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Air Foil Thrust Bearings (AFTB) are self-acting hydrodynamic members that support axial loads of high-speed rotating turbo-machineries. The load bearing capacity of such bearings mainly depends on the foil structure. The proposed Foil Thrust Bearing of 60 mm in diameter, designed and fabricated for performance evaluation, consists of a single top foil with an inner edge height equal to that of outer edge. This paper focuses on optimizing the foil stiffness in terms of foil thickness for steel and copper foil material with 60° and 90° sector angles. Various configurations of Gas Foil Thrust Bearings (GFTB) are tested for structural stiffness and thrust loads at higher operating speeds with an instrumented test rig dedicated for the purpose. Both geometric and operating parameters are varied to determine the best possible foil stiffness that enhances the load carrying capability of the Air Foil Thrust Bearing operating under hydrodynamic condition. CFD Simulation is also carried out to indicate the pressure distribution on the foil surface for the said bearing at actual boundary conditions.

We report the mechanism to enhance the dielectric and ferroelectric behavior of polymer-ceramic composites through surface hydroxylation of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) ceramic filler-particles embedded in PVDF-HFP copolymer matrix. Varying the hydroxylated h-(BZT-BCT) filler particle-content (φ = 0–40 wt%) in PVDF-HFP copolymer matrix, composite films (of ~75 μm thickness) were prepared. We observed that, with an increase in filler content up to an optimum concentration of 15 wt%, a microstructure with gradually denser particle-arrangement and enhanced particles-polymer surface interaction is exhibited, which leads to improved dielectric and ferroelectric behavior. The energy storage density (728 mJ/cm3 at an electric field of 750 kV/cm) of the composite with 15 wt% of h-(BZT-BCT) is found to be much higher than those of the pure BZT-BCT sample, pure PVDF-HFP copolymer and their composites. Our work demonstrates the method of enhancing the functional properties through a suitable microstructure of composite materials with surface-hydroxylation of filler particles.

Zr–2.5Nb alloy, with its high yield strength and low hydrogen absorption, is used in Pressurized Heavy Water Reactor (PHWR) as pressure tube. Hydrogen in solid solution form and in hydride precipitate form may alter the mechanical properties of the Zr–2.5Nb pressure tube. In the present study, the effect of hydrogen on thermal creep behaviour of Zr–2.5Nb alloy pressure tube material is characterised in the temperature range of 350–450 °C and a stress ranging from 0.7 to 0.9 times of yield strength. The variation in rupture time, minimum creep rate, stress exponent and activation energy is determined for as-received, 150 and 200 wppm hydrogen charged samples. An attempt has been made to understand the role of hydrogen in solid solution form and as hydride precipitate form on thermal creep behaviour of Zr–2.5Nb pressure tube alloy.

Purpose The purpose of this paper is to study the comparative analysis between three hybrid nanofluids flow past a permeable stretching surface in a porous medium with thermal radiation. Uniform magnetic field is applied together with heat source and sink. Three set of different hybrid nanofluids with water as a base fluid having suspension of Copper-Aluminum Oxide (Cu−Al2O3), Silver-Aluminum Oxide (Ag−Al2O3) and Copper-Silver (Cu−Ag) nanoparticles are considered. The Marangoni boundary condition is applied. Design/methodology/approach The governing model of the flow is solved by Runga–Kutta fourth-order method with shooting technique, using appropriate similarity transformations. Temperature and velocity field are explained by the figures for many flow pertinent parameters. Findings Almost same behavior is observed for all the parameters presented in this analysis for the three set of hybrid nanofluids. For increased mass transfer wall parameter ( fw) and Prandtl Number (Pr), heat transfer rate cuts down for all three sets of hybrid nanofluids, and reverse effect is seen for radiation parameter (R), and heat source/sink parameter ( δ). Practical implications The thermal conductivity of hybrid nanofluids is much larger than the conventional fluids; thus, heat transfer efficiency can be improved with these fluids and its implications can be seen in the fields of biomedical, microelectronics, thin-film stretching, lubrication, refrigeration, etc. Originality/value The current analysis is to optimize heat transfer of three different radiative hybrid nanofluids ( Cu−Al2O3/H2O, Ag−Al2O3/H2O and Cu−Ag/H2O) over stretching surface after applying heat source/sink with Marangoni convection. To the best of the authors’ knowledge, this work is new and never published before.

