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1.
ACS Omega ; 9(10): 12184-12194, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38496975

RESUMO

The catalytic activity of bimetallic catalysts for the steam methane reforming (SMR) reaction was extensively studied previously. However, the performance of these materials in the presence of sulfur-containing species is yet to be investigated. In this study, we propose a novel process aided by machine learning (ML) and microkinetic modeling for the rapid screening of sulfur-resistant bimetallic catalysts. First, various ML models were developed to predict atomic adsorption energies (C, H, O, and S) on bimetallic surfaces. Easily accessible physical and chemical properties of the metals and adsorbates were used as input features. The Ensemble learning, artificial neural network, and support vector regression models achieved the best performance with R2 values of 0.74, 0.71, and 0.70, respectively. A microkinetic model was then built based on the elementary steps of the SMR reaction. Finally, the microkinetic model, together with the atomic adsorption energies predicted by the Ensemble model, were used to screen over 500 bimetallic materials. Four Ge-based alloys (Ge3Cu1, Ge3Ni1, Ge3Co1, and Ge3Fe1) and the Ni3Cu1 alloy were identified as promising and cost-effective sulfur-resistant catalysts.

2.
Behav Sci (Basel) ; 13(9)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37753991

RESUMO

Combat sports require participants to engage in potentially dangerous forms of contact-based competition. Pressure to succeed, coupled with the risk of severe injury can induce significant levels of anxiety, which if uncontrolled, can negatively impact performance and possibly promote unsporting conduct. The present study examined competitive anxiety levels of combat sports athletes and determined whether self-reported scores were associated with mental toughness and Sportspersonship attitudes. A cross-sectional survey design was used whereby participants (N = 194) completed a battery of questionnaires measuring competitive combat sport experiences, demographic details, Sportspersonship traits (compliance towards rules, respect for opponents, and game perspective), and competition anxiety (somatic, cognitive, and self-confidence; reported retrospectively). Results suggest that mentally tough athletes experience lower levels of cognitive and somatic anxiety, and higher self-confidence, prior to competitions. Findings also found that athletes endorsing more altruistic and respectful attitudes in sport (Sportspersonship) reported higher levels of competition anxiety. The findings demonstrate that mental toughness is allied to positive attributes and could potentially be operationalized to improve both the retention and performance of combat sports athletes. Thus, the authors advocate the use of mental toughness coaching interventions within combat sports.

3.
J Environ Manage ; 323: 116211, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113294

RESUMO

The deployment of greenhouse gas removal (GGR) technologies has been identified as an indispensable option in limiting global warming to 1.5 °C by the end of the century. Despite this, many countries are yet to include and promote this option in their long-term plans owing to factors such as uncertainty in technical potential, deployment feasibility and economic impact. This work presents a country-level assessment of the deployment potential of five GGR technologies, including forestation, enhanced weathering (EW), direct air carbon capture and storage (DACCS), bioenergy with carbon capture and storage (BECCS) and biochar. Using a multi criteria decision analysis (MCDA) approach consisting of bio-geophysical and techno-economic factors, priority regions for the deployment of these GGR technologies were identified. The extent of carbon dioxide removable by 2100 via these technologies was also estimated for each of the 182 countries considered. While the obtained results indicate the need for regional cooperation among countries, it also provides useful evidence on the need for countries to include and prioritise GGR technologies in their revised nationally determined contributions (NDCs).


Assuntos
Gases de Efeito Estufa , Dióxido de Carbono/análise , Aquecimento Global , Gases de Efeito Estufa/análise , Tempo (Meteorologia)
4.
Ind Eng Chem Res ; 61(26): 9218-9233, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35818477

RESUMO

The process of sorption enhanced steam methane reforming (SE-SMR) is an emerging technology for the production of low carbon hydrogen. The development of a suitable catalytic material, as well as a CO2 adsorbent with high capture capacity, has slowed the upscaling of this process to date. In this study, to aid the development of a combined sorbent catalyst material (CSCM) for SE-SMR, a novel approach involving quantitative structure-property relationship analysis (QSPR) has been proposed. Through data-mining, two databases have been developed for the prediction of the last cycle capacity (gCO2 /gsorbent) and methane conversion (%). Multitask learning (MTL) was applied for the prediction of CSCM properties. Patterns in the data of this study have also yielded further insights; colored scatter plots were able to show certain patterns in the input data, as well as suggestions on how to develop an optimal material. With the results from the actual vs predicted plots collated, raw materials and synthesis conditions were proposed that could lead to the development of a CSCM that has good performance with respect to both the last cycle capacity and the methane conversion.

