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Diverse features of magnetization curves of uniaxial crystals：A simulation study

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Chinese Physics B 2017年第1期26卷 454-465页

作者： hala A.Sobh Samy h.Aly Department of Physics Faculty of Science at Damietta Damietta University P. O. Box 89 New Damietta 34517 Egypt

We present a simulation of the magnetization curves, energy, probability, and torque landscapes of uniaxial systems with up to five anisotropy constants. The total energy used in the simulation is the sum of the anisotropy and Zeeman energies. The exchange interaction is not considered in the present work in which we treat single-domain-particle systems within a classical mechanics-based model. Diverse features of the calculated magnetization curves are highlighted for the studied systems. These diverse features are strongly dependent on the sign and magnitude of the simulation *** model is versatile enough to handle both hypothetical and real material systems, e.g. hoFe（11）Ti and Y2Co（17）.

关键词： magnetization curve saturation moments magnetic anisotropy ferromagnetic metals and alloys

Text-Independent Algorithm for Source Printer Identification Based on Ensemble Learning

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Computers, Materials & Continua 2022年第10期73卷 1417-1436页

作者： Naglaa F.El Abady Mohamed Taha hala h.Zayed Department of Computer Science Faculty of Computers and Artificial IntelligenceBenha University13518Egypt School of Information Technology and Computer Science(ITCS) Nile University12677Egypt

Because of the widespread availability of low-cost printers and scanners,document forgery has become extremely *** or signatures are used to protect important papers such as certificates,passports,and identification *** the origins of printed documents is helpful for criminal investigations and also for authenticating digital versions of a document in today’s *** printer identification(SPI)has become increasingly popular for identifying frauds in printed *** paper provides a proposed algorithm for identifying the source printer and categorizing the questioned document into one of the printer classes.A dataset of 1200 papers from 20 distinct(13)laser and(7)inkjet printers a.h.eved significant identification results.A proposed algorithm based on global features such as the histogram of Oriented Gradient(hOG)and local features such as Local Binary Pattern(LBP)descriptors has been proposed for printer *** classification,Decision Trees(DT),k-Nearest Neighbors(k-NN),Random Forests,Aggregate bootstrapping(bagging),Adaptive-boosting(boosting),Support Vector Ma.h.ne(SVM),and mixtures of these classifiers have been *** proposed algorithm can accurately classify the questioned documents into their appropriate printer *** adaptive boosting classifier attained a 96%*** proposed algorithm is compared to four recently published algorithms that used the same dataset and gives better classification accuracy.

关键词： Document forensics source printer identification(SPI) hOG LBP principal component analysis(PCA) bagging AdaBoost

Mineralogy and geochemistry of fine-grained Dahab stream sediments, Southeastern Sinai, Egypt: emphasis on the intergrowths of Fe–Ti oxides

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Acta Geochimica 2021年第6期40卷 871-894页

作者： Adel A.Surour Ahmed.M.A.El-Kammar Ebtisam h.Arafa hala M.Korany Petroleum and Mining Geology Faculty of SciencesGalala University43511 New Galala CityEgypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt

Mineralogical and geochemical characteristics of stream sediments collected from 30 stations in the Dahab-Wadi Kid area(southeastern Sinai,Egypt)are *** studied sediments contain considerable amounts of heavy minerals,including abundant Fe–Ti oxides,with up to 25.94%index figure that measures the relative abundance of heavy minerals to light *** of the sediments and nature of Fe–Ti oxide intergrowths,in addition to some non-opaque heavy minerals,indicate multiple provenances with contributions from a variety of Neoproterozoic mafic to felsic *** amounts of heavy minerals are derived from schists that belong to the so-called Wadi Kid volcanosedimentary *** to the considerable contribution of the felsic intrusions represented by within-plate granites,the sediments are enriched in REE-bearing minerals(e.g.,monazite,cerianite,La-cerianite and allanite),V-bearing thorite,zircon,and a ZrO_(2) *** majority of Fe–Ti oxides are derived from the mafic intrusions,and they show evidence of pre-,syn-and post-depositional phases of alteration and formation of *** to the geochemical signature of the bulk silt fraction,there is remarkable enrichment of LREEs with distinct negative Eu anomaly,and this supports dominance of a provenance dominated by felsic intrusions(i.e.,the A-type within-plate granite and associated pegmatites).Also,the felsic provenance is responsible for slight abnormality of ∑PU+Th content(up to~37 ppm)and few anomalous samples bear uraniferous zircon and Ce-type *** present paper sheds light on the fertility of the Dahab stream sediments in some economic minerals for possible future exploitation,not for gold only,but for potential REEbearing minerals that are needed for a wide spectrum of modern technological industries.

