فهرست مطالب محمد رضوانی

The aim of the present study was to investigate the possibility of aggregating and estimating the collective demand function for meat commodity groups (mutton, beef, poultry, canned fish, southern fish and northern fish) using Weak Separability methods, generalized composite commodity and the demand function of Iranian urban households. Necessary data and information were obtained from the annual statistics of expenses and income of Iranian households of the Statistics Organization for the period of 2005-2020. The results of income elasticity showed that two canned goods, fish and southern fish, are considered luxury for Iranian urban households. Northern fish with a self-price pull of -1.28 is most sensitive to price changes against other types of meat. Also, canned fish and southern fish are substituted based on the intersection of canned fish. According to the results of the Separability test for different types of meat, different types of meat can be divided into two groups of red and white meat.

Examining the behavior of consumers of various types of consumer goods in relation to the changes of different price and non-price factors and the effect of each of these factors on demand is considered as one of the important economic issues. Estimating the demand function and calculating the elasticities of different groups of goods is one of the most important tools for investigating consumer behavior to know his preferences, and any policy and planning related to consumption requires analyzing the consumption pattern of households and knowing the position of each group of goods in the household budget. The large number of products and the lack of availability of sufficient information about consumer behavior make analyzing their behavior difficult. Aggregation goods and use of composite commodity are considered as an effective solution to deal with issues such as the unavailability of detailed information of each item, heavy costs of data collection, the presence of missing observations, the occurrence of collinearity problems, and the limitation of degrees of freedom by researchers. But it is important that the grouping is done correctly and consistently, because incorrect grouping appears as a specification error in the demand system and affects the extent of estimated parameters and elasticities as well as the test of the assumptions of demand functions, the result of which is presenting a false picture of consumer behavior and creating deviations in policies. Therefore, with respect to the importance of grouping and aggregation of different goods, this study aimed at investigating the conditions of aggregation of animal protein products including red meat, fish, chicken, milk and eggs using the methods of weak separability and generalized composite commodity for Iranian households in the period of 2004-2021. The hypothesis of the research in the method of weak separability was that in the group of animal protein products, the products of three groups of meat (red meat, fish and chicken), milk and eggs could be identified as three composite groups and then, the above three groups considered as one composite group with the name of the group of animal protein products; also, the hypothesis that red meat, fish, chicken, milk and egg products could be specified as a composite group was tested using the generalized composite commodity method. In the present study, the Quadratic Almost Ideal Demand System (QUAIDS) was used to investigate the weak separability. The results of the adjusted Wald statistic related to weak separability showed that the product group of animal protein products (red meat, fish, chicken, milk and eggs) could be separated into three groups: meat, milk and eggs. In fact, the result of the test did not reject the assumption that consumers first would allocate a part of their expenses to the group of edible goods regardless of its type; then, the act of allocation between different types of groups of edible goods would be done based on their prices. The study results indicated that the red meat and fish were found to be luxury goods while chicken, eggs and milk were known as essential goods for Iranian households. Own-price elasticities of all types of animal protein products were negative according to theoretical expectations based on the maximization of consumer utility. The highest absolute value of own-price elasticity was related to the red meat (-2.44), which shows that the consumption of red meat is very sensitive to price changes. The lowest absolute value of own-price elasticity was related to the eggs (-0.40). Following an increase in prices of commodities, their demand does not decrease significantly. The absolute value of the elasticity of the price of fish and chicken also shows the sensitivity of the consumption of fish and chicken to price changes, so if the goal is to increase consumption, the price reduction policy can be effective.  Due to the high cross elasticity coefficients of the demand for the red meat and chicken as well as the fish and red meat, it can be expected that following the change in the price of red meat, the demand for the chicken meat and the change in the price of the fish meat will significantly change the demand for the red meat. Therefore, in the application of optimal demand management and consumption pattern planning, the use of proxy product price policies can be effective.

Hard tissues in the body consist of intricate three-dimensional composites, wherein approximately 30% constitutes collagen fibers, 60% mineral reinforcing particles, and 10% water. The mineral copounds of Natural bone tissues, such as calcium phosphate materials play a fundamental role in enhancing strength,hardness, and pressure resilience. The use of calcium phosphate bioceramics as bone grafts, such as Whitlockite(Ca18Mg2(HPO4)2(PO4)12), offers a promising method for treating bone defects due to its close chemical, biological, and crystalline resemblance to natural hard tissue. Also, Its biocompatibility, functionality, stability under acidic pH, negative surface charge, osteo inductivity and osteo conductivity, and maintaining Mg ions in their crystal structure make it an ideal bone substitute as compared to the other Ca-P bio ceramics.
This study aims to synthesize Whitlockite nanopowders using the chemical precipitation method with the precursers Mg(OH)2, Ca(OH)2, and H3PO4, and investigate the effects of pH, temperature, and Ca/Mg and Ca/P ions  ratios on the synthesized Whitlockite. Additionally, the impact of varying temperature and pH on the reactions during Whitlockite synthesis is explored. To characterize the synthesized powders, XRD, FTIR, SEM, and EDS analyses were employed. The results revealed that optimizing pH to 5 and temperature to 80°C yielded  Whitlockite with a crystal grain size of 61 nm. Increasing the ratio of (Mg2+ / Ca2+) ions concentrations in the reaction solution resulted in the formation of the Whitlockite phase and the magnesium phosphate phase (MgHPO4), while decreasing that ratio produced the monetite phase (CaHPO4) or dicalcium phosphate dihydrate (CaHPO4.2(H2O)). Furthermore, at 70°C, the formation of hydroxyapatite initially occurred, however the reaction favored the transformation into the more stable Whitlockite phase as pH values became acidic. In conclusion, this research highlights the significance of chemical precipitation for Whitlockite synthesis, providing valuable insights into the influence of pH, temperature, and ion ratios on the resulting crystalline phases. The findings contribute to a deeper understanding of the potential applications of Whitlockite as a bioceramic material for bone defects treatment.

