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The beam optics in a nuclear microprobe is considered on the basis of quality criteria for focusing systems. In this consideration, empirical criteria with dominant chromatic or intrinsic spherical aberrations are used. In a more general criterion, where all aberrations can be taken into account, the maximum acceptance for a fixed beam spot size on the target is used. Another criterion, that is closest to an experiment, is based on the condition of the minimum spot size at a fixed beam current and takes into account the nonuniform distribution of ions in the phase volume. This review summarizes the studies of various types of quadrupole focusing systems and implies the need for further development of the nuclear microprobe by using aberration correctors and a compact system. The analysis of the influence of various aberrations on the resolution of a nuclear microprobe is conducted with special attention paid to the positioning aberrations in separated quadrupole probe-forming systems. It is demonstrated why integrated multiplets of quadrupole lenses are preferred in such systems. Methods to process experimental results for an adequate determination of the spot size on the target are considered.

The Bragg-edge neutron transmission imaging method can quantitatively visualize various types of crystalline microstructural information inside a bulk material over a large visualization field area. In this study, we investigated and improved both the experimental method and the data analysis method for the evaluation of crystalline phase volume fraction in steel composed of ferrite/martensite and austenite. For wavelength-resolved neutron transmission imaging experiments, we confirmed that accurate measurement of neutron transmission intensities was crucial. Therefore, the background neutrons scattered from a sample must be reduced. Simultaneously, we confirmed that a neutron wavelength resolution of approximately 1% was required. For the data analysis of the measured Bragg-edge neutron transmission spectrum, we used double March-Dollase orientation distribution functions for each crystalline phase to achieve effective spectrum correction of the crystallographic texture effect. As a result, this data analysis method allows improved evaluation of the crystalline phase volume fraction, compared with the use of a single March-Dollase function for each phase.

Al–Cr–Fe–Ni dual-phase high entropy alloys (HEAs) were prepared by arc melting, and the microstructure and wear behavior of HEAs were investigated. The results show that HEAs were consisted by face-centered cubic (FCC) phase and body-centered cubic (BCC) phase, which is consistent with the design. As the BCC phase volume fraction increases, the hardness increases from 183 HV (X-10) to 433 HV (X-90), since that the hardness of BCC phase is higher compared with the FCC phase. The average friction coefficient decreases from 0.409 to 0.111 and the wear depth of alloys decrease from 7.629 to 0.973 μm, which inadicate that the wear resistance of Al–Cr–Fe–Ni dual-phase HEAs are improved with the increase in BCC phase volume fraction. The volume fraction of BCC phase is the main factor affecting the wear behavior of alloys.

The article is devoted to problem of revision of the borders of the range (the phase volume) and adequacy of the perception of the world in speaker long disheveled locks of universe-social evolution of the man. It is shown that in man’s perception volume is conditioned by the physiological organization as well as by its place in the cosmos and the Earth biosphere. The accent is made on discovery determinant conditioning given range of the perception and facility of the expression available perception to information. It is revealed that the modeling of reality becomes more abstract and clear, but less concrete, adequate to the «ultimate reality» with its blurred forms.

The effect a limited cubic volume has on the critical temperature of ordering corresponding to the regular structure of a binary А0.5В0.5 system is considered. A molecular theory based on the lattice gas model, which is traditionally used to describe the ordered state of alloy components and adsorbates, is applied. It is assumed there is an external field near the cube boundary, changing the distribution of system components relative to the one in the phase volume and making the entire system heterogeneous. The dependence is obtained for a drop in the critical temperature of ordering when the cube side shrinks and the contribution from near-border areas of the domain to the entire heterogeneous system grows. The role of domain walls in related situations (magnetics and ferroelectrics) is discussed.

At present work proton-proton collision at high energies has been considered in patron model. Differential section of collision unpolarized and polarized protons has been determined.

