Search results for: Hilal Acar
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 55

Search results for: Hilal Acar

25 Mathematical Modelling of Ultrasound Pre-Treatment in Microwave Dried Strawberry (Fragaria L.) Slices

Authors: Hilal Uslu, Salih Eroglu, Betul Ozkan, Ozcan Bulantekin, Alper Kuscu

Abstract:

In this study, the strawberry (Fragaria L.) fruits, which were pretreated with ultrasound (US), were worked on in the microwave by using 90W power. Then mathematical modelling was applied to dried fruits by using different experimental thin layer models. The sliced fruits were subjected to ultrasound treatment at a frequency of 40 kHz for 10, 20, and 30 minutes, in an ultrasonic water bath, with a ratio of 1:4 to fruit/water. They are then dried in the microwave (90W). The drying process continued until the product moisture was below 10%. By analyzing the moisture change of the products at a certain time, eight different thin-layer drying models, (Newton, page, modified page, Midilli, Henderson and Pabis, logarithmic, two-term, Wang and Singh) were tested for verification of experimental data. MATLAB R2015a statistical program was used for the modelling, and the best suitable model was determined with R²adj (coefficient of determination of compatibility), and root mean square error (RMSE) values. According to analysis, the drying model that best describes the drying behavior for both drying conditions was determined as the Midilli model by high R²adj and low RMSE values. Control, 10, 20, and 30 min US for groups R²adj and RMSE values was established as respectively; 0,9997- 0,005298; 0,9998- 0,004735; 0,9995- 0,007031; 0,9917-0,02773. In addition, effective diffusion coefficients were calculated for each group and were determined as 3,80x 10⁻⁸, 3,71 x 10⁻⁸, 3,26 x10⁻⁸ ve 3,5 x 10⁻⁸ m/s, respectively.

Keywords: mathematical modelling, microwave drying, strawberry, ultrasound

Procedia PDF Downloads 125
24 Hybrid Thresholding Lifting Dual Tree Complex Wavelet Transform with Wiener Filter for Quality Assurance of Medical Image

Authors: Hilal Naimi, Amelbahahouda Adamou-Mitiche, Lahcene Mitiche

Abstract:

The main problem in the area of medical imaging has been image denoising. The most defying for image denoising is to secure data carrying structures like surfaces and edges in order to achieve good visual quality. Different algorithms with different denoising performances have been proposed in previous decades. More recently, models focused on deep learning have shown a great promise to outperform all traditional approaches. However, these techniques are limited to the necessity of large sample size training and high computational costs. This research proposes a denoising approach basing on LDTCWT (Lifting Dual Tree Complex Wavelet Transform) using Hybrid Thresholding with Wiener filter to enhance the quality image. This research describes the LDTCWT as a type of lifting wavelets remodeling that produce complex coefficients by employing a dual tree of lifting wavelets filters to get its real part and imaginary part. Permits the remodel to produce approximate shift invariance, directionally selective filters and reduces the computation time (properties lacking within the classical wavelets transform). To develop this approach, a hybrid thresholding function is modeled by integrating the Wiener filter into the thresholding function.

Keywords: lifting wavelet transform, image denoising, dual tree complex wavelet transform, wavelet shrinkage, wiener filter

Procedia PDF Downloads 131
23 Conjugated Linoleic Acid (CLA) Health Benefits and Sources

Authors: Hilal Ahmad Punoo

Abstract:

Conjugated linoleic acid (CLA) is a mixture of positional and geometric isomers of octadecadienoic acid with two conjugated double bonds. Of more than a dozen isomers of CLA found naturally in dairy and meat products from ruminants, c-9, t-11 and t-10, c-12 are the two isomers with known physiological importance, including anticarcinogenic, antidiabetic, antilipogenic, and antiatherosclerotic effects. Conjugated linoleic acids (CLA) may influence the onset and severity of several chronic diseases, including various cancers, atherosclerosis, obesity, bone density loss, and diabetes. These findings are of special interest to the agriculture community, because dietary sources of CLA are almost exclusively beef and dairy products. Thus, a better understanding of the specific isomers and mechanisms responsible for these positive effects of CLA on human health would be both prudent and economically beneficial. To date, research related to the advantages of CLA consumption on human health has been conducted using experimental laboratory animals and cell culture systems. These data consistently show that relatively low levels of CLA can influence risk of cancer. Further, very recent investigations suggest that the predominate CLA isoform (cis-9, trans-11 CLA or rumenic acid) found in beef and milk fat possesses anticarcinogenic effects but does not alter body composition; the trans-10, cis-12 CLA has been shown to inhibit lipogenesis. Clearly, further work, especially using human subjects, will be required to characterize the potential benefits of CLA consumption on human health. Moreover, we suggest that foods naturally containing high amounts of CLA (e.g., beef and dairy products) be considered as meeting the definition of functional foods.

Keywords: conjugated linoleic acid, potential health benefits, fats, animals, humans

Procedia PDF Downloads 284
22 Discussing the Values of Collective Memory and Cultural / Rural Landscape Based on the Concept of Eco-Village; Case of Turkey, Gölpazarı, Kurşunlu Village

Authors: Parisa Göker, Hilal Kahveci, Özlem Candan Hergül

Abstract:

Humans are generating culture while being in touch with nature. Along with skills, local knowledge based on experience, and many other subjects developed within this process, 'culture' offers humans a chance to survive. For this reason, culture forms the equipment for humans, which facilitates their survival in all ecosystems. Together with technology, quick consumption of natural sources and overuse culture of humans have brought up the eco-village concept. Ecovillages are ecologically, economically, socio-culturally, and spiritually sustainable settlement models. It is known that the eco-village approach is applying a proper methodology on behalf of integrative and versatile solution generation. Today, the eco-village approach, introducing a radical criticism to the understanding of civilization and consumption culture and deeming urban solutions inadequate as a spatial reflection to civilization and consumption culture, while making a difference about integrative solution offering with multidimensional features, along with the goal of creating self-sufficient communities, is creating solutions on the subject of both reducing the ecological footprint of humans and to provide social order and also to solve the injustice seen in terms of income and life standards. In this study, environmental issues, sustainable development, and environmental sustainability topics are examined within the context of eco-tourism and eco-village. Alongside this, the natural and cultural landscape values of Kurşunlu village which are located in Bilecik province’s Gölpazarı county, and a contextual frame is created for the facilitation of sustainability in the event of dynamizing the Kurşunlu village in terms of tourism-oriented activities.

