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Measurement-device-independent quantum secure direct communication
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作者 ZengRong Zhou Yu Bo Sheng +3 位作者 PengHao Niu LiuGuo Yin GuiLu Long Lajos Hanzo 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第3期2-7,共6页
Quantum secure direct communication(QSDC)is a unique technique,which supports the secure transmission of confidential information directly through a quantum channel without the need for a secret key and for ciphertext... Quantum secure direct communication(QSDC)is a unique technique,which supports the secure transmission of confidential information directly through a quantum channel without the need for a secret key and for ciphertext.Hence this secure communication protocol fundamentally differs from its conventional counterparts.In this article,we report the first measurement-deviceindependent(MDI)QSDC protocol relying on sequences of entangled photon pairs and single photons.Explicitly,it eliminates the security loopholes associated with the measurement device.Additionally,this MDI technique is capable of doubling the communication distance of its conventional counterpart operating without using our MDI technique.We also conceive a protocol associated with linear optical Bell-basis measurements,where only two of the four Bell-basis states could be measured.When the number of qubits in a sequence reduces to 1,the MDI-QSDC protocol degenerates to a deterministic MDI quantum key distribution protocol. 展开更多
关键词 quantum information secure communication quantum communication
2018年中国基本城市土地利用类型制图(EULUC-China)
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作者 宫鹏 陈斌 +67 位作者 李雪草 刘涵 王杰 白玉琪 陈镜明 陈曦 房磊 冯帅龙 冯永玖 巩雅丽 顾浩 黄华兵 黄晓春 焦洪赞 康应东 雷光斌 李爱农 李晓婷 李郇 李月臣 李志林 李忠德 刘冲 刘春霞 刘卯丑 刘曙光 毛婉柳 苗长虹 倪好 潘起胜 齐述华 任浙豪 单卓然 沈少青 石敏俊 宋祎萌 苏墨 孙凯平 孙博 孙芳蒂 孙健 孙林 孙文尧 田甜 童小华 曾羲星 屠滢 王红 王兰 王犀 王宗明 武廷海 颉耀文 杨健 杨军 袁满 岳文泽 曾宏达 张阔 张能 张涛 张宇 赵峰 郑伊辰 周启鸣 Nicholas Clinton 朱智良 徐冰 《科学通报:英文版》 SCIE EI CSCD 2020年第3期182-187,共6页
土地利用是人类活动在土地空间的重要表现形式.由于数据和资金支持的限制,全国尺度城市土地利用的遥感制图研究仍相对缺乏.针对这一难题,本文提出了涵盖居住-休闲-交通-工业-办公五大类用地的"基本城市土地利用类型(EULUC)"... 土地利用是人类活动在土地空间的重要表现形式.由于数据和资金支持的限制,全国尺度城市土地利用的遥感制图研究仍相对缺乏.针对这一难题,本文提出了涵盖居住-休闲-交通-工业-办公五大类用地的"基本城市土地利用类型(EULUC)"的概念,并综合利用2018年的10米分辨率哨兵卫星数据,OpenStreetMap,珞珈一号夜间灯光数据,以及腾讯移动定位和高德兴趣点(POI)等社会大数据,实现了全国范围内城市土地利用制图.第一版中国基本城市土地利用制图结果共包括440798个地块(除道路用地),5大一级类和12个二级类总体分类精度分别为61.2%和57.5%.这是中国首套结合遥感和众源大数据,以地块尺度生产的面向对象的高分辨率城市土地利用图. 展开更多
关键词 EULUC-China 土地利用类型
离子液体插层导致的MoTe2,WTe2拓扑及超导性质的双重调控
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作者 张浩雄 阿瓦拜克力·肉苏里 +10 位作者 沈胜春 张柯楠 王冲 罗来鹏 王吉章 吴扬 徐勇 段文晖 姚宏 于浦 周树云 《科学通报:英文版》 SCIE EI CSCD 2020年第3期188-193,共6页
使拓扑材料具有超导电性是实现拓扑超导的一个重要途径.Td相的MoTe2和WTe2不仅具有新颖的拓扑性质,其物理特性紧密依赖于层间耦合作用的强弱.本工作通过一种新颖的实验方法,在MoTe2和WTe2单晶样品中插入离子液体的有机阳离子,制备出层... 使拓扑材料具有超导电性是实现拓扑超导的一个重要途径.Td相的MoTe2和WTe2不仅具有新颖的拓扑性质,其物理特性紧密依赖于层间耦合作用的强弱.本工作通过一种新颖的实验方法,在MoTe2和WTe2单晶样品中插入离子液体的有机阳离子,制备出层间距可调、性质稳定且超导增强的有机-无机复合样品.插层后的MoTe2样品属于三维弱拓扑绝缘体,超导转变温度从0.25 K大幅提高到了7 K;而插层后WTe2的超导转变温度提高到了具有量子自旋霍尔效应的单层WTe2的2.8倍(2.3 K).本工作通过插层离子液体的有机阳离子到MoTe2和WTe2样品中,实现对其拓扑及超导性质的双层调控,为后续研究拓扑超导、实现马约拉纳零模提供了新的机遇.另外,这一新方法具有普适性,可以广泛适用于各种层状材料,这将为在层状材料中探索和实现更多新颖物理性质提供便利. 展开更多
关键词 INTERCALATION of organic cation Topological MATERIALS WEYL SEMIMETALS MoTe2 and WTe2 Ionic liquids cations ORGANIC-INORGANIC hybrid MATERIALS Enhanced superconductivity
One-step method for preparing the experimental pure state in nuclear magnetic resonance
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作者 JingWei Wen XiaoCong Qiu +3 位作者 XiangYu Kong XinYu Chen Fan Yang GuiLu Long 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第3期112-115,共4页
