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The molybdate-incorporated hydrotalcite-type α-Ni(OH)2 catalysts were prepared by the post-synthesis method. The synthesized catalyst was thoroughly studied using several physicochemical characterization methods. The catalytic activity of the material was studied on biomass model compounds such as anisole hydrotreating and the oxidation of iso-eugenol. The catalyst shows a significant conversion for the anisole hydrotreating in vapour phase conditions, yielding a steady-state conversion of 30% even after 10 h of time-on-stream (TOS). The primary product was benzene, with other products, viz., methyl anisole, methylcyclohexane, and toluene, as minor components. The catalyst also has the potential for iso-eugenol oxidation and shows 76.1% conversion with 75.5% selectivity for vanillin at 100 °C, 5 h. Molybdate-incorporated hydrotalcite-type α-Ni(OH)2 catalysts have the potential for oxidation of iso-eugenol to vanillin in the presence of an oxidant in a liquid phase and hydro-deoxygenation in the vapour phase under a hydrogen atmosphere. [ABSTRACT FROM AUTHOR]

In this work, thin films of molybdenum-doped CdO were prepared by spray technique from solutions with varied aging times. The structure of (1 1 1) preferentially grown films is cubic. Variation of crystallite size from 47 to 67 nm takes place with solution aging. Improvement in morphology is observed with aging. Increased transparency and Eg narrowing was realized with aging. The CdO:Mo film from 3-days aged solution exhibits a maximum transparency of 87%. With aging, resistivity decreases and a minimum value of 0.28 × 10–3 Ω-cm was realized with three days aging. Reverse saturable absorption (RSA) effect was realized from the Z-scan studies. Third order NLO susceptibility increases with solution aging. With a negative nonlinear refractive index and a high nonlinear absorption, it was confirmed that the aged films may be used as an optical limiter for laser radiation with self-defocusing. [ABSTRACT FROM AUTHOR]

Recent advances in the field of digital technology have enabled the expansion of the business market to a new level. Digital business markets encompass eminent features like increased transparency, enhanced customer relationship, flexible business targets, customer participation, etc. It aids in enhancing traditional business quality by bridging the relationship between the suppliers and the customers. The massive development of internet technology in recent years has largely contributed to the emergence of digital business. The digitization of the business world helps small and medium enterprises create a new digital network, which allows overcoming large enterprises' dominance. Since small and medium enterprises play a major role in determining a country's economy, the digital market's emergence and development are very important. The self-organizing capability of the digital market is the main advantage for newly emerging enterprises. Recently, the Covid-19 pandemic has resulted in customers' migration from offline shopping to the online market. These changing business models mandate the need for policies and control mechanisms. Using these policies, digital business projects are developed using an open environment using which the small and medium enterprises can interact with each other. These policies and control mechanisms outline the rules to be followed to avoid the current digital market issues. These policies must be designed to improve and ensure the welfare of future digital business systems. Thus, this paper aims to explore the policies associated with regulating and promoting the digital business economy. [ABSTRACT FROM AUTHOR]

Good healthcare systems are crucial to the socio-economic growth of a country. In the current scenario, with a rapidly growing population, it is not always possible to find good hospitals nearby which has beds and doctors available, especially in times of emergencies. However, no reliable hospital recommendation system exists which compute these parameters and suggests hospitals. The proposed model utilizes neural networks to recommend hospitals based on hospital ratings, doctors available and distance to ensure that in time of emergencies, because crucial time is not wasted and the people can go to the best suited hospital. A comparative study among different neural network models were carried out in terms of accuracy and computing time. The most efficient model was chosen to be implemented in the final recommendation system. The dataset used to train the neural network models was the Hospital rating dataset provided by the Centers for Medicare and Medicaid services available on Kaggle. A real-time database has been made in Google Firebase, which contains information about hospitals like location, ratings, doctors and beds available. An attendance system for doctors has also been designed using Radio Frequency Identification (RFID) cards and NodeMCU. A web-application has also been designed where the user can obtain the name, address and phone number of the recommended hospital or hospitals. [ABSTRACT FROM AUTHOR]

Photocatalytic, magnetic and antimicrobial properties of barium zirconate (BaZrO3) perovskite green synthesized using Plectranthus amboinicus (P. amboinicus) and Ocimum sanctum (O. sanctum) leaf extracts has been summarized here. Confirmation of cubic structure with (1 1 0) preferential growth has been arrived from the XRD studies. The occupancy of magnetic metal ions such as Cu2+, Ni2+, Mn2+ and Co2+ on the octahedral A and B sites makes P. amboinicus and O. sanctum leaf extract–mediated BaZrO3 paramagnetic and ferromagnetic, respectively. Antimicrobial studies performed against Pseudomonas aeruginosa bacteria justifies that the green synthesized samples exhibited good inhibition on its growth. Photocatalytic activity of the green synthesized BaZrO3 nanoparticles was explored by Congo red dye degradation under ultra-violet illumination. Increased degradation efficiency and photostability were realised for O. sanctum leaf extract–mediated BaZrO3. The obtained results infer that the O. sanctum leaf extract–mediated BaZrO3 perovskite is well suited for soft magnetic materials, biological and catalytic applications. [ABSTRACT FROM AUTHOR]

