Search results for: random temperature

Authors: Fatemeh Soltani, Simindokht Shirvani Arani, Ali Bahrami Samani, Mahdi Sadeghi, Kamal Yavari

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Cerium-141 [T1/2 = 32.501 days, Eβ (max) = 0.580 (29.8%) and 0.435(70.2%) MeV, Eγ=145.44 (48.2%) keV] possesses radionuclidic properties suitable for use in palliative therapy of bone metastases. 141Ce also has gamma energy of 145.44 keV, which resembles that of 99mTc. Therefore, the energy window is adjustable on the Tc-99m energy because of imaging studies. 141Ce can be produced through a relatively easy route that involves thermal neutron bombardment on natural CeO2 in medium flux research reactors (4–5×1013 neutrons/cm2•s). The requirement for an enriched target does not arise. Ethylenediamine tetramethylene phosphonic acid (EDTMP) was synthesized and radiolabeled with 141Ce. Complexation parameters were optimized to achieve maximum yields (>99%). The radiochemical purity of 141Ce-EDTMP was evaluated by radio-thin layer chromatography. The stability of the prepared formulation was monitored for one week at room temperature, and results showed that the preparation was stable during this period (>99%). Biodistribution studies of the complexes carried out in wild-type rats exhibited significant bone uptake with rapid clearance from blood. The properties of produced 141Ce-EDTMP suggest applying a new efficient bone pain palliative therapeutic agent to overcome metastatic bone pains.

Keywords: bone pain palliative, cerium-141, EDTMP, radiopharmaceutical

Procedia PDF Downloads 487

Authors: N. P. G. N. Chandrasekara, R. M. Pashley

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Ion exchange (IEX) resins are commonly available as cationic or anionic resins but not as polyampholytic resins. This is probably because sequential acid and base washing cannot produce complete regeneration of polyampholytic resins with chemically attached anionic and cationic groups in close proximity. The ‘Sirotherm’ process, developed by the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Melbourne, Australia was originally based on the use of a physical mixture of weakly basic (WB) and weakly acidic (WA) ion-exchange resin beads. These resins were regenerated thermally and they were capable of removing salts from an aqueous solution at higher temperatures compared to the salt sorbed at ambient temperatures with a significant reduction of the sorption capacity with increasing temperature. A new process for the efficient regeneration of mixed bead resins using ammonium bicarbonate with heat was studied recently and this chemical/thermal regeneration technique has the capability for completely regenerating polyampholytic resins. Even so, the low IEX capacities of polyampholytic resins restrict their commercial applications. Recently, we have established another novel process for increasing the IEX capacity of a typical polyampholytic resin. In this paper we will discuss the chemical/thermal regeneration of a polyampholytic (WA/WB) resin and a novel process for enhancing its ion exchange capacity, by increasing its internal pore area. We also show how effective this method is for completely recycled regeneration, with the potential of substantially reducing chemical waste.

Keywords: capacity, ion exchange, polyampholytic resin, regeneration

Procedia PDF Downloads 375

Authors: Betina Luiza Koop, Lenilton Santos Soares, Karina Cesca, Germán Ayala Valencia, Alcilene Rodrigues Monteiro

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Active and smart food packaging has been studied to control and extend the food shelf-life. However, active compounds such as anthocyanins (ACNs) are unstable to high temperature, light, and pH changes. Several alternatives to stabilize and protect the anthocyanins have been researched, such as adsorption on nanoclays. Thus, this work aimed to stabilize anthocyanin extracted from jambolan fruit (Syzygium cumini), a noncommercial fruit, to development of food package sensors. The anthocyanin extract from jambolan pulp was concentrated by ultrafiltration and adsorbed on montmorillonite. The final biohybrid material was characterized by pH and color. Anthocyanins were adsorbed on nanoclay at pH 1.5, 2.5, and 3.5 and temperatures of 10 and 20 °C. The highest adsorption values were obtained at low pH at high temperatures. The color and antioxidant activity of the biohybrid was maintained for 60 days. A test of the color stability at pH from 1 to 13, simulating spoiled food using ammonia vapor, was performed. At pH from 1 to 5, the ACNs pink color was maintained, indicating that the flavylium cation form was preserved. At pH 13, the biohybrid presented yellow color due to the ACN oxidation. These results showed that the biohybrid material developed has potential application as a sensor to indicate the freshness of meat products.

Keywords: anthocyanin, biohybrid, food, smart packaging

Procedia PDF Downloads 67

Authors: Sophie Oakes-Rogers, Di Bailey, Karen Slade

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Female offenders are a uniquely vulnerable group, who are at high risk of suicide. Whilst the prevention of self-harm and suicide remains a key global priority, we need to better understand the relationship between these challenging behaviours that constitute a pressing problem, particularly in environments designed to prioritise safety and security. Method choice is unlikely to be random, and is instead influenced by a range of cultural, social, psychological and environmental factors, which change over time and between countries. A key aspect of self-harm and suicide in women receiving forensic care is the lack of free access to methods. At a time where self-harm and suicide rates continue to rise internationally, understanding the role of these influencing factors and the impact of current suicide prevention strategies on the use of near-lethal methods is crucial. This poster presentation will present findings from 25 interviews and 3 focus groups, which enlisted a Participatory Action Research approach to explore the differences between self-harming and suicidal behavior. A key element of this research was using the lived experiences of women receiving forensic care from one forensic pathway in the UK, and the staffs who care for them, to discuss the role of near-lethal self-harm (NLSH). The findings and suggestions from the lived accounts of the women and staff will inform a draft assessment tool, which better assesses the risk of suicide based on the lethality of methods. This tool will be the first of its kind, which specifically captures the needs of women receiving forensic services. Preliminary findings indicate women engage in NLSH for two key reasons and is determined by their history of self-harm. Women who have a history of superficial non-life threatening self-harm appear to engage in NLSH in response to a significant life event such as family bereavement or sentencing. For these women, suicide appears to be a realistic option to overcome their distress. This, however, differs from women who appear to have a lifetime history of NLSH, who engage in such behavior in a bid to overcome the grief and shame associated with historical abuse. NLSH in these women reflects a lifetime of suicidality and indicates they pose the greatest risk of completed suicide. Findings also indicate differences in method selection between forensic provisions. Restriction of means appears to play a role in method selection, and findings suggest it causes method substitution. Implications will be discussed relating to the screening of female forensic patients and improvements to the current suicide prevention strategies.