Stainless steel is in great demand due to its mechanical strength, heat resistance, and resistance to corrosive environments. This article presents the result of a study of the electrochemical dissolution behavior of a stainless steel electrode (12X18H10T) at polarization by 50 Hz alternating current in a neutral medium (NaCl). Preliminary experiments have shown that the main processes do not take place when two stainless steel electrodes are polarized with an alternating current. It was observed that by the polarization of the “stainless steel – titanium” pair electrodes with alternating current, the alloy is intensively dissolved with the formation of iron (II) and chromium (III) ions. This is due to the "valve" properties of the oxide layer formed on the surface of the titanium electrode. A change in the value of the current density of the titanium and steel electrodes significantly affects the process of electrochemical dissolution of the alloy. At high current densities, the dissolution rate of the alloy decreases due to the deterioration of the current correcting properties of titanium. With an increase in the electrolyte concentration, the current efficiency is reduced as salt passivation occurs. A maximum value of the current efficiency of dissolution of stainless steel was observed at a current frequency of 50 Hz. High frequencies of the alternating current do not provide an adjustable duration of the anodic half-cycle for the oxidation reaction due to the frequent change of halfcycles of the alternating current. It was observed that increasing the temperature of the electrolyte reduces the current efficiency of the electrochemical dissolution of stainless steel electrodes. The effects of main electrochemical parameters on the electrolysis process have been investigated, and the optimal conditions of the alloy dissolution were established (іТі = 60 kA/m2 , іSS = 800 A/m2 , [NaCl] = 2.0 M, t = 30, ν = 50 Hz.).

Background Vacuum package storage is commonly applied to reduce post-harvest deterioration in minimally processed cassava roots. However, the influence of vacuum packaging conditions on root end-use quality is poorly understood. Hence, the effects of vacuum packaged storage at ambient, refrigerated and freezing temperatures on microflora, cassava tissue structure and starch extraction by wet milling were studied. Results Vacuum packaged storage temperature strongly affected cassava root quality. Minimal adverse effects were obtained with frozen storage. With refrigerated storage, there was negligible microbial growth but some disruption of the parenchyma cell wall structure suggestive of chilling injury. With ambient temperature storage, there was considerable Lactobacilli dominated fermentation. This caused substantial cell degradation, probably due to their production of extracellular cellulolytic and other cell wall degrading enzymes. A benefit of this cell wall breakdown was that it substantially improved starch extraction with wet milling from the stored cassava pieces; by 18% with pieces that had been ambient vacuum packaged and wet milled using a 2,000 μm opening screen. However, ambient temperature storage resulted in some starch granule pitting due to the action of extracellular amylases from the fermenting microorganisms. Conclusion The best vacuum packaging storage conditions for minimally processed cassava depends on application and cost. For short-term storage, refrigeration would be best for vegetable-type products. For several months storage, freezing is best. For wet milling applications, this could be combined with subsequent short-term ambient temperature storage as it improves starch extraction efficiency and could reduce distribution energy costs. This article is protected by copyright. All rights reserved.

The method of electrospark machining has proven itself well in the technology of repair and restoration of parts. The operational properties of coatings obtained by this method depend on the microstructure, chemical and phase composition of the electrode materials. A significant improvement in operational properties, for example, wear resistance, is achieved by the formation of nanostructured coatings using electrodes with a certain content of alloying nanomaterials. It is possible to obtain such materials at the lowest cost by electro-erosion dispersion of machine-building waste. This article discusses the electrodes obtained by sintering bronze powder obtained by the method of electroerosive dispersion. Such materials are new for the process of electrospark machining; therefore, it is important to study and select the optimal application modes, since a qualitative characteristic of the process is the indicator of the transfer of the electrode material to the part, which depends on the processing modes and installation parameters. The aim of the study is to select the modes of the installation for electrospark treatment for optimal deposition of the material, as well as to study the degree of coating increment during electrospark treatment. Coating was carried out using an installation for electrospark treatment mod. «Westron» type AI-007, electrode material was obtained by the technology of spark plasma sintering of bronze powder, surfacing was carried out on steel samples 14 × 14 × 40 mm in size, the work also used an Acculab ALC-210d4 analytical balance and an MG micrometer Н25 GOST 6507-90. All coatings were applied to samples with an equal area in three layers under different processing conditions. After that, the increment in the thickness and mass of the electrode material on the sample surface was measured. Based on the results of the work, formulas were obtained and graphs were built. The most optimal mode of coating with an electrode made of sintered bronze obtained from machine-building waste by the method of electroerosive dispersion was determined, which proves the consistency of this method of obtaining electrode materials.

The slow evaporation technique was adopted for the growth of L-tyrosine doped Thiourea (Bis) Cadmium Acetate (CTA) single crystal. The doped crystals were characterized by powder X-ray diffraction,...

The study aims to observe the diffusion process which is influenced by different velocity and fluid concentrations. Using a microfluidic system and the diffusion process through a reverse osmosis membrane. The research was carried out by flowing fluid into the microchannel. The diffusion process is known by measuring and analyzing the density of liquid waste aquades-trimethylene glycol. The results showed the amount of diffusion through the membrane was influenced by flow velocity and fluid concentration. this is because the velocity of the flow produces pressure on the wall so that it pushes the fluid to diffuse through the membrane.

