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For the Al-alloyed 9Cr-ODS steels consolidated by spark plasma sintering and annealed at 800 °C, the Y-Al-O oxides, interface structure and orientation relationships between the oxides and the matrix are studied by high-resolution transmission electron microscope technique. It is found that the spark plasma sintering can serve as a useful and effective tool to investigate the transition states in complex oxide formation. Monoclinic Y4Al2O9 (YAM), orthorhombic YAlO3 (YAP), cubic Y3Al5O12 (YAG) and Y2O3 nanoparticles are identified. Both YAM and YAG can directly precipitate from the Y2O3 particles. One individual Y2O3 particle will produce several YAM particles, while only one YAG particle can be formed within one Y2O3 particle. The majority of identified Y-Al-O oxides exhibit partially coherent interfaces with the matrix, and multiple orientation relationships are revealed. [ABSTRACT FROM AUTHOR]

The syntheses and crystal structures of two cerium(IV) phosphonates are presented. Cerium(IV) bis(phenylphosphonate) Ce(O3PC6H5)21 can be formed from precipitation and mechanochemical reaction, whereas cerium(IV) bis(carboxymethylphosphonate) monohydrate Ce(O3PCH2COOH)2 · H2O 2 is only accessible via ball milling. All reactions proceed very fast and are completed within a short time span. In situ measurements for the syntheses of 1 show that the product occurs within seconds or a few minutes, respectively. The structures were solved from powder X-ray diffraction data. [ABSTRACT FROM AUTHOR]

It is demonstrated that the surface-relief orientation in the form of one-dimensional gratings with a period of 1.20 ± 0.02 μm formed under processing of hydrogenated-silicon films by femtosecond laser pulses (1.25 μm) with an energy density of 0.15 J/cm2 is determined by the direction of the polarization vector of the radiation and total laser exposure. Based on the results of the analysis of Raman spectra, the presence of a nanocrystalline phase of silicon with a volume fraction between 15 and 67% (depending on processing conditions) is detected. The observed processes of micro- and nanostructuring are caused by excitation of the surface plasmon-polaritons and nanocrystallization in the near-surface region in the field of high-power femtosecond laser pulses, respectively. In addition, formation of polymorph modifications of silicon Si-III and Si-XII under femtosecond laser processing with a number of pulses exceeding 500 is discovered. Anisotropy of the Raman signal for the above polymorph modifications is revealed. [ABSTRACT FROM AUTHOR]

A method to determine the orientation and diameter distributions of mineral wool fibre networks using X-ray tomography and image analysis is presented. The method is applied to two different types of mineral wool: glass wool and stone wool. The orientation information is obtained from the computation of the structure tensor, and the diameter is estimated by applying a greyscale granulometry. The results of the image analysis indicate the two types of fibres are distributed in a 2D planar arrangement with the glass wool fibres showing a higher degree of planarity than the stone wool fibres. The orientation information is included in an analytical model based on a Euler-Bernoulli beam approximation. The model enables prediction of the transverse stiffness. It is indicated that the glass wool transverse stiffness is lower than the stone wool transverse stiffness. Comparison with experimental results confirms the assumption that the underlying deformation mechanism of mineral wool is the bending of fibre segments between bonds. [ABSTRACT FROM AUTHOR]

In this study, the location, morphology and composition of the ω phase, which transformed from B2 phase in Ti-45Al-8.5Nb-(W, B, Y) (at.%) alloy, were investigated by short-time heat treatments in an intermediate temperature range. The results showed that the characteristics of B2 → ω phase transformation differ with the reduction in temperature. Below the ω solves, the B2 → ω phase transformation will take place within B2 area. There are existing two stages in the phase transformations during cooling from 850 to 700 °C. When the temperature is high (850 °C), granular ω populated along the dislocations existing in B2 phase and B2 grain boundaries, due to higher energy and the enrichment of Nb element at the B2/γ boundaries. It is worth noting that only two ω variants nucleate at 850 °C. With the decrease in temperature, the nucleation sites of ω phase would be migrated from the B2 boundaries to the inner area. At the temperature of 700 °C, four ω variants with different orientations nucleate homogenously within B2 grain. The ordered ω formation process of Ti-45Al-8.5Nb-(W, B, Y) alloy during cooling was postulated in this study. [ABSTRACT FROM AUTHOR]

Epitaxial MgSi films with (111) orientation were successfully grown at 300 °C on (001) AlO insulating substrates by RF magnetron sputtering method. The optimal conditions for the epitaxial growth were identified as a low deposition rate and high deposition pressure above 60 mTorr. X-ray diffraction and transmission electron microscopy analysis confirmed the growth of (111)-oriented epitaxial MgSi films with the following relationship: (111) MgSi//(001)AlO. The conduction type of the epitaxial films was p-type up to 450 °C, which is same conduction type of the (110)-one-axis oriented ones. The electrical conductivity of the epitaxial films was lower than that of (110)-one-axis oriented ones. [ABSTRACT FROM AUTHOR]

