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Flight characteristics Analysis Based on QAR Data of a Jet Transport During landing at a High-altitude Airport

chinese Journal of Aeronautics 2012年第1期25卷 13-24页

作者： c.edward lan WU Kaiyuan YU Jiang Department of Aerospace Engineering The University of KansasKansas 66045USA china Aerodynamics Research and Development center Mianyang 622661China Scientific Research Base Civil Aviation Flight University of ChinaGuanghan 618307China

Flight data of a twin-jet transport aircraft in revenue flight are analyzed for potential safety problems. Data from the quick access recorder （QAR） are first filtered through the kinematic compatibility analysis. The filtered data are then organized into longitudinal- and lateral-directional aerodynamic model data with dynamic ground effect. The dynamic ground effect requires the radio height and sink rate in the models. The model data are then refined into numerical models through a fuzzy logic algorithm without data smoothing in advance. These numerical models describe nonlinear and unsteady aerodynamics and are used in nonlinear flight dynamics simulation. For the jet transport under study, it is found that the effect of crosswind is significant enough to excite the Dutch roll motion. Through a linearized analysis in flight dynamics at every instant of time, the Dutch roll motion is found to be in nonlinear oscillation without clear damping of the amplitude. In the analysis, all stability derivatives vary with time and hence are nonlinear functions of state variables. Since the Dutch roll motion is not damped despite the fact that a full-time yaw damper is engaged, it is concluded that the design data for the yaw damper is not sufficiently realistic and the contribution of time derivative of sideslip angle to damping should be considered. As a result of nonlinear flight simulation, the vertical wind acting on the aircraft is estimated to be mostly updraft which varies along the flight path before touchdown. Varying updraft appears to make the descent rate more difficult to control to result in a higher g-load at touchdown.

关键词： jet transport unsteady aerodynamics nonlinear aerodynamics flight dynamics flight safety quick access recorder data

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A Scalable Pillar Layered Metal-Organic Framework for Natural Gas Purification

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chemical Research in chinese Universities 2024年第4期40卷 675-681页

作者： LU Nan lan lan GAO Qiang LI Na BU Xian-He School of Materials Science and Engineering Nankai UniversityTianjin300350P.R.China State Key Laboratory of Elemento-Organic chemistry College of ChemistryNankai UniversityTianjin300071P.R.China School of Environmental and chemical Engineering Jiangsu University of Science and TechnologyZhenjiang212003P.R.China

One-step harvest of high-purity methane(cH_(4))from ternary propane/ethane/methane(c_(3)H_(8)/c_(2)H_(6)/cH_(4))mixtures remains a desirable yet challenging goal for natural gas ***,adsorbents either suffer from high capacity and selectivity,or are caught in a dilemma of scalable ***,we demonstrate a scalable pillar layered metal-organic framework Ni-MOF for highly efficient one-step cH_(4)***-MOF exhibits high c_(2)H_(6)and c_(3)H_(8)uptakes of 83.3 and 86.1 cm^(3)/g at 298 K and 100 kPa and remarkable c_(2)H_(6)/cH_(4)(50/50,volume ratio,21.5)and c_(3)H_(8)/cH_(4)(50/50,volume ratio,212.0)***,high c_(2)H_(6)(42.2 cm^(3)/g at 10 kPa)and c_(3)H_(8)(64.7 cm^(3)/g at 5 kPa)capacities in the low-pressure region at 298 K were realized on Ni-MOF,suggesting the strong affinities of Ni-MOF towards c_(2)H_(6)and c_(3)H_(8).Furthermore,the dynamic breakthrough experiments revealed that purifying cH_(4)from natural gas in one-step can be achieved in Ni-MOF with high-purity(>99.8%)and productivity(346.0 cm^(3)/g).Most significantly,the production of Ni-MOF can be scalably synthesized at room temperature,rendering it promising potential for industrial *** combined advantages of exceptional separation performance,scalability,and cycle stability of Ni-MOF pave the way for one-step cH_(4)purification from natural gas.

