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Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

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Photonics Research 2024年第5期12卷 941-946页

作者： MENGTING HE YUJING CAO juNJIE LIN ZHIPING ju BOTAO wu E wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Photon Technology(Zhejiang)Co. Ltd.Jiaxing 314100China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200000China Department of Physics and shanghai Key Laboratory for Magnetic Resonance East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of *** this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control *** demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 *** current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

关键词： emitter carbide photon

Surface Topological Glycosylation-Mediated Mucoadhesion of Bacteria

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Chinese Journal of Chemistry 2024年第13期42卷 1447-1455页

作者： Xiao Kuang Xiaobing Liu ju Chen Wenyan Lv Mengmeng Zhang Huan Chen Feng wu Jinyao Liu School of Life Sciences Shanghai UniversityShanghai 200444China shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine Institute of Molecular MedicineState Key Laboratory of Systems Medicine for CancerRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and National Center for Translational MedicineShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234China

Sugar moieties present on bacterial surface serve as pivotal regulators of bacterial *** adjusting the abundance and distribution of surface sugar moieties can offer an important approach to manipulating bacterial behavior,but has been proven to be ***,surface topological glycosylation is reported to mediate the interaction of bacteria with mucous *** functionalized by sugar moieties with different branching are synthesized through iterative Michael addition and amide condensation *** a copper-catalyzed azide-alkyne cycloaddition,the resulting compounds with different branching structures can be attached onto bacterial surface that is modified with azido *** a proof-of-concept study,a set of topologically glycosylated probiotics(TGPs)is prepared using linear,two-branched,and tetra-branched compounds,*** interaction between mucin and TGPs was studied and the results demonstrate that,compared to unmodified bacteria,TGPs exhibit an enhanced adhesive capacity to mucin,which increases with the branching *** binding trend is observed in ex vivo colonic mucus adhesion experiments and bacteria glycosylated with tetra-branched compounds display the highest binding *** work proposes a chemical method to tune the abundance and distribution of sugar moieties on bacteria,providing unique significant insights into the manipulation of bacterial behavior through surface modification.

关键词： Topochemistry Bacteria Glycosylation Surface modification Mucoadhesion Click chemistry

Photocatalytic vinyl radical-mediated multicomponent 1,4-/1,8-carboimination across alkynes and olefins/(hetero)arenes

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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan Li Yu-Shi Jiang Xue-Ling Luo Xuming Ran Yuqiang Li Dong wu Cheng-Xue Pan Peng-ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China shanghai Artificial Intelligence Laboratory Shanghai200433China The institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer *** reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated *** strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and *** the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive *** revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl *** discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

End-to-End Paired Ambisonic-Binaural Audio Rendering

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IEEE/CAA Journal of Automatica sinica 2024年第2期11卷 502-513页

作者： Yin Zhu Qiuqiang Kong junjie Shi Shilei Liu Xuzhou Ye ju-Chiang Wang Hongming Shan junping Zhang shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan UniversityShanghai 200433China Beijing ByteDance Technology Co.Ltd. Shanghai 201102China. Chinese University of Hong Kong Hong KongChina IEEE institute of Science and Technology for Brain-Inspired Intelligence and MOE Frontiers Center for Brain Science Fudan UniversityShanghai 200433 shanghai Center for Brain Science and Brain-Inspired Technology Shanghai 200031China

Binaural rendering is of great interest to virtual reality and immersive media. Although humans can naturally use their two ears to perceive the spatial information contained in sounds, it is a challenging task for machines to achieve binaural rendering since the description of a sound field often requires multiple channels and even the metadata of the sound sources. In addition, the perceived sound varies from person to person even in the same sound field. Previous methods generally rely on individual-dependent head-related transferred function(HRTF)datasets and optimization algorithms that act on HRTFs. In practical applications, there are two major drawbacks to existing methods. The first is a high personalization cost, as traditional methods achieve personalized needs by measuring HRTFs. The second is insufficient accuracy because the optimization goal of traditional methods is to retain another part of information that is more important in perception at the cost of discarding a part of the information. Therefore, it is desirable to develop novel techniques to achieve personalization and accuracy at a low cost. To this end, we focus on the binaural rendering of ambisonic and propose 1) channel-shared encoder and channel-compared attention integrated into neural networks and 2) a loss function quantifying interaural level differences to deal with spatial information. To verify the proposed method, we collect and release the first paired ambisonic-binaural dataset and introduce three metrics to evaluate the content information and spatial information accuracy of the end-to-end methods. Extensive experimental results on the collected dataset demonstrate the superior performance of the proposed method and the shortcomings of previous methods.

