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Summary Anhydrous lactitols (A1, α- and β-lactitol), lactitol monohydrate, lactitol dihydrate and lactitol trihydrate were kept for varying times in atmospheres of different relative humidity at 20°C in equivalent size plastic desiccators. The relative humidities (8-95%) were maintained with saturated salt solutions and drying agents (silica gel and phosphorous pentoxide). The composition of the samples was monitored by thermogravimetry, differential scanning calorimetry and X-ray powder diffraction. According to these measurements both lactitol monohydrate and lactitol dihydrate were substantially stable under the conditions used. Lactitol monohydrate converts to lactitol dihydrate at the highest relative humidity used. All phases of anhydrous lactitol convert into a form of lactitol monohydrate but not to lactitol dihydrate, even at the highest relative humidity used. At a high relative humidity lactitol trihydrate easily loses part of its crystal water and converts partly to lactitol dihydrate. At a lower relative humidity, the phase forming from trihydrate is difficult to identify.

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Edible wheat gluten (WG) protein films

Preparation, thermal, mechanical and spectral properties

Journal of Thermal Analysis and Calorimetry
Authors: S. C. Mojumdar, C. Moresoli, L. C. Simon, and R. L. Legge

used since it is closely related to dispersion coating, an interesting potential application technique for vital WG on e.g., paperboard in packaging applications. The films were stored at 50% relative humidity (RH) on a blotting paper. The aim was to

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Journal of Thermal Analysis and Calorimetry
Authors: A. Kyritsis, A. Spanoudaki, C. Pandis, L. Hartmann, R. Pelster, N. Shinyashiki, J. C. Rodríguez Hernández, J. L. Gómez Ribelles, M. Monleón Pradas, and P. Pissis

on polymer dynamics in the nanocomposites. To that aim, dielectric measurements are performed at several levels of water activity (relative humidity)/water contents at each xerogel composition, to systematically follow the evolution of dynamics and of

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J. , Field J.P. , Felix O. , Corral-Avitia A.Y. , Saez A.E. , Betterton E.A. , 2014 . Effect of wind speed and relative humidity on atmospheric dust concentrations in semi-arid climates . Sci. Total Environ. 487 . 82 - 90

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Abstract  

DNA adsorbed very low amount of water at low relative humidities, amount of adsorption increased to 140% at 98% relative humidity at 25°C. Heat of adsorption was 109 kJ mol-1 H2O for the increase of moisture content from 0 to 1.96%. At higher moisture contents the heat released approached heat of condensation of water vapour on free liquid surface, 40 kJ mol-1 H2O.

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. The conditions used are (a) 25 °C/30% relative humidity (RH), and (b) 85 °C/85% RH. Results and discussion Fast-scan TG analysis/differential thermogravimetry It has been previously mentioned that

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Abstract  

Effects of humidity and light conditions /fluoroscent light, sunlight and diffuse sunlight/ on the response of 2 mm thick clear polymethylmethacrylate /PMMA/ dosimeter during irradiation and during postirradiation storage were determined spectrophotometrically at 305 and 314 nm. The results showed that irradiation of dosimeters at 12–97% relative humidity did not result in any change in the response upto 2 weeks of post-irradiation storage. However, there is some decrease in the response at higher humidities />76%/ for longer storage time. Post-irradiation storage and dosimeters at constant relative humidity conditions between 35 and 97% had no effect on the response up-to 3 weeks. Post-irradiation storage at lower relative humidity /12%/ showed some decrease in the response for longer periods. The response of dosimeter is not very sensitive to short time exposure to diffuse sunlight and fluorescent light. However, a significant increase in the optical density was observed during exposure of dosimeters to direct sunlight.

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Journal of Thermal Analysis and Calorimetry
Authors: Juliana Cordeiro Cardoso, Ricardo Luiz C. Albuquerque Jr., Francine Ferreira Padilha, Felipe Oliveira Bittencourt, Osvaldo de Freitas, Paula Santos Nunes, Newton L. Pereira, Maria José Vieira Fonseca, and Adriano Antunes S. Araújo

. Table 1 Permeability of casein and modified casein films with 20% of glycerin at different relative humidity and the percentage of erosion of films in aqueous and acid environment after 8 h

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Abstract  

The effects of incorporating tritiated water into a 14C-sampling system in sample preparation and 14C activity measurement by liquid scintillation counting were investigated. Experiments derived the limit of water content in the prepared sample, and also demonstrated that 14C activity can be determined without any interference from 3H contamination for a clear-sample solution. The results enabled us to estimate the permissible relative humidity of air required for accomplishing sample preparation and 14C activity measurement. These showed that for sampling of air with less than the permissible relative humidity, total 14C activity in airborne effluent can be evaluated accurately without dehumidification of air.

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conditions—contact time, kind of light, intensity of illumination, relative humidity of the feed and the oxygen/pollutant feed ratio. These investigations are usually carried out using a standard reference photocatalyst, most often it is TiO 2 Degussa P25

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