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101.
Minna GünesÛ Kalle Nttinen Jussi Valkonen 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):i21-i22
The title compound, CaCs2[Ag2(SCN)6]·2H2O, forms a continuous structure where the Ag atoms form chains with S atoms in the c‐axis direction. The chains are bonded together through Cs and Ca atoms. The crystal water of the structure is bonded to the Ca atoms, which lie on centers of symmetry. 相似文献
102.
We herein report three new coordination polymers generated from Cu(II) carboxylates (mal, 2ac, fum) and conformationally flexible bifunctional IX as building blocks. All the three complexes adopt unique structures in the solid state. The complex [Cu2(mal)2(IX)2(H2O)6]n crystallizes as orthorhombic co-linear rods with space group P2(1) P2(1) P2(1). Each rod is further formed of two tightly intertwined strings. The second polymer [Cu2(ac)4(IX)2]n crystallizes with space group P1 which consists of two sets of intersecting 2D sheets composed of parallel rods which interpenetrate to form a fully interlocked 3D structure. In both these complexes IX coordinates in the anti mode. The third polymer [Cu2(fum)2(IX)2(H2O)2]n possesses a monoclinic crystal system with space group C2/c and crystallizes as 1D straps. Cu–fum–Cu forms the base of the string which is alternatively garlanded by a macrocycle derived from Cu2(IX)2 unit, where IX coordinates in the syn fashion. The present study suggests that the use of a rigid building block with a flexible organic ligand leads to a better prediction of the final structure of the polymeric array. 相似文献
103.
104.
H. Schmalfuss H. Werner K. Kalle C. Schulze B. Tollens E. Sauer und Glaser 《Fresenius' Journal of Analytical Chemistry》1926,68(11):411-414
Ohne Zusammenfassung 相似文献
105.
On highly palindromic words 总被引:1,自引:0,他引:1
We study some properties of palindromic (scattered) subwords of binary words. In view of the classical problem on subwords, we show that the set of palindromic subwords of a word characterizes the word up to reversal.Since each word trivially contains a palindromic subword of length at least half of its length-a power of the prevalent letter-we call a word that does not contain any palindromic subword longer than half of its length minimal palindromic. We show that every minimal palindromic word is abelian unbordered, that is, no proper suffix of the word can be obtained by permuting the letters of a proper prefix.We also propose to measure the degree of palindromicity of a word w by the ratio |rws|/|w|, where the word rws is minimal palindromic and rs is as short as possible. We prove that the ratio is always bounded by four, and construct a sequence of words that achieves this bound asymptotically. 相似文献
106.
107.
Truus K Vaher M Koel M Mähar A Taure I 《Analytical and bioanalytical chemistry》2004,379(5-6):849-852
Two different types of bioactive components of the seaweed Fucus vesiculosus were analysed: (1) polyphenols (phlorotannins) by capillary electrophoresis (CE) and (2) mineral part (including bioactive microelements) by neutron activation analysis (NAA). CE experiments were carried out using a UV detector (at 210 nm) and an uncoated silica capillary. The best separation was achieved at a voltage of 20 kV using borate or acetate buffer in a methanol/acetonitrile mixture as background electrolyte. The CE analysis data were confirmed by high-performance liquid chromatography (HPLC). Determination of mineral composition of algal biomass by NAA was performed on the basis of various nuclides; the best results (from 38 elements determined) were obtained for Mn, Fe, Zn, As, Br, Sr, I, Ba, Au and Hg. 相似文献
108.
Trempe JF Denisov A Gehring K 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,164(2):329-337
Measurement of dipolar couplings, chemical shift anisotropies, and quadrupole couplings in oriented media such as liquid crystals are of great importance for extraction of structural parameters in biological macromolecules. Here, we introduce a new technique, SAD-REDOR, that consists of recoupling heteronuclear dipolar couplings in molecules dissolved in a single-domain liquid crystal or other oriented medium through the combined use of magic-angle spinning and rotor-synchronized radiofrequency pulses. This application of the REDOR pulse sequence to oriented media offers several advantages such as selectivity over the type of coupling recovered and tunable scaling of the interaction. The effectiveness of the technique is demonstrated both theoretically and experimentally, using the recently developed polyacrylamide-stabilized Pf1 phage medium and 15N-labeled benzamide as the aligned molecule. 相似文献
109.
110.
L Oresmaa H Tarvainen K Machal M Haukka 《Dalton transactions (Cambridge, England : 2003)》2012,41(36):11170-11175
Carbon monoxide has been found to possess various beneficial effects in living organisms. To study the effects of CO further and to develop potential pharmaceutical agents, a meaningful method for delivering CO to the target organ is needed. It has been found that under physiological conditions various metal carbonyl complexes release carbon monoxide. In this study six novel ruthenium carbonyl complexes Ru(IMOX)(CO)(2)(COOR)Cl(1) (IMOX: imidazolecarbaldehyde oxime, R: Me, Et) were prepared and tested as carbon monoxide releasing molecules (CORMs). Synthesis of the complexes was performed under mild conditions in alcoholic solutions. The ability to release CO was tested spectrophotometrically by following the transformation of deoxymyoglobin to carbonmonoxy myoglobin. All of the complexes studied were found to release CO. Compared to formerly studied ruthenium-based CORMs these complexes offer a way for slower CO release. 相似文献