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High-pressure Raman spectra of copper metagermanate(CuGeO3) are presented,.Above 70 kbar copper metagermanate becomes amorphous,in the range of 70-125 kbar the transition is veversible,above 141 kbar is irreversible.The recrystallization process of pressure-induced amorphous state were investigated. 相似文献
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高压拉曼散射研究表明.CuGeO3,Li2GeO3和Li6Ge2O7三种晶体分别在7,12和11GPa压力下转变为非晶。在高于起始转变压力以上一定范围压致非晶是可逆的,CuGeO3,Li2GeO3和Li6Ge2O7压致非晶的不可逆转变压力分别为14.1,20和20GPa。压致非晶CuGeO3的重新晶化温度在600℃附近。锗酸及系列晶体的压致非晶化与它们的成份和结构有关,随着在这一系列晶体中Li2O含量的增加,压致非晶化的压力趋于减小。 相似文献
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本文主要介绍压致非晶化研究的进展,其中包括我们对β—BaB_2O_4,LiB_3O_5,Pb_5Ge_3O_11和Li_2Ge_7O_(15)的拉曼散射研究结果。综述了压致非晶的结构特征,压致非晶转变机制和重新晶化过程。 相似文献
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本文用X射线衍射、Eu2+的发射谱与激发谱、拉曼谱以及扫描电镜(SEM)颗粒形貌,研究了常压下合成的具有正交结构的SrB2O4:Eu2+晶体在3.0~7.0 GPa压力下的晶态非晶化现象。分析结果表明,压力导致晶粒细化和晶态非晶化。晶粒尺寸由常压下的微米量级细化为几十个纳米量级,随压力的变化为:2 μm(0.1 MPa),49.4 nm(3.0 GPa),29.7 nm(5.0 GPa),25.1 nm(7.0 GPa)。晶态与非晶态体积比随压力增加而减小,分别为:70/30(3.0 GPa),63/37(5.0 GPa),57/43(7.0 GPa)。在压力下Eu2+是处在晶态与非晶态两种不同的低对称的环境中。纳米级晶粒是以亚晶粒形式存在于微米级大晶粒中的,压致非晶态可能组成了纳米亚晶粒的界面区。 相似文献
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本文采用超声脉冲回波法在4.2K—300K温区内测试了锗酸铋晶体[110]和[111]晶向的超声纵波衰减与温度的关系,结果在50K附近均出现由于激活弛豫过程所引起的大的异常衰减峰;本文还用脉冲回波重合法精密测定了[100],[110]和[111]晶向的超声纵波和横波的声速,并由此计算出弹性常数C11,C44和C12。 相似文献
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本文叙述了锗酸铋晶体的生长。采用二波耦合光路测试BGO晶体的衍射效率和增益系数,研究BGO晶体的二波耦合中光波的位相变化。 相似文献
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Na_2ZnGeO_4相晶体是强碱性锗酸盐中最有趣的一种物质。用锰浓激活的这种晶体具有很亮的光致发光、磨擦发光、阴极射线发光和X射线发光,在其上观察到明显的压电效应,并发现有直流场致发光。 我们测量了掺锰的相晶体的室温和液氮温度下的光致发光光谱。用普通的测量方法:用装有光电倍增管—51的单色仪—2分光,并将光谱自动记录在自记器—09上。激发光波长是365毫微米,激发光源是—4灯。研究了从6种不同实验得来的14个晶体。在晶体的生长过程以 相似文献
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Theoretical Strength of Face-Centred-Cubic Single Crystal Copper Based on a Continuum Model 下载免费PDF全文
The constitutive relation of single crystal copper based on atomistic potential is implemented to capture the nonlinear inter-atomic interactions. Uniaxial loading tests of single crystal copper with inter-atomic potential finite-element model are carried out to determine the corresponding ideal strength using the modified Born stability criteria. Dependence of the ideal strength on the crystallographic orientation is studied, and tension- compression asymmetry in ideal strength is also investigated. The results suggest that asymmetry for yielding strength of nano-materials may result from anisotropic character of crystal instability. Moreover, the results also reveal that the critical resolved shear stress in the direction of slip is not an accurate criterion for the ideal strength since it could not capture the dependence on the loading conditions and hydrostatic stress components for the ideal strength. 相似文献
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用分子动力学方法模拟计算了在初始温度为0 K时单晶铜中的冲击波结构,相互作用势采用铜的嵌入原子势(EAM),模拟计算结果表明即使是在初始温度为0 K的FCC晶体中,冲击波波阵面后的区域也会向平衡态演化。局域分析表明冲击波阵面后区域的压力、粒子速度、应变和温度随时间逐步变化到稳定态,在所研究的冲击波强度(约262 GPa)下,波后区域的平均压力、粒子速度、应变均在约1 ps内逐渐上升并达到稳定值。动能温度在波阵面处始终为最大值,随着冲击波的传播,波后非零温度区域逐渐扩大,不同时刻的粒子速度分布函数说明波后区域逐渐向热力学平衡态演化,并最终达到热力学平衡,进一步的分析说明局域平衡是系统向平衡态演化的基本过程。 相似文献
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2,2'-联咪唑类离子液体配位的双核铜配合物的合成、光谱表征及晶体结构研究 总被引:1,自引:0,他引:1
