Showing 6 results for Gum
M. Mahlooji, S.f. Mousavi, M. Karimi,
Volume 4, Issue 1 (4-2000)
Abstract
A study was conducted to determine irrigation scheduling of pinto bean and to evaluate the effect of its planting date. A split-plot with complete randomized block design with four replications was used at Isfahan University of Technology Research Station in Shervedan-Falavarjan, The main plots were three irrigation regimes of T1 to T3 (irrigation after 50±3, 70±3 and 90±3 mm evaporation from class A pan, respectively) and the sub-plots were two planting dates of May 28 and June 28.
The results showed that delayed planting from May to June caused earlier flowering, physiological maturity and reduction of 29.6% in grain yield. Grain yield in T1 to T3 treatments were 3585.1, 3510.5 and 1925.8 kg/ha, respectively. The difference between grain yields of T1 and T2 with T3 treatments were significant at 1% probability level. Biological yields at May 28 and June 28 planting dates were 8257.1 and 5535 kg/ha, respectively, which were significantly different. There was no significant difference between biological yields of T1 and T2 treatments. Number of pods per square meter was the most important component of grain yield and 85% of grain yield difference was due to this part. Harvest index was affected by irrigation treatment and planting date. Mean harvest indices for T1 to T3 treatments were 45.5, 46.1 and 37%, respectively, and 42.8% and 44.9% for the two planting dates. Water use efficiencies for grain yield in T1 to T3 treatments were 0.557, 0.556 and 0.329 kg/m3, respectively. Generally, treatment T2 was shown to be the best irrigation regime.
Sh. Amirkavei, H. Fatemi, M. A. Sahari,
Volume 8, Issue 3 (10-2004)
Abstract
Low calorie salad dressings are oil-in-water emulsion products, in which the oil content has been substantially decreased. This decrease, however, is accompanied by reduction in the viscosity hence, an undesirable texture. To overcome this, oil replacers are generally used. In this research, maltodextrin and xanthan gum were used to replace part of the oil in the production of two kinds of salad dressings mayonnaise and three Italian salad dressing. Various formulations of these products with varying amounts of oil, maltodextrin and gum at different temperatures were produced. Viscosities in the range of 50-140 Pa.s for mayonnaise and 2-15 Pa.s for Italian dressing were accepted as positive criteria and samples in these ranges were chosen for organoleptic and microbial tests.
The results showed that in the formulation of mayonnaise, simultaneous increase in the amount of oil, maltodextrin and gum created a high viscosity, but the temperature did not play any significant role. In the Italian salad dressing, the increase in the amount of gum was accompanied by development of pseudoplastic characteristics which was not desirable, hawever, the effect of temperature on providing acceptable texture was found to be important. Although the formulated mayonnaise enjoyed a fairly acceptable quality, the Italian salad dressing samples, were ranked superior to the common Italian salad dressing available in the Iranian market.
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B. Maherani, M. Barzegar, M. A. Sahari, H. Dehghan,
Volume 8, Issue 4 (1-2005)
Abstract
Aqueous extraction of gum from flaxseed was optimized using Response Surface Methodology (RSM). In this study the effect of temperature (45-100 °C), pH (3-7) and water/seed ratio (4-24), on the dependent variables including: yield, protein and apparent viscosity of extracted gum were investigated. The results showed that temperature and pH are two major effective factors on yield and quality of extracted gum (purity and apparent viscosity), whereas water/seed ratio had minor effects. The optimized conditions of extraction were as follows: temperature 85- 90 oC pH 6.5- 7.0 and water/seed ratio 14. Apparent viscosities of extracted gums were determined and the effect of extraction conditions on rheological properties of flaxseed gum was investigated.
H.r. Moradi, M. Vafakhah , A. Akbari Baviel,
Volume 11, Issue 42 (1-2008)
Abstract
Discharge routing as a mathematic process to forecast the changes of greatness, speed and form of flood wave is function of time in one or more points along drainage, canal or reservoir. Hydrologic and hydraulic methods are used to accomplish the flood routing. Although hydrologic method is less accurate than hydraulic methods but it is simpler to use in flood control and designing works with acceptable confidence. This study has been conducted for flood routing in Lighvan River from Lighvam hydrometric station to Hervy hydrometric station in eastern Azerbaijan Province in a distance the 12 Km. The discharge for different return periods (2, 10, 20, 50 and 100 years) was calculated by using upstream stations data. Then routing of every flood discharge was studied with different return periods by Muskingum and Muskingum-Cunge methods. Results showed significant difference between calculated discharges routing by two methods with discharge values to relate that return period in Hervy hydrometric station. The reasons of exist this different, is numerous for example mountain location this area and to exist sub drainage in between two stations and etc.
V. Rezaei, S. S. Eslamian, J. Abedi Koupai, A. R. Gohari,
Volume 28, Issue 2 (8-2024)
Abstract
The relationship between intensity-duration-frequency of rainfall is a significant tool for estimating flood discharge. According to the sparsely available rain gauge stations and the development of technology, it is possible to use satellite rainfall data with different temporal and spatial resolutions. PERSIANN rainfall data with a time resolution of 1 and 6 hours were used in this research. Also, the spatial resolution of these data is 0.04 x 0.04 degrees. Rainfall data from synoptic stations around the Kan basin were also used. Three common continuous probability distributions of Gamble, Pearson type 3, and Log Pearson type 3 with return periods of 2, 5, 10, 25, 50, and 100 years were investigated to calculate and check the IDF curve. In general, the precipitation intensity obtained from Gumble's method was more than Pearson Type 3's method. Log Pearson type 3 distribution did not provide acceptable results in this research. The two interpolation methods of inverse distance weighting and empirical Bayesian kriging were used to generalize the frequency intensity curves to the entire Kan basin. The results showed little difference between these two methods, except for Pearson type 3 probability distribution.
M. Amiri, E. Fazel Najafabadi, M. Shayannejad,
Volume 28, Issue 3 (10-2024)
Abstract
One of the important issues in river engineering is flood trends. In general, two types of methods are used to determine the flood trends in rivers. The first group of hydraulic methods, such as the dynamic wave method, is based on solving continuity and momentum equations or Saint-Venant equations. The second category is hydrological methods like the non-linear Muskingum method. In this research, both methods have been used to determine the trends of flood hydrographs in the Plasjan River, one of the main tributaries of the Zayandehrud River. The coefficients of the non-linear Muskingum method were obtained by optimizing and solving the related equation with the fourth-order Runge-Katai numerical method using MATLAB software and the dynamic wave method using the two-dimensional HEC-RAS software. In this study, four flood events were used. In the non-linear Muskingum method, the first event was used for model calibration and the other three events were used for validation. The error rate in this method for the second, third, and fourth events was 84.23, 6.6, and 7.96 percent, respectively, and the error rate in the dynamic wave method for these four events was 17.58, 87.3, 5.4, and 6.21 percent, respectively. Therefore, the dynamic wave method is more accurate in estimating the output hydrograph. However, the non-linear Muskingum method has acceptable accuracy and is recommended in terms of cost, required information, simplicity, and speed of calculation in situations where sufficient information is not available.
