Search results for: granular activated carbon
3223 Study on Carbon Nanostructures Influence on Changes in Static Friction Forces
Authors: Rafał Urbaniak, Robert Kłosowiak, Michał Ciałkowski, Jarosław Bartoszewicz
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The Chair of Thermal Engineering at Poznan University of Technology has been conducted research works on the possibilities of using carbon nanostructures in energy and mechanics applications for a couple of years. Those studies have provided results in a form of co-operation with foreign research centres, numerous publications and patent applications. Authors of this paper have studied the influence of multi-walled carbon nanostructures on changes in static friction arising when steel surfaces were moved. Tests were made using the original test stand consisting of automatically controlled inclined plane driven by precise stepper motors. Computer program created in the LabView environment was responsible for monitoring of the stand operation, accuracy of measurements and archiving the obtained results. Such a solution enabled to obtain high accuracy and repeatability of all conducted experiments. Tests and analysis of the obtained results allowed us to determine how additional layers of carbon nanostructures influenced on changes of static friction coefficients. At the same time, we analyzed the potential possibilities of applying nanostructures under consideration in mechanics.Keywords: carbon nanotubes, static friction, dynamic friction
Procedia PDF Downloads 3103222 A Comparative Analysis of Carbon Footprints of Households in Different Housing Types and Seasons
Authors: Taehyun Kim
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As a result of rapid urbanization, energy demands for lighting, heating and cooling of households have been concentrated in metropolitan areas. The energy resources for housing in urban areas are dominantly fossil fuel whose uses contribute to increase cost of living and carbon dioxide (CO2) emission. To achieve environmentally and economically sustainable residential development, it is important to know how energy use and cost of living can be reduced by planning and design. The purpose of this study is to examine which type of building requires less energy for housing. To do so, carbon footprint (CF) quiz survey was employed which estimates the amount of carbon dioxide required to support households’ consumption of energy uses for housing. The housing carbon footprints (HCF) of 500 households of Seoul, Korea in summer and winter were estimated and compared in three major types of housing: single-family (detached), row-house and apartment. In addition, its differences of HCF were estimated between tower and flat type of apartment. The results of T-test and analysis of variance (ANOVA) provide statistical evidence that housing type is related to housing energy use. Average HCF of detached house was higher than other housing types. Between two types of apartment, tower type shows higher HCF than flat type in winter. These findings may provide new perspectives on CF application in sustainable architecture and urban design.Keywords: analysis of variance, carbon footprint, energy use, housing type
Procedia PDF Downloads 4973221 Growth Model and Properties of a 3D Carbon Aerogel
Authors: J. Marx, D. Smazna, R. Adelung, B. Fiedler
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Aerographite is a 3D interconnected carbon foam. Its tetrapodal morphology is based on the zinc oxide (ZnO) template structure, which is replicated in the chemical vapour deposition (CVD) into a hollow carbon structure. This replication process is analyzed in ex-situ studies via interrupted synthesis and the observation of the reaction progress by using scanning electron (SEM), transmission electron microscopy (TEM) and Raman spectroscopy techniques. Based on the epitaxial growth process, with a layer-by-layer growth behaviour of the wall thickness or number of layers and the catalytical graphitization of the deposited amorphous carbon into graphitic carbon by zinc, a growth model is created. The properties of aerographite, such as the electrical conductivity is dependent on the graphitization and number of layer (wall thickness). Wall thicknesses between 3 nm and 22 nm are achieved by a controlled stepwise reduction of the synthesis time on the basis of the developed growth model, and by a further thermal treatment at 1800 °C the graphitization of the presented carbon foam is modified. The variation of the wall thickness leads to an optimum defect density (ID/IG ratio) and the graphitization to an improvement in the electrical conductivity. Furthermore, a metallic conducting behaviour of untreated and 1800 °C treated aerographite can be observed. Due to these structural and defective modifications, a fundamental structural-property equation for the description of their influences on the electrical conductivity is developed.Keywords: electrical conductivity, electron microscopy (SEM/TEM), graphitization, wall thickness
Procedia PDF Downloads 1483220 Vibration Control of a Functionally Graded Carbon Nanotube-Reinforced Composites Beam Resting on Elastic Foundation
Authors: Gholamhosein Khosravi, Mohammad Azadi, Hamidreza Ghezavati
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In this paper, vibration of a nonlinear composite beam is analyzed and then an active controller is used to control the vibrations of the system. The beam is resting on a Winkler-Pasternak elastic foundation. The composite beam is reinforced by single walled carbon nanotubes. Using the rule of mixture, the material properties of functionally graded carbon nanotube-reinforced composites (FG-CNTRCs) are determined. The beam is cantilever and the free end of the beam is under follower force. Piezoelectric layers are attached to the both sides of the beam to control vibrations as sensors and actuators. The governing equations of the FG-CNTRC beam are derived based on Euler-Bernoulli beam theory Lagrange- Rayleigh-Ritz method. The simulation results are presented and the effects of some parameters on stability of the beam are analyzed.Keywords: carbon nanotubes, vibration control, piezoelectric layers, elastic foundation
Procedia PDF Downloads 2623219 Comparative Histological, Immunohistochemical and Biochemical Study on the Effect of Vit. C, Vit. E, Gallic Acid and Silymarin on Carbon Tetrachloride Model of Liver Fibrosis in Rats
Authors: Safaa S. Hassan, Mohammed H. Elbakry, Safwat A. Mangoura, Zainab M. Omar
