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Science China Chemistry 2023年第5期66卷 1384-1393页

作者： Yi-Fan sun Ya-Jie Liu San-Tai wang Xiao-Yu Liu Chao Ma Wei-Hui fang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Based on our discovery of neutral aluminum molecular rings,we herein introduce rare earth ions into the center of the ring and reveal their structural *** resulting yoyo-like cationic macrocycles are highly adaptive to guests,creating unusual supramolecular *** first category is stacked with singly oriented rhombohedral channels,which exhibit fast and reversible solvent-triggered molecular motions and structural *** second type of assembly is that yoyo macrocycles and guest molecules form a nested host-guest sodalite cage supramolecular *** is uncommon for guest molecules to be well-defined within cages although caged structures have been *** host-guest interaction discussion reveals the self-adaptation and flexibility of the yoyo *** their good water stability,we investigated their anion exchange *** results show that they have significant exchange capacity for KI/I_(2),ReO_(4)^(-),and MnO_(4)^(-),revealing their potential application in water purification and nuclear waste treatment.

关键词： aluminum molecular ring lanthanide structural adaptability sodalite cage iodine capture

High Diversity in Genotypes of Human Rhinovirus Contributes to High Prevalence in Beijing,2018-2022:A Retrospective Multiple-Center Epidemiological Study

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Biomedical and Environmental Sciences 2024年第11期37卷 1262-1272页

作者： Qing wang Qi Huang Qin Luo Xiaofeng Wei Xue wang Maozhong Li Cheng Gong fang Huang College of Public Health Capital Medical UniversityBeijing 100069China Center for Disease Prevention and Control Beijing Academy for Preventive MedicineBeijing Institute of Tuberculosis Control Research and PreventionBeijing 100013China National Institute for Viral Disease Control and Prevention China CDCBeijing 100032China

Objective To comprehensively examine the molecular epidemiological characteristics of human rhinovirus(HRV)in *** A total of 7,151 children and adults with acute respiratory tract infections(ARTIs)were recruited from 35 sentinel hospitals in Beijing between 2018 and *** respiratory samples were obtained,and epidemiological and clinical data were *** acid testing for 11 respiratory pathogens,including HRV,was performed on the *** sequenced VP4/VP2 or 5’UTR of HRV isolates to identify their genotypes using phylogenetic *** HRV was detected in 462(6.5%)cases.A total of 105 HRV genotypes were successfully identified in 359(77.7%)specimens,comprising 247(68.8%)with HRV-A,42(11.7%)with HRV-B,and 70(19.5%)with *** predominant genotype was *** was prevalent year-round with two weak peaks in spring and *** detection declined gradually between 2018 and 2022,with seven genotypes disappearing and five genotypes *** detection rate decreased by age without resurge among old ***-C was more common among children aged less than 5 years with severe community-acquired pneumonia compared to HRV-A and *** infected with HRV-B had higher rates of hospitalization,intensive care unit admission,and complications than those infected with HRV-A and *** HRV epidemics in Beijing were highly dispersed in genotypes,which probably resulted in a high prevalence of HRV infection,attenuated its seasonality,and made it more difficult to establish effective population immunity.

关键词： Human rhinovirus Genotype Epidemical characteristics Respiratory infection Community-acquired pneumonia

Nitrogen and Phosphorus Dual-Doped Multilayer Graphene as Universal Anode for Full Carbon-Based Lithium and Potassium Ion Capacitors

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Nano-Micro Letters 2019年第2期11卷 166-178页

作者： Yuting Luan Rong Hu Yongzheng fang Kai Zhu Kui Cheng Jun Yan Ke Ye Guiling wang Dianxue Cao Key Laboratory of superlight Material and surface Technology of Ministry of Education College of Material Science and Chemical EngineeringHarbin Engineering University

