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Plasma Science and Technology 2019年第6期21卷 58-62页

作者： n AHmAD A A ABID Y al-HADEETHI m n S QURESHI Saqib REHmAn Department of Engineering and Applied Physics University of Science and Technology of China Hefei 230026 People's Republic of China CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary ScienceUniversity of Science and Technology of China Hefei 230026 People's Republic of China Department of Physics Faculty of Sciences King Abdulaziz Unniversity Jeddah 21589 Saudi Arabia Department of Physics GC University Lahore 54000 Pakistan Department of Chemical Physics University of Science and Technology of China Hefei 230026People's Republic of China

Charging mechanism of dust particles has been considered as a growing research area in dusty plasma physics because of its exciting *** this paper,we consider a low-temperature non-equilibrium multispecies plasma model,which consists of Vasyliunas-Caims (VC) distributed electrons,negative/positive streaming ions,and negatively-charged dust grains to explain the charging mechanism of dust *** main theme of this work is to derive expressions of currents for negatively-charged dust grains (considering an equilibrium state position) in the plasma environment comprised of electrons and positive/negative streaming ions using the VC distribution *** proposed model shows that the dust grain surface potential is significantly affected by different plasma parameters such as the negative ion streaming velocity (Sn),positive ion streaming velocity (Si),spectral indices of VC distribution,negative ion charging state (Zn),positive ion charging state (Zi),and negative ion number density (ρ).

关键词： dust grain surface potential vasyliunas-cairns power law velocity distribution function multi species plasma

Insights from an academic endeavor into central nervous system drug discovery

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neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An m.Voets Tim Vanmierlo Rudy Schreiber BIOmED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University mS Center(UmSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in modern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(mazzucato,2013).

关键词： academic approval consequences

Approximation of Rainfall Erosivity Factors in north Jordan

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Pedosphere 2010年第6期20卷 711-717页

作者： n.I.ELTAIF m.A.GHARAIBEH F.al-ZAITAWI m.n.alHAmAD Department of natural Resources and Environment Faculty of AgricultureJordan University of Science and Technology

Despite being in arid and semi-arid areas,erosion is largely a result of infrequent but heavy rainfall events; therefore,rainfall erosivity data can be used as an indicator of potential erosion *** purpose of this study was to investigate the spatial distribution of annual rainfall erosivity in north Jordan.A simplified procedure was used to correlate erosivity factor R values in both the universal soil loss equation (USLE) and the revised universal soil loss equation (RUSLE) with annual rainfall amount or modified Fournier index (F mod ).Pluviometric data recorded at 18 weather stations covering north Jordan were used to predict R *** annual values of erosivity ranged between 86-779 mJ mm ha ?1 h ?1 year ?1 .The northwest regions of Jordan showed the highest annual erosivity values,while the northeastern regions showed the lowest annual erosivity values.

关键词： erosion Fournier index iso-erodent map universal soil loss equation

Impact of grazing on soil, vegetation and ewe production performances in a semi-arid rangeland

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Journal of mountain Science 2018年第4期15卷 685-694页

作者： muhammad ISLAm Abdul RAZZAQ shamim GUL Sarfraz AHmAD Taj mUHAmmAD Sawsan HASSAn Barbara RISCHKOWSKY m.n.m.IBRAHIm mounir LOUHAICHI International Center for Agricultural Research in Dry Areas (ICARDA) South Asia Islamabad Pakistan Animal Sciences Division Pakistan Agricultural Research Council Islamabad Pakistan Botany Department University of Balochistan Quetta Pakistan Department of natural Resource Sciences McGill University QC Canada natural Resources Division Pakistan Agricultural Research Council Islamabad Pakistan Forest & Wildlife Department Quetta Balochistan Pakistan International Center for Agricultural Research in Dry Areas (ICARDA) Amman Jordan International Center for Agricultural Research in Dry Areas (ICARDA) SSA ILRI campus Addis Ababa Ethiopia International Livestock Research Institute (ILRI) Pakistan

Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOm), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(nDF), acid detergent fiber(ADF), calcium(Ca), magnesium(mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg measure software. From June to november in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(Pn grasses than shrubs. In both years, the controlled grazing increased the weight gain of ewes about two folds compared to the uncontrolled *** results

