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Advances.in Manufacturing 2024年第1期12卷 94-107页

作者： yan Liu Qiu Tang Xin-Cheng Tian school of Control s.ience and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of intelligent Unmanned system Ministry of EducationJinan250061People’s Republic of China school of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes.is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteris.ics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establis.ing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Risk factors for lymph node metastasis.in superficial esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2024年第13期30卷 1810-1814页

作者： yan-Bo Yu Department of Gastroenterology Laboratory of Translational GastroenterologyQilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina

in this editorial,we comment on the article by Wang et al published in the recent issue of the World Journal of Gastroenterology in *** focused on identifying risk factors for lymph node metastasis(LNM)in superficial esophageal squamous cell carcinoma(sEsCC)patients and how to construct a simple and reliable clinical prediction model to assess the risk of LNM in sEsCC patients,thereby helping to guide the selection of an appropriate treatment *** current standard treatment for sEsCC is radical esophagectomy with lymph node ***,esophagectomy is associated with considerable morbidity and *** resection(ER)offers a safer and less.invasive alternative to surgical resection and can enable the patient's quality of life to be maintained while providing a satisfactory ***,since ER is a localized treatment that does not allow for lymph node dissection,the risk of LNM in sEsCC limits the effectiveness of *** LNM status can aid in determining whether patients with sEsCC can be cured by ER without the need for additional *** studies have shown that tumor size,macroscopic type of tumor,degree of differentiation,depth of tumor invasion,and lymphovascular invasion are factors associated with LNM in patients with *** addition,tumor budding is commonly associated with LNM,recurrence,and distant metastasis,but this topic has been less covered in previous *** comprehensively evaluating the above risk factors for LNM,useful evidence can be obtained for doctors to select appropriate treatments for sEsCC patients.

关键词： superficial esophageal squamous cell carcinoma Endoscopic resection Lymph node metastasis Risk factors Tumor budding Predictive model

Patterns, processes, and differentiation mechanisms of China's transition from old to new economic drivers

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Journal of Geographical s.iences 2024年第9期34卷 1697-1718页

作者： yan Mingtao ZHAO Jianji yan Mingyue Key Research ins.itute of Yellow River Civilization and sustainable Development Henan UniversityKaifeng 475001HenanChina Collaborative innovation Center on Yellow River Civilization Jointly Built by Henan Province and Ministry of Education Henan UniversityKaifeng 475001HenanChina College of Cultural and Tourism Henan UniversityKaifeng 475001HenanChina

Transition from old to new economic drivers(TONED) is of great significance for optimizing economic structures. Using a combination of methods.including entropy weight technique for order preference by similarity to ideal solution, geospatial analysis, and optimal parameter geodetector, this study inves.igates the patterns and mechanisms of China's TONED in the prefecture-level cities from 2011 to 2020. The findings reveal that(1) the TONED exhibited a spatial distribution characterized by higher levels.in the east and lower levels.in the west, along with a pyramidal hierarchy of levels. The distribution of hot and cold spots roughly followed the Heihe-Yulin line.(2) The informatization levels, openness to the outside world, and urbanization played a dominant role in the TONED. The types of dual-factor interactions exhibited both dual-factor enhancement and non-linear enhancement effects.(3) The eastern and central regions were more likely to promote the TONED through enhanced informatization levels, whereas the western region relied more on increasing openness. This study finds that the TONED results from the combined effects of three geographical natures, each playing a dis.inct role. The recommendations provided can serve as a reference for China and other developing countries to implement the TONED in the context of deglobalization.

关键词： transition from old to new economic drivers pattern evolution differentiation mechanism geographical nature China

An Electrochemical Perspective of Aqueous Zinc Metal Anode

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Nano-Micro Letters 2024年第1期16卷 274-312页

作者： Huibo yan songmei Li Jinyan Zhong Bin Li school of Materials s.ience and Engineering Beihang UniversityBeijing 100191People’s Republic of China

Based on the attributes of nonflammability,environmental benignity,and cost-effectiveness of aqueous electrolytes,as well as the favorable compatibility of zinc metal with them,aqueous zinc ions batteries(AZiBs)become the leading energy storage candidate to meet the requirements of safety and low ***,aqueous electrolytes,acting as a double-edged sword,also play a negative role by directly or indirectly causing various parasitic reactions at the zinc anode *** reactions.include hydrogen evolution reaction,pas.ivation,and dendrites,resulting in poor Coulombic efficiency and short lifespan of AZiBs.A comprehensive review of aqueous electrolytes chemistry,zinc chemistry,mechanism and chemistry of parasitic reactions,and their relations.ip is ***,the understanding of strategies for suppres.ing parasitic reactions from an electrochemical perspective is not profound *** this review,firstly,the chemistry of electrolytes,zinc anodes,and parasitic reactions and their relations.ip in AZiBs are deeply ***,the strategies for suppres.ing parasitic reactions from the perspective of enhancing the inherent thermodynamic stability of electrolytes and anodes,and lowering the dynamics of parasitic reactions at Zn/electrolyte interfaces are ***,the perspectives on the future development direction of aqueous electrolytes,zinc anodes,and Zn/electrolyte interfaces are presented.

