Spray microscopic images

The invention of sticky notes occurred over a period of about 10 years and involved a great deal of serendipity. The adhesive for Post-it Notes was discovered by Dr. Spencer F. Silver of 3M in 1968. Silver found that when an acrylate polymer material was made in a particular way, it formed crosslinked microspheres. When suspended in a solvent and sprayed on a sheet of paper, this substance formed a sparse monolayer of adhesive after the solvent evaporated. Scanning electron microscope images of the adhesive show that it has an irregular surface, a little like the surface of a gravel road. In contrast, the adhesive on cellophane tape looks smooth and uniform, like a superhighway. The bumpy surface of Silver s adhesive caused it to be sticky but not so sticky as to produce permanent adhesion because the number of contact points between the binding surfaces was limited. 

FIGURE 16.2 The MF microcapsules (a) microscope image of the aqueous slurry and (b) SEM image of the spray dried powder. 

FIGURE 25.3 Microscopic images of carnauba wax microparticles produced by spray congealing under following conditions melt temperature 115°C, pneumatic spraying system with air pressure 1 bar, air nozzle internal diameter 1 mm (unpublished data). 

Figure 10.10 Scanning electron microscope images (a) and (b), showing morphology of cellulose nitrate biopolymer spray cast from cellulose nitrate/solvent/biolubricant ternary system (c) measured static water contact angle and hysteresis on the biopolymer coating as a function of biolubricant/solvent weight ratio [18].

Fig. 6.2 Microscope images of spray-dried powder (maltodextrin, C MS, drying temperature 200°C). (a) Non-foamed (b) Foamed.

In order to analyze the effect particles have on superheated atomization, suspensions consisting of deionized water and glass beads are sprayed. The polished glass beads are Silibeads Type S (Size 0-20 pm). The solids concentration is set to 5,15, and 25 wt%. The volume density and cumulative distribution of the beads are given in Fig. 16.9. The major part of the particles is smaller than 10 pm. The beads have a smooth surface as shown in the microscope image in Fig. 16.9. 

Collection Techniques. The simplest mechanical method for normal liquid droplets is the slide collection slide sampling) or impression method. This method was extensively used three decades ago, and has been rarely employed since then. In this method, when the slide is exposed to a spray, droplets impinging on it make impressions. The impressions are then observed and measured usually using a Quantimet image analyzer, although a microscope fitted with a traversing scale may be used for the measurement. The measured data are subsequently converted to actual droplet sizes based on a correction factor proposed by May.[659]... 

Microstructural analysis of suspension plasma sprayed Ti02 coatings by Raman spectroscopy and transmission electron microscopy correlated well with results obtained by XRD. The anatase content in the coatings varied between 10 and 22 mass%, dependent on spraying parameters. Raman spectroscopy enabled the imaging of the spatial 2D-distribution of the rutile and anatase (Podlesak et al., 2008). Transmission electron microscope enabled to visualise the contact areas between the lamellae inside sprayed coatings as well as the columnar growth of crystal inside the lamellae. 

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