Search results for: degree and size
7689 Rapid Biosynthesis of Silver Nanoparticles Using Trachyspermum Ammi
Authors: Rajesh Kumar Meena, Suman Jhajharia, Goutam Chakraborty
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Plasmonic silver nanoparticles (Ag NPs) was synthesized by chemical reduction method using Trachyspermum Ammi (TA, Ajwain) seeds extract in aqueous medium and AgNO3 solution at different time interval. Reaction time, and concentration of AgNO3 and TA could accelerate the reduction rate of Ag+ and affect AgNPs size and concentration of NPs. Surface plasmon resonance band centered at 420-430 nm (88.78nm) was recognised as first exitonic peak of UV-Vis absorption spectra of AgNPs that used to calculate the particle size (10-30 nm). FTIR results TA supported AgNPs showed decrease in intensity of peaks at 3394, 1716 and 1618 cm-1 with respect to the plain TA indicating the involvement of O-H, carbonyl group and C=C stretching in formation of TA-AgNPs aggregates. The C-O-C and C-N stretching suggested the presence of many phytochemicals on the surface of the NPs. Impedance study reveals that at low concentration of TA the rate of charge transfer is in TA-AgNPs aggregates, found higher than the higher TA concentration condition that confirms the stability of AgNPs in water. Extract reduce silver ions into silver nanoparticles (NPs) of size 6-50nm. Pronounce effect of the time on Ag NPs concentration and particle size, was exhibited by the system These biogenic Ag NPs are characterized using UV- Vis spectrophotometry (UV-Visible), Fourier transformation infrared (FTIR) and XRD. These studies give us inside view of the most probable mechanism of biosynthesis and optoelectronic properties of the as synthesised Ag NPs.Keywords: antimicrobial activity, bioreduction, capping agent, silver nanoparticles
Procedia PDF Downloads 3187688 Effect of Molybdenum Addition to Aluminum Grain Refined by Titanium Plus Boron on Its Grain Size and Mechanical Characteristics in the Cast and After Pressing by the Equal Channel Angular Pressing Conditions
Authors: A. I. O. Zaid, A. M. Attieh, S. M. A. Al Qawabah
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Aluminum and its alloys solidify in columnar structure with large grain size which tends to reduce their mechanical strength and surface quality. They are, therefore, grain refined by addition of either titanium or titanium plus boron to their melt before solidification. Equal channel angular pressing, ECAP, process is a recent forming method for producing heavy plastic deformation in materials. In this paper, the effect of molybdenum addition to aluminum grain refined by Ti+B on its metallurgical and mechanical characteristics are investigated in the as cast condition and after pressing by the ECAP process. It was found that addition of Mo or Ti+B alone or together to aluminum resulted in grain refining of its microstructure in the as cast condition, as the average grain size was reduced from 139 micron to 46 micron when Mo and Ti+B are added together. Pressing by the ECAP process resulted in further refinement of the microstructure where 32 micron of average grain size was achieved in Al and the Al-Mo microalloy. Regarding the mechanical strength, addition of Mo or Ti+B alone to Al resulted in deterioration of its mechanical behavior but resulted in enhancement of its mechanical behavior when added together, increase of 10% in flow stress was achieved at 20% strain. However, pressing by ECAP addition of Mo or Ti+B alone to Al resulted in enhancement of its mechanical strength but reduced its strength when added together.Keywords: ECAP, aluminum, cast, mechanical characteristics, Mo grain refiner
Procedia PDF Downloads 4667687 Synthesis and Characterization of Novel Hollow Silica Particle through DODAB Vesicle Templating
Authors: Eun Ju Park, Wendy Rusli, He Tao, Alexander M. Van Herk, Sanggu Kim
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Hollow micro-/nano- structured materials have proven to be promising in wide range of applications, such as catalysis, drug delivery and controlled release, biotechnology, and personal and consumer care. Hollow sphere structures can be obtained through various templating approaches; colloid templates, emulsion templates, multi-surfactant templates, and single crystal templates. Vesicles are generally the self-directed assemblies of amphiphilic molecules including cationic, anionic, and cationic surfactants in aqueous solutions. The directed silica capsule formations were performed at the surface of dioctadecyldimethylammoniumbromide(DODAB) bilayer vesicles as soft template. The size of DODAB bilayer vesicles could be tuned by extrusion of a preheated dispersion of DODAB. The synthesized hollow silica particles were characterized by conventional TEM, cryo-TEM and SEM to determine the morphology and structure of particles and dynamic light scattering (DLS) method to measure the particle size and particle size distribution.Keywords: characterization, DODAB, hollow silica particle, synthesis, vesicle
Procedia PDF Downloads 3047686 Effect of Si/Al Ratio on SSZ-13 Crystallization and Its Methanol-To-Olefins Catalytic Properties
Authors: Zhiqiang Xu, Hongfang Ma, Haitao Zhang, Weixin Qian, Weiyong Ying
