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Leaching improvement of ceramic cores for hollow turbine blades based on additive manufacturing

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Advances in Manufacturing 2019年第4期7卷 353-363页

作者： wei-Jun Zhu Guo-Qiang Tian Yang Lu Kai Miao di-chen Li School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191People's Republic of China State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong UniversityXi'an 710049People's Republic of China School of Aeronautical Engineering Zhengzhou University of AeronauticsZhengzhou 450046People's Republic of China

The precision casting method based on aluminabased ceramic cores is one of the main techniques used to manufacture hollow turbine *** manufacturing(AM)technology provides an alternate solution to fabricating ceramic cores quickly and *** the complexity of the structure increases and the strength of the material improves,the leaching process of the cores becomes more *** study proposes a compound pore-forming method to increase the porosity of ceramic cores by adding a preformed-pore agent and materials that convert to easy-to-corrode *** preformed-pore agents(e.g.,carbon fibers)can be burned off during sintering to form pores before the leaching,and the easy-to-corrode phases(e.g.,CaCO3,SiO2,^-A12O3)can be leached firstly to form pores during the leaching *** pores formed in the aforementioned two stages increase the contact area of the cores and leaching solution,thus improving the leaching *** the current study,the additive amount of the preformed-pore agent was optimized,and the effect of the easy-to-corrode phases on the comprehensive properties of the cores was then *** on this,the corresponding model was established.

关键词： Alumina-based ceramic core Leaching Alkali solution Additive manufacturing(AM) Stereolithography

Heat treatment bimetallic PdAu nanocatalyst for oxygen reduction reaction

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Journal of Energy Chemistry 2020年第1期29卷 217-223,I0008页

作者： Qingyun Hu wei Zhan Yifei Guo Laiming Luo Ronghua Zhang di chen Xinwen Zhou College of Biological and Pharmaceutical Science China Three Gorges University

Pd-based nanocatalyst is a potential oxygen reduction oxidation(ORR)catalyst because of its high activity in alkaline medium and low *** this work,bimetallic Pd Au nanocatalysts are prepared by one-pot hydrothermal method using triblock pluronic copolymers,poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)(PEO19-PPO69-PEO19)(P123)as reducer and stabilizer,and heat-treatment method is applied to regulate catalyst structure and improve catalyst *** results show that the heat treatment can agglomerate the catalyst to a certain extent,but effectively improve the crystallinity and alloying degree of the *** ORR performance of the Pd Au nanocatalysts obtained under different heat treatment conditions is systematically *** with commercial Pd black and Pd Au catalyst before heat treatment,the ORR performance of Au Pd nanocatalyst obtained after heat treatment for one hour at 500℃ has been *** Pd Au nanocatalysts after heat treatment also display enhanced anti-methanol toxicity ability in acidic medium.

关键词： PdAu catalysts Nanochain Heat treatment Oxygen reduction reaction Anti-methanol oxidation

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Environmental characteristics of trace metals in seawater from the Ninety East Ridge in the Indian Ocean

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Journal of Oceanology and Limnology 2024年第4期42卷 1119-1129页

作者： Jingxi LI di ZHANG Fenghua JIANG Hong chen wei CAO chengjun SUN Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China Laoshan Laboratory of Marine Science and Technology Laboratory of Marine Drugs and Biological ProductsQingdao 266071China

The Ninety East Ridge in the Indian Ocean has complex and unique *** concentrations and distribution characteristics of 10 trace metals(V,Cr,Mn,Fe,Co,Ni,Cu,Cd,Pb,and U)in seawater from the Ninety East Ridge in the Indian Ocean were *** show that the average concentrations of different trace metals in all the collected seawater samples were 1.134μg/L for V,0.158μg/L for Cr,0.489μg/L for Mn,0.427μg/L for Fe,0.011μg/L for Co,0.395μg/L for Ni,0.403μg/L for Cu,0.097μg/L for Cd,0.139μg/L for Pb,and 3.470μg/L for *** in the horizontal and vertical distributions of all measured trace metals were revealed,and the occurrence of high concentrations was *** addition,the significant differences in the concentration distribution of different trace metals in seawater on both sides of the Ninety East Ridge present regional segmentation in the area for various trace metals in deep sea *** study provided basic data for future investigations on the environmental and ecological impact of trace metals in the Indian Ocean and the potential water mass transport mechanism.