We discuss the Hamiltonian model of an oscillator lattice with local coupling. The Hamiltonian model describes localized spatial modes of nonlinear the Schrodinger equation with periodic tilted potential. The Hamiltonian system manifests reversibility of the Topaj–Pikovsky phase oscillator lattice. Furthermore, the Hamiltonian system has invariant manifolds with asymptotic dynamics exactly equivalent to the Topaj–Pikovsky model. We examine the stability of trajectories belonging to invariant manifolds by means of numerical evaluation of Lyapunov exponents. We show that there is no contradiction between asymptotic dynamics on invariant manifolds and conservation of phase volume of the Hamiltonian system. We demonstrate the complexity of dynamics with results of numerical simulations.

A novel solid-phase microextraction Arrow was used to separate volatile organic compounds from soy sauce, and the results were verified by using gas chromatography with mass spectrometry. Solid-phase microextraction Arrow was optimized in terms of three extraction conditions: type of fiber used (polydimethylsiloxane, polyacrylate, carbon wide range/polydimethylsiloxane, and divinylbenzene/polydimethylsiloxane), extraction temperature (40, 50, and 60°C), and extraction time (10, 30, and 60 min). The optimal solid-phase microextraction Arrow conditions were as follows: type of fiber = polyacrylate, extraction time = 60 min, and extraction temperature = 50°C. Under the optimized conditions, the solid-phase microextraction Arrow was compared with conventional solid-phase microextraction to determine extraction yields. The solid-phase microextraction Arrow yielded 6-42-fold higher levels than in solid-phase microextraction for all 21 volatile organic compounds detected in soy sauce due to the larger sorption phase volume. The findings of this study can provide practical guidelines for solid-phase microextraction Arrow applications in food matrixes by providing analytical methods for volatile organic compounds.

Phase-field methods based on the Cahn–Hilliard (CH) equation coupled to the incompressible Navier–Stokes equation are becoming increasingly popular for interface resolving numerical simulations of two-phase flows of immiscible fluids. One major limitation of this approach, however, is that the volume of each phase is not inherently preserved. This is associated with the phase-discriminating order parameter, which in the course of the simulation remains in general not within its initial physical bounds. This shortcoming relates to the fact that the CH equation with standard Ginzburg–Landau chemical potential has no volume-preserving stationary solution for interfaces with uniform (non-zero) curvature. In this paper, a curvature-dependent chemical potential is proposed which allows for bounded stationary solutions of the CH equation for drops/bubbles exhibiting uniform curvature. Numerical solutions of the coupled Cahn–Hilliard Navier–Stokes equations show that the proposed chemical potential significantly improves boundedness and phase volume conservation over the standard one.

In commercial Al–Fe–Si foil stock alloys, mechanical properties such as strength and ductility are influenced by the materials microchemistry. This study covers the general relation of microchemistry and the potential final softening behavior of aluminum foil, as described in the literature. In this paper, the focus lies on the evolution of solute content and microchemistry through different experimental homogenization practices for two 8xxx alloys with varying Fe and Si contents. The solute level, dispersoid phase volume fraction, and phase morphology of precipitated particles are investigated. The experimental results show a major temperature dependency of the solute content during homogenization.

It is demonstrated that various combinations of models describing the adsorbed phase volume and the actual amount adsorbed (AAA) can be used to describe the experimental Gibbsian surface excess isotherm data for adsorption of a pure gas. Thus, the resulting AAA isotherm and the other adsorptive properties estimated by this approach can be ambiguous and artificial.

We suggest a methodology of assessing cyclic loading–induced damage in austenitic steel by combining the ultrasonic and magnetic monitoring. Cyclic loading increases the martensitic phase volume, thus enhancing the plastic deformation–and resulting damage–in the austenitic phase having lower strength and stiffness. The damage in the austenitic phase can be detected through wavespeeds changes. The latter, however, are small thus requiring high accuracy of wavespeeds measurements. These requirements are satisfied by focusing on ratios of the longitudinal and shear wavespeeds (that do not depend on imprecisely known parameters such as sheet thickness). In order to separate changes due to damage from the ones due to growth of the martensitic phase, we combine the acoustics- and magnetic data. Preliminary results on comparison with available experimental data are encouraging.

