The Thermal Conductivity of Monocrystalline Gallium Garnets Doped with Rare-Earth Elements and Chromium in the Range 6–300 K

The effect of the additions of rare-earth elements Nd, Sm, Eu and Tb on the thermal conductivity of gadolinium-gallium garnets and besides the influence of the joint doping with Nd and Cr on the thermal conductivity of gadolinium-gallium and more compound gadolinium-scandium-gallium, gadolinium-magnesium-zirconium-gallium and yttrium-scandium-gallium garnets have been investigated.     

Nonlinear Optical Properties of Isomorphic Family of Crystals with Yttrium-Aluminium Borate (YAB) Structure

The second harmonics generation of Nd-laser radiation (λ = 1.06 microns) of the isomorphic family of crystals with yttrium-aluminium borate (YAB) structure — RAl₃(BO₃)₄ (R = Y, Sm, Eu, Gd, Dy, Er, Ho, Tu) — investigated using the powder method and the theoretical calculation of SHG–coefficients — are reported. The refraction indices (for λ = 5481 Å) and optical sign for all studied YAB-type crystals are determined with the help of the immersion method. All studied crystals possess PM direction and oee-interaction. The SH-intensity is of KDP order of magnitude, with reasonable correlation of experimental and theoretical data. Theoretical analysis of the contributions of different ions to the integral d magnitude has shown identical signs for all ion species in YAB structure type.     

非晶金刚石薄膜的sp3键成分的XPS谱研究

把非晶金刚石薄膜的XPS C1s谱分解为中心在284.4±0.1eV 和285.2±0.1eV的两个高斯特征峰,分别对应于碳薄膜中的sp2C和sp3C.用这两个高斯特征峰的面积除以C1s谱的总面积,得出非晶金刚石薄膜中sp2C和sp3C的比例.用上述方法对sp3C比例不同的一组样品进行了分析计算,并与先前用紫外-可见光吸收光谱和拉曼光谱对同一组样品分析得出的结果进行了比较,结果表明:用XPS谱能简便而有效地定量确定非晶金刚石薄膜中sp2C和sp3C的比例,且这种方法适用于所有功能碳薄膜.     

Refined Structure of Langmuir Lysozyme Films on Single-Crystal Silicon Wafers According to X-Ray Reflectivity Data

Crystallography Reports - Thin lysozyme films on single-crystal silicon wafers have been studied by X-ray reflectivity. The films have been formed using the modified Langmuir–Schaefer method...     

Study of the Radiation Resistance of Endohedral Fullerenes of Rare-Earth Elements and Their Water-Soluble Derivatives

Endohedral metallofullerenes Me@C_2n (n = 30–50), their hydroxylated derivatives Me@C_2n(OH)_38–40 (Me = Tm, Ho, Eu, Sm, Co), and fullerenol С₆₀(OH)₃₈ have been synthesized The radiation resistance of these structures under irradiation in reactor by thermal and fast neutron fluxes in the fluence range of 1018–1019 cm^–2 (cadmium ratio of ~10) has been analyzed. Endofullerenols are shown to be more stable in comparison with initial endohedral fullerenes; the molecules containing Eu and Sm (atoms characterized by the largest slow-neutron absorption cross section) turned out to be most stable. The mechanism of the formation of secondary Eu and Sm endofullerenols is discussed taking into account the neutron capture and emission of γ quanta by excited nuclei, which acquire the recoil energy.     

Two Different Compounds Formed from Copper(II) tetrafluoridoborate and [1,2,4]triazolo[1,5-a]pyrimidine. Synthesis,Spectroscopy and Single-Crystal Structures

Abstract  

Two coordination compounds copper(II) with tetrafluoridoborate as the anion and [1,2,4]triazolo[1,5-a]pyrimidine (abbreviated as tp) as the ligand are presented, together with their crystal structure and spectroscopic properties. A light blue compound [Cu(tp)₄(H₂O)₂](BF₄)₂(CH₃OH) (1) with a tetragonal chromophore and a dark blue compound [Cu(tp)₅](BF₄)₂(CH₃OH) (2) are formed from the same batch. Compound (2) has a quite unusual geometry for Cu(II) with just 5 tp ligands, homoleptically coordinated to the metal ion. Both compounds show interesting hydrogen-bond interactions in the solid state, where coordinated water is intramolecularly bound to non-coordinated N atoms of tp (in 1), and methanol is attached to the anion (in 2).     

水热法制备微米级钇铝石榴石(YAG)晶体

本文采用水热法,以Al(OH)3和Y2O3为前驱物,3 mol/L KOH作矿化剂,高温430 ℃,反应24 h,合成了微米级Y3Al5O12晶体.对合成材料的结构和形貌进行了测量分析,用差示扫描量热仪(DSC)和热重分析仪(TGA)测量分析了热性能.实验结果表明,所合成产物的成分、结构与前驱物中Y2O3与Al(OH)3的摩尔比有关.当Y∶ Al的摩尔比为1∶ 3时合成的纯相钇铝石榴石Y3Al5O12(YAG)晶体,呈立方体形,最大尺度超过100 μm.     

