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Journal of Rare Earths 2018年第5期36卷 449-455页

作者： d. Suresh m. Yamashita T. Akai a National Institute for Advanced Industrial Science and Technology （AIST） Kansai Center 1-8-31 Midorigaoka lkeda Osaka 563-8577 Japan 6 Department of Chemistry School of Chemical and Biotechnology SASTRA Deemed University Thanjavur 613 401 India

divalent europium（Ⅱ）-doped mesoporous silicon oxy-nitride materials, as a novel type of nanoscopic photoluminescent material, are studied in which the optically active luminescent centers are isolated within the pores. Colorless and transparent blue emitting luminous Eu2＋-doped mesoporous silicon oxy-nitride materials were prepared from mesoporous silica via impregnation, nanocasting and nitrogen-assisted carbothermal reduction and nitridation method. The morphology and porosity of the silica remain unchanged during the synthesis process as revealed by SEm images and by nitrogen sorption studies. Photoluminescence studies reveal a strong blue emission band for Eu2＋ centered at 425 nm with a quantum efficiency of 47%. The luminescent intensity is greatly influenced by the amount of co-dopant, AI3＋ ions.

关键词： Blue luminescence divalent europium mesoporous silicon oxy-nitride Carbothermal reduction and nitridation(CRN) Rare earths

Experimental Study of High moisture Content Gas Flow Across a Cylinder at moderate Reynolds Numbers

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Tsinghua Science and Technology 2003年第5期8卷 598-604页

作者： d.m.Christopher 郭亮 department of Thermal Engineering

The Nusselt number for cross flow of a mixture of air and vapor over a cylinder was measured at moderate Reynolds numbers (30007000) for temperatures from 300℃ to 700℃ and for vapor mass fractions of 0.180.35. Results are also presented for a set of three cylinders aligned perpendicular to the flow for the same range of conditions. The effect of the vapor concentration and temperature on the convection coefficients was investigated to develop a modified Zhukauskas correlation. The results show that the Nusselt number increases as the moisture content increases and that the increase is more than could be accounted for by typical models for the property variations of mixtures. The exponent of the vapor concentration term in the modified correlation is 0.145 for the entire data set indicating the importance of the property variation due to the moisture content.

关键词： high moisture content cross flow convection coefficients heat exchangers

Large scale silver nanowires network fabricated by meV hydrogen (H＋) ion beam irradiation

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Chinese Physics B 2016年第4期25卷 268-273页

作者： Honey S Naseem S Ishaq A maaza m Bhatti m T Wan d Center of Excellence in Solid State Physics University of the Punjab Lahore Pakistan National Center for Physics Quaid-i-Azam University Islamabad 44000 Pakistan UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology College of Graduate Studies University of South Africa Muckleneuk ridge P. O. Box 392 Pretoria South Africa Nanosciences African Network (NANOAFNET) iThemba LABS National Research Foundation Old Faure road P. O. Box 722 Somerset West 7129 South Africa department of Physics Bahauddin Zakariya University Multan 60800 Pakistan School of materials Science and Engineering Shanghai University Shanghai 201900 China

A random two-dimensional large scale nano-network of silver nanowires （Ag-NWs） is fabricated by meV hydrogen （H＋） ion beam irradiation. Ag-NWs are irradiated under H＋ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H＋ ion beam-induced welding of Ag-NWs at intersecting positions. H＋ ion beam induced welding is confirmed by transmission electron microscopy （TEm） and scanning electron microscopy （SEm）. moreover, the structure of Ag NWs remains stable under H＋ ion beam, and networks are optically transparent. morphology also remains stable under H＋ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under meV H＋ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps： ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from meV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices.

关键词： Ag nanowires H+ ion irradiation nanowelding large scale nano-network optical properties

Earthquake response of asymmetric building with mR damper

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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 305-316页

作者： S.d.Bhart S.m.dumne m.K.Shrimali department of Civil Engineering malaviya National Institute of Technology Jaipur Govt.Poly.College Nashik Maharashtra India

Plan asymmetric buildings are very susceptible to earthquake induced damage due to lateral torsional coupling, and the corners of these systems suffer heavy damage during earthquakes. Therefore, it is important to investigate the seismic behavior of an asymmetric plan building with mR dampers. In this study, the effectiveness of mR damper-based control systems has been investigated for seismic hazard mitigation of a plan asymmetric building. Furthermore, the infl uence of the building parameters and damper command voltage on the control performance is examined through parametric study. The building parameters chosen are eccentricity ratio and frequency ratio. The results show that the mR damper-based control systems are effective for plan asymmetric systems.

关键词： torsional coupling plan asymmetric mR damper

Tuning red-green-white up-conversion color in nano NaYF_4:Er/Yb phosphor

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Journal of Rare Earths 2011年第12期29卷 1152-1156页

作者： A.Bednarkiewicz d.Wawrzynczyk m.Nyk m.Samo Institute of Low Temperature and Structure Research Polish Academy of Sciences(PAN) Wrocaw 50-422 Poland 2.Institute of Physical and Theoretical Chemistry Department of ChemistryWrocaw University of Technology

The possibility of ttming between red, green and broadband white color of up-conversion was demonstrated in thermally 450 ℃ treated Yb/Er co-doped nano NaYF4 phosphor. The color variability was studied by means of power dependence of luminescence, which exhibited unusual behavior. Large hysteresis, as well as discrepancy from a power law indicated the important role the increased heating played during the up-conversion in nano-sized materials.

