دکتر نادر پروین

The Safavid dynasty (1135-907) was the result of more than two centuries of patient preparation of Safavid sheikhs to reach power. Until before the period of Ṣāfī al-Din Ardabili, the Sufis turned to isolation and distance from the centers of political power. during the period of the Safavid sheikhs, a kind of metamorphosis occurred in the thought of the Safavid sheikhs, which can be referred to as their gradual entry into politics using financial and social Struggles. The present research tries to answer this basic question by using the descriptive-analytical approach and the library method, what were the most important financial and social efforts of the Safavid sheikhs in the long time and stable management of the Safavid Tariqa? The research hypothesizes that the Safavid sheikhs managed the Tariqa and established the government in a long process by relying on people and informal financial and social efforts. The results of the research show that the Safavid sheikhs, through creating links between rural and nomadic areas with the city institution and using the financial capacities of these three institutions, Optimized of incomes related to endowment  (waqf), khums (xums(, zakat and Anfal, people-oriented management of the Safavid Tariqa, Emphasis on clean bite, financial benefit from holy war with Shirvanshahs infidels, attention to the oppressed and poor layers and utilization of bureau and tax exemptions that granted by the concurrent rulers, in a long time and patient process, succeeded to establish the Safavid government.

Understanding the Attributes and Interactions of Forms and Processes Governing River Systems that Understand the Behavior of Rivers in Temporal and Spatial Bounds The importance of developing conceptual models for the environment is of particular importance. There are rivers. In this study, the stability of the Gadar River waterway based on the Nanson and Knight models is evaluated to evaluate the dynamic behavior of the Gadar river and its effect on the river bed changes based on the Nanson and Knighton designs. The aim of this study. The research method is a descriptive-analytical one. Required parameters were extracted from hydrometer station statistics, fieldwork, topographic maps, land use maps, Google Earth application and Auto Cad, WMS9.1, Smada and ARC GIS software. This model divides the Anabench rivers into six classes based on flow power parameters, bed load size, particle size, lateral displacement, islet length to channel ratio. In the range of type five and index of the degree of coherence and vertical increase of islands and sinusoidal ducts are in the range of type one. The islands have grown more rapidly in the arterial and direct intervals because of the greater widths than in the other, and in the Meander interval between the Kiel-Sheen heights to the low-lying village. In the third period, the sediment type of the riverbed and the valley where the river flows is erodible and the width of the riverbed is high, but in the first period, the sediment and bedrock are of the erosion resistant formations. Either there were fewer river changes or very little change. The Gadar River is similar to any of the six tributary tributary rivers and, in general, this channel is not fully coherent with the Nanson and Neyton designs.

Rivers are one of the best geomorphic landscapes of the earth, where the link between the system of forces and the forms of roughness can be clearly understood. Studying the morphological pattern of rivers is essential for understanding current conditions and their potential for future changes, and only then can their natural responses to natural changes or actions resulting from the implementation of remediation schemes be possible. It predicted the direction and fixation of the edges and recognized the extent of their displacement and variations in their dimensions and patterns. In the northwestern part of the country, developed river systems play an essential role in the geomorphological developments of the region. The study area is located in the city of Ashnoye in northwest of the country. The purpose of this study was to investigate and evaluate the dynamic behavior of the Gadder River and its effect on river bed changes based on Nanson and Newton designs.

Data and Methods:

The research process involved collecting data, field studies, generating information layers and adapting them to the status quo, analyzing each layer to investigate the role of the Gadder River morphodynamics in canal stability and evaluation based on the model. Nanson and Nathan. To evaluate the Gadder River based on this model parameters such as flow power, bed load size and size, particle size of the boundaries, lateral displacement ratio, islet length to channel width, coherence rate and vertical islet and channel sinusitis Used. Finally, the role of each of the variables was identified as influencing factors in the stability of the Gadder River.

