X-ray Difractometer Research Articles

Photodegradation and Photoelectrodegradation of Methyl Orange and Methyl Violet Dyes using Graphite/PbTiO3 Composite under Visible Light Irradiation

The composite of Graphite/PbTiO3 has been synthesized for photocatalyst and photo-electrocatalyst of Methyl Orange (MO) and Methyl Violet (MV) degradation using a visible light source. The aims of the research were to study the influence of pH of the solution, iradiation time and kinetics study of MO and MV photodegradation, voltage of photoelectrodegradation of MO and MV. Composite of Graphite/PbTiO3 was synthesized by the sol-gel process with Titanium Tetraisopropoxide (TTIP) solution and Pb(NO3)2 powder as the precursors. Graphite/PbTiO3 composite was characterized using X-ray difractometer and FTIR spectrometer. The diffractogram of Graphite/PbTiO3 composite showed peaks at 2θ = 26.507o as a characteristic diffraction of Graphite, and at 2θ = 31.838o and 39.294o as those of PbTiO3. FTIR spectrum of Graphite/PbTiO3 composite exhibits vibration peaks of TiO2 at 609.5 – 420.5 cm-1 and those of Pb-O at 1337.66 cm-1 until 1395.56 cm-1. The photodegradation results showed that Graphite/PbTiO3 composite can degrade MO and MV optimally at a pH = 3. The photodegradation levels of MO and MV were 90.33% and 88.26% for 30 min of visible light radiation, respectively. The photodegradation of MO and MV were following the first-order reaction with a reaction rate constant of 0.4445 min-1 and 0.4244 min-1, respectively. Meanwhile, the photoelectrodegradation of MO was 96.50% at 10 volts and at pH 11, while the photoelectrodegradation of MV was 95.14% at 10 volts and at pH 7. When compared previous research, this result also shows excellent degradation MO and MV using Graphite/PbTiO3 under visible light irradiation. So that the use of visible lights provides an advantage over the use of UV light.

Adjustable luminescence properties of Eu3+ and Bi3+ codoped Ca3Zn3Te2O12 phosphor

Ca3Zn3Te2O12:Bi3+, Ca3Zn3Te2O12:Eu3+, Ca3Zn3Te2O12:Eu3+/Bi3+ are prepared successfully in air. The crystal phase, microscopic image, and optical properties of samples are investigated by the X-ray difractometer, scanning electron microscopy, and edinburgh steady-state FLS 980 spectrograph. The green emission of Ca3Zn3Te2O12:Bi3+ phosphor with excitation at 314 nm is observed and its broad emission spectrum in the range of 360 - 790 nm is attributed to the 3P1 → 1S0 transition of Bi3+ ion. Under excitation at 395 nm, the red emission of Ca3Zn3Te2O12:Eu3+ is found, the chromaticity coordinates are (0.6392, 0.3605), and its PL spectrum is in the rang of 575 - 750 nm because of the 5D0 → 7F0,7F1, 7F2, 7F3, and 7F4 transations of Eu3+ ion. The doping Bi3+ ion can affect the luminescence properties of Ca3Zn3Te2O12:Eu3+ phosphor. The adjustable color light from green to yellow of Ca3Zn3Te2O12:Eu3+, Bi3+ phosphor with excitation at 314 nm is revealed when Eu3+ concentration is changed from 0 to 12 mol%. When the excitation wavelength is 395 nm, Ca3Zn3Te2O12:Eu3+, Bi3+ phosphor only emits red light with emission spectrum in the rang of 575 - 750 nm. The energy level diagrams of Eu3+ and Bi3+ in Ca3Zn3Te2O12:Eu3+, Bi3+ are drawn, which is used to analyze the luminous mechanism of samples.

