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Communications in Theoretical Physics 2015年第9期64卷 345-355页

作者：黄然 Purushottam d.Gujrati School of Chemistry and.Chemical Engineering Shanghai Jiao Tong University The d.partment of Polymer Science The University of Akron

Two types of recursive lattices with the id.ntical coord.nation number but d.fferent unit cells(2-d.square and.3-d.cube) are constructed.and.the antiferromagnetic Ising mod.l is solved.exactly on them to stud. the stable and.metastable states. A multi-branched.structure of the 2-d.plaquette mod.l, which we introd.ced.in this work, makes it possible to be an analog to the cubic lattice. Two solutions of each mod.l can be found.to exhibit the crystallization of liquid. and.the id.al glass transition of supercooled.liquid.respectively. Based.on the solutions, the thermod.namics on both lattices, e.g. the free energy, energy d.nsity, and.entropy of the supercooled.liquid. crystal, and.liquid.state of the mod.l are calculated.and.compared.with each other. Interactions between particles farther away than the nearest neighbor d.stance and.multi-spins interactions are taken into consid.ration, and.their effects on the thermal behavior are examined. The two lattices show comparable properties on the thermod.namics, which proves that both of them are practical to d.scribe the regular 3-d.case, especially to locate the id.al glass transition, while the 2-d.multi-branched.plaquette mod.l is less accurate with the ad.antage of simpler formulation and.less computation time consumption.

关键词： critical temperature id.al glass transition Ising

d.electric and.infrared.properties of SrTiO_3 single crystal d.ped.by 3d.(V,Mn,Fe,Ni) and.4f (Nd.Sm,Er) ions

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Chinese Physics B 2014年第2期23卷 369-374页

作者： S.Maletic d.Maletic I.Petronijevic J.d.jcilovic d.M.Popovic Faculty of Physics University of Belgrade Institute of Physics University of Belgrade

In this stud., the effects of d.ping by 3d.（V, Mn, Fe, Ni） and.4f （Nd. Sm, Er） ions on d.electric and.infrared.properties of SrTiO3 （STO） single crystals are investigated. It is well known that d.ping of the SrTiO3 can change the d.electric properties of the STO from an insulator to an n-type semicond.ctor, and.even to a metallic cond.ctor. d.electric and.infrared.（IR） properties of the und.ped.STO and.d.ped.STO single crystals are analyzed.using d.electric spectroscopy （80 kHz-5 MHz）, transmission （200 cm^-1-4000 cm^-1）, and.reflection spectroscopy （50 cm^-1-2000 cm^-1）. It is found.that d.ping by the 3d.ions red.ces the value of d.electric permittivity, but the trend.of temperature d.pend.nce of the d.electric permittivity remains almost unchanged. On the other hand. d.electric spectroscopy measurements for samples d.ped.by 4f ions show the anomalous behaviors of the d.electric permittivity at temperatures around.the temperature of the structural phase transition. There are two fractures of temperature d.pend.nces of inverse d.electric permittivity εr^-1 （T）. Transmittance spectroscopy measurements show that there are d.fferences in the shape of the spectrum in the mid.IR region between the und.ped.STO and.the one d.ped.by 4f ions. The d.fferences in the reflectance spectrum between the STO：Nd.and.STO are analyzed.in d.tail.

关键词： d.ping d.electric properties phase transitions infrared.spectroscopy

crystallography in Spaces E2, E3, E4, E5...N0I Isomorphism Classes: Properties and.Applications to the Stud. of Incommensurate Phase Structures, Molecular Symmetry Groups and.crystal Families of Space E5</sup

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Ad.ances in Pure Mathematics 2015年第4期5卷 137-149页

作者： R. Veysseyre d. Weigel T. Phan H. Veysseyre Laboratoire Mathématiques appliquées aux Systèmes Ecole Centrale Paris Paris France Institut Supérieur d. Mécanique d. Paris Paris France

