Search results for: transient contact
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2303

Search results for: transient contact

1703 Ethnolinguistic Otherness: The Vedda Language (Baasapojja) of Indigenous Adivasi (Veddas) of Dambana in Sri Lanka

Authors: Nimasha Malalasekera

Abstract:

Working with the indigenous Adivasi (Vedda) community of Dambana in the district of Badulla in Sri Lanka, this research documents linguistic data to address language and cultural endangerment. The ancestral language of Adivasi has undergone sustained restructuration over a long historical period due to its contact with Sinhala, an Indo-Aryan language spoken by the majority Sinhalese. The Vedda language is highly endangered today. At present, all speakers of the Vedda language spoken in Dambana are Adivasi men in the parent generation, who are Sinhala-Vedda bilinguals. Adivasi women and children do not speak the Vedda language but Sinhala in everyday life. Women can understand the Vedda language and would respond to a Vedda language utterance in Sinhala. The use of the Vedda language is largely restricted to self-ascribing Adivasi men who employ it in the context of cultural tourism in Dambana to index ethnolinguistic otherness. Adivasi of Dambana often refers to this distinct linguistic code that they speak as baasapojja or language. This research employs a cooperative model of ethnographic documentation to explore the interrelations between discursive practices, linguistic structures, and linguistic (and broader sociocultural) ideologies in this community. The Vedda language has been previously identified as a dialect of Sinhala or a creole emerging in the contact between Sinhala and the ancestral Vedda language. This paper analyzes the current language endangerment context of bilingual Adivasi members that allows the birth of a mixed language. The aim of this research is to preserve ongoing linguistic innovation among this endangered language speech community. It contributes to the appreciation of creative cultural and linguistic production of a stigmatized minuscule indigenous community of South Asia that strives to assert a distinct linguistic and cultural identity from the dominant populations.

Keywords: Vedda language, language endangerment, mixed languages, indigenous identity

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1702 Failure Pressure Prediction of a Corroded Pipeline Using a Finite Element Method

Authors: Lounes Aouane, Omar Bouledroua

Abstract:

Sonatrach uses 24,000 kilometers of pipelines to transport gas and oil. Over time, these pipes run the risk of bursting due to corrosion inside and/or outside the pipeline. For this reason, a check must be made with the help of an equipped scraper. This intelligent tool provides a detailed picture of all errors in the pipeline. Based on the ERF values, these wear defects are divided into two parts: acceptable defect and unacceptable defect. The objective of this work is to conduct a comparative study of the different methods of calculating the marginal pressure found in the literature (DNV RP F-101, SHELL, P-CORRC, NETTO and CSA Z662). This comparison will be made from a database of 329 burst tests published in the literature. Finally, we will propose a new approach based on the finite element method using the commercial software ANSYS.

Keywords: hydrogen embrittlement, pipelines, hydrogen, transient flow, cyclic pressure, fatigue crack growth

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1701 Numerical Analysis of Water Hammer in a Viscoelastic Pipe System Considering Fluid Structure Interaction

Authors: N. Tavakoli Shirazi

Abstract:

This study investigates the effects of pipe-wall viscoelasticity on water hammer pressures. Tests have been conducted in a reservoir-pipe-valve system configured of a main viscoelastic pipeline and two short steel pipes placed upstream and downstream of the main pipe. Rapid closure of a manually operated valve at the downstream end generates water hammer. Experimental measurements at several positions along the pipeline have been collected from the papers. Computer simulations of the experiment have been performed and the results of runs with various options affecting the water hammer are provided and discussed. It is shown that the incorporation of viscoelastic pipe wall mechanical behavior in the hydraulic transient model contributes to a favorable fitting between numerical results and observed data.

Keywords: pipe system, PVC pipe, viscoelasticity, water hammer

Procedia PDF Downloads 444
1700 A New Center of Motion in Cabling Robots

Authors: Alireza Abbasi Moshaii, Farshid Najafi

Abstract:

In this paper a new model for centre of motion creating is proposed. This new method uses cables. So, it is very useful in robots because it is light and has easy assembling process. In the robots which need to be in touch with some things this method is very good. It will be described in the following. The accuracy of the idea is proved by an experiment. This system could be used in the robots which need a fixed point in the contact with some things and make a circular motion. Such as dancer, physician or repair robots.

Keywords: centre of motion, robotic cables, permanent touching, mechatronics engineering

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1699 Starting Characteristic Analysis of LSPM for Pumping System Considering Demagnetization

Authors: Subrato Saha, Yun-Hyun Cho

Abstract:

This paper presents the design process of a high performance 3-phase 3.7 kW 2-pole line start permanent magnet synchronous motor for pumping system. A method was proposed to study the starting torque characteristics considering line start with high inertia load. A d-q model including cage was built to study the synchronization capability. Time-stepping finite element method analysis was utilized to accurately predict the dynamic and transient performance, efficiency, starting current, speed curve and, etc. Considering the load torque of pumps during starting stage, the rotor bar was designed with minimum demagnetization of permanent magnet caused by huge starting current.

Keywords: LSPM, starting analysis, demagnetization, FEA, pumping system

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1698 The Psychology of Cross-Cultural Communication: A Socio-Linguistics Perspective

Authors: Tangyie Evani, Edmond Biloa, Emmanuel Nforbi, Lem Lilian Atanga, Kom Beatrice

Abstract:

The dynamics of languages in contact necessitates a close study of how its users negotiate meanings from shared values in the process of cross-cultural communication. A transverse analysis of the situation demonstrates the existence of complex efforts on connecting cultural knowledge to cross-linguistic competencies within a widening range of communicative exchanges. This paper sets to examine the psychology of cross-cultural communication in a multi-linguistic setting like Cameroon where many local and international languages are in close contact. The paper equally analyses the pertinence of existing macro sociological concepts as fundamental knowledge traits in literal and idiomatic cross semantic mapping. From this point, the article presents a path model of connecting sociolinguistics to the increasing adoption of a widening range of communicative genre piloted by the on-going globalisation trends with its high-speed information technology machinery. By applying a cross cultural analysis frame, the paper will be contributing to a better understanding of the fundamental changes in the nature and goals of cross-cultural knowledge in pragmatics of communication and cultural acceptability’s. It emphasises on the point that, in an era of increasing global interchange, a comprehensive inclusive global culture through bridging gaps in cross-cultural communication would have significant potentials to contribute to achieving global social development goals, if inadequacies in language constructs are adjusted to create avenues that intertwine with sociocultural beliefs, ensuring that meaningful and context bound sociolinguistic values are observed within the global arena of communication.

