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Showing 85 results for Lut

Mohammad Shahedi, Payman Goli Khorasgani, Zohreh Hamidi Isfahani,
Volume 3, Issue 2 (7-1999)
Abstract

Stickiness and pastiness after cooking is one of the basic problems of macaroni production technology. Investigation of the factors affecting stickiness and pastiness of Iranian Macaroni is essential. The purpose of this research was to study the effects of percentage of gluten in the flour as well as extruder and drying temperatures on the macaroni quality. The factors studied are as follows:

1- Percentages of flour gluten at levels of 8.5, 10.5, 12.5 and 14.5 prepared by adding gluten to the macaroni flour purchased from the market.

2- Temperature of the dough discharged from the extruder (three levels: 48, 58 and 68 °C) obtained through changing the temperature of the water used in making the dough, circulation and noncirculation water in extruder jacket, and changing the rotational speed of extruder screw and increasing dough retention time.

3- Drying temperature (two levels: 50 and 62 °C) obtained through changing the number of burners in the heating system and using electrical heaters in the drying cabinet.

 The results of the e:xperiments and their evaluation are as follows: using flour with a gluten percentage of 12.5 or 14.5 (12.5% gluten is preferred for economic reasons) with an extruder temperature of 48 °C and a drying temperature of 62 °C will improve the macaroni quality. This treatment resulted in the production of macaroni with less stickiness, pastiness and cooking loss.


H.r. Rahmani, M. Kalbasi, S. Hajrasuliha,
Volume 4, Issue 4 (1-2001)
Abstract

Soil as the third major component of our environment is exposed to different kinds of pollution. Lead has been recognized as a factor in environmental pollution. Pollution of soil and plants along the highways and roads by Pb from automobile exhaust gases has extensively been reported as the most important pollutant source in the environment. This research was carried out to determine the degree of soil pollution along the following highways: Rasht-Anzaly (Anzaly area), Kelachay-Ramsar (Ramsar area), Tehran-Karaj (Karaj area) and Isfahan-Tehran (Delijan area). In each location a transect of 100 meters long, perpendicular to the highway axis, was selected for sampling. Soil samples at different depths were taken from different distances from the highway and analysed for some physical and chemical characteristics and total Ph content by 5M HNO3 extraction.

 Results indicated that the total Pb content of soil decreased exponentially with distance from the roadside. Total Pb content of soil decreased sharply with depth in all highways except in one area indicating that Pb was retained in the surface soil and that its movement down to the deep soil was slow. Total Pb content of soils was highly and directly related to the traffic volume.


M. Shivazad, A. Seidavy,
Volume 5, Issue 1 (4-2001)
Abstract

An experiment was conducted in order to study the possibility of compensatory growth by changing dietary nutrients concentration in the female Arian broiler chicks using a completely randomized design by means of standard and diluted diets. By standard diet is meant diet recommended by Arian’s guide catalogue and by diluted diet is meant the diet used in Iran broiler farms. However, both diets contain the same nutrient/energy ratios. Chicks in the seven treatments received in their starter, grower and finisher stages standard and standard and standard, standard and diluted and diluted, diluted and standard and diluted, diluted and diluted and standard, diluted and standard and standard, diluted and diluted and diluted, standard and standard and diluted respectively. Furthermore each treatment contained three replicants and each replicant contained 30 chicks. This experiment was conducted in autumn using 630 female Arian broiler chicks for eight weeks.

 It was concluded that weight gain of chicks receiving standard diets during all stages of their growing period was the same as the chicks receiving diluted diet during their starter period and standard diets during grower and finisher periods. Feed consumption and feed conversion ratio of these treatments were statistically lower than other treatment groups. Furthermore, production index and percentage of mortality was better than other treatment groups. Likewise, viscera% and abdominal fat% remained significantly constant in all treatment groups. But the cost of feed per unit of live body weight was lower in the treatment receiving diluted diets in all three stages of their growing period.


R. Amiri, A. Rezai,
Volume 5, Issue 2 (7-2001)
Abstract

In order to evaluate the relationship between SDS-sedimentation value and breadmaking quality of wheat (Triticum aestivum L.), glutenin subunits of different genotypes (foreign and Iranian cultivars) were analyzed by reverse-phase high performance liquid chromatography (RP-HPLC). SDS-sedimentation value was used as an indirect criterion for breadmaking quality.