Drug repositioning is a compelling technique to find new signs for existing medications. Despite the fact that few exploration have attempted to improve the precision of repositioning by joining information from more than one assets and various levels, it is as yet appealing to additionally review how to effectively abuse significant information for drug repositioning. As contrasted and the customary medication improvement from particle to item, drug repositioning is additional time and worth effective, quickening drug revelation technique. Medication repositioning methods might be ordered as both sicknesses based or drug-based. In this study at, propose an effective strategy, by means of utilizing Adverse Drug Reactions (ADRs) in light of the fact that the middle of the road, a heterogeneous wellbeing network containing drugs, infections, proteins and ADRs is constructed. The repositioning procedure dependent on ADR is equipped for profiling drugs related phenotypic information and can accordingly aid the resulting drugs utilize the disclosure of new recuperating.

The majority of data reported in open literature on hydride embrittlement of Zr alloys is based on hydrogen not deuterium which evolves during aqueous corrosion of in-core components in pressurized heavy water reactor operations. It is assumed that hydrogen and deuterium have similar effects on tensile properties and fracture toughness of Zr alloys. The thermal and physical properties as well as stress free transformation strain of hydrides and deuterides are different. Because of these differences, hydrogen and deuterium may affect tensile and fracture properties of Zr alloys to a different extent. The hydrogen isotope effects on tensile and fracture properties were investigated using samples machined from Zr–2.5Nb pressure tube (PT) material charged with hydrogen between 30 and 200 wppm and tests were carried out between 25 and 300 °C. The tensile properties and fracture toughness of the hydrogen charged Zr–2.5Nb PT material were compared to the Zr–2.5Nb PT material charged with deuterium. The observed effect of hydrogen isotopes on tensile and fracture toughness was rationalized in terms of stress free transformation strain and the temperature dependence of the fracture toughness of the hydrided material was correlated with the presence of axial splits on fracture surfaces. The effect of hydrogen isotope on tensile and fracture properties was investigated for the Zr–2.5Nb pressure tube (PT) material charged with hydrogen between 30 and 200 wppm and in the temperature range of 25 and 300 °C and compared with the corresponding values determined for the Zr–2.5Nb PT material charged with deuterium. It was observed that for a given concentration up to 200 wppm, hydrogen and deuterium charged Zr–2.5Nb PT material have practically same tensile and fracture properties at all test temperatures between 25 and 300 °C indicating no effect of nature of hydrogen isotope on tensile and fracture properties of Zr–2.5Nb PT material.

The results of studies of the luminescent properties of ceramics of MgF2 and MgF2, doped with tungsten trioxide, synthesized in air under the influence of a pulsed electron beam are presented. The photo- and cathodoluminescence spectra and the photoluminescence excitation spectra were studied at 300 K both in as-prepared samples and in the samples after high-temperature annealing in air. The presence of two types of luminescent centers in ceramics ware discovered: electron color centers with parameters similar to those in the crystal structure of MgF2, emitting centers of the impurity type W-O-Va, and the formation of an MgO phase in annealed ceramics.

The present study involves the study of mechanical properties such as hardness, Tensile strength and micro structure analysis. In first stage the above properties are experimentally determined for aluminium alloy without subjected to shockwaves .In second stage the specimen are subjected to shockwaves of different frequency, after the above mentioned properties are determined. Finally comparative study has been carried out to know the effect of shockwaves on the mechanical properties and microstructure. Experimentation is conducted for different frequency of shockwave. Reddy shock tube is used to produce shockwave with a Mach number of Maximum 7. Due to the application of shockwave on the surface of aluminium alloy, change in the mechanical and microstructure properties. It is observed that there an increases hardness and decrease tensile property and uniform Distribution of alloy elements. Here shockwave is applied on aluminium alloy AA6063 with the pressure ranging from 2 to 6 bar by using of Reddy shock tube. Specimen have 150 mm*150 mm sheet, of 3 mm thickness is subjected to shockwave for different pressure. Shockwave produced is propagated in driven section is record through oscilloscope. Specimens are prepared as per ASTM E8 and E10 standard. After experiment hardness test, tensile test and microstructure analysis has been carried out. The results indicates that, there is an effect of shockwave on mechanical properties and change in microstructure. Which shows that there is enhancement of the properties of alloy.

Additive manufacturing in recent years has become a popular and well-known method. The method, which involves 3D printing, provides possibilities for the creation of innovative prototypes and technologies for manufacturing. Our paper describes an idea of combining 3D printing with nanoclay. The addition of nanoclay will enhance the share of renewable raw materials that contribute to sustainable products. The structure of the filaments varies, however, as nanoclay is applied. The key goal of the paper is to establish methodologies for improving the properties of 3D composite filaments nanoclay and polyethylene. A comprehensive literature research including the extrusion, 3D printing and modern testing methods, including the 3D scanning, was paired with a large experimental analysis to evaluate printed versions. 3D printing filaments were produced for different ratios of polypropylene and nanoclay in the extruder. Significant parameters were reported for the extrusion of related content. After the introduction of nanoclay, the dimensional flexibility of polypropylene was enhanced and the deformation of the 3D printed models decreased significantly. However, fragility in filaments and 3D models increased, with the increased nanoclay ratio.

