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Effect of Iron on the Stability of Rhodochrosite at the Topmost Lower Mantle Conditions

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Journal of Earth Science 2024年第2期35卷 504-513页

作者： Tianlei Zhai Fei qin Shengxuan Huang Shan qin Yu gong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing100871China School of Earth Sciences and Resources China University of GeosciencesBeijing100083China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

Carbonates are viewed as the principal oxidized carbon carriers during subduction,and thus the stability of subducted carbonates has significant implications for the deep carbon *** we investigate the high pressure-temperature behaviors of rhodochrosite in the presence of iron up to∼34 GPa by in-situ X-ray diffraction and ex-situ Raman *** relatively low temperature below∼1500 K,MnCO_(3)breaks down into MnO and CO_(2).Upon heating to∼1800 K,however,the MnCO_(3)-Fe^(0)reactions occur with the formation of Mn_(3)O_(4),Fe^(O)and reduced carbon.A'three-stage'reaction mechanism is proposed to understand the kinetics of the carbon-iron-manganese redox *** results suggest that Fe^(0)can serve as a reductant to greatly affect the stability of rhodochrosite,which implies that the effect of Fe-metal should be seriously considered for the high pressure-temperature behaviors of other predominant carbonates at Earth's mantle conditions,particularly at depths greater than∼250 km.

关键词： deep carbon cycle rhodochrosite reduced mantle diamond formation high pressure tectonics geochemistry

Cervical aortic arch with aneurysm formation and an anomalous right subclavian artery and left vertebral artery:A case report

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World Journal of Clinical Cases 2022年第10期10卷 3291-3296页

作者： Yao-Kun Wu Qi Mao Mao-Ting Zhou Ning Liu Xi Yu Jin-Cheng Peng Yun-Yun Tao xue-qin gong Lin Yang Xiao-Ming Zhang Medical Imaging Key Laboratory of Sichuan Province Nanchong 637000Sichuan ProvinceChina Medical Research Center Department of RadiologyThe Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

BACKGROUND A cervical aortic arch(CAA)refers to a high-riding aortic arch(AA)that often extends above the level of the *** condition is very rare,with an incidence of less than 1/*** SUMMARY A 29-year-old woman was admitted to the otolaryngology department of our hospital for repeated bilateral purulent nasal discharge for the prior 3 *** patient was diagnosed with chronic sinusitis and chronic rhinitis at admission.A preoperative noncontrast chest computed tomography scan showed a high-riding,tortuous AA extending to the mid-upper level of the first thoracic vertebra with local cystic dilatation.A further computed tomography angiography examination showed that the brachiocephalic trunk,left common carotid artery,left vertebral artery(LVA)(slender),and left subclavian artery sequentially branched off of the aorta from the proximal end to the distal end of the *** proximal end of the right subclavian artery(RSCA)was tortuous and *** AA showed tumorlike local expansion,with a maximum diameter of approximately 4 *** consultation with the department of cardiac macrovascular surgery,the patient was diagnosed with left CAA with aneurysm formation and an anomalous RSCA and LVA and was transferred to that *** patient underwent AA aneurysm resection and artificial blood vessel replacement under general anesthesia and cardiopulmonary *** abnormality was found during the 2-mo follow-up after *** A CAA is a rare congenital anomaly of vascular *** present unique case of CAA with aneurysm formation and an anomalous RSCA and LVA enriches existing CAA data.

关键词： Cervical aortic arch Aortic aneurysm Aortic anomaly Computed tomography angiography Haughton classification Case report

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： xue-qin Li Lu-Kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research(International) 2024年第2期31卷 329-341页

作者： Jin-sheng Liu Zhen-xing Xing gong-jin Cheng xue-yong Ding Xiang-xin xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure

Intensified warming suppressed the snowmelt in the Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 452-463页

作者： Xiang LI Peng CUI xue-qin ZHANG Fang ZHANG Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China‒Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Understanding how hydrological factors interrelate is crucial when examining the impact of climate warming on ***,these connections are often overlooked,leading to an unclear relationship between temperature and *** study investigates the complex interplay between temperature and snowmelt in the Tibetan Plateau from 1961 to 2020,focusing on how extreme high-temperature events affect the frequency of extreme *** a structural equation model,we detected three temperature-related factors that predominantly influenced snowmelt and extreme *** annual average temperature was found to have a significant indirect impact on snowmelt,mediated by changes in snowfall,snow depth and snow *** contrast,high-temperature days(daily maximum temperatures exceeding the 90th percentile)and heat waves(at least three consecutive high-temperature days)negatively affected extreme snowmelt directly or *** direct effect of increasing extreme temperature events was associated with an earlier onset of high-temperature periods,which accelerated snowmelt and shortened the duration of extreme snowmelt ***,the reduction in snow cover owing to warming emerged as a main factor suppressing snowmelt and extreme snowmelt *** also revealed spatiotemporal variations in the temperature‒snowmelt relationship that highly depended on changes in snowmelt *** study elucidated why warming suppresses snowmelt and extreme snowmelt events in the Tibetan Plateau,highlighting the mediating roles of snow-related and phenological *** findings will provide scientific support for climate simulation and water management policymaking in alpine regions worldwide.