5.
Front Psychol ; 12: 654836, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34366972

RESUMO

Currently there is debate as to whether mental toughness is a unidimensional or multidimensional construct. To investigate the dimensionality of the Mental Toughness Questionnaire 48-items (MTQ48), a widely used measure of mental toughness, we examined data from a sample of 78,947 participants. A series of exploratory structural equation models (ESEM) assessed unidimensional, multidimensional, and bifactor solutions. Overall, results supported a bifactor conceptualization of mental toughness. Bifactor analysis was consistent with the use of a general factor score. In conclusion, the authors argue that mental toughness should be considered as an umbrella term representing a general trait comprised of related constructs that provide a psychological advantage in performance and promote positive mental health. Finally, this article identifies limitations in the existing measurement of mental toughness and proposes necessary directions in future research.

6.
J Environ Manage ; 294: 113039, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34153633

RESUMO

In this study, a comparative literature-based assessment of the impact of operational factors such as climatic condition, vegetation type, availability of land, water, energy and biomass, management practices, cost and soil characteristics was carried out on six greenhouse gas removal (GGR) methods. These methods which include forestation, enhanced weathering (EW), soil carbon sequestration (SCS), biochar, direct air capture with carbon storage (DACCS) and bioenergy with carbon capture and storage (BECCS) were accessed with the aim of identifying the conditions and requirements necessary for their optimum performance. The extent of influence of these factors on the performance of the various GGR methods was discussed and quantified on a scale of 0-5. The key conditions necessary for optimum performance were identified with forestation, EW, SCS and biochar found to be best deployed within the tropical and temperate climatic zones. The CCS technologies (BECCS and DACCS) which have been largely projected as major contributors to the attainment of the emission mitigation targets were found to have a larger locational flexibility. However, the need for cost optimal siting of the CCS plant is necessary and dependent on the presence of appropriate storage facilities, preferably geological. The need for global and regional cooperation as well as some current efforts at accelerating the development and deployment of these GGR methods were also highlighted.


Assuntos
Gases de Efeito Estufa , Biomassa , Carbono , Dióxido de Carbono/análise , Sequestro de Carbono , Gases de Efeito Estufa/análise , Solo
8.
J Hazard Mater ; 404(Pt B): 124045, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33053465

RESUMO

The pollution of semi-volatile heavy metals is one of the key environmental risks for municipal solid waste incineration, and in-situ adsorption of metals within the furnace by mineral sorbents such as kaolin has been demonstrated as a promising emission control method. To lessen the consumption of sorbent, a novel material of amorphous silicate was produced from kaolin through pressurised hydrothermal treatment. Its performance of gaseous PbCl2 capture was tested in a fixed bed furnace and compared with unmodified kaolin and metakaolin. With increasing temperature, the adsorption rates for all sorbents declined due to higher saturated vapour pressure, while the partitions of residual form lead increased which indicated higher stability of heavy metals in the sorbent because of melting effect. The new sorbent with a larger surface area and reformed structure presented 26% more adsorption efficiency than raw kaolin at 900 °C, and increasing the modification pressure improved these properties. Additionally, the production of this high-temperature sorbent was relatively inexpensive, required little thermal energy and no chemicals to produce and no waste effluent was generated, thus being much cleaner than other modification methods.

9.
Front Psychiatry ; 11: 607246, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33613333

RESUMO

Concerns toward public well-being and mental health are increasing considering the COVID-19 pandemic's global societal and individual impact. The present study builds on the current body of COVID-19 literature by examining the role of mental toughness (MT) in predicting negative affective states (depression, anxiety and stress) during the pandemic. The study also examined the effects of changes in employment on mental health and MT. Participants (N = 723) completed a battery of questionnaires including the Mental Toughness Questionnaire 48-item, The State-Trait Anxiety Inventory, and the Depression, Anxiety and Stress Scale - 21 items. Participants reported relatively higher levels of depression, stress and anxiety in comparison to pre-COVID-19 samples from previous research, with respondents who had lost their jobs during the pandemic reporting higher levels of negative affective states. Despite this, mentally tough individuals appeared to report lower levels of depression, anxiety and stress. Moreover, moderation analyses identified some interaction between MT and employment status when predicting depression, anxiety and stress. Our findings suggest that MT may have some utility in reducing the adverse mental health effects of the pandemic on individuals, however, further longitudinal research is needed to support these implications.

