Sample records for x-ray insertion device

  1. Effect of inserted metal at anode tip on formation of pulsed X-ray emitting zone of plasma focus device

    NASA Astrophysics Data System (ADS)

    Miremad, Seyed Milad; Shirani Bidabadi, Babak

    2018-04-01

    The effect of the anode's insert material of a plasma focus device on the properties of X-ray emission zone was studied. Inserts were fabricated out of six different materials including aluminum, copper, zinc, tin, tungsten, and lead to cover a wide range of atomic numbers. For each anode's insert material at different gas pressures and different voltages, the shape of X-ray emission zone was recorded by three pinhole cameras, which were installed on sidewall and roof of the chamber of plasma focus device. The results indicated that by changing the gas pressure and the charge voltage of capacitor, the X-ray source of plasma focus emerges with different forms as a concentrated column or conical shape with sharp or cloudy edges. These structures are in the form of a combination of plasma emission and anode-tip emission with different intensities. These observations indicate that the material of the anode-tip especially affects the structure of X-ray emission zone.

  2. Improvement of the radiographic method for measurement of effective energy of pulsed X-ray emission from a PF device for different anode's insert materials.

    PubMed

    Miremad, Seyed Milad; Shirani, Babak

    2018-06-01

    In this paper, effective energy of pulsed X-Ray emitted from a Mather-type plasma focus device in stored energy of 2.5 kJ with six different anode's insert materials was measured using radiographic method with attenuation filters. Since intensity and energy of X-ray beam were considerably changed with changing the insert material, the method was improved by using different filters simultaneously in all the experiments and selection of the best filter in each experiment according to the appropriate criteria. Effective energy of pulsed X-ray beam was measured 16, 28, 50, 51, 34 and 44 keV when aluminum, copper, zinc, tin, tungsten and lead were used as insert materials, and aluminum, copper, silver, silver, copper and lead were used as filters, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krempasky, J.; Flechsig, U.; Korhonen, T.

    Synchronous monochromator and insertion device energy scans were implemented at the Surfaces/Interfaces:Microscopy (SIM) beamline in order to provide the users fast X-ray magnetic dichroism studies (XMCD). A simple software control scheme is proposed based on a fast monochromator run-time energy readback which quickly updates the insertion device requested energy during an on-the-fly X-ray absorption scan (XAS). In this scheme the Plain Grating Monochromator (PGM) motion control, being much slower compared with the insertion device (APPLE-II type undulator), acts as a 'master' controlling the undulator 'slave' energy position. This master-slave software implementation exploits EPICS distributed device control over computer network andmore » allows for a quasi-synchronous motion control combined with data acquisition needed for the XAS or XMCD experiment.« less

  4. Development of a Hard X-ray Beam Position Monitor for Insertion Device Beams at the APS

    NASA Astrophysics Data System (ADS)

    Decker, Glenn; Rosenbaum, Gerd; Singh, Om

    2006-11-01

    Long-term pointing stability requirements at the Advanced Photon Source (APS) are very stringent, at the level of 500 nanoradians peak-to-peak or better over a one-week time frame. Conventional rf beam position monitors (BPMs) close to the insertion device source points are incapable of assuring this level of stability, owing to mechanical, thermal, and electronic stability limitations. Insertion device gap-dependent systematic errors associated with the present ultraviolet photon beam position monitors similarly limit their ability to control long-term pointing stability. We report on the development of a new BPM design sensitive only to hard x-rays. Early experimental results will be presented.

  5. Effectiveness of electrocardiographic guidance in CVAD tip placement.

    PubMed

    Walker, Graham; Chan, Raymond J; Alexandrou, Evan; Webster, Joan; Rickard, Claire

    International standard practice for the correct confirmation of the central venous access device is the chest X-ray. The intracavitary electrocardiogram-based insertion method is radiation-free, and allows real-time placement verification, providing immediate treatment and reduced requirement for post-procedural repositioning. Relevant databases were searched for prospective randomised controlled trials (RCTs) or quasi RCTs that compared the effectiveness of electrocardiogram-guided catheter tip positioning with placement using surface-anatomy-guided insertion plus chest X-ray confirmation. The primary outcome was accurate catheter tip placement. Secondary outcomes included complications, patient satisfaction and costs. Five studies involving 729 participants were included. Electrocardiogram-guided insertion was more accurate than surface anatomy guided insertion (odds ratio: 8.3; 95% confidence interval (CI) 1.38; 50.07; p=0.02). There was a lack of reporting on complications, patient satisfaction and costs. The evidence suggests that intracavitary electrocardiogram-based positioning is superior to surface-anatomy-guided positioning of central venous access devices, leading to significantly more successful placements. This technique could potentially remove the requirement for post-procedural chest X-ray, especially during peripherally inserted central catheter (PICC) line insertion.

  6. Single-drop optimization of protein crystallization.

    PubMed

    Meyer, Arne; Dierks, Karsten; Hilterhaus, Dierk; Klupsch, Thomas; Mühlig, Peter; Kleesiek, Jens; Schöpflin, Robert; Einspahr, Howard; Hilgenfeld, Rolf; Betzel, Christian

    2012-08-01

    A completely new crystal-growth device has been developed that permits charting a course across the phase diagram to produce crystalline samples optimized for diffraction experiments. The utility of the device is demonstrated for the production of crystals for the traditional X-ray diffraction data-collection experiment, of microcrystals optimal for data-collection experiments at a modern microbeam insertion-device synchrotron beamline and of nanocrystals required for data collection on an X-ray laser beamline.

  7. Soft x-ray spectromicroscopy using compact scanning transmission x-ray microscope at the photon factory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Takeichi, Yasuo, E-mail: yasuo.takeichi@kek.jp; Inami, Nobuhito; Ono, Kanta

    We report the stability and recent performances of a new type of scanning transmission X-ray microscopy. The optics and compact design of the microscope realized mobility and robust performance. Detailed consideration to the vibration control will be described. The insertion device upgraded to elliptical polarization undulator enabled linear dichroism and circular dichroism experiments.

  8. 3D kinematics of mobile-bearing total knee arthroplasty using X-ray fluoroscopy.

    PubMed

    Yamazaki, Takaharu; Futai, Kazuma; Tomita, Tetsuya; Sato, Yoshinobu; Yoshikawa, Hideki; Tamura, Shinichi; Sugamoto, Kazuomi

    2015-04-01

    Total knee arthroplasty (TKA) 3D kinematic analysis requires 2D/3D image registration of X-ray fluoroscopic images and a computer-aided design (CAD) model of the knee implant. However, these techniques cannot provide information on the radiolucent polyethylene insert, since the insert silhouette does not appear clearly in X-ray images. Therefore, it is difficult to obtain the 3D kinematics of the polyethylene insert, particularly the mobile-bearing insert. A technique for 3D kinematic analysis of a mobile-bearing insert used in TKA was developed using X-ray fluoroscopy. The method was tested and a clinical application was evaluated. Tantalum beads and a CAD model of the mobile-bearing TKA insert are used for 3D pose estimation of the mobile-bearing insert used in TKA using X-ray fluoroscopy. The insert model was created using four identical tantalum beads precisely located at known positions in a polyethylene insert using a specially designed insertion device. Finally, the 3D pose of the insert model was estimated using a feature-based 2D/3D registration technique, using the silhouette of beads in fluoroscopic images and the corresponding CAD insert model. In vitro testing for the repeatability of the positioning of the tantalum beads and computer simulations for 3D pose estimation of the mobile-bearing insert were performed. The pose estimation accuracy achieved was sufficient for analyzing mobile-bearing TKA kinematics (RMS error: within 1.0 mm and 1.0°, except for medial-lateral translation). In a clinical application, nine patients with mobile-bearing TKA were investigated and analyzed with respect to a deep knee bending motion. A 3D kinematic analysis technique was developed that enables accurate quantitative evaluation of mobile-bearing TKA kinematics. This method may be useful for improving implant design and optimizing TKA surgical techniques.

  9. New developments in high pressure x-ray spectroscopy beamline at High Pressure Collaborative Access Team

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiao, Y. M., E-mail: yxiao@carnegiescience.edu; Chow, P.; Boman, G.

    The 16 ID-D (Insertion Device - D station) beamline of the High Pressure Collaborative Access Team at the Advanced Photon Source is dedicated to high pressure research using X-ray spectroscopy techniques typically integrated with diamond anvil cells. The beamline provides X-rays of 4.5-37 keV, and current available techniques include X-ray emission spectroscopy, inelastic X-ray scattering, and nuclear resonant scattering. The recent developments include a canted undulator upgrade, 17-element analyzer array for inelastic X-ray scattering, and an emission spectrometer using a polycapillary half-lens. Recent development projects and future prospects are also discussed.

  10. Status of the Superconducting Insertion Device Control at TLS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, K. H.; Wang, C. J.; Lee, Demi

    2007-01-19

    Superconducting insertion devices are installed at Taiwan Light Source to meet the rapidly growing demand of X-ray users. A control system supports the operation of all these superconducting insertion devices. Control system coordinates the operation of the main power supply and the trimming power supply to charge/discharge the magnet and provide essential interlock protection for the coils and vacuum ducts. Quench protection and various cryogenic interlocks are designed to prevent damage to the magnet. A friendly user interface supports routine operation. Various applications are also developed to aid the operation of these insertion devices. Design consideration and details of themore » implementation will be summarized in this report.« less

  11. Structure of Carbon Nanotube Porins in Lipid Bilayers: An in Situ Small-Angle X-ray Scattering (SAXS) Study [Atomic-level structure of carbon nanotube porins in lipid bilayers: an in-situ small-angle x-ray scattering (SAXS) study

    DOE PAGES

    Tran, Ich C.; Tunuguntla, Ramya H.; Kim, Kyunghoon; ...

    2016-06-20

    Carbon nanotube porins (CNTPs), small segments of carbon nanotubes capable of forming defined pores in lipid membranes, are important future components for bionanoelectronic devices as they could provide a robust analog of biological membrane channels. Furthermore, in order to control the incorporation of these CNT channels into lipid bilayers, it is important to understand the structure of the CNTPs before and after insertion into the lipid bilayer as well as the impact of such insertion on the bilayer structure. Here we employed a noninvasive in situ probe, small-angle X-ray scattering, to study the integration of CNT porins into dioleoylphosphatidylcholine bilayers.more » These results show that CNTPs in solution are stabilized by a monolayer of lipid molecules wrapped around their outer surface. We also demonstrate that insertion of CNTPs into the lipid bilayer results in decreased bilayer thickness with the magnitude of this effect increasing with the concentration of CNTPs.« less

  12. A Plasma Focus Device with a 2-MA Discharge Current as a Hard X-Ray Source

    NASA Astrophysics Data System (ADS)

    Yurkov, D. I.; Dulatov, A. K.; Lemeshko, B. D.; Andreev, D. A.; Golikov, A. V.; Mikhailov, Yu. V.; Prokuratov, I. A.; Selifanov, A. N.; Fatiev, T. S.

    2018-04-01

    A device based on a pulsed current generator with capacitive energy storage loaded on a plasma focus (PF) chamber is described. The device provides a discharge current amplitude of up to 2 MA in the PF chamber at a stored energy in the capacitor bank of up to 150 kJ. The PF chamber is designed to study hard X-ray (HXR) emission. It has windows for output of HXR emission in the cathode direction, as well as a special insert for output of HXR emission into the anode cavity. A study of operation of the chamber as a part of the setup with the use of various X-ray targets on the anode has been carried out. At a discharge current of 1.5MA, an HXR pulse with an average duration of 16 ns and energy spectrum from 10 to 200 keV, which provides an absorbed dose in the irradiated samples on the order of 1 Sv, is generated in the PF chamber.

  13. NATIONAL SYNCHROTRON LIGHT SOURCE ACTIVITY REPORT 1998.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    ROTHMAN,E.

    1999-05-01

    In FY 1998, following the 50th Anniversary Year of Brookhaven National Laboratory, Brookhaven Science Associates became the new Managers of BNL. The new start is an appropriate time to take stock of past achievements and to renew or confirm future goals. During the 1998 NSLS Annual Users Meeting (described in Part 3 of this Activity Report), the DOE Laboratory Operations Board, Chaired by the Under Secretary for Energy, Ernest Moniz met at BNL. By chance all the NSLS Chairmen except Martin Blume (acting NSLS Chair 84-85) were present as recorded in the picture. Under their leadership the NSLS has improvedmore » dramatically: (1) The VUV Ring current has increased from 100 mA in October 1982 to nearly 1 A today. For the following few years 10 Ahrs of current were delivered most weeks - NSLS now exceeds that every day. (2) When the first experiments were performed on the X-ray ring during FY1985 the electron energy was 2 GeV and the current up to 100 mA - the X-Ray Ring now runs routinely at 2.5 GeV and at 2.8 GeV with up to 350 mA of current, with a very much longer beam half-life and improved reliability. (3) Starting in FY 1984 the proposal for the Phase II upgrade, mainly for a building extension and a suite of insertion devices and their associated beamlines, was pursued - the promises were delivered in full so that for some years now the NSLS has been running with two undulators in the VUV Ring and three wigglers and an undulator in the X-Ray Ring. In addition two novel insertion devices have been commissioned in the X13 straight. (4) At the start of FY 1998 the NSLS welcomed its 7000th user - attracted by the opportunity for pursuing research with high quality beams, guaranteed not to be interrupted by 'delivery failures', and welcomed by an efficient and caring user office and first class teams of PRT and NSLS staff. R & D have lead to the possibility of running the X-Ray Ring at the higher energy of 2.8 GeV. Figure 1 shows the first user beam, which was provided thereafter for half of the running time in FY 1998. In combination with the development of narrow gap undulators this mode opens the possibility of new undulators which could produce hard X-rays in the fundamental, perhaps up to 10 keV. On 27 September 1998, a low horizontal emittance lattice became operational at 2.584 GeV. This results in approximately a 50% decrease in the horizontal beam-size on dipole bending magnet beamlines, and somewhat less of a decrease on the insertion device lines. The beam lifetime is not degraded by the low emittance lattice. This represents an important achievement, enhancing for all users the x-ray ring brightness. The reduced horizontal emittance electron beam will produce brighter x-ray beams for all the beamlines, both bending magnets and insertion devices, adding to other recent increases in the X-Ray ring brightness. During FY 1999 users will gain experience of the new running mode and plans are in place to do the same at 2.8GeV during further studies sessions. Independent evidence of the reduced emittance is shown in Figure 2. This is a pinhole camera scan showing the X-ray beam profile, obtained on the diagnostic beamline X28. Finally, work has begun to update and refine the proposal of the Phase III upgrade endorsed by the Birgeneau panel and BESAC last year. With the whole NSLS facility in teenage years and with many demonstrated enhancements available, the time has come to herald in the next stage of life at the Light Source.« less

  14. Insertion devices for DORIS III (invited)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pflueger, J.

    1992-01-01

    Recently, a major reconstruction of the electron storage ring DORIS II, the DORIS III project, has been completed (W. Brefeld, H. Nesemann, and J. Rossbach, {ital Proceedings} {ital of} {ital the} {ital European} {ital Particle} {ital Accelerator} {ital Conference}, Rome (World Scientific, Singapore, 1988), p. 2389). Figure 1 shows an overview of the new ring. Originally DORIS II had a twofold symmetry. In part C each of the two dipole magnets adjacing to the 65-m-long straight section was replaced by three corresponding weaker ones. In this way a total of seven straight sections for insertion devices are provided. Six ofmore » them are 4-m long and the one in the center is only 2.7-m long. After extensive discussions with the user groups involved, four x-ray wigglers, one asymmetric hybrid structure, one x-ray undulator, and one XUV multiple undulator of the revolver type have been proposed for six of the sections (J. Pflueger and P. Gurtler, Nucl. Instrum. Methods A {bold 287}, 628 (1990)). One section is presently still free. All devices are either in construction or have already been completed and installed. In this contribution the mechanical and magnetic design of these devices will be described. Results of magnetic measurements of those devices which are already completed will be given in more detail.« less

  15. Engineering solar cells based on correlative X-ray microscopy

    DOE PAGES

    Stuckelberger, Michael; West, Bradley; Nietzold, Tara; ...

    2017-05-01

    In situ and operando measurement techniques combined with nanoscale resolution have proven invaluable in multiple fields of study. We argue that evaluating device performance as well as material behavior by correlative X-ray microscopy with <100 nm resolution can radically change the approach for optimizing absorbers, interfaces and full devices in solar cell research. Here, we thoroughly discuss the measurement technique of X-ray beam induced current and point out fundamental differences between measurements of wafer-based silicon and thin-film solar cells. Based on reports of the last years, we showcase the potential that X-ray microscopy measurements have in combination with in situmore » and operando approaches throughout the solar cell lifecycle: from the growth of individual layers to the performance under operating conditions and degradation mechanisms. Enabled by new developments in synchrotron beamlines, the combination of high spatial resolution with high brilliance and a safe working distance allows for the insertion of measurement equipment that can pave the way for a new class of experiments. When applied to photovoltaics research, we highlight today’s opportunities and challenges in the field of nanoscale X-ray microscopy, and give an outlook on future developments.« less

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stuckelberger, Michael; West, Bradley; Nietzold, Tara

    In situ and operando measurement techniques combined with nanoscale resolution have proven invaluable in multiple fields of study. We argue that evaluating device performance as well as material behavior by correlative X-ray microscopy with <100 nm resolution can radically change the approach for optimizing absorbers, interfaces and full devices in solar cell research. Here, we thoroughly discuss the measurement technique of X-ray beam induced current and point out fundamental differences between measurements of wafer-based silicon and thin-film solar cells. Based on reports of the last years, we showcase the potential that X-ray microscopy measurements have in combination with in situmore » and operando approaches throughout the solar cell lifecycle: from the growth of individual layers to the performance under operating conditions and degradation mechanisms. Enabled by new developments in synchrotron beamlines, the combination of high spatial resolution with high brilliance and a safe working distance allows for the insertion of measurement equipment that can pave the way for a new class of experiments. When applied to photovoltaics research, we highlight today’s opportunities and challenges in the field of nanoscale X-ray microscopy, and give an outlook on future developments.« less

  17. NSLS-II storage ring insertion device and front-end commissioning and operation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, G., E-mail: gwang@bnl.gov; Shaftan, T.; Amundsen, C.

    The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source at Brookhaven National Laboratory. During spring/ summer of 2014, the storage ring was commissioned up to 50 mA without insertion devices. In the fall of 2014, we began commissioning of the project beamlines, which included seven insertion devices on six ID ports. Beamlines IXS, HXN, CSX-1, CSX-2, CHX, SRX, and XPD-1 consist of elliptically polarized undulator (EPU), damping wigglers (DW) and in-vacuum undulators (IVU) covering from VUV to hard x-ray range. In this paper, experience with commissioning and operation is discussed.more » We focus on reaching storage ring performance with IDs, including injection, design emittance, compensation of orbit distortions caused by ID residual field, source point stability, beam alignment and tools for control, monitoring and protection of the ring chambers from ID radiation.« less

  18. Fill-Tube-Induced Mass Perturbations on X-Ray-Driven, Ignition-Scale, Inertial-Confinement-Fusion Capsule Shells and the Implications for Ignition Experiments

    DOE PAGES

    Bennett, G. R.; Herrmann, M. C.; Edwards, M. J.; ...

    2007-11-13

    We present on the first inertial-confinement-fusion ignition facility, the target capsule will be DT filled through a long, narrow tube inserted into the shell. μg-scale shell perturbations Δm' arising from multiple, 10–50 μm-diameter, hollow SiO 2 tubes on x-ray-driven, ignition-scale, 1-mg capsules have been measured on a subignition device. Finally, simulations compare well with observation, whence it is corroborated that Δm' arises from early x-ray shadowing by the tube rather than tube mass coupling to the shell, and inferred that 10–20 μm tubes will negligibly affect fusion yield on a full-ignition facility.

  19. Radiological assessment of placement of the hysteroscopically inserted Essure permanent birth control device.

    PubMed

    Lorente Ramos, R M; Azpeitia Armán, J; Aparicio Rodríguez-Miñón, P; Salazar Arquero, F J; Albillos Merino, J C

    2015-01-01

    Essure is a permanent birth control device that is inserted through the cervix by hysteroscopy. The device is placed in the fallopian tubes, where it causes occlusion by stimulating fibrosis. Patients can be followed up with plain-film X-rays, hysterosalpingography, and ultrasonography, although the devices can also be identified incidentally on CT and MRI. The follow-up of Essure is based on checking the criteria for appropriate positioning and correct functioning (tubal occlusion) and on diagnosing complications. The most common complications are perforation, migration (toward the uterine or peritoneal cavity), and occlusion failure. In hysterosalpingography, vascular intravasation is the most common cause of diagnostic error. Radiologists need to know how to recognize the device on different imaging techniques, how to check that it is correctly placed and functioning, and how to diagnose complications. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  20. Development of a universal medical X-ray imaging phantom prototype.

    PubMed

    Groenewald, Annemari; Groenewald, Willem A

    2016-11-08

    Diagnostic X-ray imaging depends on the maintenance of image quality that allows for proper diagnosis of medical conditions. Maintenance of image quality requires quality assurance programs on the various X-ray modalities, which consist of pro-jection radiography (including mobile X-ray units), fluoroscopy, mammography, and computed tomography (CT) scanning. Currently a variety of modality-specific phantoms are used to perform quality assurance (QA) tests. These phantoms are not only expensive, but suitably trained personnel are needed to successfully use them and interpret the results. The question arose as to whether a single universal phantom could be designed and applied to all of the X-ray imaging modalities. A universal phantom would reduce initial procurement cost, possibly reduce the time spent on QA procedures and simplify training of staff on the single device. The aim of the study was to design and manufacture a prototype of a universal phantom, suitable for image quality assurance in general X-rays, fluoroscopy, mammography, and CT scanning. The universal phantom should be easy to use and would enable automatic data analysis, pass/fail reporting, and corrective action recommendation. In addition, a universal phantom would especially be of value in low-income countries where finances and human resources are limited. The design process included a thorough investigation of commercially available phantoms. Image quality parameters necessary for image quality assurance in the different X-ray imaging modalities were determined. Based on information obtained from the above-mentioned investigations, a prototype of a universal phantom was developed, keeping ease of use and reduced cost in mind. A variety of possible phantom housing and insert materials were investigated, considering physical properties, machinability, and cost. A three-dimensional computer model of the first phantom prototype was used to manufacture the prototype housing and inserts. Some of the inserts were 3D-printed, others were machined from different materials. The different components were assembled to form the first prototype of the universal X-ray imaging phantom. The resulting prototype of the universal phantom conformed to the aims of a single phantom for multiple imag-ing modalities, which would be easy to use and manufacture at a reduced cost. A PCT International Patent Application No. PCT/IB2016/051165 has been filed for this technology. © 2016 The Authors.

  1. A comparative study of scintillator combining methods for flat-panel X-ray image sensors

    NASA Astrophysics Data System (ADS)

    Kim, M. S.; Lim, K. T.; Kim, G.; Cho, G.

    2018-02-01

    An X-ray transmission imaging based on scintillation detection method is the most widely used radiation technique particularly in the medical and industrial areas. As the name suggests, scintillation detection uses a scintillator as an intermediate material to convert incoming radiation into visible-light particles. Among different types of scintillators, CsI(Tl) in a columnar configuration is the most popular type used for applications that require an energy less than 150 keV due to its capability in obtaining a high spatial resolution with a reduced light spreading effect. In this study, different methods in combining a scintillator with a light-receiving unit are investigated and their relationships are given in terms of the image quality. Three different methods of combining a scintillator with a light-receiving unit are selected to investigate their performance in X-ray imaging: upward or downward oriented needles structure of CsI(Tl), coating layer deposition around CsI(Tl), and insertion of FOP. A charge-coupled device was chosen to serve as the light-receiving unit for the proposed system. From the result, the difference of needle directions in CsI(Tl) had no significant effects in the X-ray image. In contrast, deposition of the coating material around CsI(Tl) showed 17.3% reduction in the DQE. Insertion of the FOP increased the spatial resolution by 38%, however, it decreased the light yield in the acquired image by 56%. In order to have the maximum scintillation performance in X-ray imaging, not only the reflection material but also the bonding method must be considered when combining the scintillator with the light-receiving unit. In addition, the use of FOP should be carefully decided based on the purpose of X-ray imaging, e.g., image sharpness or SNR.

  2. Revealing electronic structure changes in Chevrel phase cathodes upon Mg insertion using X-ray absorption spectroscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wan, Liwen F.; Wright, Joshua; Perdue, Brian R.

    Following previous work predicting the electronic response of the Chevrel phase Mo6S8 upon Mg insertion (Thole et al., Phys. Chem. Chem. Phys., 2015, 17, 22548), we provide the experimental proof, evident in X-ray absorption spectroscopy, to illustrate the charge compensation mechanism of the Chevrel phase compound during Mg insertion and de-insertion processes.

  3. X-ray optical simulations supporting advanced commissioning of the coherent hard x-ray beamline at NSLS-II

    NASA Astrophysics Data System (ADS)

    Wiegart, L.; Rakitin, M.; Fluerasu, A.; Chubar, O.

    2017-08-01

    We present the application of fully- and partially-coherent synchrotron radiation wavefront propagation simulation functions, implemented in the "Synchrotron Radiation Workshop" computer code, to create a `virtual beamline' mimicking the Coherent Hard X-ray scattering beamline at NSLS-II. The beamline simulation includes all optical beamline components, such as the insertion device, mirror with metrology data, slits, double crystal monochromator and refractive focusing elements (compound refractive lenses and kinoform lenses). A feature of this beamline is the exploitation of X-ray beam coherence, boosted by the low-emittance NSLS-II storage-ring, for techniques such as X-ray Photon Correlation Spectroscopy or Coherent Diffraction Imaging. The key performance parameters are the degree of Xray beam coherence and photon flux, and the trade-off between them needs to guide the beamline settings for specific experimental requirements. Simulations of key performance parameters are compared to measurements obtained during beamline commissioning, and include the spectral flux of the undulator source, the degree of transverse coherence as well as focal spot sizes.

  4. X-ray grating interferometer for materials-science imaging at a low-coherent wiggler source

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Herzen, Julia; Physics Department and Institute for Medical Engineering, Technische Universitaet Muenchen, 85748 Garching; Donath, Tilman

    2011-11-15

    X-ray phase-contrast radiography and tomography enable to increase contrast for weakly absorbing materials. Recently, x-ray grating interferometers were developed that extend the possibility of phase-contrast imaging from highly brilliant radiation sources like third-generation synchrotron sources to non-coherent conventional x-ray tube sources. Here, we present the first installation of a three grating x-ray interferometer at a low-coherence wiggler source at the beamline W2 (HARWI II) operated by the Helmholtz-Zentrum Geesthacht at the second-generation synchrotron storage ring DORIS (DESY, Hamburg, Germany). Using this type of the wiggler insertion device with a millimeter-sized source allows monochromatic phase-contrast imaging of centimeter sized objects withmore » high photon flux. Thus, biological and materials-science imaging applications can highly profit from this imaging modality. The specially designed grating interferometer currently works in the photon energy range from 22 to 30 keV, and the range will be increased by using adapted x-ray optical gratings. Our results of an energy-dependent visibility measurement in comparison to corresponding simulations demonstrate the performance of the new setup.« less

  5. Inverse Compton scattering X-ray source yield optimization with a laser path folding system inserted in a pre-existent RF linac

    NASA Astrophysics Data System (ADS)

    Chaleil, A.; Le Flanchec, V.; Binet, A.; Nègre, J. P.; Devaux, J. F.; Jacob, V.; Millerioux, M.; Bayle, A.; Balleyguier, P.; Prazeres, R.

    2016-12-01

    An inverse Compton scattering source is under development at the ELSA linac of CEA, Bruyères-le-Châtel. Ultra-short X-ray pulses are produced by inverse Compton scattering of 30 ps-laser pulses by relativistic electron bunches. The source will be able to operate in single shot mode as well as in recurrent mode with 72.2 MHz pulse trains. Within this framework, an optical multipass system that multiplies the number of emitted X-ray photons in both regimes has been designed in 2014, then implemented and tested on ELSA facility in the course of 2015. The device is described from both geometrical and timing viewpoints. It is based on the idea of folding the laser optical path to pile-up laser pulses at the interaction point, thus increasing the interaction probability. The X-ray output gain measurements obtained using this system are presented and compared with calculated expectations.

  6. Trace element abundance determinations by Synchrotron X Ray Fluorescence (SXRF) on returned comet nucleus mineral grains

    NASA Technical Reports Server (NTRS)

    Flynn, G. J.; Sutton, S. R.

    1989-01-01

    Trace element analyses were performed on bulk cosmic dust particles by Proton Induced X Ray Emission (PIXE) and Synchrotron X Ray Fluorescence (SXRF). When present at or near chondritic abundances the trace elements K, Ti, Cr, Mn, Cu, Zn, Ga, Ge, Se, and Br are presently detectable by SXRF in particles of 20 micron diameter. Improvements to the SXRF analysis facility at the National Synchrotron Light Source presently underway should increase the range of detectable elements and permit the analysis of smaller samples. In addition the Advanced Photon Source will be commissioned at Argonne National Laboratory in 1995. This 7 to 8 GeV positron storage ring, specifically designed for high-energy undulator and wiggler insertion devices, will be an ideal source for an x ray microprobe with one micron spatial resolution and better than 100 ppb elemental sensitivity for most elements. Thus trace element analysis of individual micron-sized grains should be possible by the time of the comet nucleus sample return mission.

  7. Catalytic action of β source on x-ray emission from plasma focus

    NASA Astrophysics Data System (ADS)

    Ahmad, S.; Sadiq, Mehboob; Hussain, S.; Shafiq, M.; Zakaullah, M.; Waheed, A.

    2006-01-01

    The influence of preionization around the insulator sleeve by a mesh-type β source (Ni6328) for the x-ray emission from a (2.3-3.9 kJ) plasma focus device is investigated. Quantrad Si p-i-n diodes along with suitable filters are employed as time-resolved x-ray detectors and a multipinhole camera with absorption filters is used for time-integrated analysis. X-ray emission in 4π geometry is measured as a function of argon and hydrogen gas filling pressures with and without β source at different charging voltages. It is found that the pressure range for the x-ray emission is broadened, x-ray emission is enhanced, and shot to shot reproducibility is improved with the β source. With argon, the CuKα emission is estimated to be 27.14 J with an efficiency of 0.7% for β source and 21.5 J with an efficiency of 0.55% without β source. The maximum x-ray yield in 4π geometry is found to be about 68.90 J with an efficiency of 1.8% for β source and 54.58 J with an efficiency of 1.4% without β source. With hydrogen, CuKα emission is 11.82 J with an efficiency of 0.32% for β source and 10.07 J with an efficiency of 0.27% without β source. The maximum x-ray yield in 4π geometry is found to be 30.20 J with an efficiency of 0.77% for β source and 25.58 J with an efficiency of 0.6% without β source. The x-ray emission with Pb insert at the anode tip without β source is also investigated and found to be reproducible and significantly high. The maximum x-ray yield is estimated to be 46.6 J in 4π geometry with an efficiency of 1.4% at 23 kV charging voltage. However, degradation of x-ray yield is observed when charging voltage exceeds 23 kV for Pb insert. From pinhole images it is observed that the x-ray emission due to the bombardment of electrons at the anode tip is dominant in both with and without β source.

  8. Colorimetric carbon dioxide detector to determine accidental tracheal feeding tube placement.

    PubMed

    Howes, Daniel W; Shelley, Eric S; Pickett, William

    2005-04-01

    To determine the accuracy of colorimetric CO2 detection compared to the reference standard two-step radiological confirmation of feeding tube position. A prospective study was conducted with patients presenting to a 21-bed medical-surgical intensive care unit. An adapter was developed using an endotracheal tube adapter to connect a colorimetric CO2 detector to a feeding tube in an airtight manner. In part I of the study a feeding tube connected to the colorimeter was inserted into the endotracheal tubes of ten ventilated patients to test the device's ability to detect tracheal placement. In part II patients undergoing feeding tube insertion had tube position confirmed with the colorimeter as well as the reference standard two-step x-ray. In phase I the colorimeter correctly identified tracheal placement in all ten patients. In phase II 93/100 procedures ultimately were eligible; the colorimeter had a sensitivity of 0.88 (95% confidence interval: 0.65-1.00) and specificity of 0.99 (0.97-1.00). The device missed one of the eight tracheal placements. Agreement between the colorimeter and two-step x-ray interpretations was excellent (Kappa 0.86; standard error 0.10). We describe a novel, convenient method to confirm esophageal feeding tube placement. The device is easily assembled and inexpensive, but should not be reused. Colorimetric determination of tracheal feeding tube placement with this device has excellent agreement with the reference standard two-step radiological technique.

  9. A compact dispersive refocusing Rowland circle X-ray emission spectrometer for laboratory, synchrotron, and XFEL applications

    DOE PAGES

    Holden, William M.; Hoidn, Oliver R.; Ditter, Alexander S.; ...

    2017-07-27

    X-ray emission spectroscopy is emerging as an important complement to x-ray absorption fine structure spectroscopy, providing a characterization of the occupied electronic density of states local to the species of interest. Here, we present details of the design and performance of a compact x-ray emission spectrometer that uses a dispersive refocusing Rowland (DRR) circle geometry to achieve excellent performance for the 2-2.5 keV range, i.e., especially for the K-edge emission from sulfur and phosphorous. The DRR approach allows high energy resolution even for unfocused x-ray sources. This property enables high count rates in laboratory studies, approaching those of insertion-device beamlinesmore » at third-generation synchrotrons, despite use of only a low-powered, conventional x-ray tube. The spectrometer, whose overall scale is set by use of a 10-cm diameter Rowland circle and a new small-pixel complementary metal-oxide-semiconductor x-ray camera, is easily portable to synchrotron or x-ray free electron laser beamlines. Photometrics from measurements at the Advanced Light Source show excellent overall instrumental efficiency. In addition, the compact size of this instrument lends itself to future multiplexing to gain large factors in net collection efficiency or its implementation in controlled gas gloveboxes either in the lab or in an endstation.« less

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dufresne, Eric M.; Dunford, Robert W.; Kanter, Elliot P.

    The performance of a cooled Be compound refractive lens (CRL) has been tested at the Advanced Photon Source (APS) to enable vertical focusing of the pink beam and permit the X-ray beam to spatially overlap with an 80 µm-high low-density plasma that simulates astrophysical environments. Focusing the fundamental harmonics of an insertion device white beam increases the APS power density; here, a power density as high as 500 W mm –2 was calculated. A CRL is chromatic so it does not efficiently focus X-rays whose energies are above the fundamental. Only the fundamental of the undulator focuses at the experiment.more » A two-chopper system reduces the power density on the imaging system and lens by four orders of magnitude, enabling imaging of the focal plane without any X-ray filter. As a result, a method to measure such high power density as well as the performance of the lens in focusing the pink beam is reported.« less

  11. 21 CFR 872.1820 - Dental x-ray exposure alignment device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

  12. 21 CFR 872.1820 - Dental x-ray exposure alignment device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

  13. 21 CFR 872.1820 - Dental x-ray exposure alignment device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

  14. 21 CFR 872.1820 - Dental x-ray exposure alignment device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

  15. 21 CFR 872.1820 - Dental x-ray exposure alignment device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dental x-ray exposure alignment device. 872.1820... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1820 Dental x-ray exposure alignment device. (a) Identification. A dental x-ray exposure alignment device is a device intended to position x...

  16. Establishment of new design criteria for GlidCop ® X-ray absorbers

    DOE PAGES

    Collins, Jeff T.; Nudell, Jeremy; Navrotski, Gary; ...

    2017-02-20

    Here, an engineering research program has been conducted at the Advanced Photon Source (APS) in order to determine the thermomechanical conditions that lead to crack formation in GlidCop ®, a material commonly used to fabricate X-ray absorbers at X-ray synchrotron facilities. This dispersion-strengthened copper alloy is a proprietary material and detailed technical data of interest to the synchrotron community is limited. The results from the research program have allowed new design criteria to be established for GlidCop ® X-ray absorbers based upon the thermomechanically induced fatigue behavior of the material. X-ray power from APS insertion devices was used to exposemore » 30 GlidCop ® samples to 10000 thermal loading cycles each under various beam power conditions, and all of the samples were metallurgically examined for crack presence/geometry. In addition, an independent testing facility was hired to measure temperature-dependent mechanical data and uniaxial mechanical fatigue data for numerous GlidCop ® samples. Data from these studies support finite element analysis (FEA) simulation and parametric models, allowing the development of a thermal fatigue model and the establishment of new design criteria so that the thermomechanically induced fatigue life of X-ray absorbers may be predicted. It is also demonstrated how the thermal fatigue model can be used as a tool to geometrically optimize X-ray absorber designs.« less

  17. Establishment of new design criteria for GlidCop ® X-ray absorbers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Collins, Jeff T.; Nudell, Jeremy; Navrotski, Gary

    Here, an engineering research program has been conducted at the Advanced Photon Source (APS) in order to determine the thermomechanical conditions that lead to crack formation in GlidCop ®, a material commonly used to fabricate X-ray absorbers at X-ray synchrotron facilities. This dispersion-strengthened copper alloy is a proprietary material and detailed technical data of interest to the synchrotron community is limited. The results from the research program have allowed new design criteria to be established for GlidCop ® X-ray absorbers based upon the thermomechanically induced fatigue behavior of the material. X-ray power from APS insertion devices was used to exposemore » 30 GlidCop ® samples to 10000 thermal loading cycles each under various beam power conditions, and all of the samples were metallurgically examined for crack presence/geometry. In addition, an independent testing facility was hired to measure temperature-dependent mechanical data and uniaxial mechanical fatigue data for numerous GlidCop ® samples. Data from these studies support finite element analysis (FEA) simulation and parametric models, allowing the development of a thermal fatigue model and the establishment of new design criteria so that the thermomechanically induced fatigue life of X-ray absorbers may be predicted. It is also demonstrated how the thermal fatigue model can be used as a tool to geometrically optimize X-ray absorber designs.« less

  18. 21 CFR 872.1840 - Dental x-ray position indicating device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dental x-ray position indicating device. 872.1840... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1840 Dental x-ray position indicating device. (a) Identification. A dental x-ray position indicating device is a device, such as a collimator...

  19. 21 CFR 872.1840 - Dental x-ray position indicating device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dental x-ray position indicating device. 872.1840... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1840 Dental x-ray position indicating device. (a) Identification. A dental x-ray position indicating device is a device, such as a collimator...

  20. 21 CFR 872.1840 - Dental x-ray position indicating device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dental x-ray position indicating device. 872.1840... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1840 Dental x-ray position indicating device. (a) Identification. A dental x-ray position indicating device is a device, such as a collimator...

  1. 21 CFR 872.1840 - Dental x-ray position indicating device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dental x-ray position indicating device. 872.1840... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1840 Dental x-ray position indicating device. (a) Identification. A dental x-ray position indicating device is a device, such as a collimator...

  2. 21 CFR 872.1840 - Dental x-ray position indicating device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental x-ray position indicating device. 872.1840... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1840 Dental x-ray position indicating device. (a) Identification. A dental x-ray position indicating device is a device, such as a collimator...

  3. 21 CFR 892.1610 - Diagnostic x-ray beam-limiting device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Diagnostic x-ray beam-limiting device. 892.1610... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1610 Diagnostic x-ray beam-limiting device. (a) Identification. A diagnostic x-ray beam-limiting device is a device such as a collimator, a...

  4. 21 CFR 892.1610 - Diagnostic x-ray beam-limiting device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic x-ray beam-limiting device. 892.1610... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1610 Diagnostic x-ray beam-limiting device. (a) Identification. A diagnostic x-ray beam-limiting device is a device such as a collimator, a...

  5. 21 CFR 892.1610 - Diagnostic x-ray beam-limiting device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Diagnostic x-ray beam-limiting device. 892.1610... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1610 Diagnostic x-ray beam-limiting device. (a) Identification. A diagnostic x-ray beam-limiting device is a device such as a collimator, a...

  6. 21 CFR 892.1610 - Diagnostic x-ray beam-limiting device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic x-ray beam-limiting device. 892.1610... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1610 Diagnostic x-ray beam-limiting device. (a) Identification. A diagnostic x-ray beam-limiting device is a device such as a collimator, a...

  7. 21 CFR 892.1610 - Diagnostic x-ray beam-limiting device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Diagnostic x-ray beam-limiting device. 892.1610... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1610 Diagnostic x-ray beam-limiting device. (a) Identification. A diagnostic x-ray beam-limiting device is a device such as a collimator, a...

  8. Three-dimensional kinematic estimation of mobile-bearing total knee arthroplasty from x-ray fluoroscopic images

    NASA Astrophysics Data System (ADS)

    Yamazaki, Takaharu; Futai, Kazuma; Tomita, Tetsuya; Sato, Yoshinobu; Yoshikawa, Hideki; Tamura, Shinichi; Sugamoto, Kazuomi

    2011-03-01

    To achieve 3D kinematic analysis of total knee arthroplasty (TKA), 2D/3D registration techniques, which use X-ray fluoroscopic images and computer-aided design (CAD) model of the knee implant, have attracted attention in recent years. These techniques could provide information regarding the movement of radiopaque femoral and tibial components but could not provide information of radiolucent polyethylene insert, because the insert silhouette on X-ray image did not appear clearly. Therefore, it was difficult to obtain 3D kinemaitcs of polyethylene insert, particularly mobile-bearing insert that move on the tibial component. This study presents a technique and the accuracy for 3D kinematic analysis of mobile-bearing insert in TKA using X-ray fluoroscopy, and finally performs clinical applications. For a 3D pose estimation technique of the mobile-bearing insert in TKA using X-ray fluoroscopy, tantalum beads and CAD model with its beads are utilized, and the 3D pose of the insert model is estimated using a feature-based 2D/3D registration technique. In order to validate the accuracy of the present technique, experiments including computer simulation test were performed. The results showed the pose estimation accuracy was sufficient for analyzing mobile-bearing TKA kinematics (the RMS error: about 1.0 mm, 1.0 degree). In the clinical applications, seven patients with mobile-bearing TKA in deep knee bending motion were studied and analyzed. Consequently, present technique enables us to better understand mobile-bearing TKA kinematics, and this type of evaluation was thought to be helpful for improving implant design and optimizing TKA surgical techniques.

  9. 21 CFR 872.1810 - Intraoral source x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Intraoral source x-ray system. 872.1810 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1810 Intraoral source x-ray system. (a) Identification. An intraoral source x-ray system is an electrically powered device that produces x-rays and is...

  10. 21 CFR 872.1810 - Intraoral source x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraoral source x-ray system. 872.1810 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1810 Intraoral source x-ray system. (a) Identification. An intraoral source x-ray system is an electrically powered device that produces x-rays and is...

  11. 21 CFR 872.1810 - Intraoral source x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Intraoral source x-ray system. 872.1810 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1810 Intraoral source x-ray system. (a) Identification. An intraoral source x-ray system is an electrically powered device that produces x-rays and is...

  12. 21 CFR 872.1810 - Intraoral source x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Intraoral source x-ray system. 872.1810 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1810 Intraoral source x-ray system. (a) Identification. An intraoral source x-ray system is an electrically powered device that produces x-rays and is...

  13. Attenuation characteristics of fiberoptic plates for digital mammography and other X-ray imaging applications.

    PubMed

    Vedantham, S; Karellas, A; Suryanarayanan, S

    2003-01-01

    Spatially coherent fiberoptic plates are important components of some charge-coupled device (CCD)-based x-ray imaging systems. These plates efficiently transmit scintillations from the phosphor, and also filter out x-rays not absorbed by the phosphor, thus protecting the CCD from direct x-ray interaction. The thickness of the fiberoptic plate and the CCD package present a significant challenge in the design of a digital x-ray cassette capable of insertion into the existing film-screen cassette holders of digital mammography systems. This study was performed with an aim to optimize fiberoptic plate thickness. Attenuation measurements were performed on nine fiberoptic plates varying in material composition that exhibit desirable optical characteristics such as good coupling efficiency. Mammographic spectra from a clinical mammographic system and an Americium-241 (Am-241) source (59.54 KeV) were used. The spectra were recorded with a high-resolution cadmium zinc telluride (CZT)-based spectrometer and corrected for dead time and pile-up. The linear attenuation coefficients varied by a factor of 3 in the set of tested fiberoptic plates at both mammographic energies and 59.54 keV. Our results suggest that a 3-mm thick high-absorption plate might provide adequate for shielding at mammographic energies. A thickness of 2-mm is feasible for mammographic applications with further optimization of the fiberoptic plate composition by incorporating non-scintillating, high-atomic number material. This would allow more space for cooling components of the cassette and for a more compact device, which is critical for clinical implementation of the technology.

  14. 21 CFR 872.1905 - Dental x-ray film holder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dental x-ray film holder. 872.1905 Section 872...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1905 Dental x-ray film holder. (a) Identification. A dental x-ray film holder is a device intended to position and to hold x-ray film inside the mouth...

  15. 21 CFR 872.1905 - Dental x-ray film holder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dental x-ray film holder. 872.1905 Section 872...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1905 Dental x-ray film holder. (a) Identification. A dental x-ray film holder is a device intended to position and to hold x-ray film inside the mouth...

  16. 21 CFR 872.1905 - Dental x-ray film holder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dental x-ray film holder. 872.1905 Section 872...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1905 Dental x-ray film holder. (a) Identification. A dental x-ray film holder is a device intended to position and to hold x-ray film inside the mouth...

  17. 21 CFR 872.1905 - Dental x-ray film holder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dental x-ray film holder. 872.1905 Section 872...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1905 Dental x-ray film holder. (a) Identification. A dental x-ray film holder is a device intended to position and to hold x-ray film inside the mouth...

  18. 21 CFR 872.1905 - Dental x-ray film holder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental x-ray film holder. 872.1905 Section 872...) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1905 Dental x-ray film holder. (a) Identification. A dental x-ray film holder is a device intended to position and to hold x-ray film inside the mouth...

  19. 21 CFR 872.1800 - Extraoral source x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Extraoral source x-ray system. 872.1800 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1800 Extraoral source x-ray system. (a) Identification. An extraoral source x-ray system is an AC-powered device that produces x-rays and is intended for...

  20. 21 CFR 872.1800 - Extraoral source x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Extraoral source x-ray system. 872.1800 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1800 Extraoral source x-ray system. (a) Identification. An extraoral source x-ray system is an AC-powered device that produces x-rays and is intended for...

  1. 21 CFR 872.1800 - Extraoral source x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Extraoral source x-ray system. 872.1800 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1800 Extraoral source x-ray system. (a) Identification. An extraoral source x-ray system is an AC-powered device that produces x-rays and is intended for...

  2. The intracavitary ECG method for positioning the tip of central venous access devices in pediatric patients: results of an Italian multicenter study.

    PubMed

    Rossetti, Francesca; Pittiruti, Mauro; Lamperti, Massimo; Graziano, Ugo; Celentano, Davide; Capozzoli, Giuseppe

    2015-01-01

    The Italian Group for Venous Access Devices (GAVeCeLT) has carried out a multicenter study investigating the safety and accuracy of intracavitary electrocardiography (IC-ECG) in pediatric patients. We enrolled 309 patients (age 1 month-18 years) candidate to different central venous access devices (VAD) - 56 peripherally inserted central catheters (PICC), 178 short term centrally inserted central catheters (CICC), 65 long term VADs, 10 VADs for dialysis - in five Italian Hospitals. Three age groups were considered: A (<4 years, n = 157), B (4-11 years, n = 119), and C (12-18 years, n = 31). IC-ECG was applicable in 307 cases. The increase of the P wave on IC-ECG was detected in all cases but two. The tip of the catheter was positioned at the cavo-atrial junction (CAJ) (i.e., at the maximal height of the P wave on IC-ECG) and the position was checked during the procedure by fluoroscopy or chest x-ray, considering the CAJ at 1-2 cm (group A), 1.5-3 cm (group B), or 2-4 cm (group C) below the carina. There were no complications related to IC-ECG. The overall match between IC-ECG and x-ray was 95.8% (96.2% in group A, 95% in group B, and 96.8% in group C). In 95 cases, the IC-ECG was performed with a dedicated ECG monitor, specifically designed for IC-ECG (Nautilus, Romedex): in this group, the match between IC-ECG and x-ray was 98.8%. We conclude that the IC-ECG method is safe and accurate in the pediatric patients. The applicability of the method is 99.4% and its feasibility is 99.4%. The accuracy is 95.8% and even higher (98.8%) when using a dedicated ECG monitor.

  3. Microfluidic devices fabricated in poly(methyl methacrylate) using hot-embossing with integrated sampling capillary and fiber optics for fluorescence detection.

    PubMed

    Qi, Shize; Liu, Xuezhu; Ford, Sean; Barrows, James; Thomas, Gloria; Kelly, Kevin; McCandless, Andrew; Lian, Kun; Goettert, Jost; Soper, Steven A

    2002-05-01

    High-aspect-ratio microstructures have been prepared using hot-embossing techniques in poly(methyl methacrylate) (PMMA) from Ni-based molding dies prepared using LIGA (Lithographie, Galvanoformung, Abformung). Due to the small amount of mask undercutting associated with X-ray lithography and the high energy X-ray beam used during photoresist patterning, deep structures with sharp and smooth sidewalls have been prepared. The Ni-electroforms produced devices with minimal replication errors using hot-embossing at a turn around time of approximately 5 min per device. In addition, several different polymers (with different glass transition temperatures) could be effectively molded with these Ni-electroforms and many devices (>300) molded with the same master without any noticeable degradation. The PMMA devices consisted of deep and narrow channels for insertion of a capillary for the automated electrokinetic loading of sample into the microfluidic device and also, a pair of optical fibers for shuttling laser light to the detection zone and collecting the resulting emission for fluorescence analysis. Electrophoretic separations of double-stranded DNA ladders Phi X174 digested with Hae III) were performed with fluorescence detection accomplished using near-IR excitation. It was found that the narrow width of the channels did not contribute significantly to electrophoretic zone broadening and the plate numbers generated in the extended length separation channel allowed sorting of the 271/281 base pair fragments associated with this sizing ladder when electrophoresed in methylcellulose entangled polymer solutions. The dual fiber detector produced sub-attomole detection limits with the entire detector, including laser source, electronics and photon transducer, situated in a single box measuring 3'' x 10" x 14".

  4. Diamond-anvil high-pressure cell with improved X-ray collimation system

    DOEpatents

    Schiferl, David; Olinger, Barton W.; Livingston, Robert W.

    1986-01-01

    An adjustable X-ray collimation system for a diamond-anvil high-pressure cell of the type including a cooperable piston and cylinder and a pair of opposing diamonds located between the head of the piston and the head of the cylinder. The X-ray collimation system includes a tubular insert which contains an X-ray collimator. The insert is engageable in the bore of the piston. The collimator is mounted within the insert by means of an elastomeric O-ring at the end closest the opposed diamonds, and by means of a set of adjustable set screws at the opposite end. By adjustment of the set screws the collimator can be pivoted about the O-ring and brought into alignment with the opposed diamonds and the sample contained therein. In the preferred embodiment there is further provided a set of plugs which are insertable in the bore of the collimator. The plugs have bores of different diameters. By successively inserting plugs of progressively smaller bore diameters and adjusting the alignment of the collimator with each plug, the collimator can be quickly brought into accurate alignment with the diamonds. The collimation system allows alignment of the collimator either before or after the cell has been loaded and pressurized.

  5. Diamond-anvil high-pressure cell with improved x-ray collimation system

    DOEpatents

    Schiferl, D.; Olinger, B.W.; Livingston, R.W.

    1984-03-30

    An adjustable x-ray collimation system for a diamond-anvil high-pressure cell of the type including a cooperable piston and cylinder and a pair of opposing diamonds located between the head of the piston and the head of the cylinder. The x-ray collimation system includes a tubular insert which contains an x-ray collimator. The insert is engageable in the bore of the piston. The collimator is mounted within the insert by means of an elastomeric o-ring at the end closest the opposed diamonds, and by means of a set of adjustable set screws at the opposite end. By adjustment of the set screws the collimator can be pivoted about the o-ring and brought into alignment with the opposed diamonds and the sample contained therein. In the preferred embodiment there is further provided a set of plugs which are insertable in the bore of the collimator. The plugs have bores of different diameters. By successively inserting plugs of progressively smaller bore diameters and adjusting the alignment of the collimator with each plug, the collimator can be quickly brought into accurate alignment with the diamonds. The collimation system allows alignment of the collimator either before or after the cell has been loaded and pressurized.

  6. Pink-beam focusing with a one-dimensional compound refractive lens

    DOE PAGES

    Dufresne, Eric M.; Dunford, Robert W.; Kanter, Elliot P.; ...

    2016-07-28

    The performance of a cooled Be compound refractive lens (CRL) has been tested at the Advanced Photon Source (APS) to enable vertical focusing of the pink beam and permit the X-ray beam to spatially overlap with an 80 µm-high low-density plasma that simulates astrophysical environments. Focusing the fundamental harmonics of an insertion device white beam increases the APS power density; here, a power density as high as 500 W mm –2 was calculated. A CRL is chromatic so it does not efficiently focus X-rays whose energies are above the fundamental. Only the fundamental of the undulator focuses at the experiment.more » A two-chopper system reduces the power density on the imaging system and lens by four orders of magnitude, enabling imaging of the focal plane without any X-ray filter. As a result, a method to measure such high power density as well as the performance of the lens in focusing the pink beam is reported.« less

  7. 21 CFR 892.1630 - Electrostatic x-ray imaging system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Electrostatic x-ray imaging system. 892.1630... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1630 Electrostatic x-ray imaging system. (a) Identification. An electrostatic x-ray imaging system is a device intended for medical...

  8. 21 CFR 892.1630 - Electrostatic x-ray imaging system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Electrostatic x-ray imaging system. 892.1630... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1630 Electrostatic x-ray imaging system. (a) Identification. An electrostatic x-ray imaging system is a device intended for medical...

  9. 21 CFR 892.1770 - Diagnostic x-ray tube mount.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Diagnostic x-ray tube mount. 892.1770 Section 892...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1770 Diagnostic x-ray tube mount. (a) Identification. A diagnostic x-ray tube mount is a device intended to support and to position the diagnostic x...

  10. 21 CFR 892.1770 - Diagnostic x-ray tube mount.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic x-ray tube mount. 892.1770 Section 892...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1770 Diagnostic x-ray tube mount. (a) Identification. A diagnostic x-ray tube mount is a device intended to support and to position the diagnostic x...

  11. 21 CFR 892.1770 - Diagnostic x-ray tube mount.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic x-ray tube mount. 892.1770 Section 892...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1770 Diagnostic x-ray tube mount. (a) Identification. A diagnostic x-ray tube mount is a device intended to support and to position the diagnostic x...

  12. 21 CFR 892.1770 - Diagnostic x-ray tube mount.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Diagnostic x-ray tube mount. 892.1770 Section 892...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1770 Diagnostic x-ray tube mount. (a) Identification. A diagnostic x-ray tube mount is a device intended to support and to position the diagnostic x...

  13. 21 CFR 892.1770 - Diagnostic x-ray tube mount.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Diagnostic x-ray tube mount. 892.1770 Section 892...) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1770 Diagnostic x-ray tube mount. (a) Identification. A diagnostic x-ray tube mount is a device intended to support and to position the diagnostic x...

  14. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube encased...

  15. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube encased...

  16. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube encased...

  17. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube encased...

  18. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube encased...

  19. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube encased...

  20. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube encased...

  1. 21 CFR 892.5930 - Therapeutic x-ray tube housing assembly.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Therapeutic x-ray tube housing assembly. 892.5930... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5930 Therapeutic x-ray tube housing assembly. (a) Identification. A therapeutic x-ray tube housing assembly is an x-ray generating tube encased...

  2. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube encased...

  3. 21 CFR 892.1760 - Diagnostic x-ray tube housing assembly.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic x-ray tube housing assembly. 892.1760... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1760 Diagnostic x-ray tube housing assembly. (a) Identification. A diagnostic x-ray tube housing assembly is an x-ray generating tube encased...

  4. X-ray compass for determining device orientation

    DOEpatents

    Da Silva, Luiz B.; Matthews, Dennis L.; Fitch, Joseph P.; Everett, Matthew J.; Colston, Billy W.; Stone, Gary F.

    1999-01-01

    An apparatus and method for determining the orientation of a device with respect to an x-ray source. In one embodiment, the present invention is coupled to a medical device in order to determine the rotational orientation of the medical device with respect to the x-ray source. In such an embodiment, the present invention is comprised of a scintillator portion which is adapted to emit photons upon the absorption of x-rays emitted from the x-ray source. An x-ray blocking portion is coupled to the scintillator portion. The x-ray blocking portion is disposed so as to vary the quantity of x-rays which penetrate the scintillator portion based upon the particular rotational orientation of the medical device with respect to the x-ray source. A photon transport mechanism is also coupled to the scintillator portion. The photon transport mechanism is adapted to pass the photons emitted from the scintillator portion to an electronics portion. By analyzing the quantity of the photons, the electronics portion determines the rotational orientation of the medical device with respect to the x-ray source.

