Search results for: exsport-import of industrial products
832 Synthesized Doped TiO2 Photocatalysts for Mineralization of Quinalphos from Aqueous Streams
Authors: Nidhi Sharotri, Dhiraj Sud
Abstract:
Water pollution by pesticides constitutes a serious ecological problem due to their potential toxicity and bioaccumulation. The widespread use of pesticides in industry and agriculture along with their resistance to natural decomposition, biodegradation, chemical and photochemical degradation under typical environmental conditions has resulted in the emergence of these chemicals and their transformed products in natural water. Among AOP’s, heterogeneous photocatalysis using TiO2 as photocatalyst appears as the most emerging destructive technology for mineralization of the pollutant in aquatic streams. Among the various semiconductors (TiO2, ZnO, CdS, FeTiO3, MnTiO3, SrTiO2 and SnO2), TiO2 has proven to be the most efficient photocatalyst for environmental applications due to its biological and chemical inertness, high photo reactivity, non-toxicity, and photo stability. Semiconductor photocatalysts are characterized by an electronic band structure in which valence band and conduction band are separated by a band gap, i.e. a region of forbidden energy. Semiconductor based photocatalysts produces e-/h+ pairs which have been employed for degradation of organic pollutants. The present paper focuses on modification of TiO2 photocatalyst in order to shift its absorption edge towards longer wavelength to make it active under natural light. Semiconductor TiO2 photocatalysts was prepared by doping with anion (N), cation (Mn) and double doped (Mn, N) using greener approach. Titanium isopropoxide is used as titania precursor and ethanedithiol, hydroxyl amine hydrochloride, manganous chloride as sulphur, nitrogen and manganese precursors respectively. Synthesized doped TiO2 nanomaterials are characterized for surface morphology (SEM, TEM), crystallinity (XRD) and optical properties (absorption spectra and band gap). EPR data confirms the substitutional incorporation of Mn2+ in TiO2 lattice. The doping influences the phase transformation of rutile and anatase phase crystal and thereby the absorption spectrum changes were observed. The effect of variation of reaction parameters such as solvent, reaction time and calcination temperature on the yield, surface morphology and optical properties was also investigated. The TEM studies show the particle size of nanomaterials varies from 10-50 nm. The calculated band gap of nanomaterials varies from 2.30-2.60 eV. The photocatalytic degradation of organic pollutant organophosphate pesticide (Quinalphos) has been investigated by studying the changes in UV absorption spectrum and the promising results were obtained under visible light. The complete mineralization of quinalphos has occurred as no intermediates were recorded after 8 hrs of degradation confirmed from the HPLC studies.Keywords: quinalphos, doped-TiO2, mineralization, EPR
Procedia PDF Downloads 328831 Environmental Aspects of Alternative Fuel Use for Transport with Special Focus on Compressed Natural Gas (CNG)
Authors: Szymon Kuczynski, Krystian Liszka, Mariusz Laciak, Andrii Oliinyk, Adam Szurlej
Abstract:
The history of gaseous fuel use in the motive power of vehicles dates back to the second half of the nineteenth century, and thus the beginnings of the automotive industry. The engines were powered by coal gas and became the prototype for internal combustion engines built so far. It can thus be considered that this construction gave rise to the automotive industry. As the socio-economic development advances, so does the number of motor vehicles. Although, due to technological progress in recent decades, the emissions generated by internal combustion engines of cars have been reduced, a sharp increase in the number of cars and the rapidly growing traffic are an important source of air pollution and a major cause of acoustic threat, in particular in large urban agglomerations. One of the solutions, in terms of reducing exhaust emissions and improving air quality, is a more extensive use of alternative fuels: CNG, LNG, electricity and hydrogen. In the case of electricity use for transport, it should be noted that the environmental outcome depends on the structure of electricity generation. The paper shows selected regulations affecting the use of alternative fuels for transport (including Directive 2014/94/EU) and its dynamics between 2000 and 2015 in Poland and selected EU countries. The paper also gives a focus on the impact of alternative fuels on the environment by comparing the volume of individual emissions (compared to the emissions from conventional fuels: petrol and diesel oil). Bearing in mind that the extent of various alternative fuel use is determined in first place by economic conditions, the article describes the price relationships between alternative and conventional fuels in Poland and selected EU countries. It is pointed out that although Poland has a wealth of experience in using methane alternative fuels for transport, one of the main barriers to their development in Poland is the extensive use of LPG. In addition, a poorly developed network of CNG stations in Poland, which does not allow easy transport, especially in the northern part of the country, is a serious problem to a further development of CNG use as fuel for transport. An interesting solution to this problem seems to be the use of home CNG filling stations: Home Refuelling Appliance (HRA, refuelling time 8-10 hours) and Home Refuelling Station (HRS, refuelling time 8-10 minutes). The team is working on HRA and HRS technologies. The article also highlights the impact of alternative fuel use on energy security by reducing reliance on imports of crude oil and petroleum products.Keywords: alternative fuels, CNG (Compressed Natural Gas), CNG stations, LNG (Liquefied Natural Gas), NGVs (Natural Gas Vehicles), pollutant emissions
Procedia PDF Downloads 227830 Extracellular Hydrolase-Producing Bacteria Isolated from Chilca Salterns in Peru
Authors: Carol N. Flores-Fernández, Guadalupe Espilco, Cynthia Esquerre, Amparo I. Zavaleta
Abstract:
Saline environments represent a valuable source of enzymes with novel properties and particular features for application in food, pharmaceutical and chemical industry. This study focuses on the isolation and screening of hydrolase-producing bacteria from Chilca salterns and the evaluation of their biotechnological potential. Soil samples were collected from Chilca salterns in Peru. For the isolation, medium containing 0.2 % of yeast extract, 5 % of NaCl and 10 % of the soil sample was used. After 72 h of incubation at 37 °C, serial dilutions were made up to 10−12 dilutions, spread on agar plates with 0.5 % of yeast extract and 5 % of NaCl, and incubated at 37 °C for 48 h. Screening of hydrolase-producing bacteria was carried out for cellulases, amylases, lipases, DNase, and proteases on specific media. Moreover, protease-producing bacteria were tested using protein extracted from the following legumes as substrate: Glycine max, Lupinus mutabilis, Pisum sativum, Erythrina edulis, Cicer arietinum, Phaseolus vulgaris and Vicia faba. A total of 16 strains were isolated from soil samples. On the screening media; 75, 44, 81 and 50 % were cellulase, amylase, DNase and protease producers, respectively. Also, 19 % of the isolates produced all the hydrolytic enzymes above mentioned. Lipase producers were not found. The 37 % and 12 % of the strains grew at 20 % and 30 % of salt concentration, respectively. In addition, 75 % of the strains grew at pH range between 5 and 10. From the total of protease-producing bacteria, 100 % hydrolyzed Glycine max, Lupinus mutabilis, and Pisum sativum protein, while 87 % hydrolyzed Erythrina edulis and Cicer arietinum protein. Finally, 75 % and 50 % of the strains hydrolyzed Phaseolus vulgaris and Vicia faba protein, respectively. Hydrolase-producing bacteria isolated from Chilca salterns in Peru grew at high salt concentrations and wide range of pH. In addition, protease-producing bacteria hydrolyzed protein from different sources such as leguminous. These enzymes have great biotechnological potential and could be used for different industrial processes and applications.Keywords: bacteria, extracellular, hydrolases, Peru, salterns
Procedia PDF Downloads 208829 Gap between Knowledge and Behaviour in Recycling Domestic Solid Waste: Evidence from Manipal, India
Authors: Vidya Pratap, Seena Biju, Keshavdev A.
