Preferred Language
Articles
/
NuaJGp8BmraWrQ4dIW0h
Wellbore stability analysis and safe mud weight window selection in the Halfaya oil field
...Show More Authors

   Drilling operations in the Halfaya oilfield frequently encounter severe wellbore instability challenges. When navigating shale deposits, wellbore instability remains the primary operational concern. Based on the analysis of the wellbore instability intervals, low-strength shale and marlstone formations are identified as the principal unstable zones that lead to non-productive time and higher drilling costs. By planning a safe operating mud window, these non-productive times and drilling costs can be mitigated. Several wellbore instability concerns have been found in a southern Iraqi oil field. A problem-diagnostic technique was done by evaluating well log data, drilling reports, mud logging reports, and pore pressure readings. In wellbore stability evaluations, the three rock failure criteria that are used the majority of the time are the Mohr-Coulomb, Mogi-Coulomb and Modified Lade criterion were used to predict a safe mud weight window. The Mogi-Coulomb and Modified Lade criteria provided more accurate predictions than the Mohr-Coulomb model in well H1. The Mohr-Coulomb criterion proved inadequate for this formation because it fails to account for the intermediate principal stress. According to the pore pressure predictions in this study, the unsuitable mud weight of 10.49 ppg is the major cause of wellbore instability during the drilling of the Nahr Umr A formation in this well; therefore, a mud weight of 14.5–15 ppg is recommended. The Formation Micro Imager (FMI) was responsible for determining the orientations of the horizontal stresses. The Halfaya oilfield has an azimuth that corresponds to a maximum horizontal stress of about N20–35 E, the findings indicate that the Nahr Umr formation is characterized by a reversal faulting regime > > . Formation lithology impacts Halfaya oilfield horizontal stress. High-strength, hardened intervals have high horizontal stress, shale and marlstone formations with low strength are the principal unstable wellbore intervals. Ultimately, to prevent breakout failures and minimize drilling fluid losses, it is recommended to either restrict wellbore inclination or employ an optimized, higher mud weight.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Aug 01 2022
Journal Name
Baghdad Science Journal
Preparation, Spectroscopy, Biological Activities and Thermodynamic Studies of New Complexes of Some Metal Ions with 2-[5-(2-Hydroxy-Phenyl)- 1,3,4-Thiadiazol-2-Ylimino]-Methyl-Naphthalen-1-Ol]
...Show More Authors

This study describes the preparation of new series of tetra-dentate N2O2 dinuclear complexes (Cr3+, Co2+, Cu2+) of the Schiff base derived from condensation of 1-Hydroxy-naphthalene-2-carbaldehyde with 2-amino-5-(2-hydroxy-phenyl)-1,3,4-thiadiazole. The structures of the ligands were identified using IR, UV-Vis , mass,  elemental analysis and 1H-NMR techniques. All prepared complexes have been characterized by conductance measurement, magnetic susceptibility, electronic spectra, infrared spectrum, theromgravimatric analysis (TGA) and metal analysis by atomic absorption. From stoichiometry of metal to ligand and all measurements show a octahedral geometry proposed for all complexes of the (Cr3+, Co2+, Cu2+). conductivity measurement shows t

... Show More
Publication Date
Thu Jan 01 2026
Journal Name
Rsc Advances
Green biosynthesis of selenium nanoparticles by <i>Ralstonia insidiosa</i> which demonstrate effectiveness against human cancer cells, <i>Candida</i> species and multidrug-resistant <i>Acinetobacter baumannii</i>
...Show More Authors

Green biosynthesized selenium nanoparticles from Ralstonia insidiosa show potent activity against multidrug-resistant Acinetobacter baumannii , pathogenic Candida spp. and human prostate cancer cells.

