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An evaluation of harvesting costs in present and planned operations: case study—Waston District of Mazandaran Wood and Paper Industries

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Journal of Forestry Research 2018年第1期29卷 215-220页

作者： Majid Lotfalian Mohammad Ali akbari Gorji Seyed Ataollah Hoseini Maryam Kazemi Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Forestry Master of Science Graduates Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Department of Forestry Faculty of Natural ResourcesTehran University

Amongst all forest utilization phases, harvesting plays a key role as the beginning phase of the utilization cycle and has a significant effect on the following *** this research, in order to examine the reduction of costs with respect to present and planned operations, the starting time of the harvesting or cutting phase and work flow were recorded. The starting time of each phase of the entire operation was recorded as well. Before harvesting the marked tree, the appropriate felling direction was determined and the azimuth of the correct direction was *** results indicate that there was not a meaningful relationship between the differences in direction of a leaning tree compared with the felling direction. However, there was a significant relationship between the difference of the defined and felling direction and the difference in tree leaning and defined direction. The same trend was observed between tree leaning and felling directions and tree leaning and defined directions. On the other hand,there was no significant relationship between tree leaning and felling directions and the defined and tree felling directions. In addition, this research shows that with an increase in tree volume, the time for tree cutting ***, when the difference of tree leaning and felling direction decreased, the time to cut the tree *** regression equation is Y = 168.9–0.14（the difference between tree leaning and felling direction）＋ 0.7（volume）.

关键词： Chainsaw Felling direction Cutting time Tree leaning direction

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Wave passage and incoherency effects on seismic response of high arch dams

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 567-578页

作者： H. Mirzabozorg M. akbari M. A. Hariri Ardebili Department of Civil Engineering K.N.Toosi University of Technology

The effects ofincoherency and wave-passage on the nonlinear responses of concrete arch dams are investigated in this study. A double curvature arch dam is selected as a numerical example. The reservoir is modeled as a compressible material and the foundation is modeled as a massless medium. Ground motion time-histories are artificially generated using the Monte Carlo simulation approach. Four different finite element models （FEM） are considered： uniform excitation; incoherence effect; wave passage effect; and both incoherence and wave passage effects. It was revealed that modeling multiple-supports excitation could have a significant impact on the structural response of the dam by inducing a pseudo-static effect. Also, it was concluded that the coherency effect overshadows the wave passage effect and the results obtained from non-uniform excitation of FEM, including the wave passage effect, is close to the results of the FEM when it is uniformly excited.

关键词： concrete arch dam incoherency nonlinear analysis wave passage

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Cube-octameric silsesquioxane (POSS)-capped magnetic iron oxide nanoparticles for the efficient removal of methylene blue

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Frontiers of Chemical Science and Engineering 2019年第3期13卷 563-573页

作者： Ali akbari Nasser Arsalani Bagher Eftekhari-Sis Mojtaba Amini Gholamreza Gohari Esmaiel Jabbari Department of Chemistry Faculty of ScienceUniversity of MaraghehMaraghehIran Research Laboratory of Polymer Department of Organic and BiochemistryFaculty of ChemistryUniversity of TabrizTabrizIran Department of Horticulture Faculty of AgricultureUniversity of MaraghehMaraghehIran Department of Chemical Engineering University of South CarolinaColumbiaSC 29208USA

Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with thioglycolic *** as-prepared Fe3O4@POSS-COOH magnetic hybrid NPs had mesoporous structures with an average particle diameter of 15 nm and a relatively high specific surface area of 447 m^2· g^-*** results showed that 4 mg of Fe3O4@POSS-COOH NPs efficiently adsorbed and removed methylene blue from water at 5 *** is due to the presence of both carboxylic acid and pendant vinyl groups on the Fe3O4@POSS-COOH *** NPs could be easily withdrawn from water within a few seconds under moderate magnetic field and showed high stability in acid and alkaline aqueous mediums.

关键词： nanomagnetic POSS surface polymerization thiol-ene reaction adsorbent water treatment

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Voltammetric determination of isoproterenol using a 5-amino-2',4'-dimethoxybiphenyl-2-ol modified carbon nanotube paste electrode

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Chinese Chemical Letters 2012年第6期23卷 719-722页

作者： Hadi Beitollahi Hoj atollah Khabazzadeh Hassan Karimi-Maleh Ali akbari Environment Department Research Institute of Environmental SciencesInternational Center for ScienceHigh Technology & Environmental SciencesKermanIran Department of Chemistry Shahid Bahonar University of KermanKermanIran Department of Chemistry Science and Research BranchIslamic Azad UniversityMazandaranIran Department of Chemistry University of JiroftJiroftIran

A new electrochemical sensor for determination of isoproterenol （IP） is described. The sensor is based on carbon paste electrode （CPE） modified with 5-amino-2＇,4＇-dimethoxybiphenyl-2-ol （5ADMB） and takes the advantages of carbon nanotubes （CNTs）. Under the optimum pH of 7.0, the oxidation of IP occurs at a potential about 210 mV less positive than that of the unmodified CPE. The oxidation currents increased linearly with two concentration intervals oflP, one is 0.09 to 20.0 μ mol/L and, the other is 20.0 to 400.0 μmol/L. The detection limit （3or） obtained by square wave voltammetry （SWV） was 39.0 μmol/L. The practical application of the modified electrode was demonstrated by determining IP in IP ampoule, urine and human blood serum samples.

