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The uses of magnesium and magnesium alloys in various fields impedes earnestly due to the low corrosion resistant and poor high temperature properties. In this present investigation, the two problems has been noticed and solved; firstly immense chemical activity and secondly the Mg alloys chemical activity has been inhomogeneous on its surface. This work tries to solve those problems by superhydrophobic (SHP) layer on AZ91D Mg alloy. The SHP surface on magnesium alloy with an angle of contact for water greater than 150° and a sliding angle lesser than 10° is a excellent water-repelling ability has been obtained. The present results confirm that this form of SHP coating has definite anti-corrosion effect in typical corrosive solution. The presented method is uncomplicated, cost effective, and environmentally friendly and has enormous potential value in the production of a large-scale industry.

Nickel-substituted cobalt ferrite–reduced graphene oxide (NCF-RGO) composite was synthesized using a facile one-pot chemical coprecipitation method. The addition of graphene oxide (GO) leads to the decrease in the size of NCF nanoparticles (< 10 nm) present in the nanocomposite, which plays role in controlling their magnetic and dielectric properties. Nickel with a lower ionic radius compared to cobalt, and its substitution in the composite along with the incorporation of GO, exhibits superparamagnetic properties in the blend. A large magnetization of 51.63 emu/g and a high dielectric constant of 3.92 × 106 (at 100 Hz) were also determined for the nanocomposite. High charge-storing capability and tunable magnetization have been developed in this work. Thus the NCF-RGO nanocomposite finds potential application in flexible magnetic storage devices. Nickel-substituted cobalt ferrite-reduced graphene oxide (NCF-RGO) composite was synthesized via the chemical coprecipitation method. A superparamagnetic transition was exhibited by the composite, with an enhanced dielectric constant of 3.92 × 106 at 100 Hz.

Background Fruit and vegetable consumption has increased due to their tremendous health benefits. However, recent studies have shown that contaminated products may serve as vehicles for foodborne pathogens and harmful chemicals. Therefore, fresh vegetables must be decontaminated before consumption to ensure food safety. Results In this study, the combined decontamination treatment of lactic acid (2.5 mL L-1 ) and ozone (9 mg L-1 ) for 10 min showed better efficacy in the removal of contaminants from fresh vegetables as compared to individual treatments. The combined treatment resulted in a reduction of 1.5-3.5 log CFU of native mesophilic bacteria per gram and 1.6-2.9 log CFU of artificially inoculated Escherichia coli per gram from tomato, cucumber, carrot and lettuce. The combined treatment also removed spiked pesticides, which represent artificial chemical contamination (28-97% chlorpyrifos and 62-100% λ-cyhalothrin residues), from fresh vegetables. No significant difference (P > 0.05) in various sensory attributes of vegetables was observed between untreated and treated (lactic acid and ozone) vegetables. Conclusions The combination treatment provides a novel approach to target two groups of contaminants using a single procedure. The combination treatment can be used as an alternative to currently used decontamination techniques for the supply of safe vegetables to consumers. © 2020 Society of Chemical Industry.

The effect of cerium addition on AZ91 magnesium alloy and its influence on stress corrosion cracking (SCC) were studied using constant load proof ring testing NaCl-K2CrO4 and ASTM D1384 solutions at 70 and 80% of yield stress, respectively. The investigation revealed that the optimum grain refinement of desired phases occurred with 0.5% addition of cerium. The addition levels of cerium above 1.5 wt.% to AZ91 alloy resulted in premature failures due to poor SCC resistance in both solutions (K2CrO4 and ASTM D1384 solutions). The microstructural studies of the experimental alloys were characterized by using optical and scanning electron microscopy. The elemental compositions of cerium-added AZ91 magnesium alloys were studied by energy-dispersive spectroscopy. The results indicate that the mode of SCC failure was found to be transgranular in nature along with secondary cracks containing cleavages which resulted from the hydrogen embrittlement and anodic dissolution phenomena. The AZ91 alloy with 0.5 wt.% cerium exhibits better mechanical properties and high stress corrosion resistance.

