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Assessment of Agricultural Soil Quality Indices Using Mechanistic Models

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Open Journal of Soil Science 2024年第6期14卷 333-352页

作者： Mohammadali Nikpey Javad Robatjazi Shahabeddin Garmehei Hendra Gonsalve W. Lasar Nguyen Khoi Nghia Benjamin Kwadwo Agyei Department of Soil Science Faculty of Agriculture Tarbiat Modarres University Tehran Iran Texas A&M AgriLife Research Department of Soil and Crop Sciences Texas A&M University College Station TX USA Faculty of Soil Sciences College of Agriculture Can Tho University Can Tho Vietnam Department of Plant Soil and Microbial Sciences Michigan State University East Lansing MI USA

Assessing soil quality is a critical strategy for diagnosing soil status and anticipating concerns in land use systems for agricultural sustainability. In this study, two soil quality assessment indices, the Integrated Quality Index (IQI) and Nemoro Quality Index (NQI), were employed using two indicator selection methods: Total Data Set (TDS) and Minimum Data Set (MDS), focusing on agricultural fields in Golestan province, Iran. A total of 89 soil samples were collected and analyzed for particle size distribution, organic carbon, calcium carbonate equivalent (CCE), electrical conductivity (EC), pH, and plant-essential nutrients, including nitrogen, phosphorus, potassium, zinc, copper, manganese, and iron. Principal component analysis (PCA) was used to extract MDS from TDS, and geostatistical adaptation and correlation analyses were performed to determine the optimal soil quality evaluation index. Our results show that the exponential model better suits the spatial structure of soil quality indicators (IQIMDS: 0.955). Conformity and correlation analyses indicate that the IQI index outperformed the NQI index in estimating soil quality. The superiority of the TDS technique over the MDS technique in terms of accuracy (IQITDSs kappa: 0.155). Linear relationships between different methods showed a higher correlation coefficient (R2 = 0.43) through the application of IQI. This study suggests the use of IQIMDS to provide a reliable measurement that is particularly useful in assessing the quality of agricultural soil.

关键词： Soil Quality Geographic Information System Integrated Quality Index Nemoro Quality Index

Effect of Strain Rate on the Ferrite Grain Refinement in a Low Carbon Nb-Ti Microalloyed Steel during Low Temperature Deformation

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Journal of Materials Science & Technology 2005年第6期21卷 851-855页

作者： B.Eghbali A.Abdollah-zadeh Department of Materials Engineering Tarbiat Modarres University P.O. Box 14115-143 Tehran Iran

Grain refinement is one of the effective methods to develop new generation low carbon microalloyed steels possessing excellent combination of mechanical properties. The microstructural evolution and ferrite grain refinement at the deformation temperature of 865℃, above Ar3, with different strain rates were investigated using single pass isothermal hot compression experiments for a low carbon Nb-Ti microalloyed steel. The physical processes that occurred during deformation were discussed by observing the optical microstructure and analyzing the true stress-true strain responses. At strain rates of 0.001 and 0.01s^-1, there is no evidence of work hardening behavior during hot deformation and strain-induced transformation （SIT） leads to dynamic flow softening in flow curves. Optical microscopy observation shows that ultrafine and equiaxed ferrite with grain sizes of 2μm can be obtained by applying deformation with strain rate of 0.1 s^-1 due to SIT just after deformation. Furthermore, increasing the strain rate from 0.001 to 0.1 s^-1 reduces both the grain size of the equiaxed ferrite and the amount of deformed ferrite.

关键词： Low carbon microalloyed steel Hot compression Grain refinement Strain induced transformation

EXPERIMENTAL AND FIELD STUDY ON MINING-PIT MIGRATION

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International Journal of Sediment Research 2002年第4期17卷 323-331页

作者： S.Ali Akbar Salehi NEYSHABOURI,Ali FARHADZADEH,Ata AMINI Civil Engineering Dept. University of tarbiat modarres University of tarbiat modarres University of tarbiat modarres Assistant Professor P.O.Box14115-143 Tehran Iran Ph.D.Student Msc.Student