Magnetite FeO particles (M) were dispersed in polyvinyl alcohol (PVA) and oriented successfully by applying low external magnetic field. Observed orientation was verified by image analysis using ImageJ software. Crystallinity of the M/PVA samples was examined using DSC, showing a lower crystallinity by addition of particles and higher crystallinity resulting from orientation. Orientation of 0.05 and 0.1 wt% of M particles increased crystallinity of nanocomposites 39 and 57%, respectively. Tensile tests were also measured to examine the mechanical properties of oriented and non-oriented samples. Results show that the mechanical properties of samples including elongation at break and modulus had improved in the direction of oriented particles. Afterward, graphene oxide particles were magnetized [magnetic graphene oxide (MGO)] and dispersed in PVA resulting in improved mechanical properties. PVA/MGO nanocomposites showed better mechanical properties than PVA/M, although no improvement in the crystallinity was observed. [ABSTRACT FROM AUTHOR]

It is a great challenge for facile fabrication of thermal materials with both high thermal conductivity and excellent mechanical behaviors. Here, using tannic acid (TA) as a surface modifying agent, few-layer boron nitride nanosheets (BNNS) were effectively obtained by exfoliation of h-BN microplatelets through wet ball-milling. The existence of TA on the surface of BNNS also increased the dispersibility and stability in aqueous solution. By means of vacuum filtration of the dispersion of graphene oxide (GO) and BNNS, layered composite films of GO/BNNS were fabricated easily and at low cost. Because of the orderly orientation of GO and BNNS along the horizontal direction and high inherent thermal conductivity of the nanosheets used, a high in-plane thermal conductivity of 11.9 W/mK was reached with 80 wt% of BNNS. We also found that the thermal conductivity of the film could be further enhanced through adding 1.6 wt% PVA in the system to fill the voids between the nanosheets. The resulting composite film also exhibited excellent tensile strength of 41.0 MPa, flexibility potential for utilization on a curved surface, and electrical insulation up to 6.8 × 10 Ω cm. [ABSTRACT FROM AUTHOR]

The structural transformations in a nematic liquid crystal (NLC) layer with a hybrid orientation (planar director orientation is created on one substrate and homeotropic director orientation is created on the other) are studied. In the case of a dc voltage applied to the NLC layer, the primary instability is flexoelectric. It causes the appearance of flexoelectric domains oriented along the director on the substrate with a planar orientation. When the voltage increases further, an electroconvective instability in the form of rolls moving almost normal to flexoelectric domains develops along with these domains. Thus, the following spatially periodic structures of different natures coexist in one system: equilibrium static flexoelectric deformation of a director and dissipative moving oblique electroconvection rolls. The primary instability in the case of an ac voltage is represented by electroconvection, which leads to moving oblique or normal rolls depending on the electric field frequency. Above the electroconvection threshold, a transition to moving “abnormal” rolls is detected. The wavevector of the rolls coincides with the initial director orientation on the substrate with a planar orientation, and the projection of the director at the midplane of the NLC layer on the layer plane makes a certain angle with the wavevector. The results of numerical calculations of the threshold characteristics of the primary instabilities agree well with the obtained experimental data. [ABSTRACT FROM AUTHOR]

Background: Acyl hydrazones are an important class of heterocyclic compounds promising pharmacological characteristics. Malaria is a life-threatening mosquito-borne blood disease caused by a plasmodium parasite. In some places, malaria can be treated and controlled with early diagnosis. However, some countries lack the resources to do this effectively. Results: The present work involves the design and synthesis of some novel acyl hydrazone based molecular hybrids of 1,4-dihydropyridine and pyrazole ( 5a- g). These molecular hybrids were synthesised by condensation of 1,4-dihydropyridin-4-yl-phenoxyacetohydrazides with differently substituted pyrazole carbaldehyde. The final compound ( 5) showed two conformations (the major, E, s- cis and the minor, E, s- trans) as revealed by NMR spectral data and further supported by the energy calculations (MOPAC2016 using PM7 method). All the synthesised compounds were screened for their in vitro antimalarial activities against chloroquine-sensitive malaria parasite Plasmodium falciparum (3D7) and antimicrobial activity against Gram positive bacteria i.e. Bacillus cereus, Gram negative bacteria i.e. Escherichia coli and antifungal activity against one yeast i.e. Aspergillus niger. All these compounds were found more potent than chloroquine and clotrimazole, the standard drugs. Conclusions: In vitro antiplasmodial IC value of the most potent compound 5d was found to be 4.40 nM which is even less than all the three reference drugs chloroquine (18.7 nM), pyrimethamine (11 nM) and artimisinin (6 nM). In silico binding study of compound 5d with plasmodial cysteine protease falcipain-2 indicated the inhibition of falcipain-2 as the probable reason for the antimalarial potency of compound 5d. All the compounds had shown good to excellent antimicrobial and antifungal activities. [ABSTRACT FROM AUTHOR]

