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CONSTRUCTION OF GEOMETRIC PARTIAL DIFFERENTIAL EQUATIONS FOR LEVEL SETS

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Journal of Computational Mathematics 2010年第1期28卷 105-121页

作者： chong chen Guoliang Xu LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Beijing 100190 China LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

Geometric partial differential equations of level-set form are usually constructed by a variational method using either Dirac delta function or co-area formula in the energy functional to be minimized. However, the equations derived by these two approaches are not consistent. In this paper, we present a third approach for constructing the level-set form equations. By representing various differential geometry quantities and differential geometry operators in terms of the implicit surface, we are able to reformulate three classes of parametric geometric partial differential equations （second-order, fourth-order and sixth- order） into the level-set forms. The reformulation of the equations is generic and simple, and the resulting equations are consistent with their parametric form counterparts. We further prove that the equations derived using co-area formula are also consistent with the parametric forms. However, these equations are of much complicated forms than these given by the equations we derived.

关键词： Geometric partial differential equations Level set Differential geometry operators.

Quantum Curve and Bilinear Fermionic Form for the Orbifold Gromov–Witten Theory of P[r]

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Acta Mathematica Sinica,English Series 2024年第1期40卷 43-80页

作者： chong Yao chen Shuai GUO Mathematics Department Duke UniversityBox 90320DurhamNC 27708-0320USA School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

We construct the quantum curve for the Baker-Akhiezer function of the orbifold Gromov-Witten theory of the weighted projective line P[r].Furthermore,we deduce the explicit bilinear Fermionic formula for the(stationary... 详细信息

关键词： Quantum curve Free Fermions Gromov-Witten invariants Orbifold P^(1)

Particle simulation of grid system for krypton ion thrusters

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Chinese Journal of Aeronautics 2018年第4期31卷 719-726页

作者： Maolin chen Anbang SUN chong chen Guangqing XIA Science and Technology on Combustion Internal Flow and Thermo-Structure Laboratory Northwestern Polytechnical University State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong University State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology

The transport processes of plasmas in grid systems of krypton（Kr） ion thrusters at different acceleration voltages were simulated with a 3 D-PIC model, and the result was compared with xenon（Xe） ion thrusters. The variation of the screen grid transparency, the accelerator grid current ratio and the divergence loss were explored. It is found that the screen grid transparency increases with the acceleration voltage and decreases with the beam current, while the accelerator grid current ratio and divergence loss decrease first and then increase with the beam current. This result is the same with Xe ion thrusters. Simulation results also show that Kr ion thrusters have more advantages than Xe ion thrusters, such as higher screen grid transparency, smaller accelerator grid current ratio, larger cut-off current threshold, and better divergence loss characteristic. These advantages mean that Kr ion thrusters have the ability of operating in a wide range of current. Through comprehensive analyses, it can be concluded that using Kr as propellant is very suitable for a multimode ion thruster design.

关键词： Grid system Ion thrusters Krypton Particle in cell method Plasma

From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

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Progress in Natural Science:Materials International 2024年第1期34卷 66-73页

作者： Miao Chang Chiyao Tang chong-chen Wang chen Zhao Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment

Fundamental Understanding and Optimization Strategies for Dual‑Ion Batteries:A Review

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Nano-Micro Letters 2023年第8期15卷 205-224页

作者： chong chen Chun‑Sing Lee Yongbing Tang Advanced Energy Storage Technology Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Center of Super‑Diamond and Advanced Film(COSDAF) City University of Hong KongKowloon 999077Hong KongSARPeople’s Republic of China

There has been increasing demand for high-energy density and longcycle life rechargeable batteries to satisfy the ever-growing requirements for nextgeneration energy storage *** all available candidates,dual-ion batteries(DIBs)have drawn tremendous attention in the past few years from both academic and industrial battery communities because of their fascinating advantages of high working voltage,excellent safety,and environmental ***,the dynamic imbalance between the electrodes and the mismatch of traditional electrolyte systems remain *** fully employ the advantages of DIBs,the overall optimization of anode materials,cathode materials,and compatible electrolyte systems is urgently ***,we review the development history and the reaction mechanisms involved in ***,the optimization strategies toward DIB materials and electrolytes are *** addition,their energy-related applications are also ***,the research challenges and possible development directions of DIBs are outlined.

