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c-BN含量对(Ti,W)C/WC/Co金属陶瓷刀具材料力学性能的影响

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人工晶体学报 2019年第12期48卷 2323-2329页

作者：方斌李德芃李祥龙解传娣张国强许崇海衣明东齐鲁工业大学(山东省科学院) 机械与汽车工程学院济南250353 莱芜职业技术学院山东省粉末冶金先进制造实验室济南271100 山东大学机械工程学院济南250061

采用真空热压烧结工艺制备了(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料,分析了(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料的微观结构、元素成分和物相组成,研究了不同含量c-BN对(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料微观结构和力学性能的影响。研究... 详细信息

采用真空热压烧结工艺制备了(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料,分析了(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料的微观结构、元素成分和物相组成,研究了不同含量c-BN对(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料微观结构和力学性能的影响。研究结果表明:适量添加c-BN能有效细化颗粒,减少气孔等缺陷,提高材料的相对密度,(Ti,W)C/WC/c-BN/Co金属陶瓷刀具材料的断裂模式为穿/沿晶混合断裂模式;当c-BN含量为1wt%时,(Ti,W)C/WC/c-BN/Co金属陶瓷刀具的综合力学性能最优,其抗弯强度、断裂韧性和维氏硬度分别为769.32±10.21 MPa、6.69±0.18 MPa·m^1/2和22.83±0.46 GPa。

关键词： c-BN 金属陶瓷刀具材料微观结构力学性能

Mediating role of health literacy in the relationship between social isolation and psychological distress among pre-frail older adults

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World Journal of Psychiatry 2025年第1期15卷 137-144页

作者： Juan Fang Li-Hui Li ming-Qian He Yue Ji dong-Yan Lu Li-Bing Zhang Jin-Lan Yao School of Medicine Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Frailty has become a significant public health *** recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in *** social isolation of pre-frail older adults can impact their psychological *** To explore the mediating effect of health literacy between social isolation and psychological distress among communitydwelling older adults with *** This descriptive cross-sectional study was conducted with 254 pre-frail older individuals aged 60 years and *** isolation,health literacy,and psycholo-gical distress were comprehensively measured using the Lubben Social Network Scale-6,12-item Short-Form Health Literacy Questionnaire,and the Kessler Psy-chological Distress *** were evaluated using the SPSS 27.0 package program and the PROCESS macro *** statistical analyses,correlation analyses,and bootstrap mediation tests were used to assess associations between the *** The results showed that social isolation had an effect on health literacy among pre-frail older adults(β=0.240,P<0.001),social isolation impact on psycho-logical distress pre-frail older adults(β=-0.415,P<0.001);health literacy was identified effect on psychological distress among pre-frail older persons(β=-0.307,P<0.001).Health literacy partially mediated the relationship between social isolation and psychological distress among community-dwelling older adults with pre-frailty,with a mediation effect of-0.074,accounting for 17.83%of the total effect.

关键词： Frail Ageing Psychological distress Health literacy Social isolation

Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng Hai-Hui Jiang Hui-Li Kang yi Jiang Hua-Wei Zhang Xiao-Mei Song Yu-Ze Li Wen-Li Huang dong-dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

Review of Ex Vivo Cardiac Electrical Mapping and Intelligent Labeling of Atrial Fibrillation Substrates

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Chinese Journal of Electrical Engineering 2023年第1期9卷 93-103页

作者： yi Chang ming dong Bin Wang ming Ren Lihong Fan School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China The First Affiliated Hospital of Xi’an Jiaotong University Xi’an 710061China

With the development of computer hardware and the growth of clinical database,tremendous progress has been made in the application of deep learning to electrocardiographic data,which provides new ideas for the ex vivo cardiac electrical mapping of atrial fibrillation(AF)*** AF mechanism and current status of AF substrate research are first ***,the advantages and limitations of cardiac electrophysiological mapping techniques are ***,the application of deep learning to electrocardiogram(ECG)data is reviewed,the problems with the ex vivo intelligent labeling of an AF substrate and the possible solutions are discussed,an outlook on future development is provided.