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SSZ-13 materials with different Si/Al ratio were prepared by varying the composition of aluminosilicate precursor solutions upon hydrothermal treatment at 150 °C. The Si/Al ratio of the initial system was systematically changed from 12.5 to infinity in order to study the limits of Al composition in precursor solutions for constructing CHA structure. The intermediates and final products were investigated by complementary techniques such as XRD, HRTEM, FESEM, and chemical analysis. NH3-TPD was used to study the Brønsted acidity of SSZ-13 samples with different Si/Al ratios. The effect of the Si/Al ratio on the precursor species, ultimate crystal size, morphology and yield was investigated. The results revealed that Al species determine the nucleation rate and the number of nuclei, which is tied to the morphology and yield of SSZ-13. The size of SSZ-13 increased and the yield decreased as the Si/Al ratio was improved. Varying Si/Al ratio of the initial system is a facile, commercially viable method of tailoring SSZ-13 crystal size and morphology. Furthermore, SSZ-13 materials with different Si/Al ratio were tested as catalysts for the methanol to olefins (MTO) reaction at 350 °C. SSZ-13 with the Si/Al ratio of 35 shows the best MTO catalytic performance.Keywords: crystallization, MTO, Si/Al ratio, SSZ-13
Procedia PDF Downloads 2897685 Structural and Magnetic Properties of Cr Doped Ni-Zn Nanoferrites Prepared by Co-Precipitation Method
Authors: E. Ateia, L. M. Salah, A. H. El-Bassuony
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Physical properties of nanocrystalline Ni1-xZnxCryFe2-yO4, (x=0.3, 0.5 and y=0.0, 0.1) with estimated crystallite size of 16.4 nm have been studied. XRD pattern of all prepared systems shows that, the nanosamples without Cr3+ have a cubic spinel structure with the appearance of small peaks designated as a secondary phase. Magnetic constants such as saturation magnetization, (MS) remanent magnetization (Mr) and coercive field (Hc) were obtained and reported. The obtained data shows that, the addition of Cr3+ (0.1mol) decreases the saturation magnetization. This is due to the decrease of magnetic moment of Cr3+ ion (3.0 μB) with respect to Fe3+ ion (5.85 μB). The electrical properties of the investigated samples were also investigated.Keywords: electrical conductivity, ferrites, grain size, sintering
Procedia PDF Downloads 2827684 The Educational Philosophies and Teaching Style Preferences of College Faculty at Selected Universities in the South of Metro Manila
Authors: Grace D. Severo, Lopita U. Jung
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This study aimed to determine the educational philosophies and teaching styles of the college faculty of the University of Perpetual Help System DALTA in the campuses of Las-Piñas, Molino, and Calamba, south of Metro Manila. It sought to determine the relationships of educational philosophy and teaching styles of the college faculty vis-à-vis the university system’s educational philosophies and teaching style preferences. A hundred and five faculty members from the Colleges of Education, Arts and Sciences responded to the survey during the academic year 2014-2015. The Philosophy of Adult Education Inventory measured the faculty’s preferred educational philosophies. The Principles of Adult Learning Scale measured the faculty’s teaching style preference. Findings show that there is a similarity between the university system and the faculty members in using the progressive educational philosophy, however both contrasted in the preferred teaching style. Majority of the faculty held progressive educational philosophy but their preference for teacher-centered teaching style did not match. This implies that the majority are certain of having progressive educational philosophy but are not utilizing the learner-centered teaching styles; a high degree of support and commitment to practice a progressive and humanist philosophical orientation in education; and a high degree of support on teacher-centered teaching style promotion from the institution can strengthen a high degree of commitment for the faculty to enunciate their values and practice through these educational philosophies and teaching styles.Keywords: educational philosophies, teaching styles, philosophy of adult education inventory, principles of adult learning scale
Procedia PDF Downloads 3597683 Characterization of Nanoemulsion Incorporating Crude Cocoa Polyphenol
Authors: Suzannah Sharif, Aznie Aida Ahmad, Maznah Ismail
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Cocoa bean is the raw material for products such as cocoa powder and chocolate. Cocoa bean contains polyphenol which has been shown in several clinical studies to confer beneficial health effects. However studies showed that cocoa polyphenol absorption in the human intestinal tracts are very low. Therefore nanoemulsion may be one way to increase the bioavailability of cocoa polyphenol. This study aim to characterize nanoemulsion incorporating crude cocoa polyphenol produced using high energy technique. Cocoa polyphenol was extracted from fresh freeze-dried cocoa beans from Malaysia. The particle distribution, particle size, and zeta potential were determined. The emulsion was also analysed using transmission electron microscope to visualize the particles. Solubilization study was conducted by titrating the nanoemulsion into distilled water or 1% surfactant solution. Result showed that the nanoemulsion contains particle which have narrow size distribution. The particles size average at 112nm with zeta potential of -45mV. The nanoemulsions behave differently in distilled water and surfactant solution.Keywords: cocoa, nanoemulsion, cocoa polyphenol, solubilisation study
Procedia PDF Downloads 4607682 The Obstacles of Applying Electronic Administration at the University of Tabuk from Its Academic Leaders' Perspectives
Authors: Saud Eid Alanazi
