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We examine the stability of a spherically symmetric regular black hole when subjected to perturbations from a charged scalar field. This particular black hole is constructed by deforming the Minkowski spacetime. It has been observed that the charged superradiant instability arises only within a specific range of the deformation parameter, potentially resulting in an instability growth rate with a maximum magnitude of approximately Im (M ω) ∼ 10 - 3 . This growth rate significantly exceeds the instability identified in ABG black holes discussed in prior research, suggesting a notable timescale for detecting this phenomenon in astrophysical scenarios. Additionally, we conduct a thorough investigation into how the three parameters of the model influence the onset and intensity of the instability. Our analysis offers further insights into the possible emergence of this instability in spherical regular black holes and its association with the nonlinear effects of the electromagnetic field. [ABSTRACT FROM AUTHOR]

Nanofluidics holds significant potential across diverse fields, including energy, environment, and biotechnology. Nevertheless, the fundamental driving mechanisms on the nanoscale remain elusive, underscoring the crucial importance of exploring nanoscale driving techniques. This study introduces a Laplace pressure‐driven flow method that is accurately controlled and does not interfere with interfacial dynamics. Here, we first confirmed the applicability of the Young–Laplace equation for droplet radii ranging from 1 to 10 nm. Following that, a steady‐state liquid flow within the carbon nanotube was attained in molecular dynamics simulations. This flow was driven by the Laplace pressure difference across the nanochannel, which originated from two liquid droplets of unequal sizes positioned at the channel ends, respectively. Furthermore, we employ the Sampson formula to rectify the end effect, ultimately deriving a theoretical model to quantify the flow rate, which satisfactorily describes the molecular dynamics simulation results. This research enhances our understanding on the driving mechanisms of nanoflows, providing valuable insights for further exploration in fluid dynamics on the nanoscale. [ABSTRACT FROM AUTHOR]

We study the phenomenon of spontaneous scalarization in parameterized Schwarzschild-like black holes. Two metrics are considered, the Konoplya–Zhidenko metric and the Johannsen–Psaltis metric. While these metrics can mimic the Schwarzschild black hole well in the weak-field regime, they have deformed geometries in the near-horizon strong-field region. Such deformations notably influence the emergence of tachyonic instability and subsequent spontaneous scalarization, enabling a clear distinction between these parameterized metrics and the standard Schwarzschild metric. These results suggest a possible way to test the parameterized black holes and thus the Kerr hypothesis by observing the phenomenon of spontaneous scalarization. [ABSTRACT FROM AUTHOR]

Mass transport through the nanoporous medium is ubiquitous in nature and industry. Unlike the macroscale transport phenomena which have been well understood by the theory of continuum mechanics, the relevant physics and mechanics on the nanoscale transport still remain mysterious. Recent developments in fabrication of slit-like nanocapillaries with precise dimensions and atomically smooth surfaces have promoted the fundamental research on the molecular transport under extreme confinement. In this review, we summarized the contemporary progress in the study of confined molecular transport of water, ions and gases, based on both experiments and molecular dynamics simulations. The liquid exhibits a pronounced layered structure that extends over several intermolecular distances from the solid surface, which has a substantial influence on static properties and transport behaviors under confinement. Latest studies have also shown that those molecular details could provide some new understanding on the century-old classical theory in this field. [ABSTRACT FROM AUTHOR]

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The black liquor (BL) obtained by straw pulping can hardly be applied to conventional alkali recovery systems because of its high concentration of silicon and viscosity. Soda-oxygen pulping can synchronously deposit silica on the surface of the cellulose to reduce the silicon content and viscosity of BL remarkably. In this paper, the BLs of wheat straw soda-oxygen pulping obtained at different end points (pH < 10, 11.5 < pH < 12) and conventional soda-anthraquinone (soda-AQ) were obtained. The extent of silicon removal and viscosity reduction before and after centrifugation or membrane filtration as well as the thermodynamic properties of the BLs were investigated. Compared with that achieved by soda-AQ, over 45% silicon was removed from BL after soda-oxygen cooking at a similar delignification level. The total solid (TS) concentration of the soda-oxygen BL was easily concentrated by up to approximately 50%. SiO2 can be further removed by simple centrifugation and membrane filtration, and its TS could be increased to 60% at 300 mp s. With cooking end point further decreased pH < 10, the centrifugated BL had the lowest silica content, the highest volumetric isothermal expansivity (VIE) value, and the lowest pyrolysis temperature. [ABSTRACT FROM AUTHOR]

The back cover of the July 2024 issue of the journal Droplet features an image related to a research article titled "A strategy to drive nanoflow using Laplace pressure and the end effect" by Zhang et al. The article discusses the phenomenon of two droplets connected by a tube, where the larger droplet increases in size while the smaller droplet decreases until it disappears. The authors propose a theoretical strategy to drive nanoflow using the Laplace pressure based on this finding. The article is authored by Keli Zhang, Hengyu Xu, Jingcun Fan, Cancan Ouyang, Hengan Wu, and Fengchao Wang. [Extracted from the article]

