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Three new ruthenium(II)-arene halido complexes, [(η6-p-cymene) RuX(L)] (1–3), were synthesized in a reaction of [(η6-p-cymene)RuX2]2 with 5-chloro-1H-benzimidazole-2-carboxylic acid (HL) in ethanol (X = Cl (1), Br (2), I (3)). The complexes were characterized by elemental analysis, mass spectrometry, IR, 1H and 13C NMR spectroscopy. The cytotoxic activity of the ligand precursor and its ruthenium complexes was tested by MTT assay in human cancer cell lines: lung adenocarcinoma (A549), myelogenous leukemia (K562) as well as in one normal human fetal lung fibroblast cell line (MRC-5). The results show that ruthenium(II)-arene complexes possess enhanced cytotoxicity when compared to HL in the range of concentrations up to 300 µM. In terms of halido ligand substitution, cytotoxic activity toward A549 and K562 cell lines in 1–3 serie significantly increased (e.g., IC50 values for K562: 1: 205.76 µM; 2: 174.77 µM; 3: 83.97 µM). All studied compounds were found to be ineffective toward MRC-5. Hydrolysis of 1–3 was followed by UV-vis spectroscopy at 25?°C, revealing ligand-substitution reactions at the Ru(II) center. Compounds 2 and 3 underwent rapid hydrolysis ranging from a few minutes for the aquation to ca. 20?min, confirming typical Ru-arene behavior in aqueous solutions.  相似文献   
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This paper reports a morphological phase-only correlation technique based on bit-map representation for recognition of color as well as grey images in a hybrid digital-optical correlation architecture. The color image is decomposed into its R, G and B components, and each component is further decomposed into eight disjoint elementary images depending upon the bit-map representation of the color value at each pixel. Bit-map representation of the pixel values of an image reduces the required computational time. A set of twenty-four disjoint wavelet-modified binary phase-only filters (WBPOFs) are generated from these bit-map decomposed images. The target image is similarly decomposed into eight disjoint images each of R, G and B and their digital Fourier transforms multiplied with the corresponding WBPOFs. The product functions thus obtained are added up to form a single resultant product function, whose optical Fourier transformation gives the correlation peaks for the presence of R, G and B components in the image. The single product function overcomes the necessity of obtaining the final optical Fourier transformation of the R, G and B components separately. The novelty of this approach lies in the fact that the WBPOFs synthesized by this procedure are thus able to identify both colored as well as gray images and can tolerate salt-and-pepper noise to a considerable extent.  相似文献   
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In this paper we present a simple and unified approach to the fixed point results on cone symmetric spaces and metric type spaces based on symmetric spaces fixed point theory. We also give a new characterization of semi-metric spaces with open balls.  相似文献   
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A range of porous carbon‐based monolithic (PCM) rods with flow‐through pore sizes of 1, 2, 5 and 10 μm, were produced using a silica particle template method. The rods were characterised using SEM and energy‐dispersive X‐ray spectroscopy, BET surface area and porous structure analysis, dilatometry and thermal gravimetry. SEM evaluation of the carbon monolithic structures revealed an interconnected rigid bimodal porous structure and energy‐dispersive X‐ray spectroscopy analysis verified the quantitative removal of the embedded silica beads. The specific surface areas of the 1, 2, 5 and 10 μm rods were 178, 154, 84 and 125 m2/g after pyrolysis and silica removal, respectively. Shrinkage of the monolithic rods during pyrolysis is proportional to the particle size of the silica used and ranged from 9 to 12%. Mercury porosimetry showed a narrow distribution of pore sizes, with an average of ~700 nm for the 1 μm carbon monolith. The suitability of bare and surface oxidised PCM rods for the use as a stationary phase for reversed and normal phase LC was explored. The additional modification of PCM rods with gold micro‐particles followed by 6‐mercaptohexanoic acid was performed and ion‐exchange properties were evaluated.  相似文献   
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The detection limits of the ANTS (8-aminonaphthalene-1,3,6-trisulfonic acid) label and ANTS maltose as a model carbohydrate conjugate were investigated with on-column UV and laser induced fluorescence detection. Under capillary electrophoresis conditions, the concentration and mass detection limits were found to be 5×10–7 mol/l or 8 femtomole with UV and 5×10–8 mol/l or 400 attomole with laser induced fluorescence detection, respectively. Including the derivatization reaction, the best concentration detection limit increases to 1×10–6 mol/l carbohydrate. A model calculation shows that these detection levels are still insufficient to match those of current protein sequencing protocols.Derivatization conditions for dextran and polygalacturonic acid ladders are described with subsequent fast separation in a capillary electrophoresis system under acidic pH buffer conditions. Up to 30 oligomers could be separated in less than 10 min. The application of ANTS labelled carbohydrate analysis in the food industry is demonstrated with the carbohydrate fraction of sweets and the kinetic monitoring of the hydrolysis of polygalacturonic acid.The described ANTS derivitization protocol works with as little as 5 g carbohydrate as demonstrated with a complex oligosaccharide labelled in a reaction volume as little as 2 l. To demonstrate the applicability of this approach to complex carbohydrate analysis, an oligosaccharide mixture derived from human Immunoglobuline G was labelled and separated within 5 min. Separation efficiency and speed are superior to state-of-the-art chromatographic methods. Both electrophoretic and chromatographic methods are complementary because of their different separation mechanism. The implications of using capillary electrophoresis with laser induced fluorescence and appropriate labelling strategies for structural and compositional analysis of complex carbohydrates are discussed.Dedicated to Professor Dr. Dieter Klockow on the occasion of his 60th birthday  相似文献   
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The purification of adenosine deaminase from human erythrocytes is reported. By means of classical procedures and by using affinity chromatography as the last step, the enzyme is purified 760,000-fold with a yield of 32%. The affinity resin is composed of purine riboside (nebularine) linked to Sepharose CL6B. Since the compound has no leaving group at the C-6 position the affinity gel is stable and the chromatography can be repeated several times (up to fifteen times in eight months). Purine riboside was chosen because its potency as a reversible inhibitor of adenosine deaminase is greater than that of inosine (a low-affinity inhibitor), but lower than that of erythro-9-(2-hydroxy-3-nonyl)adenine (a high-affinity inhibitor).  相似文献   
10.
Journal of Radioanalytical and Nuclear Chemistry - This study is a preliminary experiment to examine the effect of amines as additive in eluents for separating neighboring lanthanides (Lu and Yb)...  相似文献   
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