On the determination of anti-neutrino spectra from nuclear reactors

In this paper we study the effect of, well-known, higher order corrections to the allowed beta decay spectrum on the determination of anti-neutrino spectra resulting from the decays of fission fragments. In particular, we try to estimate the associated theory errors and find that induced currents like weak magnetism may ultimately limit our ability to improve the current accuracy and under certain circumstance could even largely increase the theoretical errors. We also perform a critical evaluation of the errors associated with our method to extract the anti-neutrino spectrum using synthetic beta spectra. It turns out, that a fit using only virtual beta branches with a judicious choice of the effective nuclear charge provides results with a minimal bias. We apply this method to actual data for U235, Pu239 and Pu241 and confirm, within errors, recent results, which indicate a net 3% upward shift in energy averaged anti-neutrino fluxes. However, we also find significant shape differences which can in principle be tested by high statistics anti-neutrino data samples.Comment: 20 pages, 5 figures, 9 tables, added references, version accepted for publication in Phys. Rev. C. Corrected errors in tab. 1 and eqs. 18 and 19. Results and conclusion unchange

Resonant diffraction gratings with polarization-dependent efficiencies

Subwavelength-structures with different fill factors in the lateral dimensions result in unique phase shifts for the different polarization states of transmitted light.By using this additional degree of freedom for diffractive optical elements, we yield additional functionalities for compact optical systems with DOEs. As a fully operable example we present a binary subwavelength-grating which acts as a polarizing beamsplitter for TE- and TM-polarization over a wide range of incidence angles. We show our design approach, the manufacturing process with Soft-UV-Nanoimprint-Technology, as well as experimental results. We will also lay out possibilities for the design and application of multilevel polarization-functionalized gratings

Кінетика сумісного виділення цинку і нікелю з розбавлених електролітів

Досліджені закономірності виділення цінку, нікелю і цинк-нікелевого сплаву з розведених електролітів, що містять в якості лігандів амінокислоту та аміак. Найкращі технологічні параметри та якість покрить отримані при спільному вмісті у розчині обох лігандів. Запропонований електроліт характеризується високою стабільністю, є технологічним та екологічно безпечним.The mechanisms of zinc, nickel and zinc-nickel alloy deposition from diluted electrolytes, containing amino acid or ammonia as a ligand, were investigated. The very technological characteristics and coatings quality were obtained if the electrolyte contained both of the ligands. The suggested electrolyte is characterized by high stability, processibility and it is ecologically safe

Nano-imprinted subwavelength gratings as polarizing beamsplitters

Polarizing beamsplitters have numerous applications in optical systems, such as systems for freeform surface metrology. They are classically manufactured from birefringent materials or with stacks of dielectric coatings. We present a binary subwavelength-structured form-birefringent diffraction grating, which acts as a polarizing beamsplitter for a wide range of incidence angles -30°…+30°. We refine the general design method for such hybrid gratings. We furthermore demonstrate the manufacturing steps with Soft-UV-Nanoimprint-Lithography, as well as the experimental verification, that the structure reliably acts as a polarizing beamsplitter. The experimental results show a contrast in efficiency for TE- and TM-polarization of up to 1:18 in the first order, and 34:1 in the zeroth order. The grating potentially enables us to realize integrated compact optical measurement systems, such as common-path interferometers

Multi-body simulation of a canine hind limb: model development, experimental validation and calculation of ground reaction forces