In areas where the conduit turns into an anchor, the slope of the upstream stream is minimized and changes noticeably. At the end, when the slope decreases sharply, the river changes into an arterial one. More than 95 percent of the coarse-grained sediments are due to the high river discharge to carry the coarse-grained sediments and to the greater adhesion of the riverbanks that are prone to coarse-grained sediments.
The erosion of the river bed (Push Abad village to Darband village) was also observed in the sections where the sediment type was erodible (third interval). In areas where the sediment type is bedrock-resistant, there have been fewer or very minor river changes, such as the first section. The arterial and direct intervals have increased more than other intervals due to the greater width and in the meandering interval between the Kilehin heights to the village of Hazrat Zaza. The fluctuations and changes in the sinocyte coefficient of the river Gadar were lower in the first interval due to the first mountainous interval due to the river route. In the second and third intervals, the rate of sinocytic coefficient increased in the year 1396 compared to the year 1395, indicating a complex increase in the rivers in these two intervals, resulting in a change in river morphology in these intervals. The comparative results based on the evaluation and the parameters of the Gadder River in different types of design indicate that the Gadder River has similarities with each of the six types of Anabench rivers and, in general, this channel coincides with the Nanson and Knighton designs. Do not match perfectly.

The Gadar River islands have grown more in arterial and direct intervals due to their greater width than in other meandering intervals, between the Kileen Heights to the lowland village. In the third period, the sediments of the riverbed and the valley where the river flows are erodible and the width of the riverbed has been displaced for most of the length of this section about 10 to 15 meters. However, during the first period, the sediment type of the riverbed is a type of erosion resistant formations. In the specific and local formation of this anterarchic arterial pattern, neotectonics played the most important role as a locus-setting regulator. The locally developed set of these factors has been a factor in the complete non-conformity of the Gadder River with the Nanson and Newton designs.

The attack of the Seljuk Turks affected Iranian society and economy and caused an economic downturn of the society for some decades. Nizam al-Mulk Tusi (408-485 AH) was one of the Iranian bureaucrats during the Seljuk period who had valuable experiences of the economic and peasant traditions of Iran and by writing Siyar al-mulûk took an active approach and action in both the theoretical and practical fields about issues and challenges of his era. The main question of the research is what were the most important economic approaches of Nizam al-Mulk in the Seljuk court and military structure based on Siyar al-mulûk? The result of the research indicates that the most important theoretical and practical approaches of Nizam al-Mulk in the economic structure of the Seljuk government were monitoring the country's expenditure and the financial performance of the officials, the bureaucrats, and the judges, the necessity to pay attention to the rights and livelihood of the peasants and masses, preventing the bribery of doorkeepers and judges, improving the livelihood and the necessity to increase the military budget, the necessity of imposing taxes on conquered lands, supporting state and governmental ownership in a broad way and private ownership in a limited and conditional way.

In Shahnameh, Ferdowsi narrates the cultural components of the identity of ancient Iran in the light of political approaches. The present article tries to answer the question of how Ferdowsi and with what components, aspects and cultural elements, using descriptive-analytical method and theoretical foundations based on political culture, which includes intermediate and related structures of culture and politics. Does it link ancient Iran to politics?
Findings show that in Shahnameh, although the two aspects of culture and politics are expanded and taken, but they are so intertwined and related that it is almost impossible to separate them from each other, for example, culture of tolerance is integrated with the political concept of the Shah of Iran Sharia is placed next to the monarchy.The essence and art of a true political system becomes possible.. Justice, which was intended to establish order and prevent chaos, is administered by the king himself. Shahriari has a divine basis and the demise of Farah Izadi is accompanied by the domination of others, demons and magic. Geographically, one of the aspects of the identity of ancient Iran in Ferdowsi Shahnameh is the geographical borders of Iran, which is a geographical idea of Iranians in accordance with political and national traditions, which is completely related to the myths of creation

The effect of wind cooling in combination with temperature, which is expressed as a special feeling, is called Wind Chill, and the Wind Chill index is used to show the effects of cold. Wind Chills Apart from their beneficial effects on agriculture, they, as one of the natural disasters of atmospheric damage, sometimes cause a lot of financial and even human losses. Since temperature, precipitation and wind are the main elements of climate formation in any region, changes in their behavior can change the climate structure of any region. Therefore, the study of the past trends and behaviors of these climatic elements in the form of various indicators and scales of time and space, is very important and has been a large part of climate research. Researchers' past research shows that temperatures and changes are noticeable in many parts of the world. A review of these valuable sources shows that, so far, many efforts have been made with different approaches and perspectives on the quantitative and qualitative status of temperature and wind speed and related indicators. But what is certain is that no scientific and comprehensive study has been done in Kurdistan province regarding Wind Chills in Zarrineh Obato high plain. Therefore, conducting this study is a special necessity and can be a small step and a starting point to study and explain the specific environmental phenomena of this geographical area in the cold period of the year. One of the questions that arises is whether the behavior of Wind Chills in the Zarrineh Obato Plain has changed over the last three decades.

