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Structural,spectroscopic,and dielectric characterizations of Mn-doped 0.67BiFeO_(3)-0.33BatiO_(3)multiferroic ceramics

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Journal of Advanced Ceramics 2013年第3期2卷 252-259页

作者： Qiming HANG Wenke ZHOU Xinhua ZHU Jianmin ZHU Zhiguo LIU talaat al-kassab National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringNanjing UniversityNanjing 210093China King Abdullah University of Science&technology(KAUSt) Physical Sci.and Eng.Thuwal 23955-6900Kingdom of Saudi Arabia

0.67BiFeO_(3)-0.33BatiO_(3)multiferroic ceramics doped with x mol%MnO_(2)(x=2-10)were synthesized by solid-state *** formation of a perovskite phase with rhombohedral symmetry was confirmed by X-ray diffraction(XRD).the average grain sizes were reduced from 0.80mm to 0.50mm as increasing the Mn-doped *** crystalline nature of the grains was revealed by high-resolution transmission electron microscopy(HRtEM)images and electron diffraction *** nano-sized ferroelectric domains with an average size of 9 nm randomly distributed in the ceramic samples were revealed by tEM *** domain lamellae(71°ferroelectric domains)with an average width of 5 nm were also *** modes were examined by Raman spectra,where only four Raman peaks at 272 cm^(-1)(E-4 mode),496 cm^(-1)(A_(1)-4 mode),639 cm^(-1),and 1338 cm^(-1)were *** blue shifts in the E-4 and A_(1)-4 Raman mode frequencies were interpreted by a spring oscillator *** dieletric constants of the present ceramics as a function of the Mn-doped levels exhibited a V-typed *** were in the range of 350-700 measured at 10^(3)Hz,and the corresponding dielectric losses were in range of 0.43-0.96,approaching to 0.09 at 10^(6)Hz.

关键词： multiferroic ceramics dielectric properties Raman spectra microstructure

Genes and proteins expressed at different life cycle stages in the model protist Euplotes vannus revealed by both transcriptomic and proteomic approaches

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Science China Life Sciences 2025年第1期 232-248页

作者： Yaohan Jiang Xiao Chen Chundi Wang Liping Lyu Saleh A.al-Farraj Naomi A.Stover Feng Gao Key Laboratory of Evolution & Marine Biodiversity (Ministry of Education) and Institute of Evolution & Marine Biodiversity Ocean University of China Marine College Shandong University Zoology Department College of ScienceKing Saud University Department of Biology Bradley University Laboratory for Marine Biology and Biotechnology Qingdao Marine Science and Technology Center

Sexual reproduction first appeared in unicellular protists and has continued to be an essential biological process in almost all *** protists, which contain both germline and somatic genomes within a single cell, have evolved a special form of sexual reproduction called conjugation that involves mitosis, meiosis, fertilization, nuclear differentiation, genome rearrangement, and the development of unique cellular structures. the molecular basis and mechanisms of conjugation vary dramatically among ciliates, and many details of the process and its regulation are still largely unknown. In order to better comprehend these processes and mechanisms from an evolutionary perspective, this study provides the first comprehensive overview of the transcriptome and proteome profiles during the entire life cycle of the newly-established marine model ciliate Euplotes vannus. transcriptome analyses from 14 life cycle stages(three vegetative stages and 11 sexual stages) revealed over 26,000 genes that are specifically expressed at different stages, many of which are related to DNA replication,transcription, translation, mitosis, meiosis, nuclear differentiation, and/or genome rearrangement. Quantitative proteomic analyses identified 338 proteins with homologs associated with conjugation and/or somatic nuclear development in other ciliates, including dicer-like proteins, Hsp90 proteins, RNA polymerase Ⅱ and transcription elongation factors, ribosomal-associated proteins, and ubiquitin-related proteins. Four of these homologs belong to the PIWI family, each with different expression patterns identified and confirmed by Rt-qPCR,which may function in small RNA-mediated genome rearrangement. Proteins involved in the nonhomologous end-joining pathway are induced early during meiosis and accumulate in the developing new somatic nucleus, where more than 80% of the germline sequences are eliminated from the somatic genome. A number of new candidate genes and proteins likely t

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Multi-segmented nanowires for vortex magnetic domain wall racetrack memory

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Chinese Physics B 2023年第12期32卷 582-588页

作者： M al Bahri M al Hinaai t al Harthy Department of Basic Sciences A'Sharqiyah UniversityPost Box 42PC 400IbraOman

