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Controlled fabrication, lasing behavior and excitonic recombination dynamics in single crystal CH3NH3PbBr3 perovskite cuboids

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Science Bulletin 2019年第10期64卷 698-704页

作者： Fangtao Li Junfeng Lu qinglin zhang Dengfeng Peng Zheng Yang Qian Xu Caofeng Pan Anlian Pan Tianfeng Li Rongming Wang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science School of Mathematics and Physics University of Science and Technology Beijing Beijing 100083 China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and Sensor Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 100083 China School of Nanoscience and Technology University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory for Micro-Nano Physics and Technology of Hunan Province Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education College of Materials and Engineering Hunan University Changsha 410082 China College of Optoelectronic Engineering Shenzhen University Shenzhen 518060 China School of Physics and Electronics Henan University Kaifeng 475004 China

As a direct bandgap semiconductor, organic-inorganic lead halide perovskite (MAPbX3, MA = CH3NH3, X =Cl, Br, I) have been considered as promising materials for laser due to their excellent optoelectronic properties. The perovskite materials with ID and 2D shapes were widely prepared and studied for Fabry-Perot mode and whispering-gallery-mode (WGM) microcavities, but cuboid-shape is rarely reported. In this work, we successfully fabricated single crystal cuboid-shaped MAPbBr3 perovskite w让h different morphologies, named microcuboid-MAPbBr3 (M-MAPbBr3) and multi-step-MAPbBr3 (MSMAPbBr3), via solvothermal method. Furthermore, the as-prepared *crystals excitonic recombination lifetime under different pumping energy density was studied by time-resolved photoiuminescence (TRPL). Based on controllable morphology and remarkable lasing properties, these cuboid shaped single crystal perovskite could be a promising candidate for small laser, and other optoelectronic devices.

关键词： Lead halide perovskite Solvothermal method Single crystal cuboid Lasing TRPL

Cesium lead halide perovskite triangular nanorods as high-gain medium and effective cavities for multiphoton- pumped lasing

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Nano Research 2017年第10期10卷 3385-3395页

作者： Xiaoxia Wang Hong Zhou Shuangping Yuan Weihao Zheng Ying Jiang Xiujuan Zhuang Hongjun Liu qinglin zhang Xiaoli Zhu Xiao Wang Anlian Pan School of Physics and Electronics Key Laboratory for Micro-Nano Physics and Technology of Hunan Province and State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha 410082 China Institute of Physical and Theoretical Chemistry University of Tübingen Aufder Morgenstelle 18 72076 Tübingen Germany

High-performance multiphoton-pumped lasers based on cesium lead halide perovskite nanostructures are promising for nonlinear optics and practical frequency upconversion devices in integrated photonics. However, the performance of such lasers is highly dependent on the quality of the material and cavity, which makes their fabrication challenging. Herein, we demonstrate that cesium lead halide perovskite triangular nanorods fabricated via vapor methods can serve as gain media and effective cavities for multiphoton-pumped lasers. We observed blue-shifts of the lasing modes in the excitation fluence-dependent lasing spectra at increased excitation powers, which fits well with the dynamics of Burstein-Moss shifts caused by the band filling effect. Moreover, efficient multiphoton lasing in CsPbBr3 nanorods can be realized in a wide excitation wavelength range （700-1,400 nm）. The dynamics of multiphoton lasing were investigated by time-resolved photoluminescence spectroscopy, which indicated that an electron-hole plasma is responsible for the multiphoton-pumped lasing. This work could lead to new opportunities and applications for cesium lead halide perovskite nanostructures in frequency upconversion lasing devices and optical interconnect systems.

关键词： cesium lead halide perovskite nanorods triangular cross-section multiphoton-pumped laser time-resolved photoluminescence

Edge assisted epitaxy of CsPbBr_(3)nanoplates on Bi_(2)O_(2)Se nanosheets for enhanced photoresponse

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Chinese Physics B 2022年第4期31卷 693-699页

作者： Haotian Jiang Xing Xu Chao Fan Beibei Dai Zhuodong Qi Sha Jiang Mengqiu Cai qinglin zhang Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha 410082China

