Experimental determination of mass-transfer coefficients and area of dumped packing using alkanolamine solvents

AbstractThe absorption process is strongly influenced by the effective contact area. In absorber columns, this is related to the type of the internals used in the columns. Therefore, a good representation of the effective mass-transfer area and mass-transfer coefficients (kL or kg) is also essential for accurately represent and design a process. For CO2 capture process packed columns are usually preferred. The mass transfer area and coefficients for several packing (both structured and random) are correlated elsewhere. In this work mass transfer experiments using concentrated MEA solution in the Procede acid gas treating pilot plant are performed. However, due to the fast reaction between MEA and CO2, both the gas side and liquid side mass transfer resistances are relevant and the mass transfer area cannot be determined experimentally. Nevertheless, the volumetric mass transfer coefficient is calculated and it showed to be relatively constant for all the runs. The results from the pilot plant are compared to simulated results using Procede Process Simulator (PPS). The mass transfer area and mass transfer coefficients were calculated through the default correlations implemented in PPS. Very good agreement is achieved between the experimental and simulated results

Niñez e interpretación ambiental en el proyecto jardín botánico de la Universidad del Cauca Álvaro José Negret (UCAJN)

La evaluación cualitativa mediante la técnica de mapas conceptuales, realizada en el espacio Jardín Botánico-UCAJN con un grupo de niños de cuarto y quinto grado de las instituciones educativas: Comercial del Norte Francisco José Chaux Ferrer (CNFJCF) de la vereda La Rejoya y Rafael Pombo (RP) de la ciudad de Popayán a través de tres fases consecutivas (exploración, validación y aplicación), permitió evidenciar un aprendizaje significativo ascendente, reflejado en la asimilación progresiva de conceptos, tanto en la estructuración de los mapas conceptuales como en la adquisición de valores ético-ambientales (estético, ecológico, económico, humanístico, moral, recreativo y científico) hacia el entorno. A lo largo de la investigación, esta progresión condujo a estructurar una charla modelo de interpretación ambiental para niños en edad escolar y a soportar posteriormente el plan de interpretación ambiental para el proyecto de Jardín Botánico-UCAJN. ABSTRACTThe qualitative evaluation by means of the conceptual maps technique carried out in the UCAJN botanical garden space with a group of fourth and fifth grade children from the educational institutions North Commercial Chaux Francisco José Ferrer (CNFJCF) of La Rejoya and Rafael Pombo (RP) in the city of Popayán through three consecutive phases (exploration, validation and  mplementation), allowed to demonstrate an increasingly significant learning process reflected in the gradual assimilation of concepts, both in the structure of conceptual maps and the acquisition of ethical and environmental values (aesthetic, ecological, economic, humanistic, moral, recreational, and scientific) towards the environment. Throughout the investigation, this progression led to the structure of an environmental interpretation talk model for school children and then to support the environmental interpretation plan for the UCAJN Botanical Garden project. La evaluación cualitativa mediante la técnica de mapas conceptuales, realizada en el espacio Jardín Botánico-UCAJN con un grupo de niños de cuarto y quinto grado de las instituciones educativas: Comercial del Norte Francisco José Chaux Ferrer (CNFJCF) de la vereda La Rejoya y Rafael Pombo (RP) de la ciudad de Popayán a través de tres fases consecutivas (exploración, validación y aplicación), permitió evidenciar un aprendizaje significativo ascendente, reflejado en la asimilación progresiva de conceptos, tanto en la estructuración de los mapas conceptuales como en la adquisición de valores ético-ambientales (estético, ecológico, económico, humanístico, moral, recreativo y científico) hacia el entorno. A lo largo de la investigación, esta progresión condujo a estructurar una charla modelo de interpretación ambiental para niños en edad escolar y a soportar posteriormente el plan de interpretación ambiental para el proyecto de Jardín Botánico-UCAJN. ABSTRACTThe qualitative evaluation by means of the conceptual maps technique carried out in the UCAJN botanical garden space with a group of fourth and fifth grade children from the educational institutions North Commercial Chaux Francisco José Ferrer (CNFJCF) of La Rejoya and Rafael Pombo (RP) in the city of Popayán through three consecutive phases (exploration, validation and  mplementation), allowed to demonstrate an increasingly significant learning process reflected in the gradual assimilation of concepts, both in the structure of conceptual maps and the acquisition of ethical and environmental values (aesthetic, ecological, economic, humanistic, moral, recreational, and scientific) towards the environment. Throughout the investigation, this progression led to the structure of an environmental interpretation talk model for school children and then to support the environmental interpretation plan for the UCAJN Botanical Garden project.

