Acid treatment is a widely used stimulation technique in the petroleum industry. Matrix acidizing is regarded as an effective and efficient acidizing technique for carbonate formations that leads to increase the fracture propagation, repair formation damage, and increase the permeability of carbonate rocks. Generally, the injected acid dissolves into the rock minerals and generates wormholes that modify the rock structure and enhance hydrocarbon production. However, one of the key issues is the associated degradation in the mechanical properties of carbonate rocks caused by the generated wormholes, which may significantly reduce the elastic properties and hardness of rocks. There have been several experimental and simulation studies regarding the impact of acid wormholes on rock weakening in various carbonate rocks (chalk, limestone, and dolomite). However, considering the number of effective parameters which are associated with matrix acidizing, it is crucial to carefully monitor the acidizing procedure as well as perform a post-treatment evaluation of the targeted rocks. This work aims to review the fundamentals of matrix acidizing as a viable stimulation technique for carbonate rocks and provide deeper insight into the potential alterations in geo-mechanical properties. This review also evaluates a group of key parameters including acid type, injection rate, wellbore geometry, and rock type, and highlights the various analytical techniques used for acid stimulation evaluation in carbonate rocks.
Background: elastomeric impression materials are indicated when a high degree of accuracy is required, due to their excellent properties like details reproduction, dimensional stability and tear strength but with main two disadvantages those are their hydrophilicity as well as the absence of antibacterial activity. This study aimed to evaluate the effect of incorporation of 0.5% wt Ag-Zn zeolite into condensation silicone through the following tests; setting time, dimensional stability, reproduction of details, wettability, and hardness . Materials and methods: one hundred specimens were constructed of condensation silicone, divided into two groups for the first 50 specimens one0.5% by wt Ag -Zn zeolite was added, keeping the other fifty sp
... Show MoreGlobal warming and environmental damage have become major problems. The production of Portland cement releases large quantities of gas, which cause pollution to the atmosphere. This problem can be solved via the use of sustainable materials, such as glass powder. This study investigates the effect of partial replacement of cement with sustainable glass powder at various percentages (0, 15, 20, and 25%) by weight of cement on some mechanical properties (compressive strength, flexural strength, absorption, and dry density) of Reactive Powder Concrete (RPC) containing a percentage of Polypropylene fibers (PRPC) of 1% by weight. Furthermore, steam curing was performed for 5 hours at 90oC after hardening the sample directly. The RPC was
... Show MoreThe present research investigates joints welding of 304L austenitic stainless steel using metal inert gas (MIG) welding method. The research explores the effect of process parameters (arc voltage, wire feed rate, and electrode wire diameter) on the mechanical properties of stainless steel. The above variables are varied respectively with 18.5, 19, 19.5 V, 116, 127, 137 mm/s, and 0.8, 1, 1.2 mm, with E308L as a filler electrode. The design matrix of the experiments was determined using the design of experiment (DOE) program Minitab 17 based on the levels of input elements used. The Taguchi orthogonal matrix methodology (Taguchi) technique was used to develop some empirical analysis for the maximum tensile strength and proper surface
... Show MoreThe optimal design of any structural elements requires examining all environmental risks, emergency accidents, and standard load cases. Exposure to fire is one of the most common safety threats. Nowadays wide developments are achieved in the field of concrete technology, therefore, experimental and theoretical investigations should be performed on the characteristics of such developed materials under different loading conditions. This study investigates the impact of fire exposure on the mechanical characteristics of self-compacting concrete, specifically compressive and tensile strength, modulus of elasticity, and stress-strain relation. The adopted fire exposure consisted of six steady-state temperatures (300, 400, 500, 600, 700,
... Show MoreCdSe quantum dots possess a tuning energy gap which can control gap values according to the size of the quantum dots, this is made the material able to absorb the wavelengths within visible light. A simple model is provided for the absorption coefficient, optical properties, and optical constants for CdSe quantum dots from the size 10nm to 1nm with the range of visible region between (300-730) nm at room temperature. It turns out that there is an absorption threshold for each wavelength, CdSe quantum dots begin to absorb the visible spectrum of 1.4 nm at room temperature for a wavelength of 300 nm. It has been noted that; when the wavelength is increased, the absorption threshold also increases. This applies to the optical propertie
... Show MoreThe serum protein test includes measurement of the level of total protein(albumin, globulin). Fetuin-A is a blood protein made in liver. It can inhibit insulin receptor, enhance insulin sensitivity and make the individuals more likely to develop type 2 diabetes, then disorder in lipid profile (Total cholesterol(TC), low density lipoprotein cholesterol (LDL-c), high density lipoprotein cholesterol (HDL-c), Triglyceride(TG) and very low density lipoprotein cholesterol (VLDL-c) . To evaluate Fetuin-A, total protein, albumin, globulin, HbAlc and lipid profile in 200 adult and elderly Iraqi patients with type 2 Diabetes Mellitus were taken and compare them with 200 subjects as a healthy control. The laboratory analysis(for patients and
... Show MoreThis work investigates the properties of polyvinyl alcohol (PVA) nanocomposite films with varying multi-walled carbon nanotube (MWCNT) content, ranging from 2 to 8 wt.%. The films were prepared using a solution casting method and characterized using UV-visible spectroscopy, optical microscopy, X-ray diffraction, and tensile tests. The prepared PVA/MWCNT nanocomposite films exhibited optical band gap values ranging from 3.5 eV to 5.3 eV. XRD analysis confirmed the semi-crystalline nature of these nanocomposites. Mechanical properties, including hardness, yield strength, ultimate tensile strength, and Young's modulus, were enhanced by increasing MWCNT content by up to 8%. Contact angle measurements showed an increase in hydrophobicity with in
... Show MoreAbstract : This research has tackled about the role of Russia in the international policies which concerning with energy , So the most important states in the world that possesses huge energy resources to be more able in the control over the reality and future production programs and the distribution of global energy alike , the latter had effectively influence on the economic and developmental aspects within many countries in the world and its impacts on political decisions and perhaps effected too much in the dimensions of strategic policies . In this context of research , Russia has been developed a high energy policy of strategic planning in order to restoring Russia position and its global role by using its potential powerful streng
... Show MoreThis study aims to identify the concepts of financial crisis and its reasons of creation , also explain the effects of the accounting disclosure and the International Accounting Standards in current financial crisis, In addition to, indicate the role of accounting in the reform of the financial system from the impact of financial crisis.
The methodology of this study orientied to two main aspects, the first is an identifying approach through exploring the opinion of financial experts, the second aspect is based on an analytical approach to satisfy the requirements of experts to get there opi
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