Reflection X-ray Diffraction Research Articles

Research on Diagenetic Evolution and Hydrocarbon Accumulation Periods of Chang 8 Reservoir in Zhenjing Area of Ordos Basin

The Mesozoic Chang 8 Section in the Zhenjing area is a typical low permeability-tight sand reservoir and is regarded as the most important set of paybeds in the study area. Guided by the principles of basic geological theory, the diagenetic evolution process and hydrocarbon accumulation periods of the Chang 8 reservoir in the study area were determined through various techniques. More specifically, core observation, scanning electron microscopy (SEM), X-ray diffraction (XRD), and vitrinite reflectance experiments were performed in combination with systematic studies on rock pyrolysis and the thermal evolutionary history of basins, the illite-dating method, and so on. The Chang 8 reservoir is dominated by feldspar lithic and lithic feldspar sandstones. Quartz, feldspar, and lithic fragments are the major clastic constituents. In clay minerals, the chlorite content is the highest, followed by illite/smectite formation and kaolinite, while the illite content is the lowest. The major diagenesis effect of the Chang 8 reservoir includes compaction, cementation, dissolution, metasomatism, and rupturing. The assumed diagenetic sequence is the following: mechanical composition → early sedimentation of chlorite clay mineral membrane → early cementation of sparry calcite → authigenic kaolinite precipitation → secondary production and amplification of quartz → dissolution of carbonate cement → dissolution of feldspar → late cementation of minerals such as ferrocalcite. Now, the study area is in Stage A in the middle diagenetic period. Through the inclusion of temperature measurements, in conjunction with illite dating and thermal evolutionary history analysis technology in basins, the Chang 8 reservoir of this study was determined as the phase-I continuous accumulation process and the reservoir formation epoch was 105~125 Ma, which was assigned to the Middle Early Cretaceous Epoch.

Synthesis, crystal structure, and photoluminescence of the new nitridoboroaluminosilicate phosphor (Sr0.93Eu0.07)11B2(Al0.275Si0.725)40N59

Single crystals of a new nitride, (Sr0.93Eu0.07)11B2(Al0.275Si0.725)40N59, were synthesized by heating a mixture of binary nitride powders at 2030 ​°C under nitrogen gas at 0.85 ​MPa. The fundamental X-ray diffraction reflections from a single crystal were indexed with the monoclinic cell parameters a ​= ​5.6836(4) Å, b ​= ​46.772(3) Å, c ​= ​5.6845(4) Å, and β = 118.028(2)° and diffuse streaks were observed between the reflections. The crystal structure was analyzed based on a statistical average structural model with space group Cm. The structure was determined to comprise (Al/Si)N4 tetrahedra and BN3 planar triangles forming a three-dimensional framework by sharing nitrogen atoms with Sr/Eu atoms located in the cage portions of the framework. Stacking faults in the b-axis direction and disordered atomic arrangements along the [1 0 1] direction on the a-c plane were observed by scanning transmission electron microscopy. These single crystal grains were found to emit red light when irradiated with near ultraviolet or blue light, with a maximum emission wavelength of 616 ​nm and a full width at half-maximum value of 106 ​nm in response to 450 ​nm light.

Surface erosion in nc-ZrN/a-ZrCu multilayer films after He irradiation

The work is dedicated to the study of the phase stability and surface erosion of a novelZr-based multilayer system consisting of a combination of ceramic (ZrN) and metallic glass (ZrCu) nanoscale layers after He irradiation (40 keV and doses up to 1.1 × 1018 cm−2). Periodic ZrN/Zr1-xCux multilayers with elementary layer thicknesses of 5 nm/5 nm and 5 nm/10 nm and Cu content x = 0.45, 0.53, 0.61 and 0.74 were grown by magnetron sputter-deposition from Zr and Cu targets at the substrate temperature of 300 °C. X-ray diffraction and X-ray reflectivity analysis reveal that multilayered films consist of alternating nanocrystalline (nc) ZrN and amorphous (a) ZrCu layers with relatively sharp interfaces. The stability of the phase composition of nc-ZrN/a-Zr1-xCux multilayer films to irradiation with helium ions up to fluence of 1.1 × 1018 cm−2 has been established. For x = 0.74, crystallization of the metallic glass layer was observed.The surface integrity of the multilayer films remained unaltered up to an ion fluence of 5 × 1017 cm−2. At higher ion fluence, surface erosion of the nc-ZrN/a-Zr1-xCux films occurs by the flacking mechanism. In this case, an increase in the thickness of the amorphous Zr1-xCux layer and in Cu content leads to improved radiation resistance as the critical fluence for delamination increases from 5 × 1017 cm−2 upto 8 × 1017 cm−2.