Preparation of Iron Oxide Magnetic Nanoparticles Natural Sand of Rokan River Synthesis with Ball Milling

Natural sand samples taken from the Rokan river, Riau Province, Indonesia, have been ball milled for 100 (one hundred) hours using a ball with a diameter of 1.5 cm and a constant rotation angular velocity of the tube of 100 revolutions / minute. Neodymium Iron Boron (NdFeB) strong magnets are used to separate magnetic minerals from their non-magnetic minerals. Magnetic induction was measured using the Pasco PS-2162 probe and its value was used to calculate the magnitude of magnetic susceptibility, it turns out that the magnetic susceptibility value of the 100-hour Ball Milling results increased significantly when compared to the magnetic susceptibility before Ball Milling, 968,245x 10−5 becomes 19.471x 10−5. The results of the X-Ray Fluorescence (XRF) test showed that the percentage of Fe milled increased from 1.669% to 35.187%, the particle size obtained from the scanning electron microscope (SEM) results was in the nanometer order of 78 nm and the X-Ray Difractometer (XRD) results.) shows that the magnetic nanoparticles produced are dominated by the hematite phase (α-Fe2O3) and the others are in the magnetite (Fe3O4) phase..

Evaluation of antibacterial and catalytic potential of copper-doped chemically exfoliated boron nitride nanosheets

Boron nitride (BN) nanosheets were prepared by chemical exfoliation method and incorporation of Cu as a dopant was achieved using hydrothermal route. Hexagonal phase of BN (h-BN) was detected using x-ray difractometer (XRD). Functional group analysis with fourier transform infrared spectroscope (FTIR) was employed to identify the chemicals used in the process, which was then further confirmed with energy dispersive x-ray spectroscopy (EDS) coupled with FESEM. Optical analysis undertaken with UV–vis. spectroscopy indicated absorption at UV region. Raman spectroscopy was used to acquire molecular fingerprints of BN molecules. Photoluminescence (PL) spectroscopy was carried out to study the exciton behaviour of samples in order to elucidate the electron migration and transfer rate. Field emission scanning electron microscope (FESEM) and high resolution transmission electron microscope (HRTEM) were employed to examine the morphology and structure of materials. The experimental results indicate that Cu-doped BN nanosheets possess excellent catalytic potential and superior antibacterial activity.

2D chemically exfoliated hexagonal boron nitride (hBN) nanosheets doped with Ni: synthesis, properties and catalytic application for the treatment of industrial wastewater

In this study, boron nitride nanosheets (BN–NS) were prepared through exfoliation of bulk BN powder and efficacious incorporation of Ni (dopant material) was achieved using hydrothermal methodology. Hexagonal phase of BN (h-BN) was detected using x-ray difractometer (XRD). The presence of used chemicals was identified by functional group analysis through fourier transform infrared spectroscope (FTIR), which indicated strong vibrations for B–N and B–N–B. Optical examination carried out through absorption spectra extracted from UV–vis. spectroscopy point out absorption at deep UV state. Raman spectra were obtained to affirm structural molecular fingerprints of BN. Excitons behavior was studied using photoluminescence (PL) spectroscope. Scanning (SEM) and transmission electron microscopes (TEM) were used to investigate morphological and microstructural features while interlayer spacing was evaluated using HRTEM micrographs. Purity of the obtained product was studied by means of EDS analysis. Catalytic activity was undertaken to inspect dye degradation which was evaluated spectrophotometrically. This study provides experimental validation to the use of two-dimensional materials, especially BN–NS, for rapid and enhanced degradation of dyes.

Seasonal Variations in the Grain Size Distribution and Mineral Composition of Suspended Particulate Matter of the Northern Dvina River

The paper presents the first results of a study of seasonal variations in the grain size distribution and mineral compositions of suspended particulate matter (SPM) of the Northern Dvina River. The SPM samples were collected every month during 2016–2017 at the outlet of the Kuznetchiha arm to Dvina Bay of the White Sea. The grain size fractions were separated by Petelin’s water-mechanical method with retention of fractions for subsequent analyses using an electron microscope, energy-dispersion microanalyzer, and X-ray difractometer. The results demonstrated that the pelitic and subcolloidal fractions predominated in the grain size distribution of river SPM, with subordinate coarser fractions. Seasonal variations in the SPM concentration and the total amount of detrital and clay minerals are influenced by river water discharge and achieved a maximum in high water periods (spring flood and partly at the end of summer–autumn heavy rains). The subcolloidal fraction in the March sample stands out in the fine fraction distribution. Its share in this sample was the highest among these fractions throughout the year. The reason is probably related to the highest content of fine dispersed detrital minerals in the fraction. The question of why this is encountered only in March remains open.

