Search results for: carbon credit
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3393

Search results for: carbon credit

2553 Nickel Oxide-Nitrogen-Doped Carbon (Ni/NiOx/NC) Derived from Pyrolysis of 2-Aminoterephthalic Acid for Electrocatalytic Oxidation of Ammonia

Authors: Yu-Jen Shih, Juan-Zhang Lou

Abstract:

Nitrogenous compounds, such as NH4+/NH3 and NO3-, have become important contaminants in water resources. Excessive concentration of NH3 leads to eutrophication, which poses a threat to aquatic organisms in the environment. Electrochemical oxidation emerged as a promising water treatment technology, offering advantages such as simplicity, small-scale operation, and minimal reliance on additional chemicals. In this study, a nickel-based metal-organic framework (Ni-MOF) was synthesized using 2-amino terephthalic acid (BDC-NH2) and nickel nitrate. The Ni-MOF was further carbonized as derived nickel oxide and nitrogen-carbon composite, Ni/NiOx/NC. The nickel oxide within the 2D porous carbon texture served as active sites for ammonia oxidation. Results of characterization showed that the Ni-MOF was a hexagonal and flaky nanoparticle. With increasing carbonization temperature, the nickel ions in the organic framework re-crystallized as NiO clusters on the surfaces of the 2D carbon. The electrochemical surface area of Ni/NiOx/NC significantly increased as to improve the efficiency of ammonia oxidation. The phase transition of Ni(OH)2⇌NiOOH at around +0.8 V was the primary mediator of electron transfer. Batch electrolysis was conducted under constant current and constant potential modes. The electrolysis parameters included pyrolysis temperatures, pH, current density, initial feed concentration, and electrode potential. The constant current batch experiments indicated that via carbonization at 800 °C, Ni/NiOx/NC(800) was able to decrease the ammonium nitrogen of 50 mg-N/L to below 1 ppm within 4 hours at a current density of 3 mA/cm2 and pH 11 with negligible oxygenated nitrogen formation. The constant potential experiments confirmed that N2 nitrogen selectivity was enhanced up to 90% at +0.8 V.

Keywords: electrochemical oxidation, nickel oxyhydroxide, metal-organic framework, ammonium, nitrate

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2552 Investigating Nanocrystalline CaF2:Tm for Carbon Beam and Gamma Radiation Dosimetry

Authors: Kanika Sharma, Shaila Bahl, Birendra Singh, Pratik Kumar, S. P. Lochab, A. Pandey

Abstract:

In the present investigation, initially nano-particles of CaF2 were prepared by the chemical co-precipitation method and later the prepared salt was activated by thulium (0.1 mol%) using the combustion technique. The final product was characterized and confirmed by X-Ray diffraction (XRD) and transmission electron microscopy (TEM). Further, the thermoluminescence (TL) properties of the nanophosphor were studied by irradiating it with 1.25 MeV of gamma radiation and 65 MeV of carbon (C6+) ion beam. For gamma rays, two prominent TL peaks were observed with a low temperature peak at around 1070C and a high temperature peak at around 1570C. Furthermore, the nanophosphor maintained a linear TL response for the entire range of studied doses i.e. 10 Gy to 2000 Gy for both the temperature peaks. Moreover, when the nanophosphor was irradiated with 65 MeV of C6+ ion beam the shape and structure of the glow curves remained spectacularly similar and the nanophosphor displayed a linear TL response for the full range of studied fluences i.e. 5*1010 ions/cm2 to 1 *1012 ions/ cm2. Finally, various tests like reproducibility test and batch homogeneity were also carried out to define the final product. Thus, co-precipitation method followed by combustion technique was successful in effectively producing dosimetric grade CaF2:Tm for dosimetry of gamma as well as carbon (C6+) beam.

Keywords: gamma radiation, ion beam, nanocrystalline, radiation dosimetry

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2551 Produce Large Surface Area Activated Carbon from Biomass for Water Treatment

Authors: Rashad Al-Gaashani

Abstract:

The physicochemical activation method was used to produce high-quality activated carbon (AC) with a large surface area of about 2000 m2/g from low-cost and abundant biomass wastes in Qatar, namely date seeds. X-Ray diffraction (XRD), scanning electron spectroscopy (SEM), energy dispersive X-Ray spectroscopy (EDS), and Brunauer-Emmett-Teller (BET) surface area analysis was used to evaluate the AC samples. AC produced from date seeds has a wide range of pores available, including micro- and nano-pores. This type of AC with a well-developed pore structure may be very attractive for different applications, including air and water purification from micro and nano pollutants. Heavy metals iron (III) and copper (II) ions were removed from wastewater using the AC produced using a batch adsorption technique. The AC produced from date seeds biomass wastes shows high removal of heavy metals such as iron (III) ions (100%) and copper (II) ions (97.25%). The highest removal of copper (II) ions (100%) with AC produced from date seeds was found at pH 8, whereas the lowest removal (22.63%) occurred at pH 2. The effect of adsorption time, adsorbent dose, and pH on the removal of heavy metals was studied.

Keywords: activated carbon, date seeds, biomass, heavy metals removal, water treatment

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2550 Factors Influencing the Use of Mobile Phone by Smallholder Farmers in Vegetable Marketing in Fogera District

Authors: Molla Tadesse Lakew

Abstract:

This study was intended to identify the factors influencing the use of mobile phones in vegetable marketing in Fogera district. The use of mobile phones in vegetable marketing and factors influencing mobile phone use were specific objectives of the study. Three kebeles from the Fogera district were selected purposively based on their vegetable production potential. A simple random sampling technique (lottery method) was used to select 153 vegetable producer farmers. Interview schedule and key informants interviews were used to collect primary data. For analyzing the data, descriptive statistics like frequency and percentage, two independent t-tests, and chi-square were used. Furthermore, econometric analysis (binary logistic model) was used to assess the factors influencing mobile phone use for vegetable market information. Contingency coefficient and variance inflation factor were used to check multicollinearity problems between the independent variables. Of 153 respondents, 82 (61.72%) were mobile phone users, while 71 (38.28 %) were mobile phone nonusers. Moreover, the main use of mobile phones in vegetable marketing includes communicating at a distance to save time and minimizing transport costs, getting vegetable marketing price information, identifying markets and buyers to sell the vegetable, deciding when to sell the vegetable, negotiating with buyers for better vegetable prices and for searching of the fast market to avoid from losing of product through perishing. The model result indicated that the level of education, size of land, income, access to credit, and age were significant variables affecting the use of mobile phones in vegetable marketing. It could be recommended to encourage adult education or give training for farmers on how to operate mobile phones and create awareness for the elderly rural farmers as they are able to use the mobile phone for their vegetable marketing. Moreover, farmers should be aware that mobile phones are very important for those who own very small land to get maximum returns from their production. Lastly, providing access to credit and improving and diversifying income sources for the farmers to have mobile phones were recommended to improve the livelihood of farmers.

