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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme Manufacturing 2024年第3期6卷 458-475页

作者： Nianwei Xu Renke Kang Bi Zhang yuan Zhang Chenxu Wang Yan Bao zhigang dong State Key Laboratory of High-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding

Developing a diagnostic model for predicting prostate cancer: a retrospective study based on Chinese multicenter clinical data

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Asian Journal of Andrology 2024年第1期26卷 34-40页

作者： Chang-Ming Wang Lei yuan Xue-Han Liu Shu-Qiu Chen Hai-Feng Wang Qi-Fei dong Bin Zhang Ming-Shuo Huang zhi-Yong Zhang Jun Xiao Tao Tao Department of Urology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Radiology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Core Facility Center for Medical Sciences The First Affiliated Hospital of USTcDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Urology Affiliated Zhongda Hospital of Southeast UniversityNanjing 210009China Department of Urology Shanghai East HospitalTongji University School of MedicineShanghai 200120China Department of Urology Shanghai Changhai HospitalSecond Military Medical UniversityShanghai 200000China Department of Urology Affiliated Anhui Provincial Hospital of Anhui Medical UniversityHefei 230001China

The overdiagnosis of prostate cancer(PCa)caused by nonspecific elevation serum prostate-specific antigen(PSA)and the overtreatment of indolent PCa have become a global problem that needs to be solved *** aimed to construct a prediction model and provide a risk stratification system to reduce unnecessary *** this retrospective study,clinical data of 1807 patients from three Chinese hospitals were *** final model was built using stepwise logistic regression *** apparent performance of the model was assessed by receiver operating characteristic curves,calibration plots,and decision curve ***,a risk stratification system of clinically significant prostate cancer(csPCa)was created,and diagnosis-free survival analyses were *** multivariable screening and evaluation of the diagnostic performances,a final diagnostic model comprised of the PSA density and Prostate Imaging-Reporting and Data System(PI-RADS)score was *** validation in the development cohort and two external cohorts showed excellent discrimination and ***,we created a risk stratification system using risk thresholds of 0.05 and 0.60 as the cut-off *** follow-up results indicated that the diagnosis-free survival rate for csPCa at 12 months and 24 months postoperatively was 99.7%and 99.4%,respectively,for patients with a risk threshold below O.05 after the initial negative prostate biopsy,which was significantly better than patients with higher *** diagnostic model and risk stratification system can achieve a personalized risk calculation of *** provides a standardized tool for Chinese patients and physicians when considering thenecessity of prostatebiopsy.

关键词： nomogram prostate biopsy prostate cancer Prostate Imaging-Reporting and Data System prostate-specific antigen density

General radical difluoromethylation using difluoroacetic anhydride via photoredox catalysis

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Science China Chemistry 2024年第8期67卷 2637-2646页

作者： Meng He Yankai Yang Heng Zhang zhipeng Guan zhi-Bing dong Hong Yi Aiwen Lei School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430205China College of Chemistry and Molecular Sciences and Institute for Advanced Studies(IAS) Wuhan UniversityWuhan 430072China

CF_(2)H-containing molecules play pivotal roles in diverse fields from medicinal chemistry to materials science. However, the application of existing CF_(2)H reagents as a source of CF_(2)H radical is limited by their reactivity and preparation. Herein, we develop a simple and general visible-light-catalyzed radical difluoromethylation reaction of alkenes, dienes, and heteroaromatics using commercially available, easy-to-handle, and low-cost difluoroacetic anhydride as the CF_(2)H reagent. This scalable protocol enables the convenient synthesis of a range of CF_(2)H-containing compounds under mild conditions, exhibiting a broad substrate scope and functional group tolerance. Potential applications are further demonstrated by gram-scale synthesis, sunlight experiments, derivatization experiments as well as the synthesis of bioactive molecules.

