Whiteness, coated surface

When dark roofs are heated by the sun, they directly raise summertime building cooling demand. For highly absorptive (low-albedo) roofs, the surface/ambient air temperature difference may be 50°C (90°F), while for less absorptive (high-albedo) surfaces with similar insu-lative properties (e.g., white-coated roofs), the difference is only about 10°C (18 F), which means that cool surfaces can effectively reduce cooling-energy use. 

A near white surface finish corresponds to Swedish standard Sa 2-1/2 or BS4232 second quality. This finish is defined as one from which is removed all oil, grease, dirt, mill scale, rust, corrosion products, oxides remaining coatings, except for a very light shadows of light streak discolouration. At least 95% of the surface shall have the appearance of a white metal surface finish and the remainder shall be limited to light discolouration. 

Penetrant Method. This method does not depend upon radiation interactions with the lest object and is essentially noninstrumental. A special penetrant substance is applied freely on the test object and allowed to work into tight cracks. See Fig. 3. The penetrant is removed from all surface areas and the piece is sprayed with a developer. The developer dries to an even white coating, while the penetrant bleeds up from any flaws through the developer, forming bright-red or fluorescent indications on the white surface. The size of the defect is indicated by the richness of color, speed of bleed-out, and dimensions ohserved. 

In a similar way, a well-adhered surface modification of BC fibers can be achieved with Ti(>2 nanoparticles (with a diameter of about 10 nm) by the hydrolysis of titanium tetraisopropanolate adsorbed onto the fibers. It was observed that the titania-coated surface appears to be dense and have low porosity and to consist of near-spherical grains. By washing with sodium carbonate solution, the TiC>2 films were not removed during neutralization. It seems that the particles have formed strong interactions with BC. The coated membranes showed substantial bactericidal properties under UV radiation and white light (containing a small fraction of UV) conditions, too. This effect is caused by the photocatalytic destruction of the bacterial cells. 

Figure 10. (a) Oriented adsorption of IgG on a pre-coated surface, leading to a biologically more active layer, (b) Prevention of (a) spreading and (b) tilting of adsorbed IgG by pre-adsorbed molecules. The antigen binding sites are represented by the white dots at the top of the F(ab)... 

Ambergris is excreted into the sea along with the whale s other wastes. Due to its low density, it floats in salt water and is sometimes collected from beaches. It comes in a variety of colors, usually gray or brown, and may have a white powdery surface coating. Ambergris has also been collected from whales killed during hunting, or that died and came to rest on a beach. 

Close the vacuum inlet adapter slowly until it is fully shut and observe the flask for a few seconds, if boiling occurs (liquid is condensed to the receiver flask) continue until boiling stops and then lower the flask so that it just touches the surface of the water, lock it in place and boiling should recommence. As the volume of solution decreases, you may need to lower the flask further into the water bath until all the solvent has been evaporated. If a white coating of frost forms on the flask evaporation may stop, because the flask is too cold lower the flask into the water bath to warm it and evaporation should begin again. 

Symptoms Downy mildew infections begin as angular yellow spots on the upper leaf surfaces these spots eventually turn brown. Corresponding white, tan, or gray, cottony spots form on the undersides of the leaves. Downy mildew can also attack young shoots and fruit, forming a white coating. 

Different behaviour is shown by corrosion due to atmospheric moisture, since in this case the reaction products are not removed from the surface because the products are strongly alkaline, the glass decomposition is accelerated, in particular when condensation of moisture is alternated with evaporation. A white coating is formed on the glass surface after longer periods of time. 

The firing of the crucibles is carried to a temperature but little above the temperature of complete dehydration of the clay, usually between 650 to 700°C. Even in muffle kilns some loss of graphite occurs on the surface of the crucibles through oxidation, as is evidenced by the white coating of clay. 

White wood-free paper for laminates is usually one-side coated paper that has been super-calendered to make the outside (coated) surface less permeable. 

The work to be discussed here deals with platelet adhesion to protein coated surfaces. The protein coating, the cells on the surface and the moving fluid adjacent to the surface may be viewed as a system of interacting components. Flow is an important feature of this system since it brings new protein and cells to the system, augments the transport of cells to the surface and can cause the detachment of adherent cells. Each component of the system may influence the conditions of the other components. The variation of the surface concentrations of proteins on a solid substrate continues to be studied and remains a key area of interest. However, the action of immobilized cells on the substrate needs to be examined more carefully as well as their contribution of secreted substances to the fluid phase adjacent to the substrate and to the substrate protein itself Red cells, platelets and white cells may also adhere and detach from the substrate changing its make-up by yet another mechanism. 

There are various methods of assessing the state of fusion of PVC. Intact particle boundaries, coated with stabilisers, etc. are very weak. Consequently, immersing the PVC in a liquid such as methylene dichloride causes the particles to separate, giving rise to a white powdery surface (Fig. 6.20). The wall of the pipe has been chamfered to expose the different layers. Fusion is only complete at the inner and outer surfaces, that experienced the highest levels of shear in passing through the extrusion die. A pipe with this level of fusion would have inferior mechanical properties. The fusion of PVC particles is referred to as gelation. As PVC is mixed in an internal mixer, viscous dissipation causes a steady rise in temperature. Samples are removed at various... 

E.T. ZeUers, R.M. White, Selective surface-acoustic-wave styrene vapor sensor with regen-erable reagent coating, in Proceedings 4th International Conference Solid State Sensor and Actuators, Transducers (1987), pp. 459-461... 

Since it is not practical to measure the surface temperature of individual test specimens, black panel and white panel temperature sensors are used to represent maximum and minimum temperatures attained, respectively, by samples. The panels are thin metal substrates (stainless steel or anodized aluminum) treated on the front surface with a black or white coating that has good resistance to weathering. A thermocouple or other type of temperature sensor is attached to the center of the front or back side, preferentially the latter. The substrate can be either iminsulated, allowing ambient air to circulate on the front and back for maximum cooling, or insulated on the back to simulate specimens exposed on a... 

Accelerated tests such as ASTM B 201 are very useful in evaluating the quality of chromate films on zinc or zinc-coated surfaces. The test proceeds until white corrosion products have formed and should not be allowed to continue until red rust forms. Only the time to formation of "white rust is relevant. The effects of impurities on the corrosion rate of zinc can be determined by humidity testing. 

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