Synthesis and characterization of sandwiched heteropolycompound

New complex K5O4Na4H5 [Sn-3(PW9O34)(2)]. 16N(2)O was prepared and its structure was determined by elemental analysis, IR, P-31, W-183 NMR, polarography, XPS and X-ray crystallography. The anion has A-alpha-Keggin structure. The new complex crystallize is the monoclinic, P2(1)/n with a = 1.3625 (3) nm, b = 2.3625 (5) nm, c = 2.9306 (6) nm, alpha = 90 degrees, beta = 99.67 (3)degrees, gamma = 90 degrees, V = 9.299 nm(3), Z = 4.

The NMR-spectroscopic and X-ray crystal-structural characterization of two Cp*Ir halfsandwich complexes containing the 1,2-dicarba-closo-dodecaborane-1,2-diselenolato ligand

The reaction of [Cp*IrCl2](2) with dilithium 1,2-orthocarborane-1,2-diselenolate 3 leads to the green 16-electron diselenolene complex [Cp*Ir{Se2C2(B10H10)}] (4) which takes up two-electron ligands such as trimethylphosphane to give the 18-electron diselenolate derivative [Cp*Ir(PMe3)-{Se2C2(B10H10)}] (5). The molecular structures of 4 and 5 were determined by X-ray crystal structure analysis. The Se-77-nuclear shielding in 4 is lower by almost 500 ppm relative to that in 5.

Comparison of wavelet transform methods - The compression of IR spectral data

In this paper, an introduction of wavelet transform and multi-resolution analysis is presented. We describe three data compression methods based on wavelet transform for spectral information,and by using the multi-resolution analysis, we compressed spectral data by Daubechies's compactly supported orthogonal wavelet and orthogonal cubic B-splines wavelet, Using orthogonal cubic B-splines wavelet and coefficients of sharpening signal are set to zero, only very few large coefficients are stored, and a favourable data compression can be achieved.

Studies on blends of LLDPE and polar polymers compatibilized by a random copolymer

Compatibilization of blends of Linear low-density polyethylene (LLDPE)-poly(methyl methacrylate) (PMMA) and LLDPE-copolymer of methyl methacrylate (MMA) and 4-vinylpyridine (poly(MMA-co-4VP) with poly(ethylene-co-methacrylic acid) (EMAA) have been studied. Mechanical properties of the LLDPE-PMMA blends increase upon addition of EMAA. In order to further improve interfacial adhesion of LLDPE and PMMA, 4-vinyl pyridine units are introduced into PMMA chains, or poly(MMA-co-4VP) is used as the polar polymer. In LLDPE-poly(MMA-co-4VP)-EMAA blends, interaction of MAA in EMAA with 4VP of poly(MMA-co-4VP) causes a band shift in the infrared (IR) spectra. Chemical shifts of N-1s binding energy in X-ray photoelectronic spectroscopy (XPS) experiments indicate a transfer of proton from MAA to 4VP. Scanning electron microscopy (SEM) pictures show that the morphology of the blends were improved upon addition of EMAA. Nonradiative energy transfer (NRET) fluorescence results attest that there exists interdiffusion of chromophore-labeled LLDPE chains and chromophore-labeled poly(MMA-co-4VP) chains in the interface. Based on experimental results, the mechanism of compatibilization is studied in detail. Compatibilization is realized through the interaction between MAA in EMAA with 4VP in poly(MMA-co-4VP). (C) 1999 John Wiley & Sons, Inc.

铁表面四苯基卟啉蒸汽沉积膜形成和结构研究

在铁表面进行四苯基卟啉((TPP)H2)蒸汽沉积处理，获得了具有一定耐蚀性的膜层．采用XPS、SEM和STM技术对成膜过程及膜的结构和组成进行了研究．发现在铁表面上进行(TPP)H2蒸汽沉积处理形成沉积膜时，首先在样品表面形成比较均匀覆盖的基础层．此后，膜的生长是以不连续的颗粒形式进行的．沉积膜外层是(TPP)H2的物理沉积，内层的(TPP)H2发生了一定变化，但没有生成铁卟啉．提出了沉积膜的氢键作用模型.

α-氨基酸的光电子能谱和质谱研究

用光电子能谱(XPS)和质谱(MS)方法研究了10种α-氨基酸.讨论了由于氨基酸酸烃基基团的差异,氮原子内层电子结合能化学位移的变化.用XPS和MS方法分别探讨了烃基对G-NH_2键的影响.

梳状高分子固体电解质共混体系的FT-IR研究

用傅立叶变换红外光谱对乙烯基甲醚/交替马来酸酐共聚物多缩乙二醇酯体系(CBP和CBPS单离子体系)和聚氧化乙烯共混物及其盐复合物的结构和相容性进行了研究，对主要红外光谱峰作了归属。结果表明，CBP与PEO、CBP、PEO和LiClO4分子间作用力较弱，易出现相分离，温度变化对CBP/PEO的相容性无影响，只影响PEO的结晶，加入LiClO4抑制了PEO的结晶。在CBPS/PE共混体系中存在着强的离子—偶极相互作用，改善了相容性，得到了热力学相容体系。共混比影响离子—偶极键浓度，对键强影响不大，此外还有弱的偶极—偶极相互作用存在

有机锡化合物的光电子能谱和质谱研究Ⅲ

本文利用光电子能谱(XPS)和质谱(MS)研究了12种有机锡化合物。通过XPS和MS讨论了化合物中取代基对锡内层电子的影响及对SnO键的影响。结果表明XPS和MS对有机锡化合物某些化学键性质的讨论具有互补性。

TiO_2纳米粉的热处理过程研究

用溶胶凝胶法制备出纳米凝胶粉，于不同温度下热处理形成纳米晶，研究热处理温度对粒子大小、形貌、品相转变及吸附能力的关系．XRD、FT-IR、Raman光谱研究表明200～600℃热处理1h的TiO2纳米晶为锐钛矿相，在700℃热处理的纳米晶为锐钛矿相与金红石相共存，800℃热处理的纳米晶完全为金红石相;TEM、TG、XPS的结果证明热处理温度越高，纳米粒子的粒径越大，吸附能力也越弱.

