Search results for: oxygen steam
615 Using Medicinal Herbs in Designing Green Roofs
Authors: Mohamad Javad Shakouri, Behshad Riahipour
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Today, the use of medicinal herbs in architecture and green space has a significant effect on the process of calming human and increases the reliability coefficient of design and design flexibility. The current research was conducted with the aim to design green roof and investigate the effect of medicinal herbs such as cress, leek, fenugreek, beet, sweet fennel, green basil, purple basil, and purslane on reducing the number of environmental pollutants (copper, zinc, and cadmium). Finally, the weight of the dry plant and the concentration of elements zinc, lead, and cadmium in the herbs was measured. According to the results, the maximum dry weight (88.10 and 73.79 g) was obtained in beet and purslane respectively and the minimum dry weight (24.12 and 25.21) was obtained in purple basil, and green basil respectively. The maximum amount of element zinc (235 and 213 mg/kg) and the maximum amount of lead (143 mg/kg) were seen in sweet fennel and purple basil. In addition, the maximum amount of cadmium (13 mg/kg) was seen in sweet fennel and purple basil and the minimum amount of lead and cadmium (78 and 7 mg/kg) was seen in green basil, and the minimum amount of zinc (110 mg/kg) was seen in leek. On the other hand, the absorption amount of element lead in the herbs beet and purslane was the same and both absorbed 123 mg/kg lead. Environmentally, if green roofs are implemented extensively and in wide dimensions in urban spaces, they will purify and reduce pollution significantly by absorbing carbon dioxide and producing oxygen.Keywords: medicinal herbs, green space, green roof, heavy metals, lead, green basil
Procedia PDF Downloads 163614 An Integrated Power Generation System Design Developed between Solar Energy-Assisted Dual Absorption Cycles
Authors: Asli Tiktas, Huseyin Gunerhan, Arif Hepbasli
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Solar energy, with its abundant and clean features, is one of the prominent renewable energy sources in multigeneration energy systems where various outputs, especially power generation, are produced together. In the literature, concentrated solar energy systems, which are an expensive technology, are mostly used in solar power plants where medium-high capacity production outputs are achieved. In addition, although different methods have been developed and proposed for solar energy-supported integrated power generation systems by different investigators, absorption technology, which is one of the key points of the present study, has been used extensively in cooling systems in these studies. Unlike these common uses mentioned in the literature, this study designs a system in which a flat plate solar collector (FPSC), Rankine cycle, absorption heat transformer (AHT), and cooling systems (ACS) are integrated. The system proposed within the scope of this study aims to produce medium-high-capacity electricity, heating, and cooling outputs using a technique different from the literature, with lower production costs than existing systems. With the proposed integrated system design, the average production costs based on electricity, heating, and cooling load production for similar scale systems are 5-10% of the average production costs of 0.685 USD/kWh, 0.247 USD/kWh, and 0.342 USD/kWh. In the proposed integrated system design, this will be achieved by increasing the outlet temperature of the AHT and FPSC system first, expanding the high-temperature steam coming out of the absorber of the AHT system in the turbine up to the condenser temperature of the ACS system, and next directly integrating it into the evaporator of this system and then completing the AHT cycle. Through this proposed system, heating and cooling will be carried out by completing the AHT and ACS cycles, respectively, while power generation will be provided because of the expansion of the turbine. Using only a single generator in the production of these three outputs together, the costs of additional boilers and the need for a heat source are also saved. In order to demonstrate that the system proposed in this study offers a more optimum solution, the techno-economic parameters obtained based on energy, exergy, economic, and environmental analysis were compared with the parameters of similar scale systems in the literature. The design parameters of the proposed system were determined through a parametric optimization study to exceed the maximum efficiency and effectiveness and reduce the production cost rate values of the compared systems.Keywords: solar energy, absorption technology, Rankine cycle, multigeneration energy system
Procedia PDF Downloads 58613 Physical and Chemical Parameters of Lower Ogun River, Ogun State, Nigeria
Authors: F.I. Adeosun, A.A. Idowu, D.O. Odulate,
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The aims of carrying out this experiment were to determine the water quality and to investigate if the various human and ecological activities around the river have any effect on the physico-chemical parameters of the river’s resources with a view to effectively utilizing these resources. Water samples were collected from two stations on the surface water of Lower Ogun River Akomoje biweekly for a period of 5 months (January to May, 2011). Results showed that temperature ranged between 24.0-30.7oC, transparency (0.53-1.00 m), depth (1.0-3.88 m), alkalinity (4.5-14.5 mg/l), nitrates (0.235-5.445 mg/l), electrical conductivity (140-190µS/cm), dissolved oxygen (4.12-5.32 mg/l), phosphates (0.02 mg/l-0.7 5 mg/l) and total dissolved solids (70-95).The parameters at the deep end (station A) accounted for the bulk of the highest values; there was however no significant differences between the stations at P˂0.05 with the exception of transparency, depth, total dissolved solids and electrical conductivity. The phosphate value was relatively low which accounted for the low productivity and high transparency. The results obtained from the physico-chemical parameters agreed with the limits set by both national and international bodies for drinking and fish growth. It was however observed that during the period of data collection, catch was low and this could be attributed to low level of primary productivity due to the quality of physico-chemical parameters of the water. It is recommended that the agencies involved in the management of the river should put the right policies in place that will effectively enhance proper exploitation of the water resources. More research should also be carried out on the physico-chemical parameters since this work only studied the water for five months.Keywords: physical, chemical, parameters, water quality, Ogunriver
Procedia PDF Downloads 681612 Surface Water Pollution by Open Refuse Dumpsite in North Central of Nigeria
Authors: Abimbola Motunrayo Folami, Ibironke Titilayo Enitan, Feroz Mohomed Swalaha
