Search results for: resource recovery from water
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12090

Search results for: resource recovery from water

2490 Corrosive Bacteria Attached to Carbon Steel Used in Oil and Gas Company

Authors: Hadjer Didouh, Mohammed Hadj Melliani, Izzeddine Sameut Bouhaik

Abstract:

Microbiologically influenced corrosion (MIC) is a major cause of pipeline failure in the oil and gas industry, particularly affecting carbon steel, which is widely used for its cost-effectiveness and mechanical properties. This study investigates the adhesion of sulfate-reducing bacteria (SRB) and other corrosive microbial species on API 5L X52 carbon steel in crude oil and injection water environments. Experimental results showed that after 72 hours of exposure, biofilm formed extensively, leading to significant corrosion rates. Weight loss measurements indicated a corrosion rate of 0.39 mm/year, with localized pitting observed at depths reaching 120 μm. Electrochemical impedance spectroscopy (EIS) revealed a drastic decrease in charge transfer resistance, from 1200 Ω/cm² for sterile samples to 240 Ω/cm² in the presence of SRB biofilm. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses confirmed the presence of iron sulfide deposits, indicating active bacterial colonization and biofilm-induced pitting corrosion. This study highlights the severe impact of MIC on pipeline infrastructure, emphasizing the need for efficient microbial control strategies. Furthermore, the results provide a framework for the development of enhanced protective coatings and environmentally friendly biocides to mitigate the economic and environmental risks associated with MIC in oilfield operations in Algeria.

Keywords: MIC, corrosion, bacteria, API 5L X52

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2489 Effect of Lignocellulose-Degrading Bacteria Isolated from Termite Gut on the Nutritive Value of Wheat Straw as Ruminant Feed

Authors: Ayoub Azizi-Shotorkhoft, Tahereh Mohammadabadi, Hosein Motamedi, Morteza Chaji, Hasan Fazaeli

Abstract:

This study was conducted to investigate nutritive value of wheat straw processed with termite gut symbiotic bacteria with lignocellulosic-degrading potential including Bacillus licheniformis, Ochrobactrum intermedium and Microbacterium paludicola in vitro. These bacteria were isolated by culturing termite guts contents in different culture media containing different lignin and lignocellulosic materials that had been prepared from water-extracted sawdust and wheat straw. Results showed that incubating wheat straw with all of three isolated bacteria increased (P<0.05) acid-precipitable polymeric lignin (APPL) compared to control, and highest amount of APPL observed following treatment with B. licheniformis. Highest and lowest (P<0.05) in vitro gas production and ruminal organic matter digestibility were obtained when treating wheat straw with B. licheniformis and control, respectively. However, other fermentation parameters such as b (i.e., gas production from the insoluble fermentable fractions at 144h), c (i.e., rate of gas production during incubation), ruminal dry matter digestibility, metabolizable energy, partitioning factor, pH and ammonia nitrogen concentration were similar between experimental treatments (P>0.05). It is concluded that processing wheat straw with isolated bacteria improved its nutritive value as ruminants feed.

Keywords: termite gut bacteria, wheat straw, nutritive value, ruminant

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2488 An Investigation of Passivation Technology in Stainless Steel Alloy

Authors: Feng-Tsai Weng, Rick Wang, Yan-Cong Liao

Abstract:

Passivation is a kind of surface treatment for material to reinforce the corrosion resistance specially the stainless alloy. Passive film, is to getting more potential compared to their status before passivation. An oxidation film can be formed on the surface of stainless steel, which has a strong corrosion resistance ability after passivation treatment. In this research, a new passivation technology is proposed for a special stainless alloy which contains a 12-14% Chromium. This method includes the A-A-A (alkaline-acid-alkaline) process basically, which was developed by Carpenter that can neutralize trapped acid. Besides, a corrosion resistant coating layer was obtained by immersing the parts in a water bath of mineral oil at high temperature. Salt spray test ASTM B368 was conducted to investigated performance of corrosion resistant of the passivated stainless steel alloy parts. Results show much better corrosion resistant that followed a coating process after A-A-A Passivation process, than only using A-A-A process. The passivation time is with more than 380 hours of salt spray test ASTM B368, which is equal to 3000 hours of Salt spray test ASTM B117. Proposed passivation method of stainless steel can be completed in about 3 hours.

Keywords: passivation, alkaline-acid-alkaline, stainless steel, salt spray test

Procedia PDF Downloads 364
2487 The Role of Formal and Informal Social Support in Predicting the Involvement of Mothers and Fathers of Young Children with Autism Spectrum Disorder

Authors: Adi Sharabi, Dafna Marom-Golan

Abstract:

Parents’ involvement in the care of their children with Autism Spectrum Disorder (ASD) and its beneficial effect on the children’s developmental and educational outcomes is well documented. At the same time, parents of children with ASD tend to experience greater psychological distress than parents of children with other developmental disabilities or with typical development. Positive social support is an important resource used by parents to reduce their psychological distress. The goal of the current research was to examine the contribution of formal and informal social support in explaining mothers’ and fathers’ involvement with their young children with ASD. The sample consisted of 107 parents who live in Israel (61 mothers and 46 fathers) of children aged between 2 and 7, all diagnosed with ASD and attending special kindergartens or special day care for children with ASD. Parental involvement and social support perception were assessed. Initial analysis focused on the relations between involvement, support, and demographic variables. In addition, analysis of variance (ANOVA) was conducted to test differences between mothers and fathers. Two hierarchical multiple regression analyses were performed to examine the predicted factors in the involvement model while controlling for group (mothers/fathers). Results indicate that mothers reported significantly higher levels of parenting involvement than fathers. Mothers reported higher levels of general involvement and all sub-types of involvement. For example, mothers reported that they were more interested in and have higher levels of attendance in their child’s educational program. They were also more collaborative in their child’s educational therapeutic program, and socialized with other parents of children from their child’s kindergarten than fathers. Mothers’ involvement was found to be related to their informal support (non-formal relatives). Findings also reveal significant differences between mothers and fathers on the formal support subscale measure of specializes services. Fathers, more than mothers, reported more specializes services support such as social workers or professional therapists. Separate hierarchical multiple regression analyses revealed a unique gender difference in the factors that explained parental involvement. Specifically, informal support only had a unique positive contribution in explaining mothers’, but not fathers’ involvement. This study highlights the central role of mothers in maintaining constant contact with the educational system and the professionals who help care for their child with ASD. At the same time, this research emphasizes the crucial role of both mothers and fathers in their child's development and well-being at every development stage, particularly in early development. Further, different kinds of social support seem to relate to the different kinds of parental involvement. It is in the best interest of educators and family therapists who work with families with children with ASD to support the cohesiveness of the family and the collaboration of the parents by understanding and respecting the way each member addresses the responsibilities of parenting a child with ASD, and her or his need for different types of social support.

