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Calcium magnesium carbonate, also known as dolomite, is dispersed throughout Florida as a constituent of phosphate-mined resources. The mineral is problematic in the phosphoric acid production of phosphate for agriculture and must be separated so that it does not negatively affect the process. This means that this natural resource has no beneficial end use. In the present study, we characterize high-concentration dolomite phosphatic pebbles from the Florida Industrial and Phosphate Research Institute and examined their feasibility for thermochemical energy storage at high temperatures. The dolomite mineral composition was studied prior to and after calcination (decarbonation) using scanning electron microscopy with energy-dispersive X-ray spectroscopy, powder X-ray diffraction, Fourier Transform Infrared Spectroscopy, and thermogravimetric analysis. The local samples were compared to a commercial dolomite sample and results confirm a high percentage of dolomite in the central Florida samples. Thermogravimetric analysis and powder X-ray diffraction indicated that the dolomite calcination is not fully complete at lower temperature, and at least 700 °C heat is required for the release of CO2 from the dolomite pebbles. Overall, the results show that the waste dolomite phosphatic pebbles are suitable for potential use in high-temperature thermochemical energy storage with long-term reversibility and cyclability.

This study is mainly focused on the fabrication of SiO2 as an inorganic shell material encapsulated an organic thermochromic (TC) core material comprises of either the (i) three-component as-synthesized blue dyes [BDTCM@SiO2] or (ii) off-the-shelf (commercial) black dyes [CDTCM@SiO2]. Both the SiO2 encapsulated thermochromic systems have successfully demonstrated the color transition at around 31 °C. For the three-component thermochromic microcapsules, we have used the crystal violet lactone (CVL) as a leuco dye, bisphenol-A (BPA) as a color developer, and 1-tetradecanol (TD) as a solvent. Different ratios of the thermochromic dye and the metal oxide were prepared to examine the effect of the core@shell ratio on the microstructural and thermal properties of the encapsulated microcapsules. The mean particles sizes of the BDTCM@SiO2 are below 100 nm, whereas, the CDTCM@SiO2 samples exhibited the mean particle sizes varied in a range of 100-1000 nm. The endothermic phase transition due to melting and in general, the thermal stabilities of these SiO2 encapsulated TCMs have been explored for the purpose of deploying these systems for thermal energy savings or storage applications.

Electrospinning is an inexpensive and versatile technique for fabricating micro- and nano- scaled fibers. There have been limited attempts to employ it for the fabrication of thermochromic (TC) fibers, and the fabrication of a three-component (dye, developer, and solvent) TC material has required the use of a more complicated coaxial electrospinning technique. Herein, a simple and novel method for creating thermochromic fibers by electrospinning single strands of poly (methyl methacrylate) (PMMA) with embedded thermochromic powder of a polymer encapsulated three-component system was employed. Unlike past leuco dye-based thermochromic fibers, an unmodified syringe tip can be used for the spinning process and only one flow rate needs to be determined. A solution of solvent (either N-dimethylformamide or chloroform), PMMA, and a commercially available black thermochromic powder was prepared and spun using a custom-made electrospinning apparatus. The spun fibers exhibited a clear color transition from grey to white and had average diameters of 2.53 µm and 1.96 µm for chloroform and N-dimethylformamide based fibers, respectively. The fibers were characterized by scanning electron and optical microscopy to determine their morphology, Fourier transform infrared spectroscopy to determine their chemical composition, and differential scanning calorimetry and thermogravimetric analysis to characterize their thermal properties.

In this present study, pure and Ni2+ (3, 7, and 10% mol.)-substituted SnO2 nanoparticles (NPs) were synthesized by sol-gel method. The prepared samples were characterized by powder XRD, FT-IR, FE-SEM, HR-TEM, EDX, UV-visible spectra, room temperature (RT) photoluminescence (PL) spectroscopy, and VSM techniques. XRD study revealed the polycrystalline tetragonal rutile structure of pure and Ni2+-substituted SnO2 NPs. Crystallite size of pure and Ni2+-substituted SnO2 NPs were found to be 26 to 34 nm in range. FT-IR study confirmed the presence of metal-oxide (M-O) bond vibrations for pure and Ni-substituted SnO2 NPs. FE-SEM, EDX, HR-TEM, and SAED pattern indicated that pure and Ni2+-substituted SnO2 NPs are well-defined formation of spherical-sized nanocrystallites, with diameter of about 10–40 nm of grain size. UV-Vis spectrum specified a sharp absorption peak ~ 425 nm representing the band to band transition. RT-PL study showed the peak ~ 467 nm for all samples, indicating the band gap of 2.65 eV. The higher value of Ms is found to be 0.0429 emu/g for Ni-substituted SnO2 NPs. Magnetic study revealed that the Ni-substituted SnO2 NPs presented ferromagnetism. Photocatalytic degradation (PCD) of methylene blue (MB) was analyzed using photo-catalytic reactor and obtained the maximum of PCD efficiency of 3% Ni-substituted SnO2 NPs under the visible light irradiation.

In the present work, a quantum chemical approach is followed to study the molecular geometry, vibrational spectra, thermodynamic and molecular electrostatic potential of the title compound. Experimental techniques of FTIR, FT-Raman and UV–Visible were used to study the vibrational and electronic spectrum. The complete vibrational band assignment has been made on the basis of PED distribution and the values are proposed. The thermodynamic properties were calculated at different temperatures and corresponding relations between the properties and temperature were also studied. The antibacterial activity of the title compound was examined against E. coli and other gram positive and gram negative bacteria’s by micro dilution method.

SnO2 nanoparticles @ carbon nanoparticles (SnO2@carbon NPs) were synthesized by a facile route using SnCl2·2H2O and filter paper as precursors for lithium ion battery. The different sized nanoparticles of SnO2@carbon NPs were prepared at different temperatures (400, 450 and 500 °C). From the powder X-ray diffraction study the various size of prepared nanoparticles at different temperatures were found to be 16.5 nm (400 °C), 28.5 nm (450 °C), and 35.6 nm (500 °C). Scanning electron microscope (SEM) study reveals the particle nature of synthesized SnO2@carbon NPs. The presence of individual constituents such as Sn, O and C was confirmed by EDAX analysis. TG/DTA studies give assurance of the presence of carbon nanoparticles. FT-Raman spectral study also confirmed the phase and structure of SnO2 nanoparticles. The band gaps of SnO2@carbon NPs prepared at different temperatures (400, 450 and 500) were found to be 3.64 eV, 3.39 eV, and 3.17 eV, respectively by a UV–Vis spectral study. The capacity of SnO2@ carbon NPs prepared at 500 °C was found to be showing better electrochemical properties.

