In this research we studied tricone drill bits by applying a
mathematical model which gives an analysis the effected factors on
its performance and efficiency(rate of penetration) , so we can
change these factors in valid allowable rang of operati
ng once ,
which it gives a positive impact on its performance which shorten
time and cost of drilling run , that has been in one of the Syrian oil
fields :Deir Ezzour petroleum company ..
Basalt is classified as a isotropic rock in according to its mechanical
properties. But gypsum is considered isotropic transverse rock . coming
the mechanical parameters values joins practice direction of parameters
.
By using a nondestructive me
thod such as the ultrasonic test which
depends on understanding the effectual of mechanical properties upon
speed of ultrasonics inside rocks , one can indirectly predict the
mentioned parameters
Tests were completed within 35 gypsum and 11 basalt rocks specimens
which collected by completions under the direction of General
Organization for Land Development ( Directorate of Geological
Investigation).
In this research, site investigations and tests were performed in
Khneifees phosphate mine. Samples of the studied rocks were
brought to the laboratory and tests were performed. The types of
these rocks are clayey limestone, organic limestone, white and gray
trepolite, opoka, chert and phosphate.The tests were performed
according to "American Standards for Testing of Materials"
(ASTM), and the recommendations of "International Society for
Rock Mechanics" (ISRM).
The objectives of this were to investigate the response of Lupinus albus sp. to
phosphate rock (PR) as a source of phosphorus (P) nutrition, and to study the role organic
acid (Citric and Malic) in phosphorus dissolution from PR. Tow experiments we
re
conducted: 1) A greenhouse pot experiment, in order to study the response of white lupin
to the application of PR and Triple super phosphate TSP at three application rates (100-
450-800 ppm). 2)- A laboratory experiment in order to study the role of Citric and Malic
acids concentration and initial pH in P- release from PR. The results showed that Lupinus
albus sp. was able to use PR for P-nutrition, and has a relative agronomic effectiveness of
61% when compared to TSP. The possible Exuded organic acids such as Citric and Malic
were responsible for PR dissolution due to tow mechanisms: 64% of PR dissolution was
due to pH decrease in the rhizosphere area, and 34% due to chelating of calcium cations.
PR dissolution was increased by the increase organic acid concentration, but decreased
when the initial pH value increased. Dissolution was always more pronounced with citric
than malic acid.
Rock slope failures usually occur along the structural
discontinuities in rock masses, but for weathered and highly
jointed rock masses, failure surfaces are often curved as in soil
slopes.
This paper is concerned with stability analysis of weath
ered and
highly jointed rock slope using shear strength reduction technique by FLAC program, which uses finite difference method.
This paper presents a stability analysis of a rock slope in Khneifees
mines in Syrian desert, to verify that it is safe for workers and
equipments to work beside it, and manipulates the result charts
of FLAC analysis using finite difference method and shear strength
reduction technique to assess the stability of the rock slope,
determine the safety factor of the rock slope and expect failure
mechanism.
A pot experiment was conducted to evaluate the relative agronomic
effectiveness (RAE%) of a Syrian phosphate rock when it is added alone and as
mixture with elemental sulfur with three different ratios (PR:S) (2:1) (5:1) (8:1)
and compared with tr
iple superphosphate. The main results of this study
showed that Ain Layloun phosphate rock was not effective for direct use by
Rye grass when used alone, but it became effective when mixed with elemental
sulfur. The relative agronomic effectiveness was varied following mixing ratios,
it was 50%, 76% and 87% in (8:1), (5:1) and (2:1) (PR:S) mixing ratios
respectively. This is due to the increase of available soil phosphorus content
which is related to the increase of phosphate rock solubility due to decrease of
pH derived from oxidation of sulfur by Thiobacillus spp.
A field experiment was carried out during 2003 and 2004 in Edleb
governorate to study the effect of phosphate solubilizing bacteria (Bacillus
megaterium) and cows manure on solubilization of phosphate rock, cotton
productivity, and phosphate uptak
e. The amounts of phosphate rock and
superphosphate were added by the same amount of P2O5.
An amount of nitrogen fertilizer as urea, was added to treatment 1, 2, 3, 4,
5, and 6 , whereas treatment 7, 8, 9, 10, 11, and 12 received amounts of organic
fertilizer having the same amount of N added to treatment 1-6 (MAAR
recommendation).
