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A low-melting-point metal doping strategy for the synthesis of small-sized intermetallic Pt5Ce fuel cell catalysts

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Nano Research 2024年第9期17卷 8112-8118页

作者： Zi-Jun Zou shi-Yi Yin Yao Tang Sheng-liang Zhong Lei Wang shi-Long Xu Hai-Wei liang College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Department of Chemistry University of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China

Carbon-supported platinum-lanthanum(Pt-Ln)intermetallic compound(IMC)nanoparticles with high activity and robust stability have been demonstrated as promising cathode catalysts for proton-exchange membrane fuel ***,the preparation of Pt-Ln IMC catalysts needs high-temperature annealing treatment that inevitably causes nanoparticle sintering,resulting in significant reduction of the electrochemical surface area and mass-based ***,we prepare small-sized M-doped Pt5Ce(M=ga,Cd,and Sb)IMCs catalysts via a low-melting-point metal doping *** speculate that the doping of low-melting-point metals can facilitate the generation of vacancies in the crystal lattice through thermal activation and thus reduce the kinetic barriers for the formation of intermetallic Pt5Ce *** prepared ga-doped Pt5Ce catalyst exhibits a higher electrochemical active surface area(81 m^(2)·gPt^(-1))and a larger mass activity(0.45 A·mgPt^(-1)at 0.9 V)over the undoped Pt5Ce and commercial Pt/C *** the membrane electrode assembly test,the ga-doped Pt5Ce cathode delivers a power density of 0.98 W·cm^(-2)at 0.67 V,along with a voltage loss of only 27 mV at 0.8 A·cm^(-2)at the end of accelerated stability test.

关键词： P5Ce low-melting-point metal small-sized intermetallic compound catalysis fuel cells

Chord length sampling correction analysis for dispersion fuel in Monte Carlo simulation

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Nuclear Science and Techniques 2024年第4期35卷 57-64页

作者： Zhao-Yu liang Ding She Yu-Tong Wen Lei shi Institute of Nuclear and New Energy Technology(INET) Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China

Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled *** with deterministic methods,the Monte Carlo method has more advantages in the geometric modeling of stochastic *** explicit modeling method has high computational accuracy and high computational *** chord length sampling(CLS)method can improve computational efficiency by sampling the chord length during neutron transport using the matrix chord length?s probability density *** study shows that the excluded-volume effect in realistic stochastic media can introduce certain deviations into the CLS.A chord length correction approach is proposed to obtain the chord length correction factor by developing the Particle code based on equivalent transmission *** numerical analysis against reference solutions from explicit modeling in the RMC code,it was demonstrated that CLS with the proposed correction method provides good accuracy for addressing the excludedvolume effect in realistic infinite stochastic media.

关键词： Stochastic media Monte Carlo Chord length sampling Excluded-volume effect Chord length correction

An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming liang guangning Li Min Xu Junmin Zhao fe.g Hao Hongbo shi Northwestern Polytechnical University School of Astronautics Xi’an 710072China China North Industries group Corporation No 203 Research Institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is *** proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application ***,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is *** order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried *** simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight ***,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy *** intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight *** with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability *** intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid

Construction and properties of venlafaxine hydrochloride sustained release system based on hollow mesoporous silica microspheres

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Particuology 2024年第3期86卷 205-210页

作者： Chenjing liang Lingling shi Zhengguo Chen Lan Zhou Zhaoxia Zhang guoqing Zhang School of Materials Science and Engineering Zhejiang Sci-tech UniversityHangzhouChina College of Textile Science and Engineering Zhejiang Sci-tech UniversityHangzhouChina Zhejiang Provincial Innovation Center of Advanced Textile Technology ShaoxingChina

The aim of this work is to develop a venlafaxine hydrochloride sustained release system based on hollow mesoporous silica microspheres(HMSMs).HMSMs were innovatively prepared with tetraethyl silicate(TEOS)as the precursor and volatile n-heptane as a soft *** obtained HMSMs show a well-defined hollow structure with an average size of 967 nm and pore volume of 0.85 cm^(3)/g,implying it is a potential drug ***,venlafaxine hydrochloride(VF)was absorbed in the HMSMs with a content of 37.67% or *** sustained release effect is further measured by the dissolution in-strument at 37℃ and 50 rpm in ultrapure *** results showed that the HMSMs/VF system shows good sustained release properties compared with sustained release tablets with hydroxypropyl meth-ylcellulose as the main *** HMSMs sustained release system appears to be a promising candidate for a sustained drug release.