The nonlinearity of pupil diameter fluctuations in an insight task as criteria for detecting children who solve the problem from those who do not

Insights, characterized by sudden discoveries following unsuccessful problem-solving attempts, are fascinating phenomena. Dynamic systems perspectives argue that insight arises from self-organizing perceptual and motor processes. Entropy and fractal scaling are potential markers for emerging new and effective solutions. This study investigated whether specific features associated with self-organization in dynamical systems can distinguish between individuals who succeed and those who fail in solving insight tasks. To achieve this, we analyzed pupillary diameter fluctuations of children aged 6 to 12 during the 8-coin task, a well-established insight task. The participants were divided into two groups: successful (n = 24) and unsuccessful (n = 43) task completion. Entropy, determinism, recurrence ratio, and the β scaling exponent were estimated using Recurrence Quantification and Power Spectrum Density analyses. The results indicated that the solver group exhibited more significant uncertainty and lower predictability in pupillary diameter fluctuations before finding the solution. Recurrence Quantification Analysis revealed changes that went unnoticed by mean and standard deviation measures. However, the β scaling exponent did not differentiate between the two groups. These findings suggest that entropy and determinism in pupillary diameter fluctuations can identify early differences in problem-solving success. Further research is needed to determine the exclusive role of perceptual and motor activity in generating insights and investigate these results’ generalizability to other tasks and populations

Relevance of hazards in exoskeleton applications: a survey-based enquiry

Exoskeletons are becoming the reference technology for assistance and augmentation of human motor functions in a wide range of application domains. Unfortunately, the exponential growth of this sector has not been accompanied by a rigorous risk assessment (RA) process, which is necessary to identify the major aspects concerning the safety and impact of this new technology on humans. This situation may seriously hamper the market uptake of new products. This paper presents the results of a survey that was circulated to understand how hazards are considered by exoskeleton users, from research and industry perspectives. Our analysis aimed to identify the perceived occurrence and the impact of a sample of generic hazards, as well as to collect suggestions and general opinions from the respondents that can serve as a reference for more targeted RA. Our results identified a list of relevant hazards for exoskeletons. Among them, misalignments and unintended device motion were perceived as key aspects for exoskeletons’ safety. This survey aims to represent a first attempt in recording overall feedback from the community and contribute to future RAs and the identification of better mitigation strategies in the field.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. The work presented was developed within the project EXOSAFE and SALOEXO, an awarded project by the COVR European Project under grant agreement No 779966

Adiabatic and entropy perturbations propagation in a bouncing Universe

By studying some bouncing universe models dominated by a specific class of hydrodynamical fluids, we show that the primordial cosmological perturbations may propagate smoothly through a general relativistic bounce. We also find that the purely adiabatic modes, although almost always fruitfully investigated in all other contexts in cosmology, are meaningless in the bounce or null energy condition (NEC) violation cases since the entropy modes can never be neglected in these situations: the adiabatic modes exhibit a fake divergence that is compensated in the total Bardeen gravitational potential by inclusion of the entropy perturbations.Comment: 25 pages, no figure, LaTe

Making Bipedal Robot Experiments Reproducible and Comparable: The Eurobench Software Approach

This study describes the software methodology designed for systematic benchmarking of bipedal systems through the computation of performance indicators from data collected during an experimentation stage. Under the umbrella of the European project Eurobench, we collected approximately 30 protocols with related testbeds and scoring algorithms, aiming at characterizing the performances of humanoids, exoskeletons, and/or prosthesis under different conditions. The main challenge addressed in this study concerns the standardization of the scoring process to permit a systematic benchmark of the experiments. The complexity of this process is mainly due to the lack of consistency in how to store and organize experimental data, how to define the input and output of benchmarking algorithms, and how to implement these algorithms. We propose a simple but efficient methodology for preparing scoring algorithms, to ensure reproducibility and replicability of results. This methodology mainly constrains the interface of the software and enables the engineer to develop his/her metric in his/her favorite language. Continuous integration and deployment tools are then used to verify the replicability of the software and to generate an executable instance independent of the language through dockerization. This article presents this methodology and points at all the metrics and documentation repositories designed with this policy in Eurobench. Applying this approach to other protocols and metrics would ease the reproduction, replication, and comparison of experiments.This study is supported by the European Union’s Horizon 2020 research and innovation program under Grant Agreement no 779963, project Eurobench

