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Increasing operational stability of journal bearing in hydraulic suspension micro-pump by herringbone grooved structure

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Science China(Technological Sciences) 2024年第3期67卷 853-862页

作者： hong tao XING GuanYing ZUO HuaiYu XUE Song LUO XiaoBing State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.

关键词： journal bearing herringbone groove hydrodynamic effect micro-pump

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Experimental and first-principles calculation of TiN growth mechanism on CeAlO_(3) surface in steel

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Journal of Iron and Steel Research(International) 2024年第2期31卷 452-463页

作者： Fei-hu He Jun Peng Fang Zhang Yong-bin Wang hong-tao Chang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina

Regular TiN is harmful to the toughness of steel,and its shape and size need to be *** the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the *** results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic *** calculation results indicate that there is no metallic bonding present in the CeAlO_(3) *** the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.

关键词： CeAlO_(3)-TiN inclusion Orientation relationship Crystal structure First principle Surface energy

A path planning algorithm for a crop monitoring fixed-wing unmanned aerial system

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Science China(Information Sciences) 2024年第8期67卷 5-23页

作者： Longhao QIAN Yi Lok LO Hugh hong-tao LIU Institute of Aerospace Studies University of Toronto Department of Mechanical Engineering The University of Hong Kong

With the growing demand for automation in agriculture, industries increasingly rely on drones to perform crop monitoring and surveillance. In this regard, fixed-wing unmanned aerial systems(UASs)are viable platforms for scanning a large crop field, given their payload capacity and range. To achieve maximum coverage without landing for battery replacement, an algorithm for producing a minimal required energy survey path is essential. Hence, an energy-aware coverage path planning algorithm is proposed *** constraints for a fixed-wing UAS to fly at low altitudes while achieving full coverage of the crop field are first analyzed. Then, the full path is decomposed into straight-line and U-turn primitives. Finally, an algorithm to calculate a combination of straight-line segments and U-turns is proposed to obtain the path with minimum required energy consumption. The genetic algorithm is used to efficiently determine the order of the straight-line paths to traverse. Case studies show that the proposed algorithm can produce planning results for a convex-polygon-shaped crop field.

关键词： aerial survey energy minimization fixed-wing UAS genetic algorithm path planning

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Nomograms and prognosis for superficial esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2024年第10期30卷 1291-1294页

作者： hong tao Lin Ahmed Abdelbaki Somashekar G Krishna Department of Internal Medicine Division of GastroenterologyHepatology and NutritionThe Ohio State University Wexner Medical CenterColumbusOH 43210United States

In recent years,endoscopic resection,particularly endoscopic submucosal dis-section,has become increasingly popular in treating non-metastatic superficial esophageal squamous cell carcinoma(ESCC).In this evolving paradigm,it is crucial to identify factors that predict higher rates of lymphatic invasion and poorer *** tumor size,deeper invasion,poorer differentiation,more infiltrative growth patterns(INF-c),higher-grade tumor budding,positive lymphovascular invasion,and certain biomarkers have been associated with lymph node metastasis and increased morbidity through retrospective reviews,leading to the construction of comprehensive nomograms for outcome *** validated by future prospective studies,these nomograms would prove highly applicable in guiding the selection of treatment for superficial ESCC.

关键词： Esophageal cancer Esophageal squamous cell carcinoma Esophageal resection Endoscopic mucosal resection Endoscopic submucosal dissection Lymph node metastasis

Surface-induced Microstructure and Performance Changes in P3HT Ultrathin Films

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Chinese Journal of Polymer Science 2024年第6期42卷 805-814页

作者： hong-tao Shan Jia-Xin He Bing-Yan Zhu Xue-Ting Cao Ying-Ying Yan Jian-Jun Zhou hong Huo Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing100875China

In this work,poly(3-hexylthiophene)(P3HT)ultrathin films(P3HT-T)were prepared by spin-coating a dilute P3HT solution(in a toluene:o-dichlorobenzene(Tol:ODCB)blend with a volume ratio of 80:20)with ultrasonication and the addition of the nucleating agent bicycle[2.2.1]heptane-2,3-dicarboxylic acid disodium salt(HPN-68L)on glass,Si wafers and indium tin oxide(ITO)*** electrical and mechanical properties of the P3HT-T ultrathin films were investigated,and it was found that the conductivity and crack onset strain(COS)were simultaneously improved in comparison with those of the corresponding pristine P3HT film(P3HT-0,without ultrasonication and nucleating agent)on the same substrate,regardless of what substrate was ***,the conductivity of P3HT-T ultrathin films on different substrates was similar(varying from 3.7 S·cm^(-1)to 4.4 S·cm^(-1)),yet the COS increased from 97%to 138%by varying the substrate from a Si wafer to *** grazing-incidence wide-angle X-ray diffraction(GIXRD),UV-visible(UV-Vis)spectroscopy and atomic force microscopy(AFM),we found that the solid order and crystallinity of the P3HT-T ultrathin film on the Si wafer are highest,followed by those on glass,and much lower on ***,the surface energy and roughness of three substrates were investigated,and it was found that the polar component of the surface energyγp plays a critical role in determining the crystalline microstructures of P3HT ultrathin films on different *** work indicates that the P3HT ultrathin film can obviously improve the stretchability and simultaneously retain similar electrical performance when a suitable substrate is *** findings offer a new direction for research on stretchable CP ultrathin films to facilitate future practical applications.

关键词： P3HT ultrathin film Substrate Crystalline microstructures Polar component of the surface energy Electrical and stretchable performances

The Mass Assembly History for Galaxies with MaNGA

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Research in Astronomy and Astrophysics 2024年第3期24卷 58-69页

作者： Xue Ge hong-tao Wang Cheng-Long Lei Yun-Jun Guo Yi-Long Jiang Xiao-Xiao Cao School of Physics and Information Engineering Jiangsu Second Normal University Jiangsu Province Engineering Research Center of Basic Education Big Data Application Jiangsu Second Normal University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education School of Science Langfang Normal University

How galaxies assemble masses through their own star formation or interaction with the external environment is still an important topic in the field of galaxy formation and *** use Value Added Catalogs with galaxy features that are spatially and temporally resolved from Sloan Digital Sky Survey Data Release 17 to investigate the mass growth histories of early-type galaxies(ETGs)and late-type galaxies(LTGs).We find that the mass growth of ETGs is earlier than that of LTGs for massive galaxies(M_(*)>10^(10)M_⊙),while low-mass(M_(*)≤10^(10)M_⊙)ETGs have statistically similar mass assembly histories as low-mass *** stellar metallicity of all massive galaxies shows a negative gradient and basically does not change with ***,in low-mass galaxies,the stellar metallicity gradient of elliptical galaxies is negative,and the stellar metallicity gradient of lenticular and spiral galaxies evolves from positive to *** are not all in a high-density environment,but exhibit mass *** the tidal strength increases,the star formation rate of low-mass ETGs rapidly *** results support a picture where massive galaxies exhibit inside-out quenching mode,while low-mass galaxies show outside-in quenching *** effects play an important role in regulating the mass assembly histories of low-mass ETGs.

关键词： Galaxy evolution-galaxies star formation-Galaxy formation

Yuan Huiqin: Master of Peking Opera

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China News Release 2024年第3期 23-25页

作者： tao hong 不详

Peking Opera,a traditional Chinese art form originating in Beijing with a history spanning some 200 years,holds a unique position due to its early association with the imperial *** its significance,the United Nations Educational,Scientific and Cultural Organization approved the inclusion of Peking Opera on its Representative List of the Intangible Cultural Heritage of Humanity on November 16,2010.

关键词： Opera holds Peking

Primary pulmonary meningioma and minute pulmonary meningothelial-like nodules: Rare pulmonary nodular lesions requiring more awareness in clinical practice

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World Journal of Clinical Cases 2024年第11期12卷 1857-1862页

作者： Li-Dan Liu Ke-Xin Zhang Hai-Ning Zhang Yi-Wen Zheng hong-tao Xu Department of Pathology The First Hospital and College of Basic Medical Sciences of China Medical UniversityShenyang 110001Liaoning ProvinceChina

In this editorial,we comment on an article by Ruan et al published in a recent issue of the World Journal of Clinical *** meningothelial proliferative lesions,including primary pulmonary meningiomas,minute pulmonary meningothelial-like nodules,and metastatic pulmonary meningiomas are rare pulmonary *** lesions are difficult to differentiate from lung cancers based on clinical and imaging ***,we briefly introduce the clinical,imaging,and pathological characteristics of these lesions and discuss their pathogenesis to strengthen the current understanding of pulmonary meningothelial proliferative lesions in clinical diagnosis and therapy.

关键词： Pulmonary meningothelial proliferation Primary pulmonary meningioma Minute pulmonary meningothelial-like nodule Lung neoplasm Rare pulmonary nodular lesion

Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques

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Nuclear Science and Techniques 2024年第6期35卷 78-89页

作者： Xian-Lin Yang Chang-Lin Lan Yu-Ting Wei Yi Zhang Gong Jiang Bo Xie Yu Liu hong-tao Shen Xiao-Jun Sun School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China

Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great *** address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion *** the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He ***^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of *** neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb *** measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature *** newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental *** obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.

关键词： 14-MeV neutron ^(27)Al(n,2n)^(26)Al Cross section AMS