Search results for: non-point source pollutants
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5275

Search results for: non-point source pollutants

4195 Impact of Ship Traffic to PM 2.5 and Particle Number Concentrations in Three Port-Cities of the Adriatic/Ionian Area

Authors: Daniele Contini, Antonio Donateo, Andrea Gambaro, Athanasios Argiriou, Dimitrios Melas, Daniela Cesari, Anastasia Poupkou, Athanasios Karagiannidis, Apostolos Tsakis, Eva Merico, Rita Cesari, Adelaide Dinoi

Abstract:

Emissions of atmospheric pollutants from ships and harbour activities are a growing concern at International level given their potential impacts on air quality and climate. These close-to-land emissions have potential impact on local communities in terms of air quality and health. Recent studies show that the impact of maritime traffic to atmospheric particulate matter concentrations in several coastal urban areas is comparable with the impact of road traffic of a medium size town. However, several different approaches have been used for these estimates making difficult a direct comparison of results. In this work an integrated approach based on emission inventories and dedicated measurement campaigns has been applied to give a comparable estimate of the impact of maritime traffic to PM2.5 and particle number concentrations in three major harbours of the Adriatic/Ionian Seas. The influences of local meteorology and of the logistic layout of the harbours are discussed.

Keywords: ship emissions, PM2.5, particle number concentrations, impact of shipping to atmospheric aerosol

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4194 Patterns and Extent of Self-Medication Practice among Adolescents in Selected Public Secondary Schools in IFE Central Local Government Area of Osun State, Nigeria

Authors: Olajumoke A. Ojeleye

Abstract:

The study assessed the patterns and extent of self-medication practice among adolescents in selected public senior secondary schools in Ife Central Local Government Area of Osun State. The objectives of the study were to find out the patterns of self-medication among adolescents, to elucidate whether age or gender has any effect on the self-medication patterns of adolescent, to ascertain to what extent adolescents indulge in self-medication, to examine the sources of drug information of these adolescents and also to examine the sources of these drugs. A cross-sectional design was employed for the study. A self-administered questionnaire tested for validity was used to collect data. Multistage sampling technique was used and 238 adolescents participated in the study. Data collection took two weeks and was analysed using Statistical Package for Social Sciences version 17. Results were presented using descriptive (e.g. frequency counts) and inferential statistics (e.g. chi-square). Results showed that more females (55.9%) than males (44.1%) practiced self-medication. Although the results showed that there is a low prevalence rate (33.6%) of self-medication among adolescents, chemists served as both the source of information on how to use the drug as well as the source of the drugs. Also, adolescents under study will only self-medicate in medical conditions such as malaria or wound/injuries but will prefer to see a doctor for conditions such as abdominal pain, infections or allergic reactions. It was recommended that government officials responsible for regulating and controlling of drugs should be more active in ensuring that safe drugs are made available over the counter and the consumer be given adequate information about the use of drugs and when to consult the doctor.

Keywords: adolescents, drugs, patterns, self-medication

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4193 Transferring Cultural Meanings: A Case of Translation Classroom

Authors: Ramune Kasperaviciene, Jurgita Motiejuniene, Dalia Venckiene

Abstract:

Familiarising students with strategies for transferring cultural meanings (intertextual units, culture-specific idioms, culture-specific items, etc.) should be part of a comprehensive translator training programme. The present paper focuses on strategies for transferring such meanings into other languages and explores possibilities for introducing these methods and practice to translation students. The authors (university translation teachers) analyse the means of transferring cultural meanings from English into Lithuanian in a specific travel book, attribute these means to theoretically grounded strategies, and make calculations related to the frequency of adoption of specific strategies; translation students are familiarised with concepts and methods related to transferring cultural meanings and asked to put their theoretical knowledge into practice, i.e. interpret and translate certain culture-specific items from the same source text, and ground their decisions on theory; the comparison of the strategies employed by the professional translator of the source text (as identified by the authors of this study) and by the students is made. As a result, both students and teachers gain valuable experience, and new practices of conducting translation classes for a specific purpose evolve. Conclusions highlight the differences and similarities of non-professional and professional choices, summarise the possibilities for introducing methods of transferring cultural meanings to students, and round up with specific considerations of the impact of theoretical knowledge and the degree of experience on decisions made in the translation process.

Keywords: cultural meanings, culture-specific items, strategies for transferring cultural meanings, translator training

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4192 Railway Transport as a Potential Source of Polychlorinated Biphenyls in Soil

Authors: Nataša Stojić, Mira Pucarević, Nebojša Ralević, Vojislava Bursić, Gordan Stojić

Abstract:

Surface soil (0 – 10 cm) samples from 52 sampling sites along the length of railway tracks on the territory of Srem (the western part of the Autonomous Province of Vojvodina, itself part of Serbia) were collected and analyzed for 7 polychlorinated biphenyls (PCBs) in order to see how the distance from the railroad on the one hand and dump on the other hand, affect the concentration of PCBs (CPCBs) in the soil. Samples were taken at a distance of 0.03 to 4.19 km from the railway and 0.43 to 3.35 km from the landfills. For the soil extraction the Soxhlet extraction (USEPA 3540S) was used. The extracts were purified on a silica-gel column (USEPA 3630C). The analysis of the extracts was performed by gas chromatography with tandem mass spectrometry. PCBs were not detected only at two locations. Mean total concentration of PCBs for all other sampling locations was 0,0043 ppm dry weight (dw) with a range of 0,0005 to 0,0227 ppm dw. On the part of the data that were interesting for this research with statistical methods (PCA) were isolated factors that affect the concentration of PCBs. Data were also analyzed using the Pearson's chi-squared test which showed that the hypothesis of independence of CPCBs and distance from the railway can be rejected. Hypothesis of independence between CPCB and the percentage of humus in the soil can also be rejected, in contrast to dependence of CPCB and the distance from the landfill where the hypothesis of independence cannot be rejected. Based on these results can be said that railway transport is a potential source of PCBs. The next step in this research is to establish the position of transformers which are located near sampling sites as another important factor that affects the concentration of PCBs in the soil.