关键词： Dahab stream sediments Silt fraction Fe-Ti oxides Textural variations Rees enrichment

高效率BaAl_(4)Sb_(2)O_(12)∶Eu^(2+)荧光粉合成与发光性能

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发光学报 2024年第5期45卷 753-761页

作者：王凯旋周雪莲张钰王泽苏日力格哈拉木吉田启旭朝克夫内蒙古师范大学物理与电子信息学院内蒙古呼和浩特010022 内蒙古自治区功能材料物理与化学重点实验室内蒙古呼和浩特010022 内蒙古自治区新能源储能材料工程研究中心内蒙古呼和浩特010022

白光LED作为第四代照明光源已经广泛应用到人们生活的各个领域,其中荧光粉是获得高性能白光LED的关键材料之一。如何用简单的方法制备高性能的荧光粉是目前研究人员的一个挑战性工作。本文采用高温固相法,加入助熔剂h_(3)BO_(3)、Nh_(4... 详细信息

白光LED作为第四代照明光源已经广泛应用到人们生活的各个领域,其中荧光粉是获得高性能白光LED的关键材料之一。如何用简单的方法制备高性能的荧光粉是目前研究人员的一个挑战性工作。本文采用高温固相法,加入助熔剂h_(3)BO_(3)、Nh_(4)Cl、SrF_(2)、LiF和BaF_(2),成功制备了BaAl_(4)Sb_(2)O_(12)∶Eu^(2+)(BASO∶Eu^(2+))荧光粉。通过晶体结构分析、发射光谱、X射线光电子能谱(XPS)以及荧光寿命分析,表明过量的Sb_(2)O_(3)能够有效地将Eu^(3+)还原成Eu^(2+),提高Eu^(2+)在563 nm处的荧光强度约12.5倍,内量子效率(IQE)可以达到96.14%。另外,还研究了不同助熔剂对荧光粉晶体结构、荧光强度以及内量子效率的影响。本实验采用的方法简单,避免使用具有一定危险的还原性气体烧结,易于工业化应用以及降低生产成本。

关键词： BaAl_(4)Sb_(2)O_(12)∶Eu^(2+) 还原作用助熔剂白光LEDs

Relationship between vitamin D and IL-23,IL-17 and macrophage chemoattractant protein-1 as markers of fibrosis in hepatitis C virus Egyptians

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World Journal of hepatology 2012年第8期4卷 242-247页

作者： Noha M El husseiny hala M Fahmy Waleed A Mohamed hisham h Amin Internal Medicine Department Faculty of MedicineCairo UniversityCairo 11111Egypt Internal Medicine Department Faculty of MedicineCairo University Cairo 11111Egypt Department of Chemistry Cairo UniversityCairo 12534Egypt Clinical Pa.h.logy Department Faculty of Medicine AL Azhar UniversityCairo 15533Egypt