In this present study, two dissimilar aluminum alloys of AA5052-H32 and AA6061-T6 were joined in butt joint configuration to examine the influence of process parameter on tensile strength and microstructural examination. Tool profiles such as square, cylinder, triangle with welding speeds like 30, 60, 80 mm/min and tool rotational speeds such as 800, 950, 1100 rpm were selected as process parameters for friction stir welding. Among the various tool profiles, square pin profile produced good pulsating action of 60 pulses and having max SV/DV ratio of 2.3 which helped to produce higher tensile strength. Microstructural examination on the nugget zone revealed that higher welding speed causes some cracks in the nugget zone due to insufficient stirring of the materials. Microhardness examination reveals that HAZ of both zones exhibited lower hardness on both sides. Nugget zone at centre was measured with increased hardness than BM of AA5052 and lower than AA6061. SEM fractography revealed that the specimens were failed in ductile mode and specimens failed at higher tensile strength observed with high ductility. Taguchi optimization technique has been implemented and the process parameters combination was optimized for higher tensile strength. The dissimilar joints fabricated at optimized process parameters produced maximum tensile strength of 181 MPa are as follows: Tool Profile—Square, Tool-Rotational Speed—1100 rpm and Welding speed—60 mm/min. [ABSTRACT FROM AUTHOR]

Solvent volume has profound influence on the structural, morphological and optoelectronic properties of spray deposited thin films. In this work solvent volume (20, 30, 40, 50 and 60 mL) impact on the optoelectronic properties of spray deposited molybdenum doped cadmium oxide (CdO:Mo) has been reported. XRD reveals cubic crystal structure of the CdO:Mo thin films. Crystallite size increases with solvent volume up to 50 mL and for the 60 mL it decreases. SEM images show cauliflower shaped grains. EDX spectra revealed Cd, Mo and O in all the films. Thickness dominated the UV–Vis-NIR properties of the films. The increased band gap values with increased solvent volume are attributed to the Burstein-Moss effect. The 50 mL solvent volume coated film exhibited increased transparency, low sheet resistance (21.6 Ω/□), low resistivity (0.93 × 10–3 Ω-cm) and high figure of merit value (1.15 × 10–2 Ω−1). Fabrication of a photodiode with p-Si/n-CdO:Mo/Ag heterostructures is done to study its photo response behaviour. [ABSTRACT FROM AUTHOR]

In health care firm, data mining (DM) has an effectual role in predicting the diseases. Today, diabetes is the chief global health issue. Several algorithms are introduced for predicting the diabetes disease and its accuracy estimation. Yet, there is no effectual algorithm for providing the severity of diabetes in respect of ratio which interprets the impact of diabetes on different organs of the human body. To overcome such drawbacks, predictive and risk level classification of diabetes patients using DLMNN and Naïve Bayes (NB) classification methods is system model. This system model system comprises 2 phases namely, phase-1: diabetic disease prediction model, and phase-2: risk analysis. In phase-1, the patient data are taken as of the dataset. Then, from this patient dataset repeated data are removed using HDFS Map Reduce (). Next, as the preprocessing stage, the missing attributes are replaced by averaging the considered data. After that, from the preprocessed data the disease is predicted using DLMNN classification method which results in obtaining the diabetic patient data. Then, the diabetic patient data are sent to phase-2. In phase 2, the missing attributes are replaced using the same average method. Next, the patient data is sorted centered on age utilizing recursive K-means clustering algorithm. Finally, the clustered patient data is classified using the NB classifier algorithm. Experiential results contrasted the system model modified deep learning algorithm with the existing IKMC algorithm in rapports of precision, accuracy, F-measure, and recall. The outcomes confirmed that the system model diabetes prediction and analysis model shows better results on considering the existent methods. [ABSTRACT FROM AUTHOR]

In this paper, we propose efficient food traceability management techniques using the Internet of things and derive a solution for data transmission. The enhanced Petri net model is utilized for food traceability using the improved period data. The application of the food traceability is used to maintain the automation, minimized cost and reduced system complexity. The primary parameter for this system is the food transportation from the producer to the customer. The Internet of Things is utilized to connect the producer to the customer with a smart transportation system. A low-cost solution is obtained using the IoT based food traceability. The application of the food traceability is used to maintain the automation, minimized cost and reduced system complexity. The Enhanced Petri Net model is simulated and the experimental results proved that the proposed Enhanced Petri Net algorithm is more efficient for food traceability management Techniques compared to the K-means and SOM methods. [ABSTRACT FROM AUTHOR]

The present study focuses on the suitability of CdO thin films towards optoelectronic and spintronic devices through (Zn + Co) co-doping. Para to ferromagnetic transition mediated by oxygen vacancies takes place in the CdO:Zn thin films through Co doping which was acknowledged from the photoluminescence studies. Defect level peaks observed in the PL spectra at 411, 460 and 494 nm are associated with metal interstitials (Cdi, Zni, Coi), singly ionized oxygen vacancies (Vo+) and oxygen vacancies (Vo), respectively. The deep-level or trap state emission due to the ionized oxygen vacancies is observed at 521 nm. XRD analysis indicate that the undoped, Zn-doped (CdO:Zn) and (Zn + Co) co-doped CdO thin films have cubic structure with (1 1 1) plane being the preferential one. The crystallite size of pure CdO decreases with Zn-doping and with Co co-doping it increases. Cauliflower shaped nanostructures are evinced for the (Zn + Co) co-doped films. Increased optical transparency and decreased sheet resistance were observed for the (Zn + Co) co-doped films. Increased Haacke's quality factor observed for the (Zn + Co) co-doped films confirmed their potential for optoelectronic devices. [ABSTRACT FROM AUTHOR]