Keywords: GC/MS, landfill, PCB, railway, soil

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4191 Evaluation of Shale Gas Resource Potential of Cambay Basin, Gujarat, India

Authors: Vaishali Sharma, Anirbid Sircar

Abstract:

Energy is one of the most eminent and fundamental strategic commodity, scarcity of which may poses great impact on the functioning of the entire commodity. According to the present study, the estimated reserves of gas in India as on 31.03.2015 stood at 1427.15 BCM. It is expected that the gas demand is set to grow significantly at a CAGR of 7% from 226.7 MMSCMD in 2012-13 to 713.5 MMSCMD in 2009-30. To bridge the gap between the demand and supply of energy, the interest towards the exploration and exploitation of unconventional resources like – Shale gas, Coal bed methane, Gas hydrates, tight gas etc has immensed. Nowadays, Shale gas prospects are emerging rapidly as a promising energy source globally. The United States of America (USA) has 240 TCF of proved reserves of shale gas and presently contributed more than 17% of total gas production. As compared to USA, shale gas production in India is at nascent stage. A resource potential of around 2000 TCF is estimated and according to preliminary data analysis, basins like Gondwana, Cambay, Krishna – Godavari, Cauvery, Assam-Arakan, Rajasthan, Vindhyan, and Bengal are the most promising shale gas basins. In the present study, the careful evaluation of Cambay Shale (Indian Shale) properties like geological age, lithology, depth, organically rich thickness, TOC, thermal maturity, porosity, permeability, clay content, quartz content, Kerogen type, Hydrocarbon window etc. has been done. And then the detailed comparison of Indian shale with USA shale will be discussed. This study investigates qualitative and quantitative nature of potential shale basins which will be helpful from exploration and exploitation point of view.

Keywords: shale, shale gas, energy source, lithology

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4190 Thermal Decontamination of Soils Polluted by Polychlorinated Biphenyls and Microplastics

Authors: Roya Biabani, Mentore Vaccari, Piero Ferrari

Abstract:

Accumulated microplastic (MPLs) in soil pose the risk of adsorbing and transporting polychlorinated biphenyls (PCBs) into the food chain or bodies. PCBs belong to a class of man-made hydrophobic organic chemicals (HOCs) that are classified as probable human carcinogens and a hazard to biota. Therefore, to take effective action and not aggravate the already recognized problems, the knowledge of PCB remediation in the presence of MPLs needs to be complete. Due to the high efficiency and little secondary pollution production, thermal desorption (TD) has been widely used for processing a variety of pollutants, especially for removing volatile and semi-volatile organic matter from contaminated solids and sediment. This study investigates the fate of PCB compounds during the thermal remediation method. For this, the PCB-contaminated soil was collected from the earth-canal downstream Caffaro S.p.A. chemical factory, which produced PCBs and PCB mixtures between 1930 and 1984. For MPL analysis, MPLs were separated by density separation and oxidation of organic matter. An operational range for the key parameters of thermal desorption processes was experimentally evaluated. Moreover, the temperature treatment characteristics of the PCBs-contaminated soil under anaerobic and aerobic conditions were studied using the Thermogravimetric Analysis (TGA).

Keywords: contaminated soils, microplastics, polychlorinated biphenyls, thermal desorption

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4189 Kinetics Analysis of Lignocellulose Hydrolysis and Glucose Consumption Using Aspergillus niger in Solid State

Authors: Akida Mulyaningtyas, Wahyudi Budi Sediawan

Abstract:

One decisive stage in bioethanol production from plant biomass is the hydrolysis of lignocellulosic materials into simple sugars such as glucose. The produced glucose is then fermented into ethanol. This stage is popularly done in biological method by using cellulase that is produced by certain fungi. As it is known, glucose is the main source of nutrition for most microorganisms. Therefore, cutting cellulose into glucose is actually an attempt of microorganism to provide nutrition for itself. So far, this phenomenon has received less attention while it is necessary to identify the quantity of sugar consumed by the microorganism. In this study, we examined the phenomenon of sugar consumption by microorganism on lignocellulosic hydrolysis. We used oil palm empty fruit bunch (OPEFB) as the source of lignocellulose and Aspergillus niger as cellulase-producing fungus. In Indonesia, OPEFB is plantation waste that is difficult to decompose in nature and causes environmental problems. First, OPEFB was pretreated with 1% of NaOH at 170 oC to destroy lignin that hindered A.niger from accessing cellulose. The hydrolysis was performed by growing A.niger on pretreated OPEFB in solid state to minimize the possibility of contamination. The produced glucose was measured every 24 hours for 9 days. We analyzed the kinetics of both reactions, i.e., hydrolysis and glucose consumption, simultaneously. The constants for both reactions were assumed to follow the Monod equation. The results showed that the reaction constant of glucose consumption (μC) was higher than of cellulose hydrolysis (μH), i.e., 11.8 g/L and 0.62 g/L for glucose consumption and hydrolysis respectively. However, in general, the reaction rate of hydrolysis is greater than of glucose consumption since the cellulose concentration as substrate in hydrolysis is much higher than glucose as substrate in the consumption reaction.

Keywords: Aspergillus niger, bioethanol, hydrolysis, kinetics

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4188 Geochemistry and Petrogenesis of Anorogenic Acid Plutonic Rocks of Khanak and Devsar of Southwestern Haryana

Authors: Naresh Kumar, Radhika Sharma, A. K. Singh

Abstract:

Acid plutonic rocks from the Khanak and Devsar areas of southwestern Haryana were investigated to understand their geochemical and petrogenetic characteristics and tectonic environments. Three dominant rock types (grey, grayish green and pink granites) are the principal geochemical features of Khanak and Devsar areas which reflect the dependencies of their composition on varied geological environment during the anorogenic magmatism. These rocks are enriched in SiO₂, Na₂O+K₂O, Fe/Mg, Rb, Zr, Y, Th, U, REE (Rare Earth Elements) enriched and depleted in MgO, CaO, Sr, P, Ti, Ni, Cr, V and Eu and exhibit a clear affinity to the within-plate granites that were emplaced in an extensional tectonic environment. Chondrite-normalized REE patterns show enriched LREE (Light Rare Earth Elements), moderate to strong negative Eu anomalies and flat heavy REE and grey and grayish green is different from pink granite which is enriched by Rb, Ga, Nb, Th, U, Y and HREE (Heavy Rare Earth Elements) concentrations. The composition of parental magma of both areas corresponds to mafic source contaminated with crustal materials. Petrogenetic modelling suggest that the acid plutonic rocks might have been generated from a basaltic source by partial melting (15-25%) leaving a residue with 35% plagioclase, 25% alkali feldspar, 25% quartz, 7% orthopyroxene, 5% biotite and 3% hornblende. Granites from both areas might be formed from different sources with different degree of melting for grey, grayish green and pink granites.

