precipitation

Environmental problems in the world are a manifestation of unsustainable and inconsistent development with the capacities of the earth. Climate change is among all the problems, due to the global impact on the scale of the earth and effects such as floods, storms, unusual rain showers, increasing intensity, duration and volume of droughts, heat waves, melting of polar ice, rising sea water levels and going under water, loss of coastal lands, increase in minimum and maximum temperature in most areas, increase in evaporation and transpiration and water requirement of crops and Baghi, more evaporation of surface water and reduction of available fresh water sources, reduction of precipitation, increase of erosion and dust storms have attracted the attention of countries more than before. Iran, as one of the countries influencing the increase of greenhouse gases, is trying to increase adaptation and reduce the risk of climate change risks in order to manage surface and underground water resources, agriculture and improve the level of food security, natural resources and biodiversity (biological resources) and health of the country. In this regard, it is necessary to establish the governance of climate change in the policies and executive measures of the country at different national, regional, provincial and local levels in such a way that adaptation to it is implemented as a part of the country's daily life and development environment and as a result of increasing the level of environmental resilience, social, economic and cultural, all classes will benefit from its results. Climate change is one of the important factors that will affect different parts of human life on the planet and will have harmful effects on environmental, economic, social and especially water resources. For a long time, the change in meteorological characteristics of different regions of the world has been proven for researchers. The reduction of precipitation, reduction of surface currents and changes in the production and performance of agricultural products can be felt in many regions of the world. Our country is also facing many issues in this regard. Climate change has a significant impact on water resources and environment, which in turn is reflected in agriculture, society and economy.The increase in the concentration of greenhouse gases in the last few decades and the resulting increased temperature have led to significant changes in meteorological elements. Global warming, climate change and changes in temperature and precipitation parameters have now become one of the most important environmental challenges in the world. The reason for this is that these changes will cause droughts or severe, short and long term floods in the future. Therefore, one of the ways to reduce the effects of climate change is to evaluate its effects on rainfall and temperature in each region.

In order to simulate the climatic data, at first, the observational data of Arak synoptic station including minimum temperature, maximum temperature, precipitation and daily sunshine hours in the statistical period of 1980-2005 were obtained from the country's meteorological organization. Also, CanESM2 global model data under RCP2.6, RCP4.5 and RCP8.5 scenarios along with observational data related to National Center for Environmental Variables Prediction (NCEP) were downloaded from this center's website. In order to scale the output data of CanESM2 and HadGEM2-ES models, LARS-WG model was used. LARS-WG model is also one of the statistical exponential microscale models. This model is one of the most famous meteorological data generation models, which is used to generate daily data of maximum and minimum temperature, precipitation and sunny hours in a station under current and future climate conditions (Alizadeh et al., 2013). In this research, the 6th version of this model was used to scale the output of the HadGEM2-ES model. In the LARS-WG model, after receiving the daily observation data (minimum temperature, maximum temperature, precipitation and sunny hours), the statistical characteristics of the data were extracted. Then, in order to ensure the ability of the model, a series of artificial data was produced in the base period (1980-2005) and compared with the observational data. In order to calibrate and ensure the accuracy of LARS-WG model performance, simulated variables and real data were evaluated. The results show that the LARS-WG model has a good accuracy (R2=0.99) in simulating the minimum and maximum temperature. Also, the accuracy of the model in simulating precipitation (R2=0.98) is acceptable.