As-cast Mg-9Li-3Al-xNd (x = 0-2.0 wt.%, with the variation of 0.5wt.%) magnesium alloys were prepared through casting in electrical induction melting furnace under a controlled inert gas atmosphere. Influences of Nd over the metallography changes and corrosion characteristics of Mg-9Li-3Al alloys have been examined by following techniques are OM, XRD, SEM and potentio-dynamic polarization (PDP) test. The results illustrate that adding Nd modifies the continuous β-Li phases into discontinuous phase by the formation of new precipitates such as Al2Nd and Al11Nd3. Meanwhile, the grain sizes of Mg-9Li-3Al-xNd alloys reduced with respect to the increasing Nd content. PDP results disclose that the Nd addition reduces the corrosion current density (icorr) of Mg-9Li-3Al alloys which can be essentially produced by grain refinemente.

The unreported Brucinium Benzilate (BBA) crystal and hirshfeld surface analysis indicated the influence of intramolecular hydrogen bonding network. The protonation of tertiary nitrogen occurs as it is most basic. The protonated N-H+ proton was observed at 7.08 ppm and the benzilate carbon COO- at 178.41 ppm. Molecular electrostatic potential (MEP) studies indicated the electron-rich and electron-deficient sites in the molecule for understanding BBA interaction with an enzyme. Frontier molecular orbital (FMO) studies indicated that it is thermodynamically stable and HOMO-LUMO energy gap was found to be 4.454 eV. The highest interaction as the energy (322.86 kcal/mol) between tertiary ammonium N(LP) and H+. The compound showed the inhibition of Bacillus cereus and Salmonella typhimurium bacteria. ADMET properties indicated that BBA has drug characteristics in binding plasma protein.

The highly efficient three-phase into five-phase impedance source matrix converters used by gallium nitride (Ga-N) bidirectional switches with high-current and high-breakdown voltage are validated. The dual-gate Ga-N switches act as a single device bidirectional switch; whereas, a traditional bidirectional switch is made up of four modules with two insulated-gate bipolar transistors (IGBTs) and two diodes. Improving system efficiency including the implementation of the insulated gate allows small on-state opposition with secure, current collapse-free operation. The manufactured switches having the capabilities of breakdown voltage of 1340 V and the peak drain current exceeds 100 A are used to develop a three-phase to five-phase impedance source matrix converter which displays a maximum transformation effectiveness of 98% at 1 kW amount produced power with the expectancy that the high-current device can achieve a maximum output power of 10 kW or more. Furthermore, the Ga-N bidirectional switches are likewise free for current conduction commencing voltage balances so that the Ga-N-based matrix converter allows for unimportant size and extremely efficient AC/AC power transformation. So this paper presented the performance of highly efficient three-phase into five-phase impedance source matrix converters used by gallium nitride (Ga-N) bidirectional switches with high-current and high-breakdown voltages.

Due to high vapour pressure at ambient conditions, exposed mercury contributes significant vapour concentration in working atmosphere. Ventilation is a conventional, cheap and very effective method to bring down the concentration of hazardous materials like mercury vapour below permissible limit. In this work a numerical model was developed to obtain intuitive understandings of the spatial distribution of mercury vapors from an exposed surface. The model was validated with experimental data generated using a precinct ventilation system with 8.14% absolute average error. a Validated model was used to study the effect of air flow rate (100–1200 LPM) and impact of architectural design of the containment for fixed exposed mercury surfaceon the final (diluted) mercury concentration. Comparative analysis shows that modification in structural design offers a reduced volume averaged exit mercury concentration and also the reduced peak mercury concentration(Cpeak) in the computational domain. Computational approach outlined in this work can be used to estimate spatial variation of mercury vapor concentration and to locate and quantify regions of high local concentration of mercury in various geometries., Air Pollution; Numerical methods; Mercury; Species transport; ventilation; Engineering; Chemistry; Environmental Science.

