scholarly journals TCAD AND SPICE MODELING OF SILICON VLSI ELEMENTS TAKING INTO ACCOUNT FOR TEMPERATURE, RADIATION AND AGING EFFECTS

2021 ◽  
Author(s):  
Konstantin Petrosyants
Keyword(s):  
Radiation Effects ◽  
Aging Effects ◽  
Term Operation ◽  
Wide Range ◽  
Temperature Radiation ◽  
Silicon Vlsi

RAD-THERM-AGING versions of TCAD and SPICE models have been developed for BiCMOS VLSI components with submicron and nanometer sizes, taking into account for various types of radiation effects, temperatures in the wide range of -260°C…+300°C and aging during long-term operation.

scholarly journals Results of Analysis of Aging Related Events at Ukrainian NPPs

2020 ◽  
pp. 44-51
Author(s):  
O-i Shugailo ◽  
O. Ligotskyy ◽  
O. Pecherytsia ◽  
O. Kulman ◽  
R. Moskalyshyn ◽  
...  
Keyword(s):  
Nuclear Energy ◽  
Maximum Efficiency ◽  
Operational Experience ◽  
Aging Effects ◽  
Term Operation ◽  
Operation Period ◽  
Periodic Safety ◽  
Nuclear Installation ◽  
Main Factors

The design lifetime (30 years) of Ukrainian NPPs has already been expired or will be expired soon. One of the priority areas for the development of nuclear energy is long-term operation (LTO) based on the results of periodic safety review. At present, eleven Ukrainian NPP units are operated under LTO conditions, which in turn causes certain features of operation related to wear, fatigue and general aging of components and structures. An issue of aging management is considered one of the main factors to ensure the safety of a nuclear installation, both in the design lifetime and in the long-term operation. The primary purpose of aging management is to ensure the safety and maximum efficiency of operation through the implementation of technically and economically feasible measures aimed at timely detection and keeping of degradation of NPP components caused by aging within the limits. One way to determine the efficiency of implemented measures and aging management programs is to analyze operational experience and, in particular, analyze the number of NPP operational occurrences during the design and long-term operation period and that are directly related to the aging effects. This paper presents the results of the analysis of the events at Ukrainian NPPs caused by aging processes, compares the results of national and international experience.

Semi-automated operation of Mars Climate Simulation chamber – MCSC modelled for biological experiments

2016 ◽  
Vol 16 (4) ◽  
pp. 328-342
Author(s):  
M.V. Tarasashvili ◽  
Sh.A. Sabashvili ◽  
S.L. Tsereteli ◽  
N.D. Aleksidze ◽  
O. Dalakishvili
Keyword(s):  
Building Materials ◽  
Genetically Modified Organisms ◽  
Space Station ◽  
Climate Simulation ◽  
Term Operation ◽  
Space Suits ◽  
Atmosphere Temperature ◽  
Temperature Radiation ◽  
Simulation Chamber

AbstractThe Mars Climate Simulation Chamber (MCSC) (GEO PAT 12 522/01) is designed for the investigation of the possible past and present habitability of Mars, as well as for the solution of practical tasks necessary for the colonization and Terraformation of the Planet. There are specific tasks such as the experimental investigation of the biological parameters that allow many terrestrial organisms to adapt to the imitated Martian conditions: chemistry of the ground, atmosphere, temperature, radiation, etc. MCSC is set for the simulation of the conduction of various biological experiments, as well as the selection of extremophile microorganisms for the possible Settlement, Ecopoesis and/or Terraformation purposes and investigation of their physiological functions. For long-term purposes, it is possible to cultivate genetically modified organisms (e.g., plants) adapted to the Martian conditions for future Martian agriculture to sustain human Mars missions and permanent settlements. The size of the chamber allows preliminary testing of the functionality of space-station mini-models and personal protection devices such as space-suits, covering and building materials and other structures. The reliability of the experimental biotechnological materials can also be tested over a period of years. Complex and thorough research has been performed to acquire the most appropriate technical tools for the accurate engineering of the MCSC and precious programmed simulation of Martian environmental conditions. This paper describes the construction and technical details of the equipment of the MCSC, which allows its semi-automated, long-term operation.

