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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

Dynamic lithium-compensation mechanism for densification of garnet-type Li_(7)La_(3)Zr_(2)O_(12)electrolyte by Li_(2)O atmosphere buffer pair

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Nano Research 2024年第7期17卷 6184-6191页

作者： Chujun Zheng Ya Chen Haoxin Dong Yan lu Jun Jin Zhaoyin wen CAS Key Laboratory of Materials for Energy Conversion Shanghai Institute of CeramicsChinese Academy of ScienceShanghai 200050China State Key Lab High Performance Ceram and Superfine Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Solid-state lithium metal batteries are one of the most promising options for next-generation batteries pursuing high-energy density and ***,the inevitable volatilization of lithium compounds during sintering leads to low relative density and low ionic conductivity of solid-state ***,the dynamic lithium-compensation mechanism is proposed to facilitate the densification of Ta-substituted garnet-type electrolyte(Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZT))through the reversible manipulating of Li_(2)O ***_(2)ZrO_(3)is used as mother powder additive,which reacts with Li_(2)O in sintering atmosphere and forms Li_(6)Zr_(2)O_(7).Li_(2)ZrO_(3)/Li_(6)Zr_(2)O_(7)buffer pair manipulates the sintering Li_(2)O atmosphere,which is vital for LLZT,within the Li_(2)O partial pressure range corresponding to Li_(2)ZrO_(3)and Li_(6)Zr_(2)O_(7).Furthermore,the reversibility mechanism of buffer pair for Li_(2)O absorption and release is *** obtained LLZT exhibits a relative density of over 96%and an ionic conductivity exceeding 7×10^(−4)S·cm^(−1)with no abnormal grain *** symmetric cell demonstrates an excellent lithium dendrite suppressing ability(stable cycling at a current density of 0.3 mA·cm^(−2)for over 1000 h).Such dynamic lithium-compensation strategy has been successfully applied in atmosphere manipulation of LLZT sintering process,which reduces the dependence of LLZT on the Li_(2)O atmosphere,making it conducive to large-scale preparation of electrolyte ceramics.

关键词： solid-state batteries garnet-type electrolyte high-density electrolyte dynamic lithium-compensation buffer pair

Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng Chen Mao-Mao Zhang wen-Jing Xiao Liang-Qiu lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University Wuhan Institute of Photochemistry and Technology State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics (LICP)Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Chiral α-tertiary amines and related azacycles are commonly found in many natural products, pharmaceuticals and agrochemicals [1]. Copper-catalyzed asymmetric propargylic amination(APA) reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2] and van Maarseveen et al. [3] in 2008.

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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-lu Zhang wen-Bo He Xiu-Qin Hu Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo Li Feng Jiang Zhengyi Jiang Zige Tian Tian Qiu Tao Zhang Qiuling wen Xizhao lu Jing lu Hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

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Postoperative pneumocranium after endoscopic transnasal optic canal decompression

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 973-975页

作者： Sheng-Jian lu Bo Yu wen-Can Wu The Eye Hospital School of Ophthalmology&OptometryWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

Dear Editor,We present the first time,a case of a patient developed cerebrospinal fluid(CSF)leak and pneumocranium following optic canal decompression(OCD).INTRODUCTION Indirect traumatic optic neuropathy(ITON)impairs visual functions and quality of *** transnasal optic canal decompression(ETOCD)is one of the standard treatment strategies for the *** the ETOCD,the optic nerve sheath are usually incised for sufficient decompression of optic nerve after removal of optic canal,which is associated with complications like CSF leakage,ophthalmic artery injury,and optic nerve injury[1].Generally,the mild CSF leak is common and can heal spontaneously using conventional treatment,the severe CSF leak requires surgical repair[2].

关键词： decompression nasal traumatic

Establishment of a humanized ST6GAL1 mouse model for influenza research

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Animal Models and Experimental Medicine 2024年第3期7卷 337-346页

作者： Lyu Chao Han Feng Gao Qian Lv Limin lu Ziwei lu Shuangshuang Li Xiaoyan Hu Yuechao Yang Mengjie Zhao Yingze Liu Jun lu Xuancheng duo Shuguang National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases Chinese Center for Disease Control and PreventionBeijingChina Institute of Zoology Chinese Academy of SciencesBeijingChina NHC Key Laboratory of Biosafety National Key Laboratory of Intelligent Tracking and Forecasting for Infectious DiseasesNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Zhejiang Provincial Key Laboratory of Medical Genetics Key Laboratory of Laboratory MedicineMinistry of EducationSchool of Laboratory Medicine and Life SciencesWenzhou Medical UniversityWenzhouChina

Background:This study aimed to construct and characterize a humanized influenza mouse model expressing ***:Humanized fragments,consisting of the endothelial cell-specific K18 promoter,human ST6GAL1-encoding gene,and luciferase gene,were microinjected into the fertilized eggs of *** manipulated embryos were transferred into the oviducts of pseudopregnant female *** offspring were identified using *** exhibiting elevated expression of the hST6GAL1 gene were selectively bred for propagation,and in vivo analysis was performed for *** of the humanized gene was tested by performing immunohistochemical(IHC)*** and biochemical analyses using the whole blood and serum of humanized hST6GAL1 mice were ***:Successful integration of the human ST6GAL1 gene into the mouse genome led to the overexpression of human SiaT *** mice were identified as carrying copies of the humanized gene,and the in vivo analysis indicated that hST6GAL1gene expression in positive mice mirrored influenza virus infection *** IHC results revealed that hST6GAL1 was expressed in the lungs of humanized ***,the hematologic and biochemical parameters of the positive mice were within the normal ***:A humanized influenza mouse model expressing the hST6GAL1 gene was successfully established and characterized.

