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Evidence for the lower Continental Crustal Origin of the Xihuashan Granite

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Acta Geologica Sinica(English Edition) 1986年第3期60卷 47-64+112-114页

作者： l.le bel G.Giuliani GIS BRGM-CNRS of France

The Xihuashan granite is typically representative of the tungsten-bearing granites widespread in theNanling area of South China. It was considered in the past to have been formed by partial melting of the upper continental crust, with its source rocks most probably of the Sinian or Cambrian. However, detailed REE analyses, studies of the Rb-Sr isotopic system and melting experiments of metasedimentary rocks all argue against this idea. Moreover, stable isotopic data also indicate a deep source origin for S, C, H and O. The authors thus propose a genetic concept of the lower continental crustal source of the Xihuashan granite, and point out further that tungsten deposits related to this kind of granite are linked in some way to deep-seated structure and concentrated along NNE-NE- and ENE-striking major deep fault belts above the transitional zone between mantle uplift and mantle depression.

关键词： Evidence for the lower Continental Crustal Origin of the Xihuashan Granite

Quantification of corneal neovascularization after ex vivo limbal epithelial stem cell therapy

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International journal of Ophthalmology(English edition) 2014年第6期7卷 988-995页

作者： Adriano Guarnieri javier Moreno-Monta?és belén Alfonso-Bartolozzi Alfonso l.Sabater María García-Guzmán Enrique j.Andreu Felipe Prosper Department of Ophthalmology Clínica Universidad de Navarra Department of Cell Therapy Clínica Universidad de Navarra

AIM: To assess cultured limbal epithelial stem cell transplantation in patients with limbal stem cell deficiency by analyzing and quantifying corneal ***: This retrospective, interventional case series included eight eyes with total limbal stem cell deficiency. Ex vivo limbal epithelial stem cells were cultured on human amniotic membrane using an animalfree culture method. The clinical parameters of limbal stem cell deficiency, impression cytology, and quantification of corneal neovascularization were evaluated before and after cultured limbal stem cell transplantation. The area of corneal neovascularization,vessel caliber(VC), and invasive area(IA) were analyzed before and after stem cell transplantation by image analysis software. Best-corrected visual acuity(BCVA),epithelial transparency, and impression cytology were also ***: One year after surgery, successful cases showed a reduction(improvement) of all three parameters of corneal neovascularization [neovascular area(NA), VC, IA], while failed cases did not. NA decreased a mean of 32.31%(P =0.035), invasion area29.37%(P =0.018) and VC 14.29%(P =0.072). BCVA improved in all eyes(mean follow-up, 76 ±21mo).Epithelial transparency improved significantly from 2.00 ±0.93 to 0.88±1.25(P =0.014). Impression cytology showed that three cases failed after limbal epithelial stem cell therapy before 1y of ***: This method of analyzing andmonitoring surface vessels is useful for evaluating the epithelial status during follow-up, as successful cases showed a bigger reduction in corneal neovascularization parameters than failed cases. Using this method,successful cases could be differentiated from failed cases.

关键词： limbal stem cell corneal neovascularization stem cell therapy impression cytology limbal stem cell deficiency

In situ neutron diffraction unravels deformation mechanisms of a strong and ductile Fe Cr Ni medium entropy alloy

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journal of Materials Science & Technology 2022年第21期116卷 103-120页

作者： l.Tang F.Q.jiang j.S.Wróbel B.liu S.Kabra R.X.Duan j.H.luan Z.B.jiao M.M.Attallah D.Nguyen-Manh B.Cai School of Metallurgy and Materials University of BirminghamB152TTUnited Kingdom Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Faculty of Materials Science and Engineering Warsaw University of Technologyul.Wołoska 141Warsaw 02-507Poland State Key laboratory for Powder Metallurgy Central South UniversityChangsha 410083China Rutherford Appleton laboratory ISIS FacilityDidcot OX110QXUnited Kingdom Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomHong KongChina CCFE United Kingdom Atomic Energy AuthorityAbingdonOxfordshire OX143DBUnited Kingdom

