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Effects of green iron nanoparticles on iron changes and phytoavailability in a calcareous soil

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Pedosphere 2021年第5期31卷 761-770页

作者： akbar SOLIEMANZADEH Majid FEKRI Department of Soil Science College of AgricultureShahid Bahonar University of KermanKerman ***(Iran)

Green iron nanoparticles(Fe NPs)can be a practical solution to combat iron(Fe)deficiency in calcareous agricultural *** main aim of the present work was to assess the effects of green Fe NPs on Fe availability in calcareous *** this purpose,green Fe NPs were synthesized using green tea(G-Fe NPs),Shirazi thyme(T-Fe NPs),walnut green hull(W-Fe NPs),and pistachio green hull(P-Fe NPs)extracts and applied as a source of Fe fertilizer to sorghum(Sorghum bicolor ***)*** of X-ray diffraction(XRD),scanning electron microscopy(SEM),and dynamic light scattering(DLS)indicated that the green Fe NPs were amorphous in nature and the polyphenols obtained from plant-part extracts acted as both capping and reducing *** to the behavior of Fe-ethylenediamine-N,N-bis(2-hydroxyphenyl)acetic acid(Fe-EDDHA)in calcareous soils,G-Fe NPs,T-Fe NPs,W-Fe NPs,and P-Fe NPs increased Fe release compared with the control and FeSO_(4) *** Fe release data fitted well to the power function,intra-particle diffusion,and Elovich kinetic *** to the pot experiment,the increment in soil Fe availability upon Fe-EDDHA and Fe NPs application led to an increase in Fe uptake,growth,and photosynthetic pigment contents of the sorghum *** further research is needed to evaluate the residual effect and environmental impact of green Fe NPs,they may be an appropriate substitute for traditional Fe fertilizers in calcareous soils.

关键词： chlorophyll content Fe fertilizer Fe release green chemistry natural polyphenols sorghum

GIS based ArcPRZM-3 model for bentazon leaching towards groundwater

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Journal of Environmental Sciences 2010年第12期22卷 1854-1859页

作者： Tahir Ali akbar Henry Lin College of Natural Resources University of Wisconsin-Stevens Point Department of Civil Engineering Schulich School of EngineeringUniversity of Calgary2500 University Drive NWCalgaryAlbertaT2N 1N4Canada Department of Crop and Soil Sciences The Pennsylvania State UniversityUniversity ParkPA 16802USA

Groundwater contamination due to pesticide applications on agricultural lands is of great environmental concern. The mathematical models help to understand the mechanism of pesticide leaching in soils towards groundwater. We developed a user-friendly model called ArcPRZM-3 by integrating widely used Pesticide Root Zone Model version 3 （PRZM-3） using Visual Basic and Geographic Information System （GIS） based Avenue programming. ArcPRZM-3 could be used to simulate pesticide leaching towards groundwater with user-friendly input interfaces coupled with databases of crops, soils and pesticides. The outputs from ArcPRZM-3 could be visualized in user-friendly formats of tables, charts and maps. In this study we evaluated ArcPRZM-3 model by simulating bentazon leaching in soil towards groundwater. ArcPRZM-3 was applied to 37 sites in Woodruff County, Arkansas, USA to observe the daily average dissolved bentazon concentration for soybean, sorghum and rice at a depth of 1.8 m for a period of two years. Nineteen ranks of bentazon leaching potential were obtained using ArcPRZM-3 for all sites having different soil and crop combinations. ArcPRZM-3 simulation results for bentazon were compatible with the field monitored data in term of relative ranking and trend, although some uncertainties exist. This study indicated that macropore flow mechanism would be important in analyzing the effect of irrigation on groundwater contamination due to pesticides. Overall, ArcPRZM-3 could be used to simulate pesticide leaching towards groundwater more efficiently and effectively as compared to PRZM-3.

