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Magnesium Uptake and Palygorskite Transformation Abilities of Wheat and Oat

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Pedosphere 2012年第6期22卷 834-841页

作者： M.h.salehi L.TAhAMTANI Department of Soil Science College of AgricultureShahrekord UniversityShahrekord(Iran)

Weathering of clay minerals is a source of nutrients to plants. Palygorskite is a Mg-rich fibrous clay mineral that commonly occurs in the soils and sediments of arid regions. Although many studies have examined the environmental conditions required for the formation and stability of palygorskite, information on the transformation of this mineral in the root zone （or rhizosphere） of agricultural crops is limited. This study explored the possibility of palygorskite transformation in the rhizosphere of wheat and oat and compared the ability of these crops to extract structural Mg from palygorskite. The crops were cultivated in pots consisting of a mixture of sand from hamadan region, Iran and Florida palygorskite, irrigated with distilled water, and treated with either complete or Mg-free nutrient solutions. After 100 d, Mg uptake by the crops was measured. Clay-sized particles in each pot were also separated from the sand and were analyzed through X-ray diffraction （XRD）. The X-ray pattern of the particles was compared with that of the pure palygorskite particles （before cultivation）. The results showed that palygorskite could provide sufficient Mg for the growth of wheat in the pots supplied with Mg-free nutrient solution. In spite of the magnesium uptake by both plants from the palygorskite structure, no detectable peaks indicating the transformation of pMygorskite were recognized by XRD. A decrease of 1.05 nm in peak intensity was more obvious for the pots containing palygorskite and irrigated with Mg-free nutrient solution than for the pots irrigated with complete nutrient solution. Although the decrease in peak intensity was greater for oat than wheat, indicating greater palygorskite weathering by oat, Mg uptake by oat was low, as evidenced by the deficiency symptoms observed.

关键词： clay minerals nutrient solution rhizosphere weathering X-ray diffraction

Refining Soil Organic Matter Determination by Loss-on-Ignition

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Pedosphere 2011年第4期21卷 473-482页

作者： M.h.salehi O.hAShEMI BENI h.BEIGI hARChEGANI I.ESFANDIARPOUR BORUJENI h.R.MOTAGhIAN Department of Soil Science College of AgricultureShahrekord University Department of Soil Science College of AgricultureVali-e-Asr University

Wet oxidation procedure,i.e.,Walkley-Black (WB) method,is a routine,relatively accurate,and popular method for the determination of soil organic matter (SOM) but it is time-consuming,costly and also has a high potential to cause environmental pollution because of disposal of chromium and strong acids used in this ***,loss-on-ignition (LOI) procedure,a simple and cheap method for SOM estimation,which also avoids chromic acid wastes,deserves more *** aims of this research were to study the statistical relationships between SOM determined with the LOI (SOMLOI) and WB (SOMWB) methods to compare the spatial variability of SOM in two major plains,Shahrekord and Koohrang plains,of Chaharmahal-va-Bakhtiari Province,*** surface soil samples (0-25 cm) were randomly collected in each plain to determine SOM using the WB method and the LOI procedure at 300,360,400,500 and 550 ℃ for 2 *** samples covered wide ranges of soil texture and calcium carbonate equivalent (CCE).The general linear form of the regression equation was calculated to estimate SOM LOI from SOM obtained by the WB method for both overall samples and individual *** soil samples were also randomly selected to compare the SOM and CCE before and after ignition at each *** accuracy of the continuous maps generated for the LOI and WB methods was considered to determine the accordance of two *** showed a significant positive linear relationship between SOM LOI and SOM *** of determination (R2) of the equations for individual plains were higher than that of the overall *** of determination and line slopes decreased and root mean square error (RMSE) increased with increasing ignition temperature,which may be due to the mineral structural water loss and destruction of carbonates at higher temperatures.A temperature around 360 ℃ was identified as optimum as it burnt most organic carbon,destroyed less inorganic carbon,cau

关键词： calcium carbonate equivalent ignition temperature kriged maps spatial variability wet oxidation

Qualitative Land Suitability Evaluation for Main Irrigated Crops in the Shahrekord Plain, Iran: A Geostatistical Approach Compared with Conventional Method

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Pedosphere 2013年第6期23卷 767-778页

作者： Y.SAFARI I.ESFANDIARPOUR-BOROUJENI A.KAMALI M.h.salehi M.BAGhERI-BODAGhABADI College of Agriculture Vali-e-Asr University of Rafsanjan Department of Soil Science College of AgricultureVali-e-Asr University of Rafsanjan Department of Soil Science College of AgricultureShahrekord University

