Search results for: chemical and physical characterization
Commenced in January 2007
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Paper Count: 11300

Search results for: chemical and physical characterization

3230 Quality of Life and Self-Assessed Health of Buprenorphine–Maintained Opiate Addicts

Authors: Igna Brajević Gizdić, Gorka Vuletić

Abstract:

Introduction: Addiction is a chronic brain relapsing disorder. Opioid Substitution Therapy (OST) using buprenorphine as a medical treatment option shows as a promising option for achieving and maintaining abstinence in opioid-addicted patients. This research aimed to determine and evaluate the quality of life (QoL) in opiate-addicted patients after five years of buprenorphine therapy. Method: The total sample included 44 buprenorphine-maintained opiate addicts in outpatient treatment. The participants were administered the QoL questionnaire (WHOQOL-BREF) at two-time points (T1 and T2) with an interval of at least five years. WHOQOL-BREF contains a total of 26 questions. The first two questions, related to overall QoL and general health status, and the remaining questions (3–26), which represented four domains—physical, psychological, social, and environmental health—were evaluated separately. Results: The results indicated no significant differences in overall self-assessed QoL nor in individual domains after five years (T2) of abstinence with OST buprenorphine- maintenance. Conclusion: These findings indicated no improvement in QoL of buprenorphine-maintenance opiate addicts in outpatient treatment. However, this might be due to the smaller sample size and participants' overall high scores in QoL at T1. This study suggests the importance of expectations when considering the QoL and general health of buprenorphine-maintenance opiate addicts in outpatient treatment.

Keywords: abstinence, addicts, buprenorphine, opioid substitution therapy, quality of life

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3229 Study of Mechanical Properties of Glutarylated Jute Fiber Reinforced Epoxy Composites

Authors: V. Manush Nandan, K. Lokdeep, R. Vimal, K. Hari Hara Subramanyan, C. Aswin, V. Logeswaran

Abstract:

Natural fibers have attained the potential market in the composite industry because of the huge environmental impact caused by synthetic fibers. Among the natural fibers, jute fibers are the most abundant plant fibers which are manufactured mainly in countries like India. Even though there is a good motive to utilize the natural supplement, the strength of the natural fiber composites is still a topic of discussion. In recent days, many researchers are showing interest in the chemical modification of the natural fibers to increase various mechanical and thermal properties. In the present study, jute fibers have been modified chemically using glutaric anhydride at different concentrations of 5%, 10%, 20%, and 30%. The glutaric anhydride solution is prepared by dissolving the different quantity of glutaric anhydride in benzene and dimethyl-sulfoxide using sodium formate catalyst. The jute fiber mats have been treated by the method of retting at various time intervals of 3, 6, 12, 24, and 36 hours. The modification structure of the treated fibers has been confirmed with infrared spectroscopy. The degree of modification increases with an increase in retention time, but higher retention time has damaged the fiber structure. The unmodified fibers and glutarylated fibers at different retention times are reinforced with epoxy matrix under room temperature. The tensile strength and flexural strength of the composites are analyzed in detail. Among these, the composite made with glutarylated fiber has shown good mechanical properties when compared to those made of unmodified fiber.

Keywords: flexural properties, glutarylation, glutaric anhydride, tensile properties

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3228 Effect of Tensile Strain on Microstructure of Irradiated Core Internal Material

Authors: Hygreeva Kiran Namburi, Anna Hojna, Edita Lecianova, Fencl Zdenek

Abstract:

Irradiation Assisted Stress Corrosion Cracking [IASCC] is one of the most significant environmental degradation in the internal components made from Austenitic stainless steel. This mechanism is still not fully understood and there are no suitable criteria for prediction of the damage during operation. In this work, core basket material 08Ch18N10T austenitic stainless steel acquired from decommissioned NPP Nord / Greifswald Unit 1, VVER 440-230 type, operated for 15 years and irradiated at 5.2 dpa is studied. This material was tensile tested at two different test temperatures and strain rates in air and at the elevated temperature under the water environment. SEM observations of the fracture surface documented ductile fracture of the samples tested in air, but areas of IASCC tested in water. This paper emphasizes on the microscopic examination results from the mechanically tested samples to determine the underlying IASCC physical damage process. TEM observations of thin foils made from the gauge sections that are closer to the fractured surface of the specimen aimed to find variances in interaction of dislocations and grain boundaries owing to different test conditions.

Keywords: irradiation assisted stress corrosion cracking, core basket material, SEM observations of the fracture surface, microscopic examination results

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3227 A Novel Approach to Design and Implement Context Aware Mobile Phone

Authors: G. S. Thyagaraju, U. P. Kulkarni

Abstract:

Context-aware computing refers to a general class of computing systems that can sense their physical environment, and adapt their behaviour accordingly. Context aware computing makes systems aware of situations of interest, enhances services to users, automates systems and personalizes applications. Context-aware services have been introduced into mobile devices, such as PDA and mobile phones. In this paper we are presenting a novel approaches used to realize the context aware mobile. The context aware mobile phone (CAMP) proposed in this paper senses the users situation automatically and provides user context required services. The proposed system is developed by using artificial intelligence techniques like Bayesian Network, fuzzy logic and rough sets theory based decision table. Bayesian Network to classify the incoming call (high priority call, low priority call and unknown calls), fuzzy linguistic variables and membership degrees to define the context situations, the decision table based rules for service recommendation. To exemplify and demonstrate the effectiveness of the proposed methods, the context aware mobile phone is tested for college campus scenario including different locations like library, class room, meeting room, administrative building and college canteen.

