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Improvement of drill Performance in Metal Cutting Using MoST Solid Lubricant Coatings

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材料热处理学报 2004年第05B期25卷 870-874页

作者： n.R. Thomas d.G. Teer S. Hickman Teer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UKTeer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UKTeer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UK

Coated tools are widely used in today’s metal cutting industries and have significantly improved machining productivity through reducing operation costs and time. This paper presents the results of a systematic study of the performance of HSS drills coated with CrTiAIn and drills with a top solid lubricant coating of MoST?. The tests were performed on a Haas vertical machining centre under wet and dry cutting conditions to machine through holes in medium carbon steel workpieces. The feed force and torque were recorded throughout some of the tests using a force dynamometer, while the tool wear was monitored and measured. It was found that MoST? coatings even under accelerated conditions improve the tool life significantly based on their unique properties and very low friction.

关键词：金属切割 MoST 固态润滑剂钻头

Microtubule as a Transmission Line for Ionic Currents

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Chinese Physics Letters 2009年第7期26卷 97-99页

作者： IliC d.I. SatariC M.V RaleviC n. Faculty of Technical Sciences University of Novi SadTrg D.Obradovica 621000 Novi SadSerbia

We establish a new model for ionic waves along microtubules based on polyelectrolyte features of cylindrical biopolymers. The nonlinear transmission line described by a nonlinear differential equation is obtained with stable kink solution pertinent to the shape of the front of accompanying potential. The localized ionic wave could be used to explain the behavior of microtubules as biomolecular transistors capable of amplifying electrical information in neurons.

关键词： Electronics and devices Biological physics

White matter hyperintensity progression is associated with incident probable dementia or mild cognitive impairment

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Stroke & Vascular neurology 2022年第4期7卷 364-366页

作者： Adam de Havenon Kevin n Sheth Sharon d Yeatts Tanya n Turan Shyam Prabhakaran neurology Yale UniversityNew HavenConnecticutUSA Public Health Sciences MUSCCharlestonSouth CarolinaUSA neurology MUSCCharlestonSouth CarolinaUSA neurology University of Chicago Pritzker School of MedicineChicagoIllinoisUSA

Background White matter hyperintensity(WMH)on brain MRI is associated with developing dementia or mild cognitive impairment(MCI),but WMH progression over time has not been fully investigated as an independent risk *** We performed a post hoc analysis of the Systolic Blood Pressure Intervention Trial-Memory and Cognition in decreased Hypertension(SPRInT MInd)*** primary outcome was incident probable dementia or MCI(dementia/MCI)before the follow-up MRI at 48 months from *** primary predictor was WMH progression,defined as the Z score difference between the follow-up and baseline WMH *** secondary predictor was a binary WMH progression threshold(≥1.4 mL vsng the 433 included patients,33(7.6%)developed dementia/*** were 156(36.0%)patients who met the WMH progression threshold of≥1.4 mL,in whom the rate of dementia/MCI was 12.8%(20/156)vs 4.7%(13/277)of patients withn(p=0.002).In multivariable logistic regression,the Z score of WMH progression was associated with dementia/MCI(OR 1.51,95%CI 1.12 to 2.04,p=0.007)as was the WMH progression threshold of≥1.4 mL(OR 2.89,95%CI 1.23 to 6.81,p=0.015).Conclusions In this post hoc analysis of SPRInT MInd,WMH progression over 48 months was associated with the development of probable dementia or MCI.

关键词： impairment Blood incident

d614G and SARS-CoV-2 replication fitness

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Signal Transduction and Targeted Therapy 2021年第4期6卷 1073-1074页

作者： Kathleen d.Engelman Alan n.Engelman MassBiologics University of Massachusetts Medical SchoolBostonMAUSA department of Cancer Immunology and Virology Dana-Farber Cancer InstituteBostonMAUSA department of Medicine Harvard Medical SchoolBostonMAUSA

Molecular determinants of SARS-CoV-2 replication fitness and sensitivity to neutralization via the humoral immune response critically inform efforts to combat the COVId-19 *** published recently by Plante et *** natur... 详细信息

关键词： al. processes. d61

SULPHOnATEd POLY ETHER ETHER KETOnE/POLYVInYL ALCOHOL/PHOSPHOTUnGSTIC ACId COMPOSITE MEMBRAnES FOR PEM FUEL CELLS

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Chinese Journal of Polymer Science 2009年第2期27卷 157-164页

作者： S.Guhan n.Arun Kumar d.Sangeetha department of Chemistry Anna University

Composite membranes with polyvinyl alcohol (PVA),sulphonated poly ether ether ketone (SPEEK) and phosphotungstic acid (PWA) were prepared using solvent casting *** proton conductivities of such membranes were found to be in the order of 10^(-3) S/cm in the fully hydrated condition at room temperature as measured by impedance *** crystalline properties were studied by X-ray diffraction *** thermal properties were determined by TGA and dSC *** tensile strength and perce...

