Search results for: natural compound
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6560

Search results for: natural compound

4940 Behavioral Responses of Coccinella septempunctata and Diaeretiella rapae toward Semiochemicals and Plant Extract

Authors: Muhammad Tariq, Bushra Siddique, Muhammad Naeem, Asim Gulzar

Abstract:

The chemical ecology of natural enemies can play a pivotal role in any Integrated Pest Management (IPM) program. Different chemical cues help to correspond in the diversity of associations between prey and host plant species. Coccinellaseptempunctata and Diaeretiellarapae have the abilities to explore several chemical cues released by plants under herbivore attack that may enhance their efficiency of foraging. In this study, the behavioral responses of Coccinellaseptempunctata and Diaeretiellarapae were examined under the application of two semiochemicals and a plant extract and their combinations using four-arm olfactometer. The bioassay was consists of a pairwise treatment comparison. Data pertaining to the preference of C. septempunctata and D. rapae after treatment application were recorded and analyzed statistically. The mean number of entries and time spent of Coccinellaseptempunctata and D. rapaewere greater in arms treated with E-β-Farnesene. However, the efficacy of E-β-Farnesene was enhanced when combined with β-pinene. Thus, the mean number of entries and time spent of C. septempunctata and D. rapaewere highest in arms treated with the combination of E-β-Farnesene x β-pinene as compared with other treatments. The current work has demonstrated that the insect-derived semiochemicals may enhance the efficacy of natural enemies when applied in combination.

Keywords: olfectometer, parasitoid, predator, preference

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4939 Extracting Therapeutic Grade Essential Oils from the Lamiaceae Plant Family in the United Arab Emirates (UAE): Highlights on Great Possibilities and Sever Difficulties

Authors: Suzan M. Shahin, Mohammed A. Salem

Abstract:

Essential oils are expensive phytochemicals produced and extracted from specific species belonging to particular families in the plant kingdom. In the United Arab Emirates country (UAE), which is located in the arid region of the world, nine species, from the Lamiaceae family, having the capability to produce therapeutic grade essential oils. These species include; Mentha spicata, Ocimum forskolei, Salvia macrosiphon, Salvia aegyptiaca, Salvia macilenta, Salvia spinosa, Teucrium polium, Teucrium stocksianum, and Zataria multiflora. Although, such potential species are indigenous to the UAE, however, there are almost no studies available to investigate the chemical composition and the quality of the extracted essential oils under the UAE climatological conditions. Therefore, great attention has to be given to such valuable natural resources, through conducting highly supported research projects, tailored to the UAE conditions, and investigating different extraction techniques, including the application of the latest available technologies, such as superficial fluid CO2. This is crucially needed; in order to accomplish the greatest possibilities in the medicinal field, specifically in the discovery of new therapeutic chemotypes, as well as, to achieve the sustainability of this natural resource in the country.

Keywords: essential oils, extraction techniques, Lamiaceae, traditional medicine, United Arab Emirates (UAE)

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4938 Square Concrete Columns under Axial Compression

Authors: Suniti Suparp, Panuwat Joyklad, Qudeer Hussain

Abstract:

This is a well-known fact that the actual latera forces due to natural disasters, for example, earthquakes, floods and storms are difficult to predict accurately. Among these natural disasters, so far, the highest amount of deaths and injuries have been recorded for the case of earthquakes all around the world. Therefore, there is always an urgent need to establish suitable strengthening methods for existing concrete and steel structures. This paper is investigating the structural performance of square concrete columns strengthened using low cost and easily available steel clamps. The salient features of these steel clamps are comparatively low cost, easy availability and ease of installation. To achieve research objectives, a large-scale experimental program was established in which a total number of 12 square concrete columns were constructed and tested under pure axial compression. Three square concrete columns were tested without any steel lamps to serve as a reference specimen. Whereas, remaining concrete columns were externally strengthened using steel clamps. The steel clamps were installed at a different spacing to investigate the best configuration of the steel clamps. The experimental results indicate that steel clamps are very effective in altering the structural performance of the square concrete columns. The square concrete columns externally strengthened using steel clamps demonstrate higher load carrying capacity and ductility as compared with the control specimens.

Keywords: concrete, strength, ductility, pre-stressed, steel, clamps, axial compression, columns, stress and strain

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4937 Vibration of a Beam on an Elastic Foundation Using the Variational Iteration Method

Authors: Desmond Adair, Kairat Ismailov, Martin Jaeger

Abstract:

Modelling of Timoshenko beams on elastic foundations has been widely used in the analysis of buildings, geotechnical problems, and, railway and aerospace structures. For the elastic foundation, the most widely used models are one-parameter mechanical models or two-parameter models to include continuity and cohesion of typical foundations, with the two-parameter usually considered the better of the two. Knowledge of free vibration characteristics of beams on an elastic foundation is considered necessary for optimal design solutions in many engineering applications, and in this work, the efficient and accurate variational iteration method is developed and used to calculate natural frequencies of a Timoshenko beam on a two-parameter foundation. The variational iteration method is a technique capable of dealing with some linear and non-linear problems in an easy and efficient way. The calculations are compared with those using a finite-element method and other analytical solutions, and it is shown that the results are accurate and are obtained efficiently. It is found that the effect of the presence of the two-parameter foundation is to increase the beam’s natural frequencies and this is thought to be because of the shear-layer stiffness, which has an effect on the elastic stiffness. By setting the two-parameter model’s stiffness parameter to zero, it is possible to obtain a one-parameter foundation model, and so, comparison between the two foundation models is also made.