Electromagnetic emission (EME) generated by fracture of carbon fibre reinforced polymers (CFRP) is studied. The fracture is induced to cross-ply CFRP by mechanical loading in a three-point bending configuration. An EME acquisition set-up operating on the principle of capacitive coupling is used to measure the low frequency (kHz-MHz range) electric field whose generation is attributed to the charge redistribution accompanying the fracture processes. Multiple, differently oriented EME sensors, for the simultaneous EME measurement with different source-sensor orientations, were applied to account for the directionality of the EME sources and their generated electric fields. A method to deduce the crack orientation based on the emitted EME field's directionality is proposed. A comparison between the angles of the EME sources obtained by this method and the actual crack surface orientations as determined by computed tomography is made. [ABSTRACT FROM AUTHOR]

Background: The quinazoline are an important class of medicinal compounds that possess a number of biological activities like anticancer, anticonvulsant and antioxidant etc. Results: We evaluated the previously synthesized quinazoline derivatives 1- 3 for their anticancer activities against three cancer cell lines (HepG2, MCF-7, and HCT-116). Among the tested compounds, quinazolines 1 and 3 were found to be more potent than the standard drug Vinblastine against HepG2 and MCF-7 cell lines. All the tested compounds had less antioxidant activity and did not exhibit any anticonvulsant activity. Also, molecular docking studies were performed to get an insight into the binding modes of the compounds with human cyclin-dependent kinase 2, butyrylcholinesterase enzyme, human gamma-aminobutyric acid receptor. These compounds showed better docking properties with the CDK2 as compared to the other two enzymes. Conclusions: The overall study showed that thioxoquinazolines are suitable antitumor agents and they should be explored for other biological activities. Modification in the available lot of quinazoline and synthesis of its novel derivatives is essential to explore the potential of this class of compounds. The increase in the threat and with the emergence of drug resistance, it is important to explore and develop more efficacious drugs. [ABSTRACT FROM AUTHOR]

The evolution of misorientations at twin boundaries during hot deformations of austenitic steel was studied using electron backscatter diffraction and computer modeling with the purpose to explore the interrelation of this evolution with lattice rotations in grain interior. It was shown that a deformation-induced angular deviation from the initial twin misorientation turns out to be outside Brandon interval at many segments of the boundaries. The length fraction of these segments increases with strain, so that some twin boundaries transform to random ones at all their length. Statistical study shows that the most probable angular deviations are 9° and 13°, while the largest deviations are about 36° and 45° for the strain of 0.36 and 0.7, respectively. The experimental misorientation distributions were compared with theoretical ones computed using Taylor-type model. It was shown that deformation-induced misorientation changes are well described by the theory of polycrystals plasticity. At the same time, a discrepancy with the experiment occurs, which was proposed to be due to non-uniformity of grain lattice rotations. [ABSTRACT FROM AUTHOR]

Using transient hot disk technique to measure the thermal conductivity of liquids, the sensor is traditionally placed in the vertical orientation. In this study, the horizontal orientation method was analyzed. Effects of convection were studied and compared when using both the vertical and the horizontal orientation transient hot disk methods to measure the thermal conductivities of liquids. The temperature field and the velocity field of the testing fluid in both methods were obtained when numerical simulations were utilized to get quantified results of convection effects. Moreover, experiments were executed to validate the numerical simulation settings. The velocity magnitude and the Rayleigh number distribution were monitored in the direction which was perpendicular to the sensor face. It was found that the horizontal method had a lower maximum velocity and convection intensity. Besides, the testing region which was affected by heating process was smaller in horizontal method. The temperature distribution in horizontal orientation method showed asymmetry around the sensor face, the heat transfer ability of up face was higher than the down face. Meanwhile, the flow intensity in the horizontal orientation method grew faster than the vertical orientation method with long testing time. Judging from the average temperature rise of the sensor and the flow intensity in the fluid region, it is proposed that the horizontal orientation method is a better way for thermal conductivity measurements of liquids when testing time is not too long. Experiments were performed to measure the thermal conductivities of water, ethanol and glycol in both vertical and horizontal methods. It was found that the thermal conductivities measured in horizontal method were more accurate than the vertical method for all three liquid samples compared with the values in the literature. For ethanol, the relative error in the horizontal method is 11.6 % lower than the results in the vertical method. [ABSTRACT FROM AUTHOR]

Amechanism of local formation of crystals of random orientation in growth of single-crystal billets of refractory nickel alloys for blades of gas turbine engines is suggested. Aturn of the lattice is initiated at the place of contact between the initial melt and the surface of hard particles of NbC carbide and/or TiN nitride. [ABSTRACT FROM AUTHOR]

