Universit\\'a di Messina. This source, coupled with a GOS scintillator screen and a CCD camera, represents an innovative transportable system for industrial radiography and X-ray tomography. Optimization of the parameters influencing the e-gamma conversion and the X-ray beam characteristics have been studied by means of the MCNP-4C2 code. The converter choice is the result of the study of the e-gamma conversion performances for different materials and materials thicknesses. Also the converter position with respect to the linac exit window was studied. The chosen converter consists in a Ta-Cu target inserted close to the linac window. The Cu layer acts as a filter both on the electrons from the source and on the low energy X-rays. The X-ray beam angular profile was studied by means of GafChromic films with and without collimation. In the final source project, a collimation system pr...

  4. Search for chameleons with an InGrid based X-ray detector at the CAST experiment

    Energy Technology Data Exchange (ETDEWEB)

    Desch, Klaus; Kaminski, Jochen; Krieger, Christoph; Schmidt, Sebastian [Physikalisches Institut, Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany)

    2016-07-01

    The CERN Axion Solar Telescope (CAST) searches for axions and also other exotic particles emerging from the Sun. Chameleons, for example, are part of Dark Energy theories. Like Axions they can be converted into soft X-ray photons in a high magnetic field and should result in an X-ray spectrum peaking below 1 keV. Because of their low energy and weak coupling, detectors with low energy threshold and low background rates are mandatory. Both requirements are met by an X-ray detector based on the combination of a Micromegas gas amplification stage with a highly integrated pixel chip which allows to make full use of the Micromegas structure's granularity. It has been demonstrated that these devices can detect even single electrons. Thus, allowing for a topological background suppression as well as for detection of low energy X-ray photons creating only very few primary electrons. After the detection threshold had been evaluated to be low enough to allow for the detection of the carbon K{sub α} line at 277 eV, the detector was mounted at one of CAST's X-ray telescopes and installed along with its infrastructure in 2014. During data taking until end of 2015 background rates of less than 10{sup -4} keV/(cm{sup 2}.s) have been achieved below 2 keV. First preliminary results of the ongoing chameleon analysis and possibly an improved limit for solar chameleons are presented.

  5. Applications of synchrotron-based X-ray fluorescence technique in materials science-possibilities at INDUS-2

    International Nuclear Information System (INIS)

    Tiwari, Manoj K.

    2016-01-01

    X-ray fluorescence (XRF) spectroscopy has seen remarkable progress over the last few decades. Numerous applications in basic and applied sciences demonstrate its importance. Various advantages of XRF technique have motivated us to construct a microfocus XRF beamline (BL-16) on Indus-2 national synchrotron radiation facility. The BL-16 beamline offers a wide range of usages - both from research laboratories and industries; and for researchers working in diverse fields. Apart from the fields of pure sciences like physics and chemistry, the beamline provides an attractive platform to exercise material science applications, interdisciplinary applied sciences like medical, forensic and environmental studies etc. In addition to micro-XRF characterization, BL-16 beamline allows a user to perform studies using other advanced synchrotron based experimental methodologies, viz; grazing incidence X-ray fluorescence (GIXRF) analysis, chemical speciation, near-edge absorption spectroscopy and X-ray reflectivity studies of thin layered materials etc. The combined XRR-GIXRF analysis feature of the BL-16 beamline offers a novel capability to perform GIXRF assisted depth resolved X-ray studies to investigate chemical state and electronic structure of the thin nano-structured materials. The design aspects and various salient features of the BL-16 beamline X-ray reflectometer will be presented along with the measured performance. (author)

  6. Impact of x-ray dose on track formation and data analysis for CR-39-based proton diagnostics

    International Nuclear Information System (INIS)

    Rinderknecht, H. G.; Rojas-Herrera, J.; Zylstra, A. B.; Frenje, J. A.; Gatu Johnson, M.; Sio, H.; Sinenian, N.; Rosenberg, M. J.; Li, C. K.; Séguin, F. H.; Petrasso, R. D.; Filkins, T.; Steidle, Jessica A.; Traynor, N.; Freeman, C.; Steidle, Jeffrey A.

    2015-01-01

    The nuclear track detector CR-39 is used extensively for charged particle diagnosis, in particular proton spectroscopy, at inertial confinement fusion facilities. These detectors can absorb x-ray doses from the experiments in the order of 1–100 Gy, the effects of which are not accounted for in the previous detector calibrations. X-ray dose absorbed in the CR-39 has previously been shown to affect the track size of alpha particles in the detector, primarily due to a measured reduction in the material bulk etch rate [Rojas-Herrera et al., Rev. Sci. Instrum. 86, 033501 (2015)]. Similar to the previous findings for alpha particles, protons with energies in the range 0.5–9.1 MeV are shown to produce tracks that are systematically smaller as a function of the absorbed x-ray dose in the CR-39. The reduction of track size due to x-ray dose is found to diminish with time between exposure and etching if the CR-39 is stored at ambient temperature, and complete recovery is observed after two weeks. The impact of this effect on the analysis of data from existing CR-39-based proton diagnostics on OMEGA and the National Ignition Facility is evaluated and best practices are proposed for cases in which the effect of x rays is significant

  7. Model-based image reconstruction in X-ray computed tomography

    NARCIS (Netherlands)

    Zbijewski, Wojciech Bartosz

    2006-01-01

    The thesis investigates the applications of iterative, statistical reconstruction (SR) algorithms in X-ray Computed Tomography. Emphasis is put on various aspects of system modeling in statistical reconstruction. Fundamental issues such as effects of object discretization and algorithm

  8. Adjustment and Prediction of X-Ray Machine Factors Based on Neural Artificial Inculcating

    International Nuclear Information System (INIS)

    Hussein, A.Z.; Amin, E.S.; Ibrahim, M.S.

    2009-01-01

    Since the discovery of X-rays, their use in examination has become an integral part of medical diagnostic radiology. The use of X-rays is harmful to human beings but recent technological advances and regulatory constraints have made the medical X-rays much safer than they were at the beginning of the 20th century. However, the potential benefits of the engineered safety features can not be fully realized unless the operators are aware of these safety features. The aim of this work is to adjust and predict X-ray machine factors (current and voltage) using neural artificial network in order to obtain effective dose within the range of dose limitation system and assure radiological safety.

  9. Laboratory source based full-field x-ray microscopy at 9 keV

    Energy Technology Data Exchange (ETDEWEB)

    Fella, C.; Balles, A.; Wiest, W. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Zabler, S.; Hanke, R. [Lehrstuhl für Röntgenmikroskopie, Julius-Maximilians-Universität, 97074 Würzburg (Germany); Fraunhofer Development Center X-Ray Technology (EZRT), Flugplatzstrasse 75, 90768 Fürth (Germany)

    2016-01-28

    In the past decade, hard x-ray transmission microscopy experienced tremendous developments. With the avail-ability of efficient Fresnel zone plates, even set-ups utilizing laboratory sources were developed [1]. In order to improve the performance of these x-ray microscopes, novel approaches to fabricate optical elements [2] and brighter x-ray tubes [3] are promising candidates. We are currently building a laboratory transmission x-ray microscope for 9.25 keV, using an electron impact liquid-metal-jet anode source. Up to now, the further elements of our setup are: a polycapillary condenser, a tungsten zone plate, and a scintillator which is optically coupled to a CMOS camera. However, further variations in terms of optical elements are intended. Here we present the current status of our work, as well as first experimental results.

  10. PINPIN a-Si:H based structures for X-ray image detection using the laser scanning technique

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, M., E-mail: mfernandes@isel.pt [Electronics Telecommunication and Computer Dept., ISEL, R.Conselheiro Emídio Navarro, 1959-007 Lisboa (Portugal); CTS-UNINOVA Quinta da Torre, Monte da Caparica, 2829-516 Caparica (Portugal); Vygranenko, Y.; Vieira, M. [Electronics Telecommunication and Computer Dept., ISEL, R.Conselheiro Emídio Navarro, 1959-007 Lisboa (Portugal); CTS-UNINOVA Quinta da Torre, Monte da Caparica, 2829-516 Caparica (Portugal)

    2015-05-01

    Highlights: • We present novel structure for X-ray image sensor based on the laser scanned technique. • Amorphous silicon based tandem structure characterization results are presented and discussed. • Results from preliminary tests of the imaging application are promising for very large area image sensing. - Abstract: Conventional film based X-ray imaging systems are being replaced by their digital equivalents. Different approaches are being followed by considering direct or indirect conversion, with the later technique dominating. The typical, indirect conversion, X-ray panel detector uses a phosphor for X-ray conversion coupled to a large area array of amorphous silicon based optical sensors and a couple of switching thin film transistors (TFT). The pixel information can then be readout by switching the correspondent line and column transistors, routing the signal to an external amplifier. In this work we follow an alternative approach, where the electrical switching performed by the TFT is replaced by optical scanning using a low power laser beam and a sensing/switching PINPIN structure, thus resulting in a simpler device. The optically active device is a PINPIN array, sharing both front and back electrical contacts, deposited over a glass substrate. During X-ray exposure, each sensing side photodiode collects photons generated by the scintillator screen (560 nm), charging its internal capacitance. Subsequently a laser beam (445 nm) scans the switching diodes (back side) retrieving the stored charge in a sequential way, reconstructing the image. In this paper we present recent work on the optoelectronic characterization of the PINPIN structure to be incorporated in the X-ray image sensor. The results from the optoelectronic characterization of the device and the dependence on scanning beam parameters are presented and discussed. Preliminary results of line scans are also presented.

  11. Two-dimensional x-ray magnification based on a monolithic beam conditioner

    Czech Academy of Sciences Publication Activity Database

    Korytár, D.; Mikulík, P.; Ferrari, C.; Hrdý, Jaromír; Baumbach, T.; Freund, A.; Kuběna, A.

    2003-01-01

    Roč. 36, - (2003), s. 1-4 ISSN 0022-3727 R&D Projects: GA AV ČR IAA1010104; GA MŠk OC P7.001 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray crystal diffraction * x-ray magnifier Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.265, year: 2003

  12. Information-theoretic discrepancy based iterative reconstructions (IDIR) for polychromatic x-ray tomography

    International Nuclear Information System (INIS)

    Jang, Kwang Eun; Lee, Jongha; Sung, Younghun; Lee, SeongDeok

    2013-01-01

    Purpose: X-ray photons generated from a typical x-ray source for clinical applications exhibit a broad range of wavelengths, and the interactions between individual particles and biological substances depend on particles' energy levels. Most existing reconstruction methods for transmission tomography, however, neglect this polychromatic nature of measurements and rely on the monochromatic approximation. In this study, we developed a new family of iterative methods that incorporates the exact polychromatic model into tomographic image recovery, which improves the accuracy and quality of reconstruction.Methods: The generalized information-theoretic discrepancy (GID) was employed as a new metric for quantifying the distance between the measured and synthetic data. By using special features of the GID, the objective function for polychromatic reconstruction which contains a double integral over the wavelength and the trajectory of incident x-rays was simplified to a paraboloidal form without using the monochromatic approximation. More specifically, the original GID was replaced with a surrogate function with two auxiliary, energy-dependent variables. Subsequently, the alternating minimization technique was applied to solve the double minimization problem. Based on the optimization transfer principle, the objective function was further simplified to the paraboloidal equation, which leads to a closed-form update formula. Numerical experiments on the beam-hardening correction and material-selective reconstruction were conducted to compare and assess the performance of conventional methods and the proposed algorithms.Results: The authors found that the GID determines the distance between its two arguments in a flexible manner. In this study, three groups of GIDs with distinct data representations were considered. The authors demonstrated that one type of GIDs that comprises “raw” data can be viewed as an extension of existing statistical reconstructions; under a

  13. Characterisation and application of a laser-based hard x-ray source

    International Nuclear Information System (INIS)

    Graetz, M.

    1998-11-01

    Hard X-rays are generated by focusing 110 fs laser pulses with intensities of about 1017 W/cm 2 onto solid metal targets. Characteristic properties of this X-ray source are the small source size, the short pulse duration and the high peak flux. The aim of the present work was to characterise this X-ray source and to demonstrate possible applications. A comparison with other X-ray sources and conventional imaging techniques is made. Characterising measurements were performed, including source size, emission spectrum, temporal behaviour, source stability and the influence of various laser parameters. The emission spectrum was measured using both energy-dispersive solid-state detectors and wavelength-dispersive crystal spectroscopy. The conversion efficiency from laser light to X-ray radiation was measured for different target materials. The laser ablation from different targets was studied. The feasibility of special imaging techniques, e.g. differential imaging and time-gated imaging, was investigated both theoretically and experimentally. Differential imaging allows for selective imaging of contrast agents, while time-gated imaging can reduce the influence of scattered radiation in X-ray imaging. Time-gated imaging was demonstrated in different imaging geometries, both for planar imaging and computed tomography imaging. Reasonable agreement between theoretically calculated values and experimental results was obtained

  14. Characterisation and application of a laser-based hard x-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Graetz, M

    1998-11-01

    Hard X-rays are generated by focusing 110 fs laser pulses with intensities of about 1017 W/cm{sup 2} onto solid metal targets. Characteristic properties of this X-ray source are the small source size, the short pulse duration and the high peak flux. The aim of the present work was to characterise this X-ray source and to demonstrate possible applications. A comparison with other X-ray sources and conventional imaging techniques is made. Characterising measurements were performed, including source size, emission spectrum, temporal behaviour, source stability and the influence of various laser parameters. The emission spectrum was measured using both energy-dispersive solid-state detectors and wavelength-dispersive crystal spectroscopy. The conversion efficiency from laser light to X-ray radiation was measured for different target materials. The laser ablation from different targets was studied. The feasibility of special imaging techniques, e.g. differential imaging and time-gated imaging, was investigated both theoretically and experimentally. Differential imaging allows for selective imaging of contrast agents, while time-gated imaging can reduce the influence of scattered radiation in X-ray imaging. Time-gated imaging was demonstrated in different imaging geometries, both for planar imaging and computed tomography imaging. Reasonable agreement between theoretically calculated values and experimental results was obtained 120 refs, figs, tabs

  15. Cybersecurity, massive data processing, community interaction, and other developments at WWW-based computational X-ray Server

    Science.gov (United States)

    Stepanov, Sergey

    2013-03-01

    X-Ray Server (x-server.gmca.aps.anl.gov) is a WWW-based computational server for modeling of X-ray diffraction, reflection and scattering data. The modeling software operates directly on the server and can be accessed remotely either from web browsers or from user software. In the later case the server can be deployed as a software library or a data fitting engine. As the server recently surpassed the milestones of 15 years online and 1.5 million calculations, it accumulated a number of technical solutions that are discussed in this paper. The developed approaches to detecting physical model limits and user calculations failures, solutions to spam and firewall problems, ways to involve the community in replenishing databases and methods to teach users automated access to the server programs may be helpful for X-ray researchers interested in using the server or sharing their own software online.

  16. Cybersecurity, massive data processing, community interaction, and other developments at WWW-based computational X-ray Server

    International Nuclear Information System (INIS)

    Stepanov, Sergey

    2013-01-01

    X-Ray Server (x-server.gmca.aps.anl.gov) is a WWW-based computational server for modeling of X-ray diffraction, reflection and scattering data. The modeling software operates directly on the server and can be accessed remotely either from web browsers or from user software. In the later case the server can be deployed as a software library or a data fitting engine. As the server recently surpassed the milestones of 15 years online and 1.5 million calculations, it accumulated a number of technical solutions that are discussed in this paper. The developed approaches to detecting physical model limits and user calculations failures, solutions to spam and firewall problems, ways to involve the community in replenishing databases and methods to teach users automated access to the server programs may be helpful for X-ray researchers interested in using the server or sharing their own software online.

  17. On-board event processing algorithms for a CCD-based space borne X-ray spectrometer

    International Nuclear Information System (INIS)

    Chun, H.J.; Bowles, J.A.; Branduardi-Raymont, G.; Gowen, R.A.

    1996-01-01

    This paper describes two alternative algorithms which are applied to reduce the telemetry requirements for a Charge Coupled Device (CCD) based, space-borne, X-ray spectrometer by on-board reconstruction of the X-ray events split over two or more adjacent pixels. The algorithms have been developed for the Reflection Grating Spectrometer (RGS) on the X-ray multi-mirror (XMM) mission, the second cornerstone project in the European Space Agency's Horizon 2000 programme. The overall instrument and some criteria which provide the background of the development of the algorithms, implemented in Tartan ADA on an MA31750 microprocessor, are described. The on-board processing constraints and requirements are discussed, and the performances of the algorithms are compared. Test results are presented which show that the recursive implementation is faster and has a smaller executable file although it uses more memory because of its stack requirements. (orig.)

  18. Measurement of X-ray mass attenuation coefficient of nickel around the K-edge using synchrotron radiation based X-ray absorption study

    International Nuclear Information System (INIS)

    Roy, Bunty Rani; Rajput, Parasmani; Jha, S.N.; Nageswara Rao, A.S.

    2015-01-01

    The work presents the X-ray absorption fine structure (XAFS) technique for measuring the X-ray mass attenuation coefficient of nickel metal foil in the X-ray energy range of 8271.2–8849.4 eV using scanning XAFS beam line (BL-09) at Indus-2 synchrotron radiation source facility, Raja Ramanna Centre for Advanced Technology (RRCAT) at Indore, India. The result represents the X-ray mass attenuation coefficient data for 0.02 mm thick Ni metal foil in the XAFS region of Ni K-edge. However, the results are compared to theoretical values using X-COM. There is a maximum deviation which is found exactly near the K-edge jump and decreases as we move away from the absorption edge. Oscillatory structure appears just above the observed absorption edge i.e., 8348.7 eV and is confined to around 250 eV above the edge. - Highlights: • Mass attenuation coefficient measurements of nickel using synchrotron radiation. • The measurements were taken exactly near the Ni K-edge at an energy step of 1 eV. • A maximum deviation is found near the K-edge

  19. Radiation dose reduction in medical x-ray CT via Fourier-based iterative reconstruction.

    Science.gov (United States)

    Fahimian, Benjamin P; Zhao, Yunzhe; Huang, Zhifeng; Fung, Russell; Mao, Yu; Zhu, Chun; Khatonabadi, Maryam; DeMarco, John J; Osher, Stanley J; McNitt-Gray, Michael F; Miao, Jianwei

    2013-03-01

    A Fourier-based iterative reconstruction technique, termed Equally Sloped Tomography (EST), is developed in conjunction with advanced mathematical regularization to investigate radiation dose reduction in x-ray CT. The method is experimentally implemented on fan-beam CT and evaluated as a function of imaging dose on a series of image quality phantoms and anonymous pediatric patient data sets. Numerical simulation experiments are also performed to explore the extension of EST to helical cone-beam geometry. EST is a Fourier based iterative algorithm, which iterates back and forth between real and Fourier space utilizing the algebraically exact pseudopolar fast Fourier transform (PPFFT). In each iteration, physical constraints and mathematical regularization are applied in real space, while the measured data are enforced in Fourier space. The algorithm is automatically terminated when a proposed termination criterion is met. Experimentally, fan-beam projections were acquired by the Siemens z-flying focal spot technology, and subsequently interleaved and rebinned to a pseudopolar grid. Image quality phantoms were scanned at systematically varied mAs settings, reconstructed by EST and conventional reconstruction methods such as filtered back projection (FBP), and quantified using metrics including resolution, signal-to-noise ratios (SNRs), and contrast-to-noise ratios (CNRs). Pediatric data sets were reconstructed at their original acquisition settings and additionally simulated to lower dose settings for comparison and evaluation of the potential for radiation dose reduction. Numerical experiments were conducted to quantify EST and other iterative methods in terms of image quality and computation time. The extension of EST to helical cone-beam CT was implemented by using the advanced single-slice rebinning (ASSR) method. Based on the phantom and pediatric patient fan-beam CT data, it is demonstrated that EST reconstructions with the lowest scanner flux setting of 39 m

  20. Radiation dose reduction in medical x-ray CT via Fourier-based iterative reconstruction

    International Nuclear Information System (INIS)

    Fahimian, Benjamin P.; Zhao Yunzhe; Huang Zhifeng; Fung, Russell; Zhu Chun; Miao Jianwei; Mao Yu; Khatonabadi, Maryam; DeMarco, John J.; McNitt-Gray, Michael F.; Osher, Stanley J.

    2013-01-01

    Purpose: A Fourier-based iterative reconstruction technique, termed Equally Sloped Tomography (EST), is developed in conjunction with advanced mathematical regularization to investigate radiation dose reduction in x-ray CT. The method is experimentally implemented on fan-beam CT and evaluated as a function of imaging dose on a series of image quality phantoms and anonymous pediatric patient data sets. Numerical simulation experiments are also performed to explore the extension of EST to helical cone-beam geometry. Methods: EST is a Fourier based iterative algorithm, which iterates back and forth between real and Fourier space utilizing the algebraically exact pseudopolar fast Fourier transform (PPFFT). In each iteration, physical constraints and mathematical regularization are applied in real space, while the measured data are enforced in Fourier space. The algorithm is automatically terminated when a proposed termination criterion is met. Experimentally, fan-beam projections were acquired by the Siemens z-flying focal spot technology, and subsequently interleaved and rebinned to a pseudopolar grid. Image quality phantoms were scanned at systematically varied mAs settings, reconstructed by EST and conventional reconstruction methods such as filtered back projection (FBP), and quantified using metrics including resolution, signal-to-noise ratios (SNRs), and contrast-to-noise ratios (CNRs). Pediatric data sets were reconstructed at their original acquisition settings and additionally simulated to lower dose settings for comparison and evaluation of the potential for radiation dose reduction. Numerical experiments were conducted to quantify EST and other iterative methods in terms of image quality and computation time. The extension of EST to helical cone-beam CT was implemented by using the advanced single-slice rebinning (ASSR) method. Results: Based on the phantom and pediatric patient fan-beam CT data, it is demonstrated that EST reconstructions with the lowest

  1. Film-based X-ray tomography combined with digital image processing: investigation of an ancient pattern-welded sword

    International Nuclear Information System (INIS)

    Lindegaard-Andersen, A.; Vedel, T.; Jeppesen, L.; Gottlieb, B.

    1988-01-01

    Film-based X-ray tomography and digital image processing have been used to investigate an inhomogeneous object of non-circular cross-section. The feasibility of using digital image processing to compensate for the poor contrast resolution inherent in film-based tomography has been demonstrated. (author)

  2. X-Ray

    Science.gov (United States)

    ... enema. What you can expect During the X-ray X-rays are performed at doctors' offices, dentists' offices, ... as those using a contrast medium. Your child's X-ray Restraints or other techniques may be used to ...

  3. Abdominal x-ray

    Science.gov (United States)

    Abdominal film; X-ray - abdomen; Flat plate; KUB x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

  4. Chest X-Ray

    Medline Plus

    Full Text Available ... talk with you about chest radiography also known as chest x-rays. Chest x-rays are the ... treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray ...

  5. Predictive sensor based x-ray calibration using a physical model

    International Nuclear Information System (INIS)

    Fuente, Matias de la; Lutz, Peter; Wirtz, Dieter C.; Radermacher, Klaus

    2007-01-01

    Many computer assisted surgery systems are based on intraoperative x-ray images. To achieve reliable and accurate results these images have to be calibrated concerning geometric distortions, which can be distinguished between constant distortions and distortions caused by magnetic fields. Instead of using an intraoperative calibration phantom that has to be visible within each image resulting in overlaying markers, the presented approach directly takes advantage of the physical background of the distortions. Based on a computed physical model of an image intensifier and a magnetic field sensor, an online compensation of distortions can be achieved without the need of an intraoperative calibration phantom. The model has to be adapted once to each specific image intensifier through calibration, which is based on an optimization algorithm systematically altering the physical model parameters, until a minimal error is reached. Once calibrated, the model is able to predict the distortions caused by the measured magnetic field vector and build an appropriate dewarping function. The time needed for model calibration is not yet optimized and takes up to 4 h on a 3 GHz CPU. In contrast, the time needed for distortion correction is less than 1 s and therefore absolutely acceptable for intraoperative use. First evaluations showed that by using the model based dewarping algorithm the distortions of an XRII with a 21 cm FOV could be significantly reduced. The model was able to predict and compensate distortions by approximately 80% to a remaining error of 0.45 mm (max) (0.19 mm rms)

  6. A fast pulse phase estimation method for X-ray pulsar signals based on epoch folding

    Directory of Open Access Journals (Sweden)

    Xue Mengfan

    2016-06-01

    Full Text Available X-ray pulsar-based navigation (XPNAV is an attractive method for autonomous deep-space navigation in the future. The pulse phase estimation is a key task in XPNAV and its accuracy directly determines the navigation accuracy. State-of-the-art pulse phase estimation techniques either suffer from poor estimation accuracy, or involve the maximization of generally non-convex object function, thus resulting in a large computational cost. In this paper, a fast pulse phase estimation method based on epoch folding is presented. The statistical properties of the observed profile obtained through epoch folding are developed. Based on this, we recognize the joint probability distribution of the observed profile as the likelihood function and utilize a fast Fourier transform-based procedure to estimate the pulse phase. Computational complexity of the proposed estimator is analyzed as well. Experimental results show that the proposed estimator significantly outperforms the currently used cross-correlation (CC and nonlinear least squares (NLS estimators, while significantly reduces the computational complexity compared with NLS and maximum likelihood (ML estimators.

  7. Breast tumor segmentation in high resolution x-ray phase contrast analyzer based computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Brun, E., E-mail: emmanuel.brun@esrf.fr [European Synchrotron Radiation Facility (ESRF), Grenoble 380000, France and Department of Physics, Ludwig-Maximilians University, Garching 85748 (Germany); Grandl, S.; Sztrókay-Gaul, A.; Gasilov, S. [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, 81377 Munich (Germany); Barbone, G. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States); Mittone, A.; Coan, P. [Department of Physics, Ludwig-Maximilians University, Garching 85748, Germany and Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, 81377 Munich (Germany); Bravin, A. [European Synchrotron Radiation Facility (ESRF), Grenoble 380000 (France)

    2014-11-01

    Purpose: Phase contrast computed tomography has emerged as an imaging method, which is able to outperform present day clinical mammography in breast tumor visualization while maintaining an equivalent average dose. To this day, no segmentation technique takes into account the specificity of the phase contrast signal. In this study, the authors propose a new mathematical framework for human-guided breast tumor segmentation. This method has been applied to high-resolution images of excised human organs, each of several gigabytes. Methods: The authors present a segmentation procedure based on the viscous watershed transform and demonstrate the efficacy of this method on analyzer based phase contrast images. The segmentation of tumors inside two full human breasts is then shown as an example of this procedure’s possible applications. Results: A correct and precise identification of the tumor boundaries was obtained and confirmed by manual contouring performed independently by four experienced radiologists. Conclusions: The authors demonstrate that applying the watershed viscous transform allows them to perform the segmentation of tumors in high-resolution x-ray analyzer based phase contrast breast computed tomography images. Combining the additional information provided by the segmentation procedure with the already high definition of morphological details and tissue boundaries offered by phase contrast imaging techniques, will represent a valuable multistep procedure to be used in future medical diagnostic applications.

  8. Breast tumor segmentation in high resolution x-ray phase contrast analyzer based computed tomography.

    Science.gov (United States)

    Brun, E; Grandl, S; Sztrókay-Gaul, A; Barbone, G; Mittone, A; Gasilov, S; Bravin, A; Coan, P

    2014-11-01

    Phase contrast computed tomography has emerged as an imaging method, which is able to outperform present day clinical mammography in breast tumor visualization while maintaining an equivalent average dose. To this day, no segmentation technique takes into account the specificity of the phase contrast signal. In this study, the authors propose a new mathematical framework for human-guided breast tumor segmentation. This method has been applied to high-resolution images of excised human organs, each of several gigabytes. The authors present a segmentation procedure based on the viscous watershed transform and demonstrate the efficacy of this method on analyzer based phase contrast images. The segmentation of tumors inside two full human breasts is then shown as an example of this procedure's possible applications. A correct and precise identification of the tumor boundaries was obtained and confirmed by manual contouring performed independently by four experienced radiologists. The authors demonstrate that applying the watershed viscous transform allows them to perform the segmentation of tumors in high-resolution x-ray analyzer based phase contrast breast computed tomography images. Combining the additional information provided by the segmentation procedure with the already high definition of morphological details and tissue boundaries offered by phase contrast imaging techniques, will represent a valuable multistep procedure to be used in future medical diagnostic applications.

  9. Dihydropyridines decrease X-ray-induced DNA base damage in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Wojewodzka, M., E-mail: marylaw@ichtj.waw.pl [Center of Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warszawa (Poland); Gradzka, I.; Buraczewska, I.; Brzoska, K.; Sochanowicz, B. [Center of Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warszawa (Poland); Goncharova, R.; Kuzhir, T. [Institute of Genetics and Cytology, Belarussian National Academy of Sciences, Minsk (Belarus); Szumiel, I. [Center of Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warszawa (Poland)

    2009-12-01

    Compounds with the structural motif of 1,4-dihydropyridine display a broad spectrum of biological activities, often defined as bioprotective. Among them are L-type calcium channel blockers, however, also derivatives which do not block calcium channels exert various effects at the cellular and organismal levels. We examined the effect of sodium 3,5-bis-ethoxycarbonyl-2,6-dimethyl-1,4-dihydropyridine-4-carboxylate (denoted here as DHP and previously also as AV-153) on X-ray-induced DNA damage and mutation frequency at the HGPRT (hypoxanthine-guanine phosphoribosyl transferase) locus in Chinese hamster ovary CHO-K1 cells. Using formamido-pyrimidine glycosylase (FPG) comet assay, we found that 1-h DHP (10 nM) treatment before X-irradiation considerably reduced the initial level of FPG-recognized DNA base damage, which was consistent with decreased 8-oxo-7,8-dihydro-2'-deoxyguanosine content and mutation frequency lowered by about 40%. No effect on single strand break rejoining or on cell survival was observed. Similar base damage-protective effect was observed for two calcium channel blockers: nifedipine (structurally similar to DHP) or verapamil (structurally unrelated). So far, the specificity of the DHP-caused reduction in DNA damage - practically limited to base damage - has no satisfactory explanation.

  10. Synthesis, X-ray Structure, Spectroscopic Properties and DFT Studies of a Novel Schiff Base

    Directory of Open Access Journals (Sweden)

    Kew-Yu Chen

    2014-10-01

    Full Text Available A series of Schiff bases, salicylideneaniline derivatives 1–4, was synthesized under mild conditions and characterized by 1H NMR, HRMS, UV-Vis and fluorescence spectra, and single-crystal X-ray diffraction. In solid and aprotic solvents 1–4 exist mainly as E conformers that possess an intramolecular six-membered-ring hydrogen bond. A weak intramolecular C–H×××F hydrogen bond is also observed in fluoro-functionalized Schiff base 4, which generates another S(6 ring motif. The C–H×××F hydrogen bond further stabilizes its structure and leads it to form a planar configuration. Compounds 1–3 exhibit solely a long-wavelength proton-transfer tautomer emission, while dipole-functionalized Schiff base 4 shows remarkable dual emission originated from the excited-state intramolecular charge transfer (ESICT and excited-state intramolecular proton transfer (ESIPT states. Furthermore, the geometric structures, frontier molecular orbitals (MOs and the potential energy curves for 1–4 in the ground and the first singlet excited state were fully rationalized by density functional theory (DFT and time-dependent DFT calculations.

  11. Lab-based ambient pressure X-ray photoelectron spectroscopy from past to present

    Science.gov (United States)

    Arble, Chris; Jia, Meng; Newberg, John T.

