High-Quality 3-D MicroCT Imaging of Source Rocks – Novel Methodology to Measure and Correct for X-Ray Scatter

Abstract Grating-based x-ray phase-contrast imaging has the potential to enhance image quality and provide inner structure details non-destructively. In this work, using grating-based x-ray phase-contrast imaging system and employing integrating-bucket method, the quantitative expressions of signal-to-noise ratios due to photon statistics and mechanical error are analyzed in detail. Photon statistical noise and mechanical error are the main sources affecting the image noise in x-ray grating interferometry. Integrating-bucket method is a new phase extraction method translated to x-ray grating interferometry; hence, its image quality analysis would be of great importance to get high-quality phase image. The authors’ conclusions provide an alternate method to get high-quality refraction signal using grating interferometer, and hence increases applicability of grating interferometry in preclinical and clinical usage.

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Technology of high quality protein crystals’ obtaining aboard the ISS at execution of joint Japanese–Russian experiments

Space engineering and technology ◽

10.33950/spacetech-2308-7625-2020-2-5-25 ◽

2020 ◽

pp. 5-25

Author(s):

Koji INAKA ◽

Saori ICHIMIZU ◽

Izumi YOSHIZAKI ◽

Kiyohito KIHIRA ◽

Elena G. LAVRENKO ◽

...

Keyword(s):

Drug Design ◽

International Space Station ◽

Space Station ◽

Protein Crystals ◽

Diffusion Method ◽

X Ray Diffraction ◽

High Quality ◽

International Space ◽

X Ray ◽

High Quality Protein

A series of space experiments aboard the International Space Station (ISS) associated with high-quality Protein Crystal Growth (PCG) in microgravity conditions can be considered as a unique and one of the best examples of fruitful collaboration between Japanese and Russian scientists and engineers in space, which includes also other ISS International Partners. X-ray diffraction is still the most powerful tool to determine the protein three dimensional structure necessary for Structure based drug design (SBDD). The major purpose of the experiment is to grow high quality protein crystals in microgravity for X-ray diffraction on Earth. Within one and a half decade, Japan and Russia have established an efficient process over PCG in space to support latest developments over drug design and structural biology. One of the keys for success of the experiment lies in how precisely pre-launch preparations are made. Japanese party provides flight equipment for crystallization and ensures the required environment to support the experiment aboard of the ISS’s Kibo module, and also mainly takes part of the experiment ground support such as protein sample characterization, purification, crystallization screening, and solution optimization for microgravity experiment. Russian party is responsible for integration of the flight items equipped with proteins and precipitants on board Russian transportation space vehicles (Soyuz or Progress), for delivery them at the ISS, transfer to Kibo module, and returning the experiments’ results back on Earth aboard Soyuz manned capsule. Due to close cooperation of the parties and solid organizational structure, samples can be launched at the ISS every half a year if the ground preparation goes smoothly. The samples are crystallized using counter diffusion method at 20 degree C for 1–2.5 months. After samples return, the crystals are carefully taken out from the capillary, and frozen for X-ray diffraction at SPring8 facility in Japan. Extensive support of researchers from both countries is also a part of this process. The paper analyses details of the PCG experiment scheme, unique and reliable technology of its execution, and contains examples of the application. Key words: International Space Station, Protein crystals, Microgravity, International collaboration.

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Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽

10.3390/s21134554 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4554

Author(s):

Ralph-Alexandru Erdelyi ◽

Virgil-Florin Duma ◽

Cosmin Sinescu ◽

George Mihai Dobre ◽

Adrian Bradu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Radiation Dose ◽

Imaging Techniques ◽

Image Resolution ◽

Optical Coherence ◽

X Rays ◽

High Quality ◽

X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

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Non-destructive handheld XRF study of archaeological composite silver objects—the case study of the late Roman Seuso Treasure

Archaeological and Anthropological Sciences ◽

10.1007/s12520-021-01321-4 ◽

2021 ◽

Vol 13 (5) ◽

Author(s):

Viktória Mozgai ◽

Bernadett Bajnóczi ◽

Zoltán May ◽

Zsolt Mráv

Keyword(s):