Stable photoluminescence is a phenomenon that is excited by irradiating high-energy light (usually ultraviolet light and sometimes beta rays) to a given substance. After the excitation stops, visible light is emitted from the excited electron states. The material will be done for a time that can be evaluated from seconds to several hours.In the present research, in the first stage, the synthesis of SrAl2O4 with stoichiometric percentages was investigated by solid-state reaction method at temperatures of 900, 1100, 1300, and 1500 ℃. Then, Dy2O3 and Y2O3 additives were added to the SrAl2O4 mixture with ratios of 1 to 4% by weight. The crystal structure and network of the SrAl2O4 host were determined by X-ray diffraction (XRD) analysis. The emission intensity of the mentioned factors was investigated by photoluminescence spectrophotometry (PL) with radiation at the wavelength of 237 nm, and the emission obtained in the wavelength range of 500-540 nm in the sample with different additives. Also, Fourier Transform Infrared Spectroscopy (FTIR) of the host composition and optimized samples with additives were also performed. The microstructure of the synthesized particles was examined using a scanning electron microscope (SEM).

In this research the effect of planting date and Bentazon application on control of weeds, and soybean yield was investigated.

Methods and Materials:

 Experiment conducted as split plot in a randomized complete block design with 4 replicates. Mainfactor included five planting dates (20 April, 4 May, 18 May, 2 June and 16 June) and subfactor was herbicide application including without and with bentazone application.

Delay in planting date and herbicide application, wild melon, and black nightshade control increased both at 10 and 30 days after spraying. The late planting date reduced soybean economic (29.2%) and biological yield (41.1%). Delay in planting date reduced the biomass of wild melon (99%) and black nightshade (61%) and other weeds (82%). Herbicide application decreased the biomass of wild melon (51%) and black nightshade (92%) and other weeds (71%). Soybean yield in early planting date was higher (71%) than late planting date. In the late planting date, density of wild melon and black nightshade was lower than early planting date. Delay in planting date accelerated flowering, and reduced ripening period, seed production, and yield.

The early planting date of soybean along with the application of bentazone reduces weed growth, crop damage and increases soybean yield that can be recommended to farmers.

Two species of common cocklebur (Xanthium strumarium L.) and spiny cocklebur (X. spinosum) are common annual summer weeds in soybean fields and other summer crops. The current research was carried out with the aim of determining the cardinal temperatures of germination and determining the phenology stages of these two species in Sari University of Agricultural Sciences and Natural Resources. In order to determine the cardinal temperatures of germination of seeds of two weed species, the seeds were examined at constant temperatures of 5 to 45 °C in a completely randomized design in 4 replications in a laboratory experiment. Also, the phenology stages of two weed species were investigated in a field experiment. The highest germination% was observed for the spiny cocklebur (51.3%) and the common cocklebur (58.1%) at temperatures of 25 and 35 °C, respectively. According to the different parameters of segmented model, the base temperature, lower optimum temperature and ceiling temperature for spiny cocklebur are 1.4, 23.2 and 54.7 °C, and for common cocklebur are 4.8, 34.6 and 48.4 °C, respectively. Time from emergence to physiological maturity for the spiny cocklebur and common cocklebur were 136 and 128 days, respectively. The results suggested that seed germination of the two weed species occurs in a wide range of temperatures, i.e. of 5 to 45 °C, and the best time to control this weed is late summer (before the beginning of the flowering stage).

  it is important to correctly estimate income and price elasticities and the impact of economic sanctions on the consumption behavior of Iranian households. So, the purpose of this paper is to investigate the consumption behavior of urban households in Iran by applying the quadratic almost ideal demand system (QUAIDS). Also, the existence of structural failure in the consumption basket preferences of tea, sugar, and sugar of urban households has been investigated using the parametric approach and the switching regression framework developed by Ohtani and Katayama (1986) from 1998 to 2022.The price elasticity of various types of tea, sugar, and sugar has increased after sanctions and Iranian and foreign tea, sugar and sugar have changed from non-elastic products to products with elasticity. The increase in price elasticities shows that with the increase in prices and inflation in the years after the sanctions, the sensitivity of consumers to price changes has increased. Therefore, considering the elasticity of the high price of products after the sanctions, it will be the right decision to use price tools to protect consumers.

