Search results for: Mohammad Hossein Harirchian
1453 Investigating the Effects of Hydrogen on Wet Cement for Underground Hydrogen Storage Applications in Oil and Gas Wells
Authors: Hamoud Al-Hadrami, Hossein Emadi, Athar Hussain
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Green hydrogen is quickly emerging as a new source of renewable energy for the world. Hydrogen production using water electrolysis is deemed as an environmentally friendly and safe source of energy for transportation and other industries. However, storing a high volume of hydrogen seems to be a significant challenge. Abandoned hydrocarbon reservoirs are considered as viable hydrogen storage options because of the availability of the required infrastructure such as wells and surface facilities. However, long-term wellbore integrity in these wells could be a serious challenge. Hydrogen reduces the compressive strength of a set cement if it gets in contact with the cement slurry. Also, mixing hydrogen with cement slurry slightly increases its density and rheological properties, which need to be considered to have a successful primary cementing operation.Keywords: hydrogen, well bore integrity, clean energy, cementing
Procedia PDF Downloads 2141452 Challenges of Strategies for Improving Sustainability in Urban Historical Context in Developing Countries: The Case of Shiraz Bein Al-Haramein
Authors: Amir Hossein Ashari, Sedighe Erfan Manesh
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One of the problems in developing countries is renovating the historical context and inducing behaviors appropriate to modern life to such a context. This study was conducted using field and library methods in 2012. Similar cases carried out in Iran and developing countries were compared to unveil the strengths and weaknesses of these projects. At present, in the historical context of Shiraz, the distance between two religious shrines of Shahcheragh (Ahmad ibn Musa) and Astaneh (Sayed Alaa al-Din Hossein), which are significant places in religious, cultural, social, and economic terms, is an area full of historic places called Bein Al-Haramein. Unfortunately, some of these places have been worn out and are not appropriate for common uses. The basic strategy of Bein Al-Haramein was to improve social development of Shiraz, to enhance the vitality and dynamism of the historical context of Bein Al-Haramein and to create tourist attractions in order to boost the city's economic and social stability. To this end, the project includes the huge Bein Al-Haramein Commercial Complex which is under construction now. To construct the complex, officials have decided to demolish places of historical value which can lead to irreparable consequences. Iranian urban design has always been based on three elements of bazaars, mosques and government facilities with bazaars being the organic connector of the other elements. Therefore, the best strategy in the above case is to provide for a commercial connection between the two poles. Although this strategy is included in the project, lack of attention to renovation principles in this area and complete destruction of the context will lead to its irreversible damage and will destroy its cultural and historical identity. In urban planning of this project, some important issues have been neglected including: preserving valuable buildings and special old features of the city, rebuilding worn buildings and context to attract trust and confidence of the people, developing new models according to changes, improving the structural position of old context with minimal degradation, attracting partnerships of residents and protecting their rights and finally using potential facilities of the old context. The best strategy for achieving sustainability in Bein Al-Haramein can be the one used in the distance between Santa Maria Novella and Santa Maria Del Fiore churches in historical context where while protecting the historic context and constructions, old buildings were renovated and given different commercial and service uses making them sustainable and dynamic places. Similarly, in Bein Al-Haramein, renovating old constructions and monuments and giving different commercial and other uses to them can help improve the economic and social sustainability of the area.Keywords: Bein Al-Haramein, sustainability, historical context, historical context
Procedia PDF Downloads 4421451 Mutual Authentication for Sensor-to-Sensor Communications in IoT Infrastructure
Authors: Shadi Janbabaei, Hossein Gharaee Garakani, Naser Mohammadzadeh
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Internet of things is a new concept that its emergence has caused ubiquity of sensors in human life, so that at any time, all data are collected, processed and transmitted by these sensors. In order to establish a secure connection, the first challenge is authentication between sensors. However, this challenge also requires some features so that the authentication is done properly. Anonymity, untraceability, and being lightweight are among the issues that need to be considered. In this paper, we have evaluated the authentication protocols and have analyzed the security vulnerabilities found in them. Then an improved light weight authentication protocol for sensor-to-sensor communications is presented which uses the hash function and logical operators. The analysis of protocol shows that security requirements have been met and the protocol is resistant against various attacks. In the end, by decreasing the number of computational cost functions, it is argued that the protocol is lighter than before.Keywords: anonymity, authentication, Internet of Things, lightweight, un-traceability
Procedia PDF Downloads 2931450 The Effect of Computer-Mediated vs. Face-to-Face Instruction on L2 Pragmatics: A Meta-Analysis
Authors: Marziyeh Yousefi, Hossein Nassaji
