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This study used zinc/iron acetate (as a precursor) and a carboxylic variant of activated carbon (as a matrix) to create nanostructured zinc ferrite (ZnFe2O4). Carboxylic derivative (AC–COOH) of activated carbon was obtained by nitric acid oxidation. Then, enhanced activated carbon's surface was impregnated with ZnFe2O4. ZnFe2O4 nanoparticles with a size range of 25–35 nm and a surface area of 165.8 m2g−1 were proven to have been achieved after the ZnFe2O4 nanostructure was characterized by XRD, FESEM, TEM, UV, PL, BET, and XPS. Using the same testing circumstances, the optimized photocatalyst with 10 wt.% ZnFe2O4 inserted AC demonstrated the best degrading efficeicny to methylene blue (99%) and Reactive red (94%). The Langmuir–Hinshelwood hypothesis, which states that the dye concentration is a first-order function of time, was validated by kinetic investigations. The photocatalyst was shown to be stable after 7 cycles of recycling under optimal circumstances in a study of the reusability of a 10-ZnFe2O4/AC photocatalyst. In addition, PL, TRPL, EIS, and transient-photocurrent response all provide strong evidence for the efficient charge separation in ZnFe2O4/AC. [ABSTRACT FROM AUTHOR]

Background: Leucorrhoea or vaginal discharge is one of the very common problem or complaint among female of reproductive age group (15-45) attending to Gynecology and Venereology outpatient department and it is associated with STI/HIV and adverse birth out comes. Objective of the study was isolation identification and to assess the frequency of occurrence of various microbial agents. Materials and Methods: Between July 2023 to December 2023, 125 sexually active women (15-45) age were enrolled from two reproductive health clinics (Gynecology and Venereology) in Government General Hospital, Guntur. The women underwent an interview followed by physical examination. Vaginal swabs are taken and processed for confirmatory diagnosis of Bacterial vaginosis, trichomonal vaginitis and candidal vulvo vaginitis. Results: Among the study group of 125 women, majority of women belongs to urban area (70.4%), low socio-economic group 66.4%, illiterates 62.4% and 21-30 years of age (27%). Among the study group 30.4% were having bacterial vaginosis, 22.4% have vulvo vaginal candidiasis, and 10.4% have vaginal trichomoniasis. Conclusion: Microbial infections of lower genital tract are very common in sexually active women in reproductive age group. Nonspecific vaginosis mostly associated with Gardenella vaginosis, specific vaginosis with Trichomonas vaginosis, candiasis are very frequent. These infections in pregnancy cause adverse birth outcomes. Early and proper diagnosis and timely treatment of infected women including sexual partners is essential in cases of vaginal infections which requires laboratory assistance. [ABSTRACT FROM AUTHOR]

Magnetoelectric one-dimensional Ba2Zn2Fe12O22–PbZr0.52Ti0.48O3 core–shell nanofibers for magnetic field sensor applications have been fabricated by using the sol–gel electrospinning technique. Their structural, functional, morphological, compositional, magnetic, dielectric, ferroelectric, and leakage current characteristics were extensively investigated at room temperature. In addition, their magnetoelectric and magnetodielectric properties were analyzed. The ability of the core–shell nanofibers to detect low-strength AC and DC magnetic fields was demonstrated by measuring the magnetoelectric voltage induced by the magnetic field. Additionally, the sensitivity of AC/DC field sensors, the linearity, accuracy, and hysteresis are discussed. The nanofibers exhibit a sensitivity of 730 V/T for the AC magnetic field and 650 V/T for the DC magnetic field at a resonance frequency of 8.3 kHz. The limit of detection and resolution of the AC and DC magnetic field sensors are also calculated and reported. As demonstrated through the experimental results, the Ba2Zn2Fe12O22–PbZr0.52Ti0.48O3 core–shell nanofibers are effective in detecting the DC and AC magnetic fields in millitesla and microtesla ranges at room temperature, respectively. [ABSTRACT FROM AUTHOR]

The foremost challenge of rainfall forecasting is the intensity of rainfall in some particular stations. The unpredictable rainfall volume owing to the climate transformation can root cause for either overflow or dryness in the reservoir. In this article, we coin a novel model to predict the monthly rainfall by using an Ensemble Radial basis function Network and a One-Dimensional Deep Convolutional Neural Network algorithm. In the first step, nine climatological parameters, which are highly related to monthly rainfall disparity, are given as input for an ensemble model. In the second step, a hybrid approach is proposed and compared with Bayesian Linear Regression (BLR) and Decision Forest Regression (DFR). Experimental results show that the ensemble approach yields good results in seizing the multifaceted association among causal variables and also it extracted the most relevant hidden features of hydro meteorological rainfall system. [ABSTRACT FROM AUTHOR]

Of late, synthesis and application of microwave-absorbing materials have become absolutely necessary to minimize the looming threat of electromagnetic (EM) pollution. The present study discusses the fabrication of multifunctional polymer nanocomposite films, presents the analysis of the resulting films using a polyvinylidene fluoride (PVDF) matrix with M-type barium hexaferrite (BaFe 12 O 19) and graphitic carbon nitride (g-C 3 N 4) fillers, and reports on their application in EM interference (EMI) shielding in the X-band (8–12 GHz) frequency range. Crystalline BaFe 12 O 19 nanoparticles and g-C 3 N 4 were prepared and used to fabricate PVDF/BaFe 12 O 19 /g-C 3 N 4 composite films. The structural and compositional details of BaFe 12 O 19 nanoparticles and the films were analyzed, along with the fraction of β-phase PVDF. The morphological, magnetic, ferroelectric, and dielectric properties of the films were studied using field emission scanning electron microscopy (FESEM), vibrating sample magnetometry, ferroelectric hysteresis, and dielectric response, respectively. In addition, the microwave absorption efficiency of the films was analyzed in the X-band frequency range with a vector network analyzer (VNA) using the waveguide technique. Magnetic loss observed in the films was due to domain wall resonance, whereas polarization, conduction, and eddy current losses were attributable to the interaction of PVDF, magnetic BaFe 12 O 19 , and semiconducting g-C 3 N 4 fillers with the EM wave in the GHz frequency range. The VNA showed that the prepared PVDF/BaFe 12 O 19 /g-C 3 N 4 composite films show a shielding efficiency of 99.9 %. In particular, the total shielding effectiveness (SE T) of the film with 20 wt% of BaFe 12 O 19 loading was found to be 52 dB in the X-band frequency range. Furthermore, the prepared films were flexible and showed high β fraction, saturation magnetization, and dielectric loss, along with moderate magnetic loss and high shielding efficiency, making them potential microwave absorbers in the GHz frequency region. [Display omitted] • M-type BaFe 12 O 19 nanofiller & g-C 3 N 4 were prepared by autocombustion and solid state reaction methods. • Polymer nanocomposite films were fabricated by incorporating BaFe 12 O 19 and g-C 3 N 4 with PVDF using solution casting. • Structural and compositional of the prepared materials and composite films were confirmed by XRD, FTIR analysis and morphological analysis with FESEM. • The composite films show complex dielectric loss and magnetic loss, confirmed by dielectric measurement and VSM respectively. • The films are suitable for EMI shielding, confirmed by Vector Network analyzer in X-band frequency range. [ABSTRACT FROM AUTHOR]

