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High-resolution imaging through dynamic scattering media: Iterative optimization based on polarimetric characteristics

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Science China Technological Sciences 2025年第1期 82-84页

作者： Meng xiang Kai DENG Tianyu WANG Jinpeng LIU Xue DONG Teli XI fei LIU Xiaopeng shaO School of Optoelectronic Engineering Xidian University Xi'an Key Laboratory of Computational Imaging National Key Laboratory of Infrared Detection Technologies

High-resolution imaging through randomly dynamic scattered fields and highly scattered walls is an extensively sought-after capability with potential applications in various fields such as underwater imaging, biomedical imaging, and seeing through fog. Numerous methods have been proposed to unscramble object information from degraded scattered images, resulting in considerable improvements in image contrast in degraded scenarios [1].

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Conformally anchoring nanocatalyst onto quartz fibers enables versatile microreactor platforms for continuous-flow catalysis

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Science China Chemistry 2021年第9期64卷 1596-1604页

作者： Jiahui Fan Jian Lu Zhou sha Weiwei Zuo xiang fei Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China

Continuous-flow microreactors offer increased reactivity and reusability via unique reaction pathways to address a wide range of practical nanocatalysis ***,only limited platforms exist to employ these microreactors for versatile nanocatalytic *** this work,we conformally anchored nickel oxide(Ni O)nanosheets onto quartz fibers(QFs),which exhibited a high catalytic activity using the hydrogenation of 4-nitrophenol(4-NP)as a model reaction in a batch reaction *** importantly,we demonstrated that fiber-based QF@Ni O composites(e.g.,cotton,fabric,belt,felt)can be integrated as versatile platforms to develop microreactors for continuous-flow catalytic applications including hydrogenation reactions and dyecatalyzed *** fiber-based three-dimensional(3 D)nanocatalyst architecture effectively drives continuous-flow catalytic reactions with unprecedented efficiency due to the easy diffusion of reactant molecules into the fibrous structure,allowing contact with catalytic active *** approach to continuous-flow microreactor design uses surface hybridization as a guideline to immobilize nanocatalysts onto the *** QF-based platforms,coupled with rational design,are expected to be applied to a wide range of nanocatalytic reactions.

关键词： quartz fiber platform nanocatalyst immobilization microreactor continuous-flow catalysis

Effect of Ce addition on hot corrosion behaviours of a cast γ'-strengthened Co–Al–W–Mo–Ta–B alloy at 800 ℃

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Progress in Natural Science:Materials International 2022年第4期32卷 463-471页

作者： Qi Guan fei Zhong Jiangbo sha School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Key Laboratory of Aerospace Materials and Performance (Ministry of Education) College of Chemistry and Materials Science Hubei Engineering University

Hot corrosion behaviours of a novel Co–9Al-4.5W-4.5Mo–2Ta-0.02B alloy doped with 0.01, 0.05, 0.1 and 0.2 at%Ce exposed at 800℃ in a solution of 75%Na2SO4/25%Na Cl were investigated. The alloys comprised a coherentγ-CoSS/γ’-Co3(Al, W) microstructure(0.01Ce and 0.05Ce alloys) and κ-Co3(W, Mo) precipitates(0.1Ce and 0.2Ce alloys) at grain boundaries. Hot corrosion kinetics curves demonstrated the parabolic time dependency profile with two stages: the first parabolic stage is within the beginning ～50 h corrosion and follows by the second parabolic stage. With an increasing nominal Ce content the weight gain of the alloy significantly decreased from approximately 70.1 mg cm-2(0.01Ce) to 40.8 mg cm-2(0.2Ce) when exposed for 100 h. A two-layer corrosion scale formed, and the scale was composed of an outer layer of Co3O4oxide with spinel compounds of Co Al2O4,CoWO4and CoSO4, and an inner γ/needle-like Co3W/sulphide layer adhered to the substrate. Heavy spallation of the corrosion scale occurred in the 0.01Ce～0.1Ce alloys, however, spallation was slight in the 0.2Ce alloy. The excellent corrosion resistance of the 0.2Ce alloy could be attributed mainly to the formation of continuous Al2O3lines in the corrosion scale, as well as the prolongation of the incubation period of the corrosion product spallation.

