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Photometric and Spectroscopic Study of Ten Low mass Ratio Contact Binary Systems:Orbital Stability,O'Connell Effect and Infrared Calcium Line Filling

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Research in Astronomy and Astrophysics 2024年第8期24卷 212-222页

作者： Surjit S.Wadhwa Adam Popowicz Raúl michel Petar Kostić Oliver Vince Nick F.H.Tothill ain Y.De Horta miroslav D.Filipović School of Science Western Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia Department of Electronics Electrical Engineering and MicroelectronicsSilesian University of TechnologyAkademicka 1644120 GliwicePoland Instituto de Astronomía UNAM.A.P.87722800 EnsenadaBCMéxico Astronomical Observatory Volgina 711060 BelgradeSerbia

Low mass ratio contact binary systems are more likely to have unstable orbits and potentially *** addition,such systems exhibit characteristics such as starspots and high energy emissions(UV)suggestive of chromospheric and magnetic *** curve modeling of ten contact binary systems is *** were found to be of extreme low mass ratio ranging from 0.122 to 0.24 and three were found to be potentially unstable and possible merger *** of the infrared calcium absorption lines is a marker of increased chromospheric *** use the available Large Sky Area multi-Object Fiber Spectroscopic Telescope spectra along with matched standard spectra(broadened for rotation)to measure the excess filling of the central core depression flux of the two main infrared calcium absorption linesλ8542 andλ*** find that all reported contact binaries have excess filling of the core flux in the infrared calcium *** of the systems reported were also observed by the Galaxy Evolution Explorer mission and we find that all three have features of excess ultraviolet emissions further adding evidence for increased chromospheric activity in low mass ratio contact *** of both orbital stability and absorption line filling is dependent on the determination of geometric and absolute parameters from light curve *** an insignificant number of contact binary light curves exhibit the O’Connell effect,usually attributed to *** discuss the inclusion of starspots in light curve solutions and how they influence the geometric and absolute parameters.

关键词： (stars)binaries eclipsing-techniques photometric-stars chromospheres

Online plasma diagnostics of a laser-produced plasma

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Plasma Science and Technology 2017年第1期19卷 85-89页

作者： Kai GAO Nasr A m HAFZ Song LI mohammad mIRZAIE Guangyu LI Quratul ain Key Laboratory for Laser and Plasmas （mOE） and Depatment of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 People＇s Republic of Chin Collaborative Innovation Center of IFSA Shanghai Jiao Tong University Shanghai 200240 People＇s Republic of China

In this study,we report a laser interferometry experiment for the online-diagnosing of a laserproduced *** laser pulses generating the plasma are ultra-fast（30 femtoseconds）,ultraintense（tens of Terawatt） and are focused on a helium gas jet to generate relativistic electron beams via the laser wakefield acceleration（LWFA） mechanism.A probe laser beam（λ=800 nm） which is split-off the main beam is used to cross the plasma at the time of arrival of the main pulse,allowing online plasma density *** interferometer setup is based on the No marski method in which we used a Fresnel bi-prism where the probe beam interferes with itself after crossing the plasma medium.A high-dynamic range CCD camera is used to record the interference *** upon the Abel inversion technique,we obtained a 3D density distribution of the plasma density.

关键词： plasma diagnostics probe beam interferometry abel inversion

Viscoelastic potential flow instability theory of Rivlin-Ericksen electrified fluids of cylindrical interface

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Journal of Ocean Engineering and Science 2024年第4期9卷 311-316页

作者： D.m.mostafa Department of mathematics College of ScienceQassim UniversityPO Box 6644Buraidah 51452Saudi Arabia Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

A linear electrohydrodynamic Kelvin-Helmholtz instability of the interface between two viscoelastic Rivlin-Ericksen fluids enclosed by two concentric horizontal cylinders has been studied via the viscoelastic potential flow *** dispersion equation of complex coefficients for asymmetric disturbance has been obtained by using normal mode *** stability criteria are analyzed theoretically and illustrated *** imaginary part of growth rate is plotted versus the wave *** influences of dynamic viscoelastic,uniform velocities,Reynolds number,electric field,dynamic viscosity,density fluids ratio,dielectric constant ratio and inner fluid fraction on the stability of the system are *** study finds its significance in Ocean pipelines to transfer oil or gas such as Eastern Siberia-Pacific Ocean oil pipeline.

