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This paper adopts the multi-criterion decision-making model of fuzzy-TODIM and genetic algorithm (GA) for optimal portfolio allocation. We applied Markowitz's portfolio parameters as inputs for the fuzzy TODIM model to rank stocks that are constituents of each index from three different markets. Portfolios are then generated dynamically using three weighting techniques and subject to multi-objective criteria and additional constraints. The results indicate a significant variation in performance metrics between the model-generated portfolios and the market indices. Replication of the procedure produces a similar outcome. Moreover, the out-of-sample tests conducted over 3 years validate the results' robustness, indicating that fuzzy TODIM, combined with GA, can achieve superior performance in dynamic portfolio allocation. [ABSTRACT FROM AUTHOR]

Recently, molten salt corrosion of metallic alloys in concentrated solar power (CSP) industries is one of the important and unavoidable issues among others. In this investigation, the role of inhibitor (i.e., Mg powder) on the hot corrosion behavior of Inconel 617 superalloy in molten chloride salts mixture has been examined through immersion corrosion test method and electron microscopic analysis. Post corrosion observations revealed that Cr at the grain boundary is preferentially depleted, which leads to severe grain boundary corrosion. By addition of 1 wt% Mg powder (as inhibitor), the corrosion rate (derived through percolation depth) was observed to be remarkably minimized by ~ 40% compared with the immersion test without Mg powder addition. The notable increase in corrosion resistance by the addition of Mg powder could be attributed to the reduction of oxidizing impurities in the molten salts mixture, which is considered to be the main culprit for the corrosion promoter. [ABSTRACT FROM AUTHOR]

Ferroelectric materials exhibiting switchable and spontaneous polarization have strong potential to be utilized in various novel electronic devices. Solid solutions of different perovskite structures induce the coexistence of various phases and enhance the physical functionalities around the phase coexistence region. The construction of phase diagrams is important as they describe the material properties, which are linked to the underpinning physics determining the system. Here we present the phase diagram of (K0.5Na0.5NbO3)–(Ba0.5Sr0.5TiO3) (KNN-BST) system as a function of composition and their associated physical properties. Lead-free (1 − x)KNN–xBST (0 ≤ x ≤ 0.3) solid solution ceramics were synthesized by conventional solid-state reaction technique. The X-ray diffraction and Raman spectroscopic studies indicate composition-dependent structural phase transitions from an orthorhombic phase for x = 0 to orthorhombic + tetragonal dual-phase (for 0.025 ≤ x ≤ 0.15), then a tetragonal + cubic dual-phase (x = 0.2) and finally a cubic single phase for x ≥ 0.25 at room temperature (RT). Among these, the orthorhombic + tetragonal dual-phase system shows an enhanced value of the dielectric constant at room temperature. The phase transition temperatures, orthorhombic to tetragonal (TO-T) and tetragonal to cubic (TC), decrease with the increase in BST concentrations. The ferroelectric studies show a decrease of both 2Pr and EC values with a rise in BST concentration and x = 0.025 showed a maximum piezoelectric coefficient. [ABSTRACT FROM AUTHOR]

In this article, we present the results of low-temperature dielectric, magnetic and magnetodielectric properties of BiFeO3 nanoceramics prepared by auto-combustion method. Rietveld refinement results of X-ray diffraction data show that sample crystallizes in single-phase rhombohedral perovskite structure with R3c (No. 161) space group. The average crystallite size was found to be ≈ 600 Å from Williamson–Hall analysis. The temperature-dependent dielectric data have been presented in permittivity and modulus formalism to understand the relaxation dynamics. Three non-Debye-type relaxation processes were observed in the experimental window (173 to 423 K), which are explained using Kohlrausch–Williams–Watts (KWW) decay function. The temperature variation of relaxation times obeys Arrhenius's behaviour. The anomaly observed in the temperature dependence of relaxation times data near 240 K corresponds to the magnetic transition of BiFeO3. We found that single ionized oxygen vacancies with activation energy ranging from 0.4 to 0.8 eV are involved in the relaxation process. A crossover from AFM/PM to weak ferromagnetic ordering is observed at low temperature. The variation of capacitance with an applied magnetic field shows a hysteresis effect. The magnetocapacitance (MC%) changes by 3% at a magnetic field of 2 T for 200 kHz, indicating an intrinsic bulk magnetocapacitance effect in the ceramics. Hence, the above findings highlight the significance of the material as a potential candidate for device applications. [ABSTRACT FROM AUTHOR]

This study explores the effects of filler concentrations of lanthanum-doped lead zirconate titanate (PLZT) on the electrical and mechanical characteristics of nanocomposite thick film. Crystal structure and morphology of the thick film have been studied using X-ray diffraction, atomic force microscopy, and scanning electron microscopy techniques. It has been noted that adding PLZT nanoparticles to the polyvinylidene fluoride (PVDF) matrix modifies the physical properties of PVDF. In the nanocomposite film, the most prominent polar β phase has been identified at 6 mol% of PLZT filler. In all the films, a nearly homogenous grain distribution has been observed. Frequency-dependent dielectric, conductivity, and impedance of the sample were studied at room temperature. Maximum electric dipole polarization of 0.68 μC/cm2 and piezoelectric (d33) constant of 48 pC/N have been observed at 6 mol% of PLZT filler in the PVDF matrix. Indeed, it has been observed that the (0.94)PVDF–(0.06)PLZT nanocomposite film is well suited for applications such as nanogenerators, structural health monitoring systems, and various kinds of sensors and actuators. [ABSTRACT FROM AUTHOR]

Compound extreme events, such as flash drought, have received wide attention in recent decades due to their far-reaching effects on the ecosystem. Thus, a new concept of flash drought has begun to spread globally in the scientific community, and it is continuously being developed. This study offers for the first time an overview of the global trends in flash drought research from 2000 to 2021. The analysis was based on the Scopus database in order to investigate the publication trends, contributions, collaborations, and challenges on a global scale. Furthermore, collaboration analysis was performed to detect collaboration networks within the flash drought research field. A total of 76 studies were published during the study period. The research output grew exponentially with an average growth rate of 30% per year. The challenging issues in the field of flash drought research are the search for appropriate definition of flash drought, the development of effective early warning systems and the scarcity of high-resolution data. By presenting the details of the evolution of this new conceptualization in drought research, our study highlights the main pathways of scientific progress and stimulates future research. [ABSTRACT FROM AUTHOR]