Keywords: parental differences, parental involvement, social support, specialized support services

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2486 Cold Stunned Sea Turtle Diet Analysis In Cape Cod Bay from 2015-2020

Authors: Lucille McWilliams

Abstract:

As water temperatures drop in November, Kemp’s Ridley, Loggerhead, and Green sea turtles cold-stun in Cape Cod Bay. The foraging ecology of these sea turtles remains an understudied area of research. In this study, we aim to assess the diet of these turtles using a multi-tissue stable isotope analysis of cold-stunned kemp’s ridley, loggerhead, and green sea turtles stranded from 2015 to 2020. Stable isotope ratios of carbon and nitrogen were measured in blood, front and rear flipper, liver, muscle, skin, and scute tissue samples. We predict an elevated level of Nitrogen isotope ratios in kemp’s ridley and loggerhead turtles compared to green turtles due to the carnivorous loggerheads and kemp ridleys’ carnivorous diet and the greens herbivorous diet. We anticipate empty stomachs due to starvation while stranded, and a variety of foraging strategies, migration patterns, and trophic positions between these species. Data collected from this study will add to the knowledge of these turtles’ prey species and aid managers in the preservation of these species as a mitigation strategy for these turtles' extinction.

Keywords: sea turtles, kemp's ridleys, greens, loggerheads, cold-stunning, diet analysis, stable isotope analysis, environmental science, marine biology

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2485 Microwave Synthesis, Optical Properties and Surface Area Studies of NiO Nanoparticles

Authors: Ayed S. Al-Shihri, Abul Kalam, Abdullah G. Al-Sehemi, Gaohui Du, Tokeer Ahmad, Ahmad Irfan

Abstract:

We report here the synthesis of nickel oxide (NiO) nanoparticles by microwave-assisted method, using a common precipitating agent followed by calcination in air at 400°C. The effect of the microwave and pH on the crystallite size, morphology, structure, energy band gap and surface area of NiO have been investigated by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV-vis) and BET surface area studies. X-ray diffraction studies showed the formation of monophasic and highly crystalline cubic NiO. TEM analysis led to decrease the average grain size of NiO nanoparticles from 16.5 nm to 14 nm on increasing the amount of NaOH. FTIR studies also confirm the formation of NiO nanoparticles. It was observed that on increasing the volume of NaOH, the optical band gap energy (2.85 eV to 2.95 eV) and specific surface area (33.1 to 39.8 m2/g) increases, however the average particles size decreases (16.5 nm to 14 nm). This method may be extended to large scale synthesis of other metal oxides nanoparticles and the present study could be used for the potential applications in water treatment and many other fields.

Keywords: BET surface area analysis, electron microscopy, optical properties, X-ray techniques

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2484 Implications of Internationalization for Management and Practice in Higher Education

Authors: Naziema Begum Jappie

Abstract:

The internationalization of higher education has become a focal point for academic institutions worldwide, including those in South Africa. This paper explores the multifaceted implications of internationalization on management and practice within the South African higher education landscape. Universities all over the world are increasingly recognizing the challenges of globalization and the pressures towards internationalization. Internationalization in higher education encompasses a range of activities, including academic exchange programs, research collaborations, joint degree programs, and the recruitment of international students and faculty. In South Africa, this process is driven by various factors, including the quest for global competitiveness, the pursuit of academic excellence, and the promotion of cultural diversity. However, while internationalization presents numerous opportunities, it also brings forth significant challenges that require careful consideration by management and practitioners in higher education institutions. Furthermore, the internationalization of higher education in South Africa has significant implications for teaching and learning practices. With an increasingly diverse student body, educators must employ innovative pedagogical approaches that cater to the needs and preferences of a multicultural cohort. This may involve the integration of global perspectives into the curriculum, the use of technology-enhanced learning platforms, and the promotion of intercultural competence among students and faculty. Additionally, the exchange of knowledge and ideas with international partners can enrich research activities and contribute to the advancement of knowledge in various fields. The internationalization of higher education in South Africa has profound implications for management and practice within academic institutions. While it offers opportunities for enhancing academic quality, promoting cultural exchange, and advancing research agendas, it also presents challenges that require strategic planning, resource allocation, and stakeholder engagement. By addressing these challenges proactively and leveraging the opportunities presented by internationalization, South African universities can position themselves as global leaders in higher education while contributing to the socio-economic development of the country and the continent at large. This paper draws together the international experience in South Africa to explore the emerging patterns of strategy and practice in internationalizing Higher Education and will highlight some critical notions of how the concepts of internationalization and globalization in the context of higher education are understood by those who lead universities and what new challenges are being created as universities seek to become more international. Institutions cannot simply have bullet points in the strategic plan for the recruitment of international students; there has to be a complete commitment to a national strategy of inclusivity. This paper will further examine the leadership styles that ensure transformation together with the goals set out for internationalization. Discussions around adding the international relations dimension to the curriculum. Addressing the issues relevant to cross-border delivery of higher education.

Keywords: challenges, higher education, internationalization, strategic focus

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2483 Tourism Potentials of Ikogosi Warm Spring in Nigeria

Authors: A.I. Adeyemo

Abstract:

Ikogosi warm spring results from a complex mechanical and chemical forces that generates internal heat in the rocks forming a warm and cold water at the same geographical location at the same time. From time immemorial, the local community had thought, it to be the work of a deity, and they were worshipping the spring. This complex phenomenon has been a source of tourist attraction to both local and international tourists over the years. 450 copies of a structured questionnaire were given out, and a total of 500 respondents were interviewed. The result showed that ikogosi warm spring impacts the community positively by providing employment to the teeming youths, and it provides income to traders. The result shows that 66% of the respondents confirmed that it increased their income and that transportation business increased more than 73%.the level of enlightenment and socialization increased greatly in the community. However, it also impacted the community negatively as it increased crime rates such as stealing, kidnapping, prostitution, and unwanted pregnancy among the secondary school girls and the other teenagers. Generally, 50% of the respondents reported that tourism in the warm spring results in insecurity in the community. IT also increased environmental problems such as noise and waste pollutions; the continuous movement on the land results in soil compartment leading to erosion, and leaching, which also results in loss of soil fertility. It was concluded that if the potentials of the spring are fully tapped, it will be a good avenue for income generation to the country.