Abstract:
In the educational town of Manipal (located in southern India) households dispose their wastes without segregation. Mixed wastes (organic, inorganic and hazardous items) are collected either by private collectors or by the local municipal body in trucks and taken to dump yards. These collectors select certain recyclables from the collected trash and sell them to scrap merchants to earn some extra money. Rag pickers play a major role in picking up card board boxes, glass bottles and milk sachets from dump yards and public areas and scrap iron from construction sites for recycling. In keeping with the Indian Prime Minister’s mission of Swachh Bharat (A Clean India), the local municipal administration is taking efforts to ensure segregation of domestic waste at source. With this in mind, each household in a residential area in Manipal was given two buckets – for wet and dry wastes (wet waste referred to organic waste while dry waste included recyclable and hazardous items). A study was conducted in this locality covering a cluster of 145 households to assess the residents’ knowledge of recyclable, organic and hazardous items commonly disposed by households. Another objective of this research was to evaluate the extent to which the residents actually dispose their wastes appropriately. Questionnaires were self-administered to a member of each household with the assistance of individuals speaking the local language whenever needed. Respondents’ knowledge of whether an item was organic, inorganic or hazardous was captured through a questionnaire containing a list of 50 common items. Their behaviour was captured by asking how they disposed these items. Results show that more than 70% of respondents are aware that banana and orange peels, potato skin, egg shells and dried leaves are organic; similarly, more than 70% of them consider newspapers, notebook and printed paper are recyclable. Less than 65% of respondents are aware that plastic bags and covers and plastic bottles are recyclable. However, the results of the respondents’ recycling behaviour is less impressive. Fewer than 35% of respondents recycle card board boxes, milk sachets and glass bottles. Unfortunately, since plastic items like plastic bags and covers and plastic bottles are not accepted by scrap merchants, they are not recycled. This study shows that the local municipal authorities must find ways to recycle plastic into products, alternate fuel etc.Keywords: behaviour, knowledge, plastic waste management, recyclables
Procedia PDF Downloads 172828 Biostimulant Activity of Chitooligomers: Effect of Different Degrees of Acetylation and Polymerization on Wheat Seedlings under Salt Stress
Authors: Xiaoqian Zhang, Ping Zou, Pengcheng Li
Abstract:
Salt stress is one of the most serious abiotic stresses, and it can lead to the reduction of agricultural productivity. High salt concentration makes it more difficult for roots to absorb water and disturbs the homeostasis of cellular ions resulting in osmotic stress, ion toxicity and generation of reactive oxygen species (ROS). Compared with the normal physiological conditions, salt stress could inhibit the photosynthesis, break metabolic balance and damage cellular structures, and ultimately results in the reduction of crop yield. Therefore it is vital to develop practical methods for improving the salt tolerance of plants. Chitooligomers (COS) is partially depolymerized products of chitosan, which is consisted of D-glucosamine and N-acetyl-D-glucosamine. In agriculture, COS has the ability to promote plant growth and induce plant innate immunity. The bioactivity of COS closely related to its degree of polymerization (DP) and acetylation (DA). However, most of the previous reports fail to mention the function of COS with different DP and DAs in improving the capacity of plants against salt stress. Accordingly, in this study, chitooligomers (COS) with different degrees of DAs were used to test wheat seedlings response to salt stress. In addition, the determined degrees of polymerization (DPs) COS(DP 4-12) and a heterogeneous COS mixture were applied to explore the relationship between the DP of COSs and its effect on the growth of wheat seedlings in response to salt stress. It showed that COSs, the exogenous elicitor, could promote the growth of wheat seedling, reduce the malondialdehyde (MDA) concentration, and increase the activities of antioxidant enzymes. The results of mRNA expression level test for salt stress-responsive genes indicated that COS keep plants away from being hurt by the salt stress via the regulation of the concentration and the increased antioxidant enzymes activities. Moreover, it was found that the activities of COS was closely related to its Das and COS (DA: 50%) displayed the best salt resistance activity to wheat seedlings. The results also showed that COS with different DP could promote the growth of wheat seedlings under salt stress. COS with a DP (6-8) showed better activities than the other tested samples, implied its activity had a close relationship with its DP. After treatment with chitohexaose, chitoheptaose, and chitooctaose, the photosynthetic parameters were improved obviously. The soluble sugar and proline contents were improved by 26.7%-53.3% and 43.6.0%-70.2%, respectively, while the concentration of malondialdehyde (MDA) was reduced by 36.8% - 49.6%. In addition, the antioxidant enzymes activities were clearly activated. At the molecular level, the results revealed that they could obviously induce the expression of Na+/H+ antiporter genes. In general, these results were fundamental to the study of action mechanism of COS on promoting plant growth under salt stress and the preparation of plant growth regulator.Keywords: chitooligomers (COS), degree of polymerization (DP), degree of acetylation (DA), salt stress
Procedia PDF Downloads 175827 Increased Energy Efficiency and Improved Product Quality in Processing of Lithium Bearing Ores by Applying Fluidized-Bed Calcination Systems
Authors: Edgar Gasafi, Robert Pardemann, Linus Perander
Abstract:
For the production of lithium carbonate or hydroxide out of lithium bearing ores, a thermal activation (calcination/decrepitation) is required for the phase transition in the mineral to enable an acid respectively soda leaching in the downstream hydrometallurgical section. In this paper, traditional processing in Lithium industry is reviewed, and opportunities to reduce energy consumption and improve product quality and recovery rate will be discussed. The conventional process approach is still based on rotary kiln calcination, a technology in use since the early days of lithium ore processing, albeit not significantly further developed since. A new technology, at least for the Lithium industry, is fluidized bed calcination. Decrepitation of lithium ore was investigated at Outotec’s Frankfurt Research Centre. Focusing on fluidized bed technology, a study of major process parameters (temperature and residence time) was performed at laboratory and larger bench scale aiming for optimal product quality for subsequent processing. The technical feasibility was confirmed for optimal process conditions on pilot scale (400 kg/h feed input) providing the basis for industrial process design. Based on experimental results, a comprehensive Aspen Plus flow sheet simulation was developed to quantify mass and energy flow for the rotary kiln and fluidized bed system. Results show a significant reduction in energy consumption and improved process performance in terms of temperature profile, product quality and plant footprint. The major conclusion is that a substantial reduction of energy consumption can be achieved in processing Lithium bearing ores by using fluidized bed based systems. At the same time and different from rotary kiln process, an accurate temperature and residence time control is ensured in fluidized-bed systems leading to a homogenous temperature profile in the reactor which prevents overheating and sintering of the solids and results in uniform product quality.Keywords: calcination, decrepitation, fluidized bed, lithium, spodumene
Procedia PDF Downloads 230826 Orange Leaves and Rice Straw on Methane Emission and Milk Production in Murciano-Granadina Dairy Goat Diet
Authors: Tamara Romero, Manuel Romero-Huelva, Jose V. Segarra, Jose Castro, Carlos Fernandez
Abstract:
Many foods resulting from processing and manufacturing end up as waste, most of which is burned, dumped into landfills or used as compost, which leads to wasted resources, and environmental problems due to unsuitable disposal. Using residues of the crop and food processing industries to feed livestock has the advantage to obviating the need for costly waste management programs. The main residue generated in citrus cultivations and rice crop are pruning waste and rice straw, respectively. Within Spain, the Valencian Community is one of the world's oldest citrus and rice production areas. The objective of this experiment found out the effects of including orange leaves and rice straw as ingredients in the concentrate diets of goats, on milk production and methane (CH₄) emissions. Ten Murciano-Granadina dairy goats (45 kg of body weight, on average) in mid-lactation were selected in a crossover design experiment, where each goat received two treatments in 2 periods. Both groups were fed with 1.7 kg pelleted mixed ration; one group (n= 5) was a control (C) and the other group (n= 5) used orange leaves and rice straw (OR). The forage was alfalfa hay, and it was the same for the two groups (1 kg of alfalfa was offered by goat and day). The diets employed to achieve the requirements during lactation period for caprine livestock. The goats were allocated to individual metabolism cages. After 14 days of adaptation, feed intake and milk yield were recorded daily over a 5 days period. Physico-chemical parameters and somatic cell count in milk samples were determined. Then, gas exchange measurements were recorded individually by an open-circuit indirect calorimetry system using a head box. The data were analyzed by mixed model with diet and digestibility as fixed effect and goat as random effect. No differences were found for dry matter intake (2.23 kg/d, on average). Higher milk yield was found for C diet than OR (2.3 vs. 2.1 kg/goat and day, respectively) and, greater milk fat content was observed for OR than C (6.5 vs. 5.5%, respectively). The cheese extract was also greater in OR than C (10.7 vs. 9.6%). Goats fed OR diet produced significantly fewer CH₄ emissions than C diet (27 vs. 30 g/d, respectively). These preliminary results (LIFE Project LOWCARBON FEED LIFE/CCM/ES/000088) suggested that the use of these waste by-products was effective in reducing CH₄ emission without detrimental effect on milk yield.Keywords: agricultural waste, goat, milk production, methane emission
