X-ray Diffractomer Research Articles

Gleditsia sinensic extract as green corrosion inhibitor for N80 steel in 1 M HCl

The inhibition efficiency of gleditsia sinensic extract (GSE) as green corrosion inhibitor for N80 steel has been evaluated by weightlessness test, electrochemical impedance spectroscopy (EIS) study, Potentiodynamic polarization (PDP) measurement and Density Functional Theory (DFT) calculations in 1M HCl solution. Consequently, the inhibition efficiency of GSE is increased with the concentrations, immersion time and corrosion temperature (except 60 °C). After 144 h of immersion at 30 °C, the inhibition efficiency of GSE at a concentration of 500 mg/L was as high as 92.34 %. The adsorption process was spontaneous exothermic and conformed to Langmuir's law of adsorption, while Tafel's analysis showed that GSE is a mixed type of inhibitor. In addition, the corrosion products have been examined by scanning electron microscopy (SEM) analysis, X-Ray Diffractomer (XRD) testing, Fourier transform infrared spectroscopy (FTIR-ATR), UV-Vis spectroscopy and contact angle (CA) measurements. Furthermore, the corrosion inhibition mechanism has also been investigated.

Study on the effects of deep eutectic solvents as a reaction media on the micromorphology of hydrogen-substituted graphyne and its adsorption and electrochemical properties

The choice of reaction medium had a major influence on the micro-morphology, surface area and pore volume. The 18 hydrogen-substituted graphynes (HsGYs) were synthesized with various deep eutectic solvents (DESs) as the reaction medium by coupling polymerization. The results showed that DESs had the great influence on the morphology of HsGYs. Meanwhile, HsGYs with larger surface area can be obtained by using DESs with low density and hydrophobicity as the solvent. The structure and properties of materials were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectrometer, X-ray diffractomer, UV–Vis DRS spectrum, etc. The electrochemical and adsorption properties of samples with different morphologies were tested and analyzed. The cyclic voltammetry curves showed that the samples had good capacitance behavior. HsGY-1 and HsGY-3 had relatively small contact resistance through electrochemical impedance spectroscopy analysis. The adsorption experiments showed that HsGY-12 and HsGY-13, with the larger specific surface area (336.229 and 325.005 m2g−1), had the strongest adsorption performance to chrysophanol acid (28.5 and 29.2 mg g−1). By studying the influence of DESs as a reaction solvent on the properties of HsGYs, such as morphology and specific surface area, which provided reference for the synthesis method of polymers and its application in the fields of energy storage, separation analysis and gas adsorption.

Study on the protective effect of the dense slag layer on converter lining

AbstractIn this paper, the protective effect of the dense slag layer on the furnace lining is investigated through comparative sampling of residual bricks. The physical and chemical properties of the residual brick samples were tested, and the result showed that sample NO.1 had 7.9% higher bulk density, 37.6% lower apparent porosity, 41% higher flexural strength, and 14.3% higher compressive strength than sample NO.2. The residual carbon of sample NO.1 was normal, while the residual carbon oxidation loss rate of sample NO.2 was 36%. X‐ray diffractomer (XRD), optical microscope (OM), and EDS: scanning electron microscope‐Energy Dispersive Spectrometer (SEM+EDS) were adopted to study the physical phase composition, microscopic morphology, and mineral phase composition and distribution of the dense slag layer. The slag layer was found to be highly alkaline and oxidizing, with 58–73% RO phase, 17–26% phosphorus‐rich phase, and 6–16% base phase in the mineral phases. The FactSage 8.1 thermodynamic software was used to simulate and calculate the melting temperature of each mineral phase. The presence of the high melting point phase and RO phase in the dense slag layer is an important reason for its ability against high temperature and high oxidation. The formation of the dense slag layer was related to the saturated solubility of MgO. The results indicated that the extremely unstable saturated solubility of magnesia had a greater effect on the dissolution rate of magnesia particles. External temperature and oxidation changes are important factors affecting the saturated solubility of MgO in the slag layer, and reducing the internal‐external heat and mass transfer rate could effectively improve the service life of the furnace lining.

