Preparation and crystal structure of Guanidinium Cyclododecaphosphate Telluric Acid Hydrate: [C(NH2)3]12P12O36 · 12 Te(OH)6 · 24H2O

The title compound ist the first example of an adduct between telluric acid and the twenty four membered ring anion of a cyclododecaphosphate. [C(NH₂)₃]₁₂P₁₂O₃₆ · 12 Te(OH)₆ · 24 H₂O crystallizes trigonal (rhomboedral: R3) with Z = 3 and the unit-cell dimensions a = 15.854(9), c = 51.26(2) Å in the hexagonal setting. The crystal structure was solved by direct methods and refined to a final R value of 0.031. It is characterized by a succession of three different typs of alternating layers perpendicular to the c direction. This layers are connected only by hydrogen bonds. The individual layers are built up of A: P₁₂O₃₆ anions, guanidinium cations and water of crystallisation, B: hexagonal arranged Te(OH)₆ groups and guanidinium cations and C: water of crystallization.     

Characterization of Carbohydrates in Paper and Paper Pulps Using Anion Exchange Chromatography and Principal Component Analysis

In the course of this investigation, a method for the characterization and differentiation of paper pulps was developed. After hydrolyzation of the papers and the respective raw pulps with trifluoroacetic acid, the hydrolyzates were analyzed with respect to their carbohydrate composition using ion exchange chromatography. The variations in carbohydrate composition mainly arise from the various hemicelluloses of the papers and pulps. The chromatographic results were then further processed using principal component analysis which allows correlating the various papers to different pulp materials.     

Binding of hexacyanoferrate(II) by aliphatic amines in aqueous solution

The stability of hexacyanoferrate(II)-amine(methylamine, ethylenediamine, diethylenetriamine and tetraethylenepentamine) was determined potentiometrically. Species Fe(CN)₆(A)H _j ^(j–4) (A=amine) are formed in all the systems investigated, with j=1...n+2 (n=number of aminogroups). Some other complexes Fe(CN)₆(A)_iH_j (with i>1) were also found. The stability of these complexes is fairly high: the full protonated amine species, show for the reaction Fe(CN)₆ ^4- + H_nAⁿ⁺ = Fe(CN)₆(A)H_n ^(n-4) an equilibrium constant given by logK=0.686+2.10n. Factors affecting the stability are discussed in comparison with similar systems, together with the importance of interferences.     

以交联聚乙烯醇为载体的离子交换剂对蛋白质的分离性能

本文对阴离子交换剂ＤＥＡ—ＰＶＴ常压液相离子交换色谱分离蛋白质的性能、分离条件进行了探讨。结果表明其对蛋白质的分离性能良好，容易洗脱。与载体交联聚乙烯醇相比，ＤＥＡ—ＰＶＴ对蛋白质的非特异性吸附明显降低。     

Reactions of isomeric 3,6- and 3,5-di-tert-butyl-ortho-benzoquinones with NH3

The interaction of 3,6-di-tert-butyl-ortho-benzoquinone (1) and 3,5-di-tert-butyl-ortho-benzoquinone (2) with NH₃ in water—alcohol medium and with (NH₄)₂CO₃ in a solid phase has been studied. Redox processes with participation of a nucleophile of the medium take place for1, while2 reacts with NH₃ at the carbonyl group with transformation of the quinone imide. The mechanism of redox transformation of1 has been proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1789–1793, September, 1995.This work was carried out with financial support from the Russian Foundation for Basic Research (Project No. 94-03-08653).     

Structure of the 18-Crown-6 Complex with Ammonium Hexafluorosilicate and Water

The crystalline host–guest type complex [(18-crown-6NH₄)₂][SiF₆]4H₂Ohas been obtained as the result of the interaction of SiF₄2NH₃ with 18-crown-6 (18C6) in an aqueous medium. Crystal data: monoclinic, space groupC 2 c, a=26.541(2), b=8.363(2), c=20.469(2) Å, = 122.43(1)°and Z=4. The final R-value is 0.070 for 3253 reflections with I 2(I).The crystals consist of the complex [NH₄18C6]⁺ cations, [SiF₆]^2-anions and water molecules. The ammonium cation is hydrogen bonded by three of its H-atoms to the crown ether oxygen atoms with N(1) O separations2.923(5)–2.940(5) Å and by the fourth H-atom to the fluorine atom of thehexafluorosilicate anion, the N(1)F(4) distance being 2.797(6) Å.The conformation of the macrocycle and the hydrogen-bond geometry in thecomplex cation closely resemble those in related adducts between 18-crown-6and ammonium salts. All crystal components are connected via a system of hydrogen bonds into a ribbon along the b axis in the unit cell.     

弱碱性阴离子交换树脂分离1,6—二磷酸果糖的研究

采用弱碱性阴离子交换树脂HJ-30对发酵液中1，6-二磷酸果糖的分离进行了研究。详细地研究了树脂的吸附和脱附性能。实验结果表明，HJ-30树脂对FDP的吸附量达0．28gFDP／g湿树脂，以0．05mol／LNaCl洗脱光机磷和1mol／LNaCl洗脱1，6-二磷酸果糖，产品的收率和纯度分别为92％和99．4％。     

氟烷基三甲基硅化合物的合成和反应研究

羰基化合物的氟烷基化反应是把含氟基团引入有机分子中去的一个重要手段。文献报道的主要是通过氟烷基金属试剂来进行此反应。但氟烷基金属试剂不太稳定,容易分解。这就给它们的应用带来了许多不便。我们发现,氟烷基三甲基硅化合物(1)作为氟烷基阴离子前体,在比较温和的条件下,便可使醛发生氟烷基化反应。首先,参照文献方法,通过氟烷基格氏试剂与三甲基氯硅烷反应,方便地制得了两个新的氟烷基三甲基硅化合物 R_F-SiMe_3(1)。     

Matrix separation of palladium and iridium by the cellulose anion exchanger Cellex T and the subsequent determination of palladium at theμg/g-level

The preconcentration and separation of palladium and iridium from base metals is studied with cellulose (Cellex T) and styrene-divinylbenzene (Varion AT 400) anion exchangers. In spite of lower capacity of Cellex T to chloride complexes of Pd and Ir, it allowed to get a higher preconcentration factor. Yields of 92–99% are achieved for Pd and 96–97% for Ir from the solutions containing great excess of base and heavy metals. Graphite furnace atomic absorption spectrometry is used for the final measurements. The procedure has been applied to the determination of palladium in natural samples.     

一例可分离的双核铁氢自由基阳离子

成功分离得到了一例双核铁氢自由基阳离子盐cis-[Fe₂Cp₂（μ-H）（μ-PPh₂）（CO）₂]^·+[Al（OC（CF₃）₃）₄]^-（cis-1^·+[Al（OC（CF₃）₃）₄]^-）晶体，并使用单晶X射线衍射、电子顺磁共振、红外光谱、紫外-可见光谱以及密度泛函理论对它进行了表征和理论计算。电子顺磁共振和密度泛函理论计算分析表明，自由基的自旋密度主要均等分布于2个铁原子上。