Lithium/potassium ion capacitors(LICs/PICs) have been proposed to bridge the performance gap between high-energy batteries and high-power ***,their development is hindered by the choice,electrochemical performance,and preparation technique of the battery-type anode ***,a nitrogen and phosphorus dual-doped multilayer graphene(NPG) material is designed and synthesized through an arc discharge process,using low-cost graphite and solid nitrogen and phosphorus *** employed as the anode material,NPG exhibits high capacity,remarkable rate capability,and stable cycling performance in both lithium and potassium ion *** excellent electrochemical performance is ascribed to the synergistic effect of nitrogen and phosphorus doping,which enhances the electrochemical conductivity,provides a higher number of ion storage sites,and leads to increased interlayer *** carbon-based NPG‖LiPF6‖active carbon(AC) LICs and NPG‖KPF6‖AC PICs are assembled and show excellent electrochemical performance,with competitive energy and power *** work provides a route for the large-scale production of dual-doped graphene as a universal anode material for high-performance alkali ion batteries and capacitors.

关键词： Arc discharge Graphene Heteroatom doping Lithium/potassium ion battery Lithium/potassium ion capacitor

Experimental study of photooxidation products of ethylbenzene

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Journal of Environmental Sciences 2010年第10期22卷 1570-1575页

作者： Mingqiang Huang Weijun Zhang Liqing Hao Zhenya wang Li fang Ruihong Kong Xiaobin Shan Fuyi Liu Liusi Sheng Key Laboratory of Atmospheric Composition and Optical Radiation Anhui Institute of Optics & Fine Mechanics Chinese Academy of Sciences Hefei 230031 China. Laboratory of Environment Spectroscopy Anhui Institute of Optics & Fine Mechanics Chinese Academy of Sciences Hefei 230031 China Department of Environmentul Science and Engineering Xiamen University Tan Kah Kee College Zhangzhou 363105 China National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

Smog chamber experiments were performed to investigate the composition of products formed from photooxidation of aromatic hydrocarbon ethylbenzene. Vacuum ultraviolet photoionization mass spectrometer and aerosol time-of-flight mass spectrometer were used to measure the products in the gas and particle phases in real-time. Experimental results demonstrated that ethylphenol, methylglyoxal, phenol, benzaldehyde, and 2-ethylfurane were the predominant photooxidation products in both the gas and particle phases. However, there were some differences between detected gas phase products and those of particle phase, for example, 2-ethylfurane, ethylglyoxylic acid, nitroethylbenzene, 3,4-dioxopentanal and ethyl-nitrophenol were only existing in the particle-phase. The possible reaction mechanisms leading to these products were also discussed and proposed.

关键词： ethylbenzne secondary organic aerosol smog chamber desorption/ionization reaction mechanism

Detection of abnormal hydroponic lettuce leaves based on image processing and machine learning

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Information Processing in Agriculture 2023年第1期10卷 1-10页

作者： Ruizhe Yang Zhenchao Wu Wentai fang Hongliang Zhang Wenqi wang Longsheng Fu Yaqoob Majeed Rui Li Yongjie Cui College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Xi’an Agriculture Machinery Management and Extension Station Xi’anShaanxi 710065China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYanglingShaanxi 712100China Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service YanglingShaanxi 712100China Faculty of Agricultural Engineering and Technology University of AgricultureFaisalabad 38000Pakistan Center for Precision and Automated Agricultural Systems Washington State UniversityProsserWA 99350USA suide County Lanhuahua Ecological Food Co. Ltd.SuideShaanxi 718000China

Accurate and fast detection of abnormal hydroponic lettuce leaves is primary technology for robotic *** and rotten leaves are main types of abnormal leaves in hydroponic *** study aims to demonstrate a feasibility of detecting yellow and rotten leaves of hydroponic lettuce by machine learning models,*** Linear Regression(MLR),K-Nearest Neighbor(KNN),and support Vector Machine(SVM).One-way analysis of variance was applied to reduce RGB,HSV,and L*a*b*features number of hydroponic lettuce *** binarization,image mask,and image filling methods were employed to segment hydroponic lettuce from an image for models *** showed that G,H,and a*were selected from RGB,HSV,and L*a*b*for training *** took about 20.25 s to detect an image with 30244032 pixels by KNN,which was much longer than MLR(0.61 s)and SVM(1.98 s).MLR got detection accuracies of 89.48%and 99.29%for yellow and rotten leaves,respectively,while SVM reached 98.33%and 97.91%,*** was more robust than MLR in detecting yellow and rotten leaves of ***,it was possible for abnormal hydroponic lettuce leaves detection by machine learning methods.

