Search results for: agar plate

Authors: Hamed Djalal

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The aim of this paper is to perform a thermal-hydraulic analysis of the IAEA 10 MW benchmark reactor solving analytically and numerically, by mean of the finite volume method, respectively the steady state and transient forced convection in rectangular narrow channel between two parallel MTR-type fuel plates, imposed under a cosine shape heat flux. A comparison between both solutions is presented to determine the minimal coolant velocity which can ensure a safe reactor core cooling, where the cladding temperature should not reach a specific safety limit 90 °C. For this purpose, a computer program is developed to determine the principal parameter related to the nuclear core safety, such as the temperature distribution in the fuel plate and in the coolant (light water) as a function of the inlet coolant velocity. Finally, a good agreement is noticed between the both analytical and numerical solutions, where the obtained results are displayed graphically.

Keywords: forced convection, pressure drop, thermal hydraulic analysis, vertical heated rectangular channel

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Authors: H. J. Wattimanela, U. S. Passaribu, A. N. T. Puspito, S. W. Indratno

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Molluca Collision Zone is located at the junction of the Eurasian plate, Australian, Pacific, and the Philippines. Between the Sangihe arc, west of the collision zone, and to the east of Halmahera arc is active collision and convex toward the Molluca Sea. This research will analyze the behavior of earthquake occurrence in Molluca Collision Zone related to the distributions of an earthquake in each partition regions, determining the type of distribution of a occurrence earthquake of partition regions, and the mean occurrence of earthquakes each partition regions, and the correlation between the partitions region. We calculate number of earthquakes using partition method and its behavioral using conventional statistical methods. The data used is the data type of shallow earthquakes with magnitudes ≥ 4 SR for the period 1964-2013 in the Molluca Collision Zone. From the results, we can classify partitioned regions based on the correlation into two classes: strong and very strong. This classification can be used for early warning system in disaster management.

Keywords: molluca collision zone, partition regions, conventional statistical methods, earthquakes, classifications, disaster management

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Authors: Zainab D. Abd Ali, Thamir H. Khalaf

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In this paper, the characteristics of electric discharge in gap between two (parallel-plate) dielectric plates are studies, the gap filled with Argon gas in atm pressure at ambient temperature, the thickness of gap typically less than 1 mm and dielectric may be up 10 cm in diameter. One of dielectric plates a sinusoidal voltage is applied with Rf frequency, the other plates is electrically grounded. The simulation in this work depending on Boltzmann equation solver in first few moments, fluid model and plasma chemistry, in one dimensional modeling. This modeling have insight into characteristics of Dielectric Barrier Discharge through studying properties of breakdown of gas, electric field, electric potential, and calculating electron density, mean electron energy, electron current density ,ion current density, total plasma current density. The investigation also include: 1. The influence of change in thickness of gap between two plates if we doubled or reduced gap to half. 2. The effect of thickness of dielectric plates. 3. The influence of change in type and properties of dielectric material (gass, silicon, Teflon).

Keywords: computational diagnostics, Boltzmann equation, electric discharge, electron density

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Authors: S. Dey, T. Mukhopadhyay, S. Adhikari

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This paper presents an exhaustive comparative investigation on sampling techniques of polynomial regression model based stochastic natural frequency of composite plates. Both individual and combined variations of input parameters are considered to map the computational time and accuracy of each modelling techniques. The finite element formulation of composites is capable to deal with both correlated and uncorrelated random input variables such as fibre parameters and material properties. The results obtained by Polynomial regression (PR) using different sampling techniques are compared. Depending on the suitability of sampling techniques such as 2k Factorial designs, Central composite design, A-Optimal design, I-Optimal, D-Optimal, Taguchi’s orthogonal array design, Box-Behnken design, Latin hypercube sampling, sobol sequence are illustrated. Statistical analysis of the first three natural frequencies is presented to compare the results and its performance.

Keywords: composite plate, natural frequency, polynomial regression model, sampling technique, uncertainty quantification

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Authors: Ravinesh C. Deo

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This article investigates through experiments the flow characteristics of plane jets from sharp-edged orifice-plate, beveled-edge and radially contoured nozzle. The first two configurations exhibit saddle-backed velocity profiles while the third shows a top-hat. A vena contracta is found for the jet emanating from orifice at x/h = 3 while the contoured case displays a potential core extending to the range x/h = 5. A spurt in jet pressure on the centerline supports vena contracta for the orifice-jet. Momentum thicknesses and integral length scales elongate linearly with x although the growth of the shear-layer and large-scale eddies for the orifice are greater than the contoured case. The near-field spectrum exhibits higher frequency of the primary eddies that concur with enhanced turbulence intensity. Importantly, highly “turbulent” state of the orifice-jet prevails in the far-field where the spectra confirm more energetic secondary eddies associated with greater flapping amplitude of the orifice-jet.

