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Status Report of HIAF Ion Source Front-end

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IMP & HIRFL Annual Report 2022年第1期 222-223页

作者： Lu Wang Sun Liangting HIAF Frond-end Project Team 不详

As the injector of the HIAF facility,the Ion Source Front-end system needs to provide intense highly charged heavy ions with mass-charge ratio M/Q=27 and energy e=14 keV/***,the provided heavy ions are required to match the acceptance of the RFQ accelerator in three-dimensional phase *** front-end system consists of two 100 kV high-voltage platforms,three eCR ion sources,and corresponding low-energy transmission beam lines and matching segments.

关键词： system energy intense

Multi-revolution low-thrust trajectory optimization using symplectic methods

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Science China(Technological Sciences) 2020年第3期63卷 506-519页

作者： e ZhiBo GUZZeTTI Davide School of Aerospace engineering Tsinghua UniversityBeijing 100084China Department of Aerospace engineering Auburn UniversityAuburn AL 36849USA

Optimization of low-thrust trajectories that involve a larger number of orbit revolutions is considered as a challenging *** paper describes a high-precision symplectic method and optimization techniques to solve the minimum-energy low-thrust multi-revolution orbit transfer problem. First, the optimal orbit transfer problem is posed as a constrained nonlinear optimal control problem. Then, the constrained nonlinear optimal control problem is converted into an equivalent linear quadratic form near a reference solution. The reference solution is updated iteratively by solving a sequence of linear-quadratic optimal control sub-problems, until convergence. each sub-problem is solved via a symplectic method in discrete form. To facilitate the convergence of the algorithm, the spacecraft dynamics are expressed via modified equinoctial elements. Interpolating the non-singular equinoctial orbital elements and the spacecraft mass between the initial point and end point is proven beneficial to accelerate the convergence process. Numerical examples reveal that the proposed method displays high accuracy and efficiency.

关键词： low-thrust trajectory optimization symplectic method multi-revolution transfers

Aligned carbon nanotubes for lithium-ion batteries:A review

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Nano Research 2023年第11期16卷 12384-12410页

作者： Chinaza e.Nwanno Wenzhi Li Department of Physics Florida International UniversityMiamiFL 33199USA

Nanoscale materials are gaining massive attention in recent years due to their potential to alleviate the present electrochemical electrode *** high conductivity(both thermally and electrically),high chemical and electrochemical stability,exceptional mechanical strength and flexibility,high specific surface area,large charge storage capacity,and excellent ionadsorption,carbon nanotubes(CNTs)remain one of the most researched of other nanoscale materials for electrochemical energy *** than having them packed at random,CNTs perform better when packed/grown to order,vertically or horizontally aligned to a *** study presents an overview of the impact of CNT alignment on the electrochemical performance of lithium-ion batteries(LIBs).The unique properties of vertically aligned CNTs(VACNTs)for LIB application were ***,the mechanisms of charge storage and electrochemical performances in VACNT-based(pristine and composites)anodes and cathodes of LIBs were succinctly *** the end,the existing challenges and future directions in the field were also briefly discussed.

关键词： nanoscale vertically aligned carbon nanotubes(VACNTs) composites lithium-ion batteries(LIBs) anodes cathodes

effect of particle breakage on the behavior of simulated angular particle assemblies

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China Particuology 2007年第5期5卷 328-336页

作者： e. Seyedi Hosseininia A.A. Mirghasemi School of Civil engineering Faculty of EngineeringUniversity of Tehran

Many attempts have been made to find various relationships for different parameters and some kinds of constitutive models for studying the behavior of particulate media. All these models are based on concepts of continuous media. Using a numerical method such as discrete element method, one can figure out what is happening through a discontinuous media where soil particles play the main role in introducing the shear strength and deformation characteristics. The behavior of the media with breakable particles is studied in this paper and compared with that of the assembly with non-breakable particles. In this paper, the hyperbolic elastic model is investigated for the assembly of polygon shaped particles in two different test series. In addition, evolution of different macro parameters of the assembly such as volume strain, angle of friction, angle of dilatancy and elastic modulus is studied during the simulation tests both for non-breakable and breakable soil particles. At the end, a parametric study is performed on the effect of strength of particle breakage on the assembly behavior.

关键词： Discrete element modeling Particle breakage Hyperbolic elastic model Confining pressure

effect of sediment size on bioleaching of heavy metals from contaminated sediments of Izmir Inner Bay

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Journal of environmental Sciences 2013年第9期25卷 1784-1794页

作者： Duyusen e.Guven Gorkem Akinci Dokuz eylul University Faculty of Engineering Department of Environmental EngineeringKaynaklar Campus35160 Buca Izmir Turkey

The effect of sediment size on metals bioleaching from bay sediments was investigated by using fine （〈 45 μm）, medium （45-300 μm）, and coarse （300-2000 μm） size fractions of a sediment sample contaminated with Cr, Cu, Pb, and Zn. Chemical speciation of the metals in bulk and size fractions of sediment were studied before and after bioleaching. Microbial activity was provided with mixed cultures of Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans. The bioleaching process was carried out in flask experiments for 48 days, by using 5% （W/V） of solid concentration in suspension. Bioleaching was found to be efficient for the removal of selected heavy metals from every size fraction of sediments, where the experiments with the smaller particles resulted in the highest solubilization ratios. At the end of the experimental period, Cr, Cu, Pb and Zn were solubilized to the ratios of 68%, 88%, 72%, and 91% from the fine sediment, respectively. Higher removal efficiencies can be explained by the larger surface area provided by the smaller particles. The changes in the chemical forms of metals were determined and most of the metal releases were observed from the reducible and organic fractions independent from grain size. Higher concentrations were monitored in the residual fraction after bioleaching period, suggesting they are trapped in this fraction, and cannot be solubilized under natural conditions.

