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Chinese Journal of Aeronautics 2024年第10期37卷 275-293页

作者： Qi yu Wanchun CHEN Wenbin yu School of Astronautics Beihang UniversityBeijing 102206China

In the scenario that a solid-fuel launch vehicle maneuvers in outer space at hig. ang.es of attack and sideslip for energ. manag.ment,Approximate Analytical Solutions(AAS)for the threedimensional(3D)ascent flig.t states are derived,which are the only solutions capable of considering.time-varying.Mass Flow Rate(MFR)at *** uneven MFR makes the thrust vary nonlinearly and thus increases the difficulty of the problem *** AAS are derived based on a 3D g.neralized Ascent Dynamics Model(g.DM)with a normalized mass as the independent *** simplify some hig.ly nonlinear terms in the g.DM,several approximate functions are introduced carefully,while the errors of the approximations relative to the orig.nal terms are reg.rded as minor ***,a finite series with positive and neg.tive exponents,called Exponent-Symmetry Series(ESS),is proposed for function approximation to decrease the hig.est exponent in the AAS so as to reduce computer round-off *** calculate the ESS coefficients,a method of seeking.the Optimal Interpolation Points(OIP)is proposed using.the leastsquares-approximation *** to the artful desig. of the approximations,the g.DM can be decomposed into two analytically solvable subsystems by a perturbation method,and thus the AAS are obtained ***,to help implement the AAS,two indirect methods for measuring.the remaining.mass and predicting.the burnout time in flig.t are put forward using.information from *** results verify the superiority of the AAS under the condition of time-varying.MFR.

关键词： Approximate analytical solutions 3D ascent trajectory Solid-fuel launch vehicle Uneven thrust Energ. manag.ment

Low-melting.mixture solvents: extension of deep eutectic solvents and ionic liquids for broadening.g.een solvents and g.een chemistry

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g.een Chemical Eng.neering 2024年第4期5卷 409-417页

作者： yu Chen Zhiwu yu MOE Key Laboratory of Bioorg.nic Phosphorous Chemistry and Chemical Biolog. Department of ChemistryTsinghua University

g.een solvents such as water and ionic liquids(ILs) are pillars of the g.eat mansion of g.een chemistry and g.een processing. Initially proposed as a new family of ILs,deep eutectic solvents(DESs) have received fast development in the past two decades. In this contribution,DESs are reviewed critically and the concept is extended to lowmelting.mixture solvents(Lo MMSs),which cover all kinds of materials including.ionic compounds,molecular compounds,and metals. Six classes of Lo MMSs are proposed as the new classification system and examples are g.ven. Finally,several thermodynamic issues concerning.Lo MMSs are discussed. Two new concepts,robustness of Lo MMSs and hig.-entropy Lo MMSs,are proposed.

关键词： g.een solvents Deep eutectic solvents Low transition temperature mixture solvents Phase diag.am Eg.In

Topolog.cal Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,Eng.ish Series 2024年第4期40卷 962-984页

作者： yu ZHANg.yu Jun ZHU School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including.shadowing.property,expansiveness,topolog.cal stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neig.borhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing.property,and moreover,if f is an expanding.endomorphism then there exists a C^(1)-neig.borhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing.property;(2)when a set-valued map F is g.nerated by finite expanding.endomorphisms,it has the shadowing.property,and moreover,if the collection of the g.nerators has no coincidence point then F is expansive and hence is topolog.cally stable;(3)if f is an expanding.endomorphism then for eachε>0 there exists a C^(1)-neig.borhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is g.nerated by finite expanding.endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topolog.cal stability entropy

Laser Diode Pumping.Hig.-stability 1047 nm TEM00 Mode CW Nd: YLiF4 Laser

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Chinese Journal of Lasers 2000年第2期B9卷 103-106页

作者： H. Y. Shen R. F. Wu Z. D. Zeng.W. X. Lin R. R. Zeng.Y. P. Zhou g. F. yu C. H. Huang.(Fujian Institute of Research on the Structure of Matter, Fuzhou 350002, China ) Fujian Institute of Research on the Structure of Matter Fuzhou 350002 China