Keywords: Timoshenko beam, variational iteration method, two-parameter elastic foundation model

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4936 Using Geopolymer Technology on Stabilization and Reutilization the Expansion Behavior Slag

Authors: W. H. Lee, T. W. Cheng, K. Y. Lin, S. W. Huang, Y. C. Ding

Abstract:

Basic Oxygen Furnace (BOF) Slag and electric arc furnace (EAF) slag is the by-product of iron making and steel making. Each of slag with produced over 100 million tons annually in Taiwan. The type of slag has great engineering properties, such as, high hardness and density, high compressive strength, low abrasion ratio, and can replace natural aggregate for building materials. However, no matter BOF or EAF slag, both have the expansion problem, due to it contains free lime. The purpose of this study was to stabilize the BOF and EAF slag by using geopolymer technology, hoping can prevent and solve the expansion problem. The experimental results showed that using geopolymer technology can successfully solve and prevent the expansion problem. Their main properties are analyzed with regard to their use as building materials. Autoclave is used to study the volume stability of these specimens. Finally, the compressive strength of geopolymer mortar with BOF/FAF slag can be reached over 21MPa after curing for 28 days. After autoclave testing, the volume expansion does not exceed 0.2%. Even after the autoclave test, the compressive strength can be grown to over 35MPa. In this study have success using these results on ready-mixed concrete plant, and have the same experimental results as laboratory scale. These results gave encouragement that the stabilized and reutilized BOF/EAF slag could be replaced as a feasible natural fine aggregate by using geopolymer technology.

Keywords: BOF slag, EAF slag, autoclave test, geopolymer

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4935 Prandtl Number Influence Analysis on Droplet Migration in Natural Convection Flow Using the Level Set Method

Authors: Isadora Bugarin, Taygoara F. de Oliveira

Abstract:

Multiphase flows have currently been placed as a key solution for technological advances in energy and thermal sciences. The comprehension of droplet motion and behavior on non-isothermal flows is, however, rather limited. The present work consists of an investigation of a 2D droplet migration on natural convection inside a square enclosure with differentially heated walls. The investigation in question concerns the effects on drop motion of imposing different combinations of Prandtl and Rayleigh numbers while defining the drop on distinct initial positions. The finite differences method was used to compute the Navier-Stokes and energy equations for a laminar flow, considering the Boussinesq approximation. Also, a high order level set method was applied to simulate the two-phase flow. A previous analysis developed by the authors had shown that for fixed values of Rayleigh and Prandtl, the variation of the droplet initial position at the beginning of the simulation delivered different patterns of motion, in which for Ra≥10⁴ the droplet presents two very specific behaviors: it can travel through a helical path towards the center or define cyclic circular paths resulting in closed paths when reaching the stationary regime. Now, when varying the Prandtl number for different Rayleigh regimes, it was observed that this particular parameter also affects the migration of the droplet, altering the motion patterns as its value is increased. On higher Prandtl values, the drop performs wider paths with larger amplitudes, traveling closer to the walls and taking longer time periods to finally reach the stationary regime. It is important to highlight that drastic drop behavior changes on the stationary regime were not yet observed, but the path traveled from the begging of the simulation until the stationary regime was significantly altered, resulting in distinct turning over frequencies. The flow’s unsteady Nusselt number is also registered for each case studied, enabling a discussion on the overall effects on heat transfer variations.

Keywords: droplet migration, level set method, multiphase flow, natural convection in enclosure, Prandtl number

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4934 Characterization of a Broad Range Antimicrobial Substance from Pseudozyma aphidis

Authors: Raviv Harris, Maggie Levy

Abstract:

Natural product-based pesticides may serve as an alternative to the traditional synthetic pesticides, which have a potentially damaging effect, both to human health and for the environment. Along with plants, microorganisms are a prospective source of such biological pesticides. A unique and active strain of P. aphidis (designated isolate L12, Israel 2004), an epiphytic and non-pathogenic basidiomycete yeast, was isolated in our lab from strawberry leaves. P. aphidis L12 secretions were found to inhibit broad range of plant pathogens. This work demonstrates that metabolites isolated from the biocontrol agent P. aphidis (isolate L12) can inhibit varied fungal and bacterial phytopathogens. Biologically active metabolites were extracted from P. aphidis biomass, using the organic solvent ethyl acetate. The antimicrobial activity of the extract was demonstrated, both in vitro and in planta. Using disk diffusion assays, the following inhibition zones were obtained: 43cm² for Pseudomonas syringae pv. tomato, 28.5cm² for Xanthomonas campestris pv. vesicatoria, 59cm² for Clavibacter michiganensis subsp. michiganensis, 34cm² for Erwinia amylovora and 34cm² for Agrobacterium tumefaciens. Additionally, strong inhibitory activity of the extract against fungi mycelial growth was established, with IC₅₀ values of 606µg ml⁻¹ for Botrytis cinerea, 221µg ml⁻¹ for Pythium spp., 519µg ml⁻¹ for Rhizoctonia solani, 455µg ml⁻¹ for Sclerotinia sclerotiorum, 2270µg ml⁻¹ for Fusarium oxysporum f. sp. lycopersici, and 2038µg ml⁻¹ for Alternaria alternata. The results of the in planta experiments demonstrated a dose-dependent reduction in disease infection. Significant inhibition of B. cinerea lesions on tomato plants was obtained when a spore suspension of this pathogen was treated with extract concentrations higher than 4.2mg ml⁻¹. Concentration of 7mg ml⁻¹ caused a reduction of over 95% in the lesion size of B. cinerea on tomato plants. The strong antimicrobial activity demonstrated both in vitro and in planta against varied phytopathogens, may indicate that the extracted antimicrobial metabolites have potential to serve as natural pesticides in the field.

