Drop-casting process

Direct chill casting is the pouring of molten aluminum into a water-cooled mold. Contact cooling water is sprayed onto the aluminum as it is dropped into the mold, and the aluminum ingot falls into a water bath at the end of the casting process. 

Zhao et al. prepared magnetite (FesO nanoparticles modified with electroactive Prussian Blue [44]. These modified NPs were drop-cast onto glassy-carbon electrodes. They observed the redox processes commonly observed for PB (similar to that seen in Figure 4.8), and also demonstrated that the Prussian White material produced by PB reduction at 0.2 V served as an electrocatalyst for Fi202 reduction. They also prepared LbL films in which PB NPs and glucose oxidase were alternated between PD DA layers [99]. These were demonstrated to act as electrocatalysts for Fi202 reduction. Based on the ability to sense the product of the enzymatic reaction, these structures were shown to act as glucose sensors. 

In the slip-casting process a capillary pressure drop AP between the support pores (with radius r in case of cylindrical capillaries) and the liquid drives the liquid into the support and through the formed gel layer. This is schematically shown in Fig. 8.3. The total pressure drop AP. (generated by the support pores)... 

As mentioned previously, mesoscale crystalline morphologies and molecular orientation of HT-PATs in solution-deposited films can be controlled through different solution-processing methods and subsequent thermal treatments [15,17,23,35,36,44,59,89]. Figures 5.2.18 and 5.2.19 represent typical examples for tunable crystalline morphologies and molecular orientations of HT-PHT in solution-deposited films. First, in terms of mesoscale morphologies, HT-PHT (M = 18.8 kDa) films drop-cast from CHCI3 show weU developed nanofibrils interconnected with each other, while the spin-cast... 

Fig. 1 Process for preparing S-IPN films (a) solution is drop cast onto treated glass (b) solvent is allowed to evaporate and the RTV silicone cures at room temperature (c) film is peeled off of the glass substrate (d) film is stretched biaxially by 100 x 100% (e) HTV silicone is cured at 180°C for 30 min (f) film is relaxed and some prestrain is preserved. Reproduced with permission fi om [34]...

The low-pressure die-casting process involves holding the molten metal to be cast in a crucible around which are arranged the heating elements necessary to keep the metal molten. The crucible and elements are contained inside a sealed pressure vessel in the top cover of which is a riser tube whose lower end is immersed in the molten metal. Low-pressure air (0.75 bar to 1.0 bar) is introduced into the crucible above the surface of the molten metal and forces the metal up the riser tube and out through the top end. This top end is attached to the bottom or fixed half of the die, which is designed to allow air to escape as the molten metal enters. When the metal has solidified in the die, which is aircooled, the air pressure is released and the remaining molten metal in the riser tube drops. 

Of notable significance to the discussion of UV-vis studies of PAT solvation is the work of Fraleoni-Morgera et al. [184]. They have found that the addition of a surfactant. Tween 80, can solubilize PHT in water. This process was studied using UV-vis by treating the polymer as its own optical probe. The spectrum of the aqueous polymer microemulsion shows a redshift with respect to the same polymer in THF, and vibronic structure similar to that of a drop cast film of the same. The results reveal that while the polymer is in solution, it is conformationally ordered due in part to the formation of aggregates and the interaction of the side chains with the solvent. 

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