Procedia PDF Downloads 148825 Airborne Particulate Matter Passive Samplers for Indoor and Outdoor Exposure Monitoring: Development and Evaluation
Authors: Kholoud Abdulaziz, Kholoud Al-Najdi, Abdullah Kadri, Konstantinos E. Kakosimos
Abstract:
The Middle East area is highly affected by air pollution induced by anthropogenic and natural phenomena. There is evidence that air pollution, especially particulates, greatly affects the population health. Many studies have raised a warning of the high concentration of particulates and their affect not just around industrial and construction areas but also in the immediate working and living environment. One of the methods to study air quality is continuous and periodic monitoring using active or passive samplers. Active monitoring and sampling are the default procedures per the European and US standards. However, in many cases they have been inefficient to accurately capture the spatial variability of air pollution due to the small number of installations; which eventually is attributed to the high cost of the equipment and the limited availability of users with expertise and scientific background. Another alternative has been found to account for the limitations of the active methods that is the passive sampling. It is inexpensive, requires no continuous power supply, and easy to assemble which makes it a more flexible option, though less accurate. This study aims to investigate and evaluate the use of passive sampling for particulate matter pollution monitoring in dry tropical climates, like in the Middle East. More specifically, a number of field measurements have be conducted, both indoors and outdoors, at Qatar and the results have been compared with active sampling equipment and the reference methods. The samples have been analyzed, that is to obtain particle size distribution, by applying existing laboratory techniques (optical microscopy) and by exploring new approaches like the white light interferometry to. Then the new parameters of the well-established model have been calculated in order to estimate the atmospheric concentration of particulates. Additionally, an extended literature review will investigate for new and better models. The outcome of this project is expected to have an impact on the public, as well, as it will raise awareness among people about the quality of life and about the importance of implementing research culture in the community.Keywords: air pollution, passive samplers, interferometry, indoor, outdoor
Procedia PDF Downloads 398824 Experimental and Theoretical Mass Transfer Studies of Pure Carbondioxide Absorption in Sodium Hydroxide in Millichannels
Authors: A. Durgadevi, S. Pushpavanam
Abstract:
For the past several decades, CO2 levels have been dramatically increasing in the atmosphere due to the man-made emissions such as fossil fuel-fired power plants. With the increase in CO2 emissions, CO2 concentration in the atmosphere has increased resulting in global warming. This shows the need to study different ways to capture the emitted CO2 directly from the exhausts of power plants or atmosphere. There are several ways to remove CO2, such as absorption into a liquid solvent, adsorption into a solid, cryogenic separation, permeation through membranes and photochemical conversion. In most industries, the absorption of CO2 in chemical solvents (in absorption towers) is used for CO2 capture. In these towers, the mass transfer along with chemical reactions take place between the gas and liquid phase. This helps in the separation of CO2 from other gases. It is important to understand these processes in detail. These flow patterns are difficult to maintain in large scale industrial absorbers. So to get accurate information controlled gas-liquid absorption experiments are carried out in milli-channels in this work under controlled atmosphere. The absorption experiments of CO2 in varying concentrations of sodium hydroxide solution are carried out in T-junction glass milli-channels with a circular cross section (inner diameter of 2mm). The gas and liquid flow rates are controlled by a mass flow controller (MFC) and a Harvard syringe pump respectively. The slug flow in the channel is recorded using a camera and the videos are analysed. The gas slug of pure CO2 is found to decrease in size along the length of the channel due to absorption of gas in the liquid. This is also captured with the model developed and the mass transfer characteristics are studied. The pressure drop across the channel is determined by sum of the pressure drops from the gas slugs and the liquid plugs. A dimensionless correlation for the mass transfer coefficient is developed in terms of Sherwood number and compared with the existing correlations in the literature. They are found to be in close agreement with each other. In this case, due to the presence of chemical reaction, the enhancement of mass transfer is obtained. This is quantified with the help of an enhancement factor.Keywords: absorption, enhancement factor, mass transfer coefficient, Sherwood number
Procedia PDF Downloads 176823 Factors Affecting Profitability of Pharmaceutical Company During the COVID-19 Pandemic: An Indonesian Evidence
Authors: Septiany Trisnaningtyas
Abstract:
Purpose: This research aims to examine the factors affecting the profitability of pharmaceutical company during the Covid-19 Pandemic in Indonesia. A sharp decline in the number of patients coming to the hospital for treatment during the pandemic has an impact on the growth of the pharmaceutical sector and brought major changes in financial position and business performance. Pharmaceutical companies that provide products related to the Covid-19 pandemic can survive and continue to grow. This study investigates the factors affecting the profitability of pharmaceutical company during the Covid-19 Pandemic in Indonesia associated with the number of Covid-19 cases. Design/methodology/approach: This study uses panel-data regression models to evaluate the influence of the number of Covid-19 confirmed cases on profitability of ninelisted pharmaceuticalcompanies in Indonesia. This research is based on four independent variables that were empirically examined for their relationship with profitability. These variables are liquidity (current ratio), growth rate (sales growth), firm size (total sales), and market power (the Lerner index). Covid-19 case is used as moderating variable. Data of nine pharmaceutical companies listed on the Indonesia Stock Exchange covering the period of 2018–2021 were extracted from companies’ quarterly annual reports. Findings: In the period during Covid-19, company growth (sales growth) and market power (lerner index) have a positive and significant relationship to ROA and ROE. Total of confirmed Covid-19 cases has a positive and significant relationship to ROA and is proven to have a moderating effect between company’s growth (sales growth) to ROA and ROE and market power (Lerner index) to ROA. Research limitations/implications: Due to data availability, this study only includes data from nine listed pharmaceutical companies in Indonesian Stock exchange and quarterly annual reportscovering the period of 2018-2021. Originality/value: This study focuses onpharmaceutical companies in Indonesia during Covid-19 pandemic. Previous study analyzes the data from pharmaceutical companies’ annual reports since 2014 and focus on universal health coverage (national health insurance) implementation from the Indonesian government. This study analyzes the data using fixed effect panel-data regression models to evaluate the influence of Covid-19 confirmed cases on profitability. Pooled ordinary least squares regression and fixed effects were used to analyze the data in previous study. This study also investigate the moderating effect of Covid-19 confirmed cases to profitability in relevant with the pandemic situation.Keywords: profitability, indonesia, pharmaceutical, Covid-19
Procedia PDF Downloads 123822 Comparing Productivity of the Foreign versus Local Construction Workers Based on Their Level of Technical Training and Cultural Characteristics: Case Study of Kish Island, Iran
Authors: Mansour Rezvani, Mohammad Mahdi Mortaheb
Abstract:
This study considers the employment of foreign workforce in Kish Free Trade and Industrial Zone and aims to investigate the productivity of foreign construction labours as compared to their local counterpart. Moreover, this study compares work skills and experience of foreign and local Iranian construction workers to optimize construction working conditions. The results and findings have been effectively applied to develop a training program to optimize and promote Iranian workforce productivity and effectiveness in construction industry in comparison with foreign workforce. It is hoped that the accumulated findings contribute to decrease demand for foreign workers and skills shortages in construction sectors. Therefore, job vacancies for local residents in Kish and other looking for job people in main lands will be increased. The method of collecting data has been conducted by distributing a questionnaire and interviewing most foreign construction workers, local Iranian construction works and the project managers of five mega projects in Kish Island including Mica mall, Basak, Persian, Damoon and Sarina mall. All data have been analyzed by SPSS and Excel software. A topic-related survey was conducted through a structured questionnaire including 54 employers, 20 contractors and 13 consultants. About 56 factors were identified. After implementing the context validity test, 52 factors were stated in 52 questions based on five major groups consist of: (1) economical, (2) social and cultural, (3) individual, (4) technical, (5) organizational, environmental and legal. Based on the quantified Relative Importance Index, the ten most important factors, ten less important factors, and three most important categories were identified. To date, there is not any comprehensive study that explores the important critical factors in mega construction projects on Kish Island to identify the major problems to decrease demand for foreign workers.Keywords: cultural characteristics, foreign worker, local construction workers, productivity, technical training
