X-ray Diffractometry Results Research Articles

Lanthanide ion exchange modulated via crystalline phase transition of a mixed-metal coordination polymer based on bis(4-nitrophenyl) phosphate

We previously reported that the CeL3 [L = bis(4-nitrophenyl) phosphate] coordination polymer (CP) exhibits exceptionally large differences in ion exchange selectivity toward neighboring ions in the lanthanide series (Ln3+). Herein we aimed to elucidate the mechanism of the unique ion-exchange behavior of CeL3 by focusing on the formation reaction of a mixed-metal CP (MM-CP) and the phase transition between two crystalline types, which occurs during the course of the ion-exchange reaction. The results of powder X-ray diffractometry of the de novo-synthesized MM-CPs indicated that the Ln3+-to-Ce3+ mixing limit, xlim, in the crystal is an important factor that determines the feasibility of the structural transition. Smaller Lu3+, Yb3+, and Tm3+ electrostatically interact with ligand molecules very strongly, which causes structural strain in MM-CP. Thus, the crystal-to-crystal structural transition tends to occur when the Ln3+ mixing ratio (x) is above xlim (∼0.2). The exchange of Ce3+ for Ln3+ (=Lu3+, Yb3+, and Tm3+) in the MM-CPs is further facilitated following structural transition because the crystalline structure formed after phase transition is known to prefer the heavy Ln3+ ions to Ce3+. In addition, the crystal lattice contracts during structural transition, and the intact CeL3 inside the particles is exposed to the solution phase, which may result in ion-exchange proceeding as a chain reaction. Hence, Ce3+-for-Ln3+ exchange is accelerated when x > xlim and disfavored when x < xlim. Consequently, large Ln3+-dependent differences in final reactivity are observed.

Characterization of Thermal and Hydrodynamic Properties for Microencapsulated Phase Using the SPSS Method

Thermal conductivity is the assets of a fabric that conducts warmness. Lower than materials with higher thermal conductivi-ty Materials with thermal conductivity are low throughout Heat transfer occurs at cost. This characteristic the temperature is estab-lished and its reciprocal heat resistance The 3 primary thermal houses Foods have accurate heating, thermal conductivity and Heat dif-fusion. Specific heat is using 1°C The temperature of a kg substance The amount of heat required to raise Three simple warmth Treat-ments used in food safety include: Pasteurization, in which food is about sixty-two degrees Half an hour or seventy-two in Celsius15 to 17 seconds at °C treatment is provided; Hot filling, including liquid Keeping foods and juices in containers are boiled earlier than; And Steam treatment under pressure carried out inside the processing ap-proach, Thermal characterization of PCM Evaluation of melt-ing temperature by a differential scanning calo-rimeter (DSC) to det done, and the heat of fusion of the fabric (latent heat) is analyzed. Perkin Elmer Dia-mond DSC; The consequences are analyzed the use of Pyris 7.0 software. Thermal properties relate to a fab-ric's re-action when heat is carried out to a solid, a liquid, or a gasoline. This response may be an increase in temperature, a phase trade, a change in period or extent, the initiation of a chemical response, or a alternate in some other physical or chemical quantity. Research significance: To characterize the investigated fibers three methods are used suitable for evaluating the differences inside the systems of the fiber ad-ditives. FTIR spec-troscopy evaluation revealed High in Mezilaurusitauba and puriti fibre Extraction contents at 2920 and 2850 cm-1 May be associated with the best bands in, this Be careful when using pads and other pads means to be. Lignocellulosic Compare the crystallinity between fibers X-ray diffractometry results, Dipteryxodorata and guarava fiber are cellulose chains More in supplemental prepared formto see with FTIR spectroscopy Shows that are used. crystallinity, main to better crystallinity. The mixed consequences display that water related to lower amounts of extractives and better crystallinity and better crystallinity slows down the degradation pro-cess and increases the thermal stability of lignocelluloses fibres. Method: SPSS statistics is a multivariate ana-lytics, business intelligence, and criminal investigation data management, advanced ana-lytics, developed by IBM for a statistical software package. A long time, spa inc. Was created by, IBM purchased it in 2009. The brand name for the most recent versions is IBM SPSS statistics. Evaluation parameters: Eucalyptusgrandis, Pinuselliottii, Jute, Dipteryxodorata, Ramie, Sisal and Buriti. Result: The Cronbach's Alpha Reliability result. The overall Cronbach's Alpha value for the model is .744 which indicates 74% relia-bility. From the literature review, the above 50% Cronbach's Alpha value model can be considered for analysis. Conclusion: The Cronbach's Alpha Reliability result. The overall Cronbach's Alpha value for the model is .744 which indicates 74% reliability. From the literature review, the above 50% Cronbach's Alpha value model can be considered for analysis.

스퍼터링과 원자층 증착법으로 제작된 박막형 고체산화물 연료전지 환원극 기능층 특성 평가

In this study, Yttria-stabilized zirconia (YSZ) functional layers were applied with different thin-film fabrication process such as sputtering and atomic layer deposition (ALD) to enhance oxygen reduction reaction (ORR) for solid oxide fuel cells. We confirmed that the YSZ functional layer deposited with sputtering showed relatively low grain boundary density, while the YSZ functional layer deposited with the ALD technique clearly indicated high grain boundary density through scanning electron microscopy (SEM) and X-ray diffractometry (XRD) results. The YSZ functional layer coated with the ALD technique revealed that more ORR kinetics can occur using high grain boundary density than the functional layer deposited with sputtering. The peak power density of the SOFC deposited with ALD YSZ indicates 2-folds enhancement than the pristine SOFC.

On the Possible Nature of Armchair-Zigzag Structure Formation and Heat Capacity Decrease in MWCNTs.

Structural disorder and temperature behavior of specific heat in multi walled carbon nanotubes (MWCNTs) have been investigated. The results of X-ray diffractometry, Raman spectroscopy, and transmission electron microscopy (TEM) images are analyzed. The thermodynamic theory of the zigzag-armchair domain structure formation during nanotube synthesis is developed. The influence of structural disorder on the temperature behavior of specific heat is investigated. The size of domains was estimated at ~40 nm. A decrease in heat capacity is due to this size effect. The revealed dependence of the heat capacity of MWCNTs on the structural disorder allows control over thermal properties of nanotubes and can be useful for the development of thermoelectric, thermal interface materials and nanofluids based on them.

THE EFFECT OF MECHANICAL PROCESSING ON THE STRUCTURE OF CELLULOSE FROM HEMP

In the course of the research work, the influence of mechanical processing on the structural specificity of cellulose obtained by organo–solvent oxidation from cannabis, an annualraw material common in the East region, is considered. The features of the chemical structure and crystal structure of the modified cellulose were studied by the methods of IR-Fourier spectroscopy and X-ray diffractometry and surface morphology by the optical microscopy method. One solution to the widespread use of mechanical processing is to consider a new habit. The method of mechanical processing using a natural polymer modification is environmentally and cost-effective. Cellulose obtained by organo-solvent oxidation from a hemp was machined in a ball mill, using balls with a diameter of 10 mm, at room temperature, at a rotation speed of 300 rpm. It was confirmed that the chemical structure of the obtained cellulose has not changed using the IR spectrum. The results of X-ray diffractometry were processed by the Segal method, making sure that the crystallinity index (CI) increased from 58.6% to 65.2%. As a result, it turned out that mechanical activation using a ball mill increases the crystallinity index due to the destruction of amorphous parts without changing the chemical structure of cellulose. This result opens the way for the selective production of the really desired crystalline degree of cellulose by mechanical processing.

Structural, morphological, and optical properties of carbon nanoparticles unsheathed from date palm fronds.