• NiFe 2 O 4 , Fe 3 O 4 mono and hybrid magnetic nanofluids are synthesized through a two-step method. • NiFe 2 O 4 and Fe 3 O 4 nanoparticles are characterized through structural, magnetic, topographical, morphological, and surface charge analyses; and their electrical conductivity contributions are also studied. • The electrical conductivity analyses are performed for both the mono and hybrid magnetic nanofluids. • Maxwell, Bruggeman, Cruz, and Shen models are extended and applied to explain the conductivity of hybrid magnetic nanofluids. • Electrical conduction mechanism in hybrid magnetic nanofluids is described in terms of particle conductivity, electrophoretic conductivity and the conductivity due to Brownian motion. Highly stable aqueous magnetic mono nanofluids of nickel ferrite (NiFe 2 O 4), magnetite (Fe 3 O 4), and hybrid magnetic nanofluids of NiFe 2 O 4 -Fe 3 O 4 are synthesized through a two-step method. The structural analysis of the NiFe 2 O 4 and Fe 3 O 4 nanoparticles made through X-ray diffraction identifies their spinel cubic structure. The magnetic studies indicate their superparamagnetic nature, which is further confirmed through the Langevin fitting of the experimental data. The monodomain nature of nanoparticles is verified using the coupling constant, and a spherical morphology is observed using a transmission electron microscope. The surface charge of the nanoparticles is studied through zeta potential analysis. The electrical conductivity of the aqueous mono and hybrid magnetic nanofluids is measured for various concentrations and temperatures. The hybrid magnetic nanofluids show higher electrical conductivity values than those of both the mono nanofluids. For instance, NiFe 2 O 4 -Fe 3 O 4 (1.2 vol%) hybrid nanofluid is found to have a conductivity value of 18.91 μS/cm that is 1.5 times enhanced than that of Fe 3 O 4 mono nanofluid (12.87 μS/cm) and three times enhanced than that of NiFe 2 O 4 (6.43 μS/cm) mono nanofluid of same volume percentage at 303 K. A Maximum enhancement of 136 % is obtained for 1.2 vol% hybrid nanofluid with respect to water at 303 K and this enhancement further increases to 196 % with the rise in temperature to 323 K. There is no theoretical model found in literature to explain the electrical conductivity of hybrid nanofluids. Maxwell, Bruggeman, Cruz, and Shen models are applied to explain the conductivity of hybrid magnetic nanofluids. Through a comparison of experimental values with theoretical values, it is found that the Shen model, if modified suitably, can explain the electrical conduction of hybrid magnetic nanofluids. Also, the electrical conduction mechanism in hybrid magnetic nanofluids is described in terms of electrophoretic charge transportation and the Brownian motion. In addition, the magneto-electrical conductivity study is performed by measuring the electrical conductivity by applying a magnetic field of various strengths. The electrical conductivity, magneto-electrical conductivity studies and an understanding of electrical conduction mechanism are highly significant for magnetically transportable electronic cooling and conducting applications of hybrid magnetic nanofluids. [ABSTRACT FROM AUTHOR]

Researchers are focussing on creating sustainable environment by reducing the production and consumption of materials. The catalysis is not an exception, so there is always need for a catalyst that can perform multiple applications. Here, (Carica Papaya) and urea mediated CuCo2O4 nanocomposite was synthesized using simple co-precipitation method to perform drug loading, reduction of nitrocompounds and adsorption of pesticides. The prepared plant mediated CuCo2O4 (CCP) and urea mediated CuCo2O4 (CCU) was characterized using analytical techniques like XRD, UV-Vis, FT-IR, SEM-EDAX, TEM and DLS studies etc. The XRD patterns of CCP and CCU were indexed to the cubic spinal structure with the crystallite size of 11.9 and 27.6 nm by calculated using Scherrer’s equation. The typical FT-IR spectra of CCP and CCU composites exhibited two extremely strong vibration peaks at the range of 658 − 657 and 540–545 cm− 1 due to the presence of the Co-O and Cu-O bond vibrations respectively. The band gap values (Eg) were found to be 1.3 and 1.5 eV and thermal stability of the prepared CuCo2O4 was analyzed using thermogravimetric studies. The SEM images confirmed the spherical morphology with the particle size of 89.9 and 107 nm respectively. The catalytic efficiency was analyzed by using acetaminophen as a sample drug for finding the loading efficiency of CCP and CCU found to be linear with time of loading had good R2 values of 0.93 and 0.91 respectively. The drug loading efficiency or entrapment efficiency of the CCP and CCU was found to be 72.8 and 85.2% after 48 h of drug loading respectively. The catalyst weight dependant activity of CCP and CCU in the reduction of 2-nitrophenol and 2-nitroaniline effectively witnessed the ability of CCP and CCU over other catalysts. Furthermore, CCP and CCU were used as the adsorbents and made to adsorb the real time agricultural pesticide like pendimethalin for a period of 130 min and the obtained cumulative data suggested the superiority of CCP over CCU in the above catalytic applications. [ABSTRACT FROM AUTHOR]

A core–shell nanofiber with a neodymium orthoferrite (NdFeO 3) core and lead zirconium titanate (PbZr 0.52 Ti 0.48 O 3) shell was prepared in this study using the sol-gel electrospinning method. Structural properties of the nanofiber were analysed using the X-ray diffraction (XRD) method, which revealed that a perovskite structure was formed. The strain was calculated using Williamson-Hall (W–H) plot. Functional groups of the nanofiber were studied using Fourier transform infrared (FTIR) spectroscopy. Morphological studies revealed the core diameter of the nanofiber to be 65 nm and its shell diameter to be 128 nm. The elemental analysis of core-shell nanofiber was made using Energy Dispersive X-ray Spectroscopy (EDS) which proved the formation of NdFeO 3 and PbZr 0.52 Ti 0.48 O 3 composite in the stoichiometric ratio. Topography analysis using atomic force microscopy found the average fibre diameter to be 135 nm. The nanofiber exhibited antiferromagnetic behaviour, with a saturation magnetization of 0.48 emu/g. Dynamic contact electrostatic force microscopy (DC-EFM) studies revealed that the nanofiber showed domain-switching behaviour. The ferroelectric hysteresis plots showed that the nanofiber exhibited a maximum polarization of 5.45 μC/cm2 at 20 kV/cm. Also, its dielectric constant was 268 at 100 Hz. The leakage current study revealed a butterfly-shaped J-E loop, which further proved the ferroelectric behaviour of the nanofiber. The mechanism behind the leakage current was identified to be the Schottky emission. The P-E loops recorded under external magnetic fields of different strengths exhibited variations in the polarization, indicating the presence of cross-coupling between electric and magnetic order parameters. Because of the high dielectric constant displayed by the magnetoelectrically active NdFeO 3 –PbZr 0.52 Ti 0.48 O 3 core–shell nanofiber, it can be a promising candidate for a number of applications, such as data storage devices, multimedia devices, spintronics and magnetic field sensors. [ABSTRACT FROM AUTHOR]

