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基于铀矿石浓缩物的稀土元素分布模式的产地溯源多元统计方法分析

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核化学与放射化学 2025年第1期47卷 78-85,I0004页

作者：占佳张海涛李志明徐江汪伟张伟超西北核技术研究院陕西西安710024

铀矿石浓缩物作为可以在国际上公开交易的核材料,其丰富的痕量杂质反映了铀矿石的形成、矿物组成、铀矿冶流程、产地等重要信息,是开展核取证分析的理想对象。铀矿石浓缩物的稀土元素分布模式作为重要特征指纹之一,可以作为有效的产地... 详细信息

铀矿石浓缩物作为可以在国际上公开交易的核材料,其丰富的痕量杂质反映了铀矿石的形成、矿物组成、铀矿冶流程、产地等重要信息,是开展核取证分析的理想对象。铀矿石浓缩物的稀土元素分布模式作为重要特征指纹之一,可以作为有效的产地溯源的工具。开展了主成分分析(PCA)、因子分析(FA)、聚类分析(CA)和偏最小二乘法(PLS)等方法对铀矿石浓缩物稀土元素分布模式的多元统计分析,尝试通过稀土元素分布模式进行铀矿石浓缩物的产地溯源研究。研究表明:各种不同的统计方法具有不同的优缺点,单靠一种或两种多元统计的方法不能够完全描述铀矿石浓缩物的特征指纹参数。对于类似于中国、澳大利亚或者加拿大等拥有巨大领土面积和复杂地质结构的国家,铀矿石浓缩物的产地溯源工作存在着很大的技术难度与风险,需要综合利用多种方法才能准确有效地进行产地溯源工作。

关键词：铀矿石浓缩物多元统计分析产地溯源核取证

Routing protocol for wireless quantum multi-hop mesh backbone network based on partially entangled GHZ state

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Frontiers of physics 2017年第4期12卷 187-196页

作者： Pei-Ying Xiong Xu-tao Yu Zai-Chen zhan. Hai-tao zhan.Jing-Yu Hua State Key Lab of Millimeter Waves Southeast University Nanjing 210096 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China College of Information Engineering Zhejiang University of Technology Hangzhou 310023 China

Quantum multi-hop teleportation is important in the field of quantum communication. In this study, we propose a quantum multi-hop communication model and a quantum routing protocol with multi- hop teleportation for wireless mesh backbone networks. Based on an analysis of quantum multi-hop protocols, a partially entangled Greenberger-Horne-Zeilinger （GHZ） state is selected as the quantum channel for the proposed protocol. Both quantum and classical wireless channels exist between two neighboring nodes along the route. With the proposed routing protocol, quantum information can be transmitted hop by hop from the source node to the destination node. Based on multi-hop telepor- tation based on the partially entangled GHZ state, a quantum route established with the minimum number of hops. The difference between our routing protocol and the classical one is that in the for- mer, the processes used to find a quantum route and establish quantum channel entanglement occur simultaneously. The Bell state measurement results of each hop are piggybacked to quantum route finding information. This method reduces the total number of packets and the magnitude of air inter- face delay. The deduction of the establishment of a quantum channel between source and destination is also presented here. The final success probability of quantum multi-hop teleportation in wireless mesh backbone networks was simulated and analyzed. Our research shows that quantum multi-hop teleportation in wireless mesh backbone networks through a partially entangled GHZ state is feasible.

关键词： wireless mesh backbone network multi-hop teleportation partially entangled GHZ state,quantum routing protocol

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物化之“善”:中国传统陶瓷造物中的器物观

陶瓷学报 2025年第1期46卷 204-210页

作者：詹伟彭雅喻宏景德镇陶瓷大学江西景德镇333403

中国传统陶瓷造物蕴藏着致用利人、重美轻用、器以藏礼的器物观,其本源特征与文化之多样性以隐喻的方式传递着“善”的造物伦理,它包含着中国传统造物哲学、工艺技术、审美风尚、制度礼仪等诸多内涵。从设计与文化的角度出发,以实用陶... 详细信息