Inspired by massive parallelism, an increase in internet-of-things devices, robust computation, and Big-data, the upsurge research in building multi-bit mem-transistors is ever-augmenting with different materials, mechanisms, and state-of-the-art architectures. Herein, we demonstrate monolayer WS2-based functional mem-transistor devices which address nonvolatility and synaptic operations at high temperature. The ionotronic memory devices based on WS2 exhibit reverse hysteresis with memory windows larger than 25 V, and extinction ratio greater than 106. The mem-transistors show stable retention and endurance greater than 100 sweep cycles and 400 pulse cycles in addition to 6-bit (64 distinct nonvolatile storage levels) pulse-programmable memory features ranging over six orders of current magnitudes (10−12–10−6 A). The origin of the multi-bit states is attributed to the carrier dynamics under electrostatic doping fluctuations induced by mobile ions, which is illustrated by employing a fingerprint mechanism including band-bending pictures. The credibility of all the storage states is confirmed by obtaining reliable signal-to-noise ratios. We also demonstrate key neuromorphic behaviors, such as synaptic plasticity, near linear potentiation, and depression, rendering it suitable for successful implementation in high temperature neuromorphic computing. Furthermore, artificial neural network simulations based on the conductance weight update characteristics of the proposed ionotronic mem-transistors are performed to explore the potency for accurate image recognition. Our findings showcase a different class of thermally aided memories based on 2D semiconductors unlocking promising avenues for high temperature memory applications in demanding electronics and forthcoming neuromorphic computing technologies. [ABSTRACT FROM AUTHOR]

In this article, we report dielectric behavior and current–voltage characteristics of manganese (Mn)-doped zirconia nanocomposite in the 298 < T < 523 K temperature range. It is observed that the electrical response is controlled by the Mn concentration present in the sample. Both ac and dc conductivities of the prepared samples are observed to increase as the temperature rises. This suggests that the prepared samples behave in a semiconducting nature. Also, the ac conductivities of the samples increase with the frequency, which is prominent beyond the hopping frequency. The complex dielectric permittivity decreases with frequency and attains saturation at high-frequency regions. The current–voltage study shows that trap height increases with temperature and sample behavior is governed by the Poole Frenkel Emission model. [ABSTRACT FROM AUTHOR]

In this study, the impact of Nd doping on the structural, microstructural, dielectric, ferroelectric, and transport properties of Pb (1 - x) Nd x (Fe 0.5 Nb 0.5) 1 - x / 4 O 3 (PNFN) solid solutions ( x = 0 , 0.02 , 0.04 , 0.08 , and 0.1 ) is reported. For all the solid solutions, room temperature Rietveld refined X-ray diffraction (XRD) analysis reveals the monoclinic crystal structure with Cm space group. From Field emission scanning electron microscope (FESEM) studies, the polyhedral-shaped grains are found to be homogeneously distributed. Variation of dielectric properties with temperature displays the decrease of phase transition temperature (TC) with increasing Nd content. The temperature-dependent AC conductivity follows the Arrhenius behavior and the activation energies are calculated for high temperature regions. The frequency dependent AC conductivity behavior obeys the Johnscher's power law. Impedance spectroscopy results show the impact of conductivity from the bulk (grain) and displays non-Debye type of behaviour. Electric modulus demonstrates thermally activated relaxation phenomenon in the materials. Polarization vs. electric field (P-E) loops analysis confirms the ferroelectric nature of the materials. With increase in Nd concentrations, the value of remanent polarization (2Pr) increases, on the other hand, the coercive field (2Ec) value decreases. Both of these properties are suitable for enhancement of the physical properties of the multiferroic materials. [ABSTRACT FROM AUTHOR]

Tidal inlet, a fragile coastal feature along the world coastline, provides a range of ecosystem services and societal values. In recent decades, these systems are subjected to natural and anthropogenic pressure resulting in inlet choking and relocation, changing geomorphology, and dysfunction of physio-biological processes and loss of productivity of coastal water bodies. In this study, an assessment of the Chilika tidal inlet has been carried out using observation and modeling approach. The hydrodynamics of tide and its propagation along the inlet channel is studied using a two-dimensional depth-averaged hydrodynamic numerical model (MIKE 21). The model simulation was performed forcing tide and river discharge at land and ocean boundary and the model is validated with tide measured along the inlet channel. Tidal propagation under various inlet configuration was studied conducting two different simulations, which are, (a) natural inlet configuration (simulation-1) and (b) excluding islands from inlet channel (simulation-2). Besides, stability analysis of inlet is carried out using an empirical model (CEA model) with different inlet characteristics. Hydrodynamic model results show that tidal inlet is dominated with flood tidal asymmetry and tide gets distorted more during its propagation into the shallower region. The magnitude of tidal asymmetry varies from 0 to 0.13 with maximum distortion under exclusion of islands from inlet channel compared to natural inlet configuration. As a measure of inlet stability, unstable, stable, and critical cross-sectional areas (CSA) of inlet, which determine the functionality of inlet system, were evaluated from August 2011 to September 2013. The model estimated unstable CSA is found in close agreement with the observed inlet CSA and far away from the stable CSA indicating instability behavior of the inlet system. Projections of inlet stability under different conditions, viz. inlet length, inlet width, and bottom roughness, show varying channel length increases of stable and unstable CSA in accordance with increase in inlet length, while inlet stability varies inversely with increase in inlet width and friction, respectively. This study is helpful for planning, management, and development of the Chilika inlet for appropriate lagoon-sea interaction while dredging sand materials from inlet channel. [ABSTRACT FROM AUTHOR]

The central west coast of India comprises the 720 km long coastline of Maharashtra state and houses widespread industrial zones along the eastern Arabian Sea. Sediments from seven industrial-dominated estuaries along the central west coast were studied for metal enrichment and benthic assemblages to determine sediment quality status and ecological effects in these areas. The suit of geochemical indices highlighted the contamination of sediment in the estuaries concerning heavy metals. Positive correlations of Hg with Co, Zn, Ni, Cr, and Pb indicated the source similarity and effect of anthropogenic activity. non-Metric Multidimensional Scaling (n-MDS) based on meiofaunal abundance showed a cleared separation of clusters through the gradient of heavy metal concentrations. The Canonical Correspondence Analysis (CCA) results with the Monte Carlo test signified those heavy metals influenced the meiobenthic community. Heavy metals (Cr, Ni, Zn, Cd, Pb, and Hg) were the main drivers shaping the meiofaunal community with a significant (p < 0.05) reduction in taxa richness, diversity, and evenness. Dominant meiofaunal assemblages evidence the tolerance of foraminiferans and nematodes. However, these taxa were affected by decreased abundance at impacted sites compared to other fauna. In conclusion, results demonstrated that impairment occurred in the meiofaunal community in most estuaries (except AB and KK). [ABSTRACT FROM AUTHOR]

