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Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao zheng Zi-An Zhou Tiao Feng Hui Li Cheng-Hua Sun nüWang Yang Tian Yong Zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

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Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope

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Research in Astronomy and Astrophysics 2024年第1期24卷 135-150页

作者： Weirui Chen zheng Wang School of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast UniversityNanjing 210096China

Leighton Chajnantor Telescope(LCT), i.e., the former Caltech Submillimeter Observatory telescope, will be refurbished at the new site in Chajnantor Plateau, Chile in 2023. The environment of LCT will change significantly after its relocation, and the telescope will be exposed to large wind disturbances directly because its enclosure will be completely open during observation. The wind disturbance is expected to be a challenge for LCT's pointing control since the existing control method cannot reject this disturbance very well. Therefore, it is very necessary to develop a new pointing control method with good capability of disturbance rejection. In this research, a disturbance observer—based composite position controller(DOB-CPC) is designed, in which an H∞feedback controller is employed to compress the disturbance, and a feedforward linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller switching policy is adopted, which applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. numerical experiments are conducted to verify the good performance of the proposed pointing controller(i.e., DOB-CPC) for rejecting the disturbance acting on LCT.

关键词： instrumentation:miscellaneous methods:analytical methods:numerical telescopes

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Sustainable ammonia synthesis:An in-depth review of non-thermal plasma technologies

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Journal of Energy Chemistry 2024年第9期96卷 1-38页

作者： Vahid Shahed Gharahshiran Ying zheng Department of Chemical and Biochemical Engineering Thompson Engineering BuildingWestern UniversityLondonON N6A 5B9Canada

Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free ***,it offers convenient transportation and storage as a hydrogen *** dominant method used for large-scale ammonia production is the Haber-Bosch process,which requires high temperatures and pressures and is ***,non-thermal plasma offers an eco-friendly alternative for ammonia synthesis,gaining significant *** enables ammonia production at lower temperatures and pressures using plasma *** review provides insights into the catalyst and reactor developments,which are pivotal for promoting ammonia efficiency and addressing existing *** first,the reaction kinetics and mechanisms are introduced to gain a comprehensive understanding of the reaction pathways involved in plasma-assisted ammonia ***,the enhancement of ammonia synthesis efficiency is discussed by developing and optimizing plasma reactors and effective *** effect of other feeding sources,such as water and methane,instead of hydrogen is also ***,the challenges and possible solutions are outlined to facilitate energy-saving and enhance ammonia efficiency in the future.

关键词： nitrogen fixation Ammonia synthesis nH_(3) non-thermal plasma ni Ru catalyst

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A Fibonacci View on the Galois nFSR Used in Trivium

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Journal of Systems Science & Complexity 2024年第3期37卷 1326-1350页

作者： WAnG Hongyu zheng Qunxiong QI Wenfeng PLA Strategic Support Force Information Engineering University Zhengzhou 450001China

Trivium is an international standard of lightweight stream ciphers(ISO/IEC 29192-3:2012).In this paper,the Trivium-like nFSRs,a class of Galois nFSRs generalized from the Galois nFSR of Trivium,are studied from the perspective of Fibonacci *** is shown that an n-stage Trivium-like nFSR cannot be equivalent to an n-stage Fibonacci nFSR,which is proved by showing the existence of“collision initial states”.As an intermediate conclusion,a necessary and sufficient condition for a kind of linear degeneracy of a Trivium-like nFSR is obtained from the persepective of interleaved ***,the smallest stage number of a Fibonacci nFSR that can generate all the output sequences of an n-stage Trivium-like nFSR is shown to be greater than n-7 and this value is no less than 371=287+min{93,84,111}specifically for the 288-stage Galois nFSR used in *** results contradict the existence of a equivalent Fibonacci model of Trivium nFSR of small stage,which implies that Trivium algorithm possesses a fair degree of immunity against“structure attack”.

