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Climate Change and Food Price: A Systematic Review and Meta-Analysis of Observational Studies, 1990-2021

American Journal of Climate Change 2022年第2期11卷 103-132页

作者： Ramesh Allipour Birgani Ali Kianirad Sakineh Shab-Bidar abolghasem djazayeri Hamed Pouraram Amirhossein Takian Department of Community Nutrition School of Nutritional Sciences and Dietetics Tehran University of Medical Sciences Tehran Iran Agricultural Planning Economic and Rural Development Researches Institute Tehran Iran Department of Global Health & Public Policy School of Public Health Tehran University of Medical Sciences Tehran Iran Department Health Management Policy & Economics School of Public Health Tehran University of Medical Sciences Tehran Iran Health Equity Research Center (HERC) Tehran University of Medical Sciences Tehran Iran

Climate extreme events have threatened food security and the second Sustainable development goals (SDGs) “zero hunger” both directly via agricultural food loss and indirectly through rising food prices. We systematically searched and used a combination of results from various models, which play a crucial role in predicting the potential impact of climate change on agricultural production and food price. Therefore, we searched online databases including EMBASE, Web of Science, Scopus, Google Scholar, and grey literature. Then observational studies were included from January 1990 to August 2021, which reported food price proportion under climate disturbances. Results showed that 22 out of 26 studies from 615 articles, identified in the meta-analysis predicted the food price ratio would be fluctuated up to 28% before 2020, while the ratio will be marked up at 31% from 2020 to 2049 and then will scale down during 2050-2100. The compiled ratio was estimated at 26% in the long period between 2000 until 2100 under climatic weather events. Drought was a significant weather disturbance with a 32% increase in food prices. Consequently, the Food price increase will significantly affect food accessibility in lower-income countries, primarily until 2050. Policymakers should prioritize and act through redesigning food security policies according to climatic extremes in their settings.

关键词： Climate Change Food Security Food Price Extreme Weather Events Systematic Review

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Characterization of mechanothermally processed nanostructured ZnO

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 588-594页

作者： Saeed Karimi abolghasem Ataie School of Metallurgy and Materials Engineering College of Engineering University of Tehran

In this paper, the Taguchi method with an L9（34） orthogonal array was used as experimental design to determine the optimum conditions for preparing ZnO nanoparticles via a mechanothermal route. ZnSO4·H20 and NaECO3 were used as starting materials. The effects of milling time, NaECO3/ZnSO·H20 molar ratio, and ball-to-powder mass ratio （BPR） on the bandgap （Eg） of ZnO nanoparticles were inves- tigated. The ranges of the investigated experimental conditions were 5-15 h for the milling time （t）, 1.0-1.2 for the Na2COa/ZnSO4·H20 mo- lar ratio （M）, and 10-30 for BPR. The milling time and BPR exhibited significant effects; an increase in milling time reduced the bandgap. The optimum conditions from this study were t3 = 15 h, M1 = l, and BPR2 = 20. Only two significant factors （t3, 15 h; BPR2, 20） were used to estimate the performance at the optimum conditions. The calculated bandgap was 3.12 eV, in reasonable agreement with the experimental results obtained under the optimized conditions.

关键词： mechanothermal treatment synthesis nanoparticles zinc oxide Taguchi methods

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LASIK surgery in patients with residual refractive errors after radial keratotomy

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International Journal of Ophthalmology(English edition) 2010年第2期3卷 172-174页

作者： abolghasem Rastegar Department of Ophthalmology Sadoughi HospitalYazd Medical Sciences UniversityYazdIran

AIMTo study the results and complications of LASIK surgery after radial keratotomy.

关键词： LASIK radial keratotomy refractive surgery residual myopia

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Numerical Investigation of High Pressure and High Reynolds Diffusion Flame Using Large Eddy Simulation

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Journal of Thermal Science 2014年第5期23卷 412-421页

作者： Ali Lohrasbi Nichkoohi abolghasem Mesgarpour Tousi Department of Aerospace Engineering-Amirkabir University of Technology-Center of Excellence in Computational Aerospace Engineering-Tehran-Iran