    2018-05-01

    Chemical interactions which occur at a heterogeneous interface between a gas and substrate are critical in many technological and natural processes. Ambient pressure X-ray photoelectron spectroscopy (AP-XPS) is a powerful spectroscopy tool that is inherently surface sensitive, elemental and chemical specific, with the ability to probe sample surfaces in the presence of a gas phase. In this review, we discuss the evolution of lab-based AP-XPS instruments, from the first development by Siegbahn and coworkers up through modern day systems. A comprehensive overview is given of heterogeneous experiments investigated to date via lab-based AP-XPS along with the different instrumental metrics that affect the quality of sample probing. We conclude with a discussion of future directions for lab-based AP-XPS, highlighting the efficacy for this in-demand instrument to continue to expand in its ability to significantly advance our understanding of surface chemical processes under in situ conditions in a technologically multidisciplinary setting.

  12. Tissue feature-based intra-fractional motion tracking for stereoscopic x-ray image guided radiotherapy

    Science.gov (United States)

    Xie, Yaoqin; Xing, Lei; Gu, Jia; Liu, Wu

    2013-06-01

    Real-time knowledge of tumor position during radiation therapy is essential to overcome the adverse effect of intra-fractional organ motion. The goal of this work is to develop a tumor tracking strategy by effectively utilizing the inherent image features of stereoscopic x-ray images acquired during dose delivery. In stereoscopic x-ray image guided radiation delivery, two orthogonal x-ray images are acquired either simultaneously or sequentially. The essence of markerless tumor tracking is the reliable identification of inherent points with distinct tissue features on each projection image and their association between two images. The identification of the feature points on a planar x-ray image is realized by searching for points with high intensity gradient. The feature points are associated by using the scale invariance features transform descriptor. The performance of the proposed technique is evaluated by using images of a motion phantom and four archived clinical cases acquired using either a CyberKnife equipped with a stereoscopic x-ray imaging system, or a LINAC equipped with an onboard kV imager and an electronic portal imaging device. In the phantom study, the results obtained using the proposed method agree with the measurements to within 2 mm in all three directions. In the clinical study, the mean error is 0.48 ± 0.46 mm for four patient data with 144 sequential images. In this work, a tissue feature-based tracking method for stereoscopic x-ray image guided radiation therapy is developed. The technique avoids the invasive procedure of fiducial implantation and may greatly facilitate the clinical workflow.

  13. Tissue feature-based intra-fractional motion tracking for stereoscopic x-ray image guided radiotherapy

    International Nuclear Information System (INIS)

    Xie Yaoqin; Gu Jia; Xing Lei; Liu Wu

    2013-01-01

    Real-time knowledge of tumor position during radiation therapy is essential to overcome the adverse effect of intra-fractional organ motion. The goal of this work is to develop a tumor tracking strategy by effectively utilizing the inherent image features of stereoscopic x-ray images acquired during dose delivery. In stereoscopic x-ray image guided radiation delivery, two orthogonal x-ray images are acquired either simultaneously or sequentially. The essence of markerless tumor tracking is the reliable identification of inherent points with distinct tissue features on each projection image and their association between two images. The identification of the feature points on a planar x-ray image is realized by searching for points with high intensity gradient. The feature points are associated by using the scale invariance features transform descriptor. The performance of the proposed technique is evaluated by using images of a motion phantom and four archived clinical cases acquired using either a CyberKnife equipped with a stereoscopic x-ray imaging system, or a LINAC equipped with an onboard kV imager and an electronic portal imaging device. In the phantom study, the results obtained using the proposed method agree with the measurements to within 2 mm in all three directions. In the clinical study, the mean error is 0.48 ± 0.46 mm for four patient data with 144 sequential images. In this work, a tissue feature-based tracking method for stereoscopic x-ray image guided radiation therapy is developed. The technique avoids the invasive procedure of fiducial implantation and may greatly facilitate the clinical workflow. (paper)

  14. Energy-angle correlation correction algorithm for monochromatic computed tomography based on Thomson scattering X-ray source

    Science.gov (United States)

    Chi, Zhijun; Du, Yingchao; Huang, Wenhui; Tang, Chuanxiang

    2017-12-01

    The necessity for compact and relatively low cost x-ray sources with monochromaticity, continuous tunability of x-ray energy, high spatial coherence, straightforward polarization control, and high brightness has led to the rapid development of Thomson scattering x-ray sources. To meet the requirement of in-situ monochromatic computed tomography (CT) for large-scale and/or high-attenuation materials based on this type of x-ray source, there is an increasing demand for effective algorithms to correct the energy-angle correlation. In this paper, we take advantage of the parametrization of the x-ray attenuation coefficient to resolve this problem. The linear attenuation coefficient of a material can be decomposed into a linear combination of the energy-dependent photoelectric and Compton cross-sections in the keV energy regime without K-edge discontinuities, and the line integrals of the decomposition coefficients of the above two parts can be determined by performing two spectrally different measurements. After that, the line integral of the linear attenuation coefficient of an imaging object at a certain interested energy can be derived through the above parametrization formula, and monochromatic CT can be reconstructed at this energy using traditional reconstruction methods, e.g., filtered back projection or algebraic reconstruction technique. Not only can monochromatic CT be realized, but also the distributions of the effective atomic number and electron density of the imaging object can be retrieved at the expense of dual-energy CT scan. Simulation results validate our proposal and will be shown in this paper. Our results will further expand the scope of application for Thomson scattering x-ray sources.

  15. X-ray astronomy

    International Nuclear Information System (INIS)

    Giacconi, R.; Gursky, H.

    1974-01-01

    This text contains ten chapters and three appendices. Following an introduction, chapters two through five deal with observational techniques, mechanisms for the production of x rays in a cosmic setting, the x-ray sky and solar x-ray emission. Chapters six through ten include compact x-ray sources, supernova remnants, the interstellar medium, extragalactic x-ray sources and the cosmic x-ray background. Interactions of x rays with matter, units and conversion factors and a catalog of x-ray sources comprise the three appendices. (U.S.)

  16. A measurement-based X-ray source model characterization for CT dosimetry computations.

    Science.gov (United States)

    Sommerville, Mitchell; Poirier, Yannick; Tambasco, Mauro

    2015-11-08

    The purpose of this study was to show that the nominal peak tube voltage potential (kVp) and measured half-value layer (HVL) can be used to generate energy spectra and fluence profiles for characterizing a computed tomography (CT) X-ray source, and to validate the source model and an in-house kV X-ray dose computation algorithm (kVDoseCalc) for computing machine- and patient-specific CT dose. Spatial variation of the X-ray source spectra of a Philips Brilliance and a GE Optima Big Bore CT scanner were found by measuring the HVL along the direction of the internal bow-tie filter axes. Third-party software, Spektr, and the nominal kVp settings were used to generate the energy spectra. Beam fluence was calculated by dividing the integral product of the spectra and the in-air NIST mass-energy attenuation coefficients by in-air dose measurements along the filter axis. The authors found the optimal number of photons to seed in kVDoseCalc to achieve dose convergence. The Philips Brilliance beams were modeled for 90, 120, and 140 kVp tube settings. The GE Optima beams were modeled for 80, 100, 120, and 140 kVp tube settings. Relative doses measured using a Capintec Farmer-type ionization chamber (0.65 cc) placed in a cylindrical polymethyl methacrylate (PMMA) phantom and irradiated by the Philips Brilliance, were compared to those computed with kVDoseCalc. Relative doses in an anthropomorphic thorax phantom (E2E SBRT Phantom) irradiated by the GE Optima were measured using a (0.015 cc) PTW Freiburg ionization chamber and compared to computations from kVDoseCalc. The number of photons required to reduce the average statistical uncertainty in dose to measurement over all 12 PMMA phantom positions was found to be 1.44%, 1.47%, and 1.41% for 90, 120, and 140 kVp, respectively. The maximum percent difference between calculation and measurement for all energies, measurement positions, and phantoms was less than 3.50%. Thirty-five out of a total of 36 simulation conditions were

  17. An x-ray-based capsule for colorectal cancer screening incorporating single photon counting technology

    Science.gov (United States)

    Lifshitz, Ronen; Kimchy, Yoav; Gelbard, Nir; Leibushor, Avi; Golan, Oleg; Elgali, Avner; Hassoon, Salah; Kaplan, Max; Smirnov, Michael; Shpigelman, Boaz; Bar-Ilan, Omer; Rubin, Daniel; Ovadia, Alex

    2017-03-01

    An ingestible capsule for colorectal cancer screening, based on ionizing-radiation imaging, has been developed and is in advanced stages of system stabilization and clinical evaluation. The imaging principle allows future patients using this technology to avoid bowel cleansing, and to continue the normal life routine during procedure. The Check-Cap capsule, or C-Scan ® Cap, imaging principle is essentially based on reconstructing scattered radiation, while both radiation source and radiation detectors reside within the capsule. The radiation source is a custom-made radioisotope encased in a small canister, collimated into rotating beams. While traveling along the human colon, irradiation occurs from within the capsule towards the colon wall. Scattering of radiation occurs both inside and outside the colon segment; some of this radiation is scattered back and detected by sensors onboard the capsule. During procedure, the patient receives small amounts of contrast agent as an addition to his/her normal diet. The presence of contrast agent inside the colon dictates the dominant physical processes to become Compton Scattering and X-Ray Fluorescence (XRF), which differ mainly by the energy of scattered photons. The detector readout electronics incorporates low-noise Single Photon Counting channels, allowing separation between the products of these different physical processes. Separating between radiation energies essentially allows estimation of the distance from the capsule to the colon wall, hence structural imaging of the intraluminal surface. This allows imaging of structural protrusions into the colon volume, especially focusing on adenomas that may develop into colorectal cancer.

  18. High sensitivity phase retrieval method in grating-based x-ray phase contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhao; Gao, Kun; Chen, Jian; Wang, Dajiang; Wang, Shenghao; Chen, Heng; Bao, Yuan; Shao, Qigang; Wang, Zhili, E-mail: wangnsrl@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China); Zhang, Kai [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Zhu, Peiping; Wu, Ziyu, E-mail: wuzy@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China and Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2015-02-15

    Purpose: Grating-based x-ray phase contrast imaging is considered as one of the most promising techniques for future medical imaging. Many different methods have been developed to retrieve phase signal, among which the phase stepping (PS) method is widely used. However, further practical implementations are hindered, due to its complex scanning mode and high radiation dose. In contrast, the reverse projection (RP) method is a novel fast and low dose extraction approach. In this contribution, the authors present a quantitative analysis of the noise properties of the refraction signals retrieved by the two methods and compare their sensitivities. Methods: Using the error propagation formula, the authors analyze theoretically the signal-to-noise ratios (SNRs) of the refraction images retrieved by the two methods. Then, the sensitivities of the two extraction methods are compared under an identical exposure dose. Numerical experiments are performed to validate the theoretical results and provide some quantitative insight. Results: The SNRs of the two methods are both dependent on the system parameters, but in different ways. Comparison between their sensitivities reveals that for the refraction signal, the RP method possesses a higher sensitivity, especially in the case of high visibility and/or at the edge of the object. Conclusions: Compared with the PS method, the RP method has a superior sensitivity and provides refraction images with a higher SNR. Therefore, one can obtain highly sensitive refraction images in grating-based phase contrast imaging. This is very important for future preclinical and clinical implementations.

  19. High sensitivity phase retrieval method in grating-based x-ray phase contrast imaging

    International Nuclear Information System (INIS)

    Wu, Zhao; Gao, Kun; Chen, Jian; Wang, Dajiang; Wang, Shenghao; Chen, Heng; Bao, Yuan; Shao, Qigang; Wang, Zhili; Zhang, Kai; Zhu, Peiping; Wu, Ziyu

    2015-01-01

    Purpose: Grating-based x-ray phase contrast imaging is considered as one of the most promising techniques for future medical imaging. Many different methods have been developed to retrieve phase signal, among which the phase stepping (PS) method is widely used. However, further practical implementations are hindered, due to its complex scanning mode and high radiation dose. In contrast, the reverse projection (RP) method is a novel fast and low dose extraction approach. In this contribution, the authors present a quantitative analysis of the noise properties of the refraction signals retrieved by the two methods and compare their sensitivities. Methods: Using the error propagation formula, the authors analyze theoretically the signal-to-noise ratios (SNRs) of the refraction images retrieved by the two methods. Then, the sensitivities of the two extraction methods are compared under an identical exposure dose. Numerical experiments are performed to validate the theoretical results and provide some quantitative insight. Results: The SNRs of the two methods are both dependent on the system parameters, but in different ways. Comparison between their sensitivities reveals that for the refraction signal, the RP method possesses a higher sensitivity, especially in the case of high visibility and/or at the edge of the object. Conclusions: Compared with the PS method, the RP method has a superior sensitivity and provides refraction images with a higher SNR. Therefore, one can obtain highly sensitive refraction images in grating-based phase contrast imaging. This is very important for future preclinical and clinical implementations

  20. Analytical X-ray line profile analysis based upon correlated dislocations

    International Nuclear Information System (INIS)

    Rao, S.; Houska, C.R.

    1988-01-01

    Recent advances describing X-ray line profiles analytically, in terms of a minimum number of parameters, are related to a theory based upon correlated dislocations. It is shown that a multiple convolution approach, based upon the Warren-Averbach (W-A) analysis, leads to a form that closely approximates the strain coefficient obtained by Krivoglaz, Martynenko and Ryaboshopka. This connection enables one to determine the dislocation density and the ratio of the correlation range parameter to the mean particle size. These two results are obtained most accurately from previous analytical approaches which make use of a statistical least-squares analysis. The W-A Fourier-series approach provides redundant information and does not focus on the critical parameters that relate to dislocation theory. Results so far are limited to b.c.c. materials. Results for cold-worked W, Mo, Nb, Cr and V are compared with highly imperfect sputtered films of Mo. A major difference is relatable to higher correlation of dislocations in cold-worked metals than is found in sputtered films deposited at low temperatures. However, in each case, the dislocation density is high. (orig.)

  1. Three Dimensional Digital Sieving of Asphalt Mixture Based on X-ray Computed Tomography

    Directory of Open Access Journals (Sweden)

    Chichun Hu

    2017-07-01

    Full Text Available In order to perform three-dimensional digital sieving based on X-ray computed tomography images, the definition of digital sieve size (DSS was proposed, which was defined as the minimum length of the minimum bounding squares of all possible orthographic projections of an aggregate. The corresponding program was developed to reconstruct aggregate structure and to obtain DSS. Laboratory experiments consisting of epoxy-filled aggregate specimens were conducted to investigate the difference between mechanical sieve analysis and the digital sieving technique. It was suggested that concave surface of aggregate was the possible reason for the disparity between DSS and mechanical sieve size. A comparison between DSS and equivalent diameter was also performed. Moreover, the digital sieving technique was adopted to evaluate the gradation of stone mastic asphalt mixtures. The results showed that the closest proximity of the laboratory gradation curve was achieved by calibrated DSS, among gradation curves based on calibrated DSS, un-calibrated DSS and equivalent diameter.

  2. An Inquiry-Based Project Focused on the X-Ray Powder Diffraction Analysis of Common Household Solids

    Science.gov (United States)

    Hulien, Molly L.; Lekse, Jonathan W.; Rosmus, Kimberly A.; Devlin, Kasey P.; Glenn, Jennifer R.; Wisneski, Stephen D.; Wildfong, Peter; Lake, Charles H.; MacNeil, Joseph H.; Aitken, Jennifer A.

    2015-01-01

    While X-ray powder diffraction (XRPD) is a fundamental analytical technique used by solid-state laboratories across a breadth of disciplines, it is still underrepresented in most undergraduate curricula. In this work, we incorporate XRPD analysis into an inquiry-based project that requires students to identify the crystalline component(s) of…

  3. Revisiting Bragg's X-ray microscope: Scatter based optical transient grating detection of pulsed ionising radiation

    International Nuclear Information System (INIS)

    Fullagar, Wilfred K.; Paganin, David M.; Hall, Chris J.

    2011-01-01

    Transient optical gratings for detecting ultrafast signals are routine for temporally resolved photochemical investigations. Many processes can contribute to the formation of such gratings; we indicate use of optically scattering centres that can be formed with highly variable latencies in different materials and devices using ionising radiation. Coherent light scattered by these centres can form the short-wavelength-to-optical-wavelength, incoherent-to-coherent basis of a Bragg X-ray microscope, with inherent scope for optical phasing. Depending on the dynamics of the medium chosen, the way is open to both ultrafast pulsed and integrating measurements. For experiments employing brief pulses, we discuss high-dynamic-range short-wavelength diffraction measurements with real-time optical reconstructions. Applications to optical real-time X-ray phase-retrieval are considered. -- Research highlights: → It is timely that the concept of Bragg's X-ray microscope be revisited. → Transient gratings can be used for X-ray all-optical information processing. → Applications to optical real-time X-ray phase-retrieval are considered.

  4. A user-friendly LabVIEW software platform for grating based X-ray phase-contrast imaging.

    Science.gov (United States)

    Wang, Shenghao; Han, Huajie; Gao, Kun; Wang, Zhili; Zhang, Can; Yang, Meng; Wu, Zhao; Wu, Ziyu

    2015-01-01

    X-ray phase-contrast imaging can provide greatly improved contrast over conventional absorption-based imaging for weakly absorbing samples, such as biological soft tissues and fibre composites. In this study, we introduced an easy and fast way to develop a user-friendly software platform dedicated to the new grating-based X-ray phase-contrast imaging setup at the National Synchrotron Radiation Laboratory of the University of Science and Technology of China. The control of 21 motorized stages, of a piezoelectric stage and of an X-ray tube are achieved with this software, it also covers image acquisition with a flat panel detector for automatic phase stepping scan. Moreover, a data post-processing module for signals retrieval and other custom features are in principle available. With a seamless integration of all the necessary functions in one software package, this platform greatly facilitate users' activities during experimental runs with this grating based X-ray phase contrast imaging setup.

  5. Soft X-ray synchrotron radiation spectroscopy study of molecule-based nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Lee, E. S.; Kim, D. H.; Kang, J. S.; Kim, P. [The Catholic University of Korea, Bucheon (Korea, Republic of); Kim, K. H. [Korea University, Jochiwon (Korea, Republic of); Baik, J. Y.; Shin, H. J. [POSTECH, Pohang (Korea, Republic of)

    2014-11-15

    The electronic structures of molecule-based nanoparticles, such as biomineralized Helicobacter pylori ferritin (Hpf), Heme, and RbCo[Fe(CN){sub 6}]H{sub 2}O (RbCoFe) Prussian blue analogue, have been investigated by employing photoemission spectroscopy and soft X-ray absorption spectroscopy. Fe ions are found to be nearly trivalent in Hpf and Heme nanoparticles, which provides evidence that the amount of magnetite (Fe{sub 3}O{sub 4}) should be negligible in the Hpf core and that the biomineralization of Fe oxides in the high-Fe-bound-state Hpf core arises from a hematite-like formation. On the other hand, Fe ions are nearly divalent and Co ions are Co{sup 2+}-Co{sup 3+} mixed-valent in RbCoFe. Therefore this finding suggests that the mechanism of the photo-induced transition in RbCoFe Prussian blue analogue is not a simple spin-state transition of Fe{sup 2+}-Co{sup 3+} → Fe{sup 3+}-Co{sup 2+}. It is likely that Co{sup 2+} ions have the high-spin configuration while Fe{sup 2+} ions have the low-spin configuration.

  6. A plastic miniature x-ray emission spectrometer based on the cylindrical von Hamos geometry

    International Nuclear Information System (INIS)

    Mattern, B. A.; Seidler, G. T.; Haave, M.; Pacold, J. I.; Gordon, R. A.; Planillo, J.; Quintana, J.; Rusthoven, B.

    2012-01-01

    We present a short working distance miniature x-ray emission spectrometer (miniXES) based on the cylindrical von Hamos geometry. We describe the general design principles for the spectrometer and detail a specific implementation that covers Kβ and valence level emission from Fe. Large spatial and angular access to the sample region provides compatibility with environmental chambers, microprobe, and pump/probe measurements. The primary spectrometer structure and optic is plastic, printed using a 3-dimensional rapid-prototype machine. The spectrometer is inexpensive to construct and is portable; it can be quickly set up at any focused beamline with a tunable narrow bandwidth monochromator. The sample clearance is over 27 mm, providing compatibility with a variety of environment chambers. An overview is also given of the calibration and data processing procedures, which are implemented by a multiplatform user-friendly software package. Finally, representative measurements are presented. Background levels are below the level of the Kβ 2,5 valence emission, the weakest diagram line in the system, and photometric analysis of count rates finds that the instrument is performing at the theoretical limit.

  7. Dynamic chest radiography: flat-panel detector (FPD) based functional X-ray imaging.

    Science.gov (United States)

    Tanaka, Rie

    2016-07-01

    Dynamic chest radiography is a flat-panel detector (FPD)-based functional X-ray imaging, which is performed as an additional examination in chest radiography. The large field of view (FOV) of FPDs permits real-time observation of the entire lungs and simultaneous right-and-left evaluation of diaphragm kinetics. Most importantly, dynamic chest radiography provides pulmonary ventilation and circulation findings as slight changes in pixel value even without the use of contrast media; the interpretation is challenging and crucial for a better understanding of pulmonary function. The basic concept was proposed in the 1980s; however, it was not realized until the 2010s because of technical limitations. Dynamic FPDs and advanced digital image processing played a key role for clinical application of dynamic chest radiography. Pulmonary ventilation and circulation can be quantified and visualized for the diagnosis of pulmonary diseases. Dynamic chest radiography can be deployed as a simple and rapid means of functional imaging in both routine and emergency medicine. Here, we focus on the evaluation of pulmonary ventilation and circulation. This review article describes the basic mechanism of imaging findings according to pulmonary/circulation physiology, followed by imaging procedures, analysis method, and diagnostic performance of dynamic chest radiography.

  8. Geometry of X-ray based measurement of residual strain at desired penetration depth

    Energy Technology Data Exchange (ETDEWEB)

    Morawiec, A. [Polish Academy of Sciences, Institute of Metallurgy and Materials Science, Krakow (Poland)

    2017-10-15

    X-ray based measurement of residual lattice strains at chosen penetration depth is one of the methods for investigating strain inhomogeneities in near-surface layers of polycrystalline materials. The measurement relies on determining shifts of Bragg peaks for various directions of the scattering vector with respect to the specimen. At each of these directions, to reach a given the penetration depth, a proper specimen orientation is required. The task of determining such orientations, albeit elementary, is quite intricate. The existing literature describes only partial solutions with unspecified domains of application, which fail if applied to beyond the domains. Therefore, geometric aspects of the measurement are analyzed in details. Explicit bounds on measurement parameters are given. The equation fundamental for the procedure is solved with respect to specimen orientations. For a given direction of the scattering vector, there are generally four different specimen orientations leading to the same penetration depth. This simple fact (overlooked in previous analyses) can be used for improving reliability of measurement results. Analytical formulas for goniometer angles representing these orientations are provided. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Powerful conveyer belt real-time online detection system based on x-ray

    Science.gov (United States)

    Rong, Feng; Miao, Chang-yun; Meng, Wei

    2009-07-01

    The powerful conveyer belt is widely used in the mine, dock, and so on. After used for a long time, internal steel rope of the conveyor belt may fracture, rust, joints moving, and so on .This would bring potential safety problems. A kind of detection system based on x-ray is designed in this paper. Linear array detector (LDA) is used. LDA cost is low, response fast; technology mature .Output charge of LDA is transformed into differential voltage signal by amplifier. This kind of signal have great ability of anti-noise, is suitable for long-distance transmission. The processor is FPGA. A IP core control 4-channel A/D convertor, achieve parallel output data collection. Soft-core processor MicroBlaze which process tcp/ip protocol is embedded in FPGA. Sampling data are transferred to a computer via Ethernet. In order to improve the image quality, algorithm of getting rid of noise from the measurement result and taking gain normalization for pixel value is studied and designed. Experiments show that this system work well, can real-time online detect conveyor belt of width of 2.0m and speed of 5 m/s, does not affect the production. Image is clear, visual and can easily judge the situation of conveyor belt.

  10. Application of skeletal age based on x-ray in selecting sports talents

    Science.gov (United States)

    Mao, Zongzhen; Xu, Guodong; Song, Tao

    2012-01-01

    Skeletal age has been studied and proved that for most elite athletes, it was coincident with the chronological ages when they were young. In order to explore the application of skeletal age in selecting sports talent, 32 athletes (female, chronological age 5-12 y) were chosen from the Gymnastics Training Base in this study. Their left hand-wrists were photographed with X-rays, and then the skeletal ages were estimated by Chinese version of the Tanner-Whitehouse Skeletal Maturity Assessment System. At the same time, their body shapes, functions, and sports ability were also measured. Results showed that 71.88% of the skeletal age was proportional to their chronological age (+/- 1 y); while 18.75% of the skeletal maturity was retarded by 1- 2 year, 9.37% of those was advanced more than 1 year. On the other hand, the body shape, functions and sports ability of the athletes were positively related with their skeletal maturity. This study proved that the determination of skeletal maturity is a reliable evaluation for selecting sports talent. A further study on the influence of gymnastics on the skeletal age is of great significance.

  11. Optimisation of a propagation-based x-ray phase-contrast micro-CT system

    Science.gov (United States)

    Nesterets, Yakov I.; Gureyev, Timur E.; Dimmock, Matthew R.

    2018-03-01

    Micro-CT scanners find applications in many areas ranging from biomedical research to material sciences. In order to provide spatial resolution on a micron scale, these scanners are usually equipped with micro-focus, low-power x-ray sources and hence require long scanning times to produce high resolution 3D images of the object with acceptable contrast-to-noise. Propagation-based phase-contrast tomography (PB-PCT) has the potential to significantly improve the contrast-to-noise ratio (CNR) or, alternatively, reduce the image acquisition time while preserving the CNR and the spatial resolution. We propose a general approach for the optimisation of the PB-PCT imaging system. When applied to an imaging system with fixed parameters of the source and detector this approach requires optimisation of only two independent geometrical parameters of the imaging system, i.e. the source-to-object distance R 1 and geometrical magnification M, in order to produce the best spatial resolution and CNR. If, in addition to R 1 and M, the system parameter space also includes the source size and the anode potential this approach allows one to find a unique configuration of the imaging system that produces the required spatial resolution and the best CNR.

  12. High-accuracy X-ray detector calibration based on cryogenic radiometry

    Science.gov (United States)

    Krumrey, M.; Cibik, L.; Müller, P.

    2010-06-01

    Cryogenic electrical substitution radiometers (ESRs) are absolute thermal detectors, based on the equivalence of electrical power and radiant power. Their core piece is a cavity absorber, which is typically made of copper to achieve a short response time. At higher photon energies, the use of copper prevents the operation of ESRs due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the electron storage ring BESSY II. The Monte Carlo simulation code Geant4 was applied to optimize its absorptance for photon energies of up to 60 keV. The measurement of the radiant power of monochromatized synchrotron radiation was achieved with relative standard uncertainties of less than 0.2 %, covering the entire photon energy range of three beamlines from 50 eV to 60 keV. Monochromatized synchrotron radiation of high spectral purity is used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative standard uncertainties below 0.3 %. For some silicon photodiodes, the photocurrent is not linear with the incident radiant power.

  13. High-accuracy X-ray detector calibration based on cryogenic radiometry

    International Nuclear Information System (INIS)

    Krumrey, M.; Cibik, L.; Mueller, P.

    2010-01-01

    Cryogenic electrical substitution radiometers (ESRs) are absolute thermal detectors, based on the equivalence of electrical power and radiant power. Their core piece is a cavity absorber, which is typically made of copper to achieve a short response time. At higher photon energies, the use of copper prevents the operation of ESRs due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the electron storage ring BESSY II. The Monte Carlo simulation code Geant4 was applied to optimize its absorptance for photon energies of up to 60 keV. The measurement of the radiant power of monochromatized synchrotron radiation was achieved with relative standard uncertainties of less than 0.2 %, covering the entire photon energy range of three beamlines from 50 eV to 60 keV. Monochromatized synchrotron radiation of high spectral purity is used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative standard uncertainties below 0.3 %. For some silicon photodiodes, the photocurrent is not linear with the incident radiant power.

  14. An X-ray scanner prototype based on a novel hybrid gaseous detector

    CERN Document Server

    Iacobaeus, C; Lund-Jensen, B; Peskov, Vladimir

    2007-01-01

    We have developed a prototype of a new type of hybrid X-ray detector. It contains a thin wall (few μm) edge- illuminated lead glass capillary plate (acting as a converter of X-rays photons to primary electrons) combined with a microgap parallel-plate avalanche chamber operating in various gas mixtures at 1 atm. The operation of these converters was studied in a wide range of X-ray energies (from 6 to 60 keV) at incident angles varying from 0° to 90°. The detection efficiency, depending on the geometry, photon's energy, incident angle and the mode of operation, was between a few and 40%. The position resolution achieved was 50 μm in digital form and was practically independent of the photon's energy or gas mixture. The developed detector may open new possibilities for medical imaging, for example in mammography, portal imaging, radiography (including security devices), crystallography and many other applications.

  15. An engineering development of fluoroscopic X-ray medical equipment based-on fluorescent screen

    International Nuclear Information System (INIS)

    Ferry Suyatno; I Putu Susila; Djoko Sukmono

    2011-01-01

    Fluoroscopic x-ray medical equipment uses fluorescent screen to capture structural image of organs. Unlike conventional x-ray equipment which uses film, in the fluoroscopic x-ray, the resulting image is visualized on the fluorescent screen and directly observed by physicians in the patients' rooms. In this study, we developed an image capture system that transforms the image on the fluorescent screen into digital data, which is then transferred to computer for visualization and further processing. By using this system, the observation of the resulting image can be done on a computer that is placed in the control room. The image can also be stored easily and at low cost compared to conventional film. The experiment shows that the system could be used to capture image of the object. However, its quality needs to be improved. In the future, the system will be modified and tested with different types of cameras to obtain better results. (author)

  16. CVD diamond based soft X-ray detector with fast response

    International Nuclear Information System (INIS)

    Li Fang; Hou Lifei; Su Chunxiao; Yang Guohong; Liu Shenye

    2010-01-01

    A soft X-ray detector has been made with high quality chemical vapor deposited (CVD) diamond and the electrical structure of micro-strip. Through the measurement of response time on a laser with the pulse width of 10 ps, the full width at half maximum of the data got in the oscilloscope was 115 ps. The rise time of the CVD diamond detector was calculated to be 49 ps. In the experiment on the laser prototype facility, the signal got by the CVD diamond detector was compared with that got by a soft X-ray spectrometer. Both signals coincided well. The detector is proved to be a kind of reliable soft X-ray detector with fast response and high signal-to-noise ratio. (authors)

  17. Photovoltaic x-ray detectors based on the GaAs epitaxial structures

    CERN Document Server

    Akhmadullin, R A; Dvoryankina, G G; Dikaev, Y M; Ermakov, M G; Ermakova, O N; Krikunov, A I; Kudryashov, A A; Petrov, A G; Telegin, A A

    2002-01-01

    The new photovoltaic detector of the X-ray radiation is proposed on the basis of the GaAs epitaxial structures, which operates with high efficiency of the charge carriers collection without shift voltage and at the room temperature. The structures are grown by the method of the gas-phase epitaxy on the n sup + -type highly-alloyed substrates. The range of sensitivity to the X-ray radiation is within the range of effective energies from 8 up to 120 keV. The detector maximum response in the current short circuit mode is determined

  18. Source of X-ray radiation based on back compton scattering

    CERN Document Server

    Bulyak, E V; Karnaukhov, I M; Kononenko, S G; Lapshin, V G; Mytsykov, A O; Telegin, Yu P; Shcherbakov, A A; Zelinsky, Andrey Yurij

    2000-01-01

    Applicability was studied and previous estimation was done of power X-ray beams generation by backward Compton scattering of a laser photon beam on a cooled down electron beam. The few MeV electron beam circulating in a compact storage ring can be cooled down by interaction of that beam with powerful laser radiation of micrometer wavelength to achieve normalized emittance of 10 sup - sup 7 m. A tunable X-ray source of photons of energy ranging from few keV up to a hundred keV could result from the interaction of the laser beam with a dense electron beam.