Keywords: community, Ikogosi, revenue, warm spring

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2482 Evaluation of the Role of Bacteria-Derived Flavins as Plant Growth Promoting Molecules

Authors: Nivethika Ajeethan, Lord Abbey, Svetlana Yurge

Abstract:

Riboflavin is a water-soluble vitamin and the direct precursor of the flavin cofactors flavin mononucleotide and flavin adenine dinucleotide. Flavins (FLs) are bioactive molecules that have a beneficial effect on plant growth and development. Sinorhizobium meliloti strain 1021 is an α-proteobacterium that forms agronomically important N₂-fixing symbiosis with Medicago plants and secretes a considerable amount of FLs (FL⁺ strain). This strain was also implicated in plant growth promotion in its association with non-legume host plants. However, the mechanism of this plant growth promotion is not well understood. In this study, we evaluated the growth and development of tomato plants inoculated with S. meliloti 1021 and its mutant (FL⁻ strain) with limited ability to secrete FLs. Our preliminary experiments indicated that inoculation with FL⁺ strain significantly increased seedlings' root and shoot length and surface area compared to those of plants inoculated with FL⁻ strain. For example, the root lengths of 9-day old seedlings inoculated with FL⁺ strain were 35% longer than seedlings inoculated with the mutant. Proteomic approaches combined with the analysis of plant physiological responses such as growth and photosynthetic rate, stomatal conductance, transpiration rate, and chlorophyll content will be used to evaluate the host-plant response to bacteria-derived FLs.

Keywords: flavin, plant growth promotion, riboflavin, Sinorhizobium meliloti

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2481 Hyperelastic Constitutive Modelling of the Male Pelvic System to Understand the Prostate Motion, Deformation and Neoplasms Location with the Influence of MRI-TRUS Fusion Biopsy

Authors: Muhammad Qasim, Dolors Puigjaner, Josep Maria López, Joan Herrero, Carme Olivé, Gerard Fortuny

Abstract:

Computational modeling of the human pelvis using the finite element (FE) method has become extremely important to understand the mechanics of prostate motion and deformation when transrectal ultrasound (TRUS) guided biopsy is performed. The number of reliable and validated hyperelastic constitutive FE models of the male pelvis region is limited, and given models did not precisely describe the anatomical behavior of pelvis organs, mainly of the prostate and its neoplasms location. The motion and deformation of the prostate during TRUS-guided biopsy makes it difficult to know the location of potential lesions in advance. When using this procedure, practitioners can only provide roughly estimations for the lesions locations. Consequently, multiple biopsy samples are required to target one single lesion. In this study, the whole pelvis model (comprised of the rectum, bladder, pelvic muscles, prostate transitional zone (TZ), and peripheral zone (PZ)) is used for the simulation results. An isotropic hyperelastic approach (Signorini model) was used for all the soft tissues except the vesical muscles. The vesical muscles are assumed to have a linear elastic behavior due to the lack of experimental data to determine the constants involved in hyperelastic models. The tissues and organ geometry is taken from the existing literature for 3D meshes. Then the biomechanical parameters were obtained under different testing techniques described in the literature. The acquired parametric values for uniaxial stress/strain data are used in the Signorini model to see the anatomical behavior of the pelvis model. The five mesh nodes in terms of small prostate lesions are selected prior to biopsy and each lesion’s final position is targeted when TRUS probe force of 30 N is applied at the inside rectum wall. Code_Aster open-source software is used for numerical simulations. Moreover, the overall effects of pelvis organ deformation were demonstrated when TRUS–guided biopsy is induced. The deformation of the prostate and neoplasms displacement showed that the appropriate material properties to organs altered the resulting lesion's migration parametrically. As a result, the distance traveled by these lesions ranged between 3.77 and 9.42 mm. The lesion displacement and organ deformation are compared and analyzed with our previous study in which we used linear elastic properties for all pelvic organs. Furthermore, the visual comparison of axial and sagittal slices are also compared, which is taken for Magnetic Resource Imaging (MRI) and TRUS images with our preliminary study.

Keywords: code-aster, magnetic resonance imaging, neoplasms, transrectal ultrasound, TRUS-guided biopsy

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2480 Anti-Graft Instruments and Their Role in Curbing Corruption: Integrity Pact and Its Impact on Indian Procurement

Authors: Jot Prakash Kaur

Abstract:

The paper aims to showcase that with the introduction of anti-graft instruments and willingness of the governments towards their implementation, a significant change can be witnessed in the anti-corruption landscape of any country. Since the past decade anti-graft instruments have been introduced by several international non-governmental organizations with the vision of curbing corruption. Transparency International’s ‘Integrity Pact’ has been one such initiative. Integrity Pact has been described as a tool for preventing corruption in public contracting. Integrity Pact has found its relevance in a developing country like India where public procurement constitutes 25-30 percent of Gross Domestic Product. Corruption in public procurement has been a cause of concern even though India has in place a whole architecture of rules and regulations governing public procurement. Integrity Pact was first adopted by a leading Oil and Gas government company in 2006. Till May 2015, over ninety organizations had adopted Integrity Pact, of which majority of them are central government units. The methodology undertaken to understand impact of Integrity Pact on Public procurement is through analyzing information received from important stakeholders of the instrument. Government, information was sought through Right to Information Act 2005 about the details of adoption of this instrument by various government organizations and departments. Contractor, Company websites and annual reports were used to find out the steps taken towards implementation of Integrity Pact. Civil Society, Transparency International India’s resource materials which include publications and reports on Integrity Pact were also used to understand the impact of Integrity Pact. Some of the findings of the study include organizations adopting Integrity pacts in all kinds of contracts such that 90% of their procurements fall under Integrity Pact. Indian State governments have found merit in Integrity Pact and have adopted it in their procurement contracts. Integrity Pact has been instrumental in creating a brand image of companies. External Monitors, an essential feature of Integrity Pact have emerged as arbitrators for the bidders and are the first line of procurement auditors for the organizations. India has cancelled two defense contracts finding it conflicting with the provisions of Integrity Pact. Some of the clauses of Integrity Pact have been included in the proposed Public Procurement legislation. Integrity Pact has slowly but steadily grown to become an integral part of big ticket procurement in India. Government’s commitment to implement Integrity Pact has changed the way in which public procurement is conducted in India. Public Procurement was a segment infested with corruption but with the adoption of Integrity Pact a number of clean up acts have been performed to make procurement transparent. The paper is divided in five sections. First section elaborates on Integrity Pact. Second section talks about stakeholders of the instrument and the role it plays in its implementation. Third section talks about the efforts taken by the government to implement Integrity Pact in India. Fourth section talks about the role of External Monitor as Arbitrator. The final section puts forth suggestions to strengthen the existing form of Integrity Pact and increase its reach.