A laser diode （LD） pumping.hig.-stability 1047 nm TEM00mode Nd: YLiF4（Nd: YLF） continuous wave （CW） laser is reported in this letter. The laser output power of 5. 83 W with optical to optical efficiency of 27 % and slope efficiency of 30 % has been achieved. The instability of output power is 0. 36% and spike caused by relaxation oscillation has not been observed in the laser beam. The transverse cross section of laser beam is an ellipse, the diameters of laser beam at output mirror in both directions are 0. 97 mm and 1. 07 mm, respectively. The diverg.nt ang.es are 0. 936 mrad and 0. 774 mrad, and the values of M2are 1. 37 and 1. 24, respectively. The polarization deg.ee of laser beam is better than 237: 1.

关键词： Nd:YLIF4 laser LD pump CW laser

A new liquid membrane diffusion model for characterizing.the adsorption kinetics of europium by using.a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-Qi yu Tao yu Jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Cg. Cang.an Nuclear Power Co. Ltd.Cangnan 325800China Jiang.i Province Key Laboratory of Polymer Micro/Nano Manufacturing.and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Eng.neering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integ.ation of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding.kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchang. resin were performed using.the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting.the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using.*** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, sug.esting.that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

Exclusive enteral nutrition for treating.pediatric Crohn’s disease

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World Journal of Pediatrics 2024年第9期20卷 869-871页

作者： yu yu Jie Chen Department of g.stroenterolog. Children’s HospitalNational Clinical Research Center for Child HealthZhejiang University School of MedicineHangzhou 310052China

Crohn's disease(CD),an enduring.and relapsing.condition afecting.the g.strointestinal tract,manifests in a spectrum of symptoms and clinical manifestations that can profoundly afect quality of life[1].Recently,CD has emerg.d as a g.obal burden of *** China,the prevalence and incidence of childhood infammatory bowel disease(IBD)have steadily increased,from 0.5 per 1 million in 2001 to 6.0 per 1 million in 2010[2].Pediatric patients often face a long.r treatment duration than adults.

关键词： Crohn pediatric nutrition

Device desig. principles and bioelectronic applications for flexible org.nic electrochemical transistors

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International Journal of Extreme Manufacturing 2024年第1期6卷 126-153页

作者： Lin g.o Meng.e Wu Xing. yu Junsheng.yu State Key Laboratory of Electronic Thin Films and Integ.ated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China(UESTC)Chengdu 610054People’s Republic of China Department of Biomedical Eng.neering City University of Hong KongHong Kong Special Administrative Region of ChinaPeople’s Republic of China

Org.nic electrochemical transistors(OECTs) exhibit sig.ificant potential for applications in healthcare and human-machine interfaces, due to their tunable synthesis, facile deposition, and excellent biocompatibility. Expanding.OECTs to the fexible devices will sig.ificantly facilitate stable contact with the skin and enable more possible bioelectronic applications. In this work,we summarize the device physics of fexible OECTs, aiming.to offer a foundational understanding.and g.idelines for material selection and device architecture. Particular attention is paid to the advanced manufacturing.approaches, including.photolithog.aphy and printing.techniques, which establish a robust foundation for the commercialization and larg.-scale fabrication. And abundantly demonstrated examples rang.ng.from biosensors, artificial synapses/neurons, to bioinspired nervous systems are summarized to hig.lig.t the considerable prospects of smart healthcare. In the end, the challeng.s and opportunities are proposed for fexible OECTs. The purpose of this review is not only to elaborate on the basic desig. principles of fexible OECTs, but also to act as a roadmap for further exploration of wearable OECTs in advanced bio-applications.

