bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of Effective Parameters in Stability and Vibration of Marine Propulsion Shafting Systems
Authors: Hussain Aboud Aqeel Abdul , Ali Jaafar Khalaf 
Published: August 2021

Abstract
The marine propulsion system is a system that a ship depends on in travelling and maneuvering in the existence of different types of waves, which reduce the efficiency of the system. In this work, different types of vibration such as torsional, lateral and longitudinal and their effect on ship and propulsion system are studied. Vibration seriously threatens the reliability and safety of the ship. The finite element method is established to study vibration at different rotational speeds. In this work vibration, analysis and modeling with simulation for cases of lateral and torsional vibration are performed by using MatLab software. In addition, ANSYS 2019 R3 is used to study some cases of marine propulsion system. In this work, effective parameters that play important role in vibration reduction such as the diameter, stiffness, couple unbalance and mass unbalance are discussed. The results of that analysis provided can help to predict the problems. In general, to achieve better stability and safety, all the conditions of the propulsion system must be taken into account to diagnose the problem. Hence, the data which are provided in diagrams and tables can be used as a guide in the design stage or maintenance stage to treat system problem and then take the proper action.
An investigation of the effect of walnut shell as sand replacement on the performance of cement mortar subjected to elevated temperatures
Authors: Mohammed Abdulrahman S , Hilal Nahla N , Mohammed Ali Taghreed Khaleefa , Sor Nadhim Hamah 
Published: August 2021

Abstract
This study examined the effect of ground shells of walnut (GW) as fine aggregate on the fresh and hardened properties of cement mortar before and after being subjected to elevated temperatures. The experimental work consists of two series with different water to cement ratio (w/c) and various percentages of GW. In each series, the ratios of GW were varied in range (0-30% at an increment of 10%). The fresh density and slump test were used as fresh properties and the dry density with compressive strength were measured at the curing ages of 7, 14 and 28 days as hardened characteristics. Also, the dry density and compressive strength at 28 days curing age were examined after exposure to an elevated temperature of 400 °C and 600 °C for two hours. The results indicated that the all tested properties were reduced by using GW. The optimum utilized ratio of GW is 20% for the first series with w/c of 0.5 which led to producing lightweight cement mortar and is suitable for structural purposes before and after exposure to 400 °C. However, the rest of the mixtures are suitable for non-structural purposes.
Evaluation of Quenching and Tempering on Cutting Force and Surface Finishing of Steel Machining
Authors: Alfatlawi Sattar Hantosh A. , Jodia Wafa Mahdi 
Published: August 2021

Abstract
In this paper, quenching and tempering effects on the machining conditions of medium carbon steel were investigated. The samples were quenched in a saltwater and polymer solution after heated to austenitizing temperature at 870°C, then, the tempering process of the samples were conducted to reduce internal stresses and hardness. In the tempering process the samples were heated again to 400°C with a soaking time was one hour, so cooled in still air. So the samples were machined by lathe machine with selected cutting conditions. The results appeared the effect of heat treatments on hardness, surface finishing, cutting force and microstructure that were evaluated before and after heat treatment with various cutting conditions.
Studying the nonlinear optical properties of organic dyes after Dissolved in Methanol and Epoxy Resin
Authors: Ibrahim Slafa I , Yaseen Hanaa Mohammed , Nader Rajaa 
Published: August 2021

Abstract
In this paper, some linear optical properties such as (absorbance and transmittance) of an organic dye (Calcein -W) in Methanol and Epoxy resin with different concentration were studied by using UV/VIS spectrum.
Nonlinear optical properties of Calcein –W anesthetized in epoxy resin matrix using different concentrations (5*10−5, 1*10−4, 5*10−4, 1*10−3 mol/l) at ambient temperature were studied by using open and closed aperture of Z-scan technique, with continuous wave from Neodymium-doped Yttrium Garnet (Nd: YAG (CW)) laser beams of 532 nm wavelength as an excitation source. The “nonlinear refractive index” (n2), “nonlinear absorption coefficient” (β) of Calcein –W doped film is experimentally determined.
Magnetic and Dielectric Properties of Epoxy Composites Reinforced with Hybrid Nanoparticle iron oxide (Fe3O4) and nickel (Ni)
Authors: Kaadhm Ehab Q , Salman Khansaa D , Reja Ahmed H 
Published: August 2021

