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Frontiers of physics 2018年第5期13卷 79-86页

作者： Xinzhou Deng Hualing Yang Shifei Qi Xiaohong Xu Zhenhua Qiao CQD Hefei National Laboratory for Physical Sciences at Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics and Department of Physics University of Science and Technology of China Hefei 230026 China School of Chemistry and Materials Science Shanxi Normal University Linfen 041004 China

Quantum anomalous Hall effect （QAHE） is a fundamental quantum transport phenomenon in con- densed matter physics. Until now, the QAHE has only been experimentally realized for Cr/V-doped （Bi, Sb）2We3 but at an extremely low observational temperature, thereby limiting its potential appli- cation in dissipationless quantum electronics. By employing first-principles calculations, we study the electronic structures of graphene co-doped with 5d transition metal and boron atoms based on a com- pensated n-p co-doping scheme. Our findings are as follows： i） The electrostatic attraction between the n- and p-type dopants effectively enhances the adsorption of metal adatoms and suppresses their undesirable clustering, ii） Hf-B and Os-B co-doped graphene systems can establish long-range ferro- magnetic order and open larger nontrivial band gaps because of the stronger spin-orbit coupling with the non-vanishing Berry curvatures to host the high-temperature QAHE. iii） The calculated Rashba splitting energies in Re-B and Pt-B co-doped graphene systems can reach up to 158 and 85 meV, re- spectively, which are several orders of magnitude higher than the reported intrinsic spin-orbit coupling strength.

关键词： graphene quantum anomalous Hall effect spin-orbit coupling

Real-world gaseous emission characteristics of natural gas heavy-duty sanitation trucks

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Journal of Environmental Sciences 2022年第5期34卷 319-329页

作者： Jiguang Wang Huaqiao Gui Zhiwen Yang Tongzhu Yu Xiaowen Zhang Jianguo Liu Key Laboratory of Environmental Optics and technology Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China university of Science and technology of China Hefei 230026China China Automotive technology and Research Center Co. LtdTianjin 300300China Innovation excellence center for urban atmospheric environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

As compared to conventional diesel heavy-duty vehicles,natural gas vehicles have been proved to be more eco-friendly due to their lower production of greenhouse gas and pollu-tant emissions,which are causing enormous adverse effects on global warming and air ***,natural gas vehicles were rarely studied before,especially through on-road *** this study,a portable emission measurement system(PEMS)was em-ployed to investigate the real-world emissions of nitrogen oxides(NO_(x))(nitrogen monoxide(NO),nitrogen dioxide(NO_(2))),total hydrocarbons(THC),carbon monoxide(CO),and carbon dioxide(CO_(2))from two liquified natural gas(LNG)China V heavy-duty cleaning sanitation trucks with different *** with the more aggressive driving behaviors,the ve-hicle with lower weight exhibited higher CO_(2)(3%)but lower NO_(x)(48.3%)(NO_(2)(78.2%)and NO(29.4%)),CO(44.8%),and THC(3.7%)emission *** driving behaviors were also favorable to the production of THC,especially those in the medium-speed range but sig-nificantly negative to the production of CO and NO_(2),especially those in the low-speed range with high engine *** particular,the emission rate ratio of NO_(2)/NO decreased with the increase of speed/scaled tractive power in different speed ranges.

关键词： Natural gas sanitation vehicle PEMS Gaseous pollutant emission

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Blood-testis barrier and spermatogenesis： lessons From genetically-modified mice

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Asian Journal of Andrology 2014年第4期16卷 572-580页

作者： Xiao-Hua Jiang Ihtisham Bukhari Wei Zheng Shi Yin Zheng Wang Howard J Cooke Qing-Hua Shi hefei National Laboratory for Physical Sciences at Microscale School of Life Sciences University of Science and Technology of China Hefei China Medical Research Council Human Genetics Unit and Institute of Genetics and Molecular Medicine University of Edinburgh Edinburgh United Kingdom Institute of Physics Chinese Academy of Sciences Hefei China.

The blood-testis barrier （BTB） is found between adjacent Sertoli cells in the testis where it creates a unique microenvironment for the development and maturation of meiotic and postmeiotic germ cells in seminiferous tubes. It is a compound proteinous structure, composed of several types of cell junctions including tight junctions （TJs）, adhesion junctions and gap junctions （GJs）. Some of the junctional proteins function as structural proteins of BTB and some have regulatory roles. The deletion or functional silencing of genes encoding these proteins may disrupt the BTB, which may cause immunological or other damages to meiotic and postmeiotic cells and ultimately lead to spermatogenic arrest and infertility. In this review, we will summarize the findings on the BTB structure and function from genetically-modified mouse models and discuss the future perspectives.

