The present research focuses on removal efficiency of superparamagnetic nano iron oxide loaded poly (styrene-co-acrylic acid) hydrogel for Zn2+ ions from aqueous solution by batch adsorption technique. The influence of pH, contact time, adsorbent dose, temperature, and metal ion concentration on the sensitivity of the removal process was inspected. Out of various kinetic models proposed, the pseudo second order seems to fit in the experimental data in the best way. Different thermodynamic parameters ΔG0, ΔH0, and ΔS0 have also been evaluated. The maximum percentage removal of Zn2+ ions (95%) was obtained at pH 7 in 120 min at room temperature (25°C).
The voltammetric oxidation of an anticancer drug, 5-fluorouracil, was investigated at a multiwalled carbon nanotubes-paraffin oil paste electrode using cyclic and differential-pulse voltammetry. The oxidation process was irreversible over the pH range studied and exhibited a diffusion-controlled behavior. In the range of 0.1 × 10−6 to 5.0 × 10−6 M, the current measured by differential-pulse voltammetry presents a good linear property as a function of the concentration of 5-flurouracil with a detection limit of 3.94 × 10−8 M with good selectivity and sensitivity. The proposed method was successfully applied to 5-flurouracil determination in pharmaceutical and urine samples.
The major aim of this study was to design chitosan/alginate nanoparticles as swelling controlled drug release system for anticancer drugs. The prepared nanoparticles were characterized by FTIR and transmission electron microscopy analysis and their biocompatibility and in vitro cytotoxicity were evaluated. The nanoparticles were loaded with widely used anticancer drug, cisplatin, and controlled release of drug was investigated to observe the effects of various parameters such as percent loading of the drug, pH, temperature, and nature of release media on the release profiles. The release of cisplatin was also studied in various simulated biological fluids.
A series of polythiophene (PTP) nanocomposites with nanodimensional SnO2 were fabricated by in situ oxidative polymerization method, using FeCl3 as oxidant. These nanocomposites were characterized by FT-IR, UV-vis, XRD, TGA, SEM, and TEM techniques. The results proved the polymerization of thiophene and the strong interaction between PTP and SnO2 nanoparticles. It was found that the PTP/SnO2 nanocomposites absorbed much more visible light and red-shift took place in UV-vis spectra. TEM photographs showed that SnO2 particles have been encapsulated in PTP successfully. TGA data indicated that the PTP/SnO2 nanocomposites have higher thermal stability than that of PTP and decompose at higher temperatures.
Interaction of metal NPs with different number of ILs was studied. Basically, different energies for the interaction of various metal NP with the different number of tetrazole based ionic liquid were calculated. Herein, energies in terms of moldoc and rerank score have been calculated. How metal NPs interacts with ionic liquid in different ratio? Ionic liquid interaction energy increases on increasing the number of ionic liquids both in case of moldoc score and rerank score. Only exception has been seen when two molecules of ionic liquids interact with metal NPs showed the maximum stability. As far as metal NPs-IL interaction energy is concerned it again follows the same trend, it increases but again decreases in case of two ionic liquids. Steric interaction energy is also following the same trend. This energy is pairwise energy. Further, the deciding factor for the stability is the total energy and it increases with increase in number of IL and therefore, when the interaction of metal NPs was car...
A new zinc(II) coordination polymer, namely [Zn(bipy)2(H2O)4]n·n(dsba) (1), has been synthesized by the mixed 4,4′-biphenyldisulfonic acid (H2dsba) and 4,4′-bipyridine (bipy) ligands with Zinc(II) salt under the common solution evaporation method. The results of the X-ray crystal diffraction analysis show that complex 1 belongs to the monoclinic system with P21/c space group. The unit cell constants of complex 1 are a = 9.2579 Å, b = 12.2016 Å, c = 14.447 Å, α = γ = 90˚, β = 93.476˚. Complex 1 exhibits a three-dimensional supramolecular network based on the discrete structure by utilizing various H-bonded interactions. In addition, the properties of complex 1, such as the elemental analysis, FT-IR spectroscopy, X-ray powder diffraction, and fluorescence spectroscopy were also characterized and are discussed in detailed.
A new metal-organic coordination polymer [Zn(bm)(AcO)](n) (1), where Hbm is 1H-benzoimidazole), has been prepared and structurally characterized by IR, elemental analysis and single-crystal X-ray diffraction. Single-crystal X-ray analysis shows that it crystallizes in the monoclinic space group of P2(1)/c with a = 10.8231(5) angstrom, b = 9.8329(4) angstrom, c = 8.8665(4) angstrom, beta = 99.298(4)degrees, V = 931.20(7) angstrom(3), and Z = 4. The bm ligand bridges two adjacent Zn(II) with its two nitrogen atoms to form a one-dimensional chain, which further constructed 2D network through a bridge bidentate AcO ligand. Furthermore, luminescent property of 1 was investigated.
