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Design and test of the key components for a combing-type tobacco harvester

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 145-153页

作者： Chaoran sun shaohui Tan Songling sun Mingtao Xiao Limei Chen Wenke Ai Zhihua Qiu Ping Jiang Yang He School of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China Truking Technology Limited Ningxiang 410600HunanChina Construction of tobacco leaf production infrastructure of Hunan Province Company of China National Tobacco Corporation office Changsha 410009China

In response to the problems of low efficiency,high labor intensity,and low mechanization in manual tobacco harvesting,a comb-off tobacco picking device for southern hilly tobacco areas was designed following the agronomic requirements and the principle of manual picking of tobacco harvesting in southern China.The device was composed of the power chassis,picking mechanism,and storage mechanism.This study involved the theoretical analysis,structural design,and modeling of the key components,such as chassis structure,combing-type picking mechanism,and power synchronization mechanism.The results of the motion analysis and calculation of the picking process demonstrated that the adjustment range of the comb chain elevation angles was from 12.4°to 20.9°,the comb rod installation distance was 76.2 mm,and the synchronizing mechanism transmission ratio was 3:10.One-factor test and three-factor three-level orthogonal test was performed with the forward speed of the chassis,the distance between the picking device baffles and the elevation angle of the chain with the combing bar as test factors,and the rate of broken and missed tobacco picking as evaluation indicators.It was revealed that the optimal combination of the forward speed of the chassis,the distance between the baffles,and the chain elevation angle were 1.5 km/h,75 mm,and 12.4°,respectively.Moreover,verification tests suggested that the breakage rate of tobacco leaves was 9.99%,and the probability of missed tobacco picking was 7.31%,both of which satisfy the agriculture requirements and the operational requirements in the agricultural machinery certification syllabus.

关键词： harvesting machinery leaf tobacco combing-type tiered harvest synchronizing mechanism

Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators

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Nano-Micro Letters 2024年第3期16卷 149-168页

作者： Chenyang Xing Zihao Li Ziao Wang shaohui Zhang Zhongjian Xie Xi Zhu Zhengchun Peng State Key Laboratory of Radio FrequencyHeterogeneous Integration Shenzhen UniversityShenzhen 518060People’s Republic of China Center for Stretchable Electronics and NanoSensors College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhen 518172People’s Republic of China Institute of Pediatrics Shenzhen Children’s HospitalShenzhen 518038GuangdongPeople’s Republic of China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060People’s Republic of China

The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns.However,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface structures.Herein,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic liquid.Anions,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk Te.The resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light absorption.We also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun irradiation.Furthermore,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions.

关键词： Tellurium High entropy Electrochemical modification Solar absorption Evaporation rate

Coxsackievirus B3 HFMD animal models in Syrian hamster and rhesus monkey

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Virologica Sinica 2024年第2期39卷 290-300页

作者： Suqin Duan Wei Zhang Yongjie Li Yanyan Li Yuan Zhao Weihua Jin Quan Liu Mingxue Li Wenting sun Lixiong Chen Hongjie Xu Jie Tang Jinghan Hou Zijun Deng Fengmei Yang shaohui Ma Zhanlong He Institute of Medical Biology Chinese Academy of Medical Sciences Medical Primate Research Center Peking Union Medical CollegeYunnan Key Laboratory of Vaccine Research Development on Severe Infectious DiseaseKunming650118China

Coxsackievirus B3(CVB3)is the pathogen causing hand,foot and mouth disease(HFMD),which manifests across a spectrum of clinical severity from mild to severe.However,CVB3-infected mouse models mainly demonstrate viral myocarditis and pancreatitis,failing to replicate human HFMD symptoms.Although several enteroviruses have been evaluated in Syrian hamsters and rhesus monkeys,there is no comprehensive data on CVB3.In this study,we have first tested the susceptibility of Syrian hamsters to CVB3 infection via different routes.The results showed that Syrian hamsters were successfully infected with CVB3 by intraperitoneal injection or nasal drip,leading to nasopharyngeal colonization,acute severe pathological injury,and typical HFMD symptoms.Notably,the nasal drip group exhibited a longer viral excretion cycle and more severe pathological damage.In the subsequent study,rhesus monkeys infected with CVB3 through nasal drips also presented signs of HFMD symptoms,viral excretion,serum antibody conversion,viral nucleic acids and antigens,and the specific organ damages,particularly in the heart.Surprisingly,there were no significant differences in myocardial enzyme levels,and the clinical symptoms resembled those often associated with common,mild infections.In summary,the study successfully developed severe Syrian hamsters and mild rhesus monkey models for CVB3-induced HFMD.These models could serve as a basis for understanding the disease pathogenesis,conducting pre-trial prevention and evaluation,and implementing post-exposure intervention.

