The Controversial Element

Notice that Moseley had made a minor mistake in the atomic number determinations of both holmium and dysprosium. The atomic number of holmium is namely 67, and dysprosium has an atomic number of 66. It also appears that Moseley attached some credence to the investigation of Auer von Welsbach who had demonstrated the complexity of thulium in 1911 by splitting it into three components. Moseley had incorporated two of these components (Tml and Tmll) in his atomic number sequence. Moseley therefore ascribed Urbain s neo-ytterbium and lutetium too high an atomic number (in reality the atomic numbers of ytterbium and 

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As Table 21-1 suggests, molecular chlorine is a tremendously versatile industrial chemical. This element is a leading industrial chemical because of this versatility rather than any single application, although polymers account for about one third of its uses. In recent years, however, the industrial use of chlorine has come under strong attack from many environmentally conscious groups. One major reason is that dioxins, one class of by-products of chlorine reactions, have a very detrimental effect on biosystems. The controversy over industrial chlorine is described in our Chemistry and the Environment Box on page 936. 

However, it must be emphasized that interpretation of elemental diffusion in feldspars is complicated by the structural state of the polymorphs, which vary in a complex fashion with temperature, chemistry and re-equilibration kinetics. These complexities also account for the controversies existing in the literature regarding diffusion energy in these phases (see also, incidentally, figure 4.8). Elemental dilfusivity data for rock-forming silicates are listed in table 4.8. 

Lithium, beryllium, boron and the controversy over oxygen and the origin of the light elements... 

Some controversy surrounds the usage of the term in situ. Some researchers even go so far as to suggest that unless a reactor and spectroscopic cell/probe are one and the same unit, the measurement cannot be in situ. The results of Section 4.3.1 suggest otherwise. If the fluid elements in the cell are compositionally similar to the fluid elements in the CSTR and are at similar temperature and pressure, then they are indistinguishable. The measurements are in situ. With proper care regarding transport effects, and reaction considerations, an experimental apparatus with a configuration like Figure 4.1 provides in situ spectroscopic capability for dark reactions. 

Both sides of the controversy regarding the name of element 72 are presented in the English journals, Nature and Chemistry and Industry (16, 24). 

The controversy was not really about science. The use of law and coercion to defend a theory was not so much an indication that the authorities cared deeply about the nature of the elements as a reflection of their wish to preserve the status quo. Like Galileo s trial before the Inquisition, this was not an argument about truth but a struggle for power, a sign of the religious dogmatism of the Counter-Reformation. 

Unfortunately it is difficult to resolve the X-ray diffraction of the carbon atoms in these compounds from that of the heavy elements present, and in no case are the metal-carbon or carbon-carbon distances known with sufficient accuracy to enable pronouncements about the carbon-carbon bond order to be made. In this respect the infrared spectra ought to be helpful, but there is considerable controversy over the assignment of absorption... 

The trace element threat must be defined in quantitative as well as qualitative terms. It is no easy matter when one considers the number of years it took to establish the relationship between cigarette smoking and lung cancer, where statisticians had the luxury of a control group and groups of graded exposures with which to establish a dose-response relationship. The identity of the carcinogen (s) is still a subject of controversy. 

S100A1 is the most abundant S100 protein found in striated muscle and predominates in myocardial tissue (Kato and Kimura, 1985). Besides its cytoplasmic occurrence, S100A1 was reported in these cells to associate with the sarcolemma, sarcoplasmatic reticulum (SR), contractile filaments, intercalated discs, outer mitochondrial membrane and other intracellular membrane stmctures (Arcuri et al., 2002 Donato et al., 1989 Haimoto and Kato, 1988 Sorci et al., 1999). However, the exact location of S100A1 on the contractile elements of the sarcomere is still controversial (Maco et al., 2001 Zimmer, 1991). 

On several occasions, letters were sent to the couple asking whether the discovery had received confirmation or not. [51] Walter Noddack just kept silent, and even more and more silent as the years went by. The Noddacks felt they were unable to provide any kind of proof. Not only were they unable to show a sample of masurium which would have, as had been the case for rhenium, closed the controversy on the existence of the element, but even the original photographic plate of typical spectral lines was never shown as a piece of evidence. [52]... 

Hevesy s close friend and collaborator, the distinguished Austrian (and later British) chemist Friedrich Paneth, was yet another radiochemist who turned to geo-and cosmochemistry in the 1920s. He started a research program on meteoritic chemistry that made him an authority in the field of meteorite science and one of the founders of modern cosmochemistry. [59] It is also worth to mention that Hevesy s old rival from the controversy over element 72, the Frenchman Alexandre Dauvillier, turned from X-ray spectroscopy to astro- and cosmochemistry. In 1955 he wrote one of the first books ever on cosmochemistry. [60]... 

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