Search results for: essential metals

Authors: T. Maruyama, T. Saida, S. Naritsuka, S. Iijima

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Single-walled carbon nanotubes (SWCNTs) are generally synthesized by chemical vapor deposition (CVD) using Fe, Co, and Ni as catalysts. However, due to the Ostwald ripening of metal catalysts, the diameter distribution of the grown SWCNTs is considerably wide (>2 nm), which is not suitable for electronics applications. In addition, reduction in the growth temperature is desirable for fabricating SWCNT devices compatible with the LSI process. Herein, we performed SWCNT growth by alcohol catalytic CVD using platinum-group metal catalysts (Pt, Rh, and Pd) because these metals have high melting points, and the reduction in the Ostwald ripening of catalyst particles is expected. Our results revealed that web-like SWCNTs were obtained from Pt and Rh catalysts at growth temperature between 500 °C and 600 °C by optimizing the ethanol pressure. The SWCNT yield from Pd catalysts was considerably low. By decreasing the growth temperature, the diameter and chirality distribution of SWCNTs from Pt and Rh catalysts became small and narrow. In particular, the diameters of most SWCNTs grown using Pt catalysts were below 1 nm and their diameter distribution was considerably narrow. On the contrary, SWCNTs can grow from Rh catalysts even at 300 °C by optimizing the growth condition, which is the lowest temperature recorded for SWCNT growth. Our results demonstrated that platinum-group metals are useful for the growth of small-diameter SWCNTs and facilitate low-temperature growth.

Keywords: Carbon nanotube, chemical vapor deposition, catalyst, Pt, Rh, Pd.

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Authors: A. Soualem

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The design of multi stage deep drawing processes requires the evaluation of many process parameters such as the intermediate die geometry, the blank shape, the sheet thickness, the blank holder force, friction, lubrication etc..These process parameters have to be determined for the optimum forming conditions before the process design. In general sheet metal forming may involve stretching drawing or various combinations of these basic modes of deformation. It is important to determine the influence of the process variables in the design of sheet metal working process. Especially, the punch and die corner for deep drawing will affect the formability. At the same time the prediction of sheet metals springback after deep drawing is an important issue to solve for the control of manufacturing processes. Nowadays, the importance of this problem increases because of the use of steel sheeting with high stress and also aluminum alloys.

The aim of this paper is to give a better understanding of the springback and its effect in various sheet metals forming process such as expansion and restreint deep drawing in the cup drawing process, by varying radius die, lubricant for two commercially available materials e.g. galvanized steel and Aluminum sheet. To achieve these goals experiments were carried out and compared with other results. The original of our purpose consist on tests which are ensured by adapting a U-type stretching-bending device on a tensile testing machine, where we studied and quantified the variation of the springback.

Keywords: Deep drawing, Expansion, Restreint deep drawing, Springback.

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Authors: L. Khalfa, M. Bagane, M. L. Cervera, S. Najjar

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The aim of this work is to present a low cost adsorbent for removing toxic heavy metals from aqueous solutions. Therefore, we are interested to investigate the efficiency of natural clay minerals collected from south Tunisia and their modified form using sulfuric acid in the removal of toxic metal ions: Zn(II) and Pb(II) from synthetic waste water solutions. The obtained results indicate that metal uptake is pH-dependent and maximum removal was detected to occur at pH 6. Adsorption equilibrium is very rapid and it was achieved after 90 min for both metal ions studied. The kinetics results show that the pseudo-second-order model describes the adsorption and the intraparticle diffusion models are the limiting step. The treatment of natural clay with sulfuric acid creates more active sites and increases the surface area, so it showed an increase of the adsorbed quantities of lead and zinc in single and binary systems. The competitive adsorption study showed that the uptake of lead was inhibited in the presence of 10 mg/L of zinc. An antagonistic binary adsorption mechanism was observed. These results revealed that clay is an effective natural material for removing lead and zinc in single and binary systems from aqueous solution.

Keywords: Lead, zinc heavy metal, activated clay, kinetic study, competitive adsorption, modeling.

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Authors: K. Krishnaprasad, Raghu V. Prakash

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Constant amplitude fatigue crack growth (FCG) tests were performed on dissimilar metal welded plates of Type 316L Stainless Steel (SS) and IS 2062 Grade A Carbon steel (CS). The plates were welded by TIG welding using SS E309 as electrode. FCG tests were carried on the Side Edge Notch Tension (SENT) specimens of 5 mm thickness, with crack initiator (notch) at base metal region (BM), weld metal region (WM) and heat affected zones (HAZ). The tests were performed at a test frequency of 10 Hz and at load ratios (R) of 0.1 & 0.6. FCG rate was found to increase with stress ratio for weld metals and base metals, where as in case of HAZ, FCG rates were almost equal at high ΔK. FCG rate of HAZ of stainless steel was found to be lowest at low and high ΔK. At intermediate ΔK, WM showed the lowest FCG rate. CS showed higher crack growth rate at all ΔK. However, the scatter band of data was found to be narrow. Fracture toughness (Kc) was found to vary in different locations of weldments. Kc was found lowest for the weldment and highest for HAZ of stainless steel. A novel method of characterizing the FCG behavior using an Infrared thermography (IRT) camera was attempted. By monitoring the temperature rise at the fast moving crack tip region, the amount of plastic deformation was estimated.