Photodegradation of Indigosol Blue Dye Using TiO2/Natural Zeolite Photocatalyst

Indigosol blue is one of the dyes that has not been widely studied for photodegradation. This study aims to determine the photodegradation activity of indigosol blue using TiO2/Natural zeolite. TiO2 embedded in natural zeolite was synthesized using the sol-gel method. The synthesis results were characterized using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), and UV-Vis Diffuse Reflectance Spectroscopy (DRS). The characterization of TiO2-zeolite obtained a bandgap energy of 2.62 eV that could be seen in the UV-Vis DRS spectra. UV light is used during the photodegradation process to irradiate TiO2-zeolite photocatalyst. The results show that the optimum mass of natural TiO2-zeolite photocatalyst was 0.02 g with a degradation percentage of 58.3%. The optimum radiation time was 30 min with a degradation percentage of 58.7%, and the optimum concentration of blue indigosol was 600 ppm with a degradation percentage of 58.7%. TiO2/Natural zeolite photocatalyst could degrade indigosol blue dye effectively at the optimum condition.

Microstructure and Intrinsic Strain of Nanocrystals in Ferroelectric (Na,K)NbO3 Nanofibers.

Densely woven highly crystallized biocompatible sodium–potassium niobate Na0.35K0.65NbO3 fibers with an average diameter of 100–200 nm and several hundreds of microns in length were sintered by the sol–gel calcination-assisted electrospinning technique. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (TEM) confirmed preferential cube-on-cube [001] orientation of nanocrystals within the fiber’s body, separated by a low angle grain boundary. The Williamson–Hall method was employed to analyze the broadening of XRD reflections and to accurately determine the size and intrinsic strain of nanocrystal fiber aggregates. The main objective of this article is to test the potential capacity of direct XRD analysis to noninvasively control crystallite size and lattice distortion in core-shell coaxial nanofibers.

Formation of lower bainite in a high carbon steel – an in-situ synchrotron XRD study

The microstructural evolution of and simultaneous dimensional changes in high-carbon SAE 52100 bearing steel were monitored continuously during austempering for 120 min at selected temperatures in the range of 210 °C-270 °C, and also during its subsequent tempering to 340 °C for an additional 120 min, via high-energy X-ray diffraction in real time and in-situ dilatometry. The austenite-to-bainitic ferrite transformation induces lattice defects and internal lattice stresses that increase with austempering time and at lower austempering temperatures. These changes are evidenced by the increase in the full-width half-maximum of the relevant reflections in X-ray diffraction. The lattice parameter of bainitic ferrite takes its highest value during the early stages of austempering, and then gradually decreases as the transformation progresses. This observation points to an initial state of carbon supersaturation in the ferritic lattice that is likely reducing due to carbon segregation close to dislocations, fine carbide precipitation within the bainitic ferrite, and carbon partitioning into the surrounding austenite. The carbon partitioning into austenite is evidenced in particular at the higher austempering temperatures of 240 °C and 270 °C, at which there is a noticeable increase in the lattice parameter of the remaining austenite at longer times. The dimensions of the bearing steel specimens are governed by the volume change due to the formation of bainitic ferrite during austempering and by the relaxation of its lattice distortion during tempering at 340 °C in the absence of further phase transformation.