Keywords: context aware mobile, fuzzy logic, decision table, Bayesian probability

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3226 Cognitive Fusion and Obstacles to Valued Living: Beyond Pain-Specific Events in Chronic Pain

Authors: Sergio A. Carvalho, Jose Pinto-Gouveia, David Gillanders, Paula Castilho

Abstract:

The role of psychological processes has long been recognized as crucial factors in depressive symptoms in chronic pain (CP). Although some studies have explored the negative impact of being entangled with internal experiences (e.g., thoughts, emotions, physical sensations) – cognitive fusion, it is not extensively explored 1) whether these are pain-related or rather general difficult experiences, and 2) how they relate to experiencing obstacles in committing to valued actions. The current study followed a cross-sectional design in a sample of 231 participants with CP, in which a mediational model was tested through path analyses in AMOS software. The model presented a very good model fit (Χ²/DF = 1.161; CFI = .999; TLI = .996; RMSEA = .026, PCLOSE = .550.), and results showed that pain intensity was not directly related to depressive symptoms (β = .055; p = .239) but was mediated by cognitive fusion with both general and pain-related internal experiences (β = .181, 95%CI [.097; .271]; p = .015). Additionally, results showed that only general cognitive fusion (but not pain-specific fusion) was associated with experiencing obstacles to living a meaningful life, which mediated its impact on depressive symptoms (β = .197, 95%CI [.102; .307]; p = .001). Overall, this study adds on current literature by suggesting that psychological interventions to pain management should not be focused only on management of pain-related experiences, but also on developing more effective ways of relating to overall internal experiences.

Keywords: cognitive fusion, chronic pain, depressive symptoms, valued living

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3225 Failure Analysis of Fuel Pressure Supply from an Aircraft Engine

Authors: M. Pilar Valles-gonzalez, Alejandro Gonzalez Meije, Ana Pastor Muro, Maria Garcia-Martinez, Beatriz Gonzalez Caballero

Abstract:

This paper studies a failure case of a fuel pressure supply tube from an aircraft engine. Multiple fracture cases of the fuel pressure control tube from aircraft engines have been reported. The studied set was composed of the mentioned tube, a welded connecting pipe, where the fracture has been produced, and a union nut. The fracture has been produced in one most critical zones of the tube, in a region next to the supporting body of the union nut to the connector. The tube material was X6CrNiTi18-10, an austenitic stainless steel. Chemical composition was determined using an X-Ray fluorescence spectrometer (XRF) and combustion equipment. Furthermore, the material has been mechanical, by hardness test, and microstructural characterized using a stereomicroscope and an optical microscope. The results confirmed that it is within specifications. To determine the macrofractographic features, a visual examination and a stereo microscope of the tube fracture surface have been carried out. The results revealed a tube plastic macrodeformation, surface damaged, and signs of a possible corrosion process. Fracture surface was also inspected by scanning electron microscopy (FE-SEM), equipped with a microanalysis system by X-ray dispersive energy (EDX), to determine the microfractographic features in order to find out the failure mechanism involved in the fracture. Fatigue striations, which are typical from a progressive fracture by a fatigue mechanism, have been observed. The origin of the fracture has been placed in defects located on the outer wall of the tube, leading to a final overload fracture.

Keywords: aircraft engine, fatigue, FE-SEM, fractography, fracture, fuel tube, microstructure, stainless steel

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3224 Monstrous Beauty: Disability and Illness in Contemporary Pop Culture

Authors: Grzegorz Kubinski

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In the proposed paper, we would like to present the phenomenon of disease and disability as an element of discourse redefining the contemporary canons of beauty and the category of normativity. In widely understood media, and above all in social media and fashion industry, the use of the disease as an aesthetic category has long been observed. There is an interesting case of promoting and maintaining a certain, ideal pattern of physical beauty, while at the same time very clear exploitation of various types of illnesses. The categories of disease and disabled body are shown as an element of the expression of the individuality and originality of one's own identity, while at the same time the disabled person is still experiencing social exclusion. Illness or body abnormality as an aesthetic category also functions as an ethical-political category. The analysis of the interrelations of these discourses will be presented on the example of selected projects present in social media, like Instagram or Facebook. We would like to present how old forms of 'curiosities' or 'abnormalities' turned into mainstream forms of a new aesthetic. For marginalized disabled people, there is a new form of expression and built their identity. But, there is an interesting point: are this contemporary forms of using disability and illness really new? Or maybe this is just another form of Wunderkammer or even cabinets of curiosities? We propose to analyze contemporary cultural and social context in order to clarify this issue. On the other hand, we would like to present some examples from personal interviews with disabled internet influencers and statements disabled persons concerning the role of the different body in society (e.g. #bodypositive, #perfeclyflawed).

Keywords: disability, new media, defect, fashion

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3223 A Comparative Study of Single- and Multi-Walled Carbon Nanotube Incorporation to Indium Tin Oxide Electrodes for Solar Cells

Authors: G. Gokceli, O. Eksik, E. Ozkan Zayim, N. Karatepe

Abstract:

Alternative electrode materials for optoelectronic devices have been widely investigated in recent years. Since indium tin oxide (ITO) is the most preferred transparent conductive electrode, producing ITO films by simple and cost-effective solution-based techniques with enhanced optical and electrical properties has great importance. In this study, single- and multi-walled carbon nanotubes (SWCNT and MWCNT) incorporated into the ITO structure to increase electrical conductivity, mechanical strength, and chemical stability. Carbon nanotubes (CNTs) were firstly functionalized by acid treatment (HNO3:H2SO4), and the thermal resistance of CNTs after functionalization was determined by thermogravimetric analysis (TGA). Thin films were then prepared by spin coating technique and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), four-point probe measurement system and UV-Vis spectrophotometer. The effects of process parameters were compared for ITO, MWCNT-ITO, and SWCNT-ITO films. Two factors including CNT concentration and annealing temperature were considered. The UV-Vis measurements demonstrated that the transmittance of ITO films was 83.58% at 550 nm, which was decreased depending on the concentration of CNT dopant. On the other hand, both CNT dopants provided an enhancement in the crystalline structure and electrical conductivity. Due to compatible diameter and better dispersibility of SWCNTs in the ITO solution, the best result in terms of electrical conductivity was obtained by SWCNT-ITO films with the 0.1 g/L SWCNT dopant concentration and heat-treatment at 550 °C for 1 hour.