Procedia PDF Downloads 146821 Usage of Crude Glycerol for Biological Hydrogen Production, Experiments and Analysis
Authors: Ilze Dimanta, Zane Rutkovska, Vizma Nikolajeva, Janis Kleperis, Indrikis Muiznieks
Abstract:
Majority of word’s steadily increasing energy consumption is provided by non-renewable fossil resources. Need to find an alternative energy resource is essential for further socio-economic development. Hydrogen is renewable, clean energy carrier with high energy density (142 MJ/kg, accordingly – oil has 42 MJ/kg). Biological hydrogen production is an alternative way to produce hydrogen from renewable resources, e.g. using organic waste material resource fermentation that facilitate recycling of sewage and are environmentally benign. Hydrogen gas is produced during the fermentation process of bacteria in anaerobic conditions. Bacteria are producing hydrogen in the liquid phase and when thermodynamic equilibrium is reached, hydrogen is diffusing from liquid to gaseous phase. Because of large quantities of available crude glycerol and the highly reduced nature of carbon in glycerol per se, microbial conversion of it seems to be economically and environmentally viable possibility. Such industrial organic waste product as crude glycerol is perspective for usage in feedstock for hydrogen producing bacteria. The process of biodiesel production results in 41% (w/w) of crude glycerol. The developed lab-scale test system (experimental bioreactor) with hydrogen micro-electrode (Unisense, Denmark) was used to determine hydrogen production yield and rate in the liquid phase. For hydrogen analysis in the gas phase the RGAPro-100 mass-spectrometer connected to the experimental test-system was used. Fermentative bacteria strains were tested for hydrogen gas production rates. The presence of hydrogen in gaseous phase was measured using mass spectrometer but registered concentrations were comparatively small. To decrease the hydrogen partial pressure in liquid phase reactor with a system for continuous bubbling with inert gas was developed. H2 production rate for the best producer in liquid phase reached 0,40 mmol H2/l, in gaseous phase - 1,32 mmol H2/l. Hydrogen production rate is time dependent – higher rate of hydrogen production is at the fermentation process beginning when concentration increases, but after three hours of fermentation, it decreases.Keywords: bio-hydrogen, fermentation, experimental bioreactor, crude glycerol
Procedia PDF Downloads 522820 Recycling of Sintered NdFeB Magnet Waste Via Oxidative Roasting and Selective Leaching
Authors: W. Kritsarikan, T. Patcharawit, T. Yingnakorn, S. Khumkoa
Abstract:
Neodymium-iron-boron (NdFeB) magnets classified as high-power magnets are widely used in various applications such as electrical and medical devices and account for 13.5 % of the permanent magnet’s market. Since its typical composition of 29 - 32 % Nd, 64.2 – 68.5 % Fe and 1 – 1.2 % B contains a significant amount of rare earth metals and will be subjected to shortages in the future. Domestic NdFeB magnet waste recycling should therefore be developed in order to reduce social, environmental impacts toward a circular economy. Most research works focus on recycling the magnet wastes, both from the manufacturing process and end of life. Each type of wastes has different characteristics and compositions. As a result, these directly affect recycling efficiency as well as the types and purity of the recyclable products. This research, therefore, focused on the recycling of manufacturing NdFeB magnet waste obtained from the sintering stage of magnet production and the waste contained 23.6% Nd, 60.3% Fe and 0.261% B in order to recover high purity neodymium oxide (Nd₂O₃) using hybrid metallurgical process via oxidative roasting and selective leaching techniques. The sintered NdFeB waste was first ground to under 70 mesh prior to oxidative roasting at 550 - 800 °C to enable selective leaching of neodymium in the subsequent leaching step using H₂SO₄ at 2.5 M over 24 h. The leachate was then subjected to drying and roasting at 700 – 800 °C prior to precipitation by oxalic acid and calcination to obtain neodymium oxide as the recycling product. According to XRD analyses, it was found that increasing oxidative roasting temperature led to an increasing amount of hematite (Fe₂O₃) as the main composition with a smaller amount of magnetite (Fe₃O₄) found. Peaks of neodymium oxide (Nd₂O₃) were also observed in a lesser amount. Furthermore, neodymium iron oxide (NdFeO₃) was present and its XRD peaks were pronounced at higher oxidative roasting temperatures. When proceeded to acid leaching and drying, iron sulfate and neodymium sulfate were mainly obtained. After the roasting step prior to water leaching, iron sulfate was converted to form hematite as the main compound, while neodymium sulfate remained in the ingredient. However, a small amount of magnetite was still detected by XRD. The higher roasting temperature at 800 °C resulted in a greater Fe₂O₃ to Nd₂(SO₄)₃ ratio, indicating a more effective roasting temperature. Iron oxides were subsequently water leached and filtered out while the solution contained mainly neodymium sulfate. Therefore, low oxidative roasting temperature not exceeding 600 °C followed by acid leaching and roasting at 800 °C gave the optimum condition for further steps of precipitation and calcination to finally achieve neodymium oxide.Keywords: NdFeB magnet waste, oxidative roasting, recycling, selective leaching
Procedia PDF Downloads 182819 UV-Enhanced Room-Temperature Gas-Sensing Properties of ZnO-SnO2 Nanocomposites Obtained by Hydrothermal Treatment
Authors: Luís F. da Silva, Ariadne C. Catto, Osmando F. Lopes, Khalifa Aguir, Valmor R. Mastelaro, Caue Ribeiro, Elson Longo
Abstract:
Gas detection is important for controlling industrial, and vehicle emissions, agricultural residues, and environmental control. In last decades, several semiconducting oxides have been used to detect dangerous or toxic gases. The excellent gas-sensing performance of these devices have been observed at high temperatures (~250 °C), which forbids the use for the detection of flammable and explosive gases. In this way, ultraviolet light activated gas sensors have been a simple and promising alternative to achieve room temperature sensitivity. Among the semiconductor oxides which exhibit a good performance as gas sensor, the zinc oxide (ZnO) and tin oxide (SnO2) have been highlighted. Nevertheless, their poor selectivity is the main disadvantage for application as gas sensor devices. Recently, heterostructures combining these two semiconductors (ZnO-SnO2) have been studied as an alternative way to enhance the gas sensor performance (sensitivity, selectivity, and stability). In this work, we investigated the influence of mass ratio Zn:Sn on the properties of ZnO-SnO2 nanocomposites prepared by hydrothermal treatment for 4 hours at 200 °C. The crystalline phase, surface, and morphological features were characterized by X-ray diffraction (XRD), high-resolution transmission electron (HR-TEM), and X-ray photoelectron spectroscopy (XPS) measurements. The gas sensor measurements were carried out at room-temperature under ultraviolet (UV) light irradiation using different ozone levels (0.06 to 0.61 ppm). The XRD measurements indicate the presence of ZnO and SnO2 crystalline phases, without the evidence of solid solution formation. HR-TEM analysis revealed that a good contact between the SnO2 nanoparticles and the ZnO nanorods, which are very important since interface characteristics between nanostructures are considered as challenge to development new and efficient heterostructures. Electrical measurements proved that the best ozone gas-sensing performance is obtained for ZnO:SnO2 (50:50) nanocomposite under UV light irradiation. Its sensitivity was around 6 times higher when compared to SnO2 pure, a traditional ozone gas sensor. These results demonstrate the potential of ZnO-SnO2 heterojunctions for the detection of ozone gas at room-temperature when irradiated with UV light irradiation.Keywords: hydrothermal, zno-sno2, ozone sensor, uv-activation, room-temperature
Procedia PDF Downloads 284818 Sustainable Hydrogel Nanocomposites Based on Grafted Chitosan and Clay for Effective Adsorption of Cationic Dye
Authors: H. Ferfera-Harrar, T. Benhalima, D. Lerari
Abstract:
Contamination of water, due to the discharge of untreated industrial wastewaters into the ecosystem, has become a serious problem for many countries. In this study, bioadsorbents based on chitosan-g-poly(acrylamide) and montmorillonite (MMt) clay (CTS-g-PAAm/MMt) hydrogel nanocomposites were prepared via free‐radical grafting copolymerization and crosslinking of acrylamide monomer (AAm) onto natural polysaccharide chitosan (CTS) as backbone, in presence of various contents of MMt clay as nanofiller. Then, they were hydrolyzed to obtain highly functionalized pH‐sensitive nanomaterials with uppermost swelling properties. Their structure characterization was conducted by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses. The adsorption performances of the developed nanohybrids were examined for removal of methylene blue (MB) cationic dye from aqueous solutions. The factors affecting the removal of MB, such as clay content, pH medium, adsorbent dose, initial dye concentration and temperature were explored. The adsorption process was found to be highly pH dependent. From adsorption kinetic results, the prepared adsorbents showed remarkable adsorption capacity and fast adsorption rate, mainly more than 88% of MB removal efficiency was reached after 50 min in 200 mg L-1 of dye solution. In addition, the incorporating of various content of clay has enhanced adsorption capacity of CTS-g-PAAm matrix from 1685 to a highest value of 1749 mg g-1 for the optimized nanocomposite containing 2 wt.% of MMt. The experimental kinetic data were well described by the pseudo-second-order model, while the equilibrium data were represented perfectly by Langmuir isotherm model. The maximum Langmuir equilibrium adsorption capacity (qm) was found to increase from 2173 mg g−1 until 2221 mg g−1 by adding 2 wt.% of clay nanofiller. Thermodynamic parameters revealed the spontaneous and endothermic nature of the process. In addition, the reusability study revealed that these bioadsorbents could be well regenerated with desorption efficiency overhead 87% and without any obvious decrease of removal efficiency as compared to starting ones even after four consecutive adsorption/desorption cycles, which exceeded 64%. These results suggest that the optimized nanocomposites are promising as low cost bioadsorbents.Keywords: chitosan, clay, dye adsorption, hydrogels nanocomposites