The title compound, C19H18O5, has been synthesized using the Claisen-Schmidt condensation reaction from the mixture of 2,3 dihydro-4H-1-benzopyran-4-one and 2,4,5 trimethoxy benzaldehyde using ethanol as solvent. The crystal has been characterized for its 3 D structure and structural parameters were elucidated via the X-ray diffraction (XRD) method. The crystallographic parameters such as bond lengths, bond angles, and torsion angles were estimated and are comparable with the literature values. Hirshfeld surfaces namely dnorm, electrostatic potential, shape index, and curvedness were analyzed to visualize and to evaluate the weak intermolecular interactions, positive and negative potential regions, C-H...π, and π...π stacking interactions, respectively. The 2 D fingerprint plots for the whole and delineated interactions were also generated to estimate their contributions to the total Hirshfeld surface. The pairwise intermolecular interactions were calculated as the sum of four scaled energy components namely electrostatic (Eele), polarization (Epol), dispersion (Edis), and exchange-repulsion (Erep), and graphically represented as energy frameworks. The energy frameworks analysis reveals that the total stabilizing energy is highly influenced by dispersion (Edis) energy than the other components. The material has been screened for its cytotoxic effect on normal cell lines (VERO) and anticancer activity on breast cancer cell lines (MCF-7) and the material is found to be a potential candidate against cancer proliferation. [ABSTRACT FROM AUTHOR]

Zn-doped nickel ferrite nanoparticles (Zn x Ni (1- x) Fe 2 O 4) were synthesized using the co-precipitation technique. The structural and compositional studies of the Zn x Ni (1- x) Fe 2 O 4 nanoparticles revealed their face-centred cubic spinel structure and an appropriate amount of Zn doping in nickel ferrite nanoparticles, respectively. The morphological analysis had been carried out to obtain the particle size of the synthesized nanoparticles. The magnetic studies revealed the superparamagnetic nature of the Zn x Ni (1- x) Fe 2 O 4 nanoparticles, and the maximum magnetization of 30 emu/g for the Zn 0.2 N 0.8 Fe 2 O 4 sample. The M − H curves were fitted with the Langevin function to obtain the magnetic particle diameter of Zn x Ni (1- x) Fe 2 O 4 nanoparticles. The electrical conduction in Zn x Ni (1- x) Fe 2 O 4 nanoparticles was explained through the Verway hopping mechanism. The Zn 0.2 N 0.8 Fe 2 O 4 nanoparticle exhibited a higher electrical conductivity of 42 μS/cm and surface charge of −29/7 mV due to the enhanced hopping of Fe3+ ions in the octahedral sites. Owing to this nature, they were identified as the suitable candidates in the applications such as thermoelectrics, hyperthermia, magnetic coating and for the preparation of conducting ferrofluids. [ABSTRACT FROM AUTHOR]

This research focuses on crafting highly flexible and efficient mechanical and magneto-mechano-electrical (MME) nanogenerators using electrospun poly (vinylidene fluoride)-nickel ferrite (PVDF-NiFe 2 O 4) composite fibers, tailored for self-powered and wireless sensor networks. Nickel ferrite nanoparticles, averaging 40 nm in crystallite size, were synthesized through the autocombustion method and integrated as fillers within the PVDF matrix. Analysis via XRD and FTIR confirmed a greater presence of the ferroelectric β-phase in the PVDF electrospun fibers, accentuated by the incorporation of NiFe 2 O 4. Notably, the mat containing 5 wt% of NiFe 2 O 4 boasted an estimated 86 % β-phase. SEM micrographs depicted the formation of uniform bead-free fiber with a diameter of 900 nm. VSM analysis verified the ferrimagnetic properties of the composite fiber mats, registering a maximum saturation magnetization of 4.6 emu/cm3. Under mechanical tapping, the nanogenerator yielded an output voltage of 16.5 V and a power of 0.8 μW. The study also compared the performance of two MME nanogenerator geometries (rectangular and truncated) under an AC magnetic field of 10 Oe. Remarkably, the MME nanogenerator with a truncated geometry exhibited superior performance, generating 6.2 V, a 50 % increase over the rectangular counterpart. [Display omitted] • Fabrication of flexible multifunctional electrospun PVDF/NiFe 2 O 4 fiber mats. • Incorporation of NiFe 2 O 4 in PVDF plays an important role in enhancing β phase. • Nanogenrators and magneto-mechano-electric (MME) nanogenerators were developed. • The study of geometry effect on MME nanogenerator energy harvesting performance. • The nanogenerator exhibited Vpp of 16.5V and 50 % enhancement in truncated geometry. [ABSTRACT FROM AUTHOR]

In the present work, magneto thermoelectric behavior of the Zn-doped magnetite nanofluids is reported. Thermal and electrical conductivity studies have been done, compared and determined to be in line with the theoretical models. Thermoelectric voltage measurements have been carried out in the fluid samples for quite a number of temperature differences at various magnetic fields, and the Seebeck coefficient is calculated from the obtained measurements. It is observed that the fluid samples, which includes magnetite nanoparticle with zinc dopant concentration x = 0.2 shows better enhancement in electrical conductivity, mild enhancement in thermal conductivity and higher Seebeck coefficient value among all the samples. Also, a higher enhancement of 26% is observed in the Seebeck coefficient value of the same sample with an application of 770 G magnetic field. Hence, this is identified as a potential candidate for energy harvesting purposes such as thermoelectric generators in automobile systems, industries and etc. [ABSTRACT FROM AUTHOR]