Keywords: CNT incorporation, ITO electrode, spin coating, thin film

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3222 Investigation of Kinesiophobia in Individuals with Type 2 Diabetes

Authors: Ismail Okur, Betul Taspinar, Turkan Pasali Kilit, Eda O. Okur, Ferruh Taspinar

Abstract:

Type 2 Diabetes Mellitus (T2DM) is one of the most important global health emergencies and every year more and more people are affected by T2DM. T2DM causes life-changing complications by affecting organ and systems. Although diet and exercise are the best way to treat patients with T2DM, those patients generally have a sedentary life style. This study was planned to determine whether patients with T2DM have kinesiophobia (fear of movement). A controlled trial was conducted on 87 adults. Forty-one individuals with T2DM (study group, 34 female and 7 male) and 46 nondiabetic individuals (control group, 39 female and 7 male) were included in the study. Patients were screened for fear of movement using the Tampa Scale for Kinesiophobia (TSK). The data including age, sex, weight, height, and TSK scores were obtained. Mann Whitney U test were used to analyse the data. The mean ages and BMI of study and control groups were 51.98 ± 6.03 year and 49.52 ± 5.61 year and 31.82 ± 2.88 kg/m2 and 30.22 ± 2.91 kg/m2, respectively. The groups have similar demographic properties. The kinesiophobia scores of study and control groups were 42.78 ± 5.50 and 39.48 ± 5.05, respectively and the difference was statistically significant (p=0.05). This study showed that patients with T2DM had high kinesiophobia scores rather than nondiabetics. Those patients might avoid to do exercise. In other words, patients with T2DM might have lower physical activity level. Therefore the authors suggest that to evaluate and interfere with kinesiophobia before conducting exercise therapy will be useful for diabetes care.

Keywords: diabetes, fear of movement, kinesiophobia, type 2 diabetes mellitus

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3221 Quantitative Assessment of Different Formulations of Antimalarials in Sentinel Sites of India

Authors: Taruna Katyal Arora, Geeta Kumari, Hari Shankar, Neelima Mishra

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Substandard and counterfeit antimalarials is a major problem in malaria endemic areas. The availability of counterfeit/ substandard medicines is not only decreasing the efficacy in patients, but it is also one of the contributing factors for developing antimalarial drug resistance. Owing to this, a pilot study was conducted to survey quality of drugs collected from different malaria endemic areas of India. Artesunate+Sulphadoxine-Pyrimethamine (AS+SP), Artemether-Lumefantrine (AL), Chloroquine (CQ) tablets were randomly picked from public health facilities in selected states of India. The quality of antimalarial drugs from these areas was assessed by using Global Pharma Health Fund Minilab test kit. This includes physical/visual inspection and disintegration test. Thin-layer chromatography (TLC) was carried out for semi-quantitative assessment of active pharmaceutical ingredients. A total of 45 brands, out of which 21 were for CQ, 14 for AL and 10 for AS+SP were tested from Uttar Pradesh (U.P.), Mizoram, Meghalaya and Gujrat states. One out of 45 samples showed variable disintegration and retension factor. The variable disintegration and retention factor which would have been due to substandard quality or other factors including storage. However, HPLC analysis confirms standard active pharmaceutical ingredient, but may be due to humid temperature and moisture in storage may account for the observed result.

Keywords: antimalarial medicines, counterfeit, substandard, TLC

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3220 Development and Validation of Thermal Stability in Complex System ABDM has two ASIC by NISA and COMSOL Tools

Authors: A. Oukaira, A. Lakhssassi, O. Ettahri

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To make a good thermal management in an ABDM (Adapter Board Detector Module) card, we must first control temperature and its gradient from the first step in the design of integrated circuits ASIC of our complex system. In this paper, our main goal is to develop and validate the thermal stability in order to get an idea of the flow of heat around the ASIC in transient and thus address the thermal issues for integrated circuits at the ABDM card. However, we need heat sources simulations for ABDM card to establish its thermal mapping. This led us to perform simulations at each ASIC that will allow us to understand the thermal ABDM map and find real solutions for each one of our complex system that contains 36 ABDM map, taking into account the different layers around ASIC. To do a transient simulation under NISA, we had to build a function of power modulation in time TIMEAMP. The maximum power generated in the ASIC is 0.6 W. We divided the power uniformly in the volume of the ASIC. This power was applied for 5 seconds to visualize the evolution and distribution of heat around the ASIC. The DBC (Dirichlet Boundary conditions) method was applied around the ABDM at 25°C and just after these simulations in NISA tool we will validate them by COMSOL tool, wich is a numerical calculation software for a modular finite element for modeling a wide variety of physical phenomena characterizing a real problem. It will also be a design tool with its ability to handle 3D geometries for complex systems.

Keywords: ABDM, APD, thermal mapping, complex system

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3219 Controlling Images and Survival Strategies for Muslim Women in Pakistan

Authors: Ayesha Murtza

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Controlling images develop misinformed behaviors about impoverished Muslim Pakistani women that add to the oppression these Pakistani women endure their whole lives. Meanwhile, patriarchal and stereotypical societies provide an ideological justification for gender, class, and racial oppression, especially for women. Cojoining the concepts of controlling images by Patricia Hill Collins (1990) and binary thinking by Barbara Christian (1987), this paper discusses the ways in which various controlling images of urban and rural women are being presented in Pakistani dramas. These images reinforce an interlocking system of oppression for women in Pakistan. This paper further explores how these controlling images of intersecting components like class, gender, religion, ethnicity, physical appearance, color, and caste normalize hegemonic gendered oppression in society and how men have the same attitude towards women of their family whether they belong to the rural or urban class since they are the product of the same society. It further sheds light on how these matrixes of domination are an inevitable part of Pakistani women’s everyday lives and how these women reinforce survival strategies for coping with all these forms of oppression. By employing the feminist interactional framework, this paper elucidates the role of masculinity, femininity, feminist activism, and traditional knowledge against a monolithic image of Pakistani women. By highlighting these, this paper complicates the role of descriptive and visual images, religion, women’s rights, and the stereotypical role of women in Pakistani dramas.

Keywords: controlling images, oppression, women, Pakistan

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3218 Status and Rights of Rohingya Migrants in Bangladesh: A Critical Analysis

Authors: Md Nur Uddin

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The Rohingya people are one of the world's most oppressed and persecuted refugee populations, having been stateless for over six generations and still are. In recent years, more than half-million Rohingya Muslims have fled Myanmar (Burma) for neighboring nations. This article discusses the Status and Rights of Rohingya Migrants in Bangladesh, with a focus on the living conditions of this vulnerable population. A lot of information has been studied about Rohingya refugees states that violence in Rakhine state has sent an estimated 615,500 Rohingya across the border into Bangladesh's Cox's Bazar since August 25, 2017. In Cox's Bazar, a total of 33,131 Rohingya refugees are housed in two registered camps, with an additional 854,024 living in informal settlements nearby. The living conditions of Rohingya refugees in overcrowded camps remain dismal. Mental health is bad, cleanliness is poor, malnutrition is common, and physical and sexual abuse is endemic. A coordinated diplomatic effort involving Bangladesh and Myanmar, as well as international mediators such as the Organization of Islamic Countries and the United Nations, is essential to adequately resolve this complex matter. Bangladeshi officials must ensure the safety of the Rohingyas in the camps and use available humanitarian aid to give the refugees basic amenities such as food, shelter, sanitation, and medical treatment. UNHCR officials should keep an eye on the actual repatriation process to ensure that refugees who have expressed a desire to stay in Bangladesh are not deported against their choice.