The single-phase (HfxZr0.8−x) (Ta0.1Dy0.1) O2 with 0.2 ≤ x ≤ 0.6 ceramics were synthesized by conventional solid-state reaction. The structural and morphological/microstructural characteristics were studied using x-ray diffraction and scanning electron microscopy, respectively. The dielectric properties and electrical conductivity of the bulk material were investigated as a function of temperature and frequency in the metal–insulator–metal configuration. The room-temperature dielectric constant at 100 kHz was found to be in the range of 17–35, along with low dielectric loss < 0.02. The leakage current densities at 3 kV/cm were 3.085 × 10−5, 1.67 × 10−5, and 3.93 × 10−6 A/cm2 for (Hf0.2Zr0.6)(Ta0.1, Dy0.1) O2, (Hf0.4Zr0.4)(Ta0.1, Dy0.1)O2, and (Hf0.6Zr0.2)(Ta0.1Dy0.1)O2, respectively. The frequency dependence of ac conductivity obeyed the Jonscher power law, suggesting hopping-based conduction. [ABSTRACT FROM AUTHOR]

The removal of linear alkylbenzene sulfonate (LAS) from river water was investigated using laboratory batch and column adsorption experiments to simulate and characterize critical geoenvironmental factors during riverbank filtration (RBF), including fine content, grain size (d50) of aquifer soil, soil bed depth, and detention time. The study examined nine distinct types of aquifer soil. Pseudo-1st-order, pseudo-2nd-order, and intra-particle diffusion kinetic equations were used to examine the kinetic data. The adsorption kinetics were found to be consistent with all kinetic models (R2 > 0.9). For each of the nine adsorbents, a column study was conducted and the logit method was used to calculate the different associated parameters. The assessment of efficacy under varying experimental conditions of empty bed contact time (EBCT) and bed depth, revealed that, an increase in EBCT and bed depth resulted in increased exhaustion time. From both batch and column kinetic study, it can be observed that rate of adsorption is higher for soil having highest fine content as well as for soil having smaller particle sizes. According to field data collected at three river bank filtration sites, the removal of LAS ranged between 44 and 88%, depending on the geoenvironmental factors' aquifer conditions and the season of study. The study established the critical role of geoenvironmental factors in LAS adsorption, which will aid in the identification of suitable aquifer site conditions for the new RBF system. [ABSTRACT FROM AUTHOR]

In this study, silicon carbide mixed electrical discharge machining (SCMEDM) process has been developed and later on modelled also using an artificial neural network (ANN) based technique as well as response surface methodology (RSM). Experiments were conducted with Al LM-25/SiC metal matrix composites as per Box Behnken design (BBD). Discharge current, pulse-on-time, servo-voltage, powder concentration, tool material and varying reinforcement levels were considered as machining input parameters. Material removal rate, tool wear rate and surface roughness were taken to be the response parameters. Analysis of variance (ANOVA) method was used to investigate the significant effect of parameters on the response measures. The experimental data was trained using a back-propagation ANN technique. Research shows that the influence of current, pulse length and tool material on the machining characteristics of Al LM-25 MMCs is significant. Surrogated models were also developed for proposed process using RSM. However, the accuracy of ANN models was found to be better than that of RSM models. [ABSTRACT FROM AUTHOR]

Heat shock transcription factors (Hsfs) play an essential role as transcriptional regulatory proteins against heat stress by controlling the expression of heat-responsive genes. Common bean is a highly thermosensitive crop, and, therefore, its genome sequence information is segregated, characterized here in terms of heat shock transcription factors and its evolutionary significance. In this study, a complete comprehensive set of 29 non-redundant full-length Hsf genes were identified and characterized from Phaseolus vulgaris L. (PvHsf) genome sequence. Detailed gene information such as chromosomal localization, domain position, motif organization, and exon–intron identification were analyzed. All the 29 PvHsf genes were mapped on 8 out of 11 chromosomes, indicating the gene duplication occurred in the common bean genome. Motif analysis and exon–intron structure were conserved in each group, which showed that the cytoplasmic proteins highly influence the conserved structure of PvHsfs and heat-induced response. The HSF genes were grouped into three classes, i.e., A to C and 14 groups, based on structural features and phylogenetic relationships. Only one pair of paralog sequences suggests that it may be derived from the duplication event during evolution. A comparative genomics study indicated the influence of whole-genome duplication and purifying selection on the common bean genome during development. In silico expression analysis showed the active role of class A and B family during abiotic stress conditions and higher expression in floral organs. The qRT-PCR analysis revealed PvHSFA8 as the master regulator and PvHSFB1A and PvHSFB2A induction during heat exposure in French beans. [ABSTRACT FROM AUTHOR]

Cryptochrome 2 (CRY2) perceives blue/UV-A light and regulates photomorphogenesis in plants. However, besides Arabidopsis, CRY2 has been functionally characterized only in native species of japonica rice and tomato. In the present study, the BnCRY2a, generating a relatively longer cDNA and harboring an intron in its 5′UTR, has been characterized in detail. Western blot analysis revealed that BnCRY2a is light labile and degraded rapidly by 26S proteasome when seedlings are irradiated with blue light. For functional analysis, BnCRY2a was over-expressed in Brassicajuncea, a related species more amenable to transformation. The BnCRY2a over-expression (BnCRY2aOE) transgenics developed short hypocotyl and expanded cotyledons, accumulated more anthocyanin in light-grown seedlings, and displayed early flowering on maturity. Early flowering in BnCRY2aOE transgenics was coupled with the up-regulation of many flowering-related genes such as FT. The present study also highlights the differential light sensitivity of cry1 and cry2 in controlling hypocotyl elongation growth in Brassica. BnCRY2aOE seedlings developed much shorter hypocotyl under the low-intensity of blue light, while BnCRY1OE seedling hypocotyls were shorter under the high-intensity blue light, compared to untransformed seedlings. Key message: Brassica napus (2n = 38, AACC) is an allotetraploid derived from cross-hybridization of B. rapa (2n = 20, AA) and B. oleracea (2n = 18, CC), followed by chromosome doubling. It is an important oilseed crop, and therefore, efforts are being made to enhance its agronomic traits. Early flowering is one of the essential agronomic traits which the breeders have long targeted in order to shorten the life cycle of Brassica. Early flowering along with delayed maturity, and high leaf area index lead to increase in seed yield. Due to the problem of global warming, high temperature during the terminal stage of a crop can result in significant yield loss as high temperature has a negative effect on bud formation to silique development stage. In this research article, we have reported that overexpression of BnCRY2a in Brassica juncea results in early flowering. This opens the door for making early flowering variety of Brassica napus a reality without any yield penalty. In-depth analysis of the pathway BnCRY2a follows to cause early flowering phenotype will significantly enhance our knowledge on the mechanism of flowering in oilseed crop plants. [ABSTRACT FROM AUTHOR]

