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In this study, p-morpholinomethylcalix[4]arene (p-MC4) was synthesized using Mannich reaction and utilized for the fabrication of polyacrylonitrile nanofibers impregnated with p-morpholinomethylcalix[4]arene (PAN/p-MC4) using electrospinning. The nanofibers were prepared by blending 12% solution of PAN with 20% solution of p-MC4. The PAN/p-MC4 NFs were thoroughly evaluated for their removal efficiency of Cu2+ from the aqueous media. The selectivity of PAN/-p-MC4 nanofibers was also examined by adsorbing a set of metal ions with same charge and similar ionic radius. The results of distribution ratio showed that PAN/p-MC4 nanofibers have superior selectivity for Cu2+ as compared to other heavy metal ions. The relative selectivity coefficients of PAN/p-MC4 nanofibers were found to be 25.2, 14.1, 8.9, and 4.03 for Cu2+/Ni2+, Cu2+/Co2+, Cu2+/Cd2+ and Cu2+/Pb2+, respectively. This indicates that PAN/p-MC4 nanofibers have a higher selectivity for Cu2+ ions. Numerous parameters such as pH, time, adsorbent dosage and analyte concentration were optimized to evaluate the maximum adsorption capacity of nanofibers for Cu2+. Adsorption isotherm models showed that the adsorption is promising and follows Langmuir adsorption isotherm. Whereas, PAN/p-MC4 nanofibers followed pseudo- second order kinetics during adsorption experiments. The PAN/p-MC4 nanofibers showed excellent adsorption capacity (qo) of 65.35 mg/g for Cu2+ at pH 5 in 60 min under shaking speed of 120 rpm. Moreover, PAN/p-MC4 nanofibers had been used to remove Cu2+ from real surface water samples. According to the results, PAN/p-MC4 nanofibers are more effective adsorbent for removing Cu2+ from contaminated water. [ABSTRACT FROM AUTHOR]

This study deals with the field application of lure traps for trapping of the adult red palm weevil (Rhynchophorus ferrugineus) at the date palm orchard of Sindh, Pakistan. The pheromone traps, were installed at the date palm orchard under the field conditions such as aggregation pheromone dosage, food material (molasses), ester (isoamyl acetate) and trap density. During the field trials, it was observed that the 3 mg/trap dose of aggregation pheromone along with the 500 g of molasses and 4 mg/trap of ester trapped maximum female adult insects. The 10 traps/ha was the optimized trap density. Moreover, the higher number of insects were trapped in March and the minimum catches were observed in the month of November, December, January and February. The total male and female adult weevils captured were (N=18 females 60% and N=12 males 40%) and the sex ratio was 2:3 male and female, respectively. [ABSTRACT FROM AUTHOR]

The current work explores the antioxidant and antimicrobial activity of a newly synthesized calix[4] arene acetanilide derivative (3), which was synthesized through Mannich reaction by the treatment of calix[4] arene with acetanilide, formaldehyde and acetic acid in tetrahydrofuran, The antioxidant activity was determined by using DPPH method. Results show that the new synthesized compound 3 has good antioxidant activity. The antimicrobial activity of 3 was staunched against different types of microorganisms, i.e. gram-negative and gram-positive bacterial strains (Escherichia Coli ATCC 8739 and Staphylococcus Aureus ATCC 10231) along with a fungus (Aspergillus Niger ATCC 16405). A suitable agar medium (Mueller Hinton agar) was applied for the growth of microorganisms. Kirby-Bauer well agar diffusion method was used to check the antimicrobial activity. The bacterial strains zone has been observed in between 250–4000 µg/ml. It is noticed that compound 3 has very good effect against fungus A niger as compared to bacterial strains. Its minimum inhibitory concentration (MIC) against A. niger, S. aureus and E. coli is found to be 250, 500 and 1000 µg/mL, respectively. Consequently, the study has been compared with the reported calix[4] arene derivatives and it has been revealed that the compound 3 is a good antimicrobial agent. Hence, it could be inferred that compound 3 is considerably effective against selected microorganisms and may be used as a medicine in near future and beneficial for the human. [ABSTRACT FROM AUTHOR]

