地球深部探索与高压研究

地球内部是一个复杂的高温高压系统,地球核心的压力约360GPa,温度约5000℃,地球内部物质在高温高压条件下演化成为目前的地球层圈结构,在地球表面发生的许多重大的地质事件,都与高温高压条件下地球深部物质的性质密切相关,文章介绍了近年来高压物质科学的某些研究现状,并提出了若干地球科学中急待研究的科学问题。     

Z切LiTaO3单晶的冲击相变

高压相变是高压科学研究中的一个热点课题，它探索和揭示物质在高温高压极端条件下结构和物态变化的临界现象和规律，在凝聚态物理、材料科学、地球和行星科学研究中占有重要的地位，同时也是武器物理研究的一项重要内容。LiTaO3是一种重要的功能材料，且具有典型的ABO3晶体结构。有关它的高压相变研究，目前人们从有限的静压和动高压实验数据获得的认识还存在较大的分歧，如相变起始压力报道差别较大，高压相结构还不很清楚，有较高的科学研究价值。本项目通过冲击压缩实验结合第一性原理理论计算开展了LiTaO3单晶的冲击相变研究。     

欢迎投稿

正《高压物理学报》是我国高压物理领域唯一的专业性学术刊物。征稿内容为:高温高压下材料的力、热、光、电、磁等特性,高温高压下材料的微观结构和相变,高温高压物态方程,高压合成新材料,高压地球和行星科学,动态及静态高压加载和测试技术,高压下物质的动态响应,冲击和爆轰现象等。《高压物理学报》接受中、英文稿件。     

欢迎投稿

正《高压物理学报》是我国高压物理领域唯一的专业性学术刊物。征稿内容为:高温高压下材料的力、热、光、电、磁等特性,高温高压下材料的微观结构和相变,高温高压物态方程,高压合成新材料,高压地球和行星科学,动态及静态高压加载和测试技术,高压下物质的动态响应,冲击和爆轰现象等。《高压物理学报》接受中、英文稿件。自1987年创刊以来,《高压物理学报》取得了较大的成就。     

《高压物理学报》征稿简则

1 .《高压物理学报》是高压物理学科的学术刊物 ,在国内外公开发行。本刊力求及时报道高压物理学科基础理论和应用研究方面具有创新性、高水平、有重要意义的研究成果 ,读者对象为从事高压物理专业及相邻专业 (如材料科学、爆炸力学、地球物理、天体物理等 )的国内外科技工作者。　　 2 .《高压物理学报》进入了国际上主要检索系统 ,如 :ＥＩ,ＣＡ等 ;是中国物理学类核心期刊。　　 3.征稿内容为 :动态及静态高压技术 ,人工合成新材料 ,高温高压下材料的力学、光、电、磁等特性以及物质微观结构的研究 ,动态及静态高压研究中的测试技术 ,高…     

电介质物理

物理学是研究物质基本运动规律的科学，按照物质的基本运动形式，物理学最早的分支为力学、声学、热学．电磁学、光学和原子物理学，后来按照所研究的物质的结构层次．又将物理学分为天体物理、地球物理、凝聚态物理、原子和分子物理、核物理和基本粒子等．     

《高压物理学报》征稿简则

《高压物理学报》是我国高压物理领域唯一的专业性学术刊物，在国内外公开发行。《高压物理学报》力求及时报道高压物理学科基础理论和应用研究方面具有创新性、高水平、有重要意义的研究成果，读者对象为国内外科技工作者。《高压物理学报》征稿内容为动态及静态高压技术，人工合成新材料，高温高压下材料的力学、光、电、磁等特性以及物质微观结构的研究，动态及静态高压研究中的测试技术，高温高压下的相变，高温高压物态方程等。《高压物理学报》接受中、英文稿件。     

