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Wingtip vortex is the initial phase of aircraft wake flow that jeopardizes flight safety. Previous studies have focused on the effect of incidence angle on tip vortex flow; thus, investigations on tip vortex in the roll-up stage under crosswind conditions are limited. In the present study, two NACA0012 wings with different tip shapes (round and square) were numerically analyzed to explore the effects of wingtip configurations on tip vortex. In addition, the effects of crosswinds on wingtip vortex evolution were also investigated. It was found that sharp edges of the square wingtip generated a multi-vortex system, resulting in a larger turbulent wake vortex core radius. The lift and vortex strength of the square wingtip were 23% higher and only 12% stronger than those of the round wingtip, respectively. Furthermore, crosswinds changed both the pressure distribution and the vortex structure. Crosswinds made the flow field unstable; hence, upwind lower edge vortices of the square wingtip burst earlier and merged faster. Consequently, the tightness of the upwind vortex of the square wingtip increased, and the corresponding vortex strength was enhanced. The downwind vortex of the square wingtip was weakened by 2.7% under a crosswind velocity of 4 m/s, whereas the downwind tip vortex of the round wingtip was strengthened under the same conditions.

Understanding the complex action mechanism of appetite regulation peptides can significantly impact therapeutic options in the treatment of obesity and other metabolic diseases. Hypothalamic α-melanocyte-stimulating hormone (α-MSH) is an anorexigenic peptide, closely related to the occurrence of obesity, playing a central role in food intake and energy expenditure. In the central nervous system (CNS), α-MSH is cleaved from proopiomelanocortin (POMC) and then released into different hypothalamic regions to act on melanocortin 3/4 receptor (MC3/4R)-expressing neurons, lowering food intake and raising energy expenditure via appetite suppression and sympathetic nervous system. Furthermore, it can increase the transmission of some anorexigenic hormones (e.g., dopamine) and interact with other orexigenic factors (e.g., agouti-related protein, neuropeptide Y) to influence food reward rather than merely feeding behavior. Therefore, α-MSH is a critical node of the hypothalamus in transmitting appetite suppression signals and is a key component of the central appetite-regulating circuits. Herein, we describe the role of α-MSH in appetite suppression in terms of specific receptors, effector neurons, sites of action, and the interaction with other appetite-relative peptides, respectively. We focus on the role of α-MSH in obesity. The status of research on α-MSH-related drugs is also discussed. With the intention of illuminating a new approach for targeting α-MSH in the hypothalamus as a strategy to manage obesity, we hope to further understand the direct or indirect mechanisms by which α-MSH exerts its appetite-regulating effects.

N-doping and phase regulation of MoS2via room temperature NH3 plasma technology achieve efficient bidirectional catalysis for lithium–sulfur electrochemistry.

N-doped NiCoO2/CoO nanoarrays with an optimized electronic structure facilitate the formation/decomposition of flake-like amorphous Li2O2 synergistically in lithium–oxygen batteries.

Nitrogen reduction reaction (NRR) under ambient conditions is always a long-standing challenge in science, due to the extreme difficulty in breaking the strong N N triple bond. The key to resolving this issue undoubtedly lies in searching superior catalysts to efficiently activate and hydrogenate the stable nitrogen molecules. We herein evaluate the feasibility of WP2 for N2 activation and reduction, and first demonstrate WP2 with an impressive ammonia yield rate of 7.13 μg h−1 cm−2, representing a promising W-based catalyst for NRR. DFT analysis further reveals that the NRR catalysis on WP2 proceeds in a distal reaction pathway, and the exceptional NRR activity is originated from superior surface electron energy level matching between WP2 and NRR potential which facilitates the interfacial proton-coupled electron transfer dynamics. The successfully unraveling the intrinsic catalytic mechanism of WP2 for NRR could offer a powerful platform to manipulate the NRR activity by tuning the electron energy levels.

