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Recently, CaO‐doped (≤4 mol.%) tetragonal zirconia (CaSZ) ceramic was recommended as a potential alternative to yttria‐stabilized ZrO2 (YSZ). Here, we investigate the limits of starting particle sizes on the stability of tetragonal (t) phase and other associated benefits on measured properties. Synthesized CaSZ powders calcined with different temperatures were used as a mono‐sized or mixed (i.e., two different calcination temperatures) batch fraction for making dense CaSZ ceramic. The mixed‐batch powders were found to be far more efficient in stabilizing the t‐phase in ceramic. Compared to YSZ, CaSZ recorded remarkable enhancement in toughness (up to 8.3 MPa m$\sqrt {\mathrm{m}} $). Contrary to YSZ, CaSZ ceramic demonstrated outstanding thermal stability. [ABSTRACT FROM AUTHOR]

Mixed‐mode chromatography open tubular column has been developed for peptide separation in electrochromatography. A column with 92 cm effective length and 50 μm internal diameter is fabricated internally with a copolymer sheet of restricted thickness. Catalyst facilitated binding of the coupling agent 3,5‐bis (trifluoromethyl) phenyl isocyanate has been carried out at the interior surface of the column. The initiator sodium diethyldithiocarbamate was bound to the coupling agent. A small amount of N‐[2‐(acryloylamino) phenyl] acrylamide was used along with methacrylic acid and styrene in the monomer mixture to induce a little polar character in the stationary phase fabricated inside the column. Twenty‐three peptides have been separated from a chemically digested protein mixture present in cytochrome C in capillary electrochromatography, in addition to the separation of six commercial peptides. We achieved an average plate count of over 1.5 million/m with the column of current study both for the digested protein components and commercial peptides using 70/30% v/v (acetonitrile/20 mM ammonium formate) at pH 6.5. In addition, the column resulted in baseline separation of all the peptides with very good resolution, enhanced peak capacity, and better retention time span. [ABSTRACT FROM AUTHOR]

• Atomic Orbital Search metaheuristic algorithm is used to extract solar parameters. • RMSE has been calculated using both frameworks used in the published literature. • Calculations have been performed for thirty published literature data. • AOS provides better performance compared to other advanced algorithms. In the available literature, there are several methods and techniques are employed to extract the unknown parameters of solar cell. The performance of the method used is validated on the basis of Root Mean Square Error (RMSE) value. This work aims to promote a decent basis for proper investigation and the implementation of an optimization algorithm to extract solar unknown parameters. In this work, the true value of RMSE is calculated for the single diode model of the RTC France solar cell using 30 different methods published in several literatures. The obtained results show that the approach of calculating RMSE is not precise in most of the published literature. The Atomic Orbital Search algorithm is proposed as a new metaheuristic optimisation method to extract the parameters of a single diode, double diode and three diode models for RTC France and PVM752 GaAs thin film solar cell. Last, the performance of the proposed algorithm is compared with other different optimisation algorithms. It is observed that the proposed algorithm gives best results with less RMSE as compared to other algorithms. This work intends to provide a solid foundation for thorough analysis and implementation of an optimization technique to extract unknown solar parameters. [ABSTRACT FROM AUTHOR]

Sintering of ceramics is known to suffer from homogeneity issues (of phase, microstructure, etc.). The present work aims to provide a simple solution for the same via positioning the sample vertically during conventional sintering. Via vertical sintering, we present two different case studies (with doped-ZrO 2 and La 2 Ce 2 O 7 systems) and illustrate two distinct benefits; e.g., restricting the formation of an otherwise deleterious monoclinic phase in zirconia bodies, and ensuring uniform in-plane texture development on both sides of the ceramic. In each case, the issues observed in the horizontally placed ceramic have been explained in connection to the heat transfer in the ceramic body. Discrepancies in heat transfer resulted in variations in grain orientation and size (mean, median, and cumulative size distribution), eventually leading to different phase developments and texture. This small adjustment (of the positioning of ceramic bodies) may be beneficial at an industrial scale; especially with samples having a large length/diameter ratio. [Display omitted] • Crucial dependence of positioning of ceramic samples during conventional sintering. • Doped-ZrO 2 and La 2 Ce 2 O 7 ceramic was chosen for the case studies. • Vertical sintering resulting in uniform texture and control phase-purity. • Horizontal sintering depicted abundant monoclinic-ZrO 2 phases. • Discrepancies noted for in-plane texture of horizontally sintered La 2 Ce 2 O 7 ceramic. [ABSTRACT FROM AUTHOR]