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Water is a vital resource that is important in ensuring the growth and development of any country. To sustain the basic human needs and the demands for agriculture, industry, conservational and ecosystem, enough quality and quantity water is needed. Contamination of water resources is now a global and public health concern. Hence, this study assessed the water quality of Ndawuse River by measuring the physicochemical parameters and heavy metals concentrations of the river using standard methods. In total, 16 surface water samples were obtained from five locations along the river, from upstream to downstream as well as samples from the dumpsite. The results obtained were compared with the standard limits set by both the World Health Organization and the Federal Environmental Protection Agency for domestic purposes. The results of the measured parameters indicated that biological oxygen demand (85.88 mg/L), turbidity (44.51 NTU), Iron (0.014 - 3.511 mg /L) and chromium (0.078 - 0.14 mg /L) were all above the standard limits. The results further showed that the quality of surface water is being significantly affected by human activities around the Ndawuse River which could pose an adverse health risk to several communities that rely on this river as their primary source of water. Therefore, there is a need for strict enforcement of environmental laws to protect the aquatic ecosystem and to avoid long term cumulative exposure risk that heavy metals may pose on human health.Keywords: Abuja, contaminants, heavy metals, Ndawuse River, Nigeria, surface water
Procedia PDF Downloads 157611 Geothermal Resources to Ensure Energy Security During Climate Change
Authors: Debasmita Misra, Arthur Nash
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Energy security and sufficiency enables the economic development and welfare of a nation or a society. Currently, the global energy system is dominated by fossil fuels, which is a non-renewable energy resource, which renders vulnerability to energy security. Hence, many nations have begun augmenting their energy system with renewable energy resources, such as solar, wind, biomass and hydro. However, with climate change, how sustainable are some of the renewable energy resources in the future is a matter of concern. Geothermal energy resources have been underexplored or underexploited in global renewable energy production and security, although it is gaining attractiveness as a renewable energy resource. The question is, whether geothermal energy resources are more sustainable than other renewable energy resources. High-temperature reservoirs (> 220 °F) can produce electricity from flash/dry steam plants as well as binary cycle production facilities. Most of the world’s high enthalpy geothermal resources are within the seismo-tectonic belt. However, exploration for geothermal energy is of great importance in conventional geothermal systems in order to improve its economic viability. In recent years, there has been an increase in the use and development of several exploration methods for geo-thermal resources, such as seismic or electromagnetic methods. The thermal infrared band of the Landsat can reflect land surface temperature difference, so the ETM+ data with specific grey stretch enhancement has been used to explore underground heat water. Another way of exploring for potential power is utilizing fairway play analysis for sites without surface expression and in rift zones. Utilizing this type of analysis can improve the success rate of project development by reducing exploration costs. Identifying the basin distribution of geologic factors that control the geothermal environment would help in identifying the control of resource concentration aside from the heat flow, thus improving the probability of success. The first step is compiling existing geophysical data. This leads to constructing conceptual models of potential geothermal concentrations which can then be utilized in creating a geodatabase to analyze risk maps. Geospatial analysis and other GIS tools can be used in such efforts to produce spatial distribution maps. The goal of this paper is to discuss how climate change may impact renewable energy resources and how could a synthesized analysis be developed for geothermal resources to ensure sustainable and cost effective exploitation of the resource.Keywords: exploration, geothermal, renewable energy, sustainable
Procedia PDF Downloads 154610 The Effect of Particulate Matter on Cardiomyocyte Apoptosis Through Mitochondrial Fission
Authors: Tsai-chun Lai, Szu-ju Fu, Tzu-lin Lee, Yuh-Lien Chen
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There is much evidence that exposure to fine particulate matter (PM) from air pollution increases the risk of cardiovascular morbidity and mortality. According to previous reports, PM in the air enters the respiratory tract, contacts the alveoli, and enters the blood circulation, leading to the progression of cardiovascular disease. PM pollution may also lead to cardiometabolic disturbances, increasing the risk of cardiovascular disease. The effects of PM on cardiac function and mitochondrial damage are currently unknown. We used mice and rat cardiomyocytes (H9c2) as animal and in vitro cell models, respectively, to simulate an air pollution environment using PM. These results indicate that the apoptosis-related factor PUMA, a regulator of apoptosis upregulated by p53, is increased in mice treated with PM. Apoptosis was aggravated in cardiomyocytes treated with PM, as measured by TUNEL assay and Annexin V/PI. Western blot results showed that CASPASE3 was significantly increased and BCL2 (B-cell lymphoid 2) was significantly decreased under PM treatment. Concurrent exposure to PM increases mitochondrial reactive oxygen species (ROS) production by MitoSOX Red staining. Furthermore, using Mitotracker staining, PM treatment significantly shortened mitochondrial length, indicating mitochondrial fission. The expression of mitochondrial fission-related proteins p-DRP1 (phosphodynamics-related protein 1) and FIS1 (mitochondrial fission 1 protein) was significantly increased. Based on these results, the exposure to PM worsens mitochondrial function and leads to cardiomyocyte apoptosis.Keywords: particulate matter, cardiomyocyte, apoptosis, mitochondria
Procedia PDF Downloads 103609 Assessment of Acute Cardiovascular Responses to Moderate and Vigorous Intensity Aerobic Exercises in Sedentary Adults and Amateur Athletes
Authors: Caner Yilmaz, Zuhal Didem Takinaci
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Introduction: Today, our knowledge about the effects of physical activity performed at the different intensity of the cardiovascular system are still not clear. Therefore, to contribute to the literature, in our study, sedentary individuals and amateur athletes were assessed in a single session with the aim of evaluating the cardiovascular effects of the moderate and severe exercise. Methods: 80 participants (40 amateur athletes and 40 sedentary, young adults) participated in our study. Participants were divided into two groups: amateur athletes (mean age: 25.0 ± 3.6 yrs) and sedentary in group II (mean age: 23.8 ± 3.7 yrs). Participants in both groups were assessed twice, namely, firstly, at moderate intensity (5km/h 30 min. walking) and secondly at the vigorous intensity (8km/h 20 min. jogging). Participants’ SBP (Systolic Blood Pressure), DBP (Diastolic Blood Pressure), HR (Heart Rate), SpO₂ (Oxygen Saturation), BT (Body Temperature) and RR (Respiratory Rate) were measured. Results: In our study, the findings showed that after moderate-intensity aerobic exercise, change in SBP, DBP, and SpO₂ were significantly higher in Group II (p < 0.05). After the severe intensity aerobic exercises, change in SBP, SpO₂, HR, and RR was significantly higher in Group II (p < 0.05). The BORG score of Group II was significantly higher after both moderate and severe intensity aerobic exercise (p < 0.05). Conclusion: The cardiovascular responses of amateur athletes were closer to initial values, and the differences between the two groups were increased in direct proportion to the intensity of the exercise. Both exercise intensities could be adequate.Keywords: aerobic, exercise, sedantary, cardi̇ovascular
