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Unmanned Aerial Vehicles (UAVs) have emerged as efficient tools in disaster-stricken areas, facilitating efficient data dissemination for post-disaster rescue operations. However, the limited onboard energy of UAVs imposes significant constraints on their operational lifespan, thereby presenting substantial challenges for efficient data dissemination. Therefore, this work investigates a data dissemination scheme to enhance the UAVs’ bandwidth efficiency in multi-UAV-enabled Internet of Vehicles, thereby reducing UAVs’ energy consumption and improving overall system performance when UAVs hover along designated flight trajectories for data dissemination. Specifically, first, we present a software-defined network-based framework for data dissemination in multi-UAV-enabled IoV. According to this framework, we formulate a problem called C2BS (Coding-based Cooperative Broadcast Scheduling) that focuses on optimizing the UAVs’ bandwidth efficiency by leveraging the combined benefits of coding and caching. Furthermore, we demonstrate the NP-hardness of the C2BS problem by employing a polynomial time reduction technique on the simultaneous matrix completion problem. Then, inspired by the benefits offered by genetic algorithms, we propose a novel approach called the Genetic algorithm-based Cooperative Scheduling (GCS) algorithm to address the C2BS problem. This approach encompasses a coding scheme for representing individuals, a fitness function for assessing individuals, operators (i.e., crossover and mutation) for generating offspring, a local search technique to enhance search performance, and a repair operator employed to rectify infeasible solutions. Additionally, we present an analysis of the time complexity for the GCS algorithm. Finally, we present a simulation model to evaluate the performance. Experimental findings provide evidence of the excellence of the proposed scheme.

It is still a great challenge to achieve high selectivity of ethanol in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials and lower energy barrier of possible other C2+ products. Here, we report a MOF‐based supported low‐nuclearity cluster catalysts (LNCCs), synthesized by electrochemical reduction of three‐dimensional (3D) microporous Cu‐based MOF, that achieves a single‐product Faradaic efficiency (FE) of 82.5 % at −1.0 V (versus the reversible hydrogen electrode) corresponding to the effective current density is 8.66 mA cm−2. By investigating the relationship between the species of reduction products and the types of catalytic sites, it is confirmed that the multi‐site synergism of Cu LNCCs can increase the C−C coupling effect, and thus achieve high FE of CO2–to–ethanol. In addition, density functional theory (DFT) calculation and operando attenuated total reflectance surface‐enhanced infrared absorption spectroscopy further confirmed the reaction path and mechanism of CO2–to–EtOH. [ABSTRACT FROM AUTHOR]

Manufacturing two‐dimensional (2D) materials or nanosheets with desired crystal faces originating from an established intrinsic 3D structure is a significant challenge. Herein, an intrinsic t3D metal–organic frameworks (MOFs) can be exfoliated into ultrathin metal–organic nanosheets with (001) and (101) crystal faces, which is regulated by the solute's shard and soft acid−base and pH value in the exfoliating solution. The inorganic ligands (with different charges) possessing the similar hardness of Lewis acid‐base of metal center can replace some of the organic ligands along the established crystal faces of the 3D MOFs with different electrostatic potentials, resulting in the exfoliating of the 3D MOFs into metal–organic nanosheets with different crystal faces. Using the Knoevenagel reaction as the catalytic reaction model, the catalytic activity of (001) crystal faces is three times that of (101) crystal faces, which is determined by the different locations of open metal sits in the 3D lamellar structure, further confirming the occurrence of oriented exfoliation. [ABSTRACT FROM AUTHOR]

A certain type of proportional valve has been optimised in design by adding a damping hole in its structure, which solves the problem of pressure rise in the fuel chamber due to gap leakage when closing. An integrated circuit electromagnetic model is used to mesh the model. Based on FLUENT software, the flow characteristics of the proportional valve at different valve opening have been analysed to get the curve of turbulent kinetic energy, pressure, and flow in internal field changing with different valve opening. The results show that the proportional valve with a damping hole has faster response speed and less pressure loss at the inlet and outlet of the valve. The data and conclusion obtained in this study are very important for the performance improvement of the proportional valve.

Seabuckthorn (Hippophae rhamnoides L.) has been used to treat high altitude diseases. The effects of five-week treatment with total flavonoids of seabuckthorn (35, 70, 140 mg/kg, ig) on cobalt chloride (5.5 mg/kg, ip)- and hypobaric chamber (simulating 5,000 m)-induced high-altitude polycythemia in rats were measured. Total flavonoids decreased red blood cell number, hemoglobin, hematocrit, mean corpuscular hemoglobin levels, span of red blood cell electrophoretic mobility, aggregation index of red blood cell, plasma viscosity, whole blood viscosity, and increased deformation index of red blood cell, erythropoietin level in serum. Total flavonoids increased pH, pO2, SpO2, pCO2 levels in arterial blood, and increased Na+, HCO3−, Cl−, but decreased K+ concentrations. Total flavonoids increased mean arterial pressure, left ventricular systolic pressure, end-diastolic pressure, maximal rate of rise and decrease, decreased heart rate and protected right ventricle morphology. Changes in hemodynamic, hematologic parameters, and erythropoietin content suggest that administration of total flavonoids from seabuckthorn may be useful in the prevention of high altitude polycythaemia in rats.

