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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]

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, one- and two-dimensional numerical simulations are carried out to study the effects of fuel concentration gradients (such as steep, intermediate and shallow) on the detonation wave behavior. The equivalent ratio range of detonation propagation, the quenching mechanism and the change of cell size are discussed in detail. The simulation results show, as the fuel concentration gradient increases, the detonation wavefront decays faster and decouples into a leading shock and a following flame at equivalence ratios of 0.68, 0.64 and 0.62, respectively. Moreover, there are two modes of the quenching mechanism. One occurs in the steep gradient that the detonation wave fails rapidly. The O2 in front of the detonation wave passes through the detonation wave and forms some unburned O2 pockets. The unburned pockets are affected by the marginal walls and reduce the heat release. The other occurs in the intermediate and shallow gradients that more triple points will survive in the flow field, which leads to a difference in the propagation speed of the detonation wavefront. This makes the detonation wavefront bent and deformed. The unburned O2 pockets are affected by the strong instability near the triple points and show different distribution characteristics compared with the steep gradient, which may be helpful to the detonation propagation. In addition, as the fuel concentration gradient increases, the triple points moving toward the wall gradually disappear while the triple points that move toward the center can continue to survive, which leads to the gradual increase in cell size and irregularity of the cell structure. [ABSTRACT FROM AUTHOR]

• The solubility of solid CO 2 in alkanes was experimentally investigated. • A novel experimental setup using the cooling curve method was designed, built and verified. • The temperature and pressure of the triple point of CO 2 were measured. • Activity coefficients were determined for the binary mixtures studied. • The Wilson equation was used for modelling the solubility of CO 2. The solid-liquid equilibrium (SLE) of binary systems containing carbon dioxide (R744) and alkanes propane (R290) and isobutane (R600a) was experimentally investigated. A novel experimental setup using the cooling curve method was designed, built and verified, enabling SLE measurements at temperatures down to 173 K. The temperature and pressure of the triple point of carbon dioxide (CO 2) were measured. The results for R744 and the binary mixture of carbon dioxide and propane were in agreement with the available literature data, demonstrating the accuracy of the experimental setup. Activity coefficients were determined for the binary mixtures studied. The Schröder and Wilson equations were used to calculate solubility over various temperatures and compositions. The Wilson model produced a very accurate correlation for the studied non-ideal binary mixtures, while the Schröder equation did not provide satisfactory results. Determined activity coefficients and SLE curves should be useful for the design of low-temperature refrigeration systems operating on carbon dioxide mixtures with low global warming potential. [ABSTRACT FROM AUTHOR]

Fix integers n > 1, d ? 4 and x > 0 such that (n + 1)(x-1) + take the general S such that S=r and let B denote the scheme-theoretic base locus of where 2S is the common union of the double point with S as their reduction. Then 2S is the union of the connected compwnents of B containing at least one point of S. We proivide this theorem proving that a general union ox x-1 double points and one triple pont has no higher cohomology in degree d. [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.

In the design of MV AC and DC spacers, the predominant factors are surface and interface conditions. Design is generally carried out on specifications and standards which are based on long-term experience and lab testing. However, the diffusion of power electronics with a trend to increase electric field, switching frequency, and rise time to achieve higher power density calls for an innovative, global approach to optimized insulation system design. A new methodology, based on field simulation, discharge modeling, and partial discharge inception measurements, called the three-leg approach, can form the basis to optimize insulation design for any type of supply voltage waveform. This paper focuses on the influence of the type of electrode on the inception and phenomenology of surface discharges and, as a consequence, on the interpretation of the results used for application of the three-leg approach. It is demonstrated that a typical electrode system used for insulating material testing can generate both gas and surface discharges at the triple point, when the electrodes have a smooth profile that is used to avoid corona or flashover. Hence, testing partial discharge may not provide a straightforward indication of the surface discharge inception and, thus, be partially misleading for insulation design. Another takeover is that such analysis must benefit from PD testing tools endowed with analytics able to provide automatic identification of the type of defect generating PD, i.e., internal, surface, and corona, since design and remedy actions can be taken, and adequate insulating materials developed, only knowing the type of source generating PD. Hence, testing partial discharge may not provide a straightforward indication of surface discharge inception and, thus, be partially misleading for insulation design. In addition to the importance of the three-leg approach to favor reliable and optimized design of insulation systems, there is a clear need to have a PD testing tool endowed with analytics. It should preferably be able to provide automatic identification of the type of defect generating PD, i.e., internal, surface, and corona. [ABSTRACT FROM AUTHOR]

