Search results for: eye contact

Authors: Xing Wang, Lin Feng, Lingling E., Hongchen Liu

Abstract:

In patients with type 2 diabetes mellitus (DM) there is poorer quality osseointegration than in non-diabetic (n-DM) patients, and the success of dental implants is less. Recent studies have demonstrated that insulin could stimulate bone cells to produce and accelerate implant osseointegration in DM patients.This raised the question whether insulin could provide local bone anabolic effects in non-diabetic patients. In this study,48 SD rats were divided into four groups randomly: DM group, DM+insulin group, n-DM group, n-DM + insulin group. All rats were implanted the titanium implant near the epiphyseal end of tibia, then the DM + insulin and n-DM + insulin group received twice-daily subcutaneous injections of insulin (10U/day).Two,four and eight weeks after implantation, rats were killed in batches. Histomorphometry and immunohistochemistry were used to evaluate bone formation and osseointegration. The amount of newly formed bone, Implant–bone contact and the expression of OCN,RUNX2 in the DM+insulin, n-DM and n-DM+insulin group were significantly more than in the DM group (p<0.05). Compared with the n-DM group,the Implant–bone contact and expression of OCN,RUNX2 were significantly increased in n-DM+insulin group (p< 0.05). Taken together,these observations provide evidence that insulin has the potential to increase bone formation and osseointegration around implant not only in diabetic subjects but also in non-diabetic subject.

Keywords: insulin, diabetes mellitus, osseointegration, dental implants

Procedia PDF Downloads 464

Authors: Shahroz Khan, Osman Taha Şen

Abstract:

In automotive brake systems, brake noise has been a major problem, and brake squeal is one of the critical ones which is an instability issue. The brake squeal produces an audible sound at high frequency that is irritating to the human ear. To study this critical problem, first a nonlinear mathematical model with three degree of freedom is developed. This model consists of a point mass that simulates the brake pad and a sliding surface that simulates the brake rotor. The model exposes kinematic and clearance nonlinearities, but no friction nonlinearity. In the formulation, the friction coefficient is assumed to be constant and the friction force does not change direction. The nonlinear governing equations of the model are first obtained, and numerical solutions are sought for different cases. Second, a computational model for the squeal problem is developed with a commercial software, and computational solutions are obtained with two different types of contact cases (solid-to-solid and sphere-to-plane). This model consists of three rigid bodies and several elastic elements that simulate the key characteristics of a brake system. The response obtained from this model is compared with numerical solutions in time and frequency domain.

Keywords: contact force, nonlinearities, brake squeal, vehicle brake

Procedia PDF Downloads 246

Authors: A. Al-Juboori, D. Wexler, H. Li, H. Zhu, C. Lu, A. McCusker, J. McLeod, S. Pannila, Z. Wang

Abstract:

Squats are a type railhead defect related to rolling contact fatigue (RCF) damage and are considered serious problem affecting a wide range of railway networks across the world. Squats can lead to partial or complete rail failure. Formation mechanics of squats on the surface of rail steel is still a matter of debate. In this work, structural and microstructural observations from ex-service damaged rail both confirms the phases present in white etching layer (WEL) regions and relationship between cracking in WEL and squat defect formation. XRD synchrotron results obtained from the top surfaces of rail regions containing both WEL and squat defects reveal that these regions contain both martensite and retained austenite. Microstructural analysis of these regions revealed the occurrence cracks extending from WEL down into the rail through the squat region. These findings obtained from field rail specimen support the view that WEL contains regions of austenite and martensitic transformation product, and that cracks in this brittle surface layer propagate deeper into the rail as squats originate and grow.

Keywords: squat, white etching layer, rolling contact fatigue, synchrotron diffraction

Procedia PDF Downloads 331

Authors: Ali Ahmed Ali Al-Juboori, H. Zhu, D. Wexler, H. Li, C. Lu, J. McLeod, S. Pannila, J. Barnes

Abstract:

A number of studies have focused on the formation mechanics of white etching layer and its origin in the railway operation. Until recently, the following hypotheses consider the precise mechanics of WELs formation: (i) WELs are the result of thermal process caused by wheel slip; (ii) WELs are mechanically induced by severe plastic deformation; (iii) WELs are caused by a combination of thermo-mechanical process. The mechanisms discussed above lead to occurrence of white etching layers on the area of wheel and rail contact. This is because the contact patch which is the active point of the wheel on the rail is exposed to highest shear stresses which result in localised severe plastic deformation; and highest rate of heat caused by wheel slipe during excessive traction or braking effort. However, if the WELs are not on the running band area, it would suggest that there is another cause of WELs formation. In railway system, particularly electrified railway, arcing phenomenon has been occurring more often and regularly on the rails. In electrified railway, the current is delivered to the train traction motor via contact wires and then returned to the station via the contact between the wheel and the rail. If the contact between the wheel and the rail is temporarily losing, due to dynamic vibration, entrapped dirt or water, lubricant effect or oxidation occurrences, high current can jump through the gap and results in arcing. The other resources of arcing also include the wheel passage the insulated joint and lightning on a train during bad weather. During the arcing, an extensive heat is generated and speared over a large area of top surface of rail. Thus, arcing is considered another heat source in the rail head (rather than wheel slipe) that results in microstructural changes and white etching layer formation. A head hardened (HH) rail steel, cut from a curved rail truck was used for the investigation. Samples were sectioned from a depth of 10 mm below the rail surface, where the material is considered to be still within the hardened layer but away from any microstructural changes on the top surface layer caused by train passage. These samples were subjected to electrical discharges by using Gas Tungsten Arc Welding (GTAW) machine. The arc current was controlled and moved along the samples surface in the direction of travel, as indicated by an arrow. Five different conditions were applied on the surface of the samples. Samples containing pre-existed WELs, taken from ex-service rail surface, were also considered in this study for comparison. Both simulated and ex-serviced WELs were characterised by advanced methods including SEM, TEM, TKD, EDS, XRD. Samples for TEM and TKFD were prepared by Focused Ion Beam (FIB) milling. The results showed that both simulated WELs by electrical arcing and ex-service WEL comprise similar microstructure. Brown etching layer was found with WELs and likely induced by a concurrent tempering process. This study provided a clear understanding of new formation mechanics of WELs which contributes to track maintenance procedure.