A vortex domain wall's(VW) magnetic racetrack memory's high performance depends on VW structural stability,high speed, low power consumption and high storage density. In this study, these critical parameters were investigated in magnetic multi-segmented nanowires using micromagnetic simulation. thus, an offset magnetic nanowire with a junction at the center was proposed for this purpose. this junction was implemented by shifting one portion of the magnetic nanowire horizontally in the x-direction(l) and vertically(d) in the y-direction. the VW structure became stable by manipulating magnetic properties, such as magnetic saturation(M_(4)) and magnetic anisotropy energy(K_(u)). In this case, increasing the values of M_(4) ≥ 800 kA/m keeps the VW structure stable during its dynamics and pinning and depinning in offset nanowires,which contributes to maintenance of the storage memory's lifetime for a longer period. It was also found that the VW moved with a speed of 500 m/s, which is desirable for VW racetrack memory devices. Moreover, it was revealed that the VW velocity could be controlled by adjusting the offset area dimensions(l and d), which helps to drive the VW by using low current densities and reducing the thermal-magnetic spin fluctuations. Further, the depinning current density of the VW(J_(d)) over the offset area increases as d increases and l decreases. In addition, magnetic properties, such as the M_(4) and K_(u),can affect the depinning process of the VW through the offset area. For high storage density, magnetic nanowires(multisegmented) with four junctions were designed. In total, six states were found with high VW stability, which means three bits per cell. Herein, we observed that the depinning current density(J_(d)) for moving the VW from one state to another was highly influenced by the offset area geometry(l and d) and the material's magnetic properties, such as the M_(4) and K_(u).

关键词： micromagnetic simulation vortex domain wall racetrack memory multi-segmented magnetic nanowire spin transfer torque

temperature effect on the corrosion and passivation characterization of Ni_(82.3)Cr_7Fe_3Si_(4.5)B_(3.2) alloy in acidic media

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 205-214页

作者： Khadijah M.Emran Sanaa t.Arab Aisha M.al-turkustani Hamad A.al-turaif Chemistry Department Faculty of Science Taibah University Department of Chemistry Faculty of Sciences Al-Faisaliah King Abdulaziz University Department of Chemical and Materials Engineering King Abdulaziz University

the effects of temperature on corrosion and the electrochemical behavior of Ni82.3Cr7Fe3Si4.5B3.2 glassy alloy in HC1,H2SO4,and H3PO4 acids were studied using AC and DC *** data reveal that the susceptibility to localized corrosion increases with increasing *** polarization curves reveal that the bulk glassy alloy is spontaneously passivated at all the investigated temperature in H2SO4 and H3PO4 solutions.A localized corrosion effect in HCl solution is clearly *** apparent activation energies in the regions of tafel,active,and passive,as well as the enthalpies and entropies of the dissolution process were determined and *** high apparent activation energy（Ea） value for H3PO4 solution in tafel region is explained by the low aggressivity of PO4^3- ions.

关键词： nickel alloys corrosion temperature effect acidic environment passivation polarization

Peptides-based vaccine against SARS-nCoV-2 antigenic fragmented synthetic epitopes recognized by t cell and β-cell initiation of specific antibodies tofightthe infection

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Bio-Design and Manufacturing 2021年第3期4卷 490-505页

作者： Zainularifeen Abduljaleel Faisal A.al-allaf Syed A.Aziz Department of Medical Genetics Faculty of MedicineUmm Al-Qura UniversityP.O.Box715Mecca21955Kingdom of Saudi Arabia Science and technology Unit UmmAl-Qura UniversityP.O.Box 715Mecca21955Kingdom of SaudiArabia the Regional Laboratory Molecular Diagnostics UnitDepartment of Molecular BiologyMinistry of Health(MOH)P.O.Box 6251MeccaKingdom of SaudiArabia Department of Pathology and Lab Medicine University of Ottawa451Smyth RoadOttawaONK1H8M5Canada

the World Health Organization has declared the rapidly spreading coronavirus to be a global *** FDA is yet to approve a vaccine for human novel ***,we developed a peptide-based vaccine and used high-throughput screening by molecular dynamics simulation to identify t-cell-and p-cell-recognized epitopes for producing specific antibod-ies against *** construct~12 P'antigenic epitope peptides to develop a more effective vaccine and identify specific *** epitope peptides selectively presented the best antigen presentation scores for both human pMHC class I and II alleles to develop a strong binding *** antigens identified of SARS-nCoV-2 different proteins by each attached specific~1-7 L linker adaptor were used to construct a broad single peripheral peptide *** is expected to be highly antigenic with a minimum allergic *** a result of these exciting outcomes,expressing a vaccine using the intimated peptide was highly promising and positive to be highly proposed as epitope-based peptide vaccine of specific antibody against SARS-nCoV-2 by initiating t cells and β-*** in vitro study for the proposed peptide-based vaccine *** *** clinical trials are required to check the efficacy of this vaccine.