In this study, the authors report the synthesis and characterization of new poly(hydroxyethyl methacrylate) palladium(II) (p (HEMA)-Pd(II)) and poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester) palladium(II), p(HEMA-MAH)Pd(II) microsphere catalysts, and their catalysis in Suzuki-Miyaura coupling reactions of aryl bromides with phenylboronic acid in water. The microsphere catalysts were characterized by SEM, ICP-MS, FTIR, and diffuse-reflactance UV-visible spectroscopy. The p(HEMA)-Pd(II) and p(HEMA-MAH)-Pd(II) microsphere catalysts were active catalysts in Suzuki-Miyaura coupling reactions of arylbromides with phenylboronic acid affording biphenyls in high yield. Recycling experiments showed that the p(HEMA)-Pd(II) and p(HEMA-MAH)-Pd(II) microsphere catalysts could be used seven or ten times with essentially no loss in activity in the Suzuki-Miyaura coupling reactions.
Biological activity study on Cu(II) and Zn(II) complexes is a challenging issue because of the activity of ligands could be modulated by complexation. A new dinuclear copper(II) complex, [Cu-2(L-1)(2)]2CH(3)OH (1), and a new mononuclear zinc(II) complex, [ZnL2(CH3OH)] (2), where L-1 is the dianionic form of the bis-Schiff base N,N-bis(2-hydroxy-5-methoxybenzylidene)-1,2-ethanediamine (H2L1), and L-2 is the dianionic form of N,N-bis(5-fluoro-2-hydroxybenzylidene)-1,2-ethanediamine (H2L2), have been synthesized and characterized by single-crystal X-ray diffraction. X-ray analysis indicates that the metal atoms in the complexes are in square pyramidal coordination. Antibacterial activity of the complexes against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Candida albicans strains was studied and compared with that of the free Schiff bases.
AbstractAdsorption of malachite green (MG) onto silver nanoparticles loaded on activated carbon (Ag-NP-AC) was investigated. Useful information about this material was obtained by different techniques such as Brunauer Emmett and teller (BET), filed emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and Transmission electron microscopy. This reasonable low-cost, simple preparation and eco-friendly adsorbent is superior and alternative material to the current expensive substance for treatment of high amount of waste water. The influence of adsorbent dosage, initial dye concentration, and pH and contact time was examined to achieve and ascertain the optimal experimental conditions. The optimum dosage, pH and contact time for Ag-NP-AC were obtained to be 0.020 g, pH 5.00 and 25.0 min, respectively. The adsorption of malachite green obey the pseudo-second-order and intra-particle diffusion rate equation with 99.7% removal percentage at adsorbent dose of 0.025 g for 5–50 mg/L initial concen...
Two new complexes, [Co(aci)2(H2O)2]·2H2O (1) and [Zn(aci)2(H2O)2]·2H2O (2) (aciH = 4-oxo-5-methylpyrazine-2-carboxylic acid) were obtained by the reaction of corresponding metal salts and aciH, and characterized by elemental analysis, FT-IR spectroscopy, single-crystal X-Ray diffraction, and magnetic susceptibility measurement. X-Ray analysis demonstrates that two compounds both crystallize in triclinic system, space group P-1, and contain a mononuclear complex and two lattice water molecules. The two discrete complexes are further linked into three-dimensional hydrogen-bond networks via rich hydrogen bonding interactions.
Structural and electrical properties of the nanocrystalline cadmium sulfide (CdS) powder were effectively synthesized and annealed at 573 K, 673 K and 773 K. Cadmium sulfate and sodium sulfide was used as a starting precursor for the preparation of CdS nanoparticles. The XRD results confirmed that major phase of hexagonal structure-CdS along with partial oxidation of CdO and CdSO3 nanoparticles. It reveals that the average crystallite size varies from 25 to 41 nm as annealing temperature increases. The phase and functional group composition was studied through FTIR. The average particle size distribution of CdS nanoparticles is 39, 47, and 49 nm for 573, 673, and 773 K, respectively. The surface morphology of CdS particles revealed the compact crystalline structure. Electrochemical impedance spectroscopy studies showed that the charge transfer resistance is lowered as annealing temperature is increased.