Keywords: mobile phone, farmers, vegetable marketing, Fogera District

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2549 Thermophysical Properties of Water-Based Carboxylated Multi-Wall Carbon Nanotubes Nanofluids

Authors: Ahmad Amiri, Hamed Khajeh Arzani, Md. Salim Newaz Kazi, Bee Teng Chew

Abstract:

Obviously, the behavior of thermophysical properties of covalently functionalized MWNT-based water nanofluids cannot be predicted from the predicted models. We present a study of the specific heat capacity, effective thermal conductivity, density and viscosity of coolants containing functionalized multi-wall carbon nanotubes (MWNT-COOH) with carboxyl groups at different temperatures. After synthesizing of MWNT-COOH-based water, measurements on the prepared coolants were made at various concentrations by different experimental methods. While thermal conductivity of nanofluids illustrated a significant increase, the specific heat capacity of the samples showed a downward behavior with increasing temperature. The viscosity was investigated in different shear rates and temperatures. Interestingly, the specific heat capacity of all prepared nanofluids was decreased with increasing concentration. Also, the density of the MWNT-COOH-based water nanofluids increased and decreased smoothly with increasing MWNT-COOH concentration and temperature, respectively.

Keywords: carbon nanotubes, coolant, heat capacity, density, viscosity, thermal conductivity

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2548 Immuno-field Effect Transistor Using Carbon Nanotubes Network – Based for Human Serum Albumin Highly Sensitive Detection

Authors: Muhamad Azuddin Hassan, Siti Shafura Karim, Ambri Mohamed, Iskandar Yahya

Abstract:

Human serum albumin plays a significant part in the physiological functions of the human body system (HSA).HSA level monitoring is critical for early detection of HSA-related illnesses. The goal of this study is to show that a field effect transistor (FET)-based immunosensor can assess HSA using high aspect ratio carbon nanotubes network (CNT) as a transducer. The CNT network were deposited using air brush technique, and the FET device was made using a shadow mask process. Field emission scanning electron microscopy and a current-voltage measurement system were used to examine the morphology and electrical properties of the CNT network, respectively. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy were used to confirm the surface alteration of the CNT. The detection process is based on covalent binding interactions between an antibody and an HSA target, which resulted in a change in the manufactured biosensor's drain current (Id).In a linear range between 1 ng/ml and 10zg/ml, the biosensor has a high sensitivity of 0.826 mA (g/ml)-1 and a LOD value of 1.9zg/ml.HSA was also identified in a genuine serum despite interference from other biomolecules, demonstrating the CNT-FET immunosensor's ability to quantify HSA in a complex biological environment.

Keywords: carbon nanotubes network, biosensor, human serum albumin

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2547 Vibration Behavior of Nanoparticle Delivery in a Single-Walled Carbon Nanotube Using Nonlocal Timoshenko Beam Theory

Authors: Haw-Long Lee, Win-Jin Chang, Yu-Ching Yang

Abstract:

In the paper, the coupled equation of motion for the dynamic displacement of a fullerene moving in a (10,10) single-walled carbon nanotube (SWCNT) is derived using nonlocal Timoshenko beam theory, including the effects of rotary inertia and shear deformation. The effects of confined stiffness between the fullerene and nanotube, foundation stiffness, and nonlocal parameter on the dynamic behavior are analyzed using the Runge-Kutta Method. The numerical solution is in agreement with the analytical result for the special case. The numerical results show that increasing the confined stiffness and foundation stiffness decrease the dynamic displacement of SWCNT. However, the dynamic displacement increases with increasing the nonlocal parameter. In addition, result using the Euler beam theory and the Timoshenko beam theory are compared. It can be found that ignoring the effects of rotary inertia and shear deformation leads to an underestimation of the displacement.

Keywords: single-walled carbon nanotube, nanoparticle delivery, Nonlocal Timoshenko beam theory, Runge-Kutta Method, Van der Waals force

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2546 Effect of Urea Deep Placement Technology Adoption on the Production Frontier: Evidence from Irrigation Rice Farmers in the Northern Region of Ghana

Authors: Shaibu Baanni Azumah, William Adzawla

Abstract:

Rice is an important staple crop, with current demand higher than the domestic supply in Ghana. This has led to a high and unfavourable import bill. Therefore, recent policies and interventions in the agricultural sub-sector aim at promoting various improved agricultural technologies in order to improve domestic production and reduce the importation of rice. In this study, we examined the effect of the adoption of Urea Deep Placement (UDP) technology by rice farmers on the position of the production frontier. This involved 200 farmers selected through a multi stage sampling technique in the Northern region of Ghana. A Cobb-Douglas stochastic frontier model was fitted. The result showed that the adoption of UDP technology shifts the output frontier outward and also move the farmers closer to the frontier. Farmers were also operating under diminishing returns to scale which calls for redress. Other factors that significantly influenced rice production were farm size, labour, use of certified seeds and NPK fertilizer. Although there was an opportunity for improvement, the farmers were highly efficient (92%), compared to previous studies. Farmers’ efficiency was improved through increased education, household size, experience, access to credit, and lack of extension service provision by MoFA. The study recommends the revision of Ghana’s agricultural policy to include the UDP technology. Agricultural Extension officers of the Ministry of Food and Agriculture (MoFA) should be trained on the UDP technology to support IFDC’s drive to improve adoption by rice farmers. Rice farmers are also encouraged to expand their farm lands, improve plant population, and also increase the usage of fertilizer to improve yields. Mechanisms through which credit can be made easily accessible and effectively utilised should be identified and promoted.

