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Edaphic properties and soil cyanobacteria of South Western Saudi Arabia.
(
Qatar University
, 1997 , Article)
Three sites at each of five localities, in the South Western Region of Saudi Arabia were surveyed during 1992, for their soil physico-chemical properties, and cyanobacterial communities. The soils were moderately calcareous, ...
Changes in carbohydrate and nitrogen fractions during germination of fenugreek (Trigonellafoenum-graecum L.) seeds presoaked in GA3, growing under different osmotic potentials
(
Qatar University
, 1997 , Article)
Changes in carbohydrate and nitrogen fractions during seed germination of fenugreek under water stress and GA^ treatment were investigated. The germination percentage was reduced with the decrease in the osmotic potential ...
A rational logarithmic model for unconstrained non-linear optimization
(
Qatar University
, 1997 , Article)
A new non-quadratic model is proposed for solving unconstrained optimisation problems which modifies and develops the classical conjugate gradient methods. The technique has the same properties as the classical conjugate ...
Effects of electric and magnetic fields on the energy levels of a hydrogenic impurity in GaAs/Gal-xAl x As heterjunction
(
Qatar University
, 1997 , Article)
Variational method within the effective — mass approximation is used to calculate the shallow impurities states in GaAs / Gai_xAl^As heteroj unctions. Modified Fang-Howard wavefunction is used as the trial wavefunction. ...
The role of radiogenic heat in maturation of organic matter within oil shales of Duwi formation in Quseir-Safaga District, Red Sea coastal area, Egypt
(
Qatar University
, 1997 , Article)
The oil shale beds of Duwi Formation at Quseir-Safaga district in Egypt show a high content of organic matter (kerogen) and a fair pyrolysis oil yield. Kerogens of these rocks are composed mainly of marine amorphous and ...
Geochemical studies using trace elements analysis of source rocks and related crude oil in the Gulf of Suez, Egypt
(
Qatar University
, 1997 , Article)
The occurrence and distribution of trace elements in source rocks and crude oils is used to asses the process of geochemical exploration. Rock and crude oil samples representing the giant fields of the Gulf os Suez province ...
Bayes Estimation of the Parameter of Burr Type II Distribution in Case of Type II Censoring
(
Qatar University
, 1997 , Article)
Suppose that Xj, X2, ..., Xn is a random sample of failure times from a Burr type II (B2) distribution
with parameter 9. Let x = (xj, x2, , xr) with xj < x2 S x3 < < xr be the observed failure censored
sample of the first ...
Phyllosphere and phylloplane fungi of some herbal plants belonging to Labiatae, Solanaceae and Umbelliferae in Egypt
(
Qatar University
, 1997 , Article)
Survey on the occurrence of phyllosphere and phylloplane fungi on leaves surface of 15 different kinds of fresh herbs (three samples of each kind) belonging to three plant families (five kinds belonging to each of Labiatae, ...
Characterization of Polymers in Dilute Solutions
(
Qatar University
, 1997 , Article)
Basic moleculer characterisitics of polymers are: molecular architecture, molecular weight and size, and their distributions. All these characterisitics are derived from measurements of very dilute solutions. Methods of ...
A Mixed Markovian Time Series Model
(
Qatar University
, 1997 , Article)
We study a simple time series model the noise properties of the proposed model are derived. An algorithm based on the conditional mean and the conditional variance, for estimating the parameters of the proposed model is ...