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The study aimed at recognizing the obstacles of applying of Electronic Administration (e-administration), which refers to any of a number of mechanisms which convert what in a traditional office are paper processes into electronic processes, with the goal being to create a paperless office and improve productivity and performance at the University of Tabuk from its Academic Leaders' Perspectives. The sample of the study consisted of (98) members from deans, vice deans and head of departments from different specialization, gender and position. For achieving the aim of the study, a questionnaire was developed including (45) items distributed into three domains (administrative, human and technical obstacles) . By using appropriate statistical methods to analyze the information, the results indicated that the administrative obstacles domain came in the first rank with a high degree, and the human and technical obstacles came at the second rank with a moderate degree. The study also showed that there were no statistically significant differences attributed to the variables of the members (specialization, gender and position).Keywords: administration, electronic administration, obstacles, technology, universities
Procedia PDF Downloads 3787681 Prediction of Endotracheal Tube Size in Children by Predicting Subglottic Diameter Using Ultrasonographic Measurement versus Traditional Formulas
Authors: Parul Jindal, Shubhi Singh, Priya Ramakrishnan, Shailender Raghuvanshi
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Background: Knowledge of the influence of the age of the child on laryngeal dimensions is essential for all practitioners who are dealing with paediatric airway. Choosing the correct endotracheal tube (ETT) size is a crucial step in pediatric patients because a large-sized tube may cause complications like post-extubation stridor and subglottic stenosis. On the other hand with a smaller tube, there will be increased gas flow resistance, aspiration risk, poor ventilation, inaccurate monitoring of end-tidal gases and reintubation may also be required with a different size of the tracheal tube. Recent advancement in ultrasonography (USG) techniques should now allow for accurate and descriptive evaluation of pediatric airway. Aims and objectives: This study was planned to determine the accuracy of Ultrasonography (USG) to assess the appropriate ETT size and compare it with physical indices based formulae. Methods: After obtaining approval from Institute’s Ethical and Research committee, and parental written and informed consent, the study was conducted on 100 subjects of either sex between 12-60 months of age, undergoing various elective surgeries under general anesthesia requiring endotracheal intubation. The same experienced radiologist performed ultrasonography. The transverse diameter was measured at the level of cricoids cartilage by USG. After USG, general anesthesia was administered using standard techniques followed by the institute. An experienced anesthesiologist performed the endotracheal intubations with uncuffed endotracheal tube (Portex Tracheal Tube Smiths Medical India Pvt. Ltd.) with Murphy’s eye. He was unaware of the finding of the ultrasonography. The tracheal tube was considered best fit if air leak was satisfactory at 15-20 cm H₂O of airway pressure. The obtained values were compared with the values of endotracheal tube size calculated by ultrasonography, various age, height, weight-based formulas and diameter of right and left little finger. The correlation of the size of the endotracheal tube by different modalities was done and Pearson's correlation coefficient was obtained. The comparison of the mean size of the endotracheal tube by ultrasonography and by traditional formula was done by the Friedman’s test and Wilcoxon sign-rank test. Results: The predicted tube size was equal to best fit and best determined by ultrasonography (100%) followed by comparison to left little finger (98%) and right little finger (97%) and age-based formula (95%) followed by multivariate formula (83%) and body length (81%) formula. According to Pearson`s correlation, there was a moderate correlation of best fit endotracheal tube with endotracheal tube size by age-based formula (r=0.743), body length based formula (r=0.683), right little finger based formula (r=0.587), left little finger based formula (r=0.587) and multivariate formula (r=0.741). There was a strong correlation with ultrasonography (r=0.943). Ultrasonography was the most sensitive (100%) method of prediction followed by comparison to left (98%) and right (97%) little finger and age-based formula (95%), the multivariate formula had an even lesser sensitivity (83%) whereas body length based formula was least sensitive with a sensitivity of 78%. Conclusion: USG is a reliable method of estimation of subglottic diameter and for prediction of ETT size in children.Keywords: endotracheal intubation, pediatric airway, subglottic diameter, traditional formulas, ultrasonography
Procedia PDF Downloads 2357680 Effect of Co-doping on Polycrystalline Ni-Mn-Ga
Authors: Mahsa Namvari, Kari Ullakko
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It is well-known that the Co-doping of ferromagnetic shape memory alloys (FSMAs) is a crucial tool to control their multifunctional properties. The present work investigates the use of small quantities of Co to fine-tune the transformation, structure, microstructure, mechanical and magnetic properties of the polycrystalline Ni₄₉.₈Mn₂₈.₅Ga₂₁.₇ (at.%) alloy, At Co concentrations of 1-1.5 at.%, a microstructure with an average grain size of about 2.00 mm was formed with a twin structure, enabling the experimental observation of magnetic-field-induced twin variant rearrangement. At higher levels of Co-doping, the grain size was essentially reduced, and the crystal structure of the martensitic phase became 2M martensite. The decreasing grain size and changing crystal structure are attributed to the progress of γ-phase precipitates. Alongside the academic aspect, the results of the present work point to the commercial advantage of fabricating 10M Co-doped Ni-Mn-Ga actuating elements made from large grains of polycrystalline ingots obtained by a standard melting facility instead of grown single crystals.Keywords: Ni-Mn-Ga, ferromagnetic shape memory, martensitic phase transformation, grain growth
