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A rotary ultrasonic motor using radial bending mode of ring with nested PZT excitation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 189-196页

作者： ying-xiang liu jun-kao liu Wei-shan CHEN Xiao-hui YANG State Key Laboratory of Robotics and System Harbin Institute of Technology Horbin 150001 China

This study presents and verifies a new idea for constructing a rotary traveling wave ultrasonic motor （USM） that uses the radial bending mode of a ring. In the new design, 20 trapezoid cross section slots are cut symmetrically in the outer surface of a thick duralumin alloy ring, where 20 PZT stacks are nested. In each slot, two wedging blocks are set between the PZT stack and the two sides of the slot respectively to apply preloading on the PZT ceramics. Two radial bending modes of the stator that have a phase difference of a quarter wavelength on space are generated by using the d33 operating mode of the PZT elements, and then a flexural traveling wave is formed by the superimposing of two standing waves whose amplitudes are equal and phases are different by 90~ temporally. Two conical rotors are pressed to each end of the ring type stator by a coiled spring. The finite element method （FEM） simulation is developed to validate the feasibility of the proposed motor. The maximal speed and torque of the prototype are tested to be 126 r/rain and 0.8 N＇m, respectively.

关键词： Rotary ultrasonic motor Radial bending mode Traveling wave Wedging block clamped structure

Unusual immunohistochemical“null”pattern of four mismatch repair proteins in gastric cancer:A case report

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World Journal of Clinical Cases 2021年第21期9卷 6102-6109页

作者： Meng Yue jun-ying liu Yue-Ping liu Department of Pathology The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina

BACKGROUND Immunohistochemical(IHC)staining for mismatch repair(MMR)proteins is useful for gastric cancer treatment and *** IHC staining patterns reflect the complex biological phenomena underlying MMR *** herein report a rare IHC staining pattern of four MMR-related proteins in gastric *** SUMMARY A“null”IHC staining pattern of four MMR-related proteins,including MLH1,PMS2,MSH2,and MSH6,in a 67-year-old male patient with gastric cancer pT3N3aM0 revealed promoter hypermethylation of ***-generation sequencing showed that these four genes exhibited *** of these was the somatic mutation of the missing copy number in exon 14 of *** analysis using peripheral blood showed no germline mutations in these four *** patient had no history of personal or family tumor *** classified this case as *** patient returned to normal after operation,and there were no signs of tumor metastasis and *** six cycles of adjuvant chemotherapy,the patient was discharged in a stable *** patient had a mild reaction to chemotherapy and a good *** present,16 mo after the operation,the patient's condition is *** Abnormal MMR protein expression,helpful for individualized follow-up care,helped identify a sporadic case lacking familial clinical management implications.

关键词： Gastric cancer Mismatch repair proteins Next-generation sequencing Sporadic Family management Case report

A Review on Graphene Oxide Two-dimensional Macromolecules: from Single Molecules to Macro-assembly

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Chinese Journal of Polymer Science 2021年第3期39卷 267-308,I0004页

作者： Wen-Zhang Fang Li Peng ying-jun liu Fang Wang Zhen Xu Chao Gao Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Made by chemical oxidation of graphite, GO is highly dispersible or even solubilized in water and polar organic solvents, which resolves the hard problem of graphene processing and opens a door to wet-processing of graphene. Despite its defects, GO is easy to functionalize, dope, punch holes, cut into pieces, conduct chemical reduction, form lyotropic liquid crystal, and assemble into macroscopic materials with tunable structures and properties as a living building block. GO sheet has been viewed as a single molecule, a particle, as well as a soft polymer material. An overview on GO as a 2 D macromolecule is essential for studying its intrinsic properties and guiding the development of relevant subjects. This review mainly focuses on recent advances of GO sheets, from single macromolecular behavior to macro-assembled graphene material properties. The first part of this review offers a brief introduction to the synthesis of GO molecules. Then the chemical structure and physical properties of GO are presented, as well as its polarity in solvent and rheology behavior. Several key parameters governing the ultimate stability of GO colloidal behavior, including size, p H and the presence of cation in aqueous dispersions, are highlighted. Furthermore, the discovery of GO liquid crystal and functionalization of GO molecules have built solid new foundations of preparing highly ordered, architecture-tunable, macro-assembled graphene materials, including 1 D graphene fibers, 2 D graphene films, and 3 D graphene architectures. The GO-based composites are also viewed and the interactions between these target materials and GO are carefully discussed. Finally, an outlook is provided in this field, where GO is regarded as macromolecules, pointing out the challenges and o

关键词： Graphene 2D macromolecules Macro-assembly

Doping Effect of CuO on CeO_2 for CO Oxidation

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Chinese Chemical Letters 1998年第9期9卷 873-876页

作者： Ji jun ZHANG Neng LI ying jun liu Bing Xiong LIN(Institute of Physical Chemistry, Peking University, Beijing 100871) Institute of Physical Chemistry Peking University Beijing 100871 China

Cu-Ce-O catalysts, prepared by the amorphous citrate precursor (ACP) method, wereinvestigated by ICP, XRD and ndcro-reactor techniques. At low copper content of Cu-Ce-Ocatalysts, fluorite structures formed at low calcining temperatures, and Cuo doped into the CeO2matrix; at high copper content, in addition to the fluorite structure, crystalline monoclinic phaseCuO formed as well at high calcining temperatures. There was no other phase formed even calcinedat 1000℃. The results show that only a little CuO dopes into the CeO2 matrix to form complexoxide, which promotes the catalytic activity of CO oxidation greatly. The optimum Cu-Ce-Ocatalyst is composed of 15% copper by Cu/(Ce+Cu) atomic ratio, and calcined at 700℃ for 4h. Thephase compositions include the crystalline CuO and the active complex oxide with fluoritestructure. The formulation of the active complex oxide is Cu0.06Ce0. 94O1.94.

