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Experimental observation of the significant difference between surface and bulk Kondo processes in Kondo lattice YbCu_(2)Si_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 154-160页

作者： Yin-Zou Zhao Jiao-Jiao Song Qi-Yi Wu Hao Liu Chen Zhang bo Chen Hong-Yi Zhang Zhen-hua Chen Yao-bo huang Xue-Qing Ye Ya-hua Yuan Yu-Xia Duan Jun He Jian-Qiao Meng School of Physics Central South UniversityChangsha 410083China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China

Synchrotron-based angle-resolved photoemission spectroscopy was employed to investigate the temperature evolution of the Yb 4 f spectral for surface and bulk in the Kondo lattice YbCu_(2)Si_(2).Our study quantitatively distinguishes between the surface and bulk hybridization processes,revealing that the onset temperatures for both surface and bulk hybridization processes are significantly higher than the Kondo temperature.Additionally,we found that the effective surface Kondo temperature is much lower than that of the bulk.These findings offer valuable insights into the understanding of heavy fermion physics.

关键词： Kondo lattice angle-resolved photoemission spectroscopy electronic structure hybridization surface state

Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients

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World Journal of Gastroenterology 2024年第4期30卷 308-317页

作者： Hai-Bin Zhu bo Zhao Xiao-Ting Li Xiao-Yan Zhang Qian Yao Ying-Shi sun Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of RadiologyPeking University Cancer Hospital and InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of PathologyPeking University Cancer Hospital and InstituteBeijing 100142China

BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver resection.Up to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after resection.AIM To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to surgery.METHODS In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after chemotherapy.Various parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were measured.The parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node status.The reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation coefficient.RESULTS Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of 0.873.Furthermore,parameters from SEM showed substantial repeatability.CONCLUSION The dev

关键词： Colorectal cancer Individualized treatment Diffusion magnetic resonance imaging Intravoxel incoherent motion Liver

Diabetic retinopathy identification based on multi-sourcefree domain adaptation

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1193-1204页

作者： Guang-hua Zhang Guang-Ping Zhuo Zhao-Xia Zhang Bin sun Wei-hua Yang Shao-Chong Zhang School of Big Data Intelligent Diagnosis&Treatment Industry Taiyuan UniversityTaiyuan 030032Shanxi ProvinceChina Shanxi Key Laboratory of Intelligent Optimization Computing and Blockchain Technology Taiyuan Normal UniversityTaiyuan 030619Shanxi ProvinceChina Shanxi Eye Hospital Taiyuan 030002Shanxi ProvinceChina College of Computer Science and Technology Taiyuan Normal UniversityTaiyuan 030619Shanxi ProvinceChina Shenzhen Eye Institute Shenzhen Eye HospitalJinan UniversityShenzhen 518040Guangdong ProvinceChina

AIM:To address the challenges of data labeling difficulties,data privacy,and necessary large amount of labeled data for deep learning methods in diabetic retinopathy(DR)identification,the aim of this study is to develop a source-free domain adaptation(SFDA)method for efficient and effective DR identification from unlabeled data.METHODS:A multi-SFDA method was proposed for DR identification.This method integrates multiple source models,which are trained from the same source domain,to generate synthetic pseudo labels for the unlabeled target domain.Besides,a softmax-consistence minimization term is utilized to minimize the intra-class distances between the source and target domains and maximize the inter-class distances.Validation is performed using three color fundus photograph datasets(APTOS2019,DDR,and EyePACS).RESULTS:The proposed model was evaluated and provided promising results with respectively 0.8917 and 0.9795 F1-scores on referable and normal/abnormal DR identification tasks.It demonstrated effective DR identification through minimizing intra-class distances and maximizing inter-class distances between source and target domains.CONCLUSION:The multi-SFDA method provides an effective approach to overcome the challenges in DR identification.The method not only addresses difficulties in data labeling and privacy issues,but also reduces the need for large amounts of labeled data required by deep learning methods,making it a practical tool for early detection and preservation of vision in diabetic patients.

