Automating X-ray Fluorescence Analysis for Rapid Astrobiology Surveys.

Science.gov (United States)

Thompson, David R; Flannery, David T; Lanka, Ravi; Allwood, Abigail C; Bue, Brian D; Clark, Benton C; Elam, W Timothy; Estlin, Tara A; Hodyss, Robert P; Hurowitz, Joel A; Liu, Yang; Wade, Lawrence A

2015-11-01

A new generation of planetary rover instruments, such as PIXL (Planetary Instrument for X-ray Lithochemistry) and SHERLOC (Scanning Habitable Environments with Raman Luminescence for Organics and Chemicals) selected for the Mars 2020 mission rover payload, aim to map mineralogical and elemental composition in situ at microscopic scales. These instruments will produce large spectral cubes with thousands of channels acquired over thousands of spatial locations, a large potential science yield limited mainly by the time required to acquire a measurement after placement. A secondary bottleneck also faces mission planners after downlink; analysts must interpret the complex data products quickly to inform tactical planning for the next command cycle. This study demonstrates operational approaches to overcome these bottlenecks by specialized early-stage science data processing. Onboard, simple real-time systems can perform a basic compositional assessment, recognizing specific features of interest and optimizing sensor integration time to characterize anomalies. On the ground, statistically motivated visualization can make raw uncalibrated data products more interpretable for tactical decision making. Techniques such as manifold dimensionality reduction can help operators comprehend large databases at a glance, identifying trends and anomalies in data. These onboard and ground-side analyses can complement a quantitative interpretation. We evaluate system performance for the case study of PIXL, an X-ray fluorescence spectrometer. Experiments on three representative samples demonstrate improved methods for onboard and ground-side automation and illustrate new astrobiological science capabilities unavailable in previous planetary instruments. Dimensionality reduction-Planetary science-Visualization.

ON THE USE OF DUAL-CO-POLARIZED TERRASAR-X DATA FOR WETLAND MONITORING

Directory of Open Access Journals (Sweden)

A. Schmitt

2012-08-01

Full Text Available Today's SAR sensors provide a variety of different image modes particularly with regard to multipolarised acquisitions. Until now, each polarisation mode requires a special decomposition which is a severe drawback when designing processing chains. Therefore, a new description for multipolarized SAR data based on the well-known Kennaugh matrix was developed that enables the uniform description and processing of SAR data independent of its polarisation by separating backscattering strength from polarimetric information. This mathematical approach subsequently is extended to the processing of multitemporal SAR data in order to stabilize the polarimetric information over longer periods of time and to enhance temporal changes in the polarimetric backscattering. Because of the high sensitivity of the Kennaugh elements a novel multilooking technique based on the Gaussian pyramid is used that locally adapts the look factor and thus selects the optimal balance between radiometric accuracy and geometric resolution. This methodology is applied to two dual-co-polarized TerraSAR-X acquisitions over the RAMSAR testsite "Upper Rhine" in order to generate value-added products that help to map land cover and land cover changes in consequence of water level changes. The first results are very promising although the interpretation of the observed polarimetric changes is not yet validated. The aim of this paper is to present a further application of the (Differential Kennaugh matrix which will be the kernel of a polarimetry and change detection processor to be implemented in the coming years.

Synchrotron X-ray fluorescence analysis in environmental and earth sciences

Directory of Open Access Journals (Sweden)

Adams F.

2010-12-01

Full Text Available Compared to other microscopic analytical tools X-ray microscopy techniques have the advantage that the large penetration depth of X-rays in matter allows one to investigate the interior of an object without destructive sample preparation. In combination with X-ray fluorescence tomography, analytical information from inside of a specimen can be obtained. Different X-ray analytical techniques can be used to produce contrast, X-ray absorption, fluorescence, and diffraction, to yield chemical, elemental, and structural information about the sample. Scanning microscopy on the basis of various lens systems in synchrotron radiation sources provides a routine spatial resolution of now about 100 nanometer but in the foreseeable future a 10–20 nanometer spatial resolution can be expected. X-ray absorption spectrometry can also provide chemical (speciation information on the sample. All this makes X-ray microscopy attractive to many fields of science. In this paper the techniques are briefly reviewed and a number of applications in the earth, planetary and cosmos sciences are illustrated with state-of-the art examples, while applications in the environmental sciences and biology are also briefly discussed.

Estimation of Atmospheric Path Delays in TerraSAR-X Data using Models vs. Measurements

Directory of Open Access Journals (Sweden)

Donat Perler

2008-12-01

Full Text Available Spaceborne synthetic aperture radar (SAR measurements of the Earth’s surface depend on electromagnetic waves that are subject to atmospheric path delays, in turn affecting geolocation accuracy. The atmosphere influences radar signal propagation by modifying its velocity and direction, effects which can be modeled. We use TerraSAR-X (TSX data to investigate improvements in the knowledge of the scene geometry. To precisely estimate atmospheric path delays, we analyse the signal return of four corner reflectors with accurately surveyed positions (based on differential GPS, placed at different altitudes yet with nearly identical slant ranges to the sensor. The comparison of multiple measurements with path delay models under these geometric conditions also makes it possible to evaluate the corrections for the atmospheric path delay made by the TerraSAR processor and to propose possible improvements.

Raios-x: fascinação, medo e ciência X-rays: fascination, fear and science

Directory of Open Access Journals (Sweden)

Rodrigo da Silva Lima

2009-01-01

Full Text Available This work presents the discovery and the use of x-rays at the end of the XIXth and the beginning of the XXth century. X-rays greatly impacted science and everyday life. Their existence broke the idea that knowledge had reached a limiting step. In general, people regarded x-rays as a marvel of science, but reactions against their use were also found. Several applications were proposed, especially in medicine. However, little or no attention was paid to security measures, leading to health damages and even death. The development of the radiological protection took into account the accidents with the x-rays.

Materials Science and X-ray Techniques

International Nuclear Information System (INIS)

Brock, J.; Sutton, M.

2008-01-01

Many novel synchrotron-based X-ray techniques directly address the core questions of modern materials science but are not yet at the stage of being easy to use because of the lack of dedicated beamlines optimized for specific measurements. In this article, we highlight a few of these X-ray techniques and discuss why, with ongoing upgrades of existing synchrotrons and with new linear-accelerator-based sources under development, now is the time to ensure that these techniques are readily available to the larger materials research community.

The Role of Project Science in the Chandra X-Ray Observatory

Science.gov (United States)

O'Dell, Stephen L.; Weisskopf, Martin C.

2006-01-01

The Chandra X-Ray Observatory, one of NASA's Great Observatories, has an outstanding record of scientific and technical success. This success results from the efforts of a team comprising NASA, its contractors, the Smithsonian Astrophysical Observatory, the instrument groups, and other elements of the scientific community, including thousands of scientists who utilize this powerful facility for astrophysical research. We discuss the role of NASA Project Science in the formulation, development, calibration, and operation of the Chandra X-ray Observatory. In addition to representing the scientific community within the Project, Project Science performed what we term "science systems engineering". This activity encompasses translation of science requirements into technical requirements and assessment of the scientific impact of programmatic and technical trades. We briefly describe several examples of science systems engineering conducted by Chandra Project Science.

Development of an x-ray beam line at the NSLS for studies in materials science using x-ray absorption spectroscopy: Annual progress report

International Nuclear Information System (INIS)

Sayers, D.E.

1987-01-01

The research programs reported span virtually the entire range of condensed matter studies involving the fields of solid state physics, chemistry, electrochemistry, materials science and biochemistry. Results are discussed for various groups. Topics reported include work on amorphous chalcogenide semiconductors, particularly photostructural changes, kinetics of structural changes and rapid quenching, bond strengths, force constants and phonons. Also reported are temperature dependent EXAFS studies of bonding in high temperature alloys, amorphous systems, disordered alloys and studies of resolve electronic structure, EXAFS and XANES studies of permanent magnet systems based on Nd 2 Fe 14 B, glancing angle EXAFS study of Nb/Al and Nb/Si interfacial systems, x-ray absorption of krypton-implanted solids and high dose implants into silicon, and x-ray absorption and EXAFS studies of superconducting oxide compounds of Cu and related magnetic systems. Work is also reported on XAFS measurements on the icosahedral phase

Time-resolved materials science opportunities using synchrotron x-ray sources

International Nuclear Information System (INIS)

Larson, B.C.; Tischler, J.Z.

1995-06-01

The high brightness, high intensity, and pulsed time-structure of synchrotron sources provide new opportunities for time-resolved x-ray diffraction investigations. With third generation synchrotron sources coming on line, high brilliance and high brightness are now available in x-ray beams with the highest flux. In addition to the high average flux, the instantaneous flux available in synchrotron beams is greatly enhanced by the pulsed time structure, which consists of short bursts of x-rays that are separated by ∼tens to hundreds of nanoseconds. Time-resolved one- and two-dimensional position sensitive detection techniques that take advantage of synchrotron radiation for materials science x-ray diffraction investigations are presented, and time resolved materials science applications are discussed in terms of recent diffraction and spectroscopy results and materials research opportunities

New Worlds / New Horizons Science with an X-ray Astrophysics Probe

Science.gov (United States)

Smith, Randall K.; Bookbinder, Jay A.; Hornschemeier, Ann E.; Bandler, Simon; Brandt, W. N.; Hughes, John P.; McCammon, Dan; Matsumoto, Hironori; Mushotzky, Richard; Osten, Rachel A.;

An X-ray outburst from the rapidly accreting young star that illuminates McNeil's nebula.

Science.gov (United States)

Kastner, J H; Richmond, M; Grosso, N; Weintraub, D A; Simon, T; Frank, A; Hamaguchi, K; Ozawa, H; Henden, A

2004-07-22

Young, low-mass stars are luminous X-ray sources whose powerful X-ray flares may exert a profound influence over the process of planet formation. The origin of the X-ray emission is uncertain. Although many (or perhaps most) recently formed, low-mass stars emit X-rays as a consequence of solar-like coronal activity, it has also been suggested that X-ray emission may be a direct result of mass accretion onto the forming star. Here we report X-ray imaging spectroscopy observations which reveal a factor approximately 50 increase in the X-ray flux from a young star that is at present undergoing a spectacular optical/infrared outburst (this star illuminates McNeil's nebula). The outburst seems to be due to the sudden onset of a phase of rapid accretion. The coincidence of a surge in X-ray brightness with the optical/infrared eruption demonstrates that strongly enhanced high-energy emission from young stars can occur as a consequence of high accretion rates. We suggest that such accretion-enhanced X-ray emission from erupting young stars may be short-lived, because intense star-disk magnetospheric interactions are quenched rapidly by the subsequent flood of new material onto the star.

Dark Energy, Dark Matter and Science with Constellation-X

Science.gov (United States)

Cardiff, Ann Hornschemeier

2005-01-01

Constellation-X, with more than 100 times the collecting area of any previous spectroscopic mission operating in the 0.25-40 keV bandpass, will enable highthroughput, high spectral resolution studies of sources ranging from the most luminous accreting supermassive black holes in the Universe to the disks around young stars where planets form. This talk will review the updated Constellation-X science case, released in booklet form during summer 2005. The science areas where Constellation-X will have major impact include the exploration of the space-time geometry of black holes spanning nine orders of magnitude in mass and the nature of the dark energy and dark matter which govern the expansion and ultimate fate of the Universe. Constellation-X will also explore processes referred to as "cosmic feedback" whereby mechanical energy, radiation, and chemical elements from star formation and black holes are returned to interstellar and intergalactic medium, profoundly affecting the development of structure in the Universe, and will also probe all the important life cycles of matter, from stellar and planetary birth to stellar death via supernova to stellar endpoints in the form of accreting binaries and supernova remnants. This talk will touch upon all these areas, with particular emphasis on Constellation-X's role in the study of Dark Energy.

Rapid extraction and x-ray fluorescence determination of gold in rock

International Nuclear Information System (INIS)

Lobanov, F.I.; Logunova, S.A.; Popov, A.M.; Krasnopevtseva, E.V.

1994-01-01

The optimal conditions for gold extractional recovery by melts of aliphatic monocarboxylic acids mixtures (C ≥ 16) with additions of di-2-ethylhexyldithiophosphoric acid, di-n-oxtylsulfide and alkylaniline were determined. A rapid method of extraction and X-ray fluorescence detection of gold in the presence of considerable amounts of Fe, Cu, Pb, Cd, Zn and Bi was developed

Characteristics of sets of diffusion photographic materials for rapid X-ray radiography

International Nuclear Information System (INIS)

Gusev, E.A.; Neduv, A.M.; Korolev, A.I.; Mirzoyan, I.N.; Chelnokov, V.B.

1989-01-01

Peculiarities of application in X-ray radiography of roentgenographic films, roentgenographic paper, xeroroentgenographic plates and sets of diffusion photographic materials are considered. It is shown that the use of diffusion photographic materials for X-ray radiography permits to reduce the process labour consumption and to considerably reduce the time for the obtaining of a dry positive image and also to reduce the consumption of silver, but the image will preserve high information content. Selts of diffusion photographic materials are developed, which contain bromoiodosilver negative material with silver spraying of 2-3 g/m 3 and transparent positive material on Dacron basis. Prospects of application of sets of diffusion photographic materials in the practice of rapid X-ray radiography to solve the problems of industrial X-ray defectoscopy are panted out

Materials science with SR using x-ray imaging

International Nuclear Information System (INIS)

Kuriyama, Masao

1990-01-01

Some examples of applications of synchrotron radiation to materials science demonstrate the importance of microstructure information within structural as well as functional materials in order to control their properties and quality as designed for industrial purposes. To collect such information, x-ray imaging in quasi real time is required in either the microradiographic mode or the diffraction (in transmission) mode. New measurement technologies based on imaging are applied to polycrystalline materials, single crystal materials and multilayered device materials to illustrate what kind of synchrotron radiation facility is most desirable for materials science and engineering. (author)

In-Line Phase-Contrast X-ray Imaging and Tomography for Materials Science.

Science.gov (United States)

Mayo, Sheridan C; Stevenson, Andrew W; Wilkins, Stephen W

2012-05-24

X-ray phase-contrast imaging and tomography make use of the refraction of X-rays by the sample in image formation. This provides considerable additional information in the image compared to conventional X-ray imaging methods, which rely solely on X-ray absorption by the sample. Phase-contrast imaging highlights edges and internal boundaries of a sample and is thus complementary to absorption contrast, which is more sensitive to the bulk of the sample. Phase-contrast can also be used to image low-density materials, which do not absorb X-rays sufficiently to form a conventional X-ray image. In the context of materials science, X-ray phase-contrast imaging and tomography have particular value in the 2D and 3D characterization of low-density materials, the detection of cracks and voids and the analysis of composites and multiphase materials where the different components have similar X-ray attenuation coefficients. Here we review the use of phase-contrast imaging and tomography for a wide variety of materials science characterization problems using both synchrotron and laboratory sources and further demonstrate the particular benefits of phase contrast in the laboratory setting with a series of case studies.

A NEW HIGH-RESOLUTION ELEVATION MODEL OF GREENLAND DERIVED FROM TANDEM-X

Directory of Open Access Journals (Sweden)

B. Wessel

2016-06-01

Full Text Available In this paper we present for the first time the new digital elevation model (DEM for Greenland produced by the TanDEM-X (TerraSAR add-on for digital elevation measurement mission. The new, full coverage DEM of Greenland has a resolution of 0.4 arc seconds corresponding to 12 m. It is composed of more than 7.000 interferometric synthetic aperture radar (InSAR DEM scenes. X-Band SAR penetrates the snow and ice pack by several meters depending on the structures within the snow, the acquisition parameters, and the dielectricity constant of the medium. Hence, the resulting SAR measurements do not represent the surface but the elevation of the mean phase center of the backscattered signal. Special adaptations on the nominal TanDEM-X DEM generation are conducted to maintain these characteristics and not to raise or even deform the DEM to surface reference data. For the block adjustment, only on the outer coastal regions ICESat (Ice, Cloud, and land Elevation Satellite elevations as ground control points (GCPs are used where mostly rock and surface scattering predominates. Comparisons with ICESat data and snow facies are performed. In the inner ice and snow pack, the final X-Band InSAR DEM of Greenland lies up to 10 m below the ICESat measurements. At the outer coastal regions it corresponds well with the GCPs. The resulting DEM is outstanding due to its resolution, accuracy and full coverage. It provides a high resolution dataset as basis for research on climate change in the arctic.

Effect of Sn Composition in Ge1- x Sn x Layers Grown by Using Rapid Thermal Chemical Vapor Deposition

Science.gov (United States)

Kil, Yeon-Ho; Kang, Sukill; Jeong, Tae Soo; Shim, Kyu-Hwan; Kim, Dae-Jung; Choi, Yong-Dae; Kim, Mi Joung; Kim, Taek Sung

2018-05-01

The Ge1- x Sn x layers were grown by using rapid thermal chemical-vapor deposition (RTCVD) on boron-doped p-type Si (100) substrates with Sn compositions up to x = 0.83%. In order to obtain effect of the Sn composition on the structural and the optical characteristics, we utilized highresolution X-ray diffraction (HR-XRD), etch pit density (EPD), atomic force microscopy (AFM), Raman spectroscopy, and photocurrent (PC) spectra. The Sn compositions in the Ge1- x Sn x layers were found to be of x = 0.00%, 0.51%, 0.65%, and 0.83%. The root-mean-square (RMS) of the surface roughness of the Ge1- x Sn x layer increased from 2.02 nm to 3.40 nm as the Sn composition was increased from 0.51% to 0.83%, and EPD was on the order of 108 cm-2. The Raman spectra consist of only one strong peak near 300 cm-1, which is assigned to the Ge-Ge LO peaks and the Raman peaks shift to the wave number with increasing Sn composition. Photocurrent spectra show near energy band gap peaks and their peak energies decrease with increasing Sn composition due to band-gap bowing in the Ge1- x Sn x layer. An increase in the band gap bowing parameter was observed with increasing Sn composition.

Proposal to DOE Basic Energy Sciences Ultrafast X-ray science facility at the Advanced Light Source

CERN Document Server

Schönlein, R W; Alivisatos, A P; Belkacem, A; Berrah, N; Bozek, J; Bressler, C; Cavalleri, A; Chang, Z; Chergui, M; Falcone, R W; Glover, T E; Heimann, P A; Hepburn, J; Larsson, J; Lee, R W; McCusker, J; Padmore, H A; Pattison, P; Pratt, S T; Robin, D W; Schlüter, Ross D; Shank, C V; Wark, J; Zholents, A A; Zolotorev, M S

2001-01-01

We propose to develop a true user facility for ultrafast x-ray science at the Advanced Light Source. This facility will be unique in the world, and will fill a critical need for the growing ultrafast x-ray research community. The development of this facility builds upon the expertise from long-standing research efforts in ultrafast x-ray spectroscopy and the development of femtosecond x-ray sources and techniques at both the Lawrence Berkeley National Laboratory and at U.C. Berkeley. In particular, the technical feasibility of a femtosecond x-ray beamline at the ALS has already been demonstrated, and existing ultrafast laser technology will enable such a beamline to operate near the practical limit for femtosecond x-ray flux and brightness from a 3rd generation synchrotron.

Proposal to DOE Basic Energy Sciences: Ultrafast X-ray science facility at the Advanced Light Source

Energy Technology Data Exchange (ETDEWEB)

Schoenlein, Robert W.; Falcone, Roger W.; Abela, R.; Alivisatos, A.P.; Belkacem, A.; Berrah, N.; Bozek, J.; Bressler, C.; Cavalleri, A.; Chergui, M.; Glover, T.E.; Heimann, P.A.; Hepburn, J.; Larsson, J.; Lee, R.W.; McCusker, J.; Padmore, H.A.; Pattison, P.; Pratt, S.T.; Shank, C.V.; Wark, J.; Chang, Z.; Robin, D.W.; Schlueter, R.D.; Zholents, A.A.; Zolotorev, M.S.

2001-12-12

We propose to develop a true user facility for ultrafast x-ray science at the Advanced Light Source. This facility will be unique in the world, and will fill a critical need for the growing ultrafast x-ray research community. The development of this facility builds upon the expertise from long-standing research efforts in ultrafast x-ray spectroscopy and the development of femtosecond x-ray sources and techniques at both the Lawrence Berkeley National Laboratory and at U.C. Berkeley. In particular, the technical feasibility of a femtosecond x-ray beamline at the ALS has already been demonstrated, and existing ultrafast laser technology will enable such a beamline to operate near the practical limit for femtosecond x-ray flux and brightness from a 3rd generation synchrotron.

Proposal to DOE Basic Energy Sciences: Ultrafast X-ray science facility at the Advanced Light Source

International Nuclear Information System (INIS)

Schoenlein, Robert W.; Falcone, Roger W.; Abela, R.; Alivisatos, A.P.; Belkacem, A.; Berrah, N.; Bozek, J.; Bressler, C.; Cavalleri, A.; Chergui, M.; Glover, T.E.; Heimann, P.A.; Hepburn, J.; Larsson, J.; Lee, R.W.; McCusker, J.; Padmore, H.A.; Pattison, P.; Pratt, S.T.; Shank, C.V.; Wark, J.; Chang, Z.; Robin, D.W.; Schlueter, R.D.; Zholents, A.A.; Zolotorev, M.S.

2001-01-01

We propose to develop a true user facility for ultrafast x-ray science at the Advanced Light Source. This facility will be unique in the world, and will fill a critical need for the growing ultrafast x-ray research community. The development of this facility builds upon the expertise from long-standing research efforts in ultrafast x-ray spectroscopy and the development of femtosecond x-ray sources and techniques at both the Lawrence Berkeley National Laboratory and at U.C. Berkeley. In particular, the technical feasibility of a femtosecond x-ray beamline at the ALS has already been demonstrated, and existing ultrafast laser technology will enable such a beamline to operate near the practical limit for femtosecond x-ray flux and brightness from a 3rd generation synchrotron

Rapid characterization of a nanomaterial structure using X-ray reciprocal-lattice-space imaging

International Nuclear Information System (INIS)

Sakata, Osami; Yoshimoto, Mamoru; Miki, Kazushi

2006-01-01

The X-ray reciprocal-lattice-space imaging method is able to record the reciprocal-lattice-space of nanostructure by sample-and-detector fixed geometry. This method was developed by the surface structure analysis beam line BL13XU of SPring-8. Outline of the X-ray diffraction method and basic principles of the X-ray reciprocal-lattice-space imaging method, and application examples are stated. The method is able to find out the Bragg conditions of nanostructure of surface in the atmosphere. The reciprocal-lattice of the embedded trace atomic wires was observed. The trace atoms of Bi atomic wires embedded in silicone showed the diffraction signal and image by a short exposure time. This method is useful at rapid non-destructive measurement of nanostructure. (S.Y.)

Molecular tools for bathing water assessment in Europe: Balancing social science research with a rapidly developing environmental science evidence-base.

Science.gov (United States)

Oliver, David M; Hanley, Nick D; van Niekerk, Melanie; Kay, David; Heathwaite, A Louise; Rabinovici, Sharyl J M; Kinzelman, Julie L; Fleming, Lora E; Porter, Jonathan; Shaikh, Sabina; Fish, Rob; Chilton, Sue; Hewitt, Julie; Connolly, Elaine; Cummins, Andy; Glenk, Klaus; McPhail, Calum; McRory, Eric; McVittie, Alistair; Giles, Amanna; Roberts, Suzanne; Simpson, Katherine; Tinch, Dugald; Thairs, Ted; Avery, Lisa M; Vinten, Andy J A; Watts, Bill D; Quilliam, Richard S

2016-02-01

The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science-policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.

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

International Nuclear Information System (INIS)

Tiwari, Manoj K.

2016-01-01

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

Synchrotron x-ray sources and new opportunities in the soil and environmental sciences

International Nuclear Information System (INIS)

Schulze, D.; Anderson, S.; Mattigod, S.

1990-07-01

This report contains the following papers: characteristics of the advanced photon source and comparison with existing synchrotron facilities; x-ray absorption spectroscopy: EXAFS and XANES -- A versatile tool to study the atomic and electronic structure of materials; applications of x-ray spectroscopy and anomalous scattering experiments in the soil and environmental sciences; X-ray fluorescence microprobe and microtomography

Quantitative evaluation of the disintegration of orally rapid disintegrating tablets by X-ray computed tomography.

Science.gov (United States)

Otsuka, Makoto; Yamanaka, Azusa; Uchino, Tomohiro; Otsuka, Kuniko; Sadamoto, Kiyomi; Ohshima, Hiroyuki

2012-01-01

To measure the rapid disintegration of Oral Disintegrating Tablets (ODT), a new test (XCT) was developed using X-ray computing tomography (X-ray CT). Placebo ODT, rapid disintegration candy (RDC) and Gaster®-D-Tablets (GAS) were used as model samples. All these ODTs were used to measure oral disintegration time (DT) in distilled water at 37±2°C by XCT. DTs were affected by the width of mesh screens, and degree to which the tablet holder vibrated from air bubbles. An in-vivo tablet disintegration test was performed for RDC using 11 volunteers. DT by the in-vivo method was significantly longer than that using the conventional tester. The experimental conditions for XCT such as the width of the mesh screen and degree of vibration were adjusted to be consistent with human DT values. Since DTs by the XCT method were almost the same as the human data, this method was able to quantitatively evaluate the rapid disintegration of ODT under the same conditions as inside the oral cavity. The DTs of four commercially available ODTs were comparatively evaluated by the XCT method, conventional tablet disintegration test and in-vivo method.

Applications of Novel X-Ray Imaging Modalities in Food Science

DEFF Research Database (Denmark)

Nielsen, Mikkel Schou

science for understanding and designing food products. In both of these aspects, X-ray imaging methods such as radiography and computed tomography provide a non-destructive solution. However, since the conventional attenuation-based modality suers from poor contrast in soft matter materials, modalities...... with improved contrast are needed. Two possible candidates in this regard are the novel X-ray phase-contrast and X-ray dark-eld imaging modalities. The contrast in phase-contrast imaging is based on dierences in electron density which is especially useful for soft matter materials whereas dark-eld imaging....... Furthermore, the process of translating the image in image analysis was addressed. For improved handling of multimodal image data, a multivariate segmentation scheme of multimodal X-ray tomography data was implemented. Finally, quantitative data analysis was applied for treating the images. Quantitative...

R5 strains of human immunodeficiency virus type 1 from rapid progressors lacking X4 strains do not possess X4-type pathogenicity in human thymus

NARCIS (Netherlands)

Berkowitz, R. D.; van't Wout, A. B.; Kootstra, N. A.; Moreno, M. E.; Linquist-Stepps, V. D.; Bare, C.; Stoddart, C. A.; Schuitemaker, H.; McCune, J. M.

1999-01-01

Some individuals infected with only R5 strains of human immunodeficiency virus type 1 progress to AIDS as quickly as individuals harboring X4 strains. We determined that three R5 viruses were much less pathogenic than an X4 virus in SCID-hu Thy/Liv mice, suggesting that R5 virus-mediated rapid

RAPID SPECTRAL CHANGES OF CYGNUS X-1 IN THE LOW/HARD STATE WITH SUZAKU

Energy Technology Data Exchange (ETDEWEB)

Yamada, S.; Makishima, K. [Cosmic Radiation Laboratory, Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-0198 (Japan); Negoro, H. [Department of Physics, College of Science and Technology, Nihon University, 1-8 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Torii, S.; Noda, H. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Mineshige, S. [Department of Astronomy, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)

2013-04-20

Rapid spectral changes in the hard X-ray on a timescale down to {approx}0.1 s are studied by applying a ''shot analysis'' technique to the Suzaku observations of the black hole binary Cygnus X-1, performed on 2008 April 18 during the low/hard state. We successfully obtained the shot profiles, covering 10-200 keV with the Suzaku HXD-PIN and HXD-GSO detector. It is notable that the 100-200 keV shot profile is acquired for the first time owing to the HXD-GSO detector. The intensity changes in a time-symmetric way, though the hardness changes in a time-asymmetric way. When the shot-phase-resolved spectra are quantified with the Compton model, the Compton y-parameter and the electron temperature are found to decrease gradually through the rising phase of the shot, while the optical depth appears to increase. All the parameters return to their time-averaged values immediately within 0.1 s past the shot peak. We have not only confirmed this feature previously found in energies below {approx}60 keV, but also found that the spectral change is more prominent in energies above {approx}100 keV, implying the existence of some instant mechanism for direct entropy production. We discuss possible interpretations of the rapid spectral changes in the hard X-ray band.

PREFACE: Buried Interface Sciences with X-rays and Neutrons 2010

Science.gov (United States)

Sakurai, Kenji

2011-09-01

The 2010 summer workshop on buried interface science with x-rays and neutrons was held at Nagoya University, Japan, on 25-27 July 2010. The workshop was organized by the Japan Applied Physics Society, which established a group to develop the research field of studying buried function interfaces with x-rays and neutrons. The workshop was the latest in a series held since 2001; Tsukuba (December 2001), Niigata (September 2002), Nagoya (July 2003), Tsukuba (July 2004), Saitama (March 2005), Yokohama (July 2006), Kusatsu (August 2006), Tokyo (December 2006), Sendai (July 2007), Sapporo (September 2007), Tokyo (December 2007), Tokyo-Akihabara (July 2009) and Hiratsuka (March 2010). The 2010 summer workshop had 64 participants and 34 presentations. Interfaces mark the boundaries of different material systems at which many interesting phenomena take place, thus making it extremely important to design, fabricate and analyse the structures of interfaces at both the atomic and macroscopic scale. For many applications, devices are prepared in the form of multi-layered thin films, with the result that interfaces are not exposed but buried under multiple layers. Because of such buried conditions, it is generally not easy to analyse such interfaces. In certain cases, for example, when the thin surface layer is not a solid but a liquid such as water, scientists can observe the atomic arrangement of the liquid-solid interface directly by using a scanning probe microscope, of which the tip is soaked in water. However, it has become clear that the use of a stylus tip positioned extremely close to the interface might change the structure of the water molecules. Therefore it is absolutely crucial to develop non-contact, non-destructive probes for buried interfaces. It is known that analysis using x-rays and neutrons is one of the most powerful tools for exploring near-surface structures including interfaces buried under several layers. In particular, x-ray analysis using 3rd

Prototyping a Global Soft X-Ray Imaging Instrument for Heliophysics, Planetary Science, and Astrophysics Science

Science.gov (United States)

Collier, M. R.; Porter, F. S.; Sibeck, D. G.; Carter, J. A.; Chiao, M. P.; Chornay, D. J.; Cravens, T.; Galeazzi, M.; Keller, J. W.; Koutroumpa, D.;

Prototyping a Global Soft X-ray Imaging Instrument for Heliophysics, Planetary Science, and Astrophysics Science

Science.gov (United States)

Collier, Michael R.; Porter, F. Scott; Sibeck, David G.; Carter, Jenny A.; Chiao, Meng P.; Chornay, Dennis J.; Cravens, Thomas; Galeazzi, Massimiliano; Keller, John W.; Koutroumpa, Dimitra;

Rapid SAR and GPS Measurements and Models for Hazard Science and Situational Awareness

Science.gov (United States)

Owen, S. E.; Yun, S. H.; Hua, H.; Agram, P. S.; Liu, Z.; Moore, A. W.; Rosen, P. A.; Simons, M.; Webb, F.; Linick, J.; Fielding, E. J.; Lundgren, P.; Sacco, G. F.; Polet, J.; Manipon, G.

2016-12-01

The Advanced Rapid Imaging and Analysis (ARIA) project for Natural Hazards is focused on rapidly generating higher level geodetic imaging products and placing them in the hands of the solid earth science and local, national, and international natural hazard communities by providing science product generation, exploration, and delivery capabilities at an operational level. Space-based geodetic measurement techniques such as Interferometric Synthetic Aperture Radar (InSAR), Differential Global Positioning System (DGPS), SAR-based change detection, and image pixel tracking have recently become critical additions to our toolset for understanding and mapping the damage caused by earthquakes, volcanic eruptions, landslides, and floods. Analyses of these data sets are still largely handcrafted following each event and are not generated rapidly and reliably enough for response to natural disasters or for timely analysis of large data sets. The ARIA project, a joint venture co-sponsored by California Institute of Technology (Caltech) and by NASA through the Jet Propulsion Laboratory (JPL), has been capturing the knowledge applied to these responses and building it into an automated infrastructure to generate imaging products in near real-time that can improve situational awareness for disaster response. In addition, the ARIA project is developing the capabilities to provide automated imaging and analysis capabilities necessary to keep up with the imminent increase in raw data from geodetic imaging missions planned for launch by NASA, as well as international space agencies. We will present the progress we have made on automating the analysis of SAR data for hazard monitoring and response using data from Sentinel 1a/b as well as continuous GPS stations. Since the beginning of our project, our team has imaged events and generated response products for events around the world. These response products have enabled many conversations with those in the disaster response community

Current-induced metal-insulator transition in VO x thin film prepared by rapid-thermal-annealing

International Nuclear Information System (INIS)

Cho, Choong-Rae; Cho, SungIl; Vadim, Sidorkin; Jung, Ranju; Yoo, Inkyeong

2006-01-01

The phenomenon of metal-insulator transition (MIT) in polycrystalline VO x thin films and their preparations have been studied. The films were prepared by sputtering of vanadium thin films succeeded by Rapid Thermal Annealing (RTA) in oxygen ambient at 500 deg. C. Crystalline, compositional, and morphological characterizations reveal a continuous change of phase from vanadium metal to the highest oxide phase, V 2 O 5 , with the time of annealing. Electrical MIT switching has been observed in these films. Sweeping mode, electrode area, and temperature dependent MIT has been studied in Pt/VO x /Pt vertical structure. The important parameters for MIT in VO x have been found to be the current density and the electric field, which depend on carrier density in the films

Rapid evolution of cancer/testis genes on the X chromosome

Directory of Open Access Journals (Sweden)

Simpson Andrew J

2007-05-01

Full Text Available Abstract Background Cancer/testis (CT genes are normally expressed only in germ cells, but can be activated in the cancer state. This unusual property, together with the finding that many CT proteins elicit an antigenic response in cancer patients, has established a role for this class of genes as targets in immunotherapy regimes. Many families of CT genes have been identified in the human genome, but their biological function for the most part remains unclear. While it has been shown that some CT genes are under diversifying selection, this question has not been addressed before for the class as a whole. Results To shed more light on this interesting group of genes, we exploited the generation of a draft chimpanzee (Pan troglodytes genomic sequence to examine CT genes in an organism that is closely related to human, and generated a high-quality, manually curated set of human:chimpanzee CT gene alignments. We find that the chimpanzee genome contains homologues to most of the human CT families, and that the genes are located on the same chromosome and at a similar copy number to those in human. Comparison of putative human:chimpanzee orthologues indicates that CT genes located on chromosome X are diverging faster and are undergoing stronger diversifying selection than those on the autosomes or than a set of control genes on either chromosome X or autosomes. Conclusion Given their high level of diversifying selection, we suggest that CT genes are primarily responsible for the observed rapid evolution of protein-coding genes on the X chromosome.

[Theories of evolution shaping Victorian anthropology. The science-politics of the X-Club, 1860-1872].

Science.gov (United States)

Gondermann, Thomas

2008-01-01

This paper discusses the role that a group of evolutionists, the X-Club, played in the epistemic and institutional transformation of Victorian anthropology in the 1860s. It analyses how anthropology has been brought into line with the theory of evolution, which gained currency at the same time. The X-Club was a highly influential pressure group in the Victorian scientific community. It campaigned for the theory of evolution in several fields of the natural sciences and had a considerable influence on the modernization of the sciences. Yet, this club also intervened in the anthropological discourse of these years. The X-Club's meddling with anthropology led to the latter's evolutionary turn. The introduction of an evolutionary agenda into Victorian anthropology depended not only on the X-Club's theoretical contributions but also on the structural reformation of the discipline. Its campaigns also aimed at marginalizing the proponents of pre-evolutionary anthropology in its institutions and led to the foundation of a new organization in anthropology: The Anthropological Institute of Great Britain and Ireland. Thus, evolutionary anthropology emerged in the 1860s also as the result of science-politicking rather than just from the transmission of evolutionary concepts through discourse.

Developments in time-resolved high pressure x-ray diffraction using rapid compression and decompression

International Nuclear Information System (INIS)

Smith, Jesse S.; Sinogeikin, Stanislav V.; Lin, Chuanlong; Rod, Eric; Bai, Ligang; Shen, Guoyin

2015-01-01

Complementary advances in high pressure research apparatus and techniques make it possible to carry out time-resolved high pressure research using what would customarily be considered static high pressure apparatus. This work specifically explores time-resolved high pressure x-ray diffraction with rapid compression and/or decompression of a sample in a diamond anvil cell. Key aspects of the synchrotron beamline and ancillary equipment are presented, including source considerations, rapid (de)compression apparatus, high frequency imaging detectors, and software suitable for processing large volumes of data. A number of examples are presented, including fast equation of state measurements, compression rate dependent synthesis of metastable states in silicon and germanium, and ultrahigh compression rates using a piezoelectric driven diamond anvil cell

Synchronous x-ray and radio mode switches: a rapid global transformation of the pulsar magnetosphere.

Science.gov (United States)

Hermsen, W; Hessels, J W T; Kuiper, L; van Leeuwen, J; Mitra, D; de Plaa, J; Rankin, J M; Stappers, B W; Wright, G A E; Basu, R; Alexov, A; Coenen, T; Grießmeier, J-M; Hassall, T E; Karastergiou, A; Keane, E; Kondratiev, V I; Kramer, M; Kuniyoshi, M; Noutsos, A; Serylak, M; Pilia, M; Sobey, C; Weltevrede, P; Zagkouris, K; Asgekar, A; Avruch, I M; Batejat, F; Bell, M E; Bell, M R; Bentum, M J; Bernardi, G; Best, P; Bîrzan, L; Bonafede, A; Breitling, F; Broderick, J; Brüggen, M; Butcher, H R; Ciardi, B; Duscha, S; Eislöffel, J; Falcke, H; Fender, R; Ferrari, C; Frieswijk, W; Garrett, M A; de Gasperin, F; de Geus, E; Gunst, A W; Heald, G; Hoeft, M; Horneffer, A; Iacobelli, M; Kuper, G; Maat, P; Macario, G; Markoff, S; McKean, J P; Mevius, M; Miller-Jones, J C A; Morganti, R; Munk, H; Orrú, E; Paas, H; Pandey-Pommier, M; Pandey, V N; Pizzo, R; Polatidis, A G; Rawlings, S; Reich, W; Röttgering, H; Scaife, A M M; Schoenmakers, A; Shulevski, A; Sluman, J; Steinmetz, M; Tagger, M; Tang, Y; Tasse, C; ter Veen, S; Vermeulen, R; van de Brink, R H; van Weeren, R J; Wijers, R A M J; Wise, M W; Wucknitz, O; Yatawatta, S; Zarka, P

2013-01-25

Pulsars emit from low-frequency radio waves up to high-energy gamma-rays, generated anywhere from the stellar surface out to the edge of the magnetosphere. Detecting correlated mode changes across the electromagnetic spectrum is therefore key to understanding the physical relationship among the emission sites. Through simultaneous observations, we detected synchronous switching in the radio and x-ray emission properties of PSR B0943+10. When the pulsar is in a sustained radio-"bright" mode, the x-rays show only an unpulsed, nonthermal component. Conversely, when the pulsar is in a radio-"quiet" mode, the x-ray luminosity more than doubles and a 100% pulsed thermal component is observed along with the nonthermal component. This indicates rapid, global changes to the conditions in the magnetosphere, which challenge all proposed pulsar emission theories.

Submicron x-ray diffraction and its applications to problems in materials and environmental science

Science.gov (United States)

Tamura, N.; Celestre, R. S.; MacDowell, A. A.; Padmore, H. A.; Spolenak, R.; Valek, B. C.; Meier Chang, N.; Manceau, A.; Patel, J. R.

2002-03-01

The availability of high brilliance third generation synchrotron sources together with progress in achromatic focusing optics allows us to add submicron spatial resolution to the conventional century-old x-ray diffraction technique. The new capabilities include the possibility to map in situ, grain orientations, crystalline phase distribution, and full strain/stress tensors at a very local level, by combining white and monochromatic x-ray microbeam diffraction. This is particularly relevant for high technology industry where the understanding of material properties at a microstructural level becomes increasingly important. After describing the latest advances in the submicron x-ray diffraction techniques at the Advanced Light Source, we will give some examples of its application in material science for the measurement of strain/stress in metallic thin films and interconnects. Its use in the field of environmental science will also be discussed.

Submicron X-Ray Diffraction and its Applications to Problems in Materials and Environmental Science

Energy Technology Data Exchange (ETDEWEB)

Patel, J. R.

2002-08-16

The availability of high brilliance 3rd generation synchrotron sources together with progress in achromatic focusing optics allow to add submicron spatial resolution to the conventional century-old X-ray diffraction technique. The new capabilities include the possibility to map in-situ, grain orientations, crystalline phase distribution and full strain/stress tensors at a very local level, by combining white and monochromatic X-ray microbeam diffraction. This is particularly relevant for high technology industry where the understanding of material properties at a microstructural level becomes increasingly important. After describing the latest advances in the submicron X-ray diffraction techniques at the ALS, we will give some examples of its application in material science for the measurement of strain/stress in metallic thin films and interconnects. Its use in the field of environmental science will also be discussed.

Submicron X-ray diffraction and its applications to problems in materials and environmental science

Energy Technology Data Exchange (ETDEWEB)

Tamura, N.; Celestre, R.S.; MacDowell, A.A.; Padmore, H.A.; Spolenak, R.; Valek, B.C.; Meier Chang, N.; Manceau, A.; Patel, J.R.

2002-03-26

The availability of high brilliance 3rd generation synchrotron sources together with progress in achromatic focusing optics allow to add submicron spatial resolution to the conventional century-old X-ray diffraction technique. The new capabilities include the possibility to map in-situ, grain orientations, crystalline phase distribution and full strain/stress tensors at a very local level, by combining white and monochromatic X-ray microbeam diffraction. This is particularly relevant for high technology industry where the understanding of material properties at a microstructural level becomes increasingly important. After describing the latest advances in the submicron X-ray diffraction techniques at the ALS, we will give some examples of its application in material science for the measurement of strain/stress in metallic thin films and interconnects. Its use in the field of environmental science will also be discussed.

Dilepton distributions at backward rapidities

International Nuclear Information System (INIS)

Betemps, M. A.; Ducati, M. B. Gay; Oliveira, E. G. de

2006-01-01

The dilepton production at backward rapidities in pAu and pp collisions at RHIC and LHC energies is investigated in the dipole approach. The results are shown through the nuclear modification ratio R pA considering transverse momentum and rapidity spectra. The dilepton modification ratio presents interesting behavior at the backward rapidities when compared with the already known forward ones, since it is related with the large x kinematical region that is being probed. The rapidity dependence of the nuclear modification ratio in the dilepton production is strongly dependent on the Bjorken x behavior of the nuclear structure function ratio R F 2 =F 2 A /F 2 p . The R pA transverse momentum dependence at backward rapidities is modified due to the large x nuclear effects: at RHIC energies, for instance, the ratio R pA is reduced as p T increases, presenting an opposite behavior when compared with the forward one. It implies that the dilepton production at backward rapidities should carry information of the nuclear effects at large Bjorken x, as well as that it is useful to investigate the p T dependence of the observables in this kinematical regime

X-ray, neutron, and electron scattering. Report of a materials sciences workshop

International Nuclear Information System (INIS)

1977-08-01

The ERDA Workshop on X-ray, Neutron, and Electron Scattering to assess needs and establish priorities for energy-related basic research on materials. The general goals of the Workshop were: (1) to review various energy technologies where x-ray, neutron, and electron scattering techniques might make significant contributions, (2) to identify present and future materials problems in the energy technologies and translate these problems into requirements for basic research by x-ray, neutron, and electron scattering techniques, (3) to recommend research areas utilizing these three scattering techniques that should be supported by the DPR Materials Sciences Program, and (4) to assign priorities to these research areas

Effect of rapid thermal annealing on InP1−xBix grown by molecular beam epitaxy

International Nuclear Information System (INIS)

Wu, X Y; Wang, K; Pan, W W; Wang, P; Li, Y Y; Song, Y X; Gu, Y; Yue, L; Xu, H; Zhang, Z P; Cui, J; Gong, Q; Wang, S M

2015-01-01

The effect of post-growth rapid thermal annealing on structural and optical properties of InP 1−x Bi x thin films was investigated. InPBi shows good thermal stability up to 500 °C and a modest improvement in photoluminescence (PL) intensity with an unchanged PL spectral feature. Bismuth outdiffusion from InPBi and strain relaxation are observed at about 600 °C. The InPBi sample annealed at 800 °C shows an unexpected PL spectrum with different energy transitions. (paper)

Rapid assay of plutonium in soils by passive L x-ray counting

International Nuclear Information System (INIS)

Gehrke, R.J.; Putnam, M.H.; Goodwin, S.G.; Kynaston, R.L.

1992-05-01

A technique has been developed to rapidly measure the presence of plutonium in soils, filters, smears, and glass waste forms by measuring the uranium L-shell x-ray emissions associated with the decay of plutonium. In addition, the technique can simultaneously acquire spectra of samples and automatically analyze them for the amount of americium, and gamma-ray emitting activation and fission products present. The samples are counted with a large area, thin-window, n-type Ge spectrometer which is equally efficient for the detection of low energy x-rays (>10 key), as well as high-energy gamma rays (>1 MeV). A 8192-channel analyzer is used to acquire the entire photon spectrum at one time. A dual-energy, time-tagged pulser, that is injected into the test input of the preamplifier to monitor the energy scale, detector resolution, and pulse pile-up will be installed in FY-92. The L x-ray portion of each spectrum is analyzed by a linear least-squares spectral fitting technique originally developed for the analysis of spectra from NaI(Tl) detectors. The gamma-ray portion of each spectrum is analyzed by a standard Ge gamma-ray analysis package. Detection limits (also referred to as lower limits of detection) for plutonium in contaminated soils that have been achieved by this technique are reported

Rapid fusion of 2D X-ray fluoroscopy with 3D multislice CT for image-guided electrophysiology procedures

Science.gov (United States)

Zagorchev, Lyubomir; Manzke, Robert; Cury, Ricardo; Reddy, Vivek Y.; Chan, Raymond C.

2007-03-01

Interventional cardiac electrophysiology (EP) procedures are typically performed under X-ray fluoroscopy for visualizing catheters and EP devices relative to other highly-attenuating structures such as the thoracic spine and ribs. These projections do not however contain information about soft-tissue anatomy and there is a recognized need for fusion of conventional fluoroscopy with pre-operatively acquired cardiac multislice computed tomography (MSCT) volumes. Rapid 2D-3D integration in this application would allow for real-time visualization of all catheters present within the thorax in relation to the cardiovascular anatomy visible in MSCT. We present a method for rapid fusion of 2D X-ray fluoroscopy with 3DMSCT that can facilitate EP mapping and interventional procedures by reducing the need for intra-operative contrast injections to visualize heart chambers and specialized systems to track catheters within the cardiovascular anatomy. We use hardware-accelerated ray-casting to compute digitally reconstructed radiographs (DRRs) from the MSCT volume and iteratively optimize the rigid-body pose of the volumetric data to maximize the similarity between the MSCT-derived DRR and the intra-operative X-ray projection data.

Radiological sciences dictionary

CERN Document Server

Dowsett, David

2009-01-01

The Radiological Sciences Dictionary is a rapid reference guide for all hospital staff employed in diagnostic imaging, providing definitions of over 3000 keywords as applied to the technology of diagnostic radiology.Written in a concise and easy to digest form, the dictionary covers a wide variety of subject matter, including:· radiation legislation and measurement · computing and digital imaging terminology· nuclear medicine radionuclides and radiopharmaceuticals· radiographic contrast agents (x-ray, MRI and ultrasound)· definitions used in ultrasound and MRI technology· statistical exp

New opportunities for 3D materials science of polycrystalline materials at the micrometre lengthscale by combined use of X-ray diffraction and X-ray imaging

DEFF Research Database (Denmark)

Ludwig, W.; King, A.; Reischig, P.

2009-01-01

Non-destructive, three-dimensional (3D) characterization of the grain structure in mono-phase polycrystalline materials is an open challenge in material science. Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting possibilities for mapping 3D grain shapes....... A recent extension of this methodology, termed X-ray diffraction contrast tomography (DCT), combines the principles of X-ray diffraction imaging, three-dimensional X-ray diffraction microscopy (3DXRD) and image reconstruction from projections. DCT provides simultaneous access to 3D grain shape...

Ultrashort X-ray pulse science

Energy Technology Data Exchange (ETDEWEB)

Chin, Alan Hap [Univ. of California, Berkeley, CA (US). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

1998-05-01

A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90° Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ~ 300 fs, 30 keV (0.4 Å) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has been demonstrated as a

Ultrashort X-ray pulse science

International Nuclear Information System (INIS)

Chin, A.H.; Lawrence Berkeley National Lab., CA

1998-01-01

A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90 o Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated ∼ 300 fs, 30 keV (0.4 (angstrom)) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has been

Polychromatic X-ray Micro- and Nano-Beam Science and Instrumentation

Science.gov (United States)

Ice, G. E.; Larson, B. C.; Liu, W.; Barabash, R. I.; Specht, E. D.; Pang, J. W. L.; Budai, J. D.; Tischler, J. Z.; Khounsary, A.; Liu, C.; Macrander, A. T.; Assoufid, L.

2007-01-01

Polychromatic x-ray micro- and nano-beam diffraction is an emerging nondestructive tool for the study of local crystalline structure and defect distributions. Both long-standing fundamental materials science issues, and technologically important questions about specific materials systems can be uniquely addressed. Spatial resolution is determined by the beam size at the sample and by a knife-edge technique called differential aperture microscopy that decodes the origin of scattering from along the penetrating x-ray beam. First-generation instrumentation on station 34-ID-E at the Advanced Photon Source (APS) allows for nondestructive automated recovery of the three-dimensional (3D) local crystal phase and orientation. Also recovered are the local elastic-strain and the dislocation tensor distributions. New instrumentation now under development will further extend the applications of polychromatic microdiffraction and will revolutionize materials characterization.

Polychromatic X-ray Micro- and Nano-Beam Science and Instrumentation

International Nuclear Information System (INIS)

Ice, G.E.; Larson, Ben C.; Liu, Wenjun; Barabash, Rozaliya; Specht, Eliot D; Pang, Judy; Budai, John D.; Tischler, Jonathan Zachary; Khounsary, Ali; Liu, Chian; Macrander, Albert T.; Assoufid, Lahsen

2007-01-01

Polychromatic x-ray micro- and nano-beam diffraction is an emerging nondestructive tool for the study of local crystalline structure and defect distributions. Both long-standing fundamental materials science issues, and technologically important questions about specific materials systems can be uniquely addressed. Spatial resolution is determined by the beam size at the sample and by a knife-edge technique called differential aperture microscopy that decodes the origin of scattering from along the penetrating x-ray beam. First-generation instrumentation on station 34-ID-E at the Advanced Photon Source (APS) allows for nondestructive automated recovery of the three-dimensional (3D) local crystal phase and orientation. Also recovered are the local elastic-strain and the dislocation tensor distributions. New instrumentation now under development will further extend the applications of polychromatic microdiffraction and will revolutionize materials characterization

Rapid Development of Bespoke Unmanned Platforms for Atmospheric Science

Science.gov (United States)

Sobester, A.; Johnston, S. J.; Scanlan, J. P.; Hart, E. E.; O'Brien, N. S.

2012-04-01

The effective deployment of airborne atmospheric science instruments often hinges on the development cycle time of a suitable platform, one that is capable of delivering them to the desired altitude range for a specified amount of time, along a pre-determined trajectory. This could be driven by the need to respond rapidly to sudden, unexpected events (e.g., volcano eruptions, nuclear fallout, etc.) or simply to accommodate the iterative design and flight test cycle of the instrument developer. A shorter development cycle time would also afford us the ability to quickly adapt the hardware and control logic in response to unexpected results during an experimental campaign. We report on recent developments aimed at meeting this demand. As part of the Atmospheric Science Through Robotic Aircraft (ASTRA) initiative we have investigated the use of rapid prototyping technologies to this end, both on the 'airframe' of the platform itself and on the on-board systems. We show how fast multi-disciplinary design optimization techniques, coupled with computer-controlled additive manufacturing (3D printing) and laser cutting methods and electronic prototyping (using standard, modular, programmable building blocks) can lead to the delivery of a fully customized platform integrating a given instrument in a timescale of the order of ten days. Specific examples include the design and testing of a balloon-launched glider sensorcraft and a stratospheric balloon system. The 'vehicle' for the latter was built on a 3D printer using a copolymer thermoplastic material and fitted with a sacrificial protective 'cage' laser-cut from an open-cell foam. The data logging, tracking, sensor integration and communications services of the platform were constructed using the .net Gadgeteer open source hardware kit. The flight planning and eventual post-flight recovery of the system is enabled by a generic, stochastic trajectory simulation tool, also developed as part of the ASTRA initiative. This

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences. KRISHNA S INDALKAR. Articles written in Journal of Chemical Sciences. Volume 129 Issue 2 February 2017 pp 141-148 Rapid Communication. Rapid, efficient and eco-friendly procedure for the synthesis of quinoxalines under solvent-free conditions using sulfated ...

New light for science: European X-ray Free Electron Laser

International Nuclear Information System (INIS)

Sobierajski, R.; Lawniczak-Jablonska, K.

2006-01-01

The execution of the X-Ray Free Electron Laser (XFEL) project begins January 2007. The unique combination of the radiation wavelength, pulse duration and peak brightness provided by XFEL will enable to study processes which occur in both atomic scales - time and space. It will create new scientific opportunities in physics, chemistry, biology and material sciences. In the paper the principles of the XFEL radiation generation, technical design and main radiation parameters are described. They are followed by short description of the project organization. (author) [pl

Using zone plates for X-ray microimaging and microspectroscopy in environmental science

Energy Technology Data Exchange (ETDEWEB)

Kemner, K.M.; Yun, W.; Cai, Z. (and others)

1999-01-01

Understanding the transport and ultimate fate of environmental contaminants is of fundamental importance for developing effective remediation strategies and determining the risk associated with the contaminants. Focusing X-rays by using recently developed zone plates allows determination of the spatial distribution and chemical speciation of contaminants at the micron and submicron length scales. This ability is essential for studying the microscopic physical, geological, chemical, and biological interfaces that play a crucial role in determining contaminant fate and mobility. The following is an overview of some current problems in environmental science that are being addressed with synchrotron-based X-ray microimaging and microspectroscopy. (au) 7 refs.

