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Magnetoelectric (ME) effects in a ferromagnetic and piezoelectric composite are the changes in the polarization caused by a magnetic field or the changes in the magnetization caused by an electric field. These effects are aided by the mechanical deformation in the ferroic phases caused by the combination of magnetostriction and piezoelectricity. Interest in ME effects is due to a variety of physical phenomena they exhibit, as well as their potential applications in the creation of highly sensitive magnetic field sensors and other electronic devices. Linear ME effects in structures with layers of different ferroic materials have been studied extensively. However, nonlinear ME effects, which are caused by the nonlinearity of the magnetic, dielectric, and acoustic properties of ferromagnets and piezoelectrics, are less well understood. The purpose of this review is to summarize the current state of knowledge on nonlinear ME (NLME) effects in composite heterostructures and to discuss their potential applications. The review begins by discussing the characteristics of materials that are conductive to the occurrence of NLME effects and ferromagnetic-piezoelectric materials that are most commonly used to study such effects. The review then provides details on theoretical approaches to the description of NLME effects in heterostructures and experimental methods for studying these effects. Finally, the review presents a chronological overview of the experimentally observed NLME effects in composite structures excited by low-frequency and pulsed magnetic or electric fields. The review concludes with a discussion on the potential applications of NLME effects for highly sensitive magnetic field sensors. [ABSTRACT FROM AUTHOR]

This work reports the nucleate boiling heat transfer characteristics of n-pentane on smooth and enhanced surfaces. Surface modifications were carried out on stainless steel surfaces by fabricating microholes of diameter between 0.3 and 0.7 mm arrays using electric discharge machining. Pool boiling experiments were carried out at normal atmospheric pressure. Experiments have been performed for applied effective heat flux range between 1 and 10 W cm−2. An enhancement of 20–45% in heat transfer coefficient was observed on the enhanced surface compared to the smooth surface. The heat transfer improvement in the enhanced surface can be attributed to more active nucleation sites, better rewetting phenomenon, and favorable bubble growth and release mechanism. Further changing the material from steel to brass enhances the heat transfer coefficient by 20%. This will be a viable option as a cooling technology for high-power electronic industries. [ABSTRACT FROM AUTHOR]

As a renewable resource, seaweeds are abundant in secondary metabolites that have the potential to accelerate metabolic processes in insects, induce toxicity, alter growth and development and delay oviposition and feeding activities. The purpose of the current experiment was to examine the insecticidal activity of brown (Sargassum wightii, Stoechospermum marginatum, Turbinaria conoides) and red algal seaweeds (Gracilaria edulis, Hypnea spicifera, Liagora ceranoides) against diamondback moth under laboratory conditions in Agricultural College and Research Institute, Madurai. The marine algae were collected from Ramanathapuram districts of Tamil Nadu, India. Different extracts of seaweeds were made using the Soxhlet extraction method and were tested for toxicity at various concentrations, including 1%, 2% and 3% against a homogenous culture of second-instar Plutella xylostella larvae. Their effects were compared to those of solvents (Methanol, chloroform, hexane and acetone), a treated group (Azadirachtin 1% at 2 ml/l) and an untreated control under leaf dip bioassay with three replications in Completely Randomized Design. The larval mortality data on the treated larvae were collected systematically, statistically examined and reported. Among different concentrations of tested seaweed extracts, the highest larvicidal activity (83.33%) was observed after 72 h with Sargassum wightii methanolic extracts at 3% concentration and the least larval mortality was observed for Gracilaria edulis acetone extracts at 1% concentration (20.00%). Phytochemical profiling of all methanolic extracts of seaweeds was done by GC-MS/MS analysis. The heat map of the metabolites identified nine metabolites (6-Octadecanoic acid, Papveroline, Paroxypropione, o-Methoxymandelic acid, 11, 14-Eicosadienoic acid, Oxirane, 2-Hydroxy-5-Methyl acetophenone, Alpha-Bromo-gamma-valerolactone, 2-O-Methlyl-d-xylose) in S. wightii with high intensity that were not detected in other species. These metabolites are likely to possess insecticidal property. This study suggests the use of seaweed extracts as botanical pesticides which will be an alternative in the creation of an Integrated Pest Management (IPM) module for the control of diamondback moths. [ABSTRACT FROM AUTHOR]

