Non‐rotational Tucker3 core simplification

A simple and efficient approach is reported to estimate the sparsest Tucker3 model for a considered linear dependent multiway data array using PARAFAC profiles. Employing the least possible number of non‐zero core elements equal to the pseudo array rank of data, a better and easier interpretation of the data array is possible. The approach does not require any prior information. The type of rank deficiency, that is rank overlap or closure in different modes, and the Tucker3 core size can be determined from a congruency factor while running the algorithm. The replacement method (RM) of optimization is applied to determine the pattern (positions and values) of non‐zero elements in the sparsest core of the Tucker3 model. Full rank and rank deficient simulated data sets in different conditions as well as an experimental 3D fluorescence data set from gold nanoparticle (AuNP) interaction with HIV genome are successfully used for evaluating the performance of the algorithm. Copyright © 2016 John Wiley & Sons, Ltd.     

Auslander-Reiten Conjecture in a Dual Vein

Algebras and Representation Theory - We consider a dual notion of the famous Auslander-Reiten Conjecture in case of Noetherian algebras over commutative Noetherian rings. Firstly, in the...     

Effect of axial ligand on the electronic configuration, spin states, and reactivity of iron oxophlorin

Iron-oxophlorin is an intermediate in heme degradation, and the nature of the axial ligand can alter the spin, electron distribution, and reactivity of the metal and the oxophlorin ring. The structure and reactivity of iron-oxophlorin in the presence of imidazole, pyridine, and t-butyl isocyanide as axial ligands was investigated using the B3LYP and OPBE methods with the 6-31+G* and 6-311+G** basis sets. OPBE/6-311+G** has shown that the doublet state of [(Py)(2)Fe(III)(PO)] (where pyridines are in perpendicular planes and PO is the oxophlorin trianion) is 3.45 and 5.27 kcal/mol more stable than the quartet and sextet states, respectively. The ground-state electronic configuration of the aforementioned complex is π(xz)(2) π(yz)(2) a(2u)(2) d(xy)(1) at low temperatures and changes to π(xz)(2) π(yz)(2) d(xy)(2) a(2u)(1) at high temperatures. This latter electronic configuration is consistently seen for the [(t-BuNC)(2)Fe(II)(PO(?))] complex (where PO(?) is the oxophlorin dianion radical). The complex [(Im)(2)Fe(III)(PO)] adopted the d(xy)(2) (π(xz) π(yz))(3) ground state and has low-lying quartet excited state which is readily populated when the temperature is increased.     

Interleukin-12 plasmid DNA delivery using l-thyroxine-conjugated polyethylenimine nanocarriers

The influence of the hydrophilicity and length of the cation alkyl chain in imidazolium-based ionic liquids on the dispersability of ZnO nanoparticles by ultrasound treatment was studied by dynamic light scattering and advanced rheology. ZnO nanopowder synthesized by chemical vapor synthesis was used in parallel with one commercially available material. Before preparation of the dispersion, the nanoparticles characteristics were determined by transmission electron microscopy, X-ray diffraction, nitrogen adsorption with BET analysis, and FT-IR spectroscopy. Hydrophilic ionic liquids dispersed all studied nanopowders better and in the series of hydrophilic ionic liquids, an improvement of the dispersion quality with increasing length of the alkyl chain of the cation was observed. Especially, for ionic liquids with short alkyl chain, additional factors like nanoparticle concentration in the dispersion and the period of the ultrasonic treatment had significant influence on the dispersion quality. Additionally, nanopowder characteristics (crystallite shape and size as well as the agglomeration level) influenced the dispersion quality. The results indicate that the studied ionic liquids are promising candidates for absorber media at the end of the gas phase synthesis reactor allowing the direct preparation of non-agglomerated nanoparticle dispersions without supplementary addition of dispersants and stabilizers.     

