Ultra-short-period WC/SiC multilayer coatings for x-ray applications

Recently, the GaSb/InAs superlattice system has received renewed attention. The interest stems from a model demonstrating that short period Ga1-xInxSb/InAs superlattices will have both a band gap less than 100 meV and high optical absorption coefficients, principal requirements for infrared detector applications. Because this superlattice system contains two species of cations and anions, it is possible to prepare either InSb-like or GaAs-like interfaces. As such, the system presents a unique opportunity to examine interfacial properties.We used molecular beam epitaxy (MBE) to prepare an extensive set of GaSb/InAs superlattices grown on an GaSb buffer, which, in turn had been grown on a (100) GaAs substrate. Through appropriate shutter sequences, the interfaces were directed to assume either an InSb-like or GaAs-like character. These superlattices were then studied with a variety of ex-situ probes such as x-ray diffraction and Raman spectroscopy. These probes confirmed that, indeed, predominantly InSb-like and GaAs-like interfaces had been achieved.

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Estimation of Wear Resistance for Multilayer Coatings Obtained by Nitrogenchroming

Metals ◽

10.3390/met11081153 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1153

Author(s):

Ivan Pavlenko ◽

Jozef Zajac ◽

Nadiia Kharchenko ◽

Ján Duplák ◽

Vitalii Ivanov ◽

...

Keyword(s):

Wear Resistance ◽

Spectral Analysis ◽

Friction Coefficient ◽

Cutting Tools ◽

Wear Intensity ◽

Maximum Amount ◽

Multilayer Coatings ◽

Wear Depth ◽

X Ray ◽

Machine Parts

This article deals with improving the wear resistance of multilayer coatings as a fundamental problem in metal surface treatment, strengthening elements of cutting tools, and ensuring the reliability of machine parts. It aims to evaluate the wear depth for multilayer coatings by the mass loss distribution in layers. The article’s primary purpose is to develop a mathematical method for assessing the value of wear for multilayer steel-based coatings. The study material is a multilayer coating applied to steel DIN C80W1. The research was performed using up-to-date laboratory equipment. Nitrogenchroming has been realized under overpressure in two successive stages: nitriding for 36 h at temperature 540 °C and chromizing during 4 h at temperature 1050 °C. The complex analysis included several options: X-ray phase analysis, local micro-X-ray spectral analysis, durometric analysis, and determination of wear resistance. These analyses showed that after nitrogenchroming, the three-layer protective coating from Cr23C6, Cr7C3, and Cr2N was formed on the steel surface. Spectral analysis indicated that the maximum amount of chromium 92.2% is in the first layer from Cr23C6. The maximum amount of carbon 8.9% characterizes the layer from Cr7C3. Nitrogen is concentrated mainly in the Cr2N layer, and its maximum amount is 9.4%. Additionally, it was determined that the minimum wear is typical for steel DIN C80W1 after nitrogenchroming. The weight loss of steel samples by 25 mg was obtained. This value differs by 3.6% from the results evaluated analytically using the developed mathematical model of wear of multilayer coatings after complex metallization of steel DIN C80W1. As a result, the impact of the loading mode on the wear intensity of steel was established. As the loading time increases, the friction coefficient of the coated samples decreases. Among the studied samples, plates from steel DIN C80W1 have the lowest friction coefficient after nitrogenchroming. Additionally, a linear dependence of the mass losses on the wearing time was obtained for carbide and nitride coatings. Finally, an increase in loading time leads to an increase in the wear intensity of steels after nitrogenchroming. The achieved scientific results are applicable in developing methods of chemical-thermal treatment, improving the wear resistance of multilayer coatings, and strengthening highly loaded machine parts and cutting tools.

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Development of R.F. Sputtered Cu / Si Multilayer Coatings for X-Ray Mirror Applications

Journal of Optics ◽

10.1007/bf03549347 ◽

1999 ◽

Vol 28 (1) ◽

pp. 1-13

Author(s):

D. Bhattacharyya ◽

N. C. Das ◽

A. P. Roy ◽

R. Chitra ◽

S. Basu

Keyword(s):

Multilayer Coatings ◽

X Ray

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Properties of Faint X-ray Activity of XTE J1908+094 in 2019

Galaxies ◽

10.3390/galaxies9020025 ◽

2021 ◽

Vol 9 (2) ◽

pp. 25

Author(s):

Debjit Chatterjee ◽

Arghajit Jana ◽

Kaushik Chatterjee ◽

Riya Bhowmick ◽

Sujoy Kumar Nath ◽

...