We investigated the mechanical and microstructural responses of a high-strength equal-molar medium entropy FeCrNi alloy at 293 and 15 K by in situ neutron diffraction *** 293 K,the alloy had a very high yield strength of 651±12 MPa,with a total elongation of 48%±5%.At 15 K,the yield strength increased to 1092±22 MPa,but the total elongation dropped to 18%±1%.Via analyzing the neutron diffraction data,we determined the lattice strain evolution,single-crystal elastic constants,stacking fault probability,and estimated stacking fault energy of the alloy at both temperatures,which are the critical parameters to feed into and compare against our first-principles calculations and dislocation-based slip system *** density functional theory calculations show that the alloy tends to form shortrange order at room ***,atom probe tomography and atomic-resolution transmission electron microscopy did not clearly identify the short-range ***,at 293 K,experimental measured single-crystal elastic constants did not agree with those determined by first-principles calculations with short-range order but agreed well with the values from the calculation with the disordered configuration at 2000 *** suggests that the alloy is at a metastable state resulted from the fabrication *** view of the high yield strength of the alloy,we calculated the strengthening contribution to the yield strength from grain boundaries,dislocations,and lattice *** lattice distortion contribution was based on the Varenne-luque-Curtine strengthening theory for multi-component alloys,which was found to be 316 MPa at 293 K and increased to 629 MPa at 15 K,making a significant contribution to the high yield *** plastic deformation,dislocation movement and multiplication were found to be the dominant hardening mechanism at both temperatures,whereas twinning and phase transformation were not *** is mainly due to the high stack

关键词： Medium entropy alloy Multi-component alloy Cryogenic temperature Neutron diffraction

How the interplay among the tumor microenvironment and the gut microbiota influences the stemness of colorectal cancer cells

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World journal of Stem Cells 2023年第5期15卷 281-301页

作者： María belén Novoa Díaz Pedro Carriere Claudia Gentili Departamento de Biología Bioquímica y FarmaciaUniversidad Nacional del SurBahía Blanca 8000Buenos AiresArgentina Instituto de Ciencias Biológicas y Biomédicas del Sur Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)-Universidad Nacional del Sur(UNS)Bahía Blanca 8000Buenos AiresArgentina

Colorectal cancer(CRC)remains the third most prevalent cancer disease and involves a multi-step process in which intestinal cells acquire malignant *** is well established that the appearance of distal metastasis in CRC patients is the cause of a poor prognosis and treatment ***,in the last decades,CRC aggressiveness and progression have been attributed to a specific cell population called CRC stem cells(CCSC)with features like tumor initiation capacity,self-renewal capacity,and acquired multidrug *** data highlight the concept of this cell subtype as a plastic entity that has a dynamic status and can be originated from different types of cells through genetic and epigenetic *** alterations are modulated by complex and dynamic crosstalk with environmental factors by paracrine *** is known that in the tumor niche,different cell types,structures,and biomolecules coexist and interact with cancer cells favoring cancer growth and ***,these components constitute the tumor microenvironment(TME).Most recently,researchers have also deepened the influence of the complex variety of microorganisms that inhabit the intestinal mucosa,collectively known as gut microbiota,on *** TME and microorganisms participate in inflammatory processes that can drive the initiation and evolution of *** in the last decade,crucial advances have been made concerning to the synergistic interaction among the TME and gut microorganisms that condition the identity of CCSC,the data exposed in this review could provide valuable insights into the biology of CRC and the development of new targeted therapies.

关键词： Colorectal cancer Colorectal cancer stem cells Tumor microenvironment factors Tumor stroma Gut microbiota Cancer progression

Shear strength behavior of geotextile/geomembrane interfaces

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journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 638-645页

作者： belén M.Bacas jorge Caizal Heinz Konietzky Terrasolum S.l.Geotechnical Engineering Technology Development Center of University of Cantabria(CDTUC) School of Civil Engineering University of Cantabria Geotechnical Institute TU Bergakademie Freiberg

This paper aims to study the shear interaction mechanism of one of the critical geosynthetic interfaces,the geotextile/geomembrane, typically used for lined containment facilities such as landfills. A largedirect shear machine is used to carry out 90 geosynthetic interface tests. The test results show a strainsoftening behavior with a very small dilatancy （〈0.5 mm） and nonlinear failure envelopes at a normalstress range of 25e450 kPa. The influences of the micro-level structure of these geosynthetics on themacro-level interface shear behavior are discussed in detail. This study has generated several practicalrecommendations to help professionals to choose what materials are more adequate. From the threegeotextiles tested, the thermally bonded monofilament exhibits the best interface shear strength underhigh normal stress. For low normal stress, however, needle-punched monofilaments are *** the regular textured geomembranes tested, the space between the asperities is an important *** closer these asperities are, the better the result achieves. For the irregular textured geomembranestested, the nonwoven geotextiles made of monofilaments produce the largest interface shear strength.