Ergosterol peroxide (EP) in Anoectochilus elwesii possesses antioxidant and anticancer properties, yet few studies have been focused on its mechanisms and directed detecting. By practicing HPTLC-DPPH coupled with UHPLC-ESI-TOF MS, EP was located and the cytotoxic activity of EP was performed by MTT method. The apoptosis studies were conducted on SGC-7901cells by AO/EB and Annex V/PI staining method, PI flow cytometric assay, reactive oxygen species detection and mitochondrial membrane potential assay. An effect-directed detecting method of HPTLC-DPPH/UHPLC/ESI-TOF-MS was developed for EP rapidly and precisely, providing an option for identifying oxidative compounds. EP exhibits high cytotoxic activity against SGC-7901 gastric cancer cells and the morphological apoptosis suggested that EP induced apoptosis and cell cycle arrest in G0/G1 phase. It could enhance the ROS level and cause a decrease in the mitochondrial membrane potential. Its antiproliferative mechanism is G0/G1 phase arrest and might be traced through ROS-mediated mitochondrial dysfunction pathways.

The high unoccupied d band energy of Ni3N basically results in weak orbital coupling with water molecule, consequently leading to slow water dissociation kinetics. Herein, we demonstrate Cr doping can downshift the unoccupied d orbitals and strengthen the interfacial orbital coupling to boost the water dissociation kinetics. The prepared Cr-Ni3N/Ni displays an impressive overpotential of 37 mV at 10 mA·cmgeo−2, close to the benchmark Pt/C in 1.0 M KOH solution. Refined structural analysis reveals the Cr dopant exists as the Cr-N6 states and the average d band energy of Ni3N is also lowered. Density functional theory calculation further confirms the downshifted d band energy can strengthen the orbital coupling between the unpaired electrons in O 2p and the unoccupied state of Ni 3d, which thus facilitates the water adsorption and dissociation. The work provides a new concept to achieve on-demand functions for hydrogen evolution catalysis and beyond, by regulating the interfacial orbital coupling.

Tungsten oxide with strong acid resistance and weak O-binding ability could potentially achieve a tradeoff on the O-binding properties by constructing W and Ir dual sites for acidic oxygen evolution reaction (OER) catalysis. However, the peroxide intermediate formed during the OER process could react with tungsten oxide to produce soluble species, thereby severely limiting its application. Herein, we construct Ir–W@Ir–WO3−x core–shell nanoparticles with an Ir–W metallic core and an Ir-doped WO3−x (Ir–WO3−x) shell, which can deliver an impressive overpotential of 261 mV at 10 mA cm−2 for acidic OER catalysis and extraordinary catalytic stability. Spectroscopic analysis manifests that Ir–W@Ir–WO3−x could substantially suppress peroxide species formation and effectively avoid peroxide-induced corrosion during the OER process. Theoretical studies reveal that the moderate O-binding capability on Ir–W@Ir–WO3−x not only accelerates catalytic kinetics, but also restrains hydroperoxide formation. This work sheds light on the rational design of OER catalysts by modulating the adsorption behavior of oxygen-containing intermediates.

Since water dissociation and H desorption kinetics essentially determine the performance of the alkaline hydrogen evolution reaction (HER), rationally regulating surface adsorption behavior to achieve a superior catalytic surface is always challenging for catalysts. Herein, N-doped Pt–Ru single atom alloy electrocatalysts were constructed by dispersing diluted Pt single atoms onto Ru nanoparticles by thermal annealing in an ammonium atmosphere. The prepared (Ru–N)@Pt can substantially boost the alkaline HER catalysis of Ru nanoparticles and deliver an impressive overpotential of only 15 mV at 10 mA cm−2. X-ray-absorption fine structure characterization confirms that the doped N species have bonding interaction with both Ru and Pt sites. Theoretical calculations reveal that N incorporation helps strengthen the interfacial interaction between H2O and Ru sites by precise orbital engineering, while the Pt sites facilitate the H2 desorption kinetics. This work not only provides an effective strategy to construct single atom alloy electrocatalysts for a high-performance alkaline HER, but also sheds light on the understanding of the reaction mechanism at the atomic level.

