Failure of parts may happened under the influence of four parameters, design, materials, production process and improper use or combination of these. Therefore, the goal of studying the cause of parts failure is to specify any those parameters and avoid repeating them. Crank shaft is an important component of internal combustion engine that experiences a large number of load cycle during its service life. Crank shaft is subjected to several forces which vary in magnitude and direction. Most of crank shaft fails in cause of fatigue in fillet areas due to bending load. In this research, the failure causes of a train crank shaft were studied using chemical analysis, macroscopic and microscopic investigations by optical and scanning electron microscopes, measurement of journals surface roughness and radius of fillet and mechanical properties. It was found that the cause of failure is fatigue, but a lot of inclusions and probably high roughness and partial decarburizing due to machining have been decreased the fatigue strength.

Adsorption technology due to inexpensiveness, simplicity of operation, universal nature and effectiveness has been considered as one of the promising method of separation processes. Thereby in this study an adsorption process was applied by using activated carbon as adsorbent for separation of three pollutants of ethanol, acetaldehyde and acetic acid from aqueous solution. The solution contained 5 wt. % ethanol, 1. 5 wt. % acetic acid and 0. 2 wt. % acetaldehyde and in this work the effect of three parameters including retention time, solution temperature and adsorbent dosage were investigated. Moreover, the experiments were designed and optimized by RSM method and the results revealed that the optimal retention time, solution temperature and adsorbent dosage are 4 hr, 30° C and 2. 8 g adsorbate/cc solution, respectively. The maximum amount of adsorption for ethanol, acetic acid and acetaldehyde was determined to be 65, 85 and 85%, respectively and their adsorption capacity was calculated to be 144. 4, 64. 2 and 7. 6 mg adsorbate/ gr adsorbent.

In the present research, the equilibrium data of ternary systems, carbon dioxide- toluene- naphthalene is determined by using a high-pressure apparatus. Mentioned data is measured between 298.15 K and 308.15 K and pressure at 9.6 to 75.6 bar. In each experiment, equilibrium solubilities of naphthalene in toluene decrease by increasing the pressure due to adding the carbon dioxide as the anti-solvent. Also, the obtained experimental data have correlated by the Soave-Redlich-Kwong equation of states along with Van der Waals 1 and 2 mixing rules.The adjustable parameters of mentioned models are obtained using the experimental data and reported along with average absolute relative deviation of each model. The results show that SRK equation of state with vdW2 mixing rule (AARD=11.75 %) has less deviation than SRK-vdW1 (AARD=14.41 %) and optimum operational condition for production of fine particles (over than 90%) in the GAS process has been suggested.

Adsorption and desorption of substances in the surface of adsorbent materials are very important in various chemical industries. In this work، at first، desorption of carbon dioxide on activated carbon fixed bed were examined، then by using of a two dimensional geometry and finite elements method with COMSOL multiphysics software the desorption phenomena were simulated numerically. By using of the proposed numerical model the effects of some effective parameters were studied theoretically. Modeling of activated carbon fixed bed was performed for two fixed and mobile phases in the bed and in stationary and time dependent regimes. Based on the reported results in this work، the mass transfer coefficient and the outlet flux of carbon dioxide from the particles of bed are effective parameters on the desorption phenomenon.

The aim of this study was to recognize the transformation of soil organic matter fractions in burned and unburned pasture lands. The study area was a pasture land located in Alvand hillslope (toposequence), near the village of Haidara, Hamadan. The low-intensity wildfire occurred in the hillslope in autumn (October) 2015, in such a way that half the toposequence was burned up to the bottom symmetrically. Soil samples were gathered from three locations (up, mid, and down) of burned and unburned parts of toposequence 2 (December, 2015-autumn) and 9 months (June, 2016-spring) after wildfire occurrence. In each location, soil sampling was carried out in two parts; between the bushes and under their canopies and in two depths; 0-5 (upper) and 5-10 cm (lower) layers, respectively. Litter samples were also gathered in a 30*30 cm2 plot for each burnt and unburnt parts of toposequence. All sampling was carried out in three replications. The light fraction of organic matter (LF), cold and hot water extractable organic carbons (CWEOC and HWEOC), biomass carbon (BC), total organic carbon (TOC), and basal respiration (BR) were measured. The data analyzed in split-split plot design for each layer (upper and lower) and each season (autumn and spring) of sampling separately. In the mentioned statistical design, sampling location on toposequence (up, mid, and down) was regarded as the main plot, fire impacted area (burnt and unburnt) as a subplot, and sampling location related to bushes (between and under canopy) as sub-sub plot. Soil OC and BR were higher in the upper layer and under the bush's canopy rather than the lower layer and between bushes. In general wildfire increased TOC (42%), LF (41%), and BC (52%) in the sampled soils. In contrast, CWEOC, HWEOC, and BR in burnt soils were 61, 52, and 48% lower compared to those in unburnt soils, respectively. Although in autumn the litter content was lower on burnt soils compared to those in unburnt soils (50%), in spring it significantly increased on burnt soils. The increases in litter on burnt and unburnt soils were 4. 5 and 2 times, respectively. The study showed that wildfire and burning of plant cover by producing biochar on the pastures can improve carbon sequestration in soil.

