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Investigation of factors affecting vertical sag of stretched wire

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Nuclear Science and Techniques 2021年第2期32卷 90-100页

作者： Jian-Dong Yuan Jun-Xia Wu Bin Zhang Yuan He Jun-Hui Zhang Wen-Jun Chen Shao-Ming Wang guo-zhen sun Xu-Dong Zhang Li-Song Yan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

To study vertical sag requirements and factors affecting the stretched wire alignment method,the vertical sag equation is first derived ***,the influencing factors(such as the hanging weight or tension,span length,temperature change,elastic deformation,and the Earth’s rotation)of the vertical sag are summarized,and their validity is verified through actual ***,the essential factors affecting vertical sag,i.e.,the specific strength and length,are *** is believed that the vertical sag of a stretched wire is proportional to the square of the length and inversely proportional to the specific strength of the material.

关键词： Stretched wire Alignment Vertical sag Catenary Hyperbolic cosine Linear density Earth rotation

Fabrication and cold test of prototype of spatially periodic radio frequency quadrupole focusing linac

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Nuclear Science and Techniques 2021年第1期32卷 66-74页

作者： Pei-Yan Yu Bin Zhang Feng-Feng Wang Chen-Xing Li guo-zhen sun Zhi-Jun Wang Lu-Bei Liu Chen-Zhang Yuan Yuan He Hu-Shan Xu Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

A 325 MHz aluminum prototype of a spatially periodic RF quadrupole focusing linac was developed at the Institute of Modern Physics,Chinese Academy of Sciences,as a promising candidate for the front end of a high-current *** consists of an alternating series of crossbar H-type drift tubes and RF quadrupole *** to its special geometry,cavity fabrication is a major hurdle for its engineering development and *** this paper,we report the detailed mechanical design of this structure and describe its fabrication process,including machining,assembly,and *** field distribution was measured by the bead-pull *** results show that the field errors of both the accelerating and focusing fields are within an acceptable range.A tuning scheme for this new structure is proposed and *** cold test process and results are presented in *** development of this prototype provides valuable guidance for the application of the spatially periodic RF quadrupole structure.

关键词： Spatially periodic RF quadrupole focusing linac Mechanical structure design Bead-pull measurement

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma Yang Qu Jiaxin Ren Yingying sun zhen-Ni guo Yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

Comparison of the closed analytical solution on the parameters of the alignment and surveying of the elements of accelerator under random errors

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Radiation Detection Technology and Methods 2023年第2期7卷 234-247页

作者： Jian-Dong Yuan Jun-Xia Wu Feng-Feng Wang Wen-Jun Chen guo-zhen sun Shao-Ming Wang Xu-Dong Zhang Xiao-Dong Zhang Zhi-Jun Wang Bin Zhang Yuan He&Jun-Hui Zhang Institute of Modern Physics Chinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

Purpose Compared with the iterative approximation solution,the analytically rigorous solution of the parameters of the accelerator alignment and surveying is the closed theoretical *** make the calculated error meet the negligible principle,in this paper,such examples of the zero,small angle and small translation,only large translation and no angle,only large angle without translation and large translation and large angle parameters under random errors are *** Furthermore,Singular Value Decomposition,Eigen Value Decomposition,Polar Decomposition,Orthogonal Procrustes Analysis,and Successive Equivalent Differences Transformation are *** In all the above examples,the mutual calculation deviation of Singular Value Decomposition,Eigen Value Decomposition,Polar Decomposition,and Orthogonal Procrustes analysis methods is less than 10 *** calculation accuracy is the highest,and Successive Equivalent Differences Transformation-3 has the largest calculation error,and Successive Equivalent Differences Transformation-N is in the *** results show that the coordinate residuals,parameters offsets and point position errors of the above solutions with random errors are all nearly *** It shows that the closed analytical solution is a rigorous ***,it also shows that the constructed method of the coordinate point pairs is correct.

