Removal of Toxic As (V) Ions by Adsorption onto Alginate and Carboxymethyl Cellulose Beads

The removal of arsenic ions from dilute aqueous solutions using biopolymeric beads of crosslinked sodium alginate and carboxymethyl cellulose (CMC) as the adsorbent is reported in this paper. The biopolymeric alginate and carboxymethyl cellulose beads were prepared and characterized by FTIR spectra. On the surfaces of the prepared beads were performed static and dynamic adsorption studies of arsenic ions at fixed pH and ionic strength of the aqueous metal ion solutions. The adsorption data were applied to Langmuir and Freundlich isotherm equations and various static parameters were calculated. The dynamic nature of adsorption was quantified in terms of several kinetic constants such as rate constant for adsorption (k₁) and Lagergreen rate constant (K_ad). The influence of various experimental parameters such as solid to liquid ratio, pH, temperature, presence of salts and chemical composition of biopolymeric beads were investigated on the adsorption of arsenic ions.     

Magnetic and Mössbauer properties of Fe doped VN nanoparticles

Nanoparticles of iron doped vanadium nitride are synthesized by simultaneous thermal decomposition and nitridation of [V_(1???x)Fe _x O(NH₂O)₂Gly]·H₂O in NH₃ atmosphere at 973 K for 4 h. Pure VN shows cubic NaCl structure with lattice parameter of a?=?4.126 Å. Lattice parameter increases with Fe-doping. Magnetization increases with increase of Fe amount in VN. Coercivity values are in the range 30–80 Oe, which is relatively so small, compared to pure Fe. From Mössbauer study, it is inferred that single resonance line is due to the high diamagnetic contribution and doublet peaks are due to the paramagnetic contribution, which is assigned to the presence of ζ-Fe₂N phase.     

Noise characteristics of tractors and health effect on farmers

An investigation was conducted to determine the noise propagation (under stationary condition) and noise at operator’s ear level of popular 18.7 and 26.1 kW tractors and 4.6 and 6.7 kW hand tractors during field operations with various implements. It was observed that both tractors produced the noise of 92 dB(A) L_eq in the working zone of operator. The sound pressure level (SPL) of the hand tractor was about 2 dB(A) L_eq higher than that of the tractor. The SPL during field operations at operator’s ear level increased with increase in engine speed and forward speed. Furthermore, the SPL was higher for field operations corresponding to the implement requiring higher draft. It was observed that the SPLs of the tractors and hand tractors were more than the exposure limit of noise for 8-h workday recommended by ISO and OSHA. This may cause health problems to the farmers in the long run.     

Removal of Cobalt Ions from Aqueous Solution by Adsorption onto Cross-Linked Calcium Alginate Beads

The removal of cobalt ions from dilute aqueous solutions using cross linked calcium alginate beads as the adsorbent is reported in this article. The influence of various experimental parameters such as pH, initial metal ion concentration, contact time and solid to liquid ratio were studied. The adsorption data were applied to Langmuir and Freundlich isotherm equations and various static parameters were calculated. It was observed that the uptake of cobalt ions was found to increase with time and that maximum adsorption was obtained within the first 60 minutes of the process. These results indicate that the cross linked calcium alginate beads have potential for removing cobalt ions from industrial waste water.     

Design,Synthesis, and Characterization of Quinoxaline Derivatives as a Potent Antimicrobial Agent

A series of quinoxalinone derivatives were synthesized by the reaction of o‐phenylenediamine with oxalic acid to yield 1, 4‐dihydro quinoxaline‐2, 3‐dione ( 1 ) and then treated with thionyl chloride to yield 2, 3 dichloro quinoxaline ( 2 ). This was further reacted with hydrazine hydrate to produce 2, 3‐dihydrazinyl quinoxaline ( 3 ). This was finally reacted with substituted aromatic aldehydes to produce 2,3‐bis[2‐(sustituted benzylidine) hydrazinyl] quinoxalines ( 4 ). These quinoxalinone derivatives were characterized by infrared spectroscopy and nuclear magnetic resonance spectroscopy and MASS spectral data. All the synthesized compounds were evaluated for their antimicrobial activity. The results of the antimicrobial study revealed that compounds 4c , 4d , and 4i were active and exhibited better inhibitory activities as compared to standard drug ciprofloxacin. The results were further checked with protein legend interaction by using docking studies, and all the compounds exhibited good docking scores between ?8.72 and ?11.29 kcal/mol against dihydrofolate reductase protein fragment from Staphylococcus aureus (PDB ID‐4XE6). Among all compound, 4c has shown maximum docking score and found in agreement to in vitro studies.     

