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Transfer matrix method for free and forced vibrations of multi-level functionally graded material stepped beams with different boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 983-1000页

作者： Xiaoyang SU Tong hu Wei ZHANG Houjun KANG Yunyue CONG quan yuan School of Civil Engineering and Architecture Guangxi UniversityNanning 530004China Scientific Research Center of Engineering Mechanics Guangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Guangxi UniversityNanning 530004China

Functionally graded materials(FGMs)are a novel class of composite materials that have attracted significant attention in the field of engineering due to their unique mechanical *** study aims to explore the dynamic behaviors of an FGM stepped beam with different boundary conditions based on an efficient solving *** the assumptions of the Euler-Bernoulli beam theory,the governing differential equations of an individual FGM beam are derived with Hamilton’s principle and decoupled via the separation-of-variable ***,the free and forced vibrations of the FGM stepped beam are solved with the transfer matrix method(TMM).Two models,i.e.,a three-level FGM stepped beam and a five-level FGM stepped beam,are considered,and their natural frequencies and mode shapes are *** demonstrate the validity of the method in this paper,the simulation results by ABAQUS are also *** this basis,the detailed parametric analyses on the frequencies and dynamic responses of the three-level FGM stepped beam are carried *** results show the accuracy and efficiency of the TMM.

关键词： transfer matrix method(TMM) free vibration forced vibration functionally graded material(FGM) stepped beam

Asymmetric Reduction of Aromatic Ketones Catalyzed by Using (αs,4s)-2-Dichloromethyl-4,5-Dihydro-α-(4-Nitrophenyl)-4- Oxazolemethanol-Borane Complex

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 113-116页

作者： Shi Yu, hu quan-yuan, Yang Shao-rong, hu Xian-ming College of Pharmacy, Wuhan University, Wuhan 430072, hubei, China College of Pharmacy Wuhan University Wuhan Hubei China

Chiral oxazoborolidine borane complex was prepared from (αs, 4s)-2-dichloromethyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol with Borane in THF. The borane modified by chiral oxazoborolidine enantioselectively reduced aromatic ketones to second-alcohol with about 95%yield and medium optical yields. In the end of article, results are discussed and reduction mechanism is shown which proves the resulting major isomers fit very well.

关键词： asymmetric reduction prochiral ketones chiral oxazoborolidine borane chloramphenicol oxazoline

Aptamer-based Membrane Protein Analysis and Molecular Diagnostics

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Chemical Research in Chinese Universities 2024年第2期40卷 173-189页

作者： ZHAO Long hu Haolan MA Xiaoqian LYU Yifan yuan quan TAN Weihong Molecular Science and Biomedicine Laboratory(MBL) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of BiologyCollege of Chemistry and Chemical EngineeringAptamer Engineering Center of Hunan ProvinceHunan UniversityChangsha410082P.R.China The Cancer Hospital of the University of Chinese Academy of Sciences(Zhejiang Cancer Hospital) Hangzhou Institute of Medicine(HIM)Chinese Academy of SciencesHangzhou310022P.R.China Institute of Molecular Medicine(IMM) Renji HospitalSchool of MedicineCollege of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240P.R.China Furong Laboratory Changsha410082P.R.China

Membrane proteins are vital components of the cell membrane and play crucial roles in various cellular *** of membrane proteins is of paramount importance for studying molecular events inside cells and organisms and holds promising prospects for early disease diagnosis and treatment *** from obvious merits including high affinity,high specificity and ease of modification,aptamers have been regarded as ideal molecular recognition elements in membrane protein analysis and molecular diagnostics *** review summarised recent advances in membrane protein-specific aptamer screening,aptamer-based static and dynamic membrane protein analysis,and aptamer-based molecular diagnostic *** and challenges were also discussed.