  5. X-ray compass for determining device orientation

    DOEpatents

    Da Silva, L.B.; Matthews, D.L.; Fitch, J.P.; Everett, M.J.; Colston, B.W.; Stone, G.F.

    1999-06-15

    An apparatus and method for determining the orientation of a device with respect to an x-ray source are disclosed. In one embodiment, the present invention is coupled to a medical device in order to determine the rotational orientation of the medical device with respect to the x-ray source. In such an embodiment, the present invention is comprised of a scintillator portion which is adapted to emit photons upon the absorption of x-rays emitted from the x-ray source. An x-ray blocking portion is coupled to the scintillator portion. The x-ray blocking portion is disposed so as to vary the quantity of x-rays which penetrate the scintillator portion based upon the particular rotational orientation of the medical device with respect to the x-ray source. A photon transport mechanism is also coupled to the scintillator portion. The photon transport mechanism is adapted to pass the photons emitted from the scintillator portion to an electronics portion. By analyzing the quantity of the photons, the electronics portion determines the rotational orientation of the medical device with respect to the x-ray source. 25 figs.

  6. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Diagnostic x-ray high voltage generator. 892.1700... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1700 Diagnostic x-ray high voltage generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended to...

  7. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Diagnostic x-ray high voltage generator. 892.1700... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1700 Diagnostic x-ray high voltage generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended to...

  8. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic x-ray high voltage generator. 892.1700... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1700 Diagnostic x-ray high voltage generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended to...

  9. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Diagnostic x-ray high voltage generator. 892.1700... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1700 Diagnostic x-ray high voltage generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended to...

  10. 21 CFR 892.1700 - Diagnostic x-ray high voltage generator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic x-ray high voltage generator. 892.1700... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1700 Diagnostic x-ray high voltage generator. (a) Identification. A diagnostic x-ray high voltage generator is a device that is intended to...

  11. Properties of the insertion devices for PETRA III and its extension

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schöps, A., E-mail: andreas.schoeps@desy.de; Vagin, P.; Tischer, M., E-mail: markus.tischer@desy.de

    DESY presently operates 14 independent insertion device (ID) beamlines at its 6 GeV storage ring PETRA III. Besides the 2 m long standard undulators U29 and U32, several special IDs of up to 5 m length have been installed to meet the experimental requests for high energy X-rays, elliptically polarized light, and a higher degree of coherence. Two additional half octants of the ring have recently been reconstructed, in order to extend the experimental capabilities at PETRA III. The straight sections also allow for installation of IDs of 2 m or 5 m length. This article gives an overview ofmore » the ID key parameters, the spectral properties and the brilliance of the current undulators installed at PETRA III. It also presents the characteristics of some of the upcoming special IDs, like in-vacuum and short undulators.« less

  12. A Fast, Accurate and Easy to Implement Method for Pose Recognition of an Intramedullary Nail using a Tracked C-arm

    NASA Astrophysics Data System (ADS)

    Esfandiari, H.; Amiri, S.; Lichti, D. D.; Anglin, C.

    2014-06-01

    A C-arm is a mobile X-ray device that is frequently used during orthopaedic surgeries. It consists of a semi-circular, arc-shaped arm that holds an X-ray transmitter at one end and an X-ray detector at the other. Intramedullary nail (IM nail) fixation is a popular orthopaedic surgery in which a metallic rod is placed into the patient's fractured bone (femur or tibia) and fixed using metal screws. The main challenge of IM-nail fixation surgery is to achieve the X-ray shot in which the distal holes of the IM nail appear as circles (desired view) so that the surgeon can easily insert the screws. Although C-arm X-ray devices are routinely used in IM-nail fixation surgeries, the surgeons or radiation technologists (rad-techs) usually use it in a trial-and-error manner. This method raises both radiation exposure and surgery time. In this study, we have designed and developed an IM-nail distal locking navigation technique that leads to more accurate and faster screw placement with a lower radiation dose and a minimum number of added steps to the operation to make it more accepted within the orthopaedic community. The specific purpose of this study was to develop and validate an automated technique for identifying the current pose of the IM nail relative to the C-arm. An accuracy assessment was performed to test the reliability of the navigation results. Translational accuracy was demonstrated to be better than 1 mm, roll and pitch rotations better than 2° and yaw rotational accuracy better than 2-5° depending on the separate angle. Computation time was less than 3.5 seconds.

  13. Main functions, recent updates, and applications of Synchrotron Radiation Workshop code

    NASA Astrophysics Data System (ADS)

    Chubar, Oleg; Rakitin, Maksim; Chen-Wiegart, Yu-Chen Karen; Chu, Yong S.; Fluerasu, Andrei; Hidas, Dean; Wiegart, Lutz

    2017-08-01

    The paper presents an overview of the main functions and new application examples of the "Synchrotron Radiation Workshop" (SRW) code. SRW supports high-accuracy calculations of different types of synchrotron radiation, and simulations of propagation of fully-coherent radiation wavefronts, partially-coherent radiation from a finite-emittance electron beam of a storage ring source, and time-/frequency-dependent radiation pulses of a free-electron laser, through X-ray optical elements of a beamline. An extended library of physical-optics "propagators" for different types of reflective, refractive and diffractive X-ray optics with its typical imperfections, implemented in SRW, enable simulation of practically any X-ray beamline in a modern light source facility. The high accuracy of calculation methods used in SRW allows for multiple applications of this code, not only in the area of development of instruments and beamlines for new light source facilities, but also in areas such as electron beam diagnostics, commissioning and performance benchmarking of insertion devices and individual X-ray optical elements of beamlines. Applications of SRW in these areas, facilitating development and advanced commissioning of beamlines at the National Synchrotron Light Source II (NSLS-II), are described.

  14. 21 CFR 892.1620 - Cine or spot fluorographic x-ray camera.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cine or spot fluorographic x-ray camera. 892.1620... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1620 Cine or spot fluorographic x-ray camera. (a) Identification. A cine or spot fluorographic x-ray camera is a device intended to photograph...

  15. 21 CFR 892.1620 - Cine or spot fluorographic x-ray camera.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cine or spot fluorographic x-ray camera. 892.1620... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1620 Cine or spot fluorographic x-ray camera. (a) Identification. A cine or spot fluorographic x-ray camera is a device intended to photograph...

  16. 21 CFR 892.1620 - Cine or spot fluorographic x-ray camera.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cine or spot fluorographic x-ray camera. 892.1620... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1620 Cine or spot fluorographic x-ray camera. (a) Identification. A cine or spot fluorographic x-ray camera is a device intended to photograph...

  17. 21 CFR 892.1620 - Cine or spot fluorographic x-ray camera.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cine or spot fluorographic x-ray camera. 892.1620... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1620 Cine or spot fluorographic x-ray camera. (a) Identification. A cine or spot fluorographic x-ray camera is a device intended to photograph...

  18. 21 CFR 892.1620 - Cine or spot fluorographic x-ray camera.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cine or spot fluorographic x-ray camera. 892.1620... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1620 Cine or spot fluorographic x-ray camera. (a) Identification. A cine or spot fluorographic x-ray camera is a device intended to photograph...

  19. An update on carbon nanotube-enabled X-ray sources for biomedical imaging.

    PubMed

    Puett, Connor; Inscoe, Christina; Hartman, Allison; Calliste, Jabari; Franceschi, Dora K; Lu, Jianping; Zhou, Otto; Lee, Yueh Z

    2018-01-01

    A new imaging technology has emerged that uses carbon nanotubes (CNT) as the electron emitter (cathode) for the X-ray tube. Since the performance of the CNT cathode is controlled by simple voltage manipulation, CNT-enabled X-ray sources are ideal for the repetitive imaging steps needed to capture three-dimensional information. As such, they have allowed the development of a gated micro-computed tomography (CT) scanner for small animal research as well as stationary tomosynthesis, an experimental technology for large field-of-view human imaging. The small animal CT can acquire images at specific points in the respiratory and cardiac cycles. Longitudinal imaging therefore becomes possible and has been applied to many research questions, ranging from tumor response to the noninvasive assessment of cardiac output. Digital tomosynthesis (DT) is a low-dose and low-cost human imaging tool that captures some depth information. Known as three-dimensional mammography, DT is now used clinically for breast imaging. However, the resolution of currently-approved DT is limited by the need to swing the X-ray source through space to collect a series of projection views. An array of fixed and distributed CNT-enabled sources provides the solution and has been used to construct stationary DT devices for breast, lung, and dental imaging. To date, over 100 patients have been imaged on Institutional Review Board-approved study protocols. Early experience is promising, showing an excellent conspicuity of soft-tissue features, while also highlighting technical and post-acquisition processing limitations that are guiding continued research and development. Additionally, CNT-enabled sources are being tested in miniature X-ray tubes that are capable of generating adequate photon energies and tube currents for clinical imaging. Although there are many potential applications for these small field-of-view devices, initial experience has been with an X-ray source that can be inserted into the mouth for dental imaging. Conceived less than 20 years ago, CNT-enabled X-ray sources are now being manufactured on a commercial scale and are powering both research tools and experimental human imaging devices. WIREs Nanomed Nanobiotechnol 2018, 10:e1475. doi: 10.1002/wnan.1475 This article is categorized under: Diagnostic Tools > Diagnostic Nanodevices Diagnostic Tools > In Vivo Nanodiagnostics and Imaging. © 2017 Wiley Periodicals, Inc.

  20. [Study on Intelligent Automatic Tracking Radiation Protection Curtain].

    PubMed

    Zhao, Longyang; Han, Jindong; Ou, Minjian; Chen, Jinlong

    2015-09-01

    In order to overcome the shortcomings of traditional X-ray inspection taking passive protection mode, this paper combines the automatic control technology, puts forward a kind of active protection X-ray equipment. The device of automatic detection of patients receiving X-ray irradiation part, intelligent adjustment in patients and shooting device between automatic tracking radiation protection device height. The device has the advantages of automatic adjustment, anti-radiation device, reduce the height of non-irradiated area X-ray radiation and improve the work efficiency. Testing by the professional organization, the device can decrease more than 90% of X-ray dose for patients with non-irradiated area.

  1. Statistical and operational considerations for designs for x-ray tomographic spectrophotometry to detect, localize, and classify foreign objects in various systems

    NASA Astrophysics Data System (ADS)

    Fennelly, Alphonsus J.; Fry, Edward L.; Zukic, Muamer; Wilson, Michele M.; Janik, Tadeusz J.; Torr, Douglas G.

    1994-11-01

    In six companion papers we discuss a capability for x-ray tomographic spectrophotometry at three energy ranges to observe foreign objects in various systems using a novel x-ray optical and photometric approach. We describe new types of thin-film x-ray reflecting filters to provide energy-specific optical trains, inserted into existing x-ray interrogation systems. That is complemented by performing topographic imaging at a few, to several, energies in each case. That provides a full topographic and spectrophotometric analysis. Foreign objects can then be detected, localized, discriminated, and classified, so that they may be dealt with by excision, and replacement with benign system elements. We analyze statistical and operational concerns leading to the design of three systems: The first operates at x-ray energies of 1 - 10 keV; it deals with defects in microelectronic integrated circuits. The second operates at x-ray energies of 10 - 30 keV; it deals with the defects in human tissue. The chemical specificity and image resolution of the system will allow identification, localization, and mensuration of tumors without the need of biopsy. The system which we concentrate this discussion on, the third, operates at x- ray energies of 30 - 70 keV; it deals with the presence in transportation systems of explosive devices, and contraband materials and objects in luggage and cargo. We present the analysis of the statistical features of the detection problem in these types of systems, discussing the operational constraints which limits system performance. After considering the multivariate, multisignature, approach to the problem, we discuss the tomographic and spectrophotometric approach to the problem which yields a better solution to the detection problem within the operational constraints.

  2. Collapsed lung (pneumothorax)

    MedlinePlus

    ... provider will listen to your breathing with a stethoscope. If you have a collapsed lung, there are ... rupture, chest x-ray Pneumothorax - chest x-ray Respiratory system Chest tube insertion - series Pneumothorax - series References ...

  3. A prototype percutaneous transhepatic cholangiography training simulator with real-time breathing motion.

    PubMed

    Villard, P F; Vidal, F P; Hunt, C; Bello, F; John, N W; Johnson, S; Gould, D A

    2009-11-01

    We present here a simulator for interventional radiology focusing on percutaneous transhepatic cholangiography (PTC). This procedure consists of inserting a needle into the biliary tree using fluoroscopy for guidance. The requirements of the simulator have been driven by a task analysis. The three main components have been identified: the respiration, the real-time X-ray display (fluoroscopy) and the haptic rendering (sense of touch). The framework for modelling the respiratory motion is based on kinematics laws and on the Chainmail algorithm. The fluoroscopic simulation is performed on the graphic card and makes use of the Beer-Lambert law to compute the X-ray attenuation. Finally, the haptic rendering is integrated to the virtual environment and takes into account the soft-tissue reaction force feedback and maintenance of the initial direction of the needle during the insertion. Five training scenarios have been created using patient-specific data. Each of these provides the user with variable breathing behaviour, fluoroscopic display tuneable to any device parameters and needle force feedback. A detailed task analysis has been used to design and build the PTC simulator described in this paper. The simulator includes real-time respiratory motion with two independent parameters (rib kinematics and diaphragm action), on-line fluoroscopy implemented on the Graphics Processing Unit and haptic feedback to feel the soft-tissue behaviour of the organs during the needle insertion.

  4. Development of Superconducting Insertion Device Magnets at NSRRC

    NASA Astrophysics Data System (ADS)

    Hwang, C. S.; Chang, C. H.; Chen, H. H.; Jan, J. C.; Lin, F. Y.; Fan, T. C.; Chen, J.; Hsu, S. N.; Hsu, K. T.; Huang, M. H.; Chang, H. P.; Hsiung, G. Y.; Chien, Y. C.; Chen, J. R.; Kuo, C. C.; Chen, C. T.

    2007-01-01

    A superconducting wavelength shifter (SWLS) with a magnetic field of 6.5 T in cryogen-free operation provides X-rays for high-resolution X-ray microscopy, EXAFS, and medical imaging beamlines. A 32-pole superconducting wiggler (SW) with a period of 6.1 cm and a magnetic field of 3.2 T in a liquid helium bath provides for three dedicated protein crystallography beamlines. Additionally, three 16-pole in-achromatic superconducting wigglers (IASW) with a period of 6.1 cm and a field strength of 3.1 T were constructed in-house and installed between the first and second bending magnets of a TBA arc section. Development of a prototype superconducting undulator (SU15) with a period of 15 mm and a field strength of 1.4 T is currently underway at National Synchrotron Radiation Research Center (MSRRC).

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Manohar, N; Cho, S; Reynoso, F

    Purpose: To make benchtop x-ray fluorescence computed tomography (XFCT) practical for routine preclinical imaging tasks with gold nanoparticles (GNPs) by deploying, integrating, and characterizing a dedicated high-performance x-ray source and addition of simultaneous micro-CT functionality. Methods: Considerable research effort is currently under way to develop a polychromatic benchtop cone-beam XFCT system capable of imaging GNPs by stimulation and detection of gold K-shell x-ray fluorescence (XRF) photons. Recently, an ad hoc high-power x-ray source was incorporated and used to image the biodistribution of GNPs within a mouse, postmortem. In the current work, a dedicated x-ray source system featuring a liquid-cooled tungsten-targetmore » x-ray tube (max 160 kVp, ∼3 kW power) was deployed. The source was operated at 125 kVp, 24 mA. The tube’s compact dimensions allowed greater flexibility for optimizing both the irradiation and detection geometries. Incident x-rays were shaped by a conical collimator and filtered by 2 mm of tin. A compact “OEM” cadmium-telluride x-ray detector was implemented for detecting XRF/scatter spectra. Additionally, a flat panel detector was installed to allow simultaneous transmission CT imaging. The performance of the system was characterized by determining the detection limit (10-second acquisition time) for inserts filled with water/GNPs at various concentrations (0 and 0.010–1.0 wt%) and embedded in a small-animal-sized phantom. The phantom was loaded with 0.5, 0.3, and 0.1 wt% inserts and imaged using XFCT and simultaneous micro-CT. Results: An unprecedented detection limit of 0.030 wt% was experimentally demonstrated, with a 33% reduction in acquisition time. The reconstructed XFCT image accurately localized the imaging inserts. Micro-CT imaging did not provide enough contrast to distinguish imaging inserts from the phantom under the current conditions. Conclusion: The system is immediately capable of in vivo preclinical XFCT imaging with GNPs. Micro-CT imaging will require optimization of irradiation parameters to improve contrast. Supported by NIH/NCI grant R01CA155446; This investigation was supported by NIH/NCI grant R01CA155446.« less

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tran, Ich C.; Tunuguntla, Ramya H.; Kim, Kyunghoon

    Carbon nanotube porins (CNTPs), small segments of carbon nanotubes capable of forming defined pores in lipid membranes, are important future components for bionanoelectronic devices as they could provide a robust analog of biological membrane channels. Furthermore, in order to control the incorporation of these CNT channels into lipid bilayers, it is important to understand the structure of the CNTPs before and after insertion into the lipid bilayer as well as the impact of such insertion on the bilayer structure. Here we employed a noninvasive in situ probe, small-angle X-ray scattering, to study the integration of CNT porins into dioleoylphosphatidylcholine bilayers.more » These results show that CNTPs in solution are stabilized by a monolayer of lipid molecules wrapped around their outer surface. We also demonstrate that insertion of CNTPs into the lipid bilayer results in decreased bilayer thickness with the magnitude of this effect increasing with the concentration of CNTPs.« less

  7. Identification of the lumbar interspinous spaces by palpation and verified by X-rays.

    PubMed

    Tanaka, Kei; Irikoma, Shingo; Kokubo, Sotaro

    2013-01-01

    Palpation has been shown to be rather inaccurate at identifying lumbar interspinous spaces in neuraxial anesthesia. The aim of this study is to assess the accuracy of the determination of the lumbar interspinous spaces by anesthesiologist's palpation using postoperative X-rays in obstetric patients. We reviewed the anesthetic record and the post-operative abdominal X-rays of the cesarean sections. We indwelled the epidural catheter for post-operative one-shot analgesia. We included combined spinal and epidural anesthesia cases and compared the interspinous level which the anesthesiologist recorded and the epidural catheter insertion level confirmed by abdominal X-ray for each case. We also evaluated the factors (age, body weight, height, Body Mass Index, gestational age, and the type of surgery [planned / emergency]) leading to misidentification of interspinous level. Nine hundred and sixty seven cesarean sections were performed and a total of 835 cases were evaluated. The levels of the puncture documented by the anesthesiologists were in agreement with the actual catheter insertion levels in 563 (67%) cases. When the anesthesiologists aimed at L2-3 level, we found the catheter insertion at L1-2 in 5 cases (4.9%), none of which had any post-operative neurological deficits. No variables evaluated were significantly associated with misidentification of interspinous level by the anesthesiologists. There was a discrepancy between the anesthesiologists' estimation by palpation and the actual catheter insertion level shown in X-rays. It seems to be safer to choose the interspinous level L3-4 or lower in spinal anesthesia. Copyright © 2013 Elsevier Editora Ltda. All rights reserved.

  8. Preventing bacterial growth on implanted device with an interfacial metallic film and penetrating X-rays.

    PubMed

    An, Jincui; Sun, An; Qiao, Yong; Zhang, Peipei; Su, Ming

    2015-02-01

    Device-related infections have been a big problem for a long time. This paper describes a new method to inhibit bacterial growth on implanted device with tissue-penetrating X-ray radiation, where a thin metallic film deposited on the device is used as a radio-sensitizing film for bacterial inhibition. At a given dose of X-ray, the bacterial viability decreases as the thickness of metal film (bismuth) increases. The bacterial viability decreases with X-ray dose increases. At X-ray dose of 2.5 Gy, 98% of bacteria on 10 nm thick bismuth film are killed; while it is only 25% of bacteria are killed on the bare petri dish. The same dose of X-ray kills 8% fibroblast cells that are within a short distance from bismuth film (4 mm). These results suggest that penetrating X-rays can kill bacteria on bismuth thin film deposited on surface of implant device efficiently.

  9. Two-axis sagittal focusing monochromator

    DOEpatents

    Haas, Edwin G; Stelmach, Christopher; Zhong, Zhong

    2014-05-13

    An x-ray focusing device and method for adjustably focusing x-rays in two orthogonal directions simultaneously. The device and method can be operated remotely using two pairs of orthogonal benders mounted on a rigid, open frame such that x-rays may pass through the opening in the frame. The added x-ray flux allows significantly higher brightness from the same x-ray source.

  10. A rotational and axial motion system load frame insert for in situ high energy x-ray studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shade, Paul A., E-mail: paul.shade.1@us.af.mil; Schuren, Jay C.; Turner, Todd J.

    2015-09-15

    High energy x-ray characterization methods hold great potential for gaining insight into the behavior of materials and providing comparison datasets for the validation and development of mesoscale modeling tools. A suite of techniques have been developed by the x-ray community for characterizing the 3D structure and micromechanical state of polycrystalline materials; however, combining these techniques with in situ mechanical testing under well characterized and controlled boundary conditions has been challenging due to experimental design requirements, which demand new high-precision hardware as well as access to high-energy x-ray beamlines. We describe the design and performance of a load frame insert withmore » a rotational and axial motion system that has been developed to meet these requirements. An example dataset from a deforming titanium alloy demonstrates the new capability.« less

  11. A simple method to accurately position Port-A-Cath without the aid of intraoperative fluoroscopy or other localizing devices.

    PubMed

    Horng, Huann-Cheng; Yuan, Chiou-Chung; Chao, Kuan-Chong; Cheng, Ming-Huei; Wang, Peng-Hui

    2007-06-01

    To evaluate the efficacy and acceptability of the Port-A-Cath (PAC) insertion method with (conventional group as II) and without (modified group as I) the aid of intraoperative fluoroscopy or other localizing devices. A total of 158 women with various kinds of gynecological cancers warranting PAC insertion (n = 86 in group I and n = 72 in group II, respectively) were evaluated. Data for analyses included patient age, main disease, dislocation site, surgical time, complications, and catheter outcome. There was no statistical difference between the two groups in terms of age, main disease, complications, and the experiencing of patent catheters. However, appropriate positioning (100% in group I, and 82% in group II) in the superior vena cava (SVC) showed statistical differences between the two groups (P = 0.001). In addition, the surgical time in group I was statistically shorter than that in group II (P < 0.001). The modified method for inserting the PAC offered the following benefits: including avoiding X-ray exposure for both the operator and the patient, defining the appropriate position in the SVC, and less surgical time. (c) 2007 Wiley-Liss, Inc.

  12. X-ray diffraction diagnostic design for the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Ahmed, Maryum F.; House, Allen; Smith, R. F.; Ayers, Jay; Lamb, Zachary S.; Swift, David W.

    2013-09-01

    This paper describes the design considerations for Target Diffraction In-Situ (TARDIS), an x-ray diffraction diagnostic at the National Ignition Facility. A crystal sample is ramp-compressed to peak pressures between 10 and 30 Mbar and, during a pressure hold period, is probed with quasi-monochromatic x-rays emanating from a backlighter source foil. The crystal spectrography diffraction lines are recorded onto image plates. The crystal sample, filter, and image plates are packaged into one assembly, allowing for accurate and repeatable target to image plate registration. Unconverted laser light impinges upon the device, generating debris, the effects of which have been mitigated. Dimpled blast shields, high strength steel alloy, and high-z tungsten are used to shield and protect the image plates. A tapered opening was designed to provide adequate thickness of shielding materials without blocking the drive beams or x-ray source from reaching the crystal target. The high strength steel unit serves as a mount for the crystal target and x-ray source foil. A tungsten body contains the imaging components. Inside this sub-assembly, there are three image plates: a 160 degree field of view curved plate directly opposite the target opening and two flat plates for the top and bottom. A polycarbonate frame, coated with the appropriate filter material and embedded with registration features for image plate location, is inserted into the diagnostic body. The target assembly is metrologized and then the diagnostic assembly is attached.

  13. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Non-image-intensified fluoroscopic x-ray system... fluoroscopic x-ray system. (a) Identification. A non-image-intensified fluoroscopic x-ray system is a device... of x-radiation into a visible image. This generic type of device may include signal analysis and...

  14. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Non-image-intensified fluoroscopic x-ray system... fluoroscopic x-ray system. (a) Identification. A non-image-intensified fluoroscopic x-ray system is a device... of x-radiation into a visible image. This generic type of device may include signal analysis and...

  15. Microanalysis of extended-test xenon hollow cathodes

    NASA Technical Reports Server (NTRS)

    Verhey, Timothy R.; Patterson, Michael J.

    1991-01-01

    Four hollow cathode electron sources were analyzed via boroscopy, scanning electron microscopy, energy dispersive x ray analysis, and x ray diffraction analysis. These techniques were used to develop a preliminary understanding of the chemistry of the devices that arise from contamination due to inadequate feed-system integrity and improper insert activation. Two hollow cathodes were operated in an ion thruster simulator at an emission current of 23.0 A for approximately 500 hrs. The two tests differed in propellant-feed systems, discharge power supplies, and activation procedures. Tungsten deposition and barium tungstate formation on the internal cathode surfaces occurred during the first test, which were believed to result from oxygen contamination of the propellant feed-system. Consequently, the test facility was upgraded to reduce contamination, and the test was repeated. The second hollow cathode was found to have experienced significantly less tungsten deposition. A second pair of cathodes examined were the discharge and the neutralizer hollow cathodes used in a life-test of a 30-cm ring-cusp ion thruster at a 5.5 kW power level. The cathodes' test history was documented and the post-test microanalyses are described. The most significant change resulting from the life-test was substantial tungsten deposition on the internal cathode surfaces, as well as removal of material from the insert surface. In addition, barium tungstate and molybdate were found on insert surfaces. As a result of the cathode examinations, procedures and approaches were proposed for improved discharge ignition and cathode longevity.

  16. 21 CFR 872.1800 - Extraoral source x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1800 Extraoral source x-ray system. (a... dental radiographic examination and diagnosis of diseases of the teeth, jaw, and oral structures. The x...

  17. 21 CFR 872.1800 - Extraoral source x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1800 Extraoral source x-ray system. (a... dental radiographic examination and diagnosis of diseases of the teeth, jaw, and oral structures. The x...

  18. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics

    PubMed Central

    Sowa, Katarzyna M.; Last, Arndt; Korecki, Paweł

    2017-01-01

    Polycapillary devices focus X-rays by means of multiple reflections of X-rays in arrays of bent glass capillaries. The size of the focal spot (typically 10–100 μm) limits the resolution of scanning, absorption and phase-contrast X-ray imaging using these devices. At the expense of a moderate resolution, polycapillary elements provide high intensity and are frequently used for X-ray micro-imaging with both synchrotrons and X-ray tubes. Recent studies have shown that the internal microstructure of such an optics can be used as a coded aperture that encodes high-resolution information about objects located inside the focal spot. However, further improvements to this variant of X-ray microscopy will require the challenging fabrication of tailored devices with a well-defined capillary microstructure. Here, we show that submicron coded aperture microscopy can be realized using a periodic grid that is placed at the output surface of a polycapillary optics. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics does not rely on the specific microstructure of the optics but rather takes advantage only of its focusing properties. Hence, submicron X-ray imaging can be realized with standard polycapillary devices and existing set-ups for micro X-ray fluorescence spectroscopy. PMID:28322316

  19. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics.

    PubMed

    Sowa, Katarzyna M; Last, Arndt; Korecki, Paweł

    2017-03-21

    Polycapillary devices focus X-rays by means of multiple reflections of X-rays in arrays of bent glass capillaries. The size of the focal spot (typically 10-100 μm) limits the resolution of scanning, absorption and phase-contrast X-ray imaging using these devices. At the expense of a moderate resolution, polycapillary elements provide high intensity and are frequently used for X-ray micro-imaging with both synchrotrons and X-ray tubes. Recent studies have shown that the internal microstructure of such an optics can be used as a coded aperture that encodes high-resolution information about objects located inside the focal spot. However, further improvements to this variant of X-ray microscopy will require the challenging fabrication of tailored devices with a well-defined capillary microstructure. Here, we show that submicron coded aperture microscopy can be realized using a periodic grid that is placed at the output surface of a polycapillary optics. Grid-enhanced X-ray coded aperture microscopy with polycapillary optics does not rely on the specific microstructure of the optics but rather takes advantage only of its focusing properties. Hence, submicron X-ray imaging can be realized with standard polycapillary devices and existing set-ups for micro X-ray fluorescence spectroscopy.

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

    NASA Astrophysics Data System (ADS)

    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. TIMING OF SHOCK WAVES

    DOEpatents

    Tuck, J.L.

    1955-03-01

    This patent relates to means for ascertaining the instant of arrival of a shock wave in an exploslve charge and apparatus utilizing this means to coordinate the timing of two operations involving a short lnterval of time. A pair of spaced electrodes are inserted along the line of an explosive train with a voltage applied there-across which is insufficient to cause discharge. When it is desired to initiate operation of a device at the time the explosive shock wave reaches a particular point on the explosive line, the device having an inherent time delay, the electrodes are located ahead of the point such that the ionization of the area between the electrodes caused by the traveling explosive shock wave sends a signal to initiate operation of the device to cause it to operate at the proper time. The operated device may be photographic equipment consisting of an x-ray illuminating tube.

  2. Modifications developed to improve x-ray detection devices

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Improvements in the development of x-ray detection devices are described. Emphasis is placed on lowering the temperature in order to achieve better x-ray response. A simplified charge integrator schematic is presented along with supporting tables. By using cryogenic operating temperatures, these x-ray detectors may eventually surpass the performance of the best semiconductor detectors.

  3. Accuracy of remote chest X-ray interpretation using Google Glass technology.

    PubMed

    Spaedy, Emily; Christakopoulos, Georgios E; Tarar, Muhammad Nauman J; Christopoulos, Georgios; Rangan, Bavana V; Roesle, Michele; Ochoa, Cristhiaan D; Yarbrough, William; Banerjee, Subhash; Brilakis, Emmanouil S

    2016-09-15

    We sought to explore the accuracy of remote chest X-ray reading using hands-free, wearable technology (Google Glass, Google, Mountain View, California). We compared interpretation of twelve chest X-rays with 23 major cardiopulmonary findings by faculty and fellows from cardiology, radiology, and pulmonary-critical care via: (1) viewing the chest X-ray image on the Google Glass screen; (2) viewing a photograph of the chest X-ray taken using Google Glass and interpreted on a mobile device; (3) viewing the original chest X-ray on a desktop computer screen. One point was given for identification of each correct finding and a subjective rating of user experience was recorded. Fifteen physicians (5 faculty and 10 fellows) participated. The average chest X-ray reading score (maximum 23 points) as viewed through the Google Glass, Google Glass photograph on a mobile device, and the original X-ray viewed on a desktop computer was 14.1±2.2, 18.5±1.5 and 21.3±1.7, respectively (p<0.0001 between Google Glass and mobile device, p<0.0001 between Google Glass and desktop computer and p=0.0004 between mobile device and desktop computer). Of 15 physicians, 11 (73.3%) felt confident in detecting findings using the photograph taken by Google Glass as viewed on a mobile device. Remote chest X-ray interpretation using hands-free, wearable technology (Google Glass) is less accurate than interpretation using a desktop computer or a mobile device, suggesting that further technical improvements are needed before widespread application of this novel technology. Published by Elsevier Ireland Ltd.

  4. Hard X-ray Sources for the Mexican Synchrotron Project

    NASA Astrophysics Data System (ADS)

    Reyes-Herrera, Juan

    2016-10-01

    One of the principal tasks for the design of the Mexican synchrotron was to define the storage ring energy. The main criteria for choosing the energy come from studying the electromagnetic spectrum that can be obtained from the synchrotron, because the energy range of the spectrum that can be obtained will determine the applications available to the users of the future light source. Since there is a public demand of hard X-rays for the experiments in the synchrotron community users from Mexico, in this work we studied the emission spectra from some hard X-ray sources which could be the best options for the parameters of the present Mexican synchrotron design. The calculations of the flux and the brightness for one Bending Magnet and four Insertion Devices are presented; specifically, for a Superconducting Bending Magnet (SBM), a Superconducting Wiggler (SCW), an In Vacuum Short Period Undulator (IV-SPU), a Superconducting Undulator (SCU) and for a Cryogenic Permanent Magnet Undulator (CPMU). Two commonly available synchrotron radiation programs were used for the computation (XOP and SRW). From the results, it can be concluded that the particle beam energy from the current design is enough to have one or more sources of hard X-rays. Furthermore, a wide range of hard X-ray region can be covered by the analyzed sources, and the choice of each type should be based on the specific characteristics of the X-ray beam to perform the experiments at the involved beamline. This work was done within the project Fomix Conacyt-Morelos ”Plan Estrategico para la construccion y operación de un Sincrotron en Morelos” (224392).

  5. Analysis of a Novel Diffractive Scanning Wire Beam Position Monitor (BPM) for Discriminative Profiling of Electron Vs. X Ray Beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tatchyn, Roman; /SLAC

    2011-09-01

    Recent numerical studies of Free Electron Lasers (FELs) operating in the Self Amplified Spontaneous Emission (SASE) regime indicate a large sensitivity of the gain to the degree of transverse overlap (and associated phase coherence) between the electron and photon beams traveling down the insertion device. Simulations of actual systems imply that accurate detection and correction for this relative loss of overlap, rather than correction for the absolute departure of the electron beam from a fixed axis, is the preferred function of an FEL amplifier's Beam Position Monitor (BPM) and corrector systems. In this note we propose a novel diffractive BPMmore » with the capability of simultaneously detecting and resolving the absolute (and relative) transverse positions and profiles of electron and x-ray beams co-propagating through an undulator. We derive the equations governing the performance of the BPM and examine its predicted performance for the SLAC Linac Coherent Light Source (LCLS), viz., for profiling multi-GeV electron bunches co-propagating with one-to-several-hundred keV x-ray beams. Selected research and development (r&d) tasks for fabricating and testing the proposed BPM are discussed.« less

  6. Pulse X-ray device for stereo imaging and few-projection tomography of explosive and fast processes

    NASA Astrophysics Data System (ADS)

    Palchikov, E. I.; Dolgikh, A. V.; Klypin, V. V.; Krasnikov, I. Y.; Ryabchun, A. M.

    2017-10-01

    This paper describes the operation principles and design features of the device for single pulse X-raying of explosive and high-speed processes, developed on the basis of a Tesla transformer with lumped secondary capacitor bank. The circuit with the lumped capacitor bank allows transferring a greater amount of energy to the discharge circuit as compared with the Marks-surge generator for more effective operation with remote X-ray tubes connected by coaxial cables. The device equipped with multiple X-ray tubes provides simultaneous X-raying of extended or spaced objects, stereo imaging, or few-projection tomography.

  7. X-Ray Scan Detection for Cargo Integrity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Valencia, Juan D.; Miller, Steven D.

    ABSTRACT The increase of terrorism and its global impact has made the determination of the contents of cargo containers a necessity. Existing technology allows non-intrusive inspections to determine the contents of a container rapidly and accurately. However, some cargo shipments are exempt from such inspections. Hence, there is a need for a technology that enables rapid and accurate means of detecting whether such containers were non-intrusively inspected. Non-intrusive inspections are most commonly performed utilizing high powered X-ray equipment. The challenge is creating a device that can detect short duration X-ray scans while maintaining a portable, battery powered, low cost, andmore » easy to use platform. The Pacific Northwest National Laboratory (PNNL) has developed a methodology and prototype device focused on this challenge. The prototype, developed by PNNL, is a battery powered electronic device that continuously measures its X-ray and Gamma exposure, calculates the dose equivalent rate, and makes a determination of whether the device has been exposed to the amount of radiation experienced during an X-ray inspection. Once an inspection is detected, the device will record a timestamp of the event and relay the information to authorized personnel via a visual alert, USB connection, and/or wireless communication. The results of this research demonstrate that PNNL’s prototype device can be effective at determining whether a container was scanned by X-ray equipment typically used for cargo container inspections. This paper focuses on laboratory measurements and test results acquired with the PNNL prototype device using several X-ray radiation levels. Keywords: Radiation, Scan, X-ray, Gamma, Detection, Cargo, Container, Wireless, RF« less

  8. Theoretical modeling of a portable x-ray tube based KXRF system to measure lead in bone

    PubMed Central

    Specht, Aaron J; Weisskopf, Marc G; Nie, Linda Huiling

    2017-01-01

    Objective K-shell x-ray fluorescence (KXRF) techniques have been used to identify health effects resulting from exposure to metals for decades, but the equipment is bulky and requires significant maintenance and licensing procedures. A portable x-ray fluorescence (XRF) device was developed to overcome these disadvantages, but introduced a measurement dependency on soft tissue thickness. With recent advances to detector technology, an XRF device utilizing the advantages of both systems should be feasible. Approach In this study, we used Monte Carlo simulations to test the feasibility of an XRF device with a high-energy x-ray tube and detector operable at room temperature. Main Results We first validated the use of Monte Carlo N-particle transport code (MCNP) for x-ray tube simulations, and found good agreement between experimental and simulated results. Then, we optimized x-ray tube settings and found the detection limit of the high-energy x-ray tube based XRF device for bone lead measurements to be 6.91 μg g−1 bone mineral using a cadmium zinc telluride detector. Significance In conclusion, this study validated the use of MCNP in simulations of x-ray tube physics and XRF applications, and demonstrated the feasibility of a high-energy x-ray tube based XRF for metal exposure assessment. PMID:28169835

  9. Theoretical modeling of a portable x-ray tube based KXRF system to measure lead in bone.

    PubMed

    Specht, Aaron J; Weisskopf, Marc G; Nie, Linda Huiling

    2017-03-01

    K-shell x-ray fluorescence (KXRF) techniques have been used to identify health effects resulting from exposure to metals for decades, but the equipment is bulky and requires significant maintenance and licensing procedures. A portable x-ray fluorescence (XRF) device was developed to overcome these disadvantages, but introduced a measurement dependency on soft tissue thickness. With recent advances to detector technology, an XRF device utilizing the advantages of both systems should be feasible. In this study, we used Monte Carlo simulations to test the feasibility of an XRF device with a high-energy x-ray tube and detector operable at room temperature. We first validated the use of Monte Carlo N-particle transport code (MCNP) for x-ray tube simulations, and found good agreement between experimental and simulated results. Then, we optimized x-ray tube settings and found the detection limit of the high-energy x-ray tube based XRF device for bone lead measurements to be 6.91 µg g -1 bone mineral using a cadmium zinc telluride detector. In conclusion, this study validated the use of MCNP in simulations of x-ray tube physics and XRF applications, and demonstrated the feasibility of a high-energy x-ray tube based XRF for metal exposure assessment.

  10. High Precision Grids for Neutron, Hard X-Ray, and Gamma-Ray Imaging Systems

    NASA Technical Reports Server (NTRS)

    Campbell, Jonathan W. (Inventor)

    2002-01-01

    Fourier telescopes permit observations over a very broad band of energy. They generally include synthetic spatial filtering structures, known as multilayer grids or grid pairs consisting of alternate layers of absorbing and transparent materials depending on whether neutrons or photons are being imaged. For hard x-rays and gamma rays high (absorbing) and low (transparent) atomic number elements, termed high-Z and low-Z materials may be used. Fabrication of these multilayer grid structures is not without its difficulties. Herein the alternate layers of the higher material and the lower material are inserted in a polyhedron, transparent to photons of interest, through an open face of the polyhedron. The inserted layers are then uniformly compressed to form a multilayer grid.

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Couprie, M. E.; Benabderrahmane, C.; Berteaud, P.

    The SOLEIL storage ring presents a very high fraction of its circumference dedicated to accommodate Insertion Devices (ID). Over the 25 presently planned insertion devices presenting a large variety of systems, 16 have been already installed and commissioned in September 2009. The UV-VUV region is covered with electromagnetic devices, offering tuneable polarisations. An electromagnet/permanent magnet undulator using copper sheets coils for fast switching of the helicity is under construction. 13 APPLE-II type undulators, with period ranging from 80 down to 36 mm, provide photons in the 0.1-10 keV region, some of them featuring tapering or quasi-periodicity. Five U20 in vacuummore » undulators cover typically the 3-30 keV range whereas an in vacuum wiggler, with compensation of the magnetic forces via adequate springs will cover the 10-50 keV spectral domain. R and D on cryogenic in-vacuum undulator is also under progress. A magnetic chicane using permanent magnet dipoles has also been designed in order to accommodate two canted undulators on the same straight section. A wiggler dedicated to slicing (production of femto second long pulses) is also being designed, its radiation will also serve for an X-ray beamline.« less

  12. Measurement of the effective energy of pulsed X-rays emitted from a Mather-type plasma focus device.

    PubMed

    Miremad, Seyed Milad; Shirani Bidabadi, Babak

    2017-07-01

    The current study examined the effective energy of pulsed x-rays emitted from a Mather-type plasma focus device with copper anodes at an energy range of 2-3kJ using x-ray transmission radiography. Aluminum filters of different thicknesses and dental x-ray film were used. When air gas was used at a constant voltage of 21kV at 0.3, 0.6, 0.9 and 1.2 mbar, the effective energy of pulsed the x-ray was 10.9, 10.7, 17.3 and 15.8keV, respectively. At 0.6 mbar of air, as the operating voltage increased to 19, 21 and 23kV, the effective energy of the x-ray radiation was 10.6, 10.7 and 12.4keV, respectively. Comprehensive investigation of the characteristics of x-ray emission from plasma focus devices makes it feasible to use this device as an intensive x-ray generator for medical and industrial purposes. The present study is a part of a program which is planned to realize these applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Selective Tuning of Gilbert Damping in Spin-Valve Trilayer by Insertion of Rare-Earth Nanolayers.

    PubMed

    Zhang, Wen; Zhang, Dong; Wong, Ping Kwan Johnny; Yuan, Honglei; Jiang, Sheng; van der Laan, Gerrit; Zhai, Ya; Lu, Zuhong

    2015-08-12

    Selective tuning of the Gilbert damping constant, α, in a NiFe/Cu/FeCo spin-valve trilayer has been achieved by inserting different rare-earth nanolayers adjacent to the ferromagnetic layers. Frequency dependent analysis of the ferromagnetic resonances shows that the initially small magnitude of α in the NiFe and FeCo layers is improved by Tb and Gd insertions to various amounts. Using the element-specific technique of X-ray magnetic circular dichroism, we find that the observed increase in α can be attributed primarily to the orbital moment enhancement of Ni and Co, rather than that of Fe. The amplitude of the enhancement depends on the specific rare-earth element, as well as on the lattice and electronic band structure of the transition metals. Our results demonstrate an effective way for individual control of the magnetization dynamics in the different layers of the spin-valve sandwich structures, which will be important for practical applications in high-frequency spintronic devices.

  14. Potentiality of a small and fast dense plasma focus as hard x-ray source for radiographic applications

    NASA Astrophysics Data System (ADS)

    Pavez, Cristian; Pedreros, José; Zambra, Marcelo; Veloso, Felipe; Moreno, José; Ariel, Tarifeño-Saldivia; Soto, Leopoldo

    2012-10-01

    Currently, a new generation of small plasma foci devices is being developed and researched, motivated by its potential use as portable sources of x-ray and neutron pulsed radiation for several applications. In this work, experimental results of the accumulated x-ray dose angular distribution and characterization of the x-ray source size are presented for a small and fast plasma focus device, ‘PF-400J’ (880 nF, 40 nH, 27-29 kV, ˜350 J, T/4 ˜ 300 ns). The experimental device is operated using hydrogen as the filling gas in a discharge region limited by a volume of around 80 cm3. The x-ray radiation is monitored, shot by shot, using a scintillator-photomultiplier system located outside the vacuum chamber at 2.3 m far away from the radiation emission region. The angular x-ray dose distribution measurement shows a well-defined emission cone, with an expansion angle of 5°, which is observed around the plasma focus device symmetry axis using TLD-100 crystals. The x-ray source size measurements are obtained using two image-forming aperture techniques: for both cases, one small (pinhole) and one large for the penumbral imaging. These results are in agreement with the drilling made by the energetic electron beam coming from the pinch region. Additionally, some examples of image radiographic applications are shown in order to highlight the real possibilities of the plasma focus device as a portable x-ray source. In the light of the obtained results and the scaling laws observed in plasma foci devices, we present a discussion on the potentiality and advantages of these devices as pulsed and safe sources of x-radiation for applications.

  15. Operando Grazing Incidence Small-Angle X-ray Scattering/X-ray Diffraction of Model Ordered Mesoporous Lithium-Ion Battery Anodes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bhaway, Sarang M.; Qiang, Zhe; Xia, Yanfeng

    Emergent lithium-ion (Li +) batteries commonly rely on nanostructuring of the active electrode materials to decrease the Li + ion diffusion path length and to accommodate the strains associated with the insertion and de-insertion of Li +, but in many cases these nanostructures evolve during electrochemical charging–discharging. This change in the nanostructure can adversely impact performance, and challenges remain regarding how to control these changes from the perspective of morphological design. In order to address these questions, operando grazing-incidence small-angle X-ray scattering and X-ray diffraction (GISAXS/GIXD) were used to assess the structural evolution of a family of model ordered mesoporousmore » NiCo 2O 4 anode films during battery operation. The pore dimensions were systematically varied and appear to impact the stability of the ordered nanostructure during the cycling. For the anodes with small mesopores (≈9 nm), the ordered nanostructure collapses during the first two charge–discharge cycles, as determined from GISAXS. This collapse is accompanied by irreversible Li-ion insertion within the oxide framework, determined from GIXD and irreversible capacity loss. Anodes with larger ordered mesopores (17–28 nm) mostly maintained their nanostructure through the first two cycles with reversible Li-ion insertion. During the second cycle, there was a small additional deformation of the mesostructure. Furthermore, this preservation of the ordered structure lead to significant improvement in capacity retention during these first two cycles; but, a gradual loss in the ordered nanostructure from continuing deformation of the ordered structure during additional charge–discharge cycles leads to capacity decay in battery performance. We translate these multiscale operando measurements provide insight into how changes at the atomic scale (lithium insertion and de-insertion) to the nanostructure during battery operation. Moreover, small changes in the nanostructure can build up to significant morphological transformations that adversely impact battery performance through multiple charge–discharge cycles.« less

  16. Operando Grazing Incidence Small-Angle X-ray Scattering/X-ray Diffraction of Model Ordered Mesoporous Lithium-Ion Battery Anodes

    DOE PAGES

    Bhaway, Sarang M.; Qiang, Zhe; Xia, Yanfeng; ...

    2017-02-07

    Emergent lithium-ion (Li +) batteries commonly rely on nanostructuring of the active electrode materials to decrease the Li + ion diffusion path length and to accommodate the strains associated with the insertion and de-insertion of Li +, but in many cases these nanostructures evolve during electrochemical charging–discharging. This change in the nanostructure can adversely impact performance, and challenges remain regarding how to control these changes from the perspective of morphological design. In order to address these questions, operando grazing-incidence small-angle X-ray scattering and X-ray diffraction (GISAXS/GIXD) were used to assess the structural evolution of a family of model ordered mesoporousmore » NiCo 2O 4 anode films during battery operation. The pore dimensions were systematically varied and appear to impact the stability of the ordered nanostructure during the cycling. For the anodes with small mesopores (≈9 nm), the ordered nanostructure collapses during the first two charge–discharge cycles, as determined from GISAXS. This collapse is accompanied by irreversible Li-ion insertion within the oxide framework, determined from GIXD and irreversible capacity loss. Anodes with larger ordered mesopores (17–28 nm) mostly maintained their nanostructure through the first two cycles with reversible Li-ion insertion. During the second cycle, there was a small additional deformation of the mesostructure. Furthermore, this preservation of the ordered structure lead to significant improvement in capacity retention during these first two cycles; but, a gradual loss in the ordered nanostructure from continuing deformation of the ordered structure during additional charge–discharge cycles leads to capacity decay in battery performance. We translate these multiscale operando measurements provide insight into how changes at the atomic scale (lithium insertion and de-insertion) to the nanostructure during battery operation. Moreover, small changes in the nanostructure can build up to significant morphological transformations that adversely impact battery performance through multiple charge–discharge cycles.« less

  17. Operando Grazing Incidence Small-Angle X-ray Scattering/X-ray Diffraction of Model Ordered Mesoporous Lithium-Ion Battery Anodes.

    PubMed

    Bhaway, Sarang M; Qiang, Zhe; Xia, Yanfeng; Xia, Xuhui; Lee, Byeongdu; Yager, Kevin G; Zhang, Lihua; Kisslinger, Kim; Chen, Yu-Ming; Liu, Kewei; Zhu, Yu; Vogt, Bryan D

    2017-02-28

    Emergent lithium-ion (Li + ) batteries commonly rely on nanostructuring of the active electrode materials to decrease the Li + ion diffusion path length and to accommodate the strains associated with the insertion and de-insertion of Li + , but in many cases these nanostructures evolve during electrochemical charging-discharging. This change in the nanostructure can adversely impact performance, and challenges remain regarding how to control these changes from the perspective of morphological design. In order to address these questions, operando grazing-incidence small-angle X-ray scattering and X-ray diffraction (GISAXS/GIXD) were used to assess the structural evolution of a family of model ordered mesoporous NiCo 2 O 4 anode films during battery operation. The pore dimensions were systematically varied and appear to impact the stability of the ordered nanostructure during the cycling. For the anodes with small mesopores (≈9 nm), the ordered nanostructure collapses during the first two charge-discharge cycles, as determined from GISAXS. This collapse is accompanied by irreversible Li-ion insertion within the oxide framework, determined from GIXD and irreversible capacity loss. Conversely, anodes with larger ordered mesopores (17-28 nm) mostly maintained their nanostructure through the first two cycles with reversible Li-ion insertion. During the second cycle, there was a small additional deformation of the mesostructure. This preservation of the ordered structure lead to significant improvement in capacity retention during these first two cycles; however, a gradual loss in the ordered nanostructure from continuing deformation of the ordered structure during additional charge-discharge cycles leads to capacity decay in battery performance. These multiscale operando measurements provide insight into how changes at the atomic scale (lithium insertion and de-insertion) are translated to the nanostructure during battery operation. Moreover, small changes in the nanostructure can build up to significant morphological transformations that adversely impact battery performance through multiple charge-discharge cycles.

  18. Advancing the Technology of Monolithic CMOS detectors for their use as X-ray Imaging Spectrometers

    NASA Astrophysics Data System (ADS)

    Kenter, Almus

    The Smithsonian Astrophysical Observatory (SAO) proposes a two year program to further advance the scientific capabilities of monolithic CMOS detectors for use as x-ray imaging spectrometers. This proposal will build upon the progress achieved with funding from a previous APRA proposal that ended in 2013. As part of that previous proposal, x- ray optimized, highly versatile, monolithic CMOS imaging detectors and technology were developed and tested. The performance and capabilities of these devices were then demonstrated, with an emphasis on the performance advantages these devices have over CCDs and other technologies. The developed SAO/SRI-Sarnoff CMOS devices incorporate: Low noise, high sensitivity ("gain") pixels; Highly parallel on-chip signal chains; Standard and very high resistivity (30,000Ohm-cm) Si; Back-Side thinning and passivation. SAO demonstrated the performance benefits of each of these features in these devices. This new proposal high-lights the performance of this previous generation of devices, and segues into new technology and capability. The high sensitivity ( 135uV/e) 6 Transistor (6T) Pinned Photo Diode (PPD) pixels provided a large charge to voltage conversion gain to the detect and resolve even small numbers of photo electrons produced by x-rays. The on-chip, parallel signal chain processed an entire row of pixels in the same time that a CCD requires to processes a single pixel. The resulting high speed operation ( 1000 times faster than CCD) provide temporal resolution while mitigating dark current and allowed room temperature operation. The high resistivity Si provided full (over) depletion for thicker devices which increased QE for higher energy x-rays. In this proposal, SAO will investigate existing NMOS and existing PMOS devices as xray imaging spectrometers. Conventional CMOS imagers are NMOS. NMOS devices collect and measure photo-electrons. In contrast, PMOS devices collect and measure photo-holes. PMOS devices have various attributes that would make them superior for use in X-ray astronomy. In particular, PMOS has: "no" photo-charge recombination; "no" Random Telegraph Signal noise (RTS); and lower read noise. The existing SRI/Sarnoff PMOS devices are small and have been developed for non-intensified night vision applications, however, no x-ray evaluation of a monolithic PMOS device has ever been made. In addition to these PMOS devices, SAO will also evaluate existing NMOS scale-able format devices that can be fabricated in any rectangular size/shape using stitchable reticles. These "Mk by Nk" devices would be ideal for large X-ray focal planes or long grating readouts. The Sarnoff/SRI Mk by Nk format devices have been designed, with foresight, so that they can be fabricated in either PMOS or NMOS by changing a single fabrication reticle and by changing the type of Si substrate. If X-ray performance results are expected, this proposal will lead the way to future fabrication of Mk by Nk PMOS devices that would be ideal for X-ray astronomy missions such as "X-ray Surveyor". SAO will also investigate the interaction of directly deposited Optical Blocking Filters (OBFs) on various back side passivated devices, and their resultant effects on very "soft" x-ray response. The latest CMOS processes and very fast on-chip, and off-chip digital readout signal chains and camera systems will be demonstrated.

  19. 42 CFR 411.351 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... professional and technical components of any diagnostic test or procedure using x-rays, ultrasound...-ray, fluoroscopy, or ultrasound procedures that require the insertion of a needle, catheter, tube, or...

  20. 42 CFR 411.351 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... professional and technical components of any diagnostic test or procedure using x-rays, ultrasound...-ray, fluoroscopy, or ultrasound procedures that require the insertion of a needle, catheter, tube, or...

  1. 42 CFR 411.351 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... professional and technical components of any diagnostic test or procedure using x-rays, ultrasound...-ray, fluoroscopy, or ultrasound procedures that require the insertion of a needle, catheter, tube, or...

  2. 77 FR 27461 - Draft Guidance for Industry and Food and Drug Administration Staff; Pediatric Information for X...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-10

    ...] Draft Guidance for Industry and Food and Drug Administration Staff; Pediatric Information for X-Ray... guidance entitled ``Pediatric Information for X-ray Imaging Device Premarket Notifications.'' This draft... premarket notifications for x-ray imaging devices with indications for use in pediatric populations. FDA...

  3. X-ray scan detection for cargo integrity

    NASA Astrophysics Data System (ADS)

    Valencia, Juan; Miller, Steve

    2011-04-01

    The increase of terrorism and its global impact has made the determination of the contents of cargo containers a necessity. Existing technology allows non-intrusive inspections to determine the contents of a container rapidly and accurately. However, some cargo shipments are exempt from such inspections. Hence, there is a need for a technology that enables rapid and accurate means of detecting whether such containers were non-intrusively inspected. Non-intrusive inspections are most commonly performed utilizing high powered X-ray equipment. The challenge is creating a device that can detect short duration X-ray scans while maintaining a portable, battery powered, low cost, and easy to use platform. The Pacific Northwest National Laboratory (PNNL) has developed a methodology and prototype device focused on this challenge. The prototype, developed by PNNL, is a battery powered electronic device that continuously measures its X-ray and Gamma exposure, calculates the dose equivalent rate, and makes a determination of whether the device has been exposed to the amount of radiation experienced during an X-ray inspection. Once an inspection is detected, the device will record a timestamp of the event and relay the information to authorized personnel via a visual alert, USB connection, and/or wireless communication. The results of this research demonstrate that PNNL's prototype device can be effective at determining whether a container was scanned by X-ray equipment typically used for cargo container inspections. This paper focuses on laboratory measurements and test results acquired with the PNNL prototype device using several X-ray radiation levels.

  4. Real-time image-guided nasogastric feeding tube placement: A case series using Kangaroo with IRIS Technology in an ICU.

    PubMed

    Mizzi, Anna; Cozzi, Silvano; Beretta, Luigi; Greco, Massimiliano; Braga, Marco

    2017-05-01

    Pulmonary misplacement during the blind insertion of enteral feeding tubes is frequent, particularly in ventilated and neurologically impaired patients. This is probably the first clinical study using the Kangaroo Feeding Tube with IRIS technology (IRIS) which incorporates a camera designed to provide anatomic landmark visualization during insertion. The study aim was to evaluate IRIS performance during bedside gastric placement. This is the first prospective study to collect data on the use of IRIS. Twenty consecutive unconscious patients requiring enteral nutrition were recruited at a single center. IRIS placement was considered complete when a clear image of the gastric mucosa appeared. Correct placement was confirmed using a contrast-enhanced abdominal X-ray. To evaluate the device performance over time, the camera was activated every other day up to 17 d postplacement. In 7 (35%) patients, the trachea was initially visualized, requiring a second placement attempt with the same tube. The IRIS camera allowed recognition of the gastric mucosa in 18 (90%) patients. The esophagogastric junction was identified in one patient, while in a second patient the quality of visualization was poor. Contrast-enhanced X-ray confirmed the gastric placement of IRIS in all patients. IRIS allowed identification of gastric mucosa in 14 (70%) patients 3 d after placement. Performance progressively declined with time (P = 0.006, chi-square for trend). IRIS placement could have spared X-ray confirmation in almost all patients and prevented misplacement into the airway in about one third. Visualization quality needs to be improved, particularly after the first week. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. 49 CFR Appendix A to Part 1511 - Aviation Security Infrastructure Fee

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... final acceptance testing. This includes such equipment as Metal Detection Devices, Hand Wands, X-ray... such equipment as Metal Detection Devices, Hand Wands, X-ray screening machines, Explosives Trace... as test objects and X-ray radiation surveys, electricity costs and maintenance contract costs...