Keywords: orifice, beveled-edge-orifice, radially contoured nozzle, plane jets

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Authors: Heather Mroz

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Geothermal fluids can provide a nearly unlimited source of renewable energy but are often highly corrosive due to dissolved carbon dioxide (CO2), hydrogen sulphide (H2S), Ammonia (NH3) and chloride ions. The corrosive environment drives material selection for many components, including piping, heat exchangers and pressure vessels, to higher alloys of stainless steel, nickel-based alloys and titanium. The use of these alloys is cost-prohibitive and does not offer the pressure rating of carbon steel. One solution, explosion cladding, has been proven to reduce the capital cost of the geothermal equipment while retaining the mechanical and corrosion properties of both the base metal and the cladded surface metal. Explosion cladding is a solid-state welding process that uses precision explosions to bond two dissimilar metals while retaining the mechanical, electrical and corrosion properties. The process is commonly used to clad steel with a thin layer of corrosion-resistant alloy metal, such as stainless steel, brass, nickel, silver, titanium, or zirconium. Additionally, explosion welding can join a wider array of compatible and non-compatible metals with more than 260 metal combinations possible. The explosion weld is achieved in milliseconds; therefore, no bulk heating occurs, and the metals experience no dilution. By adhering to a strict set of manufacturing requirements, both the shear strength and tensile strength of the bond will exceed the strength of the weaker metal, ensuring the reliability of the bond. For over 50 years, explosion cladding has been used in the oil and gas and chemical processing industries and has provided significant economic benefit in reduced maintenance and lower capital costs over solid construction. The focus of this paper will be on the many benefits of the use of explosion clad in process equipment instead of more expensive solid alloy construction. The method of clad-plate production with explosion welding as well as the methods employed to ensure sound bonding of the metals. It will also include the origins of explosion cladding as well as recent technological developments. Traditionally explosion clad plate was formed into vessels, tube sheets and heads but recent advances include explosion welded piping. The final portion of the paper will give examples of the use of explosion-clad metals in geothermal energy recovery. The classes of materials used for geothermal brine will be discussed, including stainless steels, nickel alloys and titanium. These examples will include heat exchangers (tube sheets), high pressure and horizontal separators, standard pressure crystallizers, piping and well casings. It is important to educate engineers and designers on material options as they develop equipment for geothermal resources. Explosion cladding is a niche technology that can be successful in many situations, like geothermal energy recovery, where high temperature, high pressure and corrosive environments are typical. Applications for explosion clad metals include vessel and heat exchanger components as well as piping.

Keywords: clad metal, explosion welding, separator material, well casing material, piping material

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Authors: Supaporn Wimonchailerk

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This research aims to study how to design and create the media to promote Thai cuisine. The study used qualitative research methods by using in-depth interview 3 key informants who have experienced in the production of food or cooking shows in television programs with an aspect of acknowledging Thai foods. The results showed that visual presentation is divided into four categories. First, the light meals should be presented in details via the close-up camera with lighting to make the food look more delicious. Then the curry presentation should be arranged a clear and crisp light focus on a colorful curry paste. Besides the vision of hot steam floating from the plate and a view of curry spread on steamed rice can call great attentions. Third, delivering good appearances of the fried or spicy foods, the images must allow the audiences to see the shine of the coat covering the texture of the food and the colorful of the ingredients. Fourth, the presentation of sweets is recommended to focus on details of food design, composition, and layout.

Keywords: media production, television, promote, Thai cuisine

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Authors: Arun Jyothi Bheemagani, Chakrapani Pullagummi, Anupalli Roja Rani

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Exploration of the chemical constituents of the plants and pharmacological screening may provide us the basis for the development of novel agents. Plants have provided us some of the very important life saving drugs used in the modern medicine. The aim of our work was to screen the phytochemical constituents and antimicrobial and antioxidant activities of methanol extract of leaves of Annona cherimola Mill plant from Tirumala forest, Tirupathi. It was originally called Chirimuya by the Inca people who lived where it was growing in the Andes of South America, is an edible fruit-bearing species of the genus Annona from the family Annonaceae. Annona cherimola Mill is a multipurpose tree with edible fruits and is one of the sources of the medicinal products. The antibacterial activity was measured by agar well diffusion method; the diameter of the zone of bacterial growth inhibition was measured after incubation of plates. The inhibitory effect was studied against the pathogenic bacteria (Klebsiella pneumonia, Bacillus subtilis, Staphylococcus aureus and Escherichia coli (E. coli). Antioxidant assays were also performed for the same extracts by spectrophotometric methods using known standard antioxidants as reference. The studied plant extracts were found to be very effective against the pathogenic microorganisms tested. The methanolic extract of Annona cherimola Mill from showed maximum activity against Escherichia coli and Staphylococcus aureus and the least concentration required showing the activity was 0.5mg/ml. Phytochemical screening of the plants revealed the presence of flavonoids, alkaloids, steroids and carbohydrates. Good presence of antioxidants was also found in the methanolic extracts.