Fine aggregate plays a vital role in the composition of both concrete and mortar in construction work. Excessive utilization of river sand as fine aggregate in building construction aggravates environmental degradation and underscores the need for alternate sources in the context of sustainable construction. The paper focuses on the use of crushed pebbles as a partial replacement for fine aggregate in the production of concrete. Fine aggregate was replaced partially by Pebble Sand (P-sand) in different proportions (20%, 30%, 40% and 50%) by the weight of fine aggregate in M30 grade of concrete. An experimental investigation was carried out to evaluate the mechanical (compressive, flexural and modulus of elasticity) properties of concrete with P-sand as a partial replacement for fine aggregate. The results indicate that the specimen casted with 40% replacement of P-sand to fine aggregate gave higher strength when compared to conventional concrete. [ABSTRACT FROM AUTHOR]

An experimental study was carried out to analyze the cooling curve and drying behavior of static and spin-frozen samples (distilled water and skimmed milk) in liquid immersion freeze–drying process. The freezing process was carried out in two modes: static freezing and spin freezing. Subsequently, the immersion drying process of static and spin-frozen samples was performed in a static condition. The liquid immersion method aids in heating the entire surface area of the shell containing the frozen sample, which subsequently improves the heat transfer rate and reduces the drying time. The comparison of the cooling curve of the static and spin freezing processes showed that the supercooling phenomenon has not occurred in the spin freezing process against the static one. A detailed analysis of the drying rate, drying time, moisture content retention, heat transfer coefficient, and heat load during the drying process of static and spin-frozen samples is presented in this study. The results showed that the spin-frozen sample exhibited a larger ice-vapor surface area, lower ice thickness, higher drying rate, lesser drying time, and higher heat transfer coefficient than the static-frozen sample. The product thickness attained via spin freezing is about 88% smaller than the static one. Consequently, the drying time of the spin-frozen sample is almost reduced by 80% as compared to the static case. [ABSTRACT FROM AUTHOR]

Background: Weeds are the most critical pest, which cause the highest yield reduction in food grain crops. Weeds interfere with maize growth by competing one or more growth limiting factors, controlling of weeds in maize during the critical period assumes great importance for realizing higher yield. Unavailability of relatively cheap labour in time necessitated the use of herbicides in maize. Residual impact of herbicides caused significant influence on germination and growth of succeeding crop. Methods: The field experiment was carried out during kharif 2019 at Agricultural College and Research Institute, Madurai to evaluate the residual effect of herbicides used in preceding maize on succeeding blackgram. Treatments were application of pre emergence herbicide atrazine at 0.25 kg ha-1 or pendimethalin 1 kg ha-1 applied singly on 3 days after sowing and in combination with post emergence herbicide tembotrione 120 g ha-1 or halosulfuron methyl 90 g ha-1 on 25 DAS, weed free check, unweeded check in maize crop. Result: Among the weed control treatments, pre emergence herbicides atrazine 0.25 kg ha-1 or pendimethalin 1 kg ha-1 singly and in combination with post emergence herbicides tembotrione 120 g ha-1 or halosulfuron methyl 90 g ha-1 applied in maize crop did not caused any phyotoxicity and residual impact on succeeding blackgram. However, the highest plant height (29.5 cm), dry matter production (1.17 g plant-1) and seedling vigour index (1473) of succeeding blackgram was recorded in atrazine at 0.25 kg ha-1 as pre emergence at 3 DAS followed by tembotrione at 120 g ha-1 as post emergence at 25 DAS. [ABSTRACT FROM AUTHOR]

Background: High performance hybrid broilers require a high energy diet to exploit their full genetic potential. Therefore, high energy sources are being used in broiler diet which creates interest in the use of emulsifiers along with fat source. Hence, this study was conducted to evolve emulsifier supplementation strategy in low energy diet containing tallow as fat source in commercial broiler chickens. Methods: Total of 150 day old broiler chicks randomly distributed into three treatments with 5 replicates of ten chicks each. Treatment groups were fed basal diet which contains tallow as energy source (T1), basal diet supplemented with emulsifier at 250 g per tonne of feed (T2) and 80 kcal Metabolizable energy reduced from basal diet supplemented with emulsifier at the rate of 250 g per ton of feed (T3). Result: At 6th week of age significantly highest body weight was noticed in T2 group, lowest feed intake was recorded in T2 group but feed conversion ratio was comparable between T3 (1.72) and T2 (1.74) groups. No significant difference in carcass parameters and serum biochemical parameters were noticed. Emulsifier supplementation with reduced metabolizable energy can be used as a feeding strategy in broiler chickens to improve the production performance. [ABSTRACT FROM AUTHOR]

