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Best m-term One-sided Trigonometric Approximation of Some Function Classes Defined by a Kind of Multipliers

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Acta Mathematica Sinica,English Series 2010年第5期26卷 975-984页

作者： Ren suo li Yong Ping liU School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China Department of Mathematics Shandong Agricultural University Tai ' an 271018 P. R. China

In this paper, we continue studying the so-called non-linear best m-term one-sided approximation problems and obtain the asymptotic estimations of non-linear best m-term one-sided trigonometric approximation under the norm Lp （1 ≤ p ≤ ∞） of multiplier function classes and the corresponding m-term Greedy-liked one-sided trigonometric approximation results.

关键词： non-linear best m-term approximation one-sided approximation Lp spaces trigonometric function system and Greedy approximation algorithm

Successful treatment of floating splenic volvulus:Two case reports and a literature review

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World Journal of Clinical Cases 2021年第29期9卷 8812-8819页

作者： Chi Sun suo-lin li Department of Pediatric Surgery The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND The floating spleen refers to the spleen moving away from the normal anatomical position to other parts of the abdominal *** SUMMARY In this report,we describe two cases of torsion of floating spleen,which were successfully treated by laparoscopic partial splenectomy and retroperitoneal fixation of the residual *** clinical characteristics of previously reported cases are also *** In conclusion,laparoscopic partial resection of splenic volvulus infarction and extraperitoneal fixation of residual spleen are safe and reliable.

关键词： Laparoscopic infarction splenectomy Retroperitoneal fixation of residual spleen Splenic volvulus Wandering spleen Case report

Temperature Effect on the Mechanical Behavior of Acrylic Polymers under Quasi-static and Dynamic Loading

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上海交通大学学报 2004年第z2期38卷 89-95页

作者： Tao suo Yulong li Hong Yu Fei Xu Zhongbin Tang Lei li School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China Beijing Institute of Aeronautical Materials Beijing100095China

In this paper, the mechanical behavior of acrylic polymers at elevated temperature was investigated. Four acrylic polymers were tested at high strain rate by using compression Hopkinson bar and at quasi-static strain rate by using an Instron servo hydraulic axial testing machine with the testing temperature from 218K to 393K. The results show that the mechanical property of acrylic polymers depends heavily on the testing temperature. The yield stress and Young's modulus were found to decrease with increasing temperature at low strain rate. At very low temperature, the materials display typical brittle fracture; however their plasticity improves remarkably at high temperatures. The predictions of the mechanical behavior including the effect of temperature and strain rate using a proposed theoretical model have a good agreement with experimental results.

关键词： acrylic polymer compression Hopkinson bar quasi-static dynamic fracture

Microstructure and grain boundary morphology evolution of a novel Co-9Al-9W-2Ta-0.02B alloy doped with yttrium

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Rare Metals 2017年第12期36卷 951-961页

作者： Jian-Qiang Ma Fei Zhong Shu-suo li Jiang-Bo Sha School of Materials Science and Engineering Beihang University Beijing 100191 China

The microstructures and grain boundary morphologies of a novel Co-9 Al-9 W-2 Ta-0.02 B alloy doped with yttrium(Y)(0.01,0.05,0.10,and 0.20; at%) were investigated as functions of aging temperatures(900 and1000 ℃) and time(50 and 150 h). The aged alloys all exhibit a γ/γ’-Co(Al,W) coherent microstructure in grain interiors, whereas an intermetallic κ-Co(W) phase precipitates at grain boundaries. Y is found to fully segregate at grain boundaries and changes grain boundary precipitate morphologies. For 0.01 Y alloy, bright κ-Co(W) stripes precipitate along grain boundaries, where a needlelike κ-Co(W) phase grows from grain boundaries or κ-Co(W) stripes toward grain interior. As the nominal Y content increases, the stripe and needlelike κ-Co(W) precipitates at grain boundaries are strongly restrained and disappear in 0.20 Y alloy, leaving fine κ-Co(W) particles scattered at grain boundaries. It is noted that more Y segregation may increase the number of low-angle grain boundaries(LABS, with misorientations of liminates O impurities from grain boundaries. Finally,the effect of Y segregation on tensile behavior of Co-AlW-Ta-B alloy was discussed from the viewpoints of grain boundary precipitate morphologies, grain boundary character distribution(GBCD), and impurity segregation.

关键词： Intermetallics Alloy design Grain boundary segregation Casting Microstructure

Structural evolution of plasma sprayed amorphous li_(4)Ti_(5)O_(12) electrode and ceramic/polymer composite electrolyte during electrochemical cycle of quasi-solid-state lithium battery

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Journal of Advanced Ceramics 2021年第2期10卷 347-354页

作者： Xi Wu Xinghua liang Xiaofeng Zhang lingxiao Lan suo li Qixin Gai Guangxi Key Laboratory of Automobile Components and Vehicle Technology Guangxi University of Science&TechnologyLiuzhou545006China National Engineering Laboratory for Modern Materials Surface Engineering Technology Guangdong Institute of New MaterialsGuangdong Academy of SciencesGuangzhou510650China

A quasi-solid-state lithium battery is assembled by plasma sprayed amorphous li_(4)Ti_(5)O_(12) to provide the outstanding electrochemical stability and better normal interface *** Electron Microscope(SEM),Scanning Transmission Electron Microscopy(STEM),Transmission Electron Microscopy(TEM),and Energy Dispersive Spectrometer(EDS)were used to analyze the structural evolution and performance of plasma sprayed amorphous LTO electrode and ceramic/polymer composite electrolyte before and after electrochemical *** comparing the electrochemical performance of the amorphous LTO electrode and the traditional LTO electrode,the electrochemical behavior of different electrodes is *** results show that plasma spraying can prepare an amorphous LTO electrode coating of about 8μ*** 200 electrochemical cycles,the structure of the electrode evolved,and the inside of the electrode fractured and cracks expanded,because of recrystallization at the interface between the rich fluorine compounds and the amorphous LTO ***,the ceramic/polymer composite electrolyte has undergone structural evolution after 200 test *** electrochemical cycle results show that the cycle stability,capacity retention rate,coulomb efficiency,and internal impedance of amorphous LTO electrode are better than traditional LTO *** innovative and facile quasi-solid-state strategy is aimed to promote the intrinsic safety and stability of working lithium battery,shedding light on the development of next-generation high-performance solid-state lithium batteries.

