Dolomite Stimulation with Retarded Acids

2021 ◽  
Author(s):  
Christopher Daeffler ◽  
Julia Fernandez del Valle ◽  
Jean Elkhoury ◽  
Mohan Panga ◽  
Max Nikolaev ◽  
...  
Keyword(s):  
Single Phase ◽  
Oil And Gas ◽  
Core Flow ◽  
X Ray ◽  
Flow Experiment ◽  
X Ray Computed ◽  
The Difference ◽  
Indiana Limestone ◽  
Flow Experiments ◽  
Treatment Design

Abstract Globally, dolomite formations are important reservoirs for oil and gas. Acid stimulation is commonly used to extend the life of carbonate reservoirs, and a good understanding of the fluid performance is essential for effective treatment design. Three acids, hydrochloric acid (HCl), emulsified HCl, and a single-phase retarded acid based on HCl, were assessed for their ability to create wormholes in Silurian dolomite under laboratory conditions using a standard core flow experiment. Select cores were imaged by X-ray computed tomography to visualize the wormhole morphology. Similar experiments in Indiana limestone was used as a control. The core flow experiments showed that the pore volume to break-through (PVbt) values for the retarded acids in Indiana limestone were less sensitive to changes in temperature overall than unmodified HCl. For Silurian dolomite though, the opposite is observed. HCl has uniformly high PVbt values at lower (200 °F) and higher (325 °F). The emulsified acid and the single-phase retarded acid are more efficient than HCl, but the difference is smaller at 325 °F. Core images revealed that all three fluids had some degree of wormhole branching at 200 °F and much less branching at 325 °F. By visual inspection, the single-phase retarded acid has less ramification than HCl and the emulsified acid. Overall, the results show that retarded acids should make effective stimulation fluids for dolomite reservoirs.

Oxygen content, microstructure, and superconductivity of YBa2Cu3O7−x

1987 ◽  
Vol 2 (6) ◽  
pp. 743-749 ◽  
Author(s):  
M. P. A. Viegers ◽  
D. M. de Leeuw ◽  
C. A. H. A. Mutsaers ◽  
H. A. M. van Hal ◽  
H. C. A. Smoorenburg ◽  
...  
Keyword(s):  
Single Phase ◽  
Inner Core ◽  
X Ray ◽  
Cell Parameters ◽  
Preparation Conditions ◽  
Transmission Electron ◽  
Quench Temperature ◽  
Orthorhombic Cell ◽  
The Difference ◽  
Individual Grains

The influence of preparation conditions and microstructure on the superconductive properties of single-phase poly-crystalline YBa2Cu3O7−x was investigated by electron probe microanalysis, transmission electron microscopy (TEM), and x-ray powder diffraction as a function of temperature in various ambients supplemented by resistivity and susceptibility measurements. Leaching of Ba was observed when samples were brought in contact with water. The TEM imaging revealed that individual grains have an extremely defect-rich outer shell and an inner core with a domain structure with a and b axes interchanged. The transition temperature Tc was found to decrease with increasing quench temperature in the range 400–900°C. The Tc was observed to be linearly proportional to the difference in the orthorhombic cell parameters (b-a). Further implications are discussed.

scholarly journals Technical Note. The Concept of a Computer System for Interpretation of Tight Rocks Using X-Ray Computed Tomography Results

2017 ◽  
Vol 39 (1) ◽  
pp. 101-107 ◽  
Author(s):  
Magdalena Habrat ◽  
Paulina Krakowska ◽  
Edyta Puskarczyk ◽  
Mariusz Jędrychowski ◽  
Paweł Madejski
Keyword(s):  
Computed Tomography ◽  
Computer System ◽  
Oil And Gas ◽  
Technical Note ◽  
Quantitative Interpretation ◽  
X Ray ◽  
Qualitative And Quantitative ◽  
Rock Structure ◽  
X Ray Computed ◽  
Tight Rocks

Abstract The article presents the concept of a computer system for interpreting unconventional oil and gas deposits with the use of X-ray computed tomography results. The functional principles of the solution proposed are presented in the article. The main goal is to design a product which is a complex and useful tool in a form of a specialist computer software for qualitative and quantitative interpretation of images obtained from X-ray computed tomography. It is devoted to the issues of prospecting and identification of unconventional hydrocarbon deposits. The article focuses on the idea of X-ray computed tomography use as a basis for the analysis of tight rocks, considering especially functional principles of the system, which will be developed by the authors. The functional principles include the issues of graphical visualization of rock structure, qualitative and quantitative interpretation of model for visualizing rock samples, interpretation and a description of the parameters within realizing the module of quantitative interpretation.

