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Spatial Variability of Soil Organic Carbon in Different Hillslope Positions in Toshan Area, Golestan Province, Iran: Geostatistical Approaches

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Journal of Mountain Science 2015年第6期12卷 1422-1433页

作者： Abolfazl BAMERI Farhad KHORMALI farshad KIANI Amir Ahmad DEHGHANI Dept. of Soil Science Gorgan University of Agricultural Sciences and Natural Resources Dept. of Water Engineering Gorgan University of Agricultural Sciences and Natural Resources

Accessibility to organic carbon(OC) budget is required for sustainable agricultural development and ecosystem preservation and restoration. Using geostatistical models to describe and demonstrate the spatial variability of soil organic carbon(SOC) will lead to a greater understanding of this dynamics. The aim of this paper is to present the relationships between the spatial variability of SOC and the topographic features by using geostatistical methods on a loess mountain-slope in Toshan region, Golestan Province, northern Iran. Hence, 234 soil samples were collected in a regular grid that covered different parts of the slope. The results showed that such factors as silt, clay, saturated moisture content, mean weighted diameter(MWD) and bulk density were all correlated to the OC content in different slope positions, and the spatial variability of SOC more to slope positions and elevations. The coefficient of variation(CV) indicated that the variability of SOC was moderate in different slope positions and for the mountain-slope as a whole. However, the higher variability of SOC(CV = 45.6%) was shown in the back-slope positions. Also, the ordinary cokriging method for clay as covariant gave better results in evaluating SOC for the whole slope with the RMSE value 0.2552 in comparison with the kriging and the inverse distance weighted(IDW) methods. The interpolation map of OC for the slope under investigation showed lowering SOC concentrations versus increasing elevation and slope gradient. The spatial correlation ratio was different between various slope positions and related to the topographic texture.

关键词： Geostatistics Loess Soil organic carbon(SOC) Slope position Spatial heterogeneity Topography

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A Hybrid Encryption Algorithm for Security Enhancement of Wireless Sensor Networks:A Supervisory Approach to Pipelines

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 323-349页

作者： Omid Mahdi Ebadati E. farshad Eshghi Amin Zamani Department of Mathematics and Computer Science Kharazmi UniversityTehranIran Department of Electrical and Computer Engineering Kharazmi UniversityTehranIran

Transmission pipelines are vulnerable to various accidents and acts of ***,a reliable monitoring system is needed to secure the transmission pipelines.A wireless sensor network is a wireless network consisting of distributed devices distributed at various distances,which monitors the physical and environmental conditions using *** sensor networks have many uses,including the built-in sensor on the outside of the pipeline or installed to support bridge structures,robotics,healthcare,environmental monitoring,*** Sensor networks could be used to monitor the temperature,pressure,leak detection and sabotage of transmission *** sensor networks are vulnerable to various *** algorithms have a good role in information security for wireless sensor ***,various types of cryptographic algorithms provide security in networks,but there are still some *** this research,to improve the power of these algorithms,a new hybrid encryption algorithm for monitoring energy transmission lines and increasing the security of wireless sensor networks is *** proposed hybrid encryption algorithm provides the security and timely transmission of data in wireless sensor networks to monitor the transmission *** proposed algorithm fulfills three principles of cryptography:integrity,confidentiality and *** details of the algorithm and basic concepts are presented in such a way that the algorithm can be operational.

关键词： Wireless sensor networks pipeline cryptography cryptography algorithm hybrid cryptography confidentiality integration authentication

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Development and magnetic properties of loess-derived forest soils along a precipitation gradient in northern Iran

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Journal of Mountain Science 2019年第8期16卷 1848-1868页

作者： Masoumeh POURMASOUMI Farhad KHORMALI Shamsollah AYOUBI Martin KEHL farshad KIANI Department of Soil Science Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Soil Science College of AgricultureIsfahan University of Technology84156-83111 IsfahanIran Institute of Geography University of CologneAlbertus-Magnus-PlatzD-50923 CologneGermany