The purity of soil map units and their quality for various uses like land suitability evaluation are always *** main objective of this study was to compare the precision of qualitative land suitability classification based on geostatistical and conventional soil mapping methods for main irrigated crops in the Shahrekord Plain,Central Iran.A regular grid sampling method consisting 104sample points was designed and soil samples were *** kriged maps were achieved for all studied soil attributes after physico-chemical ***,to combine kriged maps and ecological requirements of the studied crops,a script was designed in ILWIS 3.4 software and consequently,kriged qualitative land suitability maps were *** qualitative land suitability was also mapped based on the representative pedon analysis in each soil map ***,comparison of the conventional and kriged maps was carried out using the statistical method,error *** results showed that the overall accuracies of wheat,sugar beet,potato and alfalfa maps were 39.8%,24.3%,18.7%and 18.6%at subclass category,respectively,whereas these values increased to80.9%,82.3%,23.7%and 82.3%at class level,***,it can be stated that thanks to the relative facility of conventional soil survey compared with geostatistical methods,this method can be expressed as a preferable way for handling a usual land suitability evaluation design;but using soil map units as land suitability delineations may lead to unsatisfactory results in estimation of quantity and type of existing limitations.

关键词： land use planning ordinary kriging representative pedon soil variability

First Principles Studies on the Electronic Structure and Band Structure of Paraelectric SrTiO<sub>3</sub>by Different Approximations

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Journal of Modern Physics 2011年第9期2卷 934-943页

作者： h. salehi 不详

The electronic structure, energy band structure, total density of states (DOS) and electronic density of perovskite SrTiO3 in the cubic phase are calculated by the using full potential-linearized augmented plane wave (FP-LAPW) method in the framework density functional theory (DFT) with the generalized gradient approximation (GGA) by WIEN2k package. The calculated band structure shows a direct band gap of 2.5 eV at the Γ point in the Brillouin *** total DOS is compared with experimental x-ray photoemission spectra. From the DOS analysis, as well as charge-density studies, I have conclude that the bonding between Sr and TiO2 is mainly ionic and that the TiO2 entities bond *** calculated band structure and density of state of SrTiO3 are in good agreement with theoretical and experimental results.

关键词： Electronic Structure SrTiO3 WIEN2k FP-LAPW DFT GGA

Ground states and excitation spectra of baryons in a non-relativistic model with the anharmonic potential

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Chinese Physics C 2013年第11期37卷 1-8页

作者： N.salehi h.hassanabadi A.A.Rajabi Department of Basic Sciences Shahrood Branch Islamic Azad UniversityShahrood Iran Physics Department Shahrood University of Technology P.O.Box ***-316Shahrood Iran

： In this work the mass spectra for some of the baryon resonances of the particle data group with three and four star status are obtained, and a unified description of the ground states and excitation spectra of baryons are provided in the framework of a non-relativistic potential model. For this goal we have analytically solved the radial SchrSdinger equation for three identical interacting particles with the anharmonic potential by using the Ansatz method and then we have calculated the baryon resonances spectrum by using the G/irsey Radicati mass formula （GR） and with generalized Giirsey Radicati mass formula （GGR）. The results of our model show that the calculated masses of baryon resonances by using the generalized Giirsey Radicati mass formula are found to be in good agreement with the tabulations of the Particle Data Group. The overall good description of the spectrum which we obtain shows that our model can also be used to give a fair description of the energies of the excited multiples up to 3 GeV mass and negative-parity resonance. Moreover, we have shown that our model reproduces the position of the Roper resonance of the nucleon.

关键词： baryons resonances spectrum anharmonic potential non-relativistic quark models

Effects of Milling and heat Treatment on the Synthesis of NiTi Powders

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Journal of Wuhan University of Technology(Materials Science) 2017年第5期32卷 1156-1162页

作者： A R Sadeghi h Mostajabodaveh A Babakhani M S Abravi A salehi Materials Research Group Iranian Academic Center for EducationCulture and Research(ACECR)Mashhad BranchP.O.Box 91779-49367MashhadIran Faculty of Metallurgical and Materials Engineering Semnan UniversityP.O.Box 35131-19111SemnanIran Department of Materials and Metallurgical Engineering School of EngineeringFerdowsi University of MashhadP.O.Box 91775-1111MashhadIran