Keywords: forensic mental health, method substitution, restriction of means, suicide

Procedia PDF Downloads 173

Authors: Feng-Tsai Weng, Rick Wang, Yan-Cong Liao

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Passivation is a kind of surface treatment for material to reinforce the corrosion resistance specially the stainless alloy. Passive film, is to getting more potential compared to their status before passivation. An oxidation film can be formed on the surface of stainless steel, which has a strong corrosion resistance ability after passivation treatment. In this research, a new passivation technology is proposed for a special stainless alloy which contains a 12-14% Chromium. This method includes the A-A-A (alkaline-acid-alkaline) process basically, which was developed by Carpenter that can neutralize trapped acid. Besides, a corrosion resistant coating layer was obtained by immersing the parts in a water bath of mineral oil at high temperature. Salt spray test ASTM B368 was conducted to investigated performance of corrosion resistant of the passivated stainless steel alloy parts. Results show much better corrosion resistant that followed a coating process after A-A-A Passivation process, than only using A-A-A process. The passivation time is with more than 380 hours of salt spray test ASTM B368, which is equal to 3000 hours of Salt spray test ASTM B117. Proposed passivation method of stainless steel can be completed in about 3 hours.

Keywords: passivation, alkaline-acid-alkaline, stainless steel, salt spray test

Procedia PDF Downloads 358

Authors: Dandi Riswanto, Mahendra Wahyu Eka Pradana, Hutomo Abdurrohman

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The dairy farm has strategic roles in meeting the demand of foods. Sleman Regency is a central dairy production in Daerah Istimewa Yogyakarta. Sleman district has a population of 3954 heads dairy cattle with an environmental temperature of 22 to 35 degrees Celsius and humidity 74 to 87% which makes a good location for a dairy cattle farm. The dairy cattle that are kept by the majority of the Friesian Holstein Crossbreed are predominantly reared by conventional management. Sleman Regency accounts for 7.3% of national milk production. Factors influencing include genetic, environmental, and management. The purpose of this research was to determine the effect of Good Dairy Farming Practices (GDFP) application on milk production in Sleman Regency. The data collection was conducted in January 2017 until May 2017 using survey and interviews methods at 5 locations of dairy farms selected randomly. Data were analyzed with the chi-square test. The result of this research showed that GDFP point was management 1,47 points (less good). The result showed that Good Dairy Farming Practices (GDFP) has a positive effect on milk production.

Keywords: dairy cattle, GDFP, milk production, Sleman regency

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Authors: U.N. Emiri, E. Moroyei

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Mycoflora associated with the seed rot disease of Mucuna sloanei and their effects on nutrient and phytochemical composition of the seeds were investigated. The fungal pathogens implicated in the seed rot disease were Rhizopus stolonifer, Aspergillus flavus, Aspergillus niger, and Fusarium oxysporum. The fungal isolates were aseptically inoculated into healthy M. Sloanei seeds and incubated for 7 days at room temperature of 25 ± 30c. The results of the proximate and mineral analysis in mg/100g of fungal infected and non-infected (control) seeds that were carried out revealed that there was an increase in Moisture and Carbohydrate content of the fungal infected seeds relative to the non-infected seeds (control). However, there was a decrease in Ash, Fibre, Lipid, and Protein content of the fungal infected seeds relative to the non-infected (control). It was observed that moisture had increased from 10.50 ± 0.16 in the non-infected seeds to 17.60 ± 0.20 in the infected samples and Carbohydrate content had also increased from 49.6 ± 0.25 in the non-infected to 52.50 ± 0.29 in the infected seeds. The following parameters decreased in the infected than in the non-infected seeds. They include Ash 2.60 ± 0.12, Crude fibre 1.9 ± 0.08, Lipid 6.50 ± 0.16, and Protein content 18.50 ± 0.06. Similarly, Calcium 2.50 ± 0.12, Phosphorus 1.80 + 0.12 and Potassium 1.80 + 0.09 increased in the infected than in the non-infected seed, while iron 0.20 ± 0.05, Sodium 0.02 ± 0.01 and Magnesium 0.06 ± 0.02 decreased in the infected seeds. All phytochemical contents analyzed increased in the infected seeds viz Tannim 0.50 ± 0.12, Oxalate 1.60 ± 0.05, Hydrogen cyanide 1.82 ± 0.06, and Saponin 2.50+0.28. However, the nutrient compositions and Phytochemical between the infected and non-infected seeds are not significantly different (p > 0.05).

