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Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1426-1436页

作者： Ying Gao ce Zhang Jiazhen Zhang Xin lu Beijing Advanced Innovation center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsInstitute for Advanced Ma-terials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Engineering Research center for Advanced Rolling Technology National Engineering Research Center for Flat Rolling EquipmentInstitute of Engin-eering TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot rolling.The microstructure and mechanical properties under different process paramet-ers were investigated.Optical microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening mechanism.The results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering temperature.The block was hot rolled at 1200℃ with an 80%reduction under only two passes without annealing.The strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain boundaries.After hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems.

关键词： elemental powder powder metallurgy titanium alloy hot rolling strength and plasticity

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Comparison of time trends in the incidence of primary liver cancer between China and the United States: an age-period-cohort analysis of the Global Burden of Disease 2019

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Chinese Medical Journal 2022年第17期135卷 2035-2042页

作者： Zhiyong Zou Zuofeng Zhang ce lu Hui Wang Iinstitute of Child and Adolescent Health School of Public HealthPeking University Health Science CenterBeijing 100191China Department of Epidemiology Fielding School of Public HealthUniversity of CaliforniaLos AngelesCAUSA Department of Epidemiology School of Public HealthNanjing Medical UniversityNanjngJjiangsu 21161China Department of Maternal and Child Health School of Public HealthPeking University Health Science CenterBeijing 100191China

Background::China and the United States(US)ranked first and third in terms of new liver cancer cases and deaths globally in 2020.Therefore,a comprehensive assessment of trends in the incidence of primary liver cancer with four major etiological factors between China and the US during the past 30 years with age-period-cohort(APC)analyses is warranted.Methods::Data were obtained from the Global Burden of Disease 2019,and period/cohort relative risks were estimated by APC modeling from 1990 to 2019.Results::In 2019,there were 211,000 new liver cancer cases in China and 28,000 in the US,accounting for 39.4%and 5.2%of global liver cancer cases,respectively.For China,the age-standardized incidence rate(ASIR)consecutively decreased before 2005 but increased slightly since then,whereas the ASIR continuously increased in the US.Among the four etiological factors of liver cancer,the fastest reduction in incidence was observed in hepatitis B virus-related liver cancer among Chinese women,and the fastest increase was in nonalcoholic steatosis hepatitis(NASH)-related liver cancer among American men.The greatest reduction in the incidence of liver cancer was observed at the age of 53 years in Chinese men(-5.2%/year)and 33 years in Chinese women(-6.6%/year),while it peaked at 58 years old in both American men and women(4.5%/year vs.2.8%/year).Furthermore,the period risks of alcohol-and NASH-related liver cancer among Chinese men have been elevated since 2013.Simultaneously,leveled-off period risks were observed in hepatitis C viral-related liver cancer in both American men and women.Conclusions::Currently,both viral and lifestyle factors have been and will continue to play an important role in the time trends of liver cancer in both countries.More tailored and efficient preventive strategies should be designed to target both viral and lifestyle factors to prevent and control liver cancer.

关键词： Alcohol use-related liver cancer China Global Burden of Disease Hepatitis Hepatitis B virus Hepatitis C Incidence Liver neoplasms Life Style Middle aged Non-alcoholic fatty liverdisease United States

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Temporal and Spectral Characteristics of Persistent Emission and Special Bursts of Magnetar SGR J1935+2154 Based on Insight-HXMT

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Research in Astronomy and Astrophysics 2024年第6期24卷 227-235页

作者： Xue-Feng lu Li-Ming Song Ming-Yu Ge Shuang-Nan Zhang Jin-lu Qu ce Cai Cong-Zhan Liu Cheng-Kui Li Yu-Cong Fu Ying-Chen Xu Key Laboratory of Particle Astrophysics Institute of High Energy Physics University of Chinese Academy of Sciences Chinese Academy of Sciences College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Department of Astronomy Beijing Normal University

In October 2022, the magnetar SGR J1935+2154 entered the active outburst state. During the episode, the InsightHXMT satellite carried out a long observation that lasted for 20 days. More than 300 bursts were detected, and a certain amount of persistent radiation signals were also accumulated. This paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT data. At the same time, the burst phase distribution characteristics, spectral lag results of burst, the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are reported. We found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+2154. The observed zero-lag burst does not have a unique spectrum. The time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the burst. We also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile.

