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System size dependence in backward relativistic hadron production in pA and AA collisions

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Chinese Physics C 2014年第11期38卷 22-28页

作者： b.m.badawy Reactor Physics Department Nuclear Research Center Atomic Energy Authority Cairo Egypt

Abstract： In this comprehensive study the multiplicity characteristics of the backward emitted relativistic hadron （shower particle） through hadron-nucleus and nucleus-nucleus are overviewed in three dimensions. These dimensions are the projectile size, target size, and energy. To confirm the universality in this production system, wide ranges of system size and energy （Elab～2.1 A up to 200 A GeV） are used. The multiplicity characteristics of this hadron imply a limiting behavior with respect to the projectile size and energy. The target size is the main effective parameter in this production system. The exponential decay shapes is a characteristic feature of the backward shower particle multiplicity distributions. The decay constant changes with the target size to be nearly 2.02, 1.41, and 1.12 for the interactions with CNO, Era, and Agbr nuclei, respectively, irrespective of the projectile size and energy. While the backward production probability and average multiplicity are constants at different projectile sizes and energies, they can be correlated with the target size in power law relations.

关键词： backward relativistic hadron dubna energy and SPS energy multiplicity characteristics system size,nuclear limiting fragmentation

Warm Deformation microstructure of a Plain Carbon Steel

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Journal of Iron and Steel Research International 2011年第7期18卷 41-46页

作者： b Eghbali m Shaban Department of materials Engineering Sahand University of Technology

Grain refinement in a plain carbon steel under intercritical warm deformation was studied by torsion tes ring. based on the experimental results, the warm flow behaviour and microstructural evolution of ferrite were researched with particular emphasis on the effect of the strain rate in controlling the grain refinement mechanism of fer- rite. The deformed microstructures were investigated at various strain rates using optical microscopy and electron back-scattered diffraction （EbSD）. The EbSD observations indicate that an increase in the strain rate leads to the development of new fine ferrite grains with high angle boundaries. Furthermore, it shows that the annihilation of dislo- cations occurs more readily at lower strain rate. The elongated ferrite grains continuously dynamically recrystallize to form the equiaxed fine ferrite grains. Thereby, the aspect ratio of elongated grains decreases with increasing the strain rate. Furthermore, the peak stress and steady state stress of ferrite both increase with increasing strain rate. based on the study, the effect of strain rate on the development of fine ferrite grains during continuous dynamic recrystallization of ferrite was analyzed in detail.

关键词： grain refinement steel strain rate torsion testing EbSD

Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： m.b.KIRKHAm Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the moon or mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the moon and mars.

关键词： soils soil bases

meson-production experiments at COSY-Jülich

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Chinese Physics C 2010年第9期34卷 1263-1268页

作者： m.büscher Institute für Kernphysik and Jülich Center for Hadron Physics

Selected results from experiments at COSY-Jülich are presented： an attempt to measure the mass of the η meson with high precision （ANKE facility）,first steps towards the detection of rare η decays （WASA）,and s... 详细信息

关键词： meson production

Alloy design by dislocation engineering

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Journal of materials Science & Technology 2018年第3期34卷 417-420页

作者： m.X.Huang b.b.He Department of mechanical Engineering The University of Hong Kong

Ultra-high strength alloys with good ductility are ideal materials for lightweight structural application in various industries. However, improving the strength of alloys frequently results in a reduction in ductility, which is known as the strength-ductility trade-off in metallic materials. Current alloy design strategies for improving the ductility of ultra-high strength alloys mainly focus on the selection of alloy composition （atomic length scale） or manipulating ultra-fine and nano-grained microstructure （grain length scale）. The intermediate length scale between atomic and grain scales is the dislocation length scale. A new alloy design concept based on such dislocation length scale, namely dislocation engineering, is illustrated in the present work. This dislocation engineering concept has been successfully substantiated by the design and fabrication of a deformed and partitioned （D＆P） steel with a yield strength of 2,2 GPa and an uniform elongation of 16%. In this D＆P steel, high dislocation density can not only increase strength but also improve ductility. High dislocation density is mainly responsible for the improved yield strength through dislocation forest hardening, whilst the improved ductility is achieved by the glide of intensive mobile dislocations and well-controlled transformation-induced plasticity （TRIP） effect, both of which are governed by the high dislocation density resulting from warm rolling and martensitic transformation during cold rolling. In addition, the present work proposes for the first time to apply such dislocation engineering concept to the quenching and partitioning （Q＆P） steel by incorporating a warm rolling process prior to the quenching step, with an aim to improve simultaneously the strength and ductility of the Q＆P steel. It is believed that dislocation engineering provides a new promising alloy design strategy for producing novel strong and ductile alloys.