Keywords: Dissimilar metal weld, Fatigue Crack Growth, fracture toughness, Infrared thermography.

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Authors: Dimitrios J. Dimitriou

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Airport’s serving a tourist destination are an essential counterpart of the tourist demand supply chain, and their productivity is related to the region’s attractiveness and is enhanced by the air transport business. In this paper, the evaluation framework of the scheduled flights between two tourist airports is taken into consideration. By adopting a systemic approach, the arrivals from an airport that its connectivity heavily depended on the departures of another major airport are reviewed. The methodology framework, based on inventory control theory and the numerical example, promotes the use of the modelling formulation. The results would be essential for comparison and exercising to other similar cases.

Keywords: Airport connectivity, inventory control, optimization, optimum allocation.

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Authors: Entela Haloci, Stefano Manfredini, Vilma Toska, Silvia Vertuani, Paola Ziosi, Irma Topi, Henri Kolani

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Antifungal activities of ether and methanolic extracts of volatiles oils of Nigella Sativa seeds were tested against pathogenic bacterias and fungies strains.The volatile oil were found to have significant antifungal and antibacterial activities compare to tetracycline, cefuroxime and ciprofloxacin positive controls.The ether and methanolic esxtracts were compared to each other for antifungal and antibacterial activities and ether extracts showed stonger activity than methanolic one.

Keywords: Antifungal, antibacterial, essential oils, extraction, Nigella Sativa.

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Authors: I. Cano-Aguilera, B. E. Rubio-Campos, G. De la Rosa, A. F. Aguilera-Alvarado

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Mining tailings represent a generating source of rich heavy metal material with a potential danger the public health and the environment, since these metals, under certain conditions, can leach and contaminate aqueous systems that serve like supplying potable water sources. The strategy for this work is based on the observation, experimentation and the simulation that can be obtained by binding real answers of the hydrodynamic behavior of metals leached from mining tailings, and the applied mathematics that provides the logical structure to decipher the individual effects of the general physicochemical phenomenon. The case of study presented herein focuses on mining tailings deposits located in Monte San Nicolas, Guanajuato, Mexico, an abandoned mine. This was considered the contamination source that under certain physicochemical conditions can favor the metal leaching, and its transport towards aqueous systems. In addition, the cartography, meteorology, geology and the hydrodynamics and hydrological characteristics of the place, will be helpful in determining the way and the time in which these systems can interact. Preliminary results demonstrated that arsenic presents a great mobility, since this one was identified in several superficial aqueous systems of the micro watershed, as well as in sediments in concentrations that exceed the established maximum limits in the official norms. Also variations in pH and potential oxide-reduction were registered, conditions that favor the presence of different species from this element its solubility and therefore its mobility.

Keywords: Arsenic, mining tailings, transport.

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Authors: Nurcihan Hacioglu, Cigdem Gul, Murat Tosunoglu

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In this article, the antibiogram and heavy metal resistance profile of the bacteria isolated from total 34 studied animals (Pelophylax ridibundus = 12; Mauremys rivulata = 14; Natrix natrix = 8) captured around the Biga Stream, are described. There was no database information on antibiogram and heavy metal resistance profile of bacteria from these area’s amphibians and reptiles. A total of 200 bacteria were successfully isolated from cloaca and oral samples of the aquatic amphibians and reptiles as well as from the water sample. According to Jaccard’s similarity index, the degree of similarity in the bacterial flora was quite high among the amphibian and reptile species under examination, whereas it was different from the bacterial diversity in the water sample. The most frequent isolates were A. hydrophila (31.5%), B. pseudomallei (8.5%), and C. freundii (7%). The total numbers of bacteria obtained were as follows: 45 in P. ridibundus, 45 in N. natrix 30 in M. rivulata, and 80 in the water sample. The result showed that cefmetazole was the most effective antibiotic to control the bacteria isolated in this study and that approximately 93.33% of the bacterial isolates were sensitive to this antibiotic. The multiple antibiotic resistances (MAR) index indicated that P. ridibundus (0.95) > N. natrix (0.89) > M. rivulata (0.39). Furthermore, all the tested heavy metals (Pb+2, Cu+2, Cr+3, and Mn+2) inhibit the growth of the bacterial isolates at different rates. Therefore, it indicated that the water source of the animals was contaminated with both antibiotic residues and heavy metals.

Keywords: Amphibian, Bacteriological Quality, Reptile, Antibiotic & Heavy Metal Resistance.