Keywords: antimicrobial, B. cinerea, metabolites, natural pesticides, P. aphidis

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4933 The Influences of Green Infrastructure Develop on Urban Renewals for Real Essence and Non-Real Essence Economic Value

Authors: Chao Jen-Chih, Hsu Kuo-Wei

Abstract:

Climate change and natural disasters take effect on urban development. It has been discussed urban renewals can prevent natural disasters. Integrating green infrastructure and urban renewals may have great effect on adapting the impact of climate change. To highlight the economic value of green infrastructure development on urban renewals, some strategies need to be carry on to reduce environmental impact. A number of urban renewals studies has been conducted on right transfer, financial risk, urban renewal policy, and public participation. Little research has been devoted on the subject of the economic value of green infrastructure development on urban renewals. The purpose of this study is to investigate the affecting factors on the economic value of green infrastructure development on urban renewals. This study will present the benefits of green infrastructure development and summarize the critical factors of green infrastructure develop on urban renewals for real essence and non-real essence on economic value from literature. Our results indicate that factors of housing price, land value, floor area incentive, and facilitation of the construction industry affect the outcome of real essence economic value. Factors of enhancement of urban disaster prevention, improvement of urban environment and landscape, crime reduction, climate control, pollution reduction, biological diversity, health impacts, and leisure space affects the outcome of non-real essence economic value.

Keywords: economic value, green infrastructure, urban renewals, urban development

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4932 Solving of Types Mathematical Routine and Non-Routine Problems in Algebra

Authors: Verónica Díaz Quezada

Abstract:

The importance given to the development of the problem solving skill and the requirement to solve problems framed in mathematical or real life contexts, in practice, they are not evidence in relation to the teaching of proportional variations. This qualitative and descriptive study aims to (1) to improve problem solving ability of high school students in Chile, (ii) to elaborate and describe a didactic intervention strategy based on learning situations in proportional variations, focused on solving types of routine problems of various contexts and non-routine problems. For this purpose, participant observation was conducted, test of mathematics problems and an opinion questionnaire to thirty-six high school students. Through the results, the highest academic performance is evidenced in the routine problems of purely mathematical context, realistic, fantasy context, and non-routine problems, except in the routine problems of real context and compound proportionality problems. The results highlight the need to consider in the curriculum different types of problems in the teaching of mathematics that relate the discipline to everyday life situations

Keywords: algebra, high school, proportion variations, nonroutine problem solving, routine problem solving

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4931 Biological Activity of Hibiscus sabdariffa Extract

Authors: Chanasit Chaocharoenphat

Abstract:

Hibiscus sabdariffa is a herbal plant that is commonly used for home remedies in Thailand. This study aims to determine the antioxidant activity of polyphenols, as oxidative stress plays a vital role in the development of cancer, and H. sabdariffa was used in this study. The total flavonoids content was determined using the aluminium chloride colourimetric method and expressed as quercetin equivalents (QE)/g and the antioxidant capacity of the flavonoids using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity assays. The IC50 values of H. sabdariffa extract were 167.14 μg/mL ± 0.843 and 77.59 μg/mL ± 0.798, respectively. In the DPPH assay, vitamin C was used as a positive control, whereas Trolox was used as a positive control in the ABTS assay. To summarise, H. sabdariffa extract contains a high concentration of total flavonoids and exhibits potent antioxidant activity. However, additional antioxidant activity assays such as superoxide dismutase (SOD), reactive oxygen species (ROS), and reactive nitrogen species (RNS) scavenging assays and in vitro antioxidant experiments should be carried out to investigate the molecular mechanism of the compound.

Keywords: ABTS assay, antioxidant activity, Gracilaria fisheri, DPPH assays, total flavonoid content

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4930 A Real Time Development Study for Automated Centralized Remote Monitoring System at Royal Belum Forest

Authors: Amri Yusoff, Shahrizuan Shafiril, Ashardi Abas, Norma Che Yusoff

Abstract:

Nowadays, illegal logging has been causing much effect to our forest. Some of it causes a flash flood, avalanche, global warming, and etc. This comprehensibly makes us wonder why, what, and who has made it happened. Often, it already has been too late after we have known the cause of it. Even the Malaysian Royal Belum forest has not been spared from land clearing or illegal activity by the natives although this area has been gazetted as a protected area preserved for future generations. Furthermore, because of its sizeable and wide area, these illegal activities are difficult to monitor and to maintain. A critical action must be called upon to prevent all of these unhealthy activities from recurrence. Therefore, a remote monitoring device must be developed in order to capture critical real-time data such as temperature, humidity, gaseous, fire, and rain detection which indicates the current and preserved natural state and habitat in the forest. Besides, this device location can be detected via GPS by showing the latitudes and longitudes of its current location and then to be transmitted by SMS via GSM system. All of its readings will be sent in real-time for data management and analysis. This result will be benefited to the monitoring bodies or relevant authority in keeping the forest in the natural habitat. Furthermore, this research is to gather a unified data and then will be analysed for its comparison with an existing method.

Keywords: remote monitoring system, forest data, GSM, GPS, wireless sensor

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4929 Mechanical Behavior of Hybrid Hemp/Jute Fibers Reinforced Polymer Composites at Liquid Nitrogen Temperature

Authors: B. Vinod, L. Jsudev

Abstract:

Natural fibers as reinforcement in polymer matrix material is gaining lot of attention in recent years, as they are light in weight, less in cost, and ecologically advanced surrogate material to glass and carbon fibers in composites. Natural fibers like jute, sisal, coir, hemp, banana etc. have attracted substantial importance as a potential structural material because of its attractive features along with its good mechanical properties. Cryogenic applications of natural fiber reinforced polymer composites like cryogenic wind tunnels, cryogenic transport vessels, support structures in space shuttles and rockets are gaining importance. In these unique cryogenic applications, the requirements of polymer composites are extremely severe and complicated. These materials need to possess good mechanical and physical properties at cryogenic temperatures such as liquid helium (4.2 K), liquid hydrogen (20 K), liquid nitrogen (77 K), and liquid oxygen (90 K) temperatures, etc., to meet the high requirements by the cryogenic engineering applications. The objective of this work is to investigate the mechanical behavior of hybrid hemp/jute fibers reinforced epoxy composite material at liquid nitrogen temperature. Hemp and Jute fibers are used as reinforcement material as they have high specific strength, stiffness and good adhering property and has the potential to replace the synthetic fibers. Hybrid hemp/jute fibers reinforced polymer composite is prepared by hand lay-up method and test specimens are cut according to ASTM standards. These test specimens are dipped in liquid nitrogen for different time durations. The tensile properties, flexural properties and impact strength of the specimen are tested immediately after the specimens are removed from liquid nitrogen container. The experimental results indicate that the cryogenic treatment of the polymer composite has a significant effect on the mechanical properties of this material. The tensile properties and flexural properties of the hybrid hemp/jute fibers epoxy composite at liquid nitrogen temperature is higher than at room temperature. The impact strength of the material decreased after subjecting it to liquid nitrogen temperature.

Keywords: liquid nitrogen temperature, polymer composite, tensile properties, flexural properties

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4928 Examination of the Reasons for the Formation of Red Oil in Spent Caustic from Olefin Plant

Authors: Mehdi Seifollahi, Ashkan Forootan, Sajjad Bahrami Reyhan

Abstract:

Due to the complexity of olefinic plants, various environmental pollutants exist such as NOx, CO2, Tar Water, and most importantly Spent Caustic. In this paper, instead of investigating ways of treating this pollutant, we evaluated the production in relation to plant’s variable items. We primarily discussed the factors affecting the quality of the output spent caustic such as impurities in the feed of olefin plant, the amount of injected dimethyl disulfide (DMDS) in furnaces, variation in feed composition, differences among gas temperatures and the concentration of caustic solution at the bottom of the tower. The results of the laboratory proved that in the formation of Red Oil, 1,3butadiene and acetaldehyde followed free radical and aldol condensation mechanism respectively. By increasing the injection rate of DMDS, Mercaptide amount increases in the effluent. In addition, pyrolysis gasoline accumulation is directly related to caustic concentration in the tower. Increasing naphtenes in the liquid feed augments the amount of 1,3butadiene, as one of the sources of Red Oil formation. By increasing the oxygenated compound in the feed, the rate of acetaldehyde formation, as the main source of Red Oil formation, increases.

Keywords: olefin, spent caustic, red oil, caustic wash tower

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4927 Quantitative Phase Imaging System Based on a Three-Lens Common-Path Interferometer

Authors: Alexander Machikhin, Olga Polschikova, Vitold Pozhar, Alina Ramazanova

Abstract:

White-light quantitative phase imaging is an effective technique for achieving sub-nanometer phase sensitivity. Highly stable interferometers based on common-path geometry have been developed in recent years to solve this task. Some of these methods also apply multispectral approach. The purpose of this research is to suggest a simple and effective interferometer for such systems. We developed a three-lens common-path interferometer, which can be used for quantitative phase imaging with or without multispectral modality. The lens system consists of two components, the first one of which is a compound lens, consisting of two lenses. A pinhole is placed between the components. The lens-in-lens approach enables effective light transmission and high stability of the interferometer. The multispectrality is easily implemented by placing a tunable filter in front of the interferometer. In our work, we used an acousto-optical tunable filter. Some design considerations are discussed and multispectral quantitative phase retrieval is demonstrated.

Keywords: acousto-optical tunable filter, common-path interferometry, digital holography, multispectral quantitative phase imaging

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4926 Hybrid Solutions in Physicochemical Processes for the Removal of Turbidity in Andean Reservoirs

Authors: María Cárdenas Gaudry, Gonzalo Ramces Fano Miranda

Abstract:

Sediment removal is very important in the purification of water, not only for reasons of visual perception but also because of its association with odor and taste problems. The Cuchoquesera reservoir, which is in the Andean region of Ayacucho (Peru) at an altitude of 3,740 meters above sea level, visually presents suspended particles and organic impurities indicating that it contains water of dubious quality to deduce that it is suitable for direct consumption of human beings. In order to quantitatively know the degree of impurities, water quality monitoring was carried out from February to August 2018, in which four sampling stations were established in the reservoir. The selected measured parameters were electrical conductivity, total dissolved solids, pH, color, turbidity, and sludge volume. The indicators of the studied parameters exceed the permissible limits except for electrical conductivity (190 μS/cm) and total dissolved solids (255 mg/L). In this investigation, the best combination and the optimal doses of reagents were determined that allowed the removal of sediments from the waters of the Cuchoquesera reservoir, through the physicochemical process of coagulation-flocculation. In order to improve this process during the rainy season, six combinations of reagents were evaluated, made up of three coagulants (ferric chloride, ferrous sulfate, and aluminum sulfate) and two natural flocculants: prickly pear powder (Opuntia ficus-indica) and tara gum (Caesalpinia spinoza). For each combination of reagents, jar tests were developed following the central composite experimental design (CCED), where the design factors were the doses of coagulant and flocculant and the initial turbidity. The results of the jar tests were adjusted to mathematical models, obtaining that to treat the water from the Cuchoquesera reservoir, with a turbidity of 150 UTN and a color of 137 U Pt-Co, 27.9 mg/L of the coagulant aluminum sulfate with 3 mg/L of the natural tara gum flocculant to produce a purified water quality of 1.7 UTN of turbidity and 3.2 U Pt-Co of apparent color. The estimated cost of the dose of coagulant and flocculant found was 0.22 USD/m³. This is how “grey-green” technologies can be used as a combination in nature-based solutions in water treatment, in this case, to achieve potability, making it more sustainable, especially economically, if green technology is available at the site of application of the nature-based hybrid solution. This research is a demonstration of the compatibility of natural coagulants/flocculants with other treatment technologies in the integrated/hybrid treatment process, such as the possibility of hybridizing natural coagulants with other types of coagulants.