Molybdenum disulfide (MoS2) has been recognized as one of the most promising candidates to replace precious Pt for hydrogen evolution reaction (HER) catalysis, due to the natural abundance, low cost, tunable electronic properties, and excellent chemical stability. Although notable processes have been achieved in the past decades, their performance is still far less than that of Pt. Searching effective strategies to boosting their HER performance is still the primary goal. In this review, the recent process of the electronic regulation of MoS2 for HER is summarized, including band structure engineering, electronic state modulation, orbital orientation regulation, interface engineering. Last, the key challenges and opportunities in the development of MoS2-based materials for electrochemical HER are also discussed.

Precisely constructing the local configurations of active sites to achieve on-demand catalytic functions is highly critical yet challenging. Herein, an anion-deficient strategy to precisely capture Ru single atoms on the anion vacancies of CoP

The interstitial structure and weak Ni-N interaction of Ni3N lead to high unoccupied d orbital energy and unsuitable orbital orientation, which consequently results in weak orbital coupling with H2O and slow water dissociation kinetics for alkaline hydrogen evolution catalysis. Herein, we successfully lower the unoccupied d orbital energy of Ni3N to strengthen the interfacial electronic coupling by employing the strong electron pulling capability of oxygen dopants. The prepared O-Ni3N catalyst delivers an overpotential of 55 mV at 10 mA cm−2, very close to the commercial Pt/C. Refined structural characterization indicates the oxygen incorporation can decrease the electron densities around the Ni sites. Moreover, density functional theory calculation further proves the oxygen incorporation can create more unoccupied orbitals with lower energy and superior orientation for water adsorption and dissociation. The concept of orbital-regulated interfacial electronic coupling could offer a unique approach for the rational design of hydrogen evolution catalysts and beyond.

With the change of life style, glucolipid metabolic disorders (GLMD) has become one of the major chronic disorders causing public health and clinical problems worldwide. Previous studies on GLMD pay more attention to peripheral tissues. In fact, the central nervous system (CNS) plays an important role in controlling the overall metabolic balance. With the development of technology and the in-depth understanding of the CNS, the relationship between neuro-endocrine-immunoregulatory (NEI) network and metabolism had been gradually illustrated. As the hub of NEI network, hypothalamus-pituitary-adrenal (HPA) axis is important for maintaining the balance of internal environment in the body. The relationship between HPA axis and GLMD needs to be further studied. This review focuses on the role of HPA axis in GLMD and reviews the research progress on drugs for GLMD, with the hope to provide the direction for exploring new drugs to treat GLMD by taking the HPA axis as the target and improve the level of prevention and control of GLMD.

In this paper, a reliability evaluation method for warm standby embryonic cellular array, based on k-out-of-n warm standby system reliability model and non-homogeneous continuous time Markov model, is proposed in order to evaluate the reliability more accurately. In reliability evaluation process, spare cells are in warm standby mode, and embryonic cell fault detection coverage and fault self-repairing success rate are considered. Experimental results show that the proposed reliability evaluation method can evaluate the reliability of embryonic cellular array effectively and improve its accuracy. Based on the proposed reliability evaluation method, the effects of parameters change on embryonic cellular array reliability are researched. By improving embryonic cell fault detection coverage and fault self-repairing success rate, and reducing embryonic cell failure rate, the reliability can be improved effectively. The higher the fault detection coverage and fault self-repairing success rate, the larger the growth rate of reliability. In addition, by increasing the scale of embryonic cellular array, the reliability increases to the maximum first, then it will decrease continuously. The reliability variation law can not only provide theoretical guidance for embryonic cellular array optimization design, but also point out the direction for further research.

