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Quantum confinement of carriers in the type-I quantum wells structure

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chinese physics B 2024年第9期33卷 553-558页

作者： Xinxin Li Zhen Deng Yang jiang Chunhua Du haiqiang jia Wenxin wang hong chen Key laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials andDevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChineseAcademy of SciencesBeijing 100190China Center of Materials and Optoelectronics Engineering University of Chinese Academy ofSciencesBeijing 100049China The Yangtze River Delta physics Research Center Liyang 213000China Songshan Lake Materials laboratory Dongguan 523808China

Quantum confinement is recognized to be an inherent property in low-dimensional ***,it is believed that the carriers trapped within the well cannot escape due to the discrete energy ***,our previous research has revealed efficient carrier escape in low-dimensional structures,contradicting this conventional *** this study,we review the energy band structure of quantum wells along the growth direction considering it as a superposition of the bulk material dispersion and quantization energy dispersion resulting from the quantum confinement across the whole Brillouin *** accounting for all wave vectors,we obtain a certain distribution of carrier energy at each quantized energy level,giving rise to the energy *** results enable carriers to escape from the well under the influence of an electric ***,we have compiled a comprehensive summary of various energy band scenarios in quantum well structures relevant to carrier *** a new interpretation holds significant value in deepening our comprehension of low-dimensional energy bands,discovering new physical phenomena,and designing novel devices with superior performance.

关键词： energy band quantum confinement type-I quantum wells low-dimensional structures

Characterization of different-Al-content AlGaN/GaN heterostructures on sapphire

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Science china(physics,Mechanics & Astronomy) 2010年第1期53卷 49-53页

作者： DING Guojian , GUO LiWei, xing zhigang, chen Yao, XU PeiQiang, jia haiqiang, ZHOU JunMing & chen hong beijing national laboratory of condensed matter physics, institute of physics, chinese academy of sciences, beijing 100190, china chinese academy of sciences Beijing National Laboratory of Condensed Matter Physics Institute of Physics Beijing China (GRID:grid.9227.e) (ISNI:***)

Al x Ga 1-x N/GaN high-electron-mobility transistor (HEMT) structures with Al composition ranging from x = 0.13 to 0.36 are grown on sapphire substrates by low-pressure metalorganic chemical vapor deposition (LP-MOCVD). The effects of Al content on crystal quality, surface morphology, optical and electrical characteristics of the AlGaN/GaN heterostructures have been analyzed. Although high Al-content (36%) heterostructure exhibits a distinguished photoluminescence peak related to recombination between the two-dimensional electron gas and photoexcited holes (2DEG-h), its crystal quality and rough surface morphology are poor. 2DEG mobility increases with the Al content up to 26% and then it apparently decreases for high Al-content (36%) AlGaN/GaN heterostructure. The increase of sheet carrier density with the increase of Al content has been observed. A high mobility at room temperature of 2105 cm 2 /V s with a sheet carrier density of n s = 1.10 × 10 13 cm -2 , for a 26% Al-content AlGaN/GaN heterostructure has been obtained, which is approaching state-of-the-art for HEMT grown on SiC. Sheet resistance as low as 274 Ω/□ has also been achieved.

关键词： AlGaN Hall-effect luminescence

A post-modification strategy to precisely construct dual-atom sites for oxygen reduction electrocatalysis

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Journal of Energy Chemistry 2024年第3期90卷 511-517,I0012页

作者： Juan wang Xinyan Liu Chang-Xin Zhao Yun-Wei Song jia-Ning Liu Xi-Yao Li chen-Xi Bi Xin Wan jianglan Shui hong-Jie Peng Bo-Quan Li jia-Qi Huang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China beijing Key laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Dual-atom catalysts(DACs) afford promising potential for oxygen reduction electrocatalysis due to their high atomic efficiency and high intrinsic ***,precise construction of dual-atom sites remains a *** this work,a post-modification strategy is proposed to precisely fabricate DACs for oxygen reduction ***,a secondary metal precursor is introduced to the primary single-atom sites to introduce direct metal-metal interaction,which ensures the formation of desired atom pair structure during the subsequent pyrolysis process and allows for successful construction of *** as-prepared FeCo-NC DAC exhibits superior oxygen reduction electrocatalytic activity with a half-wave potential of 0,91 V *** hydrogen ***-air batteries equipped with the FeCo-NC DAC demonstrate higher peak power density than those with the Pt/C *** importantly,this post-modification strategy is demonstrated universal to achieve a variety of dual-atom *** work presents an effective synthesis methodology for precise construction of catalytic materials and propels their applications in energy-related devices.