Using zone plates for X-ray microimaging and microspectroscopy in environmental science

Energy Technology Data Exchange (ETDEWEB)

Kemner, K.M.; Yun, W.; Cai, Z. [and others

1999-11-01

Understanding the transport and ultimate fate of environmental contaminants is of fundamental importance for developing effective remediation strategies and determining the risk associated with the contaminants. Focusing X-rays by using recently developed zone plates allows determination of the spatial distribution and chemical speciation of contaminants at the micron and submicron length scales. This ability is essential for studying the microscopic physical, geological, chemical, and biological interfaces that play a crucial role in determining contaminant fate and mobility. The following is an overview of some current problems in environmental science that are being addressed with synchrotron-based X-ray microimaging and microspectroscopy. (au) 7 refs.

Invited article: The fast readout low noise camera as a versatile x-ray detector for time resolved dispersive extended x-ray absorption fine structure and diffraction studies of dynamic problems in materials science, chemistry, and catalysis

International Nuclear Information System (INIS)

Labiche, Jean-Claude; Mathon, Olivier; Pascarelli, Sakura; Newton, Mark A.; Ferre, Gemma Guilera; Curfs, Caroline; Vaughan, Gavin; Homs, Alejandro; Carreiras, David Fernandez

2007-01-01

Originally conceived and developed at the European Synchrotron Radiation Facility (ESRF) as an 'area' detector for rapid x-ray imaging studies, the fast readout low noise (FReLoN) detector of the ESRF [J.-C. Labiche, ESRF Newsletter 25, 41 (1996)] has been demonstrated to be a highly versatile and unique detector. Charge coupled device (CCD) cameras at present available on the public market offer either a high dynamic range or a high readout speed. A compromise between signal dynamic range and readout speed is always sought. The parameters of the commercial cameras can sometimes be tuned, in order to better fulfill the needs of specific experiments, but in general these cameras have a poor duty cycle (i.e., the signal integration time is much smaller than the readout time). In order to address scientific problems such as time resolved experiments at the ESRF, a FReLoN camera has been developed by the Instrument Support Group at ESRF. This camera is a low noise CCD camera that combines high dynamic range, high readout speed, accuracy, and improved duty cycle in a single image. In this paper, we show its application in a quasi-one-dimensional sense to dynamic problems in materials science, catalysis, and chemistry that require data acquisition on a time scale of milliseconds or a few tens of milliseconds. It is demonstrated that in this mode the FReLoN can be applied equally to the investigation of rapid changes in long range order (via diffraction) and local order (via energy dispersive extended x-ray absorption fine structure) and in situations of x-ray hardness and flux beyond the capacity of other detectors

[Rapidly progressive puberty in a patient with mosaic Turner syndrome: a case report and literature review].

Science.gov (United States)

Liang, Y; Wei, H; Yu, X; Huang, W; Luo, X P

2017-02-02

Objective: To explore the clinical characteristics of diagnosis and treatment in patients with Turner syndrome and rapidly progressive puberty. Method: A rare case of rapidly progressive puberty in Turner syndrome with a mosaic karyotype of 45, X/46, X, del(X)(p21)(80%/20%)was diagnosed at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology in January. 2015. Clinical characteristics and the related literature were reviewed. Original papers on precocious puberty or rapidly progressive puberty in Turner syndrome, published until Apr. 2016 were retrieved at PubMed and CNKI databases by the use of the key words "Turner syndrome" , "precocious puberty" and "rapidly progressive puberty" . Result: The patient was born at term with birth weight of 2 450 g and was diagnosed with SGA at 3 years of age for the first evaluating of growth and development. Then recombined human growth hormone (rhGH )was given at 4 years of age due to short stature (heightTurner syndrome is reported. Although short stature and ovarian dysgenesis are common in TS, precocious puberty may occur in TS, which is liable to cause delayed diagnosis and misdiagnosis. Careful examination is recommended for patients with unusual growth pattern, even though girls have normal height in accord with standard growth curve or spontaneous puberty. Evaluation for TS and subsequent investigation should be prompted.

Rapid thermal processing chamber for in-situ x-ray diffraction

International Nuclear Information System (INIS)

Ahmad, Md. Imteyaz; Van Campen, Douglas G.; Yu, Jiafan; Pool, Vanessa L.; Van Hest, Maikel F. A. M.; Toney, Michael F.; Fields, Jeremy D.; Parilla, Philip A.; Ginley, David S.

2015-01-01

Rapid thermal processing (RTP) is widely used for processing a variety of materials, including electronics and photovoltaics. Presently, optimization of RTP is done primarily based on ex-situ studies. As a consequence, the precise reaction pathways and phase progression during the RTP remain unclear. More awareness of the reaction pathways would better enable process optimization and foster increased adoption of RTP, which offers numerous advantages for synthesis of a broad range of materials systems. To achieve this, we have designed and developed a RTP instrument that enables real-time collection of X-ray diffraction data with intervals as short as 100 ms, while heating with ramp rates up to 100 °Cs −1 , and with a maximum operating temperature of 1200 °C. The system is portable and can be installed on a synchrotron beamline. The unique capabilities of this instrument are demonstrated with in-situ characterization of a Bi 2 O 3 -SiO 2 glass frit obtained during heating with ramp rates 5 °C s −1 and 100 °C s −1 , revealing numerous phase changes

Cool Science: K-12 Climate Change Art Displayed on Buses

Science.gov (United States)

Chen, R. F.; Lustick, D. S.; Lohmeier, J.; Thompson, S. R.

2015-12-01

Cool science is an art contest where K12 students create placards (7" x 22") to educate the public about climate change. Students are prompted to create their artwork in response to questions such as: What is the evidence for climate change? How does climate change impact your local community? What can you do to reduce the impacts of climate change? In each of three years, 500-600 student entrees have been submitted from more than 12 school districts across Massachusetts. A panel of judges including scientists, artists, rapid transit representatives, and educators chooses elementary, middle, and high school winners. Winners (6), runners-up (6), and honorable mentions (12) and their families and teachers are invited to an annual Cool Science Award Ceremony to be recognized and view winning artwork. All winning artwork is posted on the Cool Science website. The winning artwork (2 per grade band) is converted into placards (11" x 28") and posters (2.5' x 12') that are placed on the inside (placards) and outside (posters) of buses. Posters are displayed for one month. So far, Cool Science was implemented in Lowell, MA where over 5000 public viewers see the posters daily on the sides of Lowell Rapid Transit Authority (LRTA) buses, making approximately 1,000,000 impressions per year. Cool Science acts to increase climate literacy in children as well as the public, and as such promotes intergenerational learning. Using art in conjunction with science learning about climate change appears to be effective at engaging not just traditionally high achieving science students, but also those interested in the creative arts. Hearing winners' stories about how they created their artwork and what this contest meant to them supports the idea that Cool Science attracts a wide diversity of students. Parents discuss climate change with their children. Multiple press releases announcing the winners further promotes the awareness of climate change throughout school districts and their

Application of X-ray topography to USSR and Russian space materials science.

Science.gov (United States)

Shul'pina, I L; Prokhorov, I A; Serebryakov, Yu A; Bezbakh, I Zh

2016-05-01

The authors' experience of the application of X-ray diffraction imaging in carrying out space technological experiments on semiconductor crystal growth for the former USSR and for Russia is reported, from the Apollo-Soyuz programme (1975) up to the present day. X-ray topography was applied to examine defects in crystals in order to obtain information on the crystallization conditions and also on their changes under the influence of factors of orbital flight in space vehicles. The data obtained have promoted a deeper understanding of the conditions and mechanisms of crystallization under both microgravity and terrestrial conditions, and have enabled the elaboration of terrestrial methods of highly perfect crystal growth. The use of X-ray topography in space materials science has enriched its methods in the field of digital image processing of growth striations and expanded its possibilities in investigating the inhomogeneity of crystals.

The Impact of Crosstalk in the X-IFU Instrument on Athena Science Cases

Science.gov (United States)

Hartog, R. Den; Peille, P.; Dauser, T.; Jackson, B.; Bandler, S.; Barret, D.; Brand, T.; Herder, J-W Den; Kiviranta, M.; Kuur, J. Van Der;

New generation quantitative x-ray microscopy encompassing phase-contrast

International Nuclear Information System (INIS)

Wilkins, S.W.; Mayo, S.C.; Gureyev, T.E.; Miller, P.R.; Pogany, A.; Stevenson, A.W.; Gao, D.; Davis, T.J.; Parry, D.J.; Paganin, D.

2000-01-01

Full text: We briefly outline a new approach to X-ray ultramicroscopy using projection imaging in a scanning electron microscope (SEM). Compared to earlier approaches, the new approach offers spatial resolution of ≤0.1 micron and includes novel features such as: i) phase contrast to give additional sample information over a wide energy range, rapid phase/amplitude extraction algorithms to enable new real-time modes of microscopic imaging widespread applications are envisaged to fields such as materials science, biomedical research, and microelectronics device inspection. Some illustrative examples are presented. The quantitative methods described here are also very relevant to X-ray projection microscopy using synchrotron sources

Imaging metals in proteins by combining electrophoresis with rapid x-ray fluorescence mapping

International Nuclear Information System (INIS)

Finney, L.; Chishti, Y.; Khare, T.; Giometti, C.; Levina, A.; Lay, P.A.; Vogt, S.

2010-01-01

Growing evidence points toward a very dynamic role for metals in biology. This suggests that physiological circumstance may mandate metal ion redistribution among ligands. This work addresses a critical need for technology that detects, identifies, and measures the metal-containing components of complex biological matrixes. We describe a direct, user-friendly approach for identifying and quantifying metal?protein adducts in complex samples using native- or SDS-PAGE, blotting, and rapid synchrotron X-ray fluorescence mapping with micro-XANES (X-ray absorption near-edge structure) of entire blots. The identification and quantification of each metal bound to a protein spot has been demonstrated, and the technique has been applied in two exemplary cases. In the first, the speciation of the in vitro binding of exogenous chromium to blood serum proteins was influenced markedly by both the oxidation state of chromium exposed to the serum proteins and the treatment conditions, which is of relevance to the biochemistry of Cr dietary supplements. In the second case, in vivo changes in endogenous metal speciation were examined to probe the influence of oxygen depletion on iron speciation in Shewanella oneidensis.

Perspectives of in situ/operando resonant inelastic X-ray scattering in catalytic energy materials science

Energy Technology Data Exchange (ETDEWEB)

Liu, Yi-Sheng; Glans, Per-Anders [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Chuang, Cheng-Hao [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Department of Physics, Tamkang University, Tamsui 250, Taiwan, ROC (China); Kapilashrami, Mukes [Center for Engineering Concepts Development, Department of Mechanical Engineering, University of Maryland, College Park, MD 20742 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Guo, Jinghua, E-mail: jguo@lbl.gov [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064 (United States)

2015-04-15

Highlights: • In-situ/operando soft X-ray RXES and RIXS offer unique perspectives in the energy material science. - Abstract: Growing environmental concerns have renewed the interest for light induced catalytic reactions to synthesize cleaner chemical fuels from syngas. This, however, requires a sound understanding for the dynamics taking place at molecular level as a result of light – matter interaction. We present herein the principles of soft X-ray resonant emission spectroscopy (RXES) and resonant inelastic scattering (RIXS) and the importance of these spectroscopic techniques in materials science in light of their unique ability to emanate characteristic fingerprints on the geometric structure, chemical bonding charge and spin states in addition to chemical sensitivity. The addition of in situ/operando RXES and RIXS capability offers new opportunities to project important material properties and functionalities under conditions nearly identical to the operational modes.

Perspectives of in situ/operando resonant inelastic X-ray scattering in catalytic energy materials science

International Nuclear Information System (INIS)

Liu, Yi-Sheng; Glans, Per-Anders; Chuang, Cheng-Hao; Kapilashrami, Mukes; Guo, Jinghua

2015-01-01

Highlights: • In-situ/operando soft X-ray RXES and RIXS offer unique perspectives in the energy material science. - Abstract: Growing environmental concerns have renewed the interest for light induced catalytic reactions to synthesize cleaner chemical fuels from syngas. This, however, requires a sound understanding for the dynamics taking place at molecular level as a result of light – matter interaction. We present herein the principles of soft X-ray resonant emission spectroscopy (RXES) and resonant inelastic scattering (RIXS) and the importance of these spectroscopic techniques in materials science in light of their unique ability to emanate characteristic fingerprints on the geometric structure, chemical bonding charge and spin states in addition to chemical sensitivity. The addition of in situ/operando RXES and RIXS capability offers new opportunities to project important material properties and functionalities under conditions nearly identical to the operational modes.

The rapid evolution of X-linked male-biased gene expression and the large-X effect in Drosophila yakuba, D. santomea, and their hybrids.

Science.gov (United States)

Llopart, Ana

2012-12-01

The X chromosome has a large effect on hybrid dysfunction, particularly on hybrid male sterility. Although the evidence for this so-called large-X effect is clear, its molecular causes are not yet fully understood. One possibility is that, under certain conditions, evolution proceeds faster in X-linked than in autosomal loci (i.e., faster-X effect) due to both natural selection and their hemizygosity in males, an effect that is expected to be greatest in genes with male-biased expression. Here, I study genome-wide variation in transcript abundance between Drosophila yakuba and D. santomea, within these species and in their hybrid males to evaluate both the faster-X and large-X effects at the level of expression. I find that in X-linked male-biased genes (MBGs) expression evolves faster than in their autosomal counterparts, an effect that is accompanied by a unique reduction in expression polymorphism. This suggests that Darwinian selection is driving expression differences between species, likely enhanced by the hemizygosity of the X chromosome in males. Despite the recent split of the two sister species under study, abundant changes in both cis- and trans-regulatory elements underlie expression divergence in the majority of the genes analyzed, with significant differences in allelic ratios of transcript abundance between the two reciprocal F(1) hybrid males. Cis-trans coevolution at molecular level, evolved shortly after populations become isolated, may therefore contribute to explain the breakdown of the regulation of gene expression in hybrid males. Additionally, the X chromosome plays a large role in this hybrid male misexpression, which affects not only MBG but also, to a lesser degree, nonsex-biased genes. Interestingly, hybrid male misexpression is concentrated mostly in autosomal genes, likely facilitated by the rapid evolution of sex-linked trans-acting factors. I suggest that the faster evolution of X-linked MBGs, at both protein and expression levels

Rapid thermal processing chamber for in-situ x-ray diffraction

Energy Technology Data Exchange (ETDEWEB)

Ahmad, Md. Imteyaz; Van Campen, Douglas G.; Yu, Jiafan; Pool, Vanessa L.; Van Hest, Maikel F. A. M.; Toney, Michael F., E-mail: mftoney@slac.stanford.edu [SSRL, SLAC National Accelerator Laboratory, 2575, Sand Hill Road, Menlo Park, California 94025 (United States); Fields, Jeremy D.; Parilla, Philip A.; Ginley, David S. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

2015-01-15

Rapid thermal processing (RTP) is widely used for processing a variety of materials, including electronics and photovoltaics. Presently, optimization of RTP is done primarily based on ex-situ studies. As a consequence, the precise reaction pathways and phase progression during the RTP remain unclear. More awareness of the reaction pathways would better enable process optimization and foster increased adoption of RTP, which offers numerous advantages for synthesis of a broad range of materials systems. To achieve this, we have designed and developed a RTP instrument that enables real-time collection of X-ray diffraction data with intervals as short as 100 ms, while heating with ramp rates up to 100 °Cs{sup −1}, and with a maximum operating temperature of 1200 °C. The system is portable and can be installed on a synchrotron beamline. The unique capabilities of this instrument are demonstrated with in-situ characterization of a Bi{sub 2}O{sub 3}-SiO{sub 2} glass frit obtained during heating with ramp rates 5 °C s{sup −1} and 100 °C s{sup −1}, revealing numerous phase changes.

Rapid Mapping of Lithiation Dynamics in Transition Metal Oxide Particles with Operando X-ray Absorption Spectroscopy

Science.gov (United States)

Nowack, Lea; Grolimund, Daniel; Samson, Vallerie; Marone, Federica; Wood, Vanessa

2016-02-01

Since the commercialization of lithium ion batteries (LIBs), layered transition metal oxides (LiMO2, where M = Co, Mn, Ni, or mixtures thereof) have been materials of choice for LIB cathodes. During cycling, the transition metals change their oxidation states, an effect that can be tracked by detecting energy shifts in the X-ray absorption near edge structure (XANES) spectrum. X-ray absorption spectroscopy (XAS) can therefore be used to visualize and quantify lithiation kinetics in transition metal oxide cathodes; however, in-situ measurements are often constrained by temporal resolution and X-ray dose, necessitating compromises in the electrochemistry cycling conditions used or the materials examined. We report a combined approach to reduce measurement time and X-ray exposure for operando XAS studies of lithium ion batteries. A highly discretized energy resolution coupled with advanced post-processing enables rapid yet reliable identification of the oxidation state. A full-field microscopy setup provides sub-particle resolution over a large area of battery electrode, enabling the oxidation state within many transition metal oxide particles to be tracked simultaneously. Here, we apply this approach to gain insights into the lithiation kinetics of a commercial, mixed-metal oxide cathode material, nickel cobalt aluminium oxide (NCA), during (dis)charge and its degradation during overcharge.

Science Driven Instrumentation for LCLS-II

Energy Technology Data Exchange (ETDEWEB)

Arthur, John [SLAC National Accelerator Lab., Menlo Park, CA (United States); Bergmann, Uwe [SLAC National Accelerator Lab., Menlo Park, CA (United States); Brunger, Axel [SLAC National Accelerator Lab., Menlo Park, CA (United States); Bostedt, Christoph [SLAC National Accelerator Lab., Menlo Park, CA (United States); Boutet, Sebastien [SLAC National Accelerator Lab., Menlo Park, CA (United States); Bozek, John [SLAC National Accelerator Lab., Menlo Park, CA (United States); Cocco, Daniele [SLAC National Accelerator Lab., Menlo Park, CA (United States); Devereaux, Tom [SLAC National Accelerator Lab., Menlo Park, CA (United States); Ding, Yuantao [SLAC National Accelerator Lab., Menlo Park, CA (United States); Durr, Hermann [SLAC National Accelerator Lab., Menlo Park, CA (United States); Fritz, David [SLAC National Accelerator Lab., Menlo Park, CA (United States); Gaffney, Kelly [SLAC National Accelerator Lab., Menlo Park, CA (United States); Galayda, John [SLAC National Accelerator Lab., Menlo Park, CA (United States); Goldstein, Julia [SLAC National Accelerator Lab., Menlo Park, CA (United States); Guhr, Markus [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hastings, Jerome [SLAC National Accelerator Lab., Menlo Park, CA (United States); Heimann, Philip [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hodgson, Keith [SLAC National Accelerator Lab., Menlo Park, CA (United States); Huang, Zirong [SLAC National Accelerator Lab., Menlo Park, CA (United States); Kelez, Nicholas [SLAC National Accelerator Lab., Menlo Park, CA (United States); Montanez, Paul [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2014-03-24

The world’s first x-ray free electron laser (XFEL), LCLS, has now been operating for more than three years and all six experimental stations are supporting user science and producing high impact scientific results. Other countries are rapidly catching up and a second XFEL, SACLA, is already operating in Japan with others coming on line in Germany, Korea and Switzerland within the next three to five years. In order to increase capability and capacity of LCLS, the Department of Energy has funded LCLS-II.

The discovery of X-ray diffraction by crystals and its great impact on science

International Nuclear Information System (INIS)

Mai Zhenhong

2012-01-01

In April 1912, Friedrich, Knipping and Laue discovered X-ray diffraction in a CuSO 4 crystal. Later, Laue derived the famous Laue equations which explain the diffraction phenomenon. For this, Laue was awarded a Nobel Prize for Physics in 1914. In 1912 W. H. Bragg and W. L. Bragg received news of Laue 's discovery, and from X-ray diffraction experiments in a ZnS crystal they derived the famous Bragg equation. For this work, father and son were together awarded the Nobel Prize for Physics in 1915, To commemorate the 100th anniversary of the discovery of X-ray diffraction, this article reviews the important contributions of the early pioneers and their historic impact on science and technology worldwide. (author)

Rapid detection of toxic metals in non-crushed oyster shells by portable X-ray fluorescence spectrometry

Energy Technology Data Exchange (ETDEWEB)

Chou Ju, E-mail: Ju.Chou@selu.ed [Department of Chemistry and Physics, Southeastern Louisiana University, Hammond, LA 70402 (United States); Clement, Garret; Bursavich, Bradley; Elbers, Don [Department of Chemistry and Physics, Southeastern Louisiana University, Hammond, LA 70402 (United States); Cao Baobao; Zhou Weilie [Advanced Material Research Institute, University of New Orleans, New Orleans, LA 70148 (United States)

2010-06-15

The aim of this study was the multi-elemental detection of toxic metals such as lead (Pb) in non-crushed oyster shells by using a portable X-ray fluorescence (XRF) spectrometer. A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using a portable XRF which provides a quick, quantitative, non-destructive, and cost-effective mean for assessment of oyster shell contamination from Pb. Pb contamination in oyster shells was further confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The results indicated that Pb is distributed in-homogeneously in contaminated shells. Oyster shells have a lamellar structure that could contribute to the high accumulation of Pb on oyster shells. - A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using XRF and contamination of lead on oyster shells was confirmed by XRF and SEM-EDS.

Rapid detection of toxic metals in non-crushed oyster shells by portable X-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Chou Ju; Clement, Garret; Bursavich, Bradley; Elbers, Don; Cao Baobao; Zhou Weilie

2010-01-01

The aim of this study was the multi-elemental detection of toxic metals such as lead (Pb) in non-crushed oyster shells by using a portable X-ray fluorescence (XRF) spectrometer. A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using a portable XRF which provides a quick, quantitative, non-destructive, and cost-effective mean for assessment of oyster shell contamination from Pb. Pb contamination in oyster shells was further confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The results indicated that Pb is distributed in-homogeneously in contaminated shells. Oyster shells have a lamellar structure that could contribute to the high accumulation of Pb on oyster shells. - A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using XRF and contamination of lead on oyster shells was confirmed by XRF and SEM-EDS.

PREFACE: Workshop on 'Buried' Interface Science with X-rays and Neutrons

Science.gov (United States)

Sakurai, Kenji

2007-06-01

The 2007 workshop on `buried' interface science with X-rays and neutrons was held at the Institute of Materials Research, Tohoku University, in Sendai, Japan, on July 22-24, 2007. The workshop was the latest in a series held since 2001; Tsukuba (December 2001), Niigata (September 2002), Nagoya (July 2003), Tsukuba (July 2004), Saitama (March 2005), Yokohama (July 2006), Kusatsu (August 2006) and Tokyo (December 2006). The 2007 workshop had 64 participants and 34 presentations. There are increasing demands for sophisticated metrology in order to observe multilayered materials with nano-structures (dots, wires, etc), which are finding applications in electronic, magnetic, optical and other devices. Unlike many other surface-sensitive methods, X-ray and neutron analysis is known for its ability to see even `buried' function interfaces as well as the surface. It is highly reliable in practice, because the information, which ranges from the atomic to mesoscopic scale, is quantitative and reproducible. The non-destructive nature of this type of analytical method ensures that the same specimen can be measured by other techniques. However, we now realize that the method should be upgraded further to cope with more realistic problems in nano sciences and technologies. In the case of the reflectivity technique and other related methods, which have been the main topics in our workshops over the past 7 years, there are three important directions as illustrated in the Figure. Current X-ray methods can give atomic-scale information for quite a large area on a scale of mm2-cm2. These methods can deliver good statistics for an average, but sometimes we need to be able to see a specific part in nano-scale rather than an average structure. In addition, there is a need to see unstable changing structures and related phenomena in order to understand more about the mechanism of the functioning of nano materials. Quick measurements are therefore important. Furthermore, in order to apply

Rapid simulation of X-ray transmission imaging for baggage inspection via GPU-based ray-tracing

Science.gov (United States)

Gong, Qian; Stoian, Razvan-Ionut; Coccarelli, David S.; Greenberg, Joel A.; Vera, Esteban; Gehm, Michael E.

2018-01-01

We present a pipeline that rapidly simulates X-ray transmission imaging for arbitrary system architectures using GPU-based ray-tracing techniques. The purpose of the pipeline is to enable statistical analysis of threat detection in the context of airline baggage inspection. As a faster alternative to Monte Carlo methods, we adopt a deterministic approach for simulating photoelectric absorption-based imaging. The highly-optimized NVIDIA OptiX API is used to implement ray-tracing, greatly speeding code execution. In addition, we implement the first hierarchical representation structure to determine the interaction path length of rays traversing heterogeneous media described by layered polygons. The accuracy of the pipeline has been validated by comparing simulated data with experimental data collected using a heterogenous phantom and a laboratory X-ray imaging system. On a single computer, our approach allows us to generate over 400 2D transmission projections (125 × 125 pixels per frame) per hour for a bag packed with hundreds of everyday objects. By implementing our approach on cloud-based GPU computing platforms, we find that the same 2D projections of approximately 3.9 million bags can be obtained in a single day using 400 GPU instances, at a cost of only 0.001 per bag.

A 36-pixel superconducting tunnel junction soft X-ray detector for environmental science applications

International Nuclear Information System (INIS)

Friedrich, Stephan; Drury, Owen B.; Cramer, Stephen P.; Green, Peter G.

2006-01-01

We are operating a superconducting tunnel junction detector for high-resolution soft X-ray spectroscopy at the Advanced Biological and Environmental X-ray Facility at the Advanced Light Source synchrotron. We have recently upgraded the instrument from 9 to 36 pixels for increased sensitivity. We have also acquired a new digital signal readout to increase the total count rate capabilities to ∼10 6 counts/s while maintaining a high peak-to-background ratio. We report on the performance of the spectrometer, and discuss speciation measurements of chromium in welding aerosols as a typical application of the instrument in environmental science

A 36-pixel superconducting tunnel junction soft X-ray detector for environmental science applications

Energy Technology Data Exchange (ETDEWEB)

Friedrich, Stephan [Lawrence Livermore National Laboratory, Advanced Detector Group, 7000 East Avenue, L-270, Livermore, CA 94550 (United States) and Lawrence Berkeley National Laboratory, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, Berkeley, CA 94720 (United States)]. E-mail: friedrich1@llnl.gov; Drury, Owen B. [Lawrence Livermore National Laboratory, Advanced Detector Group, 7000 East Avenue, L-270, Livermore, CA 94550 (United States); Lawrence Berkeley National Laboratory, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Cramer, Stephen P. [Lawrence Berkeley National Laboratory, Advanced Biological and Environmental X-ray Facility, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Green, Peter G. [University of California Davis, Department of Civil and Environmental Engineering, 1 Shields Avenue, Davis, CA 95616 (United States)

2006-04-15

We are operating a superconducting tunnel junction detector for high-resolution soft X-ray spectroscopy at the Advanced Biological and Environmental X-ray Facility at the Advanced Light Source synchrotron. We have recently upgraded the instrument from 9 to 36 pixels for increased sensitivity. We have also acquired a new digital signal readout to increase the total count rate capabilities to {approx}10{sup 6} counts/s while maintaining a high peak-to-background ratio. We report on the performance of the spectrometer, and discuss speciation measurements of chromium in welding aerosols as a typical application of the instrument in environmental science.

The Advanced Rapid Imaging and Analysis (ARIA) Project: Providing Standard and On-Demand SAR products for Hazard Science and Hazard Response

Science.gov (United States)

Owen, S. E.; Hua, H.; Rosen, P. A.; Agram, P. S.; Webb, F.; Simons, M.; Yun, S. H.; Sacco, G. F.; Liu, Z.; Fielding, E. J.; Lundgren, P.; Moore, A. W.

2017-12-01

A new era of geodetic imaging arrived with the launch of the ESA Sentinel-1A/B satellites in 2014 and 2016, and with the 2016 confirmation of the NISAR mission, planned for launch in 2021. These missions assure high quality, freely and openly distributed regularly sampled SAR data into the indefinite future. These unprecedented data sets are a watershed for solid earth sciences as we progress towards the goal of ubiquitous InSAR measurements. We now face the challenge of how to best address the massive volumes of data and intensive processing requirements. Should scientists individually process the same data independently themselves? Should a centralized service provider create standard products that all can use? Are there other approaches to accelerate science that are cost effective and efficient? The Advanced Rapid Imaging and Analysis (ARIA) project, a joint venture co-sponsored by California Institute of Technology (Caltech) and by NASA through the Jet Propulsion Laboratory (JPL), is focused on rapidly generating higher level geodetic imaging products and placing them in the hands of the solid earth science and local, national, and international natural hazard communities by providing science product generation, exploration, and delivery capabilities at an operational level. However, there are challenges in defining the optimal InSAR data products for the solid earth science community. In this presentation, we will present our experience with InSAR users, our lessons learned the advantages of on demand and standard products, and our proposal for the most effective path forward.

Direct rapid analysis of trace bioavailable soil macronutrients by chemometrics-assisted energy dispersive X-ray fluorescence and scattering spectrometry

International Nuclear Information System (INIS)

Kaniu, M.I.; Angeyo, K.H.; Mwala, A.K.; Mangala, M.J.

2012-01-01

Highlights: ► Chemometrics-assisted EDXRFS spectroscopy realizes direct, rapid and accurate analysis of trace bioavailable macronutrients in soils. ► The method is minimally invasive, involves little sample preparation, short analysis times and is relatively insensitive to matrix effects. ► This opens up the ability to rapidly characterize large number of samples/matrices with this method. - Abstract: Precision agriculture depends on the knowledge and management of soil quality (SQ), which calls for affordable, simple and rapid but accurate analysis of bioavailable soil nutrients. Conventional SQ analysis methods are tedious and expensive. We demonstrate the utility of a new chemometrics-assisted energy dispersive X-ray fluorescence and scattering (EDXRFS) spectroscopy method we have developed for direct rapid analysis of trace ‘bioavailable’ macronutrients (i.e. C, N, Na, Mg, P) in soils. The method exploits, in addition to X-ray fluorescence, the scatter peaks detected from soil pellets to develop a model for SQ analysis. Spectra were acquired from soil samples held in a Teflon holder analyzed using 109 Cd isotope source EDXRF spectrometer for 200 s. Chemometric techniques namely principal component analysis (PCA), partial least squares (PLS) and artificial neural networks (ANNs) were utilized for pattern recognition based on fluorescence and Compton scatter peaks regions, and to develop multivariate quantitative calibration models based on Compton scatter peak respectively. SQ analyses were realized with high CMD (R 2 > 0.9) and low SEP (0.01% for N and Na, 0.05% for C, 0.08% for Mg and 1.98 μg g −1 for P). Comparison of predicted macronutrients with reference standards using a one-way ANOVA test showed no statistical difference at 95% confidence level. To the best of the authors’ knowledge, this is the first time that an XRF method has demonstrated utility in trace analysis of macronutrients in soil or related matrices.

Actinide science with soft x-ray synchrotron radiation

International Nuclear Information System (INIS)

Shuh, D.

2002-01-01

Several workshops, some dating back more than fifteen years, recognised both the potential scientific impact and opportunities that would be made available by the capability to investigate actinide materials in the vacuum ultraviolet (VUV)/soft X-ray region of the synchrotron radiation (SR) spectrum. This spectral region revolutionized the approach to surface materials chemistry and physics nearly two decades ego. The actinide science community was unable to capitalize on these SR methodologies for the study of actinide materials until recently because of radiological safety concerns. ,The Advanced Light Source (ALS) at LBNL is a third-generation light source providing state-of-the-art performance in the VUV/soft X-ray region. Along with corresponding improvements in detector and vacuum technology, the ALS has rendered experiments with small amounts of actinide materials possible. In particular, it has been the emergence and development of micro-spectroscopic techniques that have enabled investigations of actinide materials at the ALS. The primary methods for the experimental investigation of actinide materials in the VUV/soft X-ray region are the complementary photoelectron spectroscopies, near-edge X-ray absorption fine structure (NEXAFS) and X-ray emission spectroscopy (XES) techniques. Resonant photo-emission is capable of resolving the 5f electron contributions to actinide bonding and can be used to characterise the electronic structure of actinide materials. This technique is clearly a most important methodology afforded by the tunable SR source. Core level and valence band photoelectron spectroscopies are valuable for the characterisation of the electronic properties of actinide materials, as well as for general analytical purposes. High-resolution core-level photo-emission and resonant photo-emission measurements from the a (monoclinic) and δ (FCC) allotropic phases of plutonium metal have been collected on beam line 7.0 at the ALS and the spectra show

Scanning transmission x-ray microscope for materials science spectromicroscopy at the ALS

Energy Technology Data Exchange (ETDEWEB)

Warwick, T.; Seal, S.; Shin, H. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

The brightness of the Advanced Light Source will be exploited by several new instruments for materials science spectromicroscopy over the next year or so. The first of these to become operational is a scanning transmission x-ray microscope with which near edge x-ray absorption spectra (NEXAFS) can be measured on spatial features of sub-micron size. Here the authors describe the instrument as it is presently implemented, its capabilities, some studies made to date and the developments to come. The Scanning Transmission X-ray Microscope makes use of a zone plate lens to produce a small x-ray spot with which to perform absorption spectroscopy through thin samples. The x-ray beam from ALS undulator beamline 7.0 emerges into the microscope vessel through a silicon nitride vacuum window 160nm thick and 300{mu}m square. The vessel is filled with helium at atmospheric pressure. The zone plate lens is illuminated 1mm downstream from the vacuum window and forms an image in first order of a pinhole which is 3m upstream in the beamline. An order sorting aperture passes the first order converging light and blocks the unfocused zero order. The sample is at the focus a few mm downstream of the zone plate and mounted from a scanning piezo stage which rasters in x and y so that an image is formed, pixel by pixel, by an intensity detector behind the sample. Absorption spectra are measured point-by-point as the photon energy is scanned by rotating the diffraction grating in the monochromator and changing the undulator gap.

Rapid Annealing of Iron Implanted Hg(1-x)Cd(x)Te

Science.gov (United States)

1990-03-01

Alnrroveii rFoi’ PubikI Release; distributin tilIntl ted DTICELECTEJUN 12 IMU’ BEest Available Cop, D i ..:6 (J,•, 4iL& , AD Rapid Annealing of Ion...Recently, we have received from Or.J. Dinan of the Night Vision and Electro-optic Army Labs at Fort Belvoir a few electrically uncharacterized Hg

Watching proteins function with time-resolved x-ray crystallography

Science.gov (United States)

Šrajer, Vukica; Schmidt, Marius

2017-09-01

Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115-54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201-41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651-9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237-51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5-20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242-6, Barends et al 2015 Science 350 445-50, Pande et al 2016 Science 352 725-9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline

Two-temperature equilibration in warm dense hydrogen measured with x-ray scattering from the LCLS

Science.gov (United States)

Fletcher, Luke; High Energy Density Sciences Collaboration

2017-10-01

Understanding the properties of warm dense hydrogen plasmas is critical for modeling stellar and planetary interiors, as well as for inertial confinement fusion (ICF) experiments. Of central importance are the electron-ion collision and equilibration times that determine the microscopic properties in a high energy density state. Spectrally and angularly resolved x-ray scattering measurements from fs-laser heated hydrogen have resolved the picosecond evolution and energy relaxation from a two-temperature plasma towards thermodynamic equilibrium in the warm dense matter regime. The interaction of rapidly heated cryogenic hydrogen irradiated by a 400 nm, 5x1017 W/cm2 , 70 fs-laser is visualized with ultra-bright 5.5 kev x-ray pulses from the Linac Coherent Light (LCLS) source in 1 Hz repetition rate pump-probe setting. We demonstrate that the energy relaxation is faster than many classical binary collision theories that use ad hoc cutoff parameters used in the Landau-Spitzer determination of the Coulomb logarithm. This work was supported by the DOE Office of Science, Fusion Energy Science under contract No. SF00515 and supported under FWP 100182 and DOE Office of Basic Energy Sciences, Materials Sciences and Engineering Division, contract DE-AC02-76SF00515.

Liquid Phase Separation and the Aging Effect on Mechanical and Electrical Properties of Laser Rapidly Solidified Cu100−xCrx Alloys

Directory of Open Access Journals (Sweden)

Song-Hua Si

2015-11-01

Full Text Available Duplex structure Cu-Cr alloys are widely used as contact materials. They are generally designed by increasing the Cr content for the hardness improvement, which, however, leads to the unfavorable rapid increase of the electrical resistivity. The solidification behavior of Cu100−xCrx (x = 4.2, 25 and 50 in wt.% alloys prepared by laser rapid solidification is studied here, and their hardness and electrical conductivity after aging are measured. The results show that the Cu-4.2%Cr alloy has the most desirable combination of hardness and conductive properties after aging in comparison with Cu-25%Cr and Cu-50%Cr alloys. Very importantly, a 50% improvement in hardness is achieved with a simultaneous 70% reduction in electrical resistivity. The reason is mainly attributed to the liquid phase separation occurring in the Cu-4.2%Cr alloy, which introduces a large a

Two-dimensional time-resolved x-ray diffraction study of dual phase rapid solidification in steels

Science.gov (United States)

Yonemura, Mitsuharu; Osuki, Takahiro; Terasaki, Hidenori; Komizo, Yuichi; Sato, Masugu; Toyokawa, Hidenori; Nozaki, Akiko

2010-01-01

The high intensity heat source used for fusion welding creates steep thermal gradients of 100 °C/s from 1800 °C. Further, the influence of preferred orientation is important for the observation of a directional solidification that follows the dendrite growth along the ⟨100⟩ direction toward the moving heat source. In the present study, we observed the rapid solidification of weld metal at a time resolution of 0.01-0.1 s by a two-dimensional time-resolved x-ray diffraction (2DTRXRD) system for real welding. The diffraction rings were dynamically observed by 2DTRXRD with synchrotron energy of 18 keV while the arc passes over the irradiation area of the x-rays. The arc power output was 10 V-150 A, and the scan speed of the arc was 1.0 mm/s. The temperature rise in instruments was suppressed by a water-cooled copper plate under the specimen. Further, the temperature distribution of the weld metal was measured by a thermocouple and correlated with the diffraction patterns. Consequently, solidification and solid phase transformation of low carbon steels and stainless steels were observed during rapid cooling by 2DTRXRD. In the low carbon steel, the microstructure is formed in a two step process, (i) formation of crystallites and (ii) increase of crystallinity. In stainless steel, the irregular interface layer of δ/γ in the quenched metal after solidification is expected to show the easy movement of dendrites at a lower temperature. In carbide precipitation stainless steel, it is easy for NbC to grow on δ phase with a little undercooling. Further, a mistlike pattern, which differs from the halo pattern, in the fusion zone gave some indication of the possibilities to observe the nucleation and the early solidification by 2DTRXRD.

Object-oriented classification using quasi-synchronous multispectral images (optical and radar) over agricultural surface

Science.gov (United States)

Marais Sicre, Claire; Baup, Frederic; Fieuzal, Remy

2015-04-01

In the context of climate change (with consequences on temperature and precipitation patterns), persons involved in agricultural management have the imperative to combine: sufficient productivity (as a response of the increment of the necessary foods) and durability of the resources (in order to restrain waste of water, fertilizer or environmental damages). To this end, a detailed knowledge of land use will improve the management of food and water, while preserving the ecosystems. Among the wide range of available monitoring tools, numerous studies demonstrated the interest of satellite images for agricultural mapping. Recently, the launch of several radar and optical sensors offer new perspectives for the multi-wavelength crop monitoring (Terrasar-X, Radarsat-2, Sentinel-1, Landsat-8…) allowing surface survey whatever the cloud conditions. Previous studies have demonstrated the interest of using multi-temporal approaches for crop classification, requiring several images for suitable classification results. Unfortunately, these approaches are limited (due to the satellite orbit cycle) and require waiting several days, week or month before offering an accurate land use map. The objective of this study is to compare the accuracy of object-oriented classification (random forest algorithm combined with vector layer coming from segmentation) to map winter crop (barley, rapeseed, grasslands and wheat) and soil states (bare soils with different surface roughness) using quasi-synchronous images. Satellite data are composed of multi-frequency and multi-polarization (HH, VV, HV and VH) images acquired near the 14th of April, 2010, over a studied area (90km²) located close to Toulouse in France. This is a region of alluvial plains and hills, which are mostly mixed farming and governed by a temperate climate. Remote sensing images are provided by Formosat-2 (04/18), Radarsat-2 (C-band, 04/15), Terrasar-X (X-band, 04/14) and ALOS (L-band, 04/14). Ground data are collected

Proceedings – Mathematical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Proceedings – Mathematical Sciences. OLIVIA X M YAO. Articles written in Proceedings – Mathematical Sciences. Volume 127 Issue 3 June 2017 pp 393-410 Research Article. New modular relations involving cubes of the Göllnitz–Gordon functions · OLIVIA X M YAO · More Details Abstract Fulltext PDF.

Chandra Data Reveal Rapidly Whirling Black Holes

Science.gov (United States)

2008-01-01

A new study using results from NASA's Chandra X-ray Observatory provides one of the best pieces of evidence yet that many supermassive black holes are spinning extremely rapidly. The whirling of these giant black holes drives powerful jets that pump huge amounts of energy into their environment and affects galaxy growth. A team of scientists compared leading theories of jets produced by rotating supermassive black holes with Chandra data. A sampling of nine giant galaxies that exhibit large disturbances in their gaseous atmospheres showed that the central black holes in these galaxies must be spinning at near their maximum rates. People Who Read This Also Read... NASA’s Swift Satellite Catches First Supernova in The Act of Exploding Black Holes Have Simple Feeding Habits Jet Power and Black Hole Assortment Revealed in New Chandra Image Erratic Black Hole Regulates Itself "We think these monster black holes are spinning close to the limit set by Einstein's theory of relativity, which means that they can drag material around them at close to the speed of light," said Rodrigo Nemmen, a visiting graduate student at Penn State University, and lead author of a paper on the new results presented at American Astronomical Society in Austin, Texas. The research reinforces other, less direct methods previously used which have indicated that some stellar and supermassive black holes are spinning rapidly. According to Einstein's theory, a rapidly spinning black hole makes space itself rotate. This effect, coupled with gas spiraling toward the black hole, can produce a rotating, tightly wound vertical tower of magnetic field that flings a large fraction of the inflowing gas away from the vicinity of the black hole in an energetic, high-speed jet. Computer simulations by other authors have suggested that black holes may acquire their rapid spins when galaxies merge, and through the accretion of gas from their surroundings. "Extremely fast spin might be very common for large

Amorphous SiO {sub x} nanowires grown on silicon (100) substrates via rapid thermal process of nanodiamond films

Energy Technology Data Exchange (ETDEWEB)

Liang Xingbo [State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Wang Lei [State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Yang Deren [State Key Lab of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)]. E-mail: mseyang@zju.edu.cn

2006-05-01

Rapid thermal process (RTP) has been carried out on the deposited nanocrystalline diamond (NCD) films. The RTP treatments performed at 800 and 1200 deg. C have been shown to exert prominent influence on the morphology and structure of the NCD films. The loss of material at grain boundaries has been observed at both 800 and 1200 deg. C RTP treatments. Large-scale amorphous SiO {sub x} nanowires with diameters of 30-50 nm and length up to 10 {mu}m were synthesized after RTP treatment at 1200 deg. C for 60 s. The synthesized nanowires were characterized in detail by scanning electron microscopy, transmission electron microscopy, selected area electron diffraction and energy-dispersed X-ray spectrometry analysis. A possible growth mechanism has been proposed to explain the observed phenomenon.

Mapping metals in Parkinson's and normal brain using rapid-scanning x-ray fluorescence

International Nuclear Information System (INIS)

Popescu, Bogdan F Gh; George, Martin J; McCrea, Richard P E; Devon, Richard M; George, Graham N; Hanson, Akela D; Chapman, L Dean; Nichol, Helen; Bergmann, Uwe; Garachtchenko, Alex V; Luening, Katharina; Kelly, Michael E; Harder, Sheri M; Pickering, Ingrid J

2009-01-01

Rapid-scanning x-ray fluorescence (RS-XRF) is a synchrotron technology that maps multiple metals in tissues by employing unique hardware and software to increase scanning speed. RS-XRF was validated by mapping and quantifying iron, zinc and copper in brain slices from Parkinson's disease (PD) and unaffected subjects. Regions and structures in the brain were readily identified by their metal complement and each metal had a unique distribution. Many zinc-rich brain regions were low in iron and vice versa. The location and amount of iron in brain regions known to be affected in PD agreed with analyses using other methods. Sample preparation is simple and standard formalin-fixed autopsy slices are suitable. RS-XRF can simultaneously and non-destructively map and quantify multiple metals and holds great promise to reveal metal pathologies associated with PD and other neurodegenerative diseases as well as diseases of metal metabolism.

Frontiers in X-Ray Science

International Nuclear Information System (INIS)

Young, Linda

2011-01-01

The year 2010 marked the fiftieth anniversary of the optical laser and the first anniversary of the world's first hard x-ray free-electron laser, the Linac Coherent Light Source (LCLS) at SLAC. This exciting, new accelerator-based source of x-rays provides peak brilliances roughly a billion times greater than currently available from synchrotron sources such as the Advanced Photon Source at Argonne, and thus explores a qualitatively different parameter space. This talk will describe the first experiments at the LCLS aimed at understanding the nature of high intensity x-ray interactions, related applications in ultrafast imaging on the atomic scale and sketch nascent plans for the extension of both linac and storage-ring based photon sources.

NuSTAR detection of high-energy X-ray emission and rapid variability from Sagittarius A{sup *} flares

Energy Technology Data Exchange (ETDEWEB)

Barrière, Nicolas M.; Tomsick, John A.; Boggs, Steven E.; Craig, William W.; Zoglauer, Andreas [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Baganoff, Frederick K. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Christensen, Finn E. [DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Kgs. Lyngby (Denmark); Dexter, Jason [Departments of Physics and Astronomy, University of California, Berkeley, CA 94720 (United States); Grefenstette, Brian; Harrison, Fiona A.; Madsen, Kristin K. [Cahill Center for Astronomy and Astrophysics, Caltech, Pasadena, CA 91125 (United States); Hailey, Charles J.; Mori, Kaya; Zhang, Shuo [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Zhang, William W. [X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2014-05-01

Sagittarius A{sup *} harbors the supermassive black hole that lies at the dynamical center of our Galaxy. Sagittarius A{sup *} spends most of its time in a low luminosity emission state but flares frequently in the infrared and X-ray, increasing up to a few hundred fold in brightness for up to a few hours at a time. The physical processes giving rise to the X-ray flares are uncertain. Here we report the detection with the NuSTAR observatory in Summer and Fall 2012 of four low to medium amplitude X-ray flares to energies up to 79 keV. For the first time, we clearly see that the power-law spectrum of Sagittarius A{sup *} X-ray flares extends to high energy, with no evidence for a cutoff. Although the photon index of the absorbed power-law fits are in agreement with past observations, we find a difference between the photon index of two of the flares (significant at the 95% confidence level). The spectra of the two brightest flares (∼55 times quiescence in the 2-10 keV band) are compared to simple physical models in an attempt to identify the main X-ray emission mechanism, but the data do not allow us to significantly discriminate between them. However, we confirm the previous finding that the parameters obtained with synchrotron models are, for the X-ray emission, physically more reasonable than those obtained with inverse Compton models. One flare exhibits large and rapid (<100 s) variability, which, considering the total energy radiated, constrains the location of the flaring region to be within ∼10 Schwarzschild radii of the black hole.

Investigating the Magnetospheres of Rapidly Rotating B-type Stars

Science.gov (United States)

Fletcher, C. L.; Petit, V.; Nazé, Y.; Wade, G. A.; Townsend, R. H.; Owocki, S. P.; Cohen, D. H.; David-Uraz, A.; Shultz, M.

2017-11-01

Recent spectropolarimetric surveys of bright, hot stars have found that ~10% of OB-type stars contain strong (mostly dipolar) surface magnetic fields (~kG). The prominent paradigm describing the interaction between the stellar winds and the surface magnetic field is the magnetically confined wind shock (MCWS) model. In this model, the stellar wind plasma is forced to move along the closed field loops of the magnetic field, colliding at the magnetic equator, and creating a shock. As the shocked material cools radiatively it will emit X-rays. Therefore, X-ray spectroscopy is a key tool in detecting and characterizing the hot wind material confined by the magnetic fields of these stars. Some B-type stars are found to have very short rotational periods. The effects of the rapid rotation on the X-ray production within the magnetosphere have yet to be explored in detail. The added centrifugal force due to rapid rotation is predicted to cause faster wind outflows along the field lines, leading to higher shock temperatures and harder X-rays. However, this is not observed in all rapidly rotating magnetic B-type stars. In order to address this from a theoretical point of view, we use the X-ray Analytical Dynamical Magnetosphere (XADM) model, originally developed for slow rotators, with an implementation of new rapid rotational physics. Using X-ray spectroscopy from ESA's XMM-Newton space telescope, we observed 5 rapidly rotating B-types stars to add to the previous list of observations. Comparing the observed X-ray luminosity and hardness ratio to that predicted by the XADM allows us to determine the role the added centrifugal force plays in the magnetospheric X-ray emission of these stars.

The discovery of X-rays diffraction: From crystals to DNA. A case study to promote understanding of the nature of science and of its interdisciplinary character

International Nuclear Information System (INIS)

Guerra, Francesco; Leone, Matteo; Robotti, Nadia

2015-01-01

The advantages of introducing history of science topics into the teaching of science has been advocated by a large number of scholars within the science education community. One of the main reasons given for using history of science in teaching is its power to promote understanding of the nature of science (NOS). In this respect, the historical case of X-rays diffraction, from the discovery of Max von Laue (1912) to the first X-rays diffraction photographs of DNA (1953), is a case in point for showing that a correct experimental strategy and a favourable theoretical context are not enough to make a scientific discovery.

Proceedings – Mathematical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Proceedings – Mathematical Sciences. Q X Yang. Articles written in Proceedings – Mathematical Sciences. Volume 115 Issue 2 May 2005 pp 191-200. L p -Continuity for Calderón–Zygmund Operator · Q X Yang · More Details Abstract Fulltext PDF. Given a Calderón–Zygmund (- for short) operator , ...

Direct rapid analysis of trace bioavailable soil macronutrients by chemometrics-assisted energy dispersive X-ray fluorescence and scattering spectrometry

Energy Technology Data Exchange (ETDEWEB)

Kaniu, M.I., E-mail: ikaniu@uonbi.ac.ke [Institute of Nuclear Science and Technology, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya); Angeyo, K.H. [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya); Mwala, A.K. [Department of Land Resource Management and Agricultural Technology, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya); Mangala, M.J. [Institute of Nuclear Science and Technology, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya)

2012-06-04

Highlights: Black-Right-Pointing-Pointer Chemometrics-assisted EDXRFS spectroscopy realizes direct, rapid and accurate analysis of trace bioavailable macronutrients in soils. Black-Right-Pointing-Pointer The method is minimally invasive, involves little sample preparation, short analysis times and is relatively insensitive to matrix effects. Black-Right-Pointing-Pointer This opens up the ability to rapidly characterize large number of samples/matrices with this method. - Abstract: Precision agriculture depends on the knowledge and management of soil quality (SQ), which calls for affordable, simple and rapid but accurate analysis of bioavailable soil nutrients. Conventional SQ analysis methods are tedious and expensive. We demonstrate the utility of a new chemometrics-assisted energy dispersive X-ray fluorescence and scattering (EDXRFS) spectroscopy method we have developed for direct rapid analysis of trace 'bioavailable' macronutrients (i.e. C, N, Na, Mg, P) in soils. The method exploits, in addition to X-ray fluorescence, the scatter peaks detected from soil pellets to develop a model for SQ analysis. Spectra were acquired from soil samples held in a Teflon holder analyzed using {sup 109}Cd isotope source EDXRF spectrometer for 200 s. Chemometric techniques namely principal component analysis (PCA), partial least squares (PLS) and artificial neural networks (ANNs) were utilized for pattern recognition based on fluorescence and Compton scatter peaks regions, and to develop multivariate quantitative calibration models based on Compton scatter peak respectively. SQ analyses were realized with high CMD (R{sup 2} > 0.9) and low SEP (0.01% for N and Na, 0.05% for C, 0.08% for Mg and 1.98 {mu}g g{sup -1} for P). Comparison of predicted macronutrients with reference standards using a one-way ANOVA test showed no statistical difference at 95% confidence level. To the best of the authors' knowledge, this is the first time that an XRF method has demonstrated

Research at and Operation of the Materials Science Beamline (X-11) at the National Synchrotron Light Source. Final Report

International Nuclear Information System (INIS)

Sayers, Dale E.

2003-01-01

This is the final report for DOE DE-FG02-89ER45384. An overview of the operational history and status of beamline X-11A at the end of the contract period, and a brief review of the core science program at NCSU and the scientific results of X-11A since the last progress report is also presented

Science in Cinema. Teaching Science Fact through Science Fiction Films.

Science.gov (United States)

Dubeck, Leroy W.; And Others

Many feel that secondary school graduates are not prepared to compete in a world of rapidly expanding technology. High school and college students in the United States often prefer fantasy to science. This book offers a strategy for overcoming student apathy toward the physical sciences by harnessing the power of the cinema. In it, ten popular…

Rapidly variable relatvistic absorption

Science.gov (United States)

Parker, M.; Pinto, C.; Fabian, A.; Lohfink, A.; Buisson, D.; Alston, W.; Jiang, J.

2017-10-01

I will present results from the 1.5Ms XMM-Newton observing campaign on the most X-ray variable AGN, IRAS 13224-3809. We find a series of nine absorption lines with a velocity of 0.24c from an ultra-fast outflow. For the first time, we are able to see extremely rapid variability of the UFO features, and can link this to the X-ray variability from the inner accretion disk. We find a clear flux dependence of the outflow features, suggesting that the wind is ionized by increasing X-ray emission.

X Q TANG

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. X Q TANG. Articles written in Bulletin of Materials Science. Volume 41 Issue 2 April 2018 pp 51. Effect of oxygen vacancies on Li-storage of anatase TiO 2 (001) facets: a first principles study · H CHEN Y H DING X Q TANG W ZHANG J R YIN P ZHANG Y JIANG · More Details ...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 129; Issue 2. Rapid, efficient and eco-friendly procedure for the synthesis of quinoxalines under solvent-free conditions using sulfated polyborate as a recyclable catalyst. KRISHNA S INDALKAR CHETAN K KHATRI GANESH U CHATURBHUJ. Rapid Communication ...