  19. Source of X-ray radiation based on back compton scattering

    Energy Technology Data Exchange (ETDEWEB)

    Bulyak, E.V.; Gladkikh, P.I.; Karnaukhov, I.M.; Kononenko, S.G.; Lapshin, V.I.; Mytsykov, A.O.; Telegin, Yu.N.; Shcherbakov, A.A. E-mail: shcherbakov@kipt.kharkov.ua; Zelinsky, A.Yu

    2000-06-21

    Applicability was studied and previous estimation was done of power X-ray beams generation by backward Compton scattering of a laser photon beam on a cooled down electron beam. The few MeV electron beam circulating in a compact storage ring can be cooled down by interaction of that beam with powerful laser radiation of micrometer wavelength to achieve normalized emittance of 10{sup -7} m. A tunable X-ray source of photons of energy ranging from few keV up to a hundred keV could result from the interaction of the laser beam with a dense electron beam.

  20. Source of X-ray radiation based on back compton scattering

    International Nuclear Information System (INIS)

    Bulyak, E.V.; Gladkikh, P.I.; Karnaukhov, I.M.; Kononenko, S.G.; Lapshin, V.I.; Mytsykov, A.O.; Telegin, Yu.N.; Shcherbakov, A.A.; Zelinsky, A.Yu.

    2000-01-01

    Applicability was studied and previous estimation was done of power X-ray beams generation by backward Compton scattering of a laser photon beam on a cooled down electron beam. The few MeV electron beam circulating in a compact storage ring can be cooled down by interaction of that beam with powerful laser radiation of micrometer wavelength to achieve normalized emittance of 10 -7 m. A tunable X-ray source of photons of energy ranging from few keV up to a hundred keV could result from the interaction of the laser beam with a dense electron beam

  1. Chest X-Ray

    Medline Plus

    Full Text Available ... about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed x-ray exams and use a very small dose of ... of the inside of the chest. A chest x-ray is used to evaluate the lungs, heart and ...

  2. A flexible and accurate quantification algorithm for electron probe X-ray microanalysis based on thin-film element yields

    Science.gov (United States)

    Schalm, O.; Janssens, K.

    2003-04-01

    Quantitative analysis by means of electron probe X-ray microanalysis (EPXMA) of low Z materials such as silicate glasses can be hampered by the fact that ice or other contaminants build up on the Si(Li) detector beryllium window or (in the case of a windowless detector) on the Si(Li) crystal itself. These layers act as an additional absorber in front of the detector crystal, decreasing the detection efficiency at low energies (philosophy often employed in quantitative analysis of X-ray fluorescence (XRF) and proton-induced X-ray emission (PIXE) data. This approach is based on the (experimental) determination of thin-film element yields, rather than starting from infinitely thick and single element calibration standards. These thin-film sensitivity coefficients can also be interpolated to allow quantification of elements for which no suitable standards are available. The change in detector efficiency can be monitored by collecting an X-ray spectrum of one multi-element glass standard. This information is used to adapt the previously determined thin-film sensitivity coefficients to the actual detector efficiency conditions valid on the day that the experiments were carried out. The main advantage of this method is that spectra collected from the standards and from the unknown samples should not be acquired within a short period of time. This new approach is evaluated for glass and metal matrices and is compared with a standard ZAF method.

  3. R and D toward a compact high-brilliance X-ray source based on channeling radiation

    Energy Technology Data Exchange (ETDEWEB)

    Piot, P.; Brau, C. A.; Gabella, W. E.; Choi, B. K.; Jarvis, J. D.; Lewellen, J. W.; Mendenhall, M. H.; Mihalcea, D. [Northern Illinois Center for Accelerator and Detector Development and Department of Physics, Northern Illinois University, DeKalb, IL 60115 (United States) and Accelerator Physics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Dept. of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN 37235 (United States) and Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University, Nashville, TN 37235 (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Physics Department and Combat Systems, Naval Postgraduate School, Monterey, CA 93943 (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Northern Illinois Center for Accelerator and Detector Development and Department of Physics, Northern Illinois University, DeKalb, IL 60115 (United States)

    2012-12-21

    X-rays have been valuable to a large number of fields including Science, Medicine, and Security. Yet, the availability of a compact high-spectral brilliance X-ray sources is limited. A technique to produce X-rays with spectral brilliance B{approx} 10{sup 12} photons.(mm-mrd){sup -2}. (0.1% BW){sup -1}.s{sup -1} is discussed. The method is based on the generation and acceleration of a low-emittance field-emitted electron bunches. The bunches are then focused on a diamond crystal thereby producing channeling radiation. In this paper, after presenting the overarching concept, we discuss the generation, acceleration and transport of the low-emittance bunches with parameters consistent with the production of high-brilliance X-rays through channeling radiation. We especially consider the example of the Advanced Superconducting Test Accelerator (ASTA) currently in construction at Fermilab where a proof-of-principle experiment is in preparation.

  4. The use of x-ray pulsar-based navigation method for interplanetary flight

    Science.gov (United States)

    Yang, Bo; Guo, Xingcan; Yang, Yong

    2009-07-01

    As interplanetary missions are increasingly complex, the existing unique mature interplanetary navigation method mainly based on radiometric tracking techniques of Deep Space Network can not meet the rising demands of autonomous real-time navigation. This paper studied the applications for interplanetary flights of a new navigation technology under rapid development-the X-ray pulsar-based navigation for spacecraft (XPNAV), and valued its performance with a computer simulation. The XPNAV is an excellent autonomous real-time navigation method, and can provide comprehensive navigation information, including position, velocity, attitude, attitude rate and time. In the paper the fundamental principles and time transformation of the XPNAV were analyzed, and then the Delta-correction XPNAV blending the vehicles' trajectory dynamics with the pulse time-of-arrival differences at nominal and estimated spacecraft locations within an Unscented Kalman Filter (UKF) was discussed with a background mission of Mars Pathfinder during the heliocentric transferring orbit. The XPNAV has an intractable problem of integer pulse phase cycle ambiguities similar to the GPS carrier phase navigation. This article innovatively proposed the non-ambiguity assumption approach based on an analysis of the search space array method to resolve pulse phase cycle ambiguities between the nominal position and estimated position of the spacecraft. The simulation results show that the search space array method are computationally intensive and require long processing time when the position errors are large, and the non-ambiguity assumption method can solve ambiguity problem quickly and reliably. It is deemed that autonomous real-time integrated navigation system of the XPNAV blending with DSN, celestial navigation, inertial navigation and so on will be the development direction of interplanetary flight navigation system in the future.

  5. X-ray sky

    International Nuclear Information System (INIS)

    Gruen, M.; Koubsky, P.

    1977-01-01

    The history is described of the discoveries of X-ray sources in the sky. The individual X-ray detectors are described in more detail, i.e., gas counters, scintillation detectors, semiconductor detectors, and the principles of X-ray spectrometry and of radiation collimation aimed at increased resolution are discussed. Currently, over 200 celestial X-ray sources are known. Some were identified as nebulae, in some pulsations were found or the source was identified as a binary star. X-ray bursts of novae were also observed. The X-ray radiation is briefly mentioned of spherical star clusters and of extragalactic X-ray sources. (Oy)

  6. In vivo x-ray phase contrast analyzer-based imaging for longitudinal osteoarthritis studies in guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Coan, Paola [Faculty of Medicine and Institute of Clinical Radiology, Ludwig-Maximilians University, Munich (Germany); Wagner, Andreas; Mollenhauer, Juergen [Department of Orthopaedics of the University of Jena, Rudolf-Elle-Hospital Eisenberg (Germany); Bravin, Alberto; Diemoz, Paul C; Keyrilaeinen, Jani, E-mail: Paola.Coan@physik.uni-muenchen.d [European Synchrotron Radiation Facility (ESRF), Grenoble (France)

    2010-12-21

    Over the last two decades phase contrast x-ray imaging techniques have been extensively studied for applications in the biomedical field. Published results demonstrate the high capability of these imaging modalities of improving the image contrast of biological samples with respect to standard absorption-based radiography and routinely used clinical imaging techniques. A clear depiction of the anatomic structures and a more accurate disease diagnosis may be provided by using radiation doses comparable to or lower than those used in current clinical methods. In the literature many works show images of phantoms and excised biological samples proving the high sensitivity of the phase contrast imaging methods for in vitro investigations. In this scenario, the applications of the so-called analyzer-based x-ray imaging (ABI) phase contrast technique are particularly noteworthy. The objective of this work is to demonstrate the feasibility of in vivo x-ray ABI phase contrast imaging for biomedical applications and in particular with respect to joint anatomic depiction and osteoarthritis detection. ABI in planar and tomographic modes was performed in vivo on articular joints of guinea pigs in order to investigate the animals with respect to osteoarthritis by using highly monochromatic x-rays of 52 keV and a low noise detector with a pixel size of 47 x 47 {mu}m{sup 2}. Images give strong evidence of the ability of ABI in depicting both anatomic structures in complex systems as living organisms and all known signs of osteoarthritis with high contrast, high spatial resolution and with an acceptable radiation dose. This paper presents the first proof of principle study of in vivo application of ABI. The technical challenges encountered when imaging an animal in vivo are discussed. This experimental study is an important step toward the study of clinical applications of phase contrast x-ray imaging techniques.

  7. Determination of chest x-ray cost using activity based costing approach at Penang General Hospital, Malaysia.

    Science.gov (United States)

    Atif, Muhammad; Sulaiman, Syed Azhar Syed; Shafie, Asrul Akmal; Saleem, Fahad; Ahmad, Nafees

    2012-01-01

    Activity based costing (ABC) is an approach to get insight of true costs and to solve accounting problems. It provides more accurate information on product cost than conventional accounting system. The purpose of this study was to identify detailed resource consumption for chest x-ray procedure. Human resource cost was calculated by multiplying the mean time spent by employees doing specific activity to their per-minute salaries. The costs of consumables and clinical equipments were obtained from the procurement section of the Radiology Department. The cost of the building was calculated by multiplying the area of space used by the chest X-ray facility with the unit cost of public building department. Moreover, straight-line deprecation with a discount rate of 3% was assumed for calculation of equivalent annual costs for building and machines. Cost of electricity was calculated by multiplying number of kilo watts used by electrical appliance in the year 2010 with electricity tariff for Malaysian commercial consumers (MYR 0.31 per kWh). Five activities were identified which were required to develop one chest X-ray film. Human resource, capital, consumable and electricity cost was MYR 1.48, MYR 1.98, MYR 2.15 and MYR 0.04, respectively. Total cost of single chest X-ray was MYR 5.65 (USD 1.75). By applying ABC approach, we can have more detailed and precise estimate of cost for specific activity or service. Choice of repeating a chest X-ray can be based on our findings, when cost is a limiting factor.

  8. A GEANT4 based simulation for pixelated X-ray hybrid detectors

    International Nuclear Information System (INIS)

    Marinho, F.; Akiba, K.

    2015-01-01

    In this letter we present a detailed Monte Carlo approach to simulate pixelated detectors for X-ray applications. It allows us to fully characterize quantities such as interaction probability and reconstructed energy deposits according to beam energy as to evaluate energy and position resolution for comparisons with experimental results. The implementation and use of Monte Carlo truth information is also discussed

  9. X-ray microbeams based on Kumakhov polycapillary optics and its ...

    Indian Academy of Sciences (India)

    because of the total external reflection of X-rays from the inner capillary walls .... of the area of apertures and walls, and losses on internal reflections. All these factors as a whole are considered in experimentally received transmission factor Tr.

  10. Moisture movement in cement-based repair systems monitored by X-ray absorption

    NARCIS (Netherlands)

    Lukovic, M.; Ye, G.; Schlangen, H.E.J.G.; van Breugel, K.

    2017-01-01

    In concrete repair systems, material properties in the repair material and interface are greatly influenced by the initial moisture content of the concrete (or mortar) substrate. In order to quantify moisture profiles inside the repair system, X-ray absorption was used. Preliminary studies are

  11. Visualization of magnetic dipolar interaction based on scanning transmission X-ray microscopy

    International Nuclear Information System (INIS)

    Ohtori, Hiroyuki; Iwano, Kaoru; Takeichi, Yasuo; Ono, Kanta; Mitsumata, Chiharu; Yano, Masao; Kato, Akira; Miyamoto, Noritaka; Shoji, Tetsuya; Manabe, Akira

    2014-01-01

    Using scanning transmission X-ray microscopy (STXM), in this report we visualized the magnetic dipolar interactions in nanocrystalline Nd-Fe-B magnets and imaged their magnetization distributions at various applied fields. We calculated the magnetic dipolar interaction by analyzing the interaction between the magnetization at each point and those at the other points on the STXM image.

  12. Upgrade of the InGrid based X-ray detector for the CAST experiment

    Energy Technology Data Exchange (ETDEWEB)

    Desch, Klaus; Kaminski, Jochen; Krieger, Christoph; Schmidt, Sebastian [Physikalisches Institut, Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany)

    2016-07-01

    The CERN Axion Solar Telescope (CAST) is a magnetic helioscope searching for solar axions and chameleons using the inverse Primakoff effect. The produced photons are in the low X-ray regime. Chameleon search demands high sensitivity to photons with less than 1 keV and a very low background rate. Several improvements to the detector design used in 2014/15 are envisaged for 2016. The readout system is to be improved by including a flash ADC to read out the analog signal induced on the grid. The pulse shape contains information about the longitudinal shape of the event in addition to the transverse shape given by the pixel read out. Tracks passing through the chip orthogonally resemble photons in transverse shape. A scintillator behind the detector will also allow cross referencing chip and and scintillator signals to further reduce background rates. Finally, a new X-ray window separating detector and X-ray telescope volume from one another will be installed. Due to the low expected signal rate, a window with very low X-ray opacity is needed. Due to a pressure difference of ∝1 bar between detector and the vacuum of CAST this is demanding. The usage of silicon nitride windows is being explored. The current progress of the detector upgrade will be presented.

  13. Study of X-ray source based on a small marx generator

    International Nuclear Information System (INIS)

    Jia Wei; Li Junna; Chen Weiqing; Tang Junping; He Xiaoping

    2014-01-01

    A 600 kV Marx generator accompanied with a water compression line, an output switch and a diode component is designed to generate the X ray with low energy level and low dose rate. The diode parameters are follows: gap space of anode and cathode is 3∼5 mm; cathode with ring structure is a graphite electrode which diameter is 40 mm; the anode is a tantalum target with a thickness of l.5 mm and a diameter of 200 mm. The study results show that: when the output voltage of Marx generator reaches to 550 kV, the voltage drop of the diode is 196 kV. And a low energy level, small dose rate X ray can be obtained in front of the anode. The X ray at the distance of 30 mm before the anode surface has a half width of 20 ns. The total energy dose of the X ray on the center of anode surface is 8 rad and dose rate is 4 × lO"8 rad/s, which have been measured by the method of thermoluminescence dosimetry. (authors)

  14. Microcontroller-based servo for two-crystal X-ray monochromators.

    Science.gov (United States)

    Siddons, D P

    1998-05-01

    Microcontrollers have become increasingly easy to incorporate into instruments as the architectures and support tools have developed. The PIC series is particularly easy to use, and this paper describes a controller used to stabilize the output of a two-crystal X-ray monochromator at a given offset from its peak intensity position, as such monochromators are generally used.

  15. Spectral information interpretation of X-ray analysis based on expert system approach

    International Nuclear Information System (INIS)

    Drakunov, Yu.M.; Lezin, A.N.; Pukha, N.P.; Silachev, I.Yu.

    2000-01-01

    An expert subprogram for automated identification for element composition of the samples of different nature according to the result of energy-dispersive X-ray fluorescence analysis is elaborated, The flowchart of the subprogram is presented, brief description of expert system structure and its algorithm is given. (author)

  16. Image-based metal artifact reduction in x-ray computed tomography utilizing local anatomical similarity

    Science.gov (United States)

    Dong, Xue; Yang, Xiaofeng; Rosenfield, Jonathan; Elder, Eric; Dhabaan, Anees

    2017-03-01

    X-ray computed tomography (CT) is widely used in radiation therapy treatment planning in recent years. However, metal implants such as dental fillings and hip prostheses can cause severe bright and dark streaking artifacts in reconstructed CT images. These artifacts decrease image contrast and degrade HU accuracy, leading to inaccuracies in target delineation and dose calculation. In this work, a metal artifact reduction method is proposed based on the intrinsic anatomical similarity between neighboring CT slices. Neighboring CT slices from the same patient exhibit similar anatomical features. Exploiting this anatomical similarity, a gamma map is calculated as a weighted summation of relative HU error and distance error for each pixel in an artifact-corrupted CT image relative to a neighboring, artifactfree image. The minimum value in the gamma map for each pixel is used to identify an appropriate pixel from the artifact-free CT slice to replace the corresponding artifact-corrupted pixel. With the proposed method, the mean CT HU error was reduced from 360 HU and 460 HU to 24 HU and 34 HU on head and pelvis CT images, respectively. Dose calculation accuracy also improved, as the dose difference was reduced from greater than 20% to less than 4%. Using 3%/3mm criteria, the gamma analysis failure rate was reduced from 23.25% to 0.02%. An image-based metal artifact reduction method is proposed that replaces corrupted image pixels with pixels from neighboring CT slices free of metal artifacts. This method is shown to be capable of suppressing streaking artifacts, thereby improving HU and dose calculation accuracy.

  17. Anatomy-based transmission factors for technique optimization in portable chest x-ray

    Science.gov (United States)

    Liptak, Christopher L.; Tovey, Deborah; Segars, William P.; Dong, Frank D.; Li, Xiang

    2015-03-01

    Portable x-ray examinations often account for a large percentage of all radiographic examinations. Currently, portable examinations do not employ automatic exposure control (AEC). To aid in the design of a size-specific technique chart, acrylic slabs of various thicknesses are often used to estimate x-ray transmission for patients of various body thicknesses. This approach, while simple, does not account for patient anatomy, tissue heterogeneity, and the attenuation properties of the human body. To better account for these factors, in this work, we determined x-ray transmission factors using computational patient models that are anatomically realistic. A Monte Carlo program was developed to model a portable x-ray system. Detailed modeling was done of the x-ray spectrum, detector positioning, collimation, and source-to-detector distance. Simulations were performed using 18 computational patient models from the extended cardiac-torso (XCAT) family (9 males, 9 females; age range: 2-58 years; weight range: 12-117 kg). The ratio of air kerma at the detector with and without a patient model was calculated as the transmission factor. Our study showed that the transmission factor decreased exponentially with increasing patient thickness. For the range of patient thicknesses examined (12-28 cm), the transmission factor ranged from approximately 21% to 1.9% when the air kerma used in the calculation represented an average over the entire imaging field of view. The transmission factor ranged from approximately 21% to 3.6% when the air kerma used in the calculation represented the average signals from two discrete AEC cells behind the lung fields. These exponential relationships may be used to optimize imaging techniques for patients of various body thicknesses to aid in the design of clinical technique charts.

  18. Model-based sphere localization (MBSL) in x-ray projections

    Science.gov (United States)

    Sawall, Stefan; Maier, Joscha; Leinweber, Carsten; Funck, Carsten; Kuntz, Jan; Kachelrieß, Marc

    2017-08-01

    The detection of spherical markers in x-ray projections is an important task in a variety of applications, e.g. geometric calibration and detector distortion correction. Therein, the projection of the sphere center on the detector is of particular interest as the used spherical beads are no ideal point-like objects. Only few methods have been proposed to estimate this respective position on the detector with sufficient accuracy and surrogate positions, e.g. the center of gravity, are used, impairing the results of subsequent algorithms. We propose to estimate the projection of the sphere center on the detector using a simulation-based method matching an artificial projection to the actual measurement. The proposed algorithm intrinsically corrects for all polychromatic effects included in the measurement and absent in the simulation by a polynomial which is estimated simultaneously. Furthermore, neither the acquisition geometry nor any object properties besides the fact that the object is of spherical shape need to be known to find the center of the bead. It is shown by simulations that the algorithm estimates the center projection with an error of less than 1% of the detector pixel size in case of realistic noise levels and that the method is robust to the sphere material, sphere size, and acquisition parameters. A comparison to three reference methods using simulations and measurements indicates that the proposed method is an order of magnitude more accurate compared to these algorithms. The proposed method is an accurate algorithm to estimate the center of spherical markers in CT projections in the presence of polychromatic effects and noise.

  19. Synchrotron-based transmission x-ray microscopy for improved extraction in shale during hydraulic fracturing

    Science.gov (United States)

    Kiss, Andrew M.; Jew, Adam D.; Joe-Wong, Claresta; Maher, Kate M.; Liu, Yijin; Brown, Gordon E.; Bargar, John

    2015-09-01

    Engineering topics which span a range of length and time scales present a unique challenge to researchers. Hydraulic fracturing (fracking) of oil shales is one of these challenges and provides an opportunity to use multiple research tools to thoroughly investigate a topic. Currently, the extraction efficiency from the shale is low but can be improved by carefully studying the processes at the micro- and nano-scale. Fracking fluid induces chemical changes in the shale which can have significant effects on the microstructure morphology, permeability, and chemical composition. These phenomena occur at different length and time scales which require different instrumentation to properly study. Using synchrotron-based techniques such as fluorescence tomography provide high sensitivity elemental mapping and an in situ micro-tomography system records morphological changes with time. In addition, the transmission X-ray microscope (TXM) at the Stanford Synchrotron Radiation Lightsource (SSRL) beamline 6-2 is utilized to collect a nano-scale three-dimensional representation of the sample morphology with elemental and chemical sensitivity. We present the study of a simplified model system, in which pyrite and quartz particles are mixed and exposed to oxidizing solution, to establish the basic understanding of the more complex geology-relevant oxidation reaction. The spatial distribution of the production of the oxidation reaction, ferrihydrite, is retrieved via full-field XANES tomography showing the reaction pathway. Further correlation between the high resolution TXM data and the high sensitivity micro-probe data provides insight into potential morphology changes which can decrease permeability and limit hydrocarbon recovery.

  20. Center for X-Ray Optics, 1986

    International Nuclear Information System (INIS)

    1987-07-01

    The Center for X-Ray Optics has made substantial progress during the past year on the development of very high resolution x-ray technologies, the generation of coherent radiation at x-ray wavelengths, and, based on these new developments, had embarked on several scientific investigations that would not otherwise have been possible. The investigations covered in this report are topics on x-ray sources, x-ray imaging and applications, soft x-ray spectroscopy, synchrotron radiation, advanced light source and magnet structures for undulators and wigglers

  1. X-ray diffraction

    International Nuclear Information System (INIS)

    Einstein, J.R.; Wei, C.H.

    1982-01-01

    We have been interested in structural elucidation by x-ray diffraction of compounds of biological interest. Understanding exactly how atoms are arranged in three-dimensional arrays as molecules can help explain the relationship between structure and functions. The species investigated may vary in size and shape; our recent studies included such diverse substances as antischistosomal drugs, a complex of cadmium with nucleic acid base, nitrate salts of adenine, and proteins

  2. Numerical design of in-line X-ray phase-contrast imaging based on ellipsoidal single-bounce monocapillary

    International Nuclear Information System (INIS)

    Sun, Weiyuan; Liu, Zhiguo; Sun, Tianxi; Peng, Song; Ma, Yongzhong; Ding, Xunliang

    2014-01-01

    A new device using an ellipsoidal single-bounce monocapillary X-ray optics was numerically designed to realize in-line X-ray phase-contrast imaging by using conventional laboratory X-ray source with a large spot. Numerical simulation results validated the effectiveness of the proposed device and approach. The ellipsoidal single-bounce monocapillary X-ray optics had potential applications in the in-line phase contrast imaging with polychromatic X-rays

  3. Numerical design of in-line X-ray phase-contrast imaging based on ellipsoidal single-bounce monocapillary

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Weiyuan; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stx@bnu.edu.cn [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Peng, Song [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2014-05-11

    A new device using an ellipsoidal single-bounce monocapillary X-ray optics was numerically designed to realize in-line X-ray phase-contrast imaging by using conventional laboratory X-ray source with a large spot. Numerical simulation results validated the effectiveness of the proposed device and approach. The ellipsoidal single-bounce monocapillary X-ray optics had potential applications in the in-line phase contrast imaging with polychromatic X-rays.

  4. Revisiting Bragg's X-ray microscope: scatter based optical transient grating detection of pulsed ionising radiation.

    Science.gov (United States)

    Fullagar, Wilfred K; Paganin, David M; Hall, Chris J

    2011-06-01

    Transient optical gratings for detecting ultrafast signals are routine for temporally resolved photochemical investigations. Many processes can contribute to the formation of such gratings; we indicate use of optically scattering centres that can be formed with highly variable latencies in different materials and devices using ionising radiation. Coherent light scattered by these centres can form the short-wavelength-to-optical-wavelength, incoherent-to-coherent basis of a Bragg X-ray microscope, with inherent scope for optical phasing. Depending on the dynamics of the medium chosen, the way is open to both ultrafast pulsed and integrating measurements. For experiments employing brief pulses, we discuss high-dynamic-range short-wavelength diffraction measurements with real-time optical reconstructions. Applications to optical real-time X-ray phase-retrieval are considered. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Electrostatic X-ray image recording device with mesh-base photocathode photoelectron discriminator means

    International Nuclear Information System (INIS)

    1977-01-01

    An electrostatic X-ray image recording device having a pair of spaced electrodes with a gas-filled gap therebetween, and including discrimination means, having a conductive mesh supporting a photocathodic material, positioned in the gas-filled gap between a first electrode having a layer of ultraviolet-emitting fluorescent material and a second electrode having a plastic sheet adjacent thereto for receiving photoelectrons emitted by the photocathodic material and accelerated to the second electrode by an applied field. The photoconductor-mesh element discriminates against fast electrons, produced by direct impingement of X-rays upon the photocathode to substantially reduce secondary electron production and amplification, thereby increasing both the signal-to-noise and contrast ratios. The electrostatic image formed on the plastic sheet is developed by zerographic techniques after exposure. (Auth.)

  6. Reverse engineering the ancient ceramic technology based on X-ray fluorescence spectromicroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sciau, Philippe; Leon, Yoanna; Goudeau, Philippe; Fakra, Sirine C.; Webb, Sam; Mehta, Apurva

    2011-07-06

    We present results of X-ray fluorescence (XRF) microprobe analyses of ancient ceramic cross-sections aiming at deciphering the different firing protocols used for their production. Micro-focused XRF elemental mapping, Fe chemical mapping and Fe K-edge X-ray absorption near edge structure spectroscopy were performed on pre-sigillata ceramics from southern Gaul, and terra Sigillata vessels from Italy and southern Gaul. Pieces from the different workshops and regions showed significant difference in the starting clay material, clay conditioning and kiln firing condition. By contrast, sherds from the same workshop exhibited more subtle differences and possible misfirings. Understanding the precise firing conditions and protocols would allow recreation of kilns for various productions. Furthermore, evolution and modification of kiln design would shed some light on how ancient potters devised solutions to diverse technological problems they encountered.

  7. Drug design based on x-ray diffraction and steered molecular dynamics

    Czech Academy of Sciences Publication Activity Database

    Hašek, Jindřich; Skálová, Tereza; Dohnálek, Jan; Dušková, Jarmila; Petroková, Hana; Vondráčková, Eva; Zimmermann, K.

    2005-01-01

    Roč. 12, č. 3 (2005), s. 208-210 ISSN 1211-5894. [VUFB Conference on Modern Methods in Synthesis and Analysis of Active Pharmaceutical Substances /5./. Praha, 23.11.2005-24.11.2005] R&D Projects: GA AV ČR KJB4050312 Institutional research plan: CEZ:AV0Z40500505 Keywords : drug design * X-ray diffraction * steered molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry

  8. Femtosecond and Subfemtosecond X-Ray Pulses from a SASE Based Free-Electron Laser

    Energy Technology Data Exchange (ETDEWEB)

    Emma, P

    2004-03-10

    We propose a novel method to generate femtosecond and sub-femtosecond photon pulses in a free electron laser by selectively spoiling the transverse emittance of the electron beam. Its merits are simplicity and ease of implementation. When the system is applied to the Linac Coherent Light Source, it can provide x-ray pulses the order of 1 femtosecond in duration containing about 1010 transversely coherent photons.

  9. Geometric calibration of a stationary digital breast tomosynthesis system based on distributed carbon nanotube X-ray source arrays.

    Directory of Open Access Journals (Sweden)

    Changhui Jiang

    Full Text Available Stationary digital breast tomosynthesis (sDBT with distributed X-ray sources based on carbon nanotube (CNT field emission cathodes has been recently proposed as an approach that can prevent motion blur produced by traditional DBT systems. In this paper, we simulate a geometric calibration method based on a proposed multi-source CNT X-ray sDBT system. This method is a projection matrix-based approach with seven geometric parameters, all of which can be obtained from only one projection datum of the phantom. To our knowledge, this study reports the first application of this approach in a CNT-based multi-beam X-ray sDBT system. The simulation results showed that the extracted geometric parameters from the calculated projection matrix are extremely close to the input values and that the proposed method is effective and reliable for a square sDBT system. In addition, a traditional cone-beam computed tomography (CT system was also simulated, and the uncalibrated and calibrated geometric parameters were used in image reconstruction based on the filtered back-projection (FBP method. The results indicated that the images reconstructed with calibrated geometric parameters have fewer artifacts and are closer to the reference image. All the simulation tests showed that this geometric calibration method is optimized for sDBT systems but can also be applied to other application-specific CT imaging systems.

  10. Geometric calibration of a stationary digital breast tomosynthesis system based on distributed carbon nanotube X-ray source arrays.

    Science.gov (United States)

    Jiang, Changhui; Zhang, Na; Gao, Juan; Hu, Zhanli

    2017-01-01

    Stationary digital breast tomosynthesis (sDBT) with distributed X-ray sources based on carbon nanotube (CNT) field emission cathodes has been recently proposed as an approach that can prevent motion blur produced by traditional DBT systems. In this paper, we simulate a geometric calibration method based on a proposed multi-source CNT X-ray sDBT system. This method is a projection matrix-based approach with seven geometric parameters, all of which can be obtained from only one projection datum of the phantom. To our knowledge, this study reports the first application of this approach in a CNT-based multi-beam X-ray sDBT system. The simulation results showed that the extracted geometric parameters from the calculated projection matrix are extremely close to the input values and that the proposed method is effective and reliable for a square sDBT system. In addition, a traditional cone-beam computed tomography (CT) system was also simulated, and the uncalibrated and calibrated geometric parameters were used in image reconstruction based on the filtered back-projection (FBP) method. The results indicated that the images reconstructed with calibrated geometric parameters have fewer artifacts and are closer to the reference image. All the simulation tests showed that this geometric calibration method is optimized for sDBT systems but can also be applied to other application-specific CT imaging systems.

  11. Estimating multi-phase pore-scale characteristics from X-ray tomographic data using cluster analysis-based segmentation

    DEFF Research Database (Denmark)

    Wildenschild, D.; Culligan, K.A.; Christensen, Britt Stenhøj Baun

    2006-01-01

    present in grey-scale X-ray tomographic images. The approach is based on a cluster analysis technique, used in combination with various other filtering and skeletonization schemes. We apply this segmentation algorithm to analyze multiphase pore-scale flow subjects such as hysteresis and interfacial...... characterization. The results clearly illustrate the advantage of using X-ray tomography together with cluster analysis-based image processing techniques. We were able to obtain detailed information on pore scale distribution of air and water phases, as well as quantitative measures of air bubble size and air...... of individual pores and interfaces. However, separation of the various phases (fluids and solids) in the grey-scale tomographic images has posed a major problem to quantitative analysis of the data. We present an image processing technique that facilitates identification and separation of the various phases...

