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Production Process and Properties of a Highly Porous Al Alloy Made Using NaCl Droplets as a Space Holder

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1034-1040页

作者： Manuela Covaciu Andrew richard kennedy Faculty of Engineering University of Nottingham Faculty of Material Science and Engineering Universitatea Tehnica din Cluj-Napoca School of Engineering Pontificia Universidad Católica de Chile

Porous Al structures have been made using a porogen leaching method but with additional novel steps. In this way, Al-0.25Cu-0.6Si-1.0Mg alloys with interconnected, open cells have been made, with high levels of porosity（up to 89%）. The use of 4 to 5 mm diameter sodium chloride droplets combined with interspersion of the metal powder and droplets in the die and dissolution of the salt before sintering was found to enable easier interspersion of the two components, resulting in good connectivity of the beads via the formation of ‘‘windows＇＇ between the pores, and rapid elimination of salt from the structure. Porous Al with densities in the range of 0.28–0.86 g/cm3 exhibited compressive yield strengths in the range of 0.14 to 7.5 MPa, with no difference being observed between the samples made by this route and by more conventional dissolution of the salt after sintering. These novel steps widen the possibility for porous metal manufacture to other materials, not limited by the need to have a sintering temperature below that for the melting point of salt.

关键词： Aluminium alloy Sodium chloride Porous metal

From mouse to man——a bridge too far?

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National Science review 2020年第7期7卷 1258-1259页

作者： Henry kennedy Colette Dehay Univ Lyon Université Claude Bernard Lyon 1 Inserm Stem Cell and Brain Research Institute U1208 Institute of Neuroscience Chinese Academy of Sciences

The contemplation of our demise, particularly via the loss of cognitive functions, is challenging for our species. While we seek to understand our brain and its action as a particularly intriguing manifestation of the physical universe, society also seeks solutions to concrete problems and, here, understanding the brain as an intellectual exercise must be extended to being able to maintain and repair its function. Just how difficult this is be-

关键词： VISUAL-COrTEX CIrCUIT BrAIN FEATUrES

Thermal bleaching of optical absorption and photoluminescence spectra of γ-irradiated CaF_2:Dy:Pb:Na single crystals

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Journal of rare Earths 2010年第4期28卷 493-497页

作者： S.M. Moses kennedy Department of Physics S.S.N. College of Engineering Rajiv Gandhi Salai Kalavakkam-603 110 Chennai Tamil Nadu India

The variation of the optical absorption (OA) and photoluminescence (PL) spectra with temperature was studied on γ-irradiated CaF2:Dy:Pb:Na single crystals. The OA spectrum showed bands around 2.05, 3.20, 3.82 and 6.20 eV which could be attributed to different sodium associated (SA) colour centres (CCs) such as MNa and rA+ . Heating the crystal indicated the annihilation and formation of different SACCs. The excitation spectrum for the characteristic Dy3+ emission at 2.14 eV immediately after irradiation was...

关键词： calcium fluoride optical absorption photoluminescence colour centres dysprosium lead sodium rare earths

A column study of the hydro-mechanical behavior of mature fine tailings under atmospheric drying

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International Journal of Mining Science and Technology 2017年第2期27卷 203-209页

作者： Anis roshani Mamadou Fall Kevin kennedy Department of Civil Engineering University of OttawaOttawa KIN 6N5Canada

In this paper, the hydro-mechanical behavior and physical properties of mature fine tailings(MFT) under atmospheric drying are investigated through a column study. In the study, evaporation takes place in the development of suction in the upper parts of the column and increasing suction leads to higher strength in the tailings. After 5 days, the suction in the first lift is around 17 k Pa in the upper part of the *** a second lift is added, the first lift initially loses strength but over a 30 days' period, the strength is recovered to its prior value and suction in the second lift reaches 500 k Pa. The vane shear strength values show a substantial increase in the strength of the MFT after 30 days under atmospheric drying and drainage. The 90% strength found in the column exceeds the threshold(5 k Pa). The hydraulic-mechanical properties of the deposited tailings are closely coupled due to several mechanisms, such as evaporation,drainage, self-consolidation, suction and crack development. The findings of this study will provide a better understanding of the placement behavior of multiple lifts of MFT and thus contribute to reclamation design standards and reduce the use of dedicated disposal areas.

