[en] In this paper, we study possible signatures of binary planets or exomoons on the Rossiter-McLaughlin (R-M) effect. Our analyses show that the R-M effect for a binary planet or an exomoon during its complete transit phase can be divided into two parts. The first is the conventional one similar to the R-M effect from the transit of a single planet, of which the mass and the projected area are the combinations of the binary components; the second is caused by the orbital rotation of the binary components, which may add a sine- or linear-mode deviation to the stellar radial velocity curve. We find that the latter effect can be up to several ten m s^–1. Our numerical simulations as well as analyses illustrate that the distribution and dispersion of the latter effects obtained from multiple transit events can be used to constrain the dynamical configuration of the binary planet, such as how the inner orbit of the binary planet is inclined to its orbit rotating around the central star. We find that the signatures caused by the orbital rotation of the binary components are more likely to be revealed if the two components of a binary planet have different masses and mass densities, especially if the heavy one has a high mass density and the light one has a low density. Similar signatures on the R-M effect may also be revealed in a hierarchical triple star system containing a dark compact binary and a tertiary star.

[en] Nanocomposites of La_2/3Ca_1/3MnO₃(LCMO)/xCuMn₂O₄ (0 ≤ x ≤ 40%) have been prepared by a citrate gel route and characterized for microstructural and magnetotransport properties. Results show that fabrication with CuMn₂O₄ has an important effect on the electrical transport behaviour of the composites. With the increment of CuMn₂O₄ content x, the metal-insulator transition temperature T_MI for the composites shifts downwards and the resistivity increases. The susceptibility analysis indicates that the composites with x = 4, 20, 30 and 40% have a similar paramagnetic-ferromagnetic transition temperature T_C ∼ 240 K, which is lower than T_C of pure LCMO (∼262 K). The high temperature (T > T_MI) semi-conducting part of the resistivity (ρ) data follows a small polaron hopping conduction mechanism, and the metallic behaviour of the samples (T < T_MI) fits the model in terms of electron-magnon scattering of the carriers. Furthermore, a significant enhancement both in low-field magnetoresistance (LFMR) and in high-field magnetoresistance (MR) is observed for the composites at a wide temperature range below T_MI. The LFMR measured at 0.3 T reaches the maximum for the x = 40% sample when T = 10 K with the value of ∼23%, which is much larger than that of the pure LCMO (∼6.9%). We argue that such an enhancement in MR is attributed to the enhanced spin-polarized tunnelling, which is manipulated by the spin disorder at the LCMO surfaces caused by CuMn₂O₄ addition

[en] Thermal stratification in pipes could lead to thermal fatigue sometimes challenging the reactor safety. This paper is a study about using synchronized CFD technique to analyze the flow field and thermal stratification within the non-isolated pipes to the reactor vessel of the small modular reactor. The simulation shows that the stratification phenomenon within the pipes is mainly caused by the fluid buoyancy lift between cold and hot fluids. Possible locations where the thermal stratification could occur were found, which helps to improve the system design to mitigate the effect of thermal stratification such as by increasing the slope of the pipe or setting a vertical section at the hot pipe nozzle. (authors)

[en] The validity of the cosmic distance-duality (DD) relation is investigated by using 91 measurements of the gas mass fraction of galaxy clusters recently reported by the Atacama Cosmology Telescope (ACT) and the luminosity distance from the Union2.1 type Ia supernova (SNIa) sample independent of any cosmological models and the value of the Hubble constant. We consider four different approaches to derive the gas mass function and two different parameterizations of the DD relation, and find that they have very slight influences on the DD relation test and the relation is valid at the 1σ confidence level. We also discuss the constraints on α and β , which represent the effects of the shapes and colors of the light curves of SNIa, respectively. Our results on α and β are different from those obtained from the ΛCDM model and the galaxy cluster plus SNIa data. (paper)

[en] We analyze the attractor behaviour of the inflation field in braneworld scenarios using the Hamilton—Jacobi formalism, where the Friedmann equation has the form of H² = ρ + ε √2ρ0ρ or H² = ρ+inρ²/2σ, with in = ±1. We find that in all models the linear homogeneous perturbation can decay exponentially as the scalar field rolls down its potential. However, in the case of a −ρ² correction to the standard cosmology with ρ < σ, the existence of an attractor solution requires (σ − ρ)/φ² > 1. Our results show that the perturbation decays more quickly in models with positive-energy correction than in the standard cosmology, which is opposite to the case of negative-energy correction. Thus, the positive-energy modification rather than the negative one can assist the inflation and widen the range of initial conditions. (geophysics, astronomy, and astrophysics)