Physical properties of graphene-related materials can be tuned by doing chemical modifications in its structure through covalent and non-covalent functionalization. Covalent functionalization of ionic salts on rGO structures changes it’s optical and electronic properties. In this work, pyrrolidone and imidazolium-based ionic liquids namely N-methyl-2-pyrrolidone hydrogensulfate (H-NMP+.HSO4ˉ), 1-butyl-3-methyl imidazoliumtetrafluoroborate (BMIM BF4), 1-butyl-3-methyl imidazoliumtrifluoroacetate (BMIM TFA) and 1-butyl-3-methyl imidazoliummethylsulfate (BMIM MeSO4) were covalently functionalized on reduced graphene oxide through microwave assisted process. Presence of (002) peak in the XRD pattern indicates the reduction of GO and fluorination of rGO prepared by functionalzation with BMIM BF4 was confirmed by a peak (001) appeared at 2θ of 12.73⁰. Red shift of π-π* and blue shift of n-π* transitions in UV-Vis spectrum were due to chemical modification in rGO sheets through IL functionalization. The peaks corresponding to IL were observed in FTIR spectra of synthesized samples. The increase in ID/IG ratio in micro-Raman analysis shows more sp3 bonds were formed during IL functionalization.

Herein, dielectric studies of solvent-cast poly(vinyl alcohol) (PVA) with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) freestanding films are conducted in the frequency range of 100 Hz–1 MHz and temperature ranging from 303 to 453 K. An insulator to semiconducting transition is observed for PVA/PEDOT:PSS blend above 413 K. Existence of two types of conduction mechanism, hopping between nearest neighbor at low-temperature region (303–383 K) and free-band conduction at high temperatures (above 413 K) within PVA/PEDOT:PSS films under the influence of applied field, is observed and supported by electric moduli formalisms. An increase in dielectric constant and a significant reduction in $$\tan \delta$$ values are observed under high temperature and low frequency with the addition of PEDOT:PSS. Greater than 100% Coulombic efficiency and 82% specific capacitance retention at 5000 cycles are observed for 7.5 vol% PEDOT:PSS in PVA working electrode for supercapacitor. Thus, the fabricated films find potential applications in the field of flexible conventional capacitors and as working electrodes for supercapacitor.

Ficus roxburghii, “Elephant ear fig “or wild fig is one of very popular fruits found growing wild in the hills of North Eastern and North Western Himalayan region. The fruit of wild fig has also been used as medicine by the tribal people of Sikkim and other states of India. Keeping this in view, the present study was conducted at Laboratory of Department of Horticulture, Sikkim University, Sikkim to access the different nutraceuticals properties as nutritional constituent like protein, fat, fibre, carbohydrate and energy value, mineral content viz.Ca, K, Mg, Na, Zn, Co, Mo, Fe, Mn and phytochemical content such as total phenols, flavonoid, ascorbic acid, anthocyanin and total carotenoids of F. roxburghii. The results of present study revealed that fruit of F. roxburghii contains significant amount of nutritional, mineral and phytochemical properties viz. protein (3.00±0.06%), fat (0.13±0.04%), fibre (3.06±0.02%), carbohydrate (90.81±0.44 %), energy value (376.45±1.44), Ca (23.69 ± 1.7), Mg (73.09 ± 2.1), K (819.64 ± 12.54), Mo (0.58 ± 0.06), Na (6.73 ± 1.2), Zn (0.34 ± 0.10). Fe (26.55 ± 2.8), Cu (4.22 ± 0.20), Mn (7.11 ± 0.11), total phenols (4.13±0.52 mg GAE/ G), total flavonoid (3.10±0.09 mg GAE/ G), ascorbic acid (3.36±0.27 mg GAE/ G), anthocyanin (1.13±0.15 mg GAE/ G) and total carotenoids (0.68±0.10 mg GAE/ G). It may be concluded that the fruit of F. roxburghiiis rich in nutraceuticals and must be incorporated in our balanced diet.

