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Article ; Online: Comparing the Effectiveness of the Triple P-Positive Parenting Program and Parenting Program of Acceptance and Commitment Therapy on Parent-Child Relationship and Self-efficacy of Mothers With Oppositional Defiant Disorder Children

Shahriar Amini Naghani / Samaneh Najarpourian / Seyaed Abdolvahhab Samavi

Journal of Research & Health, Vol 10, Iss 2, Pp 6-

2020 Volume 6

Abstract: Background: Parents may face challenges in establishing relationships with their children with Oppositional Defiant Disorder (ODD). This research was conducted to compare the effectiveness of the Triple P-Positive Parenting Program (Triple P) and the ... ...

Abstract	Background: Parents may face challenges in establishing relationships with their children with Oppositional Defiant Disorder (ODD). This research was conducted to compare the effectiveness of the Triple P-Positive Parenting Program (Triple P) and the Acceptance and Commitment Therapy (ACT)-based parenting on the parent-child relationship and parental self-efficacy of parents with ODD children. Methods: The design of this research was quasi-experimental and included two intervention groups and one control group. The study population consisted of all mothers of first-, second-, and third-grade primary school children with ODD who lived in Shahrekord City, Iran in 2018. The study mothers were chosen by purposive sampling method and then divided into three groups of Triple P, ACT, and control. Data were gathered using the Oppositional Defiant Disorder Rating Scale (ODDRS), the Parent-Child Relationship Scale (PCRS) and the Parental Self-Efficacy Questionnaire (PSEQ). Data analyses were carried out using multivariate analysis of variance, repeated measures analysis of variance and post hoc Bonferroni test in SPSS. Results: Significant differences in the Post-test parent-child relationship (F=4.53, P<0.05) and follow-up parent-child relationship (F=8.03, P<0.05) and Post-test parental self-efficacy (F=11.24, P<0.05) and follow-up parental self-efficacy (F=11.04, P<0.05) were observed among Triple P, ACT, and control group. The findings also showed no significant difference in post-test and follow-up phases (P>0.05) between Triple P and ACT groups. There were significant differences in parent-child relationships and parental self-efficacy between Pre-test and Post-test phases in Triple P and ACT (P<0.05) groups, but there was no significant difference between the Post-test and follow-up stages (P>0.05). Conclusion: The results of this research suggest that Triple P and ACT are effective techniques for improving parent-child relationships and parental self-efficacy in mothers of children with ODD.
Keywords	positive psychology ; acceptance and commitment ; oppositional defiant disorder ; parent-child relations ; self-efficacy ; Public aspects of medicine ; RA1-1270
Subject code	150
Language	English
Publishing date	2020-03-01T00:00:00Z
Publisher	Gonabad University of Medical Sciences
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The Potential of Gas Switching Partial Oxidation Using Advanced Oxygen Carriers for Efficient H 2 Production with Inherent CO 2 Capture

Carlos Arnaiz del Pozo / Schalk Cloete / Ángel Jiménez Álvaro / Felix Donat / Shahriar Amini

Applied Sciences, Vol 11, Iss 4713, p

2021 Volume 4713

Abstract: The hydrogen economy has received resurging interest in recent years, as more countries commit to net-zero CO 2 emissions around the mid-century. “Blue” hydrogen from natural gas with CO 2 capture and storage (CCS) is one promising sustainable hydrogen ... ...

