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可变冷光阑红外探测器研究进展和关键技术分析

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红外技术 2024年第4期46卷 376-383页

作者：孙鸿生陈晓屏夏明陈军黄一彬甘游宇李淑芬昆明物理研究所云南昆明650223

为了进一步提高红外变焦光学系统的性能,兼顾其空间分辨率和灵敏度的要求,基于可变冷光阑技术的制冷型变F数红外探测器需求迫切。相较于传统的红外变焦光学系统,变F数红外变焦光学系统可在大视场和小视场切换时保持分辨率和灵敏度的平衡... 详细信息

为了进一步提高红外变焦光学系统的性能,兼顾其空间分辨率和灵敏度的要求,基于可变冷光阑技术的制冷型变F数红外探测器需求迫切。相较于传统的红外变焦光学系统,变F数红外变焦光学系统可在大视场和小视场切换时保持分辨率和灵敏度的平衡,提高光学系统的孔径利用率,进而缩小光学系统的径向尺寸,有利于红外光学系统成像质量的提升和小型化设计。本文对变F数与变焦之间的关系进行研究,概述了国内外在可变冷光阑红外探测器技术领域的研究进展,并对主流技术路线的关键技术难点进行了分析。

关键词：红外探测器可变冷光阑变F数变焦

A new method to measure the concentration of argon-xenon gas mixture

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Radiation Detection Technology and Methods 2021年第2期5卷 280-283页

作者： Jiajun Li Mengyun Guan youyu gan Peng Zhang Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China North China Electric Power University Beijing 100096China

RGAs are widely used in molec Background RGAs are widely used in molecular component examination,impurity analysis,leak detection and test of vacuum system ***,RGAs have different sensitivities to different gases,and the sensitivities can change quickly and depend on so many parameters,which make its ability severely *** In thiswork we established a newpractical method to precisely measure noble gas ratio of argon-xenon *** argon and xenon were controlled,respectively,by two mass flow controller(MFC).A variable leak valve(VLV)was used to introduce the gas mixture sample into the RGA measurement *** mixtures with xenon concentration from 200ppm to 20000ppm(by mass)were introduced and tested by *** The time stability of RGA-measurement system was optimized to 2.1%.A good linearity of MFC-RGA response was achieved,verifying the reliability of RGA in measuring noble gas mixture with component concentration down to several hundred ppm *** Since the approach we used in our experiment is gas-species independent,we believe that it can be popularized to other gas species when properly applied.

关键词： Residual gas analyzers Gas mixture Variable leak valve Noble gas

Atomically dispersed materials:Ideal catalysts in atomic era

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Nano Research 2024年第1期17卷 18-38页

作者： Tao gan Dingsheng Wang Department of Chemistry Tsinghua UniversityBeijing 100084China

Catalysts can accelerate the chemical reaction rate and effectively promote the molecules transformation,which is of great significance in the research of chemical industry and material *** extreme utilization of reactive sites has led to the emergence and development of atomically dispersed materials(ADMs).The highly active coordination unsaturated metal sites and fully utilized metal atoms make ADMs show great potential in catalytic *** adjustment of coordination environment and electronic structure provides more possibilities for constructing reactive centers with different *** review summarized the application and research progress of ADMs in different *** design strategy and structure–activity relationship of ADMs for specific reactions were summarized and ***,we also provided advices for the challenges and opportunities faced by ADMs in catalytic reactions.

关键词： atomically dispersed materials catalysis organic synthesis battery sensor enzyme

Progress Report on ASO-S: 2022–2024

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空间科学学报 2024年第4期44卷 687-689页

作者： gan Weiqun Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023

The Advanced Space-based Solar Observatory(ASO-S)marked China's first comprehensive solar mission in *** upon the previous reports covering 2018-2020 and 2020-2022,we present here an update on the ASO-S made from 2022 to *** August 2022,ASO-S completed its Phase D study and was successfully launched on October 9,*** commissioning phase was carried out and concluded within the first nine months following the *** data and associated analysis software have been opened to the community and the research on the early ASO-S data has been well *** anticipate also the achievements in data research pertaining to ASO-S in the near future.

关键词： Space astronomy Solar physics Spacecraft

Distributed Least Squares Algorithm of Continuous-Time Stochastic Regression Model Based on Sampled Data

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Journal of Systems Science & Complexity 2024年第2期37卷 609-628页

作者： ZHU Xinghua gan Die LIU Zhixin The Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciencesand School of Mathematical SciencesUniversity of Chinese Academy of SciencesBeijing 100190China Zhongguancun Laboratory Beijing 100094China

In this paper,the authors consider the distributed adaptive identification problem over sensor networks using sampled data,where the dynamics of each sensor is described by a stochastic differential *** minimizing a local objective function at sampling time instants,the authors propose an online distributed least squares algorithm based on sampled data.A cooperative non-persistent excitation condition is introduced,under which the convergence results of the proposed algorithm are established by properly choosing the sampling time *** upper bound on the accumulative regret of the adaptive predictor can also be ***,the authors demonstrate the cooperative effect of multiple sensors in the estimation of unknown parameters by computer simulations.

