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Super-resolution Imaging of Telescopic Systems based on Optical-neural Network Joint Optimization

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research in Astronomy and Astrophysics 2024年第9期24卷 167-177页

作者： You-Hong Sun Tao Zhang Hao-Dong Shi Qiang Fu Jia-Nan Liu Kai-Kai Wang Chao Wang research institute of Chongqing Changchun University of Science and TechnologyChangchun 130022China National and Local Joint Engineering research Center for Space Photoelectric technology Changchun University of Science and TechnologyChangchun 130022China The institute of Remote sensing Satellites China Academy of Space Technology(CAST)Beijing 100094China

Optical telescopes are an important tool for acquiring optical information about distant objects,and resolution is an important indicator that measures the ability to observe object ***,due to the effects of system aberration,atmospheric seeing,and other factors,the observed image of ground-based telescopes is often degraded,resulting in reduced *** paper proposes an optical-neural network joint optimization method to improve the resolution of the observed image by co-optimizing the point-spread function(PSF)of the telescopic system and the image super-resolution(SR)*** improve the speed of image reconstruction,we designed a generative adversarial net(LCR-GAN)with light parameters,which is much faster than the latest unsupervised *** reconstruct the PSF trained by the network in the optical path,a phase mask is *** improves the image reconstruction effect of LCR-GAN by reconstructing the PSF that best matches the *** results of simulation and verification experiments show that compared with the pure deep learning method,the SR image reconstructed by this method is rich in detail and it is easier to distinguish stars or stripes.

关键词： Techniques:image processing Telescopes Stars:imaging

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Rational design of AgGaS/ZnS/ZnS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu Z.Z.Fu Y.Y.Chen H.Q.Dai Z.Hu W.L.Zhang R.Q.Guo institute for Electric light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China institute of Future lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu research institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/ZnS/ZnS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in Zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between Zn cation diffusion and ZnS shelling ***,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

Role of catalyst surface-active sites in the hydrogenation ofα,β-unsaturated aldehyde

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Frontiers of Chemical Science and Engineering 2024年第6期18卷 41-69页

作者： Haixiang Shi Tongming Su Zuzeng Qin Hongbing Ji School of Chemistry and Chemical Engineering Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification TechnologyGuangxi UniversityNanning 530004China Zhejiang Green Petrochemical and light Hydrocarbon Transformation research institute Zhejiang University of TechnologyHangzhou 310014China

As an important technology in fine chemical production,the selective hydrogenation ofα,β-unsaturated aldehydes has attracted much attention in recent *** the process ofα,β-unsaturated aldehyde hydrogenation,a conjugated system is formed between>C=CC=O,leading to hydrogenation at both ends of the conjugated system,which competes with each other and results in more complex ***,improving the reaction selectivity is also difficult in industrial ***,many researchers have reported that surface-active sites on catalysts play a crucial role inα,β-unsaturated aldehyde *** review attempts to summarize recent advances in understanding the effects of surface-active sites(SASs)over metal catalysts for enhancing the process of *** construction strategies and roles of SASs for hydrogenation catalysts are *** attention has been given to the adsorption configuration and transformation mechanism ofα,β-unsaturated aldehydes on catalysts,which contributes to understanding the relationship between SASs and hydrogenation *** addition,recent advances in metal-supported catalysts for the selective hydrogenation ofα,β-unsaturated aldehydes to understand the role of SASs in hydrogenation are briefly ***,the opportunities and challenges will be highlighted for the future development of the precise construction of SASs.

关键词： α,β-unsaturatedd aldehydes hydrogenation active site cinnamaldehyde

A Comprehensive Review on Mechanisms and Applications of Rare-Earth Based Perovskite Nanocrystals

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Chinese Journal of Chemistry 2024年第9期42卷 1032-1056页

作者： Xiaoshan Zhang Yikun Wang Xiang Wu Feilong Wang Qiongrong Ou Shuyu Zhang Academy for Engineering and technology Institute of Future LightingFudan UniversityShanghai 200433China School of Information Science and technology Institute for Electric Light SourcesFudan UniversityShanghai 200433China