Reduced graphene oxide (RGO)–cobalt hydroxide [Co(OH) 2 ] composite was synthesized using one-pot hydrothermal method. The frequency-dependent dielectric properties and leakage conduction mechanism were studied for the composite. Samples were made with different reaction times of 2, 4, 6 and 12 h for the same concentration of graphene oxide and cobalt nitrate at constant temperature and pH. A high dielectric constant of 7.19 × 10 6 with a capacitance of 2.45 × 10 −6 F was achieved for a reaction time of 2 h, at 100 Hz frequency and 27 °C temperature. One order decrement in the dielectric constant (10 5 ) was found with an increase in time starting from 4 to 12 h. The leakage current characteristics revealed Schottky barrier-type conduction mechanism in the composites. Thus, RGO-Co(OH) 2 composite with a high dielectric constant, microcapacitance and large leakage current could be regarded as a potential high- k candidate, which has its application as a gate dielectric material in the fabrication of metal oxide semiconductor field effect transistor.

A new α-Tetralone based chalcone compound, (2E)-2-(4-ethoxybenzylidene)-3,4-dihydro-2H-naphthalen-1-one (EBDN) has been synthesized by Claisen–Schmidt condensation reaction of α-Tetralone (1) with 4-Ethoxybenzaldehyde (2) in basic medium. Then it was allowed to grow through slow evaporation solution growth technique. The molecular structure of grown EBDN has been systematically characterized by SCXRD, FT-IR, 1H NMR and 13C NMR spectroscopic studies. The micro-hardness, thermal (TGA & DTA) and photoluminence studies of the synthesized EBDN were also examined. The EBDN was screened for its anti-inflammatory, antidiabetic and anti-oxidant activity. It has shown admirable anti-inflammatory and antidiabetic activity. Protein-Ligand interactions of EBDN with SARS-CoV-2 main protease (PDB code: 6yb7) also performed.

Currently, the use of sensors and supporting technologies has become indispensable in the assessment of tribological behavioral patterns of composites. Furthermore, the current investigation focused on the assessment of the tribological behavior of the Al&ndash, SiCp composite for high-temperature applications. Moreover, the Al&ndash, SiCp composite was fabricated by adapting the liquid metallurgy route with varying weight percentages of SiCp (x = 3, 6, and 9). Density, hardness, and high-temperature wear tests were performed to evaluate the hardness and tribological characteristics and properties of modern-day advanced composites. Moreover, the inclusion of SiCp enhanced the advanced composite materials hardness from 60 HV to 110 HV due to a high degree of refinement of the &alpha, phase. Subsequently, the fabricated samples&rsquo, wear behavior was assessed by varying the wear parameter viz. the applied load (20 N and 30 N) and sliding distance (250 m, 500 m, 750 m, and 1000 m) with the constant sliding velocity (0.45 m/s) for various temperatures (40 &deg, C, 150 &deg, C, and 250 &deg, C). Moreover, the results revealed that the enhancement in the reinforcement percentage improves the wear resistance. Consequently, the wear rate decreased at 250 &deg, C, possibly owing to the development of the oxide layers. Therefore, the occurrence of delamination and plastic deformation were evidenced in the wear-out surface, thereby depicting the prevalence of delamination and the abrasive wear-mechanism.

