Reducing the radioactive doses of liquid samples taken from reprocessing plant vessels by volume reduction

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The real time mass evaluation system as a tool for detection of undeclared cascade operation at GCEPs

Given the flexibility of current cascade designs a real time mass monitoring system is preferred for safeguarding Gas Centrifuge Enrichment Plants. However, if such a system is to be installed in a GCEP it must not impinge on plant operation or be intrusive. Since load cells are already part of the operational process and located outside the cascade hall their exploitation for safeguards purposes is an obvious development. The paper describes, through dynamic simulations, how transients would be observed in real-time mass balances when undeclared cascade operation takes place in a declared facility

Identical Bands in Superdeformed Nuclei: A Relativistic Description

Relativistic Mean Field Theory in the rotating frame is used to describe superdeformed nuclei. Nuclear currents and the resulting spatial components of the vector meson fields are fully taken into account. Identical bands in neighboring Rare Earth nuclei are investigated and excellent agreement with recent experimental data is observed.Comment: 11 pages (Latex) and 4 figures (available upon request) TUM-ITP-Ko93/

Lifetime measurements of Triaxial Strongly Deformed bands in 163^{163}Tm

With the Doppler Shift Attenuation Method, quadrupole transition moments, $Q_t$, were determined for the two recently proposed Triaxial Strongly Deformed (TSD) bands in $^{163}$Tm. The measured $Q_t$ moments indicate that the deformation of these bands is larger than that of the yrast, signature partners. However, the measured values are smaller than those predicted by theory. This observation appears to be valid for TSD bands in several nuclei of the regionComment: 8 pages, 5 figures. Submitted to Physical Review

Evaluation and decentralised governance: Examples of inspections in polycentric education systems

Across Europe schools and other service providers increasingly operate in networks to provide inclusive education or develop and implement more localized school-to-school improvement models. As some education systems move towards more decentralized decision-making where multiple actors have an active role in steering and governing schools, the tasks and responsibilities of Inspectorates of Education must also change. This paper reflects on these changes and suggests ‘polycentric’ inspection models that fit such a decentralized context. Examples of inspection frameworks and methods from Northern Ireland, England and the Netherlands are provided, as well as a brief discussion of the potential impact of such ‘polycentric’ models

Expanding the scope of leaf symbiosis: Caballeronia endophytes in Empogona and Tricalysia (Coffeeae, Rubiaceae)

Leaf symbiosis is a remarkable phenomenon observed in Rubiaceae host plants, where they interact with bacterial endophytes residing within their leaves. Although approximately 650 species from 8 genera across 4 tribes exhibit this symbiosis, its fiill extent within Rubiaceae remains unknown. Our primary objective is to investígate the potential presence of leaf endophytes in the African plant genera Empogona and Tricalysia and, if confirmed, determine their identity. To accomplish this, we extracted total DNA from the leaves of four Coffeeae tribe species {Empogona congesta, Tricalysia hensii, T. lasiodelphys, and T. semidecidua) and sequenced it. Subsequently, we filtered out bacterial reads. Through phylogenetic analysis o f the endophytes, we were able to ascertain their identity and establish their relationship with known symbiotic organisms. Notably, all four species harboured non-nodulated leaf endophytes, specifically identified as Caballeronia. Although these endophytes are distinct from one another, they are related to other nodulated and non-nodulated endophytes. Interestingly, we did not observe any discemible phylogenetic or geographic pattems among the endophytes or their host plants. Our findings demónstrate the presence of Caballeronia endophytes in the leaves o f Empogona and Tricalysia, two genera previously not associated with leaf symbiosis. This interaction is likely to have a broader distribution, and further discoveries are inevitable in the future

Experimental acoustic modal analysis of an automotive cabin: Challenges and solutions

In this paper, a full Acoustic Modal Analysis (AMA) procedure to improve the CAE predictions of the car interior noise level is proposed. Some of the challenges that can be experienced during such an analysis are described and new solutions to face them are proposed. Particular AMA challenges range from the arrangement of the experimental setup to the post-processing analysis. Since a large number of microphones are needed, a smart localization procedure, which automatically determines the microphone three dimensional (3-D) positions and dramatically reduces the setup time, is presented herein. Furthermore, the need for a large number of sound sources spread across the cavity to assure a homogeneous sound field makes modal parameter estimation a nontrivial task. Traditional modal parameter estimators have indeed proven not to be effective in cases where many input excitation locations have to be used. Hence, a more suitable estimator, the Maximum Likelihood Modal Model-based (ML-MM) method, will be employed for such an analysis

Electronic structure of triangular, hexagonal and round graphene flakes near the Fermi level

The electronic shell structure of triangular, hexagonal and round graphene quantum dots (flakes) near the Fermi level has been studied using a tight-binding method. The results show that close to the Fermi level the shell structure of a triangular flake is that of free massless particles, and that triangles with an armchair edge show an additional sequence of levels ("ghost states"). These levels result from the graphene band structure and the plane wave solution of the wave equation, and they are absent for triangles with an zigzag edge. All zigzag triangles exhibit a prominent edge state at the Fermi level, and few low-energy conduction electron states occur both in triangular and hexagonal flakes due to symmetry reasons. Armchair triangles can be used as building blocks for other types of flakes that support the ghost states. Edge roughness has only a small effect on the level structure of the triangular flakes, but the effect is considerably enhanced in the other types of flakes. In round flakes, the states near the Fermi level depend strongly on the flake radius, and they are always localized on the zigzag parts of the edge