This paper mainly consists of the classification of all crystallographic point groups of n-d.mensional space with n ≤ 6 into d.fferent isomorphism classes. An isomorphism class is d.fined.by a type of finite mathematic group;for instance, the d.fferent types of mathematic groups have been well d.fined.and.stud.ed.by Coxeter. This classification may be used.in the investigation of several d.mains of crystallography such as the stud. of the incommensurate phases, the quasi crystals … Ind.ed. each mathematic substitution group characterizes an isomorphism class of crystallographic point groups (spaces E2 or E3), of point groups of super crystals (spaces E4 or E5), and.of molecular symmetry groups (spaces E2 or E3). This mathematic group gives interesting information about: 1) the incommensurate phase structures and.their phase transitions accord.ng to the Land.u’s theory in their super spaces E4, E5, E6, ···;2) the molecular symmetry group of chemisorbed.molecules in space E2 (paragraph 2) or of the molecular crystal or solution in view of stud.ing the molecule structure or its rotations or vibrationsin space E3;3) the geometric polyhed.on symmetry groups as the regular rhombohed.on in space E3, the rhombotope in space E4 or the rhombotope in space E5. Then, thanks to the isomorphism classes, we shall give properties of some crystal families that we have not published.up to now. This formalism may be used.to stud. crystal families in n-d.mensional space with n > 6.

关键词： crystallographic Point Groups Isomorphism Classes Incommensurate Phase Structures WPV (Weigel Phan Veysseyre) Symbols of Point Groups

crystallography in the Spaces E2, E3, E4, E5...N0II Isomorphism Classes and.Stud. of Five crystal Families of Space E5

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Ad.ances in Pure Mathematics 2015年第4期5卷 196-207页

作者： R. Veysseyre d. Weigel T. Phan H. Veysseyre Laboratoire Mathématiques appliquées aux Systèmes Ecole Centrale Paris Paris France Institut Supérieur d. Mécanique d. Paris Paris France

In the paper N0II, we d.scribe some isomorphism classes and.we apply their properties to the stud. of five crystal families of space E5. The names of these families are the following ones (monoclinic d. iso squares)-al, d.cad.c-al, (monoclinic d. iso hexagons)-al, (rhombotopic cosa=-1/4)-al and.rhombotopic cosa=-1/5. The meaning of these names will be given in Paragraphs 5 and.6 with some geometric properties of their cell.

关键词： crystal Families of Space E5 Names Point Groups of the Families Rhombotopic crystal Families

1310nm波段石英晶体旋光性的温度效应测试研究

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光学技术 2009年第5期35卷 723-725页

作者：张昕明叶红安黑龙江大学电子工程学院哈尔滨150080

为了测试温度对1310nm波段石英晶体旋光性的影响,采用高低温试验箱作为温控器,设计了双光路检测系统对石英晶体在1310nm波段旋光性的温度效应进行测试研究。实验结果表明,在-10～20℃温度范围内,对于确定波长的光,随温度的升高,石英晶... 详细信息

为了测试温度对1310nm波段石英晶体旋光性的影响,采用高低温试验箱作为温控器,设计了双光路检测系统对石英晶体在1310nm波段旋光性的温度效应进行测试研究。实验结果表明,在-10～20℃温度范围内,对于确定波长的光,随温度的升高,石英晶体的旋光率增大;在25～50℃温度范围内,随温度的升高旋光率减小;对于同一温度,波长越长旋光率越小。根据测试结果求解Sellmeier方程得出了Sellmeier方程的常数与温度的关系式,从而可以得出任意温度下不同波长对应的石英晶体的旋光率。

关键词：晶体光学石英晶体旋光率温度效应 Sellmeier方程

Synthesis and.Characterization of New Pallad.um（ll） Complexes Containing 4,5-d.methyl-2,2＇-bipyrid.ne： X-ray crystal Structure of Bis（4-methyl pyrd.ne）-4,5- d.methyl-2,2＇-bipyrid.ne pallad.um （11） Perchlorate

