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Quantitative Analysis of Seeing with Height and Time at Muztagh-Ata Site Based on ERA5 Database

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Research in Astronomy and Astrophysics 2024年第1期24卷 87-95页

作者： xiao-Qi Wu Cun-Ying xiao Ali Esamdin Jing Xu Ze-Wei wang Luo xiao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Seeing is an important index to evaluate the quality of an astronomical *** estimate seeing at the Muztagh-Ata site with height and time quantitatively,the European Centre for Medium-Range Weather Forecasts reanalysis database(ERA5)is *** calculated from ERA5 is compared consistently with the Differential Image Motion Monitor seeing at the height of 12 *** show that seeing decays exponentially with height at the Muztagh-Ata *** decays the fastest in fall in 2021 and most slowly with height in *** seeing condition is better in fall than in *** median value of seeing at 12 m is 0.89 arcsec,the maximum value is1.21 arcsec in August and the minimum is 0.66 arcsec in *** median value of seeing at 12 m is 0.72arcsec in the nighttime and 1.08 arcsec in the *** is a combination of annual and about biannual variations with the same phase as temperature and wind speed indicating that seeing variation with time is influenced by temperature and wind *** Richardson number Ri is used to analyze the atmospheric stability and the variations of seeing are consistent with Ri between *** quantitative results can provide an important reference for a telescopic observation strategy.

关键词： site testing atmospheric effects methods:data analysis telescopes Earth

Forecast of cosmological constraints with superluminous supernovae from the Chinese Space Station Telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 128-138页

作者： xuan-Dong Jia Jian-Ping Hu Fa-Yin wang Zi-Gao Dai School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Superluminous supernovae(SLSNe)are a class of intense celestial events that can be standardized for measuring cosmological parameters,bridging the gap between type Ia supernovae and the cosmic microwave *** this work,we discuss the cosmological applications of SLSNe from the Chinese Space Station Telescope(CSST).Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate,exhibiting a factor of(1+z)^(1.2).We futher predict that CSST is poised to observe~360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years.A stringent constraint on cosmological parameters can be derived from their peak-color *** is anticipated to uncover a substantial number of SLSNe,contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

关键词： supernovae cosmology cosmological constant

Improved direct current electrical properties of XLPE modified by graftable antioxidant and crosslinking coagent at a wide temperature range

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High Voltage 2024年第1期9卷 94-104页

作者： Xu Yang Hong Zhao Chengcheng Zhang Chunyang Li Xindong Zhao Jiaming Yang xuan wang Key Laboratory of Engineering Dielectrics and Its Application Harbin University of Science and TechnologyHarbinChina

To enhance the DC electrical performance of cross-linked polyethylene(XLPE),the graftable antioxidant methacrylic acid 2-hydroxy-3-(4-anilinoanilino)propyl ester(GA),which contains carbonyl and amino groups,and the crosslinking coagent trimethylolpropane trimethacrylate(TMPTMA),which contains carbonyl groups,are individually or co-grafted onto *** slightly higher deep trap density introduced by higher grafting concentration of TMPTMA results in more significant suppression effect of conductance current and enhanced breakdown strength at a lower temperature,while the suppression effect for the conductance current at 90°C becomes weakened due to limited trap ***,the deeper energy level introduced by GA suppresses the conductance current and improves the electrical strength of XLPE at 90°C more *** co-grafting,the conductance current of XLPE in a wide range temperature can be significantly reduced,especially for the temperature dependence of conductance current,which is beneficial to suppress the field strength *** results of thermally stimulated current and molecular simulation show that the polar groups of two monomers introduce deep charge traps in *** co-grafting system ensures the rationality of the crosslinking reaction kinetics and does not affect the cable manufacturing.