关键词： Co–Al–W-Based alloys Doping Ce Microstructural evolution Kinetics curves Hot corrosion mechanisms

High-temperature oxidation behaviour of novel Co-Al-W-Ta-B-(Mo,Hf,Nb) alloys with a coherent γ/γ'–dominant microstructure

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Progress in Natural Science:Materials International 2016年第6期26卷 600-612页

作者： fei Zhong fei Fan Shusuo Li Jiangbo sha School of Materials Science and Engineering Beihang University

In this work,2at% Mo,2at% Nb and 2at% Hf were substituted for the same amount of W into a Co-9Al-9W-2Ta-0.02 B alloy（hereafter referred as to 2Mo, 2Nb and 2Hf alloys, respectively, while the original alloy is denoted as 0Me alloy）. The effect of the Mo, Hf and Nb additions on the isothermal oxidation resistance, oxide scale evolution and failure mechanism, of the Co-9Al-9W-2Ta-0.02 B alloy when exposed at 800 °C and 900 °C for 100 h was investigated. It was found the Mo, Hf and Nb additions degraded the oxidation resistance of the Co-9Al-9W-2Ta-0.02 B alloy, while the 2Mo alloy always displayed the poorest oxidation resistance, resulted from heavy spallation of the oxide scale. An oxide scale composed of an outer Co3O4+CoO layer, a middle complex oxide layer enriched with Al, W and Ta, and a γ/needle-like Co3W zone adhering to the γ/γ' substrate was gradually formed; moreover, a continuous or discontinuous Al2O3layer and dispersive Al2O3dots or slices were observed within the γ/needle-like Co3W zone, depending on the oxidation temperature and added elements（Mo, Hf and Nb）. The formation of volatile MoO3in the oxide scale of the 2Mo alloy enhance the exfoliation of the oxide products, resulting in severe spallation and poor oxidation resistance.

关键词： Co-Al-W based superalloys Mo,Nb,Hf alloying Oxidation behaviour Oxide scale spallation

Alternative non-Gaussianity measures for quantum states based on quantum fidelity

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Chinese Physics B 2022年第3期31卷 192-200页

作者： Cheng xiang shan-shan Li sha-sha Wen shao-Hua xiang College of Electrical and Information Engineering Huaihua UniversityHuaihua 418008 China Hunan Provincial Key Laboratory of Ecological Agriculture Intelligent Control Technology Huaihua 418008China

We propose three alternative measures for non-Gaussianity of quantum states: sine distance, Bures angle, and Bures distance, which are based on quantum fidelity introduced by Wang [Phys. Lett. A 373 58(2008)]. Using them, we evaluate the non-Gaussianity of some relevant single-mode and two-mode non-Gaussian states and find a good consistency of the three examined measures. In addition, we show that such metrics can exactly quantify the degree of Gaussianity of even Schrödinger-cat-like states of small amplitudes that can not be measured by other known non-Gaussianity measures such as the Hilbert–Schmidt metric and the relative entropy metric. We make a comparative study between all existing nonGaussianity measures according to the metric axioms and point out that the sine distance is the best candidate among them.

关键词： non-Gaussianity quantum fidelity non-Gaussian states sine metric

Improvement of isothermal oxidation resistance of aγ'-strengthened Co-Al-W-Mo-Ta-B alloy at 800℃via doping Ce

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Rare Metals 2021年第8期40卷 2065-2075页

作者： fei Zhong Zhuo-Lin Tao Jiang-Bo sha School of Materials Science and Engineering Beihang UniversityBeijing100191China College of Chemistry and Materials Science Hubei Engineering UniversityXiaogan432000China

Isothermal oxidation resistance,oxide scale evolution and failure mechanism of Ce-doped Co-Al-W-MoTa-B alloy(0.01 at%,0.05 at%,0.10 at%and 0.20 at%Ce)exposed at 800℃were *** 0.01 Ce and 0.05 Ce alloys were consisted ofγ/γ’coherent micro structure,while theκ-Co_(3)W compound precipitated at the grain boundary of the 0.1 OCe and 0.20 Ce alloys in addition to theγ/γ’*** oxidation kinetics curves of the Cedoped alloys exhibited a parabolic time dependence on the weight *** an increasing nominal Ce content,the weight gain of the Co-Al-W-Mo-Ta-B alloys monotonically *** oxide scale composed of a dense and uniform outer Co_(3)O_(4)+CoO layer,a middle CoAl2 O4 and CoWO4 compound layer and an inner Al_(2)O_(3)*** excellent oxidation resistance of 0.2 Ce alloy was mainly attributed to a shorter incubation stage for the formation of the continuous and protective Al_(2)O_(3)layer and the thickest Al_(2)O_(3)layer during entire oxidation process.