关键词： Cooperative excitation condition distributed least squares regret sampled data stochastic differential equation

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： Yi Zhang Hui Cai Xiuhai gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

A Sustainable Dual Cross‑Linked Cellulose Hydrogel Electrolyte for High‑Performance Zinc‑Metal Batteries

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Nano-Micro Letters 2024年第6期16卷 63-75页

作者： Haodong Zhang Xiaotang gan Yuyang Yan Jinping Zhou Hubei Engineering Center of Natural Polymers‑Based Medical Materials Key Laboratory of Biomedical Polymers of Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072People’s Republic of China Zhongnan Hospital of Wuhan University Institute of Hepatobiliary Diseases of Wuhan UniversityTransplant Center of Wuhan UniversityWuhan 430072People’s Republic of China

Aqueous rechargeable Zn-metal batteries(ARZBs)are considered one of the most promising candidates for grid-scale energy ***,their widespread commercial application is largely plagued by three major challenges:The uncontrollable Zn dendrites,notorious parasitic side reactions,and sluggish Zn^(2+) ion *** address these issues,we design a sustainable dual crosslinked cellulose hydrogel electrolyte,which has excellent mechanical strength to inhibit dendrite formation,high Zn^(2+) ions binding capacity to suppress side reaction,and abundant porous structure to facilitate Zn^(2+) ions ***,the Zn||Zn cell with the hydrogel electrolyte can cycle stably for more than 400 h under a high current density of 10 mA cm^(−2).Moreover,the hydrogel electrolyte also enables the Zn||polyaniline cell to achieve high-rate and long-term cycling performance(>2000 cycles at 2000 mA g^(−1)).Remarkably,the hydrogel electrolyte is easily accessible and biodegradable,making the ARZBs attractive in terms of scalability and sustainability.

关键词： Cellulose Dual cross-linked Aqueous rechargeable Zn-metal batteries Hydrogel electrolyte

Blast waveform tailoring using controlled venting in blast simulators and shock tubes

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Defence Technology（防务技术） 2024年第7期37卷 14-26页

作者： Edward Chern Jinn gan Alex Remennikov David Ritzel Faculty of Engineering and Information Sciences University of WollongongWollongongNSW2522Australia Dyn-FX Consulting Ltd 19 Laird Ave NorthAmherstburgONN9V 2T5Canada

A critical challenge of any blast simulation facility is in producing the widest possible pressure-impulse range for matching against equivalent high-explosive *** tubes and blast simulators are often constrained with the lack of effective ways to control blast wave profiles and as a result have a limited performance *** wave shaping techniques employed in some facilities are reviewed but often necessitate extensive geometric modifications,inadvertently cause flow anomalies,and/or are only applicable under very specific *** paper investigates controlled venting as an expedient way for waveforms to be tuned without requiring extensive modifications to the driver or existing geometry and could be widely applied by existing and future blast simulation and shock tube *** use of controlled venting is demonstrated experimentally using the Advanced Blast Simulator(shock tube)at the Australian National Facility of Physical Blast Simulation and via numerical flow simulations with Computational Fluid *** venting is determined as an effective method for mitigating the impact of re-reflected waves within the blast *** control method also allows for the adjustment of parameters such as tuning the peak overpressure,the positive phase duration,and modifying the magnitude of the negative phase and the secondary shock of the blast *** paper is concluded with an illustration of the potential expanded performance range of the Australian blast simulation facility when controlled venting for blast waveform tailoring as presented in this paper is applied.

关键词： Advanced blast simulator Shock wave propagation Far-field explosion Blast loads Blast waves Computational fluid dynamics

Production of linear alkylbenzene over Ce containing Beta zeolites

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Chinese Journal of Chemical Engineering 2024年第3期67卷 220-227页

作者： Shiqi Zhang Shengzhi gan Baoyu Liu Jinxiang Dong School of Chemical Engineering and Light Industry Guangdong Provincial Key Laboratory of Plant Resources BiorefineryGuangzhou Key Laboratory of Clean Transportation Energy ChemistryGuangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na *** citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta ***,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid *** addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene.

关键词： Beta zeolites Catalysis Alkylation Long-chain olefins