关键词： Accelerator Alignment Surveying Closed analytical solution

Fistulectomy as a surgical option for pulmonary arteriovenous nalformation

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Chinese Medical Journal 2009年第19期122卷 2321-2324页

作者： ZHANG Shao-yan ZHANG Zhi-tai OU Song-lei HU Yan-sheng SONG Fei-qiang LI Xin MA Xu-chen MA Xin-xin LIANG Lin LI Dong guo Lin sun zhen Department of Thoracic Surgery Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background Surgical resection remains the treatment of choice for pulmonary arteriovenous malformation but removes some normal lung parenchyma. This study aimed to evaluate the effect and safety of the lung-saving procedure of fistulectomy as an alternative to lung resection. Methods From July 2003 to July 2008, 6 selected patients with pulmonary arteriovenous malformations underwent fistulectomies. Among them, 1 patient underwent emergency operation and 2 underwent bilateral operations. One patient received postoperative embolotherapy. Results No hospital deaths or postoperative morbidity occurred. PaO2 increased significantly after operation. All patients were free of symptoms and hypoxia during a follow-up for 9 months to 5 years. Conclusions Fistulectomy is a safe and effective procedure for patients with pulmonary arteriovenous malformation and may be an alternative to lung resection.

关键词： fistula benign or congenital lesions, lung pulmonary arteries

Surface embedded binary Co-Cu hydroxy phosphate over surface of oxy/hydroxides for efficient nitrate reduction to ammonia

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Nano Research 2025年第1期18卷 195-207页

作者： Chun Zhu Yifei Yang Yike Jing zhen Zeng Xuesong Yi Wei sun Fei Yang Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Environmental Science and EngineeringHainan UniversityHaikou 570228China

Electrochemical nitrate reduction reaction(NO3RR)to ammonia is a promising approach to address excess Ncontamination in aqueous environment but suffers from a limited ammonia yield and selectivity due to the low concentration and sluggish *** work reports a three-dimensional porous electrode with binary Co_(2)Cu_(1)hydroxy phosphate embedded into the surface of Ni_(3)Co_(1)oxy/hydroxides(CoCu-PH@NiCo/Ni,“PH”means phosphate-hydroxide),which delivers a yield of 4.13 mg·h^(-1)·cm^(-2)with a high Faraday efficiency of 92.6%under a low nitrate concentration of 40 mM and provide an impressive *** embedded structure of the as-prepared catalyst exhibits unique metal coordination ligands and valence states different from the unitary *** electrochemical in situ infrared spectra and theoretical calculations revealed that the Co sites with the ability to dissociate water molecular to form adsorbed OH*can effectively provide the required protons for the deoxygenation and hydrogenation steps during NO3-conversion,thereby,effectively reducing the energy barrier of the key transition states in the NO3RR process to improve the intrinsic *** demonstrate that the rational design of binary components with the appropriate ability to activate water molecules as well as the threedimensional porous skeletal structure are expected to promote effectively the low-concentration nitrates conversion to ammonia.

关键词： nitrate reduction hydroxy phosphate surface embedded water dissociation active hydroxy adsorbed

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy Chemistry 2025年第1期100卷 710-720页

作者： Wenxuan Chen Xiu-Qing Qiao guo Hui Bojing sun Dongfang Hou Meidi Wang Xueqian Wu Tao Wu Dong-Sheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory College of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo2C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-CdS （c-CdS） and hexagonal-CdS （h-CdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge ***,the photothermal effect of Mo2C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Heterojunctions LSPR Photocatalyst Phase junction Schottky junction Photothermal effect

The value of real-time three-dimensional echocardiography in the assessment of pre-and post-operative left ventricular function in children with conotruncal defects

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The value of real-time three-dimensional echocardiography in...

The value of real-time three-dimensional echocardiography in the assessment of pre-and post-operative left ventricular function in children with conotruncal defects

第二届长三角超声医学论坛暨2009年浙江省超声医学学术年会

作者： Department of Pediatric Cardiology,Shanghai Children Medical Center Medical College of Shanghai Jiaotong University,Shanghai 200127,China guo-zhen CHEN Kun sun Mei-rong HUANG Yu-qi ZHANG

Objective This study is aimed to evaluate the value of real-time three-dimensional echocardiography (RT-3DE) in the assessment of pre-and post-operative left ventricular function in children with conotruncal defects(C...

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The value of real-time three-dimensional echocardiography in...