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• Wells-Dawson polyoxometalate containing Ni (II) counter-ion. • Magnetic studies of newly synthesized Wells-Dawson polyoxometalate. • Electrochemical studies of Wells-Dawson polyoxometalate. • Crystal structure of the new Wells-Dawson polyoxometalate. • Super capacitance of Wells-Dawson polyoxometalate. The monomeric Ni(II) containing Wells-Dawson polyoxometalate (POM) complex K 2 Rb 6 Ni 0.33 [P 2 W 18 O 62 ]Cl 2 ∼15·3H 2 O (K 2 Rb 6 –1) was synthesized, for the first time, by the reaction of [Ni 2 (µ-OH 2)(O 2 CCMe 3) 4 (HO 2 CCMe 3) 4 ] and K 6 [P 2 W 18 O 62 ]. 19H 2 O in an aqueous medium. The compound was characterized by elemental analysis, FTIR, TGA, and single-crystal XRD (trigonal, space group R 3 ¯ m , cell length a = 37.3660(4), b = 37.3660(4), c = 12.8340(2) Å, α = 90, β = 90, γ = 120°, V = 15,518.4(3), Z = 9) techniques. The oxidation state of Ni(II) was calculated through bond valence sum (BVS) calculations. The electrochemical study indicated the super capacitance behavior of POM K 2 Rb 6 –1, and its magnetic susceptibility study showed magnetization with a temperature range of 5 K-300 K. [Display omitted] [ABSTRACT FROM AUTHOR]

• The sandwich POM Na 14 [Co 3 O(H 2 O)(A-α-PW 9 O 34)2]·~29.5 H 2 O was synthesized. • Single crystal X-ray diffraction reveals a multinuclear [Co 3 O 13 core. • Efficient electron transfer is observed by cyclic voltammetry, with three reversible redox peaks. • Antiferromagnetic behavior is observed at higher temperatures, with a ferromagnetic transition at lower temperatures. A new trimeric Co(II) containing Keggin trilacunary polyoxometalate (POM) sandwich complex, Na 14 [Co 3 O(H 2 O)(A-α- PW 9 O 34) 2 ·~29·.5H 2 O (Na14-1) was synthesized by the reaction of [Co 2 (μ- OH 2)(O 2 CCMe 3) 4 (HO 2 CCMe 3) 4 and Na 9 [A-α-PW 9 O 34 ·7H 2 O. The compound has been characterized by elemental analysis, FTIR, TGA and single crystal XRD (Triclinic space group P- 1, a = 12.2204(8) Å, b = 16.7035(11) Å, c = 23.3466(16) Å, α = 78.448(2)°, β = 80.551(2)°, γ = 78.448(2)° and Z = 2). The POM was electrochemically active and its behavior was studied by cyclic voltammetry at different scan rates. Bond valence sum (BVS) calculation was used to determine the oxidation state of Co. The magnetic susceptibility study indicated antiferromagnetic interactions between Co(II) ions and at lower temperature ferromagnetic behavior dominant in the structure. [ABSTRACT FROM AUTHOR]

In the title compound, [PdCl2(C6H5ClN)(C18H15P)]·CH2Cl2, the four-coordinated PdII complex exhibits a nearly square-planar geometry. The Pd—N, Pd—P and two Pd—Cl bond lengths are 2.170 (3), 2.2322 (9) and 2.2910 (9)/2.3104 (9) Å, respectively, and the angles at PdII lie in the range 86.85 (3)–93.58 (4)°. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cannabis sativa non-edible seed oil as an efficient source for biofuel. • Synthesis of WO 3 nanoparticles to catalyze transesterification. • Use of Central Composite Design CCD for optimization reactions. • Optimum biodiesel yield of 91 wt% was obtained. • Fuel propertied of biodiesel matched well with international standards. Current study focuses on the utilization of non-edible oil seeds of Cannabis sativa as an economical feedstock for synthesizing high quality biodiesel using novel, green and extremely reactive tungsten oxide (WO 3) nano catalyst. The as synthesized green nanoparticles (NPs) were examined using Fourier-transform infrared spectroscopy (FT-IR), X-ray Diffraction (XRD), energy diffraction X-ray (EDX) and scanning electron microscopy (SEM). Results showed that WO 3 has spherical crystal structure with a diameter of 45 nm. Highest biodiesel yield (91 wt%) was achieved under dynamic conditions i.e. , 2 wt% catalyst, 1:7 oil to methanol molar ratio, 80 °C reaction temperature for 120 min. The reaction conditions were optimized via Response Surface Methodology. WO 3 NPs showed catalytic stability up to five rounds. The fuel characteristics of biodiesel met the values set by international standards. Non-edible Cannabis sativa seed oil and novel green WO 3 nano-catalyst are economical choices to assist the sustainable growth of biodiesel industry. [ABSTRACT FROM AUTHOR]

