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Acta Metallurgica Sinica(English letters) 2006年第1期19卷 9-19页

作者： W.M. Zeng H.l. Wu j. Zhang East China University of Science and Technology Shanghai 200237 China The University of Texas at El Paso-MetaUurgy and Materials Engineering Texas 79902 USA

Tool condition is one of the main concerns in friction stir welding （FSW）, because the geometrical condition of the tool pin including size and shape is strongly connected to the microstrueture and mechanical performance of the weld. Tool wear occurs during FSW, especially for welding metal matrix composites with large amounts of abrasive particles, and high melting point materials, which significantly expedite tool wear and deteriorate the mechanical performance of welds. Tools with different pin-wear levels are used to weld 6061 Al alloy, while acoustic emission （AE） sensing, metallographic sectioning, and tensile testing are employed to evaluate the weld quality in various tool wear conditions. Structural characterization shows that the tool wear interferes with the weld quality and accounts for the formation of voids in the nugget zone. Tensile test analysis of samples verifies that both the ultimate tensile strength and the yield strength are adversely affected by the formation of voids in the nugget due to the tool wear. The failure location during tensile test clearly depends on the state of the tool wear, which led to the analysis of the relationships between the structure of the nugget and tool wear. AE signatures recorded during welding reveal that the AE hits concentrate on the higher amplitudes with increasing tool wear. The results show that the AE sensing provides a potentially effective method for the on-line manitoring of tool wear.

关键词： acoustic emission online monitoring tool wear 6061 Al alloy

A decision framework for identifying models to estimate forest ecosystem services gains from restoration

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Forest Ecosystems 2016年第2期3卷 126-137页

作者： Zachary l. Christin Kenneth j. Bagstad Michael A. Verdone Earth Economics 107 N Tacoma Ave Tacoma WA 98403 USA. U.S. Geological Survey Geosciences & Environmental Change Science Center Box 25046 MS 980 Denver CO 80225 USA. International Union for the Conservation of Nature 1630 Connecticut Ave. NW #300 Washington DC 20009 USA.

Restoring degraded forests and agricultural lands has become a global conservation priority. A growing number of tools can quantify ecosystem service tradeoffs associated with forest restoration. This evolving ＂tools landscape＂ presents a dilemma： more tools are available, but selecting appropriate tools has become more challenging. We present a Restoration Ecosystem Service Tool Selector （RESTS） framework that describes key characteristics of 13 ecosystem service assessment tools. Analysts enter information about their decision context, services to be analyzed, and desired outputs. Tools are filtered and presented based on five evaluative criteria： scalability, cost, time requirements, handling of uncertainty, and applicability to benefit-cost analysis. RESTS uses a spreadsheet interface but a web-based interface is planned. Given the rapid evolution of ecosystem services science, RESTS provides an adaptable framework to guide forest restoration decision makers toward tools that can help quantify ecosystem services in support of restoration.

关键词： Decision support Ecosystem services Forest restoration Modeling Valuation Comparative toolsassessment

Recognition of nestmate eggs in the ant Formicafusca is based on queen derived cues

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Current Zoology 2014年第1期60卷 131-136页

作者： Heikki HElANTERA Stephen j. MARTIN Francis l.W. RATNIEKS Centre of Excellence in Biological Interactions Department of Biosciences POB 65 University of Helsinki Finland School of Environment & life Sciences University of Salford Manchester M5 4WT UK laboratory ofApiculture & Social Insects (lASI) School of Life Sciences University of Sussex Falmer Brighton UK

Inclusive fitness benefits depend on recognizing the right individuals to interact with. Social insect nests protect themselves from non-kin intruders through nestmate recognition based on chemical cues. The recognition cues on adult individu- als are from a mixture of genetic and environmental sources, but the ontogeny and use of recognition cues on eggs has not been previously assessed. We studied recognition by workers of eggs that were either nestmates or non-nestmates, and the ontogeny of recognition cues on eggs in the ant Formica fusca, a species with precise egg recognition abilities. Workers were able to dis- criminate among freshly laid eggs with no nest derived cues on them, and the egg surface chemicals varied among nests in these eggs, suggesting that queen derived cues are used in nestmate recognition. The results are discussed in the light of their implica- tions on deceptive social parasite strategies and within colony conflicts

关键词： Nestmate recognition Social insects Social parasitism Formicafusca Cuticular hydrocarbons

Acetaminophen and zinc phosphide for lethal management of invasive lizards Ctenosaura similis

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Current Zoology 2011年第5期57卷 625-629页

作者： Michael l. AVERY j.hn D. EISEMANN Kandy l. KEACHER Peter j. SAVARIE United States Department of Agriculture Wildlife Services National Wildlife Research Center Florida Field Station 2820 East University Avenue Gainesville FL 32641 USA United States Department of Agriculture Wildlife Services National Wildlife Research Center Ft. Collins CO 80225 USA

Reducing populations of invasive lizards through trapping and shooting is feasible in many cases but effective inte-grated management relies on a variety of tools, including toxicants. In Florida, using wild-caught non-native black spiny-tailed iguanas Ctenosaura similis, we screened acetaminophen and zinc phosphide to determine their suitability for effective population management of this prolific invasive species. Of the animals that received acetaminophen, none died except at the highest test dose, 240 mg per lizard, which is not practical for field use. Zinc phosphide produced 100% mortality at dose levels as little as 25 mg per lizard, equivalent to about 0.5% in bait which is lower than currently used in commercial baits for commensal rodent con-trol. We conclude that zinc phosphide has potential as a useful tool for reducing populations of invasive lizards such as the black spiny-tailed iguana provided target-selective delivery methods are developed [Current Zoology 57 （5）： 625~529, 2011].