Keywords: prickly pear powder, tara gum, nature-based solutions, aluminum sulfate, jar test, turbidity, coagulation, flocculation

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4925 The Mineral and Petroleum Sectors of Papua New Guinea: An Overview

Authors: James Wapyer, Simon A. Kawagle

Abstract:

The current downturn in the metal and oil prices has significantly affected the mineral and petroleum sectors of Papua New Guinea. The sectors have not grown substantially in the last three years compared to previous years. Resources of several projects have not been proved up as well as feasibility studies not undertaken on advanced projects. In the 2012-2015 periods, however, development licences for four projects have been granted - the Solwara-1 project in the Manus Basin, the Woodlark project, the Crater Mountains project and the Stanley gas-condensate project. There has been some progress on three advanced projects – Frieda River copper-gold porphyry, Mount Kare gold, and the Wafi-Golpu projects. The oilfields are small by world standard but have been high rates of production. The developments of liquefied natural gas projects are progressing well and the first LNG project with ExxonMobil and partners shipped its first cargo in May 2014, the second with Total and partners involving Elk-Antelope gas-condensate fields is in its development stage, and the third with Horizon Oil and partners involving gas fields in the western Papuan basin is in the planning stage. Significantly, in the years 2012-2015, the country has exported liquefied natural gas, nickel, cobalt and chromium, and has granted exploration licences for iron-sands and coal measures for the first time.

Keywords: exploration, mineral, Papua New Guinea, petroleum

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4924 Microbial Corrosion on Oil and Gas Facilities: A Case Study of Oil and Gas Facilities in the Niger-Delta

Authors: Frederick Otite Ighovojah

Abstract:

Corrosion in the oil and gas industries is one of the most common causes of failure. Such failure includes leaks in above-ground storage tanks (AGST). The involvement of microorganisms in the corrosion process in AGST systems is often ignored, and this outlines the need to investigate the effect of microbial corrosion in oil and gas facilities. This study's methodology comprised gathering generated water samples from a nearby AGST oil facility that was operating, which were then equally divided into two batch reactors, 1 and 2. Each batch reactor was filled with five prepared X60 coupons using sterilized forceps. To provide nutrients for the microorganisms in batch reactor 1 during the test period, 2g of NPK 15- 15-15 fertilizer was added on a weekly basis. To kill the microorganisms and significantly lower their concentration in the generated water, 5ml of dissolved ozone (a biocide) with a 0.5ppm concentration was added to batch reactor 2. The weight loss measurement (WLM) was used to evaluate for corrosion. Coupons were removed from each batch reactor, and weight loss was measured at every interval of 336 hrs for 2016 hrs. The overall results obtained indicated that coupons from the batch 1 reactor showed a higher corrosion rate and higher mass loss, and this was due to the metabolic production of an aggressive compound in the medium.

Keywords: AGST, microbial corrosion, reactor, X60 steel

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4923 Cytotoxic Metabolites from Tagetes minuta L. Growing in Saudi Arabia

Authors: Ali A. A. Alqarni, Gamal A. Mohamed, Hossam M. Abdallah, Sabrin R. M. Ibrahim

Abstract:

Phytochemical investigation of the methanolic extract of aerial parts of Tagetes minuta L. (Family: Asteraceae) using different chromatographic techniques led to the isolation of five compounds; ecliptal (1), scopoletin (2), P-hydroxy benzoic acid (3), patuletin (4), and patuletin-7-O-β-D-glucopyranoside (5) (Figure 1). Their structures were established based on physical, chemical, and spectral data [Ultraviolet (UV), Proton ¹H, Carbon thirteen ¹³C, and Heteronuclear Multiple Bond Correlation (HMBC) NMR], as well as Electrospray Ionization Mass Spectroscopy (ESIMS) and comparison with literature data. Their cytotoxic activity was assessed towards human liver hepatocellular carcinoma (HepG2), human breast cancer (MCF-7), and human colon cancer (HCT116) cancer cell lines using sulphorhodamine B (SRB) assay. It is noteworthy that compound 1 demonstrated a significant cytotoxic potential towards HepG2, MCF7, and HCT116 cells with IC₅₀s ranging from 2.74 to 7.01 μM, compared to doxorubicin (IC₅₀ 0.18, 0.60, and 0.20 μM, respectively), whereas compounds 2, 4, and 5 showed moderate cytotoxic potential with IC50s ranging from 11.71 to 35.64 μM. However, 3 was inactive up to a concentration of 100 μM towards the three tested cancer cell lines.