关键词： Fibonacci nFSR galois nFSR interleaved sequence linear degeneracy trivium

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Greedy Lattice Paths with General Weights

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2213-2222页

作者： Yin Shan CHAnG An Qi zheng College of Mathematics Sichuan UniversityChengdu 610065P.R.China

Let{X_(v):v∈Z^(d)}be *** *** S(π)=Σ_(v∈π)X_(v)be the weight of a self-avoiding lattice pathπ.Let M_(n)=max{S(π):πhas length n and starts from the origin}.We are interested in the asymptotics of Mn as n→∞.This model is closely related to the first passage percolation when the weights{X_(v):v∈Z^(d)}are non-positive and it is closely related to the last passage percolation when the weights{X_(v):v∈Z^(d)}are *** general weights,this model could be viewed as an interpolation between first passage models and last passage ***,this model is also closely related to a variant of the position of right-most particles of branching random *** the two assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)nd that E[X_(0)^(−)]nite real number M such that Mn/n converges to a deterministic constant M in L^(1)as n tends to *** under the stronger assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)nd that E[(X_(0)^(−))^(4)]n)/n converges to the same constant M almost surely as n tends to infinity.

关键词： Last passage percolation first passage percolation greedy lattice path

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Body size induced changes in metabolic carbon of soil nematodes under n deposition and precipitation regime change in a temperate grassland

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Ecological Processes 2024年第1期13卷 120-131页

作者： Shuyan Cui Xiaomei Mo Guo zheng College of Life Science Shenyang Normal University

Background Global climate change has resulted in precipitation regimes exhibiting an increasing trend in rainfall intensity but a reduction in its frequency. nitrogen(n) deposition is a crucial component of the global n cycling. nematode body size is a trait that responds to climate change and is used as a standard trait-based indicator in soil community analysis. Variations in body size influence metabolic carbon(C). We examined the ways by which body size and metabolic C of nematodes respond to changing precipitation regimes and how n deposition regulates these responses by an 8-year manipulative *** nematode body size was indicated by the community-weighted mean(CWM) mass. We quantified C metabolism components of soil nematodes including production C, respiration C, and corresponding C use efficiency(CUE) under different precipitation intensities and n addition in a semi-arid steppe on the Mongolian Plateau. The Mantel test was used to determine the correlations between CWM, CUE and environmental factors. The partial least squares path modeling(PLS-PM) was conducted to quantify direct or indirect contributions among latent *** We found that heavy precipitation intensity increased the CWM mass of total nematodes and omnivorespredators without n addition. n addition decreased CWM mass of bacterivores across all the precipitation intensity treatments. Stronger precipitation intensities might be favorable for nematode production and respiration C. Variations in the nematode CWM mass drove the CUE to change with n *** Our findings provide new insights into the mechanisms underlying nematode body size and C metabolism, and highlight that explorative studies, such as manipulative experiments, are needed to identify traits underlying size-related effects and to investigate how they affect CUE of nematodes. These efforts may increase our understanding of how changes in precipitation regimes and n deposition may alter soil nema

关键词： Community-weighted mean Metabolic footprint nitrogen addition Precipitation intensity

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Appreciable Enhancement of Photocatalytic Performance for n-doped SrMoO_(4) via the Vapor-thermal Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 24-31页

作者：恽志强戴振翔 ZHU liwei zheng Ganhong School and Materials Science and Engineering Anhui UniversityHefei 230601China School of Physics and Optoelectronics Engineering Anhui UniversityHefei 230601China

A series of nitrogen-doped SrMoO_(4) with different Sr/n mole ratio (R=0,0.05,0.10,0.15,0.20,0.40,and 0.60) were synthesized using urea as the n source via the vapor-thermal *** photocatalytic degradation ability of all samples was evaluated using methylene blue (MB) as a target *** band gaps of n-doped samples are all higher than that of pristine ones,which is only 3.12 *** specific surface area S_(BET) and pore volume are increased due to the n *** the greater increase of S_(BET),the faster the photodegradation speed of methylene blue on SrMoO_(4).More specifically,the degradation efficiency of MB is improved up to 87%in 100 min.

