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Transition from oceanic subduction to continental collision:insights from volcanogenic-sedimentary rocks of the Tannuola terrane(northern Central Asian Orogenic Belt)

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Geoscience Frontiers 2024年第4期15卷 41-60页

作者： e.V.Vetrov N.i.Vetrova V.S.Sobolev institute of Geology and Mineralogy SB RAS Koptyuga ave.3NovosibirskRussia

Magmatism associated with oceanic subduction plays a dominant role in crustal growth during the earth's *** Tannuola terrane,situated in the northern Central Asian Orogenic Belt(CAOB),is a key area to understanding oceanic subduction and initial collision processes in the northern *** order to investigate the switch from subduction to collision settings,detailed field mapping,zircon SHRiMP U-Pb geochronological and whole-rock geochemical studies of volcanogenic-sedimentary rocks from the Tannuola terrane were carried *** U-Pb ages indicate multi-stage volcanism lasted at least 30 Ma from~540 to~510 Ma,that can be divided into three events:the late ediacaran(before~540 Ma),the early Cambrian(~520 Ma)and the middle Cambrian(~510 Ma).These ages are inter-preted to the initial,main and final stages of oceanic subduction during the late Proterozoic-early *** the late ediacaran,tholeiitic basalts with highεNd(t)values(from+7.4 to+8.5)were *** forming by the 10%-30%partial melting of spinel-garnet mantle source during slab *** the early Cambrian,transitional from tholeiitic to calc-alkaline basaltic rocks withεNd(t)value(+5.6)and coeval intermediate-felsic volcanic rocks with similarεNd(t)values(+5.9 and+6.5)*** early Cambrian basaltic rocks are interpreted to be derived by 10%-30%partial melt-ing of a depleted mantle source metasomatized by slab-derived fluids released from the subducting ocea-nic *** middle Cambrian calcalkaline basaltic rocks withεNd(t)value of+6.2 might be emplaced as a result of low(5%-10%)degree partial melting of a metasomatized mantle followed by fractional crys-tallization of clinopyroxene and *** intermediate-felsic volcanic rocks withεNd(t)values from+6.0 to+6.8 were formed through fractionation of the juvenile Neoproterozoic *** middle Cambrian volcanism is interpreted to be triggered by the slab break-off during the transition to a collisional se

关键词： island-arc magmatism ediacaran Cambrian zircon U-Pb dating Nd isotopes Central asian orogenic belt

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effect of Firing Temperature on the electromagnetic Properties of electronic Transformer Cores Developed by Using Nanosized Mn–Zn Ferrite Powders

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Acta Metallurgica Sinica(english Letters) 2015年第2期28卷 159-163页

作者： hassan Waqas Ammad Hussain Qureshi Muhammad Shahzad Materials Division Directorate of Technology PINSTECH

Current investigation deals with the effect of grain growth process as a function of sintering temperature on the electromagnetic properties （initial permeability, impedance, and gain） of Mn-Zn ferrite （MZF） cores （toroids）. By employing auto combustion process, nanosized [（20 ± 5） nm] MZF powders were synthesized and toroid shape cores were obtained after subsequent calcination and firing （sintering） process. it was observed that the submicron structure （0.5 μm） achieved in the ferrite core sintered at 1,000 ℃ was gradually transformed into micron size grains by increasing the firing temperature i.e., 1,100, 1,200, and 1,350 ℃. The results reveal that MZF core sintered at low temperature （1,000 ℃） showed high impedance, low initial permeability, and narrow working frequency range i.e., 3-15 MHz. However, the improvement in initial permeability, sintered density, and operational frequency range （100 kHz-17 MHz） was observed at high temperature （1,350 ℃） firing in the inert environment. This synthesized MZF core is more suitable for miniaturized switch mode power supply applications.