Cotton is one of the most important commercial crops in India. Cotton growth is very slow in the initial stages of its life cycle and row spacing is wider which provides ample space for the growth of different categories of weeds and thus become a source of competition for water as well as nutrients, thereby impeding its growth. Weeds are major constraints that reduce the crop yields since they compete with crop for the nutrients, moisture, light and space. The integration of different weed management practices would be a viable option for broad spectrum weed control and enhancement of cotton productivity. Thus, weed management has several aspects such as physical, mechanical, cultural, chemical and integrated weed management methods. A brief review of research accomplishment made at various places on different fields related to this investigation is reviewed in this paper. [ABSTRACT FROM AUTHOR]

Feeder reconfiguration (FR), capacitor placement and sizing (CPS) are the two renowned methods widely applied by the researchers for loss minimization with node voltage enrichment in the electrical distribution network (EDN), which has an immense impact on economic savings. In recent years, optimization of FR and CPS together can proficiently yield better power loss minimization and save costs compared to the individual optimization of FR and CPS. This work proposes an application of an improved salp swarm optimization technique based on weight factor (ISSOT-WF) to solve the cost-based objective function using CPS with and without FR for five different cases and three load levels, subject to satisfying operating constraints. In addition, to ascertain the impact of real power injection on additional power loss reduction, this work considers the integration of dispersed generation units at three optimal locations in capacitive compensated optimal EDN. The effectiveness of ISSOT-WF has been demonstrated on the standard PG&E 69-bus system and the outcomes of the 69-bus test case have been validated by comparing with other competing algorithms. Using FR and CPS at three optimal nodes and due to power loss reduction, cost-saving reached up to a maximum of 71%, and a maximum APLR of 26% was achieved after the installation of DGs at three optimal locations with the significant improvement in the bus voltage profile. [ABSTRACT FROM AUTHOR]

The vial design feature, such as the base curvature, acts as the primary heat transfer barrier in the lyophilization process. In this study, heat and mass transport characteristics of mannitol (5%) during vial freeze-drying are numerically investigated by including the vial base curvature effects. The influence of the product fill height, chamber pressure, and the vial base curvature on the product temperature, drying time, and mass transfer resistance is analyzed in detail. The diameter of the vial is taken as 15 mm, while the fill height of the product is varied from 3 to 5 mm. The chamber pressure is maintained between 5 and 50 Pa. The results revealed that the product with a 3 mm fill height experienced a 2.5 °C lower temperature than the product with a 5 mm fill height. As opposed to the flat vial predictions, if the vial base curvature effects are considered, the drying time is increased by 1.96 and 3.8 h for the 3 mm and 5 mm fill heights, respectively. The increased drying time is attributed to the reduced direct contact area between the vial and shelf and the vapor entrainment in the gap. The results showed that the dry layer mass transfer resistance contributes to 95% of the total mass transfer resistance; however, the contribution of semi-stoppered vial resistance is 1–2% only. [ABSTRACT FROM AUTHOR]

• A review on solar dryers integrated with thermal storage unit is presented. • Covers direct, indirect and mixed mode solar dryers in active and passive mode. • Summaries works reported on sensible and latent heat storage materials. • Provides a summary on future direction of research on solar dryers with TES. Solar dryers utilise solar radiation for producing hot air to dry various food and agricultural products. The limitation of solar dryers is their inability to achieve continuous drying during off sunshine hours. Thus, solar dryers are integrated with thermal energy storage units to achieve continuous drying operation. The thermal energy storage unit employed in solar dryer consists of either sensible, latent heat storage systems or the combination of these two. The article provides an extensive review on the various sensible and latent storage units and materials used in different solar dryers viz., direct type, indirect and mixed-mode type dryers operated in both natural and forced convection. A detailed discussion on different dryer types, product dried, operating parameters, sensible and latent heat storage materials used, and their outcomes are reported and tabulated. Further, the article also provides a detailed summary on the implementation of thermal storage units in solar dryers. The future challenges and recommendations on the selection, implementation and testing of the thermal storage unit for different solar dryers are also reported. [ABSTRACT FROM AUTHOR]