Procedia PDF Downloads 290608 Synthesis and Theoretical Calculations of Carbazole Substituted Pyridopyrimidine Urea/Thioure Derivatives and Studies Their PPO Enzyme Activity
Authors: Arleta Rifati Nixha, Mustafa Arslan, Adem Ergün, Nahit Gencer
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Polyphenol oxidase (PPO), sometimes referred to as phenol oxidase, catecholase, phenolase, catechol oxidase, or even tyrosinase, is considered to be an o-dipenol. PPO (EC 1.14.18.1), a multifunctional copper containing enzyme, is widely distributed in nature. It catalyzes two distinct reactions of melanin synthesis: a hydroxylation of monophenols to o-diphenols (monophenolase activity) and an oxidation of o-diphenols to o-quinones (diphenolase activity), both using molecular oxygen. Additionaly, investigation demonstrated that various dermatological disorders, such as age spots and freckle, were caused by the accumulation of an excessive level of epidermal pigmentation. Tyrosinase has also been linked to Parkinson’s and other neurodegenerative diseases. Nitrogen heterocycles have received a great deal of attention in the literature because of biological properties. Especially, among these heterocyclic systems, pyridine containing compounds have been the subject of expanding research efforts in heteroaromatic and biological chemistry. The pyrido [2,3-d] pyrimidine heterocycles, which are those annelated to a pyrimidine ring, are important because of their wide range of biological and pharmaceutical applications (i.e., bronchodilators, vasodilators) and their anti-allergic, cardiotonic, antihypertensive, and hepatoprotective activities. In this study series of 12 new carbazole substituted pyridopyrimidine urea(thiourea) derivatives were synthesized and evaluated effect on PPO. Additionally, we presented structure-activity relationship analyses and theoretical calculations of the compounds.Keywords: carbazole, pyridopyrimidine, urea, thiourea, tyrosinase inhibitors
Procedia PDF Downloads 439607 Copper/Nickel Sulfide Catalyst Electrodeposited on Nickel Foam for Efficient Water Splitting
Authors: Hamad Almohamadi, Nabeel Alharthi, Majed Alamoudi
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Biphasic electrodes featuring CuSx/NiSx electrodeposited on nickel foam have been investigated for their electrocatalytic activity in water splitting. The study investigates the impacts of an S-vacancy induced biphasic design on the overpotential and Tafel slope. According to the findings, the NiSx/CuSx/NF electrode with S-vacancy defects displays stronger oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activity with lower overpotential and a steeper Tafel slope than the non-defect sample. NiSx/CuSx/NF exhibits the lowest overpotential value of 212 mV vs reversible hydrogen electrode (RHE) for OER and −109 mV vs RHE for HER at 10 mA cm−2. Tafel slope of 25.4 mV dec−1 for OER and −108 mV dec−1 for OER found of that electrode. The electrochemical surface area (ECSA) and diffusion impedance of the electrode is calculated. The maximum ECSA, lowest series resistance and lowest charge transfer resistance are found in the *NiSx/CuSx/NF sample with S-vacancy defects, showing increased electrical conductivity and quick charge transfer kinetics. The *NiSx/CuSx/NF electrode was found to be stable for 80 hours in pure water splitting and 20 hours in sea-water splitting. The investigation comes to the conclusion that the enhanced water splitting activity and electrical conductivity of the electrode are caused by S-vacancy defects resulting in improved water splitting performance.Keywords: water splitting, electrocatalyst, biphasic design, electrodeposition
Procedia PDF Downloads 74606 Biogas Production from Pistachio (Pistacia vera L.) Processing Waste
Authors: İ. Çelik, Goksel Demirer
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Turkey is the third largest producer of pistachio (Pistacia vera L.) after Iran and United States. Harvested pistachio nuts are covered with organic hull which is removed by de-hulling process. Most of the pistachio by-products which are produced during de-hulling process are considered as agricultural waste and often mixed with soil, to a lesser extent are used as feedstuff by local livestock farmers and a small portion is used as herbal medicine. Due to its high organic and phenolic content as well as high solids concentration, pistachio processing wastes create significant waste management problems unless they are properly managed. However, there is not a well-established waste management method compensating the waste generated during the processing of pistachios. This study investigated the anaerobic treatability and biogas generation potential of pistachio hull waste. The effect of pre-treatment on biogas generation potential was investigated. For this purpose, Biochemical Methane Potential (BMP) Assays were conducted for two Chemical Oxygen Demand (COD) concentrations of 22 and 33 g tCOD l-1 at the absence and presence of chemical and thermal pre-treatment methods. The results revealed anaerobic digestion of the pistachio de-hulling wastes and subsequent biogas production as a renewable energy source are possible. The observed percent COD removal and methane yield values of the pre-treated pistachio de-hulling waste samples were significantly higher than the raw pistachio de-hulling waste. The highest methane yield was observed as 213.4 ml CH4/g COD.Keywords: pistachio de-hulling waste, biogas, renewable energy, pre-treatment
Procedia PDF Downloads 215605 Monodisperse Hallow Sandwich MOF for the Catalytic Oxidation of Benzene at Room Temperature
Authors: Srinivasapriyan Vijayan
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Phenol is one of the most vital chemical in industry. Nowadays, phenol production is based upon the three-step cumene process, which involves a hazardous cumene hydroperoxide intermediate and produces nearly equimolar amounts of acetone as a coproduct. An attractive route in phenol production is the direct one-step selective hydroxylation of benzene using eco-friendly oxidants such as O2, N2O, and H2O2. In particular, the direct hydroxylation of benzene to form phenol with O2 has recently attracted extensive research attention because this process is green clean and eco-friendly. However, most of the catalytic systems involving O2 have a low rate of hydroxylation because the direct introduction of hydroxyl functionality into benzene is challenging. Almost all the developed catalytic systems require an elevated temperature and suffer from low conversion because of the notoriously low reactivity of aromatic C–H bonds. Moreover, increased reactivity of phenol relative to benzene makes the selective oxidation of benzene to phenol very difficult, especially under heating conditions. Hollow spheres, a very fascinating class of materials with good permeation and low density, highly monodisperse MOF hollow sandwich spheres have been rationally synthesized using monodisperse polystyrene (PS) nanoparticles as templates through a versatile step-by-step self-assembly strategy. So, our findings could pave the way toward highly efficient nonprecious catalysts for low-temperature oxidation reactions in heterogeneous catalysis. Because it is easy post-reaction separation, its cheap, green and recyclable.Keywords: benzene hydroxylation, Fe-based metal organic frameworks, molecular oxygen, phenol