Fracture Toughness Predictive Models Within the SOTERIA EU Project

2018 ◽  
Author(s):  
P. M. James ◽  
M. Berveiller
Keyword(s):  
Cleavage Fracture ◽  
Nuclear Power ◽  
Power Plants ◽  
Radiation Effects ◽  
Austenitic Stainless Steels ◽  
Irradiation Damage ◽  
Tensile Behaviour ◽  
Horizon 2020 ◽  
Term Operation

SOTERIA is focused on the ‘safe long term operation of light water reactors’. This will be achieved through an improved understanding of radiation effects in nuclear structural materials. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under agreement No 661913. The overall aim of the SOTERIA project is to improve the understanding of the ageing phenomena occurring in ferritic reactor pressure vessel steels and in the austenitic internals in order to provide crucial information to regulators and operators to ensure safe long-term operation (LTO) of existing European nuclear power plants (NPPs). SOTERIA has set up a collaborative research consortium which gathers the main European research centers and industrial partners who will combine advanced modelling tools with the exploitation of experimental data to focus on two major objectives: i) to identify ageing mechanisms when materials face environmental degradation (such as e.g. irradiation and corrosion) and ii) to provide a single platform containing data and tools for reassessment of structural components during NPPs lifetime. This paper provides an overview of the ongoing activities within the SOTERIA Project that are contained within the analytical work-package (WP5.3). These fracture aspects are focused on the estimates of fracture in both ferritic steels and irradiation assisted stress corrosion cracking (IASCC) in austenitic stainless steels, under irradiated conditions. This analytical development is supported by analytical estimates of irradiation damage and the resulting changes in tensile behaviour of the steels elsewhere in SOTERIA, as well as a wider number of experimental programmes. Cleavage fracture estimates are being considered by a range of modelling estimates including the Beremin, Microstructurally Informed Brittle Fracture Model (MIBF), JFJ and Bordet Models with efforts being made to understand the influence of heterogeneity on the predicted toughness’s. Efforts are also being considered to better understand ductile void evolution and the effect of plasticity on the cleavage fracture predictions. IASCC is being modelled through the INITEAC code previously developed within the predecessor project Perform 60 which is being updated to incorporate recent developments from within SOTERIA and elsewhere.

Characteristics of natural neutron radiation background performed within the BSUIN project.

2020 ◽  
Author(s):  
Karol Jedrzejczak ◽  
Marcin Kasztelan ◽  
Jacek Szabelski ◽  
Przemysław Tokarski ◽  
Jerzy Orzechowski ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Background Radiation ◽  
Neutron Radiation ◽  
Radiation Background ◽  
Term Operation ◽  
Baltic Sea Region ◽  
Wide Range ◽  
The Baltic

<p>The BSUIN (Baltic Sea Underground Innovation Network) aims to enhance the accessibility of the underground laboratories in the Baltic Sea region for innovation, business and science. One of the BSUIN project activities is characterization of natural background radiation (NBR) in underground facilities. A specific type of NRB is neutron radiation, whose measurement requires specific instruments and long-term exposure in-situ, in heavy underground conditions.</p><p>In this talk the method of natural neutron radiation background will be presented as well as results of pilot measurements in several underground locations. In order to make this measurements, a measuring setup was designed and made. The setup design is closely matched to the task: the setup is scalable in a wide range, completely remotely controlled (via the Internet) and capable of long-term operation (months).</p><p>The pilot measurements were performed in Callio Lab, Pyhäsalmi, Finland, (4100 m w.e.), in Reiche Zeche mine in Freiberg, Germany (410 m w.e.) and in Experimental Mine “Barbara” in Mikołów, Poland (100 m w.e).</p>

scholarly journals Identifying high performance and durable methylammonium-free lead halide perovskites through high throughput synthesis and characterization

2021 ◽  
Author(s):  
Yu An ◽  
Carlo Andrea Riccardo Perini ◽  
Juanita Hidalgo ◽  
Andrés-Felipe Castro-Méndez ◽  
Vagott Jacob N. ◽  
...  
Keyword(s):  
Solar Cells ◽  
High Performance ◽  
Tolerance Factor ◽  
Structure Property ◽  
Term Operation ◽  
Wide Range ◽  
Holistic Understanding ◽  
Compositional Space ◽  
Tolerance Factors

