TG/FT-IR: An Analysis of the Conditions Affecting the Combined TG/Spectral Response

The results of TG/FT-IR measurements performed on hydrated beta-cyclodextrin at different heating rates and with different carrier gas fluxes are reported. It is shown that the shape of the spectral curve and the its degree of matching with the DTG curves depend on both the TG heating rate and the carrier gas flow rate

Fourier transform-infrared study of the adsorption of unsaturated and aromatic hydrocarbons on the surface of \u3b1-Fe2O3. Part III. Toluene, ethylbenzene and styrene

IR spectra of toluene, ethylbenzene and styrene adsorbed on pressed discs of hematite between room temperature and 400\ub0C are described. Mechanisms of adsorption and transformation are discussed and compared with those reported on the basis of kinetic measurements of ethylbenzene dehydrogenation on iron oxide catalysts. \ua9 1985 Akad\ue9miai Kiad\uf3

Fourier transform-infrared study of the adsorption of unsaturated and aromatic hydrocarbons on the surface of α-Fe2O3. II. Benzene

none4Benzene adsorption on α-Fe2O3 in the temperature range 300-673 K has been studied. Two different molecular adsorbed forms can be distinguished due to their spectroscopic behavior and the different equilibrium pressures needed for their formation. The more stable form, in which the benzene molecule is π-bonded on exposed metal cations, slowly transforms at room temperature into combustion products. This process is inhibited by the presence on the surface of the second form of adsorbed benzene. © 1984.G. Busca; T. Zerlia; V. Lorenzelli; A. GirelliBusca, Guido; T., Zerlia; V., Lorenzelli; A., Girell

How solar energy and electrochemical technologies may help developing countries and the environment

The policies of curbing CO2 emissions have worked poorly on a global scale and an economically sound proposal of bringing electric power to Europe from an Algerian solar hub has just been dismissed. With reference to the Algerian - European relationships, we analyze the broad context where an environmental policy benefitting both developing and developed countries can be put in place. We then discuss the connection between anthropogenic CO2 emissions and acidification of Oceans along with a geo-engineering proposal aimed at solving these pressing problems with large-scale solar-powered chloralkali plants. While the cost of sequestering a ton of CO2 with dedicated chloralkali plants is unacceptably high, it is economically and environmentally sound to replace an existing European Cl-2 plant (consuming fossils) with a solar-powered plant in Algeria. If the Algerian plant uses a new, more efficient chloralkali process, it will be competitive with existing European plants even at the current low market value of the carbon emission credits. We finally explore the possibility of coupling Cl-2 production with CO2 reuse and syngas production through a novel electrochemical process

Factors Affecting the Spectral Response in a TG/FT-IR Experiment

We discuss situations in which thermogravimetric / Fourier Transform infrared plots are obtained which differ substantially from the expected ones. The most common of these situations involves samples that release atmospheric components like water and CO2 at low temperatures.It is shown that those situations are mainly due to the effect of the purging action of the carrier gas

ACTIVITY AND SELECTIVITY IN CARBON-MONOXIDE HYDROGENATION OVER RHODIUM SUPPORTED ON PURE ZIRCONIA AND ON K-DOPED, P-DOPED, AND Y-DOPED ZIRCONIA

Catalysts for the CO/H2 reaction were prepared by supporting Rh4(CO)12 on pure ZrO2, with different phase compositions, and on ZrO2 doped at the surface or in the bulk with K20, P205, or Y2O3, and by decomposing the supported carbonyl in a hydrogen stream at 523 or 823 K. The catalysts were characterized by XRD, oxygen and hydrogen chemisorption, TPR, FT-IR/PAS, and catalytic activity measurements both in temperature-programmed experiments and in isothermal condition runs, at atmospheric pressure and with different feed compositions. The phase composition of the support or the doping procedure (bulk or surface) has a minor effect on the physicochemical properties and catalytic activity. Also, the various doping agents, with the exception of K20, have minor effects. K2O doping decreases the activity and changes the selectivity of Rh/ZrO2 in the CO/H2 reaction, favoring the formation of oxygenated compounds. Activation at high temperature (823 K) decreases the activity but does not change the selectivity of the catalysts. A significant influence of the feed HZ/CO ratio on activity and selectivity has been found: activity decreases with Hz/CO ratio and selectivity to oxygenates increases. The role of the various parameters investigated is discussed. © 1990

Solid State Interaction Study on the System Polyvinylpyrrolidone-XL/Trimethoprim

The interaction between cross-linked polyvinylpyrrolidone and trimethoprim has been studied by differential scanning calorimetry, scanning electron microscopy, Fourier Transform Infrared Photoacustic Spectroscopy

From Chemical bonds to macroscopic properties: Contributions of spectroscopies.

The contribution of different kind of spectroscopic methods in describing the macroscopical properties of substances starting from the identification of the chemical bonds, their natire and the surround of the atoms is discussed