Abstract	The hydrogen economy has received resurging interest in recent years, as more countries commit to net-zero CO 2 emissions around the mid-century. “Blue” hydrogen from natural gas with CO 2 capture and storage (CCS) is one promising sustainable hydrogen supply option. Although conventional CO 2 capture imposes a large energy penalty, advanced process concepts using the chemical looping principle can produce blue hydrogen at efficiencies even exceeding the conventional steam methane reforming (SMR) process without CCS. One such configuration is gas switching reforming (GSR), which uses a Ni-based oxygen carrier material to catalyze the SMR reaction and efficiently supply the required process heat by combusting an off-gas fuel with integrated CO 2 capture. The present study investigates the potential of advanced La-Fe-based oxygen carrier materials to further increase this advantage using a gas switching partial oxidation (GSPOX) process. These materials can overcome the equilibrium limitations facing conventional catalytic SMR and achieve direct hydrogen production using a water-splitting reaction. Results showed that the GSPOX process can achieve mild efficiency improvements relative to GSR in the range of 0.6–4.1%-points, with the upper bound only achievable by large power and H 2 co-production plants employing a highly efficient power cycle. These performance gains and the avoidance of toxicity challenges posed by Ni-based oxygen carriers create a solid case for the further development of these advanced materials. If successful, results from this work indicate that GSPOX blue hydrogen plants can outperform an SMR benchmark with conventional CO 2 capture by more than 10%-points, both in terms of efficiency and CO 2 avoidance.
Keywords	H 2 -power cogeneration ; gas switching partial oxidation ; gas switching reforming ; CO 2 capture and storage ; steam methane reforming ; blue hydrogen ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	660
Language	English
Publishing date	2021-05-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Simulation-Based Design and Economic Evaluation of a Novel Internally Circulating Fluidized Bed Reactor for Power Production with Integrated CO 2 Capture

Jan Hendrik Cloete / Mohammed N. Khan / Schalk Cloete / Shahriar Amini

Processes, Vol 7, Iss 10, p

2019 Volume 723

Abstract: Limiting global temperature rise to well below 2 °C according to the Paris climate accord will require accelerated development, scale-up, and commercialization of innovative and environmentally friendly reactor concepts. Simulation-based design can play ... ...

Abstract	Limiting global temperature rise to well below 2 °C according to the Paris climate accord will require accelerated development, scale-up, and commercialization of innovative and environmentally friendly reactor concepts. Simulation-based design can play a central role in achieving this goal by decreasing the number of costly and time-consuming experimental scale-up steps. To illustrate this approach, a multiscale computational fluid dynamics (CFD) approach was utilized in this study to simulate a novel internally circulating fluidized bed reactor (ICR) for power production with integrated CO 2 capture on an industrial scale. These simulations were made computationally feasible by using closures in a filtered two-fluid model (fTFM) to model the effects of important subgrid multiphase structures. The CFD simulations provided valuable insight regarding ICR behavior, predicting that CO 2 capture efficiencies and purities above 95% can be achieved, and proposing a reasonable reactor size. The results from the reactor simulations were then used as input for an economic evaluation of an ICR-based natural gas combined cycle power plant. The economic performance results showed that the ICR plant can achieve a CO 2 avoidance cost as low as $58/ton. Future work will investigate additional firing after the ICR to reach the high inlet temperatures of modern gas turbines.
Keywords	chemical looping combustion ; power production ; carbon capture ; internally circulating reactor ; reactor design ; fluidization ; techno-economics ; computational fluid dynamics ; filtered two-fluid model ; coarse-grid simulations ; Chemical technology ; TP1-1185 ; Chemistry ; QD1-999
Subject code	660
Language	English
Publishing date	2019-10-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Gas switching reforming (GSR) for power generation with CO2 capture: Process efficiency improvement studies

Nazir, Shareq Mohd / Jan Hendrik Cloete / Schalk Cloete / Shahriar Amini

Energy. 2019 Jan. 15, v. 167

2019

Abstract: This paper presents the process improvement studies of a combined cycle power plant integrated with a novel gas switching reforming (GSR) process for hydrogen production with integrated CO2 capture. The overall process is denoted as GSR-CC (gas switching ...

Abstract	This paper presents the process improvement studies of a combined cycle power plant integrated with a novel gas switching reforming (GSR) process for hydrogen production with integrated CO2 capture. The overall process is denoted as GSR-CC (gas switching reforming-combined cycle). Five cases are presented in which a systematic approach was adopted to improve the net electrical efficiency of the GSR-CC process. Two cases focus on reducing the number of unit operations and the other three cases focus on heat integration. The net electrical efficiency of the base case GSR-CC process is 45.8% whereas the improved GSR-CC has a net electrical efficiency of 51.1%. The efficiency penalty in the improved GSR-CC process is only 7.2 %-points with respect to the reference case natural gas combined cycle power plant without CO2 capture, and is less than post-combustion capture methods presented in literature. The CO2 avoidance in the GSR-CC is more than 95%. GSR-CC also gives a flexibility in the output from the plant in terms of pure H2 or electricity and the optimal plant configuration is designed to maximize this flexibility.
Keywords	carbon dioxide ; electricity ; heat ; hydrogen ; hydrogen production ; natural gas ; power generation ; power plants
Language	English
Dates of publication	2019-0115
Size	p. 757-765.
Publishing place	Elsevier Ltd
Document type	Article
ZDB-ID	2019804-8
ISSN	0360-5442 ; 0360-5442
ISSN (online)	0360-5442
ISSN	0360-5442
DOI	10.1016/j.energy.2018.11.023
Database	NAL-Catalogue (AGRICOLA)