Keywords: efficiency, rice farmers, stochastic frontier, UDP technology

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2545 Carbon Nanotube Field Effect Transistor - a Review

Authors: P. Geetha, R. S. D. Wahida Banu

Abstract:

The crowning advances in Silicon based electronic technology have dominated the computation world for the past decades. The captivating performance of Si devices lies in sustainable scaling down of the physical dimensions, by that increasing device density and improved performance. But, the fundamental limitations due to physical, technological, economical, and manufacture features restrict further miniaturization of Si based devices. The pit falls are due to scaling down of the devices such as process variation, short channel effects, high leakage currents, and reliability concerns. To fix the above-said problems, it is needed either to follow a new concept that will manage the current hitches or to support the available concept with different materials. The new concept is to design spintronics, quantum computation or two terminal molecular devices. Otherwise, presently used well known three terminal devices can be modified with different materials that suits to address the scaling down difficulties. The first approach will occupy in the far future since it needs considerable effort; the second path is a bright light towards the travel. Modelling paves way to know not only the current-voltage characteristics but also the performance of new devices. So, it is desirable to model a new device of suitable gate control and project the its abilities towards capability of handling high current, high power, high frequency, short delay, and high velocity with excellent electronic and optical properties. Carbon nanotube became a thriving material to replace silicon in nano devices. A well-planned optimized utilization of the carbon material leads to many more advantages. The unique nature of this organic material allows the recent developments in almost all fields of applications from an automobile industry to medical science, especially in electronics field-on which the automation industry depends. More research works were being done in this area. This paper reviews the carbon nanotube field effect transistor with various gate configurations, number of channel element, CNT wall configurations and different modelling techniques.

Keywords: array of channels, carbon nanotube field effect transistor, double gate transistor, gate wrap around transistor, modelling, multi-walled CNT, single-walled CNT

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2544 Impact of Activated Carbon and Magnetic Field in Slow Sand Filter on Water Purification for Rural Dwellers

Authors: Baiyeri R. M, Oloriegbe Y. A., Saad A. O., Yusuf, K. O.

Abstract:

Most farmers that produce food crops in Nigeria live in rural areas where potable water is not available. The farmers in some areas have problem of water borne diseases which could affect their health and could lead to death. This study was conducted to determine the impact of incorporating Granular Activated Carbon(GAC) and Magnetic Field(MF) in Slow Sand Filter(SSF) on the purification of water for rural dwellers. The SSF was developed using PVC pipe with diameter 152.4 mm and 1100 mm long, with layers of fine sand with size 0.25 mm and 350 mm depth, followed by GAC 10 mm size and 100 mm depth, fine sand 0.25mm with 500 mm depth and gravel grain size 10-14 mm and 100 mm depth. The SSF was kept moist for 21 days for biofilm layer (schmutzdecke) to fully develop, which is essential for trapping bacteria. Two SSFs fabricated consist of SSF+GAC as Filter 1, SSF+GAC+MF as Filter 2 and Control (Raw water without passing through filter. Water samples were collected from the filter and analyzed. The flow rate of Filter was 25 litres/h Total bacteria counts(TBC) for Filter 1 and Filter 2 and control were 2.4, 4.6 and 8.1 cfu/mg, respectively. Total coliform count for Filter 1 and Filter 2 and control were 1.7, 3.0 and 6.4 cfu/100mL, respectively. The filters reduced water hardness, turbidity, lead, copper, electrical conductivity and TBC by 53.13-73.44% but increased pH from 5.8 to 7.1-7.3. SSF is recommended for water purification in the rural areas.

Keywords: magnetised water, sow sand filter, portable water, activated carbon

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2543 Examining the Missing Feedback Link in Environmental Kuznets Curve Hypothesis

Authors: Apra Sinha

Abstract:

The inverted U-shaped Environmental Kuznets curve (EKC) demonstrates(pollution-income relationship)that initially the pollution and environmental degradation surpass the level of income per capita; however this trend reverses since at the higher income levels, economic growth initiates environmental upgrading. However, what effect does increased environmental degradation has on growth is the missing feedback link which has not been addressed in the EKC hypothesis. This paper examines the missing feedback link in EKC hypothesis in Indian context by examining the casual association between fossil fuel consumption, carbon dioxide emissions and economic growth for India. Fossil fuel consumption here has been taken as a proxy of driver of economic growth. The casual association between the aforementioned variables has been analyzed using five interventions namely 1) urban development for which urbanization has been taken proxy 2) industrial development for which industrial value added has been taken proxy 3) trade liberalization for which sum of exports and imports as a share of GDP has been taken as proxy 4)financial development for which a)domestic credit to private sector and b)net foreign assets has been taken as proxies. The choice of interventions for this study has been done keeping in view the economic liberalization perspective of India. The main aim of the paper is to investigate the missing feedback link for Environmental Kuznets Curve Hypothesis before and after incorporating the intervening variables. The period of study is from 1971 to 2011 as it covers pre and post liberalization era in India. All the data has been taken from World Bank country level indicators. The Johansen and Juselius cointegration testing methodology and Error Correction based Granger causality have been applied on all the variables. The results clearly show that out of five interventions, only in two interventions the missing feedback link is being addressed. This paper can put forward significant policy implications for environment protection and sustainable development.

Keywords: environmental Kuznets curve hypothesis, fossil fuel consumption, industrialization, trade liberalization, urbanization

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2542 The Proton Flow Battery for Storing Renewable Energy: Hydrogen Storage Capacity of Selected Activated Carbon Electrodes Made from Brown Coal

Authors: Amandeep Singh Oberoi, John Andrews, Alan L. Chaffee, Lachlan Ciddor

Abstract:

Electrochemical storage of hydrogen in activated carbon electrodes as part of a reversible fuel cell offers a potentially attractive option for storing surplus electrical energy from inherently variable solar and wind energy resources. Such a system – which we have called a proton flow battery – promises to have roundtrip energy efficiency comparable to lithium ion batteries, while having higher gravimetric and volumetric energy densities. Activated carbons with high internal surface area, high pore volume, light weight and easy availability have attracted considerable research interest as a solid-state hydrogen storage medium. This paper compares the physical characteristics and hydrogen storage capacities of four activated carbon electrodes made by different methods from brown coal. The fabrication methods for these samples are explained. Their proton conductivity was measured using electrochemical impedance spectroscopy, and their hydrogen storage capacity by galvanostatic charging and discharging in a three-electrode electrolytic cell with 1 mol sulphuric acid as electrolyte. The highest hydrogen storage capacity obtained was 1.29 wt%, which compares favourably with metal hydrides used in commercially available solid-state hydrogen storages. The hydrogen storage capacity of the samples increased monotonically with increasing BET surface area (calculated from CO2 adsorption method). The results point the way towards selecting high-performing electrodes for proton flow batteries that the competitiveness of this energy storage technology.