  12. New medical imaging systems exploiting the energy dispersive X-ray diffraction with spectrometric CdZnTe based detector

    International Nuclear Information System (INIS)

    Barbes, Damien

    2016-01-01

    This thesis studies the interest of measuring the coherent scattering of X-rays for breast diagnosis imaging. Nowadays, most of X-ray-based medical imaging techniques use the information of X-rays attenuation through the tissues. It is the case for mammography, the most common breast imaging modality. The recent emergence of energy resolved detectors (based on semiconductors in particular) allows to consider using another phenomenon: the coherent X-ray scattering. Measurement of diffracted spectra can provide new information related to the molecular structure of the examined tissues, in order to improve their characterization and therefore improve the final diagnosis. Two modalities are considered: the breast cancer detection in vivo, following a suspicious mammography result, or biopsy analysis. The coherent scattering measurement system developed during this thesis work uses energy-resolved CdZnTe-based detectors, these detectors combining performances (energy resolution, sensitivity, spatial resolution, and compactness) promising for clinical application. This system is also based on the detector pixelation, which allows to provide an imaging modality capable of characterizing analyzed materials or tissues in one direction without any translation or rotation. A complete study of the measurement system is proposed in this thesis, structured in three main parts: modeling and simulation of the system, development of the processing of the data measured by the detector in order to image and characterize the analyzed sample and finally, designing of a new and more complex experimental setup based on a whole detector and multi-slit collimation system. An experimental validation is proposed for each of these three parts. (author) [fr

  13. Imaging properties of small-pixel spectroscopic x-ray detectors based on cadmium telluride sensors

    International Nuclear Information System (INIS)

    Koenig, Thomas; Schulze, Julia; Zuber, Marcus; Rink, Kristian; Oelfke, Uwe; Butzer, Jochen; Hamann, Elias; Cecilia, Angelica; Zwerger, Andreas; Fauler, Alex; Fiederle, Michael

    2012-01-01

    Spectroscopic x-ray imaging by means of photon counting detectors has received growing interest during the past years. Critical to the image quality of such devices is their pixel pitch and the sensor material employed. This paper describes the imaging properties of Medipix2 MXR multi-chip assemblies bump bonded to 1 mm thick CdTe sensors. Two systems were investigated with pixel pitches of 110 and 165 μm, which are in the order of the mean free path lengths of the characteristic x-rays produced in their sensors. Peak widths were found to be almost constant across the energy range of 10 to 60 keV, with values of 2.3 and 2.2 keV (FWHM) for the two pixel pitches. The average number of pixels responding to a single incoming photon are about 1.85 and 1.45 at 60 keV, amounting to detective quantum efficiencies of 0.77 and 0.84 at a spatial frequency of zero. Energy selective CT acquisitions are presented, and the two pixel pitches' abilities to discriminate between iodine and gadolinium contrast agents are examined. It is shown that the choice of the pixel pitch translates into a minimum contrast agent concentration for which material discrimination is still possible. We finally investigate saturation effects at high x-ray fluxes and conclude with the finding that higher maximum count rates come at the cost of a reduced energy resolution. (paper)

  14. A synchrotron-based X-ray exposure station for radiation biology experiments

    International Nuclear Information System (INIS)

    Thompson, A.C.; Blakely, E.A.; Bjornstad, K.A.; Chang, P.Y.; Rosen, C.J.; Schwarz, R.I.

    2007-01-01

    Synchrotron X-ray sources enable radiation biology experiments that are difficult with conventional sources. A synchrotron source can easily deliver a monochromatic, tunable energy, highly collimated X-ray beam of well-calibrated intensity. An exposure station at beamline 10.3.1 of the Advanced Light Source (ALS) has been developed which delivers a variable energy (5-20 keV) X-ray fan beam with very sharp edges (10-90% in less than 3 μm). A series of experiments have been done with a four-well slide where a stripe (100 μm widex18 mm long) of cells in each well has been irradiated and the dose varied from well to well. With this facility we have begun a series of experiments to study cells adjacent to irradiated cells and how they respond to the damage of their neighbors. Initial results have demonstrated the advantages of using synchrotron radiation for these experiments

  15. Report based on fiscal 2000 diagnostic X-ray equipment questionnaire survey. Conditions of radiography

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Mitsuo [Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Allied Health Sciences; Matsuura, Takatoshi [Sekishinkai Sayama Hospital, Saitama (Japan); Okuaki, Tomoyuki; Imai, Yoshio; Tsukamoto, Atsuko [Kanto Medical Center NTT EC, Tokyo (Japan); Ide, Toshinori [Kajima Corp., Tokyo (Japan). Kajima Clinic; Shinohara, Fuminori [Nippon Medical School, Kawasaki, Kanagawa (Japan). Second Hospital; Miyazaki, Shigeru [Toho Univ., Tokyo (Japan). Ohashi Hospital

    2002-08-01

    X-ray equipment has seen advances in inverters and the digitalization of reception systems. The X-ray Systems Study Group, in order to examine changes in the conditions of radiography, including pediatric radiography, variations in shortest irradiation time, and standardization of the conditions of radiography, carried out investigative research using a questionnaire survey that was sent to 400 facilities. The recovery rate was 33%. In terms of the reception system, half of the general radiography systems were using computed radiography (CR). Seventy percent of respondents used an intensifying screen and film (SEF) in stomach double-contrast radiography. About 80% used digital radiography (DR) and digital subtraction angiography (DSA) in aorta abdominalis angiography. At least 70% of high-voltage generators were of the inverter type. The conditions of radiography were not greatly influenced by changes in reception systems and X-ray equipment. Many pediatric radiographies were carried out by radiological technologists. We consider it useful to conduct such survey investigations. (author)

  16. [Report based on fiscal 2000 diagnostic x-ray equipment questionnaire survey(conditions of radiography)].

    Science.gov (United States)

    Ishikawa, Mitsuo; Matsuura, Takatoshi; Okuaki, Tomiyuki; Imai, Yoshio; Tsukamoto, Atsuko; Ide, Toshinori; Shinohara, Fuminori; Miyazaki, Shigeru

    2002-08-01

    X-ray equipment has seen advances in inverters and the digitalization of reception systems. The X-ray Systems Study Group, in order to examine changes in the conditions of radiography, including pediatric radiography, variations in shortest irradiation time, and standardization of the conditions of radiography, carried out investigative research using a questionnaire survey that was sent to 400 facilities. The recovery rate was 33%. In terms of the reception system, half of the general radiography systems were using computed radiography (CR). Seventy percent of respondents used an intensifying screen and film(S EF)in stomach double-contrast radiography. About 80% used digital radiography (DR) and digital subtraction angiography (DSA) in aorta abdominalis angiography. At least 70% of high-voltage generators were of the inverter type. The conditions of radiography were not greatly influenced by changes in reception systems and X-ray equipment. Many pediatric radiographies were carried out by radiological technologists. We consider it useful to conduct such survey investigations.

  17. A soft X-ray source based on a low divergence, high repetition rate ultraviolet laser

    Science.gov (United States)

    Crawford, E. A.; Hoffman, A. L.; Milroy, R. D.; Quimby, D. C.; Albrecht, G. F.

    The CORK code is utilized to evaluate the applicability of low divergence ultraviolet lasers for efficient production of soft X-rays. The use of the axial hydrodynamic code wih one ozone radial expansion to estimate radial motion and laser energy is examined. The calculation of ionization levels of the plasma and radiation rates by employing the atomic physics and radiation model included in the CORK code is described. Computations using the hydrodynamic code to determine the effect of laser intensity, spot size, and wavelength on plasma electron temperature are provided. The X-ray conversion efficiencies of the lasers are analyzed. It is observed that for a 1 GW laser power the X-ray conversion efficiency is a function of spot size, only weakly dependent on pulse length for time scales exceeding 100 psec, and better conversion efficiencies are obtained at shorter wavelengths. It is concluded that these small lasers focused to 30 micron spot sizes and 10 to the 14th W/sq cm intensities are useful sources of 1-2 keV radiation.

  18. A synchrotron-based X-ray exposure station for radiation biology experiments

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, A.C. [Division of Life Sciences, Lawrence Berkeley National Laboratory, Bld. 50A-6120, Berkeley, CA 94720 (United States)], E-mail: acthompson@lbl.gov; Blakely, E.A.; Bjornstad, K.A. [Division of Life Sciences, Lawrence Berkeley National Laboratory, Bld. 50A-6120, Berkeley, CA 94720 (United States); Chang, P.Y. [Division of Life Sciences, Lawrence Berkeley National Laboratory, Bld. 50A-6120, Berkeley, CA 94720 (United States); SRI International, Menlo Park, CA (United States); Rosen, C.J.; Schwarz, R.I. [Division of Life Sciences, Lawrence Berkeley National Laboratory, Bld. 50A-6120, Berkeley, CA 94720 (United States)

    2007-11-11

    Synchrotron X-ray sources enable radiation biology experiments that are difficult with conventional sources. A synchrotron source can easily deliver a monochromatic, tunable energy, highly collimated X-ray beam of well-calibrated intensity. An exposure station at beamline 10.3.1 of the Advanced Light Source (ALS) has been developed which delivers a variable energy (5-20 keV) X-ray fan beam with very sharp edges (10-90% in less than 3 {mu}m). A series of experiments have been done with a four-well slide where a stripe (100 {mu}m widex18 mm long) of cells in each well has been irradiated and the dose varied from well to well. With this facility we have begun a series of experiments to study cells adjacent to irradiated cells and how they respond to the damage of their neighbors. Initial results have demonstrated the advantages of using synchrotron radiation for these experiments.

  19. A compressed sensing based reconstruction algorithm for synchrotron source propagation-based X-ray phase contrast computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Melli, Seyed Ali, E-mail: sem649@mail.usask.ca [Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK (Canada); Wahid, Khan A. [Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK (Canada); Babyn, Paul [Department of Medical Imaging, University of Saskatchewan, Saskatoon, SK (Canada); Montgomery, James [College of Medicine, University of Saskatchewan, Saskatoon, SK (Canada); Snead, Elisabeth [Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK (Canada); El-Gayed, Ali [College of Medicine, University of Saskatchewan, Saskatoon, SK (Canada); Pettitt, Murray; Wolkowski, Bailey [College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK (Canada); Wesolowski, Michal [Department of Medical Imaging, University of Saskatchewan, Saskatoon, SK (Canada)

    2016-01-11

    Synchrotron source propagation-based X-ray phase contrast computed tomography is increasingly used in pre-clinical imaging. However, it typically requires a large number of projections, and subsequently a large radiation dose, to produce high quality images. To improve the applicability of this imaging technique, reconstruction algorithms that can reduce the radiation dose and acquisition time without degrading image quality are needed. The proposed research focused on using a novel combination of Douglas–Rachford splitting and randomized Kaczmarz algorithms to solve large-scale total variation based optimization in a compressed sensing framework to reconstruct 2D images from a reduced number of projections. Visual assessment and quantitative performance evaluations of a synthetic abdomen phantom and real reconstructed image of an ex-vivo slice of canine prostate tissue demonstrate that the proposed algorithm is competitive in reconstruction process compared with other well-known algorithms. An additional potential benefit of reducing the number of projections would be reduction of time for motion artifact to occur if the sample moves during image acquisition. Use of this reconstruction algorithm to reduce the required number of projections in synchrotron source propagation-based X-ray phase contrast computed tomography is an effective form of dose reduction that may pave the way for imaging of in-vivo samples.

  20. The effects of X-ray energy and an iodine-based contrast agent on chromosome aberrations

    International Nuclear Information System (INIS)

    Matsubara, Sho; Kubota, Nobuo; Katoh, Tsuguhisa; Yoshino, Norio; Sasaki, Takehito; Sasaki, Masao S.

    1994-01-01

    A study was undertaken to evaluate the effect of combining irradiation with X rays of various energies and an iodine-based contrast agent on the induction of chromosome aberrations in the peripheral lymphocytes of blood samples taken from healthy young donors. Although no enhancement of the effect of radiation was induced when blood samples with the iodine-based contrast agent were given 35 kV X irradiation, an 80 kV X-ray exposure induced an enhanced level of chromosome aberrations, and a 250 kV X irradiation, an enhancement of the frequencies of chromosome aberrations was seen in blood samples with the iodine-based contrast agent, especially when a Lucite phantom was employed in studies to increase the scattered rays. It was thus shown by microdosimetric analysis that X irradiation combined with an iodine-based contrast agent causes an enhancement of the absorbed radiation dose, which is dependent on the X-ray energies employed. This phenomenon may have clinical use in the radiotherapeutic management of tumors, although further extensive studies of tumor vascularity must be pursued before this can be applied clinically. 21 refs., 8 figs., 3 tabs

  1. Limited-angle tomography for analyzer-based phase-contrast x-ray imaging

    International Nuclear Information System (INIS)

    Majidi, Keivan; Wernick, Miles N; Brankov, Jovan G; Li, Jun; Muehleman, Carol

    2014-01-01

    Multiple-image radiography (MIR) is an analyzer-based phase-contrast x-ray imaging method, which is emerging as a potential alternative to conventional radiography. MIR simultaneously generates three planar parametric images containing information about scattering, refraction and attenuation properties of the object. The MIR planar images are linear tomographic projections of the corresponding object properties, which allows reconstruction of volumetric images using computed tomography (CT) methods. However, when acquiring a full range of linear projections around the tissue of interest is not feasible or the scanning time is limited, limited-angle tomography techniques can be used to reconstruct these volumetric images near the central plane, which is the plane that contains the pivot point of the tomographic movement. In this work, we use computer simulations to explore the applicability of limited-angle tomography to MIR. We also investigate the accuracy of reconstructions as a function of number of tomographic angles for a fixed total radiation exposure. We use this function to find an optimal range of angles over which data should be acquired for limited-angle tomography MIR (LAT-MIR). Next, we apply the LAT-MIR technique to experimentally acquired MIR projections obtained in a cadaveric human thumb study. We compare the reconstructed slices near the central plane to the same slices reconstructed by CT-MIR using the full angular view around the object. Finally, we perform a task-based evaluation of LAT-MIR performance for different numbers of angular views, and use template matching to detect cartilage in the refraction image near the central plane. We use the signal-to-noise ratio of this test as the detectability metric to investigate an optimum range of tomographic angles for detecting soft tissues in LAT-MIR. Both results show that there is an optimum range of angular view for data acquisition where LAT-MIR yields the best performance, comparable to CT

  2. Limited-angle tomography for analyzer-based phase-contrast x-ray imaging

    Science.gov (United States)

    Majidi, Keivan; Wernick, Miles N.; Li, Jun; Muehleman, Carol; Brankov, Jovan G.

    2014-07-01

    Multiple-image radiography (MIR) is an analyzer-based phase-contrast x-ray imaging method, which is emerging as a potential alternative to conventional radiography. MIR simultaneously generates three planar parametric images containing information about scattering, refraction and attenuation properties of the object. The MIR planar images are linear tomographic projections of the corresponding object properties, which allows reconstruction of volumetric images using computed tomography (CT) methods. However, when acquiring a full range of linear projections around the tissue of interest is not feasible or the scanning time is limited, limited-angle tomography techniques can be used to reconstruct these volumetric images near the central plane, which is the plane that contains the pivot point of the tomographic movement. In this work, we use computer simulations to explore the applicability of limited-angle tomography to MIR. We also investigate the accuracy of reconstructions as a function of number of tomographic angles for a fixed total radiation exposure. We use this function to find an optimal range of angles over which data should be acquired for limited-angle tomography MIR (LAT-MIR). Next, we apply the LAT-MIR technique to experimentally acquired MIR projections obtained in a cadaveric human thumb study. We compare the reconstructed slices near the central plane to the same slices reconstructed by CT-MIR using the full angular view around the object. Finally, we perform a task-based evaluation of LAT-MIR performance for different numbers of angular views, and use template matching to detect cartilage in the refraction image near the central plane. We use the signal-to-noise ratio of this test as the detectability metric to investigate an optimum range of tomographic angles for detecting soft tissues in LAT-MIR. Both results show that there is an optimum range of angular view for data acquisition where LAT-MIR yields the best performance, comparable to CT

  3. Characterization of structural properties of U and Pu in model systems by advanced synchrotron based X-ray spectroscopy

    International Nuclear Information System (INIS)

    Pidchenko, Ivan

    2016-01-01

    This dissertation presents the investigations of different U and Pu model systems relevant for safety assessment studies of nuclear waste repositories using the X-ray based synchrotron techniques: U and Pu L_3/M_4_,_5 edges HR-XANES, L_3 edge EXAFS and 3d4f RIXS as well as other complementary techniques, including XPS, XRD, SEM, TEM and UV-Vis-NIR techniques.

  4. Unit cell determination of epitaxial thin films based on reciprocal space vectors by high-resolution X-ray diffractometry

    OpenAIRE

    Yang, Ping; Liu, Huajun; Chen, Zuhuang; Chen, Lang; Wang, John

    2013-01-01

    A new approach, based on reciprocal space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry (HR-XRD). The lattice parameters of single crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of raw unit cell, subsequent conversion to the Niggli unit ...

  5. Alkali-developable silicone-based negative photoresist (SNP) for deep UV, electron beam, and X-ray lithographies

    International Nuclear Information System (INIS)

    Ban, Hiroshi; Tanaka, Akinobu; Kawai, Yoshio; Deguchi, Kimiyoshi

    1989-01-01

    A new silicone-based negative photoresist (SNP) developable with alkaline aqueous solutions is prepared. SNP composed of acetylated phenylsilsesquioxane oligomer and azidopyrene is applied to deep UV, electron beam (EB), and X-ray lithographies. SNP slightly swells in alkaline developers, thus exhibiting exceptionally high resolution characteristics for a negative resist. The resistance of SNP to oxygen reactive ion etching is approximately 30 times greater than that of conventional novolac resists. (author)

  6. X-ray crystallography, electrochemistry, spectral and thermal analysis of some tetradentate schiff base complexes and formation constant measurements

    Czech Academy of Sciences Publication Activity Database

    Asadi, Z.; Savarypour, N.; Dušek, Michal; Eigner, Václav

    2017-01-01

    Roč. 47, č. 11 (2017), s. 1501-1508 ISSN 2470-1556 R&D Projects: GA ČR(CZ) GA15-12653S Institutional support: RVO:68378271 Keywords : X-ray crystallography * transition metal Schiff base complexes * thermogravimetry * electrochemistry * formation constant measurements Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.)

  7. Radiomics-based differentiation of lung disease models generated by polluted air based on X-ray computed tomography data.

    Science.gov (United States)

    Szigeti, Krisztián; Szabó, Tibor; Korom, Csaba; Czibak, Ilona; Horváth, Ildikó; Veres, Dániel S; Gyöngyi, Zoltán; Karlinger, Kinga; Bergmann, Ralf; Pócsik, Márta; Budán, Ferenc; Máthé, Domokos

    2016-02-11

    Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann-Whitney post hoc (MWph) tests were used. Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas.

  8. Semiconductor X-ray detectors

    CERN Document Server

    Lowe, Barrie Glyn

    2014-01-01

    Identifying and measuring the elemental x-rays released when materials are examined with particles (electrons, protons, alpha particles, etc.) or photons (x-rays and gamma rays) is still considered to be the primary analytical technique for routine and non-destructive materials analysis. The Lithium Drifted Silicon (Si(Li)) X-Ray Detector, with its good resolution and peak to background, pioneered this type of analysis on electron microscopes, x-ray fluorescence instruments, and radioactive source- and accelerator-based excitation systems. Although rapid progress in Silicon Drift Detectors (SDDs), Charge Coupled Devices (CCDs), and Compound Semiconductor Detectors, including renewed interest in alternative materials such as CdZnTe and diamond, has made the Si(Li) X-Ray Detector nearly obsolete, the device serves as a useful benchmark and still is used in special instances where its large, sensitive depth is essential. Semiconductor X-Ray Detectors focuses on the history and development of Si(Li) X-Ray Detect...

  9. Self-regeneration mechanism of a perovskite-based catalyst studied with synchrotron radiation X-rays

    CERN Document Server

    Nishihata, Y

    2003-01-01

    A perovskite-based catalyst, LaFe sub 0 sub . sub 5 sub 7 Co sub 0 sub . sub 3 sub 8 Pd sub 0 sub . sub 0 sub 5 O sub 3 , maintains its high level of activity with high metal dispersion to control automotive emissions, such as nitrogen oxides (NO sub x), carbon monoxide (CO) and unburned hydrocarbons (HC). It has been demonstrated using X-ray anomalous diffraction (XAD) and X-ray absorption fine structure (XAFS) techniques that palladium reversibly moves between the inside and outside of the perovskite lattice, and that the agglomeration and growth of the metal particles is suppressed as a result of structural responses to the redox fluctuation in the exhaust-gas composition of current gasoline engines. (author)

  10. Noise analysis of grating-based x-ray differential phase-contrast imaging with angular signal radiography

    International Nuclear Information System (INIS)

    Faiz, Wali; Gao Kun; Wu Zhao; Wei Chen-Xi; Zan Gui-Bin; Tian Yang-Chao; Bao Yuan; Zhu Pei-Ping

    2017-01-01

    X-ray phase-contrast imaging is one of the novel techniques, and has potential to enhance image quality and provide the details of inner structures nondestructively. In this work, we investigate quantitatively signal-to-noise ratio (SNR) of grating-based x-ray phase contrast imaging (GBPCI) system by employing angular signal radiography (ASR). Moreover, photon statistics and mechanical error that is a major source of noise are investigated in detail. Results show the dependence of SNR on the system parameters and the effects on the extracted absorption, refraction and scattering images. Our conclusions can be used to optimize the system design for upcoming practical applications in the areas such as material science and biomedical imaging. (paper)

  11. A simulation-based study on the influence of beam hardening in X-ray computed tomography for dimensional metrology.

    Science.gov (United States)

    Lifton, Joseph J; Malcolm, Andrew A; McBride, John W

    2015-01-01

    X-ray computed tomography (CT) is a radiographic scanning technique for visualising cross-sectional images of an object non-destructively. From these cross-sectional images it is possible to evaluate internal dimensional features of a workpiece which may otherwise be inaccessible to tactile and optical instruments. Beam hardening is a physical process that degrades the quality of CT images and has previously been suggested to influence dimensional measurements. Using a validated simulation tool, the influence of spectrum pre-filtration and beam hardening correction are evaluated for internal and external dimensional measurements. Beam hardening is shown to influence internal and external dimensions in opposition, and to have a greater influence on outer dimensions compared to inner dimensions. The results suggest the combination of spectrum pre-filtration and a local gradient-based surface determination method are able to greatly reduce the influence of beam hardening in X-ray CT for dimensional metrology.

  12. Synchrotron X-ray scattering study on stratum corneum of skin. Toward applied research based upon basic research

    International Nuclear Information System (INIS)

    Hatta, Ichiro; Ohta, Noboru; Yagi, Naoto

    2008-01-01

    On considering the applied research on stratum corneum of skin, it is indispensable to know the structure at the molecular level. However, there is even now in a controversy among the researchers who are performing its X-ray scattering study. Here we introduce our solution for the two problems: One is the correlation between the lamellar structures and hydrocarbon-chain packings in intercellular lipid matrix and the other is the existence of water layers in the short lamellar structure. These studies have become possible for the first time by making good use of synchrotron small-angle/wide-angle X-ray diffraction. Based upon the structural evidence, we can further carry out the applied research in stratum corneum. (author)

  13. Gaseous electron multiplier-based soft x-ray plasma diagnostics development: Preliminary tests at ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Chernyshova, M., E-mail: maryna.chernyshova@ipplm.pl; Malinowski, K.; Czarski, T.; Kowalska-Strzęciwilk, E. [Institute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw (Poland); Wojeński, A.; Poźniak, K. T.; Kasprowicz, G.; Krawczyk, R.; Kolasiński, P.; Zabołotny, W.; Zienkiewicz, P. [Institute of Electronic Systems, Warsaw University of Technology, Nowowiejska 15/19, 00-665 Warsaw (Poland); Vezinet, D.; Herrmann, A. [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Mazon, D.; Jardin, A. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France)

    2016-11-15

    A Gaseous Electron Multiplier (GEM)-based detector is being developed for soft X-ray diagnostics on tokamaks. Its main goal is to facilitate transport studies of impurities like tungsten. Such studies are very relevant to ITER, where the excessive accumulation of impurities in the plasma core should be avoided. This contribution provides details of the preliminary tests at ASDEX Upgrade (AUG) with a focus on the most important aspects for detector operation in harsh radiation environment. It was shown that both spatially and spectrally resolved data could be collected, in a reasonable agreement with other AUG diagnostics. Contributions to the GEM signal include also hard X-rays, gammas, and neutrons. First simulations of the effect of high-energy photons have helped understanding these contributions.

  14. Development of quantitative x-ray microtomography

    International Nuclear Information System (INIS)

    Deckman, H.W.; Dunsmuir, J.A.; D'Amico, K.L.; Ferguson, S.R.; Flannery, B.P.

    1990-01-01

    The authors have developed several x-ray microtomography systems which function as quantitative three dimensional x-ray microscopes. In this paper the authors describe the evolutionary path followed from making the first high resolution experimental microscopes to later generations which can be routinely used for investigating materials. Developing the instrumentation for reliable quantitative x-ray microscopy using synchrotron and laboratory based x-ray sources has led to other imaging modalities for obtaining temporal and spatial two dimensional information

  15. Chest X-Ray

    Medline Plus

    Full Text Available ... some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to your health. While a chest x-ray use a ... posted: How to Obtain and Share ...

  16. Chest X-Ray

    Medline Plus

    Full Text Available ... X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey Rubin, a radiologist ... about chest x-rays, visit Radiology Info dot org. Thank you for your time! Spotlight Recently posted: ...

  17. X-ray apparatus

    International Nuclear Information System (INIS)

    Sell, L.J.

    1981-01-01

    A diagnostic x-ray device, readily convertible between conventional radiographic and tomographic operating modes, is described. An improved drive system interconnects and drives the x-ray source and the imaging device through coordinated movements for tomography

  18. X-ray - skeleton

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003381.htm X-ray - skeleton To use the sharing features on this ... Degenerative bone conditions Osteomyelitis Risks There is low radiation exposure. X-rays machines are set to provide the smallest ...

  19. X-ray electromagnetic application technology

    International Nuclear Information System (INIS)

    2011-01-01

    The investigating committee aimed at research on electromagnetic fields in functional devices and X-ray fibers for efficient coherent X-ray generation and their material science, high-precision manufacturing, particularly for X-ray electromagnetic application technology from January 2006 to December 2008. In this report, we describe our research results, in particular, on the topics of synchrotron radiation and free-electron laser, Saga Synchrotron Project, X-ray waveguides and waveguide-based lens-less hard-X-ray imaging, X-ray nanofocusing for capillaries and zone plates, dispersion characteristics in photonics crystal consisting of periodic atoms for nanometer waveguides, electromagnetic characteristics of grid structures for scattering fields of nano-meter electromagnetic waves and X-rays, FDTD parallel computing of fundamental scattering and attenuation characteristics of X-ray for medical imaging diagnosis, orthogonal relations of electromagnetic fields including evanescent field in dispersive medium. (author)

  20. A flexible and accurate quantification algorithm for electron probe X-ray microanalysis based on thin-film element yields

    International Nuclear Information System (INIS)

    Schalm, O.; Janssens, K.

    2003-01-01

    Quantitative analysis by means of electron probe X-ray microanalysis (EPXMA) of low Z materials such as silicate glasses can be hampered by the fact that ice or other contaminants build up on the Si(Li) detector beryllium window or (in the case of a windowless detector) on the Si(Li) crystal itself. These layers act as an additional absorber in front of the detector crystal, decreasing the detection efficiency at low energies (<5 keV). Since the layer thickness gradually changes with time, also the detector efficiency in the low energy region is not constant. Using the normal ZAF approach to quantification of EPXMA data is cumbersome in these conditions, because spectra from reference materials and from unknown samples must be acquired within a fairly short period of time in order to avoid the effect of the change in efficiency. To avoid this problem, an alternative approach to quantification of EPXMA data is proposed, following a philosophy often employed in quantitative analysis of X-ray fluorescence (XRF) and proton-induced X-ray emission (PIXE) data. This approach is based on the (experimental) determination of thin-film element yields, rather than starting from infinitely thick and single element calibration standards. These thin-film sensitivity coefficients can also be interpolated to allow quantification of elements for which no suitable standards are available. The change in detector efficiency can be monitored by collecting an X-ray spectrum of one multi-element glass standard. This information is used to adapt the previously determined thin-film sensitivity coefficients to the actual detector efficiency conditions valid on the day that the experiments were carried out. The main advantage of this method is that spectra collected from the standards and from the unknown samples should not be acquired within a short period of time. This new approach is evaluated for glass and metal matrices and is compared with a standard ZAF method

  1. Chest X-Ray

    Medline Plus

    Full Text Available ... I’d like to talk with you about chest radiography also known as chest x-rays. Chest x-rays are the most ... far outweighs any risk. For more information about chest x-rays, visit Radiology Info dot org. Thank you for your time! ...

  2. Chest X-Ray

    Medline Plus

    Full Text Available ... by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, ... you about chest radiography also known as chest x-rays. Chest x-rays are the most commonly performed ...

  3. 4D nano-tomography of electrochemical energy devices using lab-based X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Heenan, T. M. M.; Finegan, D. P.; Tjaden, B.; Lu, X.; Iacoviello, F.; Millichamp, J.; Brett, D. J. L.; Shearing, P. R.

    2018-05-01

    Electrochemical energy devices offer a variety of alternate means for low-carbon, multi-scale energy conversion and storage. Reactions in these devices are supported by electrodes with characteristically complex microstructures. To meet the increasing capacity and lifetime demands across a range of applications, it is essential to understand microstructural evolutions at a cell and electrode level which are thought to be critical aspects influencing material and device lifetime and performance. X-ray computed tomography (CT) has become a highly employed method for non-destructive characterisation of such microstructures with high spatial resolution. However, sub-micron resolutions present significant challenges for sample preparation and handling particularly in 4D studies, (three spatial dimensions plus time). Here, microstructural information is collected from the same region of interest within two electrode materials: a solid oxide fuel cell and the positive electrode from a lithium-ion battery. Using a lab-based X-ray instrument, tomograms with sub-micron resolutions were obtained between thermal cycling. The intricate microstructural evolutions captured within these two materials provide model examples of 4D X-ray nano-CT capabilities in tracking challenging degradation mechanisms. This technique is valuable in the advancement of electrochemical research as well as broader applications for materials characterisation.

  4. Lab-based x-ray tomography of a cochlear implant using energy discriminating detectors for metal artefact reduction

    Science.gov (United States)

    Yokhana, Viona S. K.; Arhatari, Benedicta D.; Gureyev, Timur E.; Abbey, Brian

    2018-01-01

    X-ray computed tomography (XCT) is an important clinical diagnostic tool which is also used in a range of biological imaging applications in research. The increasing prevalence of metallic implants in medical and dental radiography and tomography has driven the demand for new approaches to solving the issue of metal artefacts in XCT. Metal artefacts occur when a highly absorbing material is imaged which is in boundary contact with one or more weakly absorbing components, such as soft-tissue. The resulting `streaking' in the reconstructed images creates significant challenges for X-ray analysis due to the non-linear dependence on the absorption properties of the sample. In this paper we introduce a new approach to removing metal artefacts which exploits the capabilities of the recently available, photon-counting PiXirad detector. Our approach works for standard lab-based polychromatic X-ray tubes and does not rely on any postprocessing of the data. The method is demonstrated using both simulated data from a test phantom and experimental data collected from a cochlear implant. The results show that by combining the individual images, which are simultaneously generated for each different energy threshold, artefact -free segmentation of the implant from the surrounding biological tissue is achieved.

