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To solve the problem of high energy consumption in tailings pretreatment methods and explore a low energy consumption tailings activation method, alkaline hydrothermal activation pretreatment was carried out on part of sulfur tailings to enhance their activity and improve the mechanical properties of sulfur tailings-based geopolymers. The influences of activation temperature and activation time on alkaline hydrothermal activation effect have been studied. X-ray diffraction technology, Fourier transform infrared spectroscopy analysis, thermogravimetric analysis, nuclear magnetic resonance imaging analysis, and scanning electron microscopy test were used to characterize the performance of activated sulfur tailings and sulfur tailings-based geopolymers. The results show that when the sulfur tailings are activated at 200 °C for 2. 0 h, the prepared geopolymer obtains the highest 3 and 28 d compressive strength, which are 15. 5 and 22. 1 MPa, respectively. Alkaline hydrothermal activation can effectively destroy the crystalline phase in sulfur tailings, promote the release of active silica and aluminum. More hydration product gel is formed in the gel system to improve the pore structure of geopolymer, thus improving the compressive strength of sulfur tailings-based geopolymers. The above experimental results indicate that alkaline hydrothermal activation is a method that can effectively improve the activity of sulfur tailings. [ABSTRACT FROM AUTHOR]

Objective: Left ventricular dyssynchrony (LVD), the loss of coordinated contraction in the left ventricle, is an early sign of heart failure. LVD can be assessed using phase analysis techniques with gated single‐photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). This study aimed to investigate the impact of obesity on LVD through phase analysis. Methods: We retrospectively enrolled 152 obese patients and 80 age‐ and sex‐matched nonobese patients who showed normal myocardial perfusion and normal left ventricular ejection fraction (LVEF) on MPI. Phase standard deviation (PSD) and phase histogram bandwidth (PBW), as phase analysis parameters, were compared between patients with and without obesity. Results: Although PSD values were within the normal range (cut‐off value >23) for both groups, the PSD values of obese patients were higher than those of the nonobese (20.49 ± 8.66 vs. 14.81 ± 4.93; p < 0.05). PBW values of obese patients were statistically significantly higher than those of the nonobese (57.03 ± 23.17 vs. 41.40 ± 9.96; p < 0.05). The PBW values of obese patients exceeded the normal limits (cut‐off value >49). A weak positive correlation was observed between body mass index (BMI) and PBW values in obese patients (r = 0.181, p < 0.05). In patients of normal weight, no correlations were found between BMI and phase analysis parameters. Conclusion: LVD may develop in obese patients, even when myocardial perfusion and ejection fraction are preserved. The use of phase analysis with gated SPECT could be an additional finding improving the early detection of left ventricular dyssynchrony in obese patients. [ABSTRACT FROM AUTHOR]

This study investigates a new insulating refractory material based on rice husk ashes (RHA) for its application in the steel ingot casting process. The excellent insulating properties of this material may improve heat- and energy balance during ingot casting. A flame-sprayed alumina coating is applied to provide chemical inertness of the substrate material against the steel melt. The refractoriness, oxidation resistance, phase evolution and thermal expansion of four different grades of RHA materials and phase evolution and thermal expansion of flame-sprayed alumina coatings are studied. The refractoriness of the RHA materials increased with increasing silica content, showing sufficient refractoriness up to 1600 °C for SiO 2 > 94 wt%. Immersion tests with composite materials made from RHA substrate and a flame-sprayed alumina coating were successfully performed in a steel casting simulator. No deformation of the substrate material nor spalling of the flame-sprayed alumina coating was observed despite an immersion without preheating. [ABSTRACT FROM AUTHOR]

In this study, thermal analysis, composition phase, microstructure and physical and mechanical properties of Al2O3-based composites with titanium diboride and carbide reinforcements fabricated by in-situ spark plasma sintering method in Al-FeTiO3-B2O3-C alumino-thermic system have been investigated. This research explores the potential of utilizing Kahnuj (Iran-Kerman) ilmenite concentrate as a replacement for TiO2. The results of the thermal analysis demonstrate that aluminothermic reactions significantly intensify after the melting of aluminum and different compounds of iron aluminides (FeAl, Fe2Al5, and Fe3Al) and titanium diboride (TiB2) and carbide (TiC) are formed. Among the different systems of raw materials (Al-FeTiO3-C, Al-FeTiO3-B2O3, and Al + FeTiO3 + C + B2O3) only for system Al + FeTiO3 + B2O3, the intermetallic compounds of Fe3Al and Fe4Al13 are stable. For heat treatment with higher heating rates, the boron oxide participates more effectively in the aluminothermic reaction and the composition of titanium diboride is more noticeably formed. In the condition of 45 MPa in mechanical pressure, argon gas atmosphere with 3 bar pressure, heating rate of 100 °C/min, temperature of 1400 °C with dwelling time of 4 min (Optimum condition) for in-situ SPS processing of Al-FeTiO3-C system, the composite samples with the highest homogeneity in microstructure, density (4.10 g/cm3), hardness (281HV), bending strength (271.5 MPa) and highest wear resistance (Friction coefficient of 0.3 and 0.003 g of weight loss with 500 m of sliding distance) with optimal phase composition (Fe, Al2O3, TiC,...) was obtained. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) have drawn significant attention due to their unique design and superior mechanical properties. Comprising 5–35 at% of five or more elements with similar atomic radii, HEAs exhibit high configurational entropy, resulting in single-phase solid solutions rather than intermetallic compounds. Additive manufacturing (AM), particularly direct energy deposition (DED), is effective for producing HEAs due to its rapid cooling rates, which ensure uniform microstructures and minimize defects. These alloys typically form face-centered cubic (FCC) or body-centered cubic (BCC) structures, contributing to their exceptional strength, hardness, and mechanical performance across various temperatures. However, FCC-structured HEAs often have low yield strengths, posing a challenge for structural applications. In this study, a Ni-Co-Fe-Cr-Al-Ti HEA was manufactured using the DED method. This study proposes that the addition of aluminum and titanium creates a γ + γ′ phase structure within a multicomponent FCC-HEA matrix, enhancing the thermal stability and coarsening the resistance and strength. The γ′ phase with an ordered FCC structure significantly improves the mechanical properties. Analysis confirmed the presence of the γ + γ′ structure and demonstrated the alloy's high tensile strength and microhardness. This approach underscores the potential of AM techniques in advancing HEA production for high-performance applications. [ABSTRACT FROM AUTHOR]