Possibilities and Challenges of Scanning Hard X-ray Spectro-microscopy Techniques in Material Sciences

Directory of Open Access Journals (Sweden)

Andrea Somogyi

2015-06-01

Full Text Available Scanning hard X-ray spectro-microscopic imaging opens unprecedented possibilities in the study of inhomogeneous samples at different length-scales. It gives insight into the spatial variation of the major and minor components, impurities and dopants of the sample, and their chemical and electronic states at micro- and nano-meter scales. Measuring, modelling and understanding novel properties of laterally confined structures are now attainable. The large penetration depth of hard X-rays (several keV to several 10 keV beam energy makes the study of layered and buried structures possible also in in situ and in operando conditions. The combination of different X-ray analytical techniques complementary to scanning spectro-microscopy, such as X-ray diffraction, X-ray excited optical luminescence, secondary ion mass spectrometry (SIMS and nano-SIMS, provides access to optical characteristics and strain and stress distributions. Complex sample environments (temperature, pressure, controlled atmosphere/vacuum, chemical environment are also possible and were demonstrated, and allow as well the combination with other analysis techniques (Raman spectroscopy, infrared imaging, mechanical tensile devices, etc. on precisely the very same area of the sample. The use of the coherence properties of X-rays from synchrotron sources is triggering emerging experimental imaging approaches with nanometer lateral resolution. New fast analytical possibilities pave the way towards statistically significant studies at multi- length-scales and three dimensional tomographic investigations. This paper gives an overview of these techniques and their recent achievements in the field of material sciences.

Watching proteins function with time-resolved x-ray crystallography

Energy Technology Data Exchange (ETDEWEB)

Šrajer, Vukica; Schmidt, Marius

2017-08-22

Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol. 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol. 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We

Watching proteins function with time-resolved x-ray crystallography

International Nuclear Information System (INIS)

Šrajer, Vukica; Schmidt, Marius

2017-01-01

Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron x-ray sources. An expansive database of more than 100 000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al 2005a Methods Mol. Biol . 305 115–54, Schmidt 2008 Ultrashort Laser Pulses in Biology and Medicine (Berlin: Springer) pp 201–41, Neutze and Moffat 2012 Curr. Opin. Struct. Biol . 22 651–9, Šrajer 2014 The Future of Dynamic Structural Science (Berlin: Springer) pp 237–51). In this approach, short and intense x-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron x-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard x-rays (XFELs; 5–20 keV), which provide exceptionally intense, femtosecond x-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al 2014 Science 346 1242–6, Barends et al 2015 Science 350 445–50, Pande et al 2016 Science 352 725–9). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs

Structure, microstructure and microhardness of rapidly solidified Smy(FexNi1-x)4Sb12 (x = 0.45, 0.50, 0.70, 1) thermoelectric compounds

Science.gov (United States)

Artini, C.; Castellero, A.; Baricco, M.; Buscaglia, M. T.; Carlini, R.

2018-05-01

Skutterudites are interesting compounds for thermoelectric applications. The main drawback in the synthesis of skutterudites by solidification of the melt is the occurrence of two peritectic reactions requiring long annealing times to form a single phase. Aim of this work is to investigate an alternative route for synthesis, based on rapid solidification by planar flow casting. The effect of cooling rate on phases formation and composition, as well as on structure, microstructure and mechanical properties of the filled Smy(FexNi1-x)4Sb12 (x = 0.45, 0.50, 0.70, 1) skutterudites was studied. Conversely to slowly cooled ingots, rapidly quenched ribbons show skutterudite as the main phase, suggesting that deep undercooling of the liquid prevents the nucleation of high temperature phases, such as (Fe,Ni)Sb and (Fe,Ni)Sb2. In as-quenched samples, a slightly out of equilibrium Sm content is revealed, which does not alter the position of the p/n boundary; nevertheless, it exerts an influence on crystallographic properties, such as the cell parameter and the shape of the Sb4 rings in the structure. As-quenched ribbons show a fine microstructure of the skutterudite phase (grain size of 2-20 μm), which only moderately coarsens after annealing at 873 K for 4 days. Vickers microhardness values (350-400 HV) of the skutterudite phase in as-quenched ribbons are affected by the presence of softer phases (i.e. Sb), which are homogeneously and finely dispersed within the sample. The skutterudite hardens after annealing as a consequence of a moderate grain growth, which limits the matrix effect due to the presence of additional phases.

High Resolution 3D Earth Observation Data Analysis for Safeguards Activities

International Nuclear Information System (INIS)

D'Angelo, P.; Eineder, M.; Rossi, C.

2015-01-01

This paper provides an overview of the investigations performed in the last three years at DLR and highlights the application of SAR and optical data for 3D analysis in the context of Safeguards. The Research Center Juelich and the adjacent open cut mines were used as main test site, and a comprehensive stack of ascending and descending TerraSAR data was acquired over two years. TerraSAR data acquisition was performed, and various ways to visualize stacks of radar images were evaluated. Building height estimation was performed using a combination of ascending-descending radar images, as well as height-form-shadow, height-from-layover. A tutorial on building signatures from SAR images highlighted the sensor specific imaging characteristics. These topics were particularly relevant in safeguards activity with a ''small-budget'' as only a single image - or a couple - were employed. Interferometric coherence map interpretation allows the detection of used dirt roads. Digital surface models (DSM) were generated from TanDEM-X interferometric data and from optical VHR data. Sub-meterWorldview-2 and GeoEye-1 data was processed into highly detailed DSM with a grid spacing of 1 m, showing building structures. 3D change and volume detection was performed with both optical and radar DSMs. The TanDEM-X DSMs proved useful for volume change detection and computation in mining areas, and down to building level with optical data. Virtual fly-through were found to be a good tool to provide an intuitive understanding of site structure and might be useful for inspector briefing. Tools for most of the above mentioned tasks have been developed for the ENVI environment and can be used by IAEA internally. (author)

Russian science trapped in web of rapid change

International Nuclear Information System (INIS)

Josephson, P.R.

1995-01-01

During the Cold War, Soviet physicists were revered for their contribution to the country's prestige, economic growth, and national security, says Paul Josephson, a professor in the Department of Science, Technology, and Society at Sarah Lawrence College in Bronxville, New York. But the lavish support the Russian physics establishment once received is gone. In fact, the dissolution of the Soviet regime and deepening economic and political crisis have left scientists struggling to maintain their programs and keep institutes open. Internal crisis and the internationalization of science and technology have led to a drain of top Russian scientists in many fields, particularly in mathematics and theoretical physics. The West has responded to these concerns by giving financial aid and sponsoring initiatives designed to keep former Soviet scientists employed either at home or in the United States or Europe. However, the ultimate health of Russian science will depend on internal government reforms and public support, concludes Josephson

Development of an x-ray beam line at the NSLS for studies in materials science using x-ray absorption spectroscopy

International Nuclear Information System (INIS)

Sayers, D.E.

1989-01-01

At the time of the submission of the original proposal more than 7 years ago, the X-11 PRT had set as a goal to develop one of the leading and most comprehensive x-ray absorption beam lines in the world. By any measure we have been successful. As is well documented in previous annual progress report and in the NSLS annual reports, our PRT has been extremely productive in a wide range of topics in materials science, solid state physics, chemistry and biology. Well over 100 papers have been published acknowledging the support of this contract and this continues at a rate of about 30 papers per year and about 20 invited presentations per year. Significant in this report are major studies in high T c compounds, advances in interface studies, new results in premelting phenomena, several pioneering studies in application of XAS to electrochemistry and significant progress in our understanding of the structure of amorphous chalcogenide systems and their photostructural changes

Rapid Analysis of Copper Ore in Pre-Smelter Head Flow Slurry by Portable X-ray Fluorescence.

Science.gov (United States)

Burnett, Brandon J; Lawrence, Neil J; Abourahma, Jehad N; Walker, Edward B

2016-05-01

Copper laden ore is often concentrated using flotation. Before the head flow slurry can be smelted, it is important to know the concentration of copper and contaminants. The concentration of copper and other elements fluctuate significantly in the head flow, often requiring modification of the concentrations in the slurry prior to smelting. A rapid, real-time analytical method is needed to support on-site optimization of the smelter feedstock. A portable, handheld X-ray fluorescence spectrometer was utilized to determine the copper concentration in a head flow suspension at the slurry origin. The method requires only seconds and is reliable for copper concentrations of 2.0-25%, typically encountered in such slurries. © The Author(s) 2016.

The instrumental blank of the Mars Science Laboratory alpha particle X-ray spectrometer

Energy Technology Data Exchange (ETDEWEB)

Campbell, J.L., E-mail: icampbel@uoguelph.ca [Guelph-Waterloo Physics Institute, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada)

2012-10-01

The alpha particle X-ray spectrometers on the Mars exploration rovers Spirit and Opportunity accomplished extensive elemental analysis of the Martian surface through a combination of XRF and PIXE. An advanced APXS is now part of the Mars Science Laboratory's Curiosity rover. APXS spectra contain contributions which enhance elemental peak areas but which do not arise from these elements within the sample under study, thereby introducing error into derived concentrations. A detailed examination of these effects in the MSL APXS enables us to test two schemes for making the necessary corrections.

Rapid spectral and flux time variations in a solar burst observed at various dm-mm wavelengths and at hard x rays

International Nuclear Information System (INIS)

Zodivaz, A.M.; Kaufmann, P.; Correia, E.; Costa, J.E.R.; Takakura, T.; Cliver, E.W.; Tapping, K.F.; Air Force Geophysics Lab., Hanscom AFB, MA; National Research Council of Canada, Ottawa, Ontario)

1986-01-01

A solar burst was observed with high sensitivity and time resolution at cm-mm wavelengths by two different radio observatories (Itapetinga and Algonquin), with high spectral time resolution at dm-mm wavelengths by patrol instruments (Sagamore Hill), and at hard x rays (HXM Hinotori). At the onset of the major burst time structure there was a rapid rise in the spectral turnover frequency (from 5 to 15 GHz), in about 10s, coincident to a reduction of the spectral index in the optically thin part of the spectrum. The burst maxima were not time coincident at the optically thin radio frequencies and at the different hard x ray energy ranges. The profiles at higher radio frequencies exhibited better time coincidence to the high energy x rays. The hardest x ray spectrum (-3) coincided with peak radio emission at the higher frequency (44 GHz). The event appeared to be built up by a first major injection of softer particles followed by other injections of harder particles. Ultrafast time structures were identified as superimposed on the burst emission at the cm-mm high sensitivity data at x rays, with predominant repetition rates ranging from 2.0 to 3.5 Hz

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Science Education Programmes · Women in Science · Committee on Scientific ... Critical Reviews of important fields and Perspective articles in emerging areas will ... work, mandatory for Rapid Communication, and suggest 2 to 3 names of Referees. ... The Jurisdiction for all disputes concerning submitted articles, published ...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences. Wenzhong Cheng. Articles written in Journal of Chemical Sciences. Volume 126 Issue 6 November 2014 pp 1623-1627 Rapid Communications. Synthesis and properties of a dual responsive hydrogel by inverse microemulsion polymerization · Tao Wan Min Xu Liyi Chen ...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences. Shivanand M Pudakalakatti. Articles written in Journal of Chemical Sciences. Volume 127 Issue 6 June 2015 pp 1091-1097 Regular Articles. Simultaneous acquisition of three NMR spectra in a single experiment for rapid resonance assignments in metabolomics · Shivanand ...

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences. Min Xu. Articles written in Journal of Chemical Sciences. Volume 126 Issue 6 November 2014 pp 1623-1627 Rapid Communications. Synthesis and properties of a dual responsive hydrogel by inverse microemulsion polymerization · Tao Wan Min Xu Liyi Chen Daqing Wu ...

RAPIDLY DECAYING SUPERNOVA 2010X: A CANDIDATE '.Ia' EXPLOSION

International Nuclear Information System (INIS)

Kasliwal, Mansi M.; Kulkarni, S. R.; Quimby, Robert M.; Ofek, Eran O.; Gal-Yam, Avishay; Yaron, Ofer; Sternberg, Assaf; Arcavi, Iair; Nugent, Peter; Poznanski, Dovi; Jacobsen, Janet; Howell, D. Andrew; Sullivan, Mark; Rich, Douglas J.; Burke, Paul F.; Brimacombe, Joseph; Milisavljevic, Dan; Fesen, Robert; Bildsten, Lars; Shen, Ken

2010-01-01

We present the discovery, photometric, and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with τ d = 5 days and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M r = -17 mag and has mean velocities of 10,000 km s -1 . Our light curve modeling suggests a radioactivity-powered event and an ejecta mass of 0.16 M sun . If powered by Nickel, we show that the Nickel mass must be very small (∼0.02 M sun ) and that the supernova quickly becomes optically thin to γ-rays. Our spectral modeling suggests that SN 2010X and SN 2002bj have similar chemical compositions and that one of aluminum or helium is present. If aluminum is present, we speculate that this may be an accretion-induced collapse of an O-Ne-Mg white dwarf. If helium is present, all observables of SN 2010X are consistent with being a thermonuclear helium shell detonation on a white dwarf, a '.Ia' explosion. With the 1 day dynamic-cadence experiment on the Palomar Transient Factory, we expect to annually discover a few such events.

Clear as Crystal: The Story of the Braggs--How X-Ray Crystallography Has Contributed to Science

Science.gov (United States)

George, Robert; Patterson, John

2014-01-01

Here is a brief history of the work of two of Australia's most famous scientists, Sir William Bragg and his son Sir Lawrence Bragg. Jointly awarded the Nobel Prize in 1915 for their groundbreaking research into the use of X-rays to study the chemical structure and function of molecules, they have contributed to our heritage and to science at an…

On qualitative analysis of delay systems and x = f(t,x,xσ ) x = f(t,x,xσ ...

Indian Academy of Sciences (India)

The theory of dynamical systems on time scales has been developing rapidly and has received a ... Open intervals and half-open intervals are defined accordingly. ... h. , h = 0, z, h = 0, where Log is the principal logarithm function. 3. Delay systems. In this section we consider following delay systems x. △ = f(t,xt), t ∈ [a, b]. ∗.

X-ray Diffraction Results from Mars Science Laboratory: Mineralogy of Rocknest at Gale Crater

Science.gov (United States)

Bish, D. L.; Blake, D. F.; Vaniman, D. T.; Chipera, S. J.; Morris, R. V.; Ming, D. W.; Treiman, A. H.; Sarrazin, P.; Morrison, S. M.; Downs, R. T.; Achilles, C. N.; Yen, A. S.; Bristow, T. F.; Crisp, J. A.; Morookian, J. M.; Farmer, J. D.; Rampe, E. B.; Stolper, E. M.; Spanovich, N.; Achilles, Cherie; Agard, Christophe; Verdasca, José Alexandre Alves; Anderson, Robert; Anderson, Ryan; Archer, Doug; Armiens-Aparicio, Carlos; Arvidson, Ray; Atlaskin, Evgeny; Atreya, Sushil; Aubrey, Andrew; Baker, Burt; Baker, Michael; Balic-Zunic, Tonci; Baratoux, David; Baroukh, Julien; Barraclough, Bruce; Bean, Keri; Beegle, Luther; Behar, Alberto; Bell, James; Bender, Steve; Benna, Mehdi; Bentz, Jennifer; Berger, Gilles; Berger, Jeff; Berman, Daniel; Bish, David; Blake, David F.; Avalos, Juan J. Blanco; Blaney, Diana; Blank, Jen; Blau, Hannah; Bleacher, Lora; Boehm, Eckart; Botta, Oliver; Böttcher, Stephan; Boucher, Thomas; Bower, Hannah; Boyd, Nick; Boynton, Bill; Breves, Elly; Bridges, John; Bridges, Nathan; Brinckerhoff, William; Brinza, David; Bristow, Thomas; Brunet, Claude; Brunner, Anna; Brunner, Will; Buch, Arnaud; Bullock, Mark; Burmeister, Sönke; Cabane, Michel; Calef, Fred; Cameron, James; Campbell, John "Iain"; Cantor, Bruce; Caplinger, Michael; Rodríguez, Javier Caride; Carmosino, Marco; Blázquez, Isaías Carrasco; Charpentier, Antoine; Chipera, Steve; Choi, David; Clark, Benton; Clegg, Sam; Cleghorn, Timothy; Cloutis, Ed; Cody, George; Coll, Patrice; Conrad, Pamela; Coscia, David; Cousin, Agnès; Cremers, David; Crisp, Joy; Cros, Alain; Cucinotta, Frank; d'Uston, Claude; Davis, Scott; Day, Mackenzie "Kenzie"; Juarez, Manuel de la Torre; DeFlores, Lauren; DeLapp, Dorothea; DeMarines, Julia; DesMarais, David; Dietrich, William; Dingler, Robert; Donny, Christophe; Downs, Bob; Drake, Darrell; Dromart, Gilles; Dupont, Audrey; Duston, Brian; Dworkin, Jason; Dyar, M. Darby; Edgar, Lauren; Edgett, Kenneth; Edwards, Christopher; Edwards, Laurence; Ehlmann, Bethany; Ehresmann, Bent; Eigenbrode, Jen; Elliott, Beverley; Elliott, Harvey; Ewing, Ryan; Fabre, Cécile; Fairén, Alberto; Farley, Ken; Farmer, Jack; Fassett, Caleb; Favot, Laurent; Fay, Donald; Fedosov, Fedor; Feldman, Jason; Feldman, Sabrina; Fisk, Marty; Fitzgibbon, Mike; Flesch, Greg; Floyd, Melissa; Flückiger, Lorenzo; Forni, Olivier; Fraeman, Abby; Francis, Raymond; François, Pascaline; Franz, Heather; Freissinet, Caroline; French, Katherine Louise; Frydenvang, Jens; Gaboriaud, Alain; Gailhanou, Marc; Garvin, James; Gasnault, Olivier; Geffroy, Claude; Gellert, Ralf; Genzer, Maria; Glavin, Daniel; Godber, Austin; Goesmann, Fred; Goetz, Walter; Golovin, Dmitry; Gómez, Felipe Gómez; Gómez-Elvira, Javier; Gondet, Brigitte; Gordon, Suzanne; Gorevan, Stephen; Grant, John; Griffes, Jennifer; Grinspoon, David; Grotzinger, John; Guillemot, Philippe; Guo, Jingnan; Gupta, Sanjeev; Guzewich, Scott; Haberle, Robert; Halleaux, Douglas; Hallet, Bernard; Hamilton, Vicky; Hardgrove, Craig; Harker, David; Harpold, Daniel; Harri, Ari-Matti; Harshman, Karl; Hassler, Donald; Haukka, Harri; Hayes, Alex; Herkenhoff, Ken; Herrera, Paul; Hettrich, Sebastian; Heydari, Ezat; Hipkin, Victoria; Hoehler, Tori; Hollingsworth, Jeff; Hudgins, Judy; Huntress, Wesley; Hurowitz, Joel; Hviid, Stubbe; Iagnemma, Karl; Indyk, Steve; Israël, Guy; Jackson, Ryan; Jacob, Samantha; Jakosky, Bruce; Jensen, Elsa; Jensen, Jaqueline Kløvgaard; Johnson, Jeffrey; Johnson, Micah; Johnstone, Steve; Jones, Andrea; Jones, John; Joseph, Jonathan; Jun, Insoo; Kah, Linda; Kahanpää, Henrik; Kahre, Melinda; Karpushkina, Natalya; Kasprzak, Wayne; Kauhanen, Janne; Keely, Leslie; Kemppinen, Osku; Keymeulen, Didier; Kim, Myung-Hee; Kinch, Kjartan; King, Penny; Kirkland, Laurel; Kocurek, Gary; Koefoed, Asmus; Köhler, Jan; Kortmann, Onno; Kozyrev, Alexander; Krezoski, Jill; Krysak, Daniel; Kuzmin, Ruslan; Lacour, Jean Luc; Lafaille, Vivian; Langevin, Yves; Lanza, Nina; Lasue, Jeremie; Le Mouélic, Stéphane; Lee, Ella Mae; Lee, Qiu-Mei; Lees, David; Lefavor, Matthew; Lemmon, Mark; Malvitte, Alain Lepinette; Leshin, Laurie; Léveillé, Richard; Lewin-Carpintier, Éric; Lewis, Kevin; Li, Shuai; Lipkaman, Leslie; Little, Cynthia; Litvak, Maxim; Lorigny, Eric; Lugmair, Guenter; Lundberg, Angela; Lyness, Eric; Madsen, Morten; Mahaffy, Paul; Maki, Justin; Malakhov, Alexey; Malespin, Charles; Malin, Michael; Mangold, Nicolas; Manhes, Gérard; Manning, Heidi; Marchand, Geneviève; Jiménez, Mercedes Marín; García, César Martín; Martin, Dave; Martin, Mildred; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Mauchien, Patrick; Maurice, Sylvestre; McAdam, Amy; McCartney, Elaina; McConnochie, Timothy; McCullough, Emily; McEwan, Ian; McKay, Christopher; McLennan, Scott; McNair, Sean; Melikechi, Noureddine; Meslin, Pierre-Yves; Meyer, Michael; Mezzacappa, Alissa; Miller, Hayden; Miller, Kristen; Milliken, Ralph; Ming, Douglas; Minitti, Michelle; Mischna, Michael; Mitrofanov, Igor; Moersch, Jeff; Mokrousov, Maxim; Jurado, Antonio Molina; Moores, John; Mora-Sotomayor, Luis; Morookian, John Michael; Morris, Richard; Morrison, Shaunna; Mueller-Mellin, Reinhold; Muller, Jan-Peter; Caro, Guillermo Muñoz; Nachon, Marion; López, Sara Navarro; Navarro-González, Rafael; Nealson, Kenneth; Nefian, Ara; Nelson, Tony; Newcombe, Megan; Newman, Claire; Newsom, Horton; Nikiforov, Sergey; Niles, Paul; Nixon, Brian; Dobrea, Eldar Noe; Nolan, Thomas; Oehler, Dorothy; Ollila, Ann; Olson, Timothy; Owen, Tobias; Hernández, Miguel Ángel de Pablo; Paillet, Alexis; Pallier, Etienne; Palucis, Marisa; Parker, Timothy; Parot, Yann; Patel, Kiran; Paton, Mark; Paulsen, Gale; Pavlov, Alex; Pavri, Betina; Peinado-González, Verónica; Pepin, Robert; Peret, Laurent; Perez, Rene; Perrett, Glynis; Peterson, Joe; Pilorget, Cedric; Pinet, Patrick; Pla-García, Jorge; Plante, Ianik; Poitrasson, Franck; Polkko, Jouni; Popa, Radu; Posiolova, Liliya; Posner, Arik; Pradler, Irina; Prats, Benito; Prokhorov, Vasily; Purdy, Sharon Wilson; Raaen, Eric; Radziemski, Leon; Rafkin, Scot; Ramos, Miguel; Rampe, Elizabeth; Raulin, François; Ravine, Michael; Reitz, Günther; Rennó, Nilton; Rice, Melissa; Richardson, Mark; Robert, François; Robertson, Kevin; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio J.; Rowland, Scott; Rubin, David; Saccoccio, Muriel; Salamon, Andrew; Sandoval, Jennifer; Sanin, Anton; Fuentes, Sara Alejandra Sans; Saper, Lee; Sarrazin, Philippe; Sautter, Violaine; Savijärvi, Hannu; Schieber, Juergen; Schmidt, Mariek; Schmidt, Walter; Scholes, Daniel "Dan"; Schoppers, Marcel; Schröder, Susanne; Schwenzer, Susanne; Martinez, Eduardo Sebastian; Sengstacken, Aaron; Shterts, Ruslan; Siebach, Kirsten; Siili, Tero; Simmonds, Jeff; Sirven, Jean-Baptiste; Slavney, Susie; Sletten, Ronald; Smith, Michael; Sánchez, Pablo Sobrón; Spanovich, Nicole; Spray, John; Squyres, Steven; Stack, Katie; Stalport, Fabien; Steele, Andrew; Stein, Thomas; Stern, Jennifer; Stewart, Noel; Stipp, Susan Louise Svane; Stoiber, Kevin; Stolper, Ed; Sucharski, Bob; Sullivan, Rob; Summons, Roger; Sumner, Dawn; Sun, Vivian; Supulver, Kimberley; Sutter, Brad; Szopa, Cyril; Tan, Florence; Tate, Christopher; Teinturier, Samuel; ten Kate, Inge; Thomas, Peter; Thompson, Lucy; Tokar, Robert; Toplis, Mike; Redondo, Josefina Torres; Trainer, Melissa; Treiman, Allan; Tretyakov, Vladislav; Urqui-O'Callaghan, Roser; Van Beek, Jason; Van Beek, Tessa; VanBommel, Scott; Vaniman, David; Varenikov, Alexey; Vasavada, Ashwin; Vasconcelos, Paulo; Vicenzi, Edward; Vostrukhin, Andrey; Voytek, Mary; Wadhwa, Meenakshi; Ward, Jennifer; Webster, Chris; Weigle, Eddie; Wellington, Danika; Westall, Frances; Wiens, Roger Craig; Wilhelm, Mary Beth; Williams, Amy; Williams, Joshua; Williams, Rebecca; Williams, Richard B. "Mouser"; Wilson, Mike; Wimmer-Schweingruber, Robert; Wolff, Mike; Wong, Mike; Wray, James; Wu, Megan; Yana, Charles; Yen, Albert; Yingst, Aileen; Zeitlin, Cary; Zimdar, Robert; Mier, María-Paz Zorzano

2013-09-01

The Mars Science Laboratory rover Curiosity scooped samples of soil from the Rocknest aeolian bedform in Gale crater. Analysis of the soil with the Chemistry and Mineralogy (CheMin) x-ray diffraction (XRD) instrument revealed plagioclase (~An57), forsteritic olivine (~Fo62), augite, and pigeonite, with minor K-feldspar, magnetite, quartz, anhydrite, hematite, and ilmenite. The minor phases are present at, or near, detection limits. The soil also contains 27 ± 14 weight percent x-ray amorphous material, likely containing multiple Fe3+- and volatile-bearing phases, including possibly a substance resembling hisingerite. The crystalline component is similar to the normative mineralogy of certain basaltic rocks from Gusev crater on Mars and of martian basaltic meteorites. The amorphous component is similar to that found on Earth in places such as soils on the Mauna Kea volcano, Hawaii.

Total reflection X-ray spectroscopy as a rapid analytical method for uranium determination in drainage water

International Nuclear Information System (INIS)

Matsuyama, Tsugufumi; Sakai, Yasuhiro; Izumoto, Yukie; Imaseki, Hitoshi; Hamano, Tsuyoshi; Yoshii, Hiroshi

2017-01-01

Uranium concentrations in drainage water are typically determined by α-spectrometry. However, due to the low specific radioactivity of uranium, the evaporation of large volumes of drainage water, followed by several hours of measurements, is required. Thus, the development of a rapid and simple detection method for uranium in drainage water would enhance the operation efficiency of radiation control workers. We herein propose a novel methodology based on total reflection X-ray fluorescence (TXRF) for the measurement of uranium in contaminated water. TXRF is a particularly desirable method for the rapid and simple evaluation of uranium in contaminated water, as chemical pretreatment of the sample solution is not necessary, measurement times are typically several seconds, and the required sample volume is low. We herein employed sample solutions containing several different concentrations of uranyl acetate with yttrium as an internal standard. The solutions were placed onto sample holders, and were dried prior to TXRF measurements. The relative intensity, otherwise defined as the net intensity ratio of the Lα peak of uranium to the Kα peak of yttrium, was directly proportional to the uranium concentration. Using this method, a TXRF detection limit for uranium in contaminated water of 0.30 μg/g was achieved. (author)

Australian synchrotron radiation science

International Nuclear Information System (INIS)

White, J.W.

1996-01-01

Full text: The Australian Synchrotron Radiation Program, ASRP, has been set up as a major national research facility to provide facilities for scientists and technologists in physics, chemistry, biology and materials science who need access to synchrotron radiation. Australia has a strong tradition in crystallography and structure determination covering small molecule crystallography, biological and protein crystallography, diffraction science and materials science and several strong groups are working in x-ray optics, soft x-ray and vacuum ultra-violet physics. A number of groups whose primary interest is in the structure and dynamics of surfaces, catalysts, polymer and surfactant science and colloid science are hoping to use scattering methods and, if experience in Europe, Japan and USA can be taken as a guide, many of these groups will need third generation synchrotron access. To provide for this growing community, the Australian National Beamline at the Photon Factory, Tsukuba, Japan, has been established since 1990 through a generous collaboration with Japanese colleagues, the beamline equipment being largely produced in Australia. This will be supplemented in 1997 with access to the world's most powerful synchrotron x-ray source at the Advanced Photon Source, Argonne National Laboratory, USA. Some recent experiments in surface science using neutrons as well as x-rays from the Australian National Beamline will be used to illustrate one of the challenges that synchrotron x-rays may meet

Inequalities in Science

OpenAIRE

Xie, Y.

2014-01-01

Inequalities in scientists’ contributions to science and their rewards have always been very high. There are good reasons to propose that inequalities in science across research institutions and across individual scientists have increased in recent years. In the meantime, however, globalization and internet technology have narrowed inequalities in science across nations and facilitated the expansion of science and rapid production of scientific discoveries through international collaborative ...

Soft X-Ray Microscopy and Spectroscopy at the Molecular Environmental Science Beamline at the Advanced Light Source

Energy Technology Data Exchange (ETDEWEB)

Bluhm, Hendrik; Andersson, Klas J.; Araki, Tohru; Benzerara, Karim; Brown, Gordon E.; Dynes, Jay J.; Ghosal, Sutapa; Gilles, Mary K.; Hansen, Hans C.; Hemminger, J. C.; Hitchcock, Adam P.; Ketteler, Guido; Kilcoyne, Arthur L.; Kneedler, Eric M.; Lawrence, John R.; Leppard, Gary G.; Majzlam, Juraj; Mun, B. S.; Myneni, Satish C.; Nilsson, Anders R.; Ogasawara, Hirohito; Ogletree, D. F.; Pecher, Klaus H.; Salmeron, Miquel B.; Shuh, David K.; Tonner, Brian; Tyliszczak, Tolek; Warwick, Tony; Yoon, T. H.

2006-02-01

We present examples of the application of synchrotron-based spectroscopies and microscopies to environmentally-relevant samples. The experiments were performed at the Molecular Environmental Science beamline (11.0.2) at the Advanced Light Source, Lawrence Berkeley National Laboratory. Examples range from the study of water monolayers on Pt(111) single crystal surfaces using X-ray emission spectroscopy and the examination of alkali halide solution/water vapor interfaces using ambient pressure photoemission spectroscopy, to the investigation of actinides, river-water biofilms, Al-containing colloids and mineral-bacteria suspensions using scanning transmission X-ray spectromicroscopy. The results of our experiments show that spectroscopy and microscopy in the soft X-ray energy range are excellent tools for the investigation of environmentally relevant samples under realistic conditions, i.e. with water or water vapor present at ambient temperature.

Ultra-short wavelength x-ray system

Science.gov (United States)

Umstadter, Donald [Ann Arbor, MI; He, Fei [Ann Arbor, MI; Lau, Yue-Ying [Potomac, MD

2008-01-22

A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

Development of a Rapid Detection Method for Potato virus X by Reverse Transcription Loop-Mediated Isothermal Amplification

Directory of Open Access Journals (Sweden)

Joojin Jeong

2015-09-01

Full Text Available The primary step for efficient control of viral diseases is the development of simple, rapid, and sensitive virus detection. Reverse transcription loop-mediated isothermal amplification (RT-LAMP has been used to detect viral RNA molecules because of its simplicity and high sensitivity for a number of viruses. RT-LAMP for the detection of Potato virus X (PVX was developed and compared with conventional reverse transcription polymerase chain reaction (RT-PCR to demonstrate its advantages over RT-PCR. RT-LAMP reactions were conducted with or without a set of loop primers since one out of six primers showed PVX specificity. Based on real-time monitoring, RT-LAMP detected PVX around 30 min, compared to 120 min for RT-PCR. By adding a fluorescent reagent during the reaction, the extra step of visualization by gel electrophoresis was not necessary. RT-LAMP was conducted using simple inexpensive instruments and a regular incubator to evaluate whether RNA could be amplified at a constant temperature instead of using an expensive thermal cycler. This study shows the potential of RT-LAMP for the diagnosis of viral diseases and PVX epidemiology because of its simplicity and rapidness compared to RT-PCR.

Time-averaged discharge rate of subaerial lava at Kīlauea Volcano, Hawai‘i, measured from TanDEM-X interferometry: Implications for magma supply and storage during 2011-2013

Science.gov (United States)

Poland, Michael P.

2014-01-01

Differencing digital elevation models (DEMs) derived from TerraSAR add-on for Digital Elevation Measurements (TanDEM-X) synthetic aperture radar imagery provides a measurement of elevation change over time. On the East Rift Zone (EZR) of Kīlauea Volcano, Hawai‘i, the effusion of lava causes changes in topography. When these elevation changes are summed over the area of an active lava flow, it is possible to quantify the volume of lava emplaced at the surface during the time spanned by the TanDEM-X data—a parameter that can be difficult to measure across the entirety of an ~100 km2 lava flow field using ground-based techniques or optical remote sensing data. Based on the differences between multiple TanDEM-X-derived DEMs collected days to weeks apart, the mean dense-rock equivalent time-averaged discharge rate of lava at Kīlauea between mid-2011 and mid-2013 was approximately 2 m3/s, which is about half the long-term average rate over the course of Kīlauea's 1983–present ERZ eruption. This result implies that there was an increase in the proportion of lava stored versus erupted, a decrease in the rate of magma supply to the volcano, or some combination of both during this time period. In addition to constraining the time-averaged discharge rate of lava and the rates of magma supply and storage, topographic change maps derived from space-based TanDEM-X data provide insights into the four-dimensional evolution of Kīlauea's ERZ lava flow field. TanDEM-X data are a valuable complement to other space-, air-, and ground-based observations of eruptive activity at Kīlauea and offer great promise at locations around the world for aiding with monitoring not just volcanic eruptions but any hazardous activity that results in surface change, including landslides, floods, earthquakes, and other natural and anthropogenic processes.

NICER observations of MAXI J1820+070 suggest a rapidly-brightening black hole X-ray binary in the hard state

Science.gov (United States)

Uttley, P.; Gendreau, K.; Markwardt, C.; Strohmayer, T. E.; Bult, P.; Arzoumanian, Z.; Pottschmidt, K.; Ray, P. S.; Remillard, R.; Pasham, D.; Steiner, J.; Neilsen, J.; Homan, J.; Miller, J. M.; Iwakiri, W.; Fabian, A. C.

2018-03-01

NICER observed the new X-ray transient MAXI J1820+070 (ATel #11399, #11400, #11403, #11404, #11406, #11418, #11420, #11421) on multiple occasions from 2018 March 12 to 14. & nbsp;During this time the source brightened rapidly, from a total NICER mean count rate of 880 count/s on March 12 to 2800 count/s by March 14 17:00 & nbsp;UTC, corresponding to a change in 2-10 keV modelled flux (see below) from 1.9E-9 to 5E-9 erg cm-2 s-1. & nbsp; The broadband X-ray spectrum is absorbed by a low column density (fitting the model given below, we obtain 1.5E21 cm-2), in keeping with the low Galactic column in the direction of the source (ATel #11418; Dickey & Lockman, 1990, ARAA, 28, 215; Kalberla et al. 2005, A &A, 440, 775) and consists of a hard power-law component with weak reflection features (broad iron line and narrow 6.4 keV line core) and an additional soft X-ray component.

Rapid Chemometric X-Ray Fluorescence approaches for spectral Diagnostics of Cancer utilizing Tissue Trace Metals and Speciation profiles

International Nuclear Information System (INIS)

Okonda, J.J.

2015-01-01

Energy dispersive X-ray fluorescence (EDXRF) spectroscopy is an analytical method for identification and quantification of elements in materials by measurement of their spectral energy and intensity. EDXRFS spectroscopic technique involves simultaneous non-invasive acquisition of both fluorescence and scatter spectra from samples for quantitative determination of trace elemental content in complex matrix materials. The objective is develop a chemometric-aided EDXRFS method for rapid diagnosis of cancer and its severity (staging) based on analysis of trace elements (Cu, Zn, Fe, Se and Mn), their speciation and multivariate alterations of the elements in cancerous body tissue samples as cancer biomarkers. The quest for early diagnosis of cancer is based on the fact that early intervention translates to higher survival rate and better quality of life. Chemometric aided EDXRFS cancer diagnostic model has been evaluated as a direct and rapid superior alternative for the traditional quantitative methods used in XRF such as FP method. PCA results of cultured samples indicate that it is possible to characterize cancer at early and late stage of development based on trace elemental profiles

Introducing the ARL X'Tra x-ray diffraction system

International Nuclear Information System (INIS)

Harris, L.

2002-01-01

Full text: The ARL X'Tra is a state-of-the-art solution for powder X-ray diffraction in a large range of applications such as pharmaceuticals and biosciences, chemicals, earth sciences, semi-conductors, metallurgy and ceramics. The X'Tra offers the latest technology in key diffraction components to produce a high performance instrument at an affordable price. This presentation examines some of the hardware and performance features of this instrument. Copyright (2002) Australian X-ray Analytical Association Inc

The X-ray Integral Field Unit (X-IFU) for Athena

Science.gov (United States)

Ravera, Laurent; Barret, Didier; Willem den Herder, Jan; Piro, Luigi; Cledassou, Rodolphe; Pointecouteau, Etienne; Peille, Philippe; Pajot, Francois; Arnaud, Monique; Pigot, Claude;

Bright X-ray source from a laser-driven micro-plasma-waveguide

CERN Document Server

Yi, Longqing

2016-01-01

Bright tunable x-ray sources have a number of applications in basic science, medicine and industry. The most powerful sources are synchrotrons, where relativistic electrons are circling in giant storage rings. In parallel, compact laser-plasma x-ray sources are being developed. Owing to the rapid progress in laser technology, very high-contrast femtosecond laser pulses of relativistic intensities become available. These pulses allow for interaction with micro-structured solid-density plasma without destroying the structure by parasitic pre-pulses. The high-contrast laser pulses as well as the manufacturing of materials at micro- and nano-scales open a new realm of possibilities for laser interaction with photonic materials at the relativistic intensities. Here we demonstrate, via numerical simulations, that when coupling with a readily available 1.8 Joule laser, a micro-plasma-waveguide (MPW) may serve as a novel compact x-ray source. Electrons are extracted from the walls by the laser field and form a dense ...

Automatic X-ray television rig for high-speed radiography of polycrystals

International Nuclear Information System (INIS)

Bezbakh, V.D.; Garasim, Yu.A.; Oshkaderov, S.P.; Pet'kov, V.V.

1993-01-01

The high-speed radiography method is used for studying the phase and structural transformation in metals and alloys during rapid changes in temperature. In order to improve the effectiveness of this method the Institute of Metal Physics, Ukrainian Academy of Sciences, has developed an automatic rig for high-speed radiography of polycrystalline materials using a television method for recording the x-ray diffraction patterns. The rig, described here, consists of an x-ray block, a vacuum chamber, a device for programmed electro-contact heating of specimens, a system for imaging and scanning x-ray diffraction patterns, and a system for collecting and analyzing the data. Focusing is carried out by the Zeeman-Bolin method. The new rig helps to significantly reduce the recording time and ensures adequate quality and reliability of the recorded diffraction image over a wide range of temperatures. Data using the rig is presented for high-speed radiography for cooling a specimen of G20 steel. 4 refs., 4 figs

Simbol-X Core Science in a Context

Science.gov (United States)

Fiore, F.; Arnaud, M.; Briel, U.; Cavazzuti, E.; Cledassou, R.; Counil, J. L.; Comastri, A.; Ferrando, P.; Giommi, P.; Goldwurm, A.; Lamarle, O.; Lanzuisi, G.; Laurent, P.; Lebrun, F.; Malaguti, G.; Mereghetti, S.; Micela, G.; Pareschi, G.; Piconcelli, E.; Piermaria, M.; Puccetti, S.; Roques, J.-P.; Tagliaferri, G.; Vignali, C.

2009-05-01

Taking advantage of emerging technology in mirror manufacturing and spacecraft formation flying, Simbol-X will push grazing incidence imaging up to ~80 keV, providing an improvement of roughly three orders of magnitude in sensitivity and angular resolution compared to all instruments that have operated so far above 10 keV. This will open a new window in X-ray astronomy, allowing breakthrough studies on black hole physics and census and particle acceleration mechanisms. We discuss here synergies between Simbol-X and the main multiwavelength facilities that will operate in the next decade, and present a quantitative comparison between Simbol-X and its main competitors, NuStar and Astro-H.

Simbol-X Core Science in a Context

International Nuclear Information System (INIS)

Fiore, F.; Lanzuisi, G.; Piconcelli, E.; Arnaud, M.; Briel, U.; Cavazzuti, E.; Giommi, P.; Piermaria, M.; Puccetti, S.; Cledassou, R.; Counil, J. L.; Lamarle, O.; Comastri, A.; Ferrando, P.; Goldwurm, A.; Laurent, P.; Lebrun, F.; Malaguti, G.; Mereghetti, S.; Micela, G.

2009-01-01

Taking advantage of emerging technology in mirror manufacturing and spacecraft formation flying, Simbol-X will push grazing incidence imaging up to ∼80 keV, providing an improvement of roughly three orders of magnitude in sensitivity and angular resolution compared to all instruments that have operated so far above 10 keV. This will open a new window in X-ray astronomy, allowing breakthrough studies on black hole physics and census and particle acceleration mechanisms. We discuss here synergies between Simbol-X and the main multiwavelength facilities that will operate in the next decade, and present a quantitative comparison between Simbol-X and its main competitors, NuStar and Astro-H.

Inequalities in Science

Science.gov (United States)

Xie, Y.

2014-01-01

Inequalities in scientists’ contributions to science and their rewards have always been very high. There are good reasons to propose that inequalities in science across research institutions and across individual scientists have increased in recent years. In the meantime, however, globalization and internet technology have narrowed inequalities in science across nations and facilitated the expansion of science and rapid production of scientific discoveries through international collaborative networks. PMID:24855244

A JEM-X catalog of X-ray sources

DEFF Research Database (Denmark)

Westergaard, Niels Jørgen Stenfeldt; Chenevez, Jerome; Lund, Niels

2007-01-01

The JEM-X catalog of X-ray sources presented here is based on detections in individual science windows with a sensitivity limit of about 10 mCrab (5-15 keV). It contains 127 sources and only those that can be identified from the existing reference catalog. The input data are taken from the, up...

A rapid alternative to X-ray crystallography for chiral determination: case studies of vibrational circular dichroism (VCD) to advance drug discovery projects.

Science.gov (United States)

Wesolowski, Steven S; Pivonka, Don E

2013-07-15

The absolute stereochemistry of chiral drugs is usually established via X-ray crystallography. However, vibrational circular dichroism (VCD) spectroscopy coupled with quantum mechanics simulations offers a rapid alternative to crystallography and is readily applied to both crystalline and non-crystalline samples. VCD is an effective complement to X-ray analysis of drug candidates, and it can be used as a high-throughput means of assessing absolute stereochemistry at all phases of the discovery process (hundreds of assignments per year). The practical implementation (or fee-for-service outsourcing) of VCD and selected case studies are illustrated with an emphasis on providing utility and impact to pharmaceutical discovery programs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Earth System Science. K D Singh. Articles written in Journal of Earth System Science. Volume 122 Issue 1 February 2013 pp 93-106. A field technique for rapid lithological discrimination and ore mineral identification: Results from Mamandur Polymetal Deposit, India · D Ramakrishnan M Nithya ...

Rapid phenotyping of crop root systems in undisturbed field soils using X-ray computed tomography.

Science.gov (United States)

Pfeifer, Johannes; Kirchgessner, Norbert; Colombi, Tino; Walter, Achim

2015-01-01

X-ray computed tomography (CT) has become a powerful tool for root phenotyping. Compared to rather classical, destructive methods, CT encompasses various advantages. In pot experiments the growth and development of the same individual root can be followed over time and in addition the unaltered configuration of the 3D root system architecture (RSA) interacting with a real field soil matrix can be studied. Yet, the throughput, which is essential for a more widespread application of CT for basic research or breeding programs, suffers from the bottleneck of rapid and standardized segmentation methods to extract root structures. Using available methods, root segmentation is done to a large extent manually, as it requires a lot of interactive parameter optimization and interpretation and therefore needs a lot of time. Based on commercially available software, this paper presents a protocol that is faster, more standardized and more versatile compared to existing segmentation methods, particularly if used to analyse field samples collected in situ. To the knowledge of the authors this is the first study approaching to develop a comprehensive segmentation method suitable for comparatively large columns sampled in situ which contain complex, not necessarily connected root systems from multiple plants grown in undisturbed field soil. Root systems from several crops were sampled in situ and CT-volumes determined with the presented method were compared to root dry matter of washed root samples. A highly significant (P < 0.01) and strong correlation (R(2) = 0.84) was found, demonstrating the value of the presented method in the context of field research. Subsequent to segmentation, a method for the measurement of root thickness distribution has been used. Root thickness is a central RSA trait for various physiological research questions such as root growth in compacted soil or under oxygen deficient soil conditions, but hardly assessable in high throughput until today, due

Multielemental X-ray radiometric analysis of ferromanganese concretions

International Nuclear Information System (INIS)

Metelev, A.Yu.; Grigor'ev, A.I.; Rakita, K.A.; Mamaenko, M.V.; Ivanenko, V.V.

1994-01-01

Ferromanganese concretions are promising mineral resources of the ocean. Most often, they are analyzed by atomic-absorption, spectra, X-ray spectral, neutron-activation, and X-ray radiometric methods. Note that X-ray radiometric analysis (XRRA) allows the sufficiently rapid determination of a great number of elements in ferromanganese concretions. The possibility of using XRRA with saturated and thin layers was shown; however, the data on the precision and accuracy of the technique was not given. The purpose of this study is to evaluate the basic performance characteristics of the multielemental X-ray radiometric analysis of ferromanganese concretions (Pacific Ocean). Determinations for K,Ca and Ti content were made using a 55 Fe source and for Mn, Fe, Ni, Cu, Zn, Pb, Sr, Y, Zr, Nb, and Mo contents by using a 109 Cd source. The precision and accuracy of the method was investigated by using reference concretions; it was found the confidence intervals overlap for all of the elements except Ca and Pb. The relative standard deviation was 1-5%, indicating the high precision of the method. The described technique is successfully used on research vessels of the Far East Division of the Russian Academy of Sciences and in South Pacific Ocean geological expeditions of PO open-quotes Dal'morgeologiyaclose quotes

Rapid methods for multi-elemental X-ray fluorescence analysis using excitation isotope sources and Si(Li)-semiconductor detector

International Nuclear Information System (INIS)

Zhuravleva, E.L.

1980-01-01

Some rapid methods using an unique calibration curve have been developed for multi-elemental X-ray fluorescence analysis of thin and thick layers of various samples having low contents of heavy elements. The matrix absorption effect in thick samples is taken into account according to the scattered radiation.The similar method using a unique calibration curve for determination of low contents of trace elements in thin layers without account of matrix effect is proposed. The results on the intercomposition run soil-5 are in good agreement with the data obtained in different laboratories. The errors of the method are 10 %; in a case of peak superposition - 15 %

Applications for X-ray detectors in astrophysics

International Nuclear Information System (INIS)

Remillard, R.A.

2003-01-01

Full text: Position-sensitive X-Ray detectors continue to playa central role in high-energy astrophysics. The current science goals are reviewed with emphasis on requirements in terms of camera performance. Wide-field imaging techniques, including coded mask cameras, are an essential part of space programs because of the transient nature of high-priority targets, e.g. eruptions from black-hole binaries and cosmic explosions such as gamma ray bursts. Pointing X-ray telescopes are being planned with a wide range of photon energies and with collection designs that include both mirrors and coded masks. Requirements for high spectral resolution and high time resolution are driven by diverse types of X-ray sources such as msec pulsars, quasars with emission-line profiles shaped by general relativity, and X-ray binaries that exhibit quasi-periodic oscillations in the range of 40-1300 Hz. Many laboratories and universities are involved in space-qualification of new detector technologies, e.g. CZT cameras, X-ray calorimeters, new types of CCDs, and GEM detectors. Even X-ray interferometry is on the horizon of NASA's science roadmap. The difficulties in advancing new technologies for space science applications require careful coordinations between industry and science groups in order to solve science problems while minimizing risk

Direct rapid analysis of trace bioavailable soil macronutrients by chemometrics-assisted energy dispersive X-ray fluorescence and scattering spectrometry.

Science.gov (United States)

Kaniu, M I; Angeyo, K H; Mwala, A K; Mangala, M J

2012-06-04

Precision agriculture depends on the knowledge and management of soil quality (SQ), which calls for affordable, simple and rapid but accurate analysis of bioavailable soil nutrients. Conventional SQ analysis methods are tedious and expensive. We demonstrate the utility of a new chemometrics-assisted energy dispersive X-ray fluorescence and scattering (EDXRFS) spectroscopy method we have developed for direct rapid analysis of trace 'bioavailable' macronutrients (i.e. C, N, Na, Mg, P) in soils. The method exploits, in addition to X-ray fluorescence, the scatter peaks detected from soil pellets to develop a model for SQ analysis. Spectra were acquired from soil samples held in a Teflon holder analyzed using (109)Cd isotope source EDXRF spectrometer for 200 s. Chemometric techniques namely principal component analysis (PCA), partial least squares (PLS) and artificial neural networks (ANNs) were utilized for pattern recognition based on fluorescence and Compton scatter peaks regions, and to develop multivariate quantitative calibration models based on Compton scatter peak respectively. SQ analyses were realized with high CMD (R(2)>0.9) and low SEP (0.01% for N and Na, 0.05% for C, 0.08% for Mg and 1.98 μg g(-1) for P). Comparison of predicted macronutrients with reference standards using a one-way ANOVA test showed no statistical difference at 95% confidence level. To the best of the authors' knowledge, this is the first time that an XRF method has demonstrated utility in trace analysis of macronutrients in soil or related matrices. Copyright © 2012 Elsevier B.V. All rights reserved.

Ultrafast Science Opportunities with Electron Microscopy

Energy Technology Data Exchange (ETDEWEB)

DURR, HERMANN; Wang, X.J., ed.

2016-04-28

X-rays and electrons are two of the most fundamental probes of matter. When the Linac Coherent Light Source (LCLS), the world’s first x-ray free electron laser, began operation in 2009, it transformed ultrafast science with the ability to generate laser-like x-ray pulses from the manipulation of relativistic electron beams. This document describes a similar future transformation. In Transmission Electron Microscopy, ultrafast relativistic (MeV energy) electron pulses can achieve unsurpassed spatial and temporal resolution. Ultrafast temporal resolution will be the next frontier in electron microscopy and can ideally complement ultrafast x-ray science done with free electron lasers. This document describes the Grand Challenge science opportunities in chemistry, material science, physics and biology that arise from an MeV ultrafast electron diffraction & microscopy facility, especially when coupled with linac-based intense THz and X-ray pump capabilities.

New opportunities for 3D materials science of polycrystalline materials at the micrometre lengthscale by combined use of X-ray diffraction and X-ray imaging

Energy Technology Data Exchange (ETDEWEB)

Ludwig, W., E-mail: ludwig@esrf.fr [Universite de Lyon, INSA-Lyon, MATEIS CNRS UMR 5510, 69621Villeurbanne (France); European Synchrotron Radiation Facility, BP220, 38043 Grenoble (France); King, A. [European Synchrotron Radiation Facility, BP220, 38043 Grenoble (France); School of Materials, University of Manchester, Manchester, M13 9PL (United Kingdom); Reischig, P. [European Synchrotron Radiation Facility, BP220, 38043 Grenoble (France); Herbig, M. [Universite de Lyon, INSA-Lyon, MATEIS CNRS UMR 5510, 69621Villeurbanne (France); Lauridsen, E.M.; Schmidt, S. [Riso National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, DK-4000 Roskilde (Denmark); Proudhon, H.; Forest, S. [MINES ParisTech, Centre des materiaux, CNRS UMR 7633, BP 87, 91003 Evry Cedex (France); Cloetens, P.; Roscoat, S. Rolland du [European Synchrotron Radiation Facility, BP220, 38043 Grenoble (France); Buffiere, J.Y. [Universite de Lyon, INSA-Lyon, MATEIS CNRS UMR 5510, 69621Villeurbanne (France); Marrow, T.J. [School of Materials, University of Manchester, Manchester, M13 9PL (United Kingdom); Poulsen, H.F. [Riso National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, DK-4000 Roskilde (Denmark)

2009-10-25

Non-destructive, three-dimensional (3D) characterization of the grain structure in mono-phase polycrystalline materials is an open challenge in material science. Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting possibilities for mapping 3D grain shapes and crystallographic orientations for certain categories of polycrystalline materials. Direct visualisation of the three-dimensional grain boundary network or of two-phase (duplex) grain structures by means of absorption and/or phase contrast techniques may be possible, but is restricted to specific material systems. A recent extension of this methodology, termed X-ray diffraction contrast tomography (DCT), combines the principles of X-ray diffraction imaging, three-dimensional X-ray diffraction microscopy (3DXRD) and image reconstruction from projections. DCT provides simultaneous access to 3D grain shape, crystallographic orientation and local attenuation coefficient distribution. The technique applies to the larger range of plastically undeformed, polycrystalline mono-phase materials, provided some conditions on grain size and texture are fulfilled. The straightforward combination with high-resolution microtomography opens interesting new possibilities for the observation of microstructure related damage and deformation mechanisms in these materials.

New opportunities for 3D materials science of polycrystalline materials at the micrometre lengthscale by combined use of X-ray diffraction and X-ray imaging

International Nuclear Information System (INIS)

Ludwig, W.; King, A.; Reischig, P.; Herbig, M.; Lauridsen, E.M.; Schmidt, S.; Proudhon, H.; Forest, S.; Cloetens, P.; Roscoat, S. Rolland du; Buffiere, J.Y.; Marrow, T.J.; Poulsen, H.F.

2009-01-01

Non-destructive, three-dimensional (3D) characterization of the grain structure in mono-phase polycrystalline materials is an open challenge in material science. Recent advances in synchrotron based X-ray imaging and diffraction techniques offer interesting possibilities for mapping 3D grain shapes and crystallographic orientations for certain categories of polycrystalline materials. Direct visualisation of the three-dimensional grain boundary network or of two-phase (duplex) grain structures by means of absorption and/or phase contrast techniques may be possible, but is restricted to specific material systems. A recent extension of this methodology, termed X-ray diffraction contrast tomography (DCT), combines the principles of X-ray diffraction imaging, three-dimensional X-ray diffraction microscopy (3DXRD) and image reconstruction from projections. DCT provides simultaneous access to 3D grain shape, crystallographic orientation and local attenuation coefficient distribution. The technique applies to the larger range of plastically undeformed, polycrystalline mono-phase materials, provided some conditions on grain size and texture are fulfilled. The straightforward combination with high-resolution microtomography opens interesting new possibilities for the observation of microstructure related damage and deformation mechanisms in these materials.

