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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 815-822页

作者： Jia-Ming Wang sheng-sheng qian Yuan-Yuan Liu Yang-Ting Sun Yi-Ming Jiang Jin Li Department of Materials Science Fudan University

The crevice corrosion behaviors of 436 stainless steels in chloride-containing solutions with sulfate addition were studied using potentiodynamic, galvanostatic and repassivation potential measurements. The results of these electrochemical tests were compared and discussed. Galvanostatic test was proved to be the most powerful technique in detecting the crevice corrosion of 436 stainless steels, while the repassivation potential measurement was the most time-saving method in this study. Sulfate ions have inhibited the crevice corrosion of 436 stainless steels in chloride-containing solution, which may result from the effects of competitive adsorption and the IR drop mechanism.

关键词： Crevice corrosion Ferritic stainless steels Electrochemical techniques Sulfate ions Competitive adsorption IR drop mechanism

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng Xu sheng Pang Liangwei Cong Guoyu qian Dong Wang Laishi Li Yusheng Wu Zhi Wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min Xing Hai-Dong qian Qiao Gao sheng-Lan Xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

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PTN的关键技术及优势

信息技术 2010年第12期34卷 202-205页

作者：圣钱生张桂英海军指挥学院浦口分院南京211800

介绍了一种新型分组传输网络PTN,全面介绍了PTN的关键技术,重点阐述了T-MPLS协议,最后对PTN的技术优势进行了总结并介绍了PTN在国内外的应用情况,指出了PTN今后的发展方向。

关键词：分组传送网 T-MPLS 可操作管理服务质量

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战术数据链网络建模与仿真

信息与电子工程 2012年第2期10卷 152-156页

作者：杨方方尹亚兰圣钱生海军指挥学院信息战研究系江苏南京211800

网络性能的优劣直接关系到战术数据链系统作战效能的发挥,对数据链网络系统性能的仿真评估具有一定的现实意义。在OMNeT++上搭建Link-16网络仿真模型,利用MiXiM对数据链网络系统节点的功能进行分层实现,并详细分析了各节点的系统响应时... 详细信息

网络性能的优劣直接关系到战术数据链系统作战效能的发挥,对数据链网络系统性能的仿真评估具有一定的现实意义。在OMNeT++上搭建Link-16网络仿真模型,利用MiXiM对数据链网络系统节点的功能进行分层实现,并详细分析了各节点的系统响应时延、端到端时延及丢包率对网络整体效能的影响,对进一步研究数据链网络具有一定的参考价值。

关键词：战术数据链 OMNeT++软件 MiXiM组件时延

基于DaVinci的自动对焦算法研究及实现

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通信技术 2012年第1期45卷 56-58,62页

作者：圣钱生张桂英吴有俊陈斌海军指挥学院浦口分院江苏南京211800

随着信息技术、超大规模集成电路技术、微电子技术的进一步发展,特别是高性能微处理器的使用,数字视频技术得以飞速发展。视频系统的基本功能是为了获取清晰图像,而自动对焦技术对图像质量影响很大。该文对自动对焦算法的关键技术进行研... 详细信息

随着信息技术、超大规模集成电路技术、微电子技术的进一步发展,特别是高性能微处理器的使用,数字视频技术得以飞速发展。视频系统的基本功能是为了获取清晰图像,而自动对焦技术对图像质量影响很大。该文对自动对焦算法的关键技术进行研究,提出了改进的自动对焦算法。搭建了基于达芬奇(DaVinci)DM6437处理器的硬件平台,并在该平台上实现了自动对焦。从对焦速度来看,完成一次对焦约需0.65 s,基本达到了系统的设计要求。

关键词： DaVinci自动对焦对焦评价函数窗口选择反馈控制

The YNEV stellar evolution and oscillation code

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Research in Astronomy and Astrophysics 2015年第4期15卷 549-568页

作者： qian-sheng Zhang Yunnan Observatories Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

We have developed a new stellar evolution and oscillation code YNEV, which calculates the structures and evolutions of stars, taking into account hydrogen and helium burning. A nonlocal turbulent convection theory and an updated over- shoot mixing model are optional in this code. The YNEV code can evolve low- and intermediate-mass stars from the pre-main sequence to a thermally pulsing asymptotic branch giant or white dwarf. The YNEV oscillation code calculates the eigenfrequen- cies and eigenfunctions of the adiabatic oscillations for a given stellar structure. The input physics and numerical scheme adopted in the code are introduced. Examples of solar models, stellar evolutionary tracks of low- and intermediate-mass stars with different convection theories （i.e. mixing-length theory and nonlocal turbulent con- vection theory）, and stellar oscillations are shown.