A promising anode material for lithium-ion batteries (LIBs) consisting of ultrafine N-doped TiO₂ nanoparticles and N-doped carbon composite has been prepared by an effective sol-gel-calcined strategy. The synergetic effect between N-doped TiO₂ nanoparticles and N-doped carbon provides not only high conductivity paths and strong electron contact interface, but also supply a large surface area along with hindering the nanoparticles aggregation, resulting in excellent lithium-storage performance. When tested as an anode material for LIBs, a high capacity of 292.7 mAh g-1 can be retained after 50 cycles at 0.5 C. Even at 8 C, a satisfactory capacity of 160.3 mAh g-1 can be delivered. These features suggest the N-doped TiO₂/C composite a viable choice for application as an anode material in high-power LIBs.

Due to the limitations of the existing fault detection methods in the embryonic cellular array (ECA), the fault detection coverage cannot reach 100%. In order to evaluate the reliability of the ECA more accurately, embryonic cell and its input and output (I/O) resources are considered as a whole, named functional unit (FU). The FU fault detection coverage parameter is introduced to ECA reliability analysis, and a new ECA reliability evaluation method based on the Markov status graph model is proposed. Simulation experiment results indicate that the proposed ECA reliability evaluation method can evaluate the ECA reliability more effectively and accurately. Based on the proposed reliability evaluation method, the influence of parameters change on the ECA reliability is studied, and simulation experiment results show that ECA reliability can be improved by increasing the FU fault detection coverage and reducing the FU failure rate. In addition, by increasing the scale of the ECA, the reliability increases to the maximum first, and then it will decrease continuously. ECA reliability variation rules can not only provide theoretical guidance for the ECA optimization design, but also point out the direction for further research.

Summary Evaporation-condensation of red phosphorous to prepare phosphorous-based anodes inevitably generates white P residual, severely limiting its practical application due to the serious safety concern. Rather than removing the white P residual by complicated post-treatments, essentially prohibiting the generation of white P is a more meaningful alternative, but unfortunately it has been rarely studied so far. Herein, we demonstrate that the generation of white P can be substantially suppressed via sulfur-mediated phosphorous activation. Moreover, the prepared sulfur-doped P also exhibits the ever-reported fastest redox kinetics for sodium-ion storage. Electron spin resonance spectra and density functional theory calculations reveal that the introduced sulfur lives in the high-spin state during the evaporation-condensation process, which could activate P4 for polymerization. Meanwhile, sulfur-induced electron delocalization can also accelerate the Na-P redox kinetics. The capability to modulate phosphorus polymerization via the high-spin mediator could revolutionize the application of phosphorous for batteries and beyond.

Summary N-functionalization of amines with CO2 and H2 is one of the most important processes to make use of CO2. Although noble metal-based catalysts with remarkable performance have been widely used in this process, developing efficient non-noble-metal-based catalysts remains a grand challenge. Herein, we report In2O3 nanocrystals with high density of grain boundaries (HGB-In2O3), which show excellent activity toward methylation of amines. Impressively, HGB-In2O3 achieved the optimal yield of 82.7% for N,N-dimethylaniline with a mass activity of 21.2 mmol·g−1h−1 in methylation of N-methylaniline, comparable to noble-metal-based catalysts. As a bonus, HGB-In2O3 held noticeable stability, remarkable selectivity, and comprehensive applicability. Further mechanistic studies revealed that the presence of high density of grain boundaries not only facilitated the adsorption and activation of CO2 to generate CH3OH as the intermediate but also enhanced the activation of N-H bond in amines, contributing to the attractive activity of HGB-In2O3 toward methylation of amines., Graphical Abstract, Highlights • We prepared In2O3 nanocrystals with high density of grain boundaries (HGB-In2O3) • HGB-In2O3 gained 82% yield of N,N-dimethylaniline in N-methylaniline methylation • The grain boundaries in In2O3 facilitated the adsorption and activation of CO2 • The grain boundaries in In2O3 enhanced the activation of N-H bond in amines, Catalysis; Materials Characterization Techniques; Nanomaterials