关键词： Climate change Extreme temperature Snowmelt Structural equation model Tibetan Plateau

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： xue-qin Ji Xiao-song Zhang Chen-jun Yang Xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

A Robust N-Terminal Pro-Brain Natriuretic Peptide Assay for Clinical Diagnosis of Heart Failure in Elderly Patients

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Journal of Analysis and Testing 2024年第1期8卷 74-82页

作者： xue gong Jiangling Wu Jiajia Zhang Zhongwei Jiang Yi Wang Pu Zhang Engineering Research Center for Biotechnology of Active Substances(Ministry of Education) Chongqing Key Laboratory of Green Synthesis and ApplicationsCollege of ChemistryChongqing Normal UniversityChongqing 401331China Chongqing Research Center for Pharmaceutical Engineering College of PharmacyChongqing Medical UniversityChongqing 400016China Department of Clinical Laboratory University Town Hospital of Chongqing Medical UniversityChongqing 401331China

Heart failure(HF)is a clinical hallmark of cardiovascular syndrome leading to substantial morbidity,repeated hospitalization,and enormous healthcare *** elderly populations continue to increase,biomarker-guided diagnosis and treatment for age-related cardiac decline have become *** evidence demonstrates that N-terminal proBNP(NT-proBNP)can provide a unique window into the diagnosis and risk stratification with ***,a simple yet robust aptasensor is developed for on-site recognizing the NT-proBNP by its targeting aptamer,thus achieving the accurate diagnosis of *** aptasensing system is prepared by absorbing the fluorophore-labeled aptamer strand onto the graphene oxide(GO),leading to efficient quenching without possible off-site signal *** aptamer strand can specifically identify target NT-proBNP molecules via a versatile conformational transformation,resulting in the desorption of the aptamer-NTproBNP complexes from GO and re-generation fluorescence signal,thus allowing sensitive detection of NT-proBNP in 37 clinical blood *** advantage of the high specificity of aptamer-guaranteed recognitions of NT-proBNP,this aptasensor system readily achieves better diagnostic performance for HF than commercially adopted chemiluminescence immunoassay(Siemens,CLIA)in hospitals in terms of accuracy(89.2%vs 83.8%),specificity(89.5%vs 84.2%),and positive predictive value(88.9%vs 83.3%).This work provides a stable option for the diagnosis and treatment of elderly HF-related diseases inclinics.

关键词： NT-proBNP Graphene oxide Aptamer Heart failure Clinical diagnosis

Digital CEOs in Digital Enterprises:Automating,Augmenting,and Parallel in Metaverse/CPSS/TAOs

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 820-823页

作者： Juanjuan Li Rui qin Sangtian Guan Xiao xue Peng Zhu Fei-Yue Wang with State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China the College of Intelligence and Computing Tianjin UniversityTianjin 300072China School of Economics and Management Nanjing University of Science and TechnologyNanjing 210094China the State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China

BIG models or foundation models are rapidly emerging as a key force in advancing intelligent societies[1]–[3]Their significance stems not only from their exceptional ability to process complex data and simulate advan... 详细信息

关键词： exceptional Auto advancing

The stance and factors of international organizations towards countries from a Chinese perspective

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Data Intelligence 2024年第1期6卷 158-182页

作者： qin Zhang Haili xue Yaotian Wang Yao Wang Ziqin Zhang qinghua qin Haoguang Liang National Science Library Chinese Academy of Sciences100190China China Center for Modernization Research 100190China Beijing International Studies University 100024China Beijing Key Laboratory of National Belt and Road Data Analysis and Decision Support 100024China University College London WC1E 6BTUK

The degree and scope of constraints imposed by International Organizations(IOs)on States are increasing,and identifying the factors affecting the IOs’stances on States is helpful to enhance the state's discourse power and influence in the international ***,by coding the records of Regular Press Conferences of the Speaking Office of the Chinese Ministry of Foreign Affairs during the period of 20182022,we obtained a dataset of IOs’stances on China-related ***,we constructed political relation,economic relation,and humanistic relation indicators to complement the influence factors,adopted the Bayesian logit model,and applied the Monte Carlo Markov chain algorithm and Gibbs sampling to analyze the probability of IOs’positive stances towards *** result shows that IOs’category,length of establishment,functional position,and relationship with China are all related to their tendency of making a statement about *** terms of the heterogeneity of event types,forum-type IOs are significantly inclined to give positive assessment compared to service-type IOs on events focusing on China's own *** analysis reveals that the model for analyzing and predicting the attitudes of IOs is more effective when the international situation is in a stable period.

关键词： Bayesian Logit Model IOs' stances Attitude analysis Monte Carlo Markov chain International relation indicator