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Chinese Journal of Aeronautics 2024年第2期37卷 360-370页

作者： yu lu Baozeng yuE Bailong HAO Bole MA feng LIU yuanyuan CHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

In the process of stage separation of recoverable liquid launch vehicles,because of the large amount of residual fuel in the storage tanks,the influence of liquid sloshing on separation safety must be *** calculation simplicity and operation practicability,the Moving Pulsating Ball Model(MPBM)of large amplitude liquid sloshing is introduced into the calculation of launch vehicle stage *** the dynamic equation of the model with the energy relationship during"breathing movement",the formula calculating the force of liquid on the rigid body is *** with the calculations of commercial CFD calculation software,the accuracy of MPBM model is ***,all the external forces and moments are applied to the rigid body of the stages,so that the translational and rotational dynamic equations of the stages are obtained *** to the relative position of the two stages,the geometric shape of the interstage section and the engine of the second stage,the minimum clearance in the separation process can be decided to guarantee that the separation process is safe.

关键词： Moving Pulsating Ball Model(MPBM) Dynamics of stage separation Large amplitude sloshing Recoverable liquid launch vehicle Flight dynamics

An experimental and modeling study of n-hexadecane autoignition under low-to-intermediate temperatures

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Science China(Technological Sciences) 2020年第5期63卷 719-730页

作者： yu Liang WANG Wenyu WANG SiXu feng yuan QIAN Yong lu XingCai Key Laboratory for Power Machinery and Engineering of M.O.E. Shanghai Jiao Tong UniversityShanghai 200240China

N-hexadecane is a potential candidate of diesel surrogate fuels and is also the largest linear alkane(n-alkanes)with known chemical kinetic *** objective of this study is to investigate the autoignition characteristics of n-hexadecane in the lowto-intermediate temperature region and to validate the existing kinetic *** this study,the ignition delay times(IDTs)of nhexadecane were measured using a heated rapid compression machine(RCM)at two pressures of 7 and 10 bar,and over equivalence ratios ranging from 0.5 to ***-stage ignition characteristic and the negative temperature coefficient(NTC)behavior of total ignition delay time were experimentally *** study paid special attention to the influence of pressure,equivalence ratio,and oxygen content on the IDTs of *** is observed that both the total IDTs and the first-stage IDTs decrease with the rise of those *** is worth noting that the first-stage IDT is found to show a greater dependence on temperature but a weaker dependence on other parameters compared to the total *** observed IDT dependence in the lowtemperature region(LTR)were quantitatively described by ignition delay time *** newly measured IDTs were then validated against two kinetic models(LLNL and CRECK).Simulation results show that both models underpredict the first-stage IDT but generally capture the temperature *** CRECK model well predicts the total IDTs of n-hexadecane while the LLNL model significantly underpredicts the total IDTs at most investigated *** the best of our knowledge,this study is the first investigation on n-hexadecane autoignition under low-to-intermediate temperatures,which deepens the understanding of large n-alkane oxidation and contributes to the improvement of the existing kinetic models.

关键词： n-hexadecane autoignition rapid compression machine low-temperature reactivity ignition delay time kinetic model

Protein arginine methyltransferase-6 regulates heterogeneous nuclear ribonucleoprotein-F expression and is a potential target for the treatment of neuropathic pain

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Neural Regeneration Research 2025年第9期20卷 2682-2696页

作者： Xiaoyu Zhang yuqi Liu Fangxia Xu Chengcheng Zhou Kaimei lu Bin Fang Lijuan Wang Lina Huang Zifeng Xu Department of Anesthesiology International Peace Maternity and Child Health HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Anesthesiology Shanghai General HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Shanghai Key Laboratory of Embryo Original Diseases ShanghaiChina