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Background: Liver fibrosis is the main reason for increased mortality in chronic liver disease. It has no standard treatment. Antioxidants from a variety of sources are capable of slowing or preventing oxidation of other molecules. Aim: to evaluate the hepatoprotective effect of vit. C, vit. E and gallic acid in comparison to silymarin in the rat model of carbon tetrachloride induced liver fibrosis and their possible mechanisms of action. Material& Methods: A total number of 60 adult male albino rats 160-200gm were divided into six equal groups; received subcutaneous (s.c) injection for 8 weeks. Group I: as control. Group II: received 1.5 mL/kg of CCL4 .Group III: CCL4 and co- treatment with silymarin 100mg/kg p.o. daily. Group IV: CCL4 and co-treatment with vit. C 50mg/kg p.o. daily. Group V: CCL4 and co-treatment with vit. E 200mg/kg. p.o. Group VI: CCL4 and co-treatment with Gallic acid 100mg/kg. p.o. daily. Liver was processed for histological and immunohistochemical examination. Levels of AST, ALT, ALP, reduced GSH, MDA, SOD and hydroxyproline concentration were measured and evaluated statistically. Results: Light and electron microscopic examination of liver of group II exhibited foci of altered cells with dense nuclei and vacuolated, granular cytoplasm, mononuclear cell infiltration in portal areas, profuse collagen fiber deposits were found around portal tract, more intense staining α-SMA-positive cells occupied most of the liver fibrosis tissue, electron lucent areas in the cytoplasm of the hepatocytes, margination of nuclear chromatin. Treatment by any of the antioxidants variably reduced the hepatic structural changes induced by CCL4. Biochemical analysis showed that carbon tetrachloride significantly increased the levels of serum AST, ALT, ALP, hepatic malondialdehyde and hydroxyproline content. Moreover, it decreased the activities of superoxide dismutase and glutathione. Treatment with silymarin, gallic acid, vit. C and vit. E decreased significantly the AST, ALT, and ALP levels in plasma, MDA and hydroxyproline and increased the activities of SOD and glutathione in liver tissue. The effect of administration of CCl4 was improved with the used antioxidants in variable degrees. The most efficient antioxidant was silymarin followed by gallic acid and vit. C then vit. E. It is possibly due to their antioxidant effect, free radical scavenging properties and the reduction of oxidant dependent activation and proliferation of HSCs. Conclusion: So these antioxidants can be a promising drugs candidate for ameliorating liver fibrosis better than the use of the drugs and their side effects.Keywords: antioxidant, ccl4, gallic acid, liver fibrosis
Procedia PDF Downloads 2693218 Potential Role of Arbuscular Mycorrhizal (AM) Fungi in CO₂-Sequestration During Bipartite Interaction with Host Plant Oryza Sativa
Authors: Sadhana Shukla, Pushplata Singh, Nidhi Didwania
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Arbuscular mycorrhizal (AM) fungi are a highly advantageous and versatile group of fungi that significantly contribute to the formation of soil organic matter by creating a demand for plant carbon (C) and distributing it through below-ground hyphal biomass, regardless of their substantial contribution in enhancing net primary productivity and accumulating additional photosynthetic fixed C in the soil. The genetic role of AM fungi in carbon cycling is largely unexplored. In our study, we propose that AM fungi significantly interact with the soil, particularly: the provision of photosynthates by plants. We have studied the expression of AM fungi genes involved in CO₂ sequestration during host-plant interaction was investigated by qPCR studies. We selected Rhizophagus proliferus (AM fungi) and Oryza sativa (Rice) (inoculated with or without 200ppg AMF inoculums per plant) and investigated the effect of AM fungi on soil organic carbon (SOC) and rice growth under field conditions. Results thus provided faster SOC turnover, 35% increased nutrient uptake in plants and pronounced hyphal biomass of AM fungi which enhanced soil carbon storage by 15% in comparison to uninoculated plants. This study will offer a foundation for delving into various carbon-soil studies while also advancing our comprehension of the relationship between AM fungi and the sustainability of agricultural ecosystems.Keywords: arbuscular mycorrhizal (AM) fungi, carbon sequestration, gene expression, soil health, plant development.
Procedia PDF Downloads 683217 Rapid Assessment the Ability of Forest Vegetation in Kulonprogo to Store Carbon Using Multispectral Satellite Imagery and Vegetation Index
Authors: Ima Rahmawati, Nur Hafizul Kalam
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Development of industrial and economic sectors in various countries very rapidly caused raising the greenhouse gas (GHG) emissions. Greenhouse gases are dominated by carbon dioxide (CO2) and methane (CH4) in the atmosphere that make the surface temperature of the earth always increase. The increasing gases caused by incomplete combustion of fossil fuels such as petroleum and coals and also high rate of deforestation. Yogyakarta Special Province which every year always become tourist destination, has a great potency in increasing of greenhouse gas emissions mainly from the incomplete combustion. One of effort to reduce the concentration of gases in the atmosphere is keeping and empowering the existing forests in the Province of Yogyakarta, especially forest in Kulonprogro is to be maintained the greenness so that it can absorb and store carbon maximally. Remote sensing technology can be used to determine the ability of forests to absorb carbon and it is connected to the density of vegetation. The purpose of this study is to determine the density of the biomass of forest vegetation and determine the ability of forests to store carbon through Photo-interpretation and Geographic Information System approach. Remote sensing imagery that used in this study is LANDSAT 8 OLI year 2015 recording. LANDSAT 8 OLI imagery has 30 meters spatial resolution for multispectral bands and it can give general overview the condition of the carbon stored from every density of existing vegetation. The method is the transformation of vegetation index combined with allometric calculation of field data then doing regression analysis. The results are model maps of density and capability level of forest vegetation in Kulonprogro, Yogyakarta in storing carbon.Keywords: remote sensing, carbon, kulonprogo, forest vegetation, vegetation index
Procedia PDF Downloads 3903216 Carbon Dioxide Capture and Utilization by Using Seawater-Based Industrial Wastewater and Alkanolamine Absorbents
Authors: Dongwoo Kang, Yunsung Yoo, Injun Kim, Jongin Lee, Jinwon Park
