Modulating Cation Migration and Deposition with Xylitol Additive and Oriented Reconstruction of Hydrogen Bonds for Stable Zinc Anodes

Highly reversible plating/stripping in aqueous electrolytes is one of the critical processes determining the performance of Zn-ion batteries, but it is severely impeded by the parasitic side reaction and dendrite growth. Herein, a novel electrolyte engineering strategy is first proposed based on the usage of 100 mM xylitol additive, which inhibits hydrogen evolution reaction and accelerates cations migration by expelling active H₂O molecules and weakening electrostatic interaction through oriented reconstruction of hydrogen bonds. Concomitantly, xylitol molecules are preferentially adsorbed by Zn surface, which provides a shielding buffer layer to retard the sedimentation and suppress the planar diffusion of Zn²⁺ ions. Zn²⁺ transference number and cycling lifespan of Zn ∥ Zn cells have been significantly elevated, overwhelmingly larger than bare ZnSO₄. The cell coupled with a NaV₃O₈ cathode still behaves much better than the additive-free device in terms of capacity retention.     

Mixed convection flow of hybrid nanoparticle along a Riga surface with Thomson and Troian slip condition

Journal of Thermal Analysis and Calorimetry - The target of current research is to discuss the induced magnetic field stagnation point flow of carbon nanoliquids influenced by Riga surface with...     

Thin layer coulometric determination of nitrate in fresh waters

A nitrate ion-selective electrode (ISE) employing a permeable tubular membrane impregnated with a conventional ISE cocktail has been used successfully in the coulometric analysis of nitrate in fresh waters. The liquid ISE membrane comprising a nitrate ionophore [tridodecylmethylammonium nitrate (TDMAN)], lipophilic electrolyte [tetradodecyl-ammoniumtetrakis(4-chlorophenyl)borate (ETH 500)] and plasticizer [bis(3-ethyl-hexyl)sebacate (DOS)] was supported on a porous polypropylene tube. Coulometric analysis with the tubular membrane ISE showed that nitrate could be detected in the range 10–100 μM with a precision of 2.3% relative standard deviation (RSD), limit of detection of 1.1 μM and relative accuracy of 4.4% compared to a certified reference material (CRM) Lake sample.     

Convective heat transfer and MHD effects on Casson nanofluid flow over a shrinking sheet

Current study examines the magnetohydrodynamic (MHD) boundary layer flow of a Casson nanofluid over an exponentially permeable shrinking sheet with convective boundary condition. Moreover, we have considered the suction/injection effects on the wall. By applying the appropriate transformations, system of non-linear partial differential equation along with the boundary conditions are transformed to couple non-linear ordinary differential equations. The resulting systems of non-linear ordinary differential equations are solved numerically using Runge-Kutta method. Numerical results for velocity, temperature and nanoparticle volume concentration are presented through graphs for various values of dimensionless parameters. Effects of parameters for heat transfer at wall and nanoparticle volume concentration are also presented through graphs and tables. At the end, fluid flow behavior is examined through stream lines. Concluding remarks are provided for the whole analysis.     

Effect of Non-Enzymatic Glycation on Cystatin: A Spectroscopic Study

The study shows the effect of nonenzymatic glycation on conformation and inhibitory activity of chick pea cystatin (CPC). CPC was incubated with different reducing sugars, pentose (D-Ribose), hexoses (D-Glucose, D-Fructose) at 37 °C for 5 weeks. To evaluate the modification of CPC by these different sugars during the glycation process the extent of the Maillard reaction, conformational, structural and functional changes were investigated. The behaviour of glycated CPC was monitored by the techniques of UV and fluorescence spectroscopies. Specific fluorescence was employed to characterise the glycation and AGEs. The anti-papain activity of glycated CPC was found to be significantly lower as compared to its non-glycated form. Glycation with ribose led to maximum loss in inhibitory activity. It was found that the incubation of CPC with all the mentioned sugars led to a parallel increase in tryptophan fluorescence as well as in Maillard and other AGEs specific fluorescence values and hyperchromicity in the UV-region. Among the sugars studied comparatively ribose was found to be the most active in inducing structural and conformational alterations in the protein suggesting its high reactivity with protein amino groups.     

