Proton Pump for O2 Reduction Catalyzed by 5,10,15,20‐Tetraphenylporphyrinatocobalt(II)

Oxygen reduction : A polarized water|1,2‐dichloroethane (DCE) interface acts as a proton pump for the [Co(tpp)] (TPP=5,10,15,20‐tetraphenylporphyrinato) catalyzed O₂ reduction by ferrocene (Fc) compounds to produce H₂O₂ (see figure; IT=ion transfer, ET=electron transfer). This system favours the collection of H₂O₂ by extraction immediately after its formation in DCE to the adjacent water phase.

     

A sol‐gel based solid phase microextraction fiber for the analysis of aliphatic alcohols in apple juices

A new fiber based on titania‐chitin sol‐gel coated on a silver wire for the headspace solid phase microextraction of aliphatic alcohols from apple juice samples was developed. The influences of fiber coating composition and microextraction conditions (extraction temperature, extraction time, and ionic strength of the sample matrix) on the fiber performance were investigated. Also, the influence of temperature and time on desorption of analytes from fiber were studied. Under the optimized conditions, a porous fiber with a high extraction capacity and good thermal stability (up to 250°C) was obtained. The proposed headspace solid‐phase microextraction‐GC method was successfully used for the analysis of aliphatic alcohols in apple juice and concentrate samples. The recovery values were from 92.8 to 98.6%. The RSD (n=5) for all analytes were below 7.8%.     

Spline Split Quaternion Interpolation in Minkowski Space

Spherical spline quaternion interpolation has been done on sphere in Euclidean space using quaternions. In this paper, we have done the spline split quaternion interpolation on hyperbolic sphere in Minkowski space using split quaternions and metric Lorentz. This interpolation curve is called spherical spline split quaternion interpolation in Minkowski space (MSquad).     

Common set of weights in data envelopment analysis: a linear programming problem

Data Envelopment Analysis is used to determine the relative efficiency of Decision Making Units as the ratio of weighted sum of outputs by weighted sum of inputs. To accomplish the purpose, a DEA model calculates the weights of inputs and outputs of each DMU individually so that the highest efficiency can be estimated. Thus, the present study suggests an innovative method using a common set of weights leading to solving a linear programming problem. The method determines the efficiency score of all DMUs and rank them too.     

Finding strong defining hyperplanes of Production Possibility Set

Production Possibility Set (PPS) is defined as the set of all inputs and outputs of a system in which inputs can produce outputs. Data Envelopment Analysis models implicitly use PPS to evaluate relative efficiency of Decision Making Units (DMUs). Although DEA models can determine the efficiency of a DMU, they cannot present efficient frontiers of PPS. In this paper, we propose a method for finding all Strong Defining Hyperplanes of PPS (SDHP). They are equations that form efficient surfaces. These equations are useful in Sensitivity and Stability Analysis, the status of Returns to Scale of a DMU, incorporating performance information into the efficient frontier analysis and so on.     

A three‐component process for the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivatives using nanosized nickel aluminate spinel crystals as highly efficient catalysts

NiAl₂O₄ spinel nanocrystals were synthesized as mesoporous catalysts and were fully characterized using Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray diffraction patterns (XRD), scanning electron microscopy (SEM), and Energy‐dispersive X‐ray spectroscopy (EDS). These nanocrystals catalyzed the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivatives via a one‐pot, three‐component condensation reaction of aromatic aldehydes, isatoic anhydride, and ammonium acetate or primary aromatic amine under microwave irradiation. By far, the most obvious advantages of the offered process are efficiency and recyclability of the catalyst as well as a significantly shorter reaction time.     

First principles study and comparison of vibrational and thermodynamic properties of XBi(X= In,Ga, B,Al)

In the present work, vibrational and thermodynamic properties of XBi(X = B, Al, Ga, In) compounds are compared and investigated. The calculation is carried out using density functional theory(DFT) within the generalized gradient approximation(GGA) in a plane wave basis, with ultrasoft pseudopotentials. The lattice dynamical properties are calculated using density functional perturbation theory(DFPT) as implemented in Quantum ESPRESSO(QE) code. Thermodynamic properties involving phonon density of states(DOS) and specific heat at constant volume are investigated using quasiharmonic approximation(QHA) package within QE. The phonon dispersion diagrams for InBi, GaBi, BBi, and AlBi indicate that there is no imaginary phonon frequency in the entire Brillouin zone, which proves the dynamical stability of these materials. BBi has the highest thermal conductivity and InBi has the lowest thermal conductivity. AlBi has the largest and GaBi has the smallest reststrahlen band which somehow suggests the polar property of XBi materials. The phonon gaps for InBi, GaBi, BBi and AlBi are about 160 cm~(-1), 150 cm~(-1), 300 cm~(-1), and 150 cm~(-1), respectively. For all compounds,the three acoustic modes near the gamma point have a linear behavior. C_V is a function of T~3 at low temperatures while for higher temperatures it asymptotically tends to a constant as expected.     

Thermosensitive molecularly imprinted poly(1‐vinyl‐2‐pyrrolidone/methyl methacrylate/N‐vinylcaprolactam) for selective extraction of imatinib mesylate in human biological fluid

The efficiency of a molecularly imprinted polymer as a selective packing material for the solid‐phase extraction of imatinib mesylate sorption was investigated. The molecularly imprinted polymer was prepared using N,N′‐methylenebisacrylamide as a cross‐linker agent, N‐vinylcaprolactam as a thermo‐sensitive monomer, 1‐vinyl‐2‐pyrrolidone and methyl methacrylate as functional monomers, azobisisobutyronitrile as an initiator and imatinib mesylate as a template. The drug‐imprinted polymer was identified by Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, and scanning electron microscopy. It was found that this polymer can be used for determination of trace levels of imatinib mesylate with a recovery percentage that could reach over 90%. Furthermore, the synthesized molecularly imprinted polymer indicated higher selectivity towards imatinib mesylate than other compounds. From isotherm study, the equilibrium adsorption data of imatinib mesylate by imprinted polymer were analyzed by Langmuir, Freundlich, and Temkin isotherm models. The developed method was used for determination of imatinib mesylate in human fluid samples by high performance liquid chromatography with excellent results.     

Silicene nanoribbon as a new DNA sequencing device

The importance of applying DNA sequencing in different fields, results in looking for fast and cheap methods. Nanotechnology helps this development by introducing nanostructures used for DNA sequencing. In this work we study the interaction between zigzag silicene nanoribbon and DNA nucleobases using DFT and non equilibrium Green's function approach, to investigate the possibility of using zigzag silicene nanoribbons as a biosensor for DNA sequencing.