 Correlation coefficients revealed a closer relationship between low molecular weight (LMW) glutenin subunits and variation in SDS-sedimentation value. Principal component analysis confirmed the presence of association between some of the glutenin subunits and SDS-sedimentation value. Based on the stepwise regression analysis, two LMW and four high molecular weight (HMW) peaks (subunits) were selected which accounted for 70.2 and 18.7% of variability in SDS sedimentation values, respectively. On the basis of the results of the stepwise regression analysis, a discriminant function was developed. The great efficiency of discriminant function in correct classification of completely different genotypes (Iranian landraces and cultivars) showed that the observed relationship between glutenin subunits and SDS-sedimentation value has a genetic basis and the effects of LMW and HMW glutenin subunits on SDS-sedimentation value are additive. Therefore, it seems that this method based on more protein components (rather than only on HMW glutenin subunits) can be used to predict breadmaking quality of wheat against many genetic backgrounds.


M. Golabadi, A. Arzani,
Volume 6, Issue 3 (10-2002)
Abstract

To study grain quality traits and their relationships with high molecular weight (HMW) and low moleculor weight (LMW) glutenin subunits, 104 durum wheat genotypes were used. Six grain quality characteristics comprising wet and dry gluten content, test weight, grain hardiness, protein content and SDS sedimentation volume were studied. HMW and LMW glutenin subunits were evaluated using SDS-polyacrylamid gel electrophoresis (SDS-PAGE) in 33 genotypes. Statistical analysis including correlation coefficients, factor analysis, cluster analysis of genotypes based on qualitative traits, analysis of variance in qualitative traits based on HMW, LMW, and combination of subunits as well as all of subunits, and canonical correlation analysis between glutenin subunits and qualitative traits were used. Factor analysis of the genotypes detected 2 factors, which explained 65 percent of the total variation among the data. These were named quantitative protein and qualitative protein. Based on cluster analysis, the genotypes were classified into four clusters. The genotypes in groups 2 and 4 were beneficial in terms of protein quantity and quality. In evaluating glutenin subunits, 7 HMW subunits and 2 LMW subunits were detected. Subunit null of Glu-Al was observed. Subunits 7+8, 6+8, 13+16 and 20 at Glu-Bl were observed however, neither of them had significant differences in qualitative traits, but 6+8 and 7+8 had a higher SDS sedimentation rate than 20. LMW-1 and LMW-2 had significant differences in protein content and SDS sedimentation LMW-1 had higher protein content whereas LMW-2 had higher SDS sedimentation. Combibation of subunit LMW-1 / HMW 7+8 had the highest protein content and LMW-2/HMW 7+8 had the highest SDS sedimentation. Results of canonical correlation showed that presence of LMW-2 and HMW 7+8, and absence of LMW-1 and HMW 20 in durum wheats caused an increase in SDS sedimentation and a reduction in protein and gluten content.
M. Shabanpour-Shahrestani, M. Afyuni, S. F. Mousavi,
Volume 6, Issue 4 (1-2003)
Abstract

The objective of this research was to evaluate bromide leaching in a field under corn, wheat and alfalfa. Potassium bromide (300 kg/ha) was uniformly applied and 15 mm of water was sprinkled over the plots in the first and second years. Plots were leached 8 times during the first year and 9 times in the second year (each time with 100 mm of water). Soil samples were collected at 0-30, 30-60, 60-90 and 90-120 cm depths two days after each leaching practice. Bromide concentration in soil samples was measured using an ion selective electrode. Moisture content in each plot was measured using a neutron meter to a depth of 120 cm and after calculation of evaporation from soil surface, the net water applied was determined. CXTFIT software and Regional Stochastic Model (RSM) were used to simulate leaching under field conditions. The results showed that flow velocity and dispersivity of treatmens were not significantly different from the control in the first year, indicating that treatments had no effect on preferential flow. Control treatments were not significantly different in the first and second years. In the second year, flow velocity in wheat, corn and alfalfa treatments were 1.54, 1.86 and 2.21 times higher than flow velocity in the control, respectively. Dispersivity in alfalfa and corn treatments were 4.30 and 5.30 times higher as compared to the control. The increase in flow velocity and dispersivity is caused by an increase of preferential flow in the second year. The root channels remaining in soil at the end of the first year may also have increased preferential flow. After adding 25 cm of water, 30% of bromide leached from the top 50 cm soil in all plots in the first year and control plots in the second year but the values in the second year were 47, 67 and 70% of bromide leaching from the top 50 cm soil in wheat, corn and alfalfa plots, respectively.
K. Yussefi Kelaricolaii, A. Kamyab, M. Rezaei,
Volume 6, Issue 4 (1-2003)
Abstract