关键词： Hydroponic lettuce Machine learning Image processing Abnormal leaves Automatic sorting

Influences of increasing gate stem height on DC and RF performances of InAlAs/InGaAs InP-based HEMTs

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Chinese Physics B 2021年第1期30卷 586-592页

作者： Zhi-Hang Tong Peng Ding Yong-Bo su Da-Hai wang Zhi Jin High-Frequency High-Voltage Device and Integrated Circuits Center Institute of MicroelectronicsChinese Academy of SciencesBeijing 100029China University of Chinese Academic of Sciences Beijing 100049China

The T-gate stem height of In Al As/In Ga As In P-based high electron mobility transistor(HEMT) is increased from165 nm to 250 nm. The influences of increasing the gate stem height on the direct current(DC) and radio frequency(RF)performances of device are investigated. A 120-nm-long gate, 250-nm-high gate stem device exhibits a higher threshold voltage(Vth) of 60 m V than a 120-nm-long gate devices with a short gate stem, caused by more Pt distributions on the gate foot edges of the high Ti/Pt/Au gate. The Pt distribution in Schottky contact metal is found to increase with the gate stem height or the gate length increasing, and thus enhancing the Schottky barrier height and expanding the gate length,which can be due to the increased internal tensile stress of Pt. The more Pt distributions for the high gate stem device also lead to more obvious Pt sinking, which reduces the distance between the gate and the In Ga As channel so that the transconductance(gm) of the high gate stem device is 70 m S/mm larger than that of the short stem device. As for the RF performances,the gate extrinsic parasitic capacitance decreases and the intrinsic transconductance increases after the gate stem height has been increased, so the RF performances of device are obviously improved. The high gate stem device yields a maximum ft of 270 GHz and fmax of 460 GHz, while the short gate stem device has a maximum ft of 240 GHz and the fmax of 370 GHz.

关键词： InP-based HEMT gate stem height Pt/Ti Schottky contact gate parasitic capacitances

Study on electronic blocking layer of 403 nm Ga N-based vertical cavity surface emitting lasers

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Optoelectronics Letters 2019年第6期15卷 411-414页

作者： CUI Bi-feng wang Yang fang Tian-xiao HAO Shuai CHENG Jin LI Cai-fang Key Laboratory of Opto-Electronics Technology Ministry of Education Faculty of Information TechnologyBeijing University of Technology

In order to obtain good optical characteristics in the Ga N-based vertical-cavity surface-emitting laser(VCSEL), different kinds of Al Ga N electron blocking layers(EBL) were introduced. These were inserted coherently near the active region to limit electron leakage into the p-doped side. The research was conducted by photonic integrated circuit simulator in three-dimensional(PICS3D). The simulated results reveal that an EBL can improve the optical characteristics of a VCSEL effectively. All the advantages are due to a reduction in the electron leakage in the quantum wells. While the voltage of the five-layer EBLs LD is lower than the voltage of the seven-layer EBLs LD, the output power of the two is approximately the same, so the five-layer EBLs is the best choice for comprehensive structure analysis as the epitaxial structure can be grown more easily on it.