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Authors: R. U. Hamzah, H. L. Muhammad, A. Sayyadi, M. B Busari, R. Garba, M. B. Umar, A. N Abubakar

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Lead (Pb) and Cadmium (Cd) are toxic, non-essential transition metals that pose many health risks for both humans and animals. They are environmental toxicants which contribute to testicular damage resulting to infertility problem among male populace worldwide. Chelating agents used for lead and cadmium toxicity are not readily available, toxic, expensive and unable to mop up most of the toxic metals accumulated in various organs. In this study, the effect of crude extract (CE), ethyl acetate fraction (EF) and acetone fraction (AF) of Pterocarpus mildbraedii leaf extract was assessed on cadmium-lead chloride induced testicular damaged in male albino Wistar rats. CE of the leaf was obtained by extracting in absolute methanol which was further subjected to solvent partitioning via vacuum liquid chromatographic (VLC) techniques using ethyl acetate, acetone and 70% methanol. A preliminary phytochemical screening and in vitro antioxidants guided activities on the CE and fractions were determined using standard methods. EF, AF and CE which exhibited significant in vitro activity were subjected to an in vivo study using Wistar rats. In vivo antioxidant markers, male reproductive hormones, testicular enzymes and DNA damage markers were analyzed on the rats’ testes supernatant. AF had the highest quantities of phenols (319.00 mg/g), flavonoids (8.87 mg/g) and tannins (8.87 mg/g) while methanol and EFs were richer in saponins (135.32 µg/g) and alkaloids (38.34 µg/g) respectively. A dose dependent 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP) and lipid peroxidation were observed in all the extract with high antioxidants power in CE and AF. Administration of lead-cadmium chloride solution significantly (p > 0.05) decreases the testicular superoxide dismutase (SOD) activity to 6.82 unit/mg protein, Catalase (CAT) activity to 8.07 of H2O2 consumed/unit/mg protein and Glutathione (GSH) concentration to 31.30 ug/mg protein. There was a concomitant increase in the level of Malondialdehyde (MDA) to a value of 23.70 mmol/mg protein. In addition, lead-cadmium chloride solution significantly (p > 0.05) increases the testicular marker enzymes (Alkaline phosphatase (119.57 u/L), lactate dehydrogenase (357.05 u/L), Acid phosphatase (98.65 u/L)) and DNA damage markers (conjugated dienes (93.39 nmol/mg protein), carbonyl protein (35.39 nmol/mg protein), DNA fragmentation percentage (32.12%)) with lowered testicular hormones (Testosterone (3.1 ng/mL), Follicle stimulating (0.35 IU/mL) and Luteinizing hormones (0.15 IU/mL)) of the animals in negative control group when compared with other treated groups. Treatment with Pterocarpus mildbraedii leaf extract reverts the observed changes with the best activities found in the CE and AFs in a dose dependent manner. Pterocarpus mildbraedii leaf extract ameliorated the lead/cadmium induced testicular damage in male albino rats. The restoration of the aforementioned parameters by some of the extract dosages were comparable to the standard drug with higher activities in the crude and AF. Therefore, Pterocarpus mildbraedii leaf extract can be explored further for the management of lead/cadmium induced toxicity.

Keywords: Cadmium, lead, Pterocarpus mildbraedii, testicular damage.

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Authors: M. Foroutan, H. Dalayeli, M. Sadeghian

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In this paper processes including large deformations of a rubber with hyperelastic material behavior are simulated by the RKPM method. Due to the loss of kronecker delta properties in the mesh less shape functions, the imposition of essential boundary conditions consumes significant CPU time in mesh free computations. In this work transformation method is used for imposition of essential boundary conditions. A RKPM material shape function is used in this analysis. The support of the material shape functions covers the same set of particles during material deformation and hence the transformation matrix is formed only once at the initial stages. A computer program in MATLAB is developed for simulations.

Keywords: RKPM, large deformations, transformation, essentialboundary conditions.

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Authors: V. C. Shruti, P. F. Rodríguez-Espinosa, D. C. Escobedo-Urías, Estefanía Martinez Tavera, M. P. Jonathan

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Atoyac River, a major south-central river flowing through the states of Puebla and Tlaxcala in Mexico is significantly impacted by the natural volcanic inputs in addition with wastewater discharges from urban, agriculture and industrial zones. In the present study, core samples were collected from R. Atoyac and analyzed for sediment granularity, major (Al, Fe, Ca, Mg, K, P and S) and trace elemental concentrations (Ba, Cr, Cd, Mn, Pb, Sr, V, Zn, Zr). The textural studies reveal that the sediments are mostly sand sized particles exceeding 99% and with very few to no presence of mud fractions. It is observed that most of the metals like (avg: all values in μg g^-1) Ca (35,528), Mg (10,789), K (7453), S (1394), Ba (203), Cr (30), Cd (4), Pb (11), Sr (435), Zn (76) and Zr (88) are enriched throughout the sediments mainly sourced from volcanic inputs, source rock composition of Atoyac River basin and industrial influences from the Puebla city region. Contamination indices, such as anthropogenic factor (AF), enrichment factor (EF) and geoaccumulation index (I_geo), were used to investigate the level of contamination and toxicity as well as quantitatively assess the influences of human activities on metal concentrations. The AF values (>1) for Ba, Ca, Mg, Na, K, P and S suggested volcanic inputs from the study region, where as Cd and Zn are attributed to the impacts of industrial inputs in this zone. The EF and I_geo values revealed an extreme enrichment of S and Cd. The ecological risks were evaluated using potential ecological risk index (RI) and the results indicate that the metals Cd and V pose a major hazard for the biological community.