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Article: Grid independence behaviour of fluidized bed reactor simulations using the Two Fluid Model: Detailed parametric study

Cloete, Schalk / Shahriar Amini / Stein Tore Johansen

Powder technology. 2016 Feb., v. 289

2016

Abstract: This short communication builds on previous work on the grid independence behaviour of the Two Fluid Model in reactive bubbling fluidized bed simulations. Regarding hydrodynamic grid independence behaviour (the numerical accuracy with which phase ... ...

Abstract	This short communication builds on previous work on the grid independence behaviour of the Two Fluid Model in reactive bubbling fluidized bed simulations. Regarding hydrodynamic grid independence behaviour (the numerical accuracy with which phase segregation was resolved), the particle relaxation time was confirmed as being directly proportional to the cell size achieving sufficiently grid independent behaviour. This relationship held over different particle sizes, particle densities, gas densities, gas viscosities and drag laws, but the slope of the proportionality changed for particle relaxation times above 0.4. For reactive grid independence behaviour (the numerical accuracy with which reactor performance was resolved), the relationship between the particle relaxation time and the sufficiently grid independent cell size was more complex, depending not only on the resolution of phase segregation, but also on the kinetic rate implemented and on the permeability of the emulsion phase. Simple and practical rules of thumb were proposed for estimating the sufficiently grid independent cell size for hydrodynamic and reactive simulations. For most practical purposes, the simpler and more accurate hydrodynamic grid independent cell size correlation can safely be used to run sufficiently accurate bubbling fluidized bed reactor simulations.
Keywords	emulsions ; fluidized beds ; hydrodynamics ; models ; particle size ; permeability ; powders ; viscosity
Language	English
Dates of publication	2016-02
Size	p. 65-70.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2015.11.011
Database	NAL-Catalogue (AGRICOLA)

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Article: Grid independence behaviour of fluidized bed reactor simulations using the Two Fluid Model: Effect of particle size

Cloete, Schalk / Shahriar Amini / Stein Tore Johansen

Powder technology. 2015 Jan., v. 269

2015

Abstract: It is well known that particle size has a significant influence on the grid independence behaviour of fluidized bed reactor simulations carried out using the Two Fluid Model (TFM) approach. The general rule of thumb states that the cell size should scale ...

Abstract	It is well known that particle size has a significant influence on the grid independence behaviour of fluidized bed reactor simulations carried out using the Two Fluid Model (TFM) approach. The general rule of thumb states that the cell size should scale linearly with the particle size so that the cell size is always at most a factor of 10 larger than the particle size. In this study, however, the effect of particle size on grid independence behaviour was shown to be unexpectedly large. In particular, a five-fold increase in particle size permitted the use of a 63 times larger cell size, implying a 633≈250,000 times speedup for resolved simulations in the planar 2D domain considered in this study. Thus, the general rule of thumb was found to be overly cautious, especially for larger particles. Closer investigation revealed the particle relaxation time to be a very good predictor of the grid independent cell size. Although this finding needs to be confirmed for parameters other than only the particle size, this relation can theoretically be used to greatly shorten the time-consuming grid independence studies that are required before any fluidized bed simulation campaign. In general, the rapid increase in cell size allowed by larger particle sizes showed that reasonably accurate industrial scale simulations (5m inner diameter reactor) are already possible in 2D for large particles (~600μm). If the 2D grid independence behaviour assessed in this study is extendible to 3D, larger particle sizes in the range of 500–1000μm can already be simulated in full 3D for reactor sizes ranging from 1–4m. Simulation of smaller particle sizes (<200μm) will remain out of reach for many decades to come, however, and a filtered coarse grid approach will definitely be required to make such simulations possible.
Keywords	fluidized beds ; models ; particle size ; powders
Language	English
Dates of publication	2015-01
Size	p. 153-165.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2014.08.055
Database	NAL-Catalogue (AGRICOLA)

