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Spectral Fittings of Warm Coronal Radiation with High Seed Photon Temperature:Apparent Low-temperature and Flat Soft Excess in AGNs

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Research in Astronomy and Astrophysics 2024年第7期24卷 135-144页

作者： Ze-Yuan Tang jun-jie Feng jun-Hui Fan School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China

A warm corona has been widely proposed to explain the soft excess(SE)in X-ray above the 2-10 ke V power law extrapolation in Active Galactic Nuclei(AGNs).In actual spectral fittings,the warm coronal seed photon temperature(T_s)is usually assumed to be far away from the soft X-ray,but kT_scan reach close to 0.1 ke V in the standard accretion disk *** this study,we used Monte Carlo simulations to obtain radiation spectra from a slab-like warm corona and fitted the spectra using the spherical-geometry-based routine THCOMP or a thermal *** findings reveal tha high T_scan influence the fitting results.A moderately high kT_s(around 0.03 ke V)can result in an apparent low-temperature and flat SE,while an extremely high kT_s(around 0.07 ke V)can even produce an unobserved blackbody-like *** conclusions indicate that,for spectral fittings of the warm coronal radiation(SE in AGNs),kT_sshould be treated as a free parameter with an upper limit,and an accurate coronal geometry is necessary when kT_s>0.01 ke V.

关键词： galaxies active-accretion-accretion disks-black hole physics

The occurrence characteristics of oil in shales matrix from organic geochemical screening data and pore structure properties:An experimental study Author links open overlay panel

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Petroleum Science 2024年第1期21卷 1-13页

作者： Zi-Zhi Lin jun-Qian Li Shuang-Fang Lu Qin-Hong Hu Peng-Fei Zhang jun-jie Wang Qi Zhi Hong-Sheng Huang Na yin Yue Wang Tian-Chen Ge National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572025HainanChina College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina

The occurrence characteristics of shale oil are of great significance to the movability of shale *** this study,the occurrence characteristics of oil in the shale matrix at Funing Formation shale in Subei Basin were quantitatively evaluated by organic geochemistry and microscopic pore structure characterization *** Multiple Isothermal Stages Pyrolysis(MIS)experiment results show that the content of total oil,adsorbed oil,and free oil in the shales are 3.15-11.25 mg/g,1.41-4.95 mg/g,and 1.74-6.51 mg/g,*** which the silicon-rich shale has the best *** relative content of free oil shows an increasing trend in pores with pore diameters greater than 3 *** the relative content of free oil reaches 100%,the pore size of silicon-rich shale is about 200 nm,while that of calcium-rich shale,clay-rich shale,and siliceous mixed shale is about 10 *** occurrence law of adsorbed oil is opposite to that of free oil,which indicates that shale oil will occur in the pores and fractures in a free state in a more extensive pore size range(>200 nm).This study also enables us to further understand the occurrence characteristics of shale oil under the interaction of occurrence state and occurrence space.

关键词： Shale oil Occurrence characteristics Sequential solvent extraction Low-temperature nitrogen adsorption Funing Formation Dongtai Depression

Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： jie-Li Wang Wen-jun Huang De-Li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： Deep well Casing integrity Casing wear Casing corrosion Burst strength

Identification and validation of a new prognostic signature based on cancer-associated fibroblast-driven genes in breast cancer

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World Journal of Clinical Cases 2024年第4期12卷 700-720页

作者： Zi-Zheng Wu Yuan-jun Wei Tong Li jie Zheng yin-Feng Liu Meng Han Diagnosis and Treatment Center The First Hospital of QinhuangdaoQinhuangdao 066000Hebei ProvinceChina Department of General Surgery Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Breast Disease Diagnosis and Treatment Center The First Hospital of QinhuangdaoHebei Medical UniversityQinhuangdao 066000Hebei ProvinceChina Breast Disease Diagnosis and Treatment Center Chengde Medical CollegeChengde 067000Hebei ProvinceChina