Keywords: A-type granite, anorogenic, Malani igneous suite, Khanak and Devsar

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4187 Acoustics Barrier Design to Reduce Railway Noise by Using Maekawa's Method

Authors: Malinda Sabrina, Khoerul Anwar

Abstract:

Railway noise generated by pass-by train has been described as a form of environmental pollutants especially for the residential area near the railway. Many studies have shown, that environmental noise particularly transportation noise has negative effects on people which resulting in annoyance and specific health problems such as cardiovascular disease, cognitive impairment and sleep disturbance. Therefore, various attempts are made to reduce the noise. One method of reducing such noise to acceptable noise levels is to build acoustically barrier walls. The objective of this study was to review the method of reducing railway noise and obtain the preliminary design of the acoustics barrier on the edge of railway tracks close to the residential area. The design of this barrier is using the Maekawa's method. Measurements have been performed in residential areas around the railroads in the Karawang - Indonesia with the absence of an acoustical barrier. From the observation, it was found that the railway was passed by five trains within thirty minutes. With the limited distance between the railway tracks and the location of the residential area as well as the street of residents, then it was obtained that a reduction in sound pressure level is 25 dBA. Maximum sound pressure level obtained is 86.9 dBA then by setting the barrier as high as 4 m at a distance, 2.5 m from the railway, the noise level received by residents in the settlement around the railway line becomes 61.9 dBA.

Keywords: acoustics barrier, Maekawa's method, noise attenuation, railway noise

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4186 Assessment of Environmental Impact of Rain Water and Industrial Water Leakage in the Libyan Iron and Steel Company in the Sea Water

Authors: Mohamed Alzarug Aburugba, Rashid Mohamed Eltanashi

Abstract:

Rainwater is considered an essential water resource, as it contributes to filling the deficit in water resources, especially in countries that suffer from a scarcity of natural water sources. One of the important issues facing the Water and Gas Services Department at the Libyan Iron and Steel Company is the large loss of quantities of industrial water, both direct and indirect cooling water (DCW, ICW), produced within the company due to leaks in the cooling systems of the factories of the Libyan Iron and Steel Company. These amounts of polluted industrial water leakage are mixed with rainwater collected by stormwater stations (6 stations) in LISCO, which is pumped to the sea through pumps with a very high flow rate, and thus, this will carry a lot of waste, heavy metals, and oils to the sea, which negatively affects marine environmental resources. This paper assesses the environmental impact of the quantities of rainwater and mixed industrial water in stormwater stations in the Libyan Iron and Steel Company and methods of mitigation, treating pollutants and reusing them as industrial water in the production processes of the steel industry.

Keywords: rainwater, mitigation, impact, sewage, heavy metals, assessment, pollution, environment, natural resources, industrial water.

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4185 Border Between the Violation of Dental Ethics and the Occurrence of Dental Malpractice

Authors: Saimir Heta, Rialda Xhizdari, Kers Kapaj, Ilma Robo

Abstract:

Background: The interests of both individuals involved, both the dentist with his professionalism, and the patient who claims and expects the proper professional dental service, are determined in cases of dental malpractice. The latter is a phenomenon that is also wearing the "cloak" of bilateral manipulations, which in themselves require strong legal control to regulate the relations between the involved parties. The two individuals are involved both individually and even professionally and emotionally, with support in the "ultimate" interests of the two people, which in the case of conflicts or grievances, which as a result are transported to the family or society of the affected individual. Main text: The reason for malpractice is the most difficult part to find and then to interpret. It can be professional in the view of "so much I know how to do, so much done", or in the view of the impossibility of individual health conditions to achieve high professional expectations. But, the reason can also be individual with the intention of doing bad without reason or with the source of an unhealthy mind and the source of malicious thinking. The professional himself is a human being and as such may be under the effect of individual treatments or vices, therefore causing misuse, a case that must be distinguished from intentional misuse and which must be judged for the results or damages caused by the professional based on criminal law. Conclusions: Malpractice in some cases may be unavoidable, beyond the good intention of the dental intervention, which should be well understood by both parties involved in this relationship. Malpractice is not necessarily related only to difficult clinical cases, but sometimes also appears as a random deviation of a dental treatment with a welldefined professional protocol. The legal support in the interpretation of malpractice cases should be much more specific according to previous cases, this practice specifically, perhaps also according to different religious states.

Keywords: dental ethics, malpractice, professional dental service, legal support

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4184 Dairy Wastewater Remediation Using Electrochemical Oxidation on Boron Doped Diamond (BDD) Anode

Authors: Arwa Abdelhay, Inshad Jum’h, Abeer Albsoul, Khalideh Alrawashdeh, Dina Al Tarazi

Abstract:

Treated wastewater reuse has been considered recently as one of the successful management strategies to overcome water shortage in countries suffering from water scarcity. The non-readily biodegradable and recalcitrant pollutants in wastewater cannot be destructed by conventional treatment methods. This paper deals with the electrochemical treatment of dairy wastewater using a promising non-conventional Boron-Doped Diamond (BDD) anode. During the electrochemical process, different operating parameters were investigated, such as electrolysis time, current density, supporting electrolyte, chemical oxygen demand (COD), turbidity as well as absorbance/color. The experimental work revealed that electrochemical oxidation carried out with no added electrolyte has significantly reduced the COD, turbidity, and color (absorbance) by 72%, 76%, and 78% respectively. Results also showed that raising the current density from 5.1 mA/cm² to 7.7 mA/cm² has boosted COD, and color removal to 82.5%, and 83% respectively. However, the current density did not show any significant effect on the turbidity. Interestingly, it was observed that adding Na₂SO₄ and FeCl₃ as supporting electrolytes brought the COD removal to 91% and 97% respectively. Likewise, turbidity and color removal has been enhanced by the addition of the same supporting electrolytes.