Procedia PDF Downloads 797679 Technology Use by African Smallholder Farmers and the Significant Mediating Factors
Authors: Enobong Akpan-Etuk
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The willingness of smallholder farmers in Africa to adopt new agricultural technologies has been low, despite the technological advancement in agriculture. Although technology is seen as the main route out of the traditional methods of food production and poverty, the rate of adoption of agricultural technology remains low among farmers in Africa. Factors affecting the adoption of agricultural technologies include the acquisition of information, characteristics of the technology, education of farmers, social capital, farm size, and household size. This paper explored the literature on the influence of the factors that determine the adoption of technology by smallholder farmers.Keywords: smallholder, technology, adoption
Procedia PDF Downloads 1367678 Breeding Biology of Priacanthus hamrur (Forsskal) off Mangalore Coast, Karnataka, India
Authors: H. N. Anjanayappa, S. Benakappa, A. T. Ramachandra Naik, P. Nayana, D. P. Rajesh
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Fishes of the family Priacanthidae, popularly called big eye or bulls eye. Priacanthus hamrur is an important deep-water inhabitant of great commercial value. High percentage of landings of Priancanthids used as raw material for surimi, sausage and other fishery by-products. Presently, it has great demand in Singapore Thailand, Taiwan, Hong Kong and other countries. For the maturation studies, samples were collected from commercial landing centre, Mangalore. Studies on reproductive biology showed that Priacanthus hamrur spawns twice in a year, the spawning season extending from March to May and October to November. Based on the percentage occurrence of mature fishes in various size group it was inferred that male attained maturity at smaller size than female. This study will enable us to understand the spawning periodicity, cyclic morphological changes in male, female gonads and also it helps to improve stock size by enforcing fishing ban in particular season by assessing spawning periodicity.Keywords: breeding biology, Mangalore, morphological changes, Priacanthus hamrur
Procedia PDF Downloads 2877677 Synthesis of PVA/γ-Fe2O3 Used in Cancer Treatment by Hyperthermia
Authors: Sajjad Seifi Mofarah, S. K. Sadrnezhaad, Shokooh Moghadam, Javad Tavakoli
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In recent years a new method of combination treatment for cancer has been developed and studied that has led to significant advancements in the field of cancer therapy. Hyperthermia is a traditional therapy that, along with a creation of a medically approved level of heat with the help of an alternating magnetic AC current, results in the destruction of cancer cells by heat. This paper gives details regarding the production of the spherical nanocomposite PVA/γ-Fe2O3 in order to be used for medical purposes such as tumor treatment by hyperthermia. To reach a suitable and evenly distributed temperature, the nanocomposite with core-shell morphology and spherical form within a 100 to 200 nanometer size was created using phase separation emulsion, in which the magnetic nano-particles γ-Fe2O3 with an average particle size of 20 nano-meters and with different percentages of 0.2, 0.4, 0.5, and 0.6 were covered by polyvinyl alcohol. The main concern in hyperthermia and heat treatment is achieving desirable specific absorption rate (SAR) and one of the most critical factors in SAR is particle size. In this project all attempts has been done to reach minimal size and consequently maximum SAR. The morphological analysis of the spherical structure of the nanocomposite PVA/γ-Fe2O3 was achieved by SEM analyses and the study of the chemical bonds created was made possible by FTIR analysis. To investigate the manner of magnetic nanocomposite particle size distribution a DLS experiment was conducted. Moreover, to determine the magnetic behavior of the γ-Fe2O3 particle and the nanocomposite PVA/γ-Fe2O3 in different concentrations a VSM test was conducted. To sum up, creating magnetic nanocomposites with a spherical morphology that would be employed for drug loading opens doors to new approaches in developing nanocomposites that provide efficient heat and a controlled release of drug simultaneously inside the magnetic field, which are among their positive characteristics that could significantly improve the recovery process in patients.Keywords: nanocomposite, hyperthermia, cancer therapy, drug releasing
Procedia PDF Downloads 2937676 Association of Leptin Gene T3469C Polymorphism on Reproductive Performance of Purebred Sows
Authors: Mariedel Autriz, Angel Lambio, Renato Vega, Severino Capitan, Rita Laude
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The study was conducted to associate genetic polymorphism of the leptin gene T3469C with reproductive performance in purebred sows. DNA were isolated from hair follicles of 29 Landrace and 24 Large White sows. Amplification of the leptin gene was done followed by Hinf1digestion to determine the base at the T3469C site. Electrophoresis of the digestion products revealed that there were 25 Landrace and 15 Large White sows with the TT genotype while there were 3 Landrace and 6 Large White TC. There was 1 CC for Landrace and 3 for Large White. Significant genotype associations were observed for total litter size born and total born alive. Significant breed differences, on the other hand, was observed for gestation length and average birth weight. Significant breed by genotype interaction was observed in litter size total born and litter size born alive.Keywords: genetic polymorphism, leptin, swine, T3469C
Procedia PDF Downloads 4167675 Characterization of Edible Film from Uwi Starch (Dioscorea alata L.)