关键词： trace metal environmental characteristic Ninety East Ridge seawater Indian Ocean

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新型二维声子晶体带隙特性及调控方法研究

大连理工大学学报 2025年第1期65卷 48-55页

作者：胡启国胡皓魏晨胡豁然重庆交通大学机电与车辆工程学院重庆400074 国网重庆市电力公司信息通信分公司重庆401120

为拓宽声子晶体弹性波带隙,提出一种关于基体双侧对称的声子晶体结构模型.采用有限元法计算了该声子晶体的能带结构和本征模态,基于局域共振机理深入分析了其带隙的形成机理,通过改变几何参数及施加等轴预拉伸应变的方法对该声子晶体的... 详细信息

为拓宽声子晶体弹性波带隙,提出一种关于基体双侧对称的声子晶体结构模型.采用有限元法计算了该声子晶体的能带结构和本征模态,基于局域共振机理深入分析了其带隙的形成机理,通过改变几何参数及施加等轴预拉伸应变的方法对该声子晶体的带隙进行被动调控与主动调控.仿真结果表明:所提声子晶体结构基体中的长波行波与振子的谐振相互耦合作用产生一条局域共振带隙,通过优化几何参数可以获得起始频率更低的宽频带隙,对结构施加等轴预拉伸应变可以有效拓宽带隙且带隙宽度随着预拉伸应变的增大而变宽.研究结果为声子晶体的带隙主动调控提供了方案,为结构减振降噪提供了新思路.

关键词：声子晶体带隙特性带隙调控预拉伸应变

Aerodynamic Optimization and Flow Mechanism for a Compressor Cascade at Low Reynolds Number

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Journal of Thermal Science 2025年第1期 92-109页

作者： LI Lin ZHANG Jianshe chen Caiyan TAN wei ZHANG Yanfeng Key Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of Sciences University of Chinese Academy of Sciences National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine

Low-Reynolds-number effect is an important factor affecting the performance of compressors and other main components of high-altitude long-endurance unmanned aerial *** improve the flow condition and reduce flow loss under the condition of high altitude and low Reynolds number(Re),this paper proposes an optimization process based on a surrogate model,which combines the class-shape transformation method(CST),the Latin hypercube sampling(LHS) method,the light gradient-boosting machine algorithm(LightGBM),and a genetic algorithm(GA) to optimize a high-subsonic compressor *** surrogate model is verified to be accurate and can be used in the optimization *** accuracy of the GA is higher than the other algorithms under common test *** optimization results are verified by numerical simulation,and the flow differences before and after optimization are compared,especially the flow within the boundary *** changing the blade shape,the optimization process adjusts the loading distribution to delay the transition of the optimized blade on the suction surface,which changes the turbulent reattachment in the laminar separation bubble(LSB) into laminar ***,the mixing loss induced by the turbulent reattachment of the LSB and the wake loss of turbulent separation at the trailing edge are significantly reduced,and the performance of the compressor profile is finally *** addition,turbulent separation of the optimized profile is delayed reducing the range of the wake region on the suction *** this optimization process,the reduction of total pressure loss coefficient at Re of 2.5×10～5,3.5×10～5,and 4.5×10～5 are 16.32%,20.76%,and 22.16%,respectively.

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Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期 206-222页

作者： YANG Jianwen chen wei CAO Bingwei LIU Xinhui LI Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

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One-step post-treatment boosts thermoelectric properties of PEDOT:PSS flexible thin films

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Journal of Materials Science & Technology 2023年第1期132卷 81-89页

作者： Xingyu Liu Xiao-Lei Shi Li Zhang wei-di Liu Yanling Yang Zhi-Gang chen School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China School of Chemistry and Physics Queensland University of TechnologyBrisbaneQLD 4000Australia Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQLD 4072Australia