关键词： Coxsackievirus B3(CVB3) Hand foot and mouth disease(HFMD) Animal models Syrian hamster Rhesus monkey

Challenges and opportunities in 2D high-entropy alloy electrocatalysts for sustainable energy conversion

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SusMat 2023年第6期3卷 730-748页

作者： Die Lu Xinyao Fu Dong Guo Wei Ma shaohui sun Gonglei Shao Zhen Zhou Interdisciplinary Research Centerfor Sustainable Energy Scienceand Engineering(IRC4SE^(2)) School of Chemical EngineeringZhengzhou UniversityZhengzhouChina

Two-dimensional(2D)high-entropy alloys(HEAs)have emerged as promising electrocatalysts due to the benefits of polymetallic coordination and robust elec-trical conductivity.However,the multiple elements in 2D HEAs pose challenges in achieving a uniform composition and maintaining a 2D limit morphology,complicating their structural characterization.Furthermore,even minor adjust-ments to the composition can significantly alter the properties of 2D HEAs,underscoring the need for a deeper understanding of their structure-property relationships to advance synthesis and application.Therefore,this review crit-ically examines the intrinsic factors influencing synthesis methods and the practical applications of 2D HEAs in electrocatalysis for sustainable energy con-version.The urgency is emphasized for developing new synthesis techniques,enhancing advanced characterization methods,and gaining profound insights into the functional mechanisms of 2D HEAs.

关键词： electrocatalysis high-entropy alloys structure-property relationships synthesis methods two-dimensional materials

System Integration of Terrestrial Mobile Communication and Satellite Communication——The Trends, Challenges and Key Technologies in B5G and 6G

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China Communications 2020年第12期17卷 156-171页

作者： Shanzhi Chen shaohui sun Shaoli Kang State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunication TechnologyBeijing 100191China

Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.

关键词： satellite communication terrestrial mobile communication system integration B5G 6G space internet

论新质生产力对马克思主义生产力理论的守正创新

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河南社会科学 2024年第7期32卷 1-9页

作者：陈绍辉孙熙国北京大学习近平新时代中国特色社会主义思想研究院北京100871

马克思主义关于生产力的实质、要素、生产力与生产关系、生产力与人类解放等方面的论述,既科学地揭示了经济社会发展规律和人类解放道路,也为在新历史发展方位上加快发展新质生产力提供了重要遵循。习近平总书记关于新质生产力的新时代... 详细信息

马克思主义关于生产力的实质、要素、生产力与生产关系、生产力与人类解放等方面的论述,既科学地揭示了经济社会发展规律和人类解放道路,也为在新历史发展方位上加快发展新质生产力提供了重要遵循。习近平总书记关于新质生产力的新时代阐释,正当其时,意义重大:新质生产力实现了在生产力内涵上的质的跃升;重构和拓展了生产力要素结构;新质生产力本身就是绿色生产力,有利于打破经济发展与环境保护二元对立的窠臼;新质生产力坚持高水平对外开放,创新发展了马克思“世界市场”理论;在方法上提出先立后破、因地制宜发展新质生产力的实践辩证法;在全面深化改革上提出把握与新质生产力相适应的新型生产关系的“历史主动”;在思想上实现了中华民族“创新”禀赋的创造性转化。新质生产力不仅是对马克思主义生产力理论的守正创新,开辟了马克思主义政治经济学新境界,而且为在理论上摆脱西方经济学“学徒”状态、实践上打破“脱实向虚”和“脱钩断链”,提供了强大思想武器和科学行动纲领。

关键词：新质生产力政治经济学生产关系经济新动能

稀土离子La^(3+)掺杂铌酸锶钡玻璃陶瓷储能性能

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硅酸盐学报 2024年第4期52卷 1310-1319页

