Publications related to Nuclear chain reaction

Atomic level insight into irradiation effects in nuclear fuel materials

Microstructural evolution during in-pile irradiation, radiation damage effects and fission products behavior in UO2 nuclear fuel are key issues in understanding and for the modeling of the performance as well as safety characteristics of nuclear fuels in t ...

EPFL2024

Neutron-Gamma Noise Measurements in a Zero-Power Reactor Using Organic Scintillators

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari

Noise measurements in light water reactor systems aid in generating validation data for integral point kinetic parameter predictions and generating monitoring parameters for reactor safety and safeguards. The CROCUS zero-power reactor has been used to supp ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Filiform Variable Stiffness Technologies for Medical Robotics

Yegor Piskarev

In recent years, soft robotics has surged in applications like wearables, drones, smart fabrics, and medical instruments. Due to their compliance, these devices excel in tasks demanding dexterity and adaptability, such as manipulation, locomotion, crash re ...

EPFL2024

Recent progress in calcium looping integrated with chemical looping combustion (CaL-CLC) using bifunctional CaO/CuO composites for CO2 capture: A state-of-the-art review

Oliver Kröcher, Muhammad Awais Naeem, Yuxin Ma, Hui Zhou, Hongyu Zhu

Calcium looping integrated with chemical looping combustion (CaL-CLC) process is an efficient and cost-effective CO2 capture technology. In this technique, the heat generated by chemical looping combustion of CuO is used insitu to calcine CaCO3, thus avoid ...

ELSEVIER SCI LTD2023

HighNESS conceptual design report: Volume II. The NNBAR experiment

Mina Akhyani, Xiaoxue Han, Davide Campi, Sheng Xu

A key aim of the HighNESS project for the European Spallation Source is to enable cutting-edge particle physics experiments. This volume presents a conceptual design report for the NNBAR experiment. NNBAR would exploit a new cold lower moderator to make th ...

Ios Press2023

Extension of the OFFBEAT fuel performance code to finite strains and validation against LOCA experiments

Andreas Pautz, Carlo Fiorina, Alessandro Scolaro, Edoardo Luciano Brunetto

The mechanical analysis of nuclear fuel behavior under base-irradiation conditions has traditionally been performed adopting the small-strain approximation. However, many cases of interest for fuel behavior involve the occurrence of large rod deformations ...

ELSEVIER SCIENCE SA2023

Influence of temperature on phase assemblages of belite-ye'elimite cement

Karen Scrivener, Barbara Lothenbach, Natechanok Chitvoranund, Diana Londoño Zuluaga

This paper studies the effect of temperature on the phase assemblages of belite-ye'elimite cement. A comparison is made between thermodynamic modelling and experimental data at 28 and 180 days of hydration at 5, 20, 40, and 60 degrees C. The fast reaction ...

Pergamon-Elsevier Science Ltd2023

Reactivity of Bromine Radical with Dissolved Organic Matter Moieties and Monochloramine: Effect on Bromate Formation during Ozonation

Urs von Gunten, Sung Eun Lim

Bromine radical (Br center dot) has been hypothesized to be a key intermediate of bromate formation during ozonation. Once formed, Br center dot further reacts with ozone to eventually form bromate. However, this reaction competes with the reaction of Br c ...

AMER CHEMICAL SOC2023

RDS: FPGA Routing Delay Sensors for Effective Remote Power Analysis Attacks

Mirjana Stojilovic, Ognjen Glamocanin, David Spielmann

State-of-the-art sensors for measuring FPGA voltage fluctuations are time-to-digital converters (TDCs). They allow detecting voltage fluctuations in the order of a few nanoseconds. The key building component of a TDC is a delay line, typically implemented ...

2023

A concept for the extraction of the most refractory elements at CERN-ISOLDE as carbonyl complex ions

João Pedro Fernandes Pinto Ramos

We introduce a novel thick-target concept tailored to the extraction of refractory 4d and 5d transition metal radionuclides of molybdenum, technetium, ruthenium and tungsten for radioactive ion beam production. Despite the more than 60-year old history of ...

