Meteorological elements affect the dynamics of air pollutants, where
these elements can play an important role in dispersing and
transferring air pollutants as well as to photochemical reactions of
secondary air pollutants.
This study was conduct
ed to analyze the effect of several
meteorological variables on the concentrations of some air pollutants
(Co, NO2, SO2, O3, PM10) at two sites in Damascus city, by using the
Pearson correlation coefficient.
The under keel clearance (UKC) is considered as one of the most important factor
which governs the navigation safety in restricted waterways. However, the notion of safe
under keel clearance is directly related to ship sinkage. The recent researche
s to evaluate
ship sinkage show that it is related to vessel potential energy. The curve of vessel
displacement in heave motion as function of potential energy shows that a ship has three
equilibrium positions; stable equilibrium position represents steady squat and unstable
equilibrium position which can be considered as a virtual bottom for a ship, the third stable
equilibrium position does not have any physical signification, since it lies below the
bottom.
The principal goal of this paper is to develop a mathematical model for vessel motion
during acceleration phase by considering several assumptions. Then, analyze the
conversion of kinetic energy to potential energy at the unstable equilibrium position during
acceleration phase. By taking into account the period during which the vessel accelerates
as well as the vessel speed at the end of the acceleration phase. The results show that ship
stability could be affected by the oscillations generated at the end of this phase.
Three sampling stations were chosen along the lower reach section of AlSanawbarriver (Lattakia-Syria). In these stations, the freshwater molluscs were studied, environmentally and taxonomically, during the period 4/3/2012 – 4/8/2013.
In this resea
rch, I present the results of the environmental study on the Gastropod Valvatasaulcyiwhich was more abundant in the 3rd station; 5km of the estuary.
Ten mollusc species were identified; 8 belonging to Gastropoda (4 of Prosobranchia & 4 of Pulmonata) and 2 belonging to Bivalvia.
The chemical and physical properties of the water in the 3rd station were studied and the work was concentrated on Valvatasaulcyipopulation and structure, where samples were collected bimonthly during Spring, summer & autumn and monthly during winter. It was shown that reproduction of such species is continuous along the year, with 2 reproduction beaks: the more important one is spring beak and the less important one is autumn beak.
The population structure of the species was studied: shell dimensions were measured and the relationships were studied between height growth and breadth growth of the shell, and between the breadth growth and dry weight of the individual ….