我国高压物理研究的若干近期进展

本文简述了近年来我国在高压物理研究领域（高压力产生及其检测技术，物态方程，高压物性，高医相变）的若干进展，以及在地球物理、材料科学等方面的高压物理研究情况．     

欢迎投稿

正《高压物理学报》是我国高压物理领域唯一的专业性学术刊物。征稿内容为:高温高压下材料的力、热、光、电、磁等特性,高温高压下材料的微观结构和相变,高温高压物态方程,高压合成新材料,高压地球和行星科学,动态及静态高压加载和测试技术,高压下物质的动态响应,冲击和爆轰现象等。《高压物理学报》接受中、英文稿件。自1987年创刊以来,《高压物理学报》取得了较大的成就。2001年,《高压物理学报》被科技部和国家新闻出版总署评为"中国期刊方阵"双效期刊。国际主要检索系统Scopus、JSTChina、CA、EBSCO长期收录《高压物理学报》发表的文章。北京大学图书馆编著的《中文核心期刊要目总览》连续九版把《高压物理学报》列为物理学类核心期刊。     

欢迎投稿

正《高压物理学报》是我国高压物理领域唯一的专业性学术刊物。征稿内容为:动态及静态高压技术,人工合成新材料,高温高压下材料的力学、光、电、磁等特性以及物质微观结构的研究,动态及静态高压     

白光LED用新型绿色荧光粉Ca5(SiO4)2F2∶Eu2+的发光性能

采用高温固相法合成出系列绿色Ca5-xEu(SiO4)2F2荧光粉,并对其发光特性进行了研究.Eu2+ 离子在Ca5(SiO4)2F2基质中可被250～440 nm光有效激发发出绿光,适合作为UV-LED用绿色荧光粉.浓度猝灭实验结果表明,Eu2+离子的最佳掺杂摩尔分数为0.15,通过计算推测出Eu2+离子在Ca5-x...     

圆锥扫描式红外地球模拟器研究

针对适用于低轨道卫星的圆锥扫描式红外地球敏感器地面模拟试验、标定和可靠性测试等问题,采用开有120°V型槽的扇形冷板模拟地球弦宽、金属热板模拟地球热源的方案,研制了圆锥扫描式红外地球模拟器和零姿态模拟器,其能模拟卫星在低轨道上看到的地球,提供120°地球弦宽。     

Synthesis and luminescence of a novel conjugated europium complex with 6-parachloroaniline carbonyl 2-pyridine carboxylic acid

A novel organic ligand, 6-parachloroaniline carbonyl 2-pyridine carboxylic acid, and the corresponding europium complex, tris(6-parachloroaniline carbonyl-2-pyridine carboxylate) europium (III) have been designed and synthesized. The results showed that the synthesized product was a conjugated complex, emitting remarkable strong red luminescence, and was a good red luminescence material with good thermal stability. The ⁵D₀ lifetime of Eu³⁺ in the complex was examined using time-resolved spectroscopic analysis. The lifetime values for 1.0×10⁻⁵ mol/l ethanol solution of the complex and for the complex solid were 0.49±0.01 and 1.94±0.01 ms, respectively.     

Broad yellow orange emission from SrAl2O4:Pr phosphor with blue excitation for application to white LEDs

Photoluminescence excitation to intermediate atomic levels of rare earth activator ion (praseodymium) situated intragap in alkaline earth aluminate (AEA) SrAl₂O₄ has been tailored. This lead to blue excitation (2.7 eV) of large band gap AEA possible. Photoluminescence (PL) emission in the visible region extends from 525 to 650 nm corresponding to transition from ³P₀ and ¹D₂ excited states to different ³H_J and ³F_J states of Pr³⁺, broadened by crystal field effect of SrAl₂O₄. Thus SrAl₂O₄:Pr³⁺ promise to be a good candidate for solid state lighting in conjunction with blue LED.     

Concentration quenching of Eu in SrO·Al2O3:Eu phosphor

The luminescence of Eu²⁺ in alkaline earth aluminates of the type SrO·Al₂O₃ has been studied. In SrO·Al₂O₃:Eu²⁺ phosphor, green Eu²⁺ luminescence is observed from Eu²⁺ on the two different strontium sites present in the lattice. Their concentration quenching processes of the two inequivalent Eu²⁺ ions are investigated, respectively, and the corresponding concentration quenching mechanism is verified as dipole-dipole interaction. The value of the critical transfer distance is calculated.     

