First Results of the DITO-Experiment at the HARWI II Beamline at GKSS/DESY

At the HARWI II beamline at the GKSS outstation at DESY a new experiment for position sensitive diffractometry and tomography called DITO was built and commissioned this year. Due to the available high energy synchrotron radiation with photon energies up to 100 keV it is possible to investigate the bulk of metallic samples of a few mm thickness with both methods. The diffractometry detector allows the investigation of the phase composition as well as phase sensitive determination of residual stresses with a spatial resolution of 6 μm while the tomography detector can either measure a whole tomogram in high resolution mode with a spatial resolution of 2 μm within 3 to 4 hours or in high speed mode recording a whole tomogram within 15 seconds with a spatial resolution of 40 μm.

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Phase composition depth profiles using spatially resolved energy dispersive X-ray diffraction

Journal of Applied Crystallography ◽

10.1107/s0021889804024148 ◽

2004 ◽

Vol 37 (6) ◽

pp. 967-976 ◽

Cited By ~ 9

Author(s):

Andrew C. Jupe ◽

Stuart R. Stock ◽

Peter L. Lee ◽

Nikhila N. Naik ◽

Kimberly E. Kurtis ◽

...

Keyword(s):

Phase Composition ◽

Spatial Resolution ◽

Zinc Coating ◽

High Energy ◽

Sulfate Attack ◽

Energy Dispersive ◽

X Ray Diffraction ◽

X Ray ◽

Spatially Resolved ◽

Composition Profiles

Spatially resolved energy dispersive X-ray diffraction, using high-energy synchrotron radiation (∼35–80 keV), was used nondestructively to obtain phase composition profiles along the radii of cylindrical cement paste samples to characterize the progress of the chemical changes associated with sulfate attack on the cement. Phase distributions were acquired to depths of ∼4 mm below the specimen surface with sufficient spatial resolution to discern features less than 200 µm thick. The experimental and data analysis methods employed to obtain quantitative composition profiles are described. The spatial resolution that could be achieved is illustrated using data obtained from copper cylinders with a thin zinc coating. The measurements demonstrate that this approach is useful for nondestructively visualizing the sometimes complex transformations that take place during sulfate attack on cement-based materials. These transformations can be spatially related to microstructure as seen by computed microtomography.

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Evaluation and comparison of a CdTe based photon counting detector with an energy integrating detector for X-ray phase sensitive imaging of breast cancer

Journal of X-Ray Science and Technology ◽

10.3233/xst-211028 ◽

2021 ◽

pp. 1-13

Author(s):

Muhammad U. Ghani ◽

Farid H. Omoumi ◽

Xizeng Wu ◽

Laurie L. Fajardo ◽

Bin Zheng ◽

...

Keyword(s):

Breast Cancer ◽

Spatial Resolution ◽

Standard Dose ◽

Photon Counting ◽

High Energy ◽

Edge Enhancement ◽

X Ray ◽

Photon Counting Detector ◽

Phase Sensitive ◽

Observer Studies

PURPOSE: To compare imaging performance of a cadmium telluride (CdTe) based photon counting detector (PCD) with a CMOS based energy integrating detector (EID) for potential phase sensitive imaging of breast cancer. METHODS: A high energy inline phase sensitive imaging prototype consisting of a microfocus X-ray source with geometric magnification of 2 was employed. The pixel pitch of the PCD was 55μm, while 50μm for EID. The spatial resolution was quantitatively and qualitatively assessed through modulation transfer function (MTF) and bar pattern images. The edge enhancement visibility was assessed by measuring edge enhancement index (EEI) using the acrylic edge acquired images. A contrast detail (CD) phantom was utilized to compare detectability of simulated tumors, while an American College of Radiology (ACR) accredited phantom for mammography was used to compare detection of simulated calcification clusters. A custom-built phantom was employed to compare detection of fibrous structures. The PCD images were acquired at equal, and 30% less mean glandular dose (MGD) levels as of EID images. Observer studies along with contrast to noise ratio (CNR) and signal to noise ratio (SNR) analyses were performed for comparison of two detection systems. RESULTS: MTF curves and bar pattern images revealed an improvement of about 40% in the cutoff resolution with the PCD. The excellent spatial resolution offered by PCD system complemented superior detection of the diffraction fringes at boundaries of the acrylic edge and resulted in an EEI value of 3.64 as compared to 1.44 produced with EID image. At MGD levels (standard dose), observer studies along with CNR and SNR analyses revealed a substantial improvement of PCD acquired images in detection of simulated tumors, calcification clusters, and fibrous structures. At 30% less MGD, PCD images preserved image quality to yield equivalent (slightly better) detection as compared to the standard dose EID images. CONCLUSION: CdTe-based PCDs are technically feasible to image breast abnormalities (low/high contrast structures) at low radiation dose levels using the high energy inline phase sensitive imaging technique.