关键词： Membrane protein Aptamer DNA nanotechnology Bioanalysis Molecular diagnostics

A Multi-Strategy-Improved Northern Goshawk Optimization Algorithm for Global Optimization and Engineering Design

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Computers, Materials & Continua 2024年第7期80卷 1677-1709页

作者： Liang Zeng Mai hu Chenning Zhang quan yuan Shanshan Wang School of Electrical and Electronic Engineering Hubei University of TechnologyWuhan430068China hubei Key Laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of TechnologyWuhan430068China

Optimization algorithms play a pivotal role in enhancing the performance and efficiency of systems across various scientific and engineering *** enhance the performance and alleviate the limitations of the Northern Goshawk Optimization(NGO)algorithm,particularly its tendency towards premature convergence and entrapment in local optima during function optimization processes,this study introduces an advanced Improved Northern Goshawk Optimization(INGO)*** algorithm incorporates a multifaceted enhancement strategy to boost operational ***,a tent chaotic map is employed in the initialization phase to generate a diverse initial population,providing high-quality feasible ***,after the first phase of the NGO’s iterative process,a whale fall strategy is introduced to prevent premature convergence into local *** is followed by the integration of T-distributionmutation strategies and the State Transition Algorithm(STA)after the second phase of the NGO,achieving a balanced synergy between the algorithm’s exploitation and *** research evaluates the performance of INGO using 23 benchmark functions alongside the IEEE CEC 2017 benchmark functions,accompanied by a statistical analysis of the *** experimental outcomes demonstrate INGO’s superior achievements in function optimization ***,its applicability in solving engineering design problems was verified through simulations on Unmanned Aerial Vehicle(UAV)trajectory planning issues,establishing INGO’s capability in addressing complex optimization challenges.

关键词： Northern Goshawk Optimization tent chaotic map T-distribution disturbance state transition algorithm UAV path planning

Bio-soft matter derived from traditional Chinese medicine:Characterizations of hierarchical structure,assembly mechanism,and beyond

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Journal of Pharmaceutical Analysis 2024年第6期14卷 823-839页

作者： Guiya Yang Yue Liu Yuying hu Yue yuan Yunan Qin quan Li Shuangcheng Ma School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing102488China Institute for Control of Chinese Traditional Medicine and Ethnic Medicine National Institutes for Food and Drug ControlBeijing100050China Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine School of Chinese Materia MedicaTianjin University of Traditional Chinese MedicineTianjin301617China Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan430062China

Structural and functional explorations on bio-soft matter such as micelles,vesicles,nanoparticles,aggregates or polymers derived from traditional Chinese medicine(TCM)has emerged as a new topic in the field of *** discovery of such cross-scaled bio-soft matter may provide a unique perspective for unraveling the new effective material basis of TCM as well as developing innovative medicine and *** the rapid rise of TCM-derived bio-soft matter,their hierarchical structure and assembly mechanism must be unambiguously probed for a further in-depth understanding of their pharmacological *** this review,the current emerged TCM-derived bio-soft matter assembled from either small molecules or macromolecules is introduced,and particularly the unambiguous elucidation of their hierarchical structure and assembly mechanism with combined electron microscopic and spectroscopic techniques is *** pros and cons of each technique are also *** future challenges and perspective of TCM-derived bio-soft matter are outlined,particularly the requirement for their precise in situ structural determination is highlighted.

关键词： Electron microscopy Spectroscopy Traditional Chinese medicine Bio-soft matter Structural characterization

Synthesis of Chiral Amino Cyclic Phosphoric Acids

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Wuhan University Journal of Natural Sciences 2000年第4期5卷 497-499页

作者： Zhang Zhan, hu quan-yuan, Deng Fa-da, Shu Jia-you, He Jian-she, hu Xian-ming College of Chemistry and Environmental Science, Wuhan University, Wuhan 430072 College of Chemistry and Environmental Science Wuhan UniversityWuhan 430072

Chiral amino cyclic phosphoric acids, 5-amino-2-hydroxy-4-(4-nitrophenyl)-1,3,2-dioxaphosphorinane 2-oxide and 2-hydroxy-4-(4-methylsulfonylphenyl)-5-phthalimido-1,3,2-dioxaphos phorinane 2-oxide are synthesized in good over yields (64.2%and 72.8%respectively) from 2-amino-1-aryl-1,3-propanediols. The different reaction conditions are necessary in hydrolysis reactions of amino cyclic phosphonyl chlorides.

