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Numerical simulation of fluid-thermal-structural coupling characteristics of stratospheric non-rigid airship

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Chinese Journal of Aeronautics 2024年第9期37卷 224-236页

作者： Huafei DU Mingyun LYU Chuan YU Yifei wu Yongmei wu Kangwen SUN School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Linzhou(Ningbo)Technology Co.Ltd Yuyao 315042China

The voluminous stratospheric non-rigid airship is very sensitive to the external thermal *** temperature change of internal gas caused by the variation in the external ther-mal environment and wind speed will lead to a change in the shape and buoyancy of the airship,thereby affecting its flight *** traditional static analysis method is difficult to accurately reflect this fuid-thermal-structural coupling *** this paper,the iterative analysis method was established for the fluid-thermal-structural coupling effect of stratospheric non-rigid airship based on the models of fluid,thermal,and structural *** the load such as the internal thermal effect and external flow field of the airship,the simulation of the thermo-induced structural deformation effect was conducted using Fluent and Abaqus *** influ-ence of local time and external wind speed on the structural deformation,volume,and equilibrium altitude of the airship was *** results demonstrate that,at low wind speed,the influence of aerodynamic pressure on the deformation of the airship is ***,a great amount of heat is carried away by the wind,then the structural deformation caused by internal and external pressure difference is alleviated and the equilibrium altitude of the airship change *** can serve as a guideline for the design and flight test of the long-endurance stratospheric non-rigid airship.

关键词： Altitude change Fluid-thermal-structural coupling Stratospheric non-rigid airship Structural deformation Wind speed

Flotation separation of scheelite from calcite using luteolin as a novel depressant

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 462-472页

作者： Xiaokang Li Ying Zhang Haiyang He Yu wu Danyu wu Zhenhao Guan Faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Clean Utilization of Complex Non-Ferrous Metal Resources Kunming University of Science and TechnologyKunming 650093China

This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)*** suitability of LUT as a calcite depressant is confirmed through micro-flotation *** pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two ***,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on *** capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is ***-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions *** directly illustrates the distinct adsorption densities of LUT on the two miner-al ***,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.

关键词： scheelite calcite luteolin flotation depressant separation

Graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks

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Digital Communications and Networks 2024年第1期10卷 45-52页

作者： Pei Li Lingyi Wang Wei wu Fuhui Zhou Baoyun Wang Qihui wu Nanjing University of Posts and Telecommunications Nanjing210023China Nanjing University of Aeronautics and Astronautics Nanjing210016China

In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)*** objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be *** comprehensively considered the interference among D2D communications and downlink *** original problem is strongly non-convex,which requires high computational complexity for traditional optimization *** to make matters worse,the results are not necessarily globally *** this paper,we propose a novel Graph Neural Networks(GNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity ***,we first construct a GNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,***,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of *** results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on ***,it also shows that the performance of proposed GNN-based method is better than that of traditional means.

关键词： Unmanned aerial vehicle D2 Dcommunication Graph neural network Power control Position planning

Cobalt doping amount determines dominant reactive species in peroxymonosulfate activation via porous carbon catalysts co-doped by cobalt and nitrogen

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Journal of Environmental Sciences 2024年第4期138卷 212-226页

作者： Xiang Li Limeng wu Aiqin Zhang Shaohua wu Yan Lin Chunping Yang Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China Academy of Environmental and Resource Sciences School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000China College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China

Switching the reaction routes in peroxymonosulfate(PMS)-based advanced oxidation processes have attracted much attention but remain ***,a series of Co-N/C catalysts with different compositions and structures were prepared by using bimetallic zeolitic imidazolate frameworks based on ZIF-8 and ZIF-67(x Zn/Co-ZIFs).Results show that Co doping amount could mediate the transformation of the activation pathway of PMS over CoN/*** Co doping amount was less than 10%,the constructed x Co-N/C/PMS system(x≤10%)was singlet oxygen-dominated reaction;however further increasing Co doping amount would lead to the generation and coexistence of sulfate radicals and high-valent cobalt,besides singlet ***,the nitrogen-coordinated Co(Co-NX)sites could serve as main catalytically active sites to generate singlet *** excess Co doping amount caused the formation of Co nanoparticles from which leached Co ions were responsible for the generation of sulfate radicals and high-valent *** to undoped N/C,Co doping could significantly enhance the catalytic *** 0.5%Co-N/C could achieve the optimum degradation(0.488 min^(-1))and mineralization abilities(78.4%)of sulfamethoxazole among the investigated Co-N/C catalysts,which was superior to most of previously reported *** addition,the application prospects of the two systems in different environmental scenarios(pH,inorganic anions and natural organic matter)were assessed and showed different degradation *** study provides a strategy to regulate the reactive species in PMS-based advanced oxidation process.