关键词： ArcPRZM-3 PRZM-3 GIS pesticide leaching groundwater contamination bentazon

An extended iterative direct-forcing immersed boundary method in thermo-fluid problems with Dirichlet or Neumann boundary conditions

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Journal of Central South University 2017年第1期24卷 137-154页

作者： Ali akbar Hosseinjani Ali Ashrafizadeh Faculty of Mechanical Engineering K.N.Toosi University of TechnologyP.O.B.19395-1999 TehranIran

An iterative direct-forcing immersed boundary method is extended and used to solve convection heat transfer *** pressure,momentum source,and heat source at immersed boundary points are calculated simultaneously to achieve the best *** of convection heat transfer problems with both Dirichlet and Neumann boundary conditions are *** approaches for the implementation of Neumann boundary condition,*** and indirect methods,are introduced and compared in terms of accuracy and computational *** test cases include forced convection on a heated cylinder in an unbounded flow field and mixed convection around a circular body in a lid-driven ***,the proposed method is applied to study the mixed convection around a heated rotating cylinder in a square enclosure with both iso-heat flux and iso-thermal boundary *** results show that the order of accuracy of the indirect method is less than the direct ***,the indirect method takes less computational time both in terms of the implementation of the boundary condition and the post processing time required to compute the heat transfer variables such as the Nusselt *** is concluded that the iterative direct-forcing immersed boundary method is a powerful technique for the solution of convection heat transfer problems with stationary/moving boundaries and various boundary conditions.

关键词： immersed boundary method direct forcing thermo-fluid problems neumann boundary condition

A methodological approach to urban landuse change modeling using infill development pattern——a case study in Tabriz, Iran

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Ecological Processes 2016年第1期5卷 1-15页

作者： akbar Rahimi Department of Landscape Engineering University of TabrizBolvare 29 BahmanTabrizIran

Introduction:In recent years,models of land-use change and urban growth have become important tools for city planners,economists,ecologists,and resource *** most models,future land-use changes are forecasted based on past development pattern and expansion to *** today,metropolitan areas employ smart-growth *** main objectives in this study are according to the smart-growth *** this approach,transmission of incompatible land uses to the outside of the city boundary,redevelopment,improvement,and renovation of urban old district and worn-out texture and reuse of abandoned land to new urban development are *** fact,the objective is the using of the infill development pattern to modeling approach for simulating urban future development using potentials inside the ***:This paper presents a Land Transformation Model of urban land-use change based on an artificial neural network and a geographical information *** developing this approach,future development of Tabriz city based on past development trend and infill development pattern is ***:The modeling result based on past development pattern shows that the 31.26% of green spaces and 60.93% of agricultural land and wasteland will be destroyed and the built area will increase 89.75% from 2005 to *** of infill development pattern model can regularize urban expansion in the coming *** result of infill development pattern,show that the built area will increase 40.32 percent and agricultural land and wasteland area decrease 32.67 percent until ***:In fact,redevelopment of urban land uses in infill development pattern until 2021,not only preserve the green spaces and agricultural areas but also improve and rehabilitate old and worn-out textures.

关键词： Land Transformation Model Infill development Urban expansion Sprawl Artificial neural network GIS

Peristaltic flow of Sisko fluid in a uniform inclined tube

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Acta Mechanica Sinica 2010年第5期26卷 675-683页

作者： Sohail Nadeem Noreen Sher akbar Department of Mathematics Quaid-i-Azam University 45320

We have analyzed an incompressible Sisko fluid through an axisymmetric uniform tube with a sinusoidal wave propagating down its walls. The present analysis of non- Newtonian fluid is investigated under the considerations of long wavelength and low Reynolds number approximation. The analytic solution is obtained using （i） the regular perturbation method （ii） the Homotopy analysis method （HAM）. The comparison of both the solutions is presented graphically. The results for the pressure rise, frictional force and pressure gradient have been calculated numerically and the results are studied for various values of the physical parameters of interest, such as α （angle of inclination）, b^＊（Sisko fluid parameter）, Ф （amplitude ratio） and n （power law index）. Trapping phenomena is discussed at the end of the article.

关键词： Peristaltic flow Sisko fluid Perturbation method Homotopy analysis method

Hot Ductility of Severe Plastic Deformed AA6061 Aluminum Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 322-330页

作者： Ali akbar Khamei Kamran Dehghani Mining and Metallurgical Engineering Department Amirkabir University of Technology

The hot ductility of 6061 aluminum alloy,which was subjected to two different severe plastic deformations（SPD）,was studied at different temperatures and strain *** tensile tests were carried out at the temperature range of 300-500 ℃ and at the strain rates of 0.0005-0.01 s^（-1）.The microstructure evolution was characterized using optical microscopy,transmission electron microscopy and X-ray diffraction *** influences of the microstructure after SPD,thermomechanical parameters（temperature and strain rate） and specimen size on the hot formability of this alloy were then *** results show that a decrease in grains/subgrains exhibited significant effect on the hot ductility of SPDed *** constitutive equations were then developed to model the hot formability of the studied *** developed model can be represented by Zener-Hollomon parameter in a hyperbolic sinusoidal equation *** the changes of elongation to failure and Zener-Hollomon parameter indicate that the hot ductility of the alloy is more sensitive to the temperature rather than to the strain *** uniform elongation is independent of the specimen size,but the postnecking elongation increases dramatically as the ratio of l/A^（1/2） decreases.

