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high-energy-density plasma in femtosecond-laser-irradiated nanowire-array targets for nuclear reactions

Matter and Radiation at Extremes 2022年第6期7卷 29-40页

作者： Defeng Kong Guoqiang Zhang Yinren Shou Shirui Xu Zhusong Mei Zhengxuan Cao Zhuo Pan Pengjie Wang Guijun Qi Yao Lou Zhiguo Ma Haoyang Lan Wenzhao Wang Yunhui Li Peter Rubovic Martin Veselsky Aldo Bonasera Jiarui Zhao Yixing Geng Yanying Zhao Changbo Fu Wen Luo Yugang Ma Xueqing Yan Wenjun Ma State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTSchool of PhysicsPeking UniversityBeijing 100871China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Key Laboratory of Nuclear Physics and Ion-Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Nuclear Science and Technology University of South ChinaHengyang 421001China INPAC and School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Institute of Experimental and Applied Physics Czech Technical University in PragueHusova 240/511000 Prague 1Czech Republic ELI Beamlines Center Institute of Physics of the Czech Academy of Sciences25241 DolníBrezanyCzechia Cyclotron Institute Texas A&M UniversityCollege StationTexas 77843USA Laboratori Nazionali del Sud INFNvia Santa Sofia62Catania 95123Italy Beijing Laser Acceleration Innovation Center HuairouBeijing 101400China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuanShanxi 030006China

In this work,the high-energy-density plasmas(HEDP)evolved from joule-class-femtosecond-laser-irradiated nanowire-array(NWA)targets were numerically and experimentally studied.The results of particle-in-cell simulations indicate that ions accelerated in the sheath field around the surfaces of the nanowires are eventually confined in a plasma,contributing most to the high energy densities.The protons emitted from the front surfaces of the NWA targets provide rich information about the interactions that occur.We give the electron and ion energy densities for broad target parameter ranges.The ion energy densities from NWA targets were found to be an order of magnitude higher than those from planar targets,and the volume of the HEDP was several-fold greater.At optimal target parameters,8%of the laser energy can be converted to confined protons,and this results in ion energy densities at the GJ/cm^(3) level.In the experiments,the measured energy of the emitted protons reached 4 MeV,and the changes in energy with the NWA’s parameters were found to fit the simulation results well.Experimental measurements of neutrons from 2H(d,n)3He fusion with a yield of(24±18)×10^(6)/J from deuterated polyethylene NWA targets also confirmed these results.

关键词： irradiated confined eventually

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Super-resolution fluorescence-assisted diffraction computational tomography reveals the threedimensional landscape of the cellular organelle interactome

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Light(Science & Applications) 2020年第1期9卷 1889-1903页

作者： Dashan Dong Xiaoshuai Huang Liuju Li Heng Mao Yanquan Mo Guangyi Zhang Zhe Zhang Jiayu Shen Wei Liu Zeming Wu Guanghui Liu Yanmei Liu Hong Yang Qihuang Gong Kebin Shi Liangyi Chen State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuanShanxi 030006China State Key Laboratory of Membrane Biology Beijing Key Laboratory of Cardiometabolic Molecular MedicineInstitute of Molecular MedicinePeking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China School of Software and Microelectronics Peking UniversityBeijing 100871China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China National Laboratory of Biomacromolecules Chinese Academy of Sciences Center for Excellence in BiomacromoleculesInstitute of BiophysicsBeijing 100101China Institute for Brain Research and Rehabilitation(IBRR) Guangdong Key Laboratory of Mental Health and Cognitive ScienceSouth China Normal UniversityGuangzhouChina Collaborative Innovation Center of Quantum Matter Peking UniversityBeijing 100871China PKU-IDG/McGovern Institute for Brain Research Beijing 100871China

The emergence of super-resolution(SR)fluorescence microscopy has rejuvenated the search for new cellular substructures.However,SR fluorescence microscopy achieves high contrast at the expense of a holistic view of the interacting partners and surrounding environment.Thus,we developed SR fluorescence-assisted diffraction computational tomography(SR-FACT),which combines label-free three-dimensional optical diffraction tomography(ODT)with two-dimensional fluorescence Hessian structured illumination microscopy.The ODT module is capable of resolving the mitochondria,lipid droplets,the nuclear membrane,chromosomes,the tubular endoplasmic reticulum,and lysosomes.Using dual-mode correlated live-cell imaging for a prolonged period of time,we observed novel subcellular structures named dark-vacuole bodies,the majority of which originate from densely populated perinuclear regions,and intensively interact with organelles such as the mitochondria and the nuclear membrane before ultimately collapsing into the plasma membrane.This work demonstrates the unique capabilities of SR-FACT,which suggests its wide applicability in cell biology in general.

