Group displacement laws

Group Displacement Law The emission of a-rays by an element results in the formation of new element which lies two places left to the parent element and the emission of a b-particle results in the formation of a new element which lies one place right to the parent element in the periodic table. 

Uranium Y is isotopic with uranium X, and is therefore tetravalent. Since it gi es off -rays, it is unlikely, according to the Group-displacement Law, that it will change directly into trivalent actinium there should be an intermediate a-ray product. This conclusion was cozi-firmed by the discovery of eka-tantalum or protoactiniuni, which is the immediate parent of actinium. ... 

The positions of these elements in the Periodic Table, according to the Group-displacement Law, is shown in the following table ... 

At Glasgow, Soddy posited his group displacement law, which stated that the emission of an a-particle (a doubly charged particle consisting of two protons and two neutrons, identical to the hefium nucleus, He ) from a radioactive element causes that element to move back two places in the... 

Kauffman, George B. (1982). The Atomic Weight of Lead of Radioactive Origin A Confirmation of the Concept of Isotopy and the Group Displacement Laws. ... 

U/Ac ratio was found to be constant, but the amount of actinium present was nevertheless less than would be expected if it were a direct disintegration product of uranium. This was the reason for assuming it to lie in a separate chain. By the Group Displacement Law protactinium should belong to Group v and thus resemble tantalum. It was this consideration that led to its discovery. 

One end of each surface-active molecule in a monolayer is anchored firmly to the Uquid surface by the attraction of the polar head group for the aqueous subphase, while the hydrophobic portion is displaced easily from it. If the molecules are separated widely as in a gaseous monolayer, the simple two-dimensional gas law is approached, namely, irA = kT, where k is the Boltzmann constant. The hydro-phobic chains are free to assume almost any orientation above the surface and may sweep out circles with radii as long as their tails by rotating around their point of attachment at the head group. However, intermolecular translational movements are restricted to the two-dimensional interfacial plane because the hydrophilic head groups cannot leave the aqueous surface. 

On the other hand, the group of Briels [54] recently proposed a coarse graining in terms of blobs with coarse grained properties determined beforehand by atomistic simulations. The mean-square displacement of these blobs displays only a very narrow Rouse regime and then is slowed down further, but never reaches the power law of reptation. The authors relate this observation to the shortness of the chains ( 8 entanglement lengths) and their averaging over all blobs (not only the innermost ). 

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