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While the development of chiral molecules displaying circularly polarized luminescence (CPL) has received considerable attention, the corresponding CPL intensity, glum, hardly exceeds 10−2 at the molecular level owing to the difficulty in optimizing the key parameters governing such a luminescence process. To address this challenge, we report here the synthesis and chiroptical properties of a new family of π-helical push–pull systems based on carbo[6]helicene, where the latter acts as either a chiral electron acceptor or a donor unit. This comprehensive experimental and theoretical investigation shows that the magnitude and relative orientation of the electric (μe) and magnetic (μm) dipole transition moments can be tuned efficiently with regard to the molecular chiroptical properties, which results in high glum values, i.e. up to 3–4 × 10−2. Our investigations revealed that the optimized mutual orientation of the electric and magnetic dipoles in the excited state is a crucial parameter to achieve intense helicene-mediated exciton coupling, which is a major contributor to the obtained strong CPL. Finally, top-emission CP-OLEDs were fabricated through vapor deposition, which afforded a promising gEl of around 8 × 10−3. These results bring about further molecular design guidelines to reach high CPL intensity and offer new insights into the development of innovative CP-OLED architectures., A CPL intensity of up to 3 × 10−2 is achieved in π-extended 6-helicene derivatives, owing to an intense helicene-mediated exciton coupling. Corresponding top-emission CP-OLEDs afforded a promising gEl of around 8 × 10−3.

The paper deals with the one-parameter family of Gordon–Schowalter objective derivatives including the Oldroyd, Cotter–Rivlin, and Jaumann derivatives. For a simple shear, movable bases are found in which the considered differential operators are reduced to the total time derivatives of the tensor components. For all derivatives of the family under consideration, except for Oldroyd and Cotter–Rivlin derivatives, the basis vectors lying in the shear plane rotate with a certain period changing their length and mutual orientation.

Strings of gold-organic oligomers of polar units have been formed by on-surface synthesis and investigated with non-contact atomic force microscopy. The mutual alignment of dipoles within the strings is analyzed. While an alternating head-to-tail alignment might be expected from dipolar interactions, a more complicated alignment order is observed. The data suggests that coordination bonding to additional gold adatoms leads to stabilization of parallel pairs of molecules, suppressing a head-to-tail alignment order.

The suggested approach allowed us to derive analytical expressions for modeling the shape of solid-echo signal and its time evolution for a system of three-spin groups with arbitrary constants of dipole–dipole interaction (DDI) in solids. Our method is based on the use of symmetry operations for spin exchange and spin flipping along the axis of initial polarization. Most useful seem to be the results on the shape solid echo signals. Upon comparison with experiment, our results may in turn be helpful in estimating a ratio of DDI constants and elucidating the mutual orientation of three-spin groups in a solid under study.

At biosynthetic production of hydrophobic recombinant proteins there is often a problem of their aggregation in so-called inclusion bodies, after which these proteins are difficult to renature. Obtaining such proteins in soluble forms is a formidable obstacle on the way of using them. One of possible solutions for this problem is the creation of fusion constructs with a leading protein. Previously, we have developed a system for biosynthetic production of insoluble hydrophobic proteins as a part of a fusion construct with a leader based on chaperone GroEL apical domain (GrAD, GroEL Apical Domain). Expressed as a part of a fusion with GrAD, two initially insoluble proteins were successfully obtained in soluble form. Still, such a system may have limitations in use, because supporting hydrophobic proteins in soluble state requires their interaction with GrAD substrate binding surface, which implies correct mutual orientation of proteins constituent parts of the construct, and for some target proteins such interaction may be sterically impeded. To enlarge the capability of using GrAD, the strategy of making permutations was used, which consists in linking original GrAD N- and C-termini with a linker and creating new N- and C-termini situated in closer proximity to the GrAD substrate binding surface. This work describes production and the study of physico-chemical properties of two permutated GrAD variants intended to be used as leaders in fusion constructs.

