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Relations between integrated and monochromatic luminosities of flat-spectrum radio quasars

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Research in Astronomy and Astrophysics 2011年第4期11卷 401-410页

作者： Zhi-Fu Chen Zhao-Yu Chen Yi-Ping Qin Min-Feng Gu Lian-Zhong LU cheng-yue su You-Bing Li Ye Chen Center for Astrophysics Guangzhou University Guangzhou 510006 China epartment of Astronomy Peking University Beijing 100871 China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Physics Department Guangxi University Nanning 530004 China Department of Physics Guangdong University of-Technology Guangzhou 530004 China Guangzhou City Construction College Guangzhou 530004. China

We employ a sample of 362 flat-spectrum radio quasars （FSRQs） to calculate their integrated luminosities by integrating the spectral energy distribution （SED） constructed with multi-band （radio, IR, optical, UV and X-ray） data. We compare these luminosities with those estimated from monochromatic luminosities by multi- plying them by the conventional bolometric correction factors. Our analysis shows that the integrated luminosities calculated from the SED are much larger than the bolometric luminosities estimated from monochromatic luminosities. Their departing behavior tightly correlates with radio luminosities. The relations between integrated and monochromatic luminosities are explored, which are regarded as empirical rela- tions that might be more suitable to be applied to estimate integrated luminosities of FSRQs from their monochromatic luminosities.

关键词： methods statistical -- galaxies active -- galaxies jets

A Time-Domain Numerical Simulation for Free Motion Responses of Two Ships Advancing in Head Waves

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China Ocean Engineering 2024年第3期38卷 519-530页

作者： PAN su-yong cheng Yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The constant panel method within the framework of potential flow theory in the time domain is developed for solving the hydrodynamic interactions between two parallel ships with forward *** solving problems within a time domain framework,the free water surface needs to simultaneously satisfy both the kinematic and dynamic boundary conditions of the free water *** provides conditions for adding artificial damping *** the Runge−Kutta method to solve equations related to *** upwind differential scheme is used in the present method to deal with the convection terms on the free surface to prevent waves *** the comparison with the available experimental data and other numerical methods,the present method is proved to have good mesh convergence,and satisfactory results can be *** constant panel method is applied to calculate the hydrodynamic interaction responses of two parallel ships advancing in head *** simulations are conducted on the effects of forward speed,different longitudinal and lateral distances on the motion response of two modified Wigley ships in head *** further investigations are conducted on the effects of different ship types on the motion response.

关键词： ship motions time domain simulation forward speed different distances wave loads

Free amino group-directed C(sp^(2))-H arylation ofα-amino-β-aryl esters by palladium catalysis

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Chinese Chemical Letters 2024年第2期35卷 358-360页

作者： yue Gao Yu Du Weiping su State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Native amino-directed palladium-catalyzed C(sp^(3))-H activation/functionalization has been developed for modification ofα-amino acids and *** a palladium(Ⅱ)-catalyzed C(sp^(2))-H arylation ofα-amino-β-aryl esters has been disclosed,using the native amino as the directing group.A variety of chiralα-amino-β-aryl esters can be functionalized to give the corresponding ortho-substituted mono-and di-arylated products.

关键词： Native amino-directed Palladium catalyst C(sp^(2))-H arylation α-Amino-β-aryl ester Chiralα-amino acid

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

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Engineering 2024年第7期38卷 144-154页

作者： Jun-su Zhou Long cheng Yuan Gao Zhan-Peng Ge Bin Zhou Jing-Ya Li Jin-Xin Zhao Jian-Min yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Four new norditerpenoid heterodimers with different dimerization patterns-namely,trigofragiloids A-C(denoted as compounds 1-3)and(+)-and(-)-trigofragiloid D(compound 4)-and three new phenanthrenone norditerpenoids-namely,trigofragiloids E-G(compounds 5-7)-were isolated from Trigonostemon *** 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid;they have been identified as class 2 atropisomers by means of quantum chemical *** 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization ***(+)-and(-)-4 are the first example of S-shaped 1,4-dioxane-fused norditerpenoid *** by the structure elucidation of compound 4,two co-occurring analogues,actephilol A and epiactephilol A,were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers,(+)-and(-)-8 and(+)-and(-)-9,*** structures were characterized using a combined ***,compound 7 exhibits remarkable adenosine triphosphate-citrate lyase(ACLY)inhibition with a halfmaximal inhibition concentration(IC50)value of(0.46±0.11)lmol·L^(-1),as active as the positive control BMS-303141,and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer Trigonostemon fragilis Euphorbiaceae Trigofragiloid Structural revision Adenosine triphosphate-citrate lyase(ACLY) inhibitory activity

Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China

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Chinese Geographical Science 2024年第1期34卷 135-148页

作者： WANG Zili LU Chunyan su Yanlin su yue YU Qianru LI Wenzhe YANG Nuocheng College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou350002China Key Laboratory of Smart Agriculture and Forestry(Fujian Agriculture and Forestry University) Fujian Province UniversityFuzhou350002China College of Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China

Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly *** order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving *** the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to *** comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically *** results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the *** was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space *** LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated *** and water bodies had a significant mitigation effect on UHI,especially in the *** winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading *** research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.

关键词： winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City,China

Molecular Dynamics Simulation Studies on the Micromorphology and Proton Transport of Nafion/Ti_(3)C_(2)T_(x) Composite Membrane

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Chinese Journal of Polymer Science 2024年第3期42卷 373-387,I0009页

作者： Zhi-yue Han su-Peng Pei Chun-Yang Yu Yong-Feng Zhou School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China School of Chemistry&Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Green and High-end Utilization of Salt Lake Resources Chinese Academy of SciencesXining 810008China

The perfluorosulfonic acid(PFSA) membrane doped with two-dimensional conductive filler Ti_(3)C_(2)T_(x) is a fuel cell proton exchange membrane with high application potential. Experimental studies showed that the proton conductivity of Nafion/Ti_(3)C_(2)T_(x) composite membrane is improved significantly compared with that in pure Nafion. However, the microscopic mechanism of doping on the enhancement of membrane performance is remain unclear now. In this work, molecular dynamics simulation was used to investigate the microscopic morphology and proton transport behaviors of Nafion/Ti_(3)C_(2)T_(x) composite membrane at the molecular level. The results shown that there were significant differences about the diffusion kinetics of water molecules and hydroxium ions in Nafion/Ti_(3)C_(2)T_(x) at low and high hydration levels in the nanoscale *** the increase of water content, Ti_(3)C_(2)T_(x) in membrane was gradually surrounded by ambient water molecules to form a hydration layer, and forming a relatively continuous proton transport channel between Nafion polymer and Ti_(3)C_(2)T_(x) monomer. The continuous proton transport channel could increase the number of binding sites of proton and thus achieving high proton conductivity and high mobility of water molecules at higher hydration level. The current work can provide a theoretical guidance for designing new type of Nafion composite membranes.

关键词： Nafion/Ti_(3)C_(2)T_(x)composite membrane Proton transport Molecular dynamics simulation

Low-Rank Optimal Transport for Robust Domain Adaptation

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1667-1680页

作者： Bingrong Xu Jianhua Yin cheng Lian Yixin su Zhigang Zeng IEEE the School of Automation Wuhan University of TechnologyWuhan 430070China Intelligent Transportation Systems Research Center Wuhan University of TechnologyWuhan 430063 Chongqing Research Institute Wuhan University of TechnologyChongqingChina the School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074 the Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China Wuhan 430074China