The main purpose of this study is to study climatic elements and changes in atmospheric phenomena, especially wind chills indexing and their classification in order to study and model the past behavior of Wind Chills during the last three decades using Mann-Kendall graphical statistical method and polynomial regression. To help decision-makers manage and reduce the effects of wind chills.Research MethodsIn order to investigate the past behavior of Wind Chills in Zarrineh Obato plain, after collecting and summarizing daily data on temperature and wind speed of stations around the plain during the statistical period of 32 years (1989-2020), the status of data in terms of quantity and quality control The normality and homogeneity of the data were assessed using the Run Test. Then, according to the latest model of the Canadian Meteorological Organization, the Wind Chill index was defined by establishing temperature conditions of at least 2 degrees Celsius and wind speeds above 4.8 meters per second on a five-point Likert scale. After that, the frequency and intensity of wind chills were calculated and used as the basis for descriptive statistics analysis in SPSS and Excel software. Then, to identify the linear and nonlinear behavior and fit the trend line and calculate its slope, polynomial nonlinear polynomial regression was used based on the least squares size method. In addition, Man-Kendall test and T statistic of Man-Kendall were used to investigate the possible deviation and to determine the type and time of change in the time series of mean temperature, wind speed and wind chill index for the station closest to Zarrineh plain.

The results showed that in February, Wind Chills first (zero to -9 C˚) and second (-10 to -27 C˚) had the highest frequency of occurrence, and although based on the fit of the linear regression equation, The frequency of Wind Chills has been increasing overall, but unlike the second floor Wind Chills, this upward trend has been more related to the frequency of first floor Wind Chills and the significant increase in their number. The frequency of days with Wind Chill on the first floor was about 64% of the total Wind Chills and the frequency of Wind Chills on the second floor was about 36%. In the middle of the study period, there was a clear discrepancy and inconsistency between the frequencies of Wind Chills of the mentioned classes. This means that, in the years when the incidence of Wind Chills increased, the frequency of Wind Chills decreased relatively severely, both in number and severity. Although due to the mountainous nature of Kurdistan region and statistical limitations and lack of automated meteorological stations in the region, it is not easy and reliable to talk about climate and its changes, but the results of Mann-Kendall model analysis on the frequency of wind chills and The average annual temperature intensity of Wind Chills in the plain showed that, so far, there have been several jumps and the beginning of sudden changes in the frequency of Wind Chills during the 1990's. However, since the intersections of the two components U and U' related to the Man-Kendall statistical-graphic diagram within each other within the critical ±1.96 range intersected, so no significant jump was proven, but there are clear signs and signs of a decreasing trend. Wind chills are common in the time series, especially in the two decades of 2010-2020. The changes of the mentioned components for the annual average temperature of Wind Chills of different classes with the frequency of their occurrence have been completely different and vice versa. Thus, although the average temperature of Wind Chills has decreased in the two decades of 2000-2010, but as can be seen from the U' component diagram, the increasing annual average temperature of Wind Chills for the first and second temperature classes and the average temperature of total Wind Chills during the 2010's Shows an upward trend. This means that the average temperature of Wind Chills in the Zarrineh Obatovo Plain has increased significantly since the early 2020's. This issue was also emphasized by the field study and the statements of the villagers in the study area. The result of this research, with a slight difference in the study area, is consistent with the valuable work of many researchers on the beginning of the increasing trend of temperature in different regions of Iran during the last two decades.In general, the winter temperature in the region has increased, and as a result, both the coldness of Wind Chills and the frequency of their occurrence have changed. Thus, the cooling temperature of Wind Chills has been decreasing and in 1990 it has experienced a significant jump. Since the mid-1990's, the annual frequency of the first floor of Wind Chills has been declining, showing several significant jumps, and has lost its long-term normal state.