In order to investigate the development of forest soils formed on loess, six representative modern soil pedons were selected along a precipitation gradient extending from eastern Golestan(mean annual precipitation, MAP = 500 mm)to eastern Mazandaran Provinces(MAP = 800 mm).Physiochemical, micromorphological and magnetic properties, as well as clay mineralogy of soils were studied using standard methods. Soils are mainly classified as Alfisols and Mollisols. Downward decalcification and the subsequent clay illuviation were the main criteria of soil development in all study areas. Pedogenic magnetic susceptibility of pedons studied varied systematically across the precipitation gradient in Northern Iran, increasing from 14.66 ×10-8 m3 kg-1 at the eastern part to 83.75 × 10-8 m3 kg-1 at the western margin of this transect. The frequencydependent magnetic susceptibility showed an increasing trend with rainfall as well. The micromorphological study of soils indicated that there is a positive relationship between climate gradient (increasing rainfall) and the micromorphological index of soil development(MISECA). The area and thickness of clay coatings showed an increasing trend with rainfall. Grain size analysis indicates that pedogenic processes are responsible for changing original grain size distribution of loess in our *** correlation achieved among modern soil properties and precipitation could be applied to the buried paleosols in the whole study area to refer degree of paleosol development and to reconstruct the paleoclimate.

关键词： Magnetic properties Soil formation Weathering Precipitation gradient Loess Iran

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Interlayer shear effect on vibrational behavior of bilayer graphene using the molecular mechanics simulation

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Propulsion and Power Research 2016年第3期5卷 250-260页

作者： Mina Mirparizi farshad Shakeri Aski Department of Mechanical Engineering University of YazdYazdIran Department of Mechanical Engineering Shahid Bahonar University of KermanKermanIran

In this article,the interlayer shear effects on vibrational behavior of bilayer graphene(BG)are studied by using the molecular mechanics(MM)*** on mechanical behavior of graphenes has recently attracted because of their excellent *** simulation is exploited for modeling of covalent bond in the plane of graphene layers and they are modeled as space-frame *** interaction between two layers is modeled by Lennard–Jones potential for not only two apposite atoms but also for all adjacent *** frequencies and mode shapes for cantilever and bridged bilayer graphene as well as monolayer graphene(MG)are obtained by a finite element *** show that the interlayer shear interaction has considerable effect on vibrational behavior of BG and increases the natural frequencies,because existence of horizontal forces(shear forces)that prevent the lateral *** can be seen that the interaction between two layers are more considerable in second mode because the curvature and variation of displacement are higher in second *** it can be found that changing of mode shapes has considerable effect on shear interaction.

关键词： Graphene Vibration Molecular mechanics Interlayer interaction Lennard–Jones

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The impact of land afforestation on carbon stocks surrounding Tehran,Iran

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Journal of Forestry Research 2014年第1期25卷 135-141页

作者： Saeid Varamesh Seyyed Mohsen Hosseini farshad Keivan Behjou Ebrahim Fataei Department of Forestry Faculty of Natural ResourcesTarbiat Modares University Department of Environmental engineering Ardabil BranchIslamic Azad University Faculty of Agricultural Technology and Natural Resources University of Mohaghegh Ardabili

The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon sequestration in two 40 year-old stands of plantedCupressus arizonica andFraxinus rotundifolia in degraded lands surrounding Tehran , sampling of above- and below- ground biomass, soil （at two depths of 0-15 and 15-30 cm）, and leaf litter was done by systematic random sampling. The total carbon stocks ofC. arizonica and F. rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1. The aboveground biomass with 233.16（71%） Mg·ha-1 inC. arizonica and 88.16 （58.50%） Mg·ha-1 inF. rotundifolia contributed the most shares to carbon sequestration. The diameter at breast height, total height, basal area, total volume, and biomass ofC. arizonica were significantly （p 〈0.01） higher than those ofF. rotundifolia. Also the depth of 0-30 cm of soil contributed between 18.29 % and 32.15 % of total ecosystem carbon, respectively. The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars, respectively. Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land, the current status quo. These stands can absorb atmospheric CO2at different rates, thus tree species selection and stand development should be considered in planning future afforestation projects.

关键词： carbon sequestration afforestation Cupressus arizonica Fraxinus rotundifolia Tehran.