Procedia PDF Downloads 214604 Functionalized Carbon-Base Fluorescent Nanoparticles for Emerging Contaminants Targeted Analysis
Authors: Alexander Rodríguez-Hernández, Arnulfo Rojas-Perez, Liz Diaz-Vazquez
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The rise in consumerism over the past century has resulted in the creation of higher amounts of plasticizers, personal care products and other chemical substances, which enter and accumulate in water systems. Other sources of pollutants in Neotropical regions experience large inputs of nutrients with these pollutants resulting in eutrophication of water which consume large quantities of oxygen, resulting in high fish mortality. This dilemma has created a need for the development of targeted detection in complex matrices and remediation of emerging contaminants. We have synthesized carbon nanoparticles from macro algae (Ulva fasciata) by oxidizing the graphitic carbon network under extreme acidic conditions. The resulting material was characterized by STEM, yielding a spherical 12 nm average diameter nanoparticles, which can be fixed into a polysaccharide aerogel synthesized from the same macro algae. Spectrophotometer analyses show a pH dependent fluorescent behavior varying from 450-620 nm in aqueous media. Heavily oxidized edges provide for easy functionalization with enzymes for a more targeted analysis and remediation technique. Given the optical properties of the carbon base nanoparticles and the numerous possibilities of functionalization, we have developed a selective and robust targeted bio-detection and bioremediation technique for the treatment of emerging contaminants in complex matrices like estuarine embayment.Keywords: aerogels, carbon nanoparticles, fluorescent, targeted analysis
Procedia PDF Downloads 243603 Estimation of World Steel Production by Process
Authors: Reina Kawase
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World GHG emissions should be reduced 50% by 2050 compared with 1990 level. CO2 emission reduction from steel sector, an energy-intensive sector, is essential. To estimate CO2 emission from steel sector in the world, estimation of steel production is required. The world steel production by process is estimated during the period of 2005-2050. The world is divided into aggregated 35 regions. For a steel making process, two kinds of processes are considered; basic oxygen furnace (BOF) and electric arc furnace (EAF). Steel production by process in each region is decided based on a current production capacity, supply-demand balance of steel and scrap, technology innovation of steel making, steel consumption projection, and goods trade. World steel production under moderate countermeasure scenario in 2050 increases by 1.3 times compared with that in 2012. When domestic scrap recycling is promoted, steel production in developed regions increases about 1.5 times. The share in developed regions changes from 34 %(2012) to about 40%(2050). This is because developed regions are main suppliers of scrap. 48-57% of world steel production is produced by EAF. Under the scenario which thinks much of supply-demand balance of steel, steel production in developing regions increases is 1.4 times and is larger than that in developed regions. The share in developing regions, however, is not so different from current level. The increase in steel production by EAF is the largest under the scenario in which supply-demand balance of steel is an important factor. The share reaches 65%.Keywords: global steel production, production distribution scenario, steel making process, supply-demand balance
Procedia PDF Downloads 450602 Activation of Mirror Neuron System Response to Drumming Training: A Functional Magnetic Resonance Imaging Study
Authors: Manal Alosaimi
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Many rehabilitation strategies exist to aid persons with neurological disorders relearn motor skills through intensive training. Evidence supporting the theory that cortical areas involved in motor execution can be triggered by observing actions performed by others is attributed to the function of the mirror neuron system (MNS) indicates that activation of the MNS is associated with improvements in physical action and motor learning. Therefore, it is important to investigate the relationship between motor training (in this case, playing the drums) and the activation of the MNS. To achieve this, 15 healthy right-handed participants received drum-kit training for 21 weeks, during which time blood oxygen level-dependent (BOLD) signals were monitored in the brain using functional magnetic resonance imaging (fMRI). Participants were required to perform action–observation and action–execution fMRI tasks. The main results are that BOLD signals in classical regions of the MNS such as supramarginal gyri, inferior parietal lobule, and supplementary motor area increase significantly over the training period. Activation of these areas indicates that passive-observation of others performing these same skills may facilitate recovery of persons suffering from neurological disorders, and complement conventional rehabilitation programs that focus on action execution or intense training.Keywords: fMRI, mirror neuron system, magnetic resonance imaging, neuroplasticity, drumming, learning, music, action observation, action execution
Procedia PDF Downloads 37601 Organic Geochemical Characterization of the Ordovician Source Rock in the Chotts Basin, Southern Tunisia
Authors: Anis Belhaj Mohamed, Moncef Saidi, Mohamed Soussi, Ibrahim Bouazizi, Monia Ben Jrad
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This paper summarizes the results of Rock-Eval pyrolysis and biomarker data of shale samples collected from the Ordovician age (Llanvirnian-Llandeilian) (Azzel Formation) in the Chotts basin southern part of Tunisia. The results are supported by analysis of cutting samples from wells. The Azzel shales has poor to moderate, occasionally good, potential for sourcing oil and gas with Total Organic Carbon (TOC) content varying from 0.80 to 4.49 % and petroleum potential (PP) values varying between 0.68 to 9.20 Kg of HC/t rock in Baguel and Alaguia wells. However, the Azzel Formation show poor to fair TOC and PP in Elfranig and HajBrahim wells not exceeding 1.10% and 1.05 kg HC/t of rock respectively. The Hydrogen Index (HI) and the Oxygen Index (OI) values of 95–165 mg S2/g TOC and of 33–108 mg CO2/g rock relatively show that the Ordovician shales exhibit type II Kerogen that reached the main oil window stage and that the organic matter was bad preserved, Tmax values of 435 – 448°C indicate the organic matter is mature. The biomarker features of the extract samples are characterized by high proportion of tricyclic terpanes that are dominated by C23 and C21 tricyclic terpanes. The hopanes fraction is dominated by C29 and C30 hopanes. The Ordovician shales show a predominance of C27 over C29 steranes (C27/C29>1) and relatively high proportions of diasteranes supporting the shaly character of the source rock.Keywords: biomarkers, organic geochemistry, ordovician source rock, diasteranes