关键词： Mn-Zn ferrites Nanosized powders impedance Sintering

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environmental exposure as a risk-modifying factor in liver diseases:Knowns and unknowns

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Acta Pharmaceutica Sinica B 2021年第12期11卷 3768-3778页

作者： Juliane i.Beier Gavin e.Arteel Department of Medicine Division of GastroenterologyHepatology and NutritionUniversity of PittsburghPittsburghPA 15213USA Pittsburgh Liver Research Center and University of Pittsburgh PittsburghPA 15213USA Department of environmental and Occupational Health University of PittsburghPA 15213USA

Liver diseases are considered to predominantly possess an inherited or xenobiotic ***,inheritance drives the ability to appropriately adapt to environmental stressors,and disease is the culmination of a maladaptive *** "pure" genetic and "pure" xenobiotic liver diseases are modified by each other and other factors,identified or *** purpose of this review is to highlight the knowledgebase of environmental exposure as a potential risk modifying agent for the development of liver disease by other *** exercise is not to argue that all liver diseases have an environmental component,but to challenge the assumption that the current state of our knowledge is sufficient in all cases to conclusively dismiss this as a *** review also discusses key new tools and approaches that will likely be critical to address this question in the *** together,identifying the key gaps in our understanding is critical for the field to move forward,or at the very least to "know what we don't know."

关键词： Hepatic injury exposomics Liver disease Drug-induced liver injury Alcoholic liver disease Non-alcoholic liver disease inherited liver disease Autoimmune liver disease

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impact of the association between elevated oestradiol and low testosterone levels on erectile dysfunction severity

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Asian Journal of Andrology 2013年第4期15卷 492-496,I0007-I0008页

作者： Ahmed i e1-Sakka Department of Urology Suez Canal University 41111 Ismailia Egypt and AI-Noor Specialist Hospital Makkah PO Box 6251 Saudi Arabia

Our aim was to assess the impact of the association between elevated oestradiol （e2） and low testosterone （T） levels on erectile dysfunction （eD） severity. A total of 614 male patients with eD and a normal or low T level in association with normal or elevated e2 levels were enrolled. Patients underwent routine laboratory investigations in addition to measurements of total T, total e2, follicle-stimulating hormone （FSH）, luteinizing hormone （LH） and prolactin. We compared the responses to the erectile function domain, Q3 （achieving erection） and Q4 （maintaining erection） of the international index for erectile Function （iieF） score in patients with the following： normal T and e2 levels; low T level; low T level and elevated e2 level; and elevated e2 level. Of the patients included, 449 （73.1%） had normal T and e2 levels, 110 （17.9%） had a low T level, 36 （5.9%） had a low T level and an elevated e2 level, and 19 （3.1%） had an elevated e2 level. increased eD severity was significantly associated with low T levels, elevated e2 levels, and both a low T level and an elevated e2 level. Additionally, the mean values of the eF-domain, Q3 and Q4 were significantly lower in patients with both a low T level and an elevated e2 level compared to patients with any condition alone. in conclusion, a low T level had the primary effect on erectile function; however, a concomitantly elevated e2 level had an additive impairment effect.

关键词： erectile dysfunction (eD) hypogonadism testosterone oestradiol

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electrical Relaxation in Mixed Alkali Bi_2O_3-K_2O-Li_2O-Fe_2O_3 Glasses

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Journal of Materials Science & Technology 2006年第5期22卷 701-707页

作者： e.e.Shaisha Sh.F.el-Desouki i.Shaltout A.A.Bahgat Department of physics Faculty of science Al-Azhar UniversityNasr CityCairo 11884Egypt