Bioaccessibility-based extraction tools, such as single-point Tenax extractions (SPTEs), provide cost-effective and accurate estimates of bioaccumulation and toxicity of hydrophobic organic contaminants during environmental sampling. Use of SPTEs as a screening tool in risk assessment is hindered by the requirement for normalization of extractable concentrations for organic carbon (OC). Normalizing SPTE concentrations for the volume of Tenax used during the extraction could improve the applicability of this methodology by removing the system dependence when applying SPTE concentrations to estimates of bioaccumulation. The objective of this study was to examine the utility of Tenax phase volume normalization in place of OC normalization when using SPTEs to estimate bioaccumulation. No significant differences were observed between the slope of regression lines generated between SPTE concentrations normalized for either Tenax phase volume or OC (p = 0.410), but slight improvement of the regression was noted when using phase volume normalization (R2 = 0.829) compared to OC normalization (R2 = 0.740). Replacing OC normalization with phase volume normalization in use of SPTEs more accurately represents the partition of the chemical to the Tenax during the SPTE, improves estimates of bioaccumulation, and expands the use of SPTEs as a rapid assessment tool for determining bioaccumulation during screening of contaminated environments.

We measure by experiment and particle-based simulation the rheology of concentrated, non-Brownian droplet emulsions functionalized with surface-bound single-stranded (ss), ``sticky,'' DNA. In the absence of ssDNA, the emulsion viscosity increases with the dispersed phase volume fraction $\ensuremath{\phi}$, before passing through a liquid-solid transition at a critical ${\ensuremath{\phi}}_{c}$ related to random close packing. Introducing ssDNA leads to a liquid-solid transition at $\ensuremath{\phi}l{\ensuremath{\phi}}_{c}$, the onset being set by the droplet valency $N$ and the ssDNA concentration (or simulated binding strength $\ensuremath{\epsilon}$). Using insight from simulation, we identify three key behaviors: (i) jammed suspensions ($\ensuremath{\phi}g{\ensuremath{\phi}}_{c}\ensuremath{\approx}0.64$) show weak effects of functionalization, with elastic rheology instead governed by droplet stiffness; (ii) suspensions with $\ensuremath{\phi}l{\ensuremath{\phi}}_{c}$ and $N=1$, 2 always exhibit viscous rheology, regardless of functionalization; and (iii) for $\ensuremath{\phi}l{\ensuremath{\phi}}_{c}$ and $Ng3$, functionalization leads to a controllable viscous-elastic transition. We present state diagrams showing the range of rheological tuning attainable by these means.

Headspace sorptive extraction technique using silicone based sorptive media coated stir bars is used for the first time here to extract, identify, and quantify heavy volatile organic compounds present in Escherichia coli culture headspace. Detection of infection presence is largely accomplished in laboratories through physical sampling and subsequent growth of cultures for biochemical testing. The use of volatile biomarkers released from pathogens as indicators for pathogenic presence can vastly reduce the time needed whilst improving the success rates for infection detection. To validate this, by using a contactless headspace sorptive extraction technique, the volatile compounds released from E. coli, grown in vitro, have been extracted and identified. Two different sorptive media for extracting these headspace volatiles were compared in this study and the identified volatiles were quantified. The large phase volume and wider retention of this sorptive technique compared to traditional sampling approach enabled preconcentration and collection of wider range of volatiles towards developing an extensive database of such heavy volatiles associated with E. coli. This supplements the existing data of potential bacterial markers and use of internal standards in these tests allows semi-quantitative estimation of these compounds towards the development and optimization of novel pathogen sensing devices.

