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| 1 | An Overview of Terahertz Antennas显示文摘The terahertz(THz)antennas,which have features of small size,wide frequency bandwidth and high data rate,are important devices for transmitting and receiving THz electromagnetic waves in the emerging THz systems.However,most of THz antennas suffer from relatively high loss and low fabrication precision due to their small sizes in high frequency bands of THz waves.Therefore,this paper presents a detailed overview of the most recent research on the performance improvement of THz antennas.Firstly,the development of THz antennas is briefly reviewed and the basic design ideas of THz antennas are introduced.Then,THz antennas are categorized as metallic antennas,dielectric antennas and new material antennas.After that,the latest research progress in THz photoconductive antennas,THz horn antennas,THz lens antennas,THz microstrip antennas and THz on-chip antennas are discussed.In particular,the practical difficulties for the development of THz antennas are discussed with promising approaches.In addition,this paper also presents a short review of the process technology of THz antennas.Finally,the vital challenges and the future research directions for THz antennas are presented. | Yejun He Yaling Chen Long Zhang Sai-Wai Wong Zhi Ning Chen | 2020 | China Communications2020，17，7： | 6 |
| 2 | Postsynthesis of hierarchical core/shell ZSM-5 as an efficient catalyst in ketalation and acetalization reactions显示文摘Hierarchical core/shell Zeolite Socony Mobil-five(ZSM-5)zeolite was hydrothermally postsythesized in the solution of NaOH and diammonium surfactant via a dissolution-reassembly strategy.The silica and alumina species were firstly dissolved partially from the bulky ZSM-5 crystals and then were reassembled into the MFI-type nanosheets with the structure-directing effect of diammonium surfactant,attaching to the out-surface of ZSM-5 core crystals.The mesopores thus were generated in both the core and shell part,giving rise to a micropore/mesopore composite material.The micropore volume and the acidity of the resultant hybrid were well-preserved during this recrystallization process.Possessing the multiple mesopores and enlarged external surface area,the core/shell ZSM-5 zeolite exhibited higher activity in the ketalation and acetalization reactions involving bulky molecules in comparison to the pristine ZSM-5. | Peng Luo Yejun Guan Hao Xu Mingyuan He Peng Wu | 2020 | Frontiers of Chemical Science and Engineering2020，14，2： | 3 |
| 3 | A surveyof energy harvesting communications : models and offlineoptimal policies 显示文摘 | He Yejun Cheng Xudong Peng Wei | 2015 | IEEE Communications Magazine2015，53，6： | 1 |
| 4 | Study of Magnetic Field Coupling Technologies in Activating RFID-SIM Card Mobile Payments显示文摘 | Yejun He | 2013 | Wireless Personal Communications2013，，1： | 1 |
| 5 | X-ray spectrometry using polyeapillary X-ray optics and position sensitive detector显示文摘 | Ding Xun-liang Xie Jing-dong He Yejun | 2000 | Talanta2000，53，： | 1 |
| 6 | X-ray spectrometry using polycapillary X-ray optics and position sensitive detector显示文摘 | Ding Xunliang Xie Jingdong He Yejun | 2000 | Talanta2000，53，： | 1 |
| 7 | X-ray spectrometry using polycapillary X-ray optics and position sensitive detector 显示文摘 | Ding Xunliang Xie J D He Yejun | 2000 | Talanta2000，53，： | 1 |
| 8 | X-ray spectrometry using polycapillary X-ray optics and position sensitive detector显示文摘 | Ding Xunliang Xie Jingdong He Yejun | 2000 | Talanta2000，53，： | 1 |
| 9 | X-ray lens of monolithic polycapillaries for macromolecular crystallography显示文摘 | He Yejun Chen Jun Li Yude | 1998 | Journal of X-ray Science and Technology1998，8，： | 1 |
