Balloon technique

The balloon technique is often recommended in suitable reactions to maintain an inert and dry atmosphere within the reaction flask. It should be noted however that air and moisture infuse rather rapidly and that this atmosphere may only be maintained for half-an-hour or so. 

Gertsch, P., Fischer, G., Kleber, G., Wheatley, A.M., Geigenberger, G., Sanerbrnch, T. Manometry of esophageal varices comparison of an endoscopic balloon technique with needle puncture. Gastroenterology 1993 105 1159-1166... 

FIG. 1 Balloon technique of oxygenation. About 10 1b oxygen pressure are needed to inflate the pipette bulbs. 

I would like to present some of the background and current activity in balloon-borne infrared astronomy, to examine a number of astronomical objectives in terms of their technical requirements, to describe some of the unique characteristics of ballooning techniques, and to illustrate how the objectives and techniques are mated with some specific examples. 

Percutaneous coronary intervention (PCI) is one of a host of techniques performed by using a catheter inserted via a major limb artery that aims to relieve nanowing of coronary arteries. For example, percutaneous transluminal coronary angioplasty (PTCA) is the classic PCI that uses a catheter-directed balloon to dilate a stenotic coronary artery, and more recent PCIs include stent implantation, rotational atherectomy, and laser angioplasty. 

Milk-Emili, J., J. Mead, J. M. Turner, and L. M. Glauser. Improved technique for estimating pkural pressure from esophageal balloons. J. Appl. Physiol. 19 207-211, 1964. 

Fig. 7.9 Intraeoronary stem cell delivery. The technique is similar to that for coronary angioplasty, which involves over-the-wire positioning of an angioplasty balloon in a coronary artery. Coronary blood flow is transiently stopped for 2-4 min while stem cells are infused under pressure,...

Balloon-Borne Measurements. To illustrate the versatility possible with balloon-borne platforms, the in situ techniques that have recently made important contributions to our understanding of stratospheric reactive trace gases are highlighted. Each technique is based on a fundamentally different physical principle, providing measurements with unique and characteristic spatial and temporal scales. But first the advantages and disadvantages offered (and suffered) in balloon-borne experimentation are reviewed. Some unique facets of balloon behavior that are relevant to a specific experiment are discussed with that experiment. 

Measurements of NO and N02 by Chemiluminescence. Most balloon-borne in situ measurements of NO and NO published to date have been made with the chemiluminescence technique (6, 63,64). Reagent ozone is added to the ambient flow in a reaction chamber, and the chemiluminescence observed from the reaction NO + 03 —> NO + 02 is detected by a photomultiplier tube that views the volume. The amount of light observed is proportional to the amount of NO in the ambient air. N02 is detected by exposing the ambient air going into the detection cell to a strong light source this exposure photolyzes N02 to NO, which can then be detected. 

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