In order to assess the competitive ability of soybean with P. alkekengi, a test was conducted at sari Agricultural Sciences and Natural Resources University. This research was carried out in two greenhouse and field condition. The treatments consisted of five planting ratios of soybean and P. alkekengi including: 25:75 (soybean - weed), 50:50 (soybean - weed), 75:25 (soybean - weed) and pure (100% soybean and weed species). According to the results the maximum yield of soybean in pot (39.60 g plant-1) and field conditions the maximum yield of soybean (141.44 g m-2) were obtained in weed-free conditions (soybean monoculture) and increasing soybean density reduce P. alkekengi biomass than the monoculture of this weeds. In pot and field conditions, the highest pod number per plant (171.66 and 201, respectively) and 100- seed weight (18.45 and 17.85 g, respectively) were observed in pure soybean (weed-free) cultivation. Also soybean tolerance to different densities of P. alkekengi showed that soybean can tolerate low density (25 percent) of P. alkekengi. Also study the competitiveness index (CI) showed that soybean at low density of physalis was higher and inhibit the weed biomass increment. The results showed that soybeans had a higher tolerance index and competitiveness index than the P. alkekengi. In general, increasing the density of P. alkekengi reduced the yield and yield components of soybeans in both potted and field conditions. In general, soybeans in low densities of P. alkekengi had a higher competitive ability than this species and inhibit the increase of weed biomass.

Treatment and repair of bone defects, has been a major challenge for bone regeneration activists for a long time. In treating bone defects, using a proper bone graft is essential. Among various kinds of bone grafts, bio ceramics alloplastic grafts are considered, owing to their excellent non-toxicity, non- allergenicity, anti-inflammatory, biocompatibility and bio-functionality. The bio-ceramics like Whitlockite (WH: Ca18Mg2(HPO4)2(PO4)12) possess same chemical, structural and biological properties with human bones, have been widely used as bone substitutes. It is the second most abundant mineral in living bone, which can contain 26-58 wt% of bone tissues. In this study, we investigated the biocompatibility, bioactivity and biodegradability of Whitlockite nano powders, by immersing samples in Simulated Body Fluid (SBF) for 3,7,14 and 21 days. The obtained samples were characterized using X-ray Diffraction (XRD), Fourier transform infared spectroscopy (FT-IR) and inductively coupled plasma -optical emission spectrometry (ICP-OES).  Results indicated that, WH nano powders had significantly biocompatibility and biodegradability due to formation of Ca3(PO4)2 , (Ca, Mg)3(PO4)2 and Whitlockite on surface of WH samples. Additionally, the WH nano powders exhibited excellent mineralization ability in vitro with continuously released Ca2+, Mg2+ and HPO42- when immersed in (SBF). Furthermore, the pH changes of both samples were in the range of natural biological pH of the human body, which indicates the appropriate biocompatibility of the samples. However, the stability of whitlockite in SBF is at the highest level in 4<ph<5.< span=""> The results of the ICP analysis of the raw Whitlockite sample showed that about 150 ppm of magnesium ions are released from Whitlockite inside the Simulated Body Fluid during 21 days of immersion, which can provide a part of the body's daily magnesium needs. Also, by examining the weight changes of the samples within the SBF, it will be seen that the weight loss rate of the raw whitlockite sample is concerning 32.11% quite the heat treated whitlockite sample, which indicates the upper biodegradability.</ph<5.<>

This paper examines the security risks and challenges associated with energy sources for ships, including increasing fuel prices, tightening international pollution laws, and limited space and fuel on board. With the rise of modern naval warfare and technological advances, energy production for vessels has become a strategic priority. This study focuses on identifying threats in electricity generation for ships and investigates the reliability and availability of various energy production systems. Using a Markov model, the study compares different energy production systems by considering their advantages and disadvantages, influential factors, and level of reliability and availability. Results show that the use of solar energy in combination with diesel generators has the highest reliability (0.988) and availability (0.997) compared to other production sources. The study demonstrates that solar energy can be used to meet a portion of the ship's power consumption needs, reduce maintenance and repair costs, extend the life of generators, increase the duration of navigation, ensure continuity of energy supply, and improve passive defense in the field of electrical energy for marine vessels.

Spin-coating of Chalcogenide glasses is a cost-effective and flexible method to produce thin films applicable in photonics. In this paper Er was doped into Ga1As39S60 glass by melt quenching technique and solutions for spin coating were prepared from glass powders dissolved in Propylamine and Ethylendiamine. Substrates used were microscopic slides (refractive index of about 1.51). Applied layers were dried in 60 ℃  vacume for 60 min and then heat treated at 150 ℃  for 60 min in Nitrogen Atmosphere. Influence of solvent type on optical parameters of films and the amount of residual solvent was studied by examining UV visible infrared spectroscopy. According to AFM images, surface roughness of layers was about 3.3-3.5 nm. Although films demonstrated PL emission at 1.55 µm, emission intensity was higher at the films deposited from PA solvent. EDS mapping images showed no clusters of Er within the glass matrix.