关键词： blood-testis barrier genetically-modified mouse seminiferous tubule sertoli cells spermatogenesis

Probabilistic Teleportation of the Three-Particle Entangled State via Entanglement Swapping

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Chinese Physics Letters 2001年第8期18卷 1004-1006页

作者： LU Hong Laboratory of Quantum Communication and Quantum Computation University of Science and Technology of ChinaHefei 230026 Department of Physics Foshan UniversityFoshan 528000

A scheme of teleportation of a three-particle entangled state via entanglement swapping is *** is shown that if a two-particle entangled state and a three-particle entangled state(both are not maximum entangled states... 详细信息

关键词： particle state probabilistic

Polyacrylic acid sodium salt film entrapped Ag-nanocubes as molecule traps for SERS detection

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Nano Research 2014年第8期7卷 1177-1187页

作者： Zhulin Huang Guowen Meng Qing Huang Bin Chen Fei Zhou Xiaoye Hu Yiwu Qian Haibin Tang Fangming Han Zhaoqin Chu Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanostructures Institute of Solid State Physics Chinese Academy of Sciences P. O. Box 1129 Hefei 230031 China university of Science and technology of China Hefei 230026 China Key Laboratory of Ion Beam Bioengineering Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 23003 I China

Surface-enhanced Raman spectroscopy （SERS） is a fast analytical technique for trace chemicals; however, it requires the active SERS-substrates to adsorb analytes, thus limiting target species to those with the desired affinity for substrates. Here we present networked polyacrylic acid sodium salt （PAAS） film entrapped Ag-nanocubes （denoted as Ag-nanocubes@PAAS） as an effective SERS-substrate for analytes with and without high affinity. Once the analyte aqueous solution is cast on the dry Ag-nanocubes@PAAS substrate, the bibulous PAAS becomes swollen forcing the Ag-nanocubes loose, while the analytes diffuse in the interstices among the Ag-nanocubes. When dried, the PAAS shrinks and pulls the Ag-nanocubes back to their previous aggregated state, while the PAAS network ＂detains＂ the analytes in the small gaps between the Ag-nanocubes for SERS detection. The strategy has been proven effective for not only single- analytes but also multi-analytes without strong affinity for Ag, showing its potential in SERS-based simultaneous multi-analyte detection of both adsorbable and non-adsorbable pollutants in the environment.

关键词： SERS Ag-nanocube polyacrylic acid sodium salt trace detection

Quantum nature of proton transferring across one-dimensional potential fields

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Chinese Physics B 2021年第4期30卷 417-424页

作者： Cheng Bi Quan Chen Wei Li Yong Yang Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

Proton transfer plays a key role in the applications of advanced energy materials as well as in the functionalities of biological *** this work,based on the transfer matrix method,we study the quantum effects of proton transfer in a series of one-dimensional(1 D) model potentials and numerically calculate the quantum probability of transferring across single and double barriers(wells).In the case of single barriers,when the incident energies of protons are above the barrier height,the quantum oscillations in the transmission coefficients depend on the geometric shape of the *** is found that atomic resonant tunneling(ART) not only presents in the rectangular single well and rectangular double barriers as expected,but also exists in the other types of potential wells and double *** hetero-structured double barriers,there is no resonant tunneling in the classical forbidden zone,i.e.,in the case when the incident energy(E_(i)) is lower than the barrier height(E_(b)).Furthermore,we have provided generalized analysis on the characteristics of transmission coefficients of hetero-structured rectangular double barriers.

关键词： proton transfer nuclear quantum effects atomic resonant tunneling double barriers

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Investigation of a Hot Filament Diamond Deposition by in situ Infrared Absorption

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High technology Letters 1996年第1期2卷 72-76页

作者：崔景彪 Department of Physics University of Science and Technology of ChinaHefei 230026P.R.China

In situ infrared absorption spectroscopy has been measured for a hot filament diamond growth process. Absorption of CH4 and C2H2 species at 3050 cm-1 and 730 cm-1 were detected respectively. The absorption intensity of CH4 decreases while that of C2H2 increases as filament temperature is raised. The correlation between infrared absorption intensity and diamond growth rate or diamond film quality was found. High C2H2 or low CH4 concentration in the reaction region leads to high quality diamond film growth and high growth rate.