关键词： crosslinking electrical grafting

CPL-active hybrid copper(Ⅰ)halides enabled by cation inclusion with chiral crown-ether

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Science China Chemistry 2024年第10期67卷 3283-3290页

作者： Peng Fan Li-xuan Cai xiao-Fang Duan Fan Yin Chen-Chen Li Zhong-Hua Deng xiao-Zhen Li Qing-Fu Sun College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Strait Institute of Flexible Electronics(Future Technologies) Fujian Key Laboratory of Flexible ElectronicsFujian Normal University and Strait Laboratory of Flexible ElectronicsFuzhou 350117China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian College University of Chinese Academy of SciencesFuzhou 350002China

Chiral hybrid metal halides with high photoluminescence quantum yield(PLQY)and superior dissymmetry factor(g_(lum))are promising candidates for circularly polarized luminescence(CPL)emitting ***,it is a great challenge to achieve both high g_(lum)and large ***,we report a new supramolecular strategy to fabricate chiral hybrid Cu(Ⅰ)-halides with nearunity quantum yields and intense CPL *** dissymmetry factor can be dramatically modulated by tuning the hostguest *** to the chirality and variable conformations of the host-guest complexes,a series of chiral[G@L^(R/S)]_(2)Cu_(4)I_(6)have been *** incorporation of different cations within the chiral L^(R/S)hosts leads to variations of packing modes along the c-axis and different extent of distortions in the[Cu_(4)I_(6)]_(2)-*** them,[H_(3)O@L^(R/S)]+cations are stacked based on Van der Waals interactions and hierarchically self-assemble into a right/left-handed helix in[H_(3)O@L^(R/S)]_(2)Cu_(4)I_(6),which results in a high g_(lum)of-7×10^(-3)and a large PLQY of 96.92%.Notably,[G@L^(R/S)]_(2)Cu_(4)I_(6)shows promising applications in single-component white light emitting diodes(WLEDs),exhibiting a maximum dissymmetry factor of-1.2×10^(-3).The effective host-guest complexation and oriented hierarchical self-assembly provide an effective strategy for the development of high-performance CPL materials.

关键词： host-guest interaction circularly polarized luminescence copper iodide cluster hierarchical self-assembly chirality

Magnetic resonance imaging-based lymph node radiomics for predicting the metastasis of evaluable lymph nodes in rectal cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1849-1860页

作者： Yong-Xia Ye Liu Yang Zheng Kang Mei-Qin wang xiao-Dong Xie Ke-Xin Lou Jun Bao Mei Du Zhe-xuan Li Department of Radiology The Affiliated Cancer Hospital of Nanjing Medical University&Jiangsu Cancer Hospital&Jiangsu Institute of Cancer ResearchNanjing 210011Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and The Affiliated Cancer Hospital of Nanjing Medical UniversityNanjing 210000Jiangsu ProvinceChina1 Department of Pathology The Affiliated Cancer Hospital of Nanjing Medical University&Jiangsu Cancer Hospital&Jiangsu Institute of Cancer ResearchNanjing 210011Jiangsu ProvinceChina Colorectal Center The Affiliated Cancer Hospital of Nanjing Medical University&Jiangsu Cancer Hospital&Jiangsu Institute of Cancer ResearchNanjing 210011Jiangsu ProvinceChina

BACKGROUND Lymph node(LN)staging in rectal cancer(RC)affects treatment decisions and patient *** radiologists,the traditional preoperative assessment of LN metastasis(LNM)using magnetic resonance imaging(MRI)poses a *** To explore the value of a nomogram model that combines Conventional MRI and radiomics features from the LNs of RC in assessing the preoperative metastasis of evaluable *** In this retrospective study,270 LNs(158 nonmetastatic,112 metastatic)were randomly split into training(n=189)and validation sets(n=81).LNs were classified based on pathology-MRI *** MRI features[size,shape,margin,T2-weighted imaging(T2WI)appearance,and CE-T1-weighted imaging(T1WI)enhancement]were *** radiomics models used 3D features from T1WI and T2WI ***,a nomogram model combining conventional MRI and radiomics features was *** model used univariate analysis and multivariable logistic *** employed the receiver operating characteristic curve,with DeLong test for comparing diagnostic *** performance was assessed using calibration and decision curve *** The nomogram model outperformed conventional MRI and single radiomics models in evaluating *** the training set,the nomogram model achieved an area under the curve(AUC)of 0.92,which was significantly higher than the AUCs of 0.82(P<0.001)and 0.89(P<0.001)of the conventional MRI and radiomics models,*** the validation set,the nomogram model achieved an AUC of 0.91,significantly surpassing 0.80(P<0.001)and 0.86(P<0.001),*** The nomogram model showed the best performance in predicting metastasis of evaluable LNs.

