Phase direction

Survey of the patent Hterature reveals companies with processes for 1,4-butanediol from maleic anhydride include BASF (94), British Petroleum (95,96), Davy McKee (93,97), Hoechst (98), Huels (99), and Tonen (100,101). Processes for the production of y-butyrolactone have been described for operation in both the gas (102—104) and Hquid (105—108) phases. In the gas phase, direct hydrogenation of maleic anhydride in hydrogen at 245°C and 1.03 MPa gives an 88% yield of y-butyrolactone (104). Du Pont has developed a process for the production of tetrahydrofuran back-integrated to a butane feedstock (109). Slurry reactor catalysts containing palladium and rhenium are used to hydrogenate aqueous maleic acid to tetrahydrofuran (110,111). 

CNTs, respectively. Thus, in the cylindrical geometry, we may get a result that is not so polarisation sensitive. On the other hand in C o. since all 60 atoms are equivalent, no carbon atom can move in an out-of-phase direction around the C5 axes for either of the two A g modes, so that both modes show similar polarisation behaviours to each other [1]. 

This relatively new trend in PCM manufacturing business amounts to creating a polymeric matrix out of the liquid or gaseous phase directly on the filler surface which has previously undergone special conditioning aimed at generating active polymerization sites on it. 

The reason is that the backspillover ions desorb to the gas phase directly from the three-phase-boundaries or react directly at the three-phase-boundaries (electrocatalysis, A=l) before they can migrate on the gas-exposed electrode surface and promote the catalytic reaction. The limits of NEMCA are set by the limits of stability of the effective double layer at the metal/gas interface. 

Accordingly, for decades scientific investigations have been carried out to achieve the direct fluorination which would be attractive as a one-step synthesis alternative. Although the early reports concerned gas-phase direct fluorinations, the most relevant work in the last three decades was based on contacting fluorine gas with the aromatic compound dissolved in a liquid phase. These attempts at gas/liquid... 

On the other hand, electrospray ionization mass spectrometry (ESMS) has been first combined with electrochemistry at ITIES in order to confirm the stoichiometry of a complex ion transferred into an organic phase directly. ESMS is now becoming a popular and powerful technique not only in chemistry but also in biology, pharmacy, medical science, etc. Electrospray (ES) ionization is exceedingly effective resource for producing gas-phase ions from various solutions which contain any kinds of ion. Thus, ESMS can sometimes give us highly useful information in comparison with electrochemical results. 

Chamoin S, Houldsworth S, Kruse CG, Bakker WI, Snieckus V. The Suzuki-Miyaura cross coupling reactions on solid support. Link to solution phase directed ortho metalation. The Leznoff acetal linker approach to biaryl and heterobiaryl aldehydes. Tetrahedron Lett 1998 39 4179-4182. 

U = metric tensor of the space nc = normal vector in gas-phase direction... 

Radiation techniques, application to the study of organic radicals, 12, 223 Radical addition reactions, gas-phase, directive effects in, 16, 51 Radicals, cation in solution, formation, properties and reactions of, 13, 155 Radicals, organic application of radiation techniques, 12,223 Radicals, organic cation, in solution kinetics and mechanisms of reaction of, 20, 55 Radicals, organic free, identification by electron spin resonance, 1,284 Radicals, short-lived organic, electron spin resonance studies of, 5, 53 Rates and mechanisms of solvolytic reactions, medium effects on, 14, 1 Reaction kinetics, polarography and, 5, 1... 

At the beginning stage of dehydrogenation, the substrate organic hydride is adsorbed onto the catalyst surface from the liquid phase directly and easily. Catalytic reaction processes will succeed it, until the surface sites are filled with the adsorbed reactant and products. Once product desorption starts to form and grow a bubble, product readsorption becomes unfavorable due to the increment of translational entropy of the product molecule in the bubble, if compared with that in the solution, shifting the adsorption equilibrium for the product and suppressing its effect of rate retardation. 

