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Activation of commercial Pt/C catalyst toward glucose electro-oxidation by irreversible Bi adsorption

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Journal of Energy Chemistry 2018年第5期27卷 1446-1452页

作者： Petri Kanninen tanja kallio Department of Chemistry and Material Science Aalto University P.O. Box 16100 00076 Aalto. Finland Applied Electrochemistry KTH-Royal Institute of Technology Teknikringen 42 10044 Stockholm Sweden

The effect of irreversibly adsorbed Bi on commercial Pt/C catalyst toward glucose electro-oxidation re- action （GOR） in different electrolytes （acidic, neutral, alkaline） is studied. Bi is successfully deposited on Pt/C from Bi3＋ containing acidic solution from 0 to 90% coverage degree. The stability of the Bi layer in acid and alkaline corresponded to previous studies and started to dissolve at 0.7 V and 0.8 V versus re- versible hydrogen electrode （RIIE）, respectively. However, in neutral phosphate buffer the layer showed remarkable stability to at least 1.2V versus RHE. Bi modification at low （20%） and high （80%） coverage showed the highest increase in the activity of Pt/C toward GOR by a factor up to 7 due to the increased poisoning resistance of the modified catalyst. The effect of poisoning was especially reduced at high Bi coverage （80%）, which shows that adsorbate blocked by Bi through the third-body effect is effective. Finally, with or without Bi modification GOR on PtIC was most active in alkaline conditions.

关键词： Glucose electro-oxidation Platinum Bismuth Catalyst poisoning Renewable resources

Machine Vision Based Measurement of Dynamic Contact Angles in Microchannel Flows

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Journal of Bionic Engineering 2008年第4期5卷 282-290页

作者： Valtteri Heiskanen Kalle Marjanen Pasi kallio Micro-and Nanosystems Research Group Department of Automation Science and Engineering Tampere University of Technology Measurements Based on Images Research Group Department of Automation Science and Engineering Tampere University of Technology

When characterizing flows in miniaturized channels, the determination of the dynamic contact angle is important. By measuring the dynamic contact angle, the flow properties of the flowing liquid and the effect of material properties on the flow can be characterized. A machine vision based system to measure the contact angle of front or rear menisci of a moving liquid plug is described in this article. In this research, transparent flow channels fabricated on thermoplastic polymer and sealed with an adhesive tape are used. The transparency of the channels enables image based monitoring and measurement of flow variables, including the dynamic contact angle. It is shown that the dynamic angle can be measured from a liquid flow in a channel using the image based measurement system. An image processing algorithm has been developed in a MATLAB environment. Images are taken using a CCD camera and the channels are illuminated using a custom made ring light. Two fitting methods, a circle and two parabolas, are experimented and the results are compared in the measurement of the dynamic contact angles.

关键词： digital image processing machine vision microfluidics microchannel flow dynamic contact angle image based measurement

Dreaming of the Great Rejuvenation of the Chinese Nation

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Fudan Journal of the Humanities and Social Sciences 2015年第4期8卷 521-532页

作者： Jyrki kallio The Finnish Institute of International Affairs Kruunuvuorenkatu 4 P.O. Box 400FI-00161 Helsinki Finland

Since the 18th Party Congress in 2012, there has been a steady stream of articles in the Chinese press discussing the ＂Chinese Dream＂ It is a dream of national rejuvenation, of China taking its rightful place in the world. There is no definition of national rejuvenation： nobody knows what it will look like. According to the Chinese leadership, the future models must be found from domestic soil and tradition. Traditionally, China was seen as a civilization at the center of All-Under- Heaven, a non-hegemonic power which relied to force only in order to protect itself against outside aggression. There are two upcoming centennials that serve as major milestones along the way to the rejuvenation, namely the 100th anniversary of the founding of the Communist Party in 2021, and the establishment of the People＇s Republic in 2049. The celebrations then will reveal if China follows this ancient tradition of benevolence, peacefulness and wisdom.

关键词： China - The Chinese dream International relations Soft power Confucianism Xi Jinping

Experimental and numerical study of pseudo-2D circulating fluidized beds

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Particuology 2016年第6期14卷 48-59页

作者： Adam Klimanek Wojciech Adamczyk Sirpa kallio Pawet Kozolub Gabriel Wecel Institute of Thermal Technology Silesian University of TechnologyKonarskiego 22 44-100 Gliwice Poland Technical Research Centre of Finland Ltd P.O. Box 1000 FI-02044 VTT Finland Amec Foster Wheeler Staszica 31 41-200 Sosnowiec Poland

We present experimental investigations and numerical simulations of a pseudo-2D riser. Experiments were performed for various airflow rates, particle types/diameters, and particle size distributions. Pres- sure distributions along the wall of the riser were measured, Additional measurements from a smaller pseudo-2D riser （kallio et al., 2009; Shah et al., 2012） were used to analyze horizontal solids volume fraction profiles. The experimental data were compared with simulation results carried out using an Euler-Euler approach, A mesh sensitivity study was conducted for numerical simulations and effects associated with simplifying real 3D geometry to a 2D model were examined. In addition, the effect of using an algebraic equation to represent the granular temperature versus a full partial differential equation also was examined for numerical simulations. Results showed small but significant near-wall sensitivity of the flow variables to mesh size. Substantial differences in mean pressure, solids distribution, and solid velocities were obtained, when 2D and 3D simulation results were compared. Finally, applying the simplified granular temperature equation for turbulent fluidization and for dilute-phase transport can lead to incorrect predictions in models,

