Synthesis and characterization of new heat resistance and organosoluble poly(ether-amide)

New series of olefinic poly(ether-amide)s (OPEA)s 6a-f was synthesized from 4,4′-bis(1,4-diphenoxybutane)diacrylic acid 4 and aromatic diamine 5a-f via a direct polycondensation reaction. The resulting polymers were characterized by Fourier transform infrared spectra (FTIR), nuclear magnetic resonance (1H-NMR), solubility test and inherent viscosity. The thermal properties of the polymers 6a-c were investigated by thermogravimetric analysis (TGA). Polymer 6c due to presence of SO2 group as a polar group shows better thermal properties compare with polymer 6a and 6b. KEY WORDS: Polycondensation, Polyamide, Ether group, Thermal properties Bull. Chem. Soc. Ethiop. 2013, 27(3), 413-419.DOI: http://dx.doi.org/10.4314/bcse.v27i3.1

Microdust impact on leaf gas exchange parameters in oak species of Northern Zagros forests, west of Iran

In recent years, the microdust phenomenon has greatly changed in concentration, duration and continuity as well as the frequency of occurrence in comparison with dust storms in the past which has caused a great deal of concern. Microdust is one of the most devastating factors in the environment threatening all animal and plant species. Regarding to the microdust impending threat, its ecological and economic impacts on scarce species is critical. Zagros forests act as an intrinsic filter for microdust in the western region of Iran. This study investigates the effect of microdust on oak, the most important tree in the Zagros forests. So that, three-year old seedlings of three oak species (Quercus branti, Q. libni and Q. infectoria) were exposed to microdust under natural conditions during spring and summer 2016. We examined the rate of photosynthesis, stomatal conductance, transpiration, internal CO2, mesophyll conductance, water use efficiency in control and treated plants. The results indicated that microdust had a significant impact on the examined parameters of the three oak species (P≤0.01). The gas exchange and photosynthetic rates of the treated plants were significantly reduced. In Q. infectoria, microdust had the greatest impact on photosynthesis, stomatal conductance, leaf internal CO2, transpiration and mesophyll conductance. Accordingly, microdust had a substantial influence on photosynthesis and mesophyll conductance in Q. brantii as well as the leaf internal CO2 and mesophyll conductance in Q. libani. Therefore, based on these findings, it can be concluded that microdust can disrupt the physiological activities of the examined species. Hence, continuous - exposure to microdust will accelerate the process of destruction of these forests

Risk zone mapping of forest fire using GIS and AHP in a part of Paveh forests

Forest fires, as an ecological risk, whether with human or natural origin, have profound effects on land cover, land use, production, local economies, global trace gas emissions, and health. Identification of factors affecting the existence of forest fire as well as its zonation in the given watershed is one of the basic tools for forest fire control and fighting actions. The aim of this research is to develop the forest fire risk map based on vegetation, physiographic and climatic factors, human, distance to rivers and roads, in a part of Paveh forests. For this purpose, digitally diffusion forest fires map with field checks using GPS were prepared, initially. Then affecting factors were binary compared using Analytical Hierarchy Process (AHP) method by indicating the weight of each factor as indicator for their effects in occurrence of forest fire. Accordingly, the forest fire zonation risk map was prepared using weighted information layers and weighted coefficient of each factor. Five categories of forest fire risk, including very high to very low, were derived, automatically. The mapping result of the study area was found to be in strong agreement with actual fire-affected sites. The results indicate that the 90% of burned areas are located in high risk class

The effects of business cycle indicators on stock market indices of food industry in Iran

This paper investigates the effects of the business cycle indicators on stock market indices of food industry companies in Iran stock market. Using dynamic panel and Panel VAR methods for seasonal data of 2001-2015, the results show that the effect of GDP and agricultural value-added as indicators of business cycle on stock market indices of sales volume, price index, net profit and stock return are positive. The results of panel VAR models also show that the shocks entered by GDP and agricultural value ?added have a different effect on stock market indices of sales volume, price index, net profit and ?stock return. Due to the positive effects of the business cycles indicators on the stock market indices of food industry companies, it is recommended that policy-makers consider strategies to increase GDP and agriculture value-added. Acknowledgement : I am attaching herewith a manuscript entitled ?The Impacts of Business Cycle Indicators on Stock Market Indices of Food Industry for the 30th international conference of agricultural economics. With the submission of this manuscript, I would like to undertake that the above-mentioned manuscript has not been published elsewhere, accepted for publication elsewhere or under editorial review for publication elsewhere. Please don't hesitate to contact me for further information. Thanks in advance for your time and consideration. Sincerely Hosein Mohammadi, Associate Professor of Agricultural Economics Ferdowsi University of Mashhad, Ira

Soil recovery assessment after timber harvesting based on the sustainable forest operation (SFO) perspective in iranian temperate forests

Minimizing the impact of timber harvesting on forest stands and soils is one of the main goals of sustainable forest operation (SFO). Thus, it is necessary to make an accurate assessment of forest operations on soil that is based on the SFO perspective. The present study was conducted according to SFO principles to investigate the time required for the natural recovery of soil after disturbance by skidding operations in some Iranian forests. The physical, chemical, and biological properties of soil found in abandoned skid trails from different time periods were compared with undisturbed forest soils. The soil bulk density, the penetration resistance, and the microporosity of a 25-year-old skid trail were 8.4-27.4% and 50.4% greater, and the total porosity, macroporosity, and soil moisture were 1.9-17.1% and 4.6% lower than the undisturbed area. In a 25-year-old skid trail, the values of pH, Electrical conductivity (EC), C, N, available P, K, Ca, and Mg, earthworm density, and biomass were lower than in the undisturbed area, and the C/N ratio value was higher than in the undisturbed area. High traffic intensity and slope classes of 20-30% in a three-year-old skid trail had the greatest impact on soil properties. In order to have sustainable timber production, SFO should be developed and soil recovery time should be reduced through post-harvest management operation