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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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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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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  

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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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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In order to examine the complex role of the vegetation structure determining microclimate, the authors carried out temperature and relative humidity measurements in beany fens, drying fens, semidry grasslands, hayfields, steppe grasslands, rocky grasslands and open sandy grasslands of the Transdanubian mountains. In the course of this process, measurement and data recording took place annually with four repetitions (June, July, August, September) per sampling area in identical weather conditions, resulting in altogether 162 sampling occasions in 84 sampling areas on the ground surface and at a height of 10, 20, 30 and 120 cm in the grassland. In the present paper measurement data concerning the humidity of grasslands researched to a lesser extent in previous works are assessed. The comparative study ascertains that based on the relative humidity curves depicting microclimate, the samples of the examined types of grassland should be handled as separate groups in each sampling period. A further result to be seen is that in the case of several grasslands (semidry grasslands, drying fens) aspect change can also be detected in the change of microclimate (decrease of the relative humidity). The shift in relative humidity curves towards drying can be most conspicuously seen in the case of semidry grasslands.

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Abstract  

The use of non-aqueous deacidification procedures as a preventive conservation measure to assist in retarding the deterioration of painting canvases has been suggested by the Conservation Department of the Tate Gallery [1]. The reverse sides of paintings are treated with commercially available MMC solution (methoxy magnesium methyl carbonate). The aim of this paper is to describe how dynamic mechanical thermal analysis can be used to evaluate the effects of this treatment. Measurements are described on modern commercially primed canvas samples [2] which show that the MMC treatment does cause an increase in the modulus or stiffness of the primed canvas materials but that the effect on theT g is minimal. The response of the treated materials to variations in relative humidity has also been studied and indications are that the response of treated canvases to variations in relative humidity differs from those of the untreated canvases.

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Abstract

Numerical research in the context of urban in a humid continental climate zone is still limited. The aim of modeling the case study is to assess the performance of outdoor thermal comfort parameters and investigate their capabilities in achieving the outdoor thermal comfort. A computer-based tool is used to quantitatively study the outdoor thermal comfort and its weather parameters. The parameters have been analyzed using ENVI-met tool and then compared against different comfort scales like relative humidity comfort scale, the predicted mean vote scale as well as other scales and standards. The results have shown that the average predicted mean vote value is +4 (very hot), the average air temperature is hot, the average wind speed is light breeze and the relative humidity falls within the comfort range. However, street orientation, shading, water bodies and plantation play a significant role in increasing and decreasing the outdoor thermal comfort.

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Abstract  

Effects of relative humidity conditions in the irradiation chamber and of temperature of the chamber on the response of 3 mm thick light blue poly (methyl methacrylate) sheets have been studied. The response was measured spectrophotometrically at 402, 450, 596 and 612 nm. The response of the dosimeter is independent of the relative humidity (12–97%) during irradiation if the response is measured within 24 h of irradiation. If the response is measured after longer storage time, the absorbance at 402 and 450 nm increases significantly. At these two wavelengths the response of the dosimeter is also independent of the temperature of the irradiation chamber in the range of 0 to 40 °C. However, at higher temperatures (60, 80 °C), the response is not uniform.

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