关键词： Peroxymonosulfate Sulfate radical Singlet oxygen Cobalt Zeolitic imidazolate framework Advanced oxidation process

Phase-field lattice-Boltzmann study on fully coupled thermal-solute-convection dendrite growth of Al-Cu alloy

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China Foundry 2024年第2期21卷 125-136页

作者： Yin-qi Qiu Meng-wu wu Xun-peng Qin Shou-mei Xiong Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors.A phase-field lattice-Boltzmann method was developed to simulate the two-and three-dimension dendrite growth of Al-Cu *** effect of fully coupled thermal-solute-convection interaction on the dendrite growth was investigated by incorporating a parallel-adaptive mesh refinement algorithm into the numerical *** accurately reproducing the latent heat release,solute diffusion and convective transport behaviors at the liquidsolid interface,the interaction mechanism among thermal-solute-convection transport as well as their coupling effects on the dendrite growth dynamics were *** simulation results show that the release of latent heat slows down the dendrite growth rate,and both natural and forced convection disrupt the symmetrical growth of *** combination makes the growth of dendrites more complex,capturing important physical aspects such as recalescence,dendrite tip splitting,dendrite tilting,dendrite remelting,and solute plume in the simulation *** on the robustness and powerful ability of the numerical model,the formation mechanisms of these physical aspects were revealed.

关键词： simulation phase field dendrite growth thermal-solute-convection interaction

Functionalized selenium nanoparticles ameliorated acetaminophen-induced hepatotoxicity through synergistically triggering PKCδ/Nrf2 signaling pathway and inhibiting CYP 2E1

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Food Science and Human Wellness 2024年第2期13卷 932-945页

作者： Si Zou Yetao Gong Xiujie Li Yanbin wu Jinzhong wu Jianguo wu Ka-Hing Wong College of Pharmacy Fujian University of Traditional Chinese MedicineFuzhou 350122China Research Institute for Future Food The Hong Kong Polytechnic UniversityHong Kong 999077China Department of Food Science and Nutrition The Hong Kong Polytechnic UniversityHong Kong 999077China

Selenium nanoparticles(SeNPs)have been demonstrated potential for use in diseases associated with oxidative *** SeNPs with lower toxicity and higher biocompatibility could bring better therapeutic activity and clinical application ***,this work was conducted to investigate the protective effect of Pleurotus tuber-regium polysaccharide-protein complex funtionnalized SeNPs(PTR-SeNPs)against acetaminophen(APAP)-induced oxidative injure in HepG2 cells and C57BL/6J mouse *** elucidation of the underlying molecular mechanism,in particular their modulation of Nrf2 signaling pathway was also *** results showed that PTR-SeNPs could significantly ameliorate APAP-induced oxidative injury as evidenced by a range of biochemical analysis,histopathological examination and immunoblotting ***-SeNPs could hosphorylate and activate PKCδ,depress Keap1,and increase nuclear accumulation of Nrf2,resulting in upregulation of GCLC,GCLM,HO-1 and NQO-1 ***,PTR-SeNPs suppressed the biotransformation of APAP to generate intracellular ROS through CYP 2E1 inhibition,restoring the mitochondrial ***,the protective effect of PTR-SeNPs against APAP induced hepatotoxicity was weakened as Nrf2 was depleted in vivo,indicating the pivotal role of Nrf2 signaling pathway in PTR-SeNPs mediated hepatoprotective *** a potential hepatic protectant,PTR-SeNPs could serve as a new source of selenium supplement for health-promoting and biomedical applications.