A new glass system （Bi2O3）50（Fe2O3）10（Li2O）x（K2O）40-x, where x changes in steps of 5 mole fraction between 0 and 40, was selected to study the electrical relaxation and the mixed alkali effect （MAe） phenomena. Measurements of ac conductivity σac, dielectric permittivity ε′ and loss factor tanδ in the frequency range of 0.12～10^2 kHz and in the temperature range of 300～650 K were carried out. The temperature dependence of the ac conductivity shows a slow increasing rate at low temperature and high frequency and a rapid increase at high temperature and low frequency. At constant temperature, the ac conductivity is found to be proportional to ω^8, where s is the frequency exponent, which is less than 1. Analysis of the conductivity data and the frequency exponent shows that the overlapping large polaron tunnelling （OLPT） model of ions is the most favorable mechanism for the ac conduction in the present glass system. The ac response, the dc conductivity and dielectric relaxation have the same activation energy and they originate from the same basic transport mechanism. The results of the dielectric permittivity show no maximum peak in the temperature and frequency range studied. This absence of maximum peak is an indication of non-ferroelectric behavior of all the studied samples. The MAe has been detected in the ac conductivity, which is the same as the classical MAe in the dc conductivity. The electrical parameters such as dielectric permittivity ε′ and real dielectric modulus M′ show a typical minimum deviation from linearity by about two orders of magnitude. The loss factor tanδ and the imaginary dielectric modulus M″ are insignificantly dependent on composition even at the same transition temperature Tg.

关键词： Dielectric permittivity Dielectric modulus Loss factor Conduction mechanism MAe (mixed alkali effect)

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The radial evolution of earthward BBFs during substorm

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Science China earth Sciences 2010年第10期53卷 1542-1551页

作者： ReMe H DANDOURAS i LUCeK e DUNLOP M Centre d'etude Spatiale des Rayonnements Blackett Laboratory Imperial College London Rutherford Appleton Laboratory

We here study the occurrence rate,probability function of velocity and duration of earthward bursty bulk flows(BBFs) in the inner Plasma Sheet(iPS,β>0.5) using the data of Cluster in 2001 and *** occurrence rate of earthward BBFs increases with distance from the earth up to ?19 Re,which is in agreement with the previous observations of the radial evolution of *** 54% of earthward BBFs in expansion phase have a velocity larger than 600 km/s,whereas only 38% of earthward BBFs in growth and recovery phases have a velocity larger than 600 km/*** average velocity of earthward BBFs in expansion phase is 732 km/s,larger than those in growth phase(631 km/s) and recovery phase(617 km/s).The durations of earthward BBFs decrease with the decrease of downtail distance from earth due to the braking of earthward *** duration of earthward BBFs in expansion phase is larger than that in growth and recovery *** average durations in growth,expansion,and recovery phases are respectively 49.3,71.5,and 47.6 ***,the ratios of transports of energy of earthward BBFs in growth,expansion,and recovery phases can be estimated to be 0.51:1:***,the earthward BBFs in the expansion phase have the largest capability of the transport of energy and can produce the largest braking effects,such as inertial currents and auroral activities.

关键词： substorm growth expansion recovery duration energy transport

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Landau quantization effects on damping Kawahara solitons in electron–positron–ion plasma in rotating ionized medium

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Communications in Theoretical Physics 2024年第10期76卷 141-150页

作者： e i el-Awady S Hussain N Akhtar Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Theoretical Physics Division(TPD) PINSTECHP.O.Nilore 45650IslamabadPakistan

For the dynamics of three-dimensional electron–positron–ion plasmas,a fluid quantum hydrodynamic model is proposed by considering Landau quantization effects in dense ***–neutral collisions in the presence of the Coriolis force are also *** application of the reductive perturbation technique produces a wave evolution equation represented by a damped Korteweg–de Vries *** equation,however,is insufficient for describing waves in our system at very low dispersion *** a result,we considered the highest-order perturbation,which resulted in the damped Kawahara *** effects of the magnetic field,Landau quantization,the ratio of positron density to electron density,the ratio of positron density to ion density,and the direction cosine on linear dispersion laws as well as soliton and conoidal solutions of the damped Kawahara equation are *** understanding from this research can contribute to the broader field of astrophysics and aid in the interpretation of observational data from white dwarfs.