Today,with nonstop improvement in computational power,Large-Eddy Simulation(LES) is a high demanding research tool for predicting engineering *** flows on high pressure condition like diesel engines is extensively employed in ground and marine transportation,oblige the designer to control and predict toxic pollutants,while maintaining or improving their high thermal *** becomes one of the main challenging issues in *** the present work,numerical investigation of diffusion flame dynamics is performed in the near-field of high-Reynolds jet flow on high pressure condition encountered in diesel engine *** work discusses the implementation of Partially Stirred Reactor(PaSR) combustion model by the approaches of large eddy simulation(LES).The simulation results show that LES,in comparison with Reynolds-Averaged Navier-Stokes(RANS) simulation predicts and captures transient phenomena very *** phenomena such as unsteadiness and curvature are inherent in the near-field of high Reynolds diffusion *** outcomes of this research are compared and validated by other researchers' *** comparisons of the statistics show good agreement with the corresponding experiments.

关键词： large eddy simulation-non premixed combustion-flame dynamics-diffusion flame-high Reynolds flow-diesel engine

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Ti leaching from activated ilmenite–Fe mixture at different milling energy levels

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1263-1274页

作者： Elham Hosseini Fereshteh Rashchi abolghasem Ataie School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran

Mechanical activation processes on ilmenite concentrate were performed in three different energy levels. Iron powder as a reducing agent was added to ilmenite in the milling stage and the mechanically activated mixture was subjected to acid leaching. The leaching experiments were designed using the Taguchi method, and the optimum ranges were obtained. Furthermore, response surface methodology(RSM) was used to optimize the critical parameters in the leaching system to achieve the highest titanium(Ti) leachability. Based on the inductively coupled plasma-optical emission spectrometry(ICP-OES) results, maximum leaching recovery of Ti(80%) was obtained using activated Ti concentrates at a medium activation energy level, which is calculated to be 25.38 kJ/g, using 15 vol% hydrochloric acid(HCl), a temperature of 70°C, leaching time of 3 h, and a solid-to-liquid ratio of 0.05 g×mL^(–1). Intensifying the milling energy from a low to high level led to a decrease in the mean crystallite size and also structure homogenization at the high energy level. According to the transmission electron microscopy(TEM) images, the mean grain size of the ilmenite/Fe nanocomposite was about 30 nm at the medium energy level sample. Finally, solvent extraction by tributyl phosphate(TBP) was performed on the leach liquor to separate dissolved Fe(the major impurity) from Ti, which led to 83% extraction recovery of Ti.

关键词： ilmenite leaching titanium extraction mechanical activation

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Application of Froude dynamic similitude in anaerobic baffled reactors to prediction of hydrodynamic characteristics of a prototype reactorusing a model reactor

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Water Science and Engineering 2017年第1期10卷 53-58页

作者： Mehdi Hassanvand Jamadi abolghasem Alighardashi Faculty of Civil Water and Environmental EngineeringShahid Beheshti UniversityTehran ***Iran

An anaerobic baffled reactor is a system developed in recent decades and has been used as part of the treatment of high-strength wastewater. Since the function of this system is based on its hydrodynamic features, hydrodynamics and the regime of the flow through the reactor are crucial. In this study, a prototype reactor with eight chambers, which had a total volume of 48 L, and a model reactor, whose dimensions were half of those of the prototype reactor, were used. The Froude dynamic similitude in these reactors was investigated. The results show that the curve dimensionless variances were 0.089 and 0.096 for the prototype and model reactors, respectively, the short-circuiting indices were 0.483 and 0.489 for the prototype and model reactors, respectively, the effective volume and short-circuiting index measurement errors were both 1%, the hydraulic efficiency error was 2%, and the Peclet and dispersion number errors were both 7%. Most of the compared indices were close to one another in value. Therefore, the model reactor can be used based on the Froude dynamic similitude to determine hydrodynamic charac-teristics of a baffled reactor at a full scale.

