Interaction of z component of magnetic field between two samples of GO material in the round rotational single sheet tester (RRSST)

The magnetic properties of two grain-oriented (GO) samples of the same grade were measured under alternating and rotational magnetic flux conditions. Two samples were measured separately and then together in different arrangement to each other. The interaction of magnetic field between two samples were measured by using a coil, which was placed in between. The results show that the _Hz$H_z$ component influence measured magnetic properties in the x–y plane.     

Star Chromatic Index

The star chromatic index of a graph G is the minimum number of colors needed to properly color the edges of the graph so that no path or cycle of length four is bi‐colored. We obtain a near‐linear upper bound in terms of the maximum degree . Our best lower bound on in terms of Δ is valid for complete graphs. We also consider the special case of cubic graphs, for which we show that the star chromatic index lies between 4 and 7 and characterize the graphs attaining the lower bound. The proofs involve a variety of notions from other branches of mathematics and may therefore be of certain independent interest.     

Extremal generalized centralizers in matrix algebras

We describe matrices with extremal generalized centralizers over algebraically closed fields.     

Structural studies of some o-substituted S-phenyl thiobenzoates. I. Crystal structure of S-phenyl o-chlorothiobenzoate and S-phenyl o-bromothiobenzoate

Structural characteristics ofS-phenylo-chlorothiobenzoate (I) andS-phenylo-bromothiobenzoate (II) have been investigated by single crystal X-ray diffraction. It was shown that the crystals are isomorphous and crystallize in the monoclinic space groupP2₁ withZ=2. The unit cell parameters are:a=10.150(3),b=7.672(2),c=7.595(2) Å,=91.28(1)° for C₁₃H₉ClOS (compoundI) anda=10.141(3),b=7.764(2),c=7.653(2) Å,=90.14(3)° for C₁₃H₉BrOS (compoundII). The structures were solved by heavy-atom methods and refined by full-matrix least-squares, from room-temperature data collected with a Philips PW 1100 diifractometer, to conventionalR factors of 0.056 forI and 0.044 forII. The structures consist of independent molecules held together by intermolecular interactions. Molecular packing is influenced by the presence ofo-substituted Cl or Br atoms. The Cl atoms in structureI as well as the Br ones in structureII are directed to the centers of the pi-electronic system of theo-substituted phenyl rings belonging to the neighboring molecules. The six ClC and BrC distances range from 3.651(10) to 3.869(9) Å and from 3.644(6) to 3.890(6) Å, respectively. The C1 (or Br) atom is additionally directed towards the two carbon atoms (C3 and C4) in anothero-substituted phenyl ring, the C1lC and BrC distances being 3.786(9) and 3.849(10) Å inI and 3.727(6) and 3.881(6) Å inII. The torsion angle C6-C7-S-C8 is-170.2(7)° inI and 168.6(4)° inII. The angles between the planar O-C7-S central fragment of the molecule, on the one hand, and theo-substituted phenyl ring, on the other, are 113.9(3)° in I and 110.9(2)° inII. The corresponding values for the angles between the O-C7-S fragment and the nonsubstituted phenyl ring are 115.8(3)° and 114.3(2)° in compoundsI andII, respectively.     

A novel access to tetrahydro-beta-carbolines via one-pot hydroformylation/fischer indole synthesis: rearrangement of 3,3-spiroindoleninium cations

The two component one-pot hydroformylation/Fischer indole synthesis sequence of 2,5 dihydropyrroles and phenyl hydrazines allows a facile and convenient access to tetrahydro-beta-carbolines in moderate to good yields.     

Influence of chain length and degree of branching of alcohol + chlorobenzene mixtures on determination and modelling of V by CEOS and CEOS/G mixing rules

The densities of binary mixtures of (1-propanol, or 1-butanol, or 2-butanol, or 1-pentanol + chlorobenzene) have been measured at temperatures 288.15, 293.15, 298.15, 303.15, 308.15 and 313.15 K and atmospheric pressure while for the system (2-methyl-2-propanol + chlorobenzene) measurements were performed at the same pressure and temperatures 303.15, 308.15, 313.15, 318.15 and 323.15 K. All measurements were performed by means of an Anton Paar DMA 5000 digital vibrating-tube densimeter. Excess molar volumes V^E were determined and fitted by the Redlich–Kister equation. It was observed that in all cases, V^E increase with rising of temperature. The values of limiting excess partial molar volumes have been calculated, as well. The obtained results have been analysed in terms of specific molecular interactions present in these mixtures taking into consideration effect of the chain length of alcohols, degree of branching in the chain, relative position of the alkyl and OH group in an alcohol and the effect of temperature on them. In addition, the correlation of V^E binary data was performed with the Peng–Robinson–Stryjek–Vera cubic equation of state (PRSV CEOS) coupled with the van der Waals (vdW1) and CEOS/G^E mixing rule introduced by Twu, Coon, Bluck and Tilton (TCBT). Also, the possibility of cross prediction between V^E and VLE by means of the NRTL parameters of G^E model available in literature and those incorporated in the TCBT model was tested.     

TG-DTA-FTIR analysis and isoconversional reaction profiles for thermal and thermo-oxidative degradation processes in black chokeberry (<Emphasis Type="Italic">Aroniamelanocarpa</Emphasis>)

The thermal and thermo-oxidative processes in Aroniamelanocarpa (black chokeberry) were investigated using combined thermo-analytical (TG-DTA) and spectroscopic (FTIR) experimental techniques. Isoconversional analysis revealed that the process in an inert (argon) atmosphere was probably governed by chlorogenic acid degradation, where autocatalysis (described by the empirical ?esták-Berggren model) might occur due to water already present in the early stages of the process through hydrolysis. Thermal degradation is described by the intrinsic kinetic parameters, where the degradation rate increases proportionally with an increase in the heating rate. Under oxidative conditions, the process was found to be primarily driven by neochlorogenic acid degradation. The thermo-oxidative degradation of Aroniamelanocarpa fresh samples can be described by two competitive reactions, where it was established that a cyanidin-3-glucosylrutinoside degradation made a significant contribution to a comprehensive kinetics. This study showed the targeting of the neochlorogenic acid in Aroniamelanocarpa fresh samples to have a strong hydrogen-donating activity, thereby rendering it capable of very efficiently entrapping the peroxy radicals. Current research has demonstrated that the relative contribution of the two competitive reactions to the overall process is highly dependent on the heating rate of the system under consideration.     

C*-Convex Sets and Completely Positive Maps

We prove a geometric version of an operator valued Hahn–Banach theorem and use it to study sets K that are A-convex over a unital C*-algebra A in the sense that \({\sum_{j=1}^{n} a_{j}^{*}y_{j}a_{j}\in K}\) whenever \({y_{j}\in K}\) and \({a_{j}\in A}\) with \({\sum_{j=1}^{n}a_{j}^{*}a_{j}=1}\). We show how weak* compact such sets can be realized as concrete sets of unital completely positive maps. An application to C*-extreme points is also presented.