View Publication
Scopus Crossref
Publication Date
Mon Aug 01 2022
Journal Name
Baghdad Science Journal
Preparation, Spectroscopy, Biological Activities and Thermodynamic Studies of New Complexes of Some Metal Ions with 2-[5-(2-Hydroxy-Phenyl)- 1,3,4-Thiadiazol-2-Ylimino]-Methyl-Naphthalen-1-Ol]
...Show More Authors

This study describes the preparation of new series of tetra-dentate N2O2 dinuclear complexes (Cr3+, Co2+, Cu2+) of the Schiff base derived from condensation of 1-Hydroxy-naphthalene-2-carbaldehyde with 2-amino-5-(2-hydroxy-phenyl)-1,3,4-thiadiazole. The structures of the ligands were identified using IR, UV-Vis , mass,  elemental analysis and 1H-NMR techniques. All prepared complexes have been characterized by conductance measurement, magnetic susceptibility, electronic spectra, infrared spectrum, theromgravimatric analysis (TGA) and metal analysis by atomic absorption. From stoichiometry of metal to ligand and all measurements show a octahedral geometry proposed for all

... Show More
View Publication Preview PDF
Scopus (25)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Fri Aug 15 2025
Journal Name
Baghdad Science Journal
Synthesis, Characterization, Biological Activity and Antioxidant Studies of New Metal Ion Complexes Based on (E)-4-((benzo[d]thiazol-2-ylimino)methyl)-1,5-dimethyl-2-phenylpyrazolidin-3-one
...Show More Authors

View Publication Preview PDF
Scopus Crossref
Publication Date
Wed Sep 02 2020
Journal Name
Indonesian Journal Of Chemistry
Synthesis, Characterization and Biological Efficacies from Some New Dinuclear Metal Complexes for Base 3-(3,4-Dihydroxy-phenyl)-2-[(2-hydroxy-3-methylperoxy-benzylidene)-amino]-2-methyl Propionic Acid
...Show More Authors

The reaction of methyldopa with o-vanillin in refluxing ethanol afforded Schiff base and characterized through physical analysis with a number of spectra also the study of biological activity. The geometry of the Schiff base was identified through using (C.H.N) analysis, Mass, 1H-NMR, FT-IR, UV-Vis spectroscopy. Metal complexes of Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+ with Schiff base have been prepared in the molar ratio 2:1 (Metal:L), (L = Schiff base ligand) except Hg2+ at molar ratio 1:1 (Hg:L). The prepared complexes were characterized by using Mass, FT-IR and UV-Vis spectral studies, on other than magnetic properties and flame atomic absorption, conductivity measurements. According to the results a dinuclear octahe

... Show More
Scopus (36)
Crossref (14)
Scopus Crossref
Publication Date
Wed Jan 25 2012
Journal Name
Synthesis, Characterization And Antibacterial Activities Of Some Metal (ii) Heterocyclic Polyamine Complexes With 6,6'-(1,4-phenylenebis(azanediyl) Bis(2- Amino-6-methyl-6h-1,3-oxazin-4-ol) Ligand.
Synthesis, characterization and Antibacterial activities of some metal (II) heterocyclic polyamine complexes with 6,6'-(1,4-phenylenebis(azanediyl) bis(2-amino-6-methyl-6H-1,3-oxazin-4-ol) ligand.
...Show More Authors

Preview PDF
Publication Date
Sun Dec 01 2024
Journal Name
Energy Storage
Comprehensive Study of <scp>PAN</scp>‐<scp>NaBF<sub>4</sub></scp> Solid Polymer Electrolytes: Insights Into Optical, Structural, Thermal, Electrical, and Electrochemical Properties for Sodium‐Ion Batteries
...Show More Authors
ABSTRACT<p>This research explores the use of solid polymer electrolytes (SPEs) as a conductive medium for sodium ions in sodium‐ion batteries, presenting a possible alternative to traditional lithium‐ion battery technology. The researchers prepare SPEs with varying molecular weight ratios of polyacrylonitrile (PAN) and sodium tetrafluoroborate (NaBF<sub>4</sub>) using a solution casting method with dimethyl formamide as the solvent. Through optical absorbance measurements, we identified the PAN:NaBF<sub>4</sub> (80:20) SPE composition as having the lowest energy band gap value (4.48 eV). This composition also exhibits high thermal stability based on thermogravimetric analysis results. </p> ... Show More
View Publication
Scopus (9)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Thu Nov 27 2025
Journal Name
Frontiers In Robotics And Ai
Design of modified fractional-order PID controller for lower limb rehabilitation exoskeleton robot based on an improved elk herd hybridized with grey wolf and multi-verse optimization algorithms
...Show More Authors

