Temperature-sensitive responses

Background currents of all NO electrodes are sensitive to changes of temperature and pH. Depending on type of electrodes, the effect may be more or less. Clark type NO electrodes are very sensitive to temperature change. The temperature induced response... 

These detectors respond to UV/visible absorbing species in the range 190-800 nm and their response is linear with concentration, obeying the Beer-Lambert law (p. 357). They are not appreciably flow or temperature sensitive, have a wide linear range and good but variable sensitivity. 

Densmore, A. Xu, D. X. Janz, S. Waldron, P. Mischki, T. Lopinski, G. Delage, A. Lapointe, J. Cheben, P. Lamontagne, B. Schmid, J. H, Spiral path high sensitivity silicon photonic wire molecular sensor with temperature independent response, Opt. Lett. 2008, 6, 596 598... 

In this study, we demonstrate new pH/temperature-sensitive polymers with transitions resulting from both polymer-polymer and polymer-water interactions and their applications as stimuli-responsive drug carriers [22-23], For this purpose, copolymers of (Ai,Ai-dimethylamino)ethyl methacrylate (DMAEMA) and ethylacrylamide (EAAm) [or acrylamide (AAm)] were prepared and characterized as polymeric drug delivery systems modulated for pulsatile and time release. 

As stated, the capability of plasma deposits to reduce the access of water to corrosion-sensitive surfaces may be an important motivation for their application in corrosion protection. In order to study this property, Kapton polyimide film was selected as the substrate because of its high inherent permeability to water and its ability to resist elevated temperatures. The response of Kapton film overcoated by PPHMDSO to the permeation of water vapor is shown in Fig. 1. Clearly, the presence of the organo-silicone plasma film greatly reduces water permeation. The magnitude of the effect is much enhanced when plasma polymers are produced at high T and p. 

Microcantilever sensors can be operated in modes in which receptor-based coatings are not needed for example, deflagration of adsorbed energetic molecules can induce a measurable response [10]. Since cantilevers can be made extremely sensitive to temperature using bimaterial effect, calorimetric methods can be carried out on cantilevers with adsorbed molecules [11, 12], Exposing the temperature-sensitive cantilevers with adsorbed species to different infrared (IR) wavelengths in a sequential fashion creates mechanical signatures that mimic the IR absorption spectra of the analyte [13]. 

The PPO block is temperature-sensitive, with an LCST (cloud point) of around 15 °C, whereas the DEA block is pH-responsive. At pH 6.5 and 5°C, both blocks are solvated and the copolymer is molecularly dissolved in aqueous solution. On adjusting the solution pH to pH 8.5, the DEA block becomes deprotonated and hence hydrophobic, leading to the formation of DEA-core micelles at 5 °C. On the other hand, if the pH is held constant at pH 6.5 and the temperature is raised above the LCST of the PPO block, PPO-core micelles are obtained with the weakly cationic DEA chains forming the micelle coronas. Since these new diblock copolymers can exist in two micellar states we have christened them schizophrenic copolymers. ... 

Applications of responsive gels in biotechnology have also been examined. For example, Dong and Hoffman proposed the use of temperature sensitive hydrogels for the immobilization of enzymes in bioreactors [110]. Enzyme activity can be turned on and off by causing the gel to swell or shrink when shrunken, the enzyme activity is turned off, since the pores are blocked to the substrate. Different applications are possible for this system besides enhanced bioreactor performance, including bioassays. 

To identify the rate limiting steps, we carried out a series of parallel experiments one in which we determined the rate of thermal equilibration of cylindrical temperature-sensitive gels in response to different temperature driving forces and the other in which we determined the rate of swelling or shrinking of identical gel samples under identical conditions. 

Our research on responsive gels has been carried out with applications in separations and drug delivery in mind. Except for the slurry dewatering process described in the next section, however, we have not focused on the development of specific applications. One novel idea which we pursued, however, was the me of temperature-sensitive PNIPAAm for the preparative gel electrophoresis, discussed in Sect. 7.2. 

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