Emphasizing Morals, Values, Ethics, and Character Education in Science Education and Science Teaching

Science.gov (United States)

Chowdhury, Mohammad

2016-01-01

This article presents the rationale and arguments for the presence of morals, values, ethics and character education in science curriculum and science teaching. The author examines how rapid science and technological advancements and globalization are contributing to the complexities of social life and underpinning the importance of morals, values…

DSMS GENERATION FROM COSMO-SKYMED, RADARSAT-2 AND TERRASAR-X IMAGERY ON BEAUPORT (CANADA TEST SITE: EVALUATION AND COMPARISON OF DIFFERENT RADARGRAMMETRIC APPROACHES

Directory of Open Access Journals (Sweden)

P. Capaldo

2013-04-01

Full Text Available This work is focused on the analysis of potentialities of the radargrammetric DSMs generation using high resolution SAR imagery acquired by three different platforms (COSMO-SkyMed, TerraSAR-X and Radarsat-2 with particular attention to geometric orientation models. Two orientation models have been tested in this work: the rigorous Toutin’s model, developed at the Canada Center for Remote Sensing (CCRS and implemented in the commercial software package PCI Geomatica, and the radargrammetric model developed at University of Rome La Sapienza and implemented in the scientific software SISAR. A full comparison and analysis has been carried out over Beauport test site (Quebec, Canada, where a LIDAR ground truth and a dense set of GNSS CPs (Check points are available. Moreover, a preliminary comparison between the DSMs extracted, respectively with SISAR and PCI-Geomatica has been performed. The accuracy of the generated DSMs has been evaluated through the scientific software DEMANAL developed by Prof. K. Jacobsen of University of Hannover. As regards orientation models, the results shown that the Toutin’s model accuracy is slightly better than the SISAR one, even if it is important to underline that the SISAR model is computed without using a priori ground truth information. As concern DSMs assessment, the global DSMs accuracy in term of RMSE is around 4 meter and the two radargrammetric approaches show similar performances.

Degeneration of rapid eye movement sleep circuitry underlies rapid eye movement sleep behavior disorder.

Science.gov (United States)

McKenna, Dillon; Peever, John

2017-05-01

During healthy rapid eye movement sleep, skeletal muscles are actively forced into a state of motor paralysis. However, in rapid eye movement sleep behavior disorder-a relatively common neurological disorder-this natural process is lost. A lack of motor paralysis (atonia) in rapid eye movement sleep behavior disorder allows individuals to actively move, which at times can be excessive and violent. At first glance this may sound harmless, but it is not because rapid eye movement sleep behavior disorder patients frequently injure themselves or the person they sleep with. It is hypothesized that the degeneration or dysfunction of the brain stem circuits that control rapid eye movement sleep paralysis is an underlying cause of rapid eye movement sleep behavior disorder. The link between brain stem degeneration and rapid eye movement sleep behavior disorder stems from the fact that rapid eye movement sleep behavior disorder precedes, in the majority (∼80%) of cases, the development of synucleinopathies such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, which are known to initially cause degeneration in the caudal brain stem structures where rapid eye movement sleep circuits are located. Furthermore, basic science and clinical evidence demonstrate that lesions within the rapid eye movement sleep circuits can induce rapid eye movement sleep-specific motor deficits that are virtually identical to those observed in rapid eye movement sleep behavior disorder. This review examines the evidence that rapid eye movement sleep behavior disorder is caused by synucleinopathic neurodegeneration of the core brain stem circuits that control healthy rapid eye movement sleep and concludes that rapid eye movement sleep behavior disorder is not a separate clinical entity from synucleinopathies but, rather, it is the earliest symptom of these disorders. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and

SphinX soft X-ray spectrophotometer: Science objectives, design and performance

Science.gov (United States)

Gburek, S.; Sylwester, J.; Kowalinski, M.; Bakala, J.; Kordylewski, Z.; Podgorski, P.; Plocieniak, S.; Siarkowski, M.; Sylwester, B.; Trzebinski, W.; Kuzin, S. V.; Pertsov, A. A.; Kotov, Yu. D.; Farnik, F.; Reale, F.; Phillips, K. J. H.

2011-06-01

The goals and construction details of a new design Polish-led X-ray spectrophotometer are described. The instrument is aimed to observe emission from entire solar corona and is placed as a separate block within the Russian TESIS X- and EUV complex aboard the CORONAS-PHOTON solar orbiting observatory. SphinX uses silicon PIN diode detectors for high time resolution measurements of the solar spectra in the range 0.8-15 keV. Its spectral resolution allows for discerning more than hundred separate energy bands in this range. The instrument dynamic range extends two orders of magnitude below and above these representative for GOES. The relative and absolute accuracy of spectral measurements is expected to be better than few percent, as follows from extensive ground laboratory calibrations.

Proposed second harmonic acceleration system for the intense pulsed neutron source rapid cycling synchrotron

International Nuclear Information System (INIS)

Norem, J.; Brandeberry, F.; Rauchas, A.

1983-01-01

The Rapid Cycling Synchrotron (RCS) of the Intense Pulsed Neutron Source (IPNS) operating at Argonne National Laboratory is presently producing intensities of 2 to 2.5 x 10 12 protons per pulse (ppp) with the addition of a new ion source. This intensity is close to the space charge limit of the machine, estimated at approx.3 x 10 12 ppp, depending somewhat on the available aperture. With the present good performance in mind, accelerator improvements are being directed at: (1) increasing beam intensities for neutron science; (2) lowering acceleration losses to minimize activation; and (3) gaining better control of the beam so that losses can be made to occur when and where they can be most easily controlled. On the basis of preliminary measurements, we are now proposing a third cavity for the RF systems which would provide control of the longitudinal bunch shape during the cycle which would permit raising the effective space charge limit of the accelerator and reducing losses

From EXOSAT to the High Energy Astrophysics Science Archive (HEASARC): X-ray Astronomy Comes of Age

Science.gov (United States)

White, Nicholas E.

2012-01-01

In May 1983 the European Space Agency launched EXOSAT, its first X-ray astronomy observatory. Even though it lasted only 3 short years, this mission brought not only new capabilities that resulted in unexpected discoveries, but also a pioneering approach to operations and archiving that changed X-ray astronomy from observations led by small instrument teams, to an observatory approach open to the entire community through a guest observer program. The community use of the observatory was supported by a small dedicated team of scientists, the precursor to the data center activities created to support e.g. Chandra and XMM-Newton. The new science capabilities of EX OS AT included a 90 hr highly eccentric high earth orbit that allow unprecedented continuous coverage of sources as well as direct communication with the satellite that allowed real time decisions to respond to unexpected events through targets of opportunity. The advantages of this orbit demonstrated by EXOSAT resulted in Chandra and XMM-Newton selecting similar orbits. The three instruments on board the EXOSAT observatory were complementary, designed to give complete coverage over a wide energy band pass of 0.05-50 keY. An onboard processor could be programmed to give multiple data modes that could be optimized in response to science discoveries: These new capabilities resulted in many new discoveries including the first comprehensive study of AGN variability, new orbital periods in X-ray binaries and cataclysmic variables, new black holes, quasi-periodic oscillations from neutron stars and black holes and broad band X-ray spectroscopy. The EXOSAT team generated a well-organized database accessible worldwide over the nascent internet, allowing remote selection of data products, making samples and undertaking surveys from the data. The HEASARC was established by NASA at Goddard Space Flight Center in 1990 as the repository of NASA X-ray and Gamma-ray data. The proven EXOSAT database system became the core

Rapid, dynamic segregation of core forming melts: Results from in-situ High Pressure- High Temperature X-ray Tomography

Science.gov (United States)

Watson, H. C.; Yu, T.; Wang, Y.

2011-12-01

The timing and mechanisms of core formation in the Earth, as well as in Earth-forming planetesimals is a problem of significant importance in our understanding of the early evolution of terrestrial planets . W-Hf isotopic signatures in meteorites indicate that core formation in small pre-differentiated planetesimals was relatively rapid, and occurred over the span of a few million years. This time scale is difficult to achieve by percolative flow of the metallic phase through a silicate matrix in textural equilibrium. It has been suggested that during this active time in the early solar system, dynamic processes such as impacts may have caused significant deformation in the differentiating planetesimals, which could lead to much higher permeability of the core forming melts. Here, we have measured the change in permeability of core forming melts in a silicate matrix due to deformation. Mixtures of San Carlos olivine and FeS close to the equilibrium percolation threshold (~5 vol%FeS) were pre-synthesized to achieve an equilibrium microstructure, and then loaded into the rotational Drickamer apparatus at GSE-CARS, sector 13-BMD, at the Advanced Photon Source (Argonne National Laboratory). The samples were subsequently pressed to ~2GPa, and heated to 1100°C. Alternating cycles of rotation to collect X-ray tomography images, and twisting to deform the sample were conducted until the sample had been twisted by 1080°. Qualitative and quantitative analyses were performed on the resulting 3-dimensional x-ray tomographic images to evaluate the effect of shear deformation on permeability and migration velocity. Lattice-Boltzmann simulations were conducted, and show a marked increase in the permeability with increasing deformation, which would allow for much more rapid core formation in planetesimals.

X-ray Optics for BES Light Source Facilities

Energy Technology Data Exchange (ETDEWEB)

Mills, Dennis [Argonne National Lab. (ANL), Argonne, IL (United States); Padmore, Howard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lessner, Eliane [Dept. of Energy (DOE), Washington DC (United States). Office of Science

2013-03-27

Each new generation of synchrotron radiation sources has delivered an increase in average brightness 2 to 3 orders of magnitude over the previous generation. The next evolution toward diffraction-limited storage rings will deliver another 3 orders of magnitude increase. For ultrafast experiments, free electron lasers (FELs) deliver 10 orders of magnitude higher peak brightness than storage rings. Our ability to utilize these ultrabright sources, however, is limited by our ability to focus, monochromate, and manipulate these beams with X-ray optics. X-ray optics technology unfortunately lags behind source technology and limits our ability to maximally utilize even today’s X-ray sources. With ever more powerful X-ray sources on the horizon, a new generation of X-ray optics must be developed that will allow us to fully utilize these beams of unprecedented brightness. The increasing brightness of X-ray sources will enable a new generation of measurements that could have revolutionary impact across a broad area of science, if optical systems necessary for transporting and analyzing X-rays can be perfected. The high coherent flux will facilitate new science utilizing techniques in imaging, dynamics, and ultrahigh-resolution spectroscopy. For example, zone-plate-based hard X-ray microscopes are presently used to look deeply into materials, but today’s resolution and contrast are restricted by limitations of the current lithography used to manufacture nanodiffractive optics. The large penetration length, combined in principle with very high spatial resolution, is an ideal probe of hierarchically ordered mesoscale materials, if zone-plate focusing systems can be improved. Resonant inelastic X-ray scattering (RIXS) probes a wide range of excitations in materials, from charge-transfer processes to the very soft excitations that cause the collective phenomena in correlated electronic systems. However, although RIXS can probe high-energy excitations, the most exciting and

X-ray Optics for BES Light Source Facilities

International Nuclear Information System (INIS)

Mills, Dennis; Padmore, Howard; Lessner, Eliane

2013-01-01

Each new generation of synchrotron radiation sources has delivered an increase in average brightness 2 to 3 orders of magnitude over the previous generation. The next evolution toward diffraction-limited storage rings will deliver another 3 orders of magnitude increase. For ultrafast experiments, free electron lasers (FELs) deliver 10 orders of magnitude higher peak brightness than storage rings. Our ability to utilize these ultrabright sources, however, is limited by our ability to focus, monochromate, and manipulate these beams with X-ray optics. X-ray optics technology unfortunately lags behind source technology and limits our ability to maximally utilize even today's X-ray sources. With ever more powerful X-ray sources on the horizon, a new generation of X-ray optics must be developed that will allow us to fully utilize these beams of unprecedented brightness. The increasing brightness of X-ray sources will enable a new generation of measurements that could have revolutionary impact across a broad area of science, if optical systems necessary for transporting and analyzing X-rays can be perfected. The high coherent flux will facilitate new science utilizing techniques in imaging, dynamics, and ultrahigh-resolution spectroscopy. For example, zone-plate-based hard X-ray microscopes are presently used to look deeply into materials, but today's resolution and contrast are restricted by limitations of the current lithography used to manufacture nanodiffractive optics. The large penetration length, combined in principle with very high spatial resolution, is an ideal probe of hierarchically ordered mesoscale materials, if zone-plate focusing systems can be improved. Resonant inelastic X-ray scattering (RIXS) probes a wide range of excitations in materials, from charge-transfer processes to the very soft excitations that cause the collective phenomena in correlated electronic systems. However, although RIXS can probe high-energy excitations, the most exciting

Chemical leaching of rapidly solidified Al-Si binary alloys

International Nuclear Information System (INIS)

Yamauchi, I.; Takahara, K.; Tanaka, T.; Matsubara, K.

2005-01-01

Various particulate precursors of Al 100-x Si x (x = 5-12) alloys were prepared by a rapid solidification process. The rapidly solidified structures of the precursors were examined by XRD, DSC and SEM. Most of Si atoms were dissolved into the α-Al(fcc) phase by rapid solidification though the solubility of Si in the α-Al phase is negligibly small in conventional solidification. In the case of 5 at.% Si alloy, a single α-Al phase was only formed. The amount of the primary Si phase increased with increase of Si content for the alloys beyond 8 at.% Si. Rapid solidification was effective to form super-saturated α-Al precursors. These precursors were chemically leached by using a basic solution (NaOH) or a hydrochloric acid (HCl) solution. All Al atoms were removed by a HCl solution as well as a NaOH solution. Granules of the Si phase were newly formed during leaching. The specific surface area was about 50-70 m 2 /g independent of Si content. The leaching behavior in both solutions was slightly different. In the case of a NaOH solution, the shape of the precursor often degenerated after leaching. On the other hand, it was retained after leaching by a HCl solution. Fine Si particles precipitated in the α-Al phase by annealing of as-rapidly solidified precursors at 773 K for 7.2 x 10 3 s. In this case, it was difficult to obtain any products by NaOH leaching, but a few of Si particles were obtained by HCl leaching. Precipitated Si particles were dissolved by the NaOH solution. The X-ray diffraction patterns of leached specimens showed broad lines of the Si phase and its lattice constant was slightly larger than that of the pure Si phase. The microstructures of the leached specimens were examined by transmission electron microscopy. It showed that the leached specimens had a skeletal structure composed of slightly elongated particles of the Si phase and quite fine pores. The particle size was about 30-50 nm. It was of comparable order with that evaluated by Scherer

On being a scientist in a rapidly changing world.

Science.gov (United States)

Mandel, I D

1996-02-01

The practice of biological science has changed dramatically since mid-century, reshaped not only by a rapid series of landmark discoveries, but also by governmental directives, institutional policies, and public attitudes. Until 1964, the major influences were the mentor, who provided direction and indoctrination into the culture of science, and in dentistry, the newly established NIDR, which fueled the research engine with an expanding research and training program. The 1965-74 period witnessed the advent of the Institutional Review Board, an increased social involvement of biological scientists, and a recognition of the need for biological and physical safeguards in the conduct of research. The most turbulent years were 1975-89, when there was a confluence of animal rights activism and regulation, growing concerns with scientific fraud and publication malpractice, and the stresses and strains (and opportunities) resulting from the rapid expansion of the academic-industrial complex. The current period is characterized by rapid pace, high volume, and an increased depth and breadth of knowledge-a major change in scale in the conduct of science. It is an exciting time but one in which ethical issues are multiplying. Attention must be paid.

X-ray novae - what are they

International Nuclear Information System (INIS)

Wennfors, B.

1976-01-01

Ten of the two hundred cosmic X-ray sources exhibit characteristics in their emissions analogous to novae, i.e. after a rapid increase in luminosity, lasting about three days, follows a period of about a month with a slow decrease, and thereafter a rapid decrease to invisibility. The spectra of such sources are discussed in general terms and brief descriptions are given of the five which have been identified with optical objects. Three models for the history of X-ray novae, all based on X-ray emission from a compact object in an orbit very near a larger star, are discussed. (JIW)

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences. PRADEEP KUMAR BUDDE. Articles written in Journal of Chemical Sciences. Volume 130 Issue 3 March 2018 pp 27. Non-oxidative methane dehydroaromatization reaction over highly active α-MoC1−x ZSM-5 derived from pretreatment · PRADEEP KUMAR BUDDE ARVIND ...

Communication and relationship skills for rapid response teams at hamilton health sciences.

Science.gov (United States)

Cziraki, Karen; Lucas, Janie; Rogers, Toni; Page, Laura; Zimmerman, Rosanne; Hauer, Lois Ann; Daniels, Charlotte; Gregoroff, Susan

2008-01-01

Rapid response teams (RRT) are an important safety strategy in the prevention of deaths in patients who are progressively failing outside of the intensive care unit. The goal is to intervene before a critical event occurs. Effective teamwork and communication skills are frequently cited as critical success factors in the implementation of these teams. However, there is very little literature that clearly provides an education strategy for the development of these skills. Training in simulation labs offers an opportunity to assess and build on current team skills; however, this approach does not address how to meet the gaps in team communication and relationship skill management. At Hamilton Health Sciences (HHS) a two-day program was developed in collaboration with the RRT Team Leads, Organizational Effectiveness and Patient Safety Leaders. Participants reflected on their conflict management styles and considered how their personality traits may contribute to team function. Communication and relationship theories were reviewed and applied in simulated sessions in the relative safety of off-site team sessions. The overwhelming positive response to this training has been demonstrated in the incredible success of these teams from the perspective of the satisfaction surveys of the care units that call the team, and in the multi-phased team evaluation of their application to practice. These sessions offer a useful approach to the development of the soft skills required for successful RRT implementation.

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. Amarnath. Articles written in Bulletin of Materials Science. Volume 26 Issue 4 June 2003 pp 435-439 Biomaterials. Effect of heat treatments on the hydrogen embrittlement susceptibility of API X-65 grade line-pipe steel · G Ananta Nagu Amarnath T K G Namboodhiri.

The fragile X syndrome: Isolation of the FMR-1 gene and characterization of the fragile X mutation

NARCIS (Netherlands)

B.A. Oostra (Ben); A. Verkerk

1992-01-01

markdownabstractConclusion Rapid progress has been made in the analysis of the fragile X syndrome during 1991. Different groups have discovered that fragile X chromosomes are preferentially methylated. In these X chromosomes an insertion has been found in the methylated region. The FMR-1 gene,

21st-Century Citizen Science

Science.gov (United States)

Nugent, Jill; Smith, Walter; Cook, Linda; Bell, Meredith

2015-01-01

With rapidly evolving technology, the world is more connected than ever, and citizens around the globe can contribute to science like never before (Dickinson and Bonney 2012). Reflecting the growing capacity of citizen science, this article presents a science education continuum that moves from global awareness to global contribution. At each…

Energy Flow and Rapidity Gaps Between Jets in Photoproduction at HERA

CERN Document Server

Adloff, C.; Andrieu, B.; Anthonis, T.; Arkadov, V.; Astvatsatourov, A.; Babaev, A.; Bahr, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bate, P.; Becker, J.; Beglarian, A.; Behnke, O.; Beier, C.; Belousov, A.; Benisch, T.; Berger, C.; Berndt, T.; Bizot, J.C.; Boehme, J.; Boudry, V.; Braunschweig, W.; Brisson, V.; Broker, H.B.; Brown, D.P.; Bruckner, W.; Bruncko, D.; Burger, J.; Busser, F.W.; Bunyatyan, A.; Burrage, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cao, Jun; Caron, S.; Cassol-Brunner, F.; Clarke, D.; Collard, C.; Contreras, J.G.; Coppens, Y.R.; Coughlan, J.A.; Cousinou, M.C.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; Davidsson, M.; Delcourt, B.; Delerue, N.; Demirchyan, R.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dingfelder, J.; Dixon, P.; Dodonov, V.; Dowell, J.D.; Droutskoi, A.; Dubak, A.; Duprel, C.; Eckerlin, Guenter; Eckstein, D.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellerbrock, M.; Elsen, E.; Erdmann, M.; Erdmann, W.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Ferron, S.; Fleischer, M.; Fleming, Y.H.; Flugge, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Franke, G.; Gabathuler, E.; Gabathuler, K.; Garvey, J.; Gassner, J.; Gayler, Joerg; Gerhards, R.; Gerlich, C.; Ghazaryan, Samvel; Goerlich, L.; Gogitidze, N.; Grab, C.; Grassler, H.; Greenshaw, T.; Grindhammer, Guenter; Hadig, T.; Haidt, D.; Hajduk, L.; Haller, J.; Haynes, W.J.; Heinemann, B.; Heinzelmann, G.; Henderson, R.C.W.; Hengstmann, S.; Henschel, H.; Heremans, R.; Herrera, G.; Herynek, I.; Hildebrandt, M.; Hilgers, M.; Hiller, K.H.; Hladky, J.; Hoting, P.; Hoffmann, D.; Horisberger, R.; Hurling, S.; Ibbotson, M.; Issever, C .; Jacquet, M.; Jaffre, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, C.; Johnson, D.P.; Jones, M.A.S.; Jung, H.; Kant, D.; Kapichine, M.; Karlsson, M.; Karschnick, O.; Keil, F.; Keller, N.; Kennedy, J.; Kenyon, I.R.; Kermiche, S.; Kiesling, Christian M.; Kjellberg, P.; Klein, M.; Kleinwort, C.; Kluge, T.; Knies, G.; Koblitz, B.; Kolya, S.D.; Korbel, V.; Kostka, P.; Kotelnikov, S.K.; Koutouev, R.; Koutov, A.; Krehbiel, H.; Kroseberg, J.; Kruger, K.; Kupper, A.; Kuhr, T.; Kurca, T.; Lamb, D.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Laycock, P.; Lebailly, E.; Lebedev, A.; Leissner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindstroem, M.; List, B.; Lobodzinska, E.; Lobodzinski, B.; Loginov, A.; Loktionova, N.; Lubimov, V.; Luders, S.; Luke, D.; Lytkin, L.; Mahlke-Kruger, H.; Malden, N.; Malinovski, E.; Malinovski, I.; Maracek, R.; Marage, P.; Marks, J.; Marshall, R.; Martyn, H.U.; Martyniak, J.; Maxfield, S.J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Meyer, P.O.; Mikocki, S.; Milstead, D.; Mkrtchyan, T.; Mohr, R.; Mohrdieck, S.; Mondragon, M.N.; Moreau, F.; Morozov, A.; Morris, J.V.; Muller, K.; Murin, P.; Nagovizin, V.; Naroska, B.; Naumann, J.; Naumann, T.; Nellen, G.; Newman, Paul R.; Nicholls, T.C.; Niebergall, F.; Niebuhr, C.; Nix, O.; Nowak, G.; Olsson, J.E.; Ozerov, D.; Panassik, V.; Pascaud, C.; Patel, G.D.; Peez, M.; Perez, E.; Phillips, J.P.; Pitzl, D.; Poschl, R.; Potachnikova, I.; Povh, B.; Radel, G.; Rauschenberger, J.; Reimer, P.; Reisert, B.; Reyna, D.; Risler, C.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rusakov, S.; Rybicki, K.; Sankey, D.P.C.; Schatzel, S.; Scheins, J.; Schilling, F.P.; Schleper, P.; Schmidt, D.; Schmidt, S.; Schmitt, S.; Schneider, M.; Schoeffel, L.; Schoning, A.; Schorner, T.; Schroder, V.; Schultz-Coulon, H.C.; Schwanenberger, C.; Sedlak, K.; Sefkow, F.; Chekelian, V.; Sheviakov, I.; Shtarkov, L.N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Spitzer, H.; Stamen, R.; Stella, B.; Stiewe, J.; Straumann, U.; Swart, M.; Tasevsky, M.; Tchetchelnitski, S.; Thompson, Graham; Thompson, P.D.; Tobien, N.; Traynor, D.; Truoel, Peter; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Turney, J.E.; Tzamariudaki, E.; Udluft, S.; Urban, Marcel; Usik, A.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vassiliev, S.; Vazdik, Y.; Vichnevski, A.; Wacker, K.; Wagner, J.; Wallny, R.; Waugh, B.; Weber, G.; Weber, M.; Wegener, D.; Werner, C.; Werner, M.; Werner, N.; Wessels, M.; White, G.; Wiesand, S.; Wilksen, T.; Winde, M.; Winter, G.G.; Wissing, C.; Wobisch, M.; Woehrling, E.E.; Wunsch, E.; Wyatt, A.C.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zomer, F.; zur Nedden, M.

2002-01-01

Dijet events in photon-proton collisions in which there is a large pseudorapidity separation Delta eta > 2.5 between the two highest E_T jets are studied with the H1 detector at HERA. The inclusive dijet cross sections are measured as functions of the longitudinal momentum fractions of the proton and photon which participate in the production of the jets, x_pjet and x_gjet respectively, Delta eta, the pseudorapidity separation between the two highest E_T jets, and E_T^gap, the total summed transverse energy between the jets. Rapidity gap events are defined as events in which E_T^gap is less than E_T^cut, for E_T^cut varied between 0.5 and 2.0 GeV. The fraction of dijet events with a rapidity gap is measured differentially in Delta eta, x_pjet and x_gjet. An excess of events with rapidity gaps at low values of E_T^cut is observed above the expectation from standard photoproduction processes. This excess can be explained by the exchange of a strongly interacting colour singlet object between the jets.

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 39; Issue 7. Theoretical study of built-in-polarization effect on relaxation time and mean free path of phonons in Al x Ga 1 − x N alloy. B K SAHOO A PANSARI. Volume 39 Issue 7 December 2016 pp 1835-1841 ...

Science Outreach for the Thousands: Coe College's Playground of Science

Science.gov (United States)

Watson, D. E.; Franke, M.; Affatigato, M.; Feller, S.

2011-12-01

Coe College is a private liberal arts college nestled in the northeast quadrant of Cedar Rapids, IA. Coe takes pride in the outreach it does in the local community. The sciences at Coe find enjoyment in educating the children and families of this community through a diverse set of venues; from performing science demonstrations for children at Cedar Rapids' Fourth of July Freedom Festival to hosting summer forums and talks to invigorate the minds of its more mature audiences. Among these events, the signature event of the year is the Coe Playground of Science. On the last Thursday of October, before Halloween, the science departments at Coe invite nearly two thousand children from pre elementary to high school ages, along with their parents to participate in a night filled with science demos, haunted halls, and trick-or-treating for more than just candy. The demonstrations are performed by professors and students alike from a raft of cooperative departments including physics, chemistry, biology, math, computer science, nursing, ROTC, and psychology. This event greatly strengthens the relationships between institution members and community members. The sciences at Coe understand the importance of imparting the thrill and hunger for exploration and discovery into the future generations. More importantly they recognize that this cannot start and end at the collegiate level, but the American public must be reached at younger ages and continue to be encouraged beyond the college experience. The Playground of Science unites these two groups under the common goal of elevating scientific interest in the American people.

Integrating Rapid Prototyping into Graphic Communications

Science.gov (United States)

Xu, Renmei; Flowers, Jim

2015-01-01

Integrating different science, technology, engineering, and mathematics (STEM) areas can help students learn and leverage both the equipment and expertise at a single school. In comparing graphic communications classes with classes that involve rapid prototyping (RP) technologies like 3D printing, there are sufficient similarities between goals,…

Characterizing Intermediate-Mass, Pre-Main-Sequence Stars via X-Ray Emision

Science.gov (United States)

Haze Nunez, Evan; Povich, Matthew Samuel; Binder, Breanna Arlene; Broos, Patrick; Townsley, Leisa K.

2018-01-01

The X-ray emission from intermediate-mass, pre-main-sequence stars (IMPS) can provide useful constraints on the ages of very young (${getting power from the gravitational contraction of the star. Main-sequence late-B and A-type stars are not expected to be strong X-ray emitters, because they lack the both strong winds of more massive stars and the magneto-coronal activity of lower-mass stars. There is, however, mounting evidence that IMPS are powerful intrinsic x-ray emitters during their convection-dominated early evolution, before the development and rapid growth of a radiation zone. We present our prime candidates for intrinsic, coronal X-ray emission from IMPS identified in the Chandra Carina Complex Project. The Carina massive star-forming complex is of special interest due to the wide variation of star formation stages within the region. Candidate IMPS were identified using infrared spectral energy distribution (SED) models. X-ray properties, including thermal plasma temperatures and absorption-corrected fluxes, were derived from XSPEC fits performed using absorption ($N_{H}$) constrained by the extinction values returned by the infrared SED fits. We find that IMPS have systematically higher X-ray luminosities compared to their lower-mass cousins, the TTauri stars.This work is supported by the National Science Foundation under grant CAREER-1454334 and by NASA through Chandra Award 18200040.

Central Laboratory of X-ray and Electron Microscopy Research at the Institute of Physics of the Polish Academy of Sciences, Warsaw

International Nuclear Information System (INIS)

Zymierska, D.

2008-01-01

The beginning and history of the Central Laboratory of X-ray and Electron Microscopy at the Institute of Physics of the Polish Academy of Sciences in Warsaw is described. Then, recent scientific achievements are presented. Organising activities of the Laboratory staff are also mentioned. (author)

NASA Planetary Science Summer School: Preparing the Next Generation of Planetary Mission Leaders

Science.gov (United States)

Lowes, L. L.; Budney, C. J.; Sohus, A.; Wheeler, T.; Urban, A.; NASA Planetary Science Summer School Team

2011-12-01

Sponsored by NASA's Planetary Science Division, and managed by the Jet Propulsion Laboratory, the Planetary Science Summer School prepares the next generation of engineers and scientists to participate in future solar system exploration missions. Participants learn the mission life cycle, roles of scientists and engineers in a mission environment, mission design interconnectedness and trade-offs, and the importance of teamwork. For this professional development opportunity, applicants are sought who have a strong interest and experience in careers in planetary exploration, and who are science and engineering post-docs, recent PhDs, and doctoral students, and faculty teaching such students. Disciplines include planetary science, geoscience, geophysics, environmental science, aerospace engineering, mechanical engineering, and materials science. Participants are selected through a competitive review process, with selections based on the strength of the application and advisor's recommendation letter. Under the mentorship of a lead engineer (Dr. Charles Budney), students select, design, and develop a mission concept in response to the NASA New Frontiers Announcement of Opportunity. They develop their mission in the JPL Advanced Projects Design Team (Team X) environment, which is a cross-functional multidisciplinary team of professional engineers that utilizes concurrent engineering methodologies to complete rapid design, analysis and evaluation of mission concept designs. About 36 students participate each year, divided into two summer sessions. In advance of an intensive week-long session in the Project Design Center at JPL, students select the mission and science goals during a series of six weekly WebEx/telecons, and develop a preliminary suite of instrumentation and a science traceability matrix. Students assume both a science team and a mission development role with JPL Team X mentors. Once at JPL, students participate in a series of Team X project design sessions

Towards Data Science

OpenAIRE

Zhu, Yangyong; Xiong, Yun

2015-01-01

Currently, a huge amount of data is being rapidly generated in cyberspace. Datanature (all data in cyberspace) is forming due to a data explosion. Exploring the patterns and rules in datanature is necessary but difficult. A new discipline called Data Science is coming. It provides a type of novel research method (a data-intensive method) for natural and social sciences and goes beyond computer science in researching data. This paper presents the challenges presented by data and discusses what...

X-ray was on the verge of discovery

International Nuclear Information System (INIS)

Vuoria, P.

1995-01-01

It is no coincidence that x-radiation was discovered in the late 19th century. Electrical phenomena were under vigorous study at the time. It was a heyday for universities; natural sciences advanced rapidly, and the increasing wealth in society sped up research in various fields. If Roentgen had not discovered the x-rays, some other researcher would certainly have found them around the same time. People were enthralled by x-rays, and the general climate in the early years did not favour advocating for radiation protection, even though a hundred years ago it was already recognised that radiation also poses a risk to health. In addition to improved knowledge and advanced technology, more efficient control measures by the authorities have also helped to improve radiation protection gradually. Study of the damage to health caused by the atomic bombs in Hiroshima and Nagasaki has substantially enhanced the body of knowledge on radiation protection. The whole spectrum of electromagnetic radiation has gradually opened up to researchers. The effects of rays on the body vary greatly, depending on their wavelength. Considerable amounts of x- radiation have also been detected in space. The effects of these x-rays on people are mostly eliminated by the atmosphere. When radiation is used safely, a carefully conducted x-ray examination always has far more advantages than disadvantages. Nowadays it is also possible to utilise contrast mediums and magnetic imaging. Magnetic fields and the radio-frequency waves used in magnetic imaging have not been found to cause any permanent damage to the body. It may well be that in future magnetic imaging will replace all x-ray examinations. (orig.) (2 figs.)

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 39; Issue 5. Structure and magnetic properties of Zr–Mn substituted strontium hexaferrite Sr(Zr,Mn) x Fe 12 − 2 x O 19 nanoparticles synthesized by sol–gel auto-combustion method. S ALAMOLHODA S M MIRKAZEMI Z GHIAMI M NIYAIFAR. Volume 39 Issue 5 ...

Citizen Science Initiatives: Engaging the Public and Demystifying Science

Directory of Open Access Journals (Sweden)

Kim Van Vliet

2015-12-01

Full Text Available The Internet and smart phone technologies have opened up new avenues for collaboration among scientists around the world. These technologies have also expanded citizen science opportunities and public participation in scientific research (PPSR. Here we discuss citizen science, what it is, who does it, and the variety of projects and methods used to increase scientific knowledge and scientific literacy. We describe a number of different types of citizen-science projects. These greatly increase the number of people involved, helping to speed the pace of data analysis and allowing science to advance more rapidly. As a result of the numerous advantages of citizen-science projects, these opportunities are likely to expand in the future and increase the rate of novel discoveries.

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Earth System Science; Volume 121; Issue 5 ... owing to rugged terrain at high altitude, high frequency of intense rainfall and rapidly ... School of Civil Engineering, SASTRA University, Thanjavur, Tamilnadu, India.

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 39; Issue 1. Preparation of new thermoluminescent material ( 100 − x )B 2 O 3 –xLi 2 O: Cu 2 + for sensing and detection of radiation. Zeid A Alothman Tansir Ahamad Mu Naushad Saad M Alshehri. Volume 39 Issue 1 February 2016 pp 331-336 ...

Rapid molecular cytogenetic analysis of X-chromosomal microdeletions: Fluorescence in situ hybridization (FISH) for complex glycerol kinase deficiency

Energy Technology Data Exchange (ETDEWEB)

Worley, K.C.; Lindsay, E.A.; McCabe, E.R.B. [Baylor College of Medicine, Houston, TX (United States)] [and others

1995-07-17

Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring time-consuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita. We report an improved method for diagnosis of deletions in individuals with CGKD and for identification of female carriers within their families using fluorescence in situ hybridization (FISH) with a cosmid marker (cosmid 35) within the glycerol kinase gene. When used in combination with an Xq control probe, affected males demonstrate a single signal from the control probe, while female carriers demonstrate a normal chromosome with two signals, as well as a deleted chromosome with a single signal from the control probe. FISH analysis for CGKD provides the advantages of speed and accuracy for evaluation of submicroscopic X-chromosome deletions, particularly in identification of female carriers. In addition to improving carrier evaluation, FISH will make prenatal diagnosis of CGKD more readily available. 17 refs., 2 figs.

Phase change materials science and applications

CERN Document Server

Raoux, Simone

2009-01-01

""Phase Change Materials: Science and Applications"" provides a unique introduction of this rapidly developing field. This clearly written volume describes the material science of these fascinating materials from a theoretical and experimental perspective.

Primes of the form x2 + dy2 with x ≡ 0(mod N)

Indian Academy of Sciences (India)

Department of Computer Science and Automation, Indian Institute of Science, ... This led many mathematicians to work on primes of the form x2 + dy2 for d = 2, 3, 5, 7 ..... Chandan Singh Dalawat, H.R.I. Allahabad, for the kind help and.

Laboratory and In-Flight In-Situ X-ray Imaging and Scattering Facility for Materials, Biotechnology and Life Sciences

Science.gov (United States)

2003-01-01

We propose a multifunctional X-ray facility for the Materials, Biotechnology and Life Sciences Programs to visualize formation and behavior dynamics of materials, biomaterials, and living organisms, tissues and cells. The facility will combine X-ray topography, phase micro-imaging and scattering capabilities with sample units installed on the goniometer. This should allow, for the first time, to monitor under well defined conditions, in situ, in real time: creation of imperfections during growth of semiconductors, metal, dielectric and biomacromolecular crystals and films, high-precision diffraction from crystals within a wide range of temperatures and vapor, melt, solution conditions, internal morphology and changes in living organisms, tissues and cells, diffraction on biominerals, nanotubes and particles, radiation damage, also under controlled formation/life conditions. The system will include an ultrabright X-ray source, X-ray mirror, monochromator, image-recording unit, detectors, and multipurpose diffractometer that fully accommodate and integrate furnaces and samples with other experimental environments. The easily adjustable laboratory and flight versions will allow monitoring processes under terrestrial and microgravity conditions. The flight version can be made available using a microsource combined with multilayer or capillary optics.

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. F Wang. Articles written in Bulletin of Materials Science. Volume 34 Issue 5 August 2011 pp 1033-1037. Synthesis of Mn-doped CeO2 nanorods and their application as humidity sensors · C H Hu C H Xia F Wang M Zhou P F Yin X Y Han · More Details Abstract Fulltext PDF.

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. C H Xia. Articles written in Bulletin of Materials Science. Volume 34 Issue 5 August 2011 pp 1033-1037. Synthesis of Mn-doped CeO2 nanorods and their application as humidity sensors · C H Hu C H Xia F Wang M Zhou P F Yin X Y Han · More Details Abstract Fulltext PDF.

The X-ray Astronomy Recovery Mission

Science.gov (United States)

Tashiro, M.; Kelley, R.

2017-10-01

On 25 March 2016, the Japanese 6th X-ray astronomical satellite ASTRO-H (Hitomi), launched on February 17, lost communication after a series of mishap in its attitude control system. In response to the mishap the X-ray astronomy community and JAXA analyzed the direct and root cause of the mishap and investigated possibility of a recovery mission with the international collaborator NASA and ESA. Thanks to great effort of scientists, agencies, and governments, the X-ray Astronomy Recovery Mission (XARM) are proposed. The recovery mission is planned to resume high resolution X-ray spectroscopy with imaging realized by Hitomi under the international collaboration in the shortest time possible, simply by focusing one of the main science goals of Hitomi Resolving astrophysical problems by precise high-resolution X-ray spectroscopy'. XARM will carry a 6 x 6 pixelized X-ray micro-calorimeter on the focal plane of an X-ray mirror assembly, and an aligned X-ray CCD camera covering the same energy band and wider field of view, but no hard X-ray or soft gamma-ray instruments are onboard. In this paper, we introduce the science objectives, mission concept, and schedule of XARM.

Career and Workforce Impacts of the NASA Planetary Science Summer School: TEAM X model 1999-2015

Science.gov (United States)

Lowes, Leslie L.; Budney, Charles; Mitchell, Karl; Wessen, Alice; JPL Education Office, JPL Team X

2016-10-01

Sponsored by NASA's Planetary Science Division, and managed by the Jet Propulsion Laboratory (JPL), the Planetary Science Summer School prepares the next generation of engineers and scientists to participate in future solar system exploration missions. PSSS utilizes JPL's emerging concurrent mission design "Team X" as mentors. With this model, participants learn the mission life cycle, roles of scientists and engineers in a mission environment, mission design interconnectedness and trade-offs, and the importance of teamwork. Applicants are sought who have a strong interest and experience in careers in planetary exploration, and who are science and engineering post-docs, recent PhDs, doctoral or graduate students, and faculty teaching such students. An overview of the program will be presented, along with results of a diversity study conducted in fall 2015 to assess the gender and ethnic diversity of participants since 1999. PSSS seeks to have a positive influence on participants' career choice and career progress, and to help feed the employment pipeline for NASA, aerospace, and related academia. Results will also be presented of an online search that located alumni in fall 2015 related to their current occupations (primarily through LinkedIn and university and corporate websites), as well as a 2015 survey of alumni.

Female human pluripotent stem cells rapidly lose X chromosome inactivation marks and progress to a skewed methylation pattern during culture.

Science.gov (United States)

Geens, M; Seriola, A; Barbé, L; Santalo, J; Veiga, A; Dée, K; Van Haute, L; Sermon, K; Spits, C

2016-04-01

Does a preferential X chromosome inactivation (XCI) pattern exist in female human pluripotent stem cells (hPSCs) and does the pattern change during long-term culture or upon differentiation? We identified two independent phenomena that lead to aberrant XCI patterns in female hPSC: a rapid loss of histone H3 lysine 27 trimethylation (H3K27me3) and long non-coding X-inactive specific transcript (XIST) expression during culture, often accompanied by erosion of XCI-specific methylation, and a frequent loss of random XCI in the cultures. Variable XCI patterns have been reported in female hPSC, not only between different hPSC lines, but also between sub-passages of the same cell line, however the reasons for this variability remain unknown. Moreover, while non-random XCI-linked DNA methylation patterns have been previously reported, their origin and extent have not been investigated. We investigated the XCI patterns in 23 human pluripotent stem cell (hPSC) lines, during long-term culture and after differentiation, by gene expression analysis, histone modification assessment and study of DNA methylation. The presence and location of H3K27me3 was studied by immunofluorescence, XIST expression by real-time PCR, and mono- or bi-allelic expression of X-linked genes was studied by sequencing of cDNA. XCI-specific DNA methylation was analysed using methylation-sensitive restriction and PCR, and more in depth by massive parallel bisulphite sequencing. All hPSC lines showed XCI, but we found a rapid loss of XCI marks during the early stages of in vitro culture. While this loss of XCI marks was accompanied in several cases by an extensive erosion of XCI-specific methylation, it did not result in X chromosome reactivation. Moreover, lines without strong erosion of methylation frequently displayed non-random DNA methylation, which occurred independently from the loss of XCI marks. This bias in X chromosome DNA methylation did not appear as a passenger event driven by clonal culture

Development of the Simbol-X science verification model and its contribution for the IXO Mission

Science.gov (United States)

Maier, Daniel; Aschauer, Florian; Dick, Jürgen; Distratis, Giuseppe; Gebhardt, Henry; Herrmann, Sven; Kendziorra, Eckhard; Lauf, Thomas; Lechner, Peter; Santangelo, Andrea; Schanz, Thomas; Strüder, Lothar; Tenzer, Chris; Treis, Johannes

2010-07-01

Like the International X-ray Observatory (IXO) mission, the Simbol-X mission is a projected X-ray space telescope with spectral and imaging capabilities covering the energy range from 500 eV up to 80 keV. To detect photons within this wide range of energies, a silicon based "Depleted P-channel Field Effect Transistor" (DePFET)- matrix is used as the Low Energy Detector (LED) on top of an array of CdTe-Caliste modules, which act as the High Energy Detector (HED). A Science Verification Model (SVM) consisting of one LED quadrant in front of one Caliste module will be set up at our institute (IAAT) and operated under laboratory conditions that approximate the expected environment in space. As a first step we use the SVM to test and optimize the performance of the LED operation and data acquisition chain, consisting of an ADC, an event-preprocessor, a sequencer, and an interface controller. All these components have been developed at our institute with the objective to handle the high readout rate of approximately 8000 frames per second. The second step is to study the behaviour and the interactions of LED and HED operating as a combined detector system. We report on the development status of the SVM and its associated electronics and present first results of the currently achieved spectral performance.

Rapid X-ray and optical variability in the X-ray selected BL Lacertae object IE 1402.3 + 0416

International Nuclear Information System (INIS)

Giommi, P.; Barr, P.; Gioia, I.M.; Maccacaro, T.; Schild, R.; Harvard-Smithsonian Center for Astrophysics, Cambridge)

1986-01-01

Results from X-ray and optical observations of the X-ray-discovered BL Lac object 1E 1402.3 + 0416 are presented, where the X-ray measurements were carried out with the Channel Multiplier Array (CMA) and Medium Energy experiment (ME) detectors on board Exosat. These measurements revealed an intensity decrease by a factor of two on a time scale of a few hours. At maximum flux, the source was significantly greater than at the time of the Einstein Image Proportional Counter (IPC) discovery observation. The 2-6 keV X-ray spectrum was determined by the ME experiment, and IPC, HRI, and CMA data were subsequently compared. The source varied over the years by a factor of five; its brightest state was within the last three years. It is noted that a redshift greater than 0.2 would require that anisotropic emission mechanisms be invoked. 18 references

HIGH-PERFORMANCE COMPUTING FOR THE STUDY OF EARTH AND ENVIRONMENTAL SCIENCE MATERIALS USING SYNCHROTRON X-RAY COMPUTED MICROTOMOGRAPHY

International Nuclear Information System (INIS)

FENG, H.; JONES, K.W.; MCGUIGAN, M.; SMITH, G.J.; SPILETIC, J.

2001-01-01

Synchrotron x-ray computed microtomography (CMT) is a non-destructive method for examination of rock, soil, and other types of samples studied in the earth and environmental sciences. The high x-ray intensities of the synchrotron source make possible the acquisition of tomographic volumes at a high rate that requires the application of high-performance computing techniques for data reconstruction to produce the three-dimensional volumes, for their visualization, and for data analysis. These problems are exacerbated by the need to share information between collaborators at widely separated locations over both local and tide-area networks. A summary of the CMT technique and examples of applications are given here together with a discussion of the applications of high-performance computing methods to improve the experimental techniques and analysis of the data

HIGH-PERFORMANCE COMPUTING FOR THE STUDY OF EARTH AND ENVIRONMENTAL SCIENCE MATERIALS USING SYNCHROTRON X-RAY COMPUTED MICROTOMOGRAPHY.

Energy Technology Data Exchange (ETDEWEB)

FENG,H.; JONES,K.W.; MCGUIGAN,M.; SMITH,G.J.; SPILETIC,J.

2001-10-12

Synchrotron x-ray computed microtomography (CMT) is a non-destructive method for examination of rock, soil, and other types of samples studied in the earth and environmental sciences. The high x-ray intensities of the synchrotron source make possible the acquisition of tomographic volumes at a high rate that requires the application of high-performance computing techniques for data reconstruction to produce the three-dimensional volumes, for their visualization, and for data analysis. These problems are exacerbated by the need to share information between collaborators at widely separated locations over both local and tide-area networks. A summary of the CMT technique and examples of applications are given here together with a discussion of the applications of high-performance computing methods to improve the experimental techniques and analysis of the data.

Rapid manufacturing for microfluidics

CSIR Research Space (South Africa)

Land, K

2012-10-01

Full Text Available for microfluidics K. LAND, S. HUGO, M MBANJWA, L FOURIE CSIR Materials Science and Manufacturing P O Box 395, Pretoria 0001, SOUTH AFRICA Email: kland@csir.co.za INTRODUCTION Microfluidics refers to the manipulation of very small volumes of fluid.... Microfluidics is at the forefront of developing solutions for drug discovery, diagnostics (from glucose tests to malaria and TB testing) and environmental diagnostics (E-coli monitoring of drinking water). In order to quickly implement new designs, a rapid...

Toward Control of Matter: Basic Energy Science Needs for a New Class of X-Ray Light Sources

Energy Technology Data Exchange (ETDEWEB)

Arenholz, Elke; Belkacem, Ali; Cocke, Lew; Corlett, John; Falcone, Roger; Fischer, Peter; Fleming, Graham; Gessner, Oliver; Hasan, M. Zahid; Hussain, Zahid; Kevan, Steve; Kirz, Janos; McCurdy, Bill; Nelson, Keith; Neumark, Dan; Nilsson, Anders; Siegmann, Hans; Stocks, Malcolm; Schafer, Ken; Schoenlein, Robert; Spence, John; Weber, Thorsten

2008-09-24

Over the past quarter century, light-source user facilities have transformed research in areas ranging from gas-phase chemical dynamics to materials characterization. The ever-improving capabilities of these facilities have revolutionized our ability to study the electronic structure and dynamics of atoms, molecules, and even the most complex new materials, to understand catalytic reactions, to visualize magnetic domains, and to solve protein structures. Yet these outstanding facilities still have limitations well understood by their thousands of users. Accordingly, over the past several years, many proposals and conceptual designs for"next-generation" x-ray light sources have been developed around the world. In order to survey the scientific problems that might be addressed specifically by those new light sources operating below a photon energy of about 3 keV and to identify the scientific requirements that should drive the design of such facilities, a workshop"Science for a New Class of Soft X-Ray Light Sources" was held in Berkeley in October 2007. From an analysisof the most compelling scientific questions that could be identified and the experimental requirements for answering them, we set out to define, without regard to the specific technologies upon which they might be based, the capabilities such light sources would have to deliver in order to dramatically advance the state of research in the areas represented in the programs of the Department of Energy's Office of Basic Energy Sciences (BES). This report is based on the workshop presentations and discussions.

Toward Control of Matter: Basic Energy Science Needs for a New Class of X-Ray Light Sources

International Nuclear Information System (INIS)

Arenholz, Elke; Belkacem, Ali; Cocke, Lew; Corlett, John; Falcone, Roger; Fischer, Peter; Fleming, Graham; Gessner, Oliver; Hasan, M. Zahid; Hussain, Zahid; Kevan, Steve; Kirz, Janos; McCurdy, Bill; Nelson, Keith; Neumark, Dan; Nilsson, Anders; Siegmann, Hans; Stocks, Malcolm; Schafer, Ken; Schoenlein, Robert; Spence, John; Weber, Thorsten

2008-01-01

Over the past quarter century, light-source user facilities have transformed research in areas ranging from gas-phase chemical dynamics to materials characterization. The ever-improving capabilities of these facilities have revolutionized our ability to study the electronic structure and dynamics of atoms, molecules, and even the most complex new materials, to understand catalytic reactions, to visualize magnetic domains, and to solve protein structures. Yet these outstanding facilities still have limitations well understood by their thousands of users. Accordingly, over the past several years, many proposals and conceptual designs for 'next-generation' x-ray light sources have been developed around the world. In order to survey the scientific problems that might be addressed specifically by those new light sources operating below a photon energy of about 3 keV and to identify the scientific requirements that should drive the design of such facilities, a workshop 'Science for a New Class of Soft X-Ray Light Sources' was held in Berkeley in October 2007. From an analysis of the most compelling scientific questions that could be identified and the experimental requirements for answering them, we set out to define, without regard to the specific technologies upon which they might be based, the capabilities such light sources would have to deliver in order to dramatically advance the state of research in the areas represented in the programs of the Department of Energy's Office of Basic Energy Sciences (BES). This report is based on the workshop presentations and discussions

Measurement of the shape of the boson rapidity distribution for $p\\bar{p} \\rightarrow Z/\\gamma^{*} \\rightarrow e^{+}e^{-} + X$ events produced at $\\sqrt{s} =1.96$ TeV

Energy Technology Data Exchange (ETDEWEB)

Ding, Pengfei [Univ. of Manchester (United Kingdom)

2013-09-01

The measurement of the shape of the boson rapidity distribution for p $\\bar{p}$ → Z/γ* → e⁺e^- + X events at a center-of-mass energy of 1.96 TeV is presented in this thesis. Data, with an integrated luminosity of L = 9.86 fb^-1, collected with the D0 detector during the whole RunII data taking period of the Fermilab Tevatron p$\\bar{p}$ collider has been used. The measurement is made for events with electron-positron mass 66 < M_ee < 111 GeV. The current result gives the best precision of the boson rapidity shape at the Tevatron. It signi cantly reduces the uncertainty in the boson rapidity range |y| > 2:3. Predictions of Next-to- Leading-Order (NLO) QCD theory with CTEQ and MSTW parton distribution functions are found to agree well with the data over the full rapidity range.

SMART-X: Square Meter, Arcsecond Resolution Telescope for X-rays

Science.gov (United States)

Vikhlinin, Alexey; SMART-X Collaboration

2013-04-01

SMART-X is a concept for a next-generation X-ray observatory with large-area, 0.5" angular resolution grazing incidence adjustable X-ray mirrors, high-throughput critical angle transmission gratings, and X-ray microcalorimeter and CMOS-based imager in the focal plane. High angular resolution is enabled by new technology based on controlling the shape of mirror segments using thin film piezo actuators deposited on the back surface. Science applications include observations of growth of supermassive black holes since redshifts of ~10, ultra-deep surveys over 10's of square degrees, galaxy assembly at z=2-3, as well as new opportunities in the high-resolution X-ray spectroscopy and time domains. We also review the progress in technology development, tests, and mission design over the past year.

Novel X-ray telescopes for wide-field X-ray monitoring

International Nuclear Information System (INIS)

Hudec, R.; Inneman, A.; Pina, L.; Sveda, L.

2005-01-01

We report on fully innovative very wide-field of view X-ray telescopes with high sensitivity as well as large field of view. The prototypes are very promising, allowing the proposals for space projects with very wide-field Lobster-eye X-ray optics to be considered. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study and to understand various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. The Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science

Three-Dimensional X-Ray Diffraction Technique for Metals Science

DEFF Research Database (Denmark)

Zhang, Yubin; Fan, Guohua

2017-01-01

The three-dimensional X-ray diffraction (3DXRD) is a new, advanced technique for materials characterization. This technique utilizes high-energy synchrotron X-rays to characterize the 3D crystallographic structure and strain/stress state of bulk materials. As the measurement is non......-destructive, the microstructural evolution as a function of time can be followed, i.e. it allows 4D (x, y, z characterizations, t). The high brilliance of synchrotron X-rays ensures that diffraction signals from volumes of micrometer scale can be quickly detected and distinguished from the background noise, i.e. its spatial...... implemented in several large synchrotron facilities, e.g. the Advanced Photon Source (APS) in USA and the Spring-8 in Japan. Another family of 3DXRD technique that utilizes white beam synchrotron X-rays has also been developed in parallel in cooperation between Oak Ridge National Laboratory and APS...

Rapid Quench in an Electrostatic Levitator

Science.gov (United States)

SanSoucie, Michael P.; Rogers, Jan R.; Matson, Douglas M.

2016-01-01

The Electrostatic Levitation (ESL) Laboratory at the NASA Marshall Space Flight Center (MSFC) is a unique facility for investigators studying high-temperature materials. The ESL laboratory's main chamber has been upgraded with the addition of a rapid quench system. This system allows samples to be dropped into a quench vessel that can be filled with a low melting point material, such as a gallium or indium alloy, as a quench medium. Thereby allowing rapid quenching of undercooled liquid metals. Up to eight quench vessels can be loaded into a wheel inside the chamber that is indexed with control software. The system has been tested successfully with samples of zirconium, iron-cobalt alloys, titanium-zirconium-nickel alloys, and a silicon-cobalt alloy. This new rapid quench system will allow materials science studies of undercooled materials and new materials development. In this presentation, the system is described and some initial results are presented.

Portable XRF and principal component analysis for bill characterization in forensic science.