The recent COVID-19 outbreak highlighted the requirement for a more sophisticated healthcare system and real-time data analytics in the pandemic mitigation process. Moreover, real-time data plays a crucial role in the detection and alerting process. Combining smart healthcare systems with accurate real-time information about medical service availability, vaccination, and how the pandemic is spreading can directly affect the quality of life and economy. The existing architecture models are become inadequate in handling the pandemic mitigation process using real-time data. The present models are server-centric and controlled by a single party, where the management of confidentiality, integrity, and availability (CIA) of data is doubtful. Therefore, a decentralised user-centric model is necessary, where the CIA of user data is assured. In this paper, we have suggested a decentralized blockchain-based pandemic detection and assistance system (iBlock). The iBlock uses robust technologies like hybrid computing and IPFS to support system functionality. A pseudo-anonymous personal identity is introduced using H-PCS and cryptography for anonymous data sharing. The distributed data management module guarantees data CIA, security, and privacy using cryptography mechanisms. Furthermore, it delivers useful intelligent information in the form of suggestions and alerts to assist the users. Finally, the iBlock reduces stress on healthcare infrastructure and workers by providing accurate predictions and early warnings using AI/ML. [ABSTRACT FROM AUTHOR]

Multiferroic composites are promising candidates for magnetic field sensors, next-generation low power memory and spintronic devices, as they exhibit much higher magnetoelectric (ME) coupling and coupled ordering parameters compared to the single-phase multiferroics. Hence, the 3-0 type particulate multiferroic composites having general formula (1 − Φ)[PbFe0.5Nb0.5O3]-Φ[Co0.6Zn0.4Fe1.7Mn0.3O4] (Φ = 0.0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, (1 − Φ) PFN-ΦCZFMO) were prepared using a hybrid synthesis technique. Preliminary structural and microstructural analysis were carried out using XRD and FESEM techniques, which suggest the formation of 3-0 type particulate composite without the presence of any impurity phases. The multiferroic behaviour of the composites is studied with polarization versus electric field (P-E) and magnetization versus magnetic field (M-H) characteristics at room temperature. The nature of ME coupling was investigated elaborately by employing the Landau free energy equation along with the magneto-capacitance measurement. This investigation suggests the existence of biquadratic nature of ME coupling (P2M2). The magneto-electric coupling measurement also suggests that strain mediated domain coupling between the ferroelectric and magnetic ordering is responsible for the magneto-electric behaviour. The obtained value of direct ME coefficient 26.78 mV/cm-Oe for Φ = 0.3, found to be higher than the well-known single-phase materials and polycrystalline composites. [ABSTRACT FROM AUTHOR]

One of the ways to mitigate the world energy crisis is to harvest clean and green energy from waste-heat, which is abundant, ubiquitous, and free. Energy harvesting of this waste-heat is one of the most encouraging methods to capture freely accessible electrical energy. Ferroelectric materials can be used to harvest energy for low power electronic devices, as they exhibit switchable polarization, excellent piezoelectric and pyroelectric properties. The most important characteristic of ferroelectric materials, in the context of energy harvesting, is their ability to generate electric power from a time-dependent temperature change. In this work, we grew highly c-axis oriented heterostructures of BaZr0.2Ti0.8O3 (barium zirconium titanate, BZT)/Ba0.7Ca0.3TiO3 (barium calcium titanate, BCT) on SrRuO3 (strontium ruthenate, SRO) and deposited on SrTiO3 (strontium titanate, STO) single crystalline substrate using pulsed laser deposition (PLD) technique. We investigated the structural, electrical, dielectric, and pyroelectric properties of the above-mentioned fabricated heterostructures. The wide range of θ–2θ X-ray diffraction (XRD) patterns only shows (00l) reflection peaks of heterostructures and the substrate which confirmed that the films are highly c-axis oriented. We are also capable to convert the low-grade waste-heat into electrical energy by measuring various temperature-dependent ferroelectric hysteresis loops of our nanostructure films via pyroelectric Ericsson cycles and the structures show an energy conversion density ~ 10,970 kJ/m3 per cycle. These devices exhibit a large pyroelectric current density of ~ 25 mA/m2 with 11.8 °C of temperature fluctuation and the corresponding pyroelectric coefficient of 3425 μC/m2K. Our research findings suggest that these lead-free relaxor-ferroelectric heterostructures might be the potential candidates to harvest electrical energy from waste low-grade thermal energy. [ABSTRACT FROM AUTHOR]

Coastal erosion is a major concern and a threat to the coastal habitats, livelihood and socio-economic developments. The aims of the present research are to investigate the beach dynamics, status, and protection measures of world famous nesting habitat near Rushikulya estuary, south Odisha coast, India. Shoreline mapping and rate of changes for a period of 8 years (2005–2013) on each side of the inlet, 3-year beach profile study at six transects, and 2 years (2009 and 2010) of sediment texture studies along with coastal processes provide a clear glance of the nesting beach health. The nesting beach changes observed were significant erosion (47–126 m) with northward growth of sand spit and deposition at the beach due to deformation of spit. From 2008 to 2011, the southern part of the beach experienced high erosion, while the northern part is under erosion and deposition with seasons. Medium sand predominated along the beach, while the foreshore zone at the northern part has fine sand along with sediment accumulation during the northeast monsoon period. Annual changes in wave pattern and reversal wind and current conditions make beach cyclic at the northern part of the nesting beach, while the status of the southern part of the beach depends upon the inlet shifting and human intervention on sand spit situated at the south of Rushikulya estuary. To avoid chronic erosion at the nesting beach, the sand spit needs to be cut from the mainland through regular monitoring of beach. The present study may help to prepare a framework for proper management and conservation of nesting habitat. [ABSTRACT FROM AUTHOR]