A molecularly imprinting polymer (MIP) was synthesized for Basic Blue 3 dye and applied to wastewater for the adsorption of a target template. The MIPs were synthesized by bulk polymerization using methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA). Basic Blue 3 dye (BB-3), 2,2′-azobisisobutyronitrile (AIBN) and methanol were used as a functional monomer, cross linker, template, initiator and porogenic solvent, respectively, while non-imprinting polymers (NIP) were synthesized by the same procedure but without template molecules. The contact time was 25 min for the adsorption of BB-3 dye from 10 mL of spiked solution using 25 mg polymer. The adsorption of dye (BB-3) on the MIP followed the pseudo-second order kinetic (k2 = 0.0079 mg·g−1·min−1), and it was according to the Langmuir isotherm, with maximum adsorption capacities of 78.13, 85.4 and 99.0 mg·g−1 of the MIP at 283 K, 298 K and 313 K, respectively and 7 mg·g−1 for the NIP. The negative values of ΔG° indicate that the removal of dye by the molecularly imprinting polymer and non-imprinting polymer is spontaneous, and the positive values of ΔH° and ΔS° indicate that the process is endothermic and occurred with the increase of randomness. The selectivity of the MIP for BB-3 dye was investigated in the presence of structurally similar as well as different dyes, but the MIP showed higher selectivity than the NIP. The imprinted polymer showed 96% rebinding capacity at 313 K towards the template, and the calculated imprinted factor and Kd value were 10.73 and 2.62, respectively. In this work, the MIP showed a greater potential of selectivity for the template from wastewater relative to the closely similar compounds. [ABSTRACT FROM AUTHOR]

• Thermophysical properties measured for textured and un-textured La 2 Ce 2 O 7 ceramics. • Texturing took place along the closed packed 〈111〉 as well as measurement direction. • Thermal conductivity (1.68 W/mK), expansion (15.2 × 10−6/ °C) noted within 600–1200 °C. • Thermal expansion and conductivity follows a texture-insensitive trend, in general. Cubic crystals are generally known to be isotropic with respect to second rank property tensor and hence expected to show no change in relation to the measurements involving such properties. In a stark contrast, fluorite (F m 3 ¯ m) cubic textured La 2 Ce 2 O 7 ceramic depicted a strong dependence with electrical resistivity in our recent study. This motivated us to examine the effect of texture on other second rank tensor properties, namely, thermal conductivity (TC) and thermal expansion coefficient (TEC). The texturing in La 2 Ce 2 O 7 ceramic took place along the closest packed 〈111〉 direction. The thermophysical properties (TC and TEC), measured for both textured and un-textured ceramics, depicted no special relevance of texture; reveling a fundamental difference between electron conduction and thermal conduction via phonons. The dependence of thermophysical properties on the cubic systems seems to extend beyond symmetry; a number of such factors are highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

The Class-II AP-endonuclease (XthA) is a mycobacterial DNA base excision repair (BER) pathway enzyme that functions in the initial steps. It acts on DNA substrates that contain abasic sites to create nicks with 3′-hydroxyl (OH) and 5′-deoxyribose phosphate (5′-dRP) moieties. The NAD+-dependent DNA ligase (LigA) is the terminal player in mycobacterial BER and seals such nicks efficiently. Here, we demonstrate that the Mtbβ-clamp-MtbXthA complex that exists in the initial steps of BER engages with MtbLigA to form a novel tri-component BER complex. Size exclusion chromatography (SEC) experiments analysis show that the three proteins interact with equimolar stoichiometry. Small angle X-ray scattering (SAXS) analysis and associated studies reveal that the apo tri-component BER-complex adopts an extended conformation where MtbXthA is sandwiched between the Mtbβ-clamp and MtbLigA. The studies support that in the apo -complex MtbXthA binds subsite-I of Mtbβ-clamp through 239 QLRFPKK 245 motif and to MtbLigA by 104 DGQPSWSGKP 113 motif simultaneously. However, the complex adopts a less-extended conformation in the presence of substrate DNA, where MtbXthA interactions switch from predominantly subsite-I to subsite-II of the Mtbβ-clamp. Overall, the novel tri-component complex prevents futile ligation activity of MtbLigA on the product of MtbXthA and ensures forward progression of the pathway and productive mycobacterial BER interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

