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Flow Development Through HP&LP Turbines,PartⅡ:Effects of the hub Endwall Secondary Sealing Air Flow on the Turbine's Mainstream Flow

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Journal of Thermal Science 2017年第4期26卷 308-315页

作者： hu Jialin DU Qiang LIU Jun WANG pei LIU Guang LIU Hongrui DU Meimei Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China Graduate University of Chinese Academy of Sciences Beijing 100049China Petroleum Production Engineering Research Institute of huabei Oilfield Company Renqiu Hebei 062550China

Although many literatures have been focused on the underneath flow and loss mechanism, very few experiments and simulations have been done under the engines' representative working conditions or considering the real cavity structure as a whole. This paper aims at realizing the goal of design of efficient turbine and scrutinizing the velocity distribution in the vicinity of the rim seal. With the aid of numerical method, a numerical model describing the flow pattern both in the purge flow spot and within the mainstream flow path is established, fluid migration and its accompanied flow mechanism within the realistic cavity structure(with rim seal structure and considering mainstream & secondary air flow's interaction) is used to evaluate both the flow pattern and the underneath flow mechanism within the inward rotating cavity. Meanwhile, the underneath flow and loss mechanism are also studied in the current paper. The computational results show that the sealing air flow's ingestion and ejection are highly interwound with each other in both upstream and downstream flow of the rim seal. Both the downstream blades' potential effects as well as the upstream blades' wake trajectory can bring about the ingestion of the hot gas flow within the cavity, abrupt increase of the static pressure is believed to be the main reason. Also, the results indicate that sealing air flow ejected through the rear cavity will cause unexpected loss near the outlet section of the blades in the downstream of the HP rotor passages.

关键词： Turbines Sealing air Flow pattern

Analysis of Spatio-Temporal Changes of Land Usein Xuzhou City Based on Remote Sensing

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Journal of China University of Mining and Technology 2006年第2期16卷 151-155页

作者： hu Zhao-ling DU pei-jun GUO Da-zhi School of Urban and Environmental Science Xuzhou Normal University Xuzhou Jiangsu 221116 China School of Environmental Sciences and Spatial lnformatics. China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Based on the satellite remote sensing TM/ETM images of Xuzhou city, basic data about land use of the city from 1994 to 2000 are obtained with the neural network classification module of PCI software, and the dynamic con- version matrix of land use is thus calculated. The areas of construction land and water body have increased by 1833.93 hm2 and 804.87 hm2, respectively. On the contrary, the area of cropland has decreased by 3207.24 hm2. The area of cropland converted into construction land makes up 26.84%, and that converted into water body amounts for 8.17% of the total area of cropland in 1994. The variation index of land use degree and the dynamic degree index of land use computed are 1.38 and 57.81%, respectively, which demonstrate that land use in Xuzhou is in a development period and the changes are drastic. The frequency index and importance index of the form in which cropland converted into con- struction land are 29.91% and 68.93% respectively. The results indicate that the change is not only widespread in space but a major form of spatial change of land use in the area.

关键词： remote sensing image land use spatio-temporal change Xuzhou city

Improved mechanical properties of Ni-rich Ni3Al coatings produced by EB-PVD for repairing single crystal blades

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Rare Metals 2017年第7期36卷 556-561页

作者： Jing-Yong Sun Yan-Ling pei Shu-Suo Li hu Zhang Sheng-Kai Gong School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Active control of turbine blade tip clearance for aircraft engine continues to be a concern in engine opera- tion, because turbine blades are subjected to wear and therefore cause an increasing tip clearance between the rotating blades and the shroud and also reduce the engine efficiency. In this work, a Ni-rich Ni3A1 coating with γ＇/γ two-phase microstructure was deposited by electron beam physical vapor deposition （EB-PVD）, which worked as repairing the worn blade tips of single crystal blades. Nb molten pool was used to increase the molten pool tem- perature and thus to enhance the deposition rate. The microstructures and mechanical properties can be modified by the deposition temperatures and the following heat treatments. All coatings consist of γ＇ and γ phases. At deposition temperature of 600 ℃, a dense microstructure can be achieved to produce a coating with grain size of 1 μm and microhardness of -HV 477. After being heated for 4 h at a temperature of 1,100 ℃, the coatings have a more uniform microstructure, and microhardness maintains at a high level of -HV 292. Effect of Hf and Zr on EB-PVD Ni3Al repair coating will be further investigated.