关键词： radical difluoromethylation alkenes/dienes/heteroaromatics difluoroacetic anhydride photoredox

Prevalence,patterns,risk factors and outcomes of peritoneal metastases after laparoscopic hepatectomy for hepatocellular carcinoma:a multicenter study from China

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Hepatobiliary Surgery and Nutrition 2024年第1期13卷 3-15,I0001-I0004页

作者： yuan-Xiang Lu Jian-Ping Zhao Guan-Dou yuan Ming-Gen Hu Chuan-dong Sun Kun-Lun Chen Yao Chen Yong-Yi Zeng zhi-Ying Yang Wan-Guang Zhang Hepatic Surgery Center Tongji Hospital of Tongji Medical College of Huazhong University of Science and TechnologyWuhanChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanningChina Faculty of Hepato-Pancreato-Biliary Surgery Chinese PLA General HospitalBeijingChina Department of Hepatobiliary and Pancreatic Surgery The Affiliated Hospital of Qingdao UniversityQingdaoChina Department of Hepatobiliary and Pancreatic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Department of Radiology Intervention The Affiliated Tumor Hospital of Zhengzhou UniversityHenan Cancer HospitalZhengzhouChina Department of Hepatobiliary Surgery Mengchao Hepatobiliary Hospital of Fujian Medical UniversityFuzhouChina Department of General Surgery China-Japan Friendship HospitalBeijingChina

Background:We aim to investigate the prevalence,patterns,risk factors,and outcomes of peritoneal metastases(PM)after curative laparoscopic hepatectomy(LH)for hepatocellular carcinoma(HCC).Methods:A multicenter cohort of 2,138 HCC patients who underwent curative LH from August 2010 to December 2016 from seven hospitals in China was retrospectively *** incidence of PM following LH was evaluated and compared with that in open hepatectomy(OH)after 1:1 propensity score matching(PSM).Results:PM prevalence was 5.1%(15/295)in the early period[2010-2013],2.6%(47/1,843)in the later period[2014-2016],and 2.9%(62/2,138)in all LH patients,which was similar to 4.0%(59/1,490)in the OH *** recurrence patterns,timing,and treatment did not significantly vary between the LH and OH patients(P>0.05).Multivariate logistic regression revealed that tumor diameter>5 cm,non-anatomical resection,presence of microvascular invasion,and lesions<2 cm from major blood vessels were independent risk factors of PM after *** the 62 cases with PM,26(41.9%)had PM only,34(54.9%)had intrahepatic recurrence(IHR)and PM,and 2(3.2%)had synchronous extraperitoneal metastases(EPM).Patients with resectable PM had a 5-year overall survival(OS)of 65.0%compared to 9.0%for unresectable PM(P=0.001).Conclusions:The prevalence,patterns and independent risk factors of PM were identified for HCC patients after *** was not associated with increased incidence of PM in HCC patients for experienced *** re-excision of PM was associated with prolonged survival.

关键词： Prevalence hepatocellular carcinoma(HCC) peritoneal metastases(PM) laparoscopic hepatectomy(LH) open hepatectomy(OH)

Simulation and reconstruction of particle trajectories in the CEPC drift chamber

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Nuclear Science and Techniques 2024年第8期35卷 9-22页

作者： Meng‑Yao Liu Wei‑dong Li Xing‑Tao Huang Yao Zhang Tao Lin Ye yuan Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The circular electron-positron collider(CEPC)is designed to precisely measure the properties of the Higgs boson,study electroweak interactions at the Z-boson peak,and search for new physics beyond the Standard *** a component of the 4th conceptual CEPC detector,the drift chamber facilitates the measurement of charged *** study implemented a Geant4-based simulation and track reconstruction for the drift *** the simulation,detector construction and response were implemented and added to the CEPC simulation *** development of track reconstruction involves track finding using the combinatorial Kalman filter method and track fitting using the tool of *** the simulated data,the tracking performance was *** results showed that both the reconstruction resolution and tracking efficiency satisfied the requirements of the CEPC experiment.