Rare earth(RE)ions,with abundant 4f energy level and unique electronic arrangement,are considered as substitutes for Pb^(2+)in perovskite nanocrystals(PNCs),allowing for partial or complete replacement of lead and minimizing environmental *** review provides a comprehensive overview of the characteristics of RE-doped PNCs,including up-conversion luminescence,down-conversion luminescence,and quantum confinement effects,***,RE doping has been found to effectively suppress defect formation,reduce nonradiative recombination,enhance photoluminescence quantum yield(PLQY),and even allow for controlling over the morphology of the *** review also highlights the recent advancements in lead-free RE-based perovskites,especially in the case of Eu-based perovskites(CsEuBr_(3) and CsEuCl_(3)).Furthermore,it briefly introduces the applications of PNCs in various fields,such as perovskite solar cells(PSCs),luminescent solar concentrators(LSCs),photodetectors(PDs),and light-emitting diodes(LEDs).A systematic discussion on the luminescence mechanisms of RE-doped PNCs and lead-free RE-based perovskites is provided,along with an outlook on future research *** ultimate goal of this review is to provide guidance for the development of RE-based perovskite optoelectronic devices.

关键词： Perovskite nanocrystals Rare earth Lead-free perovskite lon doping Rare earth-based perovskite nanocrystals

A highly sensitive LITES sensor based on a multi-pass cell with dense spot pattern and a novel quartz tuning fork with low frequency

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Opto-Electronic Advances 2024年第3期7卷 26-34页

作者： Yahui Liu Shunda Qiao Chao Fang Ying He Haiyue Sun Jian Liu Yufei Ma National Key Laboratory of Science and technology on Tunable Laser Harbin Institute of TechnologyHarbin 150000China Zhengzhou research institute Harbin Institute of TechnologyZhengzhou 450000China Advanced Microscopy and Instrumentation research Center School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China.

A highly sensitive light-induced thermoelectric spectroscopy(LITES)sensor based on a multi-pass cell(MPC)with dense spot pattern and a novel quartz tuning fork(QTF)with low resonance frequency is reported in this *** erbi-um-doped fiber amplifier(EDFA)was employed to amplify the output optical power so that the signal level was further *** optical path length(OPL)and the ratio of optical path length to volume(RLV)of the MPC is 37.7 m and 13.8 cm^(-2),respectively.A commercial QTF and a self-designed trapezoidal-tip QTF with low frequency of 9461.83 Hz were used as the detectors of the sensor,*** target gas selected to test the performance of the system was acetylene(C2H2).When the optical power was constant at 1000 mW,the minimum detection limit(MDL)of the C2H2-LITES sensor can be achieved 48.3 ppb when using the commercial QTF and 24.6 ppb when using the trapezoid-al-tip *** improvement of the detection performance by a factor of 1.96 was achieved after replacing the commer-cial QTF with the trapezoidal-tip QTF.

关键词： light-induced thermoelectric spectroscopy quartz tuning fork multi-pass cell gas sensing

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Tandem hydroformylation/hydrogenation of olefins to alcohols using atomically dispersed bifunctional catalysts

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Science China Chemistry 2024年第11期67卷 3706-3711页

作者： Ying Zhang Liyang Liu Ziyue Wang Xingcong Zhang Xiaohui He Hongbing Ji Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education Fine Chemical Industry Research InstituteSchool of Chemistry IGCME Sun Yat-sen University Guangdong technology research Center for Synthesis and Separation of Thermosensitive Chemicals State Key Laboratory Breeding Base of Green-Chemical Synthesis technology Institute of Green Petroleum Processing and Light Hydrocarbon Conversion College of Chemical Engineering Zhejiang University of Technology

Tandem hydroformylation/hydrogenation of olefins to alcohols is an appealing and challenging route that has received continuous interest. Herein, we report a bifunctional atomically dispersed Rh and Co catalyst（Rh Co/Al2O3-10） prepared by a simple ball milling method that displays superior synergistic catalytic performance（>95% olefins conversion and >80% alcohols selectivity） and broad substrate scope for tandem hydroformylation/hydrogenation reaction, outperforming Rh/Al2O3, Co/Al2O3,and their physically mixed counterparts. In situ CO-DRIFTS, XPS, and kinetic experiments demonstrate that the electron interaction between Rh and Co atoms effectively lowers the apparent activation energy, thus promoting the tandem hydroformylation/hydrogenation reaction. This work not only presents a novel tandem hydroformylation/hydrogenation reaction system for converting olefins to alcohol but also throws light on the rational design of versatile bifunctional catalysts for ondemand synergistic catalysis.