We have developed technology for manufacturing chains of CoFe/Al2O3/NiFe tunnel magnetoresistive (TMR) elements with pinning on the IrMn antiferromagnetic layer. We have studied the dependence of the shape of magnetoresistance curves on the geometric parameters of laterally bounded TMR contacts, as well as on the mutual orientation of the external magnetic field and the axis of unidirectional anisotropy of the pinned CoFe layer. The chain resistance ranges from several tens of kiloohms to hundreds of megaohms depending on the thickness of the tunnel-transparent dielectric layer with a magnetoresistive effect of 10–15%. The developed technology can be used in manufacturing tunneling magnetic field sensors.

The features of the influence of the Earth ionosphere on the radio wave propagation at the frequencies 200—1200 MHz are considered by the bicharacteristic method. The phase incursion and refraction errors are investigated. The values of the Faraday rotation angle depending on the mutual orientation of the ray trajectories and the vector of the intensity of the external magnetic field are estimated.

We refer to frequently used determinants suggesting dominant interactions between distant atoms in various dimers. First of all, we show, against the still‐prevailling opinion, that, in general, bond paths have nothing in common with dominant intermolecular interactions and therefore they are useless in such cases. Quite the contrary, reliable information about dominant intermolecular interactions can be obtained by means of electrostatic potential maps, which very convincingly explain mutual orientation of molecules in a dimer. For the first time, numerous examples of interactions that violate both the concept of privileged exchange channels proposed by Pendás and his collaborators as well as inequalities obtained by Tognetti and Joubert for the β parameter related to secondary interactions are presented. The possible cause of this violation is suggested. We also show that the so‐called counterintuitive bond paths result from quite natural behavior of the electron density gradient vector, i. e. searching for those areas of space that are characterized by large values of electron density or the most expanded its distributions.

We explore the potential of orientation-resolved pulsed dipolar spectroscopy (PDS) in light-induced versions of the experiment. The use of triplets as spin-active moieties for PDS offers an attractive tool for studying biochemical systems containing optically active cofactors. Cofactors are often rigidly bound within the protein structure, providing an accurate positional marker. The rigidity leads to orientation selection effects in PDS, which can be analyzed to give both distance and mutual orientation information. Herein we present a comprehensive analysis of the orientation selection of a full set of light-induced PDS experiments. We exploit the complementary information provided by the different light-induced techniques to yield atomic-level structural information. For the first time, we measure a 2D frequency-correlated laser-induced magnetic dipolar spectrum, and we are able to monitor the complete orientation dependence of the system in a single experiment. Alternatively, the summed spectrum enables an orientation-independent analysis to determine the distance distribution.

A rigid tetracene dimer with a substantial interchromophore distance has been prepared through the application of the recently developed catalytic arene-norbornene annulation (CANAL) reaction. An iterative cycloaddition route was found to be unsuccessful, and so a shorter route was adopted whereby fragments were coupled in the penultimate step to form 13 : 1 mixture of two diastereomers, the major of which was isolated and crystallized. Constituent tetracene moieties are linked with a rigid, well-defined bridge, and feature a near co-planar mutual orientation of the acenes.

We present an atomistic molecular dynamics study of self-assembled mikto-arm stars, which resemble patchy-like particles. By increasing the number of stars in the system, we propose a systematic way of examining the mutual orientation of these fully penetrable patchy-like objects. The individual stars maintain their patchy-like morphology when creating a mesoscopic (macromolecular) self-assembled object of more than three stars. The self-assembly of mikto-arm stars does not lead to a deformation of the stars, and their shape remains spherical. We identified characteristic sub-units in the self-assembled structure, differing by the mutual orientation of the nearest neighbor stars. The current work aims to elucidate the possible arrangements of the realistic, fully penetrable patchy particles in polymer matrix and to serve as a model system for further studies of nanostructured materials or all-polymer nanocomposites using the mikto-arm stars as building blocks.

