Search results for: cohesive zone
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1739

Search results for: cohesive zone

1229 Amylase Activities of Mould Isolated from Spoilt Ogi and Eko: Two (2) Fermented Maize Products

Authors: Gafar Bamigbade, Adebunkola Omemu

Abstract:

“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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1228 Indoor and Outdoor Forest Farming for Year-Round Food and Medicine Production, Carbon Sequestration, Soil-Building, and Climate Change Mitigation

Authors: Jerome Osentowski

Abstract:

The objective at Central Rocky Mountain Permaculture Institute has been to put in practice a sustainable way of life while growing food, medicine, and providing education. This has been done by applying methods of farming such as agroforestry, forest farming, and perennial polycultures. These methods have been found to be regenerative to the environment through carbon sequestration, soil-building, climate change mitigation, and the provision of food security. After 30 years of implementing carbon farming methods, the results are agro-diversity, self-sustaining systems, and a consistent provision of food and medicine. These results are exhibited through polyculture plantings in an outdoor forest garden spanning roughly an acre containing about 200 varieties of fruits, nuts, nitrogen-fixing trees, and medicinal herbs, and two indoor forest garden greenhouses (one Mediterranean and one Tropical) containing about 50 varieties of tropical fruits, beans, herbaceous plants and more. While the climate zone outside the greenhouse is 6, the tropical forest garden greenhouse retains an indoor climate zone of 11 with near-net-zero energy consumption through the use of a climate battery, allowing the greenhouse to serve as a year-round food producer. The effort to source food from the forest gardens is minimal compared to annual crop production. The findings at Central Rocky Mountain Permaculture Institute conclude that agroecological methods are not only beneficial but necessary in order to revive and regenerate the environment and food security.

Keywords: agroecology, agroforestry, carbon farming, carbon sequestration, climate battery, food security, forest farming, forest garden, greenhouse, near-net-zero, perennial polycultures

Procedia PDF Downloads 420
1227 Experimental Study on Weak Cohesion Less Soil Using Granular Piles with Geogrid Reinforcement

Authors: Sateesh Kumar Pisini, Swetha Priya Pisini

Abstract:

Granular piles are becoming popular as a technique of deep ground improvement not only in soft cohesive soils but also in loose cohesionless deposits. The present experimental study has been carried out on granular piles in sand (loose sand and medium dense sand i.e. relative density at 15% and 30%) with geogrid reinforcement. In this experimental study, a group of five piles installed in sand (at different spacing i.e s = 2d, 3d and 4d) the length and diameter of the pile (L = 0.4 m and d= 50 mm) kept as same for all series of experiments. Geogrid reinforcement is provided on granular piles with a limited number of laboratory tests. It has been conducted in laboratory to study the behavior of a granular pile with reinforced geogrid layers supporting a square footing at different s/d ratios. The influence of geogrid layers providing on granular piles investigated through model tests. In this paper the experimental study carried out results in significant increase in load carrying capacity and decrease in settlement reduction of the weak cohesionless soil. Also, the behavior of load carrying capacity and settlement with changing the s/d ratio has been carried out through a parametric study.

Keywords: granular piles, cohesionless soil, geogrid reinforcement, load carrying capacity

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1226 Identification of Groundwater Potential Zones Using Geographic Information System and Multi-Criteria Decision Analysis: A Case Study in Bagmati River Basin

Authors: Hritik Bhattarai, Vivek Dumre, Ananya Neupane, Poonam Koirala, Anjali Singh

Abstract:

The availability of clean and reliable groundwater is essential for the sustainment of human and environmental health. Groundwater is a crucial resource that contributes significantly to the total annual supply. However, over-exploitation has depleted groundwater availability considerably and led to some land subsidence. Determining the potential zone of groundwater is vital for protecting water quality and managing groundwater systems. Groundwater potential zones are marked with the assistance of Geographic Information System techniques. During the study, a standard methodology was proposed to determine groundwater potential using an integration of GIS and AHP techniques. When choosing the prospective groundwater zone, accurate information was generated to get parameters such as geology, slope, soil, temperature, rainfall, drainage density, and lineament density. However, identifying and mapping potential groundwater zones remains challenging due to aquifer systems' complex and dynamic nature. Then, ArcGIS was incorporated with a weighted overlay, and appropriate ranks were assigned to each parameter group. Through data analysis, MCDA was applied to weigh and prioritize the different parameters based on their relative impact on groundwater potential. There were three probable groundwater zones: low potential, moderate potential, and high potential. Our analysis showed that the central and lower parts of the Bagmati River Basin have the highest potential, i.e., 7.20% of the total area. In contrast, the northern and eastern parts have lower potential. The identified potential zones can be used to guide future groundwater exploration and management strategies in the region.

Keywords: groundwater, geographic information system, analytic hierarchy processes, multi-criteria decision analysis, Bagmati

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1225 Push-Out Bond Strength of Two Root-End Filling Materials in Root-End Cavities Prepared by Er,Cr: YSGG Laser or Ultrasonic Technique

Authors: Noushin Shokouhinejad, Hasan Razmi, Reza Fekrazad, Saeed Asgary, Ammar Neshati, Hadi Assadian, Sanam Kheirieh

Abstract:

This study compared the push-out bond strength of mineral trioxide aggregate (MTA) and a new endodontic cement (NEC) as root-end filling materials in root-end cavities prepared by ultrasonic technique (US) or Er,Cr:YSGG laser (L). Eighty single-rooted extracted human teeth were endodontically treated, apicectomised and randomly divided into four following groups (n = 20): US/MTA, US/NEC, L/MTA and L/NEC. In US/MTA and US/NEC groups, rooted cavities were prepared with ultrasonic retrotip and filled with MTA and NEC, respectively. In L/MTA and L/NEC groups, root-end cavities were prepared using Er, Cr:YSGG laser and filled with MTA and NEC, respectively. Each root was cut apically to create a 2 mm-thick root slice for measurement of bond strength using a universal testing machine. Then, all slices were examined to determine the mode of bond failure. Data were analysed using two-way ANOVA. Root-end filling materials showed significantly higher bond strength in root-end cavities prepared using the ultrasonic technique (US/MTA and US/NEC) (P < 0.001). The bond strengths of MTA and NEC did not differ significantly. The failure modes were mainly adhesive for MTA, but cohesive for NEC. In conclusion, bond strengths of MTA and NEC to root-end cavities were comparable and higher in ultrasonically prepared cavities.