Keywords: white etching layer, arcing, brown etching layer, material characterisation

Procedia PDF Downloads 121

Authors: Víctor Martínez del Rey, Kourosh Nasr Esfahani, Amir Masoud Samani Majd

Abstract:

In this experimental study, the behaviors of Mixed Oxidant solution components (MOS) and sodium hypochlorite (HYPO) as the most commonly applied surface disinfectant were compared through the effectiveness of chlorine disinfection as a function of the contact time and residual chlorine. In this regard, the variation of pH, free available chlorine (FAC) concentration, and electric conductivity (EC) of disinfection solutions in different concentrations were monitored over 48 h contact time. In parallel, the plant stress activated by chlorine-based disinfectants was assessed by comparing MOS and HYPO. The elements of pH and EC in the plant-soil and their environmental impacts, spread by disinfection solutions were analyzed through several concentrations of FAC including 500 mg/L, 1000 mg/L, and 5000 mg/L in irrigated water. All the experiments were carried out at the service station of Sant Cugat, Spain. The outcomes indicated lower pH and higher durability of MOS than HYPO at the same concentration of FAC which resulted in promising stability of FAC within MOS. Furthermore, the pH and EC value of plant-soil irrigated by NaOCl solution were higher than that of MOS solution at the same FAC concentration. On-site generation of MOS as a safe chlorination option might be considered an imaginary future of smart cities.

Keywords: disinfection, free available chlorine, on-site generation, sodium hypochlorite

Procedia PDF Downloads 118

Authors: Alvyra Galkienė, Ona Monkevičienė

Abstract:

The full participation of all pupils in the overall educational process is defined by the concept of inclusive education, which is gradually evolving in education policy and practice. It includes the full participation of all pupils in a shared learning experience and educational practices that address barriers to learning. Inclusive education applying the principles of Universal Design for Learning (UDL), which includes promoting students' involvement in learning processes, guaranteeing a deep understanding of the analysed phenomena, initiating self-directed learning, and using e-tools to create a barrier-free environment, is a prerequisite for the personal success of each pupil. However, the sustainability of quality education is affected by the transformation of education systems. This was particularly evident during the period of the forced transition from contact to distance education in the COVID-19 pandemic. Research Problem: The transformation of the educational environment from real to virtual one and the loss of traditional forms of educational support highlighted the need for new research, revealing the individual profiles of teachers using UDL-based learning and the pathways of sustainable transfer of successful practices to non-conventional learning environments. Research Methods: In order to identify individual latent teacher profiles that encompass the essential components of UDL-based inclusive teaching and direct leadership of students' learning, the quantitative analysis software Mplius was used for latent profile analysis (LPA). In order to reveal proven, i.e., sustainable, pathways for the transit of the components of UDL-based inclusive learning to distance learning, latent profile transit analysis (LPTA) via Mplius was used. An online self-reported questionnaire was used for data collection. It consisted of blocks of questions designed to reveal the experiences of subject teachers in contact and distance learning settings. 1432 Lithuanian, Latvian, and Estonian subject teachers took part in the survey. Research Results: The LPA analysis revealed eight latent teacher profiles with different characteristics of UDL-based inclusive education or traditional teaching in contact teaching conditions. Only 4.1% of the subject teachers had a profile characterised by a sustained UDL approach to teaching: promoting pupils' self-directed learning; empowering pupils' engagement, understanding, independent action, and expression; promoting pupils' e-inclusion; and reducing the teacher's direct supervision of the students. Other teacher profiles were characterised by limited UDL-based inclusive education either due to the lack of one or more of its components or to the predominance of direct teacher guidance. The LPTA analysis allowed us to highlight the following transit paths of teacher profiles in the extreme conditions of the transition from contact to distance education: teachers staying in the same profile of UDL-based inclusive education (sustainable transit) or jumping to other profiles (unsustainable transit in case of barriers), and teachers from other profiles moving to this profile (ongoing transit taking advantage of the changed new possibilities in the teaching process).

Keywords: distance education, latent teacher profiles, sustainable transit, UDL

Procedia PDF Downloads 101

Authors: Amin Ardali, Mohammadreza Khalili, Mohammadreza Rezai

Abstract:

In this paper, dynamic response of thin smart composite panel subjected to low-velocity transverse impact is investigated. Shape memory wires are used to reinforced curved composite panel in a smart way. One-dimensional thermodynamic constitutive model by Liang and Rogers is used for estimating the structural recovery stress. The two degrees-of-freedom mass-spring model is used for evaluation of the contact force between the curved composite panel and the impactor. This work is benefited from the Hertzian linear contact model which is linearized for the impact analysis of curved composite panel. The governing equations of curved panel are provided by first-order shear theory and solved by Fourier series related to simply supported boundary condition. For this purpose, the equation of doubly curved panel motion included the uniform in-plane forces is obtained. By the present analysis, the curved panel behavior under low-velocity impact, and also the effect of the impact parameters, the shape memory wire and the curved panel dimensions are studied.

Keywords: doubly curved shell, SMA wire, impact response, smart material, shape memory alloy

Procedia PDF Downloads 405

Authors: M. S. Mahmoud

Abstract:

This study was conducted to evaluate the manganese removal from aqueous solution using Banana peels activated carbon (BPAC). Batch experiments have been carried out to determine the influence of parameters such as pH, biosorbent dose, initial metal ion concentrations and contact times on the biosorption process. From these investigations, a significant increase in percentage removal of manganese 97.4 % is observed at pH value 5.0, biosorbent dose 0.8 g, initial concentration 20 ppm, temperature 25 ± 2 °C, stirring rate 200 rpm and contact time 2 h. The equilibrium concentration and the adsorption capacity at equilibrium of the experimental results were fitted to the Langmuir and Freundlich isotherm models; the Langmuir isotherm was found to well represent the measured adsorption data implying BPAC had heterogeneous surface. A raw groundwater samples were collected from Baharmos groundwater treatment plant network at Embaba and Manshiet Elkanater City/District-Giza, Egypt, for treatment at the best conditions that reached at first phase by BPAC. The treatment with BPAC could reduce iron and manganese value of raw groundwater by 91.4 % and 97.1 %, respectively and the effect of the treatment process on the microbiological properties of groundwater sample showed decrease of total bacterial count either at 22°C or at 37°C to 85.7 % and 82.4 %, respectively. Also, BPAC was characterized using SEM and FTIR spectroscopy.

