Experimental hints

The application of in situ surface analysis has given some experimental hints [155, 175-177, 244, 249] on the operation of material dynamics in working VPO... 

The first experimental hint for a finite lifetime of an alkyl halide anion radical in homogeneous etheral solution was provided by Garst and coworkers in 1977. From the reduction of 5-hexenyl chloride, bromide and iodide with disodium tetraphenylethylene in 2-methyltetrahydrofuran (MTHF) at 20°C they concluded that radical anions R-X Na were involved and that the order of their stability was R-I Na" >R-Br Na > R-CrNa. ... 

Summary Reactions of dichlorodivinylsilane and LitBu in a molar ratio 1 1 and 1 2 lead to highly reactive intermediates, which can be trapped by suitable trapping agents. From that mono and double addition products are formed, which provide experimental hints for the intermediate formation of the neopentylsilene H2C=CH(Cl)Si=CHCH2/Bu 3 and the 2-silaallene tBuCH2CH=Si=CHCH2tBu 4. In particular, the formation of double cycloadducts from 2 with Lifflu is a preparatively facile route for the synthesis of silaspirocycles such as 12, 14, and 15, which could be characterized by single crystal X-ray structure analysis. 

Some experimental hints, however, give more information. Thus, finely divided palladium metal is readily oxidized under the reaction conditions by oxygen in the presence of acetic acid, even in the absence of any additional oxidant (eq. (15)) [27, 39],... 

There exist some experimental hints for such a limit but a clear experimental proof is missing. 

Animal Models Early experimental hints for protein immunogenicity may arise from animal models, especially from experiments with transgenic animals that are tolerant to the human protein [65], hut might develop anti-protein variant anti-hodies. On the other hand, if the drug fails to stimulate an immune response in normal (nonengineered) animals, preferably in non-human primates, even when administered with some adjuvant, then there is a good probability of low immunogenicity in humans [66, 67]. 

There are theories and experimental hints suggesting that another domain of stability could possibly be reached at higher values of beta (see B. Coppi s lecture). 

It should be stressed again that the change of the exponent a constitutes the only vague experimental hint for the existence of an overlap concentration in solutions of intrinsically flexible polyions at low ionic strength... 

Rie] Ried, K., Kohler, D., Kronmuller, H., Experimental Hints for Crossover-Behavior in the Ferromagnetic Phase-Transition of Fei4Nd2B , J. Magn. Magn. Mater., 116, 259-266 (1992) (Phase relations. Experimental, Magn. Prop., 33)... 

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