  5. A high-quality multilayer structure characterization method based on X-ray fluorescence and Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Brunetti, Antonio; Golosio, Bruno [Universita degli Studi di Sassari, Dipartimento di Scienze Politiche, Scienze della Comunicazione e Ingegneria dell' Informazione, Sassari (Italy); Melis, Maria Grazia [Universita degli Studi di Sassari, Dipartimento di Storia, Scienze dell' Uomo e della Formazione, Sassari (Italy); Mura, Stefania [Universita degli Studi di Sassari, Dipartimento di Agraria e Nucleo di Ricerca sulla Desertificazione, Sassari (Italy)

    2014-11-08

    X-ray fluorescence (XRF) is a well known nondestructive technique. It is also applied to multilayer characterization, due to its possibility of estimating both composition and thickness of the layers. Several kinds of cultural heritage samples can be considered as a complex multilayer, such as paintings or decorated objects or some types of metallic samples. Furthermore, they often have rough surfaces and this makes a precise determination of the structure and composition harder. The standard quantitative XRF approach does not take into account this aspect. In this paper, we propose a novel approach based on a combined use of X-ray measurements performed with a polychromatic beam and Monte Carlo simulations. All the information contained in an X-ray spectrum is used. This approach allows obtaining a very good estimation of the sample contents both in terms of chemical elements and material thickness, and in this sense, represents an improvement of the possibility of XRF measurements. Some examples will be examined and discussed. (orig.)

  6. Optimization of image quality and acquisition time for lab-based X-ray microtomography using an iterative reconstruction algorithm

    Science.gov (United States)

    Lin, Qingyang; Andrew, Matthew; Thompson, William; Blunt, Martin J.; Bijeljic, Branko

    2018-05-01

    Non-invasive laboratory-based X-ray microtomography has been widely applied in many industrial and research disciplines. However, the main barrier to the use of laboratory systems compared to a synchrotron beamline is its much longer image acquisition time (hours per scan compared to seconds to minutes at a synchrotron), which results in limited application for dynamic in situ processes. Therefore, the majority of existing laboratory X-ray microtomography is limited to static imaging; relatively fast imaging (tens of minutes per scan) can only be achieved by sacrificing imaging quality, e.g. reducing exposure time or number of projections. To alleviate this barrier, we introduce an optimized implementation of a well-known iterative reconstruction algorithm that allows users to reconstruct tomographic images with reasonable image quality, but requires lower X-ray signal counts and fewer projections than conventional methods. Quantitative analysis and comparison between the iterative and the conventional filtered back-projection reconstruction algorithm was performed using a sandstone rock sample with and without liquid phases in the pore space. Overall, by implementing the iterative reconstruction algorithm, the required image acquisition time for samples such as this, with sparse object structure, can be reduced by a factor of up to 4 without measurable loss of sharpness or signal to noise ratio.

  7. Testing of gadolinium oxy-sulphide phosphors for use in CCD-based X-ray detectors for macromolecular crystallography

    CERN Document Server

    Pokric, M

    2002-01-01

    The resolution and detective quantum efficiency of CCD-based detectors used for X-ray diffraction is primarily affected by the layer of phosphor that converts incident X-ray photons into visible photons. The optimum thickness of this phosphor layer is strongly dependent on the fraction of absorbed incident X-ray photons and required spatial resolution. A range of terbium doped gadolinium oxy-sulphide (Gd sub 2 O sub 2 S : Tb) phosphor samples, provided by Applied Scintillation Technologies, have been evaluated for spatial resolution, light output and uniformity. The phosphor samples varied in coating weight (10-25 mg/cm sup 2), grain size (2.5, 4, 10 mu m), and applied coating (no coating, reflectors and absorbers). In addition, a non-uniform layer was introduced to some samples in order to provide an inherent diffusion layer. The experimental results showed that the introduction of a reflector increases the point spread function (PSF) and increases light yield up to 30%, while an absorber reduces the PSF tai...

  8. A high-quality multilayer structure characterization method based on X-ray fluorescence and Monte Carlo simulation

    International Nuclear Information System (INIS)

    Brunetti, Antonio; Golosio, Bruno; Melis, Maria Grazia; Mura, Stefania

    2015-01-01

    X-ray fluorescence (XRF) is a well known nondestructive technique. It is also applied to multilayer characterization, due to its possibility of estimating both composition and thickness of the layers. Several kinds of cultural heritage samples can be considered as a complex multilayer, such as paintings or decorated objects or some types of metallic samples. Furthermore, they often have rough surfaces and this makes a precise determination of the structure and composition harder. The standard quantitative XRF approach does not take into account this aspect. In this paper, we propose a novel approach based on a combined use of X-ray measurements performed with a polychromatic beam and Monte Carlo simulations. All the information contained in an X-ray spectrum is used. This approach allows obtaining a very good estimation of the sample contents both in terms of chemical elements and material thickness, and in this sense, represents an improvement of the possibility of XRF measurements. Some examples will be examined and discussed. (orig.)

  9. Modernization of electron accelerator on the base of the RUP-400 x-ray unit

    International Nuclear Information System (INIS)

    Buslaev, I.I.; Kon'kov, N.G.; Kochetov, O.N.; Krylov, S.Yu.; Nikolaev, S.M.

    1976-01-01

    A device has been designed enabling one to change directly from the control panel relation of high to low energy electrons in the beam with a view to up-date a linear electron accelerator. The device comprises a high-voltage transformer accommodating an accelerating tube of the vacuum system with a titanium pump and a scanner. 1.5 BPV-2-400 X-ray tube with a renewable cathode is used as an accelerating tube. As a result of these modifications the accelerator has become smaller and not so heavy. Its characteristics on material irradiation have also improved

  10. X-ray radiation source based on a plasma filled diode

    Energy Technology Data Exchange (ETDEWEB)

    Popkov, N F; Kargin, V I; Ryaslov, E A; Pikar, A S [All-Russian Research Inst. of Experimental Physics, Sarov (Russian Federation). Russian Federal Nuclear Center

    1997-12-31

    The results are given of studies on a plasma X-ray source providing 2.5 krad of radiation dose per pulse over an area of 100 cm{sup 2} in the quantum energy range between 20 and 500 keV. The pulse duration was 100 ns. The spectral radiation distribution was obtained under various operating conditions of plasma and diode. A Marx generator served as the starting power source of 120 kJ with a discharge time of T/4=10{sup -6} s. A short electromagnetic pulse (10{sup -7} s) was shaped using plasma erosion opening switches. (author). 5 figs., 4 refs.

  11. Plasma-based X-ray laser at 21 nm for multidisciplinary applications

    Czech Academy of Sciences Publication Activity Database

    Mocek, Tomáš; Rus, Bedřich; Kozlová, Michaela; Polan, Jiří; Homer, Pavel; Jakubczak, Krzysztof; Stupka, Michal; Snopek, David; Nejdl, Jaroslav; Edwards, M.H.; Whittaker, D.S.; Tallents, G. J.; Mistry, P.; Pert, G. J.; Booth, N.; Zhai, Z.; Fajardo, M.; Zeitoun, P.; Chalupský, Jaromír; Hájková, Věra; Juha, Libor

    2009-01-01

    Roč. 54, č. 2 (2009), s. 439-444 ISSN 1434-6060 R&D Projects: GA AV ČR KAN300100702; GA ČR GA202/05/2316; GA MŠk(CZ) LC528; GA ČR GC202/07/J008; GA MŠk(CZ) 7E08094; GA MŠk(CZ) 7E09092 EU Projects: European Commission(XE) 506350 - LASERLAB-EUROPE Institutional research plan: CEZ:AV0Z10100523 Keywords : x-ray laser * laser ablation * microstruturing * dense plasma probing Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.420, year: 2009

  12. X-ray diffraction studies of the structure and orientations of thiophene and fluorenone based molecule

    International Nuclear Information System (INIS)

    Porzio, William; Pasini, Mariacecilia; Destri, Silvia; Giovanella, Umberto; Fontaine, Philippe

    2006-01-01

    The crystal structure of a conjugated molecule containing thiophene and fluorenone residues has been determined from powder X-ray diffraction (XRD). Thin films ( -5 Pa) onto oxidized silicon substrates, are oriented along with different crystallographic directions. A comparison of XRD in both Grazing Incidence and Bragg-Brentano geometries allowed to perform a quantitative analysis of the various orientations. This approach is generally applicable in the case of multi-oriented films. The results fully account for the poor performance of this molecule in p-type field effect transistor devices

  13. Research on tomato seed vigor based on X-ray digital image

    Science.gov (United States)

    Zhao, Xueguan; Gao, Yuanyuan; Wang, Xiu; Li, Cuiling; Wang, Songlin; Feng, Qinghun

    2016-10-01

    Seed size, interior abnormal and damage of the tomato seeds will affect the germination. The purpose of this paper was to study the relationship between the internal morphology, seed size and seed germination of tomato. The preprocessing algorithm of X-ray image of tomato seeds was studied, and the internal structure characteristics of tomato seeds were extracted by image processing algorithm. By developing the image processing software, the cavity area between embryo and endosperm and the whole seed zone were determined. According to the difference of area of embryo and endosperm and Internal structural condition, seeds were divided into six categories, Respectively for three kinds of tomato seed germination test, the relationship between seed vigor and seed size , internal free cavity was explored through germination experiment. Through seedling evaluation test found that X-ray image analysis provide a perfect view of the inside part of the seed and seed morphology research methods. The larger the area of the endosperm and the embryo, the greater the probability of healthy seedlings sprout from the same size seeds. Mechanical damage adversely effects on seed germination, deterioration of tissue prone to produce week seedlings and abnormal seedlings.

  14. X-ray photoelectron spectroscopic study of catalyst based zinc oxide thin films

    International Nuclear Information System (INIS)

    Shinde, S.S.; Rajpure, K.Y.

    2011-01-01

    Research highlights: → The two step approach for quantitative XPS analysis of ZnO films has been reported. → Surface composition and chemical states of F and In/ZnO catalysts have been studied. → The chemical shifts and Auger parameter have been investigated. - Abstract: X-ray photoelectron spectroscopy (XPS) is a powerful tool for surface and interface analysis, providing an elemental composition of surfaces and the local chemical environment of adsorbed species. The surface composition and chemical states of the F/ZnO and In/ZnO catalysts deposited using spray technique have been studied by high resolution and high sensitivity X-ray photoelectron spectroscopy. A hybrid multiline method is proposed for quantitative XPS analysis that combines the first principles approach with the experimental determination of overall response function. The chemical shifts of XPS core lines for Zn (2P 3/2 , F 1s and In 3d) and Auger parameter for zinc (β Zn = 2012.6, 2011.48 eV for F/ZnO and In/ZnO, respectively) have been calculated. The results have been used to determine the bond iconicity (0.55).

  15. Windowless microfluidic platform based on capillary burst valves for high intensity x-ray measurements

    International Nuclear Information System (INIS)

    Vig, Asger Laurberg; Enevoldsen, Nikolaj; Thilsted, Anil Haraksingh; Eriksen, Johan; Kristensen, Anders; Haldrup, Kristoffer; Feidenhans'l, Robert; Nielsen, Martin Meedom

    2009-01-01

    We propose and describe a microfluidic system for high intensity x-ray measurements. The required open access to a microfluidic channel is provided by an out-of-plane capillary burst valve (CBV). The functionality of the out-of-plane CBV is characterized with respect to the diameter of the windowless access hole, ranging from 10 to 130 μm. Maximum driving pressures from 22 to 280 mbar corresponding to refresh rates of the exposed sample from 300 Hz to 54 kHz is demonstrated. The microfluidic system is tested at beamline ID09b at the ESRF synchrotron radiation facility in Grenoble, and x-ray scattering measurements are shown to be feasible and to require only very limited amounts of sample, <1 ml/h of measurements without recapturing of sample. With small adjustments of the present chip design, scattering angles up to 30 deg. can be achieved without shadowing effects and integration on-chip mixing and spectroscopy appears straightforward.

  16. X-ray screening materials

    International Nuclear Information System (INIS)

    Wardley, R.B.

    1981-01-01

    This invention relates to x-ray screening materials and especially to materials in sheet form for use in the production of, for example, protective clothing such as aprons and lower back shields, curtains, mobile screens and suspended shields. The invention is based on the observation that x-ray screening materials in sheet form having greater flexiblity than the hitherto known x-ray screening materials of the same x-ray absorber content can be produced if, instead of using a single sheet of filled sheet material of increased thickness, one uses a plurality of sheets of lesser thickness together forming a laminar material of the desired thickness and one bonds the individual sheets together at their edges and, optionally, at other spaced apart points away from the edges thereby allowing one sheet to move relative to another. (U.K.)

  17. Measured and calculated K-fluorescence effects on the MTF of an amorphous-selenium based CCD x-ray detector.

    Science.gov (United States)

    Hunter, David M; Belev, George; Kasap, Safa; Yaffe, Martin J

    2012-02-01

    Theoretical reasoning suggests that direct conversion digital x-ray detectors based upon photoconductive amorphous-selenium (a-Se) could attain very high values of the MTF (modulation transfer function) at spatial frequencies well beyond 20 cycles mm(-1). One of the fundamental factors affecting resolution loss, particularly at x-ray energies just above the K-edge of selenium (12.66 keV), is the K-fluorescence reabsorption mechanism, wherein energy can be deposited in the detector at locations laterally displaced from the initial x-ray interaction site. This paper compares measured MTF changes above and below the Se K-edge of a CCD based a-Se x-ray detector with theoretical expectations. A prototype 25 μm sampling pitch (Nyquist frequency = 20 cycles mm(-1), 200 μm thick a-Se layer based x-ray detector, utilizing a specialized CCD readout device (200 × 400 area array), was used to make edge images with monochromatic x-rays above and below the K-edge of Se. A vacuum double crystal monochromator, exposed to polychromatic x-rays from a synchrotron, formed the monochromatic x-ray source. The monochromaticity of the x-rays was 99% or better. The presampling MTF was determined using the slanted edge method. The theory modeling the MTF performance of the detector includes the basic x-ray interaction physics in the a-Se layer as well as effects related to the operation of the CCD and charge trapping at a blocking layer present at the CCD/a-Se interface. The MTF performance of the prototype a-Se CCD was reduced from the theoretical value prescribed by the basic Se x-ray interaction physics, principally by the presence of a blocking layer. Nevertheless, the K-fluorescence reduction in the MTF was observed, approximately as predicted by theory. For the CCD prototype detector, at five cycles mm(-1), there was a 14% reduction of the MTF, from a value of 0.7 below the K-edge of Se, to 0.6 just above the K-edge. The MTF of an a-Se x-ray detector has been measured using

  18. Flash X-ray

    International Nuclear Information System (INIS)

    Sato, Eiichi

    2003-01-01

    Generation of quasi-monochromatic X-ray by production of weakly ionized line plasma (flash X-ray), high-speed imaging by the X-ray and high-contrast imaging by the characteristic X-ray absorption are described. The equipment for the X-ray is consisted from the high-voltage power supply and condenser, turbo molecular pump, and plasma X-ray tube. The tube has a long linear anticathode to produce the line plasma and flash X-ray at 20 kA current at maximum. X-ray spectrum is measured by the imaging plate equipped in the computed radiography system after diffracted by a LiF single crystal bender. Cu anticathode generates sharp peaks of K X-ray series. The tissue images are presented for vertebra, rabbit ear and heart, and dog heart by X-ray fluoroscopy with Ce anticathode. Generation of K-orbit characteristic X-ray with extremely low bremsstrahung is to be attempted for medical use. (N.I.)

  19. Cardiac motion correction based on partial angle reconstructed images in x-ray CT

    International Nuclear Information System (INIS)

    Kim, Seungeon; Chang, Yongjin; Ra, Jong Beom

    2015-01-01

    Purpose: Cardiac x-ray CT imaging is still challenging due to heart motion, which cannot be ignored even with the current rotation speed of the equipment. In response, many algorithms have been developed to compensate remaining motion artifacts by estimating the motion using projection data or reconstructed images. In these algorithms, accurate motion estimation is critical to the compensated image quality. In addition, since the scan range is directly related to the radiation dose, it is preferable to minimize the scan range in motion estimation. In this paper, the authors propose a novel motion estimation and compensation algorithm using a sinogram with a rotation angle of less than 360°. The algorithm estimates the motion of the whole heart area using two opposite 3D partial angle reconstructed (PAR) images and compensates the motion in the reconstruction process. Methods: A CT system scans the thoracic area including the heart over an angular range of 180° + α + β, where α and β denote the detector fan angle and an additional partial angle, respectively. The obtained cone-beam projection data are converted into cone-parallel geometry via row-wise fan-to-parallel rebinning. Two conjugate 3D PAR images, whose center projection angles are separated by 180°, are then reconstructed with an angular range of β, which is considerably smaller than a short scan range of 180° + α. Although these images include limited view angle artifacts that disturb accurate motion estimation, they have considerably better temporal resolution than a short scan image. Hence, after preprocessing these artifacts, the authors estimate a motion model during a half rotation for a whole field of view via nonrigid registration between the images. Finally, motion-compensated image reconstruction is performed at a target phase by incorporating the estimated motion model. The target phase is selected as that corresponding to a view angle that is orthogonal to the center view angles of

  20. Cardiac motion correction based on partial angle reconstructed images in x-ray CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seungeon; Chang, Yongjin; Ra, Jong Beom, E-mail: jbra@kaist.ac.kr [Department of Electrical Engineering, KAIST, Daejeon 305-701 (Korea, Republic of)

    2015-05-15

    Purpose: Cardiac x-ray CT imaging is still challenging due to heart motion, which cannot be ignored even with the current rotation speed of the equipment. In response, many algorithms have been developed to compensate remaining motion artifacts by estimating the motion using projection data or reconstructed images. In these algorithms, accurate motion estimation is critical to the compensated image quality. In addition, since the scan range is directly related to the radiation dose, it is preferable to minimize the scan range in motion estimation. In this paper, the authors propose a novel motion estimation and compensation algorithm using a sinogram with a rotation angle of less than 360°. The algorithm estimates the motion of the whole heart area using two opposite 3D partial angle reconstructed (PAR) images and compensates the motion in the reconstruction process. Methods: A CT system scans the thoracic area including the heart over an angular range of 180° + α + β, where α and β denote the detector fan angle and an additional partial angle, respectively. The obtained cone-beam projection data are converted into cone-parallel geometry via row-wise fan-to-parallel rebinning. Two conjugate 3D PAR images, whose center projection angles are separated by 180°, are then reconstructed with an angular range of β, which is considerably smaller than a short scan range of 180° + α. Although these images include limited view angle artifacts that disturb accurate motion estimation, they have considerably better temporal resolution than a short scan image. Hence, after preprocessing these artifacts, the authors estimate a motion model during a half rotation for a whole field of view via nonrigid registration between the images. Finally, motion-compensated image reconstruction is performed at a target phase by incorporating the estimated motion model. The target phase is selected as that corresponding to a view angle that is orthogonal to the center view angles of

  1. Linear Fresnel zone plate based two-state alignment system for 0.25 micron x-ray lithography

    International Nuclear Information System (INIS)

    Chen, G.

    1993-01-01

    X-ray lithography has proven to be a cost effective and promising technique for fabricating Integrated Circuits (ICs) with minimum feature sizes of less than 0.25 μm. Since IC fabrication is a multilevel process, to preserve the functionality of devices, circuit patterns printed at each lithography level must match existing patterns on the wafer with an accuracy of less than 1/3 ∼ 1/5 of the minimum feature size. An alignment system is used to position the mask relative to the wafer so that mask circuit patterns can be printed on the wafer at the designed position. As the minimum printed feature size shrinks, the overlay requirements of a lithography tool become more stringent. A stepper for 0.25 μm feature device fabrication requires an overlay accuracy of 0.075 μm, of which only 0.05 μm (mean + 3σ) is allocated to its alignment system. This thesis presents the development of a linear Fresnel zone late based two-state alignment (TSA) method for a 0.25 μm x-ray lithography tool. The authors first analyze the overlay requirement in a lithography process and the error allocation to the alignment system for a 0.25 μ feature x-ray lithography tool. They then describe the principle of the two-state alignment, its computer simulation and the optimal alignment mark design. They carried out an optical bench test for the one-axes alignment setup and experimentally evaluated the performance of the system. They developed a three-axes TSA system and integrated the system with the ES-3 x-ray beamline to construct the CXrL aligner, an experimental x-ray exposure system in CXrL. They measured the alignment accuracy of the exposure system to be better than 0.035 μm (3σ) on both metal and dielectric alignment mark substrates. They also studied the effect of processing coatings on the alignment signal with different wafer mark substrates. They successfully printed the 0.5 μm gate level patterns for the first NMOS test chip at CXrL

  2. One dimensional detector for X-ray diffraction with superior energy resolution based on silicon strip detector technology

    International Nuclear Information System (INIS)

    Dąbrowski, W; Fiutowski, T; Wiącek, P; Fink, J; Krane, H-G

    2012-01-01

    1-D position sensitive X-ray detectors based on silicon strip detector technology have become standard instruments in X-ray diffraction and are available from several vendors. As these devices have been proven to be very useful and efficient further improvement of their performance is investigated. The silicon strip detectors in X-ray diffraction are primarily used as counting devices and the requirements concerning the spatial resolution, dynamic range and count rate capability are of primary importance. However, there are several experimental issues in which a good energy resolution is important. The energy resolution of silicon strip detectors is limited by the charge sharing effects in the sensor as well as by noise of the front-end electronics. The charge sharing effects in the sensor and various aspects of the electronics, including the baseline fluctuations, which affect the energy resolution, have been analyzed in detail and a new readout concept has been developed. A front-end ASIC with a novel scheme of baseline restoration and novel interstrip logic circuitry has been designed. The interstrip logic is used to reject the events resulting in significant charge sharing between neighboring strips. At the expense of rejecting small fraction of photons entering the detector one can obtain single strip energy spectra almost free of charge sharing effects. In the paper we present the design considerations and measured performance of the detector being developed. The electronic noise of the system at room temperature is typically of the order of 70 el rms for 17 mm long silicon strips and a peaking time of about 1 μs. The energy resolution of 600 eV FWHM has been achieved including the non-reducible charge sharing effects and the electronic noise. This energy resolution is sufficient to address a common problem in X-ray diffraction, i.e. electronic suppression of the fluorescence radiation from samples containing iron or cobalt while irradiated with 8.04 ke

  3. Fabrication of applicator system of miniature X-ray tube based on carbon nanotubes for a skin cancer therapy

    International Nuclear Information System (INIS)

    Park, Han Beom; Kim, Hyun Jin; Lee, Ju Hyuk; Ha, Jun Mok; Cho, Sung Oh

    2016-01-01

    A miniature X-ray tube is a small X-ray generation device generally with a diameter of less than 10 mm. Because of the feasible installation in a spatially constrained area and the possibility of electrical on/off control, miniature X-ray tubes can be widely used for nondestructive X-ray radiography, hand held X-ray spectrometers, electric brachytherapy, and interstitial or intracavitary radiation therapy or imaging with the substitution of radioactive isotopes. Miniature X-ray tubes have been developed mostly using thermionic electron sources or secondary X-ray emission. The X-ray tube show excellent field emission properties and good X-ray spectrum. Also, the flattening filter was made to irradiate uniformly. The X-ray dose radial uniformities between installed flattening filter and non-installed flattening filter were measured. When flattening filter is equipped, X-ray uniformity was improved from higher than 20% to lower than 10%. As a result, the fabricated applicator system of the miniature X-ray tube using optimized flattening filter exhibited fairly excellent properties

  4. Radiomics-based differentiation of lung disease models generated by polluted air based on X-ray computed tomography data

    International Nuclear Information System (INIS)

    Szigeti, Krisztián; Szabó, Tibor; Korom, Csaba; Czibak, Ilona; Horváth, Ildikó; Veres, Dániel S.; Gyöngyi, Zoltán; Karlinger, Kinga; Bergmann, Ralf; Pócsik, Márta; Budán, Ferenc; Máthé, Domokos

    2016-01-01

    Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann–Whitney post hoc (MWph) tests were used. Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas. The online version of this article (doi:10.1186/s12880-016-0118-z) contains supplementary material, which is available to authorized users

  5. Substrate and Passivation Techniques for Flexible Amorphous Silicon-Based X-ray Detectors.

    Science.gov (United States)

    Marrs, Michael A; Raupp, Gregory B

    2016-07-26

    Flexible active matrix display technology has been adapted to create new flexible photo-sensing electronic devices, including flexible X-ray detectors. Monolithic integration of amorphous silicon (a-Si) PIN photodiodes on a flexible substrate poses significant challenges associated with the intrinsic film stress of amorphous silicon. This paper examines how altering device structuring and diode passivation layers can greatly improve the electrical performance and the mechanical reliability of the device, thereby eliminating one of the major weaknesses of a-Si PIN diodes in comparison to alternative photodetector technology, such as organic bulk heterojunction photodiodes and amorphous selenium. A dark current of 0.5 pA/mm² and photodiode quantum efficiency of 74% are possible with a pixelated diode structure with a silicon nitride/SU-8 bilayer passivation structure on a 20 µm-thick polyimide substrate.

  6. Maximum entropy based reconstruction of soft X ray emissivity profiles in W7-AS

    International Nuclear Information System (INIS)

    Ertl, K.; Linden, W. von der; Dose, V.; Weller, A.

    1996-01-01

    The reconstruction of 2-D emissivity profiles from soft X ray tomography measurements constitutes a highly underdetermined and ill-posed inversion problem, because of the restricted viewing access, the number of chords and the increased noise level in most plasma devices. An unbiased and consistent probabilistic approach within the framework of Bayesian inference is provided by the maximum entropy method, which is independent of model assumptions, but allows any prior knowledge available to be incorporated. The formalism is applied to the reconstruction of emissivity profiles in an NBI heated plasma discharge to determine the dependence of the Shafranov shift on β, the reduction of which was a particular objective in designing the advanced W7-AS stellarator. (author). 40 refs, 7 figs

  7. Quantitative analysis of flow processes in a sand using synchrotron-based X-ray microtomography

    DEFF Research Database (Denmark)

    Wildenschild, Dorthe; Hopmans, J.W.; Rivers, M.L.

    2005-01-01

    been of a mostly qualitative nature and no experiments have been presented in the existing literature where a truly quantitative approach to investigating the multiphase flow process has been taken, including a thorough image-processing scheme. The tomographic images presented here show, both......Pore-scale multiphase flow experiments were developed to nondestructively visualize water flow in a sample of porous material using X-ray microtomography. The samples were exposed to similar boundary conditions as in a previous investigation, which examined the effect of initial flow rate...... by qualitative comparison and quantitative analysis in the form of a nearest neighbor analysis, that the dynamic effects seen in previous experiments are likely due to the fast and preferential drainage of large pores in the sample. Once a continuous drained path has been established through the sample, further...

  8. Feature-based analysis for quality assessment of x-ray computed tomography measurements

    International Nuclear Information System (INIS)

    Nardelli, Vitor C; Arenhart, Francisco A; Donatelli, Gustavo D; Porath, Maurício C; Niggemann, Christian; Schmitt, Robert

    2012-01-01

    This paper presents an approach to assess the quality of the data extracted with computed tomography (CT) measuring systems to perform geometrical evaluations. The approach consists in analyzing the error features introduced by the CT measuring system during the extraction operation. The analysis of the features is performed qualitatively (using graphical analysis tools) and/or quantitatively (by means of the root-mean-square deviation parameter of the error features). The approach was used to analyze four sets of measurements performed with an industrial x-ray cone beam CT measuring system. Three test parts were used in the experiments: a high accuracy manufacturing multi-wave standard, a calibrated step cylinder and a calibrated production part. The results demonstrate the usefulness of the approach to gain knowledge on CT measuring processes and improve the quality of CT geometrical evaluations. Advantages and limitations of the approach are discussed. (paper)

  9. Transferring x-ray based automated threat detection between scanners with different energies and resolution

    Science.gov (United States)

    Caldwell, M.; Ransley, M.; Rogers, T. W.; Griffin, L. D.

    2017-10-01

    A significant obstacle to developing high performance Deep Learning algorithms for Automated Threat Detection (ATD) in security X-ray imagery, is the difficulty of obtaining large training datasets. In our previous work, we circumvented this problem for ATD in cargo containers, using Threat Image Projection and data augmentation. In this work, we investigate whether data scarcity for other modalities, such as parcels and baggage, can be ameliorated by transforming data from one domain so that it approximates the appearance of another. We present an ontology of ATD datasets to assess where transfer learning may be applied. We define frameworks for transfer at the training and testing stages, and compare the results for both methods against ATD where a common data source is used for training and testing. Our results show very poor transfer, which we attribute to the difficulty of accurately matching the blur and contrast characteristics of different scanners.

  10. Ways to discharge-based soft X-ray lasers with the wavelength <15 nm

    Czech Academy of Sciences Publication Activity Database

    Koláček, Karel; Schmidt, Jiří; Prukner, Václav; Frolov, Oleksandr; Štraus, Jaroslav

    2008-01-01

    Roč. 26, č. 2 (2008), s. 167-178 ISSN 0263-0346. [International Conference on the Frontiers of Plasma Physics and Technology/3rd./. Bangkok, Thailand, 05.03.2007-09.03.2007] R&D Projects: GA ČR GA202/06/1324; GA MŠk LA08024; GA AV ČR KAN300100702; GA AV ČR KJB100430702 Institutional research plan: CEZ:AV0Z20430508 Keywords : soft X-ray * laser * fast high-current capillary discharge * exploding wire in water * focused shock wave in water Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 4.420, year: 2008

  11. X-ray elastic constants in textured Zr-base materials

    International Nuclear Information System (INIS)

    Ortiz, M.; Pochettino, A.A.; Lebrun, J.L.; Maeder, G.

    1993-01-01

    A general method for the calculation of the X-ray elastic constants (XREC) for textured hexagonal close-packed (hcp) materials was developed by using the orientation distribution function (ODF) and the Reuss hypothesis. This method was applied to textured zirconium (Zr) sheets and zircaloy 4 (Zry 4) extruded tubes. For these samples, where the elastic anisotropy is not very strong, an 'isotropic approximation' method is proposed using the ODF data. In that case, the classical XREC 1/2S 2 and S, values are calculated and experimentally verified for (10 bar 14) diffracting planes. Theoretical XREC values are also given for different (hkil) that could be chosen according to the experimental conditions, considering texture effects on diffracting peak intensities

  12. Thermometric- and Acoustic-Based Beam Power Monitor for Ultra-Bright X-Rays

    International Nuclear Information System (INIS)

    2010-01-01

    A design for an average beam power monitor for ultra-bright X-ray sources is proposed that makes simultaneous use of calorimetry and radiation acoustics. Radiation incident on a solid target will induce heating and ultrasonic vibrations, both of which may be measured to give a fairly precise value of the beam power. The monitor is intended for measuring ultra-bright Free-Electron Laser (FEL) X-ray beams, for which traditional monitoring technologies such as photo-diodes or scintillators are unsuitable. The monitor consists of a Boron Carbide (B 4 C) target designed to absorb most of the incident beam's energy. Resistance temperature detectors (RTD) and piezoelectric actuators are mounted on the outward faces of the target to measure the temperature changes and ultrasonic vibrations induced by the incident beam. The design was tested using an optical pulsed beam (780 nm, 120 and 360 Hz) from a Ti:sapphire oscillator at several energies between 0.8 and 2.6 mJ. The RTDs measured an increase in temperature of about 10 K over a period of several minutes. The piezoelectric sensors recorded ringing acoustic oscillations at 580 ± 40 kHz. Most importantly, the amplitude of the acoustic signals was observed to scale linearly with beam power up to 2 mJ of pulse energy. Above this pulse energy, the vibrational signals became nonlinear. Several causes for this nonlinearity are discussed, including amplifier saturation and piezoelectric saturation. Despite this nonlinearity, these measurements demonstrate the feasibility of such a beam power measurement device. The advantage of two distinct measurements (acoustic and thermometric) provides a useful method of calibration that is unavailable to current LCLS diagnostics tools.