The studies of composite materials are widely encouraged by various engineering product developers due to its enhanced compatibility and physical properties. This course of study deals with a new combination of sisal fiber reinforcement with IPN (Interpenetrating Polymer Networks) resins. The mechanical behaviour of sisal and IPN resins laminates are observed and studied in this experiment. Various proportions of sisal fiber in corporations were carried out such as 10%, 20%, 30%, 40%, 50%. These laminate structures were experimentally tested under tensile testing, impact testing and flexural testing. The micro structural behaviour of the laminates structures were viewed using scanning electron microscope. The entire results obtained by using experimentation were cross verified using ANSYS software. Finally the results of both experimental and finite element method using ANSYS software were found to be in good co-relation.

Deformation-induced grain-growth in nanocrystalline materials is a widely-reported phenomenon that has been attributed to grain boundary (GB) processes. In this paper, we report on the opposite phenomenon, wherein a stable nanocrystalline (NC) Cu-Ta alloy undergoes a further refinement of the nano-grains during severe plastic deformation (SPD). SPD up to 250% results in a significant grain-size reduction despite the 350°C increase in temperature caused by the deformation process. Experiments and atomistic-simulations show that this unexpected grain-refinement is a direct result of well-dispersed Ta-nanoclusters throughout grain centers and along GBs acting as kinetic-pinning agents and suppressing GB processes that occur during recrystallization.

The Identification of new polymeric fibers is in high demand owing to its versatile applications. In this work the Lightweight foamed concrete (LFC) concrete is selected as a key ingredients and it is blended uniformly. In this work various mechanical properties were examined by incorporating newly modified polypropylene fibers, it is biaxial oriented in its structure.4:1 ratio of sand proportion is maintained. Newly modified PP fibers with percentages of 0.30% and 0.40% were added. The foamed concrete was intended to accomplish the consequence of impact from volume newly modified polypropylene fiber utilized with various relieving ages. The examination was setup to look at its mechanical properties with agreement to ASTM standard strategy for testing. From the outcome broke down, the consideration of polypropylene fiber into the lightweight foamed concrete examples has more commitment in flexural quality when contrasted with control test without the fiber. The 0.30% and 0.40% level of polypropylene fibers added is demonstrated to have contributed more on flexural of LFC. Based on the results it was concluded that the 0.30% is an ideal volume of fibers that ought to be incorporated to contribute the greatest flexural quality of the lightweight foamed concrete.

Thermomechanical behavior of an ultrafine-grained nickel-yttrium alloy has been investigated through quasi-static (10−4 s−1) and high temperature creep experiments under uniaxial compression along with post-deformed transmission electron microscopy (TEM) characterization. While the alloy possesses a quasi-static flow stress of ~1255 MPa at room temperature, the flow stress drops by about 80% at 873 K. TEM analysis showed negligible average grain growth over the entire temperature range tested. Furthermore, the alloy showed exceptional steady–state creep behavior owing to the relative stability of the grain size and interactions between dislocations/grain boundary and inclusions/dispersoids.

Nanocrystalline (NC) materials possess excellent room temperature properties, such as high strength, wear resistance, and toughness as compared to their coarse-grained counterparts. However, due to the excess free energy, NC microstructures are unstable at higher temperatures. Significant grain growth is observed already at moderately low temperatures, limiting the broader applicability of NC materials. Here, we present a design approach that leads to a significant improvement in the high temperature tensile creep resistance (up to 0.64 of the melting temperature) of a NC Cu-Ta alloy. The design approach involves alloying of pure elements to create a distribution of nanometer sized solute clusters within the grains and along the grain boundaries. We demonstrate that the addition of Ta nanoclusters inhibits the migration of grain boundaries at high temperatures and reduces the dislocation motion. This leads to a highly unusual tensile creep behavior, including the absence of any appreciable steady-state creep deformation normally observed in almost all materials. This design strategy can be readily scaled-up for bulk manufacturing of creep-resistant NC parts and transferred to other multicomponent systems such as Ni-based alloys.

Nanocrystalline materials are known to possess excellent radiation resistance due to high fraction of grain boundaries that act as defect sinks, provided they are microstructurally stable at such extreme conditions. In this work, radiation response of a stable nanocrystalline Cu-Ta alloy is studied by irradiating with 4 MeV copper ions to doses (close to the surface) of 1 displacements per atom (dpa) at room temperature (RT); 10 dpa at RT, 573 and 723 K; 100 and 200 dpa at RT and 573 K. Nanoindentation results carried out for samples irradiated till 100 dpa at RT and 573 K show exceptionally low radiation hardening behavior compared to various candidate materials from literature. Results from microstructural characterization, using atom probe analysis and transmission electron microscopy, show a stable nanocrystalline microstructure with minimal grain growth and a meagre swelling in samples irradiated to 100 dpa (~0.2%) and 200 dpa at RT, while no voids in those at 573 K. This radiation tolerance is partly attributed to the stability of Ta nanoclusters due to phase separating nature of the alloy. Additionally, the larger tantalum particles are observed to undergo ballistic dissolution at doses greater than 100 dpa and are eventually precipitated as nanoclusters, replenishing the sink strength, which enhanced material's radiation tolerance when exposed to high irradiation doses and elevated temperatures.