The Process of Formation of Epitaxial Cadmium and Zinc Oxide Films by Interaction of Single-Crystal AIIBVI Layers with Oxygen

The results of electron microscopic and electron diffraction investigation of the surface during annealing of single-crystal A^IIB^VI (CdS, CdSe, ZnSe, ZnS) films in the presence of oxygen are reported. It is shown that the behaviour of islands of cadmium oxide formed by chemical interaction between O₂ and the CdS, CdSe substrate in the process of growth resembles that of the nuclei in film condensation. CdO films become “continuous” more quickly, if the size of blocks of substrate-epitaxial A^IIB^VI film is larger. Epitaxial ZnO films formed on the surface of epitaxial ZnS and ZnSe layers are of a wurtzite structure or a cubic structure with the parameter a = 4.5 Å.     

乙醇溶液中电沉积CuInSe2(CIS)薄膜过程研究

采用三电极体系,以钼片为工作电极,大面积铂网为辅助电极,饱和甘汞电极(SCE)为参比电极,以氯化铜、氯化铟、亚硒酸为原料,在无水乙醇溶液中,用阴极恒流和恒压两种沉积方法制备出CIS前驱体薄膜,采用XRD和EDAX对制备的薄膜进行了表征,分析了沉积方式、镀液离子浓度、导电盐(LiCl)含量及热处理工艺等因素对薄膜成分及形貌的影响,并对电沉积CIS薄膜的机理进行了初步探讨.在最优条件下所制备的薄膜成分接近标准比且表面致密、均匀.     

Morphological Specific Features of (100)-Textured Polycrystalline Diamond Films

Crystallography Reports - The morphological specific features of (100)-textured polycrystalline diamond films, grown by chemical vapor deposition (CVD) and consisting of micrometer-sized...     

金刚石膜在Si(100)衬底上的选择沉积

采用自行设计的微波等离子体化学气相沉积系统,利用铜网作为模板实现了在Si(100)衬底上金刚石膜的选择沉积.用场发射扫描电子显微镜(SEM)、Raman散射谱对样品进行了表征与分析.并与同样生长条件下未采用模板时得到的金刚石样品进行了比较.结果发现,采用模板后,金刚石膜的成核密度和质量都得到很大提高.     

PICTS测试CdZnTe晶体中深能级缺陷

详细阐述了光生电流瞬态谱(PICTS)的原理、结构和搭建过程,其中搭建过程中采用的激光器波长为730nm,功率为50 mW,测试温度范围在液氮温度至常温之间.利用低压垂直布里奇曼法制备了掺In的CdZnTe晶体样品,采用PICTS研究了样品中的主要缺陷能级,确定了能级位置在0.471 eV和0.15 eV的两个深中心,这两个缺陷分别可能是VCd2-和A中心(InCd+-VCd2-)-.     

Edge-Defined Film-Fed (EFG) Growth of Rare-Earth Orthovanadates REVO4 (RE=Y,Gd): Approaches to Attain High-Quality Shaped Growth

In spite of their superior laser and polarizer properties rare-earth orthovanadates (REVO₄) single crystals have not been adopted yet into extensive industrial applications because of crystal growth difficulties. The main problems of CZ technique are compositional change and diameter instability. This work presents the first attempt to apply the edge-defined film-fed growth (EFG) technique by which well-shaped REVO₄crystals have been grown directly. The capillary properties of YVO₄ and GdVO₄ melt have been measured. The applicability of shaped growth for rare-earth orthovanadate family was approved by successful EFG growth of transparent rod-like macro-defect-free single crystals of YVO₄ and GdVO₄. We address two main approaches to enhance the quality of EFG crystals: (i) meniscus and crystal shape stability dependence on die top shape and (ii) the strategy of effective operating control. Concave die top was found to be the best choice for high-quality EFG growth of REVO₄ along [001] direction. The spectral analysis of weight signal from growing crystal was shown to be a useful feedforward clue to prevent crystallinity degradation at a very early stage. A reasonable stability of the EFG process was achieved using [211], [101], [001] and [100] pulling directions.     

Nd:NaY(WO4)2激光晶体光谱性能研究

Nd:NaY(WO4)2 是一种性能优良的激光晶体.本文采用提拉法生长了Nd:NaY(WO4)2晶体,测试了该晶体的吸收光谱和光荧光光谱.结果表明,该晶体在804nm、752nm、586nm附近有较强、较宽的吸收峰,适合于LD泵浦.从光荧光光谱得到发射波长分别为1064nm和1350nm,并计算了晶体的吸收截面和发射截面.     

采用MOCVD方法在GaAs衬底上生长ZnO(002)和ZnO(100)薄膜

采用金属有机化学汽相沉积生长法（MOCVD）,在不同的衬底表面处理条件和生长温度下,在GaAs衬底上生长出了ZnO薄膜。随着化学腐蚀条件的不同,可生长出优先定位不同的ZnO（100）和ZnO（002）薄膜。该薄膜的晶体结构特性是由X光衍射谱仪（XRD）所获得的,而其光学特性是由光荧光谱仪（PL）来测的。与ZnO（002）相比,ZnO（100）薄膜具有更优越的晶体结构特性,并且在同样的生长温度下都具有相似的光学特性。对于腐蚀条件不同的GaAs衬底所进行的XPS分析结果表明,ZnO薄膜优先定位变化的主要原因在于腐蚀过程中形成的富As层。     

Possibilities of X-Ray Absorption Spectroscopy in the Total External Reflection Geometry for Studying Protein Films on Liquids

Crystallography Reports - XANES spectra of protein films (hemoglobin and alkaline phosphatase) formed on the surface of a liquid subphase in a Langmuir trough have been obtained experimentally. The...