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The soft magnetic nanocrystalline Fe73.5Si13.5B9Cu1Nb3 alloy (FINEMET®) is produced by heat treatment of amorphous precursor. Determining kinetic parameters of amorphous structure transformation to nanocrystalline allows the control of microstructure (e.g. size and volume fraction of nanocrystalline grains) in order to achieve desired soft magnetic properties by optimizing the heat treatment conditions. In this research, the nanocrystallization kinetics of amorphous FINEMET alloy were studied using isoconversional and isokinetic methods under non-isothermal conditions of various heating rates ranging from 5 to 20˚C/min. The changes in the microstructure and magnetic properties of amorphous ribbon during nanocrystallization process were studied using X-ray diffractometry and hysteresisgraph, respectively.

Introduction: Natural capital is essential for human survival and achieving sustainable development goals. Therefore, a scientific framework is required to evaluate regional natural capitals consumption and their capacity to ensure sustainable development. Natural capitals represent the limiting and irreplaceable factors in human well-being and sustainability of every developmental intervention. Degradation of the accumulation and flows of the natural capitals are the fundamental issues in the discussion of environmental sustainability. The current research has been conducted with the aim of investigating the state of ecosystem sustainability by adopting two approaches of ecological footprint and ecosystem services, and in other words, comparing the amount of demand for resources with the supply of goods and services provided by the ecosystem.Materials and Method: In this research, to investigate the sustainability of Nowshahr's natural and urban ecosystem as the case study, first, the trend of land use changes and its associated phenomena in the region have been investigated using ENVI 5.6 software for processing the satellite images. In order to investigate the change process of the study area, Landsat satellite reference images, TM, ETM+ and OLI sensors were used for the time scale of 2002, 2013 and 2020. Then, the classic ecological footprint of the region was calculated for six types of productive ecosystems, including agricultural lands, pastures, fishing areas, forests, built-up lands, and the carbon demand. The areas of these six land cover types were converted into global hectares using yield and equivalence factors. Subsequently, the maximum amount of ecosystem service flow per global hectare was estimated. And after that, the amount of consumption of natural capital accumulation and the occupation of capital flow in the region were investigated. Finally, the ecosystem stability of the study area was investigated using indicators such as the ecological pressure index (EPI), ecological sustainability index (ESI), ratio of capital stock to flows index, flow occupation ratio index, and excessive natural capital flow index.Results: According to the research results in the city of Nowshahr, during the period of 2011-2019, the amount of ecological footprint, ecological deficit and pressure have gradually increased, resulting in a reduction of the ecological balance and stability. Only the pasture, forest and fishing areas are in a stable state meaning that the supply of ecological resources is more than the demand, and the pressure is still within the carrying capacity of the ecosystem. In the period of investigation, the amount of use of stock to natural capital flow has increased and has reached almost four times of natural capital flow.Discussion: Measuring human demand for natural capital and nature's supply is essential for tracking progress, setting goals, and orientating sustainability policies. By combining the two approaches of evaluating ecosystem services and ecological footprint, it is possible to track human demand and nature's supply from a precise subset of ecosystem services, and therefore ecological balance and sustainability can be examined at the local level. Based on the results of the research, the stability of the region and the status of its ecosystem services is threatened by the cultivated land, and mainly the consumption of fossil energy. Based on the results of the research, in the period of investigation, the stability of the city of Nowshahr has decreased and the status of its ecosystem services are threatened by the cultivated land, and mainly the consumption of fossil energy. During this period and considering factors such as land use level, ecological deficit, footprint depth, ecosystem service flow, ecological pressure index, and ecological sustainability index, agricultural land use was the most unsustainable and fishing was the most sustainable use in city of Nowshahr.