One of the organic component in the perovskite photo-absorber, the methylammonium cation, has been suggested to be a roadblock to long-term operation of organic-inorganic hybrid perovskite-based solar cells. Methylammonium-free perovskites thus represent a possible direction for more stable photo-absorbers that are also compatible with multijunction solar cells. However, most work on methylammonium-free perovskites involves cesium and formamidinium as the A-site cations, which are thermodynamically less stable than the methylammonium-based materials. In this work we systematically explore the crystallographic and optical properties of the compositional space of mixed cation and mixed halide lead perovskites, where formamidinium (FA+) is gradually replaced by cesium (Cs+), and iodide (I-) is substituted by bromide (Br-), i.e., CsyFA1–yPb(BrxI1–x)3. The crystal phases, which could be tuned by changing the tolerance factor for mixed perovskite alloys, are qualitatively determined and the composition–structure relationship is established in the CsyFA1–yPb(BrxI1–x)3 compositional space. We find that higher tolerance factors lead to more cubic structures, whereas lower tolerance factors lead to more orthorhombic. We also find that while some correlation exists between tolerance factor and structure, tolerance factor does not provide a holistic understanding of whether a perovskite structure will fully form. Given the wide range of bandgaps produced by this compositional space, an empirical expression is devised to predict the optical bandgap of CsyFA1–yPb(BrxI1–x)3 perovskites – which changes as a function of composition –, conducive to the design of absorbers with bandgaps tailor-made for specific tandem and single-junction applications. By screening 26 solar cells with different compositions, we find that Cs1/6FA5/6PbI3 delivers the highest efficiency and long-term stability among I-rich compositions. This work sheds light on the fundamental structure-property relationships in the CsyFA1–yPb(BrxI1–x)3 compositional space, providing vital insight to the design of durable perovskite materials. Our approach provides a library of structural and optoelectronic information of this compositional space.

scholarly journals Motility Profile of Captive-Bred Marmosets Revealed by a Long-Term In-Cage Monitoring System

2021 ◽  
Vol 15 ◽  
Author(s):  
Masashi Koizumi ◽  
Naotake Nogami ◽  
Kensuke Owari ◽  
Akiyo Kawanobe ◽  
Terumi Nakatani ◽  
...  
Keyword(s):  
Age Groups ◽  
Common Marmoset ◽  
New World Monkeys ◽  
Diurnal Activity ◽  
Monitoring Method ◽  
Short Cycle ◽  
Term Operation ◽  
Wide Range ◽  
Term Evaluation

A quantitative evaluation of motility is crucial for studies employing experimental animals. Here, we describe the development of an in-cage motility monitoring method for new world monkeys using off-the-shelf components, and demonstrate its capability for long-term operation (e.g., a year). Based on this novel system, we characterized the motility of the common marmoset over different time scales (seconds, hours, days, and weeks). Monitoring of seven young animals belonging to two different age groups (sub-adult and young-adult) over a 231-day period revealed: (1) strictly diurnal activity (97.3% of movement during daytime), (2) short-cycle (∼20 s) transition in activity, and (3) bimodal diurnal activity including a “siesta” break. Additionally, while the mean duration of short-cycle activity, net daily activity, and diurnal activity changed over the course of development, 24-h periodicity remained constant. Finally, the method allowed for detection of progressive motility deterioration in a transgenic marmoset. Motility measurement offers a convenient way to characterize developmental and pathological changes in animals, as well as an economical and labor-free means for long-term evaluation in a wide range of basic and translational studies.

Removal of pharmaceutically active compounds in nitrifying–denitrifying plants

2005 ◽  
Vol 52 (8) ◽  
pp. 9-14 ◽  
Author(s):  
S. Suárez ◽  
M. Ramil ◽  
F. Omil ◽  
J.M. Lema
Keyword(s):  
Small Extent ◽  
The Other ◽  
Experimental Unit ◽  
Pharmaceutically Active Compounds ◽  
Removal Rates ◽  
Active Compounds ◽  
Term Operation ◽  
Activated Sludge System ◽  
Wide Range

The behaviour of nine pharmaceutically active compounds (PhACs) of different diagnostic groups is studied during a nitrifying–denitrifying process in an activated sludge system. The compounds selected cover a wide range of frequently used substances such as anti-epileptics (carbamazepine), tranquillisers (diazepam), anti-depressants (fluoxetine and citalopram), anti-inflammatories (ibuprofen, naproxen and diclofenac) and estrogens (estradiol and ethinylestradiol). The main objective of this research is to investigate the effect of acclimation of biomass on the removal rates of these compounds, either by maintaining a high sludge retention time or at long-term operation. The removal rates achieved for nitrogen and carbon in the experimental unit exceed 90% and were not affected by the addition of PhACs. Carbamazepine, diazepam and diclofenac were only removed to a small extent. On the other hand, higher removal rates have been observed for naproxen and ibuprofen (68% and 82%), respectively.

scholarly journals Long-term operation of a novel electrically-enhanced biomass concentrator reactor for wastewater treatment

2018 ◽  
Vol 77 (8) ◽  
pp. 2036-2044 ◽  
Author(s):  
D. Cecconet ◽  
A. Callegari ◽  
A. G. Capodaglio
Keyword(s):  
Wastewater Treatment ◽  
Energy Efficient ◽  
Oxygen Demand ◽  
Urban Wastewater ◽  
Term Operation ◽  
Wide Range ◽  
Biomass Retention ◽  
Electrically Enhanced ◽  
Urban Wastewater Treatment