Ferrite-Ferroelectric composites with the generic formula y(Mn0.5Cu0.5Fe2O4)1 − y[Ca0.1Ba0.9Zr0.1Ti0.9] (y = 25%, 50% and 75%) are prepared by solid-state reaction. One of the prepared samples of the composites 25%Mn0.5Cu0.5Fe2O4–75%Ca0.1Ba0.9Zr0.1Ti0.9O3 (MCF-CBZT) is subjected to high-energy mechanical milling for different durations (12 h, 18 h and 30 h). The compositional stoichiometry of all the samples is checked by Energy Dispersive Spectroscopy. All the un-milled and milled samples are characterized by X-ray diffraction, scanning electron microscopy, FTIR, magnetometry, and dielectric and magnetoelectric coefficient measurements. Magnetoelectric composite possesses biphasic surrounding to exhibit complex behavior of ME effect. The present study reveals influence of mechanical milling on MCF-CBZT magnetoelectric composite. The XRD confirms the presence of ferrite and ferroelectric phases for all the samples and microstructural changes appear in SEM images of milled specimens. FTIR spectra show four characteristic bands in 400–800 cm−1 range. Saturation magnetization and Curie temperature decrease as milling duration increases. Relaxed broad doublet with the distribution of nuclear hyperfine fields is found in Mossbauer spectra indicating good coupling between ferrite-ferroelectric phases caused by mechanical milling for the multiferroic composite. The frequency response of dielectric constant and loss tangent is recorded in the frequency range from 100 Hz to 1 MHz. The static value of magnetoelectric factor has been studied as a function of magnetic field for un-milled and milled MCF-CBZT samples. The maximum value 382 μV/cm·Oe of (ME)H is observed for the 18 h milled MCF-CBZT sample.

The CdO/CeO2 and CdO/CeO2/PVP nanocomposites were synthesized by microwave irradiation. The X-ray diffraction study confirms that CdO/CeO2 and CdO/CeO2/PVP nanocomposites are polycrystalline nature with cubic structure. The particle size of heterostructure CdO/CeO2 and CdO/CeO2/PVP nanocomposites is decreased when compared with pure CdO. The energy-dispersive X-ray spectra confirm the existence of elements such as Cd, O, and Ce. FTIR analyzes the successful formation of the heterostructured CdO/CeO2 nanocomposites. Morphological analysis confirms that the addition of PVP is reducing the particle size from agglomerated. UV-vis spectra corroborate the incorporation of CeO2 particles on the surface of CdO. The CdO/CeO2 and CdO/CeO2/PVP nanocomposites have an increase in bandgap value compared with CdO due to quantum confinement effect. Photoluminescence spectra confirmed that the existence of defects and efficient charge separation of CeO2–CdO in CdO/CeO2 and CdO/CeO2/PVP samples are due to the reduction in particle size. The prepared CdO/CeO2 and CdO/CeO2/PVP nanocomposites show the enhanced photocatalytic activity in methylene blue (MB) dye under UV irradiation. Magnetic measurement results show the room temperature ferromagnetism in all synthesized samples due to the existence of defects and quantum confinement effect. The observed results reveal that both CeO2 and PVP produce considerable changes in the physical properties of CdO.

A new brucinium 4-methyl-3-nitrobenzoate 0.5 hydrate (B4M3NB0.5H) NLO single crystal was harvested from saturated solution by solvent evaporation method. Crystal system and symmetric type of B4M3NB0.5H compound were analyzed by structure analysis. Linear optical parameters of title compound were discussed in detail by UV–visible analysis. Lifetime values of the molecule were quantified by fluorescence study, and it confirms the good crystalline perfection of the grown crystal. The SHG efficiency is 5.11 times superior to the KDP material. By utilizing Nd:YAG laser as an input, SLDT measurement of the crystal was done. The grown crystal has good crystalline nature which is analyzed by HRXRD study. Dielectric behavior of B4M3NB0.5H crystal was discussed in detail. With the help of theoretical approach, few of the solid-state parameters were calculated and listed. Piezoelectric charge coefficient and piezovoltage were calculated to be 4.5 p C/N and 0.0417 p V m/N, respectively. The TGA and DTA spectrum confirms that the title compound is thermally stable up to 101 °C.

An investigation has been performed on the slurry erosion behavior of squeeze cast AA7150 aluminium alloy – a potential structural alloy in as cast condition. The tests were conducted at room temperature varying the service factors using quarts silica sand. The cast samples were examined for its metallurgical and mechanical factors followed by investigation on erosive wear behavior. The results showed the ductile nature of mechanism undergone and greater influence was seen with respect to the angle of impingement. The erodent flow rate also significantly affects the performance of the material. The surface morphologies of the wear tested specimens were examined using SEM for better understanding on the mechanism of failure. Severe plastic deformation is seen in all the cases as the strain energy exceeded the elastic strain rate.

The functionally graded material (FGM) is referred as the material which is non-uniform and has changing structure and material composition. FGMs are now being used in different types of areas that are different from the initial area of application. A functional gradient porous structure is designed and modelled as prototype to validate for the mechanical and biomedical applications. In this work, gradient porous structure of Gyroid shape is used to design a model. Gradient porous structure is entirely different from the homogenous porous structure but like homogenous porous structure, it reduces material consumption with maintenance of similar strength. To fabricate the model, stainless steel 316L is used, which is a biomaterial. The effect of functional gradient on the compressive strength of the structures by considering nine different porosities (porosities = 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%) both experimentally and numerically, is studied. The initial stage involved the development of mathematical model of functionally gradient porous structure based on governing equation of Gyroid, which is a triply periodic minimal surface. CAD models of normal porous and gradient porous structures are generated using K3DSurf and Rhinoceros software. Developed structures are manufactured by Direct Metal Laser Sintering (DMLS) Additive manufacturing method with stainless steel 316L as the build material and experimentally tested under quasi static compressive loading conditions. These models are analyzed in ANSYS software. The CAD model is validated by comparing the experimental and numerical results and the Deviation between yield stress from experimental and numerical results obtained was 3.5%.

Thermal power plant will continue to cater to the power demand of India at least for two more decades. Research is going on continuously to increase the temperature of operation of the materials used in power plant to increase the operating efficiency, conserve the fuel and reduce the environmental impact of power generation. Superheater coils made of nickel based alloys have an advantage over conventionally used materials like AISI 316, P91, P92 in powerplants. In the present work, an attempt is made to understand the creep related life of nickel based superalloy, Alloy 617 material in India powerplants. Alloy 617 can be a potential material for an ultra-super critical powerplant as it is known to withstand temperatures of around 700 °C and supercritical pressure upto 300 bar. These parameters significantly higher than the present operating values of 600 °C and 250 bar pressure in a typical Indian scenario. Extensive literature survey was carried out to understand the existing creep models, the thermophysical properties and parameters for evaluating Larson-Miller Parameter (LMP). Heat transfer simulation was carried out using ANSYS to predict the temperature field and the hoop stresses induced in the final stage of super heater coil exposed to the severest operating conditions in the power boiler, was predicted based on the boiler operating pressure in the ultra-super critical region. Formation and growth of oxide scale was not considered in the present model as literature suggests that the rate of oxide formation is negligible for the present material at 700 °C. Hoop stress and temperature distribution were used to predict the total life by applying Larson Miller Parameter approach. Robinson’s damage summation rule was attempted to determine the creep life of the material for the above conditions. Based on the analysis, it is observed that Alloy 617 can be the most suitable material for final stage superheater coil operating at around 700 °C.

