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71.
The aim of this work was to study the foaming, gelling and rheological properties of albumen as simultaneously affected by the housing system (i.e. conventional cage, organic and barn) and the age of layers (27, 30, 35, 43, 53 and 68 weeks). Significant effects of the two considered factors and of their interactions were found for almost all the studied properties. In particular, with the increasing of the hen age, a loss in albumen consistency and a weakening of the albumen gel structure were observed. As regards the housing system, differences observed, even if statistically significant, were little and unlikely to have a real effect on technological performances of the eggs when used as food ingredients. Significant correlations amongst technological properties of albumen and its pH and protein content were also found.  相似文献   
72.
The resistance to sulfate attack of mixtures accelerated with alkali-free and alkaline accelerators was found to be mainly influenced by the Al3+ and SO42− added via the admixtures. Microstructural observations showed decalcification and disintegration of the CSH gel, which acted as an additional Ca2+ supplier as compared to the CH for ettringite formation. The CSH decalcification was mainly observed with a homogeneous distribution of the alkali-free admixture. The disintegration of the CSH gel increased the porosity and allowed more sulfate solution to penetrate into the specimens. This process promoted the swelling of the specimens and directly contributed to the expansion, explaining the lack of a direct relationship between the ettringite formation and the expansion. Moreover, the CSH gel disintegration, typical for MgSO4 attack, also occurred with Na2SO4 solutions and depending on the aluminate-sulfate distribution and the extent of the CSH gel disintegration, different damage types were detected. At higher temperatures (65 °C) the damage was mainly controlled by the growth, the rearrangement and the thermal stability of ettringite.  相似文献   
73.
Bone marrow cryptococcosis as initial sign of AIDS. The Authors describe a case of bone marrow cryptococcosis in a patient, female aged 27, in which a toluene-induced aplastic anemia was suspected. The mycosis was at first extracerebral and represented the initial manifestation of unexpected AIDS. The Authors discute the symptomatology and the clinical findings leading to the diagnosis and remark the main point of bone marrow evaluation as aid in diagnosing the infective pathology.  相似文献   
74.
Despite their success as primary treatment for vascular diseases, Nitinol peripheral stents are still affected by complications related to fatigue failure. Hip and knee movements during daily activities produce large and cyclic deformations of the superficial femoral artery, that concomitant to the effects of pulsatile blood pressure, may cause fatigue failure in the stent. Fatigue failure typically occurs in cases of very extended lesions, which often require the use of two or more overlapping stents. In this study, finite element models were used to study the fatigue behavior of Nitinol stents when subjected to cyclic axial compression in different conditions. A specific commercial Nitinol stent was chosen for the analysis and subjected to cyclic axial compression typical of the femoral vascular region. Three different configurations were investigated: stent alone, stent deployed in a tube, and two overlapping stents deployed in a tube. Results confirm that stent oversizing has an influence in determining both the mean and amplitude strains induced in the stent and plays an important role in determining the fatigue response of Nitinol stents. In case of overlapping stents, numerical results suggest higher amplitude strains concentrate in the region close to the overlapping portion where the abrupt change in stiffness causes higher cyclic compression. These findings help to explain the high incidence of stent fractures observed in various clinical trials located close to the overlapping portion.  相似文献   
75.
A satellite communication system is an excellent candidate toprovide broadband integrated Internet services to globallyscattered users. The inter-operation between a satellite systemand the existing terrestrial Internet infrastructure introducesnew challenges at different layers. Automatic Repeat reQuest (ARQ)techniques have been introduced at radio link layer to improve theperformance of Transport Control Protocol (TCP)/IP over wirelessterrestrial links, but these techniques are usually dismissed inpresence of high latency links such as satellite links. In thispaper, we will show that a truncated power control can effectivelyimprove the trade-off delay-residual error after retransmissionsand makes ARQ techniques a feasible solution for error control insatellite links. Furthermore, mobility management issues inpresence of satellite diversity are addressed. Performance of anInter-Segment Hand-Over (ISHO) procedure, in terms of propagationdelay, will be carried out through simulation for different spacesegment configurations.  相似文献   
76.
The thermal cis-trans isomerization of 3′-nitro-4-diethylaminoazobenzene in seven polyethyleneoxides at different molecular weight has been studied kinetically in the temperature range 35–70°C. The dependence of the reaction rate on the polymer polarity and viscosity is discussed. The kinetics of the isomerization of the dye dispersed in the fluid polymeric matrix was found to be a useful probe of the structural features of the polymer.  相似文献   
77.
CRISP-DM is the standard to develop Data Mining projects. CRISP-DM proposes processes and tasks that you have to carry out to develop a Data Mining project. A task proposed by CRISP-DM is the cost estimation of the Data Mining project.  相似文献   
78.
Films obtained from native cellulose synthesized by Acetobacter xylinum and from cellulose obtained from cuproammoniacal solutions (cellulose II) were morphologically characterized by studying the cis-trans isomerization of azo dye Chrysophenine dispersed in their amorphous region. The kinetic measurements of the reaction showed that both films behave as glassy polymers in the temperature range explored (36–66°C). In going from native cellulose to cuproammoniacal cellulose, an increase of the isomerization rate was observed, revealing a more homogeneous distribution and likely larger extent of free volume in the amorphous phase of cellulose II.  相似文献   
79.
80.
Water molecules retained in native cellulose gels obtained from Acetobacter xylinum (AX) were displaced by poly(ethylene glycol)s (PEG) of different molecular weight. The so obtained native cellulose/PEG material, characterized in film form by differential scanning calorimetry, dynamic mechanical thermal analysis and wide angle X‐ray scattering, revealed that strong interactions occur between PEG and cellulose and that the polymer mixture is in the rubbery state at ambient temperature. Moreover, it could be dyed in supercritical carbon dioxide by disperse dyes, thus exhibiting typically lipophilic properties and suitability to be employed as a biocompatible support for lipophilic active species.  相似文献   
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