Fig. 4.8. (a) The measured (squares) and predicted (thick lines) intensity ratio r(q) between harmonics from H2 and that from D2 molecules as functions of harmonic order q. tqm and rcM are the predictions with and without quantum effect for nuclear dynamics see text, (b) The measured (squares) and predicted (thick line) relative phases between harmonics from H2 and those from D2 molecules as functions of harmonic order q. Measuring the relative phases directly corresponds to observing the nuclear motions, i.e., the nuclear displacement of H2 Aii1 2 (right axis) as a function of excursion time r (superior axis). For (a) and (b), vertical and horizontal errors represent SEM for 800 laser shots and those from quantum mechanical uncertainty [27]... 

Radical addition reactions, gas-phase, directive effects in, 16, 51... 

MALDI is a method that allows for vaporization and ionization of non-volatile biological molecules from a solid-state or liquid phase directly into the gas phase. The presence of a solid or liquid matrix (around 1 part in 100-50,000), which strongly absorbs the laser radiation, spares the smdied species from degradation, by protecting them from the harsh effects of the laser. It results in the detection of intact molecules... 

These routes rely on vapor phase preparation of catalysts by deposition of metal precursors onto carbon or by direct formation of the catalyst in the vapor phase. Direct vapor deposition of volatile molecular precursors such as acetylacetonate complexes onto carbon has been demonstrated by Sivakumar and Tricoli for PtRu and PtRuIr. ... 

Oxidation of ethyl alcohol was one of the two important commercial routes to acetaldehyde until the 1950s, The other, much older route was the hydration of acetylene. The chemical industry was always after a replacement of acetylene chemistry, not just for acetaldehyde production, but all its many applications. Acetylene was expensive to produce, and with its reactive, explosive nature, it was difficult to handle. In the 1950s, acetylene chemistry and the ethyl alcohol oxidation route were largely phased out by the introduction of the liquid phase direct oxidation of ethylene. Almost all the acetaldehyde produced uses the newer process. 

Different maps were calculated by inverse Fourier transformation of the amplitudes and phases of all reflections at different stages of image processing. Lattice averaged maps were obtained from the amplitudes and phases directly as extracted from the images, before the CTF correction and imposing the S5mimetry. 

In a single HRTEM image, it is difficult to measure atomic positions with a high accuracy especially next to an interface due to contrast delocalization. However, the delocalization is removed in the exit wave function and the maxima in the reconstructed phase directly correspond to the center of the atomic positions. The atomic positions can, therefore, be measured with a... 

An important issue requiring future work is the consideration of anisotropic thermal transport since the thermal conductivity has an order of magnitude difference between the in-plane and through-phase directions as mentioned earlier. 

One way that contaminants are retained in the subsurface is in the form of a dissolved fraction in the subsurface aqueous solution. As described in Chapter 1, the subsurface aqueous phase includes retained water, near the solid surface, and free water. If the retained water has an apparently static character, the subsurface free water is in a continuous feedback system with any incoming source of water. The amount and composition of incoming water are controlled by natural or human-induced factors. Contaminants may reach the subsurface liquid phase directly from a polluted gaseous phase, from point and nonpoint contamination sources on the land surface, from already polluted groundwater, or from the release of toxic compounds adsorbed on suspended particles. Moreover, disposal of an aqueous liquid that contains an amount of contaminant greater than its solubility in water may lead to the formation of a type of emulsion containing very small droplets. Under such conditions, one must deal with apparent solubility, which is greater than handbook contaminant solubility values. 

The differential volatilization of neat kerosene components from a liquid phase, directly into the atmosphere during volatilization up to 50% (w/w), is presented in Fig. 8.8. Ten kerosene components were selected, and their composition was depicted as a function of gas chromatograph peak size (%), which is linearly related to their concentration. It may be seen that the lighter fractions evaporate at the beginning of the volatilization process. Increasing evaporation causes additional components to volatilize, which leads to a relative increase in the heavier fractions of kerosene in the remaining liquid. 

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