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This paper reports the results of a meta-analysis of studies on the effects of instruction mode on learning second language pragmatics during the last decade (from 2006 to 2016). After establishing related inclusion/ exclusion criteria, 39 published studies were retrieved and included in the present meta-analysis. Studies were later coded for face-to-face and computer-assisted mode of instruction. Statistical procedures were applied to obtain effect sizes. It was found that Computer-Assisted-Language-Learning studies generated larger effects than Face-to-Face instruction.Keywords: meta-analysis, effect size, L2 pragmatics, comprehensive meta-analysis, face-to-face, computer-assisted language learning
Procedia PDF Downloads 2231449 The Influence of Chevron Angle on Plate Heat Exchanger Thermal Performance with Considering Maldistribution
Authors: Hossein Shokouhmand, Majid Hasanpour
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A new modification to the Strelow method of chevron-type plate heat exchangers (PHX) modeling is proposed. The effects of maldistribution are accounted in the resulting equation. The results of calculations are validated by reported experiences. The good accuracy of heat transfer performance prediction is shown. The results indicate that considering flow maldistribution improve the accuracy of predicting the flow and thermal behavior of the plate exchanger. Additionally, a wide range of the parametric study has been presented which brings out the effects of chevron angle of PHE on its thermal efficiency with considering maldistribution effect. In addition, the thermally optimal corrugation discussed for the chevron-type PHEs.Keywords: chevron angle, plate heat exchangers, maldistribution, strelow method
Procedia PDF Downloads 1901448 Additive White Gaussian Noise Filtering from ECG by Wiener Filter and Median Filter: A Comparative Study
Authors: Hossein Javidnia, Salehe Taheri
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The Electrocardiogram (ECG) is the recording of the heart’s electrical potential versus time. ECG signals are often contaminated with noise such as baseline wander and muscle noise. As these signals have been widely used in clinical studies to detect heart diseases, it is essential to filter these noises. In this paper we compare performance of Wiener Filtering and Median Filtering methods to filter Additive White Gaussian (AWG) noise with the determined signal to noise ratio (SNR) ranging from 3 to 5 dB applied to long-term ECG recordings samples. Root mean square error (RMSE) and coefficient of determination (R2) between the filtered ECG and original ECG was used as the filter performance indicator. Experimental results show that Wiener filter has better noise filtering performance than Median filter.Keywords: ECG noise filtering, Wiener filtering, median filtering, Gaussian noise, filtering performance
Procedia PDF Downloads 5291447 Catalytic Deoxygenation of Propionic Acid in the Vapour Phase
Authors: Hossein Bayahia, Mohammed Saad Motlaq Al-Gahmdi
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The gas-phase deoxygenation of propionic acid was investigated in the presence of Co-Mo catalysts in N2 or H2 flow at 200-400 °C. In the presence of N2 the main product was 3-pentanone with other deoxygenates and some light gases: ethane and ethene. Using H2 flow, the catalyst was active for decarboxylation and decarbonylation of acid and the yields of ethane and ethene. The decarboxylation and decarbonylation reactions increased with increasing temperature. Cobalt-molybdenum supported on alumina showed better performance than bulk catalyst, especially at 400 °C in the presence of N2 for the ketonisation of propionic acid to form 3-pentanone as the main product. Bulk and supported catalysts were characterized by surface area porosity (BET), thermogravimetric analysis (TGA) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of pyridine adsorption.Keywords: deoxygenation, propionic acid, gas-phase, catalyst
Procedia PDF Downloads 2871446 Preliminary Phytopharmacological Evaluation of Methanol and Petroleum Ether Extracts of Selected Vegetables of Bangladesh
Authors: A. Mohammad Abdul Motalib Momin, B. Sheikh Mohammad Adil Uddin, C. Md Mamunur Rashid, D. Sheikh Arman Mahbub, E. Mohammad Sazzad Rahman, F. Abdullah Faruque
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The present study was designed to investigate the antioxidant and cytotoxicity potential of methanol and pet ether extracts of the Lagenaria siceraria (LM, LP), Cucumis sativus (CSM, CSP), Cucurbita maxima (CMM, CMP) plants. For the phytochemical screening, crude extract was tested for the presence of different chemical groups. In Lagenaria siceraria the following groups were identified: alkaloids, steroids, glycosides and saponins for methanol extract and alkaloids, steroids, glycosides, tannins and saponins are for pet ether extract. Glycosides, steroids, alkaloids, saponins and tannins are present in the methanol extract of Cucumis sativus; the pet ether extract has the alkaloids, steroids and saponins. Glycosides, steroids, alkaloids, saponins and tannins are present in both the methanolic and pet ether extract of Cucurbita maxima. In vitro antioxidant activity of the extracts were performed using DPPH radical scavenging, nitric oxide (NO) scavenging, total antioxidant capacity, total phenol content, total flavonoid content, and Cupric Reducing Antioxidant Capacity assays. The most prominent antioxidant activity was observed with the CSM in the DPPH free radical scavenging test with an IC50 value of 1667.23±11.00271 μg/ml as opposed to that of standard ascorbic acid (IC50 value of 15.707± 1.181 μg/ml.) In total antioxidant capacity method, CMP showed the highest activity (427.81±11.4 mg ascorbic acid/g). The total phenolic and flavonoids content were determined by Folin-Ciocalteu Reagent and aluminium chloride colorimetric method, respectively. The highest total phenols and total flavonoids content were found in CMM and LP with the value of 79.06±16.06 mg gallic acid/g & 119.0±1.41 mg quercetin/g, respectively. In nitric oxide (NO) scavenging the most prominent antioxidant activity was observed in CMM with an IC50 value of 8.119± 0.0036 μg/ml. The Cupric reducing capacity of the extracts was strong and dose dependent manner and CSM showed lowest reducing capacity. The cytotoxicity was determined by Brine shrimp lethality test and among these extracts most potent cytotoxicity was shown by CMM with LC50 value 16.98 µg/ml. The obtained results indicate that the investigated plants could be potential sources of natural antioxidants and can be used for various types of diseases.Keywords: antioxidant, cytotoxicity, methanol, petroleum ether
