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中国有色金属学会会刊：英文版 1999年第2期9卷 56-60页

作者： pan, Hongge Zhejiang Univ Hangzhou China

１ＩＮＴＲＯＤＵＣＴＩＯＮＭｅｔａｌｈｙｄｒｉｄｅｓｈａｖｅｂｅｅｎｕｓｅｄａｓｎｅｇａｔｉｖｅｅｌｅｃｔｒｏｄｅｓｏｆｎｉｃｋｅｌ／ｍｅｔａｌｈｙｄｒｉｄｅｂａｔｅｒｉｅｓｉｎｐｌａｃｅｏｆｃａｄｍｉｕｍ，ｂｅｃａ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＭｅｔａｌｈｙｄｒｉｄｅｓｈａｖｅｂｅｅｎｕｓｅｄａｓｎｅｇａｔｉｖｅｅｌｅｃｔｒｏｄｅｓｏｆｎｉｃｋｅｌ／ｍｅｔａｌｈｙｄｒｉｄｅｂａｔｅｒｉｅｓｉｎｐｌａｃｅｏｆｃａｄｍｉｕｍ，ｂｅｃａｕｓｅｏｆｔｈｅｉｒｈｉｇｈｅｎｅ...

关键词： electrochemical overpotentialconcentration overpotentialanodic polarizationhydrogen storage alloy

Geochronology and Geochemistry of Wangjiadashan Quartz Syenite Porphyry in Suizao Area of Hubei Province in the Tongbai-Dabie Orogenic Belt

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Journal of Earth Science 2023年第3期34卷 790-805页

作者： pan-pan Niu Shao-Yong Jiang State Key Laboratory of Geological Processes and Mineral Resources School of Earth ResourcesChina University of GeosciencesWuhan 430074China Key Laboratory of Geological Survey and Evaluation of Ministry of Education China University of GeosciencesWuhan 430074China Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of GeosciencesWuhan 430074China

The Wangjiadashan area in Suizhou-Zaoyang region of Hubei Province in the Tongbai-Dabie orogenic belt hosts important copper-gold deposits and contains a large number of quartz syenite porphyry dykes,occurring mostly along the NEE-trend *** this study,we used LA-ICP-MS zircon U-Pb dating method and obtained an age of 143.6±1.4 Ma,which represents the emplacement of these quartz syenite porphyry dykes was at the Yanshanian,but it was slightly earlier than the previously reported ages(139-135 Ma)for granites widespreading in Suizao *** geochemical data of the Wangjiadashan quartz syenite porphyry show high K_(2)O,CaO,Na_(2)O and Al_(2)O_(3)contents but extremely low MgO contents(0.01 wt.%-0.46 wt.%).The geochemical characteristics indicate that these quartz syenite porphyry dykes belong to the typical C-type adakite and were possibly formed in the post-collisional ***-isotopic(Sr-Nd-Pb-Hf)analyses indicate that these quartz syenite porphyry dykes were originated from crust without distinct mantle materials *** is suggested that the Wangjiadashan quartz syenite porphyry was generated from partial melting of the thickened lower continental crust,and garnet but no plagioclase was left as residual *** with the widespread granites of the Tongbai area,the Wangjiadashan quartz syenite porphyry formed earlier and derived from more juvenile and K-rich lower crust,while they all belong to intensive magmatism concentrated during the Early Cretaceous epoch in the Tongbai area.

关键词： quartz syenite porphyry zircon U-Pb dating geochemistry Sr-Nd-Pb-Hf isotopes petrogenesis Wangjiadashan Tongbai Orogen

Compressive Mechanical Characteristics of Multi-layered Gradient Hydroxyapatite Reinforced Poly(Vinyl Alcohol) Gel Biomaterial

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Journal of Materials Science & Technology 2013年第6期29卷 551-556页

作者： Yusong pan Qianqian Shen Chengling pan Jing Wang School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan 232001China

Functional gradient materials provided us a new concept for artificial articular cartilage design with gradient component and gradient structure where one side of the material is high free water content thereby providing excellent lubrication function and the opposite side of the material is high hydroxyapatite content, thereby improving the bioactivity of the material and stimulating cell growth. The goal of the present study was to develop a multi-layered gradient HA/PVA gel biocomposites through layer-by-layer casting method combing with freeze/thaw cycle technology. The various influence factors on the compressive strength and modulus of the multi-layered gradient biocomposites were investigated. The results showed that the compressive mechanical characteristics of the biocomposites were similar to that of natural articular cartilage. Both the compressive strength and modulus of the multi-layered gradient HA/PVA gel biocomposites increased exponentially with the rise of compressive strain ratio. Both the compressive strength and average compressive modulus of the biocomposites improved with the rise of freeze/thaw cycle times and total concentration of HA particles in the biocomposites, but they showed decreasing tendency with the rise of HA concentration difference between adjacent layers.

