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In this paper, the notion of soft normal int-field over a field has been introduced. We have established a correspondence, called Soft Galois correspondence, between the soft intermediate int-fields of a finite Galois extension and the soft intgroups of the Galois group corresponding to the field extension. We have generalized some results of Galois theory in the environment of soft set theory. [ABSTRACT FROM AUTHOR]

Trapped ion modes (TIMs) belong to the family of ion temperature gradient (ITG) modes, which are one of the important ingredients in heat turbulent transport at the ion scale in tokamak plasmas. A global linear analysis of a reduced gyro-bounce kinetic model for trapped particle modes is performed, and a spectral method is proposed to solve the dispersion relation. Importantly, the radial profile of the particle drift velocity is taken into account in the linear analysis by considering the magnetic flux ψ dependency of the equilibrium Hamiltonian H e q (ψ) in both the quasi-neutrality equation and equilibrium gyro-bounce averaged distribution function F e q . Using this spectral method, linear growth rates of TIM instability in the presence of different temperature profiles and precession frequencies of trapped ions, with an approximated constant Hamiltonian and the exact ψ dependent equilibrium Hamiltonian, are investigated. The growth rate depends on the logarithmic gradient of temperature κ T , density κ n and equilibrium Hamiltonian κ Λ . With the exact ψ dependent Hamiltonian, the growth rates and potential profiles are modified significantly, compared to the cases with an approximated constant Hamiltonian. All the results from the global linear analysis agree with a semi-Lagrangian based linear Vlasov solver with good accuracy. This spectral method is very fast and requires much less computation resources compared to a linear version of the Vlasov-solver based on a semi-Lagrangian scheme. [ABSTRACT FROM AUTHOR]

Lithium orthosilicate (Li4SiO4) has the highest carbon dioxide (CO2) absorption capacity among the other lithium-based ceramic materials and is also suitable for high-temperature application for CO2 absorption. In this work, lithium orthosilicate pebbles of 1.0 mm size with 20% excess lithium carbonate were synthesized and fabricated by using Solid State Reaction Process (SSRP) and experiments were carried out to study the effect of various process parameters on its adsorption capacity of CO2 from air-CO2 mixture at elevated temperatures. The various process parameters studied were: operating gas flow rate, bed wall temperature and CO2 concentration in air on which very limited works have been reported. Effects of operating temperature, flow rate and inlet concentration of CO2 on absorption capacity have been studied to develop break through curves. The cyclic tests have been carried out with 15% CO2 concentration in air at 400°C and 200 LPH flowrate using the same material and carried out 135 consecutive absorption-desorption experimental runs. It was found that the CO2-absorption capacity of Li4SiO4 pebbles at 400°C and 200 LPH flowrates is about 31% for 30% carbon dioxide concentration in air and 22% for 15% carbon dioxide concentration in air. Moreover, no reduction in CO2-absorption capacity of the material was observed even after 135 consecutive absorption-desorption cycles. [ABSTRACT FROM AUTHOR]

Lithium orthosilicate has the highest absorption capacity among other materials used to capture carbon dioxide (CO2) at a higher temperature. To design a CO2 adsorption system consisting of lithium orthosilicate pebble bed, effective thermal conductivity and heat transfer coefficient data are necessary, and till date, these are not reported in the literature. In the present study, experiments were conducted to estimate the effective thermal conductivity and heat transfer coefficient of lithium orthosilicate pebble bed in CO2–air medium. Effects of CO2 concentration in air, bed temperature, and gas flowrate on the hydrodynamic as well as heat transfer properties of the pebble bed of lithium orthosilicate pebbles were also studied. The effective thermal conductivity and heat transfer coefficients were found in the range of 0.2–0.75 Wm−1K−1 and 14–63 Wm−2K−1, respectively. [ABSTRACT FROM AUTHOR]

In the present study, Reciprocating and Rotating Sieve Plate Column (RRSPC) was used with C6(mim)PF6; ionic liquid as dispersed phase and water as continuous phase to study hydrodynamics, which has not been studied till date. Experiments were conducted at different RPM, reciprocating pulsating frequency (RPF), dispersed phase velocity and total throughput, at different O/A ratios. It was found that disperse phase holdup increases with increase in dispersed phase velocity, total throughput (at different O/A ratios) and with increase in RPM/RPF. Simultaneous reciprocating pulsation and rotation produce good quality of dispersion of ionic liquid in range of 50 to 65 RPM/RPF. Phase inversion of dispersed phase to continuous phase takes place at 70 RPM/RPF when dispersed phase velocity ( V d ) exceeds 4.2 mm/s. Higher holdup was observed at lower RPM/RPF in RRSPC as compared to other type of column reported in literature. The optimum operating condition for RRSPC was found to be, 60–65 RPM/RPF to achieve better holdup and uniform quality of dispersion. It turned to emulsion phase above 70 RPM/RPF. Snapshots show flow visualization as well as dispersion quality. Regime maps of the system were presented to understand the mixing settler regime, dispersion and emulsion regime ranges. [ABSTRACT FROM AUTHOR]

In this paper, the minimum fluidisation velocity ( u m f ) of activated carbon particles in a gas–solid fluidised bed was experimentally determined using dry air as the fluidising medium. The effect of particle size and temperature on the minimum fluidisation velocity of the fluidised activated carbon particles was analysed. The particle sizes 212, 425, and 710 µm and bed temperatures of 30°C, 100°C, 200°C, and 300°C were studied. From the experimental results, it was found that the u m f decreased with a decrease in particle size of the activated carbon particles and decreased with an increase in the temperature. Based on the experimental results, a new correlation was developed to predict u m f at higher temperatures, since at higher temperatures, the deviation of experimental u m f values was higher when compared with the values estimated using previously published correlations. The present study will be useful for the design of an experimental system to study the continuous adsorption and desorption of organic vapours at higher temperatures in the fluidised bed of activated carbon particles. The details of the experimental study and analysis of results are discussed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, the notion of the soft Jacobson radical of a ring is defined. A relationship between the soft Jacobson radical of a ring and Jacobson semisimple ring is established. Some properties of this notion have been studied under homomorphism. [ABSTRACT FROM AUTHOR]