Quantum computing is an emerging and promising research field in modern quantum physics and is committed to accelerating traditional calculation processes using the principle of quantum mechanics[1,2].Several computat... Quantum computing is an emerging and promising research field in modern quantum physics and is committed to accelerating traditional calculation processes using the principle of quantum mechanics[1,2].Several computation models have been proposed,including the circuit model[3],topologic quantum computation[4],adiabatic quantum computing[5],and duality quantum computing[6-8].Universal quantum computation generally includes a system initialization,evolutionary control,and a final-state readout[9],where the preparation of the initial state is a key step in the entire process. 展开更多
关键词 process. QUANTUM STATE
Observation of Coulomb Gap and Enhanced Superconducting Gap in Nano-Sized Pb Islands Grown on SrTiO3
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作者 袁永浩 王心童 +6 位作者 宋灿立 王立莉 何珂 马旭村 姚宏 李渭 薛其坤 《中国物理快报:英文版》 SCIE CAS CSCD 2020年第1期78-82,共5页
We report high-resolution scanning tunneling microscopy(STM)study of nano-sized Pb islands grown on SrTiO3,where three distinct types of gaps with different energy scales are revealed.At low temperature,we find that t... We report high-resolution scanning tunneling microscopy(STM)study of nano-sized Pb islands grown on SrTiO3,where three distinct types of gaps with different energy scales are revealed.At low temperature,we find that the superconducting gap(△s)in nano-sized Pb islands is significantly enhanced from the one in bulk Pb,while there is no essential change in superconducting transition temperature Tc,giving rise to a larger BCS ratio 2△s/kBTc~8.31 and implying stronger electron-phonon coupling.The stronger coupling can originate from the interface electron-phonon interactions between Pb islands and SrTiO3.As the superconducting gap is totally suppressed under applied magnetic field,the Coulomb gap with apparent V-shape emerges.Moreover,the size of Coulomb gap(Ac)depends on the lateral size of Pb islands(R)with △c-1/R^035,indicating that quantum size effect can significantly influence electronic correlations.Our experimental results shall shed important light on the interplay among superconductivity,quantum size effect and correlations in nano-sized strong-coupling superconductors. 展开更多
关键词 sized stronger PHONON
Entanglement purification for memory nodes in a quantum network
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作者 GuanYu Wang GuiLu Long 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第2期47-54,共8页
The entanglement between quantum memory nodes is a prerequisite in a quantum network, and the diamond nitrogen-vacancy(NV) center is a promising candidate serving as a quantum memory node. Here, we investigate the pos... The entanglement between quantum memory nodes is a prerequisite in a quantum network, and the diamond nitrogen-vacancy(NV) center is a promising candidate serving as a quantum memory node. Here, we investigate the possibility of achieving an entanglement purification protocol(EPP) for entangled NV centers in distant diamonds. To construct the EPP, we design a nondestructive parity-check detector(PCD) utilizing an auxiliary polarization-entangled photon pair, which makes our EPP less time consuming and insensitive to the phase fluctuation of the optical path length. The satisfied fidelity of an NV center pair after purification and efficiency of obtaining a purified NV center pair with our EPP can be obtained with current experimental techniques in the realistic condition. This EPP is useful for a quantum network in which NV centers are used as quantum memory nodes. 展开更多