Keywords: corruption, integrity pact, procurement, vigilance

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2479 Innovation Potential of Palm Kernel Shells from the Littoral Region in Cameroon

Authors: Marcelle Muriel Domkam Tchunkam, Rolin Feudjio

Abstract:

This work investigates the ultrastructure, physicochemical and thermal properties evaluation of Palm Kernel Shells (PKS). PKS Tenera waste samples were obtained from a palm oil mill in Dizangué Sub-Division, Littoral region of Cameroon, while PKS Dura waste samples were collected from the Institute of Agricultural Research for Development (IRAD) of Mbongo. A sodium hydroxide solution was used to wash the shells. They were then rinsed by demineralised water and dried in an oven at 70 °C during 72 hours. They were then grounded and sieved to obtained powders from 0.04 mm to 0.45 mm in size. Transmission Electron Microscopy (TEM) and Surface Electron Microscopy (SEM) were used to characterized powder samples. Chemical compounds and elemental constituents, as well as thermal performance were evaluated by Van Soest Method, TEM/EDXA and SEM/EDS techniques. Thermal characterization was also performed using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Our results from microstructural analysis revealed that most of the PKS material is made of particles with irregular morphology, mainly amorphous phases of carbon/oxygen with small amounts of Ca, K, and Mg. The DSC data enabled the derivation of the materials’ thermal transition phases and the relevant characteristic temperatures and physical properties. Overall, our data show that PKS have nanopores and show potential in 3D printing and membrane filtration applications.

Keywords: DSC, EDXA, palm kernel shells, SEM, TEM

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2478 Eating Habits of Children Aged 10-15 Years in Reference to Nutrition Status

Authors: M. Hetmańczyk, R. Polaniak, K. Brukało, E. Grochowska-Niedworok

Abstract:

Eating behaviours of people are determined by knowledge gained at different stages of life. Children’s diet is especially important. They have to eat meals regularly. Meals should consist of protein, carbohydrates and fat, and drinking the right amount of water. Mistakes in children’s diets affect their health and may lead to health issues such as diabetes, overweight, obesity or malnutrition. The aim of the study was to assess the eating habits among 10-15-year-old children. To achieve this aim, the study included children aged 10-15 years living in Silesia Province, Poland; the participants consisted of 52.08% girls and 47.92% boys. Authorial questionnaire contains 28 questions about eating habits. The results of 192 students were subjected to analysis. The results show that half of the surveyed students participated in physical activity every day. Most children ate 4-5 meals every day, but the breaks between them were too long (four and more hours). Children generally ate cooked meals. Most children ate first breakfast every day, but only one third of studied children ate a second breakfast daily, while 93.75% ate vegetables at least once a day, 94.79% ate fruit at least once a day, and 79.17% drink a daily glass of milk or more. The study found that the eating behaviours of the surveyed children were unsatisfying. While the children did not participate in physical activity often enough, girls took part slightly more often. Children eat second breakfast not often enough. Younger children (10-12 years old) are doing it more often than the older children (13-15 years old). Gender is not a determinant of the frequency of second breakfast consumption.

Keywords: eating habits, children, diet, nutrition status

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2477 Effect of Nitriding and Shot Peening on Corrosion Behavior and Surface Properties of Austenite Stainless Steel 316L

Authors: Khiaira S. Hassan, Abbas S. Alwan, Muna K. Abbass

Abstract:

This research aims to study the effect of the liquid nitriding and shot peening on the hardness, surface roughness, residual stress, microstructure and corrosion behavior of austenite stainless steel 316 L. Chemical surface heat treatment by liquid nitriding process was carried out at 500 °C for 1 h and followed by shot peening with using ball steel diameter of 1.25 mm in different exposure time of 10 and 20 min. Electrochemical corrosion test was applied in sea water (3.5% NaCl solution) by using potentostat instrument. The results showed that the nitride layer consists of a compound layer (white layer) and diffusion zone immediately below the alloy layer. It has been found that the mechanical treatment (shot peening) has led to the formation of compressive residual stresses in layer surface that increased the hardness of stainless steel surface. All surface treatment (nitriding and shot peening) processes have led to the formation of carbide of CrN in hard surface layer. It was shown that both processes caused an increase in surface hardness and roughness which increases with shot peening time. Also, the corrosion results showed that the liquid nitriding and shot peening processes increase the corrosion rate to values more than that of not treated stainless steel.

Keywords: stainless steel 316L, shot peening, nitriding, corrosion, hardness

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2476 On the Fixed Rainfall Intensity: Effects on Overland Flow Resistance, Shear Velocity and on Soil Erosion

Authors: L. Mouzai, M. Bouhadef

Abstract:

Raindrops and overland flow both are erosive parameters but they do not act by the same way. The overland flow alone tends to shear the soil horizontally and concentrates into rills. In the presence of rain, the soil particles are removed from the soil surface in the form of a uniform sheet layer. In addition to this, raindrops falling on the flow roughen the water and soil surface depending on the flow depth, and retard the velocity, therefore influence shear velocity and Manning’s factor. To investigate this part, agricultural sandy soil, rainfall simulator and a laboratory soil tray of 0.2x1x3 m were the base of this work. Five overland flow depths of 0; 3.28; 4.28; 5.16; 5.60; 5.80 mm were generated under a rainfall intensity of 217.2 mm/h. Sediment concentration control is based on the proportionality of depth/microtopography. The soil loose is directly related to the presence of rain splash on thin sheet flow. The effect of shear velocity on sediment concentration is limited by the value of 5.28 cm/s. In addition to this, the rain splash reduces the soil roughness by breaking the soil crests. The rainfall intensity is the major factor influencing depth and soil erosion. In the presence of rainfall, the shear velocity of the flow is due to two simultaneous effects. The first, which is horizontal, comes from the flow and the second, vertical, is due to the raindrops.