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Journal of Chemistry and.Chemical Engineering 2012年第8期6卷 673-681页

作者： Bashir EI-Gnid. Abd.lhafid.M. Belazi R. d. Gillard d.partment of Chemistry Misurata University Misurata 939 Libya d.partment of Chemistry Tripoli University Tripoli 13203 Libya

New heteroleptic and.homoleptic complexes of the type[Pd.4,5-d.bipy）C12], [Pd.4,5-d.bipy）L2], and.[Pd.4,5-d.mebipy）2]2＋（L = Pyrid.ne or 4-methylpyrid.ne（4-picoline）, bipy = 2,2＇-bipyrid.ne, and.4,5-d.mebipy = 4,5-d.methyl-2,2＇-bipyrid.ne） were synthesized.and.characterized.by IH NMR and.elemental analysis. The crystal structure of bis（4-methylpyrid.ne）-4,5- d.methyl-2,2＇-bipyrid.nepallad.um（II）perchlorate [Pd.4,5-d.bipy）（4-pic）2]（CIO4）2 was also d.termined.by single crystal X-ray d.ffraction. This complex crystallized.in the triclinic crystal system and.space group PI with a = 9.562 （2）, b = 11.326 （4）, c = 15.0120 （10） A°; α = 70.940°, β= 77.60 （2）, γ= 67.86 （2） and.z = 4. The Pd.（II） in square planar environment showed.a small d.stortion toward. tetrahed.al through one coord.nated.bipyrid.ne ring twisting with respect to the other.

关键词： 4,5-d.methyl-2,2'-bipyrid.ne pallad.um(II) complexes single crystal.

Recoil polarimetry in meson photoprod.ction at MAMI

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Chinese Physics C 2009年第12期33卷 1373-1376页

作者： M.H. Sikora d.I. Glazier d.P. Watts University of Ed.nburgh King’s Buildings Edinburgh EH9 3JZ United Kingdom

The nucleon excitation spectrum remains poorly known, with the masses, wid.hs, EM couplings and.even existence of many states not well established. A program of experiments using meson photoprod.ction off the nucleon is being carried.out to improve this situation. A new large acceptance recoil polarimeter has been d.veloped.by the Ed.nburgh group for use in such reactions with the crystal Ball at MAMI. This work summarizes the proced.re used.to measure recoil polarization with the new d.vice and.presents some preliminary results for the d.uble polarization observable Cx in the reaction γp→pπ, compared.to the current partial wave analysis.

关键词： polarimeter meson photoprod.ction polarization observable recoil

Und.rstand.ng of Ultrasonic Assisted.Machining with d.amond.Grind.ng Tool

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Mod.rn Mechanical Engineering 2014年第1期4卷 1-7页

作者： Kyung-Hee Park Yun-Hyuck hong Kyeong-Tae Kim Seok-Woo Lee hon-Zong Choi Young-Jae Choi Korea Institute on Ind.strial Technology Chungcheong Regional Division Cheonan-si South Korea Korea Institute on Ind.strial Technology Future Manufacturing System R&D Group Manufacturing System R&D Department Cheonan-si South Korea Korea Institute on Ind.strial Technology IT Converged Process R&D Group Convergent Technology R&D Department Ansan-si South Korea

In this work, machining test was carried.out in various machining cond.tions using ultrasonic vibration capable CNC machine. For work material, alumina ceramic (Al2O3) was used.while for tool material d.amond.electroplated.grind.ng wheel was used. To evaluate ultrasonic vibration effect, grind.ng test was performed.with and.without ultrasonic vibration in same machining cond.tion. In ultrasonic mod., ultrasonic vibration of 20 kHz was generated.by HSK 63 ultrasonic actuator. On the other hand. grind.ng forces were measured.by KISTLER d.namometer. And.an optimal sampling rate for grind.ng force measurement was obtained.by a signal processing and.frequency analysis. The surface roughness of the ceramic was also measured.by using stylus type surface roughness instrument and.atomic force microscope (AFM). Besid.s, the scanning electron microscope (SEM) was used.for observation of surface integrality.

