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Using the AC electric field to induce the orientation of nonlinear conductive fillers in composites is an effective solution for alleviating electric field distortion in power modules. However, the mechanism by which the electric field affects the filler dynamic characteristics and the composites' electrical properties remains unclear. In this paper, the correlation between the microscopic dynamic processes of fillers and the macroscopic current amplitude was analyzed. The results show that the current increases rapidly (0 ∼ 173 s) and then slowly (173 ∼ 869 s) at 600 V mm−1, influenced by the rotation and attraction processes of the fillers. This demonstrates that the orientation stops at about 869 s and the filler orientation state is a key factor in determining the dielectric properties. Secondly, the global orientation evaluation index D for the filler network was proposed, which can also derive the minimum time and energy loss required for preparation. Finally, the impact of different filler orientations on the composites' conductivity was investigated. In the low electric field stress region, with the average carrier jump distance decreasing from 150.23 to 109.71 nm as the D increases from −0.93 to −0.05. On this basis, materials with nonlinear conductivity gradient distribution can be easily prepared. Before optimization, the electric field stress of the power module at the triple point was 35.79 kV. This composite can reduce the value to 15.42 kV, a decrease of 56.9%, while maintaining good electric field uniformity. [ABSTRACT FROM AUTHOR]

The pressure-time relation in the shock flow field of a near-earth air blast is complex. The triple point (TP) path is the physical boundary between the free and non-free shock flow fields. Accurately predicting the TP path is the basis for studying the evolution law of the reflection flow field and the guarantee of effectively assessing the damage power of the warhead. Based on the assumption that the Mach stem center is on the projection point of the blast center on the ground, the TP path calculation method was constructed by the geometric relationship. The unknown coefficients were solved using the existing TP data and the least square method. The TP prediction model proposed was compared with the existing ones on the calibration, new numerical simulation TP, and the measured real blast datasets. The error of the new numerical simulation TP data is within ±15% of the real value. The results show that the TP path prediction model proposed performs better. Most of its prediction results are within ±20% of three datasets compared to other models for the working conditions with the scaled height of burst from 0.397 to 2.777 m/kg1/3 and the horizontal scaled distance within 10 m/kg1/3 in the conventional cylindrical TNT explosion with the length-diameter of 1 in the air. The reliability of the prediction model is verified. [ABSTRACT FROM AUTHOR]

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To elucidate the influence of curvature on the mechanism governing stable detonation waves, this study delves into the experimental and numerical exploration of gaseous detonations within an annular channel utilizing a 2H2/O2/3Ar mixture. The investigation encompasses both empirical observations of the cellular structure of the detonation wave through a soot-coated stainless-steel plate and numerical simulations employing advanced methodologies. To capture the intricacies of the detonation phenomenon, the second-order additive semi-implicit Runge–Kutta method and the fifth-order weighted essentially non-oscillatory (WENO) scheme are adeptly employed for discretizing the time and spatial derivatives, respectively. The underlying chemical reactions during detonation are meticulously modeled using a detailed reaction mechanism. The pressure and velocity contours unveiling a nuanced picture are extracted using a numerical analysis. The inner wall divergence effect emerges as a critical determinant, weakening the detonation strength and consequently yielding the larger cellular structures. Contrarily, the outer wall convergence effect significantly amplifies the strength yielding the smaller cellular structures. This intricate interplay causes the detonation velocity to increase progressively along the radial direction. Furthermore, near the inner wall the detonation wave manifests periodic phases of augmentation and attenuation, resulting in oscillations in both the velocity and the pressure. A granular scrutiny of the flow field finer attributes underscores the continuous regeneration and dissolution of triple points along the wave front. Notably, triple point regeneration predominantly occurs near the outer wall surface, while their dissipation is more proximate to the inner wall. In the context of the stable detonation wave, equilibrium between triple point regeneration and decay sustains a constant triple point count on the wave front. This pivotal equilibrium enables the self-sustaining propagation of detonation within the annular channel. [ABSTRACT FROM AUTHOR]

