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The goal of this effort is to determine the interaction among the heating and cooling processes in order to understand how solids behave when subjected to temperature changes. In this instance, the temperature, displacement, and stress relations are determined analytically and numerically while a thin annular disc is subjected to both the heating and cooling processes. The ability of a material to withstand stress is essential for the design of diverse mechanical structures that aim to enhance performance, durability, characteristics, and strength. This ability is demonstrated in many physical processes where the material structure crosses over into heating and cooling processes. Furthermore, memory derivatives used in the modelling of heat transfer equations more accurately depict the memory behaviour of an imagined disc and explain its physical significance. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride) (PVDF), Barium Titanate (BaTiO3) and Montmorillonite (MMT) nanoclay based polymer nanocomposite (PNCs) were synthesized using a solution casting technique by encapsulating various loadings of BaTiO3 and MMT in PVDF matrix. The completely dispersed and highly flexible PVDF/BaTiO3/MMT nanocomposite films which were subjected to different characterization studies. The structural and morphological analysis of the synthesized nanocomposite films has been done using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). BaTiO3 and MMT reinforcement in the polymer matrix results in structural modifications of the PNCs. Thermogravimetric analysis (TGA) were employed to assess the thermal characteristics of PVDF/BaTiO3/MMT PNCs. The dielectric properties such as dielectric constant (ϵ), dielectric loss (tan δ), and AC conductivity (σac) of nanocomposite films were also examined as functions of frequency (50 Hz to 10 MHz) and temperature (30 °C to 150 °C). The highest ϵ was obtained at low frequency at higher temperatures for all the nanocomposite films. These findings imply that the PVDF/BaTiO3/MMT nanocomposites can be an effective material for energy storage applications. [ABSTRACT FROM AUTHOR]

In this work, zirconia (ZrO2) nanoparticles (NPs) incorporated poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanocomposites were fabricated at varying weight ratios through solution casting approach. The structural properties of PVDF-HFP/ZrO2 nanocomposites have been investigated by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis. The strong interaction of ZrO2 with the PVDF-HFP matrix was observed revealing the structural modifications in the nanocomposites. The thermal degradation behavior of PVDF-HFP/ZrO2 nanocomposites was investigated by thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and differential thermal analysis (DTA). Addition of ZrO2 in the PVDF-HFP matrix has greatly improved the thermal stability of the PVDF-HFP/ZrO2 nanocomposites. The dielectric properties of the PVDF-HFP/ZrO2 nanocomposites were investigated as a function of frequency and temperature. The dielectric constant was observed to be higher at low frequency and decreased abruptly on increasing the frequency. Moreover, the impedance behavior of PVDF-HFP/ZrO2 nanocomposites with different loadings was studied by plotting Nyquist plots. These results revealed that PVDF-HFP/ZrO2 nanocomposites have shown enhanced thermal, dielectric and impedance properties as compared to neat PVDF-HFP film. These significant outcomes suggest that the PVDF-HFP/ZrO2 nanocomposites hold promise as viable options for energy storage applications. [ABSTRACT FROM AUTHOR]