关键词： Circulating fluidized bed Euler-Euler approachGas-solid flow Kinetic theory of granular flow Particle size distribution 2D vs 3D

CFD simulations of gas-solid flow in an industrial-scale circulating fluidized bed furnace using subgrid-scale drag models

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Particuology 2015年第1期13卷 66-75页

作者： Srujal Shah Kari My?h?nen Sirpa kallio Timo Hypp?nen Department of Energy Technology Lappeenranta University of Technology VTT Technical Research Centre of Finland

Mesoscale flow structures such as clusters and streamers of particles are characteristic features of gas-solid flow in fluidized beds. Numerical simulations of gas-solid flows for industrial-scale fluidized beds are often performed using the Eulerian description of phases. An accurate prediction of this type of flow structure using the Eulerian modeling approach requires a sufficiently fine mesh resolution. Because of the long computational time required when using fine meshes, simulations of industrial-sized units are usually conducted using coarse meshes, which cannot resolve the mesoscale flow structures. This leads to an overestimation of the gas-solid drag force and a false prediction of the flow field. For these cases, a cor- rection must be formulated for the gas-solid drag. We have simulated a large-scale circulating fluidized bed furnace using different gas-solid drag models and compared the model results with measurements.

关键词： Circulating fluidized bed Computational fluid dynamics Two-fluid model Drag correlation Modeling

Particle size distribution in CPFD modeling of gas-solid flows in a CFB riser

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Particuology 2015年第4期13卷 107-117页

作者： Qinggong Wang Timo Niemi Juho Peltola Sirpa kallio Hairui Yang Junfu Lu Lubin Weic Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal Engineering.Tsinghua University VTT Technical Research Centre of Finland School of Chemical and Environmental Engineering China University of Mining and Technology

A computational particle fluid dynamics （CPFD） numerical method to model gas-solid flows in a circulating fluidized bed （CFB） riser was used to assess the effects of particle size distribution （PSD） on solids distribution and flow. We investigated a binary PSD and a polydisperse PSD case. Our simulations were compared with measured solids concentrations and velocity profiles from experiments, as well as with a published Eulerian-Eulerian simulation. Overall flow patterns were similar for both simulation cases, as confirmed by experimental measurements. However, our fine-mesh CPFD simulations failed to predict a dense bottom region in the riser, as seen in other numerical studies. Above this bottom region, distri- butions of particle volume fraction and particle vertical velocity were consistent with our experiments, and the simulated average particle diameter decreased as a power function with riser height. Interactions between particles and wails also were successfully modeled, with accurate predictions for the lateral profiles of particle vertical velocity. It was easy to implement PSD into the CPFD numerical model, and it required fewer computational resources compared with other models, especially when particles with a polydisperse PSD were present in the heterogeneous flow.

关键词： Circulating fluidized bed riser Particle size distribution CPFD Numerical simulation

Introducing CHIPDRIVE MyKey: Computer Lock and Password Manager on a Smart Card-Secured USB Stick

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射频世界 2010年第2期 75-76页

作者： Johanna kallio Juhani Latvakoski

Santa Ana, Calif., March 30, 2010-Having trouble remembering all your passwords? Safely store your passwords, take them wherever you go, and lock up your computer whenever you leave with

关键词： Card Computer Lock and Password Manager on a Smart Card-Secured USB Stick USB

Ubiquitous Machine-to-Machine Service Networks

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射频世界 2010年第1期 76-77页

作者： Johanna kallio Juhani Latvakoski

In the near future,there will be many more embedded devices than there are mobile *** these devices are connected to the Internet,many novel kinds of ubiquitous service will be enabled.

关键词： than will more Ubiquitous Machine-to-Machine Service Networks Figure

Enhanced Map-Based Indoor Navigation System of a Humanoid Robot Using Ultrasound Measurements

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Intelligent Control and Automation 2012年第2期3卷 111-116页

作者： Iivari Back Jouko kallio Kari Makela Department of Biomedical Engineering Tampere University of TechnologySeinajokiFinland

During recent years, walking humanoid robots have gained popularity from wheeled vehicle robots in various assistive roles in human’s environment. Self-localization is a necessary requirement for the humanoid robots used in most of the assistive tasks. This is because the robots have to be able to locate themselves in their environment in order to accomplish their tasks. In addition, autonomous navigation of walking robots to the pre-defined destination is equally important mission, and therefore it is required that the robot knows its initiate location precisely. The indoor navigation is based on the map of the environment used by the robot. Assuming that the walking robot is capable of locating itself based on its initiate location and the distance walked from it, there are still factors that impair the map-based navigation. One of them is the robot’s limited ability to keep its direction when it is walking, which means that the robot is not able to walk directly from one point to another due to a stochastic error in walking direction. In this paper we present an algorithm for straightening the walking path using distance measurements by built-in sonar sensors of a NAO humanoid robot. The proposed algorithm enables the robot to walk directly from one point to another, which enables precise map-based indoor navigation.

关键词： Indoor Navigation Humanoid Robot Service Robot