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Loaded Rubber-Like Materials Subjected to Small-Amplitude Vibrations

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Chinese Journal of Polymer Science 2014年第5期32卷 620-632页

作者： T.beda J.b.Casimir K.e.Atcholi Y.Chevalier Industrial and Mechanical engineering Department Ecole Nationale Supérieure Polytechnique (ENSP) Département de Physique Faculté des Sciences Université de NGaoundéré Laboratoire d’Ingénierie des Structures Mécanique et des Matériaux (LISMMA) SUPMECA de Paris Institut de Recherche sur les Transports l’Energie et la Société (IRTES EA7274) Laboratoire Systèmes et Transport (SeT EA 3317) Université de Technologie de Belfort-Montbéliard (UTBM)

This paper proposes a constitutive law and a method for characterizing highly preloaded viscoelastic materials subjected to linear （small-amplitude） vibrations. A multiplicative non-separable variables law has been suggested to model the behavior that depends on both stretch and time/frequency. This approach allows splitting the intricate combined test performed simultaneously on both stretch and frequency, generally in a limited experimental domain up to 100 Hz, into two independent tests. Thus, on one hand, the dynamic complex modulus dependent on frequency alone is evaluated on the basis of vibration tests in a large experimental domain up to 100 kHz. On the other hand, energetic parameters are determined from a quasi-static hyperelastic tensile test. The complex modulus, dependent on both stretch and frequency, is then deduced from the results acquired from uncoupled investigations. This work shows that, in extension, the elastic modulus increases with increasing stretch, and the loss factor decreases with increasing stretch; while, in compression, around the material undeformed state, the modulus increases as the stretch increases till a certain value of compression stretch （upturn point depending on material characteristics）, and then the modulus decreases as the stretch increases. Globally, preload rigidifies materials but reduces their damping property. These results closely match a well-known observation in solid mechanics.

关键词： elastomers Viscoelasticity Hyperelasticity Vibrations Modeling Characterization Combined modulus.

Thermoluminescence Kinetic Parameters of TLD-600 and TLD-700 after 252Cf Neutron+Gamma and 90Sr-90Y beta Radiations

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Chinese Physics Letters 2017年第1期34卷 120-124页

作者： S.Iflazoglu V.e.Kafadar b.Yazici A.N.Yazici University of Gaziantep Department of Engineering PhysicsGaziantep 27310Turkey

The thermoluminescent(TL) properties such as glow curve structure, relative thermoluminescence sensitivity,dose response linearity of lithium fluoride thermoluminescent dosimeters 6 LiF:Ti,Mg(TLD-600) and 7 LiF:Ti,Mg(TLD-700) are investigated after irradiationCf neutron+gamma andSr-Y beta sources at room temperature and then the obtained results are compared. The kinetic parameters, namely the order of kinetics b,activation energy ea and the frequency factor s,are calculated using the computerized glow curve deconvolution(CGCD) program. The effect of heating rate on the glow curves of dosimeters is also investigated. The maximum TL peak intensities and the total area under the glow curves decrease with the increasing heating rate. There is no agreement with the kinetic parameters calculated by the CGCD program for both radiation sources.

关键词： TLD Cf Neutron+Gamma and Sr

Transcriptome and Proteome expressions Involved in Insulin Resistance in Muscle and Activated T-Lymphocytes of Patients with Type 2 Diabetes

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Genomics, Proteomics & bioinformatics 2007年第3期5卷 216-235页

作者： Frankie b.Stentz Abbas e.Kitabchi Division of endocrinology Diabetes and MetabolismDepartment of MedicineThe University of Tennessee Health Science CenterMemphisTN 38163USA.

We analyzed the genes expressed （transcriptomes） and the proteins translated （pro- teomes） in muscle tissues and activated CD4^＋ and CD8^＋ T-lymphocytes （T-cells） of five Type 2 diabetes （T2DM） subjects using Affymetrix microarrays and mass spectrometry, and compared them with matched non-diabetic controls. Gene expressions of insulin receptor （INSR）, vitamin D receptor, insulin degrading enzyme, Akt, insulin receptor substrate-1 （IRS-1）, IRS-2, glucose transporter 4 （GLUT4）, and enzymes of the glycolytic pathway were decreased at least 50% in T2DM than in controls. However, there was greater than two-fold gene upregulation of plasma cell glycoprotein-1, tumor necrosis factor a （TNFα）, and gluconeogenic enzymes in T2DM than in controls. The gene silencing for INSR or TNFα resulted in the inhibition or stimulation of GLUT4, respectively. Proteome profiles corresponding to molecular weights of the above translated transcriptomes showed different patterns of changes between T2DM and controls. Meanwhile, changes in transcriptomes and proteomes between muscle and activated T-cells of T2DM were comparable. Activated T-cells, analogous to muscle cells, expressed insulin signaling and glucose metabolism genes and gene products. In conclusion, T-cells and muscle in T2DM exhibited differences in expression of certain genes and gene products relative to non-diabetic controls. These alterations in transcriptomes and proteomes in T2DM may be involved in insulin resistance.

