Application of in-situ gamma spectrometry in the remediation of radioactively contaminated soil

The Fernald Environmental Management Project (FEMP) is a US Department of Energy site that is undergoing total remediation and closure. Most of the remediation effort entails massive excavation of soil for disposal, both offsite and onsite, at an engineered disposal facility. In-situ gamma spectrometry is routinely used to support soil excavation operations to accurately and quickly identify soil areas as being above or below regulatory remediation criteria. Two different in-situ gamma spectrometry systems are used. The first is a sodium iodide (NaI) detector mounted either on a tractor or a jogging stroller, depending on the terrain to be measured. The NaI system allows the collection of a gamma energy spectrum which can be analyzed to identify and quantify radioactive isotopes which are present within the detector`s viewing area. Each energy spectrum is tagged by location coordinates provided by an on-board global positioning system (GPS) to precisely locate elevated contamination areas. The second is a tripod-mounted, high purity germanium detector (HPGe) gamma spectrometry system that is functionally similar to the NaI system. The principal advantage of the HPGe is its superior resolution, which allows much more accurate identification and quantification of radionuclide contaminants in soils. In order to effectively utilize the data quality objective process with these systems, three quality assurance (QA) elements had to be performed

Atomistic Studies of Defect Nucleation during Nanoindentation of Au (001)

Atomistic studies are carried out to investigate the formation and evolution of defects during nanoindentation of a gold crystal. The results in this theoretical study complement the experimental investigations [J. D. Kiely and J. E. Houston, Phys. Rev. B, v57, 12588 (1998)] extremely well. The defects are produced by a three step mechanism involving nucleation, glide and reaction of Shockley partials on the {111} slip planes noncoplanar with the indented surface. We have observed that slip is in the directions along which the resolved shear stress has reached the critical value of approximately 2 GPa. The first yield occurs when the shear stresses reach this critical value on all the {111} planes involved in the formation of the defect. The phenomenon of strain hardening is observed due to the sessile stair-rods produced by the zipping of the partials. The dislocation locks produced during the second yield give rise to permanent deformation after retraction.Comment: 11 pages, 13 figures, submitted to Physical Review

A IMPORTÂNCIA DA REDE DE CONHECIMENTO PARA A CONSTRUÇÃO DE CONHECIMENTO E INTELIGÊNCIA EM ENTIDADES DE CLASSE COMO FERRAMENTA DE INOVAÇÃO: UM ESTUDO DE CASO NA ACIM