关键词： Aqueous zinc ions batteries Parasitic reactions Aqueous electrolyte Zinc anode

Climatic implications.in earlywood and latewood width indices of Chinese pine in north central China

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Journal of Forestry Research 2024年第3期35卷 143-153页

作者： Kaixuan yang Junzhou Zhang Haowen Fan Yuan yan College of Geographic s.iences Qinghai Normal UniversityXining 810016People's Republic of China Key Laboratory of Tibetan Plateau Land surface Processes and Ecological Conservation(Ministry of Education) Xining 810016People's Republic of China Key Laboratory of Western China's Environmental systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030People's Republic of China Gansu Liancheng Forest Ecosystem Field Observation and Research station Lanzhou UniversityLanzhou 730333People's Republic of China school of Geography and information Engineering University of GeoscienceWuhan 430074People's Republic of China

Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern ***,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often prevent registration of climate signals of the LWW *** this study,328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites.in the Hasi Mountains,north central *** climate responses of these chronologies were analyzed and the LWW index used to derive sum-mer precipitation *** analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW,rather than those of the current year with infrequent summer climate ***,after removing the effect of earlywood growth using a simple regres.ion model,the adjusted LWW chronology(LWW_(adj))showed a strong relations.ip with July precipitation in dry *** suggests that the LWW_(adj) chronology has the potential to be used to inves.igate long-term variability in summer precipitation in drought-limited regions.

关键词： Dendroclimatology Latewood width Climate response summer precipitation Earlywood effect

Micro-flow structure at regime transition from bubbling to turbulent fluidization in a fluidized bed

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Particuology 2024年第6期89卷 117-130页

作者： Chaoyu yan Yue Yuan Xiaoyang Wei Jesse Zhu state Key Laboratory of Heavy Oil Proces.ing Beijing Key Laboratory of Process Fluid Filtration and SeparationCollege of Mechanical and Transportation EngineeringChina University of PetroleumBeijing 102249China China Beacons.ins.itute The University of NottinghamNingbo315100China Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity *** fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the system performance in practical *** the convoluted hydrodynamics are quantitively evaluated through numerous data-proces.ing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent ***,this study was to exploit a coupling data proces.ing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet multiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent *** transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).The results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bottom *** wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency *** sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics.in the fluidized *** micro-scale signal has the characteris.ic information of bubbling fluidization,and the characteris.ic information of turbulent fluidization is mainly represented by the meso-scale *** work provides a systematic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis.in this sector.

关键词： Flow regime transition Bubbling fluidization Turbulent fluidization Micro-flow structure Differential pressure fluctuation

An Uncertainty Evaluation on the ΔK_(th) and ΔK_(iC) of Fine-grained isotropic Graphite

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Acta Mechanica solida sinica 2024年第3期37卷 478-486页

作者： yantian Zhang Lina Zhu Ruiguo yan Xishu Wang Department of Engineering Mechanics Tsinghua UniversityBeijing100084China Wheel-Rail Center Tianjin Research Institute for Advanced EquipmentTsinghua UniversityTianjin300300China

This paper intensively explores the critical issues related to the quantitative and accurate evaluations of FCG behavior in the early stage,macro fatigue fracture toughness,and the critical crack size for damage tolerance in nuclear *** address these issues,scale-span FCG tests were carried out using two typical specimens,CT and sEM in-situ *** results.indicate that the FCG threshold and the effective FCG length have a significant correlation with the modified maximum loop stress theory for a mixed i/ii *** particular,the effective FCG length(a_(eq))and the applied stress threshold of polycrystalline graphite are important parameters for fatigue damage tolerance design in engineering *** influencing factors of ΔK_(th,eq) and a_(eq) were discussed in detail using the mixed i/ii mode,*** addition,the scattered values of ΔK_(iC) for this graphite can be quantitatively es.imated using the Weibull distribution *** predicated parameters and experimental results demonstrate a strong correlation.