Several studies have reported the synthesis of carbon nanoparticles (CNPs) by various methods. In this study, an easy one-step process to unsheathe CNPs from date palm fronds through a top-down ball milling method has been reported. The CNPs were characterized using various spectroscopic and microscopic methods to determine their structural and morphological features, optical properties, crystallinity, physicochemical properties, and particle stability. Transmission electron microscopy (TEM) revealed that the obtained CNPs' size ranged from 4 to 22 nm in a crystalline form. Scanning electron microscopy (SEM) confirmed their spherical shape, while the maximum photoluminescence (PL) intensity was recorded at 464 nm when excited at 375 nm. The unsheathed CNPs produced a good quantum yield (QY) of 3.24%. Furthermore, the CNPs exhibited high Raman ratios of ID/IG and I2D/IG with values of 0.59 and 0.04, respectively, verifying their multilayer crystalline graphitic nature. These Raman ratios also agree with the X-ray diffractometry (XRD) results. The CNPs' sp2 and sp3 carbon bonds were confirmed by X-ray photoelectron spectroscopy (XPS), with oxygen on the surface forming carboxyl and carbonyl groups with no other observable impurities. Furthermore, the extracted CNPs showed excellent PL properties for up- and down-conversion. These properties are exemplary for low-cost biomass with potential applications in biomedicine. Therefore, the extracted CNPs reported in this study have potential applications in optical imaging.

Preparation of La-Nd co-doped ZnO nanospheres and application on effluent treatment containing reactive dyes

Zinc oxide (ZnO) nanospheres and La-Nd co-doped spherical ZnO composite were prepared by solvothermal method with zinc chloride and urea, ethylene glycol (EG) as morphology controller, to obtain excellent photocatalytic effect and degradation of pollutants containing reactive dyes. The morphology, structure and chemical composition were described by scanning electron microscopy (SEM), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflection spectrum (DRS). The results showed that the size of La-Nd co-doped spherical ZnO about 130 nm, and the XRD results showed sharper characteristic peak. Meanwhile, the band gap of 2%La-1%Nd co-doped ZnO reduced from 3.23 eV to 2.97 eV. The degradation of effluent treatment containing reactive dyes like reactive red 24 (RR24) or reactive yellow 145 (RY145) was reached 99.99% under UV illumination for 75 min with 2%La-1%Nd co-doped ZnO as catalyst, which showed remarkable photocatalytic performance. After 120 min, removal efficiencies of chemical oxygen demand (COD) and total organic carbon (TOC) for RR24 discharge liquid attained 76.68% and 73.16% respectively, meanwhile, COD and TOC removal efficiencies for RY145 discharge liquid reached 76.32% and 72.36%.

Obtaining zeolite A from filtrate of zeolite LSX and its influence on the removal of heavy metals and organic pollutants in spent lubricating oil

Zeolites A was synthesized from alternate sources such as filtrate from synthesized zeolite LSX and aluminate solution extracted from bauxite which produced a very good yield. The synthesized zeolite type was characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). The synthesized product showed a high degree of crystallinity from the XRD results. When applied to a spent lubricating oil, the efficiency in removing the heavy metals was: 23.4% Fe, 96.8% Zn, 19.0% Cu, and 12.0% Cr. The saturates in the regenerated oil were 80% carbon, 4% residue, and 16% aromatics as compared to that of a commercial virgin oil that contained 84% saturates, 3% carbon residue, and 13% aromatics. This indicated that the spent oil can be reused.

Microstructure and optical properties of PbSe nanocrystalline films prepared by magnetron sputtering

PbSe nanocrystalline films were prepared using magnetron sputtering with different sputtering powers and deposition times. The obtained samples were characterized by X-ray diffractometry (XRD), field-emission scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), confocal Raman spectroscopy, UV–Vis–NIR spectroscopy, and spectrofluorophotometry. The XRD and XPS results show that the crystallization quality improves and the Pb/Se atomic ratio tends toward 1:1 with increasing sputtering power and deposition time. The morphology of PbSe particles varies from near-spherical to rod-like or cotton-like and then to triangular with increasing deposition time, consistent with the changed main growth orientation. The optical band gap of PbSe films decreases with increasing film thickness and grain size. A visible photoluminescence peak is observed at 655 nm, and its intensity strongly depends on the crystallization quality and morphology of PbSe particles, which is well consistent with the XRD and SEM results. Therefore, PbSe films with good luminescence performance can be obtained by adjusting sputtering power and deposition time.