10.
Front Psychol ; 10: 1933, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496983

RESUMO

The 18-item Mental Toughness Questionnaire (MTQ-18) is a brief, widely used measure of mental toughness. The MTQ-18 derives from the longer MTQ-48, which comprises four independent but correlated factors (challenge, commitment, control, and confidence). Despite sampling items from across MTQ-48 dimensions, the MTQ-18 (as intended) provides a global, unidimensional score. Researchers have recently developed a further abridged version of the MTQ-18, the MTQ-10, which has demonstrated promising psychometric performance. The current paper assessed the factorial structure, reliability, predictive validity and invariance of the MTQ-18 and MTQ-10 in a sample of 944 students from English independent schools (year 11, aged 16 years). Respondents completed the MTQ-18 items online alongside the Satisfaction with Life Scale. Confirmatory factor analysis revealed that the MTQ-10 was a superior general measure, because the MTQ-18 possessed additional variance to that accounted for by an unidimensional solution. Additionally, the MTQ-10 evidenced higher factor loadings and demonstrated better data-model fit. Tests of concurrent validity revealed the MTQ-10 was a stronger predictor of well-being (life satisfaction). Both the MTQ-18 and MTQ-10 demonstrated gender invariance at the configural, metric, and scalar level. Overall, although the MTQ-18 was a psychometrically acceptable measure, the MTQ-10 was a superior unidimensional measure of MT.

11.
J Pers ; 87(6): 1250-1263, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30854652

RESUMO

OBJECTIVE: We employed the network methodology to explore the connections between the Dark Triad (DT) traits with Mental Toughness (MT) and the degree to which they account for perceived stress beyond the Big Five (B5). METHOD: Network analyses were undertaken to explore connections between the DT, MT, and perceived stress, independently in two samples, and in the combined dataset; and whether B5 factors are responsible for the connections that emerged in the original network. RESULTS: DT and MT traits improved the prediction of perceived stress above the B5. Furthermore, narcissism occupied a strategic position in the network acting as a bridge between prosocial and "dark" sides of personality. The pattern of network connections could not be explained by B5 traits alone. CONCLUSIONS: The results suggest that there is more to personality than what can be captured by the B5 and that broadening the domain of personality beyond the B5 can improve the prediction of important outcomes, such as perceived stress. Narcissism is a unique trait and studying its connection with MT may be the key to moving forward from a dichotomous way of perceiving personality traits, as beneficial or malevolent, to focusing on a dynamic continuum of personality.


Assuntos
Transtorno da Personalidade Antissocial/fisiopatologia , Narcisismo , Personalidade/fisiologia , Resiliência Psicológica , Estresse Psicológico/fisiopatologia , Adulto , Feminino , Humanos , Maquiavelismo , Masculino
12.
Materials (Basel) ; 11(5)2018 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-29883427

RESUMO

The performance of combined CO2-sorbent/catalyst particles for sorption enhanced steam reforming (SESR), prepared via a simple mechanical mixing protocol, was studied using a spout-fluidised bed reactor capable of continuous solid fuel (biomass) feeding. The influence of particle size (300⁻500 and 710⁻1000 µm), CaO loading (60⁻100 wt %), Ni-loading (10⁻40 wt %) and presence of dicalcium silicate support (22.6 wt %) on SESR process performance were investigated. The combined particles were characterised by their density, porosity and CO2 carrying capacity with the analysis by thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH) and mercury intrusion porosimetry (MIP). All experiments were conducted with continuous oak biomass feeding at a rate of 0.9 g/min ± 10%, and the reactor was operated at 660 ± 5 °C, 1 atm and 20 ± 2 vol % steam which corresponds to a steam-to-carbon ratio of 1.2:1. Unsupported combined particles containing 21.0 wt % Ni and 79 wt % CaO were the best performing sorbent/catalyst particle screened in this study, when accounting for the cost of Ni and the improvement in H2 produced by high Ni content particles. SESR tests with these combined particles produced 61 mmol H2/gbiomass (122 g H2/kgbiomass) at a purity of 61 vol %. Significant coke formation within the feeding tube and on the surfaces of the particles was observed which was attributed to the low steam to carbon ratio utilised.