To accurately predict the locations and trajectories of shock wave triple points in near-ground explosions, this study determined the propagation law of shock waves after the initiation of a detonator using a schlieren system. Moreover, it established a numerical simulation model using the Autodyn software and verified the accuracy of the model through a detonator explosion experiment. The propagation law of shock waves of TNT charges (1, 10 ​kg and 100 ​kg) at different heights of burst(0.5, 1.0, 1.5, 2.0 ​m,and 2.5 ​m) was studied through numerical simulations, and the triple point trajectories were fitted to an empirical formula. The results show that the maximum simulation error relative to the schlieren images of detonator explosions did not exceed 4 ​mm. As the scaled height of burst decreased, the positions of generated triple points were closer to the vertical projection of the explosion center and rose faster. As the scaled distance increased, the scaled height of triple points rose exponentially. The average error of triple point trajectories between the values predicted in this study and the experimental values was 4.1%, indicating that the accuracy of the fitted formula is acceptable. This study revealed the overpressure distribution law of shock waves and will provide a reference for shock wave overpressure measurements and explosion protection.

• SLE of five binary systems containing low GWP refrigerants were determined. • Measurements were carried out using two different experimental setups. • Almost all the binary systems showed clear eutectic points. • SLE of the binary systems usually agreed with the prediction of the Schröder equation. In this study, the solid–liquid equilibria of five binary systems containing refrigerants with low global warming potential, namely carbon dioxide (R744) + 1,1-difluoroethene (R1132a), R1132a + 2,3,3,3-tetrafluoropropene (R1234yf), R1132a + trans-1,3,3,3-tetrafluoropropene (R1234ze(E)), trifluoromethane (R23) + R1234yf, and R23 + R1234ze(E), was experimentally determined. Two experimental setups based on the cooling curve method were employed to measure the samples obtained from different sources. The results obtained using the two setups were in good agreement with the experimental uncertainty. In addition, the experimental data were compared with the values calculated using the Schröder equation, showing limited deviations. The accuracy of the experimental setups was tested by measuring the triple-point temperatures of the components of the studied binary systems, showing good agreement between the experimental data obtained for the pure refrigerants and the data available in the literature. [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]

One of the areas for improvement in ITS-90 is studied: the search for a fixed temperature point as an alternative to the triple point of mercury, e.g., the triple point of carbon dioxide. The need for this area of improvement arises from the signing in 2013 of the Minamata Convention on Mercury under the auspices of the UN and the avoidance of new measurement instrumentation based on mercury (liquid mercury thermometers, etc.). A cell for implementation of the triple point of carbon dioxide is designed. Methods for producing the triple point of carbon dioxide are introduced and the results of studies of its reproducibility are presented. These studies demonstrate that the use of the triple point of carbon dioxide offers promise as the fixed point for ITS-90 in place of the triple point of mercury, as well as the possibility of using it for calibration of both capsule and long-stem standard platinum resistance thermometers. [ABSTRACT FROM AUTHOR]

The non-uniqueness of the temperature scale realized on the standard platinum resistance thermometer (SPRT) calibrated at the triple point of sulfur hexafluoride (TPSF6) has been evaluated, given that SF6 is a potential candidate for substitution of the triple point of mercury (TPHg) which is indispensable point for the ITS-90. Three SPRTs calibrated at the TPSF6 were compared with a reference thermometer from 14 K to 250 K using a precise measurement system for capsule type thermometers. The uncertainty of the temperature scale due to propagation of the uncertainties for calibrating the SPRTs was also evaluated. The results showed that the non-uniqueness of the temperature scale of the SPRTs calibrated at the TPSF6 was almost equivalent to that of the current ITS-90. This indicates that the TPSF6 possesses the capability for realization of a modified ITS-90 which is equivalent to the current ITS-90.

A recent study reported the enhancement of thermoelectric response due to the presence of triple point phonons [Phys. Rev. Mater 2, 114204 (2018)]. Because the topological triple point phonons field is still at its early stage, it is necessary to search for realistic materials with ideal triple point phonons. In this work, we show that cubic Ca3I3P is an excellent material to host the ideal charge-two triple points at high-symmetry points Γ and H. Because the charge-two triple points have a topological charge of |C| = 2, two arc-shaped surface states emanating from the projections of each charge-two triple nodal point can be found in cubic Ca3I3P. It is hoped that the ideal charge-two triple point phonons and the clean phononic arc-shaped surface states in Ca3I3P can be experimentally confirmed shortly.