Procedia PDF Downloads 5771445 Complications and Outcomes of Cochlear Implantation in Children Younger than 12 Months: A Multicenter Study
Authors: Alimohamad Asghari, Ahmad Daneshi, Mohammad Farhadi, Arash Bayat, Mohammad Ajalloueyan, Marjan Mirsalehi, Mohsen Rajati, Seyed Basir Hashemi, Nader Saki, Ali Omidvari
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Evidence suggests that Cochlear Implantation (CI) is a beneficial approach for auditory and speech skills improvement in children with severe to profound hearing loss. However, it remains controversial if implantation in children <12 months is safe and effective compared to older children. The present study aimed to determine whether children's ages affect surgical complications and auditory and speech development. The current multicenter study enrolled 86 children who underwent CI surgery at <12 months of age (group A) and 362 children who underwent implantation between 12 and 24 months of age (group B). The Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores were determined pre-impanation, and "one-year" and "two-year" post-implantation. Four complications (overall rate: 4.65%; three minor) occurred in group A and 12 complications (overall rate: 4.41%; nine minor) occurred in group B. We found no statistically significant difference in the complication rates between the groups (p>0.05). The mean SIR and CAP scores improved over time following CI activation in both groups. However, we did not find significant differences in CAP and SIR scores between the groups across different time points. Cochlear implantation is a safe and efficient procedure in children younger than 12 months, providing substantial auditory and speech benefits comparable to children undergoing implantation at 12 to 24 months of age. Furthermore, surgical complications in younger children are similar to those of children undergoing the CI at an older age.Keywords: cochlear implant, Infant, complications, outcome
Procedia PDF Downloads 1081444 An Optimized Method for Calculating the Linear and Nonlinear Response of SDOF System Subjected to an Arbitrary Base Excitation
Authors: Hossein Kabir, Mojtaba Sadeghi
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Finding the linear and nonlinear responses of a typical single-degree-of-freedom system (SDOF) is always being regarded as a time-consuming process. This study attempts to provide modifications in the renowned Newmark method in order to make it more time efficient than it used to be and make it more accurate by modifying the system in its own non-linear state. The efficacy of the presented method is demonstrated by assigning three base excitations such as Tabas 1978, El Centro 1940, and MEXICO CITY/SCT 1985 earthquakes to a SDOF system, that is, SDOF, to compute the strength reduction factor, yield pseudo acceleration, and ductility factor.Keywords: single-degree-of-freedom system (SDOF), linear acceleration method, nonlinear excited system, equivalent displacement method, equivalent energy method
Procedia PDF Downloads 3201443 Normal Meniscal Extrusion Using Ultrasonography during the Different Range of Motion Running Head: Sonography for Meniscal Extrusion
Authors: Arash Sharafat Vaziri, Leila Aghaghazvini, Soodeh Jahangiri, Mohammad Tahami, Roham Borazjani, Mohammad Naghi Tahmasebi, Hamid Rabie, Hesan Jelodari Mamaghani, Fardis Vosoughi, Maryam Salimi
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Aims: It is essential to know the normal extrusion measures in order to detect pathological ones. In this study, we aimed to define some normal reference values for meniscal extrusion in the normal knees during different ranges of motion. Methods: The amount of anterior and posterior portion of meniscal extrusion among twenty-one asymptomatic volunteers (42 knees) were tracked at 0, 45, and 90 degrees of knee flexion using an ultrasound machine. The repeated measures analysis of variance (ANOVA) was used to show the interaction between the amounts of meniscal extrusion and the different degrees of knee flexion. Result: The anterior portion of the lateral menisci at full knee extension (0.59±1.40) and the posterior portion of the medial menisci during 90° flexion (3.06±2.36) showed the smallest and the highest mean amount of extrusion, respectively. The normal average amounts of anterior extrusion were 1.12± 1.17 mm and 0.99± 1.34 mm for medial and lateral menisci, respectively. The posterior meniscal normal extrusions were significantly increasing in both medial and lateral menisci during the survey (F= 20.250 and 11.298; both P-values< 0.001) as they were measured at 2.37± 2.16 mm and 1.53± 2.18 mm in order. Conclusion: The medial meniscus can extrude 1.74± 1.84 mm normally, while this amount was 1.26± 1.82 mm for the lateral meniscus. These measures commonly increased with the rising of knee flexion motion. Likewise, the posterior portion showed more extrusion than the anterior portion on both sides. These measures commonly increased with higher knee flexion.Keywords: meniscal extrusion, ultrasonography, knee
Procedia PDF Downloads 911442 A Study of Indoor Comfort in Affordable Contemporary Courtyard Housing with Outdoor Welfare in Afghan Sustainable Neighborhoods
Authors: Mohammad Saraj Sharifzai, Keisuke Kitagawa, Ahmad Javid Habib Mohammad Kamil Halimee, Daishi Sakaguchi
