scholarly journals Simulation aided analysis and experimental study of polyurethane polymerization reaction and foaming process

2017 ◽  
Author(s):  
◽  
Harith H. Al-Moameri
Keyword(s):  
Mass Transfer ◽  
Reaction Temperature ◽  
Research Process ◽  
Polymerization Reaction ◽  
Gel Point ◽  
Foam Formation ◽  
Simulation Code ◽  
Mass Transfer Limitation ◽  
Elementary Reactions ◽  
The Impact

A MatLab simulation model was developed to simulate polymerization reactions, gel point times and foam formation. The simulation is based on the simultaneous solution of typically 25-80 ordinary differential equations that describe elementary reactions, energy balances, and mass transfer. Laboratory polymerization experiments were performed to evaluate the accuracy of the simulations, including setting up experimental systems and measurement of temperature, height, and viscosity profiles of the urethane systems. The performance of physical and chemical blowing agents were simulated with mass transfer of the blowing agent estimated as a function of reaction temperature and resin viscosity. The simulation code of polyurethane reactions allows the studying of variables that are impossible to obtain in labs like the rate of foam's cell growth and pressure inside the cells. Also, simulation provides insight into mechanisms such as how attaining a reasonable maximum reaction temperature is important to properly cure foams and avoid foam shrinkage. The impact of mass transfer limitation of the reacting moieties was successfully simulated based on three fundamental approaches. Further modeling shows the ability to reduce the number of parameters used for simulating urethane reactions by considering the viscosity dependent term for the frequency factor of Arrhenius equation. Finally, the simulation studies of this research provide fundamental insights into the mechanism of homogeneous and catalytic reactions. This research process places high demands on identifying and testing highly-impactful fundamental mechanisms during polymerization that have not previously been identified.

scholarly journals The Impact of Iron Oxide Concentration on the Performance of Molten Oxide Electrolytes for the Production of Liquid Iron Metal

2019 ◽  
Vol 51 (1) ◽  
pp. 365-376
Author(s):  
Jan Wiencke ◽  
Hervé Lavelaine ◽  
Pierre-Jean Panteix ◽  
Carine Petitjean ◽  
Christophe Rapin
Keyword(s):  
Mass Transfer ◽  
Iron Oxide ◽  
Liquid Iron ◽  
Mass Transfer Limitation ◽  
Oxide Concentration ◽  
Ohmic Drop ◽  
Geometrical Form ◽  
Flow Through ◽  
Molten Oxide ◽  
The Impact

AbstractThe effect of iron oxide concentration on the conductive behavior of a molten oxide electrolyte has been investigated at 1823 K using stepped linear scan voltammetry. To maximize the current flow through the electrolyte the ohmic drop in the cell was minimized by shortening the electrode distance. The acquired current was then interpreted by means of an ohmic drop correction, taking into account the conductivity of the alumina-silicate electrolyte and the geometrical form factor of the cell. Via this methodology, a mass transfer limitation in dependence of the iron oxide concentration was identified. This mass transfer limitation vanishes above 7 wt pct of iron oxide where charge transfer starts to be limited solely by electrochemical reaction kinetics. In the analyzed range of concentration, an impact of iron oxide on electronic conduction was not measurable. In addition to these findings, the faradaic yield of the anode half-reaction was determined by the life-measure of O2-production. Hereby, a domain of an anodic yield close to 100 pct for various iron oxide concentrations was identified. Based on these findings, suitable conditions for the electrochemical production of liquid iron were determined.

scholarly journals Key parameters controlling an adsorption process for the selective removal of arsenic from drinking water

2002 ◽  
Vol 2 (5-6) ◽  
pp. 111-117 ◽  
Author(s):  
S. Ouvrard ◽  
M.-O. Simonnot ◽  
M. Sardin
Keyword(s):  
Mass Transfer ◽  
Adsorption Process ◽  
Fine Particles ◽  
Mass Transfer Limitation ◽  
Water Ph ◽  
Regeneration Procedure ◽  
Removal Of Arsenic ◽  
The Impact ◽  
Elution Step ◽  
Flow Rate Influence

Arsenic can be selectively removed from water through adsorption on a natural manganese oxide. This paper presents some of the key parameters controlling such a process. Both production and regeneration steps were studied and the influence of three main controlling parameters was put to light. The water pH greatly influenced the adsorption capacity. Low water pH highly improved the treatment. The adsorption being under mass transfer limitation, flow rate influence was measured and optimization solutions were proposed. Finally, the impact of the regeneration procedure was evaluated on the adsorbent stability. It gave good arsenic elution results but the caustic elution step generated fine particles that could not be avoided. The following neutralization could however be adjusted in order to minimize further adsorbent dissolution.