Due to the kind of its usage in a relatively long period, the analysis of temperature levels of modern cities is among the most important subjects that can be considered in the field of geography and environment, and its results can be used in promoting the science and solving the problems of today’s societies. The effect of temperature on climate, especially in metropolises, is one of the crucial indexes of this procedure. The rise in the land surface temperature, which is an indicator of the heat intensity, is among the important elements for identifying the changes in weather. The emergence of heat in cities is one of the most known forms of such changes. Urban heat islands are indicated by a temperature inversion and annoying temperatures throughout winters and summers. The temperature of some cities or urban areas has remarkably grown compared to the suburbs or rural areas around them. This phenomenon, called urban heat island, has caused numerous problems. The term “heat island” was proposed by Havard for the first time almost a century ago in 1833 (Sook, 2004: 10). Afterward, numerous studies were carried out in the large and industrialized cities of the world, whose results demonstrated that civilization has exerted significant changes in the meteorological parameters and properties of the ground surface, and consequently, remarkable variations in local climate (Mousavi Baygi et al., 2012: 36).

The present research is aimed at identifying the places with high heat, which have created the known thermal patterns in the city of Arak in Iran. Assessment of the spatial-temporal variations of the urban heat islands can be used as a critical component in the management strategies of natural resources and environmental changes, whose results can be useful for environmental, regional, and urban planners.

The studied area, Arak, is the capital of the Markazi Province in Iran, with an area of 304.8 km2 at 1755 m above mean sea level. The city has temperate weather tending to cold and semi-arid. According to enactment in 2011, Arak has five municipal districts.
The research method was analytical-statistical, and an effort was made to evaluate the relationship between land surface temperature and land cover of the city. In order to evaluate the development of hot places in Arak and determine its urban thermal patterns and heat islands in the long term, the data of the satellite images of the Landsat scanners 4, 5, 7, and 8, including the data of the TM scanners of Landsat’s 4 and 5, Landsat 7 (+ETM), and Landsat 8 (OLI/TIRS), during the period 1985-2017 were used. These images include two sets of reflective spectral and thermal bands. The thermal bands were used to identify the surface temperature and thermal islands, and the reflective bands were employed to apply the indexes of image processing. The data of the TM, +ETM, and OLI/TIRS scanners were provided in the bands 6, 8, and 11, respectively. The data of the thermal band 6 of Landsats 5 and 7 with wavelengths of 10.40-12.5 micrometers and the band 10 of Landsat 8 with wavelengths of 10.60-11.19 micrometers were used to calculate the surface temperature distribution patterns of Arak. The bands 3 and 4 of Landsats 5 and 7, along with bands 4 and 5 of Landsat 8, were also utilized to calculate the NDVI index (NASA, 2014). In the global imaging system, the images of the area of Arak exist in the 165th And 36th row.
Generally, the following steps were taken to analyze the urban heat islands of Arak:
Calculation of LST and spectral radiance
Conversion of the calculated radiation to Kelvin temperature
Calculation of the temperature levels of five districts of Arak
Calculation of the density percentage of the fourth level of temperature (hot points of the city)
The minimum, maximum, and average temperatures of Arak
Calculation of normalized difference vegetation index (NDVI)
Calculation of the urban thermal field variance index (UTFVI)

Evaluation of the land surface temperature changes and patterns
The analysis of the vegetation variations demonstrated that depending on different uses of urban lands, vegetation is in accordance with the temperature level. Generally, the low temperature in the southwest of the city, which was observed in the land surface temperature maps, is caused by the gardens of the cities of Senejan and Karahroud. The eastern and southeastern parts of district 1, which has industrial uses, streets with heavy traffic, and accumulation of uses, and the north of the city, i.e., the north of district 3 with the accumulation of residential uses and heavy traffics, have higher temperatures. Generally, during the studied period on vegetation, all areas having this use, except for the northwestern part, had considerable changes. Most of the vegetation in the studied period was concentrated in districts 4 and 5, which included the gardens of Senejan and Karahroud. However, other parts of the city, including the northwest and, to some extent, the city center and district 1, whose vegetation includes several parks and green spaces, show decreasing changes in temperature. Based on the results obtained from evaluating the urban thermal field variance index (UTFV) of Arak, using 20 land surface temperature (LST) maps and normalized difference vegetation index (NDVI), obtained from Landsat satellite, (TM), (ETM+), (OLI/TRS), the very hot temperature level of Arak was widely observed mostly in the north, northeast, east, and southeast of district 1, north and northwest of district 3, west and southwest of district 2, and district 5.