Procedia PDF Downloads 505600 Design, Synthesis and Anti-Inflammatory Activity of Some Coumarin and Flavone Derivatives Containing 1,4 Dioxane Ring System
Authors: Asif Husain, Shah Alam Khan
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Coumarins and flavones are oxygen containing heterocyclic compounds which are present in various biologically active compounds. Both the heterocyclic rings are associated with diverse biological actions, therefore considered as an important scaffold for the design of molecules of pharmaceutical interest. Aim: To synthesize and evaluate the in vivo anti-inflammatory activity of few coumrain and flavone derivatives containing 1,4 dioxane ring system. Materials and methods: Coumarin derivatives (3a-d) were synthesized by reacting 7,8 dihydroxy coumarin (2a) and its 4-methyl derivative (2b) with epichlorohydrin/ethylene dibromide. The flavone derivatives (10a-d) were prepared by using quercetin and 3,4 dihydroxy flavones. Compounds of both the series were also evaluated for their anti-inflammatory, analgesic activity and ulcerogenicity in animal models by reported methods. Results and Discussion: The structures of all newly synthesized compounds were confirmed with the help of IR, 1H NMR, 13C NMR and Mass spectral studies. Elemental analyses data for each element analyzed (C, H, N) was found to be within acceptable range of ±0.4 %. Flavone derivatives, but in particular quercetin containing 1,4 dioxane ring system (10d) showed better anti-inflammatory and analgesic activity along with reduced gastrointestinal toxicity as compared to other synthesized compounds. The results of anti-inflammatory and analgesic activities of both the series are comparable with the positive control, diclofenac. Conclusion: Compound 10d, a quercetin derivative, emerged as a lead molecule which exhibited potent anti-inflammatory and analgesic activity with significant reduced gastric toxicity.Keywords: analgesic, anti-inflammatory, 1, 4 dioxane, coumarin, flavone
Procedia PDF Downloads 327599 Aquatic Environmental Effects of Black Shale in Eastern Kentucky through the Measurement of Chemical and Physical Properties
Authors: Mitchell T. Grothaus, Cory Grigsby, Timothy S. Hare
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This study aims to determine if there is a relationship between elevated cancer risks in eastern Kentucky and the environmental effects of black shale. Previous research shows that black shale formations, such as those in eastern Kentucky contain high levels of toxic elements including arsenic and radon compared to average rocks and sediment. Similarly, the population of eastern Kentucky has higher rates of many health conditions, including lung cancer and cardiovascular disease, than surrounding regions. These poor health outcomes are typically explained in relation to social, economic, behavioral, and healthcare factors. The rates of many conditions, however, have not decreased as these factors improve with regional development. Black shale is known to affect environmental conditions such as by increasing radiation levels and heavy metal toxicity. We are mapping the effects of black shale through monitoring radiation, microbes, and chemical standards of water sources. In this presentation, we report on our measuring pH, dissolved oxygen, total dissolved solids, conductivity, temperature, and discharge and comparison with water quality standards from the Kentucky Department for Environmental Protection. The conditions of water sources combined with an environmental survey of the surrounding areas provide a greater understanding of why the people in eastern Kentucky face the current health issues.Keywords: black shale, eastern Kentucky, environmental impact, water quality
Procedia PDF Downloads 164598 Estimation of Bio-Kinetic Coefficients for Treatment of Brewery Wastewater
Authors: Abimbola M. Enitan, J. Adeyemo
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Anaerobic modeling is a useful tool to describe and simulate the condition and behaviour of anaerobic treatment units for better effluent quality and biogas generation. The present investigation deals with the anaerobic treatment of brewery wastewater with varying organic loads. The chemical oxygen demand (COD) and total suspended solids (TSS) of the influent and effluent of the bioreactor were determined at various retention times to generate data for kinetic coefficients. The bio-kinetic coefficients in the modified Stover–Kincannon kinetic and methane generation models were determined to study the performance of anaerobic digestion process. At steady-state, the determination of the kinetic coefficient (K), the endogenous decay coefficient (Kd), the maximum growth rate of microorganisms (µmax), the growth yield coefficient (Y), ultimate methane yield (Bo), maximum utilization rate constant Umax and the saturation constant (KB) in the model were calculated to be 0.046 g/g COD, 0.083 (dˉ¹), 0.117 (d-¹), 0.357 g/g, 0.516 (L CH4/gCODadded), 18.51 (g/L/day) and 13.64 (g/L/day) respectively. The outcome of this study will help in simulation of anaerobic model to predict usable methane and good effluent quality during the treatment of industrial wastewater. Thus, this will protect the environment, conserve natural resources, saves time and reduce cost incur by the industries for the discharge of untreated or partially treated wastewater. It will also contribute to a sustainable long-term clean development mechanism for the optimization of the methane produced from anaerobic degradation of waste in a close system.Keywords: brewery wastewater, methane generation model, environment, anaerobic modeling
Procedia PDF Downloads 270597 The Mechanism Study of Degradative Solvent Extraction of Biomass by Liquid Membrane-Fourier Transform Infrared Spectroscopy
Authors: W. Ketren, J. Wannapeera, Z. Heishun, A. Ryuichi, K. Toshiteru, M. Kouichi, O. Hideaki
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Degradative solvent extraction is the method developed for biomass upgrading by dewatering and fractionation of biomass under the mild condition. However, the conversion mechanism of the degradative solvent extraction method has not been fully understood so far. The rice straw was treated in 1-methylnaphthalene (1-MN) at a different solvent-treatment temperature varied from 250 to 350 oC with the residence time for 60 min. The liquid membrane-Fourier Transform Infrared Spectroscopy (FTIR) technique is applied to study the processing mechanism in-depth without separation of the solvent. It has been found that the strength of the oxygen-hydrogen stretching (3600-3100 cm-1) decreased slightly with increasing temperature in the range of 300-350 oC. The decrease of the hydroxyl group in the solvent soluble suggested dehydration reaction taking place between 300 and 350 oC. FTIR spectra in the carbonyl stretching region (1800-1600 cm-1) revealed the presence of esters groups, carboxylic acid and ketonic groups in the solvent-soluble of biomass. The carboxylic acid increased in the range of 200 to 250 oC and then decreased. The prevailing of aromatic groups showed that the aromatization took place during extraction at above 250 oC. From 300 to 350 oC, the carbonyl functional groups in the solvent-soluble noticeably decreased. The removal of the carboxylic acid and the decrease of esters into the form of carbon dioxide indicated that the decarboxylation reaction occurred during the extraction process.Keywords: biomass waste, degradative solvent extraction, mechanism, upgrading