Keywords: eco village, sustainability, rural landscape, cultural landscape

Procedia PDF Downloads 114
21 Enhancing Warehousing Operation In Cold Supply Chain Through The Use Of IOT And Lifi Technologies

Authors: Sarah El-Gamal, Passent Hossam, Ahmed Abd El Aziz, Rojina Mahmoud, Ahmed Hassan, Dalia Hilal, Eman Ayman, Hana Haytham, Omar Khamis

Abstract:

Several concerns fall upon the supply chain, especially the cold supply chain. According to the literature, the main challenges in the cold supply chain are the distribution and storage phases. In this research, researchers focused on the storage area, which contains several activities such as the picking activity that faces a lot of obstacles and challenges The implementation of IoT solutions enables businesses to monitor the temperature of food items, which is perhaps the most critical parameter in cold chains. Therefore, researchers proposed a practical solution that would help in eliminating the problems related to ineffective picking for products, especially fish and seafood products, by using IoT technology, most notably LiFi technology. Thus, guaranteeing sufficient picking, reducing waste, and consequently lowering costs. A prototype was specially designed and examined. This research is a single case study research. Two methods of data collection were used; observation and semi-structured interviews. Semi-structured interviews were conducted with managers and decision maker at Carrefour Alexandria to validate the problem and the proposed practical solution using IoTandLiFi technology. A total of three interviews were conducted. As a result, a SWOT analysis was achieved in order to highlight all the strengths and weaknesses of using the recommended Lifi solution in the picking process. According to the investigations, it was found that the use of IoT and LiFi technology is cost effective, efficient, and reduces human errors, minimize the percentage of product waste and thus save money and cost. Thus, increasing customer satisfaction and profits gained.

Keywords: cold supply chain, picking process, temperature control, IOT, warehousing, LIFI

Procedia PDF Downloads 147
20 Coronary Artery Calcium Score and Statin Treatment Effect on Myocardial Infarction and Major Adverse Cardiovascular Event of Atherosclerotic Cardiovascular Disease: A Systematic Review and Meta-Analysis

Authors: Yusra Pintaningrum, Ilma Fahira Basyir, Sony Hilal Wicaksono, Vito A. Damay

Abstract:

Background: Coronary artery calcium (CAC) scores play an important role in improving prognostic accuracy and can be selectively used to guide the allocation of statin therapy for atherosclerotic cardiovascular disease outcomes and potentially associated with the occurrence of MACE (Major Adverse Cardiovascular Event) and MI (Myocardial Infarction). Objective: This systematic review and meta-analysis aim to analyze the findings of a study about CAC Score and statin treatment effect on MI and MACE risk. Methods: Search for published scientific articles using the PRISMA (Preferred Reporting, Items for Systematic Reviews and Meta-Analysis) method conducted on PubMed, Cochrane Library, and Medline databases published in the last 20 years on “coronary artery calcium” AND “statin” AND “cardiovascular disease” Further systematic review and meta-analysis using RevMan version 5.4 were performed based on the included published scientific articles. Results: Based on 11 studies included with a total of 1055 participants, we performed a meta-analysis and found that individuals with CAC score > 0 increased risk ratio of MI 8.48 (RR = 9.48: 95% CI: 6.22 – 14.45) times and MACE 2.48 (RR = 3.48: 95% CI: 2.98 – 4.05) times higher than CAC score 0 individual. Statin compared against non-statin treatment showed a statistically insignificant overall effect on the risk of MI (P = 0.81) and MACE (P = 0.89) in an individual with elevated CAC score 1 – 100 (P = 0.65) and > 100 (P = 0.11). Conclusions: This study found that an elevated CAC scores individual has a higher risk of MI and MACE than a non-elevated CAC score individual. There is no significant effect of statin compared against non-statin treatment to reduce MI and MACE in elevated CAC score individuals of 1 – 100 or > 100.

Keywords: coronary artery calcium, statin, cardiovascular disease, myocardial infarction, MACE

Procedia PDF Downloads 66
19 Investigating the Dynamic Plantar Pressure Distribution in Individuals with Multiple Sclerosis

Authors: Hilal Keklicek, Baris Cetin, Yeliz Salci, Ayla Fil, Umut Altinkaynak, Kadriye Armutlu

Abstract:

Objectives and Goals: Spasticity is a common symptom characterized with a velocity dependent increase in tonic stretch reflexes (muscle tone) in patient with multiple sclerosis (MS). Hypertonic muscles affect the normal plantigrade contact by disturbing accommodation of foot to the ground while walking. It is important to know the differences between healthy and neurologic foot features for management of spasticity related deformities and/or determination of rehabilitation purposes and contents. This study was planned with the aim of investigating the dynamic plantar pressure distribution in individuals with MS and determining the differences between healthy individuals (HI). Methods: Fifty-five individuals with MS (108 foot with spasticity according to Modified Ashworth Scale) and 20 HI (40 foot) were the participants of the study. The dynamic pedobarograph was utilized for evaluation of dynamic loading parameters. Participants were informed to walk at their self-selected speed for seven times to eliminate learning effect. The parameters were divided into 2 categories including; maximum loading pressure (N/cm2) and time of maximum pressure (ms) were collected from heal medial, heal lateral, mid foot, heads of first, second, third, fourth and fifth metatarsal bones. Results: There were differences between the groups in maximum loading pressure of heal medial (p < .001), heal lateral (p < .001), midfoot (p=.041) and 5th metatarsal areas (p=.036). Also, there were differences between the groups the time of maximum pressure of all metatarsal areas, midfoot, heal medial and heal lateral (p < .001) in favor of HI. Conclusions: The study provided basic data about foot pressure distribution in individuals with MS. Results of the study primarily showed that spasticity of lower extremity muscle disrupted the posteromedial foot loading. Secondarily, according to the study result, spasticity lead to inappropriate timing during load transfer from hind foot to forefoot.

Keywords: multiple sclerosis, plantar pressure distribution, gait, norm values

Procedia PDF Downloads 294
18 Turkey in Minds: Cognitive and Social Representation of "East" and "West"

Authors: Feyzan Tuzkaya, Nihan S. Soylu, Caglar Solak, Mehmet Peker, Hilal Peker, Kemal Ozeralp, Ceren Mete, Ezgi Mehmetoglu, Mehmet Karasu, Cihan Elci, Ece Akca, Melek Goregenli

Abstract:

Perception, evaluation and representation of the environment have been the subject of many disciplines including psychology, geography and architecture. In environmental and social psychology literature there are several evidences which suggest that cognitive representations about a place consisted of not only geographic items but also social and cultural. Mental representations of residence area or a country is influenced and determined by social-demographics, the physical and social context. Thus, all mental representations of a given place are also social representations. Cognitive maps are the main and common instruments that are used to identify spatial images and the difference between physical and subjective environments. The aim of the current study is investigating the mental and social representations of Turkey in university students’ minds. Data was collected from 249 university students from different departments (i.e. psychology, geography, history, tourism departments) of Ege University. Participants were requested to reflect Turkey in their mind onto the paper drawing sketch maps. According to the results, cognitive maps showed geographic aspects of Turkey as well as the context of symbolic, cultural and political reality of Turkey. That is to say, these maps had many symbolic and verbal items related to critics on social and cultural problems, ongoing ethnic and political conflicts, and actual political agenda of Turkey. Additionally, one of main differentiations in these representations appeared in terms of the East and West side of the Turkey, and the representations of the East and West was varied correspondingly participants’ cultural background, their ethnic values, and where they have born. The results of the study were discussed in environmental and social psychological perspective considering cultural and social values of Turkey and current political circumstances of the country.