Keywords: bond strength, Er, Cr:YSGG laser, MTA, NEC, root-end cavity

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1224 Microstructural Evolution of an Interface Region in a Nickel-Based Superalloy Joint Produced by Direct Energy Deposition

Authors: Matthew Ferguson, Tatyana Konkova, Ioannis Violatos

Abstract:

Microstructure analysis of additively manufactured (AM) materials is an important step in understanding the interrelationship between mechanical properties and materials performance. Literature on the effect of laser-based AM process parameters on the microstructure in the substrate-deposit interface is limited. The interface region, the adjoining area of substrate and deposit, is characterized by the presence of the fusion zone (FZ) and heat-affected zone (HAZ), experiencing rapid thermal gyrations resulting in thermal-induced transformations. Inconel 718 was utilized as work material for both the substrate and deposit. Three blocks of Inconel 718 material were deposited by Direct Energy Deposition (DED) using three different laser powers, 550W, 750W and 950W, respectively. A coupled thermo-mechanical transient approach was utilized to correlate temperature history to the evolution of microstructure. The thermal history of the deposition process was monitored with the thermocouples installed inside the substrate material. The interface region of the blocks was analyzed with Optical Microscopy (OM) and Scanning Electron Microscopy (SEM), including the electron back-scattered diffraction (EBSD) technique. Laser power was found to influence the dissolution of intermetallic precipitated phases in the substrate and grain growth in the interface region. Microstructure and thermal history data were utilized to draw conclusive comparisons between the investigated process parameters.

Keywords: additive manufacturing, direct energy deposition, electron back-scattered diffraction, finite element analysis, inconel 718, microstructure, optical microscopy, scanning electron microscopy, substrate-deposit interface region

Procedia PDF Downloads 183
1223 Additive Weibull Model Using Warranty Claim and Finite Element Analysis Fatigue Analysis

Authors: Kanchan Mondal, Dasharath Koulage, Dattatray Manerikar, Asmita Ghate

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This paper presents an additive reliability model using warranty data and Finite Element Analysis (FEA) data. Warranty data for any product gives insight to its underlying issues. This is often used by Reliability Engineers to build prediction model to forecast failure rate of parts. But there is one major limitation in using warranty data for prediction. Warranty periods constitute only a small fraction of total lifetime of a product, most of the time it covers only the infant mortality and useful life zone of a bathtub curve. Predicting with warranty data alone in these cases is not generally provide results with desired accuracy. Failure rate of a mechanical part is driven by random issues initially and wear-out or usage related issues at later stages of the lifetime. For better predictability of failure rate, one need to explore the failure rate behavior at wear out zone of a bathtub curve. Due to cost and time constraints, it is not always possible to test samples till failure, but FEA-Fatigue analysis can provide the failure rate behavior of a part much beyond warranty period in a quicker time and at lesser cost. In this work, the authors proposed an Additive Weibull Model, which make use of both warranty and FEA fatigue analysis data for predicting failure rates. It involves modeling of two data sets of a part, one with existing warranty claims and other with fatigue life data. Hazard rate base Weibull estimation has been used for the modeling the warranty data whereas S-N curved based Weibull parameter estimation is used for FEA data. Two separate Weibull models’ parameters are estimated and combined to form the proposed Additive Weibull Model for prediction.

Keywords: bathtub curve, fatigue, FEA, reliability, warranty, Weibull

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1222 Effects of Boiling Temperature and Time on Colour, Texture and Sensory Properties of Volutharpa ampullacea perryi Meat

Authors: Xianbao Sun, Jinlong Zhao, Shudong He, Jing Li

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Volutharpa ampullacea perryi is a high-protein marine shellfish. However, few data are available on the effects of boiling temperatures and time on quality of the meat. In this study, colour, texture and sensory characteristics of Volutharpa ampullacea perryi meat during the boiling cooking processes (75-100 °C, 5-60 min) were investigated by colors analysis, texture profile analysis (TPA), scanning electron microscope (SEM) and sensory evaluation. The ratio of cooking loss gradually increased with the increase of temperature and time. The colour of meat became lighter and more yellower from 85 °C to 95 °C in a short time (5-20 min), but it became brown after a 30 min treatment. TPA results showed that the Volutharpa ampullacea perryi meat were more firm and less cohesive after a higher temperature (95-100 °C) treatment even in a short period (5-15 min). Based on the SEM analysis, it was easily found that the myofibrils structure was destroyed at a higher temperature (85-100 °C). Sensory data revealed that the meat cooked at 85-90 °C in 10-20 min showed higher scores in overall acceptance, as well as color, hardness and taste. Based on these results, it could be constructed that Volutharpa ampullacea perryi meat should be heated on a suitable condition (such as 85 °C 15 min or 90 °C 10 min) in the boiling cooking to be ensure a better acceptability.

Keywords: Volutharpa ampullacea perryi meat, boiling cooking, colour, sensory, texture

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1221 Role of Social Capital on Consumer Attitudes, Peer Influence and Behavioral Intentions: A Social Media Perspective

Authors: Qazi Mohammed Ahmed, Osman Sadiq Paracha, Iftikhar Hussain

Abstract:

The study aims to explore the unaddressed relationship between social capital and consumers’ underlying behavioral intentions. The study postulates that this association is mediated by the role of attitudes and peer influence. The research attains evidence from a usable sample of 673 responses. The majority consists of the young and energetic social media users of Pakistan that utilize virtual communities as a way of life. A variance based structural equation modeling has been applied through SmartPLS 3. The results reveal that social capital exerts a statistically supportive association with both attitudes and peer influence. Contrastingly, this predictor variable shows an insignificant linkage with behavioral intentions but this relationship is fully mediated by consumer attitudes and peer influence. The paper enhances marketing literature with respect to an unexplored society of Pakistan. It also provides a lens for the contemporary advertisers, in terms of supporting their social media campaigns with affiliative and cohesive elements. The study also identifies a series of predictor variables that could further be tested with attitudes, subjective norms and behavioral responses.