Protein arginine methyltransferase-6 participates in a range of biological functions,particularly RNA processing,transcription,chromatin remodeling,and endosomal ***,it remains unclear whether protein arginine methyl transferase-6 modifies neuropathic pain and,if so,what the mechanisms of this *** this study,protein arginine methyltransferase-6 expression levels and its effect on neuropathic pain were investigated in the spared nerve injury model,chronic constriction injury model and bone cancer pain model,using immunohistochemistry,western blotting,immunoprecipitation,and label-free proteomic *** results showed that protein arginine methyltransferase-6 mostly co-localized withβ-tubulinⅢin the dorsal root ganglion,and that its expression decreased following spared nerve injury,chronic constriction injury and bone cancer *** addition,PRMT6 knockout(Prmt6~(-/-))mice exhibited pain ***,the development of spared nerve injury-induced hypersensitivity to mechanical pain was attenuated by blocking the decrease in protein arginine methyltransferase-6 ***,when protein arginine methyltransferase-6 expression was downregulated in the dorsal root ganglion in mice without spared nerve injury,increased levels of phosphorylated extracellular signal-regulated kinases were observed in the ipsilateral dorsal horn,and the response to mechanical stimuli was ***,protein arginine methyltransferase-6 appeared to contribute to spared nerve injury-induced neuropathic pain by regulating the expression of heterogeneous nuclear ***,protein arginine methyltransfe rase-6-mediated modulation of hete rogeneous nuclear ribonucleoprotein-F expression required amino atids 319 to 388,but not classical H3R2 *** findings indicated that protein arginine methyltransferase-6 is a potential therapeutic target fo r the treatment of peripheral neuro pathic pain.

关键词： dorsal root ganglion heterogeneous nuclear ribonucleoprotein F neuropathic pain protein arginine methyltransferase-6 sensory neurons

Living Crystallization-Driven Self-Assembly of Oligo(p-phenylene vinylene)-Containing Block Copolymers:Impact of Branched Structure of Alkyl Side Chain ofπ-Conjugated Segment

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Chinese Journal of Polymer Science 2023年第4期41卷 574-584,I0008页

作者： Yang Song Bo Xiang Xiao-yu Huang Guo-Lin lu Chun feng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai200093China Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China

The structure of side chains ofπ-conjugated segments is a critical factor determining living crystallization-driven self-assembly(CDSA),a versatile platform to generate fiber-like nanostructures with precise length and ***,we design and synthesize three block copolymers(BCPs)containing same corona-forming poly(N-isopropyl acrylamide)(PNIPAM)segment,but different core-formingπ-conjugated oligo(p-phenylene vinylene)(OPV)with linear pentyl(l-OPV),racemic 2-methyl butyl(r-OPV)and stereo-regular chiral(S)-2-methyl butyl(c-OPV)side chains,*** using these BCPs of l-OPV-b-PNIPAM_(47),r-OPV-b-PNIPAM_(47)and c-OPV-b-PNIPAM_(47)as model,we aim to get a deep insight into how steric and stereo-regular effect induced by branched alkyl side chains of OPV segment affects the living *** results showed that l-OPV-b-PNIPAM_(47)exhibits typical characteristics of self-seeding and seeded growth of living CDSA to give uniform fiber-like micelles of controlled *** the contrary,r-OPV-b-PNIPAM_(47)and c-OPV-b-PNIPAM_(47)with branched racemic and stereo-regular chiral alkyl side chains are more prone to self-nucleation during the micellar elongation to give short and polydisperse fiber-like *** obvious selfnucleation during the micellar elongation of r-OPV-b-PNIPAM_(47)and c-OPV-b-PNIPAM_(47)is due to the increase of steric repulsion with OPV units induced by branched alkyl side chains,not the stereo-irregular effect of racemic alkyl side chains.

