TPS method

Complementary techniques in catalytic chemistry involve temperature programmed (TP) methods where a reaction is investigated by subjecting the catalyst immersed in a reactant, to a temperature ramp. Rates of both reduction and oxidation can be studied. The extent of the catalytic reaction is then plotted as a function of temperature. In TP-desorption (TPD), the desorbed material is detected and plotted against temperature. 

The NPT-TP method [77] locates phase coexistence at a prescribed temperature by finding that value of the pressure for which the chemical potentials of the two... 

Temperature-programmed (TP) reaction methods form a class of techniques in which a chemical reaction is monitored while the temperature increases linearly in time [1, 2]. Whilst several forms of these techniques are currently in use, they are all applicable to real catalysts and single crystals, and have the advantage that they are experimentally simple and inexpensive in comparison to many other spectroscopies. Although interpretation on a qualitative basis is rather straightforward, obtaining reaction parameters such as activation energies or preexponential factors from TP methods, is a complicated matter. 

Castor TP. Methods and apparatus for making liposomes. US patent 5554382, 1996. 

Cellulosic is a family name that applies to a wide group of thermoplastics. They are not synthetic plastics but rather are made from a natui y occurring polymer, cellulose, which is obtained from wood pulp and cotton linters. Cellulose can be made into a film as cellophane or a fiber, rayon, but it must be chemically modified to produce TPs. Because it can be compounded with many different plasticizers in widely varying concentrations, its property range is broad. These plastics are normally specified by their flow, according to ASTM D 569, which is controlled by the plasticizer content. Cellulosics are all processed by conventional TP methods. They include the following types. 

One of the main features of TP methods is the abUity to pattern on nonplanar or flexible surfaces (such as polymer membranes) and on topographies or previously patterned surfaces. The last feature may be repeated (with some processes, indefinitely), creating multilayered 3D structures and hierarchichal structures. 

Catharometer serves for measuring the difference in thermal conductivity between reference gas and the gas that flows through the sample (it is used only in flow systems). This kind of detectors is often used in the variations of temperature-programmed (TP) methods, known as TPO or TPR. 

The basic situation that can be addressed with the TPS method is illustrated in Fig. 7. Here, the stable states A and B correspond to regions in configuration space (or, more generally, in phase space) characterized in terms of the microscopic variables. Each of these regions is stable in the sense that if the system is initialized in the region it will most likely stay inside it for a long time. The two regions... 

The basis of the TPS method is the definition of the ensemble of all reactive trajectories, i.e., the ensemble of pathways that start in A at time 0 and end in B at time T later. (We will return later to the problem on how to specify the time T.) Each trajectory, or path, is represented by an ordered sequence of microscopic states ... 

---