Keywords: activated carbon, electrochemical hydrogen storage, proton flow battery, proton conductivity

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2541 Effect of Nanofibers on the Behavior of Cement Mortar and Concrete

Authors: Mostafa Osman, Ata El-Kareim Shoeib

Abstract:

The main objective of this paper is study the influence of carbon nano-tubes fibers and nano silica fibers on the characteristic compressive strength and flexural strength on concrete and cement mortar. Twelve tested specimens were tested with square section its dimensions (40*40*160) mm, divided into four groups. The first and second group studied the effect of carbon nano-tubes (CNTs) fiber with different percentage equal to 0.0, 0.11 %, 0.22 %, and 0.33 % by weight of cement and effect of nano-silica (nS) fibers with different percentages equal to 0.0, 1.0 %, 2.0 %, and 3.0 % by weight of cement on the cement mortar. The third and fourth groups studied the effect of CNTs fiber with different percentage equal to 0.0 %, 0.11 %, and 0.22 % by weight of cement, and effect of nS fibers with different percentages were equal to 0.0 %, 1.0%, and 2.0 % by weight of cement on the concrete. The compressive strength and flexural strength at 7, 28, and 90 days is determined. From analysis of tested results concluded that the nano-fiber is more effective when used with cement mortar than that of used with concrete because of increasing the surface area, decreasing the pore and the collection of nano-fiber. And also by adding nano-fiber the improvement of flexural strength of concrete and cement mortar is more than improvement of compressive strength.

Keywords: carbon nano-tubes (CNTs) fibres, nano-silica (nS) fibres, compressive strength, flexural strength

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2540 Storage of Organic Carbon in Chemical Fractions in Acid Soil as Influenced by Different Liming

Authors: Ieva Jokubauskaite, Alvyra Slepetiene, Danute Karcauskiene, Inga Liaudanskiene, Kristina Amaleviciute

Abstract:

Soil organic carbon (SOC) is the key soil quality and ecological stability indicator, therefore, carbon accumulation in stable forms not only supports and increases the organic matter content in the soil, but also has a positive effect on the quality of soil and the whole ecosystem. Soil liming is one of the most common ways to improve the carbon sequestration in the soil. Determination of the optimum intensity and combinations of liming in order to ensure the optimal carbon quantitative and qualitative parameters is one of the most important tasks of this work. The field experiments were carried out at the Vezaiciai Branch of Lithuanian Research Centre for Agriculture and Forestry (LRCAF) during the 2011–2013 period. The effect of liming with different intensity (at a rate 0.5 every 7 years and 2.0 every 3-4 years) was investigated in the topsoil of acid moraine loam Bathygleyic Dystric Glossic Retisol. Chemical analyses were carried out at the Chemical Research Laboratory of Institute of Agriculture, LRCAF. Soil samples for chemical analyses were taken from the topsoil after harvesting. SOC was determined by the Tyurin method modified by Nikitin, measuring with spectrometer Cary 50 (VARIAN) at 590 nm wavelength using glucose standards. SOC fractional composition was determined by Ponomareva and Plotnikova version of classical Tyurin method. Dissolved organic carbon (DOC) was analyzed using an ion chromatograph SKALAR in water extract at soil-water ratio 1:5. Spectral properties (E4/E6 ratio) of humic acids were determined by measuring the absorbance of humic and fulvic acids solutions at 465 and 665 nm. Our study showed a negative statistically significant effect of periodical liming (at 0.5 and 2.0 liming rates) on SOC content in the soil. The content of SOC was 1.45% in the unlimed treatment, while in periodically limed at 2.0 liming rate every 3–4 years it was approximately by 0.18 percentage points lower. It was revealed that liming significantly decreased the DOC concentration in the soil. The lowest concentration of DOC (0.156 g kg-1) was established in the most intensively limed (2.0 liming rate every 3–4 years) treatment. Soil liming exerted an increase of all humic acids and fulvic acid bounded with calcium fractions content in the topsoil. Soil liming resulted in the accumulation of valuable humic acids. Due to the applied liming, the HR/FR ratio, indicating the quality of humus increased to 1.08 compared with that in unlimed soil (0.81). Intensive soil liming promoted the formation of humic acids in which groups of carboxylic and phenolic compounds predominated. These humic acids are characterized by a higher degree of condensation of aromatic compounds and in this way determine the intensive organic matter humification processes in the soil. The results of this research provide us with the clear information on the characteristics of SOC change, which could be very useful to guide the climate policy and sustainable soil management.

Keywords: acid soil, carbon sequestration, long–term liming, soil organic carbon

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2539 Modifications in Design of Lap Joint of Fiber Metal Laminates

Authors: Shaher Bano, Samia Fida, Asif Israr

Abstract:

The continuous development and exploitation of materials and designs have diverted the attention of the world towards the use of robust composite materials known as fiber-metal laminates in many high-performance applications. The hybrid structure of fiber metal laminates makes them a material of choice for various applications such as aircraft skin panels, fuselage floorings, door panels and other load bearing applications. The synergistic effect of properties of metals and fibers reinforced laminates are responsible for their high damage tolerance as the metal element provides better fatigue and impact properties, while high stiffness and better corrosion properties are inherited from the fiber reinforced matrix systems. They are mostly used as a layered structure in different joint configurations such as lap and but joints. The FML layers are usually bonded with each other using either mechanical fasteners or adhesive bonds. This research work is also focused on modification of an adhesive bonded joint as a single lap joint of carbon fibers based CARALL FML has been modified to increase interlaminar shear strength and avoid delamination. For this purpose different joint modification techniques such as the introduction of spews and shoulder to modify the bond shape and use of nanofillers such as carbon nano-tubes as a reinforcement in the adhesive materials, have been utilized to improve shear strength of lap joint of the adhesively bonded FML layers. Both the simulation and experimental results showed that lap joint with spews and shoulders configuration have better properties due to stress distribution over a large area at the corner of the joint. The introduction of carbon nanotubes has also shown a positive effect on shear stress and joint strength as they act as reinforcement in the adhesive bond material.