Abstract
In this research, the effects of hybrid nanoparticles Fe3O4+Ni on the magnetic and dielectric properties of epoxy resin are investigated. Microstructural characterization was performed by Field Emission scanning electron microscopy FESEM, X-ray diffraction spectra XRD, and Fourier-transform infrared spectroscopy (FTIR). The magnetic properties were investigated by vibrating sample magnetometer (VSM) and the dielectric response was investigated by a precision impedance analyzer (Agilent 4294A) LCR meter at room temperature with different frequencies. The study dealing with hybrid nanocomposite (epoxy/Fe3O4+Ni) consisting of epoxy resin as the matrix material reinforcing by magnetite nanoparticles (Fe3O4) with different weight percentages (3wt.%, 6wt.%, 9wt.%, 12wt.%, 15wt. %) and constant weight percentage 2wt% of nickel (Ni) nanoparticles. The samples were prepared using the casting method. The epoxy with the hardener is weighted and mixing in a 2:1 ratio and then add reinforcement materials Fe3O4+Ni into the epoxy. Microstructural analysis showed that a uniform distribution and homogeneously dispersed in the epoxy matrix. The results of this work exhibit that the Increasing additive weight percentages of Fe3O4 nanoparticles with a constant weight of Ni nanoparticles into epoxy resin led to improvement in the magnetic and electric properties of hybrid nanocomposites compared with pure epoxy.
Numerical study on Built-up Steel Columns Behavior
Authors: Taheir AL-Tai Maan M. , Al-Sulayfani Bayar J. , Mohammad Khalaf I. 
Published: August 2021

Abstract
This study investigates the behavior of Built-up steel columns. The effect of shape, distribution, and angle of inclination of the lacing have been studied, Finite element simulations are performed with ANSYS. A brick element with eight nodes and a shell element with eight nodes were adopted, After completing the study of the convergence between the laboratory analysis and the numerical analysis, the parametric study can begin by changing the dimensions of the lacing and the method of distributing the lacing in the structure of the manufactured steel column to make a comparison between the numerical analysis and the Experimental analysis for modeled models and determine the positive and negative points for each type of lacing used.
Investigation Electrical and Thermoelectrical properties of Ferrocene in staggered and eclipsed conformations
Authors: Hussein Thoalfkar Ali , Noori Mohammed D. 
Published: August 2021

Abstract
We present a comparative theoretical study of the electronic and thermoelectric properties of staggered and eclipsed ferrocene sandwiched between gold electrodes. These molecular junctions have been explored in two different configuration trans and cis conformation. In this work, we investigate the spin properties, in addition to thermoelectrical properties for all cases. Our results show that there is a variation in spin properties in staggered ferrocene when move from trans to cis configuration. However, in eclipsed ferrocene case there is no spin effects. Moreover, the room temperature electrical conductance in cis staggered ferrocene case is higher than other cases near the DFT Fermi energy. Furthermore, the thermopower of these junctions are rather high ranging about 150 µV/K. However, the thermoelectric figure of merit ZT of staggered ferrocene in cis configuration has the highest value with 1.06.
Improved Adhesion Bond between Asphalt Binder-Aggregate as Indicator to Reduced Moisture Damage
Authors: Hasan Ehsan A. , Abed Yasameen Hadi , Abedali Al-Haddad Abdulhaq H. 
Published: August 2021