Keywords: annona cherimola, phytochemicals, antioxidant and antibacterial activity, methanol extract

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Authors: Abdullahi Mohammed

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The microbial quality of beef and mutton sold in four major markets of Bauchi metropolis was assessed in order to assist in ascertaining safety. Shops were selected from 'Muda Lawal', 'Yelwa', 'Wunti', and 'Gwallameji' markets. The total bacterial count was used as index of quality. A total of thirty two (32) samples were collected in two successive visits. The samples were packed and labelled in a sterile polythene bags for transportation to the laboratory. Microbial analysis was carried out immediately upon arrival under a septic condition, where aerobic plate was used in determining the microbial load. Result showed that beef and mutton from Gwallameji had the highest bacterial count of 9.065 X 105 cfu/ml and 8.325 X 105 cfu/ml for beef and mutton respectively followed by Wunti market (6.95 X 105 beef and 4.838 X 105 motton) and Muda Lawal (4.86 X 105 cfu/ml beef and 5.998 X 105 cfu/ml mutton). Yelwa had 5.175 X 105 and 5.30 X 105 for beef and mutton respectively. Bacterial species isolated from the samples were Escherichia coli, Salmonella spp, Streptococcus species and Staphylococcus species. However, results obtained from all markets showed that there was no significant differences between beef and mutton in terms of microbial quality.

Keywords: beef, mutton, salmonella, sterile

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Authors: Gafar Bamigbade, Adebunkola Omemu

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“Ogi” is a fermented cereal gruel prepared from maize (Zea mays), millet (Pennisetum typhoideum) or guinea corn (Sorghum bicolour). It could be boiled to give a thicker consistency wrapped in leaf allowed to cool and set to a gel known as “eko”. The objective of this study is to determine the amylase activities of mould associated with the spoilage of Ogi and eko. Moulds were isolated from spoilt Ogi and eko samples using standard microbiological procedures. The isolate was then screened for amylase production using starch agar medium. Positive isolates were used for amylase production by solid state fermentation (SFF) using rice bran as the medium. An alpha-amylase and glucoamylase activity of the crude enzyme was determined using the DNS method. The mean mold Population ranged from 1.15 X 105cfu/g for raw Ogi to 6.25 X 105cfu/g for Eko (wrapped in Leaves). Twenty-seven (27) moulds isolated from the sample include A. niger, A. flavus, A. fumigatus, Rhizopus species and Penicillium species. Aspergillus flavus had the highest percentage (51.9%) of incidence while Penicillium species had the least (3.7%). Out of the 27 isolates screened, 19 were found to be amylase positive by showing a clear zone around their colony after flooding with iodine solution. Diameter of clear zone ranged from 3.00mm (Aspergillus niger, C4) to 22.00mm (Aspergillus flavus, A1). Aspergillus niger isolated from spoilt Eko wrapped in leaf has the highest percentage alpha-amylase activity (30.8%) and Aspergillus flavus isolated from spoilt raw ogi has the lowest activity (11.4%). Aspergillus niger isolated from spoilt Eko wrapped in nylon produces the highest glucoamylase activity (240U/ml) while penicillium specie isolated from spoilt cooked ogi has the lowest activity (100U/ml). This study shows that moulds associated with spoilage of ogi and eko can produce amylase.

Keywords: glucoamylase, alpha amylase, ogi, eko

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Authors: D Bhargavi, J. Sharath Kumar Reddy

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The present investigation has been undertaken to assess the effect of viscous dissipation and axial conduction on forced convection heat transfer in the entrance region of a parallel plate channel with the porous insert attached to both walls of the channel. The flow field is unidirectional. Flow in the porous region corresponds to Darcy-Brinkman model and the clear fluid region to that of plane Poiseuille flow. The effects of the parameters Darcy number, Da, Peclet number, Pe, Brinkman number, Br and a porous fraction γ_p on the local heat transfer coefficient are analyzed graphically. Effects of viscous dissipation employing the Darcy model and the clear fluid compatible model have been studied.