CdO–TiO2–CuO ternary composite has been synthesized by a precipitation method and its photocatalytic and magnetic properties studied. The results are compared with its single and binary entities and reported materials. Peaks related to cubic, anatase, and monoclinic CuO, TiO2, and CuO were observed in the x-ray diffraction pattern of the ternary composite. Energy-dispersive x-ray and x-ray photoelectron spectroscopy analyses confirmed the presence of Cd, Ti, Cu, and O in the ternary composite, and their uniform distribution was well confirmed by mapping images. The optical bandgap values of CdO, TiO2, CdO–TiO2, CuO, and CdO–TiO2–CuO nanoparticles were found to be 2.48 eV, 3.14 eV, 2.72 eV, 1.69 eV, and 2.32 eV, respectively. The ternary composite exhibited a maximum rhodamine B (RhB) dye degradation efficiency of 91.2% under visible-light illumination. The removable and regenerable nature of the ternary composite catalyst is due to its enhanced ferromagnetic behavior. Recycling tests confirmed the more stable nature of the synthesized ternary composite catalyst. [ABSTRACT FROM AUTHOR]

Improved photocatalytic activity through cobalt (Co) doping has been reported for Al2O3 nanoparticles in this paper. Undoped and Co-doped Al2O3 nanoparticles have been synthesized via a precipitation method. Pure and Al2O3 nanoparticles exhibit a monoclinic crystal structure. The optical bandgap decreases from 3.80 eV to 3.64 eV with Co doping. Due to the red shift in the bandgap, the recombination rate of photo-induced electrons and holes decreases in the doped catalysts which improved their efficiencies against the degradation of rhodamine dye. A remarkable degradation efficiency of 95.45% is evinced for the 4 wt.% Co-doped Al2O3 catalyst and this was well acknowledged from its decreased crystallite size, decreased bandgap and increased photosensitivity values. An increased degradation rate constant value of 0.96649 min−1 observed for the 4 wt.% Co-doped Al2O3 catalyst also confirms this. The results obtained indicate that the Co-doped Al2O3 nanoparticles are potential candidates as visible light catalysts with remarkable degradation efficiencies against toxic dyes. Also, the realization of ferromagnetism confirms the regenerable and reusable quality of the Co-doped Al2O3 catalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic performance of precursor solution-aged undoped, Zn-doped CdO (CdO:Zn) and Ag-doped CdO (CdO:Ag) thin films has been reported in this paper. Perfume atomizer is adopted to deposit the films. CdO, CdO:Zn and CdO:Ag thin films exhibit cubic crystal structure. The crystallite size values were 34, 31 and 27 nm, respectively, for the CdO, CdO:Zn and CdO:Ag thin films. In the EDX spectra of the CdO:Zn and CdO:Ag thin films, Zn and Ag were observed along with Cd and O. The CdO:Zn and CdO:Ag thin films exhibit increased transparency and widened band gap values. PL spectra showed peaks related to oxygen vacancies for all the films. Reduced resistivity was evinced for the CdO:Zn and CdO:Ag thin films. The degradation efficiencies of the CdO, CdO:Zn and CdO:Ag thin films against methyl orange after 75 min light exposure were 76.4, 84.3 and 90.4%, respectively. The CdO:Zn and CdO:Ag catalysts exhibit satisfactory stability with better reusable nature and are suitable for the effective treatment of organic toxic dyes. [ABSTRACT FROM AUTHOR]

Fe-doped SnS2 (SnS2:Fe) nanopowders were synthesized by cost effective chemical method and characterized by thermo gravimetric-differential thermal analysis, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and vibrating sample magnetometer techniques. The photocatalytic activity was evaluated for the degradation of congo red dye under visible light irradiation. XRD studies indicate that both the undoped and doped SnS2 nanopowders exhibit hexagonal crystal structure with a strong (1 0 1) preferential growth. Nanosized grains are evinced from the TEM images. XPS spectra confirmed the presence of Fe in the doped samples. Photodegradation efficiency increased with increase in Fe doping concentration and the SnS2:Fe nanopowder with 10 wt% Fe doping concentration exhibits a maximum efficiency of 93.94% after 180 min light irradiation. Ferromagnetic ordering of pure SnS2 improved with Fe doping. The outcome of the results indicated that Fe-doped SnS2 nanopowders are well suited as diluted magnetic semiconductor and also can be used as an efficient photocatalyst. [ABSTRACT FROM AUTHOR]

Cobalt-doped PbS (PbS:Co) thin films were grown on glass substrates via a cost effective spray technique using perfume atomizer. The effect of Co doping concentration on the thermal behavior, structural, optical and magnetic properties of PbS thin films was investigated and the results are reported in this paper. TG-DTA studies confirm that the thermal behavior of pure PbS is strongly influenced with Co doping. X-ray diffraction patterns reveal that both the undoped and doped PbS thin films exhibit face-centered cubic crystal structure with a strong (2 0 0) preferential growth texture. The increase of Co doping concentration tends to increase the band gap of pure PbS from 2.24 to 2.46 eV which may be attributed to quantum confinement effect. Undoped PbS thin film exhibit paramagnetic behavior at room temperature which becomes ferromagnetic with Co doping. From the results obtained it is observed that the PbS thin films doped with 3 wt% Co concentration exhibit better magnetic properties. [ABSTRACT FROM AUTHOR]

PbS nanopowder doped with Ag+ ions was synthesized by a cost effective chemical method using lead nitrate, thiourea and silver nitrate as the precursor salts. Thermogravimetric-differential thermal analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, Fourier transform infrared (FT-IR) spectroscopy, photoluminescence were used to characterize the samples. XRD studies reveal that all the samples exhibit cubic crystal structure with a strong preferential growth along the (2 0 0) plane. Cauliflower shaped nanostructures are visible from the SEM images. FTIR studies confirm the presence of peaks related to heteropolar diatomic molecule of lead sulfide for all the samples. The photocatalytic activity of pure PbS got enhanced with silver doping and PbS:Ag nanopowders could be used as an efficient photocatalyst for the degradation of methyl orange. Ag+ ions seem to dominate the antifungal efficiency of pure PbS. The results obtained confirm that PbS:Ag nanopowders are well suited for biomedical applications. [ABSTRACT FROM AUTHOR]

