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Journal of Renewable Materials 2023年第5期11卷 2109-2123页

作者： Ruaa H.Abbas a.kadhim Azhar M.Haleem Laser and Optoelectronics Engineering Department University of Technology-IraqBaghdadIraq Environmental Research Center University of Technology-IraqBaghdadIraq

Copper oxide nanoparticles(CuO NPs)were synthesised with laser ablation of a copper sheet immersed in deionized water(DW),cetrimonium bromide(CTAB),and sodium dodecyl sulphate(SDS),*** target was irradiated with a pulsed Nd:YAG laser at 1064 nm,600 mJ,a pulse duration of 10 ns,and a repetition rate of 5 *** CuO NPs colloidal were analyzed using UV–Vis spectroscopy,the Fourier transform infrared(FTIR)spectrometer,zeta potential(ZP),X-ray diffraction(XRD),transmission electron microscope(TEM)and field emission scanning electron microscopy(FESEM).The absorption spectra of CuO NPs colloidal showed peaks at 214,215 and 220 nm and low-intensity peaks at 645,650 and 680 nm for SDS,CTAB and DW,*** NPs’colloidal results are(−21.6,1.2,and 80 mV)for negatively,neutrally,and positively charged SDS,DW,and CTAB,*** XRD pattern of the NPs revealed the presence of CuO phase planes(110)(111),(20-2)and(11-1).The TEM images revealed nearly spherical NPs,with sizes ranging from 10–90,10–50,and 10–210 nm for CuO NPs mixed with DW,SDS and CTAB,*** images of all the synthesized samples illustrate the formation of spherical nanostructure and large particles are *** CuO NPs were tested for antibacterial activity against Streptococcus mutans by using the well diffusion *** this method,CuO NPs prepared in DW at a concentration of 200μg/mL showed a greater inhibition zone against Streptococcus mutans.

关键词： Copper oxide nanoparticles(CuO NPs) laser ablation Streptococcus mutans

Improving Crude Oil Flow Using Graphene Flakes under an Applied Electric Field

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2067-2081页

作者： Thaer Al-Jadir Laith S.Sabri Wafaa a.kadhim Saja Mohsen Alardhi Raheek I.Ibrahim Environment Research Center University of Technology-IraqBaghdadIraq Chemical Engineering Department University of Technology-IraqBaghdadIraq Nanotechnology and Advanced Materials Research Center University of Technology-IraqBaghdadIraq Electromechanical Engineering Department University of Technology-IraqBaghdadIraq

Graphene flakes(GF)have been prepared and assessed as a material for improving flow in oil pipelines under the effect of an electric *** particular,different amounts of GFs have been considered in order to determine the optimal flow *** GFs were prepared from graphite foam,derived from the dehydration of sugar with a particle size of 500-600μm,which was dispersed in ethanol and exfoliated in a ball mill under a shear *** 15 h of exfoliation,sonication,and subsequent high-speed centrifugation at 3000 rpm,irregular-shaped GFs of 50-140 nm were produced and characterized using scanning electron microscopy,X-ray diffractometry,atomic force microscopy,and Raman *** prepared graphene sheets have been found to display excellent morphology and good graphitic *** on flow improvement were conducted using the central composite rotatable design method for three parameters:stimulation time(15,30,45,and 60 s),applied voltage(150,170,200,and 220 V),and concentration of the GFs(0,100,200,and 400 mg/L).The optimal conditions for improved crude oil flow were then determined using the STATISTICA and WinQSB software *** results have confirmed the effectiveness of the use of the prepared GFs as a flow improver for crude oil,where the flow improvement is essentially a result of a reduction in viscosity and suppression of friction in the crude oil system.