关键词： Acetaminophen Black spiny-tailed iguana Ctenosaura similis Florida Invasive Zinc phosphide

Numerical Investigation of a Refractive Index SPR D-Type Optical Fiber Sensor Using COMSOl Multiphysics

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Photonic Sensors 2013年第1期3卷 61-66页

作者： D. F. SANTOS A. GUERREIRO j. M. baptista Centro de Ciēncias Exatas e da Engenharia Universidade da Madeira Funchal Portugal Faculdade de Ciēncias da Universidade do Porto Portugal INESC TEC Porto Portugal

Recently, many programs have been developed for simulation or analysis of the different parameters of light propagation in optical fibers, either for sensing or for communication purposes. In this paper, it is shown the COMSOl Multiphysics as a fairly robust and simple program, due to the existence of a graphical environment, to perform simulations with good accuracy. Results are compared with other simulation analysis, focusing on the surface plasmon resonance （SPR） phenomena for refractive index sensing in a D-type optical fiber, where the characteristics of the material layers, in terms of the type and thickness, and the residual fiber cladding thickness are optimized.

关键词： Refractive index sensor optical fiber sensor surface plasmon resonance light propagation simulation COMSOl Multiphysics graphical environment

j.ffery-Hamel flow of non-Newtonian fluid with nonlinear viscosity and wall friction

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Applied Mathematics and Mechanics(English Edition) 2017年第6期38卷 815-830页

作者： j. NAGlER Department of Fluid Mechanics and Heat Transfer Faculty of Engineering Tel-Aviv University Ramat-Aviv 69978 Israel

A j.ffery-Hamel （j.H） flow model of the non-Newtonian fluid type inside a convergent wedge （inclined walls） with a wall friction is derived by a nonlinear ordinary differential equation with appropriate boundary conditions based on similarity relationships. Unlike the usual power law model, this paper develops nonlinear viscosity based only on a tangential coordinate function due to the radial geometry shape. Two kinds of solutions are developed, i.e., analytical and semi-analytical （numerical） solutions with suitable assumptions. As a result of the parametric examination, it has been found that the Newtonian normalized velocity gradually decreases with the tangential direction progress. Also, an increase in the friction coefficient leads to a decrease in the normalized Newtonian velocity profile values. However, an increase in the Reynolds number causes an increase in the normalized velocity function values. Additionally, for the small values of wedge semi-angle, the present solutions are in good agreement with the previous results in the literature.

关键词： j.ffery-Hamel (j.H) flow slip condition non-Newtonian fluid friction,nonlinear viscosity analytical solution numerical solution approximate solution

Combinatorial therapies for spinal cord inj.ry repair

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Neural Regeneration Research 2025年第5期20卷 1293-1308页

作者： Carla S.Sousa Andreia Monteiro António j.Salgado Nuno A.Silva life and Health Sciences Research Institute(ICVS) School of MedicineUniversity of MinhoCampus de Gualtar-gualtarBragaPortugal ICVS/3B’s Associate lab PT Government Associated LabCampus de Gualtar-gualtarBragaPortugal

Spinal cord inj.ries have profound detrimental effects on individuals, regardless of whether they are caused by trauma or non-traumatic events. The compromised regeneration of the spinal cord is primarily attributed to damaged neurons, inhibitory molecules, dysfunctional immune response, and glial scarring. Unfortunately, currently, there are no effective treatments available that can fully repair the spinal cord and improve functional outcomes. Nevertheless, numerous pre-clinical approaches have been studied for spinal cord inj.ry recovery, including using biomaterials, cells, drugs, or technological-based strategies. Combinatorial treatments, which target various aspects of spinal cord inj.ry pathophysiology, have been extensively tested in the last decade. These approaches aim to synergistically enhance repair processes by addressing various obstacles faced during spinal cord regeneration. Thus, this review intends to provide scientists and clinicians with an overview of pre-clinical combinatorial approaches that have been developed toward the solution of spinal cord regeneration as well as update the current knowledge about spinal cord inj.ry pathophysiology with an emphasis on the current clinical management.

