Search results for: carbon transportation

Authors: Aditi Jain

Abstract:

Aim: To compare the canal transportation, centering ability and remaining dentin thickness of OneShape and WaveOne system using CBCT. Objective: To identify rotary system which respects original canal anatomy. Materials and Methods: Forty extracted human single-rooted premolars were used in the present study. Pre-instrumentation scans of all teeth were taken, canal curvatures were calculated, and the samples were randomly divided into two groups with twenty samples in each group, where Group 1 included WaveOne system and Group 2 Protaper rotary system. Post-instrumentation scans were performed, and the two scans were compared to determine canal transportation, centering ability and remaining dentin thickness at 1, 3, and 5 mm from the root apex. Results: Using Student’s unpaired t test results were as follows; for canal transportation Group 1 showed statistical significant difference at 3mm, 6mm and non-significant difference was obtained at 9mm but for Group 2 non-statistical significant difference was obtained at 3mm, 6mm, and 9mm. For centering ability and remaining dentin thickness Group 1 showed non-statistical significant difference at 3mm and 9mm, while statistical significant difference at 6mm was obtained. When comparison of remaining dentin thickness was done at three levels using two groups WaveOne and ProTaper. There was non-statistical significant difference between two groups. Conclusion: WaveOne single reciprocation file respects original canal anatomy better than ProTaper. WaveOne depicted the best centering ability.

Keywords: ShapeOne, WaveOne, transportation, centering ability, dentin thickness, CBCT (Cone Beam Computed Tomography)

Procedia PDF Downloads 207

Authors: Ali Zain Ul Abadeen, Arshad Hussain

Abstract:

Roads are considered as the national capital, and huge developmental budget is spent on its construction, maintenance, and rehabilitation. Due to proliferating traffic volume, heavier loads and challenging environmental factors, the need for high-performance asphalt pavement is increased. In this research, the asphalt mixture was modified with carbon nanotubes ranging from 0.2% to 2% of binder to study the effect of CNT modification on rutting potential and fatigue life of asphalt mixtures. During this study, the conventional and modified asphalt mixture was subjected to a uni-axial dynamic creep test and dry Hamburg wheel tracking test to study rutting resistance. Fatigue behavior of asphalt mixture was studied using a four-point bending test apparatus. The plateau value of asphalt mixture was taken as a measure of fatigue performance according to the ratio of dissipated energy approach. Results of these experiments showed that CNT modified asphalt mixtures had reduced rut depth and increased rutting and fatigue resistance at higher percentages of carbon nanotubes.

Keywords: carbon nanotubes, fatigue, four point bending test, modified asphalt, rutting

Procedia PDF Downloads 147

Authors: Aquil Ahmed, Srikant Gupta, Irfan Ali

Abstract:

In this paper, we study a multi-objective capacitated transportation problem (MOCTP) with mixed constraints. This paper is comprised of the modelling and optimisation of an MOCTP in a fuzzy environment in which some goals are fractional and some are linear. In real life application of the fuzzy goal programming (FGP) problem with multiple objectives, it is difficult for the decision maker(s) to determine the goal value of each objective precisely as the goal values are imprecise or uncertain. Also, we developed the concept of linearization of fractional goal for solving the MOCTP. In this paper, imprecision of the parameter is handled by the concept of fuzzy set theory by considering these parameters as a trapezoidal fuzzy number. α-cut approach is used to get the crisp value of the parameters. Numerical examples are used to illustrate the method for solving MOCTP.

Keywords: capacitated transportation problem, multi objective linear programming, multi-objective fractional programming, fuzzy goal programming, fuzzy sets, trapezoidal fuzzy number

Procedia PDF Downloads 436

Authors: Hassan Zare, Mohammad Jahedi, Mohammad Reza Toroghinejad, Mahmoud Meratian, Marko Knezevic

Abstract:

In this study, the carbon nanotube (CNT) reinforced Al matrix nanocomposites were fabricated by ECAP. Equal Channel Angular Pressing (ECAP) process is one of the most important methods for powder densification due to the presence of shear strain. This method samples with variety passes (one, two, four and eight passes) in C route were prepared at room temperature. A few study about metal matrix nanocomposite reinforced carbon nanotube done, the reaction intersection of interface and carbon nanotube cause to reduce the efficiency of nanocomposite. In this paper, we checked mechanical and physical properties of aluminum-CNT composite that manufactured by ECAP when the composite is deformed. The non-agglomerated CNTs were distributed homogeneously with 2% consolidation in the Aluminum matrix. The ECAP process was performed on the both monolithic and composite with distributed CNT samples for 8 passes.

Keywords: powder metallurgy, ball mill attrition, ultrasonic, consolidation

Procedia PDF Downloads 496

Authors: Blaž Likozar, Andraž Pavlišič, Matic Pavlin, Taja Žibert, Aleksandra Zamljen, Sašo Gyergyek, Matej Huš

Abstract:

Ammonia is gaining recognition as a carbon-free fuel for energy-intensive applications, particularly transportation, industry, and power generation. Due to its physical properties, high energy density of 3 kWh kg-1, and high gravimetric hydrogen capacity of 17.6 wt%, ammonia is an efficient energy vector for green hydrogen, capable of mitigating hydrogen’s storage, distribution, and infrastructure deployment limitations. Chemicalstorage in the form of ammonia provides an efficient and affordable solution for energy storage, which is currently a critical step in overcoming the intermittency of abundant renewable energy sources with minimal or no environmental impact. Experiments were carried out to validate the modelling in a packed bed reactor, which proved to be agreeing.