Keywords: Mycoflora, mucuna sloanei, seeds, phytochemical, nutrient composition

Procedia PDF Downloads 151

Authors: Hana Gebremariam Liliso

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This study investigates the factors contributing to the deterioration of thick asphalt pavements, such as rutting and cracking. We focus on the combined influence of traffic loads and pavement structure. This study uses a three-dimensional finite element model with a Mohr-Coulomb failure criterion to analyze the stress levels near the pavement's surface under realistic conditions. Our model considers various factors, including tire-pavement contact stresses, asphalt properties, moving loads, and dynamic analysis. This research suggests that cracking tends to occur between dual tires. Some key discoveries include the risk of cracking increases as temperatures rise; surface cracking at high temperatures is associated with distortional deformation; using a uniform contact stress distribution underestimates the risk of failure compared to realistic three-dimensional tire contact stress, particularly at high temperatures; the risk of failure is higher near the surface when there is a negative temperature gradient in the asphalt layer; and debonding beneath the surface layer leads to increased shear stress and premature failure around the interface.

Keywords: asphalt pavement, surface failure, 3d finite element model, multiaxial stress states, Mohr-Coulomb failure criterion

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Authors: Aisami A., Z. A. Adamu, Lawan Bulama

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Due to growing issues of crude oil pollution in both marine and terrestrial environments, Billions to Trillions of US Dollars were spent over the years for the treatment of this spill. There is an urgent need for effective bioremediation strategies. This current study focuses on the isolation and characterization of a crude oil-degrading bacterium from hydrocarbon-contaminated soil samples. Soil samples were collected from an oil spill site and subjected to enrichment culture techniques in a mineral salt medium supplemented with crude oil as the singular carbon source. The isolates were screened for their crude oil-degrading capabilities using gravimetric analysis. The most efficient isolation was identified through 16S rRNA gene sequencing. Cultural and physical conditions such pH, temperature salinity and crude oil concentrations were optimized. The isolates showed significant crude oil degradation efficiency, reducing oil concentration (2.5%) by 75% within 15 days of incubation. The strain was identified as Providencia sp. through molecular characterization, the sequence was deposited at the NCBI Genbank with accession number MN880494. The bacterium exhibited optimal growth at 32.5°C, pH 7.0 to 7.5, and in the presence of 1.5% (w/v) NaCl. The isolated Providencia sp. shows encouraging potential for bioremediation of crude oil-contaminated environments. This study successfully isolated and characterized a crude oil-degrading Providencia sp., highlighting its potential in bioremediation.

Keywords: crude oil degradation, providencia sp., bioremediation, hydrocarbon utilization, environmental pollution.

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Authors: Rym Taktak, Achwek Elghazel, Jamel Bouaziz

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In the present work, we explored the potential of tribological behavior of tricalcium phosphate-Fluorapatite (β Tcp-Fap) bioceramic which has attracted considerable attention for orthopedics and dental applications. The approximate representatives Fap-βTcp were respectively [{13.26 wt%, 86.74 wt%} {19.9 wt%, 80.1 wt%},{ 26.52 wt%, 73.48 wt%}, {33.16 wt%, 66.84 wt%} and {40 wt%, 60 wt%}. The effects of Fluorapatite additives on friction and wear behavior were studied and discussed. The wear test was conducted using pion-disk tribometer at room temperature under dry condition using a constant sliding speed of 0,063 m/s, and three loads 3, 5 and 8 N. The wear rate and friction coefficient of β Tcp with different additive amounts were compared. An Alumina ball specimens were used as the pin and flat surface β Tcp-Fap specimens as the antagonist counterface. The results show a huge difference between the wear rate of β TCP samples and the other β TCP-Fap composites for all normal forces applied. This result shows the beneficial effect of fluorapatite on the tribological behavior of the β TCP. Moreover, we note that β Tcp-26% Fap specimens exhibit, under dry condition, the lower friction coefficient and the smaller wear rate than other biocomposites. Thereby, the friction and wear behavior is influenced by the addition of fluorapatite, the applied normal force, and the sliding velocity. To extend the understanding of the wear process, the surface topography of β Tcp-26% Fap specimens and the wear track obtained during the wear tests were studied using a surface profilometer, optical microscopy, and scanning electron microscopy.

Keywords: alumina, bioceramic, friction and wear test, tricalcium phosphate

Procedia PDF Downloads 231

Authors: Jiayue Guo, Lili You

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Background: Children and adolescent health are crucial for both personal well-being and the nation's future health landscape. Health Literacy (HL) is important in enabling adolescents to self-manage their health, a fundamental step towards health empowerment. However, there are limited tools for assessing HL among elementary and junior high school students. This study aims to construct and validate a test-based HL scale for Chinese students, offering a scientific reference for cross-cultural HL tool development. Methods: We conducted a cross-sectional online survey. Participants were recruited from a stratified cluster random sampling method, a total of 4189 Chinese in-school primary and secondary students. The development of the scale was completed by defining the concept of HL, establishing the item indicator system, screening items (7 health content dimensions), and evaluating reliability and validity. Delphi method expert consultation was used to screen items, the Rasch model was conducted for quality analysis, and Cronbach’s alpha coefficient was used to examine the internal consistency. Results: We developed four versions of the HL scale, each with a total score of 100, encompassing seven key health areas: hygiene, nutrition, physical activity, mental health, disease prevention, safety awareness, and digital health literacy. Each version measures four dimensions of health competencies: knowledge, skills, motivation, and behavior. After the second round of expert consultation, the average importance score of each item by experts is 4.5–5.0, and the coefficient of variation is 0.000–0.174. The knowledge and skills dimensions are judgment-based and multiple-choice questions, with the Rasch model confirming unidimensionality at a 5.7% residual variance. The behavioral and motivational dimensions, measured with scale-type items, demonstrated internal consistency via Cronbach's alpha and strong inter-item correlation with KMO values of 0.924 and 0.787, respectively. Bartlett's test of sphericity, with p-values <0.001, further substantiates the scale's reliability. Conclusions: The new test-based scale, designed to evaluate competencies within a multifaceted framework, aligns with current international adolescent literacy theories and China's health education policies, focusing not only on knowledge acquisition but also on the application of health-related thinking and behaviors. The scale can be used as a comprehensive tool for HL evaluation and a reference for other countries.