Keywords: cross-cultural communication, customary language, literalisms, primary meaning, subclasses, transubstantiation

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1697 YPFS Attenuating TH2 Cell-Mediated Allergic Inflammation by Regulating the TSLP Pathway

Authors: Xi Yu, Lili Gu, Huizhu Wang, Xiao Wei, Dandan Sheng, Xiaoyan Jiang, Min Hong

Abstract:

Introduction: Hypersensitivity disease is difficult to cure completely because of its recurrence, yupingfengsan (YPFS) is used to treat the diseases with the advantage of reducing the recurrence,but the precise mechanism is not clear. Previous studies of our laboratory have shown that the extract of YPFS can inhibit Th2-type allergic contact dermatitis(ACD) induced by FITC.Besides, thymic stromal lymphopoietin(TSLP) have been proved to be a master switch for allergic inflammation. Based on these studies, we want to establish a mouse model of TSLP production based on Th2 cell-mediated allergic inflammation to explore the regulating mechanisms of YPFS on TSLP in Th2 cell-mediated allergic inflammation. Methods: Th2-type ACD mouse model: The mice were topically sensitized on the abdomens (induction phase) and elicited on its ears skin 6 day later (excitation phase) with FITC solution, and the ear swelling was measured to evaluate the allergic inflammation;A mouse model of TSLP production based on Th2 cell-mediated allergic inflammation (TSLP production model): the skin of the ear was sensitized on two consecutive days with FITC solution causing the production of TSLP;Mice were treated with YPFS extract,ELISA、Real-time PCR and Western-blotting were using to examine the mRNA and protein levels of TSLP\TSLPR and TLRs ect. Results: YPFS extract can attenuates Th2-type allergic inflammatory in mice;in TSLP production model, YPFS can inhibit the expression of TSLP、 TSLPR、TLRs and MyD88, So we deduce the possible mechanisms of YPFS to play a role of intervention is through TLRs- MyD88 dependent and independent pathway to reduce TSLP production.

Keywords: YPFS, TSLP, TLRs, Th2-type allergic contact dermatitis

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1696 Multi-Particle Finite Element Modelling Simulation Based on Cohesive Zone Method of Cold Compaction Behavior of Laminar Al and NaCl Composite Powders

Authors: Yanbing Feng, Deqing Mei, Yancheng Wang, Zichen Chen

Abstract:

With the advantage of low volume density, high specific surface area, light weight and good permeability, porous aluminum material has the potential to be used in automotive, railway, chemistry and construction industries, etc. A layered powder sintering and dissolution method were developed to fabricate the porous surface Al structure with high efficiency. However, the densification mechanism during the cold compaction of laminar composite powders is still unclear. In this study, multi particle finite element modelling (MPFEM) based on the cohesive zone method (CZM) is used to simulate the cold compaction behavior of laminar Al and NaCl composite powders. To obtain its densification mechanism, the macro and micro properties of final compacts are characterized and analyzed. The robustness and accuracy of the numerical model is firstly verified by experimental results and data fitting. The results indicate that the CZM-based multi particle FEM is an effective way to simulate the compaction of the laminar powders and the fracture process of the NaCl powders. In the compaction of the laminar powders, the void is mainly filled by the particle rearrangement, plastic deformation of Al powders and brittle fracture of NaCl powders. Large stress is mainly concentrated within the NaCl powers and the contact force network is formed. The Al powder near the NaCl powder or the mold has larger stress distribution on its contact surface. Therefore, the densification process of cold compaction of laminar Al and NaCl composite powders is successfully analyzed by the CZM-based multi particle FEM.

Keywords: cold compaction, cohesive zone, multi-particle FEM, numerical modeling, powder forming

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1695 Automated Computer-Vision Analysis Pipeline of Calcium Imaging Neuronal Network Activity Data

Authors: David Oluigbo, Erik Hemberg, Nathan Shwatal, Wenqi Ding, Yin Yuan, Susanna Mierau

Abstract:

Introduction: Calcium imaging is an established technique in neuroscience research for detecting activity in neural networks. Bursts of action potentials in neurons lead to transient increases in intracellular calcium visualized with fluorescent indicators. Manual identification of cell bodies and their contours by experts typically takes 10-20 minutes per calcium imaging recording. Our aim, therefore, was to design an automated pipeline to facilitate and optimize calcium imaging data analysis. Our pipeline aims to accelerate cell body and contour identification and production of graphical representations reflecting changes in neuronal calcium-based fluorescence. Methods: We created a Python-based pipeline that uses OpenCV (a computer vision Python package) to accurately (1) detect neuron contours, (2) extract the mean fluorescence within the contour, and (3) identify transient changes in the fluorescence due to neuronal activity. The pipeline consisted of 3 Python scripts that could both be easily accessed through a Python Jupyter notebook. In total, we tested this pipeline on ten separate calcium imaging datasets from murine dissociate cortical cultures. We next compared our automated pipeline outputs with the outputs of manually labeled data for neuronal cell location and corresponding fluorescent times series generated by an expert neuroscientist. Results: Our results show that our automated pipeline efficiently pinpoints neuronal cell body location and neuronal contours and provides a graphical representation of neural network metrics accurately reflecting changes in neuronal calcium-based fluorescence. The pipeline detected the shape, area, and location of most neuronal cell body contours by using binary thresholding and grayscale image conversion to allow computer vision to better distinguish between cells and non-cells. Its results were also comparable to manually analyzed results but with significantly reduced result acquisition times of 2-5 minutes per recording versus 10-20 minutes per recording. Based on these findings, our next step is to precisely measure the specificity and sensitivity of the automated pipeline’s cell body and contour detection to extract more robust neural network metrics and dynamics. Conclusion: Our Python-based pipeline performed automated computer vision-based analysis of calcium image recordings from neuronal cell bodies in neuronal cell cultures. Our new goal is to improve cell body and contour detection to produce more robust, accurate neural network metrics and dynamic graphs.

