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Preparation And Characterization of a New Blend of Poly(2-hydroxyethyl methacrylate) And Poly(ethylene glycol)

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Chinese Chemical Letters 1997年第11期8卷 953-956页

作者： Wei Bin CheN Han Qiao FENG da yong he Chao Hui YE(Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071.)(Polymer Physics Laboratory, Changchun Institute Lab. Magnetic Reson./Atom./Molec. P. Wuhan Inst. of Phys. and Mathematics Chinese Academy of Sciences Wuhan 430071 China Polymer Physics Laboratory Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

A new blend of poly(2-hydroxyethyl methacrylate) (PheMA) with poly (ethylene glycol) (PEG) was prepared. The results from solid-state NMR indicate that the PheMA/PEG(88:12, w/w) blend is miscible on a molecular level.

关键词： PheMA Preparation And Characterization of a New Blend of Poly ethylene glycol hydroxyethyl methacrylate Blend

Waveguide distribution system of the hePS linac

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Radiation Detection Technology and Methods 2023年第4期7卷 502-513页

作者： Xiang he Jing-Ru Zhang Hua Shi Ou-Zheng Xiao Jing-Dong Liu Nan Gan Hao Zeng Xiao-Ping Li Guan Shu Feng-Li Zhao Sheng-Chang Wang Xin-Peng Ma Cai Meng da-yong he Fei Li Dong Dong Zu-Sheng Zhou Jing-Yi Li Jian-Li Wang Bing-Lin Deng Pi-Long Tian Xu-Jian Wang Hong Song Qi Yang Xiang-Cheng Kong National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Zhang Jiang Laboratory Shanghai200120China

Purpose The High-Energy Photon Source(hePS)is a 6 GeV storage ring-based light source under construction in Beijing,China.Its accelerator consists of a 6 GeV storage ring,a full-energy booster,an S-band normal-conducting 500 MeV linac,and three transport lines.As the beginning of hePS,a stable linac is quite important,which needs a qualified waveguide distribution system to transmit microwave power from klystrons to accelerating structures.Methods Installation and high-power conditioning of the hePS linac were performed from February to September 2022.The assembly and conditioning of the waveguide distribution system were completed in April and July,respectively.The design of the waveguide distribution system began in 2018 and was finalized at the end of 2020 after multiple iterations.Results Owing to careful design,fabrication,and assembly preparation,the assembly and conditioning of the system proceeded smoothly and considerable time was saved.Conclusion The entire process from the design to the ultimate realization of the system is introduced in detail in this paper.Satisfactory measurement results were obtained for some waveguide components.

关键词： hePS linac Waveguide distribution system System design Assembly and commissioning High-power conditioning

System design and measurements of flux concentrator and its solid-state modulator for CEPC positron source

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Nuclear Science and Techniques 2021年第7期32卷 108-117页

作者： Jing-Dong Liu Xiao-Ping Li Cai Meng Yun-Long Chi Guo-Xi Pei da-yong he Jing-Yi Li Xian-Jing Sun Jing-Ru Zhang Lei Shang Jian-Bin Zhu National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Positron sources are one of the most important components of the injector of a circular electron positron collector(CEPC).The CEPC is designed as an e^(+)e^(−)collider for a Higgs factory.Its accelerator system is composed of 100-km-long storage rings and an injector.The design goal of the positron source is to obtain positron beams with a bunch charge of 3 nC.The flux concentrator(FC)is one of the cores of the positron source.This paper reports the design,development,and measurements of an FC prototype system.The prototype includes an FC and an all-solid-state high-current pulse modulator.Preliminary tests show that the peak current on the FC can reach 15.5 kA,and the peak magnetic field can reach 6.2 T.The test results are consistent with the theoretical simulation.The FC system fulfills the requirements of the CEPC positron source as well as provides a reference for the development of similar devices both domestically and abroad.

关键词： CEPC positron source Flux concentrator Solid-state modulator High current Peak magnetic field

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

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Current Medical Science 2024年第3期44卷 463-474页

作者： Rui he yong CheN Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(T2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body metabolism.Exosomes are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(AT Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms.However,the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated.In this review,we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders.Moreover,we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

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Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan he Weidong Wang Zhi Ding Wen he yong he Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle gyroscopes.However,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly processing.here,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating gyroscope.We remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional micromachining.By utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS technology.In addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical resonators.This work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial navigation.Moreover,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

On n-universal quadratic forms over dyadic local fields

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Science China Mathematics 2024年第7期67卷 1481-1506页

作者： Zilong he yong Hu School of Computer Science and Technology Dongguan University of TechnologyDongguan523808China Department of Mathematics Southern University of Science and TechnologyShenzhen518055China

Let n≥2 be an integer. We give necessary and sufficient conditions for an integral quadratic form over dyadic local fields to be n-universal by using invariants from Beli's theory of bases of norm generators.Also, we provide a minimal set for testing n-universal quadratic forms over dyadic local fields, as an analogue of Bhargava and Hanke's 290-theorem(or Conway and Schneeberger's 15-theorem) on universal quadratic forms with integer coefficients.

关键词： integral quadratic forms n-universal quadratic forms dyadic fields 290-theorem

Anoctamin 4 defines glucose-inhibited neurons in the ventromedial hypothalamus

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Neural Regeneration Research 2024年第6期19卷 1177-1178页

作者： Longlong Tu Yanlin he yong Xu Children's Nutrition Research Center Department of Pediatrics Baylor College of Medicine Department of Molecular and Cellular Biology Section of Endocrinology Diabetes and Metabolism Department of Medicine Baylor College of Medicine Brain Glycemic and Metabolism Control Department Pennington Biomedical Research Center Louisiana State University

Glucose is the primary fuel source of the brain,and therefore glucose levels need to be tightly regulated and maintained within a small physiological range.Certainly,the body necessitates a stable supply of energy mainly provided by glucose for various bodily functions.High or low blood glucose levels would impair the physiological functions of various organs of the body.Prolonged high blood glucose(i.e.,

关键词： HYPOGLYCEMIA

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

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Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling Si Hongli Li david da yong Chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan Zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment steps.An effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of PFCs.Conditions affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were studied.The optimum conditions were found to be 120℃,10 min,and 3 cycles,respectively.LC-MS/MS method was developed to obtain the optimal sensitivity specific to PFCs.The method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/g.To ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent contamination.The optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target compounds.Finally,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to 2019.It is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

Subnatural-linewidth fluorescent single photons

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Photonics Research 2024年第4期12卷 625-637页

作者： he-BIN ZHANG GAO-XIANG LI yong-CHUN LIU State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Department of Physics Huazhong Normal UniversityWuhan 430079China Frontier Science Center for Quantum Information Beijing 100084China

Subnatural-linewidth single photons are of vital importance in quantum optics and quantum information science.According to previous research, it appears difficult to utilize resonance fluorescence to generate single photons with subnatural linewidth. here we propose a universally applicable approach to generate fluorescent single photons with subnatural linewidth, which can be implemented based on Λ-shape and similar energy structures.Further, the general condition to obtain fluorescent single photons with subnatural linewidth is revealed.The single-photon linewidth can be easily manipulated over a broad range by external fields, which can be several orders of magnitude smaller than the natural linewidth. Our study can be easily implemented in various physical platforms with current experimental techniques and will significantly facilitate the research on the quantum nature of resonance fluorescence and the technologies in quantum information science.

关键词： quantum utilize optics