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胰腺黏液性囊性肿瘤的超声表现

中国医学影像技术 2012年第2期28卷 315-317页

作者：王鹏唐少珊刘守君中国医科大学附属盛京医院超声科辽宁沈阳110004

目的探讨胰腺黏液性囊性肿瘤(MCNs)的超声表现。方法回顾性分析42例经手术病理证实的MCNs的超声表现。结果 MCNs多发生于中年女性,大部分位于胰体尾部,肿瘤体积较大,边界清晰,多数有包膜。42例MCNs中,22例为囊性或以囊性为主;18例囊实... 详细信息

目的探讨胰腺黏液性囊性肿瘤(MCNs)的超声表现。方法回顾性分析42例经手术病理证实的MCNs的超声表现。结果 MCNs多发生于中年女性,大部分位于胰体尾部,肿瘤体积较大,边界清晰,多数有包膜。42例MCNs中,22例为囊性或以囊性为主;18例囊实混合性;2例实性。病理诊断良性病变24例,交界性7例,恶性11例。超声诊断:20例考虑为良性,22例考虑恶性,超声诊断恶性MCNs的敏感度为77.78%(14/18),特异度为66.67%(16/24)。结论 MCNs超声图像表现复杂,肿物内分隔厚度、是否存在实性部分有助于鉴别良、恶性病变。

关键词：胰腺肿瘤肿瘤,囊性,黏液性和浆液性超声检查

The Astrometric Performance of the China Space Station Telescope(CSST)Sky Survey in Extending the Gaia Celestial Reference Frame

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Research in Astronomy and Astrophysics 2024年第8期24卷 133-140页

作者： jun Yao Jia-Cheng liu Niu liu Zi Zhu Zhen-Wei Wang School of Astronomy and Space Science Key Laboratory of Modern Astronomy and Astrophysics(Ministry of Education)Nanjing UniversityNanjing 210023China University of Chinese Academy of Sciences Nanjing 211135China

The multi-color imaging sky survey conducted by the China Space Station Telescope(CSST)holds significant promise for advancing the development of the celestial reference *** this study,we focus on assessing the astrometric performance of the CSST celestial reference frame(CSST-CRF)in extending the Gaia Celestial Reference Frame 3(Gaia-CRF3).First,the orientation precision of the CSST reference frame is evaluated using a simulated set of extragalactic sources with CSST g magnitudes ranging from 18 to 25 *** estimated orientation uncertainty caused by random error insignificantly affects the alignment between Gaia-CRF3 and the ***,the systematic effect of incomplete CSST sky coverage on the alignment between CSST-CRF and Gaia-CRF3 is discussed by analyzing the differences between the subset of Gaia-CRF3 in the CSST observation region(Gaia-CRF3′)and Gaia-CRF3 as a *** the third International Celestial Reference Frame(ICRF3)S/X band as an intermediate reference frame,the orientation offset between Gaia-CRF3′and GaiaCRF3 is estimated to be 20μ*** offset is marginally larger than the orientation offset between Gaia-CRF3 and the ICRF3,approximately 15μ*** residual spin and glide rate of Gaia-CRF3′are derived from the proper motions,consistent with that of Gaia-CRF3 within the formal ***,we explore the role of CSST in establishing a multi-band celestial reference frame by comparing its limiting magnitude and observation accuracy with existing catalogs in the infrared and ultraviolet *** to its broad wavelength coverage and highprecision measurements,CSST is well-positioned to make significant contributions to the development of a multiband celestial reference frame.