关键词： π-Conjugated polymer Nanofiber Living crystallization-driven self-assembly Structure effect

Heat-induced Internal Strain Relaxation and its Effect on the Microstructure of Polyacrylonitrile-based Carbon Fiber

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Journal of Materials Science & Technology 2014年第10期30卷 1051-1058页

作者： Denghua Li Chunxiang lu Gangping Wu yu Yang Zhihai feng Xiutao Li feng An Baoping Zhang National Engineering Laboratory for Carbon Fiber Technology Institute of Coal ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences National Key Laboratory of Advanced Functional Composite Materials Aerospace Research Institute of Materials & Processing Technology

The transformation of the internal strain and its effect on the microstructure of polyacrylonitrile-based carbon fiber during the high-temperature graphitization were investigated. The internal compressive strain within the carbon turbostratic structure was confirmed through a careful analysis by wide-angle X-ray diffraction and Raman spectroscopy. Heat-induced strain/stress relaxation along the fiber axis was observed and was found to have a profound effect on the structure of both the crystallites and microvoids. The results indicated that, the relaxation of residual strain changed the graphite layers from a wrinkled and distorted morphology to a straight and smooth one, and consequently led the crystallites to stack closely and orderly with increasing stack height. The strain relaxation also changed the morphology of crystallites and microvoids, resulting in an anisotropic growth for the latters.

关键词： Graphitizafion Internal strain Microstructures Nanocrystalline Carbon fiber

The RNF20/40 complex regulates p53-dependent gene transcription and mRNA splicing

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Journal of Molecular Cell Biology 2020年第2期12卷 113-124页

作者： Chen Wu Yaqi Cui Xiuhua Liu feng Zhang Lin-yu lu Xiaochun yu College of Life Sciences Hebei UniversityBaoding 071000China Department of Cancer Genetics and Epigenetics Beckman Research InstituteCity of HopeDuarteCA 91010USA College of Life and Environment Sciences Shanghai Normal UniversityShanghaiChina Key Laboratory of Reproductive Genetics Ministry of Education and Women's Reproductive Health Laboratory of Zhejiang ProvinceWomen's HospitalSchool of MedicineZhejiang UniversityHangzhouChina Institute of Translational Medicine Zhejiang UniversityHangzhouChina

p53 is a key transcription factor to regulate gene ***,the molecular mechanism of chromatin-associated p53 on gene transcription remains ***,using unbiased protein affinity purification,we found that the RNF20/40 complex associated with p53 on the *** analyses indicated that p53 mediated the recruitment of the RNF20/40 complex to p53 target gene loci including p21 and PUMA loci and regulated the transcription of p21 and PUMA via the RNF20/40 complex-dependent histone H2B ubiquitination(ubH2B).Lacking the RNF20/40 complex suppressed not only ubH2B but also the generation of the mature mRNA of p21 and ***,ubH2B was recognized by the ubiquitin-binding motif of pre-mRNA processing splicing factor 8(PRPF8),a subunit in the spliceosome,and PRPF8 was required for the maturation of the mRNA of p21 and *** study unveils a novel p53-dependent pathway that regulates mRNA splicing for tumor suppression.

关键词： RNF20 RNF40 gene transcription p53 p21 PUMA

CVD Micro-diamond Coated Tool Lapping with Sapphire Wafer

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第1期34卷 81-88页

作者： feng Wei lu Wenzhuang yu Yaping Yang Bin Zuo Dunvuen College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China College of Mechanical Engineering Yancheng Institute of TechnologyYancheng 224051P.R.China

Micro-diamond films were prepared on YG6 substrate by hot filament chemical vapor deposition *** innovative micro-diamond coated tool was used to the lap sapphire *** effect of load,rotating speed,and lapping time on material removal rate(MRR)and surface roughness was *** results showed that the best process parameters were 3N,100r/min and 15 *** surface quality of sapphire improved significantly after *** coating after lapping adhered well and did not show any *** innovative micro-diamond coated tool was feasible and suitable for the lapping of the single crystal sapphire wafer.