关键词： Repair coating Ni3A1 Electron beamphysical vapor deposition Blades tips Single crystal Heat treatment

LA-ICP-MS zircon U-Pb dating from granitoids in southern basement of Songliao basin:Constraints on ages of the basin basement

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Science China Earth Sciences 2007年第7期50卷 995-1004页

作者： GAO FuHong XU WenLiang YANG DeBin pei FuPing LIU XiaoMing hu ZhaoChu College of Earth Sciences Jilin UniversityChangchun 130061China The Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China

Seven LA-ICP-MS zircon U-Pb datings from granitoids in the southern basement of the Songliao basin were done in order to constrain the ages of the basin basement. The cathodoluminescence (CL) images of the zircons from seven granitoids indicate that they are euhedral-subhedral ones with striped ab-sorption and obvious oscillatory zoning rims. The dating results show that a weighted mean 206Pb/238U age is 236±3 Ma for quartz diorite (sample No.T6-1) located in the western slope of the basin,that weighted mean 206Pb/238U ages are 319±1 Ma (2126 m) and 361±2 Ma (1994 m) for diorite (sample ***1-1) and granite (sample ***1-2) located in northern part of southeastern uplift of the basin,respectively,and that weighted mean 206Pb/238U ages are 161±5 Ma,165±2 Ma,165±1 Ma and 161±4 Ma for samples Q2-1,SN121,SN122,and SN72 granitoids located in southern part of southeastern uplift of the basin,respectively. The statistical results of ages suggest that the middle Jurassic granitoids con-stitute the main part of basement granitoids,and that the Hercynian and Indo-Sino magmatisms also occur in the basin basement. It is implied that the Songliao basin should be a rift one formed in the intracontinent or active continental margin settings in the late Mesozoic after the Middle Jurassic orogeny took place.

关键词： Songliao basin basement granitoid zircon LA-ICP-MS U-Pb dating

Acoustic cloak constructed with thin-plate metamaterials

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International Journal of Smart and Nano Materials 2015年第1期6卷 73-83页

作者： pei Li Xuebing Chen Xiaoming Zhou Gengkai hu Ping Xiang Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Educationand School of Aerospace EngineeringBeijing Institute of Technology100081BeijingChina Systems Engineering Research Institute 100036BeijingChina

We propose a strategy for designing the cylindrical acoustic cloak with thin-plate *** inhomogeneous cloaking shell as derived by transformation acoustics is first discretized into a three-layer anisotropic metafluid,and their material parameters are optimized by minimizing the external *** these metafluids are practically realized by thin-plate structures according to the metamaterial *** an example,an acoustic cloak is designed with nine layers of thin plate and totally 900 plate *** simulations are performed to assess the cloaking performance of the designed structure.

关键词： acoustic cloak thin-plate metamaterial optimization

Albumin-bound paclitaxel dimeric prodrug nanoparticles with tumor Qr redox heterogeneity-triggered drug release for synergistic photothermal/ chemotherapy

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Nano Research 2019年第4期12卷 877-887页

作者： Qing pei Xiuli hu Xiaohua Zheng Rui Xia Shi Liu Zhigang Xie Xiabin Jing State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 I China University of Science and Technology of China Hefei 230026 China

In spired by the clinically approved albumin based PTX formulatio n(Abraxa ne)and high-drug-loading dimeric prodrug tactics,herein we report a theranostic HAbraxane-likeH prodrug formulation,which is comprised of human serum albumin(HSA),a paclitaxel(PTX)dimer bridged with thioether liner(PTX2-S),and photosensitizer IR780 ***(NPs)with PTX2-S and IR780 as the core and HSA as the stealth shell are *** with HSA-based PTX clinical formulation(Abraxane),the dimeric molecules not only constitute the bulk structure of the particles,but also act as crossi ng age nt,thus realizing drug loadi ng content in creasi ng from 6.6 wt.%to 48.7 wt.%with high loadi ng efficie ncy(>90%)and excellent stability in biological *** ntly,the thioether lin kage dually resp onds to the tumor redox heteroge neity and the NPs gradually releases the pare nt drug PTX for *** nwhile,PTX2-S facilitates the en capsulatio n of IR780 iodide due to their π-π stacki ng interaction and IR780 iodide gen erates spatio-temporal hyperthermia un der light irradiation to kill cancer cells for photothermal *** described craft integrates the biomimetic trait of HSA,high drug loading,tumor redox heterogeneity-initiated on-dema nd drug release,and combi nation therapy into one formulati on and the developed nan oparticles are promising for cancer treatment.