Keywords: flow resistance, laboratory experiments, rainfall simulator, sediment concentration, shear velocity, soil erosion

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2475 Physiological Response of Naturally Regenerated Pinus taeda L. Saplings to Four Levels of Stem Inoculation with Leptographium terebrantis

Authors: John K. Mensah, Mary A. Sword Sayer, Ryan L. Nadel, George Matusick, Zhaofei Fan, Lori G. Eckhardt

Abstract:

Leptographium terebrantis is an opportunistic root pathogen commonly associated with loblolly pine (Pinus taeda L.) stands that are undergoing a loss of vigor in the southeastern US. In order to understand the relationship between L. terebrantis inoculum density and host physiology, an artificial inoculation study was conducted in a five-year-old naturally regenerated loblolly pine stand over a 24 week period in a completely randomized design. L. terebrantis caused sapwood occlusions that increased in severity as inoculum density increased. The occlusions significantly reduced water transport through the stem but did not interfere with fascicle-level stomatal conductance or induce moisture stress in the saplings. The resilience of stomatal conductance among pathogen-infested saplings is attributed to the growth and hydraulic function of new sapwood that developed after artificial inoculation. Results demonstrate that faster-growing families of loblolly pine may be capable of tolerating the vascular root disease when the formation of new sapwood is supported by sustained crown health.

Keywords: hydraulic conductance, inoculum density, Leptographium terebrantis, Pinus taeda, sapwood occlusion

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2474 Geospatial Modeling Framework for Enhancing Urban Roadway Intersection Safety

Authors: Neeti Nayak, Khalid Duri

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Despite the many advances made in transportation planning, the number of injuries and fatalities in the United States which involve motorized vehicles near intersections remain largely unchanged year over year. Data from the National Highway Traffic Safety Administration for 2018 indicates accidents involving motorized vehicles at traffic intersections accounted for 8,245 deaths and 914,811 injuries. Furthermore, collisions involving pedal cyclists killed 861 people (38% at intersections) and injured 46,295 (68% at intersections), while accidents involving pedestrians claimed 6,247 lives (25% at intersections) and injured 71,887 (56% at intersections)- the highest tallies registered in nearly 20 years. Some of the causes attributed to the rising number of accidents relate to increasing populations and the associated changes in land and traffic usage patterns, insufficient visibility conditions, and inadequate applications of traffic controls. Intersections that were initially designed with a particular land use pattern in mind may be rendered obsolete by subsequent developments. Many accidents involving pedestrians are accounted for by locations which should have been designed for safe crosswalks. Conventional solutions for evaluating intersection safety often require costly deployment of engineering surveys and analysis, which limit the capacity of resource-constrained administrations to satisfy their community’s needs for safe roadways adequately, effectively relegating mitigation efforts for high-risk areas to post-incident responses. This paper demonstrates how geospatial technology can identify high-risk locations and evaluate the viability of specific intersection management techniques. GIS is used to simulate relevant real-world conditions- the presence of traffic controls, zoning records, locations of interest for human activity, design speed of roadways, topographic details and immovable structures. The proposed methodology provides a low-cost mechanism for empowering urban planners to reduce the risks of accidents using 2-dimensional data representing multi-modal street networks, parcels, crosswalks and demographic information alongside 3-dimensional models of buildings, elevation, slope and aspect surfaces to evaluate visibility and lighting conditions and estimate probabilities for jaywalking and risks posed by blind or uncontrolled intersections. The proposed tools were developed using sample areas of Southern California, but the model will scale to other cities which conform to similar transportation standards given the availability of relevant GIS data.

Keywords: crosswalks, cyclist safety, geotechnology, GIS, intersection safety, pedestrian safety, roadway safety, transportation planning, urban design

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2473 Controlled Conductivity of Poly (3,4-Ethylenedioxythiophene): Poly (4-Styrene Sulfonate) Composites with Polyester

Authors: Kazui Sasakii, Seira Mormune-Moriya, Hiroaki Tanahashi, Shigeji Kongaya

Abstract:

Poly (3.4-ethylenedioxythiophene) doped with poly (4-styrene sulfonate) (PEDOT: PSS) attracted a great deal of attention because of its unique characteristics of flexibility, optical properties, heat resistance and colloidal dispersion in water. It is well known that when high boiling solvents such as ethylene glycol or dimethyl sulfoxide are added as a secondary dopant to the micellar structure, PEDOT microcrystallizes and becomes highly conductive. In previous study bis(4-hydroxyphenyl) sulfone (BPS) was used as a secondary dopant for PEDOT:PSS and the enhancement of the conductivity was revealed. However, ductility is one of the serious issues which limited the application of PEDOT:PSS/BPS. So far, the composition with polymer binders has been conducted, however, polymer binders decrease the conductivity of the materials. In this study, PEDOT: PSS composites with polyester (PEs) were prepared by a simple aqueous process using PEs emulsion. The structural studies revealed that PEDOT:PSS and PEs were homogeneously distributed in the composites. It was found that the properties of PEDOT:PSS were remarkably enhanced by the incorporation of PEs. According to the tensile test, the ductility of PEDOT:PSS was remarkably improved. Interestingly, the conductivity of PEDOT:PSS/PEs composites was higher than that of neat PEDOT:PSS. For example, the conductivity increased by 8% at PEs content of 25 wt%. Since PEDOT:PSS were homogeneously dispersed on the surface of PEs particles, it was assumed that the conductive pathway was constructed by PEs particles in the nanocomposites. Therefore, a significant increase in conductivity was achieved.

Keywords: polymer composites, conductivity, PEDOT:PSS, polyester

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2472 Photocatalytic Degradation of Toxic Phenols Using Zinc Oxide Doped Prussian Blue Nanocomposite

Authors: Rachna, Uma Shanker

Abstract:

Aromatic phenols, being priority pollutants, are found in various industrial effluents and seeking the attention of environmentalists worldwide, owing to their life-threatening effects. In the present study, the coupling of zinc oxide with Prussian blue was achieved involving co-precipitation synthesis process using Azadirachta indica plant extract. The fabricated nanocatalyst was employed for the sunlight mediated photodegradation of various phenols (Phenol, 3-Aminophenol, and 2,4-Dinitrophenol). Doping of zinc oxide with Prussian blue caused an increase in the surface area to value 80.109 m²g⁻¹ and also enhanced the semiconducting tendency of the nanocomposite with band gap energy 1.101 eV. The experiment was performed at different parameters of phenols concentration, catalyst amount, pH, time, and exposure of sunlight. The obtained results showed a lower elimination of 2,4-DNP (93%) than 3-AP (97%) and phenol (95%) owing to their molecular weight and basicity differences. In comparison to the starting material (zinc oxide and Prussian blue), nanocomposite was more capable in degrading the phenols and lowered the t1/2 value of phenol (4.405 h), 3-AP (4.04 h) and 2,4-DNP (4.68 h) to a greater extent. Effect of different foreign anions was also studied to check nanocomposite’s liability under natural conditions. The extent of charge recombination being the most limiting factor in the photodegradation of pollutants was determined through the photoluminescence. Sunlight active ZnO@FeHCF nanocomposite was proven to exhibit good catalytic ability up to 10 cycles.