The study used nickel ferrite NiFe 2 O 4 /activated carbon (NiFe 2 O 4 /AC) as a means to remove organic dyes (methylene blue and Reactive red 120) from water-based solutions. The produced photocatalysts were characterized based on their morphological, structural, particle size, and surface charge characteristics. The transmission electron microscopy (TEM) pictures indicated that the NiFe 2 O 4 particles, with an average diameter of around 2–2.5 μm, were evenly distributed and adhered to the outermost layer of the AC nanosheets. The BET analysis revealed that the 10-NiFe 2 O 4 /AC material had a surface area of 176 m2/g, a pore volume of 0.354 cm3/g, and an average pore diameter of 0.805 nm. The nanocomposite, as opposed to pure NiFe 2 O 4 and clean AC, demonstrates a notably enhanced photocatalytic degradation efficiency for methylene blue (MB) and Reactive red 120 dye under visible light conditions. The findings indicate that the AC loaded with 10 % NiFe 2 O 4 is the most effective photocatalyst, exhibiting a maximum degradation efficiency of 100 % towards MB dye. Additionally, it displays a high mechanical constant, excellent stability, and ease of recycling. The nanocomposite exhibits increased photocatalytic activity owing to the significant reduction in charge carriers recombination, improved capacity to absorb visible light, and the synergistic impact resulting from the heterojunction with NiFe 2 O 4 and AC. The radical entrapment research revealed that the primary active compounds responsible for the photocatalytic degradation process are superoxide (O 2 −) and hydroxyl (OH*). [Display omitted] • A facile, controllable and low cost hydrothermal synthesis method has been used to fabricate NiFe 2 O 4 /AC nanocomposite photocatalyst. • Maximum photodegrdation efficiency towards MB (100%), high apparent constant (0.0012 min-1), and long-term stability under UV light • This could be due to high conductivity of AC and suppress the recombination of electron-hole pair. [ABSTRACT FROM AUTHOR]

Fabrication of magnetoelectric (ME) polymer composite films by embedding ferromagnetic cobalt ferrite (CoFe 2 O 4) nanofibers into electroactive poly(vinylidene fluoride–hexafluoropropylene) (P(VDF-HFP)) matrix is reported. Single-phase CoFe 2 O 4 nanofibers made of cubic spinel nano crystallites are synthesized by using electro-spinning method, whereas the solution-casting technique is adapted to prepare flexible polymer composite films. The influence of CoFe 2 O 4 nanofiber on structural, functional, magnetic, ferroelectric, and magnetoresistance properties of the composite films is investigated. The cross-coupling between ferroelectric and ferromagnetic orderings is ensured, by the variations of ferroelectric response at different magnetic fields. These magnetoelectric films are found to exhibit a negative tunneling magnetoresistance (TMR) effect with maximum TMR% of 28 for the film with 20 wt% of CoFe 2 O 4 loading. The dielectric constant and electrical energy storage density of the films are increased with the addition of CoFe 2 O 4 nanofiber. The ME films exhibiting TMR and high energy density can be the potential candidates for multifunctional device applications such as memory and spintronics devices, magnetic sensor, and bio-sensor. [ABSTRACT FROM AUTHOR]

Flexible free standing electrospun poly (vinylidene fluoride)/ZnFe 2 O 4 composite fiber mats were synthesized through electrospinning technique. Structural and morphological studies of PVDF/ZnFe 2 O 4 composite fibers were examined by X-ray diffraction and scanning electron microscopy. The functional groups and the percentage of β phase were analysed using FTIR studies. 92% beta phase was achieved with the incorporation of ZnFe 2 O 4 filler. The enhancement in dielectric and ferroelectric properties of the composite fiber mats were observed with a maximum dielectric constant and polarization values of 15 and 0.72 μC/cm2 respectively for 20 wt% filler loading. The domain switching behaviour of the mats were analysed using DC-EFM. Vibration sample magnetometry results revealed the antiferromagnetic nature of the composite fiber mats with a maximum magnetization of 0.18 emu/cm3. Further, the energy storage density of the mats was studied and a maximum energy storage density of 239 mJ/cm3 was obtained which was 1.4 times than that of pure PVDF mat. [ABSTRACT FROM AUTHOR]

The major challenge of feature based blind steganalysers lies in designing effective image features which give true evidence of the stego noise rather than the natural noise present in the images. Hence they report low detection accuracy in real time implementation in spite of employing 100s of features in the process. In this paper, we coin a new paradigm for detecting steganography by examining the task as a three-steps process with the following repercussions: (a) employing curvelet transform denoising as a pre-processing step that produces better stego noise residuals suppressing the natural noise residual rather than a general denoising step before feature extraction, (b) extracting various steganalytic features, both in spatial domain as well transform domain and (c) implementing the system based on an efficient classifier, multi-surface proximal support vector machine ensemble oblique random rotation forest, that provides detection rate superior to other existing classifiers. Extensive experimentation with huge database of clean and steganogram images produced from seven steganographic schemes with varying embedding rates, and using five steganalysers, shows that the proposed paradigm improves the detection accuracy substantially and proves to be a high performance strategy even at low embedding rates. This model can be employed as a preprocessing component for any image steganalyser and high performance accuracy can be obtained. [ABSTRACT FROM AUTHOR]

• CoFe 2 O 4 fibers were synthesised by using electrospinning technique. • Continuous fiber nature of CoFe 2 O 4 proved by SEM, TEM and AFM characterization. • Improved magnetic properties of CoFe 2 O 4 confirmed by VSM studies. • Room temperature gas sensor performances of CoFe 2 O 4 under different test gases were tested. In this study, ferromagnetic cobalt ferrite (CoFe 2 O 4) fibers were synthesized by electrospinning technique using a DMF/ethanol mixed precursor solution of poly (vinyl pyrrolidone) (PVP) and cobalt and iron (III) nitrates. The as-spun precursor fibers were characterized using thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) analyses and calcined at 500, 600 and 800 °C with a heating rate of 2 °C/min to obtain CoFe 2 O 4 fibers. Morphological studies confirmed the formation of a continuous bead-free fiber structure in the calcined samples with an average fiber diameter and particle size of 208 nm and 48 nm respectively. Magnetic hysteresis loops of CoFe 2 O 4 fibers revealed their ferromagnetic nature, with a maximum saturation magnetization of 76.5 emu/g and a coercivity of 948 Oe. At room temperature, the variation of resistance and the corresponding response toward various test gases of different concentrations were systematically investigated. The sensing response of CoFe 2 O 4 fibers toward ammonia was found to be better than toward other test gases such as ethanol, methanol, acetone, and 2-propanol. CoFe 2 O 4 fibers showed good reproducibility and a maximum response of 0.42 at 900 ppm concentration of ammonia. They also exhibited the ability to sense a very low concentration of ammonia (even at 25 ppm) at room temperature. [ABSTRACT FROM AUTHOR]