Abstract
Improving the adhesion bonding strength between asphalt-aggregate combinations has a significant influence on the field performance and durability of asphalt pavement and minimizing the moisture damage that can appear in form of losing adhesion in asphalt-aggregate system by using modifiers will increase the service life of pavements.
The work of adhesion, de-bonding work, wettability and energy ratios were estimated based on surface free energy theory to evaluate the potential moisture-induced damage of combinations of pure and modified asphalt binders by (Styrene–Butadiene Styrene (SBS), Butyl Rubber (BR), and anti-stripping agent BG plus) with different types of aggregate. The sessile drop method is used to determine the components of the surface energy of different aggregate and asphalt binder types by performing direct contact angle measurements.
The experimental results showed that in general, the addition of SBS and BR modifiers will increase adhesion work and decrease de-bonding work and decrease ER2 and wettability for both types of asphalt binders and aggregates while the addition of an anti-stripping agent (BG plus) caused a reduction in adhesion work and de-bonding work and increase ER2 and wettability between the asphalt binder and aggregate surface and that will provide a better possible aggregate-asphalt binder bond strength and asphalt mixture’s resistance to moisture-induced damage.
Hybrid pv/t system performance based on the electrical and thermal efficiency in iraq
Authors: Hamad Karema.A. 
Published: August 2021

Abstract
Nowadays, solar energy is one of the important clean energies through converting the light sun into electricity by photovoltaic solar cells which is a semi-conducting material. Solar radiation is one of the most important factors in determining the amount of produced energy through absorbing it by the solar cells. On the other hand, heat is one of the sources of energy loss if it rises more than the prescribed limit, thus reducing the amount of electrical energy generated and reducing production efficiency. Therefore, this paper focuses on designing, testing and comparison the photovoltaic panel system (PVS) with and without Active cooling process via water in Baghdad environments. The active cooling system (ACS) was placed behind the solar cell in order to absorb the generated heat that is isolated from the environment. The testing of both models was conducted in April 2021 in Baghdad. As a result, PVS with cooling performed well compared with uncooled, where uncooled model at highest panel temperature produced about 8 % from operation efficiency. While, the ACS worked on increasing the system performance up to 16.5% by decreasing the panel temperature. The efficiency conversion has recorded to be 50% and 52% at two mass flow rates. Water flow rate increased the heat transfer through cover glass which led increasing the efficiency. Finally, ACS for PVS can improve the efficiency by about 12% as an average value. At high temperature environment, cooling system should be employed to get better PVS performance and reducing the payback period.
Mixed convection heat transfer in multi-Lid- driven trapezoidal annulus filled with hybrid nanofluid
Authors: Alesbe Israa , Ibrahim Sahira Hasan , Aljabair Sattar 
Published: August 2021

Abstract
Numerical study of mixed convection heat transfer in multi-Lid driven concentric trapezoidal annulus filled with H2O-Cu-Al2O3 hybrid nanofluid has been investigated. Three cases for multi-Lid driven have been studied: single lid-driven, double lid-driven move in the same direction, double lid-driven move in the opposite direction. The lid-driven walls move with a constant speed with constant cold temperature TC and the other inclined walls are insulated while the inner trapezoidal cylinder heated at constant temperature Th. Finite volume method used to solve the continuity, momentum, and energy equations by SIMPLE algorithm. The results validated by comparing with previous study with a good agreement of accuracy. The working fluids was: water with hybrid nanoparticles (volume fraction ϕ = 0 to 10%). The Richardson numbers changed from 0.01 to 10, to cover all convection heat transfer modes, and aspect ratios were 0.5 and 1. The results show that, the opposing flow produced highest maximum stream function. Moreover, in aiding flow (case 2) produced a heat transfer coefficient on the top and bottom walls of outer cylinder higher than that produced by the opposing flow (case 3). Generally, the skin friction increases with increase in the volume fraction of nanoparticles due to increasing the viscosity of fluid causes increase in shear stress and leads to increasing the pressure drop. Additionally, the aiding flow produced fiction factor higher than the opposing flow.
Improvement Corrosion Behaviour of Lean Duplex Stainless Steel 2101 alloy in Ringer solution by Plasma Nitriding for Biomedical applications
Authors: Al-Murshdy Jassim M.Salman , Hammood Ali Sabea , Fahad Nesreen Dakhel 
Published: August 2021

