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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 *** 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 ***, the general condition to obtain fluorescent single photons with subnatural linewidth is *** 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

Creating one-line hybrid crops by synthetic apomixis

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Molecular Plant 2024年第1期17卷 16-18页

作者： Ronghong liang Caixia gao New Cornerstone Science Laboratory Center for Genome EditingInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing100101China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing100049China

Hybrid breeding plays an important role in increasing crop yields by taking advantage of hybrid vigor,which helps crops grow with superior yields across various climates and contributes to ensuring secure food *** seed production is relatively straightforward and simple in cross-pollinating plants such as maize but is difficult in self-pollinating plants such as rice,wheat,and ***,breeders have developed a three-line breeding strategy,utilizing a sterile line,a maintainer line,and a restorer line,for breeding hybrid rice(Figure 1A;Yuan,1966).

关键词： breeding crops sterile

Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization

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Chinese Journal of Chemical Engineering 2024年第3期67卷 16-26页

作者： Chenhao Wei Di gao Guohao Zhang liang Zhao Jinsen gao chunming Xu The State Key Lab of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and ***,the increasing market demand of xylene has put forward higher requirements for new generation of *** increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was *** with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and *** was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst *** the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the ***,the state of loaded Zn was also affected by mesopores spatial *** the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid *** work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst.

关键词： 1-Hexene aromatization Alkali treatment Xylene selectivity Mesopores Zinc state

Mathematical Modeling and a Multiswarm Collaborative Optimization Algorithm for Fuzzy Integrated Process Planning and Scheduling Problem

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Tsinghua Science and Technology 2024年第2期29卷 285-304页

作者： Qihao Liu Cuiyu Wang Xinyu Li liang gao State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Considering both process planning and shop scheduling in manufacturing can fully utilize their complementarities,resulting in improved rationality of process routes and high-quality and efficient production. Hence,the study of Integrated Process Planning and Scheduling (IPPS) has become a hot topic in the current production field. However,when performing this integrated optimization,the uncertainty of processing time is a realistic key point that cannot be neglected. Thus,this paper investigates a Fuzzy IPPS (FIPPS) problem to minimize the maximum fuzzy completion time. Compared with the conventional IPPS problem,FIPPS considers the fuzzy process time in the uncertain production environment,which is more practical and realistic. However,it is difficult to solve the FIPPS problem due to the complicated fuzzy calculating rules. To solve this problem,this paper formulates a novel fuzzy mathematical model based on the process network graph and proposes a MultiSwarm Collaborative Optimization Algorithm (MSCOA) with an integrated encoding method to improve the optimization. Different swarms evolve in various directions and collaborate in a certain number of iterations. Moreover,the critical path searching method is introduced according to the triangular fuzzy number,allowing for the calculation of rules to enhance the local searching ability of MSCOA. The numerical experiments extended from the well-known Kim benchmark are conducted to test the performance of the proposed MSCOA. Compared with other competitive algorithms,the results obtained by MSCOA show significant advantages,thus proving its effectiveness in solving the FIPPS problem.

关键词： Integrated Process Planning and Scheduling(IPPS) fuzzy processing time fuzzy completion time MultiSwarm Collaborative Optimization Algorithm(MSCOA)

A Hybrid Level Set Optimization Design Method of Functionally Graded Cellular Structures Considering Connectivity

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Computers, Materials & Continua 2024年第4期79卷 1-18页

作者： Yan Dong Kang Zhao liang gao Hao Li The State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China Institute of Systems Engineering China Academy of Engineering PhysicsMianyang621900China

With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying microstructures has grown ***,a critical challenge is encountered in the design of these structures–the absence of robust interface connections between adjacent microstructures,potentially resulting in diminished efficiency or macroscopic failure.A Hybrid Level Set Method(HLSM)is proposed,specifically designed to enhance connectivity among non-uniform microstructures,contributing to the design of functionally graded cellular *** HLSM introduces a pioneering algorithm for effectively blending heterogeneous microstructure ***,an interpolation algorithm is presented to construct transition microstructures seamlessly connected on both ***,the algorithm enables the morphing of non-uniform unit cells to seamlessly adapt to interconnected adjacent *** method,seamlessly integrated into a multi-scale topology optimization framework using the level set method,exhibits its efficacy through numerical examples,showcasing its prowess in optimizing 2D and 3D functionally graded materials(FGM)and multi-scale topology *** essence,the pressing issue of interface connections in complex structure design is not only addressed but also a robust methodology is introduced,substantiated by numerical evidence,advancing optimization capabilities in the realm of functionally graded materials and cellular structures.

关键词： Hybrid level set method functionally graded cellular structure connectivity interpolated transition optimization design

Hybrid effect on mechanical properties and high-temperature performance of copper matrix composite reinforced with micro-nano dual-scale particles

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Journal of Materials Science & Technology 2024年第5期172卷 94-103页

作者： Xingde Zhang Yihui Jiang Fei Cao Tian Yang Fan gao Shuhua liang School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Conducting Materials and Composite Technology Ministry of EducationXi’an University of TechnologyXi’an 710048China Shaanxi Province Key Laboratory of Electrical Materials and Infiltration Technology Xi’an University of TechnologyXi’an 710048China