以2,2'-联咪唑为原料制得离子液体1,3,1'-三丁基-2,2'-联咪唑六氟磷酸盐,将此离子液体与醋酸铜配位得到了1,3,1'-三丁基-2.2'-联咪唑六氟磷酸盐配位的双核铜配合物.采用元素分析,IR,UV,ESI对其结构进行了表征.并用X-ray单晶衍射仪确定了其单晶结构,化合物属三斜晶系,空间群P-1晶胞参数α=0.84507(11)nm,b=1.11663(15)nm,c=1.6262(2)nm.α=96.640(2)°β=11.860(3)°,γ=98.091(3)°;V=1.4760(3)nm3,Dc=1.418g/cm3,Z=1,F(000)=654,μ=0.865mm-1. 相似文献
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将辐照硬化理论与晶体塑性理论结合, 运用ABAQUS有限元分析软件模拟辐照后多晶铜的拉伸过程。分析辐照效应对材料屈服强度、硬化过程、晶体变形等力学性能的影响, 研究位错密度的演化及空间分布规律。数值模拟表明: 辐照效应提高多晶铜的屈服应力, 影响不同阶段的硬化和软化现象; 辐照剂量增大导致位错密度增殖总体变缓, 空间不均匀度增大; 晶体的塑性变形及晶体转动也受到辐照的影响, 在相同的应变条件下, 辐照剂量越大, 晶体塑性变形程度越小, 塑性变形分布不均匀度变大, 同时晶体转动程度及转动角离散度增大。 相似文献
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结晶紫.溴酚蓝等色染料离子对浮选光度法测定铜 总被引:2,自引:0,他引:2
用PH=10的NaOH水溶液解析铜-2,2’-联喹啉-溴酚蓝(BPB)三元络合物,使BPB进入水相,向其中加入与BPB颜色相近的碱性染料结晶紫(CV),形成等色染普等离子对CV·BPB而被苯浮选,将浮选物溶于忆际最大吸收波长590nm处进行光度测定。由于两种染产等色并同时参与显色,使本方法具有较高的灵敏度。2,2‘-联喹啉为铜的特效试验,因此方法选择性亦好。ε=1.45×10^5L·mol^-1· 相似文献
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1, 8-(3, 6, 9-Trioxaundecane-1, 11-diyldioxy)xanthone (L), and its new Cu (II) complex [Cu·L·(CH3CN)2](ClO4)2 have been synthesized and characterized by 1H NMR, electrospray mass spectra (ESI-MS), elemental analyses, infrared spectra (IR) and X-ray single crystal diffraction.
The crystal structure of complex shows that Cu (II) ion is encapsulated within the macrocycle of L. The geometry around copper is a distorted square bipyramid with two acetonitrile molecules at axial position, and four macrocyclic
oxygens including the carbonyl oxygen on the equatorial positions. The interaction of Cu (II) complex with calf thymus DNA
(ct DNA) has been investigated by spectrophotometric titrations, ethidium bromide (EB) displacement experiments, circular
dichroism (CD) spectra and viscosity measurements. Rresults indicate that Cu (II) complex can intercalate into the DNA base
pairs by the plane of xanthone ring. Furthermore, the Cu (II) complex was tested against tumor cell lines including ECA109,
SGC7901and GLC-82 by MTT (microculture tetrazolium) method. The studies of DNA-binding agree with the effects on the inhibition
of tumor cells in vitro. 相似文献
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Tianzhi Yu Peng Liu Haifang Chai Jundan Kang Yuling Zhao Hui Zhang Duowang Fan 《Journal of fluorescence》2014,24(3):933-943
Two mononuclear Cu(I) complexes based on 2-(2-pyridyl)benzimidazolyl derivative ligand containing electron-transporting 1,3,4-oxadiazole group (L), [Cu(L)(PPh3)2](BF4) and [Cu(L)(DPEphos)](BF4), where L?=?1-(4-(5-(4-tert-butylphenyl)-1,3,4-oxadiazol-2-yl)benzyl)-2-(pyridin-2-yl)benzimidazole and DPEphos?=?bis[2-(diphenylphosphino)phenyl]ether, have been successfully synthesized and characterized. The X-ray crystal structure analyses of the ligand L and the complex [Cu(L)(PPh3)2](BF4) were described. The photophysical properties of the complexes were examined by using UV–vis, photoluminescence spectroscopic analysis. The doped light-emitting devices using the Cu(I) complexes as dopants were fabricated. With no electron transporting layers employed in the devices, yellow electroluminescence from Cu(I) complexes were observed. The devices based on the complex [Cu(L)(DPEphos)](BF4) possess better performance as compared with the devices fabricated by the complex [Cu(L)(PPh3)2](BF4). The devices with the structure of ITO/MoO3 (2 nm)/NPB (40 nm)/CBP:[Cu(L)(DPEphos)](BF4) (8 wt%, 30 nm)/BCP (30 nm)/LiF (1 nm)/Al (150 nm) exhibit a maximum efficiency of 3.04 cd/A and a maximum brightness of 4,758 cd/m2. 相似文献