Science.gov (United States)

Appoloni, C R; Melquiades, F L

2014-02-01

Several modern techniques have been applied to prevent counterfeiting of money bills. The objective of this study was to demonstrate the potential of Portable X-ray Fluorescence (PXRF) technique and the multivariate analysis method of Principal Component Analysis (PCA) for classification of bills in order to use it in forensic science. Bills of Dollar, Euro and Real (Brazilian currency) were measured directly at different colored regions, without any previous preparation. Spectra interpretation allowed the identification of Ca, Ti, Fe, Cu, Sr, Y, Zr and Pb. PCA analysis separated the bills in three groups and subgroups among Brazilian currency. In conclusion, the samples were classified according to its origin identifying the elements responsible for differentiation and basic pigment composition. PXRF allied to multivariate discriminate methods is a promising technique for rapid and no destructive identification of false bills in forensic science. Copyright © 2013 Elsevier Ltd. All rights reserved.

Applications of RIGAKU Dmax Rapid II micro-X-ray diffractometer in the analysis of archaeological metal objects

Science.gov (United States)

Mozgai, Viktória; Szabó, Máté; Bajnóczi, Bernadett; Weiszburg, Tamás G.; Fórizs, István; Mráv, Zsolt; Tóth, Mária

2017-04-01

During material analysis of archaeological metal objects, especially their inlays or corrosion products, not only microstructure and chemical composition, but mineralogical composition is necessary to be determined. X-ray powder diffraction (XRD) is a widely-used method to specify the mineralogical composition. However, when sampling is not or limitedly allowed due to e.g. the high value of the object, the conventional XRD analysis can hardly be used. Laboratory micro-XRD instruments provide good alternatives, like the RIGAKU Dmax Rapid II micro-X-ray diffractometer, which is a unique combination of a MicroMax-003 third generation microfocus, sealed tube X-ray generator and a curved 'image plate' detector. With this instrument it is possible to measure as small as 10 µm area in diameter on the object. Here we present case studies for the application of the micro-XRD technique in the study of archaeological metal objects. In the first case niello inlay of a Late Roman silver augur staff was analysed. Due to the high value of the object, since it is the only piece known from the Roman Empire, only non-destructive analyses were allowed. To reconstruct the preparation of the niello, SEM-EDX analysis was performed on the niello inlays to characterise their chemical composition and microstructure. Two types of niello are present: a homogeneous, silver sulphide niello (acanthite) and an inhomogeneous silver-copper sulphide niello (exsolution of acanthite and jalpaite or jalpaite and stromeyerite). The micro-X-ray diffractometer was used to verify the mineralogical composition of the niello, supposed on the base of SEM results. In the second case corrosion products of a Late Roman copper cauldron with uncertain provenance were examined, since they may hold clues about the burial conditions (pH, Eh, etc.) of the object. A layer by layer analysis was performed in cross sections of small metal samples by using electron microprobe and micro-X-ray diffractometer. The results

Simrank: Rapid and sensitive general-purpose k-mer search tool

Energy Technology Data Exchange (ETDEWEB)

DeSantis, T.Z.; Keller, K.; Karaoz, U.; Alekseyenko, A.V; Singh, N.N.S.; Brodie, E.L; Pei, Z.; Andersen, G.L; Larsen, N.

2011-04-01

Terabyte-scale collections of string-encoded data are expected from consortia efforts such as the Human Microbiome Project (http://nihroadmap.nih.gov/hmp). Intra- and inter-project data similarity searches are enabled by rapid k-mer matching strategies. Software applications for sequence database partitioning, guide tree estimation, molecular classification and alignment acceleration have benefited from embedded k-mer searches as sub-routines. However, a rapid, general-purpose, open-source, flexible, stand-alone k-mer tool has not been available. Here we present a stand-alone utility, Simrank, which allows users to rapidly identify database strings the most similar to query strings. Performance testing of Simrank and related tools against DNA, RNA, protein and human-languages found Simrank 10X to 928X faster depending on the dataset. Simrank provides molecular ecologists with a high-throughput, open source choice for comparing large sequence sets to find similarity.

Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

Energy Technology Data Exchange (ETDEWEB)

Jones, Keith W.

1999-09-01

Elemental analysis using emission of characteristic x rays is a well-established scientific method. The success of this analytical method is highly dependent on the properties of the source used to produce the x rays. X-ray tubes have long existed as a principal excitation source, but electron and proton beams have also been employed extensively. The development of the synchrotron radiation x-ray source that has taken place during the past 40 years has had a major impact on the general field of x-ray analysis. Even tier 40 years, science of x-ray analysis with synchrotron x-ray beams is by no means mature. Improvements being made to existing synchrotron facilities and the design and construction of new facilities promise to accelerate the development of the general scientific use of synchrotron x-ray sources for at least the next ten years. The effective use of the synchrotron source technology depends heavily on the use of high-performance computers for analysis and theoretical interpretation of the experimental data. Fortunately, computer technology has advanced at least as rapidly as the x-ray technology during the past 40 years and should continue to do so during the next decade. The combination of these technologies should bring about dramatic advances in many fields where synchrotron x-ray science is applied. It is interesting also to compare the growth and rate of acceptance of this particular research endeavor to the rates for other technological endeavors. Griibler [1997] cataloged the time required for introduction, diffusion,and acceptance of technological, economic, and social change and found mean values of 40 to 50 years. The introduction of the synchrotron source depends on both technical and non-technical factors, and the time scale at which this seems to be occurring is quite compatible with what is seen for other major innovations such as the railroad or the telegraph. It will be interesting to see how long the present rate of technological change

Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

International Nuclear Information System (INIS)

Jones, Keith W.

1999-01-01

Elemental analysis using emission of characteristic x rays is a well-established scientific method. The success of this analytical method is highly dependent on the properties of the source used to produce the x rays. X-ray tubes have long existed as a principal excitation source, but electron and proton beams have also been employed extensively. The development of the synchrotron radiation x-ray source that has taken place during the past 40 years has had a major impact on the general field of x-ray analysis. Even tier 40 years, science of x-ray analysis with synchrotron x-ray beams is by no means mature. Improvements being made to existing synchrotron facilities and the design and construction of new facilities promise to accelerate the development of the general scientific use of synchrotron x-ray sources for at least the next ten years. The effective use of the synchrotron source technology depends heavily on the use of high-performance computers for analysis and theoretical interpretation of the experimental data. Fortunately, computer technology has advanced at least as rapidly as the x-ray technology during the past 40 years and should continue to do so during the next decade. The combination of these technologies should bring about dramatic advances in many fields where synchrotron x-ray science is applied. It is interesting also to compare the growth and rate of acceptance of this particular research endeavor to the rates for other technological endeavors. Griibler [1997] cataloged the time required for introduction, diffusion,and acceptance of technological, economic, and social change and found mean values of 40 to 50 years. The introduction of the synchrotron source depends on both technical and non-technical factors, and the time scale at which this seems to be occurring is quite compatible with what is seen for other major innovations such as the railroad or the telegraph. It will be interesting to see how long the present rate of technological change

Lifting the veil on the X-ray universe

Science.gov (United States)

1999-11-01

. A multi-spectral space telescope The spacecraft carries three sets of science instruments, not only capable of making images of an X-ray source but also able to precisely distinguish the "colour" of the X-rays being viewed. At the prime focus of each of the telescopes are three European Photon Imaging Cameras. With silicon chips that can register extremely weak X-ray radiation, these advanced cameras are capable of detecting rapid variations in the intensity of a source. Grating structures at the exit of two mirror modules will reflect about half the incoming rays to a secondary focus, with its own cameras. This Reflection Grating Spectrometer will "fan out" the various wavelengths (much like a prism with visible light), and indicate in more detail the presence of individual elements, such as oxygen and iron. The third instrument aboard XMM is a conventional but very sensitive optical telescope. It will observe simultaneously the same regions as the X-ray telescopes but in the ultraviolet and visible wavelengths, giving astronomers complementary data about the X-ray sources being studied. In orbit, this 30-cm telescope will be as sensitive as a 4-m instrument on the Earth's surface. The mysteries of the X-ray sky XMM will explore the hidden depths of the Universe, its violent hotspots where stars and galaxies are formed, and where worlds and matter itself disappear. Much as the colour of a street lamp can indicate which gas it uses, the science instruments on board XMM will reveal the deepest secrets of X-ray objects, their chemical composition and temperatures - clues to the physical processes that are taking place. Astronomers will use XMM to resolve the mysteries of stars that exploded long ago as supernovae and whose remnants, glowing with X-rays, may be supplying material for new planets and stars. They will study regions of supernova remnants that are still hot and may hold the key to understanding the origin of the enigmatic cosmic rays that pervade the

New Roles for Scientists and Science Societies to Improve Science Communication

Science.gov (United States)

Schneider, S. H.

2008-12-01

Should North American Scientists and Science Societies continue with current communication programs or is there a need for expanded and or altered roles in Science Communication? If current practices are working, why is discourse outside of science societies so often misinformed and distorted on environmental change issues that are clearly defined and described within the science community? Climate change is one example there is virtual unanimity and overwhelming evidence from the scientific community that the Earth is warming rapidly and humans are an important cause, but there is confusion in the media and the public, in part due to disinformation campaigns by greenhouse gas polluters and privately funded "Think Tanks." A summary discussion will be presented that addresses many of the ideas and issues brought forward by colleagues in science, science communication and education. Scientists and Science Societies must re-establish objectivity in science information communication to educators, the media and the public. Recommendations on directions will be a key outcome of this presentation.

Science research with high-brilliance synchrotron light source

International Nuclear Information System (INIS)

Sanyal, Milan K.

2013-01-01

Synchrotron-science has changed dramatically since the development of high brilliance electron accelerator-based light sources in 1990s. In the last twenty years or so, several such facilities have come up, particularly in developed countries, as material characterizations in relevant atmosphere and protein crystallography with tiny-crystals have strong implications in industrial competitiveness. Moreover several new techniques have been developed recently over the entire spectral range of emitted light, from infra-red to high energy X-rays, which have altered our basic understanding of various materials like biomaterials, nanomaterials, soft-matter and semiconductor quantum structures. In addition, rapid development of various X-ray imaging techniques for nondestructive evaluation of compositional/structural homogeneity of engineering materials with nanometer resolution will have tremendous impact in manufacturing industries. As India becomes a developed country, it must have access to such an advanced synchrotron facility in the country that enables knowledge generation in the ever-expanding fields of design-characterization-production of advanced materials and modern medicines. Development of such state-of-the art facility will also enable us to carry out frontier-basic-research in our own country and help us to retain and bring back Indian talents to India. Here we shall discuss briefly the characteristics of a high brilliance synchrotron source and outline the nature of basic and applied science research that can be done with such a state-of-the-art facility. (author)

X-ray absorption fine structure (XAFS) spectroscopy: a tool for structural studies in material sciences (abstract)

International Nuclear Information System (INIS)

Akhtar, M.J.

2011-01-01

XAFS spectroscopy has revealed itself as a powerful technique for structural characterization of the local atomic environment of individual atomic species, including bond distances, coordination numbers and type of nearest neighbors surrounding the central atom. This technique is particularly useful for materials that show considerable structural and chemical disorder. XAFS spectroscopy has found extensive applications in determining the local atomic and electronic structure of the absorbing centers (atoms) in the materials science, physics, chemistry, biology and geophysics. X-ray absorption edges contain a variety of information on the chemical state and the local structure of the absorbing atom. On the higher energy side of an absorption edge fine structure is observed due to backscattering of the emitted photoelectron. The post-edge region can be divided into two parts. The X-ray Absorption Near Edge Structure (XANES) which extends up to 50 eV of an absorption edge, the spectrum is interpreted in terms of the appropriate components of the local density of states, which would be expected to be sensitive to the valence state of the atom. The intensity, shape and location of the absorption edge features provide information on the valence state, electronic structure and coordination geometry of the absorbing atom.The Extended X-ray Absorption Fine Structure (EXAFS) region is dominated by the single scattering processes and extends up to 1000 eV above the edge and provides information on the radial distribution (coordination number, radial distance and type of neighboring atoms) around the central atom. The results on perovskite based and spinel ferrites systems will be presented, where valence state and cation distributions are determined; the present study will show focus on SrFeO/sub 3/, MnFe/sub 2/O/sub 4/ and Zn/sub 1-x/Ni/sub x/Fe/sub 2/O/sub 4/ materials. (author)

X-Band Linac Beam-Line for Medical Compton Scattering X-Ray Source

CERN Document Server

Dobashi, Katsuhiro; Ebina, Futaro; Fukasawa, Atsushi; Hayano, Hitoshi; Higo, Toshiyasu; Kaneyasu, Tatsuo; Ogino, Haruyuki; Sakamoto, Fumito; Uesaka, Mitsuru; Urakawa, Junji; Yamamoto, Tomohiko

2005-01-01

Compton scattering hard X-ray source for 10~80 keV are under construction using the X-band (11.424 GHz) electron linear accelerator and YAG laser at Nuclear Engineering Research laboratory, University of Tokyo. This work is a part of the national project on the development of advanced compact medical accelerators in Japan. National Institute for Radiological Science is the host institute and U. Tokyo and KEK are working for the X-ray source. Main advantage is to produce tunable monochromatic hard ( 10-80

Physics Of, and Science With, the X-Ray Free-Electron Laser: 19th Advanced ICFA Beam Dynamics Workshop

International Nuclear Information System (INIS)

Sutton, M.

2003-01-01

The workshop brought together scientists working on the development of x-ray free-electron lasers, and its applications. X-ray free-electron lasers produce high intensity, subpicosecond long, coherent, X-ray pulses, and will open a new frontier to study the structure of matter at the molecular and atomic levels. Some fields of interest are structural changes in chemical reactions, single biological molecule, warm plasmas, nanosystems. Summary of discussions and conclusions of Group 1: Physics and Technology of the XFEL - The main issues that were discussed by the 50 participants in this group were the photo-injector, the production of ultra-short pulses, the effects of wake-fields induced by the electron bunch, the operation at lower charge and emittance, the possibility of harmonic generation and the diagnostics in the undulator. The following is a short summary of the discussions and their conclusions. Summary of discussions and conclusions of Group 2: Science with the XFEL - About 25 people attended sessions to discuss the possible scientific applications of a x-ray FEL. Because of the recent focus on the first experiments with the proposed Linac Coherent Light Source at Stanford, the discussions were mainly focussed on these proposals. The extension of the characteristics beyond the initial stage and the further developments of the source were also part of the program. Six scientific areas were discussed: Atomic Physics, Warm Dense Matter, Femtosecond Chemistry, Imaging/Holography, Bio-molecular Structures and X-Ray Fluctuations Spectroscopy.

eScience and archiving for space science

Directory of Open Access Journals (Sweden)

Timothy E Eastman

2006-01-01

Full Text Available A confluence of technologies is leading towards revolutionary new interactions between robust data sets, state-of-the-art models and simulations, high-data-rate sensors, and high-performance computing. Data and data systems are central to these new developments in various forms of eScience or grid systems. Space science missions are developing multi-spacecraft, distributed, communications- and computation-intensive, adaptive mission architectures that will further add to the data avalanche. Fortunately, Knowledge Discovery in Database (KDD tools are rapidly expanding to meet the need for more efficient information extraction and knowledge generation in this data-intensive environment. Concurrently, scientific data management is being augmented by content-based metadata and semantic services. Archiving, eScience and KDD all require a solid foundation in interoperability and systems architecture. These concepts are illustrated through examples of space science data preservation, archiving, and access, including application of the ISO-standard Open Archive Information System (OAIS architecture.

The Imaging X-Ray Polarimetry Explorer (IXPE): Overview

Science.gov (United States)

O'Dell, Steve; Weisskopf, M.; Soffitta, P.; Baldini, L.; Bellazzini, R.; Costa, E.; Elsner, R.; Kaspi, V.; Kolodziejczak, J.; Latronico, L.;

Ultrafast phenomena at the nanoscale: science opportunities at the SwissFEL X-ray laser

International Nuclear Information System (INIS)

Abela, R.; Braun, H.; Ming, P.; Pedrozzi, M.; Quitmann, Ch.; Reiche, S.; Daalen, M. van; Veen, J.F. van der; Mesot, J.; Mesot, J.; Shiroka, T.; Veen, J.F. van der; Mesot, J.

2009-09-01

In today's fast-moving society, standing still is effectively synonymous with being left behind. If it is to maintain, beyond the coming 10-15 years, its high international standing as a complex of large research infrastructures, the Paul Scherrer Institute (PSI) must now lay the foundation for a competitive future. Experts worldwide foresee a strongly growing demand within science and technology for photon sources delivering ultra-short, coherent X-ray pulses. Such a source, called a free electron laser (FEL), is nothing less than a gigantic flash camera, allowing us to take a deeper look into matter than with any other machine before. By literally seeing molecules in action, scientists will be able not only to capture chemical and biological processes of direct relevance and benefit to society but also to improve them. It is a dream coming true. For the first time, it will not only be possible to take pictures of molecular structures, we will be able to make movies of their motion. The new X-ray laser project at PSI, known as SwissFEL, will be an important addition to the existing complex of PSI facilities that serve interdisciplinary and international research teams from academia and industry. The SwissFEL is an essential element of Switzerland's strategic focus and will prolong our nation's leading position in scientific research for years to come. It will attract top scientists from Switzerland and abroad, and will strengthen the position of PSI as a world-class research institute. This new high-tech facility will also provide an important incentive for Swiss industry, through which existing highly-qualified jobs will be maintained and new ones created. In this report we present a wide range of important, open questions within science and engineering disciplines that SwissFEL will contribute towards solving. These questions, which form the 'scientific case' for SwissFEL, have been identified through a range of workshops organized over the past few years and by

The Synthetic Aperture Radar Science Data Processing Foundry Concept for Earth Science

Science.gov (United States)

Rosen, P. A.; Hua, H.; Norton, C. D.; Little, M. M.

2015-12-01

Since 2008, NASA's Earth Science Technology Office and the Advanced Information Systems Technology Program have invested in two technology evolutions to meet the needs of the community of scientists exploiting the rapidly growing database of international synthetic aperture radar (SAR) data. JPL, working with the science community, has developed the InSAR Scientific Computing Environment (ISCE), a next-generation interferometric SAR processing system that is designed to be flexible and extensible. ISCE currently supports many international space borne data sets but has been primarily focused on geodetic science and applications. A second evolutionary path, the Advanced Rapid Imaging and Analysis (ARIA) science data system, uses ISCE as its core science data processing engine and produces automated science and response products, quality assessments and metadata. The success of this two-front effort has been demonstrated in NASA's ability to respond to recent events with useful disaster support. JPL has enabled high-volume and low latency data production by the re-use of the hybrid cloud computing science data system (HySDS) that runs ARIA, leveraging on-premise cloud computing assets that are able to burst onto the Amazon Web Services (AWS) services as needed. Beyond geodetic applications, needs have emerged to process large volumes of time-series SAR data collected for estimation of biomass and its change, in such campaigns as the upcoming AfriSAR field campaign. ESTO is funding JPL to extend the ISCE-ARIA model to a "SAR Science Data Processing Foundry" to on-ramp new data sources and to produce new science data products to meet the needs of science teams and, in general, science community members. An extension of the ISCE-ARIA model to support on-demand processing will permit PIs to leverage this Foundry to produce data products from accepted data sources when they need them. This paper will describe each of the elements of the SAR SDP Foundry and describe their

Human genome sequencing with direct x-ray holographic imaging

International Nuclear Information System (INIS)

Rhodes, C.K.

1993-01-01

Direct holographic imaging of biological materials is widely applicable to the study of the structure, properties and action of genetic material. This particular application involves the sequencing of the human genome where prospective genomic imaging technology is composed of three subtechnologies, name an x-ray holographic camera, suitable chemistry and enzymology for the preparation of tagged DNA samples, and the illuminator in the form of an x-ray laser. We report appropriate x-ray camera, embodied by the instrument developed by MCR, is available and that suitable chemical and enzymatic procedures exist for the preparation of the necessary tagged DNA strands. Concerning the future development of the x-ray illuminator. We find that a practical small scale x-ray light source is indeed feasible. This outcome requires the use of unconventional physical processes in order to achieve the necessary power-compression in the amplifying medium. The understanding of these new physical mechanisms is developing rapidly. Importantly, although the x-ray source does not currently exist, the understanding of these new physical mechanisms is developing rapidly and the research has established the basic scaling laws that will determine the properties of the x-ray illuminator. When this x-ray source becomes available, an extremely rapid and cost effective instrument for 3-D imaging of biological materials can be applied to a wide range of biological structural assays, including the base-pair sequencing of the human genome and many questions regarding its higher levels of organization

Monitoring Inter- and Intra-Seasonal Dynamics of Rapidly Degrading Ice-Rich Permafrost Riverbanks in the Lena Delta with TerraSAR-X Time Series

Directory of Open Access Journals (Sweden)

Samuel Stettner

2017-12-01

Full Text Available Arctic warming is leading to substantial changes to permafrost including rapid degradation of ice and ice-rich coasts and riverbanks. In this study, we present and evaluate a high spatiotemporal resolution three-year time series of X-Band microwave satellite data from the TerraSAR-X (TSX satellite to quantify cliff-top erosion (CTE of an ice-rich permafrost riverbank in the central Lena Delta. We apply a threshold on TSX backscatter images and automatically extract cliff-top lines to derive intra- and inter-annual CTE. In order to examine the drivers of erosion we statistically compare CTE with climatic baseline data using linear mixed models and analysis of variance (ANOVA. Our evaluation of TSX-derived CTE against annual optical-derived CTE and seasonal in situ measurements showed good agreement between all three datasets. We observed continuous erosion from June to September in 2014 and 2015 with no significant seasonality across the thawing season. We found the highest net annual cliff-top erosion of 6.9 m in 2014, in accordance with above-average mean temperatures and thawing degree days as well as low precipitation. We found high net annual erosion and erosion variability in 2015 associated with moderate mean temperatures but above average precipitation. According to linear mixed models, climate parameters alone could not explain intra-seasonal erosional patterns and additional factors such as ground ice content likely drive the observed erosion. Finally, mean backscatter intensity on the cliff surface decreased from −5.29 to −6.69 dB from 2013 to 2015, respectively, likely resulting from changes in surface geometry and properties that could be connected to partial slope stabilization. Overall, we conclude that X-Band backscatter time series can successfully be used to complement optical remote sensing and in situ monitoring of rapid tundra permafrost erosion at riverbanks and coasts by reliably providing information about intra

The 100th Anniversary of X-Ray Crystallography

Directory of Open Access Journals (Sweden)

Kojić-Prodić, B.

2013-07-01

Full Text Available The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.W. L. BraggThe 100th anniversary of X-ray crystallography dates back to the first X-ray diffraction experiment on a crystal of copper sulphate pentahydrate. Max von Laue designed the theoretical background of the experiment, which was performed by German physicists W. Friedrich and P. Knipping in 1912. At that time, the mathematical formulation of the phenomenon and the fundamental concepts of crystallography were subjects of mineralogy. Altogether, they facilitated the development of methods for determination of the structure of matter at the atomic level. In 1913, father and son Bragg started to develop X-ray structure analysis for determination of crystal structures of simple molecules. Historic examples of structure determination starting from rock salt to complex, biologically important (macromolecules, such as globular proteins haemoglobin and myoglobin, DNA, vitamin B12 and the recent discovery of ribozyme, illustrate the development of X-ray structural analysis. The determination of 3D structures of these molecules by X-ray diffraction had opened new areas of scientific research, such as molecular biophysics, molecular genetics, structural molecular biology, bioinorganic chemistry, organometallic chemistry, and many others. The discovery and development of X-ray crystallography revolutionised our understanding of natural sciences – physics, chemistry, biology, and also science of materials. The scientific community recognised these fundamental achievements (including the discovery of X-rays by awarding twenty-eight Nobel prizes to thirty-nine men and two women. The explosive growth of science and technology in the 20th and 21st centuries had been founded on the detailed knowledge of the three-dimensional structure of molecules, which was the basis for explaining and predicting the physical, chemical, biological and

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

Directory of Open Access Journals (Sweden)

Marie-Christine Zdora

2018-04-01

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

Examining the Nexus of Science Communication and Science Education: A Content Analysis of Genetics News Articles

Science.gov (United States)

Shea, Nicole A.

2015-01-01

Access to science information via communications in the media is rapidly becoming a central means for the public to gain knowledge about scientific advancements. However, little is known about what content knowledge is essential for understanding issues presented in news media. Very few empirical studies attempt to bridge science communication and…

Understanding rapid theoretical change in particle physics: a month-by-month co-citation analysis

International Nuclear Information System (INIS)

Sullivan, D.; Koester, D.; White, D.H.; Kern, R.

1979-01-01

While co-citation analysis has proved a powerful tool in the study of changes in intellectual foci in science, no one has ever used the technique to study very rapid changes in the theoretical structure of a scientific field. This paper presents month-by-month co-citation analyses of key phases in the weak-electromagnetic unification research program within particle physics, and shows that these analyses capture and illuminate very rapid intellectual changes. These data provide yet another illustration of the utility of co-citation analysis for understanding the history of science. 8 figures

Secrets of Science. Videos 1-13. [Videotape.

Science.gov (United States)

Walt Disney Publishing Group, Burbank, CA. Discover Magazine.

Discoveries in science and technology are being made at such a rapid pace that it is often difficult for many teachers to stay abreast of new and relevant information. To assist teachers in keeping their students well informed of new discoveries in science, Discover Magazine developed a 13-part video series entitled "Secrets of Science." In each…

A metastable Mg11Sm phase obtained by rapid solidification

International Nuclear Information System (INIS)

Budurov, S.

1993-01-01

Molten Mg-Sm alloys with a Sm concentration of 4.93, 6.86, and 8.35 at.% were rapidly soldified with the aid of a shock wave gun device. Investigations of the obtained splats were performed with the aid of DSC, X-ray analysis, and metallography. Rapid soldification of the eutectic MgSm 8.35 alloy forms a new Im3m-type phase. (orig.)

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

The rapid heating effects on the microstructure, texture and magnetic properties of 3% Si nonoriented electrical steel has been investigated through optical microscopy, X-ray diffraction and Epstein frame. The results show that recrystallized grains were refined with increased heating rate, caused by the nucleation rate ...

The Athena X-ray Integral Field Unit (X-IFU)

Science.gov (United States)

Barret, Didier; Trong, Thein Lam; Den Herder, Jan-Willem; Piro, Luigi; Barcons, Xavier; Huovelin, Juhani; Kelley, Richard; Mas-Hesse, J. Miquel; Mitsuda, Kazuhisa; Paltani, Stephane;

Quaternary selenostannates Na{sub 2-x}Ga{sub 2-x}Sn{sub 1+x}Se{sub 6} and AGaSnSe{sub 4} (A=K, Rb, and Cs) through rapid cooling of melts. Kinetics versus thermodynamics in the polymorphism of AGaSnSe{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Hwang, S -J; Iyer, R G; Kanatzidis, M G

2004-10-01

The quaternary alkali-metal gallium selenostannates, Na{sub 2-x}Ga{sub 2-x}Sn{sub 1+x}Se{sub 6} and AGaSnSe{sub 4} (A=K, Rb, and Cs), were synthesized by reacting alkali-metal selenide, Ga, Sn, and Se with a flame melting-rapid cooling method. Na{sub 2-x}Ga{sub 2-x}Sn{sub 1+x}Se{sub 6} crystallizes in the non-centrosymmetric space group C2 with cell constants a=13.308(3) A, b=7.594(2) A, c=13.842(3) A, {beta}=118.730(4) deg., V=1226.7(5) A{sup 3}. {alpha}-KGaSnSe{sub 4} crystallizes in the tetragonal space group I4/mcm with a=8.186(5) A and c=6.403(5) A, V=429.1(5) A{sup 3}. {beta}-KGaSnSe{sub 4} crystallizes in the space group P2{sub 1}/c with cell constants a=7.490(2) A, b=12.578(3) A, c=18.306(5) A, {beta}=98.653(5) deg., V=1705.0(8) A{sup 3}. The unit cell of isostructural RbGaSnSe{sub 4} is a=7.567(2) A, b=12.656(3) A, c=18.277(4) A, {beta}=95.924(4) deg., V=1741.1(7) A{sup 3}. CsGaSnSe{sub 4} crystallizes in the orthorhombic space group Pmcn with a=7.679(2) A, b=12.655(3) A, c=18.278(5) A, V=1776.1(8) A{sup 3}. The structure of Na{sub 2-x}Ga{sub 2-x}Sn{sub 1+x}Se{sub 6} consists of a polar three-dimensional network of trimeric (Sn,Ga){sub 3}Se{sub 9} units with Na atoms located in tunnels. The AGaSnSe{sub 4} possess layered structures. The compounds show nearly the same Raman spectral features, except for Na{sub 2-x}Ga{sub 2-x}Sn{sub 1+x}Se{sub 6}. Optical band gaps, determined from UV-Vis spectroscopy, range from 1.50 eV in Na{sub 2-x}Ga{sub 2-x}Sn{sub 1+x}Se{sub 6} to 1.97 eV in CsGaSnSe{sub 4}. Cooling of the melts of KGaSnSe{sub 4} and RbGaSnSe{sub 4} produces only kinetically stable products. The thermodynamically stable product is accessible under extended annealing, which leads to the so-called {gamma}-form (BaGa{sub 2}S{sub 4}-type) of these compounds.

X-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Ray, N.B.

1977-01-01

The principle, instrument and procedure of X-ray fluorescence spectrometry are described. It is a rapid, simple and sensitive method for the trace analysis of elements from sodium to uranium in powder, liquid or metal samples. (M.G.B.)

A New Instrument for the IRTF: the MIT Optical Rapid Imaging System (MORIS)

Science.gov (United States)

Gulbis, Amanda A. S.; Elliot, J. L.; Rojas, F. E.; Bus, S. J.; Rayner, J. T.; Stahlberger, W. E.; Tokunaga, A. T.; Adams, E. R.; Person, M. J.

2010-10-01

NASA's 3-m Infrared Telescope Facility (IRTF) on Mauna Kea, HI plays a leading role in obtaining planetary science observations. However, there has been no capability for high-speed, visible imaging from this telescope. Here we present a new IRTF instrument, MORIS, the MIT Optical Rapid Imaging System. MORIS is based on POETS (Portable Occultation Eclipse and Transit Systems; Souza et al., 2006, PASP, 118, 1550). Its primary component is an Andor iXon camera, a 512x512 array of 16-micron pixels with high quantum efficiency, low read noise, low dark current, and full-frame readout rates of between 3.5 Hz (6 e /pixel read noise) and 35 Hz (49 e /pixel read noise at electron-multiplying gain=1). User-selectable binning and subframing can increase the cadence to a few hundred Hz. An electron-multiplying mode can be employed for photon counting, effectively reducing the read noise to sub-electron levels at the expense of dynamic range. Data cubes, or individual frames, can be triggered to nanosecond accuracy using a GPS. MORIS is mounted on the side-facing widow of SpeX (Rayner et al. 2003, PASP, 115, 362), allowing simultaneous near-infrared and visible observations. The mounting box contains 3:1 reducing optics to produce a 60 arcsec x 60 arcsec field of view at f/12.7. It hosts a ten-slot filter wheel, with Sloan g×, r×, i×, and z×, VR, Johnson V, and long-pass red filters. We describe the instrument design, components, and measured characteristics. We report results from the first science observations, a 24 June 2008 stellar occultation by Pluto. We also discuss a recent overhaul of the optical path, performed in order to eliminate scattered light. This work is supported in part by NASA Planetary Major Equipment grant NNX07AK95G. We are indebted to the University of Hawai'i Institute for Astronomy machine shop, in particular Randy Chung, for fabricating instrument components.

A Simbol-X Event Simulator

International Nuclear Information System (INIS)

Puccetti, S.; Giommi, P.; Fiore, F.

2009-01-01

The ASI Science Data Center (ASDC) has developed an X-ray event simulator to support users (and team members) in simulation of data taken with the two cameras on board the Simbol-X X-Ray Telescope. The Simbol-X simulator is very fast and flexible, compared to ray-tracing simulator. These properties make our simulator advantageous to support the user in planning proposals and comparing real data with the theoretical expectations and for a quick detection of unexpected features. We present here the simulator outline and a few examples of simulated data.

A Simbol-X Event Simulator

Science.gov (United States)

Puccetti, S.; Fiore, F.; Giommi, P.

2009-05-01

The ASI Science Data Center (ASDC) has developed an X-ray event simulator to support users (and team members) in simulation of data taken with the two cameras on board the Simbol-X X-Ray Telescope. The Simbol-X simulator is very fast and flexible, compared to ray-tracing simulator. These properties make our simulator advantageous to support the user in planning proposals and comparing real data with the theoretical expectations and for a quick detection of unexpected features. We present here the simulator outline and a few examples of simulated data.

MapX An In Situ, Full-frame X-Ray Spectroscopic Imager for Planetary Science and Astrobiology

Science.gov (United States)

Blake, David; Sarrazin, Philippe; Thompson, Kathleen; Bristow, Thomas

2017-01-01

Microbial life exploits micron-scale disequilibria at boundaries where valence, chemical potential, pH, Eh, etc. vary on a length scale commensurate with the organisms - 10's to 100's of microns. The detection of accumulations of the biogenic elements C,N,O,P,S at appropriate concentrations on or in a mineral/ice substrate would constitute permissive evidence of extant life, but context is also required. Does the putative biosignature exist under habitable conditions? Under what conditions of P, T, and chemical potential was the host mineralogy formed? MapX is an in situ robotic spacecraft instrument that images the biogenic elements C, N, O, P, S, as well as the cations of the rock-forming minerals (Na, Mg, Al, Si, K, Ca, Ti, Cr, Mn, Fe) and important anions such as Cl, Fl. MapX provides element maps with less than or equal to100 microns resolution over a 2.5 cm X 2.5 cm area, as well as quantitative XRF spectra from ground- or instrument-selected Regions of Interest (ROI). XRF spectra are converted to mineralogies using ground- or instrument-based algorithms. Either X-ray tube or radioisotope sources such as 244Cm (Alpha-particle and gamma- ray fluorescence) can be used. Fluoresced sample Xrays are imaged onto an X-ray sensitive CCD through an X-ray MicroPore Optic (MPO). The MapX design as well as baseline performance requirements for a MapX instrument intended for life detection / identification of habitable environments will be presented.

Semiconductor X-ray detectors

CERN Document Server

Lowe, Barrie Glyn

2014-01-01

Identifying and measuring the elemental x-rays released when materials are examined with particles (electrons, protons, alpha particles, etc.) or photons (x-rays and gamma rays) is still considered to be the primary analytical technique for routine and non-destructive materials analysis. The Lithium Drifted Silicon (Si(Li)) X-Ray Detector, with its good resolution and peak to background, pioneered this type of analysis on electron microscopes, x-ray fluorescence instruments, and radioactive source- and accelerator-based excitation systems. Although rapid progress in Silicon Drift Detectors (SDDs), Charge Coupled Devices (CCDs), and Compound Semiconductor Detectors, including renewed interest in alternative materials such as CdZnTe and diamond, has made the Si(Li) X-Ray Detector nearly obsolete, the device serves as a useful benchmark and still is used in special instances where its large, sensitive depth is essential. Semiconductor X-Ray Detectors focuses on the history and development of Si(Li) X-Ray Detect...

X-Ray Lasers 2016

CERN Document Server

Bulanov, Sergei; Daido, Hiroyuki; Kato, Yoshiaki

2018-01-01

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

Measurement and Analysis of Composition and Depth Profile of H in Amorphous Si1−xCx:H Films

International Nuclear Information System (INIS)

Wei, Hua; Shu-De, Yao; Kun, Wang; Zhi-Bo, Ding

2008-01-01

Composition in amorphous Si 1−X C x :H heteroepitaxial thin films on Si (100) by plasma enhanced chemical vapour deposition (PECVD) is analysed. The unknown x (0.45–0.57) and the depth profile of hydrogen in the thin films are characterized by Rutherford backscattering spectrum (RBS), resonance-nuclear reaction analysis (R-NRA) and elastic recoil detection (ERD), respectively. In addition, the depth profile of hydrogen in the unannealed thin films is compared to that of the annealed thin films with rapid thermal annealing (RTA) or laser spike annealing (LSA) in nitrogen atmosphere. The results indicate that the stoichiometric amorphous SiC can be produced by PECVD when the ratio of CH 4 /SiH 4 is approximately equal to 25. The content of hydrogen decreases suddenly from 35% to 1% after 1150° C annealing. RTA can reduce hydrogen in SiC films effectively than LSA. (cross-disciplinary physics and related areas of science and technology)

Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis

International Nuclear Information System (INIS)

Chen, J.R.; Gordon, B.M.; Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Chao, E.C.T.; Minkin, J.A.

1984-01-01

The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of synchrotron radiation include experiments in synchrotron x-ray fluorescence (SXRF) analysis and extended x-ray absorption fine structure (EXAFS) analysis. New synchrotron radiation x-ray microprobes for elemental analysis in the parts per billion range are under construction at several laboratories. 76 references, 24 figures

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 129; Issue 2 ... Rapid Communication Volume 129 Issue 2 February 2017 pp 149-156 ... The central perylene core of 1 is twisted with dihedral angles of 19.48(2)◦ and 19.50(2)◦; this twist configuration induces the axial chirality in this family of perylene bisimide ...

Effect of Si substitution on structural, electronic and optical properties of YNi{sub 4}Si-type DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) compounds

Energy Technology Data Exchange (ETDEWEB)

Maurya, Dinesh Kumar; Saini, Sapan Mohan, E-mail: smsaini.phy@nitrr.ac.in

2016-10-15

We employed first principle calculations for investigation of structural, electronic and optical properties of YNi{sub 4}Si-type DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) compounds. These properties are studied first time on YNi{sub 4}Si-type DyNi{sub 5−x}Si{sub x} compounds. The exchange and correlation potential is treated by the Coulomb corrected local spin density approximation (LSDA+U) method for better accounting of the correlation between the 4f electrons. The optimized lattice constants and internal cell parameters are in agreement with the available data. Self consistence band structure calculations show that Ni-3d states remains in valance band and dominant below the E{sub F}, while Dy-5d and 4f states mainly contributes above Fermi Energy (E{sub F}) in DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) compounds. We also find that when silicon for nickel substitution takes place (DyNi{sub 4}Si), there is a gradual hybridization of Ni-3d and Si-3p states results, nickel moments decrease rapidly in agreement with the experiment. Optical spectra shows the main absorption peak around 4 eV depends on the substituent concentration and could be due to transition from hybridized band (Ni-3d and Si-3p), below E{sub F} to free Dy-4d states. Frequency-dependent refractive index, n(ω), and the extinction coefficient, k(ω), of DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) are also calculated for the radiation up to 14 eV. - Highlights: • Calculated DOS revels that Ni-3d states are dominated below Fermi level (E{sub F}). • Spin down Dy-4f states show significant contribution to DOS above E{sub F.} • Nickel moments decrease rapidly with substitution of silicon for nickel (DyNi{sub 4}Si). • Most significant peak is found around 7eV in optical conductivity. • Nickel moments decrease rapidly with substitution of silicon for nickel (DyNi{sub 4}Si). • Peak indicates the possibility of transitions from Ni-3d states to empty spin down Dy-4f states.

Science Resulting from U.S. Geological Survey's "Did You Feel It?" Citizen Science Portal

Science.gov (United States)

Wald, D. J.; Dewey, J. W.; Atkinson, G. M.; Worden, C. B.; Quitoriano, V. P. R.

2016-12-01

The U.S. Geological Survey (USGS) "Did You Feel It?" (DYFI) system, in operation since 1999, is an automated approach for rapidly collecting macroseismic intensity data from internet users' shaking and damage reports and generating intensity maps immediately following earthquakes felt around the globe. As with any citizen science project, a significant component of the DYFI system is public awareness and participation in the immediate aftermath of any widely felt earthquake, allowing the public and the USGS to exchange valuable post-earthquake information. The data collected are remarkably robust and useful, as indicated by the range of peer-reviewed literature that rely on these citizen-science intensity reports. A Google Scholar search results in 14,700 articles citing DYFI, a number of which rely exclusively on these data. Though focused on topics of earthquake seismology (including shaking attenuation and relationships with damage), other studies cover social media use in disasters, human risk perception, earthquake-induced landslides, rapid impact assessment, emergency response, and science education. DYFI data have also been analyzed for non-earthquake events, including explosions, aircraft sonic booms, and even bolides and DYFI is now one of the best data sources from which to study induced earthquakes. Yet, DYFI was designed primarily as an operational system to rapidly assess the effects of earthquakes for situational awareness. Oftentimes, DYFI data are the only data available pertaining to shaking levels for much of the United States. As such, DYFI provides site-specific constraints of the shaking levels that feed directly into ShakeMap; thus, these data are readily available to emergency managers and responders, the media, and the general public. As an early adopter of web-based citizen science and having worked out many kinks in the process, DYFI developers have provided guidance on many other citizen-science endeavors across a wide range of

The STAR-X X-Ray Telescope Assembly (XTA)

Science.gov (United States)

McClelland, Ryan S.; Bautz, Mark W.; Bonafede, Joseph A.; Miller, Eric D.; Saha, Timo T.; Solly, Peter M.; Zhang, William W.

2017-01-01

The Survey and Time-domain Astrophysical Research eXplorer (STAR-X) science goals are to discover what powers the most violent explosions in the Universe, understand how black holes grow across cosmic time and mass scale, and measure how structure formation heats the majority of baryons in the Universe. To achieve these goals, STAR-X requires a powerful X-ray telescope with a large field of view, large collecting area, and excellent point spread function. The STAR-X instrument, the X-Ray Telescope Assembly (XTA), meets these requirements using a powerful X-ray mirror technology based on precision-polished single crystal silicon and a mature CCD detector technology. The XTA is composed of three major subsystems: an X-ray Mirror Assembly (MA) of high resolution, lightweight mirror segments fabricated out of single crystal silicon; a Focal Plane Assembly (FPA) made of back-illuminated CCD's capable of detecting X-rays with excellent quantum efficiency; and a composite Telescope Tube that structurally links the MA and FPA. The MA consists of 5,972 silicon mirror segments mounted into five subassemblies called meta-shells. A meta-shell is constructed from an annular central structural shell covered with interlocking layers of mirror segments. This paper describes the requirements, design, and analysis of the XTA subsystems with particular focus on the MA.

Thin Mirror Shaping Technology for High-Throughput X-ray Telescopes

Science.gov (United States)

Schattenburg, Mark

This proposal is submitted to the NASA Research Opportunities in Space and Earth Sciences program (ROSES-2012) in response to NASA Research Announcement NNH12ZDA001N- APRA. It is targeted to the Astronomy and Astrophysics Research and Analysis (APRA) program element under the Supporting Technology category. Powerful x-ray telescope mirrors are critical components of a raft of small-to-large mission concepts under consideration by NASA. The science questions addressed by these missions have certainly never been more compelling and the need to fulfill NASA s core missions of exploring the universe and strengthening our nation s technology base has never been greater. Unfortunately, budgetary constraints are driving NASA to consider the cost/benefit and risk factors of new missions more carefully than ever. New technology for producing x-ray telescopes with increased resolution and collecting area, while holding down cost, are key to meeting these goals and sustaining a thriving high-energy astrophysics enterprise in the US. We propose to develop advanced technology which will lead to thin-shell x-ray telescope mirrors rivaling the Chandra x-ray telescope in spatial resolution but with 10-100X larger area all at significantly reduced weight, risk and cost. The proposed effort builds on previous research at MIT and complements NASA-supported research at other institutions. We are currently pursuing two thin-mirror technology development tracks which we propose to extend and accelerate with NASA support. The first research track utilizes rapidly-maturing thermal glass slumping technology which uses porous ceramic air-bearing mandrels to shape glass mirrors without touching, thus avoiding surface-induced mid-range spatial frequency ripples. A second research track seeks to remove any remaining mid- to long-range errors in mirrors by using scanning ion-beam implant to impart small, highly deterministic and very stable amounts of stress into thin glass, utilizing local

Ag screen contacts to sintered YBa/sub 2/Cu/sub 3/O/sub x/ powder for rapid superconductor characterization

International Nuclear Information System (INIS)

Moreland, J.; Goodrich, L.F.

1989-01-01

The authors have developed a new method for making current contacts and voltage taps to YBa/sub 2/Cu/sub 3/O/sub x/ sintered pellets for rapid superconductor characterization. Ag wire screens are interleaved between calcined powder sections and then fired at 930 0 C to form a composite pellet for resistivity and critical current measurements. The Ag diffuses into the powder during the sintering process forming a proximity contact that is permeable to O/sub 2/. Contact surface resistivities (area-resistance product) range from 1 to 10μΩ-cm/sup 2/ at 77 K for the Ag-powder interface. In this configuration, current can be uniformly injected into the ends of the pellet through the bonded Ag screen electrodes. Also, Ag screen voltage contacts, which span a cross section of the pellet, may provide an ideal geometry for detecting voltage drops along the pellet, minimizing current transfer effects

Cupriavidus necator JMP134 rapidly reduces furfural with a Zn-dependent alcohol dehydrogenase.

Science.gov (United States)

Li, Qunrui; Metthew Lam, L K; Xun, Luying

2011-11-01

Ethanol is a renewable biofuel, and it can be produced from lignocellulosic biomass. The biomass is usually converted to hydrolysates that consist of sugar and sugar derivatives, such as furfural. Yeast ferments sugar to ethanol, but furfural higher than 3 mM is inhibitory. It can take several days for yeast cells to reduce furfural to non-inhibitory furfuryl alcohol before producing ethanol. Bioreduction of furfural to furfuryl alcohol before fermentation may relieve yeast from furfural toxicity. We observed that Cupriavidus necator JMP134, a strict aerobe, rapidly reduced 17 mM furfural to less than 3 mM within 14 min with cell turbidity of 1.0 at 600 nm at 50°C. The rapid reduction consumed ethanol. The "furfural reductase" (FurX) was purified, and it oxidized ethanol to acetaldehyde and reduced furfural to furfuryl alcohol with NAD(+) as the cofactor. The protein was identified with mass spectrometry fingerprinting to be a hypothetical protein belonging to Zn-dependent alcohol dehydrogenase family. The furX-inactivation mutant of C. necator JMP134 lost the ability to rapidly reduce furfural, and Escherichia coli producing recombinant FurX gained the ability. Thus, an alcohol dehydrogenase enabled bacteria to rapidly reduce furfural with ethanol as the reducing power.

The Scientific Theory Profile: A Philosophy of Science Model for Science Teachers.

Science.gov (United States)

Loving, Cathleen

The model developed for use with science teachers--called the Scientific Theory Profile--consists of placing three well-known philosophers of science on a grid, with the x-axis being their methods for judging theories (rational vs. natural) and the y-axis being their views on scientific theories representing the Truth versus mere models of what…

X-ray Crystallography of Biological Macromolecules -RE ...

Indian Academy of Sciences (India)

trons of the atoms scatter X-rays and if identical molecules are arranged in a ... Institute of Science,. Bangalore. ... The first X-ray diffraction pictures were taken and the theory .... various processes involved in biological systems in detail. We.

A New High-sensitivity solar X-ray Spectrophotometer SphinX:early operations and databases

Science.gov (United States)

Gburek, Szymon; Sylwester, Janusz; Kowalinski, Miroslaw; Siarkowski, Marek; Bakala, Jaroslaw; Podgorski, Piotr; Trzebinski, Witold; Plocieniak, Stefan; Kordylewski, Zbigniew; Kuzin, Sergey; Farnik, Frantisek; Reale, Fabio

The Solar Photometer in X-rays (SphinX) is an instrument operating aboard Russian CORONAS-Photon satellite. A short description of this unique instrument will be presented and its unique capabilities discussed. SphinX is presently the most sensitive solar X-ray spectrophotometer measuring solar spectra in the energy range above 1 keV. A large archive of SphinX mea-surements has already been collected. General access to these measurements is possible. The SphinX data repositories contain lightcurves, spectra, and photon arrival time measurements. The SphinX data cover nearly continuously the period since the satellite launch on January 30, 2009 up to the end-of November 2009. Present instrument status, data formats and data access methods will be shown. An overview of possible new science coming from SphinX data analysis will be discussed.

Exploring transient X-ray sky with Einstein Probe

Science.gov (United States)

Yuan, W.; Zhang, C.; Ling, Z.; Zhao, D.; Chen, Y.; Lu, F.; Zhang, S.

2017-10-01

The Einstein Probe is a small satellite in time-domain astronomy to monitor the soft X-ray sky. It is a small mission in the space science programme of the Chinese Academy of Sciences. It will carry out systematic survey and characterisation of high-energy transients at unprecedented sensitivity, spatial resolution, Grasp and monitoring cadence. Its wide-field imaging capability is achieved by using established technology of micro-pore lobster-eye X-ray focusing optics. Complementary to this is X-ray follow-up capability enabled by a narrow-field X-ray telescope. It is capable of on-board triggering and real time downlink of transient alerts, in order to trigger fast follow-up observations at multi-wavelengths. Its scientific goals are concerned with discovering and characterising diverse types of X-ray transients, including tidal disruption events, supernova shock breakouts, high-redshift GRBs, and of particular interest, X-ray counterparts of gravitational wave events.

Large-scale laser-microwave synchronization for attosecond photon science facilities

Energy Technology Data Exchange (ETDEWEB)

Shafak, Kemal

2017-04-15

Low-noise transfer of time and frequency standards over large distances provides high temporal resolution for ambitious scientific explorations such as sensitive imaging of astronomical objects using multi-telescope arrays, comparison of distant optical clocks or gravitational-wave detection using large laser interferometers. In particular, rapidly expanding photon science facilities such as X-ray free-electron lasers (FELs) and attoscience centers have the most challenging synchronization requirements of sub-fs timing precision to generate ultrashort X-ray pulses for the benefit of creating super-microscopes with sub-atomic spatiotemporal resolution. The critical task in these facilities is to synchronize various pulsed lasers and microwave sources across multi-kilometer distances as required for seeded FELs and attosecond pump-probe experiments. So far, there has been no timing distribution system meeting this strict requirement. Therefore, insufficient temporal precision provided by the current synchronization systems hinders the development of attosecond hard X-ray photon science facilities. The aim of this thesis is to devise a timing distribution system satisfying the most challenging synchronization requirements in science mandated by the next-generation photon science facilities. Using the pulsed-optical timing distribution approach, attosecond timing precision is realized by thoroughly investigating and eliminating the remaining noise sources in the synchronization system. First, optical and microwave timing detection schemes are further developed to support long-term stable, attosecond-precision measurements. Second, the feasibility of the master laser to support a kilometer-scale timing network with attosecond precision is examined by experimentally characterizing its free-running timing jitter and improving its long-term frequency stability with a sophisticated environmental insulation. Third, nonlinear pulse propagation inside optical fibers is studied

Large-scale laser-microwave synchronization for attosecond photon science facilities

International Nuclear Information System (INIS)

Shafak, Kemal

2017-04-01

Low-noise transfer of time and frequency standards over large distances provides high temporal resolution for ambitious scientific explorations such as sensitive imaging of astronomical objects using multi-telescope arrays, comparison of distant optical clocks or gravitational-wave detection using large laser interferometers. In particular, rapidly expanding photon science facilities such as X-ray free-electron lasers (FELs) and attoscience centers have the most challenging synchronization requirements of sub-fs timing precision to generate ultrashort X-ray pulses for the benefit of creating super-microscopes with sub-atomic spatiotemporal resolution. The critical task in these facilities is to synchronize various pulsed lasers and microwave sources across multi-kilometer distances as required for seeded FELs and attosecond pump-probe experiments. So far, there has been no timing distribution system meeting this strict requirement. Therefore, insufficient temporal precision provided by the current synchronization systems hinders the development of attosecond hard X-ray photon science facilities. The aim of this thesis is to devise a timing distribution system satisfying the most challenging synchronization requirements in science mandated by the next-generation photon science facilities. Using the pulsed-optical timing distribution approach, attosecond timing precision is realized by thoroughly investigating and eliminating the remaining noise sources in the synchronization system. First, optical and microwave timing detection schemes are further developed to support long-term stable, attosecond-precision measurements. Second, the feasibility of the master laser to support a kilometer-scale timing network with attosecond precision is examined by experimentally characterizing its free-running timing jitter and improving its long-term frequency stability with a sophisticated environmental insulation. Third, nonlinear pulse propagation inside optical fibers is studied

Ultrafast phenomena at the nanoscale: science opportunities at the SwissFEL X-ray laser

Energy Technology Data Exchange (ETDEWEB)

Abela, R.; Braun, H.; Ming, P.; Pedrozzi, M.; Quitmann, Ch.; Reiche, S.; Daalen, M. van; Veen, J.F. van der; Mesot, J. [Paul Scherrer Intitute (PSI), Villigen (Switzerland); Mesot, J.; Shiroka, T.; Veen, J.F. van der [Swiss Federal Institute of Technology (ETHZ), Zuerich (Switzerland); Mesot, J. [Swiss Federal Institute of Technology (EPFL), Lausanne (Switzerland)

2009-09-15

In today's fast-moving society, standing still is effectively synonymous with being left behind. If it is to maintain, beyond the coming 10-15 years, its high international standing as a complex of large research infrastructures, the Paul Scherrer Institute (PSI) must now lay the foundation for a competitive future. Experts worldwide foresee a strongly growing demand within science and technology for photon sources delivering ultra-short, coherent X-ray pulses. Such a source, called a free electron laser (FEL), is nothing less than a gigantic flash camera, allowing us to take a deeper look into matter than with any other machine before. By literally seeing molecules in action, scientists will be able not only to capture chemical and biological processes of direct relevance and benefit to society but also to improve them. It is a dream coming true. For the first time, it will not only be possible to take pictures of molecular structures, we will be able to make movies of their motion. The new X-ray laser project at PSI, known as SwissFEL, will be an important addition to the existing complex of PSI facilities that serve interdisciplinary and international research teams from academia and industry. The SwissFEL is an essential element of Switzerland's strategic focus and will prolong our nation's leading position in scientific research for years to come. It will attract top scientists from Switzerland and abroad, and will strengthen the position of PSI as a world-class research institute. This new high-tech facility will also provide an important incentive for Swiss industry, through which existing highly-qualified jobs will be maintained and new ones created. In this report we present a wide range of important, open questions within science and engineering disciplines that SwissFEL will contribute towards solving. These questions, which form the 'scientific case' for SwissFEL, have been identified through a range of workshops organized over

JINR rapid communications

International Nuclear Information System (INIS)

1995-01-01

The present collection of rapid communications from JINR, Dubna, contains eight separate reports on the measurement of charge radii for Ti nuclei, spectroscopy of 13 Be, concentrations of hadrons and quark-gluon plasma in mixed phase, experimental results on one-spin pion asymmetry in the d↑ + A → π±(90 0 ) + X process, new results on cumulative pion and proton production in p-D collisions, investigation of charge exchange reactions, the study of the tensor analyzing power in cumulative particle production on a deuteron beam and an evidence for the excited states of the S = -2 stable light dibaryon. 32 figs., 6 tabs

[Rapid determination of major and trace elements in the salt lake clay minerals by X-ray fluorescence spectrometry].

