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Solid‐state cross‐polarization magic angle spinning (CPMAS) 13C NMR is employed to examine the morphological factors that contribute to the enhanced hole mobility observed in poly(3‐hexylthiophene) (P3HT) by the introduction of electrically inert poly(styrene) (PSt). Chain mobilities of crystalline and amorphous phases in the P3HT domain are evaluated utilizing T1C (13C spin‐lattice relaxation time in the laboratory frame). The crystallinity of P3HT component is estimated based on the spectral editing method through T1ρH (1H spin‐lattice relaxation time in the rotating frame) filtered CPMAS. Moreover, the miscibility of P3HT crystalline and P3HT amorphous domains is estimated. These results suggest the formation of the rigid amorphous (short‐range ordered amorphous) in a block copolymer (P3HT‐block‐PSt). An increase in the proportion of the crystallite and proximate presence of each crystallite in a blend sample of P3HT with PSt (P3HT‐blend‐PSt) are also indicated. Enhanced mobility is attributed to the larger portion of rigid amorphous domain for P3HT‐block‐PSt, and to higher crystalline content for P3HT‐blend‐PSt. [ABSTRACT FROM AUTHOR]

Flexoelectricity is the universal electric polarization of dielectrics upon exertion of a non‐uniform strain gradient. With the advancement of nano‐technology and miniaturization of electronic devices, flexoelectricity holds the promise to address the power requirements for such device operation. The direct flexoelectric effect in liquid crystal (LC) embedded poly(vinylidene fluoride) (PVDF) polymer films is examined for the first time by the application of external strain on the films. Physical characterizations such as Differential Scanning Calorimetry (DSC), dielectric spectroscopy, X‐ray diffraction, and field emission scanning electron microscopy (FESEM) are carried out to study the composite films' intrinsic and extrinsic properties like dielectric, crystallinity, and morphologies. The value of the flexoelectric coefficient (μ12) increases with the concentration of LC incorporation. At 3 wt%, μ12 attains a maximum value of 68 nC m−1, which is more than a threefold increase compared to that of the pure PVDF film. The role of Maxwell–Wagner–Sillars (MWS) polarization in determining flexoelectric polarization in polymer composites is also discussed. Moreover, the influence of the microstructure and domain size formation in determining the flexoelectric response are discussed in detail to infer the behavior of the flexoelectric coefficients of the films. Potential device applications based on this phenomenon have been proposed for future research in sensing and actuation. [ABSTRACT FROM AUTHOR]

Experiments on visually grounded, definite reference production often manipulate simple visual scenes in the form of grids filled with objects, for example, to test how speakers are affected by the number of objects that are visible. Regarding the latter, it was found that speech onset times increase along with domain size, at least when speakers refer to nonsalient target objects that do not pop out of the visual domain. This finding suggests that even in the case of many distractors, speakers perform object‐by‐object scans of the visual scene. The current study investigates whether this systematic processing strategy can be explained by the simplified nature of the scenes that were used, and if different strategies can be identified for photo‐realistic visual scenes. In doing so, we conducted a preregistered experiment that manipulated domain size and saturation; replicated the measures of speech onset times; and recorded eye movements to measure speakers' viewing strategies more directly. Using controlled photo‐realistic scenes, we find (1) that speech onset times increase linearly as more distractors are present; (2) that larger domains elicit relatively fewer fixation switches back and forth between the target and its distractors, mainly before speech onset; and (3) that speakers fixate the target relatively less often in larger domains, mainly after speech onset. We conclude that careful object‐by‐object scans remain the dominant strategy in our photo‐realistic scenes, to a limited extent combined with low‐level saliency mechanisms. A relevant direction for future research would be to employ less controlled photo‐realistic stimuli that do allow for interpretation based on context. [ABSTRACT FROM AUTHOR]

Recently, ternary solar cells have developed as a vital photovoltaic-technology since they combine the advantages of both single junction and tandem solar cells with their processing simplicity, mechanical flexibility, and lightweight. In this paper, we have investigated the role of domain size and the weight ratio of fullerene and non-fullerene acceptor on the performance of ternary blended PM6:Y6: PCBM organic solar cell. Using the effective medium approach and assuming the ternary blend of donor/acceptor1/acceptor2 nanocomposite as an effective integrated active layer, along with augmented Drift-diffusion formalism for the active layer of the organic solar cell, we have modeled the performance parameters of the device. The results show that the conversion efficiency of ternary solar cells depends on the distribution and size of both fullerene and non-fullerene acceptor domains. There are some optimal domain sizes where the optimum solar cell performance occurs. The obtained model results are in good agreement in comparison with experimental studies. [ABSTRACT FROM AUTHOR]