This work demonstrates the graphene oxide (GO) RRAM exhibiting low-power, low-voltage multilevel resistive switching when clamped to an oxygen vacancy rich bismuth ferrite (BFO) thin film. The GO/BFO structure also shows stable endurance characteristics with a larger memory window due to the accumulation of excess oxygen vacancies. The conduction process in pristine GO does not suffer larger distortion when it is stacked to BFO and follows Ohmic and trap-assisted space charge limited current conduction mechanism. In GO RRAM, Ag+ ion-induced conducting filament is primarily responsible for the switching process, while oxygen vacancies are dominating in bilayer device. The GO/BFO exhibits intermediate resistive states during the RESET process due to multiple breakdowns of conducting paths. At least a 4-bit multistate data storage configuration is demonstrated by tuning the pulse-amplitude of RESET from 2 to 5 V at a constant SET voltage of − 3 V. Thereafter, a 3-bit multilevel storage device can be configured in GO/BFO by tuning the pulse-width from 10 to 30 µs, which takes place at lower time scale than the BFO. Our findings suggest the possibility of ultrafast, multilevel RRAM for next-generation high-density memories and neuromorphic computing applications. [ABSTRACT FROM AUTHOR]

The drawbacks of common anodes in lithium-ion batteries (LIBs) and hybrid supercapacitors (HSCs), such as the high voltage plateau of Li4Ti5O12 (1.55 V vs. Li/Li+) and the moderate capacity of graphite (372 mAh-g-1), have established a need for better materials. Conversion materials, and in particular iron oxide and CaFe2O4 (CFO), have amassed recent attention as potential anode replacements. In this study, we evaluate the material and electrochemical effects of the solution combustion synthesis (SCS) of porous CFO across novel fuel-to-oxidizer ratios and calcination temperatures. We demonstrate that nearly doubling the amount of fuel used during synthesis increases capacities between 120 and 150% at high current densities (~ 1000 mA-g-1) and across 500 additional charging-discharging cycles, an effect brought on in part by enhanced compositional purity in these samples. However, in order to ensure long-term cyclic stability, it is necessary to also calcine porous CFO to 900 °C to enhance crystallite size, particle size and spacing, and compositional purity. [ABSTRACT FROM AUTHOR]

The effect of Sm doping on structural, dielectric, multiferroic and electrical properties of GaFeO3 with composition GaFe1-xSmxO3 (x = 0, 0.05, 0.10, 0.15) is studied. Rietveld refinement of the XRD data reveals the formation of single-phase orthorhombic structure. It is observed that the unit cell volume increases with rise in Sm content. FESEM study reveals that the irregular-shaped grains are uniformly distributed throughout the surface. From dielectric plot, a significant variation in εr and tanδ with Sm content is observed. Further, conjugate existence of both ferroelectric and magnetic ordering is confirmed by polarisation and magnetization hysteresis loop measurement. The remanent polarisation (Pr) is decreased with Sm content due to the defects related to fluctuations in the valance of Fe in the studied samples. Also, the remanent magnetization (Mr) is found to fall with rise in Sm content due to the lower magnetic moment (μ) of Sm3+. Impedance analysis shows the existence of two types of relaxation in studied materials. [ABSTRACT FROM AUTHOR]

Raman scattering and ab initio Raman/phonon calculations, supported by X-ray diffraction, are combined to study the vibrational properties of Zn1−xBexTe under pressure. The dependence of the Be–Te (distinct) and Zn–Te (compact) Raman doublets that distinguish between Be- and Zn-like environments is examined within the percolation model with special attention to x ~ (0,1). The Be-like environment hardens faster than the Zn-like one under pressure, resulting in the two sub-modes per doublet getting closer and mechanically coupled. When a bond is so dominant that it forms a matrix-like continuum, its two submodes freely couple on crossing at the resonance, with an effective transfer of oscillator strength. Post resonance the two submodes stabilize into an inverted doublet shifted in block under pressure. When a bond achieves lower content and merely self-connects via (finite/infinite) treelike chains, the coupling is undermined by overdamping of the in-chain stretching until a «phonon exceptional point» is reached at the resonance. Only the out-of-chain vibrations «survive» the resonance, the in-chain ones are «killed». This picture is not bond-related, and hence presumably generic to mixed crystals of the closing-type under pressure (dominant over the opening-type), indicating a key role of the mesostructure in the pressure dependence of phonons in mixed crystals. [ABSTRACT FROM AUTHOR]

Ferroelectric ceramic–polymer composites consisting of Poly Vinyledine Fluoride–Hexa Fluoro Propylene (PVDF-HFP) as polymer host and 0.5Ba(Zr0.2Ti0.8)O3−0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) ceramics as filler were prepared using solution casting technique. These composites are characterized for structural, microstructural, vibrational, optical, dielectric and ferroelectric properties at various experimental conditions. The electroactive β phase fraction (observed from XRD and FTIR analysis) increases as the filler concentration increases up to 20 wt% of BZT-BCT and above that its value decreases. FTIR results were analyzed to understand the mechanism of enhancement of β phase by the interaction between negatively surface charged ions of filler with the CH2 dipole of polymer matrix. UV–visible spectroscopy also employed to confirm polymer–ceramic filler interaction. Variation of the dielectric constant with different filler concentrations is explained using the percolation theory. Finally, the interplay between the functional properties and the β phase is discussed in detail. [ABSTRACT FROM AUTHOR]

High water absorption capacity and low biodegradation of fiber reinforced composites are the major drawbacks, which limit their applications in different sectors. Development of composites with complete biodegradability is challenging as biodegradability may be incomplete by lowering of its water adsorption capacity. In this work, a series of thermoplastic starch (TPS) reinforced jute (10–40 wt%) composites were developed by compression molding and measured by their mechanical properties. The composite with 30% jute showed the maximum tensile strength (27.3 MPa). Contact angle, and water absorption measurements exposed that composites are moderately hydrophobic in nature. Both soil burial and fungal degradation testing showed biodegradability of composites. Characterizations of optimized composite before and after biodegradation test, were carried out by FTIR, SEM and optical microscope. The present study showed promise on feasible applications of jute-starch composites in packaging, automobile sector, cutlery, indoor furnishing, etc. as a substitute of plastic-based composites. [ABSTRACT FROM AUTHOR]

