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Uncertainty of determination of 158Tb in the RBMK nuclear reactor waste

The activity of 158Tb was measured in waste samples from the Ignalina NPP Unit I RBMK-1500 reactor using gamma-ray spectrometry. The origin of 158Tb and the other observed gamma-ray emitters has been studied by using SCALE 6.1 modeling and comparing radionuclide ratios in the RBMK-1500 radioactive waste. The results of the calculation of the massic activity of gamma-ray emitters were used for inte

Generation of RBMK-1500 spent nuclear fuel one-group cross-section libraries and their evaluation against experimental data

Depletion of RBMK-1500 spent nuclear fuel (SNF) with and without an erbium burnable absorber was modelled, and onegroup burn-up dependent cross-section libraries for Origen-ARP were created. Depletion calculations for the generation of crosssection libraries were performed using the SCALE 6.1 code package with the TRITON control module, which employs the NEWT deterministic 2D transport code with t

System Simulation of Partially Premixed Combustion in Heavy-Duty Engines : Gas Exchange, Fuels and In-cylinder Analysis

The concept of partially premixed combustion (PPC), applied to conventional diesel engines, has shown to yield high gross efficiencies and low emissions of oxides of nitrogen and soot. PPC emerged from the knowledge gained from homogeneous charge compression ignition (HCCI) research. To extend the load range and thus reduce cylinder pressure rise rates, the fuel is directly injected during the comThe concept of partially premixed combustion (PPC), applied to conventional diesel engines, has shown to yield high gross efficiencies and low emissions of oxides of nitrogen and soot. PPC emerged from the knowledge gained from homogeneous charge compression ignition (HCCI) research. To extend the load range and thus reduce cylinder pressure rise rates, the fuel is directly injected during the com

Actinides input to the dose in the irradiated graphite of RBMK-1500 reactor

The purpose of this work is to indicate the actinides input to the total radiation dose caused by the irradiated graphite of the RBMK-1500 reactor in comparison to the dose delivered by other nuclides. We used computer codes (SCALE 6.1 and MCNPX 2.7) to estimate the dose rate delivered by actinides giving special attention to the 244 Cm isotope as a critical contributor to the total activity of

Actinide-only and full burn-up credit in criticality assessment of RBMK-1500 spent nuclear fuel storage cask using axial burn-up profile

Safe long-term storage of spent nuclear fuel (SNF) is one of the main issues in the field of nuclear safety. Burn-up credit application in criticality analysis of SNF reduces conservatism of usually used fresh fuel assumption and implies a positive economic impact for the SNF storage. Criticality calculations of spent nuclear fuel in the CONSTOR® RBMK-1500/M2 cask were performed using pre-generat

Actinides in irradiated graphite of RBMK-1500 reactor

The activation of graphite in the nuclear power plants is the problem of high importance related with later graphite reprocessing or disposal. The activation of actinide impurities in graphite due to their toxicity determines a particular long term risk to waste management. In this work the activation of actinides in the graphite constructions of the RBMK-1500 reactor is determined by nuclear spec

Energy efficient and moisture safe row houses in Sweden

This project consists of a thorough study of an energy efficient and moisture safe row-house, located in the Nordic climate of Sweden. Climate and site analysis, building scale design decisions and finally the evaluation and optimization of its energy performance were different steps of a holistic process aiming at the architectural quality, energy efficiency, comfort and the well-being of users.

Daylight compliance of Swedish residential blocks according to past and current performance criteria

The importance of daylight to occupants’ health and wellbeing has been extensively documented, as well as its role in reducing electric lighting use. As a result, most countries have today some form of regulatory framework, specifying minimum daylight requirements for built spaces. The present Swedish building code (BBR – BFS 2011:6) includes general recommendations for daylight provision of resid

Regulator of G-protein signaling 5 regulates the shift from perivascular to parenchymal pericytes in the chronic phase after stroke

Poststroke recovery requires multiple repair mechanisms, including vascular remodeling and blood-brain barrier (BBB) restoration. Brain pericytes are essential for BBB repair and angiogenesis after stroke, but they also give rise to scar-forming platelet-derived growth factor receptor β (PDGFR-β)–expressing cells. However, many of the molecular mechanisms underlying this pericyte response after st

Tool Life and Cutting Data Modelling in Metal Cutting : Testing, Modelling and Cost Performance

One of the most important production processes in industry is metal cutting. If a product is not a machined metal part, it is likely that the mould, die and tools used to produce the product or parts of the product are machined. The tools, machines and time spent add to the cost of the finished product and both industry and academia spend considerable effort in increasing efficacy and minimizing t

Early-holocene vegetation of northern Iceland : Pollen and plant macrofossil evidence from the Skagi peninsula

Pollen and plant macrofossil records from two lakes on northernmost Skagi peninsula, northern Iceland, reflect a progressive closing of the vegetation cover during the early Holocene. This development was connected with the succession from an initial herb-tundra phase characterized by Oxyria digyna, Poaceae and Caryophyllaceae, through an intermediate dwarf-shrub phase dominated by Salix and Empet

Biostratigraphic Evidence of the Allerød-Younger Dryas-Preboreal Oscillation in Northern Iceland

Basal sediments of Lake Torfadalsvatn, northern Iceland, record changes in terrestrial and limnic environments in the period 11,300-9000 14C yr B.P. These changes were probably forced by climate and connected with displacements of the marine polar front and sea-ice margin. Pollen, spores, green algae (Pediastrum), saturation isothermal remanent magnetization, and carbon content of the basal sedime

Dynamic sea-level change during the last deglaciation of northern Iceland

A detailed reconstruction of deglacial relative sea-level changes at the northern coast of Iceland, based on the litho- and biostratigraphy of lake basins, indicates an overall fall in relative sea level of about 45 m between 11 300 and 9100 BP, corresponding to an isostatic rebound of 77 m. The overall regression was interrupted by two minor transgressions during the late Younger Dryas and in ear

Leaf metabolic and morphological responses of dwarf willow (Salix herbacea) in the sub-arctic to the past 9000 years of global environmental change

Ice-core records of the concentration of atmospheric CO2 and its stable isotope ratio (δ13C(a)) have shown that the global C cycle has not remained in steady-state over the past 11000 yr, implying a possible change in vegetation activity over this period. Here we evaluated the ecophysiological responses of the dwarf willow (Salix herbacea) over the past 9000 yr by measuring the stable carbon isoto

Plant survival in Iceland during periods of glaciation?

Aim: The paper addresses the classical question of possible plant survival in Iceland during the last glacial period in the light of a palaeobotanical record from northern Iceland, spanning the period 11,300-9000 BP, including the Younger Dryas stadial. We review the Late Cenozoic fossil plant record, the past debate on glacial plant refugia in Iceland, and the evidence for ice-free areas during t

What can be learned from practical cases of green economy? –studies from five European countries

The transition to green economies has been mediated by concrete cases and experiments in a variety of different industrial and social sectors. What is lacking, is research that would synthesize key findings and “lessons learned” across a variety of cases. In this study, we explore ten cases of green economy of different sectors and approaches from five European countries and identify factors that