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Acta Geologica Sinica(English Edition) 2010年第2期84卷 257-268页

作者： ZHANG Yi WANG Jun liu lujun LI Nan Paleontological Institute of Shenyang Normal University Shenyang 110034 China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Shenzhen Fair Lake Botanical Garden Shenzhen 518004 China

A new species of gymnospermous fossil wood, Protophyllocladoxylon jingyuanense sp. nov., is described from the lower part of the Tsingyuan Formation （Serpukhovian/Late Mississippian）, near the coal mine of Ciyao, Gansu, northwestern China. The specimen is preserved only in silicified secondary xylem, while growth rings are absent. Pits in radial tracheidal walls are araucaroid in type, uniseriate, occasionally biseriate. Xylem rays are homogeneous, uniseriate, occasionally biseriate. Cross-field pits are simple, large, one to two in number. Axial parenchyma is absent. The anatomical characters and geographic distribution of Protophyllocladoxylon woods through geological ages are documented. Those species with axial parenchyma and without growth rings live in warm climate, whereas the species without axial parenchyma and with growth rings are present either in warm or cool climate. The ideal living climate for Protophyllocladoxylon woods is warm and wet. Our new species, as a fossil wood of Early Carboniferous, is likely the earliest known species of Protophyllocladoxylon.

关键词： Protophyllocladoxylonjingyuanense growth rings axial parenchyma climate,

Recent Advances on Non-Marine Late Paleozoic Strata and Floras： Outcome of the 16th International Congress on the Carboniferous and Permian

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Episodes 2008年第3期31卷 348-350页

作者： Wang, Jun liu, lujun Pfefferkorn, Herman W. Chinese Acad Sci LPS Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China Univ Penn Dept Earth & Environm Sci Philadelphia PA 19104 USA

The 16th International Congress on the Carboniferous and Permian （ICCP XVI） orga- nized by the Nanjing Institute of Geology and Palaeontology under the Chinese Acad- emy of Sciences, the Institute of Geology under the Chinese Academy of Geological Sciences, the China University of Geo- sciences and the Nanjing University took place in Nanjing, June 21-24, 2007. More than 150 colleagues from over 20 countries attended the quadrennial conference.

关键词：古生代植物学石炭纪二叠纪项目研究

Part-Whole Relational Few-Shot 3D Point Cloud Semantic Segmentation

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Computers, Materials & Continua 2024年第3期78卷 3021-3039页

作者： Shoukun Xu lujun Zhang Guangqi Jiang Yining Hua Yi liu School of Computer Science and Artificial Intelligence Aliyun School of Big Data and School of SoftwareChangzhou UniversityChangzhou213164China Department of Computer Science University of AberdeenKing’s CollegeAberdeenAB243FXUK

This paper focuses on the task of few-shot 3D point cloud semantic *** some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation and inaccurate semantic *** tackle these issues,we first leverage part-whole relationships into the task of 3D point cloud semantic segmentation to capture semantic integrity,which is empowered by the dynamic capsule routing with the module of 3D Capsule Networks(CapsNets)in the embedding ***,the dynamic routing amalgamates geometric information of the 3D point cloud data to construct higher-level feature representations,which capture the relationships between object parts and their ***,we designed a multi-prototype enhancement module to enhance the prototype ***,the single-prototype enhancement mechanism is expanded to the multi-prototype enhancement version for capturing rich ***,the shot-correlation within the category is calculated via the interaction of different samples to enhance the intra-category *** studies prove that the involved part-whole relations and proposed multi-prototype enhancement module help to achieve complete object segmentation and improve semantic ***,under the integration of these two modules,quantitative and qualitative experiments on two public benchmarks,including S3DIS and ScanNet,indicate the superior performance of the proposed framework on the task of 3D point cloud semantic segmentation,compared to some state-of-the-art methods.

关键词： Few-shot point cloud semantic segmentation CapsNets

磁粉粒径对烧结Nd-Fe-B磁性能和初始磁导率的影响

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稀有金属材料与工程 2019年第2期48卷 668-672页

作者：刘路军刘政江西理工大学江西赣州341000

采用粉末冶金法制备了名义成分为(Pr_(25)Nd_(75))_(25)Dy_6Al_(0.5)B_1Co_1Cu_(0.2)Fe_(bal)的烧结Nd-Fe-B磁体,并研究了不同粒径磁粉制备的烧结Nd-Fe-B磁体磁性能和初始磁化阶段最大磁导率的相应演变规律。结果表明,磁粉平均尺寸为3.0... 详细信息

采用粉末冶金法制备了名义成分为(Pr_(25)Nd_(75))_(25)Dy_6Al_(0.5)B_1Co_1Cu_(0.2)Fe_(bal)的烧结Nd-Fe-B磁体,并研究了不同粒径磁粉制备的烧结Nd-Fe-B磁体磁性能和初始磁化阶段最大磁导率的相应演变规律。结果表明,磁粉平均尺寸为3.0μm时对应的磁体的内禀矫顽力最大,磁粉平均尺寸为3.5μm时对应的磁体的剩磁最高。从磁体的微观结构观察和性能测试发现,磁粉粒径为3.0μm时,烧结磁体主相更加规则、均匀,提高了磁体的矫顽力。随着磁粉平均尺寸进一步减小,磁粉粒径为2.5μm时,富Nd相以氧化物形式发生了团聚,且分布不均匀,磁体晶界出现孔洞,去磁耦合效率下降,导致磁体矫顽力降低;磁体氧含量随着磁粉平均尺寸的减小而增大,磁体内杂质相增多,剩磁下降;增多的杂质相使得磁化初始阶段的最大磁导率降低。