In this study, we comprehensively investigate the constant voltage stress (CVS) time-dependent breakdown and cycle-to-breakdown while considering metal-ferroelectric-metal (MFM) memory, which has distinct domain sizes induced by different doping species, i.e., Yttrium (Y) (Sample A) and Silicon (Si) (Sample B). Firstly, Y-doped and Si-doped HfO2 MFM devices exhibit domain sizes of 5.64 nm and 12.47 nm, respectively. Secondly, Si-doped HfO2 MFM devices (Sample B) have better CVS time-dependent breakdown and cycle-to-breakdown stability than Y-doped HfO2 MFM devices (Sample A). Therefore, a larger domain size showing higher extrapolated voltage under CVS time-dependent breakdown and cycle-to-breakdown evaluations was observed, indicating that the domain size crucially impacts the stability of MFM memory. [ABSTRACT FROM AUTHOR]

The current study investigates how speakers are affected by thesize of the visual domain during reference production. Previousresearch found that speech onset times increase along with thenumber of distractors that are visible, at least when speakersrefer to non-salient target objects in simplified visual domains.This suggests that in the case of more distractors, speakers needmore time to perform an object-by-object scan of all distractorsthat are visible. We present the results of a reference productionexperiment, to study if this pattern for speech onset times holdsfor photo-realistic scenes, and to test if the suggested viewingstrategy is reflected directly in speakers’ eye movements. Ourresults show that this is indeed the case: we find (1) that speechonset times increase linearly as more distractors are present; (2)that speakers fixate the target relatively less often in larger do-mains; and (3) that larger domains elicit more fixation switchesback and forth between the target and its distractors.

Herein, the morphological properties of polypropylene/polyolefin elastomer (PP/POE) composites with various rubber compositions are investigated by scanning electron microscopy (SEM). Further, to understand the relationship between the rubber domain size and the impact toughness of the PP composites, the phase structure and rubber particle size in the PP matrix are analyzed. The results indicate that an increased flowability of the rubber reduces the domain size, thereby enhancing the impact strength of the PP composite. In particular, the maximum impact strength of 76 kJ/m2 is obtained for the PP/POE composite in which an increased concentration of ethylene octene random copolymer (EOR) is used as the POE. The experimental results are in good agreement with the interparticle distance model for plastic/rubber blends. The results demonstrate that the rubber particle size in the polymer matrix is an important parameter for designing optimized thermoplastic elastomers. [ABSTRACT FROM AUTHOR]

This work represents a first step in the definition of a framework aimed at finding, by means of efficient global optimization based on metamodels, an optimal configuration of physical parameters for the ICON (ICOsahedral Nonhydrostatic) Limited Area Mode at high resolution (about 1.1 km) over Southern Italy, to be used for operational runs. The objective of the optimization is to reduce the distance between observed meteorological variables and modeled data. This distance is measured by an opportunely designed objective function. This work represents a preparatory step, since the input parameters considered are only a reduced number with respect to the huge amount of parameters potentially involved. First, domain size sensitivity was performed to choose the optimal domain. Then, the optimization was conducted by means of an Efficient Global Optimization algorithm relying on a Gaussian-based metamodel. The four parameters considered control the heat transfer in the turbulent layer, the laminar resistance and the snow vertical velocity. They were optimized over a week in November 2018, a period characterized by extreme events in the region considered. The results demonstrated the effectiveness of the proposed approach, reducing the distance from observed data, and the method can be considered promising from the perspective taking into account a larger set of physical parameters, and validation over a wider time-window. [ABSTRACT FROM AUTHOR]

PHB/bio-PBS and PHBV/bio-PBS blends have been comparatively evaluated for their thermo-mechanical, morphological and rheological properties. Differential scanning calorimetry indicated crystallisation of PHB and PHBV to be largely restricted, whereas the thermal stability of PHB and PHBV blends marginally increased upon blending with bio-PBS. The immiscibility of the two components of two blends influenced the morphological changes from domain-dispersed to co-continuous type where the domain sizes of the dispersed phase bio-PBS increased in tune with compositions. Dynamic mechanical analysis showed distinct glass transition relaxation peaks of two components whereas WAXD studies confirmed a sharper decline in crystallisation of the PHB/bio-PBS based blends than in PHBV/bio-PBS systems, though the lamellar sizes estimated from Scherrer's equation. At higher frequencies, the non-Newtonian melt flow dynamics of blends showed a sharp drop in their complex viscosity attributed to alignment of droplets along the flow direction (shear) due to phase separated morphology. Constitutive modelling of complex viscosity indicate the polymer melts to follow Carreau-Yasuda model, where the zero-shear viscosity decreased with bio-PBS content, irrespective of the nature of the matrix. Application of Cox-Merz rule has lead to estimations that PHB and PHBV matrices could give rise to co-continuous morphologies at a 35 wt. % and 41 wt. % of bio-PBS contents respectively. [ABSTRACT FROM AUTHOR]

In this study, we comprehensively investigate the constant voltage stress (CVS) time-dependent breakdown and cycle-to-breakdown while considering metal-ferroelectric-metal (MFM) memory, which has distinct domain sizes induced by different doping species, i.e., Yttrium (Y) (Sample A) and Silicon (Si) (Sample B). Firstly, Y-doped and Si-doped HfO2 MFM devices exhibit domain sizes of 5.64 nm and 12.47 nm, respectively. Secondly, Si-doped HfO2 MFM devices (Sample B) have better CVS time-dependent breakdown and cycle-to-breakdown stability than Y-doped HfO2 MFM devices (Sample A). Therefore, a larger domain size showing higher extrapolated voltage under CVS time-dependent breakdown and cycle-to-breakdown evaluations was observed, indicating that the domain size crucially impacts the stability of MFM memory.