In this work, the production of I111n radionuclide has been investigated theoretically via heavy-ion fusion reactions of two stable nuclei: C37l+G74e, M26g+R85b, S30i+B81r, and C46a+C65u reactions. Fusion cross-sections, barrier distributions, and potential energies on mutual orientations in the reactions planes of all reactions have been researched in detail around the barrier region via a coupled channel (CC) model using different codes. First of all, the most suitable codes and calculation parameter sets were determined through the C37l+G74e reaction, whose experimental data were available. The compatibility of the calculations via NRV knowledge base, CCFULL, CCDEF codes, and Wong’s formula with experimental data was analyzed. Barrier distributions and cross-sections for heavy-ion fusion reactions have been investigated with miscellaneous codes and vibrational-rotational nuclei combinations for interacting nuclei. Afterward, calculations were made with the determined parameter values for new reaction suggestions (M26g+R85b, S30i+B81r, and C46a+C65u reactions) and the results were compared. This study aims to suggest the new reaction combinations for the production of 111In radionuclide, to explore the impacts of different calculation codes and nuclear parameter combinations on the heavy-ion fusion cross-sections and barrier distributions, to demonstrate that the results are reliable, and to emphasize the importance of developing these studies in the preparation of new experiments.

Derivatives of 4-methyl-1,6-diphenylpyrimidine-2(1H)-selenone show very strong antimicrobial activity. In order to extend the current knowledge about the features responsible for the biological activity, crystal structure analyses are presented for 4-methyl-1-(2-methylphenyl)-6-phenylpyrimidine-2(1H)-selenone (1), 4-methyl-1-(3-methylphenyl)-6-phenylpyrimidine-2(1H)-selenone (2), 4-methyl-1-(4-methylphenyl)-6-phenylpyrimidine-2(1H)-selenone (3) (all C18H16N2Se) and 1-(4-chlorophenyl)-4-methyl-6-phenylpyrimidine-2(1H)-selenone (4) (C17H13ClN2Se). Furthermore, the antibacterial and antifungal activities of these compounds were evaluated. All the presented derivatives crystallize in the space group P21/c with one molecule in the asymmetric unit. The molecular geometries differ slightly in the mutual orientation of the rings. The packing of molecules in the crystals is dominated by C—H...N and C—H...Se intermolecular interactions. Additionally, in the crystal structure of 4, C—H...Cl intermolecular interactions are observed. The introduction of a methyl or chlorine substituent improves the biological activity, while its position significantly affects biological activity only in case of the chlorine substituent.

This paper exploits the Doppler and delay spreads for pedestrian-to-pedestrian (P2P) communications based on a measurement campaign carried out at 3.8 GHz. Several propagation conditions and different mobility patterns were investigated. In particular, the impact of vehicle passing in the vicinity of a P2P links was considered. It was found that the delay spread does not only depends on the propagation environment but also on the body mutual orientation whereas the presence of a moving vehicle in the vicinity of P2P links can have an impact on the Doppler spread.

We suggest a dynamical vector model of entanglement in a three qubit system based on isomorphism between $su(4)$ and $so(6)$ Lie algebras. Generalizing Pl\"ucker-type description of three-qubit local invariants we introduce three pairs of real-valued $3D$ vector (denoted here as $A_{R,I}$ , $B_{R,I}$ and $C_{R,I}$). Magnitudes of these vectors determine two- and three-qubit entanglement parameters of the system. We show that evolution of vectors $A$, $B$ , $C$ under local $SU(2)$ operations is identical to $SO(3)$ evolution of single-qubit Bloch vectors of qubits $a$, $b$ and $c$ correspondingly. At the same time, general two-qubit $su(4)$ Hamiltonians incorporating $a-b$, $a-c$ and $b-c$ two-qubit coupling terms generate $SO(6)$ coupling between vectors $A$ and $B$, $A$ and $C$, and $B$ and $C$, correspondingly. It turns out that dynamics of entanglement induced by different two-qubit coupling terms is entirely determined by mutual orientation of vectors $A$, $B$, $C$ which can be controlled by single-qubit transformations. We illustrate the power of this vector description of entanglement by solving quantum control problems involving transformations between $W$, Greenberg-Horne-Zeilinger ($GHZ$ ) and biseparable states., Comment: 26 pages, no figures; Accepted Phys. Rev. A 29Jul2020