Keywords: Asteraceae, cytotoxicity, metabolites, Tagetes minuta

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4922 Comparison of Illuminance Levels in Old Omani and Portuguese Forts in Oman

Authors: Maatouk Khoukhi

Abstract:

Nowadays the reduction of the energy consumed by buildings to achieve mainly the thermal comfort for the occupants represent the main concern for architects and building designers. The common and traditional solution to achieve this target is the design of a highly insulated envelope and reduce the opening and the transparent elements such windows. However, this will lead to the artificial lighting system to consume more energy to compensate the lack of natural lighting coming through the glazed parts of the building envelope. Therefore, a good balance between sufficient daylight and control thermal heat through the building envelope should be considered for energy saving purpose. To achieve a better indoor environment the windows size and spacing including the interior finishing and the location of the partition must be assessed accurately. Daylighting is the controlled admission of natural light into space through windows and transparent elements of the building envelope which helps create a visually stimulating and productive environment for building occupants. The main concern is not to provide enough daylight to an occupied space, but how to achieve this without any undesirable side effect. Indeed, the glare is a major problem in glazed façade buildings, and this could be reduced by using tinted windows. The main target of this research is to investigate the daylight adequacy of functional needs in old Omani Forts and how they have been designed and built to avoid glare and overheating with the appropriate window-to-floor ratio. Because more windows do not automatically result in more daylighting but that is natural light has been controlled and distributed properly throughout the space. Spaces from different Omani and Portuguese Forts under the same climate conditions are considered in order to compare the daylight illuminance levels and examine the similarities and differences in visual attributes between them. The result of this study indicates that lighting preference is not universal and people from different geographical locations are adapted to certain illuminance levels. Therefore, the standards could not be generalized for the entire world. This would be useful to practitioners who are designing to effectively address the diversity of user’s lighting levels preferences in our globally connected society.

Keywords: day lighting, energy, forts, thermal comfort

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4921 Effect of Red Cabbage Antioxidant Extracts on Lipid Oxidation of Fresh Tilapia

Authors: Ayse Demirbas, Bruce A. Welt, Yavuz Yagiz

Abstract:

Oxidation of polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish causes loss of product quality. Oxidative rancidity causes loss of nutritional value and undesirable color changes. Therefore, powerful antioxidant extracts may provide a relatively low cost and natural means to reduce oxidation, resulting in longer, higher quality and higher value shelf life of foods. In this study, we measured effects of red cabbage antioxidant on lipid oxidation in fresh tilapia filets using thiobarbituric acid reactive substances (TBARS) assay, peroxide value (PV) and color assesment analysis. Extraction of red cabbage was performed using an efficient microwave method. Fresh tilapia filets were dipped in or sprayed with solutions containing different concentrations of extract. Samples were stored for up to 9 days at 4°C and analyzed every other day for color and lipid oxidation. Results showed that treated samples had lower oxidation than controls. Lipid peroxide values on treated samples showed benefits through day-7. Only slight differences were observed between spraying and dipping methods. This work shows that red cabbage antioxidant extracts may represent an inexpensive and all natural method for reducing oxidative spoilage of fresh fish.

Keywords: antioxidant, shelf life, fish, red cabbage, lipid oxidation

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4920 Short Answer Grading Using Multi-Context Features

Authors: S. Sharan Sundar, Nithish B. Moudhgalya, Nidhi Bhandari, Vineeth Vijayaraghavan

Abstract:

Automatic Short Answer Grading is one of the prime applications of artificial intelligence in education. Several approaches involving the utilization of selective handcrafted features, graphical matching techniques, concept identification and mapping, complex deep frameworks, sentence embeddings, etc. have been explored over the years. However, keeping in mind the real-world application of the task, these solutions present a slight overhead in terms of computations and resources in achieving high performances. In this work, a simple and effective solution making use of elemental features based on statistical, linguistic properties, and word-based similarity measures in conjunction with tree-based classifiers and regressors is proposed. The results for classification tasks show improvements ranging from 1%-30%, while the regression task shows a stark improvement of 35%. The authors attribute these improvements to the addition of multiple similarity scores to provide ensemble of scoring criteria to the models. The authors also believe the work could reinstate that classical natural language processing techniques and simple machine learning models can be used to achieve high results for short answer grading.

Keywords: artificial intelligence, intelligent systems, natural language processing, text mining

Procedia PDF Downloads 129
4919 Enhanced Methane Production from Waste Paper through Anaerobic Co-Digestion with Macroalgae

Authors: Cristina Rodriguez, Abed Alaswad, Zaki El-Hassan, Abdul G. Olabi

Abstract:

This study investigates the effect on methane production from the waste paper when co-digested with macroalgal biomass as a source of nitrogen. Both feedstocks were previously mechanically pretreated in order to reduce their particle size. Methane potential assays were carried out at laboratory scale in batch mode for 28 days. The study was planned according to two factors: the feedstock to inoculum (F/I) ratio and the waste paper to macroalgae (WP/MA) ratio. The F/I ratios checked were 0.2, 0.3 and 0.4 and the WP/MA ratios were 0:100, 25:75, 50:50, 75:25 and 100:0. The highest methane yield (608 ml/g of volatile solids (VS)) was achieved at an F/I ratio of 0.2 and a WP/MA ratio of 50:50. The methane yield at a ratio WP/MA of 50:50 is higher than for single compound, while for ratios WP/MA of 25:75 and 75:25 the methane yield decreases compared to biomass mono-digestion. This behavior is observed for the three levels of F/I ratio being more noticeable at F/I ratio of 0.3. A synergistic effect was found for the WP/MA ratio of 50:50 and all F/I ratios and for WP/MA=50:50 and F/I=0.2. A maximum increase of methane yield of 49.58% was found for a co-digestion ratio of 50:50 and an F/I ratio of 0.4. It was concluded that methane production from waste paper improves significantly when co-digested with macroalgae biomass. The methane yields from co-digestion were also found higher that from macroalgae mono-digestion.