In a completely randomized design (CRD) experiment with 6 treatments and 4 replicates per treatment, the effect of energy and protein dilution during 6-12 days of age was tested in broilers. Rice hull was used for dilution of energy and protein at levels of 0.05 (control), 10, 15, 20, 25 and 30 percent. The metabolizable energy and crude protein content of the experimental diets were 3089, 2780, 2626, 2472, 2317 and 2163 KCal/kg and 21.45, 19.29, 18.23, 17.16, 16.10 and 15.02 percent, respectively. The results indicated that diet dilution at early age (6-12 days) increased feed consumption but energy and protein intake and weight gain were reduced. No significant differences in body weight were observed due to compensatory growth among treatments. After feed restriction, feed intake was lower for the birds receiving diluted diets as compared to control. Meanwhile feed efficiency somewhat improved among the birds fed with diluted diets, but the differences were not significant. Diet dilution had no significant effect on carcass and abdominal fat percentage at the slaughter age (45 days). Diet dilution with rice hull at 20 and 25 percent decreased feed consumption and improved feed efficiency and, therefore, its use can reduce feed cost.
M. Chorom, C. Jafari,
Volume 7, Issue 2 (7-2003)
Abstract

Environmental pollution is one of the major problems for humans and animals. Radioactive wastes and heavy metals are important sources of pollution. Recent studies suggest that soil and geomedia have a high potential for the disposal of radioactive wastes and heavy metals. The clay minerals in geomedia can act as a barrier against radioactive wastes and heavy metals. However, enough information and experimental evidence about the mechanisms involved in the fixation of metals by clays are not available. This study aimed to show the effect of clay type on the fixation of cobalt and cadmium as affected by thermal energy. Increasing the temperature from 25 to 400°C decreased the CEC of clays in Ahwaz and Darab soils saturated with cobalt from 35.6 and 50.1 cmolc+/kg to 28.8 and 4.5, respectively. In cadmium clays, however, reductions in CEC were minimal (from 34.3 and 51.2 at 25°C to 32.5 and 47.7 cmolc+/kg at 400°C, respectively) compared to cobalt saturated clays. Consequently, the bonding characteristics change according to the size of the cations upon thermal treatment. The small cation, cobalt with an ionic radius of 0.68 Å, apparently migrates to the octahedral vacant sites and forms covalent bonds after heating at 400°C to become non-exchangable (fixed). The larger cation, Cd with an ionic radius of 0.97Å, apparently does not migrate into lattice sites on thermal treatment and remains exchangeable.
M. Jalali Javaran, H. Hashemzadeh, A. Mousavi,
Volume 8, Issue 2 (7-2004)
Abstract

Analysis of transgenic plants is very important in gene transfer programs. In this research, the second generation (T1) of transgenic brassica napus which was transformed by antisense of Glutamine synthetase (GS) gene was studied from the view of total soluble protein content of leaf, total chlorophyll and protein patterns (SDS-PAGE) using seeds of Brassica napus .Protein concentration was determined by a calorimetric method described by Bradford method. Chlorophyll (a, b) and carotenoid contents were determined by spectrophotometry. The total soluble protein content of Brassica napus leaves increased from YG stage, reached a maximum level during MG2 and, after this, decreased with the progress of SS stage. Comparison of the total soluble protein between different treatments showed the highest level in the A2 plant and the least in the A6 plant. Comparisons with chlorophyll a and b were not significant between different treatments, but different stages showed significant differences with maximum and minimum levels obtained in the MG1 and SS, respectively. Protein patterns were also studied using SDS-PAGE method. No new band was recognized in the MG1 stage, but the density of some protein patterns was shown in YG and MG2 stages. In YG stage, differences were seen among the A5, A3, A4 and A6 with W.T on 41 KDa weighty position and also between the A1 and A2 with W.T treatment on 23/6 KDa. Considering the molecular weight GS1 subunit of glutamine synthetase (41 KDa) and the similar conditions in growth, protein extraction and macro molecular analysis in transgenic and control plants, we can tell that the difference shown in transgenic plants are probably due to the effect of the antisense of glutamine synthesis gene in this plant.
A. Jafari Malekabadi, M. Afyuni, S. F. Mousavi, A. Khosravi,
Volume 8, Issue 3 (10-2004)
Abstract

