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Ho_2(Co,Si)_(17)化合物的结构与磁晶各向异性

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物理学报 2000年第2期49卷 355-360页

作者：胡社军特古斯魏兴钊张雷曾德长刘正义 f.r.deboer K.H.J.Buschow 华南理工大学 The University of Amsterdam Amsterdam1018XE The Netherlands 内蒙古师范大学呼和浩特010022

用三弧Czochralski法和真空电弧熔炼法制备了Ho2Co17-xSix化合物.通过X射线衍射和磁性测量手段研究了化合物的结构与内禀磁性.重点讨论了磁晶各向异性和自旋重取向转变.实验结果表明,Ho2Co17为Th2Ni17型六角结构,在05≤x≤3的化合物均为... 详细信息

用三弧Czochralski法和真空电弧熔炼法制备了Ho2Co17-xSix化合物.通过X射线衍射和磁性测量手段研究了化合物的结构与内禀磁性.重点讨论了磁晶各向异性和自旋重取向转变.实验结果表明,Ho2Co17为Th2Ni17型六角结构,在05≤x≤3的化合物均为Th2Zn17型菱方结构,能够获得单相2∶17型化合物的最大Si含量是x=3.在x≤2的浓度范围,化合物的易磁化方向垂直于c轴.随Si含量增加,化合物的居里温度和Co原子平均磁矩单调减少.根据Ho2Co17-xSix化合物的居里温度和自旋重取向温度,获得了磁相图.根据热磁曲线,确定了温度补偿点.

关键词： Ho2Co17-xSix化合物结构磁晶各向异性内禀磁

rCo_(10)Mo_2(r=Y,Ho)化合物的磁性研究

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物理学报 1999年第S1期48卷 87-92页

作者：尹晓英唐宁沈宇平阳东王建立杨伏明吴光恒 f.r.deboer 中国科学院物理研究所 VanderWaalsZeemanInstituteUnive

利用ＳＱＵＩＤ磁强计和脉冲强磁场设备对ＲＣｏ１０Ｍｏ２（Ｒ＝Ｙ，Ｈｏ）化合物的磁性进行了研究．单个晶格模型和双子晶格模型被分别用于解释取向样品的磁化过程，稀土次晶格和过渡金属次晶格的各向异性以及它们之间的相互作... 详细信息

利用ＳＱＵＩＤ磁强计和脉冲强磁场设备对ＲＣｏ１０Ｍｏ２（Ｒ＝Ｙ，Ｈｏ）化合物的磁性进行了研究．单个晶格模型和双子晶格模型被分别用于解释取向样品的磁化过程，稀土次晶格和过渡金属次晶格的各向异性以及它们之间的相互作用由此得到了较好的描述．

关键词：饱和磁化强度磁化曲线化合物外加磁场过渡金属分子场系数粉末样品中国科学院稀土磁矩

Y_2(Co,Si)_(17)化合物的结构与磁晶各向异性

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稀土 2000年第4期21卷 24-29页

作者：胡社军刘正义魏兴钊曾德长 f.r.deboer K.H.J.Buschow 广东工业大学广东广州510643 华南理工大学广东广州510641 UniversityofAmsterdam University of Amsterdam

采用真空电弧熔炼法制备了 Y2 Co17- x Six化合物。用 X-射线衍射和磁性测量方法 ,研究了化合物的晶体结构和内禀磁性。实验结果表明 ,随 Si原子浓度增加 ,Y2 Co17- x Six化合物的居里温度和饱和磁化强度急剧下降。本文重点讨论了 Si原... 详细信息

采用真空电弧熔炼法制备了 Y2 Co17- x Six化合物。用 X-射线衍射和磁性测量方法 ,研究了化合物的晶体结构和内禀磁性。实验结果表明 ,随 Si原子浓度增加 ,Y2 Co17- x Six化合物的居里温度和饱和磁化强度急剧下降。本文重点讨论了 Si原子在 Co次晶格的四个不同晶位择优占位与 Co次晶格磁晶各向异性从易面转变为易轴的演化关系 ,其中 1 8h晶位对 Co次晶格各向异性负贡献起重要作用。

关键词：稀土永磁材料择优占位磁晶各向异性结构

Gd_2(Co,Si)_(17)化合物的结构与磁晶各向异性

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材料科学与工艺 2000年第1期8卷 47-51页

作者：胡社军魏兴钊曾德长刘正义 f.r.deboer K.H.J.Buschow 广东工业大学阿姆斯特丹大学华南理工大学

采用真空电弧熔炼法制备了Gd2 Co17-xSix 化合物 .通过X -射线衍射和磁性测量手段 ,研究了化合物的晶体结构和内禀磁性 .首次在Gd2 Co17-xSix(x >0 )化合物中观察到自旋重取向转变 ,获得了Gd2 Co17-xSix 的磁相图 .重点讨论了Si原子在C... 详细信息

采用真空电弧熔炼法制备了Gd2 Co17-xSix 化合物 .通过X -射线衍射和磁性测量手段 ,研究了化合物的晶体结构和内禀磁性 .首次在Gd2 Co17-xSix(x >0 )化合物中观察到自旋重取向转变 ,获得了Gd2 Co17-xSix 的磁相图 .重点讨论了Si原子在Co次晶格的四个不同晶位择优占位与Co次晶格磁晶各向异性从易面转变为易轴的演化关系 ,其中 1 8h晶位对Co次晶格各向异性负贡献起重要作用 .