关键词： genomics proteomics T-lymphocytes activation muscle Type 2 diabetes

Geographical location affects size and materials used in the construction of european Pied Flycatcher(Ficedula hypoleuca) nests

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Avian Research 2019年第2期10卷 111-125页

作者： Kevin b.briggs Lucia e.biddle D.Charles Deeming Joseph banks Laboratories School of Life SciencesUniversity of Lincoln

background: Nest construction is a key element of avian reproductive behaviour and the result is often a complex structure that is used for incubation of eggs, which represents an extended phenotype. It is known that nest construction is a plastic behaviour but the extent to which plasticity is observed in a single species with a wide geographical distribution is largely unknown. This study sought to better understand variation in nest size and composition across a very wide geographical area. The hypothesis suggested that location would affect size but not composition of nests of the european Pied Flycatcher (Ficedula hypoleuca). Methods: Nests and reproductive data were collected from seventeen study sites, spread over 6° of latitude and 3.3° of longitude on the island of Great britain. Dimensions of nests were measured before they were deconstructed to determine the masses and types materials used in the outer nest and the cup lining. Results: Geographical variation was observed in base thickness of nests but not many other dimensions. Nests varied in composition but were mainly made of leaf, moss, bark, grass, root and fern. Moss was used more to the north and east of the study area compared with more leaf mass towards the south and west. The species of leaf and bark used in the nests varied between geographical locations. Additionally, the use of leaves or bark from a particular tree species did not reflect the incidence of the tree species in the immediate territory. Conclusions: This study showed that nest composition was affected by geographical location over a wide area. Variation between nests at each location was high and so it was concluded that differences in nest composition reflect individual selection of materials but evidence is such that it remains unclear whether this is deliberate to fulfil a specific role in the nest, or simply opportunistic with birds simply picking up materials with the appropriate characteristics as they find them outside the

关键词： breeding success Ficedula hypoleuca Latitude Longitude Nest composition Nest size Nest structure

Development and characterization of a microfluidic glucose sensing system based on an enzymatic microreactor and chemiluminescence detection

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Science China Chemistry 2012年第4期55卷 515-523页

作者： MOON b.-U. de VRIeS M.G. WeSTeRINK b.H.C. VeRPOORTe e. biomonitoring and Sensoring Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands Pharmaceutical Analysis Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands brains-on-Line PO Box 4030 9713AV Groningen The Netherlands

Chemiluminescence detection was developed as an alternative to amperometric detection for glucose analysis in a portable, microfluidicsbased continuous glucose monitoring system. Amperometric detection allows easy determination of hydrogen peroxide, a product of the glucose oxidasecatalyzed reaction of glucose with oxygen, by oxidation at a microelectrode. However, （micro）electrodes in direct contact with physiological sample are subject to electrode fouling, which leads to signal drift, decreased reproducibility and shortened detector lifetimes. Moreover, there are a few species present in the body （e.g. ascorbic acid, uric acid） which can undergo oxidation at the same applied potential as hydrogen peroxide. These species can thus inter- fere with the glucose measurement, reducing detection specificity. The rationale for exploring chemiluminescence as opposed to amperometric detection is thus to attempt to improve the lifetime and reproducibility of glucose analysis for monitoring purposes, while reducing interference caused by other chemicals in the body. The study reported here represents a first step in this direction, namely the realization of a microfluidic device with integrated silicon photodiode for chemiluminescence detection of glucose. This microflow device uses a chaotic mixing approach to perform enzymatic conversion of glucose, followed by reaction of the hydrogen peroxide produced with luminol to produce light at 425 nm. The chemil reaction is catalyzed by horseradish peroxidase in the presence of iodophenol. The performance of the fabricated chip was characterized to establish optimal reaction conditions with respect to sample and reagent flow rates, pH, and concentrations. A linear calibra- tion curve was obtained for current response as a function of glucose concentration in the clinically relevant range between 2 and 10 mM, with a sensitivity of 39 pA/mM （R = 0.9963, one device, n = 3） and a limit of detection of 230 ktM （S/N - 3）.