In recent decades, the use of nitrogen fertilizers has increased irrespective of their effects on soil properties, agricultural products and, particularly, on environmental pollution. Nitrate easily leaches from soils into groundwater. The objective of this study was to determine temporal and spatial nitrate concentrations in groundwater in agricultural, industrial and urban regions in some parts of Isfahan Province. Water samples were collected monthly from 75 agricultural, industrial, and urban wells of Isfahan, Najaf-abad, Shahreza, Natanz and Kashan during January-May 2001. The results indicated that NO3-N concentrations in most of the regions studied were higher than the standard level (10 mg/l) and nitrate pollution must be reckoned among the most serious problems of sustainable agriculture and exploitation of groundwater resources. Average NO3-N concentration in different wells ranged from 1.03 to 50.78 mg/l (4.64 to 228.5 mg/l as nitrate). The average NO3-N concentration in groundwater of Najaf-abad, Shahreza, Isfahan and Natanz-Kashan was 17.56, 14.6, 16.04, and 8.24 mg/l and 95.5, 100, 84 and 33.3 % of total wells in these regions had nitrate concentrations above the standard level, respectively. Maximum NO3-N concentration was detected in the agricultural region south of Najaf-abad (64.6 mg/l). Nitrate pollution in most of the sampling areas was mainly linked to agricultural activities. The average NO3-N concentration in groundwater of all agricultural, industrial, and urban regions, except for urban regions of Natanz and Kashan, were above the standard level. Generally, nitrate concentration level in groundwater increased with time and was maximum in March and April.
Sh. Ayoubi, M. H. Alizadeh,
Volume 10, Issue 3 (10-2006)
Abstract

Overgrazing is the most important agent which causes accelerated soil erosion and land degradation in arid and semi-arid zones of Iran. Appropriate planning and land use in these areas based on land suitability evaluation provide a suitable base for conserving the land and controling desertification. Land evaluation identifies possible alternatives in land use which will more effectively meet national or local needs and assists in assessing the consequences of these alternatives. Extensive grazing refers to the land utilization type in which animals feed in natural pastures. This study was performed to evaluate physical potential of the given watershed for grazing by sheep and goats, and assess the limiting factors for the land utilization type in Mehr watershed, Sabzevar, Khorasan province. Land qualities which were evaluated include accessibility to animals, soil erodibility, moisture availability, rooting conditions, salinity and alkalinity, and drinking water availability for animals. Above mentioned land qualities were assessed by appropriate land characteristics. The requirement of grazing land utilization type was defined in terms of rated land characteristics. Matching of requirements of LUT with the land qualities of each pixel of DEM (prepared in 200×200m by GIS software) resulted in a rating for every land characteristics. Some characteristics such as slope, aspect, and distance to drinking water for animals were calculated directly by GIS. Land index for every pixel was calculated by square root method. Finally, qualitative and physical land suitability classes were determined based on land indices and classified to polygons which would be suitable in grazing management. The results were interpreted under two different scenarios. In the first scenario, drinking water for animals was supplied by permanent sources and in the second one, the supplying of water was developed to temporary rivers besides the permanent sources. With the analysis of spatial modeling it was possible to assess the land suitability with higher accuracy. Overall results showed that the given area was not highly suitable for grazing at all. The most limiting factors included moisture availability for plant growth, slope, rock fragment and outcrops and distance to drinking water. Also during the late winter, spring and early summer, when the seasonal rivers were supplying the drinking water, the limitation of given area was decreased.
F. Abbasi, F. Tajik,
Volume 11, Issue 1 (4-2007)
Abstract

