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Design and Application of Turbine Cascade Partitioned Endwall Profiling

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Journal of Thermal Science 2025年第1期34卷 110-128页

作者： ZENG fei JIANG Ruiqi xue Xingxu DU Wei LUO Lei ZHOU Xun AECC Hunan Aviation Powerplant Research Institute School of Energy Science and Technology Harbin Institute of Technology Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research Institute

The influence of partitioned profiling design based on a large-pitch highly loaded cascade is studied by numerical *** partitioned profile is mainly composed of a pressure-side convex structure near the leading edge and a suction-side convex structure at the midstream and downstream sides of the *** influence of the change in the vertex axial position and peak value of the B-line on the secondary flow control is *** this paper,air(ideal gas) is selected as the flow *** average static pressure at the outlet and the average total temperature at the inlet are kept *** γ-θ is used as the turbulence *** results show that the pressure-side convex structure suppresses the spanwise and pitchwise migration of the inlet flow by adjusting the static pressure distribution of the flow field,so the development of the pressure-side leg of the horseshoe vortex is effectively *** suction-side convex structure adjusts the static pressure distribution of the flow field and increases the included angle between the cross-flow and suction surface,so the accumulation of low-momentum fluid,the development of a corner vortex and the flow separation at the trailing edge of the suction-side surface are all suppressed near the endwall-suction ***,the energy loss coefficient of the large-pitch highly loaded cascade is decreased from 0.0564 to 0.0485,representing a 25% reduction in secondary flow losses.

关键词： Vortex flow

采用钠化焙烧-还原浸出联合工艺从废Pd/Al_(2)O_(3)催化剂中经济高效回收Pd和Al_(2)O_(3)

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Transactions of Nonferrous Metals Society of China 2023年第7期33卷 2245-2254页

作者：董中林李骞饶雪飞徐斌杨永斌董海刚姜涛中南大学资源加工与生物工程学院长沙410083 昆明贵金属研究所铂金属综合利用先进技术国家重点实验室昆明650106

开发了钠焙烧-还原浸出联合工艺从废Pd/Al_(2)O_(3)催化剂中回收Pd和Al_(2)O_(3)。钠化焙烧热力学分析表明,在最佳的Na_(2)O/Al_(2)O_(3)摩尔比和温度下,NaOH、Na_(2)CO_(3)和Na_(2)C2O4均可以与Al_(2)O_(3)完全反应生成Na Al O2。NaOH、Na_(2)CO_(3)和Na_(2)C_(2)O_(4)的焙烧渣经水浸后,Al_(2)O_(3)浸出率分别为99.6%、61.0%和55.3%。机械活化-NaOH无水焙烧工艺避免了焙烧渣的固结且可获得较高的Al_(2)O_(3)浸出率。N_(2)H_(4)·H_(2)O还原浸出避免了水浸过程中Pd的溶解损失且催化剂中99.7%的Al_(2)O_(3)被浸出。最终得到Na Al O2浸出液和富钯渣,其中有价的铝和钯可被进一步回收。

关键词：废Pd/Al_(2)O_(3)催化剂 Pd和Al_(2)O_(3)的回收钠化焙烧机械活化还原浸出

Ground-layer Adaptive Optics for the 2.5 m Wide-field and High-resolution Solar Telescope

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Research in Astronomy and Astrophysics 2024年第3期24卷 224-236页

作者： Ying Yang Lan-Qiang Zhang Nan-fei Yan Jin-Sheng Yang Zhen Li Teng-fei Song xue-Jun rao Chang-Hui rao Key Laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China School of Electronic Electrical and Communication Engineering of the University of Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern A&A Ministry of EducationNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216.China

The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar *** aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5′,and a desired resolution of 0.3″.To meet the scientific requirements of WeHoST,the ground-layer adaptive optics(GLAO)with a specially designed wave front sensing system is as the primary *** introduce the GLAO configuration,particularly the wave front sensing *** analytic method,we simulate the performance of both classical AO and GLAO systems,optimize the wave front sensing system,and evaluate GLAO performance in terms of PSF uniformity and correction improvement across whole *** results indicate that,the classical AO will achieve diffraction-limited resolution;the suggested GLAO configuration will uniformly improve the seeing across the full 5′×5′FOV,reducing the FWHM across the axis FOV to less than0.3″(λ≥705 nm,r0≥11 cm),which is more than two times *** specially designed wave front sensor schedule offers new potential for WeHoST’s GLAO,particularly the multi-FOV GLAO and the flexibility to select the detected *** capabilities will significantly enhance the scientific output of the telescope.

关键词： instrumentation adaptive optics-instrumentation detectors-instrumentation high angular resolution-methods numerical-telescopes-Sun activity

Electrochemical energy storage applications of “pristine” graphene produced by non-oxidative routes

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Science China(Technological Sciences) 2015年第11期58卷 1841-1850页

作者： LIU fei xue DongFeng State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Graphene is a promising material as both active components and additives in electrochemical energy storage devices. The properties of graphene strongly depend on the fabrication methods. The applications of reduced graphene oxide as electrode materials have been well studied and reviewed, but the using of "pristine" graphene as electrode material for energy storage is still a new topic. In this paper, we review state-of-the-art progress in the fabrication of "pristine" graphene by different methods and the electrochemical performance of graphene-based electrodes. The achievements in this area will be summarized and compared with the graphene oxide route in terms of cost, scalability, material properties and performances, and the challenges in these methods will be discussed as well.

