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polymers may improve their mechanical behaviour (stiffness [ 3 – 6 ], failure resistance [ 7 , 8 ] and dimensional stability [ 6 , 9 , 10 ]), their gas and solvents barrier properties [ 11 – 13 ] and their thermal degradation and chemical resistance [ 6
approached with an electrical circuit model consisting of serial connection of a resistance and two distributed elements ( Grimnes and Martinsen, 2008 ): (1) R 0 + R 1 1 + ( i ω τ 1 ) ψ 1 + R 2 1 + ( i ω τ 2 ) ψ 2 , where R 0 , R 1 and R 2 are
variables [ 34 ]. This provides some physical property selection capability for engineering applications. One of the limiting behaviors of several Zirconia containing materials is the thermal shock resistance. This behavior is strongly related to the
method suffers other discrepancies because of the interference of the thermal contact resistance caused by having to use multi-layer stacking samples and the associated residual local natural convection. In this article, the authors developed a
The most current in vitro and in vivo results in the BioArena system and under greenhouse conditions provide a good opportunity for a fundamental renewal of biological detections and interactions in layer liquid chromatography. The adsorbent bed in a column liquid arrangement is not suitable for biological detection because the living cells do not grow there. Contrarily, the planar adsorbent layer enables the in situ biodetection of antimicrobials and the interactions among separated compounds, cells, and further various cofactors (molecules), making the study of mechanisms of action possible. The basic elements of the time- and dose-dependent quadruple immune response of plants to pathogens in relation to the function and reactions of formaldehyde and its reaction products (mainly endogenous ozone) were demonstrated. This finding opens a new horizon in the field of disease resistance in plants and perhaps in general in the biological world. These results give a good basis and possibility for studying and understanding the unique high-dilution phenomena as well, and at that time, they promise the elimination of century contradictions in this field.
Abstract
In this work the thermal properties of chitins of different origin were compared using a thermogravimetric technique. The αs-αr method, which makes possible a comparison of the thermal resistances of materials with similar thermostability, was used. The basic range of thermal conversion was determined. In this range, the thermal resistance depends on the chitin origin. The value of activation energy was calculated. No influence on the average molecular mass, crystallinity and the degree of acetylation on the thermal resistance was observed. On the other hand, it was found that the thermal stability depends on the size and perfection of crystallites as well as on the crystalline form of the chitin.
Abstract
The applicability of MDF synthesis procedure, the coincidence of the interfacial cross-linking and the moisture resistance of MDF-related mixes based on two industrial Portland cements (CEM I, CEM II) and poly-P are reported. The knowledge of the moisture resistance of synthesized material is of paramount importance; two independent experimental methods confirmed that the moisture resistance of MDF cements based on CEM I (or CEM II) with 5% of poly-P achieves sufficient levels at 50% RH and at ambient values of RH. The results of thermal analysis are directly related to the former knowledge on the appearance and role of cross-links in the interfacial zone of MDF cements.
Hepta isobutyl polyhedral oligomeric silsesquioxanes (hib-POSS)
A thermal degradation study
the results over reported. Some considerations are possible on the results obtained: the initial decomposition temperatures of our hib-POSSs in flowing nitrogen were higher than those in static air atmosphere, thus meaning lower resistance to
Abstract
Four types of membrane filter have been studied with respect to trace element contamination and resistance to damage during irradiation with neutrons. Filters consisting of a teflon membrane and a polyolefin ring were low in all trace elements except zinc but failed mechanically during irradiation. Teflon filters backed with polyethylene or polypropylene were low in contamination and possessed excellent resistance to irradiation damage. Polycarbonate filters proved high in bromine and copper and became brittle during irradiation.
defense responses associated with localized and systemic resistance to Phytophthora parasiticainduced in tomato by an arbuscular mycorrhizal fungus . Molecular Plant-Microbe Interactions . 11 . ( 10 ) 1017 – 1028