The impact of the short-range interaction on the resonances occurrence in the anisotropic dipolar scattering in a plane was numerically investigated for the arbitrarily oriented dipoles and for a wide range of collision energies. We revealed the strong dependence of the cross section of the 2D dipolar scattering on the radius of short-range interaction, which is modeled by a hard wall potential and by the more realistic Lennard-Jones potential, and on the mutual orientations of the dipoles. We defined the critical (magic) tilt angle of one of the dipoles, depending on the direction of the second dipole for arbitrarily oriented dipoles. It was found that resonances arise only when this angle is exceeded. In contrast to the 3D case, the energy dependencies of the boson (fermion) 2D scattering cross section grows (is reduced) with an energy decrease in the absence of the resonances. We showed that the mutual orientation of dipoles strongly impacts the form of the energy dependencies, which begin to oscillate with the tilt angle increase, unlike the 3D dipolar scattering. The angular distributions of the differential cross section in the 2D dipolar scattering of both bosons and fermions are highly anisotropic at non-resonant points. The results of the accurate numerical calculations of the cross section agree well with the results obtained within the Born and eikonal approximations., Comment: 8 figures

Determination of the failure pressure of pipelines containing multiple corrosion defects is critical to the integrity and safety of the pipeline infrastructure. In this work, finite element models were developed to determine the failure pressures of X46, X60 and X80 steel pipelines containing multiple corrosion defects with varied geometries and orientations by assessing the mutual interaction of the defects and the effect on pipeline integrity. Generally, the failure pressure of corroded pipelines decreases with the increasing interaction effect between corrosion defects. The interaction effect mainly depends on the mutual orientation of the defects and their geometry and spacing, rather than the steel grade. For longitudinally and circumferentially aligned corrosion defects present on a pipeline, the interaction effect between them does not exist when their spacing is larger than 2.5 Dt and 5.3 t, respectively, where D and t are diameter and wall thickness of the pipeline. As a result, the multiple defects can be assessed individually. Compared to circumferential corrosion defects, the longitudinal defects are associated with a larger spacing where the interaction effect between corrosion defects exists. The circumferential spacing of corrosion defects has a less impact on the failure pressure of corroded pipelines compared with the longitudinal spacing. For pipelines containing overlapped corrosion defects, the failure pressure is lowered, compared to that in the presence of a single top layer defect only. An increase in the depth of either top or bottom layer corrosion defect reduces the failure pressure of the pipeline. The increased length of the defect also increases the interaction effect between the overlapped defects, lowering the failure pressure of the pipeline.

Theoretical calculations of the director distribution in a Grandjean–Cano wedge in relation to the anchoring strength and mutual orientation of the easy axes at the wedge surfaces are performed for various model surface anchoring potentials. Comparison of the theory and experiment allows one to propose the socalled model D-potential, quadratic in angle of director deviation from the easy axes, as the best one in fitting the experiment in the angular range of performed measurements. To satisfy general requirements on the wedge surface, a modified D-potential is proposed. The optimal conditions of the experiment aimed at restoring the potential in the whole range of its definition (in particular, nonparallel orientation of the easy axes at the wedge surfaces) are formulated.

