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Abstract  

The infinite dilution activity coefficients of alkane (hexane, octane, decane and dodecane) in alkane (hexadecane and octadecane) were measured in the region of 313–470 K using a gas stripping method. The experimental results were predicted by the modified ASOG previously proposed.

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Abstract  

The infinite dilution resonance integrals of fifteen (n,γ)reactions leading to the production of short-lived radioisotopes were determined. The irradiation parameters were checked by comparing the results of different methods and the measuring equipment was carefully controlled.

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Abstract  

In this paper a possible relation between the effective resonance energy and the infinite dilution resonance integral of (n,) reactions is discussed. These two parameters are important data in thermal neutron activation analysis when using the single comparator method based on the Høgdahl convention. The values for these two parameters of more than one hundred (n,) reactions are considered, and the possibility of a — 2/3 power function is proposed.

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Abstract  

The resonance integrals for 59 isotopes were determined by neutron activation in reactor Thetis. The irradiations were carried out with and without Cd cover. The ratios of the thermal to epithermal fluxes were calculated from the Cd ratio of a Au monitor. From the induced activities in 36 elements, measured by means of γ-spectrometry with Ge(Li) and NaI(Tl) detectors, the values of I0th were obtained.

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Abstract  

In this second part the list of resonance integrals is completed with 63 values for (n, γ) reactions mainly from the second part of the periodic system. The resonance integral for (n, fission) of235U is included as well as thermal and epithermal self-shielding curves for the elements Sm, Eu, Gd, Dy and Cd.

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Abstract  

The enthalpies of dilution of aqueous solutions of methanol, ethanol, l-propanol, 2-propanol, 1-butanol, l-pentanol, 1-hexanol, cyclohexanol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol and poly-alcohol(cyclohexaamylose) have been determined at high dilution as a function of the mole fraction of alcohol at 298.15 K, by a rocking twin-microcalorimeter of the heat-conduction type. A smoothing equation of the enthalpies of dilution against the mole fractions of alcohols are given. The graphical comparison of experimental results with their smoothed values or literature ones, taking into account the dependence of the mole fractions, are also presented. It has been found for the aqueous solutions of shorter n-alcohols than hexanol that at very high dilution, exothermic values of molar enthalpies of dilution from a definite mole fraction of alcohols to infinite dilution with the change of mole fraction is proportional to carbon number of n-alcohols. The molar enthalpies of infinite dilution of aqueous butanediol isomers and 1-hexanol were very large. Molar enthalpies of infinite dilution of aqueous poly-alcohol (cyclohexaamylose) were endothermic.

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Abstract  

The heat capacities of binary aqueous solutions of 1,2-ethanediol, 1,2-propanediol and 1,2-butanediol were measured at temperatures ranging from 283.15 to 338.15 K by differential scanning calorimetry. The partial molar heat capacities at the infinite dilution were then calculated for the respective alkanediols. For 1,2-ethanediol or 1,2-propanediol, the partial molar heat capacities at the infinite dilution of increased with increasing temperature. In contrast, the partial molar heat capacities of 1,2-butanediol at the infinite dilution decreased with increasing temperature. Heat capacity changes by dissolution of the alkanediols were also determined. Heat capacity changes caused by the dissolution of 1,2-ethanediol or 1,2-propanediol were increase with increasing temperature. On the other hand, heat capacity changes caused by the dissolution of 1,2-butanediol are decrease with increasing temperature. Thus our results indicated that the structural changes of water caused by the dissolution of 1,2-butanediol differed from that of the two other alkanediols.

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water at: filled diamonds , 278.15 K; filled squares , 288.15 K; filled triangles , 298.15 K; and times , 308.15 K The molal enthalpies at infinite dilution, , were calculated by weighted least squares regression

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) and the co-solvent alkanol (2) 11 and 12 We are interested to focus on the partial molar volumes of cyclopentane at infinite dilution ( x 1 = 0) in alkanol and the partial molar volume of alkanol at infinite dilution ( x 2 = 0) in cyclopentane

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compressibility, K s,ϕ with molar concentration can be adequately represented by the Masson’s equation. 4 where Y represents V ϕ and K s,ϕ , Y 0 is the value at infinite dilution and S v and S k experimental slope, m is the molality. The limiting

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