Redroot pigweed (Amaranthus retroflexus L.) is a noxious and cosmopolitan weed that is widely distributed in different parts of the world and competes severely with crops and reduces their growth and yield. The present study was conducted to investigate the effect of drought stress on some morphological and physiological characteristics of redroot pigweed in 2018 and 2019. Treatments included different degrees of drought stress with 5 levels including 100, 75, 50, 25, and 12.5% ​​of pot water content (equivalent to no stress, light stress, moderate stress, high stress, and severe stress). Leaf number, plant height, and leaf dry weight were affected by the interaction of drought stress×years and with increasing drought stress, leaf number, plant height, and leaf dry weight decreased in both years of the experiment. With decreasing the water content of the pot, the activity of catalase and superoxide dismutase increased. The highest levels of catalase and superoxide dismutase activity (110.35 and 1433.33 units of enzyme/mg protein per minute) were observed in the second year under severe stress, respectively. Increasing the intensity of stress decreased the soluble protein content of the plant. Also, drought stress reduced plant chlorophylls a and b content, whereas, carotenoid content increased. The highest amount of carotenoids was observed in both years under severe drought stress conditions. Overall, drought stress in the second year reduced growth in redroot pigweed further but in this year, the enzyme activity ramped up further. Therefore, this plant can modify stresses and maintain its survival by changing its biochemical activity.

Due to the limited space of the military vessel, rising fuel prices, the intensification of international laws on pollution, carbon dioxide emissions, as well as the acceptable availability of solar energy on board, the use of new technologies such as the use of solar energy can significantly It can be used to provide part of the power of consumers in ships.The purpose of this paper is to design and simulate the supply of part of the power in the ship using solar energy as a complementary energy source to reduce fuel consumption, increase reliability, longer life at sea and increase ship space. In this regard, according to the hypothetical floating shape, the solar panels on the roof of the helicopter hangar, which has the highest loss of solar energy, have been feasibility and installed.The solar system is designed according to the roof area of ​​the helicopter hangar and can be used to supply electricity for lighting, three-phase and single-phase pumps, refrigerators and refrigerators, as an emergency or in parallel with the floating power supply network. The calculations in this paper are performed as mathematical relations and are simulated with pv syst software. The results show that the use of solar energy, in addition to providing 25% of the consumption of military floating power, can reduce maintenance and repairs, reduce costs, increase the life of generators and increase the duration of navigation.

With the increasing use of solar energy and its many benefits, the use of this new energy in ships has been considered.One of the ways to increase the reliability of the ship is to have a suitable power in all weather conditions of the sea, and naturally in the photovoltaic system, to maximize the energy that can be received from them per kilowatt of power is installed, because the voltage characteristic Solar cell flow is strongly dependent on radiation and cell temperature. On the other hand, load changes also change the operating point and cause deviation from the maximum power point. Therefore, in various articles, much attention has been paid to maximum power methods in photovoltaic systems.In this paper, a new strategy for tracking the maximum power point by feed-in method is proposed, relying on the capabilities of the neural network to use this energy at sea. The feeder approach prevents noise propagation in the network because it is forward and has no feedback. The previous methods do not have the ability to accurately track the maximum power point in the event of turbulence or sudden changes in sunlight. Solar vessels change abruptly, have applications that improve its performance, and simulation and performance results show that the maximum power is received in this method.