Keywords: adhesive joint, Carbon Reinforced Aluminium Laminate (CARALL), fiber metal laminates, spews

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2538 An Innovation and Development System for a New Hybrid Composite Technology in Aerospace Industry

Authors: M. Fette, J. P. Wulfsberg, A. Herrmann, R. H. Ladstaetter

Abstract:

Present and future lightweight design represents an important key to successful implementation of energy-saving, fuel-efficient and environmentally friendly means of transport in the aerospace and automotive industry. In this context the use of carbon fibre reinforced plastics (CFRP) which are distinguished by their outstanding mechanical properties at relatively low weight, promise significant improvements. Due to the reduction of the total mass, with the resulting lowered fuel or energy consumption and CO2 emissions during the operational phase, commercial aircraft and future vehicles will increasingly be made of CFRP. An auspicious technology for the efficient and economic production of high performance thermoset composites and hybrid structures for future lightweight applications is the combination of carbon fibre sheet moulding compound (SMC), tailored continuous carbon fibre reinforcements and metallic components in a one-shot pressing and curing process. This paper deals with a new hybrid composite technology for aerospace industries, which was developed with the help of a universal innovation and development system. This system supports the management of idea generation, the methodical development of innovative technologies and the achievement of the industrial readiness of these technologies.

Keywords: development system, hybrid composite, innovation system, prepreg, sheet moulding compound

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2537 Female Entrepreneurship in Transitional Economies: An In-Depth Comparative Study about Challenges Facing Female Entrepreneurs in Nigeria and Egypt

Authors: Dina Mohamed Ayman, Rafieu Akin

Abstract:

In an attempt to increase the female total entrepreneurial activities (TEA) within Egypt and Nigeria, this paper aims to investigate the challenges facing female entrepreneurs operating in Egypt, in relative to Nigeria. In this regard, both researchers undertook a qualitative approach due to the scarcity of the literature reviewed on the topic; in those particular countries, and as an in-depth comparative mode. Therefore, ten Egyptian entrepreneurs in relative to ten Nigerian entrepreneurs were in-depth investigated. The research findings prove that female entrepreneurs face complex problems for being both gender and country-specific. Regarding the gender-specific obstacles, the work/life imbalance due to the scarcity of child-care nurseries and the prevalence of the gender-role division while performing the house chores rather than the concept of co-operation, acted as a main source of cultural challenge because women are considered mostly as 'housewives'. However, interestingly, this specific gender-discrimination challenge is proven to have no grounded effect in terms of the business-establishment and daily dealings neither in Egypt nor Nigeria, as one of the sample exclaimed 'as long as you pay, then no gender difference is set on the table'. Other country-specific challenges facing female entrepreneurs, lied in, the aggregate weak entrepreneurial framework governing both countries, also, women faced the difficulty of access to financial institutions with collateral requirements that are usually "hardly to be met", besides, the absence of the "micro-credit-Grameen-banks" concept. As well, the scarcity of incubators and business training centers providing network, consultancy and well-trained workforce to female entrepreneurs constitute a major hurdle for women entrepreneurs operating in both countries. Finally, this paper will conclude the research by offering a set of public-policy recommendations to pave the way for females to choose self-employment as a career path.

Keywords: entrepreneurship, female entrepreneurship, obstacles, framework conditions, culture, micro-credit

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2536 Metallic Coating for Carbon Fiber Reinforced Polymer Matrix Composite Substrate

Authors: Amine Rezzoug, Said Abdi, Nadjet Bouhelal, Ismail Daoud

Abstract:

This paper investigates the application of metallic coatings on high fiber volume fraction carbon/epoxy polymer matrix composites. For the grip of the metallic layer, a method of modifying the surface of the composite by introducing a mixture of copper and steel powder (filler powders) which can reduce the impact of thermal spray particles. The powder was introduced to the surface at the time of the forming. Arc spray was used to project the zinc coating layer. The substrate was grit blasted to avoid poor adherence. The porosity, microstructure, and morphology of layers are characterized by optical microscopy, SEM and image analysis. The samples were studied also in terms of hardness and erosion resistance. This investigation did not reveal any visible evidence damage to the substrates. The hardness of zinc layer was about 25.94 MPa and the porosity was around (∼6.70%). The erosion test showed that the zinc coating improves the resistance to erosion. Based on the results obtained, we can conclude that thermal spraying allows the production of protective coating on PMC. Zinc coating has been identified as a compatible material with the substrate. The filler powders layer protects the substrate from the impact of hot particles and allows avoiding the rupture of brittle carbon fibers.

Keywords: arc spray, coating, composite, erosion

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2535 Corrosive Bacteria Attached to Carbon Steel Used in Oil and Gas Company

Authors: Hadjer Didouh, Mohammed Hadj Melliani, Izzeddine Sameut Bouhaik

Abstract:

Microbiologically influenced corrosion (MIC) is a major cause of pipeline failure in the oil and gas industry, particularly affecting carbon steel, which is widely used for its cost-effectiveness and mechanical properties. This study investigates the adhesion of sulfate-reducing bacteria (SRB) and other corrosive microbial species on API 5L X52 carbon steel in crude oil and injection water environments. Experimental results showed that after 72 hours of exposure, biofilm formed extensively, leading to significant corrosion rates. Weight loss measurements indicated a corrosion rate of 0.39 mm/year, with localized pitting observed at depths reaching 120 μm. Electrochemical impedance spectroscopy (EIS) revealed a drastic decrease in charge transfer resistance, from 1200 Ω/cm² for sterile samples to 240 Ω/cm² in the presence of SRB biofilm. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses confirmed the presence of iron sulfide deposits, indicating active bacterial colonization and biofilm-induced pitting corrosion. This study highlights the severe impact of MIC on pipeline infrastructure, emphasizing the need for efficient microbial control strategies. Furthermore, the results provide a framework for the development of enhanced protective coatings and environmentally friendly biocides to mitigate the economic and environmental risks associated with MIC in oilfield operations in Algeria.

Keywords: MIC, corrosion, bacteria, API 5L X52

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2534 Kinetic and Mechanistic Study on the Degradation of Typical Pharmaceutical and Personal Care Products in Water by Using Carbon Nanodots/C₃N₄ Composite and Ultrasonic Irradiation

Authors: Miao Yang

Abstract:

PPCPs (pharmaceutical and personal care products) in water, as an environmental pollutant, becomes an issue of increasing concern. Therefore, the techniques for degradation of PPCPs has been a hotspot in water pollution control field. Since there are several disadvantages for common degradation techniques of PPCPs, such as low degradation efficiency for certain PPCPs (ibuprofen and Carbamazepine) this proposal will adopt a combined technique by using CDs (carbon nanodots)/C₃N₄ composite and ultrasonic irradiation to mitigate or overcome these shortages. There is a significant scientific problem that the mechanism including PPCPs, major reactants, and interfacial active sites is not clear yet in the study of PPCPs degradation. This work aims to solve this problem by using both theoretical and experimental methodologies. Firstly, optimized parameters will be obtained by evaluating the kinetics and oxidation efficiency under different conditions. The competition between H₂O₂ and PPCPs with HO• will be elucidated, after which the degradation mechanism of PPCPs by the synergy of CDs/C₃N₄ composite and ultrasonic irradiation will be proposed. Finally, a sonolysis-adsorption-catalysis coupling mechanism will be established which is the theoretical basis and technical support for developing new efficient degradation techniques for PPCPs in the future.