This study aimed to assess the diagnostic efficacy of left ventricular synchrony (LVS) for detecting coronary artery disease (CAD). We explored whether the LVS index derived from phase analysis of D-SPECT provides superior diagnostic value compared to conventional perfusion analysis in identifying obstructive CAD. Patients with suspected or confirmed CAD underwent drug-stress/rest gated D-SPECT myocardial perfusion imaging (MPI) and coronary angiography (CAG). A 50% stenosis was set as the threshold for obstructive CAD. 110 participants were enrolled in this analysis. There were significant differences in phase standard deviation (PSD), phase histogram bandwidth (PHB) and entropy among the four groups. Patients without cardiac disease and those with mild-moderate stenosis exhibited no noticeable contraction asynchrony. However, LVS indices demonstrated a gradual increase with the progression of coronary stenosis when compared to NC (P < 0.001). Obstructive CAD was identified in 43 out of 110 participants (39%). Optimal cutoff values for diagnosing obstructive CAD during stress were determined as 7.6° for PSD, 24° for PHB, and 37% for entropy, respectively. Notably, PSD, PHB, and entropy indices exhibited higher sensitivity compared to MPI. The integration of the stress-induced LVS indices into routine MPI analysis resulted in a significantly greater area under the curve (AUC), leading to improved diagnostic performance and enhanced differential capacity. Stress-induced LVS indices increase with the severity of coronary artery stenosis by D-SPECT phase analysis. Further, the indices-derived phase analysis exhibits superior sensitivity and discriminatory ability compared to MPI in detecting obstructive CAD. [ABSTRACT FROM AUTHOR]

BACKGROUND: The beet webworm, Loxostege sticticalis, a worldwide pest of many crops, performs a seasonal migration, causing periodic outbreaks in Asia, Europe and North America. Although long‐distance migration is well documented in China, patterns of transboundary migration among China, Russia and Mongolia are largely unknown. We performed a phase analysis of L. sticticalis periodic outbreaks among three countries based on 30 years of historical population data, analyzed the wind systems during migration over boundary regions, and traced the migratory routes in a case study of outbreaks in 2008 by trajectory simulation. RESULTS: Highly synchronized outbreak years of L. sticticalis were observed between China and Mongolia, China and eastern Siberia, China and western Siberia, Mongolia and eastern Siberia, eastern Siberia and western Siberia from 1978 to 2008, indicating possible transboundary migration between these regions. Winds at 300–600 m altitude, where adult migration usually occurs, also showed a high probability of northwestern winds in Haila'er (China), Chita (Russia) and Choybalsan (Mongolia), favoring successful adult migration from these areas to northern and northeastern China. Back trajectory analysis further showed that the first‐generation adults that caused the severe outbreak of second‐generation larvae in 2008 originated from eastern Siberia, eastern Mongolia, and the boundary regions of China–Russia and China–Mongolia. CONCLUSION: Our findings demonstrated that the source of L. sticticalis outbreaks in northern China was closely related to the outbreaks in Siberia and Mongolia via long‐distance transboundary windborne migration. This information will help guide international monitoring and management strategies against this notorious pest. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The solar wind, representing one of the most impacting phenomena in the circum-terrestrial space, constitutes one of the several manifestations of the magnetic activity of the Sun. With the aim of shedding light on the scales beyond the rotational period of the Sun (i.e., Space Climate scales), this study investigates the phase relationship of a solar activity physical proxy, the Ca II K index, with solar wind properties measured near the Earth, over the whole space era (last five solar cycles). Using a powerful tool such as the Hilbert–Huang transform, we investigate the dependence of their phase coherence on the obtained time scale components. Phase coherence at the same time scales is found between all the components and is also preserved between adjacent components with time scales ≳ 2 yrs. Finally, given the availability of the intrinsic modes of oscillation, we explore how the relationship of Ca II K index with solar wind parameters depends on the time scale considered. According to our results, we hypothesize the presence of a bifurcation in the phase-space Ca II K index vs. solar wind speed (dynamic pressure), where the time scale seems to act as a bifurcation parameter. This concept may be pivotal for unraveling the complex interplay between solar activity and solar wind, bearing implications from the prediction and the interpretation point of view in Space Climate studies. [ABSTRACT FROM AUTHOR]