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The main purpose of this research is to recognize indoor comfort in contemporary Afghan courtyard house with outdoor welfare in housing layout and neighborhood design where sustainability is a local consideration. This research focuses on three new neighborhoods (Gawoond) in three different provinces of Afghanistan. Since 2001, the capital Kabul and major cities including Kandahar, which will be compared with Peshawar city in Pakistan, have faced a fast, rough-and-tumble process of urban innovation. The effects of this innovation necessitate reconsideration of the formation of sustainable urban environments and in-house thermal comfort. The lack of sustainable urban life in many newly developed Afghan neighborhoods can pose a major challenge to the process of sustainable urban development. Several factors can affect the success or failure of new neighborhoods in the context of urban life. For thermal analysis, we divide our research into three different climatic zones. This study is an evaluation of the environmental impacts of the interior comfort of contemporary courtyard housing with the exterior welfare of neighborhood sustainable design strategy in dry and cold, semi-hot and arid, and semi-humid and hot climates in Afghan cities and Peshawar.Keywords: Afghan contemporary courtyard house, neighbourhood, street pattern and housing layout, sustainability, welfare, comfort, climate zone, Afghanistan
Procedia PDF Downloads 4291441 Targeted Effects of Subsidies on Prices of Selected Commodities in Iran Market
Authors: Sayedramin Hashemianesfehani, Seyed Hossein Hosseinilargani
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In this study, we attempt to realize that to what extent the increase in selected commodities in Iran Market is originated from the implementation of the targeted subsidies law. Hence, an econometric model based on existing theories of increasing and transferring prices in order to transferring inflation is developed. In other words, world price index and virtual variables defined for targeted subsidies has significant and positive impact on the producer price index. The obtained results indicated that the targeted subsidies act in Iran has influential long and short-term impacts on producer price indexes. Finally, world prices of dairy products and dairy price with respect to major parameters is carried out to obtain some managerial results.Keywords: econometric models, targeted subsidies, consumer price index (CPI), producer price index (PPI)
Procedia PDF Downloads 3591440 Range Suitability Model for Livestock Grazing in Taleghan Rangelands
Authors: Hossein Arzani, Masoud Jafari Shalamzari, Z. Arzani
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This paper follows FAO model of suitability analysis. Influential factors affecting extensive grazing were determined and converted into a model. Taleghan rangelands were examined for common types of grazing animals as an example. Advantages and limitations were elicited. All range ecosystems’ components affect range suitability but due to the time and money restrictions, the most important and feasible elements were investigated. From which three sub-models including water accessibility, forage production and erosion sensitivity were considered. Suitable areas in four levels of suitability were calculated using GIS. This suitability modeling approach was adopted due to its simplicity and the minimal time that is required for transforming and analyzing the data sets. Managers could be benefited from the model to devise the measures more wisely to cope with the limitations and enhance the rangelands health and condition.Keywords: range suitability, land-use, extensive grazing, modeling, land evaluation
Procedia PDF Downloads 3411439 Comparison of Competitive State Anxiety among Elite and Non-Elite Futsal Players and Its Relationship with Situational Factors
Authors: Hassan Habibi, Hossein Soltani, Amir Moghadam, Najmeh Bakhshi
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The purpose of this study was to compare competitive state anxiety among elite and non-elite futsal players and its relationship with situational factors. 130 non-elite and 70 elite male futsal players participated in the study. Competitive State Anxiety Inventory-2 and situational factors Inventory were applied. Data was analyzed using one-way ANOVA and product moment correlation. Results showed there was significant difference between competitive state anxiety subscales (cognitive anxiety somatic anxiety & self-confidence) and situational factors among elite and non-elite futsal players (P<0.05) but there was no significant correlations between situational factors subscales among elite and non-elite futsal players (P<0.05).Keywords: competitive state anxiety, situational factors, elite players, non-elite players
Procedia PDF Downloads 6501438 Analysis of Delamination in Drilling of Composite Materials
Authors: Navid Zarif Karimi, Hossein Heidary, Giangiacomo Minak, Mehdi Ahmadi
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In this paper analytical model based on the mechanics of oblique cutting, linear elastic fracture mechanics (LEFM) and bending plate theory has been presented to determine the critical feed rate causing delamination in drilling of composite materials. Most of the models in this area used LEFM and bending plate theory; hence, they can only determine the critical thrust force which is an incorporable parameter. In this model by adding cutting oblique mechanics to previous models, critical feed rate has been determined. Also instead of simplification in loading condition, actual thrust force induced by chisel edge and cutting lips on composite plate is modeled.Keywords: composite material, delamination, drilling, thrust force
Procedia PDF Downloads 5151437 Effects of Coastal Structure Construction on Ecosystem
Authors: Afshin Jahangirzadeh, Shatirah Akib, Keyvan Kimiaei, Hossein Basser
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Coastal defense structures were built to protect part of shore from beach erosion and flooding by sea water. Effects of coastal defense structures can be negative or positive. Some of the effects are beneficial in socioeconomic aspect, but environment matters should be given more concerns because it can bring bad consequences to the earth landscape and make the ecosystem be unbalanced. This study concerns on the negative impacts as they are dominant. Coastal structures can extremely impact the shoreline configuration. Artificial structures can influence sediment transport, split the coastal space, etc. This can result in habitats loss and lead to noise and visual disturbance of birds. There are two types of coastal defense structures, hard coastal structure and soft coastal structure. Both coastal structures have their own impacts. The impacts are induced during the construction, maintaining, and operation of the structures.Keywords: ecosystem, environmental impact, hard coastal structures, soft coastal structures