  13. X-ray astronomy

    International Nuclear Information System (INIS)

    Culhane, J.L.; Sanford, P.W.

    1981-01-01

    X-ray astronomy has been established as a powerful means of observing matter in its most extreme form. The energy liberated by sources discovered in our Galaxy has confirmed that collapsed stars of great density, and with intense gravitational fields, can be studied by making observations in the X-ray part of the electromagnetic spectrum. The astronomical objects which emit detectable X-rays include our own Sun and extend to quasars at the edge of the Universe. This book describes the history, techniques and results obtained in the first twenty-five years of exploration. Space rockets and satellites are essential for carrying the instruments above the Earth's atmosphere where it becomes possible to view the X-rays from stars and nebulae. The subject is covered in chapters, entitled: the birth of X-ray astronomy; the nature of X-radiation; X-rays from the Sun; solar-flare X-rays; X-rays from beyond the solar system; supernovae and their remnants; X-rays from binary stars; white dwarfs and neutron stars; black holes; X-rays from galaxies and quasars; clusters of galaxies; the observatories of the future. (author)

  14. Workshop on the coupling of synchrotron radiation IR and X-rays with tip based scanning probe microscopies X-TIP

    Energy Technology Data Exchange (ETDEWEB)

    Comin, F.; Martinez-Criado, G.; Mundboth, K.; Susini, J. [European Synchrotron Radiation Facility (ESRF), 38 - Grenoble (France); Purans, J.; Sammelselg, V. [Tartu Univ. (Estonia); Chevrier, J.; Huant, S. [Universite Joseph-Fourier, Grenoble I, LEPES, 38 (France); Hamilton, B. [School of Electrical Engineering and Electronics, Manchester (United Kingdom); Saito, A. [Osaka Univ., RIKEN/SPring8 (Japan); Dhez, O. [OGG, INFM/CNR, 38 - Grenoble (France); Brocklesby, W.S. [Southampton Univ., Optoelectronics Research Centre (United Kingdom); Alvarez-Prado, L.M. [Ovieado, Dept. de Fisica (Spain); Kuzmin, A. [Institute of Solid State Physics - Riga (Latvia); Pailharey, D. [CRMC-N - CNRS, 13 - Marseille (France); Tonneau, D. [CRMCN - Faculte des sciences de Luminy, 13 - Marseille (France); Chretien, P. [Laboratoire de Genie Electrique de Paris, 75 - Paris (France); Cricenti, A. [ISM-CNR, Rome (Italy); DeWilde, Y. [ESPCI, 75 - Paris (France)

    2005-07-01

    The coupling of scanning probe microscopy (SPM) with synchrotron radiation is attracting increasing attention from nano-science community. By combining these 2 tools one can visualize, for example, the sample nano-structure prior to any X-ray characterization. Coupled with focusing devices or independently, SPM can provide spatial resolution below the optical limits. Furthermore, the possibility of employing SPM to manipulate nano-objects under X-ray beams is another exciting perspective. This document gathers the transparencies of 6 of the presentations made at the workshop: 1) the combination of atomic force microscopy and X-ray beam - experimental set-up and objectives; 2) the combination of scanning probe microscope and X-rays for detection of electrons; 3) towards soft X-ray scanning microscopy using tapered capillaries and laser-based high harmonic sources; 4) near-field magneto-optical microscopy; 5) near-field scanning optical microscopy - a brief overview -; and 6) from aperture-less near-field optical microscopy to infra-red near-field night vision. 4 posters entitled: 1) development of laboratory setup for X-ray/AFM experiments, 2) towards X-ray diffraction on single islands, 3) nano-XEOL using near-field detection, and 4) local collection with a STM tip of photoelectrons emitted by a surface irradiated by visible of UV laser beam, are included in the document.

  15. Workshop on the coupling of synchrotron radiation IR and X-rays with tip based scanning probe microscopies X-TIP

    International Nuclear Information System (INIS)

    Comin, F.; Martinez-Criado, G.; Mundboth, K.; Susini, J.; Purans, J.; Sammelselg, V.; Chevrier, J.; Huant, S.; Hamilton, B.; Saito, A.; Dhez, O.; Brocklesby, W.S.; Alvarez-Prado, L.M.; Kuzmin, A.; Pailharey, D.; Tonneau, D.; Chretien, P.; Cricenti, A.; DeWilde, Y.

    2005-01-01

    The coupling of scanning probe microscopy (SPM) with synchrotron radiation is attracting increasing attention from nano-science community. By combining these 2 tools one can visualize, for example, the sample nano-structure prior to any X-ray characterization. Coupled with focusing devices or independently, SPM can provide spatial resolution below the optical limits. Furthermore, the possibility of employing SPM to manipulate nano-objects under X-ray beams is another exciting perspective. This document gathers the transparencies of 6 of the presentations made at the workshop: 1) the combination of atomic force microscopy and X-ray beam - experimental set-up and objectives; 2) the combination of scanning probe microscope and X-rays for detection of electrons; 3) towards soft X-ray scanning microscopy using tapered capillaries and laser-based high harmonic sources; 4) near-field magneto-optical microscopy; 5) near-field scanning optical microscopy - a brief overview -; and 6) from aperture-less near-field optical microscopy to infra-red near-field night vision. 4 posters entitled: 1) development of laboratory setup for X-ray/AFM experiments, 2) towards X-ray diffraction on single islands, 3) nano-XEOL using near-field detection, and 4) local collection with a STM tip of photoelectrons emitted by a surface irradiated by visible of UV laser beam, are included in the document

  16. In situ analyses of Ag speciation in tissues of cucumber and wheat using synchrotron-based X-ray absorption spectroscopy

    Data.gov (United States)

    U.S. Environmental Protection Agency — In situ analyses of Ag speciation in tissues of cucumber and wheat using synchrotron-based X-ray absorption spectroscopy showing spectral fitting and linear...

  17. Exposure to ionizing radiation during dental X-rays is not associated with risk of developing meningioma: a meta-analysis based on seven case-control studies.

    Science.gov (United States)

    Xu, Ping; Luo, Hong; Huang, Guang-Lei; Yin, Xin-Hai; Luo, Si-Yang; Song, Ju-Kun

    2015-01-01

    Many observational studies have found that exposure to dental X-rays is associated with the risk of development of meningioma. However, these findings are inconsistent. We conducted a meta-analysis to assess the relationship between exposure to dental X-rays and the risk of development of meningioma. The PubMed and EMBASE databases were searched to identify eligible studies. Summary odds ratio (OR) estimates and 95% confidence intervals (95% CIs) were used to compute the risk of meningioma development according to heterogeneity. Subgroup and sensitivity analyses were performed to further explore the potential heterogeneity. Finally, publication bias was assessed. Seven case-control studies involving 6,174 patients and 19,459 controls were included in the meta-analysis. Neither exposure to dental X-rays nor performance of full-mouth panorex X-rays was associated with an increased risk of development of meningioma (overall: OR, 0.97; 95% CI, 0.70-1.32; dental X-rays: OR, 1.05; 95% CI, 0.89-1.25; panorex X-rays: OR, 1.01; 95% CI, 0.76-1.34). However, exposure to bitewing X-rays was associated with a slightly increased risk of development of meningioma (OR, 1.73; 95% CI, 1.28-2.34). Similar results were obtained in the subgroup and sensitivity analyses. Little evidence of publication bias was observed. Based on the currently limited data, there is no association between exposure to dental X-rays and the risk of development of meningioma. However, these results should be cautiously interpreted because of the heterogeneity among studies. Additional large, high-quality clinical trials are needed to evaluate the association between exposure to dental X-rays and the risk of development of meningioma.

  18. Exposure to ionizing radiation during dental X-rays is not associated with risk of developing meningioma: a meta-analysis based on seven case-control studies.

    Directory of Open Access Journals (Sweden)

    Ping Xu

    Full Text Available Many observational studies have found that exposure to dental X-rays is associated with the risk of development of meningioma. However, these findings are inconsistent. We conducted a meta-analysis to assess the relationship between exposure to dental X-rays and the risk of development of meningioma.The PubMed and EMBASE databases were searched to identify eligible studies. Summary odds ratio (OR estimates and 95% confidence intervals (95% CIs were used to compute the risk of meningioma development according to heterogeneity. Subgroup and sensitivity analyses were performed to further explore the potential heterogeneity. Finally, publication bias was assessed.Seven case-control studies involving 6,174 patients and 19,459 controls were included in the meta-analysis. Neither exposure to dental X-rays nor performance of full-mouth panorex X-rays was associated with an increased risk of development of meningioma (overall: OR, 0.97; 95% CI, 0.70-1.32; dental X-rays: OR, 1.05; 95% CI, 0.89-1.25; panorex X-rays: OR, 1.01; 95% CI, 0.76-1.34. However, exposure to bitewing X-rays was associated with a slightly increased risk of development of meningioma (OR, 1.73; 95% CI, 1.28-2.34. Similar results were obtained in the subgroup and sensitivity analyses. Little evidence of publication bias was observed.Based on the currently limited data, there is no association between exposure to dental X-rays and the risk of development of meningioma. However, these results should be cautiously interpreted because of the heterogeneity among studies. Additional large, high-quality clinical trials are needed to evaluate the association between exposure to dental X-rays and the risk of development of meningioma.

  19. Using Synchrotron-based X-ray Absorption Spectrometry to Identify the Arsenic Chemical Forms in Mine Waste Materials

    International Nuclear Information System (INIS)

    Matanitobua, Vitukawalu P.; Noller, Barry N.; Chiswell, Barry; Ng, Jack C.; Bruce, Scott L.; Huang, Daphne; Riley, Mark; Harris, Hugh H.

    2007-01-01

    X-ray Absorption Near Edge Spectroscopy (XANES) gives arsenic form directly in the solid phase and has lower detection limits than extraction techniques. An important and common application of XANES is to use the shift of the edge position to determine the valence state. XANES speciation analysis is based on fitting linear combinations of known spectra from model compounds to determine the ratios of valence states and/or phases present. As(V)/As(III) ratios were determined for various Australian mine waste samples and dispersed mine waste samples from river/creek sediments in Vatukoula, Fiji

  20. A new method of explosive detection based on dual-energy X-ray technology and forward-scattering

    International Nuclear Information System (INIS)

    Zhao Kun; Li Jianmin

    2004-01-01

    Based on dual-energy X-ray technology combined with forward-scattering, a brand new explosive detection method is presented. Dual-energy technology can give the information on the effective atomic number (Z eff ) of an irradiated component, while the intensity of the forward scattered photons can reveal the density information according to our research. Therefore, the existence of the explosive can be effectively identified by combining these two characteristic quantities. Compared with the earlier inspection approaches, the new one has a series of particular advantages, such as high detection rate, low false alarm rate, automatic alarm and so forth. The project is ongoing. (authors)

  1. The status of Tsukuba BNCT trial: BPA-based boron neutron capture therapy combined with X-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, T., E-mail: tetsu_tsukuba@yahoo.co.jp [Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan)] [Department of Radiation Oncology, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan); Nakai, K. [Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan); Nariai, T. [Department of Neurosurgery, Tokyo Medical and Dental University, Yushima 1-5-45, Bunkyo-ku, Tokyo (Japan); Kumada, H.; Okumura, T.; Mizumoto, M.; Tsuboi, K. [Department of Radiation Oncology, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan); Zaboronok, A.; Ishikawa, E.; Aiyama, H.; Endo, K.; Takada, T.; Yoshida, F.; Shibata, Y.; Matsumura, A. [Department of Neurosurgery, Graduate School of Comprehensive Human Science, University of Tsukuba, Tennodai 1-1-1, Tsukuba (Japan)

    2011-12-15

    The phase II trial has been prepared to assess the effectiveness of BPA (250 mg/kg)-based NCT combined with X-ray irradiation and temozolomide (75 mg/m{sup 2}) for the treatment of newly diagnosed GBM. BPA uptake is determined by {sup 18}F-BPA-PET and/or {sup 11}C-MET-PET, and a tumor with the lesion to normal ratio of 2 or more is indicated for BNCT. The maximum normal brain point dose prescribed was limited to 13.0 Gy or less. Primary end point is overall survival.

  2. Phase-based x-ray scattering—A possible method to detect cancer cells in a very early stage

    Energy Technology Data Exchange (ETDEWEB)

    Feye-Treimer, U., E-mail: feye-treimer@helmholtz-berlin.de; Treimer, W. [Department of Mathematics, Physics and Chemistry, University of Applied Sciences, D-13353 Berlin, Germany and Joint Department G-GTOMO, Helmholtz Zentrum fuer Materialien und Energie Berlin, D-14109 Berlin (Germany)

    2014-05-15

    Purpose: This theoretical work contains a detailed investigation of the potential and sensitivity of phase-based x-ray scattering for cancer detection in biopsies if cancer is in a very early stage of development. Methods: Cancer cells in their early stage of development differ from healthy ones mainly due to their faster growing cell nuclei and the enlargement of their densities. This growth is accompanied by an altered nucleus–plasma relation for the benefit of the cell nuclei, that changes the physical properties especially the index of refraction of the cell and the one of the cell nuclei. Interaction of radiation with matter is known to be highly sensitive to small changes of the index of refraction of matter; therefore a detection of such changes of volume and density of cell nuclei by means of high angular resolved phase-based scattering of x rays might provide a technique to distinguish malignant cells from healthy ones ifthe cell–cell nucleus system is considered as a coherent phase shifting object. Then one can observe from a thin biopsy which represents a monolayer of cells (no multiple scattering) that phase-based x-ray scattering curves from healthy cells differ from those of cancer cells in their early stage of development. Results: Detailed calculations of x-ray scattering patterns from healthy and cancer cell nuclei yield graphs and numbers with which one can distinguish healthy cells from cancer ones, taking into account that both kinds of cells occur in a tissue within a range of size and density. One important result is the role and the influence of the (lateral) coherence width of the radiation on the scattering curves and the sensitivity of phase-based scattering for cancer detection. A major result is that a larger coherence width yields a larger sensitivity for cancer detection. Further import results are calculated limits for critical sizes and densities of cell nuclei in order to attribute the investigated tissue to be healthy or

  3. Study of Fe-Ni-Si-B alloy and films on its base by X-ray photospectroscopy method

    International Nuclear Information System (INIS)

    Kozlenko, V.G.; Parfenenok, M.A.; Pukhov, I.K.; Shaposhnikov, A.N.; Shirkov, A.V.

    1983-01-01

    By the method of X ray photoelectron spectroscopy the chemical composition of Fe-Ni-Si-B alloy and films on its base prepared by ion-plasma sputtering is investigated. The identity of chemical bonds in film samples and initial target is revealed, realized are in them mostly Fe-B, Ni-C, Si-Si interatomic bonds. It is shown that lono. films contact with atmosphere is the cause of difference of film composition in the near-surface region (up to 100 nm) from its main volume composition

  4. Principle and realization of segmenting contour series algorithm in reverse engineering based on X-ray computerized tomography

    International Nuclear Information System (INIS)

    Wang Yanfang; Liu Li; Yan Yonglian; Shan Baoci; Tang Xiaowei

    2007-01-01

    A new algorithm of segmenting contour series of images is presented, which can achieve three dimension reconstruction with parametric recognition in Reverse Engineering based on X-ray CT. First, in order to get the nested relationship between contours, a method of a certain angle ray is used. Second, for realizing the contour location in one slice, another approach is presented to generate the contour tree by scanning the relevant vector only once. Last, a judge algorithm is put forward to accomplish the contour match between slices by adopting the qualitative and quantitative properties. The example shows that this algorithm can segment contour series of CT parts rapidly and precisely. (authors)

  5. X-ray analysis of phase coexistence and electric poling processing in alkaline niobate-based compositions

    International Nuclear Information System (INIS)

    Fu Jian; Zuo Ruzhong; Liu Yi

    2010-01-01

    The characteristic and origin of two-phase coexistence and the content of each phase in typical alkaline niobate-based lead-free compositions were investigated through the refinement of X-ray diffraction peaks and the measurement of dielectric constant versus temperature curves. The diffuse nature of polymorphic phase transition has resulted in the coexistence of two ferroelectric phases within a wide composition and temperature range. As a result, the optimum piezoelectric properties appear in the composition rich in tetragonal phases and there is a remarkable poling temperature effect. Discussions on the difference between morphotropic phase boundary and polymorphic phase boundary were made in combination with the variation of electrical properties.

  6. Real-time x-ray fluoroscopy-based catheter detection and tracking for cardiac electrophysiology interventions

    International Nuclear Information System (INIS)

    Ma Yingliang; Housden, R. James; Razavi, Reza; Rhode, Kawal S.; Gogin, Nicolas; Cathier, Pascal; Gijsbers, Geert; Cooklin, Michael; O'Neill, Mark; Gill, Jaswinder; Rinaldi, C. Aldo

    2013-01-01

    Purpose: X-ray fluoroscopically guided cardiac electrophysiology (EP) procedures are commonly carried out to treat patients with arrhythmias. X-ray images have poor soft tissue contrast and, for this reason, overlay of a three-dimensional (3D) roadmap derived from preprocedural volumetric images can be used to add anatomical information. It is useful to know the position of the catheter electrodes relative to the cardiac anatomy, for example, to record ablation therapy locations during atrial fibrillation therapy. Also, the electrode positions of the coronary sinus (CS) catheter or lasso catheter can be used for road map motion correction.Methods: In this paper, the authors present a novel unified computational framework for image-based catheter detection and tracking without any user interaction. The proposed framework includes fast blob detection, shape-constrained searching and model-based detection. In addition, catheter tracking methods were designed based on the customized catheter models input from the detection method. Three real-time detection and tracking methods are derived from the computational framework to detect or track the three most common types of catheters in EP procedures: the ablation catheter, the CS catheter, and the lasso catheter. Since the proposed methods use the same blob detection method to extract key information from x-ray images, the ablation, CS, and lasso catheters can be detected and tracked simultaneously in real-time.Results: The catheter detection methods were tested on 105 different clinical fluoroscopy sequences taken from 31 clinical procedures. Two-dimensional (2D) detection errors of 0.50 ± 0.29, 0.92 ± 0.61, and 0.63 ± 0.45 mm as well as success rates of 99.4%, 97.2%, and 88.9% were achieved for the CS catheter, ablation catheter, and lasso catheter, respectively. With the tracking method, accuracies were increased to 0.45 ± 0.28, 0.64 ± 0.37, and 0.53 ± 0.38 mm and success rates increased to 100%, 99.2%, and 96

  7. Real-time x-ray fluoroscopy-based catheter detection and tracking for cardiac electrophysiology interventions

    Energy Technology Data Exchange (ETDEWEB)

    Ma Yingliang; Housden, R. James; Razavi, Reza; Rhode, Kawal S. [Division of Imaging Sciences and Biomedical Engineering, King' s College London, London SE1 7EH (United Kingdom); Gogin, Nicolas; Cathier, Pascal [Medisys Research Group, Philips Healthcare, Paris 92156 (France); Gijsbers, Geert [Interventional X-ray, Philips Healthcare, Best 5680 DA (Netherlands); Cooklin, Michael; O' Neill, Mark; Gill, Jaswinder; Rinaldi, C. Aldo [Department of Cardiology, Guys and St. Thomas' Hospitals NHS Foundation Trust, London SE1 7EH (United Kingdom)

    2013-07-15

    Purpose: X-ray fluoroscopically guided cardiac electrophysiology (EP) procedures are commonly carried out to treat patients with arrhythmias. X-ray images have poor soft tissue contrast and, for this reason, overlay of a three-dimensional (3D) roadmap derived from preprocedural volumetric images can be used to add anatomical information. It is useful to know the position of the catheter electrodes relative to the cardiac anatomy, for example, to record ablation therapy locations during atrial fibrillation therapy. Also, the electrode positions of the coronary sinus (CS) catheter or lasso catheter can be used for road map motion correction.Methods: In this paper, the authors present a novel unified computational framework for image-based catheter detection and tracking without any user interaction. The proposed framework includes fast blob detection, shape-constrained searching and model-based detection. In addition, catheter tracking methods were designed based on the customized catheter models input from the detection method. Three real-time detection and tracking methods are derived from the computational framework to detect or track the three most common types of catheters in EP procedures: the ablation catheter, the CS catheter, and the lasso catheter. Since the proposed methods use the same blob detection method to extract key information from x-ray images, the ablation, CS, and lasso catheters can be detected and tracked simultaneously in real-time.Results: The catheter detection methods were tested on 105 different clinical fluoroscopy sequences taken from 31 clinical procedures. Two-dimensional (2D) detection errors of 0.50 {+-} 0.29, 0.92 {+-} 0.61, and 0.63 {+-} 0.45 mm as well as success rates of 99.4%, 97.2%, and 88.9% were achieved for the CS catheter, ablation catheter, and lasso catheter, respectively. With the tracking method, accuracies were increased to 0.45 {+-} 0.28, 0.64 {+-} 0.37, and 0.53 {+-} 0.38 mm and success rates increased to 100%, 99

  8. Real-time, ray casting-based scatter dose estimation for c-arm x-ray system.

    Science.gov (United States)

    Alnewaini, Zaid; Langer, Eric; Schaber, Philipp; David, Matthias; Kretz, Dominik; Steil, Volker; Hesser, Jürgen

    2017-03-01

    Dosimetric control of staff exposure during interventional procedures under fluoroscopy is of high relevance. In this paper, a novel ray casting approximation of radiation transport is presented and the potential and limitation vs. a full Monte Carlo transport and dose measurements are discussed. The x-ray source of a Siemens Axiom Artix C-arm is modeled by a virtual source model using single Gaussian-shaped source. A Geant4-based Monte Carlo simulation determines the radiation transport from the source to compute scatter from the patient, the table, the ceiling and the floor. A phase space around these scatterers stores all photon information. Only those photons are traced that hit a surface of phantom that represents medical staff in the treatment room, no indirect scattering is considered; and a complete dose deposition on the surface is calculated. To evaluate the accuracy of the approximation, both experimental measurements using Thermoluminescent dosimeters (TLDs) and a Geant4-based Monte Carlo simulation of dose depositing for different tube angulations of the C-arm from cranial-caudal angle 0° and from LAO (Left Anterior Oblique) 0°-90° are realized. Since the measurements were performed on both sides of the table, using the symmetry of the setup, RAO (Right Anterior Oblique) measurements were not necessary. The Geant4-Monte Carlo simulation agreed within 3% with the measured data, which is within the accuracy of measurement and simulation. The ray casting approximation has been compared to TLD measurements and the achieved percentage difference was -7% for data from tube angulations 45°-90° and -29% from tube angulations 0°-45° on the side of the x-ray source, whereas on the opposite side of the x-ray source, the difference was -83.8% and -75%, respectively. Ray casting approximation for only LAO 90° was compared to a Monte Carlo simulation, where the percentage differences were between 0.5-3% on the side of the x-ray source where the highest dose

  9. X-ray holography

    International Nuclear Information System (INIS)

    Faigel, G.; Tegze, M.; Belakhovsky, M.; Marchesini, S.; Bortel, G.

    2003-01-01

    In the last decade holographic methods using hard X-rays were developed. They are able to resolve atomic distances, and can give the 3D arrangement of atoms around a selected element. Therefore, hard X-ray holography has potential applications in chemistry, biology and physics. In this article we give a general description of these methods and discuss the developments in the experimental technique. The capabilities of hard X-ray holography are demonstrated by examples

  10. Quantification of root water uptake in soil using X-ray computed tomography and image-based modelling.

    Science.gov (United States)

    Daly, Keith R; Tracy, Saoirse R; Crout, Neil M J; Mairhofer, Stefan; Pridmore, Tony P; Mooney, Sacha J; Roose, Tiina

    2018-01-01

    Spatially averaged models of root-soil interactions are often used to calculate plant water uptake. Using a combination of X-ray computed tomography (CT) and image-based modelling, we tested the accuracy of this spatial averaging by directly calculating plant water uptake for young wheat plants in two soil types. The root system was imaged using X-ray CT at 2, 4, 6, 8 and 12 d after transplanting. The roots were segmented using semi-automated root tracking for speed and reproducibility. The segmented geometries were converted to a mesh suitable for the numerical solution of Richards' equation. Richards' equation was parameterized using existing pore scale studies of soil hydraulic properties in the rhizosphere of wheat plants. Image-based modelling allows the spatial distribution of water around the root to be visualized and the fluxes into the root to be calculated. By comparing the results obtained through image-based modelling to spatially averaged models, the impact of root architecture and geometry in water uptake was quantified. We observed that the spatially averaged models performed well in comparison to the image-based models with <2% difference in uptake. However, the spatial averaging loses important information regarding the spatial distribution of water near the root system. © 2017 John Wiley & Sons Ltd.

  11. Quantitative X-ray Map Analyser (Q-XRMA): A new GIS-based statistical approach to Mineral Image Analysis

    Science.gov (United States)

    Ortolano, Gaetano; Visalli, Roberto; Godard, Gaston; Cirrincione, Rosolino

    2018-06-01

    We present a new ArcGIS®-based tool developed in the Python programming language for calibrating EDS/WDS X-ray element maps, with the aim of acquiring quantitative information of petrological interest. The calibration procedure is based on a multiple linear regression technique that takes into account interdependence among elements and is constrained by the stoichiometry of minerals. The procedure requires an appropriate number of spot analyses for use as internal standards and provides several test indexes for a rapid check of calibration accuracy. The code is based on an earlier image-processing tool designed primarily for classifying minerals in X-ray element maps; the original Python code has now been enhanced to yield calibrated maps of mineral end-members or the chemical parameters of each classified mineral. The semi-automated procedure can be used to extract a dataset that is automatically stored within queryable tables. As a case study, the software was applied to an amphibolite-facies garnet-bearing micaschist. The calibrated images obtained for both anhydrous (i.e., garnet and plagioclase) and hydrous (i.e., biotite) phases show a good fit with corresponding electron microprobe analyses. This new GIS-based tool package can thus find useful application in petrology and materials science research. Moreover, the huge quantity of data extracted opens new opportunities for the development of a thin-section microchemical database that, using a GIS platform, can be linked with other major global geoscience databases.

  12. Practical chemical analysis of Pt and Pd based heterogeneous catalysts with hard X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, H., E-mail: YOSHIKAWA.Hideki@nims.go.jp [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Matolínová, I.; Matolín, V. [Charles University in Prague, Faculty of Mathematics and Physics, V Holešovičkách 2, 18000 Prague 8 (Czech Republic)

    2013-10-15

    Highlights: •Hard X-ray photoelectron spectroscopy (HAXPES) enables interface analysis of catalyst. •HAXPES enables overall analysis of porous film of Pt-doped CeO{sub 2} and related catalyst. •HAXPES enables analysis of trace elements for Pd and Pt{sub 3}Ni nanoparticle catalysts. -- Abstract: Interfacial properties including configuration, porosity, chemical states, and atomic diffusion greatly affect the performance of supported heterogeneous catalysts. Hard X-ray photoelectron spectroscopy (HAXPES) can be used to analyze the interfaces of heterogeneous catalysts because of its large information depth of more than 20 nm. We use HAXPES to examine Pt-doped CeO{sub 2} and related thin film catalysts evaporated on Si, carbon, and carbon nanotube substrates, because Pt-doped CeO{sub 2} has great potential as a noble metal-based heterogeneous catalyst for fuel cells. The HAXPES measurements clarify that the dopant material, substrate material, and surface pretreatment of substrate are important parameters that affect the interfacial properties of Pt-doped CeO{sub 2} and related thin film catalysts. Another advantage of HAXPES measurement of heterogeneous catalysts is that it can be used for chemical analysis of trace elements by detecting photoelectrons from deep core levels, which have large photoionization cross-sections in the hard X-ray region. We use HAXPES for chemical analysis of trace elements in Pd nanoparticle catalysts immobilized on sulfur-terminated substrates and Pt{sub 3}Ni nanoparticle catalysts enveloped by dendrimer molecules.

  13. Providing x-rays

    International Nuclear Information System (INIS)

    Mallozzi, P.J.; Epstein, H.M.

    1985-01-01

    This invention provides an apparatus for providing x-rays to an object that may be in an ordinary environment such as air at approximately atmospheric pressure. The apparatus comprises: means (typically a laser beam) for directing energy onto a target to produce x-rays of a selected spectrum and intensity at the target; a fluid-tight enclosure around the target; means for maintaining the pressure in the first enclosure substantially below atmospheric pressure; a fluid-tight second enclosure adjoining the first enclosure, the common wall portion having an opening large enough to permit x-rays to pass through but small enough to allow the pressure reducing means to evacuate gas from the first enclosure at least as fast as it enters through the opening; the second enclosure filled with a gas that is highly transparent to x-rays; the wall of the second enclosure to which the x-rays travel having a portion that is highly transparent to x-rays (usually a beryllium or plastic foil), so that the object to which the x-rays are to be provided may be located outside the second enclosure and adjacent thereto and thus receive the x-rays substantially unimpeded by air or other intervening matter. The apparatus is particularly suited to obtaining EXAFS (extended x-ray fine structure spectroscopy) data on a material

  14. A new method for information retrieval in two-dimensional grating-based X-ray phase contrast imaging

    International Nuclear Information System (INIS)

    Wang Zhi-Li; Gao Kun; Chen Jian; Ge Xin; Tian Yang-Chao; Wu Zi-Yu; Zhu Pei-Ping

    2012-01-01

    Grating-based X-ray phase contrast imaging has been demonstrated to be an extremely powerful phase-sensitive imaging technique. By using two-dimensional (2D) gratings, the observable contrast is extended to two refraction directions. Recently, we have developed a novel reverse-projection (RP) method, which is capable of retrieving the object information efficiently with one-dimensional (1D) grating-based phase contrast imaging. In this contribution, we present its extension to the 2D grating-based X-ray phase contrast imaging, named the two-dimensional reverse-projection (2D-RP) method, for information retrieval. The method takes into account the nonlinear contributions of two refraction directions and allows the retrieval of the absorption, the horizontal and the vertical refraction images. The obtained information can be used for the reconstruction of the three-dimensional phase gradient field, and for an improved phase map retrieval and reconstruction. Numerical experiments are carried out, and the results confirm the validity of the 2D-RP method

  15. Rapid simulation of X-ray transmission imaging for baggage inspection via GPU-based ray-tracing

    Science.gov (United States)

    Gong, Qian; Stoian, Razvan-Ionut; Coccarelli, David S.; Greenberg, Joel A.; Vera, Esteban; Gehm, Michael E.

    2018-01-01

    We present a pipeline that rapidly simulates X-ray transmission imaging for arbitrary system architectures using GPU-based ray-tracing techniques. The purpose of the pipeline is to enable statistical analysis of threat detection in the context of airline baggage inspection. As a faster alternative to Monte Carlo methods, we adopt a deterministic approach for simulating photoelectric absorption-based imaging. The highly-optimized NVIDIA OptiX API is used to implement ray-tracing, greatly speeding code execution. In addition, we implement the first hierarchical representation structure to determine the interaction path length of rays traversing heterogeneous media described by layered polygons. The accuracy of the pipeline has been validated by comparing simulated data with experimental data collected using a heterogenous phantom and a laboratory X-ray imaging system. On a single computer, our approach allows us to generate over 400 2D transmission projections (125 × 125 pixels per frame) per hour for a bag packed with hundreds of everyday objects. By implementing our approach on cloud-based GPU computing platforms, we find that the same 2D projections of approximately 3.9 million bags can be obtained in a single day using 400 GPU instances, at a cost of only 0.001 per bag.

