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Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research(International) 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu Zhou-hua Jiang hua-bing li Rui Zhang Hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh techniques.The results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width increase.Meanwhile,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium analysis.As melt rate increases,both the molten pool depth and the mushy width increase.It is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the mold.The nonlinear increment in sensible heat leads to a nonlinear increase in the mushy width.In addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then increases.When melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time

Association between abnormal default mode network homogeneity and sleep disturbances in major depressive disorder

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General Psychiatry 2024年第2期37卷 234-241页

作者： Muzhi huang Yangpan Ou huabing li Feng liu Ping li Jingping Zhao bing Lang Wenbin Guo Department of Psychiatry The Second Xiangya Hospital of Central South University National Clinical Research Center for Mental Disordersand National Center for Mental DisordersChangshaHunanChina Department of Radiology The Second Xiangya Hospital of Central South UniversityChangshaHunanChina Department of Radiology Tianjin Medical University General HospitalHepingTianjinChina Qiqihar Medical University QiqihaerHeilongjiangChina

Background Sleep disturbance is a common comorbidity of major depressive disorder(MDD).However,network homogeneity(NH)changes of the default mode network(DMN)in MDD with sleep disturbances are unclear.Aims The purpose of this study was to probe the abnormal NH in the DMN in MDD with sleep disturbances and to reveal the differences between MDD with or without sleep disturbances.Methods Twenty-four patients with MDD and sleep disturbances(Pa_s),33 patients with MDD without sleep disturbances(Pa_ns)and 32 healthy controls(HCs)were recruited in this study.Resting-state functional imaging data were analysed using NH.Results Compared with Pa_ns and HCs,Pa_s showed decreased NH in the left superior medial prefrontal cortex and increased NH in the right precuneus.There was a negative correlation between NH in the left superior medial prefrontal cortex and sleep disturbances(r=−0.42,p=0.001)as well as a positive correlation between NH in the right precuneus and sleep disturbances(r=0.41,p=0.002)in patients with MDD.Conclusions MDD with sleep disturbances is associated with abnormal NH in the DMN,which could differentiate pa_s from pa_ns.The DMN may play a crucial role in the neurobiological mechanisms of MDD with sleep disturbances.

关键词： sleep medial cortex

Vinyltrimethylsilane as a novel electrolyte additive for improving interfacial stability of li-rich cathode working in high voltage

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Chinese Chemical Letters 2024年第2期35卷 534-538页

作者： bing Jiang Hao li Bi Luo Lehao liu lihua Chu Qiaobao Zhang Meicheng li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of New EnergyNorth China Electric Power UniversityBeijing 102206China State Key Laboratory of Physical Chemistry of Solid Surfaces College of MaterialsXiamen UniversityXiamen 361005China

Boosting the interfacial stability between electrolyte and li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of li-rich cathode materials for high-performance li-ion batteries.In this work,vinyltrimethylsilane as a new type of organic silicon electrolyte additive is studied to address the interfacial instability of li-rich cathode material at high operating voltage.The cells using vinyltrimethylsilane additive shows the high capacity retention of 73.9%after 300 cycles at 1 C,whereas the cells without this kind of additive only have the capacity retention of 58.9%.The improvement of stability is mainly attributed to the additive helping to form a more stable surface film for li-rich cathode material,thus avoiding direct contact between the electrolyte and the cathode material,slowing down the dissolution of metal ions and the decomposition of the electrolyte under high operating voltage.Our findings in this work shed some light on the design of stable cycling performance of li-rich cathode toward advanced li-ion batteries.

关键词： Vinyltrimethylsilane Electrolyte additive li-rich cathode Interfacial stability Capacity retention

Microbiome changes in esophageal cancer:implications for pathogenesis and prognosis

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Cancer Biology & Medicine 2024年第2期21卷 163-174页