关键词 entanglement purification memory nodes quantum network nitrogen-vacancy center system parity-check detectors
Overview to the Hard X-ray Modulation Telescope (Insight-HXMT) Satellite
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作者 Shuang-Nan Zhang TiPei Li +115 位作者 FangJun Lu LiMing Song YuPeng X u CongZhan Liu Yong Chen XueLei Cao QingCui Bu Zhi Chang Gang Chen Li Chen TianXiang Chen YiBao Chen YuPeng Chen Wei Cui WeiWei Cui JingKang Deng YongWei Dong Yuan Yuan Du MinXue Fu GuanHua Gao He Gao Min Gao MingYu Ge YuDong G u Ju Guan Can Gungor ChengCheng Guo DaWei Han Wei Hu Yue Huang Jia Huo ShuMei Jia LuHua Jiang WeiChun Jiang Jing Jin YongJie Jin Bing Li ChengKui Li Gang Li MaoShun Li Wei Li Xian Li XiaoBo Li XuFang Li YanGuo Li ZiJian Li ZhengWei Li XiaoHua Liang JinYuan Liao GuoQing Liu HongWei Liu ShaoZhen Liu' XiaoJing Liu Yuan Liu YiNong Liu Bo Lu XueFeng Lu Tao Luo Xiang M a Bin Meng Yi Nang JianYin N ie Ge Ou JinLu Q u Na Sai RenCheng Shang GuoHong Shen Liang Sun Ying Tan Lian Tao YouLi Tuo Chen Wang ChunQin Wang GuoFeng Wang HuanYu Wang Juan Wang WenShuai Wang YuSa Wang XiangYang Wen BaiYang Wu BoBing Wu Mei Wu GuangCheng Xiao ShaoLin Xiong LinLi Yan JiaWei Yang Sheng Yang YanJi Yang QiBin Yi Bin Yuan AiMei Zhang ChunLei Zhang、ChengMo Zhang Fan Zhang HongMei Zhang Juan Zhang Qiang Zhang ShenYi Zhangs Shu Zhang Tong Zhang WanChang Zhang Wei Zhang WenZhao Zhang Yi Zhang YiFei Zhang YongJie Zhang Yue Zhang Zhao Zhang Zhi Zhang ZiLiang Zhang HaiSheng Zhao XiaoFan Zhao ShiJie Zheng JianFeng Zhou YuXuan Zhu Yue Zhu RenLin Zhuang 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第4期2-19,共18页
As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray as... As China’s first X-ray astronomical satellite, the Hard X-ray Modulation Telescope (HXMT), which was dubbed as Insight-HXMT after the launch on June 15, 2017, is a wide-band(1-250 ke V) slat-collimator-based X-ray astronomy satellite with the capability of all-sky monitoring in 0.2-3 Me V. It was designed to perform pointing, scanning and gamma-ray burst(GRB)observations and, based on the Direct Demodulation Method (DDM), the image of the scanned sky region can be reconstructed.Here we give an overview of the mission and its progresses, including payload, core sciences, ground calibration/facility, ground segment, data archive, software, in-orbit performance, calibration, background model, observations and some preliminary results. 展开更多
关键词 X-and y-ray telescopes and instrumentation neutron stars black holes X-ray binaries y-ray bursts
可对抗联合攻击的设备无关量子安全直接通信
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作者 周澜 盛宇波 龙桂鲁 《科学通报:英文版》 SCIE EI CSCD 2020年第1期12-20,M0003共10页
本文提出了第一个设备无关量子安全直接通信(DI-QSDC)方案,并分析其在联合攻击模式下的安全性和通信效率.DI-QSDC不仅能免除对实验设备的高要求,还能增强通信的安全性.然而,在实际噪声量子信道条件下,信道噪声引起的光子传输丢失和退相... 本文提出了第一个设备无关量子安全直接通信(DI-QSDC)方案,并分析其在联合攻击模式下的安全性和通信效率.DI-QSDC不仅能免除对实验设备的高要求,还能增强通信的安全性.然而,在实际噪声量子信道条件下,信道噪声引起的光子传输丢失和退相干效应导致DI-QSDC的通信效率较低、通信距离短,且可能出现信息丢失及信息错误.同时,光子传输丢失和退相干效应还可能导致部分信息泄露,威胁DI-QSDC的绝对安全性.为克服光子传输丢失和退相干效应,本文在DI-QSDC方案中引入量子态指示放大及纠缠纯化方案.改良后的DI-QSDC方案能完全消除信息丢失,有效延长通信距离,提高信息正确度,并完全消除信息泄露,保证通信的绝对安全.因此,改良的DI-QSDC方案在未来量子通信领域具有较大的应用潜力. 展开更多
关键词 QUANTUM CRYPTOGRAPHY Device-independent QUANTUM secure direct COMMUNICATION Information security COMMUNICATION efficiency