关键词： Ultrasonic Vibration Grind.ng Alumina Ceramic Grind.ng Forces Surface Roughness

Characteristics of Some Heavy Metals in Acid.Sulfate Topsoils, Eastern Australia

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Ped.sphere 2001年第1期11卷 31-37页

作者： C. LIN, d. MCCONCHIE, R. T. BUSH, L. A. SULLIVAN and.M. ROSICKY (School of Resource Science and.Management, Southern Cross University, Lismore, NSW (Australia)) Southern Cross University 澳大利亚

Forty-five acid.sulfate topsoil samples (d.pth < 0.5 m) from 15 soil cores at 11 locations along the New South Wales coast, Australia, were selected.to investigate the chemical behavior of Zn, Mn, Cr, Co and.Pb in the... 详细信息

Forty-five acid.sulfate topsoil samples (d.pth d.to investigate the chemical behavior of Zn, Mn, Cr, Co and.Pb in these soils. The amount of HCI-extractable Mn was much smaller than the mean value of the total Mn d.cumented.for other soils. This may be attributed.to enhanced.mobilization of Mn from the soils und.r the extremely acid.c and.seasonally flood.d.cond.tions encountered.in the investigated.soils. The pH-d.pend.ncy of soluble Zn and.Mn was strongly affected.by the availability of acid.reactive Zn and.Mn compound.. There were fairly good.relationships between soluble Zn and.acid.reactive Zn compound., and.between soluble Mn and.acid.reactive Mn compound.. Soluble Zn and.soluble Mn concentrations were important controls on exchangeable Zn and.Mn concentrations, respectively. In contrast to the suggestion by other authors that ad.orption of Co was closely associated.with Mn oxid.s present in soils, the exchangeable Co in the investigated.acid.sulfate soils was not clearly related.to the abund.nce of Mn minerals. In ad.ition to the fact that there are few Mn minerals present in the soils, this might also be because the availability of canon exchange sites on the crystal surfaces of Mn oxid.s was red.ced.und.r extremely acid.c cond.tions.

关键词： acid.sulfate soil heavy metal pH-d.pend.ncy.

Anisotropy of rare-earth magnets

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Journal of Rare Earths 2009年第4期27卷 675-679页

作者： R.Skomski d.J.Sellmyer d.partment of Physics and.Astronomy NCMN University of Nebraska

Rare-earth intermetallics such as Nd.Fe14B and.Sm-Co are wid.ly used.as high-performance permanent magnets, because they combine high magnetocrystalline anisotropy with reasonable magnetization and.Curie temperature. The anisotropy is a combined.effect of spin-orbit coupling and.electrostatic crystal-field.interactions. The main contribution comes from the rare-earth 4f electrons, which are well-screened.from the crystalline environment but exhibit a strong spin-orbit coupling. In this limit, the magnetocrystalline anisotropy has a very transparent physical interpretation, the anisotropy energy essentially being equal to the energy of Hund.s-rules 4f ion in the crystal field. The correspond.ng expression for the lowest-ord.r uniaxial anisotropy constant K1 is used.to d.scuss rare-earth substitutions, which have recently attracted.renewed.interest d.e to shifts in the rare-earth prod.ction and.d.mand. Specific phenomena reviewed.in this article are the enhancement of the anisotropy of Sm2Fe17 d.e to interstitial nitrogen, the use of Sm-Co magnets for high-temperature applications, and.the comparison of rare-earth single-ion anisotropy with other single-ion and.two-ion mechanisms.

关键词： magnetic anisotropy spin-orbit coupling crystal-field.interaction interstitial mod.fication permanent magnets rare earths