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ATR-FTIR and XPS study on the structure of complexes formed upon the adsorption of simple organic acids on aluminum hydroxide
GUAN Xiao-hong,CHEN Guang-hao,SHANG Chii,
GUAN Xiao-hong
,CHEN Guang-hao,SHANG Chii

环境科学学报(英文版) , 2007,
Abstract: Information on the binding of organic ligands to metal (hydr)oxide surfaces is useful for understanding the adsorption behaviour of natural organic matter (NOM) on metal (hydr)oxide. In this study, benzoate and salicylate were employed as the model organic ligands and aluminum hydroxide as the metal hydroxide. The attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra revealed that the ligands benzoate and salicylate do coordinate directly with the surface of hydrous aluminum hydroxide, thereby forming inner-sphere surface complexes. It is concluded that when the initial pH is acidic or neutral, monodentate and bridging complexes are to be formed between benzoate and aluminum hydroxide while bridging complexes predominate when the initial pH is alkalic. Monodentate and bridging complexes can be formed at pH 5 while precipitate and bridging complexes are formed at pH 7 when salicylate anions are adsorbed on aluminum hydroxide. The X-ray photoelectron (XP) spectra demonstrated the variation of C 1s binding energy in the salicyate and phenolic groups before and after adsorption. It implied that the benzoate ligands are adsorbed through the complexation between carboxylate moieties and the aluminum hydroxide surface, while both carboxylate group and phenolic group are involved in the complexation reaction when salicylate is adsorbed onto aluminum hydroxide. The information offered by the XPS confirmed the findings obtained with ATR-FTIR.
Synthesis, Structure, and Antiproliferative Activity of Three Gallium(III) Azole Complexes  [PDF]
Stergios Zanias,Giannis S. Papaefstathiou,Catherine P. Raptopoulou,Konstantinos T. Papazisis,Vasiliki Vala,Dimitra Zambouli,Alexandros H. Kortsaris,Dimitrios A. Kyriakidis,Theodoros F. Zafiropoulos
Bioinorganic Chemistry and Applications , 2010, DOI: 10.1155/2010/168030
Abstract: As part of our interest into the bioinorganic chemistry of gallium, gallium(III) complexes of the azole ligands 2,1,3-benzothiadiazole (btd), 1,2,3-benzotriazole (btaH), and 1-methyl-4,5-diphenylimidazole (L) have been isolated. Reaction of btaH or btd with or resulted in the mononuclear complexes (1) and (2), respectively, while treatment of with L resulted in the anionic complex (3). All three complexes were characterized by single-crystal X-ray crystallography and IR spectroscopy, while their antiproliferative activities were investigated against a series of human and mouse cancer cell lines. 1. Introduction The coordination chemistry of gallium(III) has become an area of increasing research activity due to its relevance with both materials science [1–6] and biomedical developments [7–21]. In the area of materials science, for example, complex [Ga2(saph)2q2], where saph2? is the Schiff-base ligand bis(salicylidene-o-aminophenolate)(-2) and q? is 8-quinolinate(-1), is a very good candidate as a novel electron-transporting and emitting material for organic light-emitting diodes (OLEDs) [4]. [Gaq3] is also a promising electroluminescence (EL) material, exhibiting higher power efficiency than the aluminum analogue, [Alq3] [5, 6]. The biological interest of gallium(III) complexes originates from the incorporation of gallium(III) radionuclides (67Ga3+, 68Ga3+) into diagnostic radiopharmaceuticals [7]. In addition, the gallium salts GaCl3 and Ga(NO3)3 as well as few gallium(III) complexes [8–19] have exhibited antitumour activity, while Ga(NO3)3 and some GaCl3/L complexes (L = various azoles) showed in vitro anti-HIV (HIV = human immunodeficiency virus) activity [20]. The biological activity of gallium(III) complexes has often been attributed to the fact that gallium(III) is the diamagnetic biological mimic of iron(III) [21]. It is worth mentioning that [Gaq3], which is of current interest in materials science [5, 6], is also being evaluated in clinical trials, along with other Ga(III) complexes, such as gallium maltolate [tris(3-hydroxy-2-methyl-4H-pyran-4-onato)gallium(III)], for anticancer activity [22–24]. Following our interest in the coordination chemistry of gallium(III) [25–31] which is focused on the synthesis, structural characterization, physical/spectroscopic study and evaluation of the biological (antitumour and antiviral) activity of Ga(III) complexes with biologically relevant and nonrelevant ligands, we report herein the synthesis, structural characterization, and antiproliferative activity of three gallium complexes based on the azole
Synthesis, characterization and photoluminescence of aluminum N-aryloxo functionalized β-ketoiminate complexes
Tao Feng,HongMei Peng,YingMing Yao,Yong Zhang,Qi Shen,YanXiang Cheng
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4458-3
Abstract: The synthesis, characterization and luminescent properties of aluminum complexes containing a dianionic N-aryloxo functionalized β-ketoiminate ligand are presented. 4-(2-Hydroxy-5-R-phenyl)imino-2-pentanone (R = Me, L1H2; R = tert-butyl, L2H2) ligands reacted with AlEt3 in tetrahydrofuran to give the aluminum complexes (L1AlEt)2 (1) and (L2AlEt)2 (2) in reasonable isolated yields. X-ray diffraction revealed that complexes 1 and 2 have solvent-free centrosymmetric dimeric structures, and each aluminum center has distorted trigonal bipyramidal geometry. At room temperature, complexes 1 and 2 exhibit blue photoluminescence in acetonitrile with maximum emission wavelengths of 419 and 413 nm, respectively.