Keywords: porous material, channel partially filled with a porous material, axial conduction, viscous dissipation

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Authors: Mohammed W. Sulaiman, Chi-Chuan Wang

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Due to the improved performance of electronic systems, the demand for electronic cooling devices with high heat dissipation has increased. This research evaluates plain microchannel cold plates with a gap above the microchannels. The present study examines the effect of the gap above straight fin microchannels in the cold plate using the dielectric Novec 7000 as a working fluid. The experiments compared two transparency cover with the same geometry and dimension for the test section. One has a gap above the microchannels (GAM) 1/3 of fin height, and another one with no gap above the microchannels (NGAM); the mass flux ranges from 25 to 260 kg/m2s, while the heat flux spans from 50 to 150 W/cm2. The results show quite an improvement in performance with this space gap above the microchannels. The test results showed that the design of the GAM shows a superior heat transfer coefficient (HTC), up 90% than that of NCBM. The GAM design has a much lower pressure drop by about 7~24% compared to the NGAM design at different mass flux and heat flux at the fully liquid inlet. The proposed space gap of 0.33% of fin height above the microchannels enables the surface temperature to decrease by around 3~7 °C compared to no gap above the microchannels, especially at high heat fluxes.

Keywords: microchannels, pressure drop, enhanced performance, electronic cooling, gap

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Authors: Hyoun Joong Kim, Jin Woo Jun, Sib Sankar Giri, Cheng Chi, Saekil Yun, Sang Guen Kim, Sang Wha Kim, Jeong Woo Kang, Se Jin Han, Se Chang Park

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Vibrio corallilyticus is a well-known pathogen of coral. It is also infectious to a variety of shellfish species, including Pacific oyster (Crassostrea gigas) larvae. V. corallilyticus is remained to be a major constraint in marine bivalve aquaculture practice, especially in artificial seed production facility. Owing to the high mortality and contagious nature of the pathogen, large amount of antibiotics has been used for disease prevention and control. However, indiscriminate use of antibiotics may result in food and environmental pollution, and development of antibiotic resistant strains. Therefore, eco-friendly disease preventative measures are imperative for sustainable bivalve culture. The present investigation proposes the application of bacteriophage (phage) as an effective alternative method for controlling V. corallilyticus infection in marine bivalve hatcheries. Isolation of phages from sea water sample was carried out using drop or double layer agar methods. The host range, stability and morphology of the phage isolates were studied. In vivo phage efficacy to prevent V. corallilyticus infection in oyster larvae was also performed. The isolated phages, named pVco-5 and pVco-7 was classified as a podoviridae and pVco-14, was classified as a siphoviridae. Each phages were infective to four strains of seven V. corallilyticus strains tested. When oyster larvae were pre-treated with the phage before bacterial challenge, mortality of the treated oyster larvae was lower than that in the untreated control. This result suggests that each phages have the potential to be used as therapeutic agent for controlling V. corallilyticus infection in marine bivalve hatchery.

Keywords: bacteriophage, Vibrio coralliilyticus, Oyster larvae, mortality

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Authors: Ajay Krishnamurthy, Mariyappan Mahesh Kumar, Sellamuthu Periyar Selvam

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Fruits are considered as functional foods due to the presence of various bioactive compounds available such as polyphenols, which are beneficial to health when consumed as part of our diet. The primary objective of this study was to analyze the various functional groups present in ethanolic extracts of Hylocereus undatus and Garcinia indica and also measure their antibacterial and antioxidant potential respectively thereby affirming its nutraceutical potential. To fulfill our objective, a Fourier - transform Infrared Spectroscopy (FTIR) was conducted for functional group analysis, Total Phenolic Content and DPPH free radical scavenging activity for measuring it anti-oxidant potential and agar-well diffusion assay for antibacterial potential. On careful observation and analysis of the spectrum it was found that both the fruit extracts contain similar compounds viz. Phenols, Alkanes, Alkenes, Aldehydes, Ketones, Carboxylic Acid and Amines. Total phenolic content of H.undatus and G.indica was estimated to be (26.85 ± 1.84 mg GAE/100g) and (32.84 ± 1.63 mg GAE/100g) respectively which corresponds to an inhibition of 84% and 81% respectively. H.undatus shows an inhibition of (3.4 ± 2.1mm) in gram-positive and (4.2 ± 2.24mm) in gram-negative organism on the other hand G.indica shows (2.1 ± 0.98mm) in gram-positive and (3.1 ± 1.44mm) in gram negative. The presence of such diverse compounds in the fruits helps us to understand the necessity for the inclusion of fruits in our daily diet and also helps the pharmaceutical industry in realizing the importance of exotic fruits as a potential nutraceutical.

Keywords: DPPH, fourier-transform infrared spectroscopy (FTIR), Hylocereus undatus, Garcinia indica

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Authors: Farzad Vakili-Farahani, Joern Lungershausen, Kilian Wasmer

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Wobbled laser beam welding, fast oscillations of a tiny laser beam within a designed path (weld geometry) during the laser pulse illumination, opens new possibilities to improve the marco-to micro-manufacturing process. The present work introduces the wobbled laser beam welding as a robust welding strategy for improving macro-to micro-fabrication process, e.g., the laser processing for gap-bridging and packaging industry. The typical requisites and relevant equipment for the development of a wobbled laser processing unit are addressed, including a suitable laser source, light delivery system, optics, proper beam deflection system and the design geometry. In addition, experiments have been carried out on titanium plate to compare the results of wobbled laser welding with conventional pulsed laser welding. As compared to the pulsed laser welding, the wobbled laser welding offers a much greater fusion area (i.e. additional molten material) while minimizing the HAZ and provides a better confinement of the material microstructural changes.

