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高抗激光损伤阈值光栅后处理抛光技术研究

光学精密工程 2023年第14期31卷 2071-2079页

作者：洪小兰姜晨上海理工大学机械工程学院上海200093

脉冲压缩光栅是实现高能量激光的核心光学元器件,其制造过程中产生的表面污染物和微结构缺陷成为限制高功率激光系统发展的技术瓶颈,为了提升光栅的激光诱导损伤阈值,提出利用磁性复合流体进行脉冲压缩光栅(PCG)后处理抛光研究。对抛光... 详细信息

脉冲压缩光栅是实现高能量激光的核心光学元器件,其制造过程中产生的表面污染物和微结构缺陷成为限制高功率激光系统发展的技术瓶颈,为了提升光栅的激光诱导损伤阈值,提出利用磁性复合流体进行脉冲压缩光栅(PCG)后处理抛光研究。对抛光前后光栅样品的微观结构,表面形貌、表面粗糙度、衍射效率和激光诱导损伤阈值等参数进行测量,进行抛光前后光栅表面质量和光栅性能的评估。研究发现,磁性复合流体抛光能够在不破坏实际光栅结构的前提下抑制加工过程产生的毛刺,微结构缺陷等;经3 min抛光后,光栅顶部表面粗糙度从21.36 nm下降到3.73 nm;激光诱导损伤阈值从2.8 J/cm^(2)提高到3.8 J/cm^(2),抗激光损伤性能提升35.7%,且不影响衍射效率。实验结果表明:磁性复合流体抛光是一种可以提高光栅元件表面质量,提升光栅元件光学性能的有效方法。

关键词：脉冲压缩光栅多层介质膜光栅磁性复合流体激光诱导损伤阈值表面形貌

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Layer-by-layer fabrication of montmorillonite coating immobilizing Cu_(2)O nanoparticles for continuously catalyzing glycerol to dihydroxyacetone

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Chinese Journal of Chemical Engineering 2024年第4期68卷 263-275页

作者： Kejin Li Jiahui Liu Dajian Li xiaolan Chen Chunhui Zhou Research Group for Advanced Materials&Sustainable Catalysis(AMSC) State Key Laboratory Breeding Base of Green Chemistry-Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310032China Qing Yang Institute for Industrial Minerals Qingyang 242804China Engineering Research Center of Non-metallic Minerals of Zhejiang Province Zhejiang Institute of Geology and Mineral ResourcesHangzhou 310007China

Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer,increased yield,safety,and simplicity of ***,immobilizing catalysts in microreactors remains *** this investigation,a technique for creating Cu_(2)O/montmorillonite catalyst coating,using electrostatic attraction for layer-by-layer self-assembly,was *** montmorillonite film's morphology and thickness could be efficiently regulated by adjusting the degree of exfoliation and surface charge of montmorillonite,alongside layer-by-layer coating *** Cu_(2)O nanoparticles were immobilized using the flow deposition *** resulting Cu_(2)O@montmorillonite-film-coated capillary microreactor successfully transformed glycerol into *** conversion of glycerol and product selectivity could be controlled by adjusting the molar ratio of reactants,temperature,residence time,and Cu_(2)O *** maximum glycerol conversion observed was 47.6%,with a 27%selectivity toward *** study presents a technique for immobilizing montmorillonite-based catalyst coatings in capillary tubing,which can serve as a foundation for the future application of microreactors in glycerol conversion.

关键词： Microreactor Coating Montmorillonite Glycerol Cu_(2)O

Designing highly transparent cerium doped Y2O3 ceramics with high mechanical and thermal properties for UV-shielding in extreme conditions

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Journal of Advanced Ceramics 2024年第7期13卷 1032-1042页

作者： Cong Zhang Jianqi Qi xiaolan Zhou Zhonghua Lu Tiecheng Lu College of Physics Sichuan UniversityChengdu 610064China Key Laboratory of High Energy Density Physics of Ministry of Education Sichuan UniversityChengdu 610064China Key Laboratory of Radiation Physics and Technology of the Ministry of Education Sichuan UniversityChengdu 610064China

