The toxic action of phosphine in combination with some alkyl halide fumigants and carbon dioxide against the eggs of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae)

The toxicity of phosphine, three alkyl halide fumigants (ethylene dibromide, methyl bromide and methyl iodide), carbon dioxide, mixtures of phosphine + alkyl halide fumigants, and phosphine + carbon dioxide, to 1-, 2-, and 3-day-old eggs of Tribolium castaneum Herbst was studied. Combinations of phosphine and alkyl halide fumigants showed antagonism as evidenced by their joint action ratios at the LD₉₀ (< 1). The mortality data indicated that mixtures of phosphine and carbon dioxide were more effective than either alone. At LD₅₀, the order of toxicity of the individual fumigants for a 24 hr exposure and on a weight basis (mg fumigant/litre of air) was: phosphine > methyl iodide > ethylene dibromide > methyl bromide. A decline in susceptibility of eggs with age for methyl bromide and ethylene dibromide and a peak tolerance at 2 days for carbon dioxide were noted.     

Enhancement of electrical parameters of PANI—A conducting polymer with low concentration nanofiller for optoelectronic and electrical application

Electrical conductivity is emerging as one of the most essential material's qualities of the 21st century due to the lightning-fast advancements in the electronics sector and the continuously improving electrical goods. As conductive materials are used in the majority of the modern items we use, including power sources, energy generating systems, electrical circuits, sensors, and many others, continuing advancement in this field is very crucial. The novelty of this work lies in the dispersion of ferrite nanoparticles, which was synthesized using egg albumen to enhance the electrical behavior of PANI polymer films. In this research work, a simple casting approach was used to ex situ polymerize aniline to fabricate ultrathin and flexible CuFe₂O₄ distributed PANI films for electrical conductivity applications. The combustion approach was used to produce the copper ferrite nanoparticles, while egg albumen was not only used as the fuel but also it was used a capping agent to control the size of ferrite NPs with a size much lower than that already reported. Studies on the structural, morphological, and electrical properties of pure and various weight percent of (1 , 3 , and 5 wt%) CuFe₂O₄ loaded PANI films were performed. Comparing the different films, the 5 wt% CuFe₂O₄ dispersed PANI films exhibited remarkable and greatly improved permittivity and electrical conductivity with low dielectric loss. This indicates the 5 wt% CuFe₂O₄ dispersed PANI films have the prospective uses in high-tech industries where there is a need for flexible, thin, and lightweight high electrical conducting materials with lesser loss factor.     

Thermoplastic Polymers/Silicon Nanocomposites: Influence of Concentration on Morphological,Optical, and Electrical Properties

Silicon - The following thermoplastic polymers were used in this study at several concentration (0.50, 0.75, and 1.00%) and were deposited on porous silicon particles (PSi) to use the spin coating...     

The electrochromic and photocatalytic properties of electron beam evaporated vanadium-doped tungsten oxide thin films

The electrochromic and photocatalytic properties of vanadium-doped tungsten trioxide thin films prepared at room temperature (300 K) by the electron beam evaporation technique are reported in this paper. The vanadium to tungsten ratio (V/W) in these films are 0.003, 0.019, 0.029 and 0.047. The optical band gap of the vanadium-doped tungsten oxide (WO₃) thin film initially increases from 3.16 to 3.28 eV for V/W ratio 0.003 then decreases to 3.15 eV for V/W ratio 0.047. These vanadium-doped films switch between neutral gray and transparent states. The coloration efficiency (CE) decreases from 82 cm² C⁻¹ (pure WO₃) to 27 cm² C⁻¹ for the film containing V/W ratio 0.047. The photocatalytic activity has enhanced with vanadium doping and maximum activity of 15% (percentage change in optical density of methylene blue due to photo degradation) has been observed for the film containing V/W ratio of 0.019. The Kelvin probe measurements show that the work function of pure WO₃ films is 4.07 eV and vanadium doping initially increases the work function to 4.19 eV for V/W ratio 0.019 and then decreases it to 3.97 eV for film with V/W ratio 0.047.     

Control of internal fungi of sorghum by fumigation

Laboratory methods of fumigation of food commodities and surface sterilization of grains have been described. Out of eight fumigants tested ethylene oxide, methyl bromide, sulphur dioxide, EDB-MB mixture could give a hundred per cent control of internal fungi of sorghum. Ethylene oxide reduced the viability totally, while sulphur dioxide at 64 mg/l maintained 75 per cent viability. There was increase in the germination percentage over the control with the treatments of ethylene dibromide and phosphine.     