关键词： plasma spraying li_(4)Ti_(5)O_(12)(LTO)electrode ceramic/polymer composite electrolyte electrochemical cycle quasi-solid-state lithium battery

SAR-GMTI investigation in hybrid along-and cross-track baseline InSAR

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Science in China(Series F) 2009年第8期52卷 1399-1408页

作者： suo ZhiYong li ZhenFang BAO Zheng WU JianXin National Key Lab of Radar Signal Processing Xidian University Xi'an 710071 China

A joint-pixel clutter suppression method based on slope compensation is proposed in this paper, In order to eliminate the effect of the terrain interferometric phase caused by the cross-track baseline in hybrid baseline InSAR, the local independent identical distribution of the clutter is satisfied by using the slope compensation technique, and thus the clutter can be suppressed successfully by using the orthogonality of the clutter subspace and the noise subspace. This approach utilizes the information contained in the current pixel as well as in its neighbors, showing robustness to the image coregistration errors. Both the simulated data and the real airborne data are used in proving the validity of the presented approach.

关键词： interferometric synthetic aperture radar (InSAR) along-/cross-track baseline ground moving target indication (GMTI) slope compensation clutter suppression

Role of color Doppler flow imaging in applicable anatomy of spleen vessels

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World Journal of Gastroenterology 2009年第5期15卷 607-611页

作者： Wei-li Xu suo-lin li Yan Wang Meng li Ai-Guo Niu Department of Pediatric Surgery the Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China Department of Ultrasound the Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China

AIM： To explore the role of color Doppler flow imaging （CDFI） in visualization of spleen vessels and to define its value for spleen micro-invasive operation. METHODS： A total of 36 patients requiring laparoscopic splenectomy （LS） for various hematopathies and autoimmune diseases were randomly selected from April 2005 to May 2008. Anatomic types of spleen pedicle, adjacent relations between spleen vessels and pancreas, diameters of spleen artery and vein were detected and recorded by preoperative CDFI. Different operative procedures were performed according to different anatomic frameworks. The parameters were recorded by telerecording during LS and compared with those by preoperative CDFI using Chi-square test. RESULTS： Two anatomic types of spleen pedicle and four different adjacent relations between spleen vessels and pancreas were detected by CDFI. The diameters of spleen artery and vein detected by CDFI were 0.46 ± 0.09 cm and 0.85 ± 0.35 cm, respectively. There was no statistical difference between the parameters recorded by CDFI and by telerecording （X^2 = 0.250, 0.677, P 〉 0.05）. LS was successfully performed following the anatomic information provided by preoperative ***： Different anatomic frameworks of spleen vessels can be provided by preoperative CDFI, which instructs micro-invasive operation of spleen and increase the safety of operation.

关键词： Ultrasound, Color Doppler imaging Spleen Anatomy Laparoscopic operation

Electropolishing technique of Hastelloy C-276 alloy

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Rare Metals 2017年第8期36卷 635-639页

作者： Qiang Jia Yi Wang Hong-li suo Pan Wang Meng-Yuan li Qian-Yu Huo School of Materials Science and Engineering Beijing Universityof TechnologyBeijing 100022China

Preparing a highly textured,flawless YBa_（2-）Cu_3O_7（YBCO）layer by ion-beam-as sis ted deposition（IBAD）requires a substrate with a smooth *** this paper,smooth tapes of Hastelloy C-276,a common template alloy,were prepared by electrochemical polishing,and the surface roughness the tapes was investigating by atomic force microscopy and scanning electron *** analyzing these results,it was discussed how the processing parameters affect the surface roughness,and it is found the following optimized processing parameters：current density of 0.104 A·cm^（-2）,temperature of 50℃,plate spacing of 9 cm and time of 150 *** these optimized parameters,the substrate roughness decreases to less than 5 nm,meeting the requirements of IBAD.

关键词： Hastelloy C-276 Electro-chemical polishing Atomic force microscopy Current density

Cyclic oxidation behavior of Ni_(3)Al-based single crystal alloy IC21

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Rare Metals 2023年第5期42卷 1656-1662页

作者： Tian-Tian Yang Xin Zhou Shu-suo li Yan-ling Pei Sheng-Kai Gong School of Materials Science and Engineering Beihang UniversityBeijing100191China

In this study,the cyclic oxidation tests of the Ni3Al-based single-crystal super alloy IC21 were carried out at 800,900,950,1000,1050 and 1100℃in *** present study shows that the complex oxide scale on the surface of the alloy is made up of an outer columnar NiO layer,an intermediate mixture of NiO and NiAl2O4layer with a small amount of Mo oxides and an inner continuous layer ofα-Al_(2)O_(3).The cyclic oxidation kinetics curves show that oxidation resistance at 800,900,950,1000 and1050℃seems to follow a similar law and is better than that at 1100℃.The overall weight changes at 1100℃follows a parabolic *** and severe rumpling of the oxide scale are observed on the surface of the alloy at1100℃,revealing the occurrence of disastrous oxidation.

关键词： Ni_(3)Al Thermal cycling Oxidation Microstructure