Trap density (Nt), density of carriers (no) and mobility are extracted in Al/beetroot/Cu Schottky diode using the Poisson's equation. The trap density and carrier concentration were found to be 1.25 × 109 and 1.8 × 109 cm–3, respectively, with the mobility 124.54 cm2 v−1 s−1 for Al/beetroot/Cu. The device shows highly asymmetric current–voltage characteristics with a good degree of nonlinearity. The diode shows an acceptable low-voltage large signal and small signal nonlinearities with asymmetry of 17.6 at 0.85 V, maximum rate of change of nonlinearity of 6 and sensitivity of 25.6 A W–1 at 0.7 V. For Al/Beet/Cu the calculated zero bias resistance is 23.3 kΩ, which is much smaller than previously reported MIM diodes. For this device fNL > 3 and fSENS > 7 A W–1, so this present device has a great potential as a rectifier. We also proposed a one-dimensional Al/organic semiconductor/Cu diode with low capacitance. The cut-off frequency of the one-dimensional Al/beetroot/Cu device is estimated as 20.8 × 1012 Hz and if the beet layer is replaced by Cur-M then the estimated frequency becomes 29 × 1012 Hz. This article also reports the comparative study between a series of natural dyes-based diodes and finally the comparison with our fabricated inorganic Al/TiO2/Cu diode. The sensitivity of Al/indigo/Cu, Al/turmeric/Cu and Al/beetroot/Cu are 0.4, 4.3 and 25.7 A W–1 with their zero-bias resistances 2.57 MΩ, 12.8 kΩ and 23.26 kΩ. Again, it was proven by the parabolic behaviour of the dI/dV vs. V plot that all-natural dye-based Schottky diodes may be affected in some way by the quantum tunnelling phenomena. Finally, the simulation was utilized to develop predicted behaviour and a better understanding of the physical mechanisms determining the effectiveness of the device under research. [ABSTRACT FROM AUTHOR]

• Sonochemical recovery of ceria from graphite substrate using Pd nanoparticles. • Mechanism of prevention of graphite exfoliation using ionic liquids. • Comparison of silent and sonochemical recovery of ceria. • Porosity and compressive strength of substrate after decontamination cycles. • Graphite erosion prevention due to TOMAC vis-a-vis imidazolium ILs. Sonochemical recovery of radioactive contaminants from nuclear graphite has been demonstrated to be quite invaluable in recent studies. However, graphite is a soft material and is prone to erosion and wear. This restricts the recycle of graphite cleaned using ultrasound beyond a few decontamination cycles. Hence, it is an imperative to prevent the surface erosion of graphite in the sonic field. The current work studies the efficacy of ultrasound in decontaminating ceria contaminated graphite coupons using a cocktail of acids (0.25 M HNO 3 − 1 M HCOOH − 0.2 M [N 2 H 5 ][NO 3 ]). Based on the superlative effects of ionic liquids in lubrication and erosion prevention, the effect of adding ionic liquid stabilized Pd nanoparticles to the leachate was also studied. It was observed that the Trioctylmethyl ammonium chloride (TOMAC) ionic liquid prevented the generation of the carbon residue due to a protective viscous layer formation reducing the mechanical effects of cavitation on graphite surface. It also helped in maintaining the porosity change in graphite microstructure around 5% after 15 cycles of decontamination. TOMAC also proved to offer better surface protection on graphite compared to imidazolium-based ILs, based on the change in compressive strength and porosity in different ionic liquids. The palladium nanoparticles, on the other hand, helped in reductive dissolution of ceria layer by acting as a reducing agent due to its lower reduction potential compared to cerium. With the surge in demand of graphite worldwide, a non-destructive decontamination process for graphite with no secondary waste generation is the need of the hour. This study is an attempt in that direction. [ABSTRACT FROM AUTHOR]

A model calculation is presented to characterize the anomalous cross field transport of electrons in a Hall thruster geometry. The anomalous nature of the transport is attributed to the chaotic dynamics of the electrons arising from their interaction with fluctuating unstable electrostatic fields of the electron cyclotron drift instability that is endemic in these devices. The electrons energy gain from those background waves leads to a significant increase in their temperature along the perpendicular direction T ⊥ / T ∥ ∼ 4 and an enhanced cross field electron transport along the thruster axial direction. It is shown that the wave-particle interaction induces a mean velocity of the electrons along the axial direction, which is of the same order of magnitude as seen in experimental observations. [ABSTRACT FROM AUTHOR]

Dewatering of alkali metal halide salts in conventional co-current or counter-current spray driers to obtain low moisture content and agglomeration in resultant dried powders is difficult owing to their hygroscopic nature. Co-current spray driers offer the advantage of good heat transport characteristics in spray zone while counter-current spray driers offer better thermal utilization throughout the drying chamber. In the present work, modified prototype of a conventional counter-current spray drier is developed to obtain both these advantages in the drying chamber by employing induction heating and mechanical pulsation techniques. After carrying out several experiments in this prototype viz. Induction heating-based pulsed spray drier (IH-PSD), the optimal process parameters are obtained which maximize thermal utilization throughout the drying chamber and minimize both moisture content and agglomeration in resultant dried powders of sodium and potassium halide salts. The initial droplet and final particle size distributions are obtained using laser diffraction analyzer and sieve shaker experiments respectively. An experimentally validated numerical model implemented using open-source computational solvers is utilized to obtain average drying rates in IH-PSD. It is observed that the average drying rate lies between 0.03 and 0.18 mg/s and 0.04 and 0.14 mg/s for sodium and potassium metal halide salts respectively. Spray drying prototype coupled with Induction heating and mechanical pulsation. Dewatering of sodium and potassium metal halide salts using the spray drying prototype. Numerical-neural network model implemented by open source computational solvers. Utilization of Laser diffraction analyser for measurement of initial droplet size. Model calculates the average drying rate with an accuracy around 83%. [ABSTRACT FROM AUTHOR]

Detection of gas molecules and volatile organic compounds (VOCs) using efficient, low cost sensors has fetched significant attention in environmental monitoring, safety measures and medical diagnosis. In the present work, nickel ferrite (NFO) nanoparticles are explored as p‐type semiconducting metal oxide (SMO) sensor for detection of five different organic vapors namely methanol, ethanol, n‐propanol, iso‐propanol and acetone which often cause severe damage to human body under prolonged exposure. The sensing studies in presence of the aforementioned five vapors are carried out by varying the sensor operating temperature (225–300 °C) and vapor concentrations (10–1000 ppm). Developed NFO sensor demonstrated best performance in terms of sensing (~10 ppm), response time (<10 s), excellent repeatability and selectivity towards ethanol among all other considered gas species. The repeatability of the sensor response is verified and the underlying reasons for the variation in the response of NFO sensor due to the change of operating temperature, analyte type and concentrations has been discussed. The synthesis of NFO through auto combustion method and study on their formation behaviour, oxygen vacancy evolution, band gap calculation, crystalline nature as well as microstructural features provides here the comprehensive information about the potential application of NFO nanoparticles as gas sensor. [ABSTRACT FROM AUTHOR]

