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Conceptual design of a 714-MHz RFQ for compact proton injectors and development of a new tuning algorithm on its aluminium prototype

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Nuclear Science and Techniques 2024年第1期35卷 45-58页

作者： Yi-Xing Lu Wen-cheng Fang yu-sen Guo Zhen-Tang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800China University of Chinese Academy of Sciences Beijing 101408China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204China Shanghai Key Laboratory of Cryogenics&Superconducting RF Technology Shanghai 201800China ShanghaiTech University Shanghai 201210China

Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator *** RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this *** RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary *** develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a *** aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning ***,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning *** from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.

关键词： Compact proton injector RFQ IH-DTL High gradient Tuning

Impact of citrus fruit and hesperidin intake on multiple health outcomes:An umbrella review

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Journal of Nutritional Oncology 2023年第1期8卷 16-24页

作者： yu-sen cheng Yong Zhou Division of Gastrointestinal Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengduSichuanChina

Citrus fruits are rich sources of several biologically active flavonoids such as hesperidin,naringin,and polymethoxylated *** evaluated the evidence of associations between citrus fruit or hesperidin intake and multiple health *** umbrella review was conducted for studies performed in ***,246 articles were initially identified by searching in 4 ***-two meta-analyses and systematic reviews with 28 health outcomes met the inclusion *** fruit intake had beneficial effects on all-cause mortality(relative risk[RR].0.90;95%confidence interval[95%CI],0.86 to 0.94),cardiovascular diseases(RR,0.78;95%CI,0.66 to 0.92),coronary heart disease(RR,0.91;95%CI,0.86 to 0.96),stroke(RR,0.74;95%CI,0.65 to 0.84),type 2 diabetes mellitus(RR,0.85;95%CI,0.78 to 0.92),and several ***-response analyses indicated that each 100-g/d increase in citrus fruit intake could reduce the risks of all-cause mortality by 6%(RR,0.94;95%CI,0.88 to 1.00),stroke by 22%(RR,0.78;95%CI,0.69 to 0.90),and cardia gastric cancer by 40%(RR,0.60;95%CI,0.44 to 0.83).Citrus fruit intake also had beneficial effects on the lipid profile and body weight control(weighted mean difference,−1.28;95%CI,−1.82 to−0.74).Grapefruits could reduce the systolic blood pressure(weighted mean difference,−2.43,95%CI,−4.77 to−0.09).Hesperidin supplementation significantly improved *** fruit intake was generally safe and beneficial for multiple health outcomes in ***,grapefruit and pomelo juice may affect the bioavailability of various medications,so care should be exercised before increasing the intake of these fruits or their juices.

关键词： Citrus fruit Hesperidin Health Umbrella review Meta-analysis Systematic review

Iron oxide/CNT-based artificial nacre for electromagnetic interference shielding

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Nano Research 2024年第7期17卷 6560-6566页

作者： cheng-Xin yu yu-Feng Meng Bo Yang Jun Pang Xiang-sen Meng Zi-Ye Zhao Qing-yue Wang Li-Bo Mao Zhi-Kun Wu Shu-Hong yu Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Department of Chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China

Biological structural materials,despite consisting of limited kinds of compounds,display multifunctionalities due to their complex hierarchical *** some biomimetic strategies have been applied in artificial materials to enhance their mechanical stability,the simultaneous optimization of other functions along with the mechanical properties via biomimetic designs has not been thoroughly ***,iron oxide/carbon nanotube(CNT)-based artificial nacre with both improved mechanical and electromagnetic interference(EMI)shielding performance is fabricated via the mineralization of Fe_(3)O_(4)onto a CNTincorporated *** micro-and nano-structures of the artificial nacre are similar to those of natural nacre,which in turn improves its mechanical *** alternating electromagnetic wave-reflective CNT layers and the wave-absorptive iron oxide layers can improve the multiple reflections of the waves on the surfaces of the reflection layers,which then allows sufficient interactions between the waves and the absorption ***,compared with the reflection-dependent EMI-shielding of the non-structured material,the artificial nacre exhibits strong absorption-dependent shielding behavior even with a very low content of wave-absorptive *** to the high mechanical stability,the shielding effectiveness of the artificial nacre that deeply cut by a blade is still maintained at approximately 70%−96%depending on the incident wave *** present work provides a new way for designing structural materials with concurrently enhanced mechanical and functional properties,and a path to combine structural design and intrinsic properties of specific materials via a biomimetic strategy.

关键词： artificial nacre electromagnetic interference shielding biomineralization biomimetic material hierarchical structure

A flame-retardant binder with high polysulfide affinity for safe and stable lithium–sulfur batteries

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Science China Chemistry 2024年第3期67卷 1028-1036页