Based on the results of the model under the RCP8.5 scenario, the LARS-WG model shows a decrease in rainfall in all three periods, which is consistent with the assumption that the continuation of global warming will lead to a decrease in rainfall. Based on the results, LARS-WG model has predicted minimum temperature increase in all three scenarios and all three periods. Regarding the annual maximum temperature, the results of the LARS-WG model have increased in all three scenarios and all three periods compared to the base period. The minimum temperature and the maximum temperature simulated by the LARS-WG model increase under all three scenarios to reach the maximum value in the RCP8.5 scenario, which indicates the effect of the intensity of carbon dioxide emission concentration in the atmosphere as well as other It is a greenhouse gas. Also, the results showed that the most changes in the maximum temperature related to the RCP 8.5 scenario (from 23.12 in the first period to 26.51 degrees Celsius in the third period), the most changes in the minimum temperature related to the RCP 8.5 scenario (from 8.71 in the first period to 60/11 in the third period) and the most precipitation changes are related to the RCP 8.5 scenario. The period studied in this research was 2021-2040 (first period), 2041-2060 (second period) and 2061-2080 (third period). The modeling results show a decrease in rainfall in all three periods, which is consistent with the assumption that the continuation of global warming will lead to a decrease in rainfall. The minimum and maximum temperature changes showed that in most cases, the minimum and maximum temperature will increase in the future. The maximum temperature increase was more than the minimum temperature, so that the highest temperature increase occurs in the month of February by 1.89 degrees Celsius compared to the base period. Examining the changes in the amount of rainfall also showed that the lowest amount of rainfall in the coming period will be observed in the month of June in the amount of 07.07 mm. A decrease in rainfall on the one hand and an increase in temperature on the other hand can indicate that the increase in evaporation and transpiration and the decrease in snow cover can move the water balance towards land and reduce water reserves.

In order to achieve the objectives of this study and according to the statistics of existing stations, for research about the phenomenon of climate change in the plains of Haraz watershed of Mazandaran province have been used LARS-WG5 model and three scenarios A1B, A2, B1 and each in three series 2011, 2065-2046 and 2099-2080. By determining the 30-year base year from the statistics of the nearest synoptic station to this study area, the average monthly precipitation and temperature were simulated.According to the results of this study, very irregularly increasing changes in rainfall in October, November and January and decreasing changes in August in the period of 2095-2080 are expected in the area. In the case of temperature changes in the watershed of Haraz plains area in the period 2095-2080 for scenarios A1B, A2 and B1, the trend of increasing the average monthly temperature shows even more than the two previously studied periods, so that the average temperature of July and August in the next period 2099-2080 by scenario A1B with 30/44 and 31/03, respectively, that it will reach 30 higher degrees Celsius and the average temperature in January and December will increase to 11.08 and 12.55 with an increase compared to the base period. The increase in temperature in the summer months, which coincides with the decrease in rainfall, has a significant role in the agriculture of this region, which is one of the important rice production areas of the country, and affects the downstream hydrological cycle of Haraz watershed. On the other hand, winter temperature changes can affect the time of snow melting in the basin, which has a significant effect on the peak flood discharge downstream of the watershed.

The purpose of the present study is to investigate the effects of climate variables on the width of the growth rings of Cupressus sempervirens Var. Horizontalis In the cities of Rudbar and Noshahr in Gilan and Mazandaran provinces. For this purpose, the number 13 discs were totally prepared from the breast height of the trees in two regions and after the preparation of samples including: cutting, sanding and specifying the borders of growth rings, the surfaces of the discs were photographed. Images were imported to Digimizer software in JPG format and the width of the growth rings was measured with 0.01 mm accuracy. Then the standardization and time matching steps were performed on the images. The chronological length of 38 years (1979-2017) gained and matching of the variance (GLK) of 77.26 and 70.10%, for Rudbar and Nowshahr measured, respectively. The average growth of 2.46 mm for Rudbar tree rings and 5.20 mm for Nowshahr tree rings were obtained. The results also showed that the growth of trees in Rudbar region had a positive and high correlation with precipitation factor (r = 0.94) and a negative and moderate correlation with temperature factor (r = -0.51). However, the effect of climatic factors on the growth rings of trees in Noshahr was not significant. According to the results of this study, the lack of dry season and mild condition of the plain in Noshahr area,