Keywords: biosorption, banana peels, isothermal models, manganese

Procedia PDF Downloads 369

Authors: Gabriella Zarlenga, Martha L. Hall

Abstract:

Introduction: Premature infants are at risk for neurodevelopmental deficits and hospital readmissions, which can increase the financial burden on the health care system and families. Kangaroo care (skin-to-skin contact) is a practice that can improve preterm infant health outcomes. Preterm infants can acquire adequate body temperature, heartbeat, and breathing regulation through lying directly on the mother’s abdomen and in between her breasts. Due to some infant’s condition, kangaroo care is not a feasible intervention. The purpose of this proof-of-concept research project is to create a device which simulates skin-to-skin contact for pre-term infants not eligible for kangaroo care, with the aim of promoting baby’s health outcomes, reducing the incidence of serious neonatal and early childhood illnesses, and/or improving cognitive, social and emotional aspects of development. Methods: The study design is a proof-of-concept based on a three-phase approach; (1) observational study and data analysis of the standard of care for 2 groups of pre-term infants, (2) design and concept development of a novel device for pre-term infants not currently eligible for standard kangaroo care, and (3) prototyping, laboratory testing, and evaluation of the novel device in comparison to current assessment parameters of kangaroo care. A single center study will be conducted in an area hospital offering Level III neonatal intensive care. Eligible participants include newborns born premature (28-30 weeks of age) admitted to the NICU. The study design includes 2 groups: a control group receiving standard kangaroo care and an experimental group not eligible for kangaroo care. Based on behavioral analysis of observational video data collected in the NICU, the device will be created to simulate mother’s body using electrical components in a thermoplastic polymer housing covered in silicone. It will be designed with a microprocessor that controls simulated respiration, heartbeat, and body temperature of the 'simulated caregiver' by using a pneumatic lung, vibration sensors (heartbeat), pressure sensors (weight/position), and resistive film to measure temperature. A slight contour of the simulator surface may be integrated to help position the infant correctly. Control and monitoring of the skin-to-skin contact simulator would be performed locally by an integrated touchscreen. The unit would have built-in Wi-Fi connectivity as well as an optional Bluetooth connection in which the respiration and heart rate could be synced with a parent or caregiver. A camera would be integrated, allowing a video stream of the infant in the simulator to be streamed to a monitoring location. Findings: Expected outcomes are stabilization of respiratory and cardiac rates, thermoregulation of those infants not eligible for skin to skin contact with their mothers, and real time mother Bluetooth to the device to mimic the experience in the womb. Results of this study will benefit clinical practice by creating a new standard of care for premature neonates in the NICU that are deprived of skin to skin contact due to various health restrictions.

Keywords: kangaroo care, wearable technology, pre-term infants, medical design

Procedia PDF Downloads 157

Authors: K. M. Saif Ur Rahman, Razib Mamun, Himica Arjuman, Fida Al Shams

Abstract:

Introduction: Autism spectrum disorder (ASD) has become an emerging neurodevelopmental disorder with increasing prevalence. It has become an important public health issue globally. Many approaches including speech and language therapy (SLT), occupational therapy, behavioral therapy etc. are being applied for the betterment of the ASD patients. This study aims to describe the characteristics of ASD patients and perception of caregiver regarding SLT in Bangladesh. Methods: This cross-sectional study was conducted in a therapy and rehabilitation center at Dhaka city. Caregivers of 48 ASD patients responded regarding their perception of SLT and characteristics of patients. Results: Among 48 ASD patients, 56.3% were between 3 to 5 years age group with a male predominance (87.5%). More than half of the participants (56.3%) initiated SLT at the age of 1-3 years and the majority (43.8%) were taking SLT for less than 1 year. Majority of the patients (64.6%) were taken to a physician for healthcare as a first contact of which 29.2% were referred to SLT by physicians. More than half (56.3%) of the caregivers were moderately satisfied with SLT and most of them (62.5%) mentioned moderate improvement through SLT. Improvement rate was 10-15% in specific symptoms such as eye contact, complex mannerism, pointing, imitation etc. Conclusion: This study reveals the self-reported perception of caregivers on SLT. Despite reported improvements, more exploration of different approaches and intervention for management of ASD is recommended.

Keywords: ASD, characteristics, SLT, Bangladesh

Procedia PDF Downloads 181

Authors: M. Van Zyl, M. H. A. Combrinck, E. J. Spamer

Abstract:

Due to the need for higher education in South Africa, the country experiences a rapid growth in open distance learning, especially in rural areas. It is difficult for people to enrol fulltime at contact universities, owing to work and financial constraints. The Unit for Open Distance Learning (UODL) at the North-West University (NWU), Potchefstroom campus, South Africa was established in 2013 with its main function to deliver open distance learning programmes to 30 000 students from the Faculties of Education Sciences, Theology and Health Sciences. With the use of interactive whiteboards (IWBs), the NWU and UODL are now able to deliver lectures to students concurrently at 60 regional open learning centres across Southern Africa as well as to an unlimited number of individuals with Internet access worldwide. Although IWBs are not new, our initiative is to use them more extensively in order to create more contact between lecturers and students. To be able to ensure and enhance quality education it is vital to determine students’ perceptions on the delivery of programmes by means of IWBs. Therefore, the aim of the study is to explore students’ perceptions for the use of IWBs in the delivery of programmes in terms of Moore’s Theory of Transactional Distance.

Keywords: interactive white board, open distance learning, technology, transactional learning

Procedia PDF Downloads 454

Authors: Mohamed A. Mohamed-Ali, Jannis Simos, Khalid M. Kheiralla

Abstract:

The Ingessana hills in the southern Blue Nile of Sudan are part of the southern sector of the NE-SW trending ophiolithic belt of the Arab-Nubian Shield with mid-neoproterozoic age. The rocks are mainly serpentinized and in parts highly silicified dunites especially towards the contact with the intruding Bau granite. A promising chromite mineralization zones in the area tend to be generally associated with NE-SW trending shear-zones. A detailed geophysical survey employing electrical resistivity tomography (ERT) at 34 lines were carried out over a zone of a known chromite mineralization to test feasibility of detecting and delineating the ore (if exist) and accordingly facilitate the positioning of exploratory drill holes. ERT sections were inverted with smooth constraints inversion code where the contacts between the granite and the ultramafics are showing up clearly. The continuity of mineralization along the contact is not well confirmed. However, the low-resistivity anomalies are probably recognized as potential chromite mineralization zones. These anomalies represent prime targets for further exploration by drilling, trenching or shallow pits. If the results of the drilling or excavations are positive, small open pit exploitations may produce important tonnages of chromite.

