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Rare Metals 2023年第4期42卷 1306-1315页

作者： De-Zhi Chen Qi Wang Rui-Run Chen Shu Wang yan-Qing su Heng-Zhi Fu National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin150001China

Five Nb-16Si-20Ti-xMgO alloys(x=0,0.1,0.5,1.0 and 3.0)were prepared via arc melting in this study,and the effect of MgO addition on their phase composition,microstructure evolution,and mechanical properties was *** results demonstrated that MgO reacted with the Nb-Si-Ti alloy while Mg atoms replaced Nb atoms in the Nbss *** hypoeutectic alloy was transformed into a hypereutectic alloy upon the addition of 3.0 at%MgO,and the Nb_(3)Si phases decomposed into a fine Nbss/α-Nb5Si3 eutectic *** highest fracture toughness was achieved for the Nb-16Si-20Ti-3MgO alloy,with an ambient fracture toughness value of 9.4 MPa·m^(-1/2)due to its largest Nbss phase content and optimal Nbss/α-Nb_(5)Si_(3)eutectic ***,the alloy compressive strength increased with MgO *** compressive strength of the Nb-16Si-20Ti-3MgO alloy was 2624.1 MPa,26.0%higher than that of Nb-16Si-20Ti,due to the formation of a solid solution of Mg atoms in the Nbss phase and reinforcement of a small amount of the Ti_(2)O ***,an increase in the content of the Nbss/α-Nb_(5)Si_(3)eutectic structure increased both the alloy strength and fracture strain.

关键词： Niobium silicon alloy Magnesium oxide Eutectic structure Fracture toughness

ZIP4 inhibits Ephrin-B1 ubiquitination,activating Wnt5A/JNK/ZEB1 to promote liver cancer metastasis

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Genes & Diseases 2024年第6期11卷 1-4页

作者： Haijun Guo Renyi su Xinfeng Lu Hui Zhang Xuy.ng Wei Xiao Xu Department of Hepatobiliary and Pancreatic surgery Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhouZhejiang 310006China Zhejiang University School of Medicine HangzhouZhejiang 310058China The Fourth School of Clinical Medicine Zhejiang Chinese Medicine UniversityHangzhouZhejiang 310053China School of Clinical Medicine Hangzhou Medical CollegeHangzhouZhejiang 310014China

Hepatocellular carcinoma(HCC),a highly malignant tumor,faces a major challenge with its high post-hepatectomy recurrence impacting patient *** and preventive strategies remain to be ***-/lrt-like protein 4(ZIP4,also called SLC39A4/solute carrier family 39 member 4)belongs to the zinc transporter ZiP superfamily of which the members play an important role in maintaining zinc steady state,and its high expression in various tumors is associated with the prognosis of cancer patients.

关键词： ZEB1 metastasis cancer

Turning weak into strong: on the CTAB-induced active surface growth

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Science China Chemistry 2022年第7期65卷 1299-1305页

作者： y.nglong Zheng Jianpeng Zong Ting Xiang Quan Ren Dongmeng su yuhua Feng yawen Wang Hongyu Chen Institute of Advanced Synthesis(IAS) School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Centre for Advanced MaterialsNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310023China

Discovering new methods and principles in the inequivalent growth of equivalent facets is of great significance for going beyond symmetrical nanocrystals and for out-of-box exploration. In this work, we demonstrate that a middle ground exists between the traditional weak ligands and the strong ligands with unusual growth modes. By modify.ng the seed concentration during the growth of pentagonal Au nanorods, the typical weak ligand cetyltrimethylammonium bromide(CTAB) is made strong, leading to notches of restricted growth and even the active surface growth mode. In-depth investigation in the link between growth kinetics and ligand packing reveals the principle of their interplay —— that the on-off dynamics of the ligands only allows for a certain limit of materials deposition rate. Beyond this limit, the growth materials build up and are then diverted elsewhere, leading to inequivalent growth. The fact that a freshly grown surface has few ligands promotes the active surface growth, focusing the growth materials onto a few sites. We believe that the knowhow of interfering ligand packing via growth kinetics would offer a powerful tool of synthetic control, where the facet-and curvature-dependent ligand packing is expected to be useful synthetic handles.