关键词： Tailings Oil sand Environment Drying Multi-lift deposition

Thermoluminescence studies on γ-irradiated CaF_2:Dy:Pb:Na single crystals

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Journal of rare Earths 2009年第2期27卷 187-191页

作者： S.Masilla Moses kennedy Department of Physics SSN College of EngineeringSSN NagarRajiv Gandhi SalaiChennai-603 110Tamil Nadu India

Therrnoluminescence （TL） glow, thermoluminescence emission （TLE） and thermal decay （TD） of optical absorption （OA） bands were studied on γ-irradiated CaF2：Dy （0.010at.%）：Pb （0.188at.%）：Na （0.026at.%） single crystals （hereafter called crystal-I）. The TL glow exhibited four glow peaks in the temperature region 300-500 K. The TL response with dose was studied up to -7.5 kGy. The total glow showed linear, supra linear and exponential growth with dose. The TLE showed bands characteristic of Dy^3＋ ions （around 1.65, 1.87, 2.18 and 2.63 eV） and sodium associated （SA） colour centres （CCs） such as MNa （around 1.67 eV） and XNa （a new SA CC, with an emission band around 2.63 eV）. The OA bands of MNa CC around 3.23 and 2.07 eV were found to decrease with temperature almost in accordance with the TL glow. The r＋A centre absorption around 2.48 eV was found to grow with temperature initially and then decayed. The formation/growth of the CCs r＋A and XNa might be from the conversion of the irradiation produced CC MNa. An attempt was made to explain the TL mechanism in the present system.

关键词： CaF2:Dy:Pb:Na thermoluminescence thermoluminescence emission colour centres rare earths

The immune tolerant phase of chronic HBV infection： new perspectives on an old concept

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Cellular & Molecular Immunology 2015年第3期12卷 258-263页

作者： Antonio Bertoletti Patrick T kennedy Emerging Infectious Diseases (EID) Program Duke-NUS Graduate Medical School Singapore Viral Hepatitis Laboratory Singapore Institute for ClinicalSciences Agency of Science Technology and Research (A＊STAR) Singapore and Blizard Institute Barts and The London School of Medicine & DentistryLondon UK

Chronic hepatitis B virus （HBV） infection progresses through distinct disease phases that are strongly associated with patient age. The so-called immune tolerant （IT） phase represents the classical early phase of infection; it is associated with high levels of HBV replication and lack of clinical signs of liver Inflammation. Whether this phase of HBV infection is also associated with immunological features of ＂tolerance＇ has recently been challenged. Here, we review the data that dispute this concept of immune tolerance and then propose an alternative interpretation of the immunopathological events that take place during this early phase of CHB infection.

关键词： Hepatitis B antiviral immunity T cells

Multimodal comparison of plasma proteins associated with blood-brain barrier impairment in Alzheimer’s disease

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Aging Communications 2024年第1期6卷 1-9页

作者： Elisa Giunti roberto Collu Joel reisman Jong Soo lee Noureddine Melikechi Weiming Xia Geriatric research Education and Clinical Center Bedford VA Healthcare SystemBedfordMA 01730U.S.A Department of Pharmacology Physiology and BiophysicsBoston University Chobanian&Avedisian School of MedicineBostonMA 02118U.S.A Center for Healthcare Organization and Implementation research Bedford VA Healthcare SystemBedfordMA 01730U.S.A kennedy College of Science University of Massachusetts LowellLowellMA 01854U.S.A.

Background:Vascular impairment is one of the major contributors to *** aimed to identify blood biomarkers suggestive of potential impairment of the blood-brain barrier(BBB)in subjects with Alzheimer’s disease(AD).Methods:We used administrative data from the VA Informatics and Computing Infrastructure resource Center to study both inpatients and outpatients with *** samples from healthy control and AD individuals were analyzed using enzyme-linked immunosorbent assay and proteomics approaches to identify differentially expressed *** analysis was applied to explore significantly enriched ***:In the same cohort of patients with AD,we found twice number of subjects with cerebral amyloid angiopathy in the two-year period after the onset of AD,compared to the number of subjects with cerebral amyloid angiopathy in the two-year period prior to AD *** pathways related to BBB,like cell adhesion,extracellular matrix organization and Wnt signaling,were activated and differentially expressed proteins such as ADAM22,PDGFr-α,DKK-4,Neucrin and rSOP-1 were ***,matrix metalloproteinase-9,which is implicated in causing degradation of basal lamina and BBB disruption,was significantly increased in the plasma of AD ***:Alteration of proteins found in AD subjects could provide new insights into biomarkers regulating permeability and BBB integrity.

