The materials under consideration were silica nanoparticles co-doped with a rare earth element and another metal element; also nanoparticles having a magnetic oxide core and a shell comprising a rare earth element or a metal. This process is schematically shown in Fig. (8). Note that the process and the apparatus have two aspects. From the bottom of the chamber either a spray of the precursor solution or hydrogen gas enters the chamber, where the former process is a FSP process similarto that of Ju and Qin [45]. Other precursor materials may be placed inside the chamber in one or more crucibles. To better understand these two aspects of this invention, the following two examples are instructive.As an example, Eu(TMHD)3 and sodium were placed in two crucibles inside the furnace, and hydrogen gas was introduced to the chamber, as well. Hydrogen entrained the saturated vapors of Eu(TMHD)3 and sodium. This gas mixture was then ignited when it entered the flame. The starting materials decomposed in the flame forming corresponding oxides and further formed silica glass nanoparticles that contained europium. As another example, an ethanol solution containing Eu(NO3)3 and Y(NO3)3 was sprayed and introduced to the chamber from the bottom inlet. Hydrogen gas was also introduced to the chamber from the same inlet. The droplets were ignited once they entered the
diffusion flame.
Strobel et al. [47], invented a process for the production of nanoparticles comprising a non-segregated submicron mixture of individual nanoparticles by flame spray pyrolysis. In this method, two spray nozzles are connected to two precursor reservoirs at an angle Fig. (9). The reservoirs are filled with two different precursors. The precursors are sprayed and ignited to produce two spray flames oriented at an angle with respect to each other. Depending on the distance and angle between the nozzles, some portion of the two flames may overlap or at least the vapors of the two precursors will mix to produce multicomponent particles.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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