Ubimedia based on readable and writable memory tags

Ubimedia is a concept where media files are embedded in everyday objects and the environment. We propose an approach where the user can read and write these files with his/her personal mobile phone simply by touching the physical objects. This facilitates easy access and storage of, e.g. video and audio files related to the physical object in question. This paper describes our work in developing a technical solution for ubimedia and studying user acceptance of forthcoming ubimedia services. Our technical development of the ubimedia concept has been focused on a mobile phone platform with a tag reader/writer, memory tags with large storage capacity, and the communication between the phone and the tags. Currently, the technical design is in test and evaluation phase. The preliminary results show that the concept works and it can be implemented technically. In parallel with the technical development, we have studied usage possibilities for ubimedia and user acceptance of future ubimedia services. User acceptance has been studied in a web survey and in user evaluations of proofs-of-concept. In addition, an ethical assessment has been carried out. The users appreciated especially the simplicity, speed, low cost and reliability of ubimedia. Ethical concerns were related to control over the download with regard to viruses and other unwanted content.     

Tacticity distribution of isotactic polypropylene prepared with heterogeneous Ziegler-Natta catalyst. 2. Application and analysis of SSA data for polypropylene

Accurate characterisation of the tacticity distribution in isotactic polypropylene is important for obtaining better structure property correlations and for the indirect investigation of the active sites in heterogeneous Ziegler-Natta catalysts. In this work, successive self-nucleation and annealing (SSA) DSC measurement is applied for the study of tacticity distribution in polypropylene fractions with varying isotacticity. The results are compared with ¹³C NMR and temperature rising elution fractionation (TREF). Analysis of the lamellar thicknesses and average meso sequence lengths (MSL) revealed that the fractions could be classified into three main groups according to the lamellar structure generated in SSA. The fractions with relatively low isotacticity crystallise mainly by the longest crystallisable sequence of the chain. In more isotactic fractions, the lamellar thicknesses are close to the average crystallisable sequence lengths of the chains. For the highest isotacticity fractions correlation was not found. Because of these differences the correlation between the melting temperature and isotacticity (meso diad-%) was non-linear. Good correspondence between the SSA melting curves and the TREF fractograms was observed.     

Crystallographic Analysis of Isothermally Transformed Bainite in 0.2C-2.0Mn-1.55Si-0.6Cr Steel Using EBSD

The crystallography of bainite,transformed isothermally at 450℃in 0.2C-2.0Mn-1.5Si-0.6Cr steel,was investigated by electron backscatter diffraction(EBSD) analysis.The orientation relationship(OR) was found to be closer to Ntshiyama-Wassermann(N-W) than Kurdjumov—Sachs orientation relationship.Bainite microstructure consisted of parallel laths forming a morphological packet structure.Typically,there were three different lath orientations in a morphological packet.These orientations were dictated by a three specific N—W OR variants sharing the same {111} austenite plane.A packet of bainite laths with common {111} austenite plane was termed as crystallographic packet.Generally,the crystallographic packet size corresponded to the morphological packet size.Locally,crystallographic packets with only two dominant orientations were observed.This indicates strong local variant selection during isothermal bainite transformation.The relative orientation between the variants in crystallographic packets was found to be near 60°/<110>.This appears to explain the strong peak observed in the grain boundary misorientation distribution near 60°.Bainite also contained pronounced fraction of boundaries with their misorientation in the range of 2.5°—8°with quite widely dispersed rotation angles.Spatially these boundaries were found to locate inside the bainite laths,forming lath-like sub-grains.     

Effect of Boron on the Strength and Toughness of Direct-Quenched Low-Carbon Niobium Bearing Ultra-High-Strength Martensitic Steel

The effect of boron on the microstructures and mechanical properties of laboratory-control-rolled and direct-quenched 6-mm-thick steels containing 0.08 wt pct C and 0.02 wt pct Nb were studied. The boron contents were 24 ppm and a residual amount of 4 ppm. Two different finish rolling temperatures (FRTs) of 1093 K and 1193 K (820 °C and 920 °C) were used in the hot rolling trials to obtain different levels of pancaked austenite prior to DQ. Continuous cooling transformation (CCT) diagrams were constructed to reveal the effect of boron on the transformation behavior of these steels. Microstructural characterization was carried out using various microscopy techniques, such as light optical microscopy (LOM) and scanning electron microscopy-electron backscatter diffraction (SEM-EBSD). The resultant microstructures after hot rolling were mixtures of autotempered martensite and lower bainite (LB), having yield strengths in the range 918 to 1067 MPa with total elongations to fracture higher than 10 pct. The lower FRT of 1093 K (820 °C) produced better combinations of strength and toughness as a consequence of a higher degree of pancaking in the austenite. Removal of boron lowered the 34 J/cm² Charpy-V impact toughness transition temperature from 206 K to 158 K (?67 °C to ?115 °C) when the finishing rolling temperature of 1093 K (820 °C) was used without any loss in the strength values compared to the boron-bearing steel. This was due to the finer and more uniform grain structure in the boron-free steel. Contrary to expectations, the difference was not caused by the formation of borocarbide precipitates, as verified by transmission electron microscopy (TEM) investigations, but through the grain coarsening effect of boron.     

Effective new chemicals to prevent corrosion due to chlorine in power plant superheaters

Firing or co-firing of biomass in efficient power plants can lead to high-temperature corrosion of superheaters due to condensation of alkali chlorides into superheater deposits. Corrosion can be prevented if a significant portion of the alkali chlorides present in the flue gases is destroyed before reaching the superheaters. The alkali capturing power of aluminium and ferric sulphates was determined in a pilot-scale fluidised bed (FB) reactor. The reagents were added in solution, through a spraying nozzle, to the upper part of the freeboard. Both reagents, at economical dosages, fast and effectively destroyed the alkali chlorides by producing sufficient SO₃ for the sulphation. Both the mass flow rate and type of sulphate affected the sulphation ability. Thus, the cation, too, plays a role in the reaction. The required chemical dosage is not directly proportional to the S_reagent/Cl_2fuel ratio because alkali chlorides must compete with calcium and magnesium oxides and probably also with alkali oxides for the available SO₃.     

A decision support system for paper making based on simulation and optimization

In this paper a model-driven decision support system related to paper making is introduced. The intention is to emphasize the necessity of coupling different modeling techniques, multiobjective optimization, and software engineering in order to make the end user application realistic, practical and usable. Firstly the paper making process and selected aspects concerning its mathematical modeling, numerical simulation, and multiobjective optimization are introduced, then the related computerized system, called a virtual paper making line, is described. In addition, the associated decision support system, which provides a suitable level of automation to improve the quality of decision making and support the user’s expertise is discussed. Finally, an example presents different ways of using such a software tool.     

Damage observed in silicon diodes after low energy pion irradiation

We present results of irradiation tests performed in the pion beam of the Paul Scherrer Institute. Our results confirm the prediction, that the Δ-resonance is reflected as an enhancement of the damage caused by low energy pions. At the peak of the Δ-resonance we measure a damage constant 1.5 times higher than generally adopted for neutrons and high energy protons. This result means that the lifetime of silicon detectors close to the vertex at LHC experiments will be limited by the pion background. We predict type inversion of high resistivity detectors to occur after two months of full luminosity and the depletion voltage to reach 200 V within the first four years, even if the detectors are operated at 0°C.