This work represents a first step in the definition of a framework aimed at finding, by means of efficient global optimization based on metamodels, an optimal configuration of physical parameters for the ICON (ICOsahedral Nonhydrostatic) Limited Area Mode at high resolution (about 1.1 km) over Southern Italy, to be used for operational runs. The objective of the optimization is to reduce the distance between observed meteorological variables and modeled data. This distance is measured by an opportunely designed objective function. This work represents a preparatory step, since the input parameters considered are only a reduced number with respect to the huge amount of parameters potentially involved. First, domain size sensitivity was performed to choose the optimal domain. Then, the optimization was conducted by means of an Efficient Global Optimization algorithm relying on a Gaussian-based metamodel. The four parameters considered control the heat transfer in the turbulent layer, the laminar resistance and the snow vertical velocity. They were optimized over a week in November 2018, a period characterized by extreme events in the region considered. The results demonstrated the effectiveness of the proposed approach, reducing the distance from observed data, and the method can be considered promising from the perspective taking into account a larger set of physical parameters, and validation over a wider time-window.

The relatively low thermal depolarization temperature ( T d ) has hindered the development and practical application of lead-free Bi 0.5 Na 0.5 TiO 3 -based systems; therefore, a feasible strategy is urgently needed to defer the depolarization behavior. In this work, a perovskite/metal 0.78 Bi 0.5 Na 0.5 TiO 3 -0.22 Bi 0.5 K 0.5 TiO 3 / x Ag) composite ceramic is designed and successfully prepared. The introduction of metal Ag with a larger thermal expansion coefficient leads to an increased fraction and enhanced lattice distortion of the rhombohedral phase, as well as an enlarged domain size. The thermal stability thus is effectively improved, and the optimal x Ag) composite ceramic is designed and successfully prepared. The introduction of metal Ag with a larger thermal expansion coefficient leads to an increased fraction and enhanced lattice distortion of the rhombohedral phase, as well as an enlarged domain size. The thermal stability thus is effectively improved, and the optimal T d value of 166 °C is obtained at x = 0.03, which is about 60 °C higher than that of prototype ceramics. This research provides a perovskite/metal composite scheme to increase the depolarization temperature of BNT-based ceramics and promotes their potential for practical applications.

Distortion and fatigue are both important criteria for evaluating carburizing and quenching process. An optimized process was proposed to reduce distortion and improve fatigue strength simultaneously. Mild steel 20MnCrS5 were heat treated using standard condition and optimized condition respectively. The microstructure, hardness, residual stress, domain size, fatigue performance and crack growth rate with different conditions were studied. Due to carburization, the near surface of the materials have different microstructures with different carbon concentration. The carburized layer, subsurface layer and central layer were selected to prepare the fatigue specimens and to be evaluated. The strengthening effect was verified by comparing the fatigue limit and the crack growth rate. The strengthening mechanism was analyzed by comparing microstructure, retained austenite, residual stress and domain size. The results show that with the optimized condition the fatigue performance at different layers are improved while achieving higher surface hardness. The joint action of domain refinement, more compressive residual stress and less retained austenite results in the strengthening.

As an emerging two-dimensional (2D) semiconductor material, monolayer MoS2 has recently attracted considerable attention. Various promising applications of this material have been proposed for electronics, optoelectronics, sensing, catalysis, energy storage, and so on. To realize these practical applications, high-quality and large-area MoS2 with controllable properties is required. Among the many different synthesis techniques, epitaxy provides a promising route for producing MoS2 monolayers. Here, we review the epitaxial growth of monolayer MoS2 on various substrates, with a particular focus on large-scale films with large domain sizes and high domain alignments. Finally, we offer perspectives and challenges for future research and applications of this technology. [ABSTRACT FROM AUTHOR]