The isosteric heat of adsorption strongly associates with the energetics of the adsorption processes. Being a direct function of the uptake amount, accurate modelling of the isosteric heat of adsorption is crucial in the design and development of adsorption systems. The isosteric heat of adsorption is often calculated using the Clausius-Clayperon equation with the perfect gas assumption and negligible adsorbed phase volume. We present a thermodynamic model of the isosteric heat of adsorption that addresses the non-ideal behaviour and the variation in the adsorbed phase density. The model is first validated using experimental data in comparison with the available models in the literature that invoke the ideal gas assumption with negligible adsorbed phase volume. Using these models, the isosteric heat for adsorption processes is examined from partial vacuum to high pressure as well as adsorption temperatures above the critical point. The impact of the prediction by each model on the system performance is then assessed in terms of the theoretical COP. For the realistic evaluation of system COP, an improved equilibrium cycle model is developed and the system performance is investigated using various models for the isosteric heat of adsorption. For adsorption at partial vacuum conditions, the COP values predicted by the ideal model are up to 1.8% higher when compared to the calculations using the present model. For high-pressure adsorption below the critical temperature, for example, Maxsorb III + R134a pair, the present model predicts 13% lower COP than the models available in the literature. The variation in the adsorbed phase density addressed in the present model leads to a higher value of isosteric heat (3.8%–8.6%) for adsorption above the critical temperature.

A systematic investigation of the effect made by the type of an apolar solvent on the properties of multiphase multicomponent structurally heterogeneous molecular–micellar nonequilibrium systems with the gradient of physicochemical properties along the normal to the phase boundary was carried out as concerns developing protective compositions. The theory of moisture transfer to the steel surface through hydrophobic films of compositions containing surface active agents and an apolar solvent basis was explored.

The complex chemical composition of coal slag separated out different types and shapes of crystals during the cooling process. The morphology of the crystal in the molten slag influenced the viscosity of the coal slag. The aim of this paper was to obtain the viscosity model of crystalline slag using a new calculation method. The model of the suspension viscosity obtained by the previous study was used to predict the viscosity of molten slag. The correction factor (β) was introduced in the model of the suspension viscosity. The solid phase volume fraction (φ) in the molten slag was calculated by FactSage. The liquid phase viscosity (η0) was fitted by the viscosities of molten slag in high temperature section. Ten kinds of crystalline slags were applied in this study to prove the accuracy of the modified viscosity model. The viscosity of molten slag predicted by the model (CSM) agreed with experiment data.

This study provides a general framework for the creation of three-dimensional microstructures for anisotropic two-phase materials with complex morphologies. The ability to create synthetic microstructures that are statistically representative of real materials is dependent on the ability of the generation algorithm to meet the assigned statistics. Hence, the fidelity of the synthetic microstructure depends on the efficiency of the generation process. The generated microstructures were statistically evaluated with respect to the target distribution for grain size, shape, orientation and phase volume fraction. This serves a dual purpose of validation of the packing algorithm and quantification of the 3D microstructures.

An alternative to the conventional ‘pore filling model’ for describing Gibbsian surface excess (GSE) isotherm from a liquid mixture on a porous adsorbent is proposed where the adsorbed phase volume is treated as a variable. The new model is tested using GSE isotherm data on various micro and mesoporous adsorbents. The adsorbed phase volume is found to be system specific but always less than the adsorbent pore volume, irrespective of the pore size.

Phase separation of biphasic solvent during CO2 absorption was investigated. Tested amine components were selected according to the molecular structure. Phase separation experiments shows the biphasic solvents comprised of polyamine and tertiary alkanolamine, such as DETA/DEEA and TMPDA/DEEA, may be suitable for the biphasic system due to easy phase separation. The CO2 absorption capacity of those biphasic solvents with different amine concentration was compared. The mixed amine solution of 3 M DETA and 2.5 M DEEA was the most potential blend in this screening study. CO2 absorption capacity of this biphasic solvent at 313K and 15 kPa CO2 partial pressure was 201 gCO2/kg and CO2-rich phase volume fraction was 80%. Liquid solutions from the upper and lower phases were analyzed individually. The upper phase was mainly DEEA with very low CO2 loading, the lower phase was composed of DETA, DEEA and water with very high CO2 loading. The CO2 and amine distribution between the upper and lower phases were measured during CO2 absorption.

