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541.
This study was a basic one to explore how much the aerodynamic characteristics of wind blade improve. The extent of improvement according to the shapes of groove placed on the surface of airfoil (NACA0015) was analyzed through computational analysis. A commercial computational fluid dynamics (CFD) code, the ANSYS Fluent 13, was used in this study. In this study, regarding with the positions and shapes of groove, the end of groove was placed at a certain distance (length, l) from both the front and back of separation starting point, the depth and the width were designated as h and d respectively. Analysis was conducted at the 7° angle of attack under the following conditions; the thickness (δ) of boundary layer to the depth (h) of groove ratio (h/δ) 0.6–1.0, the depth (h) of groove to the width (d) of groove ratio (h/d) 0.1–1.4, and the length (l) between the end of groove and separation point to the thickness (δ) of boundary layer ratio (l/δ) ?0.5–0.5. Among these conditions, the best improvement of lift to drag ratio, standing at 15.3%, was under h/δ = 1.0, h/d = 0.12, and l/δ = –0.5 (7° AOA, Re = 360k). In addition, throughout the range of angle of attack, 2–14°, lift to drag ratio improved by 0.8%, 5.1%, 3.2%, and 1.8% each when Reynolds numbers were 280k, 360k, 450k, and 530k. It is also confirmed that the shape of groove contributed to recovering velocity around airfoil wall and the lift to drag ratio improvements by groove were maintained at the given range of Reynolds number and around the angle of attack, 7°. 相似文献
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C. M. Shone T. J. S. Jothi 《Environmental science and pollution research international》2016,23(10):9364-9372
Dried leaves are a potential source of energy although these are not commonly used beside to satisfy daily energy demands in rural areas. This paper aims at preparing a leafy biomass feedstock in the form of briquettes which can be directly used for combustion or to extract the combustible gas using a gasifier. Teak (Tectona grandis) and rubber (Hevea brasiliensis) leaves are considered for the present study. A binder-assisted briquetting technique with tapioca starch as binder is adopted. Properties of these leafy biomass briquettes such as moisture content, calorific value, compressive strength, and shatter index are determined. From the study, briquettes with biomass-to-binder ratio of 3:5 are found to be stable. Higher mass percentage of binder is considered for preparation of briquettes due to the fact that leafy biomasses do not adhere well on densification with lower binder content. Ultimate analysis test is conducted to analyze the gasification potential of the briquettes. Results show that the leafy biomass prepared from teak and rubber leaves has calorific values of 17.5 and 17.8 MJ/kg, respectively, which are comparable with those of existing biomass feedstock made of sawdust, rice husk, and rice straw. 相似文献
545.
E. J. Ekuase T. J. van ‘t Erve L. W. Robertson M. W. Duffel G. Luthe 《Environmental science and pollution research international》2016,23(3):2119-2127
Determining the relationships between the structures of substrates and inhibitors and their interactions with drug-metabolizing enzymes is of prime importance in predicting the toxic potential of new and legacy xenobiotics. Traditionally, quantitative structure activity relationship (QSAR) studies are performed with many distinct compounds. Based on the chemical properties of the tested compounds, complex relationships can be established so that models can be developed to predict toxicity of novel compounds. In this study, the use of fluorinated analogues as supplemental QSAR compounds was investigated. Substituting fluorine induces changes in electronic and steric properties of the substrate without substantially changing the chemical backbone of the substrate. In vitro assays were performed using purified human cytosolic sulfotransferase hSULT2A1 as a model enzyme. A mono-hydroxylated polychlorinated biphenyl (4-OH PCB 14) and its four possible mono-fluoro analogues were used as test compounds. Remarkable similarities were found between this approach and previously published QSAR studies for hSULT2A1. Both studies implicate the importance of dipole moment and dihedral angle as being important to PCB structure in respect to being substrates for hSULT2A1. We conclude that mono-fluorinated analogues of a target substrate can be a useful tool to study the structure activity relationships for enzyme specificity. 相似文献
546.