关键词： Catheter ablation atrial fibrillation substrate three-dimensional mapping deep learning

Success of intravenous immunoglobulin and steroids in managing severe COVID-19 following lung transplantation:A case report

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World Journal of Transplantation 2025年第1期15卷 178-184页

作者： Yen-Shou Kuo Kuan-Hsun Lin ying-yi Chen Yuan-ming Tsai Ti-Hui Wu Hsu-Kai Huang Tsai-Wang Huang Division of Thoracic Surgery Department of SurgeryTri-Service General HospitalNational Defense Medical CenterTaipei 114202Taiwan

BACKGROUND Coronavirus disease 2019(COVID-19)pneumonia with severe septic shock and acute respiratory distress syndrome(ARDS)are critical illnesses for patients following *** immunoglobulin(IVIG)plays a role in both immune support and inflammation control,especially in immunocompromised *** case report describes the first successful experience using IVIG and pulse steroids to manage this critical condition following lung *** SUMMARY A 65-year-old male patient reported a history of chronic obstructive pulmonary disease and poor lung function and received bilateral sequential lung ***,he developed COVID-19 pneumonia,severe septic shock,and *** recovered from this critical condition after empirical antibiotics administration and veno-venous extracorporeal membrane oxygenation,in addition to IVIG and pulse *** IVIG is a valuable adjunct in managing severe sepsis in lung transplant recipients after COVID-19 *** aim,for the first time,to report the success of such a management approach for COVID-19 ARDS and sepsis in the post-lung transplant *** further investigations,this is a starting point for wider analysis of such an approach in this setting and consequently helps guide clinical practice for such a challenging patient population moving forward.

关键词： COVID-19 Septic shock Intravenous immunoglobulin Lung transplantation Post-transplant complications Case report

Swelling of Spherical Polyelectrolyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1386-1392,I0009页

作者： ming-Yu Duan Jia-dong Chen yi-ming Liu Zhao-Feng Peng Guang Chen Department of Advanced Manufacturing and Robotics College of EngineeringPeking UniversityBeijing 100871China

Polyelectrolyte(PE)gels,distinguished by their unique stimuli-responsive swelling behavior,serve as the basis of broad applications,such as artificial muscles and drug *** this work,we present a theoretical model to analyze the electrostatics and its contribution to the swelling behavior of PE gels in salt *** minimizing the free energy of PE gels,we obtain two distinct scaling regimes for the swelling ratio at equilibrium with respect to the salt *** compare our predictions for the swelling ratio with experimental measurements,which show excellent *** addition,we employ a finite element method to assess the applicability range of our theoretical model and *** anticipate that our model will also provide valuable insights into drug adsorption and release,deformation of red blood cells,4D printing and soft robotics,where the underlying mechanism of swelling remains enigmatic.

关键词： Gels Polyelectrolytes Swelling Stimuli-responsive Electrostatic interaction Cell model

Analysis of imbibition of n-alkanes in kerogen slits by molecular dynamics simulation for characterization of shale oil rocks

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Petroleum Science 2022年第3期19卷 1236-1249页

作者： Qian Sang Xin-yi Zhao Hui-Min Liu ming-Zhe dong Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Management Center of Oil&Gas Exploration of Shengli Oilfield Branch Company SINOPECDongying257001ShandongChina Department of Chemical and Petroleum Engineering University of CalgaryCalgaryABCanadaT2N 1N4

Shale oil formations contain both inorganic and organic *** organic matter holds both free oil in the pores and dissolved oil within the kerogen *** free oil flow in organic pores and the dissolved oil diffusion in kerogen molecules are coupled *** molecular flow of free n-alkanes is an important process of shale oil accumulation and *** study the dynamics of imbibition process of n-alkane molecules into kerogen slits,molecular dynamics(MD)simulations are *** of slit width,temperature,and n-alkane types on the penetration speed,dynamic contact angle,and molecular conformations were *** showed that molecular transportation of n-alkanes is dominated by molecular structure and molecular motion at this *** space-confinement conformational changes of molecules slow down the filling speeds in the narrow *** n-alkane molecules with long carbon chains require more time to undergo conformational *** high content of short-chain alkanes and high temperature facilitate the flow of alkane mixtures in kerogen *** obtained from this study are useful for understanding the underlying nanoscale flow mechanism in shale formations.