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Since industrial revolution, energy usage by human-beings has been drastically increased resulting in the enormous emissions of carbon dioxide into the atmosphere. High concentration of carbon dioxide is well recognized as the main reason for the climate change by breaking the heat equilibrium of the earth. In order to decrease the amount of carbon dioxide emission, lots of technologies have been developed. One of the methods is to capture carbon dioxide after combustion process using liquid type absorbents. However, for some nations, captured carbon dioxide cannot be treated and stored properly due to their geological structures. Also, captured carbon dioxide can be leaked out when crust activities are active. Hence, the method to convert carbon dioxide as stable and useful products were developed. It is usually called CCU, that is, Carbon Capture and Utilization. There are several ways to convert carbon dioxide into useful substances. For example, carbon dioxide can be converted and used as fuels such as diesel, plastics, and polymers. However, these types of technologies require lots of energy to make stable carbon dioxide into a reactive one. Hence, converting it into metal carbonates salts have been studied widely. When carbon dioxide is captured by alkanolamine-based liquid absorbents, it exists as ionic forms such as carbonate, carbamate, and bicarbonate. When adequate metal ions are added, metal carbonate salt can be produced by ionic reaction with fast reaction kinetics. However, finding metal sources can be one of the problems for this method to be commercialized. If natural resources such as calcium oxide were used to supply calcium ions, it is not thought to have the economic feasibility to use natural resources to treat carbon dioxide. In this research, high concentrated industrial wastewater produced from refined salt production facility have been used as metal supplying source, especially for calcium cations. To ensure purity of final products, calcium ions were selectively separated in the form of gypsum dihydrate. After that, carbon dioxide is captured using alkanolamine-based absorbents making carbon dioxide into reactive ionic form. And then, high purity calcium carbonate salt was produced. The existence of calcium carbonate was confirmed by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) images. Also, carbon dioxide loading curves for absorption, conversion, and desorption were provided. Also, in order to investigate the possibility of the absorbent reuse, reabsorption experiments were performed either. Produced calcium carbonate as final products is seemed to have potential to be used in various industrial fields including cement and paper making industries and pharmaceutical engineering fields.Keywords: alkanolamine, calcium carbonate, climate change, seawater, industrial wastewater
Procedia PDF Downloads 1813215 Investigation of Wood Chips as Internal Carbon Source Supporting Denitrification Process in Domestic Wastewater Treatment
Authors: Ruth Lorivi, Jianzheng Li, John J. Ambuchi, Kaiwen Deng
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Nitrogen removal from wastewater is accomplished by nitrification and denitrification processes. Successful denitrification requires carbon, therefore, if placed after biochemical oxygen demand (BOD) and nitrification process, a carbon source has to be re-introduced into the water. To avoid adding a carbon source, denitrification is usually placed before BOD and nitrification processes. This process however involves recycling the nitrified effluent. In this study wood chips were used as internal carbon source which enabled placement of denitrification after BOD and nitrification process without effluent recycling. To investigate the efficiency of a wood packed aerobic-anaerobic baffled reactor on carbon and nutrients removal from domestic wastewater, a three compartment baffled reactor was presented. Each of the three compartments was packed with 329 g wood chips 1x1cm acting as an internal carbon source for denitrification. The proposed mode of operation was aerobic-anoxic-anaerobic (OAA) with no effluent recycling. The operating temperature, hydraulic retention time (HRT), dissolved oxygen (DO) and pH were 24 ± 2 ℃, 24 h, less than 4 mg/L and 7 ± 1 respectively. The removal efficiencies of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total nitrogen (TN) attained was 99, 87 and 83% respectively. TN removal rate was limited by nitrification as 97% of ammonia converted into nitrate and nitrite was denitrified. These results show that application of wood chips in wastewater treatment processes is an efficient internal carbon source.
Keywords: aerobic-anaerobic baffled reactor, denitrification, nitrification, wood chip
Procedia PDF Downloads 2903214 Resin-coated Controlled Release Fertilizer (CRF) for Oil Palm: Laboratory and Main Nursery Evaluation
Authors: Umar Adli Amran, Tan Choon Chek, Mohd Shahkhirat Norizan, Then Kek Hoe
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Controlled release fertilizer (CRF) enables a regulated nutrients release for more efficient plant uptake compared to the normal granular fertilizer. It reduces nutrients loss via surface run-off and leaching, hence promotes sustainable agriculture. Although the performance of CRF in providing consistent and timely nutrients supply is well known, its expensive price limits it usage in a large scale plantation. This study is conducted to evaluate the properties and performance of bio-based polyurethane (PU)-coated CRF via laboratory and oil palm main nursery trial. The CRF is produced by coating of a normal commercial compound granular fertilizer from FGV Fertiliser Sdn. Bhd., namely Felda 10 (10.5-8-20-3+0.5B), and designated as CRF FGV10. Based on laboratory evaluation, the CRF FGV10 can sustain nutrients release for more than 6 months. Vegetative growth parameters such as girth size, palm height, third frond length, and the total number of fronds produced were recorded. Besides that, dry biomass of the oil palm seedlings was also determined. From the evaluation, it is proved that at 50% reduction of nutrients application rate and for only two times application (T3), CRF FGV10 enabled the oil palm seedlings to achieve similar vegetative growth with the control samples (T1). It is also proven that only PU-coated CRF FGV10 had allowed the reduction of fertilizer rate and application rounds.Keywords: nutrition, oil palm seedlings, polyurethane, sustainable manuring, vegetative growth
Procedia PDF Downloads 543213 Tokenization of Blue Bonds to Scale Blue Carbon Projects
Authors: Rodrigo Buaiz Boabaid