13.
Front Psychol ; 8: 1721, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29062288

RESUMO

The present study assessed the degree to which probabilistic reasoning performance and thinking style influenced perception of risk and self-reported levels of terrorism-related behavior change. A sample of 263 respondents, recruited via convenience sampling, completed a series of measures comprising probabilistic reasoning tasks (perception of randomness, base rate, probability, and conjunction fallacy), the Reality Testing subscale of the Inventory of Personality Organization (IPO-RT), the Domain-Specific Risk-Taking Scale, and a terrorism-related behavior change scale. Structural equation modeling examined three progressive models. Firstly, the Independence Model assumed that probabilistic reasoning, perception of risk and reality testing independently predicted terrorism-related behavior change. Secondly, the Mediation Model supposed that probabilistic reasoning and reality testing correlated, and indirectly predicted terrorism-related behavior change through perception of risk. Lastly, the Dual-Influence Model proposed that probabilistic reasoning indirectly predicted terrorism-related behavior change via perception of risk, independent of reality testing. Results indicated that performance on probabilistic reasoning tasks most strongly predicted perception of risk, and preference for an intuitive thinking style (measured by the IPO-RT) best explained terrorism-related behavior change. The combination of perception of risk with probabilistic reasoning ability in the Dual-Influence Model enhanced the predictive power of the analytical-rational route, with conjunction fallacy having a significant indirect effect on terrorism-related behavior change via perception of risk. The Dual-Influence Model possessed superior fit and reported similar predictive relations between intuitive-experiential and analytical-rational routes and terrorism-related behavior change. The discussion critically examines these findings in relation to dual-processing frameworks. This includes considering the limitations of current operationalisations and recommendations for future research that align outcomes and subsequent work more closely to specific dual-process models.

14.
Res Sports Med ; 25(4): 480-494, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28825346

RESUMO

Fifty-nine men completed a VO2max test and a questionnaire to establish reasons for test termination, perceived exercise reserve (difference between actual test duration and the duration the individual perceived could have been achieved if continued until physical limitation), and perception of verbal encouragement. Participants gave between 1 and 11 factors as reasons for test termination, including leg fatigue, various perceptions of physical discomfort, safety concerns, and achievement of spontaneously set goals. The two most common main reasons were leg fatigue and breathing discomfort, which were predicted by pre-to-post test changes in pulmonary function (p = 0.038) and explosive leg strength (p = 0.042; R2 = 0.40). Median (interquartile range) perceived exercise reserve, was 45 (50) s. Two-thirds of participants viewed verbal encouragement positively, whereas one-third had a neutral or negative perception. This study highlights the complexity of exercise tolerance during VO2max testing and more research should explore these novel findings.


Assuntos
Tolerância ao Exercício , Exercício Físico/fisiologia , Exercício Físico/psicologia , Consumo de Oxigênio , Esforço Físico , Adulto , Teste de Esforço , Humanos , Masculino , Cooperação do Paciente/psicologia , Inquéritos e Questionários , Adulto Jovem
15.
Front Psychol ; 8: 1345, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848466

RESUMO

Mental toughness (MT) is an umbrella term that entails positive psychological resources, which are crucial across a wide range of achievement contexts and in the domain of mental health. We systematically review empirical studies that explored the associations between the concept of MT and individual differences in learning, educational and work performance, psychological well-being, personality, and other psychological attributes. Studies that explored the genetic and environmental contributions to individual differences in MT are also reviewed. The findings suggest that MT is associated with various positive psychological traits, more efficient coping strategies and positive outcomes in education and mental health. Approximately 50% of the variation in MT can be accounted for by genetic factors. Furthermore, the associations between MT and psychological traits can be explained mainly by either common genetic or non-shared environmental factors. Taken together, our findings suggest a 'mental toughness advantage' with possible implications for developing interventions to facilitate achievement in a variety of settings.

16.
Front Psychol ; 8: 1058, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28694788

RESUMO

Research from a variety of scientific fields suggests that physical activity in nature and feelings of connection to nature enhance psychological health and well-being. This study investigated the psychological health and well-being impact of the physical activity environment for those already undertaking the recommended weekly amount of physical activity. This topic is important for the design of health and well-being environments and interventions involving physical activity. Participants (N = 262) aged 18-71 years (M = 34.5, SD = 13.1) who met the UK physical activity guidelines completed the Nature Relatedness Scale, the trait section of the State Trait Inventory for Cognitive and Somatic Anxiety and the Psychological Well-Being Scale. Analysis via Multivariate ANOVA indicated that participants who engaged in outdoor physical activity reported significantly lower somatic anxiety levels and higher Nature Relatedness experience (NRexp). Significant results were not evident for wellbeing. Hierarchical regressions revealed that the psychological well-being facet of autonomy, NRexp, and outdoor physical activity predicted lower somatic anxiety, whereas indoor physical activity predicted higher somatic anxiety. Results indicate that somatic anxiety is lower for outdoor physical activity participation, and that outdoor activity, in conjunction with autonomy and NRexp, predicts lower anxiety levels. The findings extend previous work by demonstrating the impact of the physical activity environment on anxiety levels, as well as the contribution of outdoor physical activity and well-being facets to the previously established Nature Relatedness-anxiety relationship.