  6. Diamond-anvil high-pressure cell with improved x-ray collimation system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schiferl, D.; Olinger, B.W.; Livingston, R.W.

    1986-07-22

    This patent describes a diamond-anvil high-pressure cell having a tubular piston and a cylinder in which the piston is slidable to effect compression of a pair of opposed diamonds located between the piston and the cylinder. The piston includes a central bore opening on one end, an adjustable X-ray collimation system comprising a tubular insert engageable in the bore of the piston, the insert including a central bore and having first and second ends, with the first end of the insert being closest to the opposed diamonds and the second end of the insert extending out of the open endmore » of the piston, a collimator insertable in the bore of the tubular insert. The collimator has a central bore and having first and second ends corresponding respectively with the first and second ends of the insert, elastomeric pivot means mounted in the bore of the insert at the first end of the insert for flexibly retaining the first end of the collimator while allowing the collimator to pivot within the pivot means, and adjustable locking means located at the second end of the insert for adjusting and securing the second end of the collimator so as to be in alignment with the opposed diamonds.« less

  7. 21 CFR 872.1810 - Intraoral source x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1810 Intraoral source x-ray system. (a... intended for dental radiographic examination and diagnosis of diseases of the teeth, jaw, and oral...

  8. Testing a Novel 3D Printed Radiographic Imaging Device for Use in Forensic Odontology.

    PubMed

    Newcomb, Tara L; Bruhn, Ann M; Giles, Bridget; Garcia, Hector M; Diawara, Norou

    2017-01-01

    There are specific challenges related to forensic dental radiology and difficulties in aligning X-ray equipment to teeth of interest. Researchers used 3D printing to create a new device, the combined holding and aiming device (CHAD), to address the positioning limitations of current dental X-ray devices. Participants (N = 24) used the CHAD, soft dental wax, and a modified external aiming device (MEAD) to determine device preference, radiographer's efficiency, and technique errors. Each participant exposed six X-rays per device for a total of 432 X-rays scored. A significant difference was found at the 0.05 level between the three devices (p = 0.0015), with the MEAD having the least amount of total errors and soft dental wax taking the least amount of time. Total errors were highest when participants used soft dental wax-both the MEAD and the CHAD performed best overall. Further research in forensic dental radiology and use of holding devices is needed. © 2016 American Academy of Forensic Sciences.

  9. Effectiveness of X-ray grating interferometry for non-destructive inspection of packaged devices

    NASA Astrophysics Data System (ADS)

    Uehara, Masato; Yashiro, Wataru; Momose, Atsushi

    2013-10-01

    It is difficult to inspect packaged devices such as IC packages and power modules because the devices contain various components, such as semiconductors, metals, ceramics, and resin. In this paper, we demonstrated the effectiveness of X-ray grating interferometry (XGI) using a laboratory X-ray tube for the industrial inspection of packaged devices. The obtained conventional absorption image showed heavy-elemental components such as metal wires and electrodes, but the image did not reveal the defects in the light-elemental components. On the other hand, the differential phase-contrast image obtained by XGI revealed microvoids and scars in the encapsulant of the samples. The visibility contrast image also obtained by XGI showed some cracks in the ceramic insulator of power module sample. In addition, the image showed the silicon plate surrounded by the encapsulant having the same X-ray absorption coefficient. While these defects and components are invisible in the conventional industrial X-ray imaging, XGI thus has an attractive potential for the industrial inspection of the packaged devices.

  10. Hard X-Rays can BE Used to Visualize Cochlear Soft Tissue Displacements in a Closed Cochlea

    NASA Astrophysics Data System (ADS)

    Richter, C.-P.; Fishman, A.; Fan, L.; Shintani, S.; Rau, C.

    2009-02-01

    Experiments were made at the Advanced Photon Source (APS), Argonne National Laboratory. The APS is a synchrotron radiation source of the third generation, for which the particular characteristic is the highly coherent X-ray radiation. X-rays are generated with an undulator, inserted in a straight section of the storage ring. Images taken with hard X-rays at full field. A video flow algorithm by Lucas and Kanade was used to determine and quantify cochlear soft tissue displacements. The results show that displacements as low as 100 nm could be visualized.

  11. 21 CFR Appendix B to Subpart B of... - Scope of Product Coverage

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Transducer ITX—Transducer, Ultrasonic, Diagnostic Diagnostic X-Ray Imaging Devices (except mammographic x-ray systems): RA 892.1600 Angiographic X-Ray System IZI—System, X-Ray, Angiographic RA 892.1650 Image-Intensified Fluoroscopic X-Ray System MQB—Solid State X-Ray Imager (Flat Panel/Digital Imager) JAA—System, X...

  12. 21 CFR Appendix B to Subpart B of... - Scope of Product Coverage

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Transducer ITX—Transducer, Ultrasonic, Diagnostic Diagnostic X-Ray Imaging Devices (except mammographic x-ray systems): RA 892.1600 Angiographic X-Ray System IZI—System, X-Ray, Angiographic RA 892.1650 Image-Intensified Fluoroscopic X-Ray System MQB—Solid State X-Ray Imager (Flat Panel/Digital Imager) JAA—System, X...

  13. 21 CFR 872.1850 - Lead-lined position indicator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Diagnostic Devices § 872.1850 Lead-lined position indicator. (a... dental x-ray tube and intended to aid in positioning the tube, to prevent the misfocusing of the x-rays...

  14. Integrated sensor biopsy device for real time tissue metabolism analysis

    NASA Astrophysics Data System (ADS)

    Delgado Alonso, Jesus; Lieberman, Robert A.; DiCarmine, Paul M.; Berry, David; Guzman, Narciso; Marpu, Sreekar B.

    2018-02-01

    Current methods for guiding cancer biopsies rely almost exclusively on images derived from X-ray, ultrasound, or magnetic resonance, which essentially characterize suspected lesions based only on tissue density. This paper presents a sensor integrated biopsy device for in situ tissue analysis that will enable biopsy teams to measure local tissue chemistry in real time during biopsy procedures, adding a valuable new set of parameters to augment and extend conventional image guidance. A first demonstrator integrating three chemical and biochemical sensors was tested in a mice strain that is a spontaneous breast cancer model. In all cases, the multisensory probe was able to discriminate between healthy tissue, the edge of the tumor, and total insertion inside the cancer tissue, recording real-time information about tissue metabolism.

  15. High resolution biomedical imaging system with direct detection of x-rays via a charge coupled device

    DOEpatents

    Atac, M.; McKay, T.A.

    1998-04-21

    An imaging system is provided for direct detection of x-rays from an irradiated biological tissue. The imaging system includes an energy source for emitting x-rays toward the biological tissue and a charge coupled device (CCD) located immediately adjacent the biological tissue and arranged transverse to the direction of irradiation along which the x-rays travel. The CCD directly receives and detects the x-rays after passing through the biological tissue. The CCD is divided into a matrix of cells, each of which individually stores a count of x-rays directly detected by the cell. The imaging system further includes a pattern generator electrically coupled to the CCD for reading a count from each cell. A display device is provided for displaying an image representative of the count read by the pattern generator from the cells of the CCD. 13 figs.

  16. High resolution biomedical imaging system with direct detection of x-rays via a charge coupled device

    DOEpatents

    Atac, Muzaffer; McKay, Timothy A.

    1998-01-01

    An imaging system is provided for direct detection of x-rays from an irradiated biological tissue. The imaging system includes an energy source for emitting x-rays toward the biological tissue and a charge coupled device (CCD) located immediately adjacent the biological tissue and arranged transverse to the direction of irradiation along which the x-rays travel. The CCD directly receives and detects the x-rays after passing through the biological tissue. The CCD is divided into a matrix of cells, each of which individually stores a count of x-rays directly detected by the cell. The imaging system further includes a pattern generator electrically coupled to the CCD for reading a count from each cell. A display device is provided for displaying an image representative of the count read by the pattern generator from the cells of the CCD.

  17. NOTE: An innovative phantom for quantitative and qualitative investigation of advanced x-ray imaging technologies

    NASA Astrophysics Data System (ADS)

    Chiarot, C. B.; Siewerdsen, J. H.; Haycocks, T.; Moseley, D. J.; Jaffray, D. A.

    2005-11-01

    Development, characterization, and quality assurance of advanced x-ray imaging technologies require phantoms that are quantitative and well suited to such modalities. This note reports on the design, construction, and use of an innovative phantom developed for advanced imaging technologies (e.g., multi-detector CT and the numerous applications of flat-panel detectors in dual-energy imaging, tomosynthesis, and cone-beam CT) in diagnostic and image-guided procedures. The design addresses shortcomings of existing phantoms by incorporating criteria satisfied by no other single phantom: (1) inserts are fully 3D—spherically symmetric rather than cylindrical; (2) modules are quantitative, presenting objects of known size and contrast for quality assurance and image quality investigation; (3) features are incorporated in ideal and semi-realistic (anthropomorphic) contexts; and (4) the phantom allows devices to be inserted and manipulated in an accessible module (right lung). The phantom consists of five primary modules: (1) head, featuring contrast-detail spheres approximate to brain lesions; (2) left lung, featuring contrast-detail spheres approximate to lung modules; (3) right lung, an accessible hull in which devices may be placed and manipulated; (4) liver, featuring conrast-detail spheres approximate to metastases; and (5) abdomen/pelvis, featuring simulated kidneys, colon, rectum, bladder, and prostate. The phantom represents a two-fold evolution in design philosophy—from 2D (cylindrically symmetric) to fully 3D, and from exclusively qualitative or quantitative to a design accommodating quantitative study within an anatomical context. It has proven a valuable tool in investigations throughout our institution, including low-dose CT, dual-energy radiography, and cone-beam CT for image-guided radiation therapy and surgery.

  18. The Latest Status of NSLS-II Insertion Devices

    NASA Astrophysics Data System (ADS)

    Tanabe, Toshi; Kitegi, Charles; He, Ping; Musardo, Marco; Rank, Oleg Chubar James; Cappadoro, Peter; Fernandes, Huston; Harder, David; Corwin, Todd

    2014-03-01

    The National Synchrotron Light Source-II (NSLS-II) project is now in the final stage of construction. The Linac, the Booster synchrotron, and the Storage Ring magnets girder assemblies have been installed. The first damping wiggler has been delivered and its field characteristics are carefully measured. A Three Pole Wiggler (3PW) and Apple-II type elliptically polarizing undulators (EPUs) have been fabricated by the vendors. Two 3.0m long in-vacuum undulators (IVUs) and one 1.5m long IVU are almost complete and waiting for factory acceptance tests. One 3.0m long IVU for Inelastic X-ray Scattering beamline is in fabrication by a different vendor. Recently two 2.8m long IVUs for long straight sections (LSSs) have been added to the project for "future beamlines". In addition, two 1.5m long IVUs and one 2.8m long IVU for LSSs have been procured for Advanced Beamlines for Biological Investigations with X-rays (ABBIX) project funded by National Institure of Health (NIH). Further, two 3.5m long EPUs for LSSs are being designed for NSLS-II Experimental Tools (NEXT) -Major Item of Equipment (MIE) project. To succeed these conventional IVUs, PrFeB based cryo-permanent magnet undulator (CPMU) is considered as next generation device of hard X-ray sources. An In-Vacuum Magnetic Measurement System (IVMMS) for cold in-situ Hall probe mapping of CPMUs up to 1.5m in length has been developed. Summary of the current status of each project and future plans for the NSLS-II ring will be discussed.

  19. Local structure and structural rigidity of the green phosphor β-SiAlON:Eu{sup 2+}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brgoch, J., E-mail: jbrgoch@uh.edu; Gaultois, M. W., E-mail: mgaultois@mrl.ucsb.edu; Seshadri, R.

    Eu{sup 2+} inserted in β-Si{sub 3−x}Al{sub x}O{sub x}N{sub 4−x} is a material that shows exceptional promise as a green-emitting phosphor. Synchrotron X-ray and neutron scattering, in conjunction with first-principles calculations and Eu L{sub 3} X-ray absorption measurements, yield a consistent picture of the composition, and the favorable position for Eu{sup 2+} substitution in the crystal structure. The Debye temperature Θ{sub D}, which is a proxy for structural rigidity relating to effectiveness as a phosphor, is very high for the starting β-Si{sub 3}N{sub 4} framework and is determined to decrease only slightly for the small amounts of Al{sup 3+} and O{supmore » 2−} co-substitution that are required for charge balance associated with Eu{sup 2+} insertion.« less

  20. Evaluation of Exposure From a Low Energy X-Ray Device Using Thermoluminescent Dosimeters

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Harris, William S., Jr.

    1997-01-01

    The exposure from an electron beam welding device was evaluated using thermoluminescent dosimeters (TLDs). The device generated low energy X-rays which the current dose equivalent conversion algorithm was not designed to evaluate making it necessary to obtain additional information relating to TLD operation at the photon energies encountered with the device. This was accomplished by performing irradiations at the National Institute of Standards and Technology (NIST) using low energy X-ray techniques. The resulting data was used to determine TLD badge response for low energy X-rays and to establish the relationship between TLD element response and the dose equivalent at specific depths in tissue for these photon energies. The new energy/dose equivalent calibration data was used to calculate the shallow and eye dose equivalent of badges exposed to the device.

  1. Software for X-Ray Images Calculation of Hydrogen Compression Device in Megabar Pressure Range

    NASA Astrophysics Data System (ADS)

    Egorov, Nikolay; Bykov, Alexander; Pavlov, Valery

    2007-06-01

    Software for x-ray images simulation is described. The software is a part of x-ray method used for investigation of an equation of state of hydrogen in a megabar pressure range. A graphical interface that clearly and simply allows users to input data for x-ray image calculation: properties of the studied device, parameters of the x-ray radiation source, parameters of the x-ray radiation recorder, the experiment geometry; to represent the calculation results and efficiently transmit them to other software for processing. The calculation time is minimized. This makes it possible to perform calculations in a dialogue regime. The software is written in ``MATLAB'' system.

  2. Spatially resolved high-resolution x-ray spectroscopy of high-current plasma-focus discharges.

    PubMed

    Zając, S; Rzadkiewicz, J; Rosmej, O; Scholz, M; Yongtao, Zhao; Gójska, A; Paduch, M; Zielińska, E

    2010-10-01

    Soft x-ray emission from a Mather-type plasma-focus device (PF-1000) operated at ∼400 kJ was measured. The high density and temperature plasma were generated by the discharge in the deuterium-argon gas mixture in the modified (high-current) plasma-focus configuration. A spherically bent mica crystal spectrograph viewing the axial output of the pinch region was used to measure the x-ray spectra. Spatially resolved spectra including the characteristic x-ray lines of highly ionized Ar and continua were recorded by means of an x-ray film. The x-ray emission of PF-1000 device was studied at different areas of the pinch.

  3. Spatially resolved high-resolution x-ray spectroscopy of high-current plasma-focus discharges

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    ZajaPc, S.; Rzadkiewicz, J.; Scholz, M.

    Soft x-ray emission from a Mather-type plasma-focus device (PF-1000) operated at {approx}400 kJ was measured. The high density and temperature plasma were generated by the discharge in the deuterium-argon gas mixture in the modified (high-current) plasma-focus configuration. A spherically bent mica crystal spectrograph viewing the axial output of the pinch region was used to measure the x-ray spectra. Spatially resolved spectra including the characteristic x-ray lines of highly ionized Ar and continua were recorded by means of an x-ray film. The x-ray emission of PF-1000 device was studied at different areas of the pinch.

  4. Effect of footwear and orthotic devices on stress reduction and soft tissue strain of the neuropathic foot.

    PubMed

    Lott, Donovan J; Hastings, Mary K; Commean, Paul K; Smith, Kirk E; Mueller, Michael J

    2007-03-01

    Ground reaction forces from walking result in stress (pressure) and soft tissue strain at the plantar aspect of the foot. Excessive plantar pressure and tissue strain on the insensate foot may lead to ulceration. Our study investigated the effect of therapeutic footwear and custom-made orthotic inserts on pressure and tissue strain along the second ray of the plantar foot, and how these two variables are associated. Twenty subjects (mean age 57.3 [SD 9.3] years, 12 male, 8 female, body mass index 32.5 [SD 7.4] kg/m2) with diabetes mellitus, peripheral neuropathy, and a history of a plantar ulcer participated. Plantar pressure data were recorded during computed tomography scans for four conditions (barefoot, shoe, shoe+total contact insert, and shoe+total contact insert+metatarsal pad). For each condition tested, tissue strain and plantar pressure were determined at the second metatarsal head and at 15 other points along the second ray. Differences were noted between the 4 conditions for pressure (P<0.004) and soft tissue strain (P<0.042) at the second metatarsal head. Correlation coefficients demonstrated an association between pressure and strain (Barefoot r=0.81, Shoe r=0.75, Shoe+total contact insert r=0.73, and Shoe+total contact insert+metatarsal pad r=0.44). Footwear and orthotic devices tested in this study decreased pressure and soft tissue strain at the second ray of the foot, and these two variables were strongly related. A better understanding of the role tissue strain plays in distributing plantar forces may lead to improvements in the design of orthotic devices.

  5. Effect of Footwear and Orthotic Devices on Stress Reduction and Soft Tissue Strain of the Neuropathic Foot

    PubMed Central

    Lott, Donovan J.; Hastings, Mary K.; Commean, Paul K.; Smith, Kirk E.; Mueller, Michael J.

    2007-01-01

    Background Ground reaction forces from walking result in stress (pressure) and soft tissue strain at the plantar aspect of the foot. Excessive plantar pressure and tissue strain on the insensate foot may lead to ulceration. Our study investigated the effect of therapeutic footwear and custom-made orthotic inserts on pressure and tissue strain along the second ray of the plantar foot, and how these two variables are associated. Methods Twenty subjects (mean age 57.3 [SD 9.3], 12 male, 8 female, body mass index 32.5 [SD 7.4]) with diabetes mellitus, peripheral neuropathy, and a history of a plantar ulcer participated. Plantar pressure data were recorded during computed tomography scans for four conditions (barefoot, shoe, shoe+total contact insert, and shoe+total contact insert+metatarsal pad). For each condition tested, tissue strain and plantar pressure were determined at the second metatarsal head and at 15 other points along the second ray. Findings Differences were noted between the 4 conditions for pressure (p < 0.004) and soft tissue strain (p < 0.042) at the second metatarsal head. Correlation coefficients demonstrated an association between pressure and strain (Barefoot r = 0.81, Shoe r = 0.75, Shoe+total contact insert r = 0.73, and Shoe+total contact insert+metatarsal pad r = 0.44). Intepretation Footwear and orthotic devices tested in this study decreased pressure and soft tissue strain at the second ray of the foot, and these two variables were strongly related. A better understanding of the role tissue strain plays in distributing plantar forces may lead to improvements in the design of orthotic devices. PMID:17182156

  6. FinEstBeaMS - A wide-range Finnish-Estonian Beamline for Materials Science at the 1.5 GeV storage ring at the MAX IV Laboratory

    NASA Astrophysics Data System (ADS)

    Pärna, R.; Sankari, R.; Kukk, E.; Nõmmiste, E.; Valden, M.; Lastusaari, M.; Kooser, K.; Kokko, K.; Hirsimäki, M.; Urpelainen, S.; Turunen, P.; Kivimäki, A.; Pankratov, V.; Reisberg, L.; Hennies, F.; Tarawneh, H.; Nyholm, R.; Huttula, M.

    2017-07-01

    The FinEstBeaMS beamline is under construction at the 1.5 GeV storage ring of the MAX IV Laboratory at Lund, Sweden. It has been designed to cover an unusually wide energy range from ultraviolet (4.3 eV) to soft X-rays (1000 eV) but experiments will also be possible at the Mg and Al Kα energies. Instead of having two different insertion devices and optical schemes for low and high photon energy regions, we have based our design on a single long-period, elliptically polarizing undulator and a plane grating monochromator. This solution will provide very good conditions for planned experiments in the whole photon energy region. The beamline will have two branches: one will mainly be used to investigate free atoms, molecules and clusters with photoelectron/photoion coincidence spectroscopy as well as solids with photoluminescence spectroscopy whereas the other one will be dedicated to ultra-high vacuum studies of surfaces and interfaces, utilizing X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. This paper focuses on the optical design of the beamline and general design concepts of the gas phase and solid state end stations.

  7. X-ray emission from high temperature plasmas

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1976-01-01

    The physical processes occurring in plasma focus devices were studied. These devices produce dense high temperature plasmas, which emit X rays of hundreds of KeV energy and one to ten billion neutrons per pulse. The processes in the devices seem related to solar flare phenomena, and would also be of interest for controlled thermonuclear fusion applications. The high intensity, short duration bursts of X rays and neutrons could also possibly be used for pumping nuclear lasers.

  8. Justification and good practice in using handheld portable dental X-ray equipment: a position paper prepared by the European Academy of DentoMaxilloFacial Radiology (EADMFR)

    PubMed Central

    Suomalainen, A; Brüllmann, D; Jacobs, R; Horner, K; Stamatakis, H C

    2015-01-01

    Handheld portable X-ray devices are increasingly used for intraoral radiography. This development introduces new challenges to staff and patient safety, for which new or revised risk assessments must be made and acted upon prior to use. Major issues might be: difficulties in using rectangular collimation with beam aiming devices, more complex matching of exposure settings to the X-ray receptor used (e.g. longer exposure times), movements owing to the units' weight, protection of the operator and third persons, and the use in uncontrolled environments. These problems may result in violation of the “as low as reasonably achievable’’, that is, ALARA principle by an increase in (re)exposures compared with the other available intraoral X-ray devices. Hence, the use of handheld portable X-ray devices should be considered only after careful and documented evaluation (which might be performed based on medical physics support), when there is evidence that handheld operation has benefits over traditional modalities and when no new risks to the operators and/or third parties are caused. It is expected that the use of handheld portable X-ray devices will be very exceptional, and for justified situations only. Special attention should be drawn to beam-aiming devices, rectangular collimation, the section of the X-ray receptor, focus–skin distance, and backscatter shielding, and that the unit delivers reproducible dose over the full set of environmental conditions (e.g. battery status and temperature). PMID:25710118

  9. Fabrication of 0.25-um electrode width SAW filters using x-ray lithography with a laser plasma source

    NASA Astrophysics Data System (ADS)

    Bobkowski, Romuald; Li, Yunlei; Fedosejevs, Robert; Broughton, James N.

    1996-05-01

    A process for the fabrication of surface acoustic wave (SAW) devices with line widths of 250 nm and less, based on x-ray lithography using a laser-plasma source has been developed. The x-ray lithography process is based on keV x-ray emission from Cu plasma produced by 15 Hz, 50 ps, 248 nm KrF excimer laser pulses. The full structure of a 2 GHz surface acoustic wave filter with interdigital transducers in a split-electrode geometry has been manufactured. The devices require patterning a 150 nm thick aluminum layer on a LiNbO3 substrate with electrodes 250 nm wide. The manufacturing process has two main steps: x-ray mask fabrication employing e-beam lithography and x-ray lithography to obtain the final device. The x-ray masks are fabricated on 1 micrometers thick membranes of Si2N4. The line patterns on the masks are written into PMMA resist using a scanning electron microscope which has been interfaced to a personal computer equipped to control the x and y scan voltages. The opaque regions of the x-ray mask are then formed by electroplating fine grain gold into the open spaces in the etched PMMA. The mask and sample are mounted in an exposure cassette with a fixed spacer of 10 micrometers separating them. The sample consists of a LiNbO3 substrate coated with Shipley XP90104C x-ray resist which has been previously characterized. The x-ray patterning is carried out in an exposure chamber with flowing helium background gas in order to minimize debris deposition on the filters. After etching the x-ray resist, the final patterns are produced using metallization and a standard lift-off technique. The SAW filters are then bonded and packaged onto impedance matching striplines. The resultant devices are tested using Scalar Network Analyzers. The final devices produced had a center frequency of 1.93 GHz with a bandwidth of 98 MHz, close to the expected performance of our simple design.

  10. Direct measurement of clinical mammographic x-ray spectra using a CdTe spectrometer.

    PubMed

    Santos, Josilene C; Tomal, Alessandra; Furquim, Tânia A; Fausto, Agnes M F; Nogueira, Maria S; Costa, Paulo R

    2017-07-01

    To introduce and evaluate a method developed for the direct measurement of mammographic x-ray spectra using a CdTe spectrometer. The assembly of a positioning system and the design of a simple and customized alignment device for this application is described. A positioning system was developed to easily and accurately locate the CdTe detector in the x-ray beam. Additionally, an alignment device to line up the detector with the central axis of the radiation beam was designed. Direct x-ray spectra measurements were performed in two different clinical mammography units and the measured x-ray spectra were compared with computer-generated spectra. In addition, the spectrometer misalignment effect was evaluated by comparing the measured spectra when this device is aligned relatively to when it is misaligned. The positioning and alignment of the spectrometer have allowed the measurements of direct mammographic x-ray spectra in agreement with computer-generated spectra. The most accurate x-ray spectral shape, related with the minimal HVL value, and high photon fluence for measured spectra was found with the spectrometer aligned according to the proposed method. The HVL values derived from both simulated and measured x-ray spectra differ at most 1.3 and 4.5% for two mammography devices evaluated in this study. The experimental method developed in this work allows simple positioning and alignment of a spectrometer for x-ray spectra measurements given the geometrical constraints and maintenance of the original configurations of mammography machines. © 2017 American Association of Physicists in Medicine.

  11. Kilopixel X-Ray Microcalorimeter Arrays for Astrophysics: Device Performance and Uniformity

    NASA Technical Reports Server (NTRS)

    Eckart, M. E.; Adams, J. S.; Bailey, C. N.; Bandler, S. R.; Chervenak, F. M.

    2011-01-01

    We are developing kilo-pixel arrays of TES microcalorimeters to enable high-resolution X-ray imaging spectrometers for future X-ray observatories and laboratory astrophysics experiments. Our current array design was targeted as a prototype for the X-ray Microcalorimeter Spectrometer proposed for the International X-ray Observatory, which calls for a 40x40-pixel core array of 300 micron devices with 2.5 e V energy resolution (at 6 keV). Here we present device characterization of our 32x32 arrays, including X-ray spectral performance of individual pixels within the array. We present our results in light of the understanding that our Mo/Au TESs act as weak superconducting links, causing the TES critical current (Ic) and transition shape to oscillate with applied magnetic field (B). We show Ic(B) measurements and discuss the uniformity of these measurements across the array, as well as implications regarding the uniformity of device noise and response. In addition, we are working to reduce pixel-to-pixel electrical and thermal crosstalk; we present recent test results from an array that has microstrip wiring and an angle-evaporated Cu backside heatsinking layer, which provides Cu coverage on the four sidewalls of the silicon wells beneath each pixel.

  12. X-Ray Detector for 1 to 30 keV

    NASA Technical Reports Server (NTRS)

    Alcorn, G.; Jackson, J., Jr; Grant, P.; Marshall, F.

    1983-01-01

    Array of silicon X-ray detecting diodes measures photon energy and provides image of X-ray pattern. Regardless of thickness of new X-ray detector, depletion region extends through it. Impinging X-rays generate electrons in quantities proportional to X-ray energy. X-ray detector is mated to chargecoupled-device array for image generation and processing. Useful in industrial part inspection, pulsed-plasma research and medical application.

  13. Blood Irradiator Interactive Tool Beta Version

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Howington, John; Potter, Charles; DeGroff, Tavias

    The “Blood Irradiator Interactive Tool” compares a typical Cs-137 Blood Irradiator with that of the capabilities of an average X-ray Irradiator. It is designed to inform the user about the potential capabilities that an average X-ray Irradiator could offer them. Specifically the tool compares the amount of blood bags that can be irradiated by the users’ machine with that of the average X-ray capability. It also forcasts the amount of blood that can be irradiated on yearly basis for both the users’ machine and an average X-ray Device. The Average X-ray capabilities are taken from the three X-ray devices currentlymore » on the market: The RS 3400 Rad Source X-ray Blood Irradiator and both the 2.0L and 3.5 L versions of the Best Theratronis Raycell MK2« less

  14. Local structure and structural rigidity of the green phosphor β -SiAlON:Eu 2+

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brgoch, J.; Gaultois, M. W.; Balasubramanian, M.

    Eu2+ inserted in beta-Si3-xAlxOxN4-x is a material that shows exceptional promise as a green-emitting phosphor. Synchrotron X-ray and neutron scattering, in conjunction with first-principles calculations and Eu L-3 X-ray absorption measurements, yield a consistent picture of the composition, and the favorable position for Eu2+ substitution in the crystal structure. The Debye temperature Theta(D), which is a proxy for structural rigidity relating to effectiveness as a phosphor, is very high for the starting beta-Si3N4 framework and is determined to decrease only slightly for the small amounts of Al3+ and O2- co-substitution that are required for charge balance associated with Eu2+ insertion.more » (C) 2014 AIP Publishing LLC.« less

  15. A haptic device for guide wire in interventional radiology procedures.

    PubMed

    Moix, Thomas; Ilic, Dejan; Bleuler, Hannes; Zoethout, Jurjen

    2006-01-01

    Interventional Radiology (IR) is a minimally invasive procedure where thin tubular instruments, guide wires and catheters, are steered through the patient's vascular system under X-ray imaging. In order to perform these procedures, a radiologist has to be trained to master hand-eye coordination, instrument manipulation and procedure protocols. The existing simulation systems all have major drawbacks: the use of modified instruments, unrealistic insertion lengths, high inertia of the haptic device that creates a noticeably degraded dynamic behavior or excessive friction that is not properly compensated for. In this paper we propose a quality training environment dedicated to IR. The system is composed of a virtual reality (VR) simulation of the patient's anatomy linked to a robotic interface providing haptic force feedback. This paper focuses on the requirements, design and prototyping of a specific haptic interface for guide wires.

  16. High spatial resolution X-ray and gamma ray imaging system using diffraction crystals

    DOEpatents

    Smither, Robert K [Hinsdale, IL

    2011-05-17

    A method and a device for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation are provided. The device comprises a plurality of arrays, with each array comprising a plurality of elements comprising a first collimator, a diffracting crystal, a second collimator, and a detector.

  17. X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility.

    PubMed

    Fournier, K B; Brown, C G; Yeoman, M F; Fisher, J H; Seiler, S W; Hinshelwood, D; Compton, S; Holdener, F R; Kemp, G E; Newlander, C D; Gilliam, R P; Froula, N; Lilly, M; Davis, J F; Lerch, Maj A; Blue, B E

    2016-11-01

    Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the National Ignition Facility's diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built-in calorimeters give in situ measurements of the x-ray environment along the sample lines of sight. The measured accuracy of sample responses as well as planned modifications to the XTRRA cassette is discussed.

  18. Advancing the technology of monolithic CMOS detectors for use as x-ray imaging spectrometers

    NASA Astrophysics Data System (ADS)

    Kenter, Almus; Kraft, Ralph; Gauron, Thomas; Amato, Stephen

    2017-08-01

    The Smithsonian Astrophysical Observatory (SAO) in collaboration with SRI/Sarnoff has been engaged in a multi year effort to advance the technology of monolithic back-thinned CMOS detectors for use as X-ray imaging spectrometers. The long term goal of this campaign is to produce X-ray Active Pixel Sensor (APS) detectors with Fano limited performance over the 0.1-10keV band while incorporating the many benefits of CMOS technology. These benefits include: low power consumption, radiation "hardness", high levels of integration, and very high read rates. Such devices would be ideal for candidate post 2020 decadal missions such as LYNX and for smaller more immediate applications such as CubeX. Devices from a recent fabrication have been back-thinned, packaged and tested for soft X-ray response. These devices have 16μm pitch, 6 Transistor Pinned Photo Diode (6TPPD) pixels with ˜135μV/electron sensitivity and a highly parallel signal chain. These new detectors are fabricated on 10μm epitaxial silicon and have a 1k by 1k format. We present details of our camera design and device performance with particular emphasis on those aspects of interest to single photon counting X-ray astronomy. These features include read noise, X-ray spectral response and quantum efficiency.

  19. An assembly-type master-slave catheter and guidewire driving system for vascular intervention.

    PubMed

    Cha, Hyo-Jeong; Yi, Byung-Ju; Won, Jong Yun

    2017-01-01

    Current vascular intervention inevitably exposes a large amount of X-ray to both an operator and a patient during the procedure. The purpose of this study is to propose a new catheter driving system which assists the operator in aspects of less X-ray exposure and convenient user interface. For this, an assembly-type 4-degree-of-freedom master-slave system was designed and tested to verify the efficiency. First, current vascular intervention procedures are analyzed to develop a new robotic procedure that enables us to use conventional vascular intervention devices such as catheter and guidewire which are commercially available in the market. Some parts of the slave robot which contact the devices were designed to be easily assembled and dissembled from the main body of the slave robot for sterilization. A master robot is compactly designed to conduct insertion and rotational motion and is able to switch from the guidewire driving mode to the catheter driving mode or vice versa. A phantom resembling the human arteries was developed, and the master-slave robotic system is tested using the phantom. The contact force of the guidewire tip according to the shape of the arteries is measured and reflected to the user through the master robot during the phantom experiment. This system can drastically reduce radiation exposure by replacing human effort by a robotic system for high radiation exposure procedures. Also, benefits of the proposed robot system are low cost by employing currently available devices and easy human interface.

  20. Rapid synthesis and decoration of reduced graphene oxide with gold nanoparticles by thermostable peptides for memory device and photothermal applications.

    PubMed

    Otari, Sachin V; Kumar, Manoj; Anwar, Muhammad Zahid; Thorat, Nanasaheb D; Patel, Sanjay K S; Lee, Dongjin; Lee, Jai Hyo; Lee, Jung-Kul; Kang, Yun Chan; Zhang, Liaoyuan

    2017-09-08

    This article presents novel, rapid, and environmentally benign synthesis method for one-step reduction and decoration of graphene oxide with gold nanoparticles (NAuNPs) by using thermostable antimicrobial nisin peptides to form a gold-nanoparticles-reduced graphene oxide (NAu-rGO) nanocomposite. The formed composite material was characterized by UV/Vis spectroscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and high-resolution transmission electron microscopy (HR-TEM). HR-TEM analysis revealed the formation of spherical AuNPs of 5-30 nm in size on reduced graphene oxide (rGO) nanosheets. A non-volatile-memory device was prepared based on a solution-processed ZnO thin-film transistor fabricated by inserting the NAu-rGO nanocomposite in the gate dielectric stack as a charge trapping medium. The transfer characteristic of the ZnO thin-film transistor memory device showed large clockwise hysteresis behaviour because of charge carrier trapping in the NAu-rGO nanocomposite. Under positive and negative bias conditions, clear positive and negative threshold voltage shifts occurred, which were attributed to charge carrier trapping and de-trapping in the ZnO/NAu-rGO/SiO 2 structure. Also, the photothermal effect of the NAu-rGO nanocomposites on MCF7 breast cancer cells caused inhibition of ~80% cells after irradiation with infrared light (0.5 W cm -2 ) for 5 min.

  1. Non-resonant inelastic x-ray scattering spectra of lithiated titanium oxides for battery applications

    NASA Astrophysics Data System (ADS)

    Nagle, Kenneth; Balasubramanian, Mali; Johnson, Christopher; Seidler, Gerald; Belharouak, Ilias

    2008-03-01

    Although lithium-ion batteries now see widespread use, there remain considerable questions concerning the basic solid state chemistry of both electrodes. Improved understanding of the local electronic structure, particularly the mechanism of charge transfer upon insertion and removal of lithium, could lead to innovation in battery design and improved performance. We present non-resonant inelastic x-ray scattering (NRIXS) spectra from 2p initial states in titanium; these spectra are among the first recorded for such states in a transition metal. These spectra were obtained using the lower energy resolution inelastic x-ray scattering (LERIX) spectrometer, which is capable of making simultaneous measurements at nineteen values of momentum transfer. We demonstrate the ability to obtain soft x-ray absorption-like information using a bulk-sensitive, hard x-ray technique. In addition, at high momentum transfer NRIXS provides information about non-dipole transitions that are inaccessible by soft x-ray spectroscopic methods.

  2. REVIEWS OF TOPICAL PROBLEMS: Recent advances in X-ray refractive optics

    NASA Astrophysics Data System (ADS)

    Aristov, V. V.; Shabel'nikov, L. G.

    2008-01-01

    X-ray refractive optics has made rapid strides to a large degree due to the work of Russian scientists, and has now become one of the most rapidly advancing areas in modern physical optics. This review outlines the results of investigation of refractive devices and analysis of their properties. The conception of planar lenses made of silicon and other materials is set forth. We discuss the applications of refractive lenses to the transformation of X-ray images, photonic crystal research, and the development of focusing devices in high-energy X-ray telescopes.

  3. Small area silicon diffused junction X-ray detectors

    NASA Technical Reports Server (NTRS)

    Walton, J. T.; Pehl, R. H.; Larsh, A. E.

    1982-01-01

    The low-temperature performance of silicon diffused junction detectors in the measurement of low energy X-rays is reported. The detectors have an area of 0.04 sq cm and a thickness of 100 microns. The spectral resolutions of these detectors were found to be in close agreement with expected values, indicating that the defects introduced by the high-temperature processing required in the device fabrication were not deleteriously affecting the detection of low-energy X-rays. Device performance over a temperature range of 77 K to 150 K is given. These detectors were designed to detect low-energy X-rays in the presence of minimum ionizing electrons. The successful application of silicon-diffused junction technology to X-ray detector fabrication may facilitate the development of other novel silicon X-ray detector designs.

  4. Analysis and Optimization of Thin Film Ferroelectric Phase Shifters

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R.; VanKeuls, Fred W.; Warner, Joseph D.; Mueller, Carl H.; Alterovitz, Samuel A.; Miranda, Felix A.; Qureshi, A. Haq; Romanofsky, Robert R. (Technical Monitor)

    2000-01-01

    Microwave phase shifters have been fabricated from (YBa2Cu3O(7-delta) or Au)/SrTiO3 and Au/Ba(x)Sr(1-x)TiO3 films on LaAlO3 and MgO substrates. These coupled microstrip devices rival the performance of their semiconductor counter-parts parts at Ku- and K-band frequencies. Typical insertion loss for room temperature ferroelectric phase shifters at K-band is approximately equal 5 dB. An experimental and theoretical investigation of these novel devices explains the role of the ferroelectric film in overall device performance. A roadmap to the development of a 3 dB insertion loss phase shifter that would enable a new type of phased array antenna is discussed.

  5. A method of measuring gold nanoparticle concentrations by x-ray fluorescence for biomedical applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu Di; Li Yuhua; Wong, Molly D.

    Purpose: This paper reports a technique that enables the quantitative determination of the concentration of gold nanoparticles (GNPs) through the accurate detection of their fluorescence radiation in the diagnostic x-ray spectrum. Methods: Experimentally, x-ray fluorescence spectra of 1.9 and 15 nm GNP solutions are measured using an x-ray spectrometer, individually and within chicken breast tissue samples. An optimal combination of excitation and emission filters is determined to segregate the fluorescence spectra at 66.99 and 68.80 keV from the background scattering. A roadmap method is developed that subtracts the scattered radiation (acquired before the insertion of GNP solutions) from the signalmore » radiation acquired after the GNP solutions are inserted. Results: The methods effectively minimize the background scattering in the spectrum measurements, showing linear relationships between GNP solutions from 0.1% to 10% weight concentration and from 0.1% to 1.0% weight concentration inside a chicken breast tissue sample. Conclusions: The investigation demonstrated the potential of imaging gold nanoparticles quantitatively in vivo for in-tissue studies, but future studies will be needed to investigate the ability to apply this method to clinical applications.« less

  6. Evaluation of the need for chest X-rays in the management of asymptomatic, intraluminal vascular access device occlusion in childhood cancer.

    PubMed

    Stammers, David; Connolly, Bairbre; Brandão, Leonardo R; Zupanec, Sue; Gupta, Sumit

    2017-07-01

    Venous access device (VAD) occlusion from intraluminal thrombus is a common complication during childhood cancer treatment. Current practice at many institutions is to assess VAD position with a chest X-ray (CXR) prior to intraluminal administration of tissue plasminogen activator (tPA). We aimed to determine the utility of this practice. A retrospective chart review of children with newly diagnosed cancer with a VAD, treated at The Hospital for Sick Children between 2010 and 2011, was performed. Episodes of line occlusion were identified both by reviewing patient CXRs for indication and identifying tPA doses dispensed. These episodes were reviewed to determine whether CXR findings resulted in management other than tPA. Cases in which the X-ray resulted in a change in management were further reviewed to determine whether administration of tPA could have resulted in potential patient harm. A total of 330 patients with newly diagnosed cancer with VADs were identified. Eighty-five (25.8%) patients experienced 123 episodes of VAD occlusion. VAD occlusions occurred more frequently in patients with tunneled external central venous lines (16/39, 41.5%) and peripherally inserted central catheters (PICC) (27/73, 37.0%) versus PORT (42/216, 19.4%; P = 0.001). There were nine (8.1%) episodes of VAD occlusion evaluated with a CXR in which the findings led to a change in management other than administering tPA. In each case, multiple specialists independently concluded that administration of tPA would have been unlikely to cause patient harm. Routine CXRs prior to the administration of tPA for asymptomatic VAD occlusion can safely be omitted. © 2016 Wiley Periodicals, Inc.

  7. Conceptual design of front ends for the advanced photon source multi-bend achromats upgrade

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jaski, Y., E-mail: jaskiy@aps.anl.gov; Westferro, F., E-mail: westferr@aps.anl.gov; Lee, S. H., E-mail: shlee@aps.anl.gov

    2016-07-27

    The proposed Advanced Photon Source (APS) upgrade from a double-bend achromats (DBA) to multi-bend achromats (MBA) lattice with ring energy change from 7 GeV to 6 GeV and beam current from 100 mA to 200 mA poses new challenges for front ends. All front ends must be upgraded to fulfill the following requirements: 1) handle the high heat load from two insertion devices in either inline or canted configuration, 2) include a clearing magnet in the front end to deflect and dump any electrons in case the electrons escape from the storage ring during swap-out injection with the safety shuttersmore » open, 3) incorporate the next generation x-ray beam position monitors (XBPMs) into the front end to meet the new stringent beam stability requirements. This paper presents the evaluation of the existing APS front ends and standardizes the insertion device (ID) front ends into two types: one for the single beam and one for the canted beams. The conceptual design of high heat load front end (HHLFE) and canted undulator front end (CUFE) for APS MBA upgrade is presented.« less

  8. Conceptual Design of Front Ends for the Advanced Photon Source Multi-bend Achromats Upgrade

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jaski, Y.; Westferro, F.; Lee, S. H.

    2016-07-27

    The proposed Advanced Photon Source (APS) upgrade from a double-bend achromats (DBA) to multi-bend achromats (MBA) lattice with ring energy change from 7 GeV to 6 GeV and beam current from 100 mA to 200 mA poses new challenges for front ends. All front ends must be upgraded to fulfill the following requirements: 1) handle the high heat load from two insertion devices in either inline or canted configuration, 2) include a clearing magnet in the front end to deflect and dump any electrons in case the electrons escape from the storage ring during swap-out injection with the safety shuttersmore » open, 3) incorporate the next generation x-ray beam position monitors (XBPMs) into the front end to meet the new stringent beam stability requirements. This paper presents the evaluation of the existing APS front ends and standardizes the insertion device (ID) front ends into two types: one for the single beam and one for the canted beams. The conceptual design of high heat load front end (HHLFE) and canted undulator front end (CUFE) for APS MBA upgrade is presented.« less

  9. Comparative analysis of ex-situ and operando X-ray diffraction experiments for lithium insertion materials

    NASA Astrophysics Data System (ADS)

    Brant, William R.; Li, Dan; Gu, Qinfen; Schmid, Siegbert

    2016-01-01

    A comparative study of ex-situ and operando X-ray diffraction techniques using the fast lithium ion conductor Li0.18Sr0.66Ti0.5Nb0.5O3 is presented. Ex-situ analysis of synchrotron X-ray diffraction data suggests that a single phase material exists for all discharges to as low as 0.422 V. For samples discharged to 1 V or lower, i.e. with higher lithium content, it is possible to determine the lithium position from the X-ray data. However, operando X-ray diffraction from a coin cell reveals that a kinetically driven two phase region occurs during battery cycling below 1 V. Through monitoring the change in unit cell dimension during electrochemical cycling the dynamics of lithium insertion are explored. A reduction in the rate of unit cell expansion of 22(2)% part way through the first discharge and 13(1)% during the second discharge is observed. This reduction may be caused by a drop in lithium diffusion into the bulk material for higher lithium contents. A more significant change is a jump in the unit cell expansion by 60(2)% once the lithium content exceeds one lithium ion per vacant site. It is suggested that this jump is caused by damping of octahedral rotations, thus establishing a link between lithium content and octahedral rotations.

  10. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Image-intensified fluoroscopic x-ray system. 892... fluoroscopic x-ray system. (a) Identification. An image-intensified fluoroscopic x-ray system is a device intended to visualize anatomical structures by converting a pattern of x-radiation into a visible image...

  11. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Image-intensified fluoroscopic x-ray system. 892... fluoroscopic x-ray system. (a) Identification. An image-intensified fluoroscopic x-ray system is a device intended to visualize anatomical structures by converting a pattern of x-radiation into a visible image...

  12. Framework for computing the spatial coherence effects of polycapillary x-ray optics

    PubMed Central

    Zysk, Adam M.; Schoonover, Robert W.; Xu, Qiaofeng; Anastasio, Mark A.

    2012-01-01

    Despite the extensive use of polycapillary x-ray optics for focusing and collimating applications, there remains a significant need for characterization of the coherence properties of the output wavefield. In this work, we present the first quantitative computational method for calculation of the spatial coherence effects of polycapillary x-ray optical devices. This method employs the coherent mode decomposition of an extended x-ray source, geometric optical propagation of individual wavefield modes through a polycapillary device, output wavefield calculation by ray data resampling onto a uniform grid, and the calculation of spatial coherence properties by way of the spectral degree of coherence. PMID:22418154

  13. Application of MEMS-based x-ray optics as tuneable nanosecond choppers

    NASA Astrophysics Data System (ADS)

    Chen, Pice; Walko, Donald A.; Jung, Il Woong; Li, Zhilong; Gao, Ya; Shenoy, Gopal K.; Lopez, Daniel; Wang, Jin

    2017-08-01

    Time-resolved synchrotron x-ray measurements often rely on using a mechanical chopper to isolate a set of x-ray pulses. We have started the development of micro electromechanical systems (MEMS)-based x-ray optics, as an alternate method to manipulate x-ray beams. In the application of x-ray pulse isolation, we recently achieved a pulse-picking time window of half a nanosecond, which is more than 100 times faster than mechanical choppers can achieve. The MEMS device consists of a comb-drive silicon micromirror, designed for efficiently diffracting an x-ray beam during oscillation. The MEMS devices were operated in Bragg geometry and their oscillation was synchronized to x-ray pulses, with a frequency matching subharmonics of the cycling frequency of x-ray pulses. The microscale structure of the silicon mirror in terms of the curvature and the quality of crystallinity ensures a narrow angular spread of the Bragg reflection. With the discussion of factors determining the diffractive time window, this report showed our approaches to narrow down the time window to half a nanosecond. The short diffractive time window will allow us to select single x-ray pulse out of a train of pulses from synchrotron radiation facilities.

  14. Energy spectrum of multi-radiation of X-rays in a low energy Mather-type plasma focus device

    NASA Astrophysics Data System (ADS)

    Farzin, M. Aghamir; Reza, A. Behbahani

    2014-06-01

    The multi-radiation of X-rays was investigated with special attention to their energy spectrum in a Mather-type plasma focus device (operated with argon gas). The analysis is based on the effect of anomalous resistances. To study the energy spectrum, a four-channel diode X-ray spectrometer was used along with a special set of filters. The filters were suitable for detection of medium range X-rays as well as hard X-rays with energy exceeding 30 keV. The results indicate that the anomalous resistivity effect during the post pinch phase may cause multi-radiation of X-rays with a total duration of 300 ± 50 ns. The significant contribution of Cu—Kα was due to the medium range X-rays, nonetheless, hard X-rays with energies greater than 15 keV also participate in the process. The total emitted X-ray energy in the forms of Cu—Kα and Cu—Kβ was around 0.14 ± 0.02 (J/Sr) and 0.04 ± 0.01 (J/Sr), respectively. The total energy of the emitted hard X-ray (> 15 keV) was around 0.12 ± 0.02 (J/Sr).

  15. Kilopixel X-Ray Microcalorimeter Arrays for Astrophysics: Device Performance and Uniformity

    NASA Technical Reports Server (NTRS)

    Eckart, M. E.; Adams, J. S.; Bailey, C. N.; Bandler, S. R.; Busch, S. E.; Chervenak, J. A.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.; hide

    2012-01-01

    We are developing kilopixel arrays of TES microcalorimeters to enable high-resolution x-ray imaging spectrometers for future x-ray observatories and laboratory astrophysics experiments. Our current array design was targeted as a prototype for the X-ray Microcalorimeter Spectrometer proposed for the International X-ray Observatory, which calls for a 40×40-pixel core array of 300 micron devices with 2.5 eV energy resolution (at 6 keV). Here we present device characterization of our 32×32 arrays, including x-ray spectral performance of individual pixels within the array. We present our results in light of the understanding that our Mo/Au TESs act as weak superconducting links, causing the TES critical current (I(sub c)) and transition shape to oscillate with applied magnetic field (B). We show I(sub c)(B) measurements and discuss the uniformity of these measurements across the array, as well as implications regarding the uniformity of device noise and response. In addition, we are working to reduce pixel-to-pixel electrical and thermal crosstalk; we present recent test results from an array that has microstrip wiring and an angle-evaporated copper backside heatsinking layer, which provides copper coverage on the four sidewalls of the silicon wells beneath each pixel.

  16. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murray, Thomas D.; Johns Hopkins University School of Medicine, Baltimore, MD 21205; Lyubimov, Artem Y.

    A highly X-ray-transparent, silicon nitride-based device has been designed and fabricated to harvest protein microcrystals for high-resolution X-ray diffraction data collection using microfocus beamlines and XFELs. Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming themore » challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.« less

  17. Miniaturized High-Speed Modulated X-Ray Source

    NASA Technical Reports Server (NTRS)

    Gendreau, Keith C. (Inventor); Arzoumanian, Zaven (Inventor); Kenyon, Steven J. (Inventor); Spartana, Nick Salvatore (Inventor)

    2015-01-01

    A miniaturized high-speed modulated X-ray source (MXS) device and a method for rapidly and arbitrarily varying with time the output X-ray photon intensities and energies. The MXS device includes an ultraviolet emitter that emits ultraviolet light, a photocathode operably coupled to the ultraviolet light-emitting diode that emits electrons, an electron multiplier operably coupled to the photocathode that multiplies incident electrons, and an anode operably coupled to the electron multiplier that is configured to produce X-rays. The method for modulating MXS includes modulating an intensity of an ultraviolet emitter to emit ultraviolet light, generating electrons in response to the ultraviolet light, multiplying the electrons to become more electrons, and producing X-rays by an anode that includes a target material configured to produce X-rays in response to impact of the more electrons.

  18. Wavefront propagation simulations for a UV/soft x-ray beamline: Electron Spectro-Microscopy beamline at NSLS-II

    NASA Astrophysics Data System (ADS)

    Canestrari, N.; Bisogni, V.; Walter, A.; Zhu, Y.; Dvorak, J.; Vescovo, E.; Chubar, O.

    2014-09-01

    A "source-to-sample" wavefront propagation analysis of the Electron Spectro-Microscopy (ESM) UV / soft X-ray beamline, which is under construction at the National Synchrotron Light Source II (NSLS-II) in the Brookhaven National Laboratory, has been conducted. All elements of the beamline - insertion device, mirrors, variable-line-spacing gratings and slits - are included in the simulations. Radiation intensity distributions at the sample position are displayed for representative photon energies in the UV range (20 - 100 eV) where diffraction effects are strong. The finite acceptance of the refocusing mirrors is the dominating factor limiting the spatial resolution at the sample (by ~3 μm at 20 eV). Absolute estimates of the radiation flux and energy resolution at the sample are also obtained from the electromagnetic calculations. The analysis of the propagated UV range undulator radiation at different deflection parameter values demonstrates that within the beamline angular acceptance a slightly "red-shifted" radiation provides higher flux at the sample and better energy resolution compared to the on-axis resonant radiation of the fundamental harmonic.

  19. X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fournier, K. B., E-mail: fournier2@llnl.gov; Brown, C. G.; Yeoman, M. F.

    2016-11-15

    Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the National Ignition Facility’s diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built-in calorimeters give in situ measurements of the x-ray environment along the sample lines ofmore » sight. The measured accuracy of sample responses as well as planned modifications to the XTRRA cassette is discussed.« less

  20. X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility

    DOE PAGES

    Fournier, K. B.; Brown, Jr., C. G.; Yeoman, M. F.; ...

    2016-08-10

    Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the NIF’s diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built in calorimeters give in situ measurements of the x-ray environment along the sample lines of sight.more » We discuss the measured accuracy of sample responses, as well as planned modifications to the XTRRA cassette.« less

  1. Tunable anomalous hall effect induced by interfacial catalyst in perpendicular multilayers

    NASA Astrophysics Data System (ADS)

    Zhang, J. Y.; Peng, W. L.; Sun, Q. Y.; Liu, Y. W.; Dong, B. W.; Zheng, X. Q.; Yu, G. H.; Wang, C.; Zhao, Y. C.; Wang, S. G.

    2018-04-01

    The interfacial structures, playing a critical role on the transport properties and the perpendicular magnetic anisotropy in thin films and multilayers, can be modified by inserting an ultrathin functional layer at the various interfaces. The anomalous Hall effect (AHE) in the multilayers with core structure of Ta/CoFeB/X/MgO/Ta (X: Hf or Pt) is tuned by interfacial catalytic engineering. The saturation anomalous Hall resistance (RAH) is increased by 16.5% with 0.1 nm Hf insertion compared with the reference sample without insertion. However, the RAH value is decreased by 9.0% with 0.1 nm Pt insertion. The interfacial states were characterized by the X-ray photoelectron spectroscopy (XPS). The XPS results indicate that a strong bonding between Hf and O for Hf insertion, but no bonding between Pt and O for Pt insertion. The bonding between metal and oxygen leads to various oxygen migration behavior at the interfaces. Therefore, the opposite behavior about the RAH originates from the different oxygen behavior due to various interfacial insertion. This work provides a new approach to manipulate spin transport property for the potential applications.

  2. Refractive optics to compensate x-ray mirror shape-errors

    NASA Astrophysics Data System (ADS)

    Laundy, David; Sawhney, Kawal; Dhamgaye, Vishal; Pape, Ian

    2017-08-01

    Elliptically profiled mirrors operating at glancing angle are frequently used at X-ray synchrotron sources to focus X-rays into sub-micrometer sized spots. Mirror figure error, defined as the height difference function between the actual mirror surface and the ideal elliptical profile, causes a perturbation of the X-ray wavefront for X- rays reflecting from the mirror. This perturbation, when propagated to the focal plane results in an increase in the size of the focused beam. At Diamond Light Source we are developing refractive optics that can be used to locally cancel out the wavefront distortion caused by figure error from nano-focusing elliptical mirrors. These optics could be used to correct existing optical components on synchrotron radiation beamlines in order to give focused X-ray beam sizes approaching the theoretical diffraction limit. We present our latest results showing measurement of the X-ray wavefront error after reflection from X-ray mirrors and the translation of the measured wavefront into a design for refractive optical elements for correction of the X-ray wavefront. We show measurement of the focused beam with and without the corrective optics inserted showing reduction in the size of the focus resulting from the correction to the wavefront.

  3. X-ray emission from high temperature plasmas

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1977-01-01

    The physical processes occurring in plasma focus devices were investigated with particular emphasis on X-ray emission. Topics discussed include: trajectories of high energy electrons; detection of ion trajectories; spatial distribution of neutron emission; space and time resolved emission of hard X-rays from a plasma focus; the staged plasma focus as a variation of the hypocloidal pinch; formation of current sheets in a staged plasma focus; and X-ray and neutron emission from a staged plasma focus. The possibility of operating dense plasma-focus type devices in multiple arrays beyond the scaling law for a single gun is discussed.

  4. Anti-contamination device for cryogenic soft X-ray diffraction microscopy

    DOE PAGES

    Huang, Xiaojing; Miao, Huijie; Nelson, Johanna; ...