<p>Abstract</p> <p>Background</p> <p>Among other causes the long-term result of hip prostheses in dogs is determined by aseptic loosening. A prevention of prosthesis complications can be achieved by an optimization of the tribological system which finally results in improved implant duration. In this context a computerized model for the calculation of hip joint loadings during different motions would be of benefit. In a first step in the development of such an inverse dynamic multi-body simulation (MBS-) model we here present the setup of a canine hind limb model applicable for the calculation of ground reaction forces.</p> <p>Methods</p> <p>The anatomical geometries of the MBS-model have been established using computer tomography- (CT-) and magnetic resonance imaging- (MRI-) data. The CT-data were collected from the pelvis, femora, tibiae and pads of a mixed-breed adult dog. Geometric information about 22 muscles of the pelvic extremity of 4 mixed-breed adult dogs was determined using MRI. Kinematic and kinetic data obtained by motion analysis of a clinically healthy dog during a gait cycle (1 m/s) on an instrumented treadmill were used to drive the model in the multi-body simulation.</p> <p>Results and Discussion</p> <p>As a result the vertical ground reaction forces (z-direction) calculated by the MBS-system show a maximum deviation of 1.75%BW for the left and 4.65%BW for the right hind limb from the treadmill measurements. The calculated peak ground reaction forces in z- and y-direction were found to be comparable to the treadmill measurements, whereas the curve characteristics of the forces in y-direction were not in complete alignment.</p> <p>Conclusion</p> <p>In conclusion, it could be demonstrated that the developed MBS-model is suitable for simulating ground reaction forces of dogs during walking. In forthcoming investigations the model will be developed further for the calculation of forces and moments acting on the hip joint during different movements, which can be of help in context with the <it>in silico </it>development and testing of hip prostheses.</p

Numerical investigations on the strain-adaptive bone remodelling in the periprosthetic femur: Influence of the boundary conditions

© 2009 Behrens et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Guidelines for Aspen Restoration in Utah with Applicability to the Intermountain West

As highly productive and biologically diverse communities, healthy quaking aspen (Populus tremuloides; hereafter aspen) forests provide a wide range of ecosystem services across western North America. Western aspen decline during the last century has been attributed to several causes and their interactions, including altered fire regimes, drought, excessive use by domestic and wild ungulates, and conifer encroachment. Today’s managers need science-based guidance to develop and implement strategies and practices to restore structure, processes, and resilience to the full range of aspen functional types across multiple spatial scales. In these guidelines, we detail a process for making step-by-step decisions about aspen restoration. The steps are: (1) assessment of aspen condition, (2) identification of problematic conditions, (3) determination of causal factors, (4) selection of appropriate response options, (5) monitoring for improvement, and (6) assessment and adaptation. We describe the need for reference areas in which the full range of natural environmental conditions and ecosystem processes associated with aspen can be observed and quantified, and provide a list of example sites for Utah. These guidelines provide a road map for decision-makers to adaptively manage aspen in a time of increasing environmental stress and in anticipation of an uncertain future

Application and Analysis of a Salt Bridge Reference Electrode Setup for PEM Water Electrolysis: Towards an Extended Voltage Loss Break Down

Information on PEMWE performance is often obtained from full cell measurements. The level of detail of this information is, however, comparably low. This contribution analyzes kinetic parameters for anode and cathode reactions separately as a step towards an extended loss breakdown through a salt bridge reference electrode. The reference electrode setup is shown in detail, and qualitative measurements are discussed. OER and HER Tafel slopes and exchange current densities for both reactions are reported. An outlook on future use cases for the salt bridge reference electrode is given and supported by measurement data

Wear Behavior of MoS2 Lubricant Layers during Sheet Metal Forming

The increased use of high and ultra-high strength steel and materials with a high adhesion tendency leads to higher demands regarding the wear resistance of forming tools. A promising approach addressing both challenges is to apply MoS2 dry film lubricant coating systems to the tool surface. These coatings reduce friction and the use of drawing oils and can also be used as an abherent. Once these coatings are exhausted, they can be chemically removed and reapplied. However, the tool life of the coatings cannot be predicted properly, due to their inhomogeneous wear behavior which depends on the forming parameters and differs locally. Moreover, there are carryover effects of MoS2-particles to already ablated areas. Given the unpredictability of the wear of dry film lubricant coatings, it is not possible to plan the recoating cycles appropriately and thus, the potential of these coatings for commercial applications is limited. In this research, the wear behavior of MoS2-layers in deep drawing processes was investigated on a test stand with DP800+Z coil material which ensures realistic load conditions at the draw ring radius. Firstly, the wear pattern was determined and locally different contact pressures were recorded and assigned to respective wear areas. Due to bending effects of the sheet material, there are two major areas of wear on the draw ring radius. During wear tests, the wear-dependent coating thickness during wear initiation was determined by using 3D laser scanning microscopy and the friction force was evaluated. © 2017 The Authors.European Research Association for Sheet Metal Working (EFB)German Federation of Industrial Research Associations (AiF)Federal Ministry of Economic Affairs and Energy (BMWi