Keywords: nanocomposite, phenols, photodegradation, sunlight, water

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2471 Modeling a Sustainable City in the Twenty-First Century: A Case Study of Ibadan Oyo State Nigeria

Authors: K. J. Jegede, O. O. Odekunle

Abstract:

The challenges facing government at all levels in the area of urban development are two folds, first is how to provide basic services for urban dwellers especially the urban poor and second, how to make cities and towns as model of good places for economic development. The key ingredients and catalysts for achieving these goals are strong and virile institutional capacity, urban infrastructure and a supportive urban policy framework. The government at all levels have been upgrading and expanding city infrastructure and services in Ibadan, the state capital to support sustainable economic development of the city, particularly in the areas of electricity, neighbourhood, solid waste management, transport, water supply, education, health facilities and markets developments to discourage street trading. This paper attempts to present Ibadan in the millennium as 'a model of a sustainable city'. A planned development strategy that had sustained the growth of the city from a war camp in the 19th century to a cosmopolitan city in the 21st century with the potential to become a megacity. The presentation examines, among others, the physical structure and population density of Ibadan city, the challenges of economic development, the development of urban infrastructure and services in Ibadan metropolitan area. The paper submitted by mapping out a strategy to achieve sustainable development of Ibadan city.

Keywords: megacity, physical structure, sustainable city, urban infrastructure

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2470 Green Materials for Hot Mixed Asphalt Production

Authors: Salisu Dahiru, Jibrin M. Kaura, Abubakar I. Jumare, Sulaiman M. Mahmood

Abstract:

Reclaimed asphalt, used automobile tires and rice husk, were regarded as waste. These materials could be used in construction of new roads and for roads rehabilitation. Investigation into the production of a Green Hot Mixed Asphalt (GHMA) pavement using Reclaimed Asphalt Pavement (RAP) as partial replacement for coarse aggregate, Crumb Rubber (CR) from waste automobile tires as modifier for bitumen binder and Rice Husk Ash (RHA) as partial replacement of ordinary portland cement (OPC) filler, for roads construction and rehabilitation was presented. 30% Reclaimed asphalt of total aggregate, 15% Crumb Rubber of total binder content, 5% Rice Husk Ash of total mix, and 5.2% Crumb Rubber Modified Bitumen content were recommended for optimum performance. Loss of marshal stability was investigated on mix with the recommended optimum CRMB. The mix revealed good performance with only about 13% loss of stability after 24 hours of immersion in hot water bath, as against about 24% marshal stability lost reported in previous studies for conventional Hot Mixed Asphalt (HMA).

Keywords: rice husk, reclaimed asphalt, filler, crumb rubber, bitumen content green hot mix asphalt

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2469 Microgrid Design Under Optimal Control With Batch Reinforcement Learning

Authors: Valentin Père, Mathieu Milhé, Fabien Baillon, Jean-Louis Dirion

Abstract:

Microgrids offer potential solutions to meet the need for local grid stability and increase isolated networks autonomy with the integration of intermittent renewable energy production and storage facilities. In such a context, sizing production and storage for a given network is a complex task, highly depending on input data such as power load profile and renewable resource availability. This work aims at developing an operating cost computation methodology for different microgrid designs based on the use of deep reinforcement learning (RL) algorithms to tackle the optimal operation problem in stochastic environments. RL is a data-based sequential decision control method based on Markov decision processes that enable the consideration of random variables for control at a chosen time scale. Agents trained via RL constitute a promising class of Energy Management Systems (EMS) for the operation of microgrids with energy storage. Microgrid sizing (or design) is generally performed by minimizing investment costs and operational costs arising from the EMS behavior. The latter might include economic aspects (power purchase, facilities aging), social aspects (load curtailment), and ecological aspects (carbon emissions). Sizing variables are related to major constraints on the optimal operation of the network by the EMS. In this work, an islanded mode microgrid is considered. Renewable generation is done with photovoltaic panels; an electrochemical battery ensures short-term electricity storage. The controllable unit is a hydrogen tank that is used as a long-term storage unit. The proposed approach focus on the transfer of agent learning for the near-optimal operating cost approximation with deep RL for each microgrid size. Like most data-based algorithms, the training step in RL leads to important computer time. The objective of this work is thus to study the potential of Batch-Constrained Q-learning (BCQ) for the optimal sizing of microgrids and especially to reduce the computation time of operating cost estimation in several microgrid configurations. BCQ is an off-line RL algorithm that is known to be data efficient and can learn better policies than on-line RL algorithms on the same buffer. The general idea is to use the learned policy of agents trained in similar environments to constitute a buffer. The latter is used to train BCQ, and thus the agent learning can be performed without update during interaction sampling. A comparison between online RL and the presented method is performed based on the score by environment and on the computation time.

Keywords: batch-constrained reinforcement learning, control, design, optimal

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2468 Remote Sensing and Gis Use in Trends of Urbanization and Regional Planning

Authors: Sawan Kumar Jangid

Abstract:

The paper attempts to study various facets of urbanization and regional planning in the framework of the present conditions and future needs. Urbanization is a dynamic system in which development and changes are prominent features; which implies population growth and changes in the primary, secondary and tertiary sector in the economy. Urban population is increasing day by day due to a natural increase in population and migration from rural areas, and the impact is bound to have in urban areas in terms of infrastructure, environment, water supply and other vital resources. For the organized way of planning and monitoring the implementation of Physical urban and regional plans high-resolution satellite imagery is the potential solution. Now the Remote Sensing data is widely used in urban as well as regional planning, infrastructure planning mainly telecommunication and transport network planning, highway development, accessibility to market area development in terms of catchment and population built-up area density. With Remote Sensing it is possible to identify urban growth, which falls outside the formal planning control. Remote Sensing and GIS technique combined together facilitate the planners, in making a decision, for general public and investors to have relevant data for their use in minimum time. This paper sketches out the Urbanization modal for the future development of Urban and Regional Planning. The paper suggests, a dynamic approach towards regional development strategy.

