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Role of Ca^(2+) on Growth of Brassica campestris *** ***(L.) Czern & Coss under Na^+ Stress

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Journal of Integrative Plant Biology 2010年第6期52卷 549-555页

作者： Badr-uz-Zaman m.salim Rehana Asghar Land Resources Research Programme Institute of Natural Resources and Environmental SciencesNational Agricultural Research Centre Department of Botany University of Arid Agriculture

Root and shoot growth of Brassica campestris L. and B. juncea increased significantly （P 〈 0.01） with enhanced Ca2＋ treatment along with 60 mm NaCl in the root medium. The maximum fresh mass of shoot and root in *** was recorded at 10 mm Ca2＋ concentration. The relative growth rate of shoot of both species reached its maximum at 8 mm of Ca2＋ concentration. Average rate of Ca2＋ intake （lCa） was higher in B. juncea than 6. campestris. In B. juncea, the average transport of Ca2＋ to shoot increased by 19%, 38%, 119%, 125% and 169% compared with the control. Furthermore specific utilization rate of Ca2＋ was higher in B. juncea than B. campestris. In B. campestris it increased by 9%, 32%, 41% and 59% at 4, 6, 8, and 10 mm of calcium in comparison to 2 mm Ca2＋ treatment. At 4, 6, 8 and 10 mm of Ca2＋ application, the increase in the leaf area ratio was 10,17, 23 and 30%, respectively. In the shoot and root portions of B. campestris and ***, Ca2＋ had a linear relationship with potassium and sulfur, whereas it was in antagonism with sodium ion.

关键词： Coss under Na Czern Stress

Adsorption of lead and cadmium ions from aqueous solutions using manganoxide minerals

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Transactions of Nonferrous metals Society of China 2012年第12期22卷 3131-3139页

作者： Aylin SNmEZAY m.salim NCEL Nihal BEKTAS Gebze Institute of Technology Department of Environmental Engineering

Removal of lead and cadmium ions from aqueous solutions by adsorption process was investigated. Low cost and locally available natural mineral of manganoxide mineral was used as an adsorbent. The kinetics of adsorption process data was examined using the pseudo-first-order, pseudo-second-order kinetics and the intra-particle diffusion models. The rate constants of adsorption for all these kinetics models were calculated and compared. The adsorption kinetics was best described by the pseudo second-order model. The Langmuir and Freundlich adsorption isotherm models were applied to the experimental equilibrium data at different temperatures. The experimental data well fitted to Langmuir isotherm model. The maximum adsorption capacities of manganoxide mineral for lead and cadmium ions were calculated from the Langmuir isotherm and were 98 and 6.8 mg/g, respectively. Thermodynamic parameters such as the change of Gibbs free energy, enthalpy and entropy of adsorption were also calculated and it was found that the lead and cadmium uptake reactions by manganoxide mineral were endothermic and spontaneous in nature. Therefore, manganoxide mineral can be used as adsorbents for lead and cadmium ions removal processes as an alternative natural mineral among the others.

关键词： lead cadmium manganoxide minerals adsorption kinetics adsorption isotherm metal adsorption

Vascular complications of pancreatitis

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World Journal of Clinical Cases 2022年第22期10卷 7665-7673页

作者： m Ammar Kalas monica Leon Luis omar Chavez Eduardo Canalizo salim Surani Department of medicine Texas Tech University Health CenterEl PasoTX 79905United States Department of General Surgery Centro Medico ABCCiudad de Mexico 01120Mexico Department of medicine Texas A&M UniversityBryanTX 77807United States

more than 200000 hospital admissions happen per year for acute pancreatitis and more than 50000 for chronic pancreatitis in the United States of *** pancreatitis accounts for 20%-30%of the ***-quarter of the patients with pancreatitis develop vascular complications,which carries a high *** mini-review will address these complications that can help primary care physicians and hospitalists in managing their patients effectively.

