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Temperature dependence of the plastic scintillator detector for DAMPE

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Chinese Physics C 2017年第1期41卷 139-144页

作者：王兆民余玉洪孙志宇岳珂闫铎张永杰周勇方芳黄文学陈俊岭 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China University of Science and Technology of China Hefei 230026 China

The Plastic Scintillator Detector（PSD） is one of the main sub-detectors in the DArk Matter Particle Explorer（DAMPE） project. It will be operated over a large temperature range from -10 to 30, so the temperature effect of the whole detection system should be studied in detail. The temperature dependence of the PSD system is mainly contributed by the three parts： the plastic scintillator bar, the photomultiplier tube（PMT）, and the Front End Electronics（FEE）. These three parts have been studied in detail and the contribution of each part has been obtained and discussed. The temperature coefficient of the PMT is -0.320（±0.033）%/℃, and the coefficient of the plastic scintillator bar is -0.036（±0.038）%/℃. This result means that after subtracting the FEE pedestal, the variation of the signal amplitude of the PMT-scintillator system due to temperature mainly comes from the PMT,and the plastic scintillator bar is not sensitive to temperature over the operating range. Since the temperature effect cannot be ignored, the temperature dependence of the whole PSD has been also studied and a correction has been made to minimize this effect. The correction result shows that the effect of temperature on the signal amplitude of the PSD system can be suppressed.

关键词： DAMPE PSD PMT temperature dependence correction

Effective interactions between two impurities in quasi-two-dimensional dipolar Bose–Einstein condensates

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Communications in Theoretical Physics 2020年第7期72卷 65-70页

作者： Fu-Lin Deng Tao Shi Su Yi cas Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China cas Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China

We investigate the effective interaction between two heavy impurities immersed in a quasi-twodimensional dipolar Bose-Einstein condensate via a variation *** show that the mediated interaction is highly tunable via the contact and the dipole-dipole interactions between the background gas ***,the mediated interaction potential may become an oscillating function of inter-impurity distance when roton excitation emerges under sufficiently strong dipolar *** system therefore provides an efficient way for tuning the mediated interaction between impurities.

关键词： dipolar gas impurity effective interaction roton excitation

Recent Advance in the Solar Wind Magnetosphere Ionosphere Link Explorer(SMILE)Mission

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空间科学学报 2022年第4期42卷 568-573页

作者： WANG Chi BRANDUARDI-RAYMONT G ESCOUBET C P State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 Mullard Space Science Laboratory University College LondonLondon RH56NT European Space Agency/European Space research and Technology Centre Noordwijk 2201 AZ

The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(cas),aiming to understand the interaction of the solar wind with the Earth’s magnetosphere in a global *** mission was adopted by cas in November 2016 and by ESA in March 2019 with a target launch date in the year *** report the recent progress of SMILE mission by May,2022.

关键词： SMILE Soft X-ray Imager(SXI) Ultra-Violet Imager(UVI) Light Ion Analyzer(LIA) MAGnetometer(MAG)

Extraction and separation of heavy rare earths from chloride medium byα-aminophosphonic acid HEHAPP

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Journal of Rare Earths 2018年第3期36卷 304-310页

作者： Shengting Kuang Zhifeng Zhang Yanling Li Haiqin Wei Wuping Liao State Key Laboratory of Rare Earth Resource Utilization ERCfor the Separation and Purification of REs and ThoriumChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

The extraction and separation of heavy rare earths（REs） using newly synthesized a-aminophosphonic acid extractant 2-ethylhexyl-3-（2-ethylhexylamino）pentan-3-yl phosphonic acid（HEHAPP, HA） in nheptane were investigated from chloride medium. The extraction stoichiometries of lanthanum, gadolinium, yttrium and lutetium are determined to be REA3 by the slope analysis method. The favorable separation factors of adjacent heavy REs（Ⅲ）,i.e. β（Y/Ho）, β（Er/Y）,β（Tm/Er）,β（Yb/Tm） and β（Lu/Yb）, are determined to be1.87,1.36, 3.21,3.22 and 1.93, respectively, when extracted from a binary system at proper condition. The loading capacities of HA for Ho, Er, Yb and Lu increase in the order Ho 〈 Er 〈 Yb 〈 Lu with the values being 0.201, 0.205, 0.216 and 0.229 mol/L, respectively. So HA would be a potential extractant for the separation of heavy REs（Ⅲ）. Among inorganic acids such as H2 SO4, HNO3 and HCl, HCl is tested to be the most effective stripping agent.