Low-temperature growth of crystalline Tin(II) monosulfide thin films by atomic layer deposition using a liquid divalent tin precursor

In this study, better-quality stoichiometric SnS thin films were prepared by atomic layer deposition (ALD) using a liquid divalent Sn precursor, N, N′-di-t-butyl-2-methylpropane-1,2-diamido tin(II) [Sn(dmpa)], and H2S. A relatively high growth per ALD cycle (GPC) value of approximately 0.13 nm/cycle was achieved at 125 °C. Furthermore, crystalline SnS films could be grown from room temperature (25 °C) to a high temperature of 250 °C. Density functional theory (DFT) calculations were used to examine the surface reactions and self-limiting nature of the Sn precursor. Mixed phases of cubic (π) and orthorhombic (o) SnS films were deposited at low temperatures (25–100 °C), whereas only the orthorhombic phase prevailed at high growth temperatures (>125 °C) based on the complementary results of X-ray diffractometry (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) analyses. The optoelectronic properties of the SnS films were further evaluated by spectroscopic ellipsometry (SE) analysis. The results from the SE analysis supported the observed change from mixed π-SnS and o-SnS to o-SnS with increasing deposition temperature and allowed the determination of the energy bandgap (~1.1 eV) and a relatively broad semi-transparent window (up to 3000 nm). Overall, this new ALD process for obtaining a good quality SnS is applicable even at room temperature (25 °C), and we foresee that this process could be of considerable interest for emerging applications.

Contemporary heterostructures for solar cells improvement

Current investigation is focused on InxGa1-xP and InxAl1-xP epitaxial layers growth. Multicomponent nanoheterostructures are the main materials for a contemporary triple-cascade solar cell, and for perspective photovoltaic devices. The optimal InxGa1-xP and InxAl1-xP growth process characteristics are determined. InxGa1-xP epitaxial layers (with In & Ga varied on Ge), and InxAl1-xP layers (with Al & In varied on Ge and GaAs) are investigated. During investigation X-ray diffractometry was used. Based on results of X-ray diffractometry the lattice parameter and In / Ga / Al ratio in the structure were detected. Solid phase versus the gas phase composition correlation was found based on the lattice parameters. It is determined that diffraction X-ray peaks broadening can be used as a parameter for the heterostructure perfection analyze. For the InxGa1-xP solid solution (X = 45–53 %) and for InxAl1-xP solid solution (X = 46-51 %) a high quality of the single-crystal structure and a slight diffraction X-ray peaks broadening are detected.

Synthesis and characterization of niobium-doped fish scale-derived hydroxyapatite by physical ultrasound interference

Fish scales of the Arapaima gigas (pirarucu) species were heat-treated to obtain natural hydroxyapatite (HAp), and it was doped with niobium (Nb) by physical ultrasound interference to confirm an effective route to the production of Nb-doped HAp powders. The effect of ultrasound application on doping was investigated. The structure of the powders was elucidated using X-ray diffractometry (XRD), scanning electron microscopy, IR spectroscopy, and X-ray fluorescence spectroscopy (XRF). XRD results of Nb-doped HAp powders were compared with undoped natural hydroxyapatite and ICSD-26204 standard as controls. The crystallinity of Nb-doped HAp powders increased from 39% to 51% after the ultrasound application. IR spectroscopy confirmed hydroxyl, carbonate, and phosphate functional groups in the sample. Results obtained by XRF confirmed the ionic substitution of Ca for Nb with an average content of 1%. Therefore, the effectiveness of the synthesis route was confirmed to produce hydroxyapatite-niobium crystalline powder with physicochemical integrity as a potential biomaterial for bone implant application.

Investigation on physicochemical properties of graphene oxide/nano-hydroxyapatite composites and its biomedical applications

