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A Reverse-Design Strategy for the Track Error of the Qi Tai Telescope Based on Pointing Accuracy

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Engineering 2022年第6期8卷 209-216页

作者： Na li Baoyan Duan Xiangyang Li Bin Zheng Jiang Wu Key Laboratory of Electronic Equipment Structure Design Ministry of EducationXidian UniversityXi’an 710061China

The Qi Tai Telescope(QTT),which has a 110 m aperture,is planned to be the largest scale steerable tele-scope in the world.Ideally,the telescope’s repeated pointing accuracy error should be less than 2.5 arc seconds(arcsec);thus,the telescope structure must satisfy ultra-high precision requirements.In this pur-suit,the present research envisages a reverse-design method for the track surface to reduce the difficulty of the telescope’s design and manufacture.First,the distribution characteristics of the test data for the track error were verified using the skewness coefficient and kurtosis coefficient methods.According to the distribution characteristics,the azimuth track error was simulated by a two-scale model.The error of the long period and short amplitude was characterized as large-scale and described by a trigonometric function,while the short period and high amplitude error was characterized as small-scale and simulated by a fractal function.Based on the two-scale model,effect of the error on the pointing accuracy was deduced.Subsequently,the relationship between the root mean square(RMS)of the track error and the RMS of the pointing accuracy error of the telescope was deduced.Finally,the allowable RMS value of the track error was derived from the allowable pointing accuracy errors.To validate the effectiveness of the new design method,two typical radio telescopes(the Green Bank Telescope(GBT)and the Large Millimeter Telescope(LMT))were selected as experimental examples.Through comparison,the theoretical calculated values of the pointing accuracy of the telescope were consistent with the measured values,with a maximum error of less than 10%.

关键词： Reverse design Track error Large radio telescope Two-scale model Pointing accuracy

Malnutrition associated with readmission in elderly patients with chronic obstructive pulmonary disease

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Chinese Medical Journal 2023年第3期136卷 357-359页

作者： Ting Zhao Jiayan Chen Xiangyang Li Yinggang Zhu Department of Pulmonary and Critical Care Medicine Huadong HospitalFudan UniversityShanghai 200040China

To the Editor:Compared with non-readmission chronic obstructive pulmonary disease(COPD)patients,the mortality rate of readmission patients is significantly higher(2.3%vs.13.4%),[1]which undoubtedly causes socio-economic pressures on rehabilitation care and medical resources.The potential factors affecting the risk of readmission are required to be identified.The incidence of malnutrition,occurring frequently in elderly COPD patients,varies from 20%to 45%depending on the screening tools used.As a practical,economical and effective scoring system,the Mini Nutrition Assessment(MNA)is of great value to assessing nutritional status in the elderly.Malnutrition is a state of vulnerability in elder populations and is associated with a poor long-term prognosis.This study aimed to research the impact of nutritional status related risk factors on readmission and assess the value of MNA scoring system and updated sarcopenia diagnostic criteria in predicting readmission risk for elderly COPD patients.

关键词： patients mortality admission

APPliCATION AND DEVELOPMENT OF ‘GREEN’ PREVENTIVE AND CONTROL TECHNOLOGIES IN GUIZHOU TEA PLANTATIONS

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Frontiers of Agricultural Science and Engineering 2022年第1期9卷 75-81页

作者： Xiangyang Li linhong JIN Zhuo CHEN Baoan SONG State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China

The application and development of ‘green’ preventive technologies in teaplantations is an important means of ensuring tea quality and ecologicalsafety. Ecological, agronomic and biological controls are the main preventivemeasures used in Guizhou Province. This paper summarizes the ‘green’preventive technologies being applied in Guizhou tea plantations, including theuse of plant defense inducers to regulate tea plant responses to pathogens,natural enemies to control pest species causing damage to shoots andTrifolium repens to control the main weed species. In addition, it summarizesthe integrated ‘green’ preventive technologies being used in Guizhou andprovides a foundation for the ecological maintenance of tea plantations.