关键词： Heavy rare earths α-aminophosphonic acid Solvent extraction Separation

A multiple-target mRNA-LNP vaccine induces protective immunity against experimental multi-serotype DENV in mice

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Virologica Sinica 2022年第5期37卷 746-757页

作者： Lihong He Wenqiang Sun Limin Yang Wenjun Liu Jing Li cas Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing100101China Institute of Infectious Diseases Shenzhen Bay LaboratoryShenzhenGuangdong518000China University of Chinese Academy of Sciences Beijing100049China Institute of Microbiology Center for Biosafety Mega-ScienceChinese Academy of SciencesBeijing100101China

Dengue virus(DENV)is a mosquito-borne virus with a rapid spread to humans,causing mild to potentially fatal illness in hundreds of millions of people each *** to the large number of serotypes of the virus,there remains an unmet need to develop protective vaccines for a broad spectrum of the ***,we constructed a modified mRNA vaccine containing envelope domain III(E-DIII)and non-structural protein 1(NS1)coated with lipid *** multi-target vaccine induced a robust antiviral immune response and increased neutralizing antibody titers that blocked all four types of DENV infection in vitro without significant antibodydependent enhancement(ADE).In addition,there was more bias for Th1 than Th2 in the exact E-DIII and NS1-specific T cell responses after a single ***,intramuscular immunization limited DENV transmission in vivo and eliminated vascular *** findings highlight that chimeric allogeneic structural and non-structural proteins can be effective targets for DENV vaccine and that they can prevent the further development of congenital DENV syndrome.

关键词： Dengue virus(DENV) mRNA vaccine Envelope domain III(E-DIII) Non-structural protein 1(NS1) Multi-serotype Immune response

Astrophysical constraints on the proton-to-electron mass ratio with FAST

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research in Astronomy and Astrophysics 2019年第2期19卷 15-24页

作者： Xi Chen Simon P.Ellingsen Ying Mei Center for Astrophysics Guangzhou University Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physical Sciences University of Tasmania

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and distance scales. The possibility of variations in the dimensionless physical constant μ-the proton-to-electron mass ratio, can be tested by comparing astronomical measurements of the rest frequency of certain spectral lines at radio wavelengths with laboratory determinations. Different types of molecular transitions have different dependencies on μ and so observations of two or more spectral lines towards the same astronomical source can be used to test whether there is any evidence for either temporal or spatial changes in the physical fundamental constants. μ will change if the relative strength of the strong nuclear force compared to the electromagnetic force varies. Theoretical studies have shown that the rotational transitions of some molecules which have transitions in the frequency range that will be covered by FAST(e.g., CH_3 OH, OH and CH) are sensitive to changes in μ. A number of studies looking for possible variations in μ have been undertaken with existing telescopes, however, the greater sensitivity of FAST means it will open new opportunities to significantly improve upon measurements made to *** this paper, we discuss which molecular transitions and sources(both in the Galaxy and external galaxies)are likely targets for providing improved constraints on μ with FAST.

关键词： ISM:molecules radio lines:ISM techniques:radial velocities elementary particles

Bridging length and time scales in moving contact line problems

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Science China(Physics,Mechanics & Astronomy) 2016年第11期59卷 87-89页

作者： YaPu Zhao State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of Sciences Beijing 100049China

Physical,mechanical,chemical,and biological processes for various problems span length and time scales of many orders of magnitude[1-6].As a typical dynamic process,moving contact line（MCL）problem or droplet spreading consists of 7-8 length and time scales from the atomistic to the continuum[2],as shown in Figure 1.A grand challenge in MCL problems is to link these vastly different length and time *** these length and time scales origin from the competition among governing forces[7],

关键词：时间尺度移动接触线长度桥接生物过程 MCL 数量级连续性

Recent progress on multidimensional construction of helicenes

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Chinese Chemical Letters 2018年第1期29卷 40-46页

作者： Wei-Bin Lin Meng Li Lei Fang Chuan-Feng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Helicenes have attracted more and more attention in the field of photoelectric materials and asymmetric catalysis for their unique Tr-conjugated screw-shaped structures and excellent chiroptical properties. However, further study and application of helicenes are based on novel idea, delicate design, and efficient synthetic methods Recent development of helicenes has witness various smart designs and approaches. In order to obtain a systematical and vivid introduction of latest development of helicenes, the idea of multidimensional construction is proposed in this review, which concludes the construction of multi- dimensions from length, extent, and height. We hope that this idea could be helpful to forecast the trend of helicene chemistry and provide the design inspiration of novel helicenes.

关键词： HeliceneMultidimensional construction^r-Conjugated systemsChiralityCatalyst

Some new mesoscopic crossover length scales concerning the Hamaker constant

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Science China(Technological Sciences) 2019年第12期62卷 2310-2312页

作者： ZHAO YaPu State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

The last three decades have witnessed a global surge in nano-and micro-mechanics driven by the rapid development of nanotechnology,microelectromechanical systems(MEMS)and nanoelectromechanical systems(NEMS)[1].Although a generally accepted framework is still lacking for mesoscopic mechanics,four broad categories of viewpoints have been agreed upon[2]:(1)Continuum mechanics works quite well even for a few atoms in *** 1997,Richard ***(1943-2005),the late Nobel laureate,and Yakobson[3]once commented:“The behavior of the hollow tubules is complex,but still predictable with continuum-elastic *** its applications to nanotubes,the correspondence between the elastic model and molecular dynamics is *** laws of continuum mechanics are amazingly robust and al-low one to treat even intrinsically discrete objects only a few atoms in diameter.”

关键词： scales mechanics constant