The results of the effect of scandium alloying of additive wires such as SvАМg4 and SvАМg63 on the structure and mechanical properties of welded joints of sheets and plates of 1420 alloy in mechanized single-passing and manual multi-pass welding are presented. It is shown that the introduction of 0.17...0.25 % scandium in the SvАМg4 and SvАМg63 filling wires contributes to decrease in the cracking rate and significant increase in the critical rate of deformation of the sample during welding on the МVТU sample. The level of microporosities and their location in multi-pass welding of plates of 1420 alloy depend on the magnesium content in the filling wire. The alloying of the SvАМg4 and SvАМg63 filling wires by scandium increases the ultimate strength of both the welding joint as whole and the weld metal.

The atomization process and fuel placement inside a gas turbine fuel injector are investigated at realistic operating conditions to understand the role of individual flow processes and hardware components. A high pressure, high temperature spray test facility is developed that can simulate a wide range of aero-engine operating conditions. The fuel injector is a swirl cup - dual orifice nozzle combination which is used in the rich dome combustors of various aero-engines. The internal flow field is captured using time-resolved laser induced fluorescence imaging and phase Doppler interferometry measurements. A stage-wise characterization is adopted to track the spray formation as the flow evolves through the swirl cup. The fuel placement at the cup exit is mainly decided by pilot nozzle spray characteristics and the relative momentum exchange between the gas and liquid phases. At the swirl cup exit, two class of droplets are formed: (1) droplets originated directly from the pilot nozzle, which are convected downstream by the primary air swirl, (2) droplets originated from the rim, which are atomized by the shear layer. The relative percentage of these two droplet classes depends on the pilot nozzle operation at low and high power conditions. The effect of primary spray and wall-filming are minimal towards improving the atomization. In both low and high power operating cases, the counter-rotating shear layer interactions are identified as the major mechanism that is improving the atomization process in swirl cup.

In this work the problem of free convection of the Newtonian poorly stratified liquid in the cell warmed up from left and cooled from right with the heat-insulated horizontal boarders is presented. Liquid with small concentration of salt and initial linear stratification on cell height is considered. The model of double diffusion in a Boussinesq approximation is applied to model the process. The problem is solved both in two - and three-dimensional statement by means of a control volume method and a SIMPLE algorithm. It is shown that vortex structures at the layered mode of convection have quasi-two-dimensional character.

The hard facing process is the welding process of SMAW by using a hard facing DIN 888 electrode as a hard facing to replace conventional cutting tool material. Research method is designed using factorial experiment design with 2 factors, 3 levels, and 4 iterations. The purpose of this analysis is to determine the effect of preheating temperature on the welding of hard coatings on AISI A35 low carbon steel. The results of this study are expected to obtain optimum hardness on coated steel, from variations in the temperature of the preheating. there will be a change in the hardness of the welding deposit, the deposit will be used as cutting tools. The results of this study can be used as guidelines for making cutting tools.

Li-rich cathode materials can offer a high specific capacity of ≥250 mA h g–1; however, the major issues are their structural instability, capacity degradation, and voltage decay upon prolonged cyc...

This paper presents an Artificial Neural Network (ANN) model to predict the 28-day compressive strength of roller-compacted concrete pavement (RCCP) mixes containing reclaimed asphalt pavement (RAP...

In the present work, attempts of reducing a graphene oxide powder using a low temperature hydrogenation disproportionation desorption and the recombination process (L-HDDR) has been carried out. A lower processing temperature in large scale production is significant when costs are concerned. Graphite oxide was prepared using a modified Hummers’ method dispersed in ethanol and exfoliated using ultrasonication to produce Graphene Oxide (GO). Investigations have been carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The experimental results of L-HDDR processing graphene oxide powder, using unmixed hydrogen at 400°C and relatively low pressures (

In this article the results of the negative electrode performance produced by La0.7Mg0.3Al0.3Mn0.4Co0.5Ni3.8 as-cast alloy adding 1 to 10% of carbon nanotube (CNT) or reduced graphene oxide (rGO) were investigated as Ni-MH batteries. The as cast alloy were investigated with X-ray diffraction (XRD) and scanning electron microscopy (SEM). The CNT and rGO were characterized by high resolution SEM-FEG. The discharge capacity obtained during the electrochemical characterization showed that in the addition of 1% rGO the discharge capacity was 332 mAh and 1% CNT 364 mAh , being that the rGO batteries maintaining better cyclic stability during the electrochemical test.