• A comprehensive review on solar greenhouse dryer is presented. • Covers dryer design, mode of operation, product dried and energy aspects. • Summaries works reported on solar dryer integrated with PV and thermal storage. • Provides a summary on future direction of research on solar greenhouse dryer. This article provides an extensive review on design, thermal modelling approaches, and economic, energy and environmental aspects of solar greenhouse dryers developed for drying various agricultural products. Further, the selection and usage of solar photovoltaic panels and thermal energy storage units in the solar greenhouse dryers for achieving continuous and grid-independent drying are discussed in detail. Performances of the various configurations/shapes of the greenhouse dryers in terms of energy requirements are compared. Thermodynamic and thermal modelling studies reported on the performance prediction of solar greenhouse dryers and drying kinetics studies on various agriculture products are summarised. A detailed report on the economic (payback time, cost of the greenhouse dryer, and product drying cost), energy (embodiment energy, specific energy consumption) and environmental (CO 2 emission, CO 2 mitigation, and carbon credit) aspects of the solar greenhouse dryer based on the dryer type, mode of operation and product dried are presented. [ABSTRACT FROM AUTHOR]

The paper presents experimental investigations of metakaolin and fly ash combination of cementitious material used as admixture to produce high strength. Cement was replaced with 5%, 10%, 15%, 20% and 25% by metakaolin with addition of 10% fly ash. The paper evaluates the mechanical behavior of cement concrete using metakaolin and fly ash compared with control specimens. [ABSTRACT FROM AUTHOR]

Background: Goat farming is highly viable and Virudhunagar district of Tamil Nadu has 10 blocks out of which three blocks are situated in the foot hills of Western Ghat. There are no data available regarding Socio economic status of Goat farmers residing in foothill region of western ghat. Hence, this study was aimed to study the Socio economic status of Goat farmers in fringe villages of Western Ghat in Virudhunagar district, Tamil Nadu. Methods: Three blocks are situated in the foot hills of Western Ghat. In each block, three fringe villages near to the Western Ghat were selected randomly. In each village, 30 goat farmers were selected randomly, a total of 270 farmers were selected randomly and data were collected by personal interview through pre tested questionnaire. Result: Most of the goat farmers were between 35 to 50 years of age, owned house, lived as nucleus family, 86% of them were landless. Most of them were illiterate and not exposed to training centre. Hence, it is suggested that government or any other agency take necessary steps to expose them to scientific farming which will improve their socio economic status. [ABSTRACT FROM AUTHOR]

Composites of ferromagnetic and ferroelectric are of interest for studies on mechanical strain mediated magneto-electric (ME) interactions and for useful technologies. Here, we report on magnetic- field-assisted-assembly of barium titanate (BTO)-nickel ferrite (NFO) core-shell particles into linear chains and 2D/3D arrays and measurements of ME effects in such assemblies. First, we synthesized the core-shell nano-particles with 50-600 nm BTO and 10-200 nm NFO by chemical self-assembly by coating the ferroic particles with complementary coupling groups and allowing them to self-assemble in the presence of a catalyst via the "click" reaction. The core-shell structure was confirmed with electron microscopy and scanning probe microscopy. We obtained superstructure of the core-shell particles by subjecting them to a magnetic field gradient that exerts an attractive force on the particles and align them toward the regions of high field strengths. At low particle concentration, linear chains were formed and they evolved into 2D and 3D arrays at high particle concentrations. Magnetoelectric characterization on unassembled films and assembled arrays has been performed through measurements of low-frequency ME voltage coefficient (MEVC) by subjecting the sample to a bias magnetic field and an ac magnetic field. The MEVC is higher for fieldassembled samples than for unassembled films and is found to be sensitive to field orientation with a higher MEVC for magnetic fields parallel to the array direction than for magnetic fields perpendicular to the array. A maximum MEVC of 20 mV/cm Oe, one of the highest reported for any bulk nanocomposite, is measured across the array thickness. A model is provided for ME coupling in the superstructures of BTO-NFO particulate composites. First, we estimated the MEVC for a freestanding BTO-NFO core-shell particle and then extended the model to include an array of linear chains of the particles. The theoretical estimates are in qualitative agreement with the data. [ABSTRACT FROM AUTHOR]

The magneto-dielectric effect (MDE) involves studies on the influence of an applied magnetic field on the dielectric constant of a material. MDEs in self-assembled core-shell nanoparticles of nickel ferrite and barium titanate have been investigated in the millimeter wave frequencies. The core-shell nanocomposites were synthesized by coating 15 nm nickel ferrite and 100 nm barium titanate nanoparticles with complementary coupling groups and allowing them to self-assemble in the presence of a catalyst forming heterogeneous nanocomposites. Studies on MDE in asassembled particles have been carried out by measurements of the relative permittivity as a function of frequency f under an applied static magnetic field H over 16-24 GHz. Measurements show an H-induced decrease in permittivity by 0.8% for H= kOe and is much stronger than MDE in single phase multiferroics. A model for the high frequency MDE has been discussed here. [ABSTRACT FROM AUTHOR]