A significantly large amount of thermal energy is lost from or gained in buildings as a result of solar radiation. A comfortable temperature can be maintained by correctly designing and arranging a building’s windows and smart roof coatings. Single layer or multilayer thin film coatings, with spectrally desirable characteristics, are deposited on glass or roof surfaces and can greatly improve a building’s energy efficiency. Thermochromic materials present some advantages due to their reversible color and phase change behavior near ambient temperature. For example, a thermochromic coating on a roof’s surface can change color (black to white) reversibly when heated at around 30 °C, reflecting solar radiation and reducing a building’s cooling needs. In the present study, various thermochromic coatings on glass slides are investigated. In this work, the effect of non-toxic titanium dioxide (TiO2), used as a UV radiation protective coating on thermochromic particles (such as a three-component blue dye synthesized in the lab or a commercially available black dye), is discussed. The composite coatings of the chosen components can reduce a building’s cooling and heating energy needs and provide an environmentally sustainable solution for a green economy. Several physico-chemical characterization techniques were used to understand the surface, interfacial, spectroscopic, and thermal behavior of TiO2 or SiO2 coatings and phase change thermochromic materials for applications in thermal storage and enhanced energy efficiency.

In this research study, the PVP capped CdO/SnO2, hybrid CdO/SnO2, and pure CdO nanocomposites were synthesized using simple chemical reaction and microwave irradiation method. The semantic approach studies the structural, morphological, elemental composition, optical, magnetic, thermal properties. XRD studies confirm that the particle size decreased in PVP capped CdO/SnO2 and CdO/SnO2 nanocomposites compared to pure CdO sample. Also, the existence of diffraction peaks of both CdO and SnO2 in fabricated hybrid CdO/SnO2 nanocomposite proves that the lattice combination of CdO and SnO2. The SEM and TEM images conclude that after doping of SnO2 and PVP with CdO nanoparticles, the particle structure transformed to rod-like morphology. FTIR spectrum of SnO2 and PVP: SnO2 doped CdO and their functional groups were studied. And also the presence of elemental composition analyzed by EDS spectrum. The UV absorption spectra results of SnO2 and PVP: SnO2 doped CdO states the red-shifted in the bandgap. An enhanced photocatalytic activity is observed in SnO2, PVP doped CdO nanocomposites. The thermal analysis curve of TGA and DTA confirms the thermal stability of synthesized nanocomposites. The CdO sample exhibits the ferromagnetic property. And Antiferromagnetism property is observed in SnO2, PVP doped CdO nanocomposites.

A tin oxide-carbon composite (SnOx-C) was fabricated as a candidate for use as an anode in lithium-ion batteries through the pyrolysis of a ditin citrate precursor. The simultaneous formation of ti...

This work investigates macroscopic plastic behavior in polycrystalline Ti with varying oxygen concentrations using both experiments and a crystal plasticity finite element framework applied to a representative volume element (RVE) of the microstructure. The proposed multiscale framework makes use of parameters such as critical resolved shear stress (CRSS) ratios obtained from lower length scale first-principle calculations and strain hardening rates obtained from experiments. Generalized stacking fault energy calculations (GSFE) in combination with the Peierls-Nabarro model and a temperature dependent phenomenological description of CRSS were utilized to compute the CRSS ratios for different slip systems in Ti with and without oxygen. Experimentally measured stress-strain responses along the rolling direction for polycrystalline Ti with different oxygen concentrations were used to obtain the strain hardening rates. The crystal plasticity framework was then calibrated using the computed CRSS ratios and the strain-hardening rate for Ti with various oxygen concentrations. The calibrated model was then used to predict the macroscopic response of Ti under different loading conditions and orientations with different oxygen concentrations. Without tuning the fitting parameters for the crystal plasticity framework, we show that the model is able to simulate the experimental responses within the experimental uncertainty. Thus, a systematic calibration procedure is presented to capture the macroscopic homogeneous responses of Ti with various oxygen concentrations.

The incorporation of Carbon in Tin Oxide (SnO2) nanocomposite (SnO2@C NCs) was synthesized successfully by hydrothermal method with sucrose and tin dichloride dihydrate (SnCl2.2H2O) as precursor materials and was sintered at different temperatures. The as prepared SnO2-Carbon nanocomposites were characterized by various techniques such as X-ray powder diffraction (XRD), Scanning electron microscopy (SEM) along with Energy dispersive X-ray (EDX), high resolution transmission electron microscopy (HR-TEM), Raman spectra, TGA and Electrochemical analyses. The controlled addition of Carbon in SnO2 to exhibit enhanced electrochemical property was also studied. It was demonstrated that the Carbon derived from sucrose assisted anode showed the high reversible capacity of about 581 mAhg-1 indicating that the possibility of further increment in Li storage property. The initial discharge capacities of the samples heat treated at 400 °C, 450 °C and 500 °C were 1424.79, 1061.71 and 531.28 mAh g-1, exhibiting an increasing trend in capacity with increasing the Carbon content. The columbic efficiency of SnO2@C NCs attains more than 95%. The electrodes show a long cycling ability and high charge and discharge capacity due to the presence of carbon.

In this present work, Tin Oxide-Carbon (SnO2–C) nanocomposite (NCs) was synthesized via annealing method using glucose and SnCl2 as precursors. As-prepared SnO2–C NCs were investigated by X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray (EDX) diffraction, Thermo-gravimetric analysis (TGA) and UV–visible spectral analyses. The electrochemical galvanostatic charge/discharge test shows that SnO2–C NCs possesses excellent electrochemical performance and enhanced cycling life. It exhibits a capacity of 180 mAh/g at the current density of 100 mAh/g and maintains the same capacity up to150 cycles. The observed efficient electrochemical property should have originated from the nanostructured carbon present in SnO2–C NCs, which in turn could have conferred the ability to accommodate the volume changes and prevented changes in Sn particle size during the charge/discharge process. It provides effective channels for lithium ion transport.