关键词： Geotextiles Geomembranes landfills Fiber length Roughness Shear strength Friction angle

Safety assessment methodology for a German high-level waste repository in clay formations

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journal of Rock Mechanics and Geotechnical Engineering 2017年第5期9卷 856-876页

作者： M.jobmann A.Bebiolka V.Burlaka P.Herold S.jahn A.lommerzheim j.MaBmann A.Meleshyn S.Mrugalla K.Reinhold A.Rübel l.Stark G.Ziefle DBE TECHNOlOGY GmbH Eschenstra 55 Peine D-31224 Germany Bundesanstalt für Geowissenschaften und Rohstoffe (BGR) Stilleweg 2 Hannover D-30655 Germany Gesellschaft fur Anlagen- und Reaktorsicherheit (GRS) gGmbH Theodor-Heuss-Stra 4 Braunschweig D-38122 Germany

In the ANSICHT project that was jointly carried out by DBE TECHNOlOGY Gmb H,BGR,and GRS g Gmb H,two generic geological site models were used to develop a first draft of a methodology to demonstrate the safety of a high-level waste(HlW) repository in argillaceous formations in Germany,taking into account the regulatory *** main results of the project are characterised by the developed repository concepts adapted to the geological *** specific quantifications of the integrity criteria and their exemplary application with calculational proofs were used to demonstrate the integrity of the host *** development of site-specific FEP(features,events,and processes) cataloges provided a complete system description for evaluation of the repository *** developed work flow of the demonstration concept illustrated the complete sequence of the safety proof in a transparent *** shows that various steps have to be performed,possibly iteratively,to provide a successful safety *** results form a useful tool in the pending search for a HlW repository site,especially when providing a basis for comparing safety analyses of different sites in Germany.

关键词： Clay Radioactive waste Safety demonstration method Barrier integrity FEP(features events and processes) cataloge

Evolution of phase stresses in Al/SiCp composite during thermal cycling and compression test studied using diffraction and self-consistent models

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journal of Materials Science & Technology 2020年第1期36卷 176-189页

作者： Przemyslaw Kot Andrzej Baczmański Elzbietaa Gadalińska Sebastian Wroński Marcin Wroński Miroslaw Wróbel Gizo Bokuchava Christian Scheffzük Krzysztof Wierzbanowski AGH University of Science and Technology Faculty of Physics and Applied Computer Scienceal.Mickiewicza 3030-059 Krakow.Poland Institute of Aviation Materials&Structures Research Centeral.Krakowska 110/11402-256 WarsawPoland AGH University of Science and Technology Faculty of Metals Engineering and Industrial Computer Scienceal.Mickiewicza 3030-059 KrakowPoland joint Institute for Nuclear Research Frank Laboratory of Neutron PhysicsJoliot-Curie 6141980 DubnaRussia Karlsruhe Institute of Technology Institute of Applied GeosciencesAdenauerring 20b76131 KarlsruheGermany

In this work,the evolutions of stresses in both phases of the Al/SiCp composite subjected to thermal cycling during in situ compression test were measured using Time of Flight neutron *** was confirmed that inter-phase stresses in the studied composite can be caused by differences in the coefficient of thermal expansion for the reinforcement and matrix,leading to a different variation of phase volumes during sample heating or *** results of the diffraction experiment during thermal cycling were well predicted by the Thermo-Mechanical Self-Consistent *** experimental study of elastic-plastic deformation was carried out in situ on a unique diffractometer EPSIlON-MDS(jINR in Dubna,Russia)with nine detector banks measuring interplanar spacings simultaneously in 9 orientations of scattering *** the first time,the performed analysis of experimental data allowed to study the evolution of full stress tensor in both phases of the composite and to consider the decomposition of this tensor into deviatoric and hydrostatic *** was found that the novel Developed Thermo-Mechanical SelfConsistent model correctly predicted stress evolution during compressive loading,taking into account the relaxation of thermal origin hydrostatic *** comparison of this model with experimental data at the macroscopic level and the level of phases showed that strengthening of the Al/SiCp composite is caused by stress transfer from the plastically deformed A12124 matrix to the elastic SiCp reinforcement,while thermal stresses relaxation does not significantly affect the overall composite properties.