Science.gov (United States)

Wang, Xiao-Huan; Meng, Qing-Fen; Dong, Ya-Ping; Chen, Mei-Da; Li, Wu

2010-03-01

A rapid multi-element analysis method for clay mineral samples was described. This method utilized a polarized wave-length dispersive X-ray fluorescence spectrometer--Axios PW4400, which had a maximum tube power of 4 000 watts. The method was developed for the determination of As, Mn, Co, Cu, Cr, Dy, Ga, Mo, P, Pb, Rb, S, Sr, Ni, ,Cs, Ta, Th, Ti, U, V, Y, Zn, Zr, MgO, K2O, Na2O, CaO, Fe2O3, Al2O3, SiO2 and so on. Thirty elements in clay mineral species were measured by X-ray fluorescence spectrometry with pressed powder pellets. Spectral interferences, in particular the indirect interferences of each element, were studied. A method to distinguish the interference between each other periodic elements in element periodic table was put forward. The measuring conditions and existence were mainly investigated, and the selected background position as well as corrected spectral overlap for the trace elements were also discussed. It was found that the indirect spectral overlap line was the same important as direct spectral overlap line. Due to inducing the effect of indirect spectral overlap, some elements jlike Bi, Sn, W which do not need analysis were also added to the elements channel. The relative standard deviation (RSD) was in the range of 0.01% to 5.45% except three elements Mo, Cs and Ta. The detection limits, precisions and accuracies for most elements using this method can meet the requirements of sample analysis in clay mineral species.

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

International Nuclear Information System (INIS)

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

2003-01-01

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

Structural Investigation of Rapidly Quenched FeCoPtB Alloys

International Nuclear Information System (INIS)

Grabias, A.; Kopcewicz, M.; Latuch, J.; Oleszak, D.

2011-01-01

Two sets of Fe 52-x Co x Pt 28 B 20 (x = 0-26 at.%) and Fe 60-x Co x Pt 25 B 15 (x = 0-40 at.%) alloys were prepared in the form of ribbons by the rapid quenching technique. Structure of the samples was characterized by Moessbauer spectroscopy and X-ray diffraction. In the as-quenched alloys the amorphous phase coexisted with the fcc-(Fe,Co)Pt disordered solid solution. Differential scanning calorimetry measurements performed in the range 50-720 ± C revealed one or two exothermal peaks. The magnetically hard ordered L1 0 (Fe,Co)Pt and magnetically soft (Fe,Co) 2 B nanocrystalline phases were formed due to thermal treatment of the alloys. The influence of Co content on the structure of the as-quenched and heated alloys was studied. (authors)

Probing Photoinduced Structural Phase Transitions by Fast or Ultra-Fast Time-Resolved X-Ray Diffraction

Science.gov (United States)

Cailleau, Hervé Collet, Eric; Buron-Le Cointe, Marylise; Lemée-Cailleau, Marie-Hélène Koshihara, Shin-Ya

A new frontier in the field of structural science is the emergence of the fast and ultra-fast X-ray science. Recent developments in time-resolved X-ray diffraction promise direct access to the dynamics of electronic, atomic and molecular motions in condensed matter triggered by a pulsed laser irradiation, i.e. to record "molecular movies" during the transformation of matter initiated by light pulse. These laser pump and X-ray probe techniques now provide an outstanding opportunity for the direct observation of a photoinduced structural phase transition as it takes place. The use of X-ray short-pulse of about 100ps around third-generation synchrotron sources allows structural investigations of fast photoinduced processes. Other new X-ray sources, such as laser-produced plasma ones, generate ultra-short pulses down to 100 fs. This opens the way to femtosecond X-ray crystallography, but with rather low X-ray intensities and more limited experimental possibilities at present. However this new ultra-fast science rapidly progresses around these sources and new large-scale projects exist. It is the aim of this contribution to overview the state of art and the perspectives of fast and ultra-fast X-ray scattering techniques to study photoinduced phase transitions (here, the word ultra-fast is used for sub-picosecond time resolution). In particular we would like to largely present the contribution of crystallographic methods in comparison with optical methods, such as pump-probe reflectivity measurements, the reader being not necessary familiar with X-ray scattering. Thus we want to present which type of physical information can be obtained from the positions of the Bragg peaks, their intensity and their shape, as well as from the diffuse scattering beyond Bragg peaks. An important physical feature is to take into consideration the difference in nature between a photoinduced phase transition and conventional homogeneous photoinduced chemical or biochemical processes where

Featured Image: Making a Rapidly Rotating Black Hole

Science.gov (United States)

Kohler, Susanna

2017-10-01

These stills from a simulation show the evolution (from left to right and top to bottom) of a high-mass X-ray binary over 1.1 days, starting after the star on the right fails to explode as a supernova and then collapses into a black hole. Many high-mass X-ray binaries like the well-known Cygnus X-1, the first source widely accepted to be a black hole host rapidly spinning black holes. Despite our observations of these systems, however, were still not sure how these objects end up with such high rotation speeds. Using simulations like that shown above, a team of scientists led by Aldo Batta (UC Santa Cruz) has demonstrated how a failed supernova explosion can result in such a rapidly spinning black hole. The authors work shows that in a binary where one star attempts to explode as a supernova and fails it doesnt succeed in unbinding the star the large amount of fallback material can interact with the companion star and then accrete onto the black hole, spinning it up in the process. You can read more about the authors simulations and conclusions in the paper below.CitationAldo Batta et al 2017 ApJL 846 L15. doi:10.3847/2041-8213/aa8506

NASA MSFC Electrostatic Levitator (ESL) Rapid Quench System

Science.gov (United States)

SanSoucie, Michael P.; Craven, Paul D.

2014-01-01

Electrostatic levitation, a form of containerless processing, is an important tool in materials research. Levitated specimens are free from contact with a container; therefore, heterogeneous nucleation on container walls is not possible. This allows studies of deeply undercooled melts. Furthermore, studies of high-temperature, highly reactive materials are also possible. Studies of the solidification and crystallization of undercooled melts is vital to the understanding of microstructure development, particularly the formation of alloys with unique properties by rapid solidification. The NASA Marshall Space Flight Center (MSFC) Electrostatic Levitator (ESL) lab has recently been upgraded to allow for rapid quenching of levitated materials. The ESL Rapid Quench System uses a small crucible-like vessel that can be partially filled with a low melting point material, such as a Gallium alloy, as a quench medium. An undercooled sample can be dropped into the vessel to rapidly quench the sample. A carousel with nine vessels sits below the bottom electrode assembly. This system allows up to nine rapid quenches before having to break vacuum and remove the vessels. This new Rapid Quench System will allow materials science studies of undercooled materials and new materials development. In this presentation, the system is described and initial results are presented.

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 128; Issue 1. Synthesis, spectral properties and DNA binding and nuclease activity of lanthanide (III) complexes of 2-benzoylpyridine benzhydrazone: X-ray crystal structure, Hirshfeld studies and nitrate- interactions of cerium(III) complex. Karreddula Raja Akkili ...

Towards the development of rapid screening techniques for shale gas core properties

Science.gov (United States)

Cave, Mark R.; Vane, Christopher; Kemp, Simon; Harrington, Jon; Cuss, Robert

2013-04-01

Shale gas has been produced for many years in the U.S.A. and forms around 8% of total their natural gas production. Recent testing for gas on the Fylde Coast in Lancashire UK suggests there are potentially large reserves which could be exploited. The increasing significance of shale gas has lead to the need for deeper understanding of shale behaviour. There are many factors which govern whether a particular shale will become a shale gas resource and these include: i) Organic matter abundance, type and thermal maturity; ii) Porosity-permeability relationships and pore size distribution; iii) Brittleness and its relationship to mineralogy and rock fabric. Measurements of these properties require sophisticated and time consuming laboratory techniques (Josh et al 2012), whereas rapid screening techniques could provide timely results which could improve the efficiency and cost effectiveness of exploration. In this study, techniques which are portable and provide rapid on-site measurements (X-ray Fluorescence (XRF) and Infra-red (IR) spectroscopy) have been calibrated against standard laboratory techniques (Rock-Eval 6 analyser-Vinci Technologies) and Powder whole-rock XRD analysis was carried out using a PANalytical X'Pert Pro series diffractometer equipped with a cobalt-target tube, X'Celerator detector and operated at 45kV and 40mA, to predict properties of potential shale gas material from core material from the Bowland shale Roosecote, south Cumbria. Preliminary work showed that, amongst various mineralogical and organic matter properties of the core, regression models could be used so that the total organic carbon content could be predicted from the IR spectra with a 95 percentile confidence prediction error of 0.6% organic carbon, the free hydrocarbons could be predicted with a 95 percentile confidence prediction error of 0.6 mgHC/g rock, the bound hydrocarbons could be predicted with a 95 percentile confidence prediction error of 2.4 mgHC/g rock, mica content

Preparation and modification of VO2 thin film on R-sapphire substrate by rapid thermal process

International Nuclear Information System (INIS)

Zhu Nai-Wei; Hu Ming; Xia Xiao-Xu; Wei Xiao-Ying; Liang Ji-Ran

2014-01-01

The VO 2 thin film with high performance of metal–insulator transition (MIT) is prepared on R-sapphire substrate for the first time by magnetron sputtering with rapid thermal process (RTP). The electrical characteristic and THz transmittance of MIT in VO 2 film are studied by four-point probe method and THz time domain spectrum (THz-TDS). X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and search engine marketing (SEM) are employed to analyze the crystalline structure, valence state, surface morphology of the film. Results indicate that the properties of VO 2 film which is oxidized from the metal vanadium film in oxygen atmosphere are improved with a follow-up RTP modification in nitrogen atmosphere. The crystallization and components of VO 2 film are improved and the film becomes compact and uniform. A better phase transition performance is shown that the resistance changes nearly 3 orders of magnitude with a 2-°C hysteresis width and the THz transmittances are reduced by 64% and 60% in thermal and optical excitation respectively. (interdisciplinary physics and related areas of science and technology)

Science popularization and the Indian constitution - Correspondence

Digital Repository Service at National Institute of Oceanography (India)

Varkey, M.J.

mation System for Science and Techno logy (NISSAT), Central Health Education Bureau, Centre for Enviro n - ment Education, National Institute of Science Communication (NISCOM) and Science magazines like Science Reporter, Down to Earth, Resonance... the learning of science to their immediate social and physical environment. Schools, colleges and NGOs also co n - tribute considerably to popularization of science. CSIR laboratories are e x - pected to orga nize open days for the general public during...

X-ray electromagnetic application technology

International Nuclear Information System (INIS)

2011-01-01

The investigating committee aimed at research on electromagnetic fields in functional devices and X-ray fibers for efficient coherent X-ray generation and their material science, high-precision manufacturing, particularly for X-ray electromagnetic application technology from January 2006 to December 2008. In this report, we describe our research results, in particular, on the topics of synchrotron radiation and free-electron laser, Saga Synchrotron Project, X-ray waveguides and waveguide-based lens-less hard-X-ray imaging, X-ray nanofocusing for capillaries and zone plates, dispersion characteristics in photonics crystal consisting of periodic atoms for nanometer waveguides, electromagnetic characteristics of grid structures for scattering fields of nano-meter electromagnetic waves and X-rays, FDTD parallel computing of fundamental scattering and attenuation characteristics of X-ray for medical imaging diagnosis, orthogonal relations of electromagnetic fields including evanescent field in dispersive medium. (author)

r ben hassine - Bulletin of Materials Science | Indian Academy of ...

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. R BEN HASSINE. Articles written in Bulletin of Materials Science. Volume 40 Issue 1 February 2017 pp 79-85. Effect of Co substitution on the physicochemical properties of La 0.67 Sr 0.22 Ba 0.11 Mn 1 − x Co x O 3 compounds ( 0 ≤ x ≤ 0.3 ) · W CHERIF R BEN HASSINE J A ...

Earth Systems Science: An Analytic Framework

Science.gov (United States)

Finley, Fred N.; Nam, Younkeyong; Oughton, John

2011-01-01

Earth Systems Science (ESS) is emerging rapidly as a discipline and is being used to replace the older earth science education that has been taught as unrelated disciplines--geology, meteorology, astronomy, and oceanography. ESS is complex and is based on the idea that the earth can be understood as a set of interacting natural and social systems.…

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Earth System Science; Information for Authors ... A manuscript must present results of original, unpublished work. ... At this stage, JESS does not accept separate BibTeX files and does not provi de a bst file for ...

Rapid X-Ray Variations of the Geminga Pulsar Wind Nebula

Energy Technology Data Exchange (ETDEWEB)

Hui, C. Y.; Lee, Jongsu [Department of Astronomy and Space Science, Chungnam National University, Daejeon 34134 (Korea, Republic of); Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China); Tam, P. H. T. [School of Physics and Astronomy, Sun Yat-Sen University, Guangzhou 510275 (China); Takata, J. [Institute of Particle Physics and Astronomy, Huazhong University of Science and Technology, Wuhan (China); Cheng, K. S. [Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong); Ryu, Dongsu, E-mail: cyhui@cnu.ac.kr [Department of Physics, UNIST, Ulsan 44919 (Korea, Republic of)

2017-09-10

A recent study by Posselt et al. reported the deepest X-ray investigation of the Geminga pulsar wind nebula (PWN) by using Chandra X-ray Observatory . In comparison with previous studies of this system, a number of new findings have been reported, and we found that these suggest the possible variabilities in various components of this PWN. This motivates us to carry out a dedicated search for the morphological and spectral variations of this complex nebula. We have discovered variabilities on timescales from a few days to a few months from different components of the nebula. The fastest change occurred in the circumstellar environment at a rate of 80% of the speed of light. One of the most spectacular results is the wiggling of a half light-year long tail as an extension of the jet, which is significantly bent by the ram pressure. The jet wiggling occurred at a rate of about 20% of the speed of light. This twisted structure could possibly be a result of a propagating torsional Alfv́en wave. We have also found evidence of spectral hardening along this tail for a period of about nine months.

Media, risk and science

CERN Document Server

Allan, Stuart

2002-01-01

How is science represented by the media? Who defines what counts as a risk, threat or hazard, and why? In what ways do media images of science shape public perceptions? What can cultural and media studies tell us about current scientific controversies? "Media, Risk and Science" is an exciting exploration into an array of important issues, providing a much needed framework for understanding key debates on how the media represent science and risk. In a highly effective way, Stuart Allan weaves together insights from multiple strands of research across diverse disciplines. Among the themes he examines are: the role of science in science fiction, such as "Star Trek"; the problem of 'pseudo-science' in "The X-Files"; and how science is displayed in science museums. Science journalism receives particular attention, with the processes by which science is made 'newsworthy' unravelled for careful scrutiny. The book also includes individual chapters devoted to how the media portray environmental risks, HIV-AIDS, food s...

Direct observation of characteristic dissociation behaviors of hydrate-bearing cores by rapid-scanning X-ray CT imaging

Energy Technology Data Exchange (ETDEWEB)

Ebinuma, T.; Oyama, H.; Utiumi, T.; Nagao, J.; Narita, H. [National Inst. of Advanced Industrial Science and Technology, Toyohiraku, Sapporo (Japan)

2008-07-01

Methane hydrate has significant potential as a new source of energy. Major considerations in developing production methods of methane from hydrates are the fundamental properties of hydrate-bearing sediments, and the dissociation behavior of methane hydrate and the gas and water flow generated by its dissociation in sediments. Marine methane hydrates occur several hundred meters below the sea floor, in a variety of forms. The pore-space filling-type is considered to be the most suited to exploitation, as it is contained within the pore spaces of sandy sediments, and has relatively larger gas permeability compared to other forms. However, shallow sandy sediments are not usually consolidated, and methane hydrate is unstable at normal pressure and temperature. Therefore, common methods are not suitable, and new experimental methods have been developed to study the properties of hydrate-bearing sediment and its dissociation process. This paper presented the results of an experimental study involving the dissociation of artificial methane-hydrate-bearing sediments. The experiment was performed using X-ray computed tomography in order to directly observe dissociation behavior in the sediments and the gas and water flows generated by dissociation. The paper described the depressurization process and presented a schematic diagram of rapid scanning X-ray computed tomography scanner and core holder with tri-axial structure. The experimental apparatus for dissociation of methane hydrate was also illustrated. The thermal stimulation process and hot water injection process were explained. It was concluded that dissociation by depressurization demonstrated that the temperature reduction induced by depressurization depended on the phase equilibrium state of methane hydrate, and that dissociation preferentially occurred at the periphery of the core. This behavior was due to the heat flux from the outside of the core, where the heat flux controlled the dissociation rate. 10 refs

Applications of soft x-ray lasers

International Nuclear Information System (INIS)

Skinner, C.H.

1993-01-01

The high brightness and short pulse duration of soft x-ray lasers provide unique advantages for novel applications. Imaging of biological specimens using x-ray lasers has been demonstrated by several groups. Other applications to fields such as chemistry, material science, plasma diagnostics, and lithography are beginning to emerge. We review the current status of soft x-ray lasers from the perspective of applications, and present an overview of the applications currently being developed

Rapid tracking of metals and other minerals in solid contaminated environments matters (soil, waste) thanks to non-destructive and rapid on-site methods with x-fluorescence. Extended abstract

International Nuclear Information System (INIS)

Bouzonville, A.; Colin, A.; Durin, L.; Gruffat, V.; Chassagnac, T.

2008-05-01

Rapid tracking of metals and other minerals in solid contaminated environments matters greatly to the various firms working in waste disposal. In order to facilitate decision-making that rely on non-destructive and rapid onsite methods of analysis, a review of such methods has been carried out though Scientific publications and Technical reports. Only X-fluorescence is presented as suitable, albeit with some limitations. In order to check the collected bibliographical data and to test both the limits and the limitations imposed by the use of portable XRF instruments, several series of experiments were conducted using two types of portable instruments: a gun-like instrument and a portable-class instrument. With the help of such instruments, the experiments were mainly oriented towards applications that are neglected in field research with regards to waste materials such as: - bulky curbside refuse, - contaminated land, - sludge from the dredging of ports and rivers, - steelwork slurries and dust particles. As these instruments make it possible to obtain samples before analysis, more in-depth evaluation of this aspect is relevant. Thus the number of samples to be analyzed, the kind of conditioning (grinding, sifting), the moisture, are parameters that require evaluation for each individual case and each different type of waste matter. Such aspect can be especially iffy when heterogeneous waste matter like recycling refuse is handled. In fact, the precision of the instruments usually do not cover the regulation thresholds or the techniques that are require by users. It is therefore necessary for the users of these instruments to be aware of the utilization limits and to develop protocols that are suitable for each situation, in order to get readings that are representative and can be interpreted. (authors)

Labour market expectation of Nigerian computer science ...

African Journals Online (AJOL)

... of Nigerian computer science / Information Communication Technology (ICT) graduates. ... It also x-rays the women performance in Computer Science. ... key players were analyzed using variables such as competence, creativity, innovation, ...

Measurement of Double Longitudinal Spin Asymmetry, ALL, for Inclusive 0̂ Production at Forward Rapidity in PHENIX for √s=200 and 500 GeV

Science.gov (United States)

Wolin, Scott

2010-11-01

The Relativistic Heavy Ion Collider (RHIC) is the world's only source of polarized proton-proton collisions which provides access at leading order to δ G(x), the gluon contribution to the proton spin. Previously, PHENIX has only been sensitive to truncated moments of δ G over the limited Bjorken-x range of 0.05 Piston Calorimeter (MPC) at forward rapidity, di-hadron measurements with hadrons at both forward and central rapidities are now possible in PHENIX. Two forward hadrons extend the kinematic coverage for gluons down to x˜10-3. Such an asymmetry measurement for di-hadrons and single hadrons at forward rapidity can be used to improve the constraints on δ G(x) at small x. Here, we discuss the status of these measurements at forward rapidity in PHENIX using the MPC.

Novel Hybrid CMOS X-ray Detector Developments for Future Large Area and High Resolution X-ray Astronomy Missions

Science.gov (United States)

Falcone, Abe

In the coming years, X-ray astronomy will require new soft X-ray detectors that can be read very quickly with low noise and can achieve small pixel sizes over a moderately large focal plane area. These requirements will be present for a variety of X-ray missions that will attempt to address science that was highly ranked by the 2010 Decadal Survey, including missions with science that overlaps with that of IXO and Athena, as well as other missions addressing science topics beyond those of IXO and Athena. An X-ray Surveyor mission was recently chosen by NASA for study by a Science & Technology Definition Team (STDT) so it can be considered as an option for an upcom-ing flagship mission. A mission such as this was endorsed by the NASA long term planning document entitled "Enduring Quests, Daring Visions," and a detailed description of one possible reali-zation of such a mission has been referred to as SMART-X, which was described in a recent NASA RFI response. This provides an example of a future mission concept with these requirements since it has high X-ray throughput and excellent spatial resolution. We propose to continue to modify current active pixel sensor designs, in particular the hybrid CMOS detectors that we have been working with for several years, and implement new in-pixel technologies that will allow us to achieve these ambitious and realistic requirements on a timeline that will make them available to upcoming X-ray missions. This proposal is a continuation of our program that has been work-ing on these developments for the past several years. The first 3 years of the program led to the development of a new circuit design for each pixel, which has now been shown to be suitable for a larger detector array. The proposed activity for the next four years will be to incorporate this pixel design into a new design of a full detector array (2k×2k pixels with digital output) and to fabricate this full-sized device so it can be thoroughly tested and

Theoretical calculation of rapid x-ray transients and radius expansion

International Nuclear Information System (INIS)

Starrfield, S.; Sparks, W.; Truran, J.; Kenyon, S.

1984-01-01

We present the results of a calculation of a thermonuclear runaway on a 10 km neutron star which produced a precursor, radius expansion, and after the envelope had begun to shrink, a seconds x-ray burst about 2500 second later. Although such an event has not yet been observed, decreasing the initial envelope mass should bring the calculations into better agreement with the observations

10x10

DEFF Research Database (Denmark)

10x10 collects personal essays by ten leading contemporary social science scholars on the ten works they each find have formed their own academic development the most. Based on the insights and experiences of people who have formed their various fields in important ways, it offers personal reviews...

Case Studies in Science Education, Booklet X: Vortex as Harbinger.

Science.gov (United States)

Hoke, Gordon

This booklet is the eleventh of a series of 16 booklets that together describe and present findings for a study which involved field observations and a survey of science teaching and learning in American public schools during the school year 1976-77. The study was undertaken to provide the National Science Foundation with a portrayal of current…

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Earth System Science; Volume 114; Issue 6 ... using an X-ray fluorescence spectrometer (LEX),sensitive in the energy range of 1 –10 ... (SIR-2),similar to that used on the Smart-1 mission,in collaboration with ESA.

The founding and development of X-ray crystallography

International Nuclear Information System (INIS)

Mai Zhenhong

2014-01-01

2014 is the centennial of X-ray crystallography. Crystals have played an important role in our lives and in the development of society throughout these 100 years. In July 2012 the 66th General Assembly of the United Nations declared 2014 to be the official International Year of Crystallography (IYCr2014). The discovery of X-ray diffraction by crystals has had a profound impact on science and technology worldwide. It provides for us a distinct image of the arrangement of atoms or/and molecules in crystals. The development of X-ray spectroscopy has made it possible for us to understand the laws of atomic structure, and thus to identify the elements in all kinds of matter. In this article the greatest events in the history of X-ray crystallography, including the development of X-ray sources, detectors, experimental data analysis, and experimental methods are reviewed to commemorate the pioneers who made such important contributions to science and technology. (author)

Rapid prototyping for biomedical engineering: current capabilities and challenges.

Science.gov (United States)

Lantada, Andrés Díaz; Morgado, Pilar Lafont

2012-01-01

A new set of manufacturing technologies has emerged in the past decades to address market requirements in a customized way and to provide support for research tasks that require prototypes. These new techniques and technologies are usually referred to as rapid prototyping and manufacturing technologies, and they allow prototypes to be produced in a wide range of materials with remarkable precision in a couple of hours. Although they have been rapidly incorporated into product development methodologies, they are still under development, and their applications in bioengineering are continuously evolving. Rapid prototyping and manufacturing technologies can be of assistance in every stage of the development process of novel biodevices, to address various problems that can arise in the devices' interactions with biological systems and the fact that the design decisions must be tested carefully. This review focuses on the main fields of application for rapid prototyping in biomedical engineering and health sciences, as well as on the most remarkable challenges and research trends.

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 130; Issue 3. Issue front cover ... More Details Abstract Fulltext PDF. Article ID 22. Synthesis and biological evaluation of some bicyclic [2-(2 .... Non-oxidative methane dehydroaromatization reaction over highly active α-MoC1−x ZSM-5 derived from pretreatment.

Science Communication Training: What Are We Trying to Teach?

Science.gov (United States)

Baram-Tsabari, Ayelet; Lewenstein, Bruce V.

2017-01-01

Rapid growth in public communication of science and technology has led to many diverse training programs. We ask: What are learning goals of science communication training? A comprehensive set of learning goals for future trainings will draw fully from the range of fields that contribute to science communication. Learning goals help decide what to…

Integration of TerraSAR-X, RapidEye and airborne lidar for remote sensing of intertidal bedforms on the upper flats of Norderney (German Wadden Sea)

Science.gov (United States)

Adolph, Winny; Jung, Richard; Schmidt, Alena; Ehlers, Manfred; Heipke, Christian; Bartholomä, Alexander; Farke, Hubert

2017-04-01

The Wadden Sea is a large coastal transition area adjoining the southern North Sea uniting ecological key functions with an important role in coastal protection. The region is strictly protected by EU directives and national law and is a UNESCO World Heritage Site, requiring frequent quality assessments and regular monitoring. In 2014 an intertidal bedform area characterised by alternating crests and water-covered troughs on the tidal flats of the island of Norderney (German Wadden Sea sector) was chosen to test different remote sensing methods for habitat mapping: airborne lidar, satellite-based radar (TerraSAR-X) and electro-optical sensors (RapidEye). The results revealed that, although sensitive to different surface qualities, all sensors were able to image the bedforms. A digital terrain model generated from the lidar data shows crests and slopes of the bedforms with high geometric accuracy in the centimetre range, but high costs limit the operation area. TerraSAR-X data enabled identifying the positions of the bedforms reflecting the residual water in the troughs also with a high resolution of up to 1.1 m, but with larger footprints and much higher temporal availability. RapidEye data are sensitive to differences in sediment moisture employed to identify crest areas, slopes and troughs, with high spatial coverage but the lowest resolution (6.5 m). Monitoring concepts may differ in their remote sensing requirements regarding areal coverage, spatial and temporal resolution, sensitivity and geometric accuracy. Also financial budgets limit the selection of sensors. Thus, combining differing assets into an integrated concept of remote sensing contributes to solving these issues.

X-ray beam splitting design for concurrent imaging at hard X-ray FELs and synchrotron facilities

Czech Academy of Sciences Publication Activity Database

Oberta, Peter; Mokso, R.

2013-01-01

Roč. 729, NOV (2013), s. 85-89 ISSN 0168-9002 R&D Projects: GA MPO FR-TI1/412 Institutional research plan: CEZ:AV0Z10100522 Keywords : diffractive-refractive optics * hard X-ray FEL * X-ray imaging Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.316, year: 2013 http://www.sciencedirect.com/science/article/pii/S0168900213009613

Sensors for x-ray astronomy satellite

International Nuclear Information System (INIS)

Makino, Fumiyoshi; Kondo, Ichiro; Nishioka, Yonero; Kameda, Yoshihiko; Kubo, Masaki.

1980-01-01

For the purpose of observing the cosmic X-ray, the cosmic X-ray astronomy satellite (CORSA-b, named ''Hakucho'', Japanese for cygnus,) was launched Feb. 21, 1979 by Institute of Space and Aeronautical Science, University of Tokyo. The primary objectives of the satellite are: to perform panoramic survey of the space for X-ray bursts and to perform the spectral and temporal measurement of X-ray sources. The very soft X-ray sensor for X-ray observation and the horizon sensor for spacecraft attitude sensing were developed by Toshiba Corporation under technical support by University of Tokyo and Nagoya University for ''Hakucho''. The features of these sensors are outlined in this paper. (author)

Accuracy of Acuros XB and AAA dose calculation for small fields with reference to RapidArc stereotactic treatments

International Nuclear Information System (INIS)

Fogliata, Antonella; Nicolini, Giorgia; Clivio, Alessandro; Vanetti, Eugenio; Cozzi, Luca

2011-01-01

Purpose: To assess the accuracy against measurements of two photon dose calculation algorithms (Acuros XB and the Anisotropic Analytical algorithm AAA) for small fields usable in stereotactic treatments with particular focus on RapidArc. Methods: Acuros XB and AAA were configured for stereotactic use. Baseline accuracy was assessed on small jaw-collimated open fields for different values for the spot sizes parameter in the beam data: 0.0, 0.5, 1, and 2 mm. Data were calculated with a grid of 1 x 1 mm 2 . Investigated fields were: 3 x 3, 2 x 2, 1 x 1, and 0.8 x 0.8 cm 2 with a 6 MV photon beam generated from a Clinac2100iX (Varian, Palo Alto, CA). Profiles, PDD, and output factors were measured in water with a PTW diamond detector (detector size: 4 mm 2 , thickness 0.4 mm) and compared to calculations. Four RapidArc test plans were optimized, calculated and delivered with jaw settings J3 x 3, J2 x 2, and J1 x 1 cm 2 , the last was optimized twice to generate high (H) and low (L) modulation patterns. Each plan consisted of one partial arc (gantry 110 deg. to 250 deg.), and collimator 45 deg. Dose to isocenter was measured in a PTW Octavius phantom and compared to calculations. 2D measurements were performed by means of portal dosimetry with the GLAaS method developed at authors' institute. Analysis was performed with gamma pass-fail test with 3% dose difference and 2 mm distance to agreement thresholds. Results: Open square fields: penumbrae from open field profiles were in good agreement with diamond measurements for 1 mm spot size setting for Acuros XB, and between 0.5 and 1 mm for AAA. Maximum MU difference between calculations and measurements was 1.7% for Acuros XB (0.2% for fields greater than 1 x 1 cm 2 ) with 0.5 or 1 mm spot size. Agreement for AAA was within 0.7% (2.8%) for 0.5 (1 mm) spot size. RapidArc plans: doses were evaluated in a 4 mm diameter structure at isocenter and computed values differed from measurements by 0.0, -0.2, 5.5, and -3.4% for

Pre-Service Science Teacher Preparation in China: Challenges and Promises

Science.gov (United States)

Liu, Enshan; Liu, Cheng; Wang, Jian

2015-01-01

The purpose of this article was to present an overview of pre-service science teacher preparation in China, which is heavily influenced by Chinese tradition, Confucianism, and rapid social and economic development. The policies, science teacher education systems and related programs jointly contribute to producing enough science teachers for…

(EXAFS) X-ray absorption spectroscopy

International Nuclear Information System (INIS)

Craievich, A.F.

1983-01-01

The technique EXAFS (Extended X-Ray Absorption Fine Structure) is presented and its applications using the synchrotron radiation as an incidente beam in Science of Materials and Biophysics are shown. (L.C.) [pt

Portable x-ray fluorescence spectrometer. Innovative technology summary report

International Nuclear Information System (INIS)

1998-12-01

This report describes the application of portable X-ray fluorescence (XRF) spectrometry to characterize materials related to deactivation and decommissioning (D and D) of contaminated facilities. Two portable XRF instruments manufactured by TN Spectrace were used in a technology evaluation as part of the Large-Scale Demonstration Project (LSDP) held at the Chicago Pile-5 Research Reactor (CP-5) located at Argonne National Laboratory (ANL). The LSDP is sponsored by the US Department of Energy (DOE), Office of Science and Technology, Deactivation and Decommissioning Focus Are (DDFA). The objective of the LSDP is to demonstrate innovative technologies or technology applications potentially beneficial to the D and D of contaminated facilities. The portable XRF technology offers several potential benefits for rapid characterization of facility components and contaminants, including significant cost reduction, fast turnaround time,a nd virtually no secondary waste. Field work for the demonstration of the portable XRF technology was performed from August 28--September 3, 1996 and October 30--December 13, 1996

Determination of rare-earth elements in rocks by isotope-excited X-ray fluorescence spectrometry

DEFF Research Database (Denmark)

Kunzendorf, Helmar; Wollenberg, H.A.

1970-01-01

Isotope-excited X-ray fluorescence spectrometry furnishes a rapid determination of rare-earth elements in unprepared rock samples. The samples are excited by 241Am γ-rays, generating X-ray spectra on a multichannel pulse-height analyser. Gaussian peaks of the Kα and Kβ X-ray energies are treated ......-ray spectrometric scan of a longitudinally sliced drill core showed a close correlation between rare-earth abundances and appropriate minerals.......Isotope-excited X-ray fluorescence spectrometry furnishes a rapid determination of rare-earth elements in unprepared rock samples. The samples are excited by 241Am γ-rays, generating X-ray spectra on a multichannel pulse-height analyser. Gaussian peaks of the Kα and Kβ X-ray energies are treated...

Magnetostructural transformation and magnetocaloric effect in Mn48‑x V x Ni42Sn10 ferromagnetic shape memory alloys

Science.gov (United States)

Hassan, Najam ul; Shah, Ishfaq Ahmad; Khan, Tahira; Liu, Jun; Gong, Yuanyuan; Miao, Xuefei; Xu, Feng

2018-03-01

In this work, we tuned the magnetostructural transformation and the coupled magnetocaloric properties of Mn48‑x V x Ni42Sn10 (x = 0, 1, 2, and 3) ferromagnetic shape memory alloys prepared by means of partial replacement of Mn by V. It is observed that the martensitic transformation temperatures decrease with the increase of V content. The shift of the transition temperatures to lower temperatures driven by the applied field, the metamagnetic behavior, and the thermal hysteresis indicates the first-order nature for the magnetostructural transformation. The entropy changes with a magnetic field variation of 0–5 T are 15.2, 18.8, and 24.3 {{J}}\\cdot {kg}}-1\\cdot {{{K}}}-1 for the x = 0, 1, and 2 samples, respectively. The tunable martensitic transformation temperature, enhanced field driving capacity, and large entropy change suggest that Mn48‑x V x Ni42Sn10 alloys have a potential for applications in magnetic cooling refrigeration. Project supported by the National Natural Science Foundation of China (Grant Nos. 51601092, 51571121, and 11604148), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 30916011344 and 30916011345), the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province, China, the Postdoctoral Science Foundation Funded Project (Grant No. 2016M591851), the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20160833, 20160829, and 20140035), the Qing Lan Project of Jiangsu Province, the Priority Academic Program Development of Jiangsu Higher Education Institutions, and Shanxi Scholarship Council of China (Grant No. 2016-092).

Magnetic properties of Sm2Co17-xCrx (0 ≤ x ≤ 3.0) compounds

International Nuclear Information System (INIS)

Fuquan, B.; Wang, J.L.; Tegus, O.; Dagula, W.; Tang, N.; Wang, W.Q.; Yang, F.M.; Brueck, E.; Boer, F.R. de; Buschow, K.H.J.

2004-01-01

The structural and magnetic properties of Sm 2 Co 17-x Cr x (0≤x≤3.0) compounds have been investigated by means of X-ray diffraction and magnetization measurements. The powder X-ray diffraction patterns show that all samples crystallize as a single phase with the rhombohedral Th 2 Zn 17 -type structure. The lattice parameters a and V increase monotonically with increasing Cr content, but the lattice parameter c increases very slowly with increasing Cr content. The X-ray diffraction patterns of the aligned powder of the samples have confirmed that all the compounds investigated have uniaxial anisotropy. The Curie temperature of the compounds decreases rapidly the spontaneous magnetization M 0 , the anisotropy field B a , and the anisotropy constant K 1 of Sm 2 Co 17-x Cr x (0≤x≤3.0) compounds decrease strongly with increasing Cr content

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 35; Issue 5. Effect of rolling deformation and solution treatment on ... By the solution treatment, the elongated and broken crystalline grains recrystallize which leads to the formation of finer grains (<10 m) of austenite. X-ray diffraction analysis has corroborated well with ...

Associations for Citizen Science: Regional Knowledge, Global Collaboration

Directory of Open Access Journals (Sweden)

Martin Storksdieck

2016-11-01

Full Text Available Since 2012, three organizations advancing the work of citizen science practitioners have arisen in different regions: The primarily US-based but globally open Citizen Science Association (CSA, the European Citizen Science Association (ECSA, and the Australian Citizen Science Association (ACSA. These associations are moving rapidly to establish themselves and to develop inter-association collaborations. We consider the factors driving this emergence and the significance of this trend for citizen science as a field of practice, as an area of scholarship, and for the culture of scientific research itself.

magnitude of genotype x environment interaction for bacterial leaf

African Journals Online (AJOL)

ACSS

African Crop Science Journal, Vol. ... effects of treatments into genotype, environment, and genotype x environment (G x E) interactions. Results .... method is economically effective (Niño-Liu et al., ..... This phenomenon indicated differences in.

State-of-the-art and problems of X-ray diffraction analysis of biomacromolecules

International Nuclear Information System (INIS)

Andreeva, N. S.

2006-01-01

The state-of-the-art of X-ray diffraction studies of biomacromolecules is briefly characterized, and the challenge imposed by science is discussed. These studies are characterized by a wide scope and extensive use. This field of science is of great interest and is developed in many countries. The main purpose is to solve practical problems in medicine consisting in the design of drugs against various diseases. X-ray diffraction analysis of enzymes brought the pharmaceutical industry to a new level, thus allowing the rational design of drugs against formerly untreatable diseases. Modern X-ray diffraction studies of biomacromolecules laid the basis for a new science called structural biology. This method allows one to solve fundamental problems of physical chemistry for a new state of matter existing in living systems. Here, science poses numerous problems in analysis of X-ray diffraction data on biological macromolecules. Many of theses problems are in their infancy

Moving Towards a New Urban Systems Science

Science.gov (United States)

Peter M. Groffman; Mary L. Cadenasso; Jeannine Cavender-Bares; Daniel L. Childers; Nancy B. Grimm; Morgan Grove; Sarah E. Hobbie; Lucy R. Hutyra; G. Darrel Jenerette; Timon McPhearson; Diane E. Pataki; Steward T. A. Pickett; Richard V. Pouyat; Emma Rosi-Marshall; Benjamin L. Ruddell

2016-01-01

Research on urban ecosystems rapidly expanded in the 1990s and is now a central topic in ecosystem science. In this paper, we argue that there are two critical challenges for ecosystem science that are rooted in urban ecosystems: (1) predicting or explaining the assembly and function of novel communities and ecosystems under altered environmental conditions and (2)...

Center for X-ray Optics (CXRO)

Data.gov (United States)

Federal Laboratory Consortium — The Center for X-Ray Optics at Lawrence Berkeley National Laboratory works to further science and technology using short wavelength optical systems and techniques....

Portable XRF and principal component analysis for bill characterization in forensic science

International Nuclear Information System (INIS)

Appoloni, C.R.; Melquiades, F.L.

2014-01-01

Several modern techniques have been applied to prevent counterfeiting of money bills. The objective of this study was to demonstrate the potential of Portable X-ray Fluorescence (PXRF) technique and the multivariate analysis method of Principal Component Analysis (PCA) for classification of bills in order to use it in forensic science. Bills of Dollar, Euro and Real (Brazilian currency) were measured directly at different colored regions, without any previous preparation. Spectra interpretation allowed the identification of Ca, Ti, Fe, Cu, Sr, Y, Zr and Pb. PCA analysis separated the bills in three groups and subgroups among Brazilian currency. In conclusion, the samples were classified according to its origin identifying the elements responsible for differentiation and basic pigment composition. PXRF allied to multivariate discriminate methods is a promising technique for rapid and no destructive identification of false bills in forensic science. - Highlights: • The paper is about a direct method for bills discrimination by EDXRF and principal component analysis. • The bills are analyzed directly, without sample preparation and non destructively. • The results demonstrates that the methodology is feasible and could be applied in forensic science for identification of origin and false banknotes. • The novelty is that portable EDXRF is very fast and efficient for bills characterization

Synthesis of single phase chalcopyrite CuIn1−xGaxSe2 (0 ≤ x ≤ 1) nanoparticles by one-pot method

International Nuclear Information System (INIS)

Han, Zhaoxia; Zhang, Dawei; Chen, Qinmiao; Hong, Ruijin; Tao, Chunxian; Huang, Yuanshen; Ni, Zhengji; Zhuang, Songlin

2014-01-01

Graphical abstract: - Highlights: • A facile and rapid one-pot synthesis method is presented. • The effects of various Ga contents are investigated. • Single phase chalcopyrite CuIn 1−x Ga x Se 2 nanoparticles can be easily synthesized. • The phase formation sequence is from CuSe to CuGaSe 2 , then to CuIn 1−x Ga x Se 2 . • The possible reaction mechanism of CuIn 1−x Ga x Se 2 nanoparticles is proposed. - Abstract: Single phase chalcopyrite and near stoichiometric CuIn 1−x Ga x Se 2 (0 ≤ x ≤ 1) nanoparticles were successfully synthesized by using a facile and rapid one-pot method. The effects of various Ga contents on crystal phase, morphology, element composition and absorption spectrum of the as-synthesized CuIn 1−x Ga x Se 2 nanoparticles were investigated in detail. The XRD and Raman patterns indicated that the as-synthesized nanoparticles had a single phase chalcopyrite structure, and the diffraction peaks shifted toward larger diffraction angles or higher frequencies with increasing Ga content. The FE-SEM images showed that the as-synthesized nanoparticles were polydispersed in both size and shape, and the nanoparticles with higher Ga content were more prone to aggregate. The Vis–IR absorption spectra showed strong absorption in the entire visible light region. The estimated band gap increased from 1.00 eV to 1.68 eV as Ga content increasing

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 127; Issue 12. Synthesis, characterization, X-ray crystal structure, ... The Cu(II) center is coordinated by two oxygen and one nitrogen donors of L2− and nitrogen atoms of the heterocyclic group. Electrochemical studies of the Cu(II) complex showed shifts in the ligand ...

High spatial resolution soft-x-ray microscopy

Energy Technology Data Exchange (ETDEWEB)

Meyer-Ilse, W.; Medecki, H.; Brown, J.T. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

A new soft x-ray microscope (XM-1) with high spatial resolution has been constructed by the Center for X-ray Optics. It uses bending magnet radiation from beamline 6.1 at the Advanced Light Source, and is used in a variety of projects and applications in the life and physical sciences. Most of these projects are ongoing. The instrument uses zone plate lenses and achieves a resolution of 43 nm, measured over 10% to 90% intensity with a knife edge test sample. X-ray microscopy permits the imaging of relatively thick samples, up to 10 {mu}m thick, in water. XM-1 has an easy to use interface, that utilizes visible light microscopy to precisely position and focus the specimen. The authors describe applications of this device in the biological sciences, as well as in studying industrial applications including structured polymer samples.

Hard X-ray techniques suitable for polymer experiments

Energy Technology Data Exchange (ETDEWEB)

Bras, W; Goossens, H; Goderis, B, E-mail: Wim.Bras@esrf.fr [Netherlands Organisation for Scientific Research (NWO) (Netherlands); DUBBLE-ESRF, BP 220, F38043 Grenoble Cedex (France); Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands); Molecular and Nanomaterials, Chemistry Department, Catholic University of Leuven, Celestijnenlaan 200F (Belgium)

2010-11-15

Polymers have been studied since 1979 with 8-12 keV synchrotron radiation X-ray scattering methods and the number and sophistication of the experiments have rapidly grown ever since. More recently, new experimental techniques have been developed that use softer or harder X-rays in less conventional ways. This article provides a brief overview of the possibilities of hard X-ray techniques and indicates some areas that might gain from further developments.

Hard X-ray techniques suitable for polymer experiments

International Nuclear Information System (INIS)

Bras, W; Goossens, H; Goderis, B

2010-01-01

Polymers have been studied since 1979 with 8-12 keV synchrotron radiation X-ray scattering methods and the number and sophistication of the experiments have rapidly grown ever since. More recently, new experimental techniques have been developed that use softer or harder X-rays in less conventional ways. This article provides a brief overview of the possibilities of hard X-ray techniques and indicates some areas that might gain from further developments.

Rapid determination of trace phosphorus, sulfur, chlorine, bromine and iodine by energy dispersive X-ray fluorescence analysis with monochromatic excitations

International Nuclear Information System (INIS)

Wakisaka, Tatsushi; Morita, Naoki; Hirabayashi, Tadashi; Nakahara, Taketoshi

1998-01-01

A useful and rapid procedure is described for the determination of trace phosphorus, sulfur, chlorine, bromine, and iodine by means of an energy dispersive X-ray fluorescence spectrometer (EDXRF) with monochromatic excitations. Using monochromatic excitations, the detection limits for phosphorus, sulfur, chlorine (Cr-Kα, 5.41 keV), bromine (Mo-Kα, 17.44 keV), and iodine (W-continuum, 40 keV) were found to be 4.6, 1.7, 0.7, 0.09 and 0.5 μg g -1 , respectively. The relative standard deviations in five replicate measurements were 0.9-1.3%. The proposed method was applied to the direct determination of sulfur in the NIST Residual Fuel Oil, and others. The results obtained by the proposed method were in good agreement with the certified values. Bromine in a seawater sample, as well as iodine and bromine in a brine sample were determined by the proposed method. The obtained results were in good agreement with those obtained by ion chromatography. (author)

Advanced Technology in Small Packages Enables Space Science Research Nanosatellites: Examples from the NASA Miniature X-ray Solar Spectrometer CubeSat

Science.gov (United States)

Woods, T. N.

2017-12-01

Nanosatellites, including the CubeSat class of nanosatellites, are about the size of a shoe box, and the CubeSat modular form factor of a Unit (1U is 10 cm x 10 cm x 10 cm) was originally defined in 1999 as a standardization for students developing nanosatellites. Over the past two decades, the satellite and instrument technologies for nanosatellites have progressed to the sophistication equivalent to the larger satellites, but now available in smaller packages through advanced developments by universities, government labs, and space industries. For example, the Blue Canyon Technologies (BCT) attitude determination and control system (ADCS) has demonstrated 3-axis satellite control from a 0.5-Unit system with 8 arc-second stability using reaction wheels, torque rods, and a star tracker. The first flight demonstration of the BCT ADCS was for the NASA Miniature X-ray Solar Spectrometer (MinXSS) CubeSat. The MinXSS CubeSat mission, which was deployed in May 2016 and had its re-entry in May 2017, provided space weather measurements of the solar soft X-rays (SXR) variability using low-power, miniaturized instruments. The MinXSS solar SXR spectra have been extremely useful for exploring flare energetics and also for validating the broadband SXR measurements from the NOAA GOES X-Ray Sensor (XRS). The technology used in the MinXSS CubeSat and summary of science results from the MinXSS-1 mission will be presented. Web site: http://lasp.colorado.edu/home/minxss/

Accuracy of Acuros XB and AAA dose calculation for small fields with reference to RapidArc stereotactic treatments

Energy Technology Data Exchange (ETDEWEB)

Fogliata, Antonella; Nicolini, Giorgia; Clivio, Alessandro; Vanetti, Eugenio; Cozzi, Luca [Oncology Institute of Southern Switzerland, Medical Physics Unit, CH-6500 Bellinzona (Switzerland)

2011-11-15

Purpose: To assess the accuracy against measurements of two photon dose calculation algorithms (Acuros XB and the Anisotropic Analytical algorithm AAA) for small fields usable in stereotactic treatments with particular focus on RapidArc. Methods: Acuros XB and AAA were configured for stereotactic use. Baseline accuracy was assessed on small jaw-collimated open fields for different values for the spot sizes parameter in the beam data: 0.0, 0.5, 1, and 2 mm. Data were calculated with a grid of 1 x 1 mm{sup 2}. Investigated fields were: 3 x 3, 2 x 2, 1 x 1, and 0.8 x 0.8 cm{sup 2} with a 6 MV photon beam generated from a Clinac2100iX (Varian, Palo Alto, CA). Profiles, PDD, and output factors were measured in water with a PTW diamond detector (detector size: 4 mm{sup 2}, thickness 0.4 mm) and compared to calculations. Four RapidArc test plans were optimized, calculated and delivered with jaw settings J3 x 3, J2 x 2, and J1 x 1 cm{sup 2}, the last was optimized twice to generate high (H) and low (L) modulation patterns. Each plan consisted of one partial arc (gantry 110 deg. to 250 deg.), and collimator 45 deg. Dose to isocenter was measured in a PTW Octavius phantom and compared to calculations. 2D measurements were performed by means of portal dosimetry with the GLAaS method developed at authors' institute. Analysis was performed with gamma pass-fail test with 3% dose difference and 2 mm distance to agreement thresholds. Results: Open square fields: penumbrae from open field profiles were in good agreement with diamond measurements for 1 mm spot size setting for Acuros XB, and between 0.5 and 1 mm for AAA. Maximum MU difference between calculations and measurements was 1.7% for Acuros XB (0.2% for fields greater than 1 x 1 cm{sup 2}) with 0.5 or 1 mm spot size. Agreement for AAA was within 0.7% (2.8%) for 0.5 (1 mm) spot size. RapidArc plans: doses were evaluated in a 4 mm diameter structure at isocenter and computed values differed from measurements by 0.0, -0

JINR rapid communications

International Nuclear Information System (INIS)

1997-01-01

The present collection of rapid communications from JINR, Dubna, contains seven separate reports on investigation of the tensor analyzing power A yy in the reaction A(d polarized, p)X at large transverse momenta of proton, double-differential ionization cross section calculations for fast collisions of ions and atoms, a study of the two-photon interactions tagged at an average 2 > of 90 GeV 2 , cluster and single-particle distributions in nucleus-nucleus interactions, the Coulomb interaction of charged pions in CC-and CTa-collisions at 4.2 A GeV/c, influence of nitrogen and oxygen gas admixtures on the response of the DELPHI HCAL and MUS detectors and an automation of physics research on base of open standards

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 41; Issue 2. Effect of oxygen vacancies on Li-storage of anatase TiO 2 (001) facets: a first principles study. H CHEN Y H DING X Q TANG W ZHANG J R YIN P ZHANG Y JIANG. Volume 41 Issue 2 April 2018 Article ID 51 ...

Climatic shocks associate with innovation in science and technology

NARCIS (Netherlands)

C.K.W. de Dreu (Carsten); Dijk, M.A. (Mathijs) van

2018-01-01

textabstractHuman history is shaped by landmark discoveries in science and technology. However, across both time and space the rate of innovation is erratic: Periods of relative inertia alternate with bursts of creative science and rapid cascades of technological innovations. While the origins of

Efficient and selective heavy metal sequestration from water by using layered sulfide K _2x Sn _4-x S _8-x (x = 0.65–1; KTS-3)

Energy Technology Data Exchange (ETDEWEB)

Sarma, Debajit; Islam, Saiful M.; Subrahmanyam, K. S.; Kanatzidis, Mercouri G.

2016-09-16

Heavy metal ions (Cd²⁺, Hg²⁺, As³⁺ and Pb²⁺) are an important contributor to the contamination of groundwater and other water bodies in and around industrial areas. Herein, we demonstrate the rapid and efficient capacity of a layered metal sulfide material, K2xSn4-xS8-x (x = 0.65-1, KTS-3) for heavy metal ion removal from water. The effect of concentration, pH, kinetics, and competitive ions such as Na⁺/Ca²⁺ on the heavy metal ion removal capacity of KTS-3 was systematically investigated. X-ray photoelectron spectroscopy (XPS), elemental analyses, and powder X-ray diffraction studies revealed that the heavy metal ion-exchange of KTS-3 is complete (quantitative replacement of all potassium ions) and topotactic. The heavy metal ion-exchange by using KTS-3 follows the Langmuir-Freundlich model with high exchange capacities, q(m) 205(17) mg g^-1 for Cd²⁺, 372(21) mg g^-1 for Hg²⁺ and 391(89) mg g^-1 for Pb²⁺. KTS-3 retains excellent heavy metal ion-exchange capacity even in very high concentration (1 M) of competing ions (Na⁺/Ca²⁺) and also over a broad pH range (2-12). KTS-3 also exhibits very good ion-exchange capacity for precious Ag⁺ and toxic As³⁺ ions. The kinetics of heavy metal ion adsorption by KTS-3 are rapid (absorbs all ions within a few minutes). These properties and the environmentally friendly character of KTS-3 make it a promising candidate for sequestration of heavy metal ions from water.

Synchrotron Environmental Science-I Workshop Report

International Nuclear Information System (INIS)

1999-01-01

Attendees of the Synchrotrons Environmental Science 1 (SES-1) workshop represented a broad spectrum of environmental science research areas and expertise in all of the current synchrotrons techniques (X-ray scattering and diffraction, X-ray absorption spectroscopy, and two- and three-dimensional X-ray imaging). These individuals came together to discuss current measurement obstacles in environmental research and, more specifically, ways to overcome such obstacles by applying synchrotrons radiation techniques. Significant obstacles in measurement affect virtually all of the research issues described. Attendees identified synchrotrons approaches of potential value in their research. A number of the environmental research studies discussed are currently being addressed with some success by synchrotron-based approaches. Nevertheless, improvements in low-Z measurement capabilities are needed to facilitate the use of synchrotrons radiation methodologies in environmental research

Synchrotron Environmental Science-I Workshop Report.

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-08

Attendees of the Synchrotrons Environmental Science 1 (SES-1) workshop represented a broad spectrum of environmental science research areas and expertise in all of the current synchrotrons techniques (X-ray scattering and diffraction, X-ray absorption spectroscopy, and two- and three-dimensional X-ray imaging). These individuals came together to discuss current measurement obstacles in environmental research and, more specifically, ways to overcome such obstacles by applying synchrotrons radiation techniques. Significant obstacles in measurement affect virtually all of the research issues described. Attendees identified synchrotrons approaches of potential value in their research. A number of the environmental research studies discussed are currently being addressed with some success by synchrotron-based approaches. Nevertheless, improvements in low-Z measurement capabilities are needed to facilitate the use of synchrotrons radiation methodologies in environmental research.

Aspects of nuclear science

International Nuclear Information System (INIS)

Hageboe, E.; Salbu, B.

1987-01-01

The aspects of nuclear science presented in this book result from a symposium that was held in Oslo in October 1985. On this special occasion the rapid development of nuclear science as an interdisciplinary field was illustrated with brief presentations of some selected areas. These areas represent parts of the main interests of the Section for Nuclear Chemistry in the Department of Chemistry at the University of Oslo. This section has for decades been among the leading laboratories for nuclear chemistry in Scandinavia, thanks to its founder and inspiring leader professor Alexis C. Pappas

Al-Si-Re Alloys Cast by the Rapid Solidification Process / Stopy Al-Si-Re Odlewane Metodą Rapid Solidification

Directory of Open Access Journals (Sweden)

Szymanek M.