| 10 | Green carbon science:fundamental aspects显示文摘Carbon energy has contributed to the creation of human civilization,and it can be considered that the configuration of the carbon energy system is one of the important laws that govern the operation of everything in the universe.The core of the carbon energy system is the opposition and unity of two aspects:oxidation and reduction.The operation of oxidation and reduction is based on the ternary elemental system composed of the three elements of carbon,hydrogen and oxygen.Its operation produces numerous reactions and reaction products.Ancient Chinese philosophy helps us to understand in depth the essence of green carbon science,to explore its scientific basis,and to identify the related platforms for technology development. | Mingyuan He Kun Zhang Yejun Guan Yuhan Sun Buxing Han | 2023 | National Science Review2023，10，9： | 1 |
| 11 | Turbo Product Codes and Their Application in the 4th Generation Mobile Communication System显示文摘 | HE Yejun ZHUGuangxi LIU Yingzhuang | 2003 | Proceedings of SPIE2003，，5284： | 1 |
| 12 | Risk stratification system for skin and soft tissue infections after allogeneic hematopoietic stem cell transplantation:PAH risk score显示文摘Skin and soft tissue infections(SSTIs)refer to infections involving the skin,subcutaneous tissue,fascia,and muscle.In transplant populations with hematological malignancies,an immunocompromised status and the routine use of immunosuppressants increase the risk of SSTIs greatly.However,to date,the profiles and clinical outcomes of SSTIs in hematopoietic stem cell transplantation(HSCT)patients remain unclear.This study included 228 patients(3.67%)who developed SSTIs within 180 days after allogeneic HSCT from January 2004 to December 2019 in Peking University People’s Hospital.The overall annual survival rate was 71.5%.We compared the differences between survivors and non-survivors a year after transplant and found that primary platelet graft failure(PPGF),comorbidities of acute kidney injury(AKI),and hospital-acquired pneumonia(HAP)were independent risk factors for death in the study population.A PPGF-AKI-HAP risk stratification system was established with a mortality risk score of 1×PPGF+1×AKI+1×HAP.The areas under the curves of internal and external validation were 0.833(95%CI 0.760–0.906)and 0.826(95%CI 0.715–0.937),respectively.The calibration plot revealed the high consistency of the estimated risks,and decision curve analysis showed considerable net benefits for patients. | Shan Chong Yun He Yejun Wu Peng Zhao Xiaolu Zhu Fengrong Wang Yuanyuan Zhang Xiaodong Mo Wei Han Jingzhi Wang Yu Wang Huan Chen Yuhong Chen Xiangyu Zhao Yingjun Chang Lanping Xu Kaiyan Liu Xiaojun Huang Xiaohui Zhang | 2022 | Frontiers of Medicine2022，16，6： | 0 |
| 13 | Highly Emissive Luminogens in Both Solution and Aggregate States显示文摘Organic light-emitting materials have attracted considerable attention because of their promising applications in diverse areas.Most fluorophores emit brightly in either dilute solutions or aggregate states;the former generally suffer from aggregation-caused quenching problem,and the latter encounter intensity loss at low concentrations.Herein,we propose a new strategy to overcome these dilemmas by balancing the planar and distorted structures of terphenyl-based luminogens and obtain three luminogens,2PB-AC,2Me2PB-AC,and 2T2PB-AC,with bright emission in both solution and aggregate states.Among them,2PB-AC shows absolute photoluminescence quantum yields(ФPL)higher than 90%in both tetrahydrofuran solution(90.2%)and aggregate states(92.7%for powder and 95.3%for crystal).Thus,2PB-AC could be an efficient probe to realize dual-channel explosive detection in both solution and aggregate states.Moreover,it could be used to image live-cell lipid droplets at a wide range of concentrations.In addition,benefiting from its thermodynamically favorable intersystem crossing process,2Me2PB-AC could be doped in polymethyl methacrylate matrix to provide efficient room-temperature phosphorescence.Thus,this work provides a feasible strategy for the design of luminogens with highly efficient emission in both solution and aggregate states,greatly facilitating and broadening their practical applications. | Pengbo Han Guiquan Zhang Jia Wang Yejun Yao Yanping Qiu He Xu Anjun Qin Ben Zhong Tang | 2023 | CCS Chemistry2023，5，7： | 0 |
