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Fabrication of chitosan/silica hybrid coating on AZ31 Mg alloy for orthopaedic applications

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journal of Magnesium and Alloys 2023年第2期11卷 614-628页

作者： M.Kalaiyarasan S.Pugalmani n.rajendran Department of Chemistry CEG CampusAnna UniversityChennai600025Tamil NaduIndia Department of Orthodontics Saveetha Dental College and HospitalsSaveetha Institute of Medical and Technical ScienceSaveetha UniversityChennai-600077India

Biocompatible conversion of chitosan and chitosan/silica hybrid coating were prepared to enhance the biocompatibility and corrosion resistance of biodegradable AZ31 Mg alloy. The coatings were optimized and analysed with potentiodynamic polarization, SEM, ATr-Ir and XPS studies. Potentiodynamic polarization studies, revealed that the coatings exhibited high corrosion resistance. The surface morphology of the Ch-3/Si coating showed small globular rough structure. The presence of functional groups was confirmed by ATr-Ir. For a better understanding of chitosan/silica hybrid coating, the chemical states were examined by XPS studies. The in-vitro bioactivity of the coated samples was evaluated in Earle’s solution, which formed a dense layer of coral-like structure and calcium-deficient apatite with less stoichiometric ratio than the hydroxyapatite. In-vitro cell culture studies exhibited a good cell proliferation rate and the fabricated Ch-3/Si coating was found to be non-hemolytic. The bacterial studies proved that Ch-3/Si coating possessed inherent antibacterial activity.

关键词： AZ31 Mg alloy Chitosan/silica Hemocompatibility MTT assay and antibacterial Studies

MODELInG OF MICrOMAnIPULATIOn rOBOT In VIrTUAL EnVIrOnMEnT

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Acta Metallurgica Sinica(English Letters) 2004年第2期17卷 194-198页

作者： F.S.Tan L.n.Sun W.B.rong j.Zhu robotic research Institute,Harbin Institute of Technology,Harbin 150001,China robotic research Institute Harbin Institute of Technology Harbin 150001 China

Micromanipulation has been recognized to be very difficult due to the inefficiency oftraditional micromanipulation methods. The paper present a general framework formicromanipulation robot based on virtual reality technology. The significance of in-troducing virtual reality into micromanipulation is analyzed, and the current researchin this field is reviewed. Based on this, we propose a micromanipulation system thatintegrates virtual environment with vision feedback and force feedback. The systemrealizes vision close-loop control and force close-loop control to enhance the perfor-mance of micromanipulation device. A graphics modelling method is proposed for amicroassembly task. Hardware and software implementation is described and discus-sion about the research is presented.

关键词： micromaniqulation virtual reality vision feedback force feedback microassembly

Scheduling multi-tenant cloud workflow tasks with resource reliability

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Science China(Information Sciences) 2022年第9期65卷 127-144页

作者： Xiaoping LI Dongyuan PAn Yadi WAnG rubén rUIZ School of Computer Science and Engineering Southeast University Institute of Data and Knowledge Engineering School of Computer and Information EngineeringHenan University Grupo de Sistemas de Optimización Aplicada Universitat Politècnica de València

resource reliability is crucial in scheduling workflow instances for different tenants. Both cloud resource reliability and precedence constraints in workflows bring about great challenges for these kinds of scheduling problems. In this paper, we construct a hybrid resource reliability model which is adaptively evaluated in every time window. The objective is to optimize the QoS(quality of service) for tenants which is measured by the introduced AISE(all instance success entropy) index. A scheduling algorithmic framework is proposed for the studied workflows which consider cloud resource reliability. Deadline and budget division(BD) methods are presented to divide deadlines and budgets of instances into those of tasks. A tenant sequence method is developed to determine the order of tenants. A task allocation strategy is investigated to schedule tasks that are ready to appropriate available resources. Parameters and algorithm component candidates are statistically calibrated over a comprehensive set of random instances using the analysis of variance technique. The performance of the proposed algorithm is also evaluated in practical instances.