关键词： Al-Mg-Si alloy Deformation behavior Equal channel angular pressing(ECAP) Rolling Hot tensile deformation

Barley grain for ruminants: A global treasure or tragedy

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Journal of Animal Science and Biotechnology 2012年第4期3卷 167-175页

作者： akbar Nikkhah Department of Animal Sciences Faculty of Agricultural Sciences University of Zanjan

Barley grain （Hordeum vulgate L.） is characterized by a thick fibrous coat, a high level of β-glucans and simply-arranged starch granules. World production of barley is about 30 % of that of corn. In comparison with corn, barley has more protein, methionine, lysine, cysteine and tryptophan. For ruminants, barley is the third most readily degradable cereal behind oats and wheat. Due to its more rapid starch fermentation rate compared with corn, barley also provides a more synchronous release of energy and nitrogen, thereby improving microbial nutrient assimilation. As a result, feeding barley can reduce the need for feeding protected protein sources. However, this benefit is only realized if rumen acidity is maintained within an optimal range （e.g., 〉 5.8 to 6.0）; below this range, microbial maintenance requirements and wastage increase. With a low pH, microbial endotoxines cause pro-inflammatory responses that can weaken immunity and shorten animal longevity. Thus, mismanagement in barley processing and feeding may make a tragedy from this treasure or pearl of cereal grains. Steam-rolling of barley may improve feed efficiency and post-rumen starch digestion. However, it is doubtful if such processing can improve milk production and feed intake. Due to the need to process barley less extensively than other cereals （as long as the pericarp is broken）, consistent and global standards for feeding and processing barley could be feasibly established. In high-starch diets, barley feeding reduces the need for capacious small intestinal starch assimilation, subsequently reducing hindgut starch use and fecal nutrient loss. With its nutritional exclusivities underlined, barley use will be a factual art that can either matchlessly profit or harm rumen microbes, cattle production, farm economics and the environment.

关键词： Barley Cereal Ruminant Starch Treasure

Gauss-Bonnet and Lovelock Gravities and the Generalized Second Law of Thermodynamics

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Chinese Physics Letters 2009年第6期26卷 41-44页

作者： M. akbar Asghar Qadir Centre for Advanced Mathematics and Physics National University of Sciences and Technology Peshawar Road Rawalpindi Pakistan Kavli Institute for Theoretical Physics Chinese Academy of Sciences Beijing 100190

It has been shown [Chin. Phys. Lett.25 （2008） 4199] that the generalized second law of thermodynamics holds in Einstein gravity. Here we extend this procedure for Gauss-Bonnet and Lovelock gravities. It is shown that by employing the general expression for temperature Th =｜κ｜/2π= 1/2πτA （1-τA/2HτA） associated with the apparent horizon of a Friedman Robertson-Walker （FRW） universe and assuming Tm = bTh, we are able to construct conditions for which the generalized second law holds in Gauss Bonnet and Lovelock gravities, where Tm and Th are the temperatures of the source and the horizon respectively.

关键词： No English Keywords

Water-repellent efficiency of thermally modified wood as affected by its permeability

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Journal of Forestry Research 2018年第3期29卷 848-856页

作者： Asghar Tarmian akbar Mastouri Department of Wood and Paper Science and Technology Faculty of Natural Resources College of Agriculture and Natural Resources University of Tehran

This study shows how the air permeability of thermally modified wood contributes to its water-repellent efficiency. For this purpose, freshly cut boards of hornbeam(Carpinus betulus), poplar(Populus nigra), and heartwood of oak(Quercus castanifolia) were modified at a steam temperature of 180 °C for 3 h inside a Thermo Wood *** porous structure, permeability, and water uptake of wood were affected differently by thermal modification,depending on the wood species. The creation of microcracks in the cell walls, due to collapsing of fiber cells,resulted in a noticeable increase in the permeability of hornbeam. Despite checking in the poplar wood structure,its permeability was negatively affected by thermal modification. In contrast to oak and poplar, a negative waterrepellent efficiency was observed for the modified hornbeam, caused by an increase in the permeability.

关键词： Air permeability Thermally modified wood Water-repellent efficiency