| 14 | Solvent-stabilized few-layer violet phosphorus and its ultrafast nonlinear optics显示文摘Featured with high thermal decomposition temperature and layered structure,violet phosphorus(VP)offers an unparalleled stable allotrope of phosphorus to demonstrate the optoelectronic device and photonics elements with high performance at the nanoscale.Here,we report few-layer and hundreds of nanometer-sized VP with robust stability in different solvents and ambient conditions by ultrasound-assisted liquid phase exfoliation approach.For the first time,the ultrafast carrier dynamics and thirdorder nonlinear optical response of VP were investigated.Sub-picosecond timescale ultrafast carrier dynamic and ultrafast nonlinear saturable absorption of VP were demonstrated.Our findings demonstrated that VP possessed a promising potential for use in ultrafast nonlinear photonic applications such as saturable absorbers and optical switches. | Li Zhou Jianlong Kang Yulan Dong Yiduo Wang Yejun Li Han Huang Si Xiao Yingwei Wang Jun He | 2023 | Nano Research2023，16，4： | 0 |
| 15 | A New Scheme of Bit-plane Coding in MPEG-4显示文摘 | Feng Wang Guangxi Zhu Zhenming Zhang Yejun He | 2005 | 通讯和计算机(中英文版)2005，2，5： | 0 |
| 16 | 代谢成像揭示白血病起始细胞归巢于骨内膜微环境并有效对称分裂的独特偏好显示文摘文章简介白血病起始细胞(leukemia-initiatingcells,LICs)在不同骨髓微环境中的代谢特征及其与细胞命运决定的关系尚不清楚。研究团队利用遗传编码的高度灵敏的NADH/NAD+代谢感受器(So Nar)标记和指示小鼠和患者白血病细胞代谢状态,构建了实时在体代谢成像体系,并阐明了白血病细胞中存在明显的代谢异质性。 | Xiaoxin Hao Hao Gu Chiqi Chen Dan Huang Yuzheng Zhao Li Xie Yejun Zou Hui Sophie Shu Yaping Zhang Xiaoxiao He Xiaoyun Lai Xiaocui Zhang Bo OZhou Cheng Cheng Zhang Guo-Qiang Chen 于卓 杨弋 郑俊克 | 2020 | 科学新闻2020，，2： | 0 |
| 17 | A Compact Ultra-Wideband Circularly Polarized Antenna Array for Vehicular Communications显示文摘In this paper,a new compact ultrawideband(UWB)circularly polarized(CP)antenna array for vehicular communications is proposed.The antenna array consists of a 2×2 sequentially rotated T-shaped cross dipole,four parasitic elements,and a feeding network.By loading the T-shaped cross dipoles with parasitic rectangular elements with cut corners,the bandwidth can be expanded.On this basis,the radiation pattern can be improved by the topology with sequential rotation of four T-shaped cross-dipole antennas,and the axial ratio(AR)bandwidth of the antenna also can be further enhanced.In addition,due to the special topology that the vertical arms of all Tshaped cross dipoles are all oriented toward the center of the antenna array,the gain of proposed antenna is improved while the size of the antenna is almost the same as the traditional cross dipole.Simulated and measured results show that the proposed antenna has good CP characteristics,an impedance bandwidth for S11<-10 d B of about 106.1%(3.26:1,1.57-5.12 GHz)and the 3-d B AR bandwidth of about 104.1%(3.17:1,1.57-4.98 GHz),a wide 3-d B gain bandwidth of 73.3%as well as the peak gain of 8.6 d Bic at 3.5 GHz.The overall size of antenna is 0.56λ×0.56λ×0.12λ(λrefers to the wavelength of the lowest operating frequency in free space).The good performance of this compact UWB CP antenna array is promising for applications in vehicular communications. | Wei He Yejun He Long Zhang Jun Hong Haixia Cui Amir Boag | 2023 | China Communications2023，20，6： | 0 |
| 18 | A Survey on Channel Measurements and Models for Underground MIMO Communication Systems显示文摘The high reliability of the communication system is critical in metro and mining applications for personal safety,channel optimization,and improving operational performance.This paper surveys the progress of wireless communication systems in underground environments such as tunnels and mines from 1920 to 2022,including the evolution of primitive technology,advancements in channel modelling,and realization of various wireless propagation channels.In addition,the existing and advanced channel modeling strategies,which include the evolution of different technologies and their applications;mathematical,analytical,and experimental techniques for radio propagation;and significance of the radiation characteristics,antenna placement,and physical environment of multiple-input multiple-output(MIMO)communication systems,are analyzed.The given study introduces leaky coaxial cable(LCX)and distributed antenna system(DAS)designs for improving narrowband and wideband channel capacity.The paper concludes by figuring out open research areas for the future technologies. | Asad Saleem Yejun He Guoxin Zheng Zhining Chen | 2023 | China Communications2023，20，8： | 0 |