By virtue of a solvothermal reaction, a new cadmium-bipyridinium derivative (N,N′-dimethyl-4,4′-bipyridinium)3(CdCl3-HCl-CdCl3)(CdBr4)2 (1) with the N,N′-dimethyl-4,4′-bipyridinium cation obtained in situ, was synthesized and characterized by X-ray single-crystal diffraction method. The title compound is characteristic of an isolated structure. The anions and cations in 1 are connected through hydrogen-bonding interactions to give a two-dimensional (2-D) supramolecular layer. The fluorescence result discovers a wide emission band in the green region.
Two new competitive coordination-directed zinc(II) complexes, [Zn2(bpp)2(na)4]n (1) and [Zn(bpp)2(nas)2]n (2) (bpp = 1,3-bi(4-pyridyl)propane, na− = 1-naphthoate, and nas− = 2-aminonaphthalene-1-sulfonate), were hydrothermally synthesized by varying carboxylate- or sulfonate-containing coligands. Structural analyses reveal that complex 1 modified by terminal na− spacers possesses a bent one-dimensional chain bridged by ditopic bpp linkers. By contrast, complex 2 with two monodentate nas− ligands exhibits a two-dimensional layered structure extended by four equatorial bpp connectors. Obviously, the increase on the dimensionality of 2 than 1 is significantly resulting from the competitive coordination of the two mixed ligands with differently tunable binding groups to variable metal polyhedra. In addition, both complexes with analogously high thermal stability display strong fluorescent emissions at room temperature resulting from the ligand-to-metal or intraligand charge-transfer, suggesting their hopeful applications as efficient fluorescent materials.
The mesoporous TiO2 nanoflakes have been prepared by the hydrothermal method, which is using Ti(SO4)(2) as the titanium raw and KOH solution as alkaline medium. The TiO2 nanoflakes have been characterizated by transmission electron microscopy, X-ray powder diffraction, N-2 adsorption-desorption analysis, cyclic voltammetry, and cycle performance test. Electrochemical performance test shows that mesoporous TiO2 nanoflakes have high discharge specific capacity and good cycle performance. Discharge specific capacity for the first time is in 0.2 C ratio of 278.1 mAh g(-1). After 90 cycles, the discharge capacity reduces to 97.6% of the theoretical specific capacity.
In this work, well-defined silver dendrites were fabricated by a simple electroless, template-free, and surfactant-free replacement reaction method using Zn foil and AgNO3 as the precursors. The products were studied by X-ray diffraction, scanning electron microscopy, transmitting electron microscopy, selected area electron diffraction, and X-ray photoelectron spectroscopy. The effect of the reaction time on the formation of Ag dendrites was investigated, which will open a new way to synthesize silver dendrites as electrodes applied in the field of solar cells and QLEDs. An oriented attachment-based aggregation model has been proposed to rationalize the formation of Ag dendrites.
An orthogonal experiment design was adopted for synthesis and optimization of ZrO2-Based catalyst for coke oven gas CO shift. The influence of the operating parameters on catalytic properties was investigated, with a composition being similar to typical industrial heterogeneous catalysts for WGS process. The experimental CO conversion data was analyzed by marginal and variance analysis. The optimal operating parameters for ZrO2-Al2O3 based catalyst were suggested by CO conversion.
Zinc-silver incorporated rice husk silica catalysts were prepared by a simple sol-gel precipitation. The FT-IR and thermal analyses are confirms the complete removal of the template after calcination at 773 K. From the XRD pattern, it could observed that zinc and silver which incorporated into rice husk silica with its characteristic crystalline form. Methylene blue (MB) was used to evaluate the photocatalytic activity of the prepared samples. During photodegradation, concentration of methylene blue was decreased within 1 h under the studied reaction condition. The incorporation of silver ions on rice husk silica improves the crystalinity and activity.
N-doped mesoporous TiO2 was successfully prepared by using CH3NO2 as the nitrogen source and P123 as template. The materials were characterized by TEM, N-2 sorption, XRD, XPS, UV-vis DRS, and TG-DTA techniques. The photocatalytic activity of N-doped TiO2 was tested in elimination of gaseous methanol, formaldehyde, and BTX (benzene, toluene and xylene). The obtained N-doped mesoporous TiO2 materials have better photocatalytic activity than commercial photocatalyst (Degussa P25). Moreover, the N-doped mesoporous TiO2 photocatalysts are easy to prepare and have stable performance, high photocatalytic activity and long lifetime.
Isoquinolinium dichromate and isoquinolinium chlorochromate were found as efficient catalysts to trigger oxidative bromination and iodination of aromatic hydrocarbons with KBr/KI and KHSO4 under acid-free conditions. Reaction times reduced highly significantly under sonication, followed by corresponding mono bromo derivatives in very good yield with high regioselectivity.