Keywords: cognitive maps, East, West, politics, social representations, Turkey

Procedia PDF Downloads 373
17 GIS-Based Identification of Overloaded Distribution Transformers and Calculation of Technical Electric Power Losses

Authors: Awais Ahmed, Javed Iqbal

Abstract:

Pakistan has been for many years facing extreme challenges in energy deficit due to the shortage of power generation compared to increasing demand. A part of this energy deficit is also contributed by the power lost in transmission and distribution network. Unfortunately, distribution companies are not equipped with modern technologies and methods to identify and eliminate these losses. According to estimate, total energy lost in early 2000 was between 20 to 26 percent. To address this issue the present research study was designed with the objectives of developing a standalone GIS application for distribution companies having the capability of loss calculation as well as identification of overloaded transformers. For this purpose, Hilal Road feeder in Faisalabad Electric Supply Company (FESCO) was selected as study area. An extensive GPS survey was conducted to identify each consumer, linking it to the secondary pole of the transformer, geo-referencing equipment and documenting conductor sizes. To identify overloaded transformer, accumulative kWH reading of consumer on transformer was compared with threshold kWH. Technical losses of 11kV and 220V lines were calculated using the data from substation and resistance of the network calculated from the geo-database. To automate the process a standalone GIS application was developed using ArcObjects with engineering analysis capabilities. The application uses GIS database developed for 11kV and 220V lines to display and query spatial data and present results in the form of graphs. The result shows that about 14% of the technical loss on both high tension (HT) and low tension (LT) network while about 4 out of 15 general duty transformers were found overloaded. The study shows that GIS can be a very effective tool for distribution companies in management and planning of their distribution network.

Keywords: geographical information system, GIS, power distribution, distribution transformers, technical losses, GPS, SDSS, spatial decision support system

Procedia PDF Downloads 347
16 Stress Concentration and Strength Prediction of Carbon/Epoxy Composites

Authors: Emre Ozaslan, Bulent Acar, Mehmet Ali Guler

Abstract:

Unidirectional composites are very popular structural materials used in aerospace, marine, energy and automotive industries thanks to their superior material properties. However, the mechanical behavior of composite materials is more complicated than isotropic materials because of their anisotropic nature. Also, a stress concentration availability on the structure, like a hole, makes the problem further complicated. Therefore, enormous number of tests require to understand the mechanical behavior and strength of composites which contain stress concentration. Accurate finite element analysis and analytical models enable to understand mechanical behavior and predict the strength of composites without enormous number of tests which cost serious time and money. In this study, unidirectional Carbon/Epoxy composite specimens with central circular hole were investigated in terms of stress concentration factor and strength prediction. The composite specimens which had different specimen wide (W) to hole diameter (D) ratio were tested to investigate the effect of hole size on the stress concentration and strength. Also, specimens which had same specimen wide to hole diameter ratio, but varied sizes were tested to investigate the size effect. Finite element analysis was performed to determine stress concentration factor for all specimen configurations. For quasi-isotropic laminate, it was found that the stress concentration factor increased approximately %15 with decreasing of W/D ratio from 6 to 3. Point stress criteria (PSC), inherent flaw method and progressive failure analysis were compared in terms of predicting the strength of specimens. All methods could predict the strength of specimens with maximum %8 error. PSC was better than other methods for high values of W/D ratio, however, inherent flaw method was successful for low values of W/D. Also, it is seen that increasing by 4 times of the W/D ratio rises the failure strength of composite specimen as %62.4. For constant W/D ratio specimens, all the strength prediction methods were more successful for smaller size specimens than larger ones. Increasing the specimen width and hole diameter together by 2 times reduces the specimen failure strength as %13.2.

Keywords: failure, strength, stress concentration, unidirectional composites

Procedia PDF Downloads 127
15 A Research Study on Planning of Water-Based Recreation Operation on the Deriner Reservoir and Its Near Around

Authors: Hi̇lal Surat

Abstract:

People who want to get rid of stress and intensive working tempo for a while head for recreation operations in order to get rest and have fun. Therefore, planning recreation operation makes contributions to social, physiological, economic and psychological development of an individual and the community in a way that the needs of people meet regularly and constantly. The rapid increase of world population rate makes necessary of benefit from natural or man-made resources in a multiple way. Dams and reservoirs which are built near urban area with the aim of electrical energy conversion and agricultural irrigation are considered as natural area providing various opportunities such as recreation operations. Dams have a great importance regarding to protection and improvement of water resources and coming into service of community. There should be a priority to protect these water resources, which are essential for nature and living organisms. It should be taken into consideration that these water resources are the most important input in the area and have high nature value to make sustainability of recreation effectiveness. The Deriner reservoir that has been built yet near the province of Artvin with natural and cultural properties is considered as an alternative option for meeting the needs of people for sportive and recreation activities and as a potential for planning of water-based recreation activities. Hence, in this study, activities that meet the expectations of people who get benefit from the area considering to natural, cultural and sportive recreation opportunities will be developed. In the first place, planning criteria for some sportive and water-based recreation operations will be defined in order to use the area for recreation and sportive activities and these criteria will be a base for a macro planning work within the holistic perspective of natural, cultural, and economical structure of the area. After this time, necessities of local people and evaluation of reservoir recreational potential will be determined, end then different socio-economic groups according to their in-come, age groups will be chosen and the questionnaire which has already prepared will be done these groups, as a result of these questionnaire recreational activities in water necessities will determine and we are going to develop different suggestion for this reservoir.

Keywords: dam, dam lakes, Deriner, recreation, water based activities

Procedia PDF Downloads 323
14 Challenges to Quality Primary Health Care in Saudi Arabia and Potential Improvements Implemented by Other Systems

Authors: Hilal Al Shamsi, Abdullah Almutairi

Abstract:

Introduction: As primary healthcare centres play an important role in implementing Saudi Arabia’s health strategy, this paper offers a review of publications on the quality of the country’s primary health care. With the aim of deciding on solutions for improvement, it provides an overview of healthcare quality in this context and indicates barriers to quality. Method: Using two databases, ProQuest and Scopus, data extracted from published articles were systematically analysed for determining the care quality in Saudi primary health centres and obstacles to achieving higher quality. Results: Twenty-six articles met the criteria for inclusion in this review. The components of healthcare quality were examined in terms of the access to and effectiveness of interpersonal and clinical care. Good access and effective care were identified in such areas as maternal health care and the control of epidemic diseases, whereas poor access and effectiveness of care were shown for chronic disease management programmes, referral patterns (in terms of referral letters and feedback reports), health education and interpersonal care (in terms of language barriers). Several factors were identified as barriers to high-quality care. These included problems with evidence-based practice implementation, professional development, the use of referrals to secondary care and organisational culture. Successful improvements have been implemented by other systems, such as mobile medical units, electronic referrals, online translation tools and mobile devices and their applications; these can be implemented in Saudi Arabia for improving the quality of the primary healthcare system in this country. Conclusion: The quality of primary health care in Saudi Arabia varies among the different services. To improve quality, management programmes and organisational culture must be promoted in primary health care. Professional development strategies are also needed for improving the skills and knowledge of healthcare professionals. Potential improvements can be implemented to improve the quality of the primary health system.