| 19 | 2D Nb_(2)CT_(x) MXene/MoS_(2) heterostructure construction for nonlinear optical absorption modulation显示文摘Two-dimensional(2D)nonlinear optical mediums with high and tunable light modulation capability can significantly stimulate the development of ultrathin,compact,and integrated optoelectronics devices and photonic elements.2D carbides and nitrides of transition metals(MXenes)are a new class of 2D materials with excellent intrinsic and strong light-matter interaction characteristics.However,the current understanding of their photo-physical properties and strategies for improving optical performance is insufficient.To address this issue,we rationally designed and in situ synthesized a 2D Nb_(2)C/MoS_(2) heterostructure that outperforms pristine Nb2C in both linear and nonlinear optical performance.Excellent agreement between experimental and theoretical results demonstrated that the Nb_(2)C/MoS_(2) inherited the preponderance of Nb_(2)C and MoS_(2) in absorption at different wavelengths,resulting in the broadband enhanced optical absorption characteristics.In addition to linear optical modulation,we also achieved stronger near infrared nonlinear optical modulation,with a nonlinear absorption coefficient of Nb_(2)C/MoS_(2) being more than two times that of the pristine Nb_(2)C.These results were supported by the band alinement model which was determined by the X-ray photoelectron spectroscopy(XPS)experiment and first-principal theory calculation.The presented facile synthesis approach and robust light modulation strategy pave the way for broadband optoelectronic devices and optical modulators. | Yiduo Wang Yingwei Wang Yulan Dong Li Zhou Jianlong Kang Ning Wang Yejun Li Xiaoming Yuan Zhengwei Zhang Han Huang Mengqiu Long Si Xiao Jun He | 2023 | Opto-Electronic Advances2023，6，10： | 0 |
| 20 | Efficient synthesis of bioetheric fuel additive by combining the reductive and direct etherification of furfural in one-pot over Pd nanoparticles deposited on zeolites显示文摘Furfuryl ethers have been considered to be a promising fuel additive.One step reduction etherification of furfural over supported Pd catalysts provides a facile way for the preparation of furfuryl ether.However,the preparation of a reusable Pd catalyst for reductive etherification remains to be a great challenge.In this study,a series of Si O_(2)supported Pd catalysts with particle size ranging from 2.2 nm to 28 nm were prepared.Their textural properties and catalytic performance in furfural reductive etherification have been systematically studied.The results herein shed light on the particle size effect on the competition between hydrogenation/hydrogenolysis of C=O in furfural over Pd surface.We found out that Pd nanoparticles larger than 3 nm are preferred for one step reductive etherification.Based on this finding,we prepared a Pd/ZSM-5 bifunctional catalyst comprising Pd nanoparticles larger than 3 nm and decreased acidity in presence of amino organosilane,which served as a bifunctional catalyst succeeding in one-pot synthesis of ether via reductive-etherification and direct-etherification.This strategy showed significant advantage in efficiently converting furfuryl acohol,a major side-product,into ether,while suppressing the undesired side-reactions. | Xiaowen Guo Haihong Wu Peng Wu Mingyuan He Yejun Guan | 2023 | Green Energy & Environment2023，8，2： | 0 |
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