关键词： CEPC Drift chamber Detector simulation Track reconstruction

Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

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China Foundry 2024年第2期21卷 147-158页

作者： Ning Wang Kai Ma Qiu-da Li Yu-dong yuan Yan-chun Zhao Li Feng School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals Lanzhou 730050China CNNC Nuclear Power Operation and Management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting *** microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal *** results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the ***(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these *** an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then ***,the area fraction initially decreases and then ***,the alloy’s strength and wear resistance decrease,while its plasticity *** Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

Lath-like phases formed at an extremely high temperature in a Mg-RE(RE=rare earth)-Al alloy

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Rare Metals 2024年第8期43卷 3937-3945页

作者： Bo Deng Shu-Hui Lv Qiang Yang dong-Yue Zhao Jun-yuan Fan Xin Qiu School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135China

Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)*** this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 ***-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R *** followed common orientation relationships with Mg matrix as those reported in previous *** addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:***,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.

关键词： Magnesium alloy HAADF-STEM Microstructures Intermetallic particles Orientation relationships Interfaces

The role of lipid metabolism in osteoporosis:Clinical implication and cellular mechanism

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Genes & Diseases 2024年第4期11卷 220-233页

作者： Jing Zhang Wenhui Hu zhi Zou Yuheng Li Fei Kang Jianmei Li Shiwu dong College of Bioengineering Chongqing UniversityChongqing 400044China Department of Biomedical Materials Science College of Biomedical EngineeringArmy Medical University(Third Military Medical University)Chongqing 400038China State Key Laboratory of Trauma and Chemical Poisoning Army Medical University(Third Military Medical University)Chongqing 400038China

In recent years,researchers have become focused on the relationship between lipids and bone metabolism ***,many diseases related to lipid metabolism dis-orders,such as nonalcoholic fatty liver disease,atherosclerosis,obesity,and menopause,are associated with osteoporotic *** has been clinically observed in humans that these lipid metabolism disorders promote changes in osteoporosis-related indicators bone mineral density and bone ***,similar osteoporotic phenotype changes were observed in high-fat and high-cholesterol-induced animal *** lipid metabolism(such as increased oxidized lipids and elevated plasma cholesterol)affects bone microenvironment ho-meostasis via cross-organ communication,promoting differentiation of mesenchymal stem cells to adipocytes,and inhibiting commitment towards ***,disturbances in lipid metabolism affect the bone metabolism balance by promoting the secretion of cyto-kines such as receptor activator of nuclear factor-kappa B ligand by osteoblasts and stimulating the differentiation of ***,this review addresses the possible link be-tween lipid metabolism disorders and osteoporosis and elucidates the potential modulatory mechanisms and signaling pathways by which lipid metabolism affects bone metabolism *** also summarize the possible approaches and prospects of intervening lipid meta-bolismforosteoporosistreatment.

关键词： Bone homeostasis Cross-organ communication Lipid metabolism Osteoclast Osteoporosis

On the Characteristic Length Scale for the Synthetic Turbulence Based on the Spalart-Allmaras Model

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 122-145页

作者： Qilong Guo Pengxin Liu Chen Li dong Sun Xianxu yuan State Key Laboratory of Aerodynamics MianyangSichuan 621000China

In the hybrid RANS-LES simulations,proper turbulent fluctuations should be added at the RANS-to-LES interface to drive the numerical solution restoring to a physically resolved turbulence as rapidly as *** turbulence generation methods mostly need to know the distribution of the characteristic length scale of the background RANS model,which is important for the recovery *** approximation of the length scale for the Spalart-Allmaras(S-A)model is not a trivial issue since the model’s one-equation *** a direct analogy,the approximations could be obtained from the definition of the Prandtl’s mixing ***,this paper proposes a new algebraic expression to approximate the intrinsic length scale of the S-A *** underlying transportation mechanism of S-A model are largely exploited in the derivation of this new *** new proposed expression is employed in the generation of synthetic turbulence to perform the hybrid RANS-LES simulation of canonical wall-bounded turbulent *** comparisons demonstrated the feasibility and improved performance of the new length scale on generating synthetic turbulence at the LES inlet.

关键词： Length scale synthetic turbulence hybrid RANS-LES Spalart-Allmaras model