Keywords: wobbled laser beam welding, wobbling function, beam oscillation, micro welding

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Authors: DucTho Le, Duy Kien Dao, Quoc Tinh Bui, Haidang Phan

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The article is concerned with the motion of ultrasonic guided waves in a unidirectional fiber-reinforced composite plate under acoustic sources. Such unidirectional composite material has orthotropic elastic properties as it is very stiff along the fibers and rather compliant across the fibers. The dispersion equations of free Lamb waves propagating in an orthotropic layer are derived that results in the dispersion curves. The connection of these equations to the Rayleigh-Lamb frequency relations of isotropic plates is discussed. By the use of reciprocity in elastodynamics, closed-form solutions of elastic wave motions subjected to time-harmonic loads in the layer are computed in a simple manner. We also consider the problem of Lamb waves generated by a set of time-harmonic sources. The obtained computations can be very useful for developing ultrasound-based methods for nondestructive evaluation of composite structures.

Keywords: lamb waves, fiber-reinforced composite plates, dispersion equations, nondestructive evaluation, reciprocity theorems

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Authors: Boutemak Khalida, Dahmani Siham

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Garden cress (Lepidium Sativum L.) belonging to the family Brassicaceae, is edible growing annual herb. Its various parts (roots, leaves and seeds) have been used to treat various human ailments. Its seed extracts have been screened for various biological activities like hypotensive, antimicrobial, bronchodilator, hypoglycaemic and antianemic. The aim of the present study is to optimize the process parameters (cellulase concentration and incubation time) of enzymatic pre-treatment of the garden cress seeds and to evaluate the effect of cellulase pre-treatment of the crushed seeds on the oil yield, physico-chemical properties and antibacterial activity and comparing to non-enzymatic method. The optimum parameters of cellulase pre-treatment were as follows: cellulase of 0,1% w/w and incubation time of 2h. After enzymatic pre-treatment, the oil was extracted by n-hexane for 1.5 h, the oil yield was 4,01% for cellulase pre-treatment as against 10,99% in the control sample. The decrease in yield might be caused a result of mucilage. Garden cress seeds are covered with a layer of mucilage which gels on contact with water. At the same time, the antibacterial activity was carried out using agar diffusion method against 4 food-borne pathogens (Escherichia coli, Salmonella typhi,Staphylococcus aureus, Bacillus subtilis). The results showed that bacterial strains are very sensitive to the oil with cellulase pre-treatment. Staphylococcus aureus is extremely sensitive with the largest zone of inhibition (40 mm), Escherichia coli and salmonella typhi had a very sensitive to the oil with a zone of inhibition (26 mm). Bacillus subtilizes is averagely sensitive which gave an inhibition of 16 mm. But it does not exhibit sensivity to the oil without enzymatic pre-treatment with a zone inhibition (< 8 mm). Enzymatic pre-treatment could be useful for antimicrobial activity of the oil, and hold a good potential for use in food and pharmaceutical industries.

Keywords: Lepidium sativum L., cellulase, enzymatic pretreatment, antibacterial activity.

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Authors: José Francisco Urrutia Reyes, Judith Espinosa Real

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This paper is meant to re-examine the role of street art in the contemporary world. By studying this form of art in Brussels, it can be explained how murals show the socio-political reality of a given community and influence on its interaction. Through the definitions of street art, murals and street artists, and analysing their role in Brussels, it is possible to understand how this counter culture movement serves as an engine of social development, as it interacts with its surroundings sending a clear message to a wider audience. Street art impacts on its environment because it interacts with the people who occupies the day-to-day public space. This has proven to be effective in the arouse of social consciousness, up to the point of being adopted by the government of Brussels to promote social movements such as the AIDS-HIV campaign along with the Plate-Forme Prévention Sida. It can be concluded that street art has evolved since its vandalic beginnings, to become a form of art that has not lost it counter official status, but now has a critical vision that can promote social awakening. Street art is now a global trend that uses visual inputs to create a positive impact.

Keywords: street art, Brussels, social impact, political perspective

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Authors: Sandeep Singh Sandhua, Karanvir Singh Ghuman, Arun Kumar

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Stellite 21 is cobalt based super alloy used in improving the wear performance of stainless steel engineering components subjected to harsh environmental conditions. This piece of research focuses on the wear analysis of satellite 21 cladded on AISI 304 L substrate using SMAW process. Bead on plate experiments were carried out by varying current and electrode manipulation techniques to optimize the dilution and microhardness. 80 Amp current and weaving technique was found to be optimum set of parameters for overlaying which were further used for multipass multilayer cladding of AISI 304 L substrate. The wear performance was examined on pin on dics wear testing machine under room temperature conditions. The results from this study show that Stellite 21 overlays show a significant improvement in the frictional wear resistance after TIG remelting. It is also established that low dilution procedures are important in controlling the metallurgical composition of these overlays which has a consequent effect in enhancing hardness and wear resistance of these overlays.