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Benefiting from the high breakdown voltage of the silicon carbide (SiC) material, the medium voltage SiC power module has made an unprecedented breakthrough, which is regarded as a promising route for the high voltage converter. However, partial discharge (PD) challenges the reliability and safety of the medium voltage SiC power module, which limits its massive applications in industrial fields. In this article, insightful models are proposed to reveal the mechanism of the electric-field-dominated PD in the medium voltage power module. Furthermore, it is found that the distorted electric field at the triple point of the power packaging is caused by the edge effect. Besides, the low-cost equipotential ring concept and structure are proposed to dramatically decrease the distorted electric field at the triple point. Additionally, the experiment platform with ultra-low interferences is presented to assess and localize the PD. With the aid of the proposed test bench, the PD principles in conditions of different ceramic thicknesses, electrode distances, and copper lengths of the copper plates of the DBC are measured. Comparative experiments ensure the feasibility and effectiveness of the proposed equipotential ring structure, which can significantly decrease the PD issue and promote the isolation level of the medium voltage SiC power module. [ABSTRACT FROM AUTHOR]

[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]

The nature of the phase transition has been studied in MnNi _1− _x Co _x Ge _0.97 Al _0.03 ( x = 0.20–0.50) through magnetization, differential scanning calorimetry and x-ray diffraction measurements; and the associated reversibility in the magnetocaloric effect has been examined. A small amount of Al substitution for Ge can lower the structural phase transition temperature, resulting in a coupled first-order magnetostructural transition (MST) from a ferromagnetic orthorhombic to a paramagnetic hexagonal phase in MnNi _1− _x Co _x Ge _0.97 Al _0.03 . Interestingly, a composition-dependent triple point (TP) has been detected in the studied system, where the first-order MST is split into an additional phase boundary at higher temperature with a second-order transition character. The critical-field-value of the field-induced MST decreases with increasing Co concentration and disappears at the TP ( x = 0.37) resembling most field-sensitive MST among the studied compositions. An increase of the hexagonal lattice parameter a _hex near the TP indicates a lattice softening associated with an enhancement of the vibrational amplitude in the Ni/Co site. The lattice softening leads to a larger field-induced structural entropy change (structural entropy change≫ magnetic entropy change, for this class of materials) with the application of a lower field, which results in a larger reversibility of the low-field entropy change (|Δ S _rev | = 6.9 J kg ^−1 K for Δ μ _0 H = 2 T) at the TP.

The interaction between an incident shock wave and a wavy end-wall in a three-dimensional geometry is numerically simulated by using a high-order finite-difference solver with a ghost-cell immersed boundary method. The aim is to discover the differences of the unsteady propagation characteristics of triple bifurcation points and transverse waves at different incident shock Mach numbers ( M 1) and wavy wall amplitudes ( A ww ). For a benchmark case with M 1 = 1.5 and A ww = 1 mm, the simulated results are in a good agreement with other studies, indicating the reliability of the current simulation technique. The numerical results at M 1 = 1.5 , 1.9, 2.5, and 3.5 show that the Mach numbers of the transverse shock waves issued from the triple bifurcation points decrease with time according to a power function. It indicates that the deformation of the shock wave attenuates with time and its flat shape is gradually recovered. The stronger the incident shock wave is, the faster the deformation decays. In the central region, a petal-like vortex structure is observed near the wavy wall and its advancing speed with periodic fluctuation correlates with the cycle of the transverse motion of the triple bifurcation point. With the increase of M 1 , the petal-like vortex gradually grows up in size, and a faster rate can be observed in the normal direction. By comparing the propagation characteristics of transverse waves at different wavy wall amplitudes, it is discovered that the cellular pattern becomes more diverse as the wall amplitude increases. This is due to the multiple collisions of the transverse waves on the wavy wall, which leads to the multi-modal waves system in the shocked gas. [ABSTRACT FROM AUTHOR]

The dominant narratives currently offering critique of the neoliberal university suggest a professional environment that is both uncaring and unhealthy. This paper adopts a Deleuzian gaze on the rhizomatic multiplicity of teaching to identify and reinterpret key lines of flight within this assemblage – identified as care, pedagogic health and salutogenesis. It is argued that the perspective described by the coexistence of these lines may develop a more positive ontology as a basis from which a university may be able to work towards a more productive state of healthy learning. The point at which the three lines of flight co-exist is hypothesised as a 'triple point'. [ABSTRACT FROM AUTHOR]