关键词： flexible org.nic electrochemical transistors wearable bioelectronics manufacturing.approaches device physics neuromorphic applications

A g.idance and control desig. with reduced information for a dual-spin stabilized projectile

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Defence Technolog.（防务技术） 2024年第3期33卷 494-505页

作者： yu Wang.Jiyan yu Xiaoming.Wang.Jia Fang.iu Intellig.nt Ammunition Technolog. National Defense Key Discipline Laboratory Nanjing University of Science and TechnologyNanjingJiangsu210094China

In this paper,an integ.ated g.idance and control method based on an adaptive path-following.controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system *** to the fairly hig. rotation speed,the dynamic model of this missile is strong.y nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling.of pitch and *** response to the strong.nonlinear and time-varying.characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the seg.entation points in the trajectory envelope,is used for calculation in each *** cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according.to the test ballistic *** order to improve the tracking.efficiency and ensure the tracking.error converg.nce with only translational motion information,the virtual g.ide point,whose derivative is deduced according.to the Lyapunov principle,is calculated in real time according.to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sig.t ang.e and the backstepping.method are used for the desig. of the g.idance and control *** order to avoid the influence of control input saturation on the g.idance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is desig.ed according.to the two-step *** feasibility and effectiveness of the path-following.controller is verified throug. closed-loop flig.t simulations with measurement,control,and condition *** result

关键词： Spin-stabilized projectile Reduced information Path-following.control Extended state observer Coupled nonlinear system Input saturation

A Note on the Entropy for Heisenberg.g.oup Actions on the Torus

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Acta Mathematica Sinica,Eng.ish Series 2024年第10期40卷 2324-2336页

作者： yu ZHANg.yu Jun ZHU School of Mathematical Sciences Xiamen University

In this paper,the entropy of discrete Heisenberg.g.oup actions is *** α be a discrete Heisenberg.g.oup action on a compact metric space *** types of entropies,■ and h(α)are introduced,in which ■ is defined in Ruelle’s way and h(α) is defined via the natural extension of α.It is shown that when X is the torus and α is induced by integ.r matrices then ■ is zero and h(α) can be expressed via the eig.nvalues of the matrices.

关键词： Entropy Heisenberg.g.oup action natural extension torus

Silicon dioxide-protection boosting.the peroxidase-like activity of Fe sing.e-atom catalyst for combining.chemo-photothermal therapy

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Nano Research 2024年第6期17卷 4924-4933页

作者： yu Fan yu Yi Hong.an Rong.Jiatao Zhang Beijing.Key Laboratory of Construction-Tailorable Advanced Functional Materials and g.een Applications School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China CAS Center for Excellence in Nanoscience CAS KeyLaboratory for Biomedical Effects of Nanomaterials and NanosafetyNational Center for Nanoscience and Technology(NCNST)Beijing 100190China Key Laboratory of Medical Molecule Science and Pharmaceutics Eng.neering Ministry of Industry and Information TechnologySchool of Chemistry&Chemical EngineeringBeijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green ApplicationsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Carbon-based sing.e-atom catalysts(SACs)have been widely studied in the field of biomedicine due to their excellent catalytic ***,carbon-based SACs usually ag.reg.te during.pyrolysis,which leads to the reduction of catalytic ***,we describe a method to improve the monodispersion of SACs using.silicon dioxide as a protective *** decoration of silicon dioxide serves as a buffer layer for individual nanoparticles,which is not destroyed during.the pyrolysis process,ensuring.the sing.e-particle dispersion of the nanoparticles after *** approach increased the hydroxyl g.oups on the surface of Fe-SAC(Fe-SAC-SE)and improved its water solubility,resulting.in a four times enhancement of the peroxidase(POD)-like activity of Fe-SAC-SE(58.4 U/mg.than that of non-protected SACs(13.9 U/mg..The SiO_(2)-protection approach could also improve the catalytic activities of SACs with other metals such as Mn,Co,Ni,and Cu,indicating.its g.nerality for SACs *** advantag. of the hig. POD-like activity,photothermal properties,and larg. specific surface area of Fe-SAC-SE,we constructed a synerg.stic therapeutic system(Fe-SAC-SE@DOX@PEg.for combining.the photothermal therapy,catalytic therapy,and *** was verified that the photothermal properties of Fe-SAC-SE@DOX@PEg.could effectively improve its POD-like activity,exhibiting.excellent tumor-killing.performance at the cellular *** work may provide a g.neral approach to improve the performances of SACs for disease therapy and diag.osis.

关键词： sing.e-atom catalysts peroxidase-like activity SiO2-protection photothermal therapy catalytic therapy chemotherapy