Keywords: international refugee laws, united nations, Rohingya, stateless, humanitarian

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3217 The Planning Strategies of Public Sports Facilities Based on the Field Investigation: Case Study of Songyuan, China

Authors: Li Hua Li, Ling Ling Li

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With the National Fitness Program being established as a national strategy by the Chinese government, Chinese old planning strategies of sports facilities which are based on the purpose for hosting high-level sports events have been failed to meet the rapid growth of Chinese residents’ healthy needs. As the most important carrier for promoting the health of citizens in China, public sports facilities may have further conflicts when they are planned without considering the characteristics of the city itself and the fitness needs of the urban residents. With the planning practice in Songyuan in northeastern China, this paper explores the key planning strategies of public sports facilities through the field investigation to obtain the current situation of public sports facilities in Songyuan and the questionnaire to get the date of Songyuan residents’ fitness characteristics and needs. Findings from this investigation suggest that the planning of public sports facilities in Songyuan should first increase the quantities of public sports facilities at the community level, which could match the fitness population and meet the fitness needs in Songyuan. Secondly, the planning should combine with other available resources, such as urban parks, squares and other places where Songyuan residents often choose to do physical activities to enhance the vitality of public sports facilities. Finally, the planning should also link the urban transportation system in Songyuan to improve the accessibility and efficiency of public sports facilities. All these planning strategies could provide essential information for updating the urban and regional design of Songyuan.

Keywords: field investigation, healthy needs, public sports facilities, planning strategies, questionnaire

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3216 Ergosterol Biosynthesis: Non-Conventional Method for Improving Process

Authors: Madalina Postaru, Alexandra Tucaliuc, Dan Cascaval, Anca Irina Galaction

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Ergosterol (ergosta-5,7,22-trien-3β-ol) is the precursor of vitamin D2 (ergocalciferol), known as provitamin D2 as it is converted under UV radiation to this vitamin. The natural sources of ergosterol are mainly the yeasts (Saccharomyces sp., Candida sp.), but it can be also found in fungus (Claviceps sp.) or plants (orchids). As ergosterol is mainly accumulated in yeast cell membranes, especially in free form in the plasma-membrane, and the chemical synthesis of ergosterol does not represent an efficient method for its production, this study aimed to analyze the influence of aeration efficiency on ergosterol production by S. cerevisiae in batch and fed-batch fermentations, by considering different levels of mixing intensity, aeration rate, and n-dodecane concentration. Our previous studies on ergosterol production by S. cerevisiae in batch and fed-batch fermentation systems indicated that the addition of n-dodecane led to the increase of almost 50% of this sterol concentration, the highest productivity being reached for the fed-batch process. The experiments were carried out in a laboratory stirred bioreactor, provided with computer-controlled and recorded parameters. In batch fermentation system, the study indicated that the oxygen mass transfer coefficient, kLa, is amplified for about 3 times by increasing the volumetric concentration of n-dodecane from 0 to 15%. Moreover, the increase of dissolved oxygen concentration by adding n-dodecane leads to the diminution for 3.5 times of the produced alcohol amount. In fed-batch fermentation process, the positive influence of hydrocarbon on oxygen transfer rate is amplified mainly at its higher concentration level, as the result of the increased yeasts cells amount. Thus, by varying n-dodecane concentration from 0 to 15% vol., the kLa value increase becomes more important than for the batch fermentation, being of 4 times

Keywords: ergosterol, yeast fermentation, n-dodecane, oxygen-vector

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3215 A Sustainable Pt/BaCe₁₋ₓ₋ᵧZrₓGdᵧO₃ Catalyst for Dry Reforming of Methane-Derived from Recycled Primary Pt

Authors: Alessio Varotto, Lorenzo Freschi, Umberto Pasqual Laverdura, Anastasia Moschovi, Davide Pumiglia, Iakovos Yakoumis, Marta Feroci, Maria Luisa Grilli

Abstract:

Dry reforming of Methane (DRM) is considered one of the most valuable technologies for green-house gas valorization thanks to the fact that through this reaction, it is possible to obtain syngas, a mixture of H₂ and CO in an H₂/CO ratio suitable for utilization in the Fischer-Tropsch process of high value-added chemicals and fuels. Challenges of the DRM process are the reduction of costs due to the high temperature of the process and the high cost of precious metals of the catalyst, the metal particles sintering, and carbon deposition on the catalysts’ surface. The aim of this study is to demonstrate the feasibility of the synthesis of catalysts using a leachate solution containing Pt coming directly from the recovery of spent diesel oxidation catalysts (DOCs) without further purification. An unusual perovskite support for DRM, the BaCe₁₋ₓ₋ᵧZrₓGdᵧO₃ (BCZG) perovskite, has been chosen as the catalyst support because of its high thermal stability and capability to produce oxygen vacancies, which suppress the carbon deposition and enhance the catalytic activity of the catalyst. BCZG perovskite has been synthesized by a sol-gel modified Pechini process and calcinated in air at 1100 °C. BCZG supports have been impregnated with a Pt-containing leachate solution of DOC, obtained by a mild hydrometallurgical recovery process, as reported elsewhere by some of the authors of this manuscript. For comparison reasons, a synthetic solution obtained by digesting commercial Pt-black powder in aqua regia was used for BCZG support impregnation. Pt nominal content was 2% in both BCZG-based catalysts formed by real and synthetic solutions. The structure and morphology of catalysts were characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Thermogravimetric Analysis (TGA) was used to study the thermal stability of the catalyst’s samples. Brunauer-Emmett-Teller (BET) analysis provided a high surface area of the catalysts. H₂-TPR (Temperature Programmed Reduction) analysis was used to study the consumption of hydrogen for reducibility, and it was associated with H₂-TPD characterization to study the dispersion of Pt on the surface of the support and calculate the number of active sites used by the precious metal. Dry reforming of methane (DRM) reaction, carried out in a fixed bed reactor, showed a high conversion efficiency of CO₂ and CH4. At 850°C, CO₂ and CH₄ conversion were close to 100% for the catalyst obtained with the aqua regia-based solution of commercial Pt-black, and ~70% (for CH₄) and ~80 % (for CO₂) in the case of real HCl-based leachate solution. H₂/CO ratios were ~0.9 and ~0.70 in the first and latter cases, respectively. As far as we know, this is the first pioneering work in which a BCGZ catalyst and a real Pt-containing leachate solution were successfully employed for DRM reaction.