  16. Design and validation of inert homemade explosive simulants for X-ray-based inspection systems

    Science.gov (United States)

    Faust, Anthony A.; Nacson, Sabatino; Koffler, Bruce; Bourbeau, Éric; Gagne, Louis; Laing, Robin; Anderson, C. J.

    2014-05-01

    Transport Canada (TC), the Canadian Armed Forces, and other public security agencies have an interest in the assessment of the potential utility of advanced explosives detection technologies to aid in the detection and interdiction of commercial grade, military grade, and homemade or improvised explosives (HME or IE). The availability of suitable, non-hazardous, non-toxic, explosive simulants is of concern when assessing the potential utility of such detection systems. Lack of simulants limits the training opportunities, and ultimately the detection probability, of security personnel using these systems. While simulants for commercial and military grade explosives are available for a wide variety of detection technologies, the design and production of materials to simulate improvised explosives has not kept pace with this emerging threat. Funded by TC and the Canadian Safety and Security Program, Defence Research and Development Canada (DRDC), Visiontec Systems, and Optosecurity engaged in an effort to develop inert, non-toxic Xray interrogation simulants for IE materials such as ammonium nitrate, potassium chlorate, and triacetone triperoxide. These simulants were designed to mimic key X-ray interrogation-relevant material properties of real improvised explosives, principally their bulk density and effective atomic number. Different forms of the simulants were produced and tested, simulating the different explosive threat formulations that could be encountered by front line security workers. These simulants comply with safety and stability requirements, and as best as possible match form and homogeneity. This paper outlines the research program, simulant design, and validation.

  17. Edgeless silicon sensors for Medipix-based large-area X-ray imaging detectors

    International Nuclear Information System (INIS)

    Bosma, M J; Visser, J; Koffeman, E N; Evrard, O; De Moor, P; De Munck, K; Tezcan, D Sabuncuoglu

    2011-01-01

    Some X-ray imaging applications demand sensitive areas exceeding the active area of a single sensor. This requires a seamless tessellation of multiple detector modules with edgeless sensors. Our research is aimed at minimising the insensitive periphery that isolates the active area from the edge. Reduction of the edge-defect induced charge injection, caused by the deleterious effects of dicing, is an important step. We report on the electrical characterisation of 300 μm thick edgeless silicon p + -ν-n + diodes, diced using deep reactive ion etching. Sensors with both n-type and p-type stop rings were fabricated in various edge topologies. Leakage currents in the active area are compared with those of sensors with a conventional design. As expected, we observe an inverse correlation between leakage-current density and both the edge distance and stop-ring width. From this correlation we determine a minimum acceptable edge distance of 50 μm. We also conclude that structures with a p-type stop ring show lower leakage currents and higher breakdown voltages than the ones with an n-type stop ring.

  18. Traceable size determination of PMMA nanoparticles based on Small Angle X-ray Scattering (SAXS)

    Energy Technology Data Exchange (ETDEWEB)

    Gleber, G; Cibik, L; Mueller, P; Krumrey, M [Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin (Germany); Haas, S; Hoell, A, E-mail: gudrun.gleber@ptb.d [Helmholtz-Zentrum-Berlin fuer Materialien und Energie (HZB), Albert-Einstein-Strasse 15, 12489 Berlin (Germany)

    2010-10-01

    The size and size distribution of PMMA nanoparticles has been investigated with SAXS (small angle X-ray scattering) using monochromatized synchrotron radiation. The uncertainty has contributions from the wavelength or photon energy of the radiation, the scattering angle and the fit procedure for the obtained scattering curves. The wavelength can be traced back to the lattice constant of silicon, and the scattering angle is traceable via geometric measurements of the detector pixel size and the distance between the sample and the detector. SAXS measurements and data evaluations have been performed at different distances and photon energies for two PMMA nanoparticle suspensions with low polydispersity and nominal diameters of 108 nm and 192 nm, respectively, as well as for a mixture of both. The relative variation of the diameters obtained for different experimental conditions was below {+-} 0.3 %. The determined number-weighted mean diameters of (109.0 {+-} 0.7) nm and (188.0 {+-} 1.3) nm, respectively, are close to the nominal values.

  19. Traceable size determination of PMMA nanoparticles based on Small Angle X-ray Scattering (SAXS)

    Science.gov (United States)

    Gleber, G.; Cibik, L.; Haas, S.; Hoell, A.; Müller, P.; Krumrey, M.

    2010-10-01

    The size and size distribution of PMMA nanoparticles has been investigated with SAXS (small angle X-ray scattering) using monochromatized synchrotron radiation. The uncertainty has contributions from the wavelength or photon energy of the radiation, the scattering angle and the fit procedure for the obtained scattering curves. The wavelength can be traced back to the lattice constant of silicon, and the scattering angle is traceable via geometric measurements of the detector pixel size and the distance between the sample and the detector. SAXS measurements and data evaluations have been performed at different distances and photon energies for two PMMA nanoparticle suspensions with low polydispersity and nominal diameters of 108 nm and 192 nm, respectively, as well as for a mixture of both. The relative variation of the diameters obtained for different experimental conditions was below ± 0.3 %. The determined number-weighted mean diameters of (109.0 ± 0.7) nm and (188.0 ± 1.3) nm, respectively, are close to the nominal values.

  20. Traceable size determination of PMMA nanoparticles based on Small Angle X-ray Scattering (SAXS)

    International Nuclear Information System (INIS)

    Gleber, G; Cibik, L; Mueller, P; Krumrey, M; Haas, S; Hoell, A

    2010-01-01

    The size and size distribution of PMMA nanoparticles has been investigated with SAXS (small angle X-ray scattering) using monochromatized synchrotron radiation. The uncertainty has contributions from the wavelength or photon energy of the radiation, the scattering angle and the fit procedure for the obtained scattering curves. The wavelength can be traced back to the lattice constant of silicon, and the scattering angle is traceable via geometric measurements of the detector pixel size and the distance between the sample and the detector. SAXS measurements and data evaluations have been performed at different distances and photon energies for two PMMA nanoparticle suspensions with low polydispersity and nominal diameters of 108 nm and 192 nm, respectively, as well as for a mixture of both. The relative variation of the diameters obtained for different experimental conditions was below ± 0.3 %. The determined number-weighted mean diameters of (109.0 ± 0.7) nm and (188.0 ± 1.3) nm, respectively, are close to the nominal values.

  1. Ross filter pairs for metal artefact reduction in x-ray tomography: a case study based on imaging and segmentation of metallic implants

    Science.gov (United States)

    Arhatari, Benedicta D.; Abbey, Brian

    2018-01-01

    Ross filter pairs have recently been demonstrated as a highly effective means of producing quasi-monoenergetic beams from polychromatic X-ray sources. They have found applications in both X-ray spectroscopy and for elemental separation in X-ray computed tomography (XCT). Here we explore whether they could be applied to the problem of metal artefact reduction (MAR) for applications in medical imaging. Metal artefacts are a common problem in X-ray imaging of metal implants embedded in bone and soft tissue. A number of data post-processing approaches to MAR have been proposed in the literature, however these can be time-consuming and sometimes have limited efficacy. Here we describe and demonstrate an alternative approach based on beam conditioning using Ross filter pairs. This approach obviates the need for any complex post-processing of the data and enables MAR and segmentation from the surrounding tissue by exploiting the absorption edge contrast of the implant.

  2. User certification of hand-held x-ray tube based analytical fluorescent devices in a canadian context

    International Nuclear Information System (INIS)

    Maharaj, H.P.

    2005-01-01

    Safety education aims to reduce personal injury and improve well being. This health promotion principle is applied in the case of hand-held open beam x-ray tube based analytical x-ray devices. Such devices not only are light weight and portable, but also present high radiation exposure levels at the beam exit port and potentially can be used in a variety of industrial applications for determination of material composition. There is much potential for radiation risks to occur with resultant adverse effects if such devices are not used by trained individuals within controlled environments. A level of radiation safety knowledge and understanding of the device design, construction and performance characteristics appear warranted. To reduce radiation risks, user certification at a federal level was introduced in 2004 based on International Standards Organization 20807, since that standard comprises elements commensurate with risk reduction strategies. Within these contexts, a federally certified user is deemed to have acquired a level of safety knowledge and skills to facilitate safe use of the device. Certification, however, does not absolve the holder from obligations of compliance with applicable provincial, territorial or federal laws respecting device operation. The union of federal certification and applicable legislative mandated operational criteria reduces radiation risks overall. (author)

  3. Measurements and simulations analysing the noise behaviour of grating-based X-ray phase-contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Weber, T., E-mail: thomas.weber@physik.uni-erlangen.de [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Bartl, P.; Durst, J. [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Haas, W. [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); University of Erlangen-Nuremberg, Pattern Recognition Lab, Martensstr. 3, 91058 Erlangen (Germany); Michel, T.; Ritter, A.; Anton, G. [University of Erlangen-Nuremberg, ECAP - Erlangen Center for Astroparticle Physics, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany)

    2011-08-21

    In the last decades, phase-contrast imaging using a Talbot-Lau grating interferometer is possible even with a low-brilliance X-ray source. With the potential of increasing the soft-tissue contrast, this method is on its way into medical imaging. For this purpose, the knowledge of the underlying physics of this technique is necessary. With this paper, we would like to contribute to the understanding of grating-based phase-contrast imaging by presenting results on measurements and simulations regarding the noise behaviour of the differential phases. These measurements were done using a microfocus X-ray tube with a hybrid, photon-counting, semiconductor Medipix2 detector. The additional simulations were performed by our in-house developed phase-contrast simulation tool 'SPHINX', combining both wave and particle contributions of the simulated photons. The results obtained by both of these methods show the same behaviour. Increasing the number of photons leads to a linear decrease of the standard deviation of the phase. The number of used phase steps has no influence on the standard deviation, if the total number of photons is held constant. Furthermore, the probability density function (pdf) of the reconstructed differential phases was analysed. It turned out that the so-called von Mises distribution is the physically correct pdf, which was also confirmed by measurements. This information advances the understanding of grating-based phase-contrast imaging and can be used to improve image quality.

  4. Prediction of SEM–X-ray images’ data of cement-based materials using artificial neural network algorithm

    Directory of Open Access Journals (Sweden)

    Ashraf Ragab Mohamed

    2014-09-01

    Full Text Available Recent advances of computational capabilities have motivated the development of more sophisticated models to simulate cement-based hydration. However, the input parameters for such models, obtained from SEM–X-ray image analyses, are quite complicated and hinder their versatile application. This paper addresses the utilization of the artificial neural networks (ANNs to predict the SEM–X-ray images’ data of cement-based materials (surface area fraction and the cement phases’ correlation functions. ANNs have been used to correlate these data, already obtained for 21 types of cement, to basic cement data (cement compounds and fineness. Two approaches have been proposed; the ANN, and the ANN-regression method. Comparisons have shown that the ANN proves effectiveness in predicting the surface area fraction, while the ANN-regression is more computationally suitable for the correlation functions. Results have shown good agreement between the proposed techniques and the actual data with respect to hydration products, degree of hydration, and simulated images.

  5. Stature estimation based on vertebral morphometry by dual energy X-rays absorptiometry imaging in Italian females

    Directory of Open Access Journals (Sweden)

    Chantal Milani

    2017-02-01

    Full Text Available Anthropological profile in forensic context includes the assessment of parameters as ancestry, sex, age and stature of an individual by the analysis of skeletal remains. Stature can be estimated from decomposed and fully or partially skeletonized remains by means of anatomical or mathematical methods applied on the whole skeleton or single bones. Many authors calculated regression formulae for the living stature estimation by these methods, in particular based on a population similar to the remains recovered. Long bones are commonly used for stature estimation, but, when they are missing, methods involving different parts of the skeleton are needed. In this preliminary study we measured heights of the vertebral bodies in a female Caucasian Italian population, evaluated by images of morphometric X-ray absorptiometry based on dual-energy X-ray absorptiometry in living subjects investigated for routine diagnostic purposes. Thoracic and lumbar segments of the spine were measured and statistical analysis was performed, thus obtaining regression formulae for estimated living stature from thoraco-lumbar spine segments (T6-T12, L1-L4 and T6-L4. We propose this method for stature evaluation in physical or forensic anthropology when the spine is available and long bones are missing.

  6. High-resolution non-invasive 3D imaging of paint microstructure by synchrotron-based X-ray laminography

    International Nuclear Information System (INIS)

    Reischig, Peter; Helfen, Lukas; Wallert, Arie; Baumbach, Tilo; Dik, Joris

    2013-01-01

    The characterisation of the microstructure and micromechanical behaviour of paint is key to a range of problems related to the conservation or technical art history of paintings. Synchrotron-based X-ray laminography is demonstrated in this paper to image the local sub-surface microstructure in paintings in a non-invasive and non-destructive way. Based on absorption and phase contrast, the method can provide high-resolution 3D maps of the paint stratigraphy, including the substrate, and visualise small features, such as pigment particles, voids, cracks, wood cells, canvas fibres etc. Reconstructions may be indicative of local density or chemical composition due to increased attenuation of X-rays by elements of higher atomic number. The paint layers and their interfaces can be distinguished via variations in morphology or composition. Results of feasibility tests on a painting mockup (oak panel, chalk ground, vermilion and lead white paint) are shown, where lateral and depth resolution of up to a few micrometres is demonstrated. The method is well adapted to study the temporal evolution of the stratigraphy in test specimens and offers an alternative to destructive sampling of original works of art. (orig.)

  7. Nitrogen incorporated ultrananocrystalline diamond based field emitter array for a flat-panel x-ray source

    International Nuclear Information System (INIS)

    Posada, Chrystian M.; Grant, Edwin J.; Lee, Hyoung K.; Castaño, Carlos H.; Divan, Ralu; Sumant, Anirudha V.; Rosenmann, Daniel; Stan, Liliana

    2014-01-01

    A field emission based flat-panel transmission x-ray source is being developed as an alternative for medical and industrial imaging. A field emitter array (FEA) prototype based on nitrogen incorporated ultrananocrystalline diamond film has been fabricated to be used as the electron source of this flat panel x-ray source. The FEA prototype was developed using conventional microfabrication techniques. The field emission characteristics of the FEA prototype were evaluated. Results indicated that emission current densities of the order of 6 mA/cm 2 could be obtained at electric fields as low as 10 V/μm to 20 V/μm. During the prototype microfabrication process, issues such as delamination of the extraction gate and poor etching of the SiO 2 insulating layer located between the emitters and the extraction layer were encountered. Consequently, alternative FEA designs were investigated. Experimental and simulation data from the first FEA prototype were compared and the results were used to evaluate the performance of alternative single and double gate designs that would yield better field emission characteristics compared to the first FEA prototype. The best simulation results are obtained for the double gate FEA design, when the diameter of the collimator gate is around 2.6 times the diameter of the extraction gate

  8. Performance of an X-ray spectroscopic system based on a double-gate double-feedback charge preamplifier

    CERN Document Server

    Fazzi, A

    2000-01-01

    The performance of a near room temperature X-ray spectroscopic system is reported. The system is based on a charge preamplifier with the first transistor having two separated gates. The preamplifier operates in a continuous reset mode without any physical resistor connected to the input node. The leakage current and the current due to the rate of X-rays is neutralized by an average current of holes, flowing under the control of an additional feedback, from the bottom to the top gate. The preamplifier is followed by a simple circuit which exactly cancels the long tail of the impulse response of a pure double-gate preamplifier. The compensation of this tail, due to the very principle of the preamplifier's continuous reset through the double-gate mechanism, improves substantially the high-rate performance of the system. The preamplifier based on a commercially available double-gate front JFET MX-40 (MOXTEK) coupled to a silicon drift detector produced at BNL achieved ENC of 13 electrons at -30 deg. C. The analys...

  9. Coherent x-rays and vacuum-ultraviolet radiation from storage-ring-based undulators and free electron lasers

    International Nuclear Information System (INIS)

    Kim, K.J.

    1984-12-01

    High-brightness electron storage rings and permanent-magnet technology provide a basis for the development of coherent radiation in the 10- to 1000-A (xuv) spectral range. The most assured route to the production of coherent x-rays and vuv is the simple interaction between properly constrained relativistic electrons and permanent-magnet undulators, a subject that is already well understood and where technology is well advanced. Other techniques are less well developed, but with increasing degrees of technical challenge they will provide additional coherence properties. Transverse optical klystrons (TOKs) provide an opportunity for additional coherence at certain harmonics of longer-wavelength lasers. Free electron lasers (FELs) extend coherence capabilities substantially through two possible routes: one is the development of suitable mirror coatings. Both FEL techniques would provide vuv radiation and soft x rays with extremely narrow spectral content. Research on all of these techniques (undulators, TOKs, and FELs) is possible in a single facility based on a high-brightness electron storage ring, referred to herein as a Coherent xuv Facility (CXF). Individual items from the report were prepared separately for the data base

  10. Wide field x-ray telescopes: Detecting x-ray transients/afterglows related to GRBs

    International Nuclear Information System (INIS)

    Hudec, Rene; Pina, Ladislav; Inneman, Adolf; Gorenstein, Paul

    1998-01-01

    The recent discovery of X-ray afterglows of GRBs opens the possibility of analyses of GRBs by their X-ray detections. However, imaging X-ray telescopes in current use mostly have limited fields of view. Alternative X-ray optics geometries achieving very large fields of view have been theoretically suggested in the 70's but not constructed and used so far. We review the geometries and basic properties of the wide-field X-ray optical systems based on one- and two-dimensional lobster-eye geometry and suggest technologies for their development and construction. First results of the development of double replicated X-ray reflecting flats for use in one-dimensional X-ray optics of lobster-eye type are presented and discussed. The optimum strategy for locating GRBs upon their X-ray counterparts is also presented and discussed

  11. Imaging X-ray astronomy

    International Nuclear Information System (INIS)

    Elvis, M.

    1990-01-01

    The launch of the High Energy Astrophysical Observatory, more appealingly called the Einstein Observatory, marked one of the most revolutionary steps taken in astrophysics this century. Its greater sensitivity compared with earlier satellites and its ability to make high spacial and spectral resolution observations transformed X-ray astronomy. This book is based on a Symposium held in Cambridge, Massachusetts, to celebrate a decade of Einstein Observatory's achievements. It discusses the contributions that this satellite has made to each area of modern astrophysics and the diversity of the ongoing work based on Einstein data. There is a guide to each of the main data bases now coming on-line to increase the availability and to preserve this valuable archive for the future. A review of NASA's next big X-ray mission, AXAF, and a visionary program for novel X-ray astronomy satellites by Riccardo Giacconi conclude this wide-ranging volume. (author)

  12. Novel Schiff Bases Based on the Quinolinone Skeleton: Syntheses, X-ray Structures and Fluorescent Properties

    Directory of Open Access Journals (Sweden)

    Zdeněk Trávníček

    2014-09-01

    Full Text Available A series of a new type of Schiff bases 1–7, derived from 2-phenyl-3-amino-4(1H-quinolinone and R-salicyladehyde derivatives wherein R = 3-hydroxy (1, 3,4-dihydroxy (2, 3-methoxy (3, 3-carboxy (4, 3-allyl (5, 5-chloro (6, and 5-nitro (7, was synthesized and structurally characterized. Each of the molecules 1, 3 and 7 consists of three planar moieties (i.e., a quinolinone and two phenyl rings, which are mutually oriented differently depending on the appropriate substituent R and the extent of non-covalent contacts stabilizing the crystal structures. The compounds were studied for their fluorescence properties, where compound 6 yielded the strongest intensity both in the solid phase and in 100 μM ethanol solution with a quantum yield of φ = 3.6% as compared to quinine sulfate used as a standard. The in vitro cytotoxicity of these compounds was tested against the human osteosarcoma (HOS and breast adenocarcinoma (MCF7 cell lines, revealing no activity up to the concentration of 50 µM.

  13. X-ray interferometers

    International Nuclear Information System (INIS)

    Franks, A.

    1980-01-01

    An improved type of amplitude-division x-ray interferometer is described. The wavelength at which the interferometer can operate is variable, allowing the instrument to be used to measure x-ray wavelength, and the angle of inclination is variable for sample investigation. (U.K.)

  14. Extremity x-ray

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003461.htm Extremity x-ray To use the sharing features on this page, ... in the body Risks There is low-level radiation exposure. X-rays are monitored and regulated to provide the ...

  15. X-rays utilization

    International Nuclear Information System (INIS)

    Rebigan, F.

    1979-03-01

    The modality of X-ray utilization in different activities and economy is given. One presents firstly quantities and units used in radiation dosimetry and other fields. One gives the generation of X-rays, their properties as well as the elements of radiation protection. The utilization characteristics of these radiations in different fields are finally given. (author)

  16. Chest X-Ray

    Medline Plus

    Full Text Available ... by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, ... d like to talk with you about chest radiography also known as chest x-rays. Chest x- ...

  17. Superconducting single X-ray photon detector based on W0.8Si0.2

    Directory of Open Access Journals (Sweden)

    Xiaofu Zhang

    2016-11-01

    Full Text Available We fabricated a superconducting single X-ray photon detector based on W0.8Si0.2, and we characterized its basic detection performance for keV-photons at different temperatures. The detector has a critical temperature of 4.97 K, and it is able to be operated up to 4.8 K, just below the critical temperature. The detector starts to react to X-ray photons at relatively low bias currents, less than 1% of Ic at T = 1.8 K, and it shows a saturated count rate dependence on bias current at all temperatures, indicating that the optimum internal quantum efficiency can always be reached. Dark counts are negligible up to the highest investigated bias currents (99% of Ic and operating temperature (4.8 K. The latching effect affects the detector performance at all temperatures due to the fast recovery of the bias current; however, further modifications of the device geometry are expected to reduce the tendency for latching.

  18. A Control System and Streaming DAQ Platform with Image-Based Trigger for X-ray Imaging

    Science.gov (United States)

    Stevanovic, Uros; Caselle, Michele; Cecilia, Angelica; Chilingaryan, Suren; Farago, Tomas; Gasilov, Sergey; Herth, Armin; Kopmann, Andreas; Vogelgesang, Matthias; Balzer, Matthias; Baumbach, Tilo; Weber, Marc

    2015-06-01

    High-speed X-ray imaging applications play a crucial role for non-destructive investigations of the dynamics in material science and biology. On-line data analysis is necessary for quality assurance and data-driven feedback, leading to a more efficient use of a beam time and increased data quality. In this article we present a smart camera platform with embedded Field Programmable Gate Array (FPGA) processing that is able to stream and process data continuously in real-time. The setup consists of a Complementary Metal-Oxide-Semiconductor (CMOS) sensor, an FPGA readout card, and a readout computer. It is seamlessly integrated in a new custom experiment control system called Concert that provides a more efficient way of operating a beamline by integrating device control, experiment process control, and data analysis. The potential of the embedded processing is demonstrated by implementing an image-based trigger. It records the temporal evolution of physical events with increased speed while maintaining the full field of view. The complete data acquisition system, with Concert and the smart camera platform was successfully integrated and used for fast X-ray imaging experiments at KIT's synchrotron radiation facility ANKA.

  19. Morphometric X-ray Absorptiometry: Reference Data for Vertebral Dimensions in a Population-based Sample of Young Danish Men

    International Nuclear Information System (INIS)

    Wulff, R.; Koch Holst, A.; Nielsen, T.L.; Andersen, M.; Hagen, C.; Brixen, K.

    2004-01-01

    Purpose: To determine reference values for vertebral heights in healthy young Danish males using morphometric X-ray absorptiometry (MXA). Material and Methods: A population-based study group of 487 males aged between 20 and 30 years (mean 25 years) from the county of Funen, Denmark, were recruited. Using a Hologic QDR 4500 (dual energy X-ray absorptiometry) DXA-scanner, MXA scans covering the vertebrae from T4 to L4 were acquired for each subject. Anterior (Ha), middle (Hm), and posterior (Hp) heights of the thoracic (T4-T12) and lumbar (L1-L4) vertebral bodies were measured. Moreover, wedge, mid-wedge, crush I, and crush II ratios were calculated. Results: No correlation between vertebral dimensions and crush indices on the one hand and age or weight on the other were found. Body height, however, correlated significantly with the cumulated vertebral heights. Reference data for vertebral dimensions, wedge, mid-wedge, crush I, and crush II are tabulated. Conclusion: The anterior, middle, and posterior heights of the vertebral bodies of T4 to L4 can be measured reproducible with MXA. In young men, the cumulative vertebral heights correlated with body height but not with age. Moreover, the wedge and crush indices were unrelated of both age and height

  20. Using high resolution X-ray computed tomography to create an image based model of a lymph node.

    Science.gov (United States)

    Cooper, L J; Zeller-Plumhoff, B; Clough, G F; Ganapathisubramani, B; Roose, T

    2018-07-14

    Lymph nodes are an important part of the immune system. They filter the lymphatic fluid as it is transported from the tissues before being returned to the blood stream. The fluid flow through the nodes influences the behaviour of the immune cells that gather within the nodes and the structure of the node itself. Measuring the fluid flow in lymph nodes experimentally is challenging due to their small size and fragility. In this paper, we present high resolution X-ray computed tomography images of a murine lymph node. The impact of the resulting visualized structures on fluid transport are investigated using an image based model. The high contrast between different structures within the lymph node provided by phase contrast X-ray computed tomography reconstruction results in images that, when related to the permeability of the lymph node tissue, suggest an increased fluid velocity through the interstitial channels in the lymph node tissue. Fluid taking a direct path from the afferent to the efferent lymphatic vessel, through the centre of the node, moved faster than the fluid that flowed around the periphery of the lymph node. This is a possible mechanism for particles being moved into the cortex. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Pixel readout ASIC for an APD based 2D X-ray hybrid pixel detector with sub-nanosecond resolution

    Energy Technology Data Exchange (ETDEWEB)

    Thil, Ch., E-mail: christophe.thil@ziti.uni-heidelberg.d [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Baron, A.Q.R. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Fajardo, P. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France); Fischer, P. [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Graafsma, H. [DESY, Notkestrasse 85, 22607 Hamburg (Germany); Rueffer, R. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France)

    2011-02-01

    The fast response and the short recovery time of avalanche photodiodes (APDs) in linear mode make those devices ideal for direct X-ray detection in applications requiring high time resolution or counting rate. In order to provide position sensitivity, the XNAP project aims at creating a hybrid pixel detector with nanosecond time resolution based on a monolithic APD sensor array with 32 x32 pixels covering about 1 cm{sup 2} active area. The readout is implemented in a pixelated front-end ASIC suited for the readout of such arrays, matched to pixels of 280{mu}mx280{mu}m size. Every single channel features a fast transimpedance amplifier, a discriminator with locally adjustable threshold and two counters with high dynamic range and counting speed able to accumulate X-ray hits with no readout dead time. Additionally, the detector can be operated in list mode by time-stamping every single event with sub-nanosecond resolution. In a first phase of the project, a 4x4 pixel test module is built to validate the conceptual design of the detector. The XNAP project is briefly presented and the performance of the readout ASIC is discussed.

  2. Pixel readout ASIC for an APD based 2D X-ray hybrid pixel detector with sub-nanosecond resolution

    International Nuclear Information System (INIS)

    Thil, Ch.; Baron, A.Q.R.; Fajardo, P.; Fischer, P.; Graafsma, H.; Rueffer, R.

    2011-01-01

    The fast response and the short recovery time of avalanche photodiodes (APDs) in linear mode make those devices ideal for direct X-ray detection in applications requiring high time resolution or counting rate. In order to provide position sensitivity, the XNAP project aims at creating a hybrid pixel detector with nanosecond time resolution based on a monolithic APD sensor array with 32 x32 pixels covering about 1 cm 2 active area. The readout is implemented in a pixelated front-end ASIC suited for the readout of such arrays, matched to pixels of 280μmx280μm size. Every single channel features a fast transimpedance amplifier, a discriminator with locally adjustable threshold and two counters with high dynamic range and counting speed able to accumulate X-ray hits with no readout dead time. Additionally, the detector can be operated in list mode by time-stamping every single event with sub-nanosecond resolution. In a first phase of the project, a 4x4 pixel test module is built to validate the conceptual design of the detector. The XNAP project is briefly presented and the performance of the readout ASIC is discussed.

  3. Study of Cr(VI) adsorption onto magnetite nanoparticles using synchrotron-based X-ray absorption spectroscopy

    Science.gov (United States)

    Chen, Yen-Hua; Liu, Dian-Yu; Lee, Jyh-Fu

    2018-04-01

    In this study, the efficiency of Cr(VI) adsorption onto nano-magnetite was examined by batch experiments, and the Cr(VI) adsorption mechanism was investigated using synchrotron-based X-ray absorption spectroscopy. Magnetite nanoparticles with a mean diameter of 10 nm were synthesized using an inexpensive and simple co-precipitation method. It shows a saturation magnetization of 54.3 emu/g, which can be recovered with an external magnetic field. The adsorption data fitted the Langmuir adsorption isotherm well, implying a monolayer adsorption behavior of Cr(VI) onto nano-magnetite. X-ray absorption spectroscopy results indicate that the adsorption mechanism involves electron transfer between Fe(II) in nano-magnetite (Fe2+OFe3+ 2O3) and Cr(VI) to transform into Cr(III), which may exist as an Fe(III)-Cr(III) mixed solid phase. Moreover, the Cr(III)/Cr(VI) ratio in the final products can be determined by the characteristic pre-edge peak area of Cr(VI) in the Cr K-edge spectrum. These findings suggest that nano-magnetite is effective for Cr(VI) removal from wastewater because it can transform highly poisonous Cr(VI) species into nontoxic Cr(III) compounds, which are highly insoluble and immobile under environmental conditions.

  4. Myoanatomy of the velvet worm leg revealed by laboratory-based nanofocus X-ray source tomography.

    Science.gov (United States)

    Müller, Mark; de Sena Oliveira, Ivo; Allner, Sebastian; Ferstl, Simone; Bidola, Pidassa; Mechlem, Korbinian; Fehringer, Andreas; Hehn, Lorenz; Dierolf, Martin; Achterhold, Klaus; Gleich, Bernhard; Hammel, Jörg U; Jahn, Henry; Mayer, Georg; Pfeiffer, Franz

    2017-11-21

    X-ray computed tomography (CT) is a powerful noninvasive technique for investigating the inner structure of objects and organisms. However, the resolution of laboratory CT systems is typically limited to the micrometer range. In this paper, we present a table-top nanoCT system in conjunction with standard processing tools that is able to routinely reach resolutions down to 100 nm without using X-ray optics. We demonstrate its potential for biological investigations by imaging a walking appendage of Euperipatoides rowelli , a representative of Onychophora-an invertebrate group pivotal for understanding animal evolution. Comparative analyses proved that the nanoCT can depict the external morphology of the limb with an image quality similar to scanning electron microscopy, while simultaneously visualizing internal muscular structures at higher resolutions than confocal laser scanning microscopy. The obtained nanoCT data revealed hitherto unknown aspects of the onychophoran limb musculature, enabling the 3D reconstruction of individual muscle fibers, which was previously impossible using any laboratory-based imaging technique.