关键词： dense matter magnetic fields radiation mechanisms: general

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融合处理速度和加速度记录的地震检测模型及其在新丰江水库的应用

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地球科学 2024年第2期49卷 469-479页

作者：蒋策吕作勇房立华中国地震局地球物理研究所北京100081 广东省地震局广东广州510070 中国地震局震源物理重点实验室北京100081

随着国家地震烈度速报与预警工程的建设,加速度记录在地震科学中将得到越来越多的应用.但目前的地震检测模型多使用速度记录训练,对加速度记录的检测效果较差.利用广东地震台网数据,训练得到了可检测速度记录的PhaseNet_GD模型和检测加... 详细信息

随着国家地震烈度速报与预警工程的建设,加速度记录在地震科学中将得到越来越多的应用.但目前的地震检测模型多使用速度记录训练,对加速度记录的检测效果较差.利用广东地震台网数据,训练得到了可检测速度记录的PhaseNet_GD模型和检测加速度记录的PhaseNet_ITS模型.在此基础上,结合GaMMA震相关联和HYPOSAT地震定位方法,发展了一套新的地震数据智能处理流程,并处理了2023年新丰江水库M_(L)4.8地震序列,检测出的事件数量是人工目录的3.8倍,匹配率为93.2%,误检测率为0.38%.这一系统可快速产出完备性高、高精度的地震目录,为水库地震监测和区域地震台网的数据实时处理提供技术支撑.

关键词：区域台网深度学习地震检测 PhaseNet 新丰江水库水库地震

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Separation of La(Ⅲ),ce(Ⅳ)and Ca(Ⅱ)from bastnaesite using acidic phosphonic chitosan and rotating disk membrane

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Journal of Rare Earths 2024年第5期42卷 995-1000,I0007页

作者： Dandan lu Wenhui Li Linlin Fan Yunren Qiu School of Chemistry and Chemical Engineering Central South UniversityChangsha410083China

The separation of rare earths is difficult due to their similar properties and the complex characteristics of associated vein o res.Complexation-ultrafiltration(CUF)and shear induced o rderly dissociation coupling with ultrafiltration(SIODUF)were used to separate metal ions(M,M=La(Ⅲ),ce(Ⅳ)and Ca(Ⅱ))from simulated bastnaesite leaching solution using acidic phosphonic chitosan(aPCS)and rotating disk membrane.Effect of simultaneous removal of metallic ions was investigated by CUF,and suitable conditions were obtained for C/M 10.0(mass ratio of complexant to metal ions)and pH 5.0.The shear stabilities of aPCS-M complexes were explored at different pH values and the results show that the complexes can dissociate at a certain rotational speed,the critical one.The critical s hear rates of aPCS-La,aPCS-ce and aPCS-Ca complexes at pH 5.0 were calculated as 1.42×10^(5).1.69×10^(5) and 9.75×10^(4) s^(-1),respectively.The order of complexes shear stability is aPCS-Ca aPCS-Lace.The high selective separation of M and regeneration of aPCS were achieved by SIODUF in the light of the difference of aPCSM complexes shear stabilities.The separation coefficientsβLa/ce andβCa/La reach 31.2 and 53.9,respectively.

关键词： Bastnaesite Rare earths Complexation-ultrafiltration Acidic phosphonic chitosan Rotating disk membrane

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基于PSO-CNN-XGBoost水下柱形装药峰值超压预测

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兵工学报 2024年第5期45卷 1602-1612页

作者：刘芳李士伟卢熹郭策安沈阳理工大学理学院辽宁沈阳110159 沈阳理工大学辽宁省兵器工业智能优化与控制重点实验室辽宁沈阳110159 沈阳理工大学自动化与电气工程学院辽宁沈阳110159 沈阳理工大学装备工程学院辽宁沈阳110159

为探索水下柱形装药结构、爆距等参数与水下柱形装药峰值超压的关系,将装药样本数据视为二维数据,建立粒子群优化(Particle Swarm Optimization,PSO)算法、一维卷积神经网络(1D Convolutional Neural Network,1DCNN)和极端梯度提升(Extr... 详细信息