作者： Guowei yu Guofeng Ye cheng Wang Chenyang Wang Zhaoyun Wang Pu Hu yu Li Xi-Xi Feng Shuang-Jie Tan Min Yan sen Xin Zhitian Liu Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Hubei Engineering Technology Research Center of Optoelectronic and New Energy MaterialsSchool of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Lithium-sulfur(Li-S) batteries have shown promises for the next-generation, high-energy electrochemical storage, yet are hindered by rapid performance decay due to the polysulfide shuttle in the cathode and safety concerns about potential thermal runaway. To address the above challenges, herein, we show a flame-retardant cathode binder that simultaneously improves the electrochemical stability and safety of batteries. The combination of soft and hard segments in the polymer framework of binders allows high flexibility and mechanical strength for adapting to the drastic volume change during the Li(de)intercalation of the S cathode. The binder contains a large number of polar groups, which show the high affinity to polysulfides so that they help to anchor active S species at the cathode. These polar groups also help to regulate and facilitate the Li-ion transport, promoting the kinetics of polysulfide conversion reaction. The binder contains abundant phosphine oxide groups, which, in the case of battery's thermal runaway, decompose and release PO· radicals to quench the combustion reactions and stop the fire. Consequently, Li-S batteries using the new cathode binder show the improved electrochemical performance, including a low-capacity decay of 0.046% per cycle for 800 cycles at 1 C and favorable rate capabilities of up to 3 C. This work offers new insights on the practical realization of high-energy rechargeable batteries with stable storage electrochemistry and high safety.

关键词： lithium–sulfur battery polymer binder polysulfide affinity flame retardancy

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Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： Hao-ran Zhou Hao Yang Huai-qian Li Ying-chun Ma sen yu Jian shi Jing-chang cheng Peng Gao Bo yu Zhi-quan Miao Yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

Microstructure recognition of steels by machine learning based on visual attention mechanism

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Journal of Iron and Steel Research(International) 2024年第4期31卷 909-923页

作者： Xing-yu Chen Lin cheng cheng-yang Hu yu-peng Zhang Kai-ming Wu The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)Metallic Composite Materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the *** representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction *** is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure *** reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

Capillary Property of Entangled Porous Metallic Wire materials and Its Application in Fluid Buffers:Theoretical Analysis and Experimental Study

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Defence Technology（防务技术） 2024年第1期31卷 400-416页

作者： yu Tang Yiwan Wu Hu cheng Rong Liu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350156China AECC Guizhou Liyang Aviation Power Co. LTDGuiyang 550014China College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350156China

Strong impact does serious harm to the military industries so it is necessary to choose reasonable cushioning material and design effective buffers to prevent the impact of *** on the capillary property entangled porous metallic wire materials(EPMWM),this paper designed a composite buffer which uses EPMWM and viscous fluid as cushioning materials under the low-speed impact of the recoil force device of weapon equipment(such as artillery,mortar,etc.).Combined with the capillary model,porosity,hydraulic diameter,maximum pore diameter and pore distribution were used to characterize the pore structure characteristics of *** calculation model of the damping force of the composite buffer was *** low-speed impact test of the composite buffer was *** parameters of the buffer under low-speed impact were identified according to the model,and the nonlinear model of damping force was *** test results show that the composite buffer with EPMWM and viscous fluid can absorb the impact energy from the recoil movement effectively,and provide a new method for the buffer design of weapon equipment(such as artillery,mortar,etc.).

关键词： Entangled porous metallic wire materials Capillary property Viscousfluid Low-speed impact Damping force

The hard X-ray nanoprobe beamline at the SSRF

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Nuclear Science and Techniques 2024年第7期35卷 79-88页

作者： Yan He Hui Jiang Dong-Xu Liang Zhi-sen Jiang Huai-Na yu Hua Wang cheng-Wen Mao Jia-Nan Xie Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China

The hard X-ray nanoprobe beamline BL13U is a phase-II beamline project at the Shanghai Synchrotron Radiation *** beamline aims to enable comprehensive experiments at high spatial resolutions ranging from 50 to 10 *** X-ray energy range of the beamline,5-25 keV,can detect most elements in the periodic *** operating modes were designed to accommodate the experimental requirements of high-energy resolution or high photon flux,respectively.X-ray nanofluorescence,nanodiffraction,and coherent diffraction imaging are developed as the main experimental techniques for *** paper describes the beamline optics,end station configurations,experimental methods under development,and preliminary test *** comprehensive overview aims to provide a clear understanding of the beamline capabilities and potential applications.

关键词： Shanghai synchrotron radiation facility Hard X-ray nanoprobe X-ray nanofocusing

Robust Carbon-Carbon Cleavage in Lignin to Produce Phenol and Cyclohexanone

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Chemical Research in Chinese Universities 2024年第1期40卷 29-35页

作者： WANG Lulin cheng Xiaomeng DONG Minghua LUAN sen WU yuxuan HAN Buxing LIU Huizhen Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesCenter for Carbon Neutral ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

The challenge of breaking 5-5'bonds in lignin,attributed to their high bonding energy,has prompted the development of a new transformation ***,an important model compound for lignin,contains these 5-5'bonds,making it crucial to devise a strategy for their cleavage in lignin *** study introduces a novel method for transforming biphenyl,involving selective hydrogenation to cyclohexylbenzene by Ni/SiO2 catalyst,followed by its oxidation to phenol and cyclohexanone through a radical *** demonstrate that the catalysts with small particles have strong catalytic activity,while there is little difference in *** reason for the high selectivity of cyclohexylbenzene is due to the limited adsorption of cyclohexylbenzene on Ni/*** work presents a fresh approach to breaking resilient C-C bonds in lignin.

关键词： Lignin 5-5'Bond Ni/SiO_(2) Phenol