  5. In situ synchrotron x-ray characterization of microstructure formation in solidification processing of Al-based metallic alloys

    International Nuclear Information System (INIS)

    Billia, Bernard; Nguyen-Thi, Henri; Mangelinck-Noel, Nathalie

    2010-01-01

    The microstructure formed during the solidification step has a major influence on the properties of materials processed by major techniques (casting, welding ...). In situ and real-time characterization by synchrotron X-ray imaging is the method of choice to unveil the dynamical formation of the solidification microstructure in metallic alloys, and thus provide precise data for the critical validation of the theoretical predictions that is needed for sound advancement of modeling and numerical simulation. After a description of the experimental procedure used at the European Synchrotron Radiation Facility (ESRF), dynamical phenomena in the formation of the grain structure and dendritic or equiaxed solidification microstructure in Al-based alloys are presented. Beyond fluid flow interaction, earth gravity induces stresses, deformation and fragmentation in the dendritic mush. Settling of dendrite arms and equiaxed grains thus occurs, in particular in the columnar to equiaxed transition. Other types of stresses and strains are caused by the mere formation of the solidification microstructure itself. In white-beam X-ray topography, stresses and strains are manifested by specific contrasts and breaking of the Laue images into several pieces. Finally, quantitative analysis of the grey level in radiographs enables the analysis of solute segregation, which noticeably results in solutal poisoning of growth when equiaxed grains are interacting. (author)

  6. Calibration data Analysis Package (CAP): An IDL based widget application for analysis of X-ray calibration data

    Science.gov (United States)

    Vaishali, S.; Narendranath, S.; Sreekumar, P.

    An IDL (interactive data language) based widget application developed for the calibration of C1XS (Narendranath et al., 2010) instrument on Chandrayaan-1 is modified to provide a generic package for the analysis of data from x-ray detectors. The package supports files in ascii as well as FITS format. Data can be fitted with a list of inbuilt functions to derive the spectral redistribution function (SRF). We have incorporated functions such as `HYPERMET' (Philips & Marlow 1976) including non Gaussian components in the SRF such as low energy tail, low energy shelf and escape peak. In addition users can incorporate additional models which may be required to model detector specific features. Spectral fits use a routine `mpfit' which uses Leven-Marquardt least squares fitting method. The SRF derived from this tool can be fed into an accompanying program to generate a redistribution matrix file (RMF) compatible with the X-ray spectral analysis package XSPEC. The tool provides a user friendly interface of help to beginners and also provides transparency and advanced features for experts.

  7. Analysis of the Relationship Between the Solar X-Ray Radiation Intensity and the D-Region Electron Density Using Satellite and Ground-Based Radio Data

    Science.gov (United States)

    Nina, Aleksandra; Čadež, Vladimir M.; Bajčetić, Jovan; Mitrović, Srdjan T.; Popović, Luka Č.

    2018-04-01

    Increases in the X-ray radiation that is emitted during a solar X-ray flare induce significant changes in the ionospheric D region. Because of the numerous complex processes in the ionosphere and the characteristics of the radiation and plasma, the causal-consequential relationship between the X-ray radiation and ionospheric parameters is not easily determined. In addition, modeling the ionospheric D-region plasma parameters is very difficult because of the lack of data for numerous time- and space-dependent physical quantities. In this article we first give a qualitative analysis of the relationship between the electron density and the recorded solar X-ray intensity. After this, we analyze the differences in the relationships between the D-region response and various X-ray radiation properties. The quantitative study is performed for data observed on 5 May 2010 in the time period between 11:40 UT - 12:40 UT when the GOES 14 satellite detected a considerable X-ray intensity increase. Modeling the electron density is based on characteristics of the 23.4 kHz signal emitted in Germany and recorded by the receiver in Serbia.

  8. The MEL-X project at the Lawrence Livermore National Laboratory: a mirror-based delay line for x-rays

    Science.gov (United States)

    Pardini, Tom; Hill, Randy; Decker, Todd; Alameda, Jennifer; Soufli, Regina; Aquila, Andy; Guillet, Serge; Boutet, Sébastien; Hau-Riege, Stefan P.

    2015-09-01

    At the Lawrence Livermore National Laboratory (LLNL) in collaboration with the Linac Coherent Light Source (LCLS) we are developing a mirror-based delay line for x-rays (MEL-X) to enable x-ray pump/x-ray probe experiments at Free Electron Lasers (XFELs). The goal of this project is the development and deployment of a proof-of-principle delay line featuring coated x-ray optics. The four-mirror design of the MEL-X is motivated by the need for ease of alignment and use. In order to simplify the overlap of the pump and the probe beam after each delay time change, a scheme involving super-polished rails and mirror-to-motor decoupling has been adopted. The MEL-X, used in combination with a bright pulsed source like LCLS, features a capability for a high intensity pump beam. Its Iridium coating allows it to work at hard x-ray energies all the way up to 9 keV, with a probe beam transmission of 35% up to 8keV, and 14% at 9keV. The delay time can be tailored to each particular experiment, with a nominal range of 70 - 350 fs for this prototype. The MEL-X, combined with established techniques such as x-ray diffraction, absorption or emission, could provide new insights on ultra-fast transitions in highly excited states of matter.

  9. Methodological challenges of optical tweezers-based X-ray fluorescence imaging of biological model organisms at synchrotron facilities.

    Science.gov (United States)

    Vergucht, Eva; Brans, Toon; Beunis, Filip; Garrevoet, Jan; Bauters, Stephen; De Rijcke, Maarten; Deruytter, David; Janssen, Colin; Riekel, Christian; Burghammer, Manfred; Vincze, Laszlo

    2015-07-01

    Recently, a radically new synchrotron radiation-based elemental imaging approach for the analysis of biological model organisms and single cells in their natural in vivo state was introduced. The methodology combines optical tweezers (OT) technology for non-contact laser-based sample manipulation with synchrotron radiation confocal X-ray fluorescence (XRF) microimaging for the first time at ESRF-ID13. The optical manipulation possibilities and limitations of biological model organisms, the OT setup developments for XRF imaging and the confocal XRF-related challenges are reported. In general, the applicability of the OT-based setup is extended with the aim of introducing the OT XRF methodology in all research fields where highly sensitive in vivo multi-elemental analysis is of relevance at the (sub)micrometre spatial resolution level.

  10. Ultrasound and X-ray-based bone densitometry in patients with anorexia nervosa.

    Science.gov (United States)

    Resch, H; Newrkla, S; Grampp, S; Resch, A; Zapf, S; Piringer, S; Hockl, A; Weiss, P

    2000-05-01

    In 20 patients (mean age 23+/-5 years) with anorexia nervosa (AN), bone mass was evaluated by broadband ultrasound attenuation (BUA) of the calcaneus, peripheral quantitative computed tomography (pQCT) of the distal radius, and dual X-ray absorptiometry (DXA) of the lumbar spine and the hip. Compared with 20 age- and sex- matched healthy controls, patients with AN showed marked osteopenia at all measuring sites. Values of BUA (33.0+/-9 dB/MHz vs. 51.0+/-5.7 dB/MHz; P<0.0001) and of BMD of all regions of the hip (e.g., femoral neck: 0.71+/-0.13 g/cm(2) versus 0.89+/-0.07 g/cm(2); P<0.001), lumbar spine (0.82+/-0.15 g/cm(2) versus 1.24+/-0.06 g/cm(2); P<0.003) and total BMD of the peripheral radius (303.2+/-75 g/cm(3) versus 369.4+/-53.2 g/cm(3), P<0.001) were significantly reduced. Calculating a Z-score we found the most prominent differences between AN and controls by BUA of the calcaneus (-3.2+/-1.6), followed by DXA at the lumbar spine (-2.9+/-2.2) and the hip (femoral neck -2.1+/-1.7) and by pQCT at the distal radius (total BMD -1.2+/-2.0). There were highly significant correlations between BUA of the calcaneus and BMD of the femoral neck (r = 0.78, P<0.0001) and lumbar spine (r = 0.75, P<0.0001) as well as between BMD values of the femoral neck and lumbar spine (r = 0.95; P<0.0001). In addition, there were significant correlations (P<0.001) between body mass index (BMI) and the three different measuring sites and between the duration of the disease and BUA (r = 0.5, P<0.05). Our data suggest that BUA of the calcaneus is a valuable tool in the management of osteoporosis. Being a fast, radiation-free investigation method of good acceptance, it may be well suited for an assessment of the skeletal status in patients with AN.

  11. X-ray of osteopathies

    International Nuclear Information System (INIS)

    Freyschmidt, J.

    1980-01-01

    Osteoporosis, osteomalcia, fibro-osteoclasia and osteosclerosis are essential reactions to pathologicometabolic processes of the bone. The X-ray film shows precisely which changes have taken place in the bone structure, thus supplying the means for an analysis based on anatomic pathology. These phenomena are discussed in detail, special attention being paid to structural modifications. Attention is also focused on the problems connected with X-ray technology. The value of direct and indirect magnification of the skeleton of the hand for the identification and classification of esteopathies is explained. Phenomena observed in X-ray films, such as enosteal erosion, intracortical longitudinal stripes or tunnelisation, as well as subperiostal absorption, can be of pathognomonic importance for certain osteopathies. (orig.) [de

  12. Determination of liquid's molecular interference function based on X-ray diffraction and dual-energy CT in security screening

    International Nuclear Information System (INIS)

    Zhang, Li; YangDai, Tianyi

    2016-01-01

    A method for deriving the molecular interference function (MIF) of an unknown liquid for security screening is presented. Based on the effective atomic number reconstructed from dual-energy computed tomography (CT), equivalent molecular formula of the liquid is estimated. After a series of optimizations, the MIF and a new effective atomic number are finally obtained from the X-ray diffraction (XRD) profile. The proposed method generates more accurate results with less sensitivity to the noise and data deficiency of the XRD profile. - Highlights: • EDXRD combined with dual-energy CT has been utilized for deriving the molecular interference function of an unknown liquid. • The liquid's equivalent molecular formula is estimated based on the effective atomic number reconstructed from dual-energy CT. • The proposed method provides two ways to estimate the molecular interference function: the simplified way and accurate way. • A new effective atomic number of the liquid could be obtained.

  13. Structure of Profiled Crystals Based on Solid Solutions of Bi2Te3 and Their X-Ray Diagnostics

    Science.gov (United States)

    Voronin, A. I.; Bublik, V. T.; Tabachkova, N. Yu.; Belov, Yu. M.

    2011-05-01

    In this work, we used x-ray structural diagnostic data to reveal the formation of structural regularities in profiled polycrystalline ingots based on Bi and Sb chalcogenide solid solutions. In Bi2Te3 lattice crystals, the solid phase grows such that the cleavage surfaces are perpendicular to the crystallization front. The crystallization singularity determines the nature of the growth texture. Because texture is an important factor determining the anisotropy of properties, which in turn determines the suitability of an ingot for production of modules and the possibility of figure of merit improvement, its diagnostics is an important issue for technology testing. Examples of texture analysis using the method of straight pole figure (SPF) construction for profiled crystals are provided. The structure of the surface layers in the profiled ingots was studied after electroerosion cutting. In addition, the method of estimation of the disturbed layer depth based on the nature of texture changes was used.

  14. Boundary-enhancement in propagation-based x-ray phase-contrast tomosynthesis improves depth position characterization.

    Science.gov (United States)

    Guan, Huifeng; Xu, Qiaofeng; Garson, Alfred B; Anastasio, Mark A

    2015-04-21

    Propagation-based x-ray phase-contrast (PB XPC) tomosynthesis combines the concepts of tomosynthesis and XPC imaging to realize the advantages of both for biological imaging applications. Tomosynthesis permits reductions in acquisition times compared with full-view tomography, while XPC imaging provides the opportunity to resolve weakly absorbing structures. In this note, an investigation of the depth resolving properties of PB XPC tomosynthesis is conducted. The results demonstrate that in-plane structures display strong boundary-enhancement while out-of-plane structures do not. This effect can facilitate the identification of in-plane structures in PB XPC tomosynthesis that could normally not be distinguished from out-of-plane structures in absorption-based tomosynthesis.

  15. Boundary-enhancement in propagation-based x-ray phase-contrast tomosynthesis improves depth position characterization

    International Nuclear Information System (INIS)

    Guan, Huifeng; Xu, Qiaofeng; Garson, Alfred B III; Anastasio, Mark A

    2015-01-01

    Propagation-based x-ray phase-contrast (PB XPC) tomosynthesis combines the concepts of tomosynthesis and XPC imaging to realize the advantages of both for biological imaging applications. Tomosynthesis permits reductions in acquisition times compared with full-view tomography, while XPC imaging provides the opportunity to resolve weakly absorbing structures. In this note, an investigation of the depth resolving properties of PB XPC tomosynthesis is conducted. The results demonstrate that in-plane structures display strong boundary-enhancement while out-of-plane structures do not. This effect can facilitate the identification of in-plane structures in PB XPC tomosynthesis that could normally not be distinguished from out-of-plane structures in absorption-based tomosynthesis. (note)

  16. Cone Beam X-Ray Luminescence Tomography Imaging Based on KA-FEM Method for Small Animals.

    Science.gov (United States)

    Chen, Dongmei; Meng, Fanzhen; Zhao, Fengjun; Xu, Cao

    2016-01-01

    Cone beam X-ray luminescence tomography can realize fast X-ray luminescence tomography imaging with relatively low scanning time compared with narrow beam X-ray luminescence tomography. However, cone beam X-ray luminescence tomography suffers from an ill-posed reconstruction problem. First, the feasibility of experiments with different penetration and multispectra in small animal has been tested using nanophosphor material. Then, the hybrid reconstruction algorithm with KA-FEM method has been applied in cone beam X-ray luminescence tomography for small animals to overcome the ill-posed reconstruction problem, whose advantage and property have been demonstrated in fluorescence tomography imaging. The in vivo mouse experiment proved the feasibility of the proposed method.

  17. X-ray lasers

    CERN Document Server

    Elton, Raymond C

    2012-01-01

    The first in its field, this book is both an introduction to x-ray lasers and a how-to guide for specialists. It provides new entrants and others interested in the field with a comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. In one succinct volume, X-Ray Lasers collects the knowledge and experience gained in two decades of x-ray laser development and conveys the exciting challenges and possibilities still to come._Add on for longer version of blurb_M>The reader is first introduced

  18. X-ray apparatus

    International Nuclear Information System (INIS)

    Bernstein, S.; Stagg, L.; Lambert, T.W.; Griswa, P.J.

    1976-01-01

    A patient support system for X-ray equipment in arteriographic studies of the heart is described in detail. The support system has been designed to overcome many of the practical problems encountered in using previous types of arteriographic X-ray equipment. The support system is capable of horizontal movement and, by a series of shafts attached to the main support system, the X-ray source and image intensifier or detector may be rotated through the same angle. The system is highly flexible and details are given of several possible operational modes. (U.K.)

  19. X-ray detector

    International Nuclear Information System (INIS)

    Whetten, N.R.; Houston, J.M.

    1977-01-01

    An ionization chamber for use in determining the spatial distribution of x-ray photons in tomography systems comprises a plurality of substantially parallel, planar anodes separated by parallel, planar cathodes and enclosed in a gas of high atomic weight at a pressure from approximately 10 atmospheres to approximately 50 atmospheres. The cathode and anode structures comprise metals which are substantially opaque to x-ray radiation and thereby tend to reduce the resolution limiting effects of x-ray fluoresence in the gas. In another embodiment of the invention the anodes comprise parallel conductive bars disposed between two planar cathodes. Guard rings eliminate surface leakage currents between adjacent electrodes. 8 figures

  20. X-ray apparatus

    International Nuclear Information System (INIS)

    Grady, J.K.

    1985-01-01

    X-ray apparatus is described which has a shutter between the X-ray source and the patient. The shutter controls the level of radiation to which the patient is exposed instead of merely discontinuing the electric power supplied to the source. When the shutter is opened a radiation sensor senses the level of X-radiation. When a preset quantity of X-radiation has been measured an exposure control closes the shutter. Instead of using the radiation sensor, the integrated power supplied to the anode of the X-ray source may be measured. (author)

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive medical ...

  2. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small dose ... limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is ...

  3. X-ray examination apparatus

    NARCIS (Netherlands)

    2000-01-01

    The invention relates to an X-ray apparatus which includes an adjustable X-ray filter. In order to adjust an intensity profile of the X-ray beam, an X-ray absorbing liquid is transported to filter elements of the X-ray filter. Such transport is susceptible to gravitational forces which lead to an

  4. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

  5. Bone X-Ray (Radiography)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

  7. Abdomen X-Ray (Radiography)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Abdomen Abdominal x-ray uses a very small ... of an abdominal x-ray? What is abdominal x-ray? An x-ray (radiograph) is a noninvasive medical ...

  8. Development of a laser-based heating system for in situ synchrotron-based X-ray tomographic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fife, Julie L., E-mail: julie.fife@psi.ch [Laboratory for Synchrotron Radiation, Swiss Light Source, Paul Scherrer Institut, Villigen (Switzerland); Computational Materials Laboratory, Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland); Rappaz, Michel [Computational Materials Laboratory, Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland); Pistone, Mattia [Institute for Geochemistry and Petrology, Swiss Federal Institute of Technology of Zurich, Zurich (Switzerland); Celcer, Tine [Laboratory for Synchrotron Radiation, Swiss Light Source, Paul Scherrer Institut, Villigen (Switzerland); The Centre of Excellence for Biosensors, Instrumentation and Process Control, Solkan (Slovenia); Mikuljan, Gordan [Laboratory for Synchrotron Radiation, Swiss Light Source, Paul Scherrer Institut, Villigen (Switzerland); Stampanoni, Marco [Laboratory for Synchrotron Radiation, Swiss Light Source, Paul Scherrer Institut, Villigen (Switzerland); Institute for Biomedical Engineering, Swiss Federal Institute of Technology and University of Zurich, Zurich (Switzerland)

    2012-05-01

    A laser-based heating system has been developed at the TOMCAT beamline of the Swiss Light Source for in situ observations of moderate-to-high-temperature applications of materials. Understanding the formation of materials at elevated temperatures is critical for determining their final properties. Synchrotron-based X-ray tomographic microscopy is an ideal technique for studying such processes because high spatial and temporal resolutions are easily achieved and the technique is non-destructive, meaning additional analyses can take place after data collection. To exploit the state-of-the-art capabilities at the tomographic microscopy and coherent radiology experiments (TOMCAT) beamline of the Swiss Light Source, a general-use moderate-to-high-temperature furnace has been developed. Powered by two diode lasers, it provides controlled localized heating, from 673 to 1973 K, to examine many materials systems and their dynamics in real time. The system can also be operated in various thermal modalities. For example, near-isothermal conditions at a given sample location can be achieved with a prescribed time-dependent temperature. This mode is typically used to study isothermal phase transformations; for example, the formation of equiaxed grains in metallic systems or to nucleate and grow bubble foams in silicate melts under conditions that simulate volcanic processes. In another mode, the power of the laser can be fixed and the specimen moved at a constant speed in a user-defined thermal gradient. This is similar to Bridgman solidification, where the thermal gradient and cooling rate control the microstructure formation. This paper details the experimental set-up and provides multiple proofs-of-concept that illustrate the versatility of using this laser-based heating system to explore, in situ, many elevated-temperature phenomena in a variety of materials.

  9. Repeatability and reproducibility of intracellular molar concentration assessed by synchrotron-based x-ray fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Merolle, L., E-mail: lucia.merolle@elettra.eu; Gianoncelli, A. [Elettra - Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy); Malucelli, E., E-mail: emil.malucelli@unibo.it; Cappadone, C.; Farruggia, G.; Sargenti, A.; Procopio, A. [Department of Pharmacy and Biotechnology, University of Bologna, Bologna 40127 (Italy); Fratini, M. [Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Piazza del Viminale 1, 00184 Roma Italy (Italy); Department of Science, Roma Tre University, Via della Vasca Navale 84, I-00146 Rome (Italy); Notargiacomo, A. [Institute for Photonics and Nanotechnology, Consiglio Nazionale delle Richerche, 00156 Rome (Italy); Lombardo, M. [Department of Chemistry “G. Ciamician”, University of Bologna, Bologna 40126 (Italy); Lagomarsino, S. [Institute of Chemical-Physical Processes, Sapienza University of Rome, 00185 Rome (Italy); National Institute of Biostructures and Biosystems, 00136 Rome (Italy); Iotti, S. [Department of Pharmacy and Biotechnology, University of Bologna, Bologna 40127 (Italy); National Institute of Biostructures and Biosystems, 00136 Rome (Italy)

    2016-01-28

    Elemental analysis of biological sample can give information about content and distribution of elements essential for human life or trace elements whose absence is the cause of abnormal biological function or development. However, biological systems contain an ensemble of cells with heterogeneous chemistry and elemental content; therefore, accurate characterization of samples with high cellular heterogeneity may only be achieved by analyzing single cells. Powerful methods in molecular biology are abundant, among them X-Ray microscopy based on synchrotron light source has gaining increasing attention thanks to its extremely sensitivity. However, reproducibility and repeatability of these measurements is one of the major obstacles in achieving a statistical significance in single cells population analysis. In this study, we compared the elemental content of human colon adenocarcinoma cells obtained by three distinct accesses to synchrotron radiation light.

  10. Detailed measurements and shaping of gate profiles for microchannel-plate-based X-ray framing cameras

    International Nuclear Information System (INIS)

    Landen, O.L.; Hammel, B.A.; Bell, P.M.; Abare, A.; Bradley, D.K.; Univ. of Rochester, NY

    1994-01-01

    Gated, microchannel-plate-based (MCP) framing cameras are increasingly used worldwide for x-ray imaging of subnanosecond laser-plasma phenomena. Large dynamic range (> 1,000) measurements of gain profiles for gated microchannel plates (MCP) are presented. Temporal profiles are reconstructed for any point on the microstrip transmission line from data acquired over many shots with variable delay. No evidence for significant pulse distortion by voltage reflections at the ends of the microstrip is observed. The measured profiles compare well to predictions by a time-dependent discrete dynode model down to the 1% level. The calculations do overestimate the contrast further into the temporal wings. The role of electron transit time dispersion in limiting the minimum achievable gate duration is then investigated by using variable duration flattop gating pulses. A minimum gate duration of 50 ps is achieved with flattop gating, consistent with a fractional transit time spread of ∼ 15%

  11. Simultaneous acquisition of dual analyser-based phase contrast X-ray images for small animal imaging

    International Nuclear Information System (INIS)

    Kitchen, Marcus J.; Pavlov, Konstantin M.; Hooper, Stuart B.; Vine, David J.; Siu, Karen K.W.; Wallace, Megan J.; Siew, Melissa L.L.; Yagi, Naoto; Uesugi, Kentaro; Lewis, Rob A.

    2008-01-01

    Analyser-based phase contrast X-ray imaging can provide high-contrast images of biological tissues with exquisite sensitivity to the boundaries between tissues. The phase and absorption information can be extracted by processing multiple images acquired at different analyser orientations. Recording both the transmitted and diffracted beams from a thin Laue analyser crystal can make phase retrieval possible for dynamic systems by allowing full field imaging. This technique was used to image the thorax of a mechanically ventilated newborn rabbit pup using a 25 keV beam from the SPring-8 synchrotron radiation facility. The diffracted image was produced from the (1 1 1) planes of a 50 mm x 40 mm, 100 μm thick Si analyser crystal in the Laue geometry. The beam and analyser were large enough to image the entire chest, making it possible to observe changes in anatomy with high contrast and spatial resolution

  12. Simultaneous acquisition of dual analyser-based phase contrast X-ray images for small animal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kitchen, Marcus J. [School of Physics, Monash University, Victoria 3800 (Australia)], E-mail: Marcus.Kitchen@sci.monash.edu.au; Pavlov, Konstantin M. [School of Physics, Monash University, Victoria 3800 (Australia); Monash Centre for Synchrotron Science, Monash University, Victoria 3800 (Australia); Physics and Electronics, School of Science and Technology, University of New England, NSW 2351 (Australia)], E-mail: Konstantin.Pavlov@sci.monash.edu.au; Hooper, Stuart B. [Department of Physiology, Monash University, Victoria 3800 (Australia)], E-mail: Stuart.Hooper@med.monash.edu.au; Vine, David J. [School of Physics, Monash University, Victoria 3800 (Australia)], E-mail: David.Vine@sci.monash.edu.au; Siu, Karen K.W. [School of Physics, Monash University, Victoria 3800 (Australia); Monash Centre for Synchrotron Science, Monash University, Victoria 3800 (Australia)], E-mail: Karen.Siu@sci.monash.edu.au; Wallace, Megan J. [Department of Physiology, Monash University, Victoria 3800 (Australia)], E-mail: Megan.Wallace@med.monash.edu.au; Siew, Melissa L.L. [Department of Physiology, Monash University, Victoria 3800 (Australia)], E-mail: Melissa.Siew@med.monash.edu.au; Yagi, Naoto [SPring-8/JASRI, Sayo (Japan)], E-mail: yagi@spring8.or.jp; Uesugi, Kentaro [SPring-8/JASRI, Sayo (Japan)], E-mail: ueken@spring8.or.jp; Lewis, Rob A. [School of Physics, Monash University, Victoria 3800 (Australia); Monash Centre for Synchrotron Science, Monash University, Victoria 3800 (Australia)], E-mail: Rob.Lewis@sync.monash.edu.au

    2008-12-15

    Analyser-based phase contrast X-ray imaging can provide high-contrast images of biological tissues with exquisite sensitivity to the boundaries between tissues. The phase and absorption information can be extracted by processing multiple images acquired at different analyser orientations. Recording both the transmitted and diffracted beams from a thin Laue analyser crystal can make phase retrieval possible for dynamic systems by allowing full field imaging. This technique was used to image the thorax of a mechanically ventilated newborn rabbit pup using a 25 keV beam from the SPring-8 synchrotron radiation facility. The diffracted image was produced from the (1 1 1) planes of a 50 mm x 40 mm, 100 {mu}m thick Si analyser crystal in the Laue geometry. The beam and analyser were large enough to image the entire chest, making it possible to observe changes in anatomy with high contrast and spatial resolution.

  13. A simple fracture energy prediction method for fiber network based on its morphological features extracted by X-ray tomography

    International Nuclear Information System (INIS)

    Huang, Xiang; Wang, Qinghui; Zhou, Wei; Li, Jingrong

    2013-01-01

    The fracture behavior of a novel porous metal fiber sintered sheet (PMFSS) was predicted using a semi-empirical method combining the knowledge of its morphological characteristics and micro-mechanical responses. The morphological characteristics were systematically summarized based on the analysis of the topologically identical skeleton representation extracted from the X-ray tomography images. The analytical model firstly proposed by Tan et al. [1] was further modified according to the experimental observations from both tensile tests of single fibers and sintered fiber sheets, which built the coupling of single fiber segment and fiber network in terms of fracture energy using a simple prediction method. The efficacy of the prediction model was verified by comparing the predicted results to the experimental measurements. The prediction error that arose at high porosity was analyzed through fiber orientation distribution. Moreover, the tensile fracture process evolving from single fiber segments at micro-scale to the global mechanical performance was investigated

  14. Synchrotron radiation-based x-ray analysis of bronze artifacts from an Iron Age site in the Judean hills

    International Nuclear Information System (INIS)

    Friedman, E. S.; Brody, A. J.; Young, M. L.; Almer, J. D.; Serge, C. U.; Mini, S. M.

    2008-01-01

    Seven bronze bangles from Tell en-Nasbeh, northern Judah, were investigated to understand the phase composition and manufacturing process of the artifacts, and possibly suggest a provenance for their origin. Synchrotron x-ray radiation diffraction (XRD) and fluorescence (XRF) were used in the analysis to avoid any destructive sampling and at the same time penetrate through the surface into the core metal. These techniques enabled us to determine that the bangles were not just tin bronze, but leaded tin bronze. Based on excavation reports, it is unlikely that the metal objects were manufactured locally at Tell en-Nasbeh; rather, preliminary XRD and XRF data point towards the neighboring region of Edom as their origin. Despite their political enmity during the Iron Age II, the data suggest that Judahite social demands for bronze may have fostered a strong economic relationship between these two polities

  15. Automated IBM PC/XT/AT based measurement and control system for the DRON-3M X-ray diffractometer

    International Nuclear Information System (INIS)

    Tulaev, A.B.

    1989-01-01

    An automated IBM PC/XT/AT based measurement and control system for the DRON-3M X-ray diffractometer is decribed. The system permits carrying out of real time diffractometer control automatic X-spectra measurement and data acquisition, as well as experimental information computing and representation. The electronic of the system consists of a CAMAC crate with analog and power modules, and a control and measurement organization module, performed as a single bord in the standard of PC electronics. The system provides X-spectra acquisition with volume up to 4K in the angle range from 100 to 160 degrees with a resolution of 0.01 degree, a dead time less than 1mks and an exposition time from tenths of a second to dozens of minutes. 3 refs.; 5 figs

  16. How to make x-ray simulation software working on WWW: a simple recipe based on seven years of experience

    International Nuclear Information System (INIS)

    Stepanov, S.

    2004-01-01

    Attaching WWW interfaces to scientific software opens new opportunities to researchers by making their results available to wide scientific community in a way complimentary to publication. We have shown that this task may be much easier than many used to think: the amount of additional code is small, the Common Gateway Interface (CGI) can be written in any language, not necessarily PERL, and the software can be interfaced on any operating system it was originally written and does not have to be ported to UNIX. This paper provides some useful recipes resulted from seven years of author's experience in developing and maintaining highly successful X-ray Web server project. All these solutions are based on free public domain software (Apache, GnuPlot, and InfoZip) and applicable for multiple computer platforms. Some practical examples are provided.

  17. Understanding self ion damage in FCC Ni-Cr-Fe based alloy using X-ray diffraction techniques

    Science.gov (United States)

    Halder Banerjee, R.; Sengupta, P.; Chatterjee, A.; Mishra, S. C.; Bhukta, A.; Satyam, P. V.; Samajdar, I.; Dey, G. K.

    2018-04-01

    Using X-ray diffraction line profile analysis (XRDLPA) approach the radiation response of FCC Ni-Cr-Fe based alloy 690 to 1.5 and 3 MeV Ni2+ ion damage was quantified in terms of its microstructural parameters. These microstructural parameters viz. average domain size, microstrain and dislocation density were found to vary anisotropically with fluence. The anisotropic behaviour is mainly attributable to presence of twins in pre-irradiated microstructure. After irradiation, surface roughness increases as a function of fluence attributable to change in surface and sub-surface morphology caused by displacement cascade, defects and sputtered atoms created by incident energetic ion. The radiation hardening in case of 1.5 MeV Ni2+ irradiated specimens too is a consequence of the increase in dislocation density formed by interaction of radiation induced defects with pre-existing dislocations. At highest fluence there is an initiation of saturation.

  18. Near edge x-ray spectroscopy theory

    International Nuclear Information System (INIS)

    1994-01-01

    We propose to develop a quantitative theory of x-ray spectroscopies in the near edge region, within about 100 eV of threshold. These spectroscopies include XAFS (X-ray absorption fine structure), photoelectron diffraction (PD), and diffraction anomalous fine structure (DAFS), all of which are important tools for structural studies using synchrotron radiation x-ray sources. Of primary importance in these studies are many-body effects, such as the photoelectron self-energy, and inelastic losses. A better understanding of these quantities is needed to obtain theories without adjustable parameters. We propose both analytical and numerical calculations, the latter based on our x-ray spectroscopy codes FEFF

  19. Chest X-Ray

    Medline Plus

    Full Text Available ... Disorders Video: The Basketball Game: An MRI Story Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Chest X-ray Transcript Welcome to Radiology Info dot org! Hello, I’m Dr. Geoffrey ...

  20. Chest X-Ray

    Medline Plus

    Full Text Available ... also be useful to help diagnose and monitor treatment for a variety of lung conditions such as pneumonia, emphysema and cancer. A chest x-ray requires no special preparation. ...