Keywords: calcium imaging, computer vision, neural activity, neural networks

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1694 Impaired Transient Receptor Potential Vanilloid 4-Mediated Dilation of Mesenteric Arteries in Spontaneously Hypertensive Rats

Authors: Ammar Boudaka, Maryam Al-Suleimani, Hajar BaOmar, Intisar Al-Lawati, Fahad Zadjali

Abstract:

Background: Hypertension is increasingly becoming a matter of medical and public health importance. The maintenance of normal blood pressure requires a balance between cardiac output and total peripheral resistance. The endothelium, through the release of vasodilating factors, plays an important role in the control of total peripheral resistance and hence blood pressure homeostasis. Transient Receptor Potential Vanilloid type 4 (TRPV4) is a mechanosensitive non-selective cation channel that is expressed on the endothelium and contributes to endothelium-mediated vasodilation. So far, no data are available about the morphological and functional status of this channel in hypertensive cases. Objectives: This study aimed to investigate whether there is any difference in the morphological and functional features of TRPV4 in the mesenteric artery of normotensive and hypertensive rats. Methods: Functional feature of TRPV4 in four experimental animal groups: young and adult Wistar-Kyoto rats (WKY-Y and WKY-A), young and adult spontaneously hypertensive rats (SHR-Y and SHR-A), was studied by adding 5 µM 4αPDD (TRPV4 agonist) to mesenteric arteries mounted in a four-chamber wire myograph and pre-contracted with 4 µM phenylephrine. The 4αPDD-induced response was investigated in the presence and absence of 1 µM HC067047 (TRPV4 antagonist), 100 µM L-NAME (nitric oxide synthase inhibitor), and endothelium. The morphological distribution of TRPV4 in the wall of rat mesenteric arteries was investigated by immunostaining. Real-time PCR was used in order to investigate mRNA expression level of TRPV4 in the mesenteric arteries of the four groups. The collected data were expressed as mean ± S.E.M. with n equal to the number of animals used (one vessel was taken from each rat). To determine the level of significance, statistical comparisons were performed using the student’s t-test and considered to be significantly different at p<0.05. Results: 4αPDD induced a relaxation response in the mesenteric arterial preparations (WKY-Y: 85.98% ± 4.18; n = 5) that was markedly inhibited by HC067047 (18.30% ± 2.86; n= 5; p<0.05), endothelium removal (19.93% ± 1.50; n = 5; p<0.05) and L-NAME (28.18% ± 3.09; n = 5; p<0.05). The 4αPDD-induced relaxation was significantly lower in SHR-Y compared to WKY-Y (SHR-Y: 70.96% ± 3.65; n = 6, WKY-Y: 85.98% ± 4.18; n = 5-6, p<0.05. Moreover, the 4αPDD-induced response was significantly lower in WKY-A than WKY-Y (WKY-A: 75.58 ± 1.30; n = 5, WKY-Y: 85.98% ± 4.18; n = 5, p<0.05). Immunostaining study showed immunofluorescent signal confined to the endothelial layer of the mesenteric arteries. The expression of TRPV4 mRNA in SHR-Y was significantly lower than in WKY-Y (SHR-Y; 0.67RU ± 0.34; n = 4, WKY-Y: 2.34RU ± 0.15; n = 4, p<0.05). Furthermore, TRPV4 mRNA expression in WKY-A was lower than its expression in WKY-Y (WKY-A: 0.62RU ± 0.37; n = 4, WKY-Y: 2.34RU ± 0.15; n = 4, p<0.05). Conclusion: Stimulation of TRPV4, which is expressed on the endothelium of rat mesenteric artery, triggers an endothelium-mediated relaxation response that markedly decreases with hypertension and growing up changes due to downregulation of TRPV4 expression.

Keywords: hypertension, endothelium, mesenteric artery, TRPV4

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1693 2017 Survey on Correlation between Connection and Emotions for Children and Adolescents

Authors: Ya-Hsing Yeh, I-Chun Tai, Ming-Chieh Lin, Li-Ting Lee, Ping-Ting Hsieh, Yi-Chen Ling, Jhia-Ying Du, Li-Ping Chang, Guan-Long Yu

Abstract:

Objective: To understand the connection between children/adolescents and those who they miss, as well as the correlation between connection and their emotions. Method: Based on the objective, a close-ended questionnaire was made into a formal questionnaire after experts evaluated its validity. In February 2017, the paper-based questionnaire was adopted. Twenty-one elementary schools and junior high schools in Taiwan were sampled by purposive sampling approach and the fifth to ninth graders were our participants. A total of 2,502 valid questionnaires were retrieved. Results: Forty-four-point three percent of children/adolescents missed a person in mind, or they thought a person as a significant other in mind, but they had no connection with them. The highest proportion of those they wanted to contact with was ‘Friends and classmates’, and the others were ‘immediate family’, such as parents and grandparents, and ‘academic or vocational instructors, such as home-room teachers, coaches, cram school teachers and so on, respectively. Only 14% of children/adolescents would actively contact those they missed. The proportion of what children/adolescents ‘often’ actively keeping in touch with those they missed felt happy or cheerful was higher compared with those who ‘seldom’ actively keeping in touch with people they missed whenever they recalled who they missed, or the person actively contacted with them. Sixty-one-point seven percent of participants haven’t connected with those they missed for more than one year. The main reason was ‘environmental factors’, such as school/class transfer or moving, and then ‘academic or personal factors’, ‘communication tools’, and ‘personalities’, respectively. In addition to ‘greetings during festivals and holidays’, ‘hearing from those they missed’, and ‘knowing the latest information about those they missed on their Internet communities’, children/adolescents would like to actively contact with them when they felt ‘happy’ and ‘depressed or frustrated. The first three opinions of what children/adolescents regarded truly connection were ‘listening to people they missed attentively’, ‘sharing their secrets’, and ‘contacting with people they regularly missed with real actions’. In terms of gender, girls’ proportion on ‘showing with actions, including contacting with people they missed regularly or expressing their feelings openly’, and ‘sharing secrets’ was higher than boys’, while boy’s proportion on ‘the attitudes when contacting people they missed, including listening attentively or without being distracted’ was higher than girls’. Conclusions: I. The more ‘active’ connection they have, the more happiness they feel. II. Teachers can teach children how to manage their emotions and express their feelings appropriately. III. It is very important to turn connection into ‘action.’ Teachers can set a good example and share their moods with others whatever they are in the mood. This is a kind of connection.