Procedia PDF Downloads 285596 Heat Treatment of Additively Manufactured Hybrid Rocket Fuel Grains
Authors: Jim J. Catina, Jackee M. Gwynn, Jin S. Kang
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Additive manufacturing (AM) for hybrid rocket engines is becoming increasingly attractive due to its ability to create complex grain configurations with improved regression rates when compared to cast grains. However, the presence of microvoids in parts produced through the additive manufacturing method of Fused Deposition Modeling (FDM) results in a lower fuel density and is believed to cause a decrease in regression rate compared to ideal performance. In this experiment, FDM was used to create hybrid rocket fuel grains with a star configuration composed of acrylonitrile butadiene styrene (ABS). Testing was completed to determine the effect of heat treatment as a post-processing method to improve the combustion performance of hybrid rocket fuel grains manufactured by FDM. For control, three ABS star configuration grains were printed using FDM and hot fired using gaseous oxygen (GOX) as the oxidizer. Parameters such as thrust and mass flow rate were measured. Three identical grains were then heat treated to varying degrees and hot fired under the same conditions as the control grains. This paper will quantitatively describe the amount of improvement in engine performance as a result of heat treatment of the AM hybrid fuel grain. Engine performance is measured in this paper by specific impulse, which is determined from the thrust measurements collected in testing.Keywords: acrylonitrile butadiene styrene, additive manufacturing, fused deposition modeling, heat treatment
Procedia PDF Downloads 117595 Catalytic Thermodynamics of Nanocluster Adsorbates from Informational Statistical Mechanics
Authors: Forrest Kaatz, Adhemar Bultheel
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We use an informational statistical mechanics approach to study the catalytic thermodynamics of platinum and palladium cuboctahedral nanoclusters. Nanoclusters and their adatoms are viewed as chemical graphs with a nearest neighbor adjacency matrix. We use the Morse potential to determine bond energies between cluster atoms in a coordination type calculation. We use adsorbate energies calculated from density functional theory (DFT) to study the adatom effects on the thermodynamic quantities, which are derived from a Hamiltonian. Oxygen radical and molecular adsorbates are studied on platinum clusters and hydrogen on palladium clusters. We calculate the entropy, free energy, and total energy as the coverage of adsorbates increases from bridge and hollow sites on the surface. Thermodynamic behavior versus adatom coverage is related to the structural distribution of adatoms on the nanocluster surfaces. The thermodynamic functions are characterized using a simple adsorption model, with linear trends as the coverage of adatoms increases. The data exhibits size effects for the measured thermodynamic properties with cluster diameters between 2 and 5 nm. Entropy and enthalpy calculations of Pt-O2 compare well with previous theoretical data for Pt(111)-O2, and our Pd-H results show similar trends as experimental measurements for Pd-H2 nanoclusters. Our methods are general and may be applied to wide variety of nanocluster adsorbate systems.Keywords: catalytic thermodynamics, palladium nanocluster absorbates, platinum nanocluster absorbates, statistical mechanics
Procedia PDF Downloads 166594 Improving Lutein Bioavailability by Nanotechnology Applications
Authors: Hulya Ilyasoglu Buyukkestelli, Sedef Nehir El
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Lutein is a member of xanthophyll group of carotenoids found in fruits and vegetables. Lutein accumulates in the macula region of the retina and known as macular pigment which absorbs damaging light in the blue wavelengths. The presence of lutein in retina has been related to decreased risk of two common eye diseases, age-related macular degeneration, and cataract. Being a strong antioxidant, it may also have effects on prevention some types of cancer, cardiovascular disease, cognitive dysfunction. Humans are not capable of synthesizing lutein de novo; therefore it must be provided naturally by the diet, fortified foods, and beverages or nutritional supplement. However, poor bioavailability and physicochemical stability limit its usage in the food industry. Poor solubility in digestive fluids and sensitivity to heat, light, and oxygen are both affect the stability and bioavailability of lutein. In this context, new technologies, delivery systems and formulations have been applied to improve stability and solubility of lutein. Nanotechnology, including nanoemulsion, nanocrystal, nanoencapsulation technology and microencapsulation by complex coacervation, spray drying are promising ways of increasing solubilization of lutein and stability of it in different conditions. Bioavailability of lutein is also dependent on formulations used, starch formulations and milk proteins, especially sodium caseinate are found effective in improving the bioavailability of lutein. Designing foods with highly bioavailable and stabile lutein needs knowledge about current technologies, formulations, and further needs. This review provides an overview of the new technologies and formulations used to improve bioavailability of lutein and also gives a future outlook to food researches.Keywords: bioavailability, formulation, lutein, nanotechnology
Procedia PDF Downloads 380593 Starchy Wastewater as Raw Material for Biohydrogen Production by Dark Fermentation: A Review
Authors: Tami A. Ulhiza, Noor I. M. Puad, Azlin S. Azmi, Mohd. I. A. Malek
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High amount of chemical oxygen demand (COD) in starchy waste can be harmful to the environment. In common practice, starch processing wastewater is discharged to the river without proper treatment. However, starchy waste still contains complex sugars and organic acids. By the right pretreatment method, the complex sugar can be hydrolyzed into more readily digestible sugars which can be utilized to be converted into more valuable products. At the same time, the global demand of energy is inevitable. The continuous usage of fossil fuel as the main source of energy can lead to energy scarcity. Hydrogen is a renewable form of energy which can be an alternative energy in the future. Moreover, hydrogen is clean and carries the highest energy compared to other fuels. Biohydrogen produced from waste has significant advantages over chemical methods. One of the major problems in biohydrogen production is the raw material cost. The carbohydrate-rich starchy wastes such as tapioca, maize, wheat, potato, and sago wastes is a promising candidate to be used as a substrate in producing biohydrogen. The utilization of those wastes for biohydrogen production can provide cheap energy generation with simultaneous waste treatment. Therefore this paper aims to review variety source of starchy wastes that has been widely used to synthesize biohydrogen. The scope includes the source of waste, the performance in yielding hydrogen, the pretreatment method and the type of culture that is suitable for starchy waste.Keywords: biohydrogen, dark fermentation, renewable energy, starchy waste