Hartmagnetische Legierungen der Seltenen Erdmetalle mit 3d-Metallen

The phase relations obtained from alloys of the rare-earth metals (RE) with 3d-metals are initially discussed, as well as the crystal structures and the general physical properties of the corresponding intermetallic compounds. The magnetic properties of RE-3d-compounds and the essential data of a hard-magnetic material are then summarized. The different steps in the production of RE-Co-permanent magnets are reviewed in relation to the underlying basic physical mechanisms. Finally, other possible hard-magnetic RE-3d-alloys and some general trends of physical and metallurgical investigations, necessary for the improvement of the RECo₅-magnets, are outlined.

     

稀土配合物Eu(asprin)_3phen发光特性的研究

将稀土配合物Eu(asprin)_3phen掺杂到导电聚合物PVK中,制成结构分别为ITO/PVK:RE配合物/LiF/AI(1),ITO/PVK:RE配合物/PBD/LiF/AI(2)的电致发光(EL)器件。发现二者的电致发光谱存在着较大的差别:在器件(1)中,来自Eu~(3 )的位于594nm(~5D_0→~7F_1)和614nm(~5D_0→~7F_2)处的发光强度大致相当,而在器件(2)中,EL主要来自Eu~(3 )位于614nm的发光,594nm处的发光很弱,与薄膜状态下的光致发光谱(PL)一致。并针对此现象进行了初步讨论。     

Pressure induced phase transition in rare earth mono-antimonides

Pressure induced structural phase transition of mono-antimonides of lanthanum, cerium, praseodymium and neodymium (LnSb, Ln=La, Ce, Pr and Nd) has been studied theoretically using an inter-ionic potential with modified ionic charge which parametrically includes the effect of Coulomb screening by the delocalized f electrons of rare earth (RE) ion. The anomalous structural properties of these compounds have been interpreted in terms of the hybridization of f electrons with the conduction band and strong mixing of f states of Ln ion with the p orbital of neighbouring antimonide ion. All the four compounds are found to undergo from their initial NaCl (B₁) phase to body centered tetragonal (BCT) phase at high pressure and agree well with the experimental results. The body centered tetragonal phase is viewed as distorted CsCl structure and is highly anisotropic with c/a=0.82. The transition pressure of LnSb compounds is observed to increase with decreasing lattice constant in NaCl phase. The nature of bonds between the ions is predicted by simulating the ion-ion (Ln-Ln and Ln-Sb) distances at high pressure. The calculated values of elastic constants are also reported.     

BaAl_(12)O_(19):Mn~(2+)和YPO_4:Tb~(3+)共混对等离子绿色发光体发光性能的改善

等离子体平板显示用绿色发光粉主要有硅酸盐(Zn2S iO4∶Mn2+)、铝酸盐(BaA l12O19∶Mn2+)、磷酸盐(YPO4∶Tb3+)和硼酸盐(YBO3∶Tb3+)4种体系。前两者具有量子效率高、色纯度好等优点,然而抗真空紫外辐照能力差,发光衰减时间长;Tb3+激活的磷酸盐和硼酸盐体系具有适宜的发光寿命,抗真空紫外辐射能力强,然而Tb3+的发射光是黄绿色,色纯度不够好,且发光亮度相对较弱。按一定的混合比率使BaA l12O19∶Mn2+和YPO4∶Tb3+均匀混合,组合这两种体系绿色发光粉各自的优点,优化了等离子体平板显示用绿色发光粉的整体性能。     

Ion sputtering of minerals and glasses: a first step to the simulation of solar wind erosion

Selected rockforming minerals (plagioclase, augite, olivine, ilmenite, silicate and metal phases of the meteorite “Brenham”) as well as silicate and phosphate glasses were irradiated with heavy ions (⁴He⁺, ¹⁴N+, ²⁰Ne⁺, ⁴⁰Ar+, ⁵⁶Fe+, Xe⁺ _nat) in the energy range of 50-130 keV in order to study ion-induced sputtering. Sputtering yields were measured independently by means of multiple beam interferometry and particle track autoradiography.

The theory of sputtering by Sigmund, modified by Smith, was used to convert experimental heavy ion sputtering yields to H⁺- and He⁺-sputtering yields of the same target. Taking into account solar wind irradiation conditions at the lunar surface, an estimate of lunar erosion rates due to solar wind sputtering is given for the targets studied.