    2011-05-01

    Cryogenic microscopy allows one to view frozen hydrated biological and soft matter specimens with good structural preservation and a high degree of stability against radiation damage. We describe a liquid nitrogen-cooled anti-contamination device for cryogenic X-ray diffraction microscopy. The anti-contaminator greatly reduces the buildup of ice layers on the specimen due to condensation of residual water vapor in the experimental vacuum chamber. We show by coherent X-ray diffraction measurements that this leads to fivefold reduction of background scattering, which is important for far-field X-ray diffraction microscopy of biological specimens.

  5. Zero-P: a new zero-profile cage-plate device for single and multilevel ACDF. A single institution series with four years maximum follow-up and review of the literature on zero-profile devices.

    PubMed

    Barbagallo, Giuseppe M V; Romano, Dario; Certo, Francesco; Milone, Pietro; Albanese, Vincenzo

    2013-11-01

    To analyze the prospectively collected data in a series of patients treated with single- or multilevel ACDF with a stand-alone, zero-profile device, focusing on clinico-radiological outcome, complications and technical hints, and to review the literature on such new devices. Eighty-five patients harboring symptomatic DDD underwent ACDF with the Zero-P cage-plate: 29 at 1-level and 56 at 2-4 levels (total 162 devices). In the multilevel group, 9 patients received a combination of Zero-P and stand-alone cages (hybrid implants). This study focuses on 32 patients with follow-up ranging from 20 to 48 months. NDI, SF-36 and arm pain VAS scores were registered preoperatively and at follow-up visits. Dysphagia was assessed using the Bazaz score. Imaging included X-rays, CT and MRI, also to assess the presence of vertebral body fractures in multilevel cases. Paired Student t test was used for statistical analysis. SF-36 and NDI showed a statistically significant improvement (p < 0.01) and mean arm pain VAS score decreased from 79 to 41. X-rays and CT demonstrated, respectively, a 94.5 % and a 92 % fusion rate. Three patients complained of moderate and two of mild transient dysphagia (15.5 %). No device-related complications occurred and no fractures, secondary to four screws insertion in one vertebral body (i.e., swiss cheese effect), were detected in multilevel cases. In patients with extensive anterior osteophytes only a "focal spondylectomy" was required. The Zero-P device is safe and efficient, even in multilevel cases. Dysphagia is minimal, extensive anterior osteophytectomy is unnecessary and technical hints may ease the surgical workflow. This is the largest series, with the longest follow-up, reported.

  6. Effect of insulator sleeve material on the x-ray emission from a plasma focus device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hussain, S.; Badar, M. A.; Shafiq, M.

    The effect of insulator sleeve material on x-ray emission from a 2.3 kJ Mather type plasma focus device operated in argon-hydrogen mixture is investigated. The time and space resolved x-ray emission characteristics are studied by using a three channel p-i-n diode x-ray spectrometer and a multipinhole camera. The x-ray emission depends on the volumetric ratio of argon-hydrogen mixture as well as the filling pressure and the highest x-ray emission is observed for a volumetric ratio 40% Ar to 60%H{sub 2} at 2.5 mbar filling pressure. The fused silica insulator sleeve produces the highest x-ray emission whereas nonceramic insulator sleeves suchmore » as nylon, Perspex, or Teflon does not produce focus or x-rays. The pinhole images of the x-ray emitting zones reveal that the contribution of the Cu K{alpha} line is weak and plasma x-rays are intense. The highest plasma electron temperature is estimated to be 3.3 and 3.6 keV for Pyrex glass and fused silica insulator sleeves, respectively. It is speculated that the higher surface resistivity of fused silica is responsible for enhanced x-ray emission and plasma electron temperature.« less

  7. Improved intensifying screen reduces X-ray exposure

    NASA Technical Reports Server (NTRS)

    Buchanan, R. A.

    1972-01-01

    X-ray intensifying screen may make possible radiographic procedures where detection speed and X-ray tube power have been the limiting factors. Device will reduce total population exposure to harmful radiation in the United States.

  8. NiTiNol Hernia Device Stability in Inguinal Hernioplasty Without Fixation

    PubMed Central

    2011-01-01

    Background and Objective: To determine whether the NiTiNol frame of a novel hernia repair device utilizing polypropylene mesh for inguinal hernioplasty remains stable and intransient without fixation after a minimum of 6 months. Methods: Twenty patients had 27 inguinal hernias repaired using a novel hernia repair device that has a NiTiNol frame without any fixation. Initial single-view, postoperative X-rays were compared with a second X-ray obtained at least 6 months later. The NiTiNol frame, which can be easily visualized on a plain X-ray, was measured in 2 dimensions, as were anatomic landmarks. The measurements obtained and the appearances of the 2 X-rays were compared to determine the percentage of change in device size and device stability with regard to device location and shape. Results: There were minimal changes noted between the 2 sets of measurements obtained with an overall trend towards a slight increase in the size of the hernia repair device. The devices demonstrated intransience of position and stability of shape. Conclusions: The NiTiNol frame of a novel hernia repair device utilizing polypropylene mesh exhibits radiographic evidence of size and shape stability and intransience of position without fixation when used in inguinal hernioplasty after a minimum follow-up of 6 months. PMID:21902967

  9. [The validation of the parameters for a basic model of a power supply layout for general x-ray diagnostic apparatus].

    PubMed

    Blinov, N N

    2000-01-01

    Specifications for the main element of a modern X-ray diagnostic device an X-ray feeder are formulated. There is evidence for choosing its parameters. The new rational routine of X-ray study and the layout of a X-ray room are proposed. Information on the up-to-date commercially manufactured basic medium-frequency general-purpose X-ray feeder "URP-30 SCh Amico" is given.

  10. Diffraction leveraged modulation of X-ray pulses using MEMS-based X-ray optics

    DOEpatents

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

    2016-08-09

    A method and apparatus are provided for implementing Bragg-diffraction leveraged modulation of X-ray pulses using MicroElectroMechanical systems (MEMS) based diffractive optics. An oscillating crystalline MEMS device generates a controllable time-window for diffraction of the incident X-ray radiation. The Bragg-diffraction leveraged modulation of X-ray pulses includes isolating a particular pulse, spatially separating individual pulses, and spreading a single pulse from an X-ray pulse-train.

  11. [Characteristics of specifications of transportable inverter-type X-ray equipment].

    PubMed

    Yamamoto, Keiichi; Miyazaki, Shigeru; Asano, Hiroshi; Shinohara, Fuminori; Ishikawa, Mitsuo; Ide, Toshinori; Abe, Shinji; Negishi, Toru; Miyake, Hiroyuki; Imai, Yoshio; Okuaki, Tomoyuki

    2003-07-01

    Our X-ray systems study group measured and examined the characteristics of four transportable inverter-type X-ray equipments. X-ray tube voltage and X-ray tube current were measured with the X-ray tube voltage and the X-ray tube current measurement terminals provided with the equipment. X-ray tube voltage, irradiation time, and dose were measured with a non-invasive X-ray tube voltage-measuring device, and X-ray output was measured by fluorescence meter. The items investigated were the reproducibility and linearity of X-ray output, error of pre-set X-ray tube voltage and X-ray tube current, and X-ray tube voltage ripple percentage. The waveforms of X-ray tube voltage, the X-ray tube current, and fluorescence intensity draw were analyzed using the oscilloscope gram and a personal computer. All of the equipment had a preset error of X-ray tube voltage and X-ray tube current that met JIS standards. The X-ray tube voltage ripple percentage of each equipment conformed to the tendency to decrease when X-ray tube voltage increased. Although the X-ray output reproducibility of system A exceeded the JIS standard, the other systems were within the JIS standard. Equipment A required 40 ms for X-ray tube current to reach the target value, and there was some X-ray output loss because of a trough in X-ray tube current. Owing to the influence of the ripple in X-ray tube current, the strength of the fluorescence waveform rippled in equipments B and C. Waveform analysis could not be done by aliasing of the recording device in equipment D. The maximum X-ray tube current of transportable inverter-type X-ray equipment is as low as 10-20 mA, and the irradiation time of chest X-ray photography exceeds 0.1 sec. However, improvement of the radiophotographic technique is required for patients who cannot move their bodies or halt respiration. It is necessary to make the irradiation time of the equipments shorter for remote medical treatment.

  12. Electromagnetic radiation screening of microcircuits for long life applications

    NASA Technical Reports Server (NTRS)

    Brammer, W. G.; Erickson, J. J.; Levy, M. E.

    1974-01-01

    The utility of X-rays as a stimulus for screening high reliability semiconductor microcircuits was studied. The theory of the interaction of X-rays with semiconductor materials and devices was considered. Experimental measurements of photovoltages, photocurrents, and effects on specified parameters were made on discrete devices and on microcircuits. The test specimens included discrete devices with certain types of identified flaws and symptoms of flaws, and microcircuits exhibiting deviant electrical behavior. With a necessarily limited sample of test specimens, no useful correlation could be found between the X-ray-induced electrical response and the known or suspected presence of flaws.

  13. Improving Patient Safety with X-Ray and Anesthesia Machine Ventilator Synchronization: A Medical Device Interoperability Case Study

    NASA Astrophysics Data System (ADS)

    Arney, David; Goldman, Julian M.; Whitehead, Susan F.; Lee, Insup

    When a x-ray image is needed during surgery, clinicians may stop the anesthesia machine ventilator while the exposure is made. If the ventilator is not restarted promptly, the patient may experience severe complications. This paper explores the interconnection of a ventilator and simulated x-ray into a prototype plug-and-play medical device system. This work assists ongoing interoperability framework development standards efforts to develop functional and non-functional requirements and illustrates the potential patient safety benefits of interoperable medical device systems by implementing a solution to a clinical use case requiring interoperability.

  14. The effects of pre-ionization using a shunt resistor on reproducibility of the x-ray emission in a dense plasma focus device

    NASA Astrophysics Data System (ADS)

    Piriaei, D.; Yousefi, H. R.; Mahabadi, T. D.; SalarElahi, A.; Ghoranneviss, M.

    2017-08-01

    In this research, the effects of pre-ionization using a shunt resistor on reproducibility of x-ray emission in a Mather type plasma focus device have been studied. This technique increased the intensities of the emitted x-rays from argon as the filling gas of the device and made the x-ray yields with similar intensities reproducible. A Mirnov coil was also used to record the variations of the plasma's magnetic field, and the wavelet spectrums of these recorded signals showed the reduced instabilities due to the application of the pre-ionization technique. Moreover, it was demonstrated that this technique was capable of reducing the number of initial runaway electrons that could increase the impurities and instabilities inside the plasma. In addition to the above-mentioned features, this technique could improve the uniform formation of the current sheath during the breakdown phase that might later lead to a high quality pinch and high intensity emitted x-rays.

  15. The effects of pre-ionization on the impurity and x-ray level in a dense plasma focus device

    NASA Astrophysics Data System (ADS)

    Piriaei, D.; Yousefi, H. R.; Mahabadi, T. D.; Salar Elahi, A.; Ghoranneviss, M.

    2017-02-01

    In this study, the effects of pre-ionization on the reduction of the impurities and non-uniformities, the increased stability of the pinch plasma, the enhancement of the total hard x-ray yield, the plasmoid x-ray yield, and the current sheath dynamics of the argon gas at different pressures in a Mather type plasma focus device were investigated. For this purpose, different shunt resistors together with two x-ray detectors were used, and the data gathered from the x-ray signals showed that the optimum shunt resistor could cause the maximum total hard and plasmoid hard x-ray emissions. Moreover, in order to calculate the average speed of the current sheath, two axial magnetic probes were used. It was revealed that the pre-ionization could increase the whole range of the emitted x-rays and produce a more uniform current sheath layer, which moved faster, and this technique could lead to the reduction of the impurities, creating a more stabilized pinched plasma, which was capable of emitting more x-rays than the usual case without using pre-ionization.

  16. Surface morphology and interdiffusion of LiF in Alq3-based organic light-emitting devices.

    PubMed

    Lee, Young Joo; Li, Xiaolong; Kang, Da-Yeon; Park, Seong-Sik; Kim, Jinwoo; Choi, Jeong-Woo; Kim, Hyunjung

    2008-09-01

    Highly efficient organic light-emitting devices (OLEDs) have been realized by insertion of a thin insulating lithium fluoride (LiF) layer between aluminum (Al) cathode and an electron transport layer, tris-(8-hydroxyquinoline) aluminum (Alq(3)). In this paper, we study the surface morphology of LiF on Alq(3) by synchrotron X-ray scattering and atomic force microscopy (AFM) as a function of thickness of LiF. We also study the interdiffusion of LiF into Al cathode as well as into Alq(3) layer as a function of temperature. Initially, LiF molecules are distributed randomly as clusters on the Alq(3) layer and then gradually form a layer as increasing LiF thickness. The interdiffusion of LiF into Al occurs more actively than into Alq(3) in annealing process. LiF on Alq(3) induces the ordering of Al to (111) direction strongly with increasing LiF thickness.

  17. Real-time "x-ray vision" for healthcare simulation: an interactive projective overlay system to enhance intubation training and other procedural training.

    PubMed

    Samosky, Joseph T; Baillargeon, Emma; Bregman, Russell; Brown, Andrew; Chaya, Amy; Enders, Leah; Nelson, Douglas A; Robinson, Evan; Sukits, Alison L; Weaver, Robert A

    2011-01-01

    We have developed a prototype of a real-time, interactive projective overlay (IPO) system that creates augmented reality display of a medical procedure directly on the surface of a full-body mannequin human simulator. These images approximate the appearance of both anatomic structures and instrument activity occurring within the body. The key innovation of the current work is sensing the position and motion of an actual device (such as an endotracheal tube) inserted into the mannequin and using the sensed position to control projected video images portraying the internal appearance of the same devices and relevant anatomic structures. The images are projected in correct registration onto the surface of the simulated body. As an initial practical prototype to test this technique we have developed a system permitting real-time visualization of the intra-airway position of an endotracheal tube during simulated intubation training.

  18. Significant Stability Enhancement in High-Efficiency Polymer:Fullerene Bulk Heterojunction Solar Cells by Blocking Ultraviolet Photons from Solar Light.

    PubMed

    Jeong, Jaehoon; Seo, Jooyeok; Nam, Sungho; Han, Hyemi; Kim, Hwajeong; Anthopoulos, Thomas D; Bradley, Donal D C; Kim, Youngkyoo

    2016-04-01

    Achievement of extremely high stability for inverted-type polymer:fullerene solar cells is reported, which have bulk heterojunction (BHJ) layers consisting of poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene-alt-3-fluorothieno[3,4-b]thiophene-2-carboxylate] (PTB7-Th) and [6,6]-phenyl-C71-butyric acid methyl ester (PC 71 BM), by employing UV-cut filter (UCF) that is mounted on the front of glass substrates. The UCF can block most of UV photons below 403 nm at the expense of ≈20% reduction in the total intensity of solar light. Results show that the PTB7-Th:PC 71 BM solar cell with UCF exhibits extremely slow decay in power conversion efficiency (PCE) but a rapidly decayed PCE is measured for the device without UCF. The poor device stability without UCF is ascribed to the oxidative degradation of constituent materials in the BHJ layers, which give rise to the formation of PC 71 BM aggregates, as measured with high resolution and scanning transmission electron microscopy and X-ray photoelectron spectroscopy. The device stability cannot be improved by simply inserting poly(ethylene imine) (PEI) interfacial layer without UCF, whereas the lifetime of the PEI-inserted PTB7-Th:PC 71 BM solar cells is significantly enhanced when UCF is attached.

  19. The effectiveness of ultrasonography in verifying the placement of a nasogastric tube in patients with low consciousness at an emergency center

    PubMed Central

    2012-01-01

    Background This study was designed to compare the effectiveness of using auscultation, pH measurements of gastric aspirates, and ultrasonography as physical examination methods to verify nasogastric tube(NGT) placement in emergency room patients with low consciousness who require NGT insertion. Methods The study included 47 patients who were all over 18 years of age. In all patients, tube placement was verified by chest X-rays. Auscultation, pH analysis of gastric aspirates, and ultrasonography were conducted on each patient in random order. The mean patient age was 57.62 ± 17.24 years, and 28 males (59.6%) and 19 females (40.4%) were included. The NGT was inserted by an emergency room resident. For pH testing, gastric aspirates were dropped onto litmus paper, and the resulting color of the paper was compared with a reference table. Ultrasonography was performed by an emergency medicine specialist, and the chest X-ray examination was interpreted by a different emergency medicine specialist who did not conduct the ultrasonography test. The results of the auscultation, gastric aspirate pH, and ultrasonography examinations were compared with the results of the chest x-ray examination. Results The sensitivity and specificity were 100% and 33.3%, respectively, for auscultation and 86.4% and 66.7%, respectively, for ultrasonography. Kappa values were the highest for auscultation at 0.484 compared to chest x-rays, followed by 0.299 for ultrasonography and 0.444 for pH analysis of the gastric aspirate. The ultrasonography has a positive predictive value of 97.4% and a negative predictive value of 25%. Conclusions Ultrasonography is useful for confirming the results of auscultation after NGT insertion among patients with low consciousness at an emergency center. When ultrasound findings suggest that the NGT placement is not gastric, additional chest X-ray should be performed. PMID:22691418

  20. The effectiveness of ultrasonography in verifying the placement of a nasogastric tube in patients with low consciousness at an emergency center.

    PubMed

    Kim, Hyung Min; So, Byung Hak; Jeong, Won Jung; Choi, Se Min; Park, Kyu Nam

    2012-06-12

    This study was designed to compare the effectiveness of using auscultation, pH measurements of gastric aspirates, and ultrasonography as physical examination methods to verify nasogastric tube(NGT) placement in emergency room patients with low consciousness who require NGT insertion. The study included 47 patients who were all over 18 years of age. In all patients, tube placement was verified by chest X-rays. Auscultation, pH analysis of gastric aspirates, and ultrasonography were conducted on each patient in random order. The mean patient age was 57.62 ± 17.24 years, and 28 males (59.6%) and 19 females (40.4%) were included. The NGT was inserted by an emergency room resident. For pH testing, gastric aspirates were dropped onto litmus paper, and the resulting color of the paper was compared with a reference table. Ultrasonography was performed by an emergency medicine specialist, and the chest X-ray examination was interpreted by a different emergency medicine specialist who did not conduct the ultrasonography test. The results of the auscultation, gastric aspirate pH, and ultrasonography examinations were compared with the results of the chest x-ray examination. The sensitivity and specificity were 100% and 33.3%, respectively, for auscultation and 86.4% and 66.7%, respectively, for ultrasonography. Kappa values were the highest for auscultation at 0.484 compared to chest x-rays, followed by 0.299 for ultrasonography and 0.444 for pH analysis of the gastric aspirate. The ultrasonography has a positive predictive value of 97.4% and a negative predictive value of 25%. Ultrasonography is useful for confirming the results of auscultation after NGT insertion among patients with low consciousness at an emergency center. When ultrasound findings suggest that the NGT placement is not gastric, additional chest X-ray should be performed.

  1. Elemental mapping and microimaging by x-ray capillary optics.

    PubMed

    Hampai, D; Dabagov, S B; Cappuccio, G; Longoni, A; Frizzi, T; Cibin, G; Guglielmotti, V; Sala, M

    2008-12-01

    Recently, many experiments have highlighted the advantage of using polycapillary optics for x-ray fluorescence studies. We have developed a special confocal scheme for micro x-ray fluorescence measurements that enables us to obtain not only elemental mapping of the sample but also simultaneously its own x-ray imaging. We have designed the prototype of a compact x-ray spectrometer characterized by a spatial resolution of less than 100 microm for fluorescence and less than 10 microm for imaging. A couple of polycapillary lenses in a confocal configuration together with a silicon drift detector allow elemental studies of extended samples (approximately 3 mm) to be performed, while a CCD camera makes it possible to record an image of the same samples with 6 microm spatial resolution, which is limited only by the pixel size of the camera. By inserting a compound refractive lens between the sample and the CCD camera, we hope to develop an x-ray microscope for more enlarged images of the samples under test.

  2. Enhanced sensitivity to near-infrared with high fill factor in small molecular organic solar cells

    NASA Astrophysics Data System (ADS)

    Shim, Hyun-Sub; Kim, Hyo Jung; Kim, Ji Whan; Kim, Sei-Yong; Jeong, Won-Ik; Kim, Tae-Min; Kim, Jang-Joo

    2012-09-01

    High efficiency near-infrared (NIR) absorbing solar cells based on lead phthalocyanine (PbPc) are reported using copper iodide (CuI) as a templating layer to control the crystal structure of PbPc. Devices with CuI inserted between the ITO and PbPc layers exhibit a two times enhancement of the JSC compared to the case in the absence of the CuI layer. This is due to the increase of crystallinity in the molecules grown on the CuI templating layer, which is investigated via an x-ray diffraction study. Moreover, fill factor is also enhanced to 0.63 from 0.57 due to low series resistance although the additional CuI layer is inserted between the ITO and the PbPc layer. As a result, the corrected power conversion efficiency of 2.5% was obtained, which is the highest one reported up to now among the PbPc based solar cells.

  3. Mechanisms for sodium insertion in carbon materials

    NASA Astrophysics Data System (ADS)

    Stevens, David Andrew

    2000-12-01

    This thesis details the mechanisms for sodium insertion into different carbons using both electrochemical and vapour techniques. Room temperature electrochemical measurements were completed to examine the insertion and removal of sodium from soft (graphitizable) and nanoporous hard (non-graphitizable) carbons prepared by the heat treatment of organic precursors to a range of temperatures. The mechanisms identified from these studies were further investigated through a series of in situ x-ray scattering studies on operating electrochemical cells. The results obtained were then compared with x-ray scattering measurements on carbons after exposure to sodium vapour at 890C. This work is primarily driven by the aluminium industry's need to understand how sodium insertion causes carbon cathode blocks in aluminium reduction cells to swell. The results obtained are also of relevance to the lithium-ion battery field as they help to verify mechanisms proposed in the literature for lithium insertion into carbon hosts. Some carbons were also identified that could accommodate large amounts of sodium, making them attractive candidates for anodes in rechargeable sodium ion batteries. For soft carbons, the results showed that both sodium and lithium insert between approximately parallel carbon layers along the sloping voltage region of the electrochemical curves, increasing the average interlayer spacing. The sodium and lithium capacities decreased with increasing carbon heat treatment temperature. For the soft carbons studied, the sodium capacity was found to be consistently lower than the lithium capacity, implying that some lithium-accessible sites were unavailable for sodium insertion. The electrochemical profiles for the hard carbons also contained capacity along a sloping voltage region and, as with the soft carbons, this was shown to result from the insertion of sodium and lithium between approximately parallel carbon layers. In contrast to the soft carbons, however, the electrochemical profiles for the hard carbons also exhibited significant capacity along low voltage plateaus at chemical potentials close to the chemical potential of the metal. An in situ small angle x-ray scattering experimental method was therefore developed to examine changes in scattering from the nanopores during sodium and lithium insertion/removal. The results from this technique clearly showed that the low voltage plateau capacity resulted from the insertion of sodium and lithium into nanopores in the carbon.

  4. Application of the gas-discharge surge arresters in X-ray devices and low voltage instrumentation

    NASA Astrophysics Data System (ADS)

    Simon, V. A.; Gerasimov, V. A.; Kostrin, D. K.; Lisenkov, A. A.; Selivanov, L. M.; Uhov, A. A.

    2018-02-01

    Usage of the gas discharge in science and engineering is discussed. Application examples of the compact gas-discharge tubes in the X-ray devices and low voltage instrumentation appliances for the surge protection are presented.

  5. Nanofiber-Based Bulk-Heterojunction Organic Solar Cells Using Coaxial Electrospinning

    DTIC Science & Technology

    2012-01-01

    chains are likely oriented with the [010] direction, perpendicular to the substrate, in the fi lm device. Glancing incidence X - ray diffraction (GIXD...Electron and X - ray diffraction measurements were per- formed in order to study the structural order in annealed fi bers and devices. For reference... angle X - ray scattering (SAXS/WAXS) beamline 7.3.3 of the Advanced Light Source at Lawrence Berkeley National Laboratory at 10 keV (1.24 Å) from a bend

  6. X-ray inspection of arduous welds in rocket and space technology with the use of a microfocus X-ray apparatus

    NASA Astrophysics Data System (ADS)

    Potrakhov, N. N.; Potrakhov, E. N.; Usachev, E. Y.; Gnedin, M. M.; Voroschuk, D. V.; Shavrina, I. M.

    2017-07-01

    The article presents the design of a specialized X-ray machine to perform circumferential weld inspections various structural elements of air and space technology. Shows the main specifications of the device and describes a particular application of the apparatus. The results of the use of the device in conditions of real production on one of the local engine companies in the aircraft and space industry.

  7. Electrical interface characteristics (I-V), optical time of flight measurements, and the x-ray (20 keV) signal response of amorphous-selenium/crystalline-silicon heterojunction structures

    NASA Astrophysics Data System (ADS)

    Hunter, David M.; Ho, Chu An; Belev, George; De Crescenzo, Giovanni; Kasap, Safa O.; Yaffe, Martin J.

    2011-03-01

    We have investigated the dark current, optical TOF (time of flight) properties, and the X-ray response of amorphousselenium (a-Se)/crystalline-silicon (c-Si) heterostructures for application in digital radiography. The structures have been studied to determine if an x-ray generated electron signal, created in an a-Se layer, could be directly transferred to a c-Si based readout device such as a back-thinned CCD (charge coupled device). A simple first order band-theory of the structure indicates that x-ray generated electrons should transfer from the a-Se to the c-Si, while hole transfer from p-doped c-Si to the a-Se should be blocked, permitting a low dark signal as required. The structures we have tested have a thin metal bias electrode on the x-ray facing side of the a-Se which is deposited on the c-Si substrate. The heterostructures made with pure a-Se deposited on epitaxial p-doped (5×10 14 cm-3) c-Si exhibited very low dark current of 15 pA cm-2 at a negative bias field of 10 V μm-1 applied to the a-Se. The optical TOF (time of flight) measurements show that the applied bias drops almost entirely across the a-Se layer and that the a-Se hole and electron mobilities are within the range of commonly accepted values. The x-ray signal measurements demonstrate the structure has the expected x-ray quantum efficiency. We have made a back-thinned CCD coated with a-Se and although most areas of the device show a poor x-ray response, it does contain small regions which do work properly with the expected x-ray sensitivity. Improved understanding of the a-Se/c-Si interface and preparation methods should lead to properly functioning devices.

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

    NASA Astrophysics Data System (ADS)

    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.

  9. A low cost X-ray imaging device based on BPW-34 Si-PIN photodiode

    NASA Astrophysics Data System (ADS)

    Emirhan, E.; Bayrak, A.; Yücel, E. Barlas; Yücel, M.; Ozben, C. S.

    2016-05-01

    A low cost X-ray imaging device based on BPW-34 silicon PIN photodiode was designed and produced. X-rays were produced from a CEI OX/70-P dental tube using a custom made ±30 kV power supply. A charge sensitive preamplifier and a shaping amplifier were built for the amplification of small signals produced by photons in the depletion layer of Si-PIN photodiode. A two dimensional position control unit was used for moving the detector in small steps to measure the intensity of X-rays absorbed in the object to be imaged. An Aessent AES220B FPGA module was used for transferring the image data to a computer via USB. Images of various samples were obtained with acceptable image quality despite of the low cost of the device.

  10. Miniature Wireless BioSensor for Remote Endoscopic Monitoring

    NASA Astrophysics Data System (ADS)

    Nemiroski, Alex; Brown, Keith; Issadore, David; Westervelt, Robert; Thompson, Chris; Obstein, Keith; Laine, Michael

    2009-03-01

    We have built a miniature wireless biosensor with fluorescence detection capability that explores the miniaturization limit for a self-powered sensor device assembled from the latest off-the-shelf technology. The device is intended as a remote medical sensor to be inserted endoscopically and remainin a patient's gastrointestinal tract for a period of weeks, recording and transmitting data as necessary. A sensing network may be formed by using multiple such devices within the patient, routing information to an external receiver that communicates through existing mobilephone networks to relay data remotely. By using a monolithic IC chip with integrated processor, memory, and 2.4 GHz radio,combined with a photonic sensor and miniature battery, we have developed a fully functional computing device in a form factorcompliantwith insertion through the narrowest endoscopic channels (less than 3mm x 3mm x 20mm). We envision similar devices with various types of sensors to be used in many different areas of the human body.

  11. X ray sensitive area detection device

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor); Witherow, William K. (Inventor); Pusey, Marc L. (Inventor); Yost, Vaughn H. (Inventor)

    1990-01-01

    A radiation sensitive area detection device is disclosed which comprises a phosphor-containing film capable of receiving and storing an image formed by a pattern of incoming x rays, UV, or other radiation falling on the film. The device is capable of fluorescing in response to stimulation by a light source in a manner directly proportional to the stored radiation pattern. The device includes: (1) a light source capable of projecting light or other appropriate electromagnetic wave on the film so as to cause it to fluoresce; (2) a means to focus the fluoresced light coming from the phosphor-containing film after light stimulation; and (3) at least one charged coupled detector or other detecting element capable of receiving and digitizing the pattern of fluoresced light coming from the phosphor-containing film. The device will be able to generate superior x ray images of high resolution from a crystal or other sample and will be particularly advantageous in that instantaneous near-real-time images of rapidly deteriorating samples can be obtained. Furthermore, the device can be made compact and sturdy, thus capable of carrying out x ray or other radiation imaging under a variety of conditions, including those experienced in space.

  12. Upgrade of MacCHESS facility for X-ray scattering of biological macromolecules in solution

    PubMed Central

    Acerbo, Alvin Samuel; Cook, Michael J.; Gillilan, Richard Edward

    2015-01-01

    X-ray scattering of biological macromolecules in solution is an increasingly popular tool for structural biology and benefits greatly from modern high-brightness synchrotron sources. The upgraded MacCHESS BioSAXS station is now located at the 49-pole wiggler beamline G1. The 20-fold improved flux over the previous beamline F2 provides higher sample throughput and autonomous X-ray scattering data collection using a unique SAXS/WAXS dual detectors configuration. This setup achieves a combined q-range from 0.007 to 0.7 Å−1, enabling better characterization of smaller molecules, while opening opportunities for emerging wide-angle scattering methods. In addition, a facility upgrade of the positron storage ring to continuous top-up mode has improved beam stability and eliminated beam drift over the course of typical BioSAXS experiments. Single exposure times have been reduced to 2 s for 3.560 mg ml−1 lysozyme with an average quality factor I/σ of 20 in the Guinier region. A novel disposable plastic sample cell design that incorporates lower background X-ray window material provides users with a more pristine sample environment than previously available. Systematic comparisons of common X-ray window materials bonded to the cell have also been extended to the wide-angle regime, offering new insight into best choices for various q-space ranges. In addition, a quantitative assessment of signal-to-noise levels has been performed on the station to allow users to estimate necessary exposure times for obtaining usable signals in the Guinier regime. Users also have access to a new BioSAXS sample preparation laboratory which houses essential wet-chemistry equipment and biophysical instrumentation. User experiments at the upgraded BioSAXS station have been on-going since commissioning of the beamline in Summer 2013. A planned upgrade of the G1 insertion device to an undulator for the Winter 2014 cycle is expected to further improve flux by an order of magnitude. PMID:25537607

  13. Novel Chalcogenide Materials for x ray and Gamma ray Detection

    DTIC Science & Technology

    2016-05-01

    REPORT OF PROJECT: Novel chalcogenide materials for x - ray and - ray detection HDTRA1-09-1-0044 Mercouri Kanatzidis , PI Northwestern University...investigated semiconductor for hard radiation detection. The μτ products for electrons however are lower than those of CZT, the leading material for X - ray ...Formation of native defects in the gamma- ray detector material, Cs2Hg6S7 Semiconductor devices detecting hard radiation such as x - rays and

  14. Rise time measurement for ultrafast X-ray pulses

    DOEpatents

    Celliers, Peter M [Berkeley, CA; Weber, Franz A [Oakland, CA; Moon, Stephen J [Tracy, CA

    2005-04-05

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  15. Rise Time Measurement for Ultrafast X-Ray Pulses

    DOEpatents

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  16. Experimental Results and Modeling of Low-Heat-Capacity TES Microcalorimeters for Soft-X-ray Spectroscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eckart, Megan E.; NASA Postdoctoral Program Fellow; Adams, Joseph S.

    2009-12-16

    Transition-edge-sensor (TES) X-ray microcalorimeters have mostly been targeted at mid-band energies from 0.05-10 keV and high energies to above 100 keV. However, many other optimizations are possible. Here we present results from devices optimized for soft X-ray applications. For spectroscopy below 1 keV, the X-ray stopping power and heat capacity (C) of the TES itself are high enough that we can omit a separate absorber. The resulting devices have low C and the best-achievable energy resolution should be under 1 eV. We are interested in pursuing such devices primarily for astrophysical applications and laboratory astrophysics at LLNL's Electron-Beam Ion Trap.more » To this end, we have studied arrays in which 'bare' TESs are interspersed with broad-band pixels that have absorbers. By extending the absorbers to cover the area where the leads contact the low-energy pixels, we have eliminated a significant source of non-Gaussian detector response. The bare devices are in a different regime from our typical devices in that C is ten times lower and the conductance to the bath is four times lower. We have explored this regime through simultaneous fitting of noise and impedance data. These data cannot be fit by the simple model we employ to describe our typical broad-band devices. In this contribution we present X-ray spectra and the results from modeling.« less

  17. Investigation of Carbon Fiber Architecture in Braided Composites Using X-Ray CT Inspection

    NASA Technical Reports Server (NTRS)

    Rhoads, Daniel J.; Miller, Sandi G.; Roberts, Gary D.; Rauser, Richard W.; Golovaty, Dmitry; Wilber, J. Patrick; Espanol, Malena I.

    2017-01-01

    During the fabrication of braided carbon fiber composite materials, process variations occur which affect the fiber architecture. Quantitative measurements of local and global fiber architecture variations are needed to determine the potential effect of process variations on mechanical properties of the cured composite. Although non-destructive inspection via X-ray CT imaging is a promising approach, difficulties in quantitative analysis of the data arise due to the similar densities of the material constituents. In an effort to gain more quantitative information about features related to fiber architecture, methods have been explored to improve the details that can be captured by X-ray CT imaging. Metal-coated fibers and thin veils are used as inserts to extract detailed information about fiber orientations and inter-ply behavior from X-ray CT images.

  18. Probing the Li Insertion Mechanism of ZnFe 2O 4 in Li-Ion Batteries: A Combined X-Ray Diffraction, Extended X-Ray Absorption Fine Structure, and Density Functional Theory Study [Probing the Li insertion mechanism of ZnFe 2O 4 in Li ion batteries: A combined XRD, EXAFS, and DFT study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Yiman; Pelliccione, Christopher J.; Brady, Alexander B.

    Here, we report an extensive study on fundamental properties that determine the functional electrochemistry of ZnFe 2O 4 spinel (theoretical capacity of 1000 mAh/g). For the first time, the reduction mechanism is followed through a combination of in situ X-ray diffraction data, synchrotron based powder diffraction, and ex-situ extended X-ray absorption fine structure allowing complete visualization of reduction products irrespective of their crystallinity. The first 0.5 electron equivalents (ee) do not significantly change the starting crystal structure. Subsequent lithiation results in migration of Zn 2+ ions from 8a tetrahedral sites into vacant 16c sites. Density functional theory shows that Limore » + ions insert into 16c site initially and then 8a site with further lithiation. Fe metal is formed over the next eight ee of reduction with no evidence of concurrent Zn 2+ reduction to Zn metal. Despite the expected formation of LiZn alloy from the electron count, we find no evidence for this phase under the tested conditions. Additionally, upon oxidation to 3 V, we observe an FeO phase with no evidence of Fe 2O 3. Electrochemistry data show higher electron equivalent transfer than can be accounted for solely based on ZnFe 2O 4 reduction indicating excess capacity ascribed to carbon reduction or surface electrolyte interphase formation.« less

  19. Probing the Li Insertion Mechanism of ZnFe 2O 4 in Li-Ion Batteries: A Combined X-Ray Diffraction, Extended X-Ray Absorption Fine Structure, and Density Functional Theory Study [Probing the Li insertion mechanism of ZnFe 2O 4 in Li ion batteries: A combined XRD, EXAFS, and DFT study

    DOE PAGES

    Zhang, Yiman; Pelliccione, Christopher J.; Brady, Alexander B.; ...

    2017-04-24

    Here, we report an extensive study on fundamental properties that determine the functional electrochemistry of ZnFe 2O 4 spinel (theoretical capacity of 1000 mAh/g). For the first time, the reduction mechanism is followed through a combination of in situ X-ray diffraction data, synchrotron based powder diffraction, and ex-situ extended X-ray absorption fine structure allowing complete visualization of reduction products irrespective of their crystallinity. The first 0.5 electron equivalents (ee) do not significantly change the starting crystal structure. Subsequent lithiation results in migration of Zn 2+ ions from 8a tetrahedral sites into vacant 16c sites. Density functional theory shows that Limore » + ions insert into 16c site initially and then 8a site with further lithiation. Fe metal is formed over the next eight ee of reduction with no evidence of concurrent Zn 2+ reduction to Zn metal. Despite the expected formation of LiZn alloy from the electron count, we find no evidence for this phase under the tested conditions. Additionally, upon oxidation to 3 V, we observe an FeO phase with no evidence of Fe 2O 3. Electrochemistry data show higher electron equivalent transfer than can be accounted for solely based on ZnFe 2O 4 reduction indicating excess capacity ascribed to carbon reduction or surface electrolyte interphase formation.« less

  20. Tuning the Seebeck effect in C60-based hybrid thermoelectric devices through temperature-dependent surface polarization and thermally-modulated interface dipoles.

    PubMed

    Liu, Yuchun; Xu, Ling; Zhao, Chen; Shao, Ming; Hu, Bin

    2017-06-07

    Fullerene (C 60 ) is an important n-type organic semiconductor with high electron mobility and low thermal conductivity. In this work, we report the experimental results on the tunable Seebeck effect of C 60 hybrid thin-film devices by adopting different oxide layers. After inserting n-type high-dielectric constant titanium oxide (TiO x ) and zinc oxide (ZnO) layers, we observed a significantly enhanced n-type Seebeck effect in oxide/C 60 hybrid devices with Seebeck coefficients of -5.8 mV K -1 for TiO x /C 60 and -2.08 mV K -1 for ZnO/C 60 devices at 100 °C, compared with the value of -400 μV K -1 for the pristine C 60 device. However, when a p-type nickel oxide (NiO) layer is inserted, the C 60 hybrid devices show a p-type to n-type Seebeck effect transition when the temperature increases. The remarkable Seebeck effect and change in Seebeck coefficient in different oxide/C 60 hybrid devices can be attributed to two reasons: the temperature-dependent surface polarization difference and thermally-dependent interface dipoles. Firstly, the surface polarization difference due to temperature-dependent electron-phonon coupling can be enhanced by inserting an oxide layer and functions as an additional driving force for the Seebeck effect development. Secondly, thermally-dependent interface dipoles formed at the electrode/oxide interface play an important role in modifying the density of interface states and affecting the charge diffusion in hybrid devices. The surface polarization difference and interface dipoles function in the same direction in hybrid devices with TiO x and ZnO dielectric layers, leading to enhanced n-type Seebeck effect, while the surface polarization difference and interface dipoles generate the opposite impact on electron diffusion in ITO/NiO/C 60 /Al, leading to a p-type to n-type transition in the Seebeck effect. Therefore, inserting different oxide layers could effectively modulate the Seebeck effect of C 60 -based hybrid devices through the surface polarization difference and thermally-dependent interface dipoles, which represents an effective approach to tune the vertical Seebeck effect in organic functional devices.

  1. Generation of flash x-rays using a mercury-anode radiation tube

    NASA Astrophysics Data System (ADS)

    Oizumi, Teiji; Sato, Eiichi; Sagae, Michiaki; Hayasi, Yasuomi; Tamakawa, Yoshiharu; Yanagisawa, Toru

    1993-02-01

    The constructions and the radiographic characteristics of a flash x-ray generator having a liquid-anode radiation tube are described. This generator consisted of the following essential components: a high-voltage power supply, a combined ceramic condenser of 10.7 nF, an oil- diffusion pump, an oil circulator, a trigger device, and a flash x-ray tube. The x-ray tube was of a triode and was composed of the following major devices: a mercury anode, a rod-shaped graphite cathode, a trigger electrode made from a copper wire, an x-ray window made from a polyethyleneterephthalate film, and a glass tube body. The ceramic condenser was charged from 40 to 60 kV by a power supply, and the electric charges in the condenser were discharged to the x-ray tube after the triggering. The maximum tube voltage was equivalent to the initial charged voltage of the condenser, and the tube current was less than 0.7 kA. The pulse widths of the flash x rays had values of about 1 microsecond(s) , and the time-integrated x-ray intensity was about 2.4 (mu) C/kg at 0.26 m per pulse with a charged voltage of 60 kV.

  2. A radially accessible tubular in situ X-ray cell for spatially resolved operando scattering and spectroscopic studies of electrochemical energy storage devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Hao; Allan, Phoebe K.; Borkiewicz, Olaf J.

    2016-09-16

    A tubularoperandoelectrochemical cell has been developed to allow spatially resolved X-ray scattering and spectroscopic measurements of individual cell components, or regions thereof, during device operation. These measurements are enabled by the tubular cell geometry, wherein the X-ray-transparent tube walls allow radial access for the incident and scattered/transmitted X-ray beam; by probing different depths within the electrode stack, the transformation of different components or regions can be resolved. The cell is compatible with a variety of synchrotron-based scattering, absorption and imaging methodologies. The reliability of the electrochemical cell and the quality of the resulting X-ray scattering and spectroscopic data are demonstratedmore » for two types of energy storage: the evolution of the distribution of the state of charge of an Li-ion battery electrode during cycling is documented using X-ray powder diffraction, and the redistribution of ions between two porous carbon electrodes in an electrochemical double-layer capacitor is documented using X-ray absorption near-edge spectroscopy.« less

  3. Nitrogen soft and hard X-ray emissions using different shapes of anodes in a 4-kJ plasma focus device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mahtab, M., E-mail: m.mahtab.83@gmail.com; Habibi, M., E-mail: mortezahabibi@aut.ac.ir

    2013-12-15

    The effect of different anode tip geometries on the intensity of soft and hard X-rays emitted from a 4-kJ plasma focus device is investigated using five different anode tips. The shapes of the uppermost region of these anodes (tips) have been cylindrical-flat, cylindrical-hollow, spherical-convex, cone-flat, and cone-hollow. For time-resolved measurement of the emitted X-rays, several BPX-65 pin diodes covered by different filters and a fast plastic scintillator are used. Experimental results have shown that, the highest intensity of the both soft and hard X-ray is recorded in cone-flat, spherical-convex, and cone-hollow tips, respectively. The use of cone-flat anode tip hasmore » augmented the emitted X-ray three times.« less

  4. Two hump-shaped angular distributions of neutrons and soft X-rays in a small plasma focus device.

    PubMed

    Habibi, Morteza

    2018-03-01

    Angular distributions of soft X-rays (SXRs) and neutrons emitted by a small plasma focus device (PFD) were investigated simultaneously using TLD-100 dosimeters and Geiger-Muller activation counters, respectively. The distributions represented two humps with a small dip at the angular position 0° and reduced from the angles of ± 15° and ± 30° for the neutrons and SXRs, respectively. The maximum yield of 2.98 × 10 8 neutrons per shot of the device was obtained at 13.5kV and 6.5mbar. A time of flight (TOF) of 75.2ns between the hard X-ray and the neutron peaks corresponds to neutrons with energy of 2.67MeV. A similar behavior was observed between the angular distributions of neutron and soft X-ray emissions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. New National Air-Kerma Standard for Low-Energy Electronic Brachytherapy Sources

    PubMed Central

    Seltzer, Stephen M; O’Brien, Michelle; Mitch, Michael G

    2014-01-01

    The new primary standard for low-energy electronic brachytherapy sources for the United States is described. These miniature x-ray tubes are inserted in catheters for interstitial radiation therapy and operate at tube potentials of up to about 50 kV. The standard is based on the realization of the air kerma produced by the x-ray beam at a reference distance in air of 50 cm. PMID:26601044

  6. Ambient x-ray pollution assessment at inspection gates of airports- a case study of Mehrabad and Imam Khomeini Airports in Iran.

    PubMed

    Pourtaghi, Gholamhossein; Valipour, Firouz; Nourian, Sepideh; Mofidi, Amirabbas

    2014-01-01

    As a well-known, physical carcinogen, ambient X-ray pollution assessment would be of great importance in today's modern world. Accordingly, the present study was done to measure the exposure level of ambient X-ray at inspection gates of two airports in Iran. According to which, the X-ray was measured at different points of the inspection gates including closed and opened Curtain, as well as seating place of operators beside the X-ray inspection systems. The recorded data were then analyzed by "sign" and t-tests. The total average exposure level of the measured x-ray was 2.68 ± 0.73 μsv.h(-1). The measured x-ray exposure level was 2.07 ± 0.61 (μsv.h(-1)) released from RAPISCAN X-ray inspection system and 3.3 ± 1.34 (μsv.h(-1)) emitted from HEIMANN X-ray inspection system. Comparison of average x-ray doses of the systems in both airports showed that the minimum and maximum exposure levels were recorded at 1(m) far from the devices and at the entrance of the devices, respectively. The exposure levels at all measurement points were lower than the occupational exposure limit. This reveals the fact that the exposed operators are not probably at risk of adverse health effects.

  7. Industrial Inspection System

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Lixi, Inc. has built a thriving business on NASA-developed x-ray technology. The Low Intensity X-ray Imaging scope (LIXI) was designed to use less than one percent of radiation required by conventional x-ray devices. It is portable and can be used for a variety of industrial inspection systems as well as medical devices. A food processing plant uses the new LIXI Conveyor system to identify small bone fragments in chicken. The chicken packages on a conveyor belt enter an x-ray chamber and the image is displayed on a monitor. Defects measuring less than a millimeter can be detected. An important advantage of the system is its ability to inspect 100 percent of the product right on the production line.

  8. Automatic tool alignment in a backscatter X-ray scanning system

    DOEpatents

    Garretson, Justin; Hobart, Clinton G.; Gladwell, Thomas S.; Monda, Mark J.

    2015-11-17

    Technologies pertaining to backscatter x-ray scanning systems are described herein. The backscatter x-ray scanning system includes an x-ray source, which directs collimated x-rays along a plurality of output vectors towards a target. A detector detects diffusely reflected x-rays subsequent to respective collimated x-rays impacting the target, and outputs signals indicative of parameters of the detected x-rays. An image processing system generates an x-ray image based upon parameters of the detected x-rays, wherein each pixel in the image corresponds to a respective output vector. A user selects a particular portion of the image, and a medical device is positioned such that its directional axis is coincident with the output vector corresponding to at least one pixel in the portion of the image.

  9. Direct X-ray photoconversion in flexible organic thin film devices operated below 1 V

    PubMed Central

    Basiricò, Laura; Ciavatti, Andrea; Cramer, Tobias; Cosseddu, Piero; Bonfiglio, Annalisa; Fraboni, Beatrice

    2016-01-01

    The application of organic electronic materials for the detection of ionizing radiations is very appealing thanks to their mechanical flexibility, low-cost and simple processing in comparison to their inorganic counterpart. In this work we investigate the direct X-ray photoconversion process in organic thin film photoconductors. The devices are realized by drop casting solution-processed bis-(triisopropylsilylethynyl)pentacene (TIPS-pentacene) onto flexible plastic substrates patterned with metal electrodes; they exhibit a strong sensitivity to X-rays despite the low X-ray photon absorption typical of low-Z organic materials. We propose a model, based on the accumulation of photogenerated charges and photoconductive gain, able to describe the magnitude as well as the dynamics of the X-ray-induced photocurrent. This finding allows us to fabricate and test a flexible 2 × 2 pixelated X-ray detector operating at 0.2 V, with gain and sensitivity up to 4.7 × 104 and 77,000 nC mGy−1 cm−3, respectively. PMID:27708274

  10. Spectral structure of a polycapillary lens shaped X-ray beam

    NASA Astrophysics Data System (ADS)

    Gogolev, A. S.; Filatov, N. A.; Uglov, S. R.; Hampai, D.; Dabagov, S. B.

    2018-04-01

    Polycapillary X-ray optics is widely used in X-ray analysis techniques to create a small secondary source, for instance, or to deliver X-rays to the point of interest with minimum intensity losses [1]. The main characteristics of the analytical devices on its base are the size and divergence of the focused or translated beam. In this work, we used the photon-counting pixel detector ModuPIX to study the parameters for polycapillary focused X-ray tube radiation as well as the energy and spatial dependences of radiation at the focus. We have characterized the high-speed spectral camera ModuPIX, which is a single Timepix device with a fast parallel readout allowing up to 850 frames per second with 256 × 256 pixels and a 55 μm pitch defined by the frame frequency. By means of the silicon monochromator the energy response function is measured in clustering mode by the energy scan over total X-ray tube spectrum.

  11. A 5- μ m pitch charge-coupled device optimized for resonant inelastic soft X-ray scattering

    DOE PAGES

    Andresen, N. C.; Denes, P.; Goldschmidt, A.; ...

    2017-08-08

    Here, we have developed a charge-coupled device (CCD) with 5 μm × 45 μm pixels on high-resistivity silicon. The fully depleted 200 μm-thick silicon detector is back-illuminated through a 10 nm-thick in situ doped polysilicon window and is thus highly efficient for soft through > 8 keV hard X-rays. The device described here is a 1.5 megapixel CCD with 2496 × 620 pixels. The pixel and camera geometry was optimized for Resonant Inelastic X-ray Scattering (RIXS) and is particularly advantageous for spectrometers with limited arm lengths. In this article, we describe the device architecture, construction and operation, and its performancemore » during tests at the Advance Light Source (ALS) 8.0.1 RIXS beamline. The improved spectroscopic performance, when compared with a current standard commercial camera, is demonstrated with a ~280 eV (C K) X-ray beam on a graphite sample. Readout noise is typically 3-6 electrons and the point spread function for soft C K X-rays in the 5 μm direction is 4.0 μm ± 0.2 μm. Finally, the measured quantum efficiency of the CCD is greater than 75% in the range from 200 eV to 1 keV.« less

  12. A 5-μm pitch charge-coupled device optimized for resonant inelastic soft X-ray scattering

    NASA Astrophysics Data System (ADS)

    Andresen, N. C.; Denes, P.; Goldschmidt, A.; Joseph, J.; Karcher, A.; Tindall, C. S.

    2017-08-01

    We have developed a charge-coupled device (CCD) with 5 μm × 45 μm pixels on high-resistivity silicon. The fully depleted 200 μm-thick silicon detector is back-illuminated through a 10 nm-thick in situ doped polysilicon window and is thus highly efficient for soft through >8 keV hard X-rays. The device described here is a 1.5 megapixel CCD with 2496 × 620 pixels. The pixel and camera geometry was optimized for Resonant Inelastic X-ray Scattering (RIXS) and is particularly advantageous for spectrometers with limited arm lengths. In this article, we describe the device architecture, construction and operation, and its performance during tests at the Advance Light Source (ALS) 8.0.1 RIXS beamline. The improved spectroscopic performance, when compared with a current standard commercial camera, is demonstrated with a ˜280 eV (CK) X-ray beam on a graphite sample. Readout noise is typically 3-6 electrons and the point spread function for soft CK X-rays in the 5 μm direction is 4.0 μm ± 0.2 μm. The measured quantum efficiency of the CCD is greater than 75% in the range from 200 eV to 1 keV.

  13. A 5-μm pitch charge-coupled device optimized for resonant inelastic soft X-ray scattering.

    PubMed

    Andresen, N C; Denes, P; Goldschmidt, A; Joseph, J; Karcher, A; Tindall, C S

    2017-08-01

    We have developed a charge-coupled device (CCD) with 5 μm × 45 μm pixels on high-resistivity silicon. The fully depleted 200 μm-thick silicon detector is back-illuminated through a 10 nm-thick in situ doped polysilicon window and is thus highly efficient for soft through >8 keV hard X-rays. The device described here is a 1.5 megapixel CCD with 2496 × 620 pixels. The pixel and camera geometry was optimized for Resonant Inelastic X-ray Scattering (RIXS) and is particularly advantageous for spectrometers with limited arm lengths. In this article, we describe the device architecture, construction and operation, and its performance during tests at the Advance Light Source (ALS) 8.0.1 RIXS beamline. The improved spectroscopic performance, when compared with a current standard commercial camera, is demonstrated with a ∼280 eV (C K ) X-ray beam on a graphite sample. Readout noise is typically 3-6 electrons and the point spread function for soft C K X-rays in the 5 μm direction is 4.0 μm ± 0.2 μm. The measured quantum efficiency of the CCD is greater than 75% in the range from 200 eV to 1 keV.

  14. Scanning electron microscopy, x-ray diffraction, and electron microprobe analysis of calcific deposits on intrauterine contraceptive devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khan, S.R.; Wilkinson, E.J.

    Deposits found on intrauterine contraceptive devices (IUDs) were studied by scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray microanalysis. All seven devices, including five plastic and two copper IUDs, were coated with a crust containing cellular, acellular, and fibrillar material. The cellular material was composed of erythrocytes, leukocytes, cells of epithelial origin, sperm, and bacteria. Some of the bacteria were filamentous, with acute-angle branching. The fibrillar material appeared to be fibrin. Most of the acellular material was amorphous; calcite was identified by x-ray diffraction, and x-ray microanalysis showed only calcium. Some of the acellular material, particularly that on themore » IUD side of the crust, was organized in spherulitic crystals and was identified as calcium phosphate by x-ray microanalysis. The crust was joined to the IUD surface by a layer of fibrillar and amorphous material. It is suggested that the initial event in the formation of calcific deposits on IUD surfaces is the deposition of an amorphous and fibrillar layer. Various types of cells present in the endometrial environment adhere to this layer and then calcify. Thus, the deposition of calcific material on the IUDs is a calcification phenomenon, not unlike the formation of plaque on teeth.« less

  15. Small, Fast TES Microcalorimeters with Unprecedented X-ray Spectral Performance

    NASA Technical Reports Server (NTRS)

    Eckart, M. E.; Adams, J. S.; Bailey, C. N.; Bandler, S. R.; Chervenak, J. A.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.; Sadleir, J. E.; hide

    2011-01-01

    Driven initially by the desire for X-ray microcalorimeter arrays suitable for imaging the dynamic solar corona, we have developed a transition-edge-sensor (TES) microcalorimeter optimization that exhibits a unique combination of high spectral resolving power and a wide X-ray bandpass. These devices have achieved spectral performance of dE approximately 1.3 eV FWHM at 1.5 keV, 1.6 eV at 6 keV, and 2.0 eV at 8 keV, using small TESs (e.g., approximately 35 micron x 35 micron) that operate in a regime in which the superconducting transition is highly current dependent. In order to accommodate high X-ray count rates, the devices sit directly on a solid substrate instead of on membranes, and we use an embedded heatsinking layer to reduce pixel-to-pixel crosstalk. We will present results from devices with a range of TES and absorber sizes, and from device wafers with varied embedded heatsink materials. This contribution will focus on count-rate capabilities, including a discussion of the trade-off between count rate and energy resolution, and the heatsinking design. We will also present preliminary tests of array readout using a code-division multiplexed SQUID readout scheme, which may be necessary to enable large arrays of these fast devices.

  16. Dose inspection and risk assessment on radiation safety for the use of non-medical X-ray machines in Taiwan

    NASA Astrophysics Data System (ADS)

    Hsu, Fang-Yuh; Hsu, Shih-Ming; Chao, Jiunn-Hsing

    2017-11-01

    The subject of this study is the on-site visits and inspections of facilities commissioned by the Atomic Energy Council (AEC) in Taiwan. This research was conducted to evaluate the possible dose and dose rate of cabinet-type X-ray equipment with nominal voltages of 30-150 kV and open-beam (portable or handheld) equipment, taking both normal operation and possibly abnormal operation conditions into account. Doses and dose rates were measured using a plastic scintillation survey meter and an electronic personal dosimeter. In total, 401 X-ray machines were inspected, including 139 units with nominal voltages of 30-50 kV X-ray equipment, 140 units with nominal voltages of 50-150 kV, and 122 open-beam (portable or handheld) X-ray equipment. The investigated doses for radiation workers and non-radiation workers operating cabinet-type X-ray equipment under normal safety conditions were all at the background dose level. Several investigated dose rates at the position of 10 cm away from the surface of open-beam (portable or handheld) X-ray equipment were very high, such X-ray machines are used by aeronautical police for the detection of suspected explosives, radiation workers are far away (at least 10 m away) from the X-ray machine during its operation. The doses per operation in X-ray equipment with a 30-50 kV nominal voltage were less than 1 mSv in all cases of abnormal use. Some doses were higher than 1 mSv per operation for X-ray equipment of 50-150 kV nominal voltage X-ray. The maximum dose rates at the beam exit have a very wide range, mostly less than 100 μSv/s and the largest value is about 3.92 mSv/s for open-beam (portable or handheld) X-ray devices. The risk induced by operating X-ray devices with nominal voltages of 30-50 kV is extremely low. The 11.5 mSv dose due to one operation at nominal voltage of 50-150 kV X-ray device is equivalent to the exposure of taking 575 chest X-rays. In the abnormal use of open-beam (portable or handheld) X-ray equipment, the effective dose of 3.92 mSv/s is equivalent to taking 196 chest radiographs within 1 s. This work assessed the annual doses (equivalent and effective doses) and risks of X-ray operator staff as reasonably as possible. The results of this research are helpful to the AEC (competent authority of ionization radiation) to improve the management and perform the safe control of X-ray equipment.