Keywords: carbon nanodots/C₃N₄, pharmaceutical and personal care products, ultrasonic irradiation, hydroxyl radical, heterogeneous catalysis

Procedia PDF Downloads 173
2533 Building Carbon Footprint Comparison between Building Permit, as Built, as Built with Circular Material Usage

Authors: Kadri-Ann Kertsmik, Martin Talvik, Kimmo Lylykangas, Simo Ilomets, Targo Kalamees

Abstract:

This study compares the building carbon footprint (CF) values for a case study of a private house located in a cold climate, using the Level(s) methodology. It provides a framework for measuring the environmental performance of buildings throughout their life cycle, taking into account various factors. The study presents the results of the three scenarios, comparing their carbon emissions and highlighting the benefits of circular material usage. The construction process was thoroughly documented, and all materials and components (including minuscule mechanical fasteners, each meter of cable, a kilogram of mortar, and the component of HVAC systems, among other things) delivered to the construction site were noted. Transportation distances of each delivery, the fuel consumption of construction machines, and electricity consumption for temporary heating and electrical tools were also monitored. Using the detailed data on material and energy resources, the CF was calculated for two scenarios: one where circular material usage was applied and another where virgin materials were used instead of reused ones. The results were compared with the CF calculated based on the building permit design model using the Level(s) methodology. To study the range of possible results in the early stage of CF assessment, the same building permit design was given to several experts. Results showed that embodied carbon values for a built scenario were significantly lower than the values predicted by the building permit stage as a result of more precise material quantities, as the calculation methodology is designed to overestimate the CF. Moreover, designers made an effort to reduce the building's CF by reusing certain materials such as ceramic tiles, lightweight concrete blocks, and timber during the construction process. However, in a cold climate context where operational energy (B6) continues to dominate, the total building CF value changes between the three scenarios were less significant. The calculation for the building permit project was performed by several experts, and CF results were in the same range. It alludes that, for the first estimation of preliminary building CF, using average values proves to be an appropriate method for the Estonian national carbon footprint estimation phase during building permit application. The study also identified several opportunities for reducing the carbon footprint of the building, such as reusing materials from other construction sites, preferring local material producers, and reducing wastage on site. The findings suggest that using circular materials can significantly reduce the carbon footprint of buildings. Overall, the study highlights the importance of using a comprehensive approach to measure the environmental performance of buildings, taking into account both the project and the actually built house. It also emphasises the need for ongoing monitoring for designing the building and construction site waste. The study also gives some examples of how to enable future circularity of building components and materials, e.g., building in layers, using wood as untreated, etc.

Keywords: carbon footprint, circular economy, sustainable construction, level(s) methodology

Procedia PDF Downloads 80
2532 The Discriminate Analysis and Relevant Model for Mapping Export Potential

Authors: Jana Gutierez Chvalkovska, Michal Mejstrik, Matej Urban

Abstract:

There are pending discussions over the mapping of country export potential in order to refocus export strategy of firms and its evidence-based promotion by the Export Credit Agencies (ECAs) and other permitted vehicles of governments. In this paper we develop our version of an applied model that offers “stepwise” elimination of unattractive markets. We modify and calibrate the model for the particular features of the Czech Republic and specific pilot cases where we apply an individual approach to each sector.

Keywords: export strategy, modeling export, calibration, export promotion

Procedia PDF Downloads 494
2531 Optimizing the Pair Carbon Xerogels-Electrolyte for High Performance Supercapacitors

Authors: Boriana Karamanova, Svetlana Veleva, Luybomir Soserov, Ana Arenillas, Francesco Lufrano, Antonia Stoyanova

Abstract:

Supercapacitors have received a lot of research attention and are promising energy storage devices due to their high power and long cycle life. In order to developed an advanced device with significant capacity for storing charge and cheap carbon materials, efforts must focus not only on improving synthesis by controlling the morphology and pore size but also on improving electrode-electrolyte compatibility of the resulting systems. The present study examines the relationship between the surface chemistry of two activated carbon xerogels, the electrolyte type, and the electrochemical properties of supercapacitors. Activated carbon xerogels were prepared by varying the initial pH of the resorcinol-formaldehyde aqueous solution. The materials produced are physicochemical characterized by DTA/TGA, porous characterization, and SEM analysis. The carbon xerogel based electrodes were prepared by spreading over glass plate a slurry containing the carbon gel, graphite, and poly vinylidene difluoride (PVDF) binder. The layer formed was dried consecutively at different temperatures and then detached by water. After, the layer was dried again to improve its mechanical stability. The developed electrode materials and the Aquivion® E87-05S membrane (Solvay Specialty Polymers), socked in Na2SO4 as a polymer electrolyte, were used to assembly the solid-state supercapacitor. Symmetric supercapacitor cells composed by same electrodes and 1 M KOH electrolytes are also assembled and tested for comparison. The supercapacitor performances are verified by different electrochemical methods - cyclic voltammetry, galvanostatic charge/discharge measurements, electrochemical impedance spectroscopy, and long-term durability tests in neutral and alkaline electrolytes. Specific capacitances, energy, and power density, energy efficiencies, and durability were compared into studied supercapacitors. Ex-situ physicochemical analyses on the synthesized materials have also been performed, which provide information about chemical and structural changes in the electrode morphology during charge / discharge durability tests. They are discussed on the basis of electrode-electrolyte interaction. The obtained correlations could be of significance in order to design sustainable solid-state supercapacitors with high power and energy density. Acknowledgement: This research is funded by the Ministry of Education and Science of Bulgaria under the National Program "European Scientific Networks" (Agreement D01-286 / 07.10.2020, D01-78/30.03.2021). Authors gratefully acknowledge.