Keywords: children, connection, emotion, mental health

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1692 A Simple Heat and Mass Transfer Model for Salt Gradient Solar Ponds

Authors: Safwan Kanan, Jonathan Dewsbury, Gregory Lane-Serff

Abstract:

A salinity gradient solar pond is a free energy source system for collecting, converting and storing solar energy as heat. In this paper, the principles of solar pond are explained. A mathematical model is developed to describe and simulate heat and mass transfer behavior of salinity gradient solar pond. Matlab codes are programmed to solve the one dimensional finite difference method for heat and mass transfer equations. Temperature profiles and concentration distributions are calculated. The numerical results are validated with experimental data and the results are found to be in good agreement.

Keywords: finite difference method, salt-gradient solar-pond, solar energy, transient heat and mass transfer

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1691 Geochemical Modeling of Mineralogical Changes in Rock and Concrete in Interaction with Groundwater

Authors: Barbora Svechova, Monika Licbinska

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Geochemical modeling of mineralogical changes of various materials in contact with an aqueous solution is an important tool for predicting the processes and development of given materials at the site. The modeling focused on the mutual interaction of groundwater at the contact with the rock mass and its subsequent influence on concrete structures. The studied locality is located in Slovakia in the area of the Liptov Basin, which is a significant inter-mountain lowland, which is bordered on the north and south by the core mountains belt of the Tatras, where in the center the crystalline rises to the surface accompanied by Mesozoic cover. Groundwater in the area is bound to structures with complicated geological structures. From the hydrogeological point of view, it is an environment with a crack-fracture character. The area is characterized by a shallow surface circulation of groundwater without a significant collector structure, and from a chemical point of view, groundwater in the area has been classified as calcium bicarbonate with a high content of CO2 and SO4 ions. According to the European standard EN 206-1, these are waters with medium aggression towards the concrete. Three rock samples were taken from the area. Based on petrographic and mineralogical research, they were evaluated as calcareous shale, micritic limestone and crystalline shale. These three rock samples were placed in demineralized water for one month and the change in the chemical composition of the water was monitored. During the solution-rock interaction there was an increase in the concentrations of all major ions, except nitrates. There was an increase in concentration after a week, but at the end of the experiment, the concentration was lower than the initial value. Another experiment was the interaction of groundwater from the studied locality with a concrete structure. The concrete sample was also left in the water for 1 month. The results of the experiment confirmed the assumption of a reduction in the concentrations of calcium and bicarbonate ions in water due to the precipitation of amorphous forms of CaCO3 on the surface of the sample.Vice versa, it was surprising to increase the concentration of sulphates, sodium, iron and aluminum due to the leaching of concrete. Chemical analyzes from these experiments were performed in the PHREEQc program, which calculated the probability of the formation of amorphous forms of minerals. From the results of chemical analyses and hydrochemical modeling of water collected in situ and water from experiments, it was found: groundwater at the site is unsaturated and shows moderate aggression towards reinforced concrete structures according to EN 206-1a, which will affect the homogeneity and integrity of concrete structures; from the rocks in the given area, Ca, Na, Fe, HCO3 and SO4. Unsaturated waters will dissolve everything as soon as they come into contact with the solid matrix. The speed of this process then depends on the physicochemical parameters of the environment (T, ORP, p, n, water retention time in the environment, etc.).

Keywords: geochemical modeling, concrete , dissolution , PHREEQc

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1690 Parameter Estimation of Induction Motors by PSO Algorithm

Authors: A. Mohammadi, S. Asghari, M. Aien, M. Rashidinejad

Abstract:

After emergent of alternative current networks and their popularity, asynchronous motors became more widespread than other kinds of industrial motors. In order to control and run these motors efficiently, an accurate estimation of motor parameters is needed. There are different methods to obtain these parameters such as rotor locked test, no load test, DC test, analytical methods, and so on. The most common drawback of these methods is their inaccuracy in estimation of some motor parameters. In order to remove this concern, a novel method for parameter estimation of induction motors using particle swarm optimization (PSO) algorithm is proposed. In the proposed method, transient state of motor is used for parameter estimation. Comparison of the simulation results purtuined to the PSO algorithm with other available methods justifies the effectiveness of the proposed method.

Keywords: induction motor, motor parameter estimation, PSO algorithm, analytical method

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1689 2D Monte Carlo Simulation of Grain Growth under Transient Conditions

Authors: K. R. Phaneesh, Anirudh Bhat, G. Mukherjee, K. T. Kashyap

Abstract:

Extensive Monte Carlo Potts model simulations were performed on 2D square lattice to investigate the effects of simulated higher temperatures effects on grain growth kinetics. A range of simulation temperatures (KTs) were applied on a matrix of size 10002 with Q-state 64, dispersed with a wide range of second phase particles, ranging from 0.001 to 0.1, and then run to 100,000 Monte Carlo steps. The average grain size, the largest grain size and the grain growth exponent were evaluated for all particle fractions and simulated temperatures. After evaluating several growth parameters, the critical temperature for a square lattice, with eight nearest neighbors, was found to be KTs = 0.4.