(Ce_(0.8)RE_(0.2))_(1-x)M_xO_(2-δ)固体电解质的溶胶-凝胶合成及其电性质

利用溶胶 凝胶法合成了 (Ce0 .8RE0 .2 ) 1-xMxO2 -δ(RE :稀土 ,M :碱土 )系列固体电解质 ,XRD表明 80 0℃即形成萤石结构 ,较高温固相反应合成温度低约 70 0℃ .测定了样品的电导率和阻抗谱 .XPS测试表明 ,掺杂碱土氧化物后吸附氧浓度明显增大 ,氧空位增多 ,电导率和氧离子迁移数增大 ,改善了CeO2 基固体电解质的性能 .讨论了碱土及稀土离子对电性质的影响 .(Ce0 .8Sm0 .2 ) 1-0 .0 5 Ca0 .0 5 O2 -δ80 0℃时电导率0 1 2 6S·cm-1,氧离子迁移数 0 .99.

聚酰亚胺/无机物纳米杂化材料的研究 I 聚酰亚胺(HQDPA/DMMDA)-TiO_2纳米杂化物的合成与表征

将钛酸丁酯经乙酸修饰改性和稳定化后在杂化过程中用作TiO2前体，采用溶胶—凝胶法由可溶性聚酰亚胺(HQDPA/DMMDA)与经修饰改性的钛酸丁酯溶液混合， 进而制得聚酰亚胺TiO2杂化材料．XPS分析表明钛酸丁酯已转化成TiO2，TEM则显示TiO2以球状微粒均匀分散在聚酰亚胺基体中，粒径为30～60nm．含10%TiO2的杂化膜是具有高热稳定性与韧性的薄膜，其介电常数为3

Reaction of halfsandwich iridium polychalcogenide complexes with dimethyl acetylenedicarboxylate. Molecular structure of Cp*Ir[S2C2(COOMe)(2)]

The pentamethylcyclopentadienyl iridium complexes Cp*Ir(PMe3)(E-n) (E = S, n = 4, 5 or 6; E = Se, n = 2 or 4 E = Te, n = 2) react with dimethyl acetylenedicarboxylate to give Cp*Ir(PMe3)[E2C2(COOMe)(2)] compounds which tend to lose the trimethylphosphine ligand; the molecular structure of the dithiolene derivative, Cp*Ir[S2C2(COOMe)(2)], has been determined.

The use of half-sandwich iridium dithiolate and diselenolate complexes, Cp*Ir(L)(ER)(2) (L = CO, PMe3, PPh3; ER = SPh, SePh, SeMe), for the synthesis of heterodimetallic compounds. The molecular structure of Cp*Ir(CO)(mu-SePh)(2)[Mo(CO)(4)]

Carbonyl-iridium half-sandwich compounds, Cp*Ir(CO)(EPh)(2) (E = S, Se), were prepared by the photo-induced reaction of Cp*Ir(CO)(2) with the diphenyl dichalcogenides, E2Ph2, and used as neutral chelating ligands in carbonylmetal complexes such as Cp*Ir(CO)(mu-EPh)(2)[Cr(CO)(4)], Cp*Ir(CO)(mu-EPh)(2)[Mo(CO)(4)] and Cp*Ir(CO)(mu-EPh)(2)[Fe(CO)(3)], respectively. A trimethylphosphane - iridium analogue, Cp*Ir(PMe3)(mu-SeMe)(2)[Cr(CO)(4)], was also obtained. The new heterodimetallic complexes were characterized by IR and NMR spectroscopy, and the molecular geometry of Cp*Ir(CO)(mu-SePh)(2)[Mo(CO)(4)] has been determined by a single crystal X-ray structure analysis. According to the long Ir...Mo distance (395.3(1) Angstrom), direct metal-metal interactions appear to be absent. (C) 1998 Elsevier Science S.A. All rights reserved.

La_(0.2)Ca_(0.8)MnO_3催化剂活性相的结构和形成机理

利用TG，DTA，XRD和XPS方法研究了La0.2Ca0.8MnO3催化剂的结构和形成机理．样品用La，Ca，Mn混合硝酸盐制备．随着焙烧温度的升高发生了一系列的固相反应，发现氨氧化催化剂催化活性与生成的CaMnO3含量成正比．在900℃制备的含有CaMnO3，La0.575Ca0.425MNO3，Mn2O3和La2O3的混合物是氨氧化最佳催化剂，活性相是CaMnO3，并具有大量的氧空穴.

杂多阴离子柱撑水滑石层柱相互作用的光电子能谱研究

本文用Ｘ－光电子能谱（ＸＰＳ）仪对二十二种同多和杂多阴离子柱撑水滑石（简称ＰＯＭ－ＬＤＨｓ）层和柱中元素电子结合能的化学位移进行了研究。同时通过ＩＲ、ＸＲＤ的分析，对ＸＰＳ结果的讨论提供了一定的补充，探讨了同层不同柱，同柱不同层的ＰＯＭ－ＬＤＨｓ的层柱相互作用机理。