Keywords: hydrogen, ammonia, catalysis, modelling, kinetics

Procedia PDF Downloads 70

Authors: Taekyoon Park, Seokgoo Lee, Sungho Kim, Ung Lee, Jong Min Lee, Chonghun Han

Abstract:

CO2 capture and storage/sequestration (CCS) is a key technology for addressing the global warming issue. This paper proposes an integrated model for the whole chain of CCS, from a power plant to a reservoir. The integrated model is further utilized to determine optimal operating conditions and study responses to various changes in input variables.

Keywords: CCS, caron dioxide, carbon capture and storage, simulation, optimization

Procedia PDF Downloads 352

Authors: S. F. Halim, H. F. Naguib, S. N. Lawandy, R. S. Hegazy, M. N. Baheg

Abstract:

The main drawbacks of the traditional carbon fabric reinforced epoxy resin (CFRP) are low strain failure, delamination between composites layers, and low impact resistance due to the brittleness of epoxy resin. The aim of this study is to enhance the fracture properties of the CFRP composites laminates via the variation of composite's designs. A series of composites were fabricated in which bidirectional (00/900) carbon fabric (CF) layers were laid inside the resin matrix with orientation codes as F1 [(00, 900)/ (00, 900)], F2 [(900, 00)/ (00, 900)] and F3 [(00,900)/ (900, 00). The mechanical and dynamic properties of the composites were estimated. In addition, the morphology of samples surface was examined by scanning electron microscope (SEM) after impact fracture. The results revealed that the CFRP properties could be tailored fitting specific applications by controlling the fabric orientation inside the CFRP composite design. F2 orientation [(900, 00)/ (00.900)] showed the highest tensile and flexural strength values. On the other hand, the impact strength values of composites were in the order F1 > F2 > F3. The storage modulus, loss modulus, and glass transition temperature Tg values obtained from the dynamic mechanical analysis (DMA) examination was in the order F1 > F2 > F3. The variation in the properties of the composite was clearly explained by the SEM micrographs as the failure of F3 orientation properties was referred to as the complete breakage of the CF layers upon fracture.

Keywords: carbon fiber, CFRP, composites, epoxy resins, flexural strength

Procedia PDF Downloads 129

Authors: Yu Chen, Xiaoguang Yang, Lin Lin

Abstract:

Traffic engineering construction is an important infrastructure for economic and social development. In the process of construction and operation, the ability to make a correct evaluation of the project's environmental impact appears to be crucial to the rational operation of existing transportation projects, the correct development of transportation engineering construction and the adoption of corresponding measures to scientifically carry out environmental protection work. Most of the existing research work on ecological and environmental impact assessment is limited to individual aspects of the environment and less to the overall evaluation of the environmental system; in terms of research conclusions, there are more qualitative analyses from the technical and policy levels, and there is a lack of quantitative research results and quantitative and operable evaluation models. In this paper, a comprehensive analysis of the ecological and environmental impacts of transportation construction projects is conducted, and factors such as the accessibility of data and the reliability of calculation results are comprehensively considered to extract indicators that can reflect the essence and characteristics. The qualitative evaluation indicators were screened using the expert review method, the qualitative indicators were measured using the fuzzy statistics method, the quantitative indicators were screened using the principal component analysis method, and the quantitative indicators were measured by both literature search and calculation. An environmental impact evaluation index system with the general objective layer, sub-objective layer and indicator layer was established, dividing the environmental impact of the transportation construction project into two periods: the construction period and the operation period. On the basis of the evaluation index system, the index weights are determined using the hierarchical analysis method, and the individual indicators to be evaluated are dimensionless, eliminating the influence of the original background and meaning of the indicators. Finally, the thesis uses the above research results, combined with the actual engineering practice, to verify the correctness and operability of the evaluation method.

Keywords: transportation construction projects, ecological and environmental impact, analysis and evaluation, indicator evaluation system

Procedia PDF Downloads 108

Authors: Pongchan Na-Lampang

Abstract:

The objective of this study was to compare the results of transport of slaughter pigs to slaughterhouse by 2 methods, i.e. individual confined and group confined on the truck on meat quality. The pigs were transported for 1 h on a distance of 70 km. The stocking densities were 0.35 m2/pig and 0.48 m2 for group and individual crate treatment, respectively. It was found that meat quality of pigs transported by 2 different methods as measured in terms of pH level (at 45 min and 48 hr post mortem), color (brightness, redness and yellowness) and water holding capacity was not significantly different.

Keywords: market pig, transportation, meat quality, confinement

Procedia PDF Downloads 390

Authors: Sarita Sindhu, Vinay Kumar

Abstract:

The growing demand for efficient energy storage in applications such as portable electronics, electric vehicles, and renewable energy systems has emphasized the need for advanced energy storage materials. This study addresses the pressing need for efficient energy storage materials by exploring the synthesis and application of a composite of activated carbon (AC) and nickel sulfide (NiS) for supercapacitors. Activated carbon, possessing high surface area and excellent electrochemical stability, was combined with nickel sulfide, a transition metal sulfide with high theoretical capacitance, to enhance the electrochemical performance of the composite material. Characterization techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), were employed to analyze the morphology, crystalline structure, and bonding characteristics, confirming the successful formation of a uniformly distributed AC/NiS composite. Electrochemical evaluations revealed that the AC/NiS composite exhibited superior capacitance, excellent rate capability, and enhanced cycling stability compared to pure AC and NiS. The synergistic effect of the large surface area from activated carbon and redox-active sites of nickel sulfide provided an improved energy storage capacity, making this composite a promising electrode material for high-performance supercapacitors.