 Plant development is defined as a series of phenological events that are controlled by external factors and determine changes in the shape or function of some organs. Temperature and photoperiod are two of the most important environmental factors affecting phenological development. Papaver rhoeas L. and Papaver dubium L., from the Papaveraceae family, are common annual winter weeds in northern Iran. The life cycle of these species is closely related to winter crops such as wheat (Triticum aestivum L.) and other winter cereals that compete severely with them. The Papaver species are capable of producing a huge amount of small-sized seeds that remain dormant at maturity. The timing of emergence, growth and sexual reproduction is highly important for the success of invasive weeds. Checking the phonological behavior of these plant species along with their seed production would be useful for decision-support systems helping managers select the best management strategies and, thereby, improving P. rhoeas and P. dubium control. Also, the phenology data would allow predicting these species invasibility of new areas. The present study was aimed to quantify the phonological behavior of these weeds.
 In the present study, the phenology of P. rhoeas and P. dubium were studied in the research field at Agricultural Sciences and Natural Resources University of Sari, Iran, with an annual rainfall of 851 mm per year. Seeds of these species were collected from a wheat field located in Mazandaran province, north of Iran during spring 2018. These species seeds were cultivated on 12 November 2018. The phenological stages were recorded from emergence to the end of the seeding stage. The phenology was studied based on the growing degree day. At the end of the experiment, the period of each phenological stage was calculated based on the day and the growing degree day. In order to determine the morphological traits of the plant, eight sampling steps were performed. Morphological traits such as plant height, number of leaves, number of flowers, number of capsules, and dry matter were measured.
 The results showed that P. rhoeas and P. dubium grow from 0 to 1723.56 and 1759.06 growth degrees day, respectively. During this period, seven phenological stages were recorded for these two species. These stages were included emergence, rosette (7-8 leaves), stem elongation and branching, blooming, flowering, fruiting, and seed maturity. The flowering stage period in both species was long, 48 days in P. dubium and 46 days in P. rhoeas. The results showed that the shortest and longest stages of development of these two weeds were emergence and stem elongation, respectively. In this study, the growth period of P. rhoeas and P. dubium took about eight months. It has some variation with regard to height, the number of flower, number of capsule and dry matter between both species under the same environmental conditions but both plants started their developmental stages at the same time and finished at almost the same rate. The trend of changes in height, number of leaves, number of flowers, number of capsules, and dry matter were similar in both species. The life cycle of these two species begins with germination in autumn and ends with seed production in late June. The longest period of growth stage in both species was in spring and this trend decreases in late spring. The flowering stage begins in late March and ends in mid-June. The maturity period of these two species was from mid-June to the end of the first decade of July. One of the characteristics of these two species is high seed production. In P. rhoeas, at the end of the fruiting stage, each plant produced an average of 13 capsules and each plant produced an average of 5000 seeds. Also, in P. dubium, each plant produced an average of 14 capsules, and each plant of this species produces an average of 5922 seeds.
 Based on knowledge of the different phenological stages of the two species, it is possible to plan for proper management. From a managerial point of view, these two species should be controlled before the blooming stage; so that their seeds do not enter the seed bank, because their seeds are considered as causes of contamination in the field.

Renewable energies outfitted with low latency assets as wind turbines and photovoltaic exhibits give significant adverse consequences through power framework dynamic protections. For this issue, in view of fostering a high voltage direct current (HVDC) interface, a versatile Neuro-Fuzzy-based damping regulator is introduced in this paper for working on unique execution of low inertia resources associated with power frameworks. The created power framework comprises of various age sources including seaward and inland wind turbines (WTs), photovoltaic exhibits (PVs) and limited doubly fed induction generators (DFIGs) which are incorporated together through an interconnected framework. For this situation, thinking about various functional and innovative conditions, damping execution of proposed ANFIS plot is assessed. The proposed plot is a non-model-based regulator which utilizes the benefits of both neural and fluffy rationales together for giving a quick and secure design of damping regulator through continuous recreations. To research ANFIS plot through genuine cases, considering a commonplace microgrid comprises of various low-latency assets (for example WT, PV, DFIG), the framework damping exhibitions through hamper occasions are assessed. Recreation results demonstrate viability and effectiveness of the proposed plot for damping dynamic motions of low inertia resources with high damping proportions with respect to extreme issue occasions.

 Various studies have shown that changes in rainfall due to climate change can affect the stability of food supply and in fact climate change by increasing the prevalence and severity of drought or flood, crop yields, food access and also effect food prices. According to the FAO, Iran's food security rank is 82 out of 125 countries in the world, and one of the reasons for this rank is the excessive waste of agricultural products in Iran. As a result, citing a wide range of previous studies, it has been documented that the impact of climate change on food security for countries that are more dependent on agriculture is largely negative and has significant effects. Therefore, in present study, citing theoretical foundations and foreign and domestic studies conducted in the field of food security especially in Iran, factors such as food prices, climate change, household income, exchange rate and targeted subsidy policy as factors affecting selected food security and their effect on food security of urban households in Iran were studied.

 In this study, it was our goal to find the effects of food price variables, climate change, household income, exchange rate and targeted subsidy policy on food availability by estimating single equations of the food security index.In this study, based on the subject literature and available information, the self-explanatory model with wide intervals (ARDL) and the error correction model (ECM) introduced by boys and colleagues have been used to examine integration and estimate short-term and long-term relationships between variables. Data required for the present study, regarding the open market exchange rate and food prices (food and beverages) from official statistics based on the annual reports of the Central Bank of the Islamic Republic of Iran and the necessary information to calculate the food security index of households and average household income from detailed results Expenditure and income of urban households of the Statistics Center of Iran, for the period 1398-1399 has been extracted.

 The results showed that in the long run, a one percent increase in food prices reduces the food security index of Iranian urban households by 21 percent. As expected, the coefficient of variable climate change has a negative and significant effect on the food security index, and with its increase, the production of food and agricultural products decreases, and as a result, the food security index decreases. The growth rate of free market exchange rate with a negative sign at the level of one percent is significant. Since the agricultural industry in Iran is an industry highly dependent on imports. As a result, the increase in the exchange rate increases the price of agricultural products and affects food security. Annual household income has a positive and significant effect on household food security index. By increasing household income and assuming its appropriate distribution in society, it can be concluded that urban households are faced with increased purchasing power and ability to meet their food needs, and this variable has a positive effect on energy status and food security. The virtual variable of the years of implementation of the law on targeted subsidies is also significant at the level of 10% with a negative sign. The results show that in the long run, the implementation of this law has reduced the activity of farmers due to rising prices of agricultural inputs and energy carriers, this issue leads to a decrease in domestic food production and thus increases their prices and ultimately reduces food security of households. The estimated coefficient of ecm (-1) is equal to the negative value of 0.42 and is statistically significant at 1% probability level. The value of this coefficient indicates that each year 0.42% of the imbalance of one period of food security of urban households in Iran in the next period is adjusted.

