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Enhancement of weathered crust elution-deposited rare earth ores leaching process with PQ-10 addition

Journal of Rare Earths 2025年第1期43卷 180-190,I0007页

作者： Aoyang Sha Huifang Yang Zhengyan He Zhigao Xu Chenjie wu Ming wu Ru'an Chi Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission&Hubei Key Laboratory of Catalysis and Materials ScienceCollege of Resources and Environmental ScienceSouth-Central Minzu UniversityWuhan430074China Key Laboratory for Green Chemical Process of Ministry of Education School of Resources&Safety EngineeringWuhan Institute of TechnologyWuhan 430073China

To solve the problems of the long development period,low mass transfer efficiency and high impurity conte nt in the in-situ leaching process of weathe red crust elution-deposited rare earth ores(WCE-DREO),cationic hydroxyethyl cellulose(PQ-10)was composited with conventional leaching agent ammonium sulfate((NH_(4))_(2)SO_(4))to form a novel composite leaching *** effects of PQ-10 concentration,leaching temperature and leaching flow rate of the composite leaching agent on the leaching kinetics and mass transfer processes of rare earth(RE)and aluminum(Al)were *** to the single leaching agent(NH_(4))_(2)SO_(4),the composite leaching agent(2 wt%(NH_(4))_(2)SO_(4)+0.02 wt%PQ-10)can reduce the RE leaching equilibrium time from 465 to 130 min and increase the RE leaching efficiency and decrease the Al leaching *** also facilitates the leaching process of WCE-DREO by increasing the peak concentrations of RE and Al,reducing the theoretical tower plate height(HETP)and improving the leaching mass transfer *** is indicated that PQ-10 can promote the leaching of *** leaching process of the composite leaching system conforms to the diffusion kinetic control *** the PQ-10 concentration is in the range of 0.005 wt%-0.020 wt%,the reaction orders of RE and Al are 0.73 and 0.54,respectively,which shows a positive effect on the leaching velocity;when the PQ-10 concentration is in the range of 0.030 wt%-0.060 wt%,the reaction orders of RE and Al are-1.16 and-0.75,respectively,which show a negative effect on the leaching *** the range of 10-50℃,the apparent activation energies of RE and Al are 15.02 and 17.31 kJ/mol,respectively,and the higher the leaching temperature,the smaller the HETP and the higher the leaching velocity and mass transfer *** increase in leaching flow rate contributes to the increase in the longitudinal diffusion velocity of the leaching agent within WCE-DREO,causing a shorter time for RE

关键词： Cationic hydroxyethyl cellulose Weathered crust elution-deposited rare earthores Leaching Novel compositeagent

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PltcRB:a practical distributed randomness beacon with optimal amortized communication complexity

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Science China(Information Sciences) 2025年第2期68卷 269-284页

作者： Zheyi wu Haolin LIU Lei WANG School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

The distributed randomness beacon(DRB) is a crucial tool for continuously generating unpredictable, bias-resistant,and publicly verifiable random numbers on a regular basis. This is particularly useful for applications such as lotteries, electronic voting, and cryptographic parameter generation. However, existing studies either require complex communication or rely on a public bulletin board to meet security requirements. This brings a performance bottleneck when dealing with a large number of participants. This paper introduces a novel DRB protocol PltcRB based on timed commitments, eliminating the need for a public bulletin board. Our approach achieves optimal communication complexity of O(n) while maintaining the desired properties of a DRB protocol. The computation complexity is also O(n) when n is larger than the security parameter κ. These results demonstrate the practicality and performance of PltcRB, supported by our experimental analysis under various configurations.