Keywords: boron doped-diamond anode, dairy wastewater, electrochemical oxidation, supporting electrolytes

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4183 Systematic Literature Review and Bibliometric Analysis of Interorganizational Employee Mobility Determinants

Authors: Iva Zdrilić, Petra Došenović Bonča, Darija Aleksić

Abstract:

Since the boundaryless career, with its emphasis on cross-employer movements, was introduced as a new paradigm of career development, inter-organizational employee mobility has been increasing. Although this phenomenon may have positive implications for individual careers and destination organizations, the consequences for the source organizations losing workers are less clear. The aim of this paper is thus to develop a comprehensive typology of possible inter-organizational employee mobility determinants. Since the most common classification differentiates between mobility determinants at different levels (i.e., economic, organizational, and individual), this paper focuses on building a comprehensive multi-level typology of inter-organizational mobility determinants across diverse sectors and industries. By using a structured literature review approach and bibliometric analysis, the paper reveals both intricate relationships between different mobility determinants and the complexity of inter-organizational networks and social ties. The latter appears as both a mobility determinant (at the organizational and individual level) and a mobility effect. Indeed, inter-organizational employee mobility leads to the formation of networks between source and destination organizations. These networks are practically based on the social ties between mobile employees and their colleagues and, in this way, they close the "inter-organizational employee mobility - inter-organizational network/ties" circle. The paper contributes to the career development literature by uncovering hitherto underexplored diverse determinants of intra- and inter-sectoral mobility as well as the conflicting results of the existing studies on some factors (e.g., inter-organizational networks and/or social ties) that appear both as a mobility determinant and a mobility effect.

Keywords: inter-organizational mobility, social ties, inter-organizational network, knowledge transfer

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4182 Contribution of Income Diversification to Total Rural Households Income in the Upper East Region, Ghana

Authors: Yakubu Abdulai, Kenichi Matsui

Abstract:

The agricultural industry has faced a variety of challenges in meeting the expanding income demand of the rural population. As a result, rural households must diversify their income sources to meet their income demand. Although income diversification strategies help rural households, it contributes to total household income, and the socio-demographic determinants are not known in the Upper East Region of Ghana. For these reasons, the purpose of this study was to determine the contribution of income diversification strategies to household income and the socio-demographic factors influencing it. We conducted a questionnaire survey among 360 rural households in the Upper East Region of Ghana. We asked about their socio-demographic information, their choice of income diversification strategies, and their remittances through rural-city migration. The questionnaire survey findings demonstrate that the main livelihood income source contributes 22%, and on-farm income diversification contributes the most to household total income (47%), followed by non-farm diversification income (16%) and off-farm diversification income (15%). Calculations from the income diversity index showed that the average income diversification strategy was 0.5 out of 1. The calculation of the income dependence index also showed that the average dependent on a particular source of income was 0.2 out of 1. All the respondents said household members temporarily migrate to contribute to household income through remittances. The results further reveal that their choice of income diversification is influenced by their age, educational background, experience, and farm size. The paper recommends the promotion of rural development policies that increase income-generating activities and educate rural households on how to increase returns from their investment.

Keywords: income diversification, poverty alleviation, rural households, upper east region

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4181 Ultrasound-Assisted Soil Washing Process for the Removal of Heavy Metals from Clays

Authors: Sophie Herr, Antoine Leybros, Yves Barre, Sergey Nikitenko, Rachel Pflieger

Abstract:

The proportion of soil contaminated by a wide range of pollutants (heavy metals, PCBs, pesticides, etc.) of anthropogenic origin is constantly increasing, and it is becoming urgent to address this issue. Among remediation methods, soil washing is an effective, relatively fast, and widely used process. This study assesses its coupling with ultrasound: indeed, sonication induces the formation of cavitation bubbles in solution that enhance local mass transfer through agitation and particle erosion. The removal of target toxic elements Ni(II) and Zn(II) from vermiculite clay has been studied under 20 kHz ultrasound and silent conditions. Several acids were tested, and HCl was chosen as the solvent. The effects of solid/liquid ratio and particle size were investigated. Metal repartition in the clay has been followed by Tessier's sequential extraction procedure. The results showed that more metal elements bound to the challenging residual phase were desorbed with 20 kHz ultrasound than in silent conditions. This supports the promising application of ultrasound for heavy metal desorption in difficult conditions. Further experiments were performed at high-frequency US (362 kHz), and it was shown that fragmentation of the vermiculite particles is then limited, while positive effects of US in the decontamination are kept.

Keywords: desorption, heavy metals, ultrasound, vermiculite

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4180 Design and Simulation of a Radiation Spectrometer Using Scintillation Detectors

Authors: Waleed K. Saib, Abdulsalam M. Alhawsawi, Essam Banoqitah

Abstract:

The idea of this research is to design a radiation spectrometer using LSO scintillation detector coupled to a C series of SiPM (silicon photomultiplier). The device can be used to detects gamma and X-ray radiation. This device is also designed to estimates the activity of the source contamination. The SiPM will detect light in the visible range above the threshold and read them as counts. Three gamma sources were used for these experiments Cs-137, Am-241 and Co-60 with various activities. These sources are applied for four experiments operating the SiPM as a spectrometer, energy resolution, pile-up set and efficiency. The SiPM is connected to a MCA to perform as a spectrometer. Cerium doped Lutetium Silicate (Lu₂SiO₅) with light yield 26000 photons/Mev coupled with the SiPM. As a result, all the main features of the Cs-137, Am-241 and Co-60 are identified in MCA. The experiment shows how photon energy and probability of interaction are inversely related. Total attenuation reduces as photon energy increases. An analytical calculation was made to obtain the FWHM resolution for each gamma source. The FWHM resolution for Am-241 (59 keV) is 28.75 %, for Cs-137 (662 keV) is 7.85 %, for Co-60 (1173 keV) is 4.46 % and for Co-60 (1332 keV) is 3.70%. Moreover, the experiment shows that the dead time and counts number decreased when the pile-up rejection was disabled and the FWHM decreased when the pile-up was enabled. The efficiencies were calculated at four different distances from the detector 2, 4, 8 and 16 cm. The detection efficiency was observed to declined exponentially with increasing distance from the detector face. Conclusively, the SiPM board operated with an LSO scintillator crystal as a spectrometer. The SiPM energy resolution for the three gamma sources used was a decent comparison to other PMTs.