Keywords: social capital, consumer attitudes, peer influence, behavioral intentions

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1220 Construction of Microbial Fuel Cells from Local Benthic Zones

Authors: Maria Luiza D. Ramiento, Maria Lissette D. Lucas

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Electricity is said to serve as the backbone of modern technology. Considering this, electricity consumption has dynamically grown due to the continuous demand. An alternative producer of energy concerning electricity must therefore be given focus. Microbial fuel cell wholly characterizes a new method of renewable energy recovery: the direct conversion of organic matter to electricity using bacteria. Electricity is produced as fuel or new food is given to the bacteria. The study concentrated in determining the feasibility of electricity production from local benthic zones. Microbial fuel cells were constructed to harvest the possible electricity and to test the presence of electricity producing microorganisms. Soil samples were gathered from Calumpang River, Palawan Mangrove Forest, Rosario River and Batangas Port. Eleven modules were constructed for the different trials of the soil samples. These modules were made of cathode and anode chambers connected by a salt bridge. For 85 days, the harvested voltage was measured daily. No parameter is added for the first 24 days. For the next 61 days, acetic acid was included in the first and second trials of the modules. Each of the trials of the soil samples gave a positive result in electricity production.There were electricity producing microbes in local benthic zones. It is observed that the higher the organic content of the soil sample, the higher the electricity harvested from it. It is recommended to identify the specific species of the electricity-producing microorganism present in the local benthic zone. Complement experiments are encouraged like determining the kind of soil particles to test its effect on the amount electricity that can be harvested. To pursue the development of microbial fuel cells by building a closed circuit in it is also suggested.

Keywords: microbial fuel cell, benthic zone, electricity, reduction-oxidation reaction, bacteria

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1219 Trends of Seasonal and Annual Rainfall in the South-Central Climatic Zone of Bangladesh Using Mann-Kendall Trend Test

Authors: M. T. Islam, S. H. Shakif, R. Hasan, S. H. Kobi

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Investigation of rainfall trends is crucial considering climate change, food security, and the economy of a particular region. This research aims to study seasonal and annual precipitation trends and their abrupt changes over time in the south-central climatic zone of Bangladesh using monthly time series data of 50 years (1970-2019). A trend-free pre-whitening method has been employed to make necessary adjustments for autocorrelations in the rainfall data. Trends in rainfall and their intensity have been observed using the non-parametric Mann-Kendall test and Theil-Sen estimator. Significant changes and fluctuation points in the data series have been detected using the sequential Mann-Kendall test at the 95% confidence limit. The study findings show that most of the rainfall stations in the study area have a decreasing precipitation pattern throughout all seasons. The maximum decline in the rainfall intensity has been found for the Tangail station (-8.24 mm/year) during monsoon. Madaripur and Chandpur stations have shown slight positive trends in post-monsoon rainfall. In terms of annual precipitation, a negative rainfall pattern has been identified in each station, with a maximum decrement (-) of 14.48 mm/year at Chandpur. However, all the trends are statistically non-significant within the 95% confidence interval, and their monotonic association with time ranges from very weak to weak. From the sequential Mann-Kendall test, the year of changing points for annual and seasonal downward precipitation trends occur mostly after the 90s for Dhaka and Barishal stations. For Chandpur, the fluctuation points arrive after the mid-70s in most cases.

Keywords: trend analysis, Mann-Kendall test, Theil-Sen estimator, sequential Mann-Kendall test, rainfall trend

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1218 The Development of Competency with a Training Curriculum via Electronic Media for Condominium Managers

Authors: Chisakan Papapankiad

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The purposes of this research were 1) to study the competency of condominium managers, 2) to create the training curriculum via electronic media for condominium managers, and 3) to evaluate the training curriculum for condominium managers. The research methods included document analysis, interview, questionnaire, and a try-out. A total of 20 experts were selected to collect data by using Delphi technique. The designed curriculum was tried out with 30 condominium managers. The important steps of conducting this research included analyzing and synthesizing, creating interview questions, conducting factor analysis and developing the training curriculum, editing by experts, and trying out with sample groups. The findings revealed that there were five core competencies: leadership, human resources management, management, communication, and self-development. The training curriculum was designed and all the learning materials were put into a CD. The evaluation of the training curriculum was performed by five experts and the training curriculum was found to be cohesive and suitable for use in the real world. Moreover, the findings also revealed three important issues: 1) the competencies of the respondents after the experiment were higher than before the experiment and this had a level of significance of 0.01, 2) the competencies remained with the respondents at least 12 weeks and this also had a level of significance of 0.01, and 3) the overall level of satisfaction from the respondents were 'the highest level'.

Keywords: competency training curriculum, condominium managers, electronic media

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1217 Assessing the Impact of Underground Cavities on Buildings with Stepped Foundations on Sloping Lands

Authors: Masoud Mahdavi

Abstract:

The use of sloping lands is increasing due to the reduction of suitable lands for the construction of buildings. In the design and construction of buildings on sloping lands, the foundation has special loading conditions that require the designer and executor to use the slopped foundation. The creation of underground cavities, including urban and subway tunnels, sewers, urban facilities, etc., inside the ground, causes the behavior of the foundation to be unknown. In the present study, using Abacus software, a 45-degree stepped foundation on the ground is designed. The foundations are placed on the ground in a cohesive (no-hole) manner with circular cavities that show the effect of increasing the cross-sectional area of ​​the underground cavities on the foundation's performance. The Kobe earthquake struck the foundation and ground for two seconds. The underground cavities have a circular cross-sectional area with a radius of 5 m, which is located at a depth of 22.54 m above the ground. The results showed that as the number of underground cavities increased, von Mises stress (in the vertical direction) increased. With the increase in the number of underground cavities, the plastic strain on the ground has increased. Also, with the increase in the number of underground cavities, the change in location and speed in the foundation has increased.