关键词： Ambisonic attention binaural rendering neural network

Superplastic Tension Behavior of Dissimilar TC4/SP700 Laminate through Diffusion Bonding

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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 353-363页

作者： Qianwen Zhang Tianle Li Yanbin Han Wei Zheng Xifeng Li Jianjun wu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072China AVIC Xi’an Aircraft Industry Group Company Ltd Xi’an710089China institute of Forming Technology and Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200030China

Superplastic forming is a practical method to manufacture complex-shaped parts of titanium alloys with large *** parts of dissimilar titanium alloys fabricated by superplastic forming can achieve excellent performance by combining the advantages of *** work displays the superplastic tension behavior and microstructural evolution of dissimilar TC4/SP700 laminate prepared by the diffusion bonding *** titanium alloys can achieve metallurgical bonding at parameters of 800℃/1 h/5 *** for dynamic recrystallization and grain growth behaviors upon superplastic tension,stress-induced phase transformation plays an important role inαtoβphase transformation apart from the elevated *** superplastic deformation can be attributed to the grain boundary sliding accommodated multiplex motion of *** addition,the retained strengths of all dissimilar TC4/SP700 laminates after superplastic deformation with different strain rates and temperatures range from 807 to 890 MPa.

关键词： TC4/SP700 laminate Diffusion bonding Microstructure Superplastic tension Strength

Grain Growth Kinetics and Debye Temperature of Nanometer TiO_2 Powders Prepared by a Sol-gel Process

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Journal of Materials Science & Technology 1994年第3期10卷 213-216页

作者： ju LUO Xingzhao DING Benpei CHEN and Jie KONG(institute of Solid State Physics, academia sinica, Hefei, 230031, China)Yuanda DONG(Dept. of metallurgy and Materials, shanghai University of Technology, shanghai, 200072, China) Inst of Solid State Physics Academia Sinica Hefei China

The development of microstructure of nanometer TiO2 powders prepared by a sol-gel process was systematically studied. Grain growth was mon itored using X-ray diffraction (XRD) and transmission electron microscopy (TEM). and the Debye temperature of anatase crystallites was determined. It was found that the grain size of the powders increased slowly with annealing temperature up to 773 K. but grew rapidly in the temperature range of 773-1273K. The activation energies (Ea) for the growth of anatase crystallites in the two temperature regions were calculated to be 16 and 90 kJ / mol, respectively. The Debye temperatures of nanocrystalline anatase powders were all lower than that of microcrystalline anatase. which implies that the bonding force between Ti and O atoms in nanocrystalline TiO2 shourd be smaller than that in microcrystalline state. However. it was noted that the Debye temperature of nanocrystalline anatase increased with the decrease of grain size. This may be attributed to the enhancement in atomic bonding force due to the existence of high surface tension in nanocrystalline powders

关键词： Powders

Photochemistry of endo and exo electronic configurations of biphenylyl methyl propanal

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Chinese Journal of Chemistry 1990年第5期8卷 435-445页

作者： wu,Guo-Sheng YIN,He-Qun shanghai institute of Organic Chemistry,academia sinica,shanghai 200032 shanghai institute of Organic Chemistry Academia Sinica Shanghai 200032

Both direct and sensitized irradiations of the endo title compound lead to a decarbony- lation product,4-isopropylbiphenyl,via Norrish Type 1 reaction,while the exo isomer gives a carbene intermediate and subsequently formaldehyde 2-biphenylyl isopropyl hemiacetal,which in turn gradually decomposes to dimethyl phenylbenzyl alcohol at room *** triplet pathway dominates the photoreaction of the exo *** singlet and triplet lifetimes of the reactant are found to be 0.29 ns and 5.4μs,respectively.~3(n,π~*),~1(n,π~*),~3(π,π~*)electronic configurations of the exo isomer and ~3(π,π~*)of the endo isomer are photochemically active,but ~1(π,π~*)of the endo isomer shows indirect photoreactivity.