Modeling and Simulation of Packet Delivery Rate in LTE-V Network Based on Markov Chain
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作者 Mengkai Shi Yaohan Tang +2 位作者 Xiangyun Zhang Yi Zhang Jun Xu 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第3期357-367,共11页
As one of the most promising communication technologies for vehicular networks, LTE-V has the advantages of wide coverage and a high transmission rate. 3 GPP released the technical specification of LTE-V in March 2017... As one of the most promising communication technologies for vehicular networks, LTE-V has the advantages of wide coverage and a high transmission rate. 3 GPP released the technical specification of LTE-V in March 2017, launching a spate of related research and industrialization. In this paper, we propose a communication model based on Markov process to evaluate the reliability of LTE-V. We derived the Packet Delivery Rate(PDR) of LTE-V based on the model. Moreover, we use Poisson process to model the distribution of vehicles on a highway,then combine the communication model with the vehicles’ distribution to derive the PDR under this scenario. To verify the correctness of the proposed model, we established a simulation program on the MATLAB platform. By comparing the simulation results and the mathematical results, we found that simulation results are a very good fit for the model. 展开更多
关键词 Vehicle-to-everything(V2X) LTE-V VEHICLE INFRASTRUCTURE cooperation system PACKET delivery rate
Microstructural evolution and mechanical properties of laser-welded joints of medium manganese steel
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作者 Yang Cao Chong Luo +6 位作者 Lin Zhao Yun Peng Liang Song Cheng-yong Ma Zhi-ling Tian Min-lin Zhong Yan-jie Wang 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2020年第1期75-87,共13页
The cold-rolled 5% medium Mn steel was butt-welded using a fiber laser.The microstructure,distribution of microhardness,and tensile properties of the base metal(BM)and welded joint were investigated.The results showed... The cold-rolled 5% medium Mn steel was butt-welded using a fiber laser.The microstructure,distribution of microhardness,and tensile properties of the base metal(BM)and welded joint were investigated.The results showed that the fusion zone of the welded joint had the highest microhardness due to the formatio n of 100%marten site.A finely mixed microstructure of martensite,ferrite,and austenite was formed in the heat-affected zone,and there was no softened zone in this area.The tensile test results indicated that the ultimate tensile sirength and yield strength were higher for the joint than for BM.The joint efficiency was approximately 100%.All samples of the welded joirn failed at the location of BM during tensile deformation.The fracture surfaces of the BM and welded joint were mainly ductile fractures.The BM and welded joint exhibited strain rate independence of the tensile strength and yield strength at strain rates of 0.01-1 s_1,while the yield strength of the BM and welded joint increased rapidly when the strain rate reached 5 s_1 due to changes in the dislocation moveme nt mechanisms.The uniform elongation of the BM and welded joint decreased with in creasing strain rate. 展开更多
关键词 Medium Mn steel-Microstructure MICROHARDNESS Tensile property Laser welding
台市场的公共监管、私人监管与协同监管:一个对比研究
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作者 王勇 刘航 冯骅 《经济研究》 CSSCI 北大核心 2020年第3期148-162,共15页