Methylammonium lead iodide (MAPbI3) perovskite has garnered significant interest as a versatile material for optoelectronic applications. The temperature‐dependent photoluminescence (TDPL) and phase‐transition behaviors revealed in previous studies have become standard indicators of defects, stability, charge carrier dynamics, and device performance. However, published reports abound with examples of irregular photoluminescence and phase‐transition phenomena that are difficult to reconcile, posing major challenges in the correlation of those properties with the actual material state or with the subsequent device performance. In this paper, a unifying explanation for the seemingly inconsistent TDPL and phase‐transition (orthorhombic‐to‐tetragonal) characteristics observed for MAPbI3 is presented. By investigating MAPbI3 perovskites with varying crystalline states, ranging from polycrystal to highly oriented crystal as well as single‐crystals, key features in the TDPL and phase‐transition behaviors are identified that are related to the extent of crystal domain‐size‐dependent residual stress and stem from the considerable volume difference (ΔV ≈ 4.5%) between the primitive unit cells of the orthorhombic (at 80 K) and tetragonal phases (at 300 K) of MAPbI3. This fundamental connection is essential for understanding the photophysics and material processing of soft perovskites. [ABSTRACT FROM AUTHOR]

Unsaturated and saturated phospholipids tend to laterally segregate, especially in the presence of cholesterol. Small molecules such as neurotransmitters, toxins, drugs etc. possibly modulate this lateral segregation. The small aromatic neurotransmitter serotonin (5-HT) has been found to bind to membranes. We studied the lipid structure and packing of a ternary membrane mixture consisting of palmitoyl-oleoyl-phosphatidylcholine, palmitoyl-sphingomyelin, and cholesterol at a molar ratio of 4/4/2 in the absence and in the presence of 5-HT, using a combination of solid-state 2H NMR, atomic force microscopy, and atomistic molecular dynamics (MD) simulations. Both NMR and MD report formation of a liquid ordered (Lo) and a liquid disordered (Ld) phase coexistence with small domains. Lipid exchange between the domains was fast such that single component 2H NMR spectra are detected over a wide temperature range. A drastic restructuring of the domains was induced when 5-HT is added to the membranes at a 9 mol% concentration relative to the lipids. 2H NMR spectra of all components of the mixture showed two prominent contributions indicative of molecules of the same kind residing both in the disordered and the ordered phase. Compared to the data in the absence of 5-HT, the lipid chain order in the disordered phase was further decreased in the presence of 5-HT. Likewise, addition of serotonin increased lipid chain order within the ordered phase. These characteristic lipid chain order changes were confirmed by MD simulations. The 5-HT-induced larger difference in lipid chain order results in more pronounced differences in the hydrophobic thickness of the individual membrane domains. The correspondingly enlarged hydrophobic mismatch between ordered and disordered phases is assumed to increase the line tension at the domain boundary, which drives the system into formation of larger size domains. These results not only demonstrate that small membrane binding molecules such as neurotransmitters have a profound impact on essential membrane properties. It also suggests a mechanism by which the interaction of small molecules with membranes can influence the function of membrane proteins and non-cognate receptors. Altered membrane properties may modify lateral sorting of membrane protein, membrane protein conformation, and thus influence their function as suspected for neurotransmitters, local anesthetics, and other small drug molecules.

Unsaturated and saturated phospholipids tend to laterally segregate, especially in the presence of cholesterol. Small molecules such as neurotransmitters, toxins, drugs etc. possibly modulate this lateral segregation. The small aromatic neurotransmitter serotonin (5-HT) has been found to bind to membranes. We studied the lipid structure and packing of a ternary membrane mixture consisting of palmitoyl-oleoyl-phosphatidylcholine, palmitoyl-sphingomyelin, and cholesterol at a molar ratio of 4/4/2 in the absence and in the presence of 5-HT, using a combination of solid-state 2H NMR, atomic force microscopy, and atomistic molecular dynamics (MD) simulations. Both NMR and MD report formation of a liquid ordered (L o ) and a liquid disordered (L d ) phase coexistence with small domains. Lipid exchange between the domains was fast such that single component 2H NMR spectra are detected over a wide temperature range. A drastic restructuring of the domains was induced when 5-HT is added to the membranes at a 9 mol% concentration relative to the lipids. 2H NMR spectra of all components of the mixture showed two prominent contributions indicative of molecules of the same kind residing both in the disordered and the ordered phase. Compared to the data in the absence of 5-HT, the lipid chain order in the disordered phase was further decreased in the presence of 5-HT. Likewise, addition of serotonin increased lipid chain order within the ordered phase. These characteristic lipid chain order changes were confirmed by MD simulations. The 5-HT-induced larger difference in lipid chain order results in more pronounced differences in the hydrophobic thickness of the individual membrane domains. The correspondingly enlarged hydrophobic mismatch between ordered and disordered phases is assumed to increase the line tension at the domain boundary, which drives the system into formation of larger size domains. These results not only demonstrate that small membrane binding molecules such as neurotransmitters have a profound impact on essential membrane properties. It also suggests a mechanism by which the interaction of small molecules with membranes can influence the function of membrane proteins and non-cognate receptors. Altered membrane properties may modify lateral sorting of membrane protein, membrane protein conformation, and thus influence their function as suspected for neurotransmitters, local anesthetics, and other small drug molecules. [ABSTRACT FROM AUTHOR]