Chlorosulphonyl Group as a New Functionality on Fullerenes: [2+2]-Cycloaddition of Chlorosulphonylisocyanate to C60

Abstract

The chlorosulphonylisocyanate reacts smoothly with C₆₀ in xylene under thermal conditions in a [2+2]-cycloaddition fashion to yield the bisadduct as one of the products in the inseparable reaction mixture. The reaction product is analysed by FAB-MS, ¹³C NMR, FT-IR and HPLC techniques. Results show the formation of imino-lactone as one of the favourable products.     

Surface Damage of Yttria-Tetragonal Zirconia Polycrystals and Magnesia-Partially-Stabilized Zirconia in Single-Point Abrasion

Commercially available 3Y-TZP and Mg-PSZ flats were abraded by a 150° diamond cone at -196°, 25°, 200°, and 400°C. The coefficient of friction, the track width, and the morphological features of the track were recorded. Raman spectroscopy was used to record the tetragonal-to monoclinic phase transformation ( t → m ) as a function of distance away from the track. The study was undertaken to establish the influence of tangential traction on phase transformation and surface damage.     

Preparation and Characterization of Binder Less Mg/Mg Alloy Infiltrated SiC<Subscript>p</Subscript> Reinforced Composites

SiC_p-reinforced commercial pure magnesium and AZ91 alloy MMCs’ were prepared through infiltration route without the use of any special atmospheres. The preform was prepared using a mixture of reinforcement particles and the matrix metal particles. The composites were prepared with various volume percentage of the reinforcement and their properties with the variation of SiC_p were analyzed. The interfacial properties of the composites were analyzed using microstructure, microhardness, and wear studies. Calculation of thermal conditions during infiltration was done to study the effect of adding matrix metal particles on the infiltration behavior and its effect on the uniformity distribution of the reinforcements.     

Effect of Fatigue Damage Parameter on the Cumulative Life of a Turbine Rotor Under Multiaxial Loading

The effect of the fatigue damage parameter on the cumulative life of a high-speed turbine rotor has been estimated through finite element approach. Two most commonly used multiaxial fatigue damage models based on critical plane approach-Fatemi Socie (FS) model, and Kandil Brown and Miller model (KBM) have been used to estimate the fatigue life. Structural integrity test was carried out in spin test facility to validate the simulation results. KBM model for fatigue life estimation and LMP model for creep damage predicted a cumulative life within a factor of 1.5 scatter band of the experimental value. The combination of FS model for fatigue life estimation and LMP model could predict cumulative life only within a scatter band of 2. Some of the shortcomings attributed to LDS method can be obviated using a suitable fatigue damage parameter. The study provides invaluable input and confidence for the life prediction of high-speed gas turbine rotors.     

Enhanced performance of 4,4′-bipyridine-doped PVDF/KI/I<Subscript>2</Subscript> based solid state polymer electrolyte for dye-sensitized solar cell applications

Pure (PVDF/KI/I₂) and 4,4′-bipyridine-doped PVDF/KI/I₂ solid state polymer electrolytes were prepared by solution casting method using N,N-dimethylformamide (DMF) as solvent. The solid state polymer electrolytes were characterized by the powder X-ray diffraction (PXRD), Fourier transform infrared (FTIR), AC-impedance, dielectric measurements and scanning electron microscopy (SEM) analysis. The crystallinity of the solid state polymer electrolytes was analyzed by PXRD measurement. The functional groups of the solid state polymer electrolytes were confirmed by FTIR analysis. The AC-impedance analysis was carried out to calculate the ionic conductivity of the solid state polymer electrolytes. The ionic conductivity value of pure (PVDF/KI/I₂) and 4,4′-bipyridine-doped PVDF/KI/I₂ solid state polymer electrolytes are 2.00?×?10^?6 S cm^?1 and 4.60?×?10^?5 S cm^?1, respectively. The dielectric properties of solid state polymer electrolytes were calculated by using the dielectric measurements. From the SEM analysis, the surface morphology of the solid state polymer electrolytes was analyzed. The power conversion efficiencies of pure (PVDF/KI/I₂) and 4,4′-bipyridine-doped PVDF/KI/I₂ solid state polymer electrolytes are 1.8% and 4.4%, respectively. 4,4′-bipyridine-doped PVDF/KI/I₂ solid state polymer electrolyte has higher power conversion efficiency due to its increased amorphous nature and ionic mobility.