Nanostructured copper oxide thin films were deposited on soda lime glass substrates by reactive radio frequency (RF) magnetron sputtering using pure Cu target. The effect of oxygen (O2) partial pressure (5–50%) on physical properties of deposited films were investigated. The XRD analysis indicates the cubic structure of Cu2O changes to monoclinic CuO as a function of increasing O2 pressure. The Raman spectroscopy results further confirmed the phase variations of Cu based oxide films. Morphological analysis showed that the deposited films are highly uniform with nano gravels and agglomerated nano flake like structures for Cu2O and CuO thin films respectively. The surface roughness of the films decreases from 2.05 to 1.07 nm by increasing O2 pressure. X-ray photoelectron spectroscopy confirmed the binding energy variation in the oxidation state of the films. The optical band gap of deposited Cu2O is 2.12 eV, while that of CuO varies in the range of 1.79–1.82 eV. Hall effect measurement revealed that all the films exhibit p-type conductivity. The photocatalytic activity studies of as-deposited films have been carried out with different organic pollutants such as methylene blue, methyl orange and ciprofloxacin under solar irradiation. The Cu2O thin films exhibited higher degradation efficiency than CuO films under identical conditions. The mechanism of photocatalytic activity of copper oxide thin films is explained.

In the current work, tin oxide (SnO2) nanoparticles (NPs) are being synthesized by sol–gel method by varying reaction parameter such as ammonia feed rate. The synthesized NPs have also characterized by X-ray powder diffraction (XRD), high resolution scanning electron microscopy (HRSEM) and UV–visible spectroscopy. SnO2 nanofluid is being prepared by using of synthesized nanoparticles with the base fluid as water along with the help of sonication. The ultrasonic velocity and density values are being measured in five different concentrations of SnO2 nanofluids at different temperatures ranging from 298.15 K to 323.15 K.The thermal conductivity values were evaluated from the experimental data. The intermolecular interactions responsible for the changes in thermal conductivity with respect to the concentration and the temperature have also been conferred and the thermal conductivities of nanofluids were also calculated through the ultrasonic methodology and the results have also been compared with the flash laser method, derived experimentally.

Here, the Cottrell–Stokes ratio in a microstructurally-stable Cu-3Ta (at.%) nanocrystalline alloy is examined from the standpoint of changes in deformation mechanisms. Toward this, uniaxial compression experiments were performed in the temperature range of 113 K – 273 K. The Cottrell-Stokes ratio at the lowest temperature tested was ~1.3, and the material exhibited a very low strain-rate sensitivity at cryogenic-temperatures. Transmission electron microscopy (TEM) characterization showed negligible average grain size coarsening and a transition in the deformation mechanism toward athermal activation processes such as twinning with the reduction in the testing temperature.

Pure and dual doped ZnO nanoparticles were synthesized via the wet chemical method. The synthesized samples were characterized by XRD, HR-SEM/EDS, HR-TEM, UV–Vis, PL, FT-IR, and FT-Raman spectral measurements. The prepared ZnO nanoparticles exhibit a hexagonal wurtzite structure and [Ce–La, La–Gd, Gd–Ce] rare earth dual doped ZnO nanoparticles was confirmed from the shift in XRD peaks position, cell parameter and also changes in the peaks intensity. HR-SEM/EDS and HR-TEM show spherical in shape with less agglomeration on the surface of all samples and the images are clearly revealed that the particle size ~ 40 nm (PZ), 14 nm (ZCL3), 16 nm (ZLG3) and 28 nm (ZGC3). UV–Vis spectra show a strong Ultraviolet region absorbance for ZCL3 sample with the low Energy band gap value of 2.81 eV. The presences of the functional group and molecular vibrations are characterized by employing the FT-IR and FT-Raman spectra. From the PL spectra, it was found that the peak position of all samples produces a visible emission. The photocatalytic performance of the synthesized doped nanoparticles found to exhibit better degradation of MB dye under solar irradiation ZCL3 showed an increase in the photo catalytic decolorization efficiency. The bactericidal activity of dual doped ZnO nanoparticles was investigated against Gram-positive and Gram-negative bacteria and compare with standard ampicillin. We observe that ZCL3 sample have excellent antibacterial activity against Gram-negative bacteria (P. mirabilis) and the mean zone of inhibition ~ 20 mm.

We have investigated the complex metal hydrides involving light weight elements or compounds for the reversible hydrogen storage. The complex hydrides are prepared via an inexpensive solid state mechanochemical process under reactive atmosphere at ambient temperatures. The complex metal hydride, LiBH4 with different mole concentrations of ZnCl2 were characterized for the new phase formation and hydrogen decomposition characteristics of Zn(BH4)2. Furthermore, the complex metal hydride is destabilized using the addition of nano MgH2 for the reversible hydrogen storage characteristics. The structural, microstructural, surface, and other physicochemical behaviors of these lightweight complex metal hydrides have been studied via various metrological tools such as x-ray diffraction, Fourier transform infrared spectroscopy, thermal programed desorption, and PCT hydrogen absorption methods.

The pure CdO and CdO/La 2 O 3 , and CdO/La 2 O 3 /PVP nanocomposites were synthesized by microwave irradiation method. The prepared samples are analyzed by X-Ray diffraction (XRD), Fourier Transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), Transmission electron microscope (TEM), UV visible spectrometer, Photoluminescence (PL), and Vibrating sample magnetometer (VSM). XRD and FTIR studies confirmed the formation of binary metallic nanocomposites. SEM and TEM analysis authenticate that the addition of lanthanum oxide and PVP influences the size and morphology of CdO nanoparticles the bandgap value can be tuned by the addition of La 2 O 3 and PVP. Photoluminescence spectra show the violet emission in the region between 432 nm to 460 nm and the green emission peak at 529 nm for all three synthesized samples. CIE color coordinates for CdO and CdO/La 2 O 3 , and CdO/La 2 O 3 /PVP nanocomposites were also estimated from emission spectrum. The VSM results confirmed that the nanocomposites possess the weak ferromagnetic properties due to the inclusion of La 2 O 3 and PVP. The dielectric constant, electrical conductivity and dielectric loss values at room temperature have been analyzed for CdO and CdO/La 2 O 3 , and CdO/La 2 O 3 /PVP nanocomposites. Among the three synthesized samples, the CdO/La 2 O 3 /PVP nanocomposite attain high electromagnetic shielding efficiency. Furthermore, the rare earth element lanthanum oxide and PVP enhances the efficiency of photocatalytic degradation of MB dye.