中国传统陶瓷造物蕴藏着致用利人、重美轻用、器以藏礼的器物观,其本源特征与文化之多样性以隐喻的方式传递着“善”的造物伦理,它包含着中国传统造物哲学、工艺技术、审美风尚、制度礼仪等诸多内涵。从设计与文化的角度出发,以实用陶瓷、陈设陶瓷、陶瓷礼器三种品类之器为物质界定,探究“善”在不同器物品类观照之内的尺度范围。同时,结合当下可持续设计背景的发展趋势,对“善”之文化内涵与“器”的物性关系提出新的思考,以期为未来手工艺设计发展提供思路。

关键词：传统陶瓷造物器物观善

Can the Super-deduction of R&D Expenses BoostR&DInvestment?

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China & World Economy 2023年第5期31卷 135-160页

作者： tao Qian Yutao zhan.Shiyuan Pan China Academy of West Region Development Zhejiang UniversityChina School of Economics Zhejiang University and Research Center for Industries of the FutureWestlake UniversityChina School of Economics Zhejiang UniversityChina

The super-deduction of research and development(R&D)expenses is at the core of the policy to stimulate enterprise innovation in *** paper identifies whether firms are supported by the super-deduction policies for R&D expenses and uses the diferencein-diferences method to investigate the impact of the policies on R&D *** results show that changes in policy in 2013 significantly increased the R&D investment of firms engaging in key state-supported *** changes in 2016 significantly increased the R&D investment of firms engaging in non-key-state-supported *** not only invested all their tax incentives in R&D activities but also increased their investment in self-raised *** super-deduction policy had different impacts on different industries,firms with different boards,and firms with diferent *** policy significantly affected the manufacturing and construction industries,the Small and Medium Enterprise Board,and non-state-owned *** a mechanism analysis,we found that the policy significantly reduced the user cost of R&D and increased the net cash flow of enterprises,which could raise a firm's R&D *** is necessary to increase policy support,expand the scope of super-deductible expenses,and increase the super-deduction rate based on industry classification according to the sensitivity of different industries to the policy.

关键词： R&D investment super-deduction policy for R&D expenses tax incentives

Oxide coating mechanism during fluidized bed reduction: solid-state reaction characteristics between iron ore particles and MgO

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1019-1028页

作者： Lei Guo Jin-tao Gao Yi-wei Zhong Han Gao zhan.cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Experiments on the solid-state reaction between iron ore particles and MgO were performed to investigate the coating mechanism of MgO on the iron ore particles＇ surface during fluidized bed reduction. MgO powders and iron ore particles were mixed and compressed into briquettes and, subsequently, roasted at different temperatures and for different time periods. A Mg-containing layer was observed on the outer edge of the iron ore particles when the roasting temperature was greater than 1173 K. The concentration of Fe in the Mg-containing layer was evenly distributed and was approximately 10wt%, regardless of the temperature change. Boundary layers of Mg and Fe were observed outside of the iron ore particles. The change in concentration of Fe in the boundary layers was simulated using a gas–solid diffusion model, and the diffusion coefficients of Fe and Mg in these layers at different temperatures were calculated. The diffusion activation energies of Fe and Mg in the boundary layers in these experiments were evaluated to be approximately 176 and 172 k J/mol, respectively.

关键词： fluidized beds coating solid reaction ferric oxide magnesia diffusion coefficient

Compound fuzzy model for thermal performance of refrigeration compressors

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Chinese Science Bulletin 2000年第14期45卷 1319-1322页

作者： Guoliang Ding Chunlu zhan. tao zhan.Hao Li Shanghai Jiao Tong Univ Inst Refrigerat & Cryogen Engn Shanghai 200030 Peoples R China

The fuzzy method is introduced to the calculation of thermal performance of refrigeration compressors. A compound model combining classical thermodynamic theory and fuzzy theory is presented and compared with a simple fuzzy model without classical thermodynamic fundamentals. Case study of refrigeration compressors shows that the compound fuzzy model and the simple fuzzy model are both more efficient than the classical thermodynamic method. However, the compound fuzzy model is of better precision and adaptability.

关键词： refrigeration compressor thermal performance fuzzy theory.