Graphene oxide/nano-hydroxyapatite (GO/nHAP) composites were synthesized by simultaneous titration method. The GO powder was uniformly dispersed ultrasonically in a solution containing Ca(NO3)2. It was co-titrated with (NH4)2HPO4, during which NH3·H2O was used to maintain pH of about 10. Transmission electron microscopy (TEM) showed that HAP had a drusy acicular crystal structure with 100–200 nm length in the composite. The Ca2+ ions were attracted by the negatively charged oxygen functional groups present on GO sheets. They also oriented the growth of hydroxyapatite preferentially along (112) plane, which was also consistent with X-ray diffractometry (XRD) results. According to X-ray photoelectron spectroscopic (XPS) results, the peak intensities of the C–O and C–C groups increased in the GO/nHAP composite. However, the number of –COO– and C–O–C groups was reduced as well as the position of peaks shifted due to electrostatic interactions. These results were also corroborated with Fourier transform infrared spectroscopy (FTIR). MTT assay indicated that GO/nHAP composites had a significant effect on proliferation of 293T cells and good biomimetic mineralization as shown by in vitro bioactivity assays. EDS spectroscopy confirmed that the Ca/P ratio in calcium phosphate deposits was 1.62, which was close to the ratio of 1.64 in natural bone. The biological performance of GO/nHAP composite proved it to be a promising candidate for bone regeneration and implantation.

Improving hysteresis of room-temperature air-quenching MAPbI3-xClx solar cells by using mixed-lead halide precursor

This work highlights the utilization of mixed-lead halide precursor for improvement of hysteresis in room-temperature air-quenching perovskite solar cells (PSCs). Room-temperature air-quenching method has been proved as an effective way to improve the morphology of perovskite thin films as well as the efficiency of the PSCs. However, the high hysteresis of the room-temperature air-quenching PSCs is still an obstacle to be overcome. By using mixed-lead halide precursor, the room-temperature air-quenching PSCs exhibited a low hysteresis effect index (HEI) of −0.032. The results of X-ray diffractometry (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), photoluminescence (PL), space charge limited current measurement (SCLC), and capacitance-voltage (C–V) measurement suggested that the improvement of the hysteresis of the room-temperature air-quenching PSCs can be ascribed to smooth film morphology and the low trap density contributed by the mix-lead halide precursor.

Stress–Corrosion Cracking of AISI 316L Stainless Steel in Seawater Environments: Effect of Surface Machining

To understand the effect of surface machining on the resistance of AISI 316L to SCC (stress–corrosion cracking) in marine environments, we tested nuts surface-machined by different methods in a seawater-spraying chamber. Two forms of cracks were observed: on the machined surface and underneath it. On the surface, cracks connected with the pitting sites were observed to propagate perpendicular to the hoop-stress direction, identifying them as stress–corrosion cracks. Under the surface, catastrophic transgranular cracks developed, likely driven by hydrogen embrittlement caused by the chloride-concentrating level of humidity in the testing environment. Under constant testing conditions, significantly different SCC resistance was observed depending on how the nuts had been machined. Statistical evaluation of the nut surface-crack density indicates that machining by a “form” tool yields a crack density one order of magnitude lower than machining by a “single-point” tool. Microstructural analysis of form-tool-machined nuts revealed a homogeneous deformed subsurface zone with nanosized grains, leading to enhanced surface hardness. Apparently, the reduced grain size and/or the associated mechanical hardening improve resistance to SCC. The nanograin subsurface zone was not observed on nuts machined by a single-point tool. Surface roughness measurements indicate that single-point-tool-machined nuts have a rougher surface than form-tool machined nuts. Apparently, surface roughness reduces SCC resistance by increasing the susceptibility to etch attack in Cl--rich solutions. The results of X-ray diffractometry and transmission electron microscopy diffractometry indicate that machining with either tool generates a small volume fraction (&lt; 0.01) of strain-induced martensite. However, considering the small volume fraction and absence of martensite in regions of cracking, martensite is not primarily responsible for SCC in marine environments.

Preparation and characterization of spiro-acridine derivative and 2-hydroxypropyl-β-cyclodextrin inclusion complex

The spiro-acridine derivative (E)-1′-(benzylideneamino)-5′-oxo-1′,5′-dihydro-10H-spiro[acridine-9,2′-pyrrole]-4-carbonitrile (AMTAC-01) is a synthetic compound with limited water solubility, which restricts its physiological activities and therapeutic applications. Hence, we investigated the complexation of AMTAC-01 with 2-hydroxypropyl‑β‑cyclodextrin (HPβCD) using the freeze-drying method. Complex formation was characterized by scanning electron microscopy, X-ray diffractometry(XRD), nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and fluorescence spectrophotometry. Additionally, molecular modeling and phase solubility studies were performed. Molecular modeling demonstrated the most stable inclusion model, and phase solubility studies indicated that AMTAC-01 and HPβCD formed a 1:1 inclusion complex with an apparent stability constant of 1145.3 M − 1. XRD and spectroscopy results suggest intermolecular interactions between AMTAC-01 and HPβCD, with the formation of a 1:1 inclusion complex demonstrating an amorphous pattern and alterations in band distribution intensities compared with free drug.