Keywords: Atoyac River, contamination indices, metal concentrations, Mexico, textural studies.

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Authors: Gintarė Sauliutė, Gintaras Svecevičius

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Landfill leachates contain a number of persistent pollutants, including heavy metals. They have the ability to spread in ecosystems and accumulate in fish which most of them are classified as top-consumers of trophic chains. Fish are freely swimming organisms; but perhaps, due to their species-specific ecological and behavioral properties, they often prefer the most suitable biotopes and therefore, did not avoid harmful substances or environments. That is why it is necessary to evaluate the persistent pollutant dispersion in hydroecosystem using fish tissue metal concentration. In hydroecosystems of hybrid type (e.g. river-pond-river) the distance from the pollution source could be a perfect indicator of such a kind of metal distribution. The studies were carried out in the Kairiai landfill neighboring hybrid-type ecosystem which is located 5 km east of the Šiauliai City. Fish tissue (gills, liver, and muscle) metal concentration measurements were performed on two types of ecologically-different fishes according to their feeding characteristics: benthophagous (Gibel carp, roach) and predatory (Northern pike, perch). A number of mathematical models (linear, non-linear, using log and other transformations) have been applied in order to identify the most satisfactorily description of the interdependence between fish tissue metal concentration and the distance from the pollution source. However, the only one log-multiple regression model revealed the pattern that the distance from the pollution source is closely and positively correlated with metal concentration in all predatory fish tissues studied (gills, liver, and muscle).

Keywords: Bioaccumulation in fish, heavy metals, hydroecosystem, landfill leachate, mathematical model.

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Authors: Lalita Saeaeh, Sirirat Jitkarnka

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Pyrolysis of waste tire is one of alternative technique to produce petrochemicals, such as light olefins, mixed C4, and monoaromatics. Noble metals supported on acid zeolite catalysts were reported as potential catalysts to produce the high valuable products from waste tire pyrolysis. Especially, Pd supported on HBeta gave a high yield of olefins, mixed C4, and mono-aromatics. Due to the high prices of noble metals, the objective of this work was to investigate whether or not a non-noble Ni metal can be used as a substitute of a noble metal, Pd, supported on HBeta as a catalyst for waste tire pyrolysis. Ni metal was selected in this work because Ni has high activity in cracking, isomerization, hydrogenation and the ring opening of hydrocarbons Moreover, Ni is an element in the same group as Pd noble metal, which is VIIIB group, aiming to produce high valuable products similarly obtained from Pd. The amount of Ni was varied as 5, 10, and 20% by weight, for comparison with a fixed 1 wt% Pd, using incipient wetness impregnation. The results showed that as a petrochemical-producing catalyst, 10%Ni/HBeta performed better than 1%Pd/HBeta because it did not only produce the highest yield of olefins and cooking gases, but the yields were also higher than 1%Pd/HBeta. 5%Ni/HBeta can be used as a substitute of 1%Pd/HBeta for similar crude production because its crude contains the similar amounts of naphtha and saturated HCs, although it gave no concentration of light mono-aromatics (C6-C11) in the oil. Additionally, 10%Ni/HBeta that gave high olefins and cooking gases was found to give a fairly high concentration of the light mono-aromatics in the oil.

Keywords: Catalytic pyrolysis; Waste tire; Pd; Ni; HBeta

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Authors: M. A. Abou Donia, A. A. K. Abou-Arab, Nevin E. Sharaf, A. K. Enab, Sherif R. Mohamed

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Lead (Pb) poisoning is one of the most common and preventable environmental health problems. There are different sources of environmental pollution with lead as lead alkyl additives in petrol and manufacturing processes. Pb in the atmosphere can be deposited in urban soils, and may then be re-suspended to re-enter the atmosphere. This could increase human exposure to Pb and cause long-term health effects. Thus, monitoring Pb pollution is considered one of the major tasks in controlling pollution. Scalp hair can be utilized for the determination of lead (Pb) concentration. It provides a lasting record of metal intakes of weeks or even months, and for most metals, their accumulation in hair reflects their accumulation in the whole body. This work was conducted to investigate the concentration of lead in male scalp hair of Cairo (residential-traffic and residential-industrial) and rural residents after twenty years of phasing out of leaded gasoline. Results indicated that the mean concentration of lead in hair of residential-traffic (9.7552 μg/g ±0.71) and residential-industrial (12.3288 μg/g ±1.13) was significantly higher than that in rural residents (4.7327 μg/g ±0.67). The mean concentration of lead in hair of resident’s industrial areas was the highest among Cairo residents and not the traffic areas as it was before phasing out of leaded gasoline. Twenty years of phasing out of leaded gasoline in Cairo has greatly improved the lead pollution among residents of traffic areas, but industrial areas residents were still suffering from lead pollution, which needs more efforts to control the sources of lead pollution.