Biogenic production of silver nanoparticles by Enterobacter cloacae Ism26

A bacterial isolate capable of tolerating 30 mM silver nitrate (AgNO3) was recovered from soil contaminated with industrial waste. The isolate was identified by 16S rRNA as Enterobacter cloacae Ism26 (KP988024) and its capability to synthesize silver nanoparticles (AgNPs) was investigated. AgNPs were produced by mixing 1 mM AgNO3 solution with bacterial cell lysate under light conditions. The UV-Vis spectrum of the aqueous medium containing AgNPs exhibited a peak at 440 nm corresponding to the surface plasmon resonance of the AgNPs. The crystalline nature of the particles was confirmed by X-ray difractometer. High-resolution transmission electron microscopy revealed that the AgNPs were spherical and well dispersed and ranged in size from 7 to 25 nm. The average size range of the produced AgNPs was confirmed by dynamic light scattering. Fourier transform infrared spectroscopy revealed possible involvement of reductive groups on the surface of the nanoparticles. The biosynthesized AgNPs were stable for 6 months and inhibited both gram-positive and gram-negative bacteria. This work describes the exploitation of a low-cost biomaterial and an easy method for the synthesis of AgNPs with desirable and advantageous characteristics.

Characterization of Co:TiO2 Thin Film Grown by MOCVD Technique

The Co:TiO2 thin film was grown on n-type Si(100) by metal organic chemical vapor deposition (MOCVD) technique. The film’s growth parameters are as follow: substrate temperature of 450°C, bubbler temperature of 70°C, reactor chamber pressure of 2 militorr, and growth time of 2 hours. We characterized the structure of film by X-ray Difractometer (XRD), the morphology was characterized by Scanning Electron Microscope (SEM), and the fraction of Co atoms in TiO2 was characterized by Energy Dispersive x-ray Spectroscopy (EDS). The XRD result shows that the Co:TiO2 thin film is an anatase phase crystal dominated by A(213) orientation. Using Warren-Scherrer’s formula, the average grain size of Co:TiO2 is 169 nm. The SEM result shows that the Co:TiO2 film surface is quite coarse with relatively homogeneous grain shape. the average growth rate of Co:TiO2 film is 0.78 μm/h. In addition, the EDS result shows that Co atoms have been incorporated into the film replacing a portion of the Ti atoms by 0.085%.

HEAT TREATMENT OF ALUMINIUM MATRIX COMPOSITE (AMC) REINFORCEMENT ORGANOCLAY FOR AUTOMOTIVE APPLICATION

Aluminum Matrix Composites (AMC) reinforced montmorillonite (MMT) was performed using cationic surfactant , Artificial Aging and stir casting method. The content of MMT as a filler is 3%wt. Characterization were performed using Xray Difractometer, ultrasonic testing, SEM, and Hardness Vickers. The results show increase in crystallographic parameter, decrease in density, shiffting in XRD pattern and increase in hardness.Keywords: metal, composite, matrix, aluminum, AMC, MMC, organoclay, heat treatment MMT, artificial aging,stir casting, automotive

Zeolit Sintetis Terfungsionalisasi 3-(Trimetoksisilil)-1-Propantiol sebagai Adsorben Kation Cu(II) dan Biru Metilena