Tiny water droplets in oil emulsions are commonly encountered in the petroleum industry. The high viscosity of the oil hampers the physical separation of the water droplets from the oil.[1] Phase inversion could be a potential workaround for this problem by making water, a much less viscous phase, the continuous medium. In the present work, we focused on triggering phase inversion of a solid-stabilized emulsion. We induced a catastrophic phase inversion by the continuous addition of a dispersed phase. The evolution of droplet morphology during the phase inversion process was observed and was measured in-line using a particle vision microscope, which proved to be a powerful tool for monitoring this rapid, unstable process. A linear relationship between the droplet size and the dispersed phase volume fraction before the phase inversion was observed, indicating that a higher dispersed phase volume fraction was needed for the phase inversion to occur with higher particle concentrations. The phase inversion conditions were applied in a regime where the particles were insufficient to fully cover the interface. Our findings indicated that the number of particles per surface area appears to be a crucial parameter in triggering phase inversion, regardless of the particle concentration. The phase inversion mechanism of our solid-stabilized emulsion can be explained by the relationship between the initial particle coverage of the interface and the coalescence rate of the system.

The spatially dependent phase distribution of focused few-cycle pulses, i.e., the focal phase, is much more complex than the well-known Gouy phase of monochromatic beams. As the focal phase is imprinted on the carrier-envelope phase (CEP), for accurate modeling and interpretation of CEP-dependent few-cycle laser-matter interactions, both the coupled spatially dependent phase and intensity distributions must be taken into account. In this Letter, we demonstrate the significance of the focal phase effect via comparison of measurements and simulations of CEP-dependent photoelectron spectra. Moreover, we demonstrate the impact of this effect on few-cycle light-matter interactions as a function of their nonlinear intensity dependence to answer the general question: if, when, and how much should one be concerned about the focal phase?

The method of obtaining the volume distribution of phases in structural materials is considered. The technique is based on the layer-by-layer grinding of metallographic samples with photo fixation of microstructure images and the subsequent computer processing of these images. An example of using the developed methodology to study the features of the volumetric distribution of graphite inclusions in high-strength cast irons is presented. The classification of graphite inclusions depending on the shape, size and distribution features is given. The study of the features of the distribution of graphite inclusions led to the conclusion about the patterns and mechanisms of formation graphite phase in cast iron.

Reduced-activation ferritic-martensitic (RAFM) steels are potential candidates for structural applications in future nuclear fusion power plants. A Ta-containing Fe-based commercial thermodynamic database was employed to calculate the phase volume fractions and their chemical compositions in Eurofer-97 RAFM steel. Results of the calculations were compared to those obtained from transmission electron microscopy, atom probe tomography and dilatometric experiments performed on short-term annealed samples. Despite minor discrepancies between experimental and calculation data, our findings suggest that the employed database is effective for calculating the phase equilibrium fields for Ta-containing steels.

Accurate estimation of the isosteric heat of adsorption is mandatory for a good modeling of adsorption processes. In this paper a thermodynamic formalism on adsorbed phase volume which is a function of adsorption pressure and temperature has been proposed for the precise estimation of the isosteric heat of adsorption. The estimated isosteric heat of adsorption using the new correlation has been compared with measured values of prudently selected several adsorbent-refrigerant pairs from open literature. Results showed that the proposed isosteric heat of adsorption correlation fits the experimentally measured values better than the Clausius-Clapeyron equation.

In this paper, the effects of asphalt-to-cement ratio (A/C) and water-to-cement ratio (W/C) on the elastic modulus E c of cement asphalt (CA) binder were studied through measuring the stress-strain curves and phase volume fractions of various CA binder specimens. The results illustrate that the CA binder with high asphalt content (A/C ⩾ 0.6) is a two-phase composite with complicated microstructure formed by both cement hydrates and asphalt agglomerates. The elastic modulus of CA binder decreases with the increase of A/C and W/C, especially A/C. A composite model that describes the CA binder in terms of the properties of asphalt and volume fractions of cement phases is suggested, and E c of CA binder can be predicted by this model according to A/C, W/C and properties of asphalt.