为探索水下柱形装药结构、爆距等参数与水下柱形装药峰值超压的关系,将装药样本数据视为二维数据,建立粒子群优化(Particle Swarm Optimization,PSO)算法、一维卷积神经网络(1D Convolutional Neural Network,1DCNN)和极端梯度提升(Extreme Gradient Boosting,XGBoost)的水下柱形装药峰值超压融合预测算法。采用相关性分析与数据可视化方法,分析装药结构参数、爆距与峰值超压之间的关联关系。设计1DCNN深度网络挖掘不同长径比、爆距等参数与峰值超压之间的纵向时序关系。运用XGBoost算法寻找装药结构参数、爆距与峰值超压之间的横向非线性关系,提升小样本数据的预测精度。使用PSO算法优化1DCNN和XGBoost的超参数,获得最优算法结构。研究结果表明,在包含10种智能算法的对比实验中,PSO-CNN-XGBoost水下柱形装药峰值超压预测算法在精度、稳定性、拟合程度上均高于其他模型。

关键词：水下柱形装药长径比爆距峰值超压粒子群优化算法一维卷积神经网络极端梯度提升

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Evaluation of Interferon-Gamma Release Assay Testing and Tuberculin Skin Test for Early Diagnosis of Tuberculosis in Children and Adolescents

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Open Journal of Pediatrics 2024年第3期14卷 558-567页

作者： Yelda Sorguç Miray Çelebi Yılmaz Yüce Ayhan Yakup Yaman Şener Tulumoğlu Aybüke Akaslan Kara İlker Devrim University of Health Sciences Dr. Beh&#231et Uz Child Disease and Pediatric Surgery Training and Research Hospital Medical Microbiology &#304zmir T&#252rkiye Department of Pediatric Infectious Diseases University of Health Sciences Dr. Beh&#231et Uz Child Disease and Pediatric Surgery Training and Research Hospital &#304zmir T&#252rkiye

Background: This study aimed to evaluate the diagnostic value of interferon-γ release assay (IGRA), a sensitive microbiological diagnostic method, in children and adolescents with suspected tuberculosis in a country with a high burden of tuberculosis. Method: This study included 581 children and adolescents aged 4 - 19 years who were suspected of having tuberculosis, were latently infected with Mycobacterium tuberculosis, and had received at least one dose of BCG vaccine between April 17, 2019, and February 24, 2021. The study evaluated the TST results of 106 patients who had a positive Quantiferon test and were suspected of having tuberculosis. Results: The study included 581 patients aged between 4 and 19 years. Of these, 106 patients tested positive for the Quantiferon test, while 19 were indeterminate and 456 were negative. The Quantiferon test positivity rate was 18.24%. Among the 106 QFT-Plus-positive cases, 23 patients also tested positive for TST. The difference in distribution was found to be statistically significant. Conclusion: The QFT-Plus test is considered an alternative to TST and other microbiological diagnostic methods for early tuberculosis diagnosis, particularly in children and adolescents.

关键词： Interferon Gamma Release Assay Children Tuberculin Test Children Latent Tuberculosis

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Simultaneous removal of 1,2-dichlorobenzene and furan over Mn-ce-Fe oxide catalyst:Catalytic activity and product analysis

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Journal of Rare Earths 2024年第5期42卷 972-979,I0006页

作者： Juan Qiu Minghui Tang Yaqi Peng Xuanhao Guo Shengyong lu Jianhua Yan Taizhou Institute of Zhejiang University Taizhou 318000China State Key Laboratory for Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The Mn-ce-Fe mixed oxide(MCFe)was prepared by co-precipitation and the catalytic performance was tested by using 1,2-dichlorobenzene(1,2-DCB)and furan as model molecules of PCDD/F.The effect of O_(2)concentration,SO_(2) and NO on the catalytic activity was studied.At 270℃,the MCFe oxide catalyst presents significant simultaneous removal efficiency of 75.25%and 100%for 1,2-DCB and furan,respectively.Brunauer-Emmett-Teller(BET)method(BET),X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR),H_2-temperature programmed reduction(H_(2)-TPR),NH_(3)-temperature programmed desorption(NH_3-TPD)and O_(2)-TPD were used to characterize the catalysts before and after the reaction.Competition tests suggest that the oxidation behavior of furan occurred prior to that of 1,2-DCB.According to the intermediate products detected by gas chromatography-mass spectrometry(GC-MS),the by-products include chlorinated hydrocarbons,long-chain hydrocarbons,ketone,etc.Possible catalytic oxidation reaction paths are proposed.