This study analyzes difference in consumers’ and front-line workers’ perceptions on ‘consumer complaint behavior with hateful intentions’ though the Co-orientation Model in three dimensions. In addition, we seek to contribute to reducing the conflict between consumers and front-line workers in the service contact point by finding factors that affect the difference in perception between two parties. This study findings and implications are as follows. First, Taking a look at the mutual orientation between consumers and front-line workers, mutual perceptions have been found to match in agreement but with a significant difference in perceived agreement (congruence), which indicates that the internal perceptions of both consumers and front-line workers do not match. The findings confirm that consumers and front-line workers have different perspectives on consumer complaint behavior with hateful intentions and therefore raise a need for efforts and institutional devices for improvement. Second, the study has found that consumers’ economic responsibility as part of their social responsibilities and front-line workers’ perceptions on consumers’ civic responsibility affect the perception difference between these two groups and suggest a need for educating consumers about economic responsibility. Meanwhile, unlike consumers, front-line workers view consumers’ complaint behavior with hateful intentions from an ethical point of view, raising a need for a transition of perspectives on complaint behavior with hateful intentions.

A charring rate is a key parameter for the calculation of fire resistance of timber structures and for fire investigation. Charring rates are calculated from the char depth, and the time material is exposed to the heat load. The presented study deals with the calculation of the char depth of Norway spruce (Picea Abies (L.) Karst.) and Scots pine (Pinus Sylvestris L.) wood from the mass loss during the test on a cone calorimeter. The samples were loaded with the heat fluxes of 20, 30, 40 and 50 kW m−2 during a period of 10, 20 and 30 min. The samples were extinguished after the stated time intervals and subsequently the char depth was measured. The mutual orientation of the grain and the incident heat flux was parallel. A strong linear relation was found between the char depth and the ratio of the mass loss to density. The average charring rate decreases with the increasing time and increases with the increasing heat flux. The average charring rate of spruce wood was in the interval from 0.73 to 1.5 mm min−1. The average charring rate of pine wood was in the interval from 0.67 to 1.3 mm min−1.

We have studied phase transformations of a 20-μm-thick rolled foil of the Pd–57 at % Cu solid solution in a heating–cooling cycle. The as-prepared foil was two-phase, with a nanocrystalline structure. The mutual orientation of the α- and β-phases corresponded to the Nishiyama–Wassermann orientation relationship. Using X-ray diffraction and resistivity measurements, the β ⇆ α phase transformations were shown to be reversible. The effect of the severely deformed initial structure shows up as a shift in the onset temperature and end point of the α → β phase transformation.

The path of the Norrish–Yang reaction of methylammonium 4-(2,4,6-triisopropylbenzoyl)benzoate was studied by means of X-ray structure analysis. The following parameters influenced by this photochemical reaction were monitored: (a) intramolecular distances and angles in the reaction center, (b) the size of the free space near the reactive atoms, (c) the mutual orientation of molecular fragments, (d) the cell parameters, and (e) the product content. Product molecules were created in two modes, namely, by the reaction of the 2-isopropyl or 6-isopropyl group, which has not been revealed previously for other 2,4,6-triisopropylbenzophenones. The 2-isopropyl group took part in the photochemical reaction during the whole crystal transformation, whereas the reaction of the 6-isopropyl group started with a delay and ceased before the total crystal conversion. The reason for such behavior was explained by the analysis of changes in the free space near both o-isopropyl groups with the crystal phototransformation.

Introduction Septic coxitis is sustained in the early childhood and has a devastating effect on the musculoskeletal system. Systematization of the acquired defects and deformities is of great importance for treatment planning and outcome prediction. A radiographic classification based on the features of the deformities in the proximal femur and acetabulum as well as on their mutual orientation was proposed at the Russian Ilizarov Scientific Center for Restorative Traumatology and Orthopaedics. Purpose To study the reliability of the mentioned classification and to compare it with other classifications. Material and Methods Six orthopedic surgeons divided into two groups according to their specialization evaluated 23 X-rays of the hips using the classification systems of I.H. Choi, O.A. Sokolovsky, Е. Forlin, and RISC for RTO. Two orthopedic surgeons re-evaluated them two weeks later. Intra-rater and inter-rater agreement was determined using kappa value calculations. Results The number of inter-rater and intra-rater consensus depended on the specialization of experts, and it was higher in the first group. The highest proportion of the coincidences of three expert conclusions was observed when the classification systems of Forlin and RISC for RTO were used. The values of intra-rater and inter-rater reliability of the RISC for RTO classification were 0.542-0.641 and 0.436-0.738. Conclusion Taking into account a sufficient level of reliability, the RISC RTO classification can be used as a working system by planning surgical treatment and for prediction of its outcome in children with consequences of septic coxitis.