Improved immobilization of soil cadmium by regulating soil characteristics and microbial community through reductive soil disinfestation.

Cadmium (Cd) contamination arising from industrialization has attracted increasing attention in recent years. Reductive soil disinfestation (RSD) as an effective agricultural practice has been widely applied for soil sterilization. However, there is little research regarding RSD affecting Cd immobilization. Here, five treatments, namely untreated soil (CK), flooding-treated soil (FL), RSD with 2% ethyl alcohol (EA), 2% sugarcane bagasse (SB), and 2% bean dregs (BD) were designed to detect their performance for Cd immobilization in contaminated soils, and the change of soil properties and microbial communities were monitored. The results revealed that pH significantly increased in FL and RSD-treated soils, but was negatively correlated with the exchangeable fraction of Cd (EX-Cd), while Oxidation-Reduction Potential (Eh) significantly decreased in FL and RSD-treated soils, and was positively correlated with EX-Cd. BD treatment might contribute to the increase of CaCO3 as shown by X-Ray Diffractomer analysis and strongly decreased the EX-Cd in the soil, but increased the relative abundances of Firmicutes, Planctomycetes, Acidobacteria, and Gemmatimonadetes, which may promote Fe (III) reduction or induce resistance to Cd. Bacterial communities at the phylum and genus levels were closely related to Cd fraction. The FL and RSD treatments moderately altered bacterial specific functions, including iron respiration, which may contribute to remediation of Cd-polluted soil by Fe (III) reduction. Field experiments were conducted to confirm that BD treatment resulted in a significant increase in pH whereas the content of total available Cd was reduced in soils. Compared to the control, concentration of total available Cd of red amaranth, sweet potato, towel gourd, and cowpeas were reduced by approximately 46%, 74%, 72%, and 76% in a BD-treated field, respectively. Our study highlights the potential of RSD as an effective method for Cd immobilization in contaminated soils by improving soil characteristics and altering the composition of the microbial community.

Process Study on Surface Modification of Coral Hydroxyapatite

Objective: To explore process of modifying coral hydroxyapatite by nmZnO under different conditions, the final plan is to develop a porous artificial bone composite that combines the antibacterial properties of nano zinc oxide with the porous biodegradability of coral hydroxyapatite. Methods: Coral hydroxyapatite was modified by zinc nitrate sol-gel method at 70°C in weak acid environment. White granular porous composite materials were obtained by ultrasonic, rotary stirring, drying and calcination. The composition of the composite material is analyzed using X-ray diffractomer (XRD), using scanning electron microscopy (SEM) to observe and analyze changes in the surface appearance of composite materials, using energy dispersive X-ray spectroscopy (EDX) to observe and analyze the composition of the composite surface, the results of thermogravimetric analysis were used to study the decomposition temperature and other characteristics of the composite. Results: The sol-gel method can be used for antibacterial modification on CHA surface. When the mass ratio of coral hydroxyapatite, zinc nitrate and PEG-6000 is 48:4:5, the particle size and distribution of nano-zinc oxide particles are ideal, and uniformly distributed spherical ZnO nanoparticles can be observed under scanning electron microscopy. Conclusion: Coral hydroxyapatite surface could be modified by zinc nitrate sol-gel method. The particle size of nano zinc oxide is less than 100 nanometers. The agglomeration problem of nano-particles is solved; the porous structure of CHA are not destroyed.

Noncovalent modification of self‐assembled functionalized COF by PNIPAM and its properties of Pickering emulsion