In this work, the reinforcing mechanism of β-form hybrid shish-kebabs induced by β-form nucleating agent (NA) on polypropylene (PP) tapes was revealed. The results showed a hierarchical orientation of fibrous crystalline profile and well-organized β-form PP lamellae existing in the β-form hybrid shish-kebabs, which exhibited remarkable reinforcing effect on the PP tapes in the orientated direction where the tensile strength increased from 44 to 54.7 MPa compared with isotropic one. However, when the tapes were strained perpendicular to the initial orientation, the tensile strength of NA-modified PP tapes decreased to 32.1 MPa. Theoretical analysis was conducted, and a new model was established to interpret this phenomenon. We suggest that specific layer structure constructed by well-organized lamellae and the tie molecules within the β-form hybrid shish-kebabs be responsible for the reinforcing effect due to the promoted fibrillation which stabilizes the crazing zone. [ABSTRACT FROM AUTHOR]

We report the formation and evolution mechanisms of HSFLs (high-spatial-frequency laser-induced periodic surface structures) on the commercial pure titanium under 10-ps 532-nm-wavelength laser irradiation. At a lower peak laser fluence, HSFLs in the rough zone are first formed along the surface texture. Subsequently, HSFLs in the flat zone are formed with an orientation parallel to the laser polarization direction. The formation of HSFLs can be attributed to the parallel orientation of the initial periodic modulation of the electron plasma concentration to the laser polarization direction. In particular, the formation of HSFLs along the surface texture occurs because the absorbed laser energy density is along the surface texture. At a higher peak laser fluence, two types of HSFLs appear together with LSFLs. The first type involves HSFLs that initially cover the concave part of the LSFL (low-spatial-frequency laser-induced periodic surface structures) and penetrate inward as the number of spot overlaps increases. This formation mechanism can be attributed to cavitation instability. The second type involves HSFLs that are initially in the convex part of the LSFL, and they are transformed into oxidized nanodots as the number of spot overlaps increases. The oxidized nanodots increase the absorption of laser energy in titanium, which leads to the ablation and removal of the oxidized material. Therefore, the surface of the LSFL becomes smooth. [ABSTRACT FROM AUTHOR]

The influence of the dissipation heating of a liquid filling a tube on the deformation, orientation, and distribution of liquid elements was investigated. Mathematical simulation of this process was performed on the basis of the equation of motion of the liquid and its continuity and energy equations with the initial and boundary conditions determined with account of the dependence of the viscosity of the liquid flow on its temperature, the presence of a free boundary in it, and the dissipation of its mechanical energy. The problem on the indicated liquid flow was solved numerically by the finite-difference method. The kinematics of this flow and its influence on the deformation and orientation of liquid elements was analyzed. The role of the viscous dissipation of the liquid in the formation of the thermomechanical history of the behavior of its elements in the process of filling of a tube with it is demonstrated. [ABSTRACT FROM AUTHOR]

The composition nonstoichiometry and structural quality of undoped gallium nitride layers grown by the hydride vapor phase epitaxy on sapphire substrates of different orientations have been estimated using Raman spectroscopy. It is found for the first time that the peak position of the phonon mode E (high) in the Raman spectra of gallium nitride films at a wave vector of 572 cm depends on the initial orientation of sapphire substrate and is low-frequency shifted when passing from Ga-polar to partially N-polar orientation. Additional modes are found in the spectra of GaN layers grown on substrates with m and r orientations. It is shown that a decrease in the composition deviation from stoichiometry, caused by reducing the HCl flow through the gallium source during the growth of GaN layers, leads to an increase in the phonon-mode intensity in the Raman spectrum. [ABSTRACT FROM AUTHOR]

In the present work, we report for the first time the formation of a dominant Dillamore orientation in a multilayered high-purity aluminum (99.99 %) subjected to an ultra-high von Mises strain of 11.2 by accumulative roll bonding (ARB). This multilayered aluminum with an average layer thickness of 180 nm was produced from an original aluminum sheet thickness of 100 μm. Microstructure and texture evolutions during ARB processes were investigated in detail and the formation of a dominant orientation is explained. The grain boundary spacing was observed to reduce with increasing number of ARB cycles. However, after 8 ARB cycles, the average grain boundary spacing was measured to be larger than the theoretical layer thickness. Also, a single and strong Cu orientation formed after an intermediate number (8-12) of ARB cycles, which rotated to a dominant Dillamore orientation with further ARB cycles. This is rationalized on the basis of three mechanisms: First, a homogeneous deformation causing lamella structure formation; second, the enhanced dynamic recovery of this pure aluminum through the movement of Y-type triple junction boundaries, resulting in grain coarsening; and third, the coarsening process eliminating the original few and small Brass and S lamellae and simultaneously enhancing the Cu and Dillamore orientations. [ABSTRACT FROM AUTHOR]

A comprehensive overview is given of the literature on slip transmission criteria for grain boundaries in metals, with a focus on slip system and grain boundary orientation. Much of this extensive literature has been informed by experimental investigations. The use of geometric criteria in continuum crystal plasticity models is discussed. The theoretical framework of Gurtin (J Mech Phys Solids 56:640-662, ) is reviewed for the single slip case. This highlights the connections to slip transmission criteria from the literature that are not discussed in the work itself. Different geometric criteria are compared for the single slip case with regard to their prediction of slip transmission. Perspectives on additional criteria, investigated in experiments and used in computational simulations, are given. [ABSTRACT FROM AUTHOR]