关键词： Acute pancreatitis Vascular complications Gastrointestinal bleeding Pseudoaneurysm Hemosuccus pancreaticus Pancreas

Effectiveness of Deep Learning models for Brain Tumor Classification and Segmentation

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Computers, materials & Continua 2023年第7期76卷 711-729页

作者： muhammad Irfan Ahmad Shaf Tariq Ali Umar Farooq Saifur Rahman salim Nasar Faraj mursal mohammed Jalalah Samar m.Alqhtani omar AlShorman Electrical Engineering Department College of EngineeringNajran UniversityNajran61441Saudi Arabia Department of Computer Science COMSATS University IslamabadSahiwal CampusSahiwal57000Pakistan Department of Information Systems College of Computer Science and Information SystemsNajran UniversityNajran61441Saudi Arabia College of Engineering Najran UniversityNajran61441Saudi Arabia

A brain tumor is a mass or growth of abnormal cells in the *** children and adults,brain tumor is considered one of the leading causes of *** are several types of brain tumors,including benign(non-cancerous)and malignant(cancerous)*** brain tumors as early as possible is essential,as this can improve the chances of successful treatment and *** this problem,we bring forth a hybrid intelligent deep learning technique that uses several pre-trained models(Resnet50,Vgg16,Vgg19,U-Net)and their integration for computer-aided detection and localization systems in brain *** pre-trained and integrated deep learning models have been used on the publicly available dataset from The Cancer Genome *** dataset consists of 120 *** pre-trained models have been used to classify tumor or no tumor images,while integrated models are applied to segment the tumor region *** have evaluated their performance in terms of loss,accuracy,intersection over union,Jaccard distance,dice coefficient,and dice coefficient *** pre-trained models,the U-Net model achieves higher performance than other models by obtaining 95%*** contrast,U-Net with ResNet-50 out-performs all other models from integrated pre-trained models and correctly classified and segmented the tumor region.

关键词： Brain tumor deep learning ensemble detection healthcare

Critical assessment of R410A alternatives for mini-split air conditioners in the Egyptian market

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Energy and Built Environment 2024年第3期5卷 426-445页

作者： omar m.Zaki omar Abdelaziz mechanical Power Engineering Department Faculty of EngineeringCairo UniversityGiza 12613Egypt Department of mechanical Engineering The American University in CairoAUC AvenueNew Cairo 11835Egypt

In this study,the potential implementation of three different low-GWP refrigerants(R32,R452B,and R454B)as replacements for R410A was *** study was performed using a simulation tool developed by the authors called RACHP-Lab,which is a vapor compression system simulation tool developed based on physics-based simulation for typical mini-split air *** simulation study was carried out and validated using experimental performance data of 10 different air conditioning units available in the Egyptian *** units included fixed-speed or variable-speed compressors and operated in cooling or heating ***-in replace-ment with the new refrigerants was carried *** R32,the capacity increased between 4.9%and 13%for cooling cases,and 6.3%and 12.4%for heating ***,COP did not improve in all *** R452B and R454B with direct replacement,the capacity nearly remained the same,with an increase of COP between 1.6%and 8.0%.Soft optimization was also conducted on cooling cases where compressor suction superheat,condenser subcooling,and compressor volumetric speed were optimized to maximize COP while maintaining the original capacity of R410A.R32 showed an improvement of COP over R410A between 4.6%and 15.5%,while for R452B and R454B between 2.2%and 13.2%.

关键词： Air conditioner Heat pump Alternative refrigerants Vapor compression cycle modeling

Applications of synchrophasor technologies in power systems

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Journal of modern Power Systems and Clean Energy 2019年第2期7卷 211-226页

作者： muhammad Usama USmAN m. omar FARUQUE Department of Electrical and Computer Engineering Center for Advanced Power Systems Florida State University

Synchrophasors are time-synchronized electrical measurements that represent both the magnitude and phase angle of the electrical sinusoids. Synchrophasors are measured by fast time-stamped devices called phasor measurement units(PmUs) to constitute the basis of realtime monitoring and control actions in the electric *** to its enhanced situational awareness capabilities,many applications of PmUs are presented in the literature in the past decades. This paper presents a comprehensive summary of synchrophasor technology, its architecture,optimal placement techniques and its applications in electric power transmission and distribution systems. These applications include wide-area situational awareness and monitoring, state estimation, fault location and protective relaying, islanding detection etc. This review also covers some of the existing challenges in its implementation and its potential applications.