关键词： electric stimulation neural tissue regeneration neuroprotection polytherapy spinal cord inj.ry

ElECTROCHEMICAl STUDY ON THE lOCAlIZED CORROSION OF TWO DIFFERENT TEMPER lY12 AllOYS

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Acta Metallurgica Sinica(English letters) 2005年第5期18卷 609-619页

作者： F.H. Cao l. Guo l.j. Zhang Z. Zhang j. Q. Zhang Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China State Key laboratory for Corrosion and Protection of Metals Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The corrosion behavior of two different aged lY12 alloys in EXCO （234g/l NaCl, 50g/l KNO3 0.1M HNO3） and MIl-H-600 （35g/l NaCl, 5g/l （NH4）2SO4） solutions were studied using electrochemical impedance spectroscopy （EIS） in conj.nction with SEM technique respectively, and the pH variation of the above accelerated corrosion solution during materials corroding was also measured to characterize the corrosion processes. At the beginning of corrosion, EIS plots exhibited two capacitive arcs in the high frequency range （Cd） and mediate frequency range （ Cf） originating from the original corroded surface and the newly formed interface respectively, and a low frequency inductive loop due to the relaxation phenomenon of reaction intermediates. In the EXCO,solution, the EIS results showed that once the exfoliation corrosion occurred, the inductive loop disappeared. The results also showed that the exfoliation corrosion susceptibility of state T6 is much higher than that of state T3, but the intergranular corrosion susceptibility has a reverse order. Based on the relationship of EIS results with SEM and metalloscopy morphologies of the corroding substrates and physic-chemical meaning of EIS parameters, an index （Cf/Cd） has been proposed to characterize the extent of the localized corrosion, which variation tallies with the real corrosion extent correctly. Meanwhile, good agreement was found between the experimental results and the electrochemical model proposed and, good coherence between the electrochemical features and the distribution type of constituent particles of corroding material was observed.

关键词： electrochemical impedance spectroscope lY12 alloy exfoliation corrosion intergranular corrosion

Increase in the Hydrophilicity and lewis Acid-Base Properties of Solid Surfaces Achieved by Electric Gliding Discharge in Humid Air: Effects on Bacterial Adherence

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Plasma Science and Technology 2009年第2期11卷 187-193页

作者： j.O.KAMGANG M.NAITAlI j.-M.HERRY M.-N.BEllON-FONTAINE j.-l.BRISSET R.BRIANDET laboratory of Interfacial Electrochemistry and Analytical Chemistry University of Rouen INRA(National Institute for Agricultural Research) UMR 763 Bio-adhesion and Hygiene of Materials AgroParisTech UMR 763 Bio-adhesion and Hygiene of Materials AgroParisTech UMR763 Bio-adhesion and Hygiene of Materials

This study addressed the effects of treatment with gliding discharge plasma on the surface properties of solid materials, as well as the consequences concerning adherence of a model bacterium. As evaluated by contact angles with selected liquids, plasma treatment caused an increase in surface hydrophilicity and in the lewis acid-base components of the surface energy of all materials tested. These modifications were more marked for low density polyethylene and stainless steel than for polytetrafiuoroethylene. After treatment, the hydrophilicity of the materials remained relatively stable for at least 20 days. Moreover, analysis of the topography of the materials by atomic force microscopy revealed that the roughness of both polymers was reduced by glidarc plasma treatment. As a result of all these modifications, solid substrates were activated towards micro-organisms and the adherence of S. epidermidis, a negatively charged lewis-base and mildly hydrophilic strain selected as the model, was increased in almost all the cases tested.

关键词： gliding arc plasma surface energy properties polymers stainless steel surface hydrophilicity atomic force microscopy

How important is donor age in liver transplantation?

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World j.urnal of Gastroenterology 2016年第21期22卷 4966-4976页

作者： Alberto lué Estela Solanas Pedro baptista Sara lorente j.an j.Araiz Agustin Garcia-Gil M Trinidad Serrano liver Transplantation Unit Department of Gastroenterology University Hospital Lozano Blesa 50009 Zaragoza Spain Health Research Institute of Aragon (IIS) 50009 Zaragoza Spain Centro de Investigacion Biomedica en Red Enfermedades Hepaticas y Digestivas (CiberEHD) 28029 Madrid Spain Transplant Coordination University Hospital Lozano Blesa 50009 Zaragoza Spain liver Transplant Unit Department of Surgery University Hospital Lozano Blesa 50009 Zaragoza Spain

The age of liver donors has been increasing in the past several years because of a donor shortage. In the United States, 33% of donors are age 50 years or older, as are more than 50% in some European countries. The impact of donor age on liver transplantation(lT) has been analyzed in several studies with contradictory conclusions. Nevertheless, recent analyses of the largest databases demonstrate that having an older donor is a risk factor for graft failure. Donor age is included as a risk factor in the more relevant graft survival scores, such as the Donor Risk Index, donor age and Model for End-stage liver Disease, Survival Outcomes Following liver Transplantation, and the Balance of Risk. The use of old donors is related to an increased rate of biliary complications and hepatitis C virus-related graft failure. Although liver function does not seem to be significantly affected by age, the incidence of several liver diseases increases with age, and the capacity of the liver to manage or overcome liver diseases or external inj.ries decreases. In this paper, the importance of age in lT outcomes, the role of donor age as a risk factor, and the influence of aging on liver regeneration are reviewed.

关键词： liver transplantation liver regeneration Graft survival Old donor Aging