A cost effective chemical route is used to synthesize pure PbS, SnO and PbS-SnO nanocomposites. The thermal behavior, magnetic, photocatalytic and antifungal properties of the synthesized samples were investigated. The composite becomes well crystallized above 284 °C. Diffraction peaks related to PbS and SnO were observed in the XRD pattern of the composite. EDX spectrum confirms the presence of the elements Pb, S, Sn and O in the composite. Functional groups related to Pb-S and Sn-O is evinced from the FTIR spectrum. Photoluminescence studies confirm that the PbS-SnO nanocomposite has optical band gap value intermediate between pure PbS and SnO nanopowders. Photocatalytic studies confirm that the PbS-SnO composite have better degradation efficiency against methyl orange compared to that of pure PbS and SnO nanopowders. Enhanced ferromagnetic behavior is observed for the composite. The composite had better antifungal efficiency against A. niger fungus strain. [ABSTRACT FROM AUTHOR]

NiFeO and LiNiFeO/NiFeO nanocomposite samples are prepared using citric acid and urea assisted combustion process. The prepared pristine and nanocomposite samples are characterized by using powder X-ray diffraction, Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy techniques. The effect of LiNiFeO on the LiNiFeO/NiFeO crystallite size and associated strain is calculated using Williamson-Hall plot. The effect of LiNiFeO on the electrical and dielectric properties of the composite samples are analyzed using AC-impedance spectroscopy. The prepared composite materials exhibit mixed electrical conduction behavior, and the conduction is due to lithium ion migration as well as electron hopping between Fe and Fe ions in the spinel structure. The conductivity gradually increases and attains maximum upon lithium ion inclusion in the composite. The further increment of lithium ion doping decreases the conductivity. [ABSTRACT FROM AUTHOR]

Al-doped SnS (SnS:Al) nanopowders with 0, 5, 10 and 15 wt% Al concentrations were synthesized by a simple soft chemical route. The powders are characterized by XRD, SEM, TEM, EDX, FTIR, UV-Vis-NIR and PL studies. Thermal behavior, magnetic and antifungal properties of the synthesized powder samples was studied and the results obtained are being reported in this paper. TG-DSC studies confirm that both the undoped and doped samples become well crystallized above 320 °C. XRD studies confirm that both the undoped and doped SnS nanopowders exhibit hexagonal crystal structure with a strong (1 0 1) preferential growth. Lattice parameters of pure SnS experience contraction with Al doping. EDX spectra confirm the presence of Al in the doped samples. The PL peaks at 433 and 485 nm confirmed the presence of sulfur vacancies in the synthesized samples. Ferromagnetic behavior is observed for the SnS:Al nanopowders. Improved antifungal efficiency is observed for the doped samples. [ABSTRACT FROM AUTHOR]

Stabilization of a single rotary inverted pendulum (SRIP) system is a benchmark nonlinear control problem. Inherent instability of SRIP in upright position and the presence of modelling uncertainty pose a challenge for control engineers. Sliding-mode control (SMC) is the most widely accepted robust control technique. Various versions of SMCs to stabilize SRIP have been reported in literature. Advantages of SMC come at the cost of chattering of input, which inhibits its usage in many practical applications. Several works have been done to reduce the chattering in SMC. Application of fuzzy logic in SMC to reduce chattering has been analysed extensively in the literature. Even though implementation of fuzzy SMC (FSMC) in theory/simulations completely eliminates chattering, practical implementation of FSMC does not reduce chattering to zero. In this paper, a filtered FSMC is proposed, which filters the high frequency component in the system input. Experimental results of SMC, FSMC and a fuzzy sliding-mode controller with filter (FSMCF) are given in this paper. Results indicate that filtering the output of FSMCF reduces the chattering effect in the system without affecting the closed loop dynamics. [ABSTRACT FROM AUTHOR]

This paper reports the results obtained on the thermal behavior, structural, morphological, optical and magnetic properties of spray deposited Sr-doped CdS (CdS:Sr) thin films. XRD studies confirm that both the undoped and doped films exhibit hexagonal crystal structure with a strong (0 0 2) preferential growth. The 2θ value of pure CdS shifts towards lower Bragg angle with Sr doping. The microstructural features were examined by SEM, TEM and compositional analysis was carried out by energy dispersive spectroscopy (EDS). Decreased grain size is observed from the TEM images. Super paramagnetic and ferromagnetic orderings was observed for the Sr-doped CdS films. Increased transparency and widened band gap values was observed for the doped films which was attributed to Burstein-Moss (BM) effect. [ABSTRACT FROM AUTHOR]