关键词： Dual-atom catalysts Electrocatalysis Oxygen reduction reaction Post-modification Zinc–air batteries

Reanalysis of energy band structure in the type-II quantum wells

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chinese physics B 2024年第6期33卷 75-78页

作者：李欣欣邓震江洋杜春花贾海强王文新陈弘 Key laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Materials and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China The Yangtze River Delta physics Research Center Liyang 213000China Songshan Lake Materials laboratory Dongguan 523808China

Band structure analysis holds significant importance for understanding the optoelectronic characteristics of semiconductor structures and exploring their potential applications in practice. For quantum well structures, the energy of carriers in the well splits into discrete energy levels due to the confinement of barriers in the growth direction. However, the discrete energy levels obtained at a fixed wave vector cannot accurately reflect the actual energy band structure. In this work, the band structure of the type-II quantum wells is reanalyzed. When the wave vectors of the entire Brillouin region(corresponding to the growth direction) are taken into account, the quantized energy levels of the carriers in the well are replaced by subbands with certain energy distributions. This new understanding of the energy bands of low-dimensional structures not only helps us to have a deeper cognition of the structure, but also may overturn many viewpoints in traditional band theories and serve as supplementary to the band theory of low-dimensional systems.

关键词： energy band structure type-II quantum wells low-dimensional semiconductors

Fulminant myocarditis induced by SARS-CoV-2 infection without severe lung involvement:insights into COvID-19 pathogenesis

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Journal of Genetics and Genomics 2024年第6期51卷 608-616页

作者： Han Du Zhongtao Du Liang wang hong wang Mingjun jia Chunge Zhang Yun Liu cheng Zhang Ya Zhang Ruifeng Zhang Shuang Zhang Ning Zhang Zhenghai Ma chen chen Wenjun Liu Hui Zeng George F.Gao Xiaotong Hou Yuhai Bi College of Life Science and Technology Xinjiang UniversityUrumchiXinjiang 830046China CAS Key laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyCenter for Influenza Research and Early-warning(CASCIRE)CAS-TWAS Center of Excellence for Emerging Infectious Diseases(CEEID)Chinese Academy of SciencesBeijing 100101China beijing Anzhen Hospital Capital Medical UniversityBeijing 100029China College of Veterinary Medicine Shanxi Agricultural UniversityTaiyuanShanxi 030031China University of chinese academy of sciences Beijing 100049China beijing Shijitan Hospital Capital Medical UniversityBeijing 100038China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection often leads to pulmonary *** sequelae,including myocarditis and heart failure,have also been ***,the study presents two fulminant myocarditis cases infected by SARS-CoV-2 exhibiting remarkable elevation of cardiac biomarkers without significant pulmonary injury,as determined by imaging *** staining reveals the viral antigen within cardiomyocytes,indicating that SARSCoV-2 could directly infect the *** full viral genomes from respiratory,anal,and myocardial specimens are obtained via next-generation *** analyses of the whole genome and spike gene indicate that viruses in the myocardium/pericardial effusion and anal swabs are closely related and cluster together yet diverge from those in the respiratory *** addition,unique mutations are found in the anal/myocardial strains compared to the respiratory strains,suggesting tissue-specific virus mutation and *** findings indicate genetically distinct SARS-CoV-2 variants have infiltrated and disseminated within myocardial tissues,independent of pulmonary injury,and point to different infection routes between the myocardium and respiratory tract,with myocardial infections potentially arising from intestinal *** findings highlight the potential for systemic SARS-CoV-2 infection and the importance of a thorough multi-organ assessment in patients for a comprehensive understanding of thepathogenesisof COVID-19.

关键词： COVID-19 SARS-CoV-2 Fulminant myocarditis Myocardium Infection

High-timing-precision detection of single X-ray photons by superconducting nanowires

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national Science Review 2024年第1期11卷 194-203页

作者： Shuya Guo Jingrou Tan Hengbin Zhang Jinguang wang Tianhao Ji Labao Zhang Xiaolong Hu jian chen Jun Xie Kai Zou Yun Meng Xiaomin Bei Ling-An Wu Qi chen Hao wang Xuecou Tu Xiaoqing jia Qing-Yuan Zhao Lin Kang Peiheng Wu Research institute of Superconductor Electronics Nanjing University Qian Xuesen laboratory of Space Technology beijing national laboratory of condensed matter physics Institute of Physics Chinese Academy of Sciences Hefei national laboratory School of Precision Instrument and Optoelectronic Engineering Tianjin University Key laboratory of Optoelectronic Information Science and Technology Ministry of Education