关键词： 1 2-dichlorobenzene Furan Catalytic oxidation Product analysis Rare earths

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环渤海河流营养盐的向海输送及环境效应

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中国环境科学 2024年第1期44卷 178-192页

作者：孙策策刘军张爱军李梦露吴文涛臧家业冉祥滨自然资源部第一海洋研究所自然资源部海洋生态环境科学与技术重点实验室山东青岛266061 中国水产科学研究院黄海水产研究所农业农村部海洋渔业可持续发展重点实验室山东省渔业资源与生态环境重点实验室山东青岛266071 山东长岛近海渔业资源国家野外科学观测研究站山东烟台265800 崂山实验室海洋地质过程与环境功能实验室山东青岛266237 中国海洋大学海洋化学理论与工程技术教育部重点实验室山东青岛266100

对2017年枯水期、2019年丰水期、2020年丰水期和2021年丰水期环渤海24条主要入海河流溶解态无机营养盐向海输送的浓度、比值和通量进行了分析.结果表明:环渤海河流溶解无机氮(DIN)浓度在世界河流中处于较高水平,硝酸盐(NO_(3)^(-))为DI... 详细信息

对2017年枯水期、2019年丰水期、2020年丰水期和2021年丰水期环渤海24条主要入海河流溶解态无机营养盐向海输送的浓度、比值和通量进行了分析.结果表明:环渤海河流溶解无机氮(DIN)浓度在世界河流中处于较高水平,硝酸盐(NO_(3)^(-))为DIN的主要赋存形态,溶解硅(DSi)和溶解无机磷(DIP)浓度较低.环渤海河流每年向渤海输送约0.61Gmol氨盐(NH_(4)^(+))、0.24Gmol亚硝酸盐(NO_(2)^(-))、4.85Gmol NO_(3)^(-)、0.02Gmol DIP和3.27Gmol DSi.环渤海小河流在环渤海河流营养盐的向海输送中扮演着重要作用,尤其是DIP的输送可以占入海河流总通量的80%以上;小河流单位流域面积DIN、DIP和DSi输送通量均高于黄河.与世界河流相比,环渤海河流向海输送的营养盐比例失衡,具有高氮磷比、高硅磷比和低硅氮比的特点,磷限制显著.环渤海河流营养盐向海输送和结构失衡可能会进一步影响到渤海的初级生产和生态环境演变,值得深入研究.

关键词：环渤海河流营养盐营养盐结构通量渤海

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Utilizing dual-pathway energy transfer in upconversion nanoconjugates for reinforced photodynamic therapy

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Nano Research 2024年第4期17卷 2941-2948页

作者： Ruohao Zhang Yu lu Yifei Zhou Kehong Lv Xinyu Fu Jitong Gong Shuang Yao Xiaozhen Wang Jing Feng Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China College of Chemistry Jilin UniversityChangchun 130012China Department of Breast Surgery General Surgery Centerthe First Hospital of Jilin UniversityChangchun 130021China Department of Chemistry Tsinghua UniversityBeijing 100084China

Enhancing the therapeutic effect of existing treatments or developing new non-invasive treatments are important measures to achieve high-efficiency treatment of malignant tumors.Photodynamic therapy(PDT)is an emerging treatment modality,and the key for achieving high-efficiency PDT is to select light with strong tissue penetration depth and enhance the generation of reactive oxygen species(ROS).Although the upconversion nanoparticles(UCNPs)modified with the photosensitizers could achieve PDT with strong penetration depth under near-infrared light irradiation,the ROS generated by traditional single-pathway PDT is still insufficient.Herein,we developed a novel nanoconjugate(UCNP-ce6/AIEgen)for dual-pathway reinforced PDT,in which the UCNPs were co-modified with chlorin e6(ce6)and luminogen with aggregation-induced emission(AIEgen).Due to the presence of AIEgen,UCNP-ce6/AIEgen could avoid aggregation-caused luminescence quenching in biological water environments and convert upconversion luminescence(UCL)of UCNPs to ce6-activatable fluorescence.Therefore,under the irradiation of 808 nm laser,UCNP-ce6/AIEgen can not only undergo direct lanthanide-triplet energy transfer to activate ce6,but also convert the UCL of UCNPs to the light that can activate ce6 through Fӧrster resonance energy transfer to generate more ROS,thus promoting tumor cell apoptosis.This work broadens the applications of nanoconjugates of lanthanide-based inorganic materials and organic dyes,and provides a conception for reinforced PDT of tumors.

关键词： upconversion nanoparticle aggregation-induced emission direct lanthanide-triplet energy transfer Förster resonance energy transfer photodynamic therapy

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