Highly efficient adsorbent was prepared for the removal of carbofuran and imidacloprid pesticides from wastewater. The silica monolith anchored graphene oxide composite was synthesized by the modified Fischer esterification protocol. The composite showed improved adsorption capacity for the removal of pesticides from wastewater. Graphene oxide was synthesized using the modified Hummer's method, while the silica monolith was prepared via sol–gel method. The composite was characterized via X-ray diffraction, Fourier transform infra-red, Brunauer Emmett and Teller (BET/BJH) analysis, zeta potential, and FESEM imaging. Different adsorption parameters such as pH, contact time, adsorbate and adsorbent concentration, and temperature were optimized for the adsorption of pesticides. The equilibrium and kinetic models were applied to the adsorption process of the pesticides. Qe of the composite as found to be 342.46 mg g−1 for imidacloprid and 37.15 mg g−1 for carbofuran. The adsorption process followed the pseudo 2nd order kinetic model for carbofuran (R2~0.9971) and imidacloprid (R2~0.9967). The Freundlich isotherm best fitted to the adsorption data of the pesticides with R2 value of 0.9956 for carbofuran and 0.95 for imidacloprid. The resultant adsorbent/composite material came out with very good results for the removal of pesticides. [ABSTRACT FROM AUTHOR]

The ligand 2,6-bis(E)-4-methylbenzylidine)-cyclohexan-1-one sensor has been synthesized as a fluorescence-on sensor/probe for the trace level detection of chromium III ion. The synthesized ligand was characterized by FTIR, 1H-NMR spectroscopy, and fluorimetery. The sensor exhibited an ultra-selective response to chromium among the tested heavy metal ions. Different parameters were optimized like pH, effect of concentration of sensor C, metal ion and contact time. The binding stoichiometry of C:Cr3+ was calculated to be 2:1 (Job's plot) with a significantly low detection limit of 2.3 × 10− 9 M. Sensor C were practically employed for detection of chromium in spiked water samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • The simple, fast and highly sensitive method for the determination of pinoxaden is based on fluorescence measurement of the Fe(III) based coordination complex of pinoxaden in the basic medium at 337 nm. • The signaling product is kinetically stable at room temperature having maximum fluorescence intensity with 0.2 µg mL−1 of Fe(III) at pH 9. • The complex shows a linear concentration range from 1 × 10−4,-1 × 10−3 µg mL−1 with a coefficient of determination R2 = 0.9917. • Density functional theory simulations shows stronger interaction energy (-1.11 eV) of Fe(III) ion with the pinoxaden. • The proposed approach is applied to quantify pinoxaden in the formulation and real agricultural and environmental samples and shows excellent recovery. Keeping in view the toxicity of pesticides, development of analytical methods for their determination in environmental samples is the need of the day. Herein, a simple, fast and sensitive method for the determination of pinoxaden has been described. The kinetically stable, Fe(III) based complex of pinoxaden was formed at room temperature showing maximum fluorescence intensity at 337 nm with 0.2 µg mL−1 of Fe(III) at pH 9. The complex shows a linear response in the concentration range of 1 × 10−4-1 × 10−3 µg mL−1 with a coefficient of determination R2 = 0.9917, limit of detection and limit of quantification of 8.1 × 10−5 and 2.4 × 10−4 µg mL−1, respectively, and relative standard deviation and maximum matrix effect of 0.021% and 2.13%. Density functional theory simulations were used to understand the nature of Fe(III) based complex of pinoxaden. The larger negative interaction energy of −1.11 eV evince that the Fe(III) strongly coordinated with the N-atom shared by oxadiazopine ring and the pyrazole ring and the O atom of –C O group of side chain, which are consistent with the experimental results. Interference study shows that among the metal ions studied, only Cu(II), Co(II) and Pb(II) show reasonable interference effect. The proposed approach was applied to quantify pinoxaden in the formulation and real agricultural and environmental samples. The results indicate excellent recovery in the range of 89.44 ± 1.38–97.51 ± 2.62 % for wheat, barley, water and soil samples. In soil samples no residue was quantified while in the wheat and barley samples the residue found was below the maximum residue limit. Under optimized experimental conditions, the proposed method was found to be simple, fast, reasonably interference free and has trace level sensitivity. The method was found to be comparable and even superior to some literature methods for determination of pinoxaden in complex matrices. [ABSTRACT FROM AUTHOR]