The paper discusses the relationship between rheology and morphology of immiscible polypropylene (matrix))/polycarbonate (dispersed phase) blends compatibilized with novel polypropylene-polycaprolactone block and graft copolymers. Transmission electron microscopy (TEM) experiments revealed uniform droplet morphologies and a reduction of the average size of the dispersed phase upon addition of the compatibilizer. The results suggested the influence of the molecular weight distribution (MWD)/chemical composition distribution (CCD) and topology of the compatibilizer on the compatibilizing performance. Graft copolymers were found to be most effective in reducing the size of the dispersed phase, whereas the performance of block copolymers appeared to be highly dependent on the block length of PP. Small-amplitude oscillatory rheological experiments revealed an increase in elasticity at low frequencies caused by the interfacial interactions induced by the compatibilizer. The effect was quantified using the relaxation time spectrums that displayed the additional peak at longer relaxation times via Gramespacher-Meissner method. Broadband dielectric spectroscopy (BDS) revealed the influence of the copolymer architecture and molecular weight of the polypropylene blocks on the properties of the interfacial polarization, which was in line with both rheology and morphology data. [ABSTRACT FROM AUTHOR]

Distortion and fatigue are both important criteria for evaluating carburizing and quenching process. An optimized process was proposed to reduce distortion and improve fatigue strength simultaneously. Mild steel 20MnCrS5 were heat treated using standard condition and optimized condition respectively. The microstructure, hardness, residual stress, domain size, fatigue performance and crack growth rate with different conditions were studied. Due to carburization, the near surface of the materials have different microstructures with different carbon concentration. The carburized layer, subsurface layer and central layer were selected to prepare the fatigue specimens and to be evaluated. The strengthening effect was verified by comparing the fatigue limit and the crack growth rate. The strengthening mechanism was analyzed by comparing microstructure, retained austenite, residual stress and domain size. The results show that with the optimized condition the fatigue performance at different layers are improved while achieving higher surface hardness. The joint action of domain refinement, more compressive residual stress and less retained austenite results in the strengthening. [ABSTRACT FROM AUTHOR]

Just as fine precipitate dispersions are sought for high yield strength in alloys, nanoscale, mixed-phase microstructures are sought for high electromechanical performance in oxide ferroelectric materials. Spinodal decomposition is an effective route to fine-scale alloy microstructures and is exploited commercially, for example, in bronzes. Spinodal decomposition has been linked to nanoscale ferroelectric microstructures, but a comprehensive analysis is missing. Here spinodal decomposition in ferroelectric crystals is analysed in 3D including the local electric field using the ferroelectric multi-phase field model for polymorphic phase boundary (PPB) systems. A polarisation consulate temperature T s p is identified: in single phase ferroelectric, T s p = T c w , and, in PPB ferroelectrics, T c w , ζ = 0 < T s p < T c w , ζ = 1 . The stability of fluctuations in polarisation depends on temperature, is isotropic in wavevector k → , and corresponds to 2D waves in ceramics. General predictions are summarised and specific predictions for single phase and a PPB system (1 − x)Ba(Zr 0.2 Ti 0.8)O 3 - x (Ba 0.7 Ca 0.3)TiO 3 (BZT-xBCT) are made. At 284 K , the minimum wavelength is l c r i t B T = 166 nm in BaTiO 3 and l c r i t P Z T = 1.70 nm in Pb(Zr,Ti)O 3 , suggesting that spinodal decomposition is less likely to be observed in BaTiO 3. For BZT-40BCT, the minimum observable wavelength at T P P B is ∼ 22 unit cells l c r i t B Z T − 40 B C T = 8.72 nm and presents a viable route to nanoscale rhombohedral + tetragonal microstructures. Domain size engineering by spinodal decomposition with controlled grain structures and quenching in oxide and organic ferroelectrics is identified as a new route to optimise performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Regional climate models (RCMs) are able to simulate small-scale processes that are missing in their coarser resolution driving data and thereby provide valuable climate information for climate impact assessments. Less attention has been paid to the ability of RCMs to capture large-scale weather types (WTs). An inaccurate representation of WTs can result in biases and uncertainties in current and future climate simulations that cannot be easily detected by standard model evaluation metrics. Here we define 12 hydrologically important WTs in the contiguous United States (CONUS). We test if RCMs from the North American CORDEX (NA-CORDEX) and the Weather Research and Forecasting (WRF) model large physics ensembles (WRF36) can capture those WTs in the current climate and how they simulate changes in the future. Our results show that the NA-CORDEX RCMs are able to simulate WTs more accurately than members of the WRF36 ensemble. The much larger WRF36 domain in combination with not constraining large-scale conditions by spectral nudging results in lower WT skill. The selection of the driving global climate model (GCM) has a large effect on the skill of NA-CORDEX simulations but a smaller impact on the WRF36 runs. The formulation of the RCM is of minor importance except for capturing the variability within WTs. Changing the model physics or increasing the RCM horizontal grid spacing has little effect. These results highlight the importance of selecting GCMs with accurate synoptic-scale variability for downscaling and to find a balance between large domains that can result in biased WT representations and small domains that inhibit the realistic development of mesoscale processes. At the end of the century, monsoonal flow conditions increase systematically by up to 30% and a WT that is a significant source of moisture for the Northern Plains during the growing seasons decreases systematically up to –30%.

