In Situ Hydration of Sulfoaluminate Cement Mixtures Monitored by Synchrotron X-Ray Diffraction

2018 ◽  
Vol 930 ◽  
pp. 153-157
Author(s):  
Cleusa M. Rossetto ◽  
Rodrigo Uchida Ichikawa ◽  
Luís Gallego Martinez ◽  
Geraldo L. Carezzato ◽  
Alexandre M.G. Carvalho ◽  
...  
Keyword(s):  
Calcium Ions ◽  
Rietveld Analysis ◽  
Deionized Water ◽  
Monochromatic Radiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcium Sulfoaluminate ◽  
Crystalline Precipitate ◽  
Diffraction Patterns

Mixtures of calcium sulfoaluminate and Portland clinkers with gypsum were hydrated with deionized water. The pastes were introduced in 0.7 mm borosilicate capillary tubes and kept at 40 oC while diffraction patterns were collected every 35 s for approximately 3 hours with a monochromatic radiation of 12 keV at the XRD1 beamline of the Laboratório Nacional de Luz Síncrotron (LNLS) in Campinas, SP - Brazil. The main crystalline phases (C2S, C3S, ettringite, ye’elemite and gypsum) involved in the hydration were quantified by Rietveld analysis. The most noticeable fact was the absence of portlandite as a crystalline precipitate, most likely due to the capture of calcium ions to form ettringite.

In situ coupling of atomic force microscopy and sub-micrometer focused X-ray techniques

2014 ◽  
Vol 1712 ◽  
Author(s):  
Thomas W. Cornelius ◽  
Zhe Ren ◽  
Francesca Mastropietro ◽  
Simon Langlais ◽  
Anton Davydok ◽  
...  
Keyword(s):  
Mechanical Response ◽  
Elemental Distribution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cu Nanowires ◽  
Force Microscopy ◽  
Indentation Tests ◽  
Scanning Force ◽  
Diffraction Patterns

ABSTRACTA scanning force microscope for in situ nanofocused X-ray studies (SFINX) has been developed which can be installed on diffractometers at synchrotron beamlines allowing for the combination with various techniques such as coherent X-ray diffraction and fluorescence. The capabilities of this device are demonstrated on Cu nanowires and on Au islands grown on sapphire (0001). The sample topography, crystallinity, and elemental distribution of the same area are investigated by recording simultaneously an AFM image, a scanning X-ray diffraction map, and a fluorescence map. Additionally, the mechanical response of Au islands is studied by in situ indentation tests employing the AFM-tip and recording 2D X-ray diffraction patterns during mechanical loading.

Development of an in situ synchrotron X-ray total scattering setup under pressurized hydrogen gas

2018 ◽  
Vol 51 (3) ◽  
pp. 796-801 ◽  
Author(s):  
Kouji Sakaki ◽  
Hyunjeong Kim ◽  
Akihiko Machida ◽  
Tetsu Watanuki ◽  
Yoshinori Katayama ◽  
...  
Keyword(s):  
Pair Distribution Function ◽  
Hydrogen Gas ◽  
Ex Situ ◽  
Sample Holder ◽  
Hydrogen Storage Materials ◽  
X Ray Diffraction ◽  
Total Scattering ◽  
X Ray ◽  
Diffraction Patterns

This article describes the development of an in situ gas-loading sample holder for synchrotron X-ray total scattering experiments, particularly for hydrogen storage materials, designed to collect diffraction and pair distribution function (PDF) data under pressurized hydrogen gas. A polyimide capillary with a diameter and thickness of 1.4 and 0.06 mm, respectively, connected with commercially available Swagelok fittings was used as an in situ sample holder. Leakage tests confirmed that this sample holder allows 3 MPa of hydrogen gas pressure and 393 K to be achieved without leakage. Using the developed in situ sample holder, significant background and Bragg peaks from the sample holder were not observed in the X-ray diffraction patterns and their signal-to-noise ratios were sufficiently good. The PDF patterns showed sharp peaks in the r range up to 100 Å. The results of Rietveld and PDF refinements of Ni are consistent with those obtained using a polyimide capillary (1.0 mm diameter and 0.04 mm thickness) that has been used for ex situ experiments. In addition, in situ synchrotron X-ray total scattering experiments under pressurized hydrogen gas up to 1 MPa were successfully demonstrated for LaNi4.6Cu.