To synthesize stable nanofluids of zinc-doped cobalt ferrite (Zn x Co (1-x) Fe 2 O 4) with various dopant concentrations (x = 0, 0.1, 0.2, 0.3 and 0.4), a two-step method is adopted. X-ray diffraction pattern was used to confirm the phase purity of the ferrite whereas EDAX analysis was performed to determine the chemical composition. The magnetic studies performed on the samples reveal that they show monodomain structure and superparamagnetic nature. The electrical conductivity of the undoped and zinc doped cobalt ferrite nanoparticles is studied and is explained through hopping mechanism. The electrical conductivity of all the nanofluids is higher than that of water, the base fluid, due to the formation of electrical double layer (EDL) in the dispersion. An increase of 90% in electrical conductivity is reported in the Zn 0.2 Co 0.8 Fe 2 O 4 sample at room temperature compared to base fluid, which is due to higher surface charge and zeta potential. The effect of temperature on electrical conductivity of nanofluids is elucidated using percolation effect of ferrite nanoparticles in the base fluid. Also, it is noted that magnetic field has no effect over the formation of EDL, and hence, there is no change in electrical conductivity with respect to applied field. The experimental values are compared with Maxwell and Shen's models, which are found compactible with the framework of Shen's model. • Water based Zn x Co 1-x Fe 2 O 4 nanofluids have been synthesized. • Magnetic studies reveal that, all the samples show superparamagnetic nature. • Electrical studies are made at various temperatures and magnetic fields. • The maximum enhancement is shown by Z2 sample due to their higher surface charge. • The experimental values are found compatible with the framework of Shen's model. [ABSTRACT FROM AUTHOR]

Flexible and free standing magnetoelectric polymer nanocomposite electrospun membranes, which exhibit both ferroelectric and magnetic orderings simultaneously, are fabricated. CoFe 2 O 4 nanoparticles of different weight percentages are embedded as fillers in poly (vinylidene fluoride) (PVDF) matrix. The percentage of electroactive β phase is analysed using XRD and FTIR studies. Investigations on the effect of filler on the structural, functional, morphological properties are discussed. CoFe 2 O 4 content in PVDF plays a main role in controlling the α and β phase conformations and makes significant effect on the ferroelectric and ferromagnetic properties of PVDF/CoFe 2 O 4 membranes. The domain switching behaviour of these ferroelectric membranes is confirmed through DC-EFM studies. In addition to the coexistence of ferroelectric and ferromagnetic orderings, the cross coupling between them have been proved. [ABSTRACT FROM AUTHOR]

Nanocomposite films of poly(vinylidenefluoride-hexafluoropropylene) P(VDF-HFP) matrix and ZnFe2O4nanoparticle filler were prepared by spin coating technique. The presence of ZnFe2O4in the polymer matrix was confirmed by X-Ray diffraction technique (XRD). The morphological analysis was carried out using field emission scanning electron microscope (FE-SEM) which revealed the uniform distribution of ZnFe2O4nanoparticles with the polymer matrix. An AC conductivity of about 10−4S/cm was observed for all the films at 1 MHz. The dielectric constant of 20 wt% of P(VDF-HFP)/ZnFe2O4was observed to be 34 at 200 Hz which is three times higher than that of plain P(VDF-HFP). [ABSTRACT FROM PUBLISHER]

Free-standing, flexible films of poly(vinylidene fluoride–hexafluoropropylene) (P(VDF-HFP)) were prepared by spin coating technique, and the effects of heat treatment and poling on the formation of electroactive β phase were studied. The X-ray diffraction, Fourier-transform infrared spectroscopy, Field emission scanning electron microscopy and Atomic force microscopy studies proved that the melt-quenching process influences the transformation of non-ferroelectric α phase to ferroelectric β-phase, when compared to heat-drying process. The variation in the β-phase content resulted in the enhanced ferroelectric response in the melt-quenched samples, which was proved by the dynamic contact electrostatic force microscopy (DC-EFM) studies and also by the ferroelectric hysteresis. The polarization switching behavior of the films was also investigated with DC-EFM. The electrical poling at 30 MV/m further enhanced the ferroelectric nature of the films by 29–30%. The films exhibited high dielectric constant, low dielectric loss, and low-leakage current, and it was identified that the leakage current in the films was originated due to the Schottky emission. [ABSTRACT FROM AUTHOR]

The success rate for blind or universal steganalysis lies in the ability to extract the statistical footprints of image features. Further, the choice of machine learning (ML) algorithm is crucial to distinguish the stego image more precisely from the untouched clean images. Literature suggests that most steganalysis approaches report less favorable detection accuracy despite considering many features. This study presents a three-step process to accurately identify the clean and stego images to solve this issue. We used the curvelet denoising as an initial phase during the first step to suppress the natural noise residuals (NRs) by producing the stego NRs. Secondly, it extracts the Third-order Markov-chain sample transition probability matrices as features. Finally, the oblique decision tree ensemble using a multisurface proximal support vector machine (SVM) classifier has been utilized to achieve greater detection accuracy than the state-of-the-art classifiers. The experiments are performed on an extensive database comprising clean and stego images generated from nine embedding schemes with varying payloads. The experimental results suggest that an accuracy of 93.12 has been achieved using the proposed Third order subtractive pixel adjacency matrix (SPAM) features with an ensemble classifier. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) multiferroic materials possess extensive research interest as a result of their use in a variety of sectors. In this work, the optical properties of plain P(VDF-HFP) film and P(VDF-HFP)/SrFe 12 O 19 composite films are investigated through UV-Vis absorption spectroscopy. In addition, the ME coupling of SrFe 12 O 19 nanofibers reinforced P(VDF-HFP) composite films is investigated though magnetodielectric (MD) measurements. The parameters such as dielectric constant, capacitance, dielectric loss and impedance of the composite films are found to change with the applied magnetic field which is attributed to the direct ME coupling of the composite films. The prepared ME films show a negative tunneling magnetoresistance (TMR) effect with maximum TMR% of 14 % for the film (PSNF20) with 20 wt% of SrFe 12 O 19 nanofiber loading. Photodetectors are fabricated using the films as active elements and the performance of the photodetectors is studied under various intensities of visible light radiation. All the devices exhibit good photosensitivity, responsivity and specific detectivity at an illumination intensity of 20 mW/cm2. The photodetector (PD20) fabricated using PSNF20 as an active element has the maximum rise/decay time, photosensitivity, responsivity and specific detectivity values as 468 /553 ms, 2.7 × 103, 22 mA/W and 6.77 × 1013 Jones, respectively at 20 mW/cm2. In addition, the performance of the devices is analyzed by subjecting the active element to external magnetic field. The photosensitivity, responsivity and specific detectivity all improve, showing that the magnetic field has an effect on the photodetector. The above parameters are maximum for PD20 device and the values are 4.3 × 103, 26 mA/W and, 8.01 × 1013 Jones, respectively at 4000 Oe and 20 mW/cm2. Thus, the prepared flexible magnetoelectric films of P(VDF-HFP)/SrFe 12 O 19 nanofiber composites have been shown to be good options for the magnetic field tuned photodetector applications such as environmental sensing monitor, safety and security, optical communication systems, magnetic sensors, piezoelectric sensors and spintronics devices. • Flexible PVDF-HFP/SrFe 12 O 19 composite films are prepared by solution casting method. • The ME coupling of PVDF-HFP/SrFe 12 O 19 films is studied through MD measurement. • PVDF-HFP/ SrFe 12 O 19 films show negative tunneling magnetoresistance behavior. • Photodetectors (PDs) are fabricated by using ME PVDF-HFP/SrFe 12 O 19 composite films. • The performance of the PDs are studied in the presence of external magnetic fields. [ABSTRACT FROM AUTHOR]