Authors: Miksusanti, Herlina, Wiwin
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The research about modification uwi starch (Dioscorea alata L) by using propylene oxide has been done. Concentration of propylene oxide were 6%(v/w), 8%(v/w), and 10%(v/w). The amilograf parameters after modification were characteristic breakdown viscosity 43 BU and setback viscosity 975 BU. The modification starch have edible properties according to FDA (Food and Drug Administration) which have degree of modification < 7%, degree of substitution < 0,1 and propylene oxide concentration < 10%(v/w). The best propylene oxide in making of edible film was 8 %( v/w). The starch control can be made into edible film with thickness 0,136 mm, tensile strength 20,4605 MPa and elongation 22%. Modification starch of uwi can be made into edible film with thickness 0,146 mm, tensile strength 25, 3521 Mpa, elongation 30% and water vapor transmission 7, 2651 g/m2/24 hours. FTIR characterization of uwi starch showed the occurrence of hydroxypropylation. The peak spectrum at 2900 cm-1 showed bonding of C-H from methyl group, which is characteristic for modification starch with hydroxypropyl. Characterization with scanning electron microscopy showed that modification of uwi starch has turned the granule of starch to be fully swallon.Keywords: uwi starch, edible film, propylen oxide, modification
Procedia PDF Downloads 2907674 Cultural Aspects of Tax Compliance of Medium Size Enterprises in South Africa
Authors: Oludele A. Akinboade
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The paper discusses cultural aspects of tax compliance of medium size companies (MEs) in South Africa to enhance tax compliance. A survey of 641 companies in eight provinces was made. Racial identities of ME owners are not significant in explaining differences in tax registration compliance. Black ownership of MEs is negatively and highly significantly correlated with pay as you earn compliance. The opposite is found in favour of Asian ME owners. White ownership of MEs is negative and weakly (10%) significantly correlated with company income tax compliance while the opposite is found in favour of Asian ownership. Race is negative and highly significant in explaining White owned MEs value added tax compliance behaviour. The opposite is found in favour of Asian ME owners. Black ownership of MEs is negatively and weakly significantly(10%) associated with timely submission of tax returns.Keywords: tax compliance, cultural diversity, medium size companies, South Africa
Procedia PDF Downloads 3007673 Business Program Curriculum with Industry-Recognized Certifications: An Empirical Study of Exam Results and Program Curriculum
Authors: Thomas J. Bell III
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Pursuing a business degree is fraught with perplexing questions regarding the rising tuition cost and the immediate value of earning a degree. Any decision to pursue an undergraduate business degree is perceived to have value if it facilitates post-graduate job placement. Business programs have decreased value in the absence of innovation in business programs that close the skills gap between recent graduates and employment opportunities. Industry-based certifications are seemingly becoming a requirement differentiator among job applicants. Texas Wesleyan University offers a Computer Information System (CIS) program with an innovative curriculum that integrates industry-recognized certification training into its traditional curriculum with core subjects and electives. This paper explores a culture of innovation in the CIS business program curriculum that creates sustainable stakeholder value for students, employers, the community, and the university. A quantitative research methodology surveying over one-hundred students in the CIS program will be used to examine factors influencing the success or failure of students taking certification exams. Researchers will analyze control variables to identify specific correlations between practice exams, teaching pedagogy, study time, age, work experience, etc. This study compared various exam preparation techniques to corresponding exam results across several industry certification exams. The findings will aid in understanding control variables with correlations that positively and negatively impact exam results. Such discovery may provide useful insight into pedagogical impact indicators that positively contribute to certification exam success and curriculum enhancement.Keywords: taking certification exams, exam training, testing skills, exam study aids, certification exam curriculum
Procedia PDF Downloads 777672 Implementing Two Rotatable Circular Polarized Glass Made Window to Reduce the Amount of Electricity Usage by Air Condition System
Authors: Imtiaz Sarwar
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Air conditioning in homes may account for one-third of the electricity during period in summer when most of the energy is required in large cities. It is not consuming only electricity but also has a serious impact on environment including greenhouse effect. Circular polarizer filter can be used to selectively absorb or pass clockwise or counter-clock wise circularly polarized light. My research is about putting two circular polarized glasses parallel to each other and make a circular window with it. When we will place two circular polarized glasses exactly same way (0 degree to each other) then nothing will be noticed rather it will work as a regular window through which all light and heat can pass on. While we will keep rotating one of the circular polarized glasses, the angle between the glasses will keep increasing and the window will keep blocking more and more lights. It will completely block all the lights and a portion of related heat when one of the windows will reach 90 degree to another. On the other hand, we can just open the window when fresh air is necessary. It will reduce the necessity of using Air condition too much or consumer will use electric fan rather than air conditioning system. Thus, we can save a significant amount of electricity and we can go green.Keywords: circular polarizer, window, air condition, light, energy
Procedia PDF Downloads 5987671 The Role of Ionic Strength and Mineral Size to Zeta Potential for the Adhesion of P. putida to Mineral Surfaces
Authors: Fathiah Mohamed Zuki, Robert George Edyvean