Developing a high specific-capacitance, quick charging and long cycle supercapacitor electrodes are essential for the future energy storage devices. In this paper, we report defect induced reduced graphene oxide (dRGO)-MnOx composites, which were prepared through redox reaction of KMnO4 and graphene oxide. The deformation/increasing defects in graphene sheets confirmed through micro-Raman studies. The dRGO-MnOx composite exhibit a high specific-capacitance, 264 Fg−1 at 0.2 Ag−1 in 1 M Na2SO4 neutral electrolyte. Most importantly, the dRGO-MnOx electrode was able to inhibit the outstanding cyclic performance of 153% capacitance retention and 100% Coulombic efficiency after 10,000 cycles at a high current density of 10 Ag−1. It also had 85% capacitance at a very short time (1/10 charging time of 0.2 Ag−1) with a charging current density at 1 Ag−1 and discharge current density of 0.2 Ag−1. The as-prepared dRGO-MnOx composites will find potential use in electrochemical energy storage applications.Developing a high specific-capacitance, quick charging and long cycle supercapacitor electrodes are essential for the future energy storage devices. In this paper, we report defect induced reduced graphene oxide (dRGO)-MnOx composites, which were prepared through redox reaction of KMnO4 and graphene oxide. The deformation/increasing defects in graphene sheets confirmed through micro-Raman studies. The dRGO-MnOx composite exhibit a high specific-capacitance, 264 Fg−1 at 0.2 Ag−1 in 1 M Na2SO4 neutral electrolyte. Most importantly, the dRGO-MnOx electrode was able to inhibit the outstanding cyclic performance of 153% capacitance retention and 100% Coulombic efficiency after 10,000 cycles at a high current density of 10 Ag−1. It also had 85% capacitance at a very short time (1/10 charging time of 0.2 Ag−1) with a charging current density at 1 Ag−1 and discharge current density of 0.2 Ag−1. The as-prepared dRGO-MnOx composites will find potential use in electrochemical energy storage applications.

Mixed-age cultures of a phosphine-resistant strain of lesser grain borer, Rhyzopertha dominica (F.) were exposed to various concentrations of phosphine and phosphine plus 10, 20 and 30% carbon dioxide combinations (CO 2 ) for different time intervals at 25 °C to evaluate the comparative efficacy of admixtures of phosphine-CO 2 . The mortality data of the mixed age cultures were recorded taking the adult count at weekly intervals for 8 weeks. Lethal concentrations were determined by probit analysis. Phosphine with carbon dioxide exerted significant synergistic effect on the mortality of mixed-age cultures at 4, 6 and 7 days of exposure, while individually phosphine or carbon dioxide did not show a raised increase in their response. The addition of 30% carbon dioxide to lower concentrations of phosphine over shorter exposures of 4 days showed better synergistic effect among the treatments. The present study revealed that CO 2 augmented the effect of phosphine thereby reducing the concentration and exposure time required to bring about significant mortality in the mixed-age cultures of R. dominica .

The tamarind pod borer, Sitophilus linearis (Herbst), causes severe damage to the seed pods of tamarind (Tamarindus indica L.) in the field and during storage. The seeds pods are either sun dried or treated with neem seed oil to get rid of the weevil infestation during storage. Herein, we study the effect of phosphine (PH3) against S. linearis and compare its response with the susceptible and resistant strain of rice weevil, Sitophilus oryzae (L.), which is a commonly stored product pest. The dose-mortality response indicates that the adults of S. linearis are relatively more susceptible to PH3 than the phosphine-susceptible strain (SO-24) of S. oryzae. At 72 h, PH3 induces 100% mortality to the adults of S. linearis at a low test concentration of 0.001 mg L−1, on the other hand for S. oryzae, 0.025 and 0.243 mg L−1 concentrations are required to induce complete mortality in the PH3-susceptible (SO-24) and resistant (SO-106) strains of S. oryzae. The results of the present study imply that S. linearis can be easily mitigated at a concentration of 0.001 mg L−1 over 72 h exposure, which is well below the recommended dosage of 2.25 mg L−1 over 168 h exposure required for managing S. oryzae infestation.