When encountering the distribution shift between the source(training) and target(test) domains, domain adaptation attempts to adjust the classifiers to be capable of dealing with different domains. Previous domain adaptation research has achieved a lot of success both in theory and practice under the assumption that all the examples in the source domain are welllabeled and of high quality. However, the methods consistently lose robustness in noisy settings where data from the source domain have corrupted labels or features which is common in reality. Therefore, robust domain adaptation has been introduced to deal with such problems. In this paper, we attempt to solve two interrelated problems with robust domain adaptation:distribution shift across domains and sample noises of the source domain. To disentangle these challenges, an optimal transport approach with low-rank constraints is applied to guide the domain adaptation model training process to avoid noisy information influence. For the domain shift problem, the optimal transport mechanism can learn the joint data representations between the source and target domains using a measurement of discrepancy and preserve the discriminative information. The rank constraint on the transport matrix can help recover the corrupted subspace structures and eliminate the noise to some extent when dealing with corrupted source data. The solution to this relaxed and regularized optimal transport framework is a convex optimization problem that can be solved using the Augmented Lagrange Multiplier method, whose convergence can be mathematically proved. The effectiveness of the proposed method is evaluated through extensive experiments on both synthetic and real-world datasets.

关键词： Domain adaptation low-rank constraint noise corruption optimal transport

Effect of Y and Ce Micro-alloying on Microstructure and Hot Tearing of As-Cast Al-Cu-Mg Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 939-952页

作者： Chunyu yue Bowen Zheng Ming su Yuxiang Wang Xiaojiao Zuo Yinxiao Wang Xiaoguang Yuan School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China Institute of Metal Research Chinese Academy of SciencesShenyang110016China

In this work,the Al-Cu-Mg alloy with different Y(0-0.2 wt%)and Ce(0.5-1.5 wt%)are *** effect of mixed addition of Y and Ce on the grain structure and hot tearing for Al-4.4Cu-1.5Mg-0.15Zr alloy was investigated using"cross"hot tearing *** results indicate that as rare earth Y and Ce increases,the grain size becomes finer,the grain morphology changes from dendrite to equiaxed grain,and effectively reduce the hot tearing sensitivity coefficient(HTS1)and crack susceptibility coefficient(CSC)of the *** the increase of Ce element(0.5-1.5 wt%),the hot tearing susceptibility of the alloy decreases first and then *** the increase of Y element(0-0.2 wt%),the hot tearing sensitivity of the alloy *** the content of rare earth is 0.2 wt%Y+1.0 wt%Ce,the minimum HTS1 value and CSC value of the alloy are 68 and 0.53,*** earth Ce refines the alloy microstructure,shortens the feeding channel,and reduces the hot tearing ***,the rare earth Y can form Al6Cu6Y phase at the grain boundary,improve the feeding capacity of the ***,appropriate addition of rare earth Y and Ce can effectively reduce the hot tearing tendency of the alloy.

关键词： Al-Cu-Mg alloy Y and Ce Microstructure Thermal analysis Hot tearing sensitivity

Multiple conductive network for KTi_(2)(PO_(4))_(3)anode based on MXene as a binder for high-performance potassium storage

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Chinese Chemical Letters 2024年第8期35卷 539-544页

作者： Tong su yue Wang Qizhen Zhu Mengyao Xu Ning Qiao Bin Xu State Key Laboratory of Organic-Inorganic Composites Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China

KTi_(2)(PO_(4))_(3)is a promising anode material for potassium storage,but suffers from low conductivity and difficult balance between high capacity and good structural ***,the Ti_(3)C_(2)T_(x)MXene is used as a multifunctional binder to fabricate the KTi_(2)(PO_(4))_(3)electrode by the traditional homogenizing-coating *** MXene nanosheets,together with the conductive agent super P nanoparticles,construct a multiple conductive network for fast electron/ion transfer and high electrochemical ***,the network ensures the structural stability of the KTi_(2)(PO_(4))_(3)electrode during the de-intercalation/intercalation of 4 K^(+)ions,which is beneficial for simultaneously achieving high capacity and good cycle ***,the MXene-bonded KTi_(2)(PO_(4))_(3)electrode delivers a reversible capacity of 255.2 mAh/g at 50 mA/g,outstanding rate capability with 132.3 mAh/g at 2 A/g,and ex-cellent cycle performance with 151.6 mAh/g at 1 A/g after 2000 *** work not only suggests a high-performance anode material for potassium-ion batteries,but also demonstrates that the MXene is a promising binder material for constructing conductive electrodes in rechargeable batteries.

关键词： MXene Ti_(3)C_(2)T_(x) KTi_(2)(PO_(4))_(3) Anode Conductive network Potassium storage