One of the most important problems in the management and planning of water resources is to forecast long-term precipitation in arid region and hyper arid regions. In this study, statistical downscaling model (SDSM) is used for study of climate change effects on precipitation. The data used as input to the Model are daily precipitation of Kerman and Bam synoptic stations, NCEP (National Centers for Environmental Prediction) data and the A2 and B2 emission scenarios HadCM3 for the reference period (1971-2001). Using HadCM3 A2, B2 data the precipitation for three period (2010-2039), (2040-2069) and (2070-2099) are predicted and compared with the reference period. We used the first 15 years data (1971-1985) for the calibration and the second 15 years data (1986-2001) for model validation. Research results showed that the precipitation will change and Change directions are positive in some months and negative in other months. After the examination function Indexes results from SDSM model shown that this model has better accuracy and a high ability to predict precipitation in arid region than hyper arid region.

Introduction Table grape is one of the most important horticultural crops in Fars province however in recent years climate change has caused negative effects on phenology and reduced the quantity and quality of its product. Around the world, shade net is used for a different of crops, from fruits and vegetables to nursery plants to protect against strong sunlight, wind, hail and bird injury. Shade net are commonly used in vineyards for early, late harvest, protection from hail, snow, storms, and the prevention of the negative effects of pests and diseases in many countries such as Japan, Thailand, Australia, Chile, the United States and Turkey. This study was conducted to investigate the effect of color type and shading percentage on some characteristics of grapes of Rishbaba cultivar in one of the vineyards of Kavar city in 2019. Materials and Methods The experiment was performed as a factorial experiment based on randomized complete block design with 3 replications with canopy color factors (green, red and white) and shading percentage (30% and 50%) and without canopy (control). Kavar city is located 45 km southeast of the center of the province and has a longitude of 250 and 42 and a latitude of 290 and 11 ". The altitude is 1510 meters above sea level and the average rainfall is 290 mm, the average annual temperature is 22, the maximum temperature is 44 and the minimum temperature is minus 4 degrees Celsius. In this study, some characteristics of vegetative and biochemical traits such as shoot length, number of nodes, internode distance, leaf area and chlorophyll, some environmental indicators (leaf temperature, light intensity and some characteristics of quantitative traits berry and cluster weight and some qualitative traits Similar soluble solids, taste index and vitamin C were examined. Results and Discussion The results showed that green cover with 50% shading had the highest vegetative growth in terms of shoot length (20.87 cm), internode distance (3.80 cm) and leaf area (188.33 cm2) and the lowest shoot length (42 cm) and (48.25 cm2), internode distance (2.97 and 2.58 cm) and leaf area (133.07 and 139.68 cm2) were related to control and white canopy treatments, respectively. Shade net with red color has the highest number of nods (22.77) and with 50% shading the highest amount of total chlorophyll (30.47 mg / g fresh weight), cluster weight (691.67 g) and vitamin C (4.10 mg per 100 ml juice). The white color of the shade caused the highest leaf temperature (29.17 ° C) and light intensity (538.67 watts per square meter). In general, shading reduced the temperature of grape leaves and increasing the percentage of shade had a decreasing effect on light intensity. The shade net also reduces the amount of sunlight reaching the trees and lowers the level of evapotranspiration, which reduces the symptoms of plant water stress and thus increases photosynthesis, plant yield and fruit size. Conclusion Among the different net colors, the highest leaf temperature (29.17 ° C) was related to white color and the lowest (26.92 °C) was related to red and green colors. Among the different colors of the nets, white color had the highest intensity of light (538.67 watts per square meter) and the lowest intensity of light (540.67 watts per square meter) related to green color. The white color of the shade net had an increasing effect on the taste index and the green color had a decreasing effect compared to other colors. Uncoated vines (control) had the highest amount of soluble solids, while green cover with 50% shading had the lowest amount of soluble solids. According to the results of this study, the red canopy had an increasing role in increasing the quantity and quality of bearded grapes, the green canopy caused vegetative growth and the increase in vegetative growth with the percentage of shade had a direct effect. The shade net protected the vines and the crop from sunlight and prevented sunburn. The green canopy with 50% shading had the most positive effect. All treatments had a positive effect on the vegetative growth of vines and among them, green canopy with 50% shading had the greatest effect. All treatments had a positive effect on crop uniformity in terms of size and color and red canopy with 50% shading had the most positive effect on quantity and quality of Rishbaba grapes compared to other treatments.

