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Abstract  

Several lactose samples containing various amounts of amorphicity were studied with an isothermal microcalorimetric technique, which allow to detect the heat and the quantity of water sorption simultaneously. As interaction with vapor is characteristic of different surfaces, the samples were easy to be discriminated from each other by studying sorption behavior. With the crystalline lactose samples, the amount of sorbed water was too minor to be detected reliably with the technique, but differences were found when the energy values (J g−1) were compared. In the future work, the measurement set-up will be improved so that sorption rates less than 0.1 nmol s−1 can be measured repeatably and reliably.

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Abstract  

A well-known photolabile substance, nifedipine, was used as a sample material to test self-constructed irradiation cells and demonstrate their usefulness in photostability studies. The devices were made as accessories for a commercial isothermal microcalorimeter. Several powder samples containing various amounts of moisture were irradiated with monochromatic light as a scan measurement from 700 to 280 nm, and the heat flow evolved in the photodegradation of nifedipine was determined. According to the results, light does not affect the nifedipine molecule directly, but the photodegradation is a result of the combined effects of moisture and light.

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Abstract  

The specific heat capacities (cp) for the brain and muscle equivalent liquids were determined with isothermal heat conduction microcalorimetry (IMC) and differential scanning calorimetry (DSC). IMC was found to afford an accurate technique to measure cp for solid and liquid samples, when an appropriate reference is employed. The accuracy of obtained cp values was estimated to be better than 0.7% with the equivalent liquids. Intercomparison with a conventional isoperibolic calorimeter showed an excellent agreement within the estimated uncertainty of the isoperibolic calorimeter (3%). Additionally, suitability of different kinds of IMC sample vessels was tested, and the standard electrical calibration procedure of IMC was evaluated through the determination of cp with and without a reference material.

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Scientometrics
Authors: R. K. Buter, E. C. M. Noyons, M. Van Mackelenbergh, and T. Laine

Summary  

Bibliometric maps of science are a well-established research subject. But their adoption as a science policy support tool is lacking. We think this is because the user does not immediately comprehend a map and (as a result) is not enticed into using it. To help this comprehension, we propose the use of “qualitative maps”: an umbrella term for diverse tools such as concept maps and mental maps. We developed a tool that interfaces between a qualitative map and a bibliometric map which lets the user create a correspondence between the distinct vocabularies of the maps. We also conducted two user studies: the first explored the combined use of bibliometric and qualitative maps and the second the preferred format of the map and the word-usage in the description of its elements.

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