Keywords: surfacing, stellite 21, dilution, SMAW, frictional wear, micro-hardness

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Authors: Huilan Yao, Huaixin Zhang

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Simulations of the transition flow of model propellers are important for predicting hydrodynamic performance and studying scale effects. In this paper, the transition flow of a model propeller under different loadings are simulated using a transition model provided by STAR-CCM+, and the influence of turbulence intensity (TI) on the transition, especially friction and pressure components of propeller performance, was studied. Before that, the transition model was applied to simulate the transition flow of a flat plate and an airfoil. Predicted transitions agree well with experimental results. Then, the transition model was applied for propeller simulations in open water, and the influence of TI was studied. Under the heavy and moderate loadings, thrust and torque of the propeller predicted by the transition model (different TI) and two turbulence models are very close and agree well with measurements. However, under the light loading, only the transition model with low TI predicts the most accurate results. Above all, the friction components of propeller performance predicted by the transition model with different TI have obvious difference.

Keywords: transition flow, model propellers, hydrodynamic performance, numerical simulation

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Authors: Aliza Lee, Mark Wilt, John Bonk, Scott Floyd, Bradley Hoffman, Karen Uchmanowicz

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Bipartite medial cuneiforms are relatively rare but may play a significant role in biomechanical and gait abnormalities. It is believed that a bipartite medial cuneiform may alter the available range of motion due to its larger morphological variant, thus limiting the metatarsal plantarflexion needed to achieve adequate hallux dorsiflexion for normal gait. Radiographic and clinical assessments were performed on 2 patients who reported foot pain along the first ray. Both patients had visible bipartite medial cuneiforms on MRI. Using gait plate and Metascan™ analysis, both were noted to have four measurements far beyond the expected range. Medial and lateral heel peak pressure, hallux peak pressure, and 1st metatarsal peak pressure were all noted to be increased. These measurements are believed to be increased due to the hindrance placed on the available ROM of the 1st ray by the increased size of the medial cuneiform. A larger patient population would be needed to fully understand this developmental anomaly.

Keywords: bipartite medial cuneiforms, cuneiform, developmental anomaly, gait abnormality

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Authors: Yixin Yan, Miao Yan, Irini Angelidaki, Ioannis Fotidis

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Ammonia, which derives from the degradation of urea and protein-substrates, is the major toxicant of the commercial anaerobic digestion reactors causing loses of up to 1/3 of their practical biogas production, which reflects directly on the overall revenue of the plants. The current experimental work is aiming to alleviate the ammonia inhibition in anaerobic digestion (AD) process by developing an innovative bioaugmentation method of ammonia tolerant methanogenic consortia. The ammonia tolerant consortia were cultured in batch reactors and immobilized together with biochar in agar (customized inocula). Three continuous stirred-tank reactors (CSTR), fed with the organic fraction of municipal solid waste at a hydraulic retention time of 15 days and operated at thermophilic (55°C) conditions were assessed. After an ammonia shock of 4 g NH4+-N L-1, the customized inocula were bioaugmented into the CSTR reactors to alleviate ammonia toxicity effect on AD process. Recovery rate of methane production and methanogenic activity will be assessed to evaluate the bioaugmentation performance, while 16s rRNA gene sequence will be used to reveal the difference of microbial community changes through bioaugmentation. At the microbial level, the microbial community structures of the four reactors will be analysed to find the mechanism of bioaugmentation. Changes in hydrogen formation potential will be used to predict direct interspecies electron transfer (DIET) between ammonia tolerant methanogens and syntrophic bacteria. This experimental work is expected to create bioaugmentation inocula that will be easy to obtain, transport, handled and bioaugment in AD reactors to efficiently alleviate the ammonia toxicity, without alternating any of the other operational parameters including the ammonia-rich feedstocks.

Keywords: artisanal fishing waste, acidogenesis, volatile fatty acids, pH, inoculum/substrate ratio

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Authors: Elena B. Cherepetskaya, Alexander A.Karabutov, Vladimir A. Makarov, Elena A. Mironova, Ivan A. Shibaev

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In our study, the object of laser ultrasonic testing was plane-parallel plate of shungit (length 41 mm, width 31 mm, height 15 mm, medium exchange density 2247 kg/m3). We used laser-ultrasonic defectoscope with wideband opto-acoustic transducer in our investigation of the velocities of longitudinal and shear elastic ultrasound waves. The duration of arising elastic pulses was less than 100 ns. Under known material thickness, the values of the velocities were determined by the time delay of the pulses reflected from the bottom surface of the sample with respect to reference pulses. The accuracy of measurement was 0.3% in the case of longitudinal wave velocity and 0.5% in the case of shear wave velocity (scanning pitch along the surface was 2 mm). On the base of found velocities of elastic waves, local elastic moduli of shungit (Young modulus, shear modulus and Poisson's ratio) were uniquely determined.

