Wellbore stability is considered as one of the most challenges during drilling wells due to the
reactivity of shale with drilling fluids. During drilling wells in North Rumaila, Tanuma shale is
represented as one of the most abnormal formations. Sloughing, caving, and cementing problems
as a result of the drilling fluid interaction with the formation are considered as the most important
problem during drilling wells. In this study, an attempt to solve this problem was done, by
improving the shale stability by adding additives to the drilling fluid. Water-based mud (WBM)
and polymer mud were used with different additives. Three concentrations 0.5, 1, 5 and 10 wt. %
for five types of additives (CaCl2, NaCl, Na2SiO3, KCl, and Flodrill PAM 1040) was used.
Different periods of immersion (1, 24 and 72 hours) were applied. The results of the immersion
test showed that using 10 wt. % of Na2SiO3 for WBM gives a high recovery percentage (77.99 %)
after 72 hr, while the result of the dispersion test (roller oven) of 10 wt % of sodium silicate with
WBM was (80.97 %) after 16 hr. Also, the immersion test result of 10 wt% of sodium silicate
with polymer mud was (79.76 %) after 72 hr and the results of dispersion test (roller oven) of 10
wt. % of sodium silicate with polymer mud was (84.51 %) after 16 hr.
Background: Molars and premolars are considered as the most vulnerable teeth of caries attack, which is related to the morphology of their occlusal surfaces along with the difficulty of plaque removal. different methods were used for early caries detection that provide sensitive, accurate preoperative diagnosis of caries depths to establish adequate preventive measures and avoid premature tooth treatment by restoration. The aim of the present study was to evaluate the clinical sensitivity and specificity rates of DIAGNOdent and visual inspection as opposed to the ICDAS for the detection of initial occlusal caries in noncavitated first permanent molars. Materials and Methods: This study examined 139 occlusal surface of the first permanent
... Show MoreThe effect of different Ti additions on the microstructure of Al-Ti alloy prepared by powder metallurgy was investigated. A certain amount of Ti (10wt%, 15wt%, and 20wt%) were added to aluminium and the tests like microhardness, density, scanning electron microscope (SEM), optical microscope (OM) and X-Ray Diffraction (XRD) were conducted to determine the influence of different Ti additives on the Al-Ti alloy properties and microstructure. The results show that the grains of α-Al changed from large grains to roughly spherical and then to small rounded grains with increasing Ti content, the micro-hardness of the alloy increases with increasing Ti, and XRD results confirm the formation of TiAl3 intermetallic co
... Show MoreThe increase globally fossil fuel consumption as it represents the main source of energy around the world, and the sources of heavy oil more than light, different techniques were used to reduce the viscosity and increase mobility of heavy crude oil. this study focusing on the experimental tests and modeling with Back Feed Forward Artificial Neural Network (BFF-ANN) of the dilution technique to reduce a heavy oil viscosity that was collected from the south- Iraq oil fields using organic solvents, organic diluents with different weight percentage (5, 10 and 20 wt.% ) of (n-heptane, toluene, and a mixture of different ratio
... Show MoreMonetary policy occupies a prominent role in achieving monetary stability by adjusting the growth rates of the number of available means of payment in line with changes in the size of the gross domestic product in the country and expressed by the monetary stability coefficient agreed upon by the International Monetary Fund, a term that hides the fact that there is a rate of change in the volume of commodity or real production which expresses the levels of aggregate supply in the economy, which corresponds to the quantities of cash in circulation, which represent a net purchasing power and stimulate aggregate demand, which completes the picture of the existence of the market mechanism, expressed by the monetary or economic stability
... Show MoreThe global trend towards the use of fair value accounting is increasing, so the current study aimed to maximize the impact of fair value application on achieving relevance and representation faithfulness of accounting information in accordance with the common conceptual framework. To achieve the objective of this study, the researcher has determined in the theoretical framework the relationship of fair value with the characteristics of relevance and representation faithfulness of accounting information and the extent of achieving these characteristics, as well as conducting a field study by preparing a questionnaire distributed to a sample of academics (50) and auditors (50) with a total number of selected participants (100) of acad
... Show MoreExperimental investigations had been done in this research to demonstrate the effect of carbon fiber and Ceramic fillers contents on the tribological behaviour of (15% volume fraction) carbon-epoxy composite system under varying volume fraction, load, time and sliding distance. The wear resistance were investigated according to ASTM G99-05standard using pin on disc machine to present the composite tribological behaviour. The influence of three ceramic fillers, granite, perlite and calcium carbonate (CaCO3), on the wear of the carbon fabric reinforced epoxy composites under dry sliding conditions has been investigated. The effect of variants in volume fraction, applied load, time and sliding distance on the wear behaviour of po
... Show MorePlant tissue culture techniques were exploited for the micropropigation of Lisianthus (Eustoma grandiflora). Different concentrations of Benzyl adenine (BA), 6- Furfural amino purine (Kinetin), Indol butyric acid (IBA), were investigated in their effects at different micropropagation stages. Three explants (apical shoots, internodes, leaf discs) were used in this study. The effect of the interaction between BA and IBA on shoot multiplication was investigated in increasing the number of shoots on explants. Rooting was also studied after inclusion of IBA and NAA to Murashige and Skoog, 1962 culture medium (MS). During acclimatization stage, different ratios of river sand and peat moss as agricultural media were tested and plantlets survival w
... Show MoreThe aim of this paper is to demonstrate the effect of Na2[Fe(CN)5.NO].2H2O impurity (0.1 M) concentration on the dielectrical properties of poly (P-Aminobenzaldehyde) terminated by pheneylenediamine in the frequency and temperature ranges (1-100)KHz and (283-348) K respectively.These properties include dissipation factor, series and parallel resistance, series and parallel capacitance, real and imaginary part of the dielectric constant, a.c conductivity and impedance (real and imaginary) part, that have been deduced from equivalent circuit. The investigation shows that adding Na2[Fe(CN)5.NO].2H2O as additive to the polymer lead to increase of the dielectric constant with increasing temperature and it is decreasing with increasing the freq
... Show MorePolyacrylamide Solutions of different concentrations (0.2, 0.4, 0.6, 0.8, 1.0 %) of Ag nanoparticles and ZnO nanoparticles were prepared, the viscosities and surface tension were measured for all solutions, where measurements indicated an increase in these properties with increased concentration, where the relative viscosity of polyacrylamide/zinc nanoparticles increased from 1.275 to 2.243, and the relative viscosity of polyacrylamide/silver nanoparticles increased from 1.178 to 1.934. Viscosity is significant parameters during electrospinning process. While the surface tension of the polyacrylamide/zinc nanoparticles has changed from 0.0343 Nm-1 to .0.0.0 Nm-1 and changed from .0.000Nm-1 to.0.0.0 Nm-1. Also the constants KH and KK were
... Show MoreThe effect of some environment faetor (different temperature and relative humidity) on the biology of the old world- screw worm, were studied under laboratory condition, the result showed that non of the eggs hatched at 15°c and under dried eondition which relative humidity between 20-40%, also result showed that the mature larvae needs one days to become pupa since it leaves the larval died at the temperature ranged between 25-40°C at different humidity rates. While it needs 3 days under lower temperature and different humidity to become pu^, on the other hand the results showed that either low temperature and dried condition or high temperature at different humidity rates cause non of pupa became adult. While low temperature (15-20) °c
... Show More