作者： Yi li bing Wei Xia Xue Hongle li Jun li Department of Molecular Pathology Clinical Pathology CenterAffiliated Cancer Hospital of Zhengzhou University and Henan Cancer HospitalZhengzhou 450003China Henan Key Laboratory of Molecular Pathology Zhengzhou 450003China Henan Key Laboratory of Helicobacter pylori&Microbiota and Gastrointestinal Cancer Marshall Medical Research CenterThe Fifth Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Esophageal cancer(EC)is an aggressive malignancy with a poor prognosis.Various factors,including dietary habits,and antacid and antibiotic use,have been shown to influence the esophageal microbiome.Conversely,enrichment and diversity of the esophageal microbiome can also impact its function.Recent studies have revealed prevalent changes in the esophageal microbiome among patients with EC,thus suggesting the potential contribution of the esophageal microbiome to EC development.Additionally,distinct microbiome compositions have been observed in patients with different responses to radiotherapy and chemotherapy,indicating the role of the esophageal microbiome in modulating treatment outcomes.In this review,we have examined previous studies on the esophageal microbiome in healthy individuals and patients with EC or other esophageal diseases,with a focus on identifying microbial communities associated with EC pathogenesis and prognosis.Understanding the role of the microbiome in EC may aid in early detection and optimized treatment strategies,ultimately leading to better outcomes for patients.

关键词： Esophageal cancer microbiome dysbiosis microenvironment carcinogenesis

Quantum Neural Network for Quantum Neural Computing

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Research 2024年第1期2023卷 71-80页

作者： Min-Gang Zhou Zhi-Ping liu hua-Lei Yin Chen-Long li Tong-Kai Xu Zeng-bing Chen National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China MatricTime Digital Technology Co.Ltd. Nanjing 211899China

Neural networks have achieved impressive breakthroughs in both industry and academia.How to effectively develop neural networks on quantum computing devices is a challenging open problem.Here,we propose a new quantum neural network model for quantum neural computing using(classically controlled)single-qubit operations and measurements on real-world quantum systems with naturally occurring environment-induced decoherence,which greatly reduces the difficulties of physical implementations.Our model circumvents the problem that the state-space size grows exponentially with the number of neurons,thereby greatly reducing memory requirements and allowing for fast optimization with traditional optimization algorithms.We benchmark our model for handwritten digit recognition and other nonlinear classification tasks.The results show that our model has an amazing nonlinear classification ability and robustness to noise.Furthermore,our model allows quantum computing to be applied in a wider context and inspires the earlier development of a quantum neural computer than standard quantum computers.

关键词： quantum thereby breakthrough

Electrochemical filtration for drinking water purification:A review on membrane materials,mechanisms and roles

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Journal of Environmental Sciences 2024年第7期141卷 102-128页

作者： Yuying Qi Donghao li Shixuan Zhang Fengxiang li Tao hua College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationTianjin 300350China Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China

Electrochemical filtration can not only enrich low concentrations of pollutants but also produce reactive oxygen species to interact with toxic pollutants with the assistance of a power supply,making it an effective strategy for drinking water purification.In addition,the application of electrochemical filtration facilitates the reduction of pretreatment procedures and the use of chemicals,which has outstanding potential for maximizing process simplicity and reducing operating costs,enabling the production of safe drinking water in smaller installations.In recent years,the research on electrochemical filtration has gradually increased,but there has been a lack of attention on its application in the removal of low concentrations of pollutants from low conductivity water.In this review,membrane substrates and electrocatalysts used to improve the performance of electrochemical membranes are briefly summarized.Meanwhile,the application prospects of emerging single-atom catalysts in electrochemical filtration are also presented.Thereafter,several electrochemical advanced oxidation processes coupled with membrane filtration are described,and the related working mechanisms and their advantages and shortcomings used in drinking water purification are illustrated.Finally,the roles of electrochemical filtration in drinking water purification are presented,and the main problems and future perspectives of electrochemical filtration in the removal of low concentration pollutants are discussed.

关键词： Electrochemical filtration Drinking water Conductive membrane Low concentration Electrocatalyst

Triceps skinfold thickness trajectories and the risk of all-cause mortality:A prospective cohort study

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World Journal of Clinical Cases 2024年第15期12卷 2568-2577页

作者： Na Yang li-Yun He Zi-Yi li Yu-Cheng Yang Fan Ping ling-ling Xu Wei li hua-bing Zhang Yu-Xiu li Department of Endocrinology Key Laboratory of Endocrinology of National Health CommissionPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