[en] The electrical transport and magnetoresistance (MR) properties of the composites (1 - x)La_0.67Sr_0.33MnO₃ (LSMO)/x Sb₂O₅ with different Sb₂O₅ molar percentages x were investigated. Experimental results show that the Sb₂ O₅ addition plays a key role in the electrical transport behaviour of the composites. Different transport and MR behaviours are observed for x ≤ 2% and x≥2%. Compared with pure LSMO, an enhanced MR effect for the composites is found over a wide temperature range under applied magnetic fields of both 0.3 and 3 T. Specially, a large and constant MR value of ∼18% is observed at room temperature, which is attractive for the study of applications. We argue that such an enhancement in MR is attributed to the magnetic disorder at the LSMO grain surfaces or boundaries caused by the Sb₂O₅ addition. Moreover, the resistivity (ρ) versus T curves for x = 1% and 2% samples fit well to the phenomenological model derived from spin-polarized tunnelling at grain boundaries and thermal activation. This result confirms that the grain boundaries have been modified in the composites with low Sb₂O₅ addition and provides information about the microscopic transport mechanism in the system

[en] The Sandage-Loeb (SL) test is a direct measurement of the cosmic expansion by probing the redshift drifts of quasi-stellar objects in the ‘redshift desert’ of 2 < z < 5. In this work, we investigate its constraints on the unified dark energy and dark matter models including the generalized Chaplygin gas and the superfluid Chaplygin gas. In addition, type Ia supernovae (SNIa) data and the distance ratios derived from the cosmic microwave background radiation and baryon acoustic oscillation observations (CMB/BAO) are also used. We find that the mock SL data gives the tightest constraints on the model parameters and it can help to reduce the parameter regions allowed by the present SNIa+CMB/BAO by about 75% when all datasets considered are combined. Thus the SL test is a worthy and long awaited measurement to probe effectively the cosmic expanding history and the properties of dark energy. (paper)

[en] This study demonstrated an effective technique for construction of neovascularized cutaneous cartilage flaps. The central vessels of the pinna and a piece of cartilage were dissected out and placed in a subcutaneous flap pocket of a random-pattern, distally based flap. The neovascularization progress began in 1 week. At 3rd to 4th week, the outgrowth achieved the highest level, and new vessels anastomose in the flaps. In the meantime, new cartilage cells formed

[en] The study was performed based on numerical CFD simulation by means of dynamic meshing. A CFD model was established to reproduce the valve opening behavior, which means that a dynamic valve disc model has been built using the trimmed volume mesh and the deformable mesh coupled with 1 D freedom model of the valve disc. The simulation shows that the total opening time of the pilot-valve is principally affected by the steam discharging time, the disc motion time of about 0.1 s. The disc movement characteristics was similar at different pressure conditions, and the higher the pressure, the longer the disc opening time, but the shorter the disc motion time. (authors)

[en] To investigate the preparation of radioiodinated MnTBAP and its biodistribution in mice, MnTBAP was labeled with ¹³¹I using the iodogen method. the radiolabeled compound was characterized by polymide TLC, in which the substratum of saline was used as developing agent. Biodistribution studies were carried out in KM mice. At different times after radiopharmaceutical i.v. administration(185 kBq ¹³¹I-MnTBAP/mouse, n = 6), the animals were sacrificed. Blood samples and the tissues of interested were collected, weighted and counted. The percent injected does per gram(%ID/g) was calculated for each sample. The labeling yield of ¹³¹I-MnTBAP is 96.3% and its radiochemical purity(RCP) are 96%, 95% and 94.5% at 2, 24 and 48 h, respectively. Biodistribution in mice demonstrates that ¹³¹I-MnTBAP is extensive, and it is metabolized mainly in liver and kidney, as indicated by their uptake of 8.34%ID/g and 12.23%ID/g at 5 min, 0.34%ID/g and 0.73%ID/g at 4 h, respectively. The results also show that ¹³¹I-MnTBAP could not penetrate the blood-brain barrier. The activity in thyroid increases with time. In conclusion, ¹³¹I-MnTBAP is stable and it is metabolized mainly in liver and kidney, worthy of further investigation to trace the compound in vivo and in vitro. (authors)