The Effect of Silica Sand Proportion in Laser Scabbling Process on Cement Mortar

Cement mortar composite has a wide range of applications on construction sites, including masonry, plastering and concrete repair. In construction sites, scabbling process is a method to remove from a few millimeters to several centimeters of defect concrete surfaces. As a result, it is essential to investigate the scabbling characteristics for cement mortar with different silica sand proportion in laser scabbling process. In this study, 5 types of cement mortar with different silica sand proportions in mixing were fabricated and scabbled by using a high-density power laser beam. The effects of silica sand proportion in color changing and penetration depth of the samples after laser scabbling process were studied. Furthermore, the generation of micro-cracks and pores were observed by using scanning electron microscopy (SEM). In addition, chemical composition changes between processed zone and non-processed zone were also evaluated by Energy Dispersive X-ray (EDX) analysis. The results of this study are expected to provide valuable knowledge in understanding of the laser scabbling process for cement-based materials.

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Problems in Thin-Film X-ray Quantification

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135897 ◽

1990 ◽

Vol 48 (2) ◽

pp. 458-459

Author(s):

J N Chapman ◽

W A P Nicholson

Keyword(s):

Thin Film ◽

Specimen Thickness ◽

X Rays ◽

Characteristic Peak ◽

Local Composition ◽

X Ray ◽

Measured Ratio ◽

Path Lengths ◽

Composition Changes

Energy dispersive x-ray microanalysis (EDX) is widely used for the quantitative determination of local composition in thin film specimens. Extraction of quantitative data is usually accomplished by relating the ratio of the number of atoms of two species A and B in the volume excited by the electron beam (nA/nB) to the corresponding ratio of detected characteristic photons (NA/NB) through the use of a k-factor. This leads to an expression of the form nA/nB = kAB NA/NB where kAB is a measure of the relative efficiency with which x-rays are generated and detected from the two species.Errors in thin film x-ray quantification can arise from uncertainties in both NA/NB and kAB. In addition to the inevitable statistical errors, particularly severe problems arise in accurately determining the former if (i) mass loss occurs during spectrum acquisition so that the composition changes as irradiation proceeds, (ii) the characteristic peak from one of the minority components of interest is overlapped by the much larger peak from a majority component, (iii) the measured ratio varies significantly with specimen thickness as a result of electron channeling, or (iv) varying absorption corrections are required due to photons generated at different points having to traverse different path lengths through specimens of irregular and unknown topography on their way to the detector.

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Counterfeit Parts Recognition and Detection for Failure Analysts

ISTFA 2010: Conference Proceedings from the 36th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2010p0364 ◽

2010 ◽

Author(s):

Katherine V. Whittington

Keyword(s):

Thermal Cycle ◽

Visual Inspection ◽

Acoustic Microscopy ◽

Scanning Acoustic Microscopy ◽

3D Measurement ◽

X Ray ◽

Wide Range ◽

Electronic Parts ◽

Testing Awareness

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.

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Preparation of Synthetic Zeolites from Coal Fly Ash by Hydrothermal Synthesis

Materials ◽

10.3390/ma14051267 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1267

Author(s):

David Längauer ◽

Vladimír Čablík ◽

Slavomír Hredzák ◽

Anton Zubrik ◽

Marek Matik ◽

...

Keyword(s):

