فهرست مطالب h. mohebbi

 Grape (Vitis vinifera L.) is one of the most important economic plants in the world including Iran. One of the most basic effective factors of the growth of fruit trees is knowing their nutrition. Micronutrients are as important as Macronutrients for better growth, yield and quantity in plants. Garden plants suffer from severe zinc deficiency, followed by boron, manganese, iron and molybdenum. Foliar application of fertilizers is a useful tool to increase the nutritional effects of fertilizers or eliminate nutrient deficiencies during the growing season. The aim of this study was to study the nutritional effects of consumption of different compounds of micronutrient fertilizers of zinc chelate, iron and manganese as foliar consumption on the morpho-physiological traits of grape plant.

 Field experiments were carried out to evaluate the effects of micronutrients alone and in combination on growth and fruit yield in grape grown at Iran, Zanjan province during 2016-18.  Physical and chemical properties of the soil were evaluated before the experiment. During the two years of the research, no organic or chemical fertilizers were used except for the combination of fertilizer treatments of the relevant design. Treatments consist of foliar consumption of micronutrients fertilizers included two levels of EDDHA-Zn (0.1 and 0.3 %), EDDHA-Fe (0.1 and 0.2 %), and EDDHA-Mn fertilizers (0.1 and 0.2 %) and control levels (0 %) for them. This experiment was implemented in a factorial format based on a randomized complete block design with three replications and repeated for two consecutive ys.  The measured traits consist of Length of the First inflorescence (X1), Number of Inflorescences per Branch (X2), Number of clusters per branch (X3), Number of Clusters per Plant (X4), Weight of a Cluster (X5), Cluster Size (X6), Berry Size (X7), Number of Berries per Cluster (X8), Weight of single Barry, X10: Leaf Area Surface. Leaf Dry Matter (X11), TSS (X12), Sugar Fruit Juice (X13), Fruit Juice Acidity (X14), Fruit Dry Matter (X15), Fruit Firmness (X16), Yield per Plant (X17), Yield per Hectare (X18). The experiment was performed in factorial format with three factors, each at three levels, based on a randomized complete block design with three replications in three locations (g; G) and in each location for two consecutive ys (Y). The analysis of each g was analyzed in the form of factorial experiment design and the effect of location factor was analyzed in the form of factorial-split (time) composite analysis in place. In the statistical model used, time and place factor considered as random and treatment was fixed.

 Evaluation of morpho-physiological traits showed that the use of these fertilizers individually or in combination has significant positive effects on all measured traits (18 traits) at different stages of development. The simple effect of the factor of the y was significant only on some of the measured traits and the two and three-way interactions between this factor with the levels of treatment in the majority of traits were not significant; which indicates the probability that the factor of the y has no effect on the measured traits. Based on these results, the treatment combination of Fe 0.2 + Zn 0.3 + Mn 0.2 % EDTA was superior to other combinations, and traits of the number of inflorescence and number of clusters per branch and number of clusters per plant showed the best response than other measured traits. Consumption of micronutrients, especially iron, zinc and manganese, has favorable effects on yield indices, better fruit formation and fruit production per unit area, which affects photosynthetic activities and important metabolic pathways in plants, leading to produce higher amounts of primary metabolites such as higher sugar production in fruit, increase in soluble solids, also increase in growth indices such as leaf area, more yield-related traits such as number of inflorescences and number of spikes per branch and per plant, number and the dimensions of the cube are in clusters. On the other hand, these compounds help to absorb the main nutrients and play an active role in initiating metabolic processes such as cell wall development, respiration, photosynthesis, chlorophyll formation, enzymatic activities, production of growth regulators, and nitrogen fixation and reduction. Accordingly, these compounds were able to show better performance compared to the control level by accelerating the absorption of other nutrients, strengthening biochemical pathways and growth indices.

 According to these results, the application of three fertilizers of zinc, iron and manganese EDTA individually or in combinations of two or three of them, especially at high concentrations simultaneously, is superior in comparison. And the treatment composition of 0.3% zinc + 0.2% iron + 0.2% manganese EDTA and then 0.3% zinc + 0.2% iron + 0.1% manganese EDTA has more significant and positive on measured traits and therefore as fertilizer compositions are recommended in vineyards in the form of leaves.

Flash sintering of 8 mol% yttria-stabilized zirconia (8YSZ) as solid oxide fuel cell (SOFC) electrolyte is studied. The relation between relative density, shrinkage, sample temperature during the flash, and incubation time, with the electric field strength, current density, as well as contact paste, are modeled by response surface methodology (RSM). The electric field strength and current density varied from 50 to 400V.cm-1 and 50 to 200mA.mm-2, respectively. Also, platinum (Pt) and lanthanum strontium manganite (LSM) used as contact paste. Results show that using LSM paste lead to higher density and more shrinkage compare with Pt paste. Contrary, the electric field strength has no significant effect on density and shrinkage. However, a minimum electric field strength equal to 80 V.cm-1 is necessary for flash onset. As the field increases, the incubation time decreases dramatically. Compare with samples with LSM paste, samples with Pt contact paste reach to a higher temperature during the flash. Flash sintered 8YSZ shows the mean grain size of 0.3μm, which is about half of the conventionally sintered 8YSZ. Electrochemical Impedance Spectroscopy reveals despite lower mean grain size, the resistivity of flash sintered 8YSZ is lower than conventionally sintered 8YSZ.

Using flawless components are important for a proper material selection and best working conditions to achieve the best performance of solid oxide fuel cells (SOFCs). Tape casting is the most used process for the fabrication of SOFC parts, especially anode and electrolyte due to its advantages regarding the other processes. In this study, the effect of slurry composition and milling time were successfully investigated on anode and electrolyte tapes defects. The results showed that the addition of terpineol to electrolyte slurry as a dispersant would reduce the size of agglomerates to 5μm. Furthermore, 6h of ball milling showed the optimum result for the anode slurry due to the disappearing of island defects, which agrees well with optical microscopy images of samples with minimum apparent defects on the surface. Afterward, the optimum tapes of anode and electrolyte were laminated and sintered at 1400°C for 4h. Half-cells had minimum apparent deformations and surface defects after sintering. Scanning electron microscopy images exhibited a uniform distribution of porosities without any separation in anode layers, as well as the full dense electrolyte.

Balance is a key component of motor skills ranging from maintaining posture to executing complex sport skills. The aim of this study was to compare static and dynamic balance in athletes of gymnastic, soccer, basketball, swimming and nonathletes. 40 female athletes with five years of athletic experience (gymnasts: n=10, age 14.50±0.31 years, height 155.20±7.75 cm, mass 49.70±3.91 kg, soccer players: n=10, age 22.80±1.45 years, height 160.60±5.12cm, mass 52.95±4.87kg, basketball players: n=10, age 21.60±1.07 years, height 165.5± 6.75 cm, mass 57.43±6.27 kg), swimmers: n=10, age 23.30±1.63 years, height 163.5±5.46 cm, mass 55.50±4.42 kg) and 10 female non-athletes (n = 10, age 23.70±0.94 years, height 161.40±3.27 cm, mass 54.60±3.54 kg and without athletic experience) participated in this study. Static balance was assessed using the balance error scoring system (BESS) and dynamic balance was assessed using the star excursion balance test (SEBT). Data were analyzed by ANOVA test (p≤0.05). BESS error scores for the gymnastics group were significantly lower than the swimming group and nonathlete group. These scores in the soccer group were lower than swimming group (p≤0.05). Star excursion balance test scores were higher in the gymnastics group than the basketball group and non-athlete group and in the soccer group than nonathlete group (p≤0.05). It was observed that swimmers enjoyed lower static balance and basketball players enjoyed lower dynamic balance; this may be a strong predictor of future ankle sprains. Therefore, athletic trainers and coaches are advised to perform regular screening programs using balance test of BESS and SEBT, and to assess the athletes’ balance so that they can recognize those with poor balance.