Keywords: development, dynamic, migration, resolution

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2467 A Case for Strategic Landscape Infrastructure: South Essex Estuary Park

Authors: Alexandra Steed

Abstract:

Alexandra Steed URBAN was commissioned to undertake the South Essex Green and Blue Infrastructure Study (SEGBI) on behalf of the Association of South Essex Local Authorities (ASELA): a partnership of seven neighboring councils within the Thames Estuary. Located on London’s doorstep, the 70,000-hectare region is under extraordinary pressure for regeneration, further development, and economic expansion, yet faces extreme challenges: sea-level rise and inadequate flood defenses, stormwater flooding and threatened infrastructure, loss of internationally important habitats, significant existing community deprivation, and lack of connectivity and access to green space. The brief was to embrace these challenges in the creation of a document that would form a key part of ASELA’s Joint Strategic Framework and feed into local plans and master plans. Thus, helping to tackle climate change, ecological collapse, and social inequity at a regional scale whilst creating a relationship and awareness between urban communities and the surrounding landscapes and nature. The SEGBI project applied a ‘land-based’ methodology, combined with a co-design approach involving numerous stakeholders, to explore how living infrastructure can address these significant issues, reshape future planning and development, and create thriving places for the whole community of life. It comprised three key stages, including Baseline Review; Green and Blue Infrastructure Assessment; and the final Green and Blue Infrastructure Report. The resulting proposals frame an ambitious vision for the delivery of a new regional South Essex Estuary (SEE) Park – 24,000 hectares of protected and connected landscapes. This unified parkland system will drive effective place-shaping and “leveling up” for the most deprived communities while providing large-scale nature recovery and biodiversity net gain. Comprehensive analysis and policy recommendations ensure best practices will be embedded within planning documents and decisions guiding future development. Furthermore, a Natural Capital Account was undertaken as part of the strategy showing the tremendous economic value of the natural assets. This strategy sets a pioneering precedent that demonstrates how the prioritisation of living infrastructure has the capacity to address climate change and ecological collapse, while also supporting sustainable housing, healthier communities, and resilient infrastructures. It was only achievable through a collaborative and cross-boundary approach to strategic planning and growth, with a shared vision of place, and a strong commitment to delivery. With joined-up thinking and a joined-up region, a more impactful plan for South Essex was developed that will lead to numerous environmental, social, and economic benefits across the region, and enhancing the landscape and natural environs on the periphery of one of the largest cities in the world.

Keywords: climate change, green and blue infrastructure, landscape architecture, master planning, regional planning, social equity

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2466 Sediment Delivery from Hillslope Cultivation in Northwest Vietnam

Authors: Vu Dinh Tuan, Truc Xuyen Nguyen Phan, Nguyen Thi Truc Nhi

Abstract:

Cultivating on hillslopes in Northwest Vietnam induced soil erosion that reduce overall soil fertility, capacity of water bodies and drainage ditches or channels, and enhance the risk of flooding, even obstruct traffics and create 'mud flooding or landslide’. This study aimed at assessing the magnitude of erosion under maize monocropping and perennial teak plantation on a rainstorm basic over two years 2010-2011 using double sediment fences installed at convergent point of catchments (slope inclination of 27-74%). Mean annual soil erosion under maize cultivation was 4.39 kg.m⁻², being far greater than that under teak plantation 1.65 kg.m⁻². Intensive tillage in maize monocropping and clearance of land before sowing was most probably the causes induced such effect as no tillage was performed in teak plantation during monitored period. Larger sediment generated across two land use types in year 2010 (4.11 kg.m⁻²) compared to year 2011 (1.87 kg.m⁻²) was attributed to higher amount and intensity of precipitation in the first year (1448 mm) as compared to the latter year (1299 mm). Reducing tillage and establishing good cover for maize monocropping on steep slopes, therefore, are necessary to reduce soil erosion and control sediment delivery to downstream.

Keywords: maize monocropping, teak plantation, tillage, sediment fence, sediment delivery, soil erosion

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2465 Recent Trend in Gluten-Free Bakery Products

Authors: Madhuresh Dwivedi, Navneet Singh Deora, H. N. Mishra

Abstract:

In the context of bakery products, the gluten component of wheat has a crucial role in stabilizing the gas-cell and crumb structures, appearance, mouth feel and maintaining the rheological properties, thus the acceptability of these products. However, because of coeliac disease, some individuals cannot tolerate the protein gliadin present in the gluten fraction of wheat flour. Also termed as gluten-sensitive enteropathy, it is a common chronicle disorder in populations throughout the world with average prevalence of 0.37%. The safest way for celiac sufferers is to stay away from gluten-containing foods such as wheat, rye, barley as well as durum wheat, spelt wheat, and triticale. Thus, in view of the current increasing incidence of gluten intolerant sufferers (due to improved diagnostic procedures), the development of gluten-free cereal-based bakery products suitable for celiac patients represents a challenging and serious task, but also very demanding call for food technologists as well as for the bakers. The use of alternative cereal starches (like rice, soy, maize, potato and so on), gums, hydrocolloids, dietary fibres, alternative protein sources, prebiotics and combinations of them represent the most widespread approach used as replacement to mimic gluten in the manufacture of industrial processable gluten-free bakery products due to their structure-building and water binding properties.

