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Reaction behavior of MgO refractory with high-Mn and high-Al steel

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1389-1398页

作者： ling-zhong Kong Lin zu Jie Yang Xi-min Zang Xin Yang Ming Kang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

To understand the mechanism of the interfacial reaction between high-Mn and high-Al steel and MgO refractory,a series of laboratory experiments as well as thermodynamic calculations were *** effects of Mn and Al contents in the steel and the reaction time on the interfacial reaction were *** was observed that the erosion of the MgO refractory is caused by the reaction of Al and Mn in the steel with MgO in the refractory,which would lead to the formation of(Mn,Mg)O·Al_(2)O_(3) spinel and(Mn,Mg)O solid *** formation mechanism of the spinel and solid solution is as *** Al in the steel firstly reacts with MgO in the refractory to generate MgO·Al_(2)O_(3) spinel,and then,the spinel reacts with Mn in the steel to form(Mn,Mg)O·Al_(2)O_(3) ***,the MnO in the spinel reacts with the MgO in the inner refractory to form(Mn,Mg)O solid *** addition,only(Mn,Mg)O·Al_(2)O_(3) spinel is present in the interfacial reaction layer of the refractory when the Al content in the steel is sufficient.

关键词： High-Mn high-Al steel MgO refractory Reaction behavior Spinel

Comparison of intraosseous access and central venous catheterization in Chinese adult emergency patients: A prospective, multicenter, and randomized study

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World Journal of Emergency Medicine 2021年第2期12卷 105-110页

作者： Yan-yan Liu Yu-peng Wang ling-yun zu Kang Zheng Qing-bian Ma Ya-an Zheng Wei Gao Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalNHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesKey Laboratory of Molecular Cardiovascular SciencesMinistry of EducationBeijing Key Laboratory of Cardiovascular Receptors ResearchBeijing 100191China Department of Emergency Medicine Peking University Third HospitalBeijing 100191China

BACKGROUND: It is challenging to establish peripheral intravenous access in adult critically patients. This study aims to compare the success rate of the first attempt, procedure time, operator satisfaction with the used devices, pain score, and complications between intraosseous(IO) access and central venous catheterization(CVC) in critically ill Chinese ***: In this prospective clustered randomized controlled trial, eight hospitals were randomly divided into either the IO group or the CVC group. Patients who needed emergency vascular access were included. From April 1, 2017 to December 31, 2018, each center included 12 patients. We recorded the data mentioned ***: A total of 96 patients were enrolled in the study. There were no statistically significant differences between the two groups regarding sex, age, body mass index, or operator satisfaction with the used devices. The success rates of the first attempt and the procedure time were statistically significant between the IO group and the CVC group(91.7% vs. 50.0%, P<0.001;52.0 seconds vs. 900.0 seconds, P<0.001). During the study, 32 patients were conscious. There was no statistically significant difference between the two groups regarding the pain score associated with insertion. There were statistically significant differences between the two groups regarding the pain score associated with IO or CVC infusion(1.5 vs. 0.0, P=0.044). Complications were not observed in the two ***: IO access is a safe, rapid, and effective technique for gaining vascular access in critically ill adults with inaccessible peripheral veins in the emergency departments.

关键词： Intraosseous access Central venous catheterization Success rates Procedure time Pain score

Vasospastic angina with J waves formation in patients with sudden loss of consciousness

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Journal of Geriatric Cardiology 2015年第3期12卷 313-318页

作者： Dan ZHU Yi-Ming LUO Ke-Hu A ling-yun zu Yan-Hui ZHANG Li-Jun GUO Wei GAO Yuan ZHANG Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides Department of Cardiology Peking University Third Hospital Beijing China

Vasospastic 咽峡炎被一根 epicardial 动脉的一个片断的突然的闭塞的血管缩小引起，它能与大量临床的情形介绍。我们报导与 vasospastic 咽峡炎诊断的二个病人的案例，与哪个之一随突然的心脏的拘捕介绍，当时另外的与相对良性的中略... 详细信息