Copper oxide nanoparticles (CuO NPs) were synthesized by a simple green method using Camellia sinensis (Tea) extract as a reducing agent. The CuO NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscope (FESEM) with energy dispersive X-ray spectroscopy (EDX), High resolution transmission electron microscope (HRTEM) and Selected area electron diffraction (SAED) techniques. The crystallite size estimated by Scherrer method was 35nm. The maximum absorbance of the CuO NPs was observed at 264 nm. The average particle size from HR-TEM was found to be 40-45nm. In this work we demonstrate the degradation of Malachite Green (MG) in aqueous solutions under sonocatalytic treatment. The dissimilarity of dye absorbance under UV-Vis spectrophotometer was used to calculate the degradation efficiency of CuO NPs. Moreover the kinetic process from the degradation result shows the MG dye follows the pseudo-first order kinetics.

Temperature is one of the most measured parameters within industry. Thermocouple is an extremely versatile device widely used in industry for critical high temperature, achieving extremely high accuracy with a thermocouple can be more difficult because of their inhomogeneity. Temperature drift in thermocouple is a common problem that affects the accuracy of a measurement system. Due to prolonged usage of thermocouple under different conditions causes changes in the properties of the thermocouple and in turn degrade the thermocouple which is followed by drift. Hence it is important to analyze the rate of degradation of the thermocouple material. In this work, material analysis using scanning electron microscopy by an energy dispersive X-ray (SEM-EDAX) has been performed on the thermocouple, due to change in temperature gradient at different insertion positions.

In this work, a nanocrystalline (NC) Cu-10at.%Ta alloy is irradiated with helium at different temperatures to assess the stability and effectiveness of Ta nanoclusters in trapping helium and suppressing swelling. Advanced microstructural characterization of the room-temperature irradiated specimens indicated the presence of small He-bubbles (∼1-2 nm) at the peak damage depth mainly at the core and along the interface of Ta nanoclusters with Cu matrix. Few bubbles were found along grain boundaries, with much smaller bubbles homogenously distributed within the copper lattice. High-temperature irradiation exhibited bubbles of ∼3-5 nm, which were primarily associated with nanoclusters as compared to other locations, with no observed faceting of the bubbles. Atom probe analysis confirmed helium partitioning to the Ta nanoclusters indicating the effective entrapment of these He atoms.

Nowadays many of the conventional materials are effectively replaced by composite materials, because of their light weight to stiffness ratio. Gears are the very essential components in mechanical power transmission, and drive in the most industrial rotating machinery. Polymer gears are used in motion and power transmission under different loads and speeds. Gears are generally made from metallic materials but recently advanced polymeric materials were developed because of low cost, light weight, high strength and improved performance of the system. Nylon, polymers, acetal and derlin are the structural polymeric materials used in printing and robotics, mechanical machines such as washing machines, sugarcane crushing machine and gear pump that are used for power and speed transmission. The paper investigates the polymer matrix composites gear with different fiber proportions. The main objective is to make glass fiber reinforced polymer gears using epoxy resin with various proportions of E-glass CSM (5%, 10%, 15%, 20%). The work investigates the wear testing of polymer gears of different proportions with metal gear using gear testing rig. The paper focused on morphology of fractured surfaces of polymer gears using scanning electron microscope. Finally, the gear is modeled in Catia software and imported to Ansys for static structural application.

In the field of energy storage, recently investigated nanocomposites show promise in terms of high hydrogen uptake and release with enhancement in the reaction kinetics. Among several, carbonaceous nanovariants like carbon nanotubes (CNTs), fullerenes, and graphitic nanofibers reveal reversible hydrogen sorption characteristics at 77 K, due to their van der Waals interaction. The spillover mechanism combining Pd nanoparticles on the host metal-organic framework (MOF) show room temperature uptake of hydrogen. Metal or complex hydrides either in the nanocomposite form and its subset, nanocatalyst dispersed alloy phases illustrate the concept of nanoengineering and nanoconfinement of particles with tailor-made properties for reversible hydrogen storage. Another class of materials comprising polymeric nanostructures such as conducting polyaniline and their functionalized nanocomposites are versatile hydrogen storage materials because of their unique size, high specific surface-area, pore-volume, and bulk properties. The salient features of nanocomposite materials for reversible hydrogen storage are reviewed and discussed.

Nanocrystalline materials possess excellent room temperature properties, such as high strength, wear resistance, and toughness as compared to their coarse-grained counterparts. However, due to excess free energy, nanocrystalline microstructures are unstable at higher temperatures. Significant grain growth is observed already at moderately low temperatures, limiting their broader applicability. Here, we present a design approach that leads to a significant improvement in the high temperature tensile creep resistance (up to 0.64 of the melting temperature Tm) of a nanocrystalline Cu-Ta alloy. The design approach involves alloying of pure elements for engineering nanometer sized solute clusters within the solvent grains as well as along the grain boundaries. Using a chemically optimized nanocrystalline Cu-3at.%Ta alloy as a model material system, we demonstrate that the addition of Ta nanoclusters inhibits the migration of the planar defects at higher temperatures and reduces the dislocation motion, leading to extraordinary high temperature properties. For instance, the NC Cu-3Ta alloy tested under tensile creep conditions up to the temperature of 873 K (0.64Tm) displays highly unusual behavior, including the absence of any appreciable steady-state creep deformation which is normally observed in almost all materials. This approach can be readily scaled-up for bulk manufacturing of creep resistant nanocrystalline parts. Moreover, this design strategy can be transferred to other multicomponent systems such as Ni-based alloys for making nanocrystalline materials with tailored properties.