关键词： microfluidic chip – glucose sensing system – enzymatic microreactor – chemiluminescence – chaotic mixing

Review analysis on cloud computing based smart grid technology in the oil pipeline sensor network system

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Petroleum Research 2021年第1期6卷 77-90页

作者： e.b.Priyanka S.Thangavel Xiao-Zhi Gao Department of Mechatronics engineering Kongu Engineering CollegePerunduraiErodeIndia School of Computing University of Eastern FinlandFinland

Natural resources plays efficient contribution in the human world in the way of consuming energy resources for the daily life *** main concerns rely on the transporting oil from refining to the consumer usages through different *** the transportation passages,its performances are calibrated in the robust manner through sensor network communication and the periodical pigging inspection on the pipeline *** chapter enumerates about the layout of oil pipeline system and its sensor measurement and instrumentation deliberately placed on the long run *** evolution of smart grid application enhances this oil transportation in a much corporate band by accumulatively orienting the sensor network in the utilization of power ***,through the wireless communication associated with the smart grid,the pigging inspection gauges are exploited in the desired geographical area with better power *** research on communication technologies in SG is briefly overviewed with the main focus on Cloud computing *** this paper,the Smart Grid architecture and its applications are focused on entire oil pipeline from inlet to distribution substations *** Cloud Computing architecture is explained ***,Cloud Computing for Smart Grid applications are also introduced in terms of efficiency,security and *** platforms technical and security protocols are ***,the inspection of oil pipeline system by receiving sensor data of smart pigs incorporated with the cloud computing technique associated with smart grid application is elaborated with its SCADA hierarchical ***,simulation analysis of wireless sensor nodes with Flexmeter platform for power monitoring over smart pig case scenario is also presented with its layer-wise characterization.

关键词： Oil pipelines Smart grid Pigging Cloud computing Sensor

Magnetic properties of Fe_(3(1-x))Cr_(3x)C alloys

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 314-316页

作者： Feng-qi Zhao O. Tegus b. Fuquan e. brück Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials College of Physics and Electron Information Inner Mongolia Normal University Hohhot 010022 China Van der Waals-Zeeman Instituut Universiteit van Amsterdam Valckenierstraat 65 1018XE Amsterdam Netherlands

The magnetic properties of Fe3（1-x）Cr3xC alloys with x=0.05, 0.1, 0.15, and 0.2, which crystallize in the cementite Fe3C-type structure with space group Pnma, were investigated by means of magnetization measurements. These alloys show temperature-induced second-order magnetic phase transitions. The Curie temperature （Tc） of these alloys decreases with increasing x. The isothermal magnetic-entropy changes of these alloys were derived from the magnetic isotherms measured with increasing temperature and increasing field. The maximum values of the magnetic-entropy change are about 0.9 and 3.6 J·kg^-1·K^-1 at Tc =360 K for x = 0.05 in a magnetic field change from 0 to 1 T and 0 to 5 T, respectively.

关键词： magnetic properties magnetocaloric effect magnetic-entropy change magnetic refrigeration

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现代英国文学简介

Tree regeneration in gap-understory mosaics in a subtropical Shorea robusta(Sal) forest

作者： e.b.·布什 e.b.·booz

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Journal of Forestry Research 2019年第6期30卷 2061-2068页

作者： L.N.Sharma K.b.Shrestha I.e.Maren Forest Action Nepal GPO-12207 LalitpurNepal Department of biological Sciences University of BergenThormoensgate 53B5007 BergenNorway

Spatial variation in tree-regeneration density is attributed to the specialization of tree species to light availability for germination and *** availability,in turn,varies across the gap-understorey *** gaps provide an important habitat for the regeneration of tree species that would otherwise be suppressed in the *** subtropical forests,there is still a knowledge-gap relating to how canopy disturbances influence tree-regeneration patterns at local scale,and if they disproportionately favor regeneration of certain *** aim to analyze whether canopy gaps promote tree regeneration,and tree species are specialized to gaps or understory for germination and *** sampled vegetation in 128 plots(0.01 ha),equally distributed in gaps and below canopy,in two subtropical Shorea robusta Gaertn.(Sal)forests in Nepal,recording the number of tree seedlings and saplings in each *** compared the regeneration density of seedlings and saplings separately between gaps and the *** mean densities of seedlings and saplings were higher in the gaps at both sites;although there was no difference in the seedling density of the majority of the species between the *** species were confined to either gap or understorey at the seedling *** conclude that gaps are not critical for the germination of tree species in Sal forests but these are an important habitat for enabling seedlings to survive into *** classification of trees into regeneration guilds mainly based on germination does not apply to the majority of tree species in subtropical Sal *** results reaffirm that gap creation promotes tree regeneration by favouring seedling survival and growth and can influence forest management for conservation,as well as for plantations.

关键词： Canopy-gap Density Regeneration Saplings Seedlings Shade tolerance