Keywords: average grain size, critical temperature, grain growth exponent, Monte Carlo steps

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1688 Stabilization of y-Sterilized Food, Packaging Materials by Synergistic Mixtures of Food-Contact Approval Stabilizers

Authors: Sameh A. S. Thabit Alariqi

Abstract:

Food is widely packaged with plastic materials to prevent microbial contamination and spoilage. Ionizing radiation is widely used to sterilize the food-packaging materials. Sterilization by γ-radiation causes degradation for the plastic packaging materials such as embrittlement, stiffening, softening, discoloration, odour generation, and decrease in molecular weight. Many antioxidants can prevent γ-degradation but most of them are toxic. The migration of antioxidants to its environment gives rise to major concerns in case of food packaging plastics. In this attempt, we have aimed to utilize synergistic mixtures of stabilizers which are approved for food-contact applications. Ethylene-propylene-diene terpolymer (EPDM) have been melt-mixed with hindered amine stabilizers (HAS), phenolic antioxidants and organo-phosphites (hydroperoxide decomposer). Results were discussed by comparing the stabilizing efficiency of mixtures with and without phenol system. Among phenol containing systems where we mostly observed discoloration due to the oxidation of hindered phenol, the combination of secondary HAS, tertiary HAS, organo-phosphite and hindered phenol exhibited improved stabilization efficiency than single or binary additive systems. The mixture of secondary HAS and tertiary HAS, has shown antagonistic effect of stabilization. However, the combination of organo-phosphite with secondary HAS, tertiary HAS and phenol antioxidants have been found to give synergistic even at higher doses of -sterilization. The effects have been explained through the interaction between the stabilizers. After γ-irradiation, the consumption of oligomeric stabilizer significantly depends on the components of stabilization mixture. The effect of the organo-phosphite antioxidant on the overall stability has been discussed.

Keywords: ethylene-propylene-diene terpolymer, synergistic mixtures, gamma sterilization, gamma stabilization

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1687 Temperature Contour Detection of Salt Ice Using Color Thermal Image Segmentation Method

Authors: Azam Fazelpour, Saeed Reza Dehghani, Vlastimil Masek, Yuri S. Muzychka

Abstract:

The study uses a novel image analysis based on thermal imaging to detect temperature contours created on salt ice surface during transient phenomena. Thermal cameras detect objects by using their emissivities and IR radiance. The ice surface temperature is not uniform during transient processes. The temperature starts to increase from the boundary of ice towards the center of that. Thermal cameras are able to report temperature changes on the ice surface at every individual moment. Various contours, which show different temperature areas, appear on the ice surface picture captured by a thermal camera. Identifying the exact boundary of these contours is valuable to facilitate ice surface temperature analysis. Image processing techniques are used to extract each contour area precisely. In this study, several pictures are recorded while the temperature is increasing throughout the ice surface. Some pictures are selected to be processed by a specific time interval. An image segmentation method is applied to images to determine the contour areas. Color thermal images are used to exploit the main information. Red, green and blue elements of color images are investigated to find the best contour boundaries. The algorithms of image enhancement and noise removal are applied to images to obtain a high contrast and clear image. A novel edge detection algorithm based on differences in the color of the pixels is established to determine contour boundaries. In this method, the edges of the contours are obtained according to properties of red, blue and green image elements. The color image elements are assessed considering their information. Useful elements proceed to process and useless elements are removed from the process to reduce the consuming time. Neighbor pixels with close intensities are assigned in one contour and differences in intensities determine boundaries. The results are then verified by conducting experimental tests. An experimental setup is performed using ice samples and a thermal camera. To observe the created ice contour by the thermal camera, the samples, which are initially at -20° C, are contacted with a warmer surface. Pictures are captured for 20 seconds. The method is applied to five images ,which are captured at the time intervals of 5 seconds. The study shows the green image element carries no useful information; therefore, the boundary detection method is applied on red and blue image elements. In this case study, the results indicate that proposed algorithm shows the boundaries more effective than other edges detection methods such as Sobel and Canny. Comparison between the contour detection in this method and temperature analysis, which states real boundaries, shows a good agreement. This color image edge detection method is applicable to other similar cases according to their image properties.

Keywords: color image processing, edge detection, ice contour boundary, salt ice, thermal image

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1686 Pressure Regulator Optimization in LPG Fuel Injection Systems

Authors: M. Akif Ceviz, Alirıza Kaleli, Erdoğan Güner

Abstract:

LPG pressure regulator is a device which is used to change the phase of LPG from liquid to gas by decreasing the pressure. During the phase change, it is necessary to supply the latent heat of LPG to prevent excessive low temperature. Engine coolant is circulated in the pressure regulator for this purpose. Therefore, pressure regulator is a type of heat exchanger that should be designed for different engine operating conditions. The design of the regulator should ensure that the flow of LPG is in gaseous phase to the injectors during the engine steady state and transient operating conditions. The pressure regulators in the LPG gaseous injection systems currently used can easily change the phase of LPG, however, there is no any control on the LPG temperature in conventional LPG injection systems. It is possible to increase temperature excessively. In this study, a control unit has been tested to keep the LPG temperature in a band. Result of the study showed that the engine performance characteristics can be increased by using the system.

Keywords: temperature, pressure regulator, LPG, PID

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1685 Cytotoxic Drugs: Handling Practices and Clinical Manifestations among Hospital Staff

Authors: Boularas El-Alia, Arbi Raja, Bachir Bouiadjra Sara, Rezk-Kallah Haciba, Rezkkallah Baghdad

Abstract:

Objectives : To determine the handling practices of cytotoxic drugs and to describe clinical manifestations expressed by hospital personnel of Sidi Bel Abbes during the year 2014. Methods: Sectional descriptive study conducted in 3 center university hospital units (Hematology, Oncology and Urology) and Gynecology of EHS Sidi Bel Abbes. A questionnaire was administered to hospital workers regulary exposed to cytotoxic drugs. A work-place visit was performed to have an overview about working conditions. The Cytotoxic Contact Index (CCI) was calculated for each nurse on a period of 15 working days. Treatment of the results was done using SPSS software. Results: The survey reveals that 22 men and 58 women are exposed to cytotoxic drugs for an average of 7 years. Many symptoms such as ocular irritation (38,75%), throat irritation (56,25%), headache (68,75%), dizziness (43,75%), nausea (37,5%), metallic taste (30%), were reported with high frequency. Are noted in the offspring, 3 congenital anomalies,2 diaphragmatic hernia and a cleft palate. The Cytotoxic Contact Index (CCI) was higher than 3 among Oncology nurses and higher than 1 for most of the nurses of Hematology and Gynecology service. The wearing of personal protective clothing was not respected by all workers: (22/23) wear gloves and (20/23) wear a mask,(5/23) wear a cap, (2/23) wear glasses. Only 3 nurses have benefited from continuous training on handling cytotoxic drugs. Conclusion: This study shows a high occupational exposure risk to cytotoxic drugs among persons handling these drugs and the necessity to apply rigorously all measures related to personal protection awareness and training of personnel to minimize these exposure.