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Rapid and sensitive determination of Dns-amino acids in plasma using high-speed octadecyl liquid chromatographic columns

Journal of Chromatography B Biomedical Sciences and Applications ◽

10.1016/0378-4347(87)80210-4 ◽

1987 ◽

Vol 413 ◽

pp. 25-31 ◽

Cited By ~ 6

Author(s):

Jouko T. Työppönen

Keyword(s):

Amino Acids ◽

High Speed ◽

Chromatographic Columns ◽

Sensitive Determination ◽

Liquid Chromatographic

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Design and Development of a Compressed-Air Driven, Counterblow High Energy-Rate Forming Machine

Proceedings of the Institution of Mechanical Engineers ◽

10.1243/pime_proc_1965_180_051_02 ◽

1965 ◽

Vol 180 (1) ◽

pp. 777-789

Author(s):

I. Marland ◽

A. J. Organ ◽

S. A. Tobias

Keyword(s):

High Speed ◽

High Energy ◽

Maximum Energy ◽

Compressed Air ◽

Energy Output ◽

Net Energy ◽

Energy Rate ◽

High Energy Rate ◽

Approach Velocity

As a first stage in the development of a large, double-acting, petrol combustion actuated, high energy-rate forming machine, a compressed-air driven device was designed and constructed. This was intended to be a research vehicle for establishing general design principles, particularly as far as the structural configurations and the method of platen synchronization were concerned. The characteristic design features of this machine are discussed and an appraisal of the design is given. Experiments were carried out with the aim of (1) determining the net energy output of the machine and (2) finding the maximum platen approach velocity for a range of values of the initial charge pressure. For the determination of the energy output of the machine, calibrated crush-gauges were used, the results being cross-checked by measuring the maximum relative velocity between the platens, and from this and the weight of the moving masses finding the maximum kinetic energy. For the determination of the maximum platen approach velocity, electric velocity transducers were used, the results being checked with the aid of a high-speed ciné camera. The maximum energy output of the machine was found to be 75 000 ft lb, which was attained with a maximum impact velocity of 80 ft/s, as aimed at in the design of the machine. Some typical examples of hot forgings produced with the machine are also presented.

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High Spatial Resolution Strain Measurements Within Bulk Materials by Slit-Imaging

MRS Proceedings ◽

10.1557/proc-590-241 ◽

1999 ◽

Vol 590 ◽

Cited By ~ 11

Author(s):

U. Lienert ◽

R. Martins ◽

S. Grigull ◽

M. Pinkerton ◽

H.F. Poulsen ◽

...

Keyword(s):

Spatial Resolution ◽

Residual Strain ◽

High Energy ◽

Gauge Length ◽

Polycrystalline Materials ◽

Reconstruction Technique ◽

Strain Measurements ◽

Large Samples ◽

Position Sensitive ◽

Longitudinal Resolution

ABSTRACTHigh energy synchrotron radiation is employed for residual strain measurements from local gauge volumes within the bulk of polycrystalline materials. The longitudinal spatial resolution is defined by placing a narrow imaging slit behind the sample and recording the intensity distribution on a position sensitive detector. It is shown that the sample to slit distance can be increased without sacrificing longitudinal resolution by applying a reconstruction technique. Hence, space is provided for large samples and sample environments. The reconstruction technique is described and validated by measuring the residual strain profile of a shot-peened Al sample. A longitudinal gauge length of 95 üm is achieved at 52 keV with a sample to slit distance of 10 cm.