Public space of the trustworthiness of sociological knowledge: The case of electoral research

2020 ◽  
pp. 13-22
Author(s):  
OLEKSANDR STEGNII
Keyword(s):  
Public Space ◽  
Research Process ◽  
Negative Influence ◽  
Election Campaign ◽  
Sociological Research ◽  
Good Tool ◽  
Sociological Knowledge ◽  
The Public ◽  
Approval Ratings ◽  
The Impact

The paper analyses specific features of sociological data circulation in a public space during an election campaign. The basic components of this kind of space with regard to sociological research are political actors (who put themselves up for the election), voters and agents. The latter refer to professional groups whose corporate interests are directly related to the impact on the election process. Sociologists can also be seen as agents of the electoral process when experts in the field of electoral sociology are becoming intermingled with manipulators without a proper professional background and publications in this field. In a public space where an electoral race is unfolding, empirical sociological research becomes the main form of obtaining sociological knowledge, and it is primarily conducted to measure approval ratings. Electoral research serves as an example of combining the theoretical and empirical components of sociological knowledge, as well as its professional and public dimensions. Provided that sociologists meet all the professional requirements, electoral research can be used as a good tool for evaluating the trustworthiness of results reflecting the people’s expression of will. Being producers of sociological knowledge, sociologists act in two different capacities during an election campaign: as analysts and as pollsters. Therefore, it is essential that the duties and areas of responsibility for professional sociologists should be separated from those of pollsters. Another thing that needs to be noted is the negative influence that political strategists exert on the trustworthiness of survey findings which are going to be released to the public. Using the case of approval ratings as an illustration, the author analyses the most common techniques aimed at misrepresenting and distorting sociological data in the public space. Particular attention is given to the markers that can detect bogus polling companies, systemic violations during the research process and data falsification.

scholarly journals Biogas Dry Reforming for Hydrogen through Membrane Reactor Utilizing Negative Pressure

Fuels ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 194-209
Author(s):  
Akira Nishimura ◽  
Tomohiro Takada ◽  
Satoshi Ohata ◽  
Mohan Lal Kolhe
Keyword(s):  
Energy Source ◽  
Reaction Temperature ◽  
Negative Pressure ◽  
Membrane Reactor ◽  
Reaction Chamber ◽  
Dry Reforming ◽  
Molar Ratio ◽  
Effect Of Pressure ◽  
The Impact

Biogas, consisting of CH4 and CO2, is a promising energy source and can be converted into H2 by a dry reforming reaction. In this study, a membrane reactor is adopted to promote the performance of biogas dry reforming. The aim of this study is to investigate the effect of pressure of sweep gas on a biogas dry reforming to get H2. The effect of molar ratio of supplied CH4:CO2 and reaction temperature is also investigated. It is observed that the impact of psweep on concentrations of CH4 and CO2 is small irrespective of reaction temperature. The concentrations of H2 and CO increase with an increase in reaction temperature t. The concentration of H2, at the outlet of the reaction chamber, reduces with a decrease in psweep. It is due to an increase in H2 extraction from the reaction chamber to the sweep chamber. The highest concentration of H2 is obtained in the case of the molar ratio of CH4:CO2 = 1:1. The concentration of CO is the highest in the case of the molar ratio of CH4:CO2 = 1.5:1. The highest sweep effect is obtained at reaction temperature of 500 °C and psweep of 0.045 MPa.

scholarly journals 10.B. Workshop: Corporate influence on science – what is happening and what can be done?

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
◽  
Keyword(s):  
Fossil Fuels ◽  
Conflicts Of Interest ◽  
Research Process ◽  
Policy Outcomes ◽  
Policy And Practice ◽  
Industry Funding ◽  
Corporate Influence ◽  
Pharmaceutical Industries ◽  
The Impact ◽  
Funding Research

