Abstract: The effect of magnetic field on germination
characteristics of two wheat Seeds has been studied under laboratory
conditions. Seeds were magnetically exposed to magnetic field
strengths, 125 or 250mT for different periods of time. Mean
germination time and the time required to obtain 10, 25, 50, 75 and
90%of seeds to germinate were calculated. The germination time for
each treatment were in general, higher than corresponding control
values, in the other word in treated seeds time required for mean seed
germination time increased nearly 3 hours in compared non treated
control seeds. T10 for doses D5, D6, D11 and D12 significantly higher
than the control values for both cultivars. Mean germination time
(MGT) in both cultivars significantly increased when the time of
seed exposed at magnetic field treatments increased , about 3 and 2
hour respectively for Omid and BCR cultivars.
Abstract: In order to study of The Effect of seed inoculation
with Pseudomonas putida+Bacillus lentus on yield and yield
components of wheat (Triticum aestivum L.) cultivars, an experiment
was carried out as factorial based on Randomized Complete Block
Design (RCBD) in Agricultural Research Station of Shahrood
University of Technology. Results showed that inoculation with
Pseudomonas putida+Bacillus lentus promoted seed germination.
Also, inoculation with Pseudomonas putida+Bacillus lentus
significantly affected grain yield, Number of spikes per m2,
Number of grain per spike and 1000-seed weight and There was not
statistically significant difference between Chamran and Pishtaz
cultivars . Finally, the dosages of chemical fertilizers currently
applied in commercial wheat field in Iran (Shahrood region) could be
reduced through proper combination of Pseudomonas
putida+Bacillus lentus inoculation plus fertilization.
Abstract: High voltage generators are being subject to higher
voltage rating and are being designed to operate in harsh conditions.
Stator windings are the main component of generators in which
Electrical, magnetical and thermal stresses remain major failures for
insulation degradation accelerated aging. A large number of
generators failed due to stator winding problems, mainly insulation
deterioration. Insulation degradation assessment plays vital role in the
asset life management. Mostly the stator failure is catastrophic
causing significant damage to the plant. Other than generation loss,
stator failure involves heavy repair or replacement cost. Electro
thermal analysis is the main characteristic for improvement design of
stator slot-s insulation. Dielectric parameters such as insulation
thickness, spacing, material types, geometry of winding and slot are
major design consideration. A very powerful method available to
analyze electro thermal performance is Finite Element Method
(FEM) which is used in this paper. The analysis of various stator coil
and slot configurations are used to design the better dielectric system
to reduce electrical and thermal stresses in order to increase the
power of generator in the same volume of core. This paper describes
the process used to perform classical design and improvement
analysis of stator slot-s insulation.
Abstract: In order to study of hydropriming and halopriming on
germination and early growth stage of wheat (Triticum aestivum) an
experiment was carried out in laboratory of the Department of
Agronomy and Plant breeding, Shahrood University of Technology.
Seed treatments consisted of T1: control (untreated seeds), T2:
soaking in distilled water for 18 h (hydropriming). T3: soaking in -
1.2 MPa solution of CaSO4 for 36 h (halopriming). Germination and
early seedling growth were studied using distilled water (control) and
under osmotic potentials of -0.4, -0.8 and -1.2 MPa for NaCl and
polyethylene glycol (PEG 6000), respectively. Results showed that
Hydroprimed seeds achieved maximum germination seedling dry
weight, especially during the higher osmotic potentials. Minimum
germination was recorded at untreated seeds (control) followed by
osmopriming. Under high osmotic potentials, hydroprimed seeds had
higher GI (germination index) as compared to haloprimed or
untreated seeds. Interaction effect of seed treatment and osmotic
potential significantly affected the seedling vigour index (SVI).