BACKGROUND The measurement of triceps skinfold(TSF)thickness serves as a noninvasive metric for evaluating subcutaneous fat distribution.Despite its clinical utility,the TSF thickness trajectories and their correlation with overall mortality have not been thoroughly investigated.AIM To explore TSF thickness trajectories of Chinese adults and to examine their associations with all-cause mortality.METHODS This study encompassed a cohort of 14747 adults sourced from the China Health and Nutrition Survey.Latent class trajectory modeling was employed to identify distinct trajectories of TSF thickness.Subjects were classified into subgroups reflective of their respective TSF thickness trajectory.We utilized multivariate Cox regression analyses and mediation examinations to explore the link between TSF thickness trajectory and overall mortality,including contributory factors.RESULTS Upon adjustment for multiple confounding factors,we discerned that males in the‘Class 2:Thin-stable’and‘Class 3:Thin-moderate’TSF thickness trajectories exhibited a markedly reduced risk of mortality from all causes in comparison to the‘Class 1:Extremely thin’subgroup.In the mediation analyses,the Geriatric Nutritional Risk Index was found to be a partial intermediary in the relationship between TSF thickness trajectories and mortality.For females,a lower TSF thickness pattern was significantly predictive of elevated all-cause mortality risk exclusively within the non-elderly cohort.CONCLUSION In males and non-elderly females,lower TSF thickness trajectories are significantly predictive of heightened mortality risk,independent of single-point TSF thickness,body mass index,and waist circumference.

关键词： Triceps skinfold thickness Trajectory All-cause mortality Body mass index Geriatric Nutritional Risk Index

For Mega-Constellations: Edge Computing and Safety Management Based on Blockchain Technology

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China Communications 2024年第2期21卷 59-73页

作者： Zhen Zhang bing Guo Chengjie li College of Computer Science Sichuan UniversityChengdu 610064China The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and TechnologySouthwest Minzu UniversityChengdu 610225China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In mega-constellation Communication Systems, efficient routing algorithms and data transmission technologies are employed to ensure fast and reliable data transfer. However, the limited computational resources of satellites necessitate the use of edge computing to enhance secure communication.While edge computing reduces the burden on cloud computing, it introduces security and reliability challenges in open satellite communication channels. To address these challenges, we propose a blockchain architecture specifically designed for edge computing in mega-constellation communication systems. This architecture narrows down the consensus scope of the blockchain to meet the requirements of edge computing while ensuring comprehensive log storage across the network. Additionally, we introduce a reputation management mechanism for nodes within the blockchain, evaluating their trustworthiness, workload, and efficiency. Nodes with higher reputation scores are selected to participate in tasks and are appropriately incentivized. Simulation results demonstrate that our approach achieves a task result reliability of 95% while improving computational speed.

关键词： blockchain consensus mechanism edge computing mega-constellation reputation management

Dipeptidyl peptidase-4 inhibitors and the risk of infection: A systematic review and meta-analysis of cardiovascular outcome trials

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World Journal of Diabetes 2024年第5期15卷 1011-1020页

作者： Na Yang li-Yun He Peng liu Zi-Yi li Yu-Cheng Yang Fan Ping ling-ling Xu Wei li hua-bing Zhang Yu-Xiu li Department of Endocrinology Key Laboratory of Endocrinology of National Health CommissionPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Endocrinology The First Affiliated Hospitaland College of Clinical Medicine of Henan University of Science and TechnologyLuoyang 471000Henan ProvinceChina

BACKGROUND Since adverse events during treatment affect adherence and subsequent glycemic control,understanding the safety profile of oral anti-diabetic drugs is imperative for type 2 diabetes mellitus(T2DM)therapy.AIM To evaluate the risk of infection in patients with T2DM treated with dipeptidyl-peptidase 4(DPP-4)inhibitors.METHODS Electronic databases were searched.The selection criteria included randomized controlled trials focused on cardiovascular outcomes.In these studies,the effects of DPP-4 inhibitors were directly compared to those of either other active anti-diabetic treatments or placebo.Six trials involving 53616 patients were deemed eligible.We calculated aggregate relative risks employing both random-effects and fixed-effects approaches,contingent upon the context.RESULTS The application of DPP-4 inhibitors showed no significant link to the overall infection risk[0.98(0.95,1.02)]or the risk of serious infections[0.96(0.85,1.08)],additionally,no significant associations were found with opportunistic infections[0.69(0.46,1.04)],site-specific infections[respiratory infection 0.99(0.96,1.03),urinary tract infections 1.02(0.95,1.10),abdominal and gastrointestinal infections 1.02(0.83,1.25),skin structure and soft tissue infections 0.81(0.60,1.09),bone infections 0.96(0.68,1.36),and bloodstream infections 0.97(0.80,1.18)].CONCLUSION This meta-analysis of data from cardiovascular outcome trials revealed no heightened infection risk in patients undergoing DPP-4 inhibitor therapy compared to control cohorts.

关键词： T2DM drugs treatment