A. Franzo R. Auriemma F. Nasi J. Vojvoda A. Pallavicini T. Cibic P. Del Negro 《Environmental science and pollution research international》2016,23(13):12645-12661
The benthic ecosystem functioning is a rarely applied holistic approach that integrates the main chemical and biological features of the benthic domain with the key processes responsible for the flux of energy and C through the system. For the first time, such conceptual model, with an emphasis on the heterotrophic pathways, has been applied to the sediments at four stations within one of the most polluted coastal areas in Italy: the Mar Piccolo of Taranto. The functioning of the benthic ecosystem was different according to the investigated site. Nearby the military arsenal, i.e., the main source of organic contaminants and heavy metals, the system seemed inhibited at all the investigated structural and functional levels. Slow microbial processes of C reworking together with very limited densities of benthic fauna suggested a modest transfer of C both into a solid microbial loop and to the higher trophic levels. On the other hand, the ingression of marine water through the “Navigabile” channel seemed to stimulate the organic matter degradation and, consequently, the proliferation of meiofauna and macrofauna. In the innermost part of the basin, the system functioning, to some extent, is less impacted by contaminants and more influenced by mussel farms. The organic matter produced by these bivalves fueled faster C reworking by benthic prokaryotes and enhanced the proliferation of filter feeders. 相似文献
547.
M. J. Bebianno S. Sroda T. Gomes P. Chan E. Bonnafe H. Budzinski F. Geret 《Environmental science and pollution research international》2016,23(6):5046-5055
The increase use of pharmaceutical compounds in veterinary practice and human population results in the ubiquitous presence of these compounds in aquatic ecosystems. Because pharmaceuticals are highly bioactive, there is concern about their toxicological effects in aquatic organisms. Therefore, the aim of this study was to assess the effects of an effluent from a psychiatric hospital (containing a complex mixture of 25 pharmaceutical compounds from eleven therapeutic classes) on the freshwater clam Corbicula fluminea using a proteomic approach. The exposure of C. fluminea to this complex effluent containing anxiolytics, analgesics, lipid regulators, beta blockers, antidepressants, antiepileptics, antihistamines, antihypertensives, antiplatelets and antiarrhythmics induced protein changes after 1 day of exposure in clam gills and digestive gland more evident in the digestive gland. These changes included increase in the abundance of proteins associated with structural (actin and tubulin), cellular functions (calreticulin, proliferating cell nuclear antigen (PCNA), T complex protein 1 (TCP1)) and metabolism (aldehyde dehydrogenase (ALDH), alcohol dehydrogenase, 6 phosphogluconate dehydrogenase). Results from this study indicate that calreticulin, PCNA, ALDH and alcohol dehydrogenase in the digestive gland and T complex protein 1 (TCP1)) and 6 phosphogluconate dehydrogenase in the gills represent useful biomarkers for the ecotoxicological characterization of psychiatric hospital effluents in this species. 相似文献
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D. L’Hermite E. Vors T. Vercouter G. Moutiers 《Environmental science and pollution research international》2016,23(9):8219-8226
Laser-induced breakdown spectroscopy (LIBS) is a laser-based optical technique particularly suited for in situ surface analysis. A portable LIBS instrument was tested to detect surface chemical contamination by chemical warfare agents (CWAs). Test of detection of surface contamination was carried out in a toxlab facility with four CWAs, sarin (GB), lewisite (L1), mustard gas (HD), and VX, which were deposited on different substrates, wood, concrete, military green paint, gloves, and ceramic. The CWAs were detected by means of the detection of atomic markers (As, P, F, Cl, and S). The LIBS instrument can give a direct response in terms of detection thanks to an integrated interface for non-expert users or so called end-users. We have evaluated the capability of automatic detection of the selected CWAs. The sensitivity of our portable LIBS instrument was confirmed for the detection of a CWA at surface concentrations above 15 μg/cm2. The simultaneous detection of two markers may lead to a decrease of the number of false positive. 相似文献
550.
Scholz C. Jones T. G. West M. Ehbair A. M. S. Dunn C. Freeman C. 《Environmental science and pollution research international》2016,23(18):18192-18199
Environmental Science and Pollution Research - The objective of this study was to monitor a newly constructed wetland (CW) in north Wales, UK, to assess whether it contributes to an improvement in... 相似文献