The equivalent series resistances (ESR) and specific capacitances (Cs) of supercapacitors carbon electrodes have been investigated using cyclic voltammetry and electrochemical impedance spectroscopy. Commercial activated carbon electrodes employing organic electrolyte have been tested using a potential window in the range of 2.7–3.8 V. Specific capacitances were calculated from cyclic voltammetry curves at room temperature employing various scan rates (30 and 100mVs-1). Internal series resistances of the supercapacitors were measured using the galvanostatic curves at room temperature and above (25 and 50°C). The ESR increase to 9.8 Ω at 25° and 2.7V to 78.8 Ω at with operating temperature raise and also with overpotential. A compositional and morphological evaluation of these electrodes showed a very homogeneous structure. It has been shown that the specific capacitance decreased considerably with scan rate, current density, electrochemical potential window and working temperature.

The storage of energy generated by photovoltaic system is one problem of it. In this aspect, integrated energy conversion and storage systems, IECSS, using supercapacitors are presented as a solution. Dye sensitized solar cell becomes a main candidate for use in IECSS due its variety of applications. Recent studies shown that zinc oxide (ZnO) is a natural candidate for use in solar cells and supercapacitor due to its high energy density of the order 650 A g-1. The aims of this paper were: i) the study of the influence of the morfology of nanostructured ZnO nanoparticles obtained by the hydrothermal method using distincts complexing agents: etylenediaminetetraacetic acid (EDTA); hexamethyltetramine (HMT) and diaminometanal (urea), besides commercial ZnO; ii) study of the ZnO and activated carbon at ratio X:Y of 10:90, 20:80 and 30:70 in proportion of mass (%) in the preparation of electrodes. The commercial ZnO, which presents particles with spherical and porous morphology, presented the best capacitance result 8.38 Fg-1 at 10:90 ratio, that demonstrates the ZnO is an excellent candidate for material for supercapacitor coupled with dye solar cell.

The microstructure, chemical composition, equivalent series resistance (ESR) and specific capacitance (Cs) of supercapacitors electrodes have been investigated. Commercial activated carbon electrodes employing organic electrolyte have been tested at a potential window of 1.1 and 2.7 V. Specific capacitances were calculated from cyclic voltammetry curves at room temperature employing various scan rates (2-70 mVs-1). Internal resistances of the supercapacitors were calculated using the galvanostatic cycling curves at several current densities (10-175 mAg-1). A maximum specific capacity of 58 Fg-1 has been achieved with the organic electrolyte at a current density of 30 mAg-1 and a potential window of 2.7V. After this initial study, the organic electrolyte was removed from the electrodes by back pumping vacuum. Two new aqueous electrolytes have been substituted in the commercial electrodes for a comparison: Na2SO4 and KOH (1.0 mol.L-1). At a discharge density of 75 mAg-1, the electrodes with KOH showed a maximum specific capacitance of 53 Fg-1 whereas the Na2SO4 showed only 6 Fg-1. ESR of the electrodes with organic electrolyte and KOH were in the range of 20 Ωcm2 whereas with Na2SO4 of 14 Ωcm2. The microstructures of the electrode material have been investigated using scanning electron microscopy (SEM) and chemical microanalyses employing energy dispersive X-ray analysis (EDX). A compositional and morphological evaluation of these electrodes showed a very homogeneous structure.

Ibuprofen is widely used as an anti-inflammatory drug. Ibuprofen crystallized from non-polar hexane exhibits needle morphology, while from polar solvents, it exhibits a plate or polyhedral morpholo...

Hierarchical 1D carbon structures are attractive due to their mechanical, chemical and electrochemical properties however the synthesis of these materials can be costly and complicated. Here, through the combination of inexpensive acetylacetonate salts of Ni, Co and Fe with a solution of polyacrylonitrile (PAN), self-assembling carbon-metal fabrics (CMFs) containing unique 1D hierarchical structures can be created via easy and low-cost heat treatment without the need for costly catalyst deposition nor a dangerous hydrocarbon atmosphere. Microscopic and spectroscopic measurements show that the CMFs form through the decomposition and exsolution of metal nanoparticle domains which then catalyze the formation of carbon nanotubes through the decomposition by-products of the PAN. These weakly bound nanoparticles form structures similar to trichomes found in plants, with a combination of base-growth, tip-growth and peapod-like structures, where the metal domain exhibits a core(graphitic)-shell(disorder) carbon coating where the thickness is in-line with the metal-carbon binding energy. These CMFs were used as a cathode in a flexible zinc-air battery which exhibited superior performance to pure electrospun carbon fibers, with their metallic nanoparticle domains acting as bifunctional catalysts. This work therefore unlocks a potentially new category of composite metal-carbon fiber based structures for energy storage applications and beyond.