关键词：烧结Nd-Fe-B 磁性能最大磁导率磁粉粒径

Magnesium doping to improve the light to heat conversion of OMS-2 for formaldehyde oxidation under visible light irradiation

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Chinese Chemical Letters 2024年第4期35卷 193-198页

作者： Tingting liu Pengfei Sun Wei Zhao Yingshuang Li lujun Cheng Jiahai Fan Xiaohui Bi Xiaoping Dong College of Chemistry and Chemical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China College of Environmental Science and Engineering Nankai UniversityTianjin 300071China Hangzhou Kaiming Catalyst Co. Ltd.Hangzhou 310013China

Mg-doped manganese oxide octahedral molecular sieve(Mg-OMS-2)catalysts were prepared by hydrothermal *** photothermal degradation performance of these catalysts for formaldehyde(HCHO)in batch system and continuous system was *** light absorption of OMS-2 was increased by Mg-doped,especially for near infrared light,which promoted surface temperature reach a maximum of 214.8℃ under xenon *** this temperature,the reinforced surface lattice oxygen and oxygen vacancy that formed by lattice distortion via Mg-doped were *** best HCHO elimination efficiency was achieved over Mg_(0.2)/OMS-2 catalyst with Mg^(2+)/Mn^(2+)=1/5,which could reduce HCHO from 250 ppm to 10 ppm within 20 *** in situ DRIFTS was also carried out to monitor the changes in the content of reaction intermediates and analyze the degradation paths of *** was found the HCHO was attacked by formed·OH and·O^(2-) to generate formate species and carbonate species,and finally transformed to CO_(2) and H_(2)*** photothermal catalytic oxidation process exhibited a high efficiency purification of HCHO without the help of extra energy consumption.

关键词： Mg doping Photothermal catalysis OMS-2 HCHO Reaction mechanism

Optimized Selection Method of Air Combat Course of Action under Stochastic Uncertainty

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 494-518页

作者： Yun Zhong Jieyong Zhang Peng Sun lujun Wan Kepeng Wang Information and Navigation College Air Force Engineering UniversityXi’an710077China Equipment Management and Unmanned Aerial Vehicle Engineering College Air Force Engineering UniversityXi’an710051China Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710051China Unit 94040 of PLA Korla841000China

Aiming at the design problem of aviation swarm combat course of action(COA),considering the influence of stochastic parameters in the causal relationship model and optimization problem model,according to the dynamic influence net(DIN)theory,stochastic simulation technique,feedforward neural network(FNN)function approximation technique and multi-objective artificial fish school algorithm(MOAFSA),this paper proposed a COA optimized method based on DIN and multi-objective stochastic chance constraint optimization for aviation swarm ***,on the basis of establishing the overall framework of the model and defining the elements of causal relationship modeling,the static and dynamic causal relationship modeling and optimization problem modeling were carried out ***,the probability propagation mechanism of DIN was established,which mainly included two aspects,i.e.,the overall process and the specific ***,input and output data were generated based on stochastic *** to these data,FNN was adopted for function approximation,and MOAFSA was adopted for iterative ***,the rationality of the model,and the effectiveness and superiority of the algorithm were verified through multiple sets of simulation cases.

关键词： Stochastic uncertainty aviation swarm stochastic simulation course of action feedforward neural network multi-objective artificial fish school algorithm

Nd_(90)Al_(10)晶界调控对晶界扩散磁体磁性能和微观结构的影响

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金属学报 2023年第11期59卷 1457-1465页

作者：刘路军刘政刘仁辉刘永江西理工大学材料与冶金学部赣州341000 江西理工大学机电工程学院赣州341000 江西理工大学江西省稀土磁性材料及器件重点实验室赣州341000

采用添加Nd_(90)Al_(10)低熔点合金调控制备了扩散用烧结Nd_2Fe_(14)B磁体,并采用Tb晶界扩散制备了相应的扩散磁体,分析了扩散磁体的晶界结构和成分对磁体矫顽力的影响。结果表明,添加质量分数为0.5%的Nd_(90)Al_(10)合金调控后,晶界扩... 详细信息