The present study aimed to observe and analyze the ocular movements induced by Coriolis stimulation (eccentric pitch while rotating: PWR) that induces Coriolis forces on the vestibular apparatus of healthy human individuals. A total of 31 healthy subjects participated in the study. Eccentric PWR was performed on 27 subjects, by pitching the participants' heads forward and backward at an angle of 30° each on an axis parallel and 7 cm below inter-aural axis, at a frequency of 0.5 Hz while on a chair rotating at a constant angular velocity of 97.2°/s on the earth-vertical axis. Ocular movements during stimulation were recorded using three-dimensional video-oculography. As a subsidiary analysis, 0.5 Hz head roll tilt was used as another stimulus that also induced torsional ocular movements. The forces induced on the vestibular apparatus, and phases of ocular torsion against the stimulus were calculated from the observed data. In the Coriolis stimulation during rightward yaw rotation, a rightward ocular torsion of 4.8° on average, was observed when the head pitched forward, and the direction of ocular torsion reversed when the head pitched backward. During leftward yaw rotation, these relationships were reversed with an average amplitude of 4.7° The phase of ocular torsion preceded that of Coriolis force by 0.2 s during rightward rotation and 0.14 s during leftward rotation. There were no significant differences in amplitude or phase between the directions of rotation. The phase lead of 0.5 Hz roll-tilt was significantly smaller than that of Coriolis stimulation (p < 0.01). Coriolis stimulation induced a specific pattern of ocular torsion, where its direction and phase suggested that the mechanism likely involved both the otolith and semicircular canals. Further studies may provide a clue to the magnitude of the otolith and semicircular canal contributions. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study discusses the anhydrous glass tube isothermal pyrolysis simulation for a crude oil, in order to explore the effects of effluent pressure on crude oil cracking. The results of gas chromatograph indicate that effluent pressure promotes the cracking of crude oil, increasing yields of C1–C5 saturates but inhibiting the generation of olefins. According to the calibration result of Soave–Redlich–Kwong equation of state, fluid phase transitions occur at very high effluent pressures, resulting in constant effluent pressure with no further increase in cracking efficiency and with invariant yields of pyrolysates. This study suggests that fluid phase transitions should be considered in petroleum exploration, which can help us to precisely determine the type of petroleum resources. [ABSTRACT FROM AUTHOR]

Strategic flood risk management of river catchments involves significant increases in the complexity both of the contents (e.g. the aims and measures) of a given strategy and also its social, spatial, and temporal scales. Conceptually, flood risk management research to date has underestimated the importance of time and temporality. This paper, which is based on ‘historical Institutionalism,’ introduces a temporal lens to focus on strategic flood risk management; it highlights issues of duration and timing as well as tempo and change in tempo with respect to the implementation of measures to reduce flood risk at catchment level. The application of a temporal lens is illustrated through empirical research into strategic flood risk management for the medium-sized Aist river catchment in Austria. The paper uses a longitudinal qualitative research design to analyze the changes in strategic flood risk management in the catchment. The analysis shows that strategy efforts in reaction to an extreme flood event in the catchment in August 2002 can be differentiated into three phases. Phase 1 is characterized by the design of ambitious catchment-wide management; Phase 2 by struggles to implement the strategy due to institutional conditions and protests by citizens; and Phase 3 by redesign of the initial strategic plan to make it less ambitious and by changes to the actor constellation supporting the plan. The present paper offers a process-oriented institutional explanation for this pattern of phases, and it highlights issues of timing and tempo. It concludes with general suggestions for enhancing the temporal dimension in flood risk management. [ABSTRACT FROM AUTHOR]

Phase analysis of silver in ores refers to the determination of the content of silver in various host minerals. Through experimental analysis, it is established that the main silver phases in the ore include 6 types: silver in smithsonite, silver in minerals bearing iron and manganese, native silver, silver sulfide, silver in iron oxides, and silver in silicates. Acetic acid is used to leach silver from smithsonite, sodium chloride - hydroxylamine hydrochloride is used to leach silver from minerals bearing iron and manganese, ferric nitrate solution is used to leach native silver, thiourea - sulfuric acid solution is used to leach silver sulfide, hydrochloric acid - stannous chloride is used to leach silver from iron oxides, and the remaining residue is measured for silver in silicates. The relative standard deviation of this method for determining each silver phase ranges from 0.22% to 5.36%. The sum of the silver content from each phase closely matches the total silver content measured, indicating that the phase separation method is correct and the test results are accurate. [ABSTRACT FROM AUTHOR]

Functional magnetic resonance imaging (fMRI) plays a crucial role in neuroimaging, enabling the exploration of brain activity through complex-valued signals. These signals, composed of magnitude and phase, offer a rich source of information for understanding brain functions. Traditional fMRI analyses have largely focused on magnitude information, often overlooking the potential insights offered by phase data. In this paper, we propose a novel fully Bayesian model designed for analyzing single-subject complex-valued fMRI (cv-fMRI) data. Our model, which we refer to as the CV-M&P model, is distinctive in its comprehensive utilization of both magnitude and phase information in fMRI signals, allowing for independent prediction of different types of activation maps. We incorporate Gaussian Markov random fields (GMRFs) to capture spatial correlations within the data, and employ image partitioning and parallel computation to enhance computational efficiency. Our model is rigorously tested through simulation studies, and then applied to a real dataset from a unilateral finger-tapping experiment. The results demonstrate the model's effectiveness in accurately identifying brain regions activated in response to specific tasks, distinguishing between magnitude and phase activation. • Most fMRI studies use real-valued, magnitude only data, ignoring information in the complex part. • Identifying changes in magnitude and phase allows for detection of meaningful neuronal activity that would be missed by studying magnitude alone. • We propose a fully Bayesian model for identifying magnitude and phase changes in task-based BOLD fMRI. • The model accounts for spatial association via sparse Gaussian Markov random fields and is computationally scalable via parcellation. • We demonstrate that the model is able to not only identify task-related changes in BOLD signal, but the type of change (magnitude, phase, or both). [ABSTRACT FROM AUTHOR]