关键词： facet control ligand packing active surface growth Au deposition ligand dissociation

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Mineralogical characterization of copper sulfide tailings using automated mineral liberation analysis: A case study of the Chambishi Copper Mine tailings

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 944-955页

作者： Xiao-liang Zhang Jue Kou Chun-bao sun Rui-y.ng Zhang Min su Shuo-fu Li School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Non-ferrous Corporation Africa Mining Public Limited Company Kitwe 22592Zambia

As ore grades constantly decline,more copper tailings,which still contain a considerable amount of unrecovered copper,are expected to be produced as a byproduct of froth *** research reveals the occurrence mechanism of copper minerals in typical copper sulfide tailings using quantitative mineral liberation analysis(MLA)integrated with scanning electron microscopy–energy dispersive spectroscopy(SEM–EDS).A comprehensive mineralogical characterization was carried out,and the results showed that almost all copper minerals were highly disseminated within coarse gangue particles,except for 9.2wt%chalcopyrite that occurred in the 160–180μm size *** predominant copper-bearing mineral was chalcopyrite,which was closely intergrown with orthoclase and muscovite rather than *** flotation tailings sample still contained 3.28wt%liberated chalcopyrite and 3.13wt%liberated bornite because of their extremely fine *** SEM–EDS analysis further demonstrated that copper minerals mainly occurred as fine dispersed and fully enclosed structures in gangue *** information obtained from this research could offer useful references for recovering residual copper from flotation tailings.

关键词： copper tailings chalcopyrite mineral liberation analysis particle size boundary breakage

Modeling and prediction of tribological properties of copper/aluminum-graphite self-lubricating composites using machine learning algorithms

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Friction 2024年第6期12卷 1322-1340页

作者： Huifeng NIng Faqiang CHEN yunfeng su Hongbin LI Hengzhong FAN Junjie SOng y.ngsheng ZHAng Litian HU School of Electrical and Mechanical Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The tribological properties of self-lubricating composites are influenced by many variables and complex ***-driven methods,including machine learning(ML)algorithms,can yield a better comprehensive understanding of complex problems under the influence of multiple parameters,typically for how tribological performances and material properties *** of friction coefficients and wear rates of copper/aluminum-graphite(Cu/Al-graphite)self-lubricating composites with their inherent material properties(composition,lubricant content,particle size,processing process,and interfacial bonding strength)and the variables related to the testing method(normal load,sliding speed,and sliding distance)were analyzed using traditional approaches,followed by modeling and prediction of tribological properties through five different ML algorithms,namely support vector machine(SVM),K-Nearest neighbor(KNN),random forest(RF),eXtreme gradient boosting(XGBoost),and least-squares boosting(LSBoost),based on the tribology experimental *** demonstrated that ML models could satisfactorily predict friction coefficient and wear rate from the material properties and testing method variables ***,the LSBoost model based on the integrated learning algorithm presented the best prediction performance for friction coefficients and wear rates,with R^(2) of 0.9219 and 0.9243,*** importance analysis also revealed that the content of graphite and the hardness of the matrix have the greatest influence on the friction coefficients,and the normal load,the content of graphite,and the hardness of the matrix influence the wear rates the most.

关键词： self-lubricating composites machine learning(ML) tribological properties prediction

Neuroimaging studies in major depressive disorder with suicidal ideation or behaviour among Chinese patients:implications for neural mechanisms and imaging signatures

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General Psychiatry 2024年第5期37卷 511-521页

作者： yun-Ai su Chong ye Qin Xin Tianmei Si Peking University Sixth Hospital Peking University Institute of Mental HealthNHC Key Laboratory of Mental Health(Peking University)National Clinical Research Center for Mental Disorders(Peking University Sixth Hospital)BeijingChina Xi'an Janssen Pharmaceutical Ltd BeijingChina

Major depressive disorder(MDD)with suicidal ideation or behaviour(MDSI)is associated with an increased risk of future *** timely identification of suicide risk in patients with MDD and the subsequent implementation of interventions are crucially important to reduce their suffering and save ***,the early diagnosis of MDSI remains challenging across the world,as no objective diagnostic method is currently *** China,the challenge is greater due to the social stigma associated with mental health problems,leading many patients to avoid reporting their suicidal ***,the neural mechanisms underly.ng MDSl are stll unclear,which may hamper the development of effective *** thus conducted this narrative review to summarise the existing neuroimaging studies of MDSI in Chinese patients,including those involving structural magnetic resonance imaging(MRI),functional MRl,neuronal electrophysiological source imaging of the brain dynamics with electroencephalography and *** synthesising the current research efforts in neuroimaging studies of Chinese patients with MDSl,we identified potential objective neuroimaging biomarkers,which may aid in the early identification of patients with MDSI who are at high suicide-related *** findings also offer insights into the complex neural mechanisms underly.ng MDSI and suggest promising therapeutic ***,we propose future directions to discover novel imaging signatures,improve patient care,as well as help psychiatrists and clinical investigators plan their future research.