Procedia PDF Downloads 223592 COVID-19: The Cause or the Confounder
Authors: Praveenkumar Natarajan
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A 59-year-old male with no known co-morbidities was admitted to a private hospital for complaints of fever and cough and was diagnosed to haveCOVID-19. CT of the thorax revealed the involvement of 50% of the lungs. Screening ECG and ECHO were normal. The patient was treated with oxygen therapy and drugs and was discharged after 12 days of admission. Post-discharge, the patient remained symptom-free and continued his work. After one month, the patient developed a fever for three days, for which he took antipyretics. Subsequently, the patient developed sudden onset breathlessness, which rapidly progressed to grade 4 NYHA, and developed a cough as well. Suspecting COVID-19 reinfection, the patient visited a nearby hospital, where COVID–19 rt-PCR swabs turned out to be positive, and was referred to our hospital. On receiving, the patient had diffuse lung crepitations and a diastolic murmur in the neo-aortic area. CT thorax revealed pulmonary edema with areas of consolidation. ECHO revealed vegetation on the aortic valve with severe aortic regurgitation. Blood cultures were taken, which revealed the growth of Enterococcus faecalis. The diagnosis of infective endocarditis was made, and the patient was started on appropriate treatment. COVID–19 has effects on various systems, including the cardiovascular system. Even though infective endocarditis is common in the elderly with valvular heart disease, this patient had developed infective endocarditis in an apparently normal aortic valve. Infective endocarditis and COVID–19 can have similar presentations leading to diagnostic difficulties. COVID–19, affecting the heart valves causing valvulitis and predisposing them to the development of infective endocarditis, is also an area to be explored.Keywords: aortic regurgitation, COVID-19, infective endocarditis, valvulitis
Procedia PDF Downloads 135591 Cost Effective Intraoperative Mri for Cranial and Spinal Cases Using Pre-Existing Three Side Open Mri-Adjacent to Operation Theater = Since-2005
Authors: V. K. Tewari, M. Hussain, H. K. D.Gupta
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Aims/Background: The existing Intraoperative-MRI(IMRI) of developed countries is too costly to be utilized in any developing country. We have used the preexisting 3-side open 0.2-tesla MRI for IMRI in India so that the maximum benefit of the goal of IMRI is attained with cost effective state of the art surgeries. Material/Methods: We have operated 36-cases since 13thNov2005 via IMRI to till date. The table of MRI is used as an operating table which can be taken to the P3 level and as and when we require MRI to be done then the table can slide to P1 level so that the intraoperative monitoring can be done. The oxygen/nitrous tubes were taken out from vent made in the wall of the MRI room to outside. The small handy Boyel’s trolley was taken inside the MRI room with a small monitor. Anesthesia is been given in the MRI room itself. Usual skin markings were given with the help of scout MRI fields so the preciseness is increased. Craniotomy flap raised or the laminectomy and the dura opened in the similar fashion by same instruments as for the non IMRI case. Now corticectomy is planned after the T1 contrast image to localize and minimize the cortical resection. Staged and multiple P3 to P1 position and vice versa is planned respectively so that the resection is optimized to around 0.5 mm for radiotherapy. Immediate preclosure hematoma and edemas can be differentiated and cared for it. Results: Same MRI images as compared to highly expensive MRI of western world are achieved. Conclusion: 0.2 tesla Intraoperative MRI can be used for operative work for cranial and spinal cases easily with highly cost effectiveness.Keywords: intraoperative MRI, 0.2 tesla intraoperative MRI, cost effective intraoperative MRI, medical and health sciences
Procedia PDF Downloads 454590 Cissampelos capensis Rhizome Extract Induces Intracellular ROS Production, Capacitation, and DNA Fragmentation in Human Spermatozoa
Authors: S. Shalaweh, P. Bouic, F. Weitz, R. Henkel
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More than 3000 plants of notable phyto-therapeutic value grow in South Africa; these include Cissampelos capensis, commonly known in Afrikaans as dawidjie or dawidjiewortel. C. capensis is the most significant and popular medicinal plant used by the Khoisan as well as other rural groups in the Western region of South Africa. Its rhizomes are traditionally used to treat male fertility problems. Yet, no studies have investigated the effects of this plant or its extracts on human spermatozoa. Therefore, this study aimed at investigating the effects of C. capensis rhizome extract (CRE) fractions on ejaculated human spermatozoa in vitro. Spermatozoa from a total of 77 semen samples were washed with human tubular fluid medium supplemented with bovine serum albumin (HTF-BSA) and incubated for 2 hourswith 20 µg/ml progesterone (P4) followed by incubation with different concentrations (0, 0.05, 0.5, 5, 50, 200 µg/ml) of fractionated CRE (F1=0% MeOH, F2=30% MeOH, F3=60% MeOH and F4=100% MeOH) for 1.5 hours at 37°C. A sample without addition of CRE fractions served as control. Samples were analyzed for sperm motility, reactive oxygen species (ROS), DNA-fragmentation, acrosome reaction and capacitation. Results showed that F1 resulted in significantly higher values for ROS, capacitation and hyper-activation compared to F2, F3, and F4 with P4-stimulated samples generally having higher values. No significant effect was found for the other parameters. In conclusion, alkaloids present in F1 of CRE appear to have triggered sperm intrinsic ROS production leading to sperm capacitation and acrosome reaction induced by P4.Keywords: capacitaion, acrosome reaction, DNA fragmentation, ROS
Procedia PDF Downloads 308589 Energetics of Photosynthesis with Respect to the Environment and Recently Reported New Balanced Chemical Equation
Authors: Suprit Pradhan, Sushil Pradhan
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Photosynthesis is a physiological process where green plants prepare their food from carbon dioxide from the atmosphere and water being absorbed from the soil in presence of sun light and chlorophyll. From this definition it is clear that four reactants (Carbon Dioxide, Water, Light and Chlorophyll) are essential for the process to proceed and the product is a sugar or carbohydrate ultimately stored as starch. The entire process has “Light Reaction” (Photochemical) and “Dark Reaction” (Biochemical). Biochemical reactions are very much complicated being catalysed by various enzymes and the path of carbon is known as “Calvin Cycle” according to the name of its discover. The overall reaction which is now universally accepted can be explained like this. Six molecules of carbon dioxide react with twelve molecules of water in presence of chlorophyll and sun light to give only one molecule of sugar (Carbohydrate) six molecules of water and six molecules of oxygen is being evolved in gaseous form. This is the accepted equation and also chemically balanced. However while teaching the subject the author came across a new balanced equation from among the students who happened to be the daughter of the author. In the new balanced equation in place of twelve water molecules in the reactant side seven molecules can be expressed and accordingly in place of six molecules of water in the product side only one molecule of water is produced. The energetics of the photosynthesis as related to the environment and the newly reported balanced chemical equation has been discussed in detail in the present research paper presentation in this international conference on energy, environmental and chemical engineering.Keywords: biochemistry, enzyme , isotope, photosynthesis