关键词： COVID-19 SARS-nCoV-2 Peptide-based vaccine Cell-penetrating peptides Lipid membrane Vaccine efficacy

transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN t.ASGHAR Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

this paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. the influence of magnetic fields is also inspected in terms of their physical characteristics. to depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).the effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368

Nonlinear time-Frequency Distributions of Spectrum Energy Operator in Large Vocabulary Mandarin Speaker Independent Speech Recognition System

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tsinghua Science and technology 2003年第6期8卷 667-671页

作者： FadhilH.t.al-dulaimy 王作英 Department of Electronic Engineering Tsinghua University

this work demonstrates the use of the nonlinear time-frequency distribution (NLtFD) of a discrete time energy operator (DtEO) based on amplitude modulation-frequency modulation demodulation techniques as a feature in speech recognition. the duration distribution based hidden Markov module in a speaker independent large vocabulary mandarin speech recognition system was reconstructed from the feature vectors in the front-end detection stage. the goal was to improve the performance of the existing system by combining new features to the baseline feature vector. this paper also deals with errors associated with using a pre-emphasis filter in the front end processing of the present scheme, which causes an increase in the noise energy at high frequencies above 4 kHz and in some cases degrades the recognition accuracy. the experimental results show that eliminating the pre-emphasis filters from the pre-processing stage and using NLtFD with compensated DtEO combined with Mel frequency cepstrum components give a 21.95% reduction in the relative error rate compared to the conventional technique with 25 candidates used in the test.

关键词： large vocabulary speech recognition duration distribution based hidden Markov module robust feature energy operator

Peripheral Nonlinear time Spectrum Features algorithm for Large Vocabulary Mandarin Automatic Speech Recognition

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tsinghua Science and technology 2005年第2期10卷 174-182页

作者： Fadhil H.t.al-dulaimy 王作英 Department of Electronic Engineering Tsinghua University Beijing 100084 China

this work describes an improved feature extractor algorithm to extract the peripheral features of point x(ti,fj) using a nonlinear algorithm to compute the nonlinear time spectrum (NL-tS) pattern. the algo- rithm observes n×n neighborhoods of the point in all directions, and then incorporates the peripheral fea- tures using the Mel frequency cepstrum components (MFCCs)-based feature extractor of the tsinghua elec- tronic engineering speech processing (tHEESP) for Mandarin automatic speech recognition (MASR) sys- tem as replacements of the dynamic features with different feature combinations. In this algorithm, the or- thogonal bases are extracted directly from the speech data using discrite cosime transformation (DCt) with 3×3 blocks on an NL-tS pattern as the peripheral features. the new primal bases are then selected and simplified in the form of the ?dp- operator in the time direction and the ?dp- operator in the frequency di- t f rection. the algorithm has 23.29% improvements of the relative error rate in comparison with the standard MFCC feature-set and the dynamic features in tests using tHEESP with the duration distribution-based hid- den Markov model (DDBHMM) based on MASR system.

关键词： large vocabulary speech recognition Mandarin automatic speech recognition (MASR) dura- tion distribution-based hidden Markov model (DDBHMM) feature identification

Pressure and Discharge-Voltage Dependence of Self-Sustaining Pulses in Air-Glow Discharge

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Chinese Physics Letters 2012年第5期29卷 181-184页

作者： A.A.Azooz Y.A.al-Jawaady Z.t.ali Department of Physics College of ScienceMosul UniversityMosulIraq

the details of formation of micro discharges in air-glow discharge plasma are experimentally *** number of micro discharges formed per second is strongly related to both pressure and discharge *** number tends to show reflections of the Patchen curve as far as its pressure dependence is *** dischargevoltage dependence indicates that the transition from normal to abnormal glow discharge is not a sudden one,but has its roots during the normal glow stage and is initiated by the micro discharges which can be regarded as the early stage of abnormal glow.

关键词： details initiated roots