Keywords: cytotoxic drugs, handling, clinical manifestations, hospital staff

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1684 Fabrication of Durable and Renegerable Superhydrophobic Coatings on Metallic Surfaces for Potential Industrial Applications

Authors: Priya Varshney, Soumya S. Mohapatra

Abstract:

Fabrication of anti-corrosion and self-cleaning superhydrophobic coatings for metallic surfaces which are regenerable and durable in the aggressive conditions has shown tremendous interest in materials science. In this work, the superhydrophobic coatings on metallic surfaces (aluminum, steel, copper) were prepared by two-step and one-step chemical etching process. In two-step process, roughness on surface was created by chemical etching and then passivation of roughened surface with low surface energy materials whereas, in one-step process, roughness on surface by chemical etching and passivation of surface with low surface energy materials were done in a single step. Beside this, the effect of etchant concentration and etching time on wettability and morphology was also studied. Thermal, mechanical, ultra-violet stability of these coatings were also tested. Along with this, regeneration of coatings and self-cleaning, corrosion resistance and water repelling characteristics were also studied. The surface morphology shows the presence of a rough microstuctures on the treated surfaces and the contact angle measurements confirms the superhydrophobic nature. It is experimentally observed that the surface roughness and contact angle increases with increase in etching time as well as with concentration of etchant. Superhydrophobic surfaces show the excellent self-cleaning behaviour. Coatings are found to be stable and maintain their superhydrophobicity in acidic and alkaline solutions. Water jet impact, floatation on water surface, and low temperature condensation tests prove the water-repellent nature of the coatings. These coatings are found to be thermal, mechanical and ultra-violet stable. These durable superhydrophobic metallic surfaces have potential industrial applications.

Keywords: superhydrophobic, water-repellent, anti-corrosion, self-cleaning

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1683 Molecular Detection of Tuberculosis in Dogs in the Three North-Eastern States Assam, Mizoram and Nagaland of India

Authors: A. G. Barua, Uttam Rajkhowa, Pranjal Moni Nath, Nur Abdul Kadir

Abstract:

Mycobacterium tuberculosis (MTB) is one of the most closely-related intracellular bacterial pathogens, grouped as the M. tuberculosis complex (MTC). MTB, the primary agent of human tuberculosis (TB), can develop clinical TB in animals as 75 percent of canine mycobacterial infection is caused by close contact with an infected human being. In the present study, molecular detection of TB in dogs in three North-eastern states of India, Assam Mizoram, and Nagaland was carried out. So far, there has been a lack of systematic study in these regions, hampered by slow diagnostic methods and poor infrastructure. In an attempt to rectify this situation, molecular epidemiology was carried out for nine months to detect canine TB in a sample of 340 dogs. Isolation of DNA was done with swabs (throat/nasal), nodules of lungs and fluids from 100 suspected dogs and the molecular study were carried out with the help of conventional and real-time PCR. Post-mortem study was also carried out. Our results showed that the prevalence of clinical TB in dogs from a high-risk setting was 1 percent. However, the prevalence of immunological sensitization to M. tuberculosis antigen in dogs living in contact with sputum smeared positive TB cases was almost 50 percent. The latter setting had the maximum impact in terms of TB transmission. During the study period, a survey with a standard questionnaire was carried out in the TB hospitals to study reverse zoonosis. It was observed that an infected human being was one of the major risk factors for dogs to contract the infection. This observation was drawn by examining the probable airborne transmission from humans to their pets or strays. The present study helped to discover the nuances of TB transmission more clearly and systematically as compared to other sporadic tests to detect MTB in canine.

Keywords: Assam and Nagaland, canine TB, India, molecular detection, tuberculosis

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1682 Application of a SubIval Numerical Solver for Fractional Circuits

Authors: Marcin Sowa

Abstract:

The paper discusses the subinterval-based numerical method for fractional derivative computations. It is now referred to by its acronym – SubIval. The basis of the method is briefly recalled. The ability of the method to be applied in time stepping solvers is discussed. The possibility of implementing a time step size adaptive solver is also mentioned. The solver is tested on a transient circuit example. In order to display the accuracy of the solver – the results have been compared with those obtained by means of a semi-analytical method called gcdAlpha. The time step size adaptive solver applying SubIval has been proven to be very accurate as the results are very close to the referential solution. The solver is currently able to solve FDE (fractional differential equations) with various derivative orders for each equation and any type of source time functions.

Keywords: numerical method, SubIval, fractional calculus, numerical solver, circuit analysis

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1681 Seroprevalence Study of Cystic Echinococcosis and Its Associated Risk Factors in Fars Province, Southern Iran

Authors: Mahmoud Reza Tahamtan, Mohammad Saleh Bahreini

Abstract:

Background and Purpose: Cystic echinococcosis, caused by the larval stage of Echinococcus granulosus, is a common parasitic infection of humans and is endemic in many parts of the world, including Iran. So that, one percent of those admitted to surgery departments are hydatid cyst patients, and using the ELISA method, the infection rate has been reported in different regions of Iran from 1.2% to 21.4%. Therefore, the aim of this study was to investigate the seroepidemiology of human hydatid cysts in Fars province, southern Iran, by ELISA method. Methods: In this cross-sectional study, 600 serum samples of persons who were referred to the laboratory of Nemazi Hospital in Shiraz for normal tests were examined for the presence of specific Anti-IgG antibodies to hydatid cysts by ELISA method. During the sampling, a structured questionnaire was used to obtain social data of individuals with determinants of risk factors for Cystic echinococcosis. Finally, the results of the ELISA test, along with demographic information completed by individuals, were analyzed using SPSS software. Results: The average age of the subjects in this study was 40.01 ± 9.166. The prevalence of hydatidosis was reported as 5.66% (34/600). The disease was more in the age group of 21-30, people living in villages, working in rural areas, and people with a history of other parasitic diseases. Statistically, a significant difference was observed between the prevalence of the disease and two risk factors, contact with dogs (OR= 0.042; 95%CI: 0.014-0.12; P= 0.001) and washing vegetables with water (OR= 0.08; 95%CI: 0.011-0.56; P= 0.012). Conclusion: The present study showed that hydatid cyst disease has a significant prevalence in this area. Also, based on the results, contact with dogs and not properly washing vegetables are two important factors of disease transmission.