关键词： astrometry-reference systems-surveys

Unstructured Road Extraction in UAV Images based on Lightweight Model

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 372-384页

作者： Di Zhang Qichao An Xiaoxue Feng Ronghua liu jun Han Feng Pan School of Automation Beijing Institute of TechnologyBeijing 100081China Tianjin Institute of Maritime Navigation Instruments Tianjin 300130China The 716th Research Institute of China Shipbuilding Group Co. LtdJiangsu 222061China

There is no unified planning standard for unstructured roads,and the morphological structures of these roads are complex and *** is important to maintain a balance between accuracy and speed for unstructured road extraction *** road extraction algorithms based on deep learning have problems such as high model complexity,high computational cost,and the inability to adapt to current edge computing ***,it is best to use lightweight network *** the need for lightweight models and the characteristics of unstructured roads with different pattern shapes,such as blocks and strips,a TMB(Triple Multi-Block)feature extraction module is proposed,and the overall structure of the TMBNet network is *** TMB module was compared with SS-nbt,Non-bottleneck-1D,and other modules via *** feasibility and effectiveness of the TMB module design were proven through experiments and *** comparison experiment,using multiple convolution kernel categories,proved that the TMB module can improve the segmentation accuracy of the *** comparison with different semantic segmentation networks demonstrates that the TMBNet network has advantages in terms of unstructured road extraction.

关键词： Unstructured road Lightweight model Triple Multi-Block(TMB) Semantic segmentation net

Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： En-wen ZHU Zi-wei DENG Han-jun ZHANG jun CAO Xiao-hui liu Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV *** first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant *** semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

In Vivo Voltammetric Imaging of Metal Nanoparticle-Catalyzed Single-Cell Electron Transfer by Fermi Level-Responsive Graphene

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Research 2024年第1期2023卷 271-280页

作者： Qing Xia Rui liu Xueqin Chen Zixuan Chen jun-Jie Zhu State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023P.R.China Shenzhen Research Institute of Nanjing University Shenzhen 518000P.R.China

Metal nanomaterials can facilitate microbial extracellular electron transfer(EET)in the electrochemically active ***,the role of nanomaterials/bacteria interaction in this process is still ***,we reported the single-cell voltammetric imaging of Shewanella oneidensis MR-1 at the single-cell level to elucidate the metal-enhanced EET mechanism in vivo by the Fermi level-responsive graphene *** oxidation currents of~20 fA were observed from single native cells and gold nanoparticle(AuNP)-coated cells in linear sweep voltammetry *** the contrary,the oxidation potential was reduced by up to 100 mV after AuNP *** revealed the mechanism of AuNP-catalyzed direct EET decreasing the oxidation barrier between the outer membrane cytochromes and the *** method offered a promising strategy to understand the nanomaterials/bacteria interaction and guide the rational construction of EET-related microbial fuel cells.

关键词： Fermi voltammetry Electron

Highly coupled off-resonance lattice design in diffraction-limited light sources

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Nuclear Science and Techniques 2024年第9期35卷 92-102页

作者： Yi-Hao Gong Shun-Qiang Tian Xin-Zhong liu shou-Zhi Xuan Li-Yuan Tan Ling-Long Mao Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204 ShanghaiChina Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 ShanghaiChina University of Chinese Academy of Sciences 100049 BeijingChina

The round-beam operation presents many benefits for scientific experiments regarding synchrotron radiation and the weak-ening influences of intra-beam scattering in diffraction-limited synchrotron light sources.A round-beam generation method based on the global setting of skew quadrupoles and the application of a non-dominated sorting genetic algorithm was pro-posed in this *** schemes,including large-emittance coupling introduced via betatron coupling and vertical disper-sion,were explored in a candidate lattice for an upgrade-proposal of the Shanghai synchrotron radiation *** variations with lattice imperfections and their influence on the beam dynamics of beam optic distortions were *** results demonstrated that a precise coupling control ranging from 10 to 100%was achieved under low optical distortion,whereas full-coupling generation and its robustness were achieved by our proposed method by adjusting the skew quadrupole components located in the dispersion-free *** Touschek lifetime increased by a factor of 2–2.5.