AbstractBased on a facile and universal method using noncovalent bonding, here, polymer‐modified covalent organic framework materials (COFs) were rapidly prepared. PNIPAM‐modified COF (COF‐PNIPAM) was synthesized by electrostatic self‐assembly between COF prepared by low‐cost melamine and terephthalaldehyde and carboxyl‐terminated poly(N‐isopropylacrylamide) (PNIPAM) prepared via reversible addition‐fragmentation chain transfer polymerization. The carboxyl‐terminated PNIPAM was characterized by Gel Permeation Chromatography and Ultraviolet and Visible Spectroscopy (UV–vis). COF and COF‐PNIPAM were characterized by Fourier Transform Infrared Spectroscopes, Scanning Electron Microscope, Transmission Electron Microscope, X‐Ray Diffractomer (XRD), and Brunner‐Emmet‐Teller (BET) measurements. The results showed that the COF‐PNIPAM was successfully prepared. The Pickering emulsion properties of the COF‐PNIPAM in a water‐to‐toluene mixed system were studied, and when the water‐to‐oil ratio is 2:1, a stable emulsion can be obtained. However, the results show that the PNIPAM chains of COF‐PNIPAM nearly lose their temperature responsiveness.

Synthesis of Graphene Oxide Modified Magnetic Chitosan Having Skin-Like Morphology for Methylene Blue Adsorption.

In this work, a novel magnetic biomass adsorbent was synthesized by a simple method. The adsorbent prepared from chitosan, graphene oxide and CoFe₂O₄ with a 'skin-like' morphology had a strong adsorption capacity for methylene blue adsorption and was easily separated from the liquid. The synthesized samples were characterized by scanning electron microscope, energy dispersive spectroscopy, fourier transform infrared spectroscopy and X-ray diffractomer. The adsorption capacity of the adsorbent was evaluated. The various factors affecting the adsorption performance were explored. Meanwhile, the adsorption process was simulated by five kinetic models and four isotherm models. The adsorption process was well described by the Pseudo-second-order kinetic model and the Freundlich isotherm model. ΔG < 0, ΔH < 0 and ΔS < 0 indicate that the adsorption process was a spontaneous, exothermic and randomness decrease process. The adsorbents loaded with methylene blue could be desorbed by soaking in dilute hydrochloric acid. The adsorption-desorption cycle experimental results showed that the adsorbent had good reusability performance.

Mechanism and Kinetics of Ammonium Sulfate Roasting of Boron-Bearing Iron Tailings for Enhanced Metal Extraction

The large amount of boron-bearing iron tailings in China is a resource for metals that needs to be more completely and efficiently utilized. In this evaluation, the ammonium sulfate roasting process was used to make a controllable phase transformation to facilitate the subsequent extraction of valuable metals from boron-bearing iron tailings. The effects of roasting temperature, roasting time, the molar ratio of ammonium sulfate to tailings, and the particle size on the extraction of elements were investigated. The orthogonal experimental design of experiments was used to determine the optimal processing conditions. XRD (X-Ray Diffractomer), scanning electron microscope (SEM), and simultaneous DSC–TG analyzer were used to assist in elucidating the mechanism of ammonium sulfate roasting. The experimental results showed that nearly all Fe, Al, and Mg were extracted under the following conditions: (1) the molar ratio of ammonium sulfate to iron tailings was 3:1; (2) the roasting temperature was 450 °C; (3) the roasting time was 120 min.; and, (4) the particle size was less than 80 μm. The kinetics analysis indicated that the sulfation of metals was controlled by internal diffusion, with the apparent activation energies of 17.10 kJ·mol−1, 17.85 kJ·mol−1, 19.79 kJ·mol−1, and 29.71 kJ·mol−1 for Fe, Al, Mg, and B, respectively.

Optimization of heteroatom doped graphene oxide by deep eutectic solvents and the application for pipette-tip solid-phase extraction of flavonoids.

In order to improve the permeation and adsorption properties of graphene oxide, heteroatoms and deep eutectic solvent were introduced in this study. After being modified, the structural properties of graphene oxide were improved and the materials were applied to the determination of myricetin and rutin in tea sample by pipette-tip solid-phase extraction method. The materials were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-Ray diffractomer, energy dispersive spectroscopy, atomic force microscope, and specific surface area by Brunauer-Emmett-Teller N2 adsorption desorption analysis. Meanwhile, they were tested by static and dynamic adsorption. The result showed that the materials after modifying had better adsorption amount for myricetin and rutin than graphene oxide. The calibration graphs of myricetin and rutin in MeOH were linear over 0.10-500.00µg/mL, and the limits of detection and quantification were in the range of 0.00546-0.0182µg/mL and 0.00741-0.0247µg/mL, respectively. A reliable analytical method was developed for recognition targets in tea sample by DES modified nitrogen-doped graphene oxide with satisfactory extraction recoveries (myricetin 99.77%, rutin 98.14%). It was potential for the rapid purification of myricetin and rutin in tea sample combined with the pipette-tip solid-phase extraction.