Vasospastic 咽峡炎被一根 epicardial 动脉的一个片断的突然的闭塞的血管缩小引起，它能与大量临床的情形介绍。我们报导与 vasospastic 咽峡炎诊断的二个病人的案例，与哪个之一随突然的心脏的拘捕介绍，当时另外的与相对良性的中略介绍。但是他们俩在活跃局部缺血期间在 ECG 上有 J 波浪形成。vasospastic 咽峡炎的诊断和管理，以及 J 波浪的建议临床的意义在冠的痉挛期间被讨论。

关键词：血管收缩心绞痛痉挛性患者冠状动脉临床意义脑缺血活动性

High formability Mg-Zn-Gd wire facilitates ACL reconstruction via its swift degradation to accelerate intra-tunnel endochondral ossification

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Journal of Magnesium and Alloys 2024年第1期12卷 295-315页

作者： Xuan He Ye Li Hongwei Miao Jiankun Xu Michael Tim-yun Ong Chenmin Wang Lizhen Zheng Jiali Wang Le Huang Haiyue zu Zhi Yao Jie Mi Bingyang Dai Xu Li Patrick Shu-hang yung Guangyin Yuan ling Qin Musculoskeletal Research Laboratory of Department of Orthopaedics&Traumatology and Innovative Orthopaedic Biomaterial and Drug Translational Research Laboratory of Li Ka Shing Institute of Health Sciences The Chinese University of Hong KongHong KongChina National Engineering Research Center of Light Alloy Net Forming School of Materials Science&EngineeringShanghai Jiao Tong UniversityShanghaiChina Department of Orthopaedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Orthopaedic Department Peking University Third HospitalBeijingChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong KongChina

After reconstructing the anterior cruciate ligament(ACL),unsatisfactory bone tendon interface healing may often induce tunnel enlargement at the early healing *** good biological features and high formability,Magnesium-Zinc-Gadolinium(ZG21)wires are developed to bunch the tendon graft for matching the bone tunnel during ***,tensile strength,degradation,and cytotoxicity of ZG21 wire are *** rabbit model is used for assessing the biological effects of ZG21 wire by Micro-CT,histology,and mechanical *** SEM/EDS,immunochemistry,and in vitro assessments are performed to investigate the underlying *** tests demonstrate the high formability of ZG21 wire as surgical ***-CT shows ZG21 wire degradation accelerates tunnel bone formation,and histologically with earlier and more fibrocartilage regeneration at the healing *** mechanical test shows higher ultimate load in the ZG21 *** SEM/EDS presents ZG21 wire degradation triggered calcium phosphate(Ca-P)*** results demonstrate upregulation of Wnt3a,BMP2,and VEGF at the early phase and TGFβ3 and Type II collagen at the late phase of *** vitro tests also confirmed the Ca-P in the metal extract could elevate the expression of Wnt3a,βcatenin,ocn and opn to stimulate *** vivo tests of clinical samples indicated suturing with ZG21 wire did not weaken the ultimate loading of human tendon *** conclusion,the ZG21 wire is feasible for tendon graft *** degradation products accelerated intra-tunnel endochondral ossification at the early healing stage and therefore enhanced bone-tendon interface healing in ACL reconstruction.

关键词： Magnesium wire ACL reconstruction Magnesium alloy Biomaterials Endochondral ossification

Proposing a machine learning approach to analyze and predict basic high-temperature properties of iron ore fines and its factors

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1082-1094页

作者： Qing-ke Sun Yao-zu Wang Jian-liang Zhang Zheng-jian Liu Le-le Niu Chang-dong Shan yun-fei Ma Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic ***,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was ***,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the *** test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after *** trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.

