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991.
Ali Mohammadi Shahin Rafiee Seyed Saeid Mohtasebi Seyed Hashem Mousavi Avval Hamed Rafiee 《Renewable Energy》2011,36(9):2573-2579
In this study, Data Envelopment Analysis approach was used to analyze the energy efficiency of farmers, to find efficient and inefficient ones and to identify the wasteful uses of energy in kiwifruit production. Moreover, the effect of optimization of energy on improvement of input costs and energy indices was investigated. The results revealed that based on variable returns to scale model, 62.79% of growers were efficient, though, based on constant returns to scale model it was just 23.26%. The technical, pure technical and scale efficiencies of farmers were calculated as 0.942, 0.993 and 0.948, respectively. Total optimum energy requirement was found to be 26,604.11 MJ ha?1; showing that 12.17% of input energy could be saved if the farmers follow the results recommended by this study. The contribution of chemical fertilizers input from total saving energy was about 78% which was the highest share. Optimization of energy use improved the energy use efficiency, specific energy and net energy by 13.86%, 12.17% and 22.56%, respectively. The results of economical analysis showed that optimization of energy decreases the total costs of production by 4.91%; and the benefit–cost ratio and productivity increased by 5.15% and 5.19%, respectively. 相似文献
992.
Atefeh Amiri‐Rigi Mohammad A. Mohammadifar Zahra Emam‐Djomeh Mehrdad Mohammadi 《International Journal of Food Science & Technology》2011,46(9):1830-1839
The aim of this study was to optimise the spray‐drying process for low‐phenylalanine (low‐Phe) milk. Influence of inlet air temperature (100, 150 and 200 °C), feed flow rate (5, 10 and 15 mL min?1) and air flow rate (400, 600 and 800 L h?1) on the solubility, yield, water activity and moisture content (MC) of the milk powder were assessed using response surface methodology. The following optimum process parameters were determined: inlet air temperature of 160 °C, feed flow rate of 8 mL min?1 and air flow rate of 400 L h?1. The predicted values for the solubility, yield, water activity and MC were 98.77%, 88.08%, 0.263% and 5.48%, respectively. With the optimum parameters, the experimental values for the solubility, yield, water activity and MC were 97.56 ± 0.03%, 87.00 ± 0.10%, 0.26 ± 0.01% and 5.53 ± 0.08%, respectively. The similarity of the experimental results to the predicted values verified the models. 相似文献
993.
S. M. Sadat Kiai A. R. Zirak M. Elahi S. Adlparvar B. N. Mortazavi A. Safarien S. Farhangi S. Sheibani S. Alhooie M. M. A. Khalaj A. A. Dabirzadeh M. Ruzbehani F. Zahedi 《Journal of Fusion Energy》2010,29(5):412-415
The paper reports on the design and construction of a Paul ion trap as an ion source by using an impact electron ionization technique. Ions are produced in the trap and confined for the specific time which is then extracted and detected by a Faraday cup. Especial electronic configurations are employed between the end caps, ring electrodes, electron gun and a negative voltage for the detector. This configuration allows a constant low level of pure ion source between the pulsed confined ion sources. The present experimental results are based on the production and confinement of Argon ions with good stability and repeatability, but in principle, the technique can be used for various Argon like ions. 相似文献
994.
In this article, considering the most important interactions between the ionized admixture particles and the working plasma
ones, we have analyzed the effect of added gas on the current and confinement time of the pinched plasma in plasma focus devices.
Moreover, we demonstrate how heating and cooling the pinched plasma can be controlled by the increase and decrease on the
percentage of the added particles and by this way the rise in the rate of D–D nuclear reactions is calculated. 相似文献
995.
Ayatollahi Seyed Morteza Moghadam Amir Masoud Eftekhari Hosseini Monireh Sadat 《Multimedia Tools and Applications》2014,72(2):1887-1909
Multimedia Tools and Applications - In this paper, we propose a taxonomy of depth map creation methods which are used in multiview video compression. The focus is on investigation of approaches... 相似文献
996.
Ahmad Gholami Fatemeh Mohammadi Younes Ghasemi Navid Omidifar Alireza Ebrahiminezhad 《IET nanobiotechnology / IET》2020,14(2):155
In modern medicine, major attention has been paid to superparamagnetic iron oxide nanoparticles (SPIONs). Recent studies have shown the antibacterial properties of SPIONs against some Gram‐positive and Gram‐negative bacterial strains. These nanoparticles (NPs) can bind to bacterial membranes via hydrophobic or electrostatic interactions and pass through cell barriers. In this study, the authors evaluated the antibacterial activity of magnetic NPs in comparison with ferrous and ferric ions. The level of reactive oxygen species (ROS) in the treated Staphylococcus aureus and Escherichia coli bacteria were directly measured by fluorometric detection. The results showed that iron ions and SPIONs had significant dependent antimicrobial activities. SPIONs showed greater inhibitory effects than ferrous and ferric ions against the growth of treated bacterial strains under anaerobic conditions, while in aerobic conditions, ferrous showed the strongest antibacterial activity. In anaerobic conditions, they observed the greatest ROS formation and lowest minimum inhibitory concentration in the SPION‐treated group in comparison with the other groups. It seems that the release of iron ions from SPIONs and subsequent activation of ROS pathway are the main antibacterial mechanisms of action. Nevertheless, the greater antibacterial effect of SPIONs in anaerobic conditions represents other mechanisms involved in the antibacterial activity of these NPsInspec keywords: nanomagnetics, antibacterial activity, hydrophobicity, nanoparticles, superparamagnetism, biomedical materials, iron compounds, membranes, nanobiotechnologyOther keywords: ferrous ions, anaerobic conditions, superparamagnetic iron oxide nanoparticles, antibacterial properties, bacterial membranes, electrostatic interactions, bacterial strains, aerobic conditions, SPION‐treated group, antibacterial effect, cell barriers, 2′,7′‐dichlorodihydrofluorescein diacetate, reactive oxygen species, fluorometric detection, Staphylococcus aureus, Escherichia coli 相似文献
997.