Investigation of Exchange Bias in Irmn/Nife Bilayer Thin Films Using Magnetoresistance Technique

A bottom pinned Si/SiO2/Ta(20)/IrMn(15)/NiFe(10)/Ta(5) film has been fabricated using an ion beam sputtering system at room temperature. Post-deposition magnetic annealing was performed on sputtered multilayer thin film in a vacuum of 2´10-6 mbar at 250˚C for one hour in an in-plane magnetic field of 1.8 kG. The X-ray diffraction and X-ray reflectivity measurements have been performed for the structural and thickness analysis, respectively. The roughness of individual layers was determined using XRR measurements. The longitudinal MOKE measurements have been performed to measure the exchange bias, coercivity, and magnetic anisotropy at room temperature. The magnetoresistance measurement technique is employed to demonstrate the thermal evaluation of the exchange bias effect, training effect, and magnetization reversal asymmetry at room temperature and low temperature. The magnetoresistance measurement revealed a large exchange bias, pronounced magnetization reversal asymmetry, and enhancement in the training effects at 20 K. The experimental result exhibits the occurrence of temperature-dependent change from uniaxial to biaxial exchange anisotropy.

Disordering of β-Ga2O3 upon irradiation with Si+ ions: Effect of surface orientation

Development of gallium oxide-based devices is one of the most promising areas of modern electronic technology. The method of ion implantation is widely used in electronic engineering; however, it has not yet been sufficiently studied for gallium oxide from a physical point of view. One of the interesting questions is the possible impact of surface orientation of β-Ga2O3 single crystals on the structural damage upon ion irradiation. In this work, the effect of Si+ ion irradiation on the structural properties of β-Ga2O3 crystals with (−201) and (010) surface orientations has been investigated by X-ray diffraction and small-angle reflection electronography. It is established that mechanical stresses in the irradiated layer depend on surface orientation: in the case of (−201) orientation, the stress in lateral to the surface direction is compressive, while it is tensile for the (010) orientation. At one and the same irradiation dose, the degree of damage for (010) orientation is shown to be stronger than that for (−201). Possible explanation is suggested for the surface orientation effect.

Importance of Nuclear Quantum Effects for Molecular Cocrystals with Short Hydrogen Bonds.

Many efforts have been recently devoted to the design and investigation of multicomponent pharmaceutical solids, such as salts and cocrystals. The experimental distinction between these solid forms is often challenging. Here, we show that the transformation of a salt into a cocrystal with a short hydrogen bond does not occur as a sharp phase transition but rather a smooth shift of the positional probability of the hydrogen atoms. A combination of solid-state NMR spectroscopy, X-ray diffraction, and diffuse reflectance measurements with density functional theory calculations that include nuclear quantum effects (NQEs) provides evidence of temperature-induced hydrogen atom shift in cocrystals with short hydrogen bonds. We demonstrate that for the predictions of the salt/cocrystal solid forms with short H-bonds, the computations have to include NQEs (particularly hydrogen nuclei delocalization) and temperature effects.

Synthesize Fe<sub>3</sub>O<sub>4</sub>-TiO<sub>2 </sub>Composite for Methyl Orange Photocatalytic Degradation

The effect of Fe3O4 percentage on Fe3O4-TiO2 composite for methyl orange photocatalytic degradation has been investigated. Hydrothermal was carried out on TiO2 before being combined with Fe3O4 by precipitation method. The composites were characterized by means of Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and UV-Vis diffuse and reflectance spectroscopy (UV-Vis DRS). The photocatalytic activity of Fe3O4-TiO2 composites were evaluated for methyl orange degradation. The addition of Fe3O4 to TiO2 could reduce the bandgap energy. The lowest bandgap energy was obtained at 20% Fe3O4-TiO2 composite. By using this composited, the degradation of methyl orange was 90%.

Characteristics comparison and occurrence mode of different types of soluble organic matter in lacustrine shale in the Dongying Sag, eastern China