This paper presents an accurate approach for Concentric Circular Antenna Array (CCAA) synthesis to improve the far-field radiation characteristics of the antenna using a meta-heuristic optimization technique called Moth Flame Optimization (MFO). The far-field radiation pattern improves with lower Side Lobe Level (SLL) which is essential for the reduction of interference in the entire side lobe regions. MFO algorithm is a recently proposed evolutionary algorithm which is applied to determine the optimum sets of current excitation weights and to find the optimal inter-element spacing between the array elements in the 3-rings structure of CCAA design. In this context, the design examples of two 3-ring CCAAs, one having the set of 4, 6, 8 elements and the other having the set of 8, 10, 12 elements, with and without centre element, are presented by optimizing the array parameters. The results obtained by using MFO algorithm based approach show a considerable improvement of SLL with respect to that of the uniform array pattern and those of the approaches reported in the recent literature. [ABSTRACT FROM AUTHOR]

To design passive air-cooled heat exchangers, an experimental study on natural convection in a square or rectangular duct was felt necessary, as literature on this subject is not available. In the present study, experiments were carried out using a square duct of size 500 × 500 × 800 mm height fabricated with 3.0 mm thick aluminium sheet and a brass cylinder of diameter 25 mm and height 200 mm was used as internal heat source. The heated duct was cooled by natural circulation of air. A 3D Computational Fluid Dynamics (CFD) model for natural convection with variable properties of air and no-slip condition was developed. Laminar simulations of cooling of a vertical cylinder in a rectangular duct was obtained by solving the governing equations using Fluent 6.2.16 along with Gambit v4.6.0 as pre-processor for grid generation. Grid generation resulted in 23,800 cells with 24,185 nodes. Segregated solver solution methodology has been used for simulation with implicit linearization of the Equations (10–14). Finite volume or control volume discretization technique has been used with iterative solution techniques. Residual of the order offor momentum equation, laminar model andfor energy equation was used for convergence and stability check. The solver used was based on SIMPLE algorithm. Variation of density and viscosity of air with temperature were accounted for in the simulation. The model was validated by using experimental data. Average heat transfer coefficients were estimated. It was found that the theoretically calculated average heat transfer coefficients were in good agreement with the modelled values. [ABSTRACT FROM PUBLISHER]

We report an enhanced magnetoelectric (ME) effect in spin–phonon coupled single-phase La1−xSmxYFe2O6 (0 ≤ x ≤ 1). The structural, electric, magnetic, and ME properties have been investigated to establish their interplay leading to magnetoelectricity. X-ray diffraction study suggests the facilitation of the P21nm phase (double perovskite lattice arrangements) formation and improved structural order due to the substitution of Sm in the lattice. Antiferromagnetic (AFM) transition ∼700 K along with a spin-reorientation transition around room temperature (RT) and below is observed in the thermomagnetic curve. The indication of short range ordering in the magnetization data in the form of a non-Griffiths-like phase (nGP) is observed. The short range ordering could be minimized along with consequent improvement in AFM ordering, due to Sm substitution. An enhanced (∼31% with respect to x = 0) RT first-order ME coupling coefficient ∼0.59 mV cm−1 Oe−1 in x = 0.75 composition is observed. The findings reported here open the door to exercise spin-reorientation transition in the spin–phonon coupled double perovskites for spintronic device applications. [ABSTRACT FROM AUTHOR]

Lithium-doped dysprosium oxide (LiDyO2) is a potential material for high-temperature applications of solid-state batteries. Experiments were conducted to synthesize LiDyO2by the solid-state reaction of lithium carbonate (Li2CO3) and dysprosium oxide (Dy2O3). The XRD pattern of the synthesized powder confirmed the formation of single-phase LiDyO2. From the TG-DTA study it was observed that the decomposition of Li2CO3starts at 740.9°C and the reaction between Li2CO3and Dy2O3starts at 750°C. The XRD analysis confirmed that mass loss observed in the TG-DTA study for the mixture of Li2CO3and Dy2O3at 750°C is due to the formation of LiDyO2. From the kinetic study it was found that the reaction of Li2CO3and Dy2O3follows nucleation mechanism. It was found that the best fitted model for reaction is the power law P4 nucleation model. Ozawa–Flynn–Wall method is the best suited method for fitting of the solid-state reaction model for reaction of Li2CO3and Dy2O3. The activation energy and pre-exponential factor for reaction of Li2CO3and Dy2O3were determined as 561–631 kJ/mol and 15.34–26.90 min−1, respectively. [ABSTRACT FROM PUBLISHER]

The pressurized heavy water reactors use natural uranium oxide (UO 2 ) as fuel and uses cladding material made up of zircaloy, an alloy of zirconium. Pickling of zircaloy tubes and appendages viz. , spacer and bearing pads is carried out to remove the oxide layer and surface contaminants, if present. Pickling solution, after use for many cycles i.e. , used pickling solution (UPS) is sold out to vendors, basically for its zirconium value. UPS, containing a relatively small concentration of hydrofluoric acid. After repeated use, pickling solution become saturated with zirconium fluoride complex and is treated by adding sodium nitrate to precipitate sodium hexafluro-zirconate. The remaining solution can be recycled after suitable makeup for further pickling use. The revenue lost by selling UPS is very high compared to its zirconium value, which causes monetary loss to the processing unit. Experiments were conducted to regenerate and reuse UPS which will save a good amount of revenue and also protect the environment. Experimental details and results are discussed in this paper. [ABSTRACT FROM AUTHOR]

The histology and surface ultra-structures of the gill epithelium of Labeo bata has been examined through light and electron microscopy. Gill arches bear double rows of primary lamellae and each primary lamella is provided with two rows of delicate rectangular secondary lamellae on its upper and lower surfaces. Gill arches and filaments are lined by thick stratified epithelium while the epithelium of secondary lamella is made up of thin single layered pavement cells. The thin epithelium is supported and kept apart from each other by the pillar cells. The pavement cells are polygonal with well-defined cell boundary and microridges on its apical surface. The epithelial cells are interspersed by large chloride cells located at the base of secondary lamellae and PAS positive mucous cells. Mucous cells are found abundant at the base and tip of the primary lamellae. Taste buds are found on the concave anterior faces of gill arches. The short and soft gill rakers are covered with stratified epithelium. This finding demonstrated that the fish has well developed respiratory system matching to its active life. [ABSTRACT FROM AUTHOR]