Keywords: gluten-free, coeliac disease, alternative flour, hydrocolloid, crumb structure

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2464 Determinants of Sustainable Supplier Selection: An Exploratory Study of Manufacturing Tunisian’s SMEs

Authors: Ahlem Dhahri, Audrey Becuwe

Abstract:

This study examines the adoption of sustainable purchasing practices among Tunisian SMEs, with a focus on assessing how environmental and social sustainability maturity affects the implementation of sustainable supplier selection (SSS) criteria. Using institutional theory to classify coercive, normative, and mimetic pressures, as well as emerging drivers and barriers, this study explores the institutional factors influencing sustainable purchasing practices and the specific barriers faced by Tunisian SMEs in this area. An exploratory, abductive qualitative research design was adopted for this multiple case study, which involved 19 semi-structured interviews with owners and managers of 17 Tunisian manufacturing SMEs. The Gioia method was used to analyze the data, thus enabling the identification of key themes and relationships directly from the raw data. This approach facilitated a structured interpretation of the institutional factors influencing sustainable purchasing practices, with insights drawn from the participants' perspectives. The study reveals that Tunisian SMEs are at different levels of sustainability maturity, with a significant impact on their procurement practices. SMEs with advanced sustainability maturity integrate both environmental and social criteria into their supplier selection processes, while those with lower maturity levels rely on mostly traditional criteria such as cost, quality, and delivery. Key institutional drivers identified include regulatory pressure, market expectations, and stakeholder influence. Additional emerging drivers—such as certifications and standards, economic incentives, environmental commitment as a core value, and group-wide strategic alignment—also play a critical role in driving sustainable procurement. Conversely, the study reveals significant barriers, including economic constraints, limited awareness, and resource limitations. It also identifies three main categories of emerging barriers: (1) logistical and supply chain constraints, including retailer/intermediary dependency, tariff regulations, and a perceived lack of direct responsibility in B2B supply chains; (2) economic and financial constraints; and (3) operational barriers, such as unilateral environmental responsibility, a product-centric focus and the influence of personal relationships. Providing valuable insights into the role of sustainability maturity in supplier selection, this study is the first to explore sustainable procurement practices in the Tunisian SME context. Integrating an analysis of institutional drivers, including emerging incentives and barriers, provides practical implications for SMEs seeking to improve sustainability in procurement. The results highlight the need for stronger regulatory frameworks and support mechanisms to facilitate the adoption of sustainable practices among SMEs in Tunisia.

Keywords: Tunisian SME, sustainable supplier selection, institutional theory, determinant, qualitative study

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2463 An Examination of Changes on Natural Vegetation due to Charcoal Production Using Multi Temporal Land SAT Data

Authors: T. Garba, Y. Y. Babanyara, M. Isah, A. K. Muktari, R. Y. Abdullahi

Abstract:

The increased in demand of fuel wood for heating, cooking and sometimes bakery has continued to exert appreciable impact on natural vegetation. This study focus on the use of multi-temporal data from land sat TM of 1986, land sat EMT of 1999 and lands sat ETM of 2006 to investigate the changes of Natural Vegetation resulting from charcoal production activities. The three images were classified based on bare soil, built up areas, cultivated land, and natural vegetation, Rock out crop and water bodies. From the classified images Land sat TM of 1986 it shows natural vegetation of the study area to be 308,941.48 hectares equivalent to 50% of the area it then reduces to 278,061.21 which is 42.92% in 1999 it again depreciated to 199,647.81 in 2006 equivalent to 30.83% of the area. Consequently cultivated continue increasing from 259,346.80 hectares (42%) in 1986 to 312,966.27 hectares (48.3%) in 1999 and then to 341.719.92 hectares (52.78%). These show that within the span of 20 years (1986 to 2006) the natural vegetation is depreciated by 119,293.81 hectares. This implies that if the menace is not control the natural might likely be lost in another twenty years. This is because forest cleared for charcoal production is normally converted to farmland. The study therefore concluded that there is the need for alternatives source of domestic energy such as the use of biomass which can easily be accessible and affordable to people. In addition, the study recommended that there should be strong policies enforcement for the protection forest reserved.

Keywords: charcoal, classification, data, images, land use, natural vegetation

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2462 Durability of a Cementitious Matrix Based on Treated Sediments

Authors: Mahfoud Benzerzour, Mouhamadou Amar, Amine Safhi, Nor-Edine Abriak

Abstract:

Significant volumes of sediment are annually dredged in France and all over the world. These materials may, in fact, be used beneficially as supplementary cementitious material. This paper studies the durability of a new cement matrix based on marine dredged sediment of Dunkirk-Harbor (north of France). Several techniques are used to characterize the raw sediment such as physical properties, chemical analyses, and mineralogy. The XRD analysis revealed quartz, calcite, kaolinite as main mineral phases. In order to eliminate organic matter and activate some of those minerals, the sediment is calcined at a temperature of 850°C for 1h. Moreover, four blended mortars were formulated by mixing a portland cement (CEM I 52,5 N) and the calcined sediment as partial cement substitute (0%, 10%, 20% and 30%). Reference mortars, based on the blended cement, were then prepared. This re-use cannot be substantiating and efficient without a durability study. In this purpose, the following tests, mercury porosity, accessible water porosity, chloride permeability, freezing and thawing, external sulfate attack, alkali aggregates reaction, compressive and bending strength tests were conducted on those mortars. The results of most of those tests evidenced the fact that the mortar that contains 10% of the treated sediment is efficient and durable as the reference mortar itself. That would infer that the presence of these calcined sediment improves mortar general behavior.

Keywords: sediment, characterization, calcination, substitution, durability

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2461 Fluorescence in situ Hybridization (FISH) Detection of Bacteria and Archaea in Fecal Samples

Authors: Maria Nejjari, Michel Cloutier, Guylaine Talbot, Martin Lanthier

Abstract:

The fluorescence in situ hybridization (FISH) is a staining technique that allows the identification, detection and quantification of microorganisms without prior cultivation by means of epifluorescence and confocal laser scanning microscopy (CLSM). Oligonucleotide probes have been used to detect bacteria and archaea that colonize the cattle and swine digestive systems. These bacterial strains have been obtained from fecal samples issued from cattle manure and swine slurry. The collection of these samples has been done at 3 different pit’s levels A, B and C with same height. Two collection depth levels have been taken in consideration, one collection level just under the pit’s surface and the second one at the bottom of the pit. Cells were fixed and FISH was performed using oligonucleotides of 15 to 25 nucleotides of length associated with a fluorescent molecule Cy3 or Cy5. The double hybridization using Cy3 probe targeting bacteria (Cy3-EUB338-I) along with a Cy5 probe targeting Archaea (Gy5-ARCH915) gave a better signal. The CLSM images show that there are more bacteria than archaea in swine slurry. However, the choice of fluorescent probes is critical for getting the double hybridization and a unique signature for each microorganism. FISH technique is an easy way to detect pathogens like E. coli O157, Listeria, Salmonella that easily contaminate water streams, agricultural soils and, consequently, food products and endanger human health.

Keywords: archaea, bacteria, detection, FISH, fluorescence

Procedia PDF Downloads 388