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The pressure-induced phase transformations of rare earth orthophosphates (REPO4s) have become increasingly relevant in ceramic matrix composite (CMC) research; however, understanding of the shear-dependence of these transformations remains limited. This study employs diamond anvil cell experiments with three pressure media (neon, KCl, sample itself/no medium) to systematically assess the effect of shear on the phase transformations of TbPO4. Results show a lowering of the TbPO4 transformation onset pressure (Ponset) as well as an extension of the xenotime–monazite phase coexistence range under non-hydrostatic conditions. The TbPO4 Ponset under no medium (4.4(3) GPa) is the lowest REPO4 Ponset reported to date and represents a ~50% drop from the hydrostatic Ponset. Enthalpic differences likely account for lower Ponset values in TbPO4 compared to DyPO4. Experiments also show scheelite may be the post-monazite phase of TbPO4; this phase is consistent with observed and predicted REPO4 transformation pathways.

The current experimental work uses die casting, a liquid processing method, to create functionally graded material (FGM). To reduce the production of undesired intermetallic compounds, the FGM samples were created both with and without interfacing foil during the procedure. Mechanical properties including impact strength and microhardness were examined throughout the manufactured sample's cross-section. In addition, the interfacial bonding of FGM samples with and without an interacting foil was determined by estimating the shear strength. Analysis of the samples using X-ray diffraction (XRD) and scanning electron microscopy (SEM) reveals the existence of compounds in the sample as well as the diffusion of Al and Zn particles from one side to the other. Compared to the FGM without foil, it is observed that the diffusion rate at the interface is regulated when the foil is present. In addition, it was found that, in contrast to pb foil, the inclusion of Ag foil limited the rate at which particles could move from one side to the other. Additionally, machining investigations are carried out at varying depths on both sides of the sample in the direction of the interface with the assistance of electric discharge machining.

Realizing stress-free inorganic epitaxial films on weakly bonding substrates is of importance for applications that require film transfer onto surfaces that do not seed epitaxy. Film-substrate bonding is usually weakened by harnessing natural van der Waals layers (e.g., graphene) on substrate surfaces, but this is difficult to achieve in non-layered materials. Here, we demonstrate van der Waals epitaxy of stress-free films of a non-layered material VO2 on mica. The films exhibit out-of-plane 010 texture with three in-plane orientations inherited from the crystallographic domains of the substrate. The lattice parameters are invariant with film thickness, indicating weak film-substrate bonding and complete interfacial stress relaxation. The out-of-plane domain size scales monotonically with film thickness, but the in-plane domain size exhibits a minimum, indicating that the nucleation of large in-plane domains supports subsequent island growth. Complementary ab initio investigations suggest that VO2 nucleation and van der Waals epitaxy involves subtle polarization effects around, and the active participation of, surface potassium atoms on the mica surface. The VO2 films show a narrow domain-size-sensitive electrical-conductivity-temperature hysteresis. These results offer promise for tuning the properties of stress-free van der Waals epitaxial films of non-layered materials such as VO2 through microstructure control.

Herein, we prepared the zinc oxide (ZnO) and silver doped zinc oxide (Ag-ZnO) nanoparticles (NPs) using Berberis aristata plant extract as a reducing, capping and stabilizing agent. The x-ray diffraction (XRD) pattern confirms the formation of pure hexagonal wurtzite structure for both the samples with P4mm space group. The crystallite size reduces from 21.313 nm to 18.179 nm with the Scherrer technique with doping of Ag ions on ZnO NPs, while the Williamson Hall (WH) approach likewise demonstrates a decrease in crystallite size from 26.602 nm to 21.522 nm. The lattice strain increases from 0.0031 to 0.0064, indicating the presence of Ag-ions in the crystal lattice of ZnO NPs. For both samples, the metal-oxygen bond formation is supported by the Fourier Transform Infrared (FTIR) spectra. For ZnO, the peak in the UV-visible spectrum is approximately around 365 nm, but for Ag-ZnO, two peaks are observed around 235 nm and 360 nm. With the Ag doping, the bandgap increases from 3.01 eV to 3.02 eV. Transmission Electron Microscopy (TEM) micrographs show the formation of crystalline particles and Field Emission Scanning Electron Microscopy (FESEM) pictures show the formation of aggregated NPs with a spherical shape. Energy Dispersive x-ray Spectroscopy (EDX) and x-ray Photoelectron Spectroscopy (XPS) demonstrate the chemical purity of both the samples. The antibacterial activity of ZnO NPs was highest against Staphylococcus aureus i.e., 15 ± 0.53 mm, whereas, for Ag-ZnO NPs the highest activity was against Salmonella typhi i.e., 19 ± 0.53 mm.