Background and Objective: Rangelands are one of the natural ecosystems that have an important part of soil carbon reservoirs and also, as very diverse genetic reservoirs guarantee the dynamics of the ecosystem. Fire is a natural factor in rangelands burning most of the existing natural cover. Rangeland fires directly alter soil microbial activity by burning soil microorganisms and indirectly by reducing organic matter, altering soil organic matter quality and other soil properties. Investigating the positive and negative effects of fire on ecosystems, especially on soil properties, has led researchers to look for alternative methods, instead of direct methods, which are generally very costly and time-consuming. One of the new methods and technologies that are very useful in the field of natural resources is satellite remote sensing. The purpose of this study was to investigate the short-term effect of fire on organic carbon, acidity, and electrical conductivity of rangeland soils in the Gonbad region of Hamadan, and to investigate the capability of remotely sensed data in the indirect estimation of soil surface carbon in semi-arid rangelands after the fire. Materials and Methods: In this study, 20 soil samples were taken from each site from a depth of 0-10 cm (40 samples in total) and the coordinates of each sampling point were recorded with a GPS device. Sampling was performed 15 to 20 days after the fire in early October. After transferring to the laboratory, the samples were used to measure the amount of soil organic carbon. Then, the statistical relationship between non-burned areas and burned areas was examined and analyzed by an independent t-test. Indirect estimation of soil surface organic carbon at non-burned and burned sites was also investigated and their changes were evaluated using remote sensing satellite imagery. For this purpose, after performing the pre and post-processing on satellite data, the corresponding values of spectral reflectance of each pixel with sampling points at different wavelengths and spectral indices were extracted, and the correlation and regression equation of indices with the Carbon reservoirs were analyzed. Results and Discussion: The results of the Pearson correlation test showed that among all spectral indices, only the HI index was correlated with soil organic carbon in the short time and in the non-burned site. Besides, among all indices, BI, NDBI, NDVI, SAVI, VCI, and VHI indices were correlated with the EC value in the non-burned site. At the non-burned site, there was a significant correlation between most spectral indices and soil EC, which was eliminated after the fire at the burned site. Regarding the correlation between pH and spectral indices, it was observed that there is a correlation between some spectral indices and pH. As a matter of fact, it can be concluded that the fire has caused a large change in the rate of reflection and propagation of waves from the soil surface so that in the non-burned site, the indices were correlated with EC, but in the burned site, the correlation between indices and EC was completely eliminated, and instead, a correlation has been established between the indices and the pH. Furthermore, none of the spectral indices in April 2017 at the non-burned site had a significant positive or negative correlation with soil organic carbon, and the results showed that after six months of the fire, the soil carbon changes were not such that the spectral indices could be examined its process. Comparing the results of October 2016 with the results of April 2017 on the non-burned site, it was found that after six months, the NBR index has found a significant correlation with the EC rate, but the BI and VHI indices have lost their correlation. According to the NBR index and the SWIR2 band, it seems that after six months from the occurrence of the fire, changes have occurred in the control site, which has led to a correlation between this index and soil EC. Since the amount of reflected energy from the earth's surface depends on several factors such as soil moisture, changes in soil organic matter content, and surface cover, so the effect of these factors on the soil reflectance should be considered in the growing season. Failure to change these results after six months can prove that the positive and negative effects of the fire have not disappeared in a short period of six months and a longer time is needed for the situation to return to normal. Conclusion: According to the results, it was found that soil organic carbon reservoirs in burned rangelands in comparison with non-burned rangelands is not significantly different. Deformation and stabilization of soil organic matter due to fire have been studied by many researchers, but the transformation of soil organic matter by fire has often led to heterogeneous and different results. At a depth of 10-20 cm, the fire was found to have no effect on soil organic carbon content, but other researchers found that 6 months after the fire, the amount of carbon in the burned soils increased compared to the non-burned soils. It was also found that the percentage of soil organic carbon decreased significantly three months after the fire. Moreover, in another study on the effect of fire on soil organic carbon, it was found that in the area affected by the fire compared to the control area in one year and two years after the fire, the amount of soil organic carbon has decreased significantly. Since the effect of fire on the physical and chemical properties of soil is strongly influenced by fire intensity, soil moisture, climate, and vegetation, so all these factors have led to different results in investigating the effect of fire on soil organic carbon. Due to environmental conditions, climate, the slope of the area, soil texture and structure, and factors related to fire such as its intensity and duration, the amount of soil carbon has changed. For example, in the event of a medium-sized fire, the conditions for vegetation regrowth are faster, but in the event of a severe fire, the entire organic layer of the soil surface is generally removed and carbon is reduced over time. Also, in examining the correlation between spectral indices and soil organic carbon, it was found that only the HI index with soil organic carbon was significant at the non-burned site, but no correlation was observed at the burned site. This can be examined by examining the spectrum of visible blue and green wavelengths in the mathematical relationship of this index because only in this index the green and blue wavelength spectrum have been used. According to the results of other researchers, it seems that estimating soil organic carbon using remote sensing has certain complexities. Since soil organic carbon has the greatest impact on soil color, it is difficult to estimate it using remotely sensed data if its amount is low. The occurrence of fire in the region has a major impact on the spectral reflectance of surface soil so that after the fire in a short time the correlation of HI index with soil organic carbon is lost. According to the results of the present research, it seems that the main point about the impact of fire on soil organic carbon is the time and the opportunity for soil to change.