Energy harvesting is the process of converting different kinds of energy, such as solar, thermal, kinetic energy of fluid, etc., to a usable form of energy. Different kinds of transduction mechanisms are used for energy harvesting. The piezoelectric mechanism has received considerable interest because of its advantages, such as ease of application and working over a wide range of frequencies. Simulation and investigation of energy harvesting from a piezoelectric plate, which is mounted on an elastic beam and located behind a cylinder through flow-induced vibrations, is the subject of the present research. First, the results of the lift and drag coefficients in the fluid flow around a stationary cylinder at Reynolds 200 are compared and validated with the previous studies. After that, by placing an elastic beam and a piezoelectric behind the cylinder, flow around the cylinder, and the fluid-solids interactions are investigated. Due to the vortex shedding phenomenon, which happens in the fluid flow past the cylinder, the elastic piezoelectric beam deforms periodically, and thus, the mechanical energy of the flow is converted into electrical energy. In this problem, the beam effect on both the drag/lift reduction and the amount of voltage extracted from the piezoelectric layer were investigated, and the optimal mode obtained was selected based on the extraction of more energy. In this regard, the process of finding the most optimal energy harvesting mode for the location of the elastic beam, the length of the beam, and the fixed point of the elastic beam in different geometries are carried out. The results of the optimal investigations are as the length of the elastic beam of 2D, the distance of the beam from the back of the cylinder 2.5D, and the state in which the beam is fixed from the right side, where D is the diameter of the cylinder.

Introduction: Minerals are one of the main components of soils which play different roles in the soils. Minerals make up about 50% of the volume of most soils. They provide physical support for plants, and create the water- and air-filled pores that make plant growth possible. Mineral weathering releases plant nutrients which are retained by other minerals through adsorption, cation exchange, and precipitation. Minerals are indicators of the amount of weathering that has taken place, and the presence or absence of particular minerals gives clues to how soils have been formed. The physical and chemical characteristics of soil minerals are important consideration in planning, constructing, and maintaining of buildings, roads, and airports. Clay minerals can be used for understanding of soil formation, optimum management of dry and wet lands and interpretation of paleo environments. Moreover, clay minerals can provide some valuable information such as the origin of sediments, transportation and precipitation of sediments and also some information about intercontinental weathering regimes. Quaternary sediments have occupied most of the agricultural and natural resources of Urima plain and recognition of mineralogical of these soils is essential to optimum and stabile use of these soils. Additionally, caly mineralogical investigation can provide some information about the intensity of weathering processes and climate change in this area. Thus, in this study clay minerals of quaternary sediments in northeast of Urmia and the mechanisms of their formation and also tracing probable climate change in this area were investigated. Materials and Methods: This study was performed in theUrmia plain in west Azerbaijan Province. The study area is located on quaternary sediments and physiographically, this area is a part of a river alluvial plain with the gentle slope toward Urmia Lake. The mean annual precipitation and temperature of this area are 345.37 mm and 10.83 °C respectively and the soil moisture and temperature regimes are dry xeric and mesic respectively. In this study, eight soil profiles in quaternary sediments were dug and sampled and the morphological, physical, chemical and mineralogical properties were determined using standard methods. Results and Discussion: According to the results, Illite, smectite, Kaolinite, chlorite, vermiculite and hydroxy interlayer vermiculite (HIV) were the dominant clay minerals in these soils. The origin of illite, chlorite and kaolinite were related to inheritance from parent material. Regarding to the present of some smectite in the parent material of these soils, some of smectites have been inherited from parent material. Nevertheless it seems that, the most of smectites in these soils have pedogenic origin. Based on mineralogical results and trends variation of smectite and illite along studied profiles, we concluded that some of smectites in these soils have been formed from illite transformation. In profiles 4 and 6, regarding to low depth water table and consequently poor drainage, high pH and high values of calcium and magnesium cations, provide suitable conditions for the neoformation of smectit and so, some of smectites have been formed via neoformation from soil solution. In these soils, vermiculites were pedogenic and have been formed during transformation of illite to smectite. Small amounts of hydroxy interlayer vermiculites were present in buried horizons and regarding that they were not present in parent material, it might be because these minerals are pedogenic and have been formed in a past wetter climate. The transformation of illite to smectite in lower horizons needs high moisture and regarding to recent semiarid climate of study area, the suitable amount of moisture for this transformation, especially in lower depths and also in buried horizons, is not present. Thus, it seems the transformation of illite to smectite in lower depths and buried horizons has been taken place in a wetter past climate. So we concluded that smectite and hydroxy interlayer vermiculite are evidences of a wetter past climate in this area. Conclusion: In this study the origin of smectite in buried horizons was related to transformation of illite. According to high moisture condition which is necessary for the weathering of illite, the occurrence of this process related to more humid climate of the past. Additionally, the presence of hydroxy interlayer vermiculites was related to previously wetter climate as well. So results of this study can be used for recognition of climatic change in the study area.