In order to prepare SrFeO materials, the raw materials, SrCO and FeO were annealed with different alkali metal chlorides such as LiCl + NaCl, LiCl + KCl, LiCl + CsCl, NaCl + CsCl, and KCl + CsCl as the flux at 1200 °C for 5 h. The structural features of SrFeO materials prepared without flux have been compared. The phase formation and the properties of the SrFeO materials are sensible to the fluxes used in the synthesis process. The fluxes, NaCl + CsCl, and KCl + CsCl produced good quality nanocrystalline SrFeO materials, whereas the LiCl + NaCl, LiCl + KCl, and LiCl + CsCl flux reaction mixtures yielded mixed phase materials. The NIR reflectance of the present series materials varies regardless of the fluxes used in the synthesis. Relatively high NIR reflectance is noted for the KCl + CsCl flux annealed SrFeO materials even though KCl + CsCl and NaCl + CsCl fluxes yielded single phase SrFeO materials. A typical hard ferromagnetic hysteresis loop opening is observed at room temperature (300 K) for the NaCl + CsCl and KCl + CsCl fluxes annealed SrFeO materials. Plate-like hexagonal grains with different size are observed in the microstructural images of the NaCl + CsCl flux annealed SrFeO materials. The molten salt flux method employed in the present work is simple and efficient for the production of phase pure SrFeO materials using NaCl + CsCl, and KCl + CsCl as the flux, that are worth for different high-tech applications including satellite communications, magneto-optical recording, data storage, and electrical and microwave devices. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis of undoped PbS and PbS-CdO nanocomposites by a simple soft chemical route. The thermal behavior, structural, morphological, optical, magnetic and antimicrobial properties of the synthesized samples was studied and the results are reported in this paper. The undoped PbS and PbS-CdO nanocomposite exhibit polycrystalline nature with cubic crystal structure. The crystallite size values of the PbS and PbS-CdO nanocomposites estimated using Scherrer formula were found to be equal to 24.96 and 21.89 nm respectively. TG-DTA analysis shows that the PbS-CdO nanocomposite becomes well crystallized above 400 °C. Peaks related to PbS and CdO were observed in the FTIR spectra of the composite. Magnetic studies confirm that the PbS-CdO nanocomposite exhibit ferromagnetic ordering in the form of S-shaped loop. Enhanced antibacterial and antifungal activities were observed for the PbS-CdO nanocomposite. [ABSTRACT FROM AUTHOR]

In this work, a novel combustion synthesis of nanocrystalline MgFeO materials using hexamethylenetetramine as a fuel is reported. The properties and features of as-prepared MgFeO materials were evaluated by X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometer, UV-vis and Fourier transform infrared spectroscopic techniques, and field emission scanning electron microscope. The as-prepared MgFeO materials crystallized in cubic spinel phase with an average crystalline of 26.34 and 21.54 nm for the samples obtained at pH = 1 and 10, respectively. It is evident from the room temperature (300 K) field (±15 kOe) dependence magnetization measurements that the saturation magnetization of the MgFeO materials is 25.86 emu/g and 9.98 emu/g for pH = 1 and 10, respectively. For the as-prepared MgFeO materials, the agglomeration of fine particles is seen through a micro-image under higher magnification. The FT-IR spectra reveal a typical metal-oxygen absorption band at ∼568 cm for the as-prepared MgFeO materials which suggest the intrinsic stretching vibration of the metal (Fe-O) at the tetrahedral site. [ABSTRACT FROM AUTHOR]

Steel coils are welded end to end for processing in a continuous galvanizing line of a cold rolling mill. Failure of the welds in the line during processing results into mill stoppages causing huge production downtime. An automated ultrasonic-based non-destructive measurement system for assessing the weld integrity of 0.6-2-mm-thick steel sheets immediately after welding is described. The system was designed to detect any physical weld defects, viz., lack of fusion, expulsion, cracks, etc., which compromises the integrity of weld leading to its failure in the processing line. A high-frequency ultrasonic probe with an integrated water chamber was designed for enabling high-speed non-contact automated inline inspection of the weld considering the limited inspection time available in the mill (40 s). A prototype scanning system was made using the developed ultrasonic probe which was successfully able to detect the weld defects formed in actual plant samples. [ABSTRACT FROM AUTHOR]

The nanocrystalline SrFe O materials were prepared by a sol-gel auto-combustion method using different fuels such as citric acid, dextrose, aniline, and hexamine. The combustion product obtained from all the fuels except from that of aniline show a single phase of SrFe O materials upon annealing at 1000 C/2 h. The combustion product obtained from aniline as fuel shows SrFe O as the main phase with α-Fe O as impurity. No notable change in lattice parameters is observed due to variation in fuels for SrFe O materials. With a little change in the NIR relative reflectance (72-85 %) on fuels, the different SrFe O materials display high NIR reflectance in the wavelength range, 1500-2500 nm. The photoluminescence emission spectra of SrFe O materials reveal a broad emission peak at ∼350 nm which is reminiscent to the Ba-based hexaferrite, BaFe O . The FESEM images expose quite dissimilar morphology for the various fuels used in the synthesis of SrFe O materials. Hysteresis loops for all the nanocrystalline SrFe O materials observed under the applied field of ±1.5 T at room temperature exhibit hard ferromagnetic property. The SrFe O materials produced from glycine and aniline as fuels exhibit highest and lowest M values of 61.3 and 50.5 emu/g, respectively. [ABSTRACT FROM AUTHOR]

This paper outlines the effect of (Mn + F) double doping on the structural, morphological, optoelectronic, magnetic and antibacterial properties of CdO thin films. Undoped CdO, Mn-doped CdO and (Mn + F) doubly doped CdO films exhibit face-centered cubic structure with a strong (1 1 1) preferential growth. Crystallite size value of the undoped film estimated using the Scherrer formula decreases with Mn doping and with double doping it increases. Cauliflower shaped nanostructures are evinced from the SEM images. Increased optical transparency is observed for the doubly doped films. The optical band gap value of the Mn-doped CdO film is found to be red shifted and for the (Mn + F) doubly doped films it is blue shifted which may be attributed to the Moss-Burstein effect. Ferromagnetic ordering is observed for the doped films. The doped films show increased antibacterial efficiency against K. pneumonia a gram −ve bacteria. The obtained results infer that the CdO films doubly doped with Mn (cationic) and F (anionic) ions exhibited better optical, electrical, magnetic and antibacterial properties. [ABSTRACT FROM AUTHOR]