Epsilon Indi Ba, Bb: a detailed study of the nearest known brown dwarfs

The discovery of epsilon Indi Ba, Bb, a binary brown dwarf system very close to the Sun, makes possible a concerted campaign to characterise the physical parameters of two T dwarfs. Recent observations suggest substellar atmospheric and evolutionary models may be inconsistent with observations, but there have been few conclusive tests to date. We therefore aim to characterise these benchmark brown dwarfs to place constraints on such models. We have obtained high angular resolution optical, near-infrared, and thermal-infrared imaging and medium-resolution (up to R~5000) spectroscopy of epsilon Indi Ba, Bb with the ESO VLT and present VRIzJHKL'M' broad-band photometry and 0.63--5.1 micron spectroscopy of the individual components. Furthermore, we use deep AO-imaging to place upper limits on the (model-dependent) mass of any further system members. We derive luminosities of log L/L_sun = -4.699+/-0.017 and -5.232+/-0.020 for epsilon Indi Ba, Bb, respectively, and using the dynamical system mass and COND03 evolutionary models predict a system age of 3.7--4.3 Gyr, in excess of previous estimates and recent predictions from observations of these brown dwarfs. Moreover, the effective temperatures of 1352--1385 K and 976--1011 K predicted from the COND03 evolutionary models, for epsilon Indi Ba and Bb respectively, are in disagreement with those derived from the comparison of our data with the BT-Settl atmospheric models where we find effective temperatures of 1300--1340 K and 880--940 K, for epsilon Indi Ba and Bb respectively, with surface gravities of log g=5.25 and 5.50. Finally, we show that spectroscopically determined effective temperatures and surface gravities for ultra-cool dwarfs can lead to underestimated masses even where precise luminosity constraints are available.Comment: 27 pages, 30 figures, 9 tables, accepted for publication in Astronomy and Astrophysic

World Heart Federation consensus on transthyretin amyloidosis cardiomyopathy (ATTR-CM)

COPYRIGHT: © 2023 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/ licenses/by/4.0/.Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive and fatal condition that requires early diagnosis, management, and specific treatment. The availability of new disease-modifying therapies has made successful treatment a reality. Transthyretin amyloid cardiomyopathy can be either age-related (wild-type form) or caused by mutations in the TTR gene (genetic, hereditary forms). It is a systemic disease, and while the genetic forms may exhibit a variety of symptoms, a predominant cardiac phenotype is often present. This document aims to provide an overview of ATTR-CM amyloidosis focusing on cardiac involvement, which is the most critical factor for prognosis. It will discuss the available tools for early diagnosis and patient management, given that specific treatments are more effective in the early stages of the disease, and will highlight the importance of a multidisciplinary approach and of specialized amyloidosis centres. To accomplish these goals, the World Heart Federation assembled a panel of 18 expert clinicians specialized in TTR amyloidosis from 13 countries, along with a representative from the Amyloidosis Alliance, a patient advocacy group. This document is based on a review of published literature, expert opinions, registries data, patients' perspectives, treatment options, and ongoing developments, as well as the progress made possible via the existence of centres of excellence. From the patients' perspective, increasing disease awareness is crucial to achieving an early and accurate diagnosis. Patients also seek to receive care at specialized amyloidosis centres and be fully informed about their treatment and prognosis.info:eu-repo/semantics/publishedVersio

World Heart Federation Consensus on Transthyretin Amyloidosis Cardiomyopathy (ATTR-CM)

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive and fatal condition that requires early diagnosis, management, and specific treatment. The availability of new disease-modifying therapies has made successful treatment a reality. Transthyretin amyloid cardiomyopathy can be either age-related (wild-type form) or caused by mutations in the TTR gene (genetic, hereditary forms). It is a systemic disease, and while the genetic forms may exhibit a variety of symptoms, a predominant cardiac phenotype is often present. This document aims to provide an overview of ATTR-CM amyloidosis focusing on cardiac involvement, which is the most critical factor for prognosis. It will discuss the available tools for early diagnosis and patient management, given that specific treatments are more effective in the early stages of the disease, and will highlight the importance of a multidisciplinary approach and of specialized amyloidosis centres. To accomplish these goals, the World Heart Federation assembled a panel of 18 expert clinicians specialized in TTR amyloidosis from 13 countries, along with a representative from the Amyloidosis Alliance, a patient advocacy group. This document is based on a review of published literature, expert opinions, registries data, patients’ perspectives, treatment options, and ongoing developments, as well as the progress made possible via the existence of centres of excellence. From the patients’ perspective, increasing disease awareness is crucial to achieving an early and accurate diagnosis. Patients also seek to receive care at specialized amyloidosis centres and be fully informed about their treatment and prognosis