关键词： Anaerobic baffled reactor Froude dynamic similitude Hydrodynamics Prototype reactor Dead space

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Characterization of B site codoped LaFeO_3 nanoparticles prepared via co-precipitation route

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Rare Metals 2018年第3期37卷 181-190页

作者： Seyedeh Behnaz Varandili Alireza Babaei abolghasem Ataie School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran

LaFe（1-x-y）CoxPdyO3 [（x, y） =（0, 0）,（0.40, 0）,（0.38, 0.05）] nanoparticles were synthesized via a co-precipitation route using ammonium hydroxide, sodium hydroxide and ammonium carbonate as the precipitant and calcination at different temperatures to study the compositional driven structural changes in lanthanum *** of X-ray diffraction（XRD） patterns confirms the formation of single-phase perovskite structure and existence of orthorhombic Pnma symmetry for calcined powders. Field emission scanning electron microscope（FESEM） observations show that Pd-doped powders yield finer particles along with narrower particle size distribution compared with LaFeO3 and LaFe（0.6）Co（0.4）O3. Moreover,using ammonia as the precipitant leads to a smaller mean particle size of powders compared to NaOH, as well as significant difference in morphology of the *** analysis reveals that both Co and Pd atoms substitute Fe site in perovskite structure with shifting of phonon modes. Comparing Raman spectra demonstrates the presence of more oxygen vacancies in Pd-doped perovskites. It can be concluded from the results that Pd is successfully incorporated into the perovskite structure by co-precipitation method.

关键词： Perovskites Pd doping Nanoparticles Co-precipitation Raman spectroscopy

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Split vector quantization for sinusoidal amplitude and frequency

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 140-154页

作者： Pejman MOWLAEE abolghasem SAYADIAN Hamid SHEIKHZADEH Department of Electronic Engineering Amirkabir University of Technology

In this paper, we suggest applying tree structure on the sinusoidal parameters. The suggested sinusoidal coder is targeted to find the coded sinusoidal parameters obtained by minimizing a likelihood function in a least square (LS) sense. From a rate-distortion standpoint, we address the problem of how to allocate available bits among different frequency bands to code sinusoids at each frame. For further analyzing the quantization behavior of the proposed method, we assess the quantization performance with respect to other methods: the short-time Fourier transform (STFT) based coder commonly used for speech enhancement or separation, and the line spectral frequency (LSF) coder used in speech coding. Through extensive simulations, we show that the proposed quantizer leads to less spectral distortion as well as higher perceived quality for the re-synthesized signals based on the coded parameters in a model-based approach with respect to previous STFT-based methods. The proposed method lowers the complexity, and, due to its tree-structure, leads to a rapid search capability. It provides flexibility for use in many speaker-independent applications by finding the most likely frequency vectors selected from a list of frequency candidates. Therefore, the proposed quantizer can be considered an attractive candidate for model-based speech applications in both speaker-dependent and speaker-independent scenarios.

关键词： Short-time Fourier transform Split vector quantization Sinusoidal modeling Spectral distortion

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A Carbon Material as a Strong Protonic Acid for Efficient Synthesis of 4（3H）-Quinazolinones

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Chinese Journal of Chemistry 2011年第8期29卷 1685-1688页

作者： Tavakoli-Hoseini, Niloofart Davoodnia, abolghasem Department of Chemistry Mashhad Branch Islamic Azad University Mashhad Iran

Carbon-based solid acid catalyst has been applied to catalyzing the synthesis of 4（3H）-quinazolinones from the cyclization reaction of 2-aminobenzamide with aroyl chlorides. The results showed that the catalyst was very efficient with the average yield over 85%. This carbon material with strong protonic acid sites as heterogeneous cata- lyst has some advantages such as high activity, strikingly simple work-up procedure, non-pollution, and reusability, which will contribute to the green process greatly.

关键词： carbon-based solid acid heterogeneous catalysis 2-aminobenzamide aroyl chlorides cyclization

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On the rate of complete convergence for weighted sums of NSD random variables and an application

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Applied Mathematics(A Journal of Chinese Universities) 2017年第3期32卷 270-280页

作者： NADERI Habib AMINI Mohammad BOZORGNIA abolghasem Department of Statistics Faculty of Mathematical Sciences Ferdowsi University of Mashhad MashhadIran Department of Statistics Faculty of Mathematical Sciences University of Sistan and BaluchestanZahedan Iran Department of Statistics Khayyam University Mashhad Iran

In this paper, the complete convergence is established for the weighted sums of negatively superadditive-dependent random variables. As an application, the Marcinkiewicz-Zygmund strong law of large numbers for the random weighted average is also achieved, and a simulation study is done for the asymptotic behaviour of random weighting estimator.

关键词： complete convergence negatively superadditive-dependent random weighted estimate

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