关键词： multi-tenancy resource reliability cloud computing scheduling

Electric-jet Assisted Layer-by-Layer Deposition of Gold nanoparticles to Prepare Conducting Tracks

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natural Science 2009年第2期1卷 142-150页

作者： S. r. Samarasinghe Isabel Pastoriza-Santos M. j. Edirisinghe M. j. reece Luis Liz-Marzán M. r. nangrejo Z. Ahmad 不详

A suspension of 15nm diameter gold nanoparti-cles has been deposited along a line on a silicon substrate with the assistance of a jet generated in an electric field. In order to control the evaporation of the solvent used to suspend the gold nanoparticles, a heating device was used to change the substrate temperature. Layer-by- layer deposition enabled the direct writing of gold tracks having an electrical resistivity of 1.8 × 10-7 Ωm, only about an order of magnitude above the electrical resistivity of bulk gold.

关键词： Gold Electrohydrodynamic jet Direct Write Track Electrical Conductivity

Effect of the high-power electromagnetic pulses on the reactivity of the coal-water slurry in hot environment

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Chinese journal of Chemical Engineering 2020年第12期28卷 3145-3151页

作者： M.V.Belonogov r.I.Taburchinov r.I.Egorov national research Tomsk Polytechnic University TomskRussian Federation

An effect of the high-power electromagnetic pulses onto the droplet of coal-water slurry inside the furnace was *** contrary to the previously investigated laser-induced fuel atomization that occurs at the room temperature,the pre-heated(to 400 K)slurry becomes dry enough to prevent the explosion-like steam ***,fuel does not atomize and the ignition does not ***,the absorption of several laser pulses leads to evident sintering of irradiated surface with following increase of the ignition delay time for up to 24%.Variation of the pulse energy in range 48-118 mj(corresponding intensity up to 2.4 j·cm^-2)leads to certain variation of the increase of ignition *** strong pulsed overheating of the coal water slurry which does not initiate the fine atomization of the fuel generally makes its ignition longer.

关键词： Waste-derived fuels Coal-water slurry Auto-ignition Ignition delay time High-power laser pulse

Detection of thermonuclear X-ray bursts and dips from the X-ray binary 4U 1323-62 with AstroSat/LAXPC

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research in Astronomy and Astrophysics 2020年第6期20卷 281-292页

作者： Yashpal Bhulla jayashree roy S.n.A.jaaffrey Pacific Academy of Higher Education and research University Udaipur-313003India Inter-University Center for Astronomy and Astrophysics Pune-411007India

Using data from the Large Area X-ray Proportional Counter(LAXPC)on the AstroSat satellite,we observed Type-1 thermonuclear X-ray bursts from the low mass X-ray binary neutron star 4 U *** of 4 U 1323-62 that were carried out during the performance verification phase of the AstroSat satellite indicated six thermonuclear X-ray bursts in a total effective exposure of^49.5 ks for about two consecutive *** time of the detected thermonuclear bursts is in accordance with the orbital period of the source,~9400 ***,the light curve of 4 U 1323-62 revealed the presence of two *** present the results from time-resolved spectroscopy performed during all of the six X-ray bursts and also report the detection of a known low frequency quasi-periodic oscillation(LFQPO)at^1 Hz from the ***,any evidence of kilohertz QPO was not *** have shown the burst profile at different energy *** a distance of 10 kpc,we observed a mean flux of^1.8×10^-9 erg cm^2 s^-*** radius of the blackbody is found to be highly consistent with the blackbody temperature and the blackbody flux of the bursts.

关键词： accretion-accretion disc-stars neutron star-X-rays binaries-X-rays thermonuclear bursts-individual 4U 1323–62

Trees of Panama: A complete checklist with every geographic range

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Forest Ecosystems 2020年第3期7卷 526-538页

作者： richard Condit Salomón Aguilar rolando Pérez Morton Arboretum 4100 Illinois Rte.53Lisle60532ILUSA Smithsonian Tropical research Institute Panama CityPanama

