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Numerical Simulation of Temperature Distribution and ThermalStress Field in a Turbine Blade with Multilayer-Structure TBCs by a Fluid–Solid Coupling Method

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Journal of Materials Science & Technology 2016年第5期32卷 452-458页

作者： w.Z.Tang L.Yang w.Zhu Y.C.Zhou J.w.Guo C.LU Key Laboratory of Key Film Materials and Application for Equipment(Hunan Province) School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China Hunan Provincial Key laboratory of Thin Film Materials and Devices School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China School of Mechanical Engineering Xiangtan University Xiangtan 411105China Department of Mechanical Engineering Curtin UniversityPerthWA 6845Australia

To study the temperature distribution and thermal-stress field in different service stages, a two-dimensional model of a turbine blade with thermal barrier coatings is developed, in which the conjugate heat transfer analysis and the decoupled thermal-stress calculation method are adopted. Based on the simulation results, it is found that a non-uniform distribution of temperature appears in different positions of the blade surface, which has directly impacted on stress field. The maximum temperature with a value of 1030 ℃ occurs at the leading edge. During the steady stage, the maximum stress of thermally grown oxide （TGO） appears in the middle of the suction side, reaching 3.75 GPa. At the end stage of cooling, the maximum compressive stress of TGO with a value of-3.5 GPa occurs at the leading edge. Thus, it can be predicted that during the steady stage the dangerous regions may locate at the suction side, while the leadine edge mav be more Drone to failure on cooling.

关键词： Thermal barrier coatings Temperature distribution Thermal-stress field Conjugate heat transfer Decoupled thermal-stress calculation Fluid–solid coupling

A CUMULATIVE FATIGUE DAMAGE RULE UNDER THE ALTERNATIVE OF CORROSION OR CYCLIC LOADING

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 65-71页

作者： w.X. Yao Department of Aircraft Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time, loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.

关键词： corrosion fatigue cumulative fatigue damage rule Miner's rule

MOLECULAR DYNAMICS SIMULATION OF STRUCTURE STABILITY OF SILVER NANOCLUSTERS

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 209-214页

作者： w.H. Qi School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 China School of Materials Science and Engineering Central South University Changsha 410083 China

The structures of Ag clusters with sizes n=13 to 1157 are studied by tight binding molecular dynamics simulation. It is found that the stable structures of Ag clusters follow the sequence amorphous-crystalline-amorphous-crystalline with the cluster size increasing from 13 to 1157. Furthermore, all the shells of Ag clusters are different from the structure of the corresponding bulk Ag.

关键词： structure stability molecular dynamics silver nanoclusters

Coordinated Cluster/Double Star observations of dayside flux transfer events on 6 April 2004

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Science China(Technological Sciences) 2008年第10期51卷 1611-1619页

作者： Malcom w. DUNLOP Space Science and Technology Department Rutherford Appleton Laboratory Chilton Oxfordshire OX 11 0QX UK

with the Double Star Program TC1 in the equatorial orbit and Cluster tetrahedron in the high latitude polar orbit, a conjunct observation of FTEs on the dayside magnetopause (MP) on April 6, 2004 is presented in this study. The FTEs observed by TC1 at low latitudes are characterized to be generated in the subsolar region and the obtained flux tube axes orientate along the predicted low latitude component magnetic reconnection X-line, indicating that these FTEs were more likely to be generated through multiple X-line reconnection or single X-line bursty reconnec-tion. During the same period, Cluster also encountered a series of magnetosheath FTEs with their axes pointing roughly along the interplanetary magnetic field. At last, the global FTE configuration is obtained from observations in different loca-tions, which is in good agreement with the "elbow shape" model.

关键词： magnetopause magnetic reconnection FTEs generation mechanism global configuration

Could contact lens dryness discomfort symptoms sometimes have a neuropathic basis?

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Eye and Vision 2021年第1期8卷 101-108页

作者： Charles w.McMonnies School of Optometry and Vision Science Faculty of Medicine and HealthUniversity of New South Wales77Cliff AvenueNorthbridge Sydney 2063Australia

Symptoms of dryness discomfort in soft contact lens wearers frequently lead to discontinuation from *** negative influence of pre-fitting tear dysfunctions appears likely to be exacerbated by the challenges to tear homeostasis caused by contact *** corneal mechanisms for symptoms in contact lens wearers are different to those for dry eye disease because the cornea is insulated by the lens from ambient conditions as well as from lid wiper friction during *** of dryness discomfort might be the consequence of increased lid wiper friction during blinking when the lens front surface becomes soiled and dry and exhibits very rapid tear break *** is possible that some cases of contact lens intolerance and discontinuation could be a function of lid wiper *** relation to the possibility of corneal neuropathy,a stagnant post-lens tear pool with the possibility of increased concentrations of metabolic by-products,cellular debris,and bacterial exotoxins,might have the potential to disturb the corneal epithelial and sub-basal *** by contact lens-induced inflammation to any neuropathic changes may partly depend on the degree to which inflammatory mediators are concentrated in a stagnant post-lens tear *** does not appear to be known if corneal neuropathic changes could develop under these *** chances of neuropathic involvement may be greater if discomfort develops after a significant period of successful wear and there is a history of comorbid pain *** and in vivo confocal microscopy in discontinued contact lens wearers may support a diagnosis of contact lens-related corneal neuralgia.