 Given the negative effect of food price index and exchange rate on food security of urban households, the application of appropriate exchange rate policies can be very effective in reducing inflation, especially food price inflation, which threatens the country's food security. With increasing investment, domestic food production is approaching self-sufficiency in this sector, in which case food prices will be subject to domestic supply and demand, and to some extent will be protected from exchange rate fluctuations and food imports, and this will create food security and prosperity. The economy in the country will help a lot. Given the negative effect of targeted subsidies, a review of the implementation of targeted subsidies policy to establish food security for households is proposed. To reduce the negative effects of climate change on food security, selective strategies must focus on addressing the adverse effects of climate change and food insecurity. Educating and strengthening public belief in climate change and water crisis, formulating long-term and short-term plans and policies for water resources management under climate change conditions with the participation of all relevant organizations and moving towards modern methods can be effective in reducing the effects of climate change.

Western sanctions against the Russian Federation and the Russian Federation's retaliation in 2014 and sanctions on food imports from the West, including the European Union, the United States, Australia, Canada and Norway, suggest that there may be changes in Russian consumers' preferences for cucumber. Imported from Iran has occurred. The present study tests this hypothesis using a nonparametric method based on the Generalized Axiom of Revealed Preferences (GARP). In this regard, price and quantity data related to the import of Russian Federation cucumbers from Iran and the countries that had the most exports of this product to Russia (Turkey and China); Reviewed for the period 2017-2000. The results of the study show that a significant structural change in the preferences of Russian consumers occurred in 2003 in favor of Iranian cucumber, which indicates the stability and loyalty of Russian consumers to cucumbers imported from Iran. Finally, the political disputes between the Russian Federation and Turkey have provided a good opportunity to develop the export of Iranian products in the market of the Russian Federation. Ensuring the production of quality cucumbers throughout the year and not changing government policies on exports can help increase Iran's share of the Russian Federation market.

Chitgar park with an area of 54000 hectares including heights is limited to the chitgar land to the north, from the south to the Tehran-karaj freeway, from the west to azadshahr and pykanshahr and from the east to the rabbit area of the valley is limited and with an area of about 950 hectares of land plowed, of the largest forest parks and tourist hub of Tehran province is considered. Evaluating the ecological capability of areas for ecotourism known as a means to achieve this goal.

Regarding the ecological characteristics of the area, environmental assessment of Chitgar Park for a central outing using a hierarchical analysis process was performed. First by reviewing various sources criteria and sub criteria are selected, then, using the paired comparison questionnaire weigth of criteria and sub-criteria were determined and used from the hierarchical analysis process to measure the criteria.

Maps were prepared for the specified factors and according to the given weights in the paired comparision questionnaire weight maps were also prepared, then the map of concentrated recreation entertainment was classified and the area of each floor was determined.

Power assessment was made according to the weigth assigned to the central recreation expertchoice 11 were used to weigth the criteria and ArcGIS 10.5 software was used to analyze the layers. Based on the results, about 80% of the area is concentrated on the central reflexion.

Atrazine is one of the most important herbicides in the world and Iran, which has high stability and is likely to contaminate runoff and groundwater resources. The aim of this experiment was to determine the most sensitive of the eight plant species to atrazine and to measure the leaching front of this herbicide.

The first experiment did in order to sensitivity assessment of eight plant species (Canola, Soybean, Ryegrass, Wild Oat, Wheat, Canarygrass, Redroot Pigweed, and Corn) to simulated atrazine residues by GR50 index (the required dose of herbicide to reduce plant growth by 50% ) at 2019. The second experiment was conducted to determine leaching front of atrazine. Levels of atrazine treatments were: control, usual dose (1.25 kg.h-1) and high dose (2.5 kg.h-1). The treatments were injected into soil columns in 32 cm height PVC pipes and after three days, all 2 cm pieces of soil columns were exposed to bioassay and chemical analysis, simultaneously.In the first experiment probit regression analysis was used to identify the most atrazine-sensitive species and in second experiment with completely randomized basic design the data were investigated by regression analysis.

First experiment showed that canola was more susceptible to atrazine compared to other species. Evaluation of canola seedling weight profile and atrazine concentration simultaneously at different depths of soil showed that atrazine penetrated to 10 cm depth.

It seems that atrazine accumulation to 10 cm depth is related to higher organic matter and clay content. Due to the fact that the maximum weed seed bank was located in the surface layers of the soil, application of atrazine herbicide in this field can increase the efficiency of weed control.

