Gieseler

Gr. aktis, aktinos, beam or ray). Discovered by Andre Debierne in 1899 and independently by F. Giesel in 1902. Occurs naturally in association with uranium minerals. Actinium-227, a decay product of uranium-235, is a beta emitter with a 21.6-year half-life. Its principal decay products are thorium-227 (18.5-day half-life), radium-223 (11.4-day half-life), and a number of short-lived products including radon, bismuth, polonium, and lead isotopes. In equilibrium with its decay products, it is a powerful source of alpha rays. Actinium metal has been prepared by the reduction of actinium fluoride with lithium vapor at about 1100 to 1300-degrees G. The chemical behavior of actinium is similar to that of the rare earths, particularly lanthanum. Purified actinium comes into equilibrium with its decay products at the end of 185 days, and then decays according to its 21.6-year half-life. It is about 150 times as active as radium, making it of value in the production of neutrons. 

Plasticity can be studied using a device known as the Gieseler plastometer. A constant torque is appHed to a shaft with rabble arms imbedded in coal in a cmcible heated at a fixed rate. The rate of rotation of the shaft indicates the duidity of the coal and is plotted as a function of the coal temperature. These curves, as shown in Figure 8, have a well-defined peak for coking coals usually near 450°C. Softening occurs at 350—400°C. At a normal heating rate of 3°C/min, the duid hardening may be complete by 500°C. 

Fig. 8. Plasticity curve obtained using the Gieseler plastometer. Heating rate is 2°C/min.

A predictive macromolecular network decomposition model for coal conversion based on results of analytical measurements has been developed called the functional group, depolymerization, vaporization, cross-linking (EG-DVC) model (77). Data are obtained on weight loss on heating (thermogravimetry) and analysis of the evolved species by Eourier transform infrared spectrometry. Separate experimental data on solvent sweUing, solvent extraction, and Gieseler plastometry are also used in the model. 

Tropacocaine (Benzoyl-ili-tropeine), CuHj gOgN, was discovered by Giesel in Java coca leaves and has since been found in Peruvian coca. Its preparation from the former source has been described by Hara and Sakamoto, It crystallises in needles, m.p. 49°, is insoluble in water, but soluble in alcohol, ether or dilute ammonia and is generally prepared by benzoylating /t-tropine, and purified as the hydrochloride. Its alcoholic solution is alkaline and optically inactive. The hydrochloride forms needles, m.p. 271° (dec.), and the hydrobromide leaflets. The aurichloride separates in minute yellow needles, m.p. 208°, from hot aqueous solutions the picrate has m.p. 238-9°. When heated with hydrochloric acid or baryta water the alkaloid is hydrolysed to benzoic acid and -tropine. ... 

In 1899, the Curies first reported the coloration of glass and porcelain and the formation of ozone from oxygen by radioactive radiation. Giesel (1900) noted that the coloration of alkali halides under these radiations was similar to the effect of cathode rays he also observed the decomposition of water. R Curie and Debierne (1901) observed continuous evolution of hydrogen and oxygen... 

Gieseler et al. utilized tunable diode laser absorption spectroscopy to detect water vapor concentrations, gas velocities and mass flow during freeze-drying of pure water at different pressure and shelf temperature settings and of a 5%w/w mannitol solution. The analyzer was interfaced to the spool that connected the dryer chamber to the condenser. The reported method was advantageous in that primary and secondary drying end-point control based upon mass flow rate was independent of freeze-dryer size and configuration. ... 

H. Gieseler, W.J. Kessler, M. Finson, et al.. Evaluation of tunable diode laser absorption spectroscopy for in-process water vapor mass flux measurements during freeze drying, J. Pharm. Sci., 96(7), 1776-1793 (2007). 

Figure 6. Relations among fluorescence intensity, chloroform-solubles yield and Gieseler placticity for hydrogenated coal (PSOC-1510 solvent-free hydrogenation, 400 C 5-60 min 1% wt sulfided Mo 7 MPa H2 cold.

The high-volatile Liddell bituminous coal (Figure 2 (E)) shows little indication of thermally-activated molecular mobility below 500 K. There is some fusion between 500 and 600 K followed by a major fusion transition above 600 K which appears very similar to the high temperature transition of the Amberley coal. This Liddell coal, however, has only 6% liptinite, has a crucible swelling number of 6.5 and exhibits considerable Gieseler fluidity. We therefore attribute this high temperature fusion event to the aromatic-rich macerals of the coal and associate it with the thermoplastic phenomenon. This implies that a stage has been reached in the coalification processes at which aromatic-rich material becomes fusible. 

The element was discovered independently hy A. Dehierne and F. Giesel in 1899 and 1902, respectively. It is used in nuclear reactors as a source of neutrons. 

In 1899 AncLrt Debieme, a young chemist who had served as prepa-rateur under Charles Friedel and who was an intimate friend of the Curie family, discovered that another radioactive element is carried down with the precipitate of the rare earths produced by adding ammonium hydroxide to a solution obtained by dissolving pitchblende (40). This element, which he named actinium, was discovered independently in 1902 by F. Giesel, who removed it with the lanthanum and cerium (41) and called it emanium. 

The actinium series is very much like that of radium. In 1904 and 1905 Giesel and T. Godlewsld, while working independently, discovered the element actinium X, which is precipitated with the ferric hydroxide by adding an excess of ammonium carbonate solution to a solution containing actinium and iron (41, 44). 

Friedrich O. Giesel (bom 1852) was for many years a chemist at the quinine works of Braunschweig Buchler and Company, and in the early days he worked up large quantities of radioactive minerals and generously distributed his radium among investigators in all parts of the world (56). 

Oct. 8,1904 1904 1904-5 1905 Death of Winkler. Death of Demargay at Paris. Giesel and Godlewski independently discover actinium X. L. B. Mendel and H. C. Bradley discover zinc in the liver and respiratory protein of the snail Sycotypus. 

Fluidity data were determined by the Gieseler apparatus on the 16 size fractions of the medium volatile coal. The values obtained were relatively low, ranging from 8 to 81 dial divisions per minute. An attempt was made to correlate these results with petrographic data. Some of the possible relations examined are shown in Figure 4. A plot of the maceral vitrinite against fluidity shows considerable scatter as does a plot of the ash content vs. fluidity. The ash content was determined by proximate analysis (see Table I) and is included here for comparison. 

Figure 4. Relation of fluidity (Gieseler) to some petrographic parameters...

Presently. 24 isotopes of actinium, with mass numbers ranging from 207 to 2.30, have been identified. All are radioactive. One year after the discovery of polonium and radinm by the Curies, A. Debierne found an unidentified radioactive substance in the residue after treatment of pitchblende. Debierne named the new material actinium after the Greek word for ray. F. Giesel, independently in 1902, also found a radioactive material in the rare-earth extracts of pitchblende. He named... 

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