关键词： Multi-layered gradient HA/PVA gel biocomposites Freeze/thaw cycle times Strength Modulus

Image-based 3D model retrieval using manifold learning

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1397-1408页

作者： pan-pan MU San-yuan ZHANG Yin ZHANG Xiu-zi YE Xiang pan College of Computer Science and Technology Zhejiang University College of Mathematics and Information Science Wenzhou University College of Computer Science and Technology Zhejiang University of Technology

We propose a new framework for image-based three-dimensional(3D) model retrieval. We first model the query image as a Euclidean point. Then we model all projected views of a 3D model as a symmetric positive definite(SPD) matrix, which is a point on a Riemannian manifold. Thus, the image-based 3D model retrieval is reduced to a problem of Euclid-to-Riemann metric learning. To solve this heterogeneous matching problem, we map the Euclidean space and SPD Riemannian manifold to the same high-dimensional Hilbert space, thus shrinking the great gap between them. Finally, we design an optimization algorithm to learn a metric in this Hilbert space using a kernel trick. Any new image descriptors, such as the features from deep learning, can be easily embedded in our framework. Experimental results show the advantages of our approach over the state-of-the-art methods for image-based 3D model retrieval.

关键词： Model retrieval Euclidean space Riemannian manifold Hilbert space Metric learning

Advances and challenges in developing cocatalysts for photocatalytic conversion of carbon dioxide to fuels

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Nano Research 2022年第12期15卷 10090-10109页

作者： Qian Wang Zhenhua pan Graduate School of Engineering Nagoya UniversityFuro-choChikusa-kuNagoya464-8603Japan Institute for Advanced Research Nagoya UniversityFuro-choChikusa-kuNagoya464-8601Japan Department of Applied Chemistry Faculty of Science and TechnologyChuo University1-13-27 KasugaBunkyoTokyo112-8551Japan

The global adoption of efficient sustainable energy sources is a crucial step toward meeting energy demands while achieving carbon emission reduction *** energy has become a clean and cost-competitive alternative to traditional fossil fuels,but the intermittent nature of sunlight results in challenges associated with energy storage and *** carbon dioxide reduction intends to mimic natural photosynthesis for utilizing sunlight to chemically convert water and CO_(2) into *** this process,the solar energy is captured and stored in fuels,so-called solar fuels,for widespread on-demand *** solar fuel production systems are multi-component,comprising light-harvesting(photosensitizer)and catalytic(cocatalyst)*** are indispensable for photocatalytic CO_(2) reduction systems,which promote charge carrier separation and transport,reduce the reaction activation energy,and alter the reaction route,thereby enhancing the activity and selectivity of the photocatalytic *** review presents a comprehensive summary of the recent advancements in cocatalysts for photocatalytic CO_(2) reduction reaction(CO_(2)RR),with the purpose of providing new insights and guidance to the field with regard to research directions and best *** summarize how various cocatalysts including inorganic nanoparticles,metal complexes,enzymes,and bacteria can be combined with semiconductor photosensitizer for light-driven photocatalytic CO_(2)***-by-side comparisons reveal the strengths and limitations of each kind of cocatalysts and how lessons extracted from studying natural photosynthetic systems can be applied to investigations of artificial photosynthesis,presenting an outlook discussing possible future concepts for a more effective photocatalytic CO_(2) reduction process.

关键词： photocatalysis cocatalyst carbon dioxide reduction artificial photosynthesis solar fuel production

Effect of Rotor-stator Axial Gap on the Tip Seal Leakage Flow of a Steam Turbine

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Journal of Thermal Science 2021年第3期30卷 973-982页

作者： LI pan CAO Lihua School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The tip leakage flow in different axial gaps is numerically investigated based on the Reynolds-Averaged Navier-Stokes equations and k-ω SST turbulent model using commercial CFD software ANSYS *** characteristics of vortexes in the flow field of tip seal and the distribution law of rotor tip leakage loss are analyzed under the change of axial *** results show that the flow field in the blade tip seal undergoes complex changes with the increase of axial *** are two opposite vortices in the seal cavity with small axial gap,namely,the large vortex in the cavity and the small vortex near the wall of the *** small vortex gradually disappears with the increase of the axial *** the axial gap is increased to a certain value,the reverse large vortex is formed in the cavity behind the low teeth of seal,and the leakage rate increases significantly;the steam flow angle and the mixing loss also show different *** on the traditional calculation formula of tip leakage rate,a more accurate calculation formula of tip leakage rate is constructed by introducing equivalent labyrinth seal teeth to consider the variation of axial gap.