This paper deals with the extraction of L-Theanine containing Aliquat 336 as a carrier and cyclohexane as solvent across bulk liquid membrane. The optimum operation condition are as follows: extraction time of 150 min, initial concentration of theanine in the feed phase is 1.8 g/L, the carrier concentration is 0.5 M, the ion of the receiving phase is 0.2 M NaCl of Na2HPO4-NaH2PO4 buffer solution. A mathematical model of transport process was deduced, the forward interfacial reaction rate constants and the backward interfacial reaction rate constants between the feed phase and the membrane phase, the receiving phase and the membrane phase were taken into account in the model equations. Using the experimental results, several parameters of the proposed model have been achieved by a nonlinear fitting method.

The molecular structure of the title molecule, C12H8BrN3Se, is built up from fused selenazolo and pyridine rings, linked to a 2-bromoaniline group. In the crystal, pairs of molecules are linked by N—H...N hydrogen bonds into dimers, forming eight-membered ring motifs.

The article in Angewandte Chemie discusses the use of copper-based metal-organic frameworks to create highly selective catalysts for the electroreduction of carbon dioxide to ethanol. Researchers found that the electrochemical reduction of unstable Cu coordination centers led to the formation of dispersed Cu subnanoclusters, which promoted the coupling of *CO molecules to generate *CH2CHO species, resulting in efficient CO2-to-EtOH conversion. The study, conducted by Jin Huang et al., highlights the potential of these catalysts for sustainable ethanol production. [Extracted from the article]

The article in the journal "Angewandte Chemie International Edition" discusses the use of copper-based metal-organic frameworks to create highly dispersed Cu subnanoclusters for electrocatalytic CO2-to-EtOH conversion. Researchers, including Jin Huang et al., found that the Cu subnanoclusters promote *CO-*CO coupling, leading to the production of *CH2CHO species and excellent ethanol generation. The study highlights the potential of metal-organic framework supported low-nuclearity cluster catalysts for selective carbon dioxide electroreduction. [Extracted from the article]

This investigation focuses on the phase structures, dielectric, ferroelectric and piezoelectric performances of (1−x)BiFe0.97Ga0.03O3–xBaTiO3 (x, 0.24–0.38) ceramics. A phase transition from rhombohedral to pseudocubic phase was identified as x increases. The morphotropic phase boundary (MPB) of rhombohedral–pseudocubic phase coexistence locates in a broad range of 0.26 ≤x ≤ 0.33. Particularly, both piezoelectric and ferroelectric performances of the materials near MPB were improved. For instance, high remanent polarization Pr of 23.3 μC/cm2 and piezoelectric coefficient d33 up to 173 pC/N were observed for 0.68BiFe0.97Ga0.03O3–0.32BaTiO3 ceramics. Furthermore, the ceramics near MPB has higher Curie temperature than that of the conventional Pb-based piezoceramics. [ABSTRACT FROM AUTHOR]

This work focuses on the effects of Bi compensation on the phase structure, microstructure, ferroelectric, and piezoelectric performances of new 0.69Bi1 + xFeO3-0.31BaTiO3 (x, 0–0.08) piezoceramics fabricated by traditional sintering techniques. X-ray diffraction (XRD) results indicated that Bi compensation has slight influences on the phase structure and all the ceramics locate near the morphotropic phase boundary of rhombehedral–pseudocubic phase coexistence. The rhombehedral phase fraction of all the ceramics fluctuates slightly in the range of 41.7–49.1 %. X-ray photoelectron spectroscopy (XPS) results confirmed that Bi compensation favors the decrease in the percentage of oxygen vacancy in the ceramics. An appropriate content of Bi compensation facilitates the densification, grain growth as well as enhancement of piezoelectric property of the materials. In addition, Bi compensation makes the materials "soft" along with the lower EC compared with the no compensation ceramics. Significantly, the excellent piezoelectric performance (d33 = 207 pC/N) was achieved in the 0.69Bi1.04FeO3-0.31BaTiO3 ceramics, which is higher than the results obtained in the previously reported BiFeO3-BaTiO3-based ceramics. This work would trigger further study on the BiFeO3-BaTiO3-based piezoceramics for practical application. [ABSTRACT FROM AUTHOR]

Abstract We report a case of continued twitching of the latissimus dorsi muscle following breast conservation therapy, along with immediate reconstruction with a latissimus dorsi miniflap, which continued despite several attempts at control including BTX-A percutaneous local injection, and was finally cured by delayed division of the thoracodorsal nerve via a small well-tolerated axillary incision.