Allelopathy is the releasing of allelopathic compounds by one plant species that inhibit the growth and development of neighbouring plants of another species. Weeds, besides removing moisture and nutrients, harbour insects and diseases. Manual weed management practices are laborious and expensive. In spite of herbicides being effective in increasing yield, indiscriminate use of herbicides has resulted in serious ecological implications such as development of herbicide resistance weeds and shift in weed population. Recently, research attention has been focused to find out alternative strategies for chemical weed control in several crops. Reduction in herbicide use is one of major goals of modern agriculture and there is much emphasis in search for alternative weed management strategies that are cheap, safe and sustainable. Allelopathy is considered as an effective, economical and environment friendly weed management approach. The release of allelopathic compounds from leaves, flowers, seeds, stems and roots of living and decomposing plant materials can influence weed density and growth. Keeping this in view, the literatures on allelopathic effect of crops and trees on weeds are reviewed in this paper. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of spirit of a giant.

The need for the study arises from the requirement to improve the overall utilization of mineral admixtures (Metakaolin (MK) and Fly Ash (FA)) in correct proportions of concrete. The effect of these two mineral admixtures towards the enhancement of the strength of the concrete needs to be researched. A simple mix design procedure is also to be developed for concrete considering the efficiency of two mineral admixtures. Thus the study evaluates the effect of partial replacement of cement by mineral admixtures (MK by 0%, 5%, 10%, 15%, 20%, 25% and fly ash by 10%) on the flexural behavior of reinforced concrete beams and compares it with the beams made with conventional concrete. [ABSTRACT FROM AUTHOR]

An experimental study on heat transfer characteristics of shelf heat exchangers, which are used in small-scale freeze dryers, is presented in this paper. The proposed heat exchanger consists of the multiport mini-channel flow paths, and a comparison with a conventional serpentine is carried out based on uniformity of the product temperature achieved. The experimental results indicate that the mini-channel shelf has better temperature uniformity than the latter. Skimmed milk is used as the test fluid. In the freezing and drying process, the product temperature variation is minimal in the mini-channel heat exchanger, with a variation of 12.5 % and 25%, respectively, and the heat transfer coefficient is found to be from 140 to 267 Wm−2 K−1. The moisture content in the product reduces to 50 % in 2 hours, and the drying rate is higher at 0.032 kg hr−1 after 1 hour of the drying process. The redesign of the heat exchanger will be an essential tool to improve the performance with uniform temperature distribution on the product and to improve the product quality. [ABSTRACT FROM AUTHOR]

Low frequency dynamics of shock–turbulence interactions in constant area pipe flow with centre-line Mach number of 1.7 and friction Reynolds number of 245 is analysed using dynamic mode decomposition (DMD) of well-resolved large eddy simulation (LES) data. Two flow cases – one with a shock train and the other without shocks – are analysed. The dominant DMD modes show the near-wall sweep-ejection activity especially for the flow without shocks and also show the influence of the shocks on the near-wall organisation of the flow. The DMD modes also demonstrate a reasonable correlation between the near-wall coherent structures and the shock train for some of the modes. [ABSTRACT FROM AUTHOR]

An experimental study on formation of ice patterns during spin freezing of liquid in vials and the effect of such ice patterns in the freeze-drying process is investigated. The process is carried out in vials for liquids such as distilled water and skimmed milk which are immersed and spun in a temperature control bath maintained at −25 °C. The occurrence of different ice patterns are demonstrated using two vials with l/d ratio of 2.4 (V1) and 3.9 (V2) with the liquid fill volume varied between 20% and 85%. It is observed that depending on the l/d ratio, speed of rotation and fill volume, different ice patterns such as spiral, cone shape and uniform annular patterns occur. Also, the subsequent drying process effectively depends on the type of ice pattern that resulted in the freezing process. Among the different ice patterns, the uniform annular pattern exhibited a better drying rate. [ABSTRACT FROM AUTHOR]