关键词： Alzheimer’s disease blood-brain barrier peripheral biomarkers matrix metalloproteinases cerebral amyloid angiopathy

Electronic behavior of native oxide films on Ti and TiN during 90-day immersion in electrolytes with different pH levels

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rare Metals 2021年第3期40卷 582-589页

作者： Amir Poursaee Golnaz Najaf-Tomaraei Marian S.kennedy Department of Materials Science and Engineering and Glenn Department of Civil Engineering Clemson UniversityClemsonSC 29634USA Department of Materials Science and Engineering Clemson UniversityClemsonSC 29634USA

This work presents the electronic behavior of Ti and TiN thin films when exposed to electrolytes with pH levels of 2,7 and 13 for 90 *** potentio-electrochemical impedance spectroscopy tests were performed on the 100-nm Ti and TiN monolithic films,and MottSchottky analysis of these tests was used to determine the films’ semiconductive behavior and changes in the donor/acceptor *** addition,the flat-band potential of each film’s surface oxide was also *** attempt was made to control oxide formation,and therefore,these tests reflected the native surfaces of these *** the TiN films exhibited n-type semiconductivity in all electrolytes,the Ti films only showed n-type behavior in the acidic(pH=2) and neutral(pH=7) *** semiconductivity of the Ti films transitioned to p-type during exposure to the basic electrolyte(pH=13) after reaching 60 ***,there was a significant increase in the donor densities for both Ti and TiN films when immersed in the basic electrolyte relative to the acidic and neutral electrolytes.

关键词： Ti TiN Thin films Mott-Schottky analysis Semiconductivity

Assessing the migratory histories, trophic positions, and conditions of lake sturgeon in the St. Croix and Mississippi rivers using fn ray microchemistry, stable isotopes, and fatty acid profles

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Ecological Processes 2021年第1期10卷 1021-1042页

作者： Jefrey r.Ziegeweid Michelle r.Bartsch Lynn A.Bartsch Steven J.Zigler robert J.kennedy Seth A.Love U.S.Geological Survey California Water Science Center6000 J StPlacer HallSacramentoCA 95819USA. U.S.Geological Survey Upper Midwest Water Science Center2280 Woodale DrMounds ViewMN 55112USA. U.S.Geological Survey Upper Midwest Environmental Sciences Center2630 Fanta Reed RoadLa CrosseWI 54603USA. Division of Fisheries Illinois Department of Natural Resources13608 Fox RoadYorkvilleIL 60560USA.

Background:reproducing populations of invasive carps(Hypophthalmichthys spp.)could alter aquatic food webs and negatively afect native fshes in the Mississippi National river and recreation Area(MISS)and the *** National Scenic riverway(SACN).However,proposed invasive carp barriers may also threaten populations of native migratory fshes by preventing movements of fsh between rivers that are necessary for life history *** this study,nonlethal chemical techniques were used to provide baseline data related to the condition,trophic position,and migratory histories of lake sturgeon(Acipenser fulvescens)captured in the Mississippi and *** ***:Fish length and weight measurements and age estimates determined from pectoral fn rays demonstrated that lake sturgeon from the Mississippi river had greater lengths-at-age compared to sturgeon from the *** ***,length–weight relations were similar for sturgeon from the Mississippi and *** *** sturgeon captured from diferent locations had distinguishable fatty acid signatures,and stable isotope analyses demonstrated that lake sturgeon from the Mississippi river generally feed at a higher trophic level than those in the *** ***-to-calcium ratios(Sr:Ca)from fn ray cross sections indicated that sturgeon captured from the Mississippi river had higher Sr:Ca values than sturgeon captured from the *** river,and natal origins and capture locations were not signifcantly diferent among sturgeon captured within individual *** sturgeon were captured in water with a similar Sr:Ca signature as their natal waters,indicating that there is some separation between populations of lake sturgeon in the *** and Mississippi ***,Sr:Ca data indicated substantial variation in movement patterns among individual lake sturgeon,indicating that populations interact through migrations of individual fsh between ***:Study results provide baseline c

关键词： Fin ray microchemistry Stable isotopes Fatty acids Lake sturgeon St.Croix river Mississippi river National park Strontium Calcium