The evaluation of the LST maps to identify the hot points and urban thermal patterns revealed that most of the hot points are located in the areas with idle lands in the suburbs. These lands are mostly observed in the recently developed areas of the suburbs, including districts 1 and 3. Inside the city, most of the hot places conform to the formation of thermal patterns close to industrial towns, streets with heavy traffic and high pollution, and residential areas with dense and urban decay. The largest area of the third temperature level is observed in district 1 due to the presence of industrial towns, dense residential towns, cultural and governmental organizations, heavy traffics in the streets, the northern and southern belts in the district, and idle lands in the north and east of the district. The presence of the industrial towns and factories in the city of Arak, especially in district 1, is one of the effective factors in increasing the heat and creating thermal patterns. The thermal patterns in district 1 had the highest intensity in 1988/09/08 and 2017/01/08 during the studied period.

One of the most important historians of the Ilkhanate period who played an important role in restoring Iranian identity and consciousness is Hamdollah In the present study, which is based on a combined and synthetic method, ie a combination of explanatory method (causation) and interpretive interpretive method (meaningful), an attempt has been made to identify the most important components of Hamdollah Mostofi Qazvini who have helped revive Iranian consciousness and identity. , To be examined. Findings show that Hamdollah Mostofi’s repeated and deliberate attention to the name of Iran and the use of titles and combinations such as “Iran Zamin”, “Mamluk Iran”, “Behesht Abad” and “Kingdom of Iran Putting the name of Iran and Iran in front of its natural enemies, including Turanians, Arabs, emphasizing the geography of Iran from Jeyhun and the borders of Khudzhand to the Euphrates, even from China to the Mediterranean, enumerating and showing the good deeds of Iranians and emphasizing the cultural and spiritual honors of ancient Iran And the Islamic period The most important components considered by Hamdollah Mostofi in her works, which along with other cultural factors have led to the restoration of Iranian consciousness and identity in that period.

Among various manufacturing processes, the use of cold press- sintering has been considered with low cost, high efficiency, and the ability to produce components with the appropriate dimensional accuracy. In this method, at least two components of the alcoholic solution are used in granulation and milling steps. Removing the solutions is accompanied with energy consumption, as well as, an increment in probability of crack initiation, which may limited the widespread utilization of press-sintering process. Therefore, in the present study, the soluble component in the milling step was removed. In following just using PVA as a soluble component in the granulation step, the ceramic / ceramic composite was made. Doing this, samples based on NiO and YSZ were made with different weight percentages of the reinforcement component (25, 30 and 35% wt. zirconia-stabilized yttrium), and then their microstructure, density and micro-hardness were investigated. Microstructural studies indicate that the amount and distribution of porosity, surface quality and depth of cracks in the samples are depended on reinforcement weight. In detailed, at the surface of green tables, no deep crack was observed. In sintered specimens, the best distribution of the gas phase was observed in NiO- 30% wt. YSZ, which results in maximum micro-hardness. Also, the radiography results provided by the above samples indicated that deep crack in the discs is not visible. Therefore, it seems that the starch as a pore former displayed the beset role via porosity distribution and lessening crack nucleation in sample having 30% reinforcement.

In the present research, wear behavior of Cr2O3-20YSZ (CZ) and Cr2O3 (C) coatings created using atmospheric plasma spray (APS) process was evaluated. For this purpose, Cr2O3 and YSZ nanopowders were produced after milling for 5h in a high-energy ball mill and subsequently plasma spraying of the agglomerated powders was carried out on 304L substrates. Microstructural characterization of these ceramic coatings was performed using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and optical microscope. Mechanical tests including adhesive strength, fracture toughness, and micro-hardness were used so as to explain the coatings wear behavior. Sliding wear test was conducted using a ball-on-disk configuration against an alumina counterpart at room temperature. Addition of YSZ particles to the Cr2O3 matrix due to the phase transformation toughening mechanism associated with tetragonal zirconia resulted in an increase in the fracture toughness while decreased the micro-hardness. It was found that the composite coatings had the friction coefficients of the proper order of 0.11-0.15. The CZ composite coating compared to the C coating showed the higher wear resistance so that the weight loss was obtained as 11 and 31 mg, respectively. Observation of the wear tracks of the coatings indicated that the lower wear rate of the CZ coating was attributed to its higher toughness and therefore filling the pores due to the higher plastic deformation of its wear debris.

