Characteristic examples of three types of change of form of p n relationships at 2 5 T , as the contents of elements alloying with palladium a r e gradually increased (4,37,70,74-83,95-98,~04,108,153,154), are illustrated in Figure 9. As for the palladiumhydrogen system itself (4), such relationships have been determined from direct equilibrations with hydrogen gas, as well as being derived from measurements of electrode potential. Similarly as for palladium-hydrogen, temperature dependences of the p n relationships have been used to supplement calorimetric data ( I 10) in deriving heats and cntropies of hydrogen absorption, both at initially low values (79)(80)(81)(82)95,100,108) of hydrogen content (n-to) and over (Y =p transition regionsThe sequence of relationships in Figure 9(c) (4,37,70,74-83,'04,I54,I78).shows gradual increases with increasing rhodium content in the range o f n over which (Y and / J ' phases coexist. This sequence now seems unique to the palladium-rhodium-hydrogen system (45,75, I 53,154), since some suggestions of similarities of the palladium-manganesehydrogen system (179) seem doubtful in view of possible incomplete equilibrations.'The remaining families of p n isotherms for palladium alloy-hydrogen systems would thus seem to be divisible into two groups represented by those in Figures 9(a) and 9 (b). In both cases the ranges of n over t i + p phase regions are successively shortened with increasing content of the alloying element, even in the cases of alloys with readily hydride-forming transition or inner transition elements such as vanadium Decreases, in the range of n over (r +/I regions, with increasing amounts of alloying elements, have continued to be deduced from X-ray determinations of and / 3 phase lattice constants for additional palladium alloyhydrogen systems (4,79-82,157, I 80-1 82).Apart from the probable case of the palladium-nickel-hydrogen system (so), these general trends of decreasing extents of ( Y , p coexistence with increasing contents of alloying element are similar to the effects of increasing temperature in the palladium-hydrogen system, being accompanied by decreases in the extents of hystereses of absorption and desorption relationships between hydrogen contents and other experimental parameters (4,69,(96)(97)(98) later, has importance in choices of alloy compositions as hydrogen permeation membranes. In addition to the arguments concerning the solubility of hydrogen in the palladium-silver alloys, the extents of decreases of hydrogen solubilities with increasing contents of other alloying metals have been used (95,104,108) in support of an essentially protonic nature of the hydrogen entities. However, in order to allow for proposed levels of electron donation it has seemed necessary to postulate adoptions of oxidation states by the alloying elements which can be difficult to reconcile with their relative positions in sequence of electronegaiivities.Moreover as for the palladium-hydrogen system, latterly there has been increasing emphasis on the account ...

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We are right to see power, prestige, and confidence as conditioned by the Civil War. But it is a very easy step to regard the War, therefore, as a jolly piece of luck only slightly disguised, part of our divinely instituted success story, and to think, in some shadowy corner of the mind, of the dead at Gettysburg as a small price to pay for the development of a really satisfactory and cheap compact car with decent pick-up and road-holding capability. It is to our credit that we survived the War and tempered our national fiber in the process, but human decency and the future security of our country demand that we look at the costs. We hope that this article will help to resolve some of the broader issues concerning the economic effects of the war. Although this work does not answer completely the questions raised by the classic studies in this field, it does provide data which should be helpful in unriddling some of them.The

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The course of absorption of hydrogen by palladium has been studied in aqueous solutions using cold drawn and annealed wire specimens. The final volume of hydrogen absorbed from solution is found to be equal to the equilibrium concentration reported for direct absorption from the gas phase. Factors influencing the approach to equilibrium have been investigated. The progress of absorption of hydrogen was followed by measurement of changes in the relative resistance of the specimens. The relation between hydrogen content and relative resistance was reinvestigated for the palladium used in this work. Under the conditions employed, processes at the palladium surface are the determining factors in the absorption of hydrogen.

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