Bi_(2)O_(2)Se has been proved to be a promising candidate for electronic and optoelectronic devices due to their unique physical ***,it is still a great challenge to construct the heterostructures with direct epitaxy of hetero semiconductor materials on Bi_(2)O_(2)Se ***,a two-step chemical vapor deposition(CVD)route was used to directly grow the CsPbBr_(3)nanoplate-Bi_(2)O_(2)Se nanosheet hetero *** CsPbBr_(3)nanoplates were selectively grown on the Bi_(2)O_(2)Se nanosheet along the edges,where the dangling bonds provide the nucleation *** epitaxial relationships between CsPbBr3 and Bi_(2)O_(2)Se were determined as[200]_(Bi_(2)O_(2)Se)‖[110]_(CsPbBr_(3))and[110]_(Bi_(2)O_(2)Se)‖[200]_(CsPbBr_(3))by transmission electron microscopy *** photoluminescence(PL)results reveal that the formation of heterostructures results in the remarkable PL quenching due to the type-Ⅰband arrangement at CsPbBr_(3)/Bi_(2)O_(2)Se interface,which was confirmed by ultraviolet photoelectron spectroscopy(UPS)and Kelvin probe measurements,and makes the photogenerated carriers transfer from CsPbBr_(3)to Bi_(2)O_(2)***,the photodetectors based on the heterostructures exhibit a 4-time increase in the responsivity compared to those based on the pristine Bi_(2)O_(2)Se sheets,and the fast rise and decay time in *** results indicate that the direct epitaxy of the CsPbBr_(3)plates on the Bi_(2)O_(2)Se sheet may improve the optoelectronic performance of Bi_(2)O_(2)Se based devices.

关键词： Bi_(2)O_(2)Se heterostructures photogenerated carriers photoresponse

Synthesis and Diameter-dependent Thermal Conductivity of InAs Nanowires

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Nano-Micro Letters 2014年第4期6卷 301-306页

作者： Pinyun Ren Xiaoli Zhu Jinyun Han Jinyou Xu Liang Ma Honglai Li Xiujuan Zhuang Hong Zhou qinglin zhang Minggang Xia Anlian Pan Key Laboratory for Micro-Nano Physics and Technology of Hunan Province State Key Laboratory of Chemo/Biosensing and Chemometrics College of Physics and Microelectronics Science Hunan University Condensed Matter Physics Laboratory Center on Experimental Physics School of Science Xi’an Jiaotong University

In this work, we synthesized high-quality In As nanowires by a convenient chemical vapor deposition method,and developed a simple laser heating method to measure the thermal conductivity of a single In As nanowire in air. During the measurement, a focused laser was used to heat one end of a freely suspended nanowire, with its other end embedded into a carbon conductive adhesive. In order to obtain the thermal conductivity of In As nanowires, the heat loss in the heat transfer process was estimated, which includes the heat loss through air conduction, the heat convection, and the radiation loss. The absorption ratio of the laser power in the In As nanowire was calculated. The result shows that the thermal conductivity of In As nanowires monotonically increases from 6.4 W m-1K-1to 10.5 W m-1K-1with diameters increasing from 100 nm to 190 nm, which is ascribed to the enhanced phonon-boundary scattering.

关键词： InAs nanowires Chemical vapor deposition Thermal conductivity Phonon-boundary scattering

The automatic processes of earthquake-related stimulus: Comparison at different time points after the Wenchuan earthquake

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Natural Science 2013年第8期5卷 925-932页

作者： Ming Lei Jiang Qiu qinglin zhang Key Laboratory of Personality and Cognition Ministry of Education Southwest University Chongqing China Faculty of Psychology Southwest University Chongqing China Psychological Research and Counseling Center Southwest Jiaotong University Chengdu China

Trauma experience not only could predict long-term physical and mental health problems, but also could have impact on the cognitive processes. Modified Stroop task and subliminal masked priming task were used to examine the automatic cognitive processing of earthquake-related stimulus (disaster-related, rescue-related, and earthquake-unrelated words) of healthy undergraduates at one month and two years since the Wenchuan earthquake happened, who came from the worst-hit areas of the Wenchuan earthquake. The results showed that the earthquake interference effects were showed in modified Stroop task and reversed priming effects were found in subliminal masked priming task at one month after the Wenchuan earthquake. However, two years later, earthquake interference effects and reversed priming effects were not found in the same experiments. The results showed the automatic cognitive processing of healthy subjects experienced trauma was affected by the earthquake episodic memory, and these interference effects were weakened with the passage of time.

关键词： The Wenchuan Earthquake Stroop Effect Subliminal Masked Priming

High-Speed Parallel Matched Filter Designing and FPGA Implementation

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Wuhan University Journal of Natural Sciences 2010年第4期15卷 335-339页

作者： zhang qinglin, CHEN Shuzhen, LUO Yijun, WANG Shan School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China School of Electronic Information Wuhan University Wuhan Hubei China

Matched filter is one of the key technologies to achieve high-speed data transmission. In this paper,a parallel finite-impulse response (FIR) filter structure based on polyphase filter-ing is used to achieve high-speed matched filter in quadrature phase-shift keying (QPSK) demodulation up to 800 Mb·s-1. First,a window function is employed of to obtain impulse response of matched filter. Second,the high-speed parallel FIR structure is presented based on polyphase filtering. Then,the filter with EP2S180F1020 on the Quartus II 7.2 platform is achieved. The final results show that the design is correct and can implement high-speed matched filtering,wherein the equivalent frequency of which is up to 2 037 MHz. In addition,this scheme is easy to real-ize,which brings great value to the application of this filter in high-speed matched filters design in demodulation systems.