Welding is the most convenient fabrication process with tremendous development in past few decades. The noteworthy technique is Activated flux TIG welding method (also known as A-TIG welding) that was well-equipped a little while back, which enhances productivity and quality of weld joints by better depth of penetration. In this research work, the electrochemical studies are performed to investigate the corrosion resistance of excellent depth of penetration A-TIG welded 316L stainless steel (SS316L) sample at room temperature. At dilute aqueous ambience, Potentiodynamic studies reveal that the SS316L welding joints have an apathetic attitude with certain range. Electrochemical Impedance calculations illustrate the breakdown occurs due to corrosion in alkaline circumstances.

The present study investigates the effect of Ce addition on the microstructure of Mg-6Al-1Zn alloy with the use of optical microscopy (OM), X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The electrochemical corrosion behaviour of Mg-6Al-1Zn alloyed with different levels of cerium was investigated using static weight loss and polarization corrosion tests in 3.5% NaCl solution. The microstructural study reveals the grain refinement of the matrix and the stability of the phase β(Mg17Al12) were disintegrated into Al4Ce and distributed along the grain boundary. The literatures show that the intermetallic Al4Ce has a high melting point and expected to show better strength behaviour at relatively high temperatures. The electrochemical results show that cerium addition above 1.5wt.% increase the corrosion current density of the developed alloy which resulted in increasing corrosion rate. The best results of refined microstructure and corrosion resistance were obtained with 1.5wt.% cerium addition.

The reinforced Metal Matrix Composite (MMC) was broadly used in various engineering applications. The light weight and high strength metal matrix components were used in aerospace and automotive applications. The silicon carbide, boron carbide, aluminum oxide and carbon fiber were used as common reinforcement materials. The magnesium and its alloys were recently has a maximum role in MMC due to its high strength and light weight. In addition to the magnesium, the aluminium and copper was included through the reinforcement of boron carbide (B4C). It was formulated through squeeze casting technique. The copper has good electrical conductivity and it has more corrosion resistance. The magnesium metal matrix was fabricated through squeeze casting technique. The Vickers hardness was determined through the different input squeeze casting factors such as pressure, pouring temperature and die temperature. The Response Surface Methodology (RSM) optimization was used to analyze the parametric effects.

The applications of non ferrous alloys have been significantly increased due to its desirable substance properties. The material strength and hardness were depend on the nature of reinforcements were added to it. In this chapter was utilized to formulate the Copper Titanium (Cu-Ti) Metal Matrix Composite (MMC) has been reinforced with Tungsten Carbide (WC). The stir casting of material fabrication technique was considered. The tungsten carbide was the suitable reinforcement for Cu-Ti composite because of thermodynamic stable system of compound was attained. The mechanical, corrosion and wear behaviors have been discussed. The wear parameters have been optimized through Taguchi and Response Surface Methodology (RSM). The influential factor on wear rate was found and compared with the variance test.

As an exploration for probable magnetic vortex state in chromium(IV) oxide (CrO2), we performed micro-magnetic simulations on CrO2 nanodiscs. For our simulation studies, we considered CrO2 nanodiscs with 100 nm diameter and 20 nm thickness. After the ferromagnetic positive or negative saturation, when the applied magnetic field along the ±x-axis was reduced, vortex states with its magnetization winding in xy-plane nucleated in the CrO2 nanodisc at ∓ 12 mT, and annihilated at ∓ 41 mT. The magnetic vortex states were found to be stable even after reducing the applied magnetic field to 0 mT. Further, switching the magnetic vortex core polarity pointing up to down and vice versa using DC as well as AC magnetic fields has been simulated. The magnetization of the vortex core instantaneously flipped by an applied DC magnetic field of ±138 mT and within 2 ns by applied 6 GHz resonance AC magnetic field with 8 mT amplitude. Furthermore, we present a comparison about the formation, remanent state and switching of the magnetic vortex state in CrO2 nanodisc with that of the most widely studied permalloy nanodisc having same dimensions.

