Traction force and power requirement when performing primary tillage occupy the minds of almost farmers, this field research had aim to determine and calculate the pulling force of the most commonly used moldboard and chisel plows, the research conducted in silt clay loam for chisel and moldboard plows as the main factor, two depths of tillage 18 and 25 cm as a second factor and three speeds of tractor 2.55, 4.30 and 6.15 km.h-1 as a third factor. Moldboard plow recorded least traction force 7.550 kN, drawbar power 11.583 hp, power losses due to slippage 1.088 hp, power on the rear axle of the tractor 15.770 hp and brake horse power 17.495 hp. Chisel plow recorded best traction efficiency 76.217 % and total traction efficiency 68.659 %. Depth of tillage 18 cm recorded least traction force 7.837 kN, drawbar power 12.190 hp, power losses due to slippage 0.986 hp. Speed tractor 2.55 km.h-1 recorded least traction force 8.246 kN, drawbar power 7.329 hp, power losses due to slippage 0.618 hp, resistance power losses due to motion 1.775 hp and power on the rear axle of tractor 9.723 hp. Correlation among performance indicators were positive and negative correlation significantly, also were insignificant correlation.
The purpose of this paper is to study the instability of the zero solution of some type of nonlinear delay differential equations of fourth order by using the Lyapunov-Krasovskii functional approach; we obtain some conditions of instability of solution of such equation.
The purpose of this paper is to study the instability of the zero solution of some type of nonlinear delay differential equations of fifth order with delay by using the Lyapunov-Krasovskii functional approach, we obtain some conditions of instability of solution of such equation.
In this paper, we proved that if R is a prime ring, U be a nonzero Lie ideal of R , d be a nonzero (?,?)-derivation of R. Then if Ua?Z(R) (or aU?Z(R)) for a?R, then either or U is commutative Also, we assumed that Uis a ring to prove that: (i) If Ua?Z(R) (or aU?Z(R)) for a?R, then either a=0 or U is commutative. (ii) If ad(U)=0 (or d(U)a=0) for a?R, then either a=0 or U is commutative. (iii) If d is a homomorphism on U such that ad(U) ?Z(R)(or d(U)a?Z(R), then a=0 or U is commutative.
The effectiveness inhibitory to extract alcohol for the leaf and flower to plant sage Salvia pratensis each of Staphylococcus aureus, streptococcus epidermidis, Salmonella typhi, Pseudomonas aeroginosa, Escherichia coli, Aspergillus niger and Candida albicans whom had any inhibition to aqueous extracts of the parts itself species bacterial and fungal. The study also demonstrated that the extract of plant containing compounds chemical such as tannins, Alkaloids, Flavonoieds, and saponins, which owns effectiveness of medical. The MIC, MBC and inhibition zones for crud extract were determinated for microbial agents.
The interlaminar fracture toughness of polymer blends reinforced by glass fiber has
been investigated. Epoxy (EP), unsaturated polyester(UPE), polystyrene (PS),
polyurethane (PU) and their blends with different ratios (10%PS/90%EP),
(20%PS/80%EP), (20%PU/80%EP) and (20%PU/80%UPE) were chosen as a matrices A
sheet of composites were prepared using hand lay -up method, these sheet were cut as the
double cantilever beam (DCB) specimen to determine interlaminar fracture toughness of
these composites .Its found that, blending of EP,UPE with 20% of PU will improve the
interlaminar fracture toughness ,but the adding of 10% PS, 20%PS to EP will decrease
the interlaminar toughness of these composites.
Gypsum is one of the important construction materials in Iraq in plastering surfaces and gypsum board , the ability of gypsum to give a comfortable an aesthetic ambiance as a construction material increase the need of gypsum , The particle size , total surface area and particle size distribution were factors affecting plaster properties used for construction properties . In this study gypsum paste was used with different mixing ratios of particle size and studied the physical properties of these types of pastes named (standard consistency ,setting time ,density) and compressive strength . The results showed that the water to gypsum ratio increased with increasing the fineness of the gypsum to (0.75%) and the setting time to the maxi
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(5)
(5)
In this work four complexes of antimony were prepared ,Na[SbO(gly)2],Na[SbO(Asp)2],Na[SbO(Tyrosin)2], Na [SbO(phen alanin)2]. by reaction SbOCl with salts amino acids identifiefid these complexes by FTIR ,their conductivity was measured and also their biological activity against two types of bacteria was studied ,they were biologically active.
A theoretical study by using computer model is presented to study the energy characteristics of the vibrational – rotational levels as a function of the vibrational and rotational quantum number, respectively. The calculations were based on the basis of a multilevel model taking into account the non-equilibrium population of the rotational levels. The computational investigation has been performed to examine the vibrational-rotational characteristics of some hydrogen halides chemical laser molecules. This program takes into account the various molecules of chemical lasers such as, Hydrogen Fluoride (HF), Deuterium Fluoride (DF), Hydrogen Chloride (HCl), and Deuterium Chloride (DCl). The practical difficulties associated with this
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