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71.
Glyconanoparticles which present carbohydrate and amino groups motifs at their surface were produced. These particles were highly stable and soluble in aqueous solutions. The presence of the carbohydrate groups also allowed the inclusion of more strongly binding groups, without affecting solubility. The binding of a model DNA, plasmid by these nanoparticles was studied by atomic force microscopy, transmission electron microscopy, and gel electrophoresis. Significant differences between the nanoparticles based on their affinities for the DNA were found, with implications for their potential use as nonviral gene delivery agents.  相似文献   
72.
73.
Many zeranol immunoassay test kits cross-react with toxins formed by naturally occurring Fusarium spp. fungi, leading to false-positive screening results. This paper describes the evaluation and application of recently published, dry reagent time-resolved fluoroimmunoassays (TR-FIA) for zeranol and the toxin alpha-zearalenol. A ring test of bovine urine fortified with zeranol and/or alpha-zearalenol in four European Union National Reference Laboratories demonstrated that the TR-FIA tests were accurate and robust. The alpha-zearalenol TR-FIA satisfactorily quantified alpha-zearalenol in urine fortified at 10-30 ng ml(-1). The specificity-enhanced zeranol TR-FIA accurately quantified zeranol in the range 2-5 ng ml(-1) and gave no false-positive results in blank urine, even in the presence of 30 ng ml(-1) alpha-zearalenol. Zeranol TR-FIA specificity was demonstrated further by analysing incurred zeranol-free urine samples containing natural Fusarium spp. toxins. The TR-FIA yielded no false-positive results in the presence of up to 22 ng ml(-1) toxins. The performance of four commercially available zeranol immunoassay test kits was more variable. Three kits produced many false-positive results. One kit produced only one potential false-positive using a protocol that was longer than that of the TR-FIA. These TR-FIAs will be valuable tools to develop inspection criteria to distinguish illegal zeranol abuse from contamination arising from in vivo metabolism of Fusarium spp. toxins.  相似文献   
74.
75.
New thermodynamic fundamentals for vertical pneumatic conueying are proposed with derivation based strictly on mass conservation and continuum concept. For a 1-D, vertical, steady gas-solid flow, these new mass and energy balances allowed the derivation of a new nondimensional energy factor containing the pressure drop. This energy factor correlated quite well with the difference between the inlet gas velocity and solids terminal velocity, when tested against high-pressure, 15-m-high, vertical pneumatic transport data from Institute of Gas Technology. The energy factor was also checked against atmospheric-pressure data of the 5-m lift line of the Pennsylvania State Uniuersity. The new energy factor covers quite well both the atmospheric- and high-pressure sets of data (923 tests) including two heights, lean- and dense-phase transports, several pipe diameters, broad and narrow particle-size distributions, and different materials. The dissipation terms in gas-solid flow were also clearly identified.  相似文献   
76.
Veneer restorations are well suited for conservative and aesthetic improvement of the anterior dentition. Laboratory fabricated porcelain and composite resin veneers present optimal aesthetics and durability. Although there are disadvantages associated with direct bonding, it provides control of color and contour for the operator, particularly in the case of a single anterior central incisor. Direct/indirect composite resin veneers utilize the advantages of both direct and indirect techniques in reconstruction of restorations with improved physical properties. The learning objective of this article is to review the available composite resins, opaquers, and tints, and present a step-by-step protocol for predictable restoration of discolored anterior dentition with direct/indirect heat-treated composite resin veneers in a single appointment. Patient evaluation, preoperative aesthetic considerations, selection of the restorative composite resins, and the clinical procedure are discussed.  相似文献   
77.
In this work, we present a novel process to produce plasticized PVC articles. Plasticized PVC dispersion resin (dry blend) was extruded and poured into a hot mold. The mold was transferred to a rotomolding machine, where the final geometry was obtained. Formulations using commercial PVC suspension resin and three different types of plasticizers were prepared under different processing conditions. The physical appearance of the articles and the tensile properties of the materials were evaluated.  相似文献   
78.
Zusammenfassung Die laserspektroskopischen Me?methoden laserinduzierte Fluoreszenz und spontane Ramanspektroskopie werden eingesetzt zur Messung der Konzentrationen von Stickoxid, Hydroxyl sowie der chemischen Hauptkomponenten und der Temperatur. Betrachtet wird die thermische Umsetzung von Wasserstoff mit Luftsauerstoff. Es wird die experimentelle Vorgehensweise und Problematik dargestellt. Ebenso wird der Weg der Modellierung und Berechnung turbulenter Verbrennungsvorg?nge am konkreten Beispiel skizziert. Die Annahme chemischen Gleichgewichts stellt sich als ungenügend in der Berechnung der Stickoxid- und Hydroxylkonzentrationen heraus. Eine deutlich bessere Vorhersage wird durch Einführen einer Reaktionsfortschrittsvariablen für das chemische Modell erreicht.  相似文献   
79.
Drying of textile bobbins was carried out on two kinds of laboratory-scale dryers: in a cross circulation drying rig, atmospheric pressure heating air is used, while in the through circulation drying apparatus, the heating air is pressurized before the drying process takes place. In both cases, a bobbin was fitted with seven thermocouples, placed in a plane normal to the bobbin axis but at different radial distances, in order to provide temperature data during the drying process. In cross circulation drying, plots of temperature against time indicated the presence of two moving fronts, one starting from inside the bobbin, another from the outside, while in through circulation drying, similar plots showed the presence of an evaporation front, moving from inside the bobbin to the outside. In both canes, numerical models were developed to simulate the drying processes.  相似文献   
80.
Palatopharyngeal surgery is a therapeutic option for obstructive Sleep Apnea Syndrome (OSAS). This operation is based on the assumption that the soft palate is the principal apneogenic area of the upper airways. The effectiveness of palatopharyngeal surgery and of correcting nasal obstruction (co-adjuvant factor of SAOS), when present, was evaluated. Thirty patients were selected by cephalometry for surgery (3 women, 27 men; age 45.3 +/- 7.5 years). The success rate was 60%, which justifies the inclusion of surgery as a useful option for treating SAOS.  相似文献   
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