The present examination is centered around the transfer of heat for the flow of a boundary layer free convective incompressible fluid, past a stretching porous surface, assuming viscosity dependent on temperature linearly along with heat source and sink with imposed magnetic field. Lie group similarity transformation is used to obtain the symmetric graphs of the given problem. Solutions for velocity and heat profile are encountered numerically with fourth-order Runga-Kutta shooting technique and graphically presented and explained the impact on velocity profile and temperature profile of several physical parameters as temperature-dependent parameter of viscosity A, k 1 as parameter of permeability, Prandtl number, λ as parameter of heat generation and absorption and M as parameter of magnetic field. We observed that the thermal boundary layer thickness can be reduced by increasing viscosity parameter A and heat sink parameter λ . As we give increment in k 1 we find a decrement in the horizontal velocity profile, which leads to the enhanced deceleration of the flow and, hence, the velocity decreases.

A promising environmentally friendly method for processing municipal solid waste is pyrolysis. Pyrolysis allows obtaining a combination of solid, liquid and gaseous products in various proportions due to changes in process parameters. A promising area for the use of solid pyrolysis products is the production of various materials for industrial, civil and road construction. There are some known methods for producing cement, concrete and foam glass with improved properties on pyrolysis basis. In modern building technologies, ceramic materials are widely used. Their production requires various expensive additives such as quartz sand, dolomite, coal, coal mining rocks, etc. Thus, it seems relevant to use the residue of the pyrolysis of municipal solid waste as a free of charge structure-forming additive for the production of ceramic material. To determine the scope of the material application and to perform subsequent thermotechnical calculations, the data on its thermophysical characteristics is required. To determine the thermophysical characteristics of the ceramic material, the experimental method of the cylindrical layer and the calculation-experimental method of inverse heat conduction problem are used. The experimental studies of thermophysical properties of the new ceramic material have allowed obtaining the dependence of the average specific heat capacity and thermal diffusivity of the ceramic material on temperatures in the range of 30–90 оС, and the coefficient of thermal conductivity on the temperatures in the range of 30–500 оС. These characteristics enable to perform calculations of thermal processes that occur in the material during its industrial use. The coefficient of thermal conductivity of the material varies from 0,3 to 0,65 W/m×K, thermal diffusivity varies within (1,8–2,3)×10–7 m2/s, and the average specific heat capacity changes from 780 to 1300 J/kg×K, which is comparable with the thermophysical characteristics of known ceramic materials. It is advisable to use the pyrolysis residue of municipal solid waste as a free raw material instead of expensive additives to obtain ceramic material. It is recommended to use the new ceramic material in the production technology of building products for various purposes.

In the present work, a modified 9Cr-1Mo steel is subjected to normalizing and tempering treatment with or without an intermediate rolling, which was carried out at 1050 °C in austenitic phase and 550 °C in metastable austenitic phase. The tempering was carried out at 700 °C and 750 °C to improve the strength by precipitation hardening and refining the microstructure. The ductile to brittle-transition temperature (DBTT) and tensile properties have been evaluated at 20 °C, 550 °C and 650 °C for the material subjected to various thermomechanical treatments. Rolling performed in austenitic phase showed improvement in the upper shelf energy and reduction in the DBTT compared with the material rolled in metastable austenitic phase. Rolling in metastable austenitic phase improved the yield strength at elevated temperature (39 pct at 20 °C, 31 pct at 550 °C and 91 pct at 650 °C) and was accompanied by a reduction in ductility (21 pct at 20 °C, 32 pct at 550 °C and 35 pct at 650 °C) compared with the as-received condition. The influence of grain size, low angle boundaries and precipitates on DBTT and high temperature strength has been studied using EBSD and TEM analyses. An increase in high temperature strength is found to increase with the area fraction of fine M23C6/MX precipitates, whereas low angle boundaries and effective grain size influenced the DBTT behavior. The combined effect of precipitation strengthening and strain hardening leads to improvement in the high temperature mechanical strength while maintaining adequate toughness. The effect of aging (for 72 hours at 650 °C) on heat-treated and -rolled samples showed a small decrease in yield strength at 20 °C. A decreasing trend of fracture toughness is observed with the increase in yield strength.

Wood plastic composites (WPC) are becoming popular in recent years, in majorly automobile and building sectors due to their attractive properties and sustainability compared to traditional materials. This work focuses at mechanical property evaluation of WPCs made of teak wood flour (wastes obtained from wood cutting mills), Poly Vinyl Chloride (PVC) and Calcium Carbonate as major ingredients. Fabrication of WPC is done using the extrusion process. Tensile, compressive, bending and impact tests were carried out as per ASTM standard testing method D 4761-19 to evaluate mechanical properties of the WPC. It was found that above said WPC has tensile strength of 7.69N/mm2, compression strength of 11.42N/mm2, flexural strength of 15.264N/mm2 and impact strength (Izod) of 0.265 N-M/mm2. From these mechanical properties of proposed PWC, it can be concluded that it can replace natural wood, when mechanical performance requirements are within above mentioned allowable values and where seasonal affect, humidity, moisture absorption etc. are the major problems. Additionally since wood waste is used in proposed PWC, material is considered more sustainable and eco-friendly. Keywords: WPC, PVC, Teak saw dust, Extrusion, ASTM, sustainable