Developing high-performance poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)sig-nificantly widens the practical applications of flexible organic thermoelectric devices,while the water-based co-solvent dopants and/or post-treatments are still rarely studied so ***,we develop a one-step post-treatment to improve the power factor of PEDOT:PSS films by using a water-based solution,which is composed of co-solvent(polar solvent dimethylacetamide(DMAC)and deionized water)and organic reducing agent L-ascorbic acid(LAA).The 80 vol.%DMAC solution significantly boosts the room-temperature electrical conductivity of the films from 5 to 964 S cm^(−1),while the Seebeck coefficient can be further enhanced from 18.7 to 25μV K−1 by treating with 0.5 mol L−1 LAA,contributing to a sig-nificantly improved power factor of 55.3μW m^(−1)K^(−2).The boosted electrical conductivity is ascribed to the separated PEDOT and PSS phases triggered by the high dielectric constant and polarity of DMAC;while the improved Seebeck coefficient is attributed to the reduced oxidation degree of PEDOT from the reducing agent LAA,both confirmed by the comprehensive structural and morphological ***,a maximum power factor of 64.4μW m^(−1)K^(−2)can be achieved at 360 K and the observed temperature-dependent electrical transport behavior can be well explained by the Mott variable range hopping ***,a flexible thermoelectric device,assembled by the as-fabricated PEDOT:PSS films,exhibits a maximum output power of∼23 nW at a temperature difference of 25 K,indicating the potential for applying to low-grade wearable electronics.

关键词： Thermoelectric PEDOT:PSS Post-treatment dimethylacetamide L-ascorbic acid

Design and Synthesis of 1-Glycosyl-4-{N-[（2＇-morpholinethoxy）- phenyl] aminomethyl}- 1H- 1,2,3-triazoles as Calcium Activators

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Chemical Research in Chinese Universities 2015年第6期31卷 952-957页

作者： LI Yuxin di Fengjuan WANG Duoyi chen wei WAN Yingying LI Zhengming State Key Laboratory of Elemento-Organie Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

A series of novel l-glycosyl-4-{N-[（2＇-morpholinethoxy）phenyl]aminomethyl}-1H-1,2,*** was designed and synthesized through a simple and efficient multistep synthetic method in good yields. The 1,2,3-triazole moiety acted as a single disubstituted ring and a linker between carbohydrates（D-glucose, D-galactose, maltose and lactose） and morpholine. The compounds were characterized by ^1H NMR, ^13C NMR and mass spectra（MS）. Two dif- ferent deprotection methods were discussed. The effects of compounds 5a, 5c and 6e on the intracellular calcium ion concentration（[Ca^2＋]i） in the central neurons of S. exigua were well investigated by calcium imaging technique. The results demonstrated that compound 6e could elevate the calcium concentration in the glial cells, not in the neurons.

关键词： Calcium channel Click chemistry Glial cell Glycosyl Triazole

Thermo-sensitive Poloxamer based antibacterial anti-inflammatory and photothermal conductive multifunctional hydrogel as injectable,in situ curable and adjustable intraocular lens

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Bioactive Materials 2024年第11期41卷 30-45页

作者： chen Qin Fan Fei Youfei wei Yuemei Han di Hu Quankui Lin National Engineering Research Center of Ophthalmology and Optometry School of Biomedical EngineeringSchool of Ophthalmology and OptometryEye HospitalWenzhou Medical UniversityWenzhou325027China

Cataract patients look forwards to fewer postoperative complications and higher vision quality after ***,the current intraocular lens(IOL)implanted after cataract surgery neither can adjust focal length in response to ciliary muscle contraction as natural lens nor have the ability to prevent postoperative ***,a thermosensitve Poloxamer based hybrid hydrogel with antibacterial anti-inflammatory and photothermal functional elements doping was designed and used as injectable,in situ curable,and adjustable IOL(FHTAB IOL).The FHTAB IOL was composed of thermosensitve triblock-polymer F127DA and a small amount of HAMA,combined with BP NS,TA,and Ag *** IOL can be injected into the empty lens capsule after cataract surgery via an injectable thermos-gel under NIR illumination and then be rapidly cured to form a full-size IOL under short-time blue light *** designed injectable FHTAB IOL possesses high transparency and transmittance,with a refractive index similar to the natural lens and adjustable *** was stabilized as a refractive medium without any leakage in the *** addition,the TA and Ag NPs loaded in the FHTAB IOL displayed significant antibacterial and anti-inflammatory effects in vitro and *** study presents a potentially effective new strategy for the development of multifunctional adjustable IOLs.

关键词： Adjustable IOL Injectable hydrogel Antibacterial Anti-inflammatory