Titanium port

Subcutaneous implantable devices are composed of a reservoir component made of stainless steel, titanium, or plastic connected to a polyurethane or silicone catheter (Fig. 6.3). The reservoirs are implanted into the subcutaneous tissues in the chest wall, upper arm, or forearm (Jaques et al. 1992 Foley 1995 Kaufman et al. 1996). The stainless steel ports produce significant artifacts on computed tomography (CT) and magnetic resonance imaging (MRl), and are not often used in the chest wall location. Titanium ports cause only local MRI degradation and plastic ports result in minimal CT... 

The anodes are platinized titanium (titanium plated with 5 microns of platinum) the cathodes are also titanium plated with 2.5 microns of platinum. All gaskets are Viton GF (peroxide grade), and the cell membranes are DuPont Nation 324. Flow through the cells is in parallel using manifolds with /4-inch fluid-flow inlet port orifices to provide equal flow to all cells. 

End plates and ports to be PVDF-lined ductile cast iron. Gaskets to be Viton for agent and Viton GF for energetics. Electrodes to be platinized titanium, pinhole-free, to a thickness of 5 micrometers for the anodes and 2.5 micrometers for the cathodes. 

Titanium was analysed in a mixture of oxides by Sievers et al. [605]. The tetrachloride was produced by reaction with tetrachloromethane at increased temperature. The reagents were sealed in a small capillary, heated, and the capillary was crushed in a modifed injection port of the chromatograph. A stainless-steel column packed with 15% of Histowax on Gas Pak F at 77°C was used. The analysis of standard samples led to a relative error of 1.1%. 

Figure 5 Schematic of a complete multiplexed and integrated instrumental design with eight capillaries. Stars at I, U1, and U2 represent the multiplexed freeze/ thaw valves. The T-assembly is made up of eight pieces of commercial junctions stacked together. These connect to the manifold M1, the SEC (size-exclusion chromatography) purification columns, and the reaction loops. The cross-assembly is made of eight pieces of standard crosses packed together with built-in heaters. V8 is an eight-position motorized titanium valve with a center port. S1 is a two-position motorized PEEK valve. V6 is a six-position motorized PEEK valve. (Reprinted from Ref. 33 with permission.)...

Central venous catheters are reluctantly used as blood access for hemodialysis because of safety concerns and frequent complications, for example sepsis, thrombosis, and vessel stenosis. Nevertheless, 20% or more of all patients rely on atrial catheters for chronic dialysis because of lack of other access. Potentially fatal risks related to central venous catheters include air embolism (1), severe blood loss (2), and electric shock (3). These specific risks have been substantially eliminated by the inherent design and implantation of Dialock (Biolink Corporation, USA). Dialock is a subcutaneous device consisting of a titanium housing with two passages with integrated valves connected to two silicone catheters. The system is implanted subcutaneously below the clavicle. The tips of the catheters are placed in the right atrium. The port is accessed percutaneously with needle cannulas. 

Titanium can sometimes behave in a similar manner to silica, i.e. the oxide deposits physically upon the resin beads. This occurs, for example, at the Port Pirie refinery in Australia which uses the Radium Hill Davidite ore containing titanium. The effect has been considerably alleviated by reduction of the acid usage at the ore leaching stage, thus preventing much of the titanium from reaching the resin. 

Steinfeldt et al. used microchannel reactors to compare the gas-phase oxidative dehydrogenation reaction of propane to propene (C3H6) [17]. The microchannels were made of SS and titanium plates that were stacked tightly together in a graphite housing that provided the inlet and the outlet ports for the reactants and products. 

Many different types of venous-access devices are available. Peripherally inserted central venous catheters (PICCs), which can be made of PU or silicone, are inserted into a vein in the arm rather than in the neck or chest. Nontunneled CVCs are shortterm catheters, made of PU or silicone as well, inserted into the internal jugular, subclavian, or femoral vein. Tunneled CVCs are long-term catheters implanted surgically under the skin. One end of the catheter remains outside the skin and the exit site is typically located in the chest. Passing the catheter under the skin helps to reduce the infection risk and provides stability. Implantable ports are similar to tunneled catheters but are left completely under the skin. They consist in small devices, made of plastic or titanium, inserted beneath the skin and connected to a catheter allowing vascular access. Under the skin, the port has a septum through which drugs can be injected and blood samples can be withdrawn. 

In their work Barrel1 and Ballinger examined two types of electron affinity detectors. The first was of the parallel plate type equipped with a 100 me titanium tritide source, mounted on a Jarrell-Ash Universal 700 gas chromatograph and the second which was of the cylindrical type consisting of a cylindrical 250 me titanium source cathode and a tubular inlet port anode obtained from Wilkins Instrument and Research Corporation. The latter detector required several modifications to obtain adequate response and stability. The most important modification consisted of a heater (Figure 141) to the detector chamber. The electron affinity detector, while not directly sensitive to aliphatic hydrocarbons, can be blocked and rendered totally insensitive by condensation of a heavy and relatively nonvolatile hydrocarbon film on the ionization source. A heater placed around the detector and maintained at a constant temperature of 150 to 180 0 is necessary for the long term stability of this detector. 

As shown in Fig. 5 7(b) the solid polymer electrolyte cell comprises a membrane, fuel cell type, porous electrodes and three further components z carbon collector, a platinized titanium anode support and a cathode support made from carbon-fibre paper The collector is moulded in graphite with a fluorocarbon polymer binder A 25 pm thick platinized titanium foil is moulded to the anode side to prevent oxidation. The purpose of the collector is to bnsure even fluid distribution over the active electrode area, to act as the main structural component of the cell, to provide sealing of fluid ports and the reactor and to carry current from one cell to the next E>emineralized water is carried across the cell via a number of channels moulded into the collector These channels terminate in recessed manifold areas each of which is fed from six drilled ports. The anode support is a porous conducting sheet of platinized titanium having a thickness of approximately 250 pm. The purpose of the support is to distribute current and fluid uniformly over the active electrode area. It also prevents masking of those parts of the electrode area which would be covered by the... 

Epoxies are commonly used on syringe endoscopes, catheters, blood heat exchangers, syringes, as well as dental, surgical and orthopaedic handheld, powered instruments. They are also used in the assembly of stainless-steel or titanium access ports that are implanted beneath the skin of patients who require multiple infusions. 

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