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New optically active and thermally stable poly(amide-imide)s containing N,N'-(Bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic)-bis-L-alanine and aromatic diamines: synthesis and characterization
Faghihi, Khalil;Absalar, Morteza;Hajibeygi, Mohsen;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009001000024
Abstract: five new optically active poly(amide-imide)s (pais) 6a-e were prepared by direct polycondensation reaction of the newly synthesized n,n′-(bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetra carboxylic)-bis-l-alanine 4 with various aromatic diamines 5a-e using polar aprotic solvents such as n-methyl-2-pyrrolidone (nmp). in this technique triphenyl phosphite (tpp) and pyridine were used as condensing agents to form poly(amide-imide)s through the n-phosphonium salts of pyridine. all of the polymers were obtained in quantitative yields with inherent viscosities between 0.29-0.46 dl g-1 and were highly soluble in polar aprotic solvents such as n,n-dimethyl acetamide (dmac), n,n-dimethyl formamide (dmf), dimethyl sulfoxide (dmso), n-methyl-2-pyrrolidone (nmp) and solvents such as sulfuric acid. they were fully characterized by means of 1h nmr, ftir spectroscopy, elemental analyses, inherent viscosity, solubility test, specific rotation and thermal properties of these polymers were investigated using thermogravimetric analysis techniques (tga and dtg).
Thermodynamic Analysis of ZnO Crystal Growth from the Melt  [PDF]
Morteza Asadian
Journal of Crystallization Process and Technology (JCPT) , 2013, DOI: 10.4236/jcpt.2013.33012
Abstract: Recently, the efforts in solid-state materials include developing technologies capable of producing ZnO wafers in large dimensions and good quality based device applications. High quality bulk crystals are obtained by growing from high purity the melt. However, the thermochemical properties of ZnO (high melting point and high vapor pressure) make the growth of single crystals difficult. The thermodynamic calculations show that ZnO crystals can be grown from the melt if a suitable dynamic atmosphere composition is used. The oxygen requirement with increasing the temperature can be fulfilled by adding the NO-NO2 gases into the CO2 atmosphere. At ZnO melting point, the oxygen partial pressure of gas mixtures containing CO2-NO-CO-NO2 at Pt = 5 atm reaches to PO2 = 0.29 atm. According to this new thermodynamic result, it would be expected that ZnO crystal could be grown from the melt at lower total pressure comparing to pure CO2.
Application of the Two Nonzero Component Lemma in Resource Allocation  [PDF]
Morteza Seddighin
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.27072

In this paper we will generalize the author's two nonzero component lemma to general self-reducing functions and utilize it to find closed from answers for some resource allocation problems.

Proving and Extending Greub-Reinboldt Inequality Using the Two Nonzero Component Lemma  [PDF]
Morteza Seddighin
Advances in Linear Algebra & Matrix Theory (ALAMT) , 2014, DOI: 10.4236/alamt.2014.42010
We will use the author’s Two Nonzero Component Lemma to give a new proof for the Greub-Reinboldt Inequality. This method has the advantage of showing exactly when the inequality becomes equality. It also provides information about vectors for which the inequality becomes equality. Furthermore, using the Two Nonzero Component Lemma, we will generalize Greub-Reinboldt Inequality to operators on infinite dimensional separable Hilbert spaces.
Investigating the Impact of Climate Changes on Qualitative and Quantitative Growth of Oak Trees (Case Study: Central Zagros)  [PDF]
Morteza Habibi
Open Journal of Ecology (OJE) , 2016, DOI: 10.4236/oje.2016.66034
Abstract: The present study is an attempt to investigate the impact of climate changes on quantitative and qualitative growth of oak trees in central Zagros region. After we selected the study region, 35 discs were taken from trees felled in each height class (e.g. 1400 - 1600, 1600 - 1800, 1800 - 2000 m above the sea level). We used climate index spi. For the data analysis, we employed SPSS software and inferential statistics tests of Kolmogroff Smirnov and the one-way ANOVA. During the recent 15 years, rainfall has shown a decreasing trend and amount of haze and frequency of occurring haze has been increased. The ANOVA results indicated that diameter growth of trees in three height classes revealed a significant difference. The average annual diameter growth in the first, second and third classes were 1.8 mm, 2.5 mm, and 2.2 mm, respectively. Additionally, the results indicated that hillsides and slope aspect has a statistically meaningful effect on the size of canopy area, basal area and number per hectare. Several different studies have reported that during the recent 15 years, qualitative and quantitative growth of central Zagros oak trees strongly correlate with climate parameters in the three habitats.