作者：王娇汪庆王远孙兴郝好山刘少辉河南工程学院材料工程学院郑州451191

高功率密度、高能量密度玻璃陶瓷电介质材料在小型化、轻量化、集成化脉冲功率器件领域具有重要的应用价值。通过高温熔融结合温度控制结晶工艺制备出不同La^(3+)掺杂量铌酸锶钡基玻璃陶瓷。测试结果表明:稀土离子La^(3+)掺杂可以提高... 详细信息

高功率密度、高能量密度玻璃陶瓷电介质材料在小型化、轻量化、集成化脉冲功率器件领域具有重要的应用价值。通过高温熔融结合温度控制结晶工艺制备出不同La^(3+)掺杂量铌酸锶钡基玻璃陶瓷。测试结果表明:稀土离子La^(3+)掺杂可以提高玻璃陶瓷的结晶度与钨青铜结构Ba_(0.5)Sr_(0.5)Nb_(2)O_(6)相含量,从而提高了铌酸锶钡基玻璃陶瓷的相对介电常数,La^(3+)掺杂铌酸锶钡玻璃陶瓷具有出色的温度稳定性和较低的损耗。稀土离子La^(3+)掺杂可以改善铌酸锶钡基玻璃陶瓷的微观结构同时降低玻璃陶瓷的界面激活能,从而提升玻璃陶瓷的耐击穿场强。对于La^(3+)掺杂的摩尔分数为1.0%时,玻璃陶瓷的耐击穿场强达到了1458 kV/cm,其相应的介电常数为96.3,最高的储能密度达到9.36 J/cm^(3),是未掺杂铌酸锶钡玻璃陶瓷的能量密度2.25倍。该研究对开发高储能密度玻璃陶瓷提供了一种实验思路。

关键词：铌酸锶钡玻璃陶瓷储能性能介电性能微观结构

Analysis of Non-Orthogonal Multiple Access for 5G

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China Communications 2016年第S2期13卷 52-66页

作者： Yingmin Wang Bin Ren shaohui sun Shaoli Kang Xinwei Yue School of Information and Communication Engineering Beijing University of Posts & Telecommunications State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunication Technology National Engineering Laboratory of New Generation Mobile Communication Network and Chip Technology China Academy of Telecommunication Technology School of Electronic and Information Engineering Beihang University

The major challenge faced by the fifth generation(5G) mobile network is higher spectral efficiency and massive connectivity,i.e.,the target spectrum efficiency is 3 times over 4G,and the target connection density is one million devices per square kilometer.These requirements are difficult to be satisfied with orthogonal multiple access(OMA) schemes.Non-orthogonal multiple access(NOMA) has thus been proposed as a promising candidate to address some of the challenges for 5G.In this paper,a comprehensive survey of different candidate NOMA schemes for 5G is presented,where the usage scenarios of5 G and the application requirements for NOMA are firstly discussed.A general framework of NOMA scheme is established and the features of typical NOMA schemes are analyzed and compared.We focus on the recent progress and challenge of NOMA in standardization of international telecommunication union(ITU),and 3rd generation partnership project(3GPP).In addition,prototype development and future research directions are also provided respectively.

关键词： 5G non-orthogonal multiple access NOMA SCMA PDMA MUSA MPA SIC

Loading-Balance Relay-Selective Strategy Based on Stochastic Dynamic Program

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Tsinghua Science and Technology 2018年第4期23卷 493-500页

作者： Wei Zhao Lin Zhao Weidong Wu Sigen Chen shaohui sun Yong Cao Information and Communication Branch Heilongjiang Electric Power Company (LTD) SGCC School of Mathematics Science Heilongjiang University

A Relay-Assisted （RA） network with relay selection is considered as a type of effective technology to improve the spectrum and energy efficiency of a cellular network. However, loading balance of the assisted relay node becomes an inevitable bottleneck in RA network development because users do not follow uniform distribution. Furthermore, the time-varying channel condition of wireless communication is also a major challenge for the RA network with relay selection. To solve these problems and improve the practicability of the RA network, a Loading Balance-Relay Selective （LBRS） strategy is proposed for the RA network in this paper. The proposed LBRS strategy formulates the relay selection of the RA network under imperfect channel state information assumption as a Multistage Decision （MD） problem. An optimal algorithm is also investigated to solve the proposed MD problem based on stochastic dynamic program. Numerical results show that the performance of the LBRS strategy is better than that of traditional greedy algorithm and the former is effective as an exhaustive search-based method.

关键词： relay-assisted network relay selection stochastic dynamic program