关键词： Hollowmesoporous silica microspheres(HMSMs) Venlafaxine hydrochloride Drug loading Sustained release

Nano-Au-decorated hierarchical porous cobalt sulfide derived from ZIF-67 toward optimized oxygen evolution catalysis:Important roles of microstructures and electronic modulation

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Carbon Energy 2024年第5期6卷 1-14页

作者： Hongyu gong guanliang Sun Wenhua shi Dongwei Li Xiangjun Zheng Huan shi Xiu liang Ruizhi Yang Changzhou Yuan Department of New Energy Materials School of Environmental and Chemical EngineeringJiangsu University of Science and TechnologyZhenjiangJiangsuChina Advanced Materials Institute Qilu University of Technology(Shandong Academy of Sciences)JinanShandongChina Shandong Saikesaisi Hydrogen Energy Co. Ltd.JinanShandongChina Department of Materials Science and Engineering School of Materials Science&EngineeringUniversity of JinanJinanShandongChina Department of New Energy Science and Engineering College of EnergySoochow Institute for Energy and Materials InnovationsSoochow UniversitySuzhouJiangsuChina

Enhancing both the number of active sites available and the intrinsic activity of Co-based electrocatalysts simultaneously is a desirable ***,a ZIF-67-derived hierarchical porous cobalt sulfide decorated by Au nanoparticles(NPs)(denoted as HP-Au@CoxSy@ZIF-67)hybrid is synthesized by low-temperature sulfuration *** well-defined macroporous-mesoporous-microporous structure is obtained based on the combination of polystyrene spheres,as-formed CoxSy nanosheets,and ZIF-67 *** novel three-dimensional hierarchical structure significantly enlarges the three-phase interfaces,accelerating the mass transfer and exposing the active centers for oxygen evolution *** electronic structure of Co is modulated by Au through charge transfer,and a series of experiments,together with theoretical analysis,is performed to ascertain the electronic modulation of Co by ***,HP-Au@CoxSy@ZIF-67 catalysts with different amounts of Au were synthesized,wherein Au and NaBH4 reductant result in an interesting“competition effect”to regulate the relative ratio of Co^(2+)/Co^(3+),and moderate Au assists the electrochemical performance to reach the highest ***,the optimized HP-Au@CoxSy@ZIF-67 exhibits a low overpotential of 340 mV at 10 mA cm^(-2)and a Tafel slope of 42 mV dec-1 for OER in 0.1 M aqueous KOH,enabling efficient water splitting and Zn-air battery *** work here highlights the pivotal roles of both microstructural and electronic modulation in enhancing electrocatalytic activity and presents a feasible strategy for designing and optimizing advanced electrocatalysts.

关键词： Au nanoparticles cobalt sulfide electronic modulation hierarchical porous structure oxygen evolution reaction

Magnetic Fields Reduce Apoptosis by Suppressing Phase Separation of Tau-441

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Research 2024年第1期2023卷 181-197页

作者： Wen-Juan Lin Wen-Pu shi Wan-Yi ge liang-liang Chen Wei-Hong guo Peng Shang Da-Chuan Yin Key Laboratory for Space Bioscience and Biotechnology School of Life SciencesNorthwestern Polytechnical University127 Youyixi RoadXi'an 710072ShaanxiPR China

The biological effects of magnetic fields(MFs)have been a controversial ***,in recent years,there has been increasing evidence that MFs do affect biological ***,the physical mechanism remains ***,we show that MFs(16 T)reduce apoptosis in cell lines by inhibiting liquid–liquid phase separation(LLPS)of Tau-441,suggesting that the MF effect on LLPS may be one of the mechanisms for understanding the“mysterious”magnetobiological *** LLPS of Tau-441 occurred in the cytoplasm after induction with *** phase-separated droplets of Tau-441 recruited hexokinase(HK),resulting in a decrease in the amount of free HK in the *** cells,HK and Bax compete to bind to the voltage-dependent anion channel(VDAC I)on the mitochondrial membrane.A decrease in the number of free HK molecules increased the chance of Bax binding to VDAC I,leading to increased Bax-mediated *** the presence of a static MF,LLPS was marked inhibited and HK recruitment was reduced,resulting in an increased probability of HK binding to VDAC I and a decreased probability of Bax binding to VDAC I,thus reducing Bax-mediated *** findings revealed a new physical mechanism for understanding magnetobiological effects from the perspective of *** addition,these results show the potential applications of physical environments,such as MFs in this study,in the treatment of LLPS-related diseases.