关键词： lanthanides up-conversion white up-conversion emission nanphosphors rare earths

Comparative analysis of different static mixers performance by CFd technique:An innovative mixer

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Chinese Journal of Chemical Engineering 2020年第3期28卷 672-684页

作者： m.m.Haddadi S.H.Hosseini d.Rashtchian martin Olazar Chemical and Petroleum Engineering department Sharif University of TechnologyTehranIran department of Chemical Engineering.Ilam University llam 69315-516Iran department of Chemical Engineering University of the Basque Country(UPV/EHU)Sarriena s/nLeioaSpain

The flow and mixing behavior of two miscible liquids has been studied in an innovative static mixer by using CFd,with Reynolds numbers ranging from 20 to *** performance of the new mixer is compared with those of Kenics,SmX,and Komax static *** pressure drop ratio(Z-factor),coefficient of variation(CoV),and extensional efficiency(α)features have been used to evaluate power consumption,distributive mixing,and dispersive mixing performances,respectively,in all *** model is firstly validated based on experimental data measured for the pressure drop ratio and the coefficient of *** results are consistent with measured data and those obtained by available correlations in the *** new mixer shows a superior mixing performance compared to the other mixers.

关键词： CFd New static mixer Coefficient of variation Pressure drop ratio

The Influence of the Imperfectness of Contact Conditions on the Critical Velocity of the moving Load Acting in the Interior of the Cylinder Surrounded with Elastic medium

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Computers, materials & Continua 2018年第2期54卷 103-136页

作者： m.Ozisik m.A.mehdiyev S.d.Akbarov department of mathematical Engineering Yildiz Technical UniversityDavutpasa Campus34220Esenler-Istanbul-Turkey Institute of mathematics and mechanics of the National Academy of Sciences of Azerbaijan 37041BakuAzerbaijan department of mechanical Engineering Yildiz Technical UniversityYildiz Campus34349BesiktasIstanbulTurkey

The dynamics of the moving-with-constant-velocity internal pressure acting on the inner surface of the hollow circular cylinder surrounded by an infinite elastic medium is studied within the scope of the piecewise homogeneous body model by employing the exact field equations of the linear theory of *** is assumed that the internal pressure is point-located with respect to the cylinder axis and is axisymmetric in the circumferential ***,it is assumed that shear-spring type imperfect contact conditions on the interface between the cylinder and surrounding elastic medium are *** focus is on the influence of the mentioned imperfectness on the critical velocity of the moving load and this is the main contribution and difference of the present paper the related other *** other difference of the present work from the related other ones is the study of the response of the interface stresses to the load moving velocity,distribution of these stresses with respect to the axial coordinates and to the *** the same time,the present work contains detail analyses of the influence of problem parameters such as the ratio of modulus of elasticity,the ratio of the cylinder thickness to the cylinder radius,and the shear-spring type parameter which characterizes the degree of the contact imperfection on the values of the critical velocity and stress *** numerical results are presented and *** particular,it is established that the values of the critical velocity of the moving pressure decrease with the external radius of the cylinder under constant thickness of that.

关键词： moving internal pressure critical velocity circular hollow cylinder surrounded by elastic medium shear-spring type imperfection interface stresses

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert J.Thomas m.Brandon Westover Can Zhang department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(Ad) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of Ad is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

mechanical properties of 65mn chiral structure with three ligaments

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Acta mechanica Sinica 2019年第1期35卷 88-98,I0003页

作者： X.W.Su d.m.Zhu C.Zheng m.m.Tomovic School of Technology Beijing Forestry UniversityBeijing 100083China School of mechanical Engineering University of Science and Technology BeijingBeijing 100083 China Batten College of Engineering and Technology Old Dominion University Norfolk VA 23529 USA

Chiral honeycomb structures have been developed in recent years, showing excellent mechanical properties, including in-plane deformation and out-of-plane bearing and vibration isolation. In this study, the 65mn chiral structure with three ligaments was modeled and analyzed using the finite element (FE) method. The effects of the dimensionless ligament length and dimensionless ligament thickness on the in-plane equivalent elastic modulus, equivalent Poisson's ratio, and out-of-plane shear modulus were studied. The numerical results indicate that increase of the dimensionless ligament length leads to decrease of the equivalent elastic modulus and increase of the equivalePoisson's ratio, whereas the out-of-plane equivalent shear modulus decreases. The results also indicate that increase of the dimensionless ligament thickness leads to in crease of the equivalent elastic modulus, whereas the equivalent Poisson's ratio remains nearly unchanged and the out-of-plane equivalent shear modulus shows a linear in crease. The numerical results are verified by comparis on with published experime ntal data. These results will provide a reference for the application of chiral structures with three ligaments in the aerospace field.

关键词： Chiral structure with three ligaments mechanical properties Finite elemern method

Evaluating and mapping Grape Color Using Image-Based Phenotyping

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Plant Phenomics 2020年第1期2卷 95-105页

作者： A.N.Underhill C.d.Hirsch m.d.Clark department of Horticultural Science University of MinnesotaSt.PaulMNUSA department of Plant Pathology University of MinnesotaSt.PaulMNUSA

Grape berry color is an economically important trait that is controlled by two major genes influencing anthocyanin synthesis in the *** is often described qualitatively using six major categories;however,this is a subjective rating that often fails to describe variation within these six *** investigate minor genes influencing berry color,image analysis was used to quantify berry color using different color *** image analysis pipeline was developed and utilized to quantify color in a segregating hybrid wine grape population across two *** were collected from grape clusters immediately after harvest and segmented by color to determine the red,green,and blue(RGB);hue,saturation,and intensity(HSI);and lightness,red-green,and blue-yellow values(L∗a∗b∗)of *** analysis identified known major QTL for color on chromosome 2 along with several previously unreported smaller-effect QTL on chromosomes 1,5,6,7,10,15,18,and *** study demonstrated the ability of an image analysis phenotyping system to characterize berry color and to more effectively capture variability within a population and identify genetic regions of interest.

关键词： Image image mapping