2015-12-01

Full Text Available The aim of the studies described in this article was to present the effect of rare earth elements on aluminium alloys produced by an unconventional casting technique. The article gives characteristics of the thin strip of Al-Si-RE alloy produced by Rapid Solidification (RS. The effect of rare earth elements on structure refinement, i.e. on the size of near-eutectic crystallites in an aluminium-silicon alloy, was discussed. To determine the size of crystallites, the Scherrer X-ray diffraction method was used. The results presented capture relationships showing the effect of variable casting parameters and chemical composition on microstructure of the examined alloys. Rapid Solidification applied to Al-Si alloys with the addition of mischmetal (Ce, La, Ne, Pr refines their structure.

AFRL/IF Technology Transition to the Warfighter via the CAOC-X

National Research Council Canada - National Science Library

Phister, Jr., Paul W; Patrick, Scott; Humiston, Todd; Plonisch, Igor G

2002-01-01

...) Combined Air Operations Center Experimental (CAOC-X). The CAOC-X is part of AFC2ISRC's efforts to rapidly develop and field capabilities critical to the warfighter utilizing the spiral development model of system acquisition...

The Miniature X-ray Solar Spectrometer (MinXSS) CubeSats: instrument capabilities and early science analysis on the quiet Sun, active regions, and flares.

Science.gov (United States)

Moore, Christopher S.; Woods, Tom; Caspi, Amir; Dennis, Brian R.; MinXSS Instrument Team, NIST-SURF Measurement Team

2018-01-01

Detection of soft X-rays (sxr) from the Sun provide direct information on coronal plasma at temperatures in excess of ~1 MK, but there have been relatively few solar spectrally resolved measurements from 0.5 – 10. keV. The Miniature X-ray Solar Spectrometer (MinXSS) CubeSat is the first solar science oriented CubeSat mission flown for the NASA Science Mission Directorate, and has provided measurements from 0.8 -12 keV, with resolving power ~40 at 5.9 keV, at a nominal ~10 second time cadence. MinXSS design and development has involved over 40 graduate students supervised by professors and professionals at the University of Colorado at Boulder. Instrument radiometric calibration was performed at the National Institute for Standard and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF) and spectral resolution determined from radioactive X-ray sources. The MinXSS spectra allow for determining coronal abundance variations for Fe, Mg, Ni, Ca, Si, S, and Ar in active regions and during flares. Measurements from the first of the twin CubeSats, MinXSS-1, have proven to be consistent with the Geostationary Operational Environmental Satellite (GOES) 0.1 – 0.8 nm energy flux. Simultaneous MinXSS-1 and Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations have provided the most complete sxr spectral coverage of flares in recent years. These combined measurements are vital in estimating the heating flare loops by non-thermal accelerated electrons. MinXSS-1 measurements have been combined with the Hinode X-ray Telescope (XRT) and Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO-AIA) to further constrain the coronal temperature distribution during quiescent times. The structure of the temperature distribution (especially for T > 5 MK) is important for deducing heating processes in the solar atmosphere. MinXSS-1 observations yield some of the tightest constraints on the high temperature component of the coronal plasma, in the

Surficial Geologic Map of the Roanoke Rapids 30' x 60' Quadrangle, North Carolina

Science.gov (United States)

Weems, Robert E.; Lewis, William C.; Aleman-Gonzalez, Wilma

2009-01-01

The Roanoke Rapids 1:100,000 map sheet is located in northeastern North Carolina. Most of the area is flat to gently rolling, though steep slopes occur occasionally along some of the larger streams. Total relief in the area is slightly less than 400 feet (ft), with elevations ranging from sea level east of Murfreesboro in the far northeastern corner of the map to 384 ft near the northwestern map border near Littleton. The principal streams are the Roanoke River and Fishing Creek, which on average flow from northwest to southeast in the map area. The principal north-south roads are Interstate Route 95, U.S. Route 258, and U.S. Route 301. Two lines of the CSX railroad also cross the area in a north-south and northeast-southwest direction. This part of North Carolina is primarily rural and agricultural. The only large community in the area is Roanoke Rapids. The map lies astride the Tidewater Fall Line, a prominent physiographic feature marked by rapids and waterfalls that separate the rocky streams of the eastern Piedmont physiographic province from the sandy and alluviated streams of the western Atlantic Coastal Plain physiographic province. The energy from the Roanoke River descending the Tidewater Fall Line has been harnessed by dams to produce hydroelectric power, and this source of energy was a major factor in the growth and development of Roanoke Rapids. The Piedmont in the western part of the map area is underlain by Neoproterozoic to Cambrian metavolcanic and metasedimentary rocks that are intruded by granite in some areas. In the central and eastern part of the map area, the folded and faulted igneous and metamorphic rocks of the Piedmont, as well as tilted sedimentary rocks in a buried Triassic basin, are all overlain with profound unconformity by generally unlithified and only slightly eastward-tilted Cretaceous, Paleogene, and Neogene sediments of the Atlantic Coastal Plain. The Coastal Plain sediments lap westward onto the eastern Piedmont along the high

Hard-x-ray phase-difference microscopy with a low-brilliance laboratory x-ray source

International Nuclear Information System (INIS)

Kuwabara, Hiroaki; Yashiro, Wataru; Harasse, Sebastien; Momose, Atsushi; Mizutani, Haruo

2011-01-01

We have developed a hard-X-ray phase-imaging microscopy method using a low-brilliance X-ray source. The microscope consists of a sample, a Fresnel zone plate, a transmission grating, and a source grating creating an array of mutually incoherent X-ray sources. The microscope generates an image exhibiting twin features of the sample with opposite signs separated by a distance, which is processed to generate a phase image. The method is quantitative even for non-weak-phase objects that are difficult to be quantitatively examined by the widely used Zernike phase-contrast microscopy, and it has potentially broad applications in the material and biological science fields. (author)

Molecular science for drug development and biomedicine.

Science.gov (United States)

Zhong, Wei-Zhu; Zhou, Shu-Feng

2014-11-04

With the avalanche of biological sequences generated in the postgenomic age, molecular science is facing an unprecedented challenge, i.e., how to timely utilize the huge amount of data to benefit human beings. Stimulated by such a challenge, a rapid development has taken place in molecular science, particularly in the areas associated with drug development and biomedicine, both experimental and theoretical. The current thematic issue was launched with the focus on the topic of "Molecular Science for Drug Development and Biomedicine", in hopes to further stimulate more useful techniques and findings from various approaches of molecular science for drug development and biomedicine.[...].

The Medical Science DMZ.

Science.gov (United States)

Peisert, Sean; Barnett, William; Dart, Eli; Cuff, James; Grossman, Robert L; Balas, Edward; Berman, Ari; Shankar, Anurag; Tierney, Brian

2016-11-01

We describe use cases and an institutional reference architecture for maintaining high-capacity, data-intensive network flows (e.g., 10, 40, 100 Gbps+) in a scientific, medical context while still adhering to security and privacy laws and regulations. High-end networking, packet filter firewalls, network intrusion detection systems. We describe a "Medical Science DMZ" concept as an option for secure, high-volume transport of large, sensitive data sets between research institutions over national research networks. The exponentially increasing amounts of "omics" data, the rapid increase of high-quality imaging, and other rapidly growing clinical data sets have resulted in the rise of biomedical research "big data." The storage, analysis, and network resources required to process these data and integrate them into patient diagnoses and treatments have grown to scales that strain the capabilities of academic health centers. Some data are not generated locally and cannot be sustained locally, and shared data repositories such as those provided by the National Library of Medicine, the National Cancer Institute, and international partners such as the European Bioinformatics Institute are rapidly growing. The ability to store and compute using these data must therefore be addressed by a combination of local, national, and industry resources that exchange large data sets. Maintaining data-intensive flows that comply with HIPAA and other regulations presents a new challenge for biomedical research. Recognizing this, we describe a strategy that marries performance and security by borrowing from and redefining the concept of a "Science DMZ"-a framework that is used in physical sciences and engineering research to manage high-capacity data flows. By implementing a Medical Science DMZ architecture, biomedical researchers can leverage the scale provided by high-performance computer and cloud storage facilities and national high-speed research networks while preserving privacy and

Scientific conference at the Department of Biomedical Sciences, Russian Academy of Medical Sciences

International Nuclear Information System (INIS)

Rybakova, M.N.

1997-01-01

Review of reports at the scientific conference of the department of biomedical sciences of the Russian Academy of Medical Sciences, held in April, 1997, on the topic of Novel techniques in biomedical studied. Attention was paid to the creation and uses of rapid diagnosis instruments in micro devices, to the development of electron-photon, immuno enzyme and radionuclide techniques and their realization in automatic special equipment. Delay of native industry in creation of scientific-capacious highly efficient products, especially in the field of radiodiagnosis and instruments for laboratory studies was marked

Refinement of the Compton–Rayleigh scatter ratio method for use on the Mars Science Laboratory alpha particle X-ray spectrometer

Energy Technology Data Exchange (ETDEWEB)

Campbell, J.L., E-mail: icampbel@uoguelph.ca [Guelph-Waterloo Physics Institute, University of Guelph, Guelph, Ontario, Canada N1G 2W1 (Canada); Perrett, G.M. [Guelph-Waterloo Physics Institute, University of Guelph, Guelph, Ontario, Canada N1G 2W1 (Canada); Maxwell, J.A. [3A 47 Surrey St. East, Guelph, Ontario, Canada N1H 3P6 (Canada); Nield, E.; Gellert, R. [Guelph-Waterloo Physics Institute, University of Guelph, Guelph, Ontario, Canada N1G 2W1 (Canada); King, P.L. [Research School of Earth Sciences, Australian National University, Canberra, ACT 0200 (Australia); Lee, M.; O’Meara, J.M.; Pradler, I. [Guelph-Waterloo Physics Institute, University of Guelph, Guelph, Ontario, Canada N1G 2W1 (Canada)

2013-05-01

Spectra from the Mars rover alpha particle X-ray spectrometers contain the elastic and inelastic scatter peaks of the plutonium L X-rays emitted by the instrument’s {sup 244}Cm source. Various spectrum fitting approaches are tested using the terrestrial twin of the APXS instrument on the Mars Science Laboratory Curiosity rover, in order to provide accurate extraction of the Lα and Lβ Compton/Rayleigh intensity ratios, which can provide information about light “invisible” constituents such as water in geological samples. A well-defined dependence of C/R ratios upon mean sample atomic number is established using a large and varied set of geochemical reference materials, and the accuracy of this calibration is examined. Detailed attention is paid to the influence of the rubidium and strontium peaks which overlap the Lα scatter peaks. Our Monte Carlo simulation code for prediction of C/R ratios from element concentrations is updated. The ratio between measured and simulated C/R ratios provides a second means of calibration.

MSL Chemistry and Mineralogy X-Ray Diffraction X-Ray Fluorescence (CheMin) Instrument

Science.gov (United States)

Zimmerman, Wayne; Blake, Dave; Harris, William; Morookian, John Michael; Randall, Dave; Reder, Leonard J.; Sarrazin, Phillipe

2013-01-01

This paper provides an overview of the Mars Science Laboratory (MSL) Chemistry and Mineralogy Xray Diffraction (XRD), X-ray Fluorescence (XRF) (CheMin) Instrument, an element of the landed Curiosity rover payload, which landed on Mars in August of 2012. The scientific goal of the MSL mission is to explore and quantitatively assess regions in Gale Crater as a potential habitat for life - past or present. The CheMin instrument will receive Martian rock and soil samples from the MSL Sample Acquisition/Sample Processing and Handling (SA/SPaH) system, and process it utilizing X-Ray spectroscopy methods to determine mineral composition. The Chemin instrument will analyze Martian soil and rocks to enable scientists to investigate geophysical processes occurring on Mars. The CheMin science objectives and proposed surface operations are described along with the CheMin hardware with an emphasis on the system engineering challenges associated with developing such a complex instrument.

Exposure science in an age of rapidly changing climate: challenges and opportunities

Science.gov (United States)

LaKind, Judy S; Overpeck, Jonathan; Breysse, Patrick N; Backer, Lorrie; Richardson, Susan D; Sobus, Jon; Sapkota, Amir; Upperman, Crystal R; Jiang, Chengsheng; Beard, C Ben; Brunkard, J M; Bell, Jesse E; Harris, Ryan; Chretien, Jean-Paul; Peltier, Richard E; Chew, Ginger L; Blount, Benjamin C

2016-01-01

Climate change is anticipated to alter the production, use, release, and fate of environmental chemicals, likely leading to increased uncertainty in exposure and human health risk predictions. Exposure science provides a key connection between changes in climate and associated health outcomes. The theme of the 2015 Annual Meeting of the International Society of Exposure Science—Exposures in an Evolving Environment—brought this issue to the fore. By directing attention to questions that may affect society in profound ways, exposure scientists have an opportunity to conduct “consequential science”—doing science that matters, using our tools for the greater good and to answer key policy questions, and identifying causes leading to implementation of solutions. Understanding the implications of changing exposures on public health may be one of the most consequential areas of study in which exposure scientists could currently be engaged. In this paper, we use a series of case studies to identify exposure data gaps and research paths that will enable us to capture the information necessary for understanding climate change-related human exposures and consequent health impacts. We hope that paper will focus attention on under-developed areas of exposure science that will likely have broad implications for public health. PMID:27485992

American Association for the Advancement of Science

Science.gov (United States)

... Lecture: Richard Harris on Challenges of Replication in Science Elect a Strong Leadership for AAAS: Deadline Ends Soon! Elect a Strong ... 20140730_leadership-seminar_teaser.jpg 13 Nov 2017 Leadership Seminar in Science & Technology Policy... REGISTER event-featured-twothird_Default_200x200. ...

Overview of the Radiation Dosimetry Experiment (RaD-X) Flight Mission

Science.gov (United States)

Mertens, Christopher J.

2016-01-01

The NASA Radiation Dosimetry Experiment (RaD-X) stratospheric balloon flight mission addresses the need to reduce the uncertainty in predicting human exposure to cosmic radiation in the aircraft environment. Measurements were taken that characterize the dosimetric properties of cosmic ray primaries, the ultimate source of aviation radiation exposure, and the cosmic ray secondary radiations that are produced and transported to aviation altitudes. In addition, radiation detectors were flown to assess their potential application to long-term, continuous monitoring of the aircraft radiation environment. RaD-X was successfully launched from Fort Sumner, New Mexico (34.5 N, 104.2 W), on 25 September 2015. Over 18 h of science data were obtained from a total of four different type dosimeters at altitudes above 20 km. The RaD-X flight mission was supported by laboratory radiation exposure testing of the balloon flight dosimeters and also by coordinated radiation measurements taken on ER-2 and commercial aircraft. This paper provides the science background and motivation for the RaD-X flight mission, a brief description of the balloon flight profile and the supporting aircraft flights, and a summary of the articles included in the RaD-X special collection and their contributions to the science goals of the RaD-X mission.

Science communication a practical guide for scientists

CERN Document Server

Bowater, Laura

2012-01-01

Science communication is a rapidly expanding area and meaningful engagement between scientists and the public requires effective communication. Designed to help the novice scientist get started with science communication, this unique guide begins with a short history of science communication before discussing the design and delivery of an effective engagement event. Along with numerous case studies written by highly regarded international contributors, the book discusses how to approach face-to-face science communication and engagement activities with the public while providing tips to avoid potential pitfalls. This book has been written for scientists at all stages of their career, including undergraduates and postgraduates wishing to engage with effective science communication for the first time, or looking to develop their science communication portfolio.

X-ray-induced chromosome aberrations in Down lymphocytes: an explanation of their increased sensitivity

International Nuclear Information System (INIS)

Preston, R.J.

1981-01-01

Unstimulated lymphocytes from individuals with Down Syndrome (trisomy 21) are more sensitive to the induction of dicentric and ring aberrations by X rays than normal lymphocytes. Several explanations involving the more rapid rejoining of X-ray--induced lesions in Down cells have been offered. It is shown here that the repair of the DNA damage converted into chromosome aberrations is more rapid in Down cells than normal cells. This more rapid repair results in a higher probability of producing chromosomes aberrations, and hence higher aberration frequencies in Down than normal cells

X-ray-induced chromosome aberrations in Down lymphocytes: an explanation of their increased sensitivity

International Nuclear Information System (INIS)

Preston, R.J.

1981-01-01

Unstimulated lymphocytes from individuals with Down Syndrome (trisomy 21) are more sensitive to the induction of dicentric and ring aberrations by X rays than normal lymphocytes. Several explanations involving the more rapid rejoining of X-ray-induced lesions in Down cells have been offered. It is shown here that the repair of the DNA damage converted into chromosome aberrations is more rapid in Down cells than normal cells. This more rapid repair results in a higher probability of producing chromosome aberrations, and hence higher aberration frequencies in Down than normal cells

[Application of rapid PCR to authenticate medicinal snakes].

Science.gov (United States)

Chen, Kang; Jiang, Chao; Yuan, Yuan; Huang, Lu-Qi; Li, Man

2014-10-01

To obtained an accurate, rapid and efficient method for authenticate medicinal snakes listed in Chinese Pharmacopoeia (Zaocysd humnades, Bungarus multicinctus, Agkistrodon acutus), a rapid PCR method for authenticate snakes and its adulterants was established based on the classic molecular authentication methods. DNA was extracted by alkaline lysis and the specific primers were amplified by two-steps PCR amplification method. The denatured and annealing temperature and cycle numbers were optimized. When 100 x SYBR Green I was added in the PCR product, strong green fluorescence was visualized under 365 nm UV whereas adulterants without. The whole process can complete in 30-45 minutes. The established method provides the technical support for authentication of the snakes on field.

Anomalous magnetic ordering in Dy_xPr_1-x alloys

DEFF Research Database (Denmark)

Clegg, P.S.; Cowley, R.A.; Goff, J.P.

2000-01-01

Epitaxial thin-films of DyxPr1-x alloys have been studied using neutron diffraction and magnetization measurements. The crystal structure changes from HCP to Sm type to DHCP as x decreases; each crystal phase has different magnetic behaviour. Surprisingly, long-range order is suppressed in the DH...... allays, a possible explanation is outlined. (C) 2000 Elsevier Science B.V. All rights reserved....

Microbeam X-ray analysis in Poland - past and future

International Nuclear Information System (INIS)

Kusinski, J

2010-01-01

The article provides an overview of the development of electron beam X-ray microanalysis (EPMA) in Poland. Since the introduction by Prof. Bojarski of EMPA over 45 years ago, tremendous advances in methodologies and in instrumentation have been made in order to improve the precision of quantitative compositional analysis, spatial resolution and analytical sensitivity. This was possible due to the activity of Applied Crystallography Committee at the Polish Academy of Sciences, as well as the groups of researches working in the Institute for Ferrous Metallurgy (Gliwice), the Technical University of Warsaw, the Silesian Technical University (Katowice), the AGH-University of Sciences and Technology (Krakow), and the Institute of Materials Science and Metallurgy Polish Academy of Sciences (Krakow). Based on the research examples realized by these teams, conferences, seminars and congresses organized, as well as books and academic textbooks issued, the evolution of electron beam X-ray microanalysis in Poland is demonstrated.

Rapid Synthesis of Highly Monodisperse Au x Ag 1− x Alloy Nanoparticles via a Half-Seeding Approach

KAUST Repository

Chng, Ting Ting; Polavarapu, Lakshminarayana; Xu, Qing Hua; Ji, Wei; Zeng, Hua Chun

2011-01-01

Gold-silver alloy AuxAg1-x is an important class of functional materials promising new applications across a wide array of technological fields. In this paper, we report a fast and facile synthetic protocol for preparation of highly monodisperse Aux

Recent activity of the Rapid Burster (MXB 1730-335)

DEFF Research Database (Denmark)

Kuulkers, E.; Brandt, Søren Kristian; Markwardt, C.

2008-01-01

Observations taken as part of the INTEGRAL Galactic bulge monitoring program (see ATel #1385) on 2008, February 23 13:32-17:13 (UT) showed bursting activity from the X-ray transient, the Rapid Burster (MXB 1730-335). During one of the 1800-sec pointings when the source was in the field- of-view o...

Automated rapid particle investigation using scanning electron microscopy

Science.gov (United States)

Wilkins, Jerod Laurence

The chemical composition of fly ash particles has been known to vary significantly depending on a number of factors. Current bulk methods of investigation including X-Ray Fluorescence and X-Ray Diffraction are thought to be inadequate in determining the performance of fly ash in concrete. It is the goal of this research to develop a method of Automated Rapid Particle Investigation that will not look at fly ash as a bulk material but as individual particles. By examining each particle individually scientists and engineers will have the ability to study the variation in chemical composition by comparing the chemistry present in each particle. The method of investigation developed by this research provides a practical technique that will allow the automated chemical analysis of hundreds, or even thousands, of fly ash particles in a matter of minutes upon completion of sample preparation and automated scanning electron microscope (ASEM) scanning. This research does not examine the significance of the chemical compounds discovered; rather, only the investigation methodology is discussed. Further research will be done to examine the importance of the chemistry discovered with this automated rapid particle investigation technique.

Butterflies & Wild Bees: Biology Teachers' PCK Development through Citizen Science

Science.gov (United States)

Scheuch, Martin; Panhuber, Tanja; Winter, Silvia; Kelemen-Finan, Julia; Bardy-Durchhalter, Manfred; Kapelari, Suzanne

2018-01-01

Citizen science is a rapidly growing emerging field in science and it is gaining importance in education. Therefore, this study was conducted to document the pedagogical content knowledge (PCK) of biology teachers who participated in a citizen science project involving observation of wild bees and identification of butterflies. In this paper,…

A Reexamination of Ontario's Science Curriculum: Toward a More Inclusive Multicultural Science Education?

Science.gov (United States)

Mujawamariya, Donatille; Hujaleh, Filsan; Lima-Kerckhoff, Ashley

2014-01-01

The rapid diversification of communities in Ontario has necessitated the provincial government to reevaluate public school curriculums and policies to make schools more inclusive and reflective of its diverse population. This article critically analyzes the content of the latest revised science curricula for Grades 1 to 10 and assesses the degree…

X-ray imaging: Status and trends

International Nuclear Information System (INIS)

Ryon, R.W.; Martz, H.E.; Hernandez, J.M.; Haskins, J.J.; Day, R.A.; Brase, J.M.; Cross, B.; Wherry, D.

1987-08-01

There is a veritable renaissance occurring in x-ray imaging. X-ray imaging by radiography has been a highly developed technology in medicine and industry for many years. However, high resolution imaging has not generally been practical because sources have been relatively dim and diffuse, optical elements have been nonexistent for most applications, and detectors have been slow and of low resolution. Materials analysis needs have therefore gone unmet. Rapid progress is now taking place because we are able to exploit developments in microelectronics and related material fabrication techniques, and because of the availability of intense x-ray sources. This report describes the methods and uses of x-ray imaging along with a discussion of technology advances in these areas

JPRS Report, Science & Technology, China

Science.gov (United States)

1992-06-18

Chile 1987 0.5 Thailand 1985 0.3 JPRS-CST-92-012 18 June 1992 SCIENCE & TECHNOLOGY POLICY 25 (3) Criteria For Testing Government Disbursements...8217.*, •> ■yiH’v;,!- ! \\%v.7X’>A->:-:-.-:v^>.*>>;v< vih >x-«v.; ’mmii The new Chinese Super VGA Card, as shown above, was developed by the Beijing Legend

A real-time loop-mediated isothermal amplification assay for rapid detection of Shigella species.

Science.gov (United States)

Liew, P S; Teh, C S J; Lau, Y L; Thong, K L

2014-12-01

Shigellosis is a foodborne illness caused by the genus Shigella and is an important global health issue. The development of effective techniques for rapid detection of this pathogen is essential for breaking the chain of transmission. Therefore, we have developed a novel loop-mediated isothermal amplification (LAMP) assay targeting the invasion plasmid antigen H (ipaH) gene to rapidly detect Shigella species. This assay could be performed in 90 min at an optimal temperature of 64ºC, with endpoint results visualized directly. Notably, the method was found to be more sensitive than conventional PCR. Indeed, the detection limit for the LAMP assay on pure bacterial cultures was 5.9 x 10(5) CFU/ml, while PCR displayed a limit of 5.9 x 10(7) CFU/ml. In spiked lettuce samples, the sensitivity of the LAMP assay was 3.6 x 10(4) CFU/g, whereas PCR was 3.6 x 10(5) CFU/g. Overall, the assay accurately identified 32 Shigella spp. with one enteroinvasive Escherichia coli displaying positive reaction while the remaining 32 non-Shigella strains tested were negative.

Ultracompact X-ray binary stars

NARCIS (Netherlands)

Haaften, L.M. van

2013-01-01

Ultracompact X-ray binary stars usually consist of a neutron star and a white dwarf, two stars bound together by their strong gravity and orbiting each other very rapidly, completing one orbit in less than one hour. Neutron stars are extremely compact remnants of the collapsed cores of massive stars

Resonance journal of science education

Indian Academy of Sciences (India)

Resonance journal of science education. July 2007 Volume 12 Number 7. GENERAL ARTICLES. 04 Josiah Willard Gibbs. V Kumaran. 12 Josiah Willard ... IISc, Bangalore). Rapidity: The Physical Meaning of the Hyperbolic Angle in. Special Relativity. Giorgio Goldoni. Survival in Stationary Phase. S Mahadevan. Classroom.

X-ray imaging and spectroscopic measurements of implosions

International Nuclear Information System (INIS)

Hammel, B.A.; Ress, D.R.; Keane, C.J.; Kilkenny, J.D.; Landen, O.L.; Bell, P.; Pasha, R.; Wallace, R.J.; Bradley, D.K.

1992-01-01

Time-resolved x-ray measurements are essential in the investigation of laser-driven inertial confinement fusion, where neutron and x-ray emission are the only observable signatures of the compressed core conditions. High-speed detectors, available for x-ray measurement, provide a means of measuring the rapidly evolving conditions in imploding capsules on picosecond time scales. We address a wide range of issues in our indirectly driven implosion experiments on Nova, with a large variety of x-ray measurement techniques. Critical issues include symmetry of the compressed core, fuel density and temperature and hydrodynamic mix at the pusher/fuel interface

Rapidly solidified prealloyed powders by laser spin atomization

Science.gov (United States)

Konitzer, D. G.; Walters, K. W.; Heiser, E. L.; Fraser, H. L.

1984-01-01

A new technique, termed laser spin atomization, for the production of rapidly solidified prealloyed powders is described. The results of experiments involving the production of powders of two alloys, one based on Ni, the other on Ti, are presented. The powders have been characterized using light optical metallography, scanning electron microscopy, energy dispersive X-ray spectroscopy, and Auger elec-tron spectroscopy, and these various observations are described.

X-ray fluorescence imaging with synchrotron radiation

International Nuclear Information System (INIS)

Rivers, M.L.

1987-01-01

The micro-distribution of trace elements is of great interest in fields such as geochemistry, biology and material science. The synchrotron x-ray fluorescence microprobe provides a technique to quantitatively measure trace element compositions at individual points and to construct semiquantitative two dimensional maps of trace element compositions. This paper describes an x-ray fluorescence system used at the National Synchrotron Light Source

Using rapid scan EPR to improve the detection limit of quantitative EPR by more than one order of magnitude

OpenAIRE

Möser, J.; Lips, K.; Tseytlin, M.; Eaton, G.; Eaton, S.; Schnegg, A

2017-01-01

X band rapid scan EPR was implemented on a commercially available Bruker ELEXSYS E580 spectrometer. Room temperature rapid scan and continuous wave EPR spectra were recorded for amorphous silicon powder samples. By comparing the resulting signal intensities the feasibility of performing quantitative rapid scan EPR is demonstrated. For different hydrogenated amorphous silicon samples, rapid scan EPR results in signal to noise improvements by factors between 10 and 50. Rapid scan EPR is thus ca...

JINR Rapid Communications. Collection

International Nuclear Information System (INIS)

1994-01-01

The present collection of rapid communications from JINR, Dubna, contains eight separate reports on Lorentz transformations with superluminal velocities, photo chromic effect in HTSC films, the investigation of hypernuclei in the Nuclotron accelerator, a new hadron jets finding algorithm in the four-dimensional velocity space, investigations of neutral particle production by relativistic nuclei on the LHE 90-channel γ-spectrometer (results and perspectives), coherent meson production in the dp → 3 HeX reaction, the relativistic projectile nuclei fragmentation and A-dependence of nucleon Fermi-momenta, energy spectra of γ-quanta from d-propane interactions at momentum P d = 1.25 GeV/c per nucleon. 86 refs., 26 figs., 4 tabs

JINR Rapid Communications. Collection

International Nuclear Information System (INIS)

1994-01-01

The present collection of rapid communications from JINR, Dubna, contains nine separate reports on quasi-classical description of one-nucleon transfer reactions with heavy ions, elastic and inelastic scattering in the high energy approximation, experimental study of fission and evaporation cross sections for 6 He + 209 Bi reaction, d ↑ + 12 C → p + X at Θ p = 0 o in the region of high internal momenta in the deuteron, the Nuclotron internal targets, actively screened superconducting magnets, using of polarized target in backward elastic dp scattering, application of transputers in the data acquisition system of the INESS-ALPHA spectrometer, narrow dibaryon resonances with isotopic spin I=2. 93 refs., 27 figs., 4 tabs

Evaluation of quality control in the college of medical radiological sciences, conventional x-ray department

International Nuclear Information System (INIS)

Babiker, Esameldeen Mohamed Tom

2002-02-01

Quality control in diagnostic radiography aims to ensure continuous production of diagnostic images with optimum quality, using minimum necessary dose to the patients and staff. Therefore an ineffective quality control program can lead to poor quality images that can impair diagnosis, increase operating costs and contribute to unnecessary radiation exposure to both patients and staff. Apply basic quality control program is responsibility of each x-ray facility, and to achieve maximum benefits, all levels of management and technical staff must support and participate in operating the programme. The main parameters to be monitored during the quality control programme include: dose consistency, k Vp accuracy, k Vp variations, exposure timer accuracy, besides checking image receptors, recording system and processing conditions. The aims of this project is to evaluate the quality control in the x-ray department of the college of medical radiologic sciences. The evaluation was an experimental study done by checking the operational status of the radiographic equipment, beside data collection using questionnaires regarding quality control. In the applied experiments the results show that there is a noted variation in the accuracy of k Vp, exposure timer and also in the dose consistency. The obtained results from image receptors and processing system showed noted variations too. The results of the questionnaire and direct interviewing showed other causes of quality degradation such as absence of test tools, the status of the equipment, absence of regular quality control testing, in addition to absence of an organized team to deal with quality. (Author)

Rapidly worsening bulbar symptoms in a patient with spinobulbar muscular atrophy

Directory of Open Access Journals (Sweden)

Montserrat Diaz-Abad

2013-12-01

Full Text Available X-linked spinobulbar muscular atrophy (Kennedy’s disease affects muscles and motor neurons, manifesting as weakness and wasting of bulbar, facial, and proximal limb muscles due to loss of anterior horn cells in the brain and spinal cord. We present the case of a patient with X-linked spinobulbar muscular atrophy with rapidly worsening bulbar symptoms caused by laryngopharyngeal irritation associated with a viral upper respiratory tract infection, seasonal allergies and laryngopharyngeal reflux, who dramatically improved with multimodality therapy.

Historical development of synchrotron x-ray diffraction topography

International Nuclear Information System (INIS)

Kawado, Seiji

2011-01-01

After a short history of X-ray diffraction topography, from the early stage of laboratory X-ray topography to recent synchrotron-radiation applications, is described, the development of science and technology for the synchrotron X-ray topography and its industrial applications are reviewed in more detail. In addition, the recent trend to synchrotron topography research is clarified on the basis of several data obtained from 256 papers which have been published since 2000. (author)

The medical science DMZ: a network design pattern for data-intensive medical science

Energy Technology Data Exchange (ETDEWEB)

Peisert, Sean [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Davis, CA (United States). Dept. of computer Science; Corporation for Education Network Initiatives in California (CENIC), Berkeley, CA (United States); Dart, Eli [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). ESnet; Barnett, William [Indiana Univ., Indianapolis, IN (United States). Indiana Clinical and Translational Sciences Inst., Regenstrief Inst.; Balas, Edward [Indiana Univ., Bloomington, IN (United States). Global Research Network Operations Center; Cuff, James [Harvard Univ., Cambridge, MA (United States). Research Computing; Grossman, Robert L. [Univ. of Chicago, IL (United States). Center for Data Intensive Science; Berman, Ari [BioTeam, Middleton, MA (United States); Shankar, Anurag [Indiana Univ., Bloomington, IN (United States). Pervasive Technology Inst.; Tierney, Brian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). ESnet

2017-10-06

We describe a detailed solution for maintaining high-capacity, data-intensive network flows (eg, 10, 40, 100 Gbps+) in a scientific, medical context while still adhering to security and privacy laws and regulations.High-end networking, packet-filter firewalls, network intrusion-detection systems.We describe a "Medical Science DMZ" concept as an option for secure, high-volume transport of large, sensitive datasets between research institutions over national research networks, and give 3 detailed descriptions of implemented Medical Science DMZs.The exponentially increasing amounts of "omics" data, high-quality imaging, and other rapidly growing clinical datasets have resulted in the rise of biomedical research "Big Data." The storage, analysis, and network resources required to process these data and integrate them into patient diagnoses and treatments have grown to scales that strain the capabilities of academic health centers. Some data are not generated locally and cannot be sustained locally, and shared data repositories such as those provided by the National Library of Medicine, the National Cancer Institute, and international partners such as the European Bioinformatics Institute are rapidly growing. The ability to store and compute using these data must therefore be addressed by a combination of local, national, and industry resources that exchange large datasets. Maintaining data-intensive flows that comply with the Health Insurance Portability and Accountability Act (HIPAA) and other regulations presents a new challenge for biomedical research. We describe a strategy that marries performance and security by borrowing from and redefining the concept of a Science DMZ, a framework that is used in physical sciences and engineering research to manage high-capacity data flows.By implementing a Medical Science DMZ architecture, biomedical researchers can leverage the scale provided by high-performance computer and cloud storage facilities and national high

X-ray scan detection for cargo integrity

Science.gov (United States)

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.

Multi-anode linear SDDs for high-resolution X-ray spectroscopy

NARCIS (Netherlands)

Sonsky, J.

2002-01-01

Radiation detectors are used in a variety of fields to sense X-rays and y-rays, visible, UV and IR photons, neutrons or charged particles. With their help, advanced medical diagnostics can be performed (e.g. X-ray radiography, computed tomography, fluoroscopy), material research can undergo a rapid

Methods for Rapid Screening in Woody Plant Herbicide Development

Directory of Open Access Journals (Sweden)

William Stanley

2014-07-01

Full Text Available Methods for woody plant herbicide screening were assayed with the goal of reducing resources and time required to conduct preliminary screenings for new products. Rapid screening methods tested included greenhouse seedling screening, germinal screening, and seed screening. Triclopyr and eight experimental herbicides from Dow AgroSciences (DAS 313, 402, 534, 548, 602, 729, 779, and 896 were tested on black locust, loblolly pine, red maple, sweetgum, and water oak. Screening results detected differences in herbicide and species in all experiments in much less time (days to weeks than traditional field screenings and consumed significantly less resources (<500 mg acid equivalent per herbicide per screening. Using regression analysis, various rapid screening methods were linked into a system capable of rapidly and inexpensively assessing herbicide efficacy and spectrum of activity. Implementation of such a system could streamline early-stage herbicide development leading to field trials, potentially freeing resources for use in development of beneficial new herbicide products.

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

The Chandrayaan-1 mission to the Moon scheduled for launch in late 2007 will include a high energy X-ray spectrometer (HEX) for detection of naturally occurring emissions from the lunar surface due to radioactive decay of the 238U and 232Th series nuclides in the energy region 20 –250 keV.The primary science ...

Journal of Astrophysics and Astronomy | Indian Academy of Sciences

Indian Academy of Sciences (India)

R. S. Yang1 J. H. Yang1 2 Y. X. Wang3 J. H. Fan2. Department of Physics and Electronics Science, Hunan University of Arts and Science, Changde 415000, China. Center for Astrophysics, Guangzhou University, Guangzhou 510006, China. College of Science and Trade, Guangzhou University, Guangzhou 511442, China.

Rapid detection of EBOLA VP40 in microchip immunofiltration assay

Science.gov (United States)

Miethe, Peter; Gary, Dominik; Hlawatsch, Nadine; Gad, Anne-Marie

2015-05-01

In the spring of 2014, the Ebola virus (EBOV) strain Zaire caused a dramatic outbreak in several regions of West Africa. The RT-PCR and antigen capture diagnostic proved to be effective for detecting EBOV in blood and serum. In this paper, we present data of a rapid antigen capture test for the detection of VP40. The test was performed in a microfluidic chip for immunofiltration analysis. The chip integrates all necessary assay components. The analytical sensitivity of the rapid test was 8 ng/ml for recombinant VP40. In serum and whole blood samples spiked with virus culture material, the detection limit was 2.2 x 102 PFU/ml. The performance data of the rapid test (15 min) are comparable to that of the VP40 laboratory ELISA.

Development of X-ray excitable luminescent probes for scanning X-ray microscopy

International Nuclear Information System (INIS)

Moronne, M.M.

1999-01-01

Transmission soft X-ray microscopy is now capable of achieving resolutions that are typically 5 times better than the best-visible light microscopes. With expected improvements in zone plate optics, an additional factor of two may be realized within the next few years. Despite the high resolution now available with X-ray microscopes and the high X-ray contrast provided by biological molecules in the soft X-ray region (λ=2-5 nm), molecular probes for localizing specific biological targets have been lacking. To circumvent this problem, X-ray excitable molecular probes are needed that can target unique biological features. In this paper we report our initial results on the development of lanthanide-based fluorescent probes for biological labeling. Using scanning luminescence X-ray microscopy (SLXM, Jacobsen et al., J. Microscopy 172 (1993) 121-129), we show that lanthanide organo-polychelate complexes are sufficiently bright and radiation resistant to be the basis of a new class of X-ray excitable molecular probes capable of providing at least a fivefold improvement in resolution over visible light microscopy. Lanthanide probes, able to bind 80-100 metal ions per molecule, were found to give strong luminescent signals with X-ray doses exceeding 10 8 Gy, and were used to label actin stress fibers and in vitro preparations of polymerized tubulin. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

X-Ray Outburst from Young Star in McNeil's Nebula

Science.gov (United States)

2004-07-01

sudden infall of matter onto the surface of the star from an orbiting disk of gas. In general, the coupling of the magnetic field of the star and the magnetic field of its circumstellar disk regulates the inflow of gas from the disk onto the star. This slow, steady inflow suddenly can become much more rapid if a large amount of gas accumulates in the disk, and the disk and the star are rotating at different rates. The differing rotation rates would twist and shear the magnetic field, storing up energy. This energy is eventually released in an energetic, X-ray producing outburst as the magnetic field violently rearranges back to a more stable state. During this period, a large amount of gas can fall onto the star, producing the observed optical and infrared outburst. A new buildup of gas in the disk could lead to a new outburst in the future. Such a scenario may explain why the brightness of McNeil's Nebula appears to vary with time. It is faintly present in surveys of this region of Orion in images taken in the 1960s, but absent from images taken in the 1950s and 1990s. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for NASA's Office of Space Science, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass. Additional information and images are available at: http://chandra.harvard.edu and http://chandra.nasa.gov

Ultrasonic acoustic levitation for fast frame rate X-ray protein crystallography at room temperature

OpenAIRE

Soichiro Tsujino; Takashi Tomizaki

2016-01-01

Increasing the data acquisition rate of X-ray diffraction images for macromolecular crystals at room temperature at synchrotrons has the potential to significantly accelerate both structural analysis of biomolecules and structure-based drug developments. Using lysozyme model crystals, we demonstrated the rapid acquisition of X-ray diffraction datasets by combining a high frame rate pixel array detector with ultrasonic acoustic levitation of protein crystals in liquid droplets. The rapid spinn...

Study on the management of the Boohung X-Dol 90 developer and fixing solution for automatic X-ray film processor

International Nuclear Information System (INIS)

Hyan, Yong Sil; Kim, Heung Tae; Kwon, Dal Gwan; Choi, Myung Joon; Cheung, Hwan

1986-01-01

Recently, Demands of Automatic X-ray film Processors are increasing more and more at University Hospitals and general Hospitals and Private clinics, but various troubles because of incorrect control were found out. Authors have researched to find out the function and Activity of Automatic X-ray film processor for 2 weeks Kodak RPX-OMAT Processor and Sakura GX3000 Processor and Doosan parka 2000 Processor and results obtained were as follows: 1. Automatic X-ray film processor have an advantage to conduct the rapid treatment of X-ray film processing but incorrect handling of developing and fixing agents were brought about a great change in Contrast and Optical density of X-ray film pictures. 2. About 300 X-ray film could be finished by same developing and fixing solution without exchanging any other solutions in each Automatic X-ray film processor

Hard X-ray Microscopy with Elemental, Chemical and Structural Contrast

International Nuclear Information System (INIS)

Schroer, C.G.; Boye, P.; Feldkamp, J.P.

2010-01-01

We review hard X-ray microscopy techniques with a focus on scanning microscopy with synchrotron radiation. Its strength compared to other microscopies is the large penetration depth of hard x rays in matter that allows one to investigate the interior of an object without destructive sample preparation. In combination with tomography, local information from inside of a specimen can be obtained, even from inside special non-ambient sample environments. Different X-ray analytical techniques can be used to produce contrast, such as X-ray absorption, fluorescence, and diffraction, to yield chemical, elemental, and structural information about the sample, respectively. This makes X-ray microscopy attractive to many fields of science, ranging from physics and chemistry to materials, geo-, and environmental science, biomedicine, and nanotechnology. Our scanning microscope based on nanofocusing refractive X-ray lenses has a routine spatial resolution of about 100 nm and supports the contrast mechanisms mentioned above. In combination with coherent X-ray diffraction imaging, the spatial resolution can be improved to the 10 nm range. The current state-of-the-art of this technique is illustrated by several examples, and future prospects of the technique are given. (author)

Is a Universal Science of Complexity Conceivable?

Science.gov (United States)

West, Geoffrey B.

Over the past quarter of a century, terms like complex adaptive system, the science of complexity, emergent behavior, self-organization, and adaptive dynamics have entered the literature, reflecting the rapid growth in collaborative, trans-disciplinary research on fundamental problems in complex systems ranging across the entire spectrum of science from the origin and dynamics of organisms and ecosystems to financial markets, corporate dynamics, urbanization and the human brain...

Riccardo Giacconi to Receive National Medal of Science

Science.gov (United States)

2005-02-01

Riccardo Giacconi, very recently retired President of Associated Universities, Inc. (AUI), will be awarded the National Medal of Science by President George W. Bush on March 14, according to the White House. Giacconi, who received the Nobel Prize in Physics in 2002, will be honored for his pioneering research in X-ray astronomy and for his visionary leadership of major astronomy facilities. Established by Congress in 1959, the National Medal of Science is the Nation's highest honor for American scientists and is awarded annually by the President of the United States to individuals "deserving of special recognition for their outstanding contributions to knowledge." "We are extremely proud that Riccardo Giacconi has been selected to receive the nation's highest award for scientific achievement," said current AUI President Ethan J. Schreier, a long-term colleague of Dr. Giacconi. "It is another fitting recognition for an outstanding scientific career that has enhanced our basic understanding of the universe," Schreier added. Giacconi, known as the father of X-ray astronomy, used X-ray detectors launched on rockets to discover the first cosmic X-ray source in 1962. Because X-ray radiation is absorbed in Earth's atmosphere, space-based instruments are necessary to study it. Giacconi outlined a methodical program to investigate this new X-ray universe and, working with his research group at American Science and Engineering, Inc. in Cambridge, Massachusetts, developed the first space satellite dedicated to the new field of X-ray astronomy. Named Uhuru, this X-ray satellite observatory was launched in 1970 and subsequently discovered hundreds of X-ray sources. The ground-breaking work of Giacconi and his group led to the discovery of black holes, which to that point had been hypothesized but never seen. Giacconi was also the first to prove that the universe contains background radiation of X-ray light. Riccardo Giacconi has played a key role in many other landmark

Neutron and X-ray Detectors

Energy Technology Data Exchange (ETDEWEB)

Carini, Gabriella [SLAC National Accelerator Lab., Menlo Park, CA (United States); Denes, Peter [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gruener, Sol [Cornell Univ., Ithaca, NY (United States); Lessner, Elianne [Dept. of Energy (DOE), Washington DC (United States). Office of Science Office of Basic Energy Sciences

2012-08-01

The Basic Energy Sciences (BES) X-ray and neutron user facilities attract more than 12,000 researchers each year to perform cutting-edge science at these state-of-the-art sources. While impressive breakthroughs in X-ray and neutron sources give us the powerful illumination needed to peer into the nano- to mesoscale world, a stumbling block continues to be the distinct lag in detector development, which is slowing progress toward data collection and analysis. Urgently needed detector improvements would reveal chemical composition and bonding in 3-D and in real time, allow researchers to watch “movies” of essential life processes as they happen, and make much more efficient use of every X-ray and neutron produced by the source The immense scientific potential that will come from better detectors has triggered worldwide activity in this area. Europe in particular has made impressive strides, outpacing the United States on several fronts. Maintaining a vital U.S. leadership in this key research endeavor will require targeted investments in detector R&D and infrastructure. To clarify the gap between detector development and source advances, and to identify opportunities to maximize the scientific impact of BES user facilities, a workshop on Neutron and X-ray Detectors was held August 1-3, 2012, in Gaithersburg, Maryland. Participants from universities, national laboratories, and commercial organizations from the United States and around the globe participated in plenary sessions, breakout groups, and joint open-discussion summary sessions. Sources have become immensely more powerful and are now brighter (more particles focused onto the sample per second) and more precise (higher spatial, spectral, and temporal resolution). To fully utilize these source advances, detectors must become faster, more efficient, and more discriminating. In supporting the mission of today’s cutting-edge neutron and X-ray sources, the workshop identified six detector research challenges

Nanocrystals Technology for Pharmaceutical Science.

Science.gov (United States)

Cheng, Zhongyao; Lian, Yumei; Kamal, Zul; Ma, Xin; Chen, Jianjun; Zhou, Xinbo; Su, Jing; Qiu, Mingfeng

2018-05-17

Nanocrystals technology is a promising method for improving the dissolution rate and enhancing the bioavailability of poorly soluble drugs. In recent years, it has been developing rapidly and applied to drug research and engineering. Nanocrystal drugs can be formulated into various dosage forms. This review mainly focused on the nanocrystals technology and its application in pharmaceutical science. Firstly, different preparation methods of nanocrystal technology and the characterization of nanocrystal drugs are briefly described. Secondly, the application of nanocrystals technology in pharmaceutical science is mainly discussed followed by the introduction of sustained release formulations. Then, the scaling up process, marketed nanocrystal drug products and regulatory aspects about nanodrugs are summarized. Finally, the specific challenges and opportunities of nanocrystals technology for pharmaceutical science are summarized and discussed. This review will provide a comprehensive guide for scientists and engineers in the field of pharmaceutical science and biochemical engineering. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Successful Climate Science Communication Strategies

Science.gov (United States)

Sinclair, P.

2016-12-01

In the past decade, efforts to communicate the facts of global change have not successfully moved political leaders and the general public to action. In response, a number of collaborative efforts between scientists and professional communicators, writers, journalists, bloggers, filmmakers, artists and others have arisen seeking to bridge that gap. As a result, a new cadre of science-literate communicators, and media-savvy scientists have made themselves visible across diverse mainstream, traditional, and social media outlets. Because of these collaborations, in recent years, misinformation, and disinformation have been successfully met with accurate and credible rebuttals within a single news cycle.Examples of these efforts is the Dark Snow Project, a science/communication collaboration focusing initially on accelerated arctic melt and sea level rise, and the Climate Science Rapid Response team, which matches professional journalists with appropriate science experts in order to respond within a single news cycle to misinformation or misunderstandings about climate science.The session will discuss successful examples and suggest creative approaches for the future.

First results from the high-brightness x-ray spectroscopy beamline at ALS

Energy Technology Data Exchange (ETDEWEB)

Perera, R.C.C.; Ng, W.; Jones, G. [Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range, designed to achieve the goal of high brightness at the sample for use in the X-ray Atomic and Molecular Spectroscopy (XAMS) science, surface and interface science, biology and x-ray optical development programs at ALS. X-ray absorption and time of flight photo emission measurements in 2 - 5 keV photon energy in argon along with the flux, resolution, spot size and stability of the beamline will be discussed. Prospects for future XAMS measurements will also be presented.

Benchtop phase-contrast X-ray imaging

Energy Technology Data Exchange (ETDEWEB)

Gundogdu, O. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)], E-mail: o.gundogdu@surrey.ac.uk; Nirgianaki, E.; Che Ismail, E.; Jenneson, P.M.; Bradley, D.A. [Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

2007-12-15

Clinical radiography has traditionally been based on contrast obtained from absorption when X-rays pass through the body. The contrast obtained from traditional radiography can be rather poor, particularly when it comes to soft tissue. A wide range of media of interest in materials science, biology and medicine exhibit very weak absorption contrast, but they nevertheless produce significant phase shifts with X-rays. The use of phase information for imaging purposes is therefore an attractive prospect. Some of the X-ray phase-contrast imaging methods require highly monochromatic plane wave radiation and sophisticated X-ray optics. However, the propagation-based phase-contrast imaging method adapted in this paper is a relatively simple method to implement, essentially requiring only a microfocal X-ray tube and electronic detection. In this paper, we present imaging results obtained from two different benchtop X-ray sources employing the free space propagation method. X-ray phase-contrast imaging provides higher contrast in many samples, including biological tissues that have negligible absorption contrast.

The Effects of Annealing Temperatures on Composition and Strain in Si x Ge1-x Obtained by Melting Growth of Electrodeposited Ge on Si (100).

Science.gov (United States)

Abidin, Mastura Shafinaz Zainal; Morshed, Tahsin; Chikita, Hironori; Kinoshita, Yuki; Muta, Shunpei; Anisuzzaman, Mohammad; Park, Jong-Hyeok; Matsumura, Ryo; Mahmood, Mohamad Rusop; Sadoh, Taizoh; Hashim, Abdul Manaf

2014-02-24

The effects of annealing temperatures on composition and strain in Si x Ge 1- x , obtained by rapid melting growth of electrodeposited Ge on Si (100) substrate were investigated. Here, a rapid melting process was performed at temperatures of 1000, 1050 and 1100 °C for 1 s. All annealed samples show single crystalline structure in (100) orientation. A significant appearance of Si-Ge vibration mode peak at ~400 cm -1 confirms the existence of Si-Ge intermixing due to out-diffusion of Si into Ge region. On a rapid melting process, Ge melts and reaches the thermal equilibrium in short time. Si at Ge/Si interface begins to dissolve once in contact with the molten Ge to produce Si-Ge intermixing. The Si fraction in Si-Ge intermixing was calculated by taking into account the intensity ratio of Ge-Ge and Si-Ge vibration mode peaks and was found to increase with the annealing temperatures. It is found that the strain turns from tensile to compressive as the annealing temperature increases. The Si fraction dependent thermal expansion coefficient of Si x Ge 1- x is a possible cause to generate such strain behavior. The understanding of compositional and strain characteristics is important in Ge/Si heterostructure as these properties seem to give significant effects in device performance.

Development of a multi-lane X-ray mirror providing variable beam sizes

Energy Technology Data Exchange (ETDEWEB)

Laundy, D., E-mail: david.laundy@diamond.ac.uk; Sawhney, K.; Nistea, I.; Alcock, S. G.; Pape, I.; Sutter, J.; Alianelli, L.; Evans, G. [Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot OX11 0DE (United Kingdom)

2016-05-15

Grazing incidence mirrors are used on most X-ray synchrotron beamlines to focus, collimate or suppress harmonics. Increasingly beamline users are demanding variable beam shapes and sizes at the sample position. We have now developed a new concept to rapidly vary the beam size and shape of a focused X-ray beam. The surface of an elliptically figured mirror is divided into a number of laterally separated lanes, each of which is given an additional longitudinal height profile calculated to shape the X-ray beam to a top-hat profile in the focal plane. We have now fabricated two prototype mirrors and present the results of metrology tests and measurements made with one of the mirrors focusing the X-rays on a synchrotron beamline. We envisage that such mirrors could be widely applied to rapid beam-size switching on many synchrotron beamlines.

The Virtual GloveboX (VGX: a Semi-immersive Virtual Environment for Training Astronauts in Life Sciences Experiments

Directory of Open Access Journals (Sweden)

I. Alexander Twombly

2004-06-01

Full Text Available The International Space Station will soon provide an unparalleled research facility for studying the near- and longer-term effects of microgravity on living systems. Using the Space Station Glovebox Facility - a compact, fully contained reach-in environment - astronauts will conduct technically challenging life sciences experiments. Virtual environment technologies are being developed at NASA Ames Research Center to help realize the scientific potential of this unique resource by facilitating the experimental hardware and protocol designs and by assisting the astronauts in training. The "Virtual GloveboX" (VGX integrates high-fidelity graphics, force-feedback devices and real-time computer simulation engines to achieve an immersive training environment. Here, we describe the prototype VGX system, the distributed processing architecture used in the simulation environment, and modifications to the visualization pipeline required to accommodate the display configuration.

A Direct TeX-to-Braille Transcribing Method

Science.gov (United States)

Papasalouros, Andreas; Tsolomitis, Antonis

2017-01-01

The TeX/LaTeX typesetting system is the most wide-spread system for creating documents in Mathematics and Science. However, no reliable tool exists to this day for automatically transcribing documents from the above formats into Braille/Nemeth code. Thus, visually impaired students of related fields do not have access to the bulk of study material…

X-ray trace element analysis with positive ion beams

International Nuclear Information System (INIS)

Davis, R.H.

1973-01-01

A new trace element analysis having the advantage that many elements may be detected in a single measurement, based on positive charged particle induced X-ray florescence and on the production of X-rays by heavy ions, is described. Because of the large cross-sections for the production of discrete X-ray and the low yield of continuum radiation, positive charged particle X-ray florescence is a competitive, fast, analytic tool. In the experiment a beam of positive charged particles from an accelerator was directed toward a target. X-rays induced by the bombardment were detected by a Si(Li) detector the ouput from which was amplified and sorted in a multichannel analyzer. For rapid data handling and analysis, the multichannel analyzer or ADC unit was connected to an on-line computer. A large variety of targets prepared in collaboration with the oceanographers have been studied and spectra obtained for different particles having the same velocity are presented to show that the yield of discrete X-rays increases at least as rapidly as Z 2 . While protons of several MeV appear to be already competitive further advantage may be gained by heavy ions at lower energies since the continuum is reduced while the peak ''signals'' retain strength due to the Z 2 dependence. (S.B.)