Quasi Crystal Al (1xxx)/Carbonised Coconut Shell Nanoparticles: Synthesis and Characterisation

AbstractA novel synthesis of Al (1xxx)/carbonised coconut shell (CCS) nanoparticles using a ball milling technique was investigated. Initial Al/0.1%CCS powders of an average size of 51.06μm was milled for a period of 70 h. The milled particles at 16, 46 and 70 h were characterized using X-ray diffractomer (XRD), scanning electron microscope (SEM), transmission electron microscope and UV-Vis spectrophotometer. Result revealed that the calculated particle crystallite size from XRD aided with Scherrer’s equation is consistent with particle image sizes obtained from SEM aided with software. TEM image depicted variation in orientation and appearance of the Al 1xxx/0.1% CCS nanoparticles at different milling time. The wide variation in the particle size is attributable to different ball impacts on the individual powders during the ball milling process. Increased maximum absorbance observed with the milled particles when compared with the initial powders is an indication of quantum/nanosizing effect due to ball milling.

Phase transition and rheological behaviors of a novel cellulose solution with 4-(ω-(methylimidazole)alkyloxy)-4′-(cyano)-biphenyls as a mesogenic unit

4-(ω-(methylimidazole) hexyloxy)-4′-(cyano)-biphenyl (CbP) as a mesogenic unit was dissolved in 1-allyl-3-methylimidazolium chloride (AMIMCl) to generate cellulose side-chain liquid crystal. The influence of CbP on AMIMCl and cellulose/AMIMCl was investigated. Turbidity tests and Fourier-transform infrared spectra (FTIR) indicated that homogeneous solution of CbP/AMIMCl was formed and there was no chemical reaction between CbP and AMIMCl. The steady and dynamic shear measurements, polarized optical microscopy, differential scanning calorimetry and X-ray diffractomer were used to study the rheological behaviors and phase transition of cellulose/CbP/AMIMCl system. The results showed that there was an obvious liquid crystal phenomenon in cellulose/CbP/AMIMCl solution when the mass fraction of CbP in AMIMCl ranges between 2.5 and 3.5%, and solution temperature is 40–80 °C. The deviations from Cox–Merz rules suggested the destruction of intra- and intermolecular hydrogen bonds among cellulose, CbP and AMIMCl under shear deformation.

Inorganic-organic hybrid supramolecular material based on the highest connection of a Keggin arsenotungstate with electro-/photo-catalytic properties

An extraordinary supramolecular hybrid material based on the Keggin arsenotungstate, (Hbimb)3[AsW12O40]·H2O (1) (bimb=1,4-bis(imidazol-l-yl)butane) has been synthesized under hydrothermal condition and characterized by elemental analysis, infrared (IR), thermogravimetry (TG), X-Ray Diffractomer (XRD), and single-crystal XRD. In compound 1 the {AsW12O40} cluster is linked to 14 organic ligands through their surface oxygen atoms, which are further embraced by 20 polyanions analogs to form a tightly packed 3D supramolecular network with a (45·6)(452·638·8)(49·6)2 topology via strong hydrogen bonds and supramolecular interactions. Compound 1 represents the highest connectivity of Keggin supramolecular arsenotungstate, which exhibits electrocatalytic behaviors for reduction of H2O2 and high efficiency degradation capability for two typical dyes methylene blue (MB) and rhodamine B (RhB) under UV light.