关键词： Grazing exclosure Soil organic matter Vegetation cover Vegmeasure

Enhancing Bandwidth Utilization of IP Telephony Over IPv6 networks

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Computer Systems Science & Engineering 2023年第2期44卷 1039-1049页

作者： Hani al-mimi Yousef alrabanah mosleh m.Abualhaj Sumaya n.al-khatib al-Zaytooanh University of Jordan Faculty of Science and Information TechnologyDepartment of CybersecurityAmman11733Jordan al-Ahliyya Amman University Faculty of Information TechnologyDepartment of Software EngineeringAmman19328Jordan al-Ahliyya Amman University Faculty of Information TechnologyDepartment of Networks and Information SecurityAmman19328Jordan

The demand for the telecommunication services,such as IP telephony,has increased dramatically during the COVID-19 pandemic *** tele-phony should be enhanced to provide the expected *** of the issues that should be investigated in IP telephony is bandwidth *** telephony pro-duces very small speech samples attached to a large packet *** header of the IP telephony consumes a considerable share of the bandwidth allotted to the IP *** wastes the network's bandwidth and inﬂuences the IP telephony *** paper proposes a mechanism(called Smallerize)that reduces the bandwidth consumed by both the speech sample and the *** is achieved by assembling numerous IP telephony packets in one header and use the header'sﬁelds to carry the speech *** metrics have been used to measure the achievement Smallerize *** number of calls has been increased by 245.1%compared to the typical *** bandwidth saving has also reached 68%with the G.28 ***,Smallerize is a possible mechanism to enhance bandwidth utilization of the IP telephony.

关键词： –IP telephony codec bandwidth utilization IPv6

Convective Heat and mass Transfer in magneto Jeffrey Fluid Flow on a Rotating Cone with Heat Source and Chemical Reaction

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Communications in Theoretical Physics 2018年第11期69卷 534-540页

作者： S.Saleem m.m.al-Qarni S.nadeem n.Sandeep Department of mathematics College of Sciences King Khalid University Department of mathematics Quaid-e-Azam University Department of mathematics Central University of Karnataka

The present paper addresses the megnetohydrodynamic Jeffrey fluid flow with heat and mass transfer on an infinitely rotating upright cone. Inquiry is carried out with heat source/sink and chemical reaction ***, constant thermal and concentration flux situations are imposed. Optimal homotopy analysis method (OHAm) is employed to achieve series solutions of the concerned differential equations. Important results of the flow phenomena are explored and deliberated by means of graphs and numerical tables. It is perceived that thermal boundary layer thickness possess contrast variations for the heat source and heat sink, respectively. The chemical reaction enhances the heat transfer rate but decline the mass transfer rate. moreover, the precision of the existing findings is verified by associating them with the previously available work.

关键词： magnetohydrodynamics Jeffrey fluid rotational flow heat generation/absorption chemical reaction

FInITE GROUPS WHOSE mInImal SUBGROUPS ARE WEAKLY H-SUBGROUPS

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Acta mathematica Scientia 2012年第6期32卷 2295-2301页

作者： m.m.al-mosa al-Shomrani m.Ramadan A.A.Heliel Department of mathematics Faculty of Science 80203King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of mathematics Beni-Suef UniversityFaculty of Science 62511Beni-SuefEgypt

Let G be a finite group. A subgroup H of G is called an H-subgroup in G if nG（H）∩ H^g ≤ H for all g C G. A subgroup H of G is called a weakly H-subgroup in G if there exists a normal subgroup K of G such that G = HK and H n K is an H-subgroup in G. In this paper, we investigate the structure of the finite group G under the assumption that every subgroup of G of prime order or of order 4 is a weakly H-subgroup in G. Our results improve and generalize several recent results in the literature.