Alireza Asle Zaeem S. Mahmood Sadat Kiai Mahmood Sedaghatizade Shirin Adlparvar Shahab Sheibani 《Journal of Fusion Energy》2009,28(3):268-274
Plasma focus devices are characterized by short-lived dense and hot plasma “pinch” due to the radial compression and electromagnetic
acceleration. Through a short period of time, typically a few tens of nanoseconds, the pinched plasma goes through two phases
of compression (thermal) and expansion (non-thermal or beam target) that provide necessary conditions for high nuclear reaction
rates. If appropriate gas admixture at a desirable pressure is used, the processes can generate short-lived radioisotopes
(SLRs) which the level of activities depends on the design and operational parameters. In this paper, the results of simulated
theoretical works of two SLRs such as 10B (d, n) 11C and 14N (d, n) 15O are presented using a Filippov-type plasma focus “Dena” as a breeder with the bank energy ranges from 20 to 90 kJ at the
repetition rates from 1 to 10 Hz. The admixture gas pressure of 10B and 14 N were taken to be approximately 0.05 of initial working pressure at optimum neutron yield regime. The results obtained are
discussed. 相似文献
998.
Effects of high pressure regimes on the thermal mechanism of neutron yield and anisotropy factor with respect to the capacitor
bank energy are presented by using moving boiler model. It is found that at high pressures, the thermal fusion reactions have a considerable effect on the neutron yield and anisotropy
factor. We have compared the manner of the anisotropy in two low and high pressure discharges to investigate different behavior
of the anisotropy factor as a function of bank energy in the difference working regimes of pressure for Dena PF. 相似文献
999.
Ali Salehzadeh Akram Sadat Naeemi Ladan Khaknezhad Zeinab MoradiShoeili Seyed Ataollah Sadat Shandiz 《IET nanobiotechnology / IET》2019,13(7):766
In this work, the authors investigated the apoptotic activities of Fe3 O4 /Ag nanocomposite biosynthesised by Spirulina platensis extract against MCF‐7 (human breast cancer cells). The physico‐chemical properties of prepared Fe3 O4 /Ag nanocomposite were studied by different spectroscopic methods. To evaluate the in vitro cytotoxic effect, MCF‐7 cells were treated with different concentrations of Fe3 O4 /Ag nanocomposite and examined by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐tetrazolium bromide (MTT) assay. Moreover, apoptotic effects were also studied by Hoechst 33258 staining, caspase 3 activation assays, and annexin V‐fluorescein isothiocyanate (FITC) and propidium iodide staining. Microscopic observations of Fe3 O4 /Ag nanocomposites indicated approximately spherical shape and small particles in the size range of about 30–50 nm. The MTT assay result revealed that the Fe3 O4 /Ag nanocomposite causes a dose‐dependent cell proliferation reduction in MCF‐7 cells (IC50 = 135 μg/ml). Regarding to the Annexin V/PI staining result, the increase percentage of apoptotic cells (28.09%) was detected as compared to untreated cells. According to the caspase assay, Fe3 O4 /Ag nanocomposite enhances caspase 3 level. Furthermore, in vitro anti‐cancer activity of the nanocomposite was performed by Hoechst 33258 staining method. The proposed data suggest that Fe3 O4 /Ag nanocomposite may be an effective agent for the inhibition of breast cancer cells at in vitro level.Inspec keywords: nanomedicine, nanocomposites, toxicology, cancer, drug delivery systems, nanofabrication, cellular biophysics, nanoparticlesOther keywords: MCF‐7 cells, 5‐diphenyl‐tetrazolium, apoptotic effects, propidium iodide staining, dose‐dependent cell proliferation reduction, apoptotic cells, untreated cells, nanocomposite, Hoechst 33258 staining method, human breast cancer cells, physico‐chemical properties, spectroscopic methods, in vitro cytotoxic effect, in vitro anticancer activity, biosynthesis, caspase 3 activation assays, annexin V‐fluorescein isothiocyanate, FITC, Fe3 O4 ‐Ag 相似文献
1000.