Estimation of unsaturated soil hydraulic and solute transport properties by Inverse modeling has thus far been limited mostly to analyses of one-dimensional experiments in the laboratory, often assuming steady-state conditions. This is partly because of the high cost and difficulties in accurately measuring and collecting adequate field-scale data sets, and partly because of difficulties in describing spatial and temporal variability in the soil hydraulic properties. In this study we estimated soil hydraulic and solute transport parameters from several two-dimensional furrow irrigation experiments under transient conditions. Three blocked-end furrow irrigation experiments were carried out, each of the same duration but with different amounts of infiltrating water and solutes resulting from water depths of 6, 10, and 14 cm in the furrows. Two more experiments were carried out with the same amounts of applied water and solute, and hence for different durations, on furrows with water depths of 6 and 10 cm. The saturated hydraulic conductivity (Ks) and solute transport parameters in the physical equilibrium convection-dispersion (CDE) and physical nonequilibrium mobile/ immobile (MIM) transport models were inversely estimated using the Levenberg-Marquardt optimization algorithm in combination with the HYDRUS-2D numerical code. Estimated Ks-values ranged from 0.0389 to 0.0996 cm min-1, with a coefficient of variation of 48%. Estimated immobile water contents (θim) were more or less constant at a relatively low average value of 0.025 cm3 cm-3, whereas the first-order exchange coefficient (ω) varied between 0.10 and 19.52 min-1. The longitudinal dispersivity (DL) ranged from 2.6 to 32.8 cm, and the transverse dispersivity (DT) from 0.03 to 2.20 cm. DL showed some dependency on water level and irrigation/solute application time in the furrows, but no obvious effect was found on Ks and other transport parameters. Agreement between measured and predicted infiltration rates was satisfactory, whereas soil water contents were somewhat overestimated and solute concentrations underestimated. Differences between predicted solute distributions obtained with the CDE and MIM transport models were relatively small. This finding and the value of optimized parameters indicate that observed data were sufficiently well described using the simpler CDE model, and that immobile water did not play a major role in the transport process.
H. Yosef-Zadeh, K. Spahbodi, M. Tabari, Gh. Jalali,
Volume 11, Issue 40 (7-2007)
Abstract

In this investigation, the effect of seed source on the germination and survival of Acer velutinum Boiss. was assessed. Seeds were collected from 11 seed sources ( located at 20 to 2200 meter a.s.l in Mazandaran forests) and planted in a mountain nursery (Orimelk located at 1550 meter a.s.l) as completely randomized block design with three replications. The results show that the effect of seed source on germination and survival was statistically significant (p<0.01). Germination and survival rates were lower for the Pasands, Ashak and Deis sources, and the maximum seed germination was related to Lamzer site. Effect of seed sources on survival of seedling was significant too. The maximum and minimum survival was related to Lajim and Ashak, respectively. Regarding plan table seedling, the effect of seed source was significant. The maximum efficiency of seedlings has been found in Lajim, Lamzer, Parke Noor and Sangdeh sites, while the minimum range of efficiency was related to Ashak and Pasand2.
N. Mirghaffari, H. Shariatmadari,
Volume 11, Issue 41 (10-2007)
Abstract

Concentration of soluble fluoride in groundwater, soil, and some crops in Isfahan region was determined by Ion Selective Electrode (ISE) method. The mean fluoride concentration of water samples in the study area was 0.3 and 0.05 mg L-1 in the spring and summer, respectively. These values are in an acceptable limit for irrigation, whereas for drinking water, they are in deficiency range. The average and maximum concentrations of soluble fluoride in soil samples were 1.0 and 3.2 mg kg-1, respectively. In general, the spatial distribution of fluoride in soils showed that fluoride content around major industrial centers such as Isfahan Steel Factory, Mobarakeh Steel Co., and Isfahan oil refinery was higher than other sites. The minimum and maximum fluoride contents of crops were observed in alfalfa as 0.2 and in corn as 4.2 mg kg-1, respectively. Tomato had the highest mean concentration of fluoride as 3.6 mg kg-1. The fluoride concentration in plants positively correlated with the fluoride concentration in irrigation water and soil (P < 0.01) and negatively correlated with cation exchange capacity of soil (P < 0.05).
H. Khodaverdiloo, M. Homaee,
Volume 11, Issue 42 (1-2008)
Abstract