scholarly journals A Flow-Through Reaction Cell for Studying Minerals Leaching by In-Situ Synchrotron Powder X-ray Diffraction

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 990
Author(s):  
Fatemeh Nikkhou ◽  
Fang Xia ◽  
Xizhi Yao ◽  
Idowu A. Adegoke ◽  
Qinfen Gu ◽  
...  
Keyword(s):  
Flow Rate ◽  
Pressure Leaching ◽  
X Ray Diffraction ◽  
Reaction Cell ◽  
Time Resolved ◽  
X Ray ◽  
Ore Minerals ◽  
Flow Through ◽  
Diffraction Patterns

A flow-through reaction cell has been developed for studying minerals leaching by in-situ time-resolved powder X-ray diffraction, allowing for a better understanding of the leaching mechanisms and kinetics. The cell has the capability of independent control of temperature (up to 95 °C) and flow rate (>0.5 mL min−1) for atmospheric pressure leaching. It was successfully tested at the powder diffraction beamline at the Australian Synchrotron. Galena powder was leached in a citrate solution under flow-through condition at a flow rate of 0.5 mL min−1, while diffraction patterns were collected during the entire leaching process, showing rapid galena dissolution without the formation of secondary mineral phases. The flow-through cell can be used to study leaching processes of other ore minerals.

scholarly journals In-situhigh-pressure powder X-ray diffraction study of α-zirconium phosphate

2014 ◽  
Vol 70 (3) ◽  
pp. 510-516
Author(s):  
Jennifer E. Readman ◽  
Alistair Lennie ◽  
Joseph A. Hriljac
Keyword(s):  
High Pressure ◽  
Synchrotron Radiation ◽  
Zirconium Phosphate ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
Additional Water ◽  
Diffraction Patterns ◽  
Layered Phosphate

The high-pressure structural chemistry of α-zirconium phosphate, α-Zr(HPO4)2·H2O, was studied usingin-situhigh-pressure diffraction and synchrotron radiation. The layered phosphate was studied under both hydrostatic and non-hydrostatic conditions and Rietveld refinement carried out on the resulting diffraction patterns. It was found that under hydrostatic conditions no uptake of additional water molecules from the pressure-transmitting medium occurred, contrary to what had previously been observed with some zeolite materials and a layered titanium phosphate. Under hydrostatic conditions the sample remained crystalline up to 10 GPa, but under non-hydrostatic conditions the sample amorphized between 7.3 and 9.5 GPa. The calculated bulk modulus,K0= 15.2 GPa, showed the material to be very compressible with the weak linkages in the structure of the type Zr—O—P.

X-ray powder diffraction analysis of the heteropoly-molybdate (MoO2)0.5PMo14O42

2003 ◽  
Vol 18 (3) ◽  
pp. 236-239 ◽  
Author(s):  
L. Marosi ◽  
J. Cifré ◽  
C. Otero Areán
Keyword(s):  
Catalytic Activity ◽  
Diffraction Analysis ◽  
Computer Modeling ◽  
Powder Diffraction ◽  
Rietveld Analysis ◽  
Nitrogen Atmosphere ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns

The new heteropoly blue compound (MoO2)0.5PMo14O42, which is relevant in the context of catalytic activity of heteropoly-molybdates, was prepared by controlled thermolysis of (NH4)3PMo12O40 at 730 K in a nitrogen atmosphere. Powder X-ray diffraction analysis showed that this compound has a cubic unit cell, space group Pn3m (No. 224), with ao=11.795(2) Å, Z=2 and DXR=4.2466 g cm−3. Computer modeling and Rietveld analysis of powder diffraction patterns led to a proposed structure of the corresponding Keggin-cage unit PMo14O42.