Keywords: chromite exploration, ERT, Ingessana Hills, inversion

Procedia PDF Downloads 388

Authors: Xu Zhang

Abstract:

This article unveils an indicator of language contact between English and Cantonese in one of the Outer Circle Englishes, Hong Kong (HK) English, through an empirical investigation into 1000 tokens from the Global Web-based English (GloWbE) corpus, employing frequency analysis and logistic regression analysis. It is perceived that Cantonese and general Chinese are contextually marked by an integral underlying thinking pattern. Chinese speakers exhibit a reliance on semantic context over syntactic rules and lexical forms. This linguistic trait carries over to their use of English, affording greater flexibility to formal elements in constructing English sentences. The study focuses on the syntactic positioning of the focusing subjunct ‘also’, a linguistic element used to add new or contrasting prominence to specific sentence constituents. The English language generally allows flexibility in the relative position of 'also’, while there is a preference for close marking relationships. This article shifts attention to Hong Kong, where Cantonese and English converge, and 'also' finds counterparts in Cantonese ‘jaa’ and Mandarin ‘ye’. Employing a corpus-based data-driven method, we investigate the syntactic position of 'also' in both HK and GB English. The study aims to ascertain whether HK English exhibits a greater 'syntactic freedom,' allowing for a more distant marking relationship with 'also' compared to GB English. The analysis involves a random extraction of 500 samples from both HK and GB English from the GloWbE corpus, forming a dataset (N=1000). Exclusions are made for cases where 'also' functions as an additive conjunct or serves as a copulative adverb, as well as sentences lacking sufficient indication that 'also' functions as a focusing particle. The final dataset comprises 820 tokens, with 416 for GB and 404 for HK, annotated according to the focused constituent and the relative position of ‘also’. Frequency analysis reveals significant differences in the relative position of 'also' and marking relationships between HK and GB English. Regression analysis indicates a preference in HK English for a distant marking relationship between 'also' and its focused constituent. Notably, the subject and other constituents emerge as significant predictors of a distant position for 'also.' Together, these findings underscore the nuanced linguistic dynamics in HK English and contribute to our understanding of language contact. It suggests that future pedagogical practice should consider incorporating the syntactic variation within English varieties, facilitating leaners’ effective communication in diverse English-speaking environments and enhancing their intercultural communication competence.

Keywords: also, Cantonese, English, focus marker, frequency analysis, language contact, logistic regression analysis

Procedia PDF Downloads 56

Authors: Van-Dycke Sarpong Asare, Vincent Adongo

Abstract:

Field measurement of subsurface seismic p-wave velocities was undertaken through seismic refraction tomography. The aim of this work is to obtain a model of the shallow subsurface material elastic properties relevant for geotechnical site characterization. The survey area is at Pwalugu in Northern Ghana, where a multipurpose dam, for electricity generation, irrigation, and potable water delivery, is being planned. A 24-channel seismograph and 24, 10 Hz electromagnetic geophones, deployed 5 m apart constituted the acquisition hardware. Eleven (2-D) seismic refraction profiles, nine of which ran almost perpendicular and two parallel to the White Volta at Pwalugu, were acquired. The refraction tomograms of the thirteen profiles revealed a subsurface model consisting of one minor and one major acoustic impedance boundaries – the top dry/loose sand and the variably weathered sandstone contact, and the overburden-sandstones bedrock contact respectively. The p-wave velocities and by inference, with a priori values of poison ratios, the s-wave velocities, assisted in characterizing the geotechnical conditions of the proposed site and also in evaluating the dynamic properties such as the maximum shear modulus, the bulk modulus, and the Young modulus.

Keywords: tomography, characterization, consolidated, Pwalugu and seismograph

Procedia PDF Downloads 129

Authors: S. Ayeko, J. Milton, C. Hughes, K. Anderson, R. G. Middleton

Abstract:

Background: Periprosthetic femoral fractures (PFF) in association with hip hemiarthroplasty or total hip arthroplasty is a common and serious complication. In the Vancouver Classification system algorithm, B1 fractures should be treated with Open Reduction and Internal Fixation (ORIF) and preferentially revised in combination with ORIF if B2 or B3. This study aims to assess patient outcomes after plate osteosynthesis alone for Vancouver B1 and B2 fractures. The main outcome is the 1-year re-revision rate, and secondary outcomes are 30-day and 1-year mortality. Method: This is a retrospective single-centre case-series review from January 2016 to June 2021. Vancouver B1 and B2, non-malignancy fractures in adults over 18 years of age treated with polyaxial Non-Contact Bridging plate osteosynthesis, have been included. Outcomes were gathered from electronic notes and radiographs. Results: There were 50 B1 and 64 B2 fractures. 26 B2 fractures were managed with ORIF and revision, 39 ORIF alone. Of the revision group, one died within 30 days (3.8%), one at one year (3.8%), and two were revised within one year (7.7). Of the B2 ORIF group, three died within 30-day mortality (7.96%), eight at one year (21.1%), and 0 were revised in 1 year. Conclusion: This study has demonstrated that satisfactory outcomes can be achieved with ORIF, excluding revision in the management of B2 fractures.

Keywords: arthroplasty, bridging plate, periprosthetic fracture, revision surgery

Procedia PDF Downloads 101

Authors: Hami-Ziniman Revital, Ashwall Rachelly

Abstract:

The conflict resolution realm has developed tremendously during the last half-decade. Three main approaches should be mentioned: an Alternative Dispute Resolution (ADR) suggesting processes such as Arbitration or Interests-based Negotiation was developed as an answer to obligations and rights-based conflicts. The Pragmatic mediation approach focuses on the gap between interests and needs of disputants. The Transformative mediation approach focusses on relations and suits identity-based conflicts. In the current study, we examine the conflictual relations between religious and non-religious Jews in Israel and the impact of three transformative mechanisms: Inter-group recognition, In-group empowerment and Value-based reframing on the relations between the participants. The research was conducted during four facilitated joint mediation classes. A unique finding was found. Using both transformative mechanisms and the Contact Hypothesis criteria, we identify transformation in participants’ relations and a considerable change from anger, alienation, and suspiciousness to an increased understanding, affection and interpersonal concern towards the out-group members. Intergroup Recognition, In-group empowerment, and Values-based reframing were the skills discovered as the main enablers of the change in the relations and the research participants’ fostered mutual recognition of the out-group values and identity-based issues. We conclude this transformation was possible due to a constant intergroup contact, based on the Contact Hypothesis criteria. In addition, as Interests-based mediation uses “Reframing” as a skill to acknowledge both mutual and opposite needs of the disputants, we suggest the use of “Value-based Reframing” in intergroup identity-based conflicts, as a skill contributes to the empowerment and the recognition of both mutual and different out-group values. We offer to implement those insights and skills to assist conflict resolution facilitators in various intergroup identity-based conflicts resolution efforts and to establish further research and knowledge.