关键词： diabetic retinopathy multisource-free domain adaptation pseudo-label generation softmaxconsistence minimization

Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

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International Journal of Extreme Manufacturing 2024年第1期6卷 277-294页

作者： bo Yao Nan Kang Xiangyu Li Dou Li Mohamed EL Mansori Jing Chen Haiou Yang hua Tan Xin Lin State Key Laboratory of Solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et Metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic devices.The essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and microstructure.In this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)technologies.Themicrostructure evolution and phase selection of Nd-Fe-B magnets were then clarified in detail.The results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase selection.In terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is presented.For the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(both the VIM-casting and LDED-processed Nd-Fe-B deposits exhibited poor magnetic properties.In contrast,employing the high values of V(>10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B magnet.Additionally,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic characteristics.Consequently,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic performance,comparable to other additive manufacturing

关键词： laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

Heavy ion energy influence on multiple-cell upsets in small sensitive volumes:from standard to high energies

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Nuclear Science and Techniques 2024年第5期35卷 109-121页

作者： Yang Jiao Li-hua Mo Jin-Hu Yang Yu-Zhu Liu Ya-Nan Yin Liang Wang Qi-Yu Chen Xiao-Yu Yan Shi-Wei Zhao bo Li You-Mei sun Pei-Xiong Zhao Jie Liu Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China University of Chinese Academy of Science Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China China Electronics Technology Group Corporation No.58 Research Institute Wuxi 214000China Beijing Microelectronics Technology Institute Beijing 100084China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Science and Technology on Silicon Devices Chinese Academy of SciencesBeijing 100029China

The 28 nm process has a high cost-performance ratio and has gradually become the standard for the field of radiation-hardened devices.However,owing to the minimum physical gate length of only 35 nm,the physical area of a standard 6T SRAM unit is approximately 0.16μm^(2),resulting in a significant enhancement of multi-cell charge-sharing effects.Multiple-cell upsets(MCUs)have become the primary physical mechanism behind single-event upsets(SEUs)in advanced nanometer node devices.The range of ionization track effects increases with higher ion energies,and spacecraft in orbit primarily experience SEUs caused by high-energy ions.However,ground accelerator experiments have mainly obtained low-energy ion irradiation data.Therefore,the impact of ion energy on the SEU cross section,charge collection mechanisms,and MCU patterns and quantities in advanced nanometer devices remains unclear.In this study,based on the experimental platform of the Heavy Ion Research Facility in Lanzhou,low-and high-energy heavy-ion beams were used to study the SEUs of 28 nm SRAM devices.The influence of ion energy on the charge collection processes of small-sensitive-volume devices,MCU patterns,and upset cross sections was obtained,and the applicable range of the inverse cosine law was clarified.The findings of this study are an important guide for the accurate evaluation of SEUs in advanced nanometer devices and for the development of radiation-hardening techniques.

关键词： 28 nm static random access memory(SRAM) Energy effects Heavy ion Multiple-cell upset(MCU) Charge collection Inverse cosine law

Ru(II)-Catalyzed ortho C-H Allylation of N-Aryl-7-azaindoles with 2-Methylidene Cyclic Carbonate

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Chinese Journal of Chemistry 2024年第9期42卷 985-989页

作者： Jing Zhang Quan-Jian Luo Han-Chi Wang Jin-Heng Li bo sun State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology QingdaoShandong266042China State key Laboratory of Applied Organic Chemistry Lanzhou University LanzhouGansu 7300ooChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A Ru(II)-catalyzed ortho allylation reaction of N-aryl-7-azaindole with readily available 2-methylidene cyclic carbonate has been developed.This reaction is an effective pathway for synthesizing 7-azaindole derivatives with a wide scope of substrates and high yields.In addition,the method can be extended to the allylation of other heterocyclic compounds and several cyclic carbonates,highlighting the practicality of this strategy for synthesis.