The fusion of deuterium and tritium is being considered for the energy source from fusion reactions, and on reaction each nuclei will produce one helium nuclei, one neutron and thermal energy. Deuterium is naturally available and the technologies to separate it from the compounds of hydrogen are well developed. Tritium can be produced by nuclear reaction of Li6isotope with thermal neutrons, and natural lithium contains about 7.5% Li6. Lithium has a low melting point and readily reacts with oxygen, nitrogen and moisture present in air. So, lithium-containing ceramics, namely lithium orthosilicate and lithium titanate enriched in Li6isotope, are being considered for tritium production by nuclear reaction with neutron. It was found that like lithium titanate, lithium orthosilicate can also be synthesised and pebbles can be fabricated by solid-state reaction process by using silica and lithium carbonate as raw materials. The advantage of this process is that the synthesis can be carried out at 800°C and fabricated pebbles can be sintered at 900°C to achieve the desired properties of the pebbles. Both these temperatures for synthesis and sintering are lower than that of the molten spray method. The experimental details and results are discussed in this paper. [ABSTRACT FROM PUBLISHER]

Packed pebble bed of ceramic solid breeder materials viz. lithium titanate or meta-titanate ( Li 2 TiO 3 ), lithium orthosilicate ( Li 4 SiO 4 ) etc. is being considered for fusion blankets. During the breeding of tritium, helium will be produced and also it is proposed to flow helium from outside through the bed to extract tritium, as well as to remove thermal energy from the bed. Experimental determination of thermal property data of the pebble bed under helium gas flow is important for the blanket design. Such study of determination of effective thermal conductivity with flowing helium condition was not performed previously. Though, it is known that with an increase in gas flow rate, the effective thermal conductivity of pebble bed increases, it is necessary to conduct experiments to know the exact values and the degree of variation. Model and experimental setup used in our previous study was used to for this present work. Effects of process parameters viz., helium gas flow rate, bed temperature, pebble size etc. on the effective thermal conductivity of the bed have been studied. Correlations have been developed from these experimental data to estimate effective thermal conductivity at different particle Reynold’s number and bed temperature. It was found that with the use of helium, the effective thermal conductivity of bed increases by many folds. Experimental details and results are discussed in this paper. [ABSTRACT FROM AUTHOR]

Lithium orthosilicate (Li 4 SiO 4 ) was synthesized; without and with excess lithium (Li) in quantity of its stoichiometric requirement, with 5, 10, 15 and 20% excess lithium, and pebbles were fabricated by Solid State Reaction Process (SSRP), similar to that of lithium titanate. The green pebbles were sintered at 900 °C for 6 h. XRD analysis of the synthesized powders, confirmed the formation of single phase Li 4 SiO 4 when stoichiometric ratio of lithium carbonate and silica were used and the presence of multiple phases when excess lithium was used. Morphological modifications of mesoscopic structure in Li 4 SiO 4 pebbles with different quantities of excess lithium were investigated using Ultra-Small Angle Neutron Scattering (USANS) and Scanning Electron Microscopy (SEM). USANS measurements reveal the presence of sub-micrometric pores. It also indicates density fluctuations, even at nanometer length scale. Slight variation in pore size distribution with the amount of excess lithium was observed. Average size of the pores shows a decreasing trend initially with increase in Li amount but shows an opposite trend at around 15% of excess Li. [ABSTRACT FROM AUTHOR]

Lithium titanate ( Li 2 TiO 3 ) was synthesized; without and with excess lithium (Li) in quantity of its stoichiometric requirement, with 5, 10, 15 and 20% excess and pebbles were fabricated by Solid State Reaction Process (SSRP). The green pebbles were sintered at 900 °C for 6 h . XRD analysis of the synthesized powders, confirmed the formation of single phase Li 2 TiO 3 , when 0–10% excess of lithium; compared to the stoichiometric requirement; were used and the presence of multiple phases when more than 10% excess lithium were used. Morphological modifications of mesoscopic structure in Li 2 TiO 3 pebbles with different quantities of excess lithium were investigated using Ultra-Small Angle Neutron Scattering (USANS) and Scanning Electron Microscopy (SEM). USANS measurements reveal the presence of sub-micrometric pores of size about 750 nm. From the experiments it was observed that addition of 10% of excess Li in Li 2 TiO 3 is the optimum for the Li 2 TiO 3 pebbles, in which all the desired properties remain within desired limit, without any compromise of properties of Li 2 TiO 3 pebbles. [ABSTRACT FROM AUTHOR]

Lithium titanate (Li2TiO3) and lithium orthosilicate (Li4SiO4) are the promising solid breeder materials for the fusion reactors. Packed bed of Li2TiO3or Li4SiO4pebbles is considered in the fusion reactor blanket for in situ production of tritium and for this a good effective thermal conductivity of the pebble bed is necessary. In recent past, Mandalet al.[26] studied the hydrodynamics and heat transfer properties of bed of lithium titanate pebbles at different operating conditions viz., gas flow rates, pebble sizes, bed wall temperatures, etc. In the present study laminar,k – εand low Reynoldsk – εmodel have been used to simulate the hydrodynamics and heat transfer data of Li2TiO3pebble bed. The computational fluid dynamics (CFD)-simulated hydrodynamics results have been compared with hydrodynamics and heat transfer results of bed of Li2TiO3pebbles reported by Mandal et al. [26] and others. It was found thatk – εand low Reynolds numberk – εmodel shows better agreement with experimental results. The CFD study were carried out using low Reynoldsk – εmodel for pebble bed of different materials viz. Li2TiO3, Li4SiO4and alumina (Al2O3). The effect of flow rate, pebble size, wall temperature, solid properties viz. thermal conductivity and specific heat on effective thermal conductivity and overall heat transfer coefficient has been discussed in this paper. [ABSTRACT FROM AUTHOR]

In the present study, porous titanium based composite has been developed by powder metallurgy route using cenosphere and sodium chloride (NaCl) as space holders. The effect of cenosphere particle size and sintering parameters on density, microstructure, wear and corrosion resistance has been studied. The microstructure of the composite consists of uniform distribution of cenosphere in α-Ti matrix with the presence of few TiO2 and SiO2 phases. The density of the composites varies from 1331 to 1812 kg m− 3. The kinetics and mechanism of fretting wear against hardened steel ball (at an oscillation frequency of 10 Hz) as a function of applied load (5 and 10 N) have been studied. There is a significant reduction in coefficient of friction in porous composite as compared to that of pure titanium. There is improvement in corrosion resistance in porous titanium composites as compared to as received titanium in 3.56 wt-% NaCl solution. [ABSTRACT FROM AUTHOR]