AIM: To assess vitamin D in hepatitis C patients and its relationship to interleukin (IL)-23, IL-17, and macrophage chemoattractant protein-1 (MCP-1). METhODS: The study was conducted on 50 Egyptian hepatitis C virus (hCV) genotype number IV-infected patients and 25 age- and gender-matched healthy subjects. Venous blood samples were obtained. Samples were allowed to clot and sera were separated by centrifugation and stored at -20?°C. A 25 hydroxy vitamin D assay was carried out using solid phase RIA. A 1,25 dihydroxy vitamin D assay was carried out using a commercial kit purchased from Incstar Corporation. IL-17 and -23 and MCP-1 were assayed by an enzyme immunoassay. Quantitative and qualitative polymerase chain reaction for hCV virus were done by TaqMan technology. Only hCV genotype IV-infected subjects were included in the study. The mean ± SD were determined, a t-test for comparison of means of different parameters was used. Correlation analysis was done using Pearson’s correlation. Differences among different groups were determined using the Kruskal-Wallis test. RESULTS: The mean vitamin D level in hCV patients (group?I) was 15 ± 5.2 ng/mL while in control (group II) was 39.7 ± 10.8. For active vitamin D in group?I?as 16.6 ± 4.8 ng/mL while in group II was 41.9 ± 7.9. IL-23 was 154 ± 97.8 in group?I?and 6.7 ± 2.17 in group II. IL-17 was 70.7 ± 72.5 in cases and 1.2 ± 0.4 in control. MCP-1 was 1582 ± 794.4 in group?I?and 216.1 ± 5.38 in group II. Vitamin D deficiency affected 72% of hCV-infected patients and 0% of the control group. Vitamin D insufficiency existed in 28% of hCV-infected patients and 12% of the control group. One hundred percent of the cirrhotic patients and 40% of non cirrhotic hCV-infected patients had vitamin D deficiency. IL-23, IL-17, and MCP-1 were markedly increased in hCV-infected patients in comparison to controls.A significant negative correlation between vitamin D and IL-17 and -23 and MCP-1 was detected. hCV-infected males and females

关键词： Vitamin D Macrophage chemoattractant protin-1 Liver cirrhosis Interleukin-23 Interleukin-17 Liver cirrhosis

Plus Energy Buildings:A Numerical Case Study

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Fluid Dynamics & Materials Processing 2023年第1期19卷 117-134页

作者： Abed hawila hala Alsalloum Abdelatif Merabtine Farouk Fardoun Ra.h.d Bennacer EPF School of Engineering Rosieres-Prés-TroyesFrance Faculty of Engineering Lebanese UniversityHadathLebanon Centre Scientifique et Technique du Batiment Health and Comfort DepartmentSaint-Martin-D’HèresFrance Doctoral School of Science and Technologies Lebanese UniversityHadathLebanon Faculty of Technology Department GIMLebanese UniversitySaidaLebanon LMPS Paris Saclay UniversityParisFrance

The feasibility of Plus Energy Building for a sample relevant case is *** a literature review aimed to identify key aspects of this type of buildings,a preliminary evaluation of the thermal performance of a building constructed using conventional material is presented together with a parametric analysis of the impact of typical influential *** domestic hot water(SDhW)and photovoltaic systems(PV)are considered in the *** simulations indicate that for the examined sample case(Beirut in Lebanon)the total annual energy need of conventional building is 87.1 kWh/y.m^(2).About 49%of energy savings can be a.h.eved by improving the building envelope and installing energy efficient ***,about 90%of energy savings in domestic hot water production can be a.h.eved by installing a SDhW system composed of two solar collectors connected in ***,the addition of a grid connected PV array system can significantly mitigate the energy needs of the building leading to an annual excess of energy.

关键词： Plus energy building building performance simulation parametric analysis energy-efficient design solar energy

Charge-transfer interaction of drug quinidine with quinol,picric acid and DDQ: Spectroscopic characterization and biological activity studies towards understanding the drug–receptor mechanism

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Journal of Pharmaceutical Analysis 2014年第2期4卷 81-95页

作者： hala h.Eldaroti Suad A.Gadir Moamen S.Refat Abdel Majid A.Adam Department of Chemistry Faculty of EducationAlzaeim Alazhari University Department of Chemistry Faculty of ScienceTaif University Department of Chemistry Faculty of SciencePort Said University

Investigation of charge-transfer （CT） complexes of drugs has been recognized as an important phenomenon in understanding of the drug-receptor binding mechanism. Structural, thermal, morpholo-gical and biological behavior of CT complexes formed between drug quinidine （Qui） as a donor and quinol （QL）, picric acid （PA） or dichlorodicyanobenzoquinone （DDQ） as acceptors were reported. The newly synthesized CT complexes have been spectroscopically characterized via elemental analysis;infrared （IR）, Raman, 1h NMR and electronic absorption spectroscopy; powder X-ray diffraction （PXRD）;thermogravimetric （TG） analysis and scanning electron microscopy （SEM）. It was found that the obtained complexes are nanoscale, semi-crystalline particles, thermally stable and spontaneous. The molecular composition of the obtained complexes was determined using spectrophotometric titration method and was found to be 1：1 ratios （donor：acceptor）. Finally, the biological activities of the obtained CT complexes were tested for their antibacterial activities. The results obtained herein are satisfactory for estimation of drug Qui in the pharmaceutical form