Procedia PDF Downloads 4851436 Evaluation of Reliability Indices Using Monte Carlo Simulation Accounting Time to Switch
Authors: Sajjad Asefi, Hossein Afrakhte
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This paper presents the evaluation of reliability indices of an electrical distribution system using Monte Carlo simulation technique accounting Time To Switch (TTS) for each section. In this paper, the distribution system has been assumed by accounting random repair time omission. For simplicity, we have assumed the reliability analysis to be based on exponential law. Each segment has a specified rate of failure (λ) and repair time (r) which will give us the mean up time and mean down time of each section in distribution system. After calculating the modified mean up time (MUT) in years, mean down time (MDT) in hours and unavailability (U) in h/year, TTS have been added to the time which the system is not available, i.e. MDT. In this paper, we have assumed the TTS to be a random variable with Log-Normal distribution.Keywords: distribution system, Monte Carlo simulation, reliability, repair time, time to switch (TTS)
Procedia PDF Downloads 4261435 Element Distribution and REE Dispersal in Sandstone-Hosted Copper Mineralization within Oligo-Miocene Strata, NE Iran: Insights from Lithostratigraphy and Mineralogy
Authors: Mostafa Feiz, Mohammad Safari, Hossein Hadizadeh
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The Chalpo copper area is located in northeastern Iran, which is part of the structural zone of central Iran and the back-arc basin of Sabzevar. This sedimentary basin accumulated in destructive-oligomiocene sediments is named the Nasr-Chalpo-Sangerd (NCS) basin. The sedimentary layers in this basin originated mainly from Upper Cretaceous ophiolitic rocks and intermediate to mafic-post ophiolitic volcanic rocks, deposited as a nonconformity. The mineralized sandstone layers in the Chalpo area include leached zones (with a thickness of 5 to 8 meters) and mineralized lenses with a thickness of 0.5 to 0.7 meters. Ore minerals include primary sulfide minerals, such as chalcocite, chalcopyrite, and pyrite, as well as secondary minerals, such as covellite, digenite, malachite, and azurite, formed in three stages that comprise primary, simultaneously, and supergene stage. The best agents that control the mineralization in this area include the permeability of host rocks, the presence of fault zones as the conduits for copper oxide solutions, and significant amounts of plant fossils, which create a reducing environment for the deposition of mineralized layers. The calculations of mass changes on copper-bearing layers and primary sandstone layers indicate that Pb, As, Cd, Te, and Mo are enriched in the mineralized zones, whereas SiO₂, TiO₂, Fe₂O₃, V, Sr, and Ba are depleted. The combination of geological, stratigraphic, and geochemical studies suggests that the origin of copper may have been the underlying red strata that contained hornblende, plagioclase, biotite, alkaline feldspar, and labile minerals. Dehydration and hydrolysis of these minerals during the diagenetic process caused the leaching of copper and associated elements by circling fluids, which formed an oxidant-hydrothermal solution. Copper and silver in this oxidant solution might have moved upwards through the basin-fault zones and deposited in the reducing environments in the sandstone layers that have had abundant organic matter. Copper in these solutions was probably carried by chloride complexes. The collision of oxidant and reduced solutions caused the deposition of Cu and Ag, whereas some s elements in oxidant environments (e.g., Fe₂O₃, TiO₂, SiO₂, REEs) become uns in the reduced condition. Therefore, the copper-bearing sandstones in the study area are depleted from these elements resulting from the leaching process. The results indicate that during the mineralization stage, LREEs and MREEs were depleted, but Cu, Ag, and S were enriched. Based on field evidence, it seems that the circulation of connate fluids in the reb-bed strata, produced by diagenetic processes, encountered to reduced facies, which formed earlier by abundant fossil-plant debris in the sandstones, is the best model for precipitating sulfide-copper minerals.Keywords: Chalpo, Oligo-Miocene red beds, sandstone-hosted copper mineralization, mass change, LREEs and MREEs
Procedia PDF Downloads 251434 Alternative Energy and Carbon Source for Biosurfactant Production
Authors: Akram Abi, Mohammad Hossein Sarrafzadeh
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Because of their several advantages over chemical surfactants, biosurfactants have given rise to a growing interest in the past decades. Advantages such as lower toxicity, higher biodegradability, higher selectivity and applicable at extreme temperature and pH which enables them to be used in a variety of applications such as: enhanced oil recovery, environmental and pharmaceutical applications, etc. Bacillus subtilis produces a cyclic lipopeptide, called surfactin, which is one of the most powerful biosurfactants with ability to decrease surface tension of water from 72 mN/m to 27 mN/m. In addition to its biosurfactant character, surfactin exhibits interesting biological activities such as: inhibition of fibrin clot formation, lyses of erythrocytes and several bacterial spheroplasts, antiviral, anti-tumoral and antibacterial properties. Surfactin is an antibiotic substance and has been shown recently to possess anti-HIV activity. However, application of biosurfactants is limited by their high production cost. The cost can be reduced by optimizing biosurfactant production using cheap feed stock. Utilization of inexpensive substrates and unconventional carbon sources like urban or agro-industrial wastes is a promising strategy to decrease the production cost of biosurfactants. With suitable engineering optimization and microbiological modifications, these wastes can be used as substrates for large-scale production of biosurfactants. As an effort to fulfill this purpose, in this work