Keywords: adolescent health, Chinese, health literacy, rasch model, scale development

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Authors: Tamara Romero, Manuel Romero-Huelva, Jose V. Segarra, Jose Castro, Carlos Fernandez

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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 143

Authors: Ryoko Yoshida, Jyunpei Yoshida, Hua Fang Yu, Yasushi Sasaki, Tetsuya Nagasaka

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Phosphorous is an important element for agriculture and industry and is a non-renewable resource. Especially, yellow phosphorus is an essential material in advanced industrial technology, but phosphorus resources were not produced in Japan at all, and all depend on imports. It has been suggested, however, that the remaining accessible reserves of phosphate ore will be depleted within 50 years. Therefore, alternative resources for phosphate ore must be found. In this research, we have developed a process that enables the production of high-purity yellow phosphorus from domestic unused phosphorus resources such as steelmaking slags. The process consists of two parts: (1) the production of crude phosphoric acid from wastes such as steelmaking slag; (2) producing high-purity yellow phosphorus by low-temperature carbothermic reduction of phosphoric acid (H₃PO₄). The details of the carbothermic reduction of phosphoric acid are presented in this paper. Yellow phosphorus is commercially produced by carbothermic reduction of phosphate ore in an electric arc furnace at more than 1673K. In the newly developed system, gaseous P₄O₁₀ evaporated from H₃PO₄ is successfully reduced to yellow phosphorus by using carbon packed bed at less than 1273K. To meet the depletion of phosphate ore, the proposed process in this study to produce yellow phosphorus by carbothermic reduction of H₃PO₄ that are extracted from dephosphorization slags will be one of the effective and economical solutions.

Keywords: carbothermic reduction, phosphoric acid, dephosphorization slags, yellow phosphorus

Procedia PDF Downloads 116

Authors: Fatiha Atmani, Lamia Djellab, Nacera Yeddou Mezenner, Zohra Bensaadi

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Generally, bilge waters can be briefly defined as saline and greasy wastewaters. The oil and grease are mixed with the sea water, which affects many marine species. Bilge water is a complex mixture of various compounds such as solvents, surfactants, fuel, lubricating oils, and hydraulic oils. It is resulted mainly by the leakage from the machinery and fresh water washdowns,which are allowed to drain to the lowest inner part of the ship's hull. There are several physicochemical methods used for bilge water treatment such as biodegradation electrochemical and electro-coagulation/flotation.The research herein presented discusses adsorption as a method to treat bilge water and eggshells were studied as an adsorbent. The influence of operating parameters as contact time, temperature and adsorbent dose (0,2 - 2g/l) on the removal efficiency of Chemical oxygen demand, COD, and turbidity was analyzed. The bilge wastewater used for this study was supplied by Harbour Bouharoune. Chemical oxygen demand removal increased from 26.7% to 68.7% as the adsorbent dose increased from 0.2 to 2 g. The kinetics of adsorption by eggshells were fast, reaching 55 % of the total adsorption capacity in ten minutes (T= 20°C, pH =7.66, m=2g/L). It was found that the turbidity removal efficiency decreased and 95% were achieved at the end of 90 min reaction. The adsorption process was found to be effective for the purification of bilge water and pseudo-second-order kinetic model was fitted for COD removal.

Keywords: adsorption, bilge water, eggshells and kinetics, equilibrium and kinetics

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Authors: Kaustuvmani Patowary, Suresh Deka

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Oil pollution accidents, nowadays, have become a common phenomenon and have caused ecological and social disasters. Microorganisms with high oil-degrading performance are essential for bioremediation of petroleum hydrocarbon. In this investigation, an effective biosurfactant producer and hydrocarbon degrading bacterial strain, Pseudomonas sp.PG1 (identified by 16s rDNA sequencing) was isolated from hydrocarbon contaminated garage soil of Pathsala, Assam, India, using crude oil enrichment technique. The growth parameters such as pH and temperature were optimized for the strain and upto 81.8% degradation of total petroleum hydrocarbon (TPH) has been achieved after 5 weeks when grown in mineral salt media (MSM) containing 2% (w/v) crude oil as the carbon source. The biosurfactant production during the course of hydrocarbon degradation was monitored by surface tension measurement and emulsification activity. The produced biosurfactant had the ability to decrease the surface tension of MSM from 72 mN/m to 29.6 mN/m, with the critical micelle concentration (CMC)of 56 mg/L. The biosurfactant exhibited 100% emulsification activity on crude oil. FTIR spectroscopy and LCMS-MS analysis of the purified biosurfactant revealed that the biosurfactant is Rhamnolipidic in nature with several rhamnolipid congeners. Gas Chromatography-Mass spectroscopy (GC-MS) analysis clearly demonstrated that the strain PG1 efficiently degrade different hydrocarbon fractions of the crude oil. The study suggeststhat application of the biosurfactant producing strain PG1 as an appropriate candidate for bioremediation of crude oil contaminants.