The present study takes a descriptive-analytical approach and aims at explaining the causes and factors for Idrisids’ support of settlement and urbanization in northern Africa as well as investigating the most important measures they took in this regard. According to the findings of the study, the followings were the most important factors for the Idrisids’ support of settlement and urbanization: Creating security, political stability, and financial support in establishing government; specifying a capital; attracting, merging and settlement of various tribes in urban areas; choosing places and cities with strategic and geopolitical position against the Abazids and Safarids Khawarij as well as Banu-Madar and Bani-Rostam anti-Shiite governments; sighting important and strategic areas of far west and middle west; considering geographic and political issues, including distance, for better reaching to various regions of the north Africa; and supporting settled and urban groups against tribal forces of Khawarij. Thus, the followings are among the most important measures taken by Al Idris in this regard: establishing and building commercial-political cities such as Fas and settling different tribes; building mosques; minting coins; delivering sermons and holding meetings for lectures in squares and mosques; building workshops for oiling, tannery, and making soaps; supporting private ownership in cities; digging wells for water; buying lands; developing agriculture, gardens and urban areas.

Agricultural crops have damaged a lot due to the aftermath of late spring frost, and because low temperatures have damaging effects on agricultural production, it is essential to anticipate and prevent potential damages. Often, atmospheric temperatures variations are very urgent due to the ightemperature of the systems and the plants can not adapting themselves with severe oscillations and,consequently, have been damaged. identifying the sea level equations and the late spring freezing frost of the period from 1990 to 2015. This analyze has been done to determine the times of the freezing phenomenon, determine the minimum daily temperature of 7 stations placed in Kermanshah, Hamedan and Ilam. After analyzing the data of spring frost freezing of Kermanshah province using the main component analysis technique and hierarchical clustering method ,the most common 10 patterns of late spring coldness of the areawerestudied and determined. In 10 resulting cluster, the 8 clusters are related to the high pressure pattern of Siberia. From the total 91 days of spring frost freezing in Kermanshah province (79% (72 days)) is due to the high rainfall of Siberia, 12% (11 days) is due to the Mediterranean climate and 9% (8 days) is due to the Van lake climate.

Agricultural crops have damaged a lot due to the aftermath of late spring frost, and because low temperatures have damaging effects on agricultural production, it is essential to anticipate and prevent potential damages. Often, atmospheric temperature variations are very urgent due to the high temperature of the systems and the plants cannot adapt themselves with severe oscillations and, have been damaged. The aim of this study was to analyze the climate of the spring frost in Kermanshah, identifying the sea level equations and the late spring freezing frost of the period from 1990 to 2015. This survey has been done to determine the period of the freezing phenomenon, determine the minimum daily temperature of 7 stations placed in Kermanshah,  Hamedan, and Ilam. After analyzing the data of spring frost freezing of Kermanshah province using the main component analysis technique and hierarchical clustering method, the most common 10 patterns of late spring coldness of the area were studied and determined. In 10 resulting cluster, 8 clusters were related to the high-pressure pattern of Siberia. From the total 91 days of spring frost freezing in Kermanshah province (79% (72 days)) is due to the high rainfall of Siberia, 12% (11 days)  is due to the Mediterranean climate and 9% (8 days) is due to the Van lake climate. These pressure patterns were named according to the location of their deposition, which caused the loss of the environment and the freezing frost of the spring.

Early heat waves are extreme events that cause heavy losses in plant and animal life and cause many social and economic problems for communities. The purpose of this study was to identify synoptic patterns and statistical analysis of preterm heat waves in northwestern Iran. To do this, the maximum daily temperature data of March 14th was used for fourteen synoptic stations in the northwest of the country during the statistical period (1333-1393) Hijri Shamsi. Then, on the basis of the threshold, the Baldy index was selected for 61 days of heat wave. All statistical characteristics of the data were processed in SPSS software. They were The elevation data of the middle atmosphere of the atmosphere was extracted from a NCEP / NCAR database on a network with an arc 2/5 × 2/5 degree on the 0 to 70 degree eastern longitude and 0 to 60 degrees north latitude. The matrix was made up of 864 columns in 40 rows, with rows of days with thermal waves and elevation data on the columns on the middle of the atmosphere. The analysis of the basic components was performed on the algebraic data matrix matrix And 12 components that account for about 93 of the variations in pressure levels above 500 hp, were identified. To identify the coherent patterns, cluster analysis was performed on the scores of the components by the WARD integration method. Five types of pre-heat generation waveform patterns were identified. The results of this study showed that the premature heat waves in the northwest of Iran are due to high altitude formation in southern Arabia, the Aden valley and the center of Sudan at a level of 500 hpa and the formation of Sudan's low pressure in the sea level and the discharge of its tabs to the north and northeast of the region The case study (Northwest of Iran) also includes events occurring.