• Triple point temperatures of new refrigerants were determined. • Ten HFOs, two HCFOs, and CF 3 I were investigated. • Measurements were conducted using two different apparatuses. The triple point temperature of refrigerants is crucial because it serves as a reference for the lower limit of their use temperature in a refrigeration system. In this study, the triple point temperatures for recently proposed refrigerants with low global warming potential were experimentally determined. Ten hydro-fluoro-olefins, two hydro-chloro-fluoro-olefins, and trifluoroiodomethane were investigated. The triple point temperatures of the refrigerants were determined from the obtained cooling and heating curves. To improve measurement accuracy, measurements were conducted on samples obtained from different companies using two different measurement devices. The measured data were found to be in good agreement within the estimated measurement uncertainty. [ABSTRACT FROM AUTHOR]

The article describes the composition and metrological characteristics of the State Primary Standard of temperature unit – kelvin – in the range from 0.3 K to 273.16 K GET 35-2021. GET 35-2021 allows reproducing and disseminating the temperature unit in accordance with the definition of kelvin, accepted at the 26th General Conference on Weights and Measures (26th CGPM) in 2018. GET 35-2021 includes three installations of acoustic gas thermometry developed in 2012–2019, which are the primary means of measuring temperature in the ranges of 79–273.16 K, 4.2–80K, 268.16–273.16 K. Equipment for reproducing the reference points of the International Temperature Scale ITS-90 has been upgraded in order to improve the accuracy. Based on the studies performed, the uncertainty of reproducing the thermodynamic temperature and temperature according to ITS-90 has been calculated. [ABSTRACT FROM AUTHOR]

• Laminar, fully developed two-phase flow in an arbitrary cross-section tube. • Behavior of the velocity and shear stress investigated near the triple point. • Local treatment and solution obtained independent of the tube's cross section. • Mathematical tools used to obtain a simple analytical solution. In this study, we propose a simple approach for examining the local behavior of the velocity and shear stresses in the vicinity of a triple point (TP) in a two-phase flow. We assume a laminar steady, fully developed, stratified two-phase flow with any contact angle, α , independent of the shape of the tube's cross-section. The axial component of the fluid's velocity can be treated as a scalar function in two dimensions that obeys Poisson's equation, together with the no-slip condition on the boundary (tube walls) and appropriate conditions on the interface between the phases. In our opinion, the exact solutions described in previous studies (for the special case of a cylindrical tube) are complicated and difficult to follow. Moreover, the approximated interface presented in previous studies predicts a geometric contact angle (α g e o m e t r y) that might not coincide with the physical contact angle, α , which is located at the real interface's shape. The exact solutions numerically solve the global problem for a circular tube (i.e., they find the velocity and shear stresses) and analytically obtain results in the vicinity of the TP to solve the problem with the aid of the residue theorem. However, we begin in the vicinity of the TP and our entire analysis focuses within this domain. To simplify the calculations, three steps are suggested: 1) zooming in on the TP allows us to approximate the curved arcs of the walls and the interface as straight lines (the tangents of the arcs of the wall and the outward ray of the interface) 1 1 Intuitively, for a local observation up to first order in distance, a regular curve can be approximated as a straight line; i.e., an arc can be approximated to a cord. Up to second order, a curve can be approximated as a circle. For a formal proof that Laplace's equation for the region is bounded by the wall circle (radius R w a l l), the interface circle (radius R i), and our radius R defined in Fig 2.2, a possible option is to Möbius-transform the wall circle and the interface circle into straight lines concurrent in the angle α (so the other meeting points of these circles are mapped onto the point at infinity), and to obtain the Laplace solution, thereby proving that when R / (min (R w a l l , R i n t e r f a c e)) < < 1 , the deviation tends to zero. ; 2) attaching a polar coordinate system where the origin of this coordinate system is located at the TP; and 3) suppressing the local driving forces and expressing distant driving forces as a function on the boundary, thereby leaving the velocity as a harmonic function. The proposed method can be converted for electromagnetism near a junction of several dielectric materials. Furthermore, the electromagnetic parallel problem can be extended to three dimensions; i.e., a junction point of prisms with different dielectric constants. [ABSTRACT FROM AUTHOR]

We evaluated the non-uniqueness of the temperature scale of the standard platinum resistance thermometer (SPRT) calibrated at the tripe point of sulfur hexafluoride (TPSF6), which is one of the candidates for the substitute of the triple point of mercury (TPHg). Three SPRTs calibrated at the TPSF6 were compared with a reference thermometer from 14 K to 250 K by using a precise comparison system for capsule type of thermometers. The uncertainty of the temperature scales from propagation of the uncertainties for calibrating SPRT was also evaluated. The result shows that the non-uniqueness of the temperature scale of the SPRT calibrated at the TPSF6 was almost equivalent to that of the ITS-90. This means that the triple point of TPSF6 possessed a capability for realization of the temperature scale which was equivalent to the ITS-90.