Keywords: Heavy metals, lead, hair, biological sample, urban pollution, rural pollution.

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Authors: Vita Strazdina, Aleksandrs Jemeljanovs, Vita Sterna

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Not all proteins have the same nutritional value, since protein quality strongly depends on its amino acid composition and digestibility. The meat of game animals could be a high protein source because of its well-balanced essential amino acids composition. Investigations about biochemical composition of game meat such as wild boar (Sus scrofa scrofa), roe deer (Capreolus capreolus) and beaver (Castor fiber) are not very much. Therefore, the aim of the investigation was evaluate protein composition of game meat hunted in Latvia. The biochemical analysis, evaluation of connective tissue and essential amino acids in meat samples were done, the amino acids score were calculate. Results of analysis showed that protein content 20.88-22.05% of all types of meat samples is not different statistically. The content of connective tissue from 1.3% in roe deer till 1.5% in beaver meat allowed classified game animal as high quality meat. The sum of essential amino acids in game meat samples were determined 7.05–8.26g100g-1. Roe deer meat has highest protein content and lowest content of connective tissues among game meat hunted in Latvia. Concluded that amino acid score for limiting amino acids phenylalanine and tyrosine is high and shows high biological value of game meat.

Keywords: Dietic product, game meat, amino acids, scores.

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Authors: Hanen Nafaa, Maissa Farhat, Sina Ouriemi, Sbita Lassaad

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The use of renewable energies is growing significantly worldwide. Faced with the increasing demand for electrical energy, mainly for the needs of remote, deserted and mountainous regions, numerous applications use photovoltaic energy. In this sense, the proposed study concerns a mathematical modeling and an experimental validation for the recovery of essential oil by a steam distillation system using photovoltaic energy. In this paper, we proceed to a modeling of the solar system that includes a photovoltaic (PV) generator with an electronic power converter allowing a continuation of the optimum operating point. The results obtained are promising and are validated practically.

Keywords: Boiling in tubes, DC-DC converter, desalination, maximum power point tracking command, photovoltaic energy, solar generator.

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Authors: Je-Hoon Michael Oh

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The major source of allergy in home is the house dust mite (Dematophagoides farina, Dermatophagoides pteronyssinus) causing allergic symptom include atopic dermatitis, asthma, perennial rhinitis and even infant death syndrome. Control of this mite species is dependent on the use of chemical methods such as fumigation treatments with methylene bromide, spraying with organophosphates such as pirimiphos-methyl, or treatments with repellents such as DEET and benzyl benzoate. Although effective, their repeated use for decades has sometimes resulted in development of resistance and fostered environmental and human health concerns. Both decomposing animal parts and the protein that surrounds mite fecal pellets cause mite allergy. So it is more effective to repel than to kill them because allergen is not living house dust mite but dead body or fecal particles of house dust mite. It is important to find out natural repellent material against house dust mite to control them and reduce the allergic reactions. Plants may be an alternative source for dust mite control because they contain a range of bioactive chemicals. The research objectives of this paper were to verify the acaricidal and repellent effects of cinnamon essential oil and to find out it-s most effective concentrations. We could find that cinnamon bark essential oil was very effective material to control the house dust mite. Furthermore, it could reduce chemical resistance and danger for human health.

Keywords: house dust mite, cinnamon, repellent effect

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Authors: Bita Mashayekhi, Seyed Meisam Tabatabaie Nasab

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Intellectual capital is one of the most valuable and important parts of the intangible assets of enterprises especially in knowledge-based enterprises. With respect to increasing gap between the market value and the book value of the companies, intellectual capital is one of the components that can be placed in this gap. This paper uses the value added efficiency of the three components, capital employed, human capital and structural capital, to measure the intellectual capital efficiency of Iranian industries groups, listed in the Tehran Stock Exchange (TSE), using a 8 years period data set from 2005 to 2012. In order to analyze the effect of intellectual capital on the market-to-book value ratio of the companies, the data set was divided into 10 industries, Banking, Pharmaceutical, Metals & Mineral Nonmetallic, Food, Computer, Building, Investments, Chemical, Cement and Automotive, and the panel data method was applied to estimating pooled OLS. The results exhibited that value added of capital employed has a positive significant relation with increasing market value in the industries, Banking, Metals & Mineral Nonmetallic, Food, Computer, Chemical and Cement, and also, showed that value added efficiency of structural capital has a positive significant relation with increasing market value in the Banking, Pharmaceutical and Computer industries groups. The results of the value added showed a negative relation with the Banking and Pharmaceutical industries groups and a positive relation with computer and Automotive industries groups. Among the studied industries, computer industry has placed the widest gap between the market value and book value in its intellectual capital.

