A WSe
2
monolayer shows many interesting properties due to its spin-orbit coupling induced spin splitting in bands around the Fermi level and the spin-valley configuration. The orientation of the ...spin-polarization in the relevant bands is crucial for the nature of exciton states and the optical valley selectivity. In this work, we studied the electronic properties of the WSe
2
nanoribbons under different mechanical bending curvatures and electron/hole doping using density functional theory and their optical absorption and excitonic states using many-body perturbation GW and BSE (Bethe-Salpeter equation) methods. We found that the WSe
2
nanoribbons can exhibit an enhanced SOC effect and a spatially varying spin-polarization in bands around the Fermi level under bending conditions. The spin-polarization can show an anisotropy (or asymmetry) in these nearly degenerate bands, leading to a controllable magnetism
via
bending and electron/hole doping of the nanoribbons, suggesting a potential application in compact and controllable magnetic nanodevices and spintronics. The optical absorption spectrum of the nanoribbon presents a large tunability with bending within the near infrared region of about 0.4 to 1.5 eV, showing an enhanced absorption under a large bending condition. The exciton states generally show mixed or various spin configurations in the electron and hole pairs that are controlled by bending, potentially useful for applications in spin-based quantum information processes.
Bending induces the spatial variation of the spin-polarization and the modulation of the spin configuration in the exciton states in the WSe
2
nanoribbons, applicable for controlled spintronics and optoelectronics.
In this study, the significant iron-based material, hydroxyl-functionalized ball-milled zero-valent iron/Fe3O4 (HFB-ZVI/Fe3O4) was employed for the experiments. The performance of the Electro + ...HFB-ZVI/Fe3O4 + Oxone system for the degradation of chemical oxygen demand (COD) in antibiotic wastewater was investigated. A direct current was applied between a graphite plate anode and two iron plate cathodes, and a series of operational parameters, such as applied electric current, the dosage of HFB-ZVI/Fe
3
O
4
composite, the dosage of Oxone, and initial solution pH, were explored to evaluate the oxidation process. The application of electric current enhanced the gradual degradation of COD and the increase of current intensity accelerated COD degradation. The neutral condition was favourable for the rapid degradation of COD in a short reaction time by the Electro + HFB-ZVI/Fe3O4 + Oxone process and promoted the degradation efficiency of COD. An increase of electric current gradually decreased the reaction solution pH, the larger the electric current applied in the reaction process, the lower the final pH of the reaction solution. Under the optimal experimental conditions (1 g/L HFB-ZVI/Fe
3
O
4
composite, 0.3 g/L Oxone, current intensity = 500 mA, initial solution pH = 7.85), Electro + HFB-ZVI/Fe3O4 + Oxone achieved 99% COD degradation in antibiotic wastewater. Radicals quenching experiments indicated the contribution to COD degradation by hydroxyl radicals (HO
*
), sulphate radicals (SO
4
*-
) and other oxidants were 66.03%, 24.014% and 9.756%, respectively. The possible mechanism of COD degradation in the Electro + HFB-ZVI/Fe3O4 + Oxone system was also discussed in this study. The findings in this work provided useful information for the treatment of wastewater.
We have previously shown that compound-7g inhibits colorectal cancer cell proliferation and survival by inducing cell cycle arrest and PI3K/AKT/mTOR pathway blockage. However, whether it has the ...ability to exert antitumor activity in other cancer cells and what is the exact molecular mechanism for its antiproliferation effect remained to be determined. In the present study, compound-7g exhibited strong activity in suppressing proliferation and growth of glioblastoma cells. The inhibitor selectively downregulated F-box protein SKP2 expression and upregulated cell cycle inhibitor p27, and then resulted in G1 cell cycle arrest. Mechanism analysis revealed that compound-7g also provokes the down-regulation of E2F-1, which acts as a transcriptional factor of SKP2. Further results indicated that compound-7g induced an increase of LC3B-II and p62, which causes a suppression of fusion between autophagosome and lysosome. Moreover, compound-7g mediated autophagic flux blockage promoted accumulation of ubiquitinated proteins and then led to endoplasmic reticulum stress. Our study thus demonstrated that pharmacological inactivation of E2F-1-SKP2-p27 axis is a promising target for restricting cancer progression.
The use of agents to circle a moving target and estimate its states with bearing measurements only is a kind of passive tracking technique, and has received wide attention in recent years. However, ...the performance of the existing estimation and control laws for moving agent are still not so satisfactory when the target position is not known beforehand. In this paper, an unbiased estimator to locate the position of the target and a controller to circumnavigate around the target at a prescribed circular distance are investigated for an unmanned aircraft vehicle (UAV). First, a rough target-state estimator and a rough two-stage saturation UAV circumnavigation strategy are introduced, and their convergence performance is analyzed. Second, a virtual intersecting localization algorithm (VILA) is proposed based on a rough estimation strategy, and then the accurate target-state estimation is obtained with a Kalman filter. Third, the UAV rough circumnavigating strategy is modified with the accurate target-state estimation. By numerical simulation, it is verified that the steady estimation error with VILA is asymptotically unbiased, and the estimation accuracy is much higher than that of the existing estimation methods. It is also proven that the control error by the proposed UAV circumnavigating strategy can asymptotically converge to zero by the modified controller, which is also superior to that for the existing circumnavigating controller.