关键词： Graphene flakes flow improvement crude oil pipelines electrical field optimization

A Novel IoT Application Recommendation System Using Metaheuristic Multi-Criteria Analysis

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Computer Systems Science & Engineering 2021年第5期37卷 149-158页

作者： Mohammed Hayder kadhim Farhad Mardukhi Department of Computer Engineering and Information Technology Razi UniversityKermanshahIran

There are a variety of Internet of Things(IoT)applications that cover different aspects of daily *** of these applications has different criteria and sub-criteria,making it difficult for the user to *** requires an automated approach to select IoT applications by considering *** paper presents a novel recommendation system for presenting applications on the ***,using the analytic hierarchy process(AHP),a multi-layer architecture of the criteria and sub-criteria in IoT applications is *** architecture is used to evaluate and rank IoT *** a result,finding the weight of the criteria and subcriteria requires a metaheuristic *** this paper,a sequential quadratic programming algorithm is used to find the optimal weight of the criteria and sub-criteria *** the best of our knowledge,this is the first study to use an analysis of metaheuristic criteria and sub-criteria to design an IoT application recommendation *** evaluations and comparisons in the experimental results section show that the proposed method is a comprehensive and reliable model for the construction of an IoT applications recommendation system.

关键词： Internet of Things smart objects recommendation system multicriteria analysis sequential quadratic programming

Proactive Load Balancing Mechanism for Fog Computing Supported by Parked Vehicles in IoV-SDN

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China Communications 2021年第2期18卷 271-289页

作者： Ahmed Jawad kadhim Jaber Ibrahim Naser Ministry of Education General Directorate for Education in Al-QadisiyahAl-Qadisiyah 58002Iraq

Internet of Vehicles(IoV)is a new style of vehicular ad hoc network that is used to connect the sensors of each vehicle with each other and with other vehicles’sensors through the *** sensors generate different tasks that should be analyzed and processed in some given period of *** send the tasks to the cloud servers but these sending operations increase bandwidth consumption and *** computing is a simple cloud at the network edge that is used to process the jobs in a short period of time instead of sending them to cloud computing *** some situations,fog computing cannot execute some tasks due to lack of ***,in these situations it transfers them to cloud computing that leads to an increase in latency and bandwidth occupation ***,several fog servers may be fuelled while other servers are *** implies an unfair distribution of *** this research study,we shall merge the software defined network(SDN)with IoV and fog computing and use the parked vehicle as assistant fog computing *** can improve the capabilities of the fog computing layer and help in decreasing the number of migrated tasks to the cloud *** increases the ratio of time sensitive tasks that meet the *** addition,a new load balancing strategy is *** works proactively to balance the load locally and globally by the local fog managers and SDN controller,*** simulation experiments show that the proposed system is more efficient than VANET-Fog-Cloud and IoV-Fog-Cloud frameworks in terms of average response time and percentage of bandwidth consumption,meeting the deadline,and resource utilization.

关键词： IoV parked vehicles SDN fog computing load balancing

Practical solution for stabilized pseudo-steady state productivity index of multiple vertical wells depleting closed reservoirs

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Petroleum 2020年第1期6卷 53-69页

作者： Salam Al-Rbeawi Fadhil S.kadhim METU-Northern Cyprus Campus Cyprus University of Technology Iraq

The objective of this paper is introducing practical solutions for stabilized pseudo-steady state productivity index and pressure behaviors and flow regimes of multiple vertical wells depleting closed rectangular *** introduces full understanding of reservoir performance during transient and pseudo-steady state flow using pressure and pressure derivative patterns and productivity index and productivity index derivative *** practical solutions proposed in this study are relied on a new approach for accurate estimation of starting time of pseudo-steady state flow and stabilized productivity index by applying productivity index derivative that converges mathematically to zero at the beginning of this *** is also an attempt for pointing out the optimal reservoir configuration that can give maximum stabilized pseudo-steady state productivity index for different wellbore types and distributions in the drainage *** analytical models are used in this study for describing pressure drop and productivity index behavior of multiple vertical wells considering different reservoir configurations and different wellbore types and *** wells were assumed either fully or partially penetrate the *** pressure models are justified to generate two pressure derivatives,one represents the derivative of time dependent pressure drop and the second represents the derivative of time-invariant pressure *** two derivatives are used for determining the starting time of pseudo-steady state flow and stabilized productivity index when both converge and mathematically become *** models are used also to generate several plots for time-invariant or stabilized pseudo-steady state productivity index for different reservoir geometries considering different wellbore *** maximum stabilized productivity index is illustrated in these plots and several analytical models for the expected flow regimes are developed using pressure a