关键词： human serum albumin prodrug nanoparticles tumor redox heterogeneity-responsiveness controlled drug release synergistic cancer therapy

Review of the deep learning for food image processing

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International Journal of Agricultural and Biological Engineering 2024年第5期17卷 15-30页

作者： Chenrui Niu Xiayang Ying Gan pei Menghan hu Guangtao Zhai Shanghai Key Laboratory of Multidimensional Information Processing School of Communication and Electronic EngineeringEast China Normal UniversityShanghai 200241China Department of General Surgery Pancreatic Disease CenterRuijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025China Istitute of Image Communication and Network Engineering Shanghai Jiao Tong University Shanghai 200240China

As deep learning techniques are increasingly applied with greater depth and sophistication in the food industry,the realm of food image processing has progressively emerged as a central focus of research *** work provides an overview of key practices in food image processing techniques,detailing common processing tasks including classification,recognition,detection,segmentation,and image retrieval,as well as outlining metrics for evaluating task performance and thoroughly examining existing food image datasets,along with specialized food-related *** terms of methodology,this work offers insight into the evolution of food image processing,tracing its development from traditional methods extracting low and intermediate-level features to advanced deep learning techniques for high-level feature extraction,along with some synergistic fusion of these *** is believed that these methods will play a significant role in practical application scenarios such as self-checkout systems,dietary health management,intelligent food service,disease etiology tracing,chronic disease management,and food safety ***,due to the complex content and various types of distortions in food images,further improvements in related methods are needed to meet the requirements of practical applications in the *** is believed that this study can help researchers to further understand the research in the field of food imaging and provide some contribution to the advancement of research in this field.

关键词： deep learning food image processing feature extraction dietary health

Direct Photolithography of WO_x Nanoparticles for High-Resolution Non-Emissive Displays

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NANO-MICRO LETTERS 2025年第1期17卷 1-13页

作者： Gu, Chang Yang, Guojian Wang, Wenxuan Shi, Aiyan Fang, Wenjuan Qian, Lei hu, Xiaofei Zhang, Ting Xiang, Chaoyu Zhang, Yu-Mo Chinese Acad Sci Ningbo Inst Mat Technol & Engn Lab Optoelect Informat Technol & Devices Ningbo 315201 Peoples R China Qianwan Inst CNITECH Hangzhou Bay Lab Adv Nanooptoelectron Mat & Device Ningbo 315336 Peoples R China Zhejiang Univ Innovat Ctr Yangtze River Delta Smart Mat Architecture Res Lab Jiaxing 314100 Peoples R China Univ Sci & Technol China Hefei 230026 Peoples R China Jilin Univ Coll Chem State Key Lab Supramol Struct & Mat Changchun 130012 Peoples R China

High-resolution non-emissive displays based on electrochromic tungsten oxides (WOx) are crucial for future near-eye virtual/augmented reality interactions, given their impressive attributes such as high environmental stability, ideal outdoor readability, and low energy consumption. However, the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron scale. Here, we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand exchange. This strategy enabled us to achieve ultra-high resolution efficiently (line width m, the best resolution for reported inorganic electrochromic materials). Additionally, the resulting device exhibited impressive electrochromic performance, such as fast response ( 3600 cycles), as well as promising applications in electronic logos, pixelated displays, flexible electronics, etc. The success and advancements presented here are expected to inspire and accelerate research and development (R&D) in high-resolution non-emissive displays and other ultra-fine micro-electronics.

关键词： Electrochromic Direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays

Source identification of aluminum in surface sediments of the Yellow Sea off the Shandong Peninsula

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Acta Oceanologica Sinica 2015年第12期34卷 147-153页

作者： XU Gang LIU Jian pei Shaofeng KONG Xianghuai hu Gang GAO Maosheng Qingdao Institute of Marine Geology Ministry of Land and Natural Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Ministry of Land and Natural Resources for Marine Hydrocarbon Resources and Environment Geology Key Laboratory of China Geological Survey Bureau for Coastal Wetland Biogeosciences

Surface sediment samples in the near shore area of the north Shandong Peninsula are collected for grain size and element analyses. The results indicate that the surface sediments in the study area are primarily composed of the silt-sized components similar to the huanghe River. The total concentration of aluminum varies from 5.57% to7.37%（average（6.33 ± 0.40）%）, and its spatial distribution is mainly controlled by the grain size. Correlations between the ratio of aluminum to titanium concentration and aluminum concentration, titanium concentration and the mean grain size indicate that aluminum in the near shore surface sediments is affected majorly by the terrigenous source, and partially by the anthropogenic source. The ratios of aluminum to titanium concentrations are larger than the background value of loess matter at some stations due to the existence of excess aluminum associated with human activities. Thus, the sources of aluminum should be identified firstly when aluminum is used as an index of terrigenous matter even in the near shore area dominated by terrigenous deposits.

关键词： aluminum source identification surface sediments Shandong Peninsula Yellow Sea