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An impact of temperature, light and relative humidity were studied on root colonisation by mycorrhizal fungi and on pine seedling growth. Moderate and high light intensities favoured mycorrhizal colonisation and seedling growth. Pine seedlings inoculated with Pisolithus tinctorius compared to other fungi attained maximum growth. Survival of pine seedlings was higher under moderate light intensity than low and high light intensity. Seedling growth and mycorrhizal colonisation was better at 25°C than 10°C. Variation in humidity did not show much difference in mycorrhizal colonisation and seedling growth. However, seedling survival was greater at high than at low humidity. Pine seedlings showed best survival with 0.5 P level (46.153 mg P/kg soil) of phosphorus at 25 °C temperature and under moderate light intensity. Among the mycorrhizal fungi used P. tinctorius was the most effective endophyte and was followed by Laccaria laccata, Rhizopogon luteolus and Collybia radicata under various physical factors.

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Main aim of this paper is to illustrate the experimental partial results of a study on various exterior wall fragments. The study was performed for selected wall fragments and time periods, with attention focused also on wall orientation (East and South) with identical layering and also on dynamic thermal parameters connected to the thermal comfort during summer and winter. Evaluation is done for real measured climate conditions in the area of experimental laboratory (exterior – University of Zilina) and interior conditions set according to the Slovak standard. For needs of the long-term experiment (since March 2017), temperature and relative humidity between layers are monitored. This paper deals specifically with the temperature measurement of selected days. For future publications also coupled heat-air-moisture transport analysis is intended. In this part of analysis, some extreme boundary conditions were selected and reviewed from the point of view of measured temperature inside the wall. Temperature peaks are characterized with respect to exposure to real atmospheric conditions.

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This paper is focused on hygrothermal assessment of the eave overhang detail in above-rafter placed thermal insulation roof system. Results of the long-term measurement of this detail performed on a real building as well as the testing of the measuring method are presented in this paper. Within this measurement the moisture of wooden elements performing an eave overhang of the roof was monitored primarily in order to verify their long-term functionality. In addition the temperature and relative humidity in the roof structure were measured as well. As part of this measurement, various design variants of above mentioned detail in combination with different compositions of the roof structure were compared. The long-term functionality of the assessed details is evaluated in the conclusion of this paper, taking into account especially hygrothermal status of wooden element, which is associated with threats of infestation of these elements by wood decaying fungi or insects.

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Journal of Thermal Analysis and Calorimetry
Authors: M. Odlyha, Q. Wang, G. M. Foster, J. de Groot, M. Horton, and L. Bozec

Summary  

Dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC) and thermogravimetry (TG) have been used to characterise model tapestries, especially woven for the EC-funded project (MODHT) and to historic tapestries in royal palaces and museums. Modulus values of woollen threads from model tapestries are reported and the effects of traditional dyeing and mordanting processes quantified. TG, particularly of black woollen threads showed alterations in thermal stability. Tests of creep on immersion in water and subsequent heating to 90C and on exposure to a controlled relative humidity programme were also used to rank these effects. Modulus values of historic woollen samples were also obtained and DSC studies of model and historic silk samples are reported together with preliminary atomic force microscopy (AFM) images of silk fibres.

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It is believed that lipids are the most important factor affecting nuts shelf-life. In the present study, an accelerated shelf-life testing by means of elevated temperatures 62, 72, and 82 °C was conducted to predict the oxidation stability of walnuts over a long-term storage. Peroxide value (PV) was employed to monitor the lipid oxidation progression in the walnuts. A range of 74.01–79.57 kJ mol−1 K−1 energy was required for formation of primary oxidation products. The reaction changes followed an apparent first-order kinetic. Formation of hydroperoxides in walnut kernels was found to be a temperature-dependent reaction with Q10 of 2.1. Walnut kernels were also kept in normal condition (temp: 20–30 °C; relative humidity (RH): 35–45%) for 12 months to validate the shelf-life estimation approach. The results showed that PV could provide a proper estimation for oxidative stability of the walnuts stored in ordinary condition.