This paper studies the competition of fracture initiation in the ductile soft phase and in the comparatively brittle hard phase in the microstructure of a two-phase material. A simple microstructural model is used to predict macroscopic fracture initiation. The simplicity of the model ensures highly efficient computations, enabling a comprehensive study: a large range of hard phase volume fractions and yield stress ratios, for wide range of applied stress states. Each combination of these parameters is analyzed using a large set of (random) microstructures. It is observed that only one of the phases dominates macroscopic fracture initiation: at low stress triaxiality the soft phase is dominant, but above a critical triaxiality the hard phase takes over resulting in a strong decrease in ductility. This transition is strongly dependent on microstructural parameters. If the hard phase volume fraction is small, the fracture initiation is dominated by the soft phase even at high phase contrast. At higher hard phase volume fraction, the hard phase dominates already at low phase contrast. This simple model thereby reconciles experimental observations from the literature for a specific combination of parameters, which may have triggered contradictory statements in the past. A microscopic analysis reveals that the average phase distribution around fracture initiation sites is nearly the same for the two failure mechanisms. Along the tensile direction, regions of the hard phase are found directly next to the fracture initiation site. This ‘band’ of hard phase is intersected through the fracture initiation site by ‘bands’ of the soft phase aligned with shear. Clearly, the local mechanical incompatibility is dominant for the initiation of fracture, regardless whether fracture initiates in the soft or in the hard phase.

Several polyaniline, PANI, nanofibers, with controlled morphology and chiroptical properties were fabricated by using two developed unusual interfacial syntheses, UIS. Taking the l - and d -camphorsulfonic acid, CSA, as guiders, the first developed UIS is to prepare the bi-phase volumes in asymmetrical by setting the top phase volume/bottom phase volume, TPV/BPV, at 1/2 and 2/1 (vol%), respectively. The second developed UIS is to vary the diameter, Φ, of interfacial area at bigger, e.g. 71 mm, or smaller e.g. 52 mm, respectively. FESEM images showed that the reduction of the TPV and the increase of the interfacial area both would reduce the diameter of l / d -CSA doped PANI nanofibers. CD spectra showed that the reduction of the TPV and the increase of the interfacial area both would enhance the chiroptical properties of PANI nanofibers.

Because of phase separation characteristics, biphasic solvents are recognized as promising absorbents for CO2 capture with low regeneration heat consumption. However, limited CO2 loading in CO2-rich phase, associated with excessive CO2-rich phase volume, challenges the energy-saving regeneration potential of mixed-amine biphasic solvents. In this study, sulfolane was employed as a phase splitter to improve the phase separation properties of N,N-diethylenetriamine (DETA)-N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA) biphasic absorbent. By introducing the hydrophobic sulfolane, large CO2 capacity (increased from 3.56 to 6.48 mol/L) and low CO2-rich phase volume (decreased from 100% to 27.1%) were simultaneously achieved. Moreover, sulfolane acted as an absorption accelerator to increase the CO2 absorption rate in DETA-PMDETA-sulfolane solvent to 1.3 times the corresponding DETA-PMDETA solvent. Benefiting from the large CO2 capacity associated with favorable phase separation behavior, DETA-PMDETA-sulfolane has a minimized regeneration heat estimated at 1.86 GJ/t-CO2 at a lean CO2-loading of 0.55 mol/mol. This is 53.4% lower than the regeneration heat (3.99 GJ/t-CO2) using 5 M monoethanolamine solvent.

The structure formation influence on various macroscopic properties of fluid&ndash, fluid disperse systems is poorly investigated. The present work deals with the experimental study of the charge transfer in emulsions whose dispersed phase droplets are arranged into chainlike structures under the action of an external force field. The emulsions studied are the fluid system in which water droplets are dispersed in a hydrocarbon-based magnetic fluid. Under the effect of an external uniform magnetic field, anisotropic aggregates form from the emulsion dispersed phase drops. The low-frequency electrical conductivity of emulsions has been measured. It is demonstrated that the emulsions&rsquo, conductivity grows several times under the effect of magnetic field parallel to the measuring electrical field. The anisotropic character of the emulsion electrical conductivity in the presence of magnetic field has been demonstrated. It is revealed that the maximal response of conductivity on the magnetic field action takes place at the dispersed phase volume fraction of about 20%. The dynamics of the conductivity variation is analyzed in dependence on the magnetic field strength and the dispersed phase volume fraction. The obtained results may be of interest in the development of potential applications of disperse systems with magnetic-field-controllable properties.