New fitting analyses for peak shapes in a 2D reciprocal‐space map are demonstrated to evaluate the strain, strain distribution and domain size of a crystalline ultra‐thin (15 Å) film of β‐FeSi2(100) grown epitaxially on an Si(001) substrate, using grazing‐incidence X‐ray diffraction. A 2D Laue‐fit analysis taking into account instrument broadening and the double‐domain effect provides residual maps as a function of the inequivalent strains ϵb and ϵc along the b and c axes of β‐FeSi2, respectively (and domain size D), reflecting the probability of existence of homogeneous domains with fixed ϵb, ϵc and D, in addition to the most probable minimum residual. A 2D Laue fit with an inhomogeneous domain distribution provides a population map with ϵb and ϵc, reflecting strain components contributing to the film. The population map also leads to a reference residual as a guide for the strains contributing to the residual map. The advantages of the 2D Laue fits are discussed by comparison with the Scherrer, Williamson–Hall and Gaussian fitting methods for equivalent systems. The analyzed results indicate that the β‐FeSi2 nanofilm was considerably small strained, which was also confirmed by transmission electron microscopy, implying a weak interface interaction between the film and the substrate. [ABSTRACT FROM AUTHOR]

Highlights • Obtaining of demagnetized state by means of Kerr Microscopy. • Calculation of the prefactor x = 0.389 corresponding to the structure in magnetic field observed. • Extraction of an activation energy by fittings of relaxation curves. • Low value of an activation energy. • Large width of distribution of the energy barriers. Abstract We have used polar Kerr microscopy to study the magnetic domain structure in an ultrathin Au/Co(1 nm)/Au layer with perpendicular magnetic anisotropy. We present our demagnetization method of the sample. In the demagnetized state, we observed a dendritic domain structure. We theoretically calculated the lateral domain size in the demagnetized state by using two different models and we saw that the prefactor x = 0.389 corresponds to the domain structure observed. We used polar magneto-optical Kerr effect magnetometry (PMOKE) to study the magnetization reversal and to extract an activation energy E a in zero field and the width of the distribution of the energy barriers σ w. We correlated the dendritic domain structure observed with the large value of σ w. [ABSTRACT FROM AUTHOR]

This paper completes previous studies on the phase behaviour and microstructure of the quaternary microemulsion water – cyclohexane – n -octyl-β- D -glucoside (β-C 8 G 1) – geraniol. The properties of this system are almost insensitive to temperature, while they can be tuned easily by adding an alcohol as co-surfactant. The addition of the alcohol changes the composition of the interfacial film, which, in turn, is the tuning parameter for the quaternary system. Studies of the phase behaviour together with SANS and NMR measurements allow drawing a quantitative picture of how the domain size ξ , the curvature H , and the interfacial tension σ ab depend on the composition of the interfacial film. The SANS data of both oil-in-water and water-in-oil droplet microemulsions recorded near the emulsification failure boundary were evaluated with the Generalised Indirect Fourier Transformation (GIFT), revealing a growth towards cylindrical structures when approaching the respective critical end point. We will show that the general behaviour of ternary and quaternary systems is equal if the appropriate tuning parameters are chosen. In addition, we will show that it is possible to apply the scaling description derived for temperature-dependent ternary systems to composition-dependent quaternary systems: plotting the reduced domain size, the reduced curvature and the reduced interfacial tension against the proper reduced tuning parameter , i.e., either the reduced temperature or the reduced interfacial composition, leads to one master curve for all systems. [Display omitted] [ABSTRACT FROM AUTHOR]

The computational cost still remains a limiting factor for performing convection-permitting climate simulations. Choosing a model set-up with the lowest computational cost without deteriorating the model performances is, therefore, of relevance before starting any decadal simulations at convection-permitting scale (CPS). In this study three different strategies that aim at reducing this computational cost are evaluated. These strategies are (1) excluding graupel in the microphysical scheme, (2) reducing the nesting steps to downscale from ERA-Interim scale to CPS and (3) reducing the domain size. To test these strategies, the COSMO-CLM regional model was integrated over a four-month summer period for Belgium and evaluated using both radar and rain-gauges precipitation data. It was found that excluding the graupel parametrization at CPS induces a dry bias, but that excluding the graupel parametrization in the parent nest of the CPS simulation does not impact daily accumulated precipitation. In addition, it was also found that the best downscaling strategy is to use two nesting steps, in our case 25 km and 2.8 km. The 7 km nest was found to be redundant. Finally, it was found that a minimum distance of ~150$\sim 150$ km between the evaluation domain and the lateral boundary is needed for daily precipitation to converge towards observed values. This indicates that the domain size must be large enough for the model to spin-up convective precipitation and in our case a domain size of 180×180$180 \times 180$ grid-points was found to be necessary. Our recommendations for CPS simulations at lowest computational cost are therefore (1) to include graupel parametrization at CPS but not in the parent nest, (2) to use two nesting steps to downscale from ERA-Interim to CPS and (3) to use a domain size large enough to allow for 150 km spatial spin-up.