Rivers are one of the most essential sources of sand and gravel supply for civil works. However, undesirable effects of irregular in-stream mining have been reported on natural sources, environment and infrastructures close to rivers. Therefore, it is necessary to find the effects of mining on rivers in more details. This research concentrates on mining-pit migration phenomenon and its effects on the channel bed. This paper reports an experimental study on the migration of rectangular mining pits and variation of longitudinal profile in the channel bed composed of rather uniform sediments. Different values of widths and lengths were used for pit while pit depths and flow variables were kept constant. The results show that the migration speed changes with the length/width ratio of the pit. The migration speed in convection period is higher than that in diffusion period. In addition, by increasing the length or width, filling rate of pit increases, where the effect of width is more important than the effect of the length. Also is reported in this paper a field study on the changes of three pits excavated at different locations of a river. Some similarities between the pit migration in the straight reach of the river and that of the experimental work is realized and presented.

关键词： Pit migration Sand and gravel mining Experiment Field study

利用核函数法中的自适应带宽同时对一维空间两个储集层属性参数进行粗化

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石油勘探与开发 2019年第4期46卷 710-715页

作者： MOHAMMAD Reza Azad ABOLGHASEM Kamkar Rouhani BEHZAD Tokhmechi MOHAMMAD Arashi EHSAN Baratnezhad Shahrood University of Technology Shahrood ***Iran tarbiat modarres Tehran 114-14115Iran

在多孔介质流体流动模拟中,应用网格粗化方法必须在保留重要储集层参数的空间分布的前提下,首先利用大网格粗化原始地质模型(尤其是孔隙型介质),并用数值方法求解。提出了根据属性参数的空间分布、以核函数的自适应带宽为基础的网格粗... 详细信息

在多孔介质流体流动模拟中,应用网格粗化方法必须在保留重要储集层参数的空间分布的前提下,首先利用大网格粗化原始地质模型(尤其是孔隙型介质),并用数值方法求解。提出了根据属性参数的空间分布、以核函数的自适应带宽为基础的网格粗化新方法,该方法既减少了网格数量,同时也保留原始精细模型的主要非均质性特征。该方法的关键点在于可以同时对两种储集层属性参数进行网格粗化。首先计算每个储集层属性参数的带宽量或最优门槛值并得到粗化结果,然后根据最大带宽和最小带宽采用两种不同的方法对两个属性参数同时粗化。现在已经能够实现利用不同方法建立储集层两个属性参数的最终粗化模型,不同方法的网格单元数和网格位置都相同。最小带宽法的粗化误差小于最大带宽法。

关键词：储集层属性同步粗化原始模型模拟模型自适应带宽核函数

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A Characterization of PSL(3. q) for q=2~m

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Acta Mathematica Sinica,English Series 2002年第3期18卷 463-472页

作者： A.IRANMANESH S.H.ALAVI B.KHOSRAVI Department of Mathematics tarbiat modarres University P. O. Bax: 14115-137 Tehran. Iran Institute of Studies in Theoretical Physics and Mathematics Tehran Iran

The order components of a finite group are introduced in [12]. In [9], it is proved that the group PSL(3, q), where q is an odd prime power, is uniquely determined by its order components. In this paper, we show that ... 详细信息

关键词： Finite group Simple group Prime graph Order component

Demographic parameters of cotton aphid, Aphis gossypii Glover （Homoptera： Aphididae） on five cotton cultivars

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Insect Science 2006年第3期13卷 205-210页

作者： JABRAEIL RAZMJOU SAEID MOHARRAMIPOUR YAGHOUB FATHIPOUR SEYED ZIAEDDIN MIRHOSEINI Department of Entomology College of Agriculture Tarbiat Modarres University Tehran Department of SilkwormResearch Faculty of Natural Resources University of Guilan Somehe Sara Iran

Life table parameters of the cotton aphid, Aphis gossypii Glover, were estimated on five cotton cultivars （‘ Sealand＇ ,‘Siokra＇ ,＇ Vararnin＇ ,‘ Bakhtegan＇ and ‘ Sahel＇）. Demographic parameters of the cotton aphid were assessed at 27.5 ± 1 ℃, 65% ＋ 10% RH and a photoperiod of 14：10 （L： D）h. The shortest developmental time for the nymphal stages was 5.5 days on ‘Siokra＇ and the longest was 6.1 days on‘ Sealand＇. The highest offspring per female was 29.6 on ‘Sahel＇ and the lowest was 15.3 on ‘Sealand＇. The rm values varied from 0.272 on ‘Sealand＇ to 0.382 （day^-1） on ‘Varamin＇. Jackknife estimates of the A. gossypii parameters on these cultivars indicated the greatest developmental rate and fecundity on ‘ Varamin＇ and the poorest on ‘ Sealand＇ cultivar.