关键词： cavity layer surface

Bus Scheduling Using a Skip-Stop Strategy Based on Stop Relevance

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Wuhan University Journal of Natural Sciences 2020年第5期25卷 469-476页

作者： GUO Cong wang Xiaolin su Wenheng suN Feng GUO Zonghe HU Zhenda College of Urban Planning and Architecture Beijing University of TechnologyBeijing 100124China College of Transportation and Vehicle Engineering Shandong University of TechnologyZibo 255000ShandongChina Jiangsu Urban Transport Planning&Design Institute Nanjing 210000JiangsuChina School of Information Management and Engineering Shanghai University of Finance and EconomicsShanghai 200433China

This research aims to propose an efficient and economic operation mode for bus scheduling optimization by combining with the skip-stop buses and all-stop *** skip-stop tactics in bus operation provide service of high efficiency,good punctuality and high speed for long distance commuters,which attracts wide scholarly *** paper establishes a model to quantitatively evaluate the relevance between stops,and then develops a new optimization method of skip-stop tactics using the data sets of IC card and bus GPS trajectory.A collaborating scheduling optimization model considering the support and confidence among the stops is proposed to precisely suit passengers’demands and improve bus *** optimization objective is to reduce the passengers’total travel time,the number of vehicles in use,and operation energy for both the user’s and the operator’s *** methodology is developed for a single-directional route using a multi-decision choice model with genetic algorithm applied to attain efficient solutions.A case study of Qingdao,which is assessed in this new model,shows a reduction of 18.31%in total passenger travel time and 17.65%in the operational inputs as compared with solutions that do not consider the skip-stop tactics.

关键词： bus IC card data stop relevance skip-stop operation bus scheduling

Contrasting strategies of optimizing carrier concentration in bulk InSe for enhanced thermoelectric performance

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Rare Metals 2024年第9期43卷 4425-4432页

作者： Hao-Nan Shi Shu-Lin Bai Yu-Ping wang Li-Zhong su Qian Cao Cheng Chang Li-Dong Zhao School of Materials Science and Engineering Beihang UniversityBeijing 100191China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Huabei Cooling Device Co.Ltd. Hebei 065400China

Indium selenide(InSe),as a wide-bandgap semiconductor,has received extensive attention in the flexible electronics field in recent years due to its exceptional plasticity and promising thermoelectric ***,the low carrier concentration severely limits its thermoelectric performance *** this work,we conducted contrasting strategies that can be employed to increase the carrier concentration of InSe,including bandgap narrowing and heterovalent ***,the carrier concentration initially increases as a result of the reduced bandgap upon Te alloying and then slightly decreases due to the weak electronegativity of *** Br doping realizes high carrier concentration by pushing the Fermi level into the conduction bands and activating the multiple *** the other hand,both Te and Br obviously suppress the thermal conductivity due to the point defect *** contrast,Br doping realizes a higher thermoelectric performance with a maximum ZT of~0.13 at 773 K benefiting from the better optimization of carrier *** work elucidates the strategies for enhancing carrier concentration at anion sites and demonstrates the high efficiency of halogen doping in ***,the carrier concentration of InSe is promising to be further optimized,and future work should focus on employing approaches such as cation doping or secondphase compositing.

关键词： Thermoelectric InSe Carrier concentration Bandgap Heterovalent doping

Application of nonlinear color matching model to four-color ink-jet printing

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Journal of Harbin Institute of Technology(New Series) 2002年第3期9卷 270-275页

作者： su Xiaohong(苏小红) ZHANG Tianwen(张田文) GUO Maozu(郭茂祖) wang Yadong(王亚东) School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China

Through discussing the color matching technology and its application in printing industry the conventional approaches commonly used in color matching, and the difficulties in color matching, a nonlinear color matching model based on two step learning is established by finding a linear model by learning pure color data first and then a nonlinear modification model by learning mixed color data. Nonlinear multiple regression is used to fit the parameters of the modification model. Nonlinear modification function is discovered by BACON system by learning mixture data. Experiment results indicate that nonlinear color conversion by two step learning can further improve the accuracy when it is used for straightforward conversion from RGB to CMYK. An improved separation model based on GCR concept is proposed to solve the problem of gray balance and it can be used for three to four color conversion as well. The method proposed has better learning ability and faster printing speed than other historical approaches when it is applied to four color ink jet printing.

关键词： Color-matching nonlinear multiple regression fuzzy incidence cluster four-color ink-jet printing.