关键词： Pressure behavior and flow regimes Reservoir characterization Reservoir performance Vertical wells Modeling and simulation Productivity index

Amorphous/Crystalline （n-n） Si Heterojunction Photodetector Made by Q-Switched 0.532-mm Laser Pulses with Novel Technique

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Chinese Physics Letters 2006年第2期23卷 370-373页

作者： Raid A. Ismail kadhim A. Hubeatir Abdullah K. Abass Department of Applied Physics Ministry of Technology Baghdad Iraq Department of Optoelectronics University of Technology Baghdad Iraq

Amorphous/crystalline n-n-isotype Si heterojunetions are made by a pulsed Q-switched second harmonic generation Nd：YAG laser. The process includes melting and subsequently fast resolidification of a thin front layer of monocrystalline Si by laser pulses to create an amorphous layer （phase transition）. Different laser energy densities are used to form the amorphous layer on a monocrystalline Si substrate, the results of the electrical characteristics of the heterojunctions are dependent strongly on the laser energy density. Optoelectronic properties such as current-voltage, capacitance voltage, and spectral sensitivity are measured in a-Si/c-Si hereto junctions （in the absence of anti-reflecting coating and frontal grid contact） prepared by different laser energy densities. The built-in-potential values extracted from current-voltage measurements are close to the published results of （n-p） amorphous/crystalline hereto junction made by glow discharge and plasma enhanced chemical vapour deposition. Furthermore, examination of the formation of amorphous pattern on Si surface is carried out with the help of optical microscopy. Best photovoltaic performance is recognized to be at ,5.6 J/cm^2. The photodetector shows a wide spectral response, and the peak response is at 780nm. On the other hand, this peak is independent of laser energy.

关键词： CRYSTALLINE SILICON SOLAR-CELLS

The impact of hydraulic flow unit & reservoir quality index on pressure profile and productivity index in multi-segments reservoirs

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Petroleum 2017年第4期3卷 414-430页

作者： Salam Al-Rbeawi Fadhil kadhim METU-Northern Cyprus Campus Cyprus University of Technology Iraq

The objective of this paper is studying the impact of the hydraulic flow unit and reservoir quality index(RQI)on pressure profile and productivity index of horizontal wells acting in finite *** mathematical models have been developed to investigate this *** models have been built based on the pressure distribution in porous media,depleted by a horizontal well,consist of multi hydraulic flow units and different reservoir quality *** porous media are assumed to be finite rectangular reservoirs having different configurations and the wellbores may have different *** analytical models describing flow regimes have been derived wherein hydraulic flow units and reservoir quality index have been included in addition to rock and fluid *** impact of these two parameters on reservoir performance has also been studied using steady state productivity *** has been found that both pressure responses and flow regimes are highly affected by the existence of multiple hydraulic flow units in the porous media and the change in reservoir quality index for these *** change in the RQI could lead to positive change in both pressure drop required for reservoir fluids to move towards the wellbore and hence the productivity index.

关键词： reservoir reservoirs index

Detection of Laser-Produced Tin Plasma Emission Lines in Atmospheric Environment by Optical Emission Spectroscopy Technique

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Photonic Sensors 2017年第4期7卷 289-293页

作者： kadhim A. AADIM Department of Physics College of Science University of Baghdad Aljadiriya Campus Baghdad 00964 Iraq

A spectroscopic study on laser-produced tin plasma utilizing the optical emission spectroscopy （OES） technique is presented. Plasma is produced from a solid tin target irradiated with pulsed laser in room environment. Electron temperature is determined at different laser peak powers from the ratio of line intensities, while electron density is deduced from Saha-Boltzmann equation. A limited number of suitable tin lines are detected, and the effect of the laser peak power on the intensity of emission lines is discussed. Electron temperatures are measured in the range of 0.36eV-0.44eV with electron densities of the order 1017cm-3 as the laser peak power is varied from 11 MW to 22 MW.