Keywords: anaerobic co-digestion, biogas, macroalgae, waste paper

Procedia PDF Downloads 361
4918 Investigating the Correlation Between Customer Satisfaction Components and Reaching Competitive Advantage, Using SEM Approach

Authors: Samaneh Pouyanfar, Michael Oliff

Abstract:

Nowadays, customer satisfaction and discovering the superior services, are counted as vital issues in most manufacturing and services companies. In these terms, gaining the competitive advantage by a business depends on products and services which are able to cause the customer satisfaction. Given the importance of this subject, this paper tries to investigate the correlation between components of customer satisfaction and gaining the competitive advantage by the business. For this purpose, after reviewing the research literature and doing deep interviews with authors and active people in the industry, based on the variables affecting the customer satisfaction and determinant components of business competitive advantage, research questionnaire was prepared. In sum, 96 executives of PARS-KHAZAR Company were asked in a survey. The results of P.L.S. Test for the research structure analysis showed that the measuring tools in terms of technical features, like convergent and divergent validity and compound reliability were very appropriate. Moreover the results showed that, the structure of products and factors related to foundation, has affected the competitive advantage performance positively and significantly; but the influence of structure of services and business environment on competitive advantage was not confirmed.

Keywords: customer satisfaction, competitive advantage, products, foundation, home appliances

Procedia PDF Downloads 271
4917 Behaviour of Hollow Tubes Filled with Sand Slag Concrete

Authors: Meriem Senani, Noureedine Ferhoune

Abstract:

This paper presents the axial bearing capacity of thin welded rectangular steel stubs filled with concrete sand. A series of tests was conducted to study the behavior of short composite columns under axial compressive load, the cross section dimensions were: 100x70x2 mm. A total of 16 stubs have been tested, as follows: 4 filled with ordinary concrete appointed by BO columns, 6 filled with concrete witch natural sand was completely substitute a crystallized sand slag designated in this paper by BSI, and 6 others were tucked in concrete whose natural sand was partially replace by a crystallized sand slag called by BSII. The main objectives of these tests were to clarify the steel specimen's performance filled by concrete sand compared to those filled with ordinary concrete. The main parameters studied are: The height of the specimen (300mm-500mm), eccentricity of load and type of filling concrete. Based on test results obtained, it is confirmed that the length of the tubes, has a considerable effect on the bearing capacity and the failure mode. In all test tubes, fracture occurred by the convex warping of the largest, followed by the smallest due to the outward thrust of the concrete, it was observed that the sand concrete improves the bearing capacity of tubes compounds compared to those filled with ordinary concrete.

Keywords: concrete sand, crystallized slag, failure mode, buckling

Procedia PDF Downloads 409
4916 ADA Tool for Satellite InSAR-Based Ground Displacement Analysis: The Granada Region

Authors: M. Cuevas-González, O. Monserrat, A. Barra, C. Reyes-Carmona, R.M. Mateos, J. P. Galve, R. Sarro, M. Cantalejo, E. Peña, M. Martínez-Corbella, J. A. Luque, J. M. Azañón, A. Millares, M. Béjar, J. A. Navarro, L. Solari

Abstract:

Geohazard prone areas require continuous monitoring to detect risks, understand the phenomena occurring in those regions and prevent disasters. Satellite interferometry (InSAR) has come to be a trustworthy technique for ground movement detection and monitoring in the last few years. InSAR based techniques allow to process large areas providing high number of displacement measurements at low cost. However, the results provided by such techniques are usually not easy to interpret by non-experienced users hampering its use for decision makers. This work presents a set of tools developed in the framework of different projects (Momit, Safety, U-Geohaz, Riskcoast) and an example of their use in the Granada Coastal area (Spain) is shown. The ADA (Active Displacement Areas) tool have been developed with the aim of easing the management, use and interpretation of InSAR based results. It provides a semi-automatic extraction of the most significant ADAs through the application ADAFinder tool. This tool aims to support the exploitation of the European Ground Motion Service (EU-GMS), which will provide consistent, regular and reliable information regarding natural and anthropogenic ground motion phenomena all over Europe.

Keywords: ground displacements, InSAR, natural hazards, satellite imagery

Procedia PDF Downloads 204
4915 Effect of the Truss System to the Flexural Behavior of the External Reinforced Concrete Beams

Authors: Rudy Djamaluddin, Yasser Bachtiar, Rita Irmawati, Abd. Madjid Akkas, Rusdi Usman Latief

Abstract:

The aesthetic qualities and the versatility of reinforced concrete have made it a popular choice for many architects and structural engineers. Therefore, the exploration of natural materials such as gravels and sands as well as lime-stone for cement production is increasing to produce a concrete material. The exploration must affect to the environment. Therefore, the using of the concrete materials should be as efficient as possible. According to its natural behavior of the concrete material, it is strong in compression and weak in tension. Therefore the contribution of the tensile stresses of the concrete to the flexural capacity of the beams is neglected. However, removing of concrete on tension zone affects to the decreasing of flexural capacity. Introduce the strut action of truss structures may an alternative to solve the decreasing of flexural capacity. A series of specimens were prepared to clarify the effect of the truss structures in the concrete beams without concrete on the tension zone. Results indicated that the truss system is necessary for the external reinforced concrete beams. The truss system of concrete beam without concrete on tension zone (BR) could develop almost same capacity to the normal beam (BN). It can be observed also that specimens BR has lower number of cracks than specimen BN. This may be caused by the fact that there was no bonding effect on the tensile reinforcement on specimen BR to distribute the cracks.