Keywords: quality, primary health care, Saudi Arabia, health centres, general medical

Procedia PDF Downloads 163
13 An Evaluation of Medical Waste in Health Facilities through Data Envelopment Analysis (DEA) Method: Turkey-Amasya Public Hospitals Union Model

Authors: Murat Iskender Aktaş, Sadi Ergin, Rasime Acar Aktaş

Abstract:

In the light of fast-paced changes and developments in the health sector, the Ministry of Health started a new structuring with decree law numbered 663 within the scope of the Project of Transformation in Health. Accordingly, hospitals should ensure patient satisfaction through more efficient, more effective use of resources and sustainable finance by placing patients in the centre and should operate to increase efficiency to its maximum level while doing these. Within this study, in order to find out how efficient the hospitals were in terms of medical waste management between the years 2011-2014, the data from six hospitals of Amasya Public Hospitals Union were evaluated separately through Data Envelopment Analysis (DEA) method. First of all, input variables were determined. Input variables were the number of patients admitted to polyclinics, the number of inpatients in clinics, the number of patients who were operated and the number of patients who applied to the laboratory. Output variable was the cost of medical wastes in Turkish liras. Each hospital’s total medical waste level before and after public hospitals union; the amounts of average medical waste per patient admitted to polyclinics, per inpatient in clinics, per patient admitted to laboratory and per operated patient were compared within each group. In addition, average medical waste levels and costs were compared for Turkey in general and Europe in general. Paired samples t-test was used to find out whether the changes (increase-decrease) after public hospitals union were statistically significant. The health facilities that were unsuccessful in terms of medical waste management before and after public hospital union and the factors that caused this failure were determined. Based on the results, for each health facility that was ineffective in terms of medical waste management, the level of improvement required for each input was determined. The results of the study showed that there was an improvement in medical waste management applications after the health facilities became a member of public hospitals union; their medical waste levels were lower than the average of Turkey and Europe while the averages of cost of disposal were the highest.

Keywords: medical waste management, cost of medical waste, public hospitals, data envelopment analysis

Procedia PDF Downloads 389
12 Effect of Proteoliposome Concentration on Salt Rejection Rate of Polysulfone Membrane Prepared by Incorporation of Escherichia coli and Halomonas elongata Aquaporins

Authors: Aysenur Ozturk, Aysen Yildiz, Hilal Yilmaz, Pinar Ergenekon, Melek Ozkan

Abstract:

Water scarcity is one of the most important environmental problems of the World today. Desalination process is regarded as a promising solution to solve drinking water problem of the countries facing with water shortages. Reverse osmosis membranes are widely used for desalination processes. Nano structured biomimetic membrane production is one of the most challenging research subject for improving water filtration efficiency of the membranes and for reducing the cost of desalination processes. There are several researches in the literature on the development of novel biomimetic nanofiltration membranes by incorporation of aquaporin Z molecules. Aquaporins are cell membrane proteins that allow the passage of water molecules and reject all other dissolved solutes. They are present in cell membranes of most of the living organisms and provide high water passage capacity. In this study, GST (Glutathione S-transferas) tagged E. coli aquaporinZ and H. elongate aquaporin proteins, which were previously cloned and characterized, were purified from E. coli BL21 cells and used for fabrication of modified Polysulphone Membrane (PS). Aquaporins were incorporated on the surface of the membrane by using 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) phospolipids as carrier liposomes. Aquaporin containing proteoliposomes were immobilized on the surface of the membrane with m-phenylene-diamine (MPD) and trimesoyl chloride (TMC) rejection layer. Water flux, salt rejection and glucose rejection performances of the thin film composite membranes were tested by using Dead-End Reactor Cell. In this study, effect of proteoliposome concentration, and filtration pressure on water flux and salt rejection rate of membranes were investigated. Type of aquaporin used for membrane fabrication, flux and pressure applied for filtration were found to be important parameters affecting rejection rates. Results suggested that optimization of concentration of aquaporin carriers (proteoliposomes) on the membrane surface is necessary for fabrication of effective composite membranes used for different purposes.

Keywords: aquaporins, biomimmetic membranes, desalination, water treatment

Procedia PDF Downloads 170
11 The Effect of Musical Mobile Usage on the Physiological Parameters and Pain Level During Intestinal Stomaterapy Procedure in Infants

Authors: Hilal Keskin, Gülzade Uysal

Abstract:

This study was conducted to determine the effect of bedside music mobile use on physiological parameters and pain level during intestinal stomaterapy in infants. The study was carried out with 66 babies (music mobile group: 33, Control group: 33) who were followed in the pediatric surgery and urology unit of Kanuni Sultan Süleyman Training and Research Hospital between December 2018- October 2019. Data were collected using the “Data Collection Form” and “FLACC Pain Scale.” They were evaluated using the appropriate statistical methods in the SPSS 22.0 program. The difference between the descriptive features of music mobile and control group was not significant (p> 0.05) groups are distributed homogeneously. When the in-group results were examined; There was no significant change in the mean values of Hearth Peak Beat (HPB), SpO2 and blood pressure of the infants in the music mobile group during stomaterapy (p>0.05). Body temperature and Face, Leg, Activity, Cry, Consolability (FLACC) Pain Scale scores were found to increase immediately after stomaterapy (p<0.05). It was found that the mean scores of KTA, body temperature and FLACC pain of the babies in the control group increased significantly after the stomaterapy and SpO2 value decreased (p <0,05). After 15 minutes from stomatherapy, KTA, blood pressure, body temperature and FLACC pain scores averaged; although SpO2 value increased, it was determined that it could not reach pre-stomaterapy value. Results between groups; KTA, SpO2, systolic/diastolic blood pressure, body temperature, and FLACC pain score mean values between groups were homogeneous before stomaterapy (p> 0.05). In the control group, a significant increase was found in the mean scores of KTA, body temperature and FLACC pain after stomaterapy compared to the bedside music mobile group, and a significant decrease in SpO2 values (p <0.05). In the control group, the mean body temperature and FLACC pain scores of the infants 15 minutes after stomaterapy were significantly increased and the SpO2 values were significantly lower than the bedside music group (p <0.05). According to the results of the research; The use of bedside music mobile during intestinal stomaterapy was found to be effective in decreasing the physiological parameters and pain level. It can be recommended for use in infants during painful interventions.