Keywords: laser ultrasonic testing , local elastic moduli, shear wave velocity, shungit

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Authors: David Polcari, Samuel C. Perry, Loredano Pollegioni, Matthias Geissler, Janine Mauzeroll

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ᴅ-serine acts as an endogenous co-agonist for N-methyl-ᴅ-aspartate receptors in neuronal synapses. This makes it a key component in the development and function of a healthy brain, especially given its role in several neurodegenerative diseases such as Alzheimer’s disease and dementia. Despite such clear research motivations, the primary site and mechanism of ᴅ-serine release is still currently unclear. For this reason, we are developing a biosensor for the detection of ᴅ-serine utilizing a microelectrode in combination with a ᴅ-amino acid oxidase enzyme, which produces stoichiometric quantities of hydrogen peroxide in response to ᴅ-serine. For the fabrication of a biosensor with good selectivity, we use a permselective poly(meta-phenylenediamine) film to ensure only the target molecule is reacted, according to the size exclusion principle. In this work, we investigated the effect of the electrodeposition conditions used on the biosensor’s response time and selectivity. Careful optimization of the fabrication process allowed for enhanced biosensor response time. This allowed for the real time sensing of ᴅ-serine in a bulk solution, and also provided in means to map the efflux of ᴅ-serine in real time. This was done using scanning electrochemical microscopy (SECM) with the optimized biosensor to measure localized release of ᴅ-serine from an agar filled glass capillary sealed in an epoxy puck, which acted as a model system. The SECM area scan simultaneously provided information regarding the rate of ᴅ-serine flux from the model substrate, as well as the size of the substrate itself. This SECM methodology, which provides high spatial and temporal resolution, could be useful to investigate the primary site and mechanism of ᴅ-serine release in other biological samples.

Keywords: ᴅ-serine, enzymatic biosensor, microelectrode, scanning electrochemical microscopy

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Authors: Ahmad Nazrun Shuid, Isa Naina Mohamed, Nurul Izzah Ibrahim, Norazlina Mohamed

Abstract:

Studies have shown that oral tocotrienol, a potent vitamin E, promoted fracture healing of osteoporotic bone. In this study, tocotrienol was combined with a polymer carrier (PLGA), and injected to the fracture site. The slow and constant release of tocotrienol particles would promote fracture healing of post-menopausal osteoporosis rat model. Fracture healing was assessed using micro-CT. Twenty-four Sprague-Dawley rats were ovariectomised or sham-operated and the left tibiae were fractured and fixed with plate and screws. The fractures were created at the upper third of the left tibiae. The rats were divided into 3 groups: sham-operated (SO), ovariectomised-control (OVxC) and PLGA-incorporated tocotrienol treatment (OVx + TT) groups. After 4 weeks, the OVx + TT group showed significantly better callus fracture healing than the OVxC group. In conclusion, tocotrienol-incorporated PLGA was able to promote fracture healing of osteoporotic bone.

Keywords: osteoporosis, micro-CT, tocotrienol, PLGA, fracture

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Authors: Sebaa H., Cherifi F., Djabeur Abderrezak M.

Abstract:

Argania spinosa, Sapotaceae sole representative in Algeria and Morocco; hence it is endemic in these regions. However, it is a recognised oil, forage, and timber tree highly adapted to aridity. The exploitation of the argan fruits produces considerable amounts of under or related products. These products, such as the endocarps of a fruit, recuperated after the use of kernels to extract oil. This research studies in detail the contents of total phenolic content was determined by Folin Ciocalteu reagent and Flavonoids by aluminum chloride colorimetric assay). Antioxidant activity of extracts was expressed as the percentage of DPPH radical inhibition and IC50 values (μg/mL). Antimicrobial activity evaluated using agar disk diffusion method against reference Pseudomonas aeruginosa ATTC 27453, Escherichia coli ATCC 23922. Immature endocarps showed a higher polyphenol content than mature endocarps. The total phenolic content in immature endocarps was found to vary from 983,75+ /- 0.45 to 980,1 +/- 0.43 mg gallic acid equivalents/g dry weight, whereas in mature endocarps, the polyphenol content ranged from 100,58 mg/g +/- 0.42 to 105 +/- 0.55% mg gallic acid equivalent / g dry weight. The flavonoid content was 16.5 mg equivalent catechin/g dry weight and 9.81mg equivalent catechin /g dry weight for immature and mature endocarp fruits, respectively. DPPH assay of the endocarps extract yielded a half-maximal effective concentration (IC50) value in the immature endocarps (549.33 μg/mL) than in mature endocarps (322 μg/mL). This result can be attributed to the higher phenolics and flavonoid compounds in the immature endocarps. Methanol extract of immature endocarps exhibited antibacterial activity against E.colie (inhibition zone, 11mm).

