Surface states of metastable (GaAs)1−xGe2x alloys

The proposed order-disorder transition as x varies in metastable (GaAs)_1?xGe_2x alloys should be observable in photoemission experiments. There should be large “kinks” in the (100) surface state energies as functions of x near the critical composition x_c.     

Cell surface receptors for endogenous mouse type C viral glycoproteins and epidermal growth factor: tissue distribution in vivo and possible participation in specific cell-cell interaction

We have described previously the detection and tissue distribution of free cell surface receptors for ecotropic R-MuLV envelope glycoprotein and the growth factor EGF in vivo [1]. More recently, we have reported the chromosomal map position of the ecotropic viral receptor and its conservation between subspecies of the genus Mus [2]. This work has shown, for the first time, the presence of multiple, independently segregating cell surface receptor genes specific for different classes of ecotropic type C viral envelope glycoprotein. In this report we extend these findings and identify chromosome 2 as coding for the receptor used by M813, an ecotropic MuLV from a feral Asian mouse. This new receptor is probably also used by oncogenic, recombinant (MCF class) MuLV of C3H origin.     

Stoichiometry and morphology in terbium nitrate-poly(ethylene oxide) macromolecular complex

The Tb (NO₃)₃-PEO system was characterized to have a solubility limit equivalent to n ? 6.5 and a coordination number of 12.4 ± 0.1, compared to 5.0 and 10.9 ± 0.1 for the Nd(NO₃)₃-PEO system. The greater coordination involving Tb³⁺ appears to be responsible for the lower asymptotic glass transition temperature at high doping levels of the Tb(NO₃)₃-PEO complex. In both systems, anhydrous amorphous complexes were obtained below the respective solubility limits, over which apparent solubilities were found to be enhanced by the presence of tightly bound moisture while retaining the amorphous character of the complexes. Whereas partial precipitation was observed in the Tb(NO₃)₃-PEO system upon exposure to ambient moisture, both complexation and amorphous character were found to persist in the Nd(NO₃)₃-PEO system in the presence of absorbed moisture. © 1994 John Wiley & Sons, Inc.     

Underwater life support based on immobilized oxygen carriers

One of the primary problems that hinders humans in their efforts to explore and develop the ocean realms is the lack of a ready supply of oxygen. Practical methods have not yet been devised for using the vast amount of oxygen dissolved in ocean waters for human life support in an undersea environment. Fish and other water-breathing animals have solved this problem by utilizing hemoglobin as a molecular oxygen pump. To achieve a similar oxygen extraction capability, we have explored various methods of oxygen extraction that are based on immobilized forms of hemoglobin. Improved methods for immobilizing hemoglobin or other oxygen carrying molecules and a method for extracting the available dissolved oxygen from natural waters and other fluids are described. The techniques that have been developed allow for immobilization of oxygen carriers at high concentration in a state where they are capable of reversible oxygen binding, and also allow for regeneration of the carrier in the event of oxidation of the oxygen-binding site.     

Electron localization for a model of layered metallic structures

Several exact results are presented for a one-dimensional tight-binding model of layered binary metallic structures for the cases of arbitrary, random, incommensurate, and commensurate layer sequences.