Keywords: carbon xerogel, electrochemical tests, neutral and alkaline electrolytes, supercapacitors

Procedia PDF Downloads 133
2530 Identification of Rice Quality Using Gas Sensors and Neural Networks

Authors: Moh Hanif Mubarok, Muhammad Rivai

Abstract:

The public's response to quality rice is very high. So it is necessary to set minimum standards in checking the quality of rice. Most rice quality measurements still use manual methods, which are prone to errors due to limited human vision and the subjectivity of testers. So, a gas detection system can be a solution that has high effectiveness and subjectivity for solving current problems. The use of gas sensors in testing rice quality must pay attention to several parameters. The parameters measured in this research are the percentage of rice water content, gas concentration, output voltage, and measurement time. Therefore, this research was carried out to identify carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄) gases in rice quality using a series of gas sensors using the Neural Network method.

Keywords: carbon dioxide, dinitrogen oxide, methane, semiconductor gas sensor, neural network

Procedia PDF Downloads 33
2529 Simultaneous Adsorption and Characterization of NOx and SOx Emissions from Power Generation Plant on Sliced Porous Activated Carbon Prepared by Physical Activation

Authors: Muhammad Shoaib, Hassan M. Al-Swaidan

Abstract:

Air pollution has been a major challenge for the scientists today, due to the release of toxic emissions from various industries like power plants, desalination plants, industrial processes and transportation vehicles. Harmful emissions into the air represent an environmental pressure that reflects negatively on human health and productivity, thus leading to a real loss in the national economy. Variety of air pollutants in the form of carbon oxides, hydrocarbons, nitrogen oxides, sulfur oxides, suspended particulate material etc. are present in air due to the combustion of different types of fuels like crude oil, diesel oil and natural gas. Among various pollutants, NOx and SOx emissions are considered as highly toxic due to its carcinogenicity and its relation with various health disorders. In Kingdom of Saudi Arabia electricity is generated by burning of crude, diesel or natural gas in the turbines of electricity stations. Out of these three, crude oil is used extensively for electricity generation. Due to the burning of the crude oil there are heavy contents of gaseous pollutants like sulfur dioxides (SOx) and nitrogen oxides (NOx), gases which are ultimately discharged in to the environment and is a serious environmental threat. The breakthrough point in case of lab studies using 1 gm of sliced activated carbon adsorbant comes after 20 and 30 minutes for NOx and SOx, respectively, whereas in case of PP8 plant breakthrough point comes in seconds. The saturation point in case of lab studies comes after 100 and 120 minutes and for actual PP8 plant it comes after 60 and 90 minutes for NOx and SOx adsorption, respectively. Surface characterization of NOx and SOx adsorption on SAC confirms the presence of peaks in the FT-IR spectrum. CHNS study verifies that the SAC is suitable for NOx and SOx along with some other C and H containing compounds coming out from stack emission stream from the turbines of a power plant.

Keywords: activated carbon, flue gases, NOx and SOx adsorption, physical activation, power plants

Procedia PDF Downloads 342
2528 Medium Design and Optimization for High Β-Galactosidase Producing Microbial Strains from Dairy Waste through Fermentation

Authors: Ashish Shukla, K. P. Mishra, Pushplata Tripathi

Abstract:

This paper investigates the production and optimization of β-galactosidase enzyme using synthetic medium by isolated wild strains (S1, S2) mutated strains (M1, M2) through SSF and SmF. Among the different cell disintegration methods used, the highest specific activity was obtained when the cells were permeabilized using isoamyl alcohol. Wet lab experiments were performed to investigate the effects of carbon and nitrogen substrates present in Vogel’s medium on β-galactosidase enzyme activity using S1, S2, and M1, M2 strains through SSF. SmF experiments were performed for effects of carbon and nitrogen sources in YLK2Mg medium on β-galactosidase enzyme activity using S1, S2 and M1, M2 strains. Effect of pH on β-galactosidase enzyme production was also done using S1, S2, and M1, M2 strains. Results were found to be very appreciable in all the cases.

Keywords: β-galactosidase, cell disintegration, permeabilized, SSF, SmF

Procedia PDF Downloads 266
2527 Experimental Simulations of Aerosol Effect to Landfalling Tropical Cyclones over Philippine Coast: Virtual Seeding Using WRF Model

Authors: Bhenjamin Jordan L. Ona

Abstract:

Weather modification is an act of altering weather systems that catches interest on scientific studies. Cloud seeding is a common form of weather alteration. On the same principle, tropical cyclone mitigation experiment follows the methods of cloud seeding with intensity to account for. This study will present the effects of aerosol to tropical cyclone cloud microphysics and intensity. The framework of Weather Research and Forecasting (WRF) model incorporated with Thompson aerosol-aware scheme is the prime host to support the aerosol-cloud microphysics calculations of cloud condensation nuclei (CCN) ingested into the tropical cyclones before making landfall over the Philippine coast. The coupled microphysical and radiative effects of aerosols will be analyzed using numerical data conditions of Tropical Storm Ketsana (2009), Tropical Storm Washi (2011), and Typhoon Haiyan (2013) associated with varying CCN number concentrations per simulation per typhoon: clean maritime, polluted, and very polluted having 300 cm-3, 1000 cm-3, and 2000 cm-3 aerosol number initial concentrations, respectively. Aerosol species like sulphates, sea salts, black carbon, and organic carbon will be used as cloud nuclei and mineral dust as ice nuclei (IN). To make the study as realistic as possible, investigation during the biomass burning due to forest fire in Indonesia starting October 2015 as Typhoons Mujigae/Kabayan and Koppu/Lando had been seeded with aerosol emissions mainly comprises with black carbon and organic carbon, will be considered. Emission data that will be used is from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS). The physical mechanism/s of intensification or deintensification of tropical cyclones will be determined after the seeding experiment analyses.

