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Mechanical properties of six different binary ionic porphyrin crystals with variable morphologies were measured and correlated with their structural properties. These solids were formed from stoichiometric combinations of negatively charged tectons, meso-tetra(4-sulfonatophenyl) porphyrin (TSPP), Cu(II) meso-tetra(4-sulfonatophenyl)porphyrin (CuTSPP), Ni(II) meso-tetra (4-sulfonatophenyl)porphyrin (NiTSPP), and four different cationic tectons, namely, meso-tetra (4-pyridyl)porphyrin (TPyP), tetra(N-methyl-4-pyridyl)porphyrin (TMPyP), Cu(II) meso-tetra(Nmethyl- 4-pyridyl)porphyrin (CuTMPyP), Ni(II) meso-tetra(N-methyl-4-pyridyl)porphyrin (NiTMPyP), and tetra(4-aminophenyl)porphyrin (TAPP). Crystal structures were determined from single crystal and powder X-ray diffraction patterns. Scanning electron and atomic force microscopes (SEM and AFM) provided topographical information. The common arrangement of the porphyrin tectons within the crystals is consistent with alternating face-to-face molecular arrangement forming coherent columns along the fast-growing long axis which are held together by electrostatic and π–π interactions as well as hydrogen bonding. In acquiring the indentation data of the porphyrin crystals using AFM, stress was applied perpendicular to the direction where ionic and π–π bonds dominate the packing. At indent loads ≤50 nN/nm², all the porphyrin structures deformed elastically. Young’s modulus (E) values for the different crystals range from 6 to 28 GPa. In a broader perspective, this study highlights the extraordinary mechanical behavior of porphyrin assemblies formed by ionic self-assembly. Judicious selection of charged porphyrin synthons can yield crystalline materials with mechanical properties that combine the elastic characteristics of ‘soft’ polymers with the stiffness of composite materials. Such high-performance materials are excellent candidates for deformable optoelectronic devices.

Various modifier to former (m/f) ratios of 60%AgI - m%Ag₂O - f% (0.7TeO₂ + 0.3 P₂O₅), silver phosphotellurite [SPT] glasses were prepared by melt quench technique. The prepared samples were characterized by XRD, FTIR and DSC technique to find out respectively the glassy nature, structure and glass transition temperature (T_g). Complex impedance measurement were made for the SPT sample pellets in the frequency range from 40 Hz to 100 kHz and the impedance data were analyzed using the Boukamp equivalent circuit software. The best conductivity data is obtained from the conductivity results and its variation with m/f ratios 60%AgI - 28.57%Ag₂O - 11.43% (0.7TeO₂ + 0.3 P₂O₅) was explained using weak electrolyte model.

A new compound with a chemical formula SrTi₂Zn₂Fe₁₀O₂₂ has been synthesized using analar grade reactants by solid-state diffusion technique at 1173°K for 100 hour. The formation of the compound is checked by X-ray diffractometry with filtered Cu radiation. The structural result shows that the compound is in a single hexagonal phase without traces of unreacting phases of the reactants. The observed unit cell dimensions are a = 5.891 Å and c = 46.064 Å. The compound is studied magnetically by using Gouy’s balance and the result shows that it is ferrimagnetic at room temperature (Curie temperature T_C=334°K). From the paramagnetic behaviour of the compound above the critical temperature, Curie molar constant is worked out and is found to be 42.67, matching with the expected value for stable oxygen states of the cations in the molecule. Electrical conductivity measurement shows slight deviation from linearity near Curie temperature with activation energy 0.44 eV. In addition to these, the compound is analyzed by thermo-gravimetry, scanning electron microscopy and infrared absorption. The thermo-gravimetric analysis shows the compound is thermally stable upto 1273°K; the microstructural study (SEM) shows clearly hexagonal platelets with average particle size 2.263 μm where as the infrared absorption gives two absorption peaks as observed in spinel structures in the range 400 cm⁻¹ to 4600 cm⁻¹, which may be due to octahedral and tetrahedral complexes present in the compound.

This paper presents the growth and characterization of ZnO piezoelectric thin film using magnetron sputtering technology. In this paper, we studied the influence of annealing process and different substrates, including silicon, aluminum layer and silicon nitride thin film on silicon, on the piezoelectric performance of ZnO thin film by using XRD and SEM to analyze C-axis orientation and crystalline quality of ZnO thin film. In the end, we develop a fabrication process, for which the aluminum is still used as the bottom electrode but isolated from the ZnO thin film by a layer of silicon nitride thin film, to meet the requirements of the quality of the ZnO thin film growth and the compatibility with CMOS technology.

LiNiPO₄ and LiCoPO₄ cathode materials based on Phospho-Olivine structure have been prepared by Pechini – type Polymerizable Technique. Structural and thermal analyses have been done using XRD and TGA/DTA respectively. Formation of nano sized particles has been confirmed from the XRD analysis for both the samples. Conductivity analysis shows the conductivity in the order of ∼ 10⁻⁵Scm⁻¹ for both LiNiPO₄ and LiCoPO₄ at 303K. Transport parameter such as hopping frequency has been calculated from the conductance spectra.

Due to lack of good proton conductive polymer electrolyte working at ambient temperatures, search for the new systems have been hotly pursued in the past few years. Hence an attempt has been made to synthesis PVA based polymer electrolyte with various compositions of ammonium nitrate using solution casting technique. The formation of the complex has been confirmed by FT-IR spectral studies and XRD analysis. In the impedance response curve, the absence of the high frequency semicircular portion leads to the conclusion that the current carriers are ions & therefore the total conductivity is mainly the result of ion conduction. The high ionic conductivity at ambient temperature is found to be 7.5×10⁻³Scm⁻¹ for 20mol% ammonium nitrate doped PVA. Dielectric behaviour is analyzed using dielectric constant(ɛ') and dielectric loss (ɛ") of the samples .The low frequency dispersion of the dielectric constant implies the space charge effects arising from the electrodes. The dielectric loss spectra show the very large (~10⁶) dielectric loss at lower frequencies due to free charge motion within the material.