In traditional practices, detection of rice plant diseases by experts is a subjective matter whereas by testing in the laboratory is time-consuming. As a consequence, it causes reduction on agricultural production and economic loss to farmers. To overcome this, there is a demand to develop fast and effective systems to detect and classify rice plant diseases. Therefore, the development of image-based automated systems for classification of rice plant diseases is an interesting growing research area in the agriculture domain. Color is one of the important features to classify rice plant diseases. In this study, we have presented an image-based rice plant disease classification approach using color features only. We have explored 14 different color spaces and extracted four features from each color channel leading to 172 features. Moreover, the performance of seven different classifiers have been compared and demonstrated that a highest classification accuracy of 94.65% has been achieved using support vector machine (SVM) classifier. Training and testing of models were performed on the dataset that consists of 619 images. This dataset was collected from the real agriculture field that belongs to four classes: (a) Bacterial Leaf Blight (BLB), (b) Rice Blast (RB), (c) Sheath Blight (SB) and (d) Healthy Leave (HL). The encouraging results of this paper show that color features can play an important role in developing rice plant disease classification system and enable the farmers to take preventive measures resulting in better product quality and quantity. [ABSTRACT FROM AUTHOR]

Research highlights: Sensitivity of initial and boundary conditions (ICs) are studied for an extra-tropical cyclone (ETC, Gong (2013)) over North Atlantic Ocean using WRF model. Movement (track) and synoptic feature of Gong have been evaluated with observations. WRF could simulate the characteristics throughout life cycle of Gong. The model attained intense stage was well simulated. Cyclogenesis and Q-Vector for Gong are sensitive to the ICs and model could simulate better with 48-h lead time. The role of initial conditions (ICs) in the simulation of severe winter storm 'Gong' formed over North Atlantic is studied. The life cycle of Gong started at 1800 UTC of 16–0600 UTC of 22 January, 2013, with CSLP of 972 hPa. The gusty wind (~33 ms−1) and torrential rainfall of ~90 mm d−1 recorded over several major cities of the Iberian peninsula. Five numerical experiments were performed with the WRF model by initializing at 0600 UTC of 16, 1800 UTC of 16, 0600 UTC of 17, 1800 UTC of 17, and 0600 UTC of 18 January, 2013. Our results suggest that significant differences are seen among the experiments, particularly with the ICs of 0600 UTC 17 January, 2013, which represent the quick movement of Gong with a slight underestimation of intensity. The experiment with IC 0600 UTC on 18 January, 2013 produced the best simulation as compared to the observations. The simulated track, intensity, wind flow, and rainfall were well agreeing with the observations. The 12-h average track errors were ranging from 95 to 332 km with 24-, 36-, 48-, 60-, and 72-h lead time. The Q-vectors of Gong with the WRF model with 24-h lead time produced minimum errors. [ABSTRACT FROM AUTHOR]

This work reports on the dielectric and electrical properties of a single-phase polycrystalline pyrochlore structured Gd2Zr2O7 ceramics with a highly dense and compact microstructure. X-ray diffraction along with Raman spectroscopic studies confirmed the formation of the pyrochlore phase; while the electron microscopy investigations showed the uniformly distributed and densely packed micrometer-sized grains. The relaxation phenomena and conduction processes in Gd2Zr2O7 analyzed using complex impedance spectroscopy which showed the appearance of low-frequency dielectric dispersion suggesting the dominance of conduction by oxygen ions. Observation of double semi-circular arcs in the Nyquist plots confirms that both grains and grain boundaries contribute to the electrical impedance of Gd2Zr2O7. The temperature-dependent ac conductivity studies on Gd2Zr2O7 followed the Jonscher's power law exhibited a strong dispersive behavior at the low temperature (< 300 °C) over the whole frequency region; whereas a weak dispersive nature observed at the higher temperature in the higher frequency region. An enhanced conductivity with relaxation phenomenon at elevated temperature is attributed to the transition from prolonged hopping to short-range ionic transportation. The increase in the ac conductivity with temperature reveals that Gd2Zr2O7 pyrochlore has a negative coefficient of resistance. Because of the good control of the electrical transport properties of Gd2Zr2O7 ceramic on its structure, it could be further exploited for the development of advanced solid-electrolytes for solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

This study examines credit constraints using standard models in the highly constrained micro, small, and medium enterprises (MSMEs) sector in India. The mixed results may not be reflective of MSMEs in India, as the standard models have been developed for much larger firms in western markets having lower information asymmetry than Indian firms. These models are biased toward long-term financing due to the ready availability of short-term credit in western markets, as against limited access to working capital to MSMEs in India. We propose an augmented model of investment sensitivity based on the framework of the Fazzari and Petersen model and Carpenter and Petersen model that includes the often-neglected role of working capital as both a use and a source of funds, and gross fixed asset formation and leverage as drivers of credit constraints, for the information asymmetric MSME firms. The paper finds the augmented model, also called the Financing Deficit Model, robust for ascertaining credit constraints of Indian MSME firms and its variables consistent with available literature. [ABSTRACT FROM AUTHOR]

The generic 1-bond → 2-mode "percolation-type" Raman signal inherent to the short bond of common A1−xBxC semiconductor mixed crystals with zincblende (cubic) structure is exploited as a sensitive "mesoscope" to explore how various ZnSe-based systems engage their pressure-induced structural transition (to rock-salt) at the sub-macroscopic scale—with a focus on Zn1−xCdxSe. The Raman doublet, that distinguishes between the AC- and BC-like environments of the short bond, is reactive to pressure: either it closes (Zn1−xBexSe, ZnSe1−xSx) or it opens (Zn1−xCdxSe), depending on the hardening rates of the two environments under pressure. A partition of II–VI and III–V mixed crystals is accordingly outlined. Of special interest is the "closure" case, in which the system resonantly stabilizes ante transition at its "exceptional point" corresponding to a virtual decoupling, by overdamping, of the two oscillators forming the Raman doublet. At this limit, the chain-connected bonds of the short species (taken as the minor one) freeze along the chain into a rigid backbone. This reveals a capacity behind alloying to reduce the thermal conductivity as well as the thermalization rate of photo-generated electrons. [ABSTRACT FROM AUTHOR]

Availability of electrical power round the clock and throughout the year is essential for industrial and economic growth of any country. The present era of fierce competition harnessed with financial constraints brought in the concepts of reliability and availability to necessitate continuity in power generation process. Reliability of a whole power plant depends upon the reliability of its individual equipments and machines. Turbine is the most important and complex equipment in a thermal power plant. A steam turbine extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft, which in turn is coupled with a generator to produce electricity. Though there are various modes of the imperfection in a turbine, undesirable LPDE (low-pressure differential expansion) is one of those. In this experimental work, the root cause failure analysis is done for the undesired LPDE of a turbine, to explore the various reasons of it. The necessary rectification has been made to eliminate higher LPDE, and the performance of the turbine has been enhanced. [ABSTRACT FROM AUTHOR]