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Electrostatic interaction energy (∆EEDL) is a part of the Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, which, together with van der Waals (∆EVDW) and acid base (∆EAB) interaction energies, has been extensively used to investigate the initial adhesion of bacteria to surfaces. Electrostatic or electrical double layer interaction energy is considerably affected by surface potential, however it cannot be determined experimentally and is usually replaced by zeta (ζ) potential via electrophoretic mobility. This paper focuses on the effect of ionic concentration as a function of pH and the effect of mineral grain size on ζ potential. It was found that both ionic strength and mineral grain size play a major role in determining the value of ζ potential for the adhesion of P. putida to hematite and quartz surfaces. Higher ζ potential values lead to higher electrostatic interaction energies and eventually to higher total XDLVO interaction energy resulting in bacterial repulsion.Keywords: XDLVO, electrostatic interaction energy, zeta potential, P. putida, mineral
Procedia PDF Downloads 4387670 Management of Interdependence in Manufacturing Networks
Authors: Atour Taghipour
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In the real world each manufacturing company is an independent business unit. These business units are linked to each other through upstream and downstream linkages. The management of these linkages is called coordination which, could be considered as a difficult engineering task. The degree of difficulty of coordination depends on the type and the nature of information exchanged between partners as well as the structure of relationship from mutual to the network structure. The literature of manufacturing systems comprises a wide range of varieties of methods and approaches of coordination. In fact, two main streams of research can be distinguished: central coordination versus decentralized coordination. In the centralized systems a high degree of information exchanges is required. The high degree of information exchanges sometimes leads to difficulties when independent members do not want to share information. In order to address these difficulties, decentralized approaches of coordination of operations planning decisions based on some minimal information sharing have been proposed in many academic disciplines. This paper first proposes a framework of analysis in order to analyze the proposed approaches in the literature, based on this framework which includes the similarities between approaches we categorize the existing approaches. This classification can be used as a research map for future researches. The result of our paper highlights several opportunities for future research. First, it is proposed to develop more dynamic and stochastic mechanisms of planning coordination of manufacturing units. Second, in order to exploit the complementarities of approaches proposed by diverse science discipline, we propose to integrate the techniques of coordination. Finally, based on our approach we proposed to develop coordination standards to guaranty both the complementarity of these approaches as well as the freedom of companies to adopt any planning tools.Keywords: network coordination, manufacturing, operations planning, supply chain
Procedia PDF Downloads 2757669 Synthesis and Characterization of Carboxymethyl Cellulose from Rice Stubble Cellulose
Authors: Rungsinee Sothornvit, Pattrathip Rodsamran
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Rice stubble consists of a high content of cellulose and can be synthesized as a cellulose derivative such as carboxymethyl cellulose (CMC) to value added products from agricultural waste. Therefore, the synthesis conditions and characterization the properties of CMC from rice stubble (CMCr) were investigated. Hemicellulose and lignin were first removed from the rice stubble using 10% NaOH at 55 C for 3 h and 5% NaOCl at 75 C for 15 min, respectively. Rice stubble cellulose was swollen in 30% NaOH and isopropanol as a solvent. The content of chloroacetic acid (5–7 g in 5 g of alkali cellulose), reaction temperature (50 and 70 C) and time (180, 270 and 360 min) were explored to obtain CMC. It was found that synthesis conditions did not affect significantly on moisture content and pH of CMCr. The best quality of CMCr was synthesized by using 7 g of chloroacetic acid and reacted at 50 C for 180 min based on 5 g of rice stubble cellulose. Degree of substitution (DS), viscosity and purity of CMCr were 0.64, 36.03 cP and 90.18 %, respectively. Furthermore, Fourier transform infrared (FT–IR) spectroscopy confirmed the presence of carboxymethyl substituents. CMCr was categorized in commercial scale as a low viscosity material and it can be used as film forming packaging materials for food and pharmaceutical product applications.Keywords: rice stubble, cellulose, carboxymethyl cellulose, degree of substitution, purity
Procedia PDF Downloads 3897668 The Organizational Commitment of the Public Enterprises in Thailand
Authors: Routsukol Sunalai
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The purpose of this study is to examine the impact of public enterprise reform policy on the attributes of organizational commitments in the public energy enterprises in Thailand. It compares three structural types of public energy enterprises: Totally state-owned public enterprises (type I), partially transformed public enterprises (type II), and totally transformed public enterprises (type III), based on the degree of state partially transformed public enterprises (type II), and totally transformed public enterprises (type III),based on the degree of reformed organizations, by analyzing the presence of the desirable attributes of organizational commitment as perceived by employees. Findings indicate that there are statistically significant differences in the level of some dimensions of organizational commitment (affective commitment and normative commitment) between the three types of public energy enterprises. The lack of a structural type difference holds for only continuance commitment. The results also indicate empirical evidence concerning the causal relationship between the antecedents and including organizational commitment also.Keywords: management control, organizational commitment, public enterprises in Thailand, public enterprise reform
Procedia PDF Downloads 2857667 Evaluation of Social Studies Curriculum Implementation of Bachelor of Education Degree in Colleges of Education in Southwestern Nigeria
Authors: F. A. Adesoji, A. A. Ayandele