The main objectives of the present study were to estimate of biomass and maximum sustainable yield of common kilka in Iranian waters of the Caspian Sea. This paper examines the maximum sustainable yield (MSY) and fishing intensity at MSY (fMSY) and then using by fMSY, yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of Fmax, F0.1 and F40%; the acceptable biological catch (ABC) was estimated. The results showed that the catch of three species of kilka were 24080 and 22969 t in 2012-2013 and 2013-2014 in Iranian waters of the Caspian sea, respectively and common kilka predominated with 98.1% and 98.9%, respectively. Growth parameters were estimated as L_∞=141.8 mm, K=0.297 yea^r−1, t_0=−1.048 year^−1. The ages of common kilka comprised 6 age groups, ranged from 1 to 6 years and Age groups 3 and 4 years old had the highest frequency. In the years 2012-2013, the catch of age 1 and age 4 represented the lowest and highest proportion of total catch (133.6 and 9121.6 t). In 2013-2014, followed the catch of age 1 and age 3 had the lowest and highest proportion of total catch (151.9 and 8700.2 t). The instantaneous coefficient of natural mortality was estimated as 0.506 year^−1 and total mortality and the instantaneous coefficient of terminal fishing mortality were 0.894 and 1.40 year^−1 respectively. In the years 2012-2013 and 2013-2014, the biomass of common kilka was estimated 90700 and 83300 t, respectively. Also, the fishing mortality was 0.622 and 0.894 year^−1 and the exploration rates were 0.551 and 0.636. The reference points of common kilka at F0.1 and F40% were estimated 0.92 and 0.80 year^−1, respectively. According to Schafer model the MSY and fMSY were estimated 22670 t and 8690 vessel×nights (a unit of effort). In 2013-2014, the ABC of common kilka was estimated 17500, 20060, 23500 and 18900 t in tiers 2, 3, 4 and 5, respectively. However, for the implementation of a precautionary management approach the lower and more accurate ABC-value, based on more information, should be selected and thus the catch should be restricted to 17500 t.