Tumor metastasis comprises a series of coordinated events that culminate in dissemination of cancer cells to distant sites within the body representing the greatest challenge impeding effective therapy of cancer and the leading cause of cancer-associated morbidity. Cancer cells exploit multiple genes and pathways to colonize to distant organs. These pathways are integrated and regulated at different levels by cellular- and extracellular-associated factors. Defining the genes and pathways that govern metastasis can provide new targets for therapeutic intervention. Melanoma differentiation associated gene-9 (mda-9) (also known as Syntenin-1 and SDCBP (Syndecan binding protein)) was identified by subtraction hybridization as a novel gene displaying differential temporal expression during differentiation of melanoma. MDA-9/Syntenin is an established Syndecan binding protein that functions as an adaptor protein. Expression of MDA-9/Syntenin is elevated at an RNA and protein level in a wide-range of cancers including melanoma, glioblastoma, neuroblastoma, and prostate, breast and liver cancer. Expression is increased significantly in metastatic cancer cells as compared with non-metastatic cancer cells or normal cells, which make it an attractive target in treating cancer metastasis. In this review, we focus on the role and regulation of mda-9 in cancer progression and metastasis. [ABSTRACT FROM AUTHOR]

Kanchankayi is located in the central part of the 55 km long Kurlagere-Gogi-Gundanahalli (KG) fault of Meso-Neoproterozoic Bhima basin of Southern India. Intensive integrated exploration in Kanchankayi has established a concealed, fracture-controlled, low-grade uranium deposit. Uranium mineralisation is mostly confined within the fractured limestone of Shahabad Formation and partly within fractured basement granite. Tectonic movements along the KG fault in Kanchankayi area have resulted in the northward thrusting of basement granite over the Bhima sediments forming a reverse fault geometry. Structural mapping and subsurface exploration has established that the uranium mineralisation is mainly confined to the fault zone. In general, the fault zone is characterised by steep southerly dipping to vertical limestone beds. Iso-dip contouring was attempted on the beds having equal angle of dip, with the premise that steep southerly dipping and vertical beds will reveal the trend and location of the fault zone on the surface. The iso-dip contour map reveals that the contour depicting the fault zone initially follows the basement-sediment contact and further NE i.e. towards Kanchankayi and transgresses into the Bhima sediments. This suggests that the fault zone, instead of following the basement-sediment contact, moves within the basin in Kanchankayi. Recent sub-surface exploration in Kanchankayi has corroborated this interpretation. The innovative approach in utilizing structural mapping and iso-dip contouring has not only given a new dimension to the exploration programme at Kanchankayi but also provided a model technique for exploration of concealed, structure-controlled, hydrothermal, vein-type uranium mineralisation in parts of Bhima basin. [ABSTRACT FROM AUTHOR]

This paper presents new data on natural environmental radiation mapping in Meghalaya for the first time in India. Two alternate methods have been used to map (1) a regional low-density environmental radiation mapping by using radiation meters, (2) high-resolution radiation mapping of Shillong Basin using the data generated by an integrated litho- and pedo-geochemical sampling program using gamma ray spectrometric measurements on both rock and soils samples. The variation in radio-elemental concentrations and radiation levels are related to bedrock geology and structures. The high levels of radiation levels are observed in the areas occupied by Mylliem Granite (3.935 mSv/a, 51 μR/h, 178.066 nGy/s) followed by South Khasi Batholith with pink feldspar (2.42 to 3.652 mSv/a, 31 μR/h, 109.502–165.249 nGy/s), graphitic schists (avg. 52.10 pGy/s, 1.06 mSv/a), Chlorite Schist (avg. 51.16 pGy/s, 1.13 mSv/a), Phyllites (avg. 47.98 pGy/s, 1.06 mSv/a), volcanics (avg. 46.9 pGy/s, 1.04 mSv/a), The Chlorite schist of Tyrsad formation (21 μR/h, 1.643 mSv/a, 74.321 nGy/s) and Barapani arenite (16 μR/h 1.21 mSv/a, 54.773 nGy/s), Tertiary sandstone (21 μR/h, 1.633 mSv/a, 73.885 nGy/s), Shella subgroup (12 μR/h, 0.914 mSv/a, 41.376 nGy/s), Langpars (13 μR/h, 1.006 mSv/a, 45.502 nGy/s), Upper Mahadek (26 μR/h, 2.062 mSv/a, 93.298 nGy/s), Lower Mahadek (38 μR/h, 2.935 mSv/a, 132.785 nGy/s), and the lowest environmental radiation levels are observed over Sylhet traps (9 μR/h, 0.725 mSv/a, 32.786 nGy/s). The soils generally show higher radiation levels as compared to their bed rocks. Comparisons are made with high radiation areas of the world results, showing that they are lower than high background radiation areas. These radiation images are the first series of environmental images for Meghalaya and will serve as the baseline data for the upcoming uranium mining projects in Meghalaya. Baseline environmental radiation images are necessary information to policy makers and provide a sound basis for addressing the public concerns for radiation levels. [ABSTRACT FROM AUTHOR]

Simultaneous effects of Na and Mn co-dopants on either site of LaFeO3 on the structural, magnetic, and low-temperature dielectric properties are studied in detail. The nanoparticles are prepared using a modified wet chemical route. The X-ray diffraction pattern is consistent with the formation of monophase with the distorted orthorhombic crystal structure. The average particle size is measured to be around 34 nm. The temperature and field dependent magnetization data reveals a drastic magnetic phase change of the modified co-doping system than LaFeO3 which is otherwise canted antiferromagnetic. This phase change is attributed to the mixed valence state of Mn ions present in the system due to substitutions. Several orders of change in the dielectric order parameter are found in the doped system. The low-temperature impedance spectra of the doped samples show dominant grain boundary relaxation as evidenced by modulus spectra. The conduction mechanism has been identified by calculating activation energies of relaxation from grain boundary and grain resistances as well as from ac conductivity analysis which are in good agreement. The typical calculated values are evidence of small polaronic hopping conduction mechanism in the sample. [ABSTRACT FROM AUTHOR]