Competition for resources among plants has long been considered to generate stress for plants and to be important for determining the distribution of species, as well as their evolution. Competition can occur among the organs of a plant (intra plant competition), or negative interactions between the plants of a species (intra specific competition) or interference among different plant species (inter specific competition). Weeds have long been considered as the main competitor of crop plants. These plants can be problematic due to competition with crop plants over light, water and nutrients, decreases the quantity and quality of the product and the creation of a suitable refuge for insects and pathogens. The presence of weeds in soybean reduces seed yield and the rate of this decrease depends on weed density and stage growth stage. In agriculture areas, crop density is kept constant whereas weed density varies in accordance to local infestation degree. Therefore, variation in plant proportion of crops and weeds is established. Thus, in competition studies, it is important to measure the influence of plant density on the competitive process as well as the variation in plant proportion. There are several methodologies used to study plant competition. However, most researchers measured just the interference of weeds on crop growth and production without concerning about the competition process. Thus, it is important to use appropriate experimental designs and methods of analysis to understand the competition process not just by quantifying crop losses but in a mechanistic way. Replacement series experiments allow the control of plant density and proportion, where plant density is kept constant while plant proportion is changed for both studied species. This study aimed to investigate the response of soybeans to the interaction of three species of foxtail (Setaria glauca, S. verticillata and S. viridis) and competitions between the species of these three weeds.

These pot experiments were carried out at Sari Agricultural Sciences and Natural Resources University based on a completely randomized design in three replications. The first experimental treatments included planting ratios: 25:75, 50:50, 75:25 (soybean-weed) and pure stand of soybean and weed and in the other three experiments, each of the weeds compared in pairs with the ratios listed above. Density of soybean and weed in the sole stand was four plants per pot and in the planting ratio of 50:05 soybean-weed, two plants were considered from each plant. Also, in the planting ratio of 75:25 soybean and weed, 4 seeds were cultivated in each pot, wherein planting ratio of 75% three seeds of soybean or weed and planting ratio of 25% one seed of soybean or weed was planted. The traits studied in this experiment included seed yield, number of sub-branches, number of pods per plant, number of seeds per pod and 100- seed weight of soybeans. Weed biomass, height, number of leaves, number of spikes and number of tillers of weeds were also calculated in competition with each other. In addition, the ability of weed competition and the competition index were determined.

The results showed that the competitive ability of three species with soybean showed that the maximum soybean seed yield (15.56 g plant-1) were obtained in weed-free conditions (soybean monoculture) and increasing soybean density in interference with three species of foxtail reduce weeds biomass compare to the monoculture of weed. Although, survey competitive withstand ability of soybean to different densities of three species of foxtail showed that soybean is more tolerant to low densities (25%) of S. glauca, S. verticillata and S. viridis, but the competitive ability of soybeans compared to these three species was S. glauca > S. verticillata > S. viridis; because the increasing density of S. glauca, caused decreasing soybean yield with a gentle slope while, increasing density of S. viridis, made a decrement of soybean yield with a steep slope. The competitive ability of three species of foxtail together showed that increasing density of any species will diminished the growth index of other species when maximum height, tiller number, leaf number, spike number and biomass of all three species was observed in their monoculture.

The results of the competition of all three species of terns with each other show that inter-species competition has been more effective in reducing weed population life than the intra-species competition; Thus, S. viridis species could have a greater decreasing effect on S. verticillata and S. glauca species by creating more height, more tillers and leaves and as a result higher biomass production. So, the competitiveness between the three species was S. glauca <S. verticillata <S. viridis. According to the findings of the present study, by increasing the density of soybeans, weeds can be managed, especially in their low densities.

Consumer behavior and preferences among households’ milk may be in different time periods, different. It is important to change behavior in the studied time period specified by identifying changes in people's behavior, can be used to evaluate policy payments made or implemented new policies. The purpose of this study was to investigate the structural stability or break of Iranian consumers’ preferences for pasteurized and non-pasteurized milk. In this regard, using the cost and income statistics of urban and rural households’ in Iran Statistics Center in the period 1990-2016. Also to analyze household preferences, from a non-parametric pre-disclosed test (WARP) and Kruskal-Wallis statistics (K-W) have been used to distinguish permanent structural changes from fleeting shocks. For this purpose, the matrix of poorly expressed preferences was compiled using the average price and quantity of pasteurized and non-pasteurized milk in urban and rural areas, and by comparing consumer choices in different time periods. The results of the WARP matrix indicate a contradiction in the preferences of consumers of both pasteurized and non-pasteurized milk. In other words, the rational behavior of consumers of pasteurized milk and non-pasteurized milk is rejected in Iran. Also, the results of the K-W statistic indicate a structural change in 1995, indicating a structural failure in the preferences of Iranian consumers for milk. As a result, in future studies, it is suggested that special attention be paid to behavioral economics and consumer preferences for important products such as milk.