关键词： Hot filament CVD In situ infrared absorption Diamond quality Growth rate

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Radiokrypton dating coming of age

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National Science Review 2016年第2期3卷 172-173页

作者： Zheng-Tian Lu hefei National Laboratory for Physical Sciences at the Microscale Synergetic Innovation Center of Quantum Information & Quantum PhysicsUniversity of Science and Technology of China

The dream of radiokrypton dating began in 1969 when Heinz Hugo Loosli and Hans Oeschger of the university of Bern first detected the decay of;Rr（half-life=230 000 yr）in krypton gas extracted from air[1].This isotope is produced in the upper atmosphere by cosmic-ray-induced spallation and neutron-activation of stable *** to its long residence time（;0;yr）in the atmosphere,;Rr is uniformly

关键词： Radiokrypton dating coming of age ATA

Successively Regioselective Electrosynthesis and Electron Transport Property of Stable Multiply Functionalized[60]Fullerene Derivatives

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Research 2020年第1期2020卷 283-291页

作者： Xing-Xing Yan Bairu Li Hao-Sheng Lin Fei Jin Chuang Niu Kai-Qing Liu Guan-Wu Wang Shangfeng Yang hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Soft Matter ChemistryCenter for Excellence in Molecular Synthesis of CASand Department of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026China hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Materials for Energy Conversionand Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China

With the recent advance in chemical modification of fullerenes,electrosynthesis has demonstrated increasing importance in regioselective synthesis of novel fullerene ***,we report successively regioselective synthesis of stable tetra-and hexafunctionalized[60]fullerene *** cycloaddition reaction of the electrochemically generated dianions from[60]fulleroindolines with phthaloyl chloride regioselectively affords 1,2,4,17-functionalized[60]fullerene derivatives with two attached ketone groups and a unique addition pattern,where the heterocycle is rearranged to a[5,6]-junction and the carbocycle is fused to an adjacent[6,6]-*** addition pattern is in sharp contrast with that of the previously reported biscycloadducts,where both cycles are appended to[6,6]-*** obtained tetrafunctionalized compounds can be successively manipulated to 1,2,3,4,9,10-functionalized[60]fullerene derivatives with an intriguing“S”-shaped configuration via a novel electrochemical ***,the stability of tetrafunctionalized[60]fullerene products allows them to be applied in planar perovskite solar cells as efficient electron transport layers.

关键词： synthesis successively addition

A mechanistic study on the regioselective Ni-catalyzed methylation–alkenylation of alkyne with AlMe3 and allylic alcohol

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Organic Chemistry Frontiers 2022年第1期9卷 163-172页

作者： Jiao Liu Deguang Liu Wan Nie Haizhu Yu Jing Shi hefei National Laboratory for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyDepartment of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026China Department of Chemistry Anhui UniversityHefeiAnhui 230026China

The recently reported Ni-catalyzed methylation–allylation of alkynes with allylic alcohols and AlMe3 reagents delivers valuable tetrasubstituted alkene units in a highly regioselective *** by the experimental significance and the mechanistic ambiguity(*** details of C–O bond activation,the function of the Lewis acid AlMe3,etc.),we conducted a detailed mechanistic study using density functional theory(DFT)*** reaction was found to occur via the C–O bond activation of allylic alcohol,allylation of alkyne,transmetalation,reductive elimination and catalyst regeneration ***3 could easily react with the allylic alcohol to form a cyclodialuminoxane species bearing two groups of Lewis acid–base *** this regard,the C(allyl)–O bond is remarkably activated,resulting in a relatively facile C–O activation(compared to the typical Lewis-acid mediated reactions).In addition,the Al–Me interaction is a double-edged sword to the methylation step:the cyclodialuminoxane group functions as the methyl resource,while the full dissociation of the Al–Me interaction(via a cis-to-trans isomerization)is a requisite to fully release the methyl *** this context,the“Me-relay”pathway involving the[Ni]–Me intermediate is found to be more plausible than all other mechanistic possibilities(such as the typical concerted Me-transfer mechanism in previous studies).

关键词： alcohol catalyzed allyl