Biochemical and molecular characterization of novel PAH-degrading bacteria isolated from polluted soil and sludge

Polycyclic aromatic hydrocarbons (PAHs) containing more than three rings are mainly less biodegradable. Therefore, the isolation of PAHs-degrading bacteria is of great importance to be augmented for bioremediation of polluted sites with PAHs. PAHs-degrading bacteria were isolated from contaminated sites of an oil refinery. The strains were confirmed by biochemical tests and 16S rRNA, which were Stenotrophomonas maltophilia (two strains), Thermomonas koreensis (three strains), Achromobacter (two strains), Pseudomonas stutzeri (one strain), Azospirillum brasilense (one strain) and Brevibacillus brevis (one strain). The isolate strains can be applied as a bacterial consortium for purification of polluted soil with high levels of PAHs.     

Multi-objective algorithms for the application mapping problem in heterogeneous multiprocessor embedded system design

The Journal of Supercomputing - Design at the Electronic System-Level tackles the increasing complexity of embedded systems by raising the level of abstraction in system specification and modeling....     

Flow separation control in open-channel bends

The investigation of fluid flow in sharp open-channel bends is key to controlling undesired sedimentation in natural river reaches. The difficulties are associated with controlling the flow separation in meanderings. Flow separation decreases the width of the flow, and consequently, the conveyance capacity while increasing erosion and mixing. This study proposes a novel approach to reduce the flow separation at the inner banks of sharp open-channel bends. Three-dimensional numerical experiments were conducted. To find the most reliable procedure, five turbulence models were examined. The employed numerical approach is formulated within the framework of the finite volume method and the volume of fluid (VOF) technique to solve the Navier–Stokes equations. Water levels and velocity profiles are obtained in different sections of the channel and are compared to experimental studies of a 90° sharp open-channel bend. A close agreement is observed using the RSM (Reynolds stress model) turbulence model. Moreover, the evaluation of acquired velocity profiles demonstrates that in a regular bend, the lowest velocity occurs near the inner bank, where it has a flow separation tendency. The same numerical procedure is employed to simulate water flow through a sharp converging open-channel bend. The measurements of velocity profiles and velocity vectors in the curved sections support the idea that decreasing the channel width considerably reduces the overall velocity variations in cross-sectional areas of the test case and is effective to control flow separation.     

Thermal effects on the enhanced ductility in non-monotonic uniaxial tension of DP780 steel sheet

To understand the material behavior during non-monotonic loading, uniaxial tension tests were conducted in three modes, namely, the monotonic loading, loading with periodic relaxation and periodic loading-unloadingreloading, at different strain rates (0.001/s to 0.01/s). In this study, the temperature gradient developing during each test and its contribution to increasing the apparent ductility of DP780 steel sheets were considered. In order to assess the influence of temperature, isothermal uniaxial tension tests were also performed at three temperatures (298 K, 313 K and 328 K (25 °C, 40 °C and 55 °C)). A digital image correlation system coupled with an infrared thermography was used in the experiments. The results show that the non-monotonic loading modes increased the apparent ductility of the specimens. It was observed that compared with the monotonic loading, the temperature gradient became more uniform when a non-monotonic loading was applied.     

等径角挤压铜合金的分节断裂

本研究提供了等径角挤压不同铜合金的局部剪切、坯锭开裂和分节断裂的实验依据。结果表明,尽管很多参数影响局部剪切,但是合金的硬度和分节断裂与其有着直接的关系,而硬度与合金的成分和相组成有关。在室温下,α-黄铜可以成功进行等径角挤压,而α/β黄铜甚至在350°C下都不能成功进行等径角挤压。利用DEFORMTM 软件模拟了开裂和分节断裂,研究不同参数对分节断裂的影响。结果表明,摩擦力和加工速率对获得完美坯锭影响很小,而利用背压可以很好地减小局部剪切、坯锭裂纹、分节断裂和破坏。利用背压能减小流动局部化,当背压由0提高到600 MPa时,可以提高材料流动均匀性并且使坯锭的均匀性提高36.1%。     

Thermal performance and entropy generation for nanofluid jet injection on a ribbed microchannel with oscillating heat flux: Investigation of the first and second laws of thermodynamics

In current numerical study, forced flow and heat transfer of water/NDG (Nitrogen-doped graphene) nanofluid in nanoparticles mass fractions (φ) of 0, 2% and 4% at Reynolds numbers (Re) of 10, 50, 100 and 150 are simulated in steady states. Studied geometry is a two-dimensional microchannel under the influence of nanofluid jet injection. Temperature of inlet fluid equals with T_c=293 K and hot source of microchannel is under the influence of oscillating heat flux. Also, in this research, the effect of the variations of attack angle of triangular rib (15°, 30°, 45° and 60°) on laminar nanofluid flow behavior inside the studied rectangular geometry with the ratio of L/H=28 and nanofluid jet injection is investigated. Obtained results indicate that the increase of Reynolds number, nanoparticles mass fraction and attack angle of rib leads to the increase of pressure drop. By increasing fluid viscosity, momentum depreciation of fluid in collusion with microchannel surfaces enhances. Also, the increase of attack angle of rib at higher Reynolds numbers has a great effect on this coefficient. At low Reynolds numbers, due to slow motion of fluid, variations of attack angle of rib, especially in angles of 30°, 45° and 60° are almost similar. By increasing fluid velocity, the effect of the variations of attack angle on pressure drop becomes significant and pressure drop figures act differently. In general, by using heat transfer enhancement methods in studied geometry, heat transfer increases almost 25%.     

Studying the in vitro corrosion response of nanostructured TaN coatings in Hank's physiological solution

The goal of this research is to determine the effect of N₂ pressure to argon pressure on the microstructural analysis and corrosion behavior of nanostructured TaN deposited coatings using a reactive DC-magnetron sputtering (RDCMS) technique. The samples coated microstructure was studied by the X-ray diffraction (XRD) and scanning electron microscope (SEM), and elemental distribution was studied using energy-dispersive X-ray spectroscopy (EDS). To investigate the corrosion behavior of nanostructured TaN coatings, the potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) tests were performed in Hank's physiological solution. The results of different tests revealed that the coating with a content of 17.6% P_N2/P_Ar consisted of hexagonal and orthorhombic TaN phases and had denser microstructure and free pores. This coating showed superior corrosion behavior in comparison to the other ones. Also, the corrosion resistance of this coating raised by increasing the time of immersion from 48 to 168 h.     

Application of ANFIS to predict crop yield based on different energy inputs

In this paper, adaptive neuro-fuzzy inference system (ANFIS) was used to predict the grain yield of irrigated wheat in Abyek town of Ghazvin province, Iran. Due to large number of inputs (eight inputs) for ANFIS, the input vector was clustered into two groups and two networks were trained. Inputs for ANFIS 1 were diesel fuel, fertilizer and electricity energies and for ANFIS 2 were human labor, machinery, chemicals, water for irrigation and seed energies. The RMSE and R² values were found 0.013 and 0.996 for ANFIS 1 and 0.018 and 0.992 for ANFIS 2, respectively. These results showed that ANFIS 1 and ANFIS 2 could well predict the yield. Finally, the predicted values of the two networks were used as inputs to the third ANFIS. The results indicated that the energy inputs in ANFIS 1 have a greater impact on the final yield production than other energy inputs. Also, the RMSE and R² values for ANFIS 3 were 0.013 and 0.996, respectively. These results showed that ANFIS 1 and the combined network (ANFIS 3) could both predict the grain yield with good accuracy.