Winter precipitation in western Iran is the source of groundwater resources in the region. From this point of view, the study of Extreme winter precipitations in western Iran is very importance. in January, with the spread of western winds, all stations are under the influence of rainfall systems , thus In in this study, extreme precipitation of January have been analyzed in western . According to pervasiveness precipitation criterion in the region level, 10 items of the four-day precipitation periods of January with precipitation maximum from 1996 to 2017 by statistic processing. Finally, from these cases, the four-day period of 3 to 6 January 1996 with most intensity was selected for in this study. The results indicated that the maximum of precipitation has observed in the south, and inland aspects of the zagros. precipitation has been decreasing from south to north of the region. The influence of the Mediterranean system on the bed of a deep trough and its accompaniment with the special humidity stream from the side of warm seas of low Geographic latitudes has provided conditions for the maximum precipitation event in the region.

Changes and fluctuations of precipitation are one of the most important climate change outcomes in the world. The changes in surface water flow and hydrological cycle are directly affected. Therefore, recognition of fluctuations behavior and its governing patterns in a catchment area plays a very important role in optimal management of catchment areas. Therefore, in this research, we have tried to identify the trends of fluctuations patterns of rainfall and also the type of precipitation trend in the Golpayegan catchment area. For this purpose, daily rainfall data of precipitation stations near the Golpayegan saline wetland were used. For trend analysis, linear regression and Mann-Kendall method were used and for identify the rainfall prevailing cycles, Spectrum analysis technique was used. The results of trend analysis showed that in all studied stations, rainfall had a significant decrease. The highest trend is a significant decrease of 23 mm for the Golpayegan station. The results of spectral analysis also indicate that the short-term cycles of 2 to 5 years are in most of the studied stations. Most scientists have attributed this cycle as a result of El Niño - Southern Oscillation (ENSO) and Quasi-biennial oscillation (QBO).

The purpose of this study is to investigate interpolation methods for estimating and rehabilitating climate data. Due to the fact that two factors of rainfall and temperature are known as the most effective parameters in many applied decisions and in many studies of land physics, agriculture, hydrology, etc., climatic data are used. But climatic data are not always available at all intervals, or researchers need weather data to predict climatic conditions. In these cases, different interpolation methods are used. Therefore, in this research, existing methods for interpolation of climatic data in Ramsar, Babolsar and Bandar Anzali cities were evaluated. The results of the research indicate that the Neville and Spline interpolations provide a more accurate approximation for all studied cities. Other findings of the study are that temperature interpolation for the months of the summer season is less than the winter. There was also no significant difference between interpolations for different cities

Aim and Diphtheria toxin is an extracellular protein of Corynebacterium diphtheria that inhibits protein synthesis and kills susceptible cells. Ammonium sulfate is an inorganic salt that is used to purify and precipitate proteins, which, by increasing salt content, decreases the solubility of proteins, and proteins interconnect and precipitate through their hydrophobic parts. Diphtheria vaccine is prepared by purifying and treating toxoid diphtheria bacteria, which is one of the methods of treating, using ammonium sulfate as a dry salt or preparing an over-saturated solution.
Material and Diphtheria bacteria grown in optimal conditions and increased nutrient and toxin production by bacteria and inactivating the toxin into toxoid, in the manufacture of the vaccine is use. All media must be at least 24 hours at a temperature of 37-35°C will be incubated. In order to bacterial toxoid deposition of supersaturated solution 4.32 M ammonium sulfate with different percentages were used. The results of this procedure were investigated using SDS PAGE and Lf TEST ( Lateral Flow Test). Results revealed the use of 4.32 M supersaturated ammonium sulfate instead of the use of dry salt of ammonium sulfate, used in the traditional method (WHO TRS, No. 980), used previously in the vaccine industry, Eliminating the long-term dialysis phase On the other hand, the final product (toxoid) has been tediously reduced It also removes unwanted impurities from the finished product And has made the net product even more scalable. Since the purpose of vaccine production is industry to achieve maximum toxoid of the bacteria, so use the procedure in this research project (optimizing of DT toxin precipitation by 4.32 M super saturation of ammonium sulphate) , in addition to reducing the loss of the final product and remove the prolonged dialysis stage and so the economy will become more affordable.