关键词： Co-Al alloy Intermetallics Ce doping Oxidation

Enzyme Activities in Perfluorooctanoic Acid (PFOA)-Polluted Soils

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Pedosphere 2013年第1期23卷 120-127页

作者： ZHANG Wei LIN Kuang-fei YANG sha-sha ZHANG Meng School of Resource and Environmental Engineering East China University of Science and Technology State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process shanghai Key Laboratory of Functional Materials Chemistry East China University of Science and Technology

Perfluorooctanoic acid （PFOA） is a popular additive of the chemical industry; its effect on activities of important soil enzymes is not well understood. A laboratory incubation experiment was carried out to analyze the PFOA-induced changes in soil urease, catalase, and phosphatase activities. During the entire incubation period, the activities of the three soil enzymes generally declined with increasing PFOA concentration, following certain dose-response relationships. The values of EC10, the contaminant concentration at which the biological activity is inhibited by 10%, of PFOA for the soil enzyme activity calculated from the modeling equation of the respective dose-response curve suggested a sensitivity order of phosphatase 〉 catalase 〉 urease. The effect of PFOA on soil enzyme activities provided a basic understanding of the eco-toxicological effect of PFOA in the environment. Results of this study supported using soil ohosohatase as a convenient biomaxker for ecological risk assessment of PFOA-oolluted soils.

关键词： activity inhibition biomarker dose-response curve ecological risk regression equation

Photoluminescence properties of hexagonal indium tin oxide nanopowders prepared by solvothermal method

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Rare Metals 2018年第1期37卷 47-53页

作者： fei Liang Jia-xiang Liu The State Key Laboratory of Chemical Resource Engineering The Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Hexagonal structure indium tin oxide（ITO）nanopowders were prepared by a solvothermal process at only 175 ℃ for 24 h and post-annealing at 400 ℃, using metal indium and SnCl4·5 H2 O as the raw materials. The morphology, crystal structures and structure defects of products were, respectively, analyzed by scanning electron microscopy（SEM）, X-ray diffraction（XRD） and confocal microprobe Raman system, the elemental state was investigated by X-ray photoelectron spectroscopy（XPS）, and the optical properties were carried out by ultraviolet-visible（UV-Vis） and photoluminescence（PL） spectrophotometers. The results show that the products are hexagonal structure with a particles size of 28-41 nm; the morphology of products consists of sphere and irregular *** pH values of solution increase, the content of oxygen vacancies increases and the optical band gap varies from3.59 to 3.78 eV. The products exhibit strong emission at417 nm with an excitation of 370 nm, and the PL intensity of samples increases with pH values increasing. Contrasting to cubic structure ITO powder, the hexagonal structure ITO has narrower optical band gap and higher PL intensity under the same excitation wavelength.

关键词： Hexagonal indium tin oxide Solvothermal Oxygen vacancies Optical band gap Photoluminescence

Frequency Loss and Recovery in Rolling Bearing Fault Detection

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 145-156页

作者： Aijun Hu Ling xiang sha Xu Jianfeng Lin Department of Mechanical Engineering North China Electric Power University

Rolling element bearings are key components of mechanical equipment. The bearing fault characteristics are a ected by the interaction in the vibration signals. The low harmonics of the bearing characteristic frequencies cannot be usually observed in the Fourier spectrum. The frequency loss in the bearing vibration signal is presented through two independent experiments in this paper. The existence of frequency loss phenomenon in the low frequencies, side band frequencies and resonant frequencies and revealed. It is demonstrated that the lost frequencies are actually suppressed by the internal action in the bearing fault signal rather than the external interference. The amplitude and distribution of the spectrum are changed due to the interaction of the bearing fault signal. The interaction mechanism of bearing fault signal is revealed through theoretical and practical analysis. Based on mathematical morphology, a new method is provided to recover the lost frequencies. The multi-resonant response signal of the defective bearing are decomposed into low frequency and high frequency response, and the lost frequencies are recovered by the combination morphological filter(CMF). The e ectiveness of the proposed method is validated on simulated and experimental data.

关键词： Rolling element bearing Signal processing Frequency loss Fault detection Morphological filter