Analyzing Direct and Indirect Effects of Economic Sanctions on I. R. Iran Economic Growth: Focusing on the External Sector of the Economy  [PDF]
Morteza Ezzati
Open Journal of Marine Science (OJMS) , 2016, DOI: 10.4236/ojms.2016.64038
Abstract: In this paper, we analyze direct and indirect effects of economic sanctions on I. R. Iran’s economic growth from 1979 to 2012 focusing on the external sector of the economy. Our data for variables except for sanction are derived from 1966 to 2012 and a dummy variable is used for each sanction’s beginning years. The designed model is based on the endogenous growth models in which we analyze the effects by 2SLS econometric method. Our findings indicate that economic sanctions have not directly affected Iran’s economic growth so much. These effects have been indirect through restricting total imports, capital goods imports, imports of intermediate goods and primary products and also the export leading to decreased economic growth of the country.
Two Nonzero Component Lemma and Matrix Trigonometry  [PDF]
Morteza Seddighin
Advances in Linear Algebra & Matrix Theory (ALAMT) , 2017, DOI: 10.4236/alamt.2017.71001
Abstract: In this paper we show that the author’s Two Nonzero Lemma (TNCL) can be applied to present a simple proof for a very useful equality which was first proved by Karl Gustafson in 1968. Gustafson used Hilbert space methods, including convexity of the Hilbert space norm, to prove this identity which was the basis of his matrix trigonometry. By applying TNCL, we will reduce the problem to a simple problem of ordinary calculus.
Extending Kantorovich-Type Inequalities to Normal Operators  [PDF]
Morteza Seddighin
Advances in Linear Algebra & Matrix Theory (ALAMT) , 2018, DOI: 10.4236/alamt.2018.81005
Abstract: We will extend some of the Kantorovich-Type inequalities for positive finite dimensional matrices to infinite dimensional normal operators by applying The Two-Nonzero Component Lemma and converting them to an An-tieigenvalue-Type problem.
Cotton and Soil Responses to Annual Potassium Fertilization Rate  [PDF]
Morteza Mozaffari
Agricultural Sciences (AS) , 2018, DOI: 10.4236/as.2018.96054
Abstract: The objective of this study was to evaluate the effect of potassium (K) fertilization rate (0, 27.9, 56.4, 84.7, 112.9, and 141.1 kg K/ha) and cotton (Gossypium hirsutumn L.) cultivars of slightly differing maturity on seedcotton yield and Mehlich-3 soil-test K concentrations. The cotton cultivars “Stoneville 4892” and “Stoneville 5599” represented long-season cultivars while “Paymaster 1218” and “Deltapine 444” represented early-season cultivars. The same K fertilizer treatments were applied to the same plots during the three years of the study. Higher order interactions of cropping year, cotton cultivar and K-fertilization rates were not significant (P ≥ 0.50), indicating the two cultivars of slightly different maturity respond similarly to K-fertilization. Cropping year and K-fertilizer application rates significantly affected seedcotton yield (P < 0.0001). Potassium fertilization did not significantly influence seedcotton yield in the first year but significantly increased seedcotton yield in second and third year (P ≤ 0.0074), as well as 3-year average, and total seedcotton yields (P ≤ 0.0006). Seedcotton yields ranged from 3418 to 4127 kg·ha-1 and 2980 to 3487 kg·ha-1 in the second and third year respectively while 3-year average and total seedcotton yields were 2943 to 3443 and 8832 to 10,330 kg·ha-1. The relation between annual, 3-year average, and total K application rates and seedcotton yield was linear (R2 ≥ 0.82, P ≤ 0.0125). Potassium fertilization significantly increased post-harvest (fall) Mehlich-3 extractable soil K in all three years (P ≤ 0.0002). This study indicated that, in a representative Mississippi River Delta silt loam soil, when Mehlich-3 extractable K was <98 mg·kg-1, K fertilization was needed to increase seedcotton yield and prevent soil K depletion. This supports the current University of Arkansas fertilizer recommendations for irrigated cotton production, where application of 56 kg of K ha-1 is recommended to optimize seedcotton yield and prevent soil K reserve depletion when Mehlich-3 extractable soil test K is medium (91 - 130 mg/kg).
Synthesis and characterization of thermally stable poly(amide-imide)-montmorillonite nanocomposites based on bis(4-carboxyphenyl)-N,N'-pyromellitimide acid
K. Faghihi, A. Asghari, M. Hajibeygi
Bulletin of the Chemical Society of Ethiopia , 2013,
Abstract: Two new poly(amide-imide)-montmorillonite reinforced nanocomposites containing bis(4-carboxyphenyl)-N,N'-pyromellitimide acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) as a source of polymer matrix was synthesized by the direct polycondensation reaction of bis(4-carboxyphenyl)-N,N'-pyromellitimide acid with 4,4'-diamino diphenyl sulfone in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films with 10 and 20% silicate particles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-Vis spectroscopy, thermal gravimetry analysis (TGA) and water uptake measurements. KEYWORDS: Bis(4-carboxyphenyl)-N,N'-pyromellitimide acid moiety, Poly(amide-imide)-montmorillonite nanocomposite, Thermal properties Bull. Chem. Soc. Ethiop. 2013, 27(1), 95-104. DOI: http://dx.doi.org/10.4314/bcse.v27i1.10
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