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Article: Modelling study of two chemical looping reforming reactor configurations: looping vs. switching

Francisco Morgado, Joana / John Morud / Schalk Cloete / Shahriar Amini / Thomas Gurker

Powder technology. 2017 July 01, v. 316

2017

Abstract: Autothermal Chemical Looping Reforming (CLR) is a promising technology for hydrogen production with integrated CO2 separation. However, the interconnected CLR reactor configuration is expected to present significant scale up challenges, especially under ... ...

Abstract	Autothermal Chemical Looping Reforming (CLR) is a promising technology for hydrogen production with integrated CO2 separation. However, the interconnected CLR reactor configuration is expected to present significant scale up challenges, especially under the pressurized conditions required for high process efficiency. These challenges can be circumvented by carrying out the reduction/oxidation reactions in a single bubbling/turbulent fluidized bed alternatively fed with fuel and air, henceforth called gas switching reforming (GSR). The primary drawbacks of the GSR concept are the undesired mixing between fuel and nitrogen after the gas feed switch and the need for high temperature valves at the reactor outlet. The performance of the CLR and GSR concepts are compared using a generic phenomenological model, applicable over different fluidization regimes. Results showed that the GSR process is best operated by separating the reduction and reforming reactions, whereas these reactions occur simultaneously in the CLR fuel reactor. This fundamental difference led to lower fuel conversion, but a higher heating value syngas in the GSR process. Separation of reduction and reforming steps in the GSR concept also allows for the efficient utilization of the off-gas fuel from a PSA unit for high purity pressurized hydrogen production. This makes the GSR process more applicable to hydrogen production with integrated CO2 capture, whereas the CLR concept is better suited to power production with pre-combustion CO2 capture.
Keywords	air ; carbon dioxide ; fluidized beds ; fuels ; hydrogen production ; mixing ; models ; nitrogen ; oxidation ; powders ; power generation ; synthesis gas ; temperature
Language	English
Dates of publication	2017-0701
Size	p. 599-613.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2016.11.059
Database	NAL-Catalogue (AGRICOLA)

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Article: The sensitivity of filtered Two Fluid Model to the underlying resolved simulation setup

Cloete, Jan Hendrik / Federico Municchi / Schalk Cloete / Shahriar Amini / Stefan Radl

Powder technology. 2017 July 01, v. 316

2017

Abstract: The filtered Two Fluid Model (fTFM) is a promising approach for enabling large scale fluidized bed reactor simulations using multiphase flow modelling. A substantial amount of research has been conducted in this field to derive filtered closures for all ... ...

Abstract	The filtered Two Fluid Model (fTFM) is a promising approach for enabling large scale fluidized bed reactor simulations using multiphase flow modelling. A substantial amount of research has been conducted in this field to derive filtered closures for all applicable transport processes including drag, stresses, heat transfer, scalar transport and reactions. This work aims to investigate the effect of TFM closures used in the resolved simulations from which fTFM closures are derived in order to assess the degree of uncertainty stemming from this source. In addition, the filtering approach provides a good platform for building a detailed understanding of the effects of different TFM closures. Simulations showed that the drag model used in the resolved simulations had the most significant effect on the filtered quantities derived. Inclusion of a frictional pressure model also had a large influence in the dense regions of the domain. Selection of a more generic drag model and inclusion of a frictional pressure model is therefore recommended for future studies. Finally, results revealed that the effects of TFM closures on filtered quantities could be grouped into two categories: interphase transport (drag, heat transfer and reactions) and diffusive transport (stresses and scalar transport). This suggests a common methodology in terms of filtered model form for these two groups.
Keywords	heat transfer ; models ; powders ; uncertainty
Language	English
Dates of publication	2017-0701
Size	p. 265-277.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2016.11.064
Database	NAL-Catalogue (AGRICOLA)

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Article: Evaluation of wall friction models for riser flow

Cloete, Jan Hendrik / Schalk Cloete / Shahriar Amini / Stefan Radl

Powder technology. 2016 Dec., v. 303

2016

Abstract: Two different approaches for modelling the particle-wall collisions, the frequently employed Johnson & Jackson model and the recently proposed Schneiderbauer model, were evaluated in a fluidized bed riser by comparing simulation results to experimental ... ...