  17. Pump–probe spectrometer for measuring x-ray induced strain

    DOE PAGES

    Loether, A.; Adams, B. W.; DiCharia, A.; ...

    2016-04-20

    A hard x-ray pump–probe spectrometer using a multi-crystal Bragg reflector is demonstrated at a third generation synchrotron source. This device derives both broadband pump and monochromatic probe pulses directly from a single intense, broadband x-ray pulse centered at 8.767 keV. In conclusion, we present a proof-of-concept experiment which directly measures x-ray induced crystalline lattice strain.

  18. The insertional torque of a pedicle screw has a positive correlation with bone mineral density in posterior lumbar pedicle screw fixation.

    PubMed

    Lee, J H; Lee, J-H; Park, J W; Shin, Y H

    2012-01-01

    In patients with osteoporosis there is always a strong possibility that pedicle screws will loosen. This makes it difficult to select the appropriate osteoporotic patient for a spinal fusion. The purpose of this study was to determine the correlation between bone mineral density (BMD) and the magnitude of torque required to insert a pedicle screw. To accomplish this, 181 patients with degenerative disease of the lumbar spine were studied prospectively. Each underwent dual-energy x-ray absorptiometry (DEXA) and intra-operative measurement of the torque required to insert each pedicle screw. The levels of torque generated in patients with osteoporosis and osteopenia were significantly lower than those achieved in normal patients. Positive correlations were observed between BMD and T-value at the instrumented lumbar vertebrae, mean BMD and mean T-value of the lumbar vertebrae, and mean BMD and mean T-value of the proximal femur. The predictive torque (Nm) generated during pedicle screw insertion was [-0.127 + 1.62 × (BMD at the corresponding lumbar vertebrae)], as measured by linear regression analysis. The positive correlation between BMD and the maximum torque required to insert a pedicle screw suggests that pre-operative assessment of BMD may be useful in determining the ultimate strength of fixation of a device, as well as the number of levels that need to be fixed with pedicle screws in patients who are suspected of having osteoporosis.

  19. Performance and Characterization of Magnetic Penetration Thermometer Devices for X-Ray Spectroscopy

    NASA Technical Reports Server (NTRS)

    Porst, J. -P.; Adams, J. S.; Bandler, S. R.; Balvin, M.; Busch, S. E.; Denis, K. L.; Kelly, D.; Nagler, P.; Sadleir, J. E.; Seidel, G. M.; hide

    2012-01-01

    We are developing magnetic penetration thermometers (MPTs) for applications in X-ray astronomy. These non-dissipative devices consist of an X-ray absorber in good thermal contact to a superconducting thin film with a transition temperature around T=100mK. A microfabricated superconducting planar inductor underneath is used to store a persistent current and couple the superconductor's diamagnetic response to a readout SQUID. The strong temperature dependence of the diamagnetic response make these devices suitable for highly sensitive macroscopic thermometers that are capable of achieving very high energy resolution. We present results achieved with MPTs consisting of MoAu bilayer sensors attached to overhanging square 250 micron by 250 micron gold absorbers that have demonstrated an energy resolution of delta E_FWHM=2.3eV at an X-ray energy of 5.9keV. A similar device has shown delta E_FWHM=2.0eV at 1.5 keV. Under certain conditions and for specific device geometries, the temperature responsivity of the MPTs can vary on long timescales degrading the spectral performance. We present the characterization of different inductor geometries to optimize the design for the highest possible temperature sensitivity and compare different device designs with respect to responsivity stability.

  20. Geometry calibration for x-ray equipment in radiation treatment devices and estimation of remaining patient alignment errors

    NASA Astrophysics Data System (ADS)

    Selby, Boris P.; Sakas, Georgios; Walter, Stefan; Stilla, Uwe

    2008-03-01

    Positioning a patient accurately in treatment devices is crucial for radiological treatment, especially if accuracy vantages of particle beam treatment are exploited. To avoid sub-millimeter misalignments, X-ray images acquired from within the device are compared to a CT to compute respective alignment corrections. Unfortunately, deviations of the underlying geometry model for the imaging system degrade the achievable accuracy. We propose an automatic calibration routine, which bases on the geometry of a phantom and its automatic detection in digital radiographs acquired for various geometric device settings during the calibration. The results from the registration of the phantom's X-ray projections and its known geometry are used to update the model of the respective beamlines, which is used to compute the patient alignment correction. The geometric calibration of a beamline takes all nine relevant degrees of freedom into account, including detector translations in three directions, detector tilt by three axes and three possible translations for the X-ray tube. Introducing a stochastic model for the calibration we are able to predict the patient alignment deviations resulting from inaccuracies inherent to the phantom design and the calibration. Comparisons of the alignment results for a treatment device without calibrated imaging systems and a calibrated device show that an accurate calibration can enhance alignment accuracy.

  1. Reviewed approach to defining the Active Interlock Envelope for Front End ray tracing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seletskiy, S.; Shaftan, T.

    To protect the NSLS-II Storage Ring (SR) components from damage from synchrotron radiation produced by insertion devices (IDs) the Active Interlock (AI) keeps electron beam within some safe envelope (a.k.a Active Interlock Envelope or AIE) in the transverse phase space. The beamline Front Ends (FEs) are designed under assumption that above certain beam current (typically 2 mA) the ID synchrotron radiation (IDSR) fan is produced by the interlocked e-beam. These assumptions also define how the ray tracing for FE is done. To simplify the FE ray tracing for typical uncanted ID it was decided to provide the Mechanical Engineering groupmore » with a single set of numbers (x,x’,y,y’) for the AIE at the center of the long (or short) ID straight section. Such unified approach to the design of the beamline Front Ends will accelerate the design process and save valuable human resources. In this paper we describe our new approach to defining the AI envelope and provide the resulting numbers required for design of the typical Front End.« less

  2. Imaging radiation detector with gain

    DOEpatents

    Morris, C.L.; Idzorek, G.C.; Atencio, L.G.

    1982-07-21

    A radiation imaging device which has application in x-ray imaging. The device can be utilized in CAT scanners and other devices which require high sensitivity and low x-ray fluxes. The device utilizes cumulative multiplication of charge carriers on the anode plane and the collection of positive ion charges to image the radiation intensity on the cathode plane. Parallel and orthogonal cathode wire arrays are disclosed as well as a two-dimensional grid pattern for collecting the positive ions on the cathode.

  3. Imaging radiation detector with gain

    DOEpatents

    Morris, Christopher L.; Idzorek, George C.; Atencio, Leroy G.

    1984-01-01

    A radiation imaging device which has application in x-ray imaging. The device can be utilized in CAT scanners and other devices which require high sensitivity and low x-ray fluxes. The device utilizes cumulative multiplication of charge carriers on the anode plane and the collection of positive ion charges to image the radiation intensity on the cathode plane. Parallel and orthogonal cathode wire arrays are disclosed as well as a two-dimensional grid pattern for collecting the positive ions on the cathode.

  4. Noncontacting devices to indicate deflection and vibration of turbopump internal rotating parts

    NASA Technical Reports Server (NTRS)

    Hamilton, D. B.; Ensminger, D.; Grieser, D. R.; Plummer, A. M.; Saccocio, E. J.; Kissel, J. W.

    1973-01-01

    The research is reported which was conducted to develop devices for measuring vibrations and deflections of parts, such as impellers, shafts, turbine wheels, and inducers in operating turbopumps. Three devices were developed to the breadboard stage: ultrasonic Doppler transducer, flash X-rays, and light-pipe reflectance. It was found that the X-ray technique is applicable to the shaft assembly and the turbine seal of the J-2 pump, and the light-pipe-reflectance device appears to be ideal for cryogenic pump sections.

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

    PubMed

    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.

  6. Large enhancement of Blocking temperature by control of interfacial structures in Pt/NiFe/IrMn/MgO/Pt multilayers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Xi; Wang, Shouguo, E-mail: sgwang@ustb.edu.cn; Han, Gang

    2015-09-15

    The Blocking temperature (T{sub B}) of Pt/NiFe/IrMn/MgO/Pt multilayers was greatly enhanced from far below room temperature (RT) to above RT by inserting 1 nm thick Mg layer at IrMn/MgO interface. Furthermore, the exchange bias field (H{sub eb}) was increased as well by the control of interfacial structures. The evidence for a significant fraction of Mn-O bonding at IrMn/MgO interface without Mg insertion layer was provided by X-ray photoelectron spectroscopy. The bonding between Mn and O can decrease the antiferromagnetism of IrMn film, leading to lower value of T{sub B} in Pt/NiFe/IrMn/MgO/Pt multilayers. Ultrathin Mg film inserted at IrMn/MgO interface actingmore » as an oxygen sinking layer can suppress the oxidation reactions between Mn and O and reduce the formation of Mn-O bonding greatly. The oxidation suppression results in the recovery of the antiferromagnetism of IrMn film, which can enhance T{sub B} and H{sub eb}. Furthermore, the high resolution transmission electron microscopy demonstrates that the Mg insertion layer can efficiently promote a high-quality MgO (200) texture. This study will enhance the understanding of physics in antiferromagnet-based spintronic devices.« less

  7. Recent X-ray hybrid CMOS detector developments and measurements

    NASA Astrophysics Data System (ADS)

    Hull, Samuel V.; Falcone, Abraham D.; Burrows, David N.; Wages, Mitchell; Chattopadhyay, Tanmoy; McQuaide, Maria; Bray, Evan; Kern, Matthew

    2017-08-01

    The Penn State X-ray detector lab, in collaboration with Teledyne Imaging Sensors (TIS), have progressed their efforts to improve soft X-ray Hybrid CMOS detector (HCD) technology on multiple fronts. Having newly acquired a Teledyne cryogenic SIDECARTM ASIC for use with HxRG devices, measurements were performed with an H2RG HCD and the cooled SIDECARTM. We report new energy resolution and read noise measurements, which show a significant improvement over room temperature SIDECARTM operation. Further, in order to meet the demands of future high-throughput and high spatial resolution X-ray observatories, detectors with fast readout and small pixel sizes are being developed. We report on characteristics of new X-ray HCDs with 12.5 micron pitch that include in-pixel CDS circuitry and crosstalk-eliminating CTIA amplifiers. In addition, PSU and TIS are developing a new large-scale array Speedster-EXD device. The original 64 × 64 pixel Speedster-EXD prototype used comparators in each pixel to enable event driven readout with order of magnitude higher effective readout rates, which will now be implemented in a 550 × 550 pixel device. Finally, the detector lab is involved in a sounding rocket mission that is slated to fly in 2018 with an off-plane reflection grating array and an H2RG X-ray HCD. We report on the planned detector configuration for this mission, which will increase the NASA technology readiness level of X-ray HCDs to TRL 9.

  8. Suite of three protein crystallography beamlines with single superconducting bend magnet as the source.

    PubMed

    MacDowell, Alastair A; Celestre, Rich S; Howells, Malcolm; McKinney, Wayne; Krupnick, James; Cambie, Daniella; Domning, Edward E; Duarte, Robert M; Kelez, Nicholas; Plate, David W; Cork, Carl W; Earnest, Thomas N; Dickert, Jeffery; Meigs, George; Ralston, Corie; Holton, James M; Alber, Tom; Berger, James M; Agard, David A; Padmore, Howard A

    2004-11-01

    At the Advanced Light Source, three protein crystallography beamlines have been built that use as a source one of the three 6 T single-pole superconducting bending magnets (superbends) that were recently installed in the ring. The use of such single-pole superconducting bend magnets enables the development of a hard X-ray program on a relatively low-energy 1.9 GeV ring without taking up insertion-device straight sections. The source is of relatively low power but, owing to the small electron beam emittance, it has high brightness. X-ray optics are required to preserve the brightness and to match the illumination requirements for protein crystallography. This was achieved by means of a collimating premirror bent to a plane parabola, a double-crystal monochromator followed by a toroidal mirror that focuses in the horizontal direction with a 2:1 demagnification. This optical arrangement partially balances aberrations from the collimating and toroidal mirrors such that a tight focused spot size is achieved. The optical properties of the beamline are an excellent match to those required by the small protein crystals that are typically measured. The design and performance of these new beamlines are described.

  9. Commissioning of the soft x-ray undulator beamline at the Siam Photon Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nakajima, Hideki, E-mail: hideki@slri.or.th; Chaichuay, Sarunyu; Sudmuang, Porntip

    2016-07-27

    The synchrotron radiation from the first undulator at the Siam Photon Laboratory was characterized with the photon beam position monitors (BPMs) and grating monochromator. The soft x-ray undulator beamline employs a varied line-spacing plane grating monochromator with three interchangeable gratings. Since 2010, the beamline has delivered photons with energy of 40-160 and 220-1040 eV at the resolving power of 10,000 for user services at the two end- stations that utilize the photoemission electron spectroscopy and microscopy techniques. The undulator power-density distributions measured by the 0.05-mm wire-scan BPM were in good agreement with those in simulation. The flux-density distributions were evaluatedmore » in the red-shift measurements, which identify the central cone of radiation and its distribution. Since 2014, the operation of the other insertion devices in the storage ring has started, and consequently bought about the increases in the emittance from 41 to 61 nm·rad and the coupling constant from 4 to 11%. The local electron-orbit correction greatly improved the alignment of the electron beam in the undulator section resulting in the improvements of the photon flux and harmonics peaks of the undulator radiation.« less

  10. TiO2 as diffusion barrier at Co/Alq3 interface studied by x-ray standing wave technique

    NASA Astrophysics Data System (ADS)

    Phatak Londhe, Vaishali; Gupta, A.; Ponpandian, N.; Kumar, D.; Reddy, V. R.

    2018-06-01

    Nano-scale diffusion at the interfaces in organic spin valve thin films plays a vital role in controlling the performance of magneto-electronic devices. In the present work, it is shown that a thin layer of titanium dioxide at the interface of Co/Alq3 can act as a good diffusion barrier. The buried interfaces of Co/Alq3/Co organic spin valve thin film has been studied using x-ray standing waves technique. A planar waveguide is formed with Alq3 layer forming the cavity and Co layers as the walls of the waveguide. Precise information about diffusion of Co into Alq3 is obtained through excitation of the waveguide modes. It is found that the top Co layer diffuses deep into the Alq3 resulting in incorporation of 3.1% Co in the Alq3 layer. Insertion of a 1.7 nm thick barrier layer of TiO2 at Co/Alq3 interface results in a drastic reduction in the diffusion of Co into Alq3 to a value of only 0.4%. This suggests a better performance of organic spin valve with diffusion barrier of TiO2.

  11. Multi-Absorber Transition-Edge Sensors for X-Ray Astronomy Applications

    NASA Technical Reports Server (NTRS)

    Smith, S. J.; Adams, J. S.; Bandler, S. R.; Busch, S. E.; Chervenak, J. A.; Eckart, M. E.; Ewin, A. J.; Finkbeiner, F. M.; Kelley, R. L.; Kelly, D. P.; hide

    2012-01-01

    We are developing multi-absorber Transition-Edge Sensors (TESs) for applications in x-ray astronomy. These position-sensitive devices consist of multiple x-ray absorbers each with a different thermal coupling to a single readout TES. Heat diffusion between the absorbers and the TES gives rise to a characteristic pulse shape corresponding to each absorber element and enables position discrimination. The development of these detectors is motivated by a desire to maximize focal plane arrays with the fewest number of readout channels. In this contribution we report on the first results from devices consisting of nine) 65 X 65 sq. microns Au x-ray absorbers) 5 microns thick. These are coupled to a single 35 X 35 sq. microns Mo/Au bilayer TES. These devices have demonstrated full-width-half-maximum (FWHM) energy resolution of 2.1 eV at 1.5 keV) 2.5 eV at 5.9 keV and 3.3 eV at 8 keV. This is coupled with position discrimination from pulse shape over the same energy range. We use a finite-element model to reproduce the measured pulse shapes and investigate the detector non-linearity with energy) which impacts on the devices position sensitivity and energy resolution.

  12. X-Pinch And Its Applications In X-ray Radiograph

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zou Xiaobing; Wang Xinxin; Liu Rui

    2009-07-07

    An X-pinch device and the related diagnostics of x-ray emission from X-pinch were briefly described. The time-resolved x-ray measurements with photoconducting diodes show that the x-ray pulse usually consists of two subnanosecond peaks with a time interval of about 0.5 ns. Being consistent with these two peaks of the x-ray pulse, two point x-ray sources of size ranging from 100 mum to 5 mum and depending on cut-off x-ray photon energy were usually observed on the pinhole pictures. The x-pinch was used as x-ray source for backlighting of the electrical explosion of single wire and the evolution of X-pinch, andmore » for phase-contrast imaging of soft biological objects such as a small shrimp and a mosquito.« less

  13. The Lixiscope: a Pocket-size X-ray Imaging System

    NASA Technical Reports Server (NTRS)

    Yin, L. I.; Seltzer, S. M.

    1978-01-01

    A Low Intensity X ray Imaging device with the acronym LIXISCOPE is described. The Lixiscope has a small format and is powered only by a 2.7V battery. The high inherent gain of the Lixiscope permits the use of radioactive sources in lieu of X-ray machines in some fluoroscopic applications. In this mode of operation the complete X ray imaging system is truly portable and pocket-sized.

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

    NASA Astrophysics Data System (ADS)

    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).

  15. Ambient x-ray pollution assessment at inspection gates of airports- a case study of Mehrabad and Imam Khomeini Airports in Iran

    PubMed Central

    2014-01-01

    Background As a well-known, physical carcinogen, ambient X-ray pollution assessment would be of great importance in today’s modern world. Accordingly, the present study was done to measure the exposure level of ambient X-ray at inspection gates of two airports in Iran. According to which, the X-ray was measured at different points of the inspection gates including closed and opened Curtain, as well as seating place of operators beside the X-ray inspection systems. The recorded data were then analyzed by “sign” and t-tests. Results The total average exposure level of the measured x-ray was 2.68 ± 0.73 μsv.h-1. The measured x-ray exposure level was 2.07 ± 0.61 (μsv.h-1) released from RAPISCAN X-ray inspection system and 3.3 ± 1.34 (μsv.h-1) emitted from HEIMANN X-ray inspection system. Comparison of average x-ray doses of the systems in both airports showed that the minimum and maximum exposure levels were recorded at 1(m) far from the devices and at the entrance of the devices, respectively. Conclusions The exposure levels at all measurement points were lower than the occupational exposure limit. This reveals the fact that the exposed operators are not probably at risk of adverse health effects. PMID:24955243

  16. Data Collection and Recording on the Wisconsin/GSFC X-ray Quantum Calorimeter

    NASA Astrophysics Data System (ADS)

    O'Neill, Laura; X-ray Astrophysics Group at the University of Wisconsin-Madison

    2016-01-01

    The Wisconsin/GSFC X-ray Quantum Calorimeter (XQC) is an astronomical X-ray sounding rocket payload which uses a micro-calorimeter array to detect low (less than1keV) X-rays. Three different devices were evaluated to upgrade XQC's data collection and recording system. The system takes incoming data from XQC's pixel sensors and stores it to a memory card. The upgrade is a much smaller board and much more compact storage device. The Terasic DE0-Nano, Terasic DE0-Nano SoC, and the BeagleBone Black were tested to determine which would suit the needs of XQC best. The device needed to take incoming data, store it to an SD card, and be able to output it through a USB connection. The Terasic DE0-Nano is a simple FPGA, but needed some peripheral additions for an SD card slot and USB readout. The Terasic DE0-Nano SoC was a powerful FPGA and hard processor running Linux combined. It was able to do what was needed, but pulled too much power in the process. The BeagleBone Black had a microcontroller and also ran Linux. This last device ended up being the best choice, as it did not require too much power and had a very easy system already in place for USB readout. The only difficulty to deal with was programming the microcontroller in assembly language. This device is necessary due to the telemetry on XQC not being able to send all of the data down during the flight. It records valuable data about low energy X-rays so that the X-ray Astrophysics Groups at the University of Wisconsin-Madison and Goddard Space Flight Center can analyze and resolve the spectrum of the soft X-ray background.Later, using the digital logic on a Terasic DE0-Nano FPGA, a data simulator for the BeagleBone Black data collection and recording device was created. Programmed with Quartus II, the simulator uses basic digital logic components to fabricate trackable data signals and related timing signals to send to the data management device, as well as other timing signals that are asynchronous to the rest of the circuit, a failsafe enable for outputs, and several user feedback components

  17. 3D localization of electrophysiology catheters from a single x-ray cone-beam projection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robert, Normand, E-mail: normand.robert@sri.utoronto.ca; Polack, George G.; Sethi, Benu

    2015-10-15

    Purpose: X-ray images allow the visualization of percutaneous devices such as catheters in real time but inherently lack depth information. The provision of 3D localization of these devices from cone beam x-ray projections would be advantageous for interventions such as electrophysiology (EP), whereby the operator needs to return a device to the same anatomical locations during the procedure. A method to achieve real-time 3D single view localization (SVL) of an object of known geometry from a single x-ray image is presented. SVL exploits the change in the magnification of an object as its distance from the x-ray source is varied.more » The x-ray projection of an object of interest is compared to a synthetic x-ray projection of a model of said object as its pose is varied. Methods: SVL was tested with a 3 mm spherical marker and an electrophysiology catheter. The effect of x-ray acquisition parameters on SVL was investigated. An independent reference localization method was developed to compare results when imaging a catheter translated via a computer controlled three-axes stage. SVL was also performed on clinical fluoroscopy image sequences. A commercial navigation system was used in some clinical image sequences for comparison. Results: SVL estimates exhibited little change as x-ray acquisition parameters were varied. The reproducibility of catheter position estimates in phantoms denoted by the standard deviations, (σ{sub x}, σ{sub y}, σ{sub z}) = (0.099 mm,  0.093 mm,  2.2 mm), where x and y are parallel to the detector plane and z is the distance from the x-ray source. Position estimates (x, y, z) exhibited a 4% systematic error (underestimation) when compared to the reference method. The authors demonstrated that EP catheters can be tracked in clinical fluoroscopic images. Conclusions: It has been shown that EP catheters can be localized in real time in phantoms and clinical images at fluoroscopic exposure rates. Further work is required to characterize performance in clinical images as well as the sensitivity to clinical image quality.« less

  18. X-ray angiography systems.

    PubMed

    1993-11-01

    Despite the emergence of several alternative angiographic imaging techniques (i.e., magnetic resonance imaging, computed tomography, and ultrasound angiography), x-ray angiography remains the predominant vascular imaging modality, generating over $4 billion in revenue a year in U.S. hospitals. In this issue, we provide a brief overview of the various angiographic imaging techniques, comparing them with x-ray angiography, and discuss the clinical aspects of x-ray vascular imaging, including catheterization and clinical applications. Clinical, cost, usage, and legal issues related to contrast media are discussed in "Contrast Media: Ionic versus Nonionic and Low-osmolality Agents." We also provide a technical overview and selection guidance for a basic x-ray angiography imaging system, including the gantry and table system, x-ray generator, x-ray tube, image intensifier, video camera and display monitors, image-recording devices, and digital acquisition and processing systems. This issue also contains our Evaluation of the GE Advantx L/C cardiac angiography system and the GE Advantx AFM general-purpose angiography system; the AFM can be used for peripheral, pulmonary, and cerebral vascular studied, among others, and can also be configured for cardiac angiography. Many features of the Advantx L/C system, including generator characteristics and ease of use, also apply to the Advantx AFM as configured for cardiac angiography. Our ratings are based on the systems' ability to provide the best possible image quality for diagnosis and therapy while minimizing patient and personnel exposure to radiation, as well as its ability to minimize operator effort and inconvenience. Both units are rated Acceptable. In the Guidance Section, "Radiation Safety and Protection," we discuss the importance of keeping patient and personnel exposures to radiation as low as reasonably possible, especially in procedures such as cardiac catheterization, angiographic imaging for special procedures, and interventional radiology, which produce among the highest radiation exposure of all x-ray imaging techniques. We also provide recommendations for minimizing personnel and patient exposures to radiation. For more information about x-ray angiography systems and similar devices, as well as for additional perspectives on which we based this study, see the following Health Devices Evaluations: "Mobile C-arm Units" (19[8], August 1990) and "Noninvasive Electronic Quality Control Devices for X-ray Generator Testing" (21[6-7], June-July 1992).(ABSTRACT TRUNCATED AT 400 WORDS)

  19. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    DOE PAGES

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; ...

    2015-08-11

    Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called `fixed-target' sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessarymore » to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. In addition, the features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.« less

  20. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.

    Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called `fixed-target' sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessarymore » to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. In addition, the features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.« less

  1. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.

    Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called `fixed-target' sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary tomore » fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15µm) loaded into the chips yielded a complete, high-resolution (<1.6Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.« less

  2. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    PubMed Central

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; Vo, Huy; Uervirojnangkoorn, Monarin; Brunger, Axel T.; Berger, James M.

    2015-01-01

    Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs. PMID:26457423

  3. Image quality assessment and medical physics evaluation of different portable dental X-ray units.

    PubMed

    Pittayapat, Pisha; Oliveira-Santos, Christiano; Thevissen, Patrick; Michielsen, Koen; Bergans, Niki; Willems, Guy; Debruyckere, Deborah; Jacobs, Reinhilde

    2010-09-10

    Recently developed portable dental X-ray units increase the mobility of the forensic odontologists and allow more efficient X-ray work in a disaster field, especially when used in combination with digital sensors. This type of machines might also have potential for application in remote areas, military and humanitarian missions, dental care of patients with mobility limitation, as well as imaging in operating rooms. To evaluate radiographic image quality acquired by three portable X-ray devices in combination with four image receptors and to evaluate their medical physics parameters. Images of five samples consisting of four teeth and one formalin-fixed mandible were acquired by one conventional wall-mounted X-ray unit, MinRay 60/70 kVp, used as a clinical standard, and three portable dental X-ray devices: AnyRay 60 kVp, Nomad 60 kVp and Rextar 70 kVp, in combination with a phosphor image plate (PSP), a CCD, or a CMOS sensor. Three observers evaluated images for standard image quality besides forensic diagnostic quality on a 4-point rating scale. Furthermore, all machines underwent tests for occupational as well as patient dosimetry. Statistical analysis showed good quality imaging for all system, with the combination of Nomad and PSP yielding the best score. A significant difference in image quality between the combination of the four X-ray devices and four sensors was established (p<0.05). For patient safety, the exposure rate was determined and exit dose rates for MinRay at 60 kVp, MinRay at 70 kVp, AnyRay, Nomad and Rextar were 3.4 mGy/s, 4.5 mGy/s, 13.5 mGy/s, 3.8 mGy/s and 2.6 mGy/s respectively. The kVp of the AnyRay system was the most stable, with a ripple of 3.7%. Short-term variations in the tube output of all the devices were less than 10%. AnyRay presented higher estimated effective dose than other machines. Occupational dosimetry showed doses at the operator's hand being lowest with protective shielding (Nomad: 0.1 microGy). It was also low while using remote control (distance>1m: Rextar <0.2 microGy, MinRay <0.1 microGy). The present study demonstrated the feasibility of three portable X-ray systems to be used for specific indications, based on acceptable image quality and sufficient accuracy of the machines and following the standard guidelines for radiation hygiene. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  4. An undulator based soft x-ray source for microscopy on the Duke electron storage ring

    NASA Astrophysics Data System (ADS)

    Johnson, Lewis Elgin

    1998-09-01

    This dissertation describes the design, development, and installation of an undulator-based soft x-ray source on the Duke Free Electron Laser laboratory electron storage ring. Insertion device and soft x-ray beamline physics and technology are all discussed in detail. The Duke/NIST undulator is a 3.64-m long hybrid design constructed by the Brobeck Division of Maxwell Laboratories. Originally built for an FEL project at the National Institute of Standards and Technology, the undulator was acquired by Duke in 1992 for use as a soft x-ray source for the FEL laboratory. Initial Hall probe measurements on the magnetic field distribution of the undulator revealed field errors of more than 0.80%. Initial phase errors for the device were more than 11 degrees. Through a series of in situ and off-line measurements and modifications we have re-tuned the magnet field structure of the device to produce strong spectral characteristics through the 5th harmonic. A low operating K has served to reduce the effects of magnetic field errors on the harmonic spectral content. Although rms field errors remained at 0.75%, we succeeded in reducing phase errors to less than 5 degrees. Using trajectory simulations from magnetic field data, we have computed the spectral output given the interaction of the Duke storage ring electron beam and the NIST undulator. Driven by a series of concerns and constraints over maximum utility, personnel safety and funding, we have also constructed a unique front end beamline for the undulator. The front end has been designed for maximum throughput of the 1st harmonic around 40A in its standard mode of operation. The front end has an alternative mode of operation which transmits the 3rd and 5th harmonics. This compact system also allows for the extraction of some of the bend magnet produced synchrotron and transition radiation from the storage ring. As with any well designed front end system, it also provides excellent protection to personnel and to the storage ring. A diagnostic beamline consisting of a transmission grating spectrometer and scanning wire beam profile monitor was constructed to measure the spatial and spectral characteristics of the undulator radiation. Test of the system with a circulating electron beam has confirmed the magnetic and focusing properties of the undulator, and verified that it can be used without perturbing the orbit of the beam.

  5. Barium enema (image)

    MedlinePlus

    A barium enema is performed to examine the walls of the colon. During the procedure, a well lubricated enema tube is inserted gently into the rectum. The barium, a radiopaque (shows up on X-ray) contrast ...

  6. Monochromatic X-ray-induced thermal effect on four-reflection “nested” meV-monochromators: dynamical diffraction theory and finite-element analysis

    NASA Astrophysics Data System (ADS)

    Hu, Ling-Fei; Gao, Li-Dan; Li, Zhen-Jie; Wang, Shan-Feng; Sheng, Wei-Fan; Liu, Peng; Xu, Wei

    2015-09-01

    The high energy resolution monochromator (HRM) is widely used in inelastic scattering programs to detect phonons with energy resolution, down to the meV level. Although the large amount of heat from insertion devices can be reduced by a high heat-load monochromator, the unbalanced heat load on the inner pair of crystals in a nested HRM can affect its overall performance. Here, a theoretical analysis of the unbalanced heat load using dynamical diffraction theory and finite element analysis is presented. By utilizing the ray-tracing method, the performance of different HRM nesting configurations is simulated. It is suggested that the heat balance ratio, energy resolution, and overall spectral transmission efficiency are the figures of merit for evaluating the performance of nested HRMs. Although the present study is mainly focused on nested HRMs working at 57Fe nuclear resonant energy at 14.4 keV, it is feasible to extend this to other nested HRMs working at different energies.

  7. 21 CFR 1020.30 - Diagnostic x-ray systems and their major components.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... irradiation. Diagnostic source assembly means the tube housing assembly with a beam-limiting device attached. Diagnostic x-ray system means an x-ray system designed for irradiation of any part of the human body for the... diagnostic source assembly. Fluoroscopic irradiation time means the cumulative duration during an examination...

  8. 21 CFR 1020.30 - Diagnostic x-ray systems and their major components.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... irradiation. Diagnostic source assembly means the tube housing assembly with a beam-limiting device attached. Diagnostic x-ray system means an x-ray system designed for irradiation of any part of the human body for the... diagnostic source assembly. Fluoroscopic irradiation time means the cumulative duration during an examination...

  9. 21 CFR 1020.30 - Diagnostic x-ray systems and their major components.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... irradiation. Diagnostic source assembly means the tube housing assembly with a beam-limiting device attached. Diagnostic x-ray system means an x-ray system designed for irradiation of any part of the human body for the... diagnostic source assembly. Fluoroscopic irradiation time means the cumulative duration during an examination...

  10. Polarization control in an X-ray free-electron laser

    DOE PAGES

    Lutman, Alberto A.; MacArthur, James P.; Ilchen, Markus; ...

    2016-05-09

    X-ray free-electron lasers are unique sources of high-brightness coherent radiation. However, existing devices supply only linearly polarized light, precluding studies of chiral dynamics. A device called the Delta undulator has been installed at the Linac Coherent Light Source (LCLS) to provide tunable polarization. With a reverse tapered planar undulator line to pre-microbunch the beam and the novel technique of beam diverting, hundreds of microjoules of circularly polarized X-ray pulses are produced at 500–1,200 eV. These X-ray pulses are tens of femtoseconds long, have a degree of circular polarization of 0.98 –0.04 +0.02 at 707 eV and may be scanned inmore » energy. We also present a new two-colour X-ray pump–X-ray probe operating mode for the LCLS. As a result, energy differences of ΔE/E = 2.4% are supported, and the second pulse can be adjusted to any elliptical polarization. In this mode, the pointing, timing, intensity and wavelength of the two pulses can be modified.« less

  11. Overview of nanoscale NEXAFS performed with soft X-ray microscopes.

    PubMed

    Guttmann, Peter; Bittencourt, Carla

    2015-01-01

    Today, in material science nanoscale structures are becoming more and more important. Not only for the further miniaturization of semiconductor devices like carbon nanotube based transistors, but also for newly developed efficient energy storage devices, gas sensors or catalytic systems nanoscale and functionalized materials have to be analysed. Therefore, analytical tools like near-edge X-ray absorption fine structure (NEXAFS) spectroscopy has to be applied on single nanostructures. Scanning transmission X-ray microscopes (STXM) as well as full-field transmission X-ray microscopes (TXM) allow the required spatial resolution to study individual nanostructures. In the soft X-ray energy range only STXM was used so far for NEXAFS studies. Due to its unique setup, the TXM operated by the Helmholtz-Zentrum Berlin (HZB) at the electron storage ring BESSY II is the first one in the soft X-ray range which can be used for NEXAFS spectroscopy studies which will be shown in this review. Here we will give an overview of the different microscopes used for NEXAFS studies and describe their advantages and disadvantages for different samples.

  12. Shift focal spot X-ray tube to the imposition anode under long exposure

    NASA Astrophysics Data System (ADS)

    Obodovskiy, A. V.; Bessonov, V. B.; Larionov, I. A.

    2018-02-01

    X-ray non-destructive testing is an integral part of any modern industrial production. Microfocus X-ray sources make it possible to obtain projected images with an increased spatial resolution by using a direct geometric magnification during the survey. On the basis of the St. Petersburg State Electrotechnical University staff of the department of electronic devices and equipment has been designed model of microfocus X-ray computed tomography.

  13. Insertion of Guest Molecules into a Mixed Ligand Metal-Organic Framework via Single-Crystal-to-Single Crystal Guest Exchange

    DTIC Science & Technology

    2014-07-01

    powder x-ray diffraction (PXRD), thermogravimentric analysis (TGA), and Fourier transform infrared (FTIR). 15. SUBJECT TERMS Metal organic frame work...the inclusion by using a variety of analytical techniques, such as powder x-ray diffraction (PXRD), thermo-gravimetric analysis (TGA), Fourier...Characterizations Analysis of the MOF and the complexes with the MOF and the guest molecules was performed using an Agilent GC-MS (Model 6890N GC and Model 5973N

  14. X-ray appearance of subcutaneous gemstones as part of alternative/holistic medicine: a case report and review of the literature.

    PubMed

    McLemore, Jerri; Hallengren, Aaron L

    2010-01-01

    The authors present a case of a deceased man with numerous subcutaneous nodules identified as foreign bodies on radiographic films. The foreign bodies were gemstones inserted underneath the skin as a form of holistic medicine. The X-ray findings of this case and a review of the literature for similar subcutaneously implanted foreign bodies used in holistic, alternative, or folk medicine are presented. Copyright 2010 Elsevier Inc. All rights reserved.

  15. High count-rate study of two TES x-ray microcalorimeters with different transition temperatures

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Jun; Adams, Joseph S.; Bandler, Simon R.; Betancourt-Martinez, Gabriele L.; Chervenak, James A.; Eckart, Megan E.; Finkbeiner, Fred M.; Kelley, Richard L.; Kilbourne, Caroline A.; Porter, Frederick S.; Sadleir, John E.; Smith, Stephen J.; Wassell, Edward J.

    2017-10-01

    We have developed transition-edge sensor (TES) microcalorimeter arrays with high count-rate capability and high energy resolution to carry out x-ray imaging spectroscopy observations of various astronomical sources and the Sun. We have studied the dependence of the energy resolution and throughput (fraction of processed pulses) on the count rate for such microcalorimeters with two different transition temperatures (T c). Devices with both transition temperatures were fabricated within a single microcalorimeter array directly on top of a solid substrate where the thermal conductance of the microcalorimeter is dependent upon the thermal boundary resistance between the TES sensor and the dielectric substrate beneath. Because the thermal boundary resistance is highly temperature dependent, the two types of device with different T cs had very different thermal decay times, approximately one order of magnitude different. In our earlier report, we achieved energy resolutions of 1.6 and 2.3 eV at 6 keV from lower and higher T c devices, respectively, using a standard analysis method based on optimal filtering in the low flux limit. We have now measured the same devices at elevated x-ray fluxes ranging from 50 Hz to 1000 Hz per pixel. In the high flux limit, however, the standard optimal filtering scheme nearly breaks down because of x-ray pile-up. To achieve the highest possible energy resolution for a fixed throughput, we have developed an analysis scheme based on the so-called event grade method. Using the new analysis scheme, we achieved 5.0 eV FWHM with 96% throughput for 6 keV x-rays of 1025 Hz per pixel with the higher T c (faster) device, and 5.8 eV FWHM with 97% throughput with the lower T c (slower) device at 722 Hz.

  16. Comparison of two portable solid state detectors with an improved collimation and alignment device for mammographic x-ray spectroscopy.

    PubMed

    Bottigli, U; Golosio, B; Masala, G L; Oliva, P; Stumbo, S; Delogu, P; Fantacci, M E; Abbene, L; Fauci, F; Raso, G

    2006-09-01

    We describe a portable system for mammographic x-ray spectroscopy, based on a 2 X 2 X 1 mm3 cadmium telluride (CdTe) solid state detector, that is greatly improved over a similar system based on a 3 X 3 X 2 mm3 cadmium zinc telluride (CZT) solid state detector evaluated in an earlier work. The CdTe system utilized new pinhole collimators and an alignment device that facilitated measurement of mammographic x-ray spectra. Mammographic x-ray spectra acquired by each system were comparable. Half value layer measurements obtained using an ion chamber agreed closely with those derived from the x-ray spectra measured by either detector. The faster electronics and other features of the CdTe detector allowed its use with a larger pinhole collimator than could be used with the CZT detector. Additionally, the improved pinhole collimator and alignment features of the apparatus permitted much more rapid setup for acquisition of x-ray spectra than was possible on the system described in the earlier work. These improvements in detector technology, collimation and ease of alignment, as well as low cost, make this apparatus attractive as a tool for both laboratory research and advanced mammography quality control.

  17. A backing device based on an embedded stiffener and retractable insertion tool for thin-film cochlear arrays

    NASA Astrophysics Data System (ADS)

    Tewari, Radheshyam

    Intracochlear trauma from surgical insertion of bulky electrode arrays and inadequate pitch perception are areas of concern with current hand-assembled commercial cochlear implants. Parylene thin-film arrays with higher electrode densities and lower profiles are a potential solution, but lack rigidity and hence depend on manually fabricated permanently attached polyethylene terephthalate (PET) tubing based bulky backing devices. As a solution, we investigated a new backing device with two sub-systems. The first sub-system is a thin poly(lactic acid) (PLA) stiffener that will be embedded in the parylene array. The second sub-system is an attaching and detaching mechanism, utilizing a poly(N-vinylpyrrolidone)-block-poly(d,l-lactide) (PVP-b-PDLLA) copolymer-based biodegradable and water soluble adhesive, that will help to retract the PET insertion tool after implantation. As a proof-of-concept of sub-system one, a microfabrication process for patterning PLA stiffeners embedded in parylene has been developed. Conventional hot-embossing, mechanical micromachining, and standard cleanroom processes were integrated for patterning fully released and discrete stiffeners coated with parylene. The released embedded stiffeners were thermoformed to demonstrate that imparting perimodiolar shapes to stiffener-embedded arrays will be possible. The developed process when integrated with the array fabrication process will allow fabrication of stiffener-embedded arrays in a single process. As a proof-of-concept of sub-system two, the feasibility of the attaching and detaching mechanism was demonstrated by adhering 1x and 1.5x scale PET tube-based insertion tools and PLA stiffeners embedded in parylene using the copolymer adhesive. The attached devices survived qualitative adhesion tests, thermoforming, and flexing. The viability of the detaching mechanism was tested by aging the assemblies in-vitro in phosphate buffer solution. The average detachment times, 2.6 minutes and 10 minutes for 1x and 1.5x scale devices respectively, were found to be clinically relevant with respect to the reported array insertion times during surgical implantation. Eventually, the stiffener-embedded arrays would not need to be permanently attached to current insertion tools which are left behind after implantation and congest the cochlear scala tympani chamber. Finally, a simulation-based approach for accelerated failure analysis of PLA stiffeners and characterization of PVP-b-PDLLA copolymer adhesive has been explored. The residual functional life of embedded PLA stiffeners exposed to body-fluid and thereby subjected to degradation and erosion has been estimated by simulating PLA stiffeners with different parylene coating failure types and different PLA types for a given parylene coating failure type. For characterizing the PVP-b-PDLLA copolymer adhesive, several formulations of the copolymer adhesive were simulated and compared based on the insertion tool detachment times that were predicted from the dissolution, degradation, and erosion behavior of the simulated adhesive formulations. Results indicate that the simulation-based approaches could be used to reduce the total number of time consuming and expensive in-vitro tests that must be conducted.

  18. Laparoscopic management of a translocated intrauterine device embedded in the gastric serosa.

    PubMed

    Bozkurt, Murat; Yumru, Ayse Ender; Coskun, Ebru Inci; Ondes, Banu

    2011-10-01

    Intrauterine devices (IUD) are the most common contraceptive methods all over the world. Besides many advantages, there are also some complications of this method. The most important complication of IUD is uterine perforation. The reported incidence of IUD perforation ranges from 0.2 to 9.6 per thousand insertions. In this article we would like to report a case that has an IUD migrated to the gastric serosa. A 41 years-old Turkish woman presented with abdominal pain. Plain X-ray of the abdomen demonstrated two IUDs, one in the upper quadrant of the abdomen, the other in the pelvic area and determined in the endometrium by TV-USG (transvaginal ultrasonography). Laparascopy was performed and the IUD, lying over the omentum of stomach was removed. This report demonstrates the first case in the literature that has an IUD embedded in the gastric serosa and also a second IUD in uterine cavity. The management was performed laparoscopically. No complication was observed during and after operation.

  19. APPARATUS FOR PRODUCING SHADOWGRAPHS

    DOEpatents

    Wilson, R.R.

    1959-08-11

    An apparatus is presented for obtaining shadowgraphs or radiographs of an object exposed to x rays or the like. The device includes the combination of a cloud chamber having the interior illuminated and a portion thereof transparent to light rays and x'rays, a controlled source of x rays spaced therefrom, photographic recording disposed laterally of the linear path intermediate the source and the chamber portion in oblique angularity in aspect to the path. The object to be studied is disposed intermediate the x-ray source and chamber in the linear path to provide an x-ray transmission barrier therebetween. The shadowgraph is produced in the cloud chamber in response to initiation of the x- ray source and recorded photographically.

  20. Implementation of an electromagnetic imaging system to facilitate nasogastric and post-pyloric feeding tube placement in patients with and without critical illness.

    PubMed

    Windle, E M; Beddow, D; Hall, E; Wright, J; Sundar, N

    2010-02-01

    Artificial nutrition support is required to optimise nutritional status in many patients. Traditional methods of placing feeding tubes may incur clinical risk and financial costs. A technique facilitating placement of nasogastric and post-pyloric tubes via electromagnetic visual guidance may reduce the need for X-ray exposure, endoscopy time and the use of parenteral nutrition. The present study aimed to audit use of such a system at initial implementation in patients within an acute NHS Trust. A retrospective review was undertaken of dietetic and medical records for the first 14 months of using the Cortrak system. Data were collected on referral origin, preparation of the patient prior to insertion, placement success rates and need for X-ray. Cost analysis was also performed. Referrals were received from primary consultants or consultant intensivists, often on the advice of the dietitian. Fifty-nine percent of patients received prokinetic therapy at the time of placement. Thirty-nine tube placements were attempted. Sixty-nine percent of referrals for post-pyloric tube placement resulted in successful placement. X-ray films were requested for 22% of all attempted post-pyloric placements. Less than half of nasogastric tubes were successfully passed, although none of these required X-ray confirmation. The mean cost per tube insertion attempt was 111 pounds. This system confers advantages, particularly in terms of post-pyloric tube placement, even at this early stage of implementation. A reduction in clinical risk and cost avoidance related to X-ray exposure, the need for endoscopic tube placement and parenteral nutrition have been achieved. The implementation of this system should be considered in other centres.

  1. 21 CFR 1020.40 - Cabinet x-ray systems.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... intended to prevent the generation of x radiation when access by any part of the human body to the interior... the floor of the system. (3) Ports and apertures. (i) The insertion of any part of the human body... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...

  2. 21 CFR 1020.40 - Cabinet x-ray systems.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... intended to prevent the generation of x radiation when access by any part of the human body to the interior... the floor of the system. (3) Ports and apertures. (i) The insertion of any part of the human body... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...

  3. Telescope for x ray and gamma ray studies in astrophysics

    NASA Technical Reports Server (NTRS)

    Weaver, W. D.; Desai, Upendra D.

    1993-01-01

    Imaging of x-rays has been achieved by various methods in astrophysics, nuclear physics, medicine, and material science. A new method for imaging x-ray and gamma-ray sources avoids the limitations of previously used imaging devices. Images are formed in optical wavelengths by using mirrors or lenses to reflect and refract the incoming photons. High energy x-ray and gamma-ray photons cannot be reflected except at grazing angles and pass through lenses without being refracted. Therefore, different methods must be used to image x-ray and gamma-ray sources. Techniques using total absorption, or shadow casting, can provide images in x-rays and gamma-rays. This new method uses a coder made of a pair of Fresnel zone plates and a detector consisting of a matrix of CsI scintillators and photodiodes. The Fresnel zone plates produce Moire patterns when illuminated by an off-axis source. These Moire patterns are deconvolved using a stepped sine wave fitting or an inverse Fourier transform. This type of coder provides the capability of an instantaneous image with sub-arcminute resolution while using a detector with only a coarse position-sensitivity. A matrix of the CsI/photodiode detector elements provides the necessary coarse position-sensitivity. The CsI/photodiode detector also allows good energy resolution. This imaging system provides advantages over previously used imaging devices in both performance and efficiency.

  4. Digital Mammography with a Mosaic of CCD-Arrays

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); McAdoo, James A. (Inventor)

    1996-01-01

    The present invention relates generally to a mammography device and method and more particularly to a novel digital mammography device and method to detect microcalcifications of precancerous tissue. A digital mammography device uses a mosaic of electronic digital imaging arrays to scan an x-ray image. The mosaic of arrays is repositioned several times to expose different portions of the image, until the entire image is scanned. The data generated by the arrays during each exposure is stored in a computer. After the final exposure, the computer combines data of the several partial images to produce a composite of the original x-ray image. An aperture plate is used to reduce scatter and the overall exposure of the patient to x-rays. The novelty of this invention is that it provides a digital mammography device with large field coverage, high spatial resolution, scatter rejection, excellent contrast characteristics and lesion detectability under clinical conditions. This device also shields the patient from excessive radiation, can detect extremely small calcifications and allows manipulation and storage of the image.

  5. Microwave properties of epitaxial (111)-oriented Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} thin films on Al{sub 2}O{sub 3}(0001) up to 40 GHz

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang Lihui; UMR CNRS 8520, IEMN-DOAE-MIMM Team, Bat. P3, Cite Scientifique, Villeneuve d'Ascq, 59655 Lille; Ponchel, Freddy

    2010-10-18

    Perovskite Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} (BST) thin films have been grown on Al{sub 2}O{sub 3}(0001) substrates without/with inserting an ultrathin TiO{sub x} seeding layer by rf magnetron sputtering. X-ray diffraction and pole figure studies reveal that the film with the TiO{sub x} layer (12-A-thick) is highly oriented along the (111) direction and exhibits a good in-plane relationship of BST(111)||Al{sub 2}O{sub 3}(0001). The high frequency dielectric measurements demonstrate that the complex permittivity ({epsilon}={epsilon}{sup '}-j{epsilon}{sup ''}) is well described by a Curie-von Scheidler dispersion with an exponent of 0.40. The resulting epitaxial BST films show high permittivity ({approx}428) and tunability ({approx}41%, atmore » 300 kV/cm and 40 GHz) and their microwave properties (1-40 GHz) potentially could be made suitable for tunable devices.« less

  6. Extreme mobility enhancement of two-dimensional electron gases at oxide interfaces by charge-transfer-induced modulation doping

    NASA Astrophysics Data System (ADS)

    Chen, Y. Z.; Trier, F.; Wijnands, T.; Green, R. J.; Gauquelin, N.; Egoavil, R.; Christensen, D. V.; Koster, G.; Huijben, M.; Bovet, N.; Macke, S.; He, F.; Sutarto, R.; Andersen, N. H.; Sulpizio, J. A.; Honig, M.; Prawiroatmodjo, G. E. D. K.; Jespersen, T. S.; Linderoth, S.; Ilani, S.; Verbeeck, J.; van Tendeloo, G.; Rijnders, G.; Sawatzky, G. A.; Pryds, N.

    2015-08-01

    Two-dimensional electron gases (2DEGs) formed at the interface of insulating complex oxides promise the development of all-oxide electronic devices. These 2DEGs involve many-body interactions that give rise to a variety of physical phenomena such as superconductivity, magnetism, tunable metal-insulator transitions and phase separation. Increasing the mobility of the 2DEG, however, remains a major challenge. Here, we show that the electron mobility is enhanced by more than two orders of magnitude by inserting a single-unit-cell insulating layer of polar La1-xSrxMnO3 (x = 0, 1/8, and 1/3) at the interface between disordered LaAlO3 and crystalline SrTiO3 produced at room temperature. Resonant X-ray spectroscopy and transmission electron microscopy show that the manganite layer undergoes unambiguous electronic reconstruction, leading to modulation doping of such atomically engineered complex oxide heterointerfaces. At low temperatures, the modulation-doped 2DEG exhibits Shubnikov-de Haas oscillations and fingerprints of the quantum Hall effect, demonstrating unprecedented high mobility and low electron density.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Loether, A.; Adams, B. W.; DiCharia, A.

    A hard x-ray pump–probe spectrometer using a multi-crystal Bragg reflector is demonstrated at a third generation synchrotron source. This device derives both broadband pump and monochromatic probe pulses directly from a single intense, broadband x-ray pulse centered at 8.767 keV. In conclusion, we present a proof-of-concept experiment which directly measures x-ray induced crystalline lattice strain.

  8. Monolithic CMOS imaging x-ray spectrometers

    NASA Astrophysics Data System (ADS)

    Kenter, Almus; Kraft, Ralph; Gauron, Thomas; Murray, Stephen S.

    2014-07-01

    The Smithsonian Astrophysical Observatory (SAO) in collaboration with SRI/Sarnoff is developing monolithic CMOS detectors optimized for x-ray astronomy. The goal of this multi-year program is to produce CMOS x-ray imaging spectrometers that are Fano noise limited over the 0.1-10keV energy band while incorporating the many benefits of CMOS technology. These benefits include: low power consumption, radiation "hardness", high levels of integration, and very high read rates. Small format test devices from a previous wafer fabrication run (2011-2012) have recently been back-thinned and tested for response below 1keV. These devices perform as expected in regards to dark current, read noise, spectral response and Quantum Efficiency (QE). We demonstrate that running these devices at rates ~> 1Mpix/second eliminates the need for cooling as shot noise from any dark current is greatly mitigated. The test devices were fabricated on 15μm, high resistivity custom (~30kΩ-cm) epitaxial silicon and have a 16 by 192 pixel format. They incorporate 16μm pitch, 6 Transistor Pinned Photo Diode (6TPPD) pixels which have ~40μV/electron sensitivity and a highly parallel analog CDS signal chain. Newer, improved, lower noise detectors have just been fabricated (October 2013). These new detectors are fabricated on 9μm epitaxial silicon and have a 1k by 1k format. They incorporate similar 16μm pitch, 6TPPD pixels but have ~ 50% higher sensitivity and much (3×) lower read noise. These new detectors have undergone preliminary testing for functionality in Front Illuminated (FI) form and are presently being prepared for back thinning and packaging. Monolithic CMOS devices such as these, would be ideal candidate detectors for the focal planes of Solar, planetary and other space-borne x-ray astronomy missions. The high through-put, low noise and excellent low energy response, provide high dynamic range and good time resolution; bright, time varying x-ray features could be temporally and spectrally resolved without saturation. We present details of our camera design and device performance with particular emphasis on those aspects of interest to single photon counting x-ray astronomy. These features include read noise, x-ray spectral response and quantum efficiency. Funding for this work has been provided in large part by NASA Grant NNX09AE86G and a grant from the Betty and Gordon Moore Foundation.

  9. Diamond x-ray optics: Transparent, resilient, high-resolution, and wavefront preserving

    DOE PAGES

    Shvyd’ko, Yuri; Blank, Vladimir; Terentyev, Sergey

    2017-06-09

    Diamond features a unique combination of outstanding physical properties perfect for numerous x-ray optics applications, where traditional materials such as silicon fail to perform. In the last two decades, impressive progress has been achieved in synthesizing diamond with high crystalline perfection, in manufacturing efficient, resilient, high-resolution, wavefront-preserving diamond optical components, and in implementing them in cutting-edge x-ray instruments. Diamond optics are essential for tailoring x-rays to the most challenging needs of x-ray research. Furthermore, they are becoming vital for the generation of fully coherent hard x-rays by seeded x-ray free-electron lasers. In this article, we review progress in manufacturing flawlessmore » diamond crystal components and their applications in diverse x-ray optical devices, such as x-ray monochromators, beam splitters, high-reflectance backscattering mirrors, lenses, phase plates, diffraction gratings, bent-crystal spectrographs, and windows.« less

  10. Real-Time MRI-Guided Endovascular Recanalization of Chronic Total Arterial Occlusion in a Swine Model

    PubMed Central

    Raval, Amish N.; Karmarkar, Parag V.; Guttman, Michael A.; Ozturk, Cengizhan; Sampath, Smita; DeSilva, Ranil; Aviles, Ronnier J.; Xu, Minnan; Wright, Victor J.; Schenke, William H.; Kocaturk, Ozgur; Dick, Alexander J.; Raman, Venkatesh K.; Atalar, Ergin; McVeigh, Elliot R.; Lederman, Robert J.

    2006-01-01

    Background Endovascular recanalization (guidewire traversal) of peripheral artery chronic total occlusion (CTO) can be challenging. X-Ray angiography resolves CTO poorly. Virtually “blind” device advancement during X-ray-guided interventions can lead to procedure failure, perforation and hemorrhage. Alternatively, magnetic resonance imaging (MRI) may delineate the artery within the occluded segment to enhance procedural safety and success. We hypothesized that real-time MRI (rtMRI) guided CTO recanalization can be accomplished in an animal model. Methods and Results Carotid artery CTO was created by balloon injury in 19 lipid overfed swine. After 6–8 weeks, two underwent direct necropsy analysis for histology, three underwent primary X-ray-guided CTO recanalization attempts, and the remaining 14 underwent rtMRI-guided recanalization attempts in a 1.5T interventional MRI system. rtMRI intervention used custom CTO catheters and guidewires that incorporated MRI receiver antennae to enhance device visibility. The mean length of the occluded segments was 13.3 ± 1.6cm. rtMRI-guided CTO recanalization was successful in 11/14 swine and only 1/3 swine using X-ray alone. After unsuccessful rtMRI (n = 3), X-ray-guided attempts also were all unsuccessful. Conclusions Recanalization of long CTO is feasible entirely using rtMRI guidance. Low profile clinical-grade devices will be required to translate this experience to humans. Endovascular recanalization of chronic total arterial occlusion (CTO) is challenging under conventional X-ray guidance because devices are advanced almost blindly. MRI can image CTO borders and luminal contents, and could potentially guide these procedures. We test the feasibility of real-time MRI guided wire traversal in a swine model of peripheral artery CTO using custom active MRI catheters. PMID:16490819

  11. Dual mode stereotactic localization method and application

    DOEpatents

    Keppel, Cynthia E.; Barbosa, Fernando Jorge; Majewski, Stanislaw

    2002-01-01

    The invention described herein combines the structural digital X-ray image provided by conventional stereotactic core biopsy instruments with the additional functional metabolic gamma imaging obtained with a dedicated compact gamma imaging mini-camera. Before the procedure, the patient is injected with an appropriate radiopharmaceutical. The radiopharmaceutical uptake distribution within the breast under compression in a conventional examination table expressed by the intensity of gamma emissions is obtained for comparison (co-registration) with the digital mammography (X-ray) image. This dual modality mode of operation greatly increases the functionality of existing stereotactic biopsy devices by yielding a much smaller number of false positives than would be produced using X-ray images alone. The ability to obtain both the X-ray mammographic image and the nuclear-based medicine gamma image using a single device is made possible largely through the use of a novel, small and movable gamma imaging camera that permits its incorporation into the same table or system as that currently utilized to obtain X-ray based mammographic images for localization of lesions.