关键词： Dual-ion batteries Reaction mechanisms Optimization strategies Energy storage

Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

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Chinese Chemical Letters 2024年第5期35卷 77-84页

作者： Xiao-Hong Yi chong-chen Wang Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy EngineeringBeijing University of Civil Engineering and ArchitectureBeijing 100044China

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st *** to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy *** is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment *** this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were ***,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

关键词： Metal-organic frameworks Sponge foam Water decontamination Adsorption Catalysis

Quantum numbers of the pentaquark states Pc+ via symmetry analysis

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Communications in Theoretical Physics 2020年第12期72卷 145-151页

作者： chong-yao chen Muyang chen Yu-Xin Liu Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Department of Physics Hunan Normal UniversityChangsha 410081China

We investigate the quantum numbers of the pentaquark states Pc+,which are composed of 4(three flavors)quarks and an antiquark,by analyzing their inherent nodal structure in this *** that the four quarks form a tetrahedron or a square,and the antiquark is at the ground state,we determine the nodeless structure of the states with orbital angular moment L≤3,and in turn,the accessible low-lying *** the inherent nodal structure depends only on the inherent geometric symmetry,we propose the quantum numbers JPof the low-lying pentaquark states P_c^+may be■,■,■and■,independent of dynamical models.

关键词： pentaquark states exotic hadrons color confinement symmetry analysis

Characterization of an ionic liquid electrospray thruster with a porous ceramic emitter

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Plasma Science and Technology 2020年第9期22卷 66-74页

作者： chong chen Maolin chen Haohao ZHOU Combustion Internal Flow and Thennal-Structure LaboratoryNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China

An ionic liquid(IL)electrospray thruster was developed for application in micro-nano satellites or gravitational wave *** thruster employed a porous ceramic emitter with seven emitter strips located on its emission *** any liquid-supply device,IL was delivered through porous media to emitter strips via capillary *** emission sites then formed at the tip of each strip.A charged beam of up to 350μA(with a current density of 540μA cm^(-2))was stably produced in the negative ***,in the positive mode,a corona was observed which could prevent the thruster from emitting larger current.A time-of-flight mass spectrometer with significantly improved signal-to-noise ratio was built,which was used to obtain the mass distribution of the beam of the thruster.A retarding potential analysis was also *** test results showed that the thruster worked in the pure-ion regime,and delivered a maximum thrust of 67.1μN with specific impulses of 3952 s and 3117 s in the positive and negative modes,respectively.

关键词： electrospray thruster time-of-flight(TOF) retarding potential analysis(RPA)

pigenetic reprogramming in small cell lung cancer

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Cancer Biology & Medicine 2022年第8期19卷 1111-1116页

作者： Jingyao chen Xiangyu Pan Feifei Na Xuelan chen chong chen State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan UniversityChengdu 610044China Department of Thoracic Oncology West China HospitalSichuan UniversityChengdu 610044China

Small cell lung cancer(SCLC),a highly lethal lung cancer sub-type with distinct neuroendocrine-like features,accounts for 10%–15%of all lung *** overall 5-year survival rate remains less than 10%.SCLC is characterized by early metastasis,thus minimizing the potential patient benefits of *** recent decades,the first-line treatment for SCLC has remained chemotherapy combining etoposide and cisplatin(E/P).Despite high rates of response to E/P treatment,SCLC eventually relapses and is almost universally resistant to treatment at recurrence,thus making SCLC a recalcitrant ***,the limited knowledge regarding the molecular mechanisms underlying SCLC metastasis and resistance greatly hinders improvements in overall SCLC *** better understand the molecular mechanisms of SCLC and discover potential therapeutic targets,extensive efforts have continued for decades.

关键词： metastasis chemotherapy treatment