关键词： tandem hydroformylation/hydrogenation alcohols bifunctional single atom catalysts

Enhanced photoluminescence of a microporous quantum dot color conversion layer by inkjet printing

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Nano research 2024年第8期17卷 7717-7725页

作者： Junchi Chen Qihao Jin Yidenekachew.J.Donie Orlando.T.Perales Dmitry Busko Bryce.S.Richards Uli Lemmer light technology institute(LTI) Karlsruhe Institute of Technology(KIT)Engesserstrasse 1376131 KarlsruheGermany Department of Chemical Engineering and Materials Science University of Minnesota(UMN)421 Washington Ave.SEMinneapolisMN 55455-0132USA institute for Microstructure technology Karlsruhe Institute of Technology(KIT)Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany

Owing to their high color purity,tunable bandgap,and high efficiency,quantum dots(QDs)have gained significant attention as color conversion materials for high-end display ***,inkjet-printed QD pixels show great potential for realizing full-color mini/micro-light emitting diode(micro-LED)-based *** a color conversion layer,the photoluminescence intensity of QDs is limited by the insufficient absorptance of the excitation light due to the lack of *** scatterers,such as titanium dioxide microparticles,have been applied after additional surface engineering for sufficient dispersity to prevent nozzle clogging in inkjet printing *** our work,as an alternative approach,we use inkjet printing for depositing a phase separating polymer ink based on polystyrene(PS)and polyethylene glycol(PEG).QD/polymer composite pixels with scattering micropores are *** morphology of the micropores can be tailored by the weight ratio between PS and PEG which enables the manipulation of scattering *** the presence of the microporous structure,the photoluminescence intensity of the QD film is enhanced by 110%in drop-cast films and by 35.3%in inkjet-printed QD pixel arrays compared to the reference samples.

关键词： porous structure inkjet printing phase separation quantum dots display technology

Preheating-assisted solid-state friction stir repair of Al-Mg-Si alloy plate at different rotational speeds

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 725-736页

作者： Hui Wang Yidi Li Ming Zhang Wei Gong Ruilin Lai Yunping Li State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China research institute of light Alloy Central South UniversityChangsha 410083China

Additive friction stir deposition(AFSD)is a novel structural repair and manufacturing technology has become a research hotspot at home and abroad in the past five *** this work,the microstructural evolution and mechanical performance of the Al-Mg-Si alloy plate repaired by the preheating-assisted AFSD process were *** evaluate the tool rotation speed and substrate preheating for repair quality,the AFSD technique was used to additively repair 5 mm depth blind holes on 6061 aluminum alloy *** results showed that preheat-assisted AFSD repair significantly improved joint bonding and joint strength compared to the control non-preheat substrate ***,increasing rotation speed was also beneficial to improve the metallurgical bonding of the interface and avoid volume *** preheating conditions,the UTS and elongation were positively correlated with rotation *** the process parameters of preheated substrate and tool rotation speed of 1000 r/min,defect-free specimens could be obtained accompanied by tensile fracture occurring in the substrate rather than the repaired *** UTS and elongation reached the maximum values of 164.2MPa and 13.4%,which are equivalent to 99.4%and 140%of the heated substrate,respectively.

关键词： additive friction stir deposition structural repair tool rotation speed Al alloy

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All-inorganic ultrathin high-sensitivity transparent temperature sensor based on a Mn-Co-Ni-O nanofilm

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Microsystems & Nanoengineering 2024年第3期10卷 195-205页

作者： Yuanyuan Cui Mengwei Sun Changbo Liu Yuan Deng research institute for Frontier Science Beihang UniversityBeijing 100191China School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Intelligent sensing Materials and Chip Integration technology of Zhejiang Province Hangzhou Innovation Institute of Beihang UniversityHangzhou 310051China

The demand for optically transparent temperature sensors in intelligent devices is ***,the performance of these sensors,particularly in terms of their sensitivity and resolution,must be further *** study introduces a novel transparent and highly sensitive temperature sensor characterized by its ultrathin,freestanding design based on a Mn-Co-Ni-O *** Mn-Co-Ni-O-based sensor exhibits remarkable sensitivity,with a temperature coefficient of resistance of−4%℃^(−1),and can detect minuscule temperature fluctuations as small as 0.03℃.Additionally,the freestanding sensor can be transferred onto any substrate for versatile application while maintaining robust structural stability and excellent resistance to interference,indicating its suitability for operation in challenging *** practical utility in monitoring the surface temperature of optical devices is demonstrated through vertical integration of the sensor and a micro light-emitting diode on a polyimide ***,an experiment in which the sensor is implanted in rats confirms its favorable biocompatibility,highlighting the promising applications of the sensor in the biomedical domain.

关键词： transparent sensor versatile