Nowadays¡ human activities such as discovery¡ migration¡ trade and tourism mostly are influenced distributional pattern and range of some species In this research¡ patterns of current and future (2040) distribution of H. flaviviridis which as species with distribution by anthropogenic introduction¡ have been studied. In total¡ 19 bioclimatic variables have been extracted from Worldclim website and then seven non correlated bioclimatic variables and 40 point localities were performed using MaxEnt software. Results of species distribution modelling showed coastal southern of Iran having highly habitat suitability. Results of forecasting showed eastern Iran in Sistan and Blouchistan¡ central the Iranian plateau¡ Khuzestan province having habitat suitability in the lower suitability levels. However¡ the most important bioclimatic variables which contributing in modelling on distribution pattern of H. flaviviridis including precipitation seasonality and precipitation of the warmest quarter. Recognition invasive species is necessary in order to mange priorities¡ maintain biodiversity¡ prevent and control invasive species.

Aim and In the last years, a variety of biopolymers have been investigated as soft matrices to accommodate magnetic nanoparticles. Polymer encapsulation provides the surface functionalization and protection of the magnetic core from environmental perturbation. Furthermore, polymer coating could enhance the compatibility between nanoparticles and aqueous medium, prevent particles from oxidation, reduce toxicity, and extend storage life. In this study, new magnetic nanoparticles were synthesized by the co-precipitation in the presence of starch. The obtained nanoparticles were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). According to the analysis carried out, particles less than 40 nm were obtained and starch-coated magnetite nanoparticles were well synthesized. This work provides a simple and fast method for obtaining starch-coated nanoparticles.

Jarosite is one of the limiting factors for recovery of copper from copper sulfide minerals. This study aimed to evaluate the influence of concentration of ferrous sulfate, pH and temperature on the jarosite formation during the sulfide ore bioleaching of Sarcheshmeh copper mine. In this study, samples were collected from the depot crushing heap bioleaching site of Sarcheshmeh Copper Mine. The bioleaching experiments were performed in 500 ml flasks, containing 10% solids of sulfide ore  (w/v), pulp (200 ml), the 9K culture medium, bacteriainoculation (10% v/v of Acidithiobacillus ferrooxidans). The flask were shaked at 130 rpm throughout incubation. Our results showed that increase in pH and concentration of ferrous sulfate facilitate rate of ferric iron precipitation. Maximum precipitation rate of ferric was achieved in 50 g/l of sulfate concentration, temperature 32 ° C and pH 2/2. According to XRD and FTIR analysis of Bioleaching residue, the produced ferric precipitations are often potassium and ammonium jarosite. With regard to the optimal conditions in this study in terms of pH, temperature and concentration of ferrous sulfate it is possible to regulate Jarosite formation through bioleaching process and to increase the production of copper efficiency from copper sulfide ores.

One of the most striking phenomena in the Caspian Sea is the sea level rise. Sea level fluctuation is due to climatologically changes, regional precipitation, water evaporation, temperature, wind stresses, surges and geomorphology changes in the sea bed, alteration in atmospheric transport pattern as well as human activities such as construction of dams on the major rivers. More meteorological studies of Caspian Sea region as well as advanced watershed and ocean modeling must be used in order to predict the sea level fluctuation with acceptable results. In this research the variation of evaporation and precipitation in five coastal stations of south Caspian Sea from 1993 to 2008 has been studied and determines what are the effects of precipitation and evaporation in Caspian Sea fluctuation during this pried. The mean calculated evaporation in this period is about 922.9 mm. It is less than the mean calculated evaporation for long term period that is about 1007 millimeter/year. Mean calculated precipitation in this period is about 1292.6 mm. It is higher than mean calculated precipitation for long term period that is about 1221 millimeter/year. So in southern Caspian Sea, the increase of precipitation and the decrease of evaporation have an important role in sea level rise in recent years. The statistical index and correlation between atmospheric parameters are also determined and discussed in this research.