关键词： Nuclear graphite Mixed i/ii mode Fatigue crack Fatigue crack growth threshold Fatigue fracture toughness

The structure Entropy of social Networks

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Journal of systems s.ience & Complexity 2024年第3期37卷 1147-1162页

作者： Li Zhenpeng yan Zhihua yanG Jian TANG Xijin school of Electronics and information Engineering Taizhou UniversityLinhai 317000China Academy of Mathematics and systems s.ience Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of smart City in Cyberspace security Yuxi Normal UniversityYuci 653100China University of Chinese Academy of s.iences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex *** this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in *** proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given *** analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency *** paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure ***,the authors find that the high proportion of reciprocity and transitivity results.in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

Recovery of scandium from silicate minerals by high-pressure leaching in sulfuric acid

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Journal of Rare Earths 2024年第7期42卷 1375-1384,I0007页

作者： Peng yan Xiaoming Chen Likun Gao Bo yang Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming650093China school of Chemistry and Chemical Engineering Kunming UniversityKunming650214China

This study inves.igated the leaching of scandium from a sc-bearing silicate *** sc concentrate obtained by beneficiation pre-enrichment has 1.03×10^(−4) wt%sc and 14.66 wt%*** main sc-bearing minerals are limonite,chlorite,sericite,and hornblende,in the form of ***-pressure leaching(HPL)with sulfuric acid(98 wt%)and NaF was used to dispose this *** sc leaching efficiency of 91.82%was obtained under the optimum conditions,which are pressure of 5.0×10^(5) Pa,A/O value of 1.1,L/s value of 1.8,NaF dosage of 2 wt%,at 130℃ for 6 *** X-ray diffraction(XRD)and scanning electron microscopy(sEM)results show that the residue is mainly quartz phase in the multihole *** with ordinary leaching for silicate,high-pressure leaching has significant advantages.in saving acid and energy consumption.

关键词： silicate minerals scandium High-pressure Leaching Concentrated sulfuric acid Rare earths

Porous silica nano-flowers stabilized Pt-Pd bimetallic nanoparticles as heterogeneous catalyst for efficiently synthesizing guaiacol from 2-methoxycyclohexanol

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Chinese Journal of Chemical Engineering 2024年第6期70卷 222-233页

作者： Junbo Feng Junyan Wu Dongdong yan Yadong Zhang school of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China state Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization Pingdingshan 467000China Jiyuan Research ins.itute Zhengzhou UniversityJiyuan 459000China school of Materials and Chemical Engineering Zhongyuan University of TechnologyZhengzhou 450007China

Porous silica nano-flowers(KCC-1)immobilized Pt-Pd alloy NPs(Pt-Pd/KCC-1)with different mass ratios of Pd and Pt were successfully prepared by a facile in situ one-step reduction,using hydrazinium hydroxide as a reducing *** as-synthesized silica nanospheres possess radial fibers with a distance of 15 nm,exhibiting a high specific surface area(443.56 m^(2)·g^(-1)).Meanwhile,the obtained Pt-Pd alloy NPs are uniformly dispersed on the silica surface with a metallic particle size of 4-6 nm,which exist as metallic Pd and Pt on the surface of monodisperse KCC-1,showing the transfer of electrons from Pd to *** as-synthesized 2.5%Pt-2.5%Pd/KCC-1 exhibited excellent catalytic activity and stability for the continuous dehydrogenation of 2-methoxycyclohexanol to prepare *** with Pt or Pd single metal supported catalysts,the obtained 2.5%Pt-2.5%Pd/KCC-1 shows 97.2%conversion rate of 2-methoxycyclohexanol and 76.8%selectivity for guaiacol,which attributed to the significant synergis.ic effect of bimetallic Pt-Pd alloy ***,turn over frequency value of the obtained 2.5%Pt-2.5%Pd/KCC-1 NPs achieved 4.36 s^(-1),showing higher catalytic efficiency than other two monometallic *** pathways of dehydro-aromatization of 2-methoxycyclohexanol over the obtained catalyst are ***,the obtained 2.5%Pt-2.5%Pd/KCC-1 NPs prove their potential in the dehydrogenation of 2-methoxycyclohexanol,while the kinetics and mechanis.ic study of the dehydrogenation reaction over the catalyst in a continuous fixed-bed reactor may provide valuable information for the development of green,outstanding and powerful synthetic pathway of guaiacol.

关键词： supported catalyst Nanoparticles Dehydrogenation 2-Methoxycyclohexanol Guaiacol