Background: The excessive usage of chemical fertilizers and the negligence on soil health regarding the conservation and use of organic sources of nutrients have not only caused the exhaustion of soil nutrient reserves but also resulted in soil health problems which is not conducive to achieving consistent increase in agricultural production. The beneficial influence of organic matter on the physical, chemical and biological properties of the soil is well known, the full appreciation of the same remains which is unfortunately ignored in modern agriculture. The regular recycling of organic wastes in the soil is the most efficient method of maintaining optimum nutrient reserves of soil and nutrient uptake by the plant. The present study was conducted to evaluate the nutrient status of soil under integrated usage of organic and inorganic sources. Methods: A field experiment entitled "Nutrient Management Interventions in Rice-Ragi Sequence" was conducted during kharif and rabi seasons of 2017-18 and 2018-19 on sandy loam soil of the Agricultural College Farm, Bapatla. The seven treatments consisted of T1: 100% RDF (100-60-40 kg N-P-K ha-1); T2: 100% RDF + Soil application of ZnSO4 @ 50 kg ha-1; T3: 125% RDF + Soil application of ZnSO4 @ 50 kg ha-1; T4: 75% RDF + Poultry manure @ 0.82 t ha-1 + Soil application of ZnSO4 50 kg ha-1; T5: 75% RDF + FYM @ 5.0 t ha-1 + Soil application of ZnSO4 @ 50 kg ha-1; T6: 50% RDF + Poultry manure @ 1.6 t ha-1 + Soil application of ZnSO4 @ 50 kg ha-1 and T7: 50% RDF + FYM @ 10 t ha-1 + Soil application of ZnSO4 @ 50 kg ha-1. The experiment was laidout in randomized block design with seven treatments and replicated thrice during kharif rice and in rabi each kharif treatment was subdivided into four sub treatments (S1: No fertilizer, S2: 100% RDF, S3: 75% RDF and S4: 50% RDF) and hence, the split plot design was adopted in rabi. Total no. of plots per each replication in the rabi was 28 (7-4=28). Result: Nutrient content and uptake of nitrogen, phosphorus, potassium and zinc have increased significantly with the fertility levels and organics. 50% RDF + FYM @ 10 t ha-1 + ZnSO4 @ 50 kg ha-1 recorded the highest nitrogen, phosphorus, potassium and zinc contents and uptakes in grain and straw of rice. In no till rabi ragi, N, P, K, Zn and calcium content and uptake in grain and straw were found to be significantly superior with 100% RDF (S2) to the rest of the treatments in both the years and in pooled data. [ABSTRACT FROM AUTHOR]

Magnetic and magnetocaloric properties of electron-doped Pr0.15Ca0.85MnO3 (orthorhombic space group Pnma, no. 62, oP 20) manganite have been studied. Low field magnetization measurements suggest that the sample orders antiferromagnetically at 147 K ($T_{N}$). Magnetocaloric effect (MCE) has been estimated in terms of isothermal magnetic entropy change ($\Delta S_{m}$) and the maximum $\Delta S_{m}$ value is about 6.4 Jkg−1K−1 at 137.5 K for 70 kOe field change. Low-temperature powder X-ray diffraction studies reveal a change from orthorhombic (space group Pnma, no. 62, oP 20) crystal structure to monoclinic (space group $P 2_{1}/m$ , no. 11–2, mP 20) structure below 140 K. The inverse MCE shows a maximum value around the magnetostructural transition temperature. Electrical resistivity and electron paramagnetic resonance (EPR) spectroscopy results reveal hopping conduction in the paramagnetic state. [ABSTRACT FROM AUTHOR]

Phonons and magnetic and ferroelectric ordering in La-substituted (Bi1-xLax)0.5Pb0.5Fe0.5Ti0.5O3 for samples with 0.0 ≤ x ≤ 0.5 are investigated using Raman, magnetization, and polarization measurements as a function of temperature. The system is tetragonal for pure Bi0.5Pb0.5Fe0.5Ti0.5O3 with a large c/a ratio. The anisotropy is reduced when Bi is partially replaced by La (0 ≤ x ≤ 0.5), and it turns cubic for x ≥ 0.4. All the properties are found to change significantly with changes in the c/a ratio. Evidence of spin-glass-like magnetic ordering at low temperature is found in the case of x = 0.2. A mechanism for the systematic change of magnetic ordering temperature as a function of doping is also discussed. The phonon frequencies and line widths exhibit discontinuous changes across the tetragonal-cubic transition. Large polarization and forbidden Raman scattering in the cubic phase are explained on the basis of symmetry breaking due to the formation of a polar nano region, which leads to relaxor behavior. [ABSTRACT FROM AUTHOR]