Selecting high molecular weight has become a quite popular approach for effective tuning of more shish-kebabs in semi-crystalline polymers. However, here, an unusual dependence of shish-kebabs on molecular weight of high-density polyethylene (HDPE) is found under the injection molding with a secondary flow. Characterization with electron microscope and X-ray scattering of the crystal structures reveals that the richest shish-kebabs develop in the HDPE with medium high molecular weight (HMW) chains rather than in the HDPE with more HMW chains. Both macroscopic scales (fluid behaviors related to the intensity of flow) and molecular scales (rheological properties related to orientation and relaxation) need to be overall considered and a physical model has been proposed to explain how the coupling between the chain architectures and the secondary flow field contributes to the unusual phenomenon. The factors, such as molecular parameters, interfaces between dispersed phase, and matrix as well as the properties of filler, profoundly influence both the two scales, which can be employed to tune the morphology related to physical properties. These significant results provide a simple but effective morphology control technique under a secondary flow field. [ABSTRACT FROM AUTHOR]

We prepared hydrogenated butadiene-acrylonitrile (HNBR) elastomer composites with random orientations of carbon nanotubes (CNTs) and aligned CNTs, denoted by random composites and aligned composites, respectively, by means of a simple mechanical blending method. The CNTs were dispersed uniformly in the HNBR matrix in both types of composites. Interestingly, at CNT contents of 1-2.5 vol%, the dielectric loss (tan δ) of the aligned composites increases slightly, and the dielectric constant ( ε′) of aligned composites increases largely with the increasing content of CNTs, whereas both the tan δ and the ε′ of the random composites increase largely with the increasing content of CNTs. As a result, a high ε′ (5000 at 1000 Hz) and a low tan δ (0.42 at 1000 Hz) were obtained in the aligned composite with a CNT content of 2.5 vol%, whereas a high ε′ and a high tan δ were obtained in the random composites. The relationship between the microstructure and dielectric properties was qualitatively analyzed by means of the percolation theory and intercluster polarization model. The mechanism for the achievement of high ε′ and low tan δ for dielectric composites was discussed. This study provides a guide to design microstructure that yields composites with improved dielectric properties. [ABSTRACT FROM AUTHOR]

The orientation behaviour of a range of high-density polyethylenes drawn to different draw ratios has been investigated by measurements of optical birefringence and wide-angle X-ray diffraction (WAXS). Consistent with previous research, it can be concluded that birefringence relates to the overall degree of orientation of the amorphous and crystalline phases, and is described to a good approximation by the pseudo-affine deformation scheme. The WAXS results show that crystalline orientation is also related uniquely to the applied strain and moreover is independent of the characteristics of the polymer concerned. It is shown that the crystalline orientation follows a new model based on the geometry of the crystalline slip mechanism where the crystalline phase deforms affinely in the longitudinal drawing direction. [ABSTRACT FROM AUTHOR]

Experiments were carried out on insulation foams of EPS and XPS in a small-scale flame spread experimental bench in the Tibetan plateau area of Lhasa and the plain area of Hefei both in China, respectively. The effects of altitude and sample orientation on flame spread behavior were quantitatively analyzed. The results show that extinction and secondary ignition occur for XPS on plateau, as the oxygen concentration in air entrainment is influenced by the generated smoke in the pool fire zone. The flame spread speed of EPS increases with the incline angle both in Lhasa and in Hefei, but for XPS (downward flame spread), the flame spread speed increases with the decrease in incline angle, especially in Lhasa. It is found that the heat transfer process is different for EPS and XPS. The transition fire zone plays an important role in heat transfer over XPS for downward flame spread resulting in total heat transfer including the flame convective and radiative heat $$ q_{\text{f}}^{\prime \prime } \delta_{\text{f}} $$ and the conductive heat $$ q_{\text{c}}^{\prime \prime } L $$ increase with the decrease in incline angle, while for EPS, the surface flame zone dominates the heat transfer in two places. [ABSTRACT FROM AUTHOR]

2- N-Tosylaminobenzaldehyde ferrocenoylhydrazone (HL) and the octahedral nickel(II) complex [Ni(HL)] · 2CHOH ( I) are synthesized and structurally characterized (CIF files CCDC 981876 (HL) and 981877 ( I)). The crystal structures of both compounds include two independent molecules with different mutual orientations of the tosyl and ferrocene fragments. In a single crystal of HL, the independent molecules are joined by intermolecular hydrogen bonds into infinite linear chains extended along the crystallographic axis x. The π-stacking interaction between the cyclopentadienyl rings is observed along with hydrogen bonds in a single crystal of complex I. [ABSTRACT FROM AUTHOR]

Ensembles of crystals of thin-plate martensite initiated by a strong magnetic field are analyzed within the concepts of the dynamic theory. It is shown that the laws detected agree with a specific dislocation scheme of arrangement of austenite subgrains with orientation {110}. [ABSTRACT FROM AUTHOR]