The more commonly used method for making synthetic zeolite from kaolin is hydrothermal method. This research tested a sol-gel method in processing synthetic zeolit using kaolin as the basic ingrediant. The synthetic zeolite derived from the sol-gel method was then characterized using X-ray Difractometer and Scanning Electron Microscope, which found resulting products zeolite-A, zeolite Y and sodalite. The adsorption ability of the synthetic zeolites was tested using Cu(II) and methylene blue. Functionalization of the synthetic zeolites by 3-(trimetoksisilil)-1-propantiol was done to increase adsorption capacity. Zeolite A modified by 3-(trimetoksisilil)-1-propantiol had the greater capacity to adsorb methylene blue at 30.11 mg/g. The adsorption isotherms of all the synthetic zeolites approached the Langmuir form. The adsorption energy off all synthetic zeolites approached the chemical adsorption.DOI: http://dx.doi.org/10.15408/jkv.v0i0.5144

Physico-thermal characteristics and health risk evaluation of randomly selected brake pads in the Nigerian market

Brake pads are safety element used with other components in the braking system to control the stability of the vehicle. However, affluence of myriads of brake pads in Nigeria and the extensive brake-fade related traffic accident have led to questioning the potential safety and health hazard of the brake pads in the market. In this study, four commercial brands of brake pads commonly used were purchased and assessed. The friction linings were chiseled from the back plates and coded as AU, SN, TY and SM. The material compositions of the linings were assessed though X-Ray Difractometer; density was determined using water displacement method; shear strength, using a Tensometer; thermal conductivity by applying Fourier’s Law of Heat Conduction, and thermo-gravimetric analysis, by controlled heating. The results showed that the lining materials contained copper, zinc, manganese, iron, lead and aluminium in certain proportions. Furthermore, all the linings began to decompose gradually near 400 o C; AU exhibited the highest thermal conductivity (2.71 W/m. K) while SM had the lowest (2.26 W/m. K); the highest true density (3.09 x 10 3 kg/m 3 ) was found in TY while the lowest (2.04 x 10 3 kg/m 3 ) was found in SM. The shear strength of TY and AU were 55.10 and 54.22 MPa respectively; while SM was 36.54 MPa. It was established that the physical and thermal characteristics of the pads were similar to that found in literature, but -their material composition presented serious hazard to health. Keywords: Physico-thermal, Brake Pads, Health Hazard, Friction Material, Composites, Automobile

EFFECT OF USING PITAYA PEEL AS DYE-SENSITIZER AND DYE MOLECULES IN ELECTROLYTE FOR PHOTOELECTROCHEMICAL REACTION

Natural dye sensitizer in photoelectrochemical shows a great potential in improving the efficiency of metal oxide semiconductor especially Titanium dioxide (TiO2) due to its prominent in absorbing visible light and also low cost. In this work, the effect of using pitaya peel as natural dye sensitizes to TiO2 has been studied through characterizations analysis and PEC test. The bare TiO2 thin films were fabricated on Fluorine-doped tin oxide (FTO) glass substrate by doctor blade method meanwhile dyesensitized TiO2 thin films prepared by immersion of TiO2 in the dye extracts. The fabricated thin films were characterized with Scanning Electron Microscopy (SEM), X-ray difractometer (XRD), UV-Vis spectrophotometer and photoelectrochemical analysis. The surface of TiO2 was porous and uniform meanwhile dye particles could not been observed due to very small size. The energy band gap of dye-sensitized TiO2 from the UV-Vis spectrum is 2.1 eV which is smaller than bare TiO2 (3.7 eV). Meanwhile, photoactivities of dye-sensitized TiO2 has the highest compared to bare TiO2 photoelectrodes which is 127μA/cm 2 in 6.25% v/v of pitaya dye in the electrolyte.

Structural, Optical, Electrical and Magnetic Properties of Ti0.9Co0.1O2, Ti0.9Cr0.1O2, Ti0.9Cr0.04Co0.06O2

Three samples of dilute magnetic semiconductors (DMS) have been prepared by solid state reaction method at sintering temperature of 950°C for 5hours. Their structural, optical, electrical and magnetic properties are optimized by X-Ray Difractometer (XRD), UV-Visible spectrophotometer (UV-Vis), Four point probe method and Vibrating sample magnetometer (VSM) measurements respectively. Surface morphology has been studied by using scanning electron microscope (SEM). Structural analysis showed that a single phase Rutile structure has been attained while Optical and resistivity measurements confirmed their semiconducting behaviors. Magnetic measurements showed weak Ferromagnetic and Paramagnetic behaviors at room temperature.