This study proposes a new optical system with the potential for time-lapse observation of living cellular tissue beyond the diffraction limit through speckle interferometry to facilitate biological research. The spatial resolution of this optical system was investigated and improved upon. This study also experimentally verified a finding from an earlier simulation study that the new super-resolution technology could be realised by analysing the phase distribution related to the shape of the measured object, preserved in the light reflected from the object. Additionally, a method was presented to confirm the positions of microstructures, based on the extracted characteristics of the structure. [ABSTRACT FROM AUTHOR]

Abundant tuff mineral resources offer a promising solution to the shortage of fly ash (FA) and silica fume (SF) resources as emerging supplementary cementitious materials. However, a lack of clarity on its hydration mechanism has hindered its practical engineering application. In this study, high SiO2-content tuff powder (TP) was examined to assess the mechanical and workability performance of mortar specimens with varying particle sizes of the TP as complete replacements for FA or SF. Microscopic analysis techniques, including X-ray diffraction (XRD), differential thermal analysis (DTG), and energy-dispersive X-ray spectroscopy (EDS), were employed to elucidate the hydration mechanism of the TP and its feasibility as a substitute for SF or FA. Results indicated that TP primarily functions as nuclei and filler, promoting cement hydration, with smaller particle sizes amplifying the hydration ability and increasing Ca(OH)2 and C-S-H gel content. The specimens with TP (median particle size 7.58 μm) demonstrated 9.2% and 29.9% higher flexural and compressive strengths at 28 days, respectively, compared to the FA specimens of equal mass. However, fluidity decreased by 23.1% accordingly. Due to TP's smaller specific surface area compared to SF, the TP specimens exhibited higher fluidity but with decreased strength relative to the SF specimens. Overall, TP shows potential as a replacement for FA with additional measures to ensure workability. [ABSTRACT FROM AUTHOR]

To produce high crystalline and unified cuprite nano single crystals from copper sulfate pentahydrate a unique bi-polarized methanol-water mixture reduces surface energy and enhances capping efficiency. Exhaustive significance lattice parameters, crystal volume, peak profiling, lattice constant, percent of crystallinity and crystal strain were analyzed by the whole powder pattern fitting (WFPP) Rietveld refinement method. A red shift at 636.0 nm in UV spectrophotometry is associated with a high surface plasmon effect and the zeta potential of 89.0 mV confirms the excellent stability of the cuprite crystal. Crystallographic data, d-spacing 0.25188 nm, lattice parameters a = b = c = 3.78 Å, α = β = γ = 90° of cuprite single crystal was further established by the selected area electron diffraction (SAED) in TEM. Energy dispersive spectroscopy (EDS) reveals the formation of the 100.0 % unified cuprite single crystal.

3D electron diffraction (3D ED) has shown great potential in crystal structure determination in materials, small organic molecules, and macromolecules. In this work, an automated, low‐dose and low‐bias 3D ED protocol has been implemented to identify six phases from a multiple‐phase melt‐crystallisation product of an active pharmaceutical ingredient, griseofulvin (GSF). Batch data collection under low‐dose conditions using a widely available commercial software was combined with automated data analysis to collect and process over 230 datasets in three days. Accurate unit cell parameters obtained from 3D ED data allowed direct phase identification of GSF Forms III, I and the known GSF inclusion complex (IC) with polyethylene glycol (PEG) (GSF‐PEG IC‐I), as well as three minor phases, namely GSF Forms II, V and an elusive new phase, GSF‐PEG IC‐II. Their structures were then directly determined by 3D ED. Furthermore, we reveal how the stabilities of the two GSF‐PEG IC polymorphs are closely related to their crystal structures. These results demonstrate the power of automated 3D ED for accurate phase identification and direct structure determination of complex, beam‐sensitive crystallisation products, which is significant for drug development where solid form screening is crucial for the overall efficacy of the drug product. [ABSTRACT FROM AUTHOR]

Electroless nickel plating is widely used to improve the functional characteristics of the engineering parts produced by different manufacturing processes. In most of the cases, these plated surfaces require precision finishing to achieve the desired optical properties for mirror applications. It is difficult to get a high level of surface finish using conventional finishing techniques because of high forces and heat generation. It may result in degradation in the surface properties. In the present work, a compliant finishing tool is used to achieve a surface roughness at the nanoscale on the nickel-plated surface with stainless steel as substrate. The residual stress influences the optical properties of the finished surface. The x-ray diffraction is used to analyze the phase and residual stress on the substrate, as-plated, and ultra-precision finished surface. Microhardness and wear characteristics of these samples are also studied to understand the effect of surface finishing operation on nickel plating. The hardness of the as-plated surface is much higher than the substrate, and there is negligible effect of finishing process on the hardness. Both as-plated and finished surfaces show better wear resistance. [ABSTRACT FROM AUTHOR]

We are concerned with the existence of traveling waves for density‐dependent diffusion reaction nonlinear convection equations with small time delay. We first study the existence and uniqueness of smooth and sharp‐type traveling wavefront solution of the wave speed c ≥ c∗ for equation without time delay, where c∗ is the minimal wave speed. Meanwhile, we construct a variational principle for c∗ from which the upper bound of c∗ is determined, while the lower bound of c∗ is attained by using the phase plane analysis. Then, we obtain the existence of smooth traveling wavefront solution for equation with small time delay for c > c∗ by applying the perturbation method and implicit function theorem. [ABSTRACT FROM AUTHOR]

The purpose of this work was to carry out comparative studies of WC-Co-Cr coatings deposited using the high velocity oxy fuel (HVOF) method onto two types of substrate material: structural steel S235 and magnesium alloy AZ31. The influence of the substrate material type on the microstructure, phase composition, crystallite size, porosity, Vickers microhardness, instrumental hardness (HIT), Young's modulus (EIT), and fracture toughness was investigated. For both substrates, the deposited coatings deposited were characterized with fine-grained and compact microstructure. The X-ray diffraction (XRD) revealed presence of following phases: WC, W2C, Co0.9W0.1, and Co3W9C4. The WC phase was the most desirable and stable one with crystallites were below 100 nm. On the other hand, the size of the W2C crystallites was below 30 nm. The coatings obtained showed porosity values equal to 2.3 ± 0.4 vol% and 2.8 ± 0.7 vol% for AZ31 and S235, respectively. The average Vickers microhardness for both types of sample was appproximately 1200 HV0.3. The average HIT values for carbide particles and metallic matrix were around 29 GPa and 6.5 GPa, respectively. In the case of EIT, it was around 620 GPa and 190 GPa for WC and Co-Cr, respectively. The differences between coatings were negligible. The EIT value for both coatings was equal to 344 ± 11 GPa. The fracture toughness was around 4.5 MPa · m1/2 in both cases. The investigations revealed that it is possible to replace steel substrate material with a much lighter equivalent, in this case AZ31 alloy, without deterioration of the coating properties. [ABSTRACT FROM AUTHOR]

Coal-bearing metakaolin (CMK) is a highly active volcanic material. In this study, the compressive strength of CMK cement soil was tested, along with five CMK samples cured in different concentrations of Na2SO4 solution. The compressive strength of the CMK cement soil first increased and then decreased with increasing Na2SO4 concentrations. When the Na2SO4 solution concentration was 18 g/L, the compressive strength of the CMK cement soil reached its maximum value. Additionally, X-ray diffraction (XRD) analysis of the chemical reactions between the CMK cement soil and Na2SO4 solution and scanning electron microscopy (SEM) were used to analyze the phase composition and microstructure of the CMK cement soil, respectively. Thus, the pore distribution of the CMK cement soil could be calculated and classified from a 500x magnification SEM image using Image-ProPlus6.0 analysis software. This study explains the mechanism of curing CMK cement soil in a Na2SO4 solution based on its phase analysis, microstructure, and pore distribution. [ABSTRACT FROM AUTHOR]

With the evolution of sport, the level of athletes is increasing. To be able to win it is necessary to understand what factors influence performance in competition and training. Sports performance analysis has evolved in accordance with data collection in competition practice, with performance indicators related to actions connected to performance outcome.Introduction. We intend to verify the importance of task analysis in the performance analysis procedures. The review starts with task definition, then task analysis procedures and sports science application to finish with examples of performance analysis with task analysis. Material and Methods. Each task has one or more goals with actions to be carried out and with task, performer, and environment constraints that influence it. Task analysis is a methodology to have information about technique, productivity and safety that allows developing training programmes. Sports task analysis has a preparatory phase, a description (phase analysis), assessment, and an intervention. Performance analysis was based on biomechanical and notational analysis including performance indicators and afterwards reinforced with the ecological dynamics approach with an emphasis on the performer-environment relationship. Similarities between actions from different sports could be observed with performance analysis using task analysis (phase analysis with description of the segmental actions and mechanical principles).Results. Performance task analysis could support evidence-based training programmes with a replication of key features and performance indicators in dry-land training tasks. Future research should identify task constraints and performance indicators with technological devices and make performance analysis more coach friendly.Conclusions. [ABSTRACT FROM AUTHOR]

This paper analyzes the beneficial effects on phase detection arising from the motion of an ac-coupled Doppler radar. Indeed, although the presence of an ac coupling stage suppresses the dc offset after the receiver RF output, due to the coupling capacitor, a high-pass behavior is introduced; the presence of a high-pass behavior leads to signal distortion, particularly for low Doppler frequencies, which are typical in many biomedical or industrial applications. Since the target displacement is usually extracted from the phase history, this effect might, in turn, worsen the overall accuracy of the system. Moreover, if the target alternates stationary and moving time intervals, the phase detection step becomes challenging. Indeed, during the stationary time, the output of the RF front-end shows only noise fluctuations that, in turn, result in uncorrelated phases which might be confused with the real target displacement. This negative effect might be avoided by keeping the radar continuously moving, thus exploiting what is usually considered a state that is negative and worthy of attention. In this contribution, this effect is addressed from a different perspective, and ad hoc experimental case studies are shown to demonstrate the effectiveness of the proposed system. This task has been accomplished through theoretical analysis and related experimental activity. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) have drawn significant attention due to their unique design and superior mechanical properties. Comprising 5–35 at% of five or more elements with similar atomic radii, HEAs exhibit high configurational entropy, resulting in single-phase solid solutions rather than intermetallic compounds. Additive manufacturing (AM), particularly direct energy deposition (DED), is effective for producing HEAs due to its rapid cooling rates, which ensure uniform microstructures and minimize defects. These alloys typically form face-centered cubic (FCC) or body-centered cubic (BCC) structures, contributing to their exceptional strength, hardness, and mechanical performance across various temperatures. However, FCC-structured HEAs often have low yield strengths, posing a challenge for structural applications. In this study, a Ni-Co-Fe-Cr-Al-Ti HEA was manufactured using the DED method. This study proposes that the addition of aluminum and titanium creates a γ + γ′ phase structure within a multicomponent FCC-HEA matrix, enhancing the thermal stability and coarsening the resistance and strength. The γ′ phase with an ordered FCC structure significantly improves the mechanical properties. Analysis confirmed the presence of the γ + γ′ structure and demonstrated the alloy’s high tensile strength and microhardness. This approach underscores the potential of AM techniques in advancing HEA production for high-performance applications.