关键词： Diffraction-limited storage ring(DLSR) Shanghai synchrotron radiation facility upgrade(SSRF-U) Round beam Off-resonance coupling

Dealloyed TiCuMn efficiently catalyze the NO reduction and Zn-NO batteries

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 51-59页

作者： Lang Zhang Tong Hou Weijia liu Yeyu Wu Tianran Wei junyang Ding Qian liu jun Luo Xijun liu State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals and MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Education Department of Guangxi Zhuang Autonomous Region Key Laboratory of Applied Analytical ChemistryGuangxi Collaborative Innovation Center for Chemistry and Engineering of Forest ProductsGuangxi Key Laboratory of Chemistry and Engineering of Forest ProductsKey Laboratory of Chemistry and Engineering of Forest ProductsState Ethnic Affairs CommissionSchool of Chemistry and Chemical EngineeringGuangxi Minzu UniversityNanning 530006China Institute for New Energy Materials&Low-Carbon Technologies School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Institute for Advanced Study Chengdu UniversityChengdu 610106China ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of ChinaShenzhen 518110China

Electrocatalytic NO reduction reaction offers a sustainable route to achieving environmental protection and NH3 production targets as *** this work,a class of dealloyed Ti_(60)Cu_(33)Mn_(7)ribbons with enough nanoparticles for the high-efficient NO reduction reaction to NH_(3)is fabricated,reaching an excellent Faradaic efficiency of 93.2%at–0.5 V vs reversible hydrogen electrode and a high NH3 synthesis rate of 717.4μmol·h^(-1)·mgcat.-1 at–0.6 V vs reversible hydrogen *** formed nanoparticles on the surface of the catalyst could facilitate the exposure of active sites and the transportation of various reactive ions and ***,the Mn content in the TiCuMn ribbons modulates the chemical and physical properties of its surface,such as modifying the electronic structure of the Cu species,optimizing the adsorption energy of N^(*)atoms,decreasing the strength of the NO adsorption,and eliminating the thermodynamic energy barrier,thus improving the NO reduction reaction catalytic ***,a Zn-NO battery was fabricated using the catalyst and Zn plates,generating an NH3 yield of 129.1µmol·h^(-1)·cm^(-2)while offering a peak power density of 1.45 mW·cm^(-2).

关键词： nitric oxide reduction NH3 electrosynthesis TiCuMn alloy Mn modulation Zn-NO battery

Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin liu Ming-Fu Lyu Heng-Yuan Zhang Jian-Ye liu Shi-jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology

Lotus root-like RuIr alloys with close-packed(0001)branches:Strain-driven performance for acidic water oxidation

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Journal of Energy Chemistry 2024年第5期92卷 579-590页

作者： Mingyue Xiao Wanli Xu Rongchao Li Yanhui Sun Jingjun liu Feng liu jun Gan Shixin Gao Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing University of Chemical TechnologyBeijing 100029China Yunnan Precious Metals Lab Kunming 650100YunnanChina

Achieving composition tunability and structure editability of nanoalloys with high level strain may be an efficient strategy to remarkably boost catalytic performance toward oxygen evolution reaction(OER)in acidic water ***,lotus root-like RuIr alloys with native micro-strain were constructed by an epitaxial growth of Ru-richened hcp-(0001)branches on Ir-richened fcc-(111)seeds using a polyol thermal synthesis *** resultant Ru_(60)Ir_(40) alloy shows an OER overpotential of 197 mV at 10 mA cm^(-2) and a Tafel slope of 46.59 mV dec^(-1),showing no obvious activity decay for 80 h continuous chronopotentiometry test in 0.5 M H_(2)SO_(4).The related characterizations including X-ray absorption fine structure(XAFS)spectroscopy and density functional theory(DFT)calculations show that that the remarkably improved activity of the lotus root-like alloy can be attributed to the(0001)facet-triggered strain,which can efficiently optimize the electronic band structure of the active metal and the weakening of the chemisorption of oxygen-containing substances to boost OER ***,this work provides a new strategy to designing a class of advanced electrocatalysts with high strain using diverse nanostructures as building materials for carbon-free clean energy conversion systems.

关键词： Rulr alloy Lotusroot-like structure Strain Oxygene volution reaction Activity