The effects of low oxygen partial pressure (low-pO2) annealing and NO annealing on both performance and reliability of silicon carbide (SiC) MOS capacitors are verified, and the sequential annealing in low-pO2 and NO is also investigated. The sequential annealing is effective to improve the reliability of SiC MOS capacitors but shows slight deterioration of interface property. The results show that annealing in the atmosphere of low partial pressure oxygen changes the distribution of defect about the SiO2/SiC interface, and influences the following NO annealing effect. The mechanism of oxidation and annealing is discussed, and some suggestions on annealing are given. This experiment provides some inspiration for the combination of annealing processes and the optimization of annealing conditions. [ABSTRACT FROM AUTHOR]

The impact of 193 nm ArF pulsed UV laser irradiation on thermally grown SiO2/4H-SiC structures was investigated. The effect of pulsed UV light on the near-interface oxide trap of SiO2/SiC structure is greater than that on the interface and the near-interface SiC substrate. The defects near the interface do not change monotonously with the increase in irradiation power, which indicates that UV irradiation has at least two effects on SiO2/SiC. When the irradiation power is too high, new defects will be introduced into the oxide layer. This article reveals a potential mechanism for high-energy photon irradiation to change device performance in semiconductor plasma technology. [ABSTRACT FROM AUTHOR]

Here, we developed a novel electrochemiluminescence resonance energy transfer (ECL-RET) approach between Ru(bpy) and Au nanorods (NRs) for sensitive determination of HO. Au NRs were synthesized through silver ion-assisted seed-mediated method which exhibited an obvious absorption peak at about 627 nm. They were modified at glassy carbon electrode (GCE) surface which showed a significant ECL quenching efficiency about 56.5% due to the ECL-RET process. This Au NRs modified electrode was then utilized to measure the concentration of HO on the basis of the significant quenching effect of HO on Ru(bpy) ECL. Results demonstrated that the decrement of ECL intensity at Au NRs modified electrode had ~ 6.6-fold enhancement as compared with that at bare electrode. [ABSTRACT FROM AUTHOR]

Targeting more than one molecule in multifactorial diseases involving several disease mediators may provide improved therapeutic efficacy. Psoriasis is a multifactorial disease in which interleukin (IL)-6 and IL-23 are important disease mediators because they facilitate development of Th17 cells; widely accepted to be associated with psoriasis. To meet the need for new therapeutics, we aimed to create a clinically relevant bispecific drug, by combining the inhibitory properties of anti-IL-6 and anti-IL-23 antibodies, exhibiting high affinity, high stability and the ability to be produced in high yield. The bispecific molecule AZ17 was created by combining high affinity binding domains originating from monoclonal antibodies targeting human IL-6 and IL-23. To allow for high and efficient production, AZ17 was assembled by site-specific bioconjugation from two individual single chain fragment variables that were synthesized separately in Escherichia coli. To improve stability and extend pharmacokinetics, a flexible poly-ethylene glycol molecule was used as linker. In preclinical psoriasis models, AZ17 reduced IL-23-induced ear inflammation and improved psoriasis in a xenograft transplantation model where psoriasis skin is transplanted onto immune-deficient mice. The data presented here suggest AZ17 to be a promising drug candidate in psoriasis and other inflammatory diseases associated with Th17 cell development. [ABSTRACT FROM AUTHOR]

Solar magnetic activity exhibits a complex nonlinear behavior, but its dynamic process has not been fully understood. As the complex network technique can better capture the dynamics of nonlinear system, the visibility graphs (VG), the horizontal visibility graphs (HVG), and the limited penetrable visibility graphs (LPVG) are applied to implement the mapping of sunspot relative numbers in the northern and southern hemispheres. The results show that these three methods can capture important information of nonlinear dynamics existing in the long-term hemispheric sunspot activity. In the presentation of the results, the network degree sequence of the HVG method changes preferentially to the original data series as well as the VG and the LPVG, while both the VG and the LPVG slightly lag behind the original time series, which provides some new ideas for the nonlinear dynamics of the hemispheric asymmetry in the two hemispheres. Meanwhile, the use of statistical feature-skewness values and complex network visibility graphs can yield some complementary information for mutual verification. [ABSTRACT FROM AUTHOR]

Wafer bonding of a silicon carbide (SiC) diaphragm to a patterned SiC substrate coated with aluminum nitride (AlN) film as an insulating layer is a promising choice to fabricate an all-SiC capacitive pressure sensor. To demonstrate the bonding feasibility, a crystalline AlN film with a root-mean-square (RMS) surface roughness less than ~0.70 nm was deposited on a SiC wafer by a pulsed direct current magnetron sputtering method. Room temperature wafer bonding of SiC-AlN by two surface activated bonding (SAB) methods (standard SAB and modified SAB with Si nano-layer sputtering deposition) was studied. Standard SAB failed in the bonding, while the modified SAB achieved the bonding with a bonding energy of ~1.6 J/m2. Both the microstructure and composition of the interface were investigated to understand the bonding mechanisms. Additionally, the surface analyses were employed to confirm the interface investigation. Clear oxidation of the AlN film was found, which is assumed to be the failure reason of direct bonding by standard SAB. [ABSTRACT FROM AUTHOR]