关键词： Ru(II) Allylation N-Aryl-7-azaindoles Cyclic carbonates Heterocyclic compounds C-H activation

Regulating electrochemical performances of lithium battery by external physical field

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Rare Metals 2024年第6期43卷 2391-2417页

作者： Shi-Kang Wang Shuai Wu Yi-Cheng Song Hassanien Gomaa Cui-hua An Qi-bo Deng Ning Hu School of Mechanical Engineering School of Materials Science and EngineeringHebei University of Technology Shanghai Key Laboratory of Mechanics in Energy Engineering Department of Chemistry Faculty of ScienceAl-Azhar University Tianjin Key Laboratory of Power Transmission and Safety Technology for New Energy Vehicles State Key Laboratory of Reliability and Intelligence Electrical Equipment Key Laboratory of Advanced Intelligent Protective Equipment TechnologyMinistry of EducationHebei University of Technology

Lithium batteries have always played a key role in the field of new energy sources.However,non-controllable lithium dendrites and volume dilatation of metallic lithium in batteries with lithium metal as anodes have limited their development.Recently,a large number of studies have shown that the electrochemical performances of lithium batteries can be enhanced through the regulation of external physical fields.Especially,it significantly hinders the growth of lithium dendrites and promoting the reaction kinetics.This review summarizes recent innovations in the investigation of various physical fields of lithium batteries.The application of magnetic field in the synthesis of lithium battery electrode materials is introduced.The influence factors and regulation mechanism of various physical fields on the electrochemical performance of lithium batteries are reviewed emphatically.In addition,the current research status and existing challenges,along with future directions for the evolution of lithium batteries,are minutely discussed and prospected.New strategies for the further evolution of lithium batteries have also been provided.

关键词： Lithium battery External field assist Reaction kinetics Lithium dendrite

Enhanced direct gaseous CO_(2) fixation into higher bio-succinic acid production and selectivity

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Journal of Environmental Sciences 2024年第9期143卷 164-175页

作者： Ziyi Yang Wanling Wu Qing Zhao Irini Angelidaki Samuel Gyebi Arhin Dongliang hua Yuxiao Zhao Hangyu sun Guangqing Liu Wen Wang Biomass Energy and Environmental Engineering Research Center Beijing University of Chemical TechnologyBeijing 100029China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Chemical and Biochemical Environmental Engineering Technical University of DenmarkDK-2800Kgs LyngbyDenmark Energy Research Institute Qilu University of Technology(Shandong Academy of Sciences)Shandong Provincial Key Laboratory of Biomass Gasification TechnologyJinan 250014China

Utilizing CO_(2)for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling(CCR)with simultaneous production of a useful platform chemical.Actinobacillus succinogenes and Basfia succiniciproducens were selected and investigated as microbial catalysts.Firstly,the type and concentration of inorganic carbon concentration and glucose concentration were evaluated.6 g C/L MgCO_(3)and 24 g C/L glucose were found to be the optimal basic operational conditions,with succinic acid production and carbon yield of over 30 g/L and over 40%,respectively.Then,for maximum gaseous CO_(2)fixation,carbonate was replaced with CO_(2)at different ratios.The“less carbonate more CO_(2)”condition of the inorganic carbon source was set as carbonate:CO_(2)=1:9(based on the mass of carbon).This condition presented the highest availability of CO_(2)by well-balanced chemical reaction equilibrium and phase equilibrium,showing the best performance with regarding CO_(2)fixation(about 15 mg C/(L·hr)),with suppressed lactic acid accumulation.According to key enzymes analysis,the ratio of phosphoenolpyruvate carboxykinase to lactic dehydrogenase was enhanced at high ratios of gaseous CO_(2),which could promote glucose conversion through the succinic acid path.To further increase gaseous CO_(2)fixation and succinic acid production and selectivity,stepwise CO_(2)addition was evaluated.50%-65%increase in inorganic carbon utilization was obtained coupled with 20%-30%increase in succinic acid selectivity.This was due to the promotion of the succinic acid branch of the glucose metabolism,while suppressing the pyruvate branch,along with the inhibition on the conversion from glucose to lactic acid.

关键词： Succinic acid CO_(2) fixation Actinobacillus succinogenes Basfia succiniciproducens Lactic acid

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang Li Yu Liu Xiao-Xiao Ling Li-Guang Wu Li Yang Lan Yang bo Yang Yong-Gang Zhao Xian-hua Li State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo