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Abstract

These days, the investigations of the physical properties of the insulating materials are very important. In this paper we report the measured water uptaking capabilities of a thermal insulating paint. They can be found in liquid phase, but we measured dried solid samples. The thin thermal insulators (insulator coatings) are starting to spread on the market of the building materials. The proper understanding of sorption behavior of the materials is important from the applied building technology point of view. Moisture sorption and desorption measurements were carried out on two samples with different geometry by using climatic chamber method. After drying the samples at 90 °C for one hour in the Venticell 111 type drying equipment they were wetted with a Climacell 111 type climate chamber, where the relative humidity (RH) was varied from 25% to 90% at 293 K for 2 hours. The samples were wetted for 2 and 4 hours as well. Sorption and desorption as well as kinetic curves are presented in this paper.

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Journal of Thermal Analysis and Calorimetry
Authors: Ticiano do Nascimento, Irinaldo Basílio Júnior, Rui Macêdo, Elisana Moura, Camila Dornelas, Vanderson Bernardo, Vânia Rocha, and Csaba Nóvak

Abstract  

This article characterizes the stability of indinavir sulfate using different analytical techniques of quality control to evaluate important steps in the manufacturing process of indinavir, specifically involving storage and compression. Indinavir A, B, and C were obtained from different suppliers and submitted to DSC, Karl Fisher, NIR, XRPD analyses and dissolution assay. DSC curves of indinavir presented endothermic peaks of fusion at 149–150 °C for indinavir A and B (form I) and 139–143 °C for indinavir C (form II). When indinavir A and B were submitted to high Relative Humidity (RH) pseudo-polymorphic form II was formed. Indinavir C converted into an amorphous substance when submitted to compression. Near infrared and Karl Fisher assays detected high values of water for indinavir C in relation to indinavir A and B. X-ray powder diffraction of indinavir B and C showed displacement of 0.05–0.10 θ in the peaks and higher angle of diffraction in relation to indinavir A. Amorphous indinavir C demonstrated a higher intrinsic dissolution rate than indinavir A and B. Indinavir form I should be monitored during the pharmaceutical process to avoid its conversion to indinavir form II or an amorphous substance which can alter the dissolution rate.

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Abstract  

7Be activity concentrations were measured in the lower atmosphere at Thessaloniki, Northern Greece (40°38′N, 22°58′E) over the year 2009, a year of a particular minimum of solar activity. The mean annual activity concentration of 7Be at that year was 6.01 mBq m−3. The variability of 7Be surface concentrations related to the solar cycle appeared to be deviated about 40% between the maximum and the minimum values. A positive correlation (R = 0.97) was revealed between the activity concentrations of 7Be and the temperature, confirming that the increased rates of vertical transport within the troposphere, especially during the warmer months, resulted in carrying down to the surface layer air masses enriched in 7Be. Relatively high values of 7Be activity concentrations were observed by increasing of the tropopause height. A negative correlation (R = −0.65) between the 7Be activity concentrations and the relative humidity was due to the condensation process in the lower atmosphere which resulted in increased aerosol particle sizes with higher scavenging rates of aerosols and low activity concentrations of 7Be in the atmosphere. Influence of precipitation on the changes of 7Be activity concentrations was also observed.

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Abstract  

The seasonal variation of the 7Be activities in air and the size distribution of the 7Be aerosols were studied by using a continuous air sampler and a five stage cascade impactor. The mean monthly activity level of 7Be at the Korea Atomic Energy Research Institute (KAERI) site varied from 0.5 to 4.8 Bq·m−3 and revealed a seasonal variation, in which the 7Be activity levels were high in winter and low in summer. The mass size distribution showed a bi-modal distribution with a higher peak around 0.49 μm and a smaller peak between 3 μm and 7.2 μm. The activity median aerodynamic diameter (AMAD) decreased with increasing ambient 7Be concentrations. The mean residence times by using a mean growth rate of 0.004 μm·h−1 were estimated to be 2.5–6.4 days. The AMAD has an increasing tendency with higher relative humidity. It seemed that the high humidity condition facilitated the growth of the aerosol, resulting in increased deposition rates of the aerosols and the low 7Be content in the surface air. The AMAD of the 7Be aerosols increased with an increasing temperature, but the temperature dependency of AMAD should be explained with geological and meteorological conditions.

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Acta Chromatographica
Authors: M. Pacenti, S. Dugheri, R. Gagliano-Candela, G. Strisciullo, E. Franchi, F. Degli Esposti, N. Perchiazzi, P. Boccalon, G. Arcangeli, and V. Cupelli

Summary

2-Chloroacetophenone (CA) is widely used as tear gas by law-enforcement agents, and by civilians for personal protection. Crimes involving robbery and rape using tear gas sprays have recently increased. Experimental and in-field evaluations have been performed to validate use of solid-phase microextraction (SPME) with a porous fiber for sampling and analysis of CA in air before analysis by fast gas chromatography-mass spectrometry equipped with a new device called a multi-fiber system. CA vapor was generated by use of a syringe pump in a dynamic system in which temperature, relative humidity, and air velocity were monitored. The theoretical sampling rate for time-weighted average and rapid-SPME were, furthermore, estimated by use of the Fuller-Schettler-Giddings diffusion coefficient and the theory of heat transfer, respectively, and were in accordance with experimental values. Concentrations of CA were analyzed in a military store containing tear gas canisters, to evaluate the risk. The results obtained in this field study showed values ranging from 0.206 to 2.46 mg m−3.

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The development of high performance insulating materials incorporating nanotechnologies has enabled considerable decrease in the effective thermal conductivity. Besides the use of conventional insulating materials, such as mineral fibers, the adoption of new nano-technological materials such as aerogel, vacuum insulation panels, graphite expanded polystyrene, is growing. In order to reduce the thermal conductivity of polystyrene insulation materials, during the manufacturing, nano/micro-sized graphite particles are added to the melt of the polystyrene grains. The mixing of graphite flakes into the polystyrene mould further reduces the lambda value, since graphite parts significantly reflect the radiant part of the thermal energy. In this study, laboratory tests carried out on graphite insulation materials are presented. Firstly, thermal conductivity results are described, and then sorption kinetic curves at high moisture content levels are shown. The moisture up-taking behaviour of the materials was investigated with a climatic chamber where the relative humidity was 90% at 293 K temperature. Finally, calorific values of the samples are presented after combusting in a bomb calorimeter.

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Abstract

The relationship between water body (fountains) scale and climate parameters like wind speed, air temperature, relative humidity, as well as thermal comfort index was modeled and analyzed via Envi-met code. Taking the water impact and factors analysis as a research object, the factors mainly discussed in this research are square area to water-body area ratio and the location of the water element. However, the computational fluid dynamics simulations were conducted on the following scenarios: 3% (original base case), 6%, and 9% of the total square's area, then the outputs of the two simulation results were compared to the original base case. The results revealed that water scale has a slight effect on the micro-climate of the built environment in the summertime in moderately warm-wet climate zone. However, it is beneficial to adjust temperature and humidity in public spaces of central European cities. Nonetheless, the main aim of this paper is to quantitatively investigate the impact of the water bodies on the urban weather parameters and human thermal comfort under the influence of different scale ratios in Pecs-Hungary.

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Sensory and physicochemical changes of three apple cultivars (‘Golden Delicious’, ‘Idared’ and ‘Gloster’) were monitored during 14 weeks of storage at 6 °C and 70% relative humidity in three following years. The aim was to investigate physicochemical parameters that were best correlated with sensory evaluation of apples during their storage. Sensory quality was assessed using a category point scale and the sensory profile was evaluated using a graphical unstructured scale. Physicochemical changes, such as weight, soluble solids, titratable acidity, and dry matter content, were monitored. All the examined parameters changed during the observed period, with the greatest changes occurring in weight, texture, and taste. There were also differences between the tested cultivars. Statistically significant correlations between sensory and physicochemical data were observed between texture characteristics and weight changes. In case of sweet taste, only a weak correlation between the intensity of sweet flavour and soluble solid content values was found. No statistically significant correlation between the intensity of sour taste and titratable acidity was observed.

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Acta Veterinaria Hungarica
Authors: Lydia Gil, S. Saura, Arantxa Echegaray, Felisa Martinez, I. de Blas, A. Akourki, Noelia Gonzalez, E. Espinosa, and A. Josa

The present study evaluated the effect of supplementing the medium used to mature equine oocytes in vitro with oestrous mare serum (EMS) or horse follicular fluid (HFF). To this end, 144 ovaries were obtained from mares aged 16-21 months and transported to the laboratory in Dulbecco's phosphate buffered saline (D-PBS) at 30°C. Oocytes were harvested from the ovaries by slicing, and then selected for in vitro maturation (IVM) according to the number of cumulus cell layers and the characteristics of the cytoplasm. The selected oocytes were washed three times in TCM199 medium plus HEPES (TCM-199H) or in the same medium plus glutamine (TCM-199G), then matured in vitro in six study groups established according to the in vitro maturation (IVM) treatment to see possible interactions between HEPES and glutamine on other supplements: Ten percent EMS was added to two of these media (TCM-199H+EMS and TCM-199G+EMS) and 10% HFF was added to the media in two other groups (TCM-199H+HFF and TCM-199G+HFF). IVM was performed at 38.5°C for 40 h in a controlled atmosphere (5% CO2, 95% relative humidity). The findings indicate that the presence of EMS or HFF in the TCM-199H medium gives rise to the best results in terms of the proportions of oocytes reaching maturity (37.7% and 36.8%, respectively). The values obtained with EMS and HFF were statistically similar to each other but differed from the other treatments. The media containing glutamine led to the highest proportions of degenerated oocytes.

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How are bryophyte alpha and beta diversities distributed across spatial scales along an elevational gradient in an oceanic island? Which mechanisms and drivers operate to shape them? Starting from a multiscale hierarchical sampling approach along an 1000 m elevational transect, we used additive diversity partitioning and null modeling to evaluate the contributions of the alpha and beta diversity components to overall bryophyte diversity in Terceira Island, Azores. Substrate-level diversity patterns were explored by means of the Sørensen Similarity Index and the Lloyd Index of Patchiness. Elevation-level beta diversity was decomposed into its replacement and richness differences components, with several environmental variables being evaluated as diversity predictors. Bryophyte diversity proved to be primarily due to beta diversity between elevation sites, followed by diversity among substrates. Compositional differences between neighboring sites decreased with elevation, being mainly caused by species replacement and correlating with differences in relative humidity and disturbance. At the substrate level, we found a great homogeneity in terms of species composition, coupled with a low substrate specialization rate. We conclude that, in Terceira’s native vegetation patches, regional processes, such as environmental gradients associated with elevation, play a greater role in shaping bryophyte diversity than local processes. Moister and less disturbed areas at mid-high elevation harbor a richer bryoflora, consistently more similar and stable between neighbouring sites. Simultaneously, the different substrates available are somewhat ecologically redundant, supporting few specialized species, pointing to these areas providing optimal habitat conditions for bryophytes. Our findings provide a better understanding of how bryophyte diversity is generated in Terceira Island, indicating that management and conservation measures should focus on island-level approaches, aiming to protect and rehabilitate additional natural vegetation patches at different elevations, especially in the severely disturbed lowlands.

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