Highly crystalline cobalt nano ferrites have been synthesized by the combustion route using d l -alanine, a racemic mixture of right handed ( d ) and left handed ( l ) chemical forms of alpha-alanine, as fuel. The synthesized samples were annealed at two different temperatures, viz. 500 °C and 800 °C, for 2 h to investigate the temperature effect on crystallite size, phase purity, thermal stability, Curie temperature, and magnetic properties. Formation of single-phase spinel nanoparticles in both the as-prepared and annealed conditions has been observed. High saturation magnetization (71.1 emu/g) for as-prepared sample and a high coercive field (1400 Oe) for the sample annealed at 500 °C/2 h were obtained. [ABSTRACT FROM AUTHOR]

This article reports the synthesis of barium nickel hexaferrite-lead zirconium titanate (Ba 2 Ni 2 Fe 12 O 22 -Pb(Zr 0.52 Ti 0.48)O 3) core-shell nanofibers through sol-gel electrospinning method. Direct magnetoelectric and magnetodielectric coupling studies were performed on the synthesized electrospun core-shell nanofibers. The structure, functional, morphological, magnetic, dielectric, leakage current, and ferroelectric properties were also analyzed. X-ray diffraction studies revealed the hexagonal crystal structure of the core and the tetragonal structure of the shell. The Fourier transform infrared spectroscopy analysis showed the fundamental functional groups present in the nanofibers. Scanning electron microscopy studies showed that the diameter of the nanofibers was 404 nm, and elemental analysis by energy-dispersive X-ray spectroscopy showed the stoichiometric formation of Ba 2 Ni 2 Fe 12 O 22 and Pb(Zr 0.52 Ti 0.48)O 3 in the composite. Microstructure studies using a transmission electron microscope revealed the formation of core-shell nanofibers with a clear interface between the magnetic Ba 2 Ni 2 Fe 12 O 22 (BNFO) core and the ferroelectric Pb(Zr 0.52 Ti 0.48)O 3 (PZT) shell. Selected-area electron diffraction analysis showed the Ba 2 Ni 2 Fe 12 O 22 and Pb(Zr 0.52 Ti 0.48)O 3 phases to be highly crystalline. At room temperature, the synthesized nanofibers exhibited well-defined ferroelectric and magnetic hysteresis loops. Dielectric and leakage current studies were performed. Direct magnetoelectric and magnetodielectric studies were also performed to study the cross-coupling between the ferroic orders of the nanofiber. Moreover, using Landau's energy expression, the type of magnetoelectric coupling was proved to be biquadratic. The enhanced magnetoelectric behavior of the Ba 2 Ni 2 Fe 12 O 22 –Pb(Zr 0.52 Ti 0.48)O 3 core–shell nanofiber confirms that the nanofiber is a potential candidate for high-performing magnetic field sensors, magnetically tuned capacitors, multimedia transducers, and spintronic devices. [ABSTRACT FROM AUTHOR]

CuO-ethylene glycol nanofluids of various concentrations have been synthesized using ultrasonically assisted two step method. Ultrasonic and thermal investigations are made on the nanofluids at different temperatures ranging from 308 K to 328 K. The intermolecular interactions in CuO-ethylene glycol nanofluids are realized through the ultrasonic velocity and it is found that the CuO-ethylene glycol interactions surpass the CuO-CuO interactions. The variations of ultrasonic velocity with respect to temperature confirm the weakening of the intermolecular adhesive forces at elevated temperatures. In addition to the interaction studies, a new methodology is proposed to find thermal conductivity of nanofluids using ultrasonic velocity. The results, thus obtained through ultrasonic method, are found to agree well with those obtained through the transient line heat source technique, which confirms the aptness of the proposed method. [ABSTRACT FROM AUTHOR]

Highlights: [•] Stable cobalt ferrite magnetic nanofluids are prepared. [•] Structural, Magnetic and ultrasonic parameters are estimated. [•] Temperature and magnetic field dependent acoustic response have been investigated. [•] Open and close packed structures of water have been used to explain temperature effect. [•] Ultrasonics is used as an effective tool to elucidate the cluster formation. [ABSTRACT FROM AUTHOR]

Abstract: Nickel ferrite nanoparticles have been synthesized by sol–gel auto combustion route. The significant role played by nitric acid added to the precursor solution in controlling the reaction rate phase purity, crystallinity, crystallite size, thermal and magnetic properties of nanoparticles was explored and reported. Also, the influence of annealing on the properties were studied. Samples of average crystallite size ranging from 10nm to 40nm have been obtained by controlling the HNO3 concentration and by increasing the annealing temperature. The size-dependent structural, thermal and magnetic properties were investigated and reported. The Hopkinson peak was observed for all the crystalline samples near the Curie temperature. The highest value 47.3emu/g of saturation magnetization was obtained for the sample prepared with higher concentration (6mol/L) of HNO3. [Copyright &y& Elsevier]

• Fabrication of flexible magnetoelectric (ME) P(VDF-HFP)/SrFe 12 O 19 composite films. • Inclusion of SrFe 12 O 19 nanofiber enhances the polar β-phase in P(VDF-HFP) matrix. • P(VDF-HFP)/SrFe 12 O 19 films exhibit enhanced dielectric and ferroelectric properties. • A strong strain mediated ME coupling exists in the P(VDF-HFP)/SrFe 12 O 19 films. • P(VDF-HFP)/SrFe 12 O 19 films' energy storage capacity is tuned by magnetic fields. Flexible, self-standing magnetoelectric (ME) polymer composite films were prepared using the solution casting method by reinforcing one-dimensional ferromagnetic strontium ferrite (SrFe 12 O 19) nanofibers, synthesized using the electrospinning method, into poly(vinylidene fluoride–hexafluoropropylene) (P(VDF-HFP)) matrix. The effects of loading of SrFe 12 O 19 nanofibers on the functional, structural, magnetic, dielectric, and ferroelectric properties of P(VDF-HFP) were investigated. The loading enhanced the electroactive β-phase of the films, as confirmed by XRD and FTIR analyses. The ME coupling that existed in the composite films was confirmed by the changes in ferroelectric parameters under various magnetic fields. The energy storage capacity and dielectric constant of the composite films were enhanced with the addition of SrFe 12 O 19 nanofibers, with the maximum values of 56 at 100 Hz and 1678 mJ/cm3 at 444 kV/cm, respectively, in the composite film with 20 wt% SrFe 12 O 19 nanofibers. The energy storage capacity was further enhanced and tuned by applying an external magnetic field. Thus, this work reports an innovative approach to tuning the energy storage capacity of ME polymer composite films through a magnetic field and also describes use of these films for a wide range of applications, such as energy storage and memory devices and magnetic sensors. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ecofriendly ZnO–coconut oil nanofluids of various concentrations are synthesized. [•] Rheological studies have been made at various temperatures and shear rates. [•] Causes for non Newtonian behavior are discussed. [•] Measured viscosity is found to agree with existing theoretical models. [•] New correlations of viscosity with concentration and temperature are proposed. [Copyright &y& Elsevier]

