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The effect of two substituents on different organoselenides and tellurides to form new charge-transfer complexes
(
Qatar University
, 2004 , Article)
Different organotellurides and selenides were prepared as electron donors and reacted with p-Benzoquinone (p-BQ) and m-Dinitrobenzene (m-DNB) as electron acceptors .
The resulted molecules were considered as new ...
Reduction kinetics of ceria surface by hydrogen
(
Elsevier
, 2004 , Article)
Sintered ceria pellets of porosity 16.4% and density 5.99gcm−3 were treated in a hydrogen flow at 1atm and various temperatures. The electrical conductivity was measured in situ while hydrogen gas was flowing over the CeO2. ...
Surface layer modification of ion bombarded HDPE
(
Elsevier
, 2004 , Article)
Press-moulded, high density polyethylene (HDPE) samples were subjected to ion bombardment and effects of the modification studied. He+ ions of energy 100 keV or Ar+ ions of energy 130 keV were applied in the range of dose ...
Risk assessment of accidental spills of toxic and flammable liquids on land
(
Emerald Publishing
, 2004 , Master Thesis)
The main objective of this paper is the assessment of the environmental impact due to accidental spills of toxic and flammable liquids on land. Different case studies of possible accidents in the State of Qatar were ...
Lumping Processes of Periodic ARMA Processes
(
Qatar University
, 2004 , Article)
In this article various lumping processes are defined for periodic ARMA (PARMA) processes, namely, the forward, the backward and the cyclic lumping processes. The inter-relations between the parameters of these lumping ...
C-Reactive Protein in the Premature Rupture of the Membranes
(
Hamad bin Khalifa University Press (HBKU Press)
, 2004 , Article)
Premature rupture of the membranes (PROM) defined as a rupture of membranes before onset of labor, which is one of the most complications of pregnancy that leads to significant maternal and neonatal morbidity and mortality. ...
Preparation, Characterization and Structural Determination of some coordination compounds of quadridentae thiosemicarbazone
(
Qatar University
, 2004 , Article)
New transtion metal complexes of Co", Ni" and Cu" with benzil bis 4-(p-Chlorophenyl-thiosemicarbazone) and benzil bis 4-(p-Bromophenyl-thiosemicarbazone) were synthesized. Attempts were made to ascertain their probable ...
Strain Broadening of E.P.R. Linewidths in Fe/Mgo Single Crystals and Powders
(
Qatar University
, 2004 , Article)
The E.P.R. linewidth of the M= + 1/2 <-» -1/2 transition of Fe3+ spectrum of Fe/MgO single crystals and powders have been measured at 9 GHz before and after annealing. The nominal iron concentrations ranged from 310 to ...
Determination and selecting the optimum thickness of insulation for buildings in hot countries by accounting for solar radiation
(
Elsevier
, 2004 , Article)
Determination and selecting the optimum thickness of insulation is the prime interest of many engineering applications. One of those applications is insulating buildings with an appropriate insulation. Calculations have ...
Application of Stripping Voltammetry for the Determination of Cadmium, Lead, Copper and Zinc in Yemani soils and Vegetables
(
Qatar University
, 2004 , Article)
Heavy metals contents in the solutions from acid digestion of Yemeni soils and vegetables were deter¬mined by differential pulsed anodic stripping voltammetry. The geometric mean for Cd, Pb, Cu and Zn concentrations for ...