Keywords: petroleum hydrocarbon, hydrocarbon contamination, bioremediation, biosurfactant, rhamnolipid

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Authors: Jerome Joshi

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The paper presents the modelling of financial markets using the Stochastic Pi Calculus model. The Stochastic Pi Calculus model is mainly used for biological applications; however, the feature of this model promotes its use in financial markets, more prominently in high frequency trading. The trading system can be broadly classified into exchange, market makers or intermediary traders and fundamental traders. The exchange is where the action of the trade is executed, and the two types of traders act as market participants in the exchange. High frequency trading, with its complex networks and numerous market participants (intermediary and fundamental traders) poses a difficulty while modelling. It involves the participants to seek the advantage of complex trading algorithms and high execution speeds to carry out large volumes of trades. To earn profits from each trade, the trader must be at the top of the order book quite frequently by executing or processing multiple trades simultaneously. This would require highly automated systems as well as the right sentiment to outperform other traders. However, always being at the top of the book is also not best for the trader, since it was the reason for the outbreak of the ‘Hot – Potato Effect,’ which in turn demands for a better and more efficient model. The characteristics of the model should be such that it should be flexible and have diverse applications. Therefore, a model which has its application in a similar field characterized by such difficulty should be chosen. It should also be flexible in its simulation so that it can be further extended and adapted for future research as well as be equipped with certain tools so that it can be perfectly used in the field of finance. In this case, the Stochastic Pi Calculus model seems to be an ideal fit for financial applications, owing to its expertise in the field of biology. It is an extension of the original Pi Calculus model and acts as a solution and an alternative to the previously flawed algorithm, provided the application of this model is further extended. This model would focus on solving the problem which led to the ‘Flash Crash’ which is the ‘Hot –Potato Effect.’ The model consists of small sub-systems, which can be integrated to form a large system. It is designed in way such that the behavior of ‘noise traders’ is considered as a random process or noise in the system. While modelling, to get a better understanding of the problem, a broader picture is taken into consideration with the trader, the system, and the market participants. The paper goes on to explain trading in exchanges, types of traders, high frequency trading, ‘Flash Crash,’ ‘Hot-Potato Effect,’ evaluation of orders and time delay in further detail. For the future, there is a need to focus on the calibration of the module so that they would interact perfectly with other modules. This model, with its application extended, would provide a basis for researchers for further research in the field of finance and computing.

Keywords: concurrent computing, high frequency trading, financial markets, stochastic pi calculus

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Authors: J. Fox, J. Randhawa, M. Chan, L. Campbell, A. Weakely, D. J. Harvey, S. Tomaszewski Farias

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Early identification of individuals at risk for conversion to dementia provides an opportunity for preventative treatment. Many older adults (30-60%) report specific subjective cognitive decline (SCD); however, previous research is inconsistent in terms of what types of complaints predict future cognitive decline. The purpose of this study is to identify which specific complaints from the Everyday Cognition Scales (ECog) scales, a measure of self-reported concerns for everyday abilities across six cognitive domains, are associated with: 1) conversion from a clinical diagnosis of normal to either MCI or dementia (categorical variable) and 2) progressive cognitive decline in memory and executive function (continuous variables). 415 cognitively normal older adults were monitored annually for an average of 5 years. Cox proportional hazards models were used to assess associations between self-reported ECog items and progression to impairment (MCI or dementia). A total of 114 individuals progressed to impairment; the mean time to progression was 4.9 years (SD=3.4 years, range=0.8-13.8). Follow-up models were run controlling for depression. A subset of individuals (n=352) underwent repeat cognitive assessments for an average of 5.3 years. For those individuals, mixed effects models with random intercepts and slopes were used to assess associations between ECog items and change in neuropsychological measures of episodic memory or executive function. Prior to controlling for depression, subjective concerns on five of the eight Everyday Memory items, three of the nine Everyday Language items, one of the seven Everyday Visuospatial items, two of the five Everyday Planning items, and one of the six Everyday Organization items were associated with subsequent diagnostic conversion (HR=1.25 to 1.59, p=0.003 to 0.03). However, after controlling for depression, only two specific complaints of remembering appointments, meetings, and engagements and understanding spoken directions and instructions were associated with subsequent diagnostic conversion. Episodic memory in individuals reporting no concern on ECog items did not significantly change over time (p>0.4). More complaints on seven of the eight Everyday Memory items, three of the nine Everyday Language items, and three of the seven Everyday Visuospatial items were associated with a decline in episodic memory (Interaction estimate=-0.055 to 0.001, p=0.003 to 0.04). Executive function in those reporting no concern on ECog items declined slightly (p <0.001 to 0.06). More complaints on three of the eight Everyday Memory items and three of the nine Everyday Language items were associated with a decline in executive function (Interaction estimate=-0.021 to -0.012, p=0.002 to 0.04). These findings suggest that specific complaints across several cognitive domains are associated with diagnostic conversion. Specific complaints in the domains of Everyday Memory and Language are associated with a decline in both episodic memory and executive function. Increased monitoring and treatment of individuals with these specific SCD may be warranted.

Keywords: alzheimer’s disease, dementia, memory complaints, mild cognitive impairment, risk factors, subjective cognitive decline

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Authors: B. Kriheli, E. Levner, T. C. E. Cheng, C. T. Ng