本文通过构建动态博弈模型,从监管机制的视角对比分析了平台市场中政府和平台企业不同的监管方式对卖家质量选择与监管激励的影响。本文区分了三种不同的监管模式:(1)政府直接对卖家进行单一的公共监管;(2)平台企业对卖家进行单一的私... 本文通过构建动态博弈模型,从监管机制的视角对比分析了平台市场中政府和平台企业不同的监管方式对卖家质量选择与监管激励的影响。本文区分了三种不同的监管模式:(1)政府直接对卖家进行单一的公共监管;(2)平台企业对卖家进行单一的私人监管;(3)政府和平台企业对卖家进行协同监管。通过对比三种监管模式下的均衡结果以及比较静态分析结果发现:对于单一监管模式,如果平台市场规模较大,平台企业私人监管下的商品质量将高于政府公共监管的质量水平;对于协同监管模式,如果平台企业承担的连带责任较大,政府与平台协同监管下的商品质量将高于任何一种单一监管模式。另外,政府与平台的监管力度并非简单的互补或替代,两者间的关系取决于处罚强度、平台规模、连带责任等参数。最后,从监管激励角度上看,对卖家处罚强度并非越高越好,存在一个适中的强度能够最大化并且最优地协调政府和平台的监管力度。 展开更多
关键词 平台市场 监管机制 平台治理 动态博弈
Hunting potassium geoneutrinos with liquid scintillator Cherenkov neutrino detectors
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作者 王喆 陈少敏 《中国物理C:英文版》 SCIE CAS CSCD 2020年第3期18-27,共10页
The research on geoneutrinos is a new interdisciplinary subject involving particle experiments and geo-science.Potassium-40(40K)decays contribute roughly to 1/3 of the radiogenic heat of the Earth,which is not yet acc... The research on geoneutrinos is a new interdisciplinary subject involving particle experiments and geo-science.Potassium-40(40K)decays contribute roughly to 1/3 of the radiogenic heat of the Earth,which is not yet accounted for by experimental observation.Solar neutrino experiments with liquid scintillators have observed uranium and thorium geoneutrinos and are the most promising experiments with regard to low-background neutrino detection.In this study,we present the new concept of using liquid-scintillator Cherenkov detectors to detect the neutrino-electron elastic scattering process of 40K geoneutrinos.Liquid-scintillator Cherenkov detectors using a slow liquid scintillator achieve this goal with both energy and direction measurements for charged particles.Given the directionality,we can significantly suppress the dominant intrinsic background originating from solar neutrinos in conventional liquid-scintillator detectors.We simulated the solar-and geo-neutrino scatterings in the slow liquid scintillator detector,and implemented energy and directional reconstructions for the recoiling electrons.We found that 40K geoneutrinos can be detected with three-standard-deviation accuracy in a kiloton-scale detector. 展开更多
关键词 liquid-scintillator Cherenkov detector slow liquid scintillator geoneutrino 40K neutrino
Collision Avoidance Strategy Supported by LTE-V-Based Vehicle Automation and Communication Systems for Car Following
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作者 Jiayang Li Yi Zhang +2 位作者 Mengkai Shi Qi Liu Yi Chen 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第1期127-139,共13页
We analyzed and improved a collision avoidance strategy, which was supported by Long Term EvolutionVehicle(LTE-V)-based Vehicle-to-Vehicle(V2 V) communication, for automated vehicles. This work was completed in two st... We analyzed and improved a collision avoidance strategy, which was supported by Long Term EvolutionVehicle(LTE-V)-based Vehicle-to-Vehicle(V2 V) communication, for automated vehicles. This work was completed in two steps. In the first step, we analyzed the probability distribution of message transmission time, which was conditional on transmission distance and vehicle density. Our analysis revealed that transmission time exhibited a near-linear increase with distance and density. We also quantified the trade-off between high/low resource reselection probabilities to improve the setting of media access parameters. In the second step, we studied the required safety distance in accordance with the response time, i.e., the transmission time, derived on the basis of a novel concept of Responsibility-Sensitive Safety(RSS). We improved the strategy by considering the uncertainty of response time and its dependence on vehicle distance and density. We performed theoretical analysis and numerical testing to illustrate the effectiveness of the improved robust RSS strategy. Our results enhance the practicability of building driverless highways with special lanes reserved for the exclusive use of LTE-V vehicles. 展开更多