Cr2O3, YSZ and SiC nano-powders were prepared by ball milling and subsequently mixed and agglomerated to reach the proper composition and size for spraying. Morphological investigations and particle size analysis showed that powder particles after 5h of milling time reached to an ultrafine/nano size. The powder mixtures were then deposited onto 304L steel substrates using Atmospheric Plasma Spray (APS) to deposit Cr2O3-20vol%YSZ-10vol%SiC composite coating. Microstructure and morphology of the elemental/milled powders and plasma sprayed coatings were characterized using Field Emission scanning electron microscopy (FESEM) equipped by EDS. X-ray diffraction (XRD) patterns of powder particles and coatings included only the elemental peaks without any traces of impurities and new appearance peaks. Using image analysis method, the coatings porosity content increased from 8.7 to 12.8 through formation of composite coating. Also mechanical properties of the coatings including bonding strength, micro hardness and fracture toughness were evaluated. The results showed that coatings have high bonding strength of 40-49 MPa. Regarding hardness and toughness results, adding reinforcements to Cr2O3 coating increased hardness and toughness to 910 HV and 8.1 MPam1/2, respectively.

In this research, nanostructured Cr2O3 (C) and Cr2O3-20YSZ (CZ) coatings were deposited using Atmospheric Plasma Spray (APS) process and subsequently their mechanical properties including fracture toughness, hardness and bonding strength were evaluated and compared with each other. For this purpose, Cr2O3 and YSZ nano-powders were firstly prepared by high-energy planetary ball milling and then mixed in the given volume. To use the powder mixture in the plasma spraying, the powders were agglomerated and sprayed onto a 304L steel substrate. Microstructural studies of the powders and coatings were carried out through Filed Emission Scanning Electron Microscope (FE-SEM) equipped with Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD) analysis. XRD patterns of the milled powders and the coatings indicated there was no newly-appeared phase during the milling and plasma spraying process. Porosity of the coatings was measured using an optical microscope by image analysis of their cross-sectional images. Mechanical properties evaluation showed that both coatings have high adhesive strength in the range of 43-49 Mpa. Although the addition of YSZ nanoparticles to the chromia coating slightly decreased the coating hardness, it caused a considerable increase in the coating toughness due to the zirconia transformation toughening mechanism.

In the present work, Cr2O3 (C) and Cr2O3-YSZ (CZ) coating were produced using ball milling of the starting powders, mixing the milled powder, and subsequently atmospheric plasma spraying of the agglomerated powders on 304L steel substrate. The corrosion behavior of the coatings with and without sealing was evaluated by electrochemical potentiodynamic polarization and electrochemical impedance spectroscopy as well as immersion tests in a 3.5% NaCl solution. The results of microscopic image analysis showed that addition of YSZ to C coating caused an increase in coating porosity from 8.7% to 10.2% and a decrease in splats degree of flattening. Data obtained from electrochemical tests indicated the better corrosion resistance for individual Cr2O3 coating that was related to its denser microstructure. Sealing treatment by limiting electrolyte access to the substrate surface considerably increased the corrosion resistance (ohm.cm2) of the C and CZ coatings from 191 and 379 to 23189 and 77916, respectively.

studying and identifying the middle levels change affecting the formation of a circular pattern creation is inevitable. In this study, the annual rainfall data for selected stations Zab River Basin during the period 2015-1986 were the standard time. After indexing and spatial-temporal threshold, 184 days without rainfall were selected in the wet period of three severe drought in the region. Level 500 HP height data located in the range of 0 to 80 degrees northern latitude and eastern longitude on dry days as a matrix S_Mode were used and these data using principal component analysis were processed using modern statistical methods. Based on the correlation matrix, the main focus of the 500 HP topography of the basin dry days were identified and analyzed. The results show that, in the happening time of dry days, twelve atmospheric middle levels of height change focus have been effective. In this regard, the following two centers having the highest anomalies (R≥0.7) are detected according to the high levels of the atmosphere: 1) the center of Eurasia-Africa, 2) the center of West Africa, respectively, 48% and 10% of the total area of the study. Such changes in middle atmospheric levels cause to strengthen and deepen the traffic axis and on the ridges. In the meantime, the change of first center has the highest impact on creation of stability and domination of dryness in days of Zab River Basin.