Keywords: empowerment, identity-based conflict, intergroup recognition, intergroup relations, mediation skills, multi-cultural society, reframing, value-based recognition

Procedia PDF Downloads 343

Authors: Phanawan Whangdee, Tomoaki Watanabe, Viritpon Srimaneepong, Dujreutai Pongkao Kashima

Abstract:

The anodized films formed at high current density or high voltage have been widely prepared for dental implant because it can improve the hydrophilicity to the film. Our attempt is exploring whether low current density and low voltage could enhance the good hydrophilicity to the anodized films or not. Furthermore, UV irradiation would be one of the key factor to enhance their hydrophilicity. The anodized films were performed at low current density of 2 mA/cm2 in 1M H3PO4, 1 mA/cm2 in 1M MCPM and low voltage of 6 V in either 1M H3PO4 or 1M MCPM. All samples were treated with UV for various times up to 24 h. After UV irradiation, the contact angle decreased, the chemical species changed. The Ti 2p and O 1s peaks increased, while the C 1s peak decreased which might be due to removal of hydrocarbon. The functional groups of the films shown as the change of OH groups appeared at wave number 3700 cm-1 and 2900-3000 cm-1, however, the peak of H2O at 1630 cm-1disappeared. It is indicated that UV irradiation might change the stretching modes of OH groups coordinated to surface Ti4+ cation but UV did not affect to the changes in surface morphologies. The surface energies increased after UV irradiation resulting in improving of the hydrophilicity. The anodized films formed at low current density or low voltage after UV irradiation showed a low contact angle as well as the film formed at high current density or high voltage.

Keywords: hydrophilicity, low current density, low voltage, UV irradiation

Procedia PDF Downloads 499

Authors: Lavanya Srinivasan

Abstract:

Biometric identification is to identify unique features in a person like fingerprints, iris, ear, and voice recognition that need the subject's permission and physical contact. Gait biometric is used to identify the unique gait of the person by extracting moving features. The main advantage of gait biometric to identify the gait of a person at a distance, without any physical contact. In this work, the gait biometric is used for person re-identification. The person walking naturally compared with the same person walking with bag, coat, and case recorded using longwave infrared, short wave infrared, medium wave infrared, and visible cameras. The videos are recorded in rural and in urban environments. The pre-processing technique includes human identified using YOLO, background subtraction, silhouettes extraction, and synthesis Gait Entropy Image by averaging the silhouettes. The moving features are extracted from the Gait Entropy Energy Image. The extracted features are dimensionality reduced by the principal component analysis and recognised using different classifiers. The comparative results with the different classifier show that linear discriminant analysis outperforms other classifiers with 95.8% for visible in the rural dataset and 94.8% for longwave infrared in the urban dataset.

Keywords: biometric, gait, silhouettes, YOLO

Procedia PDF Downloads 172

Authors: Jun Hyung Lee, Robin B. Guevarra, Jin Ho Cho, Bo-Ra Kim, Jiwon Shin, Doo Wan Kim, Young Hwa Kim, Minho Song, Hyeun Bum Kim

Abstract:

Salmonella is one of the most important swine pathogens, causing acute or chronic digestive diseases, such as enteritis. The acute form of enteritis is common in young pigs of 2-4 months of age. Salmonellosis in swine causes a huge economic burden to swine industry by reducing production. Therefore, it is necessary that swine industries should strive to decrease Salmonellosis in pigs in order to reduce economic losses. Thus, we tested three types of natural plant extracts(PEs) to evaluate antibacterial effects against Salmonella enterica Typhimurium isolated from the piglet with Salmonellosis. Three PEs including turmeric oleoresin (containing curcumin 79 to 85%), capsicum oleoresin (containing capsaicin 40%-40.1%), and garlic essential oil (100% natural garlic) were tested using the direct contact agar diffusion test, minimum inhibitory concentration test, growth curve assay, and heat stability test. The tests were conducted with PEs at each concentration of 2.5%, 5%, and 10%. For the heat stability test, PEs with 10% concentration were incubated at each 4, 20, 40, 60, 80, and 100 °C for 1 hour; then the direct contact agar diffusion test was used. For the positive and negative controls, 0.5N HCl and 1XPBS were used. All the experiments were duplicated. In the direct contact agar diffusion test, garlic essential oil with 2.5%, 5%, and 10% concentration showed inhibit zones of 1.5cm, 2.7cm, and 2.8cm diameters compared to that of 3.5cm diameter for 0.5N HCl. The minimum inhibited concentration of garlic essential oil was 2.5%. Growth curve assay showed that the garlic essential oil was able to inhibit Salmonella growth significantly after 4hours. The garlic essential oil retained the ability to inhibit Salmonella growth after heat treatment at each temperature. However, turmeric and capsicum oleoresins were not able to significantly inhibit Salmonella growth by all the tests. Even though further in-vivo tests will be needed to verify effects of garlic essential oil for the Salmonellosis prevention for piglets, our results showed that the garlic essential oil could be used as a potential natural agent to prevent Salmonellosis in swine.

Keywords: garlic essential oil, pig, salmonellosis, Salmonella enterica

Procedia PDF Downloads 174

Authors: Jun Hyung Lee, Robin B. Guevarra, Jin Ho Cho, Bo-Ra Kim, Jiwon Shin, Doo Wan Kim, Young Hwa Kim, Minho Song, Hyeun Bum Kim

Abstract:

Colibacillosis is one of the major health problems in young piglets ultimately resulting in their death, and it is common especially in young piglets. For the swine industry, colibacillosis is one of the important economic burdens. Therefore, it is necessary for the swine industries to prevent Colibacillosis in piglets in order to reduce economic losses. Thus, we tested three types of natural plant extracts (PEs) to evaluate antibacterial effects against Shiga toxin-producing Escherichia coli (STEC) isolated from the piglet. Three PEs including turmeric oleoresin (containing curcumin 79 to 85%), capsicum oleoresin (containing capsaicin 40%-40.1%), and garlic essential oil (100% natural garlic) were tested using the direct contact agar diffusion test, minimum inhibitory concentration test, growth curve assay, and heat stability test. The tests were conducted with PEs at each concentration of 2.5%, 5%, and 10%. For the heat stability test, PEs with 10% concentration were incubated at each 4, 20, 40, 60, 80, and 100 °C for 1 hour, then the direct contact agar diffusion test was used. For the positive and negative controls, 0.5N HCl and 1XPBS were used. All the experiments were duplicated. In the direct contact agar diffusion test, garlic essential oil with 2.5%, 5%, and 10% concentration showed inhibit zones of 1.1cm, 3.0cm, and 3.6 cm in diameters compared to that of 3.5cm diameter for 0.5N HCl. The minimum inhibited concentration of garlic essential oil was 2.5%. Growth curve assay showed that the garlic essential oil was able to inhibit STEC growth significantly after 4 hours. The garlic essential oil retained the ability to inhibit STEC growth after heat treatment at each temperature. However, turmeric and capsicum oleoresins were not able to significantly inhibit STEC growth by all the tests. Even though further tests using the piglets will be required to evaluate effects of garlic essential oil for the Colibacillosis prevention for piglets, our results showed that the garlic essential oil could be used as a potential natural agent to prevent Colibacillosis in swine.

Keywords: garlic essential oil, pig, Colibacillosis, Escherichia coli

Procedia PDF Downloads 260

Authors: Silvia Alaimo

Abstract:

This lecture brings to our attention the theme of spirituality within Gestalt therapy’s theoretical and clinical perspectives and which is closely connected to the fertile emptiness and creative indifference’ experiences. First of all, the premise that must be done is the overcoming traditional western culture’s philosophical and religious misunderstandings, such as the dicotomy between spirituality and pratical/material daily life, as well as the widespread secular perspective of classic psychology. Even fullness and emptiness have traditionally been associated with the concepts of being and not being. "There is only one way through which we can contact the deepest layers of our existence, rejuvenate our thinking and reach intuition (the harmony of thought and being): inner silence" (Perls) *. Therefore, "fertile void" doesn't mean empty in itself, but rather an useful condition of every creative and responsible act, making room for a deeper dimension close to spirituality. Spirituality concerns questions about the meaning of existence, which lays beyond the concrete and literal dimension, looking for the essence of things, and looking at the value of personal experience. Looking at fundamentals of Gestalt epistemology, phenomenology, aesthetics, and the relationship, we can reach the heart of a therapeutic work that takes spiritual contours and which are based on an embodied (incarnate size), through the relational aesthetic knowledge (Spagnuolo Lobb ), the deep contact with each other, the role of compassion and responsibility, as the patient's recognition criteria (Orange, 2013) rooted in the body. The aesthetic dimension, like the spiritual dimension to which it is often associated, is a subtle dimension: it is the dimension of the essence of things, of their "soul." In clinical practice, it implies that the relationship between therapist and patient is "in the absence of judgment," also called "zero point of creative indifference," expressed by ‘therapeutic mentality’. It consists in following with interest and authentic curiosity where the patient wants to go and support him in his intentionality of contact. It’s a condition of pure and simple awareness, of the full acceptance of "what is," a moment of detachment from one's own life in which one does not take oneself too seriously, a starting point for finding a center of balance and integration that brings to the creative act, to growth, and, as Perls would say, to the excitement and adventure of living.

Keywords: spirituality, bodily, embodied aesthetics, phenomenology, relationship

Procedia PDF Downloads 138

Authors: Chen Liu, Dawit Negussey

Abstract:

EPS (Expanded Polystyrene) geofoam as light-weight material in geotechnical applications are made of pre-expanded resin beads that form fused cellular micro-structures. The strength and deformation properties of geofoam blocks are determined by unconfined compression of small test samples between rigid loading plates. Applied loads are presumed to be supported uniformly over the entire mating end areas. Predictions of field performance on the basis of such laboratory tests widely over-estimate actual post-construction settlements and exaggerate predictions of long-term creep deformations. This investigation examined the development of contact pressures at a large number of discrete points at low and large strain levels for different densities of geofoam. Development of pressure patterns for fine and coarse interface material textures as well as for molding skin and hot wire cut geofoam surfaces were examined. The lab testing showed that I-Scan tactile sensors are useful for detailed observation of contact pressures at a large number of discrete points simultaneously. At low strain level (1%), the lower density EPS block presents low variations in localized stress distribution compared to higher density EPS. At high strain level (10%), the dense geofoam reached the sensor cut-off limit. The imprint and pressure patterns for different interface textures can be distinguished with tactile sensing. The pressure sensing system can be used in many fields with real-time pressure detection. The research findings provide a better understanding of EPS geofoam behavior for improvement of design methods and performance prediction of critical infrastructures, which will be anticipated to guide future improvements in design and rapid construction of critical transportation infrastructures with geofoam in geotechnical applications.

Keywords: geofoam, pressure distribution, tactile pressure sensors, interface

Procedia PDF Downloads 174

Authors: Ioan Rusu

Abstract:

In the operation of power transformers of 110 kV/MV from substations, these are traveled by fault current resulting from MV line damage. Defect electrical contacts are heated when they are travelled from fault currents. In the case of high temperatures when 135 °C is reached, the electrical insulating oil in the vicinity of the electrical faults comes into contact with these contacts releases gases, and activates the electrical protection. To avoid auto-flammability of electro-insulating oil, we designed a security system thermal of electrical contact defects by pouring fire-resistant polyurethane foam, mastic or mortar fire inside a cardboard electro-insulating cylinder. From practical experience, in the exploitation of power transformers of 110 kV/MT in oil electro-insulating were recorded some passing disconnecting commanded by the gas protection at internal defects. In normal operation and in the optimal load, nominal currents do not require thermal secure contacts inside electrical transformers, contacts are made at the fabrication according to the projects or to repair by solder. In the case of external short circuits close to the substation, the contacts inside electrical transformers, even if they are well made in sizes of Rcontact = 10^‑6 Ω, are subjected to short-circuit currents of the order of 10 kA-20 kA which lead to the dissipation of some significant second-order electric powers, 100 W-400 W, on contact. At some internal or external factors which action on electrical contacts, including electrodynamic efforts at short-circuits, these factors could be degraded over time to values in the range of 10^-4 Ω to 10^-5 Ω and if the action time of protection is great, on the order of seconds, power dissipation on electrical contacts achieve high values of 1,0 kW to 40,0 kW. This power leads to strong local heating, hundreds of degrees Celsius and can initiate self-ignition and burning oil in the vicinity of electro-insulating contacts with action the gas relay. Degradation of electrical contacts inside power transformers may not be limited for the duration of their operation. In order to avoid oil burn with gas release near electrical contacts, at short-circuit currents 10 kA-20 kA, we have outlined the following solutions: covering electrical contacts in fireproof materials that would avoid direct burn oil at short circuit and transmission of heat from electrical contact along the conductors with heat dissipation gradually over time, in a large volume of cooling. Flame retardant materials are: polyurethane foam, mastic, cement (concrete). In the normal condition of operation of transformer, insulating of conductors coils is with paper and insulating oil. Ignition points of its two components respectively are approximated: 135 °C heat for oil and 200 ⁰C for paper. In the case of a faulty electrical contact, about 10^-3 Ω, at short-circuit; the temperature can reach for a short time, a value of 300 °C-400 °C, which ignite the paper and also the oil. By burning oil, there are local gases that disconnect the power transformer. Securing thermal electrical contacts inside the transformer, in cardboard tube with polyurethane foams, mastik or cement, ensures avoiding gas release and also gas protection working.