It is widely, but not universally, believed that the lipids of the plasma membrane are not uniformly distributed, but that “rafts” of sphingolipids and cholesterol float in a “sea” of unsaturated lipids. The physical origin of such heterogeneities is often attributed to a phase coexistence between the two different domains. We argue that this explanation is untenable for several reasons. Further, we note that the results of recent experiments are inconsistent with this picture. However, they are quite consistent with an alternate explanation, namely, that the plasma membrane is a microemulsion of the two kinds of regions. To show this, we briefly review a simplified version of this theory and its phase diagram. We also explicate the dependence of the predicted domain size on four physical parameters. They are the energy cost of gradients in the composition, the spontaneous curvature of the membrane, its bending modulus and its surface tension. Taking values of the latter two from experiment, we obtain domain sizes for several different cell types that vary from 58 to 88 nm.

Graphical abstract Highlights • Pore scale simulations of air-oil flow through fibrous and foam filters are performed. • Influence of domain size on the CFD predictions are characterized for the two filters. • Two phase flow is more sensitive to mesh/domain size compared to single phase flow. • CFD predictions are validated with measured saturation data for different velocities. • Statistical uncertainties can be reduced to under 10% with sizes between 50 and 100 d. Abstract Pore-scale filtration simulations require high spatio-temporal resolutions and significant computational effort, hence, keeping the domain size to a minimum is desirable. Previous studies have considered domains based on Brinkman length, or are limited by computing power, and little information is available for conditions involving high fluid saturation – typical of steady state mist filtration. In this study, simulations are performed to characterize the effect of domain size on pressure drop, residual saturation, liquid film thickness and interfacial area concentration, using virtual nonwoven and foam filters with similar micro-structural properties. Further, experiments using micro-CT are performed to validate the present computational simulations. It is found that two phase flow through filters are more sensitive to local geometric variations or mesh resolution in the porous media than single phase flow. Statistical uncertainties in the steady state quantities of less than ± 10% can be expected to cope with the increase in computing power required for practical mesh sizes. A computational domain size of about 50–100 × d (where d is the strut or fibre diameter) was found to be required for CFD for the operating conditions considered. [ABSTRACT FROM AUTHOR]

The sensitivity to model resolution and domain size of the regional climate model RegCM4 is examined in simulating a deficit (1987), excess (1988), and normal (1989) Indian summer monsoon (ISM) rainfall. The initial and boundary conditions are prescribed by the European Centre for Medium-Range Weather Forecasts ( ECMWF ) Interim reanalysis at 1.5° × 1.5° (EIN15). The model simulated precipitation is compared with India Meteorological Department (IMD) gridded precipitation data (0.25° × 0.25°) and other parameters are compared with EIN15. In the present study, eight different horizontal resolutions such as 60, 55, 50, 45, 40, 36, 27 and 18 km are used whereas four different domain sizes (D01, D02, D03, and D04; largest to smallest) centered at the Indian landmass are considered to investigate the model performance. Results illustrate that the RegCM4 has the capability to depict the important semi-permanent features of the ISM, however, skills vary with the resolutions and domain sizes. Experiments with different resolutions reveal that the lower (850 hPa) and upper (200 hPa) tropospheric circulations are stronger over the Arabian Sea and Bay of Bengal in the 36 and 40 km grid-spacing simulations and closer to EIN15, however, it is weaker in the high-resolution simulations at 27 and 18 km grid-spacing. The biases in vertically integrated moisture transport (VIMT) are positive in the model simulations with resolutions from 36 to 60 km, but, it is negative with 27 and 18 km grid resolution. The simulated precipitation intensity increases as one moves from coarse to higher resolution till grid spacing 36 km. The model efficiency reduces to simulate higher precipitation intensity over the maximum precipitation zones of India during summer monsoon season when grid spacing 27 km and 18 km are used. The overall performance is better with the use of 36–40 km grid spacing than other resolutions in simulating ISM and associated rainfall. The sensitivity of domain sizes is examined by confining the model resolution at 40 km. The model simulated meteorological parameters, as well as derived parameters (such as pattern and intensity of precipitation, geopotential height, relative humidity, air temperature, wind, and CAPE), are represented better in D02 than other domains. The present study proposes a Comprehensive Rating Matrices (CRM) to evaluate the model performance considering all experiments (horizontal resolution and domain size) and different homogeneous regions, including errors obtained using different statistical methods. The CRM and statistical based skill score (SS) suggest that the performance of RegCM4 is the best at 40 km horizontal resolution followed by 36 km and 45 km grid-spacing and the D02 domain is suitable for ISM simulation. [ABSTRACT FROM AUTHOR]