In the recent years, there is a trend to build super thermal power plants in order to have better economic viability. With the growth of the capacity and size, the complexities of these plants have also grown multifold. There is more chance of fault in the system, when it is more complex. An early detection of these faults can allow time for preventive maintenance before a severe failure occurs. Condition monitoring is implementation of the advanced diagnostic techniques to reduce downtime and to increase the efficiency and reliability. The research is for determining the usage of advanced techniques like Vibration analysis and Oil analysis and to diagnose ensuing problems of the plant and machinery at an early stage and plan to take corrective and preventive actions to eliminate the issue and enhancing the reliability of the system. Now days, most of the industries have adopted the condition monitoring techniques as a part of support system to the basic maintenance strategies. Failure Mode, Effect and Criticality Analysis (FMECA) is associated with condition monitoring to determine the criticality of such unit or machines. It is a design method used to systematically analyze probable component failure modes of product or process, assess the risk associated with these failure modes and find out the resultant effects on system operations. In this study, practical approach have been applied for the FMECA to determine the critical equipments in a super thermal power plant and condition monitoring of such equipments have been done. [ABSTRACT FROM AUTHOR]

Accurate estimation of evapotranspiration is generally constrained due to lack of required hydrometeorological datasets. This study addresses the performance analysis of reference evapotranspiration (ETo) estimated from NASA/POWER, National Center for Environmental Prediction (NCEP) global reanalysis data before and after dynamical downscaling through the Weather Research and Forecasting (WRF) model. The state-of-the-art Hamon's and Penman-Monteith's methods were utilized for the ETo estimation in the Northern India. The performance indices such as bias, root mean square error (RMSE), and correlation (r) were calculated, which showed the values 0.242, 0.422, and 0.959 for NCEP data (without downscaling) and 0.230, 0.402, and 0.969 for the downscaled data respectively. The results indicated that after WRF downscaling, there was some marginal improvement found in the ETo as compared to the without downscaling datasets. However, a better performance was found in the case of NASA/POWER datasets with bias, RMSE, and correlation values of 0.154, 0.348, and 0.960 respectively. In overall, the results indicated that the NASA/POWER and WRF downscaled data can be used for ETo estimation, especially in the ungauged areas. However, NASA/POWER is recommended as the ETo calculations are less computationally expensive and easily available than performing WRF simulations. [ABSTRACT FROM AUTHOR]

Delineation of management zones (MZs) are needed to manage fields in order to maximize economic return, minimize environmental impact, and improve soil and crop management. The MZs of uniform production potential may offer an effective solution to nutrient management. In this study, a total of 122 geo-referenced representative surface (0–250 mm depth) soil samples were collected from the study area covering an area of 6296 ha. Soil samples were analysed for pH, EC, CaCO3, organic carbon (SOC), available nitrogen (AN), available phosphorus (AP), available potassium (AK) and micronutrients (Fe, Mn, Zn and Cu). Their spatial variability was analyzed and spatial distribution maps were constructed using geostatistical techniques. Geostatistical analysis showed that exponential, rational quadratic, tetraspherical, pentaspherical and circular models were the best-fit models for soil properties and available nutrients. Further, geographical weighted principal component analysis (GWPCA) and possibilistic fuzzy C-means (PFCM) clustering algorithm were carried out to delineate the management zones based on optimum clusters identified using fuzzy performance index (FPI) and normalized classification entropy (NCE). The results revealed that the optimum number of MZs for this study area was four and there was heterogeneity in soil nutrients in four MZs. The study indicated that MZ-based soil test crop response recommendation reduces the application quantity of fertilizer significantly at a large extent. Therefore, the management zone concept can reduce agricultural inputs and environmental pollution, and maximize crop production. [ABSTRACT FROM AUTHOR]

A series of phosphate based phosphors NaCd1−xPO4: xDy3+(x = 0.02–0.1) are prepared by adopting conventional solid state reaction routes. The prepared phosphors are well characterized by x-ray diffraction to establish the phase purity while a field emission scanning electron microscope is used to detect the microstructure. The surface chemical composition, an important aspect of this work, is established by x-ray photoelectron spectroscopy. The photoluminescence excitation spectra are recorded at room temperature, in which the excitation maxima are observed at 347 nm, indicating a near ultraviolet (UV) excitation which can be useful for light emitting diodes with a UV chip. The emission spectra show three major emission lines at 480 nm (4F9/2 → 6H15/2) a blue emission, a yellow emission around 570 nm (4F9/2 → 6H13/2) and a red emission around 662 nm (4F9/2 → 6H11/2). The CIE 1931 color chromaticity diagram shows the color coordinates around (0.32, 0.31) and such phosphors can be useful for solid state lighting applications as the emission spectrum lies in the near white region in the color space. [ABSTRACT FROM AUTHOR]

We demonstrate in detail the influence of divalent non-magnetic metal ion Zn on the structural, magnetic ordering as well as the dielectric dynamics of nano-sized LaFeO3. Introduction of Zn at Fe site distorts the FeO6 octahedron near it evidencing from a shift in the most intense peak towards lower angle. Subsequent broadening of peaks signifies a lower particle size which is further supported by micrographs. With field history, temperature-dependent magnetization shows that the doped samples acquire a non-ergodic state at low temperature and the incompleteness of the phase transition even at very high temperature. The isothermal magnetization depicts a significant increase in magnetization at higher field with a decrease in coercivity. Extensive impedance and electrical modulus analysis are carried out to know the exact conduction process and relaxation mechanism adopted by the doping system. Impedance spectra reveal a non-Debye type of relaxation mechanism and with increase of Zn concentration and temperature, grain boundary effect dominates over grain effect. This grain and grain boundary effect is further confirmed through electrical modulus Nyquist plots. The activation energy values of grain and grain boundary are 0.37 eV and 0.47 eV for x = 0.1, 0.37 eV, 0.40 eV for x = 0.2 and 0.28 eV, 0.38 eV for x = 0.3, respectively. Accordingly, the doping system agreed with a p-type polaronic hopping. Furthermore, the frequency-dependent electrical conductivity data are explained in the framework of both Jonscher power law and Jump relaxation model. [ABSTRACT FROM AUTHOR]

Combining two materials in a nanoscale level can create a composite with new functionalities and improvements in their physical and chemical properties. Here we present a high-throughput approach to produce a nanocomposite consisting of metal nanoparticles and semiconductor oxide nanostructures. Volmer-Weber growth, though unfavorable for thin films, promotes nucleation of dense and isolated metal nanoparticles on crystalline oxide nanostructures, resulting in new material properties. We demonstrate such a growth of Au nanoparticles on SnO2 nanostructures and a remarkable sensitivity of the nanocomposite for detecting traces of analytes in surface enhanced Raman spectroscopy. Au nanoparticles with tunable size enable us to modify surface wettability and convert hydrophilic oxide surfaces into super-hydrophobic with contact angles over 150°. We also find that charge injection through electron beam exposure shows the same effect as photo-induced charge separation, providing an extra Raman enhancement up to an order of magnitude. [ABSTRACT FROM AUTHOR]