关键词： landscape illumination partner

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Enhancing power factor of SnSe sheet with grain boundary by doping germanium or silicon

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npj Computational Materials 2020年第1期6卷 844-849页

作者： Jie Sun Jiabing Yu Yaguang Guo Qian Wang Center for Applied Physics and Technology Department of Materials Science and EngineeringHEDPSCollege of EngineeringPeking UniversityBeijing 100871China College of Optoelectronic Engineering Chongqing UniversityChongqing 400044China

Grain boundaries(GBs)widely exist in two-dimensional(2D)and three-dimensional(3D)materials in experiment,which significantly affect the thermoelectric performance because of the scattering effect on the transport of both electron and phonon.Motivated by the research progress in 3D SnSe,we have systematically studied the GBs in a SnSe monolayer including their stable geometric configurations,the effect of GBs on power factor and Seebeck coefficient,and the strategies to improve the performance by using first principles calculations combined with semiclassical Boltzmann theory.We find that the GBs increase the potential energy barrier of carriers and decrease the valley degeneracy of the conducting bands,leading to the reduction of Seebeck coefficient,as compared to that of the pristine SnSe sheet.We further demonstrate that the trapping gap states are effectively eliminated or reduced by doping germanium or silicon,leading to the enhanced electrical conductivity,power factor,and Seebeck coefficient.These findings shed lights on developing practical strategies for modulating the thermoelectric performance of 2D polycrystalline sheets.

关键词： doping power eliminated

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Size effect on transverse free vibrations of ultrafine nanothreads

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中国物理B:英文版 2023年第9期32卷 21-27页

作者：郑卓群李晗宿柱丁楠徐旭占海飞王立峰 State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Management Science and Information Engineering Jilin University of Finance and EconomicsChangchun 130117China College of Mathematics Jilin UniversityChangchun 130012China College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China School of Mechanical Medical and Process EngineeringQueensland University of TechnologyBrisbane 4001Australia

Due to their unique properties and appealing applications,low dimensional sp^(3)carbon nanostructures have attracted increasing attention recently.Based on the beam theory and atomistic studies,this work carries out a comprehensive investigation on the vibrational properties of the ultrathin carbon nanothreads(NTH).Size effect is observed in transverse free vibrations of NTHs.To quantify such effects,the modified couple stress theory(MCST)is utilized to modify the Timoshenko beam theory.According to the first four order frequencies of NTHs from atomistic simulations,the critical length scale parameter of MCST is calibrated as 0.1 nm.It is shown that MCST has minor effect on the first four order modal shapes,except for the clamped boundary.MCST makes the modal shapes at the clamped boundary closer to those observed in atomistic simulations.This study suggests that to some extent the MCST-based Timoshenko beam theory can well describe the transverse vibration characteristics of the ultrafine NTHs,which are helpful for designing and fabricating the NTH-based nanoscale mechanical resonators.

关键词： carbon nanothread size effect natural frequency modal shapes molecular dynamics simulation

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Four new corynanthe-type alkaloids from the roots of Alstonia scholaris

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Chinese Journal of Natural Medicines 2019年第12期17卷 918-923页

作者： ZHANG Jian LI Hua LI Yong LI Zi-Wei SANG Chen-Chen GAO Mei-Hua ZHANG Dong-Mei ZHANG Xiao-Qi YE Wen-Cai Institute of Traditional Chinese Medicine&Natural Products and Guangdong Provincial Engineering Research Center for Modernization of TCMCollege of PharmacyJinan UniversityGuangzhou 510632China Chinese Patent Medicine Department Guangdong Institute for Drug ControlGuangzhou 510663China

Four new corynanthe-type alkaloids,meloslines C–F(1–4),together with four known ones(5–8)were isolated from the roots of Alstonia scholaris.Their structures including absolute configurations were elucidated by extensive spectroscopic analysis and electronic circular dichroism(ECD)calculation.Compounds 1 and 2 exhibited potent vasorelaxant activity on endothelium-intact renal arteries precontracted with KCl.

关键词： Alstonia scholaris Apocynaceae Corynanthe-type alkaloids Vasorelaxant activity

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Insights into the adsorption of water and oxygen on the cubic CsPbBr_(3)surfaces:A first-principles study

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Chinese Physics B 2022年第4期31卷 545-551页

作者：张鑫屈和如歌雷鸣 State Key Laboratory of Information Photonics and Optical Communications and School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China College of Aeronautical Engineering Binzhou UniversityBinzhou 256603China

The degradation mechanism of the all-inorganic perovskite solar cells in the ambient environment remains unclear.In this paper,water and oxygen molecule adsorptions on the all-inorganic perovskite(CsPbBr_(3))surface are studied by density-functional theory calculations.In terms of the adsorption energy,the water molecules are more susceptible than the oxygen molecules to be adsorbed on the CsPbBr_(3)surface.The water molecules can be adsorbed on both the CsBr-and PbBr-terminated surfaces,but the oxygen molecules tend to be selectively adsorbed on the CsBr-terminated surface instead of the PbBr-terminated one due to the significant adsorption energy difference.While the adsorbed water molecules only contribute deep states,the oxygen molecules introduce interfacial states inside the bandgap of the perovskite,which would significantly impact the chemical and transport properties of the perovskite.Therefore,special attention should be paid to reduce the oxygen concentration in the environment during the device fabrication process so as to improve the stability and performance of the CsPbBr_(3)-based devices.