关键词： ‘green’prevention natural enemies plant defense inducers tea plantations Trifolium repens

Fast charge transport motivated by tunable Mo2C/Mo2N high-quality heterointerface for superior pseudocapacitive storage

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能源化学:英文版 2023年第8期83卷 465-477,I0012页

作者： Yanjun Gao Shaohua Zhang lingrui Xu Xiangyang Li lijie li lixia Bao Jiong Peng Xin li School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China School of Material Science and Engineering Beijing Institute of TechnologyBeijing 100081China Analysis&Testing Center Beijing Institute of TechnologyBeijing 100081China

The development of potential transition-metal carbide/nitride heterojunctions is hindered by overall understanding and precise modulation for heterointerface effects.Herein,we demonstrate that Mo_(2)C/Mo_(2)N heterojunction with the precisely regulated high-quality interface can achieve marvelous rate performance and energy output via enlarging the interface-effect range and maximizing "accelerated charge" amount The heterointerface mechanism improving properties is synergistically revealed from kinetics and thermodynamics perspectives.Kinetics analysis confirms that the self-built electric field affords a robust force to drive rapid interface electrons/ions migration.The small adsorption energy,high density of states and quite low diffusion barrier thermodynamically enhance the electrochemical reaction dynamics on heterointerface.Consequently,the almost optimal performance of ultrahigh capacitance retention(85.6% even at 10 A g^(-1)) and pronounced energy output(96.4 Wh kg^(-1))in hybridsupercapacitors than other Mo_(2)C/Mo_(2)N-based materials is presented.This work gives new insight into the energy storage mechanism of heterojunction and guides the design of advanced electrodes.

关键词： Energy storage Hybrid supercapacitors Pseudocapacitance Heterojunction High-quality interface

The brain,another potential target organ,needs early protection from SARS-CoV-2 neuroinvasion

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Science China(life Sciences) 2020年第5期63卷 771-773页

作者： Zhengqian li Yuguang Huang xiangyang Guo Department of Anesthesiology Peking University Third HospitalBeijing 100191China Department of Anesthesiology Peking Union Medical College HospitalBeijing 100730China

With the outbreak and rapid spread of the novel coronavirus disease(COVID-19)around the world,humans are engaged in a life-and-death battle with the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),formerly... 详细信息

关键词： invasion acute respiratory

Growth and Transcriptomics Analysis ofMichelia macclurei Dandy Plantlets with Different LED Quality Treatments

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国际实验植物学杂志(英文) 2023年第10期92卷 2891-2906页

作者： Zhaoli Chen Ying liu Bingshan Zeng Qingbin Jiang Shengkun Wang Xiangyang Li Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou510520China

Michelia macclurei Dandy is a significant tree species that has extensive cultivation for forestry and horticulture purposes in southern China,owing to its economic and practical importance.light quality influences plantlet growth and development during tissue culture.However,the growth characteristic and molecular regulation of M.macclurei under different light quality conditions are not well understood yet.In this study,we investigated the morphological,chlorophyll content,and transcriptomic responses of M.macclurei plantlets under different light-emitting diode(LED)qualities,including white,blue,and red light.The results showed that blue light significantly increased plant height(21.29%)and leaf number(18.65%),while red light decreased plant height and leaf number by 7.53%and 16.49%,respectively.In addition,the plantlets’chlorophyll content and etiolation rate were significantly reduced by blue and red light quality compared to white light.Compared to white light,blue light had a negative effect,leading to decreased rooting rate(64.28%),root number(72.72%),and root length(75.86%).Conversely,red light had a positive effect,resulting in increased rooting rate(24.99%),root number(109.58%),and root length(72.72%).Transcriptome analysis identified 54 differentially expressed genes(DEGs)in three groups that consisted of blue light vs.white light(BL-vs-WL),red light vs.white light(RL-vs-WL),and red light vs.blue light(RL-vs-BL).Specifically,21,7,and 41 DEGs were identified in the three groups,respectively.The DEGs found in the RL-vs-WL and BL-vs-WL groups were involved in plant hormone signaling,nitrogen metabolism,and phenylpropanoid biosynthesis pathways,which suggests that M.macclurei plantlets adapt to the changes of light quality via modulating gene expression.Overall,our study provides valuable insights for understanding the molecular and morphological responses of M.macclurei plantlets under different light qualities.

关键词： Michelia macclurei plantlets growth characteristics transcriptome

Development Trend and Coping Strategies of Academic Journals in Daily Chemistry Area

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China Detergent & Cosmetics 2022年第3期7卷 37-42页

作者： li xiangyang China Research Institute of Daily Chemistry Co. Ltd.China

Combining with the present situation of chemistry-related academic journals,the author of this paper has summarized and analyzed the current characteristics and development trends of academic periodicals in daily chemical field.Moreover,the author has proposed the coping strategies regarding the development of future chemical academic journals,focusing mainly on the system and concept innovation concerning media convergence,fusion path optimization,refinement of user needs experience as well as the improvement of editorial staff.

关键词： daily chemistry academic journal trend strategy media convergence

Two-dimensional bipolar magnetic semiconductors with high Curie-temperature and electrically controllable spin polarization realized in exfoliated Cr(pyrazine)_(2) monolayers

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Science China Chemistry 2021年第12期64卷 2212-2217页

作者： Xiangyang Li Haifeng Lv Xiaofeng liu Tong Jin Xiaojun Wu Xingxing li Jinlong Yang Hefei National Laboratory of Physical Science at the Microscale Department of Chemical PhysicsSynergetic Innovation Center of Quantum Information&Quantum PhysicsUniversity of Science and Technology of ChinaHefei230026China Department of Chemistry Key Laboratory of Functional Inorganic Materials of Anhui ProvinceAnhui UniversityHefei230601China

Exploring two-dimensional(2D)magnetic semiconductors with room-temperature magnetic ordering and electrically controllable spin-polarization is a highly desirable but challenging task for nano-spintronics.Here,through first-principles calculations,we propose to realize such a material by exfoliating the recently synthesized organometallic layered crystal li0.7[Cr(pyz)_(2)]Cl0.7·0.25(THF)(pyz=pyrazine,THF=tetrahydrofuran).The feasibility of exfoliation is confirmed by the rather low exfoliation energy of 0.27 J m^(−2),even smaller than that of graphite.In exfoliated Cr(pyz)_(2)monolayers,each pyrazine ring grabs one electron from the Cr atom to become a radical anion,and then a strong d-p direct-exchange magnetic interaction emerges between Cr cations and pyrazine radicals,resulting in room-temperature ferrimagnetism with a Curie temperature of 342 K.Moreover,the Cr(pyz)_(2)monolayer is revealed to be an intrinsic bipolar magnetic semiconductor where electrical doping can induce half-metallic conduction with controllable spin-polarization direction.

关键词： two-dimensional material ferrimagnetism bipolar magnetic semiconductor half metal first principles

Will Pet Care Products Become a New Track for Making Money?

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China Detergent & Cosmetics 2022年第2期7卷 35-38页

作者： li xiangyang Editorial Department of Detergent&Cosmetics China

“Personified pet raising”has become a new buzzword of the pet industry.In the past,people raise pets mainly for apparent functional demands like“looking after the house”.By comparison,more and more pet-raising people are now treating pets as their own family members.Under this concept,consumption scenes of pet care are keeping on being upgraded and iterated.Apart from basic bathing shampoo,more subdivided products such as hair-care essence and oral spray have occurred.According to GIM market investigation report,the scale of the global pet care market exceeded 232.0 billion U.S.Dollars(equivalent to about RMB 1.47 trillion Yuan)in 2020,and is hoped to increase at a compound annual rate of more than 6.1%in 2021-2027.

关键词： looking own subdivided