This paper is focused on the results obtained on the structural, morphological, optoelectronic, photoconductive properties and antimicrobial activities of Al-doped PbS nanopowders synthesized by a simple soft chemical route. All the samples exhibit face-centered cubic structure with a (2 0 0) preferential orientation. The lattice constant values experience shrinkage with Al doping. Spherical shaped nanograins are visible from the TEM images of both the undoped and doped nanopowders. Optical band gap of pure PbS is found to increase from 1.91 to 2.04 eV with Al doping which may be attributed to quantum confinement effect. Photoconductivity is found to increase with Al incorporation making the synthesized nanopowders suitable for photoconductive sensing applications. Antifungal activities of the prepared samples were carried out against three fungi strains. It is found that the antifungal efficiency of the PbS nanopowders is improved with Al doping which make them suitable as antimicrobial agent against pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

This paper reports the eco-friendly synthesized BaFeO phase materials by a molten salt flux approach and their experimental findings. The reaction mixture (BaCO and Fe O ) annealed with the mixture of salt (NaCl:KCl) flux yielded good quality nanocrystalline hexagonal ferrite BaFeO phase materials. The plate-like hexagonal-shaped BaFeO phase morphology with random particle sizes of ∼370 to 940 nm is seen for the good quality flux-annealed sample. The room-temperature magnetic hysteresis loop of the BaFeO sample exhibits hard ferromagnetic saturation magnetization ( M ) of 50.23 emu/g at 15 kOe, and coercive field ( H ) is 3500 Oe. The determined energy bandgap ( E ) is found to be 3.58 eV for the BaFeO phase material. The Fourier transform infrared (FT-IR) spectral features confirm the presence of Fe-O and Ba-O bonds in the flux-synthesized BaFeO materials. The photoluminescence (PL) emission peak (∼360 nm) intensity of BaFeO materials varies regardless of annealing temperatures. The different salt flux-synthesized BaFeO materials appear as brown- and dark gray-colored powders that can be applied as a ceramic color pigment due to its high NIR reflectivity. [ABSTRACT FROM AUTHOR]

The nanocrystalline BaFeO powders were obtained from citrate sol-gel combustion-derived powder upon annealing at 800-1100 °C, and explored their structural, micro-structural, optical and magnetic properties. The thermal decomposition of citrate sol-gel combustion product was verified by means of thermogravimetric and differential thermal analysis. Structural identification of the citrate sol-gel combustion powder and annealed samples were investigated by powder X-ray diffraction. Though the combustion product exhibits cubic spinel phase material, the annealed powder yields good quality nanocrystalline hexagonal BaFeO phase materials. The thin plate-like flakes morphology with random particle sizes of ~100-200 nm with slightly agglomerated particles of BaFeO phase is analyzed by high resolution scanning electron microscopy for the good quality annealed sample. Photoluminescence emission spectrum of BaFeO material reveals broad emission peak at ~360 nm under the excitation wavelength of 270 nm. Interestingly, the near infrared relative reflectivity of the nanocrystalline BaFeO materials obtained by citrate sol-gel synthesis method is higher than the nanocrystalline BaFeO materials obtained by mechano-thermal and co-precipitation method. The present dark brown colored BaFeO materials can be applied as a ceramic color pigment which includes several applications. The room temperature magnetic hysteresis loop of the annealed BaFeO sample exhibits a ferromagnetic saturation magnetization, M of 55.774 emu/g at 15 kOe. [ABSTRACT FROM AUTHOR]

We report here a simple solution combustion synthesis of nickel oxide (NiO) nanoparticles by using urea as a fuel and nickel nitrate as an oxidizer. The structural, morphological, optical, and magnetic properties of NiO nanoparticles were investigated by X-ray diffraction (XRD); highresolution scanning electron microscopy (HRSEM); Fourier transform infrared (FT-IR), nearinfrared (NIR), and UV-vis spectroscopic techniques; and vibrating sample magnetometer. The combustion-synthesized NiO nanoparticles have a cubic structure with an average crystalline size of ∼8 nm without any impurity. The agglomeration of fine particles with particle sizes in the range of 19.5 ∼22.4 nm is seen by HRSEM images. The FT-IR spectrum of NiO nanoparticles reveals that an absorption band at ∼493 cm is due to the bending vibration of NiO phase. The NIR spectrum exhibits poor NIR reflectivity of the combustion product, NiO. The as-prepared combustion product was black in color in contrast to the usual light green color. The room-temperature magnetization of the as-prepared NiO nanoparticles reveals an antiferromagnetic behavior. [ABSTRACT FROM AUTHOR]

The physical properties of high-pressure synthesized polycrystalline Cu(ReMoCa)SrO samples are reported in this article to attract the scientific community. The present system undergoes a structural phase transition from cubic symmetry (for x=0, 0.1) to tetragonal for 0.2≤ x≤0.4 and again cubic perovskite structure for x=0.5 and 0.6. The pristine compound ( x=0) undergoes a ferromagnetic (ferrimagnetic) transition with high T∼460 K. Neither the Curie temperature nor the effective magnetic moment is enhanced upon Mo substitution. The mechanism of the suppression of ferromagnetism in the present system is discussed assuming a localized electron system which is reminiscent of W substitution (Balamurugan et al. in J. Appl. Phys. 101:09N501, ). The temperature dependence of electrical resistivity, ρ decreases with x=0-0.4 and then increases for x=0.5 and 0.6. Though the suppression of ferromagnetism in the present system is similar to W-substitution, interestingly the former one (Mo) shows different results on structural and transport electrical properties which urge for further studies. The interesting aspect of the present work is for x=0.6, the specific heat data shows significant electronic contribution, whereas the resistivity measurement reveals insulating behavior. [ABSTRACT FROM AUTHOR]