Keywords: Echinococcus granulosus, Cystic echinococcosis, hydatid cyst, Fars province

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1680 PTFE Capillary-Based DNA Amplification within an Oscillatory Thermal Cycling Device

Authors: Jyh J. Chen, Fu H. Yang, Ming H. Liao

Abstract:

This study describes a capillary-based device integrated with the heating and cooling modules for polymerase chain reaction (PCR). The device consists of the reaction polytetrafluoroethylene (PTFE) capillary, the aluminum blocks, and is equipped with two cartridge heaters, a thermoelectric (TE) cooler, a fan, and some thermocouples for temperature control. The cartridge heaters are placed into the heating blocks and maintained at two different temperatures to achieve the denaturation and the extension step. Some thermocouples inserted into the capillary are used to obtain the transient temperature profiles of the reaction sample during thermal cycles. A 483-bp DNA template is amplified successfully in the designed system and the traditional thermal cycler. This work should be interesting to persons involved in the high-temperature based reactions and genomics or cell analysis.

Keywords: polymerase chain reaction, thermal cycles, capillary, TE cooler

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1679 Operative Technique of Glenoid Anteversion Osteotomy and Soft Tissue Rebalancing for Brachial Plexus Birth Palsy

Authors: Michael Zaidman, Naum Simanovsky

Abstract:

The most of brachial birth palsies are transient. Children with incomplete recovery almost always develop an internal rotation and adduction contracture. The muscle imbalance around the shoulder results in glenohumeral joint deformity and functional limitations. Natural history of glenohumeral deformity is it’s progression with worsening of function. Anteversion glenoid osteotomy with latissimus dorsi and teres major tendon transfers could be an alternative procedure of proximal humeral external rotation osteotomy for patients with severe glenohumeral dysplasia secondary to brachial plexus birth palsy. We will discuss pre-operative planning and stepped operative technique of the procedure on clinical example.

Keywords: obstetric brachial plexus palsy, glenoid anteversion osteotomy, tendon transfer, operative technique

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1678 The Three-Dimensional Kinematics of the Sprint Start in Young Elite Sprinters

Authors: Saeed Ilbeigi, Bart Van Gheluwe

Abstract:

The purpose of this study was to identify the three-dimensional kinematics of the sprint start during the start phase of the sprint. The purpose of this study was to identify the three-dimensional kinematics of the sprint start during the start phase of the sprint. Moreover, the effect of anthropometrical factors such as skeletal muscle mass, thigh girth, and calf girth also were considered on the kinematics of the sprint start. Among all young sprinters involved in the national Belgium league, sixty sprinters (boys: 14.7 ± 1.8 years and girls: 14.8±1.5 years) were randomly selected. The kinematics data of the sprint start were collected with a Vicon® 620 motion analysis system equipped with 12 infrared cameras running at 250 Hz and running the Vicon Data Station software. For statistical analysis, T-tests and ANOVA׳s with Scheffé post hoc test were used and the significant level was set as p≤0.05. The results showed that the angular positions of the lower joints of the young sprinters in the set position were comparable with adult figures from literature, however, with a greater range of joint extension. The most significant difference between boys and girls was found in the set position, where the boys presented a more dorsiflexed ankle. No further gender effect was observed during the leaving the blocks and contact phase. The sprinters with a higher age, skeletal muscle mass, thigh girth, and calf girth displayed a better angular position of the lower joints (e.g. ankle, knee, hip) in the set position, a more optimal angular position for the foot and knee for absorbing impact forces at foot contact and finally a higher range of flexion/extension motion to produce force and power when leaving the blocks.

Keywords: anthropometry, kinematics, sprint start, young elite sprinters

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1677 Remembering and Forgetting in Shakespeare Sonnets

Authors: Nasreddin Bushra Ahmed

Abstract:

Humans use language to externalize their mental perceptions and conceptions and thereby set up an interdependent consciousness about the concrete and abstract spheres of their existence. Language also represents a recording device whereby they capture the transient moment in their lives. Literature with it its various manifestations help keep the individual and collective memories alive. Works of the English literature’s prototypical figure, William Shakespeare provides the best illustration of this fact. Shakespeare’s sonnets abound in prescient insights about the intricacies of human relations. Though they have been the concern of scholars’ investigations for centuries, many of their thematic potentialities are yet to be tapped. The present study aspires to highlight the theme of remembering and forgetting in some of these sonnets as reverse faces of the same coin. Using close reading it is intended to demonstrate how Shakespeare, through imagery and literary tropes, plays with the issues of mortality and immortality, and how he has reaffirmed that literature can provide a locus for perennial presence despite the temporariness of individuals’ existence.

Keywords: forgetting, immortality, literature, remembering, Shakespeare, sonnet

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1676 Influence of Magnetic Field on the Antibacterial Properties of Pine Oil

Authors: Dawid Sołoducha, Tomasz Borowski, Agata Markowska-Szczupak, Aneta Wesołowska, Marian Kordas, Rafał Rakoczy

Abstract:

