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Progress in Natural Science:Materials International 2016年第6期26卷 600-612页

作者： fei Zhong fei fan Shusuo Li Jiangbo Sha School of Materials Science and Engineering Beihang University

In this work,2at% Mo,2at% Nb and 2at% Hf were substituted for the same amount of W into a Co-9Al-9W-2Ta-0.02 B alloy（hereafter referred as to 2Mo, 2Nb and 2Hf alloys, respectively, while the original alloy is denoted as 0Me alloy）. The effect of the Mo, Hf and Nb additions on the isothermal oxidation resistance, oxide scale evolution and failure mechanism, of the Co-9Al-9W-2Ta-0.02 B alloy when exposed at 800 °C and 900 °C for 100 h was investigated. It was found the Mo, Hf and Nb additions degraded the oxidation resistance of the Co-9Al-9W-2Ta-0.02 B alloy, while the 2Mo alloy always displayed the poorest oxidation resistance, resulted from heavy spallation of the oxide scale. An oxide scale composed of an outer Co3O4+CoO layer, a middle complex oxide layer enriched with Al, W and Ta, and a γ/needle-like Co3W zone adhering to the γ/γ' substrate was gradually formed; moreover, a continuous or discontinuous Al2O3layer and dispersive Al2O3dots or slices were observed within the γ/needle-like Co3W zone, depending on the oxidation temperature and added elements（Mo, Hf and Nb）. The formation of volatile MoO3in the oxide scale of the 2Mo alloy enhance the exfoliation of the oxide products, resulting in severe spallation and poor oxidation resistance.

关键词： Co-Al-W based superalloys Mo,Nb,Hf alloying Oxidation behaviour Oxide scale spallation

Bounded Evaluation:Querying Big Data with Bounded Resources

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International Journal of Automation and computing 2020年第4期17卷 502-526页

作者： Yang Cao Wen-fei fan Teng-fei Yuan University of Edinburgh Edinburg EH89ABUKUniversity of EdinburghEdinburg EH89ABUK Shenzhen Institute of Computing Sciences Shenzhen UniversityShenzhen 518060China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing 100191China

This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exists a fraction DQ of D such that Q(D)=Q(DQ),and the cost of identifying DQ is independent of the size of *** has been shown that with an auxiliary structure known as access schema,many queries in relational algebra(RA)are boundedly evaluable under the set semantics of *** paper extends the theory of bounded evaluation to RAaggr,i.e.,RA extended with aggregation,under the bag semantics.(1)We extend access schema to bag access schema,to help us identify DQ for RAaggr queries Q.(2)While it is undecidable to determine whether an RAaggr query is boundedly evaluable under a bag access schema,we identify special cases that are decidable and practical.(3)In addition,we develop an effective syntax for bounded RAaggr queries,i.e.,a core subclass of boundedly evaluable RAaggr queries without sacrificing their expressive power.(4)Based on the effective syntax,we provide efficient algorithms to check the bounded evaluability of RAaggr queries and to generate query plans for bounded RAaggr queries.(5)As proof of concept,we extend PostgreSQL to support bounded *** experimentally verify that the extended system improves performance by orders of magnitude.

关键词： Bounded evaluation resource-bounded query processing effective syntax access schema boundedness

Extant primates and development of primatology in China: Publications, student training, and funding

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Zoological Research 2018年第4期39卷 249-254页

作者： Peng-fei fan Chi Ma School of Life Sciences Sun Yat-Sen University

China supports the richest non-human primate diversity in the northern hemisphere, providing an excellent opportunity for Chinese primatologists to take a leading role in advancing the study of primatology Primatology in China began to flourish after 1979. To date, Chinese primatologists have published more than 1 000 papers in journals indexed by the Chinese Science Citation Database and the Web of Science Core Collection, and universities and academic institutions have trained 107 PhD students and 370 Masters students between 1984 and 2016. In total, the National Science Foundation of China has funded 129 primate projects （RMB 71.7 million） supporting 59 researchers from 28 organizations. However, previous research has also shown obvious species bias. Rhinopithecus roxellana, Rhinopithecus bieti, and Macaca mulatta have received much greater research attention than other species. Researchers have also tended to continue to study the same species （55.2%） they studied during their PhD training. To promote the development of primatology in China, we suggest （1） the need for a comprehensive primatology textbook written in Chinese, （2） continued training of more PhD students, and （3） encouragement to study less well-known primate species.