Fire is natural feature of most of ecosystems, including Mediterranean region and the site study in this research. In order to evaluate effect of fire intensity on dynamic of organic carbon, nitrogen and phosphorus of soil, 56 samples were selected from two depths (0-5 and 5-15 cm) in two areas of burned and unburned. Then, some unburned soil samples were burned in the laboratory by furnace at five temperature levels including of 95, 150, 220, 350 and 490oC for 30 minutes. The amount of organic carbon, total nitrogen and available phosphorus were measured by Walkley-Black method, Kjeltec method and Olsen method, respectively. Maximum organic carbon and total nitrogen were measured 4.44% and 0.89% in soil depth 0-5 cm burned at 150oC, respectively. Also, maximum available phosphorus was measured 14.99 (mg/kg) in soil depth 0-5 cm burned at 350oC. Overall it might be concluded that although increase in fire intensity, decreased total amount of organic carbon and total nitrogen, but increased amount of available phosphorus.

The main goal in this article is investigating and explaining Aristotle’ s two-part or tripartite analysis of attributive proposition and reviewing some of the opinions and views in this regard. In this article, we have tried to adduce Aristotle’ s works to show that firstly, although in Aristotle’ s view, the linguistic analysis of attributive proposition can be tow-part or tripartite, in logical analysis, the attributive proposition is always composed of two min parts, i. e. noun (subject) and verb (predicate), and the relation thereof is not considered an independent part due to being included in the meaning of the verb (predicate); and accordingly, attributing the tripartite analysis of attributive proposition to Aristotle as a logical analysis is wrong. Secondly, unlike some views and opinions, we do not find two different analysis of attributive proposition in Aristotle’ s logical works, and the basis for his discussions on ‘ analogy’ in his later works on logic (early analyses) is the very two-part analysis put forward by him in his early logical work (regarding clause). The main method in this study is referring to the texts of Aristotle’ s words and – where necessary – to Aristotle’ s interpreters and his followers or critics, scrutinizing those words, and analyzing, inferring and concluding based on them.

Fire is one of the main causes of carbon emission from forest stands. Therefore, the present study was conducted to investigate the amount of carbon emission caused by fire in the loblolly pine plantations in the Takhsam region that located in area of Lakan city of Guilan province. For this purpose, a burned region with 5 hectares’ area and a control region next to burned stand were selected and 5 circle sample plots with 4r (400 square meters) areas were accomplished in two stands by random-systematic method and trees diameter at breast height and total height in sample plots were taken. Then, by investigating the conducted studies Finally, 5 models selected to calculate the trees biomass in two stands. According to the results of this study, the average of trees biomass in the control stand was estimated between 93086. 98 (P model) to 10536. 9 kg/ha (model M) and the average of trees biomass in the burnt stand was estimated from 67829. 73 (P model) to 83509. 04 kg /ha (model M). The results of this study also showed that the carbon stock content in the control and fired stands was 48. 853 and 38. 357 tons per hectare respectively which showed significant difference in t-test. The amount of carbon emissions from the fire was 10495. 69 tons per hectare and the total carbon emission at the surface of the fire spot was about 52. 478 tons. Among the selected models, P model (BD = β 0 +β 1(DBHβ 2)) provided the least standard deviation in the calculations.

The objective of this study was to investigate the effect of wildfire in the rangelands of the Gonbad region of Hamedan on soil organic carbon storage in two control and fire areas after three years of fire, and the feasibility of using remote sensing in indirect estimation of soil carbon. Therefore, 20 soil surface (0-10cm depth) samples were collected from the burned area and 20 samples from the control area (40 samples in total) by the systematically random method after three years of fire time. Changes in organic carbon, total nitrogen, acidity, and salinity of surface soil were tested by independent t-test between control and fire areas. Then, to investigate the linear relationship between the storage of soil organic carbon with other parameters, the Pearson correlation was used in SPSS v. 26. The results of the independent t-test showed that there was no significant difference in EC, acidity, and soil organic carbon of the control and fire areas, but the amount of total soil nitrogen showed significantly different. The results showed a significant positive correlation was observed between soil organic carbon and total nitrogen at the level of one-hundredth of 0.830 (p< 0.01) in the fire area, and the BI index showed a significant negative correlation of 0.727 (p< 0.05). In the control area, a significant positive relationship was observed between organic carbon and total nitrogen at the rate of 0.627 (p <0.05). The results of processing Landsat 8 images (OLI-TIRS sensor) in the fire area showed that there was a statistically significant relationship between soil organic carbon and light and wetness index obtained from tasseled cap (-0.726 and 0.674, respectively) and PC1 component obtained from principal component analysis and -0.724 (p <.05). These results indicate that it is possible to use tasseled cap images to predict soil organic carbon in fire areas.