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Parametric study on the mixed solvent synthesis of ZiF-8 nano- and micro-particles for CO adsorption: A response surface study

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 579-594页

作者： Alireza Hadi Javad Karimi-Sabet abolfazl Dastbaz Department of Chemical Engineering Faculty of EngineeringUniversity of TehranTehranIran Material and Nuclear Fuel Research School(MNFRS) Nuclear Science and Technology Research InstituteTehranIran

The room temperature synthesis of ZiF-8 micro-and nano-particles was investigated using a mixed methanol-water solvent ***-8 particles of good quality and high crystallinity were *** surface methodology was used to determine the effect of the synthesis conditions on the ZiF-8 yield,particle size distribution,and mean particle *** ligand/metal salt molar ratio followed by the amount of sodium formate(the deprotonating agent)and then the amount of water(i.e,the composition of the mixed solvent)respectively had the largest effects on both the ZiF-8 yield and particle *** showed that mixing of solvents with different strengths in producing ZiF-8 crystals is a practical method to size-controlled synthesis of ZiF-8 *** method is more favorable for industrial-scale ZiF-8 synthesis than using excess amounts of ligands or chemical additives(like sodium formate).in addition,ZiF-8 samples with different mean particle sizes(100,500,and 1000 nm)were used for CO adsorption and the mid-sized ZiF-8 particles had the highest adsorption capacity.

关键词： metal organic frameworks zeolitic imidazo-late frameworks ZiF-8 response surface methodology Box Behnken design CO adsorption

Filter Depth and Cofiniteness of Local Cohomology Modules Defined by a Pair of ideals

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Algebra Colloquium 2014年第4期21卷 597-604页

作者： abolfazl Tehranian Atiyeh Pour Eshmanan Talemi Science and Research Branch Islamic Azad University Tehran Iran islamic Azad University Rasht Branch Gilan Iran

Let i, J be ideals of a commutative Noetherian local ring （R, m） and let M be a finite R-module. The f-depth of M with respect to i is the least integer r such that H_i（M） is not Artinian. in this paper we show that inf{f-depth（a, M）丨a ∈ W（i, J）} is the least integer such that the local cohomology module with respect to a pair of ideals i, J is not Artinian. As a consequence, it follows that H_i,J（M） is （i, J）-cofinite for all i 〈 inf{f-depth（a, M）丨a ∈ W（i, J）}. in addition, we show that for a Serre subcategory S, if H_i,J（M） belongs to S for all i 〉 n and if b is an ideal of R such that H^n_i,J（M/bM） belongs to S, then the module H^n_i,J（M）/bH^n_i,J（M） belongs to S.

关键词： Artinian module local cohomology f-depth

Modification of RDX and HMX crystals in procedure of solvent/anti-solvent by statistical methods of Taguchi analysis design and MLR technique

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Defence Technology（防务技术） 2018年第1期14卷 59-63页

作者： Hamid Reza Pouretedal Sajjad Damiri abolfazl Shahsavan Faculty of Applied Chemistry Malek-ashtar University of Technology (MUT)

Many of the physical and functional properties of RDX and HMX explosives are related to the crystalline structure of these materials. Crystalline defects affect the quality of the explosives. Therefore, in order to enhance the quality of these materials, it is necessary to form crystals with the lowest defects. in this research, we report the optimization of recrystallization process of RDX and HMX by statistical techniques. The solvent/anti-solvent procedure was used for recrystallization of HMX and RDX particles. The four parameters of i) ratio of anti-solvent to solvent, ii) ratio of solute to solvent, iii) aging time, and iv)cooling rate of mixture, were optimized by Taguchi analysis design. Taguchi L16 orthogonal array was used with sixteen rows corresponding to the number of tests in four columns at four levels. The apparent density of recrystallized of RDX and HMX particles was considered as the quality characteristic with the concept of "the larger-the-better". The obtained graphs showed that the studied parameters were optimized in ratio 1:1 for anti-solvent to solvent, ratio 0.1 g,m L^(-1) for solute to solvent, aging time of 2 h and cooling rate of 1℃,min^(-1). Also, the correlation between the investigated parameters and apparent density of crystals were studied by multiple linear regressions(MLR) method for obtaining a model of prediction of apparent density. The P-values were indicated that in confidence level of 95%, the null hypothesis is rejected and a meaningful addition is observed in the proposed model.