Keywords: dry reforming of methane, perovskite, PGM, recycled Pt, syngas

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3214 Experiences of Students with SLD at University: A Case Study

Authors: Lorna Martha Dreyer

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Consistent with the changing paradigm on the rights of people with disabilities and in pursuit of social justice, there is internationally an increase in students with disabilities enrolling at Higher Education Institutions (HEIs). This trend challenges HEI’s to transform and attain Education for All (EFA) as a global imperative. However, while physical and sensory disabilities are observable, students with specific learning disabilities (SLD) do not present with any visible indications and are often referred to as “hidden” or “invisible” disabilities. This qualitative case study aimed to illuminate the experiences of students with SLDs at a South African university. The research was, therefore, guided by Vygotsky’s social-cultural theory (SCT). This research was conducted within a basic qualitative research methodology embedded in an interpretive paradigm. Data was collected through an online background survey and semi-structured interviews. Thematic qualitative content analysis was used to analyse the collected data systematically. From a social justice perspective, the major findings suggest that there are several factors that impede equal education for students with SLDs at university. Most participants in this small-scale study experienced a lack of acknowledgment and support from lecturers. They reported valuing the support of family and friends more than that of lecturers. It is concluded that lecturers need to be reflective of their pedagogical practices if authentic inclusion is to be realised.

Keywords: higher education, inclusive education, pedagogy, social-cultural theory, specific learning disabilities

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3213 Statistical Analysis Approach for the e-Glassy Mortar And Radiation Shielding Behaviors Using Anova

Authors: Abadou Yacine, Faid Hayette

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Significant investigations were performed on the use and impact on physical properties along with the mechanical strength of the recycled and reused E-glass waste powder. However, it has been modelled how recycled display e-waste glass may affect the characteristics and qualities of dune sand mortar. To be involved in this field, an investigation has been done with the substitution of dune sand for recycled E-glass waste and constant water-cement ratios. The linear relationship between the dune sand mortar and E-glass mortar mix % contributes to the model's reliability. The experimental data was exposed to regression analysis using JMP Statistics software. The regression model with one predictor presented the general form of the equation for the prediction of the five properties' characteristics of dune sand mortar from the substitution ratio of E-waste glass and curing age. The results illustrate that curing a long-term process produced an E-glass waste mortar specimen with the highest compressive strength of 68 MPa in the laboratory environment. Anova analysis indicated that the curing at long-term has the utmost importance on the sorptivity level and ultrasonic pulse velocity loss. Furthermore, the E-glass waste powder percentage has the utmost importance on the compressive strength and improvement in dynamic elasticity modulus. Besides, a significant enhancement of radiation-shielding applications.

Keywords: ANOVA analysis, E-glass waste, durability and sustainability, radiation-shielding

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3212 High Aspect Ratio Micropillar Array Based Microfluidic Viscometer

Authors: Ahmet Erten, Adil Mustafa, Ayşenur Eser, Özlem Yalçın

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We present a new viscometer based on a microfluidic chip with elastic high aspect ratio micropillar arrays. The displacement of pillar tips in flow direction can be used to analyze viscosity of liquid. In our work, Computational Fluid Dynamics (CFD) is used to analyze pillar displacement of various micropillar array configurations in flow direction at different viscosities. Following CFD optimization, micro-CNC based rapid prototyping is used to fabricate molds for microfluidic chips. Microfluidic chips are fabricated out of polydimethylsiloxane (PDMS) using soft lithography methods with molds machined out of aluminum. Tip displacements of micropillar array (300 µm in diameter and 1400 µm in height) in flow direction are recorded using a microscope mounted camera, and the displacements are analyzed using image processing with an algorithm written in MATLAB. Experiments are performed with water-glycerol solutions mixed at 4 different ratios to attain 1 cP, 5 cP, 10 cP and 15 cP viscosities at room temperature. The prepared solutions are injected into the microfluidic chips using a syringe pump at flow rates from 10-100 mL / hr and the displacement versus flow rate is plotted for different viscosities. A displacement of around 1.5 µm was observed for 15 cP solution at 60 mL / hr while only a 1 µm displacement was observed for 10 cP solution. The presented viscometer design optimization is still in progress for better sensitivity and accuracy. Our microfluidic viscometer platform has potential for tailor made microfluidic chips to enable real time observation and control of viscosity changes in biological or chemical reactions.

Keywords: Computational Fluid Dynamics (CFD), high aspect ratio, micropillar array, viscometer

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3211 Protein Extraction by Enzyme-Assisted Extraction followed by Alkaline Extraction from Red Seaweed Eucheuma denticulatum (Spinosum) Used in Carrageenan Production

Authors: Alireza Naseri, Susan L. Holdt, Charlotte Jacobsen

Abstract:

In 2014, the global amount of carrageenan production was 60,000 ton with a value of US$ 626 million. From this number, it can be estimated that the total dried seaweed consumption for this production was at least 300,000 ton/year. The protein content of these types of seaweed is 5 – 25%. If just half of this total amount of protein could be extracted, 18,000 ton/year of a high-value protein product would be obtained. The overall aim of this study was to develop a technology that will ensure further utilization of the seaweed that is used only as raw materials for carrageenan production as single extraction at present. More specifically, proteins should be extracted from the seaweed either before or after extraction of carrageenan with focus on maintaining the quality of carrageenan as a main product. Different mechanical, chemical and enzymatic technologies were evaluated. The optimized process was implemented in lab scale and based on its results; the new experiments were done a pilot and larger scale. In order to calculate the efficiency of the new upstream multi-extraction process, protein content was tested before and after extraction. After this step, the extraction of carrageenan was done and carrageenan content and the effect of extraction on yield were evaluated. The functionality and quality of carrageenan were measured based on rheological parameters. The results showed that by using the new multi-extraction process (submitted patent); it is possible to extract almost 50% of total protein without any negative impact on the carrageenan quality. Moreover, compared to the routine carrageenan extraction process, the new multi-extraction process could increase the yield of carrageenan and the rheological properties such as gel strength in the final carrageenan had a promising improvement. The extracted protein has initially been screened as a plant protein source in typical food applications. Further work will be carried out in order to improve properties such as color, solubility, and taste.