Keywords: activated carbon, energy storage, sulfide, surface area

Procedia PDF Downloads 16

Authors: Jollen Dai, Truman You, Xinyun Du, Katrina Liu

Abstract:

Transportation is one of the leading sources of greenhouse gas emissions (GHG). Thus, to meet the Paris Agreement 2015, all countries must adopt a different and more sustainable transportation system. From bikes to Maglev, the world is slowly shifting to sustainable transportation. To develop a utility public transit system, a sustainable web of buses must be implemented. As of now, only a handful of cities have adopted a detailed plan to implement a full fleet of e-buses by the 2030s, with Shenzhen in the lead. Every change requires a detailed plan and a focused analysis of the impacts of the change. In this report, the economic implications and financial implications have been taken into consideration to develop a well-rounded 10-year plan for New York City. We also apply the same financial model to the other cities, LA and Chicago. We picked NYC, Chicago, and LA to conduct the comparative NPB analysis since they are all big metropolitan cities and have complex transportation systems. All three cities have started an action plan to achieve a full fleet of e-bus in the decades. Plus, their energy carbon footprint and their energy price are very different, which are the key factors to the benefits of electric buses. Using TCO (Total Cost Ownership) financial analysis, we developed a model to calculate NPB (Net Present Benefit) /and compare EBS (electric buses) to DBS (diesel buses). We have considered all essential aspects in our model: initial investment, including the cost of a bus, charger, and installation, government fund (federal, state, local), labor cost, energy (electricity or diesel) cost, maintenance cost, insurance cost, health and environment benefit, and V2G (vehicle to grid) benefit. We see about $1,400,000 in benefits for a 12-year lifetime of an EBS compared to DBS provided the government fund to offset 50% of EBS purchase cost. With the government subsidy, an EBS starts to make positive cash flow in 5th year and can pay back its investment in 5 years. Please remember that in our model, we consider environmental and health benefits, and every year, $50,000 is counted as health benefits per bus. Besides health benefits, the significant benefits come from the energy cost savings and maintenance savings, which are about $600,000 and $200,000 in 12-year life cycle. Using linear regression, given certain budget limitations, we then designed an optimal three-phase process to replace all NYC electric buses in 10 years, i.e., by 2033. The linear regression process is to minimize the total cost over the years and have the lowest environmental cost. The overall benefits to replace all DBS with EBS for NYC is over $2.1 billion by the year of 2033. For LA, and Chicago, the benefits for electrification of the current bus fleet are $1.04 billion and $634 million by 2033. All NPB analyses and the algorithm to optimize the electrification phase process are implemented in Python code and can be shared.

Keywords: financial modeling, total cost ownership, net present benefits, electric bus, diesel bus, NYC, LA, Chicago

Procedia PDF Downloads 52

Authors: Nebiyou Masebo

Abstract:

The rapid conversion of an old aged agroforestry (AF) based agricultural system to monocropping farming system in southern Ethiopia is increasing. The consequence of this, combined with climate change, has been impaired biodiversity, soil microbial biomass carbon (MBC), and soil organic carbon (SOC). The AF system could curb such problems due it is an ecologically and economically sustainable strategies. This study was aimed to investigate different agroforestry practices (AFPs) on MBC and SOC in southern Ethiopia. Soil samples were collected from homegarden based agroforestry practice (HAFP), crop land based agroforestry practice (ClAFP), woodlot based agroforestry practice (WlAFP), and trees on soil and water conservation based agroforestry practice (TSWAFP) using two depth layer (0-30 & 30-60 cm) by systematic sampling. Moreover, woody species inventorywas also collected. The chloroform fumigation extraction method was employed to determine MBC from different AFP types. In this study, the value of MBC and SOC decreased significantly with soil depth (p< 0.05). Besides, AFP type, soil depth, woody species diversity, and key soil properties also strongly influenced MBC and SOC (p< 0.05). In this study, the MBC was the highest (786 mg kg⁻¹ soil) in HAFP, followed by WlAFP (592 mg kg⁻¹ soil), TSWAFP (421 mg kg⁻¹ soil), and ClAFP (357 mg kg⁻¹ soil). The highest mean value of SOC (43.5Mg C ha⁻¹) was recorded in HAFP, followed by WlAFP (35.1Mg C ha⁻¹), TSWAFP (22.3 Mg C ha⁻¹), while the lowest (21.8 Mg C ha⁻¹) was recorded in ClAFP. The HAFP had high woody species diversity, and the lowest was recorded in ClAFP. The finding indicated that SOC and MBC were significantly affected by land management practices, and HAFP has the potential to improve MBC and SOC through good management practices of AFP.

