Sommer studies

A black coloration that appeared during the experiments at pH values >6.5 indicated the formation of FeS. However, the black disappeared again toward the end of the experiments. Apparently most of the sulfide stored in FeS was also oxidized, and only a small portion of the sulfide may have remained as FeS. This development is not surprising because we worked with excess ferric oxide, in contrast to Pyzik and Sommers study (21) in which FeS could accumulate during the experiments. We concluded that the ferrous iron released after redissolution of FeS adsorbs to the ferric oxide surface and forms a surface complex >FeO-Fe+ (reaction 7), to which poly sulfides may bond. 

Technique. Acidity. The number of acid sites was determined by titration with n-butylamine. Hammett and arylmethanol indicators chosen according to Drushel and Sommers studies (4) were used to obtain the catalyst acidity in terms of acid strength (7). Numerical results obtained by this method are similar to those obtained by other methods, for example, adsorption (i, 14,15). 

Ivanov, D.A. and Magonov, S.N., Atomic Force Microscopy Studies of Semicrystalline Polymers at Variable Temperature, in Polymer Crystallization Observations, Concepts and Interpretations, Sommer, J.-U. and Reiter, G., Eds., Springer, Heidelberg, Germany, 2003, chap. 7. 

Chen S, Truax LA, Sommers JM (2000) Alkanethiolate-protected PbS nanoclusters Synthesis, spectroscopic and electrochemical studies. Chem Mater 12 3864-3870... 

He, G. L., Merlitz, H., Sommer, J. U. and Wu, C. X. (2007) Static and dynamic properties of polymer brushes at moderate and high grafting densities A molecular dynamics study. Macromolecules, 40, 6721-6730. 

D.A. Ivanov and S. Magonov, Atomic force microscopy studies of semicrystalline polymers at variable temperature. In G. Reiter, J.-V. Sommer (Eds.), Polymer Crystallization, Springer, Berlin, 2003, p. 98. 

Sommer showed in an elegant study with optically active a-naphthyl-phenylmethylsilane, R3Si H (28), that an exchange of this kind can be faster than hydrosilation. 

By using a thermodynamic model based on the formation of self-associates, as proposed by Singh and Sommer (1992), Akinlade and Awe (2006) studied the composition dependence of the bulk and surface properties of some liquid alloys (Tl-Ga at 700°C, Cd-Zn at 627°C). Positive deviations of the mixing properties from ideal solution behaviour were explained and the degree of phase separation was computed both for bulk alloys and for the surface. 

Pharmaceutical Comparison. At least 8 studies to date have examined the effectiveness of hypericum compared to the pharmaceutical antidepressants imipramine, amitriptyline, and maprotiline. Preliminary results indicate that hypericum is equivalent to standard antidepressants in effectiveness (Linde et al. 1996 Vorbach 1997). Similar to the pharmaceutical antidepressants, there is a 10-14 day lag for therapeutic effects of hypericum (Harrer et al. 1994). Indeed, the differences seen between hypericum and placebo groups becomes apparent between 2 and 4 weeks (Sommer and Harrer 1994). Hypericum has been reported to have a more favorable side-effect profile than several pharmaceutical antidepressants as well (Vorbach et al. 1994 Harrer et al. 1994). In double-blind studies, subjects have reported fewer and less-severe side effects. Although these initial results are promising, Linde and colleagues (1996) have concluded that the present evidence is inadequate to establish... 

Sommer H, Harrer G. (1994). Placebo-controlled double-blind study examining the effectiveness of an hypericum preparation in 105 mildly depressed patients. J Geriatr Psychiatry Neurol. 7(suppl 1) S9-11. 

Kreuter A, Sommer A, Hyun J, Brautigam M, Brockmeyer NH, Altmeyer P, Gambichler T. (2006) 1% pimecrolimus, 0.005% calcipotriol, and 0.1% betamethasone in the treatment of intertriginous psoriasis A double-blind, randomized controlled study. Arch Dermatol 142 1138-1143. 

Sommer, B.A. Margerum, D.W. (1970) Kinetic study of the hydroxoiron(III) dimer. Inorg. Chem. 9 2517-2521... 

The generation of silyl radicals, species which have proven to be of great value in both mechanistic and synthetic studies, was reported independently in 1947 by Sommer and Whitmore (equation 63), " and by Barry et al. at Dovvf Chemical. " These are useful for many purposes, including halide reductions. " ... 

Gee, R, Sommers, C.H., Melick, A.S., Gidrol, X.M., Todd, M.D., Burris, R.B., Nelson, M.E., Klemm, R.C. Zeiger, E. (1998) Comparison of responses of base-specific Salmonella tester strains with the traditional strains for identifying mutagens the results of avahdation study. Mutat. Res., 412, 115-130... 

Reetz and Sommer then studied the intramolecular hydroarylation of alkynes when they were looking for carbon triple bond coupling reactions. Depending on the substrate, the choice of gold(I) or gold(III) species was crucial [127]. 

Basic investigations in mass spectrometry39,40 continue to influence instrumental developments. The first application in ion cyclotron resonance mass spectrometry (ICR-MS) was described by Sommer, Thomas and Hippie in 1949.41 Free radicals were also mass spectrometrically studied by... 

The effects of heat treatment of milk on the oxidation-reduction potential have been studied to a considerable extent (Eilers et al 1947 Gould and Sommer 1939 Harland et al 1952 Josephson and Doan 1939). A sharp decrease in the potential coincides with the liberation of sulfhydryl groups by denaturation of the protein, primarily /3-lactoglobulin. Minimum potentials are attainable by deaeration and high-temperature-short-time heat treatments (Higginbottom and Taylor 1960). Such treatments also produce dried milks of superior stability against oxidative flavor deterioration (Harland et al 1952). 

Research reports on milk stability have been published frequently since about 1919. Early studies were prompted by the need to ensure sufficient heat stability for evaporated milk to withstand heat sterilization (Sommer and Hart 1919, 1922). Between 1919 and 1960, most attention was directed to the influence of milk salts on heat stability (Miller and Sommer 1940 Pyne 1958 Pyne and McHenry 1955). It was not until the early 1960s that the importance of heating time and pH on coagulation of milk was appreciated (Rose 1961A.B). More recent work has been concerned with factors which affect the stability of milk proteins. 

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