关键词： timed commitment randomness beacon random number optimal communication complexity permissionlessłinebreak setting

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Accelerated warming of High Mountain Asia predicted at multiple years ahead

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Science Bulletin 2025年第3期70卷 419-428页

作者： Shuai Hu Tianjun Zhou Bo wu Key Laboratory of Earth System Numerical Modeling and Application Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China

High-Mountain Asia(HMA)is an important source of freshwater since it holds the largest reservoir of frozen water outside the polar *** feeds ten great rivers,ultimately supporting more than 2 billion ***,the threat of accelerated glacier melt,which is a consequence of unprecedented global warming since the early 1950s,threatens water resources in the surrounding *** predictions of the near-term temperature change and synergistic mass loss of glaciers are essential but challenging to implement because of the impacts of internal climate ***,based on large ensembles of state-of-the-art decadal climate prediction experiments,we provide evidence that the internally generated surface air temperature variations in HMA can be predicted multiple years in advance,and the model initialization has robust added value to the decadal prediction ***-time decadal forecasts suggest that the HMA will experience accelerated warming in 2025-2032,where the surface warming will increase by 0.98°C(0.67 to 1.33°C;5%to 95%range)relative to the reference period 1991-2020,which is equivalent to 1.75 times the observed warming during *** decadal predictability originates from extratropical Pacific decadal variability modes,which modulate the convective heating in the tropical Pacific and influence HMA via the eastward-propagating atmospheric Kelvin *** warming in the coming decade will likely increase the shrinkage of the glacier volume over the HMA by 1.4%.This change poses unprecedented challenges,including potential water scarcity,ecosystem disruption,and increased risk of natural disasters,to HMA and surrounding regions.

关键词： Decadal prediction High Mountain Asia Surface air temperature Pacific decadal variabilities Glacier

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Quantum convolution inequalities on Frobenius von Neumann algebras

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Science China Mathematics 2025年第3期68卷 615-636页

作者： Linzhe Huang Zhengwei Liu Jinsong wu Beijing Institute of Mathematical Sciences and Applications Yau Mathematical Sciences Center and Department of Mathematics Tsinghua University

In this paper, we introduce Frobenius von Neumann algebras and study quantum convolution inequalities. In this framework, we unify quantum Young's inequality on quantum symmetries such as subfactors,and fusion bi-algebras studied in quantum Fourier analysis. Moreover, we prove quantum entropic convolution inequalities and characterize the extremizers in the subfactor case. We also prove quantum smooth entropic convolution inequalities. We obtain the positivity of comultiplications of subfactor planar algebras, which is stronger than the quantum Schur product theorem. All these inequalities provide analytic obstructions of unitary categorification of fusion rings stronger than the Schur product criterion.

关键词： Frobenius von Neumann algebra quantum Young's inequality quantum entropic convolution inequality unitary categorification

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基于混合神经网络和遗传算法的故障诊断系统

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现代电力 2005年第1期22卷 31-36页

作者：毕天姝倪以信吴复立周萃莘华北电力大学北京102206 香港大学黑龙江省齐齐哈尔市供电局黑龙江齐齐哈尔161000

故障诊断对于事故后快速恢复具有重要意义。多种人工智能技术在其中得以应用, 然而快速、准确的故障诊断仍是一个悬而未决的难题, 尤其在保护和断路器不正常动作或多重故障的情况下, 故障诊断更为困难。提出了一种基于神经网络 (ANN) ... 详细信息

故障诊断对于事故后快速恢复具有重要意义。多种人工智能技术在其中得以应用, 然而快速、准确的故障诊断仍是一个悬而未决的难题, 尤其在保护和断路器不正常动作或多重故障的情况下, 故障诊断更为困难。提出了一种基于神经网络 (ANN) 和遗传算法 (GA) 的故障诊断方法, 它采用三层前向神经网络执行诊断功能, 双重 GA循环优化该神经网络的结构和连接权重。第一重 GA循环用于优化神经网络结构, 第二重 GA循环进一步优化神经网络的连接权重。两重 GA循环可以搜索确定用于故障诊断的最优神经网络。有关的数学模型和算法流程在文中作了详细介绍。以4-母线简单电力系统为例, 进行了计算机仿真计算。结果表明, 基于混合神经网络和遗传算法的故障诊断系统优于传统的BP神经网络, 可以较好地解决故障诊断问题。