The transient heat and mass transfer characteristics of the freeze-drying process of milk in a vial is numerically investigated. The paper reports the influence of semi- stoppered vial on mass transfer resistance and the relative importance of the bottom curvature of the vial on the drying time. Moreover, the variation of product temperature and mass transfer resistance as a function of time is predicted. The study revealed that the vial heat transfer coefficient strongly depends on chamber pressure; however, the effect of shelf temperature is minimal. The analysis is conducted for two fill heights (8.25 and 16.5 mm.) It is observed that the presence of curvature at the bottom of the vial increases the primary drying time but decreases the product temperature. Based on the simulation, it is observed that 16.5 mm product fill height provided higher mass transfer resistance than 8.25 mm fill height. [ABSTRACT FROM AUTHOR]

Concrete is a major material used in construction. It consists of cement, fine aggregate, coarse aggregate and water. Usually, the usage of river sand in our country is very large in the construction industry. Due to its vast use, the demand for fine aggregate is increasing day by day. Hence, it is time to find a suitable alternate to meet the demand. The paper uses two different alternatives available abundantly, Manufacturing sand (M-sand) and seashore sand, as full replacement for regular river sand. The seashore sand was tested for pH, EC, chloride, salt content, etc. M25concrete grade was used. Cube, cylinder and prism specimens were casted and tested for compressive strength, modulus of elasticity for concrete and flexural strength. In addition to this, durability test was also conducted. The results are tabulated and compared with the conventional concrete. [ABSTRACT FROM AUTHOR]

In a magnetostrictive-piezoelectric bilayer the interaction between the magnetic and electric subsystems occurs through mechanical deformation. A model is discussed here for the resonance enhancement of such magnetoelectric (ME) interactions at frequencies corresponding to bending oscillations. The thickness dependence of stress, strain, and magnetic and electric fields within a sample are taken into account so that the bending deformations could be considered in an applied magnetic or electric field. The frequency dependence for longitudinal and transverse ME voltage coefficients have obtained by solving electrostatic, magnetostatic, and elastodynamic equations. We consider boundary conditions corresponding to bilayers that are free to vibrate at both ends, or simply supported at both ends, or fixed at one end. It is shown that the bending resonance and consequent enhancement in ME coupling occurs at the lowest frequency for a bilayer that is fixed at one end and free at the other end. The model is applied to a specific case of permendur-lead zinconate titanate bilayer. The theory is in very good agreement with representative data. [ABSTRACT FROM AUTHOR]

A model is discussed for magnetoelectric interactions under ferromagnetic resonance (FMR) in bilayers of a ferrite and a functionally graded piezoelectric. A linear variation in the in-plane piezoelectric coefficient is assumed. A dc electric field E applied perpendicular to the sample plane will then result in a varying in-plane strain that is transferred to the ferrite and manifests a uniaxial magnetic anisotropy. Expressions have been obtained for microwave magnetic susceptibility, taking into account the effect of grading and substrate clamping and applied to specific cases of yttrium iron garnet/lead magnesium niobate–lead titanate (PMN-PT) and nickel ferrite/PMN-PT. The model predicts unique E dependence of microwave magnetic susceptibility and FMR absorption. With increasing E, the susceptibility is predicted to decrease, and there will be broadening of FMR absorption. The results are of interest for electric field tunable ferrite-piezoelectric microwave devices. [ABSTRACT FROM AUTHOR]

Electrically and magnetically tunable microwave resonators based on ferrite-piezoelectric layered structure have been investigated. The structure consisted of bonded layers of single-crystal yttrium iron garnet film and single-crystal lead magnesium niobate-lead titanate (PMN-PT) slab. The frequency of the resonator was tuned over a wide frequency range, from 3 to 10 GHz, by varying the bias magnetic field (magnetic tuning) and over a narrow range, up to 45 MHz, by the application of an electric field (electric tuning) to the PMN-PT layer. Performance characteristics of the resonator are discussed. The data are in good agreement with theory. [ABSTRACT FROM AUTHOR]

Laboratory bio-assay of botanicals against South American pinworm, Tuta absoluta (Meyrick, 1917) larvae showed that neem oil @ 3% and Pungam oil @ 3% recorded the maximum per cent of larval mortality (82.65% and 79.33% respectively) followed by neem seed kernal extract (NSKE) @ 5% (77.67%).From the results of field experiment of botanicals against T. absoluta the maximum reduction in larval population was recorded with neem oil @ 3% (65.26%) followed by Pungam oil @ 3% (62.30%) and NSKE @ 5% (61.15%). Fruit yield was higher in plots treated with neem oil @ 3% (17.55t/ha) followed by Pungam oil @ 3% (16.96t/ha) and NSKE @ 5% (16.77t/ha) coupled with cost benefit ratio of 1:1.65, 1:1.46 and 1:1.42 respectively. [ABSTRACT FROM AUTHOR]