Interest in the deformation behavior and phase transformations of rare earth orthophosphates (REPO4s) spans several fields of science—from geological impact analysis to ceramic matrix composite engineering. In this study, the phase behavior of polycrystalline, xenotime DyPO4 is studied up to 21.5(16) GPa at ambient temperature using in situ diamond anvil cell synchrotron X-ray diffraction. This experiment reveals a large xenotime–monazite phase coexistence pressure range of 7.6(15) GPa and evidence for the onset of a post-monazite transformation at 13.9(10) GPa to scheelite. The identification of scheelite as the post-monazite phase of DyPO4, though not definitive, is consistent with REPO4 phase transformation pathways reported in both the experimental and the computational literature.

Composites based on Zr65Cu17.5Ni10Al7.5/PTFE (polytetrafluoroethylene) with silane were prepared by ball milling with subsequent thermal pressing. Silanization was performed in the alcoholic solution with metallic glass powder. Different composites, 30/70 and 50/50 with silane, were prepared. During ball milling, Zr2Cu and Zr2Ni intermetallic phases were formed. The Zr-based metallic glass had a large supercooled region, and the melting point of the 30/70 and 50/50 composites with silane was near to the melting point of PTFE. The 50/50 composite (silane) had the highest thermal conductivity compared to the 30/70 composite samples. The incorporation of silane in metallic glass/polymer was investigated by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analysis. Thermogravimetric analysis (TGA) showed the thermal stability of the composite samples up to 450–460 °C. It was also concluded that the 50/50 composite with silane has better thermal stability than the 30/70 composite with silane. The addition of silane in 30/70 and 50/50 composites increased the thermal conductivity compared to the composites without silane.

In the present study the structural and compositional analysis of gallstones was carried out by various characterization techniques. Also, the utility of the study was evaluated on how the findings can enhance the treatment and dissolution therapies of gallstones? Gallstones from the Jharkhand region were analyzed both structurally as well as chemically using Field emission scanning electron microscope (FESEM) and Energy-dispersive X-ray spectroscopy, inductively coupled optical emission spectrometry (ICP-OES), Carbon hydrogen and nitrogen analyzer (CHNS), Nuclear magnetic resonance (NMR), Thermal gravimetric analysis (TGA) and Differential Thermal Analysis (DTA) and other instruments. The content of heavy metal was represented statistically as a mean with standard deviation. FESEM analysis unveiled the crystal and globular structure of cholesterol and pigment gallstones respectively. Through ICP-OES analysis metals such as Fe, Mn, Cu, Pb, Cr, Zn etc. were detected in gallstones. FTIR and XRD analysis confirmed the presence of cholesterol and calcium carbonate and other compounds in mixed stones and calcium bilirubinate and bilirubin in pigment gallstones. NMR analysis revealed the presence of monohydrate cholesterol (Crystalline) in Cholesterol and mixed gallstones. Mixed gallstones were found to be predominant in this region in contrast to pigmented stones that were prevalent earlier. The present study uncovered the current composition and content of different heavy metals in gallstones of Jharkhand region which can be instrumental in enhancing the dissolution therapies for gallstone treatment. This can serve as a major tool for practitioners for gallstone treatment and change the way they are looked at. [ABSTRACT FROM AUTHOR]

TiO2 nanopowder is prepared by simple sol-gel method using starting material as titanium isopropoxide with methanol and annealed at 600°C, 700°C and 800°C for 1 hour in air. X-ray diffraction pattern revealed the presence of both anatase and rutile phase in TiO2 specimens annealed at different temperatures. It is observed that the content of rutile phase and crystallite size increases with increase in annealing temperature. Scanning electron microscopy (SEM) is used to study surface morphology of TiO2 specimens annealed at different temperatures. Using Tauc plot it is observed that energy band gap decreases with increase in annealing temperature. I-V curve of TiO2 specimen shows that current increases with increase in annealing temperature. The preparation method is optimized by changing the concentration of titanium isopropoxide which leads to mixed phase (anatase and rutile) TiO2 nanopowder with a lower energy band gap value which may play an important role in gas sensing applications.