Keywords: carrageenan, extraction, protein, seaweed

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3210 Resilience in Refuge Context: The Validity Assessment Using Child and Youth Resilience Measure-28 among Afghan Young Immigrants in Iran

Authors: Baqir Rezai, Leila Heydarinasab, Rasol Roshan, Mohammad Ghulami

Abstract:

Introduction: The resilience process is one of the controversial and important subjects for child and youth immigrants throughout the world. Positive adaptation to the environment is a consequence of resilience which can affect the quality of life and physical and mental health among immigrants. Objective: A total of 714 Afghan young immigrants (14 to 18-years-old) who live in Iran for more than three years were entered into the study. A random sampling method was applied to obtain data. The study samples were divided into two groups (N1 =360 and N2=354) for exploratory and confirmation analysis. Exploratory factorial analysis was applied to confirm the construct validity of CYRM-28. Results: The results showed that this scale has useful validity content, and the study samples include three factors of individuals, context, and relational in child and youth resilience measure-28. However, from a total of 28 main items, only 15 items could identify these factors. Discussion: The resilience process among young immigrants is mainly explained by individuals, social and cultural conditions. For instance, young immigrants search the resilience process in conditions that caused their immigration. In this context, some questions about the content of security and personal promotion in society could identify three main factors.

Keywords: CYRM-28, factorial analysis, resilience, Afghan young immigrants

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3209 Comparison of Acetylcholinesterase Reactivators Cytotoxicity with Their Structure

Authors: Lubica Muckova, Petr Jost, Jaroslav Pejchal, Daniel Jun

Abstract:

The development of acetylcholinesterase reactivators, i.e. antidotes against organophosphorus poisoning, is an important goal of defence research. The aim of this study was to compare cytotoxicity and chemical structure of 5 currently available (pralidoxime, trimedoxime, obidoxime, methoxime, and asoxime) and 4 newly developed compounds (K027, K074, K075, and K203). In oximes, there could be at least four important structural factors affecting their toxicity, including the number of oxime groups in the molecule, the position of oxime group(s) on pyridinium ring, the length of carbon linker, and the substitution by oxygen or insertion of the double bond into the connection chain. The cytotoxicity of tested substances was measured using colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay (MTT assay) in SH-SY5Y cell line. Toxicity was expressed as toxicological index IC₅₀. The tested compounds showed different cytotoxicity ranging from 1.5 to 27 mM. K027 was the least, and methoxime was the most toxic reactivator. The lowest toxicity was found in a monopyridinium reactivator and bispyridinium reactivators with simple 3C carbon linker. Shortening of connection chain length to 1C, incorporation of oxygen moiety into 3C compounds, elongation of carbon linker to 4C and insertion of a double bond into 4C substances increase AChE reactivators' cytotoxicity. Acknowledgements: This work was supported by a long-term organization development plan Medical Aspects of Weapons of Mass Destruction of the Faculty of Military Health Sciences, University of Defence.

Keywords: acetylcholinesterase, cytotoxicity, organophosphorus poisoning, reactivators of acetylcholinesterase

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3208 Redeeming the Self-Settling Scores with the Nazis by the Means of Poetics

Authors: Liliane Steiner

Abstract:

Beyond the testimonial act, that sheds light on the feminine experience in the Holocaust, the survivors' writing voices first and foremost the abjection of the feminine self brutally inflicted by the Nazis in the Holocaust, and in the same movement redeems the self by the means of poetics, and brings it to an existential state of being a subject. This study aims to stress the poetics of this writing in order to promote the Holocaust literature from the margins to the mainstream and to contribute to the commemoration of the Holocaust in the next generations. Methodology: The study of the survivors' redeeming of self is based on Julia Kristeva's theory of the abject: the self-throws out everything that threatens its existence and Liliane Steiner's theory of the post- abjection of hell: the belated act of vomiting the abject experiences settles cores with the author of the abject to redeem the self. The research will focus on Ruth Sender's trilogy The Cage, To Life and The Holocaust Lady as a case study. Findings: The binary mode that characterizes this writing reflects the experience of Jewish women, who were subject(s), were treated violently as object(s), debased, defeminized and, eventually turned into abject by the Nazis. In a tour de force, this writing re-enacts the postponed resistance, that vomited the abject imposed on the feminine self by the very act of narration, which denounces the real abject, the perpetrators. The post-abjection of self is acted out in constructs of abject, relating the abject experience of the Holocaust as well as the rehabilitation of the surviving self (subject). The transcription of abject surfaces in deconstructing the abject through self- characterization, and in the elusive rendering of bad memories, having recourse to literary figures. The narrative 'I' selects, obstructs, mends and tells the past events from an active standpoint, as would a subject in control of its (narrative) fate. In a compensatory movement, the narrating I tells itself by reconstructing the subject and proving time and again that I is other. Moreover, in the belated endeavor to revenge, testify and narrate the abject, the narrative I defies itself, and represents itself as a dialectical I, splitting and multiplying itself in a deconstructing way. The dialectical I is never (one) I. It voices not only the unvoiced but also and mainly the other silenced 'I's. Drawing its nature and construct from traumatic memories, the dialectical I transgresses boundaries to narrate her story, and in the same breath, the story of Jewish women doomed to silence. In this narrative feat, the dialectical I stresses its essential dialectical existence with the past, never to be (one) again. Conclusion: The pattern of I is other generates patterns of subject(s) that defy, transgress and repudiate the abject and its repercussions on the feminine I. The feminine I writes itself as a survivor that defies the abject (Nazis) and takes revenge. The paradigm of metamorphosis that accompanies the journey of the Holocaust memoirist engenders life and surviving as well as a narration that defies stagnation and death.