Pyrethrins are effective food-grade bio-pesticides obtained from the flowers of Chrysanthemum cinerariaefolium and this crop cannot be cultivated widely in India due to its specific agro-climatic requirement. Hence pyrethrins are mostly imported from Kenya. Therefore, the present study aims to develop a process for augmentation of pyrethrin contents in C. cinerariaefolium callus and establish the correlation between early knockdown effects through docking on grain storage insect. In vitro seedlings were used as explants to induce callus on MS medium with different concentrations of auxins and cytokinins. Pyrethrin extracted from the callus was estimated by RP-HPLC. In callus, total pyrethrin was found to be 17.5 µg/g, which is higher than that found in natural flowers of certain Pyrethrum cultivars. The concentrations of cinerin II, pyrethrin II and jasmoline II were quite high in callus grown on solid medium. Bio-efficacy of pyrethrum extracts of flower and callus on insect Tribolium sp., showed higher repellency and early knock-down effect when compared with pure compound pestanal. Further, the rapid knockdown effect of all pyrethrins components was established by molecular docking studies targeting NavMS Sodium Channel Pore receptor docking followed by multiple ligands simultaneous docking, performed to investigate the concurrent binding of different combinations of pyrethrin. Among the six pyrethrin components, the pyrethrin I and II were found to be a more efficient, binding more firmly to the target, exhibiting higher possibilities of insecticidal effect by an early knockdown mechanism.

Mechanochemically responsive polymers and composites can be realized through the covalent incorporation of mechanophores – chemical units that undergo a specific chemical transformation in response to applied force. The transmission of macroscale mechanical load to the mechanophores and the subsequent mechanophore population response depends heavily on the matrix architecture. For this chapter, proven mechanophore function is taken implicitly; the focus is on the material, loading mode and loading history. First, preliminaries for informed research in mechanochemically responsive polymers are presented including mechanics background, mechanophore kinetics and experimental methods. Second, existing experimental results and theories on mechanophore triggering and recovery within materials are presented. The unique phenomenology associated with elastomers, glassy polymers and composites are each discussed. Finally, the design of materials whose mechanical properties are substantively modified by the mechanochemical reaction is discussed along with future prospects.

The first full and comprehensive attempt was made to standardize the time of sampling for the leaf nutrient diagnosis for Kinnow mandarin in North West semi arid zone of India by analyzing ten essential elements collected from spring cycle leaves. The samples were collected from February to January at monthly intervals for two years and the results revealed that the 6–7 month (August–September) old spring cycle leaves collected from terminal position of non- fruiting terminal is the best suitable time for foliar nutrient analysis in Kinnow mandarin grown in the North West India. In addition, the leaf nutrient concentrations of nitrogen and calcium of this period were best correlated and leaf phosphorus (P) and potassium (K) were least correlated with fruit yield by linear correlation analysis.

Although the grain-refinement practice is well established for wrought Al alloys, in the case of foundry alloys such as near eutectic Al-Si alloys, the underlying mechanisms and the use of grain refiners need better understanding. Conventional grain refiners such as Al-5Ti-1B are not effective in grain refining the Al-Si alloys due to the poisoning effect of Si. In this work, we report the results of a newly developed grain refiner, which can effectively grain refine as well as modify eutectic and primary Si in near eutectic Al-Si alloys. Among the material choices, the grain refining response with Al-1Ti-3B master alloy is found to be superior compared to the conventional Al-5Ti-1B master alloy. It was also found that magnesium additions of 0.2 wt pct along with the Al-1Ti-3B master alloy further enhance the near eutectic Al-Si alloy's grain refining efficiency, thus leading to improved bulk mechanical properties. We have found that magnesium essentially scavenges the oxygen present on the surface of nucleant particles, improves wettability, and reduces the agglomeration tendency of boride particles, thereby enhancing grain refining efficiency. It allows the nucleant particles to act as potent and active nucleation sites even at levels as low as 0.2 pct in the Al-1Ti-3B master alloy. � 2011 The Minerals, Metals & Materials Society and ASM International.