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There has been a concern over non-responsiveness of educational programme in Nigeria’s higher institutions to adequately meet social needs. The study, therefore, investigated the effectiveness of basic elements of the Social Studies Curriculum, the contributions of the Teacher–Related Variables (TRV) such as qualification, area of specialization, teaching experience, teaching methods, gender and teaching facilities to the implementation of the curriculum (IOC) in the Colleges of Education (COEs). The study adopted the descriptive survey design. Four COEs in Oyo, Osun, Ondo and Lagos States were purposively selected. Stratified sampling technique was used to select 455 Social Studies students and 47 Social Studies lecturers. Stakeholders’ Perception of Social Studies Curriculum (r = 0.86), Social Studies Curriculum Resources scale (r = 0.78) and Social Studies Basic Concepts Test (r = 0.78) were used for data collection. Data were analysed using descriptive statistics, multiple regression, and t-test at 0.05 level of significance. COEs teachers and students rated the elements of the curriculum to be effective with mean scores x̄ =3.02 and x̄ =2.80 respectively; x̄ =5.00 and x̄ = 2.50 being the maximum and minimum mean scores. The finding showed average level of availability (x̄ =1.60), adequacy (x̄ =1.55) and utilization (x̄ =1.64) of teaching materials, x̄ =3.00 and x̄ =1.50 being maximum and minimum mean scores respectively. Academic performance of the students is on average with the mean score of x̄ =51.4775 out of maximum mean score of x̄ =100. The TRV and teaching facilities had significant composite contribution to IOC (F (6,45) = 3.92:R² = 0.26) with 39% contributions to the variance of IOC. Area of specialization (β= 29, t = 2.05) and teaching facilities (β = -25, t = 1.181) contributed significantly. The implementation of bachelor degree in Social Studies curriculum was effective in the colleges of education. There is the need to beef-up the provision of facilities to improve the implementation of the curriculum.Keywords: bachelor degree in social studies, colleges of education in southwestern Nigeria, curriculum implementation, social studies curriculum
Procedia PDF Downloads 3837666 Physical Properties of Nano-Sized Poly-N-Isopropylacrylamide Hydrogels
Authors: Esra Alveroglu Durucu, Kenan Koc
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In this study, we synthesized and characterized nano-sized Poly- N-isopropylacrylamide (PNIPAM) hydrogels. N-isopropylacrylamide (NIPAM) micro and macro gels are known as a thermosensitive colloidal structure, and they respond to changes in the environmental conditions such as temperature and pH. Here, nano-sized gels were synthesized via precipitation copolymerization method. N,N-methylenebisacrylamide (BIS) and ammonium persulfate APS were used as crosslinker and initiator, respectively. 8-Hydroxypyrene-1,3,6- trisulfonic Acid (Pyranine, Py) molecules were used for arranging the particle size and thus physical properties of the nano-sized hydrogels. Fluorescence spectroscopy, atomic force microscopy and light scattering methods were used for characterizing the synthesized hydrogels. The results show that the gel size was decreased with increasing amount of ionic molecule from 550 to 140 nm due to the electrostatic behavior of the ionic side groups of pyranine. Light scattering experiments demonstrate that lower critical solution temperature (LCST) of the gels shifts to the lower temperature with decreasing size of gel due to the hydrophobicity–hydrophilicity balance of the polymer chains.Keywords: hydrogels, lower critical solution temperature, nanogels, poly(n-isopropylacrylamide)
Procedia PDF Downloads 2377665 Development and In vitro Characterization of Diclofenac-Loaded Microparticles
Authors: Prakriti Diwan, S. Saraf
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The present study involves preparation and evaluation of microparticles of diclofenac sodium. The microparticles were prepared by the emulsion solvent evaporation techniques using ethylcellulose polymer. Four different batches of microspheres were prepared by varying the concentration of polymer from 50% to 80% w/w. The microspheres were characterized for drug content, percentage yield and encapsulation efficiency, particle size analysis and surface morphology. Microsphere prepared with high drug content produces higher percentage yield and encapsulation efficiency values. It was observed the increase in concentration of the polymer, increases the mean particle size of the microspheres. The effect of polymer concentration on the in vitro release of diclofenac from the microspheres was also studied. The production microparticles yield showed 98.74%, mean particle size 956.32µm and loading efficiency 97.15%. The results were found that microparticles prepared had slower release than microparticles (p>0.05). Therefore, it may be concluded that drug loaded microparticles are suitable delivery systems for diclofenac sodium.Keywords: diclofenac sodium, emulsion solvent evaporation, ethylcellulose, microparticles
Procedia PDF Downloads 2857664 Phenotype Prediction of DNA Sequence Data: A Machine and Statistical Learning Approach
Authors: Mpho Mokoatle, Darlington Mapiye, James Mashiyane, Stephanie Muller, Gciniwe Dlamini
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Great advances in high-throughput sequencing technologies have resulted in availability of huge amounts of sequencing data in public and private repositories, enabling a holistic understanding of complex biological phenomena. Sequence data are used for a wide range of applications such as gene annotations, expression studies, personalized treatment and precision medicine. However, this rapid growth in sequence data poses a great challenge which calls for novel data processing and analytic methods, as well as huge computing resources. In this work, a machine and statistical learning approach for DNA sequence classification based on $k$-mer representation of sequence data is proposed. The approach is tested using whole genome sequences of Mycobacterium tuberculosis (MTB) isolates to (i) reduce the size of genomic sequence data, (ii) identify an optimum size of k-mers and utilize it to build classification models, (iii) predict the phenotype from whole genome sequence data of a given bacterial isolate, and (iv) demonstrate computing challenges associated with the analysis of whole genome sequence data in producing interpretable and explainable insights. The classification models were trained on 104 whole genome sequences of MTB isoloates. Cluster analysis showed that k-mers maybe used to discriminate phenotypes and the discrimination becomes more concise as the size of k-mers increase. The best performing classification model had a k-mer size of 10 (longest k-mer) an accuracy, recall, precision, specificity, and Matthews Correlation coeffient of 72.0%, 80.5%, 80.5%, 63.6%, and 0.4 respectively. This study provides a comprehensive approach for resampling whole genome sequencing data, objectively selecting a k-mer size, and performing classification for phenotype prediction. The analysis also highlights the importance of increasing the k-mer size to produce more biological explainable results, which brings to the fore the interplay that exists amongst accuracy, computing resources and explainability of classification results. However, the analysis provides a new way to elucidate genetic information from genomic data, and identify phenotype relationships which are important especially in explaining complex biological mechanisms.Keywords: AWD-LSTM, bootstrapping, k-mers, next generation sequencing