Co(OH)2 ELECTROCATALYST DECORATED ON TiO2 FILM FOR ENHANCED PHOTOELECTROCATALYTIC WATER OXIDATION

Recently, Co(OH)2 has gained much attention as a promising electrocatalyst. Herein, we synthesized Co(OH)2-decorated TiO2 film for electrocatalytic water splitting by a facile and low-cost electrochemistry method, which possessed enhanced performance for oxygen evolution reaction. The results of X-ray diffractometry, transmission electron microscope, scanning electron microscope and X-ray photoelectron spectroscopy verify the successful decoration of Co(OH)2 electrocatalysts onto the surface of TiO2. Moreover, photoelectrocatalytic measurements illustrate that the Co(OH)2-decorated TiO2 shows higher current density than pure TiO2 sample. The results obtained in this work give deep insights into the development of photoelectrochemical water splitting.

Two-Body Abrasion Behaviors Characterization of White Cast Iron with Various Chromium Concentrations

As-cast white cast iron specimens with chromium concentrations of 0, 2, and 4 wt% were prepared by melting and casting. Scanning electron microscopy and X-ray diffractometry results indicate that the composite phase consists of a hard phase (cementite) and a toughness matrix (pearlite) with a 28.8 ± 2% cementite volume fraction, which is a typical hypoeutectic structure. The cementite and pearlite microhardness increased with a higher chromium content. The maximum cementite microhardness was 1,054.23 HV. Two-body abrasive wear was measured under a higher impact load using a pin-on-disc tribometer. The effect of chromium content on the wear behavior of the cementite groove depth and width, roughness, chip peel off on the worn surfaces, and mass loss were investigated at an applied pressure of 1.83 MPa. With increasing Cr content, the roughness and mass loss decreased by 10.7 and 15.9%, respectively, and the wear resistance increased visibly. The break in abrasive SiO2 resulted in abrasive tip passivation during wear. As a result, the ratio of the depth–width of the parallel groove and the length–width of the worn chip decreased significantly.

Geopolymer Synthesis with Low Sodium Hydroxide Concentration

In this study, fly ash was utilized to synthesize geopolymer by activating with 4 M sodium hydroxide. Samples were cured at 120 °C for 6, 15 and 24 h, and they were aged for 7, 28 and 90 days. The degree of reaction was determined, and leaching tests were performed on all geopolymer samples according to US EPA TCLP method. The microstructural properties of samples were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD) and scanning electron microscope (SEM) techniques. Increase in both curing and aging durations resulted in higher compressive strength values. The results of leaching tests indicated that the metals were successfully immobilized. The major bonds of geopolymers were observed in FTIR spectrum. The intensity of the Al–O and Si–O asymmetric bonds increased with increase in curing duration. In XRD diffractograms, it was observed that all of the geopolymer samples had amorphous structure containing mainly two crystal phases. FTIR, XRD and SEM results revealed that geopolymerization was achieved in these synthesis conditions despite low molarity.

A study on the effects of varying concentrations on the properties of ytterbium-doped cobalt selenide thin films

Cobalt selenide thin films were synthesized and doped with ytterbium via electrodeposition technique. The morphological, structural, elemental and optical properties were obtained using scanning electron microscopy (SEM), x-ray diffractometry (XRD), energy dispersive x-ray spectrophotometry (EDX) and ultraviolet–visible spectroscopy (UV–vis) respectively. SEM results revealed round-like shaped nanograins while a hexagonal crystal structure was obtained from the XRD results. EDX spectrum revealed the deposition of the basic elements in the films deposited. Optical analysis showed high transmittance and reduced band gap energies of the cobalt selenide films upon doping with ytterbium. The obtained films serve as potential materials for optical and photonic devices.