Study of resources changes in previous years could be useful in the planning and optimal using of resources to control inappropriate changes. Because land use changes occur on large-scale, remote sensing technique is a useful and valuable tool for monitoring the changes. The aim of this research is land  cover changes detection in a period of 32 years in Pishva town with using remote sensing technique .First TM, ETM and OLI images for the years 1986, 2002 and 2018 were collected respectively and after geometric and radiometric corrections, images were classified by using maximum likelihood classification methods. Kappa and overall indexes were used to calculate classification accuracy. Results showed in past 32 years, bare land and irrigated land have decreased while residential and greenhouse areas have increased. Classification accuracy showed that OLI, ETM and TM sensors have high accuracy respectively with kappa 0.96, 0.80 and 0.76 and also overall indexes of 97.56, 86.54 and 86 percent. Based on results, in the first period (1986-2002) 27.6%, in the second period (2002-2018) 29.60% and in the third period (1986-2018) 31.8% of area land cover have been changed. Results showed land cover changes in the area is related to climate changes like low precipitation, drought and social condition like population and food need increasing and economic condition like high production and efficiency.

Rice (Oryza sativa L.) is one of the three major food crops worldwide. Approximately 50% of the world’s population uses rice as a staple food. Silica and zinc among nutrients play a key role in improving plant nutrition and increasing rice growth, so that a lack of these elements reduces growth and consequently reduces yield. Also fortifying rice with silicon and zinc can correct deficiencies of these elements in humans who consume rice.

This experiment was conducted as factorial based on a randomized complete block design with three replications at the private farm located in Babol (North of Iran) during the years 2017-18 and 2018-19. Measured values of electrical conductivity, soil acidity, organic carbon, total nitrogen, available phosphorus, available potassium, zinc content and soil texture for the first and second years were 2.33 dS m -1 and 1.27 dS m -1 , 7.48 and 7.26, 3.27 % and 2.16 %, 0.32 % and 0.21 %, 11 mg kg-1 and 6 mg kg-1 , 320 mg kg-1 and 238 mg kg-1 , 0.96 mg kg-1 and 0.89 mg kg-1 , Clay and Clay, respectively. The treatment included three levels of foliar application (Potassium silicate, Silicon nanoxide, and Zinc nanoxide) as the first factor and five levels of developmental stages (T1: beginning of tillering + middle of tillering + late of tillering + end of panicle emergence, T2: middle of tillering + late of tillering + end of panicle emergence, T3: late of tillering + end of panicle emergence, T4: late of tillering and T5: end of panicle emergence) as the second factor.

The results showed that none of the studied traits were affected by the year. Maximum grain yield was obtained by foliar application silicon nanoxide (7733 kg ha-1 ) and zinc nanoxide (7498 kg ha-1 ), which was, respectively, due to increasing the total number of spikelets and the percentage of filled spikelets (1420.0 spikelets and 95.53%, respectively) and increasing the total number of tillers and 1000- grain weight (19.73 tillers and 26.80 g, respectively). The highest grain yield (7716, 7700 and 7492 kg.ha-1 ) and the percentage of filled spikelets (94.83, 94.72 and 93.89%) were obtained under T1, T2 and T3 treatments, respectively. By foliar application of silicon nanoxide and zinc nanoxide, the highest biological yield (19213 and 18986 kg ha-1 , respectively) and, the highest grain silica concentration (3.13%) and grain zinc concentration (15.97 mg kg-1 ) were recorded. The minimum 1000-grain weight (24.11 and 24.00 g), the maximum total number of spikelets per panicle (143.1 and 143.2 spikelets) and the highest concentration of grain silica (3.00 and 2.97%) were obtained under T1 and T2 treatments, respectively. However, the highest total number of tillers per hill and the highest number of grain were obtained under T1 and T2 treatments, respectively. The interaction between treatments showed that the maximum total number of spikelets per panicle was obtained by foliar application of potassium silicate under T1 treatment (151.5 spikelets) and foliar application of silicon nanoxide under T2 treatment (153.3 spikelets). Also, the highest concentrations of silica and zinc in grain were obtained by foliar application of silicon nanoxide under T1 treatment (3.97%) and zinc nanoxide under T2 treatment (21.67 mg kg-1 ), respectively.

According to the results of this study, we found that grain yield increases with the application of nanoparticles as well as foliar application during crop growth and development. In order to enrich rice grains, foliar application of nanoparticles in the middle of tillering, late of tillering and end of panicle emergence is also necessary

The aim of this study was to identify the effects of urban development on rangelands and forests of Sirvan city. In terms of nature, it has been a descriptive-analytical research by the use of Landsat 5TM satellite sensors of 1987, Landsat 7 ETM + sensors of 2000 and Landsat 8 of OLI sensors of 2016 in order to collect data. After performing geometric and atmospheric corrections on the maps, images were classified through maximum likelihood algorithm supervised method with and LCM method was used to analyze the changes. The attempt was made to study the trend of land use changes in Sirvan city to protect the forests and pastures of Sirvan city, so that it could be planned for better management. Findings showed that in the period 1987 to 2000, about 140 ha of pastures were built for human lands and in the period 2000 to 2016, about 395 ha of pastures and 20 ha of forests were built for human lands. In a period of 29 years, 6850 ha of pastures and 680 ha of forests were changed to agricultural lands and according to the results, urban development has turned the rangeland and forest lands of Sirvan city into residential lands.Urban Development.