关键词： c-normal subgroup H-subgroup p-nilpotent group supersolvable group generalized Fitting subgroupi saturated formation

Skew Information for a Single Cooper Pair Box Interacting with a Single Cavity Field

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Communications in Theoretical Physics 2013年第6期59卷 769-772页

作者： n.metwally A.al-mannai m.Abdel-Aty mathematics Department College of Science University of Bahrain mathematics Department Faculty of Science Aswan University of Aswan Scientific Publishing Center University of Bahrain mathematics Department Faculty of Science Sohag University of Sohag

The dynamics of the skew information (SI) is investigated for a single Cooper Pair Box (CPB) interacting with a single cavity field. By suitably choosing the system parameters and precisely controlling the dynamics, novel connection is found between the SI and entanglement generation. It is shown that SI can be increased and reach its maximum value either by increasing the number of photons inside the cavity or considering the far off-resonant *** number of oscillations of SI is increased by decreasing this ratio between the Josephson junction capacity and the gate capacity. This leads to significant improvement of the travelling time between the maximum and minimum values.

关键词： entanglement skew information Cooper Pair Box

Dust particle surface potential in an argonhelium plasma using the(r,q)-distribution function

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Communications in Theoretical Physics 2024年第9期76卷 141-148页

作者： Bahaaudin m Raffah A A Abid Abdullah Khan Amin Esmaeili Yas al-Hadeethi m n S Qureshi Department of Physics Faculty of SciencesKing Abdulaziz UniversityJeddah 21589Saudi Arabia Lithography in Devices Fabrication and Development Research Group Deanship of Scientific ResearchKing Abdulaziz UniversityJeddah 21589Saudi Arabia Joint Laboratory of Plasma Application Technology Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei230026China CAS Key Laboratory of Geospace Environment University of Science and Technology of ChinaHefei230026China Department of Physics Zhejiang Normal UniversityJinhua321005China Department of Physics Graduate School of ScienceTokyo Metropolitan UniversityMinami-Osawa 1-1Hachioji City192-0397Japan Department of Physics GC UniversityLahore 54000Pakistan

In this paper,the dust particle surface potential for argon-helium plasma is evaluated analytically and numerically in the context of negatively charged dust particles by employing a power-law(r,q)-distribution *** studies have reported the argon-helium plasma and conducted a brief theoretical and experimental *** deepen our understanding further,this study aims to analyze the argon-helium plasma comprehensively using the same pattern but with the(r,q)-distribution *** this purpose,the current balance equations are derived for electron,helium and argon ions,when these charge species attain the quasineutrality *** numerically examined the currents of plasma species for a broad range of effective distribution function parameters r and *** is revealed that the surface potential of dust particles is significantly affected by the parameters r and q,helium ion-to-electron temperature ratio,argon ion-to-electron temperature ratio,and helium ion to argon ion number density *** incorporating the multi-ion(argon-helium)species,the significance of low-temperature nonmaxwellian dusty(complex)plasma is briefly examined.

关键词： dusty plasma dust charge potential plasma physics helium argon plasma r q distribution function non-maxwellian distribution

Levitation and lateral forces between a point magnetic dipole and a superconducting sphere

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Chinese Physics B 2016年第5期25卷 453-456页

作者： H m al-Khateeb m K alqadi F Y alzoubi B albiss m K Hasan (Qaseer) n Y Ayoub Department of Physics Jordan University of Science and Technology School of Basic Sciences and Humanities German Jordanian University

The dipole–dipole interaction model is employed to investigate the angular dependence of the levitation and lateral forces acting on a small magnet in an anti-symmetric magnet/superconducting sphere system. Breaking the symmetry of the system enables us to study the lateral force which is important in the stability of the magnet above a superconducting sphere in the meissner state. Under the assumption that the lateral displacement of the magnet is small compared to the physical dimensions of our proposed system, analytical expressions are obtained for the levitation and lateral forces as a function of the geometrical parameters of the superconductor as well as the height, the lateral displacement, and the orientation of the magnetic m.m.nt of the magnet. The dependence of the levitation force on the height of the levitating magnet is similar to that in the symmetric magnet/superconducting sphere system within the range of proposed lateral displacements. It is found that the levitation force is linearly dependent on the lateral displacement whereas the lateral force is independent of this displacement. A sinusoidal variation of both forces as a function of the polar and azimuthal angles specifying the orientation of the magnetic m.m.nt is observed. The relationship between the stability and the orientation of the magnetic m.m.nt is discussed for different orientations.

关键词： lateral and levitation forces meissner effect dipole–dipole interaction model superconductor