The fact that self-compacting concrete (SCC) does not require any supplementary compaction to fill in every nook and corner of the structure without compromising with strength and durability makes it much more futuristic and desirable over conventional concrete. Present study highlights the behavioural changes in SCC for PQC applications at macro and micro levels with the incorporations of wollastonite micro-fiber; proposed to be used for restoration of deteriorated pavement quality concrete slab. Wollastonite micro-fiber was incorporated as part replacement of fine aggregates in proportions of 10–50% with an offset of 10%. Different properties of SCC mixes such as flow-ability, segregation resistance and filling ability were investigated in fresh state while mechanical properties including compressive strength, flexural strength and hardened density were studied in hardened states. The SCC mixes were also investigated for estimating effect of incorporating wollastonite micro-fiber in hydrated states of cement mortar. Inclusions of wollastonite micro-fiber in SCC enhanced the cohesiveness of the mix thereby improving the density and reducing its water absorption. SCC mixes with wollastonite micro-fiber showed higher flexural and comparable compressive strength parameters than those of conventional SCC mix. SCC mix with 30% wollastonite micro-fiber as a replacement of fine aggregates provides similar strength and better repair prospects as compared to conventional SCC or normal concrete mix.

In this communication, we report on the synthesis of vertically aligned aluminium (Al)-doped ZnO (ZnO:Al) nanowire (NW) thin films on FTO-coated glass substrates and their use as photoanode in dye-sensitized solar cells (DSSC). Very thin Al layers (∼3 nm, ∼6 nm and ∼10 nm) were deposited onto chemically synthesized ZnO nanowire film by electron-beam evaporation. The films were then subjected to rapid thermal annealing to incorporate different amounts of Al (∼0.98 at.%, 1.94 at.% and ∼2.89 at.%) into the ZnO nanowires. Optical, microstructural and compositional study of the films confirmed the growth of highly transparent and well-aligned ZnO:Al nanowires with a hexagonal crystal structure. The basic DSSC structure was fabricated using both undoped ZnO nanowire and ZnO:Al nanowire thin films as photoanode. In both cases, commercially available N3 dye was used as a photosensitizer, iodide/tri-iodide solution as electrolyte and FTO-coated glass as counter electrode. A significant increase in short-circuit current was observed, from 1.3 mA cm−2 for the pristine ZnO nanowire film-based DSSC to 4.4 mA cm−2 for the ZnO:Al (2.89 at.%) nanowire film-based DSSC. The overall power conversion efficiency (PCE) was also found to increase from 0.13% (for pristine ZnO nanowire thin film) to 0.49% for the ZnO:Al thin film-based DSSC.

Mixed molybdates of cobaltand nickel with compositional formulae Co1-xNixMoO4 (where x = 0, 0.2, 0.4, 0.5, 0.6, 0.8 and 1.0) have been synthesized by microwave-assisted co-precipitation method and examined aselectrocatalysts for oxidation of methanol and water and as supercapacitors in 1.0 M KOH.Cyclic (CV) andlinear sweep (LSV) voltammetriesand chronoamperometry techniques were used in the investigation. Structural and surface characterizations of materials were performed by XRD,Raman, SEM, HRTEM andXPS.The study has shown that introduction of Ni for Co in the CoMoO4 matrix increases the catalytic activity towards methanol (164.5 mAcm−2) and water (90 mAcm−2) oxidations, the activity, however, being the greatest with 0.5 mol Ni. Also, the capacitance of this active electrode material (611 Fg-1) was found to be much superior to pure CoMoO4(140.6 Fg-1)or NiMoO4 (89.79 Fg-1).

The article presents the results of comparative accelerated bench tests for production capacity, carrying capacity and wear resistance of materials: CT textile, Rusar and Oxafen textile. These materials are proposed for the manufacture of vacuum pump blades used in animal husbandry complexes for milking machines. From the vacuum pump depends on the performance of the milking machine, its reliability and noise level. In turn, the reliability of the pump is largely determined by the wear resistance of its blades. Therefore, the problem of choosing a lightweight, durable and wear-resistant material for the blades is crucial in their design and production. The study of the wear process under friction is associated with the need to reduce losses caused by the wear process itself. As well as with the development of effective methods for predicting the durability of friction units, ensuring their reliable operation, especially under extreme conditions. Innovative development of materials based on polymer resins with the addition of carbon, glass, fabric and other reinforcing fibers have already found wide application in aircraft manufacturing, shipbuilding, construction, and electrical engineering. Such materials have high strength and low weight, which explains the interest in their use in the production, strengthening and repair of agricultural machinery parts. The research results presented in the article provide a comparative assessment of layered plastics based on polymeric binders with the addition of reinforcing threads that have unique properties: they have high physical and mechanical properties, are resistant to long-term variable loads, to wear.