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During the last decades, research interest in planning, scheduling, and control of emergency response operations, especially people rescue and evacuation from the dangerous zone of marine accidents, has increased dramatically. Until the survivors (called ‘targets’) are found and saved, it may cause loss or damage whose extent depends on the location of the targets and the search duration. The problem is to efficiently search for and detect/rescue the targets as soon as possible with the help of intelligent mobile robots so as to maximize the number of saved people and/or minimize the search cost under restrictions on the amount of saved people within the allowable response time. We consider a special situation when the autonomous mobile robots (AMR), e.g., unmanned aerial vehicles and remote-controlled robo-ships have no operator on board as they are guided and completely controlled by on-board sensors and computer programs. We construct a mathematical model for the search process in an uncertain environment and provide a new fast algorithm for scheduling the activities of the autonomous robots during the search-and rescue missions after an accident at sea. We presume that in the unknown environments, the AMR’s search-and-rescue activity is subject to two types of error: (i) a 'false-negative' detection error where a target object is not discovered (‘overlooked') by the AMR’s sensors in spite that the AMR is in a close neighborhood of the latter and (ii) a 'false-positive' detection error, also known as ‘a false alarm’, in which a clean place or area is wrongly classified by the AMR’s sensors as a correct target. As the general resource-constrained discrete search problem is NP-hard, we restrict our study to finding local-optimal strategies. A specificity of the considered operational research problem in comparison with the traditional Kadane-De Groot-Stone search models is that in our model the probability of the successful search outcome depends not only on cost/time/probability parameters assigned to each individual location but, as well, on parameters characterizing the entire history of (unsuccessful) search before selecting any next location. We provide a fast approximation algorithm for finding the AMR route adopting a greedy search strategy in which, in each step, the on-board computer computes a current search effectiveness value for each location in the zone and sequentially searches for a location with the highest search effectiveness value. Extensive experiments with random and real-life data provide strong evidence in favor of the suggested operations research model and corresponding algorithm.

Keywords: disaster management, intelligent robots, scheduling algorithm, search-and-rescue at sea

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Authors: A. N. Fouda

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A novel well identified hexagonal graphene oxide (GO) nano-sheets were synthesized using modified Hummer method. Low temperature thermal reduction at 350°C in air ambient was performed. After thermal reduction, typical few layers of thermal reduced GO (TRGO) with dimension of few hundreds nanometers were observed using high resolution transmission electron microscopy (HRTEM). GO has a lot of structure models due to variation of the preparation process. Determining the atomic structure of GO is essential for a better understanding of its fundamental properties and for realization of the future technological applications. Structural characterization was identified by x-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR) measurements. A comparison between exper- imental and theoretical IR spectrum were done to confirm the match between experimentally and theoretically proposed GO structure. Partial overlap of the experimental IR spectrum with the theoretical IR was confirmed. The electrochemical properties of TRGO nano-sheets as electrode materials for supercapacitors were investigated by cyclic voltammetry and electrochemical impedance spectroscopy (EIS) measurements. An enhancement in supercapacitance after reduction was confirmed and the area of the CV curve for the TRGO electrode is larger than those for the GO electrode indicating higher specific capacitance which is promising in super-capacitor applications

Keywords: hexagonal graphene oxide, thermal reduction, cyclic voltammetry

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Authors: Clarinda V. Nhangumbe, Ercília Sousa

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Weather Derivatives are financial instruments used to cover non-catastrophic weather events and can be expressed in the form of standard or plain vanilla products, structured or exotics products. The underlying asset, in this case, is the weather index, such as temperature, rainfall, humidity, wind, and snowfall. The complexity of the Weather Derivatives structure shows the weakness of the Black Scholes framework. Therefore, under the risk-neutral probability measure, the option price of a weather contract can be given as a unique solution of a two-dimensional partial differential equation (parabolic in one direction and hyperbolic in other directions), with an initial condition and subjected to adequate boundary conditions. To calculate the price of the option, one can use numerical methods such as the Monte Carlo simulations and implicit finite difference schemes conjugated with Semi-Lagrangian methods. This paper is proposed two explicit methods, namely, first-order upwind in the hyperbolic direction combined with Lax-Wendroff in the parabolic direction and first-order upwind in the hyperbolic direction combined with second-order upwind in the parabolic direction. One of the advantages of these methods is the fact that they take into consideration the boundary conditions obtained from the financial interpretation and deal efficiently with the different choices of the convection coefficients.

Keywords: incomplete markets, numerical methods, partial differential equations, stochastic process, weather derivatives

Procedia PDF Downloads 80

Authors: Sandra C. L. Dorea, Joann K. Whalen, Yixin Shao, Oumarou Savadogo

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The major challenge for industries that rely on fossil fuels in manufacturing processes or to provide goods and services is to lower their CO2 emissions, as the case for the manufacture of Portland cement. Feasible materials for this purpose can include agro-industrial or agricultural wastes, which are termed 'biosilica' since the silica was contained in a biological matrix (biomass). Corn cob (CC) has some characteristics that make it a good candidate as biosilica source: 1) it is an abundant grain crop produced around the world; 2) more production means more available residues is left in the field to be used. This work aims to evaluate the CC collected from different farms in Canada during the corn harvest in order to see if they can be used together as a biosilica source. The characterization of the raw CC was made in the physical, chemical, and thermal way. The moisture content, the granulometry, and the morphology were also analyzed. The ash content measured was 2,1%. The Thermogravimetric Analysis (TGA) and its Derivative (DTG) evaluated of CC as a function of weight loss with temperature variation ranging between 30°C and 800°C in an atmosphere of N2. The chemical composition and the presence of silica revealed that the different sources of the CC do not interfere in its basic chemical composition, which means that this kind of waste can be used together as a source of biosilica no matter where they come from. Then, this biosilica can partially replace the cement Portland making sustainable cementitious mixtures and contributing to reduce the CO2 emissions.

Keywords: biosilica, characterization, corn cob, sustainable cementitious materials

Procedia PDF Downloads 258

Authors: M. Khaledi Pour, P. Akbartehrani, M. Amini, M. Khani, M. Mohajeri Tehrani, R. Radi, B. Shokri

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Diabetic Foot Ulcer (DFU) is one of the costly severe complications of diabetes. Neuropathy and Peripheral Arterial Disease (PAD) due to diabetes are significant causes of this complication. In 10 years the patients with DFUs are twice as likely to die as patients without DFUs. Cold Atmospheric Plasma (CAP) is a promising tool for medical purposes. CAP generate reactive species at room temperature and are effective in killing bacteria and fibroblast proliferation. These CAP-based tools produce NO, which has bactericidal and angiogenesis properties. It also showed promising effects in the DFUs surface reduction and the time to wound closure. In this paper, we evaluated the effect of the Argon Plasma Jet (APJ) on the healing process of the Wagner Grade 2 DFUs in a randomized clinical trial. The 20 kHz sinusoidal voltage frequency derives the APJ. Patients (n=20) were randomly double-blinded assigned into two groups. These groups receive the standard care (SC, n=10) and the standard care with APJ treatment (SC+APJ, n=10) for five sessions in four weeks. The results showed that the APJ treatment along standard care could reduce the wound surface by 20 percent more than the standard care. Also, It showed a more influential role in controlling wound infection.

