INDEX technological improvements

Other areas of IPN application cover circuit boards (Tate and Vamell 1989 Takahashi et al. 1996) and, via gradient IPN technology, improved optical fibers (Bukhbinder and Kosjakov 1996). This last works by having a gradient refractive index firom the axis to the surface, curving the light back away from the surface and... 

Flotation results show that SF-D technology can improve the separation index. Take the SF-D flotation of hematite in Marquette mill, America, the separation index is improved, and the reagent dosage is reduced. The related flotation results can be seen from Table 15.3. And the reagent system is as follows ... 

Improvements in asthma treatment include the development of more effective, safer formulations of known dmgs. The aerosol adrninistration of P2-agonists or corticosteroids results in a decrease in side effects. Also, the use of reUable sustained release formulations has revolutionized the use of oral xanthines which have a very narrow therapeutic index (see Controlled release technology). For many individuals, asthma symptoms tend to worsen at night and the inhaled bronchodilatots do not usually last through an entire night s sleep (26,27). 

The LDPE reactor is sometimes termed heat transfer limited in conversion. While this is true, the molecular weight (or melt index)—conversion relationship is not since this work shows that a selected initiator can allow conversion improvements to be made under adiabatic conditions for a specified molecular weight. The actual limitation to conversion is the decomposition temperature of the ethylene and given that temperature as a maximum limitation, an initiator (not necessarily commercial or even known with present initiator technology) can be found which will allow any product to be made at the rate dictated by this temperature. Conceptually, this is a constant (maximum) conversion reactor, runnirg at constant operating conditions where the product produced dictates the initiator to be used. 

The combination of light-transmitting optical cable and miniature silicon sensors has resulted in the development of a new measurement technology for various industrial processes. Three variables may be measured with tins technique—temperature, pressure, and refractive index. The new systems are immune to electromagnetic and radio-frequency interference, they provide more accuracy in electrically noisy environments, and their miniature size improves response and causes minimal process disturbances. 

Very often baseline problems are related to detector problems. Many detectors are available for HPLC systems. The most common are fixed and variable wavelength ultraviolet spectrophotometers, refractive index, and conductivity detectors. Electrochemical and fluorescence detectors are less frequently used, as they are more selective. Detector problems fall into two categories electrical and mechanical/optical. The instrument manufacturer should correct electrical problems. Mechanical or optical problems can usually be traced to the flow cell however, improvements in detector cell technology have made them more durable and easier to use. Detector-related problems include leaks, air bubbles, and cell contamination. These usually produce spikes or baseline noise on the chromatograms or decreased sensitivity. Some cells, especially those used in refractive index detectors, are sensitive to flow and pressure variations. Flow rates or backpressures that exceed the manufacturer s recommendation will break the cell window. Old or defective source lamps, as well as incorrect detector rise time, gain, or attenuation settings will reduce sensitivity and peak height. Faulty or reversed cable connections can also be the source of problems. 

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