关键词：电力系统故障诊断人工神经网络遗传算法优化

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Mechanisms behind the surprising observation of supra-thermal ions in NIF’s fusion burning plasmas

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Science Bulletin 2025年第3期70卷 359-364页

作者： Yuhan Xue Dong wu Jie Zhang Key Laboratory for Laser Plasmas and Department of Physics and Astronomy Collaborative Innovation Center of IFSA(CICIFSA)Shanghai Jiao Tong UniversityShanghai 200240China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Although ignition had been achieved at the National Ignition Facility(NIF),recent observations of the experiments indicate novel physics that beyond theoretical predictions emerge,e.g.,the neutron analysis of experiments has revealed deviations from the Maxwellian distributions in ion relative kinetic energies of burning plasmas,with the surprising emergence of supra-thermal deuterium and tritium(DT)ions that fall outside the predictions of macroscopic statistical hydrodynamic *** our newly developed hybrid-particle-in-cell code,incorporating the newly-proposed model of large-angle collisions,we infer that that this could be attributed to the increased significance of large-angle collisions among DT ions andα-particles in the burning *** and unprecedented kinetic investigations into the implications of large-angle collisions in the burning plasma have yielded several key findings,including an ignition moment promotion by~10 ps,the presence of supra-thermal ions below an energy threshold,and approximately twice the expected deposition ofα-particles *** rationality of our findings is confirmed through the congruency between the neutron spectral moment analyses conducted by the NIF and our kinetic simulations,both highlighting progressively widening disparities between neutron spectral moment analyses and hydrodynamics predictions,which becomes more pronounced as the yield *** kinetic simulations with large-angle collisions not only provide novel insights for experiment interpretation but also open new research opportunities for the largely unexplored regime of the nuclear burning plasmas,which are distinguished by their exceptionally high energy densities and hold immense potential for illuminating the intricate physics that underpins the evolution of the early universe.

关键词： lon kinetics Supra-thermal ions Large-angle collisions Non-equilibrium ignition Inertial confinement fusion Burning plasmas

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3维颅骨表面模型的复杂孔洞修补

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中国图象图形学报 2013年第9期18卷 1156-1163页

作者：包佳蕊梁荣华吴福理黄鲜萍蒋莉陈矛浙江工业大学计算机科学与技术学院杭州310032

颅骨表面模型的孔洞复杂,很难用目前常用的图形学中某一类算法进行修补。目前基本修补算法(BHRA)可用来修补一般区域孔洞,但对于颅骨上破损较大复杂孔洞和特征区域复杂孔洞还没有较好的修补算法,为此提出一种颅骨模型复杂孔洞修补算法,... 详细信息

颅骨表面模型的孔洞复杂,很难用目前常用的图形学中某一类算法进行修补。目前基本修补算法(BHRA)可用来修补一般区域孔洞,但对于颅骨上破损较大复杂孔洞和特征区域复杂孔洞还没有较好的修补算法,为此提出一种颅骨模型复杂孔洞修补算法,该算法首先通过复杂孔洞的位置和复杂孔洞包围盒的面积来对该复杂孔洞进行分类,再选择相应的算法进行孔洞修补。针对颅骨上区域较大复杂孔洞,提出一种向内递归修补法(IRS),解决了传统孔洞修补方法修补曲面较为平坦的问题;针对颅骨上的特征区域复杂孔洞,提出了特征模型匹配法(TMA),使用标准模型作为约束并对其进行变形,使修补后的模型更符合人的面部特征。实验结果分析表明,该算法对颅骨上区域较大的复杂孔洞和特征区域孔洞的修补效果令人满意,同时将该修补后的颅骨模型进行颅面复原,颅面复原效果良好。

关键词：孔洞修补孔洞分类隐式曲面向内递归模型匹配

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Axial emission characteristics of an ionic liquid electrospray thruster with a circular emitter