Keywords: Capital Employed, Human Capital, Intellectual Capital, Market-to-Book Value, Structural Capital, Value Added Efficiency.

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Authors: Daniel C. S. Lim

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There are numerous nutritional supplements, such as multivitamins and nutrition drinks, in the market today. Many of these supplements are expensive and tend to be driven commercially by business decisions and big marketing budgets. Many of the costs are ultimately borne by the end user in the quest for keeping to a healthy lifestyle. This paper proposes a system with a list of ten determinants to gauge how to decide the value of various supplements. It suggests variables such as composition, safety, efficacy and bioavailability, as well as several other considerations. These guidelines can help to tackle many of the issues that people of all ages face in the way that they receive essential nutrients. The system also aims to promote and improve the safety and choice of foods and supplements. In so doing, the system aims to promote the individual’s or population’s control over their own health and reduce the growing health care burden on the society.

Keywords: Nutritional supplements, vitamins and minerals, bioavailability, supplementation determinants, nutrition guidelines.

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Authors: O. Abramova, L. Abukova, A. Goreva, G. Isaeva

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The present work was made for the purpose of evaluating the interstitial water’s role in the mobilization of metal elements of clay deposits and occurrences in sedimentary formation in the hydro-geological basins. The experiments were performed by using a special facility, which allows adjusting the pressure, temperature, and the frequency of the acoustic vibrations. The dates for study were samples of the oil shales (Baltic career, O₂kk) and clay rocks, mainly montmorillonite composition (Borehole SG-12000, the depth of selection 1000–3600 m, the Azov-Kuban trough, N₁). After interstitial water squeezing from the rock samples, decrease in the original content of the rock forming components including trace metals V, Cr, Co, Ni, Cu, Zn, Zr, Mo, Pb, W, Ti, and others was recorded. The experiments made it possible to evaluate the ore elements output and organic matters with the interstitial waters. Calculations have shown that, in standard conditions, from each ton of the oil shales, 5-6 kg of ore elements and 9-10 kg of organic matter can be escaped. A quantity of matter, migrating from clays in the process of solidification, is changed depending on the lithogenesis stage: more recent unrealized deposits lose more ore and organic materials than the clay rocks, selected from depth over 3000 m. Each ton of clays in the depth interval 1000-1500 m is able to generate 3-5 kg of the ore elements and 6-8 kg of the organic matters. The interstitial waters are a freight forwarder over transferring these matters in the reservoir beds. It was concluded that the interstitial waters which escaped from the study samples are solutions with abnormal high concentrations of the metals and organic matters. In the discharge zones of the sediment basins, such fluids can create paragenetic associations of the sedimentary-catagenetic ore and hydrocarbon mineral resources accumulations.

Keywords: Hydrocarbons, ore genesis, paragenesis, interstitial waters.

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Authors: Qatawneh H., Yousef S., Shirvani H.

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The purpose of this article is to propose a model designed to achieve Total Knowledge Transfer in the public health sector. The Total Knowledge Transfer Model integrated four essential organizational factors which have been under examined in totality in the literature. The research design was inductive in nature and used a case study for accomplishing the research objectives. The researcher investigated the factors that created a base to design a framework for total knowledge transfer in the public health sector. The results of this study are drawn from a fairly large sample in only two hospitals. A further research can be conducted to cover more responses from a wider health sector. The Total Knowledge Transfer Model is essential to improve the transfer and application of total common health knowledge.

Keywords: Health Care, Knowledge Management, Knowledge Transfer.

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Authors: B. Sadepovich Maikanov, Z. Shabanbayevich Adilbekov, R. Husainovna Mustafina, L. Tyulegenovna Auteleyeva

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This study involves detailed information about contaminants of honey in the Republic of Kazakhstan. The requirements of the technical regulation ‘Requirements to safety of honey and bee products’ and GOST 19792-2001 were taken into account in this research. Contamination of honey by antibiotics wqs determined by the IEA (immune-enzyme analysis), Ridder analyzer and Tecna produced test systems. Voltammetry (TaLab device) was used to define contamination by salts of heavy metals and gamma-beta spectrometry, ‘Progress BG’ system, with preliminary ashing of the sample of honey was used to define radioactive contamination. This article pointed out that residues of chloramphenicol were detected in 24% of investigated products, in 22% of them –streptomycin, in 7.3% - sulfanilamide, in 2.4% - tylosin, and in 12% - combined contamination was noted. Geographically, the greatest degree of contamination of honey with antibiotics occurs in the Northern Kazakhstan – 54.4%, and Southern Kazakhstan - 50%, and the lowest in Central and Eastern Kazakhstan with 30% and 25%, respectively. Generally, pollution by heavy metals is within acceptable limits, but the contamination from lead is highest in the Akmola region. The level of radioactive cesium and strontium is also within acceptable concentrations. The highest radioactivity in terms of cesium was observed in the East Kazakhstan region - 49.00±10 Bq/kg, in Akmola, North Kazakhstan and Almaty - 12.00±5, 11.05±3 and 19.0±8 Bq/kg, respectively, while the norm is 100 Bq/kg. In terms of strontium, the radioactivity in the East Kazakhstan region is 25.03±15 Bq/kg, while in Akmola, North Kazakhstan and Almaty regions it is 12.00±3, 10.2±4 and 1.0±2 Bq/kg, respectively, with the norm of 80 Bq/kg. This accumulation is mainly associated with the environmental degradation, feeding and treating of bees. Moreover, in the process of collecting nectar, external substances can penetrate honey. Overall, this research determines factors and reasons of honey contamination.