Abstract	Two different approaches for modelling the particle-wall collisions, the frequently employed Johnson & Jackson model and the recently proposed Schneiderbauer model, were evaluated in a fluidized bed riser by comparing simulation results to experimental data over a range of fluidization velocities and solids fluxes. For the Johnson & Jackson model, it was shown that partial slip settings recommended for denser fluidization conditions (a specularity coefficient in the order of 0.1) failed to predict cluster formation at the walls at higher gas flow rates due to unrealistically large granular temperature generation in the near-wall regions. By reducing wall friction to settings approaching a free-slip condition (specularity coefficient in the order of 0.001), this problem is overcome by eliminating excessive granular temperature generation from over-predicted strain rates at the walls. However, this approach results in an overestimation of the downward velocity of the clusters at the wall in dense cases. Despite this shortcoming, predictions are remarkably accurate for most of the cases. The Schneiderbauer model, with model parameters close to recommended settings, performs similarly well for most of the cases, slightly under-predicting cluster formation at the walls in the dilute cases. Generally, it also predicts more realistic flow behaviour since it prevents dense clusters from falling rapidly at the walls. The Schneiderbauer wall friction model is therefore recommended for use in future studies of risers, since it is able to deliver reasonable results over a wider range of flow conditions than the Johnson and Jackson model, using a single set of friction parameters. Furthermore, it has the benefit of using experimentally measurable quantities as input.
Keywords	deformation ; fluidized beds ; friction ; models ; powders ; prediction ; temperature
Language	English
Dates of publication	2016-12
Size	p. 156-167.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2016.07.009
Database	NAL-Catalogue (AGRICOLA)

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Article: Experimental investigation on the generic effects of gas permeation through flat vertical membranes

Wassie, Solomon A / Abdelghafour Zaabout / Fausto Gallucci / Martin van Sint Annaland / Schalk Cloete / Shahriar Amini

Powder technology. 2017 July 01, v. 316

2017

Abstract: This work reports the effects of gas extraction through flat vertical membranes on bubble dynamics in a fluidized bed. Bubble properties such as size, number, velocity and shape play a key role in the hydrodynamics and consequently heat and mass transfer ...

Abstract	This work reports the effects of gas extraction through flat vertical membranes on bubble dynamics in a fluidized bed. Bubble properties such as size, number, velocity and shape play a key role in the hydrodynamics and consequently heat and mass transfer characteristics of fluidized bed (membrane) reactors. Thus the main focus of this work is to understand the bubble behaviour over different fluidization velocities, particle sizes, gas extraction rates and gas extraction locations. A pseudo 2D experimental setup with flat vertical porous plates placed at the back of the column was used for simulating gas extraction through a flat vertical membrane in a fluidized bed reactor. A Digital Image Analysis (DIA) experimental technique was applied in order to extract the bubble properties.Experimental results showed that the variation of gas extraction fraction has a minor effect on the bubble dynamics, with significant effects only present for high extraction rates and small particle sizes. Shifting the location of gas extraction more towards the centre of the bed had a larger influence on bubble dynamics. Deactivation of the two outmost membranes created a more uniform lateral bubble distribution profile which would be beneficial for reactor performance. However, deactivation of additional membranes caused the formation of central densified zones which obstructed the rising gas from reaching the central membranes. These effects could be clearly observed for small particles (196μm), while larger particles (500μm) showed little or no sensitivity to changes in gas extraction rate or location.
Keywords	digital images ; fluidized beds ; heat ; hydrodynamics ; image analysis ; mass transfer ; particle size ; powders
Language	English
Dates of publication	2017-0701
Size	p. 207-217.
Publishing place	Elsevier B.V.
Document type	Article
ISSN	0032-5910
DOI	10.1016/j.powtec.2016.12.026
Database	NAL-Catalogue (AGRICOLA)

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