The current study focuses on the synthesis of Cerium oxide (CeO2) nanocatalyst via Tragacanth Gum (TG) using the wet impregnation method and its application for sustainable biodiesel production from a novel, non-edible Descurainia sophia (L.) Webb ex Prantl seed oil. The D. sophia seed oil has higher oil content (36 wt%) and free fatty acid (FFA) value (0.6 mg KOH/g). Innovative analytical methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy, were used to characterize the newly synthesized, environmentally friendly, and recyclable CeO2-TG phytonanocatalyst (FT-IR). The results show that the CeO2-TG phytonanocatalyst was 22 nm in diameter with a spherical shape outer morphology, while the inner structure was hexagonal. Due to low FFA content, the D. sophia seed oil was pretreated and transesterified via a single step. Using varying parameters, the optimized process variables were determined via Response Surface Methodology (RSM). The optimum process values were 8:1 methanol to oil molar ratio, 0.3 wt% catalyst concentration, 90 °C temperature, and reaction time of 210 min with 98% biodiesel yield. The recently created phytonanocatalyst was reliable and effective, with three times reusability in the transesterification reaction. Thin layer chromatography (TLC), FT-IR, gas chromatography–mass spectroscopy (GCMS), and Nuclear magnetic resonance (NMR) analyses were used to characterize the synthesized biodiesel. Physico-chemical properties of D. sophia biodiesel, i.e., Kinematic viscosity (4.23 mm2/s), density (0.800 kg/m3), pour point (−7 °C), cloud point (−12 °C), and flash point (73.5 °C) agree well with international biodiesel standards (ASTM-6751, 951), (EU-14214), and China (GB/T 20828) standards. The results show that the synthesized nanocatalyst demonstrated remarkable stability, indicating a bright future for industrial biodiesel production from low-cost feedstock. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and Lead (Pb) from industrial wastewater can bioaccumulate in the living organisms of water bodies, posing serious threats to human health. Therefore, efficient remediation of heavy metal ions of Cd (II) and Pb (II) in aqueous media is necessary for public health and environmental sustainability. In the present study, water stable Zirconium (Zr) based metal organic frameworks (MOFs) with SO 3 H functionalization were synthesized by solvothermal method and used first time for the adsorption of Cd (II) and Pb (II). Synthesis of UiO-66-SO 3 H, nano-sized (<100 nm) MOFs, was confirmed by FTIR, XRD, FESEM and BET. Effects of contact time, pH and temperature were investigated for adsorption of Cd (II) and Pb (II) onto SO 3 H-functionalized Zr-MOFs. The UiO-66-SO 3 H displayed notable rejections of 97% and 88% towards Cd (II) and Pb (II), respectively, after 160 min at 25 °C and pH (6) with an initial concentration of 1000 mg/L. Adsorption capacities of Cd (II) and Pb (II) were achieved as 194.9154 (mg/g) and 176.6879 (mg/g), respectively, at an initial concentration of 1000 mg/L. The Pseudo second-order kinetic model fitted well with linear regression (R2) of value 1. The mechanism was confirmed mainly as a chemisorption and coordination interaction between sulfone group (-SO 3 H) and metal ions Cd (IIa) and Pb (II). These results may support effective adsorption and can be studied further to enrich and recycle other heavy metals from wastewater. [Display omitted] • Zr-MOF functionalization was synthesized with solvothermal method. • It exhibited large surface area and more active binding sites for metal ions adsorption. • Effect of contact time, temperature and pH on adsorption of metal ions was discussed. • Kinetics and thermodynamics parametric study was performed. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, [PdCl2(C12H23N)(C18H15P)], the Pd atom is four-coordinate in a nearly square-planar environment, with Pd—Cl = 2.2974 (6) and 2.3055 (7) Å, Pd—N = 2.1573 (17) Å and Pd—P = 2.2504 (7) Å. Both cyclo­hexyl rings adopt chair conformations. [ABSTRACT FROM AUTHOR]

This study investigated the potential of nano-composite MgO, Al 2 O 3 -CaO and TiO 2 for efficient conversion of novel non edible seed oil of Silybum eburneum into liquid biodiesel. Silybum eburneum contains oil contents (37.7%) and low free fatty acid (FAA) value (0.16 mg KOH/g). The synthesized heterogeneous nano-catalysts were characterized using X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Energy Dispersive X-Ray Spectroscopy (EDX) and Scanning Electron Microscopy (SEM) techniques. The highest conversion efficiency was achieved (91% biodiesel yield) using MgO catalyst followed by Al 2 O 3 -CaO and TiO 2 at 0.1% catalysts loading. The optimized experimental variables comprised of molar ratio (1:3), temperature (70 ͦ C), reaction time (3 h.) and stirring rate (600 rpm) using reflux transesterification route. The XRD analysis showed the sizes of the crystal lattices with a sequence of 13 nm for MgO, 29 nm for Al 2 O 3 -CaO and 37 nm for TiO 2 which reveals that smaller the size of the crystal structure, higher will be the conversion efficiency. The SEM of MgO showed exclusively porous lamellar like smooth surface highly agglomerated with nano entities with a particle size of 50 ± 10 nm length or width and about 20 nm thickness. SEM images of Al 2 O 3 -CaO nano-particles showed the size range from 27 nm to 75 nm having irregular morphology including spherical as well as rod shape with smooth surface and different size. The diameter of the microsphere calculated was about 2–6 μm. SEM for TiO 2 demonstrated that the average size was from 68.7 nm to 87.3 nm with interring particle dimension. The shape was proved to be sponge-like with spherical nano-holes. The FT-IR and EDX analysis of the catalyst also supported the study results. Gas Chromatography Mass Spectroscopy (GC–MS), Nuclear Magnetic Resonance NMR and FT-IR results confirmed the conversion efficiency of applying nano-catalysts. The results observed a novel finding that the conversion efficiency may increase with reducing the size and increasing the surface area of the nano-heterogeneous catalysts. The prepared composites are cheaper and can be applied for industrial scale production of biomass energy making it more cost effective and economically feasible. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is among the most widespread toxic trace elements found in agricultural soils due to various anthropogenic activities. The role of micronutrient-amino chelates on reducing Cd toxicity in crop plants is recently introduced. The current study was conducted to highlight the role of foliar application of zinc-lysine (Zn-lys) complex on biochemical and growth parameters and Cd uptake in wheat ( Triticum aestivum ) grown in aged Cd-contaminated soil. Foliar concentration of Zn-lys (0, 10, 20, and 30 mg L −1 ) was applied at different time intervals (2nd, 3rd, 5th and 7th week of sowing) and plants were harvested at maturity. Folliar application of Zinc-lys significantly increased the photosynthesis, grain yield, enzyme activities and Zn contents in different plant tissues. Zinc-lys reduced Cd contents in grains, shoot and root as well as reduced the oxidative stress in wheat linearly in a dose-additive manner. Taken together, Zn-lys chelate efficiently improved wheat growth and fortified Zn contents while reduced Cd concentration in plant in a Zn-deficient Cd-contaminated soil. Although, health risk index (HRI) from the soil sampling area seems to be lower than <1 for Cd but may exceed due to long-term consumption of grains produced from such contaminated soil. Foliar applied Zn-lys reduced HRI which may help to reduce health risks associated with Cd. [ABSTRACT FROM AUTHOR]