Precisely acquiring the timing information of individual X-ray photons is important in both fundamental research and practical applications. The timing precision of commonly used X-ray single-photon detectors remains in the range of one hundred picoseconds to microseconds. In this work, we report on high-timing-precision detection of single X-ray photons through the fast transition to the normal state from the superconductive state of superconducting nanowires. We successfully demonstrate a free-running X-ray single-photon detector with a timing resolution of 20.1 ps made of 100-nm-thick niobium nitride film with an active area of 50 μm by 50 μm. By using a repeated differential timing measurement on two adjacent X-ray single-photon detectors, we demonstrate a precision of 0.87 ps in the arrival-time difference of X-ray photon measurements. Therefore, our work significantly enhances the timing precision in X-ray photon counting, opening a new niche for ultrafast X-ray photonics and many associated applications.

关键词： single-photon detection timing precision superconductor ultrafast phenomenon pulsar X-ray navigation

Development of a High-throughput Sequencing Platform for Detection of Viral Encephalitis Pathogens Based on Amplicon Sequencing

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Biomedical and Environmental sciences 2024年第3期37卷 294-302页

作者： ZHANG Ya Li SU Wen Zhe wang Rui chen LI Yan ZHANG Jun Feng LIU Sheng Hui HU Dan He XU Chong Xiao YIN jia Yu YIN Qi Kai HE Ying LI Fan FU Shi hong NIE Kai LIANG Guo Dong TAO Yong XU Song Tao MA Chao Feng wang Huan Yu Shaanxi University of chinese Medicine Xianyang 712000ShaanxiChina national Key laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Guangzhou Center for Disease Control and Prevention Guangzhou 510000GuangdongChina Shandong Center for Disease Control and Prevention Jinan 250000ShandongChina Department of Ophthalmology Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China Xi'an Center for Disease Control and Prevention Xi’an 710054ShaanxiChina

Objective Viral encephalitis is an infectious disease severely affecting human *** is caused by a wide variety of viral pathogens,including herpes viruses,flaviviruses,enteroviruses,and other *** laboratory diagnosis of viral encephalitis is a worldwide ***,high-throughput sequencing technology has provided new tools for diagnosing central nervous system ***,In this study,we established a multipathogen detection platform for viral encephalitis based on amplicon *** We designed nine pairs of specific polymerase chain reaction(PCR)primers for the 12 viruses by reviewing the relevant *** detection ability of the primers was verified by software simulation and the detection of known positive *** sequencing was used to validate the samples,and consistency was compared with Sanger *** The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×,and the sequence lengths were consistent with the sizes of the predicted *** sequences were verified using the national Center for Biotechnology Information BLAST,and all results were consistent with the results of Sanger *** Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral *** is also a useful tool for the high-volume screening of clinical samples.

关键词： Viral encephalitis Amplicon sequencing High-throughput sequencing Multipathogen detection

Risk factors for renal outcomes in children with antineutrophil cytoplasmic antibody-associated vasculitis:a nationwide retrospective study in china

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World Journal of Pediatrics 2024年第5期20卷 506-516页

作者： Li-Wen Tan Jun-Li Wan Chun-Hua Zhu hong Xu Zheng-Kun Xia Li-Zhi chen Xiao-Chuan Wu Fang wang Xiao-Rong Liu cheng-Guang Zhao Xiao-Zhong Li jian-Hua Mao Xiao-Wen wang Wen-Yan Huang Yu-hong Li jian-jiang Zhang Shi-Pin Feng Jun Yang jiao-jiao Liu Chun-Lin Gao Li-Ping Rong Lan-Jun Shuai Ke Xu He-jia Zhang Qiu Li Ai-Hua Zhang Mo wang Department of Nephrology Children’s Hospital of Chongqing Medical UniversityZhongshan 2nd Rd.136Chongqing400014China Ministry of Education Key laboratory of Child Development and Disorders National Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren’s Hospital of Chongqing Medical UniversityChongqingChina Chongqing Key laboratory of Pediatrics Children’s Hospital of Chongqing Medical UniversityChongqingChina Department of Nephrology Children’s Hospital of Nanjing Medical University72 Guangzhou RoadNanjing210008China Department of Nephrology Children’s Hospital of Fudan UniversityNational Paediatric Medical Center of ChinaShanghaiChina Department of Pediatrics Jinling HospitalNanjing Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalThe First School of Clinical MedicineSouthern Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalMedical School of Nanjing UniversityNanjingChina Department of Pediatric Nephrology and Rheumatology The First Affiliated Hospital of Sun Yat-Sen UniversityGuangzhouChina Department of Pediatrics The Second Xiangya Hospital of Central South UniversityChangshaChina Department of Pediatrics Peking University First HospitalBeijingChina Department of Nephrology Beijing Children’s HospitalCapital Medical UniversityBeijing100045China national Center for Children’s Health BeijingChina Department of Pediatrics Shengjing Hospital of China Medical UniversityShenyangChina Department of Nephrology and Immunology Children’s Hospital of Soochow UniversitySuzhouChina Department of Nephrology Children HospitalZhejiang University School of MedicineHangzhouChina Department of Nephrology Wuhan Children’s Hospital(Wuhan Maternal and Child Healthcare Hospital)Tongji Medical CollegeHuazhong University of Science&TechnologyWuhanChina Department of Nephrology and Rheumatology Shanghai Children’s HospitalSchool

