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61.
In recent years, uneven distribution of available water resources as well as increasing water demands and overexploiting the water resources have brought severe need for transferring water from basins having sufficient water to basins facing water shortages. Therefore, optimal allocation of shared water resources in water transfer projects, considering the utilities of different stakeholders, physical limitations of the system and socioeconomic criteria is an important task. In this paper, a new methodology based on crisp and fuzzy Shapley games is developed for optimal allocation of inter-basin water resources. In the proposed methodology, initial water allocations are obtained using an optimization model considering an equity criterion. In the second step, the stakeholders form crisp coalitions to increase the total net benefit of the system as well as their own benefits and a crisp Shapley Value game is used to reallocate the benefits produced in the crisp coalitions. Lastly, to provide maximum total net benefit, fuzzy coalitions are constituted and the participation rates of water users to fuzzy coalitions are optimized. Then, the total net benefit is reallocated to water users in a rational and equitable way using Fuzzy Shapley Value game. The effectiveness of this method is examined by applying it to a large scale case study of water transfer from the Karoon river basin in southern Iran to the Rafsanjan plain in central Iran. 相似文献
62.
Mojtaba Kooshki Hamid Abdollahi Somayyeh Bozorgzadeh Behzad Haghighi 《Electrochimica acta》2011,(24):8618
Three-way data obtained from different pulse heights of differential pulse voltammetry (DPV) was analyzed using multivariate curve resolution by alternating least squares (MCR-ALS) algorithm. Differential pulse voltammograms of tryptophan were recorded at a gold nanoparticles decorated multiwalled carbon nanotube modified glassy carbon electrode (GCE/MWCNTs-nanoAu). The determination of tryptophan was performed even in the presence of unexpected electroactive interference(s). Both the simulated and experimental data were non-bilinear. Therefore a potential shift algorithm was used to correct the observed shift in the data. After correction, the data was augmented and MCR-ALS was applied to the augmented data. A relative error of prediction of less than 8% for the determination of the simulated analyte of interest and tryptophan in synthetic samples indicated that the methodology employing voltammetry and second-order calibration could be applied to complex analytical systems. 相似文献
63.
In this study, segmented polyurethane/clay nanocomposites were prepared via in situ intercalative polymerization of polyether polyol mixed nanoclay with toluene diisocyanate, followed by chain extending with 1,4-butanediol. The reactive prepolymer tended to gel by increasing the clay content from 0.4 to 1.5 wt.%. This unusual phenomenon was found to be caused by a catalytic effect of quaternary ammonium intercalant on the organoclay. The procedure used for intercalated nanocomposites, is confirmed by wide angle X-ray diffraction studies. Thermogravimetric analysis results demonstrated a very good increase in onset degradation temperature by adding only 0.8 wt.% of organoclay. 相似文献
64.
Kave Moloudi Hadi Samadian Mehdi Jaymand Ehsan Khodamoradi Mojtaba HoseiniGhahfarokhi Farshid Fathi 《IET nanobiotechnology / IET》2020,14(5):428
The main focus of the current study is the fabrication of a multifunctional nanohybrid based on graphene oxide (GO)/iron oxide/gold nanoparticles (NPs) as the combinatorial cancer treatment agent. Gold and iron oxide NPs formed on the GONPs via the in situ synthesis approach. The characterisations showed that gold and iron oxide NPs formed onto the GO. Cell toxicity assessment revealed that the fabricated nanohybrid exhibited negligible toxicity against MCF‐7 cells in low doses (<50 ppm). Temperature measurement showed a time and dose‐dependent heat elevation under the interaction of the nanohybrid with the radio frequency (RF) wave. The highest temperature was recorded using 200 ppm concentration nanohybrid during 40 min exposure. The combinatorial treatments demonstrated that the maximum cell death (average of 53%) was induced with the combination of the nanohybrid with RF waves and radiotherapy (RT). The mechanistic study using the flow cytometry technique illustrated that early apoptosis was the main underlying cell death. Moreover, the dose enhancement factor of 1.63 and 2.63 were obtained from RT and RF, respectively. To sum up, the authors’ findings indicated that the prepared nanohybrid could be considered as multifunctional and combinatorial cancer therapy agents.Inspec keywords: radiation therapy, toxicology, gold, biomedical materials, nanofabrication, nanoparticles, iron compounds, cancer, nanomedicine, cellular biophysics, tumours, graphene compounds, biothermicsOther keywords: graphene oxide nanohybrid, combinatorial cancer treatment agent, cell toxicity assessment, MCF‐7 cells, dose‐dependent heat elevation, multifunctional cancer therapy agents, thermoradiotherapy agent, graphene oxide‐iron oxide‐gold nanoparticles, temperature measurement, radiofrequency wave, flow cytometry, time 40.0 min, CO‐FeO‐Au 相似文献
65.
S. Mojtaba Taghizadeh Hamid Mirzadeh Mehdi Barikani Maryam Yousefi 《International Journal of Adhesion and Adhesives》2009,29(3):302-308
In this study, miscibility and tack of blends of poly (vinylpyrrolidone) (PVP)/acrylic pressure-sensitive adhesive (PSA) were evaluated. For this purpose, appropriate amounts of PVP (2–30% w/w) were added to an acrylic PSA to obtain visually homogeneous solution. The resulting solution was evenly applied on a polyethylene terephthalate (PET) film with final specific thicknesses of 10, 40, and 70 μm by using a film applicator and miscibility as well as tack values were evaluated. With the addition of 2% (w/w) PVP the tack value decreased and increased in 5% (w/w) PVP and then continuously decreased up to 30%(w/w). It was found that the tack value was related to miscibility as well as to viscosity and the free functional group such as hydroxyl group of the blend. By the morphological analysis performed through scanning electron microscopy (SEM) and also by the study of thermal analysis using the differential scanning calorimetry (DSC) behavior of blends, it was found that the two distinct phases constituted after adding 5% (w/w) of PVP. This resulted in the acrylic PSA forming the continuous phase, and by increasing the concentration of PVP a dispersed phase was developed. The dispersed phase has a higher viscosity than the continuous phase and therefore cannot wet the adherent and hence result in lowering the tack values. 相似文献
66.