This work reports on the production of Ni-50 at% Ti powders by a planetary ball mill in various times（0.5, 1, 2, 6, 20, 36, 54 and 120 h） and subsequent heat treatment in Ar atmosphere at 820 °C. Study of powders structure after milling and heat treatment was carried out by scanning electron microscopy and X-ray diffractometry. According to the results, after milling for 6 hours NiTi phase formed, and by the milling evolution up to 54 h, it became the dominant phase. It was found that by the milling development, a layer structure in powder particles was formed, also by increasing the milling time a more homogeneous structure was obtained. Amorphous Ni Ti transformed into ordered Ni Ti, Ni_3Ti, NiTi_2 and minor TiO_2 and TiO after heat treatment at 820 °C for 1 h.

关键词： NiTi milling amorphous heat treatment

A new model for calculating the binding energy of the lithium nucleus under the generalized Yukawa potential and hellmann potential

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Chinese Physics C 2015年第6期39卷 34-39页

作者： M.Ghazvini N.salehi h.hassanabadi A.A.Rajabi Department of Physics Shahrood University Department of Basic Sciences Shahrood Branch Islamic Azad University

In this paper, the Schrodinger equation for a 6-body system is studied. We solve this equation for the lithium nucleus by using a supersymmetry method with several specific potentials. These potentials are the Yukawa potential, the generalized Yukawa potential and the hellmann potential. The results of our model for all calculations show that the ground state binding energy of the lithium nucleus with these potentials is very close to that obtained experimentally.

关键词： lithium calculating nucleus normalized invariance exact fitted dimensions searching applying

Modeling the spread of spatio-temporal phenomena through the incorporation of ANFIS and genetically controlled cellular automata: a case study on forest fire

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International Journal of Digital Earth 2013年第1期6卷 51-75页

作者： Mohammad h.Vahidnia Ali A.Alesheikh Saeed Behzadi Sara salehi Geodesy and Geomatics Engineering Department of Geospatial Information SystemK.N.Toosi University of TechnologyTehranIran Faculty of Geodesy and Geomatics Engineering Department of PhotogrammetryK.N.Toosi University of TechnologyTehranIran

Virtual representation and simulation of spatio-temporal phenomena is a promising goal for the production of an advanced digital *** modeling,which is one of the most helpful analyses in the geographic information system(GIS),plays a prominent role in meeting this *** study proposes a new model that considers both aspects of static and dynamic behaviors of spreadable spatio-temporal in cellular automata(CA)***,artificial intelligence tools such as adaptive neuro-fuzzy inference system(ANFIS)and genetic algorithm(GA)were used in accordance with the objectives of knowledge discovery and *** conditions in updating states are considered so traditional CA transition rules can be accompanied with the impact of fuzzy discovered knowledge and the solution of spread *** focused on the estimation of forest fire growth as an important case study for decision makers.A two-dimensional cellular representation of the combustion of heterogeneous fuel types and density on non-flat terrain were successfully linked with dynamic wind and slope *** validation of the simulation on experimental data indicated a relatively realistic head-fire *** investigations showed that the results obtained using the dynamic controlling with GA in the absence of static modeling with ANFIS were unacceptable.

关键词： geographic information system adaptive neuro-fuzzy inference system cellular automata genetic algorithm spatio-temporal spread forest fire digital earth

hydroxyapatite/alumina nanocrystalline composite powders synthesized by sol–gel process for biomedical applications

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 1033-1036页

作者： S.Khors M.h.Fathi S.salehi S.Amirkhanlou Young Researchers and Elite Club Najafabad Branch Islamic Azad University Department of Materials Engineering Isfahan University of Technology German Textile Research Centre North-West (DTNW) University of Duisburg-Essen Young Researchers and Elite Club Behshahr Branch Islamic Azad University

hydroxyapatite/alumina nanocrystalline composite powders needed for various biomedical applications were successfully synthe- sized by sol-gel process. Structural and morphological investigations of the prepared composite powders were performed using X-ray dif- fractometer （XRD）, scanning electron microscopy （SEM）, X＇Pert highScore software, and Clemex Vision image analysis software. The re- suits show that the crystallite size of the obtained composite powders is in the range of 25 to 90 nm. SEM evaluation shows that the obtained composite powders have a porous structure, which is very useful for biomedical applications. The spherical nanoparticles in the range of 60 to 800 nm are embedded in the agglomerated clusters of the prepared composite powders.

关键词： nanocrystalline materials biomaterials hydroxyapatite alumina sol-gel process nanostructures