Pressure tuning

Drickamer H G 1990 Forty years of pressure tuning spectroscopy Ann. Rev. Mater. Sc/. 20 1... 

Figure 4.1 Schematic diagram of a coupled column system. The first column (ID) is connected to the second column (2D) tlirough the interface or valve system. The interface can be a diiect coupling, a live T-union, a complex multiport valve, or a thermal or cryogenic modulation system. The stimulus can be the switching of the valve, abalancing pressure to divert flow towards 2D, an added flow that is used in pressure tuning, or the drive mechanism for the modulator. The line to detector 1 will normally be a non-retaining section of column. In a two-oven system, ID and 2D will be in different ovens the dotted line indicates separately heated zones.

Hara K, Bulgarevich DS, Kajimoto O (1996) Pressure tuning of solvent viscosity for the formation of twisted intramolecular charge-transfer state in 4, 4 -diaminophenyl sulfone in alcohol solution. J Chem Phys 104(23) 9431-9436... 

Pressure-Tuning Photochemistry of Metal Complexes in Solution (Eldik... 

Even with this gas-pressure tuning interferometer, the drift of t during a long-time measurement is unavoidable. In addition to the mechanical stability of the interferometer, a feedback loop control of t is necessary for such a long-time... 

The gas-pressure tuning interferometer was used in the experiments described in Section 7.3.2. The mechanical stage type was used in the experiment described in Sections 7.3.3 and 7.4.2. The piezo type was used in the experiment described in Section 7.4.1. It should be noted that the mechanical stage and the piezo types are not installed in a vacuum chamber. 

The interferometric structure around the quarter revival timing discussed above is generated spontaneously by the intrinsic anharmonicity of the potential. Next we will show similar interferometric structures generated by the double-pulse excitation [39]. The pump and control pulses are generated by the gas-pressure tuning interferometer. The double-pulse delay t was stabilized by the feedback loop control. 

Bochniak, D. J., Subramaniam, B. Fischer-Tropsch Synthesis in Near-Critical n-Hexane Pressure-Tuning Effects. AIChE J. 1998,44, 1889- 1896. 

Pressure Tuning Fourier Transform Infrared and Raman Spectroscopy of Anionic Surfactants... 

In this report we describe novel pressure tuning vibrational spectroscopic techniques that can be used to study aqueous surfactant solutions and discuss in some detail two examples of such studies with micellar solutions of anionic surfactants, one using Fourier transform infrared (FT-IR) and another using Raman spectroscopy. 

In view of the small sample size, the optical aperture used for pressure tuning vibrational spectroscopic measurements is also very small. This does not create serious problems for high pressure Raman spectroscopic measurements since the laser beam can be focused to 30-40 pm. Thus, the optical system employed in a standard Raman scattering experiment can be used and no special optical interface is required for the pressure tuning Raman spectroscopic measurements. 

Two representative studies are described here which reveal the type of structural information that can be gained from pressure tuning infrared and Raman spectroscopic experiments with micellar solutions of anionic surfactants. 

Although we have presented here only two examples of pressure tuning vibrational spectroscopic studies with aqueous surfactants, we hope that they are sufficient to demonstrate the uniqueness of pressure as a physical parameter in the investigation of the structural and dynamic properties of aqueous surfactants. For many systems, the vibrational spectra at atmospheric pressure are very similar. Yet, the pressure tuning of these spectra will be able to provide additional information about the structure of the surfactant molecules and about their aggregation in water. 

UV, Photoelectron, Pressure Tuning Spectroscopy, and Laser Flash Photolysis 395... 

Postorino, P., Congeduti, A., Dore, P., Sacchetti, A., Gorelli, F., Ulivi, L., Kumar, A. Sarma, D, D, 2003 Pressure tuning of electron-phonon coupling the insulator to metal transition in manganites. Phys. Rev. Lett. 91, 175501. (doi 10.1103/PhysRevLett.91.175501)... 

Pressure Tuning of Reverse Micelles for Adjustable Solvation of Hydrophiles in Supercritical Fluids... 

Pressure tuning of the polarity of reverse micelles in supercritical ethane... 

IL JOHNSTON ETAL. Pressure Tuning of Reverse Mkdks... 

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