we have tried to utilize olive oil as second carbon source and also yeast extract as second nitrogen source to investigate the effect on both biomass and biosurfactant production improvement in Bacillus subtilis cultures. Since the turbidity of the culture was affected by presence of the oil, optical density was compromised and no longer could be used as an index of growth and biomass concentration. Therefore, cell Dry Weight measurements with applying necessary tactics for removing oil drops to prevent interference with biomass weight were carried out to monitor biomass concentration during the growth of the bacterium. The surface tension and critical micelle dilutions (CMD-1, CMD-2) were considered as an indirect measurement of biosurfactant production. Distinctive and promising results were obtained in the cultures containing olive oil compared to cultures without it: more than two fold increase in biomass production (from 2 g/l to 5 g/l) and considerable reduction in surface tension, down to 40 mN/m at surprisingly early hours of culture time (only 5hr after inoculation). This early onset of biosurfactant production in this culture is specially interesting when compared to the conventional cultures at which this reduction in surface tension is not obtained until 30 hour of culture time. Reducing the production time is a very prominent result to be considered for large scale process development. Furthermore, these results can be used to develop strategies for utilization of agro-industrial wastes (such as olive oil mill residue, molasses, etc.) as cheap and easily accessible feed stocks to decrease the high costs of biosurfactant production.Keywords: agro-industrial waste, bacillus subtilis, biosurfactant, fermentation, second carbon and nitrogen source, surfactin
Procedia PDF Downloads 3011433 Windphil Poetic in Architecture: Energy Efficient Strategies in Modern Buildings of Iran
Authors: Sepideh Samadzadehyazdi, Mohammad Javad Khalili, Sarvenaz Samadzadehyazdi, Mohammad Javad Mahdavinejad
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The term ‘Windphil Architecture’ refers to the building that facilitates natural ventilation by architectural elements. Natural ventilation uses the natural forces of wind pressure and stacks effect to direct the movement of air through buildings. Natural ventilation is increasingly being used in contemporary buildings to minimize the consumption of non-renewable energy and it is an effective way to improve indoor air quality. The main objective of this paper is to identify the strategies of using natural ventilation in Iranian modern buildings. In this regard, the research method is ‘descriptive-analytical’ that is based on comparative techniques. To simulate wind flow in the interior spaces of case studies, FLUENT software has been used. Research achievements show that it is possible to use natural ventilation to create a thermally comfortable indoor environment. The natural ventilation strategies could be classified into two groups of environmental characteristics such as public space structure, and architectural characteristics including building form and orientation, openings, central courtyards, wind catchers, roof, wall wings, semi-open spaces and the heat capacity of materials. Having investigated modern buildings of Iran, innovative elements like wind catchers and wall wings are less used than the traditional architecture. Instead, passive ventilation strategies have been more considered in the building design as for the roof structure and openings.Keywords: natural ventilation strategies, wind catchers, wind flow, Iranian modern buildings
Procedia PDF Downloads 3461432 Application of Analytic Hierarchy Process Model to Weight and Prioritize Challenges and Barriers to Strategic Approach
Authors: Mohammad Mehdi Mohebi, Nima Kazempour, Mohammad Naeim Kazempour
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Strategic thinking enables managers to find out what factors are effective in achieving the desired goals and how these factors create value for the customer. Strategic thinking can be interpreted as a form of mental and inner strength in the manager, who by utilizing it, while considering the conditions of the environment and unstable global environment changes, takes decisions, and plans actions, and designs the strategy of his organization in today's changing and unsustainable business environment. Strategic thinking is very important in today’s business world, because without this thinking, the organization's efforts to achieve developed strategies will not be effective. In this study, through a detailed study of the challenges and barriers to strategic thinking that is carried out by various scholars and experts theoretically and experimentally, 7 major factors were identified. Then, based on these main factors of challenges and related elements, a tool in the form of a questionnaire was developed in order to determine their importance and priority from the perspective of strategic management experts. Using statistical tests the reliability and validity of this instrument, including its structural validity, has been examined and approved using factor analysis. These factors are weighted and prioritized using AHP techniques and the opinions of scholars and experts. Prioritization of barriers to strategic thinking include: lack of participatory management, lack of a systematic approach, difficulty in aligning the organization members, lack of incentive organizational culture, behavioural and internal barriers of managers, lack of key managers and lack of access to timely and accurate information.Keywords: strategic thinking, challenges and barriers to strategic thinking, EN bank, AHP method
Procedia PDF Downloads 5461431 Chromatographic Fingerprint Analysis of Methanolic Extract of Camellia sinensis Linn. Leaves
Authors: Babar Ali, Mohammad Rashid, Showkat Rasool Mir, Mohammad Ali, Saiba Shams
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Background: The plant Camellia sinensis (Theaceae) is an evergreen shrub indigenous to Assam (India) and parts of China and Japan. Traditional Chinese medicine has recommended green tea for headaches, body aches and pains, digestion, enhancement of immune defense, detoxification, as an energizer and to prolong life. The leaves have more than 700 chemical constituents, among which flavanoids, amino acids, vitamins (C, E, K), caffeine and polysaccharides. Adulteration and substitution may affect the quality of formulation containing tea leaves. Standardization of medicinal preparation is essential for further therapeutic results and for global acceptance. Hence, chromatographic fingerprint profiles were carried out for establishing the standards. Materials and methods: TLC studies for methanolic extracts of the leaves of Camellia sinensis were carried out in a new developed solvent system, Toluene: Ethyl acetate: Formic acid (7:3:1). TLC plates were dried in air, visualized in UV at wavelengths 254 nm and 366 nm and photographed. Results: Results provide valuable clue regarding their polarity and selection of solvents for separation of phytochemicals. Fingerprinting of methanolic extract of Camellia sinensis leaves revealed the presence of various phytochemicals in UV at 254 nm and 366 nm. Conclusion: Fingerprint profile is quite helpful in setting up of standards and thus to keep a check on intentional/unintentional adulteration. TLC offers major advantages over other conventional chromatographic techniques such as unsurpassed flexibility (esp. stationary and mobile phase), choice of detection wavelength, user friendly, rapid and cost effective.Keywords: Cammelia sinensis Linn., standardization, methanolic extract, thin layer chromatography
Procedia PDF Downloads 4251430 The Study of Indigenous Communities in Sefidkuh Makran, the Showcase of Prehistoric Societies in the 21st Century, Based on Ethnoarchaeological Studies
Authors: Hossein Vahedi, Zahra Soleymani Fard
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SefidKuh area in Baluchistan, Iran, is one of the impossible areas which the focused archeological investigations have not been on it. In the Sefidkuh area, there are colonies as if they were stopped in the Neolithic and Chalcolithic ages. These colonies exhibit culturally specific behaviors, which their study can reveal much of the cultural nature of the Neolithic, Chalcolithic inhabitants of the region. In the villages of this area, still, circular architecture is used in different types. The political management of the villages in the region is also the responsibility of Khan, whose characteristics can be compared to the prehistoric era. These people's livelihoods include hunting, animal husbandry, horticulture, and limited crop storage. Residents of Sefidkuh use the exchange of goods to obtain needed supplies that they themselves cannot produce. In this area, there are central location villages that are quite similar to the cluster model, and the Great Khan leads the surrounding villages.Keywords: archaeology, social structure, neolithic, chalcolithic, Sefidkuh, Baluchistan
Procedia PDF Downloads 1181429 Increasing Sustainability Using the Potential of Urban Rivers in Developing Countries with a Biophilic Design Approach
Authors: Mohammad Reza Mohammadian, Dariush Sattarzadeh, Mir Mohammad Javad Poor Hadi Hosseini
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Population growth, urban development and urban buildup have disturbed the balance between the nature and the city, and so leading to the loss of quality of sustainability of proximity to rivers. While in the past, the sides of urban rivers were considered as urban green space. Urban rivers and their sides that have environmental, social and economic values are important to achieve sustainable development. So far, efforts have been made at various scales in various cities around the world to revitalize these areas. On the other hand, biophilic design is an innovative design approach in which attention to natural details and relation to nature is a fundamental concept. The purpose of this study is to provide an integrated framework of urban design using the potential of urban rivers (in order to increase sustainability) with a biophilic design approach to be used in cities in developing countries. The methodology of the research is based on the collection of data and information from research and projects including a study on biophilic design, investigations and projects related to the urban rivers, and a review of the literature on sustainable urban development. Then studying the boundary of urban rivers is completed by examining case samples. Eventually, integrated framework of urban design, to design the boundaries of urban rivers in the cities of developing countries is presented regarding the factors affecting the design of these areas. The result shows that according to this framework, the potential of the river banks is utilized to increase not only the environmental sustainability but also social, economic and physical stability with regard to water, light, and the usage of indigenous materials, etc.Keywords: urban rivers, biophilic design, urban sustainability, nature
Procedia PDF Downloads 2881428 Determining Efficiency of Frequency Control System of Karkheh Power Plant in Main Network
Authors: Ferydon Salehifar, Hassan Safarikia, Hossein Boromandfar
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Karkheh plant in Iran's Khuzestan province and is located in the city Andimeshk. The plant has a production capacity of 400 MW units with water and three hours. One of the important parameters of each country's power grid stability is the stability of the power grid is affected by the voltage and frequency In plants, the amount of active power frequency control is done so that when the unit is placed in the frequency control their productivity is a function of frequency and output power varies with frequency. Produced by hydroelectric power plants with the water level behind the dam has a direct relationship And to decrease and increase the water level behind the dam in order to reduce the power output increases But these changes have a different interval is due to some mechanical problems such as turbine cavitation and vibration are limited. In this study, the range of the frequency control can be Karkheh manufacturing plants have been identified and their effectiveness has been determined.Keywords: Karkheh power, frequency control system, active power, efficiency
Procedia PDF Downloads 6201427 Scouring Rate Pattern/Monitoring at Coastal and Offshore Structures
Authors: Ahmad Saifullah Mazlan, Hossein Basser, Shatirah Akib
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Scouring pattern evaluation and measuring its depth around coastal and offshore structures is very essential issue to assure the safety of the structures as well as providing needed design parameters. Scouring is known as one of the important phenomena which threatens the safety of infrastructures. Several countermeasures have been developed to control scouring by protecting the structures against water flow attack directly or indirectly by changing the water flow pattern. Recently, monitoring methods for estimating water flow pattern and scour depth are studied to track the safety of structures. Since most of studies regarding scouring is related to monitoring scouring around piers in rivers therefore it is necessary to develop researches investigating scouring around piers in coastal and offshore areas. This paper describes a review of monitoring methods may be used for detecting scour depth around piers in coastal and offshore structures.Keywords: scour, monitoring, pier, coastal, offshore
Procedia PDF Downloads 6441426 Biosynthesis of Silver Nanoparticles Using Zataria multiflora Extract, and Study of Antibacterial Effects on UTI Bacteria (MDR)
Authors: Mohammad Hossein Pazandeh, Monir Doudi, Sona Rostampour Yasouri
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Irregular consumption of current antibiotic makes increases of antibiotic resistance between urin pathogens on all worlds. This study selected based on this great community problem. The aim of this study was the biosynthesis of silver nanoparticles from Zataria multiflora extract and then to investigate its antibacterial effect on gram-negative bacilli common in Urinary Tract Infections (UTI) and MDR. The plant used in the present research was Zataria multiflora whose extract was prepared through Soxhlet extraction method. Green synthesis condition of silver nanoparticles was investigated in terms of three parameters including the extract amount, concentration of silver nitrate salt, and temperature. The seizes of nanoparticles were determined by Zetasizer. In order to identify synthesized silver nanoparticles Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD) methods were used. For evaluating the antibacterial effects of nanoparticles synthesized through biological method different concentrations of silver nanoparticles were studied on 140 cases of Muliple Drug Resistance (MDR) bacteria strains Escherichia coli, Klebsiella pneumoniae, Enterobacter aerogenes, Proteus vulgaris,Citrobacter freundii, Acinetobacter bumanii and Pseudomonas aeruginosa, (each genus of bacteria, 20 samples), which all were MDR and cause urinary tract infections , for identification of bacteria were used of Polymerase Chain Reaction (PCR) test and laboratory methods (Agar well diffusion and Microdilution methods) to assess their sensitivity to Nanoparticles. The data were analyzed using SPSS software by nonparametric Kruskal-Wallis and Mann-Whitney tests. Significant results were found about the effects of silver nitrate concentration, different amounts of Zataria multiflora extract, and temperature on nanoparticles; that is, by increasing the concentration of silver nitrate, extract amount, and temperature, the sizes of synthesized nanoparticles declined. However, the effect of above mentioned factors on particles diffusion index was not significant. Based on the TEM results, particles were mainly spherical shape with a diameter range of 25 to 50 nm. The results of XRD Analysis indicated the formation of Nanostructures and Nanocrystals of silver.. The obtained results of antibacterial effects of different concentrations of silver nanoparticles on according to agar well diffusion and microdilution method, biologically synthesized nanoparticles showed 1000 mg /ml highest and lowest mean inhibition zone diameter in E.coli , Acinetobacter bumanii 23 and 15mm, respectively. MIC was observed for all of bacteria 125mg/ml and for Acinetobacter bumanii 250mg/ml.Comparing the growth inhibitory effect of chemically synthesized Nanoparticles and biologically synthesized Nanoparticles showed that in the chemical method the highest growth inhibition belonged to the concentration of 62.5 mg /ml. The inhibitory effect on the growth all of bacteria causes of urine infection and MDR was observed and by increasing silver ion concentration in Nanoparticles, antibacterial activity increased. Generally, the biological synthesis can be considered an efficient way not only in making Nanoparticles but also for having anti-bacterial properties. It is more biocompatible and may be possess less toxicity than the Nanoparticles synthesized chemically.Keywords: biosynthesis, MDR bacteria, silver nanoparticles, UTI
Procedia PDF Downloads 501425 New Neuroplasmonic Sensor Based on Soft Nanolithography
Authors: Seyedeh Mehri Hamidi, Nasrin Asgari, Foozieh Sohrabi, Mohammad Ali Ansari
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New neuro plasmonic sensor based on one dimensional plasmonic nano-grating has been prepared. To record neural activity, the sample has been exposed under different infrared laser and then has been calculated by ellipsometry parameters. Our results show that we have efficient sensitivity to different laser excitation.Keywords: neural activity, Plasmonic sensor, Nanograting, Gold thin film
Procedia PDF Downloads 3981424 Numerical Iteration Method to Find New Formulas for Nonlinear Equations
Authors: Kholod Mohammad Abualnaja
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A new algorithm is presented to find some new iterative methods for solving nonlinear equations F(x)=0 by using the variational iteration method. The efficiency of the considered method is illustrated by example. The results show that the proposed iteration technique, without linearization or small perturbation, is very effective and convenient.Keywords: variational iteration method, nonlinear equations, Lagrange multiplier, algorithms
Procedia PDF Downloads 545