Keywords: antioxidant activity, antimicrobial activity, total phenolic content, DPPH assay

Procedia PDF Downloads 113

Authors: Nichanant Sermsri, Chananchida Yuktirat

Abstract:

This research was the experimental research. Its purpose was to find out how coconut shells can be adapted to be equipment for foot and calf reflexology. The sample group was 58 female street vendors in Thewet Market, Dusit District, Bangkok, selected by selection criteria and voluntary. The data collecting tool in this research was the Visual Analogue Scale. The massaging tool made from coconut shells (designed and produced by the research team) was the key equipment for this research. The duration of the research was 1 month. The research team assessed the level of exhaustion and heart rate among sample group before and after the massage, then analyzed the data by mean, standard deviation and paired sample t-test. We found out from the research that 1) The level of exhaustion decreased 4.529 levels after the massage. The standard deviation was 1.6195. The heart rates went down 11.67 times/minute. The standard deviation was 6.742. 2) The level of exhaustion and heart rate after the massage decreased with the statistically significance at 0.01.

Keywords: foot reflexology, massaging plate, coconut shells, ecological sciences

Procedia PDF Downloads 186

Authors: S. A. Naeini, M. Hamidzadeh

Abstract:

Today, with the daily advancement of geotechnical engineering on soil improvement and modification of the physical properties and shear strength of soil, it is now possible to construct structures with high-volume and high service load on loose sandy soils. One of such methods is using micropiles, which are mostly used to control asymmetrical subsidence, increase bearing capacity, and prevent soil liquefaction. This study examined the improvement of Anzali's saturated loose silty sand using 192 micropiles with a length of 8 meters and diameter of 75 mm. Bandar-e Anzali is one of Iran's coastal populated cities which are located in a high-seismicity region. The effects of the insertion of micropiles on prevention of liquefaction and improvement of subsidence were examined through comparison of the results of Standard Penetration Test (SPT) and Plate Load Test (PLT) before and after implementation of the micropiles. The results show that the SPT values and the ultimate bearing capacity of silty sand increased after the implementation of the micropiles. Therefore, the installation of micropiles increases the strength of silty sand improving the resistance of soil against liquefaction.

Keywords: soil improvement, silty sand, micropiles, SPT, PLT, strength

Procedia PDF Downloads 192

Authors: S. A. Hashemi, A. Khoshraftar

Abstract:

This paper presents the influence of the vertical seismic component on the non-linear dynamics analysis of three different structures. The subject structures were analyzed and designed according to recent codes. This paper considers three types of buildings: 5-, 10-, and 15-story buildings. The non-linear dynamics analysis of the structures with assuming elastic-perfectly-plastic behavior was performed using Ram Perform-3D software; the horizontal component was taken into consideration with and without the incorporation of the corresponding vertical component. Dynamic responses obtained for the horizontal component acting alone were compared with those obtained from the simultaneous application of both seismic components. The results show that the effect of the vertical component of the ground motion may increase the axial load significantly in the interior columns and consequently, the stories. The plastic mechanisms would be changed. The P-Delta effect is expected to increase. The punching base plate shear of the columns should be considered. Moreover, the vertical component increases the input energy when the structures exhibit inelastic behavior and are taller.

Keywords: inelastic behavior, non-linear dynamic analysis, steel structure, vertical component

Procedia PDF Downloads 312

Authors: Davender Kumar

Abstract:

Aim: It is important for the orthodontist to be familiar with the sliding resistance (SR) generated by the ligation method used during the space closure phase with sliding mechanics. To determine new, experimental non-conventional (slide) ligature demonstrates less friction in vitro when compared other ligatures on the market. Methods: Experimental in vitro were carried out to test the performance of the low-friction system with regard to assess the forces released by different bracket–ligature systems with bonded in iron plate mounted on an Instron machine. Results: The outcomes of experimental testing showed that the combination of the low-friction ligatures with the super elastic nickel-titanium and SS wires produced a significantly smaller amount of binding at the bracket/arch wire/ligature unit when compared to conventional elastomeric ligatures. Conclusion: The biomechanical consequences of the use of low-friction ligatures were shorter duration of orthodontic treatment during the levelling and aligning phase, concurrent dentoalveolar expansion of the dental arch, and the possibility of using biologically adequate orthodontic forces.

Keywords: archwire, bracket, friction, ligation

Procedia PDF Downloads 321