关键词： Rivlin-Ericksen fluid Cylindrical flow Viscoelastic potential flow Electrohydrodynamics stability

Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 547-561页

作者： mokhtar Ellali mokhtar Bouazza Ashraf m.Zenkour Smart structures Laboratory University of Ain TemouchentAin Temouchent 46000Algeria Department of Civil Engineering University Tahri Mohamed of BecharBechar 08000Algeria Department of mathematics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Laboratory of materials and Hydrology(LmH) University of Sidi Bel AbbesSidi Bel Abbes 22000Algeria Department of mathematics Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33516Egypt

Several studies on functionally graded materials(FGms)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in *** work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of *** model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine *** FGm plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse *** utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials.

关键词： FGm plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function

Large magnetocaloric effect and magnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.Sajieddine A.Elouafi A.El Hachmi S.El Ouahbi R.moubah Laboratory of Energy and materials Engineering (LGEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial management (EmINES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on matter and Instrumentation (LRmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔSm),was determined by em ploying the thermodynam ic maxwell's *** μ0H=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔSmand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration magnetic properties magnetocaloric effect Rare earths X-ray photoelectron spectroscopy

Canted antiferromagnetic and optical properties of nanostructures of mn_2O_3 prepared by hydrothermal synthesis

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Chinese Physics B 2012年第11期21卷 441-447页

作者： Qurat-ul-ain Javed Wang Feng-Ping m.Yasir Rafique Arbab mohammad toufiq m.Zubair Iqbal Department of Physics School of Mathematics and PhysicsUniversity of Science and Technology Beijing

We have reported new magnetic and optical properties of mn2O3 nanostructures. The nanostructures have been synthesized by the hydrothermal method combined with the adjustment of pH values in the reaction system. The particular characteristics of the nanostructures have been analyzed by employing X-Ray diffraction （XRD）, scanning electron microscopy （SEm）, energy dispersive X-ray （EDX） analysis, transmission electron microscopy （TEm）, high resolution transmission electron microscopy （HRTEm）, Raman spectroscopy （RS）, UV-visible spectroscopy, and the vibrating sample magnetometer （VSm）. Structural investigation manifests that the synthesized mn2O3 nanostructures are orthorhombic crystal. magnetic investigation indicates that the mn2O3 nanostructures are antiferromagnetic and the antiferromagnetic transition temperature is at TN = 83 K. Furthermore, the mn2O3 nanostructures possess canted antiferromagnetic order below the Neel temperature due to spin frustration, resulting in hysteresis with large coercivity （1580 Oe） and remnant magnetization （1.52 emu/g）. The UV-visible spectrophotometry was used to determine the transmittance behaviour of mn203 nanostructures. A direct optical band gap of 1.2 eV was acquired by using the Davis-mott model. The UV-visible spectrum indicates that the absorption is prominent in the visible region, and transparency is more than 80% in the UV region.

关键词： mn2O3 orthorhombic nanocrystals UV transparency canted antiferromagnetic property

Hematology and Some Biochemical Parameters of Wild Rodents in Pistachio Gardens of Kerman Province, Southeast Iran

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应用与环境生物学报 2011年第6期17卷 907-909页

作者： mADJDZADEH Sm ABBASNEJAD m TAKALLOOZADEH hm mammalian Biodiversity Research Unit Department of Biology Faculty of Sciences Shahid Bahonar University of Kerman 76169-14111 Kerman Iran Department of Plant Pathology Faculty of Agriculture Shahid Bahonar University of Kerman 76169-14111 Kerman Iran

Wild rodents were collected using live snap traps in pistachio gardens of Kerman Province, Southeast Iran from 2007 to 2009, then some physiological parameters of them were measured. The samples were identified as follow: Nesokia indica, meriones persicus, meriones lybicus and Tatera indica. Blood samples were obtained from the heart, then the blood parameters (glucose, cholesterol, triglyceride, total protein, HDL, red and white blood cell number) in wild species of rodents and laboratory rat were compared. The results showed that there were no significant differences in serum glucose, triglyceride, HDL and total protein levels among different experimental groups. The concentration of cholesterol in T. indica was more than that in N. indica (P mbers of red blood cells also showed significant difference between wild garden rodent species and laboratory rat (P mbers of white blood cells showed no significant difference.