Keywords: intestinal stomatherapy, infant, musical mobile, pain, physiological parameters

Procedia PDF Downloads 158
10 Investigation of Preschool Children's Mathematics Concept Acquisition in Terms of Different Variables

Authors: Hilal Karakuş, Berrin Akman

Abstract:

Preschool years are considered as critical years because of shaping the future lives of individuals. All of the knowledge, skills, and concepts are acquired during this period. Also, basis of academic skills is based on this period. As all of the developmental areas are the fastest in that period, the basis of mathematics education should be given in this period, too. Mathematics is seen as a difficult and abstract course by the most people. Therefore, the enjoyable side of mathematics should be presented in a concrete way in this period to avoid any bias of children for mathematics. This study is conducted to examine mathematics concept acquisition of children in terms of different variables. Screening model is used in this study which is carried out in a quantity way. The study group of this research consists of total 300 children, selected from each class randomly in groups of five, who are from public and private preschools in Çankaya, which is district of Ankara, in 2014-2015 academic year and attending children in the nursery classes and preschool institutions are connected to the Ministry of National Education. The study group of the research was determined by stage sampling method. The schools, which formed study group, are chosen by easy sampling method and the children are chosen by simple random method. Research data were collected with Bracken Basic Concept Scale–Revised Form and Child’s Personal Information Form generated by the researcher in order to get information about children and their families. Bracken Basic Concept Scale-Revised Form consists of 11 sub-dimensions (color, letter, number, size, shape, comparison, direction-location, and quantity, individual and social awareness, building- material) and 307 items. Subtests related to the mathematics were used in this research. In the “Child Individual Information Form” there are items containing demographic information as followings: age of children, gender of children, attending preschools educational intuitions for children, school attendance, mother’s and father’s education levels. At the result of the study, while it was found that children’s mathematics skills differ from age, state of attending any preschool educational intuitions , time of attending any preschool educational intuitions, level of education of their mothers and their fathers; it was found that it does not differ by the gender and type of school they attend.

Keywords: preschool education, preschool period children, mathematics education, mathematics concept acquisitions

Procedia PDF Downloads 323
9 Dry Modifications of PCL/Chitosan/PCL Tissue Scaffolds

Authors: Ozan Ozkan, Hilal Turkoglu Sasmazel

Abstract:

Natural polymers are widely used in tissue engineering applications, because of their biocompatibility, biodegradability and solubility in the physiological medium. On the other hand, synthetic polymers are also widely utilized in tissue engineering applications, because they carry no risk of infectious diseases and do not cause immune system reaction. However, the disadvantages of both polymer types block their individual usages as tissue scaffolds efficiently. Therefore, the idea of usage of natural and synthetic polymers together as a single 3D hybrid scaffold which has the advantages of both and the disadvantages of none has been entered to the literature. On the other hand, even though these hybrid structures support the cell adhesion and/or proliferation, various surface modification techniques applied to the surfaces of them to create topographical changes on the surfaces and to obtain reactive functional groups required for the immobilization of biomolecules, especially on the surfaces of synthetic polymers in order to improve cell adhesion and proliferation. In a study presented here, to improve the surface functionality and topography of the layer by layer electrospun 3D poly-epsilon-caprolactone/chitosan/poly-epsilon-caprolactone hybrid tissue scaffolds by using atmospheric pressure plasma method, thus to improve cell adhesion and proliferation of these tissue scaffolds were aimed. The formation/creation of the functional hydroxyl and amine groups and topographical changes on the surfaces of scaffolds were realized by using two different atmospheric pressure plasma systems (nozzle type and dielectric barrier discharge (DBD) type) carried out under different gas medium (air, Ar+O2, Ar+N2). The plasma modification time and distance for the nozzle type plasma system as well as the plasma modification time and the gas flow rate for DBD type plasma system were optimized with monitoring the changes in surface hydrophilicity by using contact angle measurements. The topographical and chemical characterizations of these modified biomaterials’ surfaces were carried out with SEM and ESCA, respectively. The results showed that the atmospheric pressure plasma modifications carried out with both nozzle type plasma and DBD plasma caused topographical and functionality changes on the surfaces of the layer by layer electrospun tissue scaffolds. However, the shelf life studies indicated that the hydrophilicity introduced to the surfaces was mainly because of the functionality changes. Therefore, according to the optimized results, samples treated with nozzle type air plasma modification applied for 9 minutes from a distance of 17 cm and Ar+O2 DBD plasma modification applied for 1 minute under 70 cm3/min O2 flow rate were found to have the highest hydrophilicity compared to pristine samples.

Keywords: biomaterial, chitosan, hybrid, plasma

Procedia PDF Downloads 251
8 Comparison of Gait Variability in Individuals with Trans-Tibial and Trans-Femoral Lower Limb Loss: A Pilot Study

Authors: Hilal Keklicek, Fatih Erbahceci, Elif Kirdi, Ali Yalcin, Semra Topuz, Ozlem Ulger, Gul Sener

Abstract:

Objectives and Goals: The stride-to-stride fluctuations in gait is a determinant of qualified locomotion as known as gait variability. Gait variability is an important predictive factor of fall risk and useful for monitoring the effects of therapeutic interventions and rehabilitation. Comparison of gait variability in individuals with trans-tibial lower limb loss and trans femoral lower limb loss was the aim of the study. Methods: Ten individuals with traumatic unilateral trans femoral limb loss(TF), 12 individuals with traumatic transtibial lower limb loss(TT) and 12 healthy individuals(HI) were the participants of the study. All participants were evaluated with treadmill. Gait characteristics including mean step length, step length variability, ambulation index, time on each foot of participants were evaluated with treadmill. Participants were walked at their preferred speed for six minutes. Data from 4th minutes to 6th minutes were selected for statistical analyses to eliminate learning effect. Results: There were differences between the groups in intact limb step length variation, time on each foot, ambulation index and mean age (p < .05) according to the Kruskal Wallis Test. Pairwise analyses showed that there were differences between the TT and TF in residual limb variation (p=.041), time on intact foot (p=.024), time on prosthetic foot(p=.024), ambulation index(p = .003) in favor of TT group. There were differences between the TT and HI group in intact limb variation (p = .002), time on intact foot (p<.001), time on prosthetic foot (p < .001), ambulation index result (p < .001) in favor of HI group. There were differences between the TF and HI group in intact limb variation (p = .001), time on intact foot (p=.01) ambulation index result (p < .001) in favor of HI group. There was difference between the groups in mean age result from HI group were younger (p < .05).There were similarity between the groups in step lengths (p>.05) and time of prosthesis using in individuals with lower limb loss (p > .05). Conclusions: The pilot study provided basic data about gait stability in individuals with traumatic lower limb loss. Results of the study showed that to evaluate the gait differences between in different amputation level, long-range gait analyses methods may be useful to get more valuable information. On the other hand, similarity in step length may be resulted from effective prosthetic using or effective gait rehabilitation, in conclusion, all participants with lower limb loss were already trained. The differences between the TT and HI; TF and HI may be resulted from the age related features, therefore, age matched population in HI were recommended future studies. Increasing the number of participants and comparison of age-matched groups also recommended to generalize these result.