Procedia PDF Downloads 122817 Assessment of Time-variant Work Stress for Human Error Prevention
Authors: Hyeon-Kyo Lim, Tong-Il Jang, Yong-Hee Lee
Abstract:
For an operator in a nuclear power plant, human error is one of the most dreaded factors that may result in unexpected accidents. The possibility of human errors may be low, but the risk of them would be unimaginably enormous. Thus, for accident prevention, it is quite indispensable to analyze the influence of any factors which may raise the possibility of human errors. During the past decades, not a few research results showed that performance of human operators may vary over time due to lots of factors. Among them, stress is known to be an indirect factor that may cause human errors and result in mental illness. Until now, not a few assessment tools have been developed to assess stress level of human workers. However, it still is questionable to utilize them for human performance anticipation which is related with human error possibility, because they were mainly developed from the viewpoint of mental health rather than industrial safety. Stress level of a person may go up or down with work time. In that sense, if they would be applicable in the safety aspect, they should be able to assess the variation resulted from work time at least. Therefore, this study aimed to compare their applicability for safety purpose. More than 10 kinds of work stress tools were analyzed with reference to assessment items, assessment and analysis methods, and follow-up measures which are known to close related factors with work stress. The results showed that most tools mainly focused their weights on some common organizational factors such as demands, supports, and relationships, in sequence. Their weights were broadly similar. However, they failed to recommend practical solutions. Instead, they merely advised to set up overall counterplans in PDCA cycle or risk management activities which would be far from practical human error prevention. Thus, it was concluded that application of stress assessment tools mainly developed for mental health seemed to be impractical for safety purpose with respect to human performance anticipation, and that development of a new assessment tools would be inevitable if anyone wants to assess stress level in the aspect of human performance variation and accident prevention. As a consequence, as practical counterplans, this study proposed a new scheme for assessment of work stress level of a human operator that may vary over work time which is closely related with the possibility of human errors.Keywords: human error, human performance, work stress, assessment tool, time-variant, accident prevention
Procedia PDF Downloads 671816 Optimized Parameters for Simultaneous Detection of Cd²⁺, Pb²⁺ and CO²⁺ Ions in Water Using Square Wave Voltammetry on the Unmodified Glassy Carbon Electrode
Authors: K. Sruthi, Sai Snehitha Yadavalli, Swathi Gosh Acharyya
Abstract:
Water is the most crucial element for sustaining life on earth. Increasing water pollution directly or indirectly leads to harmful effects on human life. Most of the heavy metal ions are harmful in their cationic form. These heavy metal ions are released by various activities like disposing of batteries, industrial wastes, automobile emissions, and soil contamination. Ions like (Pb, Co, Cd) are carcinogenic and show many harmful effects when consumed more than certain limits proposed by WHO. The simultaneous detection of the heavy metal ions (Pb, Co, Cd), which are highly toxic, is reported in this study. There are many analytical methods for quantifying, but electrochemical techniques are given high priority because of their sensitivity and ability to detect and recognize lower concentrations. Square wave voltammetry was preferred in electrochemical methods due to the absence of background currents which is interference. Square wave voltammetry was performed on GCE for the quantitative detection of ions. Three electrode system consisting of a glassy carbon electrode as the working electrode (3 mm diameter), Ag/Agcl electrode as the reference electrode, and a platinum wire as the counter electrode was chosen for experimentation. The mechanism of detection was done by optimizing the experimental parameters, namely pH, scan rate, and temperature. Under the optimized conditions, square wave voltammetry was performed for simultaneous detection. Scan rates were varied from 5 mV/s to 100 mV/s and found that at 25 mV/s all the three ions were detected simultaneously with proper peaks at particular stripping potential. The variation of pH from 3 to 8 was done where the optimized pH was taken as pH 5 which holds good for three ions. There was a decreasing trend at starting because of hydrogen gas evolution, and after pH 5 again there was a decreasing trend that is because of hydroxide formation on the surface of the working electrode (GCE). The temperature variation from 25˚C to 45˚C was done where the optimum temperature concerning three ions was taken as 35˚C. Deposition and stripping potentials were given as +1.5 V and -1.5 V, and the resting time of 150 seconds was given. Three ions were detected at stripping potentials of Cd²⁺ at -0.84 V, Pb²⁺ at -0.54 V, and Co²⁺ at -0.44 V. The parameters of detection were optimized on a glassy carbon electrode for simultaneous detection of the ions at lower concentrations by square wave voltammetry.Keywords: cadmium, cobalt, lead, glassy carbon electrode, square wave anodic stripping voltammetry
Procedia PDF Downloads 117815 Cross-Sectional Analysis of the Health Product E-Commerce Market in Singapore
Authors: Andrew Green, Jiaming Liu, Kellathur Srinivasan, Raymond Chua
Abstract:
Introduction: The size of Singapore’s online health product (HP) market (e-commerce) is largely unknown. However, it is recognized that a large majority comes from overseas and thus, unregulated. As buying HP from unauthorized sources significantly compromises public health safety, understanding e-commerce users’ demographics and their perceptions on online HP purchasing becomes a pivotal first step to form a basis for recommendations in Singapore’s pharmacovigilance efforts. Objective: To assess the prevalence of online HP purchasing behaviour among Singaporean e-commerce users. Methodology: This is a cross-sectional study targeting Singaporean e-commerce users recruited from various local websites and online forums. Participants were not randomized into study arms but instead stratified by random sampling method based on participants’ age. A self-administered anonymous questionnaire was used to explore participants' demographics, online HP purchasing behaviour, knowledge and attitude. The association of different variables with online HP purchasing behaviour was analysed using logistic regression statistics. Main outcome measures: Prevalence of HP e-commerce users in Singapore (%) and variables that contribute to the prevalence (adjusted prevalent ratio). Results: The study recruited 372 complete and valid responses. The prevalence of online HP consumers among e-commerce users in Singapore is estimated to be 55.9% (1.7 million consumers). Online purchasing of complementary HP (46.9%) was the most prevalent, followed by medical devices (21.6%) and Western medicine (20.5%). Multivariate analysis showed that age is an independent variable that correlates with the likelihood of buying HP online. The prevalence of HP e-commerce users is highest in the 35-44 age group (64.1%) and lowest among the 16-24 age group (36.4%). The most bought HP through the internet are vitamins and minerals (21.5%), non-herbal (15.9%), herbal (13.9%), weight loss (8.7%) and sports (8.4%) supplements. While the top 3 products are distributed equally between the genders, there is a skew towards female respondents (12.4% in females vs. 4.9% in males) for weight loss supplements and towards males (13.2% in males vs. 3.7% in females) for sports supplements. Even though online consumers are in the younger age brackets, our study found that up to 72.0% of HP bought online are bought for others (buyer’s family and/or friends). Multivariate analysis showed a statistically significant association between purchasing HP through online means and the perceptions that 'internet is safe' (adjusted Prevalence Ratio=1.15, CI 1.03-1.28), 'buying HP online is time saving' (PR=1.17, CI 1.01-1.36), and 'recognition of HP brand' (PR=1.21 CI 1.06-1.40). Conclusions: This study has provided prevalence data for online HP market in Singapore, and has allowed the country’s regulatory body to formulate a targeted pharmacovigilance approach to this growing problem.Keywords: e-commerce, pharmaceuticals, pharmacovigilance, Singapore
Procedia PDF Downloads 363814 Assessment of Water Quality of Euphrates River at Babylon Governorate, for Drinking, Irrigation and general, Using Water Quality Index (Canadian Version) (CCMEWQI)
Authors: Amer Obaid Saud
Abstract:
Water quality index (WQI) is considered as an effective tool in categorization of water resources for its quality and suitability for different uses. The Canadian version of water quality index (CCME WQI) which based on the comparison of the water quality parameters to regulatory standards and give a single value to the water quality of a source was applied in this study to assess the water quality of Euphrates river in Iraq at Babylon Governorate north of Baghdad and determine its suitability for aquatic environment (GWQI), drinking water (PWSI) and irrigation(IWQI). Five stations were selected on the river in Babylon (Euphrates River/AL-Musiab, Hindia barrage, two stations at Hilla city and the fifth station at Al-Hshmeya north of Hilla. Fifteen water samples were collected every month during August 2013 to July 2014 at the study sites and analyzed for the physico-chemical parameters like (Temperature, pH, Electrical Conductivity, Total Dissolved Solids(TDS), Total Suspended Solids(TSS), Total Alkalinity, Total Hardness, Calcium and Magnesium Concentration, some of nutrient like Nitrite, Nitrate, Phosphate also the study of concentration of some heavy metals (Fe, Pb, Zn, Cu, Mn, and Cd) in water and comparison of measures to benchmarks such as guidelines and objectives to assess change in water quality. The result of Canadian version of(CCME .WQI) to assess the irrigation water quality (IWQI) of Euphrates river was (83-good) at site one during second seasonal period while the lowest was (66-Fair) in the second station during the fourth seasonal period, the values of potable water supply index (PWSI)that the highest value was (68-Fair) in the fifth site during the second period while the lowest value (42 -Poor) in the second site during the first seasonal period,the highest value for general water quality (GWQI) was (74-Fair) in site five during the second seasonal period, the lowest value (48-Marginal) in the second site during the first seasonal period. It was observed that the main cause of deterioration in water quality was due to the lack of, unprotected river sites ,high anthropogenic activities and direct discharge of industrial effluent.Keywords: Babylon governorate, Canadian version, water quality, Euphrates river
Procedia PDF Downloads 398813 Recycling of Sintered Neodymium-Iron-Boron (NdFeB) Magnet Waste via Oxidative Roasting and Selective Leaching
Authors: Woranittha Kritsarikan
Abstract:
Neodymium-iron-boron (NdFeB) magnets classified as high-power magnets are widely used in various applications such as electrical and medical devices and account for 13.5 % of the permanent magnet’s market. Since its typical composition of 29 - 32 % Nd, 64.2 – 68.5 % Fe and 1 – 1.2 % B contains a significant amount of rare earth metals and will be subjected to shortages in the future. Domestic NdFeB magnet waste recycling should therefore be developed in order to reduce social, environmental impacts toward the circular economy. Most research works focus on recycling the magnet wastes, both from the manufacturing process and end of life. Each type of wastes has different characteristics and compositions. As a result, these directly affect recycling efficiency as well as the types and purity of the recyclable products. This research, therefore, focused on the recycling of manufacturing NdFeB magnet waste obtained from the sintering stage of magnet production and the waste contained 23.6% Nd, 60.3% Fe and 0.261% B in order to recover high purity neodymium oxide (Nd₂O₃) using hybrid metallurgical process via oxidative roasting and selective leaching techniques. The sintered NdFeB waste was first ground to under 70 mesh prior to oxidative roasting at 550 - 800 ᵒC to enable selective leaching of neodymium in the subsequent leaching step using H₂SO₄ at 2.5 M over 24 hours. The leachate was then subjected to drying and roasting at 700 – 800 ᵒC prior to precipitation by oxalic acid and calcination to obtain neodymium oxide as the recycling product. According to XRD analyses, it was found that increasing oxidative roasting temperature led to the increasing amount of hematite (Fe₂O₃) as the main composition with a smaller amount of magnetite (Fe3O4) found. Peaks of neodymium oxide (Nd₂O₃) were also observed in a lesser amount. Furthermore, neodymium iron oxide (NdFeO₃) was present and its XRD peaks were pronounced at higher oxidative roasting temperature. When proceeded to acid leaching and drying, iron sulfate and neodymium sulfate were mainly obtained. After the roasting step prior to water leaching, iron sulfate was converted to form hematite as the main compound, while neodymium sulfate remained in the ingredient. However, a small amount of magnetite was still detected by XRD. The higher roasting temperature at 800 ᵒC resulted in a greater Fe2O3 to Nd2(SO4)3 ratio, indicating a more effective roasting temperature. Iron oxides were subsequently water leached and filtered out while the solution contained mainly neodymium sulfate. Therefore, low oxidative roasting temperature not exceeding 600 ᵒC followed by acid leaching and roasting at 800 ᵒC gave the optimum condition for further steps of precipitation and calcination to finally achieve neodymium oxide.Keywords: NdFeB magnet waste, oxidative roasting, recycling, selective leaching
Procedia PDF Downloads 177812 Rethinking Urban Informality through the Lens of Inclusive Planning and Governance in Contemporary Cities: A Case Study of Johannesburg, South Africa
Authors: Blessings Masuku
Abstract:
Background: Considering that Africa is urbanizing faster than any other region globally, managing cities in the global South has become the centerpiece for the New Urban Agenda (i.e., a shared vision of how we rethink, rebuild, and manage our cities for a better and more sustainable future). This study is centered on governance and planning of urban informality practices with particular reference to the relationship between the state, informal actors (e.g., informal traders and informal dwellers), and other city stakeholders who are public space users (commuters, businesses, and environmental activists), and how informal actors organize themselves to lobby the state and claim for their rights in the city, and how they navigate their everyday livelihood strategies. Aim: The purpose of this study is to examine and interrogate contemporary approaches, policy and regulatory frameworks to urban spatial planning and management of informality in one of South Africa’s busiest and major cities, Johannesburg. Setting: The study uses the metropolitan region of the city of Johannesburg, South Africa to understand how this contemporary industrial city manages urban informality practices, including the use of public space, land zoning and street life, and paying a closer look at what progress has been made and gaps in their inclusive urban policy frameworks. Methods: This study utilized a qualitative approach that includes surveys (open-ended questions), archival research (i., e policy and other key document reviews), and key interviews mainly with city officials, and informality actors. A thematic analysis was used to analyze the data collected. Contribution: This study contributes to large urban informality scholarship in the global South cities by exploring how major cities particularly in Africa regulate and manage informality patterns and practices in their quest to build “utopian” smart cities. This study also brings a different perspective on the hacking ways used by the informal actors to resist harsh regulations and remain invisible in the city, which is something that previous literature has barely delved in-depth.Keywords: inclusive planning and governance, infrastructure systems, livelihood strategies urban informality, urban space
Procedia PDF Downloads 72811 PhD Students’ Challenges with Impact-Factor in Kazakhstan
Authors: Duishon Shamatov
Abstract:
This presentation is about Kazakhstan’s PhD students’ experiences with impact-factor publication requirement. Since the break-up of the USSR, Kazakhstan has been attempting to improve its higher education system at undergraduate and graduate levels. From March, 2010 Kazakhstan joined Bologna process and entered European space of higher education. To align with the European system of higher education, three level of preparation of specialists (undergraduate, master and PhD) was adopted to replace the Soviet system. The changes were aimed at promoting high quality higher education that meets the demands of labor market and growing needs of the industrial-innovative development of the country, and meeting the international standards. The shift to the European system has brought many benefits, but there are also some serious challenges. One of those challenges is related to the requirements for the PhD candidates to publish in national and international journals. Thus, a PhD candidate should have 7 publications in total, out of which one has to be in an international impact factor journal. A qualitative research was conducted to explore the PhD students’ views of their experiences with impact-factor publications. With the help of purposeful sampling, 30 PhD students from seven universities across Kazakhstan were selected for individual and focus group interviews. The key findings of the study are as follows. While the Kazakh PhD students have no difficulties in publishing in local journals, they face great challenges in attempting to publish in impact-factor journals for a range of reasons. They include but not limited to lack of research and publication skills, poorer knowledge of academic English, not familiarity with the peer review publication processes and expectations, and very short time to get published due to their PhD programme requirements. This situation is pushing some these young scholars explore alternative ways to get published in impact factor journals and they seek to publish by any means and often by any costs (which means even paying large sum of money for a publication). This in turn, creates a myth in the scholars’ circles in Kazakhstan, that to get published in impact factor journals, one should necessarily pay much money. This paper offers some policy recommendations on how to improve preparation of future PhD candidates in Kazakhstan.Keywords: Bologna process, impact-factor publications, post-graduate education, Kazakhstan
Procedia PDF Downloads 379810 Tool Wear of Metal Matrix Composite 10wt% AlN Reinforcement Using TiB2 Cutting Tool
Authors: M. S. Said, J. A. Ghani, C. H. Che Hassan, N. N. Wan, M. A. Selamat, R. Othman
Abstract:
Metal Matrix Composite (MMCs) have attracted considerable attention as a result of their ability to provide high strength, high modulus, high toughness, high impact properties, improved wear resistance and good corrosion resistance than unreinforced alloy. Aluminium Silicon (Al/Si) alloys Metal Matrix composite (MMC) has been widely used in various industrial sectors such as transportation, domestic equipment, aerospace, military, construction, etc. Aluminium silicon alloy is MMC reinforced with aluminium nitride (AlN) particle and becomes a new generation material for automotive and aerospace applications. The AlN material is one of the advanced materials with light weight, high strength, high hardness and stiffness qualities which have good future prospects. However, the high degree of ceramic particles reinforcement and the irregular nature of the particles along the matrix material that contribute to its low density, is the main problem that leads to the machining difficulties. This paper examines tool wear when milling AlSi/AlN Metal Matrix Composite using a TiB2 coated carbide cutting tool. The volume of the AlN reinforced particle was 10%. The milling process was carried out under dry cutting condition. The TiB2 coated carbide insert parameters used were the cutting speed of (230 m/min, feed rate 0.4mm tooth, DOC 0.5mm, 300 m/min, feed rate 0.8mm/tooth, DOC 0.5mm and 370 m/min, feed rate 0.8, DOC 0.4m). The Sometech SV-35 video microscope system was used for tool wear measurements respectively. The results have revealed that the tool life increases with the cutting speed (370 m/min, feed rate 0.8 mm/tooth and depth of cut 0.4mm) constituted the optimum condition for longer tool life which is 123.2 min. While at medium cutting speed, it is found that the cutting speed of 300m/min, feed rate 0.8 mm/tooth and depth of cut 0.5mm only 119.86 min for tool wear mean while the low cutting speed give 119.66 min. The high cutting speed gives the best parameter for cutting AlSi/AlN MMCs materials. The result will help manufacture to machining the AlSi/AlN MMCs materials.Keywords: AlSi/AlN Metal Matrix Composite milling process, tool wear, TiB2 coated carbide tool, manufacturing engineering
Procedia PDF Downloads 425809 Preservation and Promotion of Lao Traditional Food as Luangprabang Province Unique Culture and Tradition in Accordance With One District One Product Policy
Authors: Lamphong Volady
Abstract:
The primary purpose of this study was to explore the traditional cuisine (local food) of Luangprabang Province in line with the Lao PDR’s One District One Product Policy. Another purpose of the study was to examine channels used to present local food, reasons to preserve and promote local food, as well as local food preservation and promotion strategies. It also aimed at testing correlation hypotheses whether there is a statistically significant relationship between enjoyment of having local food and willingness to promote local cuisines becoming international cuisines, attractiveness to consume local food, preservation and promotion of local food problems, and local people’s occupations. The Convergent Parallel Mixed Methods were employed in this study. The results of the study showed that several local cuisines were found to be local food of Luangprabang Province, namely Jeow Bon (Chilli dipping suace), Or Lam or aw lahm (stew buffalo skin, herbs, Mai sakaan), Kai Pan (River Weed Dry), Tam Mak Houng Luangprabang (Papaya Salad), Nang (Yam Buffalo Skin Dry), Sai Oor (Sausage), Laap Sin Koay Sai Mar-Keua Pao (Beef Salad with Roasted Eggplants), Orm Born (Taro leaves Stew), Oor Nor Mai (Bamboo Shoot Sausage), Jeow Nam Poo (Pickled Crab Chillies), Mok Dok Kae (steaming or roasting a Dok Kae Wrapp), Nor Sa Wan, Kao Noom Kee Noo, Kao Noom Ba Bin. It also depicted that YouTube, Facebook, and TikTok were multiple social channels or platforms which were found to be used to introduce traditional food as well as television, smartphone, word of mouth, Lao food fairs and other provincial events. The study also found that local food should be preserved and promoted since traditional food is not only ancestral, ancient, traditional, and local cuisines, but it is also wisdom, unique, and national cuisine. The study also found that people feel attracted to consuming local food because local food is delicious, unique, clean, nutritious, non-contaminated and natural. The study showed that lack of funds to produce local food, inadequate draw materials, lack material to store products, insufficient place to produce and lack of related organizations engagement were found to be problems for preserving and promoting traditional food. Finally, the result of the study revealed that there is a statistically significant weak relationship between enjoyment of having local food and willingness to promote local cuisines becoming international cuisines (R²= 4.5%), (p-value <0.001). There is a statistically significant moderate relationship between enjoyment of having local food and attractiveness to consume local food (R²= 7.8%), (p-value <0.001). However, there is a statistically insignificant relationship between enjoyment of having local food and preservation and promotion of local food problems (R²= 1.8%), (p-value = 0.086). It was found that there is a statistically insignificant relationship between enjoyment of having local food and local people’s occupations (R²= 0.0%), (p-value = 0.929).Keywords: local food, preservation, promotion, traditional food, cuisines
Procedia PDF Downloads 77808 Exposure to Radon on Air in Tourist Caves in Bulgaria
Authors: Bistra Kunovska, Kremena Ivanova, Jana Djounova, Desislava Djunakova, Zdenka Stojanovska
Abstract:
The carcinogenic effects of radon as a radioactive noble gas have been studied and show a strong correlation between radon exposure and lung cancer occurrence, even in the case of low radon levels. The major part of the natural radiation dose in humans is received by inhaling radon and its progenies, which originates from the decay chain of U-238. Indoor radon poses a substantial threat to human health when build-up occurs in confined spaces such as homes, mines and caves and the risk increases with the duration of radon exposure and is proportional to both the radon concentration and the time of exposure. Tourist caves are a case of special environmental conditions that may be affected by high radon concentration. Tourist caves are a recognized danger in terms of radon exposure to cave workers (guides, employees working in shops built above the cave entrances, etc.), but due to the sensitive nature of the cave environment, high concentrations cannot be easily removed. Forced ventilation of the air in the caves is considered unthinkable due to the possible harmful effects on the microclimate, flora and fauna. The risks to human health posed by exposure to elevated radon levels in caves are not well documented. Various studies around the world often detail very high concentrations of radon in caves and exposure of employees but without a follow-up assessment of the overall impact on human health. This study was developed in the implementation of a national project to assess the potential health effects caused by exposure to elevated levels of radon in buildings with public access under the National Science Fund of Bulgaria, in the framework of grant No КП-06-Н23/1/07.12.2018. The purpose of the work is to assess the radon level in Bulgarian caves and the exposure of the visitors and workers. The number of caves (sampling size) was calculated for simple random selection from total available caves 65 (sampling population) are 13 caves with confidence level 95 % and confidence interval (margin of error) approximately 25 %. A measurement of the radon concentration in air at specific locations in caves was done by using CR-39 type nuclear track-etch detectors that were placed by the participants in the research team. Despite the fact that all of the caves were formed in karst rocks, the radon levels were rather different from each other (97–7575 Bq/m3). An assessment of the influence of the orientation of the caves in the earth's surface (horizontal, inclined, vertical) on the radon concentration was performed. Evaluation of health hazards and radon risk exposure causing by inhaling the radon and its daughter products in each surveyed caves was done. Reducing the time spent in the cave has been recommended in order to decrease the exposure of workers.Keywords: tourist caves, radon concentration, exposure, Bulgaria
Procedia PDF Downloads 189807 A Systematic Review Investigating the Use of EEG Measures in Neuromarketing
Authors: A. M. Byrne, E. Bonfiglio, C. Rigby, N. Edelstyn
Abstract:
Introduction: Neuromarketing employs numerous methodologies when investigating products and advertisement effectiveness. Electroencephalography (EEG), a non-invasive measure of electrical activity from the brain, is commonly used in neuromarketing. EEG data can be considered using time-frequency (TF) analysis, where changes in the frequency of brainwaves are calculated to infer participant’s mental states, or event-related potential (ERP) analysis, where changes in amplitude are observed in direct response to a stimulus. This presentation discusses the findings of a systematic review of EEG measures in neuromarketing. A systematic review summarises evidence on a research question, using explicit measures to identify, select, and critically appraise relevant research papers. Thissystematic review identifies which EEG measures are the most robust predictor of customer preference and purchase intention. Methods: Search terms identified174 papers that used EEG in combination with marketing-related stimuli. Publications were excluded if they were written in a language other than English or were not published as journal articles (e.g., book chapters). The review investigated which TF effect (e.g., theta-band power) and ERP component (e.g., N400) most consistently reflected preference and purchase intention. Machine-learning prediction was also investigated, along with the use of EEG combined with physiological measures such as eye-tracking. Results: Frontal alpha asymmetry was the most reliable TF signal, where an increase in activity over the left side of the frontal lobe indexed a positive response to marketing stimuli, while an increase in activity over the right side indexed a negative response. The late positive potential, a positive amplitude increase around 600 ms after stimulus presentation, was the most reliable ERP component, reflecting the conscious emotional evaluation of marketing stimuli. However, each measure showed mixed results when related to preference and purchase behaviour. Predictive accuracy was greatly improved through machine-learning algorithms such as deep neural networks, especially when combined with eye-tracking or facial expression analyses. Discussion: This systematic review provides a novel catalogue of the most effective use of each EEG measure commonly used in neuromarketing. Exciting findings to emerge are the identification of the frontal alpha asymmetry and late positive potential as markers of preferential responses to marketing stimuli. Predictive accuracy using machine-learning algorithms achieved predictive accuracies as high as 97%, and future research should therefore focus on machine-learning prediction when using EEG measures in neuromarketing.Keywords: EEG, ERP, neuromarketing, machine-learning, systematic review, time-frequency
Procedia PDF Downloads 111806 Variation of Biologically Active Compounds and Antioxidancy in the Process of Blueberry Storage
Authors: Meri Khakhutaishvili, Indira Djaparidze, Maia Vanidze, Aleko Kalandia
Abstract:
Cultivation of blueberry in Georgia started in 21st century. There are more than 20 species of blueberry cultivated in this region from all other the world. The species are mostly planted on acidic soil, previously occupied by tea plantations. Many of the plantations have pretty good yield. It is known that changing the location of a plant to a new soil or climate effects chemical compositions of the plant. However, even though these plants are brought from other countries, no research has been conducted to fully examine the blueberry fruit cultivated in Georgia. Shota Rustaveli National Science Foundation Grant FR/335/10-160/14, gave us an opportunity to continue our previous works and conduct research on several berries, among them of course the chemical composition of stored Blueberry. We were able to conduct the first study that included examining qualitative and quantitative features of bioactive compounds in Georgian Blueberry. This experiments were held in the ‘West Georgia Regional Chromatography center’ (Grant AP/96/13) of our university, that is equipped with modern equipment like HPLC UV-Vis, RI-detector, HPLC-conductivity detector, UPLC-MS-detector. Biochemical analysis was conducted using different physico-chemical and instrumental methods. Separation-identification and quantitative analysis were conducted using UPLC-MS (Waters Acquity QDa detector), HPLC (Waters Brceze 1525, UV-Vis 2489 detectors), pH-meters (Mettler Toledo). Refractrometer -Misco , Spectrometer –Cuvette Changer (Mettler Toledo UV5A), C18 Cartridge Solid Phase Extraction (SPE) Waters Sep-Pak C18 (500 mg), Chemicals – stability radical- 2,2-Diphenil-1-picrilhydrazyl (Aldrich-germany), Acetonitrile, Methanol, Acetic Acid (Merck-Germany), AlCl3, Folin Ciocalteu reagent (preparation), Standarts –Callic acid, Quercetin. Carbohydrate HPLC-RI analysis used systems acetonitrile-water (80-20). UPLC-MS analysis used systems- solvent A- Water +1 % acetic acid და solvent -B Methanol +1% acetic acid). It was concluded that the amount of sugars was in range of 5-9 %, mostly glucose and fructose. Also, the amount of organic acids was 0.2-1.2% most of which was malic and citric acid. Anthocians were also present in the sample 200-550mg/100g. We were able to identify up to 15 different compounds, most of which were products of delphinidine and cyanide. All species have high antioxidant level(DPPH). By rapidly freezing the sample and then keeping it in specific conditions allowed us to keep the sample for 12 months.Keywords: antioxidants, bioactive, blueberry, storage
Procedia PDF Downloads 212805 Methylphenidate Use by Canadian Children and Adolescents and the Associated Adverse Reactions
Authors: Ming-Dong Wang, Abigail F. Ruby, Michelle E. Ross
Abstract:
Methylphenidate is a first-line treatment drug for attention deficit hyperactivity disorder (ADHD), a common mental health disorder in children and adolescents. Over the last several decades, the rate of children and adolescents using ADHD medication has been increasing in many countries. A recent study found that the prevalence of ADHD medication use among children aged 3-18 years increased in 13 different world regions between 2001 and 2015, where the absolute increase ranged from 0.02 to 0.26% per year. The goal of this study was to examine the use of methylphenidate in Canadian children and its associated adverse reactions. Methylphenidate use information among young Canadians aged 0-14 years was extracted from IQVIA data on prescriptions dispensed by pharmacies between April 2014 and June 2020. The adverse reaction information associated with methylphenidate use was extracted from the Canada Vigilance database for the same time period. Methylphenidate use trends were analyzed based on sex, age group (0-4 years, 5-9 years, and 10-14 years), and geographical location (province). The common classes of adverse reactions associated with methylphenidate use were sorted, and the relative risks associated with methylphenidate use as compared with two second-line amphetamine medications for ADHD were estimated. This study revealed that among Canadians aged 0-14 years, every 100 people used about 25 prescriptions (or 23,000 mg) of methylphenidate per year during the study period, and the use increased with time. Boys used almost three times more methylphenidate than girls. The amount of drug used was inversely associated with age: Canadians aged 10-14 years used nearly three times as many drugs compared to those aged 5-9 years. Seasonal methylphenidate use patterns were apparent among young Canadians, but the seasonal trends differed among the three age groups. Methylphenidate use varied from region to region, and the highest methylphenidate use was observed in Quebec, where the use of methylphenidate was at least double that of any other province. During the study period, Health Canada received 304 adverse reaction reports associated with the use of methylphenidate for Canadians aged 0-14 years. The number of adverse reaction reports received for boys was 3.5 times higher than that for girls. The three most common adverse reaction classes were psychiatric disorders, nervous system disorders and injury, poisoning procedural complications. The number one commonly reported adverse reaction for boys was aggression (11.2%), while for girls, it was a tremor (9.6%). The safety profile in terms of adverse reaction classes associated with methylphenidate use was similar to that of the selected control products. Methylphenidate is a commonly used pharmaceutical product in young Canadians, particularly in the province of Quebec. Boys used approximately three times more of this product as compared to girls. Future investigation is needed to determine what factors are associated with the observed geographic variations in Canada.Keywords: adverse reaction risk, methylphenidate, prescription trend, use variation
Procedia PDF Downloads 160804 Intensification of Heat Transfer Using AL₂O₃-Cu/Water Hybrid Nanofluid in a Circular Duct Using Inserts
Authors: Muluken Biadgelegn Wollele, Mebratu Assaye Mengistu
Abstract:
Nanotechnology has created new opportunities for improving industrial efficiency and performance. One of the proposed approaches to improving the effectiveness of temperature exchangers is the use of nanofluids to improve heat transfer performance. The thermal conductivity of nanoparticles, as well as their size, diameter, and volume concentration, all played a role in influencing the rate of heat transfer. Nanofluids are commonly used in automobiles, energy storage, electronic component cooling, solar absorbers, and nuclear reactors. Convective heat transfer must be improved when designing thermal systems in order to reduce heat exchanger size, weight, and cost. Using roughened surfaces to promote heat transfer has been tried several times. Thus, both active and passive heat transfer methods show potential in terms of heat transfer improvement. There will be an added advantage of enhanced heat transfer due to the two methods adopted; however, pressure drop must be considered during flow. Thus, the current research aims to increase heat transfer by adding a twisted tap insert in a plain tube using a working fluid hybrid nanofluid (Al₂O₃-Cu) with a base fluid of water. A circular duct with inserts, a tube length of 3 meters, a hydraulic diameter of 0.01 meters, and tube walls with a constant heat flux of 20 kW/m² and a twist ratio of 125 was used to investigate Al₂O₃-Cu/H₂O hybrid nanofluid with inserts. The temperature distribution is better than with conventional tube designs due to stronger tangential contact and swirls in the twisted tape. The Nusselt number values of plain twisted tape tubes are 1.5–2.0 percent higher than those of plain tubes. When twisted tape is used instead of plain tube, performance evaluation criteria improve by 1.01 times. A heat exchanger that is useful for a number of heat exchanger applications can be built utilizing a mixed flow of analysis that incorporates passive and active methodologies.Keywords: nanofluids, active method, passive method, Nusselt number, performance evaluation criteria
Procedia PDF Downloads 74803 Health Risk Assessment of Exposing to Benzene in Office Building around a Chemical Industry Based on Numerical Simulation
Authors: Majid Bayatian, Mohammadreza Ashouri
Abstract:
Releasing hazardous chemicals is one of the major problems for office buildings in the chemical industry and, therefore, environmental risks are inherent to these environments. The adverse health effects of the airborne concentration of benzene have been a matter of significant concern, especially in oil refineries. The chronic and acute adverse health effects caused by benzene exposure have attracted wide attention. Acute exposure to benzene through inhalation could cause headaches, dizziness, drowsiness, and irritation of the skin. Chronic exposures have reported causing aplastic anemia and leukemia at the occupational settings. Association between chronic occupational exposure to benzene and the development of aplastic anemia and leukemia were documented by several epidemiological studies. Numerous research works have investigated benzene emissions and determined benzene concentration at different locations of the refinery plant and stated considerable health risks. The high cost of industrial control measures requires justification through lifetime health risk assessment of exposed workers and the public. In the present study, a Computational Fluid Dynamics (CFD) model has been proposed to assess the exposure risk of office building around a refinery due to its release of benzene. For simulation, GAMBIT, FLUENT, and CFD Post software were used as pre-processor, processor, and post-processor, and the model was validated based on comparison with experimental results of benzene concentration and wind speed. Model validation results showed that the model is highly validated, and this model can be used for health risk assessment. The simulation and risk assessment results showed that benzene could be dispersion to an office building nearby, and the exposure risk has been unacceptable. According to the results of this study, a validated CFD model, could be very useful for decision-makers for control measures and possibly support them for emergency planning of probable accidents. Also, this model can be used to assess exposure to various types of accidents as well as other pollutants such as toluene, xylene, and ethylbenzene in different atmospheric conditions.Keywords: health risk assessment, office building, Benzene, numerical simulation, CFD
Procedia PDF Downloads 130