17.
Front Psychol ; 8: 942, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28642726

RESUMO

Recent research suggests that unconventional beliefs are locatable within a generic anomalous belief category. This notion derives from the observation that apparently dissimilar beliefs share fundamental, core characteristics (i.e., contradiction of orthodox scientific understanding of the universe and defiance of conventional understanding of reality). The present paper assessed the supposition that anomalous beliefs were conceptually similar and explicable via common psychological processes by comparing relationships between discrete beliefs [endorsement of urban legends (ULs) and belief in the paranormal] and cognitive-perceptual personality measures [proneness to reality testing (RT) and schizotypy]. A sample of 222 volunteers, recruited via convenience sampling, took part in the study. Participants completed a series of self-report measures (Urban Legends Questionnaire, Reality Testing subscale of the Inventory of Personality Organization, Revised Paranormal Belief Scale and the Schizotypal Personality Questionnaire Brief). Preliminary analysis revealed positive correlations between measures. Within schizotypy, the cognitive-perceptual factor was most strongly associated with anomalistic beliefs; disorganized and interpersonal produced only weak and negligible correlations respectively. Further investigation indicated complex relationships between RT, the cognitive-perceptual factor of schizotypy and anomalistic beliefs. Specifically, proneness to RT deficits explained a greater amount of variance in ULs, whilst schizotypy accounted for more variance in belief in the paranormal. Consideration of partial correlations supported these conclusions. The relationship between RT and ULs remained significant after controlling for the cognitive-perceptual factor. Contrastingly, the association between the cognitive-perceptual factor and ULs controlling for RT was non-significant. In the case of belief in the paranormal, controlling for proneness to RT reduced correlation size, but relationships remained significant. This study demonstrated that anomalistic beliefs vary in nature and composition. Findings indicated that generalized views of anomalistic beliefs provide only limited insight into the complex nature of belief.

18.
Psychol Rep ; 120(2): 271-289, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28558619

RESUMO

Young people are particularly vulnerable to health risk behaviors and interpersonal violence, stimulating scholars' attention towards identifying factors that may reduce the likelihood that these actions will occur. Associated with positive outcomes in a variety of domains, mental toughness in young people might protect them from engaging in potentially deleterious interpersonal or health-risk behaviors, while potentially promoting positive psychological behaviors. Within this framework, the present study investigated the relationships between mental toughness, attitudes towards physical and psychological risk-taking, and trait forgiveness in a sample of 123 (males = 54, females = 69) South African youth ( M age = 23.97 years, SD = 4.46). Univariate and multivariate analyses indicated higher levels of mental toughness were associated with being more forgiving, ([Formula: see text] = .036), perceiving physical risk-taking more positively ([Formula: see text] = .062), but having more negative attitudes towards psychological risk-taking ([Formula: see text] = .036). These findings give credence to mental toughness as a psychological characteristic involved in youth risk-taking perceptions and interpersonal functioning. Future research might explore the integration of mental toughness into the development of future youth risk behavior interventions.


Assuntos
Atitude , Personalidade , Resiliência Psicológica , Assunção de Riscos , Adolescente , Adulto , Feminino , Perdão , Humanos , Relações Interpessoais , Masculino , África do Sul , Adulto Jovem
19.
J Sports Sci ; 35(5): 426-434, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27033183

RESUMO

Numerous studies showed that regular physical activity (PA) is associated with both favourable and restorative sleep and improved psychological functioning (PF). However, there is little research on the topic covering the early to mid-adolescence period. Moreover, curiosity and exploratory behaviour (CEB) and mental toughness (MT) as a result of PA remains thus far uninvestigated, as do possible gender differences. The aim of the present study was to explore the associations between PA, subjective sleep (sS), PF, CEB, and MT during early to mid-adolescence. A total of 1361 participants (mean age = 13.37 years; range: 11-16 years; 51.2% female) took part in the study. They completed questionnaires covering PA, sS, PF, CEB, and MT. Greater PA was related to improved PF, better sS, and increased CEB and MT. Compared to male participants, females reported less PA, poorer sS, and had lower PF and MT scores. The present pattern of results suggests that during early and mid-adolescence greater PA was associated with more favourable sS and better PF, including CEB and MT, and that female participants reported lower scores in PA, sS, and PF. Accordingly, if PA has a favourable impact on sleep and psychological functioning, then data suggest that sports participation should be more tailored to increase motivation among female adolescents.


Assuntos
Exercício Físico/psicologia , Comportamento Exploratório , Saúde Mental , Sono/fisiologia , Adolescente , Feminino , Humanos , Masculino , Fatores Sexuais , Distúrbios do Início e da Manutenção do Sono/psicologia
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