关键词： Stress relaxation Strengthening mechanism Plastic deformation Multiscale model Metal matrix composites Neutron diffraction

Study of the effect of magnetic fields on static degradation of Fe and Fe-12Mn-1.2C in balanced salts modified Hanks’solution

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Bioactive Materials 2024年第10期40卷 524-540页

作者： Irene lim′on Marta Multigner Carlo Paternoster Marcela lieblich bel′en Torres Diego Mantovani joaquín Rams Dpto.de Matem′atica Aplicad1 Ciencia e Ingeniería de Materiales y Tecnología Electr′onic1ESCETUniversidad Rey Juan CarlosTulip′an S/n28933M′ostolesMadridSpain laboratory for Biomaterials and Bioengineering Dept of Min-Met-Materials EngineeringLaval University&University Hospital Research CenterQuebec CityCanada Centro Nacional de Investigaciones Metalúrgicas(CENIM-CSIC) 28040MadridSpain

Iron and its alloys are attractive as biodegradable materials because of their low toxicity and suitable mechanical properties;however,they generally have a slow degradation *** that corrosion is an electrochemical phenomenon where an exchange of electrons takes place,the application of magnetic fields from outside the body may accelerate the degradation of a ferrous temporary *** the present study,we have investigated the effect of alternating and direct low magnetic field(H=6.5 kA/m)on the corrosion process of pure iron(Fe)and an iron-manganese alloy(FeMnC)in modified Hanks’solution.A 14-day static immersion test was performed on the *** corrosion rate was assessed by mass and cross-sectional loss measurements,scanning electron microscopy,X-ray diffractometry,Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy before and after *** results show that the presence of magnetic fields significantly accelerates the degradation rate of both materials,with the corrosion rate being twice as high in the case of Fe and almost three times as high for *** addition,a homogenous degradation layer is formed over the entire surface and the chemical composition of the degradation products is the same regardless of the presence of a magnetic field.

关键词： Biometals Biodegradable iron alloy Corrosion Magnetic fields Biodegradable implant Magnetohydrodynamics

Enhanced activity and durability of FeCoCrMoCBY nanoglass in acidic hydrogen evolution reaction

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journal of Materials Science & Technology 2024年第3期170卷 212-220页

作者： Mengyang Yan Shuangqin Chen Shangshu Wu Xuechun Zhou Shu Fu Di Wang Christian Kübel Horst Hahn Si lan Tao Feng Herbert Gleiter Institute of Nanoscience School of Material Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Institute of Nanotechnology Karlsruhe Institute of TechnologyKarlsruhe 76021Germany

In the present work,a multi-element nanoglass(m-NG)of FeCoCrMoCBY is obtained first time by the laser ablation combined with inert gas condensation(laser-IGC)*** with the conventional rapid-quenched metallic glass(MG)with identical composition,the Fe-based m-NG demonstrates a superior performance as a self-supported electrocatalyst for hydrogen evolution reaction(HER)in acidic *** enhanced HER activity of m-NG is proposed to be closely related to its high en-ergy states,which is originated from the unique inhomogeneous nanostructures with a high density of low-coordinated ***,the Fe-based m-NG exhibits an outstanding comprehensive catalytic performance even beyond the commercial Pt/C catalyst in long-term test due to its self-optimization *** work not only opens the way to the preparation of m-NGs by the novel laser-IGC technique,but also makes a great contribution to developing low-cost,high-efficient,and super-durable HER electrocat-alysts in acidic environment.

关键词： Nanoglass Inert gas condensations High energy states Hydrogen evolution reactions