The article proposes an equation system that includes functions describing the properties of H2O at the saturation line (pressure, vapor density, liquid density, saturated vapor pressure derivative, heat of vaporization, etc.). Firstly, this system satisfies the requirements of the renormalization group theory. Secondly, the system is in consistency with the Yang–Yang hypothesis in the critical point neighborhood. For describing the saturated vapor density, the Clausius–Clapeyron equation is involved. In writing the equation system, complexes characterizing the saturation line mean diameter behavior were used. The equation system includes: a) the complexes, which are selected in accordance with the recommendations suggested by Wang et al. for asymmetrical systems, b) critical indices, which are calculated on the basis of the critical point scale theory methods. Using the equation system, numerical values of the water property indicators are obtained in the range from the triple point temperature to the critical temperature. The uncertainty of the above-mentioned values are in satisfactory agreement with the uncertainties: a) of the corresponding data on the properties calculated by Wagner and Pruss in the range from the triple point temperature to the critical temperature, b) of the known experimental data. Various models of the saturation line and elasticity curve are compared with each other. It is shown that the proposed equation system conveys the available experimental information on the equilibrium water properties with a smaller uncertainty than the known models do. Data on the mean diameter are calculated on the basis of the equation system in a wide interval of relative temperatures, including the critical point neighborhood. It is discussed a behavior of this diameter within the framework of some known models. [ABSTRACT FROM AUTHOR]

In this paper, by treating the cosmological constant as a thermodynamic pressure, we study the thermodynamics and phase transitions of the dyonic AdS black holes in Gauss-Bonnet-Scalar gravity, where the conformal scalar field is considered. In a more general extended phase space, we first verified the first law of black hole thermodynamics, and find that it is always true. Meanwhile, the corresponding Smarr relation is also obtained. Then, we found that this black hole exhibits interesting critical behaviors in six dimensions, i.e., two swallowtails can be observed simultaneously. Interestingly, in a specific parameter space, we observed the small/intermediate/large black hole phase transitions, with the triple point naturally appearing. Additionally, the small/large black hole phase transition, similar to the liquid/gas phase transition of the van der Waals fluids, can also be found in other parameter regions. Moreover, we note that the novel phase structure composed of two separate coexistence curves discovered in the dyonic AdS black holes in Einstein-Born-Infeld gravity disappears in Gauss-Bonnet-Scalar gravity. This suggests that this novel phase structure may be related to gravity theory, and importantly, it is generally observed that the triple point is a universal property of dyonic AdS black holes. On the other hand, we calculated the critical exponents near the critical points and found that they share the same values as in mean field theory. Finally, it is true that these results will provide some deep insights into the interesting thermodynamic properties of the dyonic AdS black holes in the background of conformal scalar fields. [ABSTRACT FROM AUTHOR]

On the example of industrial continuously-cast slabs 355 mm thick of two steels of different chemical compositions recommended for the production of thick heavy plates of quality categories S355ML according to EN 10025-4:2019 and S355NL according to EN 10025-3:2019 features of structure formation and their potential effect on low-temperature impact energy of a continuously cast slab are studied. Macro-and microstructural conditions are studied, the quantitative composition of structural components is calculated, the point of the ternary junction is determined, and values of low-temperature impact energy at 1/8, 1/4 and 1/2 of the slab thickness, 1/4 and 1/2 of the slab width are obtained, and the transition temperature for entirely brittle failure is established. Fractographic analysis is conducted, fracture structure is described, and non-metallic inclusions are identified. Individual examples of the possible inheritance of structural inhomogeneity from slab to thick sheet are illustrated. [ABSTRACT FROM AUTHOR]

In this paper, by treating the cosmological constant as a thermodynamic pressure, we study the thermodynamics and phase transitions of the dyonic AdS black holes in Gauss-Bonnet-Scalar gravity, where the conformal scalar field is considered. In a more general extended phase space, we first verified the first law of black hole thermodynamics, and find that it is always true. Meanwhile, the corresponding Smarr relation is also obtained. Then, we found that this black hole exhibits interesting critical behaviors in six dimensions, i.e., two swallowtails can be observed simultaneously. Interestingly, in a specific parameter space, we observed the small/intermediate/large black hole phase transitions, with the triple point naturally appearing. Additionally, the small/large black hole phase transition, similar to the liquid/gas phase transition of the van der Waals fluids, can also be found in other parameter regions. Moreover, we note that the novel phase structure composed of two separate coexistence curves discovered in the dyonic AdS black holes in Einstein-Born-Infeld gravity disappears in Gauss-Bonnet-Scalar gravity. This suggests that this novel phase structure may be related to gravity theory, and importantly, it is generally observed that the triple point is a universal property of dyonic AdS black holes. On the other hand, we calculated the critical exponents near the critical points and found that they share the same values as in mean field theory. Finally, it is true that these results will provide some deep insights into the interesting thermodynamic properties of the dyonic AdS black holes in the background of conformal scalar fields.