Fabrication of Redox‐Mediator Supported Potentiometric Nitrate Biosensor with Nitrate Reductase

Fabrication of a more superior nitrate potentiometric biosensor than previously achieved with NaR and NADH has been accomplished by co‐entrapment of redox mediators and NaR into polypyrrole (PPy) film during galvanostatic polymerization of pyrrole. The replacement of NADH with redox mediators such as thionin acetate (ThAc), safranin (Saf), and azure A (AzA) gave more sensitive potentiometric responses, better minimum detectable concentration, linear concentration range and response time for nitrate than possible with NADH. The co‐entrapment of ThAc, Saf, AzA and methyl viologen (MV) with NaR into PPy films also improved the Nernstian behavior of the electrode process beyond the capability of the PPy‐NaR‐NADH biosensor. Substantial reduction in volume and quantity of cofactor/mediator and, hence cost, was achieved by the replacement of NADH with a redox mediator. Only 50 μM of AzA was required to form a PPy‐NaR‐AzA biosensor which gave the most sensitive potentiometric response for nitrate, achieving a minimum detectable concentration of 10 μM, a linear concentration range of 50–5000 μM and a response time of 2–4 s.     

Study the effect of metal ion on wool fabric dyeing with tea as natural dye

Aqueous extract of natural dye, tea was dyed on the wool fabric with dark brown for 2% and 5% shade. The tea containing tannins as the main colorant species to produce different shade with different mordant salts. The mordant salts Alum, CuSO₄, FeSO₄, ZnSO₄, Na₂SO₄, and MgSO₄ were used to dye fabric using three different dyeing methods: pre-mordanting, meta-mordanting and post-mordanting. The color of the fabric was investigated on Data Color matching system in terms of K/S and CIE Lab-color difference values. The post-mordanting method gave the great depth of shade of natural dye tea with 2% and 5% shade, it also give good light fastness and wash fastness properties. Copper was found as a good mordant to achieve the best results with transition metal ions effect. Deep shades (K/S = 17.50) were obtained for original sample of 5% with color difference ΔE value is 0.17, as compare to 2% original sample of tea of light brown shades (K/S = 10.50) with color difference ΔE value is 0.50 under maintained temperature at 85 °C for 35 min of dyeing.     

1‐Butyl‐3‐methyl Imidazolium Acetate Catalyzed Synthesis of N‐substituted‐5‐arylidene‐rhodanines

A direct method for the synthesis of N‐substituted‐5‐arylidene‐rhodanines has been reported in high yield via [bmim]OAc‐catalyzed one‐pot four‐component domino Knoevenagel condensation of primary amine, carbon disulfide, ethyl chloroacetate, and aromatic aldehyde under neat condition. The catalytic role of [bmim]OAc is due to the acidic nature of C‐2 hydrogen of bmim cation and the basic nature of acetate anion in the noncovalent interactions. The synthetic methodology is simple and offers a wide scope for the synthesis of N‐substituted‐5‐arylidene‐rhodanines.     

Synthesis,in vitro lipoxygenase inhibition,docking study and thermal stability analyses of novel indole derivatives

A series of indole derivatives has been synthesized and biologically evaluated to identify potent new lipoxygenase (LOX) inhibitors. All selected indole derivatives were screened for their LOX inhibition studies. Most of compounds showed good in vitro LOX inhibition properties exhibiting IC₅₀ values in the range of 53.61 ± 0.14 to 198.61 ± 0.11 μM (mean ± SEM), as compared to the standard inhibitor baicalein with IC₅₀ value 22.4 ± 1.3 μM. Structure activity relationship has been discussed and docking stimulation of most active compound 4f has also performed. Thermal stability and melting point of indole derivatives have been performed by thermal gravimetric analysis and differential scanning calorimetry analysis under nitrogen atmosphere at heating rate of 20 °C min^?1. Compound 4f bearing bis-phenyl moiety has been found to be the most potent (IC₅₀ 53.61 ± 0.14 μM) and thermally most stable among the tested compounds. Imine (C=N) was found to be the key moiety for increasing the thermal stabilities of indole derivatives. FT-IR, NMR and elemental analysis techniques were performed for structural characterization.     

Vanadium(III) Complexes of Oxygen Donor Ligands; Their Synthesis,Spectral Characterization and Antimicrobial Studies

A new series of vanadium(III) complexes with oxygen donor ligands have been synthesized and characterized on the basis of elemental analysis, conductance, infra‐red spectroscopy, electronic spectral data and mass spectrometry. Thermal stabilities of the complexes and their kinetics were studied through thermogravimetric analysis. Estimation of vanadium in the complexes is carried out by ICP‐AES. Biological activities of the complexes 2 – 5 , 7 and 8 have also been tested against various bacteria and fungi.