The mean particle size and size distribution of Ammonium Di-Uranate (ADU) particles, precipitated during the precipitation reaction of Uranyl Nitrate Pure Solution (UNPS) with ammonia play an important role on the sintered density of UO 2 pellets. The quality of precipitated ADU depends on number of process parameters viz. , pH of UNPS, concentration of uranium in UNPS, flow rate of ammonium hydroxide, temperature etc. However, the effects of the presence of free acid and entrained Tri-Butyl-Phosphate (TBP) in UNPS on the quality of ADU powder were not studied till date. Experiments were conducted to study the effect of free acidity and the presence of entrained TBP on the quality of precipitated ADU particles. It was found that as the concentration of free acid as well as the concentration of entrained TBP in UNPS increases, the particle size of precipitated ADU decreases. Based on the experimental results two correlations were developed to determine the mean particle size of ADU; one is based on the free acid content of UNPS and the other is based on the content of entrained TBP in UNPS, which is used for the precipitation. It was found that the correlated values are well fitted with the experimental data within ±3% errors for both the cases. Both these correlations are applicable when other process parameters remain constant. The experimental details and results are discussed in this paper. [ABSTRACT FROM AUTHOR]

The present investigation was taken up at Research Laboratory, Department of Horticulture, Aromatic and Medicinal Plants, Mizoram University, Aizawl to study the effect of nine post-harvest treatments viz., fruit dipping in NAA at 100 mg L-1, gibberellic acid at 100 mg L-1, salicylic acid at 5 mM L-1, covering the fruit with perforated polythene and newspaper bag, fruit coating with wax at 60 g L-1, fruit dipping in maleic hydrazide at 500 mg L-1, covering of fruit with dry straw and control, on fruit physico-chemical qualities and shelf life of pineapple cv. Giant Kew. Experiment was laid out in complete randomized design with three replications. Study revealed that among the different treatments, fruits treated with GA3 at 100 mg L-1 showed delayed response of ripening and high shelf life (19.05 days) during storage. At 15 DAS, skin colour remained quarter yellow (average score: 3.2), flesh colour remained more white than yellow (average score: 3), whereas, fruits showed considerably higher amount of TSS (20.41°Brix), TSS : acid ratio (20.21), total sugar (13.67%) and ascorbic acid content (18.49 mg 100 g pulp-1) with less weight loss (11.61%) due to this treatment. However, among the other treatments, SA (5.0 mM) performed well in terms of fruit physico-chemical properties and shelf life. SA treated fruits showed less external disease (average score: 1.8) and fruit decay (average score: 2.0) with high juice content (71.63%) and TSS (19.12 °Brix) at 15 DAS along with high shelf life (17.05 days). [ABSTRACT FROM AUTHOR]

Congenital pulmonary airway malformations (CPAM) is a rare developmental malformation of lower respiratory tract. However, among all congenital cystic lung lesions CPAM accounts for 95% during prenatal screening at 18 to 20 weeks. VP14.07: Congenital pulmonary airway malformations during prenatal screening: an analysis from low-resource set ups. [Extracted from the article]

We studied the roles of vitamin D and its receptor, VDR, in the progression of leprosy. The majority of individuals with leprosy from Kolkata, India, with a type 1 or type 2 reaction have low levels of vitamin D 3 in serum samples. Interestingly, individuals with a type 2 reaction associated with neuritis/erythema nodosum leprosum had very low VDR mRNA expression levels, ranging from 5% to 10%, compared to that of healthy control subjects; these patients also had a high bacilli index, ranging from 3+ to 5+. This is the first report to indicate that VDR expression levels may determine the complexity and severity of the progression of leprosy. [ABSTRACT FROM AUTHOR]

A shaped beam synthesis from a concentric ring array has been presented. Two different cases are considered. In the first case, a flat-top beam with desired specification has been generated and in the second case, a cosec 2 beam pattern from the same array configuration is generated. The desired beam pattern in each of the individual case is obtained by finding optimum excitations of the array elements using Differential Evolution (DE) algorithm. Dynamic range ratio (DRR) of the excitation amplitudes are improved by eliminating the weakly excited array elements from the optimized array without distorting the obtained pattern. To illustrate the effectiveness of DE, the two beam-patterns are computed from the same array using Genetic Algorithm (GA) by finding out optimum excitations among the elements. Results clearly show the superiority of DE over GA to handle the proposed problem. [ABSTRACT FROM AUTHOR]

Hydrodynamic properties of different particles in unary liquid–solid fluidized bed were well studied and are reported in literature. However, till date the same in liquid–solid binary packed fluidized bed has not been studied and no information is available in literature. Presently, it is well known that particles behave differently in a gas–solid packed fluidized bed; than in a unary gas–solid fluidized bed. A series of experiments were conducted to investigate the hydrodynamic characteristics of particles in liquid–solid packed fluidized bed as a function of particle size, fraction of interstitial void volume filled by particles and bed wall temperature. It was found that, like in gas–solid packed fluidized bed; the minimum fluidization velocity of particles in liquid–solid packed fluidized bed is lower than that of particles in conventional unary liquid–solid fluidized bed, but unlike gas–solid system, the minimum fluidization velocity increases with an increase in bed wall temperature. Experimental details and results are discussed in this paper. [ABSTRACT FROM AUTHOR]

Nitric acid is a commonly used dissolving agent in nuclear, chemical and metallurgical industries. All these industries generate and discharge a huge quantity of effluents containing free nitric acid and different metal nitrates. Disposal of effluents containing high nitrate concentration is a serious and global problem. Nitrate contamination in drinking water causes methemoglobinemia, a disease in which oxygen-bearing capacity of blood is reduced, which is called Blue-Baby-Syndrome. It is possible to recover and reuse nitric acid from effluents containing free nitric acid and which is the novelty of the present work. Experiments were carried out to recover nitric acid from aqueous solution containing nitric acid in absence and presence of different metal ions viz. , Na + , Mg +2 , Ca +2 and Al +3 by solvent extraction. Tributyl phosphate (TBP) was selected among several extractant because of its better selectivity towards nitric acid (HNO 3 ), overall superiority in operation, favourable physical properties and economics. The experimental details and results are discussed in this paper. [ABSTRACT FROM AUTHOR]