Keywords: agroforestry practices, microbial biomass carbon, soil carbon, rapid conversion

Procedia PDF Downloads 102

Authors: B. F. Dada, B. S. Ewulo, M. A. Awodun, S. O. Ajayi

Abstract:

Aggregate soil carbon distribution and stock in the soil in the form of a carbon pool is important for soil fertility and sequestration. The amount of carbon pool and other nutrients statues of the soil are to benefit plants, animal and the environment in the long run. This study was carried out at Akure North and South Local Government; the study area is one of the 18 Local Government Areas of Ondo State in the Southwest geo-political zone of Nigeria. The sites were divided into Map Grids and geo-referenced with Global Positioning System (GPS). Horizons were designated and morphological description carried out on the field. Pedons were characterized and classified according to USDA soil taxonomy. The local government area shares boundaries with; Ikere Local Government (LG) in the North, Ise Orun LG in the northwest, Ifedore LG in the northeast Akure South LG in the East, Ose LG in the South East, and Owo LG in the South. SOC-pool at Federal College of Agriculture topsoil horizon A2 is significantly higher than all horizons, 67.83 th⁻¹. The chemical properties of the pedons have shown that the soil is very strongly acidic to neutral reaction (4.68 – 6.73). The nutrients status of the soil topsoil A1 and A2 generally indicates that the soils have a low potential for retaining plant nutrients, and therefore call for adequate soil management.

Keywords: soil organic carbon (SOC), horizon, pedon, Akure

Procedia PDF Downloads 151

Authors: B. Hekner, J. Myalski, P. Wrzesniowski

Abstract:

This study presents aluminum matrix composites reinforced by glassy carbon (GC) and titanium (Ti). In the first step, the heterophase (GC+Ti), spatial form (similar to skeleton) of reinforcement was obtained via own method. The polyurethane foam (with spatial, open-cells structure) covered by suspension of Ti particles in phenolic resin was pyrolyzed. In the second step, the prepared heterogeneous foams were infiltrated by aluminium alloy. The manufactured composites are designated to industrial application, especially as a material used in tribological field. From this point of view, the glassy carbon was applied to stabilise a coefficient of friction on the required value 0.6 and reduce wear. Furthermore, the wear can be limited due to titanium phase application, which reveals high mechanical properties. Moreover, fabrication of thin titanium layer on the carbon skeleton leads to reduce contact between aluminium alloy and carbon and thus aluminium carbide phase creation. However, the main modification involves the manufacturing of reinforcement in the form of 3D, skeleton foam. This kind on reinforcement reveals a few important advantages compared to classical form of reinforcement-particles: possibility to control homogeneity of reinforcement phase in composite material; low-advanced technique of composite manufacturing- infiltration; possibility to application the reinforcement only in required places of material; strict control of phase composition; High quality of bonding between components of material. This research is founded by NCN in the UMO-2016/23/N/ST8/00994.

Keywords: metal matrix composites, MMC, glassy carbon, heterophase composites, tribological application

Procedia PDF Downloads 118

Authors: Manisha Bal, Amit Verma, B. C. Meikap

Abstract:

Carbon dioxide (CO₂) is the most abundant waste produced by human activities. It is estimated to be one of the major contributors of greenhouse effect and also considered as a major air pollutant formed by burning of fossil fuels. The main sources of emissions are flue gas from thermal power plants and process industries. It is also a contributor of acid rain. Its exposure through inhalation can lead to health risks. Therefore, control of CO₂ emission in the environment is very necessary. The main focus of this study is on the removal of carbon dioxide from off gases using a self-priming venturi scrubber in submerged conditions using sodium hydroxide as the scrubbing liquid. A self-priming submerged venturi scrubber is an efficient device to remove gaseous pollutants. In submerged condition, venturi scrubber remains submerged in the liquid tank and the liquid enters at the throat section of venturi scrubber due to the pressure difference which includes the hydrostatic pressure of the liquid and static pressure of the gas. The inlet polluted air stream enters through converging section which moves at very high velocity in the throat section and atomizes the liquid droplets. This leads to absorption of CO₂ from the off gases in scrubbing liquid which resulted in removal of CO₂ gas from the off gases. Detailed investigation on the scrubbing of carbon dioxide has been done in this literature. Experiments were conducted at different throat gas velocities, liquid levels in outer cylinder and CO₂ inlet concentrations to study the carbon dioxide removal efficiency. Experimental results give more than 95% removal efficiency of CO₂ in the self priming venturi scrubber which can meet the environmental emission limit of CO₂ to save the human life.

Keywords: carbon dioxide, scrubbing, pollution control, self-priming venturi scrubber

Procedia PDF Downloads 222

Authors: Asanka U. K. Godamunne

Abstract:

Road traffic accidents (RTA) are a leading cause of death globally as well as in Sri Lanka and results in a large proportion of disability especially among young people. Ninety-percent of world’s road traffic deaths occur in low- and middle-income countries. The gross disparities in injury outcomes relate to immediate post-crash and hospital management. Emergency management, methods of patient transportation following road traffic accidents and safety measures are important factors to reduce mortality and morbidity. Studies in this area are limited in Sri Lanka. The main objective of this research was to assess the emergency management and proper method of transportation of road traffic accident victims. This offers the best way to explore the ways to reduce the mortality and morbidity and raise the public awareness. This study was conducted as a descriptive cross-sectional study. All the consecutive road traffic accident victims admitted to surgical wards at District General Hospital, Matale, Sri Lanka, over a period of three months were included in the study. Data from 387 victims were analyzed. The majority were in the 20-30 year age group. Seventy six percent of the patients were males. Motorcycles and trishaws were most affected. First-aid was given to only 2% of patients and it was given by non-medical persons. A significant proportion of patients (75%) were transported to the hospital by trishaws and only 1% transported by ambulance. About 86% of the patients were seated while transport and 14% were flat. Limbs and head were the most affected areas of the body. As per this study, immediate post-crash management and patient transportation were not satisfactory. There is a need to strengthen certain road safety laws and make sure people follow them.