Soluble organic matter (SOM) in shale can be divided into free and adsorbed states. However, the characteristics and occurrence mode of different types of SOM remain unclear, which are of great significance to the unconventional oil and gas and hydrocarbon generation mechanism. This paper investigates the characteristics of different types of SOM, discusses the relationships between SOM and minerals, and clarifies the occurrence mode of SOM in shale. Twenty shale samples collected from the Dongying Sag were successively subjected to “organic solvent extraction - alkali hydrolysis - hydrochloric (HCl) acid hydrolysis - hydrochloric/hydrofluoric (HCl/HF) acid hydrolysis” treatments to obtain different types of SOM (extracted SOM, alkali-hydrolyzed SOM, HCl acid-hydrolyzed SOM and HF acid-hydrolyzed SOM), which were then separated into different group components by column chromatography. X-ray diffraction (XRD) and Diffuse reflectance infrared Fourier transform (DRIFT) were used to analyze the original samples and treated residues. Comparison of organic characteristics reveals: (1) Comparison of SOM content shows the order of extracted SOM (about 80%) > HF acid-hydrolyzed SOM (10%) > alkali-hydrolyzed SOM (7%) > HCl acid-hydrolyzed SOM (3%). (2) The extracted SOM is mainly composed of saturates (average content of 65.22%). Resins are the main components of the alkali-hydrolyzed SOM (38.28%) and HCl acid-hydrolyzed SOM (43.69%). For the HF acid-hydrolyzed SOM, the content of asphaltenes is the highest (76.52%). (3) Comparison of SOM polarity shows the order of HF acid-hydrolyzed SOM > alkali-hydrolyzed SOM > HCl acid-hydrolyzed SOM > extracted SOM. Based on the organic characteristics and the relationships between SOM and minerals, there are three occurrence modes of SOM in shale: (1) Free SOM in pores (extracted SOM) is free in the pores and physically adsorbed on pore surfaces. (2) Mineral-bound SOM (alkali-hydrolyzed SOM and HCl acid-hydrolyzed SOM) is chemically adsorbed onto the surfaces of clay minerals and carbonates, and is enclosed in the recrystallized carbonates. (3) SOM in inaccessible kerogen (HF acid-hydrolyzed SOM) is retained by inaccessible kerogen. These findings fully demonstrate the differences in the characteristics of SOM in different occurrence states, which are exemplified by the content, composition, polarity and adsorption. These differences provide a new insight for the study of unconventional oil and gas and hydrocarbon generation mechanism.

The Effect of Oxidation Temperature on the (1000–1300) cm−1 Band in FT-IR Spectra of Silicon Oxide Synthesized by Thermal Oxidation of Silicon Wafers

In this work, silicon wafers were thermal treated in air at temperatures varied in the range 800—1200 °C. The annealed samples were investigated using FTIR, X-ray diffraction, FTIR and optical reflection spectroscopy. The effect of annealing temperature on the (1000–1300) cm−1 band in FT-IR spectra of the prepared samples was investigated. The results showed that thermal oxidation at temperatures less than 1200 °C leads to enhance the phenomenon of the splitting of longitudinal optical and transverse optical stretching motions. This phenomenon was verified by observing the appearance of two overlapping peaks in the region (1000–1300) cm−1 in FT-IR spectra. The results also showed that the splitting process leads to the formation of defects in the crystal structure of silicon, which in turn leads to the formation of silicon nanoparticles.

Study of silicon-to-silicon carbide transformation stages in the process of atomic substitution by the methods of total external X-ray reflection and X-ray diffractometry

X-ray diffraction and total external reflection of X-rays (X-ray reflectometry) methods were used to study the successive stages of synthesis of epitaxial SiC films on Si (100) X-ray diffraction and total external X-ray reflection (XRD) methods were used to study successive stages of synthesis of epitaxial SiC films on Si (100) surfaces, (110) and (111) surfaces by the atom substitution method. The data on the transformation evolution of (100) surfaces were studied, (110) and (111) Si, into SiC surfaces. A comparative analysis of the X-ray structural quality of the SiC layers grown on Si by the atom substitution method with the quality of SiC layers grown by Advanced Epi by the standard CVD method. A modified technique for the total outer X-ray reflection method, based on measurements of the intensity of the reflected X-rays using a special parabolic mirror. It is shown that the method of total external reflection method makes it possible to obtain important information about the degree of surface roughness of SiC layers, the evolution of their crystal structure and plasmon energy in the process of Si to SiC conversion. Keywords: total external reflection, X-ray reflectometry, silicon carbide, plasmons.