Keywords: argon plasma jet, cold atmospheric plasma, diabetes, diabetic foot ulcer

Procedia PDF Downloads 190

Authors: Hye Jin Kim, Hwa Sung Shin

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Ischemic stroke means the caused brain damage due to neurological defects, occurring occlusion of cerebral vascular resulting in thrombus or embolism. t-PA (tissue Plasminogen Activator) is the only thrombolytic agent passed the FDA (Food and Drug Administration). However, t-PA directly dissolves the thrombus (direct activity) through fibrinolysis, showing side effects such as re-occlusion. In this study, we evaluated the thrombolytic activities of the serine protease extracted from lugworms inhabiting tidal flats. The new serine protease identified as 38 kDa by SDS-PAGE was not toxic to brain endothelial cells line (hCMEC/D3). Also, the plasmin synthesis inhibition activity (indirect activity) of the new serine protease was confirmed through fibrin zymography assay and fibrin plate assay. It was higher than direct activity as compared to u-PA (urokinase Plasminogen Activator). The activities were found to be maintained at a wide range of temperature (4-70 ℃) and pH 7-10 compared to previous thrombolytic agents from the azocasein assay. In addition, the new serine protease has shown anticoagulant activity from fibrinogenolytic activity assay. In conclusion, the serine protease in lug worms inhabiting the tidal flats could be considered a promising thrombolytic candidate for the treatment of ischemic stroke.

Keywords: alkaline serine protease, bifunctional thrombolytic activity, fibrinolytic activity, ischemic stroke, lug worms

Procedia PDF Downloads 319

Authors: Amin Noor, Roslinda Nazar, Norihan Md. Arifin

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In this paper, a numerical and theoretical study has been performed for the stagnation-point boundary layer flow and heat transfer towards a shrinking sheet in a nanofluid. The mathematical nanofluid model in which the effect of the nanoparticle volume fraction is taken into account is considered. The governing nonlinear partial differential equations are transformed into a system of nonlinear ordinary differential equations using a similarity transformation which is then solved numerically using the function bvp4c from Matlab. Numerical results are obtained for the skin friction coefficient, the local Nusselt number as well as the velocity and temperature profiles for some values of the governing parameters, namely the nanoparticle volume fraction Φ, the shrinking parameter λ and the Prandtl number Pr. Three different types of nanoparticles are considered, namely Cu, Al2O3 and TiO2. It is found that solutions do not exist for larger shrinking rates and dual (upper and lower branch) solutions exist when λ < -1.0. A stability analysis has been performed to show which branch solutions are stable and physically realizable. It is also found that the upper branch solutions are stable while the lower branch solutions are unstable.

Keywords: heat transfer, nanofluid, shrinking sheet, stability analysis, stagnation-point flow

Procedia PDF Downloads 377

Authors: Mahfoud Benzerzour, Mouhamadou Amar, Amine Safhi, Nor-Edine Abriak

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Significant volumes of sediment are annually dredged in France and all over the world. These materials may, in fact, be used beneficially as supplementary cementitious material. This paper studies the durability of a new cement matrix based on marine dredged sediment of Dunkirk-Harbor (north of France). Several techniques are used to characterize the raw sediment such as physical properties, chemical analyses, and mineralogy. The XRD analysis revealed quartz, calcite, kaolinite as main mineral phases. In order to eliminate organic matter and activate some of those minerals, the sediment is calcined at a temperature of 850°C for 1h. Moreover, four blended mortars were formulated by mixing a portland cement (CEM I 52,5 N) and the calcined sediment as partial cement substitute (0%, 10%, 20% and 30%). Reference mortars, based on the blended cement, were then prepared. This re-use cannot be substantiating and efficient without a durability study. In this purpose, the following tests, mercury porosity, accessible water porosity, chloride permeability, freezing and thawing, external sulfate attack, alkali aggregates reaction, compressive and bending strength tests were conducted on those mortars. The results of most of those tests evidenced the fact that the mortar that contains 10% of the treated sediment is efficient and durable as the reference mortar itself. That would infer that the presence of these calcined sediment improves mortar general behavior.

Keywords: sediment, characterization, calcination, substitution, durability

Procedia PDF Downloads 250

Authors: Andrew Green, Jiaming Liu, Kellathur Srinivasan, Raymond Chua

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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 359