Keywords: emergency management, patient transportation, road traffic accident victims, Sri Lanka

Procedia PDF Downloads 249

Authors: Henrique Gomes dos Santos, Manoel Henrique Alves, Jane Zoppas Ferreira, Annelise Kopp Alves

Abstract:

This work aimed to seek an environmentally sustainable surface coating alternative by researching the influence of the addition of graphene oxide (GO) and carbon nanotubes (CNT) on the silanization of coatings to increase the wear resistance in galvanized steel, using the pin-on-disk test. The results obtained were compared between different concentrations of additives and the number of coating layers, in addition to comparing with samples without coating and only with silane layers. Bis-1,2-(triethoxysilyl)ethane (BTSE) silane was used in silanizing the coatings with CNT or GO and applied to the samples through dip-coating to form one, four, or eight layers. The wear test results found that three samples stood out in relation to the objective, showing an increase in wear resistance compared to the galvanized sample only. The rolling effect and the lubricity character presented by carbon nanotubes were positive for the increase in wear resistance obtained. The reduction in wear compared to the galvanized-only sample reached 82%. Raman spectroscopy was also carried out to detect the presence of silane, GO, and CNT, in addition to roughness tests and SEM to assess the homogeneity of the coating. The carbonaceous additives, graphene oxide, and carbon nanotubes in certain amounts of layers and specific concentrations fulfilled their objective against the wear imposed on the substrate.

Keywords: silane, coating, graphene oxide, carbon nanotubes, wear resistance

Procedia PDF Downloads 20

Authors: Mohamed Eldessouki, Ebraheem Shady, Yasser Gowayed

Abstract:

Carbon nanotubes (CNTs) are known for having high elastic properties with high surface area that promote them as good candidates for reinforcing polymeric matrices. In composite materials, CNTs lack chemical bonding with the surrounding matrix which decreases the possibility of better stress transfer between the components. In this work, a chemical treatment for activating the surface of the multi-wall carbon nanotubes (MWCNT) was applied and the effect of this functionalization on the elastic properties of the epoxy nanocomposites was studied. Functional amino-groups were added to the surface of the CNTs and it was evaluated to be about 34% of the total weight of the CNTs. Elastic modulus was found to increase by about 40% of the neat epoxy resin at CNTs’ weight fraction of 0.5%. The elastic modulus was found to decrease after reaching a certain concentration of CNTs which was found to be 1% wt. The scanning electron microscopic pictures showed the effect of the CNTs on the crack propagation through the sample by forming stress concentrated spots at the nanocomposite samples.

Keywords: carbon nanotubes functionalization, crack propagation, elastic modulus, epoxy nanocomposites

Procedia PDF Downloads 407

Authors: Gia Surguladze, Nino Topuria, Lily Petriashvili, Giorgi Surguladze

Abstract:

Modeling of building processes of a multimodal freight transportation support information system is discussed based on modern CASE technologies. Functional efficiencies of ports in the eastern part of the Black Sea are analyzed taking into account their ecological, seasonal, resource usage parameters. By resources, we mean capacities of berths, cranes, automotive transport, as well as work crews and neighbouring airports. For the purpose of designing database of computer support system for Managerial (Logistics) function, using Object-Role Modeling (ORM) tool (NORMA – Natural ORM Architecture) is proposed, after which Entity Relationship Model (ERM) is generated in automated process. The software is developed based on Process-Oriented and Service-Oriented architecture, in Visual Studio.NET environment.

Keywords: seaport resources, business-processes, multimodal transportation, CASE technology, object-role model, entity relationship model, SOA

Procedia PDF Downloads 431

Authors: Zhongnan Ye, Xiaoyi Liu, Shu-Chien Hsu

Abstract:

Rapid urbanization has led to a significant increase in construction and demolition waste (C&D waste), underscoring the need for sustainable waste management strategies in the construction industry. Aiming to enhance the sustainability of urban construction practices, this study develops an optimization model to effectively suggest the optimal recycling and reuse strategies for C&D waste, including concrete and steel. By employing Life Cycle Assessment (LCA), the model evaluates the environmental impacts of adopted construction materials throughout their lifecycle. The model optimizes the quantity of materials to recycle or reuse, the selection of specific recycling and reuse processes, and logistics decisions related to the transportation and storage of recycled materials with the objective of minimizing the overall environmental impact, quantified in terms of carbon emissions, energy consumption, and associated costs, while adhering to a range of constraints. These constraints include capacity limitations, quality standards for recycled materials, compliance with environmental regulations, budgetary limits, and temporal considerations such as project deadlines and material availability. The strategies are expected to be both cost-effective and environmentally beneficial, promoting a circular economy within the construction sector, aligning with global sustainability goals, and providing a scalable framework for managing construction waste in densely populated urban environments. The model is helpful in reducing the carbon footprint of construction projects, conserving valuable resources, and supporting the industry’s transition towards a more sustainable future.