Abstract
Rapid advances in deep learning have brought not only a myriad of powerful neural networks, but also breakthroughs that benefit established scientific research. In particular, automatic ...differentiation (AD) tools and computational accelerators like GPUs have facilitated forward modeling of the Universe with differentiable simulations. Based on analytic or automatic backpropagation, current differentiable cosmological simulations are limited by memory, and thus are subject to a trade-off between time and space/mass resolution, usually sacrificing both. We present a new approach free of such constraints, using the adjoint method and reverse time integration. It enables larger and more accurate forward modeling at the field level, and will improve gradient-based optimization and inference. We implement it in an open-source particle-mesh (PM)
N
-body library
pmwd
(PM with derivatives). Based on the powerful AD system
JAX
,
pmwd
is fully differentiable, and is highly performant on GPUs.
In the context of extended probabilistic automata, this study focuses on an information flow property, called opacity, of discrete event systems. The achievement of this research is the formulation ...and in-depth analysis of what is termed sequential k-opacity. This metric, through its detailed assessment, marks an explicit and visible advancement beyond the existing paradigms for measuring system opacity. It introduces an improved method for analyzing the probability of event sequences leading to confidential states within a system. An approach of such a comprehensive nature is essential for a detailed analysis of opacity in systems typified by deterministic and stochastic elements. Furthermore, this work incorporates a numerical case study that provides a baseline for further investigations in practical applications, thereby validating the proposed framework's usefulness. The research progresses to explore novel approaches to the reinforcement and persistence of system opacity within extended probabilistic automata. Among these approaches, the strategic use of fake events is critical as it is a fundamental tool for enhancing system security and secrecy, which plays an important role in protecting sensitive and secret data by effectively hiding the real status of the system from outside inspection.
In this work, the characteristics of β-carotene nanodispersions prepared with sodium caseinate (SC), Tween 20, decaglycerol monolaurate (ML750) and sucrose fatty acid ester (L1695) using solvent ...displacement technique were compared. The mean particle size of the nanodispersions ranged from 30
nm to 206
nm, depending on the emulsifier used. SC-stabilized nanodispersions had the largest particles size, while those prepared with Tween 20 had the smallest. The mean particle size and size distribution of the nanodispersions generally remained unchanged after 8 weeks of storage time at 4
°C, but the β-carotene content in all nanodispersions decreased over time. The β-carotene in SC-stabilized nanodispersions was the most stable against oxidation among all samples, most likely due to the small specific surface area of the particles, physical barrier of SC protecting the encapsulated β-carotene against free radicals and the antioxidative activity of caseins. The combined effect of SC and ML750 or L1695 on the mean particle size and β-carotene retention was also investigated. Nanodispersions prepared with SC-ML750 or SC-L1695 showed larger mean particle sizes compared to those prepared with ML750 or L1695 alone. However, the stability of β-carotene in these systems was improved owing to the antioxidative activity of SC. This work demonstrated the importance of emulsifier in determining the characteristics and stability of β-carotene nanodispersions.
Visible-light-promoted sulfidation and phosphorylation of arylhydrazines for the synthesis of aromatic sulfides and diarylphosphoryl hydrazides were developed using the organic dyes rose bengal and ...Na
2
-eosin Y as photocatalysts, respectively. This strategy offers an efficient and mild transition-metal-free synthetic protocol for the formation of C-S and N-P bonds from arylhydrazines.
Visible-light-promoted sulfidation and phosphorylation of arylhydrazines for the synthesis of aromatic sulfides and diarylphosphoryl hydrazides were developed using the organic dyes rose bengal and Na
2
-eosin Y as photocatalysts, respectively.
The n‐i‐p type perovskite solar cells suffer unpredictable catastrophic failure under operation, which is a barrier for their commercialization. The fluorescence enhancement at Ag electrode edge and ...performance recovery after cutting the Ag electrode edge off prove that the shunting position is mainly located at the edge of device. Surface morphology and elemental analyses prove the corrosion of the Ag electrode and the diffusion of Ag+ ions on the edge for aged cells. Moreover, much condensed and larger Ag clusters are formed on the MoO3 layer. Such a contrast is also observed while comparing the central and the edge of the Ag/Spiro‐OMeTAD film. Hence, the catastrophic failure mechanism can be concluded as photon‐induced decomposition of the perovskite film and release reactive iodide species, which diffuse and react with the loose Ag clusters on the edge of the cell. The corrosion of the Ag electrode and the migration of Ag+ ions into Spiro‐OMeTAD and perovskite films lead to the forming of conducting filament that shunts the cell. The more condensed Ag cluster on the MoO3 surface as well as the blocking of holes within the Spiro‐OMeTAD/MoO3 interface successfully prevent the oxidation of Ag electrode and suppress the catastrophic failure.
The catastrophic failure of n‐i‐p type perovskite solar cells under operation is reported, which is proven by the corrosion of the metal electrode on the edge. After inserting a thin MoO3, the improved Ag thin film morphology as well as better energy alignment suppress the catastrophic failure of perovskite solar cells.
We demonstrate semipolar (20-21) micro-LED-based high-bandwidth WLEDs utilizing perovskite QDs and organic emitters in color-conversion films. The WLEDs exhibit a bandwidth in excess of 1 GHz and a ...CCT of 6141 K, making these devices suitable for visible light communication and lighting applications.
Pictorial representation of high-bandwidth WLEDs by utilizing combinations of perovskite quantum dots (PQDs) and organic materials as color converters under the excitation of a semipolar blue micro-LED.
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