Statistical measures of spottiness in diffraction rings

2013 ◽  
Vol 47 (1) ◽  
pp. 166-172 ◽  
Author(s):  
Bridget Ingham
Keyword(s):  
Carbon Dioxide ◽  
Size Distribution ◽  
Intensity Variation ◽  
Incident Beam ◽  
Mean Square ◽  
X Ray Diffraction ◽  
X Ray ◽  
Statistical Measures ◽  
Diffraction Patterns

Spotty diffraction rings arise when the size distribution of crystallites illuminated by the incident beam includes crystallites that are large compared with the size of the beam. In this article, several statistical measures are used in conjunction to quantify spottiness and relate it to a crystallite size distribution: the number of peaks, the normalized root mean square intensity variation and the fractal dimension. These are demonstrated by way of example using synchrotron X-ray diffraction patterns collected duringin situcorrosion of mild steel in carbon dioxide-saturated aqueous brine.

In Situ X-Ray Diffraction Study of Thermal Stability of Cu and Cu-Zr Samples Processed by ECAP

2013 ◽  
Vol 753 ◽  
pp. 279-284 ◽  
Author(s):  
Radomír Kužel ◽  
Zdeněk Matěj ◽  
Miloš Janeček
Keyword(s):  
In Situ Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Abnormal Growth ◽  
Angular Pressing ◽  
Dislocation Densities ◽  
Diffraction Patterns ◽  
Number Of Passes ◽  
Thermal Stability Of

X-ray diffraction (XRD) studies of ECAP (equal-channel angular pressing) materials were performed after annealing and by in-situ measurements in XRD high-temperature chamber for samples prepared by different number of passes and number of revolutions, respectively. Main attention was given to Cu and Cu-Zr samples. Significant dependence on number of passes was found for ECAP samples. In-situ measurements were focused not only on temperature dependence but also on time evolution of the diffraction line profiles. Evaluation in terms of dislocation densities, correlation and crystallite size and its distribution was performed by our own software MSTRUCT developed for total powder diffraction pattern fitting. Abnormal growth of some grains with annealing is well-known for copper and leads to the creation of bimodal microstructure. Therefore a special care must be given to the evaluation and a model of two Cu components (larger and smaller crystallites) was fitted to the data if an indication of some crystallite growth appears either in the XRD line profile shape or in two-dimensional diffraction patterns.

scholarly journals Anomalous reflexions in X-ray patterns

1941 ◽  
Vol 179 (976) ◽  
pp. 1-7 ◽  
Keyword(s):  
Simple Theory ◽  
Monochromatic Radiation ◽  
X Ray Diffraction ◽  
Satisfactory Explanation ◽  
Characteristic Radiation ◽  
X Ray ◽  
Diffraction Patterns ◽  
Ray Patterns

The presence on X-ray diffraction patterns of anomalous reflexions, that is to say, reflexions which cannot be accounted for by the simple theory of diffraction, is almost a commonplace. Many of these effects are no doubt to be ascribed to imperfections in the specimen, strains, etc., but even after these have been taken into account there remain streaks and spots for which there is no satisfactory explanation. The observation of effects of the type considered here is by no means novel; Friedrich (1913) recorded them as radial streaks running through the Laue spots in a photograph of KCl. The extra spots are generally very weak compared with the normal Laue reflexions and indeed may not be observed at all unless the photographs are somewhat over-exposed. They are most easily observed on Laue photographs taken with a tube emitting a characteristic radiation such as the K radiation of Cu or Ag, and their study will be greatly facilitated by the use of powerful sources of monochromatic radiation.

scholarly journals Designing a synchrotron micro-focusing beamline for macromolecular crystallography

2016 ◽  
Vol 62 (3) ◽  
pp. 395-400
Author(s):  
Paweł Grochulski ◽  
Mirosław Cygler ◽  
Brian Yates
Keyword(s):  
Room Temperature ◽  
Photon Counting ◽  
Low Noise ◽  
Macromolecular Crystallography ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photon Counting Detector ◽  
Diffraction Patterns ◽  
Ultra Low Noise

After a successful 10 years of operation, the Canadian Macromolecular Crystallography Facility 08ID-1 beamline will undergo an upgrade to establish micro-beam capability. This paper is mostly focussed on optics and computer simulations for ray tracing of the beamline. After completion, the focussed beam at the sample will have a much smaller size of 50 × 5 μm2 (H x V), allowing measurement of X-ray diffraction patterns from much smaller crystals than possible presently. The beamline will be equipped with a fast sample changer and an ultra-low noise photon counting detector, allowing shutter-less operation of the beamline. Additionally, it will be possible to perform in-situ room-temperature experiments.

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