  12. A large format membrane-based x-ray mask for microfluidic chip fabrication

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Zhang, Min; Desta, Yohannes; Melzak, J.; Wu, C. H.; Peng, Zhengchun

    2006-02-01

    X-ray lithography is a very good option for the fabrication of micro-devices especially when high aspect ratio patterns are required. Membrane-based x-ray masks are commonly used for high-resolution x-ray lithography. A thin layer of silicon nitride (Si3N4) or silicon carbide (SiC) film (1-2 µm) is normally used as the membrane material for x-ray mask fabrication (Wells G M, Reilly M, Nachman R, Cerrina F, El-Khakani M A and Chaker M 1993 Mater. Res. Soc. Conf. Proc. 306 81-9 Shoki T, Nagasawa H, Kosuga H, Yamaguchi Y, Annaka N, Amemiya I and Nagarekawa O 1993 SPIE Proc. 1924 450-6). The freestanding membrane window of an x-ray mask, which defines the exposing area of the x-ray mask, can be obtained by etching a pre-defined area on a silicon wafer from the backside (Wang L, Desta Y, Fettig R K, Goettert J, Hein H, Jakobs P and Chulz J 2004 J. Micromech. Microeng. 14 722-6). Usually, the window size of an x-ray mask is around 20 × 20 mm because of the low tensile stress of the membrane (10-100 MPa), and the larger window dimension of an x-ray mask may cause the deformation of membranes and lower the mask quality. However, x-ray masks with larger windows are preferred for micro-device fabrication in order to increase the productivity. We analyzed the factors which influence the flatness of large format x-ray masks and fabricated x-ray masks with a window size of 55 × 55 mm and 46 × 65 mm on 1 µm thick membranes by increasing the tensile stress of the membranes (>300 MPa) and optimizing the stress of the absorber layer. The large format x-ray mask was successfully applied for the fabrication of microfluidic chips.

  13. X-ray lithography using holographic images

    DOEpatents

    Howells, Malcolm R.; Jacobsen, Chris

    1995-01-01

    A non-contact X-ray projection lithography method for producing a desired X-ray image on a selected surface of an X-ray-sensitive material, such as photoresist material on a wafer, the desired X-ray image having image minimum linewidths as small as 0.063 .mu.m, or even smaller. A hologram and its position are determined that will produce the desired image on the selected surface when the hologram is irradiated with X-rays from a suitably monochromatic X-ray source of a selected wavelength .lambda.. On-axis X-ray transmission through, or off-axis X-ray reflection from, a hologram may be used here, with very different requirements for monochromaticity, flux and brightness of the X-ray source. For reasonable penetration of photoresist materials by X-rays produced by the X-ray source, the wavelength X, is preferably chosen to be no more than 13.5 nm in one embodiment and more preferably is chosen in the range 1-5 nm in the other embodiment. A lower limit on linewidth is set by the linewidth of available microstructure writing devices, such as an electron beam.

  14. Bendable X-ray Optics for High Resolution Imaging

    NASA Technical Reports Server (NTRS)

    Gubarev, M.; Ramsey, B.; Kilaru, K.; Atkins, C.; Broadway, D.

    2014-01-01

    Current state-of the-art for x-ray optics fabrication calls for either the polishing of massive substrates into high-angular-resolution mirrors or the replication of thin, lower-resolution, mirrors from perfectly figured mandrels. Future X-ray Missions will require a change in this optics fabrication paradigm in order to achieve sub-arcsecond resolution in light-weight optics. One possible approach to this is to start with perfectly flat, light-weight surface, bend it into a perfect cone, form the desired mirror figure by material deposition, and insert the resulting mirror into a telescope structure. Such an approach is currently being investigated at MSFC, and a status report will be presented detailing the results of finite element analyses, bending tests and differential deposition experiments.

  15. Discovery of Spatial and Spectral Structure in the X-Ray Emission from the Crab Nebula

    NASA Technical Reports Server (NTRS)

    Weisskopf, Martin C.; Hester, J. Jeff; Tennant, Allyn F.; Elsner, Ronald F.; Schulz, Norbert S.; Marshall, Herman L.; Karovska, Margarita; Nichols, Joy S.; Swartz, Douglas A.; Kolodziejczak, Jeffery J.

    2000-01-01

    The Chandra X-Ray Observatory observed the Crab Nebula and pulsar during orbital calibration. Zeroth-order images with the High-Energy Transmission Grating (HETG) readout by the Advanced Charge Coupled Devices (CCD) Imaging Spectrometer spectroscopy array (ACIS-S) show a striking richness of X-ray structure at a resolution comparable to that of the best ground-based visible-light observations. The HETG-ACIS-S images reveal, for the first time, an X-ray inner ring within the X-ray torus, the suggestion of a hollow-tube structure for the torus, and X-ray knots along the inner ring and (perhaps) along the inward extension of the X-ray jet. Although complicated by instrumental effects and the brightness of the Crab Nebula, the spectrometric analysis shows systematic variations of the X-ray spectrum throughout the nebula.

  16. X-ray grid-detector apparatus

    DOEpatents

    Boone, John M.; Lane, Stephen M.

    1998-01-27

    A hybrid grid-detector apparatus for x-ray systems wherein a microchannel plate structure has an air-interspaced grid portion and a phosphor/optical fluid-filled grid portion. The grids are defined by multiple adjacent channels separated by lead-glass septa. X-rays entering the air-interspaced grid portion at an angle of impingement upon the septa are attenuated, while non-impinging x-rays pass through to the phosphor/fluid filled portion. X-ray energy is converted to luminescent energy in the phosphor/fluid filled portion and the resultant beams of light are directed out of the phosphor/optical fluid filled portion to an imaging device.

  17. Investigating the Mechanism of Reversible Lithium Insertion into Anti-NASICON Fe 2(WO 4) 3

    DOE PAGES

    Barim, Gozde; Cottingham, Patrick; Zhou, Shiliang; ...

    2017-03-07

    The gram-scale preparation of Fe 2(WO 4) 3 by a new solution-based route and detailed characterization of the material are presented. The resulting Fe 2(WO 4) 3 undergoes a reversible electrochemical reaction against lithium centered around 3.0 V with capacities near 93% of the theoretical maximum. Evolution of the Fe 2(WO 4) 3 structure upon lithium insertion and deinsertion is probed using a battery of characterization techniques, including in situ X-ray diffraction, neutron total scattering, and X-ray absorption spectroscopy (XAS). A structural transformation from monoclinic to orthorhombic phases is confirmed during lithium intercalation. XAS and neutron total scattering measurements verifymore » that Fe 2(WO 4) 3 consists of trivalent iron and hexavalent tungsten ions. As lithium ions are inserted into the framework, iron ions are reduced to the divalent state, while the tungsten ions are electrochemically inactive and remain in the hexavalent state. Lastly, lithium insertion occurs via a concerted rotation of the rigid polyhedra in the host lattice driven by electrostatic interactions with the Li + ions; the magnitude of these polyhedral rotations was found to be slightly larger for Fe 2(WO 4) 3 than for the Fe 2(MoO 4) 3 analog.« less

  18. Investigating the Mechanism of Reversible Lithium Insertion into Anti-NASICON Fe 2(WO 4) 3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barim, Gozde; Cottingham, Patrick; Zhou, Shiliang

    The gram-scale preparation of Fe 2(WO 4) 3 by a new solution-based route and detailed characterization of the material are presented. The resulting Fe 2(WO 4) 3 undergoes a reversible electrochemical reaction against lithium centered around 3.0 V with capacities near 93% of the theoretical maximum. Evolution of the Fe 2(WO 4) 3 structure upon lithium insertion and deinsertion is probed using a battery of characterization techniques, including in situ X-ray diffraction, neutron total scattering, and X-ray absorption spectroscopy (XAS). A structural transformation from monoclinic to orthorhombic phases is confirmed during lithium intercalation. XAS and neutron total scattering measurements verifymore » that Fe 2(WO 4) 3 consists of trivalent iron and hexavalent tungsten ions. As lithium ions are inserted into the framework, iron ions are reduced to the divalent state, while the tungsten ions are electrochemically inactive and remain in the hexavalent state. Lastly, lithium insertion occurs via a concerted rotation of the rigid polyhedra in the host lattice driven by electrostatic interactions with the Li + ions; the magnitude of these polyhedral rotations was found to be slightly larger for Fe 2(WO 4) 3 than for the Fe 2(MoO 4) 3 analog.« less

  19. Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shu, Deming, E-mail: shu@aps.anl.gov; Shvyd’ko, Yuri V.; Stoupin, Stanislav

    2016-07-27

    A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

  20. Status of PLS-II Upgrade Program

    NASA Astrophysics Data System (ADS)

    Kim, Kyung-Ryul; Wiedemann, Helmut; Park, Sung-Ju; Kim, Dong-Eon; Park, Chong-Do; Park, Sung-Soo; Kim, Seong-Hwan; Kim, Bongsoo; Namkung, Won; Nam, Sanghoon; Ree, Moonhor

    2010-06-01

    The Pohang Light Source (PLS) at the Pohang Accelerator Laboratory has been operated first at 2.0 GeV since 1995, and later was upgraded to 2.5 GeV. During this time, 6 insertion devices like undulators and multipole wigglers have been put into operation to produce special photon beams, with a total of 27 beamlines installed and 3 beamlines under construction. Recently, Korea synchrotron user's community is demanding high beam stability, higher photon energies as well as more straight sections for insertion devices in the PLS. To meet the user requirements, the PLS-II upgrade program has been launched in January, 2009, incorporating a modified chromatic version of Double Bend Achromat (DBA) to achieve almost twice as many straight sections as the current PLS with a design goal of the relatively low emittance, ɛ, of 5.9 nmṡrad. In the PLS-II, the top-up injection using full energy linac is planned for much higher stable beam as well and thus the production of hard x-ray undulator radiation of 8 to 13 keV is anticipated to allow for the successful research program namely Protein Crystallography. The PLS-II machine components of storage ring, linear accelerator and photon beamlines will be partly dismantled and reinstalled in a 6-months shutdown beginning January, 2011 and then the PLS-II upgrade be started the initial commissioning with a 100 mA beam current from July in 2011.

  1. Planetary Observations in the Soft X-ray band; Present status and Future CMOS based technology

    NASA Astrophysics Data System (ADS)

    Kenter, A.; Kraft, R.; Murray, S.; Smith, R.; George, F.; Branduardi-Raymont, G.; Roediger, E.; Forman, W.; Elvis, M.

    2013-12-01

    Virtually every object in the Solar system emits X-rays, and X-ray studies of these objects often provides information that cannot be obtained by observations in other bands. The Solar Wind Charge Exchange (SWX) has revealed the nature and constituents of everything from comets, to the magnetosphere of the Earth and the gas giants. X-ray fluorescence observations of atmosphere-less rocky bodies have revealed their surface composition and gross morphology. Existing data, however, have been limited by observations with state of the art Earth-orbiting telescopes (e.g. Chandra, XMM-Newton, and Suzaku) or in-situ instruments with limited capabilities. We are developing CMOS imaging detectors optimized for use as soft x-ray imaging spectrometers. These devices, when coupled to a light-weight focusing optic or mechanical collimator, would be ideal for examining X-ray emission within the Solar System with unprecedented spatial, spectral and temporal resolution. CMOS devices, apart from their observational capabilities, would be ideal for a planetary mission as they consume very little power (~mW) and require only modest cooling. Furthermore, CMOS devices, unlike conventional CCDs, are extremely radiation hard (>5MRad) and could withstand even the hostile radiation environment of a Jovian orbit with little or no performance degradation. The devices can also be read at high (hundreds to thousands of frames per second) frame rates at low noise, a critical requirement given the high count rates (thousands of cts per second). Our CMOS imaging detectors are back thinned and optimized to detect very soft X-ray emission from light elements such as C,N,O,P,S as well as emission from higher Z elements such as Fe and Ti. This sensor can also resolve the strong CX emission lines of O present is the magnetospheric X-ray emission of the gas giants, as well as thermal and non-thermal bremsstrahlung. We could also detect and study the temporal evolution X-ray synchrotron emission from ultra-relativistic electrons, indicative of strong magnetohydrodynamic shocks. In this poster we outline some of the planetary investigations that could be made with this technology, and present the current status of our instrumentation development. We also compare the capabilities of our X-ray imaging spectrometer on a dedicated mission to Jupiter with the results obtained with Chandra. Our instrument, on a dedicated mission to Jupiter, could obtain more data on the Jovian auroras and the Io plasma torus in five minutes than we could with weeks of continuous Chandra observation.

  2. Microchannel detector array for X-rays and UV

    NASA Technical Reports Server (NTRS)

    Timothy, J. G.; Bybee, R. L.

    1976-01-01

    Device employs sensitive photoelectric electrodes and solid-state memory, can be used at visible UV and X ray wavelengths, includes nonmagnetic proximity focusing, and is immune to high energy charged-particle background.

  3. High quantum efficiency megavoltage imaging with thick scintillator detectors for image guided radiation therapy

    NASA Astrophysics Data System (ADS)

    Gopal, Arun

    In image guided radiation therapy (IGRT), imaging devices serve as guidance systems to aid patient set-up and tumor volume localization. Traditionally, 2-D megavoltage x-ray imagers, referred to as electronic portal imaging devices (EPIDs), have been used for planar target localization, and have recently been extended to perform 3-D volumetric reconstruction via cone-beam computed tomography (CBCT). However, current EPIDs utilize thin and inefficient phosphor screen detectors and are subsequently limited by poor soft tissue visualization, which limits their use for CBCT. Therefore, the use of thick scintillation media as megavoltage x-ray detectors for greater x-ray sensitivity and enhanced image quality has recently been of significant interest. In this research, two candidates for thick scintillators: CsI(Tl) and terbium doped scintillation glass were investigated in separate imaging configurations. In the first configuration, a thick scintillation crystal (TSC) consisting of a thick, monolithic slab of CsI(Tl) was coupled to a mirror-lens-camera system. The second configuration is based on a fiber-optic scintillation glass array (FOSGA), wherein the scintillation glass is drawn into long fiber-optic conduits, inserted into a grid-type housing constructed out of polymer-tungsten alloy, and coupled to an array of photodiodes for digital read-out. The imaging prototypes were characterized using theoretical studies and imaging measurements to obtain fundamental metrics of imaging performance. Spatial resolution was measured based on a modulation transfer function (MTF), noise was evaluated in terms of a noise power spectrum (NPS), and overall contrast was characterized in the form of detective quantum efficiency (DQE). The imaging studies were used to optimize the TSC and FOSGA imagers and propose prototype configurations for order-of-magnitude improvements in overall image quality. In addition, a fast and simple technique was developed to measure the MTF, NPS, and DQE metrics for clinical EPID and CBCT systems based on a novel adaptation of a traditional line-pair resolution bar-pattern. This research provides two significant benefits to radiotherapy: the characterization of a new generation of thick scintillator based megavoltage x-ray imagers for CBCT based IGRT, and the novel adaptation of fundamental imaging metrics from imaging research to routine clinical performance monitoring.

  4. Temperature dependence of a superconducting tunnel junction x-ray detector

    NASA Astrophysics Data System (ADS)

    Hiller, Lawrence J.; Labov, Simon E.; Mears, Carl A.; Barfknecht, Andrew T.; Frank, Matthias A.; Netel, Harrie; Lindeman, Mark A.

    1995-09-01

    Superconducting tunnel junctions can be used as part of a high-resolution, energy-dispersive x- ray detector. The energy of the absorbed x ray is used to break superconducting electron pairs, producing on the order of 10(superscript 6) excitations, called quasiparticles. The number of quasiparticles produced is proportional to the energy of the absorbed x ray. When a bias voltage is maintained across the barrier, these quasiparticles produce a net tunneling current. Either the peak tunneling current or the total tunneled charge may be measured to determine the energy of the absorbed x ray. The tunneling rate, and therefore the signal, is enhanced by the use of a quasiparticle trap near the tunnel barrier. The trapping efficiency is improved by decreasing the energy gap, though this reduces the maximum temperature at which the device may operate. In our niobium/aluminum configuration, we can very the energy gap in the trapping layer by varying its thickness. This paper examines the performance of two devices with 50 nm aluminum traps at temperatures ranging from 100 mK to 700 mK. We found that this device has a very good energy resolution of about 12 eV FWHM at 1 keV. This energy resolution is independent of temperature for much of this temperature range.

  5. Digital imaging with solid state x-ray image intensifiers

    NASA Astrophysics Data System (ADS)

    Damento, Michael A.; Radspinner, Rachel; Roehrig, Hans

    1999-10-01

    X-ray cameras in which a CCD is lens coupled to a large phosphor screen are known to suffer from a loss of x-ray signal due to poor light collection from conventional phosphors, making them unsuitable for most medical imaging applications. By replacing the standard phosphor with a solid-state image intensifier, it may be possible to improve the signal-to-noise ratio of the images produced with these cameras. The solid-state x-ray image intensifier is a multi- layer device in which a photoconductor layer controls the light output from an electroluminescent phosphor layer. While prototype devices have been used for direct viewing and video imaging, they are only now being evaluated in a digital imaging system. In the present work, the preparation and evaluation of intensifiers with a 65 mm square format are described. The intensifiers are prepared by screen- printing or doctor blading the following layers onto an ITO coated glass substrate: ZnS phosphor, opaque layer, CdS photoconductor, and carbon conductor. The total thickness of the layers is approximately 350 micrometers , 350 VAC at 400 Hz is applied to the device for operation. For a given x-ray dose, the intensifiers produce up to three times the intensity (after background subtracting) of Lanex Fast Front screens. X-ray images produced with the present intensifiers are somewhat noisy and their resolution is about half that of Lanex screens. Modifications are suggested which could improve the resolution and noise of the intensifiers.

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

    NASA Astrophysics Data System (ADS)

    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.

  7. Digital X-ray camera for quality evaluation three-dimensional topographic reconstruction of single crystals of biological macromolecules

    NASA Technical Reports Server (NTRS)

    Borgstahl, Gloria (Inventor); Lovelace, Jeff (Inventor); Snell, Edward Holmes (Inventor); Bellamy, Henry (Inventor)

    2008-01-01

    The present invention provides a digital topography imaging system for determining the crystalline structure of a biological macromolecule, wherein the system employs a charge coupled device (CCD) camera with antiblooming circuitry to directly convert x-ray signals to electrical signals without the use of phosphor and measures reflection profiles from the x-ray emitting source after x-rays are passed through a sample. Methods for using said system are also provided.

  8. Protection of the electronic components of measuring equipment from the X-ray radiation

    NASA Astrophysics Data System (ADS)

    Perez Vasquez, N. O.; Kostrin, D. K.; Uhov, A. A.

    2018-02-01

    In this work the effect of X-ray radiation on the operation of integrated circuits of the measurement equipment is discussed. The results of the calculations of a shielding system, allowing using integrated circuits with a high degree of integration in the vicinity of the X-ray source, are shown. The results of the verification of two measurement devices that was used for more than five years in the facility for training and testing of X-ray tubes are presented.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Higashi, T.; Osada, T.; Aoyama, W.

    A new dental x-ray fluorographic unit has been developed. This unit is composed of small intraoral x-ray tube, a compact x-ray image intensifier, and a high-resolution TV system. The purposes for developing this equipment were to (1) directly observe the tooth during endodontic procedures and (2) reduce x-ray exposure to the patient and the dentist. The radiation exposure can be reduced to about 1/600 the exposure used with conventional dental film. In clinical trials, a satisfactory fluorographic dental image for endodontic treatment was obtained with this new device.

  10. X-ray versus gamma irradiation effects on polymers

    NASA Astrophysics Data System (ADS)

    Croonenborghs, B.; Smith, M. A.; Strain, P.

    2007-11-01

    Today, the most common methods used for medical device sterilisation are by gaseous ethylene oxide and by electron beam or gamma irradiation. With X-ray sterilisation about to enter the market, its material compatibility needs to be assessed at doses typically encountered during a sterilisation process. This paper reports on a study that compares the effects of exposing different types of plastics that are commonly used in medical devices to 60Co or to 5 MeV X-rays. The dose rate for both irradiation modalities was of the same order of magnitude. Under these conditions, both types of radiation are found to have similar effects on polymer properties.

  11. Small Pixel Hybrid CMOS X-ray Detectors

    NASA Astrophysics Data System (ADS)

    Hull, Samuel; Bray, Evan; Burrows, David N.; Chattopadhyay, Tanmoy; Falcone, Abraham; Kern, Matthew; McQuaide, Maria; Wages, Mitchell

    2018-01-01

    Concepts for future space-based X-ray observatories call for a large effective area and high angular resolution instrument to enable precision X-ray astronomy at high redshift and low luminosity. Hybrid CMOS detectors are well suited for such high throughput instruments, and the Penn State X-ray detector lab, in collaboration with Teledyne Imaging Sensors, has recently developed new small pixel hybrid CMOS X-ray detectors. These prototype 128x128 pixel devices have 12.5 micron pixel pitch, 200 micron fully depleted depth, and include crosstalk eliminating CTIA amplifiers and in-pixel correlated double sampling (CDS) capability. We report on characteristics of these new detectors, including the best read noise ever measured for an X-ray hybrid CMOS detector, 5.67 e- (RMS).

  12. Initial experimental demonstration of the principles of a xenon gas shield designed to protect optical components from soft x-ray induced opacity (blanking) in high energy density experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Swadling, G. F.; Ross, J. S.; Manha, D.

    The design principles of a xenon gas shield device that is intended to protect optical components from x-ray induced opacity (“x-ray blanking”) have been experimentally demonstrated at the OMEGA-60 Laser Facility at the Laboratory for Laser Energetics, University of Rochester. A volume of xenon gas placed in front of an optical component absorbs the incoming soft x-ray radiation but transmits optical and ultra-violet radiation. The time-resolved optical (532 nm) transmission of samples was recorded as they were exposed to soft x-rays produced by a gold sphere source (1.5 kJ sr $-$1, 250–300 eV). Blanking of fused silica (SiO 2) wasmore » measured to occur over a range of time-integrated soft x-ray (<3 keV) fluence from ~0.2–2.5 J cm $-$2. A shield test device consisting of a 30 nm silicon nitride (Si 3N 4) and a 10 cm long volume of 0.04 bar xenon gas succeeded in delaying loss of transmission through a magnesium fluoride sample; optical transmission was observed over a longer period than for the unprotected sample. It is hoped that the design of this x-ray shield can be scaled in order to produce a shield device for the National Ignition Facility optical Thomson scattering collection telescope, in order to allow measurements of hohlraum plasma conditions produced in inertial confinement fusion experiments. Finally, if successful, it will also have applications in many other high energy density experiments where optical and ultra-violet measurements are desirable.« less

  13. Solar XUV Imaging and Non-dispersive Spectroscopy for Solar-C Enabled by Scientific CMOS APS Arrays

    NASA Astrophysics Data System (ADS)

    Stern, Robert A.; Lemen, J. R.; Shing, L.; Janesick, J.; Tower, J.

    2009-05-01

    Monolithic CMOS Advanced Pixel Sensor (APS) arrays are showing great promise as eventual replacements for the current workhorse of solar physics focal planes, the scientific CCD. CMOS APS devices have individually addressable pixels, increased radiation tolerance compared to CCDs, and require lower clock voltages, and thus lower power. However, commercially available CMOS chips, while suitable for use with intensifiers or fluorescent coatings, are generally not optimized for direct detection of EUV and X-ray photons. A high performance scientific CMOS array designed for these wavelengths will have significant new capabilities compared to CCDs, including the ability to read out small regions of the solar disk at high (sub sec) cadence, count single X-ray photons with Fano-limited energy resolution, and even operate at room temperature with good noise performance. Such capabilities will be crucial for future solar X-ray and EUV missions such as Solar-C. Sarnoff Corporation has developed scientific grade, monolithic CMOS arrays for X-ray imaging and photon counting. One prototype device, the "minimal" array, has 8 um pixels, is 15 to 25 um thick, is fabricated on high-resistivity ( 10 to 20 kohm-cm) Si wafers, and can be back-illuminated. These characteristics yield high quantum efficiency and high spatial resolution with minimal charge sharing among pixels, making it ideal for the detection of keV X-rays. When used with digital correlated double sampling, the array has demonstrated noise performance as low as 2 e, allowing single photon counting of X-rays over a range of temperatures. We report test results for this device in X-rays, and discuss the implications for future solar space missions.

  14. Initial experimental demonstration of the principles of a xenon gas shield designed to protect optical components from soft x-ray induced opacity (blanking) in high energy density experiments

    DOE PAGES

    Swadling, G. F.; Ross, J. S.; Manha, D.; ...

    2017-03-16

    The design principles of a xenon gas shield device that is intended to protect optical components from x-ray induced opacity (“x-ray blanking”) have been experimentally demonstrated at the OMEGA-60 Laser Facility at the Laboratory for Laser Energetics, University of Rochester. A volume of xenon gas placed in front of an optical component absorbs the incoming soft x-ray radiation but transmits optical and ultra-violet radiation. The time-resolved optical (532 nm) transmission of samples was recorded as they were exposed to soft x-rays produced by a gold sphere source (1.5 kJ sr $-$1, 250–300 eV). Blanking of fused silica (SiO 2) wasmore » measured to occur over a range of time-integrated soft x-ray (<3 keV) fluence from ~0.2–2.5 J cm $-$2. A shield test device consisting of a 30 nm silicon nitride (Si 3N 4) and a 10 cm long volume of 0.04 bar xenon gas succeeded in delaying loss of transmission through a magnesium fluoride sample; optical transmission was observed over a longer period than for the unprotected sample. It is hoped that the design of this x-ray shield can be scaled in order to produce a shield device for the National Ignition Facility optical Thomson scattering collection telescope, in order to allow measurements of hohlraum plasma conditions produced in inertial confinement fusion experiments. Finally, if successful, it will also have applications in many other high energy density experiments where optical and ultra-violet measurements are desirable.« less

  15. Symposium N: Materials and Devices for Thermal-to-Electric Energy Conversion

    DTIC Science & Technology

    2010-08-24

    X - ray diffraction, transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. Thermal conductivity measurements...SEM), X - ray diffraction (XRD) measurements as well as Raman spectroscopy. The results from these techniques indicate a clear modification...was examined by using scanning electron microscope (SEM; HITACHI S-4500 model) attached with an energy dispersive x - ray spectroscopy. The electrical

  16. Conformational transition of membrane-associated terminally-acylated HIV-1 Nef

    PubMed Central

    Akgun, Bulent; Satija, Sushil; Nanda, Hirsh; Pirrone, Gregory F.; Shi, Xiaomeng; Engen, John R.; Kent, Michael S.

    2013-01-01

    Many proteins are post-translationally modified by acylation targetting them to lipid membranes. While methods such as X-ray crystallography and NMR are available to determine the structure of folded proteins in solution, the precise position of folded domains relative to a membrane remains largely unknown. We used neutron and X-ray reflection methods to measure the displacement of the core domain of HIV Nef from lipid membranes upon insertion of the N-terminal myristate group. Nef is one of several HIV-1 accessory proteins and an essential factor in AIDS progression. Upon insertion of the myristate and residues from the N-terminal arm, Nef transitions from a closed to open conformation that positions the core domain 70 Å from the lipid headgroups. This work rules out speculation that the Nef core remains closely associated with the membrane to optimize interactions with the cytoplasmic domain of MHC-1. PMID:24035710

  17. Sub-micrometer resolution proximity X-ray microscope with digital image registration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chkhalo, N. I.; Salashchenko, N. N.; Sherbakov, A. V., E-mail: SherbakovAV@ipm.sci-nnov.ru

    A compact laboratory proximity soft X-ray microscope providing submicrometer spatial resolution and digital image registration is described. The microscope consists of a laser-plasma soft X-ray radiation source, a Schwarzschild objective to illuminate the test sample, and a two-coordinate detector for image registration. Radiation, which passes through the sample under study, generates an absorption image on the front surface of the detector. Optical ceramic YAG:Ce was used to convert the X-rays into visible light. An image was transferred from the scintillator to a charge-coupled device camera with a Mitutoyo Plan Apo series lens. The detector’s design allows the use of lensesmore » with numerical apertures of NA = 0.14, 0.28, and 0.55 without changing the dimensions and arrangement of the elements of the device. This design allows one to change the magnification, spatial resolution, and field of view of the X-ray microscope. A spatial resolution better than 0.7 μm and an energy conversion efficiency of the X-ray radiation with a wavelength of 13.5 nm into visible light collected by the detector of 7.2% were achieved with the largest aperture lens.« less

  18. Effect of Cricoid Pressure on Laryngeal View During Macintosh, McGrath MAC X-Blade and GlideScope Video Laryngoscopies

    PubMed Central

    Arslan, Zehra İpek; Solak, Mine

    2017-01-01

    Objective Cricoid pressure is useful in fasted patients requiring emergency intubation. We compared the effect of cricoid pressure on laryngeal view during Macintosh, McGrath MAC X-Blade and GlideScope video laryngoscopy. Methods After obtaining approval from the Human Research Ethics Committee and written informed consent from patients, we enrolled 120 patients (American Society of Anesthesiologists I–II, age 18–65 years) undergoing elective surgery that required endotracheal intubation in this prospective randomised study. Patients were divided into three groups (Macintosh, McGrath MAC X-Blade and GlideScope). Results Demographic and airway variables were similar in the groups. Cormack-Lehane grades were improved or unchanged on using cricoid pressure in Macintosh and McGrath MAC X-Blade groups. However, laryngeal views worsened in 12 patients (30%), remained unchanged in 26 patients (65%) and improved in 2 patients (5%) in the GlideScope group (p<0.001). Insertion and intubation times for Macintosh and McGrath MAC X-Blade video laryngoscopes were similar. Insertion times for GlideScope and Macintosh video laryngoscopes were similar, but were longer than those for the McGrath MAC X-Blade video laryngoscope (p=0.02). Tracheal intubation took longer with the GlideScope video laryngoscope than with the other devices (p<0.001 and p=0.003). Mean arterial pressures after insertion increased significantly in Macintosh and GlideScope groups (p=0.004 and p=0.001, respectively) compared with post-induction values. Heart rates increased after insertion in all three groups compared with post-induction values (p<0.001). Need for optimisation manoeuvres and postoperative minor complications were comparable in all three groups. Conclusion Although all three devices are useful for normal or difficult intubation, cricoid pressure improved Cormack-Lehane grades of Macintosh and McGrath MAC X-Blade video laryngoscopes but statistically significantly worsened that of the GlideScope video laryngoscope. PMID:29359076

  19. 21 CFR 892.1850 - Radiographic film cassette.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identification. A radiographic film cassette is a device intended for use during diagnostic x-ray procedures to hold a radiographic film in close contact with an x-ray intensifying screen and to provide a light...

  20. 13.1 micrometers hard X-ray focusing by a new type monocapillary X-ray optic designed for common laboratory X-ray source

    NASA Astrophysics Data System (ADS)

    Sun, Xuepeng; zhang, Xiaoyun; Zhu, Yu; Wang, Yabing; Shang, Hongzhong; Zhang, Fengshou; Liu, Zhiguo; Sun, Tianxi

    2018-04-01

    A new type of monocapillary X-ray optic, called 'two bounces monocapillary X-ray optics' (TBMXO), is proposed for generating a small focal spot with high power-density gain for micro X-ray analysis, using a common laboratory X-ray source. TBMXO is consists of two parts: an ellipsoidal part and a tapered part. Before experimental testing, the TBMXO was simulated by the ray tracing method in MATLAB. The simulated results predicted that the proposed TBMXO would produce a smaller focal spot with higher power-density gain than the ellipsoidal monocapillary X-ray optic (EMXO). In the experiment, the TBMXO performance was tested by both an optical device and a Cu target X-ray tube with focal spot of 100 μm. The results indicated that the TBMXO had a slope error of 57.6 μrad and a 13.1 μm focal spot and a 1360 gain in power density were obtained.

  1. Fentanyl Iontophoretic Transdermal System (IONSYS(®)) can be Safely used in the Hospital Environment with X-Rays, Computerized Tomography and Radiofrequency Identification Devices.

    PubMed

    Lemke, John; Sardariani, Edmond; Phipps, Joseph Bradley; Patel, Niki; Itri, Loretta M; Caravelli, James; Viscusi, Eugene R

    2016-09-01

    Fentanyl iontophoretic transdermal system (fentanyl ITS, IONSYS(®)) is a patient-controlled analgesia system used for the management of acute postoperative pain, designed to be utilized in a hospital setting. The objective of the two studies was to determine if fentanyl ITS could be safely used with X-rays, computerized tomography (CT) scans and radiofrequency identification (RFID) devices. The ITS system has two components: controller and drug unit; the studies utilized ITS systems without fentanyl, referred to as the ITS Placebo system. The first study evaluated the effect of X-radiation on the operation of an ITS Placebo system. Five ITS Placebo systems were exposed to X-rays (20 and 200 mSv total radiation dose-the 200 mSv radiation dose represents a tenfold higher exposure than in clinical practice) while operating in the Ready Mode and five were exposed while operating in the Dose Mode. The second study evaluated the effect of RFID (worst-case scenario of direct contact with an RFID transmitter) on the operation of an ITS Placebo system. During these tests, observations of the user interface and measurements of output voltage confirmed proper function throughout all operational modes (Ready Mode, Dose Mode, End-of-Use Mode, and End-of-Life Mode). The ITS Placebo system met all specifications and no functional anomalies were observed during and following X-ray exposure at two radiation dose levels or exposure at six different combinations of RFID frequencies and field strengths. The performance of the ITS system was unaffected by X-ray exposure levels well beyond those associated with diagnostic X-rays and CT scans, and by exposure to radiofrequency field strengths typically generated by RFID devices. These results provide added confidence to clinicians that the fentanyl ITS system does not need to be removed during diagnostic X-rays and CT scans and can also be utilized in close proximity to RFID devices. The studies and writing of this manuscript were supported financially by The Medicines Company.

  2. Characterization of the NEXT Hollow Cathode Inserts After Long-Duration Testing

    NASA Technical Reports Server (NTRS)

    Mackey, J.; Shastry, R.; Soulas, G.

    2017-01-01

    Hollow dispenser cathode inserts are a critical element of electric propulsion systems, and should therefore be well understood during long term operation to ensure reliable system performance. This work destructively investigated cathode inserts from the NEXT long-duration test which demonstrated 51,184 hours of high-voltage operation, 918 kg of propellant throughput, and 35.5 MN-s of total impulse. The characterization methods used include scanning electron microscopy with energy dispersive spectroscopy and X-ray diffraction. Microscopy analysis has been performed on fractured surfaces, emission surfaces, and metallographically polished cross-sections of post-test inserts and unused inserts. Impregnate distribution, etch region thickness, impregnate chemical content, emission surface topography, and emission surface phase identification are the primary factors investigated.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Filhol, J. M.; Couprie, M. E.; Level, M. P.

    SOLEIL is a third generation Synchrotron radiation Source, under construction in France at St Aubin, near Paris. The Storage Ring consists in a 357 m circumference ring, with 16 cells and 24 straight sections (4x12m, 12x7m, 8x3.6m), out of which up to 21 will house insertion devices. The optics, with distributed dispersion, features a low 3.7 nm.rad emittance at the 2.75 GeV operating energy, so as to provide high brilliance, from the VUV up to the hard X ray domain. In order to provide a long lifetime, and beam position stabilities in the micron range, significant attention was paid atmore » each design stage (optics, magnets, beam position monitors, vacuum and RF systems,..), including the design of the building and infrastructure, the construction of which is now complete. This resulted in some unprecedented approaches such as the intensive use of NEG coating Aluminium vessels, or the development of a dedicated superconducting RF cavity and of 190 kW solid state RF amplifiers. The construction, started in 2002, is now completed. The injector system (100 MeV Linac) and the 3 Hz full energy Booster synchrotron have reached nominal operating conditions by fall 2005. The installation of the Storage Ring was just completed and its commissioning started in May 2006. First 9 turns in the ring were achieved on May the 14th, and visible synchrotron radiation was also observed on a CCD camera. Innovative insertion devices were designed and built so as to provide the best possible performances in an energy range as large as 5 eV to 20 keV. These are helical electromagnetic devices with 640 mm and 256 mm periods, APPLE II type undulators with 80 mm period, and in-vacuum hybrid undulators with 20 mm period. Two infra-red beamlines providing both edge and constant dipole field emission are also under construction and a superconducting wiggler is currently being designed in order to provide high flux in the 10 to 50 keV range. A first set of 10 beamlines (out of 24 included in the project) is being built and will be tested from summer 2006 onwards, with the aim of starting Users operation by the beginning of 2007.« less

  4. Nanostructuring and texturing of pulsed laser deposited hydroxyapatite thin films

    NASA Astrophysics Data System (ADS)

    Kim, Hyunbin; Catledge, Shane; Vohra, Yogesh; Camata, Renato; Lacefield, William

    2003-03-01

    Hydroxyapatite (HA) [Ca_10(PO_4)_6(OH)_2] is commonly deposited onto orthopedic and dental metallic implants to speed up bone formation around devices, allowing earlier stabilization in a patient. Pulsed laser deposition (PLD) is a suitable means of placing thin HA films on these implants because of its control over stoichiometry, crystallinity, and nanostructure. These characteristics determine the mechanical properties of the films that must be optimized to improve the performance of load-bearing implants and other devices that undergo bone insertion. We have used PLD to produce nanostructured and preferentially oriented HA films and evaluated their mechanical properties. Pure, highly crystalline HA films on Ti-6Al-4V substrates were obtained using a KrF excimer laser (248nm) with energy density of 4-8 J/cm^2 and deposition temperature of 500-700^rcC. Scanning electron and atomic force microscopies reveal that our careful manipulation of energy density and substrate temperature has led to films made up of HA grains in the nanometer scale. Broadening of x-ray diffraction peaks as a function of deposition temperature suggests it may be possible to control the film nanostructure to a great extent. X-ray diffraction also shows that as the laser energy density is increased in the 4-8 J/cm^2 range, the hexagonal HA films become preferentially oriented along the c-axis perpendicular to the substrate. Texture, nanostructure, and phase make-up all significantly influence the mechanical properties. We will discuss how each of these factors affects hardness and Young's modulus of the HA films as measured by nanoindentation.

  5. Fabrication of absorption gratings with X-ray lithography for X-ray phase contrast imaging

    NASA Astrophysics Data System (ADS)

    Wang, Bo; Wang, Yu-Ting; Yi, Fu-Ting; Zhang, Tian-Chong; Liu, Jing; Zhou, Yue

    2018-05-01

    Grating-based X-ray phase contrast imaging is promising especially in the medical area. Two or three gratings are involved in grating-based X-ray phase contrast imaging in which the absorption grating of high-aspect-ratio is the most important device and the fabrication process is a great challenge. The material with large atomic number Z is used to fabricate the absorption grating for excellent absorption of X-ray, and Au is usually used. The fabrication process, which involves X-ray lithography, development and gold electroplating, is described in this paper. The absorption gratings with 4 μm period and about 100 μm height are fabricated and the high-aspect-ratio is 50.

  6. X-Ray Diffraction Apparatus

    NASA Technical Reports Server (NTRS)

    Blake, David F. (Inventor); Bryson, Charles (Inventor); Freund, Friedmann (Inventor)

    1996-01-01

    An x-ray diffraction apparatus for use in analyzing the x-ray diffraction pattern of a sample is introduced. The apparatus includes a beam source for generating a collimated x-ray beam having one or more discrete x-ray energies, a holder for holding the sample to be analyzed in the path of the beam, and a charge-coupled device having an array of pixels for detecting, in one or more selected photon energy ranges, x-ray diffraction photons produced by irradiating such a sample with said beam. The CCD is coupled to an output unit which receives input information relating to the energies of photons striking each pixel in the CCD, and constructs the diffraction pattern of photons within a selected energy range striking the CCD.

  7. Toward Large-Area Sub-Arcsecond X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    O'Dell, Stephen L.; Aldcroft, Thomas L.; Allured, Ryan; Atkins, Carolyn; Burrows, David N.; Cao, Jian; Chalifoux, Brandon D.; Chan, Kai-Wing; Cotroneo, Vincenzo; Elsner, Ronald F.; hide

    2014-01-01

    The future of x-ray astronomy depends upon development of x-ray telescopes with larger aperture areas (>1 sq m) and finer angular resolution(<1).Combined with the special requirements of nested grazing incidence optics, the mass and envelope constraints of spaceborne telescopes render such advances technologically challenging. Achieving this goal will require precision fabrication, alignment, mounting, and assembly of large areas (>100 sq m) of lightweight (1 kg/sq m areal density) high quality mirrors-possibly entailing active (in-space adjustable) alignment and figure correction. This paper discusses relevant programmatic and technological issues and summarizes progress toward large area sub-arcsecond x-ray telescopes. Key words: X-ray telescopes, x-ray optics, active optics, electroactive devices, silicon mirrors, differential deposition, ion implantation.

  8. Feasibility of real-time magnetic resonance imaging-guided endomyocardial biopsies: An in-vitro study.

    PubMed

    Lossnitzer, Dirk; Seitz, Sebastian A; Krautz, Birgit; Schnackenburg, Bernhard; André, Florian; Korosoglou, Grigorios; Katus, Hugo A; Steen, Henning

    2015-07-26

    To investigate if magnetic resonance (MR)-guided biopsy can improve the performance and safety of such procedures. A novel MR-compatible bioptome was evaluated in a series of in-vitro experiments in a 1.5T magnetic resonance imaging (MRI) system. The bioptome was inserted into explanted porcine and bovine hearts under real-time MR-guidance employing a steady state free precession sequence. The artifact produced by the metal element at the tip and the signal voids caused by the bioptome were visually tracked for navigation and allowed its constant and precise localization. Cardiac structural elements and the target regions for the biopsy were clearly visible. Our method allowed a significantly better spatial visualization of the bioptoms tip compared to conventional X-ray guidance. The specific device design of the bioptome avoided inducible currents and therefore subsequent heating. The novel MR-compatible bioptome provided a superior cardiovascular magnetic resonance (imaging) soft-tissue visualization for MR-guided myocardial biopsies. Not at least the use of MRI guidance for endomyocardial biopsies completely avoided radiation exposure for both patients and interventionalists. MRI-guided endomyocardial biopsies provide a better than conventional X-ray guided navigation and could therefore improve the specificity and reproducibility of cardiac biopsies in future studies.

  9. Crohn's Disease

    MedlinePlus

    ... causes, such as infection. You may also undergo flexible sigmoidoscopy, colonoscopy, body CT, body MRI, MR enterography, upper GI, small ... Flexible sigmoidoscopy , performed by inserting a sigmoidoscope (a flexible tube ... can also sometimes be seen. Body CT scan , a special type of x-ray ...

  10. 4D nano-tomography of electrochemical energy devices using lab-based X-ray imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Heenan, T. M. M.; Finegan, D. P.; Tjaden, B.

    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 particularlymore » 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.« less

  11. Growth and Electronic Structure of Heusler Compounds for Use in Electron Spin Based Devices

    DTIC Science & Technology

    2015-06-01

    either Co– or MnSi– initiated films on c(4x4) GaAs. Studies using x - ray photoemission spectroscopy (XPS), STM/STS, and transmission electron microscopy...Co– or MnSi– initiated films on c(4x4) GaAs. Studies using x - ray photoemission spectroscopy (XPS), STM/STS, and transmission electron microscopy (TEM...diagram of the Palmstrøm lab in-situ growth and char- acterization setup, with 6 MBE growth chambers, 3 scanning probe microscopes, an x - ray

  12. Dose Matters: FDA's Guidance on Children's X-rays

    MedlinePlus

    ... Consumers Home For Consumers Consumer Updates Dose Matters: FDA's Guidance on Children's X-rays Share Tweet Linkedin ... extra care to “child size” the radiation dose. FDA’s Role The FDA's Center for Devices and Radiological ...

  13. An experimental evaluation of monochromatic x-ray beam position monitors at diamond light source

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bloomer, Chris, E-mail: chris.bloomer@diamond.ac.uk; Rehm, Guenther; Dolbnya, Igor P.

    Maintaining the stability of the X-ray beam relative to the sample point is of paramount importance for beamlines and users wanting to perform cutting-edge experiments. The ability to detect, and subsequently compensate for, variations in X-ray beam position with effective diagnostics has multiple benefits: a reduction in commissioning and start-up time, less ‘down-time’, and an improvement in the quality of acquired data. At Diamond Light Source a methodical evaluation of a selection of monochromatic X-ray Beam Position Monitors (XBPMs), using a range of position detection techniques, and from a range of suppliers, was carried out. The results of these experimentsmore » are presented, showing the measured RMS noise on the position measurement of each device for a given flux, energy, beam size, and bandwidth. A discussion of the benefits and drawbacks of each of the various devices and techniques is also included.« less

  14. The low intensity X-ray imaging scope /Lixiscope/

    NASA Technical Reports Server (NTRS)

    Yin, L. I.; Trombka, J. I.; Seltzer, S. M.; Webber, R. L.; Farr, M. R.; Rennie, J.

    1978-01-01

    A fully portable, small-format X-ray imaging system, Lixiscope (low intensity X-ray imaging scope) is described. In the prototype, which has been built to demonstrate the feasibility of the Lixiscope concept, only well-developed and available components have been used. Consideration is given to the principles of operation of the device, some of its performance characteristics as well as possible dental, medical and industrial applications.

  15. Design and fabrication of a CCD camera for use with relay optics in solar X-ray astronomy

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Configured as a subsystem of a sounding rocket experiment, a camera system was designed to record and transmit an X-ray image focused on a charge coupled device. The camera consists of a X-ray sensitive detector and the electronics for processing and transmitting image data. The design and operation of the camera are described. Schematics are included.

  16. Phantom evaluation of a cardiac SPECT/VCT system that uses a common set of solid-state detectors for both emission and transmission scans.

    PubMed

    Bai, Chuanyong; Conwell, Richard; Kindem, Joel; Babla, Hetal; Gurley, Mike; De Los Santos, Romer; Old, Rex; Weatherhead, Randy; Arram, Samia; Maddahi, Jamshid

    2010-06-01

    We developed a cardiac SPECT system (X-ACT) with low dose volume CT transmission-based attenuation correction (AC). Three solid-state detectors are configured to form a triple-head system for emission scans and reconfigured to form a 69-cm field-of-view detector arc for transmission scans. A near mono-energetic transmission line source is produced from the collimated fluorescence x-ray emitted from a lead target when the target is illuminated by a narrow polychromatic x-ray beam from an x-ray tube. Transmission scans can be completed in 1 min with insignificant patient dose (deep dose equivalent <5 muSv). We used phantom studies to evaluate (1) the accuracy of the reconstructed attenuation maps, (2) the effect of AC on image uniformity, and (3) the effect of AC on defect contrast (DC). The phantoms we used included an ACR phantom, an anthropomorphic phantom with a uniform cardiac insert, and an anthropomorphic phantom with two defects in the cardiac insert. The reconstructed attenuation coefficient of water at 140 keV was .150 +/- .003/cm in the uniform region of the ACR phantom, .151 +/- .003/cm and .151 +/- .002/cm in the liver and cardiac regions of the anthropomorphic phantom. The ACR phantom images with AC showed correction of the bowing effect due to attenuation in the images without AC (NC). The 17-segment scores of the images of the uniform cardiac insert were 78.3 +/- 6.5 before and 87.9 +/- 3.3 after AC (average +/- standard deviation). The inferior-to-anterior wall ratio and the septal-to-lateral wall ratio were .99 and 1.16 before and 1.02 and 1.00 after AC. The DC of the two defects was .528 and .156 before and .628 and .173 after AC. The X-ACT system generated accurate attenuation maps with 1-minute transmission scans. AC improved image quality and uniformity over NC.

  17. X-ray irradiation-induced structural changes on Single Wall Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Bardi, N.; Jurewicz, I.; King, A. K.; Alkhorayef, M. A.; Bradley, D.; Dalton, A. B.

    2017-11-01

    Dosimetry devices based on Carbon Nanotubes are a promising new technology. In particular using devices based on single wall Carbon Nanotubes may offer a tissue equivalent response with the possibility for device miniaturisation, high scale manufacturing and low cost. An important precursor to device fabrication requires a quantitative study of the effects of X-ray radiation on the physical and chemical properties of the individual nanotubes. In this study, we concentrate on the effects of relatively low doses, 20 cGy and 45 cGy , respectively. We use a range of characterization techniques including scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy to quantify the effects of the radiation dose on inherent properties of the nanotubes. Specifically we find that the radiation exposure results in a reduction in the sp2 nature of the nanotube bond structure. Moreover, our analysis indicates that the exposure results in nanotubes that have an increased defect density which ultimately effects the electrical properties of the nanotubes.

  18. Study of high resolution x-ray spectrometer concepts for NIF experiments

    NASA Astrophysics Data System (ADS)

    Hill, K. W.; Bitter, M.; Delgado-Aparicio, L.; Efthimion, P.; Gao, L.; Maddox, J.; Pablant, N. A.; Beiersdorfer, P.; Chen, H.; Coppari, F.; Ma, T.; Nora, R.; Scott, H.; Schneider, M.; Mancini, R.

    2015-11-01

    Options have been investigated for DIM-insertable (Diagnostic Instrument Manipulator) high resolution (E/ ΔE ~ 3000 - 5000) Bragg crystal x-ray spectrometers for experiments on the NIF. Of interest are time integrated Cu K- and Ta L-edge absorption spectra and time resolved Kr He- β emission from compressed symcaps for inference of electron temperature from dielectronic satellites and electron density from Stark broadening. Cylindrical and conical von Hamos, Johann, and advanced high throughput designs have been studied. Predicted x-ray intensities, spectrometer throughputs, spectral resolution, and spatial focusing properties, as well as lab evaluations of some spectrometer candidates will be presented. Performed under the auspices of the US DOE by PPPL under contract DE-AC02-09CH11466 and by LLNL under contract DE-AC52-07NA27344.

  19. An Underappreciated Radiation Hazard from High Voltage Electrodes in Vacuum.

    PubMed

    West, Adam D; Lasner, Zack; DeMille, David; West, Elizabeth P; Panda, Cristian D; Doyle, John M; Gabrielse, Gerald; Kryskow, Adam; Mitchell, Corinne

    2017-01-01

    The use of high voltage (HV) electrodes in vacuum is commonplace in physics laboratories. In such systems, it has long been known that electron emission from an HV cathode can lead to bremsstrahlung x rays; indeed, this is the basic principle behind the operation of standard x-ray sources. However, in laboratory setups where x-ray production is not the goal and no electron source is deliberately introduced, field-emitted electrons accelerated by HV can produce x rays as an unintended hazardous byproduct. Both the level of hazard and the safe operating regimes for HV vacuum electrode systems are not widely appreciated, at least in university laboratories. A reinforced awareness of the radiation hazards associated with vacuum HV setups would be beneficial. The authors present a case study of a HV vacuum electrode device operated in a university atomic physics laboratory. They describe the characterization of the observed x-ray radiation, its relation to the observed leakage current in the device, the steps taken to contain and mitigate the radiation hazard, and suggested safety guidelines.

  20. Imaging crystal spectrometer for high-resolution x-ray measurements on electron beam ion traps and tokamaks

    DOE PAGES

    Beiersdorfer, P.; Magee, E. W.; Hell, N.; ...

    2016-09-09

    Here, we describe a crystal spectrometer implemented on the Livermore electron beam ion traps that employ two spherically bent quartz crystals and a cryogenically cooled back-illuminated charge-coupled device detector to measure x rays with a nominal resolving power of λ/Δλ ≥ 10 000. Its focusing properties allow us to record x rays either with the plane of dispersion perpendicular or parallel to the electron beam and, thus, to preferentially select one of the two linear x-ray polarization components. Moreover, by choice of dispersion plane and focussing conditions, we use the instrument either to image the distribution of the ions withinmore » the 2 cm long trap region, or to concentrate x rays of a given energy to a point on the detector, which optimizes the signal-to-noise ratio. We demonstrate the operation and utility of the new instrument by presenting spectra of Mo 34+, which prepares the instrument for use as a core impurity diagnostic on the NSTX-U spherical torus and other magnetic fusion devices that employ molybdenum as plasma facing components.« less

  1. High Count-Rate Study of Two TES X-Ray Microcalorimeters With Different Transition Temperatures

    NASA Technical Reports Server (NTRS)

    Lee, Sang-Jun; Adams, Joseph S.; Bandler, Simon R.; Betancourt-Martinez, Gabriele L.; Chervenak, James A.; Eckart, Megan E.; Finkbeiner, Fred M.; Kelley, Richard L.; Kilbourne, Caroline A.; Porter, Frederick S.; hide

    2017-01-01

    We have developed transition-edge sensor (TES) microcalorimeter arrays with high count-rate capability and high energy resolution to carry out x-ray imaging spectroscopy observations of various astronomical sources and the Sun. We have studied the dependence of the energy resolution and throughput (fraction of processed pulses) on the count rate for such microcalorimeters with two different transition temperatures T(sub c). Devices with both transition temperatures were fabricated within a single microcalorimeter array directly on top of a solid substrate where the thermal conductance of the microcalorimeter is dependent upon the thermal boundary resistance between the TES sensor and the dielectric substrate beneath. Because the thermal boundary resistance is highly temperature dependent, the two types of device with different T(sub c)(sup s) had very different thermal decay times, approximately one order of magnitude different. In our earlier report, we achieved energy resolutions of 1.6 and 2.eV at 6 keV from lower and higher T(sub c) devices, respectively, using a standard analysis method based on optimal filtering in the low flux limit. We have now measured the same devices at elevated x-ray fluxes ranging from 50 Hz to 1000 Hz per pixel. In the high flux limit, however, the standard optimal filtering scheme nearly breaks down because of x-ray pile-up. To achieve the highest possible energy resolution for a fixed throughput, we have developed an analysis scheme based on the socalled event grade method. Using the new analysis scheme, we achieved 5.0 eV FWHM with 96 Percent throughput for 6 keV x-rays of 1025 Hz per pixel with the higher T(sub c) (faster) device, and 5.8 eV FWHM with 97 Percent throughput with the lower T(sub c) (slower) device at 722 Hz.

  2. X-Ray Imaging System

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The FluoroScan Imaging System is a high resolution, low radiation device for viewing stationary or moving objects. It resulted from NASA technology developed for x-ray astronomy and Goddard application to a low intensity x-ray imaging scope. FlouroScan Imaging Systems, Inc, (formerly HealthMate, Inc.), a NASA licensee, further refined the FluoroScan System. It is used for examining fractures, placement of catheters, and in veterinary medicine. Its major components include an x-ray generator, scintillator, visible light image intensifier and video display. It is small, light and maneuverable.

  3. Sub-Optical Lithography With Nanometer Definition Masks

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T.; Malek, Chantal Khan; Neogi, Jayant

    2000-01-01

    Nanometer feature size lithography represents a major paradigm shift for the electronics and micro-electro-mechanical industries. In this paper, we discuss the capacity of dynamic focused reactive ion beam (FIB) etching systems to undertake direct and highly anisotropic erosion of thick evaporated gold coatings on boron-doped silicon X-ray mask membranes. FIB offers a new level of flexibility in micro fabrication, allowing for fast fabrication of X-ray masks, where pattern definition and surface alteration are combined in the same step which eliminates the whole lithographic process, in particular resist, resist development, electro-deposition and resist removal. Focused ion beam diameters as small as 7 nm can be obtained enabling fabrication well into the sub-20 nm regime. In preliminary demonstrations of this X-ray mask fabrication technique 22 nm width lines were milled directly through 0.9 microns of gold and a miniature mass spectrometer pattern was milled through over 0.5 microns of gold. Also presented are the results of the shadow printing, using the large depth of field of synchrotron high energy parallel X-ray beam, of these and other sub-optical defined patterns in photoresist conformally coated over surfaces of extreme topographical variation. Assuming that electronic circuits and/or micro devices scale proportionally, the surface area of devices processed with X-ray lithography and 20 nm critical dimension X-ray masks would be 0.5% that of contemporary devices (350 nm CD). The 20 CD mask fabrication represents an initial effort - a further factor of three reduction is anticipated which represents a further order-of-magnitude reduction in die area.

  4. Design on the x-ray oral digital image display card

    NASA Astrophysics Data System (ADS)

    Wang, Liping; Gu, Guohua; Chen, Qian

    2009-10-01

    According to the main characteristics of X-ray imaging, the X-ray display card is successfully designed and debugged using the basic principle of correlated double sampling (CDS) and combined with embedded computer technology. CCD sensor drive circuit and the corresponding procedures have been designed. Filtering and sampling hold circuit have been designed. The data exchange with PC104 bus has been implemented. Using complex programmable logic device as a device to provide gating and timing logic, the functions which counting, reading CPU control instructions, corresponding exposure and controlling sample-and-hold have been completed. According to the image effect and noise analysis, the circuit components have been adjusted. And high-quality images have been obtained.