The angular distributions of the elastic and inelastic scattering of α-particles on 10B nuclei were measured at an energy of 29 MeV (with excitation of the 0.718 MeV (1+) state). The data obtained by us, together with the angular distributions of the elastic scattering measured earlier in a wide range of energies from 24 to 90 MeV, were described using an optical model, the coupled-channel method, and parameterized phase analysis. The optimal parameters of optical potentials were found, and a good description of the experimental data in the specified energy range of α-particles was achieved. By taking into account the contribution of the elastic transfer mechanism of the 6Li cluster, it was possible to correctly reproduce the rise of the cross section at the backward angles in the elastic channel. The value of the quadrupole deformation parameter was extracted from the analysis of inelastic scattering using the coupled-channel method. The geometric parameters of the interaction potentials were determined using parameterized phase analysis. The radii of the 10B nuclei in the high-energy region (30 MeV and above) obtained by PPA are in good agreement with the radii calculated in the framework of the optical model. [ABSTRACT FROM AUTHOR]

The sol-gel technique can be used to fabricate purified copper (II) oxide (CuO) and doped Fe nanoparticles. Synthesized nanostructures were examined using XRD, FTIR, UVvisible spectroscopy, SEM-EDX, and vibrating sample magnetometer to determine their crystalline nature, shape, surface area, and elemental composition. Under visible light illumination, photocatalytic evaluations of methylene blue (MB) dye degradation with binary metal oxides were conducted to evaluate the catalyst's recyclability. The photocatalytic degrading of the MB dye pollutant by CuO nanoparticles doped Fe has been shown in detail experiments under visible light irradiation. [ABSTRACT FROM AUTHOR]

Multilayer CrN/ZrN coatings deposited by the vacuum-arc method were subjected to thermal cycling in a furnace. The change in surface roughness of the coatings was studied using laser scanning confocal microscopy. Additional research was carried out using synchrotron radiation in asymmetric mode to detect the effect of thermal cycling on coating degradation. An analysis of the experimental data showed that the deposited coatings gradually degraded as the number of heating cycles increased. It should be noted that coatings obtained at substrate holder speeds of 5 and 8 rpm are more resistant to this type of impact than those obtained at speeds of 0.5 and 3.5 rpm. It is also noted that holding for 10 cycles has practically no effect on the phase state of the coatings. X-ray diffraction patterns showed the presence of β-Zr phase in the samples obtained at a substrate holder rotation speed of 5 and 8 rpm, which affected their thermal stability. However, after 40 cycles, the CoWO4 phase was detected in the coatings, which indicates the oxidation of the substrate and the loss of the protective functions of the coatings. [ABSTRACT FROM AUTHOR]

The characteristics of red pigments of the Gaya cultural circles, the ancient federation kingdom in the southern part of the Korean Peninsula, have been investigated using multiple analyses (SEM–EDS, XRD, Raman and Mössbauer spectroscopy). In results, reddish ochre- and pure hematite-based pigments were distinguished. In addition, as the redness of the pigment increased, the proportion of well crystalline and magnetically ordered α-Fe2O3 phase also increased, whereas the amorphous and superparamagnetic Fe2O3 phase were decreased. These results indicate that the ancient Gaya people produced various red pigments according to their use by thermal treatment of reddish ochre and high-purity iron compounds. [ABSTRACT FROM AUTHOR]

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Currently, new sorting technology of coal and gangue not merely focuses on the identification of coal and gangue, but also emphasizes the fine identification of coal. Therefore, this paper takes the main coal types, including one-third coking coal, gas coal, and gangue in Huainan coalfield as the research object, and proposes a method to identify coal types and gangue. The ADXRD patterns and EDXRD patterns of the samples were obtained through X-ray diffractometer and EDXRD test platform, respectively. The differences between the phase composition and the internal connection between the ADXRD pattern and EDXRD pattern of the samples were discussed, and the conversion of ADXRD pattern to EDXRD pattern of coal and gangue was simulated, the PSO-SVM identification model of coal types and gangue was established. The experimental results show that this method provides a new and effective technical way for coal types and gangue identification, which has important reference significance for fine identification of coal and gangue. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a mathematical model of the photoplethysmogram, which can be used to test methods that introduce the instantaneous phases of the modulating signals. The model must reproduce statistical and spectral characteristics of the real photoplethysmogram, and explicitly incorporate the instantaneous phases of the modulating signals, so they can be used as a reference during testing. Methods. Anacrotic and catacrotic phases of the photoplethysmogram pulse wave were modeled as a sum of two density distributions for the skew normal distribution. The modulating signals were introduced as harmonic functions taken from the experimental instantaneous phases of the VLF (0.015...0.04 Hz), LF (0.04...0.15 Hz) and HF (0.15...0.4 Hz) oscillations in the real photoplethysmogram. The spectral power in the VLF, LF, and HF frequency ranges was calculated to compare the model and experimental data. Results. The model qualitatively reproduces the shape of the experimental photoplethysmogram pulse wave and shows less than 1% error when simulating the spectral properties of the signal. Conclusion. The proposed mathematical model can be used to test the methods for introduction of the instantaneous phases of the modulating signals in photoplethysmogram time-series.