Preparation and Characterization of Fe-N Co-doped TiO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and Its Effect on Photocatalytic Oxidation of 2-MIB in Water

The composite nanoparticles of un-doped, Fe-doped TiO2, Fe-N co-doped TiO2 were prepared by sol-gel method, and characterized by X-ray diffractomer, scanning electron microscope, and UV-Vis diffuse spectrometer. 2-methylisoborneol (2-MIB) was used as the model compound to investigate the photocatalytic activities of TiO2, and the effect of water quality on 2-MIB removal was also discussed. The results show that the prepared TiO2 was mainly anatase, and the band gap of TiO2 was narrowed and the absorption band moved to the visible direction after Fe3+-N3- doping. The best photocatalytic activity was achieved when 0.001% Fe-0.5% N co-doped TiO2 calcined at 500°C was employed, corresponding to the 2-MIB removal efficiency of 99.90% and pseudo-first order rate constant of 1.371 18 h-1 by photocatalytic oxidation process in 5h.

Preparation and structural characterization of TiO2 nanotube arrays on surface of orthopaedic titanium plate

Objective The TiO2 nanotube arrays, fabricated on the surface of orthopedics, was characterized, to provide carrier for orthopedics plant surface modification or coating, and seek a new way for the prevention and treatment of orthopedics plant infection. Methods By adjusting certain parameters, TiO2 nanotube arrays were fabricated on orthopedic titanium plate surface using the method of anodic oxidation, with glycerol system as electrolyte, orthopedics titanium plate as anode, and platinum electrode as cathode. TiO2 nanotube arrays were characterized. The element composition of TiO2 nanotube arrays was analyzed by X-ray photoelectron spectroscopy (XPS), and the morphological changes of TiO2 nanotube arrays was observed at high temperature (300 ℃) by X-ray diffractomer (XRD). Results With glycerol system as electrolyte, TiO2 nanotube array with diameter of about 100 to 200 nm and the length less than 3 μm can be fabricated on orthopedic titanium plate surface using anodic oxidation of 24 h. The surface of orthopedic titanium plate was changed from silver white to deep blue in the macroscopic view. The TiO2 nanotube array on orthopedics titanium plate surface was mainly composed of Ti element (75.88%), O element (20.16%), and F element (3.96%) by XPS analysis. TiO2 nanotube arrays morphology was stable when it was heated to 300 ℃ by muffle furnace. Conclusions The method of anodic oxidation can be applied to manufacture TiO2 nanotubes array on titanium plate surface. The array with stable morphology, the inner hollow shape, the bottom sealing, and a large specific surface area, can withstand high temperature, which can provide carrier for orthopedics plant surface modification or coating. Key words: Orthopaedic titanium plate; Preparation; Nanotube arrays; Structural characterization

Green water-based silver nanoplate conductive ink for flexible printed circuit

A green water-based silver nanoplate ink was developed for printed circuit board. The growth of the nanoplates was shown by the colour change of the solution. Silver nanoplates with the side length around 20–40 nm in the ink were identified by transmission electron microscope and X-ray diffractomer. The ink patterned on the flexible substrates (polyimide) turned into conductive pattern after sintered at 300°C for 1 hour. The morphology of the conductive patterns were characterised by scanning electron microscopy. After the sintering process, the resistivity of the conductive ink was 9.43μΩ.cm, while the adhesion to the substrate reached 4 B. Thermal gravity analysis was conducted to deduce the mechanism of the sintering process and the solid content of the ink. The application of the conductive ink was also discussed in this paper.

SnSb4/SiO2 multilayered thin films for phase change memory applications

SnSb4/SiO2 (SS/SiO2) multilayer thin films were prepared by using a radio-frequency (RF) magnetron sputtering method. The amorphous-to-crystalline transitions of SS/SiO2 films were investigated by in situ film resistance measurements. The thermal stability of amorphous SS thin films was greatly improved by the addition of SiO2. However, the thermal conductivity of SS/SiO2 multilayer thin films (0.23W/(m·K)) was much lower than that of monolayer SS thin film (1.37W/(m·K)). The result of X-ray diffractomer (XRD) measurement indicated that excess Sb composition existed in SS/SiO2 multilayer thin films, which could accelerate the phase change of the material. The multilayer configuration of SS/SiO2 multilayer thin film before and after crystallization was confirmed by transmission electron microscopy (TEM). Phase change memory (PCM) devices based on [SS(2nm)/SiO2(1.5nm)]14 thin film were fabricated and the low power consumption for the RESET operation was achieved (7.8×10−12J), which was significantly lower than that of GST cell (2.6×10−9J).