Keywords: PMT, radiation, radiation detection, scintillation detectors, silicon photomultiplier, spectrometer

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4179 Metal Contamination in an E-Waste Recycling Community in Northeastern Thailand

Authors: Aubrey Langeland, Richard Neitzel, Kowit Nambunmee

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Electronic waste, ‘e-waste’, refers generally to discarded electronics and electrical equipment, including products from cell phones and laptops to wires, batteries and appliances. While e-waste represents a transformative source of income in low- and middle-income countries, informal e-waste workers use rudimentary methods to recover materials, simultaneously releasing harmful chemicals into the environment and creating a health hazard for themselves and surrounding communities. Valuable materials such as precious metals, copper, aluminum, ferrous metals, plastic and components are recycled from e-waste. However, persistent organic pollutants such as polychlorinated biphenyls (PCBs) and some polybrominated diphenyl ethers (PBDEs), and heavy metals are toxicants contained within e-waste and are of great concern to human and environmental health. The current study seeks to evaluate the environmental contamination resulting from informal e-waste recycling in a predominantly agricultural community in northeastern Thailand. To accomplish this objective, five types of environmental samples were collected and analyzed for concentrations of eight metals commonly associated with e-waste recycling during the period of July 2016 through July 2017. Rice samples from the community were collected after harvest and analyzed using inductively coupled plasma mass spectrometry (ICP-MS) and gas furnace atomic spectroscopy (GF-AS). Soil samples were collected and analyzed using methods similar to those used in analyzing the rice samples. Surface water samples were collected and analyzed using absorption colorimetry for three heavy metals. Environmental air samples were collected using a sampling pump and matched-weight PVC filters, then analyzed using Inductively Coupled Argon Plasma-Atomic Emission Spectroscopy (ICAP-AES). Finally, surface wipe samples were collected from surfaces in homes where e-waste recycling activities occur and were analyzed using ICAP-AES. Preliminary1 results indicate that some rice samples have concentrations of lead and cadmium significantly higher than limits set by the United States Department of Agriculture (USDA) and the World Health Organization (WHO). Similarly, some soil samples show levels of copper, lead and cadmium more than twice the maximum permissible level set by the USDA and WHO, and significantly higher than other areas of Thailand. Surface water samples indicate that areas near e-waste recycling activities, particularly the burning of e-waste products, result in increased levels of cadmium, lead and copper in surface waters. This is of particular concern given that many of the surface waters tested are used in irrigation of crops. Surface wipe samples measured concentrations of metals commonly associated with e-waste, suggesting a danger of ingestion of metals during cooking and other activities. Of particular concern is the relevance of surface contamination of metals to child health. Finally, air sampling showed that the burning of e-waste presents a serious health hazard to workers and the environment through inhalation and deposition2. Our research suggests a need for improved methods of e-waste recycling that allows workers to continue this valuable revenue stream in a sustainable fashion that protects both human and environmental health. 1Statistical analysis to be finished in October 2017 due to follow-up field studies occurring in July and August 2017. 2Still awaiting complete analytic results.

Keywords: e-waste, environmental contamination, informal recycling, metals

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4178 Triple Intercell Bar for Electrometallurgical Processes: A Design to Increase PV Energy Utilization

Authors: Eduardo P. Wiechmann, Jorge A. Henríquez, Pablo E. Aqueveque, Luis G. Muñoz

Abstract:

PV energy prices are declining rapidly. To take advantage of the benefits of those prices and lower the carbon footprint, operational practices must be modified. Undoubtedly, it challenges the electrowinning practice to operate at constant current throughout the day. This work presents a technology that contributes in providing modulation capacity to the electrode current distribution system. This is to raise the day time dc current and lower it at night. The system is a triple intercell bar that operates in current-source mode. The design is a capping board free dogbone type of bar that ensures an operation free of short circuits, hot swapability repairs and improved current balance. This current-source system eliminates the resetting currents circulating in equipotential bars. Twin auxiliary connectors are added to the main connectors providing secure current paths to bypass faulty or impaired contacts. All system conductive elements are positioned over a baseboard offering a large heat sink area to the ventilation of a facility. The system works with lower temperature than a conventional busbar. Of these attributes, the cathode current balance property stands out and is paramount for day/night modulation and the use of photovoltaic energy. A design based on a 3D finite element method model predicting electric and thermal performance under various industrial scenarios is presented. Preliminary results obtained in an electrowinning facility with industrial prototypes are included.

Keywords: electrowinning, intercell bars, PV energy, current modulation

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4177 Simulation of Wet Scrubbers for Flue Gas Desulfurization

Authors: Anders Schou Simonsen, Kim Sorensen, Thomas Condra

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Wet scrubbers are used for flue gas desulfurization by injecting water directly into the flue gas stream from a set of sprayers. The water droplets will flow freely inside the scrubber, and flow down along the scrubber walls as a thin wall film while reacting with the gas phase to remove SO₂. This complex multiphase phenomenon can be divided into three main contributions: the continuous gas phase, the liquid droplet phase, and the liquid wall film phase. This study proposes a complete model, where all three main contributions are taken into account and resolved using OpenFOAM for the continuous gas phase, and MATLAB for the liquid droplet and wall film phases. The 3D continuous gas phase is composed of five species: CO₂, H₂O, O₂, SO₂, and N₂, which are resolved along with momentum, energy, and turbulence. Source terms are present for four species, energy and momentum, which are affecting the steady-state solution. The liquid droplet phase experiences breakup, collisions, dynamics, internal chemistry, evaporation and condensation, species mass transfer, energy transfer and wall film interactions. Numerous sub-models have been implemented and coupled to realise the above-mentioned phenomena. The liquid wall film experiences impingement, acceleration, atomization, separation, internal chemistry, evaporation and condensation, species mass transfer, and energy transfer, which have all been resolved using numerous sub-models as well. The continuous gas phase has been coupled with the liquid phases using source terms by an approach, where the two software packages are couples using a link-structure. The complete CFD model has been verified using 16 experimental tests from an existing scrubber installation, where a gradient-based pattern search optimization algorithm has been used to tune numerous model parameters to match the experimental results. The CFD model needed to be fast for evaluation in order to apply this optimization routine, where approximately 1000 simulations were needed. The results show that the complex multiphase phenomena governing wet scrubbers can be resolved in a single model. The optimization routine was able to tune the model to accurately predict the performance of an existing installation. Furthermore, the study shows that a coupling between OpenFOAM and MATLAB is realizable, where the data and source term exchange increases the computational requirements by approximately 5%. This allows for exploiting the benefits of both software programs.

Keywords: desulfurization, discrete phase, scrubber, wall film

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4176 The Effect of the Archeological and Architectural Nature of the Cities on the Design of Public Transportation Vehicles

Authors: Mohamed Moheyeldin Mahmoud

Abstract:

Various Islamic, Coptic and Jewish archeological places are located in many Egyptian neighborhoods such as Alsayeda zainab, Aldarb Alahmar, Algammaleya and many other in which they are daily exposed to a great traffic intensity causing vibrations. Vibrations could be stated as one of the most important challenges that face the archeological buildings and threaten their survival. The impact of vibrations varies according to the nature of the soil, nature and building conditions, how far the source of vibration is and the period of exposure. Traffic vibrations could be also stated as one of the most common types of vibrations having the greatest impact on buildings and archaeological installations. These vibrations result from the way that the vehicles act with different types of roads which vary according to the shape, nature, and type of obstacles. Other elements concerning the vehicle itself such as speed, weight, and load have a direct impact on the vibrations resulting from the vehicle movement that couldn't be neglected. The research aims to determine some of the requirements that must be observed when designing the public means of transport operating in the archaeological areas, in order to preserve the archaeological nature of the place. The research concludes that light weight slow motion vehicles should be used (25-50 km/h at maximum) having a multi-leaf steel spring suspension system instead of having an air-bag one should be used in order to reduce generated vibrations that could destroy the archeological buildings. Isolation layers could be used in the engine chamber in order to reduce the resulting noise causing vibrations. Electrically operated engines that use solar photovoltaic cells as a source of electricity could be used instead of gas ones in order to reduce the resulting engine noise.