关键词： all-inorganic perovskite structural and electronic properties molecule adsorption density functional theory

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Synthesis of carbon nitride in moist environments:A defect engineering strategy toward superior photocatalytic hydrogen evolution reaction

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Journal of Energy Chemistry 2021年第3期30卷 403-413页

作者： Shuquan Huang Feiyue Ge Jia Yan Hongping Li Xingwang Zhu Yuanguo Xu Hui Xu Huaming Li School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu UniversityZhenjiang 212013JiangsuChina Department of Applied Biology and Chemical Technology and the State Key Laboratory of Chirosciences The Hong Kong Polytechnic UniversityHung HomHong KongChina

Intimate understanding of the synthesis-structure-activity relationships is an accessible pathway to overcome the intrinsic challenges of carbon nitride(g-C_(3)N_(4))photocatalysts.This work looks in the effects of humidity of the synthesis process to the morphology,chemical structure,band structure as well as the photocatalytic activity of g-C_(3)N_(4) materials.Four g-C_(3)N_(4) samples were prepared by heating melem in four gas environments:dry Ar,dry Air,moist Ar and moist Air.The photocatalytic activity measurements revealed that the samples synthesized in moist inert and oxidic gases environments displayed 20 and 10 times the photocata lytic H_(2) evolution activity of the samples synthesized in dry inert and oxidic gases environments,respectively.The reasons for this remarkable variety in photocata lytic activities had been through investigated.After all,the terminations of the carbon vacancies were identified as the dominant factor in enhancing H_(2) evolution performance.The work here thus demonstrating an example of defect engineering.

关键词： H_(2)evolution,g-C_(3)N_(4) Carbon vacancy Terminal functional groups

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Application of kernel ridge regression in predicting neutron-capture reaction cross-sections

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Communications in Theoretical Physics 2022年第9期74卷 98-104页

作者： T X Huang X H Wu P W Zhao State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

This article provides the first application of the machine-learning approach in the study of the cross-sections for neutron-capture reactions with the kernel ridge regression(KRR)approach.It is found that the KRR approach can reduce the root-mean-square(rms)deviation of the relative errors between the experimental data of the Maxwellian-averaged(n,γ)cross-sections and the corresponding theoretical predictions from 69.8%to 35.4%.By including the data with different temperatures in the training set,the rms deviation can be further significantly reduced to 2.0%.Moreover,the extrapolation performance of the KRR approach along different temperatures is found to be effective and reliable.

关键词： kernel ridge regression machine learning neutron-capture reaction

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Complete reduction of integrals in two-loop five-light-parton scattering amplitudes

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Chinese Physics C 2020年第9期44卷 62-68页

作者：关鑫刘霄马滟青 School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Center for high Energy Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

We reduce all the most complicated Feynman integrals in two-loop five-light-parton scattering amplitudes to basic master integrals,while other integrals can be reduced even easier.Our results are expressed as systems of linear relations in the block-triangular form,very efficient for numerical calculations.Our results are crucial for complete next-to-next-to-leading order quantum chromodynamics calculations for three-jet,photon,and/or hadron production at hadron colliders.To determine the block-triangular relations,we develop an efficient and general method,which may provide a practical solution to the bottleneck problem of reducing multiloop multiscale integrals.

关键词： Feynman integrals reduction five-light-parton scattering

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Theoretical Mechanistic Studies of Rh-Catalyzed c(sp^3)-H Amination:A Comparison with Co Analogue and Metal Effects

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Chinese Journal of Chemistry 2020年第12期38卷 1526-1532页

作者： Yang Yu Gen Luo Jimin Yang Yi Luo State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalianLiaoning 116024China Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601China

of main observation and conclusion The mechanism of Rh-catalyzed C(sp^3)—H amination has been computationally investigated.The reaction mechanism mainly involves sequential C(sp^3)—H activation,decarboxylation,nitrene migration insertion,and protonation steps.Competitive concerted metalation deprotonation(CMD)and external base assisted deprotonation(EBAD)pathways are found for the involved C(sp^3)—H activation in both Rh and Co analogous systems.This is different from the previously reported C(sp^2)—H activation,where the CMD is dominant.The key mechanistic difference between the two systems is found to be in the C(sp^3)—H activation step.In comparison with Rh species,the lower activity of Co complex toward the C(sp^3)—H activation could be ascribed to smaller atomic size of Co and thus larger steric repulsion between ancillary ligand and substrate along with the CMD pathway.In view of the EBAD pathway,however,the lower activity of Co species could be imputed to the triplet nature of Co center,which is against the electron transfer from the electron-rich carbon atom of the deprotonating C(sp^3)—H bond to the Co center.As to the subsequent decarboxylation and nitrene insertion steps,compared with the Co system,the relatively lower reactivity of Rh species is partially due to the stronger Rh—N bond,and the higher Ti(Rh—N)and n^*(Rh—N)orbital energies of the corresponding transition state structure.

关键词： structure. activation steps

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