The sustenance of food and nutritional security are the major challenges of the 21st century. The domestic food production needs to increase per annum at the rate of 2% for cereals and 0.6% for oilseeds and pulses to meet the demand by 2030. The Indo-Gangetic Plains (IGP) and the black soil regions (BSR) are the two major food production zones of the country. Since irrigation potential is limited and expansion of irrigated area is tardy, rainfed agriculture holds promise to satisfy future food needs. Frontline demonstrations of these two regions have shown that there is a large gap at the farmers' and achievable levels of yields. This gap can be filled by adopting scientific approach of managing the natural resources. There is tremendous pressure of biotic and abiotic stresses hindering the crop production and that warrants for a systematic appraisal of natural resources. The National Bureau of Soil Survey and Land Use Planning (NBSS&LUP) under the Indian Council of Agricultural Research (ICAR) divided the country into 60 agro-ecological sub-regions (AESRs) in 1994 by superimposing maps on natural resources like soils, climate and length of growing period (LGP) for crops and other associated parameters. With the passage of nearly two decades and the advent of modern facilities of database management and improved knowledge base on natural resources, a need was felt to revise the existing AESR map to reach near the ground reality of crop performance. The new database stored in soil and terrain digital database (SOTER) has helped in modifying the AESR delineations of the BSR (76.4 m ha) and the IGP (52.01 m ha). The estimated available water content, saturated hydraulic conductivity and use of pedo-transfer functions in assessing the drainage conditions and soil quality have helped in computing with improved precision the LGP, and revise the earlier AESRs in BSR and IGP areas. This innovative exercise will be useful for the future AESR-based agricultural land use planning. [ABSTRACT FROM AUTHOR]

In the present paper, the comparison of steady, simple pulsatile flow and physiological pulsatile flow on flow reversal zone and hemodynamic wall parameters [wall shear stress (WSS) and oscillatory shear index (OSI)] for the progression of the disease, atherosclerosis has been investigated numerically. The governing equations have been solved by finite volume method. For the numerical analysis, Womersley number, Reynolds number and percentage of restriction are taken as 10, 100 and 50 % respectively. From this study it is revealed that the separated flow from the stenosis strongly depends on inlet flow situations, the maximum chance of deposition of plaque material due to streamline contour is higher at time step t* = 0.75 for simple pulsatile flow and at time step t* = 0 for physiological pulsatile flow and this chance is lower in case of steady flow. The effect of WSS on the disease is higher in physiological pulsatile flow compared to steady as well as simple pulsatile flow. The maximum possibility of initiation as well as progression for atherosclerosis in arterial wall due to high WSS takes place at t* = 0.25 for physiological pulsatile flow. OSI indicates same length of separation for two cases of transient flow, but the rate of cyclic departure of WSS is higher in case of physiological pulsatile flow. [ABSTRACT FROM AUTHOR]

Land degradation due to water erosion is a major impediment for optimum land productivity in West Bengal (WB). Sustainable development of the state needs appropriate land-use planning taking into account the heterogeneity in soil and land resources. In this study, the maximum permissible soil loss rates (T values) were computed for 115 mapping units of WB by integrating the most sensitive soil indicators such as infiltration rate, bulk density, water stable aggregates, organic carbon and fertility status to assess soil quality governing soil resistibility to erosion. For each mapping unit, indicator soil attribute values were quantitatively expressed in the 0 to 1 scale and an aggregate score was computed from the attribute scores and the corresponding weights. The results suggested a wide difference in the T values among the regions and mapping units, with values ranging from 2.5 to 12.5 Mg ha-1 yr-1. In the state as a whole, about 88% of the area has 'T' value of 12.5 Mg ha-1 yr-1. The relatively plain lands in the Indo-Gangetic plain, coastal and delta plain and the Bengal basin have a higher soil loss tolerance of about 4.0 Mg ha-1 yr-1 than the hilly and undulating regions in the Eastern Himalaya and Eastern plateau regions. The information generated will serve as a useful guide for devising differential conservation and resource use plans on the basis of soil resource potential. [ABSTRACT FROM AUTHOR]

• Intensification of recovery of ceria from graphite substrate (about 50%) using ultrasound was established. • Parametric study of reprocessing of ceria and effect of hydrogen peroxide addition to the leachant acid were reported. • The sonicated ceria recovery from substrate follows surface reaction controlled mechanism. • Graphite dust generated by graphite erosion was found to adsorb ceria from the acid leachant. • Recyclability of the parent graphite was demonstrated facilitating circular economy. There is a huge environmental concern for disposal of nuclear graphite. The current work demonstrates sonochemical decontamination of graphite using ceria coating as the simulated contamination. The ceria recovery in the leachant solution, demonstrated to drastically reduce by almost 50% beyond 30 min sonication, was attributed to the adsorption of cerium ions by the generated carbon residue due to exfoliation of graphite. The study of the carbon residue enabled to understand the anomaly in the observed kinetics and the role of the carbon residue in the removal of Ce3+ from the leach liquor. The recyclability of the graphite substrate has been studied by measuring its compressive strength and electrical conductivity before and after 7 h of sonication in nitric acid. The decontamination kinetics of graphite was found to follow the surface reaction controlled mechanism and cavitation was found to lower the activation energy from 102 to 80 kJ/mol. Overall, ultrasound was found to bring about a threefold increase in the ceria recovery over a silent process (in the absence of ultrasound). The decontamination and the recyclability of graphite demonstrated here will facilitate circular economy and serve as an important remediation technique. [Display omitted]. [ABSTRACT FROM AUTHOR]

Rampura-Agucha mines (RAM) has started journey o f capacity expansion from 1.8 Mt ore treatment (total excavation o f 11 Mt) per annum in 2003 to 5.52 Mt ore (total excavation 77 Mt) per annum in 2013-14. This exponential growth with steep business target and present depth of pit up to 300 meters warrants very innovative techniques in blasting practices with optimum use of explosive characteristics and latest initiation technology. To meet the production target and bench turnover on sustainable basis, bigger blasts by combining production and trim cut, segregate blasting to maximize ore recovery and wall stitching at geologically disturbed area are being practiced. In all these cases, selection of explosives also played an important part of the blast design and consequently, the obtainable results. With the use of blasting agents such as bulk SME, electronic detonator has been used with a desire to obtain maximum performance from the energy released by the explosives. [ABSTRACT FROM AUTHOR]