We study the offset fields affecting the free layer of perpendicularly magnetized tunnel junctions. In extended films, the free layer offset field results from interlayer exchange coupling with the reference layer through the MgO tunnel oxide. The free layer offset field is thus accompanied with a shift of the free layer and reference layer ferromagnetic resonance frequencies. The shifts depend on the mutual orientation of the two magnetizations. The offset field decreases with the resistance area product of the tunnel oxide. Patterning the tunnel junction into an STT-MRAM disk-shaped cell changes substantially the offset field, as the reduction of the lateral dimension comes with the generation of stray fields by the reference and the hard layer. The experimental offset field compares best with the spatial average of the sum of these stray fields, thereby providing guidelines for the offset field engineering., Special issue of J. Phys. D: Appl. Phys (2019) on STT-MRAM

Protein-docking is a molecular modeling problem which aims to predict, with computer science algorithms and techniques, the mutual orientation and position of two molecules forming a complex. One o ...

We demonstrate a Josephson junction with a weak link containing two ferromagnets, with perpendicular magnetic anisotropy and independent switching fields in which the critical current can be set by the mutual orientation of the two layers. Such pseudospin-valve Josephson junctions are a candidate cryogenic memory in an all superconducting computational scheme. Here, we use Pt/Co/Pt/CoB/Pt as the weak link of the junction with $d_\text{Co} = 0.6$ nm, $d_\text{CoB} = 0.3$ nm, and $d_\text{Pt} = 5$ nm and obtain a $60\%$ change in the critical current for the two magnetization configurations of the pseudospin-valve. Ferromagnets with perpendicular magnetic anisotropy have advantages over magnetization in-plane systems which have been exclusively considered to this point, as in principle the magnetization and magnetic switching of layers in the junction should not affect the in-plane magnetic flux., Comment: 5 pages, 3 figures

The peculiarities of interfacial boundary diffusion where the boundary goes between nonmiscible metals with body-centered cubic (BCC) and face-centered cubic (FCC) lattices have been studied taking, as a case in point, the Cu/Nb system, and using the molecular dynamics method. The diffusion atomic displacements were shown to occur mainly near the mismatch dislocations and their intersections. The diffusion of the high-melting component was found to be characterized by high anisotropy with the predominant atomic displacement along the dense-packed direction in the interfacial boundary plane being common to FCC and BCC lattices with the Kurdyumov–Sachs mutual orientation.

Fibre-reinforced elastomers are a class of elastomeric materials with peculiar mechanical properties. If the fibres are metallic or metallic-coated their orientation can be controlled by applying a magnetic field during the curing phase of the elastomer so to tailor the material anisotropy. Once the elastomer is cured, the application of a magnetic field may be used to control the deformation of the solid. In this paper, we aim at modelling both the pre-curing and post-curing phases within a unifying framework compatible with nonlinear elasticity and growth theory. The coupling between elasticity and magnetic field is obtained by considering a proper form of the free energy density which accounts for the mutual orientation between the magnetic field and the fibres. By considering some asymptotic limits, it is shown that the proposed approach incorporates both the usual magneto-elastic model of solids as well as those models used to study the magnetic reorientation of fibres in viscous solutions.

Method for determination of mutual orientation of inertial modules mounted on moving object remote from each other is proposed.