Nitrogen-Doped Ge10Sb90 Phase Change Thin Films for High-Temperature Data Retention and High-Speed Application

The amorphous to crystalline phase change of nitrogen-doped Ge10Sb90 thin films were investigated by in␣situ film resistance measurements. The thermal stability and data retention increased with the increase of N doping concentration. Compared with Ge10Sb90, a higher crystalline resistance of N-doped Ge10Sb90 thin films was obtained, which is beneficial for the reduction of RESET operation consumption of phase change memory. The analysis of x-ray diffractomer indicated that nitrogen doping can refine the grain size. The measurement of atomic force microscopy revealed that the crystallization was inhibited and the surface of thin films became smoother after N doping. A reversible phase transition was realized by the picosecond laser pulses and the switching speed of crystallization was measured.

Influence of N-doping on the thermal stability and switching speed of Zn15Sb85 phase change material

The phase change characteristics of nitrogen doping Zn15Sb85 thin films were investigated by in situ film resistance measurements. The crystallization temperature and activation energy for crystallization of thin films increased with the increase of nitrogen doping concentration. Compared with Zn15Sb85, nitrogen doping Zn15Sb85 thin films exhibited higher crystalline resistance, which is beneficial for the reduction of writing current of phase change memory. The analysis of X-ray diffractomer indicates that the films with doping of nitrogen can refine the grain size. A smaller density change before and after phase change for N-doped Zn15Sb85 thin films was obtained from X-ray reflectivity. The phase transition speed between the amorphous and crystalline state was investigated by the picosecond laser pulses.

Salt Spray Corrosion Resistance of Aluminized Coatings on X70 Pipeline Steel by Laser Thermal Radiation

The surface of X70 pipeline steel was aluminized by laser thermal radiation, the surface and interface morphologies of aluminized coatings were observed by SEM (scanning electron microscope), and energy spectrum of chemical elements in the bonding interface were analyzed by EDS (energy dispersive spectrometer). The element-distributions in the bonding interface before and after salt spray corrosion (SSC) were studied with plane scanning analysis, the phases of aluminized coating surface before and after SSC were analyzed with XRD (X-ray Diffractomer), and the effects of the aluminized coating on the SSC resistance of X70 pipeline steel were researched. The results show that the oxide aluminum coating is formed on X70 pipeline steel surface by laser thermal radiation, and the distributions of chemical elements are uniform, which are inter-infiltrated between the aluminized coating and the substrate resulting in forming metallurgical bonding. The pitting corrosion is relatively serious on the surface of X70 pipeline steel after SSC, and then the general corrosion is formed. The compact protection film of Al2O3 is generated on the sample surface after laser thermal radiation, which prevents from the contacting between corrosive medium Cl− and active Fe atom of the substrate, so as to improve the ability of SSC resistance of X70 pipeline steel.

Structure and properties of Tb0.3Dy0.7Fe2 alloys modified by surface nitriding

The surface of Tb0.3Dy0.7Fe2 alloys was modified by microwave electron-cyclotron-resonance chemical vapor deposition (MW-ECR-CVD) and ion implantation technology, respectively. The microstructure and corrosion resistance of nitrided layers were investigated by means of optical microscope (OM), X-ray diffractomer (XRD), auger electron spectroscopy (AES), and electrochemical workstation. After modified by MW-ECR-CVD, the nitrogen concentration of the nitrided layers decreases gradually with the depth increasing, while the nitrogen concentration modified by ion implantation process exhibits Gaussian distribution. The self-corrosion electric potential of the sample modified by ion implantation is higher than that modified by MW-ECR-CVD, which reveals that the samples modified by ion implantation process have a better resistance to corrosion. The magnetostrictions are assessed for the samples placed in the air for one year, which further confirms that the ion implantation process is more helpful to maintain the magnetostrictions.