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Super-harmonic resonance of gear transmission system under stick-slip vibration in high-speed train

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Journal of Central South University 2017年第3期24卷 726-735页

作者： huang Guan-hua XU si-si ZHANG Wei-hua YANG Cai-jin State Key Laboratory of Traction Power （Southwest Jiaotong University） Chengdu 61003 I China Beijing Haidongqing Electrical and Mechanical Equipment Co. Ltd Beijing 101300 China CRRC Institute Co. Ltd Beiiing 100070 China

This work deals with super-harmonic responses and the stabilities of a gear transmission system of a high-speed train under the stick-slip oscillation of the *** dynamic model of the system is developed with consideration on the factors including the time-varying system stiffness,the transmission error,the tooth backlash and the self-excited excitation of the *** frequency-response equation of the system at super-harmonic resonance is obtained by the multiple scales method,and the stabilities of the system are analyzed using the perturbation *** nonlinear behaviors of the system including multi-valued solutions,jump phenomenon,hardening stiffness are *** effects of the equivalent damping and the loads of the system under the stick-slip oscillation are *** shows that the change of the load can obviously influence the resonance frequency of the system and have little effect on the steady-state response amplitude of the *** damping of the system has a negative effect,opposite to the *** synthetic damping of the system composed of meshing damping and equivalent damping may be less than zero when the wheel-set has a large slippage,and the system loses its stability owing to the Hopf *** results are validated by numerical simulations.

关键词： stick-slip vibration super-harmonic resonance Hopf bifurcation gear transmission system high-speed train

Study on the Effects and Influencing Factors of the Economic Spatial Correlation Network in the Yellow River Basin

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Journal of Systems Science and Information 2024年第5期12卷 690-708页

作者： Renquan huang Qian ZENG Yinong si School of Economy and Finance Xi’an International Studies UniversityXi’an 710128China

This paper constructs high-quality development assessment indicators based on the perspective ternary system,including economic development,technological innovation,and ecological environment *** on the data of 51 regions in the Yellow River Basin from 2010 to 2021,the economic spatial correlation relationships were *** using social network analysis and the QAP method,the economic spatial correlation characteristics and the influencing factors are *** results show that:1)The regions exhibit significant variations in comprehensive quality and economic ***,Xi’an,Jinan,Luoyang,and Zibo are the top five *** with high comprehensive quality tend to have stronger economic *** economic links show an obvious“upstream-midstream-downstream”three-tier structure.2)Regions such as Xi’an,Zhengzhou,Jinan,Taiyuan,Ordos,Luoyang,Baotou etc.,exhibit high degree and betweenness centrality,and low closeness *** are the core regions of high-quality development in the Yellow River *** I is the core block and spills to Block II,Block III,and Block *** II plays an essential bridge role to Block III.3)The factors of spatial adjacency,fixed asset investment,employment,informatization,and innovation are key to spatial correlation,and explain 40.5%of the spatial correlation.

关键词： Yellow River Basin spatial correlation social network analysis QAP regression

Research advancement of DNA-based intelligent hydrogels:Manufacture, characteristics, application of disease diagnosis and treatment

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Chinese Chemical Letters 2024年第10期35卷 92-101页

作者： Zhe-Han Yang Jie Yin Lei Xin Yuanfang Li Yijie huang ruo Yuan Ying Zhuo Chongqing Key Laboratory of Catalysis and Functional Organic Molecules College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China Key Laboratory of Luminescence and Real-Time Analytic Chemistry(Southwest University) Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

DNA-based hydrogels are exceptional materials for biological applications because of their numerous advantages such as biodegradability,biocompatibility,hydrophilicity,super absorbency,porosity,and *** these advantages,the ability of DNA-based hydrogels to respond to specific physical and chemical triggers and undergo reversible phase transitions has garnered significant attention in the fields of disease diagnosis(biosensors)and treatment(drug delivery).This article focuses on the recent advancements in the research of DNA-based hydrogels and discusses the different types of these hydrogels,the synthetic methods,their unique properties,and their applications in biosensors and drug *** types of DNA hydrogels are categorized based on their building blocks,and the process of synthesis as well as the unique characteristics of DNA-based hydrogels are ***,DNA-based responsive hydrogels utilized as intelligent materials for the development of biosensors are ***,this article also presents the current status of DNA-based responsive hydrogels in drug delivery for cancer treatment,wound healing,and other therapeutic ***,this paper discusses the current challenges in expanding the practical application of DNA-based hydrogels.