Keywords: stepped foundation, sloping ground, Kobe earthquake, Abaqus software, underground excavations

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1216 Regeneration Study on the Athens City Center: Transformation of the Historical Triangle to “Low Pollution and Restricted Vehicle Traffic Zone”

Authors: Chondrogianni Dimitra, Yorgos J. Stephanedes

Abstract:

The impact of the economic crisis, coupled with the aging of the city's old core, is reflected in central Athens. Public and private users, residents, employees, visitors desire the quality upgrading of abandoned buildings and public spaces through environmental upgrading and sustainable mobility, and promotion of the international metropolitan character of the city. In the study, a strategy for reshaping the character and function of the historic Athenian triangle is proposed, aiming at its economic, environmental, and social sustainable development through feasible, meaningful, and non-landscaping solutions of low cost and high positive impact. Sustainable mobility is the main principle in re-planning the study area and transforming it into a “Low Pollution and Limited Vehicle Traffic Zone” is the main strategy. Τhe proposed measures include the development of pedestrian mobility networks by expanding the pedestrian roads and limited-traffic routes, of bicycle networks based on the approved Metropolitan Bicycle Route of Athens, of public transportation networks with new lines of electric mini-buses, and of new regulations for vehicle mobility in the historic triangle. In addition, complementary actions are proposed regarding the provision of Wi-Fi on fixed track media, development of applications that facilitate combined travel and provide real-time data, integration of micromobility (roller skates, Segway, Hoverboard), and its enhancement as a flexible means of personal mobility, and development of car-sharing, ride-sharing and dynamic carpooling initiatives.

Keywords: regeneration plans, sustainable mobility, environmental upgrading, athens historical triangle

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1215 Human-Elephant Conflict and Mitigation Measures in Buffer Zone of Bardia National Park, Nepal

Authors: Rabin Paudel, Dambar Bahadur Mahato, Prabin Poudel, Bijaya Neupane, Sakar Jha

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Understanding Human-Elephant Conflict (HEC) is very important in countries like Nepal, where solutions to escalating conflicts are urgently required. However, most of the HEC mitigation measures implemented so far have been done on an ad hoc basis without the detailed understanding of nature and extent of the damage. This study aims to assess the current scenario of HEC in regards to crop and property damages by Wild Asian Elephant and people’s perception towards existing mitigating measures and elephant conservation in Buffer zone area of Bardia National Park. The methods used were a questionnaire survey (N= 178), key-informant interview (N= 18) and focal group discussions (N= 6). Descriptive statistics were used to determine the nature and extent of damage and to understand people’s perception towards HEC, its mitigation measures and elephant conservation. Chi-square test was applied to determine the significance of crop and property damages with respect to distance from the park boundary. Out of all types of damage, crop damage was found to be the highest (51%), followed by house damage (31%) and damage to stored grains (18%) with winter being the season with the greatest elephant damage. Among 178 respondents, the majority of them (82%) were positive towards elephant conservation despite the increment in HEC incidents as perceived by 88% of total respondents. Among the mitigation measures present, the most applied was electric fence (91%) followed by barbed wire fence (5%), reinforced concrete cement wall (3%) and gabion wall (1%). Most effective mitigation measures were reinforced concrete cement wall and gabion wall. To combat increasing crop damage, the insurance policy should be initiated. The efficiency of the mitigation measures should be timely monitored, and corrective measures should be applied as per the need.

Keywords: crop and property damage, elephant conflict, Asiatic wild elephant, mitigation measures

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1214 Ni-Based Hardfacing Alloy Reinforced with Fused Eutectic Tungsten Carbide Deposited on Infiltrated WC-W-Ni Substrate by Oxyacetylene Welding

Authors: D. Miroud, H. Mokaddem, M. Tata, N. Foucha

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The body of PDC (polycrystalline diamond compact) drill bit can be manufactured from two different materials, steel and tungsten carbide matrix. Commonly the steel body is produced by machining, thermal spraying a bonding layer and hardfacing of Ni-based matrix reinforced with fused eutectic tungsten carbide (WC/W2C). The matrix body bit is manufactured by infiltrating tungsten carbide particles, with a Copper binary or ternary alloy. By erosion-corrosion mechanisms, the PDC drill bits matrix undergoes severe damage, occurring particularly around the PDC inserts and near injection nozzles. In this study, we investigated the possibility to repair the damaged matrix regions by hardfacing technic. Ni-based hardfacing alloy reinforced with fused eutectic tungsten carbide is deposited on infiltrated WC-W-Ni substrate by oxyacetylene welding (OAW). The microstructure at the hardfacing / matrix interface is characterized by SEM- EDS, XRD and micro hardness Hv0.1. The hardfacing conditions greatly affect the dilution phenomenon and the distribution of carbides at the interface, without formation of transition zone. During OAW welding deposition, interdiffusion of atoms occurs: Cu and Sn diffuse from infiltrated matrix substrate into hardfacing and simultaneously Cr and Si alloy elements from hardfacing diffuse towards the substrate. The dilution zone consists of a nickel-rich phase with a heterogeneous distribution of eutectic spherical (Ni-based hardfacing alloy) and irregular (matrix) WC/W2C carbides and a secondary phase rich in Cr-W-Si. Hardfacing conditions cause the dissolution of banding around both spherical and irregular carbides. The micro-hardness of interface is significantly improved by the presence of secondary phase in the inter-dendritic structure.