Keywords: archeological, design, isolation layers, suspension, vibrations

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4175 Ecological-Economics Evaluation of Water Treatment Systems

Authors: Hwasuk Jung, Seoi Lee, Dongchoon Ryou, Pyungjong Yoo, Seokmo Lee

Abstract:

The Nakdong River being used as drinking water sources for Pusan metropolitan city has the vulnerability of water management due to the fact that industrial areas are located in the upper Nakdong River. Most citizens of Busan think that the water quality of Nakdong River is not good, so they boil or use home filter to drink tap water, which causes unnecessary individual costs to Busan citizens. We need to diversify water intake to reduce the cost and to change the weak water source. Under this background, this study was carried out for the environmental accounting of Namgang dam water treatment system compared to Nakdong River water treatment system by using emergy analysis method to help making reasonable decision. Emergy analysis method evaluates quantitatively both natural environment and human economic activities as an equal unit of measure. The emergy transformity of Namgang dam’s water was 1.16 times larger than that of Nakdong River’s water. Namgang Dam’s water shows larger emergy transformity than that of Nakdong River’s water due to its good water quality. The emergy used in making 1 m3 tap water from Namgang dam water treatment system was 1.26 times larger than that of Nakdong River water treatment system. Namgang dam water treatment system shows larger emergy input than that of Nakdong river water treatment system due to its construction cost of new pipeline for intaking Namgang daw water. If the Won used in making 1 m3 tap water from Nakdong river water treatment system is 1, Namgang dam water treatment system used 1.66. If the Em-won used in making 1 m3 tap water from Nakdong river water treatment system is 1, Namgang dam water treatment system used 1.26. The cost-benefit ratio of Em-won was smaller than that of Won. When we use emergy analysis, which considers the benefit of a natural environment such as good water quality of Namgang dam, Namgang dam water treatment system could be a good alternative for diversifying intake source.

Keywords: emergy, emergy transformity, Em-won, water treatment system

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4174 Synthesis of Nickel-Platinum Composite Nanoparticles and Silica-Coating of Them

Authors: Masato Yanase, Noriko Yamauchi, Shohei Tada, Yoshio Kobayashi

Abstract:

Nickel (Ni) and Ni-containing nanoparticles are promising materials due to their unique magnetic properties. In a preliminary experiment, aggregates of such nanoparticles formed after they were synthesized. Since the nanoparticle aggregation may deteriorate their unique properties, a method to suppress the nanoparticle aggregation has been required. In the present work, compositing with nickel (Ni) and platinum (Pt) and silica-coating of them were examined for suppression. Ni-Pt nanoparticles were synthesized in water exposed to air, in which nickel (II) acetate tetrahydrate, hexachloroplatinate (IV) hexahydrate, and sodium borohydride were used as a Ni source, a Pt source, and a reducing reagent, respectively. Polyvinylpyrrolidone, poly (sodium 4-styrene sulfonate), and citric acid were used as the stabilizers. Silica-coating of Ni-Pt nanoparticles was performed by adding tetraethylorthosilicate(TEOS)/ethanol solution to the Ni-Pt nanoparticle colloidal solution (Ni-Pt/SiO₂). The morphology of Ni-Pt nanoparticles was dependent on the reaction time and the species of stabilizer. The Ni-Pt/SiO₂ nanoparticles were composed of Ni-Pt nanoparticles as core and SiO₂ as shell, and their morphology depended on the TEOS concentrations. Furthermore, the Ni-Pt/SiO₂ nanoparticles were more dispersed compared to uncoated Ni-Pt nanoparticles. This suggested that the silica-coating had an effect on controlling the aggregation. The liquid-phase synthesis process involving the sol-gel method used in this study is advantageous for achieving monodispersion of particles and high-purity of materials. If the challenges of optimizing reaction conditions to achieve them during scale-up can be addressed, the proposed method holds great potential for large-scale production of particles in applications such as magnetic storage devices and biomedical imaging.

Keywords: metal, composite, nickel, platinum, nanoparticle, silica-coating

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4173 Phytochemical Constituents and Bioactive Properties of Glinus oppositifolius (L.) Aug. DC. against Bacterial Pathogens

Authors: Juliana Janet R. Martin-Puzon, Demetrio L. Valle, Windell L. Rivera

Abstract:

This study aimed to determine the presence of bioactive phytochemical constituents and evaluate the in vitro antibacterial activities of Glinus oppositifolius or carpet weed, a plant valued for its use in traditional medicine and as a vegetable. The leaves, stems, and roots were extracted using chloroform, ethanol, and methanol. Phytochemical screening revealed that the entire G. oppositifolius plant, i.e. roots, stems, and leaves, is a rich source of alkaloids, flavonoids, glycosides, saponins, sterols, tannins, and triterpenes. The antibacterial activity of the leaf and stem extracts were evaluated through disc diffusion, minimum inhibitory concentration, and bactericidal concentration assays against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), extended spectrum β-lactamase-producing (ESβL+), carbapenem-resistant Enterobacteriaceae (CRE), and metallo-β-lactamase-producing (MβL+) Pseudomonas aeruginosa and Acinetobacter baumannii. The leaf extracts revealed antibacterial activities, inhibiting the growth of non-resistant and multidrug-resistant (MDR) strains of the Gram-negative bacteria E. coli, P. aeruginosa, and A. baumanii. In conclusion, the various biological activities of G. oppositifolius, including its antibacterial activity, are due to the presence of diverse bioactive secondary metabolites. The presence of phytochemical compounds in G. oppositifolius is scientific evidence on its use for treatment of many ailments. Thus, the results demonstrate the great potential of the plant as a new, alternative source of antimicrobials and other components with therapeutic value.