Storm as one of the natural disasters has affected different regions and caused great economic, social, political and environmental losses. In this paper, after defining storm threshold, data of level 500 HPa height for 40 days of storm during the period (1986-2011) were processed using an advanced factor analysis. And finally, based on the correlation matrix (variance-covariance) and Varmix rotation on the factors, major topography variation centers at 500 hPa that affect heavy storms at Zab River Basin were discovered and analyzed. The results show that, eight centers have been involved in occurrence of storms. Among these eight centers, four centers that have the highest anomalies (R>0.7) at 500 HPa height, are detectable. 1) Axis of Middle East - North Africa to Northern Russia. 2) African tropical areas-Indian Ocean. 3) North Asia-North Europe. 4) The Scandinavian region. Such changes would strengthen and deepen the axis of ridges in these regions at 500 hPa level, and consequently synoptic storm patterns are created. Meanwhile, changes in the first 500 HPa at the first center (Axis of Middle East - North Africa to Northern Russia), have the most influence on the development of storms in Zab River Basin.

The aim of this study was to assess the suitability of fertile soils to grow and increase in production of sugar beet cultivation and Rural Development is using AHP and GIS. For this purpose, digital data layers annual rainfall, growing season precipitation, annual temperature, growing season temperatures, temperature germination period, topographical map layers, altitude, slope, aspect and soil type, vegetation, land use, rural areas and roads were collected. By using AHP weighting, was carried out with the aid of digital map layers Overlay function in ArcGIS, map layers were combined and analyzed. The results showed that, although 18% of the total land area suitable for sugar beet cultivation and are in very good condition, but if proper utilization of soil and water resources can play an important role in the stabilization and reduction of rural migration.

Iranian culture and literature originate from religious beliefs that deeply connect with Iranian people’s emotions toward innocent fellows especially Imam Reza as well as Iranian culture and folklore literature. The analysis of symbolic customs and Imam Reza’s literature custom in parallel with his personality enrich our beliefs. The symbolic customs and Razavi folklore literature result in; following, identification, coherence, cohesion, decrease in the extent of routine life, the production of hope and happiness in the contemporary age due to educational factors as well as self-confidence, because these factors play an important role in the young ages .This essay is based on context analysis, it examines the symbolic customs including heroic poems to set up flag, to tie scarf, oblation, setting off, souvenir besides folklore literature which includes Lullaby, premium, mourning, sound, people’s tools which are influenced by Razavi culture. It has shown Imam Reza’s personality, his well-known features in Iranian culture and folklore literature.

The aim of this study is to analyze the synoptic situation of severe storms of Zab basin. Daily data of wind speed, over the period 1364/01/01 to 1390/12/29 (9861 days) from three synoptic stations, was taken from the department of meteorology. Given the scale of temporal and spatial distribution, through threshold size of wind speed and comprehensiveness as well as calculation of the 90th percentile of the wind speed, 40 days of pervasive and severe storms were selected. Sea level pressure data on the network with a size 2.5° × 2.5° that was located on 00-80 degrees east longitude and 00-80 degrees northern latitude from the database NCEP/NCAR were extracted. A Matrix was formed in the dimensions of 864 columns in 40 rows on rows of days with stormy days on the rows and elevation data middle levels of the atmosphere, on the columns. A principal component analysis was performed on data matrix elevation and six factors were identified that about 97/4% of the Pressure elevation changes of 500hp level was explained. To identify synoptic patterns, cluster analysis integration "wards" was performed on these components. The results showed that the storms happen frequently during spring and autumn. April was the most prevalent (33%) and July and August had the lowest number of storms. Five synoptic patterns of atmospheric middle level, in the form of three major causes of severe storms in the Zab River Basin: Cut off low pattern, Shallow trough pattern of long wave and deep trough pattern of short wave. In these between, cut off low synoptic pattern of the upper atmosphere with an abundance of 47.5 percent in May and December had the highest frequency. Irregularities in the movement and position of the polar vortex caused the jet stream and storm paths meridional winds to have greater control and troughs to be driven deeper towards the low latitudes. Because of the special arrangement of relatively strong and contrasting surface synoptic, the pressure gradient and energy exchange at its maximum reached compression Isobaric lines and as a result, strong winds in the catchment area level have been created. The winds blow, almost in all identified patterns, from the west and southwest.