关键词： DNA-based hydrogel Intelligent hydrogel Manufacture Characteristics Diseasediagnosis and treatment

Clinical features and changes of disease spectrum of zoneⅡretinopathy of prematurity:a 10-year review

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International Journal of Ophthalmology(English edition) 2020年第11期13卷 1753-1757页

作者： Ying-Qin Ni si-si Xu Ting Zhang Xin huang Department of Ophthalmology Eye&ENT Hospital of Fudan UniversityShanghai 200031China Shanghai Key Laboratory of Visual Impairment and Restoration Shanghai 200031China

AIM:To report the clinical features and evolution of zoneⅡretinopathy of prematurity(ROP).METHODS:RetCam images of preterm infants with zoneⅡROP at our hospital between January 2009 and January 2019 were *** location,extent,and severity of ROP were *** were classified as typeⅠzoneⅡ,type 2 zoneⅡ,and mild zoneⅡ*** clinical features and evolution of zoneⅡROP were ***:In total,184 infants(302 eyes)were *** these,55 eyes(18%)developed typeⅠzoneⅡROP,39 eyes(13%)developed type 2 zoneⅡROP,and 208 eyes(69%)developed mild zoneⅡ*** proportion of typeⅠzoneⅡROP significantly decreased over the *** onset of type 2 zoneⅡand mild zoneⅡROP were Iwk earlier than typeⅠzoneⅡ,and both regressed at *** neovascular tuft(popcorn)and double track signs were characteristic manifestations of zoneⅡ***-seven percent of typeⅠzoneⅡROP regressed completely with an unfavorable outcome that emerged in seven eyes after laser ***:ZoneⅡis an area with ROP disease at various risk ***ⅡROP has unique clinical presentations like popcorn and double track *** time,the proportion of zoneⅡROP with high risk gradually decrease and respond well to therapy.

关键词： retinopathy of prematurity classification natural evolution zone

Epitaxial thin film of SmFeO_3 ferroelectric heterostructures

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Science China Chemistry 2014年第6期57卷 803-806页

作者： si WenZhe huang KeKe WU XiaoFeng FENG ShouHua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University

Epitaxial growth of SmFeO3/Srruo3 was achieved on SrTiO3 substrates by the pulsed laser deposition(PLD)method at 973 K under oxygen partial pressure of 12.5 *** Fe2+leakage was detected in our SmFeO3 *** remanent polarization and coercive electric field of the thin film with a higher degree of orientation along(110)were 1.97μC/cm2 and 0.89×104 V/cm at room temperature,*** film showed enhanced canted antiferromagnetism spin ordering compared with its corresponding powder materials.

关键词： ferroelectric materials thin films solid-oxide

Water-lifting and aeration system improves water quality of drinking water reservoirs: Biological mechanism and field application

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Journal of Environmental Sciences 2023年第7期129卷 174-188页

作者： Liqing Kou Tinglin huang Haihan Zhang Kai Li Fengyao Hua Cheng huang Xiang Liu Fan si Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province Xi’an 710055China

Reservoirs have been served as the major source of drinking water for dozens of *** water quality safety of large andmedium reservoirs increasingly becomes the focus of public *** test has proved that water-lifting and aeration system(WLAS)is a piece of effective equipment for in situ control and improvement of water ***,its intrinsic bioremediation mechanism,especially for nitrogen removal,still lacks in-depth ***,the dynamic changes inwater quality parameters,carbon source metabolism,species compositions and co-occurrence patterns ofmicrobial communitieswere systematically studied in Jinpen Reservoir within a wholeWLAS running *** operation could efficiently reduce organic carbon(19.77%),nitrogen(21.55%)and phosphorus(65.60%),*** analysis revealed that the microbialmetabolic capacitieswere enhanced viaWLAS operation,especially in ***-throughput sequencing demonstrated that WLAS operation altered the diversity and distributions of microbial communities in the source *** most dominant genus accountable for aerobic denitrification was identified as ***,network analysis revealed that microorganisms interacted more closely through WLAS ***-reduction potential(ORP)and total nitrogen(TN)were regarded as the two main physicochemical parameters influencing microbial community structures,as confirmed by redundancy analysis(RDA)and Mantel ***,the results will provide a scientific basis and an effective way for strengthening the in-situ bioremediation of micro-polluted source water.