This study proposes a new optical system with the potential for time-lapse observation of living cellular tissue beyond the diffraction limit through speckle interferometry to facilitate biological research. The spatial resolution of this optical system was investigated and improved upon. This study also experimentally verified a finding from an earlier simulation study that the new super-resolution technology could be realised by analysing the phase distribution related to the shape of the measured object, preserved in the light reflected from the object. Additionally, a method was presented to confirm the positions of microstructures, based on the extracted characteristics of the structure.

The phase composition of several fragments of the ancient ceramic of the early medieval settlement of Asusay and burial ground Eleke Sazy in the modern Republic of Kazakhstan has been studied using neutron diffraction and Raman spectroscopy. The quartz, calcite, and feldspar minerals are dominant phases in the studied ceramic fragments. The fractions of those phases were obtained. The spatial arrangement of inner components inside volumes of fragments was determined using neutron tomography. The pores in the ceramic fragments were segmented, and the porosity for each sample was obtained. The phase composition and internal pores are discussed within the framework of the structural indicators of local clay sources and features of ancient pottery technologies.

In the wireless charging system, the power transmission follows the magnetic coupling relationship between the transmitting coil and receiving coil. When there are metal foreign objects between the transmitting coil and receiving coil, the eddy current effect or magnetic focusing effect of the foreign objects will affect the transmission performance and operational stability of the wireless charging system, and in severe cases, it can also endanger charging safety. In order to clarify the influence mechanism of metal foreign objects with different materials on the performance of wireless charging system and effectively analyze the influence law of foreign objects, an accurate modeling method of metal foreignobjects is urgently needed to improve the detection accuracy of metal foreign objects. Therefore, an equivalent modeling method of metal foreign objects field is proposed, taking into account the key factors of metal material, location, equivalent area and so on. By constructing the coupling equation of wireless charging system under the influence of metal foreign objects, the expression of phase difference between the transmitting coil current and receiving coil current before and after the introduction of foreign objects is obtained. On this basis, the equivalent coil model of ferromagnetic metal and non-ferromagnetic metal and its parameter configuration method are further proposed, which can accurately obtain the current phase difference under the condition of metal foreign objects intervention. Finally, the accuracy and effectiveness of the modeling method are verified by simulation and experiment. This method provides a new idea for the characteristic analysis and online detection of metal foreign objects introduced in wireless charging system.

This study extensively investigated characteristic non-metallic inclusions in oxidized and deoxidized 42CrMo4 steel after contact to MgO–C refractories, proposing possible formation and modification mechanisms of non-metallic inclusions. The structures and compositions of different inclusion species were analyzed, revealing various types: crystalline, amorphous, and complex inclusions containing both crystalline and amorphous phases. The latter always consisted of an amorphous Mn–Si–Al–O matrix containing various crystalline phases such as Al2O3, MnAl2O4 and/or MnTiO3. The formation of amorphous Mn–Si–Al–O inclusions was attributed to steel melt oxidation, while pure crystalline corundum inclusions resulted from both the steel melt oxidation and deoxidation. Alumina inclusions exhibited different shapes, likely because of variations in aluminum and oxygen supersaturation in the steel melt during their formation. Complex inclusions were suggested to form through precipitation on existing inclusions and mutual collision of pre-existing inclusions, facilitated by the non-wetting behavior of solid alumina inclusions in the steel melt.

Purpose: Phase analysis can assess left ventricular dyssynchrony. The independent prognostic value of phase variables over positron emission tomography myocardial perfusion imaging (PET-MPI) variables including myocardial flow reserve (MFR) has not been studied. The aim of this study was to explore the prognostic value of phase variables for predicting mortality over standard PET-MPI variables. Methods: Consecutive patients who underwent pharmacological stress-rest 82Rb PET study were enrolled. All PET-MPI variables including phase variables (phase entropy, phase bandwidth, and phase standard deviation) were automatically obtained by QPET software (Cedars-Sinai, Los Angeles, CA). Cox proportional hazard analyses were used to assess associations with all-cause mortality (ACM). Results: In a total of 3963 patients (median age 71 years; 57% male), 923 patients (23%) died during a median follow-up of 5 years. Annualized mortality rates increased with stress phase entropy, with a 4.6-fold difference between the lowest and highest decile groups of entropy (2.6 vs. 12.0%/year). Abnormal stress phase entropy (optimal cutoff value, 43.8%) stratified ACM risk in patients with normal and impaired MFR (both p < 0.001). Among three phase variables, only stress phase entropy was significantly associated with ACM after the adjustment of standard clinical and PET-MPI variables including MFR and stress-rest change of phase variables, whether modeled as binary variables (adjusted hazard ratio, 1.44 for abnormal entropy [> 43.8%]; 95%CI, 1.18–1.75; p < 0.001) or continuous variables (adjusted hazard ratio, 1.05 per 5% increase; 95%CI, 1.01–1.10; p = 0.030). The addition of stress phase entropy to the standard PET-MPI variables significantly improved the discriminatory power for ACM prediction (p < 0.001), but the other phase variables did not (p > 0.1). Conclusion: Stress phase entropy is independently and incrementally associated with ACM beyond standard PET-MPI variables including MFR. Phase entropy can be obtained automatically and included in clinical reporting of PET-MPI studies to improve patient risk prediction. [ABSTRACT FROM AUTHOR]