1 H spin-diffusion solid-state NMR, in combination with other techniques, was utilized to investigate the effect of molecular architecture, solubility parameter of hard and soft segments, and their length on the domain size, interphase thickness and degree of phase separation in polyurethane-ureas based on oligomeric 4,4′-diisicyanate diphenylmethane, methylene-bis-(2-chloroaniline) and polyols based on polyethylene oxide, polypropylene oxide and polybutadiene with different length. Polyurethane-ureas based on polyethylene oxide soft blocks did not form rigid domains as a result of absence of microphase separation. The domain sizes of the hard segments in polyurethane-ureas under study practically did not show any dependence on their composition, but interphase thicknesses are higher for systems based on polybutadiene soft blocks. This indicates that the degree of phase separation depends strongly not only on the binary thermodynamic interaction between hard and soft segments in polyurethane-ureas, but is also influenced by their molecular architectures in the experimental temperature range. [ABSTRACT FROM AUTHOR]

We address the task of modelling numerically turbulent flows within random arrays of circular cylinders, relevant for several industrial and environmental applications. Numerical simulations are employed to model infinite domains of randomly placed emergent and rigid cylinders validated by a laboratory database acquired by a PIV system. The main goals are: (i) to discuss the effect of the numerical domain size and the grid resolution on the first and second order moments; and (ii) to characterise the spatial distribution of mean flow and turbulence variables in the drag-wake controlled stratum. Five domains of different sizes (9–44 cylinders) and four grid resolutions were independently tested. The results show that the time-averaged velocity field and the Reynolds stress tensor were not significantly affected by the size of the tested numerical domains. The analysis of the grid resolution influence shows how the results improve with mesh refinement, while none of the tested meshes produces un-physical results. The present work provides guidance on the acceptable compromises, in terms of mesh resolution and domain size, when predicting, with eddy resolving computational fluid mechanics tools, first and second-order moments of turbulent flows within infinite arrays or randomly placed cylinders. [ABSTRACT FROM AUTHOR]

It is widely recognized that fullerene derivatives show several advantages as n-type materials in photovoltaic applications. However, conventional [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) exhibits weak absorption in the visible region, and poor morphological stability, due to the facile aggregation. For further improvement of the device performance and durability, utilization of n-type polymeric materials instead of PCBM is considered to be a good way to solve the problems. In this study, we fabricated completely polymer-based solar cells utilizing p- and n-type block copolymers consisting of poly(3-hexylthiophene) (P3HT) and poly{[N,N'-bis(2-octyldodecyl) naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} [P(NDI2OD-T2)], respectively, containing common polystyrene (PSt) inert blocks, which decreased the size of phase separated structures. Electron mobility in synthesized P(NDI2OD-T2)-b-PSt film enhanced by a factor of 8 compared with homopolymer. The root mean square roughness of the blend film of two block copolymers (12.2 nm) was decreased, compared with that of the simple homopolymers blend (18.8 nm). From the current density-voltage characteristics, it was confirmed that the introduction of PSt into both P3HT and P(NDI2OD-T2) improves short-circuit current density (1.16 to 1.73 mA cm-2 and power-conversion efficiency (0.24% to 0.32%). Better performance is probably due to the uniformity of the phase separation, and the enhancement of charge mobility. [ABSTRACT FROM AUTHOR]

For regional weather forecasts and climate predictions, it is important to determine the optimal domain size, location, and top height. A wide model domain can be chosen to avoid noises from lateral boundaries but this can include the Tibetan Plateau and areas of northern Manchuria to the Kamchatka Peninsula in Northeast Asia. This study shows that topographic regions around the Tibetan Plateau and warm pool areas over the Manchuria in an extended model domain may have harmful effects on the accuracy of short‐ to medium‐range regional predictions on the downwind side in spring. The inaccuracy is related to model errors due to steep terrain regions in the Tibetan Plateau and cold bias in the lower stratosphere north of Manchuria. Well‐designed spectral nudging over the eastern flank of the Tibetan Plateau and the use of a higher model top are found to improve regional predictions for Northeast Asia in spring by effectively eliminating errors associated with steep topography and temperature biases in the upper troposphere and lower stratosphere, respectively. Our findings suggest possible ways to mitigate biases due to steep mountains and upper‐level processes in regional modeling. We discuss the role of our method in terms of uncertainties in regional weather forecasts and climate predictions. [ABSTRACT FROM AUTHOR]