关键词： parallel matched filter finite-impulse response (FIR) window function polyphase filtering field programmable gate array

Diagnosis of brain death： confirmatory tests after clinical test

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Chinese Medical Journal 2014年第7期127卷 1272-1277页

作者： Su Yingying Yang qinglin Liu Gang zhang Yan Ye Hong Gao Daiquan zhang Yunzhou Chen Weibi Department of Neurocritical Care Unit Xuanwu Hospital Capital Medical University Beijing 100053 China

Background The brain death confirmation tests occupy a different position in each country＇s diagnostic criteria （or guideline）; the choices of tests are also *** brain death criteria include clinical judgment and confirmation *** study aimed to confirm the preferred confirmatory test and complementary confirmatory *** We did a clinical brain death determination on deep coma patients,and then divided them into brain death group and non-brain death *** to the Chinese standards for determining brain death,both the groups accepted confirmatory tests including electroencephalograph （EEG）,somatosensory evoked potentials （SEP）,and transcranial Doppler （TCD）.The sensitivity,specificity,false positive rate,and false negative rate were calculated to evaluate the accuracy of the confirmatory *** Among the 131 cases of patients,103 patients met the clinical criteria of brain *** arrest provocation test was performed on 44 cases and 32 cases （73％） successfully completed and confirmed that they have no spontaneous *** the three confirmation tests,EEG had the highest completion rate （98％） and good sensitivity （83％） and specificity （97％）; TCD had followed completion rate （54％） and not good sensitivity （73％） and specificity （75％）; SEP had the lowest completion rate （49％）,good sensitivity （100％）,and not good specificity （78％）.After the combination of SEP or TCD with EEG,the specificity can increase to 100％.Conclusions The completion rate of respiratory arrest provocation test remains a problem in the clinical diagnosis of brain *** the test cannot be completed,whether to increase a confirmatory test is *** had an ideal sensitivity,and the specificity will reach 100％ after combining with TCD or *** a confirmed test was uncertain,we suggest increasing another confirmatory test.

关键词： brain death clinical diagnosis confirmatory tests electroencephalograph somatosensory evoked potentials transcranial Doppler

Androecious Genotype ‘Male 8' Carries the CPCNA Gene Locus Controlling Natural Deastringency of Chinese PCNA Persimmons

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Horticultural Plant Journal 2016年第6期2卷 309-314页

作者： zhang Na XU Junchi MO Rongli zhang qinglin LUO Zhengrong Key Laboratory of Horticultural Plant Biology Huazhong Agricultural University Hubei Collaborative Innovation Center for the Characteristic Resources Exploitation of Dabie Mountains Huanggang Normal University

The androecious genotype of Diospyros spp. ‘Male 8', which is distributed in Dabie Mountain area of the central China, was probably derived from the hybrids or natural variation of Chinese pollination constant and non-astringent(CPCNA) persimmon. Its application potential as the breeding parent of pollination constant and non-astringent(PCNA) is undefined. In this study, we identified the astringency type of a hybrid individual(H8-2) derived from the cross between ‘Huashi 1'(pollination variant and astringent, PVA) and ‘Male 8'. Through comparison with the known genotypes of CPCNA, Japanese PCNA(JPCNA) and non-PCNA, the results of soluble/insoluble tannin content and tannin cell size measure showed that H8-2 was a PCNA genotype with the characteristic of natural deastringency of CPCNA. According to the currently known genetic features of PCNA persimmon, a new individual of PCNA may be generated in F1 population when two JPCNA genotypes are crossed or when the CPCNA genotype is used as a parent. Thus, the study verifies that androecious genotype ‘Male 8' carries the dominant gene locus that controls the non-astringent trait of CPCNA, indicating its potential to be used as pollen donor for the genetic improvement of PCNA persimmon.

关键词： Chinese androecious persimmon PCNA soluble tannin content tannin cell size genetic improvement

阳极产生苯炔中间体与环状β-酮羰基化合物的催化不对称电化学α-芳基化反应

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有机化学 2020年第11期40卷 3978-3979,M0016页

作者：张庆林郭昌中国科学技术大学合肥微尺度物质科学国家研究中心合肥230026

自1830年法拉第完成第一个制备性有机电化学实验——乙酸电解实验以来[1],电化学以其对有机化合物独特的氧化还原能力而被广泛的应用在有机合成中,其避免有毒有害的氧化还原试剂的使用、对化合物某一位点可进行选择性的氧化还原、可原... 详细信息

自1830年法拉第完成第一个制备性有机电化学实验——乙酸电解实验以来[1],电化学以其对有机化合物独特的氧化还原能力而被广泛的应用在有机合成中,其避免有毒有害的氧化还原试剂的使用、对化合物某一位点可进行选择性的氧化还原、可原位产生不稳定及危险试剂等优势,得到了科研工作者的广泛关注,并逐渐发展为有机化学中的一个重要分支[2].

关键词：氧化还原能力芳基化反应有机电化学有机化学法拉第有机化合物有机合成苯炔