The characterization of sinusoidal signals with time varying amplitude and phase is useful and applicable for many
fields. Therefore several algorithms have been suggested to estimate main aspects of these signals. Within no
standard approach to test the properties of these algorithms, it seems to be helpful to discuss a large class of
algorithms according to their properties. In this paper, six methods of estimating dynamic phasor have been reviewed
and discussed which three of them are based on least square and others are based on Kalman filter. Taylor expansion
is used as a first step and continued with least square or Kalman filter in accordance with the proposal observer of
each method. The theoretical processes of these methods are briefly clarified. The characterizations have been made
by some tests in time and frequency domains. The tests include amplitude step, phase step, frequency step,
frequency response, total vector error, transient monitor, noise, sample number, computation time, harmonic and DC
offset which build a framework to compare the different methods. 相似文献
67.
Zihua Wang Jia Liu Girish M. Kale Mojtaba Ghadiri 《Journal of Materials Science》2014,49(20):7151-7155
The ion-exchange kinetics of Fe2+ cations in aqueous solution with H+ from alginic acid have been analyzed in this study as a function of contact time lengths using inductively coupled plasma-atomic emission spectrometry analysis. The kinetic parameters have been evaluated using pseudo 1st or 2nd order models, and a consistent ion-exchange mechanism is suggested. Furthermore, an insight into the calcination of Fe2+ ion-exchanged alginic acid process has been obtained by using simultaneous thermo-gravimetric analysis coupled with differential scanning calorimetry and high temperature X-ray diffraction. 相似文献
68.
Hossein Mehrara Behrooz Roozbehani Mohammad Reza Shishehsaz Mojtaba Mirdrikvand Saeedeh Imani Moqadam 《Clean Technologies and Environmental Policy》2014,16(1):59-67
This study was done to determine the optimum process conditions for absorption of sulfur dioxide in a mixture of flue gases. Using a selective amine-based absorber; a high amount of SO2 was absorbed in the scrubbing process. The process was designed to reduce the amount of sulfur dioxide. The pilot plant was designed and set up in the Research Center of Petroleum University of Technology, containing absorption and desorption stages. This paper reports an investigation of the effect and optimization of parameters that improve the efficiency of the whole process. The experiments were conducted under varying levels of desorption temperature, pH of the absorber solution, concentration of SO2 inlet gas, and flow rate of the absorbing solution. Using Taguchi experimental design method, the optimum conditions were identified for the absorption process. An efficiency of more than 99 % could be obtained by varying the parameters in which all the released SO2 gas was absorbed from the inlet flue gas; an achievement that is much favorable for industrial purposes. 相似文献
69.
Mohammad Hossein Habibi Mojtaba Nasr-Esfahani Terry A. Egerton 《Journal of Materials Science》2007,42(15):6027-6035
TiO2—methylcellulose (MC) nanocomposite films processed by the sol-gel technique were studied for phocatalytic applications. Precalcined
TiO2 nanopowder was mixed with a sol and heat treated. The sol suspension was prepared by first adding titanium tetra isopropoxide
(Ti(OPr)4 or TTP) to a mixture of ethanol and HCl (molar ratio TTP:HCl:EtOH:H2O = 1:1.1:10:10) and then adding a 2 wt.% solution of methylcellulose (MC). The TiO2 nanopowder was dispersed in the sol and the mixture was deposited on a microscope glass slide by spin coating. Problems of
film inhomogeneity and defects which caused peeling and cracking during calcinations, because of film shrinkage, were overcome
by using MC as a dispersant. Effect of MC on the structure evaluation, crystallization behavior and mechanical integrity with
thermal treatment up to 500 °C are followed by SEM, XRD and scratch test. XRD Scanning electron microscopy (SEM) showed that
the composite films with MC have much rougher surface than films made without MC. Composite films heat treated at approximately
500 °C have the greatest hardness values. For the composite thick film, the minimum load which caused the complete coating
removal was 200 g/mm2, an indication of a strong bond to the substrate. Photocatalytic activities of the composite film were evaluated through
the degradation of a model pollutant, the textile dye, Light Yellow X6G (C.I. Reactive Yellow 2) and were compared with the
activity of (i) a similar composite film without MC, and (ii) a TiO2 nanopowder. The good mechanical integrity make this composite film an interesting candidate for practical catalytic applications. 相似文献
70.
Prediction of geological hazardous zones in front of a tunnel face using TSP-203 and artificial neural networks 总被引:3,自引:0,他引:3
Andisheh Alimoradi Ali Moradzadeh Reza Naderi Mojtaba Zad Salehi Afshin Etemadi 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2008,23(6):711-717
This research aims at improving the methods of prediction of hazardous geotechnical structures in the front of a tunnel face. We propose and showcase our methodology using a case study on a water supply system in Cheshmeh Roozieh, Iran. Geotechnical investigations had previously reported three measurements of the newly established method of TSP-203 (Tunnel Seismic Prediction) along 684 m of the 3200 m long tunnel up to a depth of 600 m. We use the results of TSP-203 in a trained artificial neural network (ANN) to estimate the unknown nonlinear relationships between TSP-203 results and those obtained by the methods of Rock Mass Rating classification (RMR – treated here as real values). Our results show that an appropriately trained neural network can reliably predict the weak geological zones in front of a tunnel face accurately. 相似文献