Quản lý giếng bơm ép nước bằng phương pháp điện trở điện dung và đồ thị Hall

Khi tiến hành bơm ép nước duy trì áp suất mỏ, việc giám sát và đánh giá quá trình bơm ép nước nhằm nâng cao hiệu quả thu hồi dầu đóng vai trò quan trọng. Sự suy giảm độ tiếp nhận của giếng bơm ép nước gây ra các vấn đề phức tạp, ảnh hưởng không tốt tới các thiết bị trên bề mặt cũng như thiết bị trong lòng giếng. Ngoài ra việc bơm ép không đúng lưu lượng gây ra hiện tượng ngập nước sớm tại các giếng khai thác ảnh hưởng đến thu hồi dầu. Bài báo giới thiệu chương trình quản lý giếng bơm ép nước bằng phương pháp điện trở điện dung và đồ thị Hall (Hall plot) nhằm hạn chế tối thiểu các vấn đề phức tạp này.

Optical X-Ray Diffraction Data Analysis Using the Williamson–Hall Plot Method in Estimation of Lattice Strain-Stress

Lattice stress and strain was analysed with estimated crystalline size of the synthesised ZnFe2O4 nanoparticles from x-ray diffraction data using Williamson-Hall (W-H) method. This very peculiar method was used to analyse the other physical parameters such as strain, stress, and energy density. Values calculated from the W-H method include uniform deformation model, uniform deformation stress model, and uniform deformation energy density model. These are very useful methods to label each data point on the Williamson-Hall plot according to the index of its reflection. Particularly, the root mean square value of strain was calculated from the interplanar distance using these three models. The three models have given different strain values by reason of the anisotropic nature of the nanopartcles. The average grain size of ZnFe2O4 nanoparticles estimated from FESEM image, Scherrer's formula, and W-H analysis is relatively correlated.

Structural, Optical, Ferroelectric and Magnetic Properties of NiTiO3 Ceramic Synthesized by Citrate Gel Method

The NiTiO3 ceramic was synthesized in nanostructured form by citrate gel method. The phase structure, microstructure and magnetic properties of synthesized compounds were investigated by X-ray diffraction (XRD), scanning electron microscope and vibrating sample magnetometer. Williamson–Hall plot was used to calculate the crystallite size and microstrain of sample. The XRD analysis showed the formation of rhombohedral crystal structure of synthesized powders. The crystallite size is about 35[Formula: see text]nm and microstrain is [Formula: see text]. The optical band gap was estimated from UV-Visible spectrum with value of 2.43[Formula: see text]eV. The NiTiO3 samples showed coexistence of ferroelectric and antiferromagnetic properties at room temperature.

In Vitro Corrosion and Tribocorrosion Performance of Biocompatible Carbide Coatings

The present study aims to explain the corrosion and the tribocorrosion performance in simulated conditions of the human body by the level of stress, adhesion of coating to substrate, roughness, and hardness. The coatings were synthesized by the cathodic arc evaporation method on 316L stainless steel substrates to be used for load bearing implants. Structure, elemental, and phase compositions were studied by means of energy dispersive spectrometry and X-ray diffraction, respectively. The grain size and strain of the coatings were determined by the Williamson–Hall plot method. Tests on hardness, adhesion, roughness, and electrochemical behavior in 0.9% NaCl solution at 37 ± 0.5 °C were carried out. Tribocorrosion performances, evaluated by measuring the friction coefficient and wear rate, were conducted in 0.9% NaCl solution using the pin on disc method at 37 ± 0.5 °C. TiC and ZrC exhibited a (111) preferred orientation, while TiNbC had a (200) orientation and the smallest crystallite size (8.1 nm). TiC was rougher than ZrC and TiNbC; the lowest roughness was found for TiNbC coatings. The highest hardness and adhesion values were found for TiNbC, followed by TiC and the ZrC. All coatings improved the corrosion resistance of 316L steels, but TiNbC showed the best corrosion behavior. TiNbC had the lowest friction coefficient (1.6) and wear rate (0.99 × 10−5 mm3·N−1∙m−1) values, indicating the best tribocorrosive performance in 0.9% NaCl at 37 ± 0.5 °C.