关键词：永磁材料晶体结构磁晶各向异性磁合金

熔体快淬纳米晶Nd_8 fe_(77) Co_5 Cu_1 Nb_3 B_6带材

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上海钢研 2001年第3期 52-53页

作者： H.Chiriac M.Marinescu K.H.J.Buschow f.r.deboer E.Bruck 李殿魁罗马尼亚国家技术物理研究开发研究院 Van der Weals-Zeeman研究所荷兰

本文研究了Nd_8fe_(77)Co_5Cu_1Nb_3B_6熔体自旋法带材与热磁测量相关的结晶行为。只是在超过700℃的退火温度下,才获得一个稳定的两相组织。而且,当微晶小到足以引起重要的交互作用时,样品揭示一个交互弹性行为。

关键词：熔体自旋法带材纳米晶两相系统亚稳相交互弹性行为永磁材料

Inflow and outflow permeability tests in a very soft clay under low stresses

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Journal of rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： J.W.S.Vargas f.A.B.Danziger f.r.Lopes T.Lunne federal University of rio de Janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the BAT probe at SarapuíII soft clay test site are presented.A description of the BAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for SarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test Soft clay BAT probe Inflow and outflow tests

Nonlinear corrections for the nuclear gluon distribution in eA processes

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Chinese Physics C 2024年第3期48卷 52-64页

作者： G.r.Boroun B.rezaei f.Abdi Department of Physics Razi UniversityKermanshah 67149Iran.

An analytical study with respect to the nonlinear corrections for the nuclear gluon distribution function in the next-to-leading order approximation at small x is *** consider the nonlinear corrections to the nuclear gluon distribution functions at low values of x and Q^(2) using the parametrization f_(2)(x,Q^(2))and the nuclear modification factors obtained from the Khanpour-Soleymaninia-Atashbar-Spiesberger-Guzey *** CT18 gluon distribution is used for the baseline proton gluon density at Q^(2)_(0)=*** discuss the behavior of the gluon densities in the next-to-leading order and the next-to-next-to-leading order approximations at the initial scale Q^(2)_(0),as well as the modifications due to the nonlinear *** find that the QCD nonlinear corrections are more significant for the next-to-leading order accuracy than the next-to-next-to-leading order for light and heavy *** results of the nonlinear GLr-MQ evolution equation are similar to those obtained with the rausch-Guzey-Klasen gluon upward and downward evolutions within the *** magnitude of the gluon distribution with the nonlinear corrections increases with a decrease in x and an increase in atomic number A.

关键词： gluon distribution nonlinear corrections light and heavy nuclei low x physics

SnrK1a1, a new player in the sucrose-Opaque2 network during endosperm filling

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Molecular Plant 2024年第8期17卷 1172-1174页

作者： Kelly Mayrink Balmant Marcio f.r.resende Jr. Horticultural Sciences Department University of FloridaGainesvilleFLUSA

Maize(Zea mays)endosperm is an important food source for humans and *** addition,it is considered an excellent model for research on seed development because of its relatively large size for both embryo and endosperm compared to those of other crop species,such as rice(Oryza sativa)and wheat(Triticum aestivum).After double fertilization,early maize endosperm development includes three stages:(i)a multinucleate coenocyte stage;(i)a cellularization stage,in which the cellular endosperm is formed;and(ii)a stage of differentiation into distinct *** early differentiation,four major cell types with specific functions differentiate within the endosperm:starchy endosperm,aleurone layer,basal endosperm transfer layer(BETL),and embryo surrounding *** subaleurone,conducting zone,basal intermediate zone,and endosperm adjacent to scutellum arise in late differentiation(Sabelli and Larkins 2009).After the main cell types are established,maize endosperm undergoes intensive cell proliferation,which marks the transition to the endosperm-filling *** the endosperm-flling stage,the maternal sucrose products are transported to seeds through the BETL region,where they will act as the main carbon substrate for storage products such as starch and proteins(Chen et al.,2023).In fact,the endosperm of maize seeds accounts for approximately 90%of the total grain weight,serving as an important nutrient reservoir(flint-Garcia et al.,2009).

关键词： endosperm reservoir flint

Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： f.Animah C.Keles W.r.reed E.Sarver Department of Mining and Minerals Engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： respirable dust Dust control SEM–EDX Scrubber Canopy air curtain Silica