The tocopherols are amphipathic antioxidant synthesized by photosynthetic organisms, which forms the essential component in the human diet. To increase the α-tocopherol content in tobacco, two approaches have been attempted in this study: (1) transgenic approach, by constitutive overexpression of the genes encoding Arabidopsis homogentisate phytyltransferase ( HPT) and tocopherol cyclase ( TC) through Agrobacterium-mediated genetic transformation; (2) non-transgenic approach, by supplementation of intermediates/precursors of vitamin E biosynthesis like tyrosine, p-hydroxyphenyl pyruvic acid, homogentisic acid (HGA) and phytol in different concentrations and combinations using cell suspension culture system. Molecular analyses by PCR, RT-PCR and Southern hybridization were carried out to confirm the HPT and TC expressing transgenic tobacco lines. The α-tocopherol content in transgenic plants expressing HPT and TC increase by 5.5 and 4.1, respectively, over the wild type. These results indicate that, HPT and TC activities are important in tobacco plants for enhancing the vitamin E content. In the second approach, the supplementation of precursor in cell suspension cultures, i.e., combination of 150 μM HGA + 100 μM phytol, showed the maximum enhancement of α-tocopherol, i.e., 36-fold. These findings clearly imply that enhancement of α-tocopherol levels in tobacco system is possible, if we could modulate the vitamin E metabolic pathway. This is a very useful finding for the large-scale production of natural Vitamin E. Among the two systems tested, cell suspension culture-based system is ideal over the transgenic technology due to its efficiency and no biosafety concerns. [ABSTRACT FROM AUTHOR]

New liquid crystalline polymers containing both fluorescent and photocrosslinking properties with various alkyl chain lengths ( m = 2,4,6,8,10) were prepared by solution polycondensation reaction of 2,6-bis[4-(m-alkoxy)benzylidene]cyclohexanone and (4-phenyl)-2,6-bis (4-chlorocarbonyl phenyl)pyridine in THF using triethylamine as an acid acceptor. The polymers were characterized using various spectral techniques. These polymers were found to be thermally stable up to 377 °C confirmed by thermogravimetric analysis (TGA). Differential scanning Calorimetry (DSC) and polarized optical microscopy (POM) were carried out to study the phase structures and phase behaviors of this series of polymer. Some of the polymers with longer methylene chains demonstrated grainy type nematic LC phases. On irradiation with UV light at various time intervals, the prepared polymers showed different rate of crosslinking depending upon the alkyl chain lengths present in the polymer backbone. In addition, these polymers also show enhanced fluorescent property by the presence of heterocyclic unit in the polymer. [ABSTRACT FROM AUTHOR]

The number of Internet users and the number of web pages being added to www increase dramatically every day. It is therefore required to automatically and efficiently classify web pages into web directories. This helps the search engines to provide users with relevant and quick retrieval results. As web pages are represented by thousands of features, feature selection helps the web page classifiers to resolve this large scale dimensionality problem. This paper proposes a new feature selection method using Ward's minimum variance measure. This measure is first used to identify clusters of redundant features in a web page. In each cluster, the best representative features are retained and the others are eliminated. Removing such redundant features helps in minimizing the resource utilization during classification. The proposed method of feature selection is compared with other common feature selection methods. Experiments done on a benchmark data set, namely WebKB show that the proposed method performs better than most of the other feature selection methods in terms of reducing the number of features and the classifier modeling time. [ABSTRACT FROM AUTHOR]

In order to check the solubility of Zn in the (SrZn)CoO perovskite structure and their research findings, several polycrystalline samples have been prepared under wide extreme synthesis conditions at 6 GPa/1300-1650 °C. While 0.05≤ x≤0.3 compositions revealed single phased cubic structure materials, x>0.3 showed multi-phased materials for (SrZn)CoO system. Like other substituted perovskite cobalt oxide systems (Ca, Y, Ho and Ce), the transport properties of the present materials show rather sizable changes with respect to ' x', although there are insignificant variations in lattice parameter and in Curie temperature, T. All the present samples show soft ferromagnetism with T in the range of 272-285 K for 0.05≤ x≤0.3. The effective paramagnetic moment, P determined from the paramagnetic region decreases upon the substitution of Zn for Sr-site. These P (3.3-2.8 μ/Co) values for 0.05≤ x≤0.3 compositions seem to suggest that the Co lie in intermediate spin (IS) state for the present (SrZn)CoO series, although they are slightly smaller than those expected for IS-Co; P=3.87 μ/Co. The electrical resistivity is found to increase with increase of ' x' for the investigated samples. The temperature and field dependence of both positive and negative magnetoresistance (MR) are noted for the Zn substituted samples. About 5% of -MR is observed for x=0.05 sample around the transition temperature (280 K) under the field strength difference, Δ H=90 kOe. The present research findings are compared with our previous results on different perovskite cobalt oxides. [ABSTRACT FROM AUTHOR]

