Estimating the Minimum Number of Individuals (MNI) For Skeletal Collections With Consideration to the Introduction of Procurement Bias

Of the competing methods for the estimation of the number of individuals represented within a skeletal assemblage, variations of the calculation of MNI (Minimum Number of Individuals) are most often employed. This presentation provides the preliminary results of an exhaustive study designed to determine the minimum number of individuals represented within a collection of 1,065 skeletal elements and fragments, belonging to the Eastern Washington University Anthropology Program. Results produced by established methods of computation were reinterpreted to account for the introduction of Procurement Bias in the calculation of MNI

New Stellar (n,γ)(n,\gamma) Cross Sections and The "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars"

Since April 2005 a regularly updated stellar neutron cross section compilation is available online at http://nuclear-astrophysics.fzk.de/kadonis. This online-database is called the "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars" project and is based on the previous Bao et al. compilation from the year 2000. The present version \textsc{KADoNiS} v0.2 (January 2007) includes recommended cross sections for 280 isotopes between $^{1}$H and $^{210}$Po and 75 semi-empirical estimates for isotopes without experimental information. Concerning stellar $(n,\gamma)$ cross sections of the 32 stable, proton-rich isotopes produced by the $p$ process experimental information is only available for 20 isotopes, but 9 of them have rather large uncertainties of $\geq$9%. The first part of a systematic study of stellar $(n,\gamma)$ cross sections of the $p$-process isotopes $^{74}$Se, $^{84}$Sr, $^{102}$Pd, $^{120}$Te, $^{130}$Ba, $^{132}$Ba, $^{156}$Dy, and $^{174}$Hf is presented. In another application \textsc{KADoNiS} v0.2 was used for an modification of a reaction library of Basel university. With this modified library $p$-process network calculations were carried out and compared to previous results.Comment: Proceedings "International Conference on Nuclear Data for Science and Technology 2007", Nice/ Franc

Stellar (n,gamma) cross sections of p-process isotopes PartI: 102Pd, 120Te, 130,132Ba,and 156Dy

We have investigated the (n,gamma) cross sections of p-process isotopes with the activation technique. The measurements were carried out at the Karlsruhe Van de Graaff accelerator using the 7Li(p,n)7Be source for simulating a Maxwellian neutron distribution of kT = 25 keV. Stellar cross section measurements are reported for the light p-process isotopes 102Pd, 120Te, 130,132Ba, and 156Dy. In a following paper the cross sections of 168Yb, 180W, 184Os, 190Pt, and 196Hg will be discussed. The data are extrapolated to p-process energies by including information from evaluated nuclear data libraries. The results are compared to standard Hauser-Feshbach models frequently used in astrophysics.Comment: 13 pages, 4 figure

V2:Performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz

The performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz with a maximum peak energy of 10 MJ is described. The solid deuterium converter with a volume of V=160 cm3 (8 mol), which is exposed to a thermal neutron fluence of 4.5x10^13 n/cm2, delivers up to 550 000 UCN per pulse outside of the biological shield at the experimental area. UCN densities of ~ 10/cm3 are obtained in stainless steel bottles of V ~ 10 L resulting in a storage efficiency of ~20%. The measured UCN yields compare well with the predictions from a Monte Carlo simulation developed to model the source and to optimize its performance for the upcoming upgrade of the TRIGA Mainz into a user facility for UCN physics.Comment: 23 pages, 8 figure

pp-Process simulations with a modified reaction library

We have performed $p$-process simulations with the most recent stellar $(n,\gamma)$ cross sections from the "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars" project (version v0.2, http://nuclear-astrophysics.fzk.de/kadonis). The simulations were carried out with a parametrized supernova type II shock front model (``$\gamma$ process'') of a 25 solar mass star and compared to recently published results. A decrease in the normalized overproduction factor could be attributed to lower cross sections of a significant fraction of seed nuclei located in the Bi and Pb region around the $N$=126 shell closure.Comment: 5 pages, 1 figure Proceedings "Nuclear Physics in Astrophysics NPA-III", Dresden/Germany (2007

Guanine derived porous carbonaceous materials : towards C₁N₁

Herein, we study the basic nature of noble covalent, sp2-conjugated materials prepared via direct condensation of guanine in the presence of an inorganic salt melt as structure directing agent. At temperatures below 700 °C stable and more basic addition products with at C:N ratio of 1 (C1N1 adducts) and with rather uniform micropore sizes are formed. Carbonization at higher temperatures breaks the structural motif, and N-doped carbons with 11 wt% and surface areas of 1900 m g-1 are obtained. The capability for CO2 sorption and catalytic activity of the materials depend of both their basicity and their pore morphology. The optimization of the synthetic parameters lead to very active (100% conversion) and highly selective (99% selectivity) heterogeneous base catalysts, as exemplified with the model Knoevenagel condensation of benzaldehyde with malononitrile. The high stability upon oxidation of these covalent materials and their basicity open new perspectives in heterogeneous organocatalysis

Visible-light induced emulsion photopolymerization with carbon nitride as stabilizer and photoinitiator

Photopolymerization is a common method in the synthesis of polymers with various applications. Herein, a simple and effective route for surfactant-free emulsion photopolymerization (EPP) under visible light irradiation is described. Therein, graphitic carbon nitride (g-CN) was utilized as an stabilizer and a photoinitiator at the same time. As such, g-CN provides the starting point for polymer chain growth and particle formation. Notably, the as-prepared polymer latexes are directly crosslinked by g-CN, and the existence of g-CN is confirmed inside of the particle, as well as outside, where it forms relatively stable latexes. Moreover, surface functionalized g-CN was utilized to tailor the g-CN/monomer interactions for improved particle formation. g-CN quantum dots with enhanced photoluminescence properties were introduced in EPP as well, providing polymer latexes with enhanced photoluminescence. The obtained polymer nanoparticles might be promising candidates for bioimaging applications