Keywords: external reinforcement, truss, concrete beams, flexural behavior

Procedia PDF Downloads 437
4914 Valorization, Conservation and Sustainable Production of Medicinal Plants in Morocco

Authors: Elachouri Mostafa, Fakchich Jamila, Lazaar Jamila, Elmadmad Mohammed, Marhom Mostafa

Abstract:

Of course, there has been a great growth in scientific information about medicinal plants in recent decades, but in many ways this has proved poor compensation, because such information is accessible, in practice, only to a very few people and anyway, rather little of it is relevant to problems of management and utilization, as encountered in the field. Active compounds are used in most traditional medicines and play an important role in advancing sustainable rural livelihoods through their conservation, cultivation, propagation, marketing and commercialization. Medicinal herbs are great resources for various pharmaceutical compounds and urgent measures are required to protect these plant species from their natural destruction and disappearance. Indeed, there is a real danger of indigenous Arab medicinal practices and knowledge disappearing altogether, further weakening traditional Arab culture and creating more insecurity, as well as forsaking a resource of inestimable economic and health care importance. As scientific approach, the ethnopharmacological investigation remains the principal way to improve, evaluate, and increase the odds of finding of biologically active compounds derived from medicinal plants. As developing country, belonging to the Mediterranean basin, Morocco country is endowed with resources of medicinal and aromatic plants. These plants have been used over the millennia for human welfare, even today. Besides, Morocco has a large plant biodiversity, in fact, its medicinal flora account more than 4200 species growing on various bioclimatic zones from subhumide to arid and Saharan. Nevertheless, the human and animal pressure resulting from the increase of rural population needs has led to degradation of this patrimony. In this paper, we focus our attention on ethnopharmacological studies carried out in Morocco. The goal of this work is to clarify the importance of herbs as platform for drugs discovery and further development, to highlight the importance of ethnopharmacological study as approach on discovery of natural products in the health care field, and to discuss the limit of ethnopharmacological investigation of drug discovery in Morocco.

Keywords: Morocco, medicinal plants, ethnopharmacology, natural products, drug-discovery

Procedia PDF Downloads 310
4913 The Thinking of Dynamic Formulation of Rock Aging Agent Driven by Data

Authors: Longlong Zhang, Xiaohua Zhu, Ping Zhao, Yu Wang

Abstract:

The construction of mines, railways, highways, water conservancy projects, etc., have formed a large number of high steep slope wounds in China. Under the premise of slope stability and safety, the minimum cost, green and close to natural wound space repair, has become a new problem. Nowadays, in situ element testing and analysis, monitoring, field quantitative factor classification, and assignment evaluation will produce vast amounts of data. Data processing and analysis will inevitably differentiate the morphology, mineral composition, physicochemical properties between rock wounds, by which to dynamically match the appropriate techniques and materials for restoration. In the present research, based on the grid partition of the slope surface, tested the content of the combined oxide of rock mineral (SiO₂, CaO, MgO, Al₂O₃, Fe₃O₄, etc.), and classified and assigned values to the hardness and breakage of rock texture. The data of essential factors are interpolated and normalized in GIS, which formed the differential zoning map of slope space. According to the physical and chemical properties and spatial morphology of rocks in different zones, organic acids (plant waste fruit, fruit residue, etc.), natural mineral powder (zeolite, apatite, kaolin, etc.), water-retaining agent, and plant gum (melon powder) were mixed in different proportions to form rock aging agents. To spray the aging agent with different formulas on the slopes in different sections can affectively age the fresh rock wound, providing convenience for seed implantation, and reducing the transformation of heavy metals in the rocks. Through many practical engineering practices, a dynamic data platform of rock aging agent formula system is formed, which provides materials for the restoration of different slopes. It will also provide a guideline for the mixed-use of various natural materials to solve the complex, non-uniformity ecological restoration problem.

Keywords: data-driven, dynamic state, high steep slope, rock aging agent, wounds

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4912 Mineralogy and Classification of Altered Host Rocks in the Zaghia Iron Oxide Deposit, East of Bafq, Central Iran

Authors: Azat Eslamizadeh, Neda Akbarian

Abstract:

The Zaghia Iron ore, in 15 km east of a town named Bafq, is located in Precambrian formation of Central Iran in form of a small local deposit. The Volcano-sedimentary rocks of Precambrian-Cambrian age, belonging to Rizu series have spread through the region. Substantial portion of the deposit is covered by alluvial deposits. The rocks hosting the Zaghia iron ore have a main combination of rhyolitic tuffs along with clastic sediments, carbonate include sandstone, limestone, dolomite, conglomerate and is somewhat metamorphed causing them to have appeared as slate and phyllite. Moreover, carbonate rocks are in existence as skarn compound of marble bearing tremolite with mineralization of magnetite-hematite. The basic igneous rocks have dramatically altered into green rocks consist of actinolite-tremolite and chlorite along with amount of iron (magnetite + Martite). The youngest units of ore-bearing rocks in the area are found as dolerite - diabase dikes. The dikes are cutting the rhyolitic tuffs and carbonate rocks.

Keywords: Zaghia, iron ore deposite, mineralogy, petrography Bafq, Iran

Procedia PDF Downloads 519
4911 Network and Sentiment Analysis of U.S. Congressional Tweets

Authors: Chaitanya Kanakamedala, Hansa Pradhan, Carter Gilbert

Abstract:

Social media platforms, such as Twitter, are excellent datasets for understanding human interactions and sentiments. This report explores social dynamics among US Congressional members through a network analysis applied to a dataset of tweets spanning 2008 to 2017 from the ’US Congressional Tweets Dataset’. In this report, we preform network analysis where connections between users (edges) are established based on a similarity threshold: two tweets are connected if the tweets they post are similar. By utilizing the Natural Language Toolkit (NLTK) and NetworkX, we quantified tweet similarity and constructed a graph comprising various interconnected components. Each component represents a cluster of users with closely aligned content. We then preform sentiment analysis on each cluster to explore the prevalent emotions and opinions within these groups. Our findings reveal that despite the initial expectation of distinct ideological divisions typically aligning with party lines, the analysis exposed a high degree of topical convergence across tweets from different political affiliations. The analysis preformed in this report not only highlights the potential of social media as a tool for political communication but also suggests a complex layer of interaction that transcends traditional partisan boundaries, reflecting a complicated landscape of politics in the digital age.

Keywords: natural language processing, sentiment analysis, centrality analysis, topic modeling

Procedia PDF Downloads 20