The magnetic structure of a quasi-one-dimensional frustrated NaCuO magnet single crystal is studied by NMR. The spatial orientation of the planar spin spirals in the copper-oxygen Cu-O chains is determined, and its evolution as a function of the applied magnetic field direction is analyzed. [ABSTRACT FROM AUTHOR]

Research in precision spraying investigates the means to reduce the amount of herbicide applied by directing droplets more accurately towards the weeds. The trend in the development of spot spraying equipment is an increase of the spatial resolution and new actuators that are able to target very small areas. However, there is a lack of methods for assigning rates of herbicides relating target to optimal droplet features. A wide range of droplet impact angles occurs during the spray application process because of droplet trajectories and the variability of leaf orientation. In this study, laboratory experiments were conducted to highlight the effect of surface orientation on droplet impact outcomes (adhesion, rebound or splashing) on two very difficult-to-wet surfaces: an artificial surface with a regular roughness pattern and an excised black-grass leaf with an anisotropic roughness pattern. Measurements were performed for different surface orientations with a high-speed camera coupled with backlighting LED. Droplets of two formulations (distilled water and distilled water + a surfactant) were produced with a moving flat-fan hydraulic nozzle to obtain a wide range of droplet sizes and velocities, which were measured by image analysis. Increasing surface angle reduces surface area available for droplet capture. Droplet impact behaviors are then modified since surface tilt induces a tangential velocity component at impact and, consequently, a reduction of the normal component. Impact modifications have also been observed due to the anisotropic roughness pattern of a black-grass leaf. The integration of droplet-surface interaction information offers a significant way to further improve the precision spraying efficiency by considering the optimal droplet size, speed and ejection angle depending on the target surface and architecture. [ABSTRACT FROM AUTHOR]

Dependences of single-electron charge transfer cross sections on the molecule orientation are studied in collisions between α-particles and H molecules in the ground state at collision energies E from 1 to 23 keV/u. Probabilities of single-electron capture were calculated in the independent electron approximation in the context of the close coupling equation method under the assumption that the hydrogen molecule consists of two independent hydrogen pseudoatoms. The total and partial single-electron capture cross sections averaged over all orientations of the molecule well agree with available experimental data at E > 5 keV/u. [ABSTRACT FROM AUTHOR]

The article focuses on the study which examines the effect of preorientation on the plastic deformation mechanism of poly(ethylene terephthalate) (PET) in adsorptive media. The study is investigated by polymer network deformation theory, shear flow, and differential scanning calorimetry. Results show that polymer orientation can improve the hardening of strain, increases content of fibrils in crazes, and reduces cavitation.

The orientation dependence of the Young's and shear moduli for ReN and ReN was examined in basal planes, pyramidal planes, and prismatic planes, and was strongly orientation-dependent on the prismatic and pyramidal planes. The elastic constants of the rhenium nitrides are characterized by the large values of the Young moduli and the large ratios of the shear modulus to bulk modulus, which is a signature of brittle materials. Elastic anisotropy, the nature of chemical bonding, and the electronic charge transfer between constituent atoms have also been explored to assess the origins of high elastic stiffness of these compounds. Their properties can be explained from the strength of bonding in rhenium nitrides ranked in the ascending order as: Re-Re (metallic), Re-N (ionic), and N-N (covalent). [ABSTRACT FROM AUTHOR]

The orientation relationships (ORs) of copper crystals on a (1120) sapphire substrate equilibrated at 1253 K are presented. They barely depend on the procedures used in sample preparation, i.e. dewetting of a copper film in the liquid state or in the solid state. The most frequent OR found is Cu(111) || AlO $$ (11\bar{2}0) $$ and Cu $$ [1\bar{1}0] $$ within few degrees from AlO[0001]. A secondary, lower frequency OR is also observed: Cu(001) || AlO $$ (11\bar{2}0) $$ with Cu $$ [1\bar{1}0] $$ within a few degrees from either AlO $$ [1\bar{1}00] $$ or AlO[0001]. These ORs do not follow the Fecht and Gleiter model which proposes that dense directions of the metal should align with dense directions of the oxide. On annealing, even at a temperature about half of the melting point of sapphire, fast diffusion of sapphire at the copper/sapphire interface is observed: the copper particles tend to achieve their interfacial equilibrium shapes by sinking into the substrate, and sapphire ridges form at the triple line. Finally, it is shown that the Cu(111) || AlO $$ (11\bar{2}0) $$ interface remains flat at the atomic scale, and is therefore part of the copper/sapphire equilibrium interfacial shape. [ABSTRACT FROM AUTHOR]