Keywords: abject, feminine writing, holocaust, post-abjection

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3207 Thermal and Radon-222 Appraisal in Geothermal Aquifer System, Southeastern Tunisia

Authors: Agoubi Belgacem, Adel Kharroubi

Abstract:

Geothermal groundwater is the main water source to supply various sectors in El Hamma city, southeastern Tunisia. This region was long the destination of thousands of people from Tunisia and neighboring countries for care and bathing. The main objective of this study is to understand the groundwater mineralization origins and factors that control. The second goal is the appraisal of radon in geothermal groundwater in the study area. For this aim, geothermal groundwater was sampled and collected from different locations (thermal baths and deep wells). Physical parameters were measured and major ions were analyzed. Results reveal three water types. The water first type has Na-Mg-Ca-SO4-Cl facies and T>55°C. The second water type dominated by Na-Ca-Cl-SO4 facies with a temperature < 45 °C. However the third water type is dominated by Ca-SO4-Na-Cl-Mg. The three water types may be controlled by depth and geology. The first represent groundwater from deep aquifer (lower cretaceous), the second type was the shallow aquifer and the first is mixed water from deep and shallow water with a temperature ranging from 45 to 55°C. Measured Radon shows that shallow aquifer has a higher 222Rn concentration (677 to 2903 Bq.m-3) than deep water (203 to 1100 Bq.m-3). R-222 in El Hamma thermal aquifer was controlled by structures, porosity and permeability of aquifers. Geostatistical analyses of hydrogeological data and radon activities confirm the vertical flow and communication between deep and shallow aquifers through vertical faults system.

Keywords: Radon-222, geothermal, water, environment, Tunisia

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3206 Theoretical Performance of a Sustainable Clean Energy On-Site Generation Device to Convert Consumers into Producers and Its Possible Impact on Electrical National Grids

Authors: Eudes Vera

Abstract:

In this paper, a theoretical evaluation is carried out of the performance of a forthcoming fuel-less clean energy generation device, the Air Motor. The underlying physical principles that support this technology are succinctly described. Examples of the machine and theoretical values of input and output powers are also given. In addition, its main features like portability, on-site energy generation and delivery, miniaturization of generation plants, efficiency, and scaling down of the whole electric infrastructure are discussed. The main component of the Air Motor, the Thermal Air Turbine, generates useful power by converting in mechanical energy part of the thermal energy contained in a fan-produced airflow while leaving intact its kinetic energy. Due to this fact an air motor can contain a long succession of identical air turbines and the total power generated out of a single airflow can be very large, as well as its mechanical efficiency. It is found using the corresponding formulae that the mechanical efficiency of this device can be much greater than 100%, while its thermal efficiency is always less than 100%. On account of its multiple advantages, the Air Motor seems to be the perfect device to convert energy consumers into energy producers worldwide. If so, it would appear that current national electrical grids would no longer be necessary, because it does not seem practical or economical to bring the energy from far-away distances while it can be generated and consumed locally at the consumer’s premises using just the thermal energy contained in the ambient air.

Keywords: electrical grid, clean energy, renewable energy, in situ generation and delivery, generation efficiency

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3205 Sociodemographic Approach to Juveniles Directed to Delinquent Behaviour in Zonguldak

Authors: Riza Yilmaz, Samet Kiyak, Sezin Nur Yilmaz, Yasemin Yilmaz

Abstract:

Child delinquency has been increasing in our country as well as in many countries of the world. Child intelligence, abilities, family's social environment and life conditions are the factors which affect the child delinquency. The reports of 73 cases ages of 12-15 which were sent to the University of Bulent Ecevit, School of Medicine, Forensic Medicine Department between January 2011-September 2015, in order to evaluate medically, children pushed to crime by the judicial authorities are examined in terms of age, gender, educational background, place of residence, reasons for being sent, whether it’s a repeating crime or not, type of intelligence test, results revealed by forensic medicine and department of mental and neurological disorders. When children pushed to crime examined in terms of their crimes, the most common type of crime was identified as theft (n = 24). The crimes with 19 physical attacks and 12 sexual abuse were seen. Following that other 12 crimes were determined as damage to property, hemp crop, insult, incitement to crime, forgery of private documents, illegal excavation, threatening, involuntary manslaughter. The alleged crimes in 6 cases were more than one. The children pushed to crime are one of the major social problems of many countries. In this sense, it is not only the responsibility of government agencies to protect children pushed to crime, also, the civil society organizations should take place in this struggle.

Keywords: delinquent behaviour, forensic medicine, crime, punishment

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3204 Simultaneous Optimization of Design and Maintenance through a Hybrid Process Using Genetic Algorithms

Authors: O. Adjoul, A. Feugier, K. Benfriha, A. Aoussat

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In general, issues related to design and maintenance are considered in an independent manner. However, the decisions made in these two sets influence each other. The design for maintenance is considered an opportunity to optimize the life cycle cost of a product, particularly in the nuclear or aeronautical field, where maintenance expenses represent more than 60% of life cycle costs. The design of large-scale systems starts with product architecture, a choice of components in terms of cost, reliability, weight and other attributes, corresponding to the specifications. On the other hand, the design must take into account maintenance by improving, in particular, real-time monitoring of equipment through the integration of new technologies such as connected sensors and intelligent actuators. We noticed that different approaches used in the Design For Maintenance (DFM) methods are limited to the simultaneous characterization of the reliability and maintainability of a multi-component system. This article proposes a method of DFM that assists designers to propose dynamic maintenance for multi-component industrial systems. The term "dynamic" refers to the ability to integrate available monitoring data to adapt the maintenance decision in real time. The goal is to maximize the availability of the system at a given life cycle cost. This paper presents an approach for simultaneous optimization of the design and maintenance of multi-component systems. Here the design is characterized by four decision variables for each component (reliability level, maintainability level, redundancy level, and level of monitoring data). The maintenance is characterized by two decision variables (the dates of the maintenance stops and the maintenance operations to be performed on the system during these stops). The DFM model helps the designers choose technical solutions for the large-scale industrial products. Large-scale refers to the complex multi-component industrial systems and long life-cycle, such as trains, aircraft, etc. The method is based on a two-level hybrid algorithm for simultaneous optimization of design and maintenance, using genetic algorithms. The first level is to select a design solution for a given system that considers the life cycle cost and the reliability. The second level consists of determining a dynamic and optimal maintenance plan to be deployed for a design solution. This level is based on the Maintenance Free Operating Period (MFOP) concept, which takes into account the decision criteria such as, total reliability, maintenance cost and maintenance time. Depending on the life cycle duration, the desired availability, and the desired business model (sales or rental), this tool provides visibility of overall costs and optimal product architecture.

