Paul J. Karol

Discovery of the elements with atomic numbers Z = 113, 115 and 117 (IUPAC Technical Report)

Abstract The fourth IUPAC/IUPAP Joint Working Party (JWP) on the priority of claims to the discovery of new elements 113, 115, 117 and 118 has reviewed the relevant literature pertaining to several claims. In accordance with the Criteria for the discovery of elements previously established by the 1991 IUPAC/IUPAP Transfermium Working Group (TWG), and reinforced in subsequent IUPAC/IUPAP JWP discussions, it was determined that the RIKEN collaboration has fulfilled those Criteria for element Z=113. The Dubna–Livermore–Oak Ridge collaborations claims for 115 and 117 are also in compliance. The discussion of element Z=118 will appear in a subsequent report. A synopsis of experiments and related efforts is presented along with some commentary guiding future applications of the Criteria.

Discovery of the elements with atomic numbers greater than or equal to 113 (IUPAC Technical Report)

The IUPAC/IUPAP Joint Working Party (JWP) on the priority of claims to the discovery of new elements 113–116 and 118 has reviewed the relevant literature pertaining to several claims. In accordance with the criteria for the discovery of elements previously established by the 1992 IUPAC/IUPAP Transfermium Working Group (TWG), and reinforced in subsequent IUPAC/IUPAP JWP discussions, it was determined that the Dubna-Livermore collaborations share in the fulfillment of those criteria both for elements Z = 114 and 116. A synopsis of experiments and related efforts is presented.

On the Claims for Discovery of Elements 110, 111, 112, 114, 116, and 118 (IUPAC Technical Report)

The IUPAC/IUPAP Joint Working Party on the priority of claims to the discovery of new elements has reviewed the relevant literature pertaining to several claims. In accordance with the criteria for the discovery of elements, previously established by the 1992 IUPAC/IUPAP Transfermium Working Group, and reinforced by the 1999 IUPAC/IUPAP Joint Working Party, it was determined that the claim by the Hofmann et al. research collaboration for the discovery of element 111 at Gesellschaft für Schwerionenforschung (GSI) has fulfilled those criteria. For elements 112, 114, and 116, the collaborations of Hofmann et al. and of Oganessian et al. produced high-quality data with plausible interpretations. However, confirmation by further results is needed to assign priority of discovery for these elements. The working party was not persuaded that other collaborations have satisfied the discovery criteria.

Discovery of the element with atomic number Z = 118 completing the 7th row of the periodic table (IUPAC Technical Report)

Abstract The fourth IUPAC/IUPAP Joint Working Party (JWP) on the priority of claims to the discovery of new elements 113, 115, 117 and 118 has reviewed the relevant literature pertaining to several claims. In accordance with the criteria for the discovery of elements previously established by the 1991 IUPAC/IUPAP Transfermium Working Group (TWG), and reinforced in subsequent IUPAC/IUPAP JWP discussions, it was determined that the Dubna-Livermore collaboration has fulfilled those criteria for element Z=118. A synopsis of experiments and related efforts is presented.

Discovery of the element with atomic number 112 (IUPAC Technical Report)

The IUPAC/IUPAP Joint Working Party (JWP) on the priority of claims to the discovery of new elements has reviewed the relevant literature pertaining to several claims. In accordance with the criteria for the discovery of elements previously established by the 1992 IUPAC/IUPAP Transfermium Working Group (TWG), and reiterated by the 1999 and 2003 IUPAC/IUPAP JWPs, it was determined that the 1996 and 2002 claims by the Hofmann et al. research collaborations for the discovery of the element with atomic number 112 at Gesellschaft für Schwerionenforschung (GSI) share in the fulfillment of those criteria. A synopsis of Z = 112 experiments and related efforts is presented. A subsequent report will address identification of higher-Z elements including those of odd atomic number.

On the discovery of the elements 110-112 (IUPAC Technical Report)

The IUPAC/IUPAP joint working party on the priority of claims to the discovery of elements 110, 111, and 112 has reviewed the relevant literature pertaining to the several claims. In accordance with the criteria for the discovery of elements, previously established by the 1992 IUPAC/IUPAP Transfermium Working Group, it was determined that the claim by the Hofmann et al. research collaboration for the discovery of element 110 at GSI has fulfilled those criteria. For elements 111 and 112, the collaboration of Hofmann et al. produced high-quality data with plausible interpretations, but confirmation by further results is needed to assign priority of discovery for these elements. The working party was not convinced that claims of other collaborations have satisfied the discovery criteria.

Rare earth separations using cation-exchange column chromatography : Comparison of -hydroxyisobutyric acid and -hydroxy methylbutyric acid as eluants

Abstract Separations of several adjacent rare earth pairs were investigated in order to compare the effectiveness of two eluting agents: α-hydroxyisobutyric acid (αHIBA) and α-hydroxy-α-methylbutyric acid (αHαMBA). The latter was found to be superior

Equilibrium elution chromatography : The column-origin boundary condition

Abstract Linear, equilibrium chromatography on a finite column has been re-examined using the rate model. Unlike most previous descriptions, the boundary condition at the column origin is treated as reflective. The development of the band profile on the column behaves in a physically and mathematically reasonable fashion. In this regard, long-standing disagreements on this fundamental issue are finally eliminated. For almost all practical situations, the use of Gaussian profiles for theoretical descriptions of on-column equilibrium chromatography appears valid.

The integral catcher analysis of nuclear recoil experiments

Abstract The integral thick target thick catcher equations for extracting excitation and relaxation recoil velocities of nuclear reaction products have been reformulated. The new data analysis scheme corrects certain limitations and deficiencies inherent in the conventional procedure. Like the latter, our integral catcher analysis uses forward and backward recoil fractions F and B , but has no constraints on target thickness. The utility of the method may be extended with advantage to thinner targets. Additionally, there are no restrictions on the form of the range-velocity relationship that can be employed. Finally, the procedure inherently provides an excellent evaluation of the statistical uncertainties in the derived velocities based on the experimental uncertainties in F and B .

Estimation of carbon‐11 in the atmosphere

The production of 20 minute C‐11 by interactions of cosmic ray primary and secondary particles with atmospheric nitrogen and oxygen is calculated. We estimate unmeasured C‐11 to be the fifth most active cosmogenic radionuclide in the lower atmosphere with a disintegration rate of 0.014 dpm/m3. Nevertheless, its actual measurement will not prove an easy task.