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Angle-resolved phase-sensitive determination of the in-plane gap symmetry in YBa2Cu3O7−δ

Nature Physics ◽

10.1038/nphys215 ◽

2006 ◽

Vol 2 (3) ◽

pp. 190-194 ◽

Cited By ~ 100

Author(s):

J. R. Kirtley ◽

C. C. Tsuei ◽

Ariando ◽

C. J. M. Verwijs ◽

S. Harkema ◽

...

Keyword(s):

Gap Symmetry ◽

Sensitive Determination ◽

Phase Sensitive

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DAFS experiments for phase-sensitive determination of local structure around Zr in Co/Zr multilayers

Journal of Synchrotron Radiation ◽

10.1107/s0909049598014150 ◽

1999 ◽

Vol 6 (3) ◽

pp. 329-331 ◽

Cited By ~ 1

Author(s):

D. C. Meyer ◽

A. Kupsch ◽

K. Richter ◽

P. Paufler

Keyword(s):

Local Structure ◽

Sensitive Determination ◽

Phase Sensitive

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First results with the ANET Compact Thermal Neutron Collimator

Journal of Instrumentation ◽

10.1088/1748-0221/16/11/p11025 ◽

2021 ◽

Vol 16 (11) ◽

pp. P11025

Author(s):

O. Sans-Planell ◽

M. Costa ◽

E. Durisi ◽

E. Mafucci ◽

L. Menzio ◽

...

Keyword(s):

Spatial Resolution ◽

Potential Application ◽

Neutron Imaging ◽

Field Of View ◽

Medium Size ◽

Neutron Sources ◽

First Results ◽

Limited Length ◽

Measuring Campaign

Abstract This paper presents the first determination of the spatial resolution of the ANET Compact Neutron Collimator, obtained with a measuring campaign at the LENA Mark-II TRIGA reactor in Pavia. This novel collimator consists of a sequence of collimating and absorbing channels organised in a chessboard-like geometry. It has a scalable structure both in length and in the field of view. It is characterized by an elevated collimation power within a limited length. Its scalability and compactness are added values with respect to traditional collimating system. The prototype tested in this article is composed of 4 concatenated stages, each 100 mm long, with a channel width of 2.5 mm, delivering a nominal L/D factor of 160. This measuring campaign illustrates the use of the ANET collimator and its potential application in neutron imaging for facilities with small or medium size neutron sources.

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White Beam Microdiffraction Experiments for the Determination of the Local Plastic Behaviour of Polycrystals

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.103 ◽

2006 ◽

Vol 524-525 ◽

pp. 103-108 ◽

Cited By ~ 3

Author(s):

Olivier Castelnau ◽

Philippe Goudeau ◽

G. Geandier ◽

Nobumichi Tamura ◽

Jean Luc Béchade ◽

...

Keyword(s):

Spatial Resolution ◽

Elastic Strain ◽

Mean Field ◽

Polycrystalline Materials ◽

Plastic Behavior ◽

Full Field ◽

White Beam ◽

First Results ◽

Individual Grains

The overall plastic behavior of polycrystalline materials strongly depends on the microstructure and on the local rheology of individual grains. The characterization of the strain and stress heterogeneities within the specimen, which result from the intergranular mechanical interactions, is of particular interest since they largely control the microstructure evolutions such as texture development, work-hardening, damage, recrystallization, etc. The influence of microstructure on the effective behavior can be addressed by physical-based predictive models (homogenization schemes) based either on full-field or on mean-field approaches. But these models require the knowledge of the grain behavior, which in turn must be determined on the real specimen under investigation. The microextensometry technique allows the determination of the surface total (i.e. plastic + elastic) strain field with a micrometric spatial resolution. On the other hand, the white beam X-ray microdiffraction technique developed recently at the Advanced Light Source enables the determination of the elastic strain with the same spatial resolution. For polycrystalline materials with grain size of about 10 micrometers, a complete intragranular mechanical characterization can thus be performed by coupling these two techniques. The very first results obtained on plastically deformed copper and zirconium specimens are presented.

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