关键词： Gibbon Snub-nosed monkey Leafmonkey Macaque Slow Iories

Promoting effect of super absorbent polymer on hydrate formation

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Journal of Natural Gas Chemistry 2010年第3期19卷 251-254页

作者： fei Long Shuanshi fan Yanhong Wang Xuemei Lang The Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of Education School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 Guangdong China

The effect of super absorbent polymer（SAP） on the formation of tetrahydrofuran（THF） hydrate was studied by the successional cooling *** was found that THF solution samples with 0.004 wt% and 0.03 wt% of SAP formed THF hydrate completely during the same cooling *** corresponding induction time was 16-29 min,14-31 min,respectively,which was obviously shorter than that of THF solution samples without SAP（25-62 min）.It indicated that SAP accelerated the formation of THF *** the same time,the pictures of hydrate formation with and without SAP had been *** was found that SAP did not change the morphology of the ***,the mechanism of SAP promoting effect on the formation of THF hydrate was suggested.

关键词： super absorbent polymer tetrahydrofuran hydrate promoting effect

基于碳排放核算范围视角下城市社区实现绿色繁荣的规划策略行动

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国土与自然资源研究 2025年第1期 55-59页

作者：费凡肖越李晓晖广州市城市规划勘测设计研究院广州510060 广州市资源规划和海洋科技协同创新中心广州510060 广东省城市感知与监测预警企业重点实验室广州510060

社区作为现代城市管理和社会生活的重要基础单元,是碳排放的重点也是低碳发展的重要载体。在梳理“绿色繁荣”社区的目标与内涵基础上,结合相关技术标准与理论实践,以碳排放核算的视角进行切入,将国际碳排放核算标准中的“范围”概念应... 详细信息

社区作为现代城市管理和社会生活的重要基础单元,是碳排放的重点也是低碳发展的重要载体。在梳理“绿色繁荣”社区的目标与内涵基础上,结合相关技术标准与理论实践,以碳排放核算的视角进行切入,将国际碳排放核算标准中的“范围”概念应用到社区层面,建立社区碳排放的范围分类,识别社区减碳的关键维度,并提出实现绿色繁荣社区的规划设计策略与具体行动,研究结果可为城市、区域乃至国家实现低碳高质量发展目标提供经验借鉴。

关键词：碳排放核算绿色繁荣低碳社区碳排放范围规划策略

Transcriptomic Profiling of the Immune Response to Crowding Stress in Juvenile Turbot (Scophthalmus maximus)

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Journal of Ocean University of China 2020年第4期19卷 911-922页

作者： HUO Huanhuan GAO Xiaoqiang fei fan QIN fei HUANG Bin LIU Baoliang Key Laboratory of Sustainable Development of Marine Fisheries of Ministry of Agriculture Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdao 266071China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China College of Animal Science and Technology Jiangxi Agricultural UniversityNanchang 330045China

In this study,juvenile turbot Scophthalmus maximus were vaccinated with attenuated Edwardsiella tarda(EIBAV1)and reared at two different densities,low density(LD),(5.25±0.02)kg m−2,as control group and high density(HD),(20.53±0.05)kg m−2,as experimental *** density was considered as the *** weeks after vaccination,the transcriptomes of spleen and head kidney from the turbot in two groups were analyzed with RNA-Seq technology.A total of 447 million reads were assembled into 41136 genes with an average length of 1274 bp and a N50 size of 2295 bp.A comparison of gene expression between HD and LD groups revealed 1155 differentially expressed genes(DEGs).Enrichment and pathway analysis of the 10 immune-related DEGs showed the centrality of toll-like receptor signaling pathway,cytosolic DNA-sensing pathway and platelet activation in the host immune *** 5 overexpressed inflammatory cytokines and 5 downregulated signal-regulated cytokines genes are covered by these immune-related *** was inferred that cells suffer damage and the immune response is restrained in turbot under crowding stress.

关键词： turbot transcriptome crowding stress immune response

Combinatorial Optimization of Ba/Fe-cordierite Solid Solution （Ba0.05Fe0.1Mg）2Al4Si5O18 for High Infrared Radiance Materials

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Chinese Journal of Chemical Physics 2012年第3期25卷 345-351,374页