  Phytoremediation is a new technology that employs plants to remediate contaminated soils. This method compared to those that involve the use of large scale energy consuming equipments is an inexpensive method. Phytoremediation models are useful tools to further understanding the governing processes and also to manage the contaminated soils. A thorough literature review indicates that very few models have been developed for phytoremediation due to the complexity of the phenomena. The objective of this study was to develop a simple model for phytoremediation of lead and cadmium. A new formulation of phytoremediation was established based on soil and plant responses to heavy metal pollution. A large quantity of a sandy loam soil was thoroughly mixed to ensure homogeneous different concentration levels by lead and cadmium. These contaminated soils were transferred to some plastic pots. Land Cress (Barbarea verna) and Spinach (Spinacia oleracea L.) seeds were germinated in pots containing 8 kg of contaminated soil. Plants were harvested at five time intervals. The concentrations of Pb and Cd in the plant and soil samples were digested by wet oxidation and 4 M Nitric acid digestion methods, respectively, and were determined by flame and graphite furnace atomic absorption spectrometry methods. Proposed models then were calibrated using the collected data and validated quantitatively. The results indicated that the soil adsorption isotherms followed a linear form for both Pb and Cd concentrations. The results also indicated that the phytoremediation rate of Pb by Land Cress and Spinach are first-order function of Pb concentration in soil. In contrast, a zero-order function of soil Cd contaminations was obtained. Combining these two results of soil and plant responses to Pb and Cd pollution, a simple model with reasonable performance was derived to predict the time needed for remediation of soil Pb (R2 > 0.98). However, in the case of Cd, the derived models appeared to be useful to make only some overall estimations of the remediation (R20.70).

 


A. Taebi, K. Jeirani, A. Mirlohi, A.r. Zadeh Bafghi,
Volume 11, Issue 42 (1-2008)
Abstract

  Some industrial processes, such as plating and gold mining, utilize cyanide, which entering in their effluents. Because cyanide compounds are toxic contaminants, the waste-containing cyanide must be treated before discharge in the environment. Several methods are available for cyanide removal or detoxification. Natural degradation, alkaline chlorination, and oxidation with hydrogen peroxide are the most common methods in full-scale plants. Because of technical and economical concerns related to these methods, biological treatment processes have recently come under consideration. In phytoremediation, plants potential for pollutant removal is used. The main objective of present study is to investigate feasibility and potential of phytoremediation of cyanide-polluted soils by non-woody plants. The experiments carried out in this study were a completely random factorial design procedure, with three replications. Three non-woody plants: sorghum (as a cyanogenic cereal plant) and fescues with and free of endophyte (as grasses), were examined. Analysis of variance of the data obtained on soil cyanide reduction and cyanide accumulation in plants showed that phytoremediation is a suitable technique for low concentration of cyanide-polluted soils. Besides, it was been found that sorghum has a better soil cyanide removal efficiency than fescues, so that a significant portion of soil cyanide will accumulate in sorghum tissues.


N. Toomanian, H. Khademi , A. Jalalian,
Volume 12, Issue 44 (7-2008)
Abstract

Determination of landscape evolution is useful to well understand the physical environment and it also enables us to conduct the soil related studies. The objective of this study was to establish the historic evolution of Zayandeh-rud Valley from late Tertiary to Quaternary. To achieve this objective, the spatial structure of a representative area of Zayandeh-rud Valley in three dimensions was examined. Responsible geologic and geomorphic processes of landscape formation were determined and inherited records and evidences of changes in soil development were investigated. The inherited foot marks and different analyses proved that following the Zayandeh-rud River formation, from Miocene to present time, the following processes and events have occurred during valley formation pathway: 1- formation of old gypsiferous gravelly alluviums, 2- lagoon formation, the change in the river pathway, 3- playa formation, 4- river terrace deposition and 5- starting of wind erosion.
E Marouf Pour, H Moazed, H.a Kashkouli, H Moahamad Vali Samani,
Volume 12, Issue 46 (1-2009)
Abstract

Tracer experiments are very important in the studies related to aquifer contamination for determination of dispersion coefficient. In this study, the effect of sampling method on the dispersion coefficients of two simulated sandy aquifers was examined. The physical model was made from Plexiglas material with inner length, width and height of 72, 10 and 120 cm, respectively. A solution containing 9 g/l sodium chloride (Ec = 14 ds/m) was used as the non - reactive (conservative) contaminant. Homogeneous sands with coarse and medium particle sizes were used as media for the simulated aquifers. The experiments were carried out in the aquifers with various thicknesses from 20 to 100 cm with 10 cm thickness increment. Point and mixed samples were taken through all experiments. The results of the study showed that (1) for both simulated aquifers, the dispersion coefficient values obtained by point sampling method were close to the values obtained by other researchers from laboratory experiments (2) In all the experiments, the dispersion coefficient values obtained by mixed sampling method were higher than those obtained by the point sampling method (3) with increasing the aquifer thickness, the dispersion coefficient values obtained from the mixed samples varied but did not have a uniform trend which could be due to the unavoidable experimental errors and (4) there was no difference between the breakthrough and pore volume curves of various aquifer thicknesses obtained from point and mixed samples. Overall, based on the results obtained from this research, in studies related to aquifer contamination, it is recommended to take point samples instead of mixed samples to obtain more precise results.
F Goodarzi,
Volume 12, Issue 46 (1-2009)
Abstract

Because of its tenderness, long distance between field and consumer locations and unsuitable condition of transportation, 30 – 40 percent of strawberry fruits is wasted during the transportation between field to markets. One of the recommended ways for cutting down the wastes of strawberry is application of calcium salts after harvest stage to increase the content of Ca2+ in fruit flesh. For this reason, the selected fruits were treated by immersing them in 0, 25, 50 and or 75 mmol/lit concentrations of CaSO4, CaCl2 or Ca(NO3)2 for 4 min. After drying in atmospheric tempetature, fruits were stored at 5°C for 5 and for 10 days. To evaluate the effect of calcium solutions on fruit quality, some quantitative and qualitative tests were carried out on them. The results showed that by increasing the concentration of calcium salts, the amount of acidity and calcium of fruits is significantly increased, but the percentage of mouldy fruits is decreased. In most cases, the 50 and 75 mmol /lit concentrations of CaSO4 showed similar effects. Among the different calcium solutions, Ca(NO3)2 had the best effect on improvement of fruit quality, such as increasing the calcium and firmness of fruit , but CaSo4 prohibited the moulding of fruits better than other solutions. By increasing the period of storage from 5 to 10 days, the amount of acidity and firmness decreased significantly, while mouldness percentage increased. The organoleptic test showed that when the concentration of CaCl2 and Ca(NO3)2 solutions is increased, the acceptability of treated samples is decreased by consumers. Because of the bitter taste, the least score was given to the samples treated by 75 mmol/lit concentration of Ca (NO3)2 solution. The panelists didn’t recognize any difference in taste between control and samples treated by 25 mmol/lit concentration of CaSO4 and CaCl2 solutions. None of the treatments showed initial attributes (tenderness and shape) of fruits after storage period. This method isn't recommended to increase the strawberrys' shelf life for home use, but it can be used for the ones which are to be consumed in food processing industries.
F Khajali, R Bagheri,
Volume 13, Issue 48 (7-2009)
Abstract

The present experiment was carried out to determine the effect of feeding a diluted diet together with avilamycin or probiotics on catch-up growth of broiler chickens. Three hundred day-old chicks (Ross 308 hybrid) were assigned to 4 treatments with 5 replicates based on a completely randomized design. The control group, which met NRC requirements, fed a diet consisting of 2900 KCal/kg ME and 20.8%CP. A diluted diet included 2700 KCal/kg ME and 19.4%CP fed to the negative control group during 7 to 21 days of age. There were two additional treatments with 10ppm avilamycin and 100ppm probiotic, respectively. Feeding the diluted diet resulted in reduced body weight gain (P<0.05). Final body weight was higher in chickens having received avilamycin. Although this difference was insignificant compared with the control, it was significant in comparison with other groups. There was no significant difference in terms of feed intake among the treatments. However, birds which received avilamycin had superior feed conversion ratio to other groups. Birds in the control group had the highest abdominal fat content but the difference was not significant. In conclusion, avilamycin significantly increased body weight gain during catch-up growth though the probiotic caused no significant change.

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