关键词 VEHICLE AUTOMATION and communication COLLISION AVOIDANCE Long Term Evolution-Vehicle(LTE-V) Responsibility-Sensitive Safety(RSS)
Synthesis and biological evaluation of piperidyl benzimidazole carboxamide derivatives as potent PARP-1 inhibitors and antitumor agents
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作者 Xinwei Zhang Cunlong Zhang +4 位作者 Lin Tang Kuan Lu Huan Zhao Weibin Wu Yuyang Jiang 《中国化学快报:英文版》 SCIE CAS CSCD 2020年第1期136-140,共5页
We have synthesized a series of compounds based on a piperidyl benzimidazole carboxamide structure,and tested their PARP-1 inhibitory activity,as well as cellular inhibitory activity.Some of them show great potency as... We have synthesized a series of compounds based on a piperidyl benzimidazole carboxamide structure,and tested their PARP-1 inhibitory activity,as well as cellular inhibitory activity.Some of them show great potency as PARP-1 inhibitors and antitumor activity,which are valuable for further research.In addition,the predicted ADME properties and proposed binding mode with PARP-1 of the compounds were obtained via computational simulation. 展开更多
关键词 PARP-1 inhibitor Piperidyl benzimidazole carboxamide A-620223 Structure-activity relationship Antitumor activity
Dual-ion hybrid supercapacitor:Integration of Li-ion hybrid supercapacitor and dual-ion battery realized by porous graphitic carbon 预览
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作者 Changzhen Zhan Xiaojie Zeng +4 位作者 Xiaolong Ren Yang Shen Ruitao Lv Feiyu Kang Zheng-Hong Huang 《能源化学:英文版》 SCIE EI CAS CSCD 2020年第3期180-184,共5页
Lithium-ion hybrid supercapacitors(Li-HSCs) and dual-ion batteries(DIBs) are two types of energy storage devices that have attracted extensive research interest in recent years. Li-HSCs and DIBs have similarities in d... Lithium-ion hybrid supercapacitors(Li-HSCs) and dual-ion batteries(DIBs) are two types of energy storage devices that have attracted extensive research interest in recent years. Li-HSCs and DIBs have similarities in device structure, tendency for ion migration, and energy storage mechanisms at the negative electrode. However, these devices have differences in energy storage mechanisms and working potentials at the positive electrode. Here, we first realize the integration of a Li-HSC and a DIB to form a dual-ion hybrid supercapacitor(DIHSC), by employing mesocarbon microbead(MCMB)-based porous graphitic carbon(PGC) with a partially graphitized structure and porous structure as a positive electrode material. The MCMB-PGC-based DIHSC exhibits a novel dual-ion battery-capacitor hybrid mechanism: it exhibits excellent electronic double-layer capacitor(EDLC) behavior like a Li-HSC in the low-middle wide potential range and anion intercalation/de-intercalation behavior like a DIB in the high-potential range. Two types of mechanisms are observed in the electrochemical characterization process, and the energy density of the new DIHSC is significantly increased. 展开更多
关键词 Dual-ion HYBRID SUPERCAPACITOR HYBRID SUPERCAPACITOR Lithium-ion BATTERY Dual-ion BATTERY Porous graphitic carbon HYBRID mechanism