关键词： pristine graphene energy storage exfoliation electrochemical

Learning Bayesian networks using genetic algorithm

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Journal of Systems Engineering and Electronics 2007年第1期18卷 142-147页

作者： Chen fei Wang Xiufeng rao Yimei Coll. of Information Technical Science Nankal Univ. Tianjin 300071 P. R. China

A new method to evaluate the fitness of the Bayesian networks according to the observed data is provided. The main advantage of this criterion is that it is suitable for both the complete and incomplete cases while the others not. Moreover it facilitates the computation greatly. In order to reduce the search space, the notation of equivalent class proposed by David Chickering is adopted. Instead of using the method directly, the novel criterion, variable ordering, and equivalent class are combined,moreover the proposed mthod avoids some problems caused by the previous one. Later, the genetic algorithm which allows global convergence, lack in the most of the methods searching for Bayesian network is applied to search for a good model in thisspace. To speed up the convergence, the genetic algorithm is combined with the greedy algorithm. Finally, the simulation shows the validity of the proposed approach.

关键词： Bayesian networks Genetic algorithm Structure learning Equivalent class

Synthesis and Optical Properties of ZnO Nanoparticles in Submicron PS Hollow Reactors

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Chinese Journal of Chemical Physics 2012年第6期25卷 719-724,I0004页

作者： xue-feng Huang fei-fei Ju Mo-zhen Wang xue-wu Ge CAS Key Laboratory of Soft Matter Chemisry Department of Polymer Science and EngineeringUniversity of Science and Technology of China Hefei 230026 China

ZnO nanoparticles were first encapsulated in submicron PS hollow microspheres through two-step swelling process of core-shell structured PMMA/PS （PMMA： polymethyl methao- rylate） microspheres in acid-alkali solution, and the ZnO precursors, i.e. the ethanol solu- tions of （CHaCOO）2Zn and LiOH. The transmission electron microscope, X-ray diffraction, and thermogravimetric analysis results show that the feeding order of ethanol solutions of （CH3COO）2Zn and LiOH in the second swelling step has great influence on the loading efficiency and the size of ZnO nanoparticles, but little on their crystal form. The photolumi- nescence and UV-Vis absorption behavior of ZnO/PS microspheres show that the PS shell can effectively avoid the fluorescence quenching effect.

关键词： ZnO/PS hybrid material Core-shell polymer Swelling PS hollow microsphere Optical property

Study of pollutant transport in depth-averaged flows using random walk method

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Journal of Hydrodynamics 2019年第2期31卷 303-316页

作者： xue-fei Wu Dongfang Liang School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Department of Engineering University of CambridgeCambridgeUK

The random walk particle tracking(RWPT)method is compared with the Eulerian methods in investigating pollutant transport in depth-averaged *** a typical representative of the Eulerian model with high performance,the MacCormack scheme with Total Variation Diminishing modification(TVD-Mac)is selected for *** concentration is simulated in four case ***,both numerical models have been tested in two idealized cases and compared against analytical *** dissipation is observed for TVD-Mac model where the concentration changes abruptly,especially under the circumstances of low resolution and misalignment between the flow direction and grid *** the contrary,simulations by the random walk model achieve higher accuracy in both cases and are free of fictitious oscillations in the vicinity of sharp concentration ***,the solute oscillation along a one-dimensional hypothetical tidal estuary is simulated,with the RWPT accurately con serving mass and suffering less rm merical diffusion compared with the Eulerian ***,the process of pollutant transport in a Yangzte River reach is predicted by the *** longitudinal dispersion coefficient DL is calculated *** is compared favorably with the theoretical/empirical formulae,indicating the validity of the RWPT in solving complex natural problems.

关键词： Pollutant transport depth-averaged flows random walk particle tracking TVD-MacCormack

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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Genomic and transcriptomic analyses reveal metabolic complementarity between whiteflies and their symbionts

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Insect Science 2022年第2期29卷 539-549页

作者： Dan-Tong Zhu Qiong rao Chi Zou fei-xue Ban Juan-Juan Zhao Shu-Sheng Liu Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects Institute of Insect SciencesZhejiang UniversityHangzhou310029 China School of Agriculture and Food Science Zhejiang Agriculture and Forestry UniversityLin'anHangzhou311300 China

Nutritional mutualism between insects and symbiotic bacteria is *** various sap-feeding whitefly species within the Bemisia tabaci complex associate with the same obligate symbiont(Portiera)and multiple secondary *** is often assumed that some of the symbionts residing in the whiteflies play crucial roles in the nutritional physiology of their insect *** effort has been made to understand the functions of the whitefly symbionts,the metabolic complementarity offered by these symbionts to the hosts is not yet well *** examined two secondary symbionts,Arsenophonus and Wolbachia,in two species of the *** whitefly complex,provisionally named as Asia II 3 and China *** sequence analyses revealed that Arsenophonus and Wolbachia retained genes responsible for the biosynthesis of B *** then conducted transcriptomic surveys of the bacteriomes in these two species of whiteflies together with that in another species named MED of this whitefly complex previously *** analyses indicated that several key genes in B vitamin syntheses from the three whitefly species were *** findings suggest that,similar to another secondary symbiont Hamiltonella,Arsenophonus and Wolbachia function in the nutrient provision of host *** phylogenetically distant species of symbionts are associated with their respective hosts,they have evolved and retained similar functions in biosynthesis of some B *** metabolic complementarity between whiteflies and symbionts represents an important feature of their coevolution.

关键词： symbiont B vitamins complement evolution whitefly