关键词： Contact lens Symptoms Neuropathy Sub-basal nerve plexus

Migratory flight of insect pests within a year-round distribution: European corn borer as a case study

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Journal of Integrative Agriculture 2018年第7期17卷 1485-1505页

作者： Thomas w.Sappington Corn Insects and Crop Genetics Research Unit Agricultural Research ServiceUSDA

Insect migratory flight differs fundamentally from most other kinds of flight behavior, in that it is non-appetitive. The adult is not searching for anything, and migratory flight is not terminated by encounters with potential resources. Many insect pests of agricultural crops are long-distance migrants, moving from lower latitudes where they overwinter to higher latitudes in the spring to exploit superabundant, but seasonally ephemeral, host crops. The migratory nature of these pests is somewhat easy to recognize because of their sudden appearance in areas where they had been absent only a day or two earlier. Many other serious pests survive hostile winter conditions by diapausing, and therefore do not require migration to move between overwintering and breeding ranges. Yet there is evidence of migratory behavior engaged in by several pest species that inhabit high latitudes year-round. In these cases, the consequences of migratory flight are not immediately noticeable at the population level, because migration takes place for the most part within their larger year-round distribution. Nevertheless, the potential population-level consequences can be quite important in the contexts of pest management and insect resistance management. As a case study, I review the evidence for migratory flight behavior by individual European corn borer adults, and discuss the importance of understanding it. The kind of migratory behavior posited for pest species inhabiting a permanent distribution may be more common than we realize.

关键词： migration dispersal flight movement ecology European corn borer Ostrinia nubilalis

Continuous solutions for fractional integral inclusion in locally convex topological space

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 175-183页

作者： Rabha w.Ibrahim School of Mathematical Sciences Faculty of Sciences and Technology

The existence of continuous solutions for fractional integral inclusion via its singlevalued problem and fixed point theorem for set-valued function in locally convex topological spaces is discussed. The proof of the single-valued problem will be based on the Leray- Schauder fixed point theorem. Moreover, the controllability of this solution is studied.

关键词： Riemann-Liouville integral operator integral inclusion set-valued function

A different view： sensory drive in the polarized-light realm

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Current Zoology 2018年第4期64卷 513-523页

作者： Thomas w. CRONIN Department of Biological Sciences University of Maryland Baltimore MD 21250 USA

Sensory drive, the concept that sensory systems primarily evolve under the influence of environmen tal features and that animal signals are evolutionarily shaped and tuned by these previously existing sensory systems, has been thoroughly studied regarding visual signals across many animals. Much of this work has focused on spectral aspects of vision and signals. Here, I review work on polarized light signals of animals and relate these to what is known of polarization visual systems, polarized light aspects of visual scenes, and polarizationrelated behavior （e.g., orientation, habitatfinding, contrast enhancement）. Other than the broad patterns of scattered polarized light in the sky, most po larization in both terrestrial and aquatic environments results from either reflection or scattering in the horizontal plane. with overhead illumination, horizontal features such as the surfaces of many leaves or of air： water interfaces reflect horizontal polarization, and water scatters horizontally polar ized light under most conditions. Several animal species have been demonstrated to use horizontally polarized light fields or features in critical aspects of their biology. Significantly, most biological sig nals are also horizontally polarized. Here, I present relevant polarizationrelated behavior and discuss the hypothesis that sensory drive has evolutionarily influenced the structure of polarization signals. The paper also considers the evolutionary origin of circular polarization vision and circularly polar ized signals. It appears that this class of signals did not evolve under the influence of sensory drive. The study of signals based on polarized light is becoming a mature field of research.

关键词： animal communication polarized light sensory drive vision visual signal

Evolving practice of demand-side management

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Journal of Modern Power Systems and Clean Energy 2017年第1期5卷 1-9页

作者： Clark w.GELLINGS Electric Power Research Institute Palo Alto CA USA Clark Gellings and Associates LLC Morgan Hill CA USA

The concept of demand-side management(DSM)was invented in the late 1970s along with the development of many of the frameworks in use to plan and implement it in the years immediately following. It was originally referred to as demand-side load management. It is generally defined as the planning and implementation of those activities designed to influence consumer use of electricity in ways that will result in changes in the utility’s load shape—i.e., changes in the time pattern and magnitude of a utility’s load. This paper describes the evolution it has undergone since its invention and some likely changes ahead. DSM largely originated in the U.S., but is practiced in various forms through the world today. This paper uses U.S. data as examples.

关键词： Demand-side management(DSM) Demandside load management Load management Energy efficiency Demand response(DR)