Abstract The role of the corporate sector in research sponsorship is growing. So too is the evidence that corporations whose products are potentially damaging to health or the environment influence science and the ways in which science is used in policy and practice. Such efforts are a key part of corporate attempts to maintain or increase the consumption or use of industry products, and to secure favourable policy outcomes. The products and practices of corporations are responsible for a growing proportion of the global disease burden. Non-communicable diseases, many driven by consumption of unhealthy commodities and exposure to chemicals, account for over 73 percent of global deaths. It is increasingly important to understand the complex and multifaceted ways corporations seek to influence science; the impact these strategies have; and the ways this influence can be addressed. This workshop brings together global experts to explore these issues. Drawing on examples from several industries (e.g. tobacco, alcohol, food, and pharmaceuticals), it aims to: Increase understanding of the ways corporations whose products are potentially damaging to health influence science. We present a newly developed, evidence-based typology which draws together the vast existing literature in this field, to present a simplified way of understanding corporate influence on science. Delegates will be provided with materials that provide a means for recognising such influence.Examine the influence that corporations have on the first stage in the research process - research agendas. We present examples from tobacco, food and pharmaceutical industries which illustrate the mechanism through which industry funding of science drives researchers to study questions that are favourable to industry. The desired outcome is to maximise research on the benefits of industry products (positioning these products as solutions to complex problems), minimise research on the harms of their products, support their policy and legal positions, and impede potential regulation of their products.Increase awareness of the involvement that corporations have had in altering the mechanisms though which science is used in policymaking. Delegates will hear how corporations promoted and embedded policymaking reforms which increase reliance on and provide a conduit for industry-favourable science.Suggest ways forward concerning management of conflicts of interest in the publication of health research. Here we will discuss the roles that journals can play in governing conflicts of interest and issues of transparency in the publication of academic research.Suggest ways forward for funding research on unhealthy commodities. We present criteria for tobacco industry-supported research funding programs, and discuss the applicability of similar programs for funding research on other unhealthy commodities, and on the practices of other industries such as the fossil fuels industry. Key messages Corporations have been seen to skew evidence bases, manipulate interpretations of science, and influence use of science in policy and practice – such influence is a major threat to public health. This workshop exposes industry tactics in this area and begins to identify ways for dealing with them.

scholarly journals Understanding adherence to reactive treatment of asymptomatic malaria infections in The Gambia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fatou Jaiteh ◽  
Joseph Okebe ◽  
Yoriko Masunaga ◽  
Umberto D’Alessandro ◽  
Jane Achan ◽  
...  
Keyword(s):  
Day Treatment ◽  
Treatment Completion ◽  
Clinical Malaria ◽  
Research Process ◽  
The Gambia ◽  
Individual Compound ◽  
Asymptomatic Malaria ◽  
High Coverage ◽  
Major Health Problem ◽  
The Impact

AbstractThe impact of different types of reactive case detection and/or treatment strategies for malaria elimination depends on high coverage and participants’ adherence. However, strategies to optimise adherence are limited, particularly for people with asymptomatic or no infections. As part of a cluster-randomized trial to evaluate the effect of reactive treatment in The Gambia, all residents in the compound of a diagnosed clinical malaria patient received dihydro-artemisinin–piperaquine (DP). Using a mixed method approach, we assessed which factors contribute to adherence among the contacts of malaria cases that showed no symptoms. Adherence was defined as the proportion of compound members that (1) returned all medicine bags empty and (2) self-reported (3-day) treatment completion. Among the 273 individuals from 14 compounds who received DP, 227 (83.1%) were available for and willing to participate in the survey; 85.3% (233/273) returned empty medicine bags and 91.6% (208/227) self-reported treatment completion. Although clinical malaria was not considered a major health problem, reported adherence was high. The drivers of adherence were the strong sense of responsibility towards protecting the individual, compound and the village. Adherence can be optimised through a transdisciplinary implementation research process of engaging communities to bridge the gap between research goals and social realities.

Thinking Outside the Circle: Reflections on Theory and Methods for School-Based Garden Research

2017 ◽  
Vol 47 (2) ◽  
pp. 139-145 ◽  
Author(s):  
Liesa Clague ◽  
Neil Harrison ◽  
Katherine Stewart ◽  
Caroline Atkinson
Keyword(s):  
Research Process ◽  
Philosophical Approach ◽  
Approach To Learning ◽  
Australian Aboriginal ◽  
Cultural Integrity ◽  
School Based ◽  
Language Groups ◽  
Considerable Research ◽  
The Impact ◽  
Deep Listening

School-based gardens (SBGs) are contributing to improvements in many areas of education, including nutrition, health, connectedness and engagement of students. While considerable research has been conducted in other parts of the world, research in Australia provides limited understanding of the impact of SBGs. The aim of this paper is to give a reflective viewpoint on the impact of SBGs in Australia from the perspective of an Aboriginal philosophical approach called Dadirri. The philosophy highlights an Australian Aboriginal concept, which exists but has different meanings across Aboriginal language groups. This approach describes the processes of deep and respectful listening. The study uses photovoice as a medium to engage students to become researchers in their own right. Using this methodology, students have control over how they report what is significant to them. The use of photovoice as a data collection method is contextualised within the Aboriginal philosophical approach to deep listening. For the first author, an Aboriginal researcher (Clague), the journey is to find a research process that maintains cultural integrity and resonates with the participants by affirming that a culturally sensitive approach to learning is important.

scholarly journals Numerical Simulation of Heat Mass Transfer Effects on MHD Flow of Williamson Nanofluid by a Stretching Surface with Thermal Conductivity and Variable Thickness