THE XRD STUDY OF THE EFFECT OF SLIGHT CHANGE IN STRUCTURE ON THE SUPERCONDUCTIVITY OF Y-Ba-Cu-O SYSTEM MATERIAL

1987 ◽  
Vol 01 (07n08) ◽  
pp. 289-293 ◽  
Author(s):  
WANG HUAQIN ◽  
ZHANG SHIYUAN ◽  
JIN TONGZHENG ◽  
HAN SHIYING ◽  
QIU DIRONG ◽  
...  
Keyword(s):  
Single Phase ◽  
Crystal Symmetry ◽  
Epr Spectra ◽  
Processing Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrd Study ◽  
The Difference ◽  
Diffraction Patterns ◽  
Flowing Oxygen

In this paper the differences in diffraction intensities from some crystal planes in the X-ray diffraction patterns of high Tc Y-Ba-Cu-O system superconductors prepared by different processing conditions and the difference among various structure cells in references are interpreted using computer fitting. The results suggest that there exists two structure cells in the single phase YBa2Cu3O7−x samples. Both structure cells have the same crystal symmetry and almost the same lattice parameters, a=3.821Å, b=3.892Å and c=11.676Å, but the different distortion degree of Cu2-O plane. According to EPR spectra measured on the same samples, it is considered that the improvement of superconductivity for the samples prepared by two-step annealing in flowing oxygen may be related to concentration of the structure cell with more serious distortion on the Cu2-O plane.

Evaluation of Volumetric Data for Dimensional X-Ray Computed Tomography

2017 ◽  
Vol 870 ◽  
pp. 223-227
Author(s):  
Hiroyuki Fujimoto ◽  
Makoto Abe ◽  
Kazuya Matsuzaki ◽  
Osamu Sato ◽  
Toshiyuki Takatsuji
Keyword(s):  
Computed Tomography ◽  
Computer Simulation ◽  
Volumetric Data ◽  
X Ray ◽  
Measurement Capability ◽  
Geometric Objects ◽  
X Ray Computed ◽  
The Difference

The measurement capability of the dimensional X-ray Computed Tomography (DXCT) is studied by a computer simulation and the result was compared to the observed data obtained by the measurement of calibrated gauges of same shape that consist of simple geometric forms. The simulation showed that the measurement using polychromatic x-ray is different from that of monochromatic x-ray, but the difference was far smaller than expected from the results of observed data. These results indicated that the deviation of the measured values of geometric objects was not caused by simple origin and more causes have to be taken into consideration for the actual apparatus.

scholarly journals Minimization of Dose Load in Algorithms of X-Ray Computed Tomography

2019 ◽  
Vol 64 (4) ◽  
pp. 282
Author(s):  
L. A. Bulavin ◽  
Yu. F. Zabashta ◽  
O. V. Motolyha
Keyword(s):  
Computed Tomography ◽  
Experimental Error ◽  
Minimum Condition ◽  
Regularization Methods ◽  
Dose Load ◽  
X Ray ◽  
Minimum Dose ◽  
Inverse Projection ◽  
X Ray Computed ◽  
The Difference

An algorithm has been developed for the reconstruction of an X-ray image obtained at the minimum dose load on the researched object and provided a given image accuracy. This algorithm combines approaches typical of the inverse projection and regularization methods. The image is formed by overlaying filtered projections, and the filtering parameters are determined from the minimum condition for the difference between the discrepancy and the experimental error.