Measuring the deflection of bridges in service is crucial for monitoring their structural health conditions. Recently, the image measurement method has been developed to measure the bridge deflection, wherein the camera for taking images is installed at a distant place where the target bridge can be seen. In this study, we developed a simple but effective optical method to measure the out-of-plane displacement of a bridge, which could not be done before, from the images captured with a camera installed under the bridge. The proposed method converts the virtual in-plane displacement evaluated from the sampling moiré measurement into the out-of-plane displacement under the assumption that the target bridge and the reference point move in the in-plane direction as a rigid-body deformation, or the in-plane displacement is absent or negligible. In field experiments to measure the deflection of a viaduct during the passage of a high-speed train (Japanese Shinkansen) with a speed of 320 km/h, we successfully measured the bridge deflection less than 1 mm from images recorded with a camera installed under the bridge floor. When comparing the difference in deflections measured from the proposed method and a conventional Laser Doppler vibrometer, the average absolute difference was less than 0.05 mm. Our developed method is simple and cost-effective, making this technique very efficient in structural health monitoring of elevated railway or road bridges. [ABSTRACT FROM AUTHOR]

Background: To compare phase analysis with positron emission tomography (PA) and magnetic resonance feature tracking derived myocardial strain (FT) for left ventricular (LV) mechanical dyssynchrony using PETMR system in patients with ischemic heart disease. Methods and results: Patients who underwent rest-pharmacological stress 13N ammonia PETMR were enrolled. Histogram bandwidth (BW) and phase standard deviation (PSD) were compared to global longitudinal, long axis radial, short axis circumferential, and radial strain (GLS, GRS, SA Circ, and SA Rad) obtained from FT. LV dyssynchrony index (SDI) derived from PA and FT were compared. BW and PSD showed significant correlations with FT (a Pearson's coefficient r = 0.64, P <.0001, and r = 0.51, P <.0001 for SA Circ; r = 0.67, P <.0001, and r = 0.74, P <.0001 for GLS; r = − 0.60, P <.0001, r = − 0.61, P <.0001 for SA Rad; r = − 0.62, P <.0001, and r = − 0.68, P <.0001 for GRS, respectively). Bland-Altman plots for SDI showed a preferable agreement (95% limit of agreement − 0.12 to 0.075, − 0.20 to 0.098, − 0.38 to 0.077, and − 0.37 to 0.032; bias 0.0068 ± 0.056, 0.026 ± 0.068, 0.11 ± 0.088, and 0.13 ± 0.079 for SA Circ, SA Rad, GLS, and GRS, respectively). Conclusion: In simultaneous acquisition using PETMR, comparison of PET phase analysis and MR strain showed a good correlation. [ABSTRACT FROM AUTHOR]

The qualitative X-ray phase analysis of natural and artificial food sweeteners was applied to trace the authenticity of such food additives. The mineral composition of different sweeteners commonly added to foods was studied to estimate their mineral profiles and assess the risk related to the toxic elements intake caused by sweetener consumption. The concentration of twenty elements (Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr, Ti, V, and Zn) was measured using the inductively coupled plasma–optical emission spectroscopy (ICP-OES) method after the representative samples were wet-digested with a concentrated nitric acid and hydrogen peroxide mixture in a closed-vessel microwave-assisted system. Differences between the mineral compositions of the examined sweeteners were statistically evaluated and discussed. The relationships between the concentrations of the elements determined in the analyzed sweeteners were also investigated. The successful application of the X-ray powder diffraction method proved the identity of all investigated sweeteners; all the analyzed products contained the expected sweetening agent. The results of the quantification of all the elements in the examined sweeteners indicated that these products cannot be considered nutritionally dense. Hence, the presence of toxic elements like Cd, Cr, Ni, and Pb distinctly indicates the need to test such products to guarantee their quality and ensure consumer safety. [ABSTRACT FROM AUTHOR]

Si3N4/TiN ceramic composites have been prepared by hot pressing in a nitrogen atmosphere using fine Si3N4 and Ti powders and CaO–Al2O3 sintering aids and investigated. The results demonstrate that hot pressing was accompanied by titanium nitridation, yielding titanium nitride with the composition TiN0.9. Reaction between silicon nitride and the sintering aid led to the formation of a Ca-α-SiAlON with the composition Ca0.67(Si10Al2)(N15.3O0.7). In addition to the major phases, calcium aluminosilicate with the composition Ca3Al2Si3O12 was identified. Increasing the percentage of titanium nitride in the composites prepared at a temperature of 1650°C led to an increase in their density and Vickers microhardness: from 3.18 ± 0.03 to 4.33 ± 0.03 g/cm3 and from 17 ± 1.1 to 29.4 ± 0.9 GPa, respectively. [ABSTRACT FROM AUTHOR]