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Chinese Journal of Aeronautics 2025年第1期38卷 297-305页

作者： Cheng YANG Jiawei LUO Xiangbei wu Yan SHEN School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China

Ionic Liquid Electrospray Thrusters(ILETs)are well suited for micro-nano satellite applications due to their small size,low power consumption,and high specific ***,the limited thrust of a single-emitter ILET restricts its use in space *** optimize the performance of ILETs and make them suitable for a wider range of space missions,we designed a Circular-emitter ILET(CILET)to convert a one-dimensional(point)emission into a twodimensional(line)*** CILET can self-organize multiple Taylor cones *** cones were photographed and the axial emission currents were measured under different voltage and pressure difference conditions with a CILET experimental *** emission can be divided into two stable states and one unstable state based on the flow and current *** current in Stable state Ⅰ increases non-linearly with the voltage,while that in Stable state Ⅱ is nearly linear with respect to the *** number of cones increases with the voltage in stable states,while the cones become short and crowded under high-voltage *** variation law of the number of cones can be explained with the self-organization *** variation in the current exhibits a good correlation with the number of *** study demonstrates the feasibility of circular emitters and experimentally indicates that the emission current is improved by approximately two orders of magnitude compared to that of a single capillary.

关键词： Electrospray Ionic liquid thruster Self-organize Emitter Taylor cone

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Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao wu Huayong CHEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou510640China University of Chinese Academy of Sciences Beijing100049China Department of Earth Sciences University of GenevaGeneva1205Switzerland Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou510640China

Porphyry copper deposits(PCDs)supply the majority of the world's copper(Cu)as well as significant amounts of molybdenum(Mo)and gold(Au).The formation of these deposits is controlled by a variety of geological factors,among which the magmatic oxidation is one of the focuses of current *** study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium(V)to scandium(Sc)and its correlation with the oxygen fugacity(fO2)of magmas from arcs of various crustal thicknesses *** compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic *** results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual ***,magnesium number(Mg#)at the onset of magnetite fractionation is strongly positively correlated with fO_(2)of the equilibrium *** on this,the oxidation of arc magmas from different crustal thicknesses can be *** result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust *** trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole,particularly in mature island and continental *** contrast,magmas in thinner arc crusts(<20 km),which are significantly influenced by subducted slab materials,display higher oxidation states than most of their thicker crust *** findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and,consequently,their capacity to generate *** oxidized,primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution,a process leading to copper *** the contrary,thick arcs where magnet

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

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Prediction of intrusive gas pores caused by resin burning in sand core for iron castings

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China Foundry 2025年第1期22卷 23-32页

作者： Ji-wu Wang Xiao-long Wang Yu-cheng Sun Yu-hang Huang Xiu-ming Chen Xiong-zhi wu Na Li Jin-wu Kang Tao Jing Tian-you Huang Hai-liang Yu School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Weichai Power Co. Ltd.Weifang 261061ShandongChina School of Mechanical Engineering Central South UniversityChangsha 41000China School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

In the production of castings,intrusive gas pore represents a kind of common defects which can lead to leakage in high gas-tightness requirement castings,such as cylinder blocks and cylinder heads for *** occurs due to the intrusion of gases generated during the resin burning of the sand core into castings during the casting ***,a gas generation and flow constitution model was established,in which the gas generation rate is a function of temperature and time,and the flow of gas is controlled by the gas release,conservation,and Darcy's *** heat transfer and gas flow during casting process was numerically *** dangerous point of cores is firstly identified by a virtual heat transfer method based on the similarity between heat transfer and gas flow in the sand *** gas pores in castings are predicted by the gas pressure,the viscosity and state of the melt for these dangerous *** distinct sand core structures were designed and used for the production of iron castings,and the simulated gas pore results were validated by the obtained castings.

关键词： gas pore numerical simulation iron casting sand core resin

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