Исследование этапов превращения кремния в карбид кремния в процессе атомного замещения методами полного внешнего отражения рентгеновских лучей и рентгеновской дифрактомерии

X-ray diffraction and total external reflection of X-rays (X-ray reflectometry) methods were used to study the successive stages of synthesis of epitaxial SiC films on Si (100) X-ray diffraction and total external X-ray reflection (XRD) methods were used to study successive stages of synthesis of epitaxial SiC films on Si (100) surfaces, (110) and (111) surfaces by the atom substitution method. The data on the transformation evolution of (100) surfaces were studied, (110) and (111) Si, into SiC surfaces. A comparative analysis of the X-ray structural quality of the SiC layers grown on Si by the atom substitution method with the quality of SiC layers grown by Advanced Epi by the standard CVD method. A modified technique for the total outer X-ray reflection method, based on measurements of the intensity of the reflected X-rays using a special parabolic mirror. It is shown that the method of total external reflection method makes it possible to obtain important information about the degree of surface roughness of SiC layers, the evolution of their crystal structure and plasmon energy in the process of Si to SiC conversion.

Study of silicon-to-silicon carbide transformation stages in the process of atomic substitution by the methods of total external X-ray reflection and X-ray diffractometry

X-ray diffraction and total external reflection of X-rays (X-ray reflectometry) methods were used to study the successive stages of synthesis of epitaxial SiC films on Si (100) X-ray diffraction and total external X-ray reflection (XRD) methods were used to study successive stages of synthesis of epitaxial SiC films on Si (100) surfaces, (110) and (111) surfaces by the atom substitution method. The data on the transformation evolution of (100) surfaces were studied, (110) and (111) Si, into SiC surfaces. A comparative analysis of the X-ray structural quality of the SiC layers grown on Si by the atom substitution method with the quality of SiC layers grown by Advanced Epi by the standard CVD method. A modified technique for the total outer X-ray reflection method, based on measurements of the intensity of the reflected X-rays using a special parabolic mirror. It is shown that the method of total external reflection method makes it possible to obtain important information about the degree of surface roughness of SiC layers, the evolution of their crystal structure and plasmon energy in the process of Si to SiC conversion. Keywords: total external reflection, X-ray reflectometry, silicon carbide, plasmons.

Ionic liquid/TiO2 nanoparticles doped with non-expensive metals: new active catalyst for phenol photodegradation.

TiO2 nanoparticles were synthesized using 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMI·BF4) ionic liquid and doped with non-expensive metals Cu2+ and Fe3+ by the sol–gel method. The new generated photocatalysts had their morphological, textural and structural characteristics analysed by scanning electron microscopy and dispersive X-ray spectroscopy (SEM/EDS), transmission electron microscopy (TEM), Brunauer–Emmett–Teller analysis (BET), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and diffuse reflectance spectroscopy (DRS). The results showed two phases by XRD analysis, anatase (majority) and rutile (minority). The SEM micrographs exposed spherical TiO2 NPs/BMI·BF4 IL and compact layers for Cu2+ and Fe3+-doped TiO2 NPs in BMI·BF4 IL, the EDX confirmed only the presence of Ti, O, Fe and Cu. The BET and BJH analyses exhibited high porous TiO2 NPs/BMI·BF4 IL. The BET and BJH analyses confirmed that the pore diameter of mesoporous materials was between 12 and 16 nm with similar values for surface area (55–63 m2 g−1). The TEM images exhibited spherical shape nanoparticles with mean diameter of 20–22 nm. The DRS analysis and Tauc equation were applied to estimate the optical energy band gap of the photocatalysts. The energy band gap values of 3.1 eV, 3.32 eV, and 2.78 eV were obtained for TiO2 NPs/BMI·BF4 IL, 1% Fe3+-doped TiO2 NPs/BMI·BF4 IL and 1% Cu2+-doped TiO2 NPs/BMI·BF4 IL, respectively. Phenol photodegradation was realized using Cu2+ and Fe3+-doped TiO2 NPs/BMI·BF4 IL under UV/visible irradiation and quantified by HPLC-FLD. The phenol photodegradation was investigated by different concentrations of metal-doped TiO2 NPs/BMI·BF4 IL. The new active photocatalysts 1% Cu2+-doped TiO2 NPs and 1% Fe3+-doped TiO2 NPs/BMI·BF4 IL exhibited high catalytic activity (99.9% and 96.8%, respectively). The photocatalysts 1% Cu2+ and 1% Fe3+-doped TiO2 NPs/BMI·BF4 IL were also evaluated using industrial wastewater from the tobacco industry. The results showed 56.7% phenol photodegradation, due to the complexity of the tobacco matrix wastewater.