Keywords: lower limb loss, amputee, gait variability, gait analyses

Procedia PDF Downloads 254
7 High Capacity SnO₂/Graphene Composite Anode Materials for Li-Ion Batteries

Authors: Hilal Köse, Şeyma Dombaycıoğlu, Ali Osman Aydın, Hatem Akbulut

Abstract:

Rechargeable lithium-ion batteries (LIBs) have become promising power sources for a wide range of applications, such as mobile communication devices, portable electronic devices and electrical/hybrid vehicles due to their long cycle life, high voltage and high energy density. Graphite, as anode material, has been widely used owing to its extraordinary electronic transport properties, large surface area, and high electrocatalytic activities although its limited specific capacity (372 mAh g-1) cannot fulfil the increasing demand for lithium-ion batteries with higher energy density. To settle this problem, many studies have been taken into consideration to investigate new electrode materials and metal oxide/graphene composites are selected as a kind of promising material for lithium ion batteries as their specific capacities are much higher than graphene. Among them, SnO₂, an n-type and wide band gap semiconductor, has attracted much attention as an anode material for the new-generation lithium-ion batteries with its high theoretical capacity (790 mAh g-1). However, it suffers from large volume changes and agglomeration associated with the Li-ion insertion and extraction processes, which brings about failure and loss of electrical contact of the anode. In addition, there is also a huge irreversible capacity during the first cycle due to the formation of amorphous Li₂O matrix. To obtain high capacity anode materials, we studied on the synthesis and characterization of SnO₂-Graphene nanocomposites and investigated the capacity of this free-standing anode material in this work. For this aim, firstly, graphite oxide was obtained from graphite powder using the method described by Hummers method. To prepare the nanocomposites as free-standing anode, graphite oxide particles were ultrasonicated in distilled water with SnO2 nanoparticles (1:1, w/w). After vacuum filtration, the GO-SnO₂ paper was peeled off from the PVDF membrane to obtain a flexible, free-standing GO paper. Then, GO structure was reduced in hydrazine solution. Produced SnO2- graphene nanocomposites were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), and X-ray diffraction (XRD) analyses. CR2016 cells were assembled in a glove box (MBraun-Labstar). The cells were charged and discharged at 25°C between fixed voltage limits (2.5 V to 0.2 V) at a constant current density on a BST8-MA MTI model battery tester with 0.2C charge-discharge rate. Cyclic voltammetry (CV) was performed at the scan rate of 0.1 mVs-1 and electrochemical impedance spectroscopy (EIS) measurements were carried out using Gamry Instrument applying a sine wave of 10 mV amplitude over a frequency range of 1000 kHz-0.01 Hz.

Keywords: SnO₂-graphene, nanocomposite, anode, Li-ion battery

Procedia PDF Downloads 199
6 Comparison of the Chest X-Ray and Computerized Tomography Scans Requested from the Emergency Department

Authors: Sahabettin Mete, Abdullah C. Hocagil, Hilal Hocagil, Volkan Ulker, Hasan C. Taskin

Abstract:

Objectives and Goals: An emergency department is a place where people can come for a multitude of reasons 24 hours a day. As it is an easy, accessible place, thanks to self-sacrificing people who work in emergency departments. But the workload and overcrowding of emergency departments are increasing day by day. Under these circumstances, it is important to choose a quick, easily accessible and effective test for diagnosis. This results in laboratory and imaging tests being more than 40% of all emergency department costs. Despite all of the technological advances in imaging methods and available computerized tomography (CT), chest X-ray, the older imaging method, has not lost its appeal and effectiveness for nearly all emergency physicians. Progress in imaging methods are very convenient, but physicians should consider the radiation dose, cost, and effectiveness, as well as imaging methods to be carefully selected and used. The aim of the study was to investigate the effectiveness of chest X-ray in immediate diagnosis against the advancing technology by comparing chest X-ray and chest CT scan results of the patients in the emergency department. Methods: Patients who applied to Bulent Ecevit University Faculty of Medicine’s emergency department were investigated retrospectively in between 1 September 2014 and 28 February 2015. Data were obtained via MIAMED (Clear Canvas Image Server v6.2, Toronto, Canada), information management system which patients’ files are saved electronically in the clinic, and were retrospectively scanned. The study included 199 patients who were 18 or older, had both chest X-ray and chest CT imaging. Chest X-ray images were evaluated by the emergency medicine senior assistant in the emergency department, and the findings were saved to the study form. CT findings were obtained from already reported data by radiology department in the clinic. Chest X-ray was evaluated with seven questions in terms of technique and dose adequacy. Patients’ age, gender, application complaints, comorbid diseases, vital signs, physical examination findings, diagnosis, chest X-ray findings and chest CT findings were evaluated. Data saved and statistical analyses have made via using SPSS 19.0 for Windows. And the value of p < 0.05 were accepted statistically significant. Results: 199 patients were included in the study. In 38,2% (n=76) of all patients were diagnosed with pneumonia and it was the most common diagnosis. The chest X-ray imaging technique was appropriate in patients with the rate of 31% (n=62) of all patients. There was not any statistically significant difference (p > 0.05) between both imaging methods (chest X-ray and chest CT) in terms of determining the rates of displacement of the trachea, pneumothorax, parenchymal consolidation, increased cardiothoracic ratio, lymphadenopathy, diaphragmatic hernia, free air levels in the abdomen (in sections including the image), pleural thickening, parenchymal cyst, parenchymal mass, parenchymal cavity, parenchymal atelectasis and bone fractures. Conclusions: When imaging findings, showing cases that needed to be quickly diagnosed, were investigated, chest X-ray and chest CT findings were matched at a high rate in patients with an appropriate imaging technique. However, chest X-rays, evaluated in the emergency department, were frequently taken with an inappropriate technique.

Keywords: chest x-ray, chest computerized tomography, chest imaging, emergency department

Procedia PDF Downloads 155
5 Fibroblast Compatibility of Core-Shell Coaxially Electrospun Hybrid Poly(ε-Caprolactone)/Chitosan Scaffolds

Authors: Hilal Turkoglu Sasmazel, Ozan Ozkan, Seda Surucu

Abstract:

Tissue engineering is the field of treating defects caused by injuries, trauma or acute/chronic diseases by using artificial scaffolds that mimic the extracellular matrix (ECM), the natural biological support for the tissues and cells within the body. The main aspects of a successful artificial scaffold are (i) large surface area in order to provide multiple anchorage points for cells to attach, (ii) suitable porosity in order to achieve 3 dimensional growth of the cells within the scaffold as well as proper transport of nutrition, biosignals and waste and (iii) physical, chemical and biological compatibility of the material in order to obtain viability throughout the healing process. By hybrid scaffolds where two or more different materials were combined with advanced fabrication techniques into complex structures, it is possible to combine the advantages of individual materials into one single structure while eliminating the disadvantages of each. Adding this to the complex structure provided by advanced fabrication techniques enables obtaining the desired aspects of a successful artificial tissue scaffold. In this study, fibroblast compatibility of poly(ε-caprolactone) (PCL)/chitosan core-shell electrospun hybrid scaffolds with proper mechanical, chemical and physical properties successfully developed in our previous study was investigated. Standard 7-day cell culture was carried out with L929 fibroblast cell line. The viability of the cells cultured with the scaffolds was monitored with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay for every 48 h starting with 24 h after the initial seeding. In this assay, blank commercial tissue culture polystyrene (TCPS) Petri dishes, single electrospun PCL and single electrospun chitosan mats were used as control in order to compare and contrast the performance of the hybrid scaffolds. The adhesion, proliferation, spread and growth of the cells on/within the scaffolds were observed visually on the 3rd and the 7th days of the culture period with confocal laser scanning microscopy (CSLM) and scanning electron microscopy (SEM). The viability assay showed that the hybrid scaffolds caused no toxicity for fibroblast cells and provided a steady increase in cell viability, effectively doubling the cell density for every 48 h for the course of 7 days, as compared to TCPS, single electrospun PCL or chitosan mats. The cell viability on the hybrid scaffold was ~2 fold better compared to TCPS because of its 3D ECM-like structure compared to 2D flat surface of commercially cell compatible TCPS, and the performance was ~2 fold and ~10 fold better compared to single PCL and single chitosan mats, respectively, even though both fabricated similarly with electrospinning as non-woven fibrous structures, because single PCL and chitosan mats were either too hydrophobic or too hydrophilic to maintain cell attachment points. The viability results were verified with visual images obtained with CSLM and SEM, in which cells found to achieve characteristic spindle-like fibroblast shape and spread on the surface as well within the pores successfully at high densities.