2022

High accuracy measurement of the prompt neutron decay constant in CROCUS using Gamma Noise and bootstrapped uncertainties

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari, Pavel Frajtag, Tom Mager

We experimentally demonstrate the advantages of gamma detection for noise measurements to deter-mine the prompt neutron decay constant a of a nuclear reactor using the power spectral density (PSD) method, coupled to a new uncertainty estimation scheme base ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Data-Driven Predictive Models: Calculational Bias in Characterization of Spent Nuclear Fuel

Characteristics of the spent nuclear fuel (SNF) are typically calculated, requiring validation a priori. The validation process relies on the difference between calculations and measurements, namely the bias. Usually, predicting the bias based on benchmark ...

EPFL2022

Towards the Validation of Noise Experiments in the CROCUS Reactor Using the TRIPOLI-4 Monte Carlo Code in Analog Mode

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari

Intrinsic neutron noise experiments offer a non-invasive manner to measure the prompt decay constant or reactivity of fissile systems. Using the fluctuations in the density of fission chains, one can infer the kinetics parameters via correlation analysis s ...

2021

Growth and viability of microorganisms in bentonite and their potential activity in deep geological repository environments

Niels Burzan

Radioactive waste is among the most dangerous anthropogenic waste and its safe disposal is a challenging multi-generational task. Many nations have sought for the peaceful application of nuclear fission for the reliable production of electric energy to pow ...

EPFL2021

Delayed gamma fraction determination in the zero power reactor CROCUS

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari, Pavel Frajtag, Tom Mager

Gamma rays are an inextricable part of a nuclear reactor's radiation field, and as such require characterization for dose rate estimations required for the radiation protection of personnel, material choices, and the design of nuclear facilities. Most comm ...

EDP SCIENCES S A2021

Circadian dynamics of RNA localisation in the mammalian liver

Clémence Yumie Syloun Hurni

Gene expression in eukaryotes is a complex multi-step process. It starts in the nucleus with transcription, the synthesis of a mRNA copy from a DNA template. While in the nucleus, the RNA transcript is subject to multiple co- and post-transcriptional modif ...

EPFL2021

The COLIBRI experimental program in the CROCUS reactor: characterization of the fuel rods oscillator

Andreas Pautz, Vincent Pierre Lamirand, Mathieu Hursin, Carlo Fiorina, Oskari Ville Pakari, Pavel Frajtag, Axel Guy Marie Laureau, Adolfo Rais, Daniel Godat

The present article presents the mechanical characterization of the fuel rods oscillator developed for the purposes of the COLIBRI experimental program in CROCUS. COLIBRI aims at investigating the radiation noise related to fuel vibrations. The main motiva ...

2020

Artificial Neural Networks as Surrogate Models for Uncertainty Quantification and Data Assimilation in 2-D/3-D Fuel Performance Studies

Andreas Pautz, Mathieu Hursin, Carlo Fiorina, Alessandro Scolaro, Daniel Jerôme Siefman

This paper preliminarily investigates the use of data-driven surrogates for fuel performance codes. The objective is to develop fast-running models that can be used in the frame of uncertainty quantification and data assimilation studies. In particular, da ...

2020

Preliminary design and analysis of Liquid Fuel Molten Salt Reactor using multi-physics code GeN-Foam

Carlo Fiorina

In this study, a hypothetical fast spectrum Liquid Fuel Molten Salt Reactor (LFMSR) core is modeled using the multiphysics C++ code GeN-Foam (General Nuclear Foam). GeN-Foam is based on OpenFOAM, a C++ opensource library for solution of continuum mechanics ...

ELSEVIER SCIENCE SA2020

Uncertainty and sensitivity analysis of PWR mini-core transients in the presence of nuclear data uncertainty using non-parametric tolerance limits

Andreas Pautz, Winfried Zwermann, Alexander Aures

The impact of nuclear data uncertainties is studied for the reactor power and the reactivity during control rod withdrawal transients with reactivity insertions of 0.5

and 0.97

, respectively, for a PWR mini-core model. Multi-group cross sections, the mul ...

PERGAMON-ELSEVIER SCIENCE LTD2020