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Crystal structures, phase relationships, and magnetic phase transitions of R_5M_4 compounds (R = rare earths, M = Si, Ge)

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Chinese Physics B 2013年第9期22卷 1-28页

作者：欧阳钟文饶光辉 Wuhan National High Magnetic Field Center Huazhong University of Science and Technology School of Materials Science and Engineering Guilin University of Electronic Technology

Our recent studies of the crystal structures, phase transitions, and magnetic properties of intermetallic compounds RsM4 （R = rare earths; M = Si, Ge） are reviewed briefly. First, crystal structures, phase relationships, and magnetic prop- erties of several 5：4 compounds, including Nd5 Si4-xGex, Pr5 Si4_xGex, Gds-xLaxGe4, La5 Si4, and Gd5 Sn4, are presented. In particular, the canted spin structures as well as the magnetic phase transitions in PrsSi2Ge2 and PrsGe4 investigated by neutron powder diffractions and small-angle neutron scattering are reviewed. Second, the crystal structures and magnetic properties of the most studied compounds Gds（Si,Ge）4 are summarized. The focus is on the parent compound GdsGe4, which is an amazing material exhibiting magnetic anisotropy, angular dependent spin-flop transition, metastable magnetic response, Griffiths-like phase, thermal effect under pulsed fields, antiferromagnetic and ferromagnetic resonances, pro- nounced effects of impurities, and high-field induced magnetic transitions.

关键词： crystal structure phase relationship magnetic phase transition

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phase relationshipS IN R-Fe PSEUDOBINARY SYSTEM (R=Dy_(0.65)Tb_(0.25)Pr_(0.1))

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 109-115页

The phase relationships of R-Fe pseudobinary system(R=Dy0.65Tb0.25Pr0.1) have been determined using optical microscopy,X-ray diffraction,EPMA and DTA *** system contains one eutectic reaction and four peritectic *** four intermetallic compounds are(Dy,Tb,Pr)Fe2,(Dy,Tb,Pr)Fe3,(Dy,Tb,Pr)6Fe23 and(Dy,Tb,Pr) 2Fe17 The homogeneity regions of these compounds shift towards rare earth-rich side of the stoichiometric composition except(Dy, Tb,Pr) 2Fe17.

关键词： rare earth-iron alloy phase relationship structure

Modified Wiener Beamforming for Indoor Channel Improvement

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Modified Wiener Beamforming for Indoor Channel Improvement

1998 International Conference on Communication Technology

作者： Gao Xing Huang Ya-Ru Inner Mongolia University

ISBN: (纸本)7800908275

＜正＞The impulse response of an indoor channel varies with different environments and spatial positions of a transceiver pair as a function of the phase relationship among individual multipath components that have variety of time *** factor results in various fading especially in a chip duration of the Direct Sequence Code Division Multiple（DS-CDMA） *** solve this problem,a Modified Wiener Beamforming（MWB） has been proposed to co-phase the multipath components and then combine them by maximum ratio combining in a chip duration We derive formulas for MWB with a method to separate and estimate multipath vectors through each *** purpose is to isolate and recombine multipath components before they are added together as a phasor to produce ***,the fading of Rayleigh or Rice distributed multipath in a chip duration can be reduced to a *** results are presented by using a three-dimension ray tracing to support the proposed method.

关键词： array signal processing spread spectrum communication code division multiple access multiuser channels multipath channels Rician channels Rayleigh channels indoor radio ray tracing transient response direction-of-arrival estimation modified Wiener beamforming indoor channel improvement impulse response indoor channel spatial positions transceiver pair phase relationship multipath components time delays chip duration direct sequence code division multiple access DS-CDMA system maximum ratio combining multipath vectors Rice distributed multipath Rayleigh distributed multipath simulation results 3D ray tracing antenna array

phase Relations,Crystal Structure,and Luminescent Properties of A New Phosphate Based Phosphor

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Phase Relations,Crystal Structure,and Luminescent Properties...

中国晶体学会第六届学术年会暨会员代表大会——多晶（粉晶）衍射分会

作者： J.Zhang G.M.Cai Z.P.Jin School of Materials Science and Engineering Education Ministry Key Laboratory of Non-ferrous Materials Science and Engineering Central South University

In this work,the phase relationship of MgO-InO-PO ternary system have been systematically investigated via solid-state reactions,leading to discover a new ternary compound *** analysis based on powder x-ray diffraction data is implemented to determine the crystal structure of this *** structure-,composition-,and temperature-dependent photoluminescent properties of lanthanide-doped MgInPO phosphors are investigated by means of structural analysis,photoluminescence excitation(PLE) and emission(PL)spectrum,decay lifetime,low-temperature and high-temperature luminescence,and chromaticity coordinate.

关键词： phase relationship crystal structure phosphor photoluminescent property

Equilibrium of CaO-SiO2-FeO-P2O5 multi phase flux at 1673K with low oxygen partial pressure for dephosphorization

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Equilibrium of CaO-SiO2-FeO-P2O5 multi phase flux at 1673K w...