Keywords: dilution, dissolution, hardfacing, infiltrated matrix, PDC drill bits

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1213 Intercropping Immature Oil Palm (Elaeisguineensis) with Banana, Ginger and Turmeric in Galle District, Sri Lanka

Authors: S. M. Dissanayake, I. R. Palihakkara , K. G. Premathilaka

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Oil palm (Elaeisguineensis) is the world’s leading vegetable oil-producing plant and is well established as a perennial plantation crop in tropical countries. Oil palm in Sri Lanka has spread over 10,000 hectares in the wet zone of the Island. In immature plantations, land productivity can be increased with some selected intercrops. At the immature stage of the plantations (age up to 3-5 years), there is a large amount of free space available inside the plantations. This study attempts to determine the suitability of different intercrops during the immature phase of the oil palm. A field experiment is being conducted at Thalgaswella estate (WL2a) in Galle district, Sri Lanka. The objectives of the study are to evaluate and recommend a suitable immature oil palm-based intercropping system/s. This experiment was established with randomized complete block design (RCBD) with four treatments, including control in three replicates. Banana, ginger, and turmeric were selected as intercrops. Growth parameters of intercrops (plant height, length, width of D-leaf, and yield of intercrops) and girth, length, and number of leaflets of 17th frond in oil palms were taken at two months intervals. In addition to this, chlorophyll content was also measured in both intercrops and oil palm trees. Soil chemical parameters were measured annually. Results were statistically analyzed with SAS software. Results revealed that intercropped banana, turmeric, and ginger had given yields of 7.61Mt/ha, 4.92Mt/ha, and 4.53Mt/ha, respectively. When comparing these yields with mono-crop, banana, turmeric, and ginger intercrop yields as percentages of 16.9%, 24.6%, and 30.2%, respectively. The results of this study could be used to make appropriate policies to increase the unit land productivity in oil palm plantations in a low country wet zone (WL2a) of Sri Lanka.

Keywords: inter-cropping, oil palm, policies, mono-crop, land productivity

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1212 Natural Enemies of the Fall Armyworm (Spodoptera frugiperda, Smith) and Comparing Neem Aqueous Extracts against Its Larvae in Gurage Zone, Central Ethiopia

Authors: Abera Hailu Degaga, Emana Getu Degaga

Abstract:

Spodoptera frugiperda is an invasive insect pest that infests and feeds various crops, particularly affecting maize yields. However, nature has its own way of maintaining balance, and in this case, natural enemies play a crucial role in regulating the population of S. frugiperda. Locally available and easily prepared botanical sources, bio-pesticides, are also important. The objectives of the study were to investigate the natural enemies of S. frugiperda in the Gurage zone and to compare Neem aqueous extracts against its larvae in central Ethiopia. S. frugiperda larvae and egg masses were collected randomly from smallholder maize farms infested with pests between June and August 2023. Our findings revealed the existence of diverse types of parasitoids, predators, and entomopathogenic fungi associated with S. frugiperda. Notably, we documented three species of parasitoids, namely Exorista xanthaspis and Tachina spp. (Diptera: Tachinidae) and Charops annulipes (Hymenoptera: Ichneumonidae). All three species of parasitoids were recorded from Ethiopia for the first time. The overall parasitism rate was 5.3%, with individual rates ranging from 1.3 to 4%. Additionally, we identified ten species of predator insects from four different orders, including Hemiptera, Dermaptera, Coleoptera, and Mantodea, in the maize farms infested with S. frugiperda. Aqueous extract of Neem seed and leaf powder and green leaf exhibited similar mortality rates of S. frugiperda larvae at 72 hours even though there was a significant difference at 24 and 48 hours of the test. For effective management of S. frugiperda further research is necessary to fully exploit the potential of these natural enemies and additionally to use botanical source pesticides like Azadirachta indica.

Keywords: bio-pesticide, natural enemy, parasitoids, predators, Tachinid flies

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1211 Study on Novel Reburning Process for NOx Reduction by Oscillating Injection of Reburn Fuel

Authors: Changyeop Lee, Sewon Kim, Jongho Lee

Abstract:

Reburning technology has been developed to adopt various commercial combustion systems. Fuel lean reburning is an advanced reburning method to reduce NOx economically without using burnout air, however it is not easy to get high NOx reduction efficiency. In the fuel lean reburning system, the localized fuel rich eddies are used to establish partial fuel rich regions so that the NOx can react with hydrocarbon radical restrictively. In this paper, a new advanced reburning method which supplies reburn fuel with oscillatory motion is introduced to increase NOx reduction rate effectively. To clarify whether forced oscillating injection of reburn fuel can effectively reduce NOx emission, experimental tests were conducted in vertical combustion furnace. Experiments were performed in flames stabilized by a gas burner, which was mounted at the bottom of the furnace. The natural gas is used as both main and reburn fuel and total thermal input is about 40kW. The forced oscillating injection of reburn fuel is realized by electronic solenoid valve, so that fuel rich region and fuel lean region is established alternately. In the fuel rich region, NOx is converted to N2 by reburning reaction, however unburned hydrocarbon and CO is oxidized in fuel lean zone and mixing zone at downstream where slightly fuel lean region is formed by mixing of two regions. This paper reports data on flue gas emissions and temperature distribution in the furnace for a wide range of experimental conditions. All experimental data has been measured at steady state. The NOx reduction rate increases up to 41% by forced oscillating reburn motion. The CO emissions were shown to be kept at very low level. And this paper makes clear that in order to decrease NOx concentration in the exhaust when oscillating reburn fuel injection system is adopted, the control of factors such as frequency and duty ratio is very important.

Keywords: NOx, CO, reburning, pollutant

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1210 Exploration of an Environmentally Friendly Form of City Development Combined with a River: An Example of a Four-Dimensional Analysis Based on the Expansion of the City of Jinan across the Yellow River

Authors: Zhaocheng Shang

Abstract:

In order to study the topic of cities crossing rivers, a Four-Dimensional Analysis Method consisting of timeline, X-axis, Y-axis, and Z-axis is proposed. Policies, plans, and their implications are summarized and researched along with the timeline. The X-axis is the direction which is parallel to the river. The research area was chosen because of its important connection function. It is proposed that more surface water network should be built because of the ecological orientation of the research area. And the analysis of groundwater makes it for sure that the proposal is feasible. After the blue water network is settled, the green landscape network which is surrounded by it could be planned. The direction which is transversal to the river (Y-axis) should run through the transportation axis so that the urban texture could stretch in an ecological way. Therefore, it is suggested that the work of the planning bureau and river bureau should be coordinated. The Z-axis research is on the section view of the river, especially on the Yellow River’s special feature of being a perched river. Based on water control safety demands, river parks could be constructed on the embankment buffer zone, whereas many kinds of ornamental trees could be used to build the buffer zone. City Crossing River is a typical case where we make use of landscaping to build a symbiotic relationship between the urban landscape architecture and the environment. The local environment should be respected in the process of city expansion. The planning order of "Benefit- Flood Control Safety" should be replaced by "Flood Control Safety - Landscape Architecture- People - Benefit".

