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41.
Earth observation data processing and storing can be done nowadays only using distributed systems. Experiments dealing with a large amount of data are possible within the timeframe of a lesson and can give trainees the freedom to innovate. Following these trends and ideas, we have built a proof-of-the-concept platform, named GiSHEO, for Earth observation educational tasks. It uses Grid computing technologies to analyze and store remote sensing data, and combines them with eLearning facilities. This paper provides an overview of the GiSHEO's platform architecture and of its technical and innovative solutions.  相似文献   
42.

In the present study, aluminum alloy 7075 (Al7075)-based open-cell silicon carbide (SiC) foam composite was fabricated and the machinability of both Al7075 and the open-cell SiC foam Al metal matrix composite was investigated during milling using an uncoated carbide tool. The machining trials were conducted using the Taguchi L27 full-factorial orthogonal array, and the milling parameters were optimized for surface roughness. Analysis of variance was employed to determine the effect of the cutting variables on surface roughness. The experimental results were evaluated by signal-to-noise ratio, 3D surface graphs, artificial neural networks (ANNs) and main effect graphs. The analysis results show that the feed rate was the most significant milling parameter affecting surface roughness of both Al7075 and the open-cell SiC foam composite. Prediction models have been developed for the surface roughness through regression analysis and ANNs. Confirmation experiments were performed to identify the performance of mathematical models, and the surface roughness was predicted with a mean squared error equal to 1.6 and 0.24 % in the milling of Al7075 and open-cell SiC foam composite, respectively. The test result showed that the three-dimensional open-pore SiC foam network reinforcement was restricted the movement of the soft matrix and provided an acceptable surface quality in the milling of MMCs.

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43.
Yarrowia lipolytica is known to have the ability to assimilate hydrophobic substrates like triglycerides, fats, and oils, and to produce single-cell oils, lipases, and organic acids. The aim of the present study was to investigate the effects of different oil sources (borage, canola, sesame, Echium, and trout oils) and oil industry residues (olive pomace oil, hazelnut oil press cake, and sunflower seed oil cake) on the growth, lipid accumulation, and lipase and citric acid production by Y. lipolytica YB 423-12. The maximum biomass and lipid accumulation were observed with linseed oil. Among the tested oil sources and oil industry residues, hazelnut oil press cake was the best medium for lipase production. The Y. lipolytica YB 423-12 strain produced 12.32 ± 1.54 U/mL (lipase activity) of lipase on hazelnut oil press cake medium supplemented with glucose. The best substrate for citric acid production was found to be borage oil, with an output of 5.34 ± 0.94 g/L. The biotechnological production of valuable metabolites such as single-cell oil, lipase, and citric acid could be achieved by using these wastes and low-cost substrates with this strain. Furthermore, the cost of the bio-process could also be significantly reduced by the utilization of various low-cost raw materials, residues, wastes, and renewable resources as substrates for this yeast.  相似文献   
44.
Food Science and Biotechnology - In this study, lactic acid bacteria diversity during the fermentation of homemade and commercially prepared Tarhana, a traditional fermented cereal food from...  相似文献   
45.
1,2‐Dimethyl‐3‐(5‐methylisoxazol‐3‐yldiazenyl)‐1H‐indole was obtained by coupling 3‐amino‐5‐methylisoxazole with diazotised 1,2‐dimethylindole. It was characterised by proton and carbon nuclear magentic resonance, ultraviolet–visible, infrared and Raman spectra, and the X‐ray single crystal diffraction method. On the theoretical side, the molecular geometry, chemical shifts and the fundamental vibrational frequencies were evaluated using density functional theory. Time‐dependent density functional theory was used to evaluate the electronic excitation spectra. In addition, the scaled quantum mechanical approach was used to study the total energy distributions of the vibrational modes of the molecule. The results showed that the general agreement between experimental and calculated geometric parameters, chemical shifts and λmax values are good. Excellent agreement was found between the calculated and experimental vibrational frequencies.  相似文献   
46.