  5. Thin-Film Ferro Electric-Coupled Microstripline Phase Shifters With Reduced Device Hysteresis

    NASA Technical Reports Server (NTRS)

    Miranda, Felix A.; Romanofsky, Robert; Mueller, Carl H.; VanKeuls, Frederick

    2010-01-01

    This work deals with the performance of coupled microstripline phase shifters (CMPS) fabricated using BaxSr 1 -xTiO 3 (BST) ferroelectric thin films. The CMPS were fabricated using commercially available pulsed laser deposition BST films with Ba:Sr ratios of 30:70 and 20:80. Microwave characterization of these CMPS was performed at upper Kuband frequencies, particularly at frequencies near 16 and 18 GHz. X-ray diffraction studies indicate that the 30:70 films exhibit almost a 1:1 ratio between the in-plane and out-of-plane lattice parameters, suggesting that their cubics create strain -free films suitable for producing CMPS devices with reduced hysteresis in the paraelectric state. The quality of performance of the CMPS was studied based on their relative phase shift and insertion loss within the DC bias range of 0 to 400 V (i.e., E-field ranges within 0 to 53 V/micron). The performance of the CMPS was tested as a function of temperature to investigate their operation in the paraelectric, as well as in the ferroelectric, state (i.e., above and below the Curie temperature, respectively). The novel behavior discussed here is based on the experimental observation of the CMPS. This behavior, observed for the aforementioned cation ratio, highlights the relevance of good crystalline structure for high-quality CMPS.

  6. Influence of the insertion of a nano-oxide layer on the interfacial magnetism of FeMn /NiFe/Cu/NiFe spin valves

    NASA Astrophysics Data System (ADS)

    Tafur, Miguel; Alayo, W.; Munayco, P.; Baggio-Saitovitch, E.; Nascimento, V. P.; Alvarenga, A. D.; Brewer, W. D.

    2007-05-01

    We have studied the influence of an inserted nano-oxide layer (NOL) on the interfacial magnetism in spin-valve systems showing the giant magnetoresistance effect. Specifically, we performed a magnetic depth profile of these structures with and without a NOL, using the x-ray magnetic circular dichroism technique. We found that insertion of a NOL into the spin-valve structure is correlated with a stronger reduction of the magnetic moments at the ferromagnetic (FM)/NOL/FM interface in comparison with a spin valve without NOL.

  7. Co-complexes derived from alkene insertion to alkyne-dicobaltpentacarbonyl complexes: insight into the regioselectivity of pauson-khand reactions of cyclopropenes.

    PubMed

    Pallerla, Mahesh K; Yap, Glenn P A; Fox, Joseph M

    2008-08-15

    Described are the X-ray crystallographic and spectral properties of Co-complexes that were isolated from two Pauson-Khand reactions of chiral cyclopropenes. These are the first examples of isolated Co-complexes derived from the putative alkene-insertion intermediates of Pauson-Khand reactions. The binuclear Co-complexes are coordinated to mu-bonded, five-carbon "flyover" carbene ligands. It is proposed that the complexes result from cyclopropane fragmentation subsequent to alkene insertion. The observation of these metal complexes provides a rationale for the origin of regioselectivity in Pauson-Khand reactions of cyclopropenes.

  8. Design and performance of coded aperture optical elements for the CESR-TA x-ray beam size monitor

    NASA Astrophysics Data System (ADS)

    Alexander, J. P.; Chatterjee, A.; Conolly, C.; Edwards, E.; Ehrlichman, M. P.; Flanagan, J. W.; Fontes, E.; Heltsley, B. K.; Lyndaker, A.; Peterson, D. P.; Rider, N. T.; Rubin, D. L.; Seeley, R.; Shanks, J.

    2014-12-01

    We describe the design and performance of optical elements for an x-ray beam size monitor (xBSM), a device measuring e+ and e- beam sizes in the CESR-TA storage ring. The device can measure vertical beam sizes of 10 - 100 μm on a turn-by-turn, bunch-by-bunch basis at e± beam energies of 2 - 5 GeV. x-rays produced by a hard-bend magnet pass through a single- or multiple-slit (coded aperture) optical element onto a detector. The coded aperture slit pattern and thickness of masking material forming that pattern can both be tuned for optimal resolving power. We describe several such optical elements and show how well predictions of simple models track measured performances.

  9. The effects of the cathode array on emitted hard x-ray from a small plasma focus device

    NASA Astrophysics Data System (ADS)

    Piriaei, D.; Mahabadi, T. D.; Javadi, S.; Ghoranneviss, M.

    2017-08-01

    In this study, the effects of the cathode array variations on emitted hard x-rays from a small Mather type plasma focus device (450 J) were investigated. The gradual elimination of the cathode rods inside the cathode array of the device lowered the quality and quantity of the emitted hard x-rays at different pressure values of argon gas. We theorized that the variations of the cathode array were able to change some discharge parameters that could vary the number of the energetic runaway electrons generated during the pinch phase which were responsible for the created features of the emitted hard x-rays. On the other hand, we hypothesized that the removal of the cathode rods could influence the current sheath dynamics during all the phases of a shot including its average axial velocity which was demonstrated by using two axial magnetic probes. We also theorized that cathode rod omission from the cathode array could also increase the initial inductance and the impedance of the system, and the impurities inside the plasma during the pinch phase which could lead to the growth of the instabilities. Moreover, by using the wavelet technique and studying the Mirnov signals, it was shown that the decrease of the cathode rod number increased the plasma magnetic field fluctuations or instabilities (MHD activities) that adversely affected the pinch quality, and reduced the emitted hard x-rays.

  10. 21 CFR 892.5900 - X-ray radiation therapy system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

  11. 21 CFR 892.5900 - X-ray radiation therapy system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

  12. 21 CFR 892.5900 - X-ray radiation therapy system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

  13. 21 CFR 892.5900 - X-ray radiation therapy system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

  14. 21 CFR 892.5900 - X-ray radiation therapy system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false X-ray radiation therapy system. 892.5900 Section 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-rays used for radiation therapy. This generic type of device may include signal analysis and display...

  15. Soft x-ray pinhole imaging diagnostics for compact toroid plasmas

    NASA Astrophysics Data System (ADS)

    Crawford, E. A.; Taggart, D. P.; Bailey, A. D., III

    1990-10-01

    Soft x-ray pinhole imaging has recently become established as a valuable diagnostic for visualization of field reversed configuration (FRC) plasmas in the TRX-2, FRX-C/LSM devices. Gated MCP image converter devices with CsI cathodes and Be filters with a peak response around 11 nm wavelength are used for exposure durations ranging from a few tenths up to several microseconds. Results of experiments with single and Chevron channel plates are discussed along with estimates of linear exposure limitations with both film and CCD cameras as recording media. Plans for multiframe devices on the FRX-C/LSM and the LSX devices are also discussed.

  16. Edge enhancement algorithm for low-dose X-ray fluoroscopic imaging.

    PubMed

    Lee, Min Seok; Park, Chul Hee; Kang, Moon Gi

    2017-12-01

    Low-dose X-ray fluoroscopy has continually evolved to reduce radiation risk to patients during clinical diagnosis and surgery. However, the reduction in dose exposure causes quality degradation of the acquired images. In general, an X-ray device has a time-average pre-processor to remove the generated quantum noise. However, this pre-processor causes blurring and artifacts within the moving edge regions, and noise remains in the image. During high-pass filtering (HPF) to enhance edge detail, this noise in the image is amplified. In this study, a 2D edge enhancement algorithm comprising region adaptive HPF with the transient improvement (TI) method, as well as artifacts and noise reduction (ANR), was developed for degraded X-ray fluoroscopic images. The proposed method was applied in a static scene pre-processed by a low-dose X-ray fluoroscopy device. First, the sharpness of the X-ray image was improved using region adaptive HPF with the TI method, which facilitates sharpening of edge details without overshoot problems. Then, an ANR filter that uses an edge directional kernel was developed to remove the artifacts and noise that can occur during sharpening, while preserving edge details. The quantitative and qualitative results obtained by applying the developed method to low-dose X-ray fluoroscopic images and visually and numerically comparing the final images with images improved using conventional edge enhancement techniques indicate that the proposed method outperforms existing edge enhancement methods in terms of objective criteria and subjective visual perception of the actual X-ray fluoroscopic image. The developed edge enhancement algorithm performed well when applied to actual low-dose X-ray fluoroscopic images, not only by improving the sharpness, but also by removing artifacts and noise, including overshoot. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. 21 CFR 872.1830 - Cephalometer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... DENTAL DEVICES Diagnostic Devices § 872.1830 Cephalometer. (a) Identification. A cephalometer is a device used in dentistry during x-ray procedures. The device is intended to place and to hold a patient's head...

  18. New device for accurate measurement of the x-ray intensity distribution of x-ray tube focal spots.

    PubMed

    Doi, K; Fromes, B; Rossmann, K

    1975-01-01

    A new device has been developed with which the focal spot distribution can be measured accurately. The alignment and localization of the focal spot relative to the device are accomplished by adjustment of three micrometer screws in three orthogonal directions and by comparison of red reference light spots with green fluorescent pinhole images at five locations. The standard deviations for evaluating the reproducibility of the adjustments in the horizontal and vertical directions were 0.2 and 0.5 mm, respectively. Measurements were made of the pinhole images as well as of the line-spread functions (LSFs) and modulation transfer functions (MTFs) for an x-ray tube with focal spots of 1-mm and 50-mum nominal size. The standard deviations for the LSF and MTF of the 1-mm focal spot were 0.017 and 0.010, respectively.

  19. Comparative study of radiation emission without and with target in a 2.2 kJ plasma focus device

    NASA Astrophysics Data System (ADS)

    Khan, Muhammad Zubair; Ling, Yap Seong; San, Wong Chiow

    2014-03-01

    The radiation emission in a 2.2 kJ Mather-type dense plasma focus device is investigated using a five channel BPX65 PIN diode spectrometer. Estimated X-ray associated with the hollow anode without and with target in Argon gas medium is compared. At optimum conditions, the radiation emission from the system is found to be strongly influenced with target in hollow anode and the filling gas pressure. The maximum X-ray yield in 4π sr was obtained in case of hollow anode in argon gas medium with target "Lead" due to interaction of electron beam. Results indicated that an appropriate design of hollow anode with target could enhance the radiation emission by more intense interaction of expected electron beam with target. The outcomes are helpful in designing a plasma focus with enhanced X-ray radiation with improved shot to shot reproducibility in plasma focus device.

  20. Pneumocranium secondary to halo vest pin penetration through an enlarged frontal sinus.

    PubMed

    Cheong, Min Lee; Chan, Chris Yin Wei; Saw, Lim Beng; Kwan, Mun Keong

    2009-07-01

    We present a case report of a patient with pneumocranium secondary to halo vest pin penetration and a review of literature. The objectives of this study are to report a rare complication of halo vest pin insertion and to discuss methods of prevention of this complication. Halo vest orthosis is a commonly used and well-tolerated upper cervical spinal stabilizing device. Reports of complications related to pin penetration is rare and from our review, there has been no reports of pneumocranium occurring from insertion of pins following standard anatomical landmarks. A 57-year-old male sustained a type 1 traumatic spondylolisthesis of C2/C3 following a motor vehicle accident. During application of the halo vest, penetration of the left anterior pin through the abnormally enlarged frontal sinus occurred. The patient developed headache, vomiting and CSF rhinorrhoea over his left nostril. He was treated with intravenous Ceftriaxone for 1 week. This resulted in resolution of his symptoms as well as the pneumocranium. In conclusion, complications of halo vest pin penetration are rare and need immediate recognition. Despite the use of anatomical landmarks, pin penetration is still possible due to aberrant anatomy. All patients should have a skull X-ray with a radio-opaque marker done prior to placement of the halo vest pins and halo vest pins have to be inserted by experienced personnel to enable early detection of pin penetration.

  1. Valence change detection in memristive oxide based heterostructure cells by hard X-ray photoelectron emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Kindsmüller, A.; Schmitz, C.; Wiemann, C.; Skaja, K.; Wouters, D. J.; Waser, R.; Schneider, C. M.; Dittmann, R.

    2018-04-01

    The switching mechanism of valence change resistive memory devices is widely accepted to be an ionic movement of oxygen vacancies resulting in a valence change of the metal cations. However, direct experimental proofs of valence changes in memristive devices are scarce. In this work, we have employed hard X-ray photoelectron emission microscopy (PEEM) to probe local valence changes in Pt/ZrOx/Ta memristive devices. The use of hard X-ray radiation increases the information depth, thus providing chemical information from buried layers. By extracting X-ray photoelectron spectra from different locations in the PEEM images, we show that zirconia in the active device area is reduced compared to a neighbouring region, confirming the valence change in the ZrOx film during electroforming. Furthermore, we succeeded in measuring the Ta 4f spectrum for two different resistance states on the same device. In both states, as well as outside the device region, the Ta electrode is composed of different suboxides without any metallic contribution, hinting to the formation of TaOx during the deposition of the Ta thin film. We observed a reduction of the Ta oxidation state in the low resistance state with respect to the high resistive state. This observation is contradictory to the established model, as the internal redistribution of oxygen between ZrOx and the Ta electrode during switching would lead to an oxidation of the Ta layer in the low resistance state. Instead, we have to conclude that the Ta electrode takes an active part in the switching process in our devices and that oxygen is released and reincorporated in the ZrOx/TaOx bilayer during switching. This is confirmed by the degradation of the high resistance state during endurance measurements under vacuum.

  2. SU-E-I-91: Development of a Compact Radiographic Simulator Using Microsoft Kinect.

    PubMed

    Ono, M; Kozono, K; Aoki, M; Mizoguchi, A; Kamikawa, Y; Umezu, Y; Arimura, H; Toyofuku, F

    2012-06-01

    Radiographic simulator system is useful for learning radiographic techniques and confirmation of positioning before x-ray irradiation. Conventional x-ray simulators have drawbacks in cost and size, and are only applicable to situations in which position of the object does not change. Therefore, we have developed a new radiographic simulator system using an infrared-ray based three-dimensional shape measurement device (Microsoft Kinect). We made a computer program using OpenCV and OpenNI for processing of depth image data obtained from Kinect, and calculated the exact distance from Kinect to the object by calibration. Theobject was measured from various directions, and positional relationship between the x-ray tube and the object was obtained. X-ray projection images were calculated by projecting x-rays onto the mathematical three-dimensional CT data of a head phantom with almost the same size. The object was rotated from 0 degree (standard position) through 90 degrees in increments of 10 degrees, and the accuracy of the measured rotation angle values was evaluated. In order to improve the computational time, the projection image size was changed (512*512, 256*256, and 128*128). The x-ray simulation images corresponding to the radiographic images produced by using the x-ray tube were obtained. The three-dimensional position of the object was measured with good precision from 0 to 50 degrees, but above 50 degrees, measured position error increased with the increase of the rotation angle. The computational time and image size were 30, 12, and 7 seconds for 512*512, 256*256, and 128*128, respectively. We could measure the three-dimensional position of the object using properly calibrated Kinect sensor, and obtained projection images at relatively high-speed using the three-dimensional CTdata. It was suggested that this system can be used for obtaining simulated projection x-ray images before x-ray exposure by attaching this device onto an x-ray tube. © 2012 American Association of Physicists in Medicine.

  3. Synchrotron-based soft X-ray spectroscopic studies of the electronic structure of organic semiconducting molecules

    NASA Astrophysics Data System (ADS)

    Demasi, Alexander

    Organic molecules have been the subject of many scientific studies due to their potential for use in a new generation of optoelectronic and semiconducting devices, such as organic photovoltaics and organic light emitting diodes. These studies are motivated by the fact that organic semiconductor devices have several advantages over traditional inorganic semiconductor devices. Unlike inorganic semiconductors, where the electronic properties are a result of the deliberate introduction of dopants to the material, the properties of organic semiconductors are often intrinsic to the molecules themselves. As a result, organic semiconductor devices are frequently less susceptible to contamination by impurities than their inorganic counterparts, which results in the relatively lower cost of producing such devices. Accurate experimental determination of the bulk and surface electronic structure of organic semiconductors is a prerequisite in developing a comprehensive understanding of such materials. The organic materials studied in this thesis were N,N-Ethylene-bis(1,1,1trifluoropentane-2,4-dioneiminato)-copper(ii) (abbreviated Cu-TFAC), aluminum tris-8hydroxyquinoline (A1g3), lithium quinolate (Liq), tetracyanoquinodimethane (TCNQ), and tetrafluorotetracyanoquinodimethane (F4TCNQ). The electronic structures of these materials were measured with several synchrotron-based x-ray spectroscopies. X-ray photoemission spectroscopy was used to measure the occupied total density of states and the core-level states of the aforementioned materials. X-ray absorption spectroscopy (XAS) was used to probe the element-specific unoccupied partial density of states (PDOS); its angle-resolved variant was used to measure the orientation of the molecules in a film and, in some circumstances, to gauge the extent of an organic film's crystallinity. Most notably, x-ray emission spectroscopy (XES) measures the element- specific occupied PDOS and, when aided by XAS, resonant XES can additionally be used to probe the electronic structure of individual atomic sites within a molecule. Most of the results in this thesis are accompanied by the results of electronic structure calculations determined with density functional theory (DFT). DFT is a useful aid in interpreting the results of the x-ray spectroscopies employed. The experimental results, combined with DFT calculations, provide a wealth of information regarding the electronic structures of these organic materials. v

  4. X-rays only when you want them: optimized pump–probe experiments using pseudo-single-bunch operation

    PubMed Central

    Hertlein, M. P.; Scholl, A.; Cordones, A. A.; Lee, J. H.; Engelhorn, K.; Glover, T. E.; Barbrel, B.; Sun, C.; Steier, C.; Portmann, G.; Robin, D. S.

    2015-01-01

    Laser pump–X-ray probe experiments require control over the X-ray pulse pattern and timing. Here, the first use of pseudo-single-bunch mode at the Advanced Light Source in picosecond time-resolved X-ray absorption experiments on solutions and solids is reported. In this mode the X-ray repetition rate is fully adjustable from single shot to 500 kHz, allowing it to be matched to typical laser excitation pulse rates. Suppressing undesired X-ray pulses considerably reduces detector noise and improves signal to noise in time-resolved experiments. In addition, dose-induced sample damage is considerably reduced, easing experimental setup and allowing the investigation of less robust samples. Single-shot X-ray exposures of a streak camera detector using a conventional non-gated charge-coupled device (CCD) camera are also demonstrated. PMID:25931090

  5. Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance

    NASA Astrophysics Data System (ADS)

    Singh, K. P.; Stewart, G. C.; Westergaard, N. J.; Bhattacharayya, S.; Chandra, S.; Chitnis, V. R.; Dewangan, G. C.; Kothare, A. T.; Mirza, I. M.; Mukerjee, K.; Navalkar, V.; Shah, H.; Abbey, A. F.; Beardmore, A. P.; Kotak, S.; Kamble, N.; Vishwakarama, S.; Pathare, D. P.; Risbud, V. M.; Koyande, J. P.; Stevenson, T.; Bicknell, C.; Crawford, T.; Hansford, G.; Peters, G.; Sykes, J.; Agarwal, P.; Sebastian, M.; Rajarajan, A.; Nagesh, G.; Narendra, S.; Ramesh, M.; Rai, R.; Navalgund, K. H.; Sarma, K. S.; Pandiyan, R.; Subbarao, K.; Gupta, T.; Thakkar, N.; Singh, A. K.; Bajpai, A.

    2017-06-01

    The Soft X-ray focusing Telescope (SXT), India's first X-ray telescope based on the principle of grazing incidence, was launched aboard the AstroSat and made operational on October 26, 2015. X-rays in the energy band of 0.3-8.0 keV are focussed on to a cooled charge coupled device thus providing medium resolution X-ray spectroscopy of cosmic X-ray sources of various types. It is the most sensitive X-ray instrument aboard the AstroSat. In its first year of operation, SXT has been used to observe objects ranging from active stars, compact binaries, supernova remnants, active galactic nuclei and clusters of galaxies in order to study its performance and quantify its characteriztics. Here, we present an overview of its design, mechanical hardware, electronics, data modes, observational constraints, pipeline processing and its in-orbit performance based on preliminary results from its characterization during the performance verification phase.

  6. Generation of first hard X-ray pulse at Tsinghua Thomson Scattering X-ray Source.

    PubMed

    Du, Yingchao; Yan, Lixin; Hua, Jianfei; Du, Qiang; Zhang, Zhen; Li, Renkai; Qian, Houjun; Huang, Wenhui; Chen, Huaibi; Tang, Chuanxiang

    2013-05-01

    Tsinghua Thomson Scattering X-ray Source (TTX) is the first-of-its-kind dedicated hard X-ray source in China based on the Thomson scattering between a terawatt ultrashort laser and relativistic electron beams. In this paper, we report the experimental generation and characterization of the first hard X-ray pulses (51.7 keV) via head-on collision of an 800 nm laser and 46.7 MeV electron beams. The measured yield is 1.0 × 10(6) per pulse with an electron bunch charge of 200 pC and laser pulse energy of 300 mJ. The angular intensity distribution and energy spectra of the X-ray pulse are measured with an electron-multiplying charge-coupled device using a CsI scintillator and silicon attenuators. These measurements agree well with theoretical and simulation predictions. An imaging test using the X-ray pulse at the TTX is also presented.

  7. X-rays only when you want them: Optimized pump–probe experiments using pseudo-single-bunch operation

    DOE PAGES

    Hertlein, M. P.; Scholl, A.; Cordones, A. A.; ...

    2015-04-02

    Laser pump–X-ray probe experiments require control over the X-ray pulse pattern and timing. Here, the first use of pseudo-single-bunch mode at the Advanced Light Source in picosecond time-resolved X-ray absorption experiments on solutions and solids is reported. In this mode the X-ray repetition rate is fully adjustable from single shot to 500 kHz, allowing it to be matched to typical laser excitation pulse rates. Suppressing undesired X-ray pulses considerably reduces detector noise and improves signal to noise in time-resolved experiments. In addition, dose-induced sample damage is considerably reduced, easing experimental setup and allowing the investigation of less robust samples. Single-shotmore » X-ray exposures of a streak camera detector using a conventional non-gated charge-coupled device (CCD) camera are also demonstrated.« less

  8. Thermonuclear ignition by Z-pinch X-ray radiation produced by current of an explosive magnetic generator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garanin, S. G.; Ivanovskiy, A. V., E-mail: ivanovsky@elph.vniief.ru

    2015-12-15

    The scheme of a device based a superpower disk-type magnetic explosion generator to produce a pulse of X-ray radiation with the energy exceeding the target ignition threshold is described and validated.

  9. Thermonuclear ignition by Z-pinch X-ray radiation produced by current of an explosive magnetic generator

    NASA Astrophysics Data System (ADS)

    Garanin, S. G.; Ivanovskiy, A. V.

    2015-12-01

    The scheme of a device based a superpower disk-type magnetic explosion generator to produce a pulse of X-ray radiation with the energy exceeding the target ignition threshold is described and validated.

  10. MIXS on BepiColombo and its DEPFET based focal plane instrumentation

    NASA Astrophysics Data System (ADS)

    Treis, J.; Andricek, L.; Aschauer, F.; Heinzinger, K.; Herrmann, S.; Hilchenbach, M.; Lauf, T.; Lechner, P.; Lutz, G.; Majewski, P.; Porro, M.; Richter, R. H.; Schaller, G.; Schnecke, M.; Schopper, F.; Soltau, H.; Stefanescu, A.; Strüder, L.; de Vita, G.

    2010-12-01

    Focal plane instrumentation based on DEPFET Macropixel devices, being a combination of the Detector-Amplifier structure DEPFET with a silicon drift chamber (SDD), has been proposed for the MIXS (Mercury Imaging X-ray Spectrometer) instrument on ESA's Mercury exploration mission BepiColombo. MIXS images X-ray fluorescent radiation from the Mercury surface with a lightweight X-ray mirror system on the focal plane detector to measure the spatially resolved element abundance in Mercury's crust. The sensor needs to have an energy resolution better than 200 eV FWHM at 1 keV and is required to cover an energy range from 0.5 to 10 keV, for a pixel size of 300×300μm2. Main challenges for the instrument are radiation damage and the difficult thermal environment in the mercury orbit. The production of the first batch of flight devices has been finished at the MPI semiconductor laboratory. Prototype modules have been assembled to verify the electrical properties of the devices; selected results are presented here. The prototype devices, Macropixel prototypes for the SIMBOL-X focal plane, are electrically fully compatible, but have a pixel size of 0.5×0.5 mm2. Excellent homogeneity and near Fano-limited energy resolution at high readout speeds have been observed on these devices.

  11. New Energy-Dependent Soft X-Rav Damage In MOS Devices

    NASA Astrophysics Data System (ADS)

    Chan, Tung-Yi; Gaw, Henry; Seligson, Daniel; Pan, Lawrence; King, Paul L.; Pianetta, Piero

    1988-06-01

    An energy-dependent soft x-ray-induced device damage has been discovered in MOS devices fabricated using standard CMOS process. MOS devices were irradiated by monochromatic x-rays in energy range just above and below the silicon K-edge (1.84 keV). Photons below the K-edge is found to create more damage in the oxide and oxide/silicon interface than photons above the K-edge. This energy-dependent damage effect is believed to be due to charge traps generated during device fabrication. It is found that data for both n- and p-type devices lie along a universal curve if normalized threshold voltage shifts are plotted against absorbed dose in the oxide. The threshold voltage shift saturates when the absorbed dose in the oxide exceeds 1.4X105 mJ/cm3, corresponding to 6 Mrad in the oxide. Using isochronal anneals, the trapped charge damage is found to recover with an activation energy of 0.38 eV. A discrete radiation-induced damage state appears in the low frequency C-V curve in a temperature range from 1750C to 325°C.

  12. Pullout strength of cancellous screws in human femoral heads depends on applied insertion torque, trabecular bone microarchitecture and areal bone mineral density.

    PubMed

    Ab-Lazid, Rosidah; Perilli, Egon; Ryan, Melissa K; Costi, John J; Reynolds, Karen J

    2014-12-01

    For cancellous bone screws, the respective roles of the applied insertion torque (TInsert) and of the quality of the host bone (microarchitecture, areal bone mineral density (aBMD)), in contributing to the mechanical holding strength of the bone-screw construct (FPullout), are still unclear. During orthopaedic surgery screws are tightened, typically manually, until adequate compression is attained, depending on surgeons' manual feel. This corresponds to a subjective insertion torque control, and can lead to variable levels of tightening, including screw stripping. The aim of this study, performed on cancellous screws inserted in human femoral heads, was to investigate which, among the measurements of aBMD, bone microarchitecture, and the applied TInsert, has the strongest correlation with FPullout. Forty six femoral heads were obtained, over which microarchitecture and aBMD were evaluated using micro-computed tomography and dual X-ray absorptiometry. Using an automated micro-mechanical test device, a cancellous screw was inserted in the femoral heads at TInsert set to 55% to 99% of the predicted stripping torque beyond screw head contact, after which FPullout was measured. FPullout exhibited strongest correlations with TInsert (R=0.88, p<0.001), followed by structure model index (SMI, R=-0.81, p<0.001), bone volume fraction (BV/TV, R=0.73, p<0.001) and aBMD (R=0.66, p<0.01). Combinations of TInsert with microarchitectural parameters and/or aBMD did not improve the prediction of FPullout. These results indicate that, for cancellous screws, FPullout depends most strongly on the applied TInsert, followed by microarchitecture and aBMD of the host bone. In trabecular bone, screw tightening increases the holding strength of the screw-bone construct. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Assessment of image quality in x-ray radiography imaging using a small plasma focus device

    NASA Astrophysics Data System (ADS)

    Kanani, A.; Shirani, B.; Jabbari, I.; Mokhtari, J.

    2014-08-01

    This paper offers a comprehensive investigation of image quality parameters for a small plasma focus as a pulsed hard x-ray source for radiography applications. A set of images were captured from some metal objects and electronic circuits using a low energy plasma focus at different voltages of capacitor bank and different pressures of argon gas. The x-ray source focal spot of this device was obtained to be about 0.6 mm using the penumbra imaging method. The image quality was studied by several parameters such as image contrast, line spread function (LSF) and modulation transfer function (MTF). Results showed that the contrast changes by variations in gas pressure. The best contrast was obtained at a pressure of 0.5 mbar and 3.75 kJ stored energy. The results of x-ray dose from the device showed that about 0.6 mGy is sufficient to obtain acceptable images on the film. The measurements of LSF and MTF parameters were carried out by means of a thin stainless steel wire 0.8 mm in diameter and the cut-off frequency was obtained to be about 1.5 cycles/mm.

  14. Post-pinch generation of electron beam in a low energy Mather-type plasma focus device

    NASA Astrophysics Data System (ADS)

    Behbahani, R. A.; Aghamir, F. M.; Aghamir

    2013-10-01

    The post-pinch generation of electron beam in a low energy Mather-type plasma focus (PF) device has been investigated. A fast-calibrated Rogowski coil was used to monitor the emission of electron beam. A two-channel diode X-ray spectrometer along with suitable filters provided the records of energy spectrum of X-ray radiation. Single time-period emissions of electron beam with duration of 100 to 20 ns were recorded in the high range of the device operating pressure (0.8-2 mbar). However, in the low range regime (0.2-0.8 mbar), occurrence of single spike electron beam with duration of 150 +/- 50 ns, as well as multi-emission of electrons with duration of 400 +/- 50 ns, was visible. A multi-peak of tube voltage along with multi-time-period radiation of X-rays dominated by copper lines (Cukα and Cukβ) was noticeable in the low-pressure range. The generated electron beam during the post-pinch phase of anomalous resistances is suspected to be the main source of X-ray radiation. This can also be related to the turbulence of the plasma column during the occurrence of anomalous resistances.

  15. X-ray photonic microsystems for the manipulation of synchrotron light

    DOE PAGES

    Mukhopadhyay, D.; Walko, D. A.; Jung, I. W.; ...

    2015-05-05

    In this study, photonic microsystems played an essential role in the development of integrated photonic devices, thanks to their unique spatiotemporal control and spectral shaping capabilities. Similar capabilities to markedly control and manipulate X-ray radiation are highly desirable but practically impossible due to the massive size of the silicon single-crystal optics currently used. Here we show that micromechanical systems can be used as X-ray optics to create and preserve the spatial, temporal and spectral correlation of the X-rays. We demonstrate that, as X-ray reflective optics they can maintain the wavefront properties with nearly 100% reflectivity, and as a dynamic diffractivemore » optics they can generate nanosecond time windows with over 100-kHz repetition rates. Since X-ray photonic microsystems can be easily incorporated into lab-based and next-generation synchrotron X-ray sources, they bring unprecedented design flexibility for future dynamic and miniature X-ray optics for focusing, wavefront manipulation, multicolour dispersion, and pulse slicing.« less

  16. Charge-coupled-device X-ray detector performance model

    NASA Technical Reports Server (NTRS)

    Bautz, M. W.; Berman, G. E.; Doty, J. P.; Ricker, G. R.

    1987-01-01

    A model that predicts the performance characteristics of CCD detectors being developed for use in X-ray imaging is presented. The model accounts for the interactions of both X-rays and charged particles with the CCD and simulates the transport and loss of charge in the detector. Predicted performance parameters include detective and net quantum efficiencies, split-event probability, and a parameter characterizing the effective thickness presented by the detector to cosmic-ray protons. The predicted performance of two CCDs of different epitaxial layer thicknesses is compared. The model predicts that in each device incomplete recovery of the charge liberated by a photon of energy between 0.1 and 10 keV is very likely to be accompanied by charge splitting between adjacent pixels. The implications of the model predictions for CCD data processing algorithms are briefly discussed.

  17. The development and characterization of a first generation carbon nanotube x-ray based microbeam radiation therapy system

    NASA Astrophysics Data System (ADS)

    Hadsell, Michael John, Jr.

    Microbeam radiation therapy (MRT) is a new type of cancer treatment currently being studied at scattered synchrotron sites throughout the world. It has been shown to be capable of ablating aggressive brain tumors in rats while almost completely sparing the surrounding normal tissue. This promising technique has yet to find its way to the clinic, however, because the radiobiological mechanisms behind its efficacy are still largely unknown. This is partly due to the lack of a compact device that could facilitate more large scale research. The challenges inherent to creating a compact device lie within the structure of MRT, which uses parallel arrays of ultra high-dose, orthovoltage, microplanar beams on the order of 100mum thick and separated by four to ten times their width. Because of focal spot limitations, current commercial orthovoltage devices are simply not capable of creating such arrays at dose rates high enough for effective treatment while maintaining the microbeam pattern necessary to retain the high therapeutic ratio of the technique. Therefore, the development of a compact MRT device using carbon nanotube (CNT) cathode based X-ray technology is presented here. CNT cathodes have been shown to be capable of creating novel focal spot arrays on a single anode while being robust enough for long-term use in X-ray tubes. Using these cathodes, an X-ray tube with a single focal line has been created for the delivery of MRT dose distributions in radiobiological studies on small animals. In this work, the development process and final design of this specialized device will be detailed, along with the optimization and stabilization of its use for small animal studies. In addition, a detailed characterization of its final capabilities will be given; including a comprehensive measurement of its X-ray focal line dimensions, a description and evaluation of its collimator alignment and microbeam dimensions, and a full-scale phantom-based quantification of its dosimetric output. Finally, future project directions will be described briefly along with plans for a second generation device. Based on the results of this work, it is the author's belief that compact CNT MRT devices have definite commercialization potential for radiobiological research.

  18. Attenuation of encrustation by self-assembled inorganic fullerene-like nanoparticles

    NASA Astrophysics Data System (ADS)

    Ron, Racheli; Zbaida, David; Kafka, Ilan Z.; Rosentsveig, Rita; Leibovitch, Ilan; Tenne, Reshef

    2014-04-01

    Ureteral stents and urethral catheters are commonly used medical devices for maintaining urinary flow. However, long-term placement (>30 days) of these devices in the urinary tracts is limited by the development of encrustation, a phenomenon that holds a prevalence of 50% within this patient population, resulting in a great deal of morbidity to the patients. Here we report the influence of surface coating of an all-silicone catheter with rhenium-doped fullerene-like molybdenum disulfide (Re:IF-MoS2) nanoparticles on the growth and attachment of in vitro encrustation stones. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRD) analyses indicated a remarkable attenuation in encrustation occupation on the Re:IF-MoS2-coated catheter surfaces compared to neat catheters. The doped nanoparticles displayed a unique tendency to self-assemble into mosaic-like arrangements, modifying the surface to be encrustation-repellent. The mechanism of encrustation retardation on the surface coated catheters is discussed in some detail. The ramification of these results for the clogging of other body indwelling devices is briefly discussed.Ureteral stents and urethral catheters are commonly used medical devices for maintaining urinary flow. However, long-term placement (>30 days) of these devices in the urinary tracts is limited by the development of encrustation, a phenomenon that holds a prevalence of 50% within this patient population, resulting in a great deal of morbidity to the patients. Here we report the influence of surface coating of an all-silicone catheter with rhenium-doped fullerene-like molybdenum disulfide (Re:IF-MoS2) nanoparticles on the growth and attachment of in vitro encrustation stones. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRD) analyses indicated a remarkable attenuation in encrustation occupation on the Re:IF-MoS2-coated catheter surfaces compared to neat catheters. The doped nanoparticles displayed a unique tendency to self-assemble into mosaic-like arrangements, modifying the surface to be encrustation-repellent. The mechanism of encrustation retardation on the surface coated catheters is discussed in some detail. The ramification of these results for the clogging of other body indwelling devices is briefly discussed. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr06231g

  19. Extracting the redox orbitals in Li battery materials with high-resolution x-ray compton scattering spectroscopy.

    PubMed

    Suzuki, K; Barbiellini, B; Orikasa, Y; Go, N; Sakurai, H; Kaprzyk, S; Itou, M; Yamamoto, K; Uchimoto, Y; Wang, Yung Jui; Hafiz, H; Bansil, A; Sakurai, Y

    2015-02-27

    We present an incisive spectroscopic technique for directly probing redox orbitals based on bulk electron momentum density measurements via high-resolution x-ray Compton scattering. Application of our method to spinel Li_{x}Mn_{2}O_{4}, a lithium ion battery cathode material, is discussed. The orbital involved in the lithium insertion and extraction process is shown to mainly be the oxygen 2p orbital. Moreover, the manganese 3d states are shown to experience spatial delocalization involving 0.16±0.05 electrons per Mn site during the battery operation. Our analysis provides a clear understanding of the fundamental redox process involved in the working of a lithium ion battery.

  20. The simulated spectrum of the OGRE X-ray EM-CCD camera system

    NASA Astrophysics Data System (ADS)

    Lewis, M.; Soman, M.; Holland, A.; Lumb, D.; Tutt, J.; McEntaffer, R.; Schultz, T.; Holland, K.

    2017-12-01

    The X-ray astronomical telescopes in use today, such as Chandra and XMM-Newton, use X-ray grating spectrometers to probe the high energy physics of the Universe. These instruments typically use reflective optics for focussing onto gratings that disperse incident X-rays across a detector, often a Charge-Coupled Device (CCD). The X-ray energy is determined from the position that it was detected on the CCD. Improved technology for the next generation of X-ray grating spectrometers has been developed and will be tested on a sounding rocket experiment known as the Off-plane Grating Rocket Experiment (OGRE). OGRE aims to capture the highest resolution soft X-ray spectrum of Capella, a well-known astronomical X-ray source, during an observation period lasting between 3 and 6 minutes whilst proving the performance and suitability of three key components. These three components consist of a telescope made from silicon mirrors, gold coated silicon X-ray diffraction gratings and a camera that comprises of four Electron-Multiplying (EM)-CCDs that will be arranged to observe the soft X-rays dispersed by the gratings. EM-CCDs have an architecture similar to standard CCDs, with the addition of an EM gain register where the electron signal is amplified so that the effective signal-to-noise ratio of the imager is improved. The devices also have incredibly favourable Quantum Efficiency values for detecting soft X-ray photons. On OGRE, this improved detector performance allows for easier identification of low energy X-rays and fast readouts due to the amplified signal charge making readout noise almost negligible. A simulation that applies the OGRE instrument performance to the Capella soft X-ray spectrum has been developed that allows the distribution of X-rays onto the EM-CCDs to be predicted. A proposed optical model is also discussed which would enable the missions minimum success criteria's photon count requirement to have a high chance of being met with the shortest possible observation time. These results are compared to a Chandra observation to show the overall effectiveness of the new technologies. The current optical module is shown to narrowly meet the minimum success conditions whilst the proposed model comfortably demonstrates the effectiveness of the technologies if a larger effective area is provided.

  1. Modelling of TES X-ray Microcalorimeters with a Novel Absorber Design

    NASA Technical Reports Server (NTRS)

    Iyomoto, Naoko; Bandler, Simon; Brefosky, Regis; Brown, Ari; Chervenak, James; Figueroa-Feliciano, Enectali; Finkbeiner, Frederick; Kelley, Richard; Kilbourne, Caroline; Lindeman, Mark; hide

    2007-01-01

    Our development of a novel x-ray absorber design that has enabled the incorporation of high-conductivity electroplated gold into our absorbers has yielded devices that not only have achieved breakthrough performance at 6 keV, but also are extraordinarily well modelled. We have determined device parameters that reproduce complex impedance curves and noise spectra throughout transition. Observed pulse heights, decay time and baseline energy resolution were in good agreement with simulated results using the same parameters. In the presentation, we will show these results in detail and we will also show highlights of the characterization of our gold/bismuth-absorber devices. We will discuss possible improvement of our current devices and expected performance of future devices using the modelling results.

  2. Soft X-ray and XUV imaging with a charge-coupled device /CCD/-based detector

    NASA Technical Reports Server (NTRS)

    Loter, N. G.; Burstein, P.; Krieger, A.; Ross, D.; Harrison, D.; Michels, D. J.

    1981-01-01

    A soft X-ray/XUV imaging camera which uses a thinned, back-illuminated, all-buried channel RCA CCD for radiation sensing has been built and tested. The camera is a slow-scan device which makes possible frame integration if necessary. The detection characteristics of the device have been tested over the 15-1500 eV range. The response was linear with exposure up to 0.2-0.4 erg/sq cm; saturation occurred at greater exposures. Attention is given to attempts to resolve single photons with energies of 1.5 keV.

  3. X-ray source characteristics and detection efficiencies of prototype Lixiscopes

    NASA Technical Reports Server (NTRS)

    Seltzer, S. M.

    1978-01-01

    The radioactive X-ray sources and scintillator screens used in prototype Lixiscope units are described. Some of those considerations necessary for the optimization of future Lixiscope designs are stressed as well as some semi-quantitative information on the present prototype devices.

  4. An X-Band SOS Resistive Gate-Insulator-Semiconductor /RIS/ switch

    NASA Astrophysics Data System (ADS)

    Kwok, S. P.

    1980-02-01

    The new X-Band Resistive Gate-Insulator-Semiconductor (RIS) switch has been fabricated on silicon-on-sapphire, and its equivalent circuit model characterized. An RIS SPST switch with 20-dB on/off isolation, 1.2-dB insertion loss, and power handling capacity in excess of 20-W peak has been achieved at X band. The device switching time is on the order of 600 ns, and it requires negligible control holding current in both on and off states. The device is compatible with monolithic integrated-circuit technology and thus is suitable for integration into low-cost monolithic phase shifters or other microwave integrated circuits.

  5. Initial steps toward the realization of large area arrays of single photon counting pixels based on polycrystalline silicon TFTs

    NASA Astrophysics Data System (ADS)

    Liang, Albert K.; Koniczek, Martin; Antonuk, Larry E.; El-Mohri, Youcef; Zhao, Qihua; Jiang, Hao; Street, Robert A.; Lu, Jeng Ping

    2014-03-01

    The thin-film semiconductor processing methods that enabled creation of inexpensive liquid crystal displays based on amorphous silicon transistors for cell phones and televisions, as well as desktop, laptop and mobile computers, also facilitated the development of devices that have become ubiquitous in medical x-ray imaging environments. These devices, called active matrix flat-panel imagers (AMFPIs), measure the integrated signal generated by incident X rays and offer detection areas as large as ~43×43 cm2. In recent years, there has been growing interest in medical x-ray imagers that record information from X ray photons on an individual basis. However, such photon counting devices have generally been based on crystalline silicon, a material not inherently suited to the cost-effective manufacture of monolithic devices of a size comparable to that of AMFPIs. Motivated by these considerations, we have developed an initial set of small area prototype arrays using thin-film processing methods and polycrystalline silicon transistors. These prototypes were developed in the spirit of exploring the possibility of creating large area arrays offering single photon counting capabilities and, to our knowledge, are the first photon counting arrays fabricated using thin film techniques. In this paper, the architecture of the prototype pixels is presented and considerations that influenced the design of the pixel circuits, including amplifier noise, TFT performance variations, and minimum feature size, are discussed.

  6. Combining experiment and optical simulation in coherent X-ray nanobeam characterization of Si/SiGe semiconductor heterostructures

    DOE PAGES

    Tilka, J. A.; Park, J.; Ahn, Y.; ...

    2016-07-06

    Here, the highly coherent and tightly focused x-ray beams produced by hard x-ray light sources enable the nanoscale characterization of the structure of electronic materials but are accompanied by significant challenges in the interpretation of diffraction and scattering patterns. X-ray nanobeams exhibit optical coherence combined with a large angular divergence introduced by the x-ray focusing optics. The scattering of nanofocused x-ray beams from intricate semiconductor heterostructures produces a complex distribution of scattered intensity. We report here an extension of coherent xray optical simulations of convergent x-ray beam diffraction patterns to arbitrary x-ray incident angles to allow the nanobeam diffraction patternsmore » of complex heterostructures to be simulated faithfully. These methods are used to extract the misorientation of lattice planes and the strain of individual layers from synchrotron x-ray nanobeam diffraction patterns of Si/SiGe heterostructures relevant to applications in quantum electronic devices. The systematic interpretation of nanobeam diffraction patterns from semiconductor heterostructures presents a new opportunity in characterizing and ultimately designing electronic materials.« less

  7. Characterization and development of an event-driven hybrid CMOS x-ray detector

    NASA Astrophysics Data System (ADS)

    Griffith, Christopher

    2015-06-01

    Hybrid CMOS detectors (HCD) have provided great benefit to the infrared and optical fields of astronomy, and they are poised to do the same for X-ray astronomy. Infrared HCDs have already flown on the Hubble Space Telescope and the Wide-Field Infrared Survey Explorer (WISE) mission and are slated to fly on the James Webb Space Telescope (JWST). Hybrid CMOS X-ray detectors offer low susceptibility to radiation damage, low power consumption, and fast readout time to avoid pile-up. The fast readout time is necessary for future high throughput X-ray missions. The Speedster-EXD X-ray HCD presented in this dissertation offers new in-pixel features and reduces known noise sources seen on previous generation HCDs. The Speedster-EXD detector makes a great step forward in the development of these detectors for future space missions. This dissertation begins with an overview of future X-ray space mission concepts and their detector requirements. The background on the physics of semiconductor devices and an explanation of the detection of X-rays with these devices will be discussed followed by a discussion on CCDs and CMOS detectors. Next, hybrid CMOS X-ray detectors will be explained including their advantages and disadvantages. The Speedster-EXD detector and its new features will be outlined including its ability to only read out pixels which contain X-ray events. Test stand design and construction for the Speedster-EXD detector is outlined and the characterization of each parameter on two Speedster-EXD detectors is detailed including read noise, dark current, interpixel capacitance crosstalk (IPC), and energy resolution. Gain variation is also characterized, and a Monte Carlo simulation of its impact on energy resolution is described. This analysis shows that its effect can be successfully nullified with proper calibration, which would be important for a flight mission. Appendix B contains a study of the extreme tidal disruption event, Swift J1644+57, to search for periodicities in its X-ray light curve. iii.

  8. Flat field anomalies in an x-ray charge coupled device camera measured using a Manson x-ray source

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haugh, M. J.; Schneider, M. B.

    2008-10-15

    The static x-ray imager (SXI) is a diagnostic used at the National Ignition Facility (NIF) to measure the position of the x rays produced by lasers hitting a gold foil target. The intensity distribution taken by the SXI camera during a NIF shot is used to determine how accurately NIF can aim laser beams. This is critical to proper NIF operation. Imagers are located at the top and the bottom of the NIF target chamber. The charge coupled device (CCD) chip is an x-ray sensitive silicon sensor, with a large format array (2kx2k), 24 {mu}m square pixels, and 15 {mu}mmore » thick. A multianode Manson x-ray source, operating up to 10 kV and 10 W, was used to characterize and calibrate the imagers. The output beam is heavily filtered to narrow the spectral beam width, giving a typical resolution E/{delta}E{approx_equal}10. The x-ray beam intensity was measured using an x-ray photodiode that has an accuracy better than 1% up to the Si K edge and better than 5% at higher energies. The x-ray beam provides full CCD illumination and is flat, within {+-}1% maximum to minimum. The spectral efficiency was measured at ten energy bands ranging from 930 to 8470 eV. We observed an energy dependent pixel sensitivity variation that showed continuous change over a large portion of the CCD. The maximum sensitivity variation occurred at 8470 eV. The geometric pattern did not change at lower energies, but the maximum contrast decreased and was not observable below 4 keV. We were also able to observe debris, damage, and surface defects on the CCD chip. The Manson source is a powerful tool for characterizing the imaging errors of an x-ray CCD imager. These errors are quite different from those found in a visible CCD imager.« less

  9. Development of a CCD array as an imaging detector for advanced X-ray astrophysics facilities

    NASA Technical Reports Server (NTRS)

    Schwartz, D. A.

    1981-01-01

    The development of a charge coupled device (CCD) X-ray imager for a large aperture, high angular resolution X-ray telescope is discussed. Existing CCDs were surveyed and three candidate concepts were identified. An electronic camera control and computer interface, including software to drive a Fairchild 211 CCD, is described. In addition a vacuum mounting and cooling system is discussed. Performance data for the various components are given.

  10. Topological Insulators and Superconductors for Innovative Devices

    DTIC Science & Technology

    2015-03-20

    bulk-sensitive experiment with hard x ray or low-energy photons.) This demon- strates that the bulk band gap can be enhanced by taking advantage of the...crystallinity in X - ray Laue analysis, and their detailed transport properties are described in the Supplementary Information. ARPES measurements were...high quality of our fi lms grown at high temperatures, including ultrathin ones, is evident from the X - ray diffraction patterns shown in Figure 2 d

  11. Spectral CT of the extremities with a silicon strip photon counting detector

    NASA Astrophysics Data System (ADS)

    Sisniega, A.; Zbijewski, W.; Stayman, J. W.; Xu, J.; Taguchi, K.; Siewerdsen, J. H.

    2015-03-01

    Purpose: Photon counting x-ray detectors (PCXDs) are an important emerging technology for spectral imaging and material differentiation with numerous potential applications in diagnostic imaging. We report development of a Si-strip PCXD system originally developed for mammography with potential application to spectral CT of musculoskeletal extremities, including challenges associated with sparse sampling, spectral calibration, and optimization for higher energy x-ray beams. Methods: A bench-top CT system was developed incorporating a Si-strip PCXD, fixed anode x-ray source, and rotational and translational motions to execute complex acquisition trajectories. Trajectories involving rotation and translation combined with iterative reconstruction were investigated, including single and multiple axial scans and longitudinal helical scans. The system was calibrated to provide accurate spectral separation in dual-energy three-material decomposition of soft-tissue, bone, and iodine. Image quality and decomposition accuracy were assessed in experiments using a phantom with pairs of bone and iodine inserts (3, 5, 15 and 20 mm) and an anthropomorphic wrist. Results: The designed trajectories improved the sampling distribution from 56% minimum sampling of voxels to 75%. Use of iterative reconstruction (viz., penalized likelihood with edge preserving regularization) in combination with such trajectories resulted in a very low level of artifacts in images of the wrist. For large bone or iodine inserts (>5 mm diameter), the error in the estimated material concentration was <16% for (50 mg/mL) bone and <8% for (5 mg/mL) iodine with strong regularization. For smaller inserts, errors of 20-40% were observed and motivate improved methods for spectral calibration and optimization of the edge-preserving regularizer. Conclusion: Use of PCXDs for three-material decomposition in joint imaging proved feasible through a combination of rotation-translation acquisition trajectories and iterative reconstruction with optimized regularization.

  12. Engineering Encodable Lanthanide-Binding Tags (LBTs) into Loop Regions of Proteins

    PubMed Central

    Barthelmes, Katja; Reynolds, Anne M.; Peisach, Ezra; Jonker, Hendrik R. A.; DeNunzio, Nicholas J.; Allen, Karen N.; Imperiali, Barbara; Schwalbe, Harald

    2011-01-01

    Lanthanide-binding-tags (LBTs) are valuable tools for investigation of protein structure, function, and dynamics by NMR spectroscopy, X-ray crystallography and luminescence studies. We have inserted LBTs into three different loop positions (denoted L, R, and S) of the model protein interleukin-1β and varied the length of the spacer between the LBT and the protein (denoted 1-3). Luminescence studies demonstrate that all nine constructs bind Tb3+ tightly in the low nanomolar range. No significant change in the fusion protein occurs from insertion of the LBT, as shown by two X-ray crystallographic structures of the IL1β-S1 and IL1β-L3 constructs and for the remaining constructs by comparing 1H-15N-HSQC NMR spectra with wild-type IL1β. Additionally, binding of LBT-loop IL1β proteins to their native binding partner in vitro remains unaltered. X-ray crystallographic phasing was successful using only the signal from the bound lanthanide. Large residual dipolar couplings (RDCs) could be determined by NMR spectroscopy for all LBT-loop-constructs and revealed that the LBT-2 series were rigidly incorporated into the interleukin-1β structure. The paramagnetic NMR spectra of loop-LBT mutant IL1β-R2 were assigned and the Δχ tensor components were calculated based on RDCs and pseudocontact shifts (PCSs). A structural model of the IL1β-R2 construct was calculated using the paramagnetic restraints. The current data provide support that encodable LBTs serve as versatile biophysical tags when inserted into loop regions of proteins of known structure or predicted via homology modelling. PMID:21182275

  13. Apparatus for X-ray diffraction microscopy and tomography of cryo specimens

    DOE PAGES

    Beetz, T.; Howells, M. R.; Jacobsen, C.; ...

    2005-03-14

    An apparatus for diffraction microscopy of biological and materials science specimens is described. In this system, a coherent soft X-ray beam is selected with a pinhole, and the illuminated specimen is followed by an adjustable beamstop and CCD camera to record diffraction data from non-crystalline specimens. In addition, a Fresnel zone plate can be inserted to allow for direct imaging. The system makes use of a cryogenic specimen holder with cryotransfer capabilities to allow frozen hydrated specimens to be loaded. The specimen can be tilted over a range of ± 80 ° degrees for three-dimensional imaging; this is done bymore » computer-controlled motors, enabling automated alignment of the specimen through a tilt series. The system is now in use for experiments in soft X-ray diffraction microscopy.« less

  14. An abuttable CCD imager for visible and X-ray focal plane arrays

    NASA Technical Reports Server (NTRS)

    Burke, Barry E.; Mountain, Robert W.; Harrison, David C.; Bautz, Marshall W.; Doty, John P.

    1991-01-01

    A frame-transfer silicon charge-coupled-device (CCD) imager has been developed that can be closely abutted to other imagers on three sides of the imaging array. It is intended for use in multichip arrays. The device has 420 x 420 pixels in the imaging and frame-store regions and is constructed using a three-phase triple-polysilicon process. Particular emphasis has been placed on achieving low-noise charge detection for low-light-level imaging in the visible and maximum energy resolution for X-ray spectroscopic applications. Noise levels of 6 electrons at 1-MHz and less than 3 electrons at 100-kHz data rates have been achieved. Imagers have been fabricated on 1000-Ohm-cm material to maximize quantum efficiency and minimize split events in the soft X-ray regime.

  15. Thermal analysis on x-ray tube for exhaust process

    NASA Astrophysics Data System (ADS)

    Kumar, Rakesh; Rao Ratnala, Srinivas; Veeresh Kumar, G. B.; Shivakumar Gouda, P. S.

    2018-02-01

    It is great importance in the use of X-rays for medical purposes that the dose given to both the patient and the operator is carefully controlled. There are many types of the X- ray tubes used for different applications based on their capacity and power supplied. In present thesis maxi ray 165 tube is analysed for thermal exhaust processes with ±5% accuracy. Exhaust process is usually done to remove all the air particles and to degasify the insert under high vacuum at 2e-05Torr. The tube glass is made up of Pyrex material, 95%Tungsten and 5%rhenium is used as target material for which the melting point temperature is 3350°C. Various materials are used for various parts; during the operation of X- ray tube these waste gases are released due to high temperature which in turn disturbs the flow of electrons. Thus, before using the X-ray tube for practical applications it has to undergo exhaust processes. Initially we build MX 165 model to carry out thermal analysis, and then we simulate the bearing temperature profiles with FE model to match with test results with ±5%accuracy. At last implement the critical protocols required for manufacturing processes like MF Heating, E-beam, Seasoning and FT.

  16. Cone-beam computed tomography in children with cochlear implants: The effect of electrode array position on ECAP.

    PubMed

    Lathuillière, Marine; Merklen, Fanny; Piron, Jean-Pierre; Sicard, Marielle; Villemus, Françoise; Menjot de Champfleur, Nicolas; Venail, Frédéric; Uziel, Alain; Mondain, Michel

    2017-01-01

    To assess the feasibility of using cone-beam computed tomography (CBCT) in young children with cochlear implants (CIs) and study the effect of intracochlear position on electrophysiological and behavioral measurements. A total of 40 children with either unilateral or bilateral cochlear implants were prospectively included in the study. Electrode placement and insertion angles were studied in 55 Cochlear ® implants (16 straight arrays and 39 perimodiolar arrays), using either CBCT or X-ray imaging. CBCT or X-ray imaging were scheduled when the children were leaving the recovery room. We recorded intraoperative and postoperative neural response telemetry threshold (T-NRT) values, intraoperative and postoperative electrode impedance values, as well as behavioral T (threshold) and C (comfort) levels on electrodes 1, 5, 10, 15 and 20. CBCT imaging was feasible without any sedation in 24 children (60%). Accidental scala vestibuli insertion was observed in 3 out of 24 implants as assessed by CBCT. The mean insertion angle was 339.7°±35.8°. The use of a perimodiolar array led to higher angles of insertion, lower postoperative T-NRT, as well as decreased behavioral T and C levels. We found no significant effect of either electrode array position or angle of insertion on electrophysiological data. CBCT appears to be a reliable tool for anatomical assessment of young children with CIs. Intracochlear position had no significant effect on the electrically evoked compound action potential (ECAP) threshold. Our CBCT protocol must be improved to increase the rate of successful investigations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. Services of the CDRH X-ray calibration laboratory and their traceability to National Standards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cerra, F.; Heaton, H.T.