关键词： sediment sediment size heavy metals bioleaching Acidithiobacillus microbial activity

Outcomes and management of viral hepatitis and human immunodeficiency virus co-infection in liver transplantation

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World Journal of Gastroenterology 2014年第2期20卷 414-424页

作者： Stephen e Congly Karen e Doucette Carla S Coffin Liver Unit Division of Gastroenterology and HepatologyUniversity of CalgaryCalgaryAB T2N 4Z6Canada Division of Infectious Diseases University of AlbertaEdmontonAB T6G 2R3Canada

Liver transplantation for human immunodeficiency virus(HIV)positive patients with viral hepatitis co-infection is increasingly offered in many North American and european liver transplant *** studies have demonstrated acceptable post-transplant outcomes and no increased risk of HIV complications in patients coinfected with hepatitis B virus(HBV).However,liver transplantation in HIV positive patients with hepatitis C virus(HCV)has poorer outcomes overall,requiring careful selection of *** review aims to summarize the published literature on outcomes after transplant in HIV patients with HBV or HCV related end-stage liver disease and recommendations for *** particular the pre-transplant factors impacting outcomes in HCV/HIV co-infected candidates and importance of multidisciplinary management will be discussed.

关键词： Hepatitis B virus Human immunodeficiency virus co-infection Hepatitis C virus Co-infection Liver transplantation

Active disturbance rejection control： Applications in aerospace

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Control Theory and Technology 2018年第4期16卷 314-323页

作者： S. e. TALOLe Department of Aerospace engineering Defence Institute of Advanced Technology Girinagar Pune-411 025 India

Control of uncertain dynamical systems has been an area of active research for the past several decades and to this end, various robust control approaches have been proposed in the literature. The active disturbance rejection control （ADRC） represents one prominent approach that has been widely studied and applied for designing robust controllers in diverse areas of engineering applications. In this work, a brief review of the approach and some of its applications in aerospace are discussed. The results show that the approach possesses immense potential to offer viable solution to real-life aerospace problems.

关键词： Active disturbance rejection control uncertainty and disturbance estimation extended state observer robust control

electronic band energy of a bent ZnO piezoelectric semiconductor nanowire

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Applied Mathematics and Mechanics(english edition) 2020年第6期41卷 833-844页

作者： Wanli YANG Yuantai HU e.N.PAN Department of Mechanics Hubei Key Laboratory of Engineering Structural Analysis and Safety AssessmentHuazhong University of Science and TechnologyWuhan 430074China Computer Modeling and Simulation Group College of EngineeringUniversity of AkronAkronOhio 44325U.S.A.

The electric band energy variation in a bent piezoelectric semiconductor(PSC) nanowire of circular cross-section induced by the mechanical force is analyzed based on a six-band k · p method. The electric-mechanical fields are first obtained analytically in a cantilever bent PSC nanowire by solving the fully-coupled electro-mechanical equations. Then, the band energy is acquired numerically via the six-band *** considering further the nonlinear coupling between the piezoelectric and semiconducting quantities, the contribution of the redistribution carriers to the electric field is analyzed from the Gauss’ s law. Numerical examples are carried out for an n-type Zn O nanowire in different locations induced by an applied concentrated end force. They include the electric potential, heavy hole(HH), light hole(LH), spin-orbit split-off(SO),and conduction band(CB) edges along the axial and thickness directions. Our results show that the applied force has a significant effect on the band energies. For instance, on the bottom surface along the axial direction, the bandgaps near the fixed end are greater than those near the loading end, and this trend is reversed on the top surface. Moreover,at a fixed axial location, the energy level of the lower side can be enhanced by applying a bending force at the end. The present results could be of significant guidance to the electronic devices and piezotronics.

关键词： piezoelectric semiconductor(PSC) mechanical bending energy band ZnO

Antifouling Technology Trends in Marine environmental Protection

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Journal of Bionic engineering 2021年第2期18卷 239-263页

作者： Limei Tian Yue Yin Wei Bing e Jin Key Laboratory of Bionic engineering Ministry of EducationJilin UniversityChangchun 130022China Weihai Institute for Bionics-Jilin University Weihai 264207China School of Chemistry and Life Science Changchun University of TechnologyChangchun 130012China

Marine fouling is a worldwide problem,which is harmful to the global marine ecological environment and economic *** traditional antifouling strategy usually uses toxic antifouling agents,which gradually exposes a serious environmental ***,green,long-term,broad-spectrum and eco-friendly antifouling technologies have been the main target of engineers and *** recent years,many eco-friendly antifouling technologies with broad application prospects have been developed based on the low toxicity and non-toxicity antifouling agents and *** this review,contemporary eco-friendly antifouling technologies and materials are summarized into bionic antifouling and non-bionic antifouling strategies(2000-2020).Non-bionic antifouling technologies mainly include protein resistant polymers,antifoulant releasing coatings,foul release coatings,conductive antifouling coatings and photodynamic antifouling *** antifouling technologies mainly include the simulated shark skin,whale skin,dolphin skin,coral tentacles,lotus leaves and other biology *** future research directions and challenges are also discussed in the end,and we expect that this review would boost the development of marine antifouling technologies.

关键词： biofouling antifouling technologies bionic non-bionic biofilm