The paper presents a comparative study on two types of fly ash concretes. Fly ash replacement by various percentages of 20%, 30% and 40% was made. The conventional M25 grade of concrete was made using OPC 53 grade. The optimize mix ratio and mechanical and durability properties of fly ash-based concrete are evaluated and compared with test results. [ABSTRACT FROM AUTHOR]

The paper deals with partial replacement of coarse aggregate with granite stones. The effect of Shahabad stone (a variety of cuddapah) and the chemical admixture (superflo) on concrete was investigated. Natural aggregate had been replaced with the waste shahabad stone in four different percentages, i.e., 20, 30, 40 and 50. A comparison was made between the specimens of partially replaced coarse and the same set of specimens admixed with superflo. The effects on durability properties were reported. [ABSTRACT FROM AUTHOR]

Presents a study that examined the correlation between x-ray diffraction and conductivity dependence of silver loading in thick-film thermistors. Background on the mechanism of electrical conduction in thick-film resistors; Assessment of the formulation of manganite-silver-glass thermistor inks; Analysis of the X-ray diffraction data.

Presents a study which examined brillouin light scattering for the direct detection of magnetostatic wave (MSW) excitations in a magnetostatic wave device structure. Magnetic excitations in thin films; Description of the MSW device; Intensity profiles.

This paper investigates numerically the combined effect of employing multiple Phase change materials (PCMs) and dispersion of high conductivity particles on the thermal performance of an energy storage unit. The key parameters that govern the performance have been identified following a simple reduction of variables. Among the different parameters, melting temperature of the PCMs, latent heat and melting temperature difference between two consecutive PCMs (ΔT) are found to have a significant influence on the performance. A case study considering a 3-PCM unit to study the effect of key parameters during melting has been presented. The results show that for the 3-PCM unit, the performance is better when the second and third PCMs placed have their latent heats larger than the first PCM. It has been recommended to have ΔT > ΔT for the 3-PCM unit in order achieve more melting. [ABSTRACT FROM AUTHOR]

In construction industry, concrete is the largest produced material compared to all other materials. Aggregates are the important constituents in concrete. The increase in demand for the ingredients of concrete is met by partial replacement with the waste materials obtained by means of various industries. Steel slag and marble waste are the waste products generated during the production of steel and marble, which are disposed in the form of landfills, causing an enormous amount of land pollution. Therefore, partial replacement of natural aggregates with steel slag and marble waste would lead to considerable environmental benefits which have been emphasized in this paper. Experiments were conducted and data required for mix design were obtained. M25 grade concrete is designed as per the Indian standard code. The watercement ratio is maintained for this mix design as 0.51. The steel slag and marble wastes were properly cut down to the required size of fine and coarse aggregate respectively. Then the steel slag was mixed with the concrete as fine aggregate in the percentages of 20%, 30% and 40%. It was observed that 30% was the optimum percentage replacement of fine aggregate using steel slag. Then the specimens were casted using this 30% steel slag as fine aggregate with variable percentages of marble waste as 20%, 30% and 40% as coarse aggregate subjected to curing of 28 days, from which their strength and durability properties were determined. The determined properties were compared with that of the conventional concrete. Of the above percentage mixes, partial replacement of fine aggregate by 30% steel slag and partial replacement of coarse aggregate by 40% marble waste mix were found to be favorable. [ABSTRACT FROM AUTHOR]

The membrane filtration process has been a rapidly emerging technology for removing different sizes of pollutants from untreated industrial wastewater owing to their desired merits relative to conventional treatment processes such as lower operating expenses, higher separation efficiency, smaller carbon footprint, and stable product quality. Presently, thin-film composite, blended ultrafiltration, and nanocomposite membranes provide excellent separation performance for pressure-driven water treatment techniques. In this perception, polyethersulfone (PES) based blended polymer nanocomposite (BPN) ultrafiltration membranes were fabricated for desalination applications. PES layers as support were fabricated with a blended mass of titanium dioxide (TiO2) particles and then graphene oxide (GO) particles in the nano range were combined to enhance the rejection rate and water flux of the membrane. Phase inversion and Modified Hummer's methods were adapted to prepare the layers of PES as support and graphene oxide. Blended polymer nanoparticle membrane-PES@TiO2(2%)-GO (0.5%) exhibited enhanced water flux (86.5 l m-2 h-1 bar-1), mean radius of the pore (15.9 nm), porosity (90.625%) and 86% salt rejection which proves that the membrane stands good for desalination. [ABSTRACT FROM AUTHOR]