关键词： Aphis gossypii cotton aphid cultivar demography plant resistance

Effect of Solid Solution Supersaturation on Precipitation of γ′ in Rapidly Quenched Ni-Al Binary Alloys

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Journal of Materials Science & Technology 2009年第1期25卷 130-134页

作者： A. Samadi A. Abdollah-zadeh S. Behrouzghaemi S.H. Razavi Department of Materials Engineering Tarbiat Modarres University P.O. Box 14115-143 Tehran Iran Department of Materials and Metallurgical Engineering Iran University of Science and Technology (IUST) Narmak#16846 Tehran Iran

The effect of solid solution supersaturation on the precipitation of γ＇ in rapidly quenched Ni-AI binary alloys containing 11.6, 14.2 and 16.5 at. pct AI was investigated. The samples were solutioned at 1250℃, quenched in iced brine, and then analyzed by electron microscopy and XRD （X-ray diffraction） techniques. In Ni-11.6 at. pct Al alloy, ordering and phase separation took place simultaneously, resulting in a uniform distribution of γ＇. A transition from uniform to bimodal γ＇ phase distribution occurred in the composition range between 14.2 and 16.5 at. pct Al. This transition was accompanied by changes in the morphology of γ＇ precipitates. The microstructural observations were discussed in view of both kinetics and crystallographic considerations.

关键词： Ni-Al system Heat treatment γ' precipitation Lattice mismatch

Fischer-Tropsch Reaction Kinetics of Cobalt Catalyst in Supercritical Phase

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Journal of Natural Gas Chemistry 2007年第2期16卷 115-120页

作者： Abdullah Irankhah Ali Haghtalab Ebrahim Vasheghani Farahani Kambiz Sadaghianizadeh Department of Chemical Engineering Tarbiat Modarres UniversityP.O.Box 14115-111TehranIran Department of Gas Research Research Institute of Petroleum IndustryP.O.Box 18745-4163TehranIran

Fischer-Tropsch synthesis under supercritical phase condition was examined in a continuous and a high-pressure fixed bed reactor by employing a cobalt catalyst （Co-Ru/γ-Al2O3）. An integral reactor model involving Fischer-Tropsch reaction kinetics in the supercritical fluid n-hexane was used to describe the overall performance. On the basis of Langmuir-Hinshelwood-Hougen-Watson （LHHW） model, the reaction rate constants were obtained for the rate equations of CO conversion to CH4 formation under supercritical conditions.

关键词： Fischer-Tropsch synthesis supercritical phase n-hexane kinetics cobalt

1-Methylimidazole-catalyzed reaction between tosylmethyl isocyanide and dialkyl acetylenedicarboxylates:An efficient synthesis of functionalized pyrroles

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Chinese Chemical Letters 2011年第3期22卷 314-317页

作者： Mehdi Adib Bagher Mohammadi Ehsan Sheikhi Hamid Reza Bijanzadeh School of Chemistry University College of ScienceUniversity of TehranPO Box 14155-6455TehranIran Department of Chemistry Tarbiat Modarres UniversityPO Box 14115-175TehranIran

An efficient 1-methylimidazole-catalyzed synthesis of dialkyl 2-[（4-methylphenyl）sulfonyl]-1H-pyrrole-3,4-dicarboxylates is *** reactive 1：1 zwitterionic intermediate formed by the addition of 1-methylimidazole to dialkyl acetylenedicarboxylates is trapped by tosylmethyl isocyanide（TOSMIC） to afford the title compounds in excellent yields.

关键词： 1-Methylimidazole Tosylmethyl isocyanide Acetylenic esters Pyrrole synthesis