关键词： Water-lifting and aeration system Drinking water reservoir Co-occurrence network Biological mechanism

Contribution of winter fluxes to the annual CH_4, CO_2 and N_2O emissions from fres hwater marshes in the Sanjiang Plain

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Journal of Environmental Sciences 2006年第2期18卷 270-275页

作者： HAO Qing-ju WANG Yue-si SONG Chang-chun huang Yao Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Wetlands at the interface of the terrestrial and aquatic ecosystems are intensive sites for mineralization of organic matter, but the contribution of winter season fluxes of CH4, CO2 and N2O from wetland ecosystems to annual budgets is poorly known. By using the static opaque chamber and GC techniques, fluxes of CH4, CO2 and N2O at two freshwater marshes in the Sanjiang Plain were measured during the winter seasons of 2002/2003 and 2003/2004 with contrasting snow conditions and flooding regimes. The results showed that there were significant interannual and spatial differences in CH4, CO2 and N2O fluxes. The Carex lasiocarpa marsh emitted more CH4 and CO2 while absorbed less N2O than the Deyeuxia angustifolia marsh during the winter seasons. Over the winter season, emissions of CH4, CO2 and N2O ranged from 0.42 to 2.41 gC/m^2, from 24.13 to 50.16 gC/m^2, and from -25,20 to -148.96 mgN/m^2, respectively. The contributions of winter season CH4 and CO2 emission to the annual budgets were 2.32% 4.62% and 22.17%- 27.97%, respectively. Marshes uptake N2O during the freezing period, while release N2O during the thawing period. The winter uptake equaled to 13.70%-86.69% of the growing-season loss. We conclude that gas exchange between soil/snow and the atmosphere in the winter season contributed greatly to the annual budgets and cannot be ignored in a cool temperate freshwater marsh in Northeast China.

关键词： freshwater marsh winter flux greenhouse gas emission Sanjiang Plain

Strong Convergence by the Shrinking Projection Method for a Generalized Equilibrium Problems and Hemi-Relatively Nonexpansive Mappings

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Journal of Mathematical Research and Exposition 2010年第6期30卷 1099-1107页

作者： ruo Feng RAO Jia Lin huang Department of Mathematics Yibin UniversitySichuan 644007P.R.China

Motivated by the recent result obtained by Takahashi and Zembayashi in 2008,we prove a strong convergence theorem for finding a common element of the set of solutions of a generalized equilibrium problem and the set of fixed points of a hemi-relatively nonexpansive mapping in a Banach space by using the shrinking projection *** main results obtained in this paper extend some recent results.

关键词： hemi-relatively nonexpansive mapping generalized equilibrium problem α-inversestrongly monotone mapping.

CONTRIBUTION OF CHOLESTEROL MOIETIES ATTACHED ON MPEG-b-PCL-b-PLL TO THE CELL UPTAKE, ENDOSOMAL ESCAPE AND GENE KNOCKDOWN OF THE MICELLEPLEXES OF siRNA

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Chinese Journal of Polymer Science 2013年第6期31卷 912-923页

作者： ruo-gu Qi Su-hong Wu Yu Wang Jie Chen Zhi-gang Xie Yu-bin huang 景遐斌 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

To further enhance the transfection efficiency of a micelleplex system based on monomethoxy poly（ethylene glycol）-block-poly（e-caprolactone）-block-poly（L-lysine）（MPEG-b-PCL-b-PLL）, cholesterol （Chol） moieties are attached to the e-termini of PLL segments to obtain MPEG-b-PCL-b-PLL/Chol. The structure and morphology of the copolymer are studied by IH-NMR, TEM and DLS （dynamic light scattering）. The cytotoxicity, cell uptake, endosomal release and mRNA knockdown are studied by MTT （3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide） assay, flow cytometry, CLSM （confocal laser scanning microscopy） and RT-PCR （real-time polymerase chain reaction）. The results show that compared to their precursor MPEG-b-PCL-b-PLL, the cholesterol-grafted copolymer shows significantly lower toxicity, more rapid cellular endocytosis and endosome escape, and consequently displays enhanced siRNA transfection efficiency even at a lower N/P ratio. These improvements are ascribed to enhanced interaction of the cholesterol moieties with both cellular membrane and endosomal membrane. Moreover, effect of the PLL block length is examined. The final conclusion is that long enough PLL segments and incorporation of proper fraction of cholesterol onto the PLL segments benefit the enhancement of siRNA transfection efficiency.

关键词： Amphiphilic copolymer Cholesterol Endosome escape Micelleplex siRNA delivery.