Current Trends in the Application of Nanomaterials for the Removal of Pollutants from Industrial Wastewater Treatment—A Review

In the recent decades, development of new and innovative technology resulted in a very high amount of effluents. Industrial wastewaters originating from various industries contribute as a major source of water pollution. The pollutants in the wastewater include organic and inorganic pollutants, heavy metals, and non-disintegrating materials. This pollutant poses a severe threat to the environment. Therefore, novel and innovative methods and technologies need to adapt for their removal. Recent years saw nanomaterials as a potential candidate for pollutants removal. Nowadays, a range of cost-effective nanomaterials are available with unique properties. In this context, nano-absorbents are excellent materials. Heavy metal contamination is widespread in underground and surface waters. Recently, various studies focused on the removal of heavy metals. The presented review article here focused on removal of contaminants originated from industrial wastewater utilizing nanomaterials.     

Large Hexadecametallic {MnIII–LnIII} Wheels: Synthesis,Structural, Magnetic,and Theoretical Characterization

The synthesis, gas sorption studies, magnetic properties, and theoretical studies of new molecular wheels of core type {Mn^III₈Ln^III₈} (Ln=Dy, Ho, Er, Y and Yb), using the ligand mdeaH₂, in the presence of ortho‐toluic or benzoic acid are reported. From the seven wheels studied the {Mn₈Dy₈} and {Mn₈Y₈} analogues exhibit SMM behavior as determined from ac susceptibility experiments in a zero static magnetic field. From DFT calculations a S=16 ground state was determined for the {Mn₈Y₈} complex due to weak ferromagnetic Mn^III–Mn^III interactions. Ab initio CASSCF+RASSI‐SO calculations on the {Mn₈Dy₈} wheel estimated the Mn^III–Dy^III exchange interaction as ?0.1 cm^?1. This weak exchange along with unfavorable single‐ion anisotropy of Dy^III/Mn^III ions, however, led to the observation of SMM behavior with fast magnetic relaxation. The orientation of the g‐anisotropy of the Dy^III ions is found to be perpendicular to the plane of the wheel and this suggests the possibility of toroidal magnetic moments in the cluster. The {Mn₈Ln₈} clusters reported here are the largest heterometallic Mn^IIILn^III wheels and the largest {3d–4f} wheels to exhibit SMM behavior reported to date.     

Effect of wood sawdust filler on the mechanical properties of Indian mallow fiber yarn mat reinforced with polyester composites

The research article focused on the effect of wood sawdust as secondary filler reinforcement in Indian mallow fiber yarn mat reinforced with polyester composites. Composites were fabricated along the transverse and longitudinal orientation in six different combinations by compression molding machine. The mechanical properties of composites by single and double layer yarn mat with and without wood sawdust filler were evaluated while loading composites specimen on warp and weft direction at the first time in this research paper. The Indian mallow fiber double layer longitudinal orientation yarn mat/wood sawdust filler/polyester composite specimen along the warp direction was found to exhibit optimum mechanical properties compared to other composites. Furthermore, the Indian mallow fiber yarn mat composites were fabricated with helmet and civil construction pipes at first time in this work to replace the synthetic fiber through natural fiber. Scanning electron microscopy was performed to study the morphologies of internal crack and fractured surface of composites.     

A Sharp Thermal Transition of Fast Aromatic‐Ring Dynamics in Ubiquitin

Aromatic amino acid side chains have a rich role within proteins and are often central to their structure and function. Suitable isotopic‐labelling strategies enable studies of sub‐nanosecond aromatic‐ring dynamics using solution NMR relaxation methods. Surprisingly, it was found that the three aromatic side chains in human ubiquitin show a sharp thermal dynamical transition at approximately 312 K. Hydrostatic pressure has little effect on the low‐temperature behavior, but somewhat decreases the amplitude of motion in the high‐temperature regime. Therefore, below the transition temperature, ring motion is largely librational. Above this temperature, a complete ring‐rotation process that is fully consistent with a continuous diffusion not requiring the transient creation of a large activated free volume occurs. Molecular dynamics simulations qualitatively corroborate this view and reinforce the notion that the dynamical character of the protein interior has much more liquid‐alkane‐like properties than previously appreciated.     

Assembly of lipophilic tetranuclear (Cu4 and Zn4) molecular metallophosphonates from 2,4,6-triisopropylphenylphosponic acid and pyrazole ligands

A sterically hindered aryl phosphonic acid ArP(O)(OH)2 (2) (Ar = 2,4,6-isopropylphenyl) was synthesized and structurally characterized. ArP(O)(OH)2 forms an interesting hydrogen-bonded corrugated sheet-type supramolecular structure in the solid-state. A three-component reaction involving ArP(O)(OH)2, 3,5-dimethylpyrazole(DMPZH), and Cu(CH3COO)2.H2O produces the tetranuclear Cu(II) compound [Cu4(mu3-OH)2{ArPO2(OH)}2(CH3CO2)2(DMPZH)4][CH3COO]2.CH2Cl2 (3). A similar three-component reaction involving ArP(O)(OH)2, 3,5-dimethylpyrazole, and Zn(CH3COO)2.2H2O yields the tetranuclear Zn(II) compound [Zn4{ArPO3}2{ArPO2(OH)}2{DMPZH}4(DMPZ)2].5MeOH (4). While 3 has been found to have an asymmetric cage structure where two dinuclear copper cores are bridged by bidentate [ArPO2(OH)]- ligands, 4 possesses an open-book tricyclic structure composed of three fused metallophosphonate rings. Magnetic studies on 3 revealed antiferromagnetic behavior.     

A simple, fast, and easy assay for transition metal-catalyzed coupling reactions using a paper-based colorimetric iodide sensor

A paper-based colorimetric iodide sensor (PBCIS) that consists of filter paper treated with starch and an oxidant is developed. It has been employed as a protocol to obtain the extent of conversion of aryl iodides in C-C, C-N, C-O and C-S bond formations, including polymer-supported Heck reactions, by transition metal catalysts such as palladium, nickel and copper.     

Multi-site coordination ligands assembled on organostannoxane supports

The reactions of bis(pyrazol-1-yl) acetic acid LCOOH (1) (L = (Pz)₂CH-) and bis(3,5-dimethylpyrazol-1-yl)acetic acid L′COOH (2) (L = (3,5-Me₂Pz)₂CH-) with organotin oxide (hydroxide) precursors, n-BuSn(O)(OH), n-Bu₂SnO, (n-Bu₃Sn)₂O and (Ph₃Sn)₂O has led to the isolation of several organotin compounds containing bispyrazolyl unit(s) on the periphery of the stannoxane structure [n-BuSn(O)O₂CL]₆ (3), [n-BuSn(O)O₂CL′]₆ (4), [n-Bu₃SnO₂CL]_n (5), [n-Bu₃SnO₂CL′]_n (6), [Ph₃SnO₂CL]_n (7), [Ph₃SnO₂CL′]_n (8), [{n-Bu₂SnO₂CL}₂O]₂ (9) and [{n-Bu₂SnO₂CL′}₂O]₂ (10). Compounds 5, 7, 9 and 10 have been structurally characterized by X-ray crystallography. In the solid state, these compounds possess interesting 3-D and 2-D supramolecular networks as a result of intermolecular C-H?O, C-H?N, C-H?Cl and C-H?π interactions.     

Evidence for interfacial-storage anomaly in nanocomposites for lithium batteries from first-principles simulations

We present theoretical support for a mass storage anomaly proposed for nanocomposites in the context of lithium batteries which forms the transition between an electrostatic capacitive mechanism and an electrode mechanism. Ab initio atomic and electronic structure calculations, performed on the Ti(0001)/Li2O(111) model interface, indicate the validity of the phenomenological model of interfacial Li storage and provide a deeper insight into the local situation. Beyond the specific applicability to storage devices, the possibility of a two-phase effect on mass storage generally highlights the availability of novel degrees of freedom in materials research when dealing with nanocomposites.