关键词： hST6GAL1 humanized mice influenza animal model

Mathematical model and numerical investigation of the influence of spray drying parameters on granule sizes of mold powder

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Particuology 2024年第2期85卷 280-295页

作者： Fei Zhang Youyu lu Shaoyan Zhu Funian Han Guanghua wen Ping Tang Zibing Hou College of Materials Science and Engineering Chongqing UniversityChongqing400044China Guizhou Academy of Testing and Analysis Guizhou Academy of SciencesGuiyang550014China

In this work,the formation mechanism of the droplet-to-granule was investigated in detail based on mold powder manufacturing.A specific mathematical model of two-stage spray drying was established to describe droplet and granule motion,heat and mass transfer,and granule morphology during spray ***,the relationships between spray drying parameters(inlet temperature,atomization pres-sure,slurry mass flow rate)and the properties of the drying tower(temperature and velocity fields)and mold powder granules(temperature,evaporation rates,moisture content,and diameter)were simulated and calculated using ANSYS/Fluent *** ensure that the granule size of mold powder was controlled within the ideal range(0.2-0.6 mm)for producing granules with appropriate mechanical and metallurgical properties,the following optimum spray drying parameters were chosen based on the results of the numerical simulation:inlet temperatures,873 K;slurry atomization pressure,1.8 MPa;slurry mass flow rate,0.05 kg *** these parameters,the slurry mass flow rate has the most significant effect on granule size.

关键词： Mold powder slurry Spray drying parameters Mathematical model Numerical simulation Granule sizes

Improving Thermal-oxidative Aging Resistance of Styrene-butadiene Rubber by Antioxidant Loaded Silica Aerogel

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Chinese Journal of Polymer Science 2024年第8期42卷 1198-1209页

作者： Xue-Fei Ping Yu Wang lu Liu Fu-Yong Liu Hong-Wei He Pi Wang wen-wen Yu Qiang Zheng College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China

The antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine(4010NA)was dissolved in ethanol and impregnated into silica aerogel(SAG)via vacuum-pressure cycles,yielding composite particles(A-N)with enhanced sustained-release and reinforcing *** effect of A-N on the mechanical properties and thermal-oxidative aging resistance of styrene-butadiene rubber(SBR)vulcanizates was *** and BET assessments indicated that the loading efficiency of 4010NA in SAG reached 14.26%within ethanol's solu bility *** A-N into SBR vulcanizates significantly elevated tensile strength by 17.5%and elongation at break by 41.9%over those with fumed silica and ***,A-N notably enhanced the thermal-oxidative aging resistance of *** aging for 96 h at 100℃,the tensile strength and elongation at break of SBR with A-N sustained 70.09%and 58.61%of their initial values,respectively,with the retention rate of elongation at break being 62.8%higher than that of SBR with fumed silica and free *** study revealed that A-N composite particles significantly inhibited the crosslinking in SBR's molecular chains,reducing hardening and embrittlement during later thermal-oxidative aging stages.

关键词： Styrene-butadiene rubber Silica aerogel Loading modification Thermal-oxidative aging

Pt nanoclusters modified porous g-C_(3)N_(4)nanosheets to significantly enhance hydrogen production by photocatalytic water reforming of methanol

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Chinese Journal of Chemical Engineering 2024年第2期66卷 40-50页

作者： Yi-Fei Liang Jin-Rong lu Shang-Kun Tian wen-Quan Cui Li Liu Hebei Provincial Key Laboratory of Environmental Photocatalytic and Electrocatalytic Materials College of Chemical EngineeringNorth China University of Science and TechnologyTangshan 063210China

For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild *** attention has been paid to gC_(3)N_(4)as a promising photocatalyst for the generation of *** improve the separation of photogenerated charge,porous nanosheet g-C_(3)N_(4)was modified with Pt nanoclusters(Pt/g-C_(3)N_(4))through impregnation and following photo-induced *** catalyst showed excellent photocatalytic activity of water reforming of methanol fo r hydrogen production with a 17.12 mmol·g^(-1)·h^(-1)rate at room temperature,which was 311 times higher than that of the unmodified g-C_(3)N_(4).The strong interactions of Pt-N in Pt/g-C_(3)N_(4)constructed effective electron transfer channels to promote the separation of photogenerated electrons and holes *** addition,in-situ infrared spectroscopy was used to investigate the intermediates of the hydrogen production reaction,which proved that methanol and water eventually turn into H_(2)and CO_(2)via formaldehyde and *** study provides insights for understanding the photocatalytic hydrogen production in the water reforming of methanol.

关键词： Water reforming of methanol Photocatalysis g-C_(3)N_(4) Pt nanoclusters Hydrogen production