P. Mohseni; A. M. Borghaee; M. Khanali
Abstract
Introduction Today, grapes are cultivated in a vast zone worldwide. Grapes are among the major horticultural produced in Iran and the country is ranked 10th in the world for the grape production. Therefore, efficient use of energy from this crop is very important. Energy is one of the principal requirements ...
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Introduction Today, grapes are cultivated in a vast zone worldwide. Grapes are among the major horticultural produced in Iran and the country is ranked 10th in the world for the grape production. Therefore, efficient use of energy from this crop is very important. Energy is one of the principal requirements for the economic growth and development of agriculture. Scientific forecasts and analysis of energy consumption will be of great importance for planning the energy strategies and policies. The enhancement of the energy efficiency not only helps in improving competitiveness through cost reduction but also results in minimized greenhouse gas (GHG) emissions and environmental impacts. In other hand, energy analysis in the crop production systems enables to identify the effective farming system in different farm size with respect to energy parameters. Based on mentioned points, the objective of this study was to evaluate the energy flow of grape production in three sizes (small, medium and large) of land and then, the life cycle of the production in Hazavah Region of Arak city, Iran. Materials and Methods In this study, data were obtained from 58 growers using face-to-face questionnaires in Arak county of Iran. Orchards were selected using stratified random sampling. Investigation of the energy flow in a production system necessitate calculating input–output energies. In order to deal with this part, energy coefficients were taken into account to convert all agricultural inputs to their energy equivalent. In other words, each input was converted to its energy equivalent by multiplying the application rate of agricultural inputs used within the system by its energy coefficient. In order to evaluate how efficient, the system under study is, some well-known indicators have been introduced and widely applied when a production system is appraised. In this study, a life cycle approach was used for assessment of environment impacts of the grapes production. Life Cycle Assessment (LCA) refers to the process of compiling and evaluating the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle. Goal and scope definition, inventory analysis, life cycle impact assessment and life cycle interpretation are four mandatory steps, which should be followed in a full LCA study. The characterization factors used in this study were adapted from Simapro software which is linked to EcoInvent database. Results and Discussion On average, the values of consumed and produced energies were 1854 MJ ton−1 and 11800 MJ ton−1, respectively. Among all input energies, chemical fertilizers held the first rank with an amount of about 704 MJ ton−1. It accounted for 38% of the total energy used in the production season. Energy use efficiency, which is a ratio between output and input energy, was calculated as 5.75. Also, the energy productivity was estimated as 0.48, meaning that 0.48 kg grapes is produced when one MJ energy is consumed. The total Global Warming (GW) was calculated as 508.63 kg CO2 eq. ton−1. The farm size had an influential effect on the GW and other impact categories. An increase in the farm size led to reduction in the environment impacts. It means that the value of GW for large farms fell at 498.68 kg CO2 eq. ton−1 and the value of GW for small farms fell at 698.69 kg CO2 eq. ton−1. The upshot was that GW and other impact categories for large farms were significantly less than its counterpart in small farms due to the high value of grapes produced in large farm groups. Impacts of manure played a more important role on GW. Also, direct emissions of chemical fertilizers made high contribution to acidification and eutrophication. Management of using chemical fertilizers can be an appropriate way to reduce the acidification, eutrophication and other environmental impacts on the grape production. Conclusion Chemical fertilizers (38%), demonstrated their pivotal roles in total energy consumption. The direct emissions in the grape production resulted from high application of chemical fertilizers contributed considerably to some environmental impacts. It suggested establishing a sustainable and environmental friendly grape production system in the region with application of efficient fertilizers by integrated nutrient management.
A. Omidi; R. Alimardani; M. Khanali
Abstract
Introduction Geographical location and climatic conditions are the important factors affecting the wind energy potential of each region. Iran is a vast country with different climates and the exploitation of its wind energy needs to study and research on the meteorological data. In the study area during ...
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Introduction Geographical location and climatic conditions are the important factors affecting the wind energy potential of each region. Iran is a vast country with different climates and the exploitation of its wind energy needs to study and research on the meteorological data. In the study area during the warm season and the hottest hours of the day, coinciding with peak electricity consumption in the region and the country, wind blowing continuously carried out. The surpassed consumption over production of electricity in summer and vice versa in winter is considered as one of the country's problems. The aim of this study was to investigate the parameters of the wind energy and the feasibility of wind potential (in study area) in the warm season in particular and other seasons to supply the needed electrical power of area, avoid of unwanted blackouts, development of wind energy as an important renewable energy, attraction of investors, and policymakers to build wind farms in the study area. Materials and Methods This study was conducted in the Dehloran city, located in the southern part of Ilam province. The region has a temperate winter and very hot and dry summer. The important criteria for construction of wind power plants and using of its energy are wind power density and the annual wind speed average. For this reason and analysis, and statistical analyzes, wind data includes three-hour direction and speed were obtained from the meteorological organization and during 2004 to 2013. The average of annual, monthly and daily wind speed and their standard deviation were calculated. Based on the commercial turbines in the country, and the rotor blades are at altitudes up to about 80 meters, the wind speed at altitudes of 40, 60 and 80 meters was calculated. To evaluate the potential of wind speed the Rayleigh and Weibull distribution functions were used and their parameters were calculated. The wind energy potential using the available data and the Weibull and Rayleigh functions were calculated. Results and Discussion Based on the results of the ten-year data, average of wind speed had relatively slight variation, with the highest and the lowest value of 3.6 and 3.25 m s-1 in 2007 and 2010, respectively. The annual average was about 6 m s-1 in height of 50 meters that seems appropriate. The highest and the lowest monthly average values were 4.62 m s-1 and 2.24 m s-1 in June 2005 and November 2006, respectively. Generally, the warm months had significantly higher wind speed than that of cold months. The Weibull distribution function parameters, k and c were calculated. Minimum and maximum amount of k were 1 and 1.828, in December 2006 and May 2011, respectively. The minimum and maximum amount of c was 2.37 and 5.69 in November 2004 and June 2013, respectively. The highest value of wind power density was 312 w m-2 in June. The lowest power density was observed in November. Therefore, we can say that the wind energy potential of the region has coincident with peak electricity consumption in the warm months. The most frequent and the least frequent wind direction were the southeast and northeast, respectively. Conclusion Daily evaluation of wind speed during different months, seasons and years showed a significant change during the day that represented the high value of the wind speed in noon and afternoon. The highest value of monthly wind energy density was for the warm season. The lowest and highest power density was in November and June, respectively. Therefore, we can say that the peak of wind energy potential of the region has a coincident with the country's peak power consumption in warm months. With considering that the study area has a warm climate and high consumption of energy in the hot days of a year and the probability of unwanted blackout of electricity in warm months, and the long hours of the wind blowing in the mentioned times, construction of wind farm in these areas can be reasonable.