A new and optically good transparent Brucinium Chlorate di-hydrate (BCDH) single crystal was grown from aqueous solution by the slow evaporation technique at a pH of 5 with dimension 11 × 4 × 2 mm3 over a period of 40–45 days. It belongs to the monoclinic crystal system with non-centrosymmetric space group C2 which is identified by single crystal XRD analysis. Percentage of carbon, hydrogen and oxygen are confirmed by chemical CHN analysis. The development faces were identified by morphological studies. The BCDH crystal possesses 78% transmittance which is confirmed by UV–Visible analysis. The presences of various functional groups were confirmed by vibrational analysis. Piezoelectric charge co-efficient (d33) of BCDH crystal was found to be 4 p C/N. The frequency doubling ability of title compound was analyzed using Kurtz and Perry powder method and its output were compared with standard materials. The LDT value of the BCDH crystal was found to be 3.51 GW/cm2. The electron excitation and life time measurements of the molecules in grown BCDH crystal was studied by Fluorescence spectral analysis. The stability and various decomposition stages of BCDH crystal were scrutinized by different thermal analysis.

Passive survivability of Commercially-off-the-shelf 18650 lithium-ion cells is tested in a thermal scenario similar to lunar night. Survivability of cells in particular and battery pack in general is crucial for resumption of function of any lunar exploration rover after hibernation at every lunar night. The test is designed to include a batch of Commercial lithium-ion cells from different manufacturers, with different nameplate capacities and different States of Charge. The cell behaviour during the test is monitored in-situ using cell terminal voltage measurements. To comprehend the effect of exposure to extreme low temperatures some complementary tests like visual examination, dimensional measurements, Residual Gas Analysis to detect any leakage, electrical tests to appraise electrical performance and 3 dimensional x-ray computed tomography analysis to view cell internal features are carried out at ambient conditions on cells both prior-to and after soaking at low temperatures. Results indicate successful survivability of tested cells after extreme thermal soak without any significant physical or internal damage or electrical performance degradation. Variation in cell terminal voltage with temperature is a reversible change attributed to the reversible phenomenon of freezing of cell electrolyte which furthermore is confirmed through ex-situ measurement of freezing point of electrolyte extracted from tested cells.

In the current work, pure zinc oxide (ZnO), cerium (Ce) doped ZnO, lanthanum (La) doped ZnO and cerium-lanthanum (Ce-La) doped ZnO nanoparticles (NPs) have been synthesized by the wet chemical method. The prepared samples have been dispersed into water and mixed thoroughly by the way of ultrasonication process to acquire nanofluid samples. The change of ultrasound velocity in aqueous solution was investigated as a function of particle size and suspension density. The thermal conductivity and acoustical parameters such as adiabatic compressibility, intermolecular free length and acoustic impedance have been evaluated from the experimental data. Also, the thermal conductivities of nanofluids have been calculated through ultrasonic method and the results were compared experimentally with the flash laser technique method. The thermal conductivities decrease with doping according to the rare earth atomic mass and ionic radius.

In this study, Octylamine (OA) capped zinc oxide (ZnO) nanoparticles were synthesized by the wet - chemical method. Zinc acetate dihydrate was used as precursor materials. The structural, morphological and optical properties were characterized by X-ray Diffraction (XRD), High resolution-Scanning electron microscope (HR-SEM), Energy dispersive X-ray (EDAX), UV–vis diffused reflectance spectroscopy (DRS) techniques respectively. The presence of ZnO was confirmed by FT-IR and FT-RAMAN spectroscopy analyses. Further, the photocatalytic degradation of Eosin Yellow (EY) known as textile dye was investigated from pure and OA-capped ZnO nanoparticles in de-ionized water under sunlight irradiation.

Nanofluids have been prepared by dispersing TiO2 nanoparticles in 70:30% (by weight) water–propylene glycol mixture. The thermal conductivity and viscosity were found experimentally at various temperatures with the volume concentrations 0.1–0.8%. The results indicate that the thermal conductivity of the nanofluids increases with the volume concentration and temperature. Similarly, the viscosity of the nanofluids increases with the volume concentration but decreases with increase in the temperature. Correlations have been proposed for estimating the thermal conductivity and viscosity of the nanofluids. The potential heat transfer benefits of their use in laminar and turbulent flow conditions has been explained.

Continuous Solar irradiation on the photovoltaic panel causes its temperature to increase, resulting in reduced efficiency. The present paper focuses on improving the efficiency of the photovoltaic panel through the use of hybrid Photovoltaic-Thermal (PVT) system. Water is used as the coolant in the cooling channel, flowing through the copper tubing provided below the photovoltaic panel, where the temperature is maximum. The thermal energy extracted in the process can be harnessed in several ways, improving the overall efficiency of the system. A theoretical model was prepared using COMSOL® multi-physics. The results achieved in the experimental set-up are quantified. As per the experimentation carried on the photovoltaic panel, an average temperature of 303.38 K at Standard Test Condition (STC) was achieved through cooling, while the temperature of the panel without cooling rose up to 333.15 K in environmental conditions, thus, improving the efficiency of the photovoltaic panel. The paper later applies the idea to an entire solar power plant to improve the overall efficiency of the power plant, by cooling the photovoltaic panel as well as generate hot water as its by-product.

INTRODUCTION Laser interstitial thermal therapy (LITT) is an effective minimally-invasive treatment option for intracranial tumors. Our group produced plasmonics-active gold nanostars (GNS) designed to preferentially accumulate within intracranial tumors and amplify the ablative capacity of LITT while better conforming to tumor boundaries and protecting surrounding tissue. MATERIALS AND METHODS The 12nm GNS were synthesized using reduced HAuCl4 with Na3C6H5O7 seeds, mixed with AgNO3, C6H8O6, and HAuCL4, and coated with polyethylene glycol then functionalized with methoxy PEG thiol. CT-2A glioma cells were intracranially implanted into mice, followed 18 days later by IV injection of GNS. PET-CT was performed at 10-minutes, 24-, and 72-hours post-GNS administration, with autoradiography (AR) and histopathology (HP) on sacrifice after the last scan. To test the impact of GNS on LITT coverage capacity in appropriately sized ex vivo models, we utilized agarose gel-based phantoms incorporating control and GNS-infused central “tumors” in multiple shapes. LITT was administered with the NeuroBlate System. RESULTS In vivo, GNS preferentially accumulated within intracranial tumors on PET-CT at the 24- and 72-hour timepoints. AR and HP confirmed high GNS accumulation within tumor. Ex vivo, in cuboid tumor phantoms, the GNS-infused phantom heated 5.5x faster than the control, rising 0.49°C per minute compared to 0.09°C. In a split-cylinder tumor phantom with half containing GNS, the GNS-infused border heated 2x faster and the surrounding area was exposed to 30% lower temperatures. In a GNS-infused star-shaped phantom, the heat spread contoured along phantom boundaries. CONCLUSIONS Our results provide evidence for use of GNS to improve the specificity, efficiency, and potentially safety of LITT. The in vivo data support selective accumulation within intracranial tumors, and the GNS-infused phantom experiments demonstrate increased rates of heating within the tumor model, heat contouring to tumor borders, and decreased heating of surrounding regions representing normal structures.