Rehabilitation robots are widely recognized as vital for restoring motor function in patients with lower-limb impairments. A Modified Fractional-Order Proportional-Integral-Derivative (MFOPID) controller is proposed to improve trajectory tracking of a 2-DoF Lower Limb Rehabilitation Exoskeleton Robot (LLRER). The classical FOPID is augmented with a modified control formulation by which steady-state error is reduced and the transient response is sharpened. Controller gains and fractional orders were tuned offline using a hybrid metaheuristic Improved Elk Herd Optimization hybridized with Grey Wolf and Multi-Verse Optimization algorithms (IElk-GM) so that exploration and exploitation are balanced. Superiority over the classical FOPID

... Show More
View Publication
Crossref (1)
Scopus Crossref
Publication Date
Wed Sep 02 2020
Journal Name
Indonesian Journal Of Chemistry
Synthesis, Characterization and Biological Efficacies from Some New Dinuclear Metal Complexes for Base 3-(3,4-Dihydroxy-phenyl)-2-[(2-hydroxy-3-methylperoxy-benzylidene)-amino]-2-methyl Propionic Acid
...Show More Authors

The reaction of methyldopa with o-vanillin in refluxing ethanol afforded Schiff base and characterized through physical analysis with a number of spectra also the study of biological activity. The geometry of the Schiff base was identified through using (C.H.N) analysis, Mass, 1H-NMR, FT-IR, UV-Vis spectroscopy. Metal complexes of Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+ with Schiff base have been prepared in the molar ratio 2:1 (Metal:L), (L = Schiff base ligand) except Hg2+ at molar ratio 1:1 (Hg:L). The prepared complexes were characterized by using Mass, FT-IR and UV-Vis spectral studies, on other than magnetic properties and flame atomic absorption, conductivity measurements. According to the results a dinuclear octahedral geo

... Show More
View Publication
Scopus (39)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Wed Apr 01 2020
Journal Name
Biochem. Cell. Arch.
SYNTHESIS, SPECTROSCOPIC IDENTIFICATION AND ANTIMICROBIAL ACTIVITY OF MIXED LIGAND COMPLEXES OF NEW LIGAND [3-((4- ACETYL PHENYL)AMINO)-5,5-DIMETHYLCYCLOHEX-2-EN-1-ONE] (HL* ) WITH 3-AMINO PHENOL
...Show More Authors

This work includes the synthesis and identification of ligand {3-((4-acetylphenyl)amino)-5,5-dimethylcyclohex2-en-1-one} (HL* ) by the treatment of 5,5-dimethylcyclohexane-1,3-dione with 4-aminoacetophenone under reflux. The ligand (HL* ) was identified via FTIR, Mass spectrum, elemental analysis (C.H.N.), 1H and 13C-NMR spectra, UV-Vis spectroscopy, TGA and melting point. The complexes were synthesized from ligand (HL* ) mixed with 3-aminophenol (A) and metal ion M(II), where M(II) = (Mn, Co, Ni, Cu, Zn and Cd) at alkaline medium to produce complexes of general formula [M(L* )(A)] with (1:1:1) molar ratio. These complexes were detected via FT-IR spectra, UV-Vis spectroscopy as well as elemental analysis (A.A) and melting point, conductivit

... Show More