Structural Change and Magnetic Properties of Mechanically Alloyed Spinel Ferrite CoFe2O4

Magnetic property studies and the crystallite structures evolution of spinel ferrite CoFe2O4 particles are reported in this paper. The ferrite was prepared through mechanical milling of all alloy precursors and sintered at various temperatures of 800, 900, 1000, and 1100 °C to promote the crystalline structure. X-ray diffraction (XRD) and Williamson-Hall plot were used to calculate the mean crystallite size and microstrain. Changes in the microstructure and crystallite sizes were occurring due to sintering treatments. It is found that the remanence (Mr) and saturation magnetization (Ms) increase with increasing sintering temperature, but a decrease occurred only at the temperature of 1100 °C. The optimum magnetic properties were obtained in a sample sintered at 1000 °C with a value of Mr = 36.00 emu/g and Ms= 74.05 emu/g.

Optical X-Ray Diffraction Data Analysis Using the Williamson–Hall Plot Method in Estimation of Lattice Strain-Stress

Lattice stress and strain was analysed with estimated crystalline size of the synthesised ZnFe2O4 nanoparticles from x-ray diffraction data using Williamson-Hall (W-H) method. This very peculiar method was used to analyse the other physical parameters such as strain, stress, and energy density. Values calculated from the W-H method include uniform deformation model, uniform deformation stress model, and uniform deformation energy density model. These are very useful methods to label each data point on the Williamson-Hall plot according to the index of its reflection. Particularly, the root mean square value of strain was calculated from the interplanar distance using these three models. The three models have given different strain values by reason of the anisotropic nature of the nanopartcles. The average grain size of ZnFe2O4 nanoparticles estimated from FESEM image, Scherrer's formula, and W-H analysis is relatively correlated.

A New Explanation for the Effect of Dynamic Strain Aging on Negative Strain Rate Sensitivity in Fe–30Mn–9Al–1C Steel

In this study, the evolution of the mechanical properties of Fe–30Mn–9Al–1C steel has been determined in tensile tests at strain rates of 10−4 to 102 s−1. The results show that the strain rate sensitivity becomes a negative value when the strain rate exceeds 100 s−1 and this abnormal evolution is attributed to the occurrence of dynamic strain aging. Due to the presence of intergranular κ-carbides, the fracture modes of steel include ductile fracture and intergranular fracture. The values of dislocation arrangement parameter M were obtained using a modified Williamson–Hall plot. It has been found that once the strain rate sensitivity becomes negative, the interaction of dislocations in the steel is weakened and the free movement of dislocation is enhanced. Adiabatic heating promotes the dynamic recovery of steel at a high strain rate.

Synthesis and Characterization of Co0.8-x Nix Zn0.2 Fe2O4 Ferrites by Williamson–Hall and Size–Strain Plot Methods

The Co-Zn ferrite (x=0.00) and Nickel doped Co-Zn ferrites (x=0.24) was synthesized by low cost solid state reaction method and characterized by XRD technique. The X-ray diffraction results for the samples showed the formation of single phase cubic spinel. The lattice constant and particle size for Co-Zn ferrite(x=0.00) is found to be 8.3465 Å and 26.72 nm and for Nickel doped (x=0.24) it is 8.3440 Å and 24.21nm. Micro strain (ε), Dislocation density(ρD), Hopping lengths (LA and LB), Bond lengths (A - O and B-O), Ionic radii (rA and rB), Texture coefficients (Thkl) and Standard deviation (σ) are also reported. The particle size is confirmed by scanning electron microscope (SEM). The Williamson-Hall plot and stress-strain plot also employed to understand the mechanical properties of materials.