关键词： Alioy design Dislocation engineering D&P steel Q&P steel TRIP Warm rolling

FUNCTIONAL bRAIN ImAGING bASED ON EEG AND mEG

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神经解剖学杂志 2001年第B7期17卷 81-85页

作者： Thomas R. kn SCHE ANT Software bV Netherlands PhD

Introduction Electroencephalography (EEG) and magnetoencephalography (mEG) provide temporal special information on electrophysiological processes within the human brain. While the temporal information can be exactly r... 详细信息

关键词：功能性脑电成像 EEG mEG 重建

Soil: An Extreme Habitat for microorganisms?

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Pedosphere 2004年第2期14卷 137-144页

作者： m.bLTER Institute for Polar Ecology University of Kiel Wischhofstr. 1-3 Bldg. 12 D-24148 Kiel (Germany)

The question is asked whether soils can be regarded as extreme environments with respect to microorganisms. After defining some extreme environments in a general sense, special properties of extreme environments are compared to soil habitats, with special emphasis laid on time frame and localities. In relation to water availability, nutrients and other properties, such places as aggregates can show properties of extreme habitats. These features, which can act at different levels of the system from the community level down to the cellular level, are summarized as stress factors. The latter,where many switches are located leading to different strategies of survival, is described as the most important one. This raises the question of how organisms have adapted to such conditions. The soil system demands a broad spectrum of adaptations and/or adjustments for a highly variable *** soil microorganisms'adaptation can thus be seen as the highest kind of flexibility and is more useful than any other special adaptation.

关键词：土壤环境微生物营养水分

Effect of Ion Concentrations on the Characteristics of a multi-Component magnetized Plasma Sheath

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Plasma Science and Technology 2009年第6期11卷 642-646页

作者： m.m.HATAmI b.SHOKRI Laser-Plasma Research Institute of Shahid beheshti University G.C.EvinTehranIran Physical Department and Laser-Plasma Research Institute of Shahid beheshti University G.C.EvinTehranIran

A hydrodynamic approach is used to investigate a three-component magnetized plasma sheath which consists of electrons and two species of positive ions. Assuming a phase space of one-dimensional spatial coordinate system and three-dimensional velocity coordinate system, the effect of different concentrations of positive ion species on some characteristics of the plasma sheath such as the velocity and density distribution of positive ion species and the electrostatic potential of this region is investigated. The calculated results show that the increase in the density ratio of positive ion species causes a decrease in both the ion velocities and the electrostatic potential of the sheath region. Also, it is shown that in the sheath region of a magnetized plasma consisting of only one positive ion species the bumps of the net density of charged particles disappears much faster. In addition, three-dimensional velocity of each positive ion species in the sheath region is plotted for different concentrations of positive ion species.

关键词： magnetized plasma plasma and electropositive plasma sheath hydrodynamic equations multi-component sheath

Celiac disease as potential obstacle to childbearing

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Open Journal of Obstetrics and Gynecology 2014年第2期4卷 75-80页

作者： mónika Kovács mária Szenes Tihamér Horváth Gyorgy Vajda beáta Gasztonyi Gyorgy bártfai Department of Internal medicine Zala County HospitalZalaegerszegHungary Department of Obstetrics and Gynecology Zala County HospitalZalaegerszegHungary Faculty of medicine Obstetrics and Gynecology Department Albert Szent-Gyorgyi Clinical Center of University SzegedSzegedHungary

AIm: The authors have aimed at confirming or excluding gluten sensitivity in infertile couples. PATIENTS AND mETHODS: between 2004 and 2010, at our outpatient clinics of immunology, both partners of 223 couples, who had striven for having a child unsuccessfully, underwent history taking, physical examination, laboratory and immuno-serologic tests including anti-tissue-transglutaminase antibody (antitTG), as well as deep duodenal biopsy in antibody-carrying patients. RESULTS: Antibodies against tissue transglutaminase were positive in 6/223 female patients of whom the diagnosis of celiac disease was histologically confirmed in 3/223 cases (1.34%). Of the male patients 2/223 (0.9%) have proven to be carriers of the antibody;histology was pathognomonic in both of them. Curiously, one of the male patients with celiac disease has been the partner of a woman who also had celiac disease diagnosed by the authors. In the followup period, a female patient and the female member of the couple with celiac disease gave birth to healthy newborns after spontaneous conception, as the result of a strictly kept gluten-free diet, as well as occasional treatments of acetylsalicylate for antiphos-pholipid syndrome or levothyroxine for latent hypothyroidism due to autoimmune thyroiditis. CONCLUSION: The results underline that it is worth performing a screening for celiac disease in both partners of couples assessed due to the lack of success in having a child, as infertility can be ceased by an appropriate diet.

关键词： Celiac Disease Gluten-Free Diet Anti-Tissue-Transglutaminase Antibody Infertile Couples