l -histidinium fumarate fumaric acid monohydrate (LHFFA), a new amino acid based organic single nonlinear optical crystal has been successfully grown from aqueous solution by slow solvent evaporation method. The crystal structure was determined by single crystal X-ray diffraction analysis and it belongs to monoclinic system with the space group C2. The thermal stability of the crystal has been investigated by means of thermogravimetric analysis and different thermal analysis. The result of UV–Vis study showed that the crystal was about 50% transparent in the visible region. The optical band gap of the grown crystal was also calculated. The dielectric response of the crystal with varying frequencies in the temperature region from 40 °C to 80 °C has studied. The crystal is subjected to Kurtz-Perry powder SHG test to prove its optical nonlinearity.

The internal combustion engines of automobiles generally operate around 25-40 percent conversion efficiency. The productivity of the engine can be improved by using the dissipated waste heat by the automobile cooling jacket. An ORC (Organic Rankine Cycle) unit can be installed to recover the waste heat in engine cooling jacket of a passenger car. The installation of this unit shall reduce part load from the engine by reducing the load acting directly on the alternator. The System shall increase the overall efficiency and also improves the fuel economy by using the waste thermal energy. A Thermodynamic cycle analysis and prototype fabrication of model has been considered for the experimental evaluation of the efficiency and effectiveness of ORC system. The cycle is considered using an Automotive Air-conditioning Scroll compressor as the turbine expander and also as an feed pump. Low temperature heat source from a heater is considered for the heat source in the boiler setup. The ORC turbine shall be coupled with and Electric Generator and then to the battery for recharging. The whole Setup is considered for mass production of ORC Units for cheaper price and light weight. Owing to the fact that this setup is a prototype the efficiency of the cycle can be improved further in order to careful adjustment of the critical parameters such as pressure, temperature, flow rate of the refrigerant of the thermodynamic cycle and the flow rate of the coolant according to the actual performance of the vehicle.

In the present study, TiO2 nanoparticles (NPs) have been synthesized by the sol–gel method. As synthesized, TiO2 NPs have been characterized by X-ray diffraction, high-resolution scanning electron microscopy (HR-SEM), Fourier transformation of Raman spectroscopy and UV–visible spectroscopic techniques. The different percentage of low mass concentration of TiO2 NPs have been dispersed into the mixture of ethylene glycol (EG) + water (W) and propylene glycol (PG) + water (W) in two different volume ratios (20:80 and 70:30%). The thermal and ultrasonic properties were analysed on the prepared nanofluids at the various temperature ranges from 298.15 to 323.15 K with an interval of 5 K. The 20:80% EG/W-based fluid of TiO2 nanofluids possess a higher thermal conductivity enhancement than other TiO2 nanofluids (20:80% PG/W, 70:30% EG/W and 70:30% PG/W). These results revealed that the thermal conductivity of nanofluids depends not only on nanoparticle concentrations and temperature, but also in the types of base fluids. The inter-particle interaction of nanoparticles and cluster formation have been analysed through the variation in ultrasonic parameters. Also, the thermal conductivities of nanofluids have been calculated through ultrasonic method and the results were compared with the flash laser technique method, obtained experimentally.

The different doping concentrations of lanthanum (La)-doped ZnO nanoparticles were synthesized successfully using zinc acetate and lanthanum nitrate via wet chemical method. Characterization of the prepared sample was done by standard analytical techniques such as powder x-ray diffraction analysis (P-XRD), high-resolution scanning electron microscopy (HR-SEM), energy-dispersive spectroscopy (EDS), Fourier transformer-infrared (FT-IR) spectroscopy, photoluminescence (PL) and UV-Vis spectroscopy (UV-Vis), and magnetic studies (VSM). The structural analysis has been carried out by powder x-ray diffraction. X-ray diffraction studies revealed that the nanoparticles are well-crystalline and possess hexagonal wurtzite structure. HR-SEM images showed the homogenous spherical-shaped morphology of the synthesized ZnO nanoparticles. EDS analysis confirmed the presence of La ions into ZnO lattice. The band gap (Eg) energy was determined by UV-Visible spectral data, and it was found that the Eg value decreases with increasing the La concentration into ZnO lattice. PL spectra confirmed that the effective La doping enhance the UV and visible region near band gap emission. The effect of La doping on the photocatalytic activity of ZnO nanoparticles for the degradation of methylene blue dye was studied under solar illumination and the results showed that the La doping kindles appreciable degradation of MB. The optical density measurements of the ZnO nanoparticles against both gram-positive (Bacillus subtilis, Staphylococcus aureus) as well as gram-negative bacteria (Proteus mirabilis, Salmonella typhi) showed better bacterial activity than pure ZnO. Moreover, it showed that higher dopant La in ZnO exhibit efficient antibacterial activity.

A new organic single crystal, l -histidine-2-flouro-4-nitrophenolate 2-flouro-4-nitrophenol (LHFPFP) has been synthesized at room temperature. Solution growth technique is carried out for the growth of bulk crystal. Single crystal X-ray diffraction study confirms the monoclinic crystal system with non-centrosymmetric space group, P21. Crystal show minimum absorption in the wavelength region from 480 to 900 nm. The dielectric response has been analyzed in the temperature region from 40 °C to 70 °C. Crystal display good thermal stability (182 °C) and high melting point (205 °C). Second harmonic generation test confirms the optical nonlinearity.

The structural parameters and vibrational frequency of Diazepam (DPM) are analyzed by quantum chemical methods. The FT-IR spectrum of DPM has been recorded and studied. The DFT based NMR calculatio...

In this paper, pure and rare earth (Cerium) doped ZnO nanoparticles were synthesized via simple wet-chemical technique at low temperature. The structural analyses were carried out by Powder X-ray d...