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Optimal control homotopy perturbation method for cancer model

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International Journal of Biomathematics 2019年第3期12卷 79-90页

作者： Malihe najafi Hadi Basirzadeh Department of Mathematics Faculty of Mathematical Sciences and Computer Shahid Chamran University of Ahvaz Ahvaz Iran

In this paper, we introduced the optimal control homotopy perturbation method (OCHPM) by using the homotopy perturbation method (HPM). Every one, by using of the proposed method, can obtain numerical solutions of mathematical modeling for cancer-immunotherapy. In this paper, in order to prove the preciseness and efficiency of the OCHPM method, we compared the obtained numerical solutions with HPM. The results obtained showed that the OCHPM method is powerful to generate the numerical solutions for some therapeutic models.

关键词： Optimal control homotopy perturbation method cancer immunotherapy epidemic models

Microscopic and macroscopic atomization characteristics of a pressure-swirl atomizer, injecting a viscous fuel oil

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Chinese Journal of Chemical Engineering 2020年第1期28卷 9-22页

作者： Seyed Mohammad Ali najafi Pouria Mikaniki Hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology(IUST)P.O.B.16765-163TehranIran

Combustion of heavy fuels is one of the main sources of greenhouse gases, particulate emissions, ashes, NOxand SOx. Gasification is an advanced and environmentally friendly process that generates combustible and clean gas products such as hydrogen. Some entrained flow gasifiers operate with Heavy Fuel Oil(HFO) feedstock. In this application, HFO atomization is very important in determining the performance and efficiency of the *** atomization characteristics of HFO(Mazut) discharging from a pressure-swirl atomizer(PSA) are studied for different pressures difference(Δp) and temperatures in the atmospheric ambient. The investigated parameters include atomizer mass flow rate( _m), discharge coefficient(CD), spray cone angle(θ), breakup length(Lb), the unstable wavelength of undulations on the liquid sheet(λs), global and local SMD(sauter mean diameter) and size distribution of droplets. The characteristics of Mazut sheet breakup are deduced from the shadowgraph technique. The experiments on Mazut film breakup were compared with the predictions obtained from the liquid film breakup model. Validity of the theory for predicting maximum unstable wavelength was investigated for HFO(as a highly viscous liquid). A modification on the formulation of maximum unstable wavelength was presented for HFO. SMD decreases by getting far from the atomizer. The measurement for SMD and θ were compared with the available correlations. The comparisons of the available correlations with the measurements of SMD andθ show a good agreement for Ballester and Varde correlations, respectively. The results show that the experimental sizing data could be presented by Rosin-Rammler distributions very well at different pressure difference and temperatures.

关键词： Gasifier Heavy fuel oil Atomization Pressure-swirl atomizer Mazut Size distribution Wavelength Viscosity

Market-based coordination of price-responsive demand using Dantzig-Wolfe decomposition method

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Energy and AI 2023年第4期14卷 329-340页

作者： Foad najafi Matthias Fripp Department of Electrical Engineering University of Hawaii at Manoa2540 Dole StreetHonoluluHawaiiUnited States

The increasing penetration of Distributed Generation(DG)and Demand Responsive(DR)loads in power systems has necessitated the development of novel approaches to address the coordination problem of Price Responsive Devices(PRD).These PRDs are treated as self-interested players aiming to optimize their consumption patterns based on prevailing *** this paper,we propose a new algorithm based on the Dantzig-Wolfe(DW)Decomposition method,which tackles the coordination problem of self-interested PRDs in a distributed *** the distributed nature of the DW approach,we model the self-interested algorithms of PRDs as sub-problems within the DW *** coordinator,or grid operator,responsible for collecting the energy consumption information(energy bids)of PRDs,solves the master problem of the DW and determines the price signal *** proposed algorithm exhibits fast convergence as the sub-problems within DW,which could involve a large number of PRDs(potentially millions),can be solved ***,based on the DW theory,if the PRDs’subproblems are convex,reaching the optimal point(equivalent to Nash Equilibrium)is guaranteed within a limited number of *** evaluate the proposed model,we conducted a simulation involving 200 participant households,each equipped with two types of loads:Electric Vehicles(EVs)as examples of inter-ruptible loads,and Electric Water Heaters(EWHs)as examples of Thermostatically Controlled Loads(TCLs).The results demonstrate that when the algorithm converges to the optimal point,both the generation cost and user payment(based on the marginal cost of generation)***,there is a significant reduction in the Peak to Average Ratio(PAR)of the aggregate load.

关键词： Demand-side management(DSM) Distributed optimization Dantzig-Wolfe algorithm Price responsive devices(PRD) Appliance coordination

Forest Road Detection Using LiDAR Data

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Journal of Forestry Research 2014年第4期25卷 975-980页

作者： Zahra Azizi Akbar najafi Saeed Sadeghian Faculty of Natural Resources Tarbiat Modares University P.O. Box:46414–356 Noor IRAN Geomatics College of National Cartographic Center P.O. BOX: 13185-1684 Tehran IRAN

We developed a three-step classification approach for forest road extraction utilizing LiDAR data. The first step employed the IDW method to interpolate LiDAR point data （first and last pulses） to achieve DSM, DTM and DNTM layers （at 1 m resolution）. For this interpolation RMSE was 0.19 m. In the second step, the Support Vector Machine （SVM） was employed to classify the LiDAR data into two classes, road and non-road. For this classification, SVM indicated the merged distance layer with intensity data and yielded better identification of the road position. Assessments of the obtained results showed 63% correctness, 75% completeness and 52% quality of classification. In the next step, road edges were defined in the LiDAR-extracted layers, enabling accu- rate digitizing of the centerline location. More than 95% of the Li- DAR-derived road was digitized within 1.3 m to the field surveyed nor- rnal. The proposed approach can provide thorough and accurate road inventory data to support forest management.