采用添加Nd_(90)Al_(10)低熔点合金调控制备了扩散用烧结Nd_2Fe_(14)B磁体,并采用Tb晶界扩散制备了相应的扩散磁体,分析了扩散磁体的晶界结构和成分对磁体矫顽力的影响。结果表明,添加质量分数为0.5%的Nd_(90)Al_(10)合金调控后,晶界扩散(GBD)后磁体的矫顽力提高到1439 kA/m,相对于未晶界调控的扩散磁体增加了530 kA/m。添加Nd_(90)Al_(10)低熔点合金不会影响GBD前磁体的Curie温度,但降低了磁体的低温相变温度。GBD后磁体Tb取代晶格中的Nd引起Nd_2Fe_(14)B相的晶格常数减小,从而使XRD谱中衍射峰位右移。经Nd_(90)Al_(10)调控后的扩散磁体表面处的主相晶粒的富Tb壳清晰可见。从距离磁体表面20μm增加到100μm时,富Tb壳层仍清晰可见。当深度继续增加到500μm时,经Nd_(90)Al_(10)调控后的扩散磁体晶粒周围都有连续晶界相。经晶界调控的扩散磁体可见衬度明显的富Tb壳层,形成了非晶的富Nd相,增强了两两主相晶粒间的去磁耦合能力。Nd在富Nd相中心区域出现峰值,更多的富Nd相在晶界扩散过程中作为Tb向磁体内扩散的通道,Tb原子在富Nd相的浓度高达约35%,其扩散深度和使用效率明显提升。

关键词：烧结钕铁硼晶界扩散磁性能晶界调控

Interconnected microstructure and flexural behavior of Ti_(2)C-Ti composites with superior Young’s modulus

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2088-2101页

作者： Fengbo Sun Rui Zhang Fanchao Meng Shuai Wang lujun Huang Lin Geng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Waikato Centre for Advanced Materials and Manufacturing School of EngineeringUniversity of WaikatoHamilton 3240New Zealand State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001China

To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman *** to the results,the in-situ reaction yielded an interconnected microstructure composed of Ti_(2)C particles when the Ti_(2)C content reached 50vol%.With widths of 10 and 230 nm,the intraparticle Ti lamellae in the prepared composite exhibited a bimodal size distribution due to precipitation and the unreacted Ti phase within the grown Ti_(2)C *** composites with interconnected microstructure attained superior properties,including E of 174.3 GPa and ultimate flexural strength of 1014 *** with that of pure Ti,the E of the composite was increased by 55% due to the high Ti_(2)C content and interconnected *** outstanding strength resulted from the strong interfacial bonding,load-bearing capacity of interconnected Ti_(2)C particles,and bimodal intraparticle Ti lamellae,which minimized the average crack driving *** flexural tests revealed preferential crack initiation along the{001}cleavage plane and grain boundary of Ti_(2)C in the region with the highest tensile *** addition,the propagation can be efficiently inhibited by interparticle Ti grains,which prevented the brittle fracture of the composites.

关键词： titanium matrix composites titanium carbide interface Young’s modulus flexural behavior

The Temperature Intelligence Control System Based on Single Chip-Microprocessor

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微计算机信息 2003年第7期19卷 31-32页

作者： (changchun Institute of Technology ,changchun 130012) liu, Shurong Ding,lujun changchun Institute of Technology changchun 130012

The paper introduces a temperature control systembased on AT89C51 single-chip-microprocessor, and discussesthe principle , hardware structure, and software design of thissystem in detail.

关键词：单片机温度智能控制系统 AT89C51 软件设计硬件设计

Conservation genomics provides insights into genetic resilience and adaptation of the endangered Chinese hazelnut, Corylus chinensis

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Plant Diversity 2024年第3期46卷 294-308页

作者： Zhen Yang Lisong Liang Weibo Xiang lujun Wang Qinghua Ma Zhaoshan Wang Key Laboratory of Tree Breeding and Cultivation National Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091China National Engineering Research Center of Eco-Environment Protection for Yangtze River Economic Belt China Three Gorges CorporationBeijing 100083China Rare Plants Research Institute of Yangtze River China Three Gorges CorporationYichang 443133China Research Institute of Economic Forest Cultivation and Processing Anhui Academy of ForestryHefei 230031China

Global climate change has increased concerns regarding biodiversity ***,many key conservation issues still required further research,including demographic history,deleterious mutation load,adaptive evolution,and putative *** we generated the first chromosome-level genome of the endangered Chinese hazelnut,Corylus chinensis,and compared the genomic signatures with its sympatric widespread ***-C yunnanensis *** found large genome rearrangements across all Corylus species and identified species-specific expanded gene families that may be involved in *** genomics revealed that both *** and the *** complex had diverged into two genetic lineages,forming a consistent pattern of southwestern-northern *** size of the narrow southwestern lineages of both species have decreased continuously since the late Miocene,whereas the widespread northern lineages have remained stable(***) or have even recovered from population bottlenecks(*** complex) during the *** with ***-C. yunnanensis complex,*** showed significantly lower genomic diversity and higher inbreeding ***,*** carried significantly fewer deleterious mutations than ***-C. yunnanensis complex,as more effective purging selection reduced the accumulation of homozygous *** also detected signals of positive selection and adaptive introgression in different lineages,which facilitated the accumulation of favorable variants and formation of local ***,both types of selection and exogenous introgression could have mitigated inbreeding and facilitated survival and persistence of ***,our study provides critical insights into lineage differentiation,local adaptation,and the potential for future recovery of endangered trees.

关键词： Conservation genomics Demographic history Inbreeding Genetic load Runs of homozygosity Local adaptation