Abstract: Novel coconut oil based copper oxide nanofluids of various concentrations have been prepared by ultrasonically assisted two step method. Viscosity studies have been made experimentally and theoretically at various temperatures and shear rates for different concentrations of nanofluid ranging from 0% to 2.5%. Shear thinning, a non-Newtonian behavior is observed in all the samples. The shear thinning is higher at lower shear rates and higher concentrations. The shear thinning at low concentration is attributed to the non-Newtonian behavior of carrier liquid, but at higher concentration there is a considerable contribution from particle too. The measured viscosities of nanofluids are compared with existing theoretical models and found to have very slight deviation due to size, morphology and interactions. New empirical correlations are proposed for predicting viscosity of CuO–coconut oil nanofluid at various temperatures and concentrations. [Copyright &y& Elsevier]

A Calotropis gigantea supported Ag–Cu–Co trimetal oxide was synthesized for larvicidal, antioxidant, antibacterial and photocatalytic degradation studies. The optical and structural properties of the Ag–Cu–Co oxide were analyzed using UV-vis spectroscopy, FT-IR spectroscopy, XRD, FESEM-EDAX, and DLS studies, etc. The UV-vis spectra showed a maximum absorbance (λmax) in the ranges of 225–273 and 303–380 nm. The XRD study revealed that the C. gigantea supported Ag–Cu–Co oxide has an average crystallite size in the range of 18–20 nm. The spherical morphology of the Ag–Cu–Co oxide with an average grain size in the range of 80–110 nm was observed from FESEM analysis. The hydrodynamic diameter was found to be in the range of 150–230 nm using DLS analysis. The stability of the nanocomposite was confirmed by its negative zeta potential value. The high % inhibition against DPPH was found to be 72.15% at 500 μg mL−1 and the maximum zone of inhibition was found to be 25 mm against 240 μg mL−1 of E. coli. The % mortality was observed to be approximately 98% against A. aegypti at 25 μg mL−1. The catalyst was used to degrade methylene blue dye, with a degradation efficiency of 87.9%. Therefore, the current study proposes that the C. gigantea supported Ag–Cu–Co oxide nanoparticles have good capability for use in photocatalysis and biological applications. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication of flexible Poly (vinylidine Fluoride)/Fe3O4 magnetoelectric nanocomposite films with different weight fractions of Fe3O4 nanoparticles is explained in this paper. The effects of nano Fe3O4 content on the structural, chemical, thermal, and magnetoelectric properties of PVDF matrix are discussed. XRD and FTIR results reveal the interaction between the filler and the matrix and also they suggest that the β phase contribution can be significantly controlled by the inclusion of nano Fe3O4. Thermal stability and melting point behavior of the composite films are investigated through TG/DTA. The existence of ferrimagnetism and ferroelectric properties in the films are proved through the magnetization and polarization studies. The hysteresis loops show the largest polarization and magnetization values at 0.14 wt% of Fe3O4. Also, the dependence of ferroelectric polarization on temperature is investigated and reported. [Copyright &y& Elsevier]

Abstract: Magnetite nanofluids of various concentrations have been prepared through co-precipitation method. The structural and magnetic properties of the magnetic nanofluids have been analyzed which respectively revealed their face centered cubic crystal structure and super paramagnetic behavior. Ultrasonic investigations have been made for the nanofluids at different temperatures and magnetic fields. Open- and close-packed water structure is considered to explain the temperature effects. The inter particle interactions of surface modified nanomagnetite particle and the cluster formation are realized through the variations in ultrasonic parameters. [Copyright &y& Elsevier]

Abstract: A combustion route of synthesizing highly crystalline single phase nickel ferrite (NiFe2O4) spinel nanoparticles using various amounts of dl-alanine as fuel has been reported in this paper. The role of the amount of fuel is found to be significant in the size control and phase purity of nano crystalline samples. The structural, thermal, morphological and magnetic studies have been carried out. XRD patterns reveal the formation of highly crystalline nano NiFe2O4 with high degree of phase purity when fuel concentration is maintained at 1M and 2M. FTIR spectra also prove the formation of pure nano NiFe2O4. The temperature and fuel effects are found to have strong influence on size, structural, and magnetic properties of materials. The magnetic measurements show that the nano NiFe2O4 samples exhibit soft ferromagnetism with the highest saturation magnetization Ms at room temperature as 42.53emu/g. [Copyright &y& Elsevier]

• Fabrication of flexible magnetoelectric PVDF/NiFe 2 O 4 nanofiber composite films. • Addition of NiFe 2 O 4 in PVDF plays an important role in transforming α to β phase. • PVDF/NiFe 2 O 4 films exhibit enhanced ferroelectric and magnetic properties. • DC EFM and MFM studies prove the multiferroic nature of the composite films. • PVDF/NiFe 2 O 4 nanogenerator and MME generators, generate a voltage of 10 V and 4.8 V. Flexible nanocomposite films of poly(vinylidene fluoride)(PVDF)/nickel ferrite (NiFe 2 O 4) fiber were made using solvent casting method. The NiFe 2 O 4 fibers with a diameter of 400 nm were synthesized initially by means of electrospinnig technique. Studies of XRD and FTIR confirmed the formation of both α and β phases in the composite films. The presence of α-phase was diminished with the incorporation of NiFe 2 O 4 and a maximum β-phase percentage (68%) was obtained. SEM and AFM analyses also demonstrated the transformation of the microstructures from α to β phase. The ferroelectric properties were tested with respect to NiFe 2 O 4 loading and the composite film with 10 wt% NiFe 2 O 4 exhibited a high P max value of 1.46 μC/cm2. VSM studies revealed the ferrimagnetic behaviour of the films and exhibited a maximum saturation magnetization value of 4.2 emu/cm3. Local ferroelectric properties were investigated through their domain switching behavior using dynamic contact electrostatic force microscopy (DC-EFM), and magnetic force microscopy (MFM) was used to analyze the magnetic properties. The magnetoelectric cross-coupling between ferroelectric and ferrimagnetic orderings is verified through the variations in ferroelectric parameters under different magnetic fields. Then a nanogenerator was fabricated using the composite films and generated an open circuit voltage of 10 V (peak-peak). Additionally, these films were made into magneto-mechano-electric (MME) generator, which could generate a 4.8 V (peak-peak) output voltage under a weak AC magnetic field of 10 Oe at 50 Hz. [ABSTRACT FROM AUTHOR]