RESUMO: Considerar as redes de conhecimento, constituídas por fontes e fluxos no contexto organizacional, pode possibilitar um melhor aproveitamento das informações e conhecimentos enquanto recursos. Ao considerar a gestão desses recursos as organizações passam ser capazes de obter maior competitividade. Para tanto, as organizações devem mapear as suas fontes e fluxos de informacionais com o intuito de conhecer melhor sua rede que permite a construção de conhecimentos e inteligências.  A presente pesquisa foi realizada na Associação Comercial e Industrial de Marília (ACIM), uma importante entidade de classe da cidade de Marília, no estado de São Paulo. Por meio do uso do método de estudo de caso, foi possível mapear as fontes e fluxos de informações e conhecimentos, que somadas constroem a rede conhecimento da ACIM. Como resultado, construiu-se um sociograma que demonstra as relações entre sujeitos e organizações, do ambiente interno e externo. Com isso demonstrou-se como o conhecimento e a inteligência sãos construídas. Identificou-se que as informações e conhecimentos estão centralizados nos sujeitos do nível tático, bem como, existe pouca percepção das fontes e fluxos externos, resultando no não aproveitamento pleno desses recursos. A pesquisa é concluída com recomendações para ACIM fazer um melhor uso desses recursos de maneira estruturada.Palavras-Chave: Redes de Conhecimento; Conhecimento; Informação; Inteligência; ACIM; Entidade de Classe. ABSTRACT: Considering knowledge networks, constituted by sources and flows in the organizational context, can enable a better use of information and knowledge as resources. When considering the management of these resources, organizations are now able to achieve greater competitiveness. To this end, organizations must map their sources and flows of information in order to better understand their network that allows the construction of knowledge and intelligence. This research was carried out at the Commercial and Industrial Association of Marília (ACIM), an important class entity in the city of Marília, in the state of São Paulo. Using the case study method, it was possible to map the sources and flows of information and knowledge, which together build the ACIM knowledge network. As a result, a sociogram was built that demonstrates the relationships between subjects and organizations, from the internal and external environment. This demonstrated how knowledge and intelligence are built. It was identified that the information and knowledge are centralized in the subjects at the tactical level, as well as, there is little perception of external sources and flows, resulting in the failure to make full use of these resources. The survey concludes with recommendations for ACIM to make better use of these resources in a structured manner.Keywords: Knowledge Networks; Knowledge; Information; Intelligence; ACIM; Class Entity. RESUMEN: Considerar las redes de conocimiento, constituidas por fuentes y flujos en el contexto organizacional, puede permitir un mejor uso de la información y el conocimiento como recursos. Al considerar la gestión de estos recursos, las organizaciones ahora pueden lograr una mayor competitividad. Con este fin, las organizaciones deben mapear sus fuentes y flujos de información para comprender mejor su red que permite la construcción de conocimiento e inteligencia. Esta investigación se llevó a cabo en la Asociación Comercial e Industrial de Marília (ACIM), una importante entidad de clase en la ciudad de Marília, en el estado de São Paulo. Utilizando el método de estudio de caso, fue posible mapear las fuentes y los flujos de información y conocimiento, que juntos crean la red de conocimiento ACIM. Como resultado, se construyó un sociograma que demuestra las relaciones entre sujetos y organizaciones, desde el entorno interno y externo. Esto demostró cómo se construyen el conocimiento y la inteligencia. Se identificó que la información y el conocimiento están centralizados en los temas a nivel táctico, así como también hay poca percepción de fuentes y flujos externos, lo que resulta en la falla en el uso completo de estos recursos. La encuesta concluye con recomendaciones para que ACIM haga un mejor uso de estos recursos de manera estructurada.Palabras clave: Redes de conocimiento; Conocimiento; Información; Inteligencia; ACIM; Entidad de clase.

Growth of oriented C11b MoSi2 bicrystals using a modified Czochralski technique

Oriented bicrystals of pure C11b MoSi2 have been grown in a tri-arc furnace using the Czochralski technique. Two single crystal seeds were used to initiate the growth. Each seed had the orientation intended for one of the grains of the bicrystals, which resulted in a 60° twist boundary on the (110) plane. Seeds were attached to a water-cooled seed rod, which was pulled at 120 mm/h with the seed rod rotating at 45 rpm. The water- cooled copper hearth was counter-rotated at 160 rpm. Asymmetric growth ridges associated with each seed crystal were observed during growth and confirmed the existence of a bicrystal. It was also found that careful alignment of the seeds was needed to keep the grain boundary from growing out of the boule. The resulting boundary was characterized by imaging and crystallographic techniques in a scanning electron microscope. The boundary was found to be fairly sharp and the misorientation between the grains remained within 2° from the disorientation between the seeds

Soft Photons in Hadron-Hadron Collisions: Synchrotron Radiation from the QCD Vacuum?

We discuss the production of soft photons in high energy hadron-hadron collisions. We present a model where quarks and antiquarks in the hadrons emit ``synchrotron light'' when being deflected by the chromomagnetic fields of the QCD vacuum, which we assume to have a nonperturbative structure. This gives a source of prompt soft photons with frequencies $\omega <= 300 MeV$ in the c.m. system of the collision in addition to hadronic bremsstrahlung. In comparing the frequency spectrum and rate of ``synchrotron'' photons to experimental results we find some supporting evidence for their existence. We make an exclusive--inclusive connection argument to deduce from the ``synchrotron'' effect a behaviour of the neutron electric formfactor $G_E^n(Q^2)$ proportional to $(Q^2)^{1/6}$ for $Q^2 < 20 fm^{-2}$. We find this to be consistent with available data. In our view, soft photon production in high energy hadron-hadron and lepton-hadron collisions as well as the behaviour of electromagnetic hadron formfactors for low $Q^2$ are thus sensitive probes of the nonperturbative structure of the QCD vacuum.Comment: Heidelberg preprint HD-THEP-94-36, 31 pages, LaTeX + ZJCITE.sty (included), 12 figures appended as uuencoded compressed ps-fil