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.

In 1897 Ostwald formulated his step rule for formation of the most stable crystal state for a system with crystal polymorphism. The rule describes the irreversible way a system converts to the crystal with lowest free energy. But in fact the irreversible way a supercooled gas below the triple point temperature Ttr.p. crystallizes via a liquid droplet is an example of Ostwald's step rule. The homogeneous nucleation in the supersaturated gas is not to a crystal, but to a liquid-like critical nucleus. We have for the first time performed constant energy (NVE) Molecular Dynamics (MD) of homogeneous nucleation without the use of a thermostat. The simulations of homogeneous nucleation in a Lennard-Jones system from supersaturated vapor at temperatures below Ttr.p. reveal that the nucleation to a liquid-like critical nucleus is initiated by a small cold cluster [S. Toxvaerd, J. Chem. Phys. 143, 154705 (2015)]. The release of latent heat at the subsequent droplet growth increases the temperature in the liquid-like droplet, which for not deep supercooling and/or low supersaturation, can exceed Ttr.p.. The temperature of the liquid-like droplet increases less for a low supersaturation and remains below Ttr.p., but without a crystallization of the droplet for long times. The dissipation of the latent heat into the surrounding gas is affected by a traditional MD thermostat, with the consequence that droplet growth is different for (NVE) MD and constant temperature (NVT) MD. [ABSTRACT FROM AUTHOR]

The process of bubble nucleation in a Lennard-Jones (LJ) liquid is studied by molecular dynamics (MD) simulation. The bubble nucleation rate J is determined by the mean life-time method at temperatures above that of the triple point in the region of negative pressures. The results of simulation are compared with classical nucleation theory (CNT) and modified classical nucleation theory (MCNT), in which the work of formation of a critical bubble is determined in the framework of the van der Waals-Cahn-Hilliard gradient theory (GT). It has been found that the values of J obtained in MD simulation systematically exceed the data of CNT, and this excess in the nucleation rate reaches 8-10 orders of magnitude close to the triple point temperature. The results of MCNT are in satisfactory agreement with the data of MD simulation. To describe the properties of vapor-phase nuclei in the framework of GT, an equation of state has been built up which describes stable, metastable and labile regions of LJ fluids. The surface tension of critical bubbles γ has been found from CNT and data of MD simulation as a function of the radius of curvature of the surface of tension R* The dependence γ(R*) has also been calculated from GT. The Tolman length has been determined, which is negative and in modulus equal to ≈(0.1 - 0.2)σ. The paper discusses the applicability of the Tolman formula to the description of the properties of critical nuclei in nucleation. [ABSTRACT FROM AUTHOR]

This study focuses on the experimental demonstration of the definition of kelvin using a triple point of water (TPW) cell and estimates the measurement uncertainty. The first part of this article is to construct the measurement setup and perform the measurements. The second stage is related with the calculation of uncertainty according to guides to the expression of uncertainty in measurement. The experiment in this study can be a practical and convenient method to show the unit as the fraction 1/273.16 of the thermodynamic temperature of the TPW, 273.16 K. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants 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.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China 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.)

Spherical weak blast propagation above a rough periodic surface is investigated by performing numerical simulations of the Euler equations. The study of the reflection pattern shows that waves diffracted by the surface asperities merge to form an effective reflected shock. It is initially detached from the incident shock but gradually catches up with it. If the source energy is sufficient, the reflected shock interacts with the incident one and Mach reflection occurs. Thus, the triple point has a similar trajectory to that over a smooth surface. In addition, the maximal overpressure is shown to be greater for small roughness scales in a layer near the surface. Far from the surface, it is close to that of a smooth surface for small roughness scales and to the free field for the highest ones. The increase in the maximal overpressure is related to oscillations on the waveforms that appear behind the shock. These properties are associated with the existence of a surface wave that propagates along the surface. Comparison of results in the linear regime with an analytic solution confirms this explanation. [ABSTRACT FROM AUTHOR]