Abstract: Today with the rapid growth of telecommunications equipment, electronic and developing more and more networks of power, influence of electromagnetic waves on one another has become hot topic discussions. So in this article, this issue and appropriate mechanisms for EMC operations have been presented. First, a source of alternating current (50 Hz) and a clear victim in a certain distance from the source is placed. With this simple model, the effects of electromagnetic radiation from the source to the victim will be investigated and several methods to reduce these effects have been presented. Therefore passive and active shields have been used. In some steps, shielding effectiveness of proposed shields will be compared. . It should be noted that simulations have been done by the finite element method (FEM).
Abstract: Today with the rapid growth of telecommunications equipment, electronic and developing more and more networks of power, influence of electromagnetic waves on one another has become hot topic discussions. So in this article, this issue and appropriate mechanisms for EMC operations have been presented. First, impact of high voltage lines on the surrounding environment especially on the control room has been investigated, then to reduce electromagnetic radiation, various methods of shielding are provided and shielding effectiveness of them has been compared. It should be expressed that simulations have been done by the finite element method (FEM).
Abstract: High voltage generators are being subject to higher
voltage rating and are being designed to operate in harsh conditions.
Stator windings are the main component of generators in which
Electrical, magnetically and thermal stresses remain major failures
for insulation degradation accelerated aging. A large number of
generators failed due to stator winding problems, mainly insulation
deterioration. Insulation degradation assessment plays vital role in the
asset life management. Mostly the stator failure is catastrophic
causing significant damage to the plant. Other than generation loss,
stator failure involves heavy repair or replacement cost. Electro
thermal analysis is the main characteristic for improvement design of
stator slot-s insulation. Dielectric parameters such as insulation
thickness, spacing, material types, geometry of winding and slot are
major design consideration. A very powerful method available to
analyze electro thermal performance is Finite Element Method
(FEM) which is used in this paper. The analysis of various stator coil
and slot configurations are used to design the better dielectric system
to reduce electrical and thermal stresses in order to increase the
power of generator in the same volume of core. This paper describes
the process used to perform classical design and improvement
analysis of stator slot-s insulation.
Abstract: Optimal selection of electrical insulations in electrical
machinery insures reliability during operation. From the insulation
studies of view for electrical machines, stator is the most important
part. This fact reveals the requirement for inspection of the electrical
machine insulation along with the electro-thermal stresses. In the
first step of the study, a part of the whole structure of machine in
which covers the general characteristics of the machine is chosen,
then based on the electromagnetic analysis (finite element method),
the machine operation is simulated. In the simulation results, the
temperature distribution of the total structure is presented
simultaneously by using electro-thermal analysis. The results of
electro-thermal analysis can be used for designing an optimal cooling
system. In order to design, review and comparing the cooling
systems, four wiring structures in the slots of Stator are presented.
The structures are compared to each other in terms of electrical,
thermal distribution and remaining life of insulation by using Finite
Element analysis. According to the steps of the study, an optimization
algorithm has been presented for selection of appropriate structure.
Abstract: The heterotrophic seedling growth can be defined as a
product of two components: (1) the weight of mobilized seed reserve,
and (2) conversion efficiency of utilized seed reserve to seedling
tissue. The first component can be further divided into (1) initial seed
weight, and (2) the fraction of seed reserve, which is mobilized. The
objective of this study was the identification of the sensitive seedling
growth component(s) in response to drought and salinity stresses.
Two experiments were separately conducted using various salinity
levels (osmotic pressure) of 0, 0.25, 0.50, 0.75, 1, 1.25 and 1.5 MPa
created using NaCl as first experiment and by polyethylene glycol
(drought stress) of 0, 0.2, 0.4, 0.6, 0.8, 1, 1.2 and 1.4 MPa in second
experiment. Seeds of five crops species (Hordeum vulgare, Brassica
napus, Zea mays, Medicago sativa and Medicago scutellata) were
used in each experiment. In both experiments, seedling growth,
fraction of seed reserve utilization and weight of mobilized seed
reserve decreased with increasing drought and salt intensity.
However, drought and salinity stresses had no effect on the
conversion efficiency. It was concluded that the sensitive component
of seedling growth is the weight of mobilized seed reserve.