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41.
Juan Carlos Benítez Carlos A. Giúdice Vicente J. D. Rascio 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(8):387-394
This paper discusses the bioactivity of antifouling paints based on organotin toxicants, such as tributyltin fluoride (TBTF) and triphenyltin fluoride (TPTF). These compounds were used alone or mixed as the main toxicant in formulations. The use of TPTF or mixtures of TPTF and TBTF, with vinyl binders, led to paints with satisfactory bioactivity during a 24 months immersion period. With the same binders, TBTF alone provided only 12 months of antifouling protection. The correlation coefficients calculated from the fouling attachment values and the rosin content in the binder showed that the bioactivity of the tested formulations depended on the solubility of the toxicant in sea water and on the composition and solubility of the binders. 相似文献
42.
B. Dagens A. Martinez D. Make O. Le Gouezigou J.-G. Provost V. Sallet K. Merghem J.-C. Harmand A. Ramdane B. Thedrez 《Photonics Technology Letters, IEEE》2005,17(5):971-973
Among the new semiconductor materials for telecom devices, the GaInNAs-GaAs structure presents interesting properties for low-cost applications, like high differential gain and high T/sub 0/. Another key aspect of the performance is the behavior of the GaInNAs-GaAs based lasers under high bit rate direct modulation. Here, we demonstrate the dynamic capabilities of GaInNAs-GaAs three-quantum-well ridge structure through 2.5-Gb/s directly modulated laser emission and transmission on standard fiber, in the temperature range 25/spl deg/C-85/spl deg/C. Besides transmission is demonstrated up to 10 Gb/s at 25/spl deg/C on the same fiber, without penalty and bit-error-rate floor. 相似文献
43.
44.
Synthesis of oleyl oleate as a jojoba oil analog 总被引:2,自引:0,他引:2
N. Sánchez M. Martinez J. Aracil A. Corma 《Journal of the American Oil Chemists' Society》1992,69(11):1150-1153
Synthesis of a wax ester analog of jojoba oil was accomplished from oleic acid and oleyl alcohol with a zeolite as catalyst.
A full 23 factorial design at two levels has been used in the synthesis. The variables selected were temperature, reduced pressure
and initial catalyst concentration. The most important variable within the range studied was temperature. Reduced pressure
had a negative influence, and initial catalyst concentration showed a positive influence on the process. A response equation
has been determined for the yield of ester. The properties of the synthesized product are similar to those of natural jojoba
oil. 相似文献
45.
Francisco J. Collado Eduardo Sevilla Carlos Valcárcel 《American Institute of Chemical Engineers》2002,48(5):1100-1108
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
46.
47.
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
48.
Dipl.-Phys. Andreas Neuber M. Sc. Guenther Carlos Krieger Dipl.-Ing. Markus Tacke Prof. Dr.-Ing Johannes Janicka 《Forschung im Ingenieurwesen》1996,62(7-8):188-194
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
49.
R Martinez A Saponaro R Russo G Dragagna N Leopardi L Santoro E Martelli 《Canadian Metallurgical Quarterly》1993,35(1):9-11
Cytokines are central to the development of effective immunity against microbial pathogens and their beneficial effects in the control of a variety of infections of man and animals are well-documented. However, it appears that cytokines may also have detrimental effects in infections by actually enhancing microbial growth. These observations emphasise the fact that many successful pathogens possess mechanisms enabling them to evade the immune response and that caution needs to be exercised in using cytokines as therapeutic agents to control infections in various human diseases. 相似文献
50.
Munro A. Guelen E. Deguine M. Melpignano G. Martinez A. 《Communications Magazine, IEEE》1998,36(2):118-126
The ACTS program is moving the results of the R&D of the parent RACE program nearer to realization through technology and user trials. Particularly in the mobile domain of ACTS, several projects have been investigating the user dimension in the context of the third-generation Universal Mobile Telecommunications Service. Results so far suggest many opportunities to broaden participation, exploit the inherent benefits of the mobile environment, and take advantage of the enormous improvements in wireless communications to realize the potential of global multimedia mobility. This article considers the needs of users for mobile multimedia applications and the consequences of those needs on the equipment, supporting services and teleservices, and communications bearers 相似文献