关键词： Molecular flow Imbibition n-Alkane Kerogen slit Molecular dynamics simulation

Scattering of Tollmien-Schlichting waves by localized roughness in transonic boundary layers

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 1105-1124页

作者： ming dong Department of Mechanics Tianjin UniversityTianjin 300072China Laboratory for High-Speed Aerodynamics Tianjin UniversityTianjin 300072China

The laminar-turbulent transition in boundary-layer flows is often affected by wall imperfections, because the latter may interact with either the freestream perturbations or the oncoming boundary-layer instability modes, leading to a modification of the accumulation of the normal modes. The present paper particularly focuses on the latter mechanism in a transonic boundary layer, namely, the effect of a two-dimensional(2 D) roughness element on the oncoming Tollmien-Schlichting(T-S) modes when they propagate through the region of the rapid mean-flow distortion induced by the roughness. The wave scattering is analyzed by adapting the local scattering theory developed for subsonic boundary layers(WU, X. S. and dong, M. A local scattering theory for the effects of isolated roughness on boundary-layer instability and transition: transmission coefficient as an eigenvalue. Journal of Fluid Mechanics, 794, 68–108(2006)) to the transonic regime, and a transmission coefficient is introduced to characterize the effect of the roughness. In the sub-transonic regime, in which the Mach number is close to, but less than, 1, the scattering system reduces to an eigenvalue problem with the transmission coefficient being the eigenvalue;while in the super-transonic regime, in which the Mach number is slightly greater than 1, the scattering system becomes a high-dimensional group of linear equations with the transmission coefficient being solved afterward. In the largeReynolds-number asymptotic theory, the K′arm′an-Guderley parameter is introduced to quantify the effect of the Mach number. A systematical parametric study is carried out,and the dependence of the transmission coefficient on the roughness shape, the frequency of the oncoming mode, and the K′arm′an-Guderley parameter is provided.

关键词： boundary layer scattering instability Tollmien-Schlichting(T-S)wave triple deck

Modeling turbulent heat fluxes over Arctic sea ice using a maximum-entropy-production approach

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Advances in Climate Change Research 2021年第4期12卷 517-526页

作者： ZHANG yi-ming SONG Mi-Rong dong Chang-ming LIU Ji-Ping School of Marine Science Nanjing University of Information Science and TechnologyNanjing210044China LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519000China Department of Atmospheric and Environmental Sciences University at AlbanyState University of New YorkAlbanyNY12222USA

Recently,an algorithm of surface turbulent heat fluxes over snow/sea ice has been developed based on the theory of maximum entropy production(MEP),which is fundamentally different from the bulk flux algorithm(BF)that has been used in sea ice models for a few *** this study,we first assess how well the MEP algorithm captures the observed variations of turbulent heat fluxes over Arctic sea *** is found that the calculated heat fluxes by the MEP method are in good agreement with in-situ observations after considering the absorption of incoming radiation in a snow/ice surface layer with infinitesimal *** then investigate the effects of two different schemes(MEP ***)in the sea ice model of CICE6 on simulated turbulent heat fluxes and sea ice processes in the Arctic *** results show that the two different schemes give quite different representations of seasonal variations of heat fluxes,particularly for sensible heat fluxes in *** heat fluxes simulated by the MEP produce weak cooling effect on the ice surface in summer,whereas the BF generates a warming *** a result,compared to the BF,the MEP leads to a reduced seasonal cycle of Arctic sea ice mass flux by modulating snow-to-ice conversion,basal ice growth,surface ice melt and basal ice melt.

关键词： Sea ice modeling Turbulent heat fluxes Maximum-entropy-production Mass flux