This paper was carried out to observe the effect of milling time on the particles and microstructure millscale-derrived BaFe₁₂O₁₉. The millscale was dry milled for 16h/20h/24h and sieve (45 μm) to obtain fine powder particles. The magnetic and nonmagnetic particles separation was done and oxidized FeO was obtained at 400°C/500°C/600°C for 10 hours in air. The Fe₂O₃ from the oxidation was crushed for 16h/20h/24h and was using as a raw material in BaFe₁₂O₁₉ fabrication. The mixture was calcine at 950°C for 10 hours in air. The calcine powder was again crushed for 16h/20h/24h to find a fine size particles. The development of stoichiometric Fe₂O₃ was confirmed by XRD result. The existence of submicron powder particle size was confirmed by a Malvern Particle-size Analyser Model No. MSS33544/785. A fine-grained and single-phase polycrystalline microstructure was confirmed to exist by SEM surface scan. The high remanence 2000Oe, 2000Oe saturation magnetisation and 1500Oe coercive force of sample derived from millscale was achieved. The effect of prolonged milling time showed a positive tendency for the formation of rectangular shape crytallites. This is due to the increased homogeneity of the starting mixtures which enhanced the solid state reaction.

Amine modified carbon quantum dots was synthesized by the acid oxidation method and hydrothermal route from coal in Barkol coalmine area and amine water. The features and properties of the product were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Photoluminescence Spectra (PL), UV-visible Spectroscopy (UV/vis), Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD). The results indicated that the GQDs have bright aquamarine with high water solubility, good photostability.

The formation of kidney stones was related closely to the properties of urinary crystallites. This study aims to investigate the components of urinary crystallites in 109 cases of patients with uric acid (UA) stones using High-Resolution Transmission Electron Microscopy (HRTEM). Urinary crystallites in patients with UA stones, that contain calcium oxalate monohydrate, calcium phosphate, and ammonium urate crystals, were detected and confirmed by X-ray Diffraction (XRD) and Fast Fourier transformation (FFT) in HRTEM, even in small quantities, showing the presence of high UA concentration and low pH in urine.

NiZnO thin films were grown on c-plane sapphire substrates by photo-catalysis metal organic chemical vapor deposition system. The samples with the different catalysis intensity were grown and the effects of catalysis intensity on the crystal, optical properties and surface morphology of the NiZnO films were researched. With the raising catalysis intensity, it can be found that the grain size of samples increased and thecrystal and optical properties improved remarkably. The main reason was the photon energy can provided the chemical processing higher activation energies and diffusion ability, whichwas benefit for atomic rearrangement to decrease the defect density. The photocatalysis had an important effect in the films oxidation process by MOCVD.

Proton conducting polymer electrolytes based on Poly (N-vinyl pyrrrolidone) and Ammmonium Bromide (NH₄Br) have been prepared in different compositions by solution casting technique. The prepared polymer electrolytes have been characterised by the experimental techniques such as XRD, DSC, AC Impedance Spectroscopy and ¹H NMR. The XRD analysis reveals the amorphous nature of the polymer electrolyte. The DSC analysis shows that the glass transition temperature of the polymer complexes decreases upon addition of NH₄Br salt indicating the interaction between the polymer and the salt. AC impedance analysis has been carried out to find the best composition possessing good electrical and mechanical stability. The maximum protonic conductivity at room temperature has been found to be 1.06×10⁻³Scm⁻¹ for 25 mol% salt doped electrolyte and the electrolyte obeys the Arrhenius behaviour. ¹HNMR study has been carried out on the prepared polymer electrolytes to have a better understanding of the ion transport mechanism. ¹HNMR study indicates that the NH₄⁺ ion is responsible for the proton conduction.

Composite polymer electrolytes have been prepared using Poly (vinyl alcohol), ammonium fluoride, nanofiller ZrO2 by solution casting technique. The amorphous nature of the composite polymer electrolyte has been confirmed by XRD analysis. FTIR analysis confirms the complex formation among the polymer, salt and nanofiller. The maximum ionic conductivity for 85 PVA:15 NH₄F has been found to be 6.9 × 10⁻⁶ Scm⁻¹ at ambient temperature. In the present work, the addition of 2 mol% nanofilller ZrO₂ to the electrolyte 85PVA:15NH₄F enhances the conductivity to 3.4 × 10⁻⁵Scm⁻¹. The temperature dependence of the conductivity of composite polymer electrolytes obeys Arrhenius relation. In the modulus spectra, there is a long tail at low frequencies which is an evidence for large capacitance associated with the electrodes. In the high frequency region, ∈'(ω) value saturates and giving rise to the dielectric constant of the material.

The main reasons for corrosion failure of pipeline in sour gas field have been proposed based on the analysis techniques of Optical Microscopy (OM), Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) and X-ray Diffraction (XRD). The results show that the leakage happened caused by pit corrosion in the test samples. Pit corrosion occurs under the condition of wet H₂S corrosion, while fouling and Cl^- do promotion. Test pipe material properties meet the conditions requirements of China. According to the condition of pipeline corrosion, it is suggested that the raw gas should process gas-water separation before transportation, and the filter unit should be added to reduce the sand and gravel content.