Investigations of Structural, Optical, Electrical and Magnetic Properties of TiO2 Based Dilute Magnetic Semiconductors Doped with TM where (TM= Fe0.1, Cr0.1, Fe0.06Cr0.04)

Three samples of dilute magnetic semiconductors (DMS) have been prepared by solid state reaction method at sintering temperature of 1000°C for 5hours. Their structural, optical, and magnetic properties are optimized by X-Ray Difractometer (XRD), UV-Visible spectrophotometer (UV-Vis) and Vibrating sample magnetometer (VSM)measurements respectively. Surface morphology has been studied by using scanning electron microscope (SEM). Structural analysis showed that a single phase Rutile structure has been attained while Optical measurements confirmed the semiconducting behaviors. Magnetic measurements showed weak Ferromagnetic and Paramagnetic behaviors at room temperature.

Influence of β-cyclodextrin on Cefixime Stability in Liquid Suspension Dosage Form

Cefixime is a third generation of cefalosporin antibiotic which is easily to hydrolize in water and usually prepared in the form of tablet and dry suspension dosage form. Formation of active ingredient in the form of inclusion complex was one of the methods which can be employed to increase its stability to hydrolytic degradation.The purpose of this study was to evaluate the stability of cefixime-β-cyclodextrin inclusion complex in liquid suspension dosage form. The Inclusion complex of cefixime with β-cyclodextrin were prepared by utilizing of kneading and freeze drying method with weight ratio of 1:1, 1:2 and 1:3. The Inclusion complex formation were confirmed by infrared spectroscopy (FTIR), powder X-ray difractometer (PXRD) and Scanning Electron Microscopy (SEM). The formulation of cefixime liquid suspensions were prepared in the citrate buffer pH of 3.5 for pure cefixime, physical mixture of cefixime with β-cyclodextrin and inclusion complex from each method. Further studies werestability tested for each formulae of cefixime in liquid suspension in 40°C and 75% RH and the remaining concentration of cefixime were determined by HPLC method. The best ratio for formation of inclusion complex was showed by ratio cefixime: β cyclodextrin 1:2. Stability test of cefixime liquid suspension showed that the stability of cefixime in inclusion complex made by freeze drying method decreased the stability instead of increased cefixime stability. Meanwhile there was no differences between stability of pure cefixime, its physical mixture with β-cyclodextrin and inclusion complex made by kneading. Thus, the preparation of cefixime-β-cyclodextrin inclusin complex was not effective in achieving the enchangement of cefixime stability.

Structural evaluation and animal implantation of porous eggshell wastederived hydroxyapatite graft as bone substitution

The development of hydroxyapatite graft with high economically value is needed for orthopedic practice in developing countries. Eggsell waste is well known as natural substance for calcium resource. It has been used as raw material in producing hydroxyapatite. This study was conducted to synthesize porous hydroxyapatite from eggshell waste and evaluate its activity as bone substitution. The porous hydroxyapatite graft was manufactured from eggshell and sugar as a raw material using hydrothermal process. The porous eggshell waste-derived hydroxyapatite (EW-HAP) graft was characterized using X ray difractometer (XRD) and analytical scanning electron microscope (SEM) and compared with commercial hydroxyapatite (HAP) JCPDS 09-432 graft (Bangros®) as standard. The porous EW-HAP graft obtained was then implanted on critically sized femoral defects surgically created in the right thigh of male Wistar rats (Rattus norvegicus) with Bangros® as control. Radiological examination using XRD and histological examination using hematoxyline-and-eosin staining of the bone femour were performed at 28 days after implantation. The results showed that the XRD pattern for EW-HAP was likely similar with the HAP standard. However, the SEM examination showed that the pasticle size of EW-HAP graft (2.5-3 μm) was higher than those HAP standard graft (1.5-2 μm). Radiographs according to the International of Limb Salvage (ISOLS) radiological evaluation system between EW-HAP graft (6.1 ± 1.45) and HAP control graft (6.9 ± 2.10) was not significantly different (p>0.05). Moreover, histological examination according to Lane and Shandu scoring system between the both graft (4.0 ± 0.94 versus 4.4 ± 0.92) was also not significantly different (p>0.05). It can be concluded that the structure EW-HAP graft is similar with HAP graft standard. The both grafts have also equal outcome as bone substitution.