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Protective effect of Scrophularia striata combined with trehalose and cysteine added to diluents on cryopreservd goat epididymal sperm

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Asian pacific Journal of Reproduction 2022年第2期11卷 93-99页

作者： Zeinab Maleki Abbas farshad Jalal Rostamzadeh Laboratory of Reproduction Biology Department of Animal SciencesFaculty of AgricultureUniversity of KurdistanSanandajKurdistanIran

Objective:To evaluate antioxidant effects of Scrophularia(S.)striata ethanol extract,trehalose and cysteine added to diluents on cryopreserved goat epididymal ***:Motility and standard motion parameters of sperm were assessed by using computer assisted sperm motility analysis *** viability was evaluated by eosin-nigrosin staining ***-osmotic swelling test was used to evaluate membrane *** acid testing was used to measure malondialdehyde(MDA)*** assess DNA fragmentation,sperm chromatin dispersion test was *** Experiment 1,treatments consisting of basal Tris diluent supplemented with 25,50 or 100µg/mL of *** ethanol extract gave the best concentration to the freezing *** 2 was carried out to compare the best concentration of *** ethanol extract(50µg/mL)resulting from the first experiment with 150 mM trehalose and/or 5 mM cysteine alone or in ***:*** ethanol extract(50µg/mL)significantly increased sperm viability,motility and progressive motility and at the same time decreased MDA concentration and DNA fragmentation compared to other treatments(P<0.05).In addition,all treatment groups resulted in viability,membrane health,total motility,progressive motility,curvilinear velocity,straightline velocity higher and MDA lower compared to the control group(P<0.05).Acrosome integrity was significantly higher in 50µg/mL of *** ethanol extract combined with cysteine,trehalose,or cysteine+trehalose groups than those in the control,trehalose,cysteine,and 50µg/mL of *** ethanol extract groups(P<0.05).Regarding DNA,extenders supplemented with 50µg/mL of *** ethanol extract,50µg/mL of *** ethanol extract+trehalose,and 50µg/mL of *** ethanol extract+trehalose+cysteine were superior to other ***:Adding 50µg/mL of *** ethanol extract alone or in combination with trehalose and cysteine can improve the quality of cryoprese

关键词： Scrophularia striata Cysteine Trehalose Oxidative stress Epididymal Sperm Cryopreservation Antioxidants

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A creative method to tune Fe–O interaction in ferrites

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Journal of Advanced Ceramics 2023年第8期12卷 1612-1624页

作者： farshad Farshidfar Arash Fattahi Ralf Brüning Dominic H.Ryan Khashayar Ghandi Department of Chemistry University of GuelphGuelph N1G 2W1Canada Physics Department Mount Allison UniversitySackville E4L 1E6Canada Physics Department McGill UniversityMontreal H3A 2T8Canada

To be able to regulate the anionic oxygen position in ferrites,an original compositing method is developed by introducing a porous p-type phase in the n-type matrix of ferrite spinel semiconductors.A result of this method is the synergetic effect of the enhanced mass and charge transport that impacted the morphology and anionic oxygen position within the MgFe_(2)O_(4) *** hypothesis is that fine tuning of the anionic oxygen position in ferrites allows us to regulate their physicochemical properties significantly,with the implications for diverse *** electron exchange interaction(J)between O-centered and octahedral-occupying iron(Fe)-centered orbitals affected both the electrical and magnetic properties of the matrix significantly,supporting our *** three-dimensional variable range electron hopping is one such effect.

关键词： Fe_(2)O_(4) spinel structural distortion electron hopping

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Soil physical properties degrade further on skid trails in the year following operations

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Journal of Forestry Research 2018年第1期29卷 93-101页

作者： Ramin Naghdi Ahmad Solgi Eric K.Zenner farshad Keivan Behjou Department of Forestry Faculty of Natural Resources University of Guilan Department of Ecosystem Science and Management Penn State UniversityUniversity Park Faculty of Agricultural Technology and Natural Resources University of Mohaghegh Ardabili

Short-term recovery of soil physical properties on skid trails was investigated upon cessation of skidding operations and 1 year later. Bulk density and porosity were assessed at three levels of traffic intensity and two slope gradients. Compared to undisturbed areas, bulk density increased, total porosity and macroporosity decreased, and microporosity increased in the compacted areas immediately after skidding. In all cases, changes were significantly greater when traffic intensity was higher and when slopes were steeper. Surface soil compaction did not show any recovery over the 1-year period, illustrating the persistent effects of compaction on soil structure. In fact, surficial compaction further increased and macroporosity further decreased after 1 year of recovery, compared to immediately after skidding. While these changes may reflect inherent small-scale site variability or differences in soil moisture content at times of sampling, direct negative physical impacts on newly exposed soil（such as by raindrops）, in addition to the loss of organic matter after canopy removal and skidding, likely delayed any physical recovery, particularly on heavily trafficked trails on steeper slopes. These results raise serious concerns about longterm resilience to traffic on forest soils and indicate the necessity to properly retire skid trails to avoid further soil degradation as trails age.