关键词： rodents hematological parameter biochemical parameter pistachio gardens Kerman Province, Iran

Robust malicious Executable Detection Using host-Based machine Learning Classifier

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Computers, materials & Continua 2024年第4期79卷 1419-1439页

作者： Khaled Soliman mohamed Sobh Ayman m.Bahaa-Eldin Department of Computer and Systems Engineering Ain Shams UniversityCairo11517Egypt Department of Computer Engineering Technology ElSewedy University of TechnologyCairo44629Egypt

The continuous development of cyberattacks is threatening digital transformation endeavors worldwide and leadsto wide losses for various organizations. These dangers have proven that signature-based approaches are insufficientto prevent emerging and polymorphic attacks. Therefore, this paper is proposing a Robust malicious ExecutableDetection (RmED) using host-based machine Learning Classifier to discover malicious Portable Executable (PE)files in hosts using Windows operating systems through collecting PE headers and applying machine learningmechanisms to detect unknown infected files. The authors have collected a novel reliable dataset containing 116,031benign files and 179,071 malware samples from diverse sources to ensure the efficiency of RmED *** most effective PE headers that can highly differentiate between benign and malware files were selected totrain the model on 15 PE features to speed up the classification process and achieve real-time detection formalicious executables. The evaluation results showed that RmED succeeded in shrinking the classification timeto 91 milliseconds for each file while reaching an accuracy of 98.42% with a false positive rate equal to 1.58. Inconclusion, this paper contributes to the field of cybersecurity by presenting a comprehensive framework thatleverages Artificial Intelligence (AI) methods to proactively detect and prevent cyber-attacks.

关键词： Portable executable malware intrusion detection cybersecurity zero-day threats host IntrusionDetection System(HIDS) machine learning Anomaly-based Intrusion Detection System(AIDS) deep learning

Growth of monodisperse nanospheres of mnFe_2O_4 with enhanced magnetic and optical properties

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Chinese Physics B 2013年第10期22卷 453-459页

作者： m.Yasir Rafique 潘礼庆 Qurat-ul-ain Javed m.Zubair Iqbal 邱红梅 m.Hassan Farooq 郭振刚 m.Tanveer College of Science and Research Institute for New Energy China Three Gorges University Department of Physics University of Science and Technology of Beijing School of material Science and Engineering University of Science and Technology of Beijing Research Center of materials Science Beijing Institute of Technology

Highly dispersive nanospheres of mnFe204 are prepared by template free hydrothermal method. The nanospheres have 47.3-nm average diameter, narrow size distribution, and good crystallinity with average crystallite size about 22 nm. The reaction temperature strongly affects the morphology, and high temperature is found to be responsible for growth of uniform nanospheres. Raman spectroscopy reveals high purity of prepared nanospheres. High saturation magnetization （78.3 emu/g）, low coercivity （45 Oe, 10e = 79.5775 ***-1）, low remanence （5.32 emu/g）, and high anisotropy constant 2.84 × 10^4 J/m3 （10 times larger than bulk） are observed at room temperatures. The nearly snperparamagnetic behavior is ~ spin due to comparable size of nanospheres with superparamagnetic critical thameter Dcr spm The high value of Keff may be due to coupling between the pinned moment in the amorphous shell and the magnetic moment in the core of the nanospheres. The nanospheres show prominent optical absorption in the visible region, and the indirect band gap is estimated to be 0.98 eV from the transmission spectrum. The prepared mn ferrite has potential applications in biomedicine and photocatalysis.

关键词： mn ferrite magnetic materials hydrothermal method superparamagnetic Raman spectroscopy