关键词： Isoperoterenol Carbon nanotube Electrocatalysis Voltammetry

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Natural convection heat transfer enhancement of different nanofluids by adding dimple fins on a vertical channel wall

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Chinese Journal of Chemical Engineering 2020年第3期28卷 643-659页

作者： Milad Gholami Mohammad Reza Nazari Mohammad Hossien Talebi Farzad Pourfattah Omid Ali akbari Davood Toghraie Department of Mechanical Engineering Yazd UniversityYazdIran School of Mechanical Engineering Science&Arts UniversityYazdIran Mechanical Engineering Department University of Kashan KashanIran Young Researchers and Elite Club Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran

In this numerical study,natural flow and heat transfer of nanofluids with Al2O3,TiO2,Cu and CNT nanoparticles in a vertical channel with dimpled fins at Rayleigh number(Ra)of Ra=3.25×107 to Ra=1×108 are investigated by using the finite volume *** obtained results revealed that,using CNT in volume fractions of 2%and 4%leads to significant heat transfer and atφ=6%,using TiO2 nanoparticles has a great effect on Nu number ***,using solid nanoparticles in base fluid causes more uniform heat transfer distribution,especially in areas close to heated surface and by adding more volume fraction in base fluid,temperature level *** general,according to temperature contours,reduction of wall temperature depends on the increase of Ra and volume fraction and the type of solid nanoparticles.

关键词： Natural heat transfer Dimpled fins Rayleigh number Nanofluid

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Effect of intervention and type of forest management on quality andquantity characteristics of dead wood in managed and reserve forests: Acase study

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Journal of Forestry Research 2012年第3期23卷 413-418页

作者： Kambiz T. Abkenari Fateme akbari Babak Pilehvar Faculty of Natural Resources University of GuilanRashtP. O. BOX:41996-13769Iran Faculty of Agriculture Lorestan UniversityKhoramabadLorestanIran

We compared the dead wood （DW） conditions of Chesh- meh-sar forest and Sardab forest with different management history, including reserve forest and harvested forest. The First forest took 100% inventory from all the available DW. Also dead trees were compared in terms of species, shape, location and quality of fracture in both forests. Volumes of dead wood in Cheshmeh-sar and Sardab forests were 207.47 and 142.74 m3, respectively. Due to this significant difference, impact on the management level was determined. In Cheshmeh-sar forest, 42% of dead trees were standing and 58% were fallen type while in Sardab forest 38.6% were standing and 61.4% fallen. But the difference was not statis- tically significant l^etween them （p = 0.0587）. In terms of quality, dead trees of hard, soft and hollow had the highest frequency, respectively. However, 71.5% of DW was seen as hard dead in Cheshmeh-sar forest while hard dead trees in Sardab forests were 54.2%. Soft quality degree of dead trees which formed in Cheshmeh-sar and Sardab forest were calcu- lated as 26.6% and 43.4% respectively. Also 30% of the dead trees of Sardab forest were eradicated while in Cheshmeh-sar this amount was reduced to 12%. Due to this significant difference （（P=0/018）, it is concluded that the type of management and human interference are affecting the quality of dead trees and makes us to think the human in- terferences could effect on the ecosystem of touched forests.

关键词： dead wood intact forests managed forest reserve forest North of Iran

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A comprehensive study of two-phase flow and heat transfer of water/Ag nanofluid in an elliptical curved minichannel

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Chinese Journal of Chemical Engineering 2020年第2期28卷 383-402页

作者： Sajad Mir Omid Ali akbari Davood Toghraie Ghanbarali Sheikhzadeh Ali Marzban Saeid Mir Pouyan Talebizadehsardari Department of Mechanical Engineering Aligoudarz BranchIslamic Azad UniversityAligoudarzIran Young Researchers and Elite Club Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering University of KashanKashanIran Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam

In this research,laminar flow and heat transfer of two-phase water/Ag nanofluid with 0–6%volume fraction of nanoparticles at Re=150–700 in a curved geometry are simulated using finite volume *** geometry is an elliptical curved minichannel with curvature angle of 180°.Forced and natural flow of two-phase nanofluid is simulated at Gr=15000,35000 and *** estimation of nanofluid flow behavior,two-phase mixture method is *** second-order discretization and SIMPLEC algorithm are used for solving governing *** results indicate that the increase of volume fraction of nanoparticles leads to the enhancement of the temperature of central line of *** increase of Grashof number(Gr^75000)has a great effect on reduction of dimensionless temperature in central line of *** of thermal boundary layer at Re=500 and after the angle of 30°becomes *** low Grashof numbers(Gr^15000),due to the great effects of temperature gradients close to wall,these regions have significant entropy generation.