关键词： PTR-SeNPs(polysaccharide-proteincomplex functionalized selenium nanoparticles) Acetaminophen-induced hepatotoxicity Nuclear factor erythroid 2-related factor 2 Cytochrome P450 enzyme 2E1 Mitochondria

The photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis

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Acta Geochimica 2024年第1期43卷 174-179页

作者： Yanyou wu Shaogang Guo State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Photosynthesis is the most important biochemical reaction on Earth. It has co-evolved and developed with the Earth, driving the biogeochemical cycle of all elements on the planet and serving as the only chemical process in nature that can convert light energy into chemical energy. Some heavy oxygen isotopic(^(18)O) labeling experiments have"conclusively" demonstrated that the oxygen released by photosynthesis comes only from water and are written into textbooks. However, it is not difficult to find that bicarbonate has never been excluded from the direct substrate of photosynthesis from beginning to end during the history of photosynthesis research. No convincing mechanism can be used to explain photosynthetic oxygen evolution solely from water photolysis. The bicarbonate effect, the Dole effect, the thermodynamic convenience of bicarbonate photolysis, the crystal structure characteristics of photosystem Ⅱ, and the reinterpretation of heavy oxygen isotopic labeling(^(18)O)experiments all indicate that the photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis. The recently proposed view that bicarbonate photolysis is the premise of water photolysis, bicarbonate photolysis and water photolysis work together with a 1:1(mol/mol) stoichiometric relationship, and the stoichiometric relationship between oxygen and carbon dioxide released during photosynthetic oxygen evolution is also 1:1, has excellent applicability and objectivity, which can logically and reasonably explain the precise coordination between light and dark reactions during photosynthesis, the bicarbonate effect, the Dole effect, the Kok cycle and the neutrality of water and carbon in *** is of great significance for constructing the bionic artificial photosynthetic reactors and scientifically answering the question of the source of elemental stoichiometric relationships in nature.

关键词： Bicarbonate effect Dole effect Kok cycle Heavy oxygen isotope Artificial photosynthetic reactor

Influence mechanism of government subsidy on the green transformation of coal company in China

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International Journal of Mining Science and Technology 2024年第7期34卷 1033-1040页

作者： Xiaolei Li Changsong wu School of Management China University of Mining and Technology-BeijingBeijing 100083China School of Economics and Management China University of Mining and TechnologyXuzhou 221116China

The optimization of government subsidies to enhance the efficiency of coal companies’green transformation constitutes a critical component in the pursuit of global *** investigate the influence mechanism of government subsidies on the green transformation using data from the listed coal companies in China from 2007 to *** to our findings and hypothesis testing,previous government subsidies did not have a significant direct impact on coal companies’green ***,government subsidies can help coal companies transition to greener practices by promoting innovative green ***,we confirmed an indirect route:that government subsidies enable the adoption of low-carbon initiatives,which in turn could facilitate the transition of coal companies towards green *** addition,we discovered that the coal company’s digitization will improve this indirect ***,we propose increasing the effectiveness of government subsidies in facilitating coal companies’transition to green practices by focusing on technological advancements and enhancing company digitalization.

关键词： Government subsidy Green transformation Coal company Digitalization Innovation

The physiological role of the unfolded protein response in the nervous system

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Neural Regeneration Research 2024年第11期19卷 2411-2420页

作者： Shuangchan wu Wensheng Lin Department of Neuroscience University of MinnesotaMinneapolisMNUSA Institute for Translational Neuroscience University of MinnesotaMinneapolisMNUSA

The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfolded *** UPR aims to restore endoplasmic reticulum homeostasis by enhancing protein folding capacity,reducing protein biosynthesis,and promoting protein *** also plays a pivotal role in coordinating signaling cascades to determine cell fate and function in response to endoplasmic reticulum *** research has highlighted the significance of the UPR not only in maintaining endoplasmic reticulum homeostasis but also in influencing various physiological processes in the nervous ***,we provide an overview of recent findings that underscore the UPR’s involvement in preserving the function and viability of neuronal and myelinating cells under physiological conditions,and highlight the critical role of the UPR in brain development,memory storage,retinal cone development,myelination,and maintenance of myelin thickness.

关键词： myelin neuron oligodendrocyte Schwann cell unfolded protein response