Fluorescence Analysis ◽

The Body ◽

High Quality ◽

X Ray ◽

Composite Objects ◽

Mechanical Attachment ◽

Non Destructive ◽

Made In ◽

Late Roman

AbstractThis study details the non-destructive chemical analysis of composite silver objects (ewers, situlas, amphora and casket) from one of the most significant late Roman finds, the Seuso Treasure. The Seuso Treasure consists of fourteen large silver vessels that were made in the fourth–early fifth centuries AD and used for dining during festive banquets and for washing and beautification. The measurements were systematically performed along a pre-designed grid at several points using handheld X-ray fluorescence analysis. The results demonstrate that all the objects were made from high-quality silver (above 90 wt% Ag), with the exception of the base of the Geometric Ewer B. Copper was added intentionally to improve the mechanical properties of soft silver. The gold and lead content of the objects shows constant values (less than 1 wt% Au and Pb). The chemical composition as well as the Bi/Pb ratio suggests that the parts of the composite objects were manufactured from different silver ingots. The ewers were constructed in two ways: (i) the base and the body were made separately, or (ii) the ewer was raised from a single silver sheet. The composite objects were assembled using three methods: (i) mechanical attachment; (ii) low-temperature, lead-tin soft solders; or (iii) high-temperature, copper-silver hard solders. Additionally, two types of gilding were revealed by the XRF analysis, one with remnants of mercury, i.e. fire-gilding, and another type without remnants of mercury, presumably diffusion bonding.

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Crystallographic features of ammonium fluoroelpasolites: dynamic orientational disorder in crystals of (NH4)3HfF7 and (NH4)3Ti(O2)F5

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520616017534 ◽

2017 ◽

Vol 73 (1) ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Anatoly A. Udovenko ◽

Alexander A. Karabtsov ◽

Natalia M. Laptash

Keyword(s):

Single Crystal ◽

Electron Density ◽

Diffraction Data ◽

Central Atom ◽

X Ray Diffraction ◽

Dynamic Nature ◽

Orientational Disorder ◽

High Quality ◽

Structural Units ◽

X Ray

A classical elpasolite-type structure is considered with respect to dynamically disordered ammonium fluoro-(oxofluoro-)metallates. Single-crystal X-ray diffraction data from high quality (NH4)3HfF7 and (NH4)3Ti(O2)F5 samples enabled the refinement of the ligand and cationic positions in the cubic Fm \bar 3 m (Z = 4) structure. Electron-density atomic profiles show that the ligand atoms are distributed in a mixed (split) position instead of 24e. One of the ammonium groups is disordered near 8c so that its central atom (N1) forms a tetrahedron with vertexes in 32f. However, a center of another group (N2) remains in the 4b site, whereas its H atoms (H2) occupy the 96k positions instead of 24e and, together with the H3 atom in the 32f position, they form eight spatial orientations of the ammonium group. It is a common feature of all ammonium fluoroelpasolites with orientational disorder of structural units of a dynamic nature.

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Short-pulse laser-driven x-ray radiography

High Power Laser Science and Engineering ◽

10.1017/hpl.2016.31 ◽

2016 ◽

Vol 4 ◽

Cited By ~ 12

Author(s):

E. Brambrink ◽

S. Baton ◽

M. Koenig ◽

R. Yurchak ◽

N. Bidaut ◽

...

Keyword(s):

Pulse Laser ◽

Short Pulse ◽

Incident Angle ◽

Laboratory Astrophysics ◽

Signal To Noise ◽

High Quality ◽

X Ray ◽

Short Pulse Laser ◽

Short Pulse Lasers

We have developed a new radiography setup with a short-pulse laser-driven x-ray source. Using a radiography axis perpendicular to both long- and short-pulse lasers allowed optimizing the incident angle of the short-pulse laser on the x-ray source target. The setup has been tested with various x-ray source target materials and different laser wavelengths. Signal to noise ratios are presented as well as achieved spatial resolutions. The high quality of our technique is illustrated on a plasma flow radiograph obtained during a laboratory astrophysics experiment on POLARs.

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Low Temperature Illitization through Illite-Dioctahedral Vermiculite Mixed Layers in a Tropical Saline Lake Rich in Hydrothermal Fluids (Sochagota Lake, Colombia)

Minerals ◽

10.3390/min11050523 ◽

2021 ◽

Vol 11 (5) ◽

pp. 523

Author(s):

Gabriel Ricardo Cifuentes ◽

Juan Jiménez-Millán ◽

Claudia Patricia Quevedo ◽

Fernando Nieto ◽

Javier Cuadros ◽

...

Keyword(s):

Electron Microscopy ◽

Organic Matter ◽

Low Temperature ◽

High Salinity ◽

Source Rocks ◽

Temperate Climate ◽

Lake Basin ◽

X Ray ◽

Saline Waters ◽

Mixed Layers

In this investigation, we showed that high salinity promoted by hydrothermal inputs, reducing conditions of sediments with high content in organic matter, and the occurrence of an appropriate clay mineral precursor provide a suitable framework for low-temperature illitization processes. We studied the sedimentary illitization process that occurs in carbonaceous sediments from a lake with saline waters (Sochagota Lake, Colombia) located at a tropical latitude. Water isotopic composition suggests that high salinity was produced by hydrothermal contribution. Materials accumulated in the Sochagota Lake’s southern entrance are organic matter-poor sediments that contain detrital kaolinite and quartz. On the other hand, materials formed at the central segment and near the lake exit (north portion) are enriched in organic matter and characterized by the crystallization of Fe-sulfides. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), and energy dispersive X-ray spectrometry (EDX) data allowed for the identification of illite and illite-dioctahedral vermiculite mixed layers (I-DV), which are absent in the southern sediments. High humidity and temperate climate caused the formation of small-sized metastable intermediates of I-DV particles by the weathering of the source rocks in the Sochagota Lake Basin. These particles were deposited in the low-energy lake environments (middle and north part). The interaction of these sediments enriched in organic matter with the saline waters of the lake enriched in hydrothermal K caused a reducing environment that favored Fe mobilization processes and its incorporation to I-DV mixed layers that acted as mineral precursor for fast low temperature illitization, revealing that in geothermal areas clays in lakes favor a hydrothermal K uptake.