关键词： ceria copper oxide fluorite-type structure, CO oxidation catalyst, doping effect

Circulating copeptin level and the clinical prognosis of patients with chronic liver disease

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World Journal of Gastroenterology 2023年第31期29卷 4797-4808页

作者： Hao-Qian Tan Ming Zhao Zan Huang Yang liu Han Li Long-Hui Ma jun-ying liu Department of Gastroenterology Zhoukou Central Hospital Affiliated to Xinxiang Medical UniversityZhoukou 466000Henan ProvinceChina Department of Gastroenterology Zhoukou Central HospitalZhoukou 466000Henan ProvinceChina Department of Teaching and Research Zhoukou Central HospitalZhoukou 466000Henan ProvinceChina

BACKGROUND The relationship between copeptin and the severity of circulatory dysfunction and systemic stress response in patients with chronic liver disease(CLD)has been ***,the potential of serum copeptin levels to predict the prognosis of CLD patients remains *** To conduct a systematic review and meta-analysis to investigate the correlation between serum copeptin and transplant-free survival(TFS)in this *** To achieve the objective of the meta-analysis,PubMed,Embase,the Cochrane Library,and the Web of Science were searched to identify observational studies with longitudinal *** Cochrane Q test was utilized to assess betweenstudy heterogeneity,and the I2 statistic was ***-effects models were employed to combine the outcomes,taking into account the potential influence of *** Ten datasets including 3133 patients were *** follow-up durations were 1 to 48 mo(mean:12.5 mo).Overall,it was shown that a high level of serum copeptin was associated with a poor TFS[risk ratio(RR):1.82,95%confidence interval:1.52-2.19,P0.05).CONCLUSION Patients with CLD who have high serum copeptin concentrations may be associated with a poor clinical prognosis.

关键词： Chronic liver disease Liver cirrhosis Copeptin Prognosis Mortality Meta-analysis

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu ying Cheng Xiao-jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Separation of chiral drugs with sulfobutylether-β-cyclodextrin bycapillary zone electrophoresis

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Chinese Chemical Letters 1999年第1期10卷 39-42页

作者： jun ying liu Yi Yang DONG Tian Song WANG Hu Wei liu Al Jin HUANG yi Liang SUNI Zeng Pei SUN(Department of Chemistry． Peking University． Beijing 100871)(Natlonal Institute for the Control of Pharmaceutical and Biological Products，Beijing 100050) Department of Chemistry Peking University Beijing 100871 China Natl. Inst. Contr. Pharmaceutical B. Beijing 100050 China

Sulfobutylether－β－cyclodextrin（SBE－β－CD）was used as a chiral selector tor separatingten chlral drugs with resolution 1．2 by capillary zone electrophoresls（CZE）， The backgroundelectrolylc solution comprised of 120 mmol／L Britton－Robinson buffer（BRB） containing1 ～10mmol／L SBE－β－CD with the pH value adjusted from 5．0－6．8． Five of the drugs were better resolvedthan those previously reported with neutral CDs．

关键词： Chiral separation sulfobutylether-β-cyclodextrin capillary zone electrophoresis anlsodamlne bencynonate econazole esmolol glycopynonate lobeline methoxamine phenylephrine plnacidll terazosin

Approach from the laboratory to the field: New strategies in the control of mosquito-borne infectious diseases

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Science China Life Sciences 2025年第1期68卷 303-305页

作者： Ziqian Xu Lianpan Dai jun liu National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases (NITFID) National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences

Vector-borne viruses, transmitted among humans and animal hosts through bites of vectors such as mosquitoes and ticks,pose a great and ongoing threat to public health and biosafety(Yang et al., 2022).Among them, dengue virus-induced epidemics, have dramatically increased worldwide in recent decades. The report released by the World Health Organization(WHO) at the end of 2023 showed that dengue epidemic globally surged in2023, with the number of reported cases nearing a historical peak.

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Structural engineering of high-entropy alloys for advanced electrocatalytic reactions

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Tungsten 2025年第1期7卷 1-31页

作者： Qiao Xie ying-Jie Yu Hai-jun Zhang Ya-Ping Deng Wen Lei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Department of Chemical Engineering Waterloo Institute for Sustainable Energy Waterloo Institute for Nanotechnology University of Waterloo

High-entropy alloys(HEAs) have emerged as promising candidates to replace traditional precious metal catalysts,owing to their unique chemical and physical *** review commences by revisiting the fundamental concepts of HEAs,including their synthesis methods and structural control strategies in *** underscores the critical role of meticulously manipulating both macroscopic and microscopic structures of the HEAs to optimize their catalytic performance.A deep understanding of the structure-activity relationship in HEAs across various configurations is pivotal in developing more effective *** review methodically encapsulates the research progress of structural control strategies for HEAs in achieving efficient energy conversion,with the aim of gaining a better understanding of the relationship between structure and *** review concludes by summarizing the current achievements and challenges,and suggestions for potential future directions of HEAs in the fields of energy conversion and environmental purification.

关键词： Electrocatalytic Energy conversion High-entropy alloys Structural modulation