Identification of adulterants in artistic earth pigments using a multi-technique approach

The composition of natural earths from Kremer and others bought in different art shops in Lima was studied to determine their authenticity. They were analyzed by Raman Microscopy, X-ray Diffraction, X-ray Fluorescence, and Light reflectance. The results show that Kremer pigments have a natural origin, as they are rich in minerals and clay. By contrast, the pigments bought in Lima are synthetic and contain adulterants. One manufacturer used Cadmium-based pigments for adulteration in Umbers and Siennas, probably to obtain a color similar to the original. A second manufacturer used talc as a filler for adulteration in Sienna and Ochre. The third brand is probably a case of re-packaging construction pigments as art pigments. Manufacturers should label these pigments as Mars instead of Earth pigments, and their actual composition should be known prior to their use.

The significance of enhanced photocatalytic degradation of RhB on the synthesis, characterization, and effects of Ag doped CdS-WO2 Nano composites

A simple and sealing agent-free hydrothermal approach was used to fabricate the very modest Ag/CdSWO2 Nano composite in this article. Powder X-ray diffraction (XRD) and UV-vis diffuse reflectance (DRS) spectroscopy was used to characterise the synthesized Ag loaded CdS-WO2 Nano composite. Under visible light irradiation (VLI), the photocatalytic activity of synthesized photocatalysts was tested for the photodegradation of rhodamine B (RhB). pH, catalyst dose, oxidant dose, and irradiation time were the parameters employed to optimise the photocatalyst. A plausible reaction mechanism for improving Ag/CdS-WO2 photocatalytic activity has been postulated based on this. As a result, we have an inclination to assume that it could be a promising material for photodegradation of organic contaminants in wastewater.

Assessment of crystallographic and electronic phase stability of shock wave loaded cubic cerium oxide nanoparticles

Rapid progress has been documented during the last couple of years in understanding the crystallographic structural features of a few functional materials that have been achieved under dynamic shock wave loaded conditions. In this context, we report the crystallographic and electronic phase stability of shock wave loaded Cerium oxide nano-crystalline (CeO 2 NPs) material and the results have been evaluated by X-ray diffraction (XRD), Raman spectroscopy and ultra-violet diffuse reflectance spectroscopy (UV-DRS). XRD and Raman spectroscopic results show that the title material doesn't undergo any crystallographic phase transitions. UV-DRS spectral results demonstrate that the Ce 4+ ionic state is not affected by the impact of shock waves. The obtained FE-SEM micrographs provide the substantiation for the stability of the sample. Based on the observed results, the title material can be suggested for the making of medical glassware, spaceship windows and technological applications of coating.

Preparation of TiO2 Nanotube Using Anodization Method: Charactherization and Its Application for CO Sensor

Preparation of highly ordered TiO 2 nanotube arrays (HOTNAs) by anodization of Ti foil industrial grade in ethylene glycol electrolyte containing 0.3% of ammonium fluoride and 2% of water at 30 V for 90 minutes was conducted. The morphology structure, chemical composition, functional group, crystal phase, and optical properties of HOTNAs were characterized by field emission scanning electron microscope (FE-SEM), Energy Dispersive X-Ray (EDX),Fourier transform infra-red spectroscopy (FTIR), X-ray diffraction (XRD), and ultraviolet visible diffuse reflectance spectroscopy (UV/Vis-DRS). The well-ordered nanotube with vertically oriented structure was formed in the HOTNAs having size in diameter, length, and wall thickness of 48,0 nm, 1,8 µm, and 26,7 nm, respectively. The fabricated HOTNAs were evaluated for their sensing properties for CO detection. The results show that the fabricated HOTNAs were able to detect 2500 ppm of CO gas with response about 93,429 at operation temperature 150 ° C. This preliminary study of sensing performance demonstrates that the prepared HOTNAs under this study is potential and promising as a material sensor for CO detection.