作者： Fu-han Tang Jian-dong Zhuang fan fei Qian Liu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences ShanEhai 200050 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A combinatorial chemistry method was employed to screen the Ba2＋ and Fe3＋ incorporated into cordierite structure （Ba0.05Fe0.1Mg）2A14Si5018 for exploring of high infrared radiance materials. A series of square-type sample array that consists of 7×7 compositions was syn- thesized by ink-jetting nitrate solutions into micro-reactor wells in a ceramic plate and then heat-treated at high temperatures. X-ray diffraction and infrared thermograph were used to analyze the effects of Ba2＋/Fe3＋ incorporating on the lattice distortion of cordierite and resultant changes in infrared radiance properties. Based on the results of X-ray phase analy- sis and radiance measurement of the scale-up prepared samples, the optimal Ba2＋ and Fe3＋ co-adding amount was determined to be 5%Ba2＋ plus 10%Fe3＋. Moreover, the infrared emissivity of the optimal composition at 100 ℃ was found to be higher than 0.8 in a wide wavelength range of 5-24μm. The research work demonstrates a promising application of Ba2＋/Fe3＋ cordierite solid solution as a kind of infrared heating materials for energy saving.

关键词： Cordierite Solid solution Combinatorial ink-jetting solution Infrared radiance enhancement

Model experiment of rock blasting with single borehole and double free-surface

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Mining Science and Technology 2009年第3期19卷 395-398,404页

作者： TIAN Jian-sheng QU fan-fei State Key Laboratory for Geomechanics ＆ Deep Underground Engineering Xuzhou Jiangsu 221008 China School of Architecture ＆ Civil Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China 11th Coal Mine of Pingdingshan Coal Co. Ltd Pingdingshan Henan 467000 China

In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-surface was performed with the objective of studying the effect of parameters such as charge structure, free-surface and rock compressive strength on rock *** model experiments indicate that:1) the smaller the rock compressive strength and density, the more distinctive the cavity expanding action by blasting;2) the powder factor in an air-decoupling charge structure is larger than that in a coupling charge structure, i.e., the explosive energy in an air-decoupling charge structure transferred to the rocks is less than that in a coupling charge structure;3) a free-surface improves the utilizations of explosive energy;4) an air-decoupling charge structure helps to maintain the integrity and stability of wall rock in controlled perimeter blasting, such as in roadways and tunnel excavation by drilling and blasting.

关键词： model experiment single borehole cylindrical charge air-decoupling charge structure free surface

Entropy squeezing for three-level atom interacting with a single-mode field

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Chinese Physics B 2019年第6期28卷 81-86页

作者： fei-fan Liu Mao-Fa fang Xiong Xu Synergetic Innovation Center for Quantum Effects and Application Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of EducationSchool of Physics and ElectronicsHunan Normal UniversityChangsha 410081China

The entropy squeezing for a three-level atom interacting with a single-model field is studied. A general definition of entropy squeezing for three-level atom is given according to entropic uncertainty relation of three-level system, and the calculation formalism of entropy is derived for a cascade three-level atom. By using numerical calculation, the entropy squeezing properties of a cascade three-level atom are examined. Our results show that, three-level atom can generate obvious entropy squeezing effect via choosing appropriate superposition state of three-level atom. Our results are meaningful for preparing three-level system information resources with ultra-low quantum noise.

关键词： variance squeezing entropy squeezing three-level atom

Species bias and spillover effects in scientific research on Carnivora in China

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Zoological Research 2021年第3期42卷 354-361页

作者： Zhi-Ning Wang Li Yang Peng-fei fan Lu Zhang School of Life Sciences Sun Yat-Sen UniversityGuangzhouGuangdong 510275China

Scientific research provides essential information for conservation of threatened *** deficiency due to insufficient research impedes the design of conservation plans,and research bias may mistakenly direct limited resources to low biodiversity regions or less threatened ***,we conducted a systematic review of published papers,grants,and graduate student training on carnivorans in China to identify species bias and research ***,we collected intrinsic and extrinsic features of carnivorans,and identified features that impact research intensity using generalized linear *** found that the amount of research on carnivorans increased markedly after 2000,but species bias *** and big cats received the greatest research attention,while most small-and medium-sized carnivorans received little attention,thus showing the 80-20 *** with a higher level of endemism and protection under Chinese law received more *** an animal conservation icon in China,the giant panda(Ailuropoda melanoleuca)attracted more than 50%of overall carnivoran research ***,the giant panda also showed spillover effects,i.e.,post-doctoral graduates who studied the giant panda shifted their research focus to other species after graduation,which may help improve research on other ***,to improve and strengthen Carnivora research and conservation,we suggest investing greater effort in species of less concern,training of more graduate students,and reinforcing academic *** such actions are not taken,many carnivoran species will continue being data deficient and threatened.

关键词： Ailuropoda melanoleuca Carnivora Conservation Research bias 80-20 phenomenon