Many studies report varied effects of the magnetic field in medicine, but applications are still missing. Also, essential oils (EOs) were historically used in healing therapies, food preservation and the cosmetic industry due to their wound healing and antioxidant properties and antimicrobial activity. Unfortunately, the chemical characterization of EOs activates its antibacterial action only at a fairly high concentration. They can cause skin reactions, e.g., irritation (irritant contact dermatitis) or allergic contact dermatitis; therefore, they should always be used with caution. However, the administration of EOs to achieve the desired antimicrobial activity and stability with long-term medical usage in low concentration is challenging. The aim of this work was to investigate the antimicrobial activity of commercial Pinus sylvestris L. essential oil from Polish company Avicenna-Oil® under Rotating Magnetic Field (RMF) at f = 1 – 50 Hz. The novel construction of the magnetically assisted self-constructed reactor (MAP) was applied for this study. The chemical composition of essential pine oil was determined by gas chromatography coupled with mass spectrometry (GC-MS). Model bacteria Escherichia coli K12 (ATCC 25922) was used. Different concentrations of pine oil was prepared: 100% 50%, 25%, 12.5% and 6.25%. The disc diffusion and MIC test were done. To examine the effect of essential pine oil and rotating magnetic field RMF on antibacterial performance agar plate method was used. Pine oil consist of α-pinene (28.58%), β-pinene (17.79%), δ-3-carene (14.17%) and limonene (11.58%). The present study indicates the exposition to the RMF, as compared to the unexposed controls causing an increase in the efficacy of antibacterial properties of pine oil. We have shown that the rotating magnetic fields (RMF) at a frequency, f, between 25 Hz to 50 Hz, increase the antimicrobial efficiency of oil at lower than 50% concentration. The new method can be applied in many fields e.g. aromatherapy, medicine as a component of dressing, or as food preservatives.

Keywords: rotating magnetic field, pine oil, antimicrobial activity, Escherichia coli

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1675 Evaluation of Chitin Filled Epoxy Coating for Corrosion Protection of Q235 Steel in Saline Environment

Authors: Innocent O. Arukalam, Emeka E. Oguzie

Abstract:

Interest in the development of eco-friendly anti-corrosion coatings using bio-based renewable materials is gaining momentum recently. To this effect, chitin biopolymer, which is non-toxic, biodegradable, and inherently possesses anti-microbial property, was successfully synthesized from snail shells and used as a filler in the preparation of epoxy coating. The chitin particles were characterized with contact angle goniometer, scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectrophotometer, and X-ray diffractometer (XRD). The performance of the coatings was evaluated by immersion and electrochemical impedance spectroscopy (EIS) tests. Electronic structure properties of the coating ingredients and molecular level interaction of the corrodent and coated Q235 steel were appraised by quantum chemical computations (QCC) and molecular dynamics (MD) simulation techniques, respectively. The water contact angle (WCA) measurement of chitin particles was found to be 129.3o while that of chitin particles modified with amino trimethoxy silane (ATMS) was 149.6o, suggesting it is highly hydrophobic. Immersion and EIS analyses revealed that epoxy coating containing silane-modified chitin exhibited lowest water absorption and highest barrier as well as anti-corrosion performances. The QCC showed that quantum parameters for the coating containing silane-modified chitin are optimum and therefore corresponds to high corrosion protection. The high negative value of adsorption energies (Eads) for the coating containing silane-modified chitin indicates the coating molecules interacted and adsorbed strongly on the steel surface. The observed results have shown that silane-modified epoxy-chitin coating would perform satisfactorily for surface protection of metal structures in saline environment.

Keywords: chitin, EIS, epoxy coating, hydrophobic, molecular dynamics simulation, quantum chemical computation

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1674 Development and Characterization of Castor Oil-Based Biopolyurethanes for High-Performance Coatings and Waterproofing Applications

Authors: Julie Anne Braun, Leonardo D. da Fonseca, Gerson C. Parreira, Ricardo J. E. Andrade

Abstract:

Polyurethanes (PU) are multifunctional polymers used across various industries. In construction, thermosetting polyurethanes are applied as coatings for flooring, paints, and waterproofing. They are widely specified in Brazil for waterproofing concrete structures like roof slabs and parking decks. Applied to concrete, they form a fully adhered membrane, providing a protective barrier with low water absorption, high chemical resistance, impermeability to liquids, and low vapor permeability. Their mechanical properties, including tensile strength (1 to 35 MPa) and Shore A hardness (83 to 88), depend on resin molecular weight and functionality, often using Methylene diphenyl diisocyanate. PU production, reliant on fossil-derived isocyanates and polyols, contributes significantly to carbon emissions. Sustainable alternatives, such as biopolyurethanes from renewable sources, are needed. Castor oil is a viable option for synthesizing sustainable polyurethanes. As a bio-based feedstock, castor oil is extensively cultivated in Brazil, making it a feasible option for the national market and ranking third internationally. This study aims to develop and characterize castor oil-based biopolyurethane for high-performance waterproofing and coating applications. A comparative analysis between castor oil-based PU and polyether polyol-based PU was conducted. Mechanical tests (tensile strength, Shore A hardness, abrasion resistance) and surface properties (contact angle, water absorption) were evaluated. Thermal, chemical, and morphological properties were assessed using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The results demonstrated that both polyurethanes exhibited high mechanical strength. Specifically, the tensile strength for castor oil-based PU was 19.18 MPa, compared to 12.94 MPa for polyether polyol-based PU. Similarly, the elongation values were 146.90% for castor oil-based PU and 135.50% for polyether polyol-based PU. Both materials exhibited satisfactory performance in terms of abrasion resistance, with mass loss of 0.067% for castor oil PU and 0.043% for polyether polyol PU and Shore A hardness values of 89 and 86, respectively, indicating high surface hardness. The results of the water absorption and contact angle tests confirmed the hydrophilic nature of polyether polyol PU, with a contact angle of 58.73° and water absorption of 2.53%. Conversely, the castor oil-based PU exhibited hydrophobic properties, with a contact angle of 81.05° and water absorption of 0.45%. The results of the FTIR analysis indicated the absence of a peak around 2275 cm-1, which suggests that all of the NCO groups were consumed in the stoichiometric reaction. This conclusion is supported by the high mechanical test results. The TGA results indicated that polyether polyol PU demonstrated superior thermal stability, exhibiting a mass loss of 13% at the initial transition (around 310°C), in comparison to castor oil-based PU, which experienced a higher initial mass loss of 25% at 335°C. In summary, castor oil-based PU demonstrated mechanical properties comparable to polyether polyol PU, making it suitable for applications such as trafficable coatings. However, its higher hydrophobicity makes it more promising for watertightness. Increasing environmental concerns necessitate reducing reliance on non-renewable resources and mitigating the environmental impacts of polyurethane production. Castor oil is a viable option for sustainable polyurethanes, aligning with emission reduction goals and responsible use of natural resources.

Keywords: polyurethane, castor oil, sustainable, waterproofing, construction industry

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