Background Pediatric antineutrophil cytoplasmic antibody-associated vasculitis(AAV)is a life-threatening systemic vasculitis featured by liability to renal ***,there are few studies on the risk factors and predictive models for renal outcomes of AAV in *** Data from 179 AAV children in multiple centers between January 2012 and March 2020 were collected *** risk factors and predictive model of end-stage renal disease(ESRD)in AAV were *** Renal involvement was the most typical manifestation(95.5%),and the crescent was the predominant pathological lesion(84.9%).The estimated glomerular filtration rate(eGFR)was evaluated in 114 patients,of whom 59.6%developed ESRD,and the median time to ESRD was 3.20 *** eGFR[P=0.006,odds ratio(OR)=0.955,95%confidence interval(CI)=0.924–0.987]and the percentages of global glomerulosclerosis(pGGS;P=0.018,OR=1.060,95%CI=1.010–1.112)were independent risk factors for ESRD of renal *** on the pGGS and eGFR at renal biopsy,we developed three risk grades of ESRD and one predictive *** Kaplan‒Meier curve indicated that renal outcomes were significantly different in different risk grades(P china,of which more than half deteriorates into *** predictive model based on eGFR at renal biopsy and the pGGS may be stable and accurate in speculating the risk of ESRD in AAV children.

关键词： Antineutrophil cytoplasmic antibody End-stage renal disease Glomerulonephritis Pediatric nephrology Vasculitis

Amelioration of habitat since the early Holocene contributed to the origin of agriculture in the farming-pastoral zone of northern china

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Science china Earth sciences 2024年第8期67卷 2535-2546页

作者： Xin jia Zhiping ZHANG Yonggang SUN Runqi jiaNG Shuangwen YI Wei chen Jue SUN Guoqiang LI Shuzhi wang Enrui LI Xiaonong HU Qingchun BAO Harry F.LEE Huayu LU jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Schlool of History and Culture Chifeng UniversityChifeng 024000China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China State Key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Key laboratory of Western china’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China institute of Archaeology Chinese Academy of Social SciencesBeijing 100710China Ulanqab Museum Ulanqab 012000China The institute of Cultural Relics and Archaeology Hohhot 010011China Department of Geography and Resource Management The Chinese University of Hong KongHong Kong 999077China Key laboratory of Virtual Geographic Environment(Ministry of Education of PRC) Nanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China institute of Environmental Archaeology Nanjing Normal UniversityNanjing 210023China

The origin of agriculture in the farming-pastoral zone of northern china remains in *** central region of the Inner Mongolia Plateau is located in the core area of the farming-pastoral zone;thus,it is a critical region for exploring the origin of the dryland farming system in northern *** study selected the Yumin Site and Banan Site,which belong to the Yumin Culture-the beginning of Neolithic culture in Inner Mongolia-as the research *** on the quartz optically stimulated luminescence(OSL)dating on the sedimentary sections from the Yumin site(YM)and Banan site(BN1 and BN2),the Holocene chronology framework of each section was *** that,by identifying carbonized grains in the Yumin site and the multi-proxy analysis of each section,we investigated the relationship between the origin of agriculture and climate change in this *** results revealed that the timing of the origin of agriculture recorded in the Yumin site lagged behind the timing of a significant increase of precipitation during the early Holocene but coincided with the timing of a significant increase of vegetation around 8.4 *** phenomenon was further confirmed by the published high-resolution paleoenvironmental records from the surrounding area of the Yumin *** propose that with the gradual amelioration of hydrothermal conditions since the beginning of the Holocene,the regional ecosystem had been improved,resulting in the gradual conversion of the land surface from infertile sand to organic-rich soil,providing an appropriate environmental foundation for the origin of dryland farming in northern china around 8.4 *** study highlighted that the“accumulative environmental effects”during the early Holocene played a vital role in the origin of agriculture in northern china and provided a reference for agricultural management in the context of future climate change.

关键词： Origin of agriculture Accumulative environmental effects Yumin Culture Northern china Holocene