Keywords: availability, design for maintenance (DFM), dynamic maintenance, life cycle cost (LCC), maintenance free operating period (MFOP), simultaneous optimization

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3203 Correlation of Residential Community Layout and Neighborhood Relationship: A Morphological Analysis of Tainan Using Space Syntax

Authors: Ping-Hung Chen, Han-Liang Lin

Abstract:

Taiwan has formed diverse settlement patterns in different time and space backgrounds. Various socio-network links are created between individuals, families, communities, and societies, and different living cultures are also derived. But rapid urbanization and social structural change have caused the creation of densely-packed assembly housing complexes and made neighborhood community upward developed. This, among others, seemed to have affected neighborhood relationship and also created social problems. To understand the complex relations and socio-spatial structure of the community, it is important to use mixed methods. This research employs the theory of space syntax to analyze the layout and structural indicators of the selected communities in Tainan city. On the other hand, this research does the survey about residents' interactions and the sense of community by questionnaire of the selected communities. Then the mean values of the syntax measures from each community were correlated with the results of the questionnaire using a Pearson correlation to examine how elements in physical design affect the sense of community and neighborhood relationship. In Taiwan, most urban morphology research methods are qualitative study. This paper tries to use space syntax to find out the correlation between the community layout and the neighborhood relationship. The result of this study could be used in future studies or improve the quality of residential communities in Taiwan.

Keywords: community layout, neighborhood relationship, space syntax, mixed-method

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3202 Air–Water Two-Phase Flow Patterns in PEMFC Microchannels

Authors: Ibrahim Rassoul, A. Serir, E-K. Si Ahmed, J. Legrand

Abstract:

The acronym PEM refers to Proton Exchange Membrane or alternatively Polymer Electrolyte Membrane. Due to its high efficiency, low operating temperature (30–80 °C), and rapid evolution over the past decade, PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause “flooding” (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The experimental transparent fuel cell used in this work was designed to represent actual full scale of fuel cell geometry. According to the operating conditions, a number of flow regimes may appear in the microchannel: droplet flow, blockage water liquid bridge /plug (concave and convex forms), slug/plug flow and film flow. Some of flow patterns are new, while others have been already observed in PEMFC microchannels. An algorithm in MATLAB was developed to automatically determine the flow structure (e.g. slug, droplet, plug, and film) of detected liquid water in the test microchannels and yield information pertaining to the distribution of water among the different flow structures. A video processing algorithm was developed to automatically detect dynamic and static liquid water present in the gas channels and generate relevant quantitative information. The potential benefit of this software allows the user to obtain a more precise and systematic way to obtain measurements from images of small objects. The void fractions are also determined based on images analysis. The aim of this work is to provide a comprehensive characterization of two-phase flow in an operating fuel cell which can be used towards the optimization of water management and informs design guidelines for gas delivery microchannels for fuel cells and its essential in the design and control of diverse applications. The approach will combine numerical modeling with experimental visualization and measurements.

Keywords: polymer electrolyte fuel cell, air-water two phase flow, gas diffusion layer, microchannels, advancing contact angle, receding contact angle, void fraction, surface tension, image processing

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3201 Rheological Evaluation of a Mucoadhesive Precursor of Based-Poloxamer 407 or Polyethylenimine Liquid Crystal System for Buccal Administration

Authors: Jéssica Bernegossi, Lívia Nordi Dovigo, Marlus Chorilli

Abstract:

Mucoadhesive liquid crystalline systems are emerging how delivery systems for oral cavity. These systems are interesting since they facilitate the targeting of medicines and change the release enabling a reduction in the number of applications made by the patient. The buccal mucosa is permeable besides present a great blood supply and absence of first pass metabolism, it is a good route of administration. It was developed two systems liquid crystals utilizing as surfactant the ethyl alcohol ethoxylated and propoxylated (30%) as oil phase the oleic acid (60%), and the aqueous phase (10%) dispersion of polymer polyethylenimine (0.5%) or dispersion of polymer poloxamer 407 (16%), with the intention of applying the buccal mucosa. Initially, was performed for characterization of systems the conference by polarized light microscopy and rheological analysis. For the preparation of the systems the components described was added above in glass vials and shaken. Then, 30 and 100% artificial saliva were added to each prepared formulation so as to simulate the environment of the oral cavity. For the verification of the system structure, aliquots of the formulations were observed in glass slide and covered with a coverslip, examined in polarized light microscope (PLM) Axioskop - Zeizz® in 40x magnifier. The formulations were also evaluated for their rheological profile Rheometer TA Instruments®, which were obtained rheograms the selected systems employing fluency mode (flow) in temperature of 37ºC (98.6ºF). In PLM, it was observed that in formulations containing polyethylenimine and poloxamer 407 without the addition of artificial saliva was observed dark-field being indicative of microemulsion, this was also observed with the formulation that was increased with 30% of the artificial saliva. In the formulation that was increased with 100% simulated saliva was shown to be a system structure since it presented anisotropy with the presence of striae being indicative of hexagonal liquid crystalline mesophase system. Upon observation of rheograms, both systems without the addition of artificial saliva showed a Newtonian profile, after addition of 30% artificial saliva have been given a non-Newtonian behavior of the pseudoplastic-thixotropic type and after adding 100% of the saliva artificial proved plastic-thixotropic. Furthermore, it is clearly seen that the formulations containing poloxamer 407 have significantly larger (15-800 Pa) shear stress compared to those containing polyethyleneimine (5-50 Pa), indicating a greater plasticity of these. Thus, it is possible to observe that the addition of saliva was of interest to the system structure, starting from a microemulsion for a liquid crystal system, thereby also changing thereby its rheological behavior. The systems have promising characteristics as controlled release systems to the oral cavity, as it features good fluidity during its possible application and greater structuring of the system when it comes into contact with environmental saliva.

Keywords: liquid crystal system, poloxamer 407, polyethylenimine, rheology

Procedia PDF Downloads 447