Crystals of a new rare-earth chain diborate TmH[BO], space group C2/ c, are obtained under hydrothermal conditions. The structure is determined without preliminary knowledge of the chemical formula. It is close to that of the GdH[BO] diborate studied earlier, but has a different orientation of the monoclinicity axis. In both structures the arrangement of atoms follows the pattern of the orthorhombic pseudosupergroup Cmca, which is most distinctly violated by the displacements of the rare-earth atoms. Their common anionic chain radical consists of diborate groups, namely, BO triangles and BO tetrahedra, 2[1T + 1Δ]. It is shown that the existence of two varieties that are based on the hypothetical orthorhombic prototype is determined by the pseudosymmetry and the difference between the ionic radii of the elements located at the middle and the end of the rare-earth series. The twinning and poor quality of the crystals are related to the effect of the m pseudoplane of the supergroup and cleavage. The structures of natural megaborates that contain diborate chains in complex boron-oxygen radicals are discussed. [ABSTRACT FROM AUTHOR]

The effects of electrohydrodynamic instability (EHDI) in smectic C liquid crystals in an electric field are studied. The objects of study are oriented layers of para-hydroxybenzoic acid possessing a smectic phase. The observed effects are divided into three groups according to the character of the motion of molecular centers of mass and the orientation of the director and the smectic C liquid crystal layers. The instabilities of the azimuthal and Kapustin-Williams domains are experimentally found. The experimental cell consists of two glass plates with tin dioxide electrodes separated by Mylar spacers of a specified thickness. Various schemes of domain rotation are considered. The EHDI is found to depend on the layer geometry. [ABSTRACT FROM AUTHOR]

The mutual relationship between phases in two-phase titanium alloys, αHCP and βBCC, is such that: {0001}||{110}; $$ \left\langle {11\bar{2}0} \right\rangle_{\user1{\alpha }} ||\left\langle {111} \right\rangle_{\user1{\beta }} $$, which in literature are known as Burgers orientation relationships. The coherency of the two phases is controlled by this crystallographic mutual relationship. Loss of coherency between phases during deformation can originate from a non-parallelism between the two boundary crystallographic planes. This study focuses on αHCP/βBCC interface coherency evolution in a lamellar Ti-6Al-4V alloy subjected to hot compression at 800 °C. The strain rate was 10 s and deformation was carried out to average true strains of ε = 0.29, 0.69, and 1.20. Loss of coherency was found at strains ε ≥ 0.50. For these strains, the lamellar α + β microstructure also evolved to a spheroidized morphology. The loss of interface coherency was thus associated with the acceleration of the lamellar microstructure dynamic spheroidization. [ABSTRACT FROM AUTHOR]

The article proposes mathematical model of heat exchange between open pitwall rocks and atmosphere for forecasting temperature field in permafrost strata, daily change in radiative balance, slope angle and surface orientation, and influence of contiguous benches. In terms of Udachny Open Pit Mine, time dependence of pitwall sloughing layer thickness is estimated under cyclic effect of freezing-defrostation in rocks having different freeze resistance. [ABSTRACT FROM AUTHOR]

Quasi-static orientation transitions in nematic-cholesteric liquid crystal (LC) droplets occurring in an isotropic environment in a constant electric field have been studied as dependent on the concentration of a chiral (cholesteric) dopant. In the case where the droplet radius is smaller than (or on the order of) the helix pitch induced by the chiral dopant ( R ≤ P), there exists a critical concentration of the dopant above which the interface with the isotropic phase initiates an increase in the deformation field with a correlation length dependent on the decreasing P value. [ABSTRACT FROM AUTHOR]

The variation of juvenile wood concentration within a southern pine feedstock can impact strand density variation during composite processing. Higher strand density variation can equate to increased variance in product performance and higher manufacturing costs. In this study, near-infrared spectroscopy coupled with linear and nonlinear methods of calibration was used to predict strand density. The best performing model was developed with a 1st derivative pretreatment and 6 factors including a quadratic term and exhibited a root mean square error of prediction (RMSEP) = 0.0566, R = 0.84, and a ratio of performance to deviation (RPD) = 2.30. When only the radial surface was presented and a linear model was utilized, the RMSEP was lowered to 0.033 and the RPD increased to 3.93 and confirmed that a random surface orientation will decrease model precision. The Box-Behnken design was found useful in providing a competitive nonlinear calibration model but with a smaller sample size. [ABSTRACT FROM AUTHOR]

In this paper, we examine the effects of aspect ratio and orientational order of nanoparticles on the dielectric properties of nanocomposites. The motivation is to clearly establish the effects of orientational order, since ambiguities exist in the literature. We focus on metallic nanoparticles, and show that, in the dilute concentration limit, theory, experiments and numerical simulations all unequivocally indicate that the effective dielectric constant increases with increasing aspect ratio and increasing degree of alignment of rod-like nanoparticles when they orient in direction of the electric field. [ABSTRACT FROM AUTHOR]