Fly Ash ◽

Coal Combustion ◽

Power Plants ◽

Coal Fly Ash ◽

Thermal Power ◽

Product Analysis ◽

Coal Combustion Products ◽

X Ray ◽

Wide Range ◽

Silica Alumina

Large amounts of coal combustion products (as solid products of thermal power plants) with different chemical and physical properties cause serious environmental problems. Even though coal fly ash is a coal combustion product, it has a wide range of applications (e.g., in construction, metallurgy, chemical production, reclamation etc.). One of its potential uses is in zeolitization to obtain a higher added value of the product. The aim of this paper is to produce a material with sufficient textural properties used, for example, for environmental purposes (an adsorbent) and/or storage material. In practice, the coal fly ash (No. 1 and No. 2) from Czech power plants was firstly characterized in detail (X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX), particle size measurement, and textural analysis), and then it was hydrothermally treated to synthetize zeolites. Different concentrations of NaOH, LiCl, Al2O3, and aqueous glass; different temperature effects (90–120 °C); and different process lengths (6–48 h) were studied. Furthermore, most of the experiments were supplemented with a crystallization phase that was run for 16 h at 50 °C. After qualitative product analysis (SEM-EDX, XRD, and textural analytics), quantitative XRD evaluation with an internal standard was used for zeolitization process evaluation. Sodalite (SOD), phillipsite (PHI), chabazite (CHA), faujasite-Na (FAU-Na), and faujasite-Ca (FAU-Ca) were obtained as the zeolite phases. The content of these zeolite phases ranged from 2.09 to 43.79%. The best conditions for the zeolite phase formation were as follows: 4 M NaOH, 4 mL 10% LiCl, liquid/solid ratio of 30:1, silica/alumina ratio change from 2:1 to 1:1, temperature of 120 °C, process time of 24 h, and a crystallization phase for 16 h at 50 °C.

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Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽

10.3390/ma14071786 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1786

Author(s):

Carla Queirós ◽

Chen Sun ◽

Ana M. G. Silva ◽

Baltazar de Castro ◽

Juan Cabanillas-Gonzalez ◽

...

Keyword(s):

Water Content ◽

Coordination Polymers ◽

Metal Ion ◽

Low Cost ◽

Microwave Assisted Synthesis ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Ft Ir ◽

Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

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Synthesis and Advanced Characterization of Polymer-Protein Core-Shell Nanoparticles

Catalysts ◽

10.3390/catal11060730 ◽

2021 ◽

Vol 11 (6) ◽

pp. 730

Author(s):

Erik Sarnello ◽

Tao Li

Keyword(s):

Particle Size ◽

Small Angle ◽

Core Shell ◽

Assembly Process ◽

Shell Nanoparticles ◽

X Ray ◽

X Ray Scattering ◽

Wide Range ◽

Core Shell Nanoparticles ◽

Ray Scattering

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.

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AGN1 vs AGN2 dichotomy as seen from the point of view of ionized outflows

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320002677 ◽

2019 ◽

Vol 15 (S356) ◽

pp. 96-96

Author(s):

Eleonora Sani

Keyword(s):

Accretion Rate ◽

Point Of View ◽

Emission Lines ◽

Black Hole Mass ◽

X Ray ◽

Bolometric Luminosity ◽

Wide Range ◽

Strong Contrast

AbstractI present a detailed study of ionized outflows in a large sample of 650 hard X-ray detected AGN. Taking advantage of the legacy value of the BAT AGN Spectroscopic Survey (BASS, DR1), we are able to reveal the faintest wings of the [OIII] emission lines associated with outflows. The sample allows us to derive the incidence of outflows covering a wide range of AGN bolometric luminosity and test how the outflow parameters are related with various AGN power tracers, such as black hole mass, Eddington ratio, luminosity. I’ll show how ionized outflows are more frequently found in type 1.9 and type 1 AGN (50% and 40%) with respect to the low fraction in type 2 AGN (20%). Within such a framework, I’ll demonstrate how type 2 AGN outflows are almost evenly balanced between blue- and red-shifted winds. This, in strong contrast with type 1 and type 1.9 AGN outflows which are almost exclusively blue-shifted. Finally, I’ll prove how the outflow occurrence is driven by the accretion rate, whereas the dependence of outflow properties with respect to the other AGN power tracers happens to be quite mild.