PPAR gamma targeted molecular docking and synthesis of some new amide and urea substituted 1, 3, 4-thiadiazole derivative as antidiabetic compound

The PPAR-γ agonist enhances the insulin sensitivity and avoids the disorganized hyperglycemic by promoting the insulin guided cellular uptake of blood glucose. Therefore, in the present work PPAR-γ has chosen as the target for the molecular docking study to design an effective agonist of the same. By this research work an effort has been made to prepare amide and urea series of 1, 3, 4-thiadiazole derivatives as 4-substituted-N-(5-(4-(1-piperidino)1-piperidinyl)-1,3,4-(2-thiadiazolyl)benzamide (4a-f) and 1-(4-substitutedphenyl)-3-(5-(4-(1-piperidino)1-piperidinyl)-1,3,4-(2-thiadiazolyl)urea (6a-f) . Both the docking score as well as the pharmacological animal study data has been suggested that the electron donating group containing compound 4f and 6f are most potent molecules for the antidiabetic activity close to the standard drug pioglitazone. It was further observed that the unsubstituted aromatic ring containing derivatives have also considerable effect (4a and 6a) than the electron withdrawing containing derivatives. After the comparison of biological data for amide and urea series, it was concluded that the urea (6a-f) series is more effective than the amide series.     

Interaction of Folic Acid with Mn2+ Doped CdTe/ZnS Quantum Dots: In Situ Detection of Folic Acid

To utilize the nanomaterials as an effective carrier for the drug delivery applications, it is important to study the interaction between nanomaterials and drug or biomolecules. In this study GSH functionalized Mn²⁺-doped CdTe/ZnS QDs has been utilized as a model nanomaterial due to its high luminescence property. Folic acid (FA) gradually quenches the FL of GSH functionalized Mn²⁺???doped CdTe/ZnS QDs. The Stern-Volmer quenching constant (K_sv), binding constant (K_s) and effective quenching constant (Ka) for the FA-QDs system is calculated to be 1.32?×?10⁵ M^?1, 1.92?×?10⁵ and 0.27?×?10⁵ M^?1, respectively under optimized condition (Temp. 300 K, pH 8.0, incubation time 40 min.). The effects of temperature, pH, and incubation time on FA-QDs system have also been studied. Statistical analysis of the quenched FL intensity versus FA concentration revealed a linear range from 1?×?10^?7 to 5.0?×?10^?5 for FA detection. The LOD of the current nano-sensor for FA was calculated to be 0.2 μM. The effect of common interfering metal ions and other relevant biomolecules on the detection of FA (12.0 μM) have also been investigated. L-cysteine and glutathione displayed moderate effect on FA detection. Similarly, the common metal ions (Na⁺, K⁺, Ca²⁺ and Mg²⁺) produced minute interference while Zn²⁺ Cu²⁺ and Fe³⁺ exert moderate interference. Toxic metal ions (Hg²⁺ and Pb²⁺) produced severe interferences in FA detection.

Graphical abstract

GSH-Mn²⁺ CdTe/ZnS QDs based Fluorescence Nanosensor for Folic acid

     

Distorted wave eikonal approximation for elastic electron-atom scattering

By treating the static field of the atom exactly and using the eikonal wavefunction to bring in the couplings to all remaining atomic states, a simple formula for elastic scattering amplitude is derived. Its usefulness is demonstrated by applying it to electron—hydrogen scattering.     

Best proximity pair theorem in metrizable topological vector spaces

The object of this paper is to prove an existence result on best proximity pair. For this purpose, the class of factorizable multifunctions in approximately weakly compact, convex subset of metrizable topological vector space is used. As consequence, our theorem generalizes the result of Basha and Veeramani^[10]. Finally, certain known results have also been obtained as corollaries in this work.     

Strong Convergence of New Iteration Process for a Strongly Continuous Semigroup of Asymptotically Pseudocontractive Mappings

In this article, we establish strong convergence theorems for fixed points of strongly continuous semigroup of uniformly Lipschitzian asymptotically pseudocontractive mappings, in the framework of real Banach space.