Keywords: circular construction, construction and demolition waste, material recycling, optimization modeling

Procedia PDF Downloads 57

Authors: Zhongnan Ye, Xiaoyi Liu, Shu-Chien Hsu

Abstract:

Rapid urbanization has led to a significant increase in construction and demolition waste (C&D waste), underscoring the need for sustainable waste management strategies in the construction industry. Aiming to enhance the sustainability of urban construction practices, this study develops an optimization model to effectively suggest the optimal recycling and reuse strategies for C&D waste, including concrete and steel. By employing Life Cycle Assessment (LCA), the model evaluates the environmental impacts of adopted construction materials throughout their lifecycle. The model optimizes the quantity of materials to recycle or reuse, the selection of specific recycling and reuse processes, and logistics decisions related to the transportation and storage of recycled materials with the objective of minimizing the overall environmental impact, quantified in terms of carbon emissions, energy consumption, and associated costs, while adhering to a range of constraints. These constraints include capacity limitations, quality standards for recycled materials, compliance with environmental regulations, budgetary limits, and temporal considerations such as project deadlines and material availability. The strategies are expected to be both cost-effective and environmentally beneficial, promoting a circular economy within the construction sector, aligning with global sustainability goals, and providing a scalable framework for managing construction waste in densely populated urban environments. The model is helpful in reducing the carbon footprint of construction projects, conserving valuable resources, and supporting the industry’s transition towards a more sustainable future.

Keywords: circular construction, construction and demolition waste, life cycle assessment, material recycling

Procedia PDF Downloads 82

Authors: Mohamed K. El-Fawkhry, Ahmed Shash, Ahmed Ismail Zaki Farahat, Sherif Ali Abd El Rahman, Taha Mattar

Abstract:

High-carbon, silicon-rich steels are commonly suggested to obtain very fine bainitic microstructure at low temperature ranged from 200 to 300°C. Thereby, the resulted microstructure consists of slender of bainitic-ferritic plates interwoven with retained austenite. The advanced strength and ductility package of this steel is much dependent on the fineness of bainitic ferrite, as well as the retained austenite phase. In this article, Aluminum to Silicon ratio, and the isothermal transformation temperature have been adopted to obtain ultra high strength high carbon steel. Optical and SEM investigation of the produced steels have been performed. XRD has been used to track the retained austenite development as a result of the change in the chemical composition of developed steels and heat treatment process. Mechanical properties in terms of hardness and microhardness of obtained phases and structure were investigated. It was observed that the increment of aluminum to silicon ratio has a great effect in promoting the bainitic transformation, in tandem with improving the stability and the fineness of retained austenite. Such advanced structure leads to enhancement in the whole mechanical properties of the high carbon steel.

Keywords: high-carbon steel, silicon-rich steels, fine bainitic microstructure, retained austenite, isothermal transformation

Procedia PDF Downloads 351

Authors: Sardar Khana, Zar Ali Khana

Abstract:

Rapid industrial development and urbanization contribute a lot to wastewater discharge. The wastewater enters into natural aquatic ecosystems from industrial activities and considers as one of the main sources of water pollution. Discharge of effluents loaded with heavy metals into the surrounding environment has become a key issue regarding human health risk, environment, and food chain contamination. Nickel causes fatigue, cancer, headache, heart problems, skin diseases (Nickel Itch), and respiratory disorders. Nickel compounds such as Nickel Sulfide and Nickel oxides in industrial environment, if inhaled, have an association with an increased risk of lung cancer. Therefore the removal of Nickel from effluents before discharge is necessary. Removal of Nickel by low-cost biosorbents is an efficient method. This study was aimed to investigate the efficiency of activated carbon and Pinusroxburgiisaw dust for the removal of Nickel from industrial effluents using commercial Activated Carbon, and raw P.roxburgii saw dust. Batch and column adsorption experiments were conducted for the removal of Nickel. The study conducted indicates that removal of Nickel greatly dependent on pH, contact time, Nickel concentration, and adsorbent dose. Maximum removal occurred at pH 9, contact time of 600 min, and adsorbent dose of 1 g/100 mL. The highest removal was 99.62% and 92.39% (pH based), 99.76% and 99.9% (dose based), 99.80% and 100% (agitation time), 92% and 72.40% (Ni Conc. based) for P.roxburgii saw dust and activated Carbon, respectively. Similarly, the Ni removal in column adsorption was 99.77% and 99.99% (bed height based), 99.80% and 99.99% (Concentration based), 99.98%, and 99.81% (flow rate based) during column studies for Nickel using P.Roxburgiisaw dust and activated carbon, respectively. Results were compared with Freundlich isotherm model, which showed “r2” values of 0.9424 (Activated carbon) and 0.979 (P.RoxburgiiSaw Dust). While Langmuir isotherm model values were 0.9285 (Activated carbon) and 0.9999 (P.RoxburgiiSaw Dust), the experimental results were fitted to both the models. But the results were in close agreement with Langmuir isotherm model.