There is no general rule in the literature to help choose a correct flow control device for any given case of turbomachinery applications. This suggests individual optimization of flow control devices for each specific case. The objective of this study is to prove experimentally the benefits of passive control methods in improving the compressor performance. This allows to reduce the fuel consumption, leading to energy saving and reduction of atmospheric pollution. Two features have been controlled in this study: flow separation over the blade surfaces and the secondary flow over the cascade endwalls. Vortex generator ribs are tested on the blade suction side for flow reattachment on the blade surfaces, and low‐profile vortex generators are tested on the side walls of the compressor cascade against secondary flow losses. Different vortex generator designs are compared for total pressure recovery, flow turning, boundary layer characteristics, and pressure distributions over the endwalls. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
47.
Sea food is a major source of animal protein. Marine foods are very rich sources of mineral components. The total content of minerals in the raw flesh of marine fish and invertebrates is in the range of 0.6–1.5% wet weight. The contents of Na, K, Ca, Mg and P are up to 1 mg/100 g, whereas those of Fe, Zn, I are less than 1 mg/100 g. Mussels (Mytilus galloprovincialis) were investigated for macro and trace element composition throughout the year. Ranges of moisture, ash, protein and fat contents were 79.76–87.46 g/100 g, 1.06–2.06 g/100 g, 7.28–12.65 g/100 g and 0.33–3.49 g/100 g, respectively. While the highest protein and fat values were found in the summer (July–August), the highest moisture and ash contents were found in the winter (December–January). The contents of highest Na, K, Ca were found in the summer. Cadmium, lead and copper were found to be below the legislative limits throughout year. High levels of mercury were found in January and October. It should be discussed whether mussel may provide an alternative source of mineral for healthy nutrition.  相似文献   
48.
49.
Sonication is a well‐known sludge pretreatment technique with the advantages of simple operation and high efficiency. However, it is an energy‐intensive process. Hence, it is very important to predetermine its sludge disintegration efficiency at varying pretreatment conditions in order to minimize the ultrasonic energy consumption. In this study, it was found that the ultrasonic sludge disintegration occurred in two stages: rapid and subsequent slow disintegration stages. For this reason, it was aimed to develop a simple and accurate mathematical model to describe the two‐stage sludge disintegration as a function of pretreatment conditions. Sludge concentration and ultrasonic density along with sonication period were involved in this model as independent variables. It was determined that the mathematical model can predict accurately the degree of sludge disintegration. Thus, the proposed model was seen to be very useful for evaluating the disintegration efficiency and/or for process design using the operating parameters under different conditions.  相似文献   
50.
Novel multifunctional polymer nanofiber electrolytes with covalence crosslinked structures from various solution blends of reactive intercalated poly(vinyl alcohol)/octadecylamine montmorillonite (as a matrix polymer), poly(maleic anhydride‐alt‐methyl vinyl ether) (as a partner polymer) and their NaOH‐absorbing and Ag‐carrying polymer complexes were fabricated via electrospinning. Chemical, physical, morphological, and electrical properties of nanofiber structures were investigated by FTIR, XRD, SEM, and electrical analysis methods. Ag precursors in fiber composites significantly improved phase separation processing, fiber morphologies, diameter distributions, and electrical properties of the fibers. In situ generation of Ag nanoparticles and their distribution on nanofiber surfaces during fiber formation occurred via complex formation between silver cations and electronegative functional groups from both matrix and partner polymers as stabilizing/reducing agents. Electrical resistance and conductivity strongly depended on matrix/partner polymer ratios and absorption time of NaOH solution on nanofibers. Addition of NaOH changed the electrical properties of fiber structures from almost dielectric state to excellent conductivity form. The fabricated unique nanofiber electrolytes are promising candidates for applications in power and fuel cell nanotechnology, electrochemical, and bioengineering processes as reactive semiconductive platforms. POLYM. ENG. SCI., 56:204–213, 2016. © 2015 Society of Plastics Engineers  相似文献   
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