Keywords: chitosan, core-shell, fibroblast, electrospinning, PCL

Procedia PDF Downloads 138
4 Development of PCL/Chitosan Core-Shell Electrospun Structures

Authors: Hilal T. Sasmazel, Seda Surucu

Abstract:

Skin tissue engineering is a promising field for the treatment of skin defects using scaffolds. This approach involves the use of living cells and biomaterials to restore, maintain, or regenerate tissues and organs in the body by providing; (i) larger surface area for cell attachment, (ii) proper porosity for cell colonization and cell to cell interaction, and (iii) 3-dimensionality at macroscopic scale. Recent studies on this area mainly focus on fabrication of scaffolds that can closely mimic the natural extracellular matrix (ECM) for creation of tissue specific niche-like environment at the subcellular scale. Scaffolds designed as ECM-like architectures incorporating into the host with minimal scarring/pain and facilitate angiogenesis. This study is related to combining of synthetic PCL and natural chitosan polymers to form 3D PCL/Chitosan core-shell structures for skin tissue engineering applications. Amongst the polymers used in tissue engineering, natural polymer chitosan and synthetic polymer poly(ε-caprolactone) (PCL) are widely preferred in the literature. Chitosan has been among researchers for a very long time because of its superior biocompatibility and structural resemblance to the glycosaminoglycan of bone tissue. However, the low mechanical flexibility and limited biodegradability properties reveals the necessity of using this polymer in a composite structure. On the other hand, PCL is a versatile polymer due to its low melting point (60°C), ease of processability, degradability with non-enzymatic processes (hydrolysis) and good mechanical properties. Nevertheless, there are also several disadvantages of PCL such as its hydrophobic structure, limited bio-interaction and susceptibility to bacterial biodegradation. Therefore, it became crucial to use both of these polymers together as a hybrid material in order to overcome the disadvantages of both polymers and combine advantages of those. The scaffolds here were fabricated by using electrospinning technique and the characterizations of the samples were done by contact angle (CA) measurements, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-Ray Photoelectron spectroscopy (XPS). Additionally, gas permeability test, mechanical test, thickness measurement and PBS absorption and shrinkage tests were performed for all type of scaffolds (PCL, chitosan and PCL/chitosan core-shell). By using ImageJ launcher software program (USA) from SEM photographs the average inter-fiber diameter values were calculated as 0.717±0.198 µm for PCL, 0.660±0.070 µm for chitosan and 0.412±0.339 µm for PCL/chitosan core-shell structures. Additionally, the average inter-fiber pore size values exhibited decrease of 66.91% and 61.90% for the PCL and chitosan structures respectively, compare to PCL/chitosan core-shell structures. TEM images proved that homogenous and continuous bead free core-shell fibers were obtained. XPS analysis of the PCL/chitosan core-shell structures exhibited the characteristic peaks of PCL and chitosan polymers. Measured average gas permeability value of produced PCL/chitosan core-shell structure was determined 2315±3.4 g.m-2.day-1. In the future, cell-material interactions of those developed PCL/chitosan core-shell structures will be carried out with L929 ATCC CCL-1 mouse fibroblast cell line. Standard MTT assay and microscopic imaging methods will be used for the investigation of the cell attachment, proliferation and growth capacities of the developed materials.

Keywords: chitosan, coaxial electrospinning, core-shell, PCL, tissue scaffold

Procedia PDF Downloads 458
3 Fabrication of Zeolite Modified Cu Doped ZnO Films and Their Response towards Nitrogen Monoxide

Authors: Irmak Karaduman, Tugba Corlu, Sezin Galioglu, Burcu Akata, M. Ali Yildirim, Aytunç Ateş, Selim Acar

Abstract:

Breath analysis represents a promising non-invasive, fast and cost-effective alternative to well-established diagnostic and monitoring techniques such as blood analysis, endoscopy, ultrasonic and tomographic monitoring. Portable, non-invasive, and low-cost breath analysis devices are becoming increasingly desirable for monitoring different diseases, especially asthma. Beacuse of this, NO gas sensing at low concentrations has attracted progressive attention for clinical analysis in asthma. Recently, nanomaterials based sensors are considered to be a promising clinical and laboratory diagnostic tool, because its large surface–to–volume ratio, controllable structure, easily tailored chemical and physical properties, which bring high sensitivity, fast dynamic processand even the increasing specificity. Among various nanomaterials, semiconducting metal oxides are extensively studied gas-sensing materials and are potential sensing elements for breathanalyzer due to their high sensitivity, simple design, low cost and good stability.The sensitivities of metal oxide semiconductor gas sensors can be enhanced by adding noble metals. Doping contents, distribution, and size of metallic or metal oxide catalysts are key parameters for enhancing gas selectivity as well as sensitivity. By manufacturing doping MOS structures, it is possible to develop more efficient sensor sensing layers. Zeolites are perhaps the most widely employed group of silicon-based nanoporous solids. Their well-defined pores of sub nanometric size have earned them the name of molecular sieves, meaning that operation in the size exclusion regime is possible by selecting, among over 170 structures available, the zeolite whose pores allow the pass of the desired molecule, while keeping larger molecules outside.In fact it is selective adsorption, rather than molecular sieving, the mechanism that explains most of the successful gas separations achieved with zeolite membranes. In view of their molecular sieving and selective adsorption properties, it is not surprising that zeolites have found use in a number of works dealing with gas sensing devices. In this study, the Cu doped ZnO nanostructure film was produced by SILAR method and investigated the NO gas sensing properties. To obtain the selectivity of the sample, the gases including CO,NH3,H2 and CH4 were detected to compare with NO. The maximum response is obtained at 85 C for 20 ppb NO gas. The sensor shows high response to NO gas. However, acceptable responses are calculated for CO and NH3 gases. Therefore, there are no responses obtain for H2 and CH4 gases. Enhanced to selectivity, Cu doped ZnO nanostructure film was coated with zeolite A thin film. It is found that the sample possess an acceptable response towards NO hardly respond to CO, NH3, H2 and CH4 at room temperature. This difference in the response can be expressed in terms of differences in the molecular structure, the dipole moment, strength of the electrostatic interaction and the dielectric constant. The as-synthesized thin film is considered to be one of the extremely promising candidate materials in electronic nose applications. This work is supported by The Scientific and Technological Research Council of Turkey (TUBİTAK) under Project No, 115M658 and Gazi University Scientific Research Fund under project no 05/2016-21.