This study describes the removal of methyl orange (MO) and methyl red (MR) dyes from water samples using morpholinomethylcalix[4]arene immobilised silica (MIS) resin. The silica surface has been modified by p-morpholinomethylcalix[4]arene moiety and was characterised by FT-IR spectroscopy and SEM techniques. The adsorption capacity of MIS-resin was checked through batch adsorption experiments under the optimised conditions of pH, MIS-resin dose, time, and temperature. Results show that adsorption of MO and MR dyes are highly affected by the change in pH; thus, the higher adsorption percentages were achieved at pH 5.3 and 6.6 respectively. The adsorbent dosage has been optimised and it was noticed that the maximum adsorption was achieved by using 40 mg.L−1 of MIS-resin dose. The adsorption rate of dyes was investigated by applying the pseudo-first and second-order kinetic models and it has been observed that the experimental data shows a better correlation coefficient with the pseudo-second-order kinetic model. The feasibility of adsorption was analysed by thermodynamic parameters such as ∆H°, ∆G°, and ∆S° values indicate that the adsorption of dyes is exothermic and spontaneous. The equilibrium data have been validated using Langmuir and Freundlich models and the Langmuir model has a good correlation coefficient (R2 0.99). The MIS-resin was applied onto industrial effluents and it has been observed that the prepared resin is a very efficient adsorbent for the treatment of dyes contaminated wastewater. The adsorption of MO and MR dyes onto MIS-resin was well defined by computational chemical modelling at the B3LYP/LANL2DZ/6-311++G (d,p) level using G09W software. [ABSTRACT FROM AUTHOR]

Calixarenes are known as fascinated macromolecules due to their flexible structure that can be cast into different fields of application. These macromolecules have been used as quick and highly selective functional material for the extraction and separation of metal ions. This study explores metal ion removal efficiency of new calixarene coated silica resin from aqueous environment through solid phase extraction. The calixarene-coated silica resin (CCS resin) was synthesized and characterized by FTIR, SEM, XRD, EDS and BET. Static and dynamic adsorption experiments were followed to check the removal efficiency of CCS resin. Adsorption experiment shows that, CCS resin has strong potential for the removal of divalent and trivalent metal ions as compare to monovalent metal ions. Adsorption data have been evaluated by applying Langmuir, Freundlich, D-R models and Thomas dynamic adsorption models. The adsorption isotherm of the CCS resin agreed well with the Langmuir adsorption equation with regression coefficient of 0.99 and good monolayer adsorption capacities such as 3.22, 2.95, 3.04, 3.11, 2.81 and 2.82 (mol.g−1) for Hg2+ Pb2+ La3+ Cr3+ Al3+ and Fe3+ respectively. The D-R isotherm model suggests that the adsorption process follow ion exchange mechanism with mean sorption energy falls in the range of 9.0–16 KJ.mol−1. Moreover, the exhaustion capacity of column was calculated by using the Thomas model, which shows very small qo value with good fit to data (R2 =0.99). The thermodynamic and kinetic studies have also been performed, which reveals that the reaction is spontaneous and exothermic in nature and follows pseudo second-order kinetics. [ABSTRACT FROM AUTHOR]

p-Aminophenol is an important organic molecule which is widely used in pharmaceutical as well as in dye industries for the synthesis of various drugs and corrosion resistant paints respectively. In order to synthesize this important organic molecule, CuO nanoparticles were functionalized with diamide derivative of calix[4] arene (3). The functionalized nanoparticles (4) were characterized with different analytical techniques such as FT-IR, XRD, SEM and EDX. The synthesized catalyst (4) was used to convert p-nitrophenol,in presence of sodium borohydride, into p-aminophenol which is an industrially important organic molecule. This reaction was monitored by Ultraviolet visible (UV-Vis) spectroscopy. The catalytic conversion took 35-40 seconds. The reaction followed pseudo first order kinetics and rate constant was determined as 1.386 min−1. N [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the phenolic acid profile and antioxidant activity of leaves, stem and flowers of Tamarix dioica. Nine compounds were identified by high performance liquid chromatography (HPLC). Overall results showed that the high content of gallic acid was detected in leaves and flowers and caffeic acid in stem. Antioxidant activity was evaluated using DPPH assay. A high antioxidant activity was observed, which is associated with very high phenolic content, indicating the potential benefit of using this species as a source of biochemical compounds. [ABSTRACT FROM AUTHOR]