关键词： Metal-organic framework Adsorption and separation Natural gas purification Scale-up synthesis

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Direct conversion of Methane to Propylene

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Research 2024年第2期2023卷 463-472页

作者： Yunpeng Hou Yuxiang lan chao Qian Shaodong Zhou college of chemical and Biological Engineering Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyZhejiang University310027 HangzhouP.R.China Zhejiang Provincial Innovation center of Advanced chemicals Technology Institute of Zhejiang University-Quzhou324000 QuzhouP.R.China

Nonoxidative coupling of methane exhibits promising prospect in that it affords value-added hydrocarbons and hydrogen with high atom ***,challenge remains in direct,selective conversion of methane to more valuable hydrocarbons like *** current work presents a catalyst with well-dispersed Ta atoms anchored by graphitic c_(3)N_(4)-supported *** a catalyst is able to convert methane selectively to ethylene and propylene at a relatively low temperature(350℃).The conception of the active center and construction of the catalyst have been described,and the origins of the catalytic performance are discussed.

关键词： methane catalyst hydrocarbons

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coupling Effect of cryogenic Freeze-Thaw cycles and chloride Ion Erosion Effect in Pre-cracked Reinforced concrete

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Structural Durability & Health Monitoring 2024年第3期18卷 255-276页

作者： Yang Li Sibo Jiang Ruixin lan School of civil Engineering and Architecture Hubei University of TechnologyWuhan430068China

chloride (cl−) ion erosion effects can seriously impact the safety and service life of marine liquefied natural gas(LNG) storage tanks and other polar offshore structures. This study investigates the impact of different low-temperaturecycles (20°c, –80°c, and −160°c) and concrete specimen crack widths (0, 0.3, and 0.6 mm) on the cl−ion diffusion performance through rapid erosion tests conducted on pre-cracked concrete. The results show thatthe minimum temperature and crack width of freeze-thaw cycles enhance the erosive effect of chloride ions. Thecl− ion concentration and growth rate increased with the increasing crack width. Based on the experimental modeland in accordance with Fick’s second law of diffusion, the cl− ion diffusion equation was modified by introducingcorrection factors in consideration of the freeze-thaw temperature, crack width, and their coupling *** experimental and fitting results obtained from this model can provide excellent reference for practical engineeringapplications.

关键词： chloride ions freeze-thaw cycles cracks

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The completeness of Accreting Neutron Star Binary candidates from the chinese Space Station Telescope

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Research in Astronomy and Astrophysics 2024年第9期24卷 30-38页

作者： Hao Shen Shun-Yi lan Xiang-cun Meng Yunnan Observatories Chinese Academy of Sciences University of chinese Academy of Sciences International centre of Supernovae Yunnan Key Laboratory

A neutron star（NS） has many extreme physical conditions, and one may obtain some important information about an NS via accreting neutron star binary（ANSB） systems. The upcoming chinese Space Station Telescope（cSST）provides an opportunity to search for a large sample of ANSB candidates. Our goal is to check the completeness of the potential ANSB samples from cSST data. In this paper, we generate some ANSBs and normal binaries under the cSST photometric system by binary evolution and binary population synthesis method and use a machine learning method to train a classification model. Although the Precision（94.56%） of our machine learning model is as high as before study, the Recall is only about 63.29%. The Precision/Recall is mainly determined by the mass transfer rate between the NSs and their companions. In addition, we also find that the completeness of ANSB samples from cSST photometric data by the machine learning method also depends on the companion mass and the age of the system. ANSB candidates with a low initial mass companion star（0.1 M⊙to 1 M⊙） have a relatively high Precision（94.94%） and high Recall（86.32%）, whereas ANSB candidates with a higher initial mass companion star（1.1 M⊙to 3 M⊙） have similar Precision（93.88%） and quite low Recall（42.67%）. Our results indicate that although the machine learning method may obtain a relatively pure sample of ANSBs, a completeness correction is necessary for one to obtain a complete sample.