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X-Ray Microanalysis of Art Glass Surfaces

Microscopy Today ◽

10.1017/s1551929510000891 ◽

2010 ◽

Vol 18 (5) ◽

pp. 28-31

Author(s):

R.B. Simmons

Keyword(s):

Heavy Metals ◽

Low Cost ◽

Metallic Surfaces ◽

High Quality ◽

X Ray ◽

Skin Contact ◽

Work Area ◽

The World ◽

Glass Surfaces ◽

Glass Workers

In recent years there has been a virtual explosion in the world of art glass. New glass formulations have brought a host of new colors into the marketplace, and the availability of low-cost, high-quality torches and other tools has brought art glass to the hobbyist. In addition to burn risks and possible cutting injury, there are a number of less obvious hazards that should be known to novice glass workers. One of these is the presence of heavy metals in or on glass surfaces and possibly in the atmosphere immediately surrounding the work area, presenting both potential skin contact and inhalation hazards. This study examines the metallic surfaces generated on five glass colors commonly used in art glass jewelry.

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High Quality GaAs Mis Diodes With Very Low Surface State Density

MRS Proceedings ◽

10.1557/proc-209-703 ◽

1990 ◽

Vol 209 ◽

Author(s):

Yoshihisa Fujisaki ◽

Sumiko Sakai ◽

Saburo Ataka ◽

Kenji Shibata

Keyword(s):

Chemical Vapor Deposition ◽

Density Of States ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

State Density ◽

High Quality ◽

Metal Insulator ◽

X Ray ◽

Mis Devices

ABSTRACTHigh quality GaAs/SiO2 MIS( Metal Insulator Semiconductor ) diodes were fabricated using (NH4)2S treatment and photo-assisted CVD( Chemical Vapor Deposition ). The density of states at the GaAs and SiO2 interface is the order of 1011 cm-2eV-1 throughout the forbidden energy range, which is smaller by the order of two than that of the MIS devices made by the conventional CVD process. The mechanism attributable to the interface improvement was investigated through XPS( X-ray Photoelectron Spectroscopy ) analyses.

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Deep Learning Enabled Deblurring of Computed Tomography Images of Porous Media

10.2118/208665-ms ◽

2021 ◽

Author(s):

Khalid Labib Alsamadony ◽

Ertugrul Umut Yildirim ◽

Guenther Glatz ◽

Umair bin Waheed ◽

Sherif M. Hanafy

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Transfer Learning ◽

Temporal Resolution ◽

Exposure Time ◽

Ct Images ◽

Loss Functions ◽

High Quality ◽

X Ray ◽

Training Images

Abstract Computed tomography (CT) is an important tool to characterize rock samples allowing quantification of physical properties in 3D and 4D. The accuracy of a property delineated from CT data is strongly correlated with the CT image quality. In general, high-quality, lower noise CT Images mandate greater exposure times. With increasing exposure time, however, more wear is put on the X-Ray tube and longer cooldown periods are required, inevitably limiting the temporal resolution of the particular phenomena under investigation. In this work, we propose a deep convolutional neural network (DCNN) based approach to improve the quality of images collected during reduced exposure time scans. First, we convolve long exposure time images from medical CT scanner with a blur kernel to mimic the degradation caused because of reduced exposure time scanning. Subsequently, utilizing the high- and low-quality scan stacks, we train a DCNN. The trained network enables us to restore any low-quality scan for which high-quality reference is not available. Furthermore, we investigate several factors affecting the DCNN performance such as the number of training images, transfer learning strategies, and loss functions. The results indicate that the number of training images is an important factor since the predictive capability of the DCNN improves as the number of training images increases. We illustrate, however, that the requirement for a large training dataset can be reduced by exploiting transfer learning. In addition, training the DCNN on mean squared error (MSE) as a loss function outperforms both mean absolute error (MAE) and Peak signal-to-noise ratio (PSNR) loss functions with respect to image quality metrics. The presented approach enables the prediction of high-quality images from low exposure CT images. Consequently, this allows for continued scanning without the need for X-Ray tube to cool down, thereby maximizing the temporal resolution. This is of particular value for any core flood experiment seeking to capture the underlying dynamics.

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