Ultraviolet(UV)radiation poses risks to both human health and *** response to the urgent demand for UV-shielding across various applications,extensive endeavors have been dedicated to developing UV-shielding materials spanning from wide-bandgap semiconductors to organo-inorganic composite ***,existing UV shielding materials,though suitable for daily use,cannot meet the demands of extreme *** this work,we incorporated CeO_(2)as a UV absorber into Y_(2)O_(3)transparent ceramics for *** effect of CeO_(2)concentration on the optical,mechanical,and thermal properties of Y_(2)O_(3)ceramics was systematically *** findings indicate that CeO_(2)serves not only as a UV absorber but also as an effective sintering aid for Y_(2)O_(3)transparent *** 5 at%Ce-doped Y_(2)O_(3)transparent ceramics exhibit the optimal optical quality,with in-line transmittance of~77%at 800 *** introduction of Ce shifted the UV cutoff edge of Y_(2)O_(3)transparent ceramics from 250 to 375 nm,which was attributed to the visible band absorption of Ce^(4+).This shift grants UV shielding capabilities to Y_(2)O_(3)transparent ceramics,resulting in 100%shielding for ultraviolet C(UVC,100-280 nm)and ultraviolet B(UVB,280-320 nm)and~95%shielding for ultraviolet A(UVA,320-400 nm).The service stability(optical properties)under various corrosive conditions(acid,alkali,UV irradiation,and high temperature)was investigated,confirming the excellent stability of this transparent ceramic UV-shielding material.A comparison of the performance parameters of transparent ceramics with those of traditional UV shielding materials such as glasses,films,and coatings was *** work provides innovative design concepts and an effective solution for UVshielding materials for extreme conditions.

关键词： ultraviolet(UV)-shielding transparent ceramics bandgap engineering thermal properties optical properties

Observations on spontaneous chiral symmetry breaking and the mass gap of QCD in finite volume

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Communications in Theoretical Physics 2024年第9期76卷 44-49页

作者： xiaolan Meng Bolun Hu Yi-Bo Yang University of Chinese Academy of Sciences School of Physical Sciences CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCAS International Centre for Theoretical Physics Asia-Pacific

We present a lattice quantum chromodynamics(QCD) simulation with 2 + 1 + 1 flavor full QCD ensembles using near-physical quark masses and different spatial sizes L, at a ～ 0.055 *** results show that the scalar and pesudoscalar 2-point correlator with a valence pion mass of approximately 230 MeV become degenerated at L ≤ 1.0 fm, and such an observation suggests that the spontaneous chiral symmetry breaking disappears effectively at this point. At the same time, the mass gap between the nucleon and pion masses remains larger than ΛQCDin the entire L ∈ [0.2, 0.7] fm range.

关键词： chiral symmetry breaking confinement lattice QCD

Three-Rigid-Body-Particle Modeling and Optimization of Trajectory and Posture for Alpine Skiing

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Journal of Systems Science & Complexity 2024年第2期37卷 581-608页

作者： ZHANG Yijia FEI Qing YAO xiaolan SUN Jian ZHANG Yanjun CHEN Zhen School of Automation Beijing Institute of TechnologyBeijing 100081China

This paper presents a new study on modeling and optimization of trajectory and posture for the super-giant(SG)slalom of alpine *** is the first time that a Three-Rigid-Body-Particle model based on rigorous derivations and stability analysis is established to represent skiers trajectory and posture characteristics,as it is more accurate than the single-rigid-body model which is commonly used in existing *** addition,the Radau pseudospectral method is applied to solve the trajectory and posture optimization problem in order to obtain better skiing trajectory,skiing posture,and some key kinematic parameters of ***,this paper analyzes the effects of different body types,minimum turning radii,and flexor and extensor strength of knees and hip joint on skiing ***,based on the findings of the study,some advice about how to improve the performance of the SG slalom in view of science and technology is given to skiers and coaches for reference.

关键词： Alpine skiing modeling posture optimization Three-Rigid-Body-Particle model trajectory optimization

Study on trifluoromethanesulfonic acid-promoted synthesis of daidzein: Process optimization and reaction mechanism

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Chinese Journal of Chemical Engineering 2024年第7期71卷 132-139页

作者： Hai Cao Haibin Yang Yanxiong Fang Yuandi Zeng xiaolan Cai Jingjing Ma School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,*** preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesizing daidzein was developed in this *** this article,a two-step synthesis of daidzein(Friedel–Crafts acylation and[5+1]cyclization)was developed via the employment of trifluoromethanesulfonic acid(TfOH)as an effective promoting *** effect of reaction conditions such as solvent,the amount of TfOH,reaction temperature,and reactant ratio on the conversion rate and the yield of the reaction,respectively,was systematically investigated,and daidzein was obtained in 74.0%isolated yield under optimal *** to the facilitating effect of TfOH,the Friedel–Crafts acylation was completed within 10 min at 90℃ and the[5+1]cyclization was completed within 180 min at 25℃.In addition,a possible reaction mechanism for this process was *** results of the study may provide useful guidance for industrial production of daidzein on a large scale.