Keywords: blue-green landscape network, city crossing river, four-dimensional analysis method, planning order

Procedia PDF Downloads 139
1209 Disaster Resilience Analysis of Atlanta Interstate Highway System within the Perimeter

Authors: Mengmeng Liu, J. David Frost

Abstract:

Interstate highway system within the Atlanta Perimeter plays an important role in residents’ daily life. The serious influence of Atlanta I-85 Collapses implies that transportation system in the region lacks a cohesive and comprehensive transportation plan. Therefore, disaster resilience analysis of the transportation system is necessary. Resilience is the system’s capability to persist or to maintain transportation services when exposed to changes or shocks. This paper analyzed the resilience of the whole transportation system within the Perimeter and see how removing interstates within the Perimeter will affect the resilience of the transportation system. The data used in the paper are Atlanta transportation networks and LEHD Origin-Destination Employment Statistics data. First, we calculate the traffic flow on each road section based on LEHD data assuming each trip travel along the shortest travel time paths. Second, we calculate the measure of resilience, which is flow-based connectivity and centrality of the transportation network, and see how they will change if we remove each section of interstates from the current transportation system. Finally, we get the resilience function curve of the interstates and identify the most resilient interstates section. The resilience analysis results show that the framework of calculation resilience is effective and can provide some useful information for the transportation planning and sustainability analysis of the transportation infrastructures.

Keywords: connectivity, interstate highway system, network analysis, resilience analysis

Procedia PDF Downloads 237
1208 Analysis of Magnetic Anomaly Data for Identification Structure in Subsurface of Geothermal Manifestation at Candi Umbul Area, Magelang, Central Java Province, Indonesia

Authors: N. A. Kharisa, I. Wulandari, R. Narendratama, M. I. Faisal, K. Kirana, R. Zipora, I. Arfiansah, I. Suyanto

Abstract:

Acquisition of geophysical survey with magnetic method has been done in manifestation of geothermalat Candi Umbul, Grabag, Magelang, Central Java Province on 10-12 May 2013. This objective research is interpretation to interpret structural geology that control geothermal system in CandiUmbul area. The research has been finished with area size 1,5 km x 2 km and measurement space of 150 m. And each point of line space survey is 150 m using PPM Geometrics model G-856. Data processing was started with IGRF and diurnal variation correction to get total magnetic field anomaly. Then, advance processing was done until reduction to pole, upward continuation, and residual anomaly. That results become next interpretation in qualitative step. It is known that the biggest object position causes low anomaly located in central of area survey that comes from hot spring manifestation and demagnetization zone that indicates the existence of heat source activity. Then, modeling the anomaly map was used for quantitative interpretation step. The result of modeling is rock layers and geological structure model that can inform about the geothermal system. And further information from quantitative interpretations can be interpreted about lithology susceptibility. And lithology susceptibilities are andesiteas heat source has susceptibility value of (k= 0.00014 emu), basaltic as alteration rock (k= 0.0016 emu), volcanic breccia as reservoir rock (k= 0.0026 emu), andesite porfirtic as cap rock (k= 0.004 emu), lava andesite (k= 0.003 emu), and alluvium (k= 0.0007 emu). The hot spring manifestation is controlled by the normal fault which becomes a weak zone, easily passed by hot water which comes from the geothermal reservoir.

Keywords: geological structure, geothermal system, magnetic, susceptibility

Procedia PDF Downloads 371
1207 Effect of UV/Ozone Treatment on the Adhesion Strength of Polymeric Systems

Authors: Marouen Hamdi, Johannes A. Poulis

Abstract:

This study investigates the impact of UV/ozone treatment on the adhesion of ethylene propylene diene methylene (EPDM) rubber, polyvinyl chloride (PVC), and acrylonitrile butadiene styrene (ABS) materials. The experimental tests consist of contact angle measurements, standardized adhesion tests, and spectroscopic and microscopic observations. Also, commonly-used surface free energy models were applied to characterize the wettability of the materials. Preliminary results show that the treatment enhances the wettability of the examined polymers. Also, it considerably improved the adhesion strength of PVC and ABS and shifted their failure modes from adhesive to cohesive, without a significant effect on EPDM. Spectroscopic characterization showed significant oxidation-induced changes in the chemical structures of treated PVC and ABS surfaces. Also, new morphological changes (microcracks, micro-holes, and wrinkles) were observed on these two materials using the SEM. These chemical and morphological changes on treated PVC and ABS promote more reactivity and mechanical interlocking with the adhesive, which explains the improvement in their adhesion strength. After characterizing the adhesion strength of the systems, accelerated ageing tests in controlled environment chambers will be conducted to determine the effect of temperature, moisture, and UV radiation on the performance of the polymeric bonded joints.

Keywords: accelerated tests, adhesion strength, ageing of polymers, UV/ozone treatment

Procedia PDF Downloads 131
1206 Investigating Income Diversification Strategies into Off-Farm Activities Among Rural Households in Ethiopia