Keywords: nickel removal, batch, and column, activated carbon, saw dust, plant uptake

Procedia PDF Downloads 133

Authors: Ramin Mirzada, Takuya Maruyama

Abstract:

Kabul is the heart of political, commercial, cultural, educational and social life in Afghanistan and the fifth fastest growing city in the world. Minimum income inclined most of Kabul residents to use public transport, especially buses, although there is no proper bus system, beside that there is no proper fare exist in Kabul city Due to wars. From 1992 to 2001 during civil wars, Kabul suffered damage and destruction of its transportation facilities including pavements, sidewalks, traffic circles, drainage systems, traffic signs and signals, trolleybuses and almost all of the public transport system (e.g. Millie bus). This research is mainly focused on Kabul city’s transportation system. In this research, the data used have been gathered by Japan International Cooperation Agency (JICA) in 2008 and this data will be used to find demand and fare structure, additionally a survey was done in 2016 to find satisfaction level of Kabul residents for fare structure. Aim of this research is to observe the demand for Large Buses, compare to the actual supply from the government, analyze the current fare structure and compare it with the proposed fare (distance based fare) structure which has already been analyzed. Outcome of this research shows that the demand of Kabul city residents for the public transport (Large Buses) exceeds from the current supply, so that current public transportation (Large Buses) is not sufficient to serve public transport in Kabul city, worth to be mentioned, that in order to overcome this problem, there is no need to build new roads or exclusive way for buses. This research proposes government to change the fare from fixed fare to distance based fare, invest on public transportation and increase the number of large buses so that the current demand for public transport is met.

Keywords: transportation, planning, public transport, large buses, Kabul, Afghanistan

Procedia PDF Downloads 315

Authors: Mukul Kumar Srivastava, Sumit Basu

Abstract:

Carbon fiber reinforced polymer (CFRP) composites find wide use in the space and aerospace industries primarily due to their favourable strength-to-weight ratios. However, in spite of the impressive mechanical properties, their ability to shield sophisticated electronics from electromagnetic interference (EMI) is rather limited. As a result, metallic wire meshes or metal foils are often embedded in CFRP composites to provide adequate EMI shielding. This comes at additional manufacturing cost, increased weight and, particularly in cases of aluminium, increased risk of galvanic corrosion in the presence of moisture. In this work, we will explore ways of enhancing EMI shielding of CFRP laminates in the 8-12 GHz range (the so-called X-band), without compromising their mechanical and fracture properties, through minimal modifications to their current well-established fabrication protocol. The computational-experimental study of EMI shielding in CFRP laminates will focus on the effects of incorporating multiwalled carbon nanotubes (MWCNT) and conducting nanoparticles in different ways in the resin and/or carbon fibers. We will also explore the possibility of utilising the excellent absorbing properties of MWCNT reinforced polymer foams to enhance the overall EMI shielding capabilities.

Keywords: EMI shielding, X-band, CFRP, MWCNT

Procedia PDF Downloads 83

Authors: Ibrahim Halil Korkmaz, Eren Özceylan, Cihan Çetinkaya

Abstract:

Logistics function has great potential for increasing sustainable competitive advantage, profitability, productivity, customer satisfaction and decreasing costs in all sectors. The performance of logistics sector, which has such great influence on the overall performance of the economy, attracts more attention of both researchers and sector representatives day by day. The purpose of this study is to determine the effects of research and development expenditures which spent by enterprises operating in the transportation and storage sectors on Turkey’s logistic performance index (LPI). To do so, research and development investment expenditure among the years 2009-2015 of Turkish transportation and storage firms data from the Turkish Statistical Institute and Turkeys country points in the World Bank logistics performance index in the same years data were examined. As the result of the parametric evaluation, it is seen that the research and development expenditures made have a positive effect on the logistic performance of Turkey.

Keywords: logistics performance index, R&D investments, transportation, storage, Turkey

Procedia PDF Downloads 322

Authors: Nikolai A. Khlebnikov, Vladimir N. Krasilnikov, Evgenii V. Polyakov, Anastasia A. Maltceva

Abstract:

Carbon materials with advanced surfaces are widely used both in modern industry and in environmental protection. The physical-chemical nature of these materials is determined by the morphology of primary atomic and molecular carbon structures, which are the basis for synthesizing the following materials: zero-dimensional (fullerenes), one-dimensional (fiber, tubes), two-dimensional (graphene) carbon nanostructures, three-dimensional (multi-layer graphene, graphite, foams) with unique physical-chemical and functional properties. Experience shows that the microscopic morphological level is the basis for the creation of the next mesoscopic morphological level. The dependence of the morphology on the chemical way and process prehistory (crystallization, colloids formation, liquid crystal state and other) is the peculiarity of the last called level. These factors determine the consumer properties of carbon materials, such as specific surface area, porosity, chemical resistance in corrosive environments, catalytic and adsorption activities. Based on the developed ideology of thin precursor synthesis, the authors discuss one of the approaches of the porosity control of carbon-containing materials with a given aggregates morphology. The low-temperature thermolysis of precursors in a gas environment of a given composition is the basis of the above-mentioned idea. The processes of carbothermic precursor synthesis of two different compounds: tungsten carbide WC:nC and zinc oxide ZnO:nC containing an impurity phase in the form of free carbon were selected as subjects of the research. In the first case, the transition metal (tungsten) forming carbides was the object of the synthesis. In the second case, there was selected zinc that does not form carbides. The synthesis of both kinds of transition metals compounds was conducted by the method of precursor carbothermic synthesis from the organic solution. ZnO:nC composites were obtained by thermolysis of succinate Zn(OO(CH2)2OO), formate glycolate Zn(HCOO)(OCH2CH2O)1/2, glycerolate Zn(OCH2CHOCH2OH), and tartrate Zn(OOCCH(OH)CH(OH)COO). WC:nC composite was synthesized from ammonium paratungstate and glycerol. In all cases, carbon structures that are specific for diamond- like carbon forms appeared on the surface of WC and ZnO particles after the heat treatment. Tungsten carbide and zinc oxide were removed from the composites by selective chemical dissolution preserving the amorphous carbon phase. This work presents the results of investigating WC:nC and ZnO:nC composites and carbon nanopowders with tubular, tape, plate and onion morphologies of aggregates that are separated by chemical dissolution of WC and ZnO from the composites by the following methods: SEM, TEM, XPA, Raman spectroscopy, and BET. The connection between the carbon morphology under the conditions of synthesis and chemical nature of the precursor and the possibility of regulation of the morphology with the specific surface area up to 1700-2000 m2/g of carbon-structured materials are discussed.

