2,343 research outputs found
A review of the basic safety requirements of emerging infrastructures for green transition
The transition to a Climate-Neutral economy requires a reduction of energy-related carbon dioxide emissions and Carbon dioxide capture and geological storage (CCS) is a key technology that will contribute to mitigating climate change. Hazards and risks related to processing, transport, and storage of CO2 are not new aspects, but peculiarities of CO2 safety scenarios can lead to risk underestimation and misperception. Solid-phase occurrence and heavy gas dispersion, multiphase releases, leakages from wells and storage sites, and the integrity of equipment subjected to internal corrosion and cryogenic temperatures, are typical scenarios involved in CCS chains. These are often mentioned in technical standards and regulations and require proper advanced assessment. In this work, the main hazards and risk scenarios in CCS operations with a special focus on atypical instances that are peculiar to the case of CO2 will be reviewed. Open issues concerning the modeling of consequences and specific risk-related topics are discussed
Statistical model for intermittent plasma edge turbulence
The Probability Distribution Function of plasma density fluctuations at the
edge of fusion devices is known to be skewed and strongly non-Gaussian. The
causes of this peculiar behaviour are, up to now, largely unexplored. On the
other hand, understanding the origin and the properties of edge turbulence is a
key issue in magnetic fusion research. In this work we show that a stochastic
fragmentation model, already successfully applied to fluid turbulence, is able
to predict an asymmetric distribution that closely matches experimental data.
The asymmetry is found to be a direct consequence of intermittency. A
discussion of our results in terms of recently suggested BHP universal curve
[S.T. Bramwell, P.C.W. Holdsworth, J.-F. Pinton, Nature (London) 396, 552
(1998)], that should hold for strongly correlated and critical systems, is also
proposedComment: 13 pages. Physica Review E, accepte
Identificação e validação de genes de referência para análise de RT-qPCR em arroz.
O objetivo desse estudo foi identificar e validar genes de referência para análise de RTqPCR em arroz.Pôster - pós-graduação
Anotação de genes relacionados à tolerância a seca em arroz (Oryza sativa) de terras altas.
O objetivo deste trabalho foi identificar e anotar os genes expressos em resposta ao déficit hídrico em tecido foliar de duas cultivares brasileiras de arroz de terras altas, a cultivar tolerante à seca Douradão e a cultivar sensível Primavera.Apresentação oral - Pós-graduação
Hybrid Risk-based LCA: An innovative holistic approach to improve the acid gas to syngas (AG2S) process
The sustainable development has recently become the cornerstone of the environmental policy worldwide and a leading principle for resource management. The philosophy lies in a continuous demand of innovative choices able to ensure the existing productive systems survival through a new design paradigm shift. In this regard, the technological innovation should be always driven by the sustainability concept: the economic, societal and environmental impact ought to be continuously fostered to the systems\u2019 sustainable improvement. This demanding goal can be accomplished with a blended Life Cycle (LCA) and Life Risk (LRA) Assessment to highlight the process potential health and environmental impacts. LRA is the process in which imposed risks by the inherent hazards linked to a process are continuously assessed (quantitatively or qualitatively). LCA instead is the process that analyses and assesses the environmental impact of a material, product or service throughout its entire life cycle. LCA and LRA are typically driven by two different approaches, respectively a deterministic and a stochastic approach. This usually drives an unconnected use of LCA and LRA in the quantification of products and processes potential impact and determines controversial decisions with respect to a balance between environmental impacts and operational risks. The new paradigm suggests a unified blended LCA \u2013 LRA approach that is applied at a preliminary stage to an innovative Acid Gas to Syngas (AG2S) process for CO2 emission reduction and on-site reuse, avoiding the costly and hazardous transportation step
About the parabolic relation existing between the skewness and the kurtosis in time series of experimental data
In this work we investigate the origin of the parabolic relation between
skewness and kurtosis often encountered in the analysis of experimental
time-series. We argue that the numerical values of the coefficients of the
curve may provide informations about the specific physics of the system
studied, whereas the analytical curve per se is a fairly general consequence of
a few constraints expected to hold for most systems.Comment: To appear in Physica Script
An improved method for RNA extraction from common bean seeds and validation of reference genes for qPCR.
An RNA extraction method with high integrity and purity as well as the selection of adequate reference genes are prerequisites for gene expression analysis. For common bean seeds, there is no well-defined protocol that can be used in a laboratory routine for gene expression analysis. In this study, an extraction protocol for RNA from common bean seeds, which produced material with good integrity for qPCR (RIN ≥ 6.5), was optimized. In addition, 10 reference genes were evaluated under qPCR standard conditions using different tissue samples of common beans. Gene stabilities were analyzed using the delta-CT method, Bestkeeper, NormFinder and geNorm approaches. The genes β-tubulin and T197 were ranked as the most stable among the sample sets evaluated with different tissue samples, while PvAct and Pv18S were the least stable. To our knowledge, this is the first study evaluating RNA isolation methods and reference gene selection for seeds of Phaseolus vulgaris
In situ remediation of polluted Spolic Technosols using Ca(OH)2 and smectitic marlstone
Technosols are soils developed on non-traditional substrates and containing large quantities of materials mostly due to intensive human industrial activity, such as artefacts. The increasing number of sites affected by Technosols and their impact on the environment as growing media for plants or as source of pollutants require an understanding of their functioning and evolution, above all the knowledge on the transport of toxic substances from contaminated technogenic soils to groundwater. A case study on properties, remediation and evaluation of Technosols made up by vitrified fly ash and glass\u2013ceramics in Italy was carried out. Original technogenic soils, classified as Spolic Technosols (ecotoxic),were pedotechnically in situ remediated by adding smectitic marlstone and Ca(OH)2. Chemical analysis on samples from piezometers showed the presence of harmful heavy metals in groundwater. By means of boreholes and soil profiles the newsoils generated, after remediation, were physically and chemically characterized and classified as Spolic Technosols (calcaric). Analysis on soil toxicity and leaching tests showed the effectiveness of the remediation and the mobility reduction of some potentially harmful elements according to the environmental Italian regulation
Transient Analysis of Warm Electron Injection Programming of Double Gate SONOS Memories by means of Full Band Monte Carlo Simulation
In this paper we investigate "Warm Electron Injection" as a mechanism for NOR
programming of double-gate SONOS memories through 2D full band Monte Carlo
simulations. Warm electron injection is characterized by an applied VDS smaller
than 3.15 V, so that electrons cannot easily accumulate a kinetic energy larger
than the height of the Si/SiO2 barrier. We perform a time-dependent simulation
of the program operation where the local gate current density is computed with
a continuum-based method and is adiabatically separated from the 2D full Monte
Carlo simulation used for obtaining the electron distribution in the phase
space. In this way we are able to compute the time evolution of the charge
stored in the nitride and of the threshold voltages corresponding to forward
and reverse bias. We show that warm electron injection is a viable option for
NOR programming in order to reduce power supply, preserve reliability and CMOS
logic level compatibility. In addition, it provides a well localized charge,
offering interesting perspectives for multi-level and dual bit operation, even
in devices with negligible short channel effects
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