Keywords: Antibiotics, contamination of honey, honey, radionuclides.

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Authors: I. V. Singh, A. Singh

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In this paper, mesh-free element free Galerkin (EFG) method is extended to solve two-dimensional potential flow problems. Two ideal fluid flow problems (i.e. flow over a rigid cylinder and flow over a sphere) have been formulated using variational approach. Penalty and Lagrange multiplier techniques have been utilized for the enforcement of essential boundary conditions. Four point Gauss quadrature have been used for the integration on two-dimensional domain (Ω) and nodal integration scheme has been used to enforce the essential boundary conditions on the edges (┌). The results obtained by EFG method are compared with those obtained by finite element method. The effects of scaling and penalty parameters on EFG results have also been discussed in detail.

Keywords: Meshless, EFG method, potential flow, Lagrange multiplier method, penalty method, penalty parameter and scaling parameter

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Authors: A. S. Kipcak, O. Dere Ozdemir, E. Moroydor Derun, M. B. Piskin

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Tea has several types of essential elements. Potassium, magnesium and phosphorus are some examples of these elements. Tea is widely used drink in Turkey, also some people puts a lemon wedge to tea for different taste. In this study potassium, magnesium and phosphorus contents after the hot water brewing of black and green tea were determined by Optical Emission Spectroscopy (ICPOES). Furthermore, how the lemon addition to teas affects the concentrations of the potassium, magnesium and phosphorus amount are investigated. From the results, potassium, magnesium and phosphorus concentrations are found as 3003.3, 597.1, 1167.2 ppm in black tea and 3718.0, 3830.5, 376.4 ppm in green tea, respectively. After lemon addition potassium, magnesium and phosphorus concentrations are changed to 14930, 830.4, 1113.5 ppm in black tea and 15460.0, 909.5, 1152.5 ppm in green tea, respectively. It is seen that lemon addition affects some essential elements in black and green Turkish teas.

Keywords: Hot water brewing, ICP-OES, lemon, tea

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Authors: Nabil A. Ahmed

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This paper presents a novel three-phase utility frequency to high frequency soft switching power conversion circuit with dual mode pulse width modulation and pulse density modulation for high power induction heating applications as melting of steel and non ferrous metals, annealing of metals, surface hardening of steel and cast iron work pieces and hot water producers, steamers and super heated steamers. This high frequency power conversion circuit can operate from three-phase systems to produce high current for high power induction heating applications under the principles of ZVS and it can regulate its ac output power from the rated value to a low power level. A dual mode modulation control scheme based on high frequency PWM in synchronization with the utility frequency positive and negative half cycles for the proposed high frequency conversion circuit and utility frequency pulse density modulation is produced to extend its soft switching operating range for wide ac output power regulation. A dual packs heat exchanger assembly is designed to be used in consumer and industrial fluid pipeline systems and it is proved to be suitable for the hot water, steam and super heated steam producers. Experiment and simulation results are given in this paper to verify the operation principles of the proposed ac conversion circuit and to evaluate its power regulation and conversion efficiency. Also, the paper presents a mutual coupling model of the induction heating load instead of equivalent transformer circuit model.

Keywords: Induction heating, three-phase, conversion circuit, pulse width modulation, pulse density modulation, high frequency, soft switching.

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Authors: Sher Shermin Azmiri Khan, Syeda Jannatul Ferdous, Sushmita Chakraborty

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Over the last decades, biomedical engineering prosthetics become one of the most essential grounds. Prosthetic hands are rapidly evolving. Therefore, for designing prosthetic components, it is essential to improve quality such as make it affordable and improve patient comfort and mobility by making them lightweight and easy to wear. In this paper, we proposed a myoelectric controlled prosthesis hand. We can fabricate and manufacture customized cost-effective, small volumes of 3D printed hand which is interesting. The total weight of an adult hand is about 1000 gm including a battery. The prosthetic hand is built up with low-cost materials and techniques, the cost of manufacturing will be approximately US$145. The hand can grip objects of different shapes and sizes. The 3D printed hand can rotate its wrist like a human hand. The prosthetic hand is capable of showing some types of human gestures.

Keywords: Prosthetic Hand, sEMG, 3D printing, Arduino.