Critical Current Properties of Hg(Re)1223 Single Crystals with Various Oxygen Content

2001 ◽  
Vol 689 ◽  
Author(s):  
S. Ueda ◽  
J. Shimoyama ◽  
T. Sato ◽  
S. Horii ◽  
K. Otzschi ◽  
...  
Keyword(s):  
Single Crystals ◽  
Critical Current ◽  
Single Phase ◽  
Magnetic Hysteresis ◽  
Maximum Size ◽  
Peak Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Difference ◽  
Second Peak

ABSTRACTHigh quality single crystals of Hg(Re)1223 were grown by the flux method using BaZrO3 crucible, which is stable against molten Ba-Cu-O. The maximum size of the obtained crystal was 1 × 1.1 × 0.1mm3 in dimension. X-ray diffraction analysis revealed that grown crystals are of Hg(Re)1223 single phase with c0 = 15.7 å. In the magnetic hysteresis curves for post-annealed Hg(Re)1223 single crystals under H // c, large second peak effect was found with steep increase of magnetization at approximately 2∼3kOe independent of temperature. The peak field systematically increased with a decrease of temperature, suggesting generation of field-induced pinning. Critical current density and irreversibility field of single crystals were dependent on synthesis batch, possibly due to the difference in resulting concentration of Re, while postannealing under various conditions did not affect largely for critical current properties. Irreversibility lines of the Hg(Re)1223 single crystals locate at higher fields than that of Re-free Hg1223. This suggests that electromagnetic anisotropy is reduced by Re-doping, which is consistent with the recent results on the resistive anisotropy in the normal state.

Ferroelectricity in SrTiO3 Ceramics Induced by Pr Doping

2004 ◽  
Vol 848 ◽  
Author(s):  
A. Durán ◽  
E. Martínez ◽  
J. Mata ◽  
J. Heiras ◽  
X. Solans ◽  
...  
Keyword(s):  
Single Phase ◽  
Temperature Differential ◽  
X Ray Diffraction ◽  
Ionic Radii ◽  
Ferroelectric State ◽  
X Ray ◽  
The Difference ◽  
Diffraction Patterns ◽  
A Site ◽  
Srtio3 Ceramics

ABSTRACTFerroelectricity was induced in SrTiO3 by the Sr exchange for Pr ion in the A site of the perovskite ABO3-type structure. X-ray diffraction patterns show single phase crystalline structure in the SrxPr1-xTiO3 compound for x=0, 0.025, 0.050, 0.075 and 0.1 compositions. Rietveld refinement shows that the unit cell volume decreases with the increasing of Pr content as a consequence of the difference between Sr/Pr ionic radii. Furthermore, high-temperature differential thermoanalysis (DTA) displays a small anomaly at about 118 °C which is probably due to the Pr ion producing a distortion of the perovskite structure via an off-center site. This deformation in the lattice induces a measurable polar behavior of the solid solution. Dielectric permittivity (ε vs T) measurements display a well defined peak at about 238 °C. Furthermore, a well defined hysteresis loop at 30 °C with a remnant polarization that tends to decrease with increasing Pr concentration is observed. Both experimental results confirm the ferroelectric state induced by the Pr ion.

Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane

1982 ◽  
Vol 40 ◽  
pp. 74-75
Author(s):  
Jules S. Jaffe ◽  
Robert M. Glaeser
Keyword(s):  
Purple Membrane ◽  
Data Set ◽  
High Resolution Data ◽  
X Ray ◽  
X Ray Crystallography ◽  
Fourier Techniques ◽  
Versus Protein ◽  
The Difference ◽  
Difference Fourier ◽  
Ideal Method

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.

Antiphase Boundaries in Ordered Ni3FE Crystals

1969 ◽  
Vol 27 ◽  
pp. 62-63
Author(s):  
Y. H. Liu
Keyword(s):  
Domain Size ◽  
Antiphase Domain ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardening Mechanism ◽  
Superlattice Structure ◽  
Disordered Phase ◽  
Domain Boundaries ◽  
Atomic Scattering ◽  
The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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