Rapid Synthesis of Highly Monodisperse Au x Ag 1− x Alloy Nanoparticles via a Half-Seeding Approach

KAUST Repository

Chng, Ting Ting

2011-05-03

Gold-silver alloy AuxAg1-x is an important class of functional materials promising new applications across a wide array of technological fields. In this paper, we report a fast and facile synthetic protocol for preparation of highly monodisperse AuxAg1-x alloy nanoparticles in the size range of 3-6 nm. The precursors employed in this work are M(I)-alkanethiolates (M = Au and Ag), which can be easily prepared by mixing common chemicals such as HAuCl4 or AgNO3 with alkanethiols at room temperature. In this half-seeding approach, one of the M(I)-alkanethiolates is first heated and reduced in oleylamine solvent, and freshly formed metal clusters will then act as premature seeds on which both the first and second metals (from M(I)-alkanethiolates, M = Au and Ag) can grow accordingly without additional nucleation and thus achieve high monodispersity for product alloy nanoparticles. Unlike in other prevailing methods, both Au and Ag elements present in these solid precursors are in the same monovalent state and have identical supramolecular structures, which may lead to a more homogeneous reduction and complete interdiffusion at elevated reaction temperatures. When the M(I)-alkanethiolates are reduced to metallic forms, the detached alkanethiolate ligands will serve as capping agent to control the growth. More importantly, composition, particle size, and optical properties of AuxAg1-x alloy nanoparticles can be conveniently tuned with this approach. The optical limiting properties of the prepared particles have also been investigated at 532 and 1064 nm using 7 ns laser pulses, which reveals that the as-prepared alloy nanoparticles exhibit outstanding broadband optical limiting properties with low thresholds. © 2011 American Chemical Society.

Rapid mental computation system as a tool for algorithmic thinking of elementary school students development

OpenAIRE

Ziatdinov, Rushan; Musa, Sajid

2013-01-01

In this paper, we describe the possibilities of using a rapid mental computation system in elementary education. The system consists of a number of readily memorized operations that allow one to perform arithmetic computations very quickly. These operations are actually simple algorithms which can develop or improve the algorithmic thinking of pupils. Using a rapid mental computation system allows forming the basis for the study of computer science in secondary school.

Exploring the Early Structure of a Rapidly Decompressed Particle Bed

Science.gov (United States)

Zunino, Heather; Adrian, R. J.; Clarke, Amanda; Johnson, Blair; Arizona State University Collaboration

2017-11-01

Rapid expansion of dense, pressurized beds of fine particles subjected to rapid reduction of the external pressure is studied in a vertical shock tube. A near-sonic expansion wave impinges on the particle bed-gas interface and rapidly unloads the particle bed. A high-speed video camera captures events occurring during bed expansion. The particle bed does not expand homogeneously, but breaks down into horizontal slabs and then transforms into a cellular-type structure. There are several key parameters that affect the particle bed evolution, including particle size and initial bed height. Analyses of this bed structure evolution from experiments with varying particle sizes and initial bed heights is presented. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science and Academic Alliance Program, under Contract No. DE-NA0002378.

Energy-dispersive X-ray fluorescence – A tool for interdisciplinary ...

Indian Academy of Sciences (India)

Keywords. Energy-dispersive X-ray fluorescence; trace elements; oral cancer; biomonitoring; air pollution. Abstract. Trace elements have been at the focus of attention for decades with considerable emphasis on their role in biology and biomedical sciences, environmental sciences, geology, archaeology and material ...

Advancing the science of Forest Hydrology

Science.gov (United States)

Devendra M. Amatya; R. Wayne Skaggs; Carl C. Trettin

2009-01-01

For more than a century, agricultural and biological engineers have provided major advances in science, engineering, and technology to increase food and fiber production to meet the demands of a rapidly growing global population. The land base for these technological advances has...

AXSIS: Exploring the frontiers in attosecond X-ray science, imaging and spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Kärtner, F.X., E-mail: franz.kaertner@cfel.de [Center for Free-Electron Laser Science, Hamburg (Germany); Institute for Experimental Physics, University of Hamburg, Hamburg (Germany); The Hamburg Center for Ultrafast Imaging, Hamburg (Germany); DESY, Hamburg (Germany); Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA (United States); Ahr, F. [Center for Free-Electron Laser Science, Hamburg (Germany); Institute for Experimental Physics, University of Hamburg, Hamburg (Germany); DESY, Hamburg (Germany); Max Planck Institute for the Structure and Dynamics of Matter, Hamburg (Germany); Calendron, A.-L. [Center for Free-Electron Laser Science, Hamburg (Germany); Institute for Experimental Physics, University of Hamburg, Hamburg (Germany); The Hamburg Center for Ultrafast Imaging, Hamburg (Germany); DESY, Hamburg (Germany); Çankaya, H. [Center for Free-Electron Laser Science, Hamburg (Germany); The Hamburg Center for Ultrafast Imaging, Hamburg (Germany); DESY, Hamburg (Germany); Carbajo, S. [Center for Free-Electron Laser Science, Hamburg (Germany); Institute for Experimental Physics, University of Hamburg, Hamburg (Germany); DESY, Hamburg (Germany); Chang, G.; Cirmi, G. [Center for Free-Electron Laser Science, Hamburg (Germany); The Hamburg Center for Ultrafast Imaging, Hamburg (Germany); DESY, Hamburg (Germany); Dörner, K. [Center for Free-Electron Laser Science, Hamburg (Germany); DESY, Hamburg (Germany); Dorda, U. [DESY, Hamburg (Germany); Fallahi, A. [Center for Free-Electron Laser Science, Hamburg (Germany); DESY, Hamburg (Germany); Hartin, A. [Center for Free-Electron Laser Science, Hamburg (Germany); Institute for Experimental Physics, University of Hamburg, Hamburg (Germany); DESY, Hamburg (Germany); Hemmer, M. [Center for Free-Electron Laser Science, Hamburg (Germany); DESY, Hamburg (Germany); and others

2016-09-01

X-ray crystallography is one of the main methods to determine atomic-resolution 3D images of the whole spectrum of molecules ranging from small inorganic clusters to large protein complexes consisting of hundred-thousands of atoms that constitute the macromolecular machinery of life. Life is not static, and unravelling the structure and dynamics of the most important reactions in chemistry and biology is essential to uncover their mechanism. Many of these reactions, including photosynthesis which drives our biosphere, are light induced and occur on ultrafast timescales. These have been studied with high time resolution primarily by optical spectroscopy, enabled by ultrafast laser technology, but they reduce the vast complexity of the process to a few reaction coordinates. In the AXSIS project at CFEL in Hamburg, funded by the European Research Council, we develop the new method of attosecond serial X-ray crystallography and spectroscopy, to give a full description of ultrafast processes atomically resolved in real space and on the electronic energy landscape, from co-measurement of X-ray and optical spectra, and X-ray diffraction. This technique will revolutionize our understanding of structure and function at the atomic and molecular level and thereby unravel fundamental processes in chemistry and biology like energy conversion processes. For that purpose, we develop a compact, fully coherent, THz-driven attosecond X-ray source based on coherent inverse Compton scattering off a free-electron crystal, to outrun radiation damage effects due to the necessary high X-ray irradiance required to acquire diffraction signals. This highly synergistic project starts from a completely clean slate rather than conforming to the specifications of a large free-electron laser (FEL) user facility, to optimize the entire instrumentation towards fundamental measurements of the mechanism of light absorption and excitation energy transfer. A multidisciplinary team formed by laser

SIRENA software for Athena X-IFU event reconstruction

Science.gov (United States)

Ceballos, M. T.; Cobo, B.; Peille, P.; Wilms, J.; Brand, T.; Dauser, T.; Bandler, S.; Smith, S.

2017-03-01

The X-ray Observatory Athena was proposed in April 2014 as the mission to implement the science theme "The Hot and Energetic Universe" selected by ESA for L2 (the second Large-class mission in ESA’s Cosmic Vision science programme). One of the two X-ray detectors designed to be onboard Athena is X-IFU, a cryogenic microcalorimeter based on Transition Edge Sensor (TES) technology that will provide spatially resolved high-resolution spectroscopy. X-IFU will be developed by an international consortium led by IRAP (PI), SRON (co-PI) and IAPS/INAF (co-PI) and involving ESA Member States, Japan and the United States. In Spain, IFCA (CSIC-UC) has an anticipated contribution to X-IFU through the Digital Readout Electronics (DRE) unit, in particular in the Event Processor Subsystem. For this purpose and in collaboration with the Athena end-to-end simulations team, we are currently developing the SIRENA package as part of the publicly available SIXTE end-to-end simulator. SIRENA comprises a set of processing algorithms aimed at recognizing, from a noisy signal, the intensity pulses generated by the absorption of the X-ray photons, to lately reconstruct their energy, position and arrival time. This poster describes the structure of the package and the different algorithms currently implemented as well as their comparative performance in the energy resolution achieved in the reconstruction of the instrument events.

Amorphous-to-crystalline transition in Ge{sub 8}Sb{sub (2-x)}Bi{sub x}Te{sub 11} phase-change materials for data recording

Energy Technology Data Exchange (ETDEWEB)

Svoboda, Roman, E-mail: roman.svoboda@upce.cz [Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice (Czech Republic); Karabyn, Vasyl [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice (Czech Republic); Málek, Jiří [Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice (Czech Republic); Frumar, Miloslav [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice (Czech Republic); Beneš, Ludvík; Vlček, Milan [Joint Laboratory of Solid State Chemistry of Institute of Macromolecular Chemistry of the Academy of Sciences of the Czech Republic v.v.i. and the University of Pardubice 532 10 Pardubice (Czech Republic)

2016-07-25

Structural and thermokinetic analyses were used to study the crystallization behavior of Ge{sub 8}Sb{sub (2-x)}Bi{sub x}Te{sub 11}thin films, promising materials for phase-change memory recording applications. By exploring the full compositional range, it was found that the Sb→Bi substitution leads to a decrease of crystallization enthalpy and activation energy of the main crystallization phase-change process. These trends were explained in terms of the changing structural ordering within the recently proposed new phase-change atomic switching mechanism. All of the compositions exhibited very similar transformation kinetics, confirming the uniformity of the phase-change mechanisms involved. It was further shown that rapid energy delivery achieved during heating, in the case of all investigated materials, leads to a transition from the classical nucleation/growth-based formation of 3D crystallites towards an autocatalytic phase-change process with an enormously increased speed of crystallization. Rapidity of the crystallization process was quantified for all of the studied compositions based on a novel Index of Crystallization Rapidity criterion – the results provided by this criterion showed that the highest crystallization speed was produced by the Ge{sub 8}Sb{sub 0.8}Bi{sub 1.2}Te{sub 11} composition, which therefore from this point of view appears to be a suitable candidate for the new generation of phase-change memory recording devices. - Highlights: • Crystallization behavior of Ge{sub 8}Sb{sub (2-x)}Bi{sub x}Te{sub 11} thin films was studied by DSC. • Sb → Bi substitution leads to a decrease of crystallization enthalpy and activation energy. • All compositions exhibited very similar transformation kinetics. • Rapidity of the crystallization process was quantified for the studied compositions. • Highest crystallization speed was produced by the Ge{sub 8}Sb{sub 0.8}Bi{sub 1.2}Te{sub 11} composition.

LOBSTER - New Space X-Ray telescopes

International Nuclear Information System (INIS)

Hudec, R.; Pina, L.; Simon, V.; Sveda, L.; Inneman, A.; Semencova, V.; Skulinova, M.

2007-01-01

We discuss the technological and scientific aspects of fully innovative very wide-field X-ray telescopes with high sensitivity. The prototypes of Lobster telescopes designed, developed and tested are very promising, allowing the proposals for space projects with very wide-field Lobster Eye X-ray optics to be considered for the first time. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study of various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. For example, the Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science

Science and Technology Review January/February 2011

Energy Technology Data Exchange (ETDEWEB)

Blobaum, K J

2010-11-22

This month's issue has the following articles: (1) World's Most Intense X-Ray Laser Focuses on Livermore Science - Commentary by William H. Goldstein; (2) Groundbreaking Science with the World's Brightest X Rays - Experiments with x rays of unparalleled brightness and extremely short duration aim to reveal new information about atoms and molecules in motion; (3) From Data to Discovery - Ongoing control system enhancements at the National Ignition Facility bolster the understanding of experimental data and keep the system performing at its peak; (4) The Sun in All Its Splendor - Onboard the Solar Dynamics Observatory, Livermore-developed multilayer mirrors are enabling unprecedented full-disk, high-resolution images of the Sun; and (5) Drilling Deep into Plant Veins - A novel combination of imaging techniques is being used to understand the three-dimensional architecture of plant cell walls.

A status report on Cygnus X-1

International Nuclear Information System (INIS)

Eardley, D.M.; Lightman, A.P.; Shakura, N.I.; Shapiro, S.L.; Sunyaev, R.A.

1978-01-01

Detailed models of gas flow and X-ray production are discussed, but it is concluded that the strongest argument in favour of a black hole is that Cygnus X-1 is a compact object, and has a mass larger than that allowed for a neutron star or white dwarf. Evidence for the former feature is associated with the observation of very rapid time variability in X-rays. Evidence for the latter follows from a union of various types of observations of the Cyg X-1 star system, in which the visible star is the single-line spectroscopic binary HDE 226868, a normal supergiant. The evidence is reviewed under the following headings: geometry of the accretion flow; emission mechanism; time variability. (U.K.)

Blast-Wave Generation and Propagation in Rapidly Heated Laser-Irradiated Targets

Science.gov (United States)

Ivancic, S. T.; Stillman, C. R.; Nilson, P. M.; Solodov, A. A.; Froula, D. H.

2017-10-01

Time-resolved extreme ultraviolet (XUV) spectroscopy was used to study the creation and propagation of a >100-Mbar blast wave in a target irradiated by an intense (>1018WWcm2 cm2) laser pulse. Blast waves provide a platform to generate immense pressures in the laboratory. A temporal double flash of XUV radiation was observed when viewing the rear side of the target, which is attributed to the emergence of a blast wave following rapid heating by a fast-electron beam generated from the laser pulse. The time-history of XUV emission in the photon energy range of 50 to 200 eV was recorded with an x-ray streak camera with 7-ps temporal resolution. The heating and expansion of the target was simulated with an electron transport code coupled to 1-D radiation-hydrodynamics simulations. The temporal delay between the two flashes measured in a systematic study of target thickness and composition was found to evolve in good agreement with a Sedov-Taylor blast-wave solution. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944 and Department of Energy Office of Science Award Number DE-SC-0012317.

NST and NST integration: nuclear science and technique and nano science and technique

International Nuclear Information System (INIS)

Zhao Yuliang; Chai Zhifang; Liu Yuanfang

2008-01-01

Nuclear science is considered as a big science and also the frontier in the 20 th century, it developed many big scientific facilities and many technique platforms (e.g., nuclear reactor, synchrotron radiation, accelerator, etc.) Nuclear Science and Technology (NST) provide us with many unique tools such as neutron beams, electron beams, gamma rays, alpha rays, beta rays, energetic particles, etc. These are efficient and essential probes for studying many technique and scientific issues in the fields of new materials, biological sciences, environmental sciences, life sciences, medical science, etc. Nano Science and Technology (NST) is a newly emerging multidisciplinary science and the frontier in the 21 st century, it is expected to dominate the technological revolution in diverse aspects of our life. It involves diverse fields such as nanomaterials, nanobiological sciences, environmental nanotechnology, nanomedicine, etc. nanotechnology was once considered as a futuristic science with applications several decades in the future and beyond. But, the rapid development of nanotechnology has broken this prediction. For example, diverse types of manufactured nanomaterials or nanostructures have been currently utilized in industrial products, semiconductors, electronics, stain-resistant clothing, ski wax, catalysts, other commodity products such as food, sunscreens, cosmetics, automobile parts, etc., to improve their performance of previous functions, or completely create novel functions. They will also be increasingly utilized in medicines for purposes of clinic therapy, diagnosis, and drug delivery. In the talk, we will discuss the possibility of NST-NST integration: how to apply the unique probes of advanced radiochemical and nuclear techniques in nanoscience and nanotechnology. (authors)

Rapid-swept CW cavity ring-down laser spectroscopy for carbon isotope analysis

International Nuclear Information System (INIS)

Tomita, Hideki; Watanabe, Kenichi; Takiguchi, Yu; Kawarabayashi, Jun; Iguchi, Tetsuo

2006-01-01

With the aim of developing a portable system for an in field isotope analysis, we investigate an isotope analysis based on rapid-swept CW cavity ring-down laser spectroscopy, in which the concentration of a chemical species is derived from its photo absorbance. Such a system can identify the isotopomer and still be constructed as a quite compact system. We have made some basic experimental measurements of the overtone absorption lines of carbon dioxide ( 12 C 16 O 2 , 13 C 16 O 2 ) by rapid-swept cavity ring-down spectroscopy with a CW infrared diode laser at 6,200 cm -1 (1.6 μm). The isotopic ratio has been obtained as (1.07±0.13)x10 -2 , in good agreement with the natural abundance within experimental uncertainty. The detection sensitivity in absorbance has been estimated to be 3x10 -8 cm -1 . (author)

Miniaturized High-Speed Modulated X-Ray Source

Science.gov (United States)

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.

X-ray microprobe for the microcharacterization of materials

International Nuclear Information System (INIS)

Sparks, C.J.; Ice, G.E.

1988-01-01

The unique properties of x rays offer many advantages over those of electrons and other charged particles for the microcharacterization of materials. X rays are more efficient in exciting characteristic x-ray fluorescence and produce higher fluorescent signal-to-background ratios than obtained with electrons. Such x-ray microprobes will also produce unprecedentedly low levels of detection in diffraction, EXAFS, Auger, and photoelectron spectroscopies for structural and chemical characterization and elemental identification. These major improvements in microcharacterization capabilities will have wide-ranging ramifications not only in materials science but also in physics, chemistry, geochemistry, biology, and medicine. 24 refs., 6 figs., 2 tabs

100 years of discovery of X-ray diffraction

International Nuclear Information System (INIS)

Zhang Tao

2012-01-01

X-ray diffraction was discovered by Max von Laue a hundred years ago. Later, through the work of William H. Bragg and William L. Bragg, an experimental analysis method was developed to solve the structure of molecules at the atomic level. Over the past hundred years, science and technology has been dramatically changed by X-ray diffraction analysis, which has also undergone considerable development. The recent emergence of hard X-ray free electron lasers has provided a new dimension for X-ray diffraction analysis, promising even greater progress in the fields of physics, chemistry and biology. (author)

The NHERI RAPID Facility: Enabling the Next-Generation of Natural Hazards Reconnaissance

Science.gov (United States)

Wartman, J.; Berman, J.; Olsen, M. J.; Irish, J. L.; Miles, S.; Gurley, K.; Lowes, L.; Bostrom, A.

2017-12-01

The NHERI post-disaster, rapid response research (or "RAPID") facility, headquartered at the University of Washington (UW), is a collaboration between UW, Oregon State University, Virginia Tech, and the University of Florida. The RAPID facility will enable natural hazard researchers to conduct next-generation quick response research through reliable acquisition and community sharing of high-quality, post-disaster data sets that will enable characterization of civil infrastructure performance under natural hazard loads, evaluation of the effectiveness of current and previous design methodologies, understanding of socio-economic dynamics, calibration of computational models used to predict civil infrastructure component and system response, and development of solutions for resilient communities. The facility will provide investigators with the hardware, software and support services needed to collect, process and assess perishable interdisciplinary data following extreme natural hazard events. Support to the natural hazards research community will be provided through training and educational activities, field deployment services, and by promoting public engagement with science and engineering. Specifically, the RAPID facility is undertaking the following strategic activities: (1) acquiring, maintaining, and operating state-of-the-art data collection equipment; (2) developing and supporting mobile applications to support interdisciplinary field reconnaissance; (3) providing advisory services and basic logistics support for research missions; (4) facilitating the systematic archiving, processing and visualization of acquired data in DesignSafe-CI; (5) training a broad user base through workshops and other activities; and (6) engaging the public through citizen science, as well as through community outreach and education. The facility commenced operations in September 2016 and will begin field deployments beginning in September 2018. This poster will provide an overview

A quasi-realtime x-ray microtomography system at the Advanced Photon Source

International Nuclear Information System (INIS)

DeCarlo, F.; Foster, I.; Insley, J.; Kesselman, C.; Lane, P.; Mancini, D.; McNulty, I.; Su, M.; Tieman, B.; Wang, Y.; Laszewski, G. von

1999-01-01

The combination of high-brilliance x-ray sources, fast detector systems, wide-bandwidth networks, and parallel computers can substantially reduce the time required to acquire, reconstruct, and visualize high-resolution three-dimensional tomographic datasets. A quasi-realtime computed x-ray microtomography system has been implemented at the 2-BM beamline at the Advanced Photon Source at Argonne National Laboratory. With this system, a complete tomographic data set can be collected in about 15 minutes. Immediately after each projection is obtained, it is rapidly transferred to the Mathematics and Computing Sciences Division where preprocessing and reconstruction calculations are performed concurrently with the data acquisition by a SGI parallel computer. The reconstruction results, once completed, are transferred to a visualization computer that performs the volume rendering calculations. Rendered images of the reconstructed data are available for viewing back at the beamline experiment station minutes after the data acquisition was complete. The fully pipelined data acquisition and reconstruction system also gives us the option to acquire the tomographic data set in several cycles, initially with coarse then with fine angular steps. At present the projections are acquired with a straight-ray projection imaging scheme using 5-20 keV hard x rays in either phase or amplitude contrast mode at a 1-10 pm resolution. In the future, we expect to increase the resolution of the projections to below 100 nm by using a focused x-ray beam at the 2-ID-B beamline and to reduce the combined acquisition and computation time to the 1 min scale with improvements in the detectors, network links, software pipeline, and computation algorithms

FTIR spectroscopy applications in forensic science

International Nuclear Information System (INIS)

Roux, C.; Maynard, P.; Dawson, M.

1999-01-01

Infrared spectroscopy, and especially Fourier transform infrared spectroscopy, is a well-established technique in analytical chemistry and finds widespread application in qualitative and quantitative analyses. Infrared spectra depend on the nature of the functional groups present in the analyte, and are generally complex with numerous maxima and minima. These features are useful for comparison purposes and, in most cases, the infrared spectrum of an organic compound is considered as a unique functional print of this compound (i e the infrared spectrum constitutes the chemical signature or fingerprint of an organic compound). Many inorganic substances may also be uniquely identified using infrared spectroscopy. Until recently, infrared spectroscopy was of only limited utility in forensic science, despite its high selectivity. This is because infrared spectroscopy suffered from a lack of sensitivity in its early forms. However, with the advance of modern technology this is no longer the case. The widespread use of microscope attachments, along with numerous new sampling accessories, has overcome most of the previous limitations. For example, with an infrared microscope, it is possible to focus the infrared beam, and therefore select relevant areas of the sample as small as 10 x 10 μm and achieve a measurement in situ. Such a configuration enables the rapid generation of high-resolution spectra from samples of 10 ng. Typical forensic applications include the analysis of single textile fibres, minute paint chips or smears, drugs, laser printer and photocopy toners, polymers and miscellaneous unknown substances. Here we will broadly review the most common applications of infrared spectroscopy in forensic science

X-ray and synchrotron methods in studies of cultural heritage sites

Energy Technology Data Exchange (ETDEWEB)

Koval’chuk, M. V.; Yatsishina, E. B.; Blagov, A. E.; Tereshchenko, E. Yu., E-mail: elenatereschenko@yandex.ru; Prosekov, P. A.; Dyakova, Yu. A. [National Research Centre “Kurchatov Institute” (Russian Federation)

2016-09-15

X-ray and synchrotron methods that are most widely used in studies of cultural heritage objects (including archaeological sites)—X-ray diffraction analysis, X-ray spectroscopy, and visualization techniques— have been considered. The reported examples show high efficiency and informativeness of natural science studies when solving most diverse problems of archaeology, history, the study of art, museology, etc.

X-ray and synchrotron methods in studies of cultural heritage sites

International Nuclear Information System (INIS)

Koval’chuk, M. V.; Yatsishina, E. B.; Blagov, A. E.; Tereshchenko, E. Yu.; Prosekov, P. A.; Dyakova, Yu. A.

2016-01-01

X-ray and synchrotron methods that are most widely used in studies of cultural heritage objects (including archaeological sites)—X-ray diffraction analysis, X-ray spectroscopy, and visualization techniques— have been considered. The reported examples show high efficiency and informativeness of natural science studies when solving most diverse problems of archaeology, history, the study of art, museology, etc.

X-ray phase-contrast imaging

Science.gov (United States)

Endrizzi, Marco

2018-01-01

X-ray imaging is a standard tool for the non-destructive inspection of the internal structure of samples. It finds application in a vast diversity of fields: medicine, biology, many engineering disciplines, palaeontology and earth sciences are just few examples. The fundamental principle underpinning the image formation have remained the same for over a century: the X-rays traversing the sample are subjected to different amount of absorption in different parts of the sample. By means of phase-sensitive techniques it is possible to generate contrast also in relation to the phase shifts imparted by the sample and to extend the capabilities of X-ray imaging to those details that lack enough absorption contrast to be visualised in conventional radiography. A general overview of X-ray phase contrast imaging techniques is presented in this review, along with more recent advances in this fast evolving field and some examples of applications.

Low Cost Rapid Response Spacecraft, (LCRRS): A Research Project in Low Cost Spacecraft Design and Fabrication in a Rapid Prototyping Environment

Science.gov (United States)

Spremo, Stevan; Bregman, Jesse; Dallara, Christopher D.; Ghassemieh, Shakib M.; Hanratty, James; Jackson, Evan; Kitts, Christopher; Klupar, Pete; Lindsay, Michael; Ignacio, Mas;

Development of small scale soft x-ray lasers

International Nuclear Information System (INIS)

Kim, D.; Suckewer, S.; Princeton Univ., NJ; Skinner, C.H.; Voorhees, D.

1991-05-01

At present rapid progress is being made in the application of soft x-ray lasers to fields such as microscopy and microlithography. A critical factor in the range of suitable applications is the scale and hence cost of the soft x-ray lasers. At Princeton, gain at 183 angstrom has been obtained with relatively low pump laser energies (as low as 6J) in a ''portable'' small-scale soft x-ray laser system. We will also discuss aspects of data interpretation and pitfalls to be avoided in measurements of gain in such systems. 14 refs., 7 figs

Effects of X irradiation and high field electron injection of the electrical properties of rapid thermal oxides

International Nuclear Information System (INIS)

Schubert, W.K.; Seager, C.H.

1988-01-01

Rapid thermal oxidation (RTO) is a promising tool for fabricating the thin gate oxides (5 to 15 nm) that will be needed in future submicron integrated circuits, because of its inherently superior time-temperature control when compared to conventional oxidation methods. It is important to demonstrate that RTO can be used without adversely affecting the radiation hardness or high field properties of the oxide. Beyond this demonstration, rapid thermal processing makes it possible to determine more precisely how the kinetics of oxidation and post oxidation annealing affect the device properties. Information of this type should prove useful in modeling relevant defect formation mechanisms. The present paper is part of a systematic study of the effect of rapid thermal processing on the radiation and high field response of thin oxides

Rapid X-ray crystal structure analysis in few second measurements using microstrip gas chamber

CERN Document Server

Ochi, A; Tanimori, T; Ohashi, Y; Toyokawa, H; Nishi, Y; Nishi, Y; Nagayoshi, T; Koishi, S

2001-01-01

X-ray crystal structure analysis using microstrip gas chamber was successfully carried out in a measurement time within a few seconds. The continuous rotation photograph method, in which most of the diffraction peaks can be obtained within one continuous rotation of the sample crystal (without stopping or oscillation), was applied for this measurement. As an example, the structure of a single crystal of ammonium bitartrate (r=1 mm, spherical) was measured. Diffraction spots from the sample, which were sufficient to obtain crystal structure, were successfully obtained by taking only 2 s measurements with a commercially available laboratory X-ray source.

X-ray Observations of Eight Young Open Star Clusters: I ...

Indian Academy of Sciences (India)

X-ray Observations of Eight Young Open Star Clusters: I. Membership and X-ray Luminosity. Himali Bhatt, J. C. Pandey, K. P. Singh, Ram Sagar & Brijesh Kumar. J. Astrophys. Astr. 34(4), December 2013, pp. 393–429, c Indian Academy of Sciences. Supplementary Material. Supplementary Table 3 follows.

In Situ Soft X-ray Spectromicroscopy of Early Tricalcium Silicate Hydration

Directory of Open Access Journals (Sweden)

Sungchul Bae

2016-12-01

Full Text Available The understanding and control of early hydration of tricalcium silicate (C3S is of great importance to cement science and concrete technology. However, traditional characterization methods are incapable of providing morphological and spectroscopic information about in situ hydration at the nanoscale. Using soft X-ray spectromicroscopy, we report the changes in morphology and molecular structure of C3S at an early stage of hydration. In situ C3S hydration in a wet cell, beginning with induction (~1 h and acceleration (~4 h periods of up to ~8 h, was studied and compared with ex situ measurements in the deceleration period after 15 h of curing. Analysis of the near-edge X-ray absorption fine structure showed that the Ca binding energy and energy splitting of C3S changed rapidly in the early age of hydration and exhibited values similar to calcium silicate hydrate (C–S–H. The formation of C–S–H nanoseeds in the C3S solution and the development of a fibrillar C–S–H morphology on the C3S surface were visualized. Following this, silicate polymerization accompanied by C–S–H precipitation produced chemical shifts in the peaks of the main Si K edge and in multiple scattering. However, the silicate polymerization process did not significantly affect the Ca binding energy of C–S–H.

Rapid screening of monoclonal antibodies: new 'microstick' radioimmunoassay

International Nuclear Information System (INIS)

Scheinberg, D.A.; Strand, M.; Wilsnack, R.

1983-01-01

A new system for assaying monoclonal antibodies consisting of an 8 x 12 array of sticks which fits into a 96-well microtiter plate is described. Tests using virus specific monoclonal antibodies and virus proteins demonstrated sensitivity equivalent to the conventional microtiter plate assay. Antibody production, antigen specific antibody, and immunoglobulin isotypes could be measured under sterile conditions directly in the original fusion mixture wells and much greater rapidity than with the microtiter plate assay. (Auth.)

Influence of cooling rate and cerium addition on rapidly solidified Al-TM alloys

Czech Academy of Sciences Publication Activity Database

Michalcová, A.; Vojtěch, D.; Schumacher, G.; Novák, P.; Klementová, Mariana; Šerák, J.; Mudrová, M.; Valdaufová, J.

2010-01-01

Roč. 48, č. 1 (2010), s. 1-7 ISSN 0023-432X Institutional research plan: CEZ:AV0Z40320502 Keywords : rapid solidification * Al-TM * microstructure * aluminium Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.471, year: 2010

X-ray scattering studies of lanthanides magnetism

DEFF Research Database (Denmark)

McMorrow, D.; Bohr, Jakob; Gibbs, D.

1999-01-01

Interest in the applications of X-ray synchrotron radiation has grown rapidly during the last decade. At the present time, intense, ultra-bright synchrotron radiation is available on a routine basis from third-generation sources located in Europe (ESRF), North America (APS) and Japan (Spring8). T...

CubeX: The CubeSAT X-ray Telescope for Elemental Abundance Mapping of Airless Bodies and X-ray Pulsar Navigation

Science.gov (United States)

Nittler, L. R.; Hong, J.; Kenter, A.; Romaine, S.; Allen, B.; Kraft, R.; Masterson, R.; Elvis, M.; Gendreau, K.; Crawford, I.; Binzel, R.; Boynton, W. V.; Grindlay, J.; Ramsey, B.

2017-12-01

The surface elemental composition of a planetary body provides crucial information about its origin, geological evolution, and surface processing, all of which can in turn provide information about solar system evolution as a whole. Remote sensing X-ray fluorescence (XRF) spectroscopy has been used successfully to probe the major-element compositions of airless bodies in the inner solar system, including the Moon, near-Earth asteroids, and Mercury. The CubeSAT X-ray Telescope (CubeX) is a concept for a 6U planetary X-ray telescope (36U with S/C), which utilizes Miniature Wolter-I X-ray optics (MiXO), monolithic CMOS and SDD X-ray sensors for the focal plane, and a Solar X-ray Monitor (heritage from the REXIS XRF instrument on NASA's OSIRIS-REx mission). CubeX will map the surface elemental composition of diverse airless bodies by spectral measurement of XRF excited by solar X-rays. The lightweight ( 1 kg) MiXO optics provide sub-arcminute resolution with low background, while the inherently rad-hard CMOS detectors provide improved spectral resolution ( 150 eV) at 0 °C. CubeX will also demonstrate X-ray pulsar timing based deep space navigation (XNAV). Successful XNAV will enable autonomous deep navigation with little to no support from the Deep Space Network, hence lowering the operation cost for many more planetary missions. Recently selected by NASA Planetary Science Deep Space SmallSat Studies, the first CubeX concept, designed to rideshare to the Moon as a secondary spacecraft on a primary mission, is under study in collaboration with the Mission Design Center at NASA Ames Research Center. From high altitude ( 6,000 km) frozen polar circular orbits, CubeX will study > 8 regions ( 110 km) of geological interest on the Moon over one year to produce a high resolution ( 2-3 km) elemental abundance map of each region. The novel focal plane design of CubeX also allows us to evaluate the performance of absolute navigation by sequential observations of several

Cray X1 Evaluation Status Report

Energy Technology Data Exchange (ETDEWEB)

Vetter, J.S.

2004-02-09

On August 15, 2002 the Department of Energy (DOE) selected the Center for Computational Sciences (CCS) at Oak Ridge National Laboratory (ORNL) to deploy a new scalable vector supercomputer architecture for solving important scientific problems in climate, fusion, biology, nanoscale materials and astrophysics. ''This program is one of the first steps in an initiative designed to provide U.S. scientists with the computational power that is essential to 21st century scientific leadership,'' said Dr. Raymond L. Orbach, director of the department's Office of Science The Cray X1 is an attempt to incorporate the best aspects of previous Cray vector systems and massively-parallel-processing (MPP) systems into one design. Like the Cray T90, the X1 has high memory bandwidth, which is key to realizing a high percentage of theoretical peak performance. Like the Cray T3E, the X1 has a high-bandwidth, low-latency, scalable interconnect, and scalable system software. And, like the Cray SV1, the X1 leverages commodity off-the-shelf (CMOS) technology and incorporates non-traditional vector concepts, like vector caches and multi-streaming processors. In FY03, CCS procured a 256-processor Cray X1 to evaluate the processors, memory subsystem, scalability of the architecture, software environment and to predict the expected sustained performance on key DOE applications codes. The results of the micro-benchmarks and kernel benchmarks show the architecture of the Cray X1 to be exceptionally fast for most operations. The best results are shown on large problems, where it is not possible to fit the entire problem into the cache of the processors. These large problems are exactly the types of problems that are important for the DOE and ultra-scale simulation.

Development of a rapid radiochemical procedure for the separation of /sup 235m/U from 239Pu

International Nuclear Information System (INIS)

Attrep, M. Jr.; Efurd, D.W.; Roensch, F.R.

1987-01-01

We have developed a rapid radiochemical procedure for the isolation and purification of /sup 235m/U (t/sub 1/2/ = 26 minutes) from 239 Pu samples up to 250 mg. Purpose of developing the procedure was to measure the thermal neutron fission cross section of the isomeric meta state of 235 U. We used rapid small-scale anion exchange columns that absorbed uranium in concentrated HBr but did not absorb plutonium. Uranium was easily eluted with very dilute HF. The separation time required 25 to 35 minutes. We were able to attain a separation factor of uranium from plutonium of approximately 1 x 10 10 with samples ranging from 1 x 10 10 to 3 x 10 11 . The ratio of the fission cross sections for the meta to ground state was measured to be 1.42. 4 figs., 1 tab

Einstein X-ray survey of the Pleiades - The dependence of X-ray emission on stellar age

Science.gov (United States)

Micela, G.; Sciortino, S.; Serio, S.; Vaiana, G. S.; Bookbinder, J.; Golub, L.; Harnden, F. R., Jr.; Rosner, R.

1985-01-01

The data obtained with two pointed observations of 1 deg by 1 deg fields of the Pleiades region have been analyzed, and the results are presented. The maximum-likelihood X-ray luminosity functions for the Pleiades G and K stars in the cluster are derived, and it is shown that, for the G stars, the Pleiades X-ray luminosity function is significantly brighter than the corresponding function for Hyades G dwarf stars. This finding indicates a dependence of X-ray luminosity on stellar age, which is confirmed by comparison of the same data with median X-ray luminosities of pre-main sequence and local disk population dwarf G stars. It is suggested that the significantly larger number of bright X-ray sources associated with G stars than with K stars, the lack of detection of M stars, and the relatively rapid rotation of the Pleiades K stars can be explained in terms of the onset of internal differential rotation near the convective envelope-radidative core interface after the spin-up phase during evolution to the main sequence.

The medical science DMZ: a network design pattern for data-intensive medical science.

Science.gov (United States)

Peisert, Sean; Dart, Eli; Barnett, William; Balas, Edward; Cuff, James; Grossman, Robert L; Berman, Ari; Shankar, Anurag; Tierney, Brian

2017-10-06

We describe a detailed solution for maintaining high-capacity, data-intensive network flows (eg, 10, 40, 100 Gbps+) in a scientific, medical context while still adhering to security and privacy laws and regulations. High-end networking, packet-filter firewalls, network intrusion-detection systems. We describe a "Medical Science DMZ" concept as an option for secure, high-volume transport of large, sensitive datasets between research institutions over national research networks, and give 3 detailed descriptions of implemented Medical Science DMZs. The exponentially increasing amounts of "omics" data, high-quality imaging, and other rapidly growing clinical datasets have resulted in the rise of biomedical research "Big Data." The storage, analysis, and network resources required to process these data and integrate them into patient diagnoses and treatments have grown to scales that strain the capabilities of academic health centers. Some data are not generated locally and cannot be sustained locally, and shared data repositories such as those provided by the National Library of Medicine, the National Cancer Institute, and international partners such as the European Bioinformatics Institute are rapidly growing. The ability to store and compute using these data must therefore be addressed by a combination of local, national, and industry resources that exchange large datasets. Maintaining data-intensive flows that comply with the Health Insurance Portability and Accountability Act (HIPAA) and other regulations presents a new challenge for biomedical research. We describe a strategy that marries performance and security by borrowing from and redefining the concept of a Science DMZ, a framework that is used in physical sciences and engineering research to manage high-capacity data flows. By implementing a Medical Science DMZ architecture, biomedical researchers can leverage the scale provided by high-performance computer and cloud storage facilities and national high

Cell survival studies using ultrasoft x rays

International Nuclear Information System (INIS)

Schillaci, M.E.; Raju, M.R.; Carpenter, S.; Cornforth, M.; Wilder, M.

1987-01-01

Cell survival was studied for V79 hamster, 10T1/2 mouse, and human skin fibroblast cell lines, using carbon K (0.28 keV), copper K (8.0 keV), and 250 kVp x rays. Because of the rapid attenuation of the carbon x rays, cellular dimensions at the time of exposure were measured using optical and electron microscopy, and frequency distributions of mean dose absorbed by the cell nucleus were obtained. The results indicate that the differences in cell killing between ultra-soft and hard x rays may depend on the nuclear thickness of the cells. Studies of the effects of hypoxia on V79 and 10T1/2 cells using carbon K, aluminum K (1.5 keV), and copper K x rays show decreasing OER values with decreasing x-ray energy and no difference between the two cell lines. Age response studies with V79 cells show similar cell-cycle variation of survival for carbon K and aluminum K x rays as for hard x rays

Laboratory-size three-dimensional x-ray microscope with Wolter type I mirror optics and an electron-impact water window x-ray source

Energy Technology Data Exchange (ETDEWEB)

Ohsuka, Shinji, E-mail: ohsuka@crl.hpk.co.jp [Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, 434-8601 (Japan); The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsu-cho, Nishi-ku, Hamamatsu-City, 431-1202 (Japan); Ohba, Akira; Onoda, Shinobu; Nakamoto, Katsuhiro [Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, 434-8601 (Japan); Nakano, Tomoyasu [Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, 434-8601 (Japan); Ray-Focus Co. Ltd., 6009 Shinpara, Hamakita-ku, Hamamatsu-City, 434-0003 (Japan); Miyoshi, Motosuke; Soda, Keita; Hamakubo, Takao [Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan)

2014-09-15

We constructed a laboratory-size three-dimensional water window x-ray microscope that combines wide-field transmission x-ray microscopy with tomographic reconstruction techniques, and observed bio-medical samples to evaluate its applicability to life science research fields. It consists of a condenser and an objective grazing incidence Wolter type I mirror, an electron-impact type oxygen Kα x-ray source, and a back-illuminated CCD for x-ray imaging. A spatial resolution limit of around 1.0 line pairs per micrometer was obtained for two-dimensional transmission images, and 1-μm scale three-dimensional fine structures were resolved.

Laboratory-size three-dimensional x-ray microscope with Wolter type I mirror optics and an electron-impact water window x-ray source.

Science.gov (United States)

Ohsuka, Shinji; Ohba, Akira; Onoda, Shinobu; Nakamoto, Katsuhiro; Nakano, Tomoyasu; Miyoshi, Motosuke; Soda, Keita; Hamakubo, Takao

2014-09-01

We constructed a laboratory-size three-dimensional water window x-ray microscope that combines wide-field transmission x-ray microscopy with tomographic reconstruction techniques, and observed bio-medical samples to evaluate its applicability to life science research fields. It consists of a condenser and an objective grazing incidence Wolter type I mirror, an electron-impact type oxygen Kα x-ray source, and a back-illuminated CCD for x-ray imaging. A spatial resolution limit of around 1.0 line pairs per micrometer was obtained for two-dimensional transmission images, and 1-μm scale three-dimensional fine structures were resolved.

Content Analysis of Life Exhibitions in Japanese Science Museums and Centres

Science.gov (United States)

Kazama, Tomoko; Ogawa, Masakata

2015-01-01

Life exhibitions in Japanese science museums (SMs) face difficulties in coping with rapid progress in the life sciences owing to certain constraints around the frequency of exhibit renovations, and the Japanese indigenous understanding of the natural world (Shizen) that Japanese visitors unconsciously bring with them. To what extent do current…

Design of a radiation hard silicon pixel sensor for X-ray science

Energy Technology Data Exchange (ETDEWEB)

Schwandt, Joern

2014-06-15

At DESY Hamburg the European X-ray Free-Electron Laser (EuXFEL) is presently under construction. The EuXFEL has unique properties with respect to X-ray energy, instantaneous intensity, pulse length, coherence and number of pulses/sec. These properties of the EuXFEL pose very demanding requirements for imaging detectors. One of the detector systems which is currently under development to meet these challenges is the Adaptive Gain Integrating Pixel Detector, AGIPD. It is a hybrid pixel-detector system with 1024 x 1024 p{sup +} pixels of dimensions 200 μm x 200 μm, made of 16 p{sup +}nn{sup +}- silicon sensors, each with 10.52 cm x 2.56 cm sensitive area and 500 μm thickness. The particular requirements for the AGIPD are a separation between noise and single photons down to energies of 5 keV, more than 10{sup 4} photons per pixel for a pulse duration of less than 100 fs, negligible pile-up at the EuXFEL repetition rate of 4.5 MHz, operation for X-ray doses up to 1 GGy, good efficiency for X-rays with energies between 5 and 20 keV, and minimal inactive regions at the edges. The main challenge in the sensor design is the required radiation tolerance and high operational voltage, which is required to reduce the so-called plasma effect. This requires a specially optimized sensor. The X-ray radiation damage results in a build-up of oxide charges and interface traps which lead to a reduction of the breakdown voltage, increased leakage current, increased interpixel capacitances and charge losses. Extensive TCAD simulations have been performed to understand the impact of X-ray radiation damage on the detector performance and optimize the sensor design. To take radiation damage into account in the simulation, radiation damage parameters have been determined on MOS capacitors and gate-controlled diodes as function of dose. The optimized sensor design was fabricated by SINTEF. Irradiation tests on test structures and sensors show that the sensor design is radiation hard and

The SpeX Prism Library for Ultracool Dwarfs: A Resource for Stellar, Exoplanet and Galactic Science and Student-Led Research

Science.gov (United States)

Burgasser, Adam

The NASA Infrared Telescope Facility's (IRTF) SpeX spectrograph has been an essential tool in the discovery and characterization of ultracool dwarf (UCD) stars, brown dwarfs and exoplanets. Over ten years of SpeX data have been collected on these sources, and a repository of low-resolution (R 100) SpeX prism spectra has been maintained by the PI at the SpeX Prism Spectral Libraries website since 2008. As the largest existing collection of NIR UCD spectra, this repository has facilitated a broad range of investigations in UCD, exoplanet, Galactic and extragalactic science, contributing to over 100 publications in the past 6 years. However, this repository remains highly incomplete, has not been uniformly calibrated, lacks sufficient contextual data for observations and sources, and most importantly provides no data visualization or analysis tools for the user. To fully realize the scientific potential of these data for community research, we propose a two-year program to (1) calibrate and expand existing repository and archival data, and make it virtual-observatory compliant; (2) serve the data through a searchable web archive with basic visualization tools; and (3) develop and distribute an open-source, Python-based analysis toolkit for users to analyze the data. These resources will be generated through an innovative, student-centered research model, with undergraduate and graduate students building and validating the analysis tools through carefully designed coding challenges and research validation activities. The resulting data archive, the SpeX Prism Library, will be a legacy resource for IRTF and SpeX, and will facilitate numerous investigations using current and future NASA capabilities. These include deep/wide surveys of UCDs to measure Galactic structure and chemical evolution, and probe UCD populations in satellite galaxies (e.g., JWST, WFIRST); characterization of directly imaged exoplanet spectra (e.g., FINESSE), and development of low

Ada and the rapid development lifecycle

Science.gov (United States)

Deforrest, Lloyd; Gref, Lynn

1991-01-01

JPL is under contract, through NASA, with the US Army to develop a state-of-the-art Command Center System for the US European Command (USEUCOM). The Command Center System will receive, process, and integrate force status information from various sources and provide this integrated information to staff officers and decision makers in a format designed to enhance user comprehension and utility. The system is based on distributed workstation class microcomputers, VAX- and SUN-based data servers, and interfaces to existing military mainframe systems and communication networks. JPL is developing the Command Center System utilizing an incremental delivery methodology called the Rapid Development Methodology with adherence to government and industry standards including the UNIX operating system, X Windows, OSF/Motif, and the Ada programming language. Through a combination of software engineering techniques specific to the Ada programming language and the Rapid Development Approach, JPL was able to deliver capability to the military user incrementally, with comparable quality and improved economies of projects developed under more traditional software intensive system implementation methodologies.

Association of nerve growth factor receptors with the triton X-100 cytoskeleton of PC12 cells

International Nuclear Information System (INIS)

Vale, R.D.; Ignatius, M.J.; Shooter, E.M.

1985-01-01

Triton X-100 solubilizes membranes of PC12 cells and leaves behind a nucleus and an array of cytoskeletal filaments. Nerve growth factor (NGF) receptors are associated with this Triton X-100-insoluble residue. Two classes of NGF receptors are found on PC12 cells which display rapid and slow dissociating kinetics. Although rapidly dissociating binding is predominant (greater than 75%) in intact cells, the majority of binding to the Triton X-100 cytoskeleton is slowly dissociating (greater than 75%). Rapidly dissociating NGF binding on intact cells can be converted to a slowly dissociating form by the plant lectin wheat germ agglutinin (WGA). This lectin also increases the number of receptors which associate with the Triton X-100 cytoskeleton by more than 10-fold. 125 I-NGF bound to receptors can be visualized by light microscopy autoradiography in Triton X-100-insoluble residues of cell bodies, as well as growth cones and neurites. The WGA-induced association with the cytoskeleton, however, is not specific for the NGF receptor. Concentrations of WGA which change the Triton X-100 solubility of membrane glycoproteins are similar to those required to alter the kinetic state of the NGF receptor. Both events may be related to the crossbridging of cell surface proteins induced by this multivalent lectin

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

International Nuclear Information System (INIS)

Barty, C.P.J.

2000-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2000-03-01

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

Pushing the Boundaries of X-ray Grating Spectroscopy in a Suborbital Rocket

Science.gov (United States)

McEntaffer, Randall L.; DeRoo, Casey; Schultz, Ted; Zhang, William W.; Murray, Neil J.; O'Dell, Stephen; Cash, Webster

2013-01-01

Developments in grating spectroscopy are paramount for meeting the soft X-ray science goals of future NASA X-ray Observatories. While developments in the laboratory setting have verified the technical feasibility of using off-plane reflection gratings to reach this goal, flight heritage is a key step in the development process toward large missions. To this end we have developed a design for a suborbital rocket payload employing an Off-Plane X-ray Grating Spectrometer. This spectrometer utilizes slumped glass Wolter-1 optics, an array of gratings, and a CCD camera. We discuss the unique capabilities of this design, the expected performance, the science return, and the perceived impact to future missions.

Big Data and Data Science: Opportunities and Challenges of iSchools

Directory of Open Access Journals (Sweden)

Il-Yeol Song

2017-08-01

Full Text Available Due to the recent explosion of big data, our society has been rapidly going through digital transformation and entering a new world with numerous eye-opening developments. These new trends impact the society and future jobs, and thus student careers. At the heart of this digital transformation is data science, the discipline that makes sense of big data. With many rapidly emerging digital challenges ahead of us, this article discusses perspectives on iSchools’ opportunities and suggestions in data science education. We argue that iSchools should empower their students with “information computing” disciplines, which we define as the ability to solve problems and create values, information, and knowledge using tools in application domains. As specific approaches to enforcing information computing disciplines in data science education, we suggest the three foci of user-based, tool-based, and application-based. These three foci will serve to differentiate the data science education of iSchools from that of computer science or business schools. We present a layered Data Science Education Framework (DSEF with building blocks that include the three pillars of data science (people, technology, and data, computational thinking, data-driven paradigms, and data science lifecycles. Data science courses built on the top of this framework should thus be executed with user-based, tool-based, and application-based approaches. This framework will help our students think about data science problems from the big picture perspective and foster appropriate problem-solving skills in conjunction with broad perspectives of data science lifecycles. We hope the DSEF discussed in this article will help fellow iSchools in their design of new data science curricula.

Rapid enzymatic analysis of plasma for tyrosine.

Science.gov (United States)

Shimizu, H; Taniguchi, K; Sugiyama, M; Kanno, T

1990-01-01

In this rapid, simple, and convenient enzymatic method for measurement of tyrosine in plasma, tyrosine is converted to tyramine by action of tyrosine decarboxylase (EC 4.1.1.25) and the tyramine produced is oxidized to p-hydroxybenzyl aldehyde and hydrogen peroxide by action of tyramine oxidase (EC 1.4.3.9). The hydrogen peroxide is reacted with 4-aminoantipyrine and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine in the presence of peroxidase (EC 1.11.1.7) to obtain quinoneimine dye, the absorbance of which is measured at 570 nm. Thus tyrosine is measured in the visible range. The CV was 4.6% or less, and the measurement was unaffected by other amino acids, except for phenylalanine. The values obtained (y) correlated well with those obtained with an amino acid analyzer (x): y = 0.902x + 3.92 mumol/L (Syx = 12.3; r = 0.985; n = 54).

Implementation science approaches for integrating eHealth research into practice and policy.

Science.gov (United States)

Glasgow, Russell E; Phillips, Siobhan M; Sanchez, Michael A

2014-07-01

To summarize key issues in the eHealth field from an implementation science perspective and to highlight illustrative processes, examples and key directions to help more rapidly integrate research, policy and practice. We present background on implementation science models and emerging principles; discuss implications for eHealth research; provide examples of practical designs, measures and exemplar studies that address key implementation science issues; and make recommendations for ways to more rapidly develop and test eHealth interventions as well as future research, policy and practice. The pace of eHealth research has generally not kept up with technological advances, and many of our designs, methods and funding mechanisms are incapable of providing the types of rapid and relevant information needed. Although there has been substantial eHealth research conducted with positive short-term results, several key implementation and dissemination issues such as representativeness, cost, unintended consequences, impact on health inequities, and sustainability have not been addressed or reported. Examples of studies in several of these areas are summarized to demonstrate this is possible. eHealth research that is intended to translate into policy and practice should be more contextual, report more on setting factors, employ more responsive and pragmatic designs and report results more transparently on issues important to potential adopting patients, clinicians and organizational decision makers. We outline an alternative development and assessment model, summarize implementation science findings that can help focus attention, and call for different types of more rapid and relevant research and funding mechanisms. Published by Elsevier Ireland Ltd.

The MIRAX x-ray astronomy transient mission

Science.gov (United States)

Braga, João; Mejía, Jorge

2006-06-01

The Monitor e Imageador de Raios-X (MIRAX) is a small (~250 kg) X-ray astronomy satellite mission designed to monitor the central Galactic plane for transient phenomena. With a field-of-view of ~1000 square degrees and an angular resolution of ~6 arcmin, MIRAX will provide an unprecedented discovery-space coverage to study X-ray variability in detail, from fast X-ray novae to long-term (~several months) variable phenomena. Chiefly among MIRAX science objectives is its capability of providing simultaneous complete temporal coverage of the evolution of a large number of accreting black holes, including a detailed characterization of the spectral state transitions in these systems. MIRAX's instruments will include a soft X-ray (2-18 keV) and two hard X-ray (10-200 keV) coded-aperture imagers, with sensitivities of ~5 and ~2.6 mCrab/day, respectively. The hard X-ray imagers will be built at the Instituto Nacional de Pesquisas Espaciais (INPE), Brazil, in close collaboration with the Center for Astrophysics & Space Sciences (CASS) of the University of California, San Diego (UCSD) and the Institut fur Astronomie und Astrophysik of the University of Tubingen (IAAT) in Germany; UCSD will provide the crossed-strip position-sensitive (0.5- mm spatial resolution) CdZnTe (CZT) hard X-ray detectors. The soft X-ray camera, provided by the Space Research Organization Netherlands (SRON), will be the spare flight unit of the Wide Field Cameras that flew on the Italian-Dutch satellite BeppoSAX. MIRAX is an approved mission of the Brazilian Space Agency (Agnecia Espacial Brasileira - AEB) and is scheduled to be launched in 2011 in a low-altitude (~550 km) circular equatorial orbit. In this paper we present recent developments in the mission planning and design, as well as Monte Carlo simulations performed on the GEANT-based package MGGPOD environment (Weidenspointner et al. 2004) and new algorithms for image digital processing. Simulated images of the central Galactic plane as it

Design of the Information Science and Systems (IS Curriculum in a Computer and Information Sciences Department