Authors: Kibret Berhanu Getinet

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Off-farm income diversification by farm rural households has gained the attention of researchers and policymakers due to the fact that agriculture failed to meet the needs of people in developing countries like Ethiopia. The objective of this study was to investigate income diversification strategies into off-farm activities among rural households in Hawassa Zuria Woreda, Sidama National Regional State, Ethiopia. The study used primary and secondary data sources for the primary data collection questionnaire employed as a data collection instrument. A multistage sampling technique was used to collect data from a total of 197 sample households from four kebeles of the study area. Descriptive statistics, as well as econometrics methods of data analysis, were employed. The descriptive statistics result indicates that the majority of sample rural households (68.53 %) have engaged in off-farm income diversification activities while the remaining 31.47% of households did not participate in the diversification in the study area. The choice of participants among the strategies indicates that 6.60% of respondents participated in off-farm wage employment, 30.46% participated in off-farm self-employment, and about 31.47% of them participated in both off-farm wage employment. The study revealed that the share of off-farm income in total annual earnings of households was about 48.457%, and thus, the off-farm diversification significantly contributes to the rural household income. Moreover, binary and multinomial logistic regression models were employed to identify factors that affect the participation and the choices of the off-farm income diversification strategies, respectively. The binary logit model result indicated that agro-ecological zone, education status of the households, available technical skills of the household, household saving, total livestock owned by the households, access to electricity, road access and being married of household head were significant and positively affected the chance of diversification in off-farm activities while the on-farm income of households is negatively affected the chance of diversification. Similarly, the multinomial logistic regression model estimate revealed that agroecological zone, on-farm income, available technical skills, household savings, and access to electricity are positively related and significantly influenced the household’s choice of employment into off-farm wage employment. The off-farm self-employment diversification choice is significantly influenced by on-farm income, available technical skills, household savings, total livestock owned, and access to electricity. Moreover, the result showed that the factors that affect the choice of farm households to engage in both off-farm wage and self-employment are ecological zone, education status, on-farm income, available technical skills, household own saving, market access, total livestock owned, access to electricity and road access. Thus, due attention should be given to addressing the demographic, socio-economic, and institutional constraints to strengthen off-farm income diversification strategies to improve the income of rural households.

Keywords: off-farm, incoem, diversification, logit model

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1205 Using Google Distance Matrix Application Programming Interface to Reveal and Handle Urban Road Congestion Hot Spots: A Case Study from Budapest

Authors: Peter Baji

Abstract:

In recent years, a growing body of literature emphasizes the increasingly negative impacts of urban road congestion in the everyday life of citizens. Although there are different responses from the public sector to decrease traffic congestion in urban regions, the most effective public intervention is using congestion charges. Because travel is an economic asset, its consumption can be controlled by extra taxes or prices effectively, but this demand-side intervention is often unpopular. Measuring traffic flows with the help of different methods has a long history in transport sciences, but until recently, there was not enough sufficient data for evaluating road traffic flow patterns on the scale of an entire road system of a larger urban area. European cities (e.g., London, Stockholm, Milan), in which congestion charges have already been introduced, designated a particular zone in their downtown for paying, but it protects only the users and inhabitants of the CBD (Central Business District) area. Through the use of Google Maps data as a resource for revealing urban road traffic flow patterns, this paper aims to provide a solution for a fairer and smarter congestion pricing method in cities. The case study area of the research contains three bordering districts of Budapest which are linked by one main road. The first district (5th) is the original downtown that is affected by the congestion charge plans of the city. The second district (13th) lies in the transition zone, and it has recently been transformed into a new CBD containing the biggest office zone in Budapest. The third district (4th) is a mainly residential type of area on the outskirts of the city. The raw data of the research was collected with the help of Google’s Distance Matrix API (Application Programming Interface) which provides future estimated traffic data via travel times between freely fixed coordinate pairs. From the difference of free flow and congested travel time data, the daily congestion patterns and hot spots are detectable in all measured roads within the area. The results suggest that the distribution of congestion peak times and hot spots are uneven in the examined area; however, there are frequently congested areas which lie outside the downtown and their inhabitants also need some protection. The conclusion of this case study is that cities can develop a real-time and place-based congestion charge system that forces car users to avoid frequently congested roads by changing their routes or travel modes. This would be a fairer solution for decreasing the negative environmental effects of the urban road transportation instead of protecting a very limited downtown area.

Keywords: Budapest, congestion charge, distance matrix API, application programming interface, pilot study

Procedia PDF Downloads 179
1204 Studying the Impact of Soil Characteristics in Displacement of Retaining Walls Using Finite Element

Authors: Mojtaba Ahmadabadi, Akbar Masoudi, Morteza Rezai

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In this paper, using the finite element method, the effect of soil and wall characteristics was investigated. Thirty and two different models were studied by different parameters. These studies could calculate displacement at any height of the wall for frictional-cohesive soils. The main purpose of this research is to determine the most effective soil characteristics in reducing the wall displacement. Comparing different models showed that the overall increase in internal friction angle, angle of friction between soil and wall and modulus of elasticity reduce the replacement of the wall. In addition, increase in special weight of soil will increase the wall displacement. Based on results, it can be said that all wall displacements were overturning and in the backfill, soil was bulging. Results show that the highest impact is seen in reducing wall displacement, internal friction angle, and the angle friction between soil and wall. One of the advantages of this study is taking into account all the parameters of the soil and walls replacement distribution in wall and backfill soil. In this paper, using the finite element method and considering all parameters of the soil, we investigated the impact of soil parameter in wall displacement. The aim of this study is to provide the best conditions in reducing the wall displacement and displacement wall and soil distribution.

Keywords: retaining wall, fem, soil and wall interaction, angle of internal friction of the soil, wall displacement

Procedia PDF Downloads 375
1203 The Mineralogy of Shales from the Pilbara and How Chemical Weathering Affects the Intact Strength

Authors: Arturo Maldonado

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In the iron ore mining industry, the intact strength of rock units is defined using the uniaxial compressive strength (UCS). This parameter is very important for the classification of shale materials, allowing the split between rock and cohesive soils based on the magnitude of UCS. For this research, it is assumed that UCS less than or equal to 1 MPa is representative of soils. Several researchers have anticipated that the magnitude of UCS reduces with weathering progression, also since UCS is a directional property, its magnitude depends upon the rock fabric orientation. Thus, the paper presents how the UCS of shales is affected by both weathering grade and bedding orientation. The mineralogy of shales has been defined using Hyper-spectral and chemical assays to define the mineral constituents of shale and other non-shale materials. Geological classification tools have been used to define distinct lithological types, and in this manner, the author uses mineralogical datasets to recognize and isolate shales from other rock types and develop tertiary plots for fresh and weathered shales. The mineralogical classification of shales has reduced the contamination of lithology types and facilitated the study of the physical factors affecting the intact strength of shales, like anisotropic strength due to bedding orientation. The analysis of mineralogical characteristics of shales is perhaps the most important contribution of this paper to other researchers who may wish to explore similar methods.