Keywords: power transformer, oil insulatation, electric contacts, Bucholtz relay

Procedia PDF Downloads 158

Authors: A. L. R. Rangel, J. A. M. Chaves, A. P. R. Alves Claro

Abstract:

Surface modification of titanium and its alloys using TiO2 nanotube growth has been widely studied for biomedical field due to excellent interaction between implant and biological environment. The success of this treatment is directly related to anatase phase formation (TiO2 phase) which affects the cells growth. The aim of this study was to evaluate the phases formed in the nanotubes growth on the Ti-15Mo surface. Nanotubes were grown by electrochemical anodization of the alloy in ammonium fluoride based glycerol electrolyte for 24 hours at 20V. Then, the samples were annealed at 200°,400°, 450°, 500°, 600°, and 800° C for 1 hour. Contact angles measurements, scanning electron microscopy images and X rays diffraction analysis (XRD) were carried out for all samples. Raman Spectroscopy was used to evaluate TiO2 phases transformation in nanotubes samples as well. The results of XRD showed anatase formation for lower temperatures, while at 800 ° C the rutile phase was observed all over the surface. Raman spectra indicate that this phase transition occurs between 500 and 600 °C. The different phases formed have influenced the nanotubes morphologies, since higher annealing temperatures induced agglutination of the TiO2 layer, disrupting the tubular structure. On the other hand, the nanotubes drastically reduced the contact angle, regardless the annealing temperature.

Keywords: nanotubes, TiO2, titanium alloys, Ti-15Mo

Procedia PDF Downloads 384

Authors: M. Bouhoun Ali, A. Y. Badjah Hadj Ahmed, M. Attou, A. Elias, M. A. Didi

Abstract:

The extraction of uranium(VI) from aqueous solutions has been investigated using 1-hydroxyhexadecylidene-1,1-diphosphonic acid (HHDPA) and 1-hydroxydodecylidene-1,1-diphosphonic acid (HDDPA), which were synthesized and characterized by elemental analysis and by FT-IR, 1H NMR, 31P NMR spectroscopy. In this paper, we propose a tentative assignment for the shifts of those two ligands and their specific complexes with uranium(VI). We carried out the extraction of uranium(VI) by HHDPA and HDDPA from [carbon tetrachloride + 2-octanol (v/v: 90%/10%)] solutions. Various factors such as contact time, pH, organic/aqueous phase ratio and extractant concentration were considered. The optimum conditions obtained were: contact time= 20 min, organic/aqueous phase ratio = 1, pH value = 3.0 and extractant concentration = 0.3M. The extraction yields are more significant in the case of the HHDPA which is equipped with a hydrocarbon chain, longer than that of the HDDPA. Logarithmic plots of the uranium(VI) distribution ratio vs. pHeq and the extractant concentration showed that the ratio of extractant to extracted uranium(VI) (ligand/metal) is 2:1. The formula of the complex of uranium(VI) with the HHDPA and the DHDPA is UO2(H3L)2 (HHDPA and DHDPA are denoted as H4L). A spectroscopic analysis has showed that coordination of uranium(VI) takes place via oxygen atoms.

Keywords: liquid-liquid extraction, uranium(vi), 1-hydroxyalkylidene-1, 1-diphosphonic acids, hhdpa, hddpa, aqueous solution

Procedia PDF Downloads 269

Authors: María José Benitez Jimenez

Abstract:

This research is based on the hypothesis that, despite being found that the problem of violence against the female partner occurs in all social classes, the criminal intervention falls, above all, on victims and aggressors with sociodemographic characteristics of the most excluded social groups. The methodology used in this study has been a collection of information through Spanish official statistics from 2004 to 2016: population, police, judicial and penitentiary data from Ministry of Interior, Ministry of Justice and statistics National Institute. The data provided show that women victims and aggressors who come into contact with criminal intervention bodies for filing a complaint or having been reported, respectively, show a very high percentage, usually well above 50%, only primary studies or even that. Their employment situation is also precarious, in a percentage that could also be around 70%. The percentage distribution of these two variables is clearly above that which occurs in the whole of the Spanish population, in a particularly marked way as regards the employment situation. Immigrants triple, as victims or as aggressors of gender violence, the percentages of the Spanish population in terms of their contact with the organs of criminal intervention. Also the rate of foreign inmates in prisons for violence against the female couple doubles that of Spanish inmates.

Keywords: inmigrants, intimate partner violence, Spain, sociodemographic characteristics

Procedia PDF Downloads 201

Authors: Jatziri Y. Moreno-Martinez, Arturo Galvan, Xavier Chavez Cardenas, Hiram Arroyo

Abstract:

Several methods have been utilized to study the prediction of cracking of concrete structural under loading. The finite element analysis is an alternative that shows good results. The aim of this work was the numerical study of the width crack in reinforced concrete beams with dapped ends, these are frequently found in bridge girders and precast concrete construction. Properly restricting cracking is an important aspect of the design in dapped ends, it has been observed that the cracks that exceed the allowable widths are unacceptable in an aggressive environment for reinforcing steel. For simulating the crack width, the discrete crack approach was considered by means of a Cohesive Zone (CZM) Model using a function to represent the crack opening. Two cases of dapped-end were constructed and tested in the laboratory of Structures and Materials of Engineering Institute of UNAM. The first case considers a reinforcement based on hangers as well as on vertical and horizontal ring, the second case considers 50% of the vertical stirrups in the dapped end to the main part of the beam were replaced by an equivalent area (vertically projected) of diagonal bars under. The loading protocol consisted on applying symmetrical loading to reach the service load. The models were performed using the software package ANSYS v. 16.2. The concrete structure was modeled using three-dimensional solid elements SOLID65 capable of cracking in tension and crushing in compression. Drucker-Prager yield surface was used to include the plastic deformations. The reinforcement was introduced with smeared approach. Interface delamination was modeled by traditional fracture mechanics methods such as the nodal release technique adopting softening relationships between tractions and the separations, which in turn introduce a critical fracture energy that is also the energy required to break apart the interface surfaces. This technique is called CZM. The interface surfaces of the materials are represented by a contact elements Surface-to-Surface (CONTA173) with bonded (initial contact). The Mode I dominated bilinear CZM model assumes that the separation of the material interface is dominated by the displacement jump normal to the interface. Furthermore, the opening crack was taken into consideration according to the maximum normal contact stress, the contact gap at the completion of debonding, and the maximum equivalent tangential contact stress. The contact elements were placed in the crack re-entrant corner. To validate the proposed approach, the results obtained with the previous procedure are compared with experimental test. A good correlation between the experimental and numerical Load-Displacement curves was presented, the numerical models also allowed to obtain the load-crack width curves. In these two cases, the proposed model confirms the capability of predicting the maximum crack width, with an error of ± 30 %. Finally, the orientation of the crack is a fundamental for the prediction of crack width. The results regarding the crack width can be considered as good from the practical point view. Load-Displacement curve of the test and the location of the crack were able to obtain favorable results.

Keywords: cohesive zone model, dapped-end beams, discrete crack approach, finite element analysis

Procedia PDF Downloads 167

Authors: Nasser A. M. Barakat

Abstract:

Membrane technology is the most promising process for oil-water separation operation if the hydrophilicity, fouling and reusability properties could be improved. In this study, novel effective and reusable membrane for oil-water separation process is introduced based on modification of polysulfone (PSF) electrospun nanofiber mats. The modification process was achieved by incorporation of NaOH nanoparticles inside the PSF nanofibers, and formation of a thin layer from a polyamide polymer on the surface of the electrospun mat. Typically, solutions composed of PSF and NaOH (twelve solutions were prepared based on different PSF concentrations; 15, 18 and 20 wt%, and various NaOH content; 1.5, 1.7 and 2.5 wt%) have been electrospun, then the dried nanofiber mats were treated by m-phenylenediamine and 1,3,5-benzenetricarbonyl chloride to form polyamide thin layer on the surface of the mats. The results indicated that incorporation of NaOH and the formed polyamide could decrease the water contact angle from ~ 130˚ to 13˚ for the nanofiber mats obtained from 20 wt% PSF solutions containing 1.7 wt% sodium hydroxide powders. Interestingly, the membrane having the lowest contact angle could separate oil-water mixture for three successive cycles and 100% removal of the oil with relatively high water flux; 5.5 m3/m2.day. Overall, simplicity of the manufacturing technique, and effectiveness and reusability of the produced nanofiber mats open new avenue for the introduced as promising membranes for the oil-water separation process.

Keywords: electrospinning, oil-water separation, hydrophilic membrane, nanofibers

Procedia PDF Downloads 341

Authors: Vineel Inampudi, Arjun Prakash, Joseph Vinod

Abstract:

Aims and Objectives: To evaluate the interrater reliability in grading ASPECTS score, between emergency medicine physician at first contact and radiologist among patients with acute ischemic stroke. Materials and Methods: We conducted a retrospective analysis of 86 acute ischemic stroke cases referred to the Department of Radiodiagnosis during November 2014 to January 2016. The imaging (plain CT scan) was performed using GE Bright Speed Elite 16 Slice CT Scanner. ASPECTS score was calculated separately by an emergency medicine physician and radiologist. Interrater reliability for total and dichotomized ASPECTS (≥ 6 and < 6) scores were assessed using statistical analysis (ICC and Cohen ĸ coefficients) on SPSS software (v17.0). Results: Interrater agreement for total and dichotomized ASPECTS was substantial (ICC 0.79 and Cohen ĸ 0.68) between the emergency physician and radiologist. Mean difference in ASPECTS between the two readers was only 0.15 with standard deviation of 1.58. No proportionality bias was detected. Bland Altman plot was constructed to demonstrate the distribution of ASPECT differences between the two readers. Conclusion: Substantial interrater agreement was noted in grading ASPECTS between emergency medicine physician at first contact and radiologist thereby confirming its robustness even in a rural setting.

Keywords: ASPECTS, computed tomography, MCA territory, stroke

Procedia PDF Downloads 236

Authors: S. V. Ukwungwu, A. J. Abbas, G. G. Nasr

Abstract:

The increasing high price of natural gas and oil with attendant increase in energy demand on world markets in recent years has stimulated interest in recovering residual oil saturation across the globe. In order to meet the energy security, efforts have been made in developing new technologies of enhancing the recovery of oil and gas, utilizing techniques like CO2 flooding, water injection, hydraulic fracturing, surfactant flooding etc. Surfactant flooding however optimizes production but poses risk to the environment due to their toxic nature. Amongst proven records that have utilized other type of bacterial in producing biosurfactants for enhancing oil recovery, this research uses a technique to combine biosurfactants that will achieve a scale of EOR through lowering interfacial tension/contact angle. In this study, three biosurfactants were produced from three Bacillus species from freeze dried cultures using sucrose 3 % (w/v) as their carbon source. Two of these produced biosurfactants were screened with the TEMCO Pendant Drop Image Analysis for reduction in IFT and contact angle. Interfacial tension was greatly reduced from 56.95 mN.m-1 to 1.41 mN.m-1 when biosurfactants in cell-free culture (Bacillus licheniformis) were used compared to 4. 83mN.m-1 cell-free culture of Bacillus subtilis. As a result, cell-free culture of (Bacillus licheniformis) changes the wettability of the biosurfactant treatment for contact angle measurement to more water-wet as the angle decreased from 130.75o to 65.17o. The influence of microbial treatment on crushed rock samples was also observed by qualitative wettability experiments. Treated samples with biosurfactants remained in the aqueous phase, indicating a water-wet system. These results could prove that biosurfactants can effectively change the chemistry of the wetting conditions against diverse surfaces, providing a desirable condition for efficient oil transport in this way serving as a mechanism for EOR. The environmental friendly effect of biosurfactants applications for industrial purposes play important advantages over chemically synthesized surfactants, with various possible structures, low toxicity, eco-friendly and biodegradability.

Keywords: bacillus, biosurfactant, enhanced oil recovery, residual oil, wettability

Procedia PDF Downloads 279