Analysis of organic compounds in coal gasification wastewater
Wang Jusi,Zhao LihuiResearch Center for Eeo-Environmental Sciences,Chinese Academy of Sciences,Beijing,China,
Wang Jusi
,Zhao Lihui

环境科学学报(英文版) , 1992,
Abstract: A procedure for analysis of organic pollutants in coal gasification wastewater was developed, including a series extraction steps at different pH, followed by LC separation or resin adsorption, then analyzed by GC or GC/MS. More than 200 organic pollutants in 22 categories were determined. CH2CL2 extraction at NaHCO3 presence was used to separate carboxylic acids with phenolic compounds in aqueous. Derivatization with acetic anhydride was used for analyses of mono-, di-, poly-hydroxyl phenolic compounds. 21 mono-hydroxyl phenols and 13 di-hydroxyl phenols were determined from the coai gasification wastewater samples. Derivatization with BF3-CH3OH was used for analysis of carboxylic acid. 17 mono-carboxyl, 4 di-carboxyl acids and 6 aromatic acids were determined from coal gasification wastewater samples.
Organic wastes and the industrial technologies of their coprocessing with coal  [PDF]
Vlastimil K?í?,Jaroslav Buchtele
Acta Montanistica Slovaca , 2005,
Abstract: The production of solid waste in the Czech Republic was a round 40 Mt in 2000 – 2002 yearly. The organic compounds in the municipal waste (plastics, polymers, paper, wood, textile) and in the agricultural and forest waste (biomass) are mainly burned and partially landfilled. New industrial waste processes and their heat conversion in mixtures with coal allow an economical and energetically a more efficient utilization. They also open the way to the production of liquid fuels and chemicals.
Comparative study of the growth of sputtered aluminum oxide films on organic and inorganic substrates  [PDF]
Stefan Sellner,Alexander Gerlach,Stefan Kowarik,Frank Schreiber,Helmut Dosch,Stephan Meyer,Jens Pflaum,Gerhard Ulbricht
Physics , 2007, DOI: 10.1016/j.tsf.2007.12.151
Abstract: We present a comparative study of the growth of the technologically highly relevant gate dielectric and encapsulation material aluminum oxide in inorganic and also organic heterostructures. Atomic force microscopy studies indicate strong similarities in the surface morphology of aluminum oxide films grown on these chemically different substrates. In addition, from X-ray reflectivity measurements we extract the roughness exponent \beta of aluminum oxide growth on both substrates. By renormalising the aluminum oxide roughness by the roughness of the underlying organic film we find good agreement with \beta as obtained from the aluminum oxide on silicon oxide (\beta = 0.38 \pm 0.02), suggesting a remarkable similarity of the aluminum oxide growth on the two substrates under the conditions employed.