关键词： patients neural signature

Bright and pure single-photons from quantum dots in micropillar cavities under up-converted excitation

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Science Bulletin 2018年第12期63卷 739-742页

作者： Rongling su Shunfa Liu yuming Wei y.ng yu Jin Liu Siyuan yu Xuehua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySchool of PhysicsSun Yat-sen University Photonics Group Merchant Venturers School of EngineeringUniversity of Bristol

Self-assembled semiconductor quantum dots(QDs)are potentially scalable candidates for solid-state single-photon emitters which deterministically generate one single-photon per *** on-demand single-photon sources serve as one of the key elements in modern photonic quantum technologies[1].Until very recently,near-optimal QD single-photon sources with simultaneous high degree of brightness,single-photon purity and indistin-

关键词：光子量点半导体候选人可伸缩

Ultrahigh pyroelectric effect and energy harvesting density of Pb(Lu_(1/2)Nb_(1/2))O_(3)-PbTiO_(3) crystals induced by FE-AFE phase transition

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Journal of Rare Earths 2021年第12期39卷 1567-1573,I0005页

作者： Lingfei Lv Manman Liu y.ng Liu Zujian Wang Rongbing su Xiaoming y.ng Chao He Xifa Long College of Chemistry Fuzhou UniversityFuzhou 350116China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Large pyroelectric and energy harvesting properties have been attracting increasing attentions due to the practical applications in infrared detectors and energy harvesting ***(FE-AFE)phase transitions are usually accompanied by a sharp drop in polarization,which will lead to excellent pyroelectric properties and energy harvesting ***,FE-AFE phase boundary design is an effective strategy to develop new pyroelectric *** this paper,Pb(Lu_(1/2)Nb_(1/2))O_(3)-PbTiO_(3) (PLN-PT)single crystals with FE-AFE phase transitions were obtained by molten salt growth *** temperature-induced FE-AFE phase transition was verified by temperaturedependent macrodomain structure,DSC curves and dielectric ***,PLN-PT crystals display excellent peak pyroelectric coefficient(~6.8μC/(cm^(2)·K)with a maximum depolarization temperature of 118℃.Meanwhile,the pyroelectric energy harvesting density is as high as 2.62 J/cm3,which is much higher than other pyroelectric *** results reveal that the PLN-PT crystal is a promising candidate for infrared detectors and energy harvesting devices.

关键词： Rare earth crystals Phase transition Pyroelectricity Energy harvesting density

Determination of minimum overburden depth for underwater shield tunnel in sands:Comparison between circular and rectangular tunnels

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1671-1686页

作者： Weixin sun Fucheng Han Hanlong Liu Wengang Zhang yanmei Zhang Weijia su Songlin Liu School of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing400045China School of Aerospace Engineering Chongqing UniversityChongqing400045China

With the development of global urbanization,the utilization of underground space is more critical and attractive for civil *** shapes of shield tunnels have been gradually proposed to cope with different geological conditions and service purposes of underground ***,reducing the burial depth of shield tunnel is conducive to construction and cost ***,extremely small overburden depth cannot provide sufficient uplift resistance to maintain the stability and serviceability of the *** this end,this paper firstly reviewed the status of deriving the minimum sand over-burden depth of circular shield tunnel using mechanical equilibrium(ME)*** revealed that the estimated depth is rather ***,the uplift resistance mechanism of both circular and rectangular tunnels was deduced theoretically and verified with the model *** theoretical uplift resistance is consistent with the experimental values,indicating the feasibility of the proposed ***,the determination of the minimum soil overburden depth of rectangular shield tunnel under various working conditions was presented through integrated ME method,which can provide more reasonable estimations of suggested tunnel burial depth for practical ***,optimizations were made for calculating the uplift resistance,and the soil thickness providing uplift resistance is suggested to be adjusted according to the testing *** results can provide reference for the design and construction of various shapes of shield tunnels in urban underground space exploitation.

关键词： Minimum overburden depth Uplift resistance mechanism Shield tunnel shape Tunnel anti-floating

Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China

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Asian Herpetological Research 2024年第3期15卷 140-151页

作者： Chaobo FEng Tuo SHEN Lang MU Jing LIU Shize LI yixin DIAO Haijun su Forestry College of Guizhou University Guiyang 550025GuizhouChina Guizhou Wildlife Protection Association Guiyang 550025GuizhouChina Department of Resources and Environment Moutai InstituteRenhuai 564500GuizhouChina Research Center for Biodiversity and Nature Conservation Guizhou UniversityGuiyang 550025GuizhouChina Guizhou Karst Environmental Ecosystems Observation and Research Station Ministry of EducationGuiyang 550025GuizhouChina

In anurans,advertisement calls(ACs)are an essential form of intraspecific *** study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental *** are simple calls of ***,and apparent differences were observed in the ACs among different geographical populations of *** Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and ***,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with *** variations in ACs between different geographical populations of *** may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection.

关键词： anuran bioacoustics environmental factors geographical divergence