Procedia PDF Downloads 511588 Catalytic Pyrolysis of Barley Straw for the Production of Fuels and Chemicals
Authors: Funda Ates
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Primary energy sources, such as petroleum, coal and natural gas are principle responsible of world’s energy consumption. However, the rapid worldwide increase in the depletion of these energy sources is remarkable. In addition to this, they have damaging environmentally effect. Renewable energy sources are capable of providing a considerable fraction of World energy demand in this century. Biomass is one of the most abundant and utilized sources of renewable energy in the world. It can be converted into commercial fuels, suitable to substitute for fossil fuels. A high number of biomass types can be converted through thermochemical processes into solid, liquid or gaseous fuels. Pyrolysis is the thermal decomposition of biomass in the absence of air or oxygen. In this study, barley straw has been investigated as an alternative feedstock to obtain fuels and chemicals via pyrolysis in fixed-bed reactor. The influence of pyrolysis temperature in the range 450–750 °C as well as the catalyst effects on the products was investigated and the obtained results were compared. The results indicated that a maximum oil yield of 20.4% was obtained at a moderate temperature of 550 °C. Oil yield decreased by using catalyst. Pyrolysis oils were examined by using instrumental analysis and GC/MS. Analyses revealed that the pyrolysis oils were chemically very heterogeneous at all temperatures. It was determined that the most abundant compounds composing the bio-oil were phenolics. Catalyst decreased the reaction temperature. Most of the components obtained using a catalyst at moderate temperatures was close to those obtained at high temperatures without using a catalyst. Moreover, the use of a catalyst also decreased the amount of oxygenated compounds produced.Keywords: Barley straw, pyrolysis, catalyst, phenolics
Procedia PDF Downloads 225587 Compositional Dependence of Hydroxylated Indium-Oxide on the Reaction Rate of CO2/H2 Reduction
Authors: Joel Y. Y. Loh, Geoffrey A. Ozin, Charles A. Mims, Nazir P. Kherani
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A major goal in the emerging field of solar fuels is to realize an ‘artificial leaf’ – a material that converts light energy in the form of solar photons into chemical energy – using CO2 as a feedstock to generate useful chemical species. Enabling this technology will allow the greenhouse gas, CO2, emitted from energy and manufacturing production exhaust streams to be converted into valuable solar fuels or chemical products. Indium Oxide (In2O3) with surface hydroxyl (OH) groups have been shown to reduce CO2 in the presence of H2 to CO with a reaction rate of 15 μmol gcat−1 h−1. The likely mechanism is via a Frustrated Lewis Pair sites heterolytically splitting H2 to be absorbed and form protonic and hydric sites that can dissociate CO2. In this study, we investigate the dependence of oxygen composition of In2O3 on the CO2 reduction rate. In2O3-x films on quartz fiber paper were DC sputtered with an Indium target and varying O2/Ar plasma mixture. OH surface groups were then introduced by immersing the In2O3-x samples in KOH. We show that hydroxylated In2O3-x reduces more CO2 than non-hydroxylated groups and that a hydroxylated and higher O2/Ar ratio sputtered In2O3-x has a higher reaction rate of 45 μmol gcat-1 h-1. We show by electrical resistivity-temperature curves that H2 is adsorbed onto the surface of In2O3 whereas CO2 itself does not affect the indium oxide surface. We also present activation and ionization energy levels of the hydroxylated In2O3-x under vacuum, CO2 and H2 atmosphere conditions.Keywords: solar fuels, photocatalysis, indium oxide nanoparticles, carbon dioxide
Procedia PDF Downloads 240586 Microstructure and Mechanical Properties of Nb: Si: (a-C) Thin Films Prepared Using Balanced Magnetron Sputtering System
Authors: Sara Khamseh, Elahe Sharifi
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321 alloy steel is austenitic stainless steel with high oxidation resistance and is commonly used to fabricate heat exchangers and steam generators. However, the low hardness and weak tribological performance can cause dangerous failures during industrial operations. The well-designed protective coatings on 321 alloy steel surfaces with high hardness and good tribological performance can guarantee their safe applications. The surface protection of metal substrates using protective coatings showed high efficiency in prevailing these problems. Carbon-based multicomponent coatings, such as metal-added amorphous carbon coatings, are crucially necessary because of their remarkable mechanical and tribological performances. In the current study, (Nb: Si: a-C) multicomponent coatings (a-C: amorphous carbon) were coated on 321 alloys using a balanced magnetron (BM) sputtering system at room temperature. The effects of the Si/Nb ratio on microstructure, mechanical and tribological characteristics of (Nb: Si: a-C) composite coatings were investigated. The XRD and Raman analysis results showed that the coatings formed a composite structure of cubic diamond (C-D), NbC, and graphite-like carbon (GLC). The NbC phase's abundance decreased when the C-D phase's affluence increased with an increasing Si/Nb ratio. The coatings' indentation hardness and plasticity index (H³/E² ratio) increased with an increasing Si/Nb ratio. The better mechanical properties of the coatings with higher Si content can be attributed to the higher cubic diamond (C-D) content. The cubic diamond (C-D) is a challenging phase and can positively affect the mechanical performance of the coatings. It is well documented that in hard protective coatings, Si encourages amorphization. In addition, THE studies showed that Nb and Mo can act as a catalyst for nucleation and growth of hard cubic (C-D) and hexagonal (H-D) diamond phases in a-C coatings. In the current study, it seems that fully arranged nanocomposite coatings contain hard C-D and NbC phases that embedded in the amorphous carbon (GLC) phase is formed. This unique structure decreased grain boundary density and defects and resulted in high hardness and H³/E² ratio. Moreover, the COF and wear rate of the coatings decreased with increasing Si/Nb ratio. This can be attributed to the good mechanical properties of the coatings and the formation of graphite-like carbon (GLC) structure with lamellae arrangement in the coatings. The complex and self-lubricant coatings are successfully formed on the surface of 321 alloys. The results of the present study clarified that Si addition to (Nb: a-C) coatings improve the mechanical and tribological performance of the coatings on 321 alloy.Keywords: COF, mechanical properties, microstructure, (Nb: Si: a-C) coatings, Wear rate
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