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Abstract  

The isothermal heat of hydration of MgSO4 hydrates was studied by humidity controlled calorimetry. Two hydrates, starkeyite (MgSO4·4H2O) and a mixture of MgSO4 hydrates with summary 1.3 mol H2O were investigated. The solid-gas reactions were initiated at 30°C and 85% relative humidity. The heat of hydration was determined in a circulation cell in the calorimeter C80 (Setaram). The crystal phases formed after the hydration process were analyzed by thermogravimetry (TG) and X-ray powder diffraction (XRD). Starkeyite reacted with the water vapour to the thermodynamic stable epsomite and the MgSO4 hydrate mixture with 1.3 mol water to hexahydrite. The hydration heats of starkeyite and the mixture were determined to be −169±3 and −257±5 kJmol−1, respectively.

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Thermal properties of polysaccharides at low moisture

II. Molecular order and control of dissolution temperature in agar

Journal of Thermal Analysis and Calorimetry
Authors: D. Cooke, M. J. Gidley, and N. D. Hedges

Differential scanning calorimetry (DSC) has been used to probe ordered structures and glassing behaviour for a range of agars containing < 25% w/w water. Most commercial agars are supplied in an ordered (double-helical) state, show an endothermic helix-to-coil transition above 100‡C at low-moisture, and require 90–100‡C for solubilisation in excess water. Agars dried from the coil (single-chain) state show no corresponding endothermic transitions and only require a minimum of 45‡C for aqueous dissolution. Evidence from helix-to-coil transition enthalpies, equilibrium water content as a function of relative humidity, and solid-state13C NMR spectroscopy suggests that water molecules are associated enthalpically with double-helical agar. Single-chain agar is apparently not obtained in a glassy state by direct drying from solution, but in common with double-helical forms, exhibits rubber/glass transition behaviour following heating (in a DSC pan) to 180‡C.

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Abstract  

Differential scanning calorimetry and high angle X-ray diffraction analyses were performed on gelatin films, air dried at different values of constant elongation, crosslinked with glutaraldehyde and examined at constant relative humidity of 75%. Drawing induces a preferential orientation of the chain segments of gelatin parallel to the stretching direction,and a linear increase of the renaturation level, calculated as the ratio between the denaturationenthalpy of gelatin films and that of tendon collagen. The comparison with the results previously obtained on the mechanical properties of the films, puts into evidence the different contributions of orientation and renaturation on the improvement of the mechanical parameters on drawing. The results offer important information on the role of glutaraldehyde (GTA) crosslinking on the stability of collagenous materials.

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Abstract  

The stability of Supersulphated Cement (SSC) is investigated at 95°C when subjected to relative humidities of 100, 53 and 11% of water vapour. Previously [1] investigations at 25, 50, 75°C under the same conditions of humidity reported the stability of ettringite, one of the initial hydration products. At 95°C, decomposition of ettringite, is found at all humidities and is rapid at 100% relative humidity. The hydration products of cement pastes at a water cement ratio of 0.27 were determined by thermogravimetry (TG) and X-ray diffraction (XRD). The formation of the hydragarnet, plazolite is recorded during the decomposition/dehydration process enhanced by possible carbonation. Rehydration studies on the products after storage for up to 9 months were carried out using distilled water and the samples tested for ettringite content. It is concluded that ettringite in SSC is inherently unstable at 95°C.

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Changes in the water content of aluminium sulphate hydrate were investigated gravimetrically at room temperature in air with different relative humidities. The samples conditioned in this way were characterized by thermoanalytical (TG, DTG, DSC) and X-ray diffraction measurements. Industrial aluminium sulphate hydrate obtained by freezing the melt has a partly crystalline structure. After grinding, this material crystallizes during storage. This process requires a humid atmosphere; increasing relative humidity brings about more intensive crystallization.

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