Molybdenum disulfide is naturally inert for alkaline hydrogen evolution catalysis, due to its unfavorable water adsorption and dissociation feature originated from the unsuitable orbital orientation. Herein, we successfully endow molybdenum disulfide with exceptional alkaline hydrogen evolution capability by carbon-induced orbital modulation. The prepared carbon doped molybdenum disulfide displays an unprecedented overpotential of 45 mV at 10 mA cm−2, which is substantially lower than 228 mV of the molybdenum disulfide and also represents the best alkaline hydrogen evolution catalytic activity among the ever-reported molybdenum disulfide catalysts. Fine structural analysis indicates the electronic and coordination structures of molybdenum disulfide have been significantly changed with carbon incorporation. Moreover, theoretical calculation further reveals carbon doping could create empty 2p orbitals perpendicular to the basal plane, enabling energetically favorable water adsorption and dissociation. The concept of orbital modulation could offer a unique approach for the rational design of hydrogen evolution catalysts and beyond., Technologies allowing for sustainable hydrogen production will contribute to the decarbonization of the future energy supply. Here the authors report that carbon induced orbital modulation can facilitate the otherwise inert MoS2 electrocatalyst superior alkaline hydrogen evolution reactivity.

Embryonic Array (EA) with different configuration methods will directly affect its reliability and hardware consumption. At present, EA configuration design is lack of quantitative analysis method. In order to reasonably optimize EA configuration design, an EA configuration optimization design method is proposed, which is based on the constraints of EA hardware consumption and reliability. Through the analysis of EA working process and composition, quantitative analysis of EA reliability and hardware consumption are completed. Based on the constraints of EA hardware consumption and reliability, the mathematical model of EA configuration optimization design is established, which transfers EA configuration optimization design into an integer nonlinear programming model problem. According to the difference of the fitness value of individual waiting for mutation in population, adaptive mutation operator and crossover operator are selected, and a novel Modified Adaptive Differential Evolution (MADE) algorithm is proposed, which is used to solve EA configuration optimization design problem. Simulation experiments and analysis indicate that the MADE is able to effectively improve the speed, accuracy and stability of algorithm. Moreover, the proposed EA configuration optimization design method can select the most reasonable EA configuration design, and play an important guiding role in EA optimization design. Keywords: Configuration optimization, Differential evolution, Embryonic electronic, Hardware consumption, Integer nonlinear programming model, Reliability, Self-repairing

Although Ni3N possesses superior hydrogen desorption behavior, its alkaline hydrogen evolution reaction (HER) catalysis is substantially hindered, due to the high-lying unoccupied orbital center induced sluggish water dissociation kinetics. Herein, we successfully endow Ni3N with exceptional alkaline HER activity by in situ interfacial engineering. The prepared Ni3N/MoO2 interfacial system delivers an ultra-small overpotential of 21 mV at 10 mA cm−2, which is very close to that of the benchmark Pt/C catalysts. Density functional theory (DFT) calculations reveal that MoO2 with a lower unoccupied orbital center could substantially boost the water dissociation kinetics, while the hydrogen desorption proceeds on Ni3N. The capability to understand and design interfacial systems provides an effective pathway for the rational construction of HER catalysts and beyond.

Some new insights into traditional metal pretreatment of anticorrosion for high stable Zn metal anodes are provided. A developed pretreatment methodology is employed to prefer the crystal plane of polycrystalline Zn and create 3.26 µm protective coatings mainly consisting of organic polymers and zinc salts on Zn foils (ROZ@Zn). In this process, Zn metal exhibits a surface-preferred (001) crystal plane proved by electron backscattered diffraction. Preferred (001) crystal planes and ROZ coatings can regulate Zn