关键词： HMX RDX Solvent/anti-solvent Taguchi analysis Apparent density

On Felbin-type Fuzzy 2-normed Spacesand its Fuzzy i-topologies

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模糊系统与数学 2012年第1期26卷 12-19页

作者： Mohammad Janfada abolfazl Nezhadali Baghan Department of Pure Mathematics Ferdowsi University of MashhadMashhadIran Faculty of Science Islamic Azad University-Nikshahr BranchIran

in this paper using the concept of Felbin-type fuzzy 2-norm ‖.,.‖ on a vector space,two i-topologies τ‖.,.‖ and τ*‖.,.‖ is *** making our elementary observations on this fuzzy i-topologies,the continuity of vector space operations is discussed and it is proved that the vector space with i-topology τ‖.,.‖ is not i-topological vector space but with τ*‖.,.‖ is i-topological vector *** we study the relationship between this two i-topologies and it is proved that τ*‖.,.‖■τ‖.,.‖.

关键词： Fuzzy Topology Fuzzy 2-norm i-topology Fuzzy itopological Vector Spaces

Mapping desertification potential using life cycle assessment method: a case study in Lorestan Province, iran

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Journal of Arid Land 2019年第5期11卷 652-663页

作者： abolfazl RANJBAR Somayeh HEYDARNEJAD Sayed H MOUSAVi Roohallah MiRZAEi Department of Desert Studies University of KashanKashan ***Iran Department of Geography and Ecotourism University of KashanKashan ***Iran Department of Environmental Sciences University of KashanKashan ***Iran

in recent year,desertification has become one of the most important environmental hazards all over the world,especially in developing countries such as *** the factors impacting on desertification and identifying the regions with high desertification potential are essential to control this phenomenon(i.e.,desertification).The life cycle assessment(LCA)method is essential in assessing the desertification of ecosystems,especially for susceptible ecosystems with high degradation *** aim of the present study was to evaluate the desertification potential of Lorestan Province,iran,based on the LCA *** selected aridity,fire and dust as three indicators of desertification and collected data from 2000 to *** divided the study area into 6 types of ecoregions according to the climate types(arid,semi-arid and dry sub-humid)and dominant species(Quercus brantii and Astragalus adscendens),and calculated the characteristic factor(CF)of each indicator(aridity,fire and dust)by combining the indicator layers and ecoregion layer of the study *** a given ecoregion,the sum of CF values of aridity,dust and fire indicators represents the life cycle inventory(LCi)desertification value(the higher the LCi value,the greater the desertification potential).Then,we obtained the desertification potential map by combining and overlapping the ecoregions and the normalized indicators based on the LCA *** and fire exhibit significant impacts on desertification in the study area compared with *** the study area,semi-arid ecoregion with Quercus brantii as the dominant species is the largest ecoregion,while arid ecoregion with Quercus brantii as the dominant species is the smallest *** ecoregion with Astragalus adscendens as the dominant species(LCi desertification value of 1.99)and dry sub-humid ecoregion with Quercus brantii as the dominant species(LCi desertification value of 0.79)show the highest and lowest desertification potentials,respec

关键词： life cycle assessment characterization factor desertification potential aridity index fire risk dusty days Lorestan Province

An improved Merkle hash tree based secure scheme for bionic underwater acoustic communication

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Frontiers of information Technology & Electronic Engineering 2021年第7期22卷 1010-1019页

作者： Masoud KAVEH abolfazl FALAHATi Department of Electrical Engineering Iran University of Science and TechnologyTehran 13114-16846Iran

Recently,bionic signals have been used to achieve covert underwater acoustic communication(UWAC)with high signal-to-noise ratios(SNRs)over transmission systems.A high SNR allows the attackers to proceed with their mischievous goals and makes transmission systems vulnerable against malicious *** this paper we propose an improved Merkle hash tree based secure scheme that can resist current underwater attacks,i.e.,replay attack,fabricated message attack,message-altering attack,and analyst *** analysis is performed to prove that the proposed scheme can resist these types of *** evaluations show that the proposed scheme can meet UWAC limitations due to its efficiency regarding energy consumption,communication overhead,and computation cost.

关键词： Dolphin whistle improved Merkle hash tree Secure underwater acoustic communication(UWAC)

A Novel Edge-Assisted ioT-ML-Based Smart Healthcare Framework for COViD-19

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2529-2565页

作者： Mahmood Hussain Mir Sanjay Jamwal Ummer iqbal abolfazl Mehbodniya Julian Webber Umar Hafiz Khan Department of Computer Sciences Baba Ghulam Shah Badshah UniversityRajouriJammu&KashmirIndia Department of Computer Sciences National Institute of Electronics and Information TechnologySrinagarJammu&KashmirIndia Department of Electronics and Communication Engineering Kuwait College of Science and TechnologyKuwait City20185145Kuwait Department of Geriatric Medicine Sher-i-Kashmir Institute of Medical SciencesSrinagarJammu&KashmirIndia

