Increase of Solid Polymer Electrolyte Ionic Conductivity Using Nano-SiO2 Synthesized from Sugarcane Bagasse as Filler

The synthesize of solid polymer electrolyte (SPE) based on polyethylene oxide (PEO), NaClO4 and nano-SiO2 was carried out by solution cast technique. Nano-SiO2 was synthesized from sugarcane bagasse using sol-gel method. FTIR analysis was carried out to investigate the bonding between nano-SiO2 and PEO/NaClO4. The morphology of the SPE was characterized using SEM. XRD and DSC analysis showed that SPE crystallinity decreased as nano-SiO2 concentration was increased. Mechanical analyses were conducted to characterize the SPE tensile strength and elongation at break. EIS analysis was conducted to measure SPE ionic conductivity. The PEO/NaClO4 SPE with the addition of 5% nano-SiO2 from sugarcane bagasse at 60 °C produced SPE with the highest ionic conductivity, 1.18 × 10−6 S/cm. It was concluded that the addition of nano-SiO2 increased ionic conductivity and interface stability at the solid polymer electrolyte-PEO/NaClO4.

Investigate the Thermal Analysis Properties of Polymer Electrolyte

Propylene carbonate (PC) (1:1) have been used as plasticizer to synthesized two series of polymer blend electrolytes (As and Cs) composed of Poly (methyl methacrylate) (PMMA)/Polyacrylonitrile (PAN), (80/20) Wt.% and ethylene carbonate (EC) using solution cast technique. Mixed iodide salts and varying weight ratio of potassium iodide (KI) and cesium iodide (CsI) was used to study the thermal properties of polymer blend electrolytes (GPEs). Differential Scanning Calorimeter (DSC) results show a decrease in the glass transition of electrolytes when increasing the weight percentage of salts, while the melting point increases due to the reduction in the polymer fluidity. Thermogravimetric analysis (TGA) indicates that the increase in the thermal stability can be attributed to the high thermal stability of polymer blend and the existence of the strong interaction between the two polymers. The optimum value of glass transition (Ts) is 104.2 °C found in sample containing 35 Wt.% of KI salt which has a melting point (Tm) 194.7 °C.

Comparison of Marginal Integrity and Surface Roughness of Selective Laser Melting, CAD-CAM and Digital Light Processing Manufactured Co-Cr Alloy Copings

The purpose of the present study was to evaluate the influence of fabrication techniques on the surface micro-roughness (Ra) and marginal misfit of cobalt chromium (CoCr) copings. A mandibular first molar was prepared for a metal ceramic crown. Forty metal copings were prepared and divided into groups (n = 10). Group 1, Casting-Lost wax technique (Cast-LWT), Group 2, CAD-CAM, Group 3, Selective laser melting (SLM), and Group 4, Digital light processing-Cast (DLP-Cast). Ra was measured using laser profilometry and marginal misfit was analyzed with Micro-CT. Analysis of variance (ANOVA), Tukey multiple comparison, and correlation coefficient tests were applied (p < 0.05). SLM technique showed the highest Ra (2.251 ± 0.310 μm) and the Cast-LWT group presented the lowest Ra (1.055 ± 0.184 μm). CAD-CAM copings showed statistically lower Ra compared with SLM samples (p = 0.028), but comparable Ra to DLP-Cast (p > 0.05). CoCr copings fabricated from the DLP-Cast technique demonstrated the highest marginal misfit (147.746 ± 30.306 μm) and the lowest misfit was established by SLM copings (27.193 ± 8.519 μm). The SLM technique displayed lower marginal misfit than DLP-Cast and CAD-CAM (p = 0.001), but comparable misfit to Cast-LWT copings. Ra influenced the marginal misfit in CAD-CAM, SLM, and DLP-Cast technique-fabricated copings. (p < 0.01). Marginal misfit and Ra of CoCr copings are contingent on the different fabrication techniques.