A dual-scale hybrid HfB_(2)/Cu-Hf composite with HfB_(2) microparticles and Cu_(5) Hf nanoprecipitates was designed and *** contribution of the hybrid effect to the mechanical properties and high-temperature performances was studied from macro and micro perspectives,*** hybrid of dual-scale particles can make the strain distribution of the composite at the early deformation stage more uniform and delay the strain concentration caused by the HfB_(2) *** dislocation pinning of HfB_(2) particles and the coherent strengthening of Cu_(5) Hf nanoprecipitates simultaneously play a strengthening role,but the strength of the hybrid composite is not a simple superposition of two strengthening *** addition,both Cu_(5) Hf nanoprecipitates and HfB_(2) microparticles contribute to the high-temperature performance of the composite,the growth and phase transition of nanoprecipitates at high temperature will reduce their contribution to strength,while the stable HfB_(2) particles can inhibit the coarsening of matrix grains and maintain the high-density geometrically necessary dislocations(GNDs)in the matrix,which ensures more excellent high-temperature resistance of the hybrid *** a result,the hy-brid structure can simultaneously possess the advantages of multiple reinforcements and make up for the shortcomings of each ***,a copper matrix composite with high strength,high conductivity,and excellent high-temperature performance is displayed.

关键词： Copper matrix composite HfB 2 particles Hybrid effect High strength and high conductivity High-temperature performance

Strain-promoted S-arylation and alkenylation of sulfinamides using arynes and cyclic alkynes

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Science China Chemistry 2024年第3期67卷 928-935页

作者： Xi Zou Boming Shen gao-lin Li Qian liang Yanhua Ouyang Binghe Yang Peiyuan Yu Bing gao State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringInstitute of Chemical Biology and NanomedicineHunan UniversityChangsha 410082China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China

The conversion of commercially available chiral sulfinamides into pharmaceutically useful chiral sulfoximines via direct SIVfunctionalization is synthetically attractive but challenging due to the competitive reaction of N-functionalization. Herein, we disclose a novel strain-release strategy to access stereospecific and chemoselective SIV-arylation and alkenylation of sulfinamides using arynes and strained cyclic alkynes. This method tolerates an unprecedented chemical diversity of functional groups attached to the nitrogen center(N-R). The origin of the high SIV-selectivity is elucidated by density functional theory calculations, suggesting a stepwise mechanism for the aryne substrates and a concerted mechanism for the cyclic alkynes.

关键词： arylation alkenylation sulfoximines sulfinamides arynes

Five-view three-dimensional reconstructionfor ultrafast dynamic imaging of pulsedradiation sources

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Matter and Radiation at Extremes 2024年第2期9卷 63-73页

作者： Jianpeng gao liang Sheng Xinyi Wang Yanhong Zhang liang Li Baojun Duan Mei Zhang Yang Li Dongwei Hei Department of Engineering Physics Tsinghua UniversityBeijing 100084China National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi’an 710024China

Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights intothe generation and evolution mechanisms of pulsed radiation sources. Owing to the short emission time (∼200 ns) and drastic changes of thepulsed radiation source, it is necessary to acquire projection data within a few nanoseconds in order to achieve clear computed tomography3D imaging. As a consequence, projection data that can be used for computed tomography image reconstruction at a certain moment are oftenavailable for only a few angles. Traditional algorithms employed in the process of reconstructing 3D images with extremely incomplete datamay introduce significant distortions and artifacts into the final image. In this paper, we propose an iterative image reconstruction methodusing cylindrical harmonic decomposition and a self-supervised denoising network algorithm based on the deep image prior method. Weaugment the prior information with a 2D total variation prior and a 3D deep image prior. Single-wire Z-pinch imaging experiments have beencarried out at Qin-1 facility in five views and four frames, with a time resolution of 3 ns for each frame and a time interval of 40 ns betweenadjacent frames. Both numerical simulations and experiments verify that our proposed algorithm can achieve high-quality reconstructionresults and obtain the 3D intensity distribution and evolution of extreme ultraviolet and soft x-ray emission from plasma.

关键词： frames image sources

Glucose-sensitive Membrane with PBA-based Contraction-type Linear Polymer as Chemical Valves Prepared by Surface Grafting

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CHINESE JOURNAL OF POLYMER SCIENCE 2024年第8期42卷 1067-1076页

作者： Zhang, chun-Peng gao, Si-Jia Luo, Ying Zou, Lei Zhang, Yong-Jun Tiangong Univ Sch Mat Sci & Engn State Key Lab Separat Membranes & Membrane Proc Tianjin 300387 Peoples R China Tiangong Univ Sch Pharmaceut Sci State Key Lab Separat Membranes & Membrane Proc Tianjin 300387 Peoples R China Tiangong Univ Cangzhou Inst Cangzhou 061000 Peoples R China Nankai Univ Inst Hepatobiliary Dis Tianjin Key Lab Extracorporeal Life Support Crit D Affiliated Ctr Hosp 3 Tianjin 300170 Peoples R China

Glucose-sensitive membrane has potential application in self-regulating insulin release. Phenylboronic acid (PBA) is a well-known glucose reporter. Unfortunately, most PBA-based glucose-sensitive materials are expansion-type, which are not suitable as chemical valves in membrane pores for self-regulating insulin release. According to a new glucose-sensitive mechanism, we synthesized PBA-based contraction-type glucose-sensitive liner polymer and microgels. Herein, a glucose-sensitive membrane was prepared by grafting PBA-based contraction-type glucose-sensitive linear polymer on the membrane surface. Through adjusting the chain length and chain density, the glucose-sensitivity of the membrane was optimized. The membrane can reversibly regulate insulin release at physiologically relevant glucose concentrations in simulates body fluids and fetal bovine serum. The membrane also has good stability, anti-fouling and biocompatibility. It has potential application in self-regulating insulin release.

关键词： Phenylboronic acid Glucose-sensitive Membrane Surface grafting Insulin PHENYLBORONIC ACID BRUSHES DENSITY CHAINS LENGTH FILM