A two-step synthesis method was used to prepare a flexible PVDF/ZnFe 2 O 4 multiferroic nanocomposite film. ZnFe 2 O 4 nanofibers synthesized using electrospinning technique were incorporated into a PVDF matrix to form PVDF/ZnFe 2 O 4 composite films through the solution-casting process. XRD patterns confirmed the formation of the polar β-phase in films, which is responsible for ferroelectricity. The percentage of the β-phase, calculated by FTIR analysis, reached 88% with the incorporation of ZnFe 2 O 4 in PVDF. The transformation of α to β-phase microstructure were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The dielectric constant and tangent loss of the composites with respect to ZnFe 2 O 4 loading were measured. The dielectric constant increase with the increasing concentration of ZnFe 2 O 4 , and a maximum value of 30 was obtained for a ZnFe 2 O 4 concentration of 15 wt%. Ferroelectric properties were analyzed by taking into consideration the domain switching behavior, which was investigated by dynamic contact electrostatic force microscopy (DC-EFM), whereas the magnetic properties were analyzed using magnetic force microscopy (MFM). The as-synthesized composite films were further used to fabricate a nanogenerator, which was capable of generating up to 7 V (peak–peak) as a maximum open circuit voltage for a 15 wt% ZnFe 2 O 4 -loaded film at 1.5 N of applied force. In addition, the nanogenerator delivered an output power of 4 μW at a load resistance of 500 kΩ, and the results were compared with previous results. • Fabrication of flexible multiferroic PVDF/ZnFe 2 O 4 nanofiber composite films. • Addition of ZnFe 2 O 4 in PVDF plays an important role in transforming α to β phase. • PVDF/ZnFe 2 O 4 films exhibit enhanced dielectric and ferroelectric properties. • DC EFM and MFM studies prove the multiferroic nature of the composite films. • PVDF/ZnFe 2 O 4 nanogenerator generates a voltage of 7 V and power of 4 μW. [ABSTRACT FROM AUTHOR]

Highly stable aqueous nanofluids of magnesium ferrite (MgFe 2 O 4) have been synthesized in various concentrations through a two-step method. Their thermophysical properties are analyzed by studying viscosity and thermal conductivity with respect to the concentration and temperature. The structural analysis of MgFe 2 O 4 nanoparticles reveals their cubic spinel structure, whereas transmission electron microscopy (TEM) analysis confirms the spherical morphology. The magnetic studies of MgFe 2 O 4 nanoparticles show the superparamagnetic behavior. The MgFe 2 O 4 nanofluid exhibits non-Newtonian shear thinning behavior. The viscosity values are fitted with Einstein, Wang, and Chen models. The effective thermal conductivity data of MgFe 2 O 4 nanofluids is compared with Hamilton-Crosser model. The enhancements in viscosity and thermal conductivity with respect to concentration and temperature are investigated. A quantitative comparison of enhancement coefficients of viscosity and thermal conductivity is made to understand the heat transfer performance of MgFe 2 O 4 nanofluids. From the enhancement ratio, it is proved that the prepared MgFe 2 O 4 nanofluids have enhanced heat transfer efficiency. Unlabelled Image • Aqueous MgFe 2 O 4 nanofluids of various concentration are synthesized through a two-step method. • Long-term stability is achieved through steric stabilisation. • Viscosity and thermal conductivity enhancements are analyzed. • Heat transfer performance is evaluated from the enhancement coefficients of viscosity and thermal conductivity. [ABSTRACT FROM AUTHOR]

Novel CoZnO2 and SnO2 doped CoZnO2 nanocomposites (NCs) were synthesized by the co‐precipitation method successfully and analyzed using UV‐Vis, FT‐IR, XRD and SEM analysis etc. The UV‐Vis studies confirmed the absorption values of CoZnO2 and SnO2 doped CoZnO2 at 359 and 365 nm respectively and the obtained FT‐IR peaks at 569 and 538 cm−1 revealed the presence of metal‐oxygen bonds successfully. The crystalline size was found to be 21.46 and 40.35 nm. In SEM analysis, CoZnO2 showed the densified un‐uniform particles whereas SnO2 doped CoZnO2 NCs seemed to be bunch of particles combined together. The synthesized NCs have proved the photocatalytic property by confirming the degradation efficiency of 72.22 and 82.22 % against methylene blue (MB) under sunlight irradiation as natural source at the time interval of 120 mins. It is revealed by the enhancement in the reduction of 4‐nitrophenol by changing the parameters and the efficiency percentage of 89.46 and 94.52 % at 18 and 16 mins respectively. The adsorption study was carried out by changing different concentrations of targeted pesticide like glyphosate and the percentage (%) efficiency was calculated to be 90.90, 83.53, 78.49 %, and 91.02, 88.23, 80.64 % for CoZnO2 and SnO2 doped CoZnO2 effectively. The high inhibition against DPPH was found to be 42.7 and 53.7 % at 500 μg mL−1 and the maximum zone of inhibition was found to be 22 mm against to 240 μg mL−1 of E. coli. Therefore, the current study proposed that the CoZnO2 and SnO2 doped CoZnO2 have good capability for bio‐chemical catalytic applications. [ABSTRACT FROM AUTHOR]

Background: Infection control guidelines recommend implementation of standard and transmission-based precautions to control multidrug resistant organisms (MDROs) within the hospitals. However, gaps between evidence-based guidelines and practice of contact precautions in the developing world were not assessed. We report the practices of contact precautions in South Indian hospitals. Methods&Materials: A survey and nonparticipant observation study was carried out during October 2015, using a questionnaire on contact isolations such as availability of policy on contact isolation, isolating in a single room/cohorting in ward, displaying isolation sign on the entrance of the room, availability of gowns, gloves, and hand rubs outside the room and monitoring the adherence of policy by health care workers entering the room. Results: During study period contact isolation practices of 20 institutions were observed. Policy on contact isolation was there in 50% of the hospitals, other results are shown in table-1 below. Conclusion: Despite fifty percent availability of contact isolation policy, there is big gap existing in implementing the policy in South Indian hospitals. Our findings suggest that there is a need for regular auditing the practices of contact isolation policy is urgently required. [ABSTRACT FROM AUTHOR]