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Tokenization of Blue Bonds is an emerging Green Finance tool that has the potential to scale Blue Carbon Projects to fight climate change. This innovative solution has a huge potential to democratize the green finance market and catalyze innovations in the climate change finance sector. Switzerland has emerged as a leader in the Green Finance space and is well-positioned to drive the adoption of Tokenization of Blue & Green Bonds. This unique approach has the potential to unlock new sources of capital and enable global investors to participate in the financing of sustainable blue carbon projects. By leveraging the power of blockchain technology, Tokenization of Blue Bonds can provide greater transparency, efficiency, and security in the investment process while also reducing transaction costs. Investments are in line with the highest regulations and designed according to the stringent legal framework and compliance standards set by Switzerland. The potential benefits of Tokenization of Blue Bonds are significant and could transform the way that sustainable projects are financed. By unlocking new sources of capital, this approach has the potential to accelerate the deployment of Blue Carbon projects and create new opportunities for investors to participate in the fight against climate change.Keywords: blue bonds, blue carbon, tokenization, green finance
Procedia PDF Downloads 763212 Effect of Carbon Nanotubes on Thermophysical Properties of Photothermal Fluid and Enhancement of Photothermal Deflection Signal
Authors: Muhammad Shafiq Ahmed, Sabastine Ezugwu
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Thermophysical properties of Carbon Tetrachloride (CCl₄), a photothermal fluid used frequently in Photothermal Deflection Spectroscopy (PDS), containing different volume fractions of single walled carbon nanotube (SWCNTs) and their effect on the amplitude of PDS signal are investigated. It is found that the presence of highly thermally conducting SWCNTs in CCl₄ enhances the heat transfer from heated sample to the adjoining photothermal fluid, resulting in an increase in the intensity of amplitude of PDS signal. With the increasing volume fraction of SWCNTs in CCl₄, the amplitude of PDS signal is nearly doubled for volume fraction fopt =3.7X10⁻³ %., after that the signal drops with a further increase in the fraction of SWCNTs. It is shown that the use of highly thermally conducting carbon nanotubes enhances the heat exchange coefficient between the heated sample surface and adjoining fluid, resulting to an enhancement of PDS signal and consequently the improvement in the sensitivity of PDS technique.Keywords: carbon nanotubes, heat transfer, nanofluid, photothermal deflection spectroscopy, thermophysical properties
Procedia PDF Downloads 1513211 Comparing Spontaneous Hydrolysis Rates of Activated Models of DNA and RNA
Authors: Mohamed S. Sasi, Adel M. Mlitan, Abdulfattah M. Alkherraz
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This research project aims to investigate difference in relative rates concerning phosphoryl transfer relevant to biological catalysis of DNA and RNA in the pH-independent reactions. Activated Models of DNA and RNA for alkyl-aryl phosphate diesters (with 4-nitrophenyl as a good leaving group) have successfully been prepared to gather kinetic parameters. Eyring plots for the pH–independent hydrolysis of 1 and 2 were established at different temperatures in the range 100–160 °C. These measurements have been used to provide a better estimate for the difference in relative rates between the reactivity of DNA and RNA cleavage. Eyring plot gave an extrapolated rate of kH2O = 1 × 10-10 s -1 for 1 (RNA model) and 2 (DNA model) at 25°C. Comparing the reactivity of RNA model and DNA model shows that the difference in relative rates in the pH-independent reactions is surprisingly very similar at 25°. This allows us to obtain chemical insights into how biological catalysts such as enzymes may have evolved to perform their current functions.Keywords: DNA and RNA models, relative rates, reactivity, phosphoryl transfe
Procedia PDF Downloads 4173210 Removal of Na₂SO₄ by Electro-Confinement on Nanoporous Carbon Membrane
Authors: Jing Ma, Guotong Qin
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We reported electro-confinement desalination (ECMD), a desalination method combining electric field effects and confinement effects using nanoporous carbon membranes as electrode. A carbon membrane with average pore size of 8.3 nm was prepared by organic sol-gel method. The precursor of support was prepared by curing porous phenol resin tube. Resorcinol-formaldehyde sol was coated on porous tubular resin support. The membrane was obtained by carbonisation of coated support. A well-combined top layer with the thickness of 35 μm was supported by macroporous support. Measurements of molecular weight cut-off using polyethylene glycol showed the average pore size of 8.3 nm. High salt rejection can be achieved because the water molecules need not overcome high energy barriers in confined space, while huge inherent dehydration energy was required for hydrated ions to enter the nanochannels. Additionally, carbon membrane with additional electric field can be used as an integrated membrane electrode combining the effects of confinement and electric potential gradient. Such membrane electrode can repel co-ions and attract counter-ions using pressure as the driving force for mass transport. When the carbon membrane was set as cathode, the rejection of SO₄²⁻ was 94.89%, while the removal of Na⁺ was less than 20%. We set carbon membrane as anode chamber to treat the effluent water from the cathode chamber. The rejection of SO₄²⁻ and Na⁺ reached to 100% and 88.86%, respectively. ECMD will be a promising energy efficient method for salt rejection.Keywords: nanoporous carbon membrane, confined effect, electric field, desalination, membrane reactor
Procedia PDF Downloads 1203209 Study Secondary Particle Production in Carbon Ion Beam Radiotherapy
Authors: Shaikah Alsubayae, Gianluigi Casse, Carlos Chavez, Jon Taylor, Alan Taylor, Mohammad Alsulimane
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Ensuring accurate radiotherapy with carbon therapy requires precise monitoring of radiation dose distribution within the patient's body. This monitoring is essential for targeted tumor treatment, minimizing harm to healthy tissues, and improving treatment effectiveness while lowering side effects. In our investigation, we employed a methodological approach to monitor secondary proton doses in carbon therapy using Monte Carlo simulations. Initially, Geant4 simulations were utilized to extract the initial positions of secondary particles formed during interactions between carbon ions and water. These particles included protons, gamma rays, alpha particles, neutrons, and tritons. Subsequently, we studied the relationship between the carbon ion beam and these secondary particles. Interaction Vertex Imaging (IVI) is valuable for monitoring dose distribution in carbon therapy. It provides details about the positions and amounts of secondary particles, particularly protons. The IVI method depends on charged particles produced during ion fragmentation to gather information about the range by reconstructing particle trajectories back to their point of origin, referred to as the vertex. In our simulations regarding carbon ion therapy, we observed a strong correlation between some secondary particles and the range of carbon ions. However, challenges arose due to the target's unique elongated geometry, which hindered the straightforward transmission of forward-generated protons. Consequently, the limited protons that emerged mostly originated from points close to the target entrance. The trajectories of fragments (protons) were approximated as straight lines, and a beam back-projection algorithm, using recorded interaction positions in Si detectors, was developed to reconstruct vertices. The analysis revealed a correlation between the reconstructed and actual positions.Keywords: radiotherapy, carbon therapy, monitoring of radiation dose, interaction vertex imaging