The study was conducted to access the effect of early post-hatch nutrition regimens on the productive performance of 384 number of commercial broiler chicken (Cobb 400). Different nutrient regimens include glucose and probiotic alone in hatcher tray and first day in pen and a high and very high density diet of 25 and 27 per cent dietary crude protein respectively and 3100 kcal ME/kg diet in hatcher tray and subsequent three days in pen along with glucose and probiotic alone in hatcher tray and first day in pen was provided. Later, all broiler chicks were switched over to the recommended commercial Cobb broiler diet up to 42 days. Body weight, feed efficiency and breast muscle fibre diameter were significantly higher in treatment groups. No significant difference existed between different treatment groups for hatchability, livability percent, carcass characteristics and cut up parts. Trimmable fat per cent was significantly higher (P < 0.01) in control birds. It may be concluded that early post hatch nutrition with high nutrient dense diet resulted in better production performance in commercial broiler chicken. [ABSTRACT FROM AUTHOR]

Details a study which analyzed the structural and magnetic characteristics of radio frequency sputtered thin films of La[sub0.74]Pb[sub0.26]MnO[subz] on silicon. Methodology of the study; Measurement of magnetization properties; Temperature dependence of magnetization.

Examines the instability mechanism of collective spin wave oscillations in finite-size ferrite samples. Background of studies performed on spin wave auto-oscillations in ferrites; Model used to describe the sample-size effect in spin wave oscillations.

Presents information on a study which examined the onset of a long-range magnetic order in amorphous Bi[sub 2]-O[sub 3] ZnO Fe[sub 2] O[sub 3] films sputtered at high substrate temperatures. Status of observations in Japan regarding a ferromagnetic behavior in rapidly quenched alpha-Bi[sub 2] O[sub 3]-Fe[sub 2]O[sub 3] with substitutions; Methodology of the study; Results of the study.

Focuses on a study which examined the magnetic ordering in amorphous radio-frequency sputtered samples of bismuth iron oxide[sub3-x] copper iron[sub2] oxide[sub4] with x=0.3 through magnetization and ferromagnetic resonance measurements. Methods; Results and discussion; Conclusion.

Presents a study which examined the effects of lead substitutions on the superconducting state in compounds using a low-field alternating current susceptibility measurements on polycrystalline samples. Technique used in preparing samples of Bi-Pb-Sr-Ca-Cu-O; Observation of diamagnetism for the samples.

Presents a study which investigated the static field dependence of the frequency of auto-oscillations and the threshold microwave fields for the onset of low-frequency oscillations, subharmonic bifurcations, and chaos. Experimental details; Results and discussion; Conclusion.

Discusses a study on amorphous thin films of bismuth-iron-oxygen-lead-zirconium-oxygen. Techniques used to prepare the films; Effects of sputtering conditions and annealing at high temperature on magnetic properties of such films; Analysis of the room-temperature magnetization.

Presents a study that investigated microwave absorption in polycrystals of yttrium barium copper oxide. Estimation of the superconducting energy gap; Analysis of the x-ray diffraction pattern of the samples; Determination of the superconducting transition temperature.

Examines auto-oscillations of the dynamic magnetization and routes to chaos for the first-order transverse pump spin-wave instability in single-crystal yttrium-iron-garnet (YIG) films. Field dependence of the auto-oscillation frequency and threshold microwave field amplitude; Auto-oscillations at high microwave power levels; Chaotic dynamics in the detected microwave power for absorption in a YIG film.

Examines the use of Brillouin light scattering techniques to study ferromagnetic resonance (FMR) on thin films of permalloy and yttrium iron garnet. Advantage of Brilouin light scattering technique for FMR studies; Purpose of a backscattering geometry; Setup for microwave excitation of the samples.

Focuses on an optical observation of evanescent surface magnons in thin magnetic films. Theory for the evanescent surface waves; Identification of a type of nonpropagating surface-wave-like magnon in yttrium iron garnet films; Description of evanescent wave band limits.

Focuses on the use of Brillouin light scattering to study the critical angle behavior for magnetostatic surface waves in thin permalloy films on silicon substrates. Basic anomaly for permalloy; Details of the magnetostatic theory.