Keywords: carbon morphology, composite materials, precursor synthesis, tungsten carbide, zinc oxide

Procedia PDF Downloads 336

Authors: Saeid Shahraki, Mohammad Mahdi Kaekha

Abstract:

1030 steel, a kind of carbon steel used in homogenization, cold-forming, quenching, and tempering conditions, is generally utilized in small parts resisting medium stress, such as connection foundations, hydraulic cylinders, tiny gears, pins, clamps, automotive normal forging parts, camshafts, levers, pundits, and nuts. In this study, AC3 software was used to measure the effect of carbon and manganese percentage, dimensions and geometry of pieces, the type of the cooling fluid, temperature, and time on hardness and the content of 1030 steel phases. Next, the results are compared with the analytical values obtained from the Lumped Capacity Method.

Keywords: 1030Steel, AC3software, heat treatment, lumped capacity method

Procedia PDF Downloads 284

Authors: Pallavi Bhogaram, Xiaolong Wu, Min He, Onyedikachi Okenwa

Abstract:

A transportation network is a realization of a spatial network, describing a structure which permits either vehicular movement or flow of some commodity. Examples include road networks, railways, air routes, pipelines, and many more. The transportation network plays a vital role in maintaining the vigor of the nation’s economy. Hence, ensuring the network stays resilient all the time, especially in the face of challenges such as heavy traffic loads and large scale natural disasters, is of utmost importance. In this paper, we used the Neo4j application to develop the graph. Neo4j is the world's leading open-source, NoSQL, a native graph database that implements an ACID-compliant transactional backend to applications. The Southern California network model is developed using the Neo4j application and obtained the most critical and optimal nodes and paths in the network using centrality algorithms. The edge betweenness centrality algorithm calculates the critical or optimal paths using Yen's k-shortest paths algorithm, and the node betweenness centrality algorithm calculates the amount of influence a node has over the network. The preliminary study results confirm that the Neo4j application can be a suitable tool to study the important nodes and the critical paths for the major congested metropolitan area.

Keywords: critical path, transportation network, connectivity reliability, network model, Neo4j application, edge betweenness centrality index

Procedia PDF Downloads 135

Authors: Kai-Wei Huang, Yi-Feng Lin

Abstract:

The purpose of this study is to have chemical resistance, high heat resistance and mechanical strength of ceramic hollow fiber membrane into a membrane contactor, and the combustion process is applied (Post-combustion capture) of the carbon dioxide absorption device. In this paper, we would investigate the effect of the ceramic membrane hydrophobicity to the flux of the carbon dioxide adsorption. To improve the applicability of the ceramic film. We use the dry-wet spinning method with the high temperature sintering process for preparing a ceramic hollow fiber membranes to increase the filling density per unit volume of the membrane. The PESf/Al2O3 ratio of 1:5 was prepared ceramic hollow fibers membrane precursors and investigate the relationship of the different sintering temperature to the membrane pore size and porosity. It can be found that the membrane via the sintering temperature of 1400 °C prepared with the highest porosity of 70%, while the membrane via the sintering temperature of 1600 °C prepared although has a minimum porosity of about 54%, but also has the smallest average pore size of about 0.2 μm. The hydrophilic ceramic hollow fiber membranes which after high-temperature sintering were changed into hydrophobic successfully via the 0.02M FAS modifier. The hydrophobic ceramic hollow fiber membranes with different sintering temperature, the membrane which was prepared via 1400 °C sintering has the highest carbon dioxide adsorption about 4.2 × 10-4 (mole/m2s). The membrane prepared via 1500 °C sintering has the carbon dioxide adsorption about 3.8 × 10-3 (mole/m2s),and the membrane prepared via 1600 °C sintering has the lowest carbon dioxide adsorption about 2.68 × 10-3 (mole/m2s).All of them have reusability and in long time operation, the membrane which was prepared via 1600 °C sintering has the smallest pores and also could operate for three days. After the test, the 1600 °C sintering ceramic hollow fiber membrane was most suitable for the factory.

Keywords: carbon dioxide capture, membrane contactor, ceramic membrane, ceramic hollow fiber membrane

Procedia PDF Downloads 350