The synthesis and characterization of several hexa-coordinated ruthenium(III) Schiff base complexes of the type [RuX(EPh3)(L)] (X = Cl or Br; E = P or As; L = dianion of the tetradentate Schiff base) are reported. IR, EPR, electronic spectra and cyclic voltammetric data of the complexes are discussed. An octahedral geometry has been tentatively proposed for all of these complexes. The new complexes have been subjected to catalytic activity in the reaction of oxidation of alcohols in the presence of N-methylmorpholine-N-oxide. Copyright © 2007 John Wiley & Sons, Ltd.

The susceptibility of the developmental stages of rust-red flour beetle, Tribolium castaneum to a range of concentrations of phosphine over varying durations from 24 to 168 h was reconnoitered in the laboratory at 25 ± 2 °C. Responses of the life stages exposed to phosphine were compared with those of un-treated controls over 24, 48, 72, 96, 120, 144 and 168 h exposures and mortality was assessed after 14 days. Among the life stages tested, pupae were more tolerant to phosphine followed by the egg and the larval instars. At 24 h, the maximum LC50 value was observed in case of egg; 1.571 mgL(-1); followed by the pupae, 6(th) instar, 4(th) instar and 2(nd) instar larvae with LC50 values of 1.184, 0.336, 0.212 and 0.081 mgL(-1) respectively. However, continued exposure of the developmental stages to phosphine, recorded maximum LC values in the pupae followed by egg and the larval instars. A linear increase in the mortality response was witnessed in all the insect stages when the exposure periods were extended from 24 to 168 h with increasing concentrations of phosphine, conversely significant increase in mortality was greatly apparent during the initial treatment periods.

Poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT–PSS) was blended with poly(vinyl alcohol) (PVA) to form 0, 10, 20, 30, 40, and 50 vol % PEDOT–PSS/PVA solutions, and their freestanding films were prepared with a simple and cost-effective solution casting technique at 27 °C in the absence of additives. Field emission scanning electron microscopy images revealed changes in the cocontinuous network to a rodlike morphology in the composite films from 10 to 50 vol % PEDOT–PSS/PVA. The alternating-current conductivity was found to obey Jonscher's power law. The obtained values of the dielectric constant at 27 °C were relatively high, and a maximum value of 6.7 × 104 at 100 Hz for 40 vol % PEDOT–PSS'/PVA was observed. The dielectric loss attained a maximum value of about 106 at 100 Hz for 40 vol % PEDOT–PSS/PVA. However, a decrease in the dielectric parameters was observed at 50 vol % PEDOT–PSS/PVA because of locally induced strain in the microstructure. The variations in polarization with respect to the applied electric field (P–E) were determined for 50, 100, and 500 Hz at 500 V for the freestanding composite films of lower concentrations up to 20 vol % PEDOT–PSS/PVA. In summary, the dielectric and P–E measurements confirmed that the electrical characteristics changed in accordance to the contribution from both resistive and capacitive sites in the PEDOT–PSS/PVA composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2017

In this work, in vitro biosynthesis of silver nanoparticles was achieved using AgNO(3) as a substrate by Penicillium fellutanum isolated from coastal mangrove sediment. The biosynthesis was faster within minutes of silver ion coming in contact with the cell filtrate. Presence of silver nanoparticles in the culture filtrate was confirmed by absorption peak at 430 nm, as well under transmission electron microscope. The biosynthesis of nanoparticles was the maximum when the culture filtrate was treated with 1.0 mM AgNO(3), maintained at 0.3% NaCl and pH 6.0, incubated at 5 degrees C for 24h. The culture filtrate, precipitated with ammonium sulphate, was proved to have a single protein band with a molecular weight of 70 kDa using polyacrylamide gel electrophoresis. The present work highlighted the possibility of using the marine fungal strain of P. fellutanum to achieve a fast rate of nanoparticles synthesis.