The disturbance and propagation of SH-type waves in an anisotropic soil layer overlying an inhomogeneous elastic half-space by a moving stress discontinuity is considered. Stress discontinuity moves with non-uniform velocity and is impulsive in nature. The displacements are obtained in exact form by the method due to Cagniard modified by de Hoop. The numerical result is calculated for special cases and the natures are depicted graphically. [ABSTRACT FROM AUTHOR]

Batch adsorption experiments were carried out to remove color from aqueous medium using a novel bioadsorbent prepared from bamboo leaves. Methylene blue (MB) dye was chosen as the source of color and it was adsorbed on bamboo leaves powder (BLP) and surfactant modified BLP using Triton X-100 (TX-100) and Sodium dodecyl sulfate (SDS), separately. The effects of various process parameters, viz. contact time, adsorbent dose, pH, temperature, and stirring speed were investigated in detail. Adsorption efficiencies of all the three adsorbents were compared and analyzed. The performance of SDS modified BLP was found to be excellent. Thermodynamic parameters and reaction kinetics were studied to know the nature and mechanism of adsorption. The results showed that MB adsorption followed pseudo second order kinetics and was endothermic in nature. The adsorption equilibrium was also investigated with the Langmuir, Freundlich, and Temkin isotherm models. The Langmuir isotherm was fitted well with a maximum dye uptake capacity of 125, 143, and 200 mg/g for BLP, BLP modified with TX-100, and SDS, respectively. A regeneration technique was proposed in order to reuse the adsorbent for better economy of the process. Finally, a process calculation was reported to know the amount of adsorbent required for efficient removal of MB. [ABSTRACT FROM PUBLISHER]

Abstract: Packed fluidization is a novel technique, in which small particles are allowed to fluidize in the interstices of relatively large and stationary packing to enhance heat transfer rates of a unary packed bed of same size pebbles. In the present study, heat transfer in unary packed bed and binary packed fluidized bed were investigated and compared in terms of the effective thermal conductivity. In the experimental works, large pebbles (size: 3–10mm) of two different materials viz. lithium titanate and alumina and small particles (size: 231–780μm), also of two different materials viz., lithium titanate and silica were used. It was found that the heat transfer in unary packed bed is enhanced due to the packed fluidization and in terms of the effective thermal conductivity; the enhancement was up to 260%. It was found that the volume fraction of small particles, operating gas velocity, particle to pebble size ratio and the type of materials have a significant effect in enhancing the effective thermal conductivity and heat transfer rates. It was also found that 60% (v/v) of small particles in the interstitial voids of packing pebbles can give much improved effective thermal conductivity keeping all other operating parameters same. Possible mechanism for heat transfer enhancement due to packed fluidization has been proposed. Based on the results for different particle and pebble sizes, materials and process variables viz. particles to pebble size ratios, operating gas velocity ratios, volume fraction of small particles in the interstices and bed wall temperatures, we could arrive at optimum conditions for determining effective thermal conductivity and a correlation to estimate the same. [Copyright &y& Elsevier]

Abstract: In the first generation fusion reactors the fusion of deuterium (D) and tritium (T) is considered to produce energy to meet the future energy demand. Deuterium is available in nature whereas, tritium is not. Lithium-6 (Li6) isotope has the ability to produce tritium in the n, α nuclear reaction with neutrons. Thus lithium-based ceramics enriched by Li6 isotope are considered for the tritium generation for its use in future fusion reactors. Lithium titanate is one such Li-based ceramic material being considered for its some attractive properties viz., high thermal and chemical stability, high thermal conductivity, and low tritium solubility. It is reported in the literature, that the burn up of these pebbles in the fusion reactor will be limited to only 15–17 atomic percentage. At the end of life, the pebbles will contain more than 45% unused Li6 isotope. Due to the high cost of enriched Li6 and the waste disposal considerations, it is necessary to recover the unused Li from the spent lithium titanate pebbles. Till date, only the feasibilities of different processes are reported, but no process details are available. Experiments were carried out for the recovery of Li from simulated Li2TiO3 pebbles and to reuse of lithium in lithium titanate pebble fabrication. The details of the experiments and results are discussed in this paper. [Copyright &y& Elsevier]

[Display omitted] • Intensified recovery of ceria from graphite substrate using catalyst in the presence of ultrasound. • Mechanism of catalytic recovery of ceria. • Mechanism of prevention of graphite exfoliation. • Comparison of silent and sonocatalytic recovery of ceria. • Study of control mechanism governing ceria recovery. Use of ultrasound as an intensified non-destructive decontamination technique for processing graphite limits its reusability beyond a few number of decontamination cycles due to the exfoliation of graphite due to cavitation effects. The current work establishes that the use of platinum nanoparticles in the leachant reduces the erosion of graphite substrate due to cavitation. It presents an improved way of sonochemical recovery of ceria using a mixture of nitric acid, formic acid and hydrazinium nitrate in the presence of platinum nanoparticles and ionic liquid. The platinum nanoparticles catalyst in ionic liquid prevented the generation of the carbon residue due to the combined effect of denitration and reduced sonication. The presence of the catalyst showed a fivefold increase in dissolution kinetics of ceria as well as absence of graphite erosion, facilitating better chances of graphite recycling than the decontamination without the catalyst. The catalytic approach offers a better recycle strategy for graphite with reduced exfoliation and NOx generation due to denitration, making it a more sustainable decontamination process. Since ceria is used as a surrogate for plutonium oxide, the results can be extended to decontaminate such deposits clearly establishing the utility of the presented results in the nuclear industry. [ABSTRACT FROM AUTHOR]

Abstract: In many industrial processes, solid particles of different sizes are mixed in different volume or mass fractions for various applications, primarily to reduce void volume or to increase the density of the mixture. A few of these processes include; production of high density ceramics, mortar, concrete, graphite, bricks and carbon blocks. Experiments were carried out with alumina and lithium titanate pebbles (size≥1mm) and particles (size<1mm) of different sizes and volume fractions in cylindrical and rectangular vessels to study the variation of void fraction with volume fraction of component pebbles and with large pebble to small pebble or pebble to particle size ratio. It was observed that the variation of void fraction with volume fraction of smaller pebbles or particles is ‘V-shaped’. Thus there exists a minimum void fraction and two different volume fractions of smaller pebbles or particles which can give same void fraction. The effect of void fraction on the effective thermal conductivity of binary bed of lithium titanate and alumina pebbles and particles of different sizes and volume fractions was investigated. From the experimental results it was found that the binary particulate bed has higher effective thermal conductivity that that of a unary particulate bed. Effective thermal conductivity of binary particulate bed is the maximum when its void fraction is the minimum. The binary particulate bed with less volume fraction of small particles has higher conductivity than that of the binary bed of higher volume fraction of small particles and having same void fraction. This is due to the fact that with increase in volume fraction of small pebbles or particles, the number of small-to-small and large-to-small pebbles and or particles contact point increases resulting in higher resistance to heat transfers. The experimental details and results are discussed in this paper. [Copyright &y& Elsevier]