Abstract
“Plasma nitriding” is a surface hardening process that involves diffusion of the atoms of nitrogen onto the surface of metal under different plasma nitriding conditions. The new alloys used in the field of Biomedical applications are Lean Duplex Stainless Steel. The alloys of Lean DSS are corrosion resistant, lightweight, and have good mechanical properties such as fatigue strength, but in aggressive environments, they lack “wear resistance”. In a vacuum chamber of air (3 mbar), 400 V, and 30 mA, a lean duplex stainless steel (2101) alloy rod was plasma nitrided. The procedure of plasma nitriding was carried out at various times. The effect of plasma nitriding at different times (5, 10, 15, 20, 25) hrs on the chemical structure of LDX 2101 DSS alloy and the form of phases was investigated using OM, FESEM with EDS, XRD, and antibacterial test, tafel potential polarizaton and cyclic polarization for Orthopedic application. The results show that layers and phases S, Fe3N, and Fe2-3N were formed on the alloy’s surface, which would improve mechanical properties and corrosion resistance in Ringer solution at 37 °C.
Microstructure and Properties of Shape Memory NiTi Alloy
Authors: Salman Al-Murshdy Jassim M. , Ali Nareeman Yaseen 
Published: August 2021

Abstract
Many years ago, the shape memory alloys properties of Nickel Titanium (NiTi) were first discovered in the early 1960s, as shape memory alloys had many applied applications, in which oxidization problems were not of concern for the most part. However, over the past decades, NiTi alloys have been increasingly considered in external and internal biomedical devices, for example cardiac stent wires, orthodontics, vascular and bone fractures, fixing plates and screws, self-expanding urinary tracts.. The aim of the research is to study the effect of the elements mobidium and zirconium on the shape memory alloys. When adding small amounts of zirconium leads to a smoothing of the granular size, when adding Mobidium improves the hardening process. The alloy was prepared from primary powders of nickel and titanium, using metallic powder technology, under pressure of 800 MPa. Then the sintering method was carried out in a 4-10 tor vacuum at 950 ° C. The results upon XRD analysis revealed that NiTi were completely changed into NiTi (both cubic and mono phases) and Ni3Ti phase. The samples are ground in a dry atmosphere and the samples are polished after sintering. Optical microscopy, x-ray diffraction techniques. hardness test was conducted using Vickers hardness machine. It was observed that as the Zr content is increased, the hardness values, in VPN, increased. For instance, equi at 30% of Ni Ti had a hardness of 127.05 which increased significantly as Zr content was increased to 20 at %. This is mainly observed due to precipitation hardening which occurs due to the presence of multiple phase in alloy D. Increase in hardness also suggests that the workability. It was observed that as the Mo content is increased, the hardness values, in VPN, increased. For instance, Ni Ti had a hardness of 127.05 which increased was increased to 40at%. This is mainly observed due to precipitation hardening which occurs due to the presence of multiple phase in alloy G. Due to molybdenum, Optical microscopy reveals surface characteristics such as open pores and grain borders, as well as the distinction between the phases NiTi and Ni3Ti.
A modern technique to manage energy profile in Iraq: virtual power plant (VPP)
Authors: Kalaf A A , Alyozbaky O Sh , Alghannam A I 
Published: August 2021

Abstract
A virtual power plant (VPP) comprises decentralized generation integrated with energy storage and intermittent loads. Such a plant is an independently-controlled single production unit for the electrical grid and market. Frequency changes and power supply interruption are among the several scenarios that lead to peak grid loading. Considering the material and financial challenges, it is necessary to determine an optimal resource scheduling solution; VPP can address these challenges. This study evaluated two different domestic-sector situations in Iraq. MATLAB Simulink was used to simulate a VPP test system comprising loads, energy storage technology, and distributed generation. An analysis of the economic aspects concerning the network and involved resources was performed. The outcomes indicated that home electricity bills reduced by up to 50%. Simulations suggest that using VPP is beneficial as against distribution generators (DG) systems relying solely on intermittent renewable power generation.
An experimental study optimization of a solar assisted D.C refiergerter under Iraqi climate.
Authors: Omer Dalya Amjed , Mahdi Mahmoud Mustafa , Shuraiji Ahlam Luaibi 
Published: August 2021