A facile method to synthesize water-soluble Pd8 nanoclusters unraveling the catalytic mechanism of p-nitrophenol to p-aminophenol

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Nano Research 2019年第10期12卷 2589-2596页

作者： Pan An Rajini Anumula Chaonan Cui Yang Liu Fei zhan.Ye tao Zhixun Luo Beijing National Laboratory for Molecular Sciences(BNLMS)and State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Hydroge nation of p-n itrophe nol(PNP)towards the con versi on to p-ami nophe no I(PAP)by metal catalysis is known as a simple and I eco-frie ndly tech nique for the production of corresp on ding in dustrial and pharmaceutical in *** continu ous efforts are paid for§more sustainable and greener procedures by using transition metal catalysts,atomic-precise reaction mechanism for the PNP-to-PAP is still illusive to be fully un *** ng a dry-wet com bined strategy,here we have syn thesized water-soluble Pd8 nano clusters(NCs)with mercaptosuccinic acid(H2SMA)as the ligand,and the Pd8 NCs found high catalytic performance for the conversion of PNP-to-PAP,as identified by the electrospray ionization mass spectrometer(ESI-MS)*** gradual changes over time of ultraviolet-visible(UV-vis)spectra of PNP really display the catalytic reduction by NaBH4 in presence of Pd8 ***,in-depth charge transfer interactions between PNP and the Pd8 clusters at the proton-rich conditions are investigated by natural bond orbital(NBO)analysis and electron density differenee(EDD)*** exothermic and kinetic-favorable reaction pathways are addressed,based on successive PNP hydrogenation and H2O removal processes,clarifying the reaction mechanism of Pd *** is worth noting that this solid-state synthetic route for such Pd8 clusters enables gram-scale quantity of production in likely practical use.

关键词： catalytic clusters mechanism

Influence of hydrogen concentration on Fe_2O_3 particle reduction in fluidized beds under constant drag force

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 12-20页

作者： Lei Guo Han Gao Jin-tao Yu Zong-liang zhan. zhan.cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The fixed-gas drag force from a model calculation method that stabilizes the agitation capabilities of different gas ratios was used to explore the influence of temperature and hydrogen concentration on fluidizing duration, metallization ratio, utilization rate of reduction gas, and sticking behavior. Different hydrogen concentrations from 5vol%to 100vol%at 1073 and 1273 K were used while the drag force with the flow of N2 and H2 （N2：2 L·min^-1;H2：2 L·min^-1） at 1073 K was chosen as the standard drag force. The metallization ratio, mean reduc-tion rate, and utilization rate of reduction gas were observed to generally increase with increasing hydrogen concentration. Faster reduction rates and higher metallization ratios were obtained when the reduction temperature decreased from 1273 to 1073 K. A numerical relation among particle diameter, particle drag force, and fluidization state was plotted in a diagram by this model.

关键词： fluidized beds ferric oxide iron ores agglomeration hydrogen drag force

A reporter for noninvasively monitoring gene expression and plant transformation

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Horticulture Research 2020年第1期7卷 821-826页

作者： Yubing He tao zhan. Hui Sun Huadong zhan.Yunde Zhao State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural UniversityNanjing 210095China National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research(Wuhan) Huazhong Agricultural UniversityWuhan 430070China Section of Cell and Developmental Biology University of California San Diego9500 Gilman DriveLa JollaCA 92093-0116USA Tata Institute for Genetics and Society-UCSD La JollaCA 92093-0335USA

Reporters have been widely used to visualize gene expression,protein localization,and other cellular activities,but the commonly used reporters require special equipment,expensive chemicals,or invasive ***,we construct a new reporter RUBY that converts tyrosine to vividly red betalain,which is clearly visible to naked eyes without the need of using special equipment or chemical *** show that RUBY can be used to noninvasively monitor gene expression in ***,we show that RUBY is an effective selection marker for transformation events in both rice and *** new reporter will be especially useful for monitoring cellular activities in large crop plants such as a fruit tree under field conditions and for observing transformation and gene expression in tissue culture under sterile conditions.

关键词： transformation reporter sterile