Procedia PDF Downloads 1617663 Phenotype Prediction of DNA Sequence Data: A Machine and Statistical Learning Approach
Authors: Darlington Mapiye, Mpho Mokoatle, James Mashiyane, Stephanie Muller, Gciniwe Dlamini
Abstract:
Great advances in high-throughput sequencing technologies have resulted in availability of huge amounts of sequencing data in public and private repositories, enabling a holistic understanding of complex biological phenomena. Sequence data are used for a wide range of applications such as gene annotations, expression studies, personalized treatment and precision medicine. However, this rapid growth in sequence data poses a great challenge which calls for novel data processing and analytic methods, as well as huge computing resources. In this work, a machine and statistical learning approach for DNA sequence classification based on k-mer representation of sequence data is proposed. The approach is tested using whole genome sequences of Mycobacterium tuberculosis (MTB) isolates to (i) reduce the size of genomic sequence data, (ii) identify an optimum size of k-mers and utilize it to build classification models, (iii) predict the phenotype from whole genome sequence data of a given bacterial isolate, and (iv) demonstrate computing challenges associated with the analysis of whole genome sequence data in producing interpretable and explainable insights. The classification models were trained on 104 whole genome sequences of MTB isoloates. Cluster analysis showed that k-mers maybe used to discriminate phenotypes and the discrimination becomes more concise as the size of k-mers increase. The best performing classification model had a k-mer size of 10 (longest k-mer) an accuracy, recall, precision, specificity, and Matthews Correlation coeffient of 72.0 %, 80.5 %, 80.5 %, 63.6 %, and 0.4 respectively. This study provides a comprehensive approach for resampling whole genome sequencing data, objectively selecting a k-mer size, and performing classification for phenotype prediction. The analysis also highlights the importance of increasing the k-mer size to produce more biological explainable results, which brings to the fore the interplay that exists amongst accuracy, computing resources and explainability of classification results. However, the analysis provides a new way to elucidate genetic information from genomic data, and identify phenotype relationships which are important especially in explaining complex biological mechanismsKeywords: AWD-LSTM, bootstrapping, k-mers, next generation sequencing
Procedia PDF Downloads 1477662 Effects of Spray Dryer Atomizer Speed on Casein Micelle Size in Whole Fat Milk Powder and Physicochemical Properties of White Cheese
Authors: Mohammad Goli, Akram Sharifi, Mohammad Yousefi Jozdani, Seyed Ali Mortazavi
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An industrial spray dryer was used, and the effects of atomizer speed on the physicochemical properties of milk powder, the textural and sensory characteristics of white cheese made from this milk powder, were evaluated. For this purpose, whole milk was converted into powder by using three different speeds (10,000, 11,000, and 12,000 rpm). Results showed that with increasing atomizer speed in the spray dryer, the average size of casein micelle is significantly decreased (p < 0.05), whereas no significant effect is observed on the chemical properties of milk powder. White cheese characteristics indicated that with increasing atomizer speed, texture parameters, such as hardness, mastication, and gumminess, were significantly reduced (p < 0.05). Sensory evaluation also revealed that cheese samples prepared with dried milk produced at 12,000 rpm were highly accepted by panelists. Overall, the findings suggested that 12,000 rpm is the optimal atomizer speed for milk powder production.Keywords: spray drying, powder technology, atomizer speed, particle size, white cheese physical properties
Procedia PDF Downloads 4647661 A Review on Application of Waste Tire in Concrete
Authors: M. A. Yazdi, J. Yang, L. Yihui, H. Su
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The application of recycle waste tires into civil engineering practices, namely asphalt paving mixtures and cementbased materials has been gaining ground across the world. This review summarizes and compares the recent achievements in the area of plain rubberized concrete (PRC), in details. Different treatment methods have been discussed to improve the performance of rubberized Portland cement concrete. The review also includes the effects of size and amount of tire rubbers on mechanical and durability properties of PRC. The microstructure behaviour of the rubberized concrete was detailed.Keywords: waste rubber aggregates, microstructure, treatment methods, size and content effects
Procedia PDF Downloads 3197660 Stability and Performance Improvement of a Two-Degree-of-Freedom Robot under Interaction Using the Impedance Control
Authors: Seyed Reza Mirdehghan, Mohammad Reza Haeri Yazdi
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In this paper, the stability and the performance of a two-degree-of-freedom robot under an interaction with a unknown environment has been investigated. The time when the robot returns to its initial position after an interaction and the primary resistance of the robot against the impact must be reduced. Thus, the applied torque on the motor will be reduced. The impedance control is an appropriate method for robot control in these conditions. The stability of the robot at interaction moment was transformed to be a robust stability problem. The dynamic of the unknown environment was modeled as a weight function and the stability of the robot under an interaction with the environment has been investigated using the robust control concept. To improve the performance of the system, a force controller has been designed which the normalized impedance after interaction has been reduced. The resistance of the robot has been considered as a normalized cost function and its value was 0.593. The results has showed reduction of resistance of the robot against impact and the reduction of convergence time by lower than one second.Keywords: impedance control, control system, robots, interaction
Procedia PDF Downloads 422