关键词： Synthesis Optimal design Chemical processes Reaction mechanism

Computational and dark-field ghost imaging with ultraviolet light

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Photonics Research 2024年第2期12卷 226-234页

作者： JIAQI SONG BAOLEI LIU YAO WANG CHAOHAO CHEN XUCHEN SHAN xiaolan Zhong LING-AN WU FAN WANG School of Physics Beihang UniversityBeijing 102206China Australian Research Council Centre of Excellence for Transformative Meta-Optical Systems Department of Electronic Materials EngineeringResearch School of PhysicsThe Australian National UniversityCanberraACT 2600Australia Institute of Physics Chinese Academy of SciencesBeijing 100190China

Ultraviolet(UV)imaging enables a diverse array of applications,such as material composition analysis,biological fluorescence imaging,and detecting defects in semiconductor ***,scientific-grade UV cameras with high quantum efficiency are expensive and include complex thermoelectric cooling ***,we demonstrate a UV computational ghost imaging(UV-CGI)method to provide a cost-effective UV imaging and detection *** applying spatial–temporal illumination patterns and using a 325 nm laser source,a singlepixel detector is enough to reconstruct the images of *** use UV-CGI to distinguish four UV-sensitive sunscreen areas with different densities on a ***,we demonstrate dark-field UV-CGI in both transmission and reflection *** only collecting the scattered light from objects,we can detect the edges of pure phase objects and small scratches on a compact *** results showcase a feasible low-cost solution for nondestructive UV imaging and *** combining it with other imaging techniques,such as hyperspectral imaging or time-resolved imaging,a compact and versatile UV computational imaging platform may be realized for future applications.

关键词： ghost illumination versatile

Duplicated chalcone synthase(CHS)genes modulate flavonoid production in tea plants in response to light stress

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Journal of Integrative Agriculture 2024年第6期23卷 1940-1955页

作者： Mingzhuo Li Wenzhao Wang Yeru Wang Lili Guo Yajun Liu xiaolan Jiang Liping Gao Tao Xia State Key Laboratory of Tea Plant Biochemistry and Utilization Anhui Agricultural UniversityHefei 230036China School of Life Sciences Anhui Agricultural UniversityHefei 230036China College of Horticulture Northwest A&F UniversityYangling 712100China Department of Plant and Microbial Biology North Carolina State UniversityRaleigh 27606NCUSA

In tea plants,the abundant flavonoid compounds are responsible for the health benefits for the human body and define the astringent flavor *** the downstream mechanisms of flavonoid biosynthesis have been extensively studied,the role of chalcone synthase(CHS)in this secondary metabolic process in tea plants remains less *** this study,we compared the evolutionary profile of the flavonoid metabolism pathway and discovered that gene duplication of CHS occurred in tea *** identified three CsCHS genes,along with a CsCHS-like gene,as potential candidates for further functional *** the CsCHS-like gene,the CsCHS genes effectively restored flavonoid production in Arabidopsis ***,CsCHS transgenic tobacco plants exhibited higher flavonoid compound accumulation compared to their wild-type *** notably,our examination of promoter and gene expression levels for the selected CHS genes revealed distinct responses to UV-B stress in tea *** findings suggest that environmental factors such as UV-B exposure could have been the key drivers behind the gene duplication events in CHS.

关键词： tea flavonoids biosynthesis CHS gene duplication UV-B stress

An Assembly of Pyrano[3,2-b]indol-2-ones via NHC-Catalyzed[3+3]Annulation of Indolin-3-ones with Ynals

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Chinese Journal of Chemistry 2024年第13期42卷 1487-1492页

作者： Xia Wang Shulei Zhang Shao-Jie Wang Hao An xiaolan Xin Haonan Lin Zhifeng Tu Shenci Lu Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Instituteof Biomedical Materials and Engineering(SiBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China School of Chemistry and Chemical Engineering Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

We report herein an unprecedented N-heterocyclic carbene-catalyzed formal[3+3]annulation of ynals with N-Ts indolin-3-ones under the oxidation condition affording the functionalized pyrano[3,2-b]*** alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this *** method features a broad substrate scope and mild conditions,including axially chiral skeletons with suitable substitutions.

关键词： N-Heterocyclic carbene Annulation Organocatalysis Atropisomerism Carbazole Aldehydes Heterocycles Asymmetric catalysis