关键词： methods: analytical stars: neutron X-rays: binaries

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Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in climate change Research 2024年第3期15卷 442-451页

作者： Jian-Sheng HAO Yan WANG lan-Hai LI Key Laboratory of land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China cAS Research center for Ecology and Environment of central Asia Urumqi 830011China

climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°c per decade(pcover duration was observed to have been shortened by 4.77 d per decade(pch is characterised by later snow-cover onset and earlier ***,average and maximum snow depths increased along with an increase in peak snow water equivalent,thus indicating a higher frequency of extremely scarce or abundant snow *** low snowpack temperature gradient and earlier snowmelt dates in spring lead to earlier occurrences of snowmelt floods and wet *** the risks of these events increase,they pose greater threats to farmlands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： climate change Snowpack variations Snow-related disaster Tianshan Mountains

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Bioinspired supramolecular macrocycle hybrid membranes with enhanced proton conductivity

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Nano Research 2024年第2期17卷 797-805页

作者： Pengfei Yang Linlin Xu Panagiotis Trogadas Marc-Olivier coppens Yang lan centre for Nature Inspired Engineering Department of Chemical EngineeringUniversity College LondonLondon WC1E 7JEUK

Enhancing the proton conductivity of proton exchange membranes(PEMs)is essential to expand the applications of proton exchange membrane fuel cells(PEMFcs).Inspired by the proton conduction mechanism of bacteriorhodopsin,cucurbit[n]urils(cB[n],where n is the number of glycoluril units,n=6,7,or 8)are introduced into sulfonated poly(ether ether ketone)(SPEEK)matrix to fabricate hybrid PEMs,employing a nature-inspired chemical engineering(NIcE)*** carbonyl groups of cB[n]act as proton-conducting sites,while the host–guest interaction between cB[n]and water molecules offers extra protonconducting ***,the molecular size of cB[n]aids in their dispersion within the SPEEK matrix,effectively bridging the unconnected proton-conducting sulfonic group domains within the SPEEK ***,all hybrid membranes exhibit significantly enhanced proton ***,the SPEEK membrane incorporating 1 wt.%cB[8](cB[8]/SPEEK-1%)demonstrates the highest proton conductivity of 198.0 mS·cm^(−1) at 60°c and 100%relative humidity(RH),which is 228%greater than that of the pure SPEEK membrane under the same ***,hybrid membranes exhibit superior fuel cell *** cB[8]/SPEEK-1%membrane achieves a maximum power density of 214 mW·cm^(−2),representing a 140%improvement over the pure SPEEK membrane(89 mW·cm^(−2))at 50°c and 100%*** findings serve as a foundation for constructing continuous proton-conducting pathways within membranes by utilizing supramolecular macrocycles as fuel cell electrolytes and in other applications.

关键词： supramolecular macrocycle proton conductivity cucurbit[n]uril proton exchange membrane fuel cell

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Taphonomy and Paleoecology of Lycoptera: A case Study from the Lower Jehol Group in Western Liaoning, Northeastern china

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Journal of Earth Science 2024年第3期35卷 737-746页

作者： Zhongwu lan Rong cao Shujing Zhang State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430078China college of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geology Trinity CollegeDublin 999015Ireland

Taphonomy and paleoecology(biological behavior)of the Early cretaceous fish fossils are poorly *** study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Mesozoic strata of western Liaoning Province,NE *** XRD analysis shows that gismondine is the dominant clay minerals that could have contributed to the preservation of Lycoptera fossils and microbial mat fragments in the fossil-bearing *** may have formed under volcanism-related hydrothermal regime that was transformed from crystal and lithic ***μ-XRF imaging analysis shows a dominant chemical composition of Al,Si,P,S,Rh,K,ca,Ti,c,cr,Mn,Fe,Ni,among which P,ca,c and S are enriched in the fish skeleton in comparison to the *** suggests a dominant apatite composition for the fish *** influence did not smear off these organic signals probably because of protection of *** coexistance of c and S with Ni is assumed to represent recovered primary productivity following volcanic explosions and toxic gas *** head of juvenile fish stays close to the body of adult *** further discoveries,such phenomenon is interpreted to suggest that adult fish actively protected juvenile fish in the presence of environmental pressures such as anoxia and deterioration of water quality induced by *** acidification and hypoxia in association with volcanism created a harmful environment causing mass extinction of *** adult Lycoptera protected their juveniles by its body at the moment before *** biological behavior will be increasingly reported given the wide occurrence of Lycoptera in Mesozoic strata.