关键词： Photochemistry of endo and exo electronic configurations of biphenylyl methyl propanal

晶粒尺寸对Zn/ZSM-5沸石催化烯烃转化性能的影响

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石油学报（石油加工） 2024年第1期40卷 23-36页

作者：于梦楠潘涛鞠雅娜张然吴培吴志杰中国石油大学(北京)重质油国家重点实验室和CNPC催化重点实验室北京102249 中国石油石油化工研究院北京100195

将催化裂化汽油中的烯烃转化为高辛烷值的芳烃或异构烷烃是生产国Ⅵ标准清洁汽油的有效途径。锌改性ZSM-5(Zn/ZSM-5)分子筛是目前最好的烯烃芳构化催化剂。通过调整沸石的晶粒尺寸,系统地考察了不同粒径的ZSM-5沸石的酸性与烯烃选择性... 详细信息

将催化裂化汽油中的烯烃转化为高辛烷值的芳烃或异构烷烃是生产国Ⅵ标准清洁汽油的有效途径。锌改性ZSM-5(Zn/ZSM-5)分子筛是目前最好的烯烃芳构化催化剂。通过调整沸石的晶粒尺寸,系统地考察了不同粒径的ZSM-5沸石的酸性与烯烃选择性转化之间的构效关系。XRD、SEM、TEM、UV-Vis、XPS、FT-IR和NH3-TPD表征结果表明:ZSM-5的晶粒尺寸影响分子筛的酸性位分布,最小晶粒尺寸为100~200 nm的Zn/ZSM-5沸石具有最高ZnOH+活性物种的相对含量(Zn物种的57%)和较低的Bronsted酸与Lewis酸之比(A_(B)/A_(L)=0.15)。在反应温度350℃、液体进料液时体积空速(LHSV)为1.5 h^(-1)、H_(2)(g)和1-己烯(l)体积比为600、氢压为0.1和2.0 MPa条件下,该Zn/ZSM-5沸石催化剂在1-己烯加氢转化反应中分别表现出较高的芳烃选择性(17.2%)和异构烷烃选择性(50.0%)。这些数据表明,减小ZSM-5沸石晶粒尺寸有利于促进催化裂化汽油中烯烃向高辛烷值组分进行选择性转化。

关键词： ZSM-5分子筛烯烃芳构化汽油酸催化

The structure correction,of “8-hydroxysub-spinosin” and synthesis of 5-hydroxy-damnacanthol-ω-ethyl ether

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Chinese Journal of Chemistry 1991年第4期9卷 365-372页

作者： YU,ju-Rong CAI,jun-Chao GAO,Yi-Sheng shanghai institute of Materia Medica,academia sinica,shanghai 200031 shanghai institute of Materia Medica Academia Sinica Shanghai 200031

8-Hyaroxysubspinosin was elucidated as 2,8-dihydroxy-3-ethoxymethyl-1-methoxy- anthraquinone(2)in the ***,the structure revision and synthesis of 8-hydroxysubspinosin were *** should be revised to 3,5-dihydroxy-2-ethoxymethyl-1-methoxyanthraquinone (5),i.e.5-hydroxydamnacanthol-ω-ethyl ether by comparison with the synthetic sample.5 was syn- thesized by alkylation of 3-bromo-7-methoxyphthalide(10)with 2,6-dimethoxytoluene in the presence of stannic chloride,followed by reductive clcavagc,cyclization,oxidation,demethylation,selective acetylation,methylation,bromination and condensation with sodium *** isomer 1,3- dihydroxy-2-ethoxymethyl-5-methoxyanthraquinone(5b)was also obtained.

关键词： The structure correction,of hydroxysub-spinosin ethyl ether and synthesis of 5-hydroxy-damnacanthol