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Authors: Jacquelyn Nyenhuis, Jaroslaw W. Drelich

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Diets high in processed foods have been found to lack essential micro-nutrients for optimum human development and overall health. Some micro-nutrients such as copper (Cu) have been found to enhance the inflammatory response through its oxidative functions, thereby having a role in cardiovascular disease, metabolic syndrome, diabetes and related complications. This research study was designed to determine if food crops could be bio-fortified with micro-nutrients by growing sprouts on mineral fortified fiber mats. In the feasibility study described in this contribution, recycled cellulose fibers and clay, saturated with either micro-nutrient copper ions or copper nanoparticles, were converted to a novel mineral-cellulose fiber carrier of essential micro-nutrient and of antimicrobial properties. Seeds of Medicago sativa (alfalfa), purchased from a commercial, organic supplier were germinated on engineered cellulose fiber mats. After the appearance of the first leaves, the sprouts were dehydrated and analyzed for Cu content. Nutrient analysis showed ~2 increase in Cu of the sprouts grown on the fiber mats with copper particles, and ~4 increase on mats with ionic copper as compared to the control samples. This study illustrates the potential for the use of engineered mats as a viable way to increase the micro-nutrient composition of locally-grown food crops and the need for additional research to determine the uptake, nutritional implications and risks of micro-nutrient bio-fortification.

Keywords: Bio-fortification, copper nutrient uptake, sprout, mineral-fortified mat, micro-nutrient uptake.

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Authors: N. A. Salim, M. M. Othman, I. Musirin, M. S. Serwan

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Uncertainty of system operating conditions is one of the causative reasons which may render to the instability of a transmission system. For that reason, accurate assessment of transmission reliability margin (TRM) is essential to ensure effective power transfer between areas during the occurrence of system uncertainties. The power transfer is also called as the available transfer capability (ATC) which is the information required by the utilities and marketers to instigate selling and buying the electric energy. This paper proposes a computationally effective approach to estimate TRM and ATC by considering the uncertainties of system cascading collapse and transmission line outages. In accordance to the results that have been obtained, the proposed method is essential for the transmission providers which could help the power marketers and planning sectors in the operation and reserving transmission services based on the ATC calculated.

Keywords: Available transfer capability, System cascading collapse, Transmission line outages, Transmission reliability margin.

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Authors: Mahsa Tavakoli, Seyed Mohammad Hojjati, Yahya Kooch

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In this study, the effect of coal mining activities on lead and cadmium concentrations and distribution in soil was investigated in Hyrcanian forest, North Iran. 16 plots (20×20 m²) were established by systematic-randomly (60×60 m²) in an area of 4 ha (200×200 m²-mine entrance placed at center). An area adjacent to the mine was not affected by the mining activity; considered as the controlled area. In order to investigate soil lead and cadmium concentration, one sample was taken from the 0-10 cm in each plot. To study the spatial pattern of soil properties and lead and cadmium concentrations in the mining area, an area of 80×80m² (the mine as the center) was considered and 80 soil samples were systematic-randomly taken (10 m intervals). Geostatistical analysis was performed via Kriging method and GS⁺ software (version 5.1). In order to estimate the impact of coal mining activities on soil quality, pollution index was measured. Lead and cadmium concentrations were significantly higher in mine area (Pb: 10.97±0.30, Cd: 184.47±6.26 mg.kg^-1) in comparison to control area (Pb: 9.42±0.17, Cd: 131.71±15.77 mg.kg^-1). The mean values of the PI index indicate that Pb (1.16) and Cd (1.77) presented slightly polluted. Results of the NIPI index showed that Pb (1.44) and Cd (2.52) presented slight pollution and moderate pollution respectively. Results of variography and kriging method showed that it is possible to prepare interpolation maps of lead and cadmium around the mining areas in Hyrcanian forest. According to results of pollution and risk assessments, forest soil was contaminated by heavy metals (lead and cadmium); therefore, using reclamation and remediation techniques in these areas is necessary.

Keywords: Traditional coal mining, heavy metals, pollution indicators, geostatistics, caspian forest.

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Authors: Timothy B. Oppong, Haiyan Yang, Cecilia Amponsem-Boateng, Guangcai Duan

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The human palm has been identified as one of the richest habitats for human microbial accommodation making hand hygiene essential to primary prevention of infection. Since the hand is in constant contact with fomites which have been proven to be mostly contaminated, building hand hygiene habits is essential for the prevention of infection. This research was conducted to assess the hand hygiene habits of Ghanaian youths in Accra. This study used a survey as a quantitative method of research. The findings of the study revealed that out of the 254 participants who fully answered the questionnaire, 22% had the habit of washing their hands after outings while only 51.6% had the habit of washing their hands after using the bathroom. However, about 60% of the participants said they sometimes ate with their hands while 28.9% had the habit of eating with the hand very often, a situation that put them at risk of infection from their hands since some participants had poor handwashing habits; prompting the need for continuous education on hand hygiene.

Keywords: Hand hygiene, hand hygiene habits, hand washing, hand sanitizer use.

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