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In this paper, a launching system with a novel charge structure was proposed to improve the interior ballistic performance. According to the working characteristics of the novel launching system, a lumped‐parameter model was established. The parameters of the propellant and the interior ballistic characteristics of the launching system were obtained by experiments. According to the experimental results, the accuracy of the lumped‐parameter model was verified by code. The simulated results were in good agreement with the experimental results. Based on the lumped‐parameter model, the propellant parameters, such as the impetus, the burning rate, the web thickness, and the charge mass, were investigated to understand the interior ballistic performances of the launching system. An optimization method was proposed to design the propellant parameters of the launching system. The results show that the optimal scheme can increase the velocity of the projectile by 9.54 %. Compared with the traditional launching method, the velocity of the projectile is increased by 37.09 % while the peak pressure in the barrel has no change. [ABSTRACT FROM AUTHOR]

Multiplicity fluctuations play a crucial role in relativistic heavy-ion collisions. In this work, we explore how the multiplicity fluctuations can be effectively suppressed in the measurement of particle correlations. In particular, through proper normalization, particle correlations can be evaluated in a manner irrelevant to multiplicity. When the multiplicity fluctuations are adequately extracted, Monte Carlo simulations show that the remaining correlations possess distinct features buried in the otherwise overwhelming fluctuations. Moreover, we argue that such a normalization scheme naturally agrees with the multi-particle correlator, which can be evaluated using the Q-vectors. The implications of the present study in the data analysis are also addressed. [ABSTRACT FROM AUTHOR]

Summary: Frequent germline mutations of HAVCR2, recently identified in subcutaneous panniculitis‐like T‐cell lymphoma (SPTCL), are associated with an increased risk of hemophagocytic lymphohistiocytosis (HLH). However, SPTCL‐HLH represents a challenge because of the difficulties in treatment with poor survival. Its malignant nature, specifically harbouring HAVCR2 mutations, has also been questioned. To better understand its pathology and treatment, we analysed the clinical data of six patients diagnosed at our centre. The median age at onset was 10.5 years (range, 0.8–12.4). Five patients presented with skin lesions of subcutaneous nodules/plaques and/or ulceration. All patients developed HLH; notably, one infant only had HLH without skin involvement. Histopathologically, only two patients were diagnosed with SPTCL and three were reported as panniculitis with no sufficient evidence of lymphoma. Genetically, germline homozygous mutation of HAVCR2 (p.Y82C) was identified in all patients, with a median diagnosis time of 4.6 months. All patients initially received corticosteroids, immunosuppressants or chemotherapy, achieving unfavourable responses. Strikingly, they responded well to ruxolitinib targeting inflammatory cytokines, allowing rapid disease resolution and/or long‐term maintenance of remission. The excellent efficacy of ruxolitinib highlights this disease as an inflammatory condition instead of neoplastic nature and indicates novel agents targeting key inflammatory pathways as an encouraging approach for this disease entity. [ABSTRACT FROM AUTHOR]

This study reports the Mach reflection of gaseous detonation on porous wedges experimentally, in which the porous wall is consisted of equidistant inline square columns. The smoked foil technique was utilized to monitor the evolution of the triple-point trajectory and detonation cells in the Mach stem region. In addition to the wedge angle and initial pressure of gaseous mixture, this paper also focuses on the effect of porosity and pore size on the Mach reflection and its mechanism. The results show that the strength of the Mach stem is significantly weakened by the porous media compared with that on the smooth wedge, which is ascribed to the diffraction and reflection waves generated by the interaction of the Mach stem front with the pore. Furthermore, the onset of the triple-point trajectory is delayed, the angle of which is decreased. The porosity and pore size present distinct influence on the Mach stem height. With the increase in the porosity and the decrease in the pore size, the Mach stem region is attenuated more dramatically and the Mach stem is harder to be formed or even could not be observed. Furthermore, the triple-point trajectory on the porous wall exhibits local self-similarity and satisfies the frozen limit in the near field and the equilibrium limit in the far field. However, the lengths of the existence of the frozen limit and the transition to the equilibrium limit on the porous wall are found to be much shorter than the hydrodynamic thickness, and the recovery of the self-similarity depends largely on the porosity and pore size. [ABSTRACT FROM AUTHOR]

We explore the quasiparticle model at the finite chemical potential related to Ru-Keng Su's distinguished contributions to the topic. In addition, we discuss the recent developments in the model, and in particular, one argues that the effective mass of the quasiparticle might attain a specific form as a function of momentum, in addition to its dependence on the temperature and chemical potential. Unlike the approaches based on the properties of underlying symmetry or the renormalization group, the momentum dependence emerges as a special solution to an integro-differential equation resulting from the underlying thermodynamic consistency. Moreover, this special solution to the problem is shown to be more general than previously explored in the literature. Instead of fitting to the lattice QCD data at the vanishing chemical potential, in this work, we adopt a "bottom-up" approach by assuming some analytic ansatzes that are manifestly thermodynamically consistent. The remaining physical quantities are subsequently derived, and possible implications are also addressed. [ABSTRACT FROM AUTHOR]

Porous materials can be used for accidental explosion prevention and suppression in process industries. In this study, an experimental study was conducted to study the effect of an aluminum foam plate on stoichiometric methane-oxygen detonation propagation behavior at different initial pressures (i.e., 10 kPa to 50 kPa). Experiments were carried out in a 4.4-m long, 48-mm diameter tube. Downstream of the foam plate, the detonation velocity was measured using even-spaced photodiodes, and the detonation structure evolution was recorded using the soot foil technique. The density of the aluminum foam was 1.1 g/cm3 and the thicknesses were 10 mm and 15 mm. Results demonstrate that behind the foam plate, the detonation fails first and re-initiates after a certain distance (re-initiation distance). At the end of the tube, the detonation velocity can be steady although the velocity fluctuation is significant downstream of the plate. The soot pattern indicates that the onset of detonation is achieved via the interaction between shock waves and wall, and fast turbulence mixing. For the case of the 10-mm foam plate, the single-headed mode can be observed. Generally, the re-initiation distance increases with the cell size. When the single-headed spin appears, the re-initiation distance is decreased notably. [ABSTRACT FROM AUTHOR]

In this study, a novel type of composite explosive was prepared by adding titanium fiber into the RDX explosive. The effects of the content of titanium fiber on the performance of the RDX explosive were systematically studied, and the optimal concentration was obtained by comparing its performances with the RDX explosive. Underwater explosion experiments showed the optimal concentration was 15 mass%, in which the value of specific bubble energy, as well as total energy was acquired the maximum. Especially, the energy density of composite explosive with 10 mass% titanium fiber was 10.64 kJ·cm−3, compared with aluminum fiber explosive, which was increased by 17.96%. Meanwhile, results of the MTS809 machine indicated that the optimal concentration was 19.16 volume%, in which the ultimate stress increased by 175%, and critical strain increased by 393%. Additionally, better mechanical properties ensured process safety in the course of transportation and storage of explosives. Therefore, titanium fiber could be a potential energetic additive and played double roles in improving the properties of the RDX explosive significantly including detonation performances and anti-pressure ability. [ABSTRACT FROM AUTHOR]