关键词： Compaction Porosity Recovery Skid trail slope Traffic frequency

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Microstructure and mechanical properties of Al-Mg_2Si composite fabricated in-situ by vibrating cooling slope

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Transactions of Nonferrous Metals Society of China 2018年第4期28卷 604-612页

作者： Shaya SAFFARI farshad AKHLAGHI School of Metallurgy and Materials Engineering College of Engineering University of Tehran

An innovative semisolid technique termed as vibrating cooling slope(VCS)has been applied to producing in-situ Al-25%Mg2Si(mass fraction)*** molten Al-16.5Mg-9.4%Si(mass fraction)alloy with 100°C superheat was poured on the surface of an inclined copper plate(set at 45°inclined angle)while it was vibrated at a frequency of 40 Hz and an amplitude of 400μ*** travelling the length of 40 cm on the slope,the resultant semisolid alloy was cast into a steel *** the purpose of comparison,reference composite samples were made by gravity casting(GC)and conventionally still cooling slope casting(CS)methods using the same alloy under identical *** samples were hot extruded at 500°*** was concluded that the size of Mg2Si particles was decreased by about 50%and 70%for the CS and VCS produced samples respectively when compared to that of the GC produced *** of their higher porosity contents,both the as-cast and hot-extruded VCS processed samples exhibited higher hardness,shear yield stress(SYS)and ultimate shear strength(USS)values as compared with their GC produced *** results were attributed to the refined and modified microstructure obtained via this newly developed technique.

关键词： in-situ composite Al-Mg2Si alloy semi-solid processing vibrating cooling slope microstructure shear punch test

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Decellularized peripheral nerve grafts by a modified protocol for repair of rat sciatic nerve injury

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Neural Regeneration Research 2021年第6期16卷 1086-1092页

作者： Arash Zaminy Sara Sayad-Fathi farshad Moharrami Kasmaie Zohreh Jahromi Adib Zendedel Neuroscience Research Center School of MedicineGuilan University of Medical SciencesRashtIran Student Research Committee School of MedicineGuilan University of Medical SciencesRashtIran Institute of Neuroanatomy Faculty of MedicineRheinisch-Westfälische Technische Hochschule(RWTH)Aachen UniversityAachenGermany

Studies have shown that acellular nerve xenografts do not require immunosuppression and use of acellular nerve xenografts for repair of peripheral nerve injury is safe and ***,there is currently no widely accepted standard chemical decellularization *** purpose of this study is to investigate the efficiency of bovine-derived nerves decellularized by the modified Hudson’s protocol in the repair of rat sciatic nerve *** the modified Hudson’s protocol,Triton X-200 was replaced by Triton X-100,and DNase and RNase were used to prepare accelular nerve *** efficiency of bovine-derived nerves decellularized by the modified Hudson’s protocol was tested in vitro by hematoxylin&eosin,Alcian blue,Masson’s trichrome,and Luxol fast blue staining,immunohistochemistry,and biochemical *** decellularization approach excluded cells,myelin,and axons of nerve xenografts,without affecting the organization of nerve *** decellularized nerve xenograft was used to bridge a 7 mm-long sciatic nerve defect to evaluate its efficiency in the repair of peripheral nerve *** 8 weeks after transplantation,sciatic function index in rats subjected to transplantation of acellular nerve xenograft was similar to that in rats undergoing transplantation of nerve *** analysis revealed that there were a large amount of regenerated myelinated axons in acellular nerve xenograft;the number of Schwann cells in the acellular nerve xenograft was similar to that in the nerve *** findings suggest that acellular nerve xenografts prepared by the modified Hudson’s protocol can be used for repair of peripheral nerve *** study was approved by the Research Ethics Committee,Research and Technology Chancellor of Guilan University of Medical Sciences,Iran(approval ***.1395.332)on February 11,2017.

关键词： acellular scaffold axonotmesis bovine crush injury detergent rat sciatic nerve xenograft

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