Regeneration studies

Soni MG, Mehendale HM. 1991b. Protection from chlordecone-amplified carbon tetrachloride toxicity by cyanidanol Regeneration studies. Toxicol Appl Pharmacol 108(1) 58-66. 

The adsorption bed could be operated vertically or horizontally and was surrounded by a muffle furnace for the regeneration studies. Various lengths of bed were employed and the adsorbent in the bed was support ed at both ends with porcelain saddles. 

When operated in a horizontal mode, inlet and out let risers were located at SI and S2 to insure complete flooding of the adsorption bed. Septa at SI and S2 also provided access for inlet or outlet liquid samples that could be analyzed. When regeneration studies were being performed, an internal thermocouple was used to monitor the adsorption bed temperature and the dry nitrogen regeneration gas was passed through the bed by switching valve VI. 

Nicol, C., Carnes, B., Margot, L., Ramain, L. 2000. DIAMEX solvent regeneration studies. ATALANTE 2000, Avignon, France, October 24—26, pp. 3-22. 

Slawyk, G., Raimbault, P., and Helquen, S. L. (1990). Recovery of urea nitrogen from seawater for measurement of N abundance in urea regeneration studies using the isotope dilution approach. Mar. Chem. 30, 343—362. 

Kristiansen, S., and Paasche, E. (1989). An improved method for determining relative N abimdance in ammonium regeneration studies by direct diffusion. Mar. Ecol. Prog. Ser. 54, 203—207. 

Lee Y. W., Kim H. J., Choi D. K., Yie J. E., and Park J. W., Temperature programmed reaction and regeneration studies of NOx over potassium hydroxide-containing activated carbon. Environ. ScL Technol, in revision. 

Most of the research reported in the literature was oriented towards analyses of product distribution, influence of operating conditions and reaction mechanisms. Recently, spectroscopic characterization of coke deposits formed on Y-zeolite catalysts was reported (13,14), and Stocker et al presented regeneration studies of the EMT catalyst, by heating in air up to 600°C (15). 

The industrial oxidative regeneration was performed under the optimized condition determined by the laboratory regeneration study. Table 2 summarizes the results of three cycle use of the same catalyst for an LGO HDS application, made possible by the successful regenerations. 

Another example of an experiment showing the sizes of the physiologically defined minicolumns is the nerve regeneration study carried out by Kaas et al. (1981). These experimenters made an initial electrode penetration of the somatic sensory hand area in a monkey s neocortex in a direction more or less parallel to the surface of the cortex and showed that over a considerable distance the same modality type is observed. They then sectioned the median nerve and allowed time for the nerve to regenerate and re-innervate of the skin. The recording experiment was then... 

The activation-regeneration study performed with sample c comprises three steps 1) toluene oxidation at 440 °C, 2) toluene flow interruption followed by heating of the reactor bed in air flow up to 490 °C 3) cooling of the reactor bed down to 440 °C followed by toluene oxidation. In figure 3 the temperature profile and the evolution of toluene conversion during these three steps deactivation - regeneration - deactivation, is shown. The comparison... 

Prior studies utilizing adsorbents in the presence of supercritical fluid media have been reviewed by King (3), who has commented on the lack of fundamental knowledge on adsorbate(sorbate)/adsorbent(sorbent)/supercritical fluid systems. Indeed, with the exception of the sorbent regeneration studies performed at Critical Fluid Systems in the last... 

The research effort pursued several objectives (1) studies of the lignite pyrolysis, (2) research on catalyst improvement for cracking and upgrading of the volatile tars (sulfur, oxygen and nitrogen removal), (3) catalyst regeneration studies including how to handle the substantial heat developed. 

An informative example is naphtha reforming, in which the influence of regeneration also becomes apparent. The data in Table 5-43 suggest that regeneration of the catalyst by combustion of the coke leads to an increase in crystallite size, since the catalyst activity, measured by H2 adsorption, decreases steadily with time, in spite of regeneration. Studies of the reforming process with model substances found major changes in... 

Other studies looked into the use of composite microspheres of PLGA/HA in bone regeneration study results showed that the controlled release system of these microspheres functioned to improve osteoblast proliferation and also enabled upregulation of the key osteogenic enzyme alkaline phosphatase (ALP) [168]. 

Electrical stimulation has been shown to enhance nerve cell regeneration [124,125], the mechanisms for this effect are, however, unclear. One hypothesis is that an electrical stimulus alters the local electrical fields of extracellular matrix molecules, changing protein adsorption [126]. As early as 1994, studies into the suitability of ICPs such as PPy as neuronal scaffolds provided positive proof that these electroactive stimulus response polymers indeed have a role to play. Shastri et al. [127] showed that neurite extension of PC 12 cells was more pronounced on PPy surfaces as compared to tissue culture polystyrene. The authors also showed that the application of an electrical stimulus to the cell culture on the PPy film significantly increased the expression of neurites in the cells compared to the controls. In addition, they demonstrated through tissue compatibility and transected sciatic nerve regeneration studies in rat models that the PPy films invoke little negative response and support nerve regeneration. 

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