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Towards a methodology for the characterisation of the fabric of wet clays using X-ray scattering

E3S Web of Conferences ◽

10.1051/e3sconf/20199201005 ◽

2019 ◽

Vol 92 ◽

pp. 01005

Author(s):

Georgios Birmpilis ◽

Reza Ahmadi-Naghadeh ◽

Jelke Dijkstra

Keyword(s):

Materials Science ◽

Measurement Techniques ◽

Invasive Technique ◽

Colloidal Systems ◽

Characteristic Distance ◽

X Ray ◽

Hydrophobic Coating ◽

X Ray Scattering ◽

Wide Range ◽

Ray Scattering

X-ray scattering is a promising non-invasive technique to study evolving nano- and micromechanics in clays. This study discusses the experimental considerations and a successful method to enable X-ray scattering to study clay samples at two extreme stages of consolidation. It is shown that the proposed sample environment comprising flat capillaries with a hydrophobic coating can be used for a wide range of voids ratios ranging from a clay suspension to consolidated clay samples, that are cut from larger specimens of reconstituted or natural clay. The initial X-ray scattering results using a laboratory instrument indicate that valuable information on, in principal evolving, clay fabric can be measured. Features such as characteristic distance between structural units and particle orientations are obtained for a slurry and a consolidated sample of kaolinite. Combined with other promising measurement techniques from Materials Science the proposed method will help advance the contemporary understanding on the behaviour of dense colloidal systems of clay, as it does not require detrimental sample preparation

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Improvement of the Detection Sensitivity of Edxrf Trace Element Analysis by Means of Efficient X-Ray Focusing Based on Strongly Curved Hopg Crystals

Advances in X-ray Analysis ◽

10.1154/s0376030800022515 ◽

1995 ◽

Vol 39 ◽

pp. 109-117

Author(s):

Burkhard Beckhoff ◽

Birgit Kanngießer

Keyword(s):

High Intensity ◽

Focal Plane ◽

Bragg Reflection ◽

Pyrolytic Graphite ◽

Trace Element Analysis ◽

Detection Sensitivity ◽

Element Analysis ◽

X Ray ◽

Wide Range ◽

Very High

X-ray focusing based on Bragg reflection at curved crystals allows collection of a large solid angle of incident radiation, monochromatization of this radiation, and condensation of the beam reflected at the crystal into a small spatial cross-section in a pre-selected focal plane. Thus, for the Bragg reflected radiation, one can achieve higher intensities than for the radiation passing directly to the same small area in the focal plane. In that case one can profit considerably from X-ray focusing in an EDXRF arrangement. The 00 2 reflection at Highly Oriented Pyrolytic Graphite (HOPG) crystals offers a very high intensity of the Bragg reflected beam for a wide range of photon energies. Furthermore, curvature radii smaller than 10 mm can be achieved for HOPG crystals ensuring efficient X-ray focusing in EDXRF applications. For the trace analysis of very small amounts of specimen material deposited on small areas of thin-filter backings, HOPG based X-ray focusing may be used to achieve a very high intensity of monochromatic excitation radiation.

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Jet-gas interactions at crucial jet power for feedback

Proceedings of the International Astronomical Union ◽

10.1017/s174392131500229x ◽

2014 ◽

Vol 10 (S313) ◽

pp. 260-265

Author(s):

D. M. Worrall ◽

M. Birkinshaw

Keyword(s):

Gas Flows ◽

Rich Cluster ◽

Power Sources ◽

X Ray ◽

Wide Range ◽

Higher Power ◽

Radiative Power ◽

Gas Interactions ◽

Work Done ◽

Radio Luminosity Function

AbstractMost X-ray studies of radio-mode feedback have concentrated on locally-abundant low-power radio sources in relatively rich cluster environments. But the scaling found between mechanical and radiative power, when combined with the radio luminosity function, means that half of the heating in the local Universe is expected from higher-power sources, which lie within a factor of about three of the FRI/II transition, and these sources encounter a wide range of atmosphere properties. We summarize what is observed at FRI/II transition powers from a complete sample observed with modest Chandra exposure times. We then discuss two systems with deep Chandra data. In one we find that the work done in driving shocks exceeds that in evacuating cavities. This source also displays a remarkable jet-cloud interaction, and revealing hotspot X-ray emission. In the second we find evidence of radio-emitting plasma running along boundaries between gas of different temperature, apparently lubricating the gas flows and inhibiting heat transfer, and itself being heavily structured by the process.

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