关键词： forest road LiDAR SVM IDW method

Experimental study of a heavy fuel oil atomization by pressure-swirl injector in the application of entrained flow gasifier

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Chinese Journal of Chemical Engineering 2019年第4期27卷 765-771页

作者： Pouria Mikaniki Seyed Mohammad Ali najafi Hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology

The available SMD(Sauter mean diameter) correlations on pressure-swirl injectors predict droplet sizing very different from each other, especially for heavy fuels. Also there was a lack in the literature for comparing available correlations. So an experimental study was conducted on a heavy fuel oil(HFO) spray, Mazut 380. A pressure swirl injector was designed and fabricated. The experiments for Mazut at 40℃ and 80℃ were compared with the results for water, including spray half cone angle, breakup length and mean droplet diameter,at different injection pressures. Lower spray angle, higher breakup length and larger droplets were observed for lower injection pressures and higher liquid viscosity. SMD was about 75 μm for water and about 87 μm for Mazut at 80℃. The results for droplet mean diameter were also compared with correlations from previous studies on pressure swirl atomizers. The SMD results show that for water spray, LISA method was in good agreement,also Babu and Ballester correlations were successful when high viscosity fluid was injected.

关键词： Atomization Pressure-swirl injector Mazut Size distribution Fuel Viscosity

Direct production of hydrogen peroxide over bimetallic CoPd catalysts:Investigation of the effect of Co addition and calcination temperature

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Green Energy & Environment 2023年第1期8卷 246-257页

作者： Hamidreza Nazeri Alireza najafi Chermahini Zahra Mohammadbagheri Mirko Prato Department of Chemistry Isfahan University of Technology84154-83111IsfahanIran Materials Characterization Facility Istituto Italiano di TecnologiaVia Morego 3016163GenovaItaly

A series of CoPd/KIT-6 bimetallic catalysts with various Co:Pd molar ratios at different calcination temperatures were prepared and used for the direct synthesis of H_(2)O_(2) from H_(2) and O_(2).These catalysts were characterized by nitrogen adsorption-desorption,low and wide-angle X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM),scanning electron microscopy(SEM),elemental mapping and energy-dispersive X-ray(EDX)*** was found that the particle size,electronic interactions,morphology,and textural properties of these catalysts as well as their catalytic activity in the reaction of H_(2) with O_(2) were affected by Co addition and different calcination ***,the results showed that while the H_(2)O_(2) selectivity depends on Pd^(2+) species,the H_(2) conversion is related to Pd0 active *** these catalysts,CoPd/KIT-6 calcined at 350℃(CoPd/KIT-350 catalyst)showed the best catalytic activity with 50%of H_(2)O_(2) selectivity and 51%conversion of H_(2).

关键词： Direct synthesis of hydrogen peroxide Co/Pd catalysts Selectivity The oxidation state of Pd Reusability

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic media

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 43-50页

作者： Abbas TEIMOURI Nasrin SOLTANI Alireza najafi CHERMAHINI Department of Chemistry Payame Noor University(PNU)Isfahan 81395-671Iran Department of Chemistry Payame Noor University(PNU)Shahin Shahr BranchIsfahan 83196Iran Department of Chemistry Yasouj UniversityYasouj 75918-74831Iran

Mono and bis-4-methylpiperidiniummethyl urea were synthesized,characterized and used as new corrosion inhibitors of mild steel in the acidic *** effect of two compounds on mild steel surface in the 1 mol·L^(–1 )sulphuric acid has been studied by a series of techniques,such as potentiodynamic polarization,weight loss and quantum chemical calculation *** polarization measurements showed that two inhibitors are mixed *** measurements showed that inhibition efficiencies enhanced with increase of inhibitor *** reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel *** functional(DFT)calculations have been carried out for the title compounds by performing HF and DFT levels of theory using the standard 6-31G*basis set.

关键词： corrosion inhibitors mild steel acidic medium theoretical studies DFT

Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(NIPU)

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Journal of Renewable Materials 2023年第5期11卷 2171-2190页

作者： Saeed Kazemi najafi Farhood najafi Antonio Pizzi Fatemeh Hassani Khorshidi Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyTehranIran LERMAB University of LorraineBlvd des AiguillettesNancyFrance

Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and *** compounds are mainly used as reactants to make other *** biopolymers,lignin is regarded as the base of a new polymer in polyol *** present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the *** this aim,first,lignin was extracted from raw ***,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene *** results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified ***,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR ***,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample.

关键词： Polyol lignin diethylenetriamine ethylenediamine propylene carbonate polyurethanes NIPU

Preparation of 1-amidoalkyl-2-naphthol derivatives using barium phosphate nano-powders

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Chinese Chemical Letters 2016年第1期27卷 119-126页

作者： Hadi Taghrir Majid Ghashang Mohammad najafi Biregan Devartment of Chemistry. Science and Research Branch Islamic Azad University Arak Iran Department of Chemistry Faculty of Sciences Najafabad Branch Islamic Azad University Najafabad Iran

Barium phosphate（Ba_3（PO_4）_2） nano-powder was successfully synthesized via a simple precipitation route without any surfactant. The prepared nano-powder was applied for the facile synthesis of 1-amidoalkyl-2-naph... 详细信息

关键词： Multi-component reaction 1-Amidoalkyl-2-naphthol Barium phosphate(Ba_3(PO_4)_2) 2-Hydroxydibenzofuran