Procedia PDF Downloads 723208 Fabrication of Carbon Nanoparticles and Graphene Using Pulsed Laser Ablation
Authors: Davoud Dorranian, Hajar Sadeghi, Elmira Solati
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Carbon nanostructures in various forms were synthesized using pulsed laser ablation of a graphite target in different liquid environment. The beam of a Q-switched Nd:YAG laser of 1064-nm wavelength at 7-ns pulse width is employed to irradiate the solid target in water, acetone, alcohol, and cetyltrimethylammonium bromide (CTAB). Then the effect of the liquid environment on the characteristic of carbon nanostructures produced by laser ablation was investigated. The optical properties of the carbon nanostructures were examined at room temperature by UV–Vis-NIR spectrophotometer. The crystalline structure of the carbon nanostructures was analyzed by X-ray diffraction (XRD). The morphology of samples was investigated by field emission scanning electron microscope (FE-SEM). Transmission electron microscope (TEM) was employed to investigate the form of carbon nanostructures. Raman spectroscopy was used to determine the quality of carbon nanostructures. Results show that different carbon nanostructures such as nanoparticles and few-layer graphene were formed in various liquid environments. The UV-Vis-NIR absorption spectra of samples reveal that the intensity of absorption peak of nanoparticles in alcohol is higher than the other liquid environments due to the larger number of nanoparticles in this environment. The red shift of the absorption peak of the sample in acetone confirms that produced carbon nanoparticles in this liquid are averagely larger than the other medium. The difference in the intensity and shape of the absorption peak indicated the effect of the liquid environment in producing the nanoparticles. The XRD pattern of the sample in water indicates an amorphous structure due to existence the graphene sheets. X-ray diffraction pattern shows that the degree of crystallinity of sample produced in CTAB is higher than the other liquid environments. Transmission electron microscopy images reveal that the generated carbon materials in water are graphene sheet and in the other liquid environments are graphene sheet and spherical nanostructures. According to the TEM images, we have the larger amount of carbon nanoparticles in the alcohol environment. FE-SEM micrographs indicate that in this liquids sheet like structures are formed however in acetone, produced sheets are adhered and these layers overlap with each other. According to the FE-SEM micrographs, the surface morphology of the sample in CTAB was coarser than that without surfactant. From Raman spectra, it can be concluded the distinct shape, width, and position of the graphene peaks and corresponding graphite source.Keywords: carbon nanostructures, graphene, pulsed laser ablation, graphite
Procedia PDF Downloads 3083207 Thermophilic Anaerobic Granular Membrane Distillation Bioreactor for Wastewater Reuse
Authors: Duong Cong Chinh, Shiao-Shing Chen, Le Quang Huy
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Membrane distillation (MD) is actually claimed to be a cost-effective separation process when waste heat, alternative energy sources, or wastewater are used. To the best of our knowledge, this is the first study that a thermophilic anaerobic granular bioreactor is integrated with membrane distillation (ThAnMDB) was investigated. In this study, the laboratory scale anaerobic bioreactor (1.2 litter) was set-up. The bioreactor was maintained at temperature 55 ± 2°C, hydraulic retention time = 0.5 days, organic loading rates of 7 and 10 kg chemical oxygen demand (COD) m³/day. Side-stream direct contact membrane distillation with the polytetrafluoroethylene membrane area was 150 cm². The temperature of the distillate was kept at 25°C. Results show that distillate flux was 19.6 LMH (Liters per square meter per hour) on the first day and gradually decreased to 6.9 LMH after 10 days, and the membrane was not wet. Notably, by directly using the heat from the thermophilic anaerobic for MD separation process, all distilled water from wastewater was reuse as fresh water (electrical conductivity < 120 µs/cm). The ThAnMDB system showed its high pollutant removal performance: chemical oxygen demand (COD) from 99.6 to 99.9%, NH₄⁺ from 60 to 95%, and PO₄³⁻ complete removal. In addition, methane yield was from 0.28 to 0.34 lit CH₄/gram COD removal (80 – 97% of the theoretical) demonstrated that the ThAnMDB system was quite stable. The achievement of the ThAnMDB is not only in removing pollutants and reusing wastewater but also in absolutely unnecessarily adding alkaline to the anaerobic bioreactor system.Keywords: high rate anaerobic digestion, membrane distillation, thermophilic anaerobic, wastewater reuse
Procedia PDF Downloads 1243206 Role of Activated Partial Thromboplastin Time (APTT) to Assess the Need of Platelet Transfusion in Dengue
Authors: Kalyan Koganti
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Background: In India, platelet transfusions are given to large no. of patients suffering from dengue due to the fear of bleeding especially when the platelet counts are low. Though many patients do not bleed when the platelet count falls to less than 20,000, certain patients bleed even if the platelet counts are more than 20,000 without any comorbid condition (like gastrointestinal ulcer) in the past. This fear has led to huge amounts of unnecessary platelet transfusions which cause significant economic burden to low and middle-income countries like India and also sometimes these transfusions end with transfusion-related adverse reactions. Objective: To identify the role of Activated Partial Thromboplastin Time (APTT) in comparison with thrombocytoenia as an indicator to assess the real need of platelet transfusions. Method: A prospective study was conducted at a hospital in South India which included 176 admitted cases of dengue confirmed by immunochromatography. APTT was performed in all these patients along with platelet count. Cut off values of > 60 seconds for APTT and < 20,000 for platelet count were considered to assess the bleeding manifestations. Results: Among the total 176 patients, 56 patients had bleeding manifestations like malena, hematuria, bleeding gums etc. APTT > 60 seconds had a sensitivity and specificity of 93% and 90% respectively in identifying bleeding manifestations where as platelet count of < 20,000 had a sensitivity and specificity of 64% and 73% respectively. Conclusion: Elevated APTT levels can be considered as an indicator to assess the need of platelet transfusion in dengue. As there is a significant variation among patients who bleed with respect to platelet count, APTT can be considered to avoid unnecessary transfusions.Keywords: activated partial thromboplastin time, dengue, platelet transfusion, thrombocytopenia