关键词： SrMoO_(4) photocatalytic property nitrogen element doping

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π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao Dong-Chun zheng Pin-Xi Ou Qi-Xin Zhao Wei-Min Xuan Qi zheng State Key Laboratory for Modification of Chemical Fibers and Polymer Materials&College of Materials Science and Engineering Donghua UniversityShanghai201620China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials and College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China

n-doping has significant influence in manipulating the properties of TiO_(2),and this has stimulated the development of n-donor-functionalized titanium-oxo clusters(TOCs)as molecular models to study the structure-property ***,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO_(2)for ***,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds usingπ-conjugated 1,10-phenanthroline(phen)as chromophore and n-donor functional *** 1 features cocrystal structure composed of one[Ti_(26)]~(2+)and half[Ti_(22)]~(2+),which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti *** adjusting the synthetic conditions,the individual{Ti_(22)}and{Ti_(26)}clusters can also be isolated as Compounds 2 and 3,*** core structure of{Ti_(22)}is mainly constructed from four lacunary{Ti_(4)}derived from pentagonal{Ti(Ti)_5}unit,while{Ti_(26)}is built from four complete{Ti(Ti)_5}***,a{Ti_8O_(14)}structure unit of anatase TiO_(2)can be identified in{Ti_(26)}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic *** to the presence of anatase structure unit in{Ti_(26)}and the synergistic effect from{Ti_(22)}and{Ti_(26)},the catalytic performance presents in the order of Compound 1>Compound 3>Compound *** work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO_(2) High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

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Selective n-Methylation of n-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： Huan zheng Bo Qian Lin He State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

n-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because n-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for n-methylation reaction of n-methylaniline (MA) with CO_(2) and H_(2),showing higher n,n-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate n-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—n bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： n-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts Heterogeneous catalysis

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Plasma spray coating on interconnector toward promoted solid oxide fuel cells and solid oxide electrolysis cells

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Frontiers in Energy 2024年第3期18卷 390-398页

作者： Junwen CAO Yun zheng Wenqiang ZHAnG Bo YU Institute of nuclear and new Energy Technology(InET) Collaborative Innovation Center of Advanced Nuclear Energy TechnologyTsinghua UniversityBeijing 100084China Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1Canada Institute of new Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

Interconnector is a critical component to construct solid oxide cells (SOCs) stack. Oxidation of metallic interconnectors and Cr poisoning caused by oxidation are important factors that lead to long-term performance degradation of SOCs. Coating on the interconnector surface is an important approach to inhibit the oxidation and Cr migration of the interconnector. Herein, (La0.75Sr0.25)0.95MnO3–δ (LSM) and Mn1.5Co1.5O4 (MCO) are used to fabricate the coatings of interconnector. Two advanced thermal spray technology, atmospheric plasma spraying (APS) and low-pressure plasma spray (LPPS), are adopted for the coating preparation. The electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition performance of the coatings are tested and evaluated. The result indicates that MCO can generate more uniform and denser coatings than LSM. In addition, MCO coatings prepared by LPPS shows the best electrochemical performance, rising and cooling cycle stability, and Cr diffusion inhibition. The initial area specific resistance (ASR) is 0.0027 Ω·cm2 at 800 °C. After 4 cooling cycle tests, the ASR increases to 0.0032 Ω·cm2 but lower than other samples. Meanwhile, the relative intense of Cr at the interface of SUS430 with MCO coatings fabricated by LPPS is lower than that of MCO fabricated by APS after 4 rising and cooling cycle operations, showing more favorable Cr diffusion inhibition performance.

关键词： interconnector coating plasma spray electrochemical performance Cr diffusion inhibition solid oxide cells(SOCs)

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