The complex perovskite system (1-x)La(MgSn)0.5O3–xNd(MgSn)0.5O3 with the composition (x=0–1) was prepared by the solid state reaction method. Structural and spectroscopic studies were carried out to understand the variation of dielectric properties with x. Rietveld refinement was carried out with the initial model obtained by using the structure prediction and diagnostic software. The symmetry of the compositions was determined to be monoclinic with space group P21/n, which corresponds to the a-a-c+ tilting system, and the long-range order parameter was found to decrease with an increase in neodymium concentration. Raman spectra were analyzed by fitting the A1g-like mode to a Lorentzian peak shape. Intrinsic dielectric parameters were estimated by fitting infrared reflectance spectra with the four-parameter semiquantum model. Transverse optic phonon mode strengths and average phonon damping were calculated. The origin of increase in the intrinsic loss with the composition variation is discussed. Microwave measurements were carried out in the frequency range of 9–11 GHz. The dielectric constant decreases and the temperature coefficient of resonant frequency becomes less negative with the increase in neodymium concentration. [ABSTRACT FROM AUTHOR]

La(Mg0.5Ti(0.5-x)Snx)O3 perovskite ceramics with composition (x=0.0-0.5) are prepared by the solid state reaction method. The ceramics are characterized by x-ray diffraction, far-infrared reflectance, Raman spectroscopy, and microwave dielectric properties. The symmetry of ceramics is monoclinic with P21/n space group. Intrinsic dielectric constant and loss are estimated by fitting reflectance to the four-parameter semiquantum model. Transverse optic phonon mode strengths and average phonon damping are calculated. The modes corresponding to B-site ordering are identified in Raman spectra and the A1g mode of La(MgTi)0.5O3 is analyzed by assuming two merging modes. The variation of long-range order is correlated with full width half maximum of the A1g mode. Microwave measurements are carried out in the frequency range of 8–10 GHz. The dielectric constant ([variant_greek_epsilon]′) is found to gradually decrease from 28.4 to 19.7 with an increase in tin concentration, whereas the temperature coefficient of resonant frequency (τf) decreases from -68 to -84 ppm/°C. The product of the quality factor and resonant frequency (Q×f) obtained for La(MgTi)0.5O3 is 55,000 GHz, that decreases to 46,000 for x=0.25 composition and then increases to 63,000 GHz for La(MgSn)0.5O3. [ABSTRACT FROM AUTHOR]

The ordered complex perovskite lead ytterbium tantalate undergoes a change in structural and dielectric properties as the concentration of Ba increases. The x-ray diffraction patterns show a decrease in the intensity of superlattice reflections due to Pb-antiparallel displacement as well as to B-site ordering. The structure approaches cubic symmetry with increase in Ba content. The dielectric response shows a gradual change from antiferroelectric to relaxor ferroelectric and then the relaxor behavior starts decreasing as Ba content increases. Raman-scattering study of the samples shows that some of the modes seen for Pb(Yb0.5Ta0.5)O3 disappear and an additional mode appears at 420 cm-1 with increase in Ba concentration. A qualitative analysis of various modes suggests that the substitution of Ba for Pb leads to a decrease in the degree of ordering and occurrence of local distortions in the lattice as evidenced by the broadening of certain peaks in the Raman spectra. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the effect of chemical defoliation on growth parameters, seed cotton yield and economics of cotton under high density planting during kharif, 2016. Defoliation with Etherel @ 2000 ppm at 60 boll opening percentage resulted in higher number of picked bolls plant-1 and boll opening percentage and seed cotton yield (2359 kg ha-1). At harvest, significantly highest drymatter accumulation was recorded with Urea @ 15% (T6) (22692 kg ha-1). Dropp Ultra 560 SC (Thidiazuron 360 + Diuron 180) @ 200 ml/ha recorded significantly higher leaf defoliation (99.7 %) and was superior over other defoliants tried. Application of defoliants i.e., Dropp Ultra and Etherel at 60 BOP resulted in reduction of crop duration by 20 days. [ABSTRACT FROM AUTHOR]

Investigates the electrical conductivity and thermoelectric power of some lithium-titanium ferrites with small amounts of manganese and zinc. Variations in conductivity; Measurements of electrical conductivity; Stoichiometric formula for ferrites.

Discusses the optimum parameters for good dielectric resonator materials. Identification of parameters responsible for the change in dielectric properties; Reason for choosing an exponential function for the dependence of k value; Possible effect of the expanded electron cloud of the lanthanide ions.