关键词： Radiomics Lymph node metastasis Rectal cancer Magnetic resonance imaging

shinyTempSignal:an R shiny application for exploring temporal and other phylogenetic signals

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Journal of Genetics and Genomics 2024年第7期51卷 762-768页

作者： Li Zhan xiao Luo Wenqin Xie xuan-An Zhu Zijing Xie Jianfeng Lin Lin Li Wenli Tang Rui wang Lin Deng Yufan Liao Bingdong Liu Yantong Cai Qianwen wang Shuangbin Xu Guangchuang Yu Department of Bioinformatics School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China Faculty of Computers Guangdong University of TechnologyGuangzhouGuangdong 510006China Ubigene Biosciences Co. Ltd.GuangzhouGuangdong 510530China State Key Laboratory of Applied Microbiology Southern China Guangdong Provincial Key Laboratory of Microbial Culture Collection and ApplicationGuangdong Open Laboratory of Applied MicrobiologyGuangdong Institute of MicrobiologyGuangdong Academy of SciencesGuangzhouGuangdong 510070China

The molecular clock model is fundamental for inferring species divergence times from molecular ***,its direct application may introduce significant biases due to sequencing errors,recombination events,and inaccurately labeled sampling *** accuracy necessitates rigorous quality control measures to identify and remove potentially erroneous ***,while not all branches of a phylogenetic tree may exhibit a clear temporal signal,specific branches may still adhere to the assumptions,with varying evolutionary *** a relaxed molecular clock model better aligns with the complexities of *** root-to-tip regression method has been widely used to analyze the temporal signal in phylogenetic studies and can be generalized for detecting other phylogenetic *** its utility,there remains a lack of corresponding software implementations for broader *** address this gap,we present shinyTempSignal,an interactive web application implemented with the shiny framework,available as an R package and publicly accessible at https://***/YuLab-SMU/*** tool facilitates the analysis of temporal and other phylogenetic signals under both strict and relaxed *** extending the root-to-tip regression method to diverse signals,shinyTempSignal helps in the detection of evolving features or traits,thereby laying the foundation for deeper insights and subsequent analyses.

关键词： Molecular clock Root-to-tip regression Temporal signal Phylogenetic signal

Optimizing hybrid electric vehicle coupling organic Rankine cycle energy management strategy via deep reinforcement learning

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Energy and AI

Energy and AI 2024年第3期17卷 295-312页

作者： xuanang Zhang xuan wang Ping Yuan Hua Tian Gequn Shu State Key Laboratory of Engines Tianjin UniversityNo.92Weijin RoadNankai DistrictTianjin300072China Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei230027China

Trucks consume a lot of energy. Hybrid technology maintains a long range while realizing energy savings. Hybrid is therefore an effective energy-saving technology for trucks. Recovery of engine waste heat through the organic Rankine cycle further enhances engine efficiency and provides effective thermal management. However, the powertrain greatly increases the complexity of energy management system. In order to design an energy management system with high efficiency and robustness, this study proposes a deep reinforcement learning embedded rule-based energy management system. This method optimises the key parameters of the rule-based energy management system by inserting deep reinforcement learning into it. Therefore, this scheme combines the good optimization effect of deep reinforcement learning and the excellent robustness of rule. In order to verify the feasibility of this scheme, this study builds the system dynamic model and carries out a simulation study. Subsequently, a hybrid powertrain semi physical experimental bench was constructed and a rapid control prototype experimental study was carried out. The simulation results show that the deep reinforcement learning embedded rule-based energy management system can reduce the energy consumption by 4.31 % compared with the rule-based energy management system under the C-WTVC driving cycle. In addition, energy saving and safe operation can also be achieved under other unfamiliar untrained driving cycles. The rapid control prototype experimental study shows that the deep reinforcement learning embedded rule-based energy management system has good agreement in experiment and simulation, which demonstrates the potential for real vehicle engineering applications and promotes the engineering application of deep reinforcement learning.