In this work, the biomedical applicability and physical properties of magnesium-based metallic glass/polycaprolactone (PCL) composites are explored. The composites were fabricated via mechanical alloying and subsequent coextrusion. The coextrusion process was carried out at a temperature near to the supercooled liquid region of the metallic glass and the viscous region of the polymer. The structures, as well as thermal and mechanical properties of the obtained samples were characterized, and in vivo investigations were undertaken. The composite samples possess acceptable thermal and mechanical properties. Tensile tests indicate the ability of the composites to withstand more than 100% deformation. In vivo studies reveal that the composites are biologically compatible and could be promising for biomedical applications.

Solid-state thin film batteries utilize electrode and electrolyte components which are nanometers or micrometers thick, enabling the production of novel devices with new form factors. Here, in situ X-ray diffraction is used to carry out the first study of a solid-state thin film lithium-ion battery containing a solid-state LiPON electrolyte and Bi negative electrode. The structure-electrochemistry relationships in the Li-Bi system are revealed and details of cell construction, data collection, and data analysis is presented to guide for research.

In this paper, multi-walled carbon nanotubes are synthesized by arc-discharge and chemical vapor decomposition methods. Multi-walled carbon nanotubes are synthesized on thin film of nickel sputtered on silicon substrate by thermal chemical vapor deposition of acetylene at a temperature of 750°C. The flow of current in arc-discharge method varies in the range 50–200 A. Further arc-synthesized carbon nanotubes are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the results are compared with nanotubes grown by chemical vapor deposition method. XRD result shows a characteristic peak (0 0 2) at 26.54° corresponding to the presence of carbon nanotubes. SEM and TEM results give morphology of as-synthesized multi-walled nanotubes. TEM results indicate synthesis of well-graphitized carbon nanotubes by arc-discharge method. Dispersion of arc-synthesized nanotubes in SDS solution under the effect of different sonication times is studied. Dispersion of nanotubes in SDS solution is analyzed using UV–vis–NIR spectroscopy and it shows an absorption peak at 260 nm. It was found that with the increase in sonication time, the absorption peak in UV–vis–NIR spectra will increase and optimum sonication time was 2 hours. Functionalization of synthesized carbon nanotubes by H2SO4 and HNO3 acids has been studied and analysis of functionalized groups has been done using FT-IR spectroscopy and compared and the results are reported in this paper. FT-IR spectroscopy verifies the presence of carboxylic groups attached to carbon nanotubes. These functional groups may change properties of carbon nanotubes and may be used in vast applications of carbon nanotubes.

Polycrystalline nanoparticles of Al-doped and Ce-co-doped ZnO were processed through sol)gel co-precipitation. Crystallite sizes determined from XRD were in the range of 10.90 to 48.77 nm. FTIR spectra indicated a stretching mode of Zn-O bond. The insertion of Al and Ce at Zn-O site created Al-O and Ce-O bonds. UV-vis spectra favoured the formation of impurity levels by doping and co-doping. Their overlapping with the conduction band edge led to the reduction of band-gap. Blue-green emission which arises from radiative recombination of a photogenerated hole with an electron occupying oxygen vacancy was observed in photo)luminescence spectra. FESEM suggested granular growth in undoped ZnO which changed to diverse structures such as nano-bar and cluster of elongated grains. Significant improvement in room temperature ferromagnetism (RTFM) was noticed by co-doping of Ce in Al-doped ZnO. Formation of bound magnetic polarons (Ce3+-Vo-Ce3+) was the primary mechanism responsible for the improvement in RTFM. [ABSTRACT FROM AUTHOR]

The multiferroic Bi0.8Gd0.1M0.1Fe0.9Ti0.1O3, (where M = Ba (DB), La (DL) and Pb (DP)) has been synthesized by using solid-state reaction technique. Effects of Ba, La and Pb substitution on the structure, electrical and ferroelectric properties of Bi0.8Gd0.1M0.1Fe0.9Ti0.1O3 samples have been studied by performing X-ray diffraction, dielectric and magnetic measurements. The crystal structures of the ceramic samples have a tetragonal phase. The vibrating sample magnetometer (VSM) measurement shows a significant change in the magnetic properties of Ba-doped Bi0.8Gd0.1M0.1Fe0.9Ti0.1O3 as compared to La- and Pb-doped ceramics. It is seen that coercive field (HC) and remanent magnetization (MR) increases with Ba-doped ceramics but decreases for La- and Pb-doped ceramics.