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Iron-chromium-phosphorus (Fe–Cr–P) alloys were prepared by electrodeposition from an acidic citrate electrolyte using sodium hypophosphite as the source of phosphorus. These alloys form a passive oxide layer when exposed to air and are useful as protective coatings on steel. The current efficiency of the plating process reaches a maximum of 20% at a current density of 100 mA/cm2 where the alloy has 10% Cr and 19% P. X-ray diffraction patterns and TEM analysis show that the alloy is amorphous. TEM results also indicate that small oxide particles (5–20 nm) are dispersed in the amorphous structure. Besides Fe, Cr, and P, the alloys contain a low level of oxygen (4–7%) in the form of mixed iron and chromium oxides, as confirmed by AES analysis. When heated, the amorphous structure transforms into a mixture of Fe3P and Cr3P, along with α–Fe–Cr grains. This phase transformation occurs in the temperature range of 450–460 °C for alloys with 19% P.

Sintered nickel positive electrodes were prepared by electroimpregnating nickel hydroxide inside a porous nickel plaque in a nickel nitrate solution. The distribution of nickel hydroxide inside the plaque was measured using a radio-tracer method with /sup 63/Ni as the radioactivity source. Autoradiography and ..beta.. counting were used to follow qualitative and quantitative distributions, respectively, of the pore filling process. Relatively uniform distribution was observed at low current density, and the precipitation of Ni(OH)/sub 2/ extends to the center of the plaque. At high current density, most of the Ni(OH)/sub 2/ aggregated in the region just underneath the plaque surface, causing a somewhat nonuniform distribution. Nickel hydroxide also precipitates heavily on the surface of the plaque at high current density, reducing the penetration of electrolyte to the inside of the plaque.

The prominent role of plasma fibronectin (pFN) in the host defense system as an opsonin for gelatin (collagen)-coated colloids has been established. In the present study we investigated the interaction of pFN and membrane isolates from cells devoid of collagen, as well as several tissues. In a liver slice assay system it was shown that subcellular membrane fractions from lung macrophages, peritoneal exudate cells, spleen, testes, and liver were able to competitively inhibit the pFN-mediated uptake of 125l-gelatin coated latex beads (gLtx*) at low concentrations. Endocytosis of 125l-labeled membrane isolates by macrophage monolayers was also promoted by addition of pFN. In an attempt to characterize the membrane component(s) interacting with pFN, it was found that mild extraction procedure with 1 M KBr could release a significant amount of this inhibitory activity. Further studies demonstrated that the agent(s) responsible for inhibition of gLtx* uptake was heat sensitive, not altered by trypsin treatment, and did not contain actin, a protein known to interact with pFN. This work indicates that pFN interacts specifically with an as yet unknown membrane component(s) and that such interaction will promote clearance of cellular debris by macrophages. This suggests that pFN may be an important opsonin for the reticuloendothelial system in clearance of collagenous and noncollagenous cellular debris once they are exposed to interact with it.

An analysis is presented for describing behavior of a packed‐bed electrode confined within a thin cylindrical porous separator and surrounded by a concentric counterelectrode. Electrolytic solution, containing reactive species, flows axially in plug flow through the packed‐bed electrode while the peripheral surface of the packed bed is held under a constant applied potential. Results are obtained for two types of porous separators, (i) permeable to all solute species and (ii) impermeable to the reactive solute species. For each case, the two‐dimensional (radial and axial) concentration, potential, and current distributions are calculated by a finite difference method. The results clarify over‐all reactor performance and, in particular, predict the relation between the volumetric reaction rate and the residence time for a wide range of system parameters.

The technique of integrating Donnan dialysis with electrolysis was evaluated for regenerating a chromic acid solution contaminated with copper. Electrolysis converts the reduced chromium (Cr 3+ ) to the active form (Cr 6+ , as dichromate), but cannot remove copper efficiently. A dialyzer in series greatly increases the copper removal efficiency by providing a facile route for copper ions to reach the catholyte where they are electrodeposited.

Contact shift and line broadening studies were made on a series of metal ion-dimethylsulfoxide (DMSO) solutions. Unpaired spin density transfer for Cu(DMSO)62+ and Ni (DMSO)62+ complexes is through the σ bonding system while the signs of the electron spin-nuclear spin coupling constants, An, for Co(DMSO)62+, Fe(DMSO)62+ indicate a ligand π-to-metal t2g unpaired spin density transfer. Line broadening studies reveal that Co(DMSO)62+ and Mn(DMSO)62+ exchange too fast in DMSO solution to be measured by the NMR technique while Fe(DMSO)63+ and Cr(DMSO)63+ exchange too slowly to be measured. The exchange rate and the ΔH‡ and ΔS‡ of exchange were determined for Cu(DMSO)62+, Ni(DMSO)62+ and Fe(DMSO)62+. The exchange rate order was found to be Fe > Cu > Ni.

La vitesse de transfert des ions a travers une membrane selective de cations depend des proprietes de la membrane, de la concentration de la solution et de l'environnement hydrodynamique a l'exterieur de la membrane. On etudie ici, l'influence de la concentration et de la vitesse d'ecoulement de la solution sur le transfert des ions a travers une membrane tubulaire d'acide perfluorosulfonique. Les essais sont realises avec une solution de sulfate de Cu

Thin film nickel‐phosphorus alloys are electrodeposited at a high rate using a specialized rapid electrolyte flow system. Current densities up to 2.33 A/cm2, which are difficult to maintain in conventional plating processes, can be used to produce satisfactory films. The deposits are characterized by x‐ray diffraction and differential scanning calorimetry. Phosphorus content decreases with increasing current density and is virtually independent of the electrolyte flow rate above 5.7 m/s, where the system is operating in the turbulent regime. Deposit structure depends strongly on the phosphorus content; it is amorphous or highly microcrystalline at >14 atom percent (a/o) and crystalline at