关键词： stars -- stellar structure -- stellar evolution -- stellar oscillations

The distribution of the periodic orbits with open deviation in C^(1+α)non-uniformly hyperbolic systems

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Science China Mathematics 2016年第1期59卷 161-168页

作者： qian sheng College of Science North China University of Technology

Let f ： M → M be a C^1＋α diffeomorphism on a smooth compact Riemannian manifold M and A be a Pesin set associated with the ergodic hyperbolic measure μ. Then f ： A → A forms a non-uniformly hyperbolic system. We concern with the distribution of the periodic orbits whose time averages are apart from the space average of μ. Finally, we derive a large deviation result for these periodic orbits with open deviation property.

关键词： specification open deviation non-uniformly hyperbolic

An improved nonlinear onboard adaptive model for aero-engine performance control

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Chinese Journal of Aeronautics 2023年第10期36卷 317-334页

作者： qian CHEN Hanlin sheng Tianhong ZHANG Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

The onboard adaptive model can achieve the online real-time estimation of performance parameters that are difficult to measure in a real aero-engine,which is the key to realizing modelbased performance *** must possess satisfactory numerical stability and estimation ***,the positive definiteness of the state covariance matrix may be destroyed in filter estimation because of the existence of some uncertain factors,such as the accumulated measurement error,noise,and disturbance in the strongly nonlinear engine system,inevitably causing divergence of estimates of Cholesky decomposition-based Spherical Unscented Kalman Filter(SUKF).Therefore,this paper proposes an improved SUKF algorithm(iSUKF)and applies it to the performance degradation estimation of the *** to SUKF,the iSUKF mainly replaces the Cholesky decomposition with the Singular Value Decomposition(SVD),which is numerically stable without any strict requirement for the state covariance ***,a correction factor is designed to assess the measurement deviation between the real engine and the nonlinear onboard model to correct the state covariance matrix,thus maintaining better numerical stability of parameters estimated by the ***,an offline correction strategy is also proposed to eliminate the influence of the degradation of unestimated health parameters or the filter’s inadequate estimation of the coupled health *** action effectively promotes the onboard adaptive model’s estimation accuracy concerning the degradation of the engine’real health parameters and its performance ***,the simulation results show that the iSUKF can maintain the numerical stability of the filter’s estimation of health *** with the existing methods,the offline correction strategy improves the estimation accuracy of the iSUKF-based nonlinear onboard adaptive model for the performance parameters of the real engine by more than 50%.The proposed met

关键词： Aero-engine Onboard adaptive model Spherical unscented Kalman filter Parameter estimation iSUKF

Asteroseismology of 16 Kepler Solar-like Stars:Stellar Parameters and the Effects of Element Diffusion

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Research in Astronomy and Astrophysics 2023年第7期23卷 206-220页

作者： Shuai Wang qian-sheng Zhang Yunnan Observatories Chinese Academy of Sciences396 YangfangwangGuandu DistrictKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China

Element diffusion has small but significant effects on the structure of the stellar *** is interesting to investigate the effects of element diffusion using *** have constructed two grids of stellar models,one with diffusion and one without,for solar-like stars with masses between 0.9 and 1.4 solar masses,and varied initial helium abundance and *** oscillation frequencies of all stellar models have also been *** Hermite cubic polynomials are adopted to interpolate stellar p-mode frequencies at an arbitrary age on a stellar evolutionary *** have investigated 16 Kepler solar-like stars by comparing the model frequencies with *** suggested ranges of stellar parameters and some global variables are *** all stars,the best model reproduces the observational frequencies with aχ^(2)of the order of *** has been found that element diffusion is important in modeling solar-like *** diffusion,the best value of the initial helium abundance is below the primordial helium abundance from Big Bang *** diffusion is taken into account,the required initial helium abundance increases to be higher than the primordial *** also generally improves the frequency fitting results by reducing the minimum ofχ^(2).Investigation of the second difference of the oscillation frequencies on KIC 8694723 and KIC 10454113 indicates that the current model of element diffusion may underestimate the strength of settling.

关键词： asteroseismology diffusion stars:interiors stars:abundances