Procedia PDF Downloads 2093205 Studying the Effect of Different Sizes of Carbon Fiber on Locally Developed Copper Based Composites
Authors: Tahir Ahmad, Abubaker Khan, Muhammad Kamran, Muhammad Umer Manzoor, Muhammad Taqi Zahid Butt
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Metal Matrix Composites (MMC) is a class of weight efficient structural materials that are becoming popular in engineering applications especially in electronic, aerospace, aircraft, packaging and various other industries. This study focuses on the development of carbon fiber reinforced copper matrix composite. Keeping in view the vast applications of metal matrix composites,this specific material is produced for its unique mechanical and thermal properties i.e. high thermal conductivity and low coefficient of thermal expansion at elevated temperatures. The carbon fibers were not pretreated but coated with copper by electroless plating in order to increase the wettability of carbon fiber with the copper matrix. Casting is chosen as the manufacturing route for the C-Cu composite. Four different compositions of the composite were developed by varying the amount of carbon fibers by 0.5, 1, 1.5 and 2 wt. % of the copper. The effect of varying carbon fiber content and sizes on the mechanical properties of the C-Cu composite is studied in this work. The tensile test was performed on the tensile specimens. The yield strength decreases with increasing fiber content while the ultimate tensile strength increases with increasing fiber content. Rockwell hardness test was also performed and the result followed the increasing trend for increasing carbon fibers and the hardness numbers are 30.2, 37.2, 39.9 and 42.5 for sample 1, 2, 3 and 4 respectively. The microstructures of the specimens were also examined under the optical microscope. Wear test and SEM also done for checking characteristic of C-Cu marix composite. Through casting may be a route for the production of the C-Cu matrix composite but still powder metallurgy is better to follow as the wettability of carbon fiber with matrix, in that case, would be better.Keywords: copper based composites, mechanical properties, wear properties, microstructure
Procedia PDF Downloads 3603204 Three Dimensional Vibration Analysis of Carbon Nanotubes Embedded in Elastic Medium
Authors: M. Shaban, A. Alibeigloo
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This paper studies free vibration behavior of single-walled carbon nanotubes (SWCNTs) embedded on elastic medium based on three-dimensional theory of elasticity. To accounting the size effect of carbon nanotubes, nonlocal theory is adopted to shell model. The nonlocal parameter is incorporated into all constitutive equations in three dimensions. The surrounding medium is modeled as two-parameter elastic foundation. By using Fourier series expansion in axial and circumferential direction, the set of coupled governing equations are reduced to the ordinary differential equations in thickness direction. Then, the state-space method as an efficient and accurate method is used to solve the resulting equations analytically. Comprehensive parametric studies are carried out to show the influences of the nonlocal parameter, radial and shear elastic stiffness, thickness-to-radius ratio and radius-to-length ratio.Keywords: carbon nanotubes, embedded, nonlocal, free vibration
Procedia PDF Downloads 4403203 Prediction of Mechanical Strength of Multiscale Hybrid Reinforced Cementitious Composite
Authors: Salam Alrekabi, A. B. Cundy, Mohammed Haloob Al-Majidi
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Novel multiscale hybrid reinforced cementitious composites based on carbon nanotubes (MHRCC-CNT), and carbon nanofibers (MHRCC-CNF) are new types of cement-based material fabricated with micro steel fibers and nanofilaments, featuring superior strain hardening, ductility, and energy absorption. This study focused on established models to predict the compressive strength, and direct and splitting tensile strengths of the produced cementitious composites. The analysis was carried out based on the experimental data presented by the previous author’s study, regression analysis, and the established models that available in the literature. The obtained models showed small differences in the predictions and target values with experimental verification indicated that the estimation of the mechanical properties could be achieved with good accuracy.Keywords: multiscale hybrid reinforced cementitious composites, carbon nanotubes, carbon nanofibers, mechanical strength prediction
Procedia PDF Downloads 1573202 SEM and FTIR Study of Adsorption Characteristics Using Xanthate (KIBX) Synthesized Collectors on Sphalerite
Authors: Zohir Nedjar, Djamel Barkat
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Thiols such as alkyl xanthates are commonly used as collectors in the froth flotation of sulfide minerals. Under the concen-tration, pH and Eh conditions relevant to flotation, the thermodynamically favoured reaction between a thiol and a sulfide mineral surface is charge transfechemisorption in which the collector becomes bonded to metal atoms in the outermost layer of the sulfide lattice. The adsorption of potassium isobutyl xanthate (KIBX 3.10-3M) on sphalerite has been also studied using electrochemical potential, FTIR technique and SEM. Non activated minerals and minerals activated with copper sulfate (10-4 M) and copper nitrate (10-4 M) have been investigated at pH = 7.5. Surface species have been identified by FTIR and correlated with SEM. After copper sulfate activation, copper xanthate exists on all of the minerals studied. Neutral pH is most favorable for potassium isobutyl xanthate adsorption on sphalerite.Keywords: flotation, adsorption, xanthate KIBX, sphalerite
Procedia PDF Downloads 3003201 Urea Amperometric Biosensor Based on Entrapment Immobilization of Urease onto a Nanostructured Polypyrrol and Multi-Walled Carbon Nanotube
Authors: Hamide Amani, Afshin FarahBakhsh, Iman Farahbakhsh