Authors: Maik Kschischo, Dominik Kahl, Philipp Wendland, Andreas Weber

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Understanding and modelling of real-world complex dynamic systems in biology, engineering and other fields is often made difficult by incomplete knowledge about the interactions between systems states and by unknown disturbances to the system. In fact, most real-world dynamic networks are open systems receiving unknown inputs from their environment. To understand a system and to estimate the state dynamics, these inputs need to be reconstructed from output measurements. Reconstructing the input of a dynamic system from its measured outputs is an ill-posed problem if only a limited number of states is directly measurable. A first requirement for solving this problem is the invertibility of the input-output map. In our work, we exploit the fact that invertibility of a dynamic system is a structural property, which depends only on the network topology. Therefore, it is possible to check for invertibility using a structural invertibility algorithm which counts the number of node disjoint paths linking inputs and outputs. The algorithm is efficient enough, even for large networks up to a million nodes. To understand structural features influencing the invertibility of a complex dynamic network, we analyze synthetic and real networks using the structural invertibility algorithm. We find that invertibility largely depends on the degree distribution and that dense random networks are easier to invert than sparse inhomogeneous networks. We show that real networks are often very difficult to invert unless the sensor nodes are carefully chosen. To overcome this problem, we present a sensor node placement algorithm to achieve invertibility with a minimum set of measured states. This greedy algorithm is very fast and also guaranteed to find an optimal sensor node-set if it exists. Our results provide a practical approach to experimental design for open, dynamic systems. Since invertibility is a necessary condition for unknown input observers and data assimilation filters to work, it can be used as a preprocessing step to check, whether these input reconstruction algorithms can be successful. If not, we can suggest additional measurements providing sufficient information for input reconstruction. Invertibility is also important for systems design and model building. Dynamic models are always incomplete, and synthetic systems act in an environment, where they receive inputs or even attack signals from their exterior. Being able to monitor these inputs is an important design requirement, which can be achieved by our algorithms for invertibility analysis and sensor node placement.

Keywords: data-driven dynamic systems, inversion of dynamic systems, observability, experimental design, sensor node placement

Procedia PDF Downloads 146

Authors: İsmail İnce, Ali Bozdag, Ayla Bozdag, M. Bahadır Tosunlar, M. Ergun Hatır, Mustafa Korkanc

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The building stones used in the construction of historical structures are exposed to atmospheric effects directly or indirectly. As a result of this process, building stones are partially or completely degraded. Historical buildings are important symbols of cultural heritage, so it is very significant to transfer to the future generations by protecting and repairing of these historical buildings. The Eflatunpınar Hitit Monument located near the Eflatunpınar cold water spring was constructed by using natural rock blocks during the Hittites Empire period. The monument has been protected without losing its function until today. The purpose of this study is to evaluate the deteriorations in the Eflatunpınar Hitit Monument and to detect the water chemistry of the Eflatunpınar spring located around the Beysehir County in the west of Konya. For this purpose, the petrographic and mechanical properties of the rocks used in this monument were determined, and the deteriorations in the monument were determined with the aid of non-destructive test methods including Schmidt hardness value, relative humidity measurement, thermal imaging. Additionally, the physical (electrical conductivity (EC), pH and temperature) and chemical characteristics (major anions and cations) of the Eflatunpınar cold water spring have been detected.

Keywords: deteriorations, Eflatunpınar Hitit monument, Eflatunpınar spring, Konya, non-destructıve tests

Procedia PDF Downloads 162

Authors: R. Khrifou, M. Galai, R. Touir, M. Ebn Touhami, Y. Ramli

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A 2-(5-methyl-2-Nitro-1H-imidazol-1-yl)ethyl benzoate (IMDZ-B) was synthesized and characterized using elemental analyses, NMR, and Fourier transform infrared (FTIR) techniques. Its effect on brass corrosion in 1.0 M H₃PO₄ solution was investigated by using electrochemical measurements coupled with X-ray diffraction analysis (XRD), Scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX). The polarization measurements showed that the IMDZ-B acts as a mixed-type inhibitor. Indeed, it is found that the IMDZ-B compound is a very good inhibitor, and its inhibition efficiency increases with concentration to reach a maximum of 99.5 % at 10-³ M. In addition, the obtained electrochemical parameters from impedance indicated that the IMDZ-B molecules act by adsorption on metallic surfaces. This adsorption was found to obey Langmuir’s adsorption isotherm. However, the temperature effect on the performance of IMDZ-B was also studied. It is found that the IMDZ-B takes its performance at high temperatures. In addition, the obtained kinetic and thermodynamic parameters showed that the IMDZ-B molecules act via two adsorption modes, physisorption and chemisorptions, and its process is endothermic and spontaneous. Finally, the XRD and SEM/EDX analyses confirmed the electrochemical obtained results.

Keywords: low concentration, anti-corrosion brass, IMDZ-B product, phosphoric acid solution, electrochemical, SEM\EDAX analysis

Procedia PDF Downloads 61

Authors: Byung Wook Yang, Jong Dae Park, Wang Soo Shin, Ji-Hyeon Song, Seo-Yun Choi, Boo-Yong Lee, Young Tae Hahm

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Korean ginseng (Panax ginseng C. A. Meyer) is frequently taken orally as a traditional herbal medicine with ginsenosides as the main pharmacological component in Asian countries, and its use is increasing worldwide. Recently, the increase in global temperature has been reported to cause various kinds of biological disorders induced by heat stress in human. The standardized black ginseng extract (SBGE; KGR-BG1) was developed in our biological screening experiment on the thermo-regulation, whose chemical characteristics were evaluated as ginsenoside Rg1, Rb1, Rg3(S), as well as Re, Rf, Rg2(S), Rh1(S), Rh2(S), and Rg5+Rk1. Heat stress responses such as body weight, food intake, water consumption have been measured when treated with Standardized Black Ginseng Extract (SBGE) in the animal experiment and also, biomarkers. SBGE treated group has been found to inhibit a decrease in body weight, a decrease in food intake and an increase in the water consumption when compared with non-treated group against environmental heat stress. These results suggest that SBGE might have a protective effect against environmental heat stress. And also, the several factors of stress response on the immune system need to be done for further studies and its evaluation is in progress.

Keywords: ginseng, ginsenoside, standardization, heat stress, immunomodulatory effect

Procedia PDF Downloads 294