BACKGROUND Breast cancer(BC),a leading malignant disease,affects women all over the *** associated fibroblasts(CAFs)stimulate epithelial-mesenchymal transition,and induce chemoresistance and *** To establish a CAFs-associated prognostic signature to improve BC patient out-come *** We retrieved the transcript profile and clinical data of 1072 BC samples from The Cancer Genome Atlas(TCGA)databases,and 3661 BC samples from the The Gene Expression *** and immune cell infiltrations were quantified using CIBERSORT ***-associated gene identification was done by weighted gene co-expression network analysis.A CAF risk signature was established via univariate,least absolute shrinkage and selection operator regression,and mul-tivariate Cox regression *** receiver operating characteristic(ROC)and Kaplan-Meier curves were employed to evaluate the predictability of the ***,a nomogram was developed with the risk score and patient clinical *** Spearman's correlations analysis,the relationship between CAF risk score and gene set enrichment scores were *** samples were collected to validate gene expression by quantitative real-time polymerase chain reaction(qRT-PCR).RESULTS Employing an 8-gene(IL18,MYD88,GLIPR1,TNN,BHLHE41,DNAJB5,FKBP14,and XG)signature,we attemp-ted to estimate BC patient *** on our analysis,high-risk patients exhibited worse outcomes than low-risk *** analysis revealed the risk score as an independent indicator of BC patient *** analysis exhibited satisfactory nomogram *** area under the curve showed 0.805 at 3 years,and 0.801 at 5 years in the TCGA *** also demonstrated that a reduced CAF risk score was strongly associated with enhanced chemotherapeutic *** risk score was significantly correlated with most hallmark gene ***,the prognostic signature were further validated by qRT-

关键词： Breast cancer Prognosis Gene signature The Cancer Genome Atlas The Gene Expression Omnibus

New insights into the deposition of natural gas hydrate on pipeline surfaces:A molecular dynamics simulation study

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Petroleum Science 2024年第1期21卷 694-704页

作者： jun Zhang Hai-Qiang Fu Mu-Zhi Guo Zhao Wang Li-Wen Li Qi yin You-Guo Yan Wei Wei Wei-Feng Han jie Zhong School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina Department of Alternative Energy PetroChina Research Institute of Petroleum Exploration&DevelopmentLangfang 065007HebeiChina

Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low *** hydrate adhesion on pipelines is viewed as an efficient way to prevent NGH *** studies suggested the water film can greatly increase hydrate adhesion in gas-dominant ***,by performing the molecular dynamics simulations,we find in water-dominant system,the water film plays different roles in hydrate deposition on Fe and its corrosion ***,due to the strong affinity of water on Fe surface,the deposited hydrate cannot convert the adsorbed water into hydrate,thus,a water film *** water affinities decrease(Fe>Fe_(2)O_(3)>FeO>Fe_(3)O_(4)),adsorbed water would convert to amorphous hydrate on Fe_(2)O_(3)and form the ordered hydrate on FeO and Fe_(3)O_(4)after hydrate *** absorbed water film converts to amorphous or to hydrate,the adhesion strength of hydrate continuously increases(Fe

关键词： Deposition Natural gas hydrate Pipelines Water affinity Adhesion strength

An approach for determination of lateral limit angle in kinematic planar sliding analysis for rock slopes

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1305-1314页

作者： Xiaojuan Yang jie Hu Honglei Sun jun Zheng College of Civil Engineering Zhejiang University of TechnologyHangzhou310023China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Center for Balance Architecture Zhejiang UniversityHangzhou310007China The Architectural Design & Research Institute of Zhejiang University Co. Ltd.Hangzhou310063China