关键词： Quinidine Charge-transfer interac-tion Powder X-ray diffractionMorphology Thermal analysis

A Compact 28 Ghz Millimeter Wave Antenna for Future Wireless Communication

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Computers, Materials & Continua 2022年第7期72卷 301-314页

作者： Shahid Khan Adil Ba.h.r haider Ali Abdul Rauf Mohamed Marey hala Mostafa Ikram Syed LCOMS ASECUniversity de LorraineMetz57070France Department of Electrical and Computer Engineering Comsats University IslamabadAbbottabad Campus22060Pakistan Electrical Engineering Department Bahauddin Zakariya UniversityMultan60800Pakistan Department of Electronics Technology University of TechnologyNowshera24100Pakistan Department of Electrical Engineering National University of Sciences and TechnologyH-12Islamabad44000Pakistan Smart Systems Engineering Laboratory College of EngineeringPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Computer Software Engineering Military College of SignalsNational University of Sciences and TechnologyIslamabad44000Pakistan

This article presents a novel modified chuck wagon dinner bell shaped millimeter wave(mm-wave)antenna at 28 *** proposed design has ultra-thin Rogers 5880 substrate with relative permittivity of *** design consists of T shaped resonating elements and two open ended side *** desired 28 Ghz frequency response is a.h.eved by careful parametric modeling of the proposed *** maximum a.h.eved single element gain at the desired resonance frequency is 3.45 *** efficiency of the proposed design over the operating band is more than 88%.The impedance bandwidth a.h.eved for−10 dB reference value is nearly 2.9 *** proposed antenna is transformed into four element linear array which increases the gain up to 10.5 *** fabricated prototype is tested for the measured *** is observed that measured results closely match the simulated *** considering its simple structure and focused radiation patterns,the proposed design is well suited for IoT(Internet of Things),mmWave microwave sensing,5G and future RF(Radio Frequency)frontends.

关键词： RF front-ends mmWave partial ground plane 28 Ghz IoT 5G antenna

Serologic, endoscopic and pa.h.logic findings in pediatric celiac disease: A single center experience in a low/middle income country

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World Journal of Clinical Pediatrics 2022年第3期11卷 295-306页

作者： hala h Mansour Nabil A Mohsen Mortada.h. El-Shabrawi Somia M Awad Dalia Abd El-Kareem Department of Pediatrics Faculty of Medicine Kasr Al AinyCairo UniversityCairo 12411Egypt Department of Pa.h.logy Cairo UniversityCairo 11562Egypt

BACKGROUND Studies in Africa,Asia,and Latin America are needed to provide a comprehensive picture of the global incidence of celiac disease(CD).AIM To describe the serology,endoscopic and histological findings in typical and atypical presentations of pediatric CD at a tertiary referral hospital in an African low/middle income country(LMIC).METhODS This observational study was conducted on 199 patients with CD from 2010 to *** patients were divided into typical and atypical groups according to the presenting symptoms including 120 and 79 patients ***,upper gastrointestinal endoscopy with duodenal biopsy were performed for patients who had symptoms suggestive of *** severity of the intestinal damage was graded according to the histo-pa.h.logic Marsh-Oberhuber *** Chronic diarrhea was the main intestinal presentation in the typical *** was the most common extraintestinal symptom in both the typical and atypical ***-Oberhuber type 3b and 3c was significantly higher in the seropositive patients with a P value of 0.007.A significant correlation was observed between the histological grade of the biopsied duodenal mucosa and the clinical presentation(Phigher in the atypical group(P valuehough typical CD was observed in 120 patients in this study,the clinical variability of the condition was frequently *** only was a significant predictor for the appearance of atypical ***,CD presentations in LMIC are not different from industrialized countries.

关键词： Typical Atypical celiac disease Celiac serology Marsh-Oberhuber histopa.h.logy