Anzali wetland at south west of Caspian located along of North West and southeast and with its unique feature were add on the Ramsar convention list in 1975. There were recorded a high rich of fauna and flora including 276 plant species, 23 reptiles and amphibians, 60 fishes, 26 mammals and 195 birds. Anzali wetland were encountered with numerous disorder with the eutrophication and the early dismissing. The first studies on Anzali wetland started by many international institutions in 1964. In this study the data of biotic and abiotic factors in Anzali wetland analyzed which belongs to different sites (15 to 38 stations) during 1991 to 2000 and were sampled seasonally or monthly in different years. The results showed the increasing trend of phytoplankton abundance from 7.9 to 66 million C./l. and the western part had the most abundant. The Cyanophyta had the most development than other 7 phylum observed in the area. In Anzali wetland identified 143 phytoplankton genus that 9 genus dominated in more than 80 % replicates and 7 genus had the abundance of more than 5 million cell/l. The Zooplankton abundant increased from 580 to 2200 ind./l. The Rotatoria had the most abundant followed by Copepoda. There was identified 104 zooplankton genus that 5 genus were dominated in more than 80 % replicates and 11 genus had the abundance of more than 30 ind./L. The chlorophyll a varied from 8.8 to 50.2 μg/l. and had a increasing trend after 1996, meanwhile it was measured higher than 25 μg/l in most of the stations. The results of benthic study showed that the Chironomidae and Tubificidae were observed more than other organisms which comprised 12.2 to 23.5% of total biomass of benthic organisms in studied period. The range of biomass was 1.1 to 7.8 g/m2. The ichthyologic survey showed presence of 60 species that 11 species were exotic. 28 species belong to freshwater, 17 species were anadromous and 8 species were resident in estuary. The highest and lowest fish catch were 640 and 288 ton in 1994 and 1999 respectively and it was about 500 ton at the end of period. The hydrochemical factors had the various fluctuation so that the nutrients parameters had a significant difference over studied period. Total nitrogen was varied from 0.78 to 1.41 mg/l and total phosphorus varied from 0.05 to 0.1 μg/l.. The oxygen dissolved amount was from 4.6 to 8.7. EC was between 3 to 5 ms/cm during September and October that indicated of Caspian water projection. According to geographic position of station, all biotic and abiotic data, were arranged. The data bank is used by Idrisi software to produce of necessary maps. Analysis of data showed that there must be a responsible department with a vast authority. Conservation and eutrophication prevention of Anzali wetland connect to special attention to catchment area and landuse management of the wetland. Also there is an urgent need for well-developed technologies and managements to reduce the organic pollution and its environmental impacts on the Anzali Lagoon. Iranian Fisheries Science Research Institute Published

The subject of this study concerns Urmia Lake which is one of the most valuable water habitats in Iran and investigation of crisis in the drop n of water level, significant decrease in the lake’s surface area and increase in its salinity.. In order to have better understanding of the processes that affect the lake's water level fluctuations and assess the contributions of every responsible parameter, System water consumption was designed. System water consumption was designed in The Lake Basin in the Vensim and the effects of each variable on the water level of the lake were evaluated using a set of different scenarios The findings suggest that in comparison to other variables, the operation of dams (26%) as well as an increase of water requirement (16%) by variables have played a role in reducing the input to the lake. Climate variables had an effect of 16% within the time span of 1999-2014. Although Hydrograph indicates the aquifer deterioration in some of them, the entrance to the lake water budget is negligible

A large portion of the world energy consumption is provided by fossil fuels, which cause massive emissions of dangerous pollutants into the environment leading to global warming and climate change. What is certain is the world's energy consumption in order to increase economic growth and the resulting greenhouse gas emissions, especially carbon dioxide, the consumption of fossil fuels is a growing trend. Therefore in the present study to examine the causal relationship between CO2 emissions (as an alternative to the destruction of the environment variable) and variables of FDI, per capita energy consumption and GDP in the form of an environmental Kuznets hypothesis in Iran during 1980-2008. To that end, The Toda-Yamamoto method, has been used to examine the causality relationship. The main finding of this study shows that there exists bidirectional causality between CO2 emissions and energy consumption and unidirectional causality running from GDP to CO2 emissions. Given the existence of causal relationships between variables, the hypothesis of environmental Kuznets curve (EKC) in state variables that criterion economic growth CO2 emissions and energy consumption is to be confirmed, but in that case the criterion of economic growth, GDP is confirmed is not.