Pion Content of the Nucleon as seen in the NA51 Drell-Yan experiment

In a recent CERN Drell-Yan experiment the NA51 group found a strong asymmetry of $\bar u$ and $\bar d$ densities in the proton at $x\simeq0.18$. We interpret this result as a decisive confirmation of the pion-induced sea in the nucleon.Comment: 10 pages + 3 figures, Preprint KFA-IKP(TH)-1994-14 .tex file. After \enddocument a uu-encodeded Postscript file comprising the figures is appende

HMO Participation in Medicare+Choice

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75542/1/j.1530-9134.2005.00073.x.pd

Meson Cloud of the Nucleon in Polarized Semi-Inclusive Deep-Inelastic Scattering

We investigate the possibility of identifying an explicit pionic component of the nucleon through measurements of polarized $\Delta^{++}$ baryon fragments produced in deep-inelastic leptoproduction off polarized protons, which may help to identify the physical mechanism responsible for the breaking of the Gottfried sum rule. The pion-exchange model predicts highly correlated polarizations of the $\Delta^{++}$ and target proton, in marked contrast with the competing diquark fragmentation process. Measurement of asymmetries in polarized $\Lambda$ production may also reveal the presence of a kaon cloud in the nucleon.Comment: 23 pages REVTeX, 7 uuencoded figures, accepted for publication in Zeit. Phys.

Block bond-order potential as a convergent moments-based method

The theory of a novel bond-order potential, which is based on the block Lanczos algorithm, is presented within an orthogonal tight-binding representation. The block scheme handles automatically the very different character of sigma and pi bonds by introducing block elements, which produces rapid convergence of the energies and forces within insulators, semiconductors, metals, and molecules. The method gives the first convergent results for vacancies in semiconductors using a moments-based method with a low number of moments. Our use of the Lanczos basis simplifies the calculations of the band energy and forces, which allows the application of the method to the molecular dynamics simulations of large systems. As an illustration of this convergent O(N) method we apply the block bond-order potential to the large scale simulation of the deformation of a carbon nanotube.Comment: revtex, 43 pages, 11 figures, submitted to Phys. Rev.

Field inter-comparison of eleven atmospheric ammonia measurement techniques

Eleven instruments for the measurement of ambient concentrations of atmospheric ammonia gas (NH3), based on eight different measurement methods were inter-compared above an intensively managed agricultural field in late summer 2008 in Southern Scotland. To test the instruments over a wide range of concentrations, the field was fertilised with urea midway through the experiment, leading to an increase in the average concentration from 10 to 100 ppbv. The instruments deployed included three wet-chemistry systems, one with offline analysis (annular rotating batch denuder, RBD) and two with online-analysis (Annular Denuder sampling with online Analysis, AMANDA; AiRRmonia), two Quantum Cascade Laser Absorption Spectrometers (a large-cell dual system; DUAL-QCLAS, and a compact system; c-QCLAS), two photo-acoustic spectrometers (WaSul-Flux; Nitrolux-100), a Cavity Ring Down Spectrosmeter (CRDS), a Chemical Ionisation Mass Spectrometer (CIMS), an ion mobility spectrometer (IMS) and an Open-Path Fourier Transform Infra-Red (OP-FTIR) Spectrometer. The instruments were compared with each other and with the average concentration of all instruments. An overall good agreement of hourly average concentrations between the instruments (R2>0.84), was observed for NH3 concentrations at the field of up to 120 ppbv with the slopes against the average ranging from 0.67 (DUAL-QCLAS) to 1.13 (AiRRmonia) with intercepts of −0.74 ppbv (RBD) to +2.69 ppbv (CIMS). More variability was found for performance for lower concentrations (<10 ppbv). Here the main factors affecting measurement precision are (a) the inlet design, (b) the state of inlet filters (where applicable), and (c) the quality of gas-phase standards (where applicable). By reference to the fast (1 Hz) instruments deployed during the study, it was possible to characterize the response times of the slower instruments