关键词： Lycoptera taphonomy paleoecology fish Jehol Group NE china.

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Emerging mechanisms and implications of c GAS-STING signaling in cancer immunotherapy strategies

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cancer Biology & Medicine 2024年第1期21卷 45-64页

作者： Jiawen Zhang Sihui Yu Qiao Peng Ping Wang lan Fang Tongji University cancer center Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Reproductive Medicine center Department of Obstetrics and GynecologyShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201620China Department of Obstetrics and Gynecology Zhongshan HospitalFudan UniversityShanghai 200032China

The intricate interplay between the human immune system and cancer development underscores the central role of immunotherapy in cancer *** this landscape,the innate immune system,a critical sentinel protecting against tumor incursion,is a key *** cyclic GMP-AMP synthase(c GAS)and stimulator of interferon genes(STING)pathway has been found to be a linchpin of innate immunity:activation of this signaling pathway orchestrates the production of type I interferon(IFN-α/β),thus fostering the maturation,differentiation,and mobilization of immune effectors in the tumor ***,STING activation facilitates the release and presentation of tumor antigens,and therefore is an attractive target for cancer *** strategies to activate the STING pathway,including use of pharmacological agonists,have made substantial advancements,particularly when combined with immune checkpoint *** approaches have shown promise in preclinical and clinical settings,by enhancing patient survival *** review describes the evolving understanding of the c GAS-STING pathway's involvement in tumor biology and ***,this review explores classical and non-classical STING agonists,providing insights into their mechanisms of action and potential for optimizing immunotherapy *** challenges and complexities,the c GAS-STING pathway,a promising avenue for enhancing cancer treatment efficacy,has the potential to revolutionize patient outcomes.

关键词： cGAS-STING pathway type I interferon cyclic dinucleotide STING agonist cancer immunotherapy

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Silvestrol alleviates glioblastoma progression through ERK pathway modulation and MANBA and NRG-1 expression

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BIOcELL 2024年第7期48卷 1081-1093页

作者： lan ZHOU QI ZHANG BO TIAN FENG YANG Neurosurgery Department The First Affiliated Hospital of Chongqing Medical and Pharmaceutical CollegeChongqingChina Neurosurgery Department Changdu People’s Hospital of TibetChangduChina

Background:Glioblastoma,a notably malignant tumor within the central nervous system,is distinguished by its aggressive ***,a robust inhibitor of the RNA helicase eukaryotic initiation factor 4A(eIF4A),has shown significant potential as an anticancer ***,the impact of silvestrol on glioblastoma,especially its molecular mechanisms,has not been fully ***:This investigation employed a variety of in vitro assays,such as cell counting kit-8(ccK-8),clonogenic,5-ethynyl-2′-deoxyuridine(EDU),wound healing,and flow cytometry,to evaluate cell cycle progression,apoptosis,cell viability,and *** blot analysis was also performed to study the apoptosis and extracellular regulated kinase(ERK)*** the ERK pathway was inhibited,differentially expressed genes(DEGs)in U87 cells were identified,followed by an analysis of target genes using the gene expression profiling interactive analysis(GEPIA)***:Silvestrol significantly suppressed the proliferation,migration,and colony formation of glioma *** caused cell cycle arrest and enhanced apoptosis in these ***,silvestrol stimulated the ERK pathway,with these effects being reversible by an ERK phosphorylation *** combined with GEPIA,GScA,UALcAN,TIMER database screened 4 potential drug targets of silvestrol:chromosome 1 open reading frame 226(c1ORF226),mannosidase beta A(MANBA),IQ motif and Sec7 domain 2(IQSEc2),neuregulin 1(NRG-1).Among them,c1ORF226 was lower risk gene while MANBA,IQSEc2,and NRG-1 were high-risk ***,silvestrol notably reduced MANBA mRNA levels,which could be reversed by inhibiting ERK ***,silvestrol markedly decreased NRG-1 protein levels,with an additional reduction observed when the ERK pathway was ***:Silvestrol’s anti-glioma effects are primarily due to the suppression of MANBA expression via the ERK pathway and possibly by hindering the translation of N

关键词： Glioblastoma Silvestrol ERK pathway MANBA NRG-1

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