Keywords: antibacterial, Glinus oppositifolius, multidrug-resistant, secondary metabolites

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4172 Nagami Kumkuat: A Source of Antiviral and Antimicrobial Bioactive Compounds

Authors: Howaida I. Abd-Alla, Nagwa M. M. Shalaby

Abstract:

The fruit rind of Fortunella margarita (Nagami Kumkuat) was investigated for its chemical constituents. Thirteen metabolites were obtained and classified into, a sterol; β-sitosterol (1) and twelve phenolic compounds, three coumarins; xanthotoxin (2), isopimpinellin (3), umbelliferone (4), nine flavonoids of O-glycosides of flavone; apigenin-7-O-β-D-glucopyranoside (5), apigenin-7-O-rhamnoglucoside (rhoifolin) (6), C-glycosides; vitexin (7), vicenin II (8), and the methoxylated; 6-methoxyapigenin-7-methyl ether (9) and tangeretin (10) as well as flavanones class; naringenin (11), liquiritigenin (12), hesperdin (hesperetin-7-rhamnoglucoside) (13). All compounds were identified for the first time in F. margarita except compound (8). The major glycosides 5, 6, and 13 and total crude extract showed potential antiviral activity against live Newcastle disease virus vaccine strains (Komarov and LaSota) and live infectious bursitis viruses vaccine strain D78 replication in VERO cell cultures and on specific pathogen-free embryonated chicken eggs. Antiviral inhibitory concentration fifty (IC50), cytotoxic concentration fifty (CC50), and therapeutic index (TI) were calculated. In addition, the extract and compounds 7 and 13 showed marked antimicrobial activity against different strains of fungi, Gram-positive and negative bacteria, including some foodborne pathogens of animal origin, caused human disease. These results suggested that the extract of F. margarita may be considered potentially useful as a source of natural antiviral and antimicrobial agents. It can be used as an ingredient for functional food and/or pharmaceuticals.

Keywords: antimicrobial, antiviral, Fortunella margarita, Nagami Kumkuat, phenolic secondary metabolites

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4171 NOx Abatement by CO with the Use of Grain Catalysts with Active Coating Made of Transition Metal (Cu, Mn, Nb) Oxides Prepared by Electroless Chemical Deposition Method

Authors: Davyd Urbanas, Pranas Baltrenas

Abstract:

It is well-known that, despite the constant increase of alternative energy sources usage, today combustible fuels are still widely used in power engineering. As a result of fuel combustion, significant amounts of nitrogen oxides (NOx) and carbon monoxide (CO is a product of incomplete combustion) are supplied to the atmosphere. Also, these pollutants are formed in industry (chemical production, refining, and metal production). In this work, the investigation of nitrogen oxides CO-selective catalytic reduction using new grain load-type catalysts was carried out. The catalysts containing the substrate and a thin active coating made of transition metal (Mn, Cu, and Nb) oxides were prepared with the use of electroless chemical deposition method. Chemical composition, chemical state, and morphology of the formed active coating were investigated using ICP-OES, EDX, SEM, and XPS techniques. The obtained results revealed that the prepared catalysts (Cu-Mn-oxide and Cu-Mn-Nb-oxide) have rough and developed surface and can be successfully used for the flue gas catalytic purification. The significant advantage of prepared catalysts is their suitability from technological application point of view, which differs this work from others dedicated to gas purification by SCR.

Keywords: flue gas, nitrogen oxides, selective catalytic reduction, transition metal oxides

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4170 The Impact of Employee's Perception of Corporate Social Responsibility on Job Satisfaction: Corporate Sector of Pakistan

Authors: Binish Ahmed

Abstract:

Corporate Social Responsibility (CSR) is regarded as voluntary behaviors that contribute to the social welfare based on the concept of sustainable development. The corporations should not only stress on their economic and business outcomes but also pay attention to their effect on the society and environment. It could attract investors and customers, as well as maintain a positive interaction with the government. In spite of the broad diffusion, and its potential significance to employees' perspective, CSR is now examined and has built-in Organizational Behavior (OB), and Human Resource Management (HRM) look into the broad structure of relationship between employees' perspective, work attitudes and behavior to improve the research on CSR. The purpose of this research is to investigate the impact of employees’ perception of CSR on work attitudes and behaviors of employees. A conceptual framework is proposed, based on the literature and practices. The research would conduct the primary data survey of convenient sampling from the employees and managers-using detailed questionnaire- to address the following questions. The survey of 180 respondents of age greater than 20 having at least six-month experience from companies based in Karachi are source of data. The application of professional empirical models for data analysis and interpretation are source to draw the conclusion. 1. What are the dynamics of CSR in an organization? Why is it important to have a CSR department? What sort of business approach are CSR activities practiced? Do CSR activities improve the quality of life of workplace? And, how it linked with welfare of society? 2. How the positive job attitude and behavior does encourage the employees about the perception of CSR? How is it linked with the job satisfaction? What is the relationship between employees’ perception of CSR and job satisfaction?

Keywords: corporate social responsibility, job satisfaction, organizational commitment, work behaviors

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4169 Constriction of Economic News over Business and Financial News: Analysis of the Change in Indian Business-Papers over the Past Three Decades

Authors: Disha Batra

Abstract:

With the advent of economic reforms in India in 1992, economic journalism in India has undergone a sea change along with the rise in the Indian economy. Squeezing out of economic news stories (economy-in-general) over business (individual corporate stories) and financial (financial and equity markets) news stories have been done and are still underway. The objective of the study is to explore how economic journalism – news stories about macroeconomic issues or economy-in-general has changed over the past three decades with the emergence of LPG (Liberalisation, Privatisation, and Globalisation) policies in India. The purpose of the study is to examine to what extent business and financial news are constricting economic news which is done by analysing news stories and content of business papers. The study is based on the content analyses of the top three Indian business dailies as per IRS (Indian Readership Survey) 2017. The parametric analysis of the different parameters (source of information, sub-topic, a dominant source in economic news, layout and framing, etc.) has been done in order to come across with the distinct adaptations and modifications by these dailies. The paper significantly dwells upon the thematic analysis of these newspapers in order to explore and find out the coverage given to various sub-themes of EBF (economic, business, and financial) journalism. The study revealed that stories concerning broader issues about the economy which are likely to be of public concern had been dropped. The paper further indicates an upward trend for the stories concerning individual corporate, equity, and financial markets. Findings of the study raise concern over the indicated disparity between economic and business news stories which may further limit the information that people need in order to make well-versed decisions.