关键词： Phasor measurement unit(PmU) Supervisory control and data acquisition(SCADA) Synchrophasor technology(ST) Power system

Unified power quality conditioner based on a three-level NPC inverter using fuzzy control techniques for all voltage disturbances compensation

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Frontiers in Energy 2014年第2期8卷 221-239页

作者： salim CHENNAI m-T BENCHOUIA Electrical Engineering Department Birine Nuclear Research Center Ain-Oussera W. Djelfa 17200 Algeria L.G.E.B Laboratories Electrical Engineering Department Biskra University Biskra 07000 Algeria

This paper presents a novel and efficient control scheme for unified power quality conditioner （UPQC） based on three-level neutral point clamped （NPC） inverter using fuzzy logic techniques. The proposed UPQC is capable of mitigating source current harmonics and compensate all voltage disturbances such as voltage sags, swells, unbalances and harmonics. It is designed by the integration of series and shunt active filters （AFs） sharing a common DC bus capacitor. The DC voltage is maintained constant using proportional integral voltage controller. The synchronous reference frame （SRF） theory is used to get the reference signals for shunt active power filters （APFs） and the power reactive theory （p-q theory） for series APFs. The shunt and series APF reference signals derived from the control algorithm and sensed signals are injected in two controllers to generate switching signals. To improve the UPQC capability, fuzzy logic techniques are introduced to control the series APF. The performances of the proposed UPQC system are evaluated in terms of power factor correction, mitigation of voltage or current harmonics and all other voltage disturbances compensation using matlab-Simulink software and SimPowerSystem toolbox. The simulation results illustrate the performance of the proposed UPQC at the common connection point of the nonlinear load to improve the power energy quality.

关键词： three-level neutral point clamped (NPC) inverter unified power quality conditioner (UPQC) current

Pulse Laser Deposition of HfO_(2)Nanoporous-Like Structure,Physical Properties for Device Fabrication

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Journal of Renewable materials 2022年第11期10卷 2819-2834页

作者： Shams B.Ali Sarmad Fawzi Hamza Alhasan Evan T.salim Forat H.Alsultany omar S.Dahham Laser and Optoelectronic Engineering Department University of TechnologyBaghdadIraq Applied Science Department University of TechnologyBaghdadIraq Al-mustaqbal University College Department of Medical PhysicsHillahIraq Center of Excellence Geopolymer and Green Technology Faculty of Engineering TechnologyUniversiti Malaysia PerlisPerlisMalaysia Department of Civil Engineering College of EngineeringCihan University-ErbilKurdistan RegionIraq

The pulsed laser deposition(PLD)technology was used to effectively create conductive nano and micro hafnium oxide with great purity and transparency for(HfO_(2))*** many optoelectronics devices and their applications,the presence of a high dielectric substance like a nano HfO2,between the metal contacts and the substrates was *** used the Pulsed Laser Deposition method to fabricate an Al/HfO_(2)/p-Si Schottky barrier diode where the nanostructured HfO2 films as an intermediate layer and varied substrate *** optical result reveals a high degree of transparency(93%).The optical bandgap of deposited HfO2 films was observed to vary between 4.9 and 5.3 eV,with a value of roughly 5.3 eV at the optimal preparation *** morphology of the surface shows a high homogeneous nano structure with the average values of the roughness about(0.3 nm).With regard to substrate temperature,the produced factor ideality for fabricated diode was determined to be lowering and the associated values of the barrier height rose based on *** regard to substrate temperature,the produced factor ideality for fabricated diode was determined to be lowering and the associated values of the barrier height rose based on I-V *** diode manufactured at 600℃,in particular,had a higher ideality factor value(n=3.2).

关键词： Pulse laser deposition nano films optoelectronics HfO_(2) optical device

Simple operated multipurpose temperature control cryostat

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 793-796页

作者： ABBAS T.A. omar m.S. Department of Physics College of Science University of SalahaddinArbilIraqi KurdistanIraq

A suitable simple optical cryostat for optical, magneto-optical, electrical and thermo-electrical measurements was designed. It is suitable for use in a magnetic pool gap as narrow as less than 1 cm. Throughout a long period of time, the heat diffusion process of the cryostat can be easily operated at slow increase in sample temperature in a range 1.25 K/min at 200 K that will be reduced gradually to 0.66 K at room temperature. Liquid nitrogen was used to cool down the temperature. During the operation, the change in the measured energy gap of a semiconductor sample and other physical parameters resulting from the change of temperature can be corrected through the temperature coefficient of that parameter at the corresponding temperature. The cryostat was successfully used for all experiments mentioned above to measure the properties of a single crystal of GaP (Gallium Phosphate) semiconductor.

关键词： Optical cryostat Electrical cryostat magneto-optical cryostat