The lack of modern technology in healthcare has led to the death of thousands of lives worldwide due to COViD-19 since its *** internet of Things(ioT)along with other technologies like Machine Learning can revolutionize the traditional healthcare *** of reactive healthcare systems,ioT technology combined with machine learning and edge computing can deliver proactive and preventive healthcare *** this study,a novel healthcare edge-assisted framework has been proposed to detect and prognosticate the COViD-19 suspects in the initial phases to stop the transmission of coronavirus *** proposed framework is based on edge computing to provide personalized healthcare facilities with minimal latency,short response time,and optimal energy *** this paper,the COViD-19 primary novel dataset has been used for experimental purposes employing various classification-based machine learning *** proposed models were validated using kcross-validation to ensure the consistency of *** on the experimental results,our proposed models have recorded good accuracies with highest of 97.767%by Support Vector *** to the findings of experiments,the proposed conceptual model will aid in the early detection and prediction of COViD-19 suspects,as well as continuous monitoring of the patient in order to provide emergency care in case of medical volatile situation.

关键词： COViD-19 edge computing framework internet of Things(ioT) machine learning(ML) network symptoms

Cytotoxicity evaluation of extracts and fractions of five marine sponges from the Persian Gulf and HPLC fingerprint analysis of cytotoxic extracts

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Asian Pacific Journal of Tropical Biomedicine 2015年第11期5卷 896-901页

作者： Davood Mahdian Milad iranshahy abolfazl Shakeri Azar Hoseini Hoda Yavari Melika Nazemi Mehrdad iranshahi Department of Pharmacology School of MedicineMashhad University of Medical Sciences Biotechnology Research Center School of PharmacyMashhad University of Medical Sciences Pharmacological Research Center of Medicinal Plants School of MedicineMashhad University of Medical Sciences Persian Gulf and Oman Sea Ecological Research Organization Iranian Fisheries Research Organization

Objective: To screen the cytotoxic effects of some marine sponges extracts on HeLa and PC12 ***: Five marine sponges including ircinia echinata(i. echinata), Dysidea avara,Axinella sinoxea, Haliclona tubifera and Haliclona violacea were collected from the Persian Gulf(Hengam island). The cytotoxic effect of these sponges was evaluated by using MTT assay. The metabolic high performance liquid chromatography fingerprint of i. echinata was also carried out at two wavelengths(254 and 280 nm).Results: Among the sponges tested in this study, the extracts of i. echinata and Dysidea avara possessed the cytotoxic effect on HeLa and PC12 cells. The obtained fractions from high performance liquid chromatography were evaluated for their cytotoxic properties against the cell lines. The isolated fractions did not show significant cytotoxic ***: i. echinata could be considered as a potential extract for *** investigation is needed to determine the accuracy of mechanism.

关键词： Marine sponges Cytotoxicity HeLa PC12 MTT test

Multiple Choice Reading Comprehension Tests and English as a Foreign Language （EFL） Learners Answering Strategies

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Sino-US English Teaching 2015年第6期12卷 410-423页

作者： Kaivan Parhoodeh Mahmoud Rostamy abolfazl Mehry islamic Azad University Gillan-e-Gharb center Gillan-e-Gharb Iran Khatam Ai Anbia University Tehran lran islamic Azad University Takestan Branch Takestan Iran

As far as we are concemed, one of the elements of assessing EFL/ESL （English as a Foreign Language/English as a Second Language） learners＇ language proficiency in institutions and universities in our country ＂lran＂ are multiple-choice reading comprehension tests. We also know that, it comprises one major section of the standard and TOEFL （Test of English as a Foreign Language） tests. Taking into account its importance and the problems which EFL learners have answered them, i get motivated to uncover some of the test-taking strategies which they employ to answer multiple-choice reading comprehension questions when dealing with familiar versus unfamiliar topics. To get a better conclusion, i choose 20 advanced male and female candidates whose English proficiency is at an acceptable level and at least at the same age level, and they major in English language from different colleges and universities. They are given two reading comprehension passages （familiar and unfamiliar）, each one with five final questions and allotted time to answer the questions. Two main instruments in this study are a retrospective think-aloud protocol and a semi-structured interview. The results of the reading comprehension tests and interview part revealed that advanced learners＇ high scores in the familiar topic were not because of their strategy use but because of their high linguistic and background knowledge on the topic. i also concluded that the number, kind, and sequence of strategies employed, were greatly dependent on the degree of testees＇ familiarity on the topic. in other words, test-takers used more strategies to compensate for their lack of linguistic knowledge.

关键词： test-taking strategies reading comprehension strategies multiple-choice items topic familiarity