Thermal, Structural and Morphology Studies of PEO-LICF3SO3-DBP-ZrO2 Nanocomposite Polymer Electrolytes

This work represents thermal study of PEO-based polymer electrolyte films that were prepared by the solution cast technique. The melting temperature Tm, glass transition temperature Tg and degree of crystallinity χc were measured by diffraction scanning calorimetry (DSC). Thermogravimetric (TGA) was used to determine the initial and final degradation temperatures. The structural was also performed to characterize the vibrational wavelength and phase characteristic (crystalline/amorphous). While the morphological study was emphasized to examine the features appearance for pure polymer electrolyte system as well as after addition salt, plasticizer and filler. The zirconium oxide particles were measured after the milling process by using the transmission electron microscopy (TEM), and the particles obtained in the range of 9 – 54 nanometer size.

Morphometric study of human placenta and an insight into its vascular pattern by corrosion cast technique

: The placenta is a chorioallantoic, deciduate, haemochorial and villous organ. It is a vital organ which transfers vital nutrients from the mother to the foetus and removes waste products from the foetus to the mother. There has been paucity of literature regarding the morphometric study of human placenta and its vascular pattern (magisterial or dispersed) by corrosion cast technique. Therefore, the present study was conducted on morphometry and vascular pattern of the human placentae.: To do the morphological and morphometric study of placenta and to study the vascular pattern of placenta by corrosion cast technique. Study was done on 43 placentae and its morphometric study and vascular pattern were studied by corrosion cast technique.: Oval was the most common shape of placenta observed in the present study. Out of 43 placentae, 22(51.16%) had oval, 16(37.20%) placentae had round shape followed by triangular in 3(6.97%) placentae. Only 1 (2.32%) placenta each found to be irregular and multilobed. Most common shape recorded in complicated pregnancy was oval followed by round. Magisterial pattern was found in 13.95% of placenta and was associated with oval shape constituting 25.58% of placentae. Mixed pattern was seen in 18.60% placentae and was associated with oval placentae(23.25%). The disperse pattern was seen in 4.65% and was associated with oval and irregular placentae each constituting(2.32%).: The vascular cast preparation of placentae in our study will further help in contribution towards the understanding of the placental vasculature. An effort should be made for performing more studies on placentae of complicated pregnancies eg: hypertension and diabetes etc.

Physical and Electrical Studies of High Molecular Weight Poly (Methyl Methacrylate) Based Solid Polymer Electrolytes

In this work, the film contained a mixture of PMMA, salt, and plasticizers are studied. PMMA as a host polymer, ammonium trifluoromethane sulphonate or ammonium triflate (NH4CF3SO3) as a doping salt and ethylene carbonate (EC) as a plasticizer is used in this present study. PMMA salt complexes system and plasticized PMMA salt complexes system are prepared by solution cast technique at room temperature. FTIR is used to study the interaction between polymer and salt, and between polymer–salt and plasticizer. The carbonyl group C=O asymmetric stretching mode observed at 1721 cm-1 is broadened and shifted to lower wavenumber when ammonium triflate was added into PMMA. The broadening, shifting and reduction in wavenumbers of FTIR spectra show that the complexation has occurred between the polymer and salt. EIS is performed to measure the electrical conductivity of the polymer–salt system prepared at ambient temperature. The electrical conductivity of film containing 1.0 g of PMMA–35 wt% NH4CF3SO3–16 wt% EC exhibit the highest electrical conductivity with the value of 2.461 x 10-4 S/cm2. XRD is carried out to study the pattern of pure PMMA, PMMA–NH4CF3SO3 and PMMA–NH4CF3SO3–EC. The XRD analysis shows the addition of plasticizer to the polymer–salt system increase the amorphousness of the polymer electrolytes hence increases in conductivity.

A novel WC–W2C composite synthesis by arc plasma melt cast technique: microstructural and mechanical studies

WC–W2C composites of three different compositions have been synthesized from mixture of WC + W (0, 5 and 16 wt% W) by thermal arc plasma melt-cast technique. Various grown phases observed in the composites consisting of major phases of WC and W2C and minor phases of unbound C (graphite) and tungsten (W) were confirmed by X-ray diffraction, selected area electron diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared studies. Transmission electron microscopy and field emission scanning electron microscopy show polycrystalline nature of composites. Energy dispersive spectroscopy (of X-ray) infers the absence of any impurity in the composite. Almost porous free nature of composites were observed from X-ray micro computed tomography and BET analysis studies. WC–W2C composite (16 wt% W) shows 25% and 21% higher micro hardness (2535 VHN) and Young’s modulus (625 GPa) values than that of pure melt cast WC sample.