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Characteristics and Comparison of Different Downscaling Methods in Global Climate Model 预览
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作者 Feng KONG 《气象与环境研究:英文版》 CAS 2020年第1期40-44,47共6页
Global climate change greatly impedes the sustainable development of human society.And severe consequences could arise unless effective measures are taken to prevent them under the condition that we have a clear under... Global climate change greatly impedes the sustainable development of human society.And severe consequences could arise unless effective measures are taken to prevent them under the condition that we have a clear understanding of the trend of climate change.Currently,the most practical way to predict trend of climate change is GCM.However,GCM is unavailable in predicting detailed regional climate due to the lack of regional information and a relatively low spatial resolution of GCM.Such shortcoming is supplemented by the methods of downscaling which fall into three types:dynamical downscaling,statistical downscaling and the combination of statistical and dynamic downscaling.This paper aims at explaining in detail the methods of downscaling mentioned above and comparing their advantages and disadvantages in the hope of offering a reference for global climate prediction. 展开更多
关键词 CLIMATE PREDICTION DYNAMICAL DOWNSCALING STATISTICAL DOWNSCALING COMBINATION of STATISTICAL and dynamic DOWNSCALING
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Electronic structure of correlated topological insulator candidate YbB6 studied by photoemission and quantum oscillation
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作者 张腾 李岗 +9 位作者 孙淑翠 秦娜 康璐 姚淑华 翁红明 S K Mo 李璐 柳仲楷 杨乐仙 陈宇林 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第1期70-75,共6页
Angle-resolved photoemission spectroscopy(ARPES)and torque magnetometry(TM)measurements have been carried out to study the electronic structures of a correlated topological insulator(TI)candidate Yb B6.We observed cle... Angle-resolved photoemission spectroscopy(ARPES)and torque magnetometry(TM)measurements have been carried out to study the electronic structures of a correlated topological insulator(TI)candidate Yb B6.We observed clear surface states on the[001]surface centered at theГ^- and М^- points of the surface Brillouin zone.Interestingly,the fermiology revealed by the quantum oscillation of TM measurements agrees excellently with ARPES measurements.Moreover,the band structures we observed suggest that the band inversion in Yb B6 happens between the Yb5 dand B2bands,instead of the Yb5dand Yb4fbands as suggested by previous theoretical investigation,which will help settle the heavy debate regarding the topological nature of samarium/ytterbium hexaborides. 展开更多
关键词 topological insulator electronic structure surface states
A novel aptasensor strategy for protein detection based on G-quadruplex and exonuclease Ⅲ-aided recycling amplification
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作者 Huan Shi Tian Jin +4 位作者 Jiewen Zhang Xiaoting Huang Chunyan Tan Yuyang Jiang Ying Tan 《中国化学快报:英文版》 SCIE CAS CSCD 2020年第1期155-158,共4页