Keywords: rock mechanics, mineralogy, shales, weathering, anisotropy

Procedia PDF Downloads 29
1202 Production of Vermiwash from Medicinal Plants and Its Potential Use as Fungicide against the Alternaria Alternata (fr.) Keissl. Affecting Cucumber (Cucumis sativus L.) in Guyana

Authors: Abdullah Ansari, Sinika Rambaran, Sirpaul Jaikishun

Abstract:

Vermiwash could be used to enhance plant productivity and resistance to some harmful plant pathogens, as well as provide benefit through the disposal of waste matter. Alternaria rot caused by the fungus Alternaria alternata (Fr.) Keissl., is a common soil-borne pathogen that results in postharvest fruit rot of cucumbers, peppers and other cash crops. The production and distribution of Cucumis sativus L. (cucumber) could be severely affected by Alternaria rot. Fungicides are the traditional treatment however; they are not only expensive but can also cause environmental and health problems. Vermiwash was prepared from various medicinal plants (Ocimum tenuiflorum L. {Tulsi}, Azadirachta indica A. Juss. {neem}, Cymbopogon citratus (DC. ex Nees) Stapf. {lemon grass} and Oryza sativa L. {paddy straw} and applied, in vitro, to A. alternata to investigate their effectiveness as organic alternatives to traditional fungicides. All of the samples of vermiwash inhibited the growth of A. alternata. The inhibitive effects on the fungus appeared most effective when A. indica and O. tenuiflorum were used in the production of the vermiwash. Using the serial dilution method, vermiwash from O. tenuiflorum showed the highest percent of inhibition (93.2%), followed by C. citratus (74.7%), A. indica (68.7%), O. sativa, combination, and combination without worms. Using the sterile disc diffusion method, all of the samples produced zones of inhibition against A. alternata. Vermiwash from A. indica produced a zone of inhibition, averaging 15.3mm, followed by O. tenuiflorum (14.0mm), combination without worms, combination, C. citratus and O. sativa. Nystatin produced a zone of inhibition of 10mm. The results indicate that vermiwash is not simply an organic alternative to more traditional chemical fungicides, but it may in fact be a better and more effective product in treating certain fungal plant infections, particularly A. alternata.

Keywords: vermiwash, earthworms, soil, bacteria, alternaria alternata, antifungal, antibacterial

Procedia PDF Downloads 233
1201 Seismic Inversion for Geothermal Exploration

Authors: E. N. Masri, E. Takács

Abstract:

Amplitude Versus Offset (AVO) and simultaneous model-based impedance inversion techniques have not been utilized for geothermal exploration commonly; however, some recent publications called the attention that they can be very useful in the geothermal investigations. In this study, we present rock physical attributes obtained from 3D pre-stack seismic data and well logs collected in a study area of the NW part of Pannonian Basin where the geothermal reservoir is located in the fractured zones of Triassic basement and it was hit by three productive-injection well pairs. The holes were planned very successfully based on the conventional 3D migrated stack volume prior to this study. Subsequently, the available geophysical-geological datasets provided a great opportunity to test modern inversion procedures in the same area. In this presentation, we provide a summary of the theory and application of the most promising seismic inversion techniques from the viewpoint of geothermal exploration. We demonstrate P- and S-wave impedance, as well as the velocity (Vp and Vs), the density, and the Vp/Vs ratio attribute volumes calculated from the seismic and well-logging data sets. After a detailed discussion, we conclude that P-wave impedance and Vp/Vp ratio are the most helpful parameters for lithology discrimination in the study area. They detect the hot water saturated fracture zone very well thus they can be very useful in mapping the investigated reservoir. Integrated interpretation of all the obtained rock-physical parameters is essential. We are extending the above discussed pre-stack seismic tools by studying the possibilities of Elastic Impedance Inversion (EII) for geothermal exploration. That procedure provides two other useful rock-physical properties, the compressibility and the rigidity (Lamé parameters). Results of those newly created elastic parameters will also be demonstrated in the presentation. Geothermal extraction is of great interest nowadays; and we can adopt several methods have been successfully applied in the hydrocarbon exploration for decades to discover new reservoirs and reduce drilling risk and cost.

Keywords: fractured zone, seismic, well-logging, inversion

Procedia PDF Downloads 111
1200 Petrogenesis of the Neoproterozoic Rocks of Megele Area, Asosa, Western Ethiopia

Authors: Temesgen Oljira, Olugbenga Akindeji Okunlola, Akinade Shadrach Olatunji, Dereje Ayalew, Bekele Ayele Bedada

Abstract:

The Western Ethiopian Shield (WES) is underlain by volcano-sedimentary terranes, gneissic terranes, and ophiolitic rocks intruded by different granitoid bodies. For the past few years, Neoproterozoic rocks of the Megele area in the western part of the WES have been explored. Understanding the geology of the area and assessing the mineralized area's economic potential requires petrological, geochemical, and geological characterization of the Neoproterozoic granitoids and associated metavolcanic rocks. Thus, the geological, geochemical, and petrogenetic features of Neoproterozoic granitoids and associated metavolcanic rocks were elucidated using a combination of field mapping, petrological, and geochemical study. The Megele area is part of a low-grade volcano-sedimentary zone that has been intruded by mafic (dolerite dyke) and granitoid intrusions (granodiorite, diorite, granite gneiss). The granodiorite, associated diorite, and granite gneiss are calc-alkaline, peraluminous to slightly metaluminous, S-type granitoids formed in volcanic arc subduction (VAG) to syn-collisional (syn-COLD) tectonic setting by fractionation of LREE-enriched, HREE-depleted basaltic magma with considerable crustal input. While the metabasalt is sub-alkaline (tholeiitic), metaluminous bodies are generated at the mid-oceanic ridge tectonic setting by partially melting HREE-depleted and LREE-enriched basaltic magma. The reworking of sediment-loaded crustal blocks at depth in a subduction zone resulted in the production of S-type granitoids. This basaltic magma was supplied from an LREE-enriched, HREE-depleted mantle.

Keywords: fractional crystallization, geochemistry, Megele, petrogenesis, s-type granite

Procedia PDF Downloads 109