Abstract Membrane biological reactors (MBRs) are a key technology in wastewater treatment nowadays. However, due to their high construction cost and energetic requirements, alternatives based on the same principle of biomass retention have been designed and operated. Amongst these, biomass concentrator reactors (BCRs), using a coarser filter medium instead of a membrane, have shown to be able to remove a wide range of contaminants from wastewater and groundwater. A new BCR-derived technology enhanced with an electric field, called the electrically-enhanced biomass concentrator reactor (E2BCR), was designed and tested for urban wastewater treatment at different organic loads for a period of 180 days. The electrically-enhanced reactor showed better chemical oxygen demand (COD) removal performances than a non-enhanced control reactor (92.4% and 83.6% respectively) thanks also to electrocoagulation effects, and a lower fouling tendency, and proved to be more energy efficient in comparison with the control reactor in terms of energy consumption per mass of COD removed.

scholarly journals Chlorella Vulgaris Photobioreactor for Oxygen and Food Production on a Moon Base—Potential and Challenges

2021 ◽  
Vol 8 ◽  
Author(s):  
Gisela Detrell
Keyword(s):  
Chlorella Vulgaris ◽  
Radiation Effects ◽  
Life Support ◽  
Higher Plants ◽  
Algal Species ◽  
Processing System ◽  
Space Applications ◽  
Operational Conditions ◽  
Wide Range

A base on the Moon surface or a mission to Mars are potential destinations for human spaceflight, according to current space agencies’ plans. These scenarios pose several new challenges, since the environmental and operational conditions of the mission will strongly differ than those on the International Space Station (ISS). One critical parameter will be the increased mission duration and further distance from Earth, requiring a Life Support System (LSS) as independent as possible from Earth’s resources. Current LSS physico-chemical technologies at the ISS can recycle 90% of water and regain 42% of O2 from the astronaut’s exhaled CO2, but they are not able to produce food, which can currently only be achieved using biology. A future LSS will most likely include some of these technologies currently in use, but will also need to include biological components. A potential biological candidate are microalgae, which compared to higher plants, offer a higher harvest index, higher biomass productivity and require less water. Several algal species have already been investigated for space applications in the last decades, being Chlorella vulgaris a promising and widely researched species. C. vulgaris is a spherical single cell organism, with a mean diameter of 6 µm. It can grow in a wide range of pH and temperature levels and CO2 concentrations and it shows a high resistance to cross contamination and to mechanical shear stress, making it an ideal organism for long-term LSS. In order to continuously and efficiently produce the oxygen and food required for the LSS, the microalgae need to grow in a well-controlled and stable environment. Therefore, besides the biological aspects, the design of the cultivation system, the Photobioreactor (PBR), is also crucial. Even if research both on C. vulgaris and in general about PBRs has been carried out for decades, several challenges both in the biological and technological aspects need to be solved, before a PBR can be used as part of the LSS in a Moon base. Those include: radiation effects on algae, operation under partial gravity, selection of the required hardware for cultivation and food processing, system automation and long-term performance and stability.

scholarly journals THE MAIN GAS PIPELINES DEFECTS ANALYZING BY OPERATION PERIOD AND EXTENSION

2019 ◽  
pp. 93-99
Author(s):  
S. V. Kitaev ◽  
N. M. Darsalia ◽  
I. R. Baykov ◽  
O. V. Smorodova
Keyword(s):  
Gini Index ◽  
Gas Pipeline ◽  
Pipeline System ◽  
Gas Pipelines ◽  
Line Pipe ◽  
Term Operation ◽  
Wide Range ◽  
Operation Period ◽  
Standard Service

The gas pipeline system of PJSC «Gazprom» is at the stage of long-term operation. Most of the pipelines exceed the standard service life of 33 years, while considerable resources are required to maintain the trunk gas pipelines in an efficient state. The article analyzes the defectiveness of gas mains by the example of LLC «Gazprom transgaz Ufa». The company’s gas pipeline system consists of a wide range of diameters pipes ranging from DN 400 to DN 1400 mm. Its structure is dominated by pipelines with a diameter of DN 400, 500, 700, 1400 mm, which share exceeds 86 %. An integral Gini index is proposed for monitoring the differentiation of defects along the length of the line pipe of the main gas pipelines. By the value of the proposed indicator, it is possible to analyze and compare the sections of gas pipelines among themselves, to identify the signs that affect the development of defects along the line pipe of the main gas pipelines.

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