Keyword(s):

Black Hole ◽

Temporal Analysis ◽

Power Density Spectrum ◽

Periodic Oscillations ◽

Telescope Array ◽

Density Spectrum ◽

X Ray ◽

Black Hole Candidate ◽

Short Period ◽

Spectral State

We study the properties of the faint X-ray activity of Galactic transient black hole candidate XTE J1908+094 during its 2019 outburst. Here, we report the results of detailed spectral and temporal analysis during this outburst using observations from Nuclear Spectroscopic Telescope Array (NuSTAR). We have not observed any quasi-periodic-oscillations (QPOs) in the power density spectrum (PDS). The spectral study suggests that the source remained in the softer (more precisely, in the soft–intermediate) spectral state during this short period of X-ray activity. We notice a faint but broad Fe Kα emission line at around 6.5 keV. We also estimate the probable mass of the black hole to be 6.5−0.7+0.5M⊙, with 90% confidence.

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Progress In Extreme Ultraviolet And Soft X-Ray Multilayer Coatings

10.1117/12.932997 ◽

1982 ◽

Author(s):

Arno K. Hagenlocher

Keyword(s):

Extreme Ultraviolet ◽

Multilayer Coatings ◽

X Ray

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Combined HREELS, Raman and X-ray diffraction study of short-period GaAsAlAs superlattices

Surface Science ◽

10.1016/s0039-6028(96)01048-5 ◽

1996 ◽

Vol 368 (1-3) ◽

pp. 185-189 ◽

Cited By ~ 3

Author(s):

T Tsuruoka ◽

Y Uehara ◽

S Ushioda ◽

T Kojima ◽

Y Sugiyama

Keyword(s):

Diffraction Study ◽

X Ray Diffraction ◽

X Ray ◽

Short Period

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Magnetic assessment and modelling of the Aramis undulator beamline

Journal of Synchrotron Radiation ◽

10.1107/s1600577518002205 ◽

2018 ◽

Vol 25 (3) ◽

pp. 686-705 ◽

Cited By ~ 3

Author(s):

M. Calvi ◽

C. Camenzuli ◽

R. Ganter ◽

N. Sammut ◽

Th. Schmidt

Keyword(s):

Magnetic Properties ◽

Magnetic Measurement ◽

Hall Probe ◽

Measurement Equipment ◽

Series Production ◽

Close Collaboration ◽

X Ray ◽

Short Period ◽

Reduction Methods ◽

Paul Scherrer

Within the SwissFEL project at the Paul Scherrer Institute (PSI), the hard X-ray line (Aramis) has been equipped with short-period in-vacuum undulators, known as the U15 series. The undulator design has been developed within the institute itself, while the prototyping and the series production have been implemented through a close collaboration with a Swiss industrial partner, Max Daetwyler AG, and several subcontractors. The magnetic measurement system has been built at PSI, together with all the data analysis tools. The Hall probe has been designed for PSI by the Swiss company SENIS. In this paper the general concepts of both the mechanical and the magnetic properties of the U15 series of undulators are presented. A description of the magnetic measurement equipment is given and the results of the magnetic measurement campaign are reported. Lastly, the data reduction methods and the associated models are presented and their actual implementation in the control system is detailed.

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Lifetime Stability and Microstructure Properties of Cr/B4C X-ray Reflective Multilayer Coatings

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2019.16480 ◽

2019 ◽

Vol 19 (1) ◽

pp. 554-561 ◽

Cited By ~ 1

Author(s):

Catherine Burcklen ◽

Regina Soufli ◽

Jennifer Rebellato ◽

Christopher Walton ◽

Evgueni Meltchakov ◽

...

Keyword(s):

Multilayer Coatings ◽

X Ray

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X-ray image based pneumonia classification using convolutional neural networks

ACCENTS Transactions on Image Processing and Computer Vision ◽

10.19101/tipcv.2020.618050 ◽

2020 ◽

Vol 6 (20) ◽

pp. 54-67

Author(s):

Sarah Badr AlSumairi ◽

Mohamed Maher Ben Ismail

Keyword(s):

Neural Networks ◽

Convolutional Neural Networks ◽

Network Architecture ◽

Data Augmentation ◽

Critical Factor ◽

Classification Problem ◽

X Rays ◽

X Ray ◽

Erroneous Decision ◽

Short Period

Pneumonia is an infectious disease of the lungs. About one third to one half of pneumonia cases are caused by bacteria. Early diagnosis is a critical factor for a successful treatment process. Typically, the disease can be diagnosed by a radiologist using chest X-ray images. In fact, chest X-rays are currently the best available method for diagnosing pneumonia. However, the recognition of pneumonia symptoms is a challenging task that relies on the availability of expert radiologists. Such “human” diagnosis can be inaccurate and subjective due to lack of clarity and erroneous decision. Moreover, the error can increase more if the physician is requested to analyze tens of X-rays within a short period of time. Therefore, Computer-Aided Diagnosis (CAD) systems were introduced to support and assist physicians and make their efforts more productive. In this paper, we investigate, design, implement and assess customized Convolutional Neural Networks to overcome the image-based Pneumonia classification problem. Namely, ResNet-50 and DenseNet-161 models were inherited to design customized deep network architecture and improve the overall pneumonia classification accuracy. Moreover, data augmentation was deployed and associated with standard datasets to assess the proposed models. Besides, standard performance measures were used to validate and evaluate the proposed system.

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