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Abstract   We provide a convenient recipe for fabricating reliable superconducting microbolometers as acoustic phonon detectors with sub-nanosecond response, using image-reversal optical lithography and dc-magnetron sputtering, and our recipe requires no chemical or plasma etching. Our approach solves the traditional problem for granular aluminium bolometers of unreliable (i.e., non-Ohmic) electrical contacts by sequentially sputtering the granular aluminium film and then a palladium capping layer. We use dc calibration data, the method of Danilchenko et al. (Acta Phys. Pol. A 103(4):325, [2003]) and direct nanosecond-pulsed photoexcitation to obtain the microbolometer’s characteristic current, thermal conductance, characteristic relaxation time, and heat capacity. We also demonstrate the use of the deconvolution algorithm of Edwards et al. (J. Phys. E Sci. Instrum. 22:582, [1989]) to obtain the phonon flux in a heat pulse experiment with nanosecond resolution. [ABSTRACT FROM AUTHOR]

Abstract: A solid electrolyte type nitrogen oxides (NO x ) gas sensor was fabricated by applying an Al3+ cation conducting solid electrolyte with the KNO3-doped (Gd0.4Nd0.6)2O3 solid solution and Al metal as the auxiliary sensing electrode and the reference electrode, respectively. A rapid, reproducible and continuous sensor response was obtained with obeying the theoretical Nernst relationship for NO and NO2 gases at the temperature as low as 250°C, one of typical temperature of emitted gases. [Copyright &y& Elsevier]

Abstract: The present study demonstrates different approaches towards MIC identification in three real cases of technological equipment failures. In the first case the failure of carbon steel heat exchanger as a result of tubes, lids, tube sheets, and connection pipes clogging was investigated. Chemical analysis of cooling water and precipitates, as well laboratory screening of deposits for bacteria, revealed that activity of iron-oxidizing bacteria present in cooling water led to heat exchanger blockage. The second case is related to MIC detection on floating roofs made of magnesium–aluminum alloy following a 3-weeks hydro-test. Corrosion tests carried out on the original and sterilized water used in hydro-test confirmed MIC process. In the third case the potential of MIC occurrence in engine cooling system made of cast aluminum alloy and filled with 20% ethylene glycol coolant solution was evaluated. The simulation tests allowed determining the real causes of the severe corrosion attack of examined system, including MIC high probability. [Copyright &y& Elsevier]

Abstract: Dry machining and high speed machining are increasingly attempted because of their impact on manufacturing cost. However, these processes generate dust that can be harmful. Environmental regulations require that manufacturers reduce manufacturing hazards, hence the need to develop environmentally conscious processes and cutting strategies that will help them to achieve that goal. This work investigates the turning of the 6061-T6 aluminium alloy, and 1018 and 4140 steels, using carbide cutting tools. The cutting tool geometry and the cutting speed are varied and their effect on dust formation and chip formation studied. The size of the dust particle investigated is 2.5μm and under (PM2.5). A new dust unit, which can be used as an ecological factor, is introduced to compare the dust emissivity of the tested materials. This dust unit is then related to the cutting conditions, and experimental models are developed. A correlation is established between the chip formation, the tool lead angle, the cutting speed, and the dust emission, in order to determine the conditions required for minimal dust emission. [Copyright &y& Elsevier]

Abstract: A kinetic study of dissolution reaction of Al can waste was conducted for the synthesis of aluminum isopropoxide (AIP). With the used Al can and isopropyl alcohol (IPA) as reactants, the reaction was examined at the condition of 3molIPA/mol Al of stoichiometric ratio, adding 10−3 molHgI2/mol Al for catalyst and no agitation at the reaction temperature ranging from 70 to 82°C. After 17h, the reaction gave a 75% yield. A two-stage dissolution mechanism was proposed in which the dissolution rate is determined first by a chemical reaction and then by ash layer diffusion. On the basis of the shrinking core model with the shape of flat plate, the first dissolution rate of Al can was controlled by chemical reaction. The concentration of isopropyl alcohol was added to the reaction at the stoichiometric ratio, then it was largely changed through the dissolution reaction. Therefore, since the conversion rate of isopropyl alcohol varies greatly depending on the reaction time, it was included as an integral term of the reaction time. By using the Arrhenius expression, the apparent activation energy of the first chemical reaction step was determined to be 92.4kJmol−1. In the second stage, the dissolution rate is controlled by diffusion control through the ash layer. The apparent activation energy of the second step was determined to be 174.9kJmol−1. [Copyright &y& Elsevier]

Abstract: A new method for micropatterning of metallic patterns on porous anodic oxide film of aluminium is described. The porous anodic oxide film was impregnated with organic dye and palladium ions before the hydrothermal pore-sealing. The surface layers formed during the pore-sealing, i.e. outer acicular hydroxide layer and a compact intermediate sub-layer trap the palladium ion underneath the layers. Exposing the palladium enriched area by the help of laser beam followed by electroless nickel deposition results the deposition of nickel on the laser-exposed part. Thickness of the deposits can be up to about 2–3μm, after about the 20min of immersion in electroless nickel plating bath. The metallic micropatterns, formed by the method are crack free, smooth and uniform over extended length. [Copyright &y& Elsevier]

Abstract: We studied the aluminum-induced early alteration of cultured diatom frustules in a series of laboratory experiments. Ashed frustules of the diatom Thalassiosira punctigera were exposed to natural seawater at varying dissolved aluminum (Al) concentrations (without addition, 100 nM and 500 nM Al) for periods of up to 6 months both in batch incubations and in flow-through chambers. These Al concentrations are representative of levels commonly found in pore waters in the marine environment. In general, the aluminum content of the frustules increased with time of exposure. A maximum increase of the aluminum to silicon mole ratio from 1.23×10−3 (day 0) to 3.14×10−3 was observed after 14 days of incubation at 500 nM Al. Time series with incubation times from 1 to 21 days at 100 nM Al confirm that the aluminum is rapidly associated with the diatom frustule. The uptake of Al during incubation goes along with a shift in pore structure towards smaller pores. The structural association of aluminum and silicon in biogenic silica was investigated using X-ray absorption spectroscopy at the Al–K-edge. Al–K-edge X-ray adsorbtion near edge spectra (XANES) of incubated diatom frustules demonstrate that most aluminum is present in tetrahedral coordination regardless of the Al concentration of the seawater and the duration of exposure. Al–K-edge EXAFS spectroscopy indicates the structural incorporation of aluminum into the Si framework. The results from X-ray absorption spectroscopy at the Al–K-edge, the textural changes of diatom frustules during incubation and wet chemical data are all consistent with the formation of an aluminosilicate phase on the surface of the diatom frustules. The precipitation this surface phase occurred under experimental conditions mimicking those prevailing at the sediment–water interface. We propose that the documented reaction pathway contributes to the rapid post-mortem aluminum enrichment of diatom frustules at the sediment–water interface. [Copyright &y& Elsevier]