关键词： Tin plasma laser-produced plasma electron density electron temperature

The impact on alpha emission rates of varying distances between a CR-39 detector and alpha-emitting bone samples

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Radiation Detection Technology and Methods 2021年第4期5卷 618-626页

作者： Nada Farhan kadhim Yasser Ayad kadhim Rasha S.Ahmed Ali A.Ridha Mostafa Y.A.Mostafa Department of Physics College of ScienceMustansiriyah UniversityBaghdadIraq Department of Physiology College of MedicineAl-Nahrain UniversityP.O.Box 70010AlkadhimiyaBaghdadIraq Physics Unit Science DepartmentRustaq College of EducationUniversity of Technology and Applied SciencesMuscatSultanate of Oman Physics Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt Ural Federal University Mira Street 19YekaterinburgRussia620002

Background Changing the distance between a sample and an exposed solid-state nuclear track detector affects the number of alpha tracks recorded by the *** concept had been used to distinguish high-energy alpha particles by computing the alpha emission rate at two distances(0 and 2 cm)from animal bone *** and methods Two Cr-39 detectors were placed in a container with bone ash inside to measure the alpha emission rate when the detectors were in contact with the ash and hung at a distance of 2 cm from the *** The alpha emission rate was found to be 62.7×10^(−4) Bq cm^(−2) when the detector was in contact with the sample(a small exposure area)and 324.4×10^(−4) Bq cm^(−2) when the sample was placed 2 cm away(a larger exposure area).A mathematical equalization of the exposure areas was conducted(the area of the detector exposed to the alpha emitter sample at a distance of 2 cm was equalized to the area exposed when in contact with the sample).After equalization,a reduction in the average value of the alpha emission rate from 324.4×10^(−4) to 17.4×10^(−4) Bq cm^(−2) was *** The increase in distance between the sample and the detector allowed only high-energy alpha particles with a range greater than the traveled distance to reach the ***,this system can distinguish the type and number of nuclides in the sample by changing the distance between the detector and the sample according to each nucleus ***,the results show that the alpha emission rates in these bone samples are higher than the local values.

关键词： Radioactivity Animal bone CR-39 detector Track density Alpha range

An Evaluation to the Performance of Evacuated Tube Solar Heaters for Arid and Hot Areas

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Energy Engineering 2023年第3期120卷 587-596页

作者： Asaad H.Sayer Samah Hussein kadhim Hameed B.Mahood Department of Chemistry College of ScienceUniversity of Thi-QarNasiriyahIraq Centre for Sustainable Cooling School of Chemical EngineeringUniversity of BirminghamBirminghamUK

Solar energy applications could be the best alternative to the conventional fuels for the purposes of domestic,water and space heating and some industries in the sunny,arid,and hot *** the present study,the performance of an evacuated tube solar heater for water heating for months of February and March was experimentally *** was performed in a hot and arid area(Nasiriya City,South of Iraq).A solar heater with ten evacuated tube solar collectors with a capacity of 100 liter was used in the *** evacuated tube had a length of 1.8m with an outside diameter of 8 *** was observed that for the two selected months,water temperature of the solar heater reached a maximum more than 70°C during sunny days with no heat extraction from the tank of the solar ***,heat was extracted from the solar collector with four different flowrates 0.5,0.75,1,and 1.25 l/min,*** results showed that temperature of the solar heater behaved differently from the static *** the heat extraction begun,there was a gradual and noticeable decrease in the water temperature of the *** observed decrease was slight with the lowest flowrate(0.25 l/m)and becomes sharp with the highest flowrate(1.25 l/min).However,water temperature of the solar heater remained higher than 40°C for the investigated flowrates except the case of 1.25 l/*** results showed that evacuated tube solar heater can work efficiently in arid and hot areas in winter and spring seasons when the conditions of solar radiation are suitable.

关键词： Solar energy evacuated tubes solar collectors