Keywords: business-papers, business news, economic news, financial news

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4168 Sources of Precipitation and Hydrograph Components of the Sutri Dhaka Glacier, Western Himalaya

Authors: Ajit Singh, Waliur Rahaman, Parmanand Sharma, Laluraj C. M., Lavkush Patel, Bhanu Pratap, Vinay Kumar Gaddam, Meloth Thamban

Abstract:

The Himalayan glaciers are the potential source of perennial water supply to Asia’s major river systems like the Ganga, Brahmaputra and the Indus. In order to improve our understanding about the source of precipitation and hydrograph components in the interior Himalayan glaciers, it is important to decipher the sources of moisture and their contribution to the glaciers in this river system. In doing so, we conducted an extensive pilot study in a Sutri Dhaka glacier, western Himalaya during 2014-15. To determine the moisture sources, rain, surface snow, ice, and stream meltwater samples were collected and analyzed for stable oxygen (δ¹⁸O) and hydrogen (δD) isotopes. A two-component hydrograph separation was performed for the glacier stream using these isotopes assuming the contribution of rain, groundwater and spring water contribution is negligible based on field studies and available literature. To validate the results obtained from hydrograph separation using above method, snow and ice melt ablation were measured using a network of bamboo stakes and snow pits. The δ¹⁸O and δD in rain samples range from -5.3% to -20.8% and -31.7% to -148.4% respectively. It is noteworthy to observe that the rain samples showed enriched values in the early season (July-August) and progressively get depleted at the end of the season (September). This could be due to the ‘amount effect’. Similarly, old snow samples have shown enriched isotopic values compared to fresh snow. This could because of the sublimation processes operating over the old surface snow. The δ¹⁸O and δD values in glacier ice samples range from -11.6% to -15.7% and -31.7% to -148.4%, whereas in a Sutri Dhaka meltwater stream, it ranges from -12.7% to -16.2% and -82.9% to -112.7% respectively. The mean deuterium excess (d-excess) value in all collected samples exceeds more than 16% which suggests the predominant moisture source of precipitation is from the Western Disturbances. Our detailed estimates of the hydrograph separation of Sutri Dhaka meltwater using isotope hydrograph separation and glaciological field methods agree within their uncertainty; stream meltwater budget is dominated by glaciers ice melt over snowmelt. The present study provides insights into the sources of moisture, controlling mechanism of the isotopic characteristics of Sutri Dhaka glacier water and helps in understanding the snow and ice melt components in Chandra basin, Western Himalaya.

Keywords: D-excess, hydrograph separation, Sutri Dhaka, stable water isotope, western Himalaya

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4167 Study of Oxidative Stability, Cold Flow Properties and Iodine Value of Macauba Biodiesel Blends

Authors: Acacia A. Salomão, Willian L. Gomes da Silva, Gustavo G. Shimamoto, Matthieu Tubino

Abstract:

Biodiesel physical and chemical properties depend on the raw material composition used in its synthesis. Saturated fatty acid esters confer high oxidative stability, while unsaturated fatty acid esters improve the cold flow properties. In this study, an alternative vegetal source - the macauba kernel oil - was used in the biodiesel synthesis instead of conventional sources. Macauba can be collected from native palm trees and is found in several regions in Brazil. Its oil is a promising source when compared to several other oils commonly obtained from food products, such as soybean, corn or canola oil, due to its specific characteristics. However, the usage of biodiesel made from macauba oil alone is not recommended due to the difficulty of producing macauba in large quantities. For this reason, this project proposes the usage of blends of the macauba oil with conventional oils. These blends were prepared by mixing the macauba biodiesel with biodiesels obtained from soybean, corn, and from residual frying oil, in the following proportions: 20:80, 50:50 e 80:20 (w/w). Three parameters were evaluated, using the standard methods, in order to check the quality of the produced biofuel and its blends: oxidative stability, cold filter plugging point (CFPP), and iodine value. The induction period (IP) expresses the oxidative stability of the biodiesel, the CFPP expresses the lowest temperature in which the biodiesel flows through a filter without plugging the system and the iodine value is a measure of the number of double bonds in a sample. The biodiesels obtained from soybean, residual frying oil and corn presented iodine values higher than 110 g/100 g, low oxidative stability and low CFPP. The IP values obtained from these biodiesels were lower than 8 h, which is below the recommended standard value. On the other hand, the CFPP value was found within the allowed limit (5 ºC is the maximum). Regarding the macauba biodiesel, a low iodine value was observed (31.6 g/100 g), which indicates the presence of high content of saturated fatty acid esters. The presence of saturated fatty acid esters should imply in a high oxidative stability (which was found accordingly, with IP = 64 h), and high CFPP, but curiously the latter was not observed (-3 ºC). This behavior can be explained by looking at the size of the carbon chains, as 65% of this biodiesel is composed by short chain saturated fatty acid esters (less than 14 carbons). The high oxidative stability and the low CFPP of macauba biodiesel are what make this biofuel a promising source. The soybean, corn and residual frying oil biodiesels also have low CFPP, but low oxidative stability. Therefore the blends proposed in this work, if compared to the common biodiesels, maintain the flow properties but present enhanced oxidative stability.

Keywords: biodiesel, blends, macauba kernel oil, stability oxidative

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4166 Synthesis of Flavonoid Derivatives Precursors of Active Pharmaceutical Ingredients by Mechanical Chemistry

Authors: Imen Abid, Rachel Calvet, Michel Baltas

Abstract:

Flavonoids are secondary metabolites that belong to a polyphenolic class, present in fruits and vegetables, playing a significant role in biological systems. The structural variations of these flavonoids are associated with many biological and pharmacological activities (antioxidant, anti-inflammatory, anticancer, antibacterial, antifungal, antiviral, and antimalarial). Given their importance in plants and health-promoting roles in humans, significant efforts have been devoted towards their isolation of flavonoids and chemical elaboration (organic synthesis). But with the increasing public concern over environmental degradation and future resources, it is of great importance for chemists to come up with different approaches, less hazardous to human health and the environment. Being employed in large amounts, the solvents used in organic synthesis are high on the list of environmental pollutants. To overcome these problems, our approach is to develop unconventional processes involving solvent-free conditions. The application of mechanical forces to solvent-free or solvent-less reaction mixtures through the use of ball mills offers many advantages over traditional solvent-based strategies. It is one of the unconventional activation methods, which makes it possible to overcome the use of solvents, in the context of green chemistry and more respectful of the environment.

Keywords: organic synthesis, green chemistry, mecanochemistry, pharmaceutical molecules

Procedia PDF Downloads 76