Planar sliding is one of the frequently observed types of failure in rock *** analysis is a classic and widely used method to examine the potential failure modes in rock *** accuracy of planar sliding kinematic analysis is significantly influenced by the value assigned to the lateral limit angleγ***,the assignment ofγlim is currently used generally based on an empirical *** study aims to propose an approach for determining the value ofγlim in deterministic and probabilistic kinematic planar sliding analysis.A new perspective is presented to reveal thatγlim essentially influences the probability of forming a potential planar sliding *** procedure to calculate this probability is introduced using the block theory *** is found that the probability is correlated with the number of discontinuity sets presented in rock ***,different values ofγlim for rock masses with different sets of discontinuities are recommended in both probabilistic and deterministic planar sliding kinematic analyses;whereas a fixed value ofγlim is commonly assigned to different types of rock masses in traditional ***,an engineering case was used to compare the proposed and traditional kinematic analysis *** error rates of the traditional method vary from 45%to 119%,while that of the proposed method ranges between 1%and 17%.Therefore,it is likely that the proposed method is superior to the traditional one.

关键词： Kinematic analysis Block theory Planar sliding Lateral limit angle Rock slope

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu jun-Xiu Shi Yi-Ming Ou Hua-jie Jiang Yi-jun Fang Qi-Ming Wang Quan Gao jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

Four-birds-with-one-stone:A multifunctional Ti-based material for solar-driven water evaporation

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Nano Research 2024年第5期17卷 4498-4506页

作者： Yannan Li Yaning Sun Dan Zhang Yu Xue jie Wang Nan Zhang jun Wang Jiangwei Zhang Yan Zhao jun-jie Liu School of Physical Science and Technology College of Energy Materials and ChemistryInner Mongolia UniversityHohhot 010021China

Sustainable,environmentally friendly and low-energy desalination materials have important research value for the increasing demand of freshwater year by ***,it is a huge challenge to maintain high heat energy transfer efficiency without reducing the heat conversion capacity of specific solar photothermal conversion ***,their efficiency and durability are greatly limited by the problems of seawater corrosion,oil,and bacteria *** now,no related work has been reported to solve all the aforementioned problems via a simple four-birds-with-one-stone ***,a class of multifunctional porous photothermal silver(Ag)modified Ti foams(Tf-TA/Ag series materials)is prepared for the development of advanced solar water evaporation devices,and provides alternative materials for alleviating freshwater crisis and treating *** oil contact angle(OCA)changes from 41°to 180°,which significantly reduces the adhesion of *** addition,Tf-TA2/Ag sample also shows an excellent and sustained antibacterial effect,which maintains above 99.9%of antibacterial rate after repeated 5 *** surface temperature of the Tf-TA2/Ag sample reaches 52.5℃ after simulated sun irradiation for 20 min,which is significantly higher than that of the contact groups(water:36.4℃,Ti foam:38.2℃ and Tf-TA2:40.9℃).The capacity of seawater evaporation and salt removal is enhanced due to the excellent photothermal properties,low reflectance,and uniform heat dissipation *** water production efficiency of Tf-TA2/Ag sample is 1.41 kg·m^(-2)·h^(-1) in artificial seawater and 0.76 kg·m^(-2)·h^(-1) in oily sewage under simulated sun ***,the hydrophilic and oleophobic properties of Tf-TA2/Ag are critical to extracting water from oil/water mixture in diverse water ***,this four-birds-with-one-stone approach provides a new perspective for the improvement of solar seawater desalination performance.

关键词： four-birds-with-one-stone photothermal material antibacterial material antifouling property

Possible Habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in the Initial Conditions of High-mass Star Formation

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

作者： Quan-Ling Cui Chuan-Peng Zhang jun-jie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(H_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the N-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for NH_(3),NH_(2)D,H^(13)CN,HC^(15)N,SO,and C^(18)O in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97S,G25.38,and *** found that the NH3cores are in good agreement with the 3.5 mm peak emission,but the NH_(3)is much more extended than the 3.5 mm emission *** SO distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any SO emission in the four earliest star formation sources.C^(18)O is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the NH_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the NH_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational