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.
The multiple linear regression model is an important regression model that has attracted many researchers in different fields including applied mathematics, business, medicine, and social sciences , Linear regression models involving a large number of independent variables are poorly performing due to large variation and lead to inaccurate conclusions , One of the most important problems in the regression analysis is the multicollinearity Problem, which is considered one of the most important problems that has become known to many researchers , As well as their effects on the multiple linear regression model, In addition to multicollinearity, the problem of outliers in data is one of the difficulties in constructing the reg
... Show MoreFilms of silver oxide of different thickness have been prepared by the chemical spray paralysis. Transmission and absorption spectra have recorded in order to study the effect of increasing thickness on some optical parameter such as reflectance, refractive index , and dielectric constant in its two parts . This study reveals that all these paramters affect by increasing the thickness .
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... Show MoreThis article aims to explore the importance of estimating the a semiparametric regression function ,where we suggest a new estimator beside the other combined estimators and then we make a comparison among them by using simulation technique . Through the simulation results we find that the suggest estimator is the best with the first and second models ,wherealse for the third model we find Burman and Chaudhuri (B&C) is best.
In folk medicine there are various medicinal amalgamation possessing hepatoprotective activity. This activity is of significance because several toxins cause liver injury. Hence, many pharmaceutical companies are targeting herbal medicines for the treatment of liver abnormalities and towards evolving a safe and effective formulation with desired route of administration. In current review we have focused on the studies showing hepatoprotective effect using marine compounds and plant derived compounds. Liver disorder, a global health problem, usually include acute or chronic hepatitis, heptoses, and cirrhosis. It may be due to toxic chemicals and certain antibiotics. Uncontrolled consumption of alcohol also affects liver in an unhealthy wa
... Show MoreIn this paper, an approximate solution of nonlinear two points boundary variational problem is presented. Boubaker polynomials have been utilized to reduce these problems into quadratic programming problem. The convergence of this polynomial has been verified; also different numerical examples were given to show the applicability and validity of this method.
Many experiments were achieved to determine the allelopathic potential of the plant Myrtle parts in which it may affects other plants, like: volatile substances which released from the Myrtle leaves , and its effect examined on the germination (GE) and growth (GR) of the selected crops ; Chickpea ( C ) , Wheat(W) , and Lentil (L)., the aqueous extract of the leaf and the root of the plant examined to test its effect on the (GE) and (GR) of the selected crops ; (C) , (W) , and (L)., also plant residue of (M) and its effect tested on the (GE) and (GR) of the selected crops ; ( C ) , (W) , and (L) . Experiments proceeded on Spring 2007 in the greenhouse conditions , and main results which found were that; the effect of the volatile s
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