Ninth International Conference on Molten Slags,Fluxes and Salts(MOLTEN12)

作者： Hiroyuki MATSUURA Fumitaka TSUKIHASHI Graduate School of Frontier Sciences The University of Tokyo2778561Japan

＜正＞Dephosphorization process by using multi phase flux could significantly decrease the consumption of CaO and prevent environmental harmful fluorite ***,the equilibrium phase relationship remains unclear,which is ... 详细信息

关键词： Steelmaking multi phase flux phase relationship equilibrium dephosphorization

Warming magnitude of Indonesian Throughflow during the penultimate deglaciation (Termination Ⅱ) and its relationship with climate change in high-latitude regions

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Science Bulletin 2010年第32期55卷 3710-3718页

作者： TIAN CuiCui & TIAN Jun State Key Laboratory of Marine Geology,Tongji University,Shanghai 200092,China

The tropical oceans are important source areas for global heat and water vapor transport,and changes in tropical sea surface temperature (SST) will have important impacts on high-latitude and global climate change. It is crucial to establish the precise phase relationship between tropical and high-latitude climate variability to gain insight into the mechanisms of global climate change. Here,we present multi-proxy records across the penultimate deglaciation (Termination Ⅱ) from sediment Core SO18459,which is located in the outflow area of the Indonesian Throughflow (ITF) of the Timor Sea. These proxy records include planktonic and benthic foraminifera δ 18O,planktonic foraminifera G. ruber Mg/Ca-derived SST,and δ18Ow of sea surface water. The Mg/Ca-SST records indicate a warming of 4.1°C in the Timor Sea over Termination Ⅱ,which is in phase with decrease in planktonic and benthic δ18O. Our results suggest that at millennial timescales,climate change of the tropical oceans is synchronous with high-latitude ice volume changes. Furthermore,warming of the Timor Sea is almost simultaneous with warming of the Antarctic,suggesting a rapid heat transfer from the tropics to the Antarctic via the atmosphere and/or ocean circulations. The G. ruber δ18O and SST records of Core SO18459 show a marked YD-like event during Termination Ⅱ,which is probably caused by decrease in Australian rainfall or strengthening of the Western Pacific Warm Pool. However,a similar YD-like event is not observed in East Asian rainfall records. This discrepancy indicates that different tropical climate systems may have different responses to the same forcing,such as El Nio Southern Oscillation. A similar YD-like event is observed in the global benthic foraminiferal δ18O records during Termination Ⅱ,implying teleconnection of millennial scale climate change between the tropical regions and high latitudes.

关键词： Indonesian Throughflow Termination Ⅱ tropic sea surface temperature high-latitude phase relationship

The precise link between East Asian monsoon and Antarctic climates during the last glacial period

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地球环境学报 2011年第1期 325-326页

作者： WANG Yong-jin CHEN Shi-tao CHENG Hai Lawrence Edwards R WU Jiang-ying KONG Xing-gong College of Geography Science Nanjing Normal University Department of Geology and Geophysics University of Minnesota

The idea of bi-polar seesaw has persisted for nearly two decades,motivating intensive research of models and records to investigate phase relationship of abrupt climate changes between two hemispheres during the ice *** current dating uncertainties and geograpmcally-limited coverage of records,however,make it difficulty to reconcile model-data and anchor their exact phase relationship,leading as yet to no consensus on factors that control the abrupt climate changes through oceanic/atmospheric *** we present several extensively dated and resolution monsoon records during the last glacial period from three caves in South China,which reinforces the correlation of climatic events between Greenland temperature and East Asian monsoon on centennial-millennial time *** allocating variations of atmosphere methane trapped in bi-polar ice cores on the;Th dated chronology,we demonstrate that six millennial scale weak monsoon events inversely correlate to,within dating uncertainty,the major warm events at Antarctica between 35;0 ka *** synchroneity is further supported by one-to-one assignment of centennial-scale climate variability superimposed on the longer-term *** observation suggests synchronous changes of the subtropical monsoons and bi-polar climates on centennial-millennial scales through strong coupling of intertropical convergence zone（ITCZ） and Atlantic oceanic meridional overturning circulations（AMOC）,in support of the classic see-saw hypothesis.

关键词： speleothem China millennial-scale variability phase relationship

The Eu3+ local environment and luminous behavior based on new phosphor hosts in the MO-In2O3-P2O5(M=Mg, Ca, Sr, Ba) system

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The Eu3+ local environment and luminous behavior based on ne...

中国稀土学会2021学术年会

作者： Ge-mei Cai Jing Zhang Yi-jia Liu Rong-rong Wang Gen-xing Zhang School of Materials Science and Engineering Central South University

For exploring novel phases for optical-functional application,we have systematically investigated phase equilibrium relation of the MO-InO-PO (M=Mg,Ca,Sr,Ba) *** phase relations of these system were determined in virtue of powder X-ray diffraction (XRD),with the samples prepared by high temperature solid state *** new phosphates have been discovered and *** the polycrystalline powder,Ab initio and Rietveld full-spectrum-fitting method,the crystal structures of all new compounds were *** regard to the special layered-structure nature of some phosphates,the rare-earth Eu doped luminescence has been systematically *** effect and rule of crystal structure,composition,site-occupation and poly-ion interaction on the local environment and luminous behavior of Eu activators will be reported here,which can support a guide for developing and designing related phosphors usable for solid state display and lighting devices.

关键词： phase relationship New phosphate Crystal structure Eu doped luminous behavior Local environment