关键词： chiral amino cyclic phosphoric acid amino diols synthesis

Analysis of lymph node metastasis and survival prognosis in early gastric cancer patients: A retrospective study

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1637-1646页

作者： Dong-yuan Liu Jin-Jin hu Yong-quan Zhou Ai-Rong Tan Department of General Surgery The 971st Hospital of Chinese People's Liberation ArmyQingdao 266071Shandong ProvinceChina Department of Chest Surgery Feicheng People's HospitalFeicheng 271600Shandong ProvinceChina Department of Gastrointestinal Surgery Zhongshan Hospital of Fudan UniversityShanghai 200032China Department of Oncology Qingdao Municipal HospitalQingdao 266000Shandong ProvinceChina

BACKGROUND Early gastric cancer(EGC)is a common malignant tumor of the digestive system,and its lymph node metastasis and survival prognosis have been *** retrospectively analyzing the clinical data of EGC patients,we can better under-stand the status of lymph node metastasis and its impact on survival and *** To evaluate the prognosis of EGC patients and the factors that affect lymph node METHODS The clinicopathological data of 1011 patients with EGC admitted to our hospital between January 2015 and December 2023 were collected in a retrospective cohort *** were 561 males and 450 *** mean age was 58±11 *** patient underwent radical *** status of lymph node metastasis in each group was determined according to the pathological examination results of surgical *** outcomes were as follows:(1)Lymph node metastasis in EGC patients;(2)Analysis of influencing factors of lymph node metastasis in EGC;and(3)Analysis of prognostic factors in patients with *** distributed measurement data are expressed as mean±SD,and a t test was used for comparisons between *** data are expressed as absolute numbers or percentages,and the chi-square test was used for comparisons between *** data were compared using a nonparametric rank sum test.A log-rank test and a logistic regression model were used for univariate analysis.A logistic stepwise regression model and a Cox stepwise regression model were used for multivariate *** Kaplan-Meier method was used to calculate the survival rate and construct survival curves.A log-rank test was used for survival *** Analysis of influencing factors of lymph node metastasis in *** results of the multifactor analysis showed that tumor length and diameter,tumor site,tumor invasion depth,vascular thrombus,and tumor differentiation degree were independent influencing factors for lymph node metastasis in patients with EGC(odds ratios=1.80,1.49,2.6

关键词： Gastric neoplasms Lymph node metastasis Prognosis Influencing factor Retrospective study

Numerical simulation of transient characteristics in a bulb turbine during the load rejection process

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Journal of Hydrodynamics 2024年第1期36卷 170-183页

作者： Yue Lu Yu-quan Zhang Zhong-wei He yuan Zheng College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China huadong Engineering Corporation Ltd. Hangzhou311122China

To evaluate the safety of the bulb tubular turbine,the dynamic hydraulic characteristics of a hydropower station system during the load rejection process are studied through numerical simulations and a prototype *** the developed model,a dynamic grid technology(DGT)controls the closure of the guide vane and the blade,whilst the moment balance equation and the user-defined function(UDF)provide the runner’s rotation *** 3-D transient simulation method can well predict the rotation speed and mass flow curves in the state of load *** simulation outcomes of the system performance are basically consistent with the measurement data of the *** observed,the runner is subjected to the reversely increased torque and axial force,the system is in a braking phase,and the maximum speed peaks at 144.6%of the rated ***,the internal flow of the runner is greatly affected by the closure of the guide vane,and the draft tube forms an eccentric spiral vortex *** breaks downstream,aggravating the instability of the draft ***,the transient characteristics span for the first five seconds,demonstrating the importance of establishing an efficient governing *** obtained results are useful for designing the turbine’s flow channel with a double regulating function and comprehending the turbine’s transient characteristics.

关键词： Bulb tubular turbine load rejection numerical simulation dynamic grid prototype test

Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of Forestry Research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan Liu yuan Zhu Jiayi Li Ying Ruan Xiankui quan Chuankuan Wang Xingchang Wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers