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Refractory high-entropy alloys:A focused review of preparation methods and properties

Journal of Materials Science & Technology 2023年第11期142卷 196-215页

作者： Wei Xiong Amy X.Y.Guo Shuai Zhan Chain-Tsuan Liu Shan cecilia Cao Materials Genome Institute Shanghai UniversityShanghai 200444China Hong Kong Institute of Advanced Study City University of Hong KongKowloonHong KongChina

In recent years,high-entropy alloys(HEAs)have become prominent metallic materials due to their unique design strategies and excellent mechanical *** HEAs-inherent high-entropy,lattice-distortion,sluggish-diffusion,and cocktail effects make HEAs maintain high strength,oxidation resistance,corrosion resistance,wear resistance,and other excellent comprehensive properties,showing stronger competitiveness relative to traditional *** high-entropy alloys(RHEAs)are considered as a new kind of high-temperature materials with great application prospects due to their excellent mechanical properties and have the potential to replace nickel-based superalloy as the next generation of high-temperature *** reviewed the research status and preparation methods of RHEAs in recent years,including the metallurgical smelting,powder metallurgy,magnetron sputtering,and additive manufacturing *** microstructure and phase-transformation process of RHEAs were *** mechan-ical properties and main strengthening and toughening mechanisms of RHEAs,such as solid-solution strengthening,precipitation strengthening,and the transformation-induced plasticity(TRIP),were discussed,and the deformation mechanism of RHEAs was *** properties of RHEAs,including high strength,oxidation resistance,corrosion and wear resistance were *** will meet the huge market demand in the engineering materials field,but there are still many challenges,such as the tradeoff between high strength and high ductility,structural design,and performance optimization of RHEAs with brittle BCC *** believe that this combination of knowledge may shape the future of RHEAs and break through the mutually exclusive conundrum of high strength and high toughness for RHEAs.

关键词： Refractory high-entropy alloy Preparation technology Phase transformation Mechanical properties Strengthening and toughening mechanisms Deformation mechanisms

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Effect of rare-earth oxides on properties of silicon nitride obtained by normal sintering and sinter-HIP

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Journal of Rare Earths 2012年第11期30卷 1177-1183页

作者： cecilia C.Guedes-Silva Flávio Machado de Souza Carvalho José Carlos Bressiani Nuclear and Energy Research Institute-IPEN/CNEN Geoscience Institute-IGC/USP

This paper presented the microstructure, mechanical properties and oxidation behavior of silicon nitride obtained by both conventional sintering and sintering followed by hot isostatic pressing （HIP）. Silicon nitride with additives such as 5 wt.% Al2O3 and 5 wt.% Ln203 （Ln= La, La concentrate, Gd or La＋Gd） were studied. The results revealed that Gd203 additions increased the formation of elongated grains of β-Si3N4, the fracture toughness and oxidation resistance. La2O3 additions led to higher densification and hardness values, while addition of La2O3 concentrate promoted the formation of materials with intermediate properties, compared to the other studied compositions. Hot isostatic pressing increased the hardness but decreased the fracture toughness of the material, mainly because it allowed residual pores to close and also reduced the average aspect ratio of β-Si3N4 grains.

关键词： rare earths silicon nitride properties normal sintering sinter-HIP

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Weather or weathering?Growth of Nothofagus dombeyi on volcanic soils differing in nitrogen and phosphorus concentrations

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Journal of Plant Ecology 2016年第5期9卷 596-607页

作者： Christoph Walter cecilia A.Pérez Frank M.Thomas Faculty of Regional and Environmental Sciences GeobotanyUniversity of TrierBehringstraße 2154296 TrierGermany Departamento de Ecología de Ecosistemas Instituto de Ecología y Biodiversidad(IEB)Alameda 340SantiagoChile

Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem increment of Nothofagus dombeyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central *** We took soil samples and tree increment cores from five proximate sites(1000-1300 m a.s.l.)that are located in the volcanic region of the Conguillío National Park and differ in the age of the substrate(Miocene—3500 years B.P.)and in its concentrations of nitrogen(N)and phosphorus(P).The soil samples were also analysed on their concentrations of other plant mineral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem basal area increment(BAI)were related to climate *** selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determined and related to growth and climate *** FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but mineral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate *** BAI was largest on the soil with the highest concentration of plant-available *** contrast to BAI,tree-ring chronologies did not differ among the study ***,tree-ring chronologies and BAI exhibited significantly positive correlations with summer precipitation,and negative correlations,with summer(December)temperature.A negative correlation was found betweenδ^(13)C and precipitation anomalies in the growing season(November-March).We interpret the negative correlations between growth and temperature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an impairment of net carbon assimilation by anomalously warm weather conditions during the growing *** conclude that the growth of *** is mainly affected by high temperature and low precipitation

关键词： Andisol annual ring dendroecology temperate broadleaf forest weather anomalies

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Marginal zone B cells are naturally reactive to collagen type II and are involved in the initiation of the immune response in collagen-induced arthritis

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Cellular & Molecular Immunology 2011年第4期8卷 296-304页

作者： cecilia Carnrot Kajsa E Prokopec Kristina Rasbo Mikael CI Karlsson Sandra Kleinau Department of Cell and Molecular Biology Uppsala UniversityUppsalaSweden Department of Medicine Unit of Clinical Allergy ResearchThe Karolinska InstituteSolnaSweden

Antibodies against type II collagen(CII)are essential for development of collagen-induced arthritis(CIA),but how and where the B-cell response to CII is initiated is not fully *** show here that naive DBA/1 mice display naturally reactive IgM and IgG anti-CII producing B cells prior to *** CII-reactive B cells were observed in the spleen and recognized as marginal zone(MZ)B *** CII immunization,CII-specific B cells expanded rapidly in the spleen,in contrast to the lymph nodes,with the initial response derived from MZ B cells and later by follicular(FO)B *** was evident despite that the MZ B cells were subject to stringent tolerance mechanisms by having a greater Fc gamma receptor IIb expression than the FO B ***,the MZ B cells migrated to the FO areas upon immunization,possibly providing antigen and activating FO T cells and subsequently FO B ***,around CIA onset increased numbers of IgG anti-CII producing FO B cells was seen in the spleen,which was dominated by IgG2a-and IgG2b-positive *** data demonstrate that CII-reactive MZ B cells are present before and expand after CII immunization,suggesting an initiating role of MZ B cells in the development of CIA.

关键词： arthritis B cells collagen type II ELISpot marginal zone mice

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A Model Structured in Classes for the Study of Student Population Evolution

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上海大学学报（自然科学版） 2014年第2期20卷 127-137页

作者： PEREIRA Edgar ROSA cecilia SILVA Jacques Department of Mathematics Universidade Federal do Rio Grande do Norte Department of Mathematics Instituto Politecnico da Guarda Department of Mathematics Universidade Federal do Rio Grande do Sul

This paper presents an application of a metapopulation model structured in classes for the study of population evolution of a network of *** global dynamics are considered in two parts,the local,where the evolution for each grade in a cycle is accounted,and the metapopulation or the movement of students between *** of the model is presented.

关键词：应用数学数学分析数学理论数学概念

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5-Azacytidine induces changes in electrophysiological properties of human mesenchymal stem cells

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Cell Research 2006年第12期16卷 949-960页

作者： Bartosz Balana cecilia Nicolett Ihor Zahanich Eva M Graf Torsten Christ Sabine Boxberger Department of Pharmacology and Toxicology Medical Clinic I Medical FacultyDresden University of TechnologyFetscherstr.74D-01307 DresdenGermany

Previously,mouse bone marrow-derived stem cells（MSC）treated with the unspecific DNA methyltransferase inhibi-tor 5-azacytidine were reported to differentiate into *** aim of the present study was to investigate theefficiency of a similar differentiation strategy in human mononuclear cells obtained from healthy bone marrow *** 1-3 passages,cultures were exposed for 24 h to 5-azacytidine（3μM）followed by 6 weeks of further *** treatment did not induce expression of myogenic marker MyoD or cardiac markers Nkx2.5 and GATA-4 and didnot yield beating cells during *** patch clamp experiments,approximately 10-15% of treated and untreatedcells exhibited L-type Ca2+ *** all cells showed outwardly rectifying K+currents of rapid or slow *** current amplitude at +60 mV doubled after 6 weeks of treatment compared with time-matched *** capacitance of treated cells was significantly larger than in controls 2 weeks after treatment and remained highafter 6 *** levels ofmRNAs for the K+channels Kv1.1,Kv1.5,Kv2.1,Kv4.3 and KCNMA1 and for theCa2+ channel Cav1.2 were not affected by *** with potassium channel blockers tetraethylammoniumand clofilium at concentrations shown previously to inhibit rapid or slowly activating K+currents of hMSC inhibitedproliferation of these *** results suggest that despite the absence of differentiation of hMSC into cardiomyocytes,treatment with 5-azacytidine caused profound changes in current density.

关键词： human mesenchymal stem cells 5-azacytidine cardiac differentiation outward K~+ currents

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18,X,Y aneuploidies and transmission electron microscopy studies in spermatozoa from five carriers of different reciprocal translocations

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Asian Journal of Andrology 2009年第3期11卷 325-332页

作者： Elena Moretti Nicola Antonio Pascarelli Valentina Giannerini Michela Geminiani cecilia Anichini Giulia Collodel Department of Biomedical Sciences Applied Biology Section University of Siena Siena 53100 Italy Department of Pediatrics Obstetrics and Reproductive Medicine University of Siena Siena 53100 Italy

We analysed ejaculated spermatozoa from five infertile men with different balanced reciprocal translocations to contribute to the study of meiotic segregation of chromosomes 18, X and Y and also to evaluate sperm morphology by transmission electron microscopy （TEM） analysis. Conventional lymphocyte karyotype analyses highlighted dif- ferent reciprocal balanced translocations： t（12; 13）, t（4;9）, t（X;8）, t（8; 10） and t（3; 16）. Semen analysis was performed by light and TEM. Fluorescence in situ hybridization was performed directly on sperm nuclei using centromeric probes for chromosomes 18, X and Y. The carriers of the balanced reciprocal translocations considered in the present study showed a very similar pattern of sperm pathologies： diffused presence of apoptosis and immaturity. All patients showed meiotic segregation derangements, highlighted by the presence of sperm diploidies and sex chromosome disomies particularly related to the failure of the first meiotic division. However, an increased incidence of chromosome 18 aneuploidy was detected in spermatozoa from t（X;8） and t（8;10） carriers. We have also reported values from sex chromosomes such as t（X;8）, although the X chromosome was involved in translocation. Since patients with reciprocal translocations and spermatogenetic impairment are candidates for intracytoplasmic sperm injection cycles, the study of sperm parameters, and particularly of the level of aneuploidy rates, would provide better information for couples at risk and would contribute to the data in the literature for a better understanding of the effects of chromosomal rearrangement on the whole meiotic process and, in particular, on chromosomes not involved in translocation.

关键词： electron microscopy fluorescence in situ hybridization altered karyotype spermatozoa reciprocal translocation

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The antiplasmodial effect of the extracts and formulated capsules of Phyllanthus amarus on Plasmodium yoelii infection in mice

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Asian Pacific Journal of Tropical Medicine 2011年第4期4卷 283-287页

作者： Tolulope O Ajala cecilia I Igwilo Ibrahim A Oreagba Oluwatoyin A Odeku Department of Pharmaceutics & Pharmaceutical Technology Faculty of PharmacyOlabisi Onabanjo University Department of Pharmaceutics and Pharmaceutical Technology Faculty of PharmacyUniversity of Lagos Department of Pharmacology College of MedicineUniversity of Lagos Department of Pharmaceutics and Industrial Pharmacy Faculty of PharmacyUniversity of Ibadan