The coincidence site lattice (CSL) plays a similar role for grain boundaries (GB) as the crystal lattice plays for free surfaces. The most densely packed CSL is the twin-related CSL, characterized by an inverse density of coincidence sites Σ = 3. Phase diagrams in coordinates 'relative temperature T/ T-misorientation angle θ-inclination angle φ' were constructed for the twin GBs in Cu, Al, and Mo having different stacking fault energy γ. At low γ the twin GB remains faceted at all φ values and the number of crystallographically different facets increases with decreasing temperature. With increasing γ asymmetric twin GBs become more and more rough, and fewer facets appear with decreasing temperature. Also, with increasing γ the facets start to degenerate of into the first order rough-to-rough ridges. The behavior of twin GBs in Cu, Al, and Mo is compared with that of twin GBs in Zn. [ABSTRACT FROM AUTHOR]

Low intensity magnetic fields (22mT) rendered by a pair of bar magnets have been used to achieve in situ precise orientation of multiwalled carbon nanotubes (MWCNTs) and their directional deposition on solid substrates. The nanotubes were imparted magnetic characteristics through FeO (magnetite) nanoparticles covalently attached to their surface. The side walls of nanotubes were first acid oxidized with HSO/HNO (3:1 v/v) mixture and amine-functionalized magnetic nanoparticles were then interfaced to ends and side walls of the nanotubes through covalent linkages in the presence of a zero length cross linker, 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide. Fourier transformed infrared spectroscopic investigations affirmed the functionalization of nanostructures and formation of a magnetic nanohybrid. Transmission electron microscopy results revealed the attachment of nanoparticles along the side walls of MWCNTs. A flow cell was utilized to orient magnetic nanohybrid in the desired direction and also to create thin films of aligned MWCNTs. Further, directional assembly of magnetic MWCNTs at different orientation angles on solid substrates was studied by field emission scanning electron microscopy and optical microscopy. The procedure can be scaled to align CNTs on large surface areas for numerous applications, e.g., nanosensors, field emitters, and composites. [ABSTRACT FROM AUTHOR]

In this article, we present temperature and orientation study of iron phthalocyanine (FePc) thin films with different thickness deposited on silicon substrate. The organic thin films were obtained by the quasi-molecular beam evaporation. The micro-Raman scattering spectra of FePc thin layers were investigated in the spectral range 550-1,800 cm using 488-nm excitation wavelength. The Raman scattering and atomic force microscopy studies were performed at room temperature before and after annealing process. Annealing process of thin layers was carried out at 453 K for 6 h. From polarized Raman spectra using surface Raman mapping procedure the information on distribution of polymorphic phases of FePc layers has been carried out. Moreover, the obtained results showed the influence of the annealing process on the ordering of the molecular structure of thin films deposited on silicon substrate. For the very thin layers we did not observe the change of the polymorphic phase but only reordering of the thin layers and change of molecular structure to intermediate phase. Using atomic force microscopy method, we observed arrangement of the thin layers structure connected with the change of roughness of the thin layers after annealing process. The obtained results indicate that the structure of thin layer deposited on silicon substrate is strongly affected by the annealing process. [ABSTRACT FROM AUTHOR]

Many processes taking place in atmospheric aerosol particles are accompanied by changes in the particles' morphology (size and shape), with potentially significant impact on weather and climate. However, the characterization of dynamic information on particle morphology and position over multiple time scales from microseconds to days under atmospherically relevant conditions has proven very challenging. Here we introduce holographic imaging of unsupported aerosol particles in air that are spatially confined by optical traps. Optical trapping in air allows contact-free observation of aerosol particles under relevant conditions and provides access to extended observation times, while the digital in-line holographic microscope provides six-dimensional spatial maps of particle positions and orientations with maximum spatial resolution in the sub-micron range and a temporal resolution of 240 μs. We demonstrate the broad applicability of our approach for a few examples and discuss its prospects for future aerosol studies, including the study of complex, multi-step phase transitions. Obtaining dynamic information on atmospheric aerosol particle size and morphology is typically challenging. Here, the authors introduce holographic imaging of unsupported aerosol particles in air that are spatially confined by optical traps, allowing contact free observation over multiple timescales. [ABSTRACT FROM AUTHOR]

In the original article author name Qiangqiang Zhang was misspelled. It is correct here. [ABSTRACT FROM AUTHOR]

This paper presents our work on a pulsed single-frequency tunable optical parametric oscillator based on orientation-patterned gallium arsenide. Owing to crystal temperature tuning, this source covers the 10.2-11.2 and 7.6-8.6 μm ranges in single-longitudinal mode operation with a linewidth below 30 MHz. Standoff detection of ammonia around 10.35 and 10.5 μm is performed by implementing this source in an Integrated Path Differential Absorption Lidar (IP-DIAL) setup. [ABSTRACT FROM AUTHOR]

The article reports on the importance of increasing the surface coverage of either the rods or the underlying beads in the flocking transition of the materials for undergoing an aligned configuration and also discusses the role of hydrodynamic coupling in orientation of the colloidal particles.

A conference paper about the cross docking technique for the study of protein interaction is presented. It states that cross docking can be utilized as a reliable indicator for the selection of suitable protein conformations for ensemble based virtual screening. It also mentions that the currently applied characterization methods can not capture the differences in docking performance which are caused by minor conformational changes within the protein.