Abstract: Uniformly sized particulate solids often fluidize poorly with bubbling and slugging. Slugging is a phenomenon associated with the geometry of the vessel, gas flow rate and properties of gas solid particles. It is severe with Geldart Group B particles especially in bed with high aspect ratio and beyond the minimum bubbling velocity. Geldart B particles fluidize well, but bubbles appear as soon as the operating gas velocity exceeds the minimum fluidization velocity. Fluidization of small Geldart B particles in the interstitial void space of large and stationary particles, called packing, overcomes these drawbacks and changes the hydrodynamic characteristics of the bed. Experiments were carried out to investigate these characteristics as a function of the size of the small particles, fraction of voids of packing filled by the small particles and bed wall temperature. Small particles in the voids of packing start to fluidize at a lower superficial velocity (flow-rate divided by empty bed cross-sectional area) than small particles in unary beds. This velocity decreases with increase in wall temperature. A correlation is proposed to estimate the minimum fluidization velocity of the small particles in the voids as a function of measurable variables. [Copyright &y& Elsevier]

The purpose of this paper is to study matrix hemiring S2 via fuzzy subsets and fuzzy h-ideals. [ABSTRACT FROM AUTHOR]

Abstract: Quality of fluidization is an important criterion for efficient heat and mass transfer in gas–solid fluidized beds. Knowledge of voidage distribution in fluidized bed is essential when exothermic reactions are carried out in fluidized beds. Quality of fluidization is often expressed in terms of time average local void-faction distribution. Gamma ray transmission technique is one of the techniques used to study the quality of fluidization. In the present study, Gamma ray transmission technique was explored to study the quality of fluidization in a unary fluidized bed and packed fluidized bed, in which small particles are fluidized in the interstitial void space of relatively large and stationary pebbles. Gamma ray photons were allowed to pass through a unary fluidized bed of silica and lithium–titanate particles at different angular and axial positions of the bed. Experiments were conducted in packed-fluidized bed of silica particles in the interstices of large size alumina pebbles and lithium–titanate particles in the interstitial void space of large size lithium titanate pebbles. It was observed, that packed fluidized bed provides better quality of fluidization or more homogeneous fluidization compared to that of a unary fluidized bed. Operating principle, experimental details and results are discussed in this paper. [Copyright &y& Elsevier]

An improved process was developed for the synthesis of hydrated tungsten oxide nanopowder from WC-6Co scrap at room temperature. This process is relatively less expensive and energy efficient. The conventional processes used for synthesizing tungsten oxide nanopowder are performed at high temperatures. In this study, tungsten oxide nanopowders are produced via electrolysis of WC-6Co pellet using sulfuric acid as an electrolyte; followed by dehydration at 150 °C. The dehydration treatment resulted in phase transformation. High purity nanorods and nanoplates of hydrated tungsten oxide were produced. The crystal size in the range of 9.6–13.8 nm was produced. The effect of process parameters on phase, crystal size, lattice strain, and morphology of tungsten oxide nanopowder is discussed. [ABSTRACT FROM AUTHOR]

This article develops an efficient and reliable evolutionary programming algorithm, namely quasi-oppositional biogeography-based optimization, for solving optimal power flow problems. To improve the simulation results as well as the speed of convergence, opposition-based learning is incorporated in the original biogeography-based optimization algorithm. In order to investigate the performance, the proposed scheme is applied on optimal power flow problems of standard 26-bus, IEEE 118-bus, and IEEE 300-bus systems; and comparisons among mixed-integer particle swarm optimization, evolutionary programming, the genetic algorithm, original biogeography-based optimization, and quasi-oppositional biogeography-based optimization are presented. The results show that the new quasi-oppositional biogeography-based optimization algorithm outperforms the other techniques in terms of convergence speed and global search ability. [ABSTRACT FROM PUBLISHER]

Abstract: Lithium titanate is a promising solid breeder material for the fusion reactor blanket. Packed lithium titanate pebble bed is considered for the blanket. The thermal energy; that will be produced in the bed during breeding and the radiated heat from the reactor core absorbed must be removed. So, the experimental thermal property data are important for the blanket design. In past, a significant amount of works were conducted to determine the effective thermal conductivity of packed solid breeder pebble bed, in helium atmosphere, but no flow of gas was considered. With increase in gas flow rate, effective thermal conductivity of pebble bed increases. Particle size and void fraction also affect the thermal properties of the bed significantly. An experimental facility with external heat source was designed and installed. Experiments were carried out with lithium-titanate pebbles of different sizes at variable gas flow rates and at different bed wall temperature. It was observed that effective thermal conductivity of pebble bed is a function of particle Reynolds number and temperature. From the experimental data two correlations have been developed to estimate the effective thermal conductivity of packed lithium-titanate pebble bed for different particle Reynolds number and at different temperatures. The experimental details and results are discussed in this paper. [Copyright &y& Elsevier]

Abstract: For the development of TBM for fusion reactors, lithium containing ceramics as against the metal are preferred as tritium breeding material. Lithium titanate (Li2TiO3) is one such chosen ceramic tritium breeder. Li2TiO3 pebbles are conventionally prepared by sol–gel process and wet process. Solid state reaction of lithium carbonate with titanium dioxide is preferred route for the bulk production of Li2TiO3. Thermo-gravimetric and differential thermal analysis (TG–DTA) techniques have been used in the present study to understand the solid state reaction of intimate mixture of lithium carbonate and titanium dioxide. It was found out that single phase lithium titanate (Li2TiO3) is produced at 750°C and the reaction is completed in 6h. Fine powders of lithium titanate obtained after milling and classification were mixed with aqueous solution of PVA to prepare green pebbles of desired size and shape. The pebbles were subsequently sintered at 900°C and the effect of sintering time on the properties of sintered pebbles was studied. The reaction mechanisms and the product qualities obtained by the solid state reaction, extrusion and spherodization techniques are discussed in this paper. [Copyright &y& Elsevier]