Ultrasound-aided rapid and enhanced adsorption of anionic dyes from binary dye matrix onto novel hematite/polyaniline nanocomposite: Response surface methodology optimization

In recent times, polyaniline (PANI), a conducting polymer, has been studied widely for environmental remediation application due to its controllable electric conductivity with high surface area, which makes it a suitable adsorbent material. But lower mechanical stability of PANI is considered to be a serious drawback for its large-scale industrial application. To improve the mechanical strength of PANI, in this study, hematite nanoparticles were impregnated onto PANI by oxidative polymerization method in order to fabricate a novel organometallic nanocomposite (hematite-PANI-NC). The hematite-PANI-NC was used as adsorbent for removal of methyl orange (MO) and eosin yellow (EY) dye from binary dye matrix under ultrasonic-assisted adsorption. Excellent MO and EY dye removal (more than 98%) was observed from binary matrix at a wide solution pH from 2.0 to 6.0, and under ultrasound wave the adsorption equilibrium was achieved within 15 min only. Both MO and EY dyes adsorption experimental data strictly followed Langmuir isotherm, and maximum monolayer adsorption capacity of 126.58 mg/g and 112.36 mg/g was observed for MO and EY dye, respectively. The uptake mechanism of MO and EY dyes onto hematite-PANI-NC is governed by electrostatic interaction, π-π bonding and hydrogen bonding between dye molecules and nanocomposite. Response surface methodology analysis reveals maximum MO and EY removal of 98.43% and 99.35% at optimum experimental conditions. This study implies that the hybrid organometallic material hematite-PANI-NC has high potential for quick and enhanced sono-assisted uptake of anionic dyes from water near neutral solution pH.     

Fluctuation study of pionisation in ultrarelativistic nucleus-nucleus interaction

The scaled factorial moments and the multifractal moments have been investigated in different??-intervals to study the dynamical fluctuation of pions produced in 200 AGeV³²S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process.     

Synthesis and characterization of various phases of cobalt oxide nanoparticles using inorganic precursor

Controllable and uniform doping of nanowires (NWs) is the ultimate challenge prior to their effective application. Si NWs amorphize and bend toward the impinging ions under ion irradiation as a result of viscous flow. We demonstrate that thermal annealing induces a full recovery of the crystalline phase corresponding to the unbending of the NWs. The competition between Solid Phase Epitaxy and Random Nucleation and Growth at the nanoscale is the key parameter controlling the recovery.     

Synthesis of 1-p-Methoxyphenyl and 1-p-Methoxyphenyl-4-methylbicyclo-[2.2.1]heptan-7-one. The Oxidation of 7-Hydroxy-1-p-methoxyphenyl-4-methylbicyclo[2.2.1]heptan-7-carboxylic Acid with Lead Tetraacetate

A simple synthetic route to 1-p-methoxyphenyl and 1-p-methoxyphenyl-4-methylbicyclo [2.2.1]heptan-7-one 6b,a has been developed through benzilic acid rearrangement of the bicyclo[2.2.1]octandiones 2b,a. The oxidation of 7-hydroxy-1-p-methoxyphenyl-4-methylbicyclo[2.2.1]heptan-7-carboxylic acid 3a with lead tetraacetate gives the carbolactone 7a which is also formed by the reaction of the ketone 6a with m-chloroperbenzoic acid.     

Cu(OTf)2-promoted efficient synthetic route towards glycospiro-pyrrolo[2,1-a]isoquinolines

A simple, convenient and efficient protocol for the construction of an array of glycospiro-pyrroloisoquinolines using isoquinolinium ylide and a carbohydrate-derived exocyclic olefin in the presence of Cu(OTf)₂–Et₃N catalytic system is described. Isoquinoline and alkylbromoacetates/2-bromoacetophenones were employed to generate the azomethine ylides in the presence of Et₃N in refluxing toluene and subsequent exposure to the olefin led to the desired isoquinoline derivatives.     

Determination of calcium and iron in silicon and uranium silicide using ion chromatography

Two separate ion chromatography methods were developed for the determination of calcium and iron in silicon and uranium silicide. A cation exchange separation with conductivity detection was developed for Ca. A reversed phase column modified with 50 mM camphor-10-sulphonic acid was used for separating Fe. Iron was detected photometrically. Linear calibrations for Ca (0.1–10 ppm) and Fe (0.5–25 ppm) were performed. Limits of detections for Ca and Fe are 0.03 and 0.2 ppm, respectively. The precision of the methods are better than 2 % for Ca at 0.2 ppm and Fe at 2 ppm.     

Numerical Investigation of Graphene as a Back Surface Field Layer on the Performance of Cadmium Telluride Solar Cell

This paper numerically explores the possibility of ultrathin layering and high efficiency of graphene as a back surface field (BSF) based on a CdTe solar cell by Personal computer one-dimensional (PC1D) simulation. CdTe solar cells have been characterized and studied by varying the carrier lifetime, doping concentration, thickness, and bandgap of the graphene layer. With simulation results, the highest short-circuit current (I_sc = 2.09 A), power conversion efficiency (η = 15%), and quantum efficiency (QE~85%) were achieved at a carrier lifetime of 1 × 10³ μs and a doping concentration of 1 × 10¹⁷ cm⁻³ of graphene as a BSF layer-based CdTe solar cell. The thickness of the graphene BSF layer (1 μm) was proven the ultrathin, optimal, and obtainable for the fabrication of high-performance CdTe solar cells, confirming the suitability of graphene material as a BSF. This simulation confirmed that a CdTe solar cell with the proposed graphene as the BSF layer might be highly efficient with optimized parameters for fabrication.     

DIC Challenge 2.0: Developing Images and Guidelines for Evaluating Accuracy and Resolution of 2D Analyses

Experimental Mechanics - The DIC Challenge 2.0 follows on from the work accomplished in the first Digital Image Correlation (DIC) Challenge Reu et al. (Experimental Mechanics 58(7):1067, 1). The...     

Evaluation of elastic, elastic-plastic properties of thin Pt wire by?mechanical bending test

A testing methodology to determine the elastic-plastic properties of thin metallic wires is reported. A small-scaled bending test of Pt thin wire and the corresponding finite element analysis are performed. By fitting the load-displacement relationship obtained by finite element analysis to the experimental one, the elastic, elastic-plastic properties of Pt wire are successfully determined.     

Temporal contrast improvement in chirped pulse amplification systems by a four-grating compressor and by spectral modifications

The quest for higher peak focused intensities and better temporal contrast drives one to improve the design of all possible stages of the chirped pulse amplification (CPA) system. In this paper, we have analyzed the role of dispersion and spectral profile on the temporal shape and contrast ratio of the output pulse of a CPA system. The simulations indicate that an initial sech² or a Gaussian pulse in the CPA system is best for a good contrast ratio. Incorporating a four-grating based pulse compressor in the CPA system improves the contrast as well as provides the flexibility to compensate the dispersion upto the fourth order. The simulations also detail the effect of spectral profile tailoring on the contrast ratio and peak power.