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 684
Author(s):  
Saeed Islam ◽  
Haroon Ur Rasheed ◽  
Kottakkaran Sooppy Nisar ◽  
Nawal A. Alshehri ◽  
Mohammed Zakarya
Keyword(s):  
Thermal Conductivity ◽  
Boundary Layer ◽  
Mass Transfer ◽  
Differential Equations ◽  
Variable Thickness ◽  
Heat Mass Transfer ◽  
Mathematical Formulation ◽  
Stretching Surface ◽  
Nanofluid Flow ◽  
The Impact

The current analysis deals with radiative aspects of magnetohydrodynamic boundary layer flow with heat mass transfer features on electrically conductive Williamson nanofluid by a stretching surface. The impact of variable thickness and thermal conductivity characteristics in view of melting heat flow are examined. The mathematical formulation of Williamson nanofluid flow is based on boundary layer theory pioneered by Prandtl. The boundary layer nanofluid flow idea yields a constitutive flow laws of partial differential equations (PDEs) are made dimensionless and then reduce to ordinary nonlinear differential equations (ODEs) versus transformation technique. A built-in numerical algorithm bvp4c in Mathematica software is employed for nonlinear systems computation. Considerable features of dimensionless parameters are reviewed via graphical description. A comparison with another homotopic approach (HAM) as a limiting case and an excellent agreement perceived.

Librarians, step out of the classroom!: how improved faculty-led IL instruction improves student learning

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Meagan Lacy ◽  
Alexandra Hamlett
Keyword(s):  
Student Learning ◽  
Research Process ◽  
Control Group ◽  
Student Survey ◽  
Content Type ◽  
Actual Application ◽  
Faculty Teaching ◽  
Survey Results ◽  
The Impact

PurposeIn most higher education institutions, information literacy (IL) instruction is usually considered the purview of librarians, not disciplinary faculty. However, a small but growing body of research indicates that students learn the research process best when these skills are taught in the context of a course or a discipline. For this reason, teaching faculty should share ownership of IL instruction — but how? In this case study, community college librarians explain how they successfully trained faculty to integrate IL into their English Composition courses and teach IL independently.Design/methodology/approachUsing a multimethods approach, the investigators draw on faculty interviews, student surveys, and content analysis of student essays to evaluate the impact of faculty-led IL instruction on student learning after one semester.FindingsFaculty reported that their instruction of IL was improved, and students work better as a result of their collaboration with the librarians. Compared to previous semesters, faculty perceived gains in terms of students’ ability to synthesize and cite evidence in their writing. Student survey results indicate perceived gains in their IL skills, but an assessment of their written work reveals a discrepancy between this perception and the actual application of these skills.Research limitations/implicationsBecause there is no control group, no conclusions can be drawn as to whether faculty-led IL instruction is as effective as librarian-led IL instruction or whether students’ academic performance improves due to faculty teaching IL. However, the purpose of this study is primarily descriptive. It addresses how other libraries may create a culture of shared ownership of IL instruction on their campuses.Practical implicationsThis study offers an alternative model to library instruction and suggests ways instruction librarians can prioritize their outreach and instructional efforts to maximize impact on student learning.Originality/valueWhile much has been written about how librarians can improve IL instruction, few studies mention the role of faculty. This case study starts the conversation.

scholarly journals Assistive tools for disability arts: collaborative experiences in working with disabled artists and stakeholders

2016 ◽  
Vol 10 (2) ◽  
pp. 121-129 ◽  
Author(s):  
Chris Creed
Keyword(s):  
Special Needs ◽  
Research Impact ◽  
Research Process ◽  
Research Approach ◽  
Visual Artists ◽  
Content Type ◽  
British Council ◽  
Artistic Work ◽  
Conducting Research ◽  
The Impact

Purpose – The purpose of this paper is to provide a review of the experiences in working collaboratively with physically impaired visual artists and other stakeholders (e.g. disability arts organisations, charities, personal assistants, special needs colleges, assistive technologists, etc.) to explore the potential of digital assistive tools to support and transform practice. Design/methodology/approach – The authors strategically identified key organisations as project partners including Disability Arts Shropshire, Arts Council England, the British Council, SCOPE, and National Star College (a large special needs college). This multi-disciplinary team worked together to develop relationships with disabled artists and to collaboratively influence the research focus around investigating the current practice of physically impaired artists and the impact of digital technologies on artistic work. Findings – The collaborations with disabled artists and stakeholders throughout the research process have enriched the project, broadened and deepened research impact, and enabled a firsthand understanding of the issues around using assistive technology for artistic work. Artists and stakeholders have become pro-active collaborators and advocates for the project as opposed to being used only for evaluation purposes. A flexible research approach was crucial in helping to facilitate research studies and enhance impact of the work. Originality/value – This paper is the first to discuss experiences in working with physically impaired visual artists – including the benefits of a collaborative approach and the considerations that must be made when conducting research in this area. The observations are also relevant to researchers working with disabled participants in other fields.

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