Investigations on Surface Characteristics of Heat Treated Tool Steel after Wire Electro-Discharge Machining

In the material removal process, the workpiece surface undergoes various changes. The heat treatment process improves the material properties, whereas the white layer, which is a resolidified oxidized layer on the machined surface, affects the surface roughness and fatigue life of the component. In this work, the change in metallurgical properties and surface topography due to the heat treatment of AISI D2 tool steel after wire electro discharge machining (WEDM) is investigated. The test specimens were prepared by milling and then conventionally heat treated before machining with WEDM process. The surface characterization was conducted using a scanning electron microscope (SEM) and an X-ray difractometer. Additionally, surface roughness measurements and hardness test were also carried out. The observations based on microstructural changes and the droplets forming recast layer are found to influence the surface roughness, hardness, and white layer thickness of the wire electro-discharge machined surface of the tool steel.

High-precision X-ray diffractometer on the base of acoustic monochromator

A new scheme for X-ray difractometer based on acoustic monochromator has been developed and created. The advantages of the new diffractometer are high-level of X-ray monochromaticity, high intensity of diffracted waves, high density of energy flow, and the absence of background.

Application of artificial neural network for prediction of Pb(II) adsorption characteristics

The adsorption of Pb(II) onto the surface of microwave-assisted activated carbon was studied through a two-layer feedforward neural network. The activated carbon was developed by microwave activation of Acacia auriculiformis scrap wood char. The prepared adsorbent was characterized by using Brunauer-Emmett-Teller (BET) surface area analyzer, scanning electron microscope (SEM), and X-ray difractometer. In the present study, the input variables for the proposed network were solution pH, contact time, initial adsorbate concentration, adsorbent dose and temperature, whereas the output variable was the percent Pb(II) removal. The network had been trained by using different algorithms and based on the lowest mean squared error (MSE) value and validation error, resilient backpropagation algorithm with 12 neurons in the hidden layer was selected for the present investigation. The tan sigmoid and purelin transfer function were used in the hidden and the output layers of the proposed network, respectively. The model predicted and experimental values of the percent Pb(II) removal were also compared and both the values were found to be in reasonable agreement with each other. The performance of the developed network was further improved by normalizing the experimental data set and it was found that after normalization, the MSE and validation error were reduced significantly. The sensitivity analysis was also performed to determine the most significant input parameter.

Preparation and Characterization of γ-AgI in Superionic Composite Glasses (AgI)<sub>x</sub>(AgPO<sub>3</sub>)<sub>1-x</sub>

The γ-AgI phase was stabilized at room temperature in the composites glasses (AgI) x (AgPO 3 ) 1-x with x = 0.6 and 0.7 via rapid quenching of their molten mixture. The measurement of the crystal structure has been carried out using an X-ray Difractometer at the Physics Departement of Ibaraki University, Japan. The micro strain and crystal size are derived from Hall’s equation. The X-ray diffraction pattern shows some Bragg peaks that correspond to the crystalline γ-AgI. By increasing the concentration of AgI, the peak width becomes more narrow and the position shifts to the higher angle. This indicates that the crystalline size and microstrain are increasing. The increase of micro strain (η), and particle size (D) will increase the ionic mobility, thus increasing the ionic conductivity. It is concluded that solidification process on melt AgI into glass matrix AgPO 3 not only decreases the micro strain and the particle size, but it also increases the ionic conductivity.