关键词： Kawahara equation solitary and cnoidal waves quantum plasma magnetoplasmas Landau quantization Coriolis force

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effects of Crossed electric and Magnetic Fields on Shallow Donor impurity Binding energy in a Parabolic Quantum Well

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Chinese Physics Letters 2004年第12期21卷 2500-2503页

作者： e.Kasapoglu H.Sari i.Soekmen DepartmentofPhysics CumhuriyetUniversity58140SivasTurkey DepartmentofPhysics DokuzEylülUniversityIzmirTurkey

We have calculated variationally the ground state binding energy of a hydrogenic donor impurity in a parabolic quantum well in the presence of crossed electric and magnetic fields. These homogeneous crossed fields are such that the magnetic field is parallel to the heterostructure layers and the electric field is applied perpendicular to the magnetic field. The dependence of the donor impurity binding energy to the well width and the strength of the electric and magnetic fields are discussed. We hope that the obtained results will provide important improvements in device applications, especially for a suitable choice of both fields in the narrow well widths.

关键词： Condensed matter: electrical magnetic and optical Semiconductors Surfaces interfaces and thin films Nanoscale science and low-D systems

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effect of Hydrostatic Pressure on interband Transitions in Coupled Quantum Wires

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Chinese Physics Letters 2007年第4期24卷 1058-1061页

作者： e. Kasapoglu M. Günes i Sokmen Department of Physics Cumhuriyet University 58140 Sivas Turkey Department of Physics Dokuz Eylül University 35160 izmir Turkey

We calculate the exciton binding energy and interband optical absorption in a rectangular coupled quantum wire under the hydrostatic pressure in the effective-mass approximation, using the variational approach. it is found that the interband optical absorption strongly depend on the hydrostatic pressure and the coupling parameter, and that the magnitude of the absorption coefficient for the HH1-e1 transition in the coupled quantum wire is larger than that of the single quantum wire.

关键词： APPLieD eLeCTRiC-FieLD SHALLOW DONOR iMPURiTieS WeLL WiReS BiNDiNG-eNeRGieS OPTiCAL-ABSORPTiON MAGNeTiC-FieLD GAAS TeMPeRATURe DePeNDeNCe THReSHOLD

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Full-Annulus Simulation of the Surge inception in a Transonic Centrifugal Compressor

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Journal of Thermal Science 2015年第5期24卷 442-451页

作者： i.Trébinjac e.Benichou N.Buffaz Laboratoire de Mécanique des Fluides et d’Acoustique UMR CNRS 5509 Ecole Centrale de Lyon UCBLyon I INSA 36 av. Guy de Collongue 69134 Ecully Cedex France Turbomeca groupe Safran 64511 Bordes France

Full annulus simulations of the flow which develops in a transonic centrifugal compressor are performed at two stable operating points （peak efficiency and near surge） and during the path to surge. At stable conditions, the flow field properties are analyzed by comparisons with experimental data and numerical simulations using a phase lagged approach previously carried out. Regarding the stage overall performance, an excellent agreement is obtained between the numerical results （both with time lagged approach and full-annulus calculation） and the ex- periments. From the full-annnlus simulations, the change in flow pattern from peak efficiency to surge is found to be perfectly similar to that obtained from the simulations using the time lagged approach. in particular, pro- vided that the operating point is stable, the flow proves to be chorochronic. The full-annulus simulations were continued after a unique small change in the throttle law applied at the exit of the numerical domain. The mass flow, pressure ratio and efficiency then significantly drop all the more the time progresses. The simulation becomes unstable and the surge inception well underway. The path to surge is found to be due to the enlargement of the boundary layer separation on the suction side of the diffuser vanes in accordance with the conclusions drawn from the chorochronic simulations and experiments. But as the time progresses, the flow loses its chorochronic character. Stall cells rotating at around 7% of the rotor speed develop and lead to surge in around 5 revolutions.

关键词： centrifugal compressor surge transonic rotating stall full-annulus simulation URANS

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