A new laser dye with potential for high stability and a broad band of lasing action: Perylene-3,4,9,10-tetracarboxylic acid-bis-N,N′(2′,6′ xylidyl)diimide

We have obtained high gain lasing action from a dye in the calss of perylene-tetracarboxylic acid diimides. These dyes have been used in the past as microcrystalline pigments and more recently as molecularly dissolved fluors having both an orange absorption color and orange fluorescence. In dimethylformamide this dye absorbs with a main maximum at 527 nm, well coupled to the exciting radiation from a frequency-doubled YAG exciting laser. The dye lases primarily in the 0′→ 1″ satellite of the fluorescence band from 566–585 nm, with intermittent output pulses to 605 nm. While this dye overlaps the lasing bands of the rhodamine dyes, we believe that it may be considerably more stable than even Rhodamine 6G, the most stable of that class.     

Nitrous oxide dimer: observation of a new polar isomer

Spectra of the nitrous oxide dimer (N2O)2 are studied in the region of the N2O nu1 fundamental band around 2230 cm-1 using a rapid-scan tunable diode laser spectrometer to probe a pulsed supersonic jet expansion. The previously known band of the centrosymmetric nonpolar dimer is analyzed in improved detail, and a new band is observed and assigned to a polar isomer of (N2O)2. This polar form of the dimer has a slipped parallel structure, rather similar to the slipped antiparallel structure of the nonpolar form but with a slightly larger intermolecular distance. The accurate rotational parameters determined here should enable a microwave observation of the polar N2O dimer. The need for a modern ab initio investigation of the N2O-N2O intermolecular potential energy surface is emphasized.     

Dinuclear copper complexes of pyridylphenylphosphine ligands: Characterization of a mixed-valence Cu/Cu dimer

Homo bi-copper complexes [Cu₂{PhP(2-py)₂}₂(NO₃)₃] (1) and [Cu₂{P(2-py)₃}₂Cl₂] (2), were synthesized from the reaction of Cu(NO₃)₂·3H₂O and CuCl₂·2H₂O with their corresponding 2-pyridylphosphine ligands. Compound 1 has a mixed valence Cu(I)-Cu(II) core with electron acceptor phosphine atoms and two NO₃⁻ anions coordinated in a monodentate fashion to Cu(I), giving it a distorted tetrahedral geometry. The environment of Cu(II) in 1 is composed of four nitrogen atoms from pyridyl and another NO₃⁻ anion in a square pyramidal geometry. This complex shows luminescence and a low energy absorption band at 969 nm corresponding to intermetallic electron transfer between the copper centers. Complex 2 was prepared from the treatment of copper(II) chloride with tris(2-pyridyl)phosphine, producing a binuclear copper complex which possesses a crystallographic inversion center. The copper geometry in this complex is distorted tetrahedral with coordination of one Cl⁻, two nitrogens from one bridging tris(2-pyridyl)phosphine ligand and one P atom from the other bridging tris(2-pyridyl)phosphine ligand, in a similar way observed in related complexes. The products have been characterized by spectroscopic methods and also by the single-crystal X-ray diffraction method.     

Chemical Recycling and Liquefaction of Rigid Polyurethane Foam Wastes through Microwave Assisted Glycolysis Process

Glycolysis of polyurethane rigid foams (PUFs) was performed utilizing microwave irradiation at atmospheric pressure. The effects of various metal hydroxide and acetate catalysts as well as different microwave powers were investigated. All reactions were monitored by FTIR spectroscopy. The recovered liquid product containing OH functional groups was applied as a portion of the polyol in formulation of a new polyurethane rigid foam product. The reactivity factors and densities were compared with the foam produced from totally virgin polyol.     

The cyclic CO2 trimer: observation of a parallel band and determination of an intermolecular out-of-plane torsional frequency

A new parallel (DeltaK=0) band of the cyclic CO(2) trimer is observed at 2364 cm(-1). The trimers are generated in a pulsed supersonic expansion from a slit-jet nozzle and probed with a tunable infrared diode laser. The band is assigned as a combination of an intramolecular CO(2) monomer nu(3) stretch and an intermolecular out-of-plane torsion, giving a torsional frequency of 12-13 cm(-1). The band is surprisingly strong and completely unperturbed, providing a rare and near perfect example for a parallel band of a symmetric top molecule with C(3h) symmetry and zero nuclear spins.