关键词： Deep reinforcement learning Hybrid electric vehicle Organic Rankine cycle Energy management system Rapid control prototype

Paleoenvironmental reconstruction and organic matter accumulation of the paleogene shahejie oil shale in the Zhanhua Sag, Bohai Bay Basin, Eastern China

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Petroleum Science 2024年第3期21卷 1552-1568页

作者： xiao-Lin wang xiao-Min Zhu Jin Lai Xing-Yue Lin Xiang wang Yu-Shan Du Chao Huang Yu-Rui Zhu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Shengli Oilfield SINOPECDongying257000ShandongChina

The controlling factors of organic-rich shale accumulation is essential for the exploration and development of shale oil and gas *** sedimentary environment plays a vital role in the formation of organic-rich sediments in lacustrine *** article unravels the mineralogy,geochemistry,and paleoenvironmental evolution during the deposition of the Paleogene Shahejie Formation(Es_(3)^(L)).It discusses the effects of paleoclimate,paleosalinity,paleoredox conditions,paleowater depth,and paleoproductivity on organic matter(OM)***,the OM enrichment model was *** results show that the mineralogical compositions are mainly composed of calcite(avg.40.13%),quartz(avg.21.64%)and clay minerals(avg.24.07%),accompanied by dolomite(avg.7.07%),feldspar(avg.6.36%)and pyrite(avg.2.95%).The Es_(3)^(L) shale has a high abundance of OM,with total organic carbon(TOC)ranging from 1.07%to 5.12%.The organic matter type is mainly composed of type I-II_(1) kerogen,which is generally considered a good-quality source *** source of OM is a mixture of lower bacteria,algae,and *** the early sedimentary period,the paleoclimate was dry and cold,with high salinity,intense reducibility,and relatively low *** the late sedimentary period,the climate became warmer and more *** a result,the salinity decreased to a level that was suitable for biological reproduction,and productivity increased gradually due to the input of terrigenous *** and paleoclimate determined the environment of the sedimentary period,in addition,paleoproductivity and paleoredox condition indicated the formation and preservation conditions of *** warm and humid climate,brackish water,suitable reduction conditions and high productivity are the favorable conditions for the generation and preservation of organic *** research results may have implications for the genetic mechanisms of organic matter *** will provide theoret

关键词： Elemental geochemical Paleoenvironment Organic matter accumulation Paleogene shahejie formation Zhanhua Sag Bohai Bay Basin

Experimental Study on Engineering Behavior of Solidified Soil for Scour Repair and Protection

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China Ocean Engineering 2024年第4期38卷 625-635页

作者： WU xiao-ni LI Ru-yu SHU Jian TANG Chao CHEN Jin-jian wang Hui-li JIANG Hai-li wang xiao State Key Laboratory of Ocean Engineering Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Road and Bridge Group Co. Ltd.Shanghai 200433China Shanghai Engineering Research Center of Urban Infrastructure Renewal Shanghai 200032China Jiangsu Kunze Technology Co. Ltd.Nanjing 210000China

A new scour countermeasure using solidified slurry for offshore foundation has been proposed *** solidified slurry is pumped to seabed area around foundation for scour protection or pumped into the developed scour holes for scour repair as the fluidized material solidifies *** the pumping operation and solidification,the engineering behaviors of solidified slurry require to be considered synthetically for the reliable application in scour repair and protection of ocean engineering such as the pumpability related flow value,flow diffusion behavior related rheological property,anti-scour performance related retention rate in solidification and bearing capacity related strength property after *** this study,a series of laboratory tests are conducted to investigate the effects of mix proportion(initial water content and binder content)on the flow value,rheological properties,density,retention rate of solidified slurry and unconfined compressive strength(UCS).The results reveal that the flow value increases with the water content and decreases with the binder *** the solidified slurry exhibits Bingham plastic behavior when the shear rate is larger than 5 s^(-1).The Bingham model has been employed to fit the rheology test results,and empirical formulas for obtaining the density,yield stress and viscosity are established,providing scientific support for the numerical assessment of flow and diffusion of solidified *** rate of solidified slurry decreases with the water flow velocity and flow value,which means the pumpability of solidified slurry is contrary to anti-scour *** unconfined compressive strength after solidification reduces as the water content increases and binder content decreases.A design and application procedure of solidified soil for scour repair and protection is also proposed for engineering reference.

关键词： scour repair and protection solidified soil pumpability strength flow properties anti-scour performance