Keywords: Cu doped ZnO, electrical characterization, gas sensing, zeolite

Procedia PDF Downloads 258
2 Investigation of Different Electrolyte Salts Effect on ZnO/MWCNT Anode Capacity in LIBs

Authors: Şeyma Dombaycıoğlu, Hilal Köse, Ali Osman Aydın, Hatem Akbulut

Abstract:

Rechargeable lithium ion batteries (LIBs) have been considered as one of the most attractive energy storage choices for laptop computers, electric vehicles and cellular phones owing to their high energy and power density. Compared with conventional carbonaceous materials, transition metal oxides (TMOs) have attracted great interests and stand out among versatile novel anode materials due to their high theoretical specific capacity, wide availability and good safety performance. ZnO, as an anode material for LIBs, has a high theoretical capacity of 978 mAh g-1, much higher than that of the conventional graphite anode (∼370 mAhg-1). However, several major problems such as poor cycleability, resulting from the severe volume expansion and contraction during the alloying-dealloying cycles with Li+ ions and the associated charge transfer process, the pulverization and the agglomeration of individual particles, which drastically reduces the total entrance/exit sites available for Li+ ions still hinder the practical use of ZnO powders as an anode material for LIBs. Therefore, a great deal of effort has been devoted to overcome these problems, and many methods have been developed. In most of these methods, it is claimed that carbon nanotubes (CNTs) will radically improve the performance of batteries, because their unique structure may especially enhance the kinetic properties of the electrodes and result in an extremely high specific charge compared with the theoretical limits of graphitic carbon. Due to outstanding properties of CNTs, MWCNT buckypaper substrate is considered a buffer material to prevent mechanical disintegration of anode material during the battery applications. As the bridge connecting the positive and negative electrodes, the electrolyte plays a critical role affecting the overall electrochemical performance of the cell including rate, capacity, durability and safety. Commercial electrolytes for Li-ion batteries normally consist of certain lithium salts and mixed organic linear and cyclic carbonate solvents. Most commonly, LiPF6 is attributed to its remarkable features including high solubility, good ionic conductivity, high dissociation constant and satisfactory electrochemical stability for commercial fabrication. Besides LiPF6, LiBF4 is well known as a conducting salt for LIBs. LiBF4 shows a better temperature stability in organic carbonate based solutions and less moisture sensitivity compared to LiPF6. In this work, free standing zinc oxide (ZnO) and multiwalled carbon nanotube (MWCNT) nanocomposite materials were prepared by a sol gel technique giving a high capacity anode material for lithium ion batteries. Electrolyte solutions (including 1 m Li+ ion) were prepared with different Li salts in glove box. For this purpose, LiPF6 and LiBF4 salts and also mixed of these salts were solved in EC:DMC solvents (1:1, w/w). CR2016 cells were assembled by using these prepared electrolyte solutions, the ZnO/MWCNT buckypaper nanocomposites as working electrodes, metallic lithium as cathode and polypropylene (PP) as separator. For investigating the effect of different Li salts on the electrochemical performance of ZnO/MWCNT nanocomposite anode material electrochemical tests were performed at room temperature.

Keywords: anode, electrolyte, Li-ion battery, ZnO/MWCNT

Procedia PDF Downloads 208
1 Flood Risk Management in the Semi-Arid Regions of Lebanon - Case Study “Semi Arid Catchments, Ras Baalbeck and Fekha”

Authors: Essam Gooda, Chadi Abdallah, Hamdi Seif, Safaa Baydoun, Rouya Hdeib, Hilal Obeid

Abstract:

Floods are common natural disaster occurring in semi-arid regions in Lebanon. This results in damage to human life and deterioration of environment. Despite their destructive nature and their immense impact on the socio-economy of the region, flash floods have not received adequate attention from policy and decision makers. This is mainly because of poor understanding of the processes involved and measures needed to manage the problem. The current understanding of flash floods remains at the level of general concepts; most policy makers have yet to recognize that flash floods are distinctly different from normal riverine floods in term of causes, propagation, intensity, impacts, predictability, and management. Flash floods are generally not investigated as a separate class of event but are rather reported as part of the overall seasonal flood situation. As a result, Lebanon generally lacks policies, strategies, and plans relating specifically to flash floods. Main objective of this research is to improve flash flood prediction by providing new knowledge and better understanding of the hydrological processes governing flash floods in the East Catchments of El Assi River. This includes developing rainstorm time distribution curves that are unique for this type of study region; analyzing, investigating, and developing a relationship between arid watershed characteristics (including urbanization) and nearby villages flow flood frequency in Ras Baalbeck and Fekha. This paper discusses different levels of integration approach¬es between GIS and hydrological models (HEC-HMS & HEC-RAS) and presents a case study, in which all the tasks of creating model input, editing data, running the model, and displaying output results. The study area corresponds to the East Basin (Ras Baalbeck & Fakeha), comprising nearly 350 km2 and situated in the Bekaa Valley of Lebanon. The case study presented in this paper has a database which is derived from Lebanese Army topographic maps for this region. Using ArcMap to digitizing the contour lines, streams & other features from the topographic maps. The digital elevation model grid (DEM) is derived for the study area. The next steps in this research are to incorporate rainfall time series data from Arseal, Fekha and Deir El Ahmar stations to build a hydrologic data model within a GIS environment and to combine ArcGIS/ArcMap, HEC-HMS & HEC-RAS models, in order to produce a spatial-temporal model for floodplain analysis at a regional scale. In this study, HEC-HMS and SCS methods were chosen to build the hydrologic model of the watershed. The model then calibrated using flood event that occurred between 7th & 9th of May 2014 which considered exceptionally extreme because of the length of time the flows lasted (15 hours) and the fact that it covered both the watershed of Aarsal and Ras Baalbeck. The strongest reported flood in recent times lasted for only 7 hours covering only one watershed. The calibrated hydrologic model is then used to build the hydraulic model & assessing of flood hazards maps for the region. HEC-RAS Model is used in this issue & field trips were done for the catchments in order to calibrated both Hydrologic and Hydraulic models. The presented models are a kind of flexible procedures for an ungaged watershed. For some storm events it delivers good results, while for others, no parameter vectors can be found. In order to have a general methodology based on these ideas, further calibration and compromising of results on the dependence of many flood events parameters and catchment properties is required.

Keywords: flood risk management, flash flood, semi arid region, El Assi River, hazard maps

Procedia PDF Downloads 457