关键词： steam turbine axial gap tip leakage labyrinth seal prediction formulation

Red/NIR/SWIR multi-band persistent luminescent nanoparticles as ultrasensitive multi-channel tracers in water and crude oil/water emulsions

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Nano Research 2023年第11期16卷 12706-12712页

作者： Yafei Chen Zhengwei pan Center for Integrative Petroleum Research College of Petroleum Engineering and GeosciencesKing Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

We report the use of CaTiO_(3):Pr^(3+)multiband persistent luminescent nanoparticles,which can simultaneously emit red(610 nm),near-infrared(893 nm),and short-wave infrared(1040 nm)photoluminescence and persistent luminescence,as the tracer nanoagents for water tracer *** using a spectrofluorometer,an Si charge-coupled device(CCD)camera and an InGaAs array camera as the detection tools,we evaluated the sensing capabilities of the three emission bands of CaTiO_(3):Pr^(3+)nanoparticles in brine water solutions and crude oil/brine water emulsions in both photoluminescence mode and persistent luminescence *** these different detection combinations,the persistent luminescence-based Si CCD camera imaging exhibits the best sensing performance with the detection limits being at a single-digit ppb level for the 610 and 893 nm bands and about 100–200 ppb for the 1040 nm band in both water solutions and crude oil/water emulsions,while the photoluminescencebased Si CCD camera imaging has a much higher detection limit of~10 ppm in water solutions and of~200 ppm in oil/water *** persistent luminescence-based InGaAs array camera imaging to the 1040 nm band has the worst performance with the detection limits higher than 200 ppm for both *** sensing performances of the spectrofluorometer to photoluminescence signals and persistent luminescence signals in the two solutions are about the same,with the detection limits being around 100–200 ppm.

关键词： water tracer CaTiO_(3):Pr^(3+)nanoparticles photoluminescence persistent luminescence crude oil/water emulsion detection limit

Third-order unconditional positivity-preserving schemes for reactive flows keeping both mass and mole balance

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Chinese Journal of Aeronautics 2023年第11期36卷 24-41页

作者： Jianhua pan Luxin Li Zhejiang Provincial Engineering Research Center for the Safety of Pressure Vessel and Pipeline Ningbo UniversityNingbo 315211China Key Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo 315211China

In this paper,the previously proposed second-order process-based modified Patankar Runge-Kutta schemes are extended to the third order of *** to the process-based implicit handling of reactive source terms,the mass conservation,mole balance and energy conservation are kept simultaneously while the positivity for the density and pressure is preserved unconditionally even with stiff reaction *** is proved that the first-order truncation terms for the Patankar coefficients must be zero to achieve a prior third order of accuracy for most cases.A twostage Patankar procedure for each Runge-Kutta step is designed to eliminate the first-order truncation terms,accomplish the prior third order of accuracy and maximize the Courant number which the total variational diminishing property *** the same approach as the second-order schemes,the third-order ones are applied to Euler equations with chemical reactive source *** studies including both 1D and 2D ordinary and partial differential equations are conducted to affirm both the prior order of accuracy and the positivity-preserving property for the density and pressure.

关键词： Chemical reactions Positivity-preserving Patankar schemes Mass conservation Mole balance Third-order schemes

Lightweight privacy-preserving truth discovery for vehicular air quality monitoring

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Digital Communications and Networks 2023年第1期9卷 280-291页

作者： Rui Liu Jianping pan Department of Computer Science University of VictoriaVictoriaBCV8P 5C2Canada

Air pollution has become a global concern for many *** crowdsensing systems make it possible to monitor air quality at a fine *** better utilize the sensory data with varying credibility,truth discovery frameworks are ***,in urban cities,there is a significant difference in traffic volumes of streets or blocks,which leads to a data sparsity problem for truth *** the privacy of participant vehicles is also a crucial *** first present a data masking-based privacy-preserving truth discovery framework,which incorporates spatial and temporal correlations to solve the sparsity *** further improve the truth discovery performance of the presented framework,an enhanced version is proposed with anonymous communication and data *** frameworks are more lightweight than the existing cryptography-based *** also evaluate the work with simulations and fully discuss the performance and possible extensions.

关键词： Privacy preserving Truth discovery Crowdsensing Vehicular networks

Siegmund Duality for Continuous Time Markov Chains on Z_+~d

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Acta Mathematica Sinica,English Series 2018年第9期34卷 1460-1472页

作者： pan ZHAO Department of Basic Courses Beijing Union University

For the continuous time Markov chain with transition function P（t） on Z d ＋ , we give the necessary and sufficient conditions for the existence of its Siegmund dual with transition function P - （t）. If Q, the q-matrix of P（t）, is uniformly bounded, we show that the Siegmund dual relation can be expressed directly in terms of q-matrices, and a sufficient condition under which the Q-function is the Siegnmnd dual of some Q-function is also given.

关键词： Continuous time Markov chains the Siegmund dual Mobius function ↑-Mobius mono-tonicity Feller Reuter Riley transition functions birth and death chains