关键词： micro-diamond film sapphire surface roughness lapping

Establishing a cat model of chronic optic nerve compression injury

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Neural Regeneration Research 2009年第6期4卷 462-467页

作者： feng yu Shaoji yuan Rongwei Zhang Yicheng lu Meiqing Lou Department of Neurosurgery General Hospital of Jinan Military Area Command of Chinese PLA Jinan 250031 Shandong Province China Department of Neurosurgery Changzheng Hospital Second Military Medical University of Chinese PLA Shanghai 200003 China

BACKGROUND： An animal model of chronic optic nerve injury is necessary to further understand the pathological mechanisms involved. OBJECTIVE： To establish a stabilized, chronic, optic nerve crush model, which is similar to the clinical situation to explore histopathological and optic electrophysiological changes involved in this injury. DESIGN, TIME AND SETTING： A randomized and controlled animal trial was performed at Shanghai Institute of Neurosurgery from May to October 2004, MATERIALS： A BAL3XRAY undetachable balloon and Magic-BD catheter were provided by BLAT, France; JX-2000 biological signal processing system by Second Military Medical University of Chinese PLA, China; inverted phase contrast microscopy by Olympus, Japan. METHODS： A total of twenty normal adult cats were randomly assigned to control （n = 5） and model （n = 15） groups, according to different doses of contrast agent injected through balloons as follows： 0.2 mL injection, 0.25 mL injection, and 0.35 mL injection, with each group containing 5 animals. Imitating the clinical pterion approach, the optic nerves were exposed using micro-surgical methods. An engorged undetachable balloon was implanted beneath the nerve and connected to a catheter. Balloon size was controlled with a contrast agent injection （0.1 mL/10 min） to form an occupying lesion model similar to sellar tumors. MAIN OUTCOME MEASURES： The visually evoked potential examination was used to study optical electrophysiology changes in pre-post chronic optical nerve injury. Ultrastructural pathological changes to the optic nerve were analyzed by electron microscopy. RESULTS： During the early period （day 11 after modeling）, visually evoked potential demonstrated no significant changes. In the late period （day 51 after modeling）, recorded VEP demonstrated that P1 wave latency was prolonged and P1 wave amplitude was obviously reduced. Following injury, the endoneurium, myelin sheath, lamella, axolemma, and axon appeared disordered. CONCluSION

关键词： optic nerve injury evoked potential visual sensation feline disease models, animal

A multi-layer modelling approach for mining versatile ports of a global maritime transportation network

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International Journal of Digital Earth 2023年第1期16卷 2129-2151页

作者： Peng Peng Christophe Claramunt Shifen Cheng yu Yang feng lu State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China Naval Academy Research Institute Brest NavalFrance Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijingPeople’s Republic of China The Academy of Digital China Fuzhou UniversityFuzhouPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Giographical Information Resource Development and Application NanjingPeople’s Republic of China

International ports play critical roles in maintaining transportation flows and sustaining the effectiveness of global maritime *** the concept of versatile ports has been introduced to represent the specific patterns that these ports play at the regional and global levels,there is still a need for the design and development of computational approaches that support these *** paper introduces a flexible multi-layer network approach for an international maritime network whose interest is that it offers a flexible model that favours the identification of the different transportation flows and versatile *** model is complemented by a series of structural indices complemented by a new overlap measure that evaluates the specific role of a given port across various transportation *** whole approach is implemented and experimented with using massive AIS maritime data that supports the automatic generation of the multi-layer network,and derivation of the structural measures while maintaining a flexible view of the maritime *** experiments applied to the global maritime transportation network identify key versatile ports and highlight significant differences at the regional and trade flow levels.

关键词： Versatile port multilayer network aggregated network maritime transportation vessel trajectory data

A series of carbosilane dendrimers with acetyl end-group:From synthesis to their unique optical characteristics

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Chinese Chemical Letters 2009年第9期20卷 1085-1087页

作者： Wen Yan Sun Hai feng lu Deng Xu Wang Sheng yu feng School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China

A series of c arbosilane dendrimers with acetyl end-group were synthesized. Their structures were characterized by 1H NMR, IR, and MS, respectively. Then dendrimers were coordinated with lanthanide ions （Eu3＋ and Tb3＋, respectively）. The luminescence spectra of the complexes show narrow-width emissions in visible light region. 2009 Sheng yu feng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Synthesis Carbosilane dendrirner luminescence Lanthanide ions