关键词： Elliptical minichannel Mixed convection Numerical study Nanofluid Finite volume method Friction factor

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An efficient and mild carboxylation of multiwall carbon nanotubes using H_2O_2 in the presence of heteropolyacid

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Chinese Chemical Letters 2012年第4期23卷 470-473页

作者： M.Z.Kassaee H.Zandi J.akbari E.Motamedi Department of Chemistry Tarbiat Modares UniversityP.O.Box 14115-175TehranIran Department of Chemistry Buinzahra BranchIslamic Azad UniversityBuinzahraIran

A clean,fast,and facile oxidation of multiwalled carbon nanotubes（MWCNTs） by H_2O_2/heteropolyacid（H_3PW_（12）O_（40）） gave highly carboxylated MWCNTs under mild conditions,at a conveniently accessible *** an ea... 详细信息

关键词： Nanostructures Oxides Chemical synthesis X-ray diffraction Infrared spectroscopy

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Epidemiological, molecular characterization and risk factors of human brucellosis in Iran

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Asian Pacific Journal of Tropical Medicine 2020年第4期13卷 169-175页

作者： Afshar Etemadi Rezvan Moniri Mahmood Saffari Hossein akbari Saeed Alamian Ali MohammadBehrozikhah Department of Microbiology Faculty of MedicineKashan University of Medical SciencesKashanIran Department of Biostatistics and Public Health Faculty of HealthKashan University of Medical SciencesKashanIranSocial Determinants of Health(SDH)Research CenterKashanIran Brucellosis Department Razi Vaccine and Serum Research InstituteAgricultural ResearchEducation and Extension Organization(AREEO)KarajIran

Objective:To determine epidemiological,molecular characterization,and potential risk factors of human ***:This descriptive study was carried out in the clinical setting in Iran between 2017 and 2018.A total of 297 participants enrolled in the *** sample size was calculated based on the occurrence rate of brucellosis in different *** were assessed using serological tests and conventional culture *** and multiplex PCR methods typed all of Brucella *** risk factors of disease were ***:A total of 141 of 297(47.5%)Brucella strains were isolated and all of them were detected as Brucella melitensis biovar *** on serologic titers,high culture positivity was recorded at 1/640 titer(P<0.006).The risk factors for brucellosis were patients older than 40 years(OR=2.23,95%CI:1.4-3.55,P=0.001),animal keeper(OR=7,95%CI:1.51-32.41,P=0.005),housewife(OR=8.76,95%CI:1.85-41.37,P=0.002),farmer(OR=6.42,95%CI:1.21-33.97,P=0.019),and contact with animal(OR=1.31,95%CI:0.60-2.85,P=0.005).Conclusions:To the best of our knowledge,this is the first comprehensive report from Iran presenting the detection of Brucella species by the multiplex *** melitensis biovar 1 is still the dominant causative agent in *** consumption of unpasteurized dairy products,living in rural areas,and animal contact were risk factors of brucellosis.

关键词： Brucellosis Epidemiology Molecular detection Risk factors

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DETECTING DESERTIFICATION PROCESSES USING TM AND ETM＋ DATA, NORTH OF ISFAHAN, IRAN

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植物生态学报 2008年第2期32卷 328-335页

作者： Khajeddin SJ akbari M Karimzadeh HR Eghbal MK Department of Natural Resources lsfahan University of Technology lsfahan 84156-83111 lran and Department of Agriculture Isfahan University of Technology Isfahan 84156-83111lran

Aims Desertification results in ecological and biological diminution of the earth,and can happen naturally or cause by anthropogenic *** process especially affects arid and semi-arid regions,such as the Isfahan region,where the spread of desertification is reaching critical *** aim of this study is to use remotely sensed data to review the trend of desertification in the northern of Isfahan,*** Multi-temporal images were employed to evaluate the trend of desertification,specifically the TM and ETM+ data of September,1990 and September,*** and radiometric corrections were applied to each image prior to image processing and supervised classification,and vegetation indices were applied to produce a land use map of each image in nine *** land use classifications in the two map images were compared and changes between land use classes were detected over the 11 year period using a fuzzy and post-classification *** findings The maps and their comparison with false color composite images showed the differences *** the fuzzy and post-classification method the land use changes were sited on the *** confirmed 53% changed area and 47% unchanged areas in the study *** results verify the desertification expansion in the study *** of poor land management,agricultural lands converted to desert and abandoned areas,and some marginal pasture lands had to be changed to agricultural land which are desertification spreading according to United Nations Conference on Desertification(UNCOD).Also farmland and pastures have been converted to urban and industrial areas,and the rangelands have been spoiled due to opencast mine *** the mine margins eroding as well as their debris accumulating on the pasture lands,desertification has become *** areas of less-elevated mountains have remained *** study confirmed that the anthropogenic activities accelerated the des

关键词：遥感技术生态环境土壤分级荒漠化

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