Background Central America is one of the most diverse floristic provinces in the world,but comprehensive plant lists for the region are incomplete and need frequent *** geographic ranges of individual species are seldom *** detailed forest inventory plots of Panama thus lack a global geographic *** order to provide one,we assembled a thoroughly vetted checklist of all tree species of Panama,along with an estimate of each one’s range size based on published specimen *** 1)Panama has 3043 tree species in 141 families and 752 genera;57.6%were≥10 m tall and 16.9%were 3-5 m tall.2)The widest ranges were>1.5×107 km2,covering the entire neotropics and reaching>30∘latitude;12.4%of the species had ranges exceeding 107 *** median range was 6.9×105 km2.3)At the other extreme,16.2%of the species had a rangeriterion suggesting endangered status.4)range size increased with a tree species’height and varied significantly among families.5)Tree census plots,where we mapped and measured all individuals,captured 27.5%of the tree species,but a biased selection relative to range size;only 4.5%of the species in plots had rangesr checklist of the trees of Panama,based on rigorous criteria aimed at matching plot censuses,is 20%larger than *** recording species’maximum heights,we allow comparisons with other regions based on matching definitions,and the range sizes provide a quantitative basis for assessing extinction *** next goal is to merge population density from plot censuses to add rigor to predictions of extinction risk of poorly-studied tropical tree species.

关键词： red Trees of Panama A complete checklist with every geographic range

Characteristics of urban ozone level in Hong kong

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journal of Environmental Sciences 2001年第1期13卷 1-7页

作者： D.Y.C.LEUnG D.n.ZHAnG Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina research Institute of Environmental Engineering East China University of Science and TechnologyShanghai 200237China

The long term trend of ozone level in Hong Kong has been investigated. One of the characteristics of ozone level in Hong Kong is the existence of autumn maximum and summer minimum. Observations of the diurnal variation of ozone level have been made in different area categories. There are early morning peak and afternoon peak occurred in the diurnal variation, which are different from some metropolitans where only an afternoon peak is observed. A negative correlation coefficient was found between monthly ozone level with nitric oxide level. On the contrary, there is a positive correlation between ozone and nitrogen dioxide. The positive correlation coefficient between nitric oxide and nitrogen dioxide shows that the total amount of nitric oxide emitted from a series of moving and fixed sources greatly exceeded the stoichiometric amount of ozone formed from chemical reactions of precursors and long distance transportation.

关键词： ozone urban air pollution Hong kong China

F4-TCnQ concentration dependence of the current voltage characteristics in the Au/P3HT:PCBM:F4-TCnQ/n-Si(MPS) Schottky barrier diode

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Chinese Physics B 2014年第11期23卷 512-522页

作者： E.Yaglioglu O.Tzn Ozmen Department of Physics Faculty of Arts and Sciences Dzce University

In this study, we investigate some main electrical parameters of the gold/poly（3-hexylthiophene）：[6,6]-phenyl C61 bu- tyric acid methyl ester：2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane/n-type silicon （Au/P3HT：PCBM：F4-TCnQ/n- Si） metal-polymer-semiconductor （MPS） Schottky barrier diode （SBD） in terms of the effects of F4-TCnQ concentration （0%, 1%, and 2%）. F4-TCnQ-doped P3HT：PCBM is fabricated to figure out the p-type doping effect on the device per- formance. The main electrical parameters, such as ideality factor （n）, barrier height （ФB0）, series resistance （rs）, shunt resistance （rsh）, and density of interface states （nss） are determined from the forward and reverse bias current-voltage （l-V） characteristics in the dark and at room temperature. The values of n, rs, ФB0, and nss are significantly reduced by using the 1% F4-TCnQ doping in P3HT：PCBM：F4-TCnQ organic blend layer, additionally, the carrier mobility and current are increased by the soft （1%） doping. The most ideal values of electrical parameters are obtained for 1% F4-TCnQ used diode. On the other hand, the carrier mobility and current for the hard doping （2%） become far away from the ideal diode values due to the unbalanced generation of holes/electrons and doping-induced disproportion when compared with 1% F4-TCnQ doping. These results show that the electrical properties of MPS SBDs strongly depend on the F4-TCnQ doping and doping concentration of interfacial P3HT：PCBM：F4-TCnQ organic layer. Moreover, the soft F4-TCnQ dop- ing concentration （1%） in P3HT：PCBM：F4-TCnQ organic layer significantly improves the electrical characteristics of the Au/P3HT：PCBM：F4-TCnQ/n-Si （MPS） SBDs which enables the fabricating of high-quality electronic and optoelectronic devices.

关键词： P3HT:PCBM:F4-TCnQ interfacial organic layer F4-TCnQ doping concentration Schottky bar-rier diodes I-V characteristics