Extraction of organic compounds from brown coal
Anton Zubrik,Mária Skybová,Silvia ?uvanová,?udmila Tur?ániová
Acta Montanistica Slovaca , 2005,
Abstract: The paper presents the study on the extraction of organic compounds (low-molecular weight - diterpenes, high-molecular weight - fullerenes and humic acids) from Handlová brown coal and pyrolytic soot. It was confirmed that the coal extract with a diterpene content - 16 β (H) kaurene was obtained by the supercritical fluid extraction (using CO2 and modificator - tetrahydrofurane/acetone, 8:2 w/w) at T = 90 oC and p = 30 MPa. The occurrence of fullerenes in the toluene extract of solid carbon product has confirmed by the MALDI - TOF - MS and UV-VIS spectroscopy. In the extraction process of GACL (Grinding Aqueous Caustic Leaching) at the concentration of 0.1 % NaOH, the content of humic acids (HK) in the physically untreated and pretreated sample increased by 6.09 and 4.57 times, respectively. In the case of higher leaching agent concentration (2 % NaOH), the content of HK in the physically untreated and pretreated sample increased by 8,67 and 8,21 times, respectively.
An Industrial System Powered by Wind and Coal for Aluminum Production: A Case Study of Technical Demonstration and Economic Feasibility  [PDF]
Yuan-Zhang Sun,Jin Lin,Yong-Hua Song,Jian Xu,Xiao-Ming Li,Jian-Xun Dong
Energies , 2012, DOI: 10.3390/en5114844
Abstract: This paper presents a case study of an isolated industrial power system for aluminum production. The novel concept is that the cost of aluminum electrolysis can be significantly reduced by innovative application of hybrid systems incorporating wind energy and low-grade coal. In addition, the low-grade coal, which sale is not profitable in the market, can be locally consumed by the isolated power system. The power system thus fully utilizes the local resources in an effective and economic manner. However, several technical and economic issues are still of concern because the industrial system is isolated from the state grid. This paper hence discusses these issues and demonstrates the feasibility of such a hybrid power system from the technical and economic perspectives.
MAGNETIC BEHAVIOR AND ANTIBACTERIAL ACTIVITY OF IRON (III) COMPLEXES
CORTéS-CORTéS,PIEDAD; ATRIA,ANA MARíA; CONTRERAS,MARTíN; PE?A,OCTAVIO; FERNáNDEZ,KATIA; CORSINI,GINO;
Journal of the Chilean Chemical Society , 2008, DOI: 10.4067/S0717-97072008000200019
Abstract: the preparation, magnetic characterization and antimicrobial properties of the complexes [fe30(ch3coo)6(ch3cooh)(h20)]cl(meimid)-(h20) (1) and [fe402(ch3coo)702(bpa)2(h20)]- ch.25(ch3ch2oh)(h20) (2), where melmid is 2-methyl-imidazolium and bpa is 2,2'-bipyridine, are described. the variable temperature susceptibilities of these complexes were investigated in the temperature range 2-300k. the data have been modeled on the assumption of "butterfly" arranged for (2) and equilateral triangle of ferric ions for (1). the antimicrobial activities of these complexes have been screened in vitro against different bacterial strains. the complexes (1) and (2) display activity over gram negative bacteria and these compounds not present activity over gram positive strains. these complexes have bacteriostatic effect over bacterial target. the toxicity analyses of iron complexes showed these have cytotoxicity effect to values around the mic on human cell.
MAGNETIC BEHAVIOR AND ANTIBACTERIAL ACTIVITY OF IRON (III) COMPLEXES  [cached]
PIEDAD CORTéS-CORTéS,ANA MARíA ATRIA,MARTíN CONTRERAS,OCTAVIO PE?A
Journal of the Chilean Chemical Society , 2008,
Abstract: The preparation, magnetic characterization and antimicrobial properties of the complexes [Fe(3)0(CH3COO)6(CH3COOH)(H(2)0)]Cl(MeImid)-(H(2)0) (1) and [Fe(4)0(2)(CH3COO)(7)0(2)(BPA)2(H(2)0)]- CH.25(CH3CH2OH)(H(2)0) (2), where Melmid is 2-methyl-imidazolium and BPA is 2,2'-bipyridine, are described. The variable temperature susceptibilities of these complexes were investigated in the temperature range 2-300K. The data have been modeled on the assumption of "butterfly" arranged for (2) and equilateral triangle of ferric ions for (1). The antimicrobial activities of these complexes have been screened in vitro against different bacterial strains. The complexes (1) and (2) display activity over Gram negative bacteria and these compounds not present activity over Gram positive strains. These complexes have bacteriostatic effect over bacterial target. The toxicity analyses of iron complexes showed these have cytotoxicity effect to values around the MIC on human cell.
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