Objective:To investigate the antiplasmodial activity of the extracts of Phyllanthus amarus(P. amarus) on Plasmodium yoelii(***)(a resistant malaria parasite strain used in animal stuthes) infection in ***:The aqueous and ethanol extracts of the whole plant of Phyllanthus amarus was administered to Swiss albino mice at doses of 200 mg/kg/day,400 mg/ kg/day,800 mg/kg/day and 1 600 mg/kg/day and the prophylactic and chemotherapeutic effect of the extracts against *** infection in mice was investigated and compared with those of standard antimalaria drugs used in the treatment of malaria parasite *** toxicity test was carried out in mice to determine the safety of the plant extract when administered orally. Results:The results showed that the extracts demonstrated a dose-dependent prophylactic and chemotherapeutic activity with the aqueous extracts showing slightly higher effect than the ethanol *** antiplasmodial effects of the extracts were comparable to the standard prophylactic and chemotherapeutic drugs used in chloroquine resistant Plasmodium infection although the activity depended on the dose of the extract *** extracts showed prophylactic effect by significantly delaying the onset of infection with the suppression of 79% at a dose of 1 600 mg/kg/***:The results obtained indicate that the extracts of the whole plant of *** possess repository and chemotherapeutic effects against resistant strains of *** in Swiss albino *** findings justify the use of the extract of *** in traditional medicine practice,for the treatment of malaria infections.

关键词： Antiplasmodial activity Phyllanthus amarus Plasmodium yoelli Artesunate/amodiaquine Pyrimethamine

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Proteomic insights on the metabolism in inflammatory bowel disease

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World Journal of Gastroenterology 2020年第7期26卷 696-705页

作者： Laura Francesca Pisani Manuela Moriggi cecilia Gelfi Maurizio Vecchi Luca Pastorelli Gastroenterology and Digestive Endoscopy Unit IRCCS Policlinico San DonatoSan Donato Milanese 20097Italy Department of Biomedical Science for Health University of the Study of MilanIRCCS Istituto Ortopedico GaleazziMilan 20122Italy Gastroenterology and Endoscopy Unit IRCCS Ca'Granda FoundationPoliclinico HospitalUniversity of the Study of MilanMilan 20122Italy Department of Biomedical Science for Health University of the Study of MilanMilan 20122Italy

Inflammatory bowel diseases(IBD)are chronic and relapsing inflammatory conditions of the gut that include Crohn's disease and ulcerative *** pathogenesis of IBD is not completely unraveled,IBD are multi-factorial diseases with reported alterations in the gut microbiota,activation of different immune cell types,changes in the vascular endothelium,and alterations in the tight junctions’structure of the colonic epithelial *** represents a useful tool to enhance our biological understanding and to discover biomarkers in blood and intestinal *** is expected to provide reproducible and quantitative data that can support clinical assessments and help clinicians in the diagnosis and treatment of *** a differential diagnosis of Crohn's disease and ulcerative colitis and the prediction of treatment response can be deducted by finding meaningful *** some non-invasive biomarkers have been described,none can be considered as the“gold standard”for IBD diagnosis,disease activity and therapy *** these reason new studies have proposed an“IBD signature”,which consists in a panel of biomarkers used to assess *** above described approach characterizes“omics”and in this review we will focus on proteomics.

关键词： Proteomics Inflammatory bowel disease Cronh’s disease Ulcerative colitis Proteins Biomarkers discovery

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Dynamics of populations with two sexes

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International Journal of Biomathematics 2015年第4期8卷 127-144页

作者： M. cecilia Perez E. Adriana Saavedra Mariano A. Ferrari Facultad de Ingenieria Universidad Nacional de la Patagonia San Juan Bosco Esquel Chubut Argentina Facultad de Ingenieria Universidad Nacional de la Patagonia San Juan Bosco Trelew Chubut Argentina Facultad de Ingenierla Universidad Nacional de la Patagonia San Juan Bosco Puerto Madryn Chubut Argentina Centro Nacional Patagdnico CONICET Puerto Madryn Chubut Argentina

A mathematical model is presented in order to describe the dynamics of polygamous populations, bearing in mind single individuals of both sexes and the development of reproductive groups. In this context, the description leads us to consider positive homogeneous dynamical systems, establishing conditions for the stationary state existence and its local stability. A fourth pre-reproductive stage was considered, i.e. males and females spend part of their lives before being in condition to reproduce, as a first step to consider more general models. Finally, we parametrized the proposed model using southern elephant seal data, to analyze the direct applicability to a real population.

关键词： Dynamical systems two-sex model mating system local stability.

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