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In this paper, an amprometric biosensor based on surface modified polypyrrole (PPy) has been developed for the quantitative estimation of urea in aqueous solutions. The incorporation of urease (Urs) into a bipolymeric substrate consisting of PPy was performed by entrapment to the polymeric matrix, PPy acts as amperometric transducer in these biosensors. To increase the membrane conductivity, multi-walled carbon nanotubes (MWCNT) were added to the PPy solution. The entrapped MWCNT in PPy film and the bipolymer layers were prepared for construction of Pt/PPy/MWCNT/Urs. Two different configurations of working electrodes were evaluated to investigate the potential use of the modified membranes in biosensors. The evaluation of two different configurations of working electrodes suggested that the second configuration, which was composed of an electrode-mediator-(pyrrole and multi-walled carbon nanotube) structure and enzyme, is the best candidate for biosensor applications.Keywords: urea biosensor, polypyrrole, multi-walled carbon nanotube, urease
Procedia PDF Downloads 3163200 Progressive Loading Effect of Co Over SiO2/Al2O3 Catalyst for Cox Free Hydrogen and Carbon Nanotubes Production via Catalytic Decomposition of Methane
Authors: Sushil Kumar Saraswat, K. K. Pant
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Co metal supported on SiO2 and Al2O3 catalysts with a metal loading varied from 30 of 70 wt.% were evaluated for decomposition of methane to CO/CO2 free hydrogen and carbon nano materials. The catalytic runs were carried out from 550-800 oC under atmospheric pressure using fixed bed vertical flow reactor. The fresh and spent catalysts were characterized by BET surface area analyzer, TPR, XRD, SEM, TEM, and TG analysis. The data showed that 50% Co/Al2O3 catalyst exhibited remarkable higher activity and stability up to 10 h time-on-stream at 750 oC with respect to H2 production compared to rest of the catalysts. However, the catalytic activity and durability was greatly declined at a higher temperature. The main reason for the catalytic inhibition of Co containing SiO2 catalysts is the higher reduction temperature of Co2SiO4. TEM images illustrate that the carbon materials with various morphologies, carbon nanofibers (CNFs), helical-shaped CNFs, and branched CNFs depending on the catalyst composition and reaction temperature, were obtained. The TG data showed that a higher yield of MWCNTs was achieved over 50% Co/Al2O3 catalyst compared to other catalysts.Keywords: carbon nanotubes, cobalt, hydrogen production, methane decomposition
Procedia PDF Downloads 3173199 Critical Buckling Load of Carbon Nanotube with Non-Local Timoshenko Beam Using the Differential Transform Method
Authors: Tayeb Bensattalah, Mohamed Zidour, Mohamed Ait Amar Meziane, Tahar Hassaine Daouadji, Abdelouahed Tounsi
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In this paper, the Differential Transform Method (DTM) is employed to predict and to analysis the non-local critical buckling loads of carbon nanotubes with various end conditions and the non-local Timoshenko beam described by single differential equation. The equation differential of buckling of the nanobeams is derived via a non-local theory and the solution for non-local critical buckling loads is finding by the DTM. The DTM is introduced briefly. It can easily be applied to linear or nonlinear problems and it reduces the size of computational work. Influence of boundary conditions, the chirality of carbon nanotube and aspect ratio on non-local critical buckling loads are studied and discussed. Effects of nonlocal parameter, ratios L/d, the chirality of single-walled carbon nanotube, as well as the boundary conditions on buckling of CNT are investigated.Keywords: boundary conditions, buckling, non-local, differential transform method
Procedia PDF Downloads 2933198 Structural Characterization of the 3D Printed Silicon Carbon/Carbon Fibers Nanocomposites
Authors: Saja M. Nabat Al-Ajrash, Charles Browning, Rose Eckerle, Li Cao
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A process that utilizes a combination of additive manufacturing (AM), a preceramic polymer, and a chopped carbon fiber precursorto fabricate Silicon Carbon/ Carbon fibers (SiC/C) composites have been developed. The study has shown a promising, cost-effective, and efficient route to fabricate complex SiC/C composites using additive manufacturing. A key part of this effort was the mapping of the material’s microstructure through the thickness of the composite. Microstructural features in the pyrolyzed composites through the successive AM layers, such as defects, crystal size and their distribution, interatomic spacing, chemical bonds, were investigated using high-resolution scanning and transmission electron microscopy. As a result, the microstructure developed in SiC/C composites after printing, cure, and pyrolysis has been successfully mapped through the thickness of the derived composites. Dense and nearly defect-free parts after polymer to ceramic conversion were observed. The ceramic matrix composite displayed three coexisting phases, including silicon carbide, silicon oxycarbide, and turbostratic carbon. Lattice fringes imaging and X-Ray Diffraction analysis showed well-defined SiC and turbostratic carbon features. The cross-sectional mapping of the printed-then-pyrolyzed structures has confirmed consistent structural and chemical features within the internal layers of the AM parts. Noteworthy, however, is that a crust-like area with high crystallinity has been observed in the first and last external layers. Not only do these crust-like regions have structural characteristics distinct from the internal layers, but they also have elemental distributions different than the internal layers.Keywords: SiC, preceramic polymer, additive manufacturing, ceramic
Procedia PDF Downloads 733197 Carbon Footprint Assessment and Application in Urban Planning and Geography
Authors: Hyunjoo Park, Taehyun Kim, Taehyun Kim
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Human life, activity, and culture depend on the wider environment. Cities offer economic opportunities for goods and services, but cannot exist in environments without food, energy, and water supply. Technological innovation in energy supply and transport speeds up the expansion of urban areas and the physical separation from agricultural land. As a result, division of urban agricultural areas causes more energy demand for food and goods transport between the regions. As the energy resources are leaking all over the world, the impact on the environment crossing the boundaries of cities is also growing. While advances in energy and other technologies can reduce the environmental impact of consumption, there is still a gap between energy supply and demand by current technology, even in technically advanced countries. Therefore, reducing energy demand is more realistic than relying solely on the development of technology for sustainable development. The purpose of this study is to introduce the application of carbon footprint assessment in fields of urban planning and geography. In urban studies, carbon footprint has been assessed at different geographical scales, such as nation, city, region, household, and individual. Carbon footprint assessment for a nation and a city is available by using national or city level statistics of energy consumption categories. By means of carbon footprint calculation, it is possible to compare the ecological capacity and deficit among nations and cities. Carbon footprint also offers great insight on the geographical distribution of carbon intensity at a regional level in the agricultural field. The study shows the background of carbon footprint applications in urban planning and geography by case studies such as figuring out sustainable land-use measures in urban planning and geography. For micro level, footprint quiz or survey can be adapted to measure household and individual carbon footprint. For example, first case study collected carbon footprint data from the survey measuring home energy use and travel behavior of 2,064 households in eight cities in Gyeonggi-do, Korea. Second case study analyzed the effects of the net and gross population densities on carbon footprint of residents at an intra-urban scale in the capital city of Seoul, Korea. In this study, the individual carbon footprint of residents was calculated by converting the carbon intensities of home and travel fossil fuel use of respondents to the unit of metric ton of carbon dioxide (tCO₂) by multiplying the conversion factors equivalent to the carbon intensities of each energy source, such as electricity, natural gas, and gasoline. Carbon footprint is an important concept not only for reducing climate change but also for sustainable development. As seen in case studies carbon footprint may be measured and applied in various spatial units, including but not limited to countries and regions. These examples may provide new perspectives on carbon footprint application in planning and geography. In addition, additional concerns for consumption of food, goods, and services can be included in carbon footprint calculation in the area of urban planning and geography.Keywords: carbon footprint, case study, geography, urban planning
Procedia PDF Downloads 2853196 ORR Electrocatalyst for Batteries and Fuel Cells Development with SiO2/Carbon Black Based Composite Nanomaterials
Authors: Maryam Kiani
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This study focuses on the development of composite nanomaterials based on SiO2 and carbon black for oxygen reduction reaction (ORR) electrocatalysts in batteries and fuel cells. The aim was to explore the potential of these composite materials as efficient catalysts for ORR, which is a critical process in energy conversion devices. The SiO2/carbon black composite nanomaterials were synthesized using a facile and scalable method. The morphology, structure, and electrochemical properties of the materials were characterized using various techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), and electrochemical measurements. The results demonstrated that the incorporation of SiO2 into the carbon black matrix enhanced the ORR performance of the composite material. The composite nanomaterials exhibited improved electrocatalytic activity, enhanced stability, and increased durability compared to pure carbon black. The presence of SiO2 facilitated the formation of active sites, improved electron transfer, and increased the surface area available for ORR. This study contributes to the advancement of battery and fuel cell technology by offering a promising approach for the development of high-performance ORR electrocatalysts. The SiO2/carbon black composite nanomaterials show great potential for improving the efficiency and durability of energy conversion devices, leading to more sustainable and efficient energy solutions.Keywords: oxygen reduction reaction, batteries, fuel cells, electrrocatalyst
Procedia PDF Downloads 1023195 Camel Thorn Has Hepatoprotective Activity Against Carbon Tetrachloride or Acetaminophen-Induced Hepatotoxicity but Enhances the Cardiac Toxicity of Adriamycin in Rodents
Authors: Awad G. Abdellatif, Huda M. Gargoum, Abdelkader A. Debani, Mudafara Bengleil, Salmin Alshalmani, N. El Zuki, Omran El Fitouri
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In this study, the administration of 660 mg/kg of the ethanolic extract of the Alhgigraecorum (camel thorn) to mice, showed a significant decrease in the level of transaminases in animals treated with a combination of CTE plus carbon tetrachloride (CCl4) or acetaminophen as compared to animals receiving CCl4 or acetaminophen alone. The histopathological investigation also confirmed that camel thorn extract protects the liver against damage-induced either by carbon tetrachloride or acetaminophen. On the other hand, the cardiac toxicity produced by adriamycin was significantly increased in the presence of the ethanolic extract of camel thorn. Our study suggested that camel thorn can protect the liver against the injury produced by carbon tetrachloride or acetaminophen, with an unexpected increase in the cardiac toxicity–induced by adriamycin in rodents.Keywords: ethanolic, alhgigraecorum, tetrachloride, acetaminophen
Procedia PDF Downloads 4963194 Divalent Iron Oxidative Process for Degradation of Carbon and Nitrogen Based Pollutants from Dye Intermediate Industrial Wastewater
Authors: Nibedita Pani, Vishnu Tejani, T. S. Anantha Singh
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Water pollution resulting from discharge of partial/not treated textile wastewater containing high carbon and nitrogen pollutants pose a huge threat to the environment, ecosystem, and human health. It is essential to remove carbon- and nitrogen-based organic pollutants more effectively from industrial wastewater before discharging. The present study focuses on removal of carbon-based pollutant in particular COD (chemical oxygen demand) and nitrogen-based pollutants, in particular, ammoniacal nitrogen by Fenton oxidation process using Fe²⁺ and H₂O₂ as reagents. The study was carried out with high strength wastewater containing initial COD 5632 mg/L and NH⁴⁺-N 1372 mg/L. The major operating condition like pH was varied between 1.0 to 4.0. The maximum degradation was obtained at pH 3.0 taking the molar ratio of Fe²⁺/H₂O₂ as 1:1. At this pH, the removal efficiencies of COD and ammoniacal nitrogen were found to be 77.27% and 74.9%, respectively. The Fenton process can be the best alternative for the simultaneous removal of COD and NH4+-N from industrial wastewater.Keywords: ammoniacal nitrogen, COD, Fenton oxidation, industrial wastewater
Procedia PDF Downloads 195