The green macroalgae present in freshwater ecosystems have attracted a great attention of the world scientists for removal of heavy metals from wastewater. In this mesocosm study, the uptake rates of heavy metals such as cadmium (Cd), nickel (Ni), chromium (Cr), and lead (Pb) byOedogonium westi(O. westti) were measured. The equilibrium adsorption capabilities ofO. westtiwere different for Cd, Ni, Cr, and Pb (0.974, 0.418, 0.620, and 0.261 mgg–1, respectively) at 18°C and pH 5.0. Furthermore, the removal efficiencies for Cd, Cr, Ni and Pb were observed from 55–95%, 61–93%, 59–89%, and 61–96%, respectively. The highest removal efficiency was observed for Cd and Cr from aqueous solution at acidic pH and low initial metal concentrations. However, the removal efficiencies of Ni and Pb were higher at high pH and high concentrations of metals in aqueous solution. The results summarized that O. westti is a suitable candidate for removal of selected toxic heavy metals from the aqueous solutions. [ABSTRACT FROM PUBLISHER]

Abstract: The 1-(6-(quinoxalin-2-yl)pyridin-2-yl)ethanone was synthesized in order to prepare a series of N-(1-(6-(quinoxalin-2-yl)pyridine-2-yl)ethylidene)benzenamines (L1–L7), which provided new alternative N∧N∧N tridentate ligands coordinating with iron(II) and cobalt(II) dichloride to form complexes of general formula LFeCl2 (1–7) and LCoCl2 (8–14). All organic compounds were fully characterized by NMR, IR spectroscopic and elemental analysis along with and magnetic susceptibilities and metal complexes were examined by IR spectroscopic and elemental analysis, while their molecular structures (L1, L4, 1, 4, 10, 13) were confirmed by single crystal X-ray diffraction analysis. Upon activation with methylaluminoxane (MAO), all iron complexes gave good catalytic activities for ethylene reactivity (oligomerization and polymerization), while their cobalt analogues showed moderate activities toward ethylene oligomerization with modified methylaluminoxane (MMAO). Various reaction parameters were investigated for better catalytic activities, the higher activities were observed at elevated ethylene pressure. The iron and cobalt complexes with para-methyl substituents of aryl group linked on imino group showed highest activity. [Copyright &y& Elsevier]

The article reports a two-step synthesis of composite nanofibrous mats of polytetraflouroethylene/zinc oxide (PTFE-ZnO); first, emulsion electrospinning of precursor solution was performed to yield as-spun mats followed by heat treatment at 280 °C. The surface of pure PTFE nanofibrous mats was modified by varying the amount of ZnO loadings in the electrospinning solution from 10 to 20 wt.%. Physiochemical characterization of synthesized mats was performed by FESEM, EDX, AFM, FTIR, Raman, TGA and contact angle goniometry. It was observed that fiber mean diameter decreased from 0.243 ± 15.10 μm to 0.17 ± 30.50 μm, RMS roughness increased from 112 to 627 nm and CA improved from 102.56° to 121.55° with the rise in ZnO content up to 20 wt% compared to the pure PTFE mats. Higher surface area, roughness and hydrophobicity of PTFE-ZnO mats resulted into significantly enhanced adsorption ability of VOCs on their surfaces against three model VOCs, namely, toluene, acetone and formaldehyde. The results have demonstrated that surface adsorption capacity of tested VOCs has considerably increased to 10, 07 and 03 folds respectively for the nanofibrous mats containing 20 wt.% ZnO, compared to pure PTFE mats. Based on these findings, these nanofibrous mats can potentially be used as filters for VOCs and particulate removal from air in the processing industries. [ABSTRACT FROM AUTHOR]

The diminution of edible oils and increasing cost of edible oils and biodiesel have gained the interest of many researchers for non-edible oils as biodiesel feed stock. The major hurdle in the commercialization of biodiesel is the high cost of feedstock. Due to fast mushrooming of fast food centers, waste cooking oil is one of the most economical feedstock available for the biodiesel production. The high free fatty acid contents and moisture in the waste cooking oil hinders the homogenous transesterification for the commercial purposes. Mixed oxides of Cu with Ni and Ce were synthesized by co-precipitation method and their efficacy for the production of biodiesel from the waste cooking oil was inspected. The acid catalyzed heterogeneous transesterification of waste cooking oil was performed in the sealed container. It was also interesting to mention that no pre-treatment was executed for the waste cooking oil conversion to biodiesel. It was investigated that mixed oxide catalyst CuO-CeO2 proved to be the potential candidate in pilot scale biodiesel production from waste cooking oil having about 92% conversion rate. Comprehensive chemical analysis of biodiesel including NMR, GC-MS, and FT-IR supports our result. [ABSTRACT FROM AUTHOR]