    The X-ray Calibration Laboratory (XCL) of the Center for Devices and Radiological Health (CDRH) provides calibration services for the Food and Drug Administration (FDA). The instruments calibrated are used by FDA and contract state inspectors to verify compliance with federal x-ray performance standards and for national surveys of x-ray trends. In order to provide traceability of measurements, the CDRH XCL is accredited by the National Voluntary Laboratory Accreditation Program (NVLAP) for reference, diagnostic, and x-ray survey instrument calibrations. In addition to these accredited services, the CDRH XCL also calibrates non-invasive kVp meters in single- and three-phase x-ray beams, and thermoluminescentmore » dosimeter (TLD) chips used to measure CT beam profiles. The poster illustrates these services and shows the traceability links back to the National Standards.« less

  18. Tests of monolithic active pixel sensors at national synchrotron light source

    NASA Astrophysics Data System (ADS)

    Deptuch, G.; Besson, A.; Carini, G. A.; Siddons, D. P.; Szelezniak, M.; Winter, M.

    2007-01-01

    The paper discusses basic characterization of Monolithic Active Pixel Sensors (MAPS) carried out at the X12A beam-line at National Synchrotron Light Source (NSLS), Upton, NY, USA. The tested device was a MIMOSA V (MV) chip, back-thinned down to the epitaxial layer. This 1M pixels device features a pixel size of 17×17 μm2 and was designed in a 0.6 μm CMOS process. The X-ray beam energies used range from 5 to 12 keV. Examples of direct X-ray imaging capabilities are presented.

  19. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... of x-radiation into a visible image. This generic type of device may include signal analysis and...

  20. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... of x-radiation into a visible image. This generic type of device may include signal analysis and...

  1. 21 CFR 892.1660 - Non-image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Non-image-intensified fluoroscopic x-ray system. 892.1660 Section 892.1660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... of x-radiation into a visible image. This generic type of device may include signal analysis and...

  2. Detector for CheMin

    NASA Image and Video Library

    2012-10-30

    This charged couple device CCD is part of the CheMin instrument on NASA Curiosity rover. When CheMin directs X-rays at a sample of soil, this imager, which is the size of a postage stamp, detects both the position and energy of each X-ray photon.

  3. An all-diamond X-ray position and flux monitor using nitrogen-incorporated ultra-nanocrystalline diamond contacts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zou, Mengnan; Gaowei, Mengjia; Zhou, Tianyi

    Diamond X-ray detectors with conducting nitrogen-incorporated ultra-nanocrystalline diamond (N-UNCD) films as electrodes were fabricated to measure X-ray beam flux and position. Structural characterization and functionality tests were performed for these devices. The N-UNCD films grown on unseeded diamond substrates were compared with N-UNCD films grown on a seeded silicon substrate. The feasibility of the N-UNCD films acting as electrodes for X-ray detectors was confirmed by the stable performance in a monochromatic X-ray beam. The fabrication process is able to change the surface status which may influence the signal uniformity under low bias, but this effect can be neglected under fullmore » collection bias.« less

  4. Comparison of simulated and measured spectra from an X-ray tube for the energies between 20 and 35 keV

    NASA Astrophysics Data System (ADS)

    Yücel, M.; Emirhan, E.; Bayrak, A.; Ozben, C. S.; Yücel, E. Barlas

    2015-11-01

    Design and production of a simple and low cost X-ray imaging system that can be used for light industrial applications was targeted in the Nuclear Physics Laboratory of Istanbul Technical University. In this study, production, transmission and detection of X-rays were simulated for the proposed imaging device. OX/70-P dental tube was used and X-ray spectra simulated by Geant4 were validated by comparison with X-ray spectra measured between 20 and 35 keV. Relative detection efficiency of the detector was also determined to confirm the physics processes used in the simulations. Various time optimization tools were performed to reduce the simulation time.

  5. Thermal detectors as single photon X-ray spectrometers

    NASA Technical Reports Server (NTRS)

    Moseley, S. H.; Kelley, R. L.; Mather, J. C.; Mushotzky, R. F.; Szymkowiak, A. E.; Mccammon, D.

    1985-01-01

    In a thermal detector employed for X-ray spectroscopy applications, the energy of an X-ray is converted to heat in a small mass, and the energy of that X-ray inferred from the size of the temperature rise. The present investigation is concerned with the possibility to make an extremely low heat capacity calorimeter which can be employed as a thermal detector. Several types of calorimeters were fabricated and tested at temperatures as low as approximately 0.05 K. The obtained devices make use of thermistors constructed of melt-doped silicon, nuclear transmutation doped (NTD) germanium, and ion-implanted silicon with a variety of materials for the support and electrical leads. The utility of these microcalorimeters as X-ray spectrometers could be verified.

  6. Prototype high resolution multienergy soft x-ray array for NSTX.

    PubMed

    Tritz, K; Stutman, D; Delgado-Aparicio, L; Finkenthal, M; Kaita, R; Roquemore, L

    2010-10-01

    A novel diagnostic design seeks to enhance the capability of multienergy soft x-ray (SXR) detection by using an image intensifier to amplify the signals from a larger set of filtered x-ray profiles. The increased number of profiles and simplified detection system provides a compact diagnostic device for measuring T(e) in addition to contributions from density and impurities. A single-energy prototype system has been implemented on NSTX, comprised of a filtered x-ray pinhole camera, which converts the x-rays to visible light using a CsI:Tl phosphor. SXR profiles have been measured in high performance plasmas at frame rates of up to 10 kHz, and comparisons to the toroidally displaced tangential multi-energy SXR have been made.

  7. Co-complexes Derived from Alkene Insertion to Alkyne-dicobaltpentacarbonyl complexes: Insight into the Regioselectivity of Pauson-Khand Reactions of Cyclopropenes

    PubMed Central

    Pallerla, Mahesh K.; Yap, Glenn P. A.; Fox, Joseph M.

    2009-01-01

    Described are the X-ray crystallographic and spectral properties of Co-complexes that were isolated from two Pauson-Khand reactions of chiral cyclopropenes. These are the first examples of isolated Co-complexes derived from the putative alkene-insertion intermediates of Pauson-Khand reactions. The binuclear Co-complexes are coordinated to μ-bonded, five-carbon “flyover” carbene ligands. It is proposed that the complexes result from cyclopropane fragmentation subsequent to alkene insertion. The observation of these metal complexes provides a rationale for the origin of regioselectivity in Pauson-Khand reactions of cyclopropenes. PMID:18637694

  8. X-Ray Structure determination of the Glycine Cleavage System Protein H of Mycobacterium tuberculosis Using An Inverse Compton Synchrotron X-Ray Source

    PubMed Central

    Abendroth, Jan; McCormick, Michael S.; Edwards, Thomas E.; Staker, Bart; Loewen, Roderick; Gifford, Martin; Rifkin, Jeff; Mayer, Chad; Guo, Wenjin; Zhang, Yang; Myler, Peter; Kelley, Angela; Analau, Erwin; Hewitt, Stephen Nakazawa; Napuli, Alberto J.; Kuhn, Peter; Ruth, Ronald D.; Stewart, Lance J.

    2010-01-01

    Structural genomics discovery projects require ready access to both X-ray and NMR instrumentation which support the collection of experimental data needed to solve large numbers of novel protein structures. The most productive X-ray crystal structure determination laboratories make extensive frequent use of tunable synchrotron X-ray light to solve novel structures by anomalous diffraction methods. This requires that frozen cryo-protected crystals be shipped to large government-run synchrotron facilities for data collection. In an effort to eliminate the need to ship crystals for data collection, we have developed the first laboratory-scale synchrotron light source capable of performing many of the state-of-the-art synchrotron applications in X-ray science. This Compact Light Source is a first-in-class device that uses inverse Compton scattering to generate X-rays of sufficient flux, tunable wavelength and beam size to allow high-resolution X-ray diffraction data collection from protein crystals. We report on benchmarking tests of X-ray diffraction data collection with hen egg white lysozyme, and the successful high-resolution X-ray structure determination of the Glycine cleavage system protein H from Mycobacterium tuberculosis using diffraction data collected with the Compact Light Source X-ray beam. PMID:20364333

  9. An alignment method for mammographic X-ray spectroscopy under clinical conditions.

    PubMed

    Miyajima, S; Imagawa, K; Matsumoto, M

    2002-09-01

    This paper describes an alignment method for mammographic X-ray spectroscopy under clinical conditions. A pinhole, a fluorescent screen, a laser device and the case for a detector are used for alignment of the focal spot, a collimator and a detector. The method determines the line between the focal spot and the point of interest in an X-ray field radiographically. The method allows alignment for both central axis and off-axis directions.

  10. Exploring interface morphology of a deeply buried layer in periodic multilayer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Das, Gangadhar; Srivastava, A. K.; Tiwari, M. K., E-mail: mktiwari@rrcat.gov.in

    2016-06-27

    Long-term durability of a thin film device is strongly correlated with the nature of interface structure associated between different constituent layers. Synthetic periodic multilayer structures are primarily employed as artificial X-ray Bragg reflectors in many applications, and their reflection efficiency is predominantly dictated by the nature of the buried interfaces between the different layers. Herein, we demonstrate the applicability of the combined analysis approach of the X-ray reflectivity and grazing incidence X-ray fluorescence measurements for the reliable and precise determination of a buried interface structure inside periodic X-ray multilayer structures. X-ray standing wave field (XSW) generated under Bragg reflection conditionmore » is used to probe the different constituent layers of the W- B{sub 4}C multilayer structure at 10 keV and 12 keV incident X-ray energies. Our results show that the XSW assisted fluorescence measurements are markedly sensitive to the location and interface morphology of a buried layer structure inside a periodic multilayer structure. The cross sectional transmission electron microscopy results obtained on the W-B{sub 4}C multilayer structure provide a deeper look on the overall reliability and accuracy of the XSW method. The method described here would also be applicable for nondestructive characterization of a wide range of thin film based semiconductor and optical devices.« less

  11. Advanced Small Animal Conformal Radiation Therapy Device.

    PubMed

    Sharma, Sunil; Narayanasamy, Ganesh; Przybyla, Beata; Webber, Jessica; Boerma, Marjan; Clarkson, Richard; Moros, Eduardo G; Corry, Peter M; Griffin, Robert J

    2017-02-01

    We have developed a small animal conformal radiation therapy device that provides a degree of geometrical/anatomical targeting comparable to what is achievable in a commercial animal irradiator. small animal conformal radiation therapy device is capable of producing precise and accurate conformal delivery of radiation to target as well as for imaging small animals. The small animal conformal radiation therapy device uses an X-ray tube, a robotic animal position system, and a digital imager. The system is in a steel enclosure with adequate lead shielding following National Council on Radiation Protection and Measurements 49 guidelines and verified with Geiger-Mueller survey meter. The X-ray source is calibrated following AAPM TG-61 specifications and mounted at 101.6 cm from the floor, which is a primary barrier. The X-ray tube is mounted on a custom-made "gantry" and has a special collimating assembly system that allows field size between 0.5 mm and 20 cm at isocenter. Three-dimensional imaging can be performed to aid target localization using the same X-ray source at custom settings and an in-house reconstruction software. The small animal conformal radiation therapy device thus provides an excellent integrated system to promote translational research in radiation oncology in an academic laboratory. The purpose of this article is to review shielding and dosimetric measurement and highlight a few successful studies that have been performed to date with our system. In addition, an example of new data from an in vivo rat model of breast cancer is presented in which spatially fractionated radiation alone and in combination with thermal ablation was applied and the therapeutic benefit examined.

  12. Synthesis and characterization of organic/inorganic heterostructure films for hybrid light emitting diode

    NASA Astrophysics Data System (ADS)

    Toyama, Toshihiko; Ichihara, Tokuyuki; Yamaguchi, Daisuke; Okamoto, Hiroaki

    2007-10-01

    Thin-film light emitting devices based on organic materials have been gathering attentions for applying a flat-panel display and a solid-state lighting. Alternatively, inorganic technologies such as Si-based thin-film technology have been growing almost independently. It is then expected that combining the Si-based thin-film technology with the organic light emitting diode (OLED) technology will develop innovative devices. Here, we report syntheses of the hybrid light emitting diode (LED) with a heterostructure consisting of p-type SiC x and tris-(8-hydroxyquinoline) aluminum films and characterization for the hybrid LEDs. We present the energy diagram of the heterostructure, and describe that the use of high dark conductivities of the p-type SiC x as well as inserting wide-gap intrinsic a-SiC x at the p-type SiC x/Alq interface are effective for improving device performance.

  13. Mechanism of Me–Re Bond Addition to Platinum(II) and Dioxygen Activation by the Resulting Pt–Re Bimetallic Center

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pichaandi, Kothanda Rama; Kabalan, Lara; Amini, Hashem

    Unusual cis-oxidative addition of methyltrioxorhenium (MTO) to [PtMe 2(bpy)], (bpy = 2,2'-bipyridine) (1) is described. Addition of MTO to 1 first gives the Lewis acid–base adduct [(bpy)Me 2Pt–Re(Me)(O) 3] (2) and subsequently affords the oxidative addition product [(bpy)Me 3PtReO 3] (3). All complexes 1, MTO, 2, and 3 are in equilibrium in solution. The structure of 2 was confirmed by X-ray crystallography, and its dissociation constant in solution is 0.87 M. The structure of 3 was confirmed by extended X-ray absorption fine structure and X-ray absorption near-edge structure in tandem with one- and two-dimensional NMR spectroscopy augmented by deuterium andmore » 13C isotope-labeling studies. Kinetics of formation of compound 3 revealed saturation kinetics dependence on [MTO] and first-order in [Pt], complying with prior equilibrium formation of 2 with oxidative addition of Me–Re being the rate-determining step. Exposure of 3 to molecular oxygen or air resulted in the insertion of an oxygen atom into the platinum–rhenium bond forming [(bpy)Me 3PtOReO 3] (4) as final product. In conclusion, density functional theory analysis on oxygen insertion pathways leading to complex 4, merited on the basis of Russell oxidation pathway, revealed the involvement of rhenium peroxo species.'« less

  14. Lithium Metal-Copper Vanadium Oxide Battery with a Block Copolymer Electrolyte

    DOE PAGES

    Devaux, Didier; Wang, Xiaoya; Thelen, Jacob L.; ...

    2016-09-08

    Lithium (Li) batteries comprising multivalent positive active materials such as copper vanadium oxide have high theoretical capacity. These batteries with a conventional liquid electrolyte exhibit limited cycle life because of copper dissolution into the electrolyte. In this paper, we report here on the characterization of solid-state Li metal batteries with a positive electrode based on α-Cu 6.9V 6O 18.9 (α-CuVO 3). We replaced the liquid electrolyte by a nanostructured solid block copolymer electrolyte comprising of a mixture of polystyrene-b-poly(ethylene oxide) (SEO) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. In situ X-ray diffraction was used to follow the Li insertion/de-insertion mechanism into themore » α-CuVO 3 host material and its reversibility. In situ X-ray scattering revealed that the multistep electrochemical reactions involved are similar in the presence of liquid or solid electrolyte. The capacity fade of the solid-state batteries is less rapid than that of α-CuVO 3–Li metal batteries with a conventional liquid electrolyte. Hard X-ray microtomography revealed that upon cycling, voids and Cu-rich agglomerates were formed at the interface between the Li metal and the SEO electrolyte. Finally, the void volume and the volume occupied by the Cu-rich agglomerates were independent of C-rate and cycle number.« less

  15. Linking structural biology with genome research: Beamlines for the Berlin ``Protein Structure Factory'' initiative

    NASA Astrophysics Data System (ADS)

    Illing, Gerd; Saenger, Wolfram; Heinemann, Udo

    2000-06-01

    The Protein Structure Factory will be established to characterize proteins encoded by human genes or cDNAs, which will be selected by criteria of potential structural novelty or medical or biotechnological usefulness. It represents an integrative approach to structure analysis combining bioinformatics techniques, automated gene expression and purification of gene products, generation of a biophysical fingerprint of the proteins and the determination of their three-dimensional structures either by NMR spectroscopy or by X-ray diffraction. The use of synchrotron radiation will be crucial to the Protein Structure Factory: high brilliance and tunable wavelengths are prerequisites for fast data collection, the use of small crystals and multiwavelength anomalous diffraction (MAD) phasing. With the opening of BESSY II, direct access to a third-generation XUV storage ring source with excellent conditions is available nearby. An insertion device with two MAD beamlines and one constant energy station will be set up until 2001.

  16. ANKA, a customer-oriented synchrotron radiation facility for microfabrication and analytical services

    NASA Astrophysics Data System (ADS)

    Pea Anka Project Group; Buth, G.; Doyle, S.; Einfeld, D.; Hagelstein, M.; Hermle, S.; Huttel, E.; Krüssel, A.; Lange, M.; Mathis, Y.-L.; Mexner, W.; Moser, H. O.; Pellegrin, E.; Ristau, U.; Rossmanith, R.; Schaper, J.; Schieler, H.; Simon, R.; Steininger, R.; Voigt, S.; Walther, R.; Perez, F.; Pont, M.; Plesko, M.

    1998-03-01

    ANKA (Angströmquelle Karlsruhe) is a state-of-the-art synchrotron radiation facility under construction at the Forschungszentrum Karlsruhe. Based on a 2.5 GeV electron storage ring it will deliver photons predominantly in the hard X-ray range but it will also feature both XUV and infrared beamlines. In its first operational phase the radiation will be taken out of normal-conducting dipole bending magnets, while five free long straight sections are foreseen to accommodate insertion devices later on. ANKA has a novel mission, namely to provide synchrotron-radiation based services to industrial and other customers, in the fields of microfabrication and materials analysis. A limited liability company, ANKA GmbH, is being founded to operate the facility. Although commercial services to customers will represent more than half of the overall activity, these services will be complemented by providing beam time for research users.

  17. Status of the SAGA Light Source

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kaneyasu, T.; Takabayashi, Y.; Iwasaki, Y.

    The SAGA Light Source (SAGA-LS) is a synchrotron radiation facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring that is 75.6 m in circumference. The SAGA-LS has been stably providing synchrotron radiation to users since it first started user operation in February 2006. Along with the user operation, various machine improvements have been made over the past years, including upgrading the injector linac control system, replacing a septum magnet and constructing a beam diagnostic system. In addition to these improvements, insertion devices have been developed and installed. An APPLE-II type variable polarization undulator was installedmore » in 2008. To address the demand from users for high-flux hard x-rays, a superconducting 4 T class wiggler is being developed. An experimental setup for generating MeV photons by laser Compton scattering is being constructed for beam monitoring and future user experiments.« less

  18. The EUTERPE facility

    NASA Astrophysics Data System (ADS)

    Botman, J. I. M.; Xi, Boling; Timmermans, C. J.; Hagedoorn, H. L.

    1992-01-01

    The 400-MeV electron storage ring EUTERPE is a University project set up for studies of charged particle beam dynamics and applications of synchrotron radiation, and for the education of students in these fields. The ring has a relatively large circumference for the maximum beam energy contained, which is useful for accommodating insertion devices and diagnostic tools. The critical wavelength of the emitted photon spectrum is 8.3 nm for the regular dipole magnets and 1.2 nm corresponding to 1.03 keV for a 10-T wiggler. This provides useful radiation, e.g., for x-ray fluorescence up to 3.2 keV. An undulator with a periodicity distance of 2.5 cm is planned, to generate radiation of 40 nm. The major ring components are being constructed in the University workshop, including a 70-MeV injector microtron. The main characteristics of the machine and the present status are reported. Future options include a bypass system for microdevices.

  19. Toward operation of series IDs at BL43LXU of SPring-8

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baron, A. Q. R.; Tanaka, T.; Soutome, K.

    2016-07-27

    This paper discusses two issues relating to using 3 small gap insertion devices in series at BL43LXU of SPring-8 to make a uniquely powerful source in the 15-26 keV region of the x-ray spectrum. The issues discussed are (1) damage to the covers of the downstream IDs by radiation from the upstream IDs and (2) proper steering of the electron beam to get the best photon beam properties. After tests in several configurations, including one where an ID was run without an impedance-reducing cover, the damage issue was solved by installing a distributed absorber in the most downstream ID. Themore » steering issues were mostly resolved by the introduction of appropriate corrector magnets and feedback. The paper is written from the viewpoint of an interested beamline scientist impressed with the cooperation of different groups to make a source for new science possible.« less

  20. PF-AR NW14, a new time-resolved diffraction/scattering beamline

    NASA Astrophysics Data System (ADS)

    Nozawa, Shunsuke; Adachi, Shin-ichi; Tazaki, Ryoko; Takahashi, Jun-ichi; Itatani, Jiro; Daimon, Masahiro; Mori, Takeharu; Sawa, Hiroshi; Kawata, Hiroshi; Koshihara, Shin-ya

    2005-01-01

    NW14 is a new insertion device beamline at the Photon Factory Advanced Ring (PF-AR), which is a unique ring with full-time single-bunched operation, aiming for timeresolved x-ray diffraction/scattering and XAFS experiments. The primary scientific goal of this beamline is to observe the ultrafast dynamics of condensed matter systems such as organic and inorganic crystals, biological systems and liquids triggered by optical pulses. With the large photon fluxes derived from the undulator, it should become possible to take a snapshoot an atomic-scale image of the electron density distribution. By combining a series of images it is possible to produce a movie of the photo-induced dynamics with 50-ps resolution. The construction of the beamline is being funded by the ERATO Koshihara Non-equilibrium Dynamics Project of the Japan Science and Technology Agency (JST), and the beamline will be operational from autumn 2005.

  1. Effectiveness of the Civil Aviation Security Program.

    DTIC Science & Technology

    1982-10-26

    12 IX. CIVIL AVIATION SECURITY ACTIONS . . . . . . 14 X . MPIANCE M EN4FOW . ........ 20 X . U . . . . . ... . . . . .. . . . 21 EXHIBITS 1...Screening Results 10. Weapon Detection Devices 11. X -Ray Baggage Inspection Systems 12. Basic Policies 13. Regulatory Impact 14. FAA Sponsored Explosive...WERE APPROVED FOR MORE THAN 200 AIRPORTS. D . TESTING WAS BEGUN ON A NEW C MPUTER PROGRAM FOR HE X -RAY ABSORPTION SYSTEM DEVELOPED TO DTECT BMBS IN

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chang, Seo Hyoung; Kim, Jungho; Phatak, Charudatta

    The interaction between X-rays and matter is an intriguing topic for both fundamental science and possible applications. In particular, synchrotron-based brilliant X-ray beams have been used as a powerful diagnostic tool to unveil nanoscale phenomena in functional materials. But, it has not been widely investigated how functional materials respond to the brilliant X-rays. Here, we report the X-ray-induced reversible resistance change in 40-nm-thick TiO 2 films sandwiched by Pt top and bottom electrodes, and propose the physical mechanism behind the emergent phenomenon. Our findings indicate that there exists a photovoltaic-like effect, which modulates the resistance reversibly by a few ordersmore » of magnitude, depending on the intensity of impinging X-rays. Furthermore, we found that this effect, combined with the X-ray irradiation induced phase transition confirmed by transmission electron microscopy, triggers a nonvolatile reversible resistance change. In understanding X-ray-controlled reversible resistance changes we can provide possibilities to control initial resistance states of functional materials, which could be useful for future information and energy storage devices.« less

  3. The Extended Range X-Ray Telescope center director's discretionary fund report

    NASA Technical Reports Server (NTRS)

    Hoover, R. B.; Cumings, N. P.; Hildner, E.; Moore, R. L.; Tandberg-Hanssen, E. A.

    1985-01-01

    An Extended Range X-Ray Telescope (ERXRT) of high sensitivity and spatial resolution capable of functioning over a broad region of the X-ray/XUV portion of the spectrum has been designed and analyzed. This system has been configured around the glancing-incidence Wolter Type I X-ray mirror system which was flown on the Skylab Apollo Telescope Mount as ATM Experiment S-056. Enhanced sensitivity over a vastly broader spectral range can be realized by the utilization of a thinned, back-illuminated, buried-channel Charge Coupled Device (CCD) as the X-ray/XUV detector rather than photographic film. However, to maintain the high spatial resolution inherent in the X-ray optics when a CCD of 30 micron pixel size is used, it is necessary to increase the telescope plate scale. This can be accomplished by use of a glancing-incidence X-ray microscope to enlarge and re-focus the primary image onto the focal surface of the CCD.

  4. Compton backscattered collimated x-ray source

    DOEpatents

    Ruth, R.D.; Huang, Z.

    1998-10-20

    A high-intensity, inexpensive and collimated x-ray source is disclosed for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications. 4 figs.

  5. Compton backscattered collimated x-ray source

    DOEpatents

    Ruth, Ronald D.; Huang, Zhirong

    1998-01-01

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  6. Compton backscattered collmated X-ray source

    DOEpatents

    Ruth, Ronald D.; Huang, Zhirong

    2000-01-01

    A high-intensity, inexpensive and collimated x-ray source for applications such as x-ray lithography is disclosed. An intense pulse from a high power laser, stored in a high-finesse resonator, repetitively collides nearly head-on with and Compton backscatters off a bunched electron beam, having relatively low energy and circulating in a compact storage ring. Both the laser and the electron beams are tightly focused and matched at the interaction region inside the optical resonator. The laser-electron interaction not only gives rise to x-rays at the desired wavelength, but also cools and stabilizes the electrons against intrabeam scattering and Coulomb repulsion with each other in the storage ring. This cooling provides a compact, intense bunch of electrons suitable for many applications. In particular, a sufficient amount of x-rays can be generated by this device to make it an excellent and flexible Compton backscattered x-ray (CBX) source for high throughput x-ray lithography and many other applications.

  7. Instrumentation for in situ flow electrochemical Scanning Transmission X-ray Microscopy (STXM)

    NASA Astrophysics Data System (ADS)

    Prabu, Vinod; Obst, Martin; Hosseinkhannazer, Hooman; Reynolds, Matthew; Rosendahl, Scott; Wang, Jian; Hitchcock, Adam P.

    2018-06-01

    We report the design and performance of a 3-electrode device for real time in situ scanning transmission X-ray microscopy studies of electrochemical processes under both static (sealed, non-flow) conditions and with a continuous flow of electrolytes. The device was made using a combination of silicon microfabrication and 3D printing technologies. The performance is illustrated by results of a study of copper deposition and stripping at a gold working electrode. X-ray absorption spectromicroscopy at the Cu 2p edge was used to follow the evolution as a function of potential and time of the spatial distributions of Cu(0) and Cu(i) species electro-deposited from an aqueous solution of copper sulphate. The results are interpreted in terms of competing mechanisms for the reduction of Cu(ii).

  8. Probing molecular orientations in thin films by x-ray photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Y.; Li, P.; Lu, Z.-H.

    2018-03-01

    A great number of functional organic molecules in active thin-film layers of optoelectronic devices have highly asymmetric structures, such as plate-like, rod-like, etc. This makes molecular orientation an important aspect in thin-films as it can significantly affect both the optical and electrical performance of optoelectronic devices. With a combination of in-situ ultra violet photoelectron spectroscopy (UPS) and x-ray photoelectron spectroscopy (XPS) investigations for organic molecules having a broad range of structural properties, we discovered a rigid connection of core levels and frontier highest occupied molecular orbital levels at organic interfaces. This finding opens up opportunities of using X-ray photoemission spectroscopy as an alternative tool to UPS for providing an easy and unambiguous data interpretation in probing molecular orientations.

  9. Two mirror X-ray pulse split and delay instrument for femtosecond time resolved investigations at the LCLS free electron laser facility

    DOE PAGES

    Berrah, Nora; Fang, Li; Murphy, Brendan F.; ...

    2016-05-20

    We built a two-mirror based X-ray split and delay (XRSD) device for soft X-rays at the Linac Coherent Light Source free electron laser facility. The instrument is based on an edge-polished mirror design covering an energy range of 250 eV-1800 eV and producing a delay between the two split pulses variable up to 400 femtoseconds with a sub-100 attosecond resolution. We present experimental and simulation results regarding molecular dissociation dynamics in CH3I and CO probed by the XRSD device. In conclusion, we observed ion kinetic energy and branching ratio dependence on the delay times which were reliably produced by themore » XRSD instrument.« less

  10. A study of mercuric iodide near melting using differential scanning calorimetry, Raman spectroscopy and X-ray diffraction

    NASA Astrophysics Data System (ADS)

    Burger, A.; Morgan, S.; Jiang, H.; Silberman, E.; Schieber, M.; Van Den Berg, L.; Keller, L.; Wagner, C. N. J.

    1989-11-01

    High-temperature studies of mercuric iodide (HgI2) involving differential scanning calorimetry (DSC), Raman spectroscopy and X-ray powder diffraction have failed to confirm the existence of a red-colored tetragonal high-temperature phase called α'-HgI2 reported by S.N. Toubektsis et al. [J. Appl. Phys. 58 (1988) 2070] using DSC measurements. The multiple DSC peaks near melting reported by Toubektsis are found by the present authors only if the sample is heated in a stainless-steel container. Using a Pyrex container or inserting a platinum foil between the HgI2 and the stainless-steel container yields only one sharp, single DSC peak at the melting point. The nonexistence of the α' phase is confirmed by high-temperature X-ray diffraction and Raman spectroscopy performed in the vicinity of the melting point. These methods clearly, indicate the existence of only the yellow orthorhombic β-HgI2 phase. The experimental high-temperature DSC, Raman and X-ray diffraction data are presented and discussed.

  11. X-ray Irradiation Induced Reversible Resistance Change in Pt/TiO 2 /Pt Cells

    DOE PAGES

    Chang, Seo Hyoung; Kim, Jungho; Phatak, Charudatta; ...

    2014-02-25

    The interaction between X-rays and matter is an intriguing topic for both fundamental science and possible applications. In particular, synchrotron-based brilliant X-ray beams have been used as a powerful diagnostic tool to unveil nanoscale phenomena in functional materials. But, it has not been widely investigated how functional materials respond to the brilliant X-rays. Here, we report the X-ray-induced reversible resistance change in 40-nm-thick TiO 2 films sandwiched by Pt top and bottom electrodes, and propose the physical mechanism behind the emergent phenomenon. Our findings indicate that there exists a photovoltaic-like effect, which modulates the resistance reversibly by a few ordersmore » of magnitude, depending on the intensity of impinging X-rays. Furthermore, we found that this effect, combined with the X-ray irradiation induced phase transition confirmed by transmission electron microscopy, triggers a nonvolatile reversible resistance change. In understanding X-ray-controlled reversible resistance changes we can provide possibilities to control initial resistance states of functional materials, which could be useful for future information and energy storage devices.« less

  12. Real-time X-ray Diffraction: Applications to Materials Characterization

    NASA Technical Reports Server (NTRS)

    Rosemeier, R. G.

    1984-01-01

    With the high speed growth of materials it becomes necessary to develop measuring systems which also have the capabilities of characterizing these materials at high speeds. One of the conventional techniques of characterizing materials was X-ray diffraction. Film, which is the oldest method of recording the X-ray diffraction phenomenon, is not quite adequate in most circumstances to record fast changing events. Even though conventional proportional counters and scintillation counters can provide the speed necessary to record these changing events, they lack the ability to provide image information which may be important in some types of experiment or production arrangements. A selected number of novel applications of using X-ray diffraction to characterize materials in real-time are discussed. Also, device characteristics of some X-ray intensifiers useful in instantaneous X-ray diffraction applications briefly presented. Real-time X-ray diffraction experiments with the incorporation of image X-ray intensification add a new dimension in the characterization of materials. The uses of real-time image intensification in laboratory and production arrangements are quite unlimited and their application depends more upon the ingenuity of the scientist or engineer.

  13. X-ray irradiation induced reversible resistance change in Pt/TiO2/Pt cells.

    PubMed

    Chang, Seo Hyoung; Kim, Jungho; Phatak, Charudatta; D'Aquila, Kenneth; Kim, Seong Keun; Kim, Jiyoon; Song, Seul Ji; Hwang, Cheol Seong; Eastman, Jeffrey A; Freeland, John W; Hong, Seungbum

    2014-02-25

    The interaction between X-rays and matter is an intriguing topic for both fundamental science and possible applications. In particular, synchrotron-based brilliant X-ray beams have been used as a powerful diagnostic tool to unveil nanoscale phenomena in functional materials. However, it has not been widely investigated how functional materials respond to the brilliant X-rays. Here, we report the X-ray-induced reversible resistance change in 40-nm-thick TiO2 films sandwiched by Pt top and bottom electrodes, and propose the physical mechanism behind the emergent phenomenon. Our findings indicate that there exists a photovoltaic-like effect, which modulates the resistance reversibly by a few orders of magnitude, depending on the intensity of impinging X-rays. We found that this effect, combined with the X-ray irradiation induced phase transition confirmed by transmission electron microscopy, triggers a nonvolatile reversible resistance change. Understanding X-ray-controlled reversible resistance changes can provide possibilities to control initial resistance states of functional materials, which could be useful for future information and energy storage devices.

  14. [Intraoperative augmented reality visualization. Current state of development and initial experiences with the CamC].

    PubMed

    Weidert, S; Wang, L; von der Heide, A; Navab, N; Euler, E

    2012-03-01

    The intraoperative application of augmented reality (AR) has so far mainly taken place in the field of endoscopy. Here, the camera image of the endoscope was augmented by computer graphics derived mostly from preoperative imaging. Due to the complex setup and operation of the devices, they have not yet become part of routine clinical practice. The Camera Augmented Mobile C-arm (CamC) that extends a classic C-arm by a video camera and mirror construction is characterized by its uncomplicated handling. It combines its video live stream geometrically correct with the acquired X-ray. The clinical application of the device in 43 cases showed the strengths of the device in positioning for X-ray acquisition, incision placement, K-wire placement, and instrument guidance. With its new function and the easy integration into the OR workflow of any procedure that requires X-ray imaging, the CamC has the potential to become the first widely used AR technology for orthopedic and trauma surgery.

  15. Comparative study of radiation emission without and with target in a 2.2 kJ plasma focus device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khan, Muhammad Zubair, E-mail: mzubairkhan-um76@yahoo.com; Ling, Yap Seong; San, Wong Chiow

    The radiation emission in a 2.2 kJ Mather-type dense plasma focus device is investigated using a five channel BPX65 PIN diode spectrometer. Estimated X-ray associated with the hollow anode without and with target in Argon gas medium is compared. At optimum conditions, the radiation emission from the system is found to be strongly influenced with target in hollow anode and the filling gas pressure. The maximum X-ray yield in 4π sr was obtained in case of hollow anode in argon gas medium with target 'Lead' due to interaction of electron beam. Results indicated that an appropriate design of hollow anodemore » with target could enhance the radiation emission by more intense interaction of expected electron beam with target. The outcomes are helpful in designing a plasma focus with enhanced X-ray radiation with improved shot to shot reproducibility in plasma focus device.« less

  16. Uncooled spectrometer for x-ray astrophysics

    NASA Astrophysics Data System (ADS)

    Urban, Martin; Nentvich, Ondrej; Stehlikova, Veronika; Sieger, Ladislav

    2017-05-01

    In the field of X-ray detection for Astrophysics there are mainly two objectives; first is to create 2D images as a result of sensing radiation by detectors consisting of a pixels matrix and the second is a spectral analysis of the incident radiation. For spectral analysis, the basis is usually the principle of diffraction. This paper describes the new design of X-ray spectrometer based on Timepix detector with optics positioned in front of it. The advantage of this setup is the ability to get the image and spectrum from the same devices. With other modifications is possible to shift detection threshold into areas of soft X-ray radiation.

  17. Pulsed x-ray sources for characterization of gated framing cameras

    NASA Astrophysics Data System (ADS)

    Filip, Catalin V.; Koch, Jeffrey A.; Freeman, Richard R.; King, James A.

    2017-08-01

    Gated X-ray framing cameras are used to measure important characteristics of inertial confinement fusion (ICF) implosions such as size and symmetry, with 50 ps time resolution in two dimensions. A pulsed source of hard (>8 keV) X-rays, would be a valuable calibration device, for example for gain-droop measurements of the variation in sensitivity of the gated strips. We have explored the requirements for such a source and a variety of options that could meet these requirements. We find that a small-size dense plasma focus machine could be a practical single-shot X-ray source for this application if timing uncertainties can be overcome.

  18. Beam Conditioning and Harmonic Generation in Free ElectronLasers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Charman, A.E.; Penn, G.; Wolski, A.

    2004-07-05

    The next generation of large-scale free-electron lasers (FELs) such as Euro-XFEL and LCLS are to be devices which produce coherent X-rays using Self-Amplified Spontaneous Emission (SASE). The performance of these devices is limited by the spread in longitudinal velocities of the beam. In the case where this spread arises primarily from large transverse oscillation amplitudes, beam conditioning can significantly enhance FEL performance. Future X-ray sources may also exploit harmonic generation starting from laser-seeded modulation. Preliminary analysis of such devices is discussed, based on a novel trial-function/variational-principle approach, which shows good agreement with more lengthy numerical simulations.

  19. Bilateral Pneumothoraces in a Trauma Patient After Dobhoff Tube Insertion.

    PubMed

    Abidali, Ali; Mangram, Alicia; Shirah, Gina R; Wilson, Whitney; Abidali, Ahmed; Moeser, Phillip; Dzandu, James K

    2018-03-05

    BACKGROUND Dobhoff tube insertion is a common procedure used in the clinical setting to deliver enteral nutrition. Although it is often viewed as an innocuous bedside procedure, there are risks for numerous complications such as tracheobronchial insertion, which could lead to deleterious consequences. We present to our knowledge the first reported case of bilateral pneumothoraces caused by the insertion of a Dobhoff tube. In addition, we also discuss common pitfalls for confirming the positioning of Dobhoff tubes, as well as risk factors that can predispose a patient to improper tube placement. CASE REPORT We present the case of a 74-year-old male patient with multiple orthopedic injuries following an auto-pedestrian collision. Five attempts were made to place a Dobhoff tube to maintain enteral nutrition. Follow-up abdominal x-ray revealed displacement of the Dobhoff tube in the left pleural space. After removal of the tube, a follow-up chest x-ray revealed iatrogenic bilateral pneumothoraces. Acute hypoxemic respiratory failure ensued; therefore, bilateral chest tubes were placed. Over the next three weeks, the patient's respiratory status improved and both chest tubes were removed. The patient was eventually discharged to a skilled nursing facility. CONCLUSIONS Improper placement of Dobhoff tubes can lead to rare complications such as bilateral pneumothoraces. This unique case report of bilateral pneumothoraces after Dobhoff tube placement emphasizes the necessity of using proper diagnostic techniques for verifying proper tube placement, as well as understanding the risk factors that predispose a patient to a malpositioned tube.

  20. 21 CFR 892.1600 - Angiographic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Angiographic x-ray system. 892.1600 Section 892.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... device may include signal analysis and display equipment, patient and equipment supports, component parts...

  1. 21 CFR 892.1600 - Angiographic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Angiographic x-ray system. 892.1600 Section 892.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... device may include signal analysis and display equipment, patient and equipment supports, component parts...

  2. 21 CFR 892.1710 - Mammographic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Mammographic x-ray system. 892.1710 Section 892.1710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  3. 21 CFR 892.1720 - Mobile x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Mobile x-ray system. 892.1720 Section 892.1720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... for diagnostic procedures. This generic type of device may include signal analysis and display...

  4. 21 CFR 892.1720 - Mobile x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Mobile x-ray system. 892.1720 Section 892.1720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... for diagnostic procedures. This generic type of device may include signal analysis and display...

  5. 21 CFR 892.1740 - Tomographic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Tomographic x-ray system. 892.1740 Section 892.1740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  6. 21 CFR 892.1730 - Photofluorographic x-ray system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Photofluorographic x-ray system. 892.1730 Section 892.1730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  7. 21 CFR 892.1740 - Tomographic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tomographic x-ray system. 892.1740 Section 892.1740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  8. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... through electronic amplification. This generic type of device may include signal analysis and display...

  9. 21 CFR 892.1710 - Mammographic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Mammographic x-ray system. 892.1710 Section 892.1710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  10. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... through electronic amplification. This generic type of device may include signal analysis and display...

  11. 21 CFR 892.1740 - Tomographic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Tomographic x-ray system. 892.1740 Section 892.1740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  12. 21 CFR 892.1730 - Photofluorographic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Photofluorographic x-ray system. 892.1730 Section 892.1730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  13. 21 CFR 892.1720 - Mobile x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Mobile x-ray system. 892.1720 Section 892.1720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... for diagnostic procedures. This generic type of device may include signal analysis and display...

  14. 21 CFR 892.1730 - Photofluorographic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Photofluorographic x-ray system. 892.1730 Section 892.1730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  15. 21 CFR 892.1710 - Mammographic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mammographic x-ray system. 892.1710 Section 892.1710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  16. 21 CFR 892.1740 - Tomographic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Tomographic x-ray system. 892.1740 Section 892.1740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  17. 21 CFR 892.1710 - Mammographic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Mammographic x-ray system. 892.1710 Section 892.1710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  18. 21 CFR 892.1600 - Angiographic x-ray system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Angiographic x-ray system. 892.1600 Section 892.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... device may include signal analysis and display equipment, patient and equipment supports, component parts...

  19. 21 CFR 892.1740 - Tomographic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Tomographic x-ray system. 892.1740 Section 892.1740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  20. 21 CFR 892.1730 - Photofluorographic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Photofluorographic x-ray system. 892.1730 Section 892.1730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  1. 21 CFR 892.1720 - Mobile x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Mobile x-ray system. 892.1720 Section 892.1720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... for diagnostic procedures. This generic type of device may include signal analysis and display...

  2. 21 CFR 892.1650 - Image-intensified fluoroscopic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Image-intensified fluoroscopic x-ray system. 892.1650 Section 892.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... through electronic amplification. This generic type of device may include signal analysis and display...

  3. 21 CFR 892.1600 - Angiographic x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Angiographic x-ray system. 892.1600 Section 892.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... device may include signal analysis and display equipment, patient and equipment supports, component parts...

  4. 21 CFR 892.1720 - Mobile x-ray system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mobile x-ray system. 892.1720 Section 892.1720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... for diagnostic procedures. This generic type of device may include signal analysis and display...

  5. 21 CFR 892.1710 - Mammographic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Mammographic x-ray system. 892.1710 Section 892.1710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  6. 21 CFR 892.1600 - Angiographic x-ray system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Angiographic x-ray system. 892.1600 Section 892.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... device may include signal analysis and display equipment, patient and equipment supports, component parts...

  7. 21 CFR 892.1730 - Photofluorographic x-ray system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Photofluorographic x-ray system. 892.1730 Section 892.1730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES.... This generic type of device may include signal analysis and display equipment, patient and equipment...

  8. The detection of soft X-rays with charged coupled detectors

    NASA Technical Reports Server (NTRS)

    Burstein, P.; Davis, John M.

    1989-01-01

    The characteristics of an ideal soft X-ray imaging detector are enumerated. Of recent technical developments the CCD or charge coupled device goes furthest to meeting these requirements. Several properties of CCDs are described with reference to experimental work and their application to practical instruments is reviewed.

  9. A high-voltage rechargeable magnesium-sodium hybrid battery

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Yifei; An, Qinyou; Cheng, Yingwen

    2017-04-01

    Growing global demand of safe and low-cost energy storage technology triggers strong interests in novel battery concepts beyond state-of-art Li-ion batteries. Here we report a high-voltage rechargeable Mg–Na hybrid battery featuring dendrite-free deposition of Mg anode and Na-intercalation cathode as a low-cost and safe alternative to Li-ion batteries for large-scale energy storage. A prototype device using a Na3V2(PO4)3 cathode, a Mg anode, and a Mg–Na dual salt electrolyte exhibits the highest voltage (2.60 V vs. Mg) and best rate performance (86% capacity retention at 10C rate) among reported hybrid batteries. Synchrotron radiation-based X-ray absorption near edge structure (XANES), atomic-pair distributionmore » function (PDF), and high-resolution X-ray diffraction (HRXRD) studies reveal the chemical environment and structural change of Na3V2(PO4)3 cathode during the Na ion insertion/deinsertion process. XANES study shows a clear reversible shift of vanadium K-edge and HRXRD and PDF studies reveal a reversible two-phase transformation and V–O bond length change during cycling. The energy density of the hybrid cell could be further improved by developing electrolytes with a higher salt concentration and wider electrochemical window. This work represents a significant step forward for practical safe and low-cost hybrid batteries.« less

  10. A high-voltage rechargeable magnesium-sodium hybrid battery

    DOE PAGES

    Li, Yifei; An, Qinyou; Cheng, Yingwen; ...

    2017-02-13

    There is a growing global demand for safe and low-cost energy storage technology which triggers strong interests in novel battery concepts beyond state-of-art Li-ion batteries. We report a high-voltage rechargeable Mg–Na hybrid battery featuring dendrite-free deposition of Mg anode and Na-intercalation cathode as a low-cost and safe alternative to Li-ion batteries for large-scale energy storage. A prototype device using a Na 3V 2(PO 4) 3 cathode, a Mg anode, and a Mg–Na dual salt electrolyte exhibits the highest voltage (2.60 V vs. Mg) and best rate performance (86% capacity retention at 10 C rate) among reported hybrid batteries. Synchrotron radiation-basedmore » X-ray absorption near edge structure (XANES), atomic-pair distribution function (PDF), and high-resolution X-ray diffraction (HRXRD) studies reveal the chemical environment and structural change of Na 3V 2(PO 4) 3 cathode during the Na ion insertion/deinsertion process. XANES study shows a clear reversible shift of vanadium K-edge and HRXRD and PDF studies reveal a reversible two-phase transformation and V–O bond length change during cycling. The energy density of the hybrid cell could be further improved by developing electrolytes with a higher salt concentration and wider electrochemical window. Our work represents a significant step forward for practical safe and low-cost hybrid batteries.« less

  11. Effects of interfaces on the thermal conductivity in Si/Si0.75Ge0.25 multilayer with varying Au layers

    NASA Astrophysics Data System (ADS)

    Hu, Yangsen; Wu, Zhenghua; Ye, Fengjie; Hu, Zhiyu

    2018-02-01

    The manoeuvre of thermal transport property across multilayer films with inserted metal layers through controlling the metal-nonmetal interfaces is of fundamental interest. In this work, amorphous Si/Si0.75Ge0.25 multilayer films inserted with varying Au layers were fabricated by magnetron sputtering. The structure and sharp interface of multilayers films were characterized by low angle x-ray diffraction (LAXRD), grazing incidence small angle x-ray scattering (GISAXS) and scanning electron microscopy (SEM). A differential 3ω method was applied to measure the effective thermal conductivity. The measurements show that thermal conductivity has changed as varying Au layers. Thermal conductivity increased from 0.94 to 1.31 Wm-1K-1 while Si0.75Ge0.25 layer was replaced by different Au layers, which was attributed to the strong electron-phonon coupling and interface thermal resistance in a metal-nonmetal multilayered system. Theoretical calculation combined with experimental results indicate that the thermal conductivity of the multilayer film could be facilely controlled by introducing different number of nanoconstructed metal-nonmetal interfaces, which provide a more insightful understanding of the thermal transport manipulation mechanism of the thin film system with inserting metal layers.

  12. X-ray luminescence computed tomography using a focused x-ray beam.

    PubMed

    Zhang, Wei; Lun, Michael C; Nguyen, Alex Anh-Tu; Li, Changqing

    2017-11-01

    Due to the low x-ray photon utilization efficiency and low measurement sensitivity of the electron multiplying charge coupled device camera setup, the collimator-based narrow beam x-ray luminescence computed tomography (XLCT) usually requires a long measurement time. We, for the first time, report a focused x-ray beam-based XLCT imaging system with measurements by a single optical fiber bundle and a photomultiplier tube (PMT). An x-ray tube with a polycapillary lens was used to generate a focused x-ray beam whose x-ray photon density is 1200 times larger than a collimated x-ray beam. An optical fiber bundle was employed to collect and deliver the emitted photons on the phantom surface to the PMT. The total measurement time was reduced to 12.5 min. For numerical simulations of both single and six fiber bundle cases, we were able to reconstruct six targets successfully. For the phantom experiment, two targets with an edge-to-edge distance of 0.4 mm and a center-to-center distance of 0.8 mm were successfully reconstructed by the measurement setup with a single fiber bundle and a PMT. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  13. Fast scattering simulation tool for multi-energy x-ray imaging

    NASA Astrophysics Data System (ADS)

    Sossin, A.; Tabary, J.; Rebuffel, V.; Létang, J. M.; Freud, N.; Verger, L.

    2015-12-01

    A combination of Monte Carlo (MC) and deterministic approaches was employed as a means of creating a simulation tool capable of providing energy resolved x-ray primary and scatter images within a reasonable time interval. Libraries of Sindbad, a previously developed x-ray simulation software, were used in the development. The scatter simulation capabilities of the tool were validated through simulation with the aid of GATE and through experimentation by using a spectrometric CdTe detector. A simple cylindrical phantom with cavities and an aluminum insert was used. Cross-validation with GATE showed good agreement with a global spatial error of 1.5% and a maximum scatter spectrum error of around 6%. Experimental validation also supported the accuracy of the simulations obtained from the developed software with a global spatial error of 1.8% and a maximum error of around 8.5% in the scatter spectra.

  14. Penetration of HIV-1 Tat47-57 into PC/PE Bilayers Assessed by MD Simulation and X-ray Scattering.

    PubMed

    Neale, Chris; Huang, Kun; García, Angel E; Tristram-Nagle, Stephanie

    2015-09-22

    The interactions of the basic, cell-penetrating region (Y47GRKKRRQRRR57) of the HIV-1 Tat protein with dioleoylphosphatidylcholine (DOPC) bilayers were previously assessed by comparing experimental X-ray diffuse scattering with atomistic molecular dynamics simulations. Here, we extend this investigation by evaluating the influence of phosphatidylethanolamine (PE) lipids. Using experimental bilayer form factors derivedfrom X-ray diffuse scattering data as a guide, our simulations indicate that Tat peptides localize close to the carbonyl-glycerol group in the headgroup region of bilayers composed of either DOPC or DOPC:DOPE (1:1) lipid. Our results also suggest that Tat peptides may more frequently insert into the hydrophobic core of bilayers composed of PC:PE (1:1) lipids than into bilayers composed entirely of PC lipids. PE lipids may facilitate peptide translocation across a lipid bilayer by stabilizing intermediate states in which hydrated peptides span the bilayer.

  15. Structural-electrochemical relations in the aqueous copper hexacyanoferrate-zinc system examined by synchrotron X-ray diffraction

    NASA Astrophysics Data System (ADS)

    Renman, Viktor; Ojwang, Dickson O.; Valvo, Mario; Gómez, Cesar Pay; Gustafsson, Torbjörn; Svensson, Gunnar

    2017-11-01

    The storage process of Zn2+ in the Prussian blue analogue (PBA) copper hexacyanoferrate (Cu[Fe(CN)6]2/3·nH2O - CuHCF) framework structure in a context of rechargeable aqueous batteries is examined by means of in operando synchrotron X-ray diffraction. Via sequential unit-cell parameter refinements of time-resolved diffraction data, it is revealed that the step-profile of the cell output voltage curves during repeated electrochemical insertion and removal of Zn2+ in the CuHCF host structure is associated with a non-linear contraction and expansion of the unit-cell in the range 0.36 < x < 1.32 for Znx/3Cu[Fe(CN)6]2/3·nH2O. For a high insertion cation content there is no apparent change in the unit-cell contraction. Furthermore, a structural analysis with respect to the occupancies of possible Zn2+ sites suggests that the Fe(CN)6 vacancies within the CuHCF framework play an important role in the structural-electrochemical behavior of this particular system. More specifically, it is observed that Zn2+ swaps position during electrochemical cycling, hopping between cavity sites to vacant ferricyanide sites.

  16. Relativistic klystron driven compact high gradient accelerator as an injector to an X-ray synchrotron radiation ring

    DOEpatents

    Yu, David U. L.

    1990-01-01

    A compact high gradient accelerator driven by a relativistic klystron is utilized to inject high energy electrons into an X-ray synchrotron radiation ring. The high gradients provided by the relativistic klystron enables accelerator structure to be much shorter (typically 3 meters) than conventional injectors. This in turn enables manufacturers which utilize high energy, high intensity X-rays to produce various devices, such as computer chips, to do so on a cost effective basis.

  17. Research study on stellar X-ray imaging experiment, volume 1

    NASA Technical Reports Server (NTRS)

    Wilson, H. H.; Vanspeybroeck, L. P.

    1972-01-01

    The use of microchannel plates as focal plane readout devices and the evaluation of mirrors for X-ray telescopes applied to stellar X-ray imaging is discussed. The microchannel plate outputs were either imaged on a phosphor screen which was viewed by a low light level vidicon or on a wire array which was read out by digitally processing the output of a charge division network attached to the wires. A service life test which was conducted on two image intensifiers is described.

  18. Descemet's Stripping Automated Endothelial Keratoplasty Tissue Insertion Devices

    PubMed Central

    Khan, Salman Nasir; Shiakolas, Panos S.; Mootha, Venkateswara Vinod

    2015-01-01

    This review study provides information regarding the construction, design, and use of six commercially available endothelial allograft insertion devices applied for Descemet's stripping automated endothelial keratoplasty (DSAEK). We also highlight issues being faced in DSAEK and discuss the methods through which medical devices such as corneal inserters may alleviate these issues. Inserter selection is of high importance in the DSAEK procedure since overcoming the learning curve associated with the use of an insertion device is a time and energy consuming process. In the present review, allograft insertion devices were compared in terms of design, construction material, insertion technique, dimensions, incision requirements and endothelial cell loss to show their relative merits and capabilities based on available data in the literature. Moreover, the advantages/disadvantages of various insertion devices used for allograft insertion in DSAEK are reviewed and compared. The information presented in this review can be utilized for better selection of an insertion device for DSAEK. PMID:27051492

  19. Report on New Mission Concept Study: Stereo X-Ray Corona Imager Mission

    NASA Technical Reports Server (NTRS)

    Liewer, Paulett C.; Davis, John M.; DeJong, E. M.; Gary, G. Allen; Klimchuk, James A.; Reinert, R. P.

    1998-01-01

    Studies of the three-dimensional structure and dynamics of the solar corona have been severely limited by the constraint of single viewpoint observations. The Stereo X-Ray Coronal Imager (SXCI) mission will send a single instrument, an X-ray telescope, into deep space expressly to record stereoscopic images of the solar corona. The SXCI spacecraft will be inserted into a approximately 1 AU heliocentric orbit leading Earth by approximately 25 deg at the end of nine months. The SXCI X-ray telescope forms one element of a stereo pair, the second element being an identical X-ray telescope in Earth orbit placed there as part of the NOAA GOES program. X-ray emission is a powerful diagnostic of the corona and its magnetic fields, and three dimensional information on the coronal magnetic structure would be obtained by combining the data from the two X-ray telescopes. This information can be used to address the major solar physics questions of (1) what causes explosive coronal events such as coronal mass ejections (CMEs), eruptive flares and prominence eruptions and (2) what causes the transient heating of coronal loops. Stereoscopic views of the optically thin corona will resolve some ambiguities inherent in single line-of-sight observations. Triangulation gives 3D solar coordinates of features which can be seen in the simultaneous images from both telescopes. As part of this study, tools were developed for determining the 3D geometry of coronal features using triangulation. Advanced technologies for visualization and analysis of stereo images were tested. Results of mission and spacecraft studies are also reported.

  20. Phantom evaluation of a cardiac SPECT/VCT system that uses a common set of solid-state detectors for both emission and transmission scans

    PubMed Central

    Conwell, Richard; Kindem, Joel; Babla, Hetal; Gurley, Mike; De Los Santos, Romer; Old, Rex; Weatherhead, Randy; Arram, Samia; Maddahi, Jamshid

    2010-01-01

    Background We developed a cardiac SPECT system (X-ACT) with low dose volume CT transmission-based attenuation correction (AC). Three solid-state detectors are configured to form a triple-head system for emission scans and reconfigured to form a 69-cm field-of-view detector arc for transmission scans. A near mono-energetic transmission line source is produced from the collimated fluorescence x-ray emitted from a lead target when the target is illuminated by a narrow polychromatic x-ray beam from an x-ray tube. Transmission scans can be completed in 1 min with insignificant patient dose (deep dose equivalent <5 μSv). Methods We used phantom studies to evaluate (1) the accuracy of the reconstructed attenuation maps, (2) the effect of AC on image uniformity, and (3) the effect of AC on defect contrast (DC). The phantoms we used included an ACR phantom, an anthropomorphic phantom with a uniform cardiac insert, and an anthropomorphic phantom with two defects in the cardiac insert. Results The reconstructed attenuation coefficient of water at 140 keV was .150 ± .003/cm in the uniform region of the ACR phantom, .151 ± .003/cm and .151 ± .002/cm in the liver and cardiac regions of the anthropomorphic phantom. The ACR phantom images with AC showed correction of the bowing effect due to attenuation in the images without AC (NC). The 17-segment scores of the images of the uniform cardiac insert were 78.3 ± 6.5 before and 87.9 ± 3.3 after AC (average ± standard deviation). The inferior-to-anterior wall ratio and the septal-to-lateral wall ratio were .99 and 1.16 before and 1.02 and 1.00 after AC. The DC of the two defects was .528 and .156 before and .628 and .173 after AC. Conclusion The X-ACT system generated accurate attenuation maps with 1-minute transmission scans. AC improved image quality and uniformity over NC. PMID:20169476

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