关键词： inhibited Apoptosis finding

Advances of high-performance LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathode materials and their precursor particles via co-precipitation process

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Particuology 2024年第3期86卷 67-85页

作者： Wenbiao liang Yin Zhao Liyi shi Zhuyi Wang Yi Wang Meihong Zhang Shuai Yuan School of Materials Science and Engineering Shanghai UniversityShanghai200444China Research Center of Nanoscience and Nanotechnology Shanghai UniversityShanghai200444China Emerging Industries Institute Shanghai UniversityJiaxingZhejiang314006China

Layered LiNi_(1-x-y)Co_(x)M_(y)O_(2)(M=Mn or Al)is a promising cathode material for lithium-ion batteries due to its high specific capacity and acceptable manufacturing ***,the polycrystalline LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathode material suffers from disordered orientation of primary particles and poor geometric symmetry of secondary particles,which severely hampers the migration of Lit ***,the resulting anisotropy accelerates the disintegration of the secondary particle structure,significantly affecting the electrochemical performance of the polycrystalline *** spite of less grain boundary,the single-crystal LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathodes still suffer from severe microcracks generated by repeated planar gliding during cycling,which poses a great challenge to the cycling stability of single-crystal ***'s worth noting that the microstructure of the cathode material is mainly inherited from its ***,it is necessary to deeply understand the influence of the microstructure of Ni_(1-x-y)Co_(x)M_(y)(OH)2 on the electrochemical properties of LiNi_(1-x-y)Co_(x)M_(y)O_(2) cathode materials,so as to optimize the production process of preparing high-performance cathode *** this review,we summarize recent advances in the research and development of Ni-rich cathode precursor ***,the challenges faced by the Ni-rich hydroxide precursor materials are presented,including the effect of primary particle morphology and arrangement on the electrochemical performance of cathode materials,the influence of secondary particle morphology on lithium insertion reactions in cathode,and the effect of particle size on the microcracking of single-crystal ***,the presentation of the conventional co-precipitation reactor,the mechanism of precursor particle growth,and the influence of coprecipitation parameters are described in ***,the strategies are systematically discussed to solve the cha

关键词： Lithium-ion batteries Cathode materials Co-precipitation Ni-rich layered oxides Single crystal Precursor particles

Research on gait Trajectory Planning of Wall-Climbing Robot Based on Improved PSO Algorithm

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Journal of Bionic Engineering 2024年第4期21卷 1747-1760页

作者： Jian Li Xianlin shi Peng liang Yanjun Li Yilin Lv Mingyue Zhong Zezhong Han School of Mechanical and Automotive Engineering Guangxi University of Science and TechnologyLiuzhou545006China

In order to reduce the labor intensity of high-altitude workers and realize the cleaning and maintenance of high-rise building exteriors,this paper proposes a design for a 4-DOF bipedal wall-climbing bionic robot inspired by the inchworm’s *** robot utilizes vacuum adsorption for vertical wall attachment and legged movement for *** enhance the robot’s movement efficiency and reduce wear on the adsorption device,a gait mimicking an inchworm’s movement is planned,and foot trajectory planning is performed using a quintic polynomial *** velocity constraints,foot trajectory optimization is achieved using an improved Particle Swarm Optimization(PSO)algorithm,determining the quintic polynomial function with the best fitness through ***,through comparative experiments,the climbing time of the robot closely matches the simulation results,validating the trajectory planning method’s accuracy.

关键词： Bionic robot Wall-climbing robot PSO gait planning Trajectory planning

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan Qi Xin Zhang Jun Li Dong-liang Zhao shi-hai guo Yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy