Polycarbonates Transparent

For on-site measurement from grab sampling, a compact optical device with disposable strips for BOD determination has been developed [36]. The system includes three pairs of light-emitting diodes and photodiodes, and the disposable strips are made of inexpensive, transparent polycarbonate plates, where Pseudomonas fluorescens is immobilized. Using the 2,6-dichlorophenol-indo-phenol sodium salt as chromophore, a linear relationship was observed between the bioluminescence of the exposed strip and the BOD value. 

For a two-year outdoor exposure of transparent polycarbonates, the retention of impact strengths can be, for example ... 

In recent years, the use of transparent fuel cells has increased substantially due to the need for a better understanding of liquid water accumulation on the surface of the DLs and flow through the FF channels. In most transparent cells, either the cathode or the anode (or both) has transparent polycarbonate end plates that act as windows and sit on top of the corresponding FF plates. These plates are normally thin and made out of metal, such as stainless steel or gold-plated brass, and their thickness is equal to the depth of the FF channels (i.e., the charmels are machined all the way through the plate). Thus, the transparent end plate also acts as part of the charmels. 

Another example of thin films showing metallic transport properties down to liquid helium temperature is 0-(BET-TTF)2Br.3H2O, where bilayers are grown on transparent polycarbonate substrates (Mas-Torrent et al, 2001). The bilayers are... 

A numerically controlled mill fabricated trenches and through holes at the ends of the trenches in a thin, colorless, polyacrylic acid plate [26], This thin plate was bonded to a more rigid, transparent polycarbonate base plate with U V-curing optical adhesive. The through holes in the plate were connected to holes in the base plate, thereby forming one conduit. The latter holes did not penetrate the base plate, but rather were connected to cross-type arranged borings. Thereby, fluid connections could be attached to the side of the base plate. 

Two families of transparent polycarbonate-silicone multiblock polymers based on the polycarbonates of bisphenol acetone (BPA) and bisphenol fluorenone (BPF) were synthesized. Incorporation of a 25% silicone block in BPA polycarbonate lowers by 100°C the ductile-brittle transition temperature of notched specimens at all strain rates silicone block incorporation also converts BPF polycarbonate into a ductile plastic. At the ductile-brittle transition two competing failure modes are balanced—shear yielding and craze fracture. The yield stress in each family decreases with silicone content. The ability of rubber to sustain hydrostatic stress appears responsible for the fact that craze resistance is not lowered in proportion to shear resistance. Thus, the shear biasing effects of rubber domains should be a general toughening mechanism applicable to many plastics. 

Therefore, the hydrodynamic behavior of gas and liquid in countercurrent flow has been studied in single tubes provided with internal fins. The tubes were made of transparent polycarbonate to allow visual inspection and video recording of the phenomena observed. The tubes were typically 1 m long and were mounted in a vertical position. Liquid was fed to the top end of the tube, while gas was fed in at the bottom end. 

Additionally, a few visualization experiments were performed by replacing the top aluminum plate by a clear transparent polycarbonate plate. In these experiments, movies of the flow were captured using a high speed CCD camera. The camera was capable of capturing at 1220 frames/sec. 

The cells were harvested by centrifugation and layered on agar-medium into two plastic devices, each provided with five cell chambers. The samples were covered with transparent polycarbonate plexiglas. The containers were sealed to avoid material loss during space flight. 

T. Wydeven developed a plasma process that significantly improves the hardness of optical lenses and, consequently, leads to greater scratch resistance (7. Vinyl-trimethoxysilane films were deposited on transparent polycarbonate lenses by plasma polymerization. The adherent, clear films protect the substrate from abrasion and also serve as antireflection coatings. Post-treatment of the vinyltrimethoxysilane films in an oxygen glow discharge fui ther improved the abrasion resistance. 

Since its release in 1982, the compact disk has taken the world by storm, and billions of CDs have been manufactured [5, 6]. Most of them are of the readonly memory (ROM) type, made from transparent polycarbonate (see Chart 12.1) and providing almost perfect resolution. 

The complex three-layer membrane of Bangkok Airport s membrane roof is illustrated in Fig. 12.9. Here and as explained before, the high and lasting solar reflection of 70% of the outer waterproof PTFE/glass layer is also an important feature. To improve the acoustic properties of the roof, an additional middle layer has been included which consists of a cable net covered with transparent polycarbonate (PC) sheets. This, in conjunction with the translucent inner membrane liner, acts as a baffle. Figure 12.10 provides an interior view of the concourses with the innovative membrane envelope. 

The work to be described which ejecta production during failure ago but it was never published, transparent polycarbonate adherends He then loaded them in tension propagation of failure with a movie... 

Besides bromine and chlorine, there are a small number of fluorinated ffame retardants. Potassium perffuorobutane sulfonate has been promoted by 3M as a replacement for the brominated flame retardants traditionally used in transparent polycarbonate. It had previously been marketed by Bayer for the same purpose, but the patent had expired. 

Still another important area of use for transparent polycarbonates is in food-contact apphcations. This category shares similarities with the medical market in that it requires agency approvals and has restrictions on... 

In the CD, digital information is stored on a transparent polycarbonate disc in the form of microscopic indentations in the surface. The pitted surface is metallized for laser beam reflection and then coated with a protective lacquer. The laser beam enters from below (see Fig. 8.24). When the beam hits a pit there is no reflection when it hits a flat element between the pits it is reflected. The no-reflection/reflection sequence delivers a series of zero/one signals to a photodetector which converts the digital information to analogue music signals. 

Glass headlight lenses have been replaced almost completely by transparent polycarbonate (PC) plastics. These PC plastics are designed to resist high levels of heat and shattering, and they can be molded into almost any shape. Another choice for this market is the use of acrylic plastics. 

Figure 5.47 Crazes are typical aging phenomena on the surface of transparent polycarbonate (basis-stabilized) after weathering under wet conditions from left to right unweathered, 42 days, 56 days, 168 days weathering [671]...

While the BP formed from diphenyloctatetraene is stable for several hours at room temperature, the p,p -N,N-dimethylamino substituted tetraene is stable for several days in solutions in contact with air. The formation of the P (- - ) and BP (-H +) charge states for a variety of substituted diphenylpolyenes is reviewed in Ref. 18, where the origin of the observed transitions is discussed in detail. Dianthracenylpolyenes form extremely stable bipolaronic dications that are stable for several months in solution or as optically transparent polycarbonate composites [7,12]. This dramatic stability enhancement has been rationalized on the basis of aromatic stabilization of the quinoid intermediate and is illustrated in Scheme 4. 

Transparent materials are needed and used as covers for windows, lighting and signage. The transparent dust covers for windows currently in use on cotmnercial aircrafts are typically made of a transparent polycarbonate... 

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