关键词： Iron ore Basic high-temperature property Machine learning Random forest Genetic algorithm

A probabilistic model based on the peak-over-threshold approach for risk assessment of airport controllers’performance

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Journal of Safety Science and Resilience 2024年第1期5卷 110-118页

作者： Lili zu Yijie Lu Min Dong College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Applied Science George Washington UniversityWashington DC 20052USA College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Airport tower control plays an instrumental role in ensuring airport ***,obtaining objective,quantitative safety evaluations is challenging due to the unavailability of pertinent human operation *** study introduces a probabilistic model that combines aircraft dynamics and the peak-over-threshold(POT)approach to assess the safety performance of airport *** applied the POT approach to model reaction times extracted from a radiotelephony dataset via a voice event detection *** model couples the risks of tower control and aircraft operation to analyze the influence of human *** data from radiotele-phony communications and the Base of Aircraft Data(BADA)database,we compared risk levels across *** findings revealed heightened airport control risks under low demand(0.374)compared to typical conditions(0.197).Furthermore,the risks associated with coupling under low demand exceeded those under typical de-mand,with the final approach stage presenting the highest risk(4.929×107).Our model underscores the significance of human factors and the implications of mental disconnects between pilots and controllers for safety ***,these consistent findings affirm the reliability of our probabilistic model as an evaluative tool for evaluating the safety performance of airport tower *** results also illuminate the path toward quantitative real-time safety evaluations for airport controllers within the *** recommend that airport regulators focus on the performance of airport controllers,particularly during the final approach stage.

关键词： Safety evaluation Performance Probabilistic model Task demand Airport controller

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang Zhang zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Cosmological interpretation for the stochastic signal in pulsar timing arrays

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 43-50页

作者： Yu-Mei Wu zu-Cheng Chen Qing-Guo Huang School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Department of Physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangsha 410081China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

The pulsar timing array(PTA)collaborations have recently reported compelling evidence for a stochastic signal consistent with a gravitational-wave *** this paper,we combine the latest data sets from NANOGrav,PPTA,and EPTA to explore cosmological interpretations for the PTA signal from first-order phase transitions,domain walls,and cosmic strings,*** find that the domain wall model is strongly disfavored with the Bayes factors compared with the first-order phase transitions and cosmic strings being 1/90 and 1/189,respectively,breaking the degeneracy among these models in individual data *** also find that:(1)a strong phase transition at temperatures below the electroweak scale is favored,and the bubble collisions make the dominant contribution to the energy density spectrum;(2)a small reconnection probability p<1.55×10^(-1)allowed by strings in(super)string theory is favored at the 95%confidence level,and ground-based detectors can further constrain the parameter space.

关键词： puslar timing arrays gravitational-wave background first-order phase transitions domain walls cosmic strings

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Belief reliability:a scientific exploration of reliability engineering

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Journal of Systems Engineering and Electronics 2024年第3期35卷 619-643页

作者： ZHANG Qingyuan LI Xiaoyang zu Tianpei KANG Rui International Innovation Institute Beihang UniversityHangzhou 311115China Science and Technology on Reliability and Environmental Engineering Laboratory Beijing 100191China School of Reliability Engineering and Systems Engineering Beihang UniversityBeijing 100191China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

This paper systematically introduces and reviews a scientific exploration of reliability called the belief *** with the origin of reliability engineering,the problems of present theories for reliability engineering are summarized as a query,a dilemma,and a ***,through philosophical reflection,we introduce the theoretical solutions given by belief reliability theory,including scientific principles,basic equations,reliability science experiments,and mathematical *** basic methods and technologies of belief reliability,namely,belief reliability analysis,function-oriented belief reliability design,belief reliability evaluation,and several newly developed methods and technologies are sequentially elaborated and *** on the above investigations,we summarize the significance of belief reliability theory and make some prospects about future research,aiming to promote the development of reliability science and engineering.

关键词： belief reliability performance margin reliability experiment chance measure uncertainty