Keywords: aerosol, CCN, IN, tropical cylone

Procedia PDF Downloads 293
2526 Mapping the Core Processes and Identifying Actors along with Their Roles, Functions and Linkages in Trout Value Chain in Kashmir, India

Authors: Stanzin Gawa, Nalini Ranjan Kumar, Gohar Bilal Wani, Vinay Maruti Hatte, A. Vinay

Abstract:

Rainbow trout (Oncorhynchus mykiss) and Brown trout (Salmo trutta fario) are the two species of trout which were once introduced by British in waters of Kashmir has well adapted to favorable climatic conditions. Cold water fisheries are one of the emerging sectors in Kashmir valley and trout holds an important place Jammu and Kashmir fisheries. Realizing the immense potential of trout culture in Kashmir region, the state fisheries department started privatizing trout culture under the centrally funded scheme of RKVY in which they provide 80 percent subsidy for raceway construction and supply of feed and seed for the first year since 2009-10 and at present there are 362 private trout farms. To cater the growing demand for trout in the valley, it is important to understand the bottlenecks faced in the propagation of trout culture. Value chain analysis provides a generic framework to understand the various activities and processes, mapping and studying linkages is first step that needs to be done in any value chain analysis. In Kashmir, it is found that trout hatcheries play a crucial role in insuring the continuous supply of trout seed in valley. Feed is most limiting factor in trout culture and the farmer has to incur high cost in payment and in the transportation of feed from the feed mill to farm. Lack of aqua clinic in the Kashmir valley needs to be addressed. Brood stock maintenance, breeding and seed production, technical assistance to private farmer, extension services have to be strengthened and there is need to development healthier environment for new entrepreneurs. It was found that trout farmers do not avail credit facility as there is no well define credit scheme for fisheries in the state. The study showed weak institutional linkages. Research and development should focus more on applied science rather than basic science.

Keywords: trout, Kashmir, value chain, linkages, culture

Procedia PDF Downloads 398
2525 Effect of Laser Ablation OTR Films and High Concentration Carbon Dioxide for Maintaining the Freshness of Strawberry ‘Maehyang’ for Export in Modified Atmosphere Condition

Authors: Hyuk Sung Yoon, In-Lee Choi, Min Jae Jeong, Jun Pill Baek, Ho-Min Kang

Abstract:

This study was conducted to improve storability by using suitable laser ablation oxygen transmission rate (OTR) films and effectiveness of high carbon dioxide at strawberry 'Maehyang' for export. Strawberries were grown by hydroponic system in Gyeongsangnam-do province. These strawberries were packed by different laser ablation OTR films (Daeryung Co., Ltd.) such as 1,300 cc, 20,000 cc, 40,000 cc, 80,000 cc, and 100,000 cc•m-2•day•atm. And CO2 injection (30%) treatment was used 20,000 cc•m-2•day•atm OTR film and perforated film was as a control. Temperature conditions were applied simulated shipping and distribution conditions from Korea to Singapore, there were stored at 3 ℃ (13 days), 10 ℃ (an hour), and 8 ℃ (7 days) for 20 days. Fresh weight loss rate was under 1% as maximum permissible weight loss in treated OTR films except perforated film as a control during storage. Carbon dioxide concentration within a package for the storage period showed a lower value than the maximum CO2 concentration tolerated range (15 %) in treated OTR films and even the concentration of high OTR film treatment; from 20,000cc to 100,000cc were less than 3%. 1,300 cc had a suitable carbon dioxide range as over 5 % under 15 % at 5 days after storage until finished experiments and CO2 injection treatment was quickly drop the 15 % at storage after 1 day, but it kept around 15 % during storage. Oxygen concentration was maintained between 10 to 15 % in 1,300 cc and CO2 injection treatments, but other treatments were kept in 19 to 21 %. Ethylene concentration was showed very higher concentration at the CO2 injection treatment than OTR treatments. In the OTR treatments, 1,300 cc showed the highest concentration in ethylene and 20,000 cc film had lowest. Firmness was maintained highest in 1,300cc, but there was not shown any significant differences among other OTR treatments. Visual quality had shown the best result in 20,000 cc that showed marketable quality until 20 days after storage. 20,000 cc and perforated film had better than other treatments in off-odor and the 1,300 cc and CO2 injection treatments have occurred strong off-odor even after 10 minutes. As a result of the difference between Hunter ‘L’ and ‘a’ values of chroma meter, the 1,300cc and CO2 injection treatments were delayed color developments and other treatments did not shown any significant differences. The results indicate that effectiveness for maintaining the freshness was best achieved at 20,000 cc•m-2•day•atm. Although 1,300 cc and CO2 injection treatments were in appropriate MA condition, it showed darkening of strawberry calyx and excessive reduction of coloring due to high carbon dioxide concentration during storage. While 1,300cc and CO2 injection treatments were considered as appropriate treatments for exports to Singapore, but the result was shown different. These results are based on cultivar characteristics of strawberry 'Maehyang'.

Keywords: carbon dioxide, firmness, shelf-life, visual quality

Procedia PDF Downloads 396
2524 Life Cycle Carbon Dioxide Emissions from the Construction Phase of Highway Sector in China

Authors: Yuanyuan Liu, Yuanqing Wang, Di Li

Abstract:

Carbon dioxide (CO2) emissions mitigation from road construction activities is one of the potential pathways to deal with climate change due to its higher use of materials, machinery energy consumption, and high quantity of vehicle and equipment fuels for transportation and on-site construction activities. Aiming to assess the environmental impact of the road infrastructure construction activities and to identify hotspots of emissions sources, this study developed a life-cycle CO2 emissions assessment framework covering three stages of material production, to-site and on-site transportation under the guidance of the principle of LCA ISO14040. Then streamlined inventory analysis on sub-processes of each stage was conducted based on the budget files from cases of highway projects in China. The calculation results were normalized into functional unit represented as ton per km per lane. Then a comparison between the amount of emissions from each stage, and sub-process was made to identify the major contributor in the whole highway lifecycle. In addition, the calculating results were used to be compared with results in other countries for understanding the level of CO2 emissions associated with Chinese road infrastructure in the world. The results showed that materials production stage produces the most of the CO2 emissions (for more than 80%), and the production of cement and steel accounts for large quantities of carbon emissions. Life cycle CO2 emissions of fuel and electric energy associated with to-site and on-site transportation vehicle and equipment are a minor component of total life cycle CO2 emissions from highway project construction activities. Bridges and tunnels are dominant large carbon contributor compared to the road segments. The life cycle CO2 emissions of road segment in highway project in China are slightly higher than the estimation results of highways in European countries and USA, about 1500 ton per km per lane. In particularly, the life cycle CO2 emissions of road pavement in majority cities all over the world are about 500 ton per km per lane. However, there is obvious difference between the cities when the estimation on life cycle CO2 emissions of highway projects included bridge and tunnel. The findings of the study could offer decision makers a more comprehensive reference to understand the contribution of road infrastructure to climate change, especially understand the contribution from road infrastructure construction activities in China. In addition, the identified hotspots of emissions sources provide the insights of how to reduce road carbon emissions for development of sustainable transportation.

Keywords: carbon dioxide emissions, construction activities, highway, life cycle assessment

Procedia PDF Downloads 263