AbstractSolar photovoltaic to derive a small dc domestic refrigerator is becoming beneficial for remote areas where electricity is not available. This article presents an experimental energetic and exergetic analysis for a small dc refrigerator driven by a solar photovoltaic (PV) panel. The performance parameters, such as exergy losses compressor, exergy losses condenser, exergy losses expansion valve, exergy losses evaporator, efficiency exergy refrigerator, average optimum exergy efficiency (refrigerator), efficiency system (PV panel plus dc refrigerator) were investigated. The mentioned parameters were measured along the time of the day under the climate of Baghdad city. The experimental test has been carried out with load refrigerator (5 liters of water), to the evaluate the average optimum value of the refrigerator exergy efficiency under different thermostat. this work aims to identify an optimal average exergy loss for D.C refrigerator during the day, which can work at the optimum condition in evaporator temperature. The average exergy losses optimum value in evaporated temperature (-6) is 24.63
Short Review on Reinforced Concrete Beam - Column Joint : Earthquake Response and Rehabilitation Techniques
Authors: Abbas Zinah Waleed , Shakir Hussam Raad , Al Jaberi Laith A. 
Published: August 2021

Abstract
It is highly recognized throughout the entire literature that there are many serious attempts to investigate the structural behavior of Reinforced concrete (RC) beam column joint. These studies tried to cover many key elements that usually govern the intended behavior of such structural element. It can be also from any simple survey during that literature that the reported failures in the past confirm the fact that the used design methods did not play the required role in providing good safe design. The most classic trend in strengthening the reinforced concrete joints was the addition of transversal bars. However, there are agreements throughout the recent contributions that increasing the level of reinforcement illustrated and optimum value and the extra addition may give negative results. In contrast, many alternative rehabilitation techniques were examined in the past such as Slurry Infiltrated Fiber Reinforced Concrete (SIFCON) blocks and Fiber Reinforced Polymer (FRP) sheets which gave good results regarding mechanical strength, stiffness and ductility behavior. The current study tries to present an overview with respect to past research programs that deals with such concern of science.
Air Purification and Water Generation Using A Compression Refrigeration System
Authors: Alsheekh Mohammed , Najim Saleh E. , Sultan Hussein S. 
Published: August 2021

Abstract
The prevention of coronavirus outbreaks requires cleaning and refreshing the closed environment where people live and operate. As a result, new environmental control methods must be developed. Also, water shortages represent an urgent problem, mainly countries that are island states and countries that have long coastlines which don’t have sufficient water resources such as lakes and rivers. This paper is an experimental, theoretical and numerical study of air purification and water generation by air conditioning and refrigeration equipment. The unit is based on a standard compressive cooling cycle principle. The experimental device will be established and tested in Basra city, south of Iraq, during September and August from 2020. The experimental device was tested for different days with different climatic conditions. Theoretical data has been completed by the (EES) program and the Numerical study by (ANSYS 2020R2) to verify and study more cases in a short time with no cost. The maximum production rate is 45.7 L/Day with the system’s performance factor of COP Max=4.0, Min=2.3, and Aver. =3.4. Therefore, the device can be used in coastal areas to meet water needs and provide a healthy environment.
Validation of a Three-parameters Hydrodynamic Model to Describe the non-ideal Flow in a Continuous Stirred Tank Reactor of the Electro-Fenton Oxidation of Organic Pollutants in Wastewater
Authors: Mahmood Raghad S. , Abbas Ammar S. 
Published: August 2021

Abstract
This research deals with the effect of the electrolyte flow behavior on electrochemical continuous stirred tank reactor performance. The reactor was simulated to remove organic pollutants from the wastewater and to determine the conditions for removal that will examine the effect of the electrolyte flow through the reactor. The flow behavior has been investigated using the pulse tracer technique at selected operating conditions. A model comprises three hydrodynamic parameters (bypass, active volume, and recirculation fractions) that have been used to analyze the residence time distribution. The modeling results indicate that with the increasing of the space-time, the bypass and the active volume fractions were decreasing, while the active volume of the reactor was decreasing. The obtained non-ideal space-time of the reactor using the hydrodynamic parameters and the relationship of the tracer concentration with time was much less than the ideal space-time, because of the great effect of bypassing fraction. Finally, the experimental results for the organic removal were closeted to the results that simulated at non-ideal space-time. This comparison proving a significant impact of non-ideal flow on the reactor performance, and showing that the proposed model was well-describing the behavior of the electrolyte through the reactor.