The detection of biomarkers is of great significance in the diagnosis of numerous diseases,especially cancer.Herein,we developed a sensitive and universal fluorescent aptasensor strategy based on magnetic beads,DNA G-... The detection of biomarkers is of great significance in the diagnosis of numerous diseases,especially cancer.Herein,we developed a sensitive and universal fluorescent aptasensor strategy based on magnetic beads,DNA G-quadruplex,and exonuclease Ⅲ(Exo Ⅲ).In the presence of a target protein,a label-free single strand DNA(ssDNA)hybridized with the aptamer was released as a trigger DNA due to specific recognition between the aptamer and target.Subsequently,ssDNA initiates the ExoⅢ-aided recycling to amplify the fluorescence signal,which was caused by N-methylmesoporphyrin IX(NMM)insertion into the G-quadruplex structure.This proposed strategy combines the excellent specificity between the aptamer and target,high sensitivity of the fluorescence signal by G-quadruplex and ExoⅢ-aided recycling amplification.We selected(50-1200 nmol/L)MUC1,a common tumor biomarker,as the proof-of-concept target to test the specificity of our aptasenso r.Results reveal that the sensor sensitively and selectively detected the target protein with limits of detection(LODs)of 3.68 and 12.83 nmol/L in buffer solution and 10%serum system,respectively.The strategy can be easily applied to other targets by simply substituting corresponding aptamers and has great potential in the diagnosis and monitoring of several diseases. 展开更多
关键词 APTASENSOR ExonucleaseⅢ-aided recycling AMPLIFICATION G-QUADRUPLEX Magnetic beads MUC1
2019年中国经济运行情况分析与2020年展望
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作者 许宪春 刘瑾钰 《经济学动态》 CSSCI 北大核心 2020年第2期3-13,共11页
本文以国民经济生产、使用和收入分配为基本框架,运用相应统计指标和统计数据对2019年中国经济运行情况进行分析,对2020年情况予以展望。2019年,中国GDP增速呈回落走势,但始终处于预期目标范围内,第三产业和消费需求分别从生产和需求角... 本文以国民经济生产、使用和收入分配为基本框架,运用相应统计指标和统计数据对2019年中国经济运行情况进行分析,对2020年情况予以展望。2019年,中国GDP增速呈回落走势,但始终处于预期目标范围内,第三产业和消费需求分别从生产和需求角度对经济增长起主要拉动作用;全国居民人均可支配收入保持平稳增长,规模以上工业企业利润总额由2018年较快增长转为下降;居民消费价格涨幅比2018年有所扩大;产业结构、需求结构和收入分配结构继续改善;新经济新动能保持较快增长。初步判断,2020年中国GDP增速可能会比2019年有所回落;创新驱动政策将会推动新经济新动能继续保持较快增长,减缓传统经济下行压力;投资需求增速与2019年大体持平,消费需求和净出口需求增速比2019年有所回落;全国居民人均可支配收入和规模以上工业企业利润总额增速比2019年有所回落。 展开更多
关键词 统计数据 经济运行 分析 展望
Material Compatibility of Hexamethyldisiloxane as Organic Rankine Cycle Working Fluids at High Temperatures
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作者 DAI Xiaoye SHI Lin QIAN Weizhong 《热科学学报:英文版》 SCIE EI CAS CSCD 2020年第1期25-31,共7页
The organic Rankine cycle(ORC)is a promising technology for industrial waste heat recovery and renewable energy utilization.High temperature ORCs have attracted particular interest because of their high thermal effici... The organic Rankine cycle(ORC)is a promising technology for industrial waste heat recovery and renewable energy utilization.High temperature ORCs have attracted particular interest because of their high thermal efficiencies and outputs.The material compatibility of working fluid is a significant limitation for the working fluid selection and system design for high temperature ORCs.This work presents a method for studying the material compatibility of ORC working fluids based on the calculated conditions of the ORCs and matching of components,temperatures,and materials.Hexamethyldisiloxane(MM)was chosen as the test fluid.The experimental results show that 304 stainless steel has better compatibility with MM than copper as the material of evaporators.Fluoric rubber is not a suitable sealing material for high temperature ORCs with MM as the working fluids because of the bad compatibility.Mineral oil has better compatibility with MM than polyol ester(POE)lubricant as the lubricant for the fluid pump. 展开更多
关键词 organic Rankine cycle(ORC) material compatibility high temperatures hexamethyldisiloxane(MM)
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