Room temperature ferromagnetism in Cluster free films of vertically aligned Fe-doped ZnO nanorods have been developed. Controlled doping was carried out by iron (Fe) ion-implantation. The metal clusters formed during implantation are dissolved into the ZnO matrix by swift heavy ion irradiation of Fe-doped films using 200 MeV sliver beam. The origin of ferromagnetism in the Fe-doped ZnO nanorods is investigated. Raman spectra show shift of ZnO phonon mode to lower frequencies due to substitution of Zn by Fe. Rutherford backscattering spectrometry (RBS) studies are carried out to estimate the film thickness and concentration of Fe-ions as well as to establish the fact that the Fe-ions are placed in the ZnO matrix. We demonstrate cluster free nature of our nanorods using magnetization versus temperature analysis and the complex impedance spectroscopic studies. Dispersion of implanted Fe and lattice defects such as oxygen vacancies are attributed to be the source of ferromagnetism in nanorods.

Thermoelastic martensitic transformation of Ti29.7Ni50.3Hf20 alloy was studied by high-resolution and in situ real-time neutron diffraction in the temperature range from 25 °C to 250 °C upon heating and cooling. It was shown that B19′ martensite phase is characterized by strong anisotropy of thermal expansion, lattice parameters of aB19′ and bB19′ increase while cB19′ and β angle decrease with increasing of temperature. Coefficients of thermal expansion for martensite and austenite were determined. The volume effect of transformation in Ti29.7Ni50.3Hf20 alloy is 0.75% which is six times larger than that of binary TiNi alloy.

Pervious concrete is special class of concrete that has application in reducing stormwater runoff and mitigation of urban heat islands (UHIs). This paper studied the morphological and pore ...

Multiple bone metastases management requires pain relief and mechanical stability to achieve functional improvement. Inducing tumour cell necrosis is important for local tumour control. A two dimensional thermal and transient numerical model based on finite element method was built to predict the temperature distribution produced by cement polymerization when mimicking a femoral lytic lesion. The bone cement filled the metastatic lesion and titanium, or CF/PEEK intramedullary nail was used. Additionally, two different cement types were compared. Cement A has low viscosity and cement B high viscosity. The titanium intramedullary nail has shown to be the best heat conductor. Significant thermal necrosis occurs with a thin or thick cement amount, and either with low or high viscosity cement types. When choosing to optimize this synergistic effect, a titanium intramedullary nail and cement A induce the largest necrotic area. The results play a role in the multidisciplinary management of long bone metastases.

The main goal of this work is to study the influence on mechanical bone behaviour using different thread profiles shapes considered in titanium dental implants. The biomechanical behaviour of bone and thread implant profile play an important role on the study of stresses and strains at bone-implant interface. The success of dental surgeries depends on the mechanical stimulus (stress, strain, strain rate, strain energy, density…) between the bone and the implant. In this work, four different threads profiles shapes were considered (Model 1 - Plateau typeA, Model 2 - Plateau typeB, Model 3 - Triangular, Model 4 - Rectangular) and for each one two internal diameters equal to 4 and 6mm. The results about the chosen thread profile shape and the diameter give additional information about the transferred stresses between bone-implant to guarantee the stability of the implant and sustain loads during or after osseointegration.

Objective The purpose of this study was to fabricate bisphenol-a glycidyl methacrylate /tri-ethylene glycol dimethacrylate (TEGDMA)-based nano and micro-sized-filled dental composite and to study the effect of varying silane-treated nano hydroxyapatite on physical, mechanical and thermal properties. Methods The dental resin matrix was fabricated by bisphenol-a glycidyl (53 wt.%), TEGDMA (46 wt.%), camphorquinone (0.3 wt.%) and 2-(dimethylamino) ethyl methacrylate (0.7 wt.%). Silane-treated nano hydroxyapatite (nHA) filler content was varied from 0 to 8 wt.%, while zinc oxide (microsized) remains constant with 20 wt.%. A light curing unit was employed for polymerization of the resinous dental mixture. Results The result revealed that infrared spectra of untreated and treated nHA filler particles were confirmed by Fourier transform infrared spectroscopy. The dental composite filled with 6 wt.% nHA (DHZ6) exhibited maximum compressive strength (249 MPa) and Vickers hardness (49 Hv), while dental composite filled with 8 wt.% nHA (DHZ8) showed minimum depth of cure (5.12 mm), degree of conversion (54%) and polymerization shrinkage (1.12%). Significance Silane treatment of nano hydroxyapatite has a significant role in physical, mechanical, and thermal properties. Bonding strength of coupling agent has been seen between organic and inorganic materials.