关键词： PVA SPEEK PWA Conductivity Composite membranes.

Optical high-resolution spectroscopic study of Tm^(3+) crystal-field levels in LiLuF_4

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Journal of Rare Earths 2009年第4期27卷 624-626页

作者： d.S.Pytalev S.A.Klimin M.n.Popova Institute of Spectroscopy Russian Academy of Sciences 5 Fizicheskaya St. Troitsk Moscow region 142190 Russia

We report on the fast high-resohition study of LiLuF4：Tm3＋. The accurate energy level scheme of Tm3＋ in the LiLuF4 matrix was obtained for the 3H6.5.4, 3F4.3.2, and ^1G4 multiplets. It was shown that electric-dipol... 详细信息

关键词： Fourier-transform spectroscopy Tm^3+ crystal-field levels LiLuF4 rare earths

discussions on the correspondence of dissipative particle dynamics and Langevin dynamics at small scales

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Applied Mathematics and Mechanics(English Edition) 2018年第1期39卷 31-46页

作者： d. AZARnYKH S. LITVInOV X. BIAn n.A. AdAMS department of Mechanical Engineering Technical University of Munich Munchen 85748 Germany Eidgen Sssische Technische Hochschule Zfirich Zurich CH-8092 Switzerland

We investigate the behavior of dissipative particle dynamics （dPd） within different scaling regimes by numerical simulations. The paper extends earlier analytical findings of Ripoll, M., Ernst, M. H., and Espafiol, P. （Large scale and mesoscopic hy- drodynamics for dissipative particle dynamics. Journal of Chemical Physics, 115（15）, 7271-7281 （2001）） by evaluation of numerical data for the particle and collective scaling regimes and the four different subregimes. dPd simulations are performed for a range of dynamic overlapping parameters. Based on analyses of the current auto-correlation functions （CACFs）, we demonstrate that within the particle regime at scales smaller than its force cut-off radius, dPd follows Langevin dynamics. For the collective regime, we show that the small-scale behavior of dPd differs from Langevin dynamics. For the wavenumber-dependent effective shear viscosity, universal scaling regimes are observed in the microscopic and mesoscopic wavenumber ranges over the considered range of dynamic overlapping parameters.

关键词： dissipative particle dynamics (dPd) mesoscopic dynamics fluctuating hydrodynamics

nonlinear stability of functionally graded material(FGM)sandwich cylindrical shells reinforced by FGM stiffeners in thermal environment

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Applied Mathematics and Mechanics(English Edition) 2017年第5期38卷 647-670页

作者： d.V.dUnG n.T.nGA L.K.HOA Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam Faculty of Basic Science Military Logistic AcademyHanoi 100000Vietnam

In this paper, donnell＇s shell theory and smeared stiffeners technique are improved to analyze the postbuckling and buckling behaviors of circular cylindrical shells of stiffened thin functionally graded material （FGM） sandwich under an axial loading on elastic foundations, and the shells are considered in a thermal environment. The shells are stiffened by FGM rings and stringers. A general sigmoid law and a general power law are proposed. Thermal elements of the shells and reinforcement stiffeners are considered. Explicit expressions to find critical loads and postbuckling load-deflection curves are obtained by applying the Galerkin method and choosing the three-term approximate solution of deflection. numerical results show various effects of temperature, elastic foundation, stiffeners, material and geometrical properties, and the ratio between face sheet thickness and total thickness on the nonlinear behavior of shells.

关键词： functionally graded material (FGM) stiffened cylindrical shell sandwich,thermal environment

Seismic response of bridge pier on rigid caisson foundation in soil stratum

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Earthquake Engineering and Engineering Vibration 2008年第1期7卷 33-43页

作者： C. Tsigginos n. Gerolymos d. Assimaki G. Gazetas national Technical University of Athens Greece Civil Engineer Civil Engineering National Technical University of Athens Greece Lecturer Civil Engineering Georgia Institute of Technology Atlanta USA Assistant Professor Civil Engineering National Technical University of Athens Greece Professor

An analytical method to study the seismic response of a bridge pier supported on a rigid caisson foundation embedded in a deep soil stratum underlain by a homogeneous half space is developed. The method reproduces the kinematic and inertial responses, using translational and rotational distributed Winkler springs and dashpots to simulate the soil-caisson interaction. Closed-form solutions are given in the frequency domain for vertical harmonic S-wave excitation. Comparison with results from finite element （FE） analysis and other available solutions demonstrates the reliability of the model. Results from parametric studies are given for the kinematic and inertial responses. The modification of the fundamental period and damping ratio of the bridge due to soil-structure interaction is graphically illustrated.

关键词： caisson embedded foundations kinematic response inertial response Winkler model effective period effective damping