[Display omitted] • Giant (W rec > 9 j/cm3, and efficiency ∼80 %) was achieved at electric field <515 kV/cm. • Less than 6–4% variation upto 160 °C in W rec and efficiency was also recorded. • Giant P D = 252 MW/cm, C D = 2400 A/cm2, and ultra-fast t 0.9 = 26 ns was also achieved. • A high sensitivity factor (ξ = W rec /E = 179 J/(kV.m2)) was also observed. • Overall properties were achieved by the new concept of triple point (TCP) The development of high energy density in dielectric ceramics has become one of the most cutting-edge research topics for high pulse power technology applications owing to their high-power density and fast charge/discharge rates. However, dielectric ceramics often shows low energy density owing to the lack of high saturation polarization. Herein, we report a very interesting concept of tricritical/triple point (TCP) which is MPB between rhombohedral, Tetragonal, and Pseudo cubic is very beneficial for the excitement of more extra domains in relaxor ferroelectric ceramics. Since the ceramics are relaxors, domains can be reoriented easily when the field is removed, and very slim P - E loop could be expected to be obtained. Because of the second order (continuous phase transition), the relaxor ferroelectric ceramics maintained their (TCP) in a wide temperature range unlike normal ferroelectric ceramics making them promising for thermal stability. By constructing a triple point in a wide temperature range, high W rec > 9 j/cm3 with high efficiency of ∼80 %, and the sensitivity factor (ξ = W rec /E = 179 J/(kV.m2)) was achieved at a moderate electric field <515 kV/cm. Moreover, high-temperature stability up to 160 °C with less than 4–6 % variation in recoverable energy storage density, and working efficiency was also recorded. The reason for high W rec and their thermal stability in a wide temperature range owes to the (TCP) in a wide temperature range as confirmed by high-quality measurements such as HADAF, XRD, and high-temperature dielectric constant. This study not only focused on achieving high energy storage density but also provides a new strategy for the development of high recoverable energy density in a wide temperature range by utilizing the concept of (TCP). [ABSTRACT FROM AUTHOR]

Objective: Fronto-orbital advancement involves removal of the fronto-orbital bandeau. Visualization of the saw blade is lost as it passes through the fronto-orbital-sphenoid junction (FOSJ), placing the temporal lobe at risk of injury. We aim to provide a 3D analysis of the space surrounding this osteotomy to differentiate various types of craniosynostoses., Design: Retrospective cohort., Setting: Institutional., Patients: Thirty patients with isolated unicoronal synostosis, nonsyndromic bicoronal synostosis, metopic synostosis, Apert syndrome, Crouzon syndrome, and Muenke syndrome., Interventions: CT scans conducted between 2 months to 2 years of age were 3D reconstructed to compare craniometrics against normal controls., Main Outcome Measure(s): Craniometrics., Results: The mean bone thickness of the FOSJ at the level of the supraorbital rim was significantly small for the Apert, unicoronal and bicoronal groups. The mean vertical height of the middle cranial fossa from the lesser sphenoid wing was significantly greater in the unicoronal group. The mean vertical height of the tip of the temporal lobe from the lateral sphenoid ridge was greater in the unicoronal, isolated bicoronal, and Apert groups. The mean corneal protrusion beyond the lateral orbital rim was significantly greater in the Apert and unicoronal groups. The mean horizontal depth of the orbit was smallest in the Apert group. The mean vertical distance between the dacryon and the foramen cecum, and the mean volume of temporal lobe beneath the sphenoid shelf were the largest in the Apert group., Conclusions: Patients with Apert syndrome have the most unfavorable morphology of the anterior and middle cranial fossae., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.