In this present investigation, both YBaRuCuO and SrReCaCuO perovskite compounds were prepared through high pressure/high temperature (HPHT) synthetic route. The as-prepared samples were structurally characterized by powder X-ray diffraction technique and their magnetic properties were measured. Both compounds crystallized in cubic symmetry with a different space group. The refined lattice parameter for the YBaRuCuO and SrReCaCuO compounds are found to be a=8.332(2) Å with space group, Fm-3m (225) and a=7.967(4) Å space group Pm-3m (221), respectively. The cuprate ordered perovskite compound shows ferromagnetism with high Curie temperature, T at ∼450 K whereas the YBaRuCuO compound reveals mixed magnetic natures below ∼170 K which is complicated by the presence of magnetic order in the Ru and Cu sublattices. Below 170 K, the compound shows two antiferromagnetic-like transitions (in ZFC mode) at ∼135 K and ∼60 K. With a further decrease of temperature (below 60 K), the susceptibility crosses negative (diamagnetic) signal at ∼35 K and shows maximum negative susceptibility at ∼11 K. By decreasing the temperature below 11 K, the negative susceptibility decreases and shows positive magnetic susceptibility at 2 K. In the fc mode curve, the sample shows broad antiferromagnetic like transition at ∼55 K. At low temperature (below 30 K), an increase in susceptibility signal is seen in the fc magnetic susceptibility curve. The magnetic parameters, such as Weiss temperature, θ and the effective paramagnetic moment, p obtained from the linear region of χ( T) plots are found to be −307.25 K and 3.74 μ/Ru, respectively, for the YBaRuCuO compound. The negative sign of θ reveals the antiferromagnetic correlations of the compound. While these studied compounds are already known to the literature, the synthesis method (HPHT) employed for the present YBaRuCuO compound is a new approach and quite different from the routine conventional solid state synthesis approach. [ABSTRACT FROM AUTHOR]

The impact of slightly tuning molar ratio in the starting materials on the physical properties of 1212-type rutheno-cuprate, YSrRuCuO (nominal) samples prepared under four synthesis approaches are reported. Interestingly, all samples clearly show the differences in the physical properties of the samples prepared under different synthetic protocols. However, neither XRD nor EDX reveal any notable differences in the crystal structure or sample composition. All the samples exhibit magneto-superconducting properties ( H=5 Oe) which are slightly varied with synthetic approaches. The high field ( H=10 kOe) temperature dependence of magnetization data shows a sharp ferromagnetic transition around 150 K and all the samples obey Curie-Weiss linear behavior above 180 K. The experimental effective paramagnetic moment for the various samples is in the range of 2.5 and 2.7 μ/Ru which are in line with the literature report. The magnetization, M( H) isotherm curves measured at 5 K and −10 kOe≤ H≤10 kOe conditions reveal weak ferromagnetic-like hysteresis loops for all samples with returning moment ( M) and coercive field ( H), whereas the high field M( H) loops indicate soft ferromagnetic behaviors with magnetic saturation. The saturation moment of the samples is slightly varied with the synthesis approaches. None of the samples showed bulk superconductivity ( $T_{\mathrm{c}}^{R = 0})$ down to 2 K, while all samples show onset transitions ( $T_{\mathrm{c}}^{\mathrm{onset}}$) except the sample prepared by approach-3. The latter approach sample shows semiconducting behavior down to 2 K. The $T_{\mathrm{c}}^{\mathrm{onset}}$ noticed at 34 K, 12 K, and 6 K for the sample prepared by approach-1, 2, and 4, respectively. The nearly linear dependence suggests that hopping conduction is dominant in certain temperature range for all samples. The magneto-transport features of these samples exhibit maximum magnetoresistance (MR) at low temperatures. Remarkably, the sample prepared by approach-1 shows largest −MR about 77% at low temperature 2 K and H=90 kOe which stimulates for further investigations. Among the four synthesis approaches employed in the present study, we can probably suggest that the approach-1 (0.5YO+0.5SrO+1.5SrCuO+0.9RuO+0.6CuO) is the preferable method to achieve the best sample ( in terms of magneto-transport features). [ABSTRACT FROM AUTHOR]

The optimized nominal composition, (RuCu) SrYCuO sample, has been prepared through high-pressure and high-temperature solid-state densification method. The obtained material has been studied by X-ray (laboratory) diffraction powder technique, magnetization and detailed magneto-transport measurements. The title compound indicates bulk magneto-superconducting properties under field strengths of H=10, 100, 500 and 1000 Oe. It shows diamagnetic transition at T=54, 38, 20 and 8 K for H=10, 100, 500 and 1000 Oe, respectively, in the zero-field-cooled susceptibility measurements. The high-field ( H=5 and 10 kOe) molar susceptibility measurements show sharp ferromagnetic transition at ∼150 K with reduced molar susceptibility values. The various field dependence of magnetization, M( H), isotherm curves recorded at constant temperatures (5, 10, 25, 50, 100 and 150 K) indicate ferromagnetic saturation, whereas the MH curves measured at 200 and 300 K conditions reveal the paramagnetic state of the compound. Though the sample showed onset transition temperature, $T_{\mathrm{c}}^{\mathrm{onset}}$, at ∼34 K under different field strengths ( H=0, 10, 30, 50, 70 and 90 kOe), no $T_{\mathrm{c}}^{R=0}$ is seen down to 2 K. Even under relatively low applied field (Δ H=10 kOe) the title compound shows large negative magnetoresistance ( MR) of about 68% at 2 K and increases with increasing the field strength up to Δ H=90 kOe ( MR=77% at 2 K). This value is amazing and probably higher than other 1212 type ruthenocuprates. The title compound which shows little negative MR (about 1%) in the high temperature regions (125-300 K) is not affected much by different field strengths. Among the different fixed temperature MR( H) isotherms, the MR( H) curve measured at 5 K shows maximum negative MR of about 47% at 90 kOe compared to other four ( T=50, 100, 200 and 300 K) MR( H) curves. [ABSTRACT FROM AUTHOR]