M. Mohammad Shafie; A. Rajabipour; H. Mobli; M. Khanali
Abstract
Introduction: The pomegranate journey from orchard to supermarket is very complex and pomegranates are subjected to the variety of static and dynamic loads that could result in this damage and bruise occurring. Bruise area and bruise volume are the most important parameters to evaluate fruit damage occurred ...
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Introduction: The pomegranate journey from orchard to supermarket is very complex and pomegranates are subjected to the variety of static and dynamic loads that could result in this damage and bruise occurring. Bruise area and bruise volume are the most important parameters to evaluate fruit damage occurred in harvest and postharvest stages. The bruising is defined as damage to fruit flesh usually with no abrasion of the peel. The two different types of dynamic loading which can physically cause fruit bruising are impact and vibration. The impact and vibration loadings may occur during picking or sorting as the pomegranates are dropped into storage bins and during transportation. The focus of this work was on the impact loading as this appeared to be the most prevalent. In view of the limitations of conventional testing methods (ASTM D3332 Standard Test Methods for Mechanical Shock Fragility of Products), the method and procedure for determining dropping bruise boundary of fruit were also established by adapting free-fall dropping tests.
Materials and Methods: After the ‘Malas-e-Saveh’ pomegranates had been selected, they were numbered, and the weight and dimension of each sample were measured and recorded. Firmness in cheek region of each fruit was also measured. Fruit firmness was determined by measuring the maximum force during perforating the sample to a depth of 10 mm at a velocity of 100 mm min-1 with an 8 mm diameter cylindrical penetrometer mounted onto a STM-5 Universal Testing Machine (SANTAM, Design CO. LTD., England). Free-fall dropping tests with a series of drop heights (6, 7, 10, 15, 30 and 60 cm) were conducted on fresh ‘Malas-e-Saveh’ pomegranates. Three samples were used for each dropping height, and each sample was subjected to impact on two different positions. Before the test was started, it was necessary to control the sample's drop position. The cheek of sample was placed on the fruit holder. An aluminum plate mounted on upper part of the piezoelectric force sensor was the dropping impact surface of the device. After dropping impact, the sample was caught by hand to prevent a second impact due to sample rebound. After impact, the samples were stored at room temperature for 48h, during which time bruise tissues and arils turned brown. The bruise area and bruise volume of each sample were calculated according to equations (1 and 2).
Results and Discussion: Dropping impact acceleration versus time curves for the typical samples at ten drop heights are shown in figure 5. Drop height notably affected the impact acceleration. The peak force increased while contact times decreased with increasing drop height, which resulted in an increase of peak acceleration. Figure 6 shows the dropping impact velocity change during contact by theoretical calculation. The results showed that the velocities at the beginning of contact and the rebound velocities of the samples increased with increasing the drop height. Critical drop height of pomegranate in certain bruise area was determined and linear relationship between drop height and bruise volume for ‘Malas-e-Saveh’ pomegranates were obtained. It is clear that there were obvious differences between dropping bruise boundaries of pomegranates and the conventional damage boundary of products (as shown in figure 9). For the conventional damage boundary, the vertical line, critical velocity (Vc), represents the velocity change below which no damage occurs, regardless of the peak pulse acceleration. The horizontal line, critical acceleration (AC), represents the acceleration at which the product will be damaged if velocity exceeds VC. At the same time, for a conventional product, there is only one damage boundary at one shock condition. However, for fruit, a change in drop height (velocity) will lead to a change in bruise ratio. A series of bruise boundaries can be determined for different bruise ratios. Moreover, even if the velocity approaches zero, the fruit can still be bruised if its acceleration exceeds a certain value. These relationships provide an effective basis to predict and control drop bruising, which may be achieved through the design of reasonable cushioning packaging for fruit.
Conclusions: This research applied the concept of dropping bruise for pomegranate fruits. Because of the limitations in using conventional testing methods to test product of a viscoelastic nature, such as